diff options
Diffstat (limited to 'kernel')
124 files changed, 5762 insertions, 2736 deletions
diff --git a/kernel/.gitignore b/kernel/.gitignore index 790d83c7d160..b3097bde4e9c 100644 --- a/kernel/.gitignore +++ b/kernel/.gitignore @@ -5,4 +5,3 @@ config_data.h config_data.gz timeconst.h hz.bc -x509_certificate_list diff --git a/kernel/audit.c b/kernel/audit.c index 662c007635fb..5ffcbd354a52 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -407,16 +407,33 @@ static void audit_printk_skb(struct sk_buff *skb) static void kauditd_send_skb(struct sk_buff *skb) { int err; + int attempts = 0; +#define AUDITD_RETRIES 5 + +restart: /* take a reference in case we can't send it and we want to hold it */ skb_get(skb); err = netlink_unicast(audit_sock, skb, audit_nlk_portid, 0); if (err < 0) { - BUG_ON(err != -ECONNREFUSED); /* Shouldn't happen */ + pr_err("netlink_unicast sending to audit_pid=%d returned error: %d\n", + audit_pid, err); if (audit_pid) { - pr_err("*NO* daemon at audit_pid=%d\n", audit_pid); - audit_log_lost("auditd disappeared"); - audit_pid = 0; - audit_sock = NULL; + if (err == -ECONNREFUSED || err == -EPERM + || ++attempts >= AUDITD_RETRIES) { + char s[32]; + + snprintf(s, sizeof(s), "audit_pid=%d reset", audit_pid); + audit_log_lost(s); + audit_pid = 0; + audit_sock = NULL; + } else { + pr_warn("re-scheduling(#%d) write to audit_pid=%d\n", + attempts, audit_pid); + set_current_state(TASK_INTERRUPTIBLE); + schedule(); + __set_current_state(TASK_RUNNING); + goto restart; + } } /* we might get lucky and get this in the next auditd */ audit_hold_skb(skb); @@ -684,25 +701,22 @@ static int audit_netlink_ok(struct sk_buff *skb, u16 msg_type) return err; } -static int audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type) +static void audit_log_common_recv_msg(struct audit_buffer **ab, u16 msg_type) { - int rc = 0; uid_t uid = from_kuid(&init_user_ns, current_uid()); pid_t pid = task_tgid_nr(current); if (!audit_enabled && msg_type != AUDIT_USER_AVC) { *ab = NULL; - return rc; + return; } *ab = audit_log_start(NULL, GFP_KERNEL, msg_type); if (unlikely(!*ab)) - return rc; + return; audit_log_format(*ab, "pid=%d uid=%u", pid, uid); audit_log_session_info(*ab); audit_log_task_context(*ab); - - return rc; } int is_audit_feature_set(int i) @@ -1357,16 +1371,16 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask, if (unlikely(audit_filter_type(type))) return NULL; - if (gfp_mask & __GFP_WAIT) { + if (gfp_mask & __GFP_DIRECT_RECLAIM) { if (audit_pid && audit_pid == current->pid) - gfp_mask &= ~__GFP_WAIT; + gfp_mask &= ~__GFP_DIRECT_RECLAIM; else reserve = 0; } while (audit_backlog_limit && skb_queue_len(&audit_skb_queue) > audit_backlog_limit + reserve) { - if (gfp_mask & __GFP_WAIT && audit_backlog_wait_time) { + if (gfp_mask & __GFP_DIRECT_RECLAIM && audit_backlog_wait_time) { long sleep_time; sleep_time = timeout_start + audit_backlog_wait_time - jiffies; @@ -1566,14 +1580,14 @@ void audit_log_n_string(struct audit_buffer *ab, const char *string, * @string: string to be checked * @len: max length of the string to check */ -int audit_string_contains_control(const char *string, size_t len) +bool audit_string_contains_control(const char *string, size_t len) { const unsigned char *p; for (p = string; p < (const unsigned char *)string + len; p++) { if (*p == '"' || *p < 0x21 || *p > 0x7e) - return 1; + return true; } - return 0; + return false; } /** diff --git a/kernel/audit.h b/kernel/audit.h index dadf86a0e59e..de6cbb7cf547 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -301,7 +301,7 @@ extern int audit_exe_compare(struct task_struct *tsk, struct audit_fsnotify_mark #ifdef CONFIG_AUDIT_TREE extern struct audit_chunk *audit_tree_lookup(const struct inode *); extern void audit_put_chunk(struct audit_chunk *); -extern int audit_tree_match(struct audit_chunk *, struct audit_tree *); +extern bool audit_tree_match(struct audit_chunk *, struct audit_tree *); extern int audit_make_tree(struct audit_krule *, char *, u32); extern int audit_add_tree_rule(struct audit_krule *); extern int audit_remove_tree_rule(struct audit_krule *); diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index 94ecdabda8e6..5efe9b299a12 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -197,13 +197,13 @@ struct audit_chunk *audit_tree_lookup(const struct inode *inode) return NULL; } -int audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree) +bool audit_tree_match(struct audit_chunk *chunk, struct audit_tree *tree) { int n; for (n = 0; n < chunk->count; n++) if (chunk->owners[n].owner == tree) - return 1; - return 0; + return true; + return false; } /* tagging and untagging inodes with trees */ diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index 7714d93edb85..b8ff9e193753 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -39,13 +39,13 @@ * Locking model: * * audit_filter_mutex: - * Synchronizes writes and blocking reads of audit's filterlist - * data. Rcu is used to traverse the filterlist and access - * contents of structs audit_entry, audit_watch and opaque - * LSM rules during filtering. If modified, these structures - * must be copied and replace their counterparts in the filterlist. - * An audit_parent struct is not accessed during filtering, so may - * be written directly provided audit_filter_mutex is held. + * Synchronizes writes and blocking reads of audit's filterlist + * data. Rcu is used to traverse the filterlist and access + * contents of structs audit_entry, audit_watch and opaque + * LSM rules during filtering. If modified, these structures + * must be copied and replace their counterparts in the filterlist. + * An audit_parent struct is not accessed during filtering, so may + * be written directly provided audit_filter_mutex is held. */ /* Audit filter lists, defined in <linux/audit.h> */ diff --git a/kernel/bpf/Makefile b/kernel/bpf/Makefile index e6983be12bd3..13272582eee0 100644 --- a/kernel/bpf/Makefile +++ b/kernel/bpf/Makefile @@ -1,2 +1,4 @@ obj-y := core.o -obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o hashtab.o arraymap.o helpers.o + +obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o inode.o helpers.o +obj-$(CONFIG_BPF_SYSCALL) += hashtab.o arraymap.o diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 29ace107f236..3f4c99e06c6b 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -15,6 +15,7 @@ #include <linux/slab.h> #include <linux/mm.h> #include <linux/filter.h> +#include <linux/perf_event.h> /* Called from syscall */ static struct bpf_map *array_map_alloc(union bpf_attr *attr) @@ -48,7 +49,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr) array->map.key_size = attr->key_size; array->map.value_size = attr->value_size; array->map.max_entries = attr->max_entries; - + array->map.pages = round_up(array_size, PAGE_SIZE) >> PAGE_SHIFT; array->elem_size = elem_size; return &array->map; @@ -291,14 +292,23 @@ static void *perf_event_fd_array_get_ptr(struct bpf_map *map, int fd) attr = perf_event_attrs(event); if (IS_ERR(attr)) - return (void *)attr; + goto err; - if (attr->type != PERF_TYPE_RAW && - attr->type != PERF_TYPE_HARDWARE) { - perf_event_release_kernel(event); - return ERR_PTR(-EINVAL); - } - return event; + if (attr->inherit) + goto err; + + if (attr->type == PERF_TYPE_RAW) + return event; + + if (attr->type == PERF_TYPE_HARDWARE) + return event; + + if (attr->type == PERF_TYPE_SOFTWARE && + attr->config == PERF_COUNT_SW_BPF_OUTPUT) + return event; +err: + perf_event_release_kernel(event); + return ERR_PTR(-EINVAL); } static void perf_event_fd_array_put_ptr(void *ptr) diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 67c380cfa9ca..334b1bdd572c 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -82,6 +82,8 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags) if (fp == NULL) return NULL; + kmemcheck_annotate_bitfield(fp, meta); + aux = kzalloc(sizeof(*aux), GFP_KERNEL | gfp_extra_flags); if (aux == NULL) { vfree(fp); @@ -90,6 +92,7 @@ struct bpf_prog *bpf_prog_alloc(unsigned int size, gfp_t gfp_extra_flags) fp->pages = size / PAGE_SIZE; fp->aux = aux; + fp->aux->prog = fp; return fp; } @@ -110,8 +113,11 @@ struct bpf_prog *bpf_prog_realloc(struct bpf_prog *fp_old, unsigned int size, fp = __vmalloc(size, gfp_flags, PAGE_KERNEL); if (fp != NULL) { + kmemcheck_annotate_bitfield(fp, meta); + memcpy(fp, fp_old, fp_old->pages * PAGE_SIZE); fp->pages = size / PAGE_SIZE; + fp->aux->prog = fp; /* We keep fp->aux from fp_old around in the new * reallocated structure. @@ -722,11 +728,36 @@ void bpf_prog_free(struct bpf_prog *fp) struct bpf_prog_aux *aux = fp->aux; INIT_WORK(&aux->work, bpf_prog_free_deferred); - aux->prog = fp; schedule_work(&aux->work); } EXPORT_SYMBOL_GPL(bpf_prog_free); +/* RNG for unpriviledged user space with separated state from prandom_u32(). */ +static DEFINE_PER_CPU(struct rnd_state, bpf_user_rnd_state); + +void bpf_user_rnd_init_once(void) +{ + prandom_init_once(&bpf_user_rnd_state); +} + +u64 bpf_user_rnd_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) +{ + /* Should someone ever have the rather unwise idea to use some + * of the registers passed into this function, then note that + * this function is called from native eBPF and classic-to-eBPF + * transformations. Register assignments from both sides are + * different, f.e. classic always sets fn(ctx, A, X) here. + */ + struct rnd_state *state; + u32 res; + + state = &get_cpu_var(bpf_user_rnd_state); + res = prandom_u32_state(state); + put_cpu_var(state); + + return res; +} + /* Weak definitions of helper functions in case we don't have bpf syscall. */ const struct bpf_func_proto bpf_map_lookup_elem_proto __weak; const struct bpf_func_proto bpf_map_update_elem_proto __weak; diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c index 83c209d9b17a..19909b22b4f8 100644 --- a/kernel/bpf/hashtab.c +++ b/kernel/bpf/hashtab.c @@ -17,7 +17,7 @@ struct bpf_htab { struct bpf_map map; struct hlist_head *buckets; - spinlock_t lock; + raw_spinlock_t lock; u32 count; /* number of elements in this hashtable */ u32 n_buckets; /* number of hash buckets */ u32 elem_size; /* size of each element in bytes */ @@ -82,12 +82,16 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr) for (i = 0; i < htab->n_buckets; i++) INIT_HLIST_HEAD(&htab->buckets[i]); - spin_lock_init(&htab->lock); + raw_spin_lock_init(&htab->lock); htab->count = 0; htab->elem_size = sizeof(struct htab_elem) + round_up(htab->map.key_size, 8) + htab->map.value_size; + + htab->map.pages = round_up(htab->n_buckets * sizeof(struct hlist_head) + + htab->elem_size * htab->map.max_entries, + PAGE_SIZE) >> PAGE_SHIFT; return &htab->map; free_htab: @@ -230,7 +234,7 @@ static int htab_map_update_elem(struct bpf_map *map, void *key, void *value, l_new->hash = htab_map_hash(l_new->key, key_size); /* bpf_map_update_elem() can be called in_irq() */ - spin_lock_irqsave(&htab->lock, flags); + raw_spin_lock_irqsave(&htab->lock, flags); head = select_bucket(htab, l_new->hash); @@ -266,11 +270,11 @@ static int htab_map_update_elem(struct bpf_map *map, void *key, void *value, } else { htab->count++; } - spin_unlock_irqrestore(&htab->lock, flags); + raw_spin_unlock_irqrestore(&htab->lock, flags); return 0; err: - spin_unlock_irqrestore(&htab->lock, flags); + raw_spin_unlock_irqrestore(&htab->lock, flags); kfree(l_new); return ret; } @@ -291,7 +295,7 @@ static int htab_map_delete_elem(struct bpf_map *map, void *key) hash = htab_map_hash(key, key_size); - spin_lock_irqsave(&htab->lock, flags); + raw_spin_lock_irqsave(&htab->lock, flags); head = select_bucket(htab, hash); @@ -304,7 +308,7 @@ static int htab_map_delete_elem(struct bpf_map *map, void *key) ret = 0; } - spin_unlock_irqrestore(&htab->lock, flags); + raw_spin_unlock_irqrestore(&htab->lock, flags); return ret; } diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 1447ec09421e..4504ca66118d 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -93,13 +93,8 @@ const struct bpf_func_proto bpf_map_delete_elem_proto = { .arg2_type = ARG_PTR_TO_MAP_KEY, }; -static u64 bpf_get_prandom_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5) -{ - return prandom_u32(); -} - const struct bpf_func_proto bpf_get_prandom_u32_proto = { - .func = bpf_get_prandom_u32, + .func = bpf_user_rnd_u32, .gpl_only = false, .ret_type = RET_INTEGER, }; diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c new file mode 100644 index 000000000000..be6d726e31c9 --- /dev/null +++ b/kernel/bpf/inode.c @@ -0,0 +1,387 @@ +/* + * Minimal file system backend for holding eBPF maps and programs, + * used by bpf(2) object pinning. + * + * Authors: + * + * Daniel Borkmann <daniel@iogearbox.net> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + */ + +#include <linux/module.h> +#include <linux/magic.h> +#include <linux/major.h> +#include <linux/mount.h> +#include <linux/namei.h> +#include <linux/fs.h> +#include <linux/kdev_t.h> +#include <linux/filter.h> +#include <linux/bpf.h> + +enum bpf_type { + BPF_TYPE_UNSPEC = 0, + BPF_TYPE_PROG, + BPF_TYPE_MAP, +}; + +static void *bpf_any_get(void *raw, enum bpf_type type) +{ + switch (type) { + case BPF_TYPE_PROG: + atomic_inc(&((struct bpf_prog *)raw)->aux->refcnt); + break; + case BPF_TYPE_MAP: + atomic_inc(&((struct bpf_map *)raw)->refcnt); + break; + default: + WARN_ON_ONCE(1); + break; + } + + return raw; +} + +static void bpf_any_put(void *raw, enum bpf_type type) +{ + switch (type) { + case BPF_TYPE_PROG: + bpf_prog_put(raw); + break; + case BPF_TYPE_MAP: + bpf_map_put(raw); + break; + default: + WARN_ON_ONCE(1); + break; + } +} + +static void *bpf_fd_probe_obj(u32 ufd, enum bpf_type *type) +{ + void *raw; + + *type = BPF_TYPE_MAP; + raw = bpf_map_get(ufd); + if (IS_ERR(raw)) { + *type = BPF_TYPE_PROG; + raw = bpf_prog_get(ufd); + } + + return raw; +} + +static const struct inode_operations bpf_dir_iops; + +static const struct inode_operations bpf_prog_iops = { }; +static const struct inode_operations bpf_map_iops = { }; + +static struct inode *bpf_get_inode(struct super_block *sb, + const struct inode *dir, + umode_t mode) +{ + struct inode *inode; + + switch (mode & S_IFMT) { + case S_IFDIR: + case S_IFREG: + break; + default: + return ERR_PTR(-EINVAL); + } + + inode = new_inode(sb); + if (!inode) + return ERR_PTR(-ENOSPC); + + inode->i_ino = get_next_ino(); + inode->i_atime = CURRENT_TIME; + inode->i_mtime = inode->i_atime; + inode->i_ctime = inode->i_atime; + + inode_init_owner(inode, dir, mode); + + return inode; +} + +static int bpf_inode_type(const struct inode *inode, enum bpf_type *type) +{ + *type = BPF_TYPE_UNSPEC; + if (inode->i_op == &bpf_prog_iops) + *type = BPF_TYPE_PROG; + else if (inode->i_op == &bpf_map_iops) + *type = BPF_TYPE_MAP; + else + return -EACCES; + + return 0; +} + +static bool bpf_dname_reserved(const struct dentry *dentry) +{ + return strchr(dentry->d_name.name, '.'); +} + +static int bpf_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) +{ + struct inode *inode; + + if (bpf_dname_reserved(dentry)) + return -EPERM; + + inode = bpf_get_inode(dir->i_sb, dir, mode | S_IFDIR); + if (IS_ERR(inode)) + return PTR_ERR(inode); + + inode->i_op = &bpf_dir_iops; + inode->i_fop = &simple_dir_operations; + + inc_nlink(inode); + inc_nlink(dir); + + d_instantiate(dentry, inode); + dget(dentry); + + return 0; +} + +static int bpf_mkobj_ops(struct inode *dir, struct dentry *dentry, + umode_t mode, const struct inode_operations *iops) +{ + struct inode *inode; + + if (bpf_dname_reserved(dentry)) + return -EPERM; + + inode = bpf_get_inode(dir->i_sb, dir, mode | S_IFREG); + if (IS_ERR(inode)) + return PTR_ERR(inode); + + inode->i_op = iops; + inode->i_private = dentry->d_fsdata; + + d_instantiate(dentry, inode); + dget(dentry); + + return 0; +} + +static int bpf_mkobj(struct inode *dir, struct dentry *dentry, umode_t mode, + dev_t devt) +{ + enum bpf_type type = MINOR(devt); + + if (MAJOR(devt) != UNNAMED_MAJOR || !S_ISREG(mode) || + dentry->d_fsdata == NULL) + return -EPERM; + + switch (type) { + case BPF_TYPE_PROG: + return bpf_mkobj_ops(dir, dentry, mode, &bpf_prog_iops); + case BPF_TYPE_MAP: + return bpf_mkobj_ops(dir, dentry, mode, &bpf_map_iops); + default: + return -EPERM; + } +} + +static const struct inode_operations bpf_dir_iops = { + .lookup = simple_lookup, + .mknod = bpf_mkobj, + .mkdir = bpf_mkdir, + .rmdir = simple_rmdir, + .unlink = simple_unlink, +}; + +static int bpf_obj_do_pin(const struct filename *pathname, void *raw, + enum bpf_type type) +{ + struct dentry *dentry; + struct inode *dir; + struct path path; + umode_t mode; + dev_t devt; + int ret; + + dentry = kern_path_create(AT_FDCWD, pathname->name, &path, 0); + if (IS_ERR(dentry)) + return PTR_ERR(dentry); + + mode = S_IFREG | ((S_IRUSR | S_IWUSR) & ~current_umask()); + devt = MKDEV(UNNAMED_MAJOR, type); + + ret = security_path_mknod(&path, dentry, mode, devt); + if (ret) + goto out; + + dir = d_inode(path.dentry); + if (dir->i_op != &bpf_dir_iops) { + ret = -EPERM; + goto out; + } + + dentry->d_fsdata = raw; + ret = vfs_mknod(dir, dentry, mode, devt); + dentry->d_fsdata = NULL; +out: + done_path_create(&path, dentry); + return ret; +} + +int bpf_obj_pin_user(u32 ufd, const char __user *pathname) +{ + struct filename *pname; + enum bpf_type type; + void *raw; + int ret; + + pname = getname(pathname); + if (IS_ERR(pname)) + return PTR_ERR(pname); + + raw = bpf_fd_probe_obj(ufd, &type); + if (IS_ERR(raw)) { + ret = PTR_ERR(raw); + goto out; + } + + ret = bpf_obj_do_pin(pname, raw, type); + if (ret != 0) + bpf_any_put(raw, type); +out: + putname(pname); + return ret; +} + +static void *bpf_obj_do_get(const struct filename *pathname, + enum bpf_type *type) +{ + struct inode *inode; + struct path path; + void *raw; + int ret; + + ret = kern_path(pathname->name, LOOKUP_FOLLOW, &path); + if (ret) + return ERR_PTR(ret); + + inode = d_backing_inode(path.dentry); + ret = inode_permission(inode, MAY_WRITE); + if (ret) + goto out; + + ret = bpf_inode_type(inode, type); + if (ret) + goto out; + + raw = bpf_any_get(inode->i_private, *type); + touch_atime(&path); + + path_put(&path); + return raw; +out: + path_put(&path); + return ERR_PTR(ret); +} + +int bpf_obj_get_user(const char __user *pathname) +{ + enum bpf_type type = BPF_TYPE_UNSPEC; + struct filename *pname; + int ret = -ENOENT; + void *raw; + + pname = getname(pathname); + if (IS_ERR(pname)) + return PTR_ERR(pname); + + raw = bpf_obj_do_get(pname, &type); + if (IS_ERR(raw)) { + ret = PTR_ERR(raw); + goto out; + } + + if (type == BPF_TYPE_PROG) + ret = bpf_prog_new_fd(raw); + else if (type == BPF_TYPE_MAP) + ret = bpf_map_new_fd(raw); + else + goto out; + + if (ret < 0) + bpf_any_put(raw, type); +out: + putname(pname); + return ret; +} + +static void bpf_evict_inode(struct inode *inode) +{ + enum bpf_type type; + + truncate_inode_pages_final(&inode->i_data); + clear_inode(inode); + + if (!bpf_inode_type(inode, &type)) + bpf_any_put(inode->i_private, type); +} + +static const struct super_operations bpf_super_ops = { + .statfs = simple_statfs, + .drop_inode = generic_delete_inode, + .evict_inode = bpf_evict_inode, +}; + +static int bpf_fill_super(struct super_block *sb, void *data, int silent) +{ + static struct tree_descr bpf_rfiles[] = { { "" } }; + struct inode *inode; + int ret; + + ret = simple_fill_super(sb, BPF_FS_MAGIC, bpf_rfiles); + if (ret) + return ret; + + sb->s_op = &bpf_super_ops; + + inode = sb->s_root->d_inode; + inode->i_op = &bpf_dir_iops; + inode->i_mode &= ~S_IALLUGO; + inode->i_mode |= S_ISVTX | S_IRWXUGO; + + return 0; +} + +static struct dentry *bpf_mount(struct file_system_type *type, int flags, + const char *dev_name, void *data) +{ + return mount_ns(type, flags, current->nsproxy->mnt_ns, bpf_fill_super); +} + +static struct file_system_type bpf_fs_type = { + .owner = THIS_MODULE, + .name = "bpf", + .mount = bpf_mount, + .kill_sb = kill_litter_super, + .fs_flags = FS_USERNS_MOUNT, +}; + +MODULE_ALIAS_FS("bpf"); + +static int __init bpf_init(void) +{ + int ret; + + ret = sysfs_create_mount_point(fs_kobj, "bpf"); + if (ret) + return ret; + + ret = register_filesystem(&bpf_fs_type); + if (ret) + sysfs_remove_mount_point(fs_kobj, "bpf"); + + return ret; +} +fs_initcall(bpf_init); diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 35bac8e8b071..0d3313d02a7e 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -18,6 +18,8 @@ #include <linux/filter.h> #include <linux/version.h> +int sysctl_unprivileged_bpf_disabled __read_mostly; + static LIST_HEAD(bpf_map_types); static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) @@ -44,11 +46,38 @@ void bpf_register_map_type(struct bpf_map_type_list *tl) list_add(&tl->list_node, &bpf_map_types); } +static int bpf_map_charge_memlock(struct bpf_map *map) +{ + struct user_struct *user = get_current_user(); + unsigned long memlock_limit; + + memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; + + atomic_long_add(map->pages, &user->locked_vm); + + if (atomic_long_read(&user->locked_vm) > memlock_limit) { + atomic_long_sub(map->pages, &user->locked_vm); + free_uid(user); + return -EPERM; + } + map->user = user; + return 0; +} + +static void bpf_map_uncharge_memlock(struct bpf_map *map) +{ + struct user_struct *user = map->user; + + atomic_long_sub(map->pages, &user->locked_vm); + free_uid(user); +} + /* called from workqueue */ static void bpf_map_free_deferred(struct work_struct *work) { struct bpf_map *map = container_of(work, struct bpf_map, work); + bpf_map_uncharge_memlock(map); /* implementation dependent freeing */ map->ops->map_free(map); } @@ -82,6 +111,12 @@ static const struct file_operations bpf_map_fops = { .release = bpf_map_release, }; +int bpf_map_new_fd(struct bpf_map *map) +{ + return anon_inode_getfd("bpf-map", &bpf_map_fops, map, + O_RDWR | O_CLOEXEC); +} + /* helper macro to check that unused fields 'union bpf_attr' are zero */ #define CHECK_ATTR(CMD) \ memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ @@ -108,8 +143,11 @@ static int map_create(union bpf_attr *attr) atomic_set(&map->refcnt, 1); - err = anon_inode_getfd("bpf-map", &bpf_map_fops, map, O_RDWR | O_CLOEXEC); + err = bpf_map_charge_memlock(map); + if (err) + goto free_map; + err = bpf_map_new_fd(map); if (err < 0) /* failed to allocate fd */ goto free_map; @@ -124,19 +162,29 @@ free_map: /* if error is returned, fd is released. * On success caller should complete fd access with matching fdput() */ -struct bpf_map *bpf_map_get(struct fd f) +struct bpf_map *__bpf_map_get(struct fd f) { - struct bpf_map *map; - if (!f.file) return ERR_PTR(-EBADF); - if (f.file->f_op != &bpf_map_fops) { fdput(f); return ERR_PTR(-EINVAL); } - map = f.file->private_data; + return f.file->private_data; +} + +struct bpf_map *bpf_map_get(u32 ufd) +{ + struct fd f = fdget(ufd); + struct bpf_map *map; + + map = __bpf_map_get(f); + if (IS_ERR(map)) + return map; + + atomic_inc(&map->refcnt); + fdput(f); return map; } @@ -164,7 +212,7 @@ static int map_lookup_elem(union bpf_attr *attr) return -EINVAL; f = fdget(ufd); - map = bpf_map_get(f); + map = __bpf_map_get(f); if (IS_ERR(map)) return PTR_ERR(map); @@ -223,7 +271,7 @@ static int map_update_elem(union bpf_attr *attr) return -EINVAL; f = fdget(ufd); - map = bpf_map_get(f); + map = __bpf_map_get(f); if (IS_ERR(map)) return PTR_ERR(map); @@ -276,7 +324,7 @@ static int map_delete_elem(union bpf_attr *attr) return -EINVAL; f = fdget(ufd); - map = bpf_map_get(f); + map = __bpf_map_get(f); if (IS_ERR(map)) return PTR_ERR(map); @@ -317,7 +365,7 @@ static int map_get_next_key(union bpf_attr *attr) return -EINVAL; f = fdget(ufd); - map = bpf_map_get(f); + map = __bpf_map_get(f); if (IS_ERR(map)) return PTR_ERR(map); @@ -402,6 +450,10 @@ static void fixup_bpf_calls(struct bpf_prog *prog) */ BUG_ON(!prog->aux->ops->get_func_proto); + if (insn->imm == BPF_FUNC_get_route_realm) + prog->dst_needed = 1; + if (insn->imm == BPF_FUNC_get_prandom_u32) + bpf_user_rnd_init_once(); if (insn->imm == BPF_FUNC_tail_call) { /* mark bpf_tail_call as different opcode * to avoid conditional branch in @@ -436,29 +488,51 @@ static void free_used_maps(struct bpf_prog_aux *aux) kfree(aux->used_maps); } -static void __prog_put_rcu(struct rcu_head *rcu) +static int bpf_prog_charge_memlock(struct bpf_prog *prog) +{ + struct user_struct *user = get_current_user(); + unsigned long memlock_limit; + + memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; + + atomic_long_add(prog->pages, &user->locked_vm); + if (atomic_long_read(&user->locked_vm) > memlock_limit) { + atomic_long_sub(prog->pages, &user->locked_vm); + free_uid(user); + return -EPERM; + } + prog->aux->user = user; + return 0; +} + +static void bpf_prog_uncharge_memlock(struct bpf_prog *prog) +{ + struct user_struct *user = prog->aux->user; + + atomic_long_sub(prog->pages, &user->locked_vm); + free_uid(user); +} + +static void __prog_put_common(struct rcu_head *rcu) { struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); free_used_maps(aux); + bpf_prog_uncharge_memlock(aux->prog); bpf_prog_free(aux->prog); } /* version of bpf_prog_put() that is called after a grace period */ void bpf_prog_put_rcu(struct bpf_prog *prog) { - if (atomic_dec_and_test(&prog->aux->refcnt)) { - prog->aux->prog = prog; - call_rcu(&prog->aux->rcu, __prog_put_rcu); - } + if (atomic_dec_and_test(&prog->aux->refcnt)) + call_rcu(&prog->aux->rcu, __prog_put_common); } void bpf_prog_put(struct bpf_prog *prog) { - if (atomic_dec_and_test(&prog->aux->refcnt)) { - free_used_maps(prog->aux); - bpf_prog_free(prog); - } + if (atomic_dec_and_test(&prog->aux->refcnt)) + __prog_put_common(&prog->aux->rcu); } EXPORT_SYMBOL_GPL(bpf_prog_put); @@ -474,21 +548,22 @@ static const struct file_operations bpf_prog_fops = { .release = bpf_prog_release, }; -static struct bpf_prog *get_prog(struct fd f) +int bpf_prog_new_fd(struct bpf_prog *prog) { - struct bpf_prog *prog; + return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, + O_RDWR | O_CLOEXEC); +} +static struct bpf_prog *__bpf_prog_get(struct fd f) +{ if (!f.file) return ERR_PTR(-EBADF); - if (f.file->f_op != &bpf_prog_fops) { fdput(f); return ERR_PTR(-EINVAL); } - prog = f.file->private_data; - - return prog; + return f.file->private_data; } /* called by sockets/tracing/seccomp before attaching program to an event @@ -499,13 +574,13 @@ struct bpf_prog *bpf_prog_get(u32 ufd) struct fd f = fdget(ufd); struct bpf_prog *prog; - prog = get_prog(f); - + prog = __bpf_prog_get(f); if (IS_ERR(prog)) return prog; atomic_inc(&prog->aux->refcnt); fdput(f); + return prog; } EXPORT_SYMBOL_GPL(bpf_prog_get); @@ -540,11 +615,18 @@ static int bpf_prog_load(union bpf_attr *attr) attr->kern_version != LINUX_VERSION_CODE) return -EINVAL; + if (type != BPF_PROG_TYPE_SOCKET_FILTER && !capable(CAP_SYS_ADMIN)) + return -EPERM; + /* plain bpf_prog allocation */ prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); if (!prog) return -ENOMEM; + err = bpf_prog_charge_memlock(prog); + if (err) + goto free_prog_nouncharge; + prog->len = attr->insn_cnt; err = -EFAULT; @@ -553,10 +635,10 @@ static int bpf_prog_load(union bpf_attr *attr) goto free_prog; prog->orig_prog = NULL; - prog->jited = false; + prog->jited = 0; atomic_set(&prog->aux->refcnt, 1); - prog->gpl_compatible = is_gpl; + prog->gpl_compatible = is_gpl ? 1 : 0; /* find program type: socket_filter vs tracing_filter */ err = find_prog_type(type, prog); @@ -576,7 +658,7 @@ static int bpf_prog_load(union bpf_attr *attr) if (err < 0) goto free_used_maps; - err = anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, O_RDWR | O_CLOEXEC); + err = bpf_prog_new_fd(prog); if (err < 0) /* failed to allocate fd */ goto free_used_maps; @@ -586,20 +668,36 @@ static int bpf_prog_load(union bpf_attr *attr) free_used_maps: free_used_maps(prog->aux); free_prog: + bpf_prog_uncharge_memlock(prog); +free_prog_nouncharge: bpf_prog_free(prog); return err; } +#define BPF_OBJ_LAST_FIELD bpf_fd + +static int bpf_obj_pin(const union bpf_attr *attr) +{ + if (CHECK_ATTR(BPF_OBJ)) + return -EINVAL; + + return bpf_obj_pin_user(attr->bpf_fd, u64_to_ptr(attr->pathname)); +} + +static int bpf_obj_get(const union bpf_attr *attr) +{ + if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0) + return -EINVAL; + + return bpf_obj_get_user(u64_to_ptr(attr->pathname)); +} + SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) { union bpf_attr attr = {}; int err; - /* the syscall is limited to root temporarily. This restriction will be - * lifted when security audit is clean. Note that eBPF+tracing must have - * this restriction, since it may pass kernel data to user space - */ - if (!capable(CAP_SYS_ADMIN)) + if (!capable(CAP_SYS_ADMIN) && sysctl_unprivileged_bpf_disabled) return -EPERM; if (!access_ok(VERIFY_READ, uattr, 1)) @@ -654,6 +752,12 @@ SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, siz case BPF_PROG_LOAD: err = bpf_prog_load(&attr); break; + case BPF_OBJ_PIN: + err = bpf_obj_pin(&attr); + break; + case BPF_OBJ_GET: + err = bpf_obj_get(&attr); + break; default: err = -EINVAL; break; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index b074b23000d6..c6073056badf 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -199,6 +199,7 @@ struct verifier_env { struct verifier_state_list **explored_states; /* search pruning optimization */ struct bpf_map *used_maps[MAX_USED_MAPS]; /* array of map's used by eBPF program */ u32 used_map_cnt; /* number of used maps */ + bool allow_ptr_leaks; }; /* verbose verifier prints what it's seeing @@ -213,7 +214,7 @@ static DEFINE_MUTEX(bpf_verifier_lock); * verbose() is used to dump the verification trace to the log, so the user * can figure out what's wrong with the program */ -static void verbose(const char *fmt, ...) +static __printf(1, 2) void verbose(const char *fmt, ...) { va_list args; @@ -244,6 +245,7 @@ static const struct { } func_limit[] = { {BPF_MAP_TYPE_PROG_ARRAY, BPF_FUNC_tail_call}, {BPF_MAP_TYPE_PERF_EVENT_ARRAY, BPF_FUNC_perf_event_read}, + {BPF_MAP_TYPE_PERF_EVENT_ARRAY, BPF_FUNC_perf_event_output}, }; static void print_verifier_state(struct verifier_env *env) @@ -538,6 +540,21 @@ static int bpf_size_to_bytes(int bpf_size) return -EINVAL; } +static bool is_spillable_regtype(enum bpf_reg_type type) +{ + switch (type) { + case PTR_TO_MAP_VALUE: + case PTR_TO_MAP_VALUE_OR_NULL: + case PTR_TO_STACK: + case PTR_TO_CTX: + case FRAME_PTR: + case CONST_PTR_TO_MAP: + return true; + default: + return false; + } +} + /* check_stack_read/write functions track spill/fill of registers, * stack boundary and alignment are checked in check_mem_access() */ @@ -550,9 +567,7 @@ static int check_stack_write(struct verifier_state *state, int off, int size, */ if (value_regno >= 0 && - (state->regs[value_regno].type == PTR_TO_MAP_VALUE || - state->regs[value_regno].type == PTR_TO_STACK || - state->regs[value_regno].type == PTR_TO_CTX)) { + is_spillable_regtype(state->regs[value_regno].type)) { /* register containing pointer is being spilled into stack */ if (size != BPF_REG_SIZE) { @@ -643,6 +658,20 @@ static int check_ctx_access(struct verifier_env *env, int off, int size, return -EACCES; } +static bool is_pointer_value(struct verifier_env *env, int regno) +{ + if (env->allow_ptr_leaks) + return false; + + switch (env->cur_state.regs[regno].type) { + case UNKNOWN_VALUE: + case CONST_IMM: + return false; + default: + return true; + } +} + /* check whether memory at (regno + off) is accessible for t = (read | write) * if t==write, value_regno is a register which value is stored into memory * if t==read, value_regno is a register which will receive the value from memory @@ -669,11 +698,21 @@ static int check_mem_access(struct verifier_env *env, u32 regno, int off, } if (state->regs[regno].type == PTR_TO_MAP_VALUE) { + if (t == BPF_WRITE && value_regno >= 0 && + is_pointer_value(env, value_regno)) { + verbose("R%d leaks addr into map\n", value_regno); + return -EACCES; + } err = check_map_access(env, regno, off, size); if (!err && t == BPF_READ && value_regno >= 0) mark_reg_unknown_value(state->regs, value_regno); } else if (state->regs[regno].type == PTR_TO_CTX) { + if (t == BPF_WRITE && value_regno >= 0 && + is_pointer_value(env, value_regno)) { + verbose("R%d leaks addr into ctx\n", value_regno); + return -EACCES; + } err = check_ctx_access(env, off, size, t); if (!err && t == BPF_READ && value_regno >= 0) mark_reg_unknown_value(state->regs, value_regno); @@ -684,10 +723,17 @@ static int check_mem_access(struct verifier_env *env, u32 regno, int off, verbose("invalid stack off=%d size=%d\n", off, size); return -EACCES; } - if (t == BPF_WRITE) + if (t == BPF_WRITE) { + if (!env->allow_ptr_leaks && + state->stack_slot_type[MAX_BPF_STACK + off] == STACK_SPILL && + size != BPF_REG_SIZE) { + verbose("attempt to corrupt spilled pointer on stack\n"); + return -EACCES; + } err = check_stack_write(state, off, size, value_regno); - else + } else { err = check_stack_read(state, off, size, value_regno); + } } else { verbose("R%d invalid mem access '%s'\n", regno, reg_type_str[state->regs[regno].type]); @@ -775,8 +821,13 @@ static int check_func_arg(struct verifier_env *env, u32 regno, return -EACCES; } - if (arg_type == ARG_ANYTHING) + if (arg_type == ARG_ANYTHING) { + if (is_pointer_value(env, regno)) { + verbose("R%d leaks addr into helper function\n", regno); + return -EACCES; + } return 0; + } if (arg_type == ARG_PTR_TO_STACK || arg_type == ARG_PTR_TO_MAP_KEY || arg_type == ARG_PTR_TO_MAP_VALUE) { @@ -860,7 +911,7 @@ static int check_map_func_compatibility(struct bpf_map *map, int func_id) * don't allow any other map type to be passed into * the special func; */ - if (bool_map != bool_func) + if (bool_func && bool_map != bool_func) return -EINVAL; } @@ -950,8 +1001,9 @@ static int check_call(struct verifier_env *env, int func_id) } /* check validity of 32-bit and 64-bit arithmetic operations */ -static int check_alu_op(struct reg_state *regs, struct bpf_insn *insn) +static int check_alu_op(struct verifier_env *env, struct bpf_insn *insn) { + struct reg_state *regs = env->cur_state.regs; u8 opcode = BPF_OP(insn->code); int err; @@ -976,6 +1028,12 @@ static int check_alu_op(struct reg_state *regs, struct bpf_insn *insn) if (err) return err; + if (is_pointer_value(env, insn->dst_reg)) { + verbose("R%d pointer arithmetic prohibited\n", + insn->dst_reg); + return -EACCES; + } + /* check dest operand */ err = check_reg_arg(regs, insn->dst_reg, DST_OP); if (err) @@ -1012,6 +1070,11 @@ static int check_alu_op(struct reg_state *regs, struct bpf_insn *insn) */ regs[insn->dst_reg] = regs[insn->src_reg]; } else { + if (is_pointer_value(env, insn->src_reg)) { + verbose("R%d partial copy of pointer\n", + insn->src_reg); + return -EACCES; + } regs[insn->dst_reg].type = UNKNOWN_VALUE; regs[insn->dst_reg].map_ptr = NULL; } @@ -1061,8 +1124,18 @@ static int check_alu_op(struct reg_state *regs, struct bpf_insn *insn) /* pattern match 'bpf_add Rx, imm' instruction */ if (opcode == BPF_ADD && BPF_CLASS(insn->code) == BPF_ALU64 && regs[insn->dst_reg].type == FRAME_PTR && - BPF_SRC(insn->code) == BPF_K) + BPF_SRC(insn->code) == BPF_K) { stack_relative = true; + } else if (is_pointer_value(env, insn->dst_reg)) { + verbose("R%d pointer arithmetic prohibited\n", + insn->dst_reg); + return -EACCES; + } else if (BPF_SRC(insn->code) == BPF_X && + is_pointer_value(env, insn->src_reg)) { + verbose("R%d pointer arithmetic prohibited\n", + insn->src_reg); + return -EACCES; + } /* check dest operand */ err = check_reg_arg(regs, insn->dst_reg, DST_OP); @@ -1101,6 +1174,12 @@ static int check_cond_jmp_op(struct verifier_env *env, err = check_reg_arg(regs, insn->src_reg, SRC_OP); if (err) return err; + + if (is_pointer_value(env, insn->src_reg)) { + verbose("R%d pointer comparison prohibited\n", + insn->src_reg); + return -EACCES; + } } else { if (insn->src_reg != BPF_REG_0) { verbose("BPF_JMP uses reserved fields\n"); @@ -1155,6 +1234,9 @@ static int check_cond_jmp_op(struct verifier_env *env, regs[insn->dst_reg].type = CONST_IMM; regs[insn->dst_reg].imm = 0; } + } else if (is_pointer_value(env, insn->dst_reg)) { + verbose("R%d pointer comparison prohibited\n", insn->dst_reg); + return -EACCES; } else if (BPF_SRC(insn->code) == BPF_K && (opcode == BPF_JEQ || opcode == BPF_JNE)) { @@ -1658,7 +1740,7 @@ static int do_check(struct verifier_env *env) } if (class == BPF_ALU || class == BPF_ALU64) { - err = check_alu_op(regs, insn); + err = check_alu_op(env, insn); if (err) return err; @@ -1816,6 +1898,11 @@ static int do_check(struct verifier_env *env) if (err) return err; + if (is_pointer_value(env, BPF_REG_0)) { + verbose("R0 leaks addr as return value\n"); + return -EACCES; + } + process_bpf_exit: insn_idx = pop_stack(env, &prev_insn_idx); if (insn_idx < 0) { @@ -1902,8 +1989,7 @@ static int replace_map_fd_with_map_ptr(struct verifier_env *env) } f = fdget(insn->imm); - - map = bpf_map_get(f); + map = __bpf_map_get(f); if (IS_ERR(map)) { verbose("fd %d is not pointing to valid bpf_map\n", insn->imm); @@ -2024,7 +2110,7 @@ static int convert_ctx_accesses(struct verifier_env *env) cnt = env->prog->aux->ops-> convert_ctx_access(type, insn->dst_reg, insn->src_reg, - insn->off, insn_buf); + insn->off, insn_buf, env->prog); if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf)) { verbose("bpf verifier is misconfigured\n"); return -EINVAL; @@ -2144,6 +2230,8 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr) if (ret < 0) goto skip_full_check; + env->allow_ptr_leaks = capable(CAP_SYS_ADMIN); + ret = do_check(env); skip_full_check: diff --git a/kernel/cgroup.c b/kernel/cgroup.c index 2c9eae6ad970..f1603c153890 100644 --- a/kernel/cgroup.c +++ b/kernel/cgroup.c @@ -45,7 +45,7 @@ #include <linux/sched.h> #include <linux/slab.h> #include <linux/spinlock.h> -#include <linux/rwsem.h> +#include <linux/percpu-rwsem.h> #include <linux/string.h> #include <linux/sort.h> #include <linux/kmod.h> @@ -75,7 +75,7 @@ * cgroup_mutex is the master lock. Any modification to cgroup or its * hierarchy must be performed while holding it. * - * css_set_rwsem protects task->cgroups pointer, the list of css_set + * css_set_lock protects task->cgroups pointer, the list of css_set * objects, and the chain of tasks off each css_set. * * These locks are exported if CONFIG_PROVE_RCU so that accessors in @@ -83,12 +83,12 @@ */ #ifdef CONFIG_PROVE_RCU DEFINE_MUTEX(cgroup_mutex); -DECLARE_RWSEM(css_set_rwsem); +DEFINE_SPINLOCK(css_set_lock); EXPORT_SYMBOL_GPL(cgroup_mutex); -EXPORT_SYMBOL_GPL(css_set_rwsem); +EXPORT_SYMBOL_GPL(css_set_lock); #else static DEFINE_MUTEX(cgroup_mutex); -static DECLARE_RWSEM(css_set_rwsem); +static DEFINE_SPINLOCK(css_set_lock); #endif /* @@ -103,6 +103,8 @@ static DEFINE_SPINLOCK(cgroup_idr_lock); */ static DEFINE_SPINLOCK(release_agent_path_lock); +struct percpu_rw_semaphore cgroup_threadgroup_rwsem; + #define cgroup_assert_mutex_or_rcu_locked() \ RCU_LOCKDEP_WARN(!rcu_read_lock_held() && \ !lockdep_is_held(&cgroup_mutex), \ @@ -136,6 +138,27 @@ static const char *cgroup_subsys_name[] = { }; #undef SUBSYS +/* array of static_keys for cgroup_subsys_enabled() and cgroup_subsys_on_dfl() */ +#define SUBSYS(_x) \ + DEFINE_STATIC_KEY_TRUE(_x ## _cgrp_subsys_enabled_key); \ + DEFINE_STATIC_KEY_TRUE(_x ## _cgrp_subsys_on_dfl_key); \ + EXPORT_SYMBOL_GPL(_x ## _cgrp_subsys_enabled_key); \ + EXPORT_SYMBOL_GPL(_x ## _cgrp_subsys_on_dfl_key); +#include <linux/cgroup_subsys.h> +#undef SUBSYS + +#define SUBSYS(_x) [_x ## _cgrp_id] = &_x ## _cgrp_subsys_enabled_key, +static struct static_key_true *cgroup_subsys_enabled_key[] = { +#include <linux/cgroup_subsys.h> +}; +#undef SUBSYS + +#define SUBSYS(_x) [_x ## _cgrp_id] = &_x ## _cgrp_subsys_on_dfl_key, +static struct static_key_true *cgroup_subsys_on_dfl_key[] = { +#include <linux/cgroup_subsys.h> +}; +#undef SUBSYS + /* * The default hierarchy, reserved for the subsystems that are otherwise * unattached - it never has more than a single cgroup, and all tasks are @@ -150,12 +173,6 @@ EXPORT_SYMBOL_GPL(cgrp_dfl_root); */ static bool cgrp_dfl_root_visible; -/* - * Set by the boot param of the same name and makes subsystems with NULL - * ->dfl_files to use ->legacy_files on the default hierarchy. - */ -static bool cgroup_legacy_files_on_dfl; - /* some controllers are not supported in the default hierarchy */ static unsigned long cgrp_dfl_root_inhibit_ss_mask; @@ -183,6 +200,7 @@ static u64 css_serial_nr_next = 1; */ static unsigned long have_fork_callback __read_mostly; static unsigned long have_exit_callback __read_mostly; +static unsigned long have_free_callback __read_mostly; /* Ditto for the can_fork callback. */ static unsigned long have_canfork_callback __read_mostly; @@ -192,14 +210,87 @@ static struct cftype cgroup_legacy_base_files[]; static int rebind_subsystems(struct cgroup_root *dst_root, unsigned long ss_mask); +static void css_task_iter_advance(struct css_task_iter *it); static int cgroup_destroy_locked(struct cgroup *cgrp); static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss, bool visible); static void css_release(struct percpu_ref *ref); static void kill_css(struct cgroup_subsys_state *css); -static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[], +static int cgroup_addrm_files(struct cgroup_subsys_state *css, + struct cgroup *cgrp, struct cftype cfts[], bool is_add); +/** + * cgroup_ssid_enabled - cgroup subsys enabled test by subsys ID + * @ssid: subsys ID of interest + * + * cgroup_subsys_enabled() can only be used with literal subsys names which + * is fine for individual subsystems but unsuitable for cgroup core. This + * is slower static_key_enabled() based test indexed by @ssid. + */ +static bool cgroup_ssid_enabled(int ssid) +{ + return static_key_enabled(cgroup_subsys_enabled_key[ssid]); +} + +/** + * cgroup_on_dfl - test whether a cgroup is on the default hierarchy + * @cgrp: the cgroup of interest + * + * The default hierarchy is the v2 interface of cgroup and this function + * can be used to test whether a cgroup is on the default hierarchy for + * cases where a subsystem should behave differnetly depending on the + * interface version. + * + * The set of behaviors which change on the default hierarchy are still + * being determined and the mount option is prefixed with __DEVEL__. + * + * List of changed behaviors: + * + * - Mount options "noprefix", "xattr", "clone_children", "release_agent" + * and "name" are disallowed. + * + * - When mounting an existing superblock, mount options should match. + * + * - Remount is disallowed. + * + * - rename(2) is disallowed. + * + * - "tasks" is removed. Everything should be at process granularity. Use + * "cgroup.procs" instead. + * + * - "cgroup.procs" is not sorted. pids will be unique unless they got + * recycled inbetween reads. + * + * - "release_agent" and "notify_on_release" are removed. Replacement + * notification mechanism will be implemented. + * + * - "cgroup.clone_children" is removed. + * + * - "cgroup.subtree_populated" is available. Its value is 0 if the cgroup + * and its descendants contain no task; otherwise, 1. The file also + * generates kernfs notification which can be monitored through poll and + * [di]notify when the value of the file changes. + * + * - cpuset: tasks will be kept in empty cpusets when hotplug happens and + * take masks of ancestors with non-empty cpus/mems, instead of being + * moved to an ancestor. + * + * - cpuset: a task can be moved into an empty cpuset, and again it takes + * masks of ancestors. + * + * - memcg: use_hierarchy is on by default and the cgroup file for the flag + * is not created. + * + * - blkcg: blk-throttle becomes properly hierarchical. + * + * - debug: disallowed on the default hierarchy. + */ +static bool cgroup_on_dfl(const struct cgroup *cgrp) +{ + return cgrp->root == &cgrp_dfl_root; +} + /* IDR wrappers which synchronize using cgroup_idr_lock */ static int cgroup_idr_alloc(struct idr *idr, void *ptr, int start, int end, gfp_t gfp_mask) @@ -208,7 +299,7 @@ static int cgroup_idr_alloc(struct idr *idr, void *ptr, int start, int end, idr_preload(gfp_mask); spin_lock_bh(&cgroup_idr_lock); - ret = idr_alloc(idr, ptr, start, end, gfp_mask & ~__GFP_WAIT); + ret = idr_alloc(idr, ptr, start, end, gfp_mask & ~__GFP_DIRECT_RECLAIM); spin_unlock_bh(&cgroup_idr_lock); idr_preload_end(); return ret; @@ -332,6 +423,22 @@ static inline bool cgroup_is_dead(const struct cgroup *cgrp) return !(cgrp->self.flags & CSS_ONLINE); } +static void cgroup_get(struct cgroup *cgrp) +{ + WARN_ON_ONCE(cgroup_is_dead(cgrp)); + css_get(&cgrp->self); +} + +static bool cgroup_tryget(struct cgroup *cgrp) +{ + return css_tryget(&cgrp->self); +} + +static void cgroup_put(struct cgroup *cgrp) +{ + css_put(&cgrp->self); +} + struct cgroup_subsys_state *of_css(struct kernfs_open_file *of) { struct cgroup *cgrp = of->kn->parent->priv; @@ -481,19 +588,31 @@ struct css_set init_css_set = { .mg_tasks = LIST_HEAD_INIT(init_css_set.mg_tasks), .mg_preload_node = LIST_HEAD_INIT(init_css_set.mg_preload_node), .mg_node = LIST_HEAD_INIT(init_css_set.mg_node), + .task_iters = LIST_HEAD_INIT(init_css_set.task_iters), }; static int css_set_count = 1; /* 1 for init_css_set */ /** + * css_set_populated - does a css_set contain any tasks? + * @cset: target css_set + */ +static bool css_set_populated(struct css_set *cset) +{ + lockdep_assert_held(&css_set_lock); + + return !list_empty(&cset->tasks) || !list_empty(&cset->mg_tasks); +} + +/** * cgroup_update_populated - updated populated count of a cgroup * @cgrp: the target cgroup * @populated: inc or dec populated count * - * @cgrp is either getting the first task (css_set) or losing the last. - * Update @cgrp->populated_cnt accordingly. The count is propagated - * towards root so that a given cgroup's populated_cnt is zero iff the - * cgroup and all its descendants are empty. + * One of the css_sets associated with @cgrp is either getting its first + * task or losing the last. Update @cgrp->populated_cnt accordingly. The + * count is propagated towards root so that a given cgroup's populated_cnt + * is zero iff the cgroup and all its descendants don't contain any tasks. * * @cgrp's interface file "cgroup.populated" is zero if * @cgrp->populated_cnt is zero and 1 otherwise. When @cgrp->populated_cnt @@ -503,7 +622,7 @@ static int css_set_count = 1; /* 1 for init_css_set */ */ static void cgroup_update_populated(struct cgroup *cgrp, bool populated) { - lockdep_assert_held(&css_set_rwsem); + lockdep_assert_held(&css_set_lock); do { bool trigger; @@ -516,12 +635,93 @@ static void cgroup_update_populated(struct cgroup *cgrp, bool populated) if (!trigger) break; - if (cgrp->populated_kn) - kernfs_notify(cgrp->populated_kn); + check_for_release(cgrp); + cgroup_file_notify(&cgrp->events_file); + cgrp = cgroup_parent(cgrp); } while (cgrp); } +/** + * css_set_update_populated - update populated state of a css_set + * @cset: target css_set + * @populated: whether @cset is populated or depopulated + * + * @cset is either getting the first task or losing the last. Update the + * ->populated_cnt of all associated cgroups accordingly. + */ +static void css_set_update_populated(struct css_set *cset, bool populated) +{ + struct cgrp_cset_link *link; + + lockdep_assert_held(&css_set_lock); + + list_for_each_entry(link, &cset->cgrp_links, cgrp_link) + cgroup_update_populated(link->cgrp, populated); +} + +/** + * css_set_move_task - move a task from one css_set to another + * @task: task being moved + * @from_cset: css_set @task currently belongs to (may be NULL) + * @to_cset: new css_set @task is being moved to (may be NULL) + * @use_mg_tasks: move to @to_cset->mg_tasks instead of ->tasks + * + * Move @task from @from_cset to @to_cset. If @task didn't belong to any + * css_set, @from_cset can be NULL. If @task is being disassociated + * instead of moved, @to_cset can be NULL. + * + * This function automatically handles populated_cnt updates and + * css_task_iter adjustments but the caller is responsible for managing + * @from_cset and @to_cset's reference counts. + */ +static void css_set_move_task(struct task_struct *task, + struct css_set *from_cset, struct css_set *to_cset, + bool use_mg_tasks) +{ + lockdep_assert_held(&css_set_lock); + + if (from_cset) { + struct css_task_iter *it, *pos; + + WARN_ON_ONCE(list_empty(&task->cg_list)); + + /* + * @task is leaving, advance task iterators which are + * pointing to it so that they can resume at the next + * position. Advancing an iterator might remove it from + * the list, use safe walk. See css_task_iter_advance*() + * for details. + */ + list_for_each_entry_safe(it, pos, &from_cset->task_iters, + iters_node) + if (it->task_pos == &task->cg_list) + css_task_iter_advance(it); + + list_del_init(&task->cg_list); + if (!css_set_populated(from_cset)) + css_set_update_populated(from_cset, false); + } else { + WARN_ON_ONCE(!list_empty(&task->cg_list)); + } + + if (to_cset) { + /* + * We are synchronized through cgroup_threadgroup_rwsem + * against PF_EXITING setting such that we can't race + * against cgroup_exit() changing the css_set to + * init_css_set and dropping the old one. + */ + WARN_ON_ONCE(task->flags & PF_EXITING); + + if (!css_set_populated(to_cset)) + css_set_update_populated(to_cset, true); + rcu_assign_pointer(task->cgroups, to_cset); + list_add_tail(&task->cg_list, use_mg_tasks ? &to_cset->mg_tasks : + &to_cset->tasks); + } +} + /* * hash table for cgroup groups. This improves the performance to find * an existing css_set. This hash doesn't (currently) take into @@ -549,7 +749,7 @@ static void put_css_set_locked(struct css_set *cset) struct cgroup_subsys *ss; int ssid; - lockdep_assert_held(&css_set_rwsem); + lockdep_assert_held(&css_set_lock); if (!atomic_dec_and_test(&cset->refcount)) return; @@ -561,17 +761,10 @@ static void put_css_set_locked(struct css_set *cset) css_set_count--; list_for_each_entry_safe(link, tmp_link, &cset->cgrp_links, cgrp_link) { - struct cgroup *cgrp = link->cgrp; - list_del(&link->cset_link); list_del(&link->cgrp_link); - - /* @cgrp can't go away while we're holding css_set_rwsem */ - if (list_empty(&cgrp->cset_links)) { - cgroup_update_populated(cgrp, false); - check_for_release(cgrp); - } - + if (cgroup_parent(link->cgrp)) + cgroup_put(link->cgrp); kfree(link); } @@ -588,9 +781,9 @@ static void put_css_set(struct css_set *cset) if (atomic_add_unless(&cset->refcount, -1, 1)) return; - down_write(&css_set_rwsem); + spin_lock_bh(&css_set_lock); put_css_set_locked(cset); - up_write(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); } /* @@ -779,15 +972,15 @@ static void link_css_set(struct list_head *tmp_links, struct css_set *cset, link->cset = cset; link->cgrp = cgrp; - if (list_empty(&cgrp->cset_links)) - cgroup_update_populated(cgrp, true); - list_move(&link->cset_link, &cgrp->cset_links); - /* - * Always add links to the tail of the list so that the list - * is sorted by order of hierarchy creation + * Always add links to the tail of the lists so that the lists are + * in choronological order. */ + list_move_tail(&link->cset_link, &cgrp->cset_links); list_add_tail(&link->cgrp_link, &cset->cgrp_links); + + if (cgroup_parent(cgrp)) + cgroup_get(cgrp); } /** @@ -813,11 +1006,11 @@ static struct css_set *find_css_set(struct css_set *old_cset, /* First see if we already have a cgroup group that matches * the desired set */ - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); cset = find_existing_css_set(old_cset, cgrp, template); if (cset) get_css_set(cset); - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); if (cset) return cset; @@ -838,13 +1031,14 @@ static struct css_set *find_css_set(struct css_set *old_cset, INIT_LIST_HEAD(&cset->mg_tasks); INIT_LIST_HEAD(&cset->mg_preload_node); INIT_LIST_HEAD(&cset->mg_node); + INIT_LIST_HEAD(&cset->task_iters); INIT_HLIST_NODE(&cset->hlist); /* Copy the set of subsystem state objects generated in * find_existing_css_set() */ memcpy(cset->subsys, template, sizeof(cset->subsys)); - down_write(&css_set_rwsem); + spin_lock_bh(&css_set_lock); /* Add reference counts and links from the new css_set. */ list_for_each_entry(link, &old_cset->cgrp_links, cgrp_link) { struct cgroup *c = link->cgrp; @@ -866,53 +1060,11 @@ static struct css_set *find_css_set(struct css_set *old_cset, list_add_tail(&cset->e_cset_node[ssid], &cset->subsys[ssid]->cgroup->e_csets[ssid]); - up_write(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); return cset; } -void cgroup_threadgroup_change_begin(struct task_struct *tsk) -{ - down_read(&tsk->signal->group_rwsem); -} - -void cgroup_threadgroup_change_end(struct task_struct *tsk) -{ - up_read(&tsk->signal->group_rwsem); -} - -/** - * threadgroup_lock - lock threadgroup - * @tsk: member task of the threadgroup to lock - * - * Lock the threadgroup @tsk belongs to. No new task is allowed to enter - * and member tasks aren't allowed to exit (as indicated by PF_EXITING) or - * change ->group_leader/pid. This is useful for cases where the threadgroup - * needs to stay stable across blockable operations. - * - * fork and exit explicitly call threadgroup_change_{begin|end}() for - * synchronization. While held, no new task will be added to threadgroup - * and no existing live task will have its PF_EXITING set. - * - * de_thread() does threadgroup_change_{begin|end}() when a non-leader - * sub-thread becomes a new leader. - */ -static void threadgroup_lock(struct task_struct *tsk) -{ - down_write(&tsk->signal->group_rwsem); -} - -/** - * threadgroup_unlock - unlock threadgroup - * @tsk: member task of the threadgroup to unlock - * - * Reverse threadgroup_lock(). - */ -static inline void threadgroup_unlock(struct task_struct *tsk) -{ - up_write(&tsk->signal->group_rwsem); -} - static struct cgroup_root *cgroup_root_from_kf(struct kernfs_root *kf_root) { struct cgroup *root_cgrp = kf_root->kn->priv; @@ -972,14 +1124,15 @@ static void cgroup_destroy_root(struct cgroup_root *root) * Release all the links from cset_links to this hierarchy's * root cgroup */ - down_write(&css_set_rwsem); + spin_lock_bh(&css_set_lock); list_for_each_entry_safe(link, tmp_link, &cgrp->cset_links, cset_link) { list_del(&link->cset_link); list_del(&link->cgrp_link); kfree(link); } - up_write(&css_set_rwsem); + + spin_unlock_bh(&css_set_lock); if (!list_empty(&root->root_list)) { list_del(&root->root_list); @@ -1001,7 +1154,7 @@ static struct cgroup *cset_cgroup_from_root(struct css_set *cset, struct cgroup *res = NULL; lockdep_assert_held(&cgroup_mutex); - lockdep_assert_held(&css_set_rwsem); + lockdep_assert_held(&css_set_lock); if (cset == &init_css_set) { res = &root->cgrp; @@ -1024,7 +1177,7 @@ static struct cgroup *cset_cgroup_from_root(struct css_set *cset, /* * Return the cgroup for "task" from the given hierarchy. Must be - * called with cgroup_mutex and css_set_rwsem held. + * called with cgroup_mutex and css_set_lock held. */ static struct cgroup *task_cgroup_from_root(struct task_struct *task, struct cgroup_root *root) @@ -1063,7 +1216,6 @@ static struct cgroup *task_cgroup_from_root(struct task_struct *task, * update of a tasks cgroup pointer by cgroup_attach_task() */ -static int cgroup_populate_dir(struct cgroup *cgrp, unsigned long subsys_mask); static struct kernfs_syscall_ops cgroup_kf_syscall_ops; static const struct file_operations proc_cgroupstats_operations; @@ -1086,43 +1238,25 @@ static char *cgroup_file_name(struct cgroup *cgrp, const struct cftype *cft, * cgroup_file_mode - deduce file mode of a control file * @cft: the control file in question * - * returns cft->mode if ->mode is not 0 - * returns S_IRUGO|S_IWUSR if it has both a read and a write handler - * returns S_IRUGO if it has only a read handler - * returns S_IWUSR if it has only a write hander + * S_IRUGO for read, S_IWUSR for write. */ static umode_t cgroup_file_mode(const struct cftype *cft) { umode_t mode = 0; - if (cft->mode) - return cft->mode; - if (cft->read_u64 || cft->read_s64 || cft->seq_show) mode |= S_IRUGO; - if (cft->write_u64 || cft->write_s64 || cft->write) - mode |= S_IWUSR; + if (cft->write_u64 || cft->write_s64 || cft->write) { + if (cft->flags & CFTYPE_WORLD_WRITABLE) + mode |= S_IWUGO; + else + mode |= S_IWUSR; + } return mode; } -static void cgroup_get(struct cgroup *cgrp) -{ - WARN_ON_ONCE(cgroup_is_dead(cgrp)); - css_get(&cgrp->self); -} - -static bool cgroup_tryget(struct cgroup *cgrp) -{ - return css_tryget(&cgrp->self); -} - -static void cgroup_put(struct cgroup *cgrp) -{ - css_put(&cgrp->self); -} - /** * cgroup_calc_child_subsys_mask - calculate child_subsys_mask * @cgrp: the target cgroup @@ -1263,28 +1397,64 @@ static void cgroup_rm_file(struct cgroup *cgrp, const struct cftype *cft) } /** - * cgroup_clear_dir - remove subsys files in a cgroup directory - * @cgrp: target cgroup - * @subsys_mask: mask of the subsystem ids whose files should be removed + * css_clear_dir - remove subsys files in a cgroup directory + * @css: taget css + * @cgrp_override: specify if target cgroup is different from css->cgroup */ -static void cgroup_clear_dir(struct cgroup *cgrp, unsigned long subsys_mask) +static void css_clear_dir(struct cgroup_subsys_state *css, + struct cgroup *cgrp_override) { - struct cgroup_subsys *ss; - int i; + struct cgroup *cgrp = cgrp_override ?: css->cgroup; + struct cftype *cfts; - for_each_subsys(ss, i) { - struct cftype *cfts; + list_for_each_entry(cfts, &css->ss->cfts, node) + cgroup_addrm_files(css, cgrp, cfts, false); +} - if (!(subsys_mask & (1 << i))) - continue; - list_for_each_entry(cfts, &ss->cfts, node) - cgroup_addrm_files(cgrp, cfts, false); +/** + * css_populate_dir - create subsys files in a cgroup directory + * @css: target css + * @cgrp_overried: specify if target cgroup is different from css->cgroup + * + * On failure, no file is added. + */ +static int css_populate_dir(struct cgroup_subsys_state *css, + struct cgroup *cgrp_override) +{ + struct cgroup *cgrp = cgrp_override ?: css->cgroup; + struct cftype *cfts, *failed_cfts; + int ret; + + if (!css->ss) { + if (cgroup_on_dfl(cgrp)) + cfts = cgroup_dfl_base_files; + else + cfts = cgroup_legacy_base_files; + + return cgroup_addrm_files(&cgrp->self, cgrp, cfts, true); + } + + list_for_each_entry(cfts, &css->ss->cfts, node) { + ret = cgroup_addrm_files(css, cgrp, cfts, true); + if (ret < 0) { + failed_cfts = cfts; + goto err; + } } + return 0; +err: + list_for_each_entry(cfts, &css->ss->cfts, node) { + if (cfts == failed_cfts) + break; + cgroup_addrm_files(css, cgrp, cfts, false); + } + return ret; } static int rebind_subsystems(struct cgroup_root *dst_root, unsigned long ss_mask) { + struct cgroup *dcgrp = &dst_root->cgrp; struct cgroup_subsys *ss; unsigned long tmp_ss_mask; int ssid, i, ret; @@ -1306,10 +1476,13 @@ static int rebind_subsystems(struct cgroup_root *dst_root, if (dst_root == &cgrp_dfl_root) tmp_ss_mask &= ~cgrp_dfl_root_inhibit_ss_mask; - ret = cgroup_populate_dir(&dst_root->cgrp, tmp_ss_mask); - if (ret) { - if (dst_root != &cgrp_dfl_root) - return ret; + for_each_subsys_which(ss, ssid, &tmp_ss_mask) { + struct cgroup *scgrp = &ss->root->cgrp; + int tssid; + + ret = css_populate_dir(cgroup_css(scgrp, ss), dcgrp); + if (!ret) + continue; /* * Rebinding back to the default root is not allowed to @@ -1317,57 +1490,67 @@ static int rebind_subsystems(struct cgroup_root *dst_root, * be rare. Moving subsystems back and forth even more so. * Just warn about it and continue. */ - if (cgrp_dfl_root_visible) { - pr_warn("failed to create files (%d) while rebinding 0x%lx to default root\n", - ret, ss_mask); - pr_warn("you may retry by moving them to a different hierarchy and unbinding\n"); + if (dst_root == &cgrp_dfl_root) { + if (cgrp_dfl_root_visible) { + pr_warn("failed to create files (%d) while rebinding 0x%lx to default root\n", + ret, ss_mask); + pr_warn("you may retry by moving them to a different hierarchy and unbinding\n"); + } + continue; + } + + for_each_subsys_which(ss, tssid, &tmp_ss_mask) { + if (tssid == ssid) + break; + css_clear_dir(cgroup_css(scgrp, ss), dcgrp); } + return ret; } /* * Nothing can fail from this point on. Remove files for the * removed subsystems and rebind each subsystem. */ - for_each_subsys_which(ss, ssid, &ss_mask) - cgroup_clear_dir(&ss->root->cgrp, 1 << ssid); - for_each_subsys_which(ss, ssid, &ss_mask) { - struct cgroup_root *src_root; - struct cgroup_subsys_state *css; + struct cgroup_root *src_root = ss->root; + struct cgroup *scgrp = &src_root->cgrp; + struct cgroup_subsys_state *css = cgroup_css(scgrp, ss); struct css_set *cset; - src_root = ss->root; - css = cgroup_css(&src_root->cgrp, ss); + WARN_ON(!css || cgroup_css(dcgrp, ss)); - WARN_ON(!css || cgroup_css(&dst_root->cgrp, ss)); + css_clear_dir(css, NULL); - RCU_INIT_POINTER(src_root->cgrp.subsys[ssid], NULL); - rcu_assign_pointer(dst_root->cgrp.subsys[ssid], css); + RCU_INIT_POINTER(scgrp->subsys[ssid], NULL); + rcu_assign_pointer(dcgrp->subsys[ssid], css); ss->root = dst_root; - css->cgroup = &dst_root->cgrp; + css->cgroup = dcgrp; - down_write(&css_set_rwsem); + spin_lock_bh(&css_set_lock); hash_for_each(css_set_table, i, cset, hlist) list_move_tail(&cset->e_cset_node[ss->id], - &dst_root->cgrp.e_csets[ss->id]); - up_write(&css_set_rwsem); + &dcgrp->e_csets[ss->id]); + spin_unlock_bh(&css_set_lock); src_root->subsys_mask &= ~(1 << ssid); - src_root->cgrp.subtree_control &= ~(1 << ssid); - cgroup_refresh_child_subsys_mask(&src_root->cgrp); + scgrp->subtree_control &= ~(1 << ssid); + cgroup_refresh_child_subsys_mask(scgrp); /* default hierarchy doesn't enable controllers by default */ dst_root->subsys_mask |= 1 << ssid; - if (dst_root != &cgrp_dfl_root) { - dst_root->cgrp.subtree_control |= 1 << ssid; - cgroup_refresh_child_subsys_mask(&dst_root->cgrp); + if (dst_root == &cgrp_dfl_root) { + static_branch_enable(cgroup_subsys_on_dfl_key[ssid]); + } else { + dcgrp->subtree_control |= 1 << ssid; + cgroup_refresh_child_subsys_mask(dcgrp); + static_branch_disable(cgroup_subsys_on_dfl_key[ssid]); } if (ss->bind) ss->bind(css); } - kernfs_activate(dst_root->cgrp.kn); + kernfs_activate(dcgrp->kn); return 0; } @@ -1497,7 +1680,7 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts) for_each_subsys(ss, i) { if (strcmp(token, ss->legacy_name)) continue; - if (ss->disabled) + if (!cgroup_ssid_enabled(i)) continue; /* Mutually exclusive option 'all' + subsystem name */ @@ -1528,7 +1711,7 @@ static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts) */ if (all_ss || (!one_ss && !opts->none && !opts->name)) for_each_subsys(ss, i) - if (!ss->disabled) + if (cgroup_ssid_enabled(i)) opts->subsys_mask |= (1 << i); /* @@ -1624,7 +1807,7 @@ static void cgroup_enable_task_cg_lists(void) { struct task_struct *p, *g; - down_write(&css_set_rwsem); + spin_lock_bh(&css_set_lock); if (use_task_css_set_links) goto out_unlock; @@ -1654,14 +1837,16 @@ static void cgroup_enable_task_cg_lists(void) if (!(p->flags & PF_EXITING)) { struct css_set *cset = task_css_set(p); - list_add(&p->cg_list, &cset->tasks); + if (!css_set_populated(cset)) + css_set_update_populated(cset, true); + list_add_tail(&p->cg_list, &cset->tasks); get_css_set(cset); } spin_unlock_irq(&p->sighand->siglock); } while_each_thread(g, p); read_unlock(&tasklist_lock); out_unlock: - up_write(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); } static void init_cgroup_housekeeping(struct cgroup *cgrp) @@ -1671,6 +1856,7 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp) INIT_LIST_HEAD(&cgrp->self.sibling); INIT_LIST_HEAD(&cgrp->self.children); + INIT_LIST_HEAD(&cgrp->self.files); INIT_LIST_HEAD(&cgrp->cset_links); INIT_LIST_HEAD(&cgrp->pidlists); mutex_init(&cgrp->pidlist_mutex); @@ -1708,7 +1894,6 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned long ss_mask) { LIST_HEAD(tmp_links); struct cgroup *root_cgrp = &root->cgrp; - struct cftype *base_files; struct css_set *cset; int i, ret; @@ -1725,7 +1910,7 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned long ss_mask) goto out; /* - * We're accessing css_set_count without locking css_set_rwsem here, + * We're accessing css_set_count without locking css_set_lock here, * but that's OK - it can only be increased by someone holding * cgroup_lock, and that's us. The worst that can happen is that we * have some link structures left over @@ -1747,12 +1932,7 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned long ss_mask) } root_cgrp->kn = root->kf_root->kn; - if (root == &cgrp_dfl_root) - base_files = cgroup_dfl_base_files; - else - base_files = cgroup_legacy_base_files; - - ret = cgroup_addrm_files(root_cgrp, base_files, true); + ret = css_populate_dir(&root_cgrp->self, NULL); if (ret) goto destroy_root; @@ -1772,10 +1952,13 @@ static int cgroup_setup_root(struct cgroup_root *root, unsigned long ss_mask) * Link the root cgroup in this hierarchy into all the css_set * objects. */ - down_write(&css_set_rwsem); - hash_for_each(css_set_table, i, cset, hlist) + spin_lock_bh(&css_set_lock); + hash_for_each(css_set_table, i, cset, hlist) { link_css_set(&tmp_links, cset, root_cgrp); - up_write(&css_set_rwsem); + if (css_set_populated(cset)) + cgroup_update_populated(root_cgrp, true); + } + spin_unlock_bh(&css_set_lock); BUG_ON(!list_empty(&root_cgrp->self.children)); BUG_ON(atomic_read(&root->nr_cgrps) != 1); @@ -2008,7 +2191,7 @@ char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen) char *path = NULL; mutex_lock(&cgroup_mutex); - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); root = idr_get_next(&cgroup_hierarchy_idr, &hierarchy_id); @@ -2021,7 +2204,7 @@ char *task_cgroup_path(struct task_struct *task, char *buf, size_t buflen) path = buf; } - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); mutex_unlock(&cgroup_mutex); return path; } @@ -2049,6 +2232,49 @@ struct cgroup_taskset { struct task_struct *cur_task; }; +#define CGROUP_TASKSET_INIT(tset) (struct cgroup_taskset){ \ + .src_csets = LIST_HEAD_INIT(tset.src_csets), \ + .dst_csets = LIST_HEAD_INIT(tset.dst_csets), \ + .csets = &tset.src_csets, \ +} + +/** + * cgroup_taskset_add - try to add a migration target task to a taskset + * @task: target task + * @tset: target taskset + * + * Add @task, which is a migration target, to @tset. This function becomes + * noop if @task doesn't need to be migrated. @task's css_set should have + * been added as a migration source and @task->cg_list will be moved from + * the css_set's tasks list to mg_tasks one. + */ +static void cgroup_taskset_add(struct task_struct *task, + struct cgroup_taskset *tset) +{ + struct css_set *cset; + + lockdep_assert_held(&css_set_lock); + + /* @task either already exited or can't exit until the end */ + if (task->flags & PF_EXITING) + return; + + /* leave @task alone if post_fork() hasn't linked it yet */ + if (list_empty(&task->cg_list)) + return; + + cset = task_css_set(task); + if (!cset->mg_src_cgrp) + return; + + list_move_tail(&task->cg_list, &cset->mg_tasks); + if (list_empty(&cset->mg_node)) + list_add_tail(&cset->mg_node, &tset->src_csets); + if (list_empty(&cset->mg_dst_cset->mg_node)) + list_move_tail(&cset->mg_dst_cset->mg_node, + &tset->dst_csets); +} + /** * cgroup_taskset_first - reset taskset and return the first task * @tset: taskset of interest @@ -2096,47 +2322,86 @@ struct task_struct *cgroup_taskset_next(struct cgroup_taskset *tset) } /** - * cgroup_task_migrate - move a task from one cgroup to another. - * @old_cgrp: the cgroup @tsk is being migrated from - * @tsk: the task being migrated - * @new_cset: the new css_set @tsk is being attached to + * cgroup_taskset_migrate - migrate a taskset to a cgroup + * @tset: taget taskset + * @dst_cgrp: destination cgroup * - * Must be called with cgroup_mutex, threadgroup and css_set_rwsem locked. + * Migrate tasks in @tset to @dst_cgrp. This function fails iff one of the + * ->can_attach callbacks fails and guarantees that either all or none of + * the tasks in @tset are migrated. @tset is consumed regardless of + * success. */ -static void cgroup_task_migrate(struct cgroup *old_cgrp, - struct task_struct *tsk, - struct css_set *new_cset) +static int cgroup_taskset_migrate(struct cgroup_taskset *tset, + struct cgroup *dst_cgrp) { - struct css_set *old_cset; - - lockdep_assert_held(&cgroup_mutex); - lockdep_assert_held(&css_set_rwsem); + struct cgroup_subsys_state *css, *failed_css = NULL; + struct task_struct *task, *tmp_task; + struct css_set *cset, *tmp_cset; + int i, ret; - /* - * We are synchronized through threadgroup_lock() against PF_EXITING - * setting such that we can't race against cgroup_exit() changing the - * css_set to init_css_set and dropping the old one. - */ - WARN_ON_ONCE(tsk->flags & PF_EXITING); - old_cset = task_css_set(tsk); + /* methods shouldn't be called if no task is actually migrating */ + if (list_empty(&tset->src_csets)) + return 0; - get_css_set(new_cset); - rcu_assign_pointer(tsk->cgroups, new_cset); + /* check that we can legitimately attach to the cgroup */ + for_each_e_css(css, i, dst_cgrp) { + if (css->ss->can_attach) { + ret = css->ss->can_attach(css, tset); + if (ret) { + failed_css = css; + goto out_cancel_attach; + } + } + } /* - * Use move_tail so that cgroup_taskset_first() still returns the - * leader after migration. This works because cgroup_migrate() - * ensures that the dst_cset of the leader is the first on the - * tset's dst_csets list. + * Now that we're guaranteed success, proceed to move all tasks to + * the new cgroup. There are no failure cases after here, so this + * is the commit point. */ - list_move_tail(&tsk->cg_list, &new_cset->mg_tasks); + spin_lock_bh(&css_set_lock); + list_for_each_entry(cset, &tset->src_csets, mg_node) { + list_for_each_entry_safe(task, tmp_task, &cset->mg_tasks, cg_list) { + struct css_set *from_cset = task_css_set(task); + struct css_set *to_cset = cset->mg_dst_cset; + + get_css_set(to_cset); + css_set_move_task(task, from_cset, to_cset, true); + put_css_set_locked(from_cset); + } + } + spin_unlock_bh(&css_set_lock); /* - * We just gained a reference on old_cset by taking it from the - * task. As trading it for new_cset is protected by cgroup_mutex, - * we're safe to drop it here; it will be freed under RCU. + * Migration is committed, all target tasks are now on dst_csets. + * Nothing is sensitive to fork() after this point. Notify + * controllers that migration is complete. */ - put_css_set_locked(old_cset); + tset->csets = &tset->dst_csets; + + for_each_e_css(css, i, dst_cgrp) + if (css->ss->attach) + css->ss->attach(css, tset); + + ret = 0; + goto out_release_tset; + +out_cancel_attach: + for_each_e_css(css, i, dst_cgrp) { + if (css == failed_css) + break; + if (css->ss->cancel_attach) + css->ss->cancel_attach(css, tset); + } +out_release_tset: + spin_lock_bh(&css_set_lock); + list_splice_init(&tset->dst_csets, &tset->src_csets); + list_for_each_entry_safe(cset, tmp_cset, &tset->src_csets, mg_node) { + list_splice_tail_init(&cset->mg_tasks, &cset->tasks); + list_del_init(&cset->mg_node); + } + spin_unlock_bh(&css_set_lock); + return ret; } /** @@ -2152,14 +2417,14 @@ static void cgroup_migrate_finish(struct list_head *preloaded_csets) lockdep_assert_held(&cgroup_mutex); - down_write(&css_set_rwsem); + spin_lock_bh(&css_set_lock); list_for_each_entry_safe(cset, tmp_cset, preloaded_csets, mg_preload_node) { cset->mg_src_cgrp = NULL; cset->mg_dst_cset = NULL; list_del_init(&cset->mg_preload_node); put_css_set_locked(cset); } - up_write(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); } /** @@ -2172,10 +2437,11 @@ static void cgroup_migrate_finish(struct list_head *preloaded_csets) * @src_cset and add it to @preloaded_csets, which should later be cleaned * up by cgroup_migrate_finish(). * - * This function may be called without holding threadgroup_lock even if the - * target is a process. Threads may be created and destroyed but as long - * as cgroup_mutex is not dropped, no new css_set can be put into play and - * the preloaded css_sets are guaranteed to cover all migrations. + * This function may be called without holding cgroup_threadgroup_rwsem + * even if the target is a process. Threads may be created and destroyed + * but as long as cgroup_mutex is not dropped, no new css_set can be put + * into play and the preloaded css_sets are guaranteed to cover all + * migrations. */ static void cgroup_migrate_add_src(struct css_set *src_cset, struct cgroup *dst_cgrp, @@ -2184,7 +2450,7 @@ static void cgroup_migrate_add_src(struct css_set *src_cset, struct cgroup *src_cgrp; lockdep_assert_held(&cgroup_mutex); - lockdep_assert_held(&css_set_rwsem); + lockdep_assert_held(&css_set_lock); src_cgrp = cset_cgroup_from_root(src_cset, dst_cgrp->root); @@ -2273,12 +2539,12 @@ err: /** * cgroup_migrate - migrate a process or task to a cgroup - * @cgrp: the destination cgroup * @leader: the leader of the process or the task to migrate * @threadgroup: whether @leader points to the whole process or a single task + * @cgrp: the destination cgroup * * Migrate a process or task denoted by @leader to @cgrp. If migrating a - * process, the caller must be holding threadgroup_lock of @leader. The + * process, the caller must be holding cgroup_threadgroup_rwsem. The * caller is also responsible for invoking cgroup_migrate_add_src() and * cgroup_migrate_prepare_dst() on the targets before invoking this * function and following up with cgroup_migrate_finish(). @@ -2289,115 +2555,29 @@ err: * decided for all targets by invoking group_migrate_prepare_dst() before * actually starting migrating. */ -static int cgroup_migrate(struct cgroup *cgrp, struct task_struct *leader, - bool threadgroup) -{ - struct cgroup_taskset tset = { - .src_csets = LIST_HEAD_INIT(tset.src_csets), - .dst_csets = LIST_HEAD_INIT(tset.dst_csets), - .csets = &tset.src_csets, - }; - struct cgroup_subsys_state *css, *failed_css = NULL; - struct css_set *cset, *tmp_cset; - struct task_struct *task, *tmp_task; - int i, ret; +static int cgroup_migrate(struct task_struct *leader, bool threadgroup, + struct cgroup *cgrp) +{ + struct cgroup_taskset tset = CGROUP_TASKSET_INIT(tset); + struct task_struct *task; /* * Prevent freeing of tasks while we take a snapshot. Tasks that are * already PF_EXITING could be freed from underneath us unless we * take an rcu_read_lock. */ - down_write(&css_set_rwsem); + spin_lock_bh(&css_set_lock); rcu_read_lock(); task = leader; do { - /* @task either already exited or can't exit until the end */ - if (task->flags & PF_EXITING) - goto next; - - /* leave @task alone if post_fork() hasn't linked it yet */ - if (list_empty(&task->cg_list)) - goto next; - - cset = task_css_set(task); - if (!cset->mg_src_cgrp) - goto next; - - /* - * cgroup_taskset_first() must always return the leader. - * Take care to avoid disturbing the ordering. - */ - list_move_tail(&task->cg_list, &cset->mg_tasks); - if (list_empty(&cset->mg_node)) - list_add_tail(&cset->mg_node, &tset.src_csets); - if (list_empty(&cset->mg_dst_cset->mg_node)) - list_move_tail(&cset->mg_dst_cset->mg_node, - &tset.dst_csets); - next: + cgroup_taskset_add(task, &tset); if (!threadgroup) break; } while_each_thread(leader, task); rcu_read_unlock(); - up_write(&css_set_rwsem); - - /* methods shouldn't be called if no task is actually migrating */ - if (list_empty(&tset.src_csets)) - return 0; - - /* check that we can legitimately attach to the cgroup */ - for_each_e_css(css, i, cgrp) { - if (css->ss->can_attach) { - ret = css->ss->can_attach(css, &tset); - if (ret) { - failed_css = css; - goto out_cancel_attach; - } - } - } - - /* - * Now that we're guaranteed success, proceed to move all tasks to - * the new cgroup. There are no failure cases after here, so this - * is the commit point. - */ - down_write(&css_set_rwsem); - list_for_each_entry(cset, &tset.src_csets, mg_node) { - list_for_each_entry_safe(task, tmp_task, &cset->mg_tasks, cg_list) - cgroup_task_migrate(cset->mg_src_cgrp, task, - cset->mg_dst_cset); - } - up_write(&css_set_rwsem); - - /* - * Migration is committed, all target tasks are now on dst_csets. - * Nothing is sensitive to fork() after this point. Notify - * controllers that migration is complete. - */ - tset.csets = &tset.dst_csets; - - for_each_e_css(css, i, cgrp) - if (css->ss->attach) - css->ss->attach(css, &tset); - - ret = 0; - goto out_release_tset; + spin_unlock_bh(&css_set_lock); -out_cancel_attach: - for_each_e_css(css, i, cgrp) { - if (css == failed_css) - break; - if (css->ss->cancel_attach) - css->ss->cancel_attach(css, &tset); - } -out_release_tset: - down_write(&css_set_rwsem); - list_splice_init(&tset.dst_csets, &tset.src_csets); - list_for_each_entry_safe(cset, tmp_cset, &tset.src_csets, mg_node) { - list_splice_tail_init(&cset->mg_tasks, &cset->tasks); - list_del_init(&cset->mg_node); - } - up_write(&css_set_rwsem); - return ret; + return cgroup_taskset_migrate(&tset, cgrp); } /** @@ -2406,7 +2586,7 @@ out_release_tset: * @leader: the task or the leader of the threadgroup to be attached * @threadgroup: attach the whole threadgroup? * - * Call holding cgroup_mutex and threadgroup_lock of @leader. + * Call holding cgroup_mutex and cgroup_threadgroup_rwsem. */ static int cgroup_attach_task(struct cgroup *dst_cgrp, struct task_struct *leader, bool threadgroup) @@ -2416,7 +2596,7 @@ static int cgroup_attach_task(struct cgroup *dst_cgrp, int ret; /* look up all src csets */ - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); rcu_read_lock(); task = leader; do { @@ -2426,12 +2606,12 @@ static int cgroup_attach_task(struct cgroup *dst_cgrp, break; } while_each_thread(leader, task); rcu_read_unlock(); - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); /* prepare dst csets and commit */ ret = cgroup_migrate_prepare_dst(dst_cgrp, &preloaded_csets); if (!ret) - ret = cgroup_migrate(dst_cgrp, leader, threadgroup); + ret = cgroup_migrate(leader, threadgroup, dst_cgrp); cgroup_migrate_finish(&preloaded_csets); return ret; @@ -2459,15 +2639,15 @@ static int cgroup_procs_write_permission(struct task_struct *task, struct cgroup *cgrp; struct inode *inode; - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); cgrp = task_cgroup_from_root(task, &cgrp_dfl_root); - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); while (!cgroup_is_descendant(dst_cgrp, cgrp)) cgrp = cgroup_parent(cgrp); ret = -ENOMEM; - inode = kernfs_get_inode(sb, cgrp->procs_kn); + inode = kernfs_get_inode(sb, cgrp->procs_file.kn); if (inode) { ret = inode_permission(inode, MAY_WRITE); iput(inode); @@ -2498,14 +2678,13 @@ static ssize_t __cgroup_procs_write(struct kernfs_open_file *of, char *buf, if (!cgrp) return -ENODEV; -retry_find_task: + percpu_down_write(&cgroup_threadgroup_rwsem); rcu_read_lock(); if (pid) { tsk = find_task_by_vpid(pid); if (!tsk) { - rcu_read_unlock(); ret = -ESRCH; - goto out_unlock_cgroup; + goto out_unlock_rcu; } } else { tsk = current; @@ -2521,37 +2700,23 @@ retry_find_task: */ if (tsk == kthreadd_task || (tsk->flags & PF_NO_SETAFFINITY)) { ret = -EINVAL; - rcu_read_unlock(); - goto out_unlock_cgroup; + goto out_unlock_rcu; } get_task_struct(tsk); rcu_read_unlock(); - threadgroup_lock(tsk); - if (threadgroup) { - if (!thread_group_leader(tsk)) { - /* - * a race with de_thread from another thread's exec() - * may strip us of our leadership, if this happens, - * there is no choice but to throw this task away and - * try again; this is - * "double-double-toil-and-trouble-check locking". - */ - threadgroup_unlock(tsk); - put_task_struct(tsk); - goto retry_find_task; - } - } - ret = cgroup_procs_write_permission(tsk, cgrp, of); if (!ret) ret = cgroup_attach_task(cgrp, tsk, threadgroup); - threadgroup_unlock(tsk); - put_task_struct(tsk); -out_unlock_cgroup: + goto out_unlock_threadgroup; + +out_unlock_rcu: + rcu_read_unlock(); +out_unlock_threadgroup: + percpu_up_write(&cgroup_threadgroup_rwsem); cgroup_kn_unlock(of->kn); return ret ?: nbytes; } @@ -2573,9 +2738,9 @@ int cgroup_attach_task_all(struct task_struct *from, struct task_struct *tsk) if (root == &cgrp_dfl_root) continue; - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); from_cgrp = task_cgroup_from_root(from, root); - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); retval = cgroup_attach_task(from_cgrp, tsk, false); if (retval) @@ -2690,14 +2855,17 @@ static int cgroup_subtree_control_show(struct seq_file *seq, void *v) static int cgroup_update_dfl_csses(struct cgroup *cgrp) { LIST_HEAD(preloaded_csets); + struct cgroup_taskset tset = CGROUP_TASKSET_INIT(tset); struct cgroup_subsys_state *css; struct css_set *src_cset; int ret; lockdep_assert_held(&cgroup_mutex); + percpu_down_write(&cgroup_threadgroup_rwsem); + /* look up all csses currently attached to @cgrp's subtree */ - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); css_for_each_descendant_pre(css, cgroup_css(cgrp, NULL)) { struct cgrp_cset_link *link; @@ -2709,68 +2877,31 @@ static int cgroup_update_dfl_csses(struct cgroup *cgrp) cgroup_migrate_add_src(link->cset, cgrp, &preloaded_csets); } - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); /* NULL dst indicates self on default hierarchy */ ret = cgroup_migrate_prepare_dst(NULL, &preloaded_csets); if (ret) goto out_finish; + spin_lock_bh(&css_set_lock); list_for_each_entry(src_cset, &preloaded_csets, mg_preload_node) { - struct task_struct *last_task = NULL, *task; + struct task_struct *task, *ntask; /* src_csets precede dst_csets, break on the first dst_cset */ if (!src_cset->mg_src_cgrp) break; - /* - * All tasks in src_cset need to be migrated to the - * matching dst_cset. Empty it process by process. We - * walk tasks but migrate processes. The leader might even - * belong to a different cset but such src_cset would also - * be among the target src_csets because the default - * hierarchy enforces per-process membership. - */ - while (true) { - down_read(&css_set_rwsem); - task = list_first_entry_or_null(&src_cset->tasks, - struct task_struct, cg_list); - if (task) { - task = task->group_leader; - WARN_ON_ONCE(!task_css_set(task)->mg_src_cgrp); - get_task_struct(task); - } - up_read(&css_set_rwsem); - - if (!task) - break; - - /* guard against possible infinite loop */ - if (WARN(last_task == task, - "cgroup: update_dfl_csses failed to make progress, aborting in inconsistent state\n")) - goto out_finish; - last_task = task; - - threadgroup_lock(task); - /* raced against de_thread() from another thread? */ - if (!thread_group_leader(task)) { - threadgroup_unlock(task); - put_task_struct(task); - continue; - } - - ret = cgroup_migrate(src_cset->dfl_cgrp, task, true); - - threadgroup_unlock(task); - put_task_struct(task); - - if (WARN(ret, "cgroup: failed to update controllers for the default hierarchy (%d), further operations may crash or hang\n", ret)) - goto out_finish; - } + /* all tasks in src_csets need to be migrated */ + list_for_each_entry_safe(task, ntask, &src_cset->tasks, cg_list) + cgroup_taskset_add(task, &tset); } + spin_unlock_bh(&css_set_lock); + ret = cgroup_taskset_migrate(&tset, cgrp); out_finish: cgroup_migrate_finish(&preloaded_csets); + percpu_up_write(&cgroup_threadgroup_rwsem); return ret; } @@ -2797,7 +2928,8 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of, if (tok[0] == '\0') continue; for_each_subsys_which(ss, ssid, &tmp_ss_mask) { - if (ss->disabled || strcmp(tok + 1, ss->name)) + if (!cgroup_ssid_enabled(ssid) || + strcmp(tok + 1, ss->name)) continue; if (*tok == '+') { @@ -2921,7 +3053,8 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of, ret = create_css(child, ss, cgrp->subtree_control & (1 << ssid)); else - ret = cgroup_populate_dir(child, 1 << ssid); + ret = css_populate_dir(cgroup_css(child, ss), + NULL); if (ret) goto err_undo_css; } @@ -2954,7 +3087,7 @@ static ssize_t cgroup_subtree_control_write(struct kernfs_open_file *of, if (css_disable & (1 << ssid)) { kill_css(css); } else { - cgroup_clear_dir(child, 1 << ssid); + css_clear_dir(css, NULL); if (ss->css_reset) ss->css_reset(css); } @@ -3002,15 +3135,16 @@ err_undo_css: if (css_enable & (1 << ssid)) kill_css(css); else - cgroup_clear_dir(child, 1 << ssid); + css_clear_dir(css, NULL); } } goto out_unlock; } -static int cgroup_populated_show(struct seq_file *seq, void *v) +static int cgroup_events_show(struct seq_file *seq, void *v) { - seq_printf(seq, "%d\n", (bool)seq_css(seq)->cgroup->populated_cnt); + seq_printf(seq, "populated %d\n", + cgroup_is_populated(seq_css(seq)->cgroup)); return 0; } @@ -3153,7 +3287,8 @@ static int cgroup_kn_set_ugid(struct kernfs_node *kn) return kernfs_setattr(kn, &iattr); } -static int cgroup_add_file(struct cgroup *cgrp, struct cftype *cft) +static int cgroup_add_file(struct cgroup_subsys_state *css, struct cgroup *cgrp, + struct cftype *cft) { char name[CGROUP_FILE_NAME_MAX]; struct kernfs_node *kn; @@ -3175,33 +3310,38 @@ static int cgroup_add_file(struct cgroup *cgrp, struct cftype *cft) return ret; } - if (cft->write == cgroup_procs_write) - cgrp->procs_kn = kn; - else if (cft->seq_show == cgroup_populated_show) - cgrp->populated_kn = kn; + if (cft->file_offset) { + struct cgroup_file *cfile = (void *)css + cft->file_offset; + + kernfs_get(kn); + cfile->kn = kn; + list_add(&cfile->node, &css->files); + } + return 0; } /** * cgroup_addrm_files - add or remove files to a cgroup directory - * @cgrp: the target cgroup + * @css: the target css + * @cgrp: the target cgroup (usually css->cgroup) * @cfts: array of cftypes to be added * @is_add: whether to add or remove * * Depending on @is_add, add or remove files defined by @cfts on @cgrp. - * For removals, this function never fails. If addition fails, this - * function doesn't remove files already added. The caller is responsible - * for cleaning up. + * For removals, this function never fails. */ -static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[], +static int cgroup_addrm_files(struct cgroup_subsys_state *css, + struct cgroup *cgrp, struct cftype cfts[], bool is_add) { - struct cftype *cft; + struct cftype *cft, *cft_end = NULL; int ret; lockdep_assert_held(&cgroup_mutex); - for (cft = cfts; cft->name[0] != '\0'; cft++) { +restart: + for (cft = cfts; cft != cft_end && cft->name[0] != '\0'; cft++) { /* does cft->flags tell us to skip this file on @cgrp? */ if ((cft->flags & __CFTYPE_ONLY_ON_DFL) && !cgroup_on_dfl(cgrp)) continue; @@ -3213,11 +3353,13 @@ static int cgroup_addrm_files(struct cgroup *cgrp, struct cftype cfts[], continue; if (is_add) { - ret = cgroup_add_file(cgrp, cft); + ret = cgroup_add_file(css, cgrp, cft); if (ret) { pr_warn("%s: failed to add %s, err=%d\n", __func__, cft->name, ret); - return ret; + cft_end = cft; + is_add = false; + goto restart; } } else { cgroup_rm_file(cgrp, cft); @@ -3243,7 +3385,7 @@ static int cgroup_apply_cftypes(struct cftype *cfts, bool is_add) if (cgroup_is_dead(cgrp)) continue; - ret = cgroup_addrm_files(cgrp, cfts, is_add); + ret = cgroup_addrm_files(css, cgrp, cfts, is_add); if (ret) break; } @@ -3355,7 +3497,7 @@ static int cgroup_add_cftypes(struct cgroup_subsys *ss, struct cftype *cfts) { int ret; - if (ss->disabled) + if (!cgroup_ssid_enabled(ss->id)) return 0; if (!cfts || cfts[0].name[0] == '\0') @@ -3405,17 +3547,8 @@ int cgroup_add_legacy_cftypes(struct cgroup_subsys *ss, struct cftype *cfts) { struct cftype *cft; - /* - * If legacy_flies_on_dfl, we want to show the legacy files on the - * dfl hierarchy but iff the target subsystem hasn't been updated - * for the dfl hierarchy yet. - */ - if (!cgroup_legacy_files_on_dfl || - ss->dfl_cftypes != ss->legacy_cftypes) { - for (cft = cfts; cft && cft->name[0] != '\0'; cft++) - cft->flags |= __CFTYPE_NOT_ON_DFL; - } - + for (cft = cfts; cft && cft->name[0] != '\0'; cft++) + cft->flags |= __CFTYPE_NOT_ON_DFL; return cgroup_add_cftypes(ss, cfts); } @@ -3430,10 +3563,10 @@ static int cgroup_task_count(const struct cgroup *cgrp) int count = 0; struct cgrp_cset_link *link; - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); list_for_each_entry(link, &cgrp->cset_links, cset_link) count += atomic_read(&link->cset->refcount); - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); return count; } @@ -3665,22 +3798,25 @@ bool css_has_online_children(struct cgroup_subsys_state *css) } /** - * css_advance_task_iter - advance a task itererator to the next css_set + * css_task_iter_advance_css_set - advance a task itererator to the next css_set * @it: the iterator to advance * * Advance @it to the next css_set to walk. */ -static void css_advance_task_iter(struct css_task_iter *it) +static void css_task_iter_advance_css_set(struct css_task_iter *it) { struct list_head *l = it->cset_pos; struct cgrp_cset_link *link; struct css_set *cset; + lockdep_assert_held(&css_set_lock); + /* Advance to the next non-empty css_set */ do { l = l->next; if (l == it->cset_head) { it->cset_pos = NULL; + it->task_pos = NULL; return; } @@ -3691,7 +3827,7 @@ static void css_advance_task_iter(struct css_task_iter *it) link = list_entry(l, struct cgrp_cset_link, cset_link); cset = link->cset; } - } while (list_empty(&cset->tasks) && list_empty(&cset->mg_tasks)); + } while (!css_set_populated(cset)); it->cset_pos = l; @@ -3702,6 +3838,52 @@ static void css_advance_task_iter(struct css_task_iter *it) it->tasks_head = &cset->tasks; it->mg_tasks_head = &cset->mg_tasks; + + /* + * We don't keep css_sets locked across iteration steps and thus + * need to take steps to ensure that iteration can be resumed after + * the lock is re-acquired. Iteration is performed at two levels - + * css_sets and tasks in them. + * + * Once created, a css_set never leaves its cgroup lists, so a + * pinned css_set is guaranteed to stay put and we can resume + * iteration afterwards. + * + * Tasks may leave @cset across iteration steps. This is resolved + * by registering each iterator with the css_set currently being + * walked and making css_set_move_task() advance iterators whose + * next task is leaving. + */ + if (it->cur_cset) { + list_del(&it->iters_node); + put_css_set_locked(it->cur_cset); + } + get_css_set(cset); + it->cur_cset = cset; + list_add(&it->iters_node, &cset->task_iters); +} + +static void css_task_iter_advance(struct css_task_iter *it) +{ + struct list_head *l = it->task_pos; + + lockdep_assert_held(&css_set_lock); + WARN_ON_ONCE(!l); + + /* + * Advance iterator to find next entry. cset->tasks is consumed + * first and then ->mg_tasks. After ->mg_tasks, we move onto the + * next cset. + */ + l = l->next; + + if (l == it->tasks_head) + l = it->mg_tasks_head->next; + + if (l == it->mg_tasks_head) + css_task_iter_advance_css_set(it); + else + it->task_pos = l; } /** @@ -3713,19 +3895,16 @@ static void css_advance_task_iter(struct css_task_iter *it) * css_task_iter_next() to walk through the tasks until the function * returns NULL. On completion of iteration, css_task_iter_end() must be * called. - * - * Note that this function acquires a lock which is released when the - * iteration finishes. The caller can't sleep while iteration is in - * progress. */ void css_task_iter_start(struct cgroup_subsys_state *css, struct css_task_iter *it) - __acquires(css_set_rwsem) { /* no one should try to iterate before mounting cgroups */ WARN_ON_ONCE(!use_task_css_set_links); - down_read(&css_set_rwsem); + memset(it, 0, sizeof(*it)); + + spin_lock_bh(&css_set_lock); it->ss = css->ss; @@ -3736,7 +3915,9 @@ void css_task_iter_start(struct cgroup_subsys_state *css, it->cset_head = it->cset_pos; - css_advance_task_iter(it); + css_task_iter_advance_css_set(it); + + spin_unlock_bh(&css_set_lock); } /** @@ -3749,30 +3930,23 @@ void css_task_iter_start(struct cgroup_subsys_state *css, */ struct task_struct *css_task_iter_next(struct css_task_iter *it) { - struct task_struct *res; - struct list_head *l = it->task_pos; + if (it->cur_task) { + put_task_struct(it->cur_task); + it->cur_task = NULL; + } - /* If the iterator cg is NULL, we have no tasks */ - if (!it->cset_pos) - return NULL; - res = list_entry(l, struct task_struct, cg_list); + spin_lock_bh(&css_set_lock); - /* - * Advance iterator to find next entry. cset->tasks is consumed - * first and then ->mg_tasks. After ->mg_tasks, we move onto the - * next cset. - */ - l = l->next; + if (it->task_pos) { + it->cur_task = list_entry(it->task_pos, struct task_struct, + cg_list); + get_task_struct(it->cur_task); + css_task_iter_advance(it); + } - if (l == it->tasks_head) - l = it->mg_tasks_head->next; + spin_unlock_bh(&css_set_lock); - if (l == it->mg_tasks_head) - css_advance_task_iter(it); - else - it->task_pos = l; - - return res; + return it->cur_task; } /** @@ -3782,9 +3956,16 @@ struct task_struct *css_task_iter_next(struct css_task_iter *it) * Finish task iteration started by css_task_iter_start(). */ void css_task_iter_end(struct css_task_iter *it) - __releases(css_set_rwsem) { - up_read(&css_set_rwsem); + if (it->cur_cset) { + spin_lock_bh(&css_set_lock); + list_del(&it->iters_node); + put_css_set_locked(it->cur_cset); + spin_unlock_bh(&css_set_lock); + } + + if (it->cur_task) + put_task_struct(it->cur_task); } /** @@ -3809,10 +3990,10 @@ int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from) mutex_lock(&cgroup_mutex); /* all tasks in @from are being moved, all csets are source */ - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); list_for_each_entry(link, &from->cset_links, cset_link) cgroup_migrate_add_src(link->cset, to, &preloaded_csets); - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); ret = cgroup_migrate_prepare_dst(to, &preloaded_csets); if (ret) @@ -3830,7 +4011,7 @@ int cgroup_transfer_tasks(struct cgroup *to, struct cgroup *from) css_task_iter_end(&it); if (task) { - ret = cgroup_migrate(to, task, false); + ret = cgroup_migrate(task, false, to); put_task_struct(task); } } while (task && !ret); @@ -4327,13 +4508,13 @@ static int cgroup_clone_children_write(struct cgroup_subsys_state *css, static struct cftype cgroup_dfl_base_files[] = { { .name = "cgroup.procs", + .file_offset = offsetof(struct cgroup, procs_file), .seq_start = cgroup_pidlist_start, .seq_next = cgroup_pidlist_next, .seq_stop = cgroup_pidlist_stop, .seq_show = cgroup_pidlist_show, .private = CGROUP_FILE_PROCS, .write = cgroup_procs_write, - .mode = S_IRUGO | S_IWUSR, }, { .name = "cgroup.controllers", @@ -4351,9 +4532,10 @@ static struct cftype cgroup_dfl_base_files[] = { .write = cgroup_subtree_control_write, }, { - .name = "cgroup.populated", + .name = "cgroup.events", .flags = CFTYPE_NOT_ON_ROOT, - .seq_show = cgroup_populated_show, + .file_offset = offsetof(struct cgroup, events_file), + .seq_show = cgroup_events_show, }, { } /* terminate */ }; @@ -4368,7 +4550,6 @@ static struct cftype cgroup_legacy_base_files[] = { .seq_show = cgroup_pidlist_show, .private = CGROUP_FILE_PROCS, .write = cgroup_procs_write, - .mode = S_IRUGO | S_IWUSR, }, { .name = "cgroup.clone_children", @@ -4388,7 +4569,6 @@ static struct cftype cgroup_legacy_base_files[] = { .seq_show = cgroup_pidlist_show, .private = CGROUP_FILE_TASKS, .write = cgroup_tasks_write, - .mode = S_IRUGO | S_IWUSR, }, { .name = "notify_on_release", @@ -4405,37 +4585,6 @@ static struct cftype cgroup_legacy_base_files[] = { { } /* terminate */ }; -/** - * cgroup_populate_dir - create subsys files in a cgroup directory - * @cgrp: target cgroup - * @subsys_mask: mask of the subsystem ids whose files should be added - * - * On failure, no file is added. - */ -static int cgroup_populate_dir(struct cgroup *cgrp, unsigned long subsys_mask) -{ - struct cgroup_subsys *ss; - int i, ret = 0; - - /* process cftsets of each subsystem */ - for_each_subsys(ss, i) { - struct cftype *cfts; - - if (!(subsys_mask & (1 << i))) - continue; - - list_for_each_entry(cfts, &ss->cfts, node) { - ret = cgroup_addrm_files(cgrp, cfts, true); - if (ret < 0) - goto err; - } - } - return 0; -err: - cgroup_clear_dir(cgrp, subsys_mask); - return ret; -} - /* * css destruction is four-stage process. * @@ -4464,9 +4613,13 @@ static void css_free_work_fn(struct work_struct *work) container_of(work, struct cgroup_subsys_state, destroy_work); struct cgroup_subsys *ss = css->ss; struct cgroup *cgrp = css->cgroup; + struct cgroup_file *cfile; percpu_ref_exit(&css->refcnt); + list_for_each_entry(cfile, &css->files, node) + kernfs_put(cfile->kn); + if (ss) { /* css free path */ int id = css->id; @@ -4571,6 +4724,7 @@ static void init_and_link_css(struct cgroup_subsys_state *css, css->ss = ss; INIT_LIST_HEAD(&css->sibling); INIT_LIST_HEAD(&css->children); + INIT_LIST_HEAD(&css->files); css->serial_nr = css_serial_nr_next++; if (cgroup_parent(cgrp)) { @@ -4653,7 +4807,7 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss, css->id = err; if (visible) { - err = cgroup_populate_dir(cgrp, 1 << ss->id); + err = css_populate_dir(css, NULL); if (err) goto err_free_id; } @@ -4679,7 +4833,7 @@ static int create_css(struct cgroup *cgrp, struct cgroup_subsys *ss, err_list_del: list_del_rcu(&css->sibling); - cgroup_clear_dir(css->cgroup, 1 << css->ss->id); + css_clear_dir(css, NULL); err_free_id: cgroup_idr_remove(&ss->css_idr, css->id); err_free_percpu_ref: @@ -4696,7 +4850,6 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, struct cgroup_root *root; struct cgroup_subsys *ss; struct kernfs_node *kn; - struct cftype *base_files; int ssid, ret; /* Do not accept '\n' to prevent making /proc/<pid>/cgroup unparsable. @@ -4772,12 +4925,7 @@ static int cgroup_mkdir(struct kernfs_node *parent_kn, const char *name, if (ret) goto out_destroy; - if (cgroup_on_dfl(cgrp)) - base_files = cgroup_dfl_base_files; - else - base_files = cgroup_legacy_base_files; - - ret = cgroup_addrm_files(cgrp, base_files, true); + ret = css_populate_dir(&cgrp->self, NULL); if (ret) goto out_destroy; @@ -4864,7 +5012,7 @@ static void kill_css(struct cgroup_subsys_state *css) * This must happen before css is disassociated with its cgroup. * See seq_css() for details. */ - cgroup_clear_dir(css->cgroup, 1 << css->ss->id); + css_clear_dir(css, NULL); /* * Killing would put the base ref, but we need to keep it alive @@ -4913,19 +5061,15 @@ static int cgroup_destroy_locked(struct cgroup *cgrp) __releases(&cgroup_mutex) __acquires(&cgroup_mutex) { struct cgroup_subsys_state *css; - bool empty; int ssid; lockdep_assert_held(&cgroup_mutex); /* - * css_set_rwsem synchronizes access to ->cset_links and prevents - * @cgrp from being removed while put_css_set() is in progress. + * Only migration can raise populated from zero and we're already + * holding cgroup_mutex. */ - down_read(&css_set_rwsem); - empty = list_empty(&cgrp->cset_links); - up_read(&css_set_rwsem); - if (!empty) + if (cgroup_is_populated(cgrp)) return -EBUSY; /* @@ -5023,6 +5167,7 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss, bool early) have_fork_callback |= (bool)ss->fork << ss->id; have_exit_callback |= (bool)ss->exit << ss->id; + have_free_callback |= (bool)ss->free << ss->id; have_canfork_callback |= (bool)ss->can_fork << ss->id; /* At system boot, before all subsystems have been @@ -5071,6 +5216,8 @@ int __init cgroup_init_early(void) return 0; } +static unsigned long cgroup_disable_mask __initdata; + /** * cgroup_init - cgroup initialization * @@ -5081,8 +5228,9 @@ int __init cgroup_init(void) { struct cgroup_subsys *ss; unsigned long key; - int ssid, err; + int ssid; + BUG_ON(percpu_init_rwsem(&cgroup_threadgroup_rwsem)); BUG_ON(cgroup_init_cftypes(NULL, cgroup_dfl_base_files)); BUG_ON(cgroup_init_cftypes(NULL, cgroup_legacy_base_files)); @@ -5116,14 +5264,15 @@ int __init cgroup_init(void) * disabled flag and cftype registration needs kmalloc, * both of which aren't available during early_init. */ - if (ss->disabled) + if (cgroup_disable_mask & (1 << ssid)) { + static_branch_disable(cgroup_subsys_enabled_key[ssid]); + printk(KERN_INFO "Disabling %s control group subsystem\n", + ss->name); continue; + } cgrp_dfl_root.subsys_mask |= 1 << ss->id; - if (cgroup_legacy_files_on_dfl && !ss->dfl_cftypes) - ss->dfl_cftypes = ss->legacy_cftypes; - if (!ss->dfl_cftypes) cgrp_dfl_root_inhibit_ss_mask |= 1 << ss->id; @@ -5138,17 +5287,10 @@ int __init cgroup_init(void) ss->bind(init_css_set.subsys[ssid]); } - err = sysfs_create_mount_point(fs_kobj, "cgroup"); - if (err) - return err; + WARN_ON(sysfs_create_mount_point(fs_kobj, "cgroup")); + WARN_ON(register_filesystem(&cgroup_fs_type)); + WARN_ON(!proc_create("cgroups", 0, NULL, &proc_cgroupstats_operations)); - err = register_filesystem(&cgroup_fs_type); - if (err < 0) { - sysfs_remove_mount_point(fs_kobj, "cgroup"); - return err; - } - - proc_create("cgroups", 0, NULL, &proc_cgroupstats_operations); return 0; } @@ -5195,7 +5337,7 @@ int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns, goto out; mutex_lock(&cgroup_mutex); - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); for_each_root(root) { struct cgroup_subsys *ss; @@ -5215,19 +5357,39 @@ int proc_cgroup_show(struct seq_file *m, struct pid_namespace *ns, seq_printf(m, "%sname=%s", count ? "," : "", root->name); seq_putc(m, ':'); + cgrp = task_cgroup_from_root(tsk, root); - path = cgroup_path(cgrp, buf, PATH_MAX); - if (!path) { - retval = -ENAMETOOLONG; - goto out_unlock; + + /* + * On traditional hierarchies, all zombie tasks show up as + * belonging to the root cgroup. On the default hierarchy, + * while a zombie doesn't show up in "cgroup.procs" and + * thus can't be migrated, its /proc/PID/cgroup keeps + * reporting the cgroup it belonged to before exiting. If + * the cgroup is removed before the zombie is reaped, + * " (deleted)" is appended to the cgroup path. + */ + if (cgroup_on_dfl(cgrp) || !(tsk->flags & PF_EXITING)) { + path = cgroup_path(cgrp, buf, PATH_MAX); + if (!path) { + retval = -ENAMETOOLONG; + goto out_unlock; + } + } else { + path = "/"; } + seq_puts(m, path); - seq_putc(m, '\n'); + + if (cgroup_on_dfl(cgrp) && cgroup_is_dead(cgrp)) + seq_puts(m, " (deleted)\n"); + else + seq_putc(m, '\n'); } retval = 0; out_unlock: - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); mutex_unlock(&cgroup_mutex); kfree(buf); out: @@ -5251,7 +5413,8 @@ static int proc_cgroupstats_show(struct seq_file *m, void *v) for_each_subsys(ss, i) seq_printf(m, "%s\t%d\t%d\t%d\n", ss->legacy_name, ss->root->hierarchy_id, - atomic_read(&ss->root->nr_cgrps), !ss->disabled); + atomic_read(&ss->root->nr_cgrps), + cgroup_ssid_enabled(i)); mutex_unlock(&cgroup_mutex); return 0; @@ -5372,7 +5535,7 @@ void cgroup_post_fork(struct task_struct *child, * @child during its iteration. * * If we won the race, @child is associated with %current's - * css_set. Grabbing css_set_rwsem guarantees both that the + * css_set. Grabbing css_set_lock guarantees both that the * association is stable, and, on completion of the parent's * migration, @child is visible in the source of migration or * already in the destination cgroup. This guarantee is necessary @@ -5387,14 +5550,13 @@ void cgroup_post_fork(struct task_struct *child, if (use_task_css_set_links) { struct css_set *cset; - down_write(&css_set_rwsem); + spin_lock_bh(&css_set_lock); cset = task_css_set(current); if (list_empty(&child->cg_list)) { - rcu_assign_pointer(child->cgroups, cset); - list_add(&child->cg_list, &cset->tasks); get_css_set(cset); + css_set_move_task(child, NULL, cset, false); } - up_write(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); } /* @@ -5429,39 +5591,42 @@ void cgroup_exit(struct task_struct *tsk) { struct cgroup_subsys *ss; struct css_set *cset; - bool put_cset = false; int i; /* * Unlink from @tsk from its css_set. As migration path can't race - * with us, we can check cg_list without grabbing css_set_rwsem. + * with us, we can check css_set and cg_list without synchronization. */ + cset = task_css_set(tsk); + if (!list_empty(&tsk->cg_list)) { - down_write(&css_set_rwsem); - list_del_init(&tsk->cg_list); - up_write(&css_set_rwsem); - put_cset = true; + spin_lock_bh(&css_set_lock); + css_set_move_task(tsk, cset, NULL, false); + spin_unlock_bh(&css_set_lock); + } else { + get_css_set(cset); } - /* Reassign the task to the init_css_set. */ - cset = task_css_set(tsk); - RCU_INIT_POINTER(tsk->cgroups, &init_css_set); - /* see cgroup_post_fork() for details */ - for_each_subsys_which(ss, i, &have_exit_callback) { - struct cgroup_subsys_state *old_css = cset->subsys[i]; - struct cgroup_subsys_state *css = task_css(tsk, i); + for_each_subsys_which(ss, i, &have_exit_callback) + ss->exit(tsk); +} - ss->exit(css, old_css, tsk); - } +void cgroup_free(struct task_struct *task) +{ + struct css_set *cset = task_css_set(task); + struct cgroup_subsys *ss; + int ssid; - if (put_cset) - put_css_set(cset); + for_each_subsys_which(ss, ssid, &have_free_callback) + ss->free(task); + + put_css_set(cset); } static void check_for_release(struct cgroup *cgrp) { - if (notify_on_release(cgrp) && !cgroup_has_tasks(cgrp) && + if (notify_on_release(cgrp) && !cgroup_is_populated(cgrp) && !css_has_online_children(&cgrp->self) && !cgroup_is_dead(cgrp)) schedule_work(&cgrp->release_agent_work); } @@ -5540,25 +5705,13 @@ static int __init cgroup_disable(char *str) if (strcmp(token, ss->name) && strcmp(token, ss->legacy_name)) continue; - - ss->disabled = 1; - printk(KERN_INFO "Disabling %s control group subsystem\n", - ss->name); - break; + cgroup_disable_mask |= 1 << i; } } return 1; } __setup("cgroup_disable=", cgroup_disable); -static int __init cgroup_set_legacy_files_on_dfl(char *str) -{ - printk("cgroup: using legacy files on the default hierarchy\n"); - cgroup_legacy_files_on_dfl = true; - return 0; -} -__setup("cgroup__DEVEL__legacy_files_on_dfl", cgroup_set_legacy_files_on_dfl); - /** * css_tryget_online_from_dir - get corresponding css from a cgroup dentry * @dentry: directory dentry of interest @@ -5662,7 +5815,7 @@ static int current_css_set_cg_links_read(struct seq_file *seq, void *v) if (!name_buf) return -ENOMEM; - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); rcu_read_lock(); cset = rcu_dereference(current->cgroups); list_for_each_entry(link, &cset->cgrp_links, cgrp_link) { @@ -5673,7 +5826,7 @@ static int current_css_set_cg_links_read(struct seq_file *seq, void *v) c->root->hierarchy_id, name_buf); } rcu_read_unlock(); - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); kfree(name_buf); return 0; } @@ -5684,7 +5837,7 @@ static int cgroup_css_links_read(struct seq_file *seq, void *v) struct cgroup_subsys_state *css = seq_css(seq); struct cgrp_cset_link *link; - down_read(&css_set_rwsem); + spin_lock_bh(&css_set_lock); list_for_each_entry(link, &css->cgroup->cset_links, cset_link) { struct css_set *cset = link->cset; struct task_struct *task; @@ -5707,13 +5860,13 @@ static int cgroup_css_links_read(struct seq_file *seq, void *v) overflow: seq_puts(seq, " ...\n"); } - up_read(&css_set_rwsem); + spin_unlock_bh(&css_set_lock); return 0; } static u64 releasable_read(struct cgroup_subsys_state *css, struct cftype *cft) { - return (!cgroup_has_tasks(css->cgroup) && + return (!cgroup_is_populated(css->cgroup) && !css_has_online_children(&css->cgroup->self)); } diff --git a/kernel/cgroup_pids.c b/kernel/cgroup_pids.c index 806cd7693ac8..cdd8df4e991c 100644 --- a/kernel/cgroup_pids.c +++ b/kernel/cgroup_pids.c @@ -266,11 +266,9 @@ static void pids_fork(struct task_struct *task, void *priv) css_put(old_css); } -static void pids_exit(struct cgroup_subsys_state *css, - struct cgroup_subsys_state *old_css, - struct task_struct *task) +static void pids_free(struct task_struct *task) { - struct pids_cgroup *pids = css_pids(old_css); + struct pids_cgroup *pids = css_pids(task_css(task, pids_cgrp_id)); pids_uncharge(pids, 1); } @@ -349,7 +347,7 @@ struct cgroup_subsys pids_cgrp_subsys = { .can_fork = pids_can_fork, .cancel_fork = pids_cancel_fork, .fork = pids_fork, - .exit = pids_exit, + .free = pids_free, .legacy_cftypes = pids_files, .dfl_cftypes = pids_files, }; diff --git a/kernel/cpu.c b/kernel/cpu.c index 82cf9dff4295..85ff5e26e23b 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -102,19 +102,6 @@ void get_online_cpus(void) } EXPORT_SYMBOL_GPL(get_online_cpus); -bool try_get_online_cpus(void) -{ - if (cpu_hotplug.active_writer == current) - return true; - if (!mutex_trylock(&cpu_hotplug.lock)) - return false; - cpuhp_lock_acquire_tryread(); - atomic_inc(&cpu_hotplug.refcount); - mutex_unlock(&cpu_hotplug.lock); - return true; -} -EXPORT_SYMBOL_GPL(try_get_online_cpus); - void put_online_cpus(void) { int refcount; @@ -304,8 +291,8 @@ static inline void check_for_tasks(int dead_cpu) { struct task_struct *g, *p; - read_lock_irq(&tasklist_lock); - do_each_thread(g, p) { + read_lock(&tasklist_lock); + for_each_process_thread(g, p) { if (!p->on_rq) continue; /* @@ -320,8 +307,8 @@ static inline void check_for_tasks(int dead_cpu) pr_warn("Task %s (pid=%d) is on cpu %d (state=%ld, flags=%x)\n", p->comm, task_pid_nr(p), dead_cpu, p->state, p->flags); - } while_each_thread(g, p); - read_unlock_irq(&tasklist_lock); + } + read_unlock(&tasklist_lock); } struct take_cpu_down_param { @@ -344,7 +331,7 @@ static int take_cpu_down(void *_param) /* Give up timekeeping duties */ tick_handover_do_timer(); /* Park the stopper thread */ - kthread_park(current); + stop_machine_park((long)param->hcpu); return 0; } diff --git a/kernel/cpuset.c b/kernel/cpuset.c index f0acff0f66c9..10ae73611d80 100644 --- a/kernel/cpuset.c +++ b/kernel/cpuset.c @@ -473,7 +473,8 @@ static int validate_change(struct cpuset *cur, struct cpuset *trial) /* On legacy hiearchy, we must be a subset of our parent cpuset. */ ret = -EACCES; - if (!cgroup_on_dfl(cur->css.cgroup) && !is_cpuset_subset(trial, par)) + if (!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && + !is_cpuset_subset(trial, par)) goto out; /* @@ -497,7 +498,7 @@ static int validate_change(struct cpuset *cur, struct cpuset *trial) * be changed to have empty cpus_allowed or mems_allowed. */ ret = -ENOSPC; - if ((cgroup_has_tasks(cur->css.cgroup) || cur->attach_in_progress)) { + if ((cgroup_is_populated(cur->css.cgroup) || cur->attach_in_progress)) { if (!cpumask_empty(cur->cpus_allowed) && cpumask_empty(trial->cpus_allowed)) goto out; @@ -879,7 +880,8 @@ static void update_cpumasks_hier(struct cpuset *cs, struct cpumask *new_cpus) * If it becomes empty, inherit the effective mask of the * parent, which is guaranteed to have some CPUs. */ - if (cgroup_on_dfl(cp->css.cgroup) && cpumask_empty(new_cpus)) + if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && + cpumask_empty(new_cpus)) cpumask_copy(new_cpus, parent->effective_cpus); /* Skip the whole subtree if the cpumask remains the same. */ @@ -896,7 +898,7 @@ static void update_cpumasks_hier(struct cpuset *cs, struct cpumask *new_cpus) cpumask_copy(cp->effective_cpus, new_cpus); spin_unlock_irq(&callback_lock); - WARN_ON(!cgroup_on_dfl(cp->css.cgroup) && + WARN_ON(!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && !cpumask_equal(cp->cpus_allowed, cp->effective_cpus)); update_tasks_cpumask(cp); @@ -1135,7 +1137,8 @@ static void update_nodemasks_hier(struct cpuset *cs, nodemask_t *new_mems) * If it becomes empty, inherit the effective mask of the * parent, which is guaranteed to have some MEMs. */ - if (cgroup_on_dfl(cp->css.cgroup) && nodes_empty(*new_mems)) + if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && + nodes_empty(*new_mems)) *new_mems = parent->effective_mems; /* Skip the whole subtree if the nodemask remains the same. */ @@ -1152,7 +1155,7 @@ static void update_nodemasks_hier(struct cpuset *cs, nodemask_t *new_mems) cp->effective_mems = *new_mems; spin_unlock_irq(&callback_lock); - WARN_ON(!cgroup_on_dfl(cp->css.cgroup) && + WARN_ON(!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && !nodes_equal(cp->mems_allowed, cp->effective_mems)); update_tasks_nodemask(cp); @@ -1440,7 +1443,7 @@ static int cpuset_can_attach(struct cgroup_subsys_state *css, /* allow moving tasks into an empty cpuset if on default hierarchy */ ret = -ENOSPC; - if (!cgroup_on_dfl(css->cgroup) && + if (!cgroup_subsys_on_dfl(cpuset_cgrp_subsys) && (cpumask_empty(cs->cpus_allowed) || nodes_empty(cs->mems_allowed))) goto out_unlock; @@ -1484,9 +1487,8 @@ static void cpuset_attach(struct cgroup_subsys_state *css, { /* static buf protected by cpuset_mutex */ static nodemask_t cpuset_attach_nodemask_to; - struct mm_struct *mm; struct task_struct *task; - struct task_struct *leader = cgroup_taskset_first(tset); + struct task_struct *leader; struct cpuset *cs = css_cs(css); struct cpuset *oldcs = cpuset_attach_old_cs; @@ -1512,26 +1514,30 @@ static void cpuset_attach(struct cgroup_subsys_state *css, } /* - * Change mm, possibly for multiple threads in a threadgroup. This is - * expensive and may sleep. + * Change mm for all threadgroup leaders. This is expensive and may + * sleep and should be moved outside migration path proper. */ cpuset_attach_nodemask_to = cs->effective_mems; - mm = get_task_mm(leader); - if (mm) { - mpol_rebind_mm(mm, &cpuset_attach_nodemask_to); - - /* - * old_mems_allowed is the same with mems_allowed here, except - * if this task is being moved automatically due to hotplug. - * In that case @mems_allowed has been updated and is empty, - * so @old_mems_allowed is the right nodesets that we migrate - * mm from. - */ - if (is_memory_migrate(cs)) { - cpuset_migrate_mm(mm, &oldcs->old_mems_allowed, - &cpuset_attach_nodemask_to); + cgroup_taskset_for_each_leader(leader, tset) { + struct mm_struct *mm = get_task_mm(leader); + + if (mm) { + mpol_rebind_mm(mm, &cpuset_attach_nodemask_to); + + /* + * old_mems_allowed is the same with mems_allowed + * here, except if this task is being moved + * automatically due to hotplug. In that case + * @mems_allowed has been updated and is empty, so + * @old_mems_allowed is the right nodesets that we + * migrate mm from. + */ + if (is_memory_migrate(cs)) { + cpuset_migrate_mm(mm, &oldcs->old_mems_allowed, + &cpuset_attach_nodemask_to); + } + mmput(mm); } - mmput(mm); } cs->old_mems_allowed = cpuset_attach_nodemask_to; @@ -1594,9 +1600,6 @@ static int cpuset_write_u64(struct cgroup_subsys_state *css, struct cftype *cft, case FILE_MEMORY_PRESSURE_ENABLED: cpuset_memory_pressure_enabled = !!val; break; - case FILE_MEMORY_PRESSURE: - retval = -EACCES; - break; case FILE_SPREAD_PAGE: retval = update_flag(CS_SPREAD_PAGE, cs, val); break; @@ -1863,9 +1866,6 @@ static struct cftype files[] = { { .name = "memory_pressure", .read_u64 = cpuset_read_u64, - .write_u64 = cpuset_write_u64, - .private = FILE_MEMORY_PRESSURE, - .mode = S_IRUGO, }, { @@ -1952,7 +1952,7 @@ static int cpuset_css_online(struct cgroup_subsys_state *css) cpuset_inc(); spin_lock_irq(&callback_lock); - if (cgroup_on_dfl(cs->css.cgroup)) { + if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) { cpumask_copy(cs->effective_cpus, parent->effective_cpus); cs->effective_mems = parent->effective_mems; } @@ -2029,7 +2029,7 @@ static void cpuset_bind(struct cgroup_subsys_state *root_css) mutex_lock(&cpuset_mutex); spin_lock_irq(&callback_lock); - if (cgroup_on_dfl(root_css->cgroup)) { + if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) { cpumask_copy(top_cpuset.cpus_allowed, cpu_possible_mask); top_cpuset.mems_allowed = node_possible_map; } else { @@ -2210,7 +2210,7 @@ retry: cpus_updated = !cpumask_equal(&new_cpus, cs->effective_cpus); mems_updated = !nodes_equal(new_mems, cs->effective_mems); - if (cgroup_on_dfl(cs->css.cgroup)) + if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) hotplug_update_tasks(cs, &new_cpus, &new_mems, cpus_updated, mems_updated); else @@ -2241,7 +2241,7 @@ static void cpuset_hotplug_workfn(struct work_struct *work) static cpumask_t new_cpus; static nodemask_t new_mems; bool cpus_updated, mems_updated; - bool on_dfl = cgroup_on_dfl(top_cpuset.css.cgroup); + bool on_dfl = cgroup_subsys_on_dfl(cpuset_cgrp_subsys); mutex_lock(&cpuset_mutex); @@ -2598,22 +2598,22 @@ int cpuset_mems_allowed_intersects(const struct task_struct *tsk1, } /** - * cpuset_print_task_mems_allowed - prints task's cpuset and mems_allowed - * @tsk: pointer to task_struct of some task. + * cpuset_print_current_mems_allowed - prints current's cpuset and mems_allowed * - * Description: Prints @task's name, cpuset name, and cached copy of its + * Description: Prints current's name, cpuset name, and cached copy of its * mems_allowed to the kernel log. */ -void cpuset_print_task_mems_allowed(struct task_struct *tsk) +void cpuset_print_current_mems_allowed(void) { struct cgroup *cgrp; rcu_read_lock(); - cgrp = task_cs(tsk)->css.cgroup; - pr_info("%s cpuset=", tsk->comm); + cgrp = task_cs(current)->css.cgroup; + pr_info("%s cpuset=", current->comm); pr_cont_cgroup_name(cgrp); - pr_cont(" mems_allowed=%*pbl\n", nodemask_pr_args(&tsk->mems_allowed)); + pr_cont(" mems_allowed=%*pbl\n", + nodemask_pr_args(¤t->mems_allowed)); rcu_read_unlock(); } diff --git a/kernel/events/core.c b/kernel/events/core.c index f548f69c4299..1a734e0adfa7 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -196,7 +196,7 @@ static int perf_sample_period_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS; static int perf_sample_allowed_ns __read_mostly = DEFAULT_SAMPLE_PERIOD_NS * DEFAULT_CPU_TIME_MAX_PERCENT / 100; -void update_perf_cpu_limits(void) +static void update_perf_cpu_limits(void) { u64 tmp = perf_sample_period_ns; @@ -472,7 +472,7 @@ perf_cgroup_set_timestamp(struct task_struct *task, * mode SWOUT : schedule out everything * mode SWIN : schedule in based on cgroup for next */ -void perf_cgroup_switch(struct task_struct *task, int mode) +static void perf_cgroup_switch(struct task_struct *task, int mode) { struct perf_cpu_context *cpuctx; struct pmu *pmu; @@ -1243,11 +1243,7 @@ static inline void perf_event__state_init(struct perf_event *event) PERF_EVENT_STATE_INACTIVE; } -/* - * Called at perf_event creation and when events are attached/detached from a - * group. - */ -static void perf_event__read_size(struct perf_event *event) +static void __perf_event_read_size(struct perf_event *event, int nr_siblings) { int entry = sizeof(u64); /* value */ int size = 0; @@ -1263,7 +1259,7 @@ static void perf_event__read_size(struct perf_event *event) entry += sizeof(u64); if (event->attr.read_format & PERF_FORMAT_GROUP) { - nr += event->group_leader->nr_siblings; + nr += nr_siblings; size += sizeof(u64); } @@ -1271,14 +1267,11 @@ static void perf_event__read_size(struct perf_event *event) event->read_size = size; } -static void perf_event__header_size(struct perf_event *event) +static void __perf_event_header_size(struct perf_event *event, u64 sample_type) { struct perf_sample_data *data; - u64 sample_type = event->attr.sample_type; u16 size = 0; - perf_event__read_size(event); - if (sample_type & PERF_SAMPLE_IP) size += sizeof(data->ip); @@ -1303,6 +1296,17 @@ static void perf_event__header_size(struct perf_event *event) event->header_size = size; } +/* + * Called at perf_event creation and when events are attached/detached from a + * group. + */ +static void perf_event__header_size(struct perf_event *event) +{ + __perf_event_read_size(event, + event->group_leader->nr_siblings); + __perf_event_header_size(event, event->attr.sample_type); +} + static void perf_event__id_header_size(struct perf_event *event) { struct perf_sample_data *data; @@ -1330,6 +1334,27 @@ static void perf_event__id_header_size(struct perf_event *event) event->id_header_size = size; } +static bool perf_event_validate_size(struct perf_event *event) +{ + /* + * The values computed here will be over-written when we actually + * attach the event. + */ + __perf_event_read_size(event, event->group_leader->nr_siblings + 1); + __perf_event_header_size(event, event->attr.sample_type & ~PERF_SAMPLE_READ); + perf_event__id_header_size(event); + + /* + * Sum the lot; should not exceed the 64k limit we have on records. + * Conservative limit to allow for callchains and other variable fields. + */ + if (event->read_size + event->header_size + + event->id_header_size + sizeof(struct perf_event_header) >= 16*1024) + return false; + + return true; +} + static void perf_group_attach(struct perf_event *event) { struct perf_event *group_leader = event->group_leader, *pos; @@ -1914,7 +1939,7 @@ group_sched_in(struct perf_event *group_event, if (group_event->state == PERF_EVENT_STATE_OFF) return 0; - pmu->start_txn(pmu); + pmu->start_txn(pmu, PERF_PMU_TXN_ADD); if (event_sched_in(group_event, cpuctx, ctx)) { pmu->cancel_txn(pmu); @@ -3184,14 +3209,22 @@ void perf_event_exec(void) rcu_read_unlock(); } +struct perf_read_data { + struct perf_event *event; + bool group; + int ret; +}; + /* * Cross CPU call to read the hardware event */ static void __perf_event_read(void *info) { - struct perf_event *event = info; + struct perf_read_data *data = info; + struct perf_event *sub, *event = data->event; struct perf_event_context *ctx = event->ctx; struct perf_cpu_context *cpuctx = __get_cpu_context(ctx); + struct pmu *pmu = event->pmu; /* * If this is a task context, we need to check whether it is @@ -3208,9 +3241,35 @@ static void __perf_event_read(void *info) update_context_time(ctx); update_cgrp_time_from_event(event); } + update_event_times(event); - if (event->state == PERF_EVENT_STATE_ACTIVE) - event->pmu->read(event); + if (event->state != PERF_EVENT_STATE_ACTIVE) + goto unlock; + + if (!data->group) { + pmu->read(event); + data->ret = 0; + goto unlock; + } + + pmu->start_txn(pmu, PERF_PMU_TXN_READ); + + pmu->read(event); + + list_for_each_entry(sub, &event->sibling_list, group_entry) { + update_event_times(sub); + if (sub->state == PERF_EVENT_STATE_ACTIVE) { + /* + * Use sibling's PMU rather than @event's since + * sibling could be on different (eg: software) PMU. + */ + sub->pmu->read(sub); + } + } + + data->ret = pmu->commit_txn(pmu); + +unlock: raw_spin_unlock(&ctx->lock); } @@ -3275,15 +3334,23 @@ u64 perf_event_read_local(struct perf_event *event) return val; } -static u64 perf_event_read(struct perf_event *event) +static int perf_event_read(struct perf_event *event, bool group) { + int ret = 0; + /* * If event is enabled and currently active on a CPU, update the * value in the event structure: */ if (event->state == PERF_EVENT_STATE_ACTIVE) { + struct perf_read_data data = { + .event = event, + .group = group, + .ret = 0, + }; smp_call_function_single(event->oncpu, - __perf_event_read, event, 1); + __perf_event_read, &data, 1); + ret = data.ret; } else if (event->state == PERF_EVENT_STATE_INACTIVE) { struct perf_event_context *ctx = event->ctx; unsigned long flags; @@ -3298,11 +3365,14 @@ static u64 perf_event_read(struct perf_event *event) update_context_time(ctx); update_cgrp_time_from_event(event); } - update_event_times(event); + if (group) + update_group_times(event); + else + update_event_times(event); raw_spin_unlock_irqrestore(&ctx->lock, flags); } - return perf_event_count(event); + return ret; } /* @@ -3744,7 +3814,7 @@ static void put_event(struct perf_event *event) * see the comment there. * * 2) there is a lock-inversion with mmap_sem through - * perf_event_read_group(), which takes faults while + * perf_read_group(), which takes faults while * holding ctx->mutex, however this is called after * the last filedesc died, so there is no possibility * to trigger the AB-BA case. @@ -3818,14 +3888,18 @@ u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) *running = 0; mutex_lock(&event->child_mutex); - total += perf_event_read(event); + + (void)perf_event_read(event, false); + total += perf_event_count(event); + *enabled += event->total_time_enabled + atomic64_read(&event->child_total_time_enabled); *running += event->total_time_running + atomic64_read(&event->child_total_time_running); list_for_each_entry(child, &event->child_list, child_list) { - total += perf_event_read(child); + (void)perf_event_read(child, false); + total += perf_event_count(child); *enabled += child->total_time_enabled; *running += child->total_time_running; } @@ -3835,55 +3909,95 @@ u64 perf_event_read_value(struct perf_event *event, u64 *enabled, u64 *running) } EXPORT_SYMBOL_GPL(perf_event_read_value); -static int perf_event_read_group(struct perf_event *event, - u64 read_format, char __user *buf) +static int __perf_read_group_add(struct perf_event *leader, + u64 read_format, u64 *values) { - struct perf_event *leader = event->group_leader, *sub; - struct perf_event_context *ctx = leader->ctx; - int n = 0, size = 0, ret; - u64 count, enabled, running; - u64 values[5]; + struct perf_event *sub; + int n = 1; /* skip @nr */ + int ret; - lockdep_assert_held(&ctx->mutex); + ret = perf_event_read(leader, true); + if (ret) + return ret; + + /* + * Since we co-schedule groups, {enabled,running} times of siblings + * will be identical to those of the leader, so we only publish one + * set. + */ + if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) { + values[n++] += leader->total_time_enabled + + atomic64_read(&leader->child_total_time_enabled); + } - count = perf_event_read_value(leader, &enabled, &running); + if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) { + values[n++] += leader->total_time_running + + atomic64_read(&leader->child_total_time_running); + } - values[n++] = 1 + leader->nr_siblings; - if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) - values[n++] = enabled; - if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) - values[n++] = running; - values[n++] = count; + /* + * Write {count,id} tuples for every sibling. + */ + values[n++] += perf_event_count(leader); if (read_format & PERF_FORMAT_ID) values[n++] = primary_event_id(leader); - size = n * sizeof(u64); + list_for_each_entry(sub, &leader->sibling_list, group_entry) { + values[n++] += perf_event_count(sub); + if (read_format & PERF_FORMAT_ID) + values[n++] = primary_event_id(sub); + } - if (copy_to_user(buf, values, size)) - return -EFAULT; + return 0; +} - ret = size; +static int perf_read_group(struct perf_event *event, + u64 read_format, char __user *buf) +{ + struct perf_event *leader = event->group_leader, *child; + struct perf_event_context *ctx = leader->ctx; + int ret; + u64 *values; - list_for_each_entry(sub, &leader->sibling_list, group_entry) { - n = 0; + lockdep_assert_held(&ctx->mutex); - values[n++] = perf_event_read_value(sub, &enabled, &running); - if (read_format & PERF_FORMAT_ID) - values[n++] = primary_event_id(sub); + values = kzalloc(event->read_size, GFP_KERNEL); + if (!values) + return -ENOMEM; - size = n * sizeof(u64); + values[0] = 1 + leader->nr_siblings; - if (copy_to_user(buf + ret, values, size)) { - return -EFAULT; - } + /* + * By locking the child_mutex of the leader we effectively + * lock the child list of all siblings.. XXX explain how. + */ + mutex_lock(&leader->child_mutex); - ret += size; + ret = __perf_read_group_add(leader, read_format, values); + if (ret) + goto unlock; + + list_for_each_entry(child, &leader->child_list, child_list) { + ret = __perf_read_group_add(child, read_format, values); + if (ret) + goto unlock; } + mutex_unlock(&leader->child_mutex); + + ret = event->read_size; + if (copy_to_user(buf, values, event->read_size)) + ret = -EFAULT; + goto out; + +unlock: + mutex_unlock(&leader->child_mutex); +out: + kfree(values); return ret; } -static int perf_event_read_one(struct perf_event *event, +static int perf_read_one(struct perf_event *event, u64 read_format, char __user *buf) { u64 enabled, running; @@ -3921,7 +4035,7 @@ static bool is_event_hup(struct perf_event *event) * Read the performance event - simple non blocking version for now */ static ssize_t -perf_read_hw(struct perf_event *event, char __user *buf, size_t count) +__perf_read(struct perf_event *event, char __user *buf, size_t count) { u64 read_format = event->attr.read_format; int ret; @@ -3939,9 +4053,9 @@ perf_read_hw(struct perf_event *event, char __user *buf, size_t count) WARN_ON_ONCE(event->ctx->parent_ctx); if (read_format & PERF_FORMAT_GROUP) - ret = perf_event_read_group(event, read_format, buf); + ret = perf_read_group(event, read_format, buf); else - ret = perf_event_read_one(event, read_format, buf); + ret = perf_read_one(event, read_format, buf); return ret; } @@ -3954,7 +4068,7 @@ perf_read(struct file *file, char __user *buf, size_t count, loff_t *ppos) int ret; ctx = perf_event_ctx_lock(event); - ret = perf_read_hw(event, buf, count); + ret = __perf_read(event, buf, count); perf_event_ctx_unlock(event, ctx); return ret; @@ -3985,7 +4099,7 @@ static unsigned int perf_poll(struct file *file, poll_table *wait) static void _perf_event_reset(struct perf_event *event) { - (void)perf_event_read(event); + (void)perf_event_read(event, false); local64_set(&event->count, 0); perf_event_update_userpage(event); } @@ -5261,9 +5375,15 @@ void perf_output_sample(struct perf_output_handle *handle, if (sample_type & PERF_SAMPLE_RAW) { if (data->raw) { - perf_output_put(handle, data->raw->size); - __output_copy(handle, data->raw->data, - data->raw->size); + u32 raw_size = data->raw->size; + u32 real_size = round_up(raw_size + sizeof(u32), + sizeof(u64)) - sizeof(u32); + u64 zero = 0; + + perf_output_put(handle, real_size); + __output_copy(handle, data->raw->data, raw_size); + if (real_size - raw_size) + __output_copy(handle, &zero, real_size - raw_size); } else { struct { u32 size; @@ -5395,8 +5515,7 @@ void perf_prepare_sample(struct perf_event_header *header, else size += sizeof(u32); - WARN_ON_ONCE(size & (sizeof(u64)-1)); - header->size += size; + header->size += round_up(size, sizeof(u64)); } if (sample_type & PERF_SAMPLE_BRANCH_STACK) { @@ -7267,24 +7386,49 @@ static void perf_pmu_nop_void(struct pmu *pmu) { } +static void perf_pmu_nop_txn(struct pmu *pmu, unsigned int flags) +{ +} + static int perf_pmu_nop_int(struct pmu *pmu) { return 0; } -static void perf_pmu_start_txn(struct pmu *pmu) +static DEFINE_PER_CPU(unsigned int, nop_txn_flags); + +static void perf_pmu_start_txn(struct pmu *pmu, unsigned int flags) { + __this_cpu_write(nop_txn_flags, flags); + + if (flags & ~PERF_PMU_TXN_ADD) + return; + perf_pmu_disable(pmu); } static int perf_pmu_commit_txn(struct pmu *pmu) { + unsigned int flags = __this_cpu_read(nop_txn_flags); + + __this_cpu_write(nop_txn_flags, 0); + + if (flags & ~PERF_PMU_TXN_ADD) + return 0; + perf_pmu_enable(pmu); return 0; } static void perf_pmu_cancel_txn(struct pmu *pmu) { + unsigned int flags = __this_cpu_read(nop_txn_flags); + + __this_cpu_write(nop_txn_flags, 0); + + if (flags & ~PERF_PMU_TXN_ADD) + return; + perf_pmu_enable(pmu); } @@ -7523,7 +7667,7 @@ got_cpu_context: pmu->commit_txn = perf_pmu_commit_txn; pmu->cancel_txn = perf_pmu_cancel_txn; } else { - pmu->start_txn = perf_pmu_nop_void; + pmu->start_txn = perf_pmu_nop_txn; pmu->commit_txn = perf_pmu_nop_int; pmu->cancel_txn = perf_pmu_nop_void; } @@ -7611,7 +7755,7 @@ static int perf_try_init_event(struct pmu *pmu, struct perf_event *event) return ret; } -struct pmu *perf_init_event(struct perf_event *event) +static struct pmu *perf_init_event(struct perf_event *event) { struct pmu *pmu = NULL; int idx; @@ -8297,13 +8441,35 @@ SYSCALL_DEFINE5(perf_event_open, if (move_group) { gctx = group_leader->ctx; + mutex_lock_double(&gctx->mutex, &ctx->mutex); + } else { + mutex_lock(&ctx->mutex); + } + + if (!perf_event_validate_size(event)) { + err = -E2BIG; + goto err_locked; + } + + /* + * Must be under the same ctx::mutex as perf_install_in_context(), + * because we need to serialize with concurrent event creation. + */ + if (!exclusive_event_installable(event, ctx)) { + /* exclusive and group stuff are assumed mutually exclusive */ + WARN_ON_ONCE(move_group); + err = -EBUSY; + goto err_locked; + } + + WARN_ON_ONCE(ctx->parent_ctx); + + if (move_group) { /* * See perf_event_ctx_lock() for comments on the details * of swizzling perf_event::ctx. */ - mutex_lock_double(&gctx->mutex, &ctx->mutex); - perf_remove_from_context(group_leader, false); list_for_each_entry(sibling, &group_leader->sibling_list, @@ -8311,13 +8477,7 @@ SYSCALL_DEFINE5(perf_event_open, perf_remove_from_context(sibling, false); put_ctx(gctx); } - } else { - mutex_lock(&ctx->mutex); - } - WARN_ON_ONCE(ctx->parent_ctx); - - if (move_group) { /* * Wait for everybody to stop referencing the events through * the old lists, before installing it on new lists. @@ -8349,22 +8509,29 @@ SYSCALL_DEFINE5(perf_event_open, perf_event__state_init(group_leader); perf_install_in_context(ctx, group_leader, group_leader->cpu); get_ctx(ctx); - } - if (!exclusive_event_installable(event, ctx)) { - err = -EBUSY; - mutex_unlock(&ctx->mutex); - fput(event_file); - goto err_context; + /* + * Now that all events are installed in @ctx, nothing + * references @gctx anymore, so drop the last reference we have + * on it. + */ + put_ctx(gctx); } + /* + * Precalculate sample_data sizes; do while holding ctx::mutex such + * that we're serialized against further additions and before + * perf_install_in_context() which is the point the event is active and + * can use these values. + */ + perf_event__header_size(event); + perf_event__id_header_size(event); + perf_install_in_context(ctx, event, event->cpu); perf_unpin_context(ctx); - if (move_group) { + if (move_group) mutex_unlock(&gctx->mutex); - put_ctx(gctx); - } mutex_unlock(&ctx->mutex); put_online_cpus(); @@ -8376,12 +8543,6 @@ SYSCALL_DEFINE5(perf_event_open, mutex_unlock(¤t->perf_event_mutex); /* - * Precalculate sample_data sizes - */ - perf_event__header_size(event); - perf_event__id_header_size(event); - - /* * Drop the reference on the group_event after placing the * new event on the sibling_list. This ensures destruction * of the group leader will find the pointer to itself in @@ -8391,6 +8552,12 @@ SYSCALL_DEFINE5(perf_event_open, fd_install(event_fd, event_file); return event_fd; +err_locked: + if (move_group) + mutex_unlock(&gctx->mutex); + mutex_unlock(&ctx->mutex); +/* err_file: */ + fput(event_file); err_context: perf_unpin_context(ctx); put_ctx(ctx); @@ -9293,25 +9460,9 @@ static void perf_cgroup_attach(struct cgroup_subsys_state *css, task_function_call(task, __perf_cgroup_move, task); } -static void perf_cgroup_exit(struct cgroup_subsys_state *css, - struct cgroup_subsys_state *old_css, - struct task_struct *task) -{ - /* - * cgroup_exit() is called in the copy_process() failure path. - * Ignore this case since the task hasn't ran yet, this avoids - * trying to poke a half freed task state from generic code. - */ - if (!(task->flags & PF_EXITING)) - return; - - task_function_call(task, __perf_cgroup_move, task); -} - struct cgroup_subsys perf_event_cgrp_subsys = { .css_alloc = perf_cgroup_css_alloc, .css_free = perf_cgroup_css_free, - .exit = perf_cgroup_exit, .attach = perf_cgroup_attach, }; #endif /* CONFIG_CGROUP_PERF */ diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c index 182bc30899d5..b5d1ea79c595 100644 --- a/kernel/events/ring_buffer.c +++ b/kernel/events/ring_buffer.c @@ -141,7 +141,7 @@ int perf_output_begin(struct perf_output_handle *handle, perf_output_get_handle(handle); do { - tail = READ_ONCE_CTRL(rb->user_page->data_tail); + tail = READ_ONCE(rb->user_page->data_tail); offset = head = local_read(&rb->head); if (!rb->overwrite && unlikely(CIRC_SPACE(head, tail, perf_data_size(rb)) < size)) diff --git a/kernel/exit.c b/kernel/exit.c index ea95ee1b5ef7..07110c6020a0 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -706,10 +706,12 @@ void do_exit(long code) smp_mb(); raw_spin_unlock_wait(&tsk->pi_lock); - if (unlikely(in_atomic())) + if (unlikely(in_atomic())) { pr_info("note: %s[%d] exited with preempt_count %d\n", current->comm, task_pid_nr(current), preempt_count()); + preempt_count_set(PREEMPT_ENABLED); + } /* sync mm's RSS info before statistics gathering */ if (tsk->mm) @@ -761,7 +763,9 @@ void do_exit(long code) */ flush_ptrace_hw_breakpoint(tsk); + TASKS_RCU(preempt_disable()); TASKS_RCU(tasks_rcu_i = __srcu_read_lock(&tasks_rcu_exit_srcu)); + TASKS_RCU(preempt_enable()); exit_notify(tsk, group_dead); proc_exit_connector(tsk); #ifdef CONFIG_NUMA diff --git a/kernel/fork.c b/kernel/fork.c index 2845623fb582..f97f2c449f5c 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -251,6 +251,7 @@ void __put_task_struct(struct task_struct *tsk) WARN_ON(atomic_read(&tsk->usage)); WARN_ON(tsk == current); + cgroup_free(tsk); task_numa_free(tsk); security_task_free(tsk); exit_creds(tsk); @@ -454,7 +455,8 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) tmp->vm_mm = mm; if (anon_vma_fork(tmp, mpnt)) goto fail_nomem_anon_vma_fork; - tmp->vm_flags &= ~(VM_LOCKED|VM_UFFD_MISSING|VM_UFFD_WP); + tmp->vm_flags &= + ~(VM_LOCKED|VM_LOCKONFAULT|VM_UFFD_MISSING|VM_UFFD_WP); tmp->vm_next = tmp->vm_prev = NULL; tmp->vm_userfaultfd_ctx = NULL_VM_UFFD_CTX; file = tmp->vm_file; @@ -1101,7 +1103,7 @@ static void posix_cpu_timers_init_group(struct signal_struct *sig) cpu_limit = READ_ONCE(sig->rlim[RLIMIT_CPU].rlim_cur); if (cpu_limit != RLIM_INFINITY) { sig->cputime_expires.prof_exp = secs_to_cputime(cpu_limit); - sig->cputimer.running = 1; + sig->cputimer.running = true; } /* The timer lists. */ @@ -1149,10 +1151,6 @@ static int copy_signal(unsigned long clone_flags, struct task_struct *tsk) tty_audit_fork(sig); sched_autogroup_fork(sig); -#ifdef CONFIG_CGROUPS - init_rwsem(&sig->group_rwsem); -#endif - sig->oom_score_adj = current->signal->oom_score_adj; sig->oom_score_adj_min = current->signal->oom_score_adj_min; diff --git a/kernel/futex.c b/kernel/futex.c index 6e443efc65f4..684d7549825a 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -255,9 +255,18 @@ struct futex_hash_bucket { struct plist_head chain; } ____cacheline_aligned_in_smp; -static unsigned long __read_mostly futex_hashsize; +/* + * The base of the bucket array and its size are always used together + * (after initialization only in hash_futex()), so ensure that they + * reside in the same cacheline. + */ +static struct { + struct futex_hash_bucket *queues; + unsigned long hashsize; +} __futex_data __read_mostly __aligned(2*sizeof(long)); +#define futex_queues (__futex_data.queues) +#define futex_hashsize (__futex_data.hashsize) -static struct futex_hash_bucket *futex_queues; /* * Fault injections for futexes. @@ -267,10 +276,10 @@ static struct futex_hash_bucket *futex_queues; static struct { struct fault_attr attr; - u32 ignore_private; + bool ignore_private; } fail_futex = { .attr = FAULT_ATTR_INITIALIZER, - .ignore_private = 0, + .ignore_private = false, }; static int __init setup_fail_futex(char *str) diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig index 9a76e3beda54..3b48dab80164 100644 --- a/kernel/irq/Kconfig +++ b/kernel/irq/Kconfig @@ -30,6 +30,10 @@ config GENERIC_IRQ_LEGACY_ALLOC_HWIRQ config GENERIC_PENDING_IRQ bool +# Support for generic irq migrating off cpu before the cpu is offline. +config GENERIC_IRQ_MIGRATION + bool + # Alpha specific irq affinity mechanism config AUTO_IRQ_AFFINITY bool diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile index d12123526e2b..2fc9cbdf35b6 100644 --- a/kernel/irq/Makefile +++ b/kernel/irq/Makefile @@ -5,5 +5,6 @@ obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o obj-$(CONFIG_IRQ_DOMAIN) += irqdomain.o obj-$(CONFIG_PROC_FS) += proc.o obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o +obj-$(CONFIG_GENERIC_IRQ_MIGRATION) += cpuhotplug.o obj-$(CONFIG_PM_SLEEP) += pm.o obj-$(CONFIG_GENERIC_MSI_IRQ) += msi.o diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c index e28169dd1c36..15206453b12a 100644 --- a/kernel/irq/chip.c +++ b/kernel/irq/chip.c @@ -21,6 +21,20 @@ #include "internals.h" +static irqreturn_t bad_chained_irq(int irq, void *dev_id) +{ + WARN_ONCE(1, "Chained irq %d should not call an action\n", irq); + return IRQ_NONE; +} + +/* + * Chained handlers should never call action on their IRQ. This default + * action will emit warning if such thing happens. + */ +struct irqaction chained_action = { + .handler = bad_chained_irq, +}; + /** * irq_set_chip - set the irq chip for an irq * @irq: irq number @@ -227,6 +241,13 @@ void irq_enable(struct irq_desc *desc) * disabled. If an interrupt happens, then the interrupt flow * handler masks the line at the hardware level and marks it * pending. + * + * If the interrupt chip does not implement the irq_disable callback, + * a driver can disable the lazy approach for a particular irq line by + * calling 'irq_set_status_flags(irq, IRQ_DISABLE_UNLAZY)'. This can + * be used for devices which cannot disable the interrupt at the + * device level under certain circumstances and have to use + * disable_irq[_nosync] instead. */ void irq_disable(struct irq_desc *desc) { @@ -234,6 +255,8 @@ void irq_disable(struct irq_desc *desc) if (desc->irq_data.chip->irq_disable) { desc->irq_data.chip->irq_disable(&desc->irq_data); irq_state_set_masked(desc); + } else if (irq_settings_disable_unlazy(desc)) { + mask_irq(desc); } } @@ -669,7 +692,7 @@ void handle_percpu_irq(struct irq_desc *desc) if (chip->irq_ack) chip->irq_ack(&desc->irq_data); - handle_irq_event_percpu(desc, desc->action); + handle_irq_event_percpu(desc); if (chip->irq_eoi) chip->irq_eoi(&desc->irq_data); @@ -746,6 +769,8 @@ __irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle, if (desc->irq_data.chip != &no_irq_chip) mask_ack_irq(desc); irq_state_set_disabled(desc); + if (is_chained) + desc->action = NULL; desc->depth = 1; } desc->handle_irq = handle; @@ -755,6 +780,7 @@ __irq_do_set_handler(struct irq_desc *desc, irq_flow_handler_t handle, irq_settings_set_noprobe(desc); irq_settings_set_norequest(desc); irq_settings_set_nothread(desc); + desc->action = &chained_action; irq_startup(desc, true); } } diff --git a/kernel/irq/cpuhotplug.c b/kernel/irq/cpuhotplug.c new file mode 100644 index 000000000000..011f8c4c63da --- /dev/null +++ b/kernel/irq/cpuhotplug.c @@ -0,0 +1,82 @@ +/* + * Generic cpu hotunplug interrupt migration code copied from the + * arch/arm implementation + * + * Copyright (C) Russell King + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/interrupt.h> +#include <linux/ratelimit.h> +#include <linux/irq.h> + +#include "internals.h" + +static bool migrate_one_irq(struct irq_desc *desc) +{ + struct irq_data *d = irq_desc_get_irq_data(desc); + const struct cpumask *affinity = d->common->affinity; + struct irq_chip *c; + bool ret = false; + + /* + * If this is a per-CPU interrupt, or the affinity does not + * include this CPU, then we have nothing to do. + */ + if (irqd_is_per_cpu(d) || + !cpumask_test_cpu(smp_processor_id(), affinity)) + return false; + + if (cpumask_any_and(affinity, cpu_online_mask) >= nr_cpu_ids) { + affinity = cpu_online_mask; + ret = true; + } + + c = irq_data_get_irq_chip(d); + if (!c->irq_set_affinity) { + pr_debug("IRQ%u: unable to set affinity\n", d->irq); + } else { + int r = irq_do_set_affinity(d, affinity, false); + if (r) + pr_warn_ratelimited("IRQ%u: set affinity failed(%d).\n", + d->irq, r); + } + + return ret; +} + +/** + * irq_migrate_all_off_this_cpu - Migrate irqs away from offline cpu + * + * The current CPU has been marked offline. Migrate IRQs off this CPU. + * If the affinity settings do not allow other CPUs, force them onto any + * available CPU. + * + * Note: we must iterate over all IRQs, whether they have an attached + * action structure or not, as we need to get chained interrupts too. + */ +void irq_migrate_all_off_this_cpu(void) +{ + unsigned int irq; + struct irq_desc *desc; + unsigned long flags; + + local_irq_save(flags); + + for_each_active_irq(irq) { + bool affinity_broken; + + desc = irq_to_desc(irq); + raw_spin_lock(&desc->lock); + affinity_broken = migrate_one_irq(desc); + raw_spin_unlock(&desc->lock); + + if (affinity_broken) + pr_warn_ratelimited("IRQ%u no longer affine to CPU%u\n", + irq, smp_processor_id()); + } + + local_irq_restore(flags); +} diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c index de41a68fc038..a302cf9a2126 100644 --- a/kernel/irq/handle.c +++ b/kernel/irq/handle.c @@ -22,7 +22,6 @@ /** * handle_bad_irq - handle spurious and unhandled irqs - * @irq: the interrupt number * @desc: description of the interrupt * * Handles spurious and unhandled IRQ's. It also prints a debugmessage. @@ -35,6 +34,7 @@ void handle_bad_irq(struct irq_desc *desc) kstat_incr_irqs_this_cpu(desc); ack_bad_irq(irq); } +EXPORT_SYMBOL_GPL(handle_bad_irq); /* * Special, empty irq handler: @@ -132,11 +132,11 @@ void __irq_wake_thread(struct irq_desc *desc, struct irqaction *action) wake_up_process(action->thread); } -irqreturn_t -handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action) +irqreturn_t handle_irq_event_percpu(struct irq_desc *desc) { irqreturn_t retval = IRQ_NONE; unsigned int flags = 0, irq = desc->irq_data.irq; + struct irqaction *action = desc->action; do { irqreturn_t res; @@ -184,14 +184,13 @@ handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action) irqreturn_t handle_irq_event(struct irq_desc *desc) { - struct irqaction *action = desc->action; irqreturn_t ret; desc->istate &= ~IRQS_PENDING; irqd_set(&desc->irq_data, IRQD_IRQ_INPROGRESS); raw_spin_unlock(&desc->lock); - ret = handle_irq_event_percpu(desc, action); + ret = handle_irq_event_percpu(desc); raw_spin_lock(&desc->lock); irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS); diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h index 5ef0c2dbe930..05c2188271b8 100644 --- a/kernel/irq/internals.h +++ b/kernel/irq/internals.h @@ -18,6 +18,8 @@ extern bool noirqdebug; +extern struct irqaction chained_action; + /* * Bits used by threaded handlers: * IRQTF_RUNTHREAD - signals that the interrupt handler thread should run @@ -81,7 +83,7 @@ extern void irq_mark_irq(unsigned int irq); extern void init_kstat_irqs(struct irq_desc *desc, int node, int nr); -irqreturn_t handle_irq_event_percpu(struct irq_desc *desc, struct irqaction *action); +irqreturn_t handle_irq_event_percpu(struct irq_desc *desc); irqreturn_t handle_irq_event(struct irq_desc *desc); /* Resending of interrupts :*/ diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index dc9d27c0c158..22aa9612ef7c 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -27,6 +27,57 @@ static int irq_domain_alloc_descs(int virq, unsigned int nr_irqs, irq_hw_number_t hwirq, int node); static void irq_domain_check_hierarchy(struct irq_domain *domain); +struct irqchip_fwid { + struct fwnode_handle fwnode; + char *name; + void *data; +}; + +/** + * irq_domain_alloc_fwnode - Allocate a fwnode_handle suitable for + * identifying an irq domain + * @data: optional user-provided data + * + * Allocate a struct device_node, and return a poiner to the embedded + * fwnode_handle (or NULL on failure). + */ +struct fwnode_handle *irq_domain_alloc_fwnode(void *data) +{ + struct irqchip_fwid *fwid; + char *name; + + fwid = kzalloc(sizeof(*fwid), GFP_KERNEL); + name = kasprintf(GFP_KERNEL, "irqchip@%p", data); + + if (!fwid || !name) { + kfree(fwid); + kfree(name); + return NULL; + } + + fwid->name = name; + fwid->data = data; + fwid->fwnode.type = FWNODE_IRQCHIP; + return &fwid->fwnode; +} + +/** + * irq_domain_free_fwnode - Free a non-OF-backed fwnode_handle + * + * Free a fwnode_handle allocated with irq_domain_alloc_fwnode. + */ +void irq_domain_free_fwnode(struct fwnode_handle *fwnode) +{ + struct irqchip_fwid *fwid; + + if (WARN_ON(fwnode->type != FWNODE_IRQCHIP)) + return; + + fwid = container_of(fwnode, struct irqchip_fwid, fwnode); + kfree(fwid->name); + kfree(fwid); +} + /** * __irq_domain_add() - Allocate a new irq_domain data structure * @of_node: optional device-tree node of the interrupt controller @@ -40,23 +91,28 @@ static void irq_domain_check_hierarchy(struct irq_domain *domain); * Allocates and initialize and irq_domain structure. * Returns pointer to IRQ domain, or NULL on failure. */ -struct irq_domain *__irq_domain_add(struct device_node *of_node, int size, +struct irq_domain *__irq_domain_add(struct fwnode_handle *fwnode, int size, irq_hw_number_t hwirq_max, int direct_max, const struct irq_domain_ops *ops, void *host_data) { struct irq_domain *domain; + struct device_node *of_node; + + of_node = to_of_node(fwnode); domain = kzalloc_node(sizeof(*domain) + (sizeof(unsigned int) * size), GFP_KERNEL, of_node_to_nid(of_node)); if (WARN_ON(!domain)) return NULL; + of_node_get(of_node); + /* Fill structure */ INIT_RADIX_TREE(&domain->revmap_tree, GFP_KERNEL); domain->ops = ops; domain->host_data = host_data; - domain->of_node = of_node_get(of_node); + domain->fwnode = fwnode; domain->hwirq_max = hwirq_max; domain->revmap_size = size; domain->revmap_direct_max_irq = direct_max; @@ -102,7 +158,7 @@ void irq_domain_remove(struct irq_domain *domain) pr_debug("Removed domain %s\n", domain->name); - of_node_put(domain->of_node); + of_node_put(irq_domain_get_of_node(domain)); kfree(domain); } EXPORT_SYMBOL_GPL(irq_domain_remove); @@ -133,7 +189,7 @@ struct irq_domain *irq_domain_add_simple(struct device_node *of_node, { struct irq_domain *domain; - domain = __irq_domain_add(of_node, size, size, 0, ops, host_data); + domain = __irq_domain_add(of_node_to_fwnode(of_node), size, size, 0, ops, host_data); if (!domain) return NULL; @@ -177,7 +233,7 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node, { struct irq_domain *domain; - domain = __irq_domain_add(of_node, first_hwirq + size, + domain = __irq_domain_add(of_node_to_fwnode(of_node), first_hwirq + size, first_hwirq + size, 0, ops, host_data); if (domain) irq_domain_associate_many(domain, first_irq, first_hwirq, size); @@ -187,12 +243,12 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node, EXPORT_SYMBOL_GPL(irq_domain_add_legacy); /** - * irq_find_matching_host() - Locates a domain for a given device node - * @node: device-tree node of the interrupt controller + * irq_find_matching_fwnode() - Locates a domain for a given fwnode + * @fwnode: FW descriptor of the interrupt controller * @bus_token: domain-specific data */ -struct irq_domain *irq_find_matching_host(struct device_node *node, - enum irq_domain_bus_token bus_token) +struct irq_domain *irq_find_matching_fwnode(struct fwnode_handle *fwnode, + enum irq_domain_bus_token bus_token) { struct irq_domain *h, *found = NULL; int rc; @@ -209,9 +265,9 @@ struct irq_domain *irq_find_matching_host(struct device_node *node, mutex_lock(&irq_domain_mutex); list_for_each_entry(h, &irq_domain_list, link) { if (h->ops->match) - rc = h->ops->match(h, node, bus_token); + rc = h->ops->match(h, to_of_node(fwnode), bus_token); else - rc = ((h->of_node != NULL) && (h->of_node == node) && + rc = ((fwnode != NULL) && (h->fwnode == fwnode) && ((bus_token == DOMAIN_BUS_ANY) || (h->bus_token == bus_token))); @@ -223,7 +279,7 @@ struct irq_domain *irq_find_matching_host(struct device_node *node, mutex_unlock(&irq_domain_mutex); return found; } -EXPORT_SYMBOL_GPL(irq_find_matching_host); +EXPORT_SYMBOL_GPL(irq_find_matching_fwnode); /** * irq_set_default_host() - Set a "default" irq domain @@ -336,10 +392,12 @@ EXPORT_SYMBOL_GPL(irq_domain_associate); void irq_domain_associate_many(struct irq_domain *domain, unsigned int irq_base, irq_hw_number_t hwirq_base, int count) { + struct device_node *of_node; int i; + of_node = irq_domain_get_of_node(domain); pr_debug("%s(%s, irqbase=%i, hwbase=%i, count=%i)\n", __func__, - of_node_full_name(domain->of_node), irq_base, (int)hwirq_base, count); + of_node_full_name(of_node), irq_base, (int)hwirq_base, count); for (i = 0; i < count; i++) { irq_domain_associate(domain, irq_base + i, hwirq_base + i); @@ -359,12 +417,14 @@ EXPORT_SYMBOL_GPL(irq_domain_associate_many); */ unsigned int irq_create_direct_mapping(struct irq_domain *domain) { + struct device_node *of_node; unsigned int virq; if (domain == NULL) domain = irq_default_domain; - virq = irq_alloc_desc_from(1, of_node_to_nid(domain->of_node)); + of_node = irq_domain_get_of_node(domain); + virq = irq_alloc_desc_from(1, of_node_to_nid(of_node)); if (!virq) { pr_debug("create_direct virq allocation failed\n"); return 0; @@ -399,6 +459,7 @@ EXPORT_SYMBOL_GPL(irq_create_direct_mapping); unsigned int irq_create_mapping(struct irq_domain *domain, irq_hw_number_t hwirq) { + struct device_node *of_node; int virq; pr_debug("irq_create_mapping(0x%p, 0x%lx)\n", domain, hwirq); @@ -412,6 +473,8 @@ unsigned int irq_create_mapping(struct irq_domain *domain, } pr_debug("-> using domain @%p\n", domain); + of_node = irq_domain_get_of_node(domain); + /* Check if mapping already exists */ virq = irq_find_mapping(domain, hwirq); if (virq) { @@ -420,8 +483,7 @@ unsigned int irq_create_mapping(struct irq_domain *domain, } /* Allocate a virtual interrupt number */ - virq = irq_domain_alloc_descs(-1, 1, hwirq, - of_node_to_nid(domain->of_node)); + virq = irq_domain_alloc_descs(-1, 1, hwirq, of_node_to_nid(of_node)); if (virq <= 0) { pr_debug("-> virq allocation failed\n"); return 0; @@ -433,7 +495,7 @@ unsigned int irq_create_mapping(struct irq_domain *domain, } pr_debug("irq %lu on domain %s mapped to virtual irq %u\n", - hwirq, of_node_full_name(domain->of_node), virq); + hwirq, of_node_full_name(of_node), virq); return virq; } @@ -460,10 +522,12 @@ EXPORT_SYMBOL_GPL(irq_create_mapping); int irq_create_strict_mappings(struct irq_domain *domain, unsigned int irq_base, irq_hw_number_t hwirq_base, int count) { + struct device_node *of_node; int ret; + of_node = irq_domain_get_of_node(domain); ret = irq_alloc_descs(irq_base, irq_base, count, - of_node_to_nid(domain->of_node)); + of_node_to_nid(of_node)); if (unlikely(ret < 0)) return ret; @@ -472,28 +536,56 @@ int irq_create_strict_mappings(struct irq_domain *domain, unsigned int irq_base, } EXPORT_SYMBOL_GPL(irq_create_strict_mappings); -unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) +static int irq_domain_translate(struct irq_domain *d, + struct irq_fwspec *fwspec, + irq_hw_number_t *hwirq, unsigned int *type) +{ +#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY + if (d->ops->translate) + return d->ops->translate(d, fwspec, hwirq, type); +#endif + if (d->ops->xlate) + return d->ops->xlate(d, to_of_node(fwspec->fwnode), + fwspec->param, fwspec->param_count, + hwirq, type); + + /* If domain has no translation, then we assume interrupt line */ + *hwirq = fwspec->param[0]; + return 0; +} + +static void of_phandle_args_to_fwspec(struct of_phandle_args *irq_data, + struct irq_fwspec *fwspec) +{ + int i; + + fwspec->fwnode = irq_data->np ? &irq_data->np->fwnode : NULL; + fwspec->param_count = irq_data->args_count; + + for (i = 0; i < irq_data->args_count; i++) + fwspec->param[i] = irq_data->args[i]; +} + +unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec) { struct irq_domain *domain; irq_hw_number_t hwirq; unsigned int type = IRQ_TYPE_NONE; int virq; - domain = irq_data->np ? irq_find_host(irq_data->np) : irq_default_domain; + if (fwspec->fwnode) + domain = irq_find_matching_fwnode(fwspec->fwnode, DOMAIN_BUS_ANY); + else + domain = irq_default_domain; + if (!domain) { pr_warn("no irq domain found for %s !\n", - of_node_full_name(irq_data->np)); + of_node_full_name(to_of_node(fwspec->fwnode))); return 0; } - /* If domain has no translation, then we assume interrupt line */ - if (domain->ops->xlate == NULL) - hwirq = irq_data->args[0]; - else { - if (domain->ops->xlate(domain, irq_data->np, irq_data->args, - irq_data->args_count, &hwirq, &type)) - return 0; - } + if (irq_domain_translate(domain, fwspec, &hwirq, &type)) + return 0; if (irq_domain_is_hierarchy(domain)) { /* @@ -504,7 +596,7 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) if (virq) return virq; - virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, irq_data); + virq = irq_domain_alloc_irqs(domain, 1, NUMA_NO_NODE, fwspec); if (virq <= 0) return 0; } else { @@ -520,6 +612,15 @@ unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) irq_set_irq_type(virq, type); return virq; } +EXPORT_SYMBOL_GPL(irq_create_fwspec_mapping); + +unsigned int irq_create_of_mapping(struct of_phandle_args *irq_data) +{ + struct irq_fwspec fwspec; + + of_phandle_args_to_fwspec(irq_data, &fwspec); + return irq_create_fwspec_mapping(&fwspec); +} EXPORT_SYMBOL_GPL(irq_create_of_mapping); /** @@ -590,14 +691,16 @@ static int virq_debug_show(struct seq_file *m, void *private) "name", "mapped", "linear-max", "direct-max", "devtree-node"); mutex_lock(&irq_domain_mutex); list_for_each_entry(domain, &irq_domain_list, link) { + struct device_node *of_node; int count = 0; + of_node = irq_domain_get_of_node(domain); radix_tree_for_each_slot(slot, &domain->revmap_tree, &iter, 0) count++; seq_printf(m, "%c%-16s %6u %10u %10u %s\n", domain == irq_default_domain ? '*' : ' ', domain->name, domain->revmap_size + count, domain->revmap_size, domain->revmap_direct_max_irq, - domain->of_node ? of_node_full_name(domain->of_node) : ""); + of_node ? of_node_full_name(of_node) : ""); } mutex_unlock(&irq_domain_mutex); @@ -751,11 +854,11 @@ static int irq_domain_alloc_descs(int virq, unsigned int cnt, #ifdef CONFIG_IRQ_DOMAIN_HIERARCHY /** - * irq_domain_add_hierarchy - Add a irqdomain into the hierarchy + * irq_domain_create_hierarchy - Add a irqdomain into the hierarchy * @parent: Parent irq domain to associate with the new domain * @flags: Irq domain flags associated to the domain * @size: Size of the domain. See below - * @node: Optional device-tree node of the interrupt controller + * @fwnode: Optional fwnode of the interrupt controller * @ops: Pointer to the interrupt domain callbacks * @host_data: Controller private data pointer * @@ -765,19 +868,19 @@ static int irq_domain_alloc_descs(int virq, unsigned int cnt, * domain flags are set. * Returns pointer to IRQ domain, or NULL on failure. */ -struct irq_domain *irq_domain_add_hierarchy(struct irq_domain *parent, +struct irq_domain *irq_domain_create_hierarchy(struct irq_domain *parent, unsigned int flags, unsigned int size, - struct device_node *node, + struct fwnode_handle *fwnode, const struct irq_domain_ops *ops, void *host_data) { struct irq_domain *domain; if (size) - domain = irq_domain_add_linear(node, size, ops, host_data); + domain = irq_domain_create_linear(fwnode, size, ops, host_data); else - domain = irq_domain_add_tree(node, ops, host_data); + domain = irq_domain_create_tree(fwnode, ops, host_data); if (domain) { domain->parent = parent; domain->flags |= flags; diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index f9a59f6cabd2..0eebaeef317b 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -258,37 +258,6 @@ int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m) } EXPORT_SYMBOL_GPL(irq_set_affinity_hint); -/** - * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt - * @irq: interrupt number to set affinity - * @vcpu_info: vCPU specific data - * - * This function uses the vCPU specific data to set the vCPU - * affinity for an irq. The vCPU specific data is passed from - * outside, such as KVM. One example code path is as below: - * KVM -> IOMMU -> irq_set_vcpu_affinity(). - */ -int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info) -{ - unsigned long flags; - struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); - struct irq_data *data; - struct irq_chip *chip; - int ret = -ENOSYS; - - if (!desc) - return -EINVAL; - - data = irq_desc_get_irq_data(desc); - chip = irq_data_get_irq_chip(data); - if (chip && chip->irq_set_vcpu_affinity) - ret = chip->irq_set_vcpu_affinity(data, vcpu_info); - irq_put_desc_unlock(desc, flags); - - return ret; -} -EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity); - static void irq_affinity_notify(struct work_struct *work) { struct irq_affinity_notify *notify = @@ -424,6 +393,37 @@ setup_affinity(struct irq_desc *desc, struct cpumask *mask) } #endif +/** + * irq_set_vcpu_affinity - Set vcpu affinity for the interrupt + * @irq: interrupt number to set affinity + * @vcpu_info: vCPU specific data + * + * This function uses the vCPU specific data to set the vCPU + * affinity for an irq. The vCPU specific data is passed from + * outside, such as KVM. One example code path is as below: + * KVM -> IOMMU -> irq_set_vcpu_affinity(). + */ +int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info) +{ + unsigned long flags; + struct irq_desc *desc = irq_get_desc_lock(irq, &flags, 0); + struct irq_data *data; + struct irq_chip *chip; + int ret = -ENOSYS; + + if (!desc) + return -EINVAL; + + data = irq_desc_get_irq_data(desc); + chip = irq_data_get_irq_chip(data); + if (chip && chip->irq_set_vcpu_affinity) + ret = chip->irq_set_vcpu_affinity(data, vcpu_info); + irq_put_desc_unlock(desc, flags); + + return ret; +} +EXPORT_SYMBOL_GPL(irq_set_vcpu_affinity); + void __disable_irq(struct irq_desc *desc) { if (!desc->depth++) @@ -730,6 +730,12 @@ static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id) return IRQ_NONE; } +static irqreturn_t irq_forced_secondary_handler(int irq, void *dev_id) +{ + WARN(1, "Secondary action handler called for irq %d\n", irq); + return IRQ_NONE; +} + static int irq_wait_for_interrupt(struct irqaction *action) { set_current_state(TASK_INTERRUPTIBLE); @@ -756,7 +762,8 @@ static int irq_wait_for_interrupt(struct irqaction *action) static void irq_finalize_oneshot(struct irq_desc *desc, struct irqaction *action) { - if (!(desc->istate & IRQS_ONESHOT)) + if (!(desc->istate & IRQS_ONESHOT) || + action->handler == irq_forced_secondary_handler) return; again: chip_bus_lock(desc); @@ -910,6 +917,18 @@ static void irq_thread_dtor(struct callback_head *unused) irq_finalize_oneshot(desc, action); } +static void irq_wake_secondary(struct irq_desc *desc, struct irqaction *action) +{ + struct irqaction *secondary = action->secondary; + + if (WARN_ON_ONCE(!secondary)) + return; + + raw_spin_lock_irq(&desc->lock); + __irq_wake_thread(desc, secondary); + raw_spin_unlock_irq(&desc->lock); +} + /* * Interrupt handler thread */ @@ -940,6 +959,8 @@ static int irq_thread(void *data) action_ret = handler_fn(desc, action); if (action_ret == IRQ_HANDLED) atomic_inc(&desc->threads_handled); + if (action_ret == IRQ_WAKE_THREAD) + irq_wake_secondary(desc, action); wake_threads_waitq(desc); } @@ -984,20 +1005,36 @@ void irq_wake_thread(unsigned int irq, void *dev_id) } EXPORT_SYMBOL_GPL(irq_wake_thread); -static void irq_setup_forced_threading(struct irqaction *new) +static int irq_setup_forced_threading(struct irqaction *new) { if (!force_irqthreads) - return; + return 0; if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT)) - return; + return 0; new->flags |= IRQF_ONESHOT; - if (!new->thread_fn) { - set_bit(IRQTF_FORCED_THREAD, &new->thread_flags); - new->thread_fn = new->handler; - new->handler = irq_default_primary_handler; + /* + * Handle the case where we have a real primary handler and a + * thread handler. We force thread them as well by creating a + * secondary action. + */ + if (new->handler != irq_default_primary_handler && new->thread_fn) { + /* Allocate the secondary action */ + new->secondary = kzalloc(sizeof(struct irqaction), GFP_KERNEL); + if (!new->secondary) + return -ENOMEM; + new->secondary->handler = irq_forced_secondary_handler; + new->secondary->thread_fn = new->thread_fn; + new->secondary->dev_id = new->dev_id; + new->secondary->irq = new->irq; + new->secondary->name = new->name; } + /* Deal with the primary handler */ + set_bit(IRQTF_FORCED_THREAD, &new->thread_flags); + new->thread_fn = new->handler; + new->handler = irq_default_primary_handler; + return 0; } static int irq_request_resources(struct irq_desc *desc) @@ -1017,6 +1054,48 @@ static void irq_release_resources(struct irq_desc *desc) c->irq_release_resources(d); } +static int +setup_irq_thread(struct irqaction *new, unsigned int irq, bool secondary) +{ + struct task_struct *t; + struct sched_param param = { + .sched_priority = MAX_USER_RT_PRIO/2, + }; + + if (!secondary) { + t = kthread_create(irq_thread, new, "irq/%d-%s", irq, + new->name); + } else { + t = kthread_create(irq_thread, new, "irq/%d-s-%s", irq, + new->name); + param.sched_priority -= 1; + } + + if (IS_ERR(t)) + return PTR_ERR(t); + + sched_setscheduler_nocheck(t, SCHED_FIFO, ¶m); + + /* + * We keep the reference to the task struct even if + * the thread dies to avoid that the interrupt code + * references an already freed task_struct. + */ + get_task_struct(t); + new->thread = t; + /* + * Tell the thread to set its affinity. This is + * important for shared interrupt handlers as we do + * not invoke setup_affinity() for the secondary + * handlers as everything is already set up. Even for + * interrupts marked with IRQF_NO_BALANCE this is + * correct as we want the thread to move to the cpu(s) + * on which the requesting code placed the interrupt. + */ + set_bit(IRQTF_AFFINITY, &new->thread_flags); + return 0; +} + /* * Internal function to register an irqaction - typically used to * allocate special interrupts that are part of the architecture. @@ -1037,6 +1116,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) if (!try_module_get(desc->owner)) return -ENODEV; + new->irq = irq; + /* * Check whether the interrupt nests into another interrupt * thread. @@ -1054,8 +1135,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) */ new->handler = irq_nested_primary_handler; } else { - if (irq_settings_can_thread(desc)) - irq_setup_forced_threading(new); + if (irq_settings_can_thread(desc)) { + ret = irq_setup_forced_threading(new); + if (ret) + goto out_mput; + } } /* @@ -1064,37 +1148,14 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) * thread. */ if (new->thread_fn && !nested) { - struct task_struct *t; - static const struct sched_param param = { - .sched_priority = MAX_USER_RT_PRIO/2, - }; - - t = kthread_create(irq_thread, new, "irq/%d-%s", irq, - new->name); - if (IS_ERR(t)) { - ret = PTR_ERR(t); + ret = setup_irq_thread(new, irq, false); + if (ret) goto out_mput; + if (new->secondary) { + ret = setup_irq_thread(new->secondary, irq, true); + if (ret) + goto out_thread; } - - sched_setscheduler_nocheck(t, SCHED_FIFO, ¶m); - - /* - * We keep the reference to the task struct even if - * the thread dies to avoid that the interrupt code - * references an already freed task_struct. - */ - get_task_struct(t); - new->thread = t; - /* - * Tell the thread to set its affinity. This is - * important for shared interrupt handlers as we do - * not invoke setup_affinity() for the secondary - * handlers as everything is already set up. Even for - * interrupts marked with IRQF_NO_BALANCE this is - * correct as we want the thread to move to the cpu(s) - * on which the requesting code placed the interrupt. - */ - set_bit(IRQTF_AFFINITY, &new->thread_flags); } if (!alloc_cpumask_var(&mask, GFP_KERNEL)) { @@ -1267,7 +1328,6 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) irq, nmsk, omsk); } - new->irq = irq; *old_ptr = new; irq_pm_install_action(desc, new); @@ -1293,6 +1353,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new) */ if (new->thread) wake_up_process(new->thread); + if (new->secondary) + wake_up_process(new->secondary->thread); register_irq_proc(irq, desc); new->dir = NULL; @@ -1323,6 +1385,13 @@ out_thread: kthread_stop(t); put_task_struct(t); } + if (new->secondary && new->secondary->thread) { + struct task_struct *t = new->secondary->thread; + + new->secondary->thread = NULL; + kthread_stop(t); + put_task_struct(t); + } out_mput: module_put(desc->owner); return ret; @@ -1394,6 +1463,7 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id) /* If this was the last handler, shut down the IRQ line: */ if (!desc->action) { + irq_settings_clr_disable_unlazy(desc); irq_shutdown(desc); irq_release_resources(desc); } @@ -1430,9 +1500,14 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id) if (action->thread) { kthread_stop(action->thread); put_task_struct(action->thread); + if (action->secondary && action->secondary->thread) { + kthread_stop(action->secondary->thread); + put_task_struct(action->secondary->thread); + } } module_put(desc->owner); + kfree(action->secondary); return action; } @@ -1576,8 +1651,10 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler, retval = __setup_irq(irq, desc, action); chip_bus_sync_unlock(desc); - if (retval) + if (retval) { + kfree(action->secondary); kfree(action); + } #ifdef CONFIG_DEBUG_SHIRQ_FIXME if (!retval && (irqflags & IRQF_SHARED)) { @@ -1761,6 +1838,7 @@ void free_percpu_irq(unsigned int irq, void __percpu *dev_id) kfree(__free_percpu_irq(irq, dev_id)); chip_bus_sync_unlock(desc); } +EXPORT_SYMBOL_GPL(free_percpu_irq); /** * setup_percpu_irq - setup a per-cpu interrupt @@ -1790,9 +1868,10 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act) * @devname: An ascii name for the claiming device * @dev_id: A percpu cookie passed back to the handler function * - * This call allocates interrupt resources, but doesn't - * automatically enable the interrupt. It has to be done on each - * CPU using enable_percpu_irq(). + * This call allocates interrupt resources and enables the + * interrupt on the local CPU. If the interrupt is supposed to be + * enabled on other CPUs, it has to be done on each CPU using + * enable_percpu_irq(). * * Dev_id must be globally unique. It is a per-cpu variable, and * the handler gets called with the interrupted CPU's instance of @@ -1831,6 +1910,7 @@ int request_percpu_irq(unsigned int irq, irq_handler_t handler, return retval; } +EXPORT_SYMBOL_GPL(request_percpu_irq); /** * irq_get_irqchip_state - returns the irqchip state of a interrupt. diff --git a/kernel/irq/msi.c b/kernel/irq/msi.c index 7e6512b9dc1f..6b0c0b74a2a1 100644 --- a/kernel/irq/msi.c +++ b/kernel/irq/msi.c @@ -228,22 +228,18 @@ static void msi_domain_update_chip_ops(struct msi_domain_info *info) { struct irq_chip *chip = info->chip; - BUG_ON(!chip); - if (!chip->irq_mask) - chip->irq_mask = pci_msi_mask_irq; - if (!chip->irq_unmask) - chip->irq_unmask = pci_msi_unmask_irq; + BUG_ON(!chip || !chip->irq_mask || !chip->irq_unmask); if (!chip->irq_set_affinity) chip->irq_set_affinity = msi_domain_set_affinity; } /** * msi_create_irq_domain - Create a MSI interrupt domain - * @of_node: Optional device-tree node of the interrupt controller + * @fwnode: Optional fwnode of the interrupt controller * @info: MSI domain info * @parent: Parent irq domain */ -struct irq_domain *msi_create_irq_domain(struct device_node *node, +struct irq_domain *msi_create_irq_domain(struct fwnode_handle *fwnode, struct msi_domain_info *info, struct irq_domain *parent) { @@ -252,8 +248,8 @@ struct irq_domain *msi_create_irq_domain(struct device_node *node, if (info->flags & MSI_FLAG_USE_DEF_CHIP_OPS) msi_domain_update_chip_ops(info); - return irq_domain_add_hierarchy(parent, 0, 0, node, &msi_domain_ops, - info); + return irq_domain_create_hierarchy(parent, 0, 0, fwnode, + &msi_domain_ops, info); } /** diff --git a/kernel/irq/pm.c b/kernel/irq/pm.c index 21c62617a35a..e80c4400118a 100644 --- a/kernel/irq/pm.c +++ b/kernel/irq/pm.c @@ -21,7 +21,7 @@ bool irq_pm_check_wakeup(struct irq_desc *desc) desc->istate |= IRQS_SUSPENDED | IRQS_PENDING; desc->depth++; irq_disable(desc); - pm_system_wakeup(); + pm_system_irq_wakeup(irq_desc_get_irq(desc)); return true; } return false; diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c index e3a8c9577ba6..a916cf144b65 100644 --- a/kernel/irq/proc.c +++ b/kernel/irq/proc.c @@ -12,6 +12,7 @@ #include <linux/seq_file.h> #include <linux/interrupt.h> #include <linux/kernel_stat.h> +#include <linux/mutex.h> #include "internals.h" @@ -323,18 +324,29 @@ void register_handler_proc(unsigned int irq, struct irqaction *action) void register_irq_proc(unsigned int irq, struct irq_desc *desc) { + static DEFINE_MUTEX(register_lock); char name [MAX_NAMELEN]; - if (!root_irq_dir || (desc->irq_data.chip == &no_irq_chip) || desc->dir) + if (!root_irq_dir || (desc->irq_data.chip == &no_irq_chip)) return; + /* + * irq directories are registered only when a handler is + * added, not when the descriptor is created, so multiple + * tasks might try to register at the same time. + */ + mutex_lock(®ister_lock); + + if (desc->dir) + goto out_unlock; + memset(name, 0, MAX_NAMELEN); sprintf(name, "%d", irq); /* create /proc/irq/1234 */ desc->dir = proc_mkdir(name, root_irq_dir); if (!desc->dir) - return; + goto out_unlock; #ifdef CONFIG_SMP /* create /proc/irq/<irq>/smp_affinity */ @@ -355,6 +367,9 @@ void register_irq_proc(unsigned int irq, struct irq_desc *desc) proc_create_data("spurious", 0444, desc->dir, &irq_spurious_proc_fops, (void *)(long)irq); + +out_unlock: + mutex_unlock(®ister_lock); } void unregister_irq_proc(unsigned int irq, struct irq_desc *desc) @@ -460,7 +475,7 @@ int show_interrupts(struct seq_file *p, void *v) for_each_online_cpu(j) any_count |= kstat_irqs_cpu(i, j); action = desc->action; - if (!action && !any_count) + if ((!action || action == &chained_action) && !any_count) goto out; seq_printf(p, "%*d: ", prec, i); diff --git a/kernel/irq/settings.h b/kernel/irq/settings.h index 3320b84cc60f..320579d89091 100644 --- a/kernel/irq/settings.h +++ b/kernel/irq/settings.h @@ -15,6 +15,7 @@ enum { _IRQ_NESTED_THREAD = IRQ_NESTED_THREAD, _IRQ_PER_CPU_DEVID = IRQ_PER_CPU_DEVID, _IRQ_IS_POLLED = IRQ_IS_POLLED, + _IRQ_DISABLE_UNLAZY = IRQ_DISABLE_UNLAZY, _IRQF_MODIFY_MASK = IRQF_MODIFY_MASK, }; @@ -28,6 +29,7 @@ enum { #define IRQ_NESTED_THREAD GOT_YOU_MORON #define IRQ_PER_CPU_DEVID GOT_YOU_MORON #define IRQ_IS_POLLED GOT_YOU_MORON +#define IRQ_DISABLE_UNLAZY GOT_YOU_MORON #undef IRQF_MODIFY_MASK #define IRQF_MODIFY_MASK GOT_YOU_MORON @@ -154,3 +156,13 @@ static inline bool irq_settings_is_polled(struct irq_desc *desc) { return desc->status_use_accessors & _IRQ_IS_POLLED; } + +static inline bool irq_settings_disable_unlazy(struct irq_desc *desc) +{ + return desc->status_use_accessors & _IRQ_DISABLE_UNLAZY; +} + +static inline void irq_settings_clr_disable_unlazy(struct irq_desc *desc) +{ + desc->status_use_accessors &= ~_IRQ_DISABLE_UNLAZY; +} diff --git a/kernel/kexec.c b/kernel/kexec.c index 4c5edc357923..d873b64fbddc 100644 --- a/kernel/kexec.c +++ b/kernel/kexec.c @@ -6,6 +6,8 @@ * Version 2. See the file COPYING for more details. */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/capability.h> #include <linux/mm.h> #include <linux/file.h> diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c index 201b45327804..11b64a63c0f8 100644 --- a/kernel/kexec_core.c +++ b/kernel/kexec_core.c @@ -6,7 +6,7 @@ * Version 2. See the file COPYING for more details. */ -#define pr_fmt(fmt) "kexec: " fmt +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/capability.h> #include <linux/mm.h> @@ -1027,7 +1027,7 @@ static int __init crash_notes_memory_init(void) crash_notes = __alloc_percpu(size, align); if (!crash_notes) { - pr_warn("Kexec: Memory allocation for saving cpu register states failed\n"); + pr_warn("Memory allocation for saving cpu register states failed\n"); return -ENOMEM; } return 0; @@ -1149,7 +1149,7 @@ static int __init parse_crashkernel_simple(char *cmdline, if (*cur == '@') *crash_base = memparse(cur+1, &cur); else if (*cur != ' ' && *cur != '\0') { - pr_warn("crashkernel: unrecognized char\n"); + pr_warn("crashkernel: unrecognized char: %c\n", *cur); return -EINVAL; } @@ -1186,12 +1186,12 @@ static int __init parse_crashkernel_suffix(char *cmdline, /* check with suffix */ if (strncmp(cur, suffix, strlen(suffix))) { - pr_warn("crashkernel: unrecognized char\n"); + pr_warn("crashkernel: unrecognized char: %c\n", *cur); return -EINVAL; } cur += strlen(suffix); if (*cur != ' ' && *cur != '\0') { - pr_warn("crashkernel: unrecognized char\n"); + pr_warn("crashkernel: unrecognized char: %c\n", *cur); return -EINVAL; } diff --git a/kernel/kexec_file.c b/kernel/kexec_file.c index 6a9a3f2a0e8e..b70ada0028d2 100644 --- a/kernel/kexec_file.c +++ b/kernel/kexec_file.c @@ -9,6 +9,8 @@ * Version 2. See the file COPYING for more details. */ +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + #include <linux/capability.h> #include <linux/mm.h> #include <linux/file.h> diff --git a/kernel/kmod.c b/kernel/kmod.c index da98d0593de2..0277d1216f80 100644 --- a/kernel/kmod.c +++ b/kernel/kmod.c @@ -327,9 +327,13 @@ static void call_usermodehelper_exec_work(struct work_struct *work) call_usermodehelper_exec_sync(sub_info); } else { pid_t pid; - + /* + * Use CLONE_PARENT to reparent it to kthreadd; we do not + * want to pollute current->children, and we need a parent + * that always ignores SIGCHLD to ensure auto-reaping. + */ pid = kernel_thread(call_usermodehelper_exec_async, sub_info, - SIGCHLD); + CLONE_PARENT | SIGCHLD); if (pid < 0) { sub_info->retval = pid; umh_complete(sub_info); diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 8acfbf773e06..deae3907ac1e 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -2738,7 +2738,7 @@ static void __lockdep_trace_alloc(gfp_t gfp_mask, unsigned long flags) return; /* no reclaim without waiting on it */ - if (!(gfp_mask & __GFP_WAIT)) + if (!(gfp_mask & __GFP_DIRECT_RECLAIM)) return; /* this guy won't enter reclaim */ @@ -3068,7 +3068,7 @@ static int __lock_is_held(struct lockdep_map *lock); static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, int trylock, int read, int check, int hardirqs_off, struct lockdep_map *nest_lock, unsigned long ip, - int references) + int references, int pin_count) { struct task_struct *curr = current; struct lock_class *class = NULL; @@ -3157,7 +3157,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, hlock->waittime_stamp = 0; hlock->holdtime_stamp = lockstat_clock(); #endif - hlock->pin_count = 0; + hlock->pin_count = pin_count; if (check && !mark_irqflags(curr, hlock)) return 0; @@ -3343,7 +3343,7 @@ found_it: hlock_class(hlock)->subclass, hlock->trylock, hlock->read, hlock->check, hlock->hardirqs_off, hlock->nest_lock, hlock->acquire_ip, - hlock->references)) + hlock->references, hlock->pin_count)) return 0; } @@ -3433,7 +3433,7 @@ found_it: hlock_class(hlock)->subclass, hlock->trylock, hlock->read, hlock->check, hlock->hardirqs_off, hlock->nest_lock, hlock->acquire_ip, - hlock->references)) + hlock->references, hlock->pin_count)) return 0; } @@ -3583,7 +3583,7 @@ void lock_acquire(struct lockdep_map *lock, unsigned int subclass, current->lockdep_recursion = 1; trace_lock_acquire(lock, subclass, trylock, read, check, nest_lock, ip); __lock_acquire(lock, subclass, trylock, read, check, - irqs_disabled_flags(flags), nest_lock, ip, 0); + irqs_disabled_flags(flags), nest_lock, ip, 0, 0); current->lockdep_recursion = 0; raw_local_irq_restore(flags); } diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c index 32244186f1f2..8ef1919d63b2 100644 --- a/kernel/locking/locktorture.c +++ b/kernel/locking/locktorture.c @@ -17,12 +17,14 @@ * * Copyright (C) IBM Corporation, 2014 * - * Author: Paul E. McKenney <paulmck@us.ibm.com> + * Authors: Paul E. McKenney <paulmck@us.ibm.com> + * Davidlohr Bueso <dave@stgolabs.net> * Based on kernel/rcu/torture.c. */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/kthread.h> +#include <linux/sched/rt.h> #include <linux/spinlock.h> #include <linux/rwlock.h> #include <linux/mutex.h> @@ -34,6 +36,7 @@ #include <linux/moduleparam.h> #include <linux/delay.h> #include <linux/slab.h> +#include <linux/percpu-rwsem.h> #include <linux/torture.h> MODULE_LICENSE("GPL"); @@ -91,11 +94,13 @@ struct lock_torture_ops { void (*init)(void); int (*writelock)(void); void (*write_delay)(struct torture_random_state *trsp); + void (*task_boost)(struct torture_random_state *trsp); void (*writeunlock)(void); int (*readlock)(void); void (*read_delay)(struct torture_random_state *trsp); void (*readunlock)(void); - unsigned long flags; + + unsigned long flags; /* for irq spinlocks */ const char *name; }; @@ -139,9 +144,15 @@ static void torture_lock_busted_write_unlock(void) /* BUGGY, do not use in real life!!! */ } +static void torture_boost_dummy(struct torture_random_state *trsp) +{ + /* Only rtmutexes care about priority */ +} + static struct lock_torture_ops lock_busted_ops = { .writelock = torture_lock_busted_write_lock, .write_delay = torture_lock_busted_write_delay, + .task_boost = torture_boost_dummy, .writeunlock = torture_lock_busted_write_unlock, .readlock = NULL, .read_delay = NULL, @@ -185,6 +196,7 @@ static void torture_spin_lock_write_unlock(void) __releases(torture_spinlock) static struct lock_torture_ops spin_lock_ops = { .writelock = torture_spin_lock_write_lock, .write_delay = torture_spin_lock_write_delay, + .task_boost = torture_boost_dummy, .writeunlock = torture_spin_lock_write_unlock, .readlock = NULL, .read_delay = NULL, @@ -211,6 +223,7 @@ __releases(torture_spinlock) static struct lock_torture_ops spin_lock_irq_ops = { .writelock = torture_spin_lock_write_lock_irq, .write_delay = torture_spin_lock_write_delay, + .task_boost = torture_boost_dummy, .writeunlock = torture_lock_spin_write_unlock_irq, .readlock = NULL, .read_delay = NULL, @@ -275,6 +288,7 @@ static void torture_rwlock_read_unlock(void) __releases(torture_rwlock) static struct lock_torture_ops rw_lock_ops = { .writelock = torture_rwlock_write_lock, .write_delay = torture_rwlock_write_delay, + .task_boost = torture_boost_dummy, .writeunlock = torture_rwlock_write_unlock, .readlock = torture_rwlock_read_lock, .read_delay = torture_rwlock_read_delay, @@ -315,6 +329,7 @@ __releases(torture_rwlock) static struct lock_torture_ops rw_lock_irq_ops = { .writelock = torture_rwlock_write_lock_irq, .write_delay = torture_rwlock_write_delay, + .task_boost = torture_boost_dummy, .writeunlock = torture_rwlock_write_unlock_irq, .readlock = torture_rwlock_read_lock_irq, .read_delay = torture_rwlock_read_delay, @@ -354,6 +369,7 @@ static void torture_mutex_unlock(void) __releases(torture_mutex) static struct lock_torture_ops mutex_lock_ops = { .writelock = torture_mutex_lock, .write_delay = torture_mutex_delay, + .task_boost = torture_boost_dummy, .writeunlock = torture_mutex_unlock, .readlock = NULL, .read_delay = NULL, @@ -361,6 +377,90 @@ static struct lock_torture_ops mutex_lock_ops = { .name = "mutex_lock" }; +#ifdef CONFIG_RT_MUTEXES +static DEFINE_RT_MUTEX(torture_rtmutex); + +static int torture_rtmutex_lock(void) __acquires(torture_rtmutex) +{ + rt_mutex_lock(&torture_rtmutex); + return 0; +} + +static void torture_rtmutex_boost(struct torture_random_state *trsp) +{ + int policy; + struct sched_param param; + const unsigned int factor = 50000; /* yes, quite arbitrary */ + + if (!rt_task(current)) { + /* + * (1) Boost priority once every ~50k operations. When the + * task tries to take the lock, the rtmutex it will account + * for the new priority, and do any corresponding pi-dance. + */ + if (!(torture_random(trsp) % + (cxt.nrealwriters_stress * factor))) { + policy = SCHED_FIFO; + param.sched_priority = MAX_RT_PRIO - 1; + } else /* common case, do nothing */ + return; + } else { + /* + * The task will remain boosted for another ~500k operations, + * then restored back to its original prio, and so forth. + * + * When @trsp is nil, we want to force-reset the task for + * stopping the kthread. + */ + if (!trsp || !(torture_random(trsp) % + (cxt.nrealwriters_stress * factor * 2))) { + policy = SCHED_NORMAL; + param.sched_priority = 0; + } else /* common case, do nothing */ + return; + } + + sched_setscheduler_nocheck(current, policy, ¶m); +} + +static void torture_rtmutex_delay(struct torture_random_state *trsp) +{ + const unsigned long shortdelay_us = 2; + const unsigned long longdelay_ms = 100; + + /* + * We want a short delay mostly to emulate likely code, and + * we want a long delay occasionally to force massive contention. + */ + if (!(torture_random(trsp) % + (cxt.nrealwriters_stress * 2000 * longdelay_ms))) + mdelay(longdelay_ms); + if (!(torture_random(trsp) % + (cxt.nrealwriters_stress * 2 * shortdelay_us))) + udelay(shortdelay_us); +#ifdef CONFIG_PREEMPT + if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) + preempt_schedule(); /* Allow test to be preempted. */ +#endif +} + +static void torture_rtmutex_unlock(void) __releases(torture_rtmutex) +{ + rt_mutex_unlock(&torture_rtmutex); +} + +static struct lock_torture_ops rtmutex_lock_ops = { + .writelock = torture_rtmutex_lock, + .write_delay = torture_rtmutex_delay, + .task_boost = torture_rtmutex_boost, + .writeunlock = torture_rtmutex_unlock, + .readlock = NULL, + .read_delay = NULL, + .readunlock = NULL, + .name = "rtmutex_lock" +}; +#endif + static DECLARE_RWSEM(torture_rwsem); static int torture_rwsem_down_write(void) __acquires(torture_rwsem) { @@ -419,6 +519,7 @@ static void torture_rwsem_up_read(void) __releases(torture_rwsem) static struct lock_torture_ops rwsem_lock_ops = { .writelock = torture_rwsem_down_write, .write_delay = torture_rwsem_write_delay, + .task_boost = torture_boost_dummy, .writeunlock = torture_rwsem_up_write, .readlock = torture_rwsem_down_read, .read_delay = torture_rwsem_read_delay, @@ -426,6 +527,48 @@ static struct lock_torture_ops rwsem_lock_ops = { .name = "rwsem_lock" }; +#include <linux/percpu-rwsem.h> +static struct percpu_rw_semaphore pcpu_rwsem; + +void torture_percpu_rwsem_init(void) +{ + BUG_ON(percpu_init_rwsem(&pcpu_rwsem)); +} + +static int torture_percpu_rwsem_down_write(void) __acquires(pcpu_rwsem) +{ + percpu_down_write(&pcpu_rwsem); + return 0; +} + +static void torture_percpu_rwsem_up_write(void) __releases(pcpu_rwsem) +{ + percpu_up_write(&pcpu_rwsem); +} + +static int torture_percpu_rwsem_down_read(void) __acquires(pcpu_rwsem) +{ + percpu_down_read(&pcpu_rwsem); + return 0; +} + +static void torture_percpu_rwsem_up_read(void) __releases(pcpu_rwsem) +{ + percpu_up_read(&pcpu_rwsem); +} + +static struct lock_torture_ops percpu_rwsem_lock_ops = { + .init = torture_percpu_rwsem_init, + .writelock = torture_percpu_rwsem_down_write, + .write_delay = torture_rwsem_write_delay, + .task_boost = torture_boost_dummy, + .writeunlock = torture_percpu_rwsem_up_write, + .readlock = torture_percpu_rwsem_down_read, + .read_delay = torture_rwsem_read_delay, + .readunlock = torture_percpu_rwsem_up_read, + .name = "percpu_rwsem_lock" +}; + /* * Lock torture writer kthread. Repeatedly acquires and releases * the lock, checking for duplicate acquisitions. @@ -442,6 +585,7 @@ static int lock_torture_writer(void *arg) if ((torture_random(&rand) & 0xfffff) == 0) schedule_timeout_uninterruptible(1); + cxt.cur_ops->task_boost(&rand); cxt.cur_ops->writelock(); if (WARN_ON_ONCE(lock_is_write_held)) lwsp->n_lock_fail++; @@ -456,6 +600,8 @@ static int lock_torture_writer(void *arg) stutter_wait("lock_torture_writer"); } while (!torture_must_stop()); + + cxt.cur_ops->task_boost(NULL); /* reset prio */ torture_kthread_stopping("lock_torture_writer"); return 0; } @@ -642,7 +788,11 @@ static int __init lock_torture_init(void) &spin_lock_ops, &spin_lock_irq_ops, &rw_lock_ops, &rw_lock_irq_ops, &mutex_lock_ops, +#ifdef CONFIG_RT_MUTEXES + &rtmutex_lock_ops, +#endif &rwsem_lock_ops, + &percpu_rwsem_lock_ops, }; if (!torture_init_begin(torture_type, verbose, &torture_runnable)) @@ -661,11 +811,11 @@ static int __init lock_torture_init(void) for (i = 0; i < ARRAY_SIZE(torture_ops); i++) pr_alert(" %s", torture_ops[i]->name); pr_alert("\n"); - torture_init_end(); - return -EINVAL; + firsterr = -EINVAL; + goto unwind; } if (cxt.cur_ops->init) - cxt.cur_ops->init(); /* no "goto unwind" prior to this point!!! */ + cxt.cur_ops->init(); if (nwriters_stress >= 0) cxt.nrealwriters_stress = nwriters_stress; @@ -676,6 +826,10 @@ static int __init lock_torture_init(void) if (strncmp(torture_type, "mutex", 5) == 0) cxt.debug_lock = true; #endif +#ifdef CONFIG_DEBUG_RT_MUTEXES + if (strncmp(torture_type, "rtmutex", 7) == 0) + cxt.debug_lock = true; +#endif #ifdef CONFIG_DEBUG_SPINLOCK if ((strncmp(torture_type, "spin", 4) == 0) || (strncmp(torture_type, "rw_lock", 7) == 0)) diff --git a/kernel/locking/mcs_spinlock.h b/kernel/locking/mcs_spinlock.h index fd91aaa4554c..5b9102a47ea5 100644 --- a/kernel/locking/mcs_spinlock.h +++ b/kernel/locking/mcs_spinlock.h @@ -67,7 +67,7 @@ void mcs_spin_lock(struct mcs_spinlock **lock, struct mcs_spinlock *node) node->locked = 0; node->next = NULL; - prev = xchg(lock, node); + prev = xchg_acquire(lock, node); if (likely(prev == NULL)) { /* * Lock acquired, don't need to set node->locked to 1. Threads @@ -98,7 +98,7 @@ void mcs_spin_unlock(struct mcs_spinlock **lock, struct mcs_spinlock *node) /* * Release the lock by setting it to NULL */ - if (likely(cmpxchg(lock, node, NULL) == node)) + if (likely(cmpxchg_release(lock, node, NULL) == node)) return; /* Wait until the next pointer is set */ while (!(next = READ_ONCE(node->next))) diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index 4cccea6b8934..0551c219c40e 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -277,7 +277,7 @@ static inline int mutex_can_spin_on_owner(struct mutex *lock) static inline bool mutex_try_to_acquire(struct mutex *lock) { return !mutex_is_locked(lock) && - (atomic_cmpxchg(&lock->count, 1, 0) == 1); + (atomic_cmpxchg_acquire(&lock->count, 1, 0) == 1); } /* @@ -529,7 +529,8 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, * Once more, try to acquire the lock. Only try-lock the mutex if * it is unlocked to reduce unnecessary xchg() operations. */ - if (!mutex_is_locked(lock) && (atomic_xchg(&lock->count, 0) == 1)) + if (!mutex_is_locked(lock) && + (atomic_xchg_acquire(&lock->count, 0) == 1)) goto skip_wait; debug_mutex_lock_common(lock, &waiter); @@ -553,7 +554,7 @@ __mutex_lock_common(struct mutex *lock, long state, unsigned int subclass, * non-negative in order to avoid unnecessary xchg operations: */ if (atomic_read(&lock->count) >= 0 && - (atomic_xchg(&lock->count, -1) == 1)) + (atomic_xchg_acquire(&lock->count, -1) == 1)) break; /* @@ -867,7 +868,7 @@ static inline int __mutex_trylock_slowpath(atomic_t *lock_count) spin_lock_mutex(&lock->wait_lock, flags); - prev = atomic_xchg(&lock->count, -1); + prev = atomic_xchg_acquire(&lock->count, -1); if (likely(prev == 1)) { mutex_set_owner(lock); mutex_acquire(&lock->dep_map, 0, 1, _RET_IP_); diff --git a/kernel/locking/osq_lock.c b/kernel/locking/osq_lock.c index dc85ee23a26f..d092a0c9c2d4 100644 --- a/kernel/locking/osq_lock.c +++ b/kernel/locking/osq_lock.c @@ -50,7 +50,7 @@ osq_wait_next(struct optimistic_spin_queue *lock, for (;;) { if (atomic_read(&lock->tail) == curr && - atomic_cmpxchg(&lock->tail, curr, old) == curr) { + atomic_cmpxchg_acquire(&lock->tail, curr, old) == curr) { /* * We were the last queued, we moved @lock back. @prev * will now observe @lock and will complete its @@ -92,7 +92,11 @@ bool osq_lock(struct optimistic_spin_queue *lock) node->next = NULL; node->cpu = curr; - old = atomic_xchg(&lock->tail, curr); + /* + * ACQUIRE semantics, pairs with corresponding RELEASE + * in unlock() uncontended, or fastpath. + */ + old = atomic_xchg_acquire(&lock->tail, curr); if (old == OSQ_UNLOCKED_VAL) return true; @@ -184,7 +188,8 @@ void osq_unlock(struct optimistic_spin_queue *lock) /* * Fast path for the uncontended case. */ - if (likely(atomic_cmpxchg(&lock->tail, curr, OSQ_UNLOCKED_VAL) == curr)) + if (likely(atomic_cmpxchg_release(&lock->tail, curr, + OSQ_UNLOCKED_VAL) == curr)) return; /* diff --git a/kernel/locking/percpu-rwsem.c b/kernel/locking/percpu-rwsem.c index f32567254867..f231e0bb311c 100644 --- a/kernel/locking/percpu-rwsem.c +++ b/kernel/locking/percpu-rwsem.c @@ -17,50 +17,43 @@ int __percpu_init_rwsem(struct percpu_rw_semaphore *brw, /* ->rw_sem represents the whole percpu_rw_semaphore for lockdep */ __init_rwsem(&brw->rw_sem, name, rwsem_key); - atomic_set(&brw->write_ctr, 0); + rcu_sync_init(&brw->rss, RCU_SCHED_SYNC); atomic_set(&brw->slow_read_ctr, 0); init_waitqueue_head(&brw->write_waitq); return 0; } +EXPORT_SYMBOL_GPL(__percpu_init_rwsem); void percpu_free_rwsem(struct percpu_rw_semaphore *brw) { + /* + * XXX: temporary kludge. The error path in alloc_super() + * assumes that percpu_free_rwsem() is safe after kzalloc(). + */ + if (!brw->fast_read_ctr) + return; + + rcu_sync_dtor(&brw->rss); free_percpu(brw->fast_read_ctr); brw->fast_read_ctr = NULL; /* catch use after free bugs */ } /* - * This is the fast-path for down_read/up_read, it only needs to ensure - * there is no pending writer (atomic_read(write_ctr) == 0) and inc/dec the - * fast per-cpu counter. The writer uses synchronize_sched_expedited() to - * serialize with the preempt-disabled section below. - * - * The nontrivial part is that we should guarantee acquire/release semantics - * in case when - * - * R_W: down_write() comes after up_read(), the writer should see all - * changes done by the reader - * or - * W_R: down_read() comes after up_write(), the reader should see all - * changes done by the writer + * This is the fast-path for down_read/up_read. If it succeeds we rely + * on the barriers provided by rcu_sync_enter/exit; see the comments in + * percpu_down_write() and percpu_up_write(). * * If this helper fails the callers rely on the normal rw_semaphore and * atomic_dec_and_test(), so in this case we have the necessary barriers. - * - * But if it succeeds we do not have any barriers, atomic_read(write_ctr) or - * __this_cpu_add() below can be reordered with any LOAD/STORE done by the - * reader inside the critical section. See the comments in down_write and - * up_write below. */ static bool update_fast_ctr(struct percpu_rw_semaphore *brw, unsigned int val) { - bool success = false; + bool success; preempt_disable(); - if (likely(!atomic_read(&brw->write_ctr))) { + success = rcu_sync_is_idle(&brw->rss); + if (likely(success)) __this_cpu_add(*brw->fast_read_ctr, val); - success = true; - } preempt_enable(); return success; @@ -77,16 +70,17 @@ static bool update_fast_ctr(struct percpu_rw_semaphore *brw, unsigned int val) void percpu_down_read(struct percpu_rw_semaphore *brw) { might_sleep(); - if (likely(update_fast_ctr(brw, +1))) { - rwsem_acquire_read(&brw->rw_sem.dep_map, 0, 0, _RET_IP_); + rwsem_acquire_read(&brw->rw_sem.dep_map, 0, 0, _RET_IP_); + + if (likely(update_fast_ctr(brw, +1))) return; - } - down_read(&brw->rw_sem); + /* Avoid rwsem_acquire_read() and rwsem_release() */ + __down_read(&brw->rw_sem); atomic_inc(&brw->slow_read_ctr); - /* avoid up_read()->rwsem_release() */ __up_read(&brw->rw_sem); } +EXPORT_SYMBOL_GPL(percpu_down_read); int percpu_down_read_trylock(struct percpu_rw_semaphore *brw) { @@ -112,6 +106,7 @@ void percpu_up_read(struct percpu_rw_semaphore *brw) if (atomic_dec_and_test(&brw->slow_read_ctr)) wake_up_all(&brw->write_waitq); } +EXPORT_SYMBOL_GPL(percpu_up_read); static int clear_fast_ctr(struct percpu_rw_semaphore *brw) { @@ -126,33 +121,17 @@ static int clear_fast_ctr(struct percpu_rw_semaphore *brw) return sum; } -/* - * A writer increments ->write_ctr to force the readers to switch to the - * slow mode, note the atomic_read() check in update_fast_ctr(). - * - * After that the readers can only inc/dec the slow ->slow_read_ctr counter, - * ->fast_read_ctr is stable. Once the writer moves its sum into the slow - * counter it represents the number of active readers. - * - * Finally the writer takes ->rw_sem for writing and blocks the new readers, - * then waits until the slow counter becomes zero. - */ void percpu_down_write(struct percpu_rw_semaphore *brw) { - /* tell update_fast_ctr() there is a pending writer */ - atomic_inc(&brw->write_ctr); /* - * 1. Ensures that write_ctr != 0 is visible to any down_read/up_read - * so that update_fast_ctr() can't succeed. - * - * 2. Ensures we see the result of every previous this_cpu_add() in - * update_fast_ctr(). + * Make rcu_sync_is_idle() == F and thus disable the fast-path in + * percpu_down_read() and percpu_up_read(), and wait for gp pass. * - * 3. Ensures that if any reader has exited its critical section via - * fast-path, it executes a full memory barrier before we return. - * See R_W case in the comment above update_fast_ctr(). + * The latter synchronises us with the preceding readers which used + * the fast-past, so we can not miss the result of __this_cpu_add() + * or anything else inside their criticial sections. */ - synchronize_sched_expedited(); + rcu_sync_enter(&brw->rss); /* exclude other writers, and block the new readers completely */ down_write(&brw->rw_sem); @@ -163,16 +142,17 @@ void percpu_down_write(struct percpu_rw_semaphore *brw) /* wait for all readers to complete their percpu_up_read() */ wait_event(brw->write_waitq, !atomic_read(&brw->slow_read_ctr)); } +EXPORT_SYMBOL_GPL(percpu_down_write); void percpu_up_write(struct percpu_rw_semaphore *brw) { /* release the lock, but the readers can't use the fast-path */ up_write(&brw->rw_sem); /* - * Insert the barrier before the next fast-path in down_read, - * see W_R case in the comment above update_fast_ctr(). + * Enable the fast-path in percpu_down_read() and percpu_up_read() + * but only after another gp pass; this adds the necessary barrier + * to ensure the reader can't miss the changes done by us. */ - synchronize_sched_expedited(); - /* the last writer unblocks update_fast_ctr() */ - atomic_dec(&brw->write_ctr); + rcu_sync_exit(&brw->rss); } +EXPORT_SYMBOL_GPL(percpu_up_write); diff --git a/kernel/locking/qrwlock.c b/kernel/locking/qrwlock.c index f17a3e3b3550..fec082338668 100644 --- a/kernel/locking/qrwlock.c +++ b/kernel/locking/qrwlock.c @@ -86,7 +86,7 @@ void queued_read_lock_slowpath(struct qrwlock *lock, u32 cnts) /* * Put the reader into the wait queue */ - arch_spin_lock(&lock->lock); + arch_spin_lock(&lock->wait_lock); /* * The ACQUIRE semantics of the following spinning code ensure @@ -99,7 +99,7 @@ void queued_read_lock_slowpath(struct qrwlock *lock, u32 cnts) /* * Signal the next one in queue to become queue head */ - arch_spin_unlock(&lock->lock); + arch_spin_unlock(&lock->wait_lock); } EXPORT_SYMBOL(queued_read_lock_slowpath); @@ -112,7 +112,7 @@ void queued_write_lock_slowpath(struct qrwlock *lock) u32 cnts; /* Put the writer into the wait queue */ - arch_spin_lock(&lock->lock); + arch_spin_lock(&lock->wait_lock); /* Try to acquire the lock directly if no reader is present */ if (!atomic_read(&lock->cnts) && @@ -144,6 +144,6 @@ void queued_write_lock_slowpath(struct qrwlock *lock) cpu_relax_lowlatency(); } unlock: - arch_spin_unlock(&lock->lock); + arch_spin_unlock(&lock->wait_lock); } EXPORT_SYMBOL(queued_write_lock_slowpath); diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h index c8e6e9a596f5..f0450ff4829b 100644 --- a/kernel/locking/qspinlock_paravirt.h +++ b/kernel/locking/qspinlock_paravirt.h @@ -267,7 +267,6 @@ static void pv_wait_head(struct qspinlock *lock, struct mcs_spinlock *node) } if (!lp) { /* ONCE */ - WRITE_ONCE(pn->state, vcpu_hashed); lp = pv_hash(lock, pn); /* @@ -275,11 +274,9 @@ static void pv_wait_head(struct qspinlock *lock, struct mcs_spinlock *node) * when we observe _Q_SLOW_VAL in __pv_queued_spin_unlock() * we'll be sure to be able to observe our hash entry. * - * [S] pn->state * [S] <hash> [Rmw] l->locked == _Q_SLOW_VAL * MB RMB * [RmW] l->locked = _Q_SLOW_VAL [L] <unhash> - * [L] pn->state * * Matches the smp_rmb() in __pv_queued_spin_unlock(). */ @@ -364,8 +361,7 @@ __visible void __pv_queued_spin_unlock(struct qspinlock *lock) * vCPU is harmless other than the additional latency in completing * the unlock. */ - if (READ_ONCE(node->state) == vcpu_hashed) - pv_kick(node->cpu); + pv_kick(node->cpu); } /* * Include the architecture specific callee-save thunk of the diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 7781d801212f..8251e75dd9c0 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -74,14 +74,23 @@ static void fixup_rt_mutex_waiters(struct rt_mutex *lock) * set up. */ #ifndef CONFIG_DEBUG_RT_MUTEXES -# define rt_mutex_cmpxchg(l,c,n) (cmpxchg(&l->owner, c, n) == c) +# define rt_mutex_cmpxchg_relaxed(l,c,n) (cmpxchg_relaxed(&l->owner, c, n) == c) +# define rt_mutex_cmpxchg_acquire(l,c,n) (cmpxchg_acquire(&l->owner, c, n) == c) +# define rt_mutex_cmpxchg_release(l,c,n) (cmpxchg_release(&l->owner, c, n) == c) + +/* + * Callers must hold the ->wait_lock -- which is the whole purpose as we force + * all future threads that attempt to [Rmw] the lock to the slowpath. As such + * relaxed semantics suffice. + */ static inline void mark_rt_mutex_waiters(struct rt_mutex *lock) { unsigned long owner, *p = (unsigned long *) &lock->owner; do { owner = *p; - } while (cmpxchg(p, owner, owner | RT_MUTEX_HAS_WAITERS) != owner); + } while (cmpxchg_relaxed(p, owner, + owner | RT_MUTEX_HAS_WAITERS) != owner); } /* @@ -121,11 +130,14 @@ static inline bool unlock_rt_mutex_safe(struct rt_mutex *lock) * lock(wait_lock); * acquire(lock); */ - return rt_mutex_cmpxchg(lock, owner, NULL); + return rt_mutex_cmpxchg_release(lock, owner, NULL); } #else -# define rt_mutex_cmpxchg(l,c,n) (0) +# define rt_mutex_cmpxchg_relaxed(l,c,n) (0) +# define rt_mutex_cmpxchg_acquire(l,c,n) (0) +# define rt_mutex_cmpxchg_release(l,c,n) (0) + static inline void mark_rt_mutex_waiters(struct rt_mutex *lock) { lock->owner = (struct task_struct *) @@ -158,7 +170,8 @@ rt_mutex_waiter_less(struct rt_mutex_waiter *left, * then right waiter has a dl_prio() too. */ if (dl_prio(left->prio)) - return (left->task->dl.deadline < right->task->dl.deadline); + return dl_time_before(left->task->dl.deadline, + right->task->dl.deadline); return 0; } @@ -1321,7 +1334,7 @@ rt_mutex_fastlock(struct rt_mutex *lock, int state, struct hrtimer_sleeper *timeout, enum rtmutex_chainwalk chwalk)) { - if (likely(rt_mutex_cmpxchg(lock, NULL, current))) { + if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) { rt_mutex_deadlock_account_lock(lock, current); return 0; } else @@ -1337,7 +1350,7 @@ rt_mutex_timed_fastlock(struct rt_mutex *lock, int state, enum rtmutex_chainwalk chwalk)) { if (chwalk == RT_MUTEX_MIN_CHAINWALK && - likely(rt_mutex_cmpxchg(lock, NULL, current))) { + likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) { rt_mutex_deadlock_account_lock(lock, current); return 0; } else @@ -1348,7 +1361,7 @@ static inline int rt_mutex_fasttrylock(struct rt_mutex *lock, int (*slowfn)(struct rt_mutex *lock)) { - if (likely(rt_mutex_cmpxchg(lock, NULL, current))) { + if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) { rt_mutex_deadlock_account_lock(lock, current); return 1; } @@ -1362,7 +1375,7 @@ rt_mutex_fastunlock(struct rt_mutex *lock, { WAKE_Q(wake_q); - if (likely(rt_mutex_cmpxchg(lock, current, NULL))) { + if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) { rt_mutex_deadlock_account_unlock(current); } else { @@ -1484,7 +1497,7 @@ EXPORT_SYMBOL_GPL(rt_mutex_unlock); bool __sched rt_mutex_futex_unlock(struct rt_mutex *lock, struct wake_q_head *wqh) { - if (likely(rt_mutex_cmpxchg(lock, current, NULL))) { + if (likely(rt_mutex_cmpxchg_release(lock, current, NULL))) { rt_mutex_deadlock_account_unlock(current); return false; } diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c index 0f189714e457..a4d4de05b2d1 100644 --- a/kernel/locking/rwsem-xadd.c +++ b/kernel/locking/rwsem-xadd.c @@ -262,7 +262,7 @@ static inline bool rwsem_try_write_lock(long count, struct rw_semaphore *sem) * to reduce unnecessary expensive cmpxchg() operations. */ if (count == RWSEM_WAITING_BIAS && - cmpxchg(&sem->count, RWSEM_WAITING_BIAS, + cmpxchg_acquire(&sem->count, RWSEM_WAITING_BIAS, RWSEM_ACTIVE_WRITE_BIAS) == RWSEM_WAITING_BIAS) { if (!list_is_singular(&sem->wait_list)) rwsem_atomic_update(RWSEM_WAITING_BIAS, sem); @@ -285,7 +285,8 @@ static inline bool rwsem_try_write_lock_unqueued(struct rw_semaphore *sem) if (!(count == 0 || count == RWSEM_WAITING_BIAS)) return false; - old = cmpxchg(&sem->count, count, count + RWSEM_ACTIVE_WRITE_BIAS); + old = cmpxchg_acquire(&sem->count, count, + count + RWSEM_ACTIVE_WRITE_BIAS); if (old == count) { rwsem_set_owner(sem); return true; diff --git a/kernel/memremap.c b/kernel/memremap.c index 72b0c66628b6..7658d32c5c78 100644 --- a/kernel/memremap.c +++ b/kernel/memremap.c @@ -24,6 +24,16 @@ __weak void __iomem *ioremap_cache(resource_size_t offset, unsigned long size) } #endif +static void *try_ram_remap(resource_size_t offset, size_t size) +{ + struct page *page = pfn_to_page(offset >> PAGE_SHIFT); + + /* In the simple case just return the existing linear address */ + if (!PageHighMem(page)) + return __va(offset); + return NULL; /* fallback to ioremap_cache */ +} + /** * memremap() - remap an iomem_resource as cacheable memory * @offset: iomem resource start address @@ -66,8 +76,8 @@ void *memremap(resource_size_t offset, size_t size, unsigned long flags) * the requested range is potentially in "System RAM" */ if (is_ram == REGION_INTERSECTS) - addr = __va(offset); - else + addr = try_ram_remap(offset, size); + if (!addr) addr = ioremap_cache(offset, size); } @@ -114,9 +124,10 @@ void *devm_memremap(struct device *dev, resource_size_t offset, { void **ptr, *addr; - ptr = devres_alloc(devm_memremap_release, sizeof(*ptr), GFP_KERNEL); + ptr = devres_alloc_node(devm_memremap_release, sizeof(*ptr), GFP_KERNEL, + dev_to_node(dev)); if (!ptr) - return NULL; + return ERR_PTR(-ENOMEM); addr = memremap(offset, size, flags); if (addr) { @@ -131,9 +142,8 @@ EXPORT_SYMBOL(devm_memremap); void devm_memunmap(struct device *dev, void *addr) { - WARN_ON(devres_destroy(dev, devm_memremap_release, devm_memremap_match, - addr)); - memunmap(addr); + WARN_ON(devres_release(dev, devm_memremap_release, + devm_memremap_match, addr)); } EXPORT_SYMBOL(devm_memunmap); @@ -166,8 +176,8 @@ void *devm_memremap_pages(struct device *dev, struct resource *res) if (is_ram == REGION_INTERSECTS) return __va(res->start); - page_map = devres_alloc(devm_memremap_pages_release, - sizeof(*page_map), GFP_KERNEL); + page_map = devres_alloc_node(devm_memremap_pages_release, + sizeof(*page_map), GFP_KERNEL, dev_to_node(dev)); if (!page_map) return ERR_PTR(-ENOMEM); @@ -175,7 +185,7 @@ void *devm_memremap_pages(struct device *dev, struct resource *res) nid = dev_to_node(dev); if (nid < 0) - nid = 0; + nid = numa_mem_id(); error = arch_add_memory(nid, res->start, resource_size(res), true); if (error) { diff --git a/kernel/module.c b/kernel/module.c index b86b7bf1be38..8f051a106676 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1063,11 +1063,15 @@ void symbol_put_addr(void *addr) if (core_kernel_text(a)) return; - /* module_text_address is safe here: we're supposed to have reference - * to module from symbol_get, so it can't go away. */ + /* + * Even though we hold a reference on the module; we still need to + * disable preemption in order to safely traverse the data structure. + */ + preempt_disable(); modaddr = __module_text_address(a); BUG_ON(!modaddr); module_put(modaddr); + preempt_enable(); } EXPORT_SYMBOL_GPL(symbol_put_addr); diff --git a/kernel/module_signing.c b/kernel/module_signing.c index bd62f5cda746..6528a79d998d 100644 --- a/kernel/module_signing.c +++ b/kernel/module_signing.c @@ -10,6 +10,7 @@ */ #include <linux/kernel.h> +#include <linux/errno.h> #include <keys/system_keyring.h> #include <crypto/public_key.h> #include "module-internal.h" diff --git a/kernel/panic.c b/kernel/panic.c index 04e91ff7560b..4579dbb7ed87 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -23,6 +23,7 @@ #include <linux/sysrq.h> #include <linux/init.h> #include <linux/nmi.h> +#include <linux/console.h> #define PANIC_TIMER_STEP 100 #define PANIC_BLINK_SPD 18 @@ -147,6 +148,15 @@ void panic(const char *fmt, ...) bust_spinlocks(0); + /* + * We may have ended up stopping the CPU holding the lock (in + * smp_send_stop()) while still having some valuable data in the console + * buffer. Try to acquire the lock then release it regardless of the + * result. The release will also print the buffers out. + */ + console_trylock(); + console_unlock(); + if (!panic_blink) panic_blink = no_blink; diff --git a/kernel/params.c b/kernel/params.c index b6554aa71094..a6d6149c0fe6 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -223,7 +223,7 @@ char *parse_args(const char *doing, int (*unknown)(char *param, char *val, const char *doing, void *arg)) { - char *param, *val; + char *param, *val, *err = NULL; /* Chew leading spaces */ args = skip_spaces(args); @@ -238,7 +238,7 @@ char *parse_args(const char *doing, args = next_arg(args, ¶m, &val); /* Stop at -- */ if (!val && strcmp(param, "--") == 0) - return args; + return err ?: args; irq_was_disabled = irqs_disabled(); ret = parse_one(param, val, doing, params, num, min_level, max_level, arg, unknown); @@ -247,24 +247,25 @@ char *parse_args(const char *doing, doing, param); switch (ret) { + case 0: + continue; case -ENOENT: pr_err("%s: Unknown parameter `%s'\n", doing, param); - return ERR_PTR(ret); + break; case -ENOSPC: pr_err("%s: `%s' too large for parameter `%s'\n", doing, val ?: "", param); - return ERR_PTR(ret); - case 0: break; default: pr_err("%s: `%s' invalid for parameter `%s'\n", doing, val ?: "", param); - return ERR_PTR(ret); + break; } + + err = ERR_PTR(ret); } - /* All parsed OK. */ - return NULL; + return err; } /* Lazy bastard, eh? */ @@ -325,10 +326,11 @@ int param_get_charp(char *buffer, const struct kernel_param *kp) } EXPORT_SYMBOL(param_get_charp); -static void param_free_charp(void *arg) +void param_free_charp(void *arg) { maybe_kfree_parameter(*((char **)arg)); } +EXPORT_SYMBOL(param_free_charp); const struct kernel_param_ops param_ops_charp = { .set = param_set_charp, diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 690f78f210f2..b7342a24f559 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -733,7 +733,7 @@ int hibernate(void) * contents of memory is restored from the saved image. * * If this is successful, control reappears in the restored target kernel in - * hibernation_snaphot() which returns to hibernate(). Otherwise, the routine + * hibernation_snapshot() which returns to hibernate(). Otherwise, the routine * attempts to recover gracefully and make the kernel return to the normal mode * of operation. */ diff --git a/kernel/power/main.c b/kernel/power/main.c index 63d395b5df93..b2dd4d999900 100644 --- a/kernel/power/main.c +++ b/kernel/power/main.c @@ -272,6 +272,22 @@ static inline void pm_print_times_init(void) { pm_print_times_enabled = !!initcall_debug; } + +static ssize_t pm_wakeup_irq_show(struct kobject *kobj, + struct kobj_attribute *attr, + char *buf) +{ + return pm_wakeup_irq ? sprintf(buf, "%u\n", pm_wakeup_irq) : -ENODATA; +} + +static ssize_t pm_wakeup_irq_store(struct kobject *kobj, + struct kobj_attribute *attr, + const char *buf, size_t n) +{ + return -EINVAL; +} +power_attr(pm_wakeup_irq); + #else /* !CONFIG_PM_SLEEP_DEBUG */ static inline void pm_print_times_init(void) {} #endif /* CONFIG_PM_SLEEP_DEBUG */ @@ -604,6 +620,7 @@ static struct attribute * g[] = { #endif #ifdef CONFIG_PM_SLEEP_DEBUG &pm_print_times_attr.attr, + &pm_wakeup_irq_attr.attr, #endif #endif #ifdef CONFIG_FREEZER diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 5235dd4e1e2f..3a970604308f 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -1779,7 +1779,7 @@ alloc_highmem_pages(struct memory_bitmap *bm, unsigned int nr_highmem) while (to_alloc-- > 0) { struct page *page; - page = alloc_image_page(__GFP_HIGHMEM); + page = alloc_image_page(__GFP_HIGHMEM|__GFP_KSWAPD_RECLAIM); memory_bm_set_bit(bm, page_to_pfn(page)); } return nr_highmem; diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c index 7e4cda4a8dd9..f9fe133c13e2 100644 --- a/kernel/power/suspend.c +++ b/kernel/power/suspend.c @@ -35,6 +35,9 @@ const char *pm_labels[] = { "mem", "standby", "freeze", NULL }; const char *pm_states[PM_SUSPEND_MAX]; +unsigned int pm_suspend_global_flags; +EXPORT_SYMBOL_GPL(pm_suspend_global_flags); + static const struct platform_suspend_ops *suspend_ops; static const struct platform_freeze_ops *freeze_ops; static DECLARE_WAIT_QUEUE_HEAD(suspend_freeze_wait_head); @@ -493,6 +496,7 @@ static int enter_state(suspend_state_t state) #endif pr_debug("PM: Preparing system for sleep (%s)\n", pm_states[state]); + pm_suspend_clear_flags(); error = suspend_prepare(state); if (error) goto Unlock; diff --git a/kernel/power/swap.c b/kernel/power/swap.c index b2066fb5b10f..12cd989dadf6 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -257,7 +257,7 @@ static int hib_submit_io(int rw, pgoff_t page_off, void *addr, struct bio *bio; int error = 0; - bio = bio_alloc(__GFP_WAIT | __GFP_HIGH, 1); + bio = bio_alloc(__GFP_RECLAIM | __GFP_HIGH, 1); bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9); bio->bi_bdev = hib_resume_bdev; @@ -356,7 +356,7 @@ static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb) return -ENOSPC; if (hb) { - src = (void *)__get_free_page(__GFP_WAIT | __GFP_NOWARN | + src = (void *)__get_free_page(__GFP_RECLAIM | __GFP_NOWARN | __GFP_NORETRY); if (src) { copy_page(src, buf); @@ -364,7 +364,7 @@ static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb) ret = hib_wait_io(hb); /* Free pages */ if (ret) return ret; - src = (void *)__get_free_page(__GFP_WAIT | + src = (void *)__get_free_page(__GFP_RECLAIM | __GFP_NOWARN | __GFP_NORETRY); if (src) { @@ -672,7 +672,7 @@ static int save_image_lzo(struct swap_map_handle *handle, nr_threads = num_online_cpus() - 1; nr_threads = clamp_val(nr_threads, 1, LZO_THREADS); - page = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH); + page = (void *)__get_free_page(__GFP_RECLAIM | __GFP_HIGH); if (!page) { printk(KERN_ERR "PM: Failed to allocate LZO page\n"); ret = -ENOMEM; @@ -975,7 +975,7 @@ static int get_swap_reader(struct swap_map_handle *handle, last = tmp; tmp->map = (struct swap_map_page *) - __get_free_page(__GFP_WAIT | __GFP_HIGH); + __get_free_page(__GFP_RECLAIM | __GFP_HIGH); if (!tmp->map) { release_swap_reader(handle); return -ENOMEM; @@ -1242,9 +1242,9 @@ static int load_image_lzo(struct swap_map_handle *handle, for (i = 0; i < read_pages; i++) { page[i] = (void *)__get_free_page(i < LZO_CMP_PAGES ? - __GFP_WAIT | __GFP_HIGH : - __GFP_WAIT | __GFP_NOWARN | - __GFP_NORETRY); + __GFP_RECLAIM | __GFP_HIGH : + __GFP_RECLAIM | __GFP_NOWARN | + __GFP_NORETRY); if (!page[i]) { if (i < LZO_CMP_PAGES) { diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 8f0324ef72ab..2ce8826f1053 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -269,6 +269,9 @@ static u32 clear_idx; #define PREFIX_MAX 32 #define LOG_LINE_MAX (1024 - PREFIX_MAX) +#define LOG_LEVEL(v) ((v) & 0x07) +#define LOG_FACILITY(v) ((v) >> 3 & 0xff) + /* record buffer */ #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) #define LOG_ALIGN 4 @@ -517,6 +520,7 @@ int check_syslog_permissions(int type, int source) ok: return security_syslog(type); } +EXPORT_SYMBOL_GPL(check_syslog_permissions); static void append_char(char **pp, char *e, char c) { @@ -611,7 +615,6 @@ struct devkmsg_user { static ssize_t devkmsg_write(struct kiocb *iocb, struct iov_iter *from) { char *buf, *line; - int i; int level = default_message_loglevel; int facility = 1; /* LOG_USER */ size_t len = iov_iter_count(from); @@ -641,12 +644,13 @@ static ssize_t devkmsg_write(struct kiocb *iocb, struct iov_iter *from) line = buf; if (line[0] == '<') { char *endp = NULL; + unsigned int u; - i = simple_strtoul(line+1, &endp, 10); + u = simple_strtoul(line + 1, &endp, 10); if (endp && endp[0] == '>') { - level = i & 7; - if (i >> 3) - facility = i >> 3; + level = LOG_LEVEL(u); + if (LOG_FACILITY(u) != 0) + facility = LOG_FACILITY(u); endp++; len -= endp - line; line = endp; diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 787320de68e0..b760bae64cf1 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -1016,6 +1016,11 @@ int ptrace_request(struct task_struct *child, long request, break; } #endif + + case PTRACE_SECCOMP_GET_FILTER: + ret = seccomp_get_filter(child, addr, datavp); + break; + default: break; } diff --git a/kernel/rcu/Makefile b/kernel/rcu/Makefile index 50a808424b06..61a16569ffbf 100644 --- a/kernel/rcu/Makefile +++ b/kernel/rcu/Makefile @@ -1,4 +1,4 @@ -obj-y += update.o +obj-y += update.o sync.o obj-$(CONFIG_SRCU) += srcu.o obj-$(CONFIG_RCU_TORTURE_TEST) += rcutorture.o obj-$(CONFIG_TREE_RCU) += tree.o diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index 77192953dee5..d89328e260df 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -252,7 +252,7 @@ struct rcu_torture_ops { void (*exp_sync)(void); unsigned long (*get_state)(void); void (*cond_sync)(unsigned long oldstate); - void (*call)(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); + call_rcu_func_t call; void (*cb_barrier)(void); void (*fqs)(void); void (*stats)(void); @@ -448,7 +448,7 @@ static void synchronize_rcu_busted(void) } static void -call_rcu_busted(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) +call_rcu_busted(struct rcu_head *head, rcu_callback_t func) { /* This is a deliberate bug for testing purposes only! */ func(head); @@ -523,7 +523,7 @@ static void srcu_torture_synchronize(void) } static void srcu_torture_call(struct rcu_head *head, - void (*func)(struct rcu_head *head)) + rcu_callback_t func) { call_srcu(srcu_ctlp, head, func); } @@ -695,7 +695,7 @@ static bool __maybe_unused torturing_tasks(void) #define RCUTORTURE_TASKS_OPS -static bool torturing_tasks(void) +static bool __maybe_unused torturing_tasks(void) { return false; } @@ -768,7 +768,6 @@ static int rcu_torture_boost(void *arg) } call_rcu_time = jiffies; } - cond_resched_rcu_qs(); stutter_wait("rcu_torture_boost"); if (torture_must_stop()) goto checkwait; @@ -1208,7 +1207,6 @@ rcu_torture_reader(void *arg) __this_cpu_inc(rcu_torture_batch[completed]); preempt_enable(); cur_ops->readunlock(idx); - cond_resched_rcu_qs(); stutter_wait("rcu_torture_reader"); } while (!torture_must_stop()); if (irqreader && cur_ops->irq_capable) { @@ -1742,15 +1740,15 @@ rcu_torture_init(void) for (i = 0; i < ARRAY_SIZE(torture_ops); i++) pr_alert(" %s", torture_ops[i]->name); pr_alert("\n"); - torture_init_end(); - return -EINVAL; + firsterr = -EINVAL; + goto unwind; } if (cur_ops->fqs == NULL && fqs_duration != 0) { pr_alert("rcu-torture: ->fqs NULL and non-zero fqs_duration, fqs disabled.\n"); fqs_duration = 0; } if (cur_ops->init) - cur_ops->init(); /* no "goto unwind" prior to this point!!! */ + cur_ops->init(); if (nreaders >= 0) { nrealreaders = nreaders; diff --git a/kernel/rcu/srcu.c b/kernel/rcu/srcu.c index d3fcb2ec8536..a63a1ea5a41b 100644 --- a/kernel/rcu/srcu.c +++ b/kernel/rcu/srcu.c @@ -298,11 +298,9 @@ int __srcu_read_lock(struct srcu_struct *sp) int idx; idx = READ_ONCE(sp->completed) & 0x1; - preempt_disable(); __this_cpu_inc(sp->per_cpu_ref->c[idx]); smp_mb(); /* B */ /* Avoid leaking the critical section. */ __this_cpu_inc(sp->per_cpu_ref->seq[idx]); - preempt_enable(); return idx; } EXPORT_SYMBOL_GPL(__srcu_read_lock); @@ -387,7 +385,7 @@ static void srcu_flip(struct srcu_struct *sp) * srcu_struct structure. */ void call_srcu(struct srcu_struct *sp, struct rcu_head *head, - void (*func)(struct rcu_head *head)) + rcu_callback_t func) { unsigned long flags; diff --git a/kernel/rcu/sync.c b/kernel/rcu/sync.c new file mode 100644 index 000000000000..be922c9f3d37 --- /dev/null +++ b/kernel/rcu/sync.c @@ -0,0 +1,223 @@ +/* + * RCU-based infrastructure for lightweight reader-writer locking + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, you can access it online at + * http://www.gnu.org/licenses/gpl-2.0.html. + * + * Copyright (c) 2015, Red Hat, Inc. + * + * Author: Oleg Nesterov <oleg@redhat.com> + */ + +#include <linux/rcu_sync.h> +#include <linux/sched.h> + +#ifdef CONFIG_PROVE_RCU +#define __INIT_HELD(func) .held = func, +#else +#define __INIT_HELD(func) +#endif + +static const struct { + void (*sync)(void); + void (*call)(struct rcu_head *, void (*)(struct rcu_head *)); + void (*wait)(void); +#ifdef CONFIG_PROVE_RCU + int (*held)(void); +#endif +} gp_ops[] = { + [RCU_SYNC] = { + .sync = synchronize_rcu, + .call = call_rcu, + .wait = rcu_barrier, + __INIT_HELD(rcu_read_lock_held) + }, + [RCU_SCHED_SYNC] = { + .sync = synchronize_sched, + .call = call_rcu_sched, + .wait = rcu_barrier_sched, + __INIT_HELD(rcu_read_lock_sched_held) + }, + [RCU_BH_SYNC] = { + .sync = synchronize_rcu_bh, + .call = call_rcu_bh, + .wait = rcu_barrier_bh, + __INIT_HELD(rcu_read_lock_bh_held) + }, +}; + +enum { GP_IDLE = 0, GP_PENDING, GP_PASSED }; +enum { CB_IDLE = 0, CB_PENDING, CB_REPLAY }; + +#define rss_lock gp_wait.lock + +#ifdef CONFIG_PROVE_RCU +void rcu_sync_lockdep_assert(struct rcu_sync *rsp) +{ + RCU_LOCKDEP_WARN(!gp_ops[rsp->gp_type].held(), + "suspicious rcu_sync_is_idle() usage"); +} +#endif + +/** + * rcu_sync_init() - Initialize an rcu_sync structure + * @rsp: Pointer to rcu_sync structure to be initialized + * @type: Flavor of RCU with which to synchronize rcu_sync structure + */ +void rcu_sync_init(struct rcu_sync *rsp, enum rcu_sync_type type) +{ + memset(rsp, 0, sizeof(*rsp)); + init_waitqueue_head(&rsp->gp_wait); + rsp->gp_type = type; +} + +/** + * rcu_sync_enter() - Force readers onto slowpath + * @rsp: Pointer to rcu_sync structure to use for synchronization + * + * This function is used by updaters who need readers to make use of + * a slowpath during the update. After this function returns, all + * subsequent calls to rcu_sync_is_idle() will return false, which + * tells readers to stay off their fastpaths. A later call to + * rcu_sync_exit() re-enables reader slowpaths. + * + * When called in isolation, rcu_sync_enter() must wait for a grace + * period, however, closely spaced calls to rcu_sync_enter() can + * optimize away the grace-period wait via a state machine implemented + * by rcu_sync_enter(), rcu_sync_exit(), and rcu_sync_func(). + */ +void rcu_sync_enter(struct rcu_sync *rsp) +{ + bool need_wait, need_sync; + + spin_lock_irq(&rsp->rss_lock); + need_wait = rsp->gp_count++; + need_sync = rsp->gp_state == GP_IDLE; + if (need_sync) + rsp->gp_state = GP_PENDING; + spin_unlock_irq(&rsp->rss_lock); + + BUG_ON(need_wait && need_sync); + + if (need_sync) { + gp_ops[rsp->gp_type].sync(); + rsp->gp_state = GP_PASSED; + wake_up_all(&rsp->gp_wait); + } else if (need_wait) { + wait_event(rsp->gp_wait, rsp->gp_state == GP_PASSED); + } else { + /* + * Possible when there's a pending CB from a rcu_sync_exit(). + * Nobody has yet been allowed the 'fast' path and thus we can + * avoid doing any sync(). The callback will get 'dropped'. + */ + BUG_ON(rsp->gp_state != GP_PASSED); + } +} + +/** + * rcu_sync_func() - Callback function managing reader access to fastpath + * @rsp: Pointer to rcu_sync structure to use for synchronization + * + * This function is passed to one of the call_rcu() functions by + * rcu_sync_exit(), so that it is invoked after a grace period following the + * that invocation of rcu_sync_exit(). It takes action based on events that + * have taken place in the meantime, so that closely spaced rcu_sync_enter() + * and rcu_sync_exit() pairs need not wait for a grace period. + * + * If another rcu_sync_enter() is invoked before the grace period + * ended, reset state to allow the next rcu_sync_exit() to let the + * readers back onto their fastpaths (after a grace period). If both + * another rcu_sync_enter() and its matching rcu_sync_exit() are invoked + * before the grace period ended, re-invoke call_rcu() on behalf of that + * rcu_sync_exit(). Otherwise, set all state back to idle so that readers + * can again use their fastpaths. + */ +static void rcu_sync_func(struct rcu_head *rcu) +{ + struct rcu_sync *rsp = container_of(rcu, struct rcu_sync, cb_head); + unsigned long flags; + + BUG_ON(rsp->gp_state != GP_PASSED); + BUG_ON(rsp->cb_state == CB_IDLE); + + spin_lock_irqsave(&rsp->rss_lock, flags); + if (rsp->gp_count) { + /* + * A new rcu_sync_begin() has happened; drop the callback. + */ + rsp->cb_state = CB_IDLE; + } else if (rsp->cb_state == CB_REPLAY) { + /* + * A new rcu_sync_exit() has happened; requeue the callback + * to catch a later GP. + */ + rsp->cb_state = CB_PENDING; + gp_ops[rsp->gp_type].call(&rsp->cb_head, rcu_sync_func); + } else { + /* + * We're at least a GP after rcu_sync_exit(); eveybody will now + * have observed the write side critical section. Let 'em rip!. + */ + rsp->cb_state = CB_IDLE; + rsp->gp_state = GP_IDLE; + } + spin_unlock_irqrestore(&rsp->rss_lock, flags); +} + +/** + * rcu_sync_exit() - Allow readers back onto fast patch after grace period + * @rsp: Pointer to rcu_sync structure to use for synchronization + * + * This function is used by updaters who have completed, and can therefore + * now allow readers to make use of their fastpaths after a grace period + * has elapsed. After this grace period has completed, all subsequent + * calls to rcu_sync_is_idle() will return true, which tells readers that + * they can once again use their fastpaths. + */ +void rcu_sync_exit(struct rcu_sync *rsp) +{ + spin_lock_irq(&rsp->rss_lock); + if (!--rsp->gp_count) { + if (rsp->cb_state == CB_IDLE) { + rsp->cb_state = CB_PENDING; + gp_ops[rsp->gp_type].call(&rsp->cb_head, rcu_sync_func); + } else if (rsp->cb_state == CB_PENDING) { + rsp->cb_state = CB_REPLAY; + } + } + spin_unlock_irq(&rsp->rss_lock); +} + +/** + * rcu_sync_dtor() - Clean up an rcu_sync structure + * @rsp: Pointer to rcu_sync structure to be cleaned up + */ +void rcu_sync_dtor(struct rcu_sync *rsp) +{ + int cb_state; + + BUG_ON(rsp->gp_count); + + spin_lock_irq(&rsp->rss_lock); + if (rsp->cb_state == CB_REPLAY) + rsp->cb_state = CB_PENDING; + cb_state = rsp->cb_state; + spin_unlock_irq(&rsp->rss_lock); + + if (cb_state != CB_IDLE) { + gp_ops[rsp->gp_type].wait(); + BUG_ON(rsp->cb_state != CB_IDLE); + } +} diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c index d0471056d0af..944b1b491ed8 100644 --- a/kernel/rcu/tiny.c +++ b/kernel/rcu/tiny.c @@ -44,7 +44,7 @@ struct rcu_ctrlblk; static void __rcu_process_callbacks(struct rcu_ctrlblk *rcp); static void rcu_process_callbacks(struct softirq_action *unused); static void __call_rcu(struct rcu_head *head, - void (*func)(struct rcu_head *rcu), + rcu_callback_t func, struct rcu_ctrlblk *rcp); #include "tiny_plugin.h" @@ -203,7 +203,7 @@ EXPORT_SYMBOL_GPL(synchronize_sched); * Helper function for call_rcu() and call_rcu_bh(). */ static void __call_rcu(struct rcu_head *head, - void (*func)(struct rcu_head *rcu), + rcu_callback_t func, struct rcu_ctrlblk *rcp) { unsigned long flags; @@ -229,7 +229,7 @@ static void __call_rcu(struct rcu_head *head, * period. But since we have but one CPU, that would be after any * quiescent state. */ -void call_rcu_sched(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) +void call_rcu_sched(struct rcu_head *head, rcu_callback_t func) { __call_rcu(head, func, &rcu_sched_ctrlblk); } @@ -239,7 +239,7 @@ EXPORT_SYMBOL_GPL(call_rcu_sched); * Post an RCU bottom-half callback to be invoked after any subsequent * quiescent state. */ -void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) +void call_rcu_bh(struct rcu_head *head, rcu_callback_t func) { __call_rcu(head, func, &rcu_bh_ctrlblk); } diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 9f75f25cc5d9..f07343b54fe5 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -71,7 +71,6 @@ MODULE_ALIAS("rcutree"); static struct lock_class_key rcu_node_class[RCU_NUM_LVLS]; static struct lock_class_key rcu_fqs_class[RCU_NUM_LVLS]; static struct lock_class_key rcu_exp_class[RCU_NUM_LVLS]; -static struct lock_class_key rcu_exp_sched_class[RCU_NUM_LVLS]; /* * In order to export the rcu_state name to the tracing tools, it @@ -98,7 +97,7 @@ struct rcu_state sname##_state = { \ .level = { &sname##_state.node[0] }, \ .rda = &sname##_data, \ .call = cr, \ - .fqs_state = RCU_GP_IDLE, \ + .gp_state = RCU_GP_IDLE, \ .gpnum = 0UL - 300UL, \ .completed = 0UL - 300UL, \ .orphan_lock = __RAW_SPIN_LOCK_UNLOCKED(&sname##_state.orphan_lock), \ @@ -161,6 +160,8 @@ static void rcu_cleanup_dead_rnp(struct rcu_node *rnp_leaf); static void rcu_boost_kthread_setaffinity(struct rcu_node *rnp, int outgoingcpu); static void invoke_rcu_core(void); static void invoke_rcu_callbacks(struct rcu_state *rsp, struct rcu_data *rdp); +static void rcu_report_exp_rdp(struct rcu_state *rsp, + struct rcu_data *rdp, bool wake); /* rcuc/rcub kthread realtime priority */ #ifdef CONFIG_RCU_KTHREAD_PRIO @@ -245,21 +246,33 @@ static int rcu_gp_in_progress(struct rcu_state *rsp) */ void rcu_sched_qs(void) { - if (!__this_cpu_read(rcu_sched_data.passed_quiesce)) { + unsigned long flags; + + if (__this_cpu_read(rcu_sched_data.cpu_no_qs.s)) { trace_rcu_grace_period(TPS("rcu_sched"), __this_cpu_read(rcu_sched_data.gpnum), TPS("cpuqs")); - __this_cpu_write(rcu_sched_data.passed_quiesce, 1); + __this_cpu_write(rcu_sched_data.cpu_no_qs.b.norm, false); + if (!__this_cpu_read(rcu_sched_data.cpu_no_qs.b.exp)) + return; + local_irq_save(flags); + if (__this_cpu_read(rcu_sched_data.cpu_no_qs.b.exp)) { + __this_cpu_write(rcu_sched_data.cpu_no_qs.b.exp, false); + rcu_report_exp_rdp(&rcu_sched_state, + this_cpu_ptr(&rcu_sched_data), + true); + } + local_irq_restore(flags); } } void rcu_bh_qs(void) { - if (!__this_cpu_read(rcu_bh_data.passed_quiesce)) { + if (__this_cpu_read(rcu_bh_data.cpu_no_qs.s)) { trace_rcu_grace_period(TPS("rcu_bh"), __this_cpu_read(rcu_bh_data.gpnum), TPS("cpuqs")); - __this_cpu_write(rcu_bh_data.passed_quiesce, 1); + __this_cpu_write(rcu_bh_data.cpu_no_qs.b.norm, false); } } @@ -337,12 +350,14 @@ static void rcu_momentary_dyntick_idle(void) */ void rcu_note_context_switch(void) { + barrier(); /* Avoid RCU read-side critical sections leaking down. */ trace_rcu_utilization(TPS("Start context switch")); rcu_sched_qs(); rcu_preempt_note_context_switch(); if (unlikely(raw_cpu_read(rcu_sched_qs_mask))) rcu_momentary_dyntick_idle(); trace_rcu_utilization(TPS("End context switch")); + barrier(); /* Avoid RCU read-side critical sections leaking up. */ } EXPORT_SYMBOL_GPL(rcu_note_context_switch); @@ -353,12 +368,19 @@ EXPORT_SYMBOL_GPL(rcu_note_context_switch); * RCU flavors in desperate need of a quiescent state, which will normally * be none of them). Either way, do a lightweight quiescent state for * all RCU flavors. + * + * The barrier() calls are redundant in the common case when this is + * called externally, but just in case this is called from within this + * file. + * */ void rcu_all_qs(void) { + barrier(); /* Avoid RCU read-side critical sections leaking down. */ if (unlikely(raw_cpu_read(rcu_sched_qs_mask))) rcu_momentary_dyntick_idle(); this_cpu_inc(rcu_qs_ctr); + barrier(); /* Avoid RCU read-side critical sections leaking up. */ } EXPORT_SYMBOL_GPL(rcu_all_qs); @@ -1744,9 +1766,9 @@ static bool __note_gp_changes(struct rcu_state *rsp, struct rcu_node *rnp, */ rdp->gpnum = rnp->gpnum; trace_rcu_grace_period(rsp->name, rdp->gpnum, TPS("cpustart")); - rdp->passed_quiesce = 0; + rdp->cpu_no_qs.b.norm = true; rdp->rcu_qs_ctr_snap = __this_cpu_read(rcu_qs_ctr); - rdp->qs_pending = !!(rnp->qsmask & rdp->grpmask); + rdp->core_needs_qs = !!(rnp->qsmask & rdp->grpmask); zero_cpu_stall_ticks(rdp); WRITE_ONCE(rdp->gpwrap, false); } @@ -1927,16 +1949,15 @@ static bool rcu_gp_fqs_check_wake(struct rcu_state *rsp, int *gfp) /* * Do one round of quiescent-state forcing. */ -static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in) +static void rcu_gp_fqs(struct rcu_state *rsp, bool first_time) { - int fqs_state = fqs_state_in; bool isidle = false; unsigned long maxj; struct rcu_node *rnp = rcu_get_root(rsp); WRITE_ONCE(rsp->gp_activity, jiffies); rsp->n_force_qs++; - if (fqs_state == RCU_SAVE_DYNTICK) { + if (first_time) { /* Collect dyntick-idle snapshots. */ if (is_sysidle_rcu_state(rsp)) { isidle = true; @@ -1945,7 +1966,6 @@ static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in) force_qs_rnp(rsp, dyntick_save_progress_counter, &isidle, &maxj); rcu_sysidle_report_gp(rsp, isidle, maxj); - fqs_state = RCU_FORCE_QS; } else { /* Handle dyntick-idle and offline CPUs. */ isidle = true; @@ -1959,7 +1979,6 @@ static int rcu_gp_fqs(struct rcu_state *rsp, int fqs_state_in) READ_ONCE(rsp->gp_flags) & ~RCU_GP_FLAG_FQS); raw_spin_unlock_irq(&rnp->lock); } - return fqs_state; } /* @@ -2023,7 +2042,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) /* Declare grace period done. */ WRITE_ONCE(rsp->completed, rsp->gpnum); trace_rcu_grace_period(rsp->name, rsp->completed, TPS("end")); - rsp->fqs_state = RCU_GP_IDLE; + rsp->gp_state = RCU_GP_IDLE; rdp = this_cpu_ptr(rsp->rda); /* Advance CBs to reduce false positives below. */ needgp = rcu_advance_cbs(rsp, rnp, rdp) || needgp; @@ -2041,7 +2060,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp) */ static int __noreturn rcu_gp_kthread(void *arg) { - int fqs_state; + bool first_gp_fqs; int gf; unsigned long j; int ret; @@ -2073,7 +2092,7 @@ static int __noreturn rcu_gp_kthread(void *arg) } /* Handle quiescent-state forcing. */ - fqs_state = RCU_SAVE_DYNTICK; + first_gp_fqs = true; j = jiffies_till_first_fqs; if (j > HZ) { j = HZ; @@ -2101,7 +2120,8 @@ static int __noreturn rcu_gp_kthread(void *arg) trace_rcu_grace_period(rsp->name, READ_ONCE(rsp->gpnum), TPS("fqsstart")); - fqs_state = rcu_gp_fqs(rsp, fqs_state); + rcu_gp_fqs(rsp, first_gp_fqs); + first_gp_fqs = false; trace_rcu_grace_period(rsp->name, READ_ONCE(rsp->gpnum), TPS("fqsend")); @@ -2337,7 +2357,7 @@ rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp) rnp = rdp->mynode; raw_spin_lock_irqsave(&rnp->lock, flags); smp_mb__after_unlock_lock(); - if ((rdp->passed_quiesce == 0 && + if ((rdp->cpu_no_qs.b.norm && rdp->rcu_qs_ctr_snap == __this_cpu_read(rcu_qs_ctr)) || rdp->gpnum != rnp->gpnum || rnp->completed == rnp->gpnum || rdp->gpwrap) { @@ -2348,7 +2368,7 @@ rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp) * We will instead need a new quiescent state that lies * within the current grace period. */ - rdp->passed_quiesce = 0; /* need qs for new gp. */ + rdp->cpu_no_qs.b.norm = true; /* need qs for new gp. */ rdp->rcu_qs_ctr_snap = __this_cpu_read(rcu_qs_ctr); raw_spin_unlock_irqrestore(&rnp->lock, flags); return; @@ -2357,7 +2377,7 @@ rcu_report_qs_rdp(int cpu, struct rcu_state *rsp, struct rcu_data *rdp) if ((rnp->qsmask & mask) == 0) { raw_spin_unlock_irqrestore(&rnp->lock, flags); } else { - rdp->qs_pending = 0; + rdp->core_needs_qs = 0; /* * This GP can't end until cpu checks in, so all of our @@ -2388,14 +2408,14 @@ rcu_check_quiescent_state(struct rcu_state *rsp, struct rcu_data *rdp) * Does this CPU still need to do its part for current grace period? * If no, return and let the other CPUs do their part as well. */ - if (!rdp->qs_pending) + if (!rdp->core_needs_qs) return; /* * Was there a quiescent state since the beginning of the grace * period? If no, then exit and wait for the next call. */ - if (!rdp->passed_quiesce && + if (rdp->cpu_no_qs.b.norm && rdp->rcu_qs_ctr_snap == __this_cpu_read(rcu_qs_ctr)) return; @@ -3017,7 +3037,7 @@ static void rcu_leak_callback(struct rcu_head *rhp) * is expected to specify a CPU. */ static void -__call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu), +__call_rcu(struct rcu_head *head, rcu_callback_t func, struct rcu_state *rsp, int cpu, bool lazy) { unsigned long flags; @@ -3088,7 +3108,7 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu), /* * Queue an RCU-sched callback for invocation after a grace period. */ -void call_rcu_sched(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) +void call_rcu_sched(struct rcu_head *head, rcu_callback_t func) { __call_rcu(head, func, &rcu_sched_state, -1, 0); } @@ -3097,7 +3117,7 @@ EXPORT_SYMBOL_GPL(call_rcu_sched); /* * Queue an RCU callback for invocation after a quicker grace period. */ -void call_rcu_bh(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) +void call_rcu_bh(struct rcu_head *head, rcu_callback_t func) { __call_rcu(head, func, &rcu_bh_state, -1, 0); } @@ -3111,7 +3131,7 @@ EXPORT_SYMBOL_GPL(call_rcu_bh); * function may only be called from __kfree_rcu(). */ void kfree_call_rcu(struct rcu_head *head, - void (*func)(struct rcu_head *rcu)) + rcu_callback_t func) { __call_rcu(head, func, rcu_state_p, -1, 1); } @@ -3379,6 +3399,191 @@ static bool rcu_exp_gp_seq_done(struct rcu_state *rsp, unsigned long s) return rcu_seq_done(&rsp->expedited_sequence, s); } +/* + * Reset the ->expmaskinit values in the rcu_node tree to reflect any + * recent CPU-online activity. Note that these masks are not cleared + * when CPUs go offline, so they reflect the union of all CPUs that have + * ever been online. This means that this function normally takes its + * no-work-to-do fastpath. + */ +static void sync_exp_reset_tree_hotplug(struct rcu_state *rsp) +{ + bool done; + unsigned long flags; + unsigned long mask; + unsigned long oldmask; + int ncpus = READ_ONCE(rsp->ncpus); + struct rcu_node *rnp; + struct rcu_node *rnp_up; + + /* If no new CPUs onlined since last time, nothing to do. */ + if (likely(ncpus == rsp->ncpus_snap)) + return; + rsp->ncpus_snap = ncpus; + + /* + * Each pass through the following loop propagates newly onlined + * CPUs for the current rcu_node structure up the rcu_node tree. + */ + rcu_for_each_leaf_node(rsp, rnp) { + raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); + if (rnp->expmaskinit == rnp->expmaskinitnext) { + raw_spin_unlock_irqrestore(&rnp->lock, flags); + continue; /* No new CPUs, nothing to do. */ + } + + /* Update this node's mask, track old value for propagation. */ + oldmask = rnp->expmaskinit; + rnp->expmaskinit = rnp->expmaskinitnext; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + + /* If was already nonzero, nothing to propagate. */ + if (oldmask) + continue; + + /* Propagate the new CPU up the tree. */ + mask = rnp->grpmask; + rnp_up = rnp->parent; + done = false; + while (rnp_up) { + raw_spin_lock_irqsave(&rnp_up->lock, flags); + smp_mb__after_unlock_lock(); + if (rnp_up->expmaskinit) + done = true; + rnp_up->expmaskinit |= mask; + raw_spin_unlock_irqrestore(&rnp_up->lock, flags); + if (done) + break; + mask = rnp_up->grpmask; + rnp_up = rnp_up->parent; + } + } +} + +/* + * Reset the ->expmask values in the rcu_node tree in preparation for + * a new expedited grace period. + */ +static void __maybe_unused sync_exp_reset_tree(struct rcu_state *rsp) +{ + unsigned long flags; + struct rcu_node *rnp; + + sync_exp_reset_tree_hotplug(rsp); + rcu_for_each_node_breadth_first(rsp, rnp) { + raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); + WARN_ON_ONCE(rnp->expmask); + rnp->expmask = rnp->expmaskinit; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + } +} + +/* + * Return non-zero if there is no RCU expedited grace period in progress + * for the specified rcu_node structure, in other words, if all CPUs and + * tasks covered by the specified rcu_node structure have done their bit + * for the current expedited grace period. Works only for preemptible + * RCU -- other RCU implementation use other means. + * + * Caller must hold the root rcu_node's exp_funnel_mutex. + */ +static int sync_rcu_preempt_exp_done(struct rcu_node *rnp) +{ + return rnp->exp_tasks == NULL && + READ_ONCE(rnp->expmask) == 0; +} + +/* + * Report the exit from RCU read-side critical section for the last task + * that queued itself during or before the current expedited preemptible-RCU + * grace period. This event is reported either to the rcu_node structure on + * which the task was queued or to one of that rcu_node structure's ancestors, + * recursively up the tree. (Calm down, calm down, we do the recursion + * iteratively!) + * + * Caller must hold the root rcu_node's exp_funnel_mutex and the + * specified rcu_node structure's ->lock. + */ +static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, + bool wake, unsigned long flags) + __releases(rnp->lock) +{ + unsigned long mask; + + for (;;) { + if (!sync_rcu_preempt_exp_done(rnp)) { + if (!rnp->expmask) + rcu_initiate_boost(rnp, flags); + else + raw_spin_unlock_irqrestore(&rnp->lock, flags); + break; + } + if (rnp->parent == NULL) { + raw_spin_unlock_irqrestore(&rnp->lock, flags); + if (wake) { + smp_mb(); /* EGP done before wake_up(). */ + wake_up(&rsp->expedited_wq); + } + break; + } + mask = rnp->grpmask; + raw_spin_unlock(&rnp->lock); /* irqs remain disabled */ + rnp = rnp->parent; + raw_spin_lock(&rnp->lock); /* irqs already disabled */ + smp_mb__after_unlock_lock(); + WARN_ON_ONCE(!(rnp->expmask & mask)); + rnp->expmask &= ~mask; + } +} + +/* + * Report expedited quiescent state for specified node. This is a + * lock-acquisition wrapper function for __rcu_report_exp_rnp(). + * + * Caller must hold the root rcu_node's exp_funnel_mutex. + */ +static void __maybe_unused rcu_report_exp_rnp(struct rcu_state *rsp, + struct rcu_node *rnp, bool wake) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); + __rcu_report_exp_rnp(rsp, rnp, wake, flags); +} + +/* + * Report expedited quiescent state for multiple CPUs, all covered by the + * specified leaf rcu_node structure. Caller must hold the root + * rcu_node's exp_funnel_mutex. + */ +static void rcu_report_exp_cpu_mult(struct rcu_state *rsp, struct rcu_node *rnp, + unsigned long mask, bool wake) +{ + unsigned long flags; + + raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); + if (!(rnp->expmask & mask)) { + raw_spin_unlock_irqrestore(&rnp->lock, flags); + return; + } + rnp->expmask &= ~mask; + __rcu_report_exp_rnp(rsp, rnp, wake, flags); /* Releases rnp->lock. */ +} + +/* + * Report expedited quiescent state for specified rcu_data (CPU). + * Caller must hold the root rcu_node's exp_funnel_mutex. + */ +static void rcu_report_exp_rdp(struct rcu_state *rsp, struct rcu_data *rdp, + bool wake) +{ + rcu_report_exp_cpu_mult(rsp, rdp->mynode, rdp->grpmask, wake); +} + /* Common code for synchronize_{rcu,sched}_expedited() work-done checking. */ static bool sync_exp_work_done(struct rcu_state *rsp, struct rcu_node *rnp, struct rcu_data *rdp, @@ -3455,16 +3660,111 @@ static struct rcu_node *exp_funnel_lock(struct rcu_state *rsp, unsigned long s) } /* Invoked on each online non-idle CPU for expedited quiescent state. */ -static int synchronize_sched_expedited_cpu_stop(void *data) +static void sync_sched_exp_handler(void *data) { - struct rcu_data *rdp = data; - struct rcu_state *rsp = rdp->rsp; + struct rcu_data *rdp; + struct rcu_node *rnp; + struct rcu_state *rsp = data; - /* We are here: If we are last, do the wakeup. */ - rdp->exp_done = true; - if (atomic_dec_and_test(&rsp->expedited_need_qs)) - wake_up(&rsp->expedited_wq); - return 0; + rdp = this_cpu_ptr(rsp->rda); + rnp = rdp->mynode; + if (!(READ_ONCE(rnp->expmask) & rdp->grpmask) || + __this_cpu_read(rcu_sched_data.cpu_no_qs.b.exp)) + return; + __this_cpu_write(rcu_sched_data.cpu_no_qs.b.exp, true); + resched_cpu(smp_processor_id()); +} + +/* Send IPI for expedited cleanup if needed at end of CPU-hotplug operation. */ +static void sync_sched_exp_online_cleanup(int cpu) +{ + struct rcu_data *rdp; + int ret; + struct rcu_node *rnp; + struct rcu_state *rsp = &rcu_sched_state; + + rdp = per_cpu_ptr(rsp->rda, cpu); + rnp = rdp->mynode; + if (!(READ_ONCE(rnp->expmask) & rdp->grpmask)) + return; + ret = smp_call_function_single(cpu, sync_sched_exp_handler, rsp, 0); + WARN_ON_ONCE(ret); +} + +/* + * Select the nodes that the upcoming expedited grace period needs + * to wait for. + */ +static void sync_rcu_exp_select_cpus(struct rcu_state *rsp, + smp_call_func_t func) +{ + int cpu; + unsigned long flags; + unsigned long mask; + unsigned long mask_ofl_test; + unsigned long mask_ofl_ipi; + int ret; + struct rcu_node *rnp; + + sync_exp_reset_tree(rsp); + rcu_for_each_leaf_node(rsp, rnp) { + raw_spin_lock_irqsave(&rnp->lock, flags); + smp_mb__after_unlock_lock(); + + /* Each pass checks a CPU for identity, offline, and idle. */ + mask_ofl_test = 0; + for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++) { + struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu); + struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu); + + if (raw_smp_processor_id() == cpu || + !(atomic_add_return(0, &rdtp->dynticks) & 0x1)) + mask_ofl_test |= rdp->grpmask; + } + mask_ofl_ipi = rnp->expmask & ~mask_ofl_test; + + /* + * Need to wait for any blocked tasks as well. Note that + * additional blocking tasks will also block the expedited + * GP until such time as the ->expmask bits are cleared. + */ + if (rcu_preempt_has_tasks(rnp)) + rnp->exp_tasks = rnp->blkd_tasks.next; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + + /* IPI the remaining CPUs for expedited quiescent state. */ + mask = 1; + for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask <<= 1) { + if (!(mask_ofl_ipi & mask)) + continue; +retry_ipi: + ret = smp_call_function_single(cpu, func, rsp, 0); + if (!ret) { + mask_ofl_ipi &= ~mask; + } else { + /* Failed, raced with offline. */ + raw_spin_lock_irqsave(&rnp->lock, flags); + if (cpu_online(cpu) && + (rnp->expmask & mask)) { + raw_spin_unlock_irqrestore(&rnp->lock, + flags); + schedule_timeout_uninterruptible(1); + if (cpu_online(cpu) && + (rnp->expmask & mask)) + goto retry_ipi; + raw_spin_lock_irqsave(&rnp->lock, + flags); + } + if (!(rnp->expmask & mask)) + mask_ofl_ipi &= ~mask; + raw_spin_unlock_irqrestore(&rnp->lock, flags); + } + } + /* Report quiescent states for those that went offline. */ + mask_ofl_test |= mask_ofl_ipi; + if (mask_ofl_test) + rcu_report_exp_cpu_mult(rsp, rnp, mask_ofl_test, false); + } } static void synchronize_sched_expedited_wait(struct rcu_state *rsp) @@ -3472,7 +3772,9 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp) int cpu; unsigned long jiffies_stall; unsigned long jiffies_start; - struct rcu_data *rdp; + unsigned long mask; + struct rcu_node *rnp; + struct rcu_node *rnp_root = rcu_get_root(rsp); int ret; jiffies_stall = rcu_jiffies_till_stall_check(); @@ -3481,33 +3783,43 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp) for (;;) { ret = wait_event_interruptible_timeout( rsp->expedited_wq, - !atomic_read(&rsp->expedited_need_qs), + sync_rcu_preempt_exp_done(rnp_root), jiffies_stall); if (ret > 0) return; if (ret < 0) { /* Hit a signal, disable CPU stall warnings. */ wait_event(rsp->expedited_wq, - !atomic_read(&rsp->expedited_need_qs)); + sync_rcu_preempt_exp_done(rnp_root)); return; } - pr_err("INFO: %s detected expedited stalls on CPUs: {", + pr_err("INFO: %s detected expedited stalls on CPUs/tasks: {", rsp->name); - for_each_online_cpu(cpu) { - rdp = per_cpu_ptr(rsp->rda, cpu); - - if (rdp->exp_done) - continue; - pr_cont(" %d", cpu); + rcu_for_each_leaf_node(rsp, rnp) { + (void)rcu_print_task_exp_stall(rnp); + mask = 1; + for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask <<= 1) { + struct rcu_data *rdp; + + if (!(rnp->expmask & mask)) + continue; + rdp = per_cpu_ptr(rsp->rda, cpu); + pr_cont(" %d-%c%c%c", cpu, + "O."[cpu_online(cpu)], + "o."[!!(rdp->grpmask & rnp->expmaskinit)], + "N."[!!(rdp->grpmask & rnp->expmaskinitnext)]); + } + mask <<= 1; } pr_cont(" } %lu jiffies s: %lu\n", jiffies - jiffies_start, rsp->expedited_sequence); - for_each_online_cpu(cpu) { - rdp = per_cpu_ptr(rsp->rda, cpu); - - if (rdp->exp_done) - continue; - dump_cpu_task(cpu); + rcu_for_each_leaf_node(rsp, rnp) { + mask = 1; + for (cpu = rnp->grplo; cpu <= rnp->grphi; cpu++, mask <<= 1) { + if (!(rnp->expmask & mask)) + continue; + dump_cpu_task(cpu); + } } jiffies_stall = 3 * rcu_jiffies_till_stall_check() + 3; } @@ -3531,7 +3843,6 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp) */ void synchronize_sched_expedited(void) { - int cpu; unsigned long s; struct rcu_node *rnp; struct rcu_state *rsp = &rcu_sched_state; @@ -3539,48 +3850,16 @@ void synchronize_sched_expedited(void) /* Take a snapshot of the sequence number. */ s = rcu_exp_gp_seq_snap(rsp); - if (!try_get_online_cpus()) { - /* CPU hotplug operation in flight, fall back to normal GP. */ - wait_rcu_gp(call_rcu_sched); - atomic_long_inc(&rsp->expedited_normal); - return; - } - WARN_ON_ONCE(cpu_is_offline(raw_smp_processor_id())); - rnp = exp_funnel_lock(rsp, s); - if (rnp == NULL) { - put_online_cpus(); + if (rnp == NULL) return; /* Someone else did our work for us. */ - } rcu_exp_gp_seq_start(rsp); - - /* Stop each CPU that is online, non-idle, and not us. */ - init_waitqueue_head(&rsp->expedited_wq); - atomic_set(&rsp->expedited_need_qs, 1); /* Extra count avoids race. */ - for_each_online_cpu(cpu) { - struct rcu_data *rdp = per_cpu_ptr(rsp->rda, cpu); - struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu); - - rdp->exp_done = false; - - /* Skip our CPU and any idle CPUs. */ - if (raw_smp_processor_id() == cpu || - !(atomic_add_return(0, &rdtp->dynticks) & 0x1)) - continue; - atomic_inc(&rsp->expedited_need_qs); - stop_one_cpu_nowait(cpu, synchronize_sched_expedited_cpu_stop, - rdp, &rdp->exp_stop_work); - } - - /* Remove extra count and, if necessary, wait for CPUs to stop. */ - if (!atomic_dec_and_test(&rsp->expedited_need_qs)) - synchronize_sched_expedited_wait(rsp); + sync_rcu_exp_select_cpus(rsp, sync_sched_exp_handler); + synchronize_sched_expedited_wait(rsp); rcu_exp_gp_seq_end(rsp); mutex_unlock(&rnp->exp_funnel_mutex); - - put_online_cpus(); } EXPORT_SYMBOL_GPL(synchronize_sched_expedited); @@ -3606,11 +3885,11 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp) /* Is the RCU core waiting for a quiescent state from this CPU? */ if (rcu_scheduler_fully_active && - rdp->qs_pending && !rdp->passed_quiesce && + rdp->core_needs_qs && rdp->cpu_no_qs.b.norm && rdp->rcu_qs_ctr_snap == __this_cpu_read(rcu_qs_ctr)) { - rdp->n_rp_qs_pending++; - } else if (rdp->qs_pending && - (rdp->passed_quiesce || + rdp->n_rp_core_needs_qs++; + } else if (rdp->core_needs_qs && + (!rdp->cpu_no_qs.b.norm || rdp->rcu_qs_ctr_snap != __this_cpu_read(rcu_qs_ctr))) { rdp->n_rp_report_qs++; return 1; @@ -3901,7 +4180,6 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp) /* Set up local state, ensuring consistent view of global state. */ raw_spin_lock_irqsave(&rnp->lock, flags); - rdp->beenonline = 1; /* We have now been online. */ rdp->qlen_last_fqs_check = 0; rdp->n_force_qs_snap = rsp->n_force_qs; rdp->blimit = blimit; @@ -3923,11 +4201,15 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp) raw_spin_lock(&rnp->lock); /* irqs already disabled. */ smp_mb__after_unlock_lock(); rnp->qsmaskinitnext |= mask; + rnp->expmaskinitnext |= mask; + if (!rdp->beenonline) + WRITE_ONCE(rsp->ncpus, READ_ONCE(rsp->ncpus) + 1); + rdp->beenonline = true; /* We have now been online. */ rdp->gpnum = rnp->completed; /* Make CPU later note any new GP. */ rdp->completed = rnp->completed; - rdp->passed_quiesce = false; + rdp->cpu_no_qs.b.norm = true; rdp->rcu_qs_ctr_snap = per_cpu(rcu_qs_ctr, cpu); - rdp->qs_pending = false; + rdp->core_needs_qs = false; trace_rcu_grace_period(rsp->name, rdp->gpnum, TPS("cpuonl")); raw_spin_unlock_irqrestore(&rnp->lock, flags); } @@ -3960,6 +4242,7 @@ int rcu_cpu_notify(struct notifier_block *self, break; case CPU_ONLINE: case CPU_DOWN_FAILED: + sync_sched_exp_online_cleanup(cpu); rcu_boost_kthread_setaffinity(rnp, -1); break; case CPU_DOWN_PREPARE: @@ -3971,6 +4254,12 @@ int rcu_cpu_notify(struct notifier_block *self, rcu_cleanup_dying_cpu(rsp); break; case CPU_DYING_IDLE: + /* QS for any half-done expedited RCU-sched GP. */ + preempt_disable(); + rcu_report_exp_rdp(&rcu_sched_state, + this_cpu_ptr(rcu_sched_state.rda), true); + preempt_enable(); + for_each_rcu_flavor(rsp) { rcu_cleanup_dying_idle_cpu(cpu, rsp); } @@ -4102,7 +4391,6 @@ static void __init rcu_init_one(struct rcu_state *rsp, static const char * const buf[] = RCU_NODE_NAME_INIT; static const char * const fqs[] = RCU_FQS_NAME_INIT; static const char * const exp[] = RCU_EXP_NAME_INIT; - static const char * const exp_sched[] = RCU_EXP_SCHED_NAME_INIT; static u8 fl_mask = 0x1; int levelcnt[RCU_NUM_LVLS]; /* # nodes in each level. */ @@ -4162,18 +4450,13 @@ static void __init rcu_init_one(struct rcu_state *rsp, INIT_LIST_HEAD(&rnp->blkd_tasks); rcu_init_one_nocb(rnp); mutex_init(&rnp->exp_funnel_mutex); - if (rsp == &rcu_sched_state) - lockdep_set_class_and_name( - &rnp->exp_funnel_mutex, - &rcu_exp_sched_class[i], exp_sched[i]); - else - lockdep_set_class_and_name( - &rnp->exp_funnel_mutex, - &rcu_exp_class[i], exp[i]); + lockdep_set_class_and_name(&rnp->exp_funnel_mutex, + &rcu_exp_class[i], exp[i]); } } init_waitqueue_head(&rsp->gp_wq); + init_waitqueue_head(&rsp->expedited_wq); rnp = rsp->level[rcu_num_lvls - 1]; for_each_possible_cpu(i) { while (i > rnp->grphi) @@ -4216,13 +4499,12 @@ static void __init rcu_init_geometry(void) rcu_fanout_leaf, nr_cpu_ids); /* - * The boot-time rcu_fanout_leaf parameter is only permitted - * to increase the leaf-level fanout, not decrease it. Of course, - * the leaf-level fanout cannot exceed the number of bits in - * the rcu_node masks. Complain and fall back to the compile- - * time values if these limits are exceeded. + * The boot-time rcu_fanout_leaf parameter must be at least two + * and cannot exceed the number of bits in the rcu_node masks. + * Complain and fall back to the compile-time values if this + * limit is exceeded. */ - if (rcu_fanout_leaf < RCU_FANOUT_LEAF || + if (rcu_fanout_leaf < 2 || rcu_fanout_leaf > sizeof(unsigned long) * 8) { rcu_fanout_leaf = RCU_FANOUT_LEAF; WARN_ON(1); @@ -4239,10 +4521,13 @@ static void __init rcu_init_geometry(void) /* * The tree must be able to accommodate the configured number of CPUs. - * If this limit is exceeded than we have a serious problem elsewhere. + * If this limit is exceeded, fall back to the compile-time values. */ - if (nr_cpu_ids > rcu_capacity[RCU_NUM_LVLS - 1]) - panic("rcu_init_geometry: rcu_capacity[] is too small"); + if (nr_cpu_ids > rcu_capacity[RCU_NUM_LVLS - 1]) { + rcu_fanout_leaf = RCU_FANOUT_LEAF; + WARN_ON(1); + return; + } /* Calculate the number of levels in the tree. */ for (i = 0; nr_cpu_ids > rcu_capacity[i]; i++) { diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h index 2e991f8361e4..9fb4e238d4dc 100644 --- a/kernel/rcu/tree.h +++ b/kernel/rcu/tree.h @@ -70,8 +70,6 @@ # define RCU_NODE_NAME_INIT { "rcu_node_0" } # define RCU_FQS_NAME_INIT { "rcu_node_fqs_0" } # define RCU_EXP_NAME_INIT { "rcu_node_exp_0" } -# define RCU_EXP_SCHED_NAME_INIT \ - { "rcu_node_exp_sched_0" } #elif NR_CPUS <= RCU_FANOUT_2 # define RCU_NUM_LVLS 2 # define NUM_RCU_LVL_0 1 @@ -81,8 +79,6 @@ # define RCU_NODE_NAME_INIT { "rcu_node_0", "rcu_node_1" } # define RCU_FQS_NAME_INIT { "rcu_node_fqs_0", "rcu_node_fqs_1" } # define RCU_EXP_NAME_INIT { "rcu_node_exp_0", "rcu_node_exp_1" } -# define RCU_EXP_SCHED_NAME_INIT \ - { "rcu_node_exp_sched_0", "rcu_node_exp_sched_1" } #elif NR_CPUS <= RCU_FANOUT_3 # define RCU_NUM_LVLS 3 # define NUM_RCU_LVL_0 1 @@ -93,8 +89,6 @@ # define RCU_NODE_NAME_INIT { "rcu_node_0", "rcu_node_1", "rcu_node_2" } # define RCU_FQS_NAME_INIT { "rcu_node_fqs_0", "rcu_node_fqs_1", "rcu_node_fqs_2" } # define RCU_EXP_NAME_INIT { "rcu_node_exp_0", "rcu_node_exp_1", "rcu_node_exp_2" } -# define RCU_EXP_SCHED_NAME_INIT \ - { "rcu_node_exp_sched_0", "rcu_node_exp_sched_1", "rcu_node_exp_sched_2" } #elif NR_CPUS <= RCU_FANOUT_4 # define RCU_NUM_LVLS 4 # define NUM_RCU_LVL_0 1 @@ -106,8 +100,6 @@ # define RCU_NODE_NAME_INIT { "rcu_node_0", "rcu_node_1", "rcu_node_2", "rcu_node_3" } # define RCU_FQS_NAME_INIT { "rcu_node_fqs_0", "rcu_node_fqs_1", "rcu_node_fqs_2", "rcu_node_fqs_3" } # define RCU_EXP_NAME_INIT { "rcu_node_exp_0", "rcu_node_exp_1", "rcu_node_exp_2", "rcu_node_exp_3" } -# define RCU_EXP_SCHED_NAME_INIT \ - { "rcu_node_exp_sched_0", "rcu_node_exp_sched_1", "rcu_node_exp_sched_2", "rcu_node_exp_sched_3" } #else # error "CONFIG_RCU_FANOUT insufficient for NR_CPUS" #endif /* #if (NR_CPUS) <= RCU_FANOUT_1 */ @@ -171,16 +163,21 @@ struct rcu_node { /* an rcu_data structure, otherwise, each */ /* bit corresponds to a child rcu_node */ /* structure. */ - unsigned long expmask; /* Groups that have ->blkd_tasks */ - /* elements that need to drain to allow the */ - /* current expedited grace period to */ - /* complete (only for PREEMPT_RCU). */ unsigned long qsmaskinit; - /* Per-GP initial value for qsmask & expmask. */ + /* Per-GP initial value for qsmask. */ /* Initialized from ->qsmaskinitnext at the */ /* beginning of each grace period. */ unsigned long qsmaskinitnext; /* Online CPUs for next grace period. */ + unsigned long expmask; /* CPUs or groups that need to check in */ + /* to allow the current expedited GP */ + /* to complete. */ + unsigned long expmaskinit; + /* Per-GP initial values for expmask. */ + /* Initialized from ->expmaskinitnext at the */ + /* beginning of each expedited GP. */ + unsigned long expmaskinitnext; + /* Online CPUs for next expedited GP. */ unsigned long grpmask; /* Mask to apply to parent qsmask. */ /* Only one bit will be set in this mask. */ int grplo; /* lowest-numbered CPU or group here. */ @@ -281,6 +278,18 @@ struct rcu_node { for ((rnp) = (rsp)->level[rcu_num_lvls - 1]; \ (rnp) < &(rsp)->node[rcu_num_nodes]; (rnp)++) +/* + * Union to allow "aggregate OR" operation on the need for a quiescent + * state by the normal and expedited grace periods. + */ +union rcu_noqs { + struct { + u8 norm; + u8 exp; + } b; /* Bits. */ + u16 s; /* Set of bits, aggregate OR here. */ +}; + /* Index values for nxttail array in struct rcu_data. */ #define RCU_DONE_TAIL 0 /* Also RCU_WAIT head. */ #define RCU_WAIT_TAIL 1 /* Also RCU_NEXT_READY head. */ @@ -297,8 +306,8 @@ struct rcu_data { /* is aware of having started. */ unsigned long rcu_qs_ctr_snap;/* Snapshot of rcu_qs_ctr to check */ /* for rcu_all_qs() invocations. */ - bool passed_quiesce; /* User-mode/idle loop etc. */ - bool qs_pending; /* Core waits for quiesc state. */ + union rcu_noqs cpu_no_qs; /* No QSes yet for this CPU. */ + bool core_needs_qs; /* Core waits for quiesc state. */ bool beenonline; /* CPU online at least once. */ bool gpwrap; /* Possible gpnum/completed wrap. */ struct rcu_node *mynode; /* This CPU's leaf of hierarchy */ @@ -307,9 +316,6 @@ struct rcu_data { /* ticks this CPU has handled */ /* during and after the last grace */ /* period it is aware of. */ - struct cpu_stop_work exp_stop_work; - /* Expedited grace-period control */ - /* for CPU stopping. */ /* 2) batch handling */ /* @@ -363,7 +369,7 @@ struct rcu_data { /* 5) __rcu_pending() statistics. */ unsigned long n_rcu_pending; /* rcu_pending() calls since boot. */ - unsigned long n_rp_qs_pending; + unsigned long n_rp_core_needs_qs; unsigned long n_rp_report_qs; unsigned long n_rp_cb_ready; unsigned long n_rp_cpu_needs_gp; @@ -378,7 +384,6 @@ struct rcu_data { struct rcu_head oom_head; #endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */ struct mutex exp_funnel_mutex; - bool exp_done; /* Expedited QS for this CPU? */ /* 7) Callback offloading. */ #ifdef CONFIG_RCU_NOCB_CPU @@ -412,13 +417,6 @@ struct rcu_data { struct rcu_state *rsp; }; -/* Values for fqs_state field in struct rcu_state. */ -#define RCU_GP_IDLE 0 /* No grace period in progress. */ -#define RCU_GP_INIT 1 /* Grace period being initialized. */ -#define RCU_SAVE_DYNTICK 2 /* Need to scan dyntick state. */ -#define RCU_FORCE_QS 3 /* Need to force quiescent state. */ -#define RCU_SIGNAL_INIT RCU_SAVE_DYNTICK - /* Values for nocb_defer_wakeup field in struct rcu_data. */ #define RCU_NOGP_WAKE_NOT 0 #define RCU_NOGP_WAKE 1 @@ -464,14 +462,13 @@ struct rcu_state { /* shut bogus gcc warning) */ u8 flavor_mask; /* bit in flavor mask. */ struct rcu_data __percpu *rda; /* pointer of percu rcu_data. */ - void (*call)(struct rcu_head *head, /* call_rcu() flavor. */ - void (*func)(struct rcu_head *head)); + call_rcu_func_t call; /* call_rcu() flavor. */ + int ncpus; /* # CPUs seen so far. */ /* The following fields are guarded by the root rcu_node's lock. */ - u8 fqs_state ____cacheline_internodealigned_in_smp; - /* Force QS state. */ - u8 boost; /* Subject to priority boost. */ + u8 boost ____cacheline_internodealigned_in_smp; + /* Subject to priority boost. */ unsigned long gpnum; /* Current gp number. */ unsigned long completed; /* # of last completed gp. */ struct task_struct *gp_kthread; /* Task for grace periods. */ @@ -508,6 +505,7 @@ struct rcu_state { atomic_long_t expedited_normal; /* # fallbacks to normal. */ atomic_t expedited_need_qs; /* # CPUs left to check in. */ wait_queue_head_t expedited_wq; /* Wait for check-ins. */ + int ncpus_snap; /* # CPUs seen last time. */ unsigned long jiffies_force_qs; /* Time at which to invoke */ /* force_quiescent_state(). */ @@ -538,8 +536,8 @@ struct rcu_state { #define RCU_GP_FLAG_INIT 0x1 /* Need grace-period initialization. */ #define RCU_GP_FLAG_FQS 0x2 /* Need grace-period quiescent-state forcing. */ -/* Values for rcu_state structure's gp_flags field. */ -#define RCU_GP_WAIT_INIT 0 /* Initial state. */ +/* Values for rcu_state structure's gp_state field. */ +#define RCU_GP_IDLE 0 /* Initial state and no GP in progress. */ #define RCU_GP_WAIT_GPS 1 /* Wait for grace-period start. */ #define RCU_GP_DONE_GPS 2 /* Wait done for grace-period start. */ #define RCU_GP_WAIT_FQS 3 /* Wait for force-quiescent-state time. */ @@ -582,9 +580,10 @@ static bool rcu_preempt_has_tasks(struct rcu_node *rnp); #endif /* #ifdef CONFIG_HOTPLUG_CPU */ static void rcu_print_detail_task_stall(struct rcu_state *rsp); static int rcu_print_task_stall(struct rcu_node *rnp); +static int rcu_print_task_exp_stall(struct rcu_node *rnp); static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp); static void rcu_preempt_check_callbacks(void); -void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu)); +void call_rcu(struct rcu_head *head, rcu_callback_t func); static void __init __rcu_init_preempt(void); static void rcu_initiate_boost(struct rcu_node *rnp, unsigned long flags); static void rcu_preempt_boost_start_gp(struct rcu_node *rnp); diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h index b2bf3963a0ae..630c19772630 100644 --- a/kernel/rcu/tree_plugin.h +++ b/kernel/rcu/tree_plugin.h @@ -101,7 +101,6 @@ RCU_STATE_INITIALIZER(rcu_preempt, 'p', call_rcu); static struct rcu_state *const rcu_state_p = &rcu_preempt_state; static struct rcu_data __percpu *const rcu_data_p = &rcu_preempt_data; -static int rcu_preempted_readers_exp(struct rcu_node *rnp); static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, bool wake); @@ -114,6 +113,147 @@ static void __init rcu_bootup_announce(void) rcu_bootup_announce_oddness(); } +/* Flags for rcu_preempt_ctxt_queue() decision table. */ +#define RCU_GP_TASKS 0x8 +#define RCU_EXP_TASKS 0x4 +#define RCU_GP_BLKD 0x2 +#define RCU_EXP_BLKD 0x1 + +/* + * Queues a task preempted within an RCU-preempt read-side critical + * section into the appropriate location within the ->blkd_tasks list, + * depending on the states of any ongoing normal and expedited grace + * periods. The ->gp_tasks pointer indicates which element the normal + * grace period is waiting on (NULL if none), and the ->exp_tasks pointer + * indicates which element the expedited grace period is waiting on (again, + * NULL if none). If a grace period is waiting on a given element in the + * ->blkd_tasks list, it also waits on all subsequent elements. Thus, + * adding a task to the tail of the list blocks any grace period that is + * already waiting on one of the elements. In contrast, adding a task + * to the head of the list won't block any grace period that is already + * waiting on one of the elements. + * + * This queuing is imprecise, and can sometimes make an ongoing grace + * period wait for a task that is not strictly speaking blocking it. + * Given the choice, we needlessly block a normal grace period rather than + * blocking an expedited grace period. + * + * Note that an endless sequence of expedited grace periods still cannot + * indefinitely postpone a normal grace period. Eventually, all of the + * fixed number of preempted tasks blocking the normal grace period that are + * not also blocking the expedited grace period will resume and complete + * their RCU read-side critical sections. At that point, the ->gp_tasks + * pointer will equal the ->exp_tasks pointer, at which point the end of + * the corresponding expedited grace period will also be the end of the + * normal grace period. + */ +static void rcu_preempt_ctxt_queue(struct rcu_node *rnp, struct rcu_data *rdp, + unsigned long flags) __releases(rnp->lock) +{ + int blkd_state = (rnp->gp_tasks ? RCU_GP_TASKS : 0) + + (rnp->exp_tasks ? RCU_EXP_TASKS : 0) + + (rnp->qsmask & rdp->grpmask ? RCU_GP_BLKD : 0) + + (rnp->expmask & rdp->grpmask ? RCU_EXP_BLKD : 0); + struct task_struct *t = current; + + /* + * Decide where to queue the newly blocked task. In theory, + * this could be an if-statement. In practice, when I tried + * that, it was quite messy. + */ + switch (blkd_state) { + case 0: + case RCU_EXP_TASKS: + case RCU_EXP_TASKS + RCU_GP_BLKD: + case RCU_GP_TASKS: + case RCU_GP_TASKS + RCU_EXP_TASKS: + + /* + * Blocking neither GP, or first task blocking the normal + * GP but not blocking the already-waiting expedited GP. + * Queue at the head of the list to avoid unnecessarily + * blocking the already-waiting GPs. + */ + list_add(&t->rcu_node_entry, &rnp->blkd_tasks); + break; + + case RCU_EXP_BLKD: + case RCU_GP_BLKD: + case RCU_GP_BLKD + RCU_EXP_BLKD: + case RCU_GP_TASKS + RCU_EXP_BLKD: + case RCU_GP_TASKS + RCU_GP_BLKD + RCU_EXP_BLKD: + case RCU_GP_TASKS + RCU_EXP_TASKS + RCU_GP_BLKD + RCU_EXP_BLKD: + + /* + * First task arriving that blocks either GP, or first task + * arriving that blocks the expedited GP (with the normal + * GP already waiting), or a task arriving that blocks + * both GPs with both GPs already waiting. Queue at the + * tail of the list to avoid any GP waiting on any of the + * already queued tasks that are not blocking it. + */ + list_add_tail(&t->rcu_node_entry, &rnp->blkd_tasks); + break; + + case RCU_EXP_TASKS + RCU_EXP_BLKD: + case RCU_EXP_TASKS + RCU_GP_BLKD + RCU_EXP_BLKD: + case RCU_GP_TASKS + RCU_EXP_TASKS + RCU_EXP_BLKD: + + /* + * Second or subsequent task blocking the expedited GP. + * The task either does not block the normal GP, or is the + * first task blocking the normal GP. Queue just after + * the first task blocking the expedited GP. + */ + list_add(&t->rcu_node_entry, rnp->exp_tasks); + break; + + case RCU_GP_TASKS + RCU_GP_BLKD: + case RCU_GP_TASKS + RCU_EXP_TASKS + RCU_GP_BLKD: + + /* + * Second or subsequent task blocking the normal GP. + * The task does not block the expedited GP. Queue just + * after the first task blocking the normal GP. + */ + list_add(&t->rcu_node_entry, rnp->gp_tasks); + break; + + default: + + /* Yet another exercise in excessive paranoia. */ + WARN_ON_ONCE(1); + break; + } + + /* + * We have now queued the task. If it was the first one to + * block either grace period, update the ->gp_tasks and/or + * ->exp_tasks pointers, respectively, to reference the newly + * blocked tasks. + */ + if (!rnp->gp_tasks && (blkd_state & RCU_GP_BLKD)) + rnp->gp_tasks = &t->rcu_node_entry; + if (!rnp->exp_tasks && (blkd_state & RCU_EXP_BLKD)) + rnp->exp_tasks = &t->rcu_node_entry; + raw_spin_unlock(&rnp->lock); + + /* + * Report the quiescent state for the expedited GP. This expedited + * GP should not be able to end until we report, so there should be + * no need to check for a subsequent expedited GP. (Though we are + * still in a quiescent state in any case.) + */ + if (blkd_state & RCU_EXP_BLKD && + t->rcu_read_unlock_special.b.exp_need_qs) { + t->rcu_read_unlock_special.b.exp_need_qs = false; + rcu_report_exp_rdp(rdp->rsp, rdp, true); + } else { + WARN_ON_ONCE(t->rcu_read_unlock_special.b.exp_need_qs); + } + local_irq_restore(flags); +} + /* * Record a preemptible-RCU quiescent state for the specified CPU. Note * that this just means that the task currently running on the CPU is @@ -125,11 +265,11 @@ static void __init rcu_bootup_announce(void) */ static void rcu_preempt_qs(void) { - if (!__this_cpu_read(rcu_data_p->passed_quiesce)) { + if (__this_cpu_read(rcu_data_p->cpu_no_qs.s)) { trace_rcu_grace_period(TPS("rcu_preempt"), __this_cpu_read(rcu_data_p->gpnum), TPS("cpuqs")); - __this_cpu_write(rcu_data_p->passed_quiesce, 1); + __this_cpu_write(rcu_data_p->cpu_no_qs.b.norm, false); barrier(); /* Coordinate with rcu_preempt_check_callbacks(). */ current->rcu_read_unlock_special.b.need_qs = false; } @@ -167,42 +307,18 @@ static void rcu_preempt_note_context_switch(void) t->rcu_blocked_node = rnp; /* - * If this CPU has already checked in, then this task - * will hold up the next grace period rather than the - * current grace period. Queue the task accordingly. - * If the task is queued for the current grace period - * (i.e., this CPU has not yet passed through a quiescent - * state for the current grace period), then as long - * as that task remains queued, the current grace period - * cannot end. Note that there is some uncertainty as - * to exactly when the current grace period started. - * We take a conservative approach, which can result - * in unnecessarily waiting on tasks that started very - * slightly after the current grace period began. C'est - * la vie!!! - * - * But first, note that the current CPU must still be - * on line! + * Verify the CPU's sanity, trace the preemption, and + * then queue the task as required based on the states + * of any ongoing and expedited grace periods. */ WARN_ON_ONCE((rdp->grpmask & rcu_rnp_online_cpus(rnp)) == 0); WARN_ON_ONCE(!list_empty(&t->rcu_node_entry)); - if ((rnp->qsmask & rdp->grpmask) && rnp->gp_tasks != NULL) { - list_add(&t->rcu_node_entry, rnp->gp_tasks->prev); - rnp->gp_tasks = &t->rcu_node_entry; - if (IS_ENABLED(CONFIG_RCU_BOOST) && - rnp->boost_tasks != NULL) - rnp->boost_tasks = rnp->gp_tasks; - } else { - list_add(&t->rcu_node_entry, &rnp->blkd_tasks); - if (rnp->qsmask & rdp->grpmask) - rnp->gp_tasks = &t->rcu_node_entry; - } trace_rcu_preempt_task(rdp->rsp->name, t->pid, (rnp->qsmask & rdp->grpmask) ? rnp->gpnum : rnp->gpnum + 1); - raw_spin_unlock_irqrestore(&rnp->lock, flags); + rcu_preempt_ctxt_queue(rnp, rdp, flags); } else if (t->rcu_read_lock_nesting < 0 && t->rcu_read_unlock_special.s) { @@ -272,6 +388,7 @@ void rcu_read_unlock_special(struct task_struct *t) unsigned long flags; struct list_head *np; bool drop_boost_mutex = false; + struct rcu_data *rdp; struct rcu_node *rnp; union rcu_special special; @@ -282,8 +399,8 @@ void rcu_read_unlock_special(struct task_struct *t) local_irq_save(flags); /* - * If RCU core is waiting for this CPU to exit critical section, - * let it know that we have done so. Because irqs are disabled, + * If RCU core is waiting for this CPU to exit its critical section, + * report the fact that it has exited. Because irqs are disabled, * t->rcu_read_unlock_special cannot change. */ special = t->rcu_read_unlock_special; @@ -296,13 +413,32 @@ void rcu_read_unlock_special(struct task_struct *t) } } + /* + * Respond to a request for an expedited grace period, but only if + * we were not preempted, meaning that we were running on the same + * CPU throughout. If we were preempted, the exp_need_qs flag + * would have been cleared at the time of the first preemption, + * and the quiescent state would be reported when we were dequeued. + */ + if (special.b.exp_need_qs) { + WARN_ON_ONCE(special.b.blocked); + t->rcu_read_unlock_special.b.exp_need_qs = false; + rdp = this_cpu_ptr(rcu_state_p->rda); + rcu_report_exp_rdp(rcu_state_p, rdp, true); + if (!t->rcu_read_unlock_special.s) { + local_irq_restore(flags); + return; + } + } + /* Hardware IRQ handlers cannot block, complain if they get here. */ if (in_irq() || in_serving_softirq()) { lockdep_rcu_suspicious(__FILE__, __LINE__, "rcu_read_unlock() from irq or softirq with blocking in critical section!!!\n"); - pr_alert("->rcu_read_unlock_special: %#x (b: %d, nq: %d)\n", + pr_alert("->rcu_read_unlock_special: %#x (b: %d, enq: %d nq: %d)\n", t->rcu_read_unlock_special.s, t->rcu_read_unlock_special.b.blocked, + t->rcu_read_unlock_special.b.exp_need_qs, t->rcu_read_unlock_special.b.need_qs); local_irq_restore(flags); return; @@ -329,7 +465,7 @@ void rcu_read_unlock_special(struct task_struct *t) raw_spin_unlock(&rnp->lock); /* irqs remain disabled. */ } empty_norm = !rcu_preempt_blocked_readers_cgp(rnp); - empty_exp = !rcu_preempted_readers_exp(rnp); + empty_exp = sync_rcu_preempt_exp_done(rnp); smp_mb(); /* ensure expedited fastpath sees end of RCU c-s. */ np = rcu_next_node_entry(t, rnp); list_del_init(&t->rcu_node_entry); @@ -353,7 +489,7 @@ void rcu_read_unlock_special(struct task_struct *t) * Note that rcu_report_unblock_qs_rnp() releases rnp->lock, * so we must take a snapshot of the expedited state. */ - empty_exp_now = !rcu_preempted_readers_exp(rnp); + empty_exp_now = sync_rcu_preempt_exp_done(rnp); if (!empty_norm && !rcu_preempt_blocked_readers_cgp(rnp)) { trace_rcu_quiescent_state_report(TPS("preempt_rcu"), rnp->gpnum, @@ -450,6 +586,27 @@ static int rcu_print_task_stall(struct rcu_node *rnp) } /* + * Scan the current list of tasks blocked within RCU read-side critical + * sections, printing out the tid of each that is blocking the current + * expedited grace period. + */ +static int rcu_print_task_exp_stall(struct rcu_node *rnp) +{ + struct task_struct *t; + int ndetected = 0; + + if (!rnp->exp_tasks) + return 0; + t = list_entry(rnp->exp_tasks->prev, + struct task_struct, rcu_node_entry); + list_for_each_entry_continue(t, &rnp->blkd_tasks, rcu_node_entry) { + pr_cont(" P%d", t->pid); + ndetected++; + } + return ndetected; +} + +/* * Check that the list of blocked tasks for the newly completed grace * period is in fact empty. It is a serious bug to complete a grace * period that still has RCU readers blocked! This function must be @@ -483,8 +640,8 @@ static void rcu_preempt_check_callbacks(void) return; } if (t->rcu_read_lock_nesting > 0 && - __this_cpu_read(rcu_data_p->qs_pending) && - !__this_cpu_read(rcu_data_p->passed_quiesce)) + __this_cpu_read(rcu_data_p->core_needs_qs) && + __this_cpu_read(rcu_data_p->cpu_no_qs.b.norm)) t->rcu_read_unlock_special.b.need_qs = true; } @@ -500,7 +657,7 @@ static void rcu_preempt_do_callbacks(void) /* * Queue a preemptible-RCU callback for invocation after a grace period. */ -void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu)) +void call_rcu(struct rcu_head *head, rcu_callback_t func) { __call_rcu(head, func, rcu_state_p, -1, 0); } @@ -535,155 +692,41 @@ void synchronize_rcu(void) } EXPORT_SYMBOL_GPL(synchronize_rcu); -static DECLARE_WAIT_QUEUE_HEAD(sync_rcu_preempt_exp_wq); - -/* - * Return non-zero if there are any tasks in RCU read-side critical - * sections blocking the current preemptible-RCU expedited grace period. - * If there is no preemptible-RCU expedited grace period currently in - * progress, returns zero unconditionally. - */ -static int rcu_preempted_readers_exp(struct rcu_node *rnp) -{ - return rnp->exp_tasks != NULL; -} - -/* - * return non-zero if there is no RCU expedited grace period in progress - * for the specified rcu_node structure, in other words, if all CPUs and - * tasks covered by the specified rcu_node structure have done their bit - * for the current expedited grace period. Works only for preemptible - * RCU -- other RCU implementation use other means. - * - * Caller must hold the root rcu_node's exp_funnel_mutex. - */ -static int sync_rcu_preempt_exp_done(struct rcu_node *rnp) -{ - return !rcu_preempted_readers_exp(rnp) && - READ_ONCE(rnp->expmask) == 0; -} - -/* - * Report the exit from RCU read-side critical section for the last task - * that queued itself during or before the current expedited preemptible-RCU - * grace period. This event is reported either to the rcu_node structure on - * which the task was queued or to one of that rcu_node structure's ancestors, - * recursively up the tree. (Calm down, calm down, we do the recursion - * iteratively!) - * - * Caller must hold the root rcu_node's exp_funnel_mutex. - */ -static void rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp, - bool wake) -{ - unsigned long flags; - unsigned long mask; - - raw_spin_lock_irqsave(&rnp->lock, flags); - smp_mb__after_unlock_lock(); - for (;;) { - if (!sync_rcu_preempt_exp_done(rnp)) { - raw_spin_unlock_irqrestore(&rnp->lock, flags); - break; - } - if (rnp->parent == NULL) { - raw_spin_unlock_irqrestore(&rnp->lock, flags); - if (wake) { - smp_mb(); /* EGP done before wake_up(). */ - wake_up(&sync_rcu_preempt_exp_wq); - } - break; - } - mask = rnp->grpmask; - raw_spin_unlock(&rnp->lock); /* irqs remain disabled */ - rnp = rnp->parent; - raw_spin_lock(&rnp->lock); /* irqs already disabled */ - smp_mb__after_unlock_lock(); - rnp->expmask &= ~mask; - } -} - /* - * Snapshot the tasks blocking the newly started preemptible-RCU expedited - * grace period for the specified rcu_node structure, phase 1. If there - * are such tasks, set the ->expmask bits up the rcu_node tree and also - * set the ->expmask bits on the leaf rcu_node structures to tell phase 2 - * that work is needed here. - * - * Caller must hold the root rcu_node's exp_funnel_mutex. + * Remote handler for smp_call_function_single(). If there is an + * RCU read-side critical section in effect, request that the + * next rcu_read_unlock() record the quiescent state up the + * ->expmask fields in the rcu_node tree. Otherwise, immediately + * report the quiescent state. */ -static void -sync_rcu_preempt_exp_init1(struct rcu_state *rsp, struct rcu_node *rnp) +static void sync_rcu_exp_handler(void *info) { - unsigned long flags; - unsigned long mask; - struct rcu_node *rnp_up; - - raw_spin_lock_irqsave(&rnp->lock, flags); - smp_mb__after_unlock_lock(); - WARN_ON_ONCE(rnp->expmask); - WARN_ON_ONCE(rnp->exp_tasks); - if (!rcu_preempt_has_tasks(rnp)) { - /* No blocked tasks, nothing to do. */ - raw_spin_unlock_irqrestore(&rnp->lock, flags); - return; - } - /* Call for Phase 2 and propagate ->expmask bits up the tree. */ - rnp->expmask = 1; - rnp_up = rnp; - while (rnp_up->parent) { - mask = rnp_up->grpmask; - rnp_up = rnp_up->parent; - if (rnp_up->expmask & mask) - break; - raw_spin_lock(&rnp_up->lock); /* irqs already off */ - smp_mb__after_unlock_lock(); - rnp_up->expmask |= mask; - raw_spin_unlock(&rnp_up->lock); /* irqs still off */ - } - raw_spin_unlock_irqrestore(&rnp->lock, flags); -} - -/* - * Snapshot the tasks blocking the newly started preemptible-RCU expedited - * grace period for the specified rcu_node structure, phase 2. If the - * leaf rcu_node structure has its ->expmask field set, check for tasks. - * If there are some, clear ->expmask and set ->exp_tasks accordingly, - * then initiate RCU priority boosting. Otherwise, clear ->expmask and - * invoke rcu_report_exp_rnp() to clear out the upper-level ->expmask bits, - * enabling rcu_read_unlock_special() to do the bit-clearing. - * - * Caller must hold the root rcu_node's exp_funnel_mutex. - */ -static void -sync_rcu_preempt_exp_init2(struct rcu_state *rsp, struct rcu_node *rnp) -{ - unsigned long flags; - - raw_spin_lock_irqsave(&rnp->lock, flags); - smp_mb__after_unlock_lock(); - if (!rnp->expmask) { - /* Phase 1 didn't do anything, so Phase 2 doesn't either. */ - raw_spin_unlock_irqrestore(&rnp->lock, flags); - return; - } - - /* Phase 1 is over. */ - rnp->expmask = 0; + struct rcu_data *rdp; + struct rcu_state *rsp = info; + struct task_struct *t = current; /* - * If there are still blocked tasks, set up ->exp_tasks so that - * rcu_read_unlock_special() will wake us and then boost them. + * Within an RCU read-side critical section, request that the next + * rcu_read_unlock() report. Unless this RCU read-side critical + * section has already blocked, in which case it is already set + * up for the expedited grace period to wait on it. */ - if (rcu_preempt_has_tasks(rnp)) { - rnp->exp_tasks = rnp->blkd_tasks.next; - rcu_initiate_boost(rnp, flags); /* releases rnp->lock */ + if (t->rcu_read_lock_nesting > 0 && + !t->rcu_read_unlock_special.b.blocked) { + t->rcu_read_unlock_special.b.exp_need_qs = true; return; } - /* No longer any blocked tasks, so undo bit setting. */ - raw_spin_unlock_irqrestore(&rnp->lock, flags); - rcu_report_exp_rnp(rsp, rnp, false); + /* + * We are either exiting an RCU read-side critical section (negative + * values of t->rcu_read_lock_nesting) or are not in one at all + * (zero value of t->rcu_read_lock_nesting). Or we are in an RCU + * read-side critical section that blocked before this expedited + * grace period started. Either way, we can immediately report + * the quiescent state. + */ + rdp = this_cpu_ptr(rsp->rda); + rcu_report_exp_rdp(rsp, rdp, true); } /** @@ -713,24 +756,12 @@ void synchronize_rcu_expedited(void) rcu_exp_gp_seq_start(rsp); - /* force all RCU readers onto ->blkd_tasks lists. */ - synchronize_sched_expedited(); - - /* - * Snapshot current state of ->blkd_tasks lists into ->expmask. - * Phase 1 sets bits and phase 2 permits rcu_read_unlock_special() - * to start clearing them. Doing this in one phase leads to - * strange races between setting and clearing bits, so just say "no"! - */ - rcu_for_each_leaf_node(rsp, rnp) - sync_rcu_preempt_exp_init1(rsp, rnp); - rcu_for_each_leaf_node(rsp, rnp) - sync_rcu_preempt_exp_init2(rsp, rnp); + /* Initialize the rcu_node tree in preparation for the wait. */ + sync_rcu_exp_select_cpus(rsp, sync_rcu_exp_handler); /* Wait for snapshotted ->blkd_tasks lists to drain. */ rnp = rcu_get_root(rsp); - wait_event(sync_rcu_preempt_exp_wq, - sync_rcu_preempt_exp_done(rnp)); + synchronize_sched_expedited_wait(rsp); /* Clean up and exit. */ rcu_exp_gp_seq_end(rsp); @@ -835,6 +866,16 @@ static int rcu_print_task_stall(struct rcu_node *rnp) } /* + * Because preemptible RCU does not exist, we never have to check for + * tasks blocked within RCU read-side critical sections that are + * blocking the current expedited grace period. + */ +static int rcu_print_task_exp_stall(struct rcu_node *rnp) +{ + return 0; +} + +/* * Because there is no preemptible RCU, there can be no readers blocked, * so there is no need to check for blocked tasks. So check only for * bogus qsmask values. @@ -1702,8 +1743,12 @@ static void print_cpu_stall_info(struct rcu_state *rsp, int cpu) ticks_value = rsp->gpnum - rdp->gpnum; } print_cpu_stall_fast_no_hz(fast_no_hz, cpu); - pr_err("\t%d: (%lu %s) idle=%03x/%llx/%d softirq=%u/%u fqs=%ld %s\n", - cpu, ticks_value, ticks_title, + pr_err("\t%d-%c%c%c: (%lu %s) idle=%03x/%llx/%d softirq=%u/%u fqs=%ld %s\n", + cpu, + "O."[!!cpu_online(cpu)], + "o."[!!(rdp->grpmask & rdp->mynode->qsmaskinit)], + "N."[!!(rdp->grpmask & rdp->mynode->qsmaskinitnext)], + ticks_value, ticks_title, atomic_read(&rdtp->dynticks) & 0xfff, rdtp->dynticks_nesting, rdtp->dynticks_nmi_nesting, rdp->softirq_snap, kstat_softirqs_cpu(RCU_SOFTIRQ, cpu), diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c index 6fc4c5ff3bb5..ef7093cc9b5c 100644 --- a/kernel/rcu/tree_trace.c +++ b/kernel/rcu/tree_trace.c @@ -117,13 +117,13 @@ static void print_one_rcu_data(struct seq_file *m, struct rcu_data *rdp) if (!rdp->beenonline) return; - seq_printf(m, "%3d%cc=%ld g=%ld pq=%d/%d qp=%d", + seq_printf(m, "%3d%cc=%ld g=%ld cnq=%d/%d:%d", rdp->cpu, cpu_is_offline(rdp->cpu) ? '!' : ' ', ulong2long(rdp->completed), ulong2long(rdp->gpnum), - rdp->passed_quiesce, + rdp->cpu_no_qs.b.norm, rdp->rcu_qs_ctr_snap == per_cpu(rcu_qs_ctr, rdp->cpu), - rdp->qs_pending); + rdp->core_needs_qs); seq_printf(m, " dt=%d/%llx/%d df=%lu", atomic_read(&rdp->dynticks->dynticks), rdp->dynticks->dynticks_nesting, @@ -268,7 +268,7 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp) gpnum = rsp->gpnum; seq_printf(m, "c=%ld g=%ld s=%d jfq=%ld j=%x ", ulong2long(rsp->completed), ulong2long(gpnum), - rsp->fqs_state, + rsp->gp_state, (long)(rsp->jiffies_force_qs - jiffies), (int)(jiffies & 0xffff)); seq_printf(m, "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld/%ld\n", @@ -361,7 +361,7 @@ static void print_one_rcu_pending(struct seq_file *m, struct rcu_data *rdp) cpu_is_offline(rdp->cpu) ? '!' : ' ', rdp->n_rcu_pending); seq_printf(m, "qsp=%ld rpq=%ld cbr=%ld cng=%ld ", - rdp->n_rp_qs_pending, + rdp->n_rp_core_needs_qs, rdp->n_rp_report_qs, rdp->n_rp_cb_ready, rdp->n_rp_cpu_needs_gp); diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 7a0b3bc7c5ed..5f748c5a40f0 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -534,7 +534,7 @@ static void rcu_spawn_tasks_kthread(void); * Post an RCU-tasks callback. First call must be from process context * after the scheduler if fully operational. */ -void call_rcu_tasks(struct rcu_head *rhp, void (*func)(struct rcu_head *rhp)) +void call_rcu_tasks(struct rcu_head *rhp, rcu_callback_t func) { unsigned long flags; bool needwake; diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 2f9c92884817..4d568ac9319e 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -817,7 +817,7 @@ static void set_load_weight(struct task_struct *p) /* * SCHED_IDLE tasks get minimal weight: */ - if (p->policy == SCHED_IDLE) { + if (idle_policy(p->policy)) { load->weight = scale_load(WEIGHT_IDLEPRIO); load->inv_weight = WMULT_IDLEPRIO; return; @@ -827,17 +827,19 @@ static void set_load_weight(struct task_struct *p) load->inv_weight = prio_to_wmult[prio]; } -static void enqueue_task(struct rq *rq, struct task_struct *p, int flags) +static inline void enqueue_task(struct rq *rq, struct task_struct *p, int flags) { update_rq_clock(rq); - sched_info_queued(rq, p); + if (!(flags & ENQUEUE_RESTORE)) + sched_info_queued(rq, p); p->sched_class->enqueue_task(rq, p, flags); } -static void dequeue_task(struct rq *rq, struct task_struct *p, int flags) +static inline void dequeue_task(struct rq *rq, struct task_struct *p, int flags) { update_rq_clock(rq); - sched_info_dequeued(rq, p); + if (!(flags & DEQUEUE_SAVE)) + sched_info_dequeued(rq, p); p->sched_class->dequeue_task(rq, p, flags); } @@ -1178,7 +1180,7 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) * holding rq->lock. */ lockdep_assert_held(&rq->lock); - dequeue_task(rq, p, 0); + dequeue_task(rq, p, DEQUEUE_SAVE); } if (running) put_prev_task(rq, p); @@ -1188,7 +1190,7 @@ void do_set_cpus_allowed(struct task_struct *p, const struct cpumask *new_mask) if (running) p->sched_class->set_curr_task(rq); if (queued) - enqueue_task(rq, p, 0); + enqueue_task(rq, p, ENQUEUE_RESTORE); } /* @@ -1292,7 +1294,7 @@ void set_task_cpu(struct task_struct *p, unsigned int new_cpu) if (task_cpu(p) != new_cpu) { if (p->sched_class->migrate_task_rq) - p->sched_class->migrate_task_rq(p, new_cpu); + p->sched_class->migrate_task_rq(p); p->se.nr_migrations++; perf_event_task_migrate(p); } @@ -1333,12 +1335,16 @@ static int migrate_swap_stop(void *data) struct rq *src_rq, *dst_rq; int ret = -EAGAIN; + if (!cpu_active(arg->src_cpu) || !cpu_active(arg->dst_cpu)) + return -EAGAIN; + src_rq = cpu_rq(arg->src_cpu); dst_rq = cpu_rq(arg->dst_cpu); double_raw_lock(&arg->src_task->pi_lock, &arg->dst_task->pi_lock); double_rq_lock(src_rq, dst_rq); + if (task_cpu(arg->dst_task) != arg->dst_cpu) goto unlock; @@ -1574,13 +1580,15 @@ static int select_fallback_rq(int cpu, struct task_struct *p) goto out; } + /* No more Mr. Nice Guy. */ switch (state) { case cpuset: - /* No more Mr. Nice Guy. */ - cpuset_cpus_allowed_fallback(p); - state = possible; - break; - + if (IS_ENABLED(CONFIG_CPUSETS)) { + cpuset_cpus_allowed_fallback(p); + state = possible; + break; + } + /* fall-through */ case possible: do_set_cpus_allowed(p, cpu_possible_mask); state = fail; @@ -1692,7 +1700,7 @@ ttwu_stat(struct task_struct *p, int cpu, int wake_flags) #endif /* CONFIG_SCHEDSTATS */ } -static void ttwu_activate(struct rq *rq, struct task_struct *p, int en_flags) +static inline void ttwu_activate(struct rq *rq, struct task_struct *p, int en_flags) { activate_task(rq, p, en_flags); p->on_rq = TASK_ON_RQ_QUEUED; @@ -2114,23 +2122,17 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p) #endif /* CONFIG_NUMA_BALANCING */ } +DEFINE_STATIC_KEY_FALSE(sched_numa_balancing); + #ifdef CONFIG_NUMA_BALANCING -#ifdef CONFIG_SCHED_DEBUG + void set_numabalancing_state(bool enabled) { if (enabled) - sched_feat_set("NUMA"); + static_branch_enable(&sched_numa_balancing); else - sched_feat_set("NO_NUMA"); + static_branch_disable(&sched_numa_balancing); } -#else -__read_mostly bool numabalancing_enabled; - -void set_numabalancing_state(bool enabled) -{ - numabalancing_enabled = enabled; -} -#endif /* CONFIG_SCHED_DEBUG */ #ifdef CONFIG_PROC_SYSCTL int sysctl_numa_balancing(struct ctl_table *table, int write, @@ -2138,7 +2140,7 @@ int sysctl_numa_balancing(struct ctl_table *table, int write, { struct ctl_table t; int err; - int state = numabalancing_enabled; + int state = static_branch_likely(&sched_numa_balancing); if (write && !capable(CAP_SYS_ADMIN)) return -EPERM; @@ -2349,6 +2351,8 @@ void wake_up_new_task(struct task_struct *p) struct rq *rq; raw_spin_lock_irqsave(&p->pi_lock, flags); + /* Initialize new task's runnable average */ + init_entity_runnable_average(&p->se); #ifdef CONFIG_SMP /* * Fork balancing, do it here and not earlier because: @@ -2358,16 +2362,21 @@ void wake_up_new_task(struct task_struct *p) set_task_cpu(p, select_task_rq(p, task_cpu(p), SD_BALANCE_FORK, 0)); #endif - /* Initialize new task's runnable average */ - init_entity_runnable_average(&p->se); rq = __task_rq_lock(p); activate_task(rq, p, 0); p->on_rq = TASK_ON_RQ_QUEUED; trace_sched_wakeup_new(p); check_preempt_curr(rq, p, WF_FORK); #ifdef CONFIG_SMP - if (p->sched_class->task_woken) + if (p->sched_class->task_woken) { + /* + * Nothing relies on rq->lock after this, so its fine to + * drop it. + */ + lockdep_unpin_lock(&rq->lock); p->sched_class->task_woken(rq, p); + lockdep_pin_lock(&rq->lock); + } #endif task_rq_unlock(rq, p, &flags); } @@ -2476,7 +2485,6 @@ static inline void prepare_task_switch(struct rq *rq, struct task_struct *prev, struct task_struct *next) { - trace_sched_switch(prev, next); sched_info_switch(rq, prev, next); perf_event_task_sched_out(prev, next); fire_sched_out_preempt_notifiers(prev, next); @@ -2510,6 +2518,22 @@ static struct rq *finish_task_switch(struct task_struct *prev) struct mm_struct *mm = rq->prev_mm; long prev_state; + /* + * The previous task will have left us with a preempt_count of 2 + * because it left us after: + * + * schedule() + * preempt_disable(); // 1 + * __schedule() + * raw_spin_lock_irq(&rq->lock) // 2 + * + * Also, see FORK_PREEMPT_COUNT. + */ + if (WARN_ONCE(preempt_count() != 2*PREEMPT_DISABLE_OFFSET, + "corrupted preempt_count: %s/%d/0x%x\n", + current->comm, current->pid, preempt_count())) + preempt_count_set(FORK_PREEMPT_COUNT); + rq->prev_mm = NULL; /* @@ -2517,11 +2541,11 @@ static struct rq *finish_task_switch(struct task_struct *prev) * If a task dies, then it sets TASK_DEAD in tsk->state and calls * schedule one last time. The schedule call will never return, and * the scheduled task must drop that reference. - * The test for TASK_DEAD must occur while the runqueue locks are - * still held, otherwise prev could be scheduled on another cpu, die - * there before we look at prev->state, and then the reference would - * be dropped twice. - * Manfred Spraul <manfred@colorfullife.com> + * + * We must observe prev->state before clearing prev->on_cpu (in + * finish_lock_switch), otherwise a concurrent wakeup can get prev + * running on another CPU and we could rave with its RUNNING -> DEAD + * transition, resulting in a double drop. */ prev_state = prev->state; vtime_task_switch(prev); @@ -2594,8 +2618,15 @@ asmlinkage __visible void schedule_tail(struct task_struct *prev) { struct rq *rq; - /* finish_task_switch() drops rq->lock and enables preemtion */ - preempt_disable(); + /* + * New tasks start with FORK_PREEMPT_COUNT, see there and + * finish_task_switch() for details. + * + * finish_task_switch() will drop rq->lock() and lower preempt_count + * and the preempt_enable() will end up enabling preemption (on + * PREEMPT_COUNT kernels). + */ + rq = finish_task_switch(prev); balance_callback(rq); preempt_enable(); @@ -2953,15 +2984,13 @@ static noinline void __schedule_bug(struct task_struct *prev) static inline void schedule_debug(struct task_struct *prev) { #ifdef CONFIG_SCHED_STACK_END_CHECK - BUG_ON(unlikely(task_stack_end_corrupted(prev))); + BUG_ON(task_stack_end_corrupted(prev)); #endif - /* - * Test if we are atomic. Since do_exit() needs to call into - * schedule() atomically, we ignore that path. Otherwise whine - * if we are scheduling when we should not. - */ - if (unlikely(in_atomic_preempt_off() && prev->state != TASK_DEAD)) + + if (unlikely(in_atomic_preempt_off())) { __schedule_bug(prev); + preempt_count_set(PREEMPT_DISABLED); + } rcu_sleep_check(); profile_hit(SCHED_PROFILING, __builtin_return_address(0)); @@ -3047,7 +3076,7 @@ again: * * WARNING: must be called with preemption disabled! */ -static void __sched __schedule(void) +static void __sched notrace __schedule(bool preempt) { struct task_struct *prev, *next; unsigned long *switch_count; @@ -3059,6 +3088,17 @@ static void __sched __schedule(void) rcu_note_context_switch(); prev = rq->curr; + /* + * do_exit() calls schedule() with preemption disabled as an exception; + * however we must fix that up, otherwise the next task will see an + * inconsistent (higher) preempt count. + * + * It also avoids the below schedule_debug() test from complaining + * about this. + */ + if (unlikely(prev->state == TASK_DEAD)) + preempt_enable_no_resched_notrace(); + schedule_debug(prev); if (sched_feat(HRTICK)) @@ -3076,7 +3116,7 @@ static void __sched __schedule(void) rq->clock_skip_update <<= 1; /* promote REQ to ACT */ switch_count = &prev->nivcsw; - if (prev->state && !(preempt_count() & PREEMPT_ACTIVE)) { + if (!preempt && prev->state) { if (unlikely(signal_pending_state(prev->state, prev))) { prev->state = TASK_RUNNING; } else { @@ -3112,6 +3152,7 @@ static void __sched __schedule(void) rq->curr = next; ++*switch_count; + trace_sched_switch(preempt, prev, next); rq = context_switch(rq, prev, next); /* unlocks the rq */ cpu = cpu_of(rq); } else { @@ -3141,7 +3182,7 @@ asmlinkage __visible void __sched schedule(void) sched_submit_work(tsk); do { preempt_disable(); - __schedule(); + __schedule(false); sched_preempt_enable_no_resched(); } while (need_resched()); } @@ -3181,9 +3222,9 @@ void __sched schedule_preempt_disabled(void) static void __sched notrace preempt_schedule_common(void) { do { - preempt_active_enter(); - __schedule(); - preempt_active_exit(); + preempt_disable_notrace(); + __schedule(true); + preempt_enable_no_resched_notrace(); /* * Check again in case we missed a preemption opportunity @@ -3234,24 +3275,17 @@ asmlinkage __visible void __sched notrace preempt_schedule_notrace(void) return; do { - /* - * Use raw __prempt_count() ops that don't call function. - * We can't call functions before disabling preemption which - * disarm preemption tracing recursions. - */ - __preempt_count_add(PREEMPT_ACTIVE + PREEMPT_DISABLE_OFFSET); - barrier(); + preempt_disable_notrace(); /* * Needs preempt disabled in case user_exit() is traced * and the tracer calls preempt_enable_notrace() causing * an infinite recursion. */ prev_ctx = exception_enter(); - __schedule(); + __schedule(true); exception_exit(prev_ctx); - barrier(); - __preempt_count_sub(PREEMPT_ACTIVE + PREEMPT_DISABLE_OFFSET); + preempt_enable_no_resched_notrace(); } while (need_resched()); } EXPORT_SYMBOL_GPL(preempt_schedule_notrace); @@ -3274,11 +3308,11 @@ asmlinkage __visible void __sched preempt_schedule_irq(void) prev_state = exception_enter(); do { - preempt_active_enter(); + preempt_disable(); local_irq_enable(); - __schedule(); + __schedule(true); local_irq_disable(); - preempt_active_exit(); + sched_preempt_enable_no_resched(); } while (need_resched()); exception_exit(prev_state); @@ -3306,7 +3340,7 @@ EXPORT_SYMBOL(default_wake_function); */ void rt_mutex_setprio(struct task_struct *p, int prio) { - int oldprio, queued, running, enqueue_flag = 0; + int oldprio, queued, running, enqueue_flag = ENQUEUE_RESTORE; struct rq *rq; const struct sched_class *prev_class; @@ -3338,7 +3372,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio) queued = task_on_rq_queued(p); running = task_current(rq, p); if (queued) - dequeue_task(rq, p, 0); + dequeue_task(rq, p, DEQUEUE_SAVE); if (running) put_prev_task(rq, p); @@ -3356,7 +3390,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio) if (!dl_prio(p->normal_prio) || (pi_task && dl_entity_preempt(&pi_task->dl, &p->dl))) { p->dl.dl_boosted = 1; - enqueue_flag = ENQUEUE_REPLENISH; + enqueue_flag |= ENQUEUE_REPLENISH; } else p->dl.dl_boosted = 0; p->sched_class = &dl_sched_class; @@ -3364,7 +3398,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio) if (dl_prio(oldprio)) p->dl.dl_boosted = 0; if (oldprio < prio) - enqueue_flag = ENQUEUE_HEAD; + enqueue_flag |= ENQUEUE_HEAD; p->sched_class = &rt_sched_class; } else { if (dl_prio(oldprio)) @@ -3416,7 +3450,7 @@ void set_user_nice(struct task_struct *p, long nice) } queued = task_on_rq_queued(p); if (queued) - dequeue_task(rq, p, 0); + dequeue_task(rq, p, DEQUEUE_SAVE); p->static_prio = NICE_TO_PRIO(nice); set_load_weight(p); @@ -3425,7 +3459,7 @@ void set_user_nice(struct task_struct *p, long nice) delta = p->prio - old_prio; if (queued) { - enqueue_task(rq, p, 0); + enqueue_task(rq, p, ENQUEUE_RESTORE); /* * If the task increased its priority or is running and * lowered its priority, then reschedule its CPU: @@ -3746,10 +3780,7 @@ recheck: } else { reset_on_fork = !!(attr->sched_flags & SCHED_FLAG_RESET_ON_FORK); - if (policy != SCHED_DEADLINE && - policy != SCHED_FIFO && policy != SCHED_RR && - policy != SCHED_NORMAL && policy != SCHED_BATCH && - policy != SCHED_IDLE) + if (!valid_policy(policy)) return -EINVAL; } @@ -3805,7 +3836,7 @@ recheck: * Treat SCHED_IDLE as nice 20. Only allow a switch to * SCHED_NORMAL if the RLIMIT_NICE would normally permit it. */ - if (p->policy == SCHED_IDLE && policy != SCHED_IDLE) { + if (idle_policy(p->policy) && !idle_policy(policy)) { if (!can_nice(p, task_nice(p))) return -EPERM; } @@ -3930,7 +3961,7 @@ change: queued = task_on_rq_queued(p); running = task_current(rq, p); if (queued) - dequeue_task(rq, p, 0); + dequeue_task(rq, p, DEQUEUE_SAVE); if (running) put_prev_task(rq, p); @@ -3940,11 +3971,15 @@ change: if (running) p->sched_class->set_curr_task(rq); if (queued) { + int enqueue_flags = ENQUEUE_RESTORE; /* * We enqueue to tail when the priority of a task is * increased (user space view). */ - enqueue_task(rq, p, oldprio <= p->prio ? ENQUEUE_HEAD : 0); + if (oldprio <= p->prio) + enqueue_flags |= ENQUEUE_HEAD; + + enqueue_task(rq, p, enqueue_flags); } check_class_changed(rq, p, prev_class, oldprio); @@ -4022,6 +4057,7 @@ int sched_setscheduler_nocheck(struct task_struct *p, int policy, { return _sched_setscheduler(p, policy, param, false); } +EXPORT_SYMBOL_GPL(sched_setscheduler_nocheck); static int do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param) @@ -4934,7 +4970,15 @@ void init_idle(struct task_struct *idle, int cpu) idle->state = TASK_RUNNING; idle->se.exec_start = sched_clock(); - do_set_cpus_allowed(idle, cpumask_of(cpu)); +#ifdef CONFIG_SMP + /* + * Its possible that init_idle() gets called multiple times on a task, + * in that case do_set_cpus_allowed() will not do the right thing. + * + * And since this is boot we can forgo the serialization. + */ + set_cpus_allowed_common(idle, cpumask_of(cpu)); +#endif /* * We're having a chicken and egg problem, even though we are * holding rq->lock, the cpu isn't yet set to this cpu so the @@ -4951,7 +4995,7 @@ void init_idle(struct task_struct *idle, int cpu) rq->curr = rq->idle = idle; idle->on_rq = TASK_ON_RQ_QUEUED; -#if defined(CONFIG_SMP) +#ifdef CONFIG_SMP idle->on_cpu = 1; #endif raw_spin_unlock(&rq->lock); @@ -4966,7 +5010,7 @@ void init_idle(struct task_struct *idle, int cpu) idle->sched_class = &idle_sched_class; ftrace_graph_init_idle_task(idle, cpu); vtime_init_idle(idle, cpu); -#if defined(CONFIG_SMP) +#ifdef CONFIG_SMP sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu); #endif } @@ -5085,7 +5129,7 @@ void sched_setnuma(struct task_struct *p, int nid) running = task_current(rq, p); if (queued) - dequeue_task(rq, p, 0); + dequeue_task(rq, p, DEQUEUE_SAVE); if (running) put_prev_task(rq, p); @@ -5094,7 +5138,7 @@ void sched_setnuma(struct task_struct *p, int nid) if (running) p->sched_class->set_curr_task(rq); if (queued) - enqueue_task(rq, p, 0); + enqueue_task(rq, p, ENQUEUE_RESTORE); task_rq_unlock(rq, p, &flags); } #endif /* CONFIG_NUMA_BALANCING */ @@ -5515,21 +5559,27 @@ static void set_cpu_rq_start_time(void) static int sched_cpu_active(struct notifier_block *nfb, unsigned long action, void *hcpu) { + int cpu = (long)hcpu; + switch (action & ~CPU_TASKS_FROZEN) { case CPU_STARTING: set_cpu_rq_start_time(); return NOTIFY_OK; + case CPU_ONLINE: /* * At this point a starting CPU has marked itself as online via * set_cpu_online(). But it might not yet have marked itself * as active, which is essential from here on. - * - * Thus, fall-through and help the starting CPU along. */ + set_cpu_active(cpu, true); + stop_machine_unpark(cpu); + return NOTIFY_OK; + case CPU_DOWN_FAILED: - set_cpu_active((long)hcpu, true); + set_cpu_active(cpu, true); return NOTIFY_OK; + default: return NOTIFY_DONE; } @@ -6461,7 +6511,8 @@ static struct sched_domain_topology_level default_topology[] = { { NULL, }, }; -struct sched_domain_topology_level *sched_domain_topology = default_topology; +static struct sched_domain_topology_level *sched_domain_topology = + default_topology; #define for_each_sd_topology(tl) \ for (tl = sched_domain_topology; tl->mask; tl++) @@ -7230,9 +7281,6 @@ void __init sched_init_smp(void) alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL); alloc_cpumask_var(&fallback_doms, GFP_KERNEL); - /* nohz_full won't take effect without isolating the cpus. */ - tick_nohz_full_add_cpus_to(cpu_isolated_map); - sched_init_numa(); /* @@ -7465,7 +7513,7 @@ void __init sched_init(void) #ifdef CONFIG_DEBUG_ATOMIC_SLEEP static inline int preempt_count_equals(int preempt_offset) { - int nested = (preempt_count() & ~PREEMPT_ACTIVE) + rcu_preempt_depth(); + int nested = preempt_count() + rcu_preempt_depth(); return (nested == preempt_offset); } @@ -7712,7 +7760,7 @@ void sched_move_task(struct task_struct *tsk) queued = task_on_rq_queued(tsk); if (queued) - dequeue_task(rq, tsk, 0); + dequeue_task(rq, tsk, DEQUEUE_SAVE); if (unlikely(running)) put_prev_task(rq, tsk); @@ -7728,7 +7776,7 @@ void sched_move_task(struct task_struct *tsk) #ifdef CONFIG_FAIR_GROUP_SCHED if (tsk->sched_class->task_move_group) - tsk->sched_class->task_move_group(tsk, queued); + tsk->sched_class->task_move_group(tsk); else #endif set_task_rq(tsk, task_cpu(tsk)); @@ -7736,7 +7784,7 @@ void sched_move_task(struct task_struct *tsk) if (unlikely(running)) tsk->sched_class->set_curr_task(rq); if (queued) - enqueue_task(rq, tsk, 0); + enqueue_task(rq, tsk, ENQUEUE_RESTORE); task_rq_unlock(rq, tsk, &flags); } @@ -8196,21 +8244,6 @@ static void cpu_cgroup_attach(struct cgroup_subsys_state *css, sched_move_task(task); } -static void cpu_cgroup_exit(struct cgroup_subsys_state *css, - struct cgroup_subsys_state *old_css, - struct task_struct *task) -{ - /* - * cgroup_exit() is called in the copy_process() failure path. - * Ignore this case since the task hasn't ran yet, this avoids - * trying to poke a half freed task state from generic code. - */ - if (!(task->flags & PF_EXITING)) - return; - - sched_move_task(task); -} - #ifdef CONFIG_FAIR_GROUP_SCHED static int cpu_shares_write_u64(struct cgroup_subsys_state *css, struct cftype *cftype, u64 shareval) @@ -8542,7 +8575,6 @@ struct cgroup_subsys cpu_cgrp_subsys = { .fork = cpu_cgroup_fork, .can_attach = cpu_cgroup_can_attach, .attach = cpu_cgroup_attach, - .exit = cpu_cgroup_exit, .legacy_cftypes = cpu_files, .early_init = 1, }; diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c index c6acb07466bb..5a75b08cfd85 100644 --- a/kernel/sched/cpudeadline.c +++ b/kernel/sched/cpudeadline.c @@ -31,11 +31,6 @@ static inline int right_child(int i) return (i << 1) + 2; } -static inline int dl_time_before(u64 a, u64 b) -{ - return (s64)(a - b) < 0; -} - static void cpudl_exchange(struct cpudl *cp, int a, int b) { int cpu_a = cp->elements[a].cpu, cpu_b = cp->elements[b].cpu; diff --git a/kernel/sched/cpudeadline.h b/kernel/sched/cpudeadline.h index 1a0a6ef2fbe1..fcbdf83fed7e 100644 --- a/kernel/sched/cpudeadline.h +++ b/kernel/sched/cpudeadline.h @@ -2,6 +2,7 @@ #define _LINUX_CPUDL_H #include <linux/sched.h> +#include <linux/sched/deadline.h> #define IDX_INVALID -1 diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index fc8f01083527..8b0a15e285f9 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -668,8 +668,15 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer) * Queueing this task back might have overloaded rq, check if we need * to kick someone away. */ - if (has_pushable_dl_tasks(rq)) + if (has_pushable_dl_tasks(rq)) { + /* + * Nothing relies on rq->lock after this, so its safe to drop + * rq->lock. + */ + lockdep_unpin_lock(&rq->lock); push_dl_task(rq); + lockdep_pin_lock(&rq->lock); + } #endif unlock: @@ -1066,8 +1073,9 @@ select_task_rq_dl(struct task_struct *p, int cpu, int sd_flag, int flags) int target = find_later_rq(p); if (target != -1 && - dl_time_before(p->dl.deadline, - cpu_rq(target)->dl.earliest_dl.curr)) + (dl_time_before(p->dl.deadline, + cpu_rq(target)->dl.earliest_dl.curr) || + (cpu_rq(target)->dl.dl_nr_running == 0))) cpu = target; } rcu_read_unlock(); @@ -1417,7 +1425,8 @@ static struct rq *find_lock_later_rq(struct task_struct *task, struct rq *rq) later_rq = cpu_rq(cpu); - if (!dl_time_before(task->dl.deadline, + if (later_rq->dl.dl_nr_running && + !dl_time_before(task->dl.deadline, later_rq->dl.earliest_dl.curr)) { /* * Target rq has tasks of equal or earlier deadline, diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 6e2e3483b1ec..824aa9f501a3 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -661,11 +661,12 @@ static unsigned long task_h_load(struct task_struct *p); /* * We choose a half-life close to 1 scheduling period. - * Note: The tables below are dependent on this value. + * Note: The tables runnable_avg_yN_inv and runnable_avg_yN_sum are + * dependent on this value. */ #define LOAD_AVG_PERIOD 32 #define LOAD_AVG_MAX 47742 /* maximum possible load avg */ -#define LOAD_AVG_MAX_N 345 /* number of full periods to produce LOAD_MAX_AVG */ +#define LOAD_AVG_MAX_N 345 /* number of full periods to produce LOAD_AVG_MAX */ /* Give new sched_entity start runnable values to heavy its load in infant time */ void init_entity_runnable_average(struct sched_entity *se) @@ -682,7 +683,7 @@ void init_entity_runnable_average(struct sched_entity *se) sa->load_avg = scale_load_down(se->load.weight); sa->load_sum = sa->load_avg * LOAD_AVG_MAX; sa->util_avg = scale_load_down(SCHED_LOAD_SCALE); - sa->util_sum = LOAD_AVG_MAX; + sa->util_sum = sa->util_avg * LOAD_AVG_MAX; /* when this task enqueue'ed, it will contribute to its cfs_rq's load_avg */ } @@ -2069,7 +2070,7 @@ void task_numa_fault(int last_cpupid, int mem_node, int pages, int flags) int local = !!(flags & TNF_FAULT_LOCAL); int priv; - if (!numabalancing_enabled) + if (!static_branch_likely(&sched_numa_balancing)) return; /* for example, ksmd faulting in a user's mm */ @@ -2157,7 +2158,7 @@ void task_numa_work(struct callback_head *work) struct vm_area_struct *vma; unsigned long start, end; unsigned long nr_pte_updates = 0; - long pages; + long pages, virtpages; WARN_ON_ONCE(p != container_of(work, struct task_struct, numa_work)); @@ -2203,9 +2204,11 @@ void task_numa_work(struct callback_head *work) start = mm->numa_scan_offset; pages = sysctl_numa_balancing_scan_size; pages <<= 20 - PAGE_SHIFT; /* MB in pages */ + virtpages = pages * 8; /* Scan up to this much virtual space */ if (!pages) return; + down_read(&mm->mmap_sem); vma = find_vma(mm, start); if (!vma) { @@ -2240,18 +2243,22 @@ void task_numa_work(struct callback_head *work) start = max(start, vma->vm_start); end = ALIGN(start + (pages << PAGE_SHIFT), HPAGE_SIZE); end = min(end, vma->vm_end); - nr_pte_updates += change_prot_numa(vma, start, end); + nr_pte_updates = change_prot_numa(vma, start, end); /* - * Scan sysctl_numa_balancing_scan_size but ensure that - * at least one PTE is updated so that unused virtual - * address space is quickly skipped. + * Try to scan sysctl_numa_balancing_size worth of + * hpages that have at least one present PTE that + * is not already pte-numa. If the VMA contains + * areas that are unused or already full of prot_numa + * PTEs, scan up to virtpages, to skip through those + * areas faster. */ if (nr_pte_updates) pages -= (end - start) >> PAGE_SHIFT; + virtpages -= (end - start) >> PAGE_SHIFT; start = end; - if (pages <= 0) + if (pages <= 0 || virtpages <= 0) goto out; cond_resched(); @@ -2363,7 +2370,7 @@ static inline long calc_tg_weight(struct task_group *tg, struct cfs_rq *cfs_rq) */ tg_weight = atomic_long_read(&tg->load_avg); tg_weight -= cfs_rq->tg_load_avg_contrib; - tg_weight += cfs_rq_load_avg(cfs_rq); + tg_weight += cfs_rq->load.weight; return tg_weight; } @@ -2373,7 +2380,7 @@ static long calc_cfs_shares(struct cfs_rq *cfs_rq, struct task_group *tg) long tg_weight, load, shares; tg_weight = calc_tg_weight(tg, cfs_rq); - load = cfs_rq_load_avg(cfs_rq); + load = cfs_rq->load.weight; shares = (tg->shares * load); if (tg_weight) @@ -2515,6 +2522,12 @@ static u32 __compute_runnable_contrib(u64 n) return contrib + runnable_avg_yN_sum[n]; } +#if (SCHED_LOAD_SHIFT - SCHED_LOAD_RESOLUTION) != 10 || SCHED_CAPACITY_SHIFT != 10 +#error "load tracking assumes 2^10 as unit" +#endif + +#define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT) + /* * We can represent the historical contribution to runnable average as the * coefficients of a geometric series. To do this we sub-divide our runnable @@ -2547,10 +2560,10 @@ static __always_inline int __update_load_avg(u64 now, int cpu, struct sched_avg *sa, unsigned long weight, int running, struct cfs_rq *cfs_rq) { - u64 delta, periods; + u64 delta, scaled_delta, periods; u32 contrib; - int delta_w, decayed = 0; - unsigned long scale_freq = arch_scale_freq_capacity(NULL, cpu); + unsigned int delta_w, scaled_delta_w, decayed = 0; + unsigned long scale_freq, scale_cpu; delta = now - sa->last_update_time; /* @@ -2571,6 +2584,9 @@ __update_load_avg(u64 now, int cpu, struct sched_avg *sa, return 0; sa->last_update_time = now; + scale_freq = arch_scale_freq_capacity(NULL, cpu); + scale_cpu = arch_scale_cpu_capacity(NULL, cpu); + /* delta_w is the amount already accumulated against our next period */ delta_w = sa->period_contrib; if (delta + delta_w >= 1024) { @@ -2585,13 +2601,16 @@ __update_load_avg(u64 now, int cpu, struct sched_avg *sa, * period and accrue it. */ delta_w = 1024 - delta_w; + scaled_delta_w = cap_scale(delta_w, scale_freq); if (weight) { - sa->load_sum += weight * delta_w; - if (cfs_rq) - cfs_rq->runnable_load_sum += weight * delta_w; + sa->load_sum += weight * scaled_delta_w; + if (cfs_rq) { + cfs_rq->runnable_load_sum += + weight * scaled_delta_w; + } } if (running) - sa->util_sum += delta_w * scale_freq >> SCHED_CAPACITY_SHIFT; + sa->util_sum += scaled_delta_w * scale_cpu; delta -= delta_w; @@ -2608,23 +2627,25 @@ __update_load_avg(u64 now, int cpu, struct sched_avg *sa, /* Efficiently calculate \sum (1..n_period) 1024*y^i */ contrib = __compute_runnable_contrib(periods); + contrib = cap_scale(contrib, scale_freq); if (weight) { sa->load_sum += weight * contrib; if (cfs_rq) cfs_rq->runnable_load_sum += weight * contrib; } if (running) - sa->util_sum += contrib * scale_freq >> SCHED_CAPACITY_SHIFT; + sa->util_sum += contrib * scale_cpu; } /* Remainder of delta accrued against u_0` */ + scaled_delta = cap_scale(delta, scale_freq); if (weight) { - sa->load_sum += weight * delta; + sa->load_sum += weight * scaled_delta; if (cfs_rq) - cfs_rq->runnable_load_sum += weight * delta; + cfs_rq->runnable_load_sum += weight * scaled_delta; } if (running) - sa->util_sum += delta * scale_freq >> SCHED_CAPACITY_SHIFT; + sa->util_sum += scaled_delta * scale_cpu; sa->period_contrib += delta; @@ -2634,7 +2655,7 @@ __update_load_avg(u64 now, int cpu, struct sched_avg *sa, cfs_rq->runnable_load_avg = div_u64(cfs_rq->runnable_load_sum, LOAD_AVG_MAX); } - sa->util_avg = (sa->util_sum << SCHED_LOAD_SHIFT) / LOAD_AVG_MAX; + sa->util_avg = sa->util_sum / LOAD_AVG_MAX; } return decayed; @@ -2664,20 +2685,20 @@ static inline u64 cfs_rq_clock_task(struct cfs_rq *cfs_rq); /* Group cfs_rq's load_avg is used for task_h_load and update_cfs_share */ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) { - int decayed; struct sched_avg *sa = &cfs_rq->avg; + int decayed, removed = 0; if (atomic_long_read(&cfs_rq->removed_load_avg)) { long r = atomic_long_xchg(&cfs_rq->removed_load_avg, 0); sa->load_avg = max_t(long, sa->load_avg - r, 0); sa->load_sum = max_t(s64, sa->load_sum - r * LOAD_AVG_MAX, 0); + removed = 1; } if (atomic_long_read(&cfs_rq->removed_util_avg)) { long r = atomic_long_xchg(&cfs_rq->removed_util_avg, 0); sa->util_avg = max_t(long, sa->util_avg - r, 0); - sa->util_sum = max_t(s32, sa->util_sum - - ((r * LOAD_AVG_MAX) >> SCHED_LOAD_SHIFT), 0); + sa->util_sum = max_t(s32, sa->util_sum - r * LOAD_AVG_MAX, 0); } decayed = __update_load_avg(now, cpu_of(rq_of(cfs_rq)), sa, @@ -2688,40 +2709,77 @@ static inline int update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq) cfs_rq->load_last_update_time_copy = sa->last_update_time; #endif - return decayed; + return decayed || removed; } /* Update task and its cfs_rq load average */ static inline void update_load_avg(struct sched_entity *se, int update_tg) { struct cfs_rq *cfs_rq = cfs_rq_of(se); - int cpu = cpu_of(rq_of(cfs_rq)); u64 now = cfs_rq_clock_task(cfs_rq); + int cpu = cpu_of(rq_of(cfs_rq)); /* * Track task load average for carrying it to new CPU after migrated, and * track group sched_entity load average for task_h_load calc in migration */ __update_load_avg(now, cpu, &se->avg, - se->on_rq * scale_load_down(se->load.weight), cfs_rq->curr == se, NULL); + se->on_rq * scale_load_down(se->load.weight), + cfs_rq->curr == se, NULL); if (update_cfs_rq_load_avg(now, cfs_rq) && update_tg) update_tg_load_avg(cfs_rq, 0); } +static void attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + if (!sched_feat(ATTACH_AGE_LOAD)) + goto skip_aging; + + /* + * If we got migrated (either between CPUs or between cgroups) we'll + * have aged the average right before clearing @last_update_time. + */ + if (se->avg.last_update_time) { + __update_load_avg(cfs_rq->avg.last_update_time, cpu_of(rq_of(cfs_rq)), + &se->avg, 0, 0, NULL); + + /* + * XXX: we could have just aged the entire load away if we've been + * absent from the fair class for too long. + */ + } + +skip_aging: + se->avg.last_update_time = cfs_rq->avg.last_update_time; + cfs_rq->avg.load_avg += se->avg.load_avg; + cfs_rq->avg.load_sum += se->avg.load_sum; + cfs_rq->avg.util_avg += se->avg.util_avg; + cfs_rq->avg.util_sum += se->avg.util_sum; +} + +static void detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) +{ + __update_load_avg(cfs_rq->avg.last_update_time, cpu_of(rq_of(cfs_rq)), + &se->avg, se->on_rq * scale_load_down(se->load.weight), + cfs_rq->curr == se, NULL); + + cfs_rq->avg.load_avg = max_t(long, cfs_rq->avg.load_avg - se->avg.load_avg, 0); + cfs_rq->avg.load_sum = max_t(s64, cfs_rq->avg.load_sum - se->avg.load_sum, 0); + cfs_rq->avg.util_avg = max_t(long, cfs_rq->avg.util_avg - se->avg.util_avg, 0); + cfs_rq->avg.util_sum = max_t(s32, cfs_rq->avg.util_sum - se->avg.util_sum, 0); +} + /* Add the load generated by se into cfs_rq's load average */ static inline void enqueue_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) { struct sched_avg *sa = &se->avg; u64 now = cfs_rq_clock_task(cfs_rq); - int migrated = 0, decayed; + int migrated, decayed; - if (sa->last_update_time == 0) { - sa->last_update_time = now; - migrated = 1; - } - else { + migrated = !sa->last_update_time; + if (!migrated) { __update_load_avg(now, cpu_of(rq_of(cfs_rq)), sa, se->on_rq * scale_load_down(se->load.weight), cfs_rq->curr == se, NULL); @@ -2732,12 +2790,8 @@ enqueue_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) cfs_rq->runnable_load_avg += sa->load_avg; cfs_rq->runnable_load_sum += sa->load_sum; - if (migrated) { - cfs_rq->avg.load_avg += sa->load_avg; - cfs_rq->avg.load_sum += sa->load_sum; - cfs_rq->avg.util_avg += sa->util_avg; - cfs_rq->avg.util_sum += sa->util_sum; - } + if (migrated) + attach_entity_load_avg(cfs_rq, se); if (decayed || migrated) update_tg_load_avg(cfs_rq, 0); @@ -2752,7 +2806,7 @@ dequeue_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) cfs_rq->runnable_load_avg = max_t(long, cfs_rq->runnable_load_avg - se->avg.load_avg, 0); cfs_rq->runnable_load_sum = - max_t(s64, cfs_rq->runnable_load_sum - se->avg.load_sum, 0); + max_t(s64, cfs_rq->runnable_load_sum - se->avg.load_sum, 0); } /* @@ -2820,6 +2874,11 @@ static inline void dequeue_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) {} static inline void remove_entity_load_avg(struct sched_entity *se) {} +static inline void +attach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) {} +static inline void +detach_entity_load_avg(struct cfs_rq *cfs_rq, struct sched_entity *se) {} + static inline int idle_balance(struct rq *rq) { return 0; @@ -4816,32 +4875,39 @@ next: done: return target; } + /* - * get_cpu_usage returns the amount of capacity of a CPU that is used by CFS + * cpu_util returns the amount of capacity of a CPU that is used by CFS * tasks. The unit of the return value must be the one of capacity so we can - * compare the usage with the capacity of the CPU that is available for CFS - * task (ie cpu_capacity). - * cfs.avg.util_avg is the sum of running time of runnable tasks on a - * CPU. It represents the amount of utilization of a CPU in the range - * [0..SCHED_LOAD_SCALE]. The usage of a CPU can't be higher than the full - * capacity of the CPU because it's about the running time on this CPU. - * Nevertheless, cfs.avg.util_avg can be higher than SCHED_LOAD_SCALE - * because of unfortunate rounding in util_avg or just - * after migrating tasks until the average stabilizes with the new running - * time. So we need to check that the usage stays into the range - * [0..cpu_capacity_orig] and cap if necessary. - * Without capping the usage, a group could be seen as overloaded (CPU0 usage - * at 121% + CPU1 usage at 80%) whereas CPU1 has 20% of available capacity + * compare the utilization with the capacity of the CPU that is available for + * CFS task (ie cpu_capacity). + * + * cfs_rq.avg.util_avg is the sum of running time of runnable tasks plus the + * recent utilization of currently non-runnable tasks on a CPU. It represents + * the amount of utilization of a CPU in the range [0..capacity_orig] where + * capacity_orig is the cpu_capacity available at the highest frequency + * (arch_scale_freq_capacity()). + * The utilization of a CPU converges towards a sum equal to or less than the + * current capacity (capacity_curr <= capacity_orig) of the CPU because it is + * the running time on this CPU scaled by capacity_curr. + * + * Nevertheless, cfs_rq.avg.util_avg can be higher than capacity_curr or even + * higher than capacity_orig because of unfortunate rounding in + * cfs.avg.util_avg or just after migrating tasks and new task wakeups until + * the average stabilizes with the new running time. We need to check that the + * utilization stays within the range of [0..capacity_orig] and cap it if + * necessary. Without utilization capping, a group could be seen as overloaded + * (CPU0 utilization at 121% + CPU1 utilization at 80%) whereas CPU1 has 20% of + * available capacity. We allow utilization to overshoot capacity_curr (but not + * capacity_orig) as it useful for predicting the capacity required after task + * migrations (scheduler-driven DVFS). */ -static int get_cpu_usage(int cpu) +static int cpu_util(int cpu) { - unsigned long usage = cpu_rq(cpu)->cfs.avg.util_avg; + unsigned long util = cpu_rq(cpu)->cfs.avg.util_avg; unsigned long capacity = capacity_orig_of(cpu); - if (usage >= SCHED_LOAD_SCALE) - return capacity; - - return (usage * capacity) >> SCHED_LOAD_SHIFT; + return (util >= capacity) ? capacity : util; } /* @@ -4944,7 +5010,7 @@ select_task_rq_fair(struct task_struct *p, int prev_cpu, int sd_flag, int wake_f * previous cpu. However, the caller only guarantees p->pi_lock is held; no * other assumptions, including the state of rq->lock, should be made. */ -static void migrate_task_rq_fair(struct task_struct *p, int next_cpu) +static void migrate_task_rq_fair(struct task_struct *p) { /* * We are supposed to update the task to "current" time, then its up to date @@ -5524,10 +5590,10 @@ static int migrate_degrades_locality(struct task_struct *p, struct lb_env *env) unsigned long src_faults, dst_faults; int src_nid, dst_nid; - if (!p->numa_faults || !(env->sd->flags & SD_NUMA)) + if (!static_branch_likely(&sched_numa_balancing)) return -1; - if (!sched_feat(NUMA)) + if (!p->numa_faults || !(env->sd->flags & SD_NUMA)) return -1; src_nid = cpu_to_node(env->src_cpu); @@ -5933,7 +5999,7 @@ struct sg_lb_stats { unsigned long sum_weighted_load; /* Weighted load of group's tasks */ unsigned long load_per_task; unsigned long group_capacity; - unsigned long group_usage; /* Total usage of the group */ + unsigned long group_util; /* Total utilization of the group */ unsigned int sum_nr_running; /* Nr tasks running in the group */ unsigned int idle_cpus; unsigned int group_weight; @@ -6009,19 +6075,6 @@ static inline int get_sd_load_idx(struct sched_domain *sd, return load_idx; } -static unsigned long default_scale_cpu_capacity(struct sched_domain *sd, int cpu) -{ - if ((sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1)) - return sd->smt_gain / sd->span_weight; - - return SCHED_CAPACITY_SCALE; -} - -unsigned long __weak arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) -{ - return default_scale_cpu_capacity(sd, cpu); -} - static unsigned long scale_rt_capacity(int cpu) { struct rq *rq = cpu_rq(cpu); @@ -6051,16 +6104,9 @@ static unsigned long scale_rt_capacity(int cpu) static void update_cpu_capacity(struct sched_domain *sd, int cpu) { - unsigned long capacity = SCHED_CAPACITY_SCALE; + unsigned long capacity = arch_scale_cpu_capacity(sd, cpu); struct sched_group *sdg = sd->groups; - if (sched_feat(ARCH_CAPACITY)) - capacity *= arch_scale_cpu_capacity(sd, cpu); - else - capacity *= default_scale_cpu_capacity(sd, cpu); - - capacity >>= SCHED_CAPACITY_SHIFT; - cpu_rq(cpu)->cpu_capacity_orig = capacity; capacity *= scale_rt_capacity(cpu); @@ -6186,8 +6232,8 @@ static inline int sg_imbalanced(struct sched_group *group) * group_has_capacity returns true if the group has spare capacity that could * be used by some tasks. * We consider that a group has spare capacity if the * number of task is - * smaller than the number of CPUs or if the usage is lower than the available - * capacity for CFS tasks. + * smaller than the number of CPUs or if the utilization is lower than the + * available capacity for CFS tasks. * For the latter, we use a threshold to stabilize the state, to take into * account the variance of the tasks' load and to return true if the available * capacity in meaningful for the load balancer. @@ -6201,7 +6247,7 @@ group_has_capacity(struct lb_env *env, struct sg_lb_stats *sgs) return true; if ((sgs->group_capacity * 100) > - (sgs->group_usage * env->sd->imbalance_pct)) + (sgs->group_util * env->sd->imbalance_pct)) return true; return false; @@ -6222,15 +6268,15 @@ group_is_overloaded(struct lb_env *env, struct sg_lb_stats *sgs) return false; if ((sgs->group_capacity * 100) < - (sgs->group_usage * env->sd->imbalance_pct)) + (sgs->group_util * env->sd->imbalance_pct)) return true; return false; } -static enum group_type group_classify(struct lb_env *env, - struct sched_group *group, - struct sg_lb_stats *sgs) +static inline enum +group_type group_classify(struct sched_group *group, + struct sg_lb_stats *sgs) { if (sgs->group_no_capacity) return group_overloaded; @@ -6270,7 +6316,7 @@ static inline void update_sg_lb_stats(struct lb_env *env, load = source_load(i, load_idx); sgs->group_load += load; - sgs->group_usage += get_cpu_usage(i); + sgs->group_util += cpu_util(i); sgs->sum_nr_running += rq->cfs.h_nr_running; if (rq->nr_running > 1) @@ -6295,7 +6341,7 @@ static inline void update_sg_lb_stats(struct lb_env *env, sgs->group_weight = group->group_weight; sgs->group_no_capacity = group_is_overloaded(env, sgs); - sgs->group_type = group_classify(env, group, sgs); + sgs->group_type = group_classify(group, sgs); } /** @@ -6429,7 +6475,7 @@ static inline void update_sd_lb_stats(struct lb_env *env, struct sd_lb_stats *sd group_has_capacity(env, &sds->local_stat) && (sgs->sum_nr_running > 1)) { sgs->group_no_capacity = 1; - sgs->group_type = group_overloaded; + sgs->group_type = group_classify(sg, sgs); } if (update_sd_pick_busiest(env, sds, sg, sgs)) { @@ -7609,8 +7655,22 @@ out: * When the cpu is attached to null domain for ex, it will not be * updated. */ - if (likely(update_next_balance)) + if (likely(update_next_balance)) { rq->next_balance = next_balance; + +#ifdef CONFIG_NO_HZ_COMMON + /* + * If this CPU has been elected to perform the nohz idle + * balance. Other idle CPUs have already rebalanced with + * nohz_idle_balance() and nohz.next_balance has been + * updated accordingly. This CPU is now running the idle load + * balance for itself and we need to update the + * nohz.next_balance accordingly. + */ + if ((idle == CPU_IDLE) && time_after(nohz.next_balance, rq->next_balance)) + nohz.next_balance = rq->next_balance; +#endif + } } #ifdef CONFIG_NO_HZ_COMMON @@ -7623,6 +7683,9 @@ static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle) int this_cpu = this_rq->cpu; struct rq *rq; int balance_cpu; + /* Earliest time when we have to do rebalance again */ + unsigned long next_balance = jiffies + 60*HZ; + int update_next_balance = 0; if (idle != CPU_IDLE || !test_bit(NOHZ_BALANCE_KICK, nohz_flags(this_cpu))) @@ -7654,10 +7717,19 @@ static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle) rebalance_domains(rq, CPU_IDLE); } - if (time_after(this_rq->next_balance, rq->next_balance)) - this_rq->next_balance = rq->next_balance; + if (time_after(next_balance, rq->next_balance)) { + next_balance = rq->next_balance; + update_next_balance = 1; + } } - nohz.next_balance = this_rq->next_balance; + + /* + * next_balance will be updated only when there is a need. + * When the CPU is attached to null domain for ex, it will not be + * updated. + */ + if (likely(update_next_balance)) + nohz.next_balance = next_balance; end: clear_bit(NOHZ_BALANCE_KICK, nohz_flags(this_cpu)); } @@ -7810,7 +7882,7 @@ static void task_tick_fair(struct rq *rq, struct task_struct *curr, int queued) entity_tick(cfs_rq, se, queued); } - if (numabalancing_enabled) + if (static_branch_unlikely(&sched_numa_balancing)) task_tick_numa(rq, curr); } @@ -7886,21 +7958,39 @@ prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio) check_preempt_curr(rq, p, 0); } -static void switched_from_fair(struct rq *rq, struct task_struct *p) +static inline bool vruntime_normalized(struct task_struct *p) { struct sched_entity *se = &p->se; - struct cfs_rq *cfs_rq = cfs_rq_of(se); /* - * Ensure the task's vruntime is normalized, so that when it's - * switched back to the fair class the enqueue_entity(.flags=0) will - * do the right thing. + * In both the TASK_ON_RQ_QUEUED and TASK_ON_RQ_MIGRATING cases, + * the dequeue_entity(.flags=0) will already have normalized the + * vruntime. + */ + if (p->on_rq) + return true; + + /* + * When !on_rq, vruntime of the task has usually NOT been normalized. + * But there are some cases where it has already been normalized: * - * If it's queued, then the dequeue_entity(.flags=0) will already - * have normalized the vruntime, if it's !queued, then only when - * the task is sleeping will it still have non-normalized vruntime. + * - A forked child which is waiting for being woken up by + * wake_up_new_task(). + * - A task which has been woken up by try_to_wake_up() and + * waiting for actually being woken up by sched_ttwu_pending(). */ - if (!task_on_rq_queued(p) && p->state != TASK_RUNNING) { + if (!se->sum_exec_runtime || p->state == TASK_WAKING) + return true; + + return false; +} + +static void detach_task_cfs_rq(struct task_struct *p) +{ + struct sched_entity *se = &p->se; + struct cfs_rq *cfs_rq = cfs_rq_of(se); + + if (!vruntime_normalized(p)) { /* * Fix up our vruntime so that the current sleep doesn't * cause 'unlimited' sleep bonus. @@ -7909,28 +7999,14 @@ static void switched_from_fair(struct rq *rq, struct task_struct *p) se->vruntime -= cfs_rq->min_vruntime; } -#ifdef CONFIG_SMP /* Catch up with the cfs_rq and remove our load when we leave */ - __update_load_avg(cfs_rq->avg.last_update_time, cpu_of(rq), &se->avg, - se->on_rq * scale_load_down(se->load.weight), cfs_rq->curr == se, NULL); - - cfs_rq->avg.load_avg = - max_t(long, cfs_rq->avg.load_avg - se->avg.load_avg, 0); - cfs_rq->avg.load_sum = - max_t(s64, cfs_rq->avg.load_sum - se->avg.load_sum, 0); - cfs_rq->avg.util_avg = - max_t(long, cfs_rq->avg.util_avg - se->avg.util_avg, 0); - cfs_rq->avg.util_sum = - max_t(s32, cfs_rq->avg.util_sum - se->avg.util_sum, 0); -#endif + detach_entity_load_avg(cfs_rq, se); } -/* - * We switched to the sched_fair class. - */ -static void switched_to_fair(struct rq *rq, struct task_struct *p) +static void attach_task_cfs_rq(struct task_struct *p) { struct sched_entity *se = &p->se; + struct cfs_rq *cfs_rq = cfs_rq_of(se); #ifdef CONFIG_FAIR_GROUP_SCHED /* @@ -7940,31 +8016,33 @@ static void switched_to_fair(struct rq *rq, struct task_struct *p) se->depth = se->parent ? se->parent->depth + 1 : 0; #endif - if (!task_on_rq_queued(p)) { + /* Synchronize task with its cfs_rq */ + attach_entity_load_avg(cfs_rq, se); + + if (!vruntime_normalized(p)) + se->vruntime += cfs_rq->min_vruntime; +} + +static void switched_from_fair(struct rq *rq, struct task_struct *p) +{ + detach_task_cfs_rq(p); +} + +static void switched_to_fair(struct rq *rq, struct task_struct *p) +{ + attach_task_cfs_rq(p); + if (task_on_rq_queued(p)) { /* - * Ensure the task has a non-normalized vruntime when it is switched - * back to the fair class with !queued, so that enqueue_entity() at - * wake-up time will do the right thing. - * - * If it's queued, then the enqueue_entity(.flags=0) makes the task - * has non-normalized vruntime, if it's !queued, then it still has - * normalized vruntime. + * We were most likely switched from sched_rt, so + * kick off the schedule if running, otherwise just see + * if we can still preempt the current task. */ - if (p->state != TASK_RUNNING) - se->vruntime += cfs_rq_of(se)->min_vruntime; - return; + if (rq->curr == p) + resched_curr(rq); + else + check_preempt_curr(rq, p, 0); } - - /* - * We were most likely switched from sched_rt, so - * kick off the schedule if running, otherwise just see - * if we can still preempt the current task. - */ - if (rq->curr == p) - resched_curr(rq); - else - check_preempt_curr(rq, p, 0); } /* Account for a task changing its policy or group. @@ -7999,56 +8077,16 @@ void init_cfs_rq(struct cfs_rq *cfs_rq) } #ifdef CONFIG_FAIR_GROUP_SCHED -static void task_move_group_fair(struct task_struct *p, int queued) +static void task_move_group_fair(struct task_struct *p) { - struct sched_entity *se = &p->se; - struct cfs_rq *cfs_rq; - - /* - * If the task was not on the rq at the time of this cgroup movement - * it must have been asleep, sleeping tasks keep their ->vruntime - * absolute on their old rq until wakeup (needed for the fair sleeper - * bonus in place_entity()). - * - * If it was on the rq, we've just 'preempted' it, which does convert - * ->vruntime to a relative base. - * - * Make sure both cases convert their relative position when migrating - * to another cgroup's rq. This does somewhat interfere with the - * fair sleeper stuff for the first placement, but who cares. - */ - /* - * When !queued, vruntime of the task has usually NOT been normalized. - * But there are some cases where it has already been normalized: - * - * - Moving a forked child which is waiting for being woken up by - * wake_up_new_task(). - * - Moving a task which has been woken up by try_to_wake_up() and - * waiting for actually being woken up by sched_ttwu_pending(). - * - * To prevent boost or penalty in the new cfs_rq caused by delta - * min_vruntime between the two cfs_rqs, we skip vruntime adjustment. - */ - if (!queued && (!se->sum_exec_runtime || p->state == TASK_WAKING)) - queued = 1; - - if (!queued) - se->vruntime -= cfs_rq_of(se)->min_vruntime; + detach_task_cfs_rq(p); set_task_rq(p, task_cpu(p)); - se->depth = se->parent ? se->parent->depth + 1 : 0; - if (!queued) { - cfs_rq = cfs_rq_of(se); - se->vruntime += cfs_rq->min_vruntime; #ifdef CONFIG_SMP - /* Virtually synchronize task with its new cfs_rq */ - p->se.avg.last_update_time = cfs_rq->avg.last_update_time; - cfs_rq->avg.load_avg += p->se.avg.load_avg; - cfs_rq->avg.load_sum += p->se.avg.load_sum; - cfs_rq->avg.util_avg += p->se.avg.util_avg; - cfs_rq->avg.util_sum += p->se.avg.util_sum; + /* Tell se's cfs_rq has been changed -- migrated */ + p->se.avg.last_update_time = 0; #endif - } + attach_task_cfs_rq(p); } void free_fair_sched_group(struct task_group *tg) diff --git a/kernel/sched/features.h b/kernel/sched/features.h index 83a50e7ca533..69631fa46c2f 100644 --- a/kernel/sched/features.h +++ b/kernel/sched/features.h @@ -36,11 +36,6 @@ SCHED_FEAT(CACHE_HOT_BUDDY, true) */ SCHED_FEAT(WAKEUP_PREEMPTION, true) -/* - * Use arch dependent cpu capacity functions - */ -SCHED_FEAT(ARCH_CAPACITY, true) - SCHED_FEAT(HRTICK, false) SCHED_FEAT(DOUBLE_TICK, false) SCHED_FEAT(LB_BIAS, true) @@ -72,19 +67,5 @@ SCHED_FEAT(RT_PUSH_IPI, true) SCHED_FEAT(FORCE_SD_OVERLAP, false) SCHED_FEAT(RT_RUNTIME_SHARE, true) SCHED_FEAT(LB_MIN, false) +SCHED_FEAT(ATTACH_AGE_LOAD, true) -/* - * Apply the automatic NUMA scheduling policy. Enabled automatically - * at runtime if running on a NUMA machine. Can be controlled via - * numa_balancing= - */ -#ifdef CONFIG_NUMA_BALANCING - -/* - * NUMA will favor moving tasks towards nodes where a higher number of - * hinting faults are recorded during active load balancing. It will - * resist moving tasks towards nodes where a lower number of hinting - * faults have been recorded. - */ -SCHED_FEAT(NUMA, true) -#endif diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index 8f177c73ae19..4a2ef5a02fd3 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -57,9 +57,11 @@ static inline int cpu_idle_poll(void) rcu_idle_enter(); trace_cpu_idle_rcuidle(0, smp_processor_id()); local_irq_enable(); + stop_critical_timings(); while (!tif_need_resched() && (cpu_idle_force_poll || tick_check_broadcast_expired())) cpu_relax(); + start_critical_timings(); trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, smp_processor_id()); rcu_idle_exit(); return 1; diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index d2ea59364a1c..e3cc16312046 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -635,11 +635,11 @@ bool sched_rt_bandwidth_account(struct rt_rq *rt_rq) /* * We ran out of runtime, see if we can borrow some from our neighbours. */ -static int do_balance_runtime(struct rt_rq *rt_rq) +static void do_balance_runtime(struct rt_rq *rt_rq) { struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq); struct root_domain *rd = rq_of_rt_rq(rt_rq)->rd; - int i, weight, more = 0; + int i, weight; u64 rt_period; weight = cpumask_weight(rd->span); @@ -673,7 +673,6 @@ static int do_balance_runtime(struct rt_rq *rt_rq) diff = rt_period - rt_rq->rt_runtime; iter->rt_runtime -= diff; rt_rq->rt_runtime += diff; - more = 1; if (rt_rq->rt_runtime == rt_period) { raw_spin_unlock(&iter->rt_runtime_lock); break; @@ -683,8 +682,6 @@ next: raw_spin_unlock(&iter->rt_runtime_lock); } raw_spin_unlock(&rt_b->rt_runtime_lock); - - return more; } /* @@ -796,26 +793,19 @@ static void __enable_runtime(struct rq *rq) } } -static int balance_runtime(struct rt_rq *rt_rq) +static void balance_runtime(struct rt_rq *rt_rq) { - int more = 0; - if (!sched_feat(RT_RUNTIME_SHARE)) - return more; + return; if (rt_rq->rt_time > rt_rq->rt_runtime) { raw_spin_unlock(&rt_rq->rt_runtime_lock); - more = do_balance_runtime(rt_rq); + do_balance_runtime(rt_rq); raw_spin_lock(&rt_rq->rt_runtime_lock); } - - return more; } #else /* !CONFIG_SMP */ -static inline int balance_runtime(struct rt_rq *rt_rq) -{ - return 0; -} +static inline void balance_runtime(struct rt_rq *rt_rq) {} #endif /* CONFIG_SMP */ static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun) diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 68cda117574c..efd3bfc7e347 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -84,6 +84,10 @@ static inline void update_cpu_load_active(struct rq *this_rq) { } */ #define RUNTIME_INF ((u64)~0ULL) +static inline int idle_policy(int policy) +{ + return policy == SCHED_IDLE; +} static inline int fair_policy(int policy) { return policy == SCHED_NORMAL || policy == SCHED_BATCH; @@ -98,6 +102,11 @@ static inline int dl_policy(int policy) { return policy == SCHED_DEADLINE; } +static inline bool valid_policy(int policy) +{ + return idle_policy(policy) || fair_policy(policy) || + rt_policy(policy) || dl_policy(policy); +} static inline int task_has_rt_policy(struct task_struct *p) { @@ -109,11 +118,6 @@ static inline int task_has_dl_policy(struct task_struct *p) return dl_policy(p->policy); } -static inline bool dl_time_before(u64 a, u64 b) -{ - return (s64)(a - b) < 0; -} - /* * Tells if entity @a should preempt entity @b. */ @@ -1003,17 +1007,7 @@ extern struct static_key sched_feat_keys[__SCHED_FEAT_NR]; #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x)) #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */ -#ifdef CONFIG_NUMA_BALANCING -#define sched_feat_numa(x) sched_feat(x) -#ifdef CONFIG_SCHED_DEBUG -#define numabalancing_enabled sched_feat_numa(NUMA) -#else -extern bool numabalancing_enabled; -#endif /* CONFIG_SCHED_DEBUG */ -#else -#define sched_feat_numa(x) (0) -#define numabalancing_enabled (0) -#endif /* CONFIG_NUMA_BALANCING */ +extern struct static_key_false sched_numa_balancing; static inline u64 global_rt_period(void) { @@ -1078,9 +1072,10 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev) * After ->on_cpu is cleared, the task can be moved to a different CPU. * We must ensure this doesn't happen until the switch is completely * finished. + * + * Pairs with the control dependency and rmb in try_to_wake_up(). */ - smp_wmb(); - prev->on_cpu = 0; + smp_store_release(&prev->on_cpu, 0); #endif #ifdef CONFIG_DEBUG_SPINLOCK /* this is a valid case when another task releases the spinlock */ @@ -1156,16 +1151,18 @@ static const u32 prio_to_wmult[40] = { /* 15 */ 119304647, 148102320, 186737708, 238609294, 286331153, }; -#define ENQUEUE_WAKEUP 1 -#define ENQUEUE_HEAD 2 +#define ENQUEUE_WAKEUP 0x01 +#define ENQUEUE_HEAD 0x02 #ifdef CONFIG_SMP -#define ENQUEUE_WAKING 4 /* sched_class::task_waking was called */ +#define ENQUEUE_WAKING 0x04 /* sched_class::task_waking was called */ #else -#define ENQUEUE_WAKING 0 +#define ENQUEUE_WAKING 0x00 #endif -#define ENQUEUE_REPLENISH 8 +#define ENQUEUE_REPLENISH 0x08 +#define ENQUEUE_RESTORE 0x10 -#define DEQUEUE_SLEEP 1 +#define DEQUEUE_SLEEP 0x01 +#define DEQUEUE_SAVE 0x02 #define RETRY_TASK ((void *)-1UL) @@ -1193,7 +1190,7 @@ struct sched_class { #ifdef CONFIG_SMP int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags); - void (*migrate_task_rq)(struct task_struct *p, int next_cpu); + void (*migrate_task_rq)(struct task_struct *p); void (*task_waking) (struct task_struct *task); void (*task_woken) (struct rq *this_rq, struct task_struct *task); @@ -1226,7 +1223,7 @@ struct sched_class { void (*update_curr) (struct rq *rq); #ifdef CONFIG_FAIR_GROUP_SCHED - void (*task_move_group) (struct task_struct *p, int on_rq); + void (*task_move_group) (struct task_struct *p); #endif }; @@ -1404,6 +1401,17 @@ unsigned long arch_scale_freq_capacity(struct sched_domain *sd, int cpu) } #endif +#ifndef arch_scale_cpu_capacity +static __always_inline +unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu) +{ + if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1)) + return sd->smt_gain / sd->span_weight; + + return SCHED_CAPACITY_SCALE; +} +#endif + static inline void sched_rt_avg_update(struct rq *rq, u64 rt_delta) { rq->rt_avg += rt_delta * arch_scale_freq_capacity(NULL, cpu_of(rq)); diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 5bd4779282df..580ac2d4024f 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -347,6 +347,7 @@ static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog) { struct seccomp_filter *sfilter; int ret; + const bool save_orig = config_enabled(CONFIG_CHECKPOINT_RESTORE); if (fprog->len == 0 || fprog->len > BPF_MAXINSNS) return ERR_PTR(-EINVAL); @@ -370,7 +371,7 @@ static struct seccomp_filter *seccomp_prepare_filter(struct sock_fprog *fprog) return ERR_PTR(-ENOMEM); ret = bpf_prog_create_from_user(&sfilter->prog, fprog, - seccomp_check_filter); + seccomp_check_filter, save_orig); if (ret < 0) { kfree(sfilter); return ERR_PTR(ret); @@ -469,7 +470,7 @@ void get_seccomp_filter(struct task_struct *tsk) static inline void seccomp_filter_free(struct seccomp_filter *filter) { if (filter) { - bpf_prog_free(filter->prog); + bpf_prog_destroy(filter->prog); kfree(filter); } } @@ -867,3 +868,76 @@ long prctl_set_seccomp(unsigned long seccomp_mode, char __user *filter) /* prctl interface doesn't have flags, so they are always zero. */ return do_seccomp(op, 0, uargs); } + +#if defined(CONFIG_SECCOMP_FILTER) && defined(CONFIG_CHECKPOINT_RESTORE) +long seccomp_get_filter(struct task_struct *task, unsigned long filter_off, + void __user *data) +{ + struct seccomp_filter *filter; + struct sock_fprog_kern *fprog; + long ret; + unsigned long count = 0; + + if (!capable(CAP_SYS_ADMIN) || + current->seccomp.mode != SECCOMP_MODE_DISABLED) { + return -EACCES; + } + + spin_lock_irq(&task->sighand->siglock); + if (task->seccomp.mode != SECCOMP_MODE_FILTER) { + ret = -EINVAL; + goto out; + } + + filter = task->seccomp.filter; + while (filter) { + filter = filter->prev; + count++; + } + + if (filter_off >= count) { + ret = -ENOENT; + goto out; + } + count -= filter_off; + + filter = task->seccomp.filter; + while (filter && count > 1) { + filter = filter->prev; + count--; + } + + if (WARN_ON(count != 1 || !filter)) { + /* The filter tree shouldn't shrink while we're using it. */ + ret = -ENOENT; + goto out; + } + + fprog = filter->prog->orig_prog; + if (!fprog) { + /* This must be a new non-cBPF filter, since we save every + * every cBPF filter's orig_prog above when + * CONFIG_CHECKPOINT_RESTORE is enabled. + */ + ret = -EMEDIUMTYPE; + goto out; + } + + ret = fprog->len; + if (!data) + goto out; + + get_seccomp_filter(task); + spin_unlock_irq(&task->sighand->siglock); + + if (copy_to_user(data, fprog->filter, bpf_classic_proglen(fprog))) + ret = -EFAULT; + + put_seccomp_filter(task); + return ret; + +out: + spin_unlock_irq(&task->sighand->siglock); + return ret; +} +#endif diff --git a/kernel/signal.c b/kernel/signal.c index 0f6bbbe77b46..c0b01fe24bbd 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -503,41 +503,6 @@ int unhandled_signal(struct task_struct *tsk, int sig) return !tsk->ptrace; } -/* - * Notify the system that a driver wants to block all signals for this - * process, and wants to be notified if any signals at all were to be - * sent/acted upon. If the notifier routine returns non-zero, then the - * signal will be acted upon after all. If the notifier routine returns 0, - * then then signal will be blocked. Only one block per process is - * allowed. priv is a pointer to private data that the notifier routine - * can use to determine if the signal should be blocked or not. - */ -void -block_all_signals(int (*notifier)(void *priv), void *priv, sigset_t *mask) -{ - unsigned long flags; - - spin_lock_irqsave(¤t->sighand->siglock, flags); - current->notifier_mask = mask; - current->notifier_data = priv; - current->notifier = notifier; - spin_unlock_irqrestore(¤t->sighand->siglock, flags); -} - -/* Notify the system that blocking has ended. */ - -void -unblock_all_signals(void) -{ - unsigned long flags; - - spin_lock_irqsave(¤t->sighand->siglock, flags); - current->notifier = NULL; - current->notifier_data = NULL; - recalc_sigpending(); - spin_unlock_irqrestore(¤t->sighand->siglock, flags); -} - static void collect_signal(int sig, struct sigpending *list, siginfo_t *info) { struct sigqueue *q, *first = NULL; @@ -580,19 +545,8 @@ static int __dequeue_signal(struct sigpending *pending, sigset_t *mask, { int sig = next_signal(pending, mask); - if (sig) { - if (current->notifier) { - if (sigismember(current->notifier_mask, sig)) { - if (!(current->notifier)(current->notifier_data)) { - clear_thread_flag(TIF_SIGPENDING); - return 0; - } - } - } - + if (sig) collect_signal(sig, pending, info); - } - return sig; } @@ -834,7 +788,7 @@ static bool prepare_signal(int sig, struct task_struct *p, bool force) sigset_t flush; if (signal->flags & (SIGNAL_GROUP_EXIT | SIGNAL_GROUP_COREDUMP)) { - if (signal->flags & SIGNAL_GROUP_COREDUMP) + if (!(signal->flags & SIGNAL_GROUP_EXIT)) return sig == SIGKILL; /* * The process is in the middle of dying, nothing to do. @@ -2483,9 +2437,6 @@ EXPORT_SYMBOL(force_sig); EXPORT_SYMBOL(send_sig); EXPORT_SYMBOL(send_sig_info); EXPORT_SYMBOL(sigprocmask); -EXPORT_SYMBOL(block_all_signals); -EXPORT_SYMBOL(unblock_all_signals); - /* * System call entry points. diff --git a/kernel/smp.c b/kernel/smp.c index 07854477c164..d903c02223af 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -669,7 +669,7 @@ void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info), cpumask_var_t cpus; int cpu, ret; - might_sleep_if(gfp_flags & __GFP_WAIT); + might_sleep_if(gfpflags_allow_blocking(gfp_flags)); if (likely(zalloc_cpumask_var(&cpus, (gfp_flags|__GFP_NOWARN)))) { preempt_disable(); diff --git a/kernel/smpboot.c b/kernel/smpboot.c index a818cbc73e14..d264f59bff56 100644 --- a/kernel/smpboot.c +++ b/kernel/smpboot.c @@ -222,9 +222,8 @@ static void smpboot_unpark_thread(struct smp_hotplug_thread *ht, unsigned int cp { struct task_struct *tsk = *per_cpu_ptr(ht->store, cpu); - if (ht->pre_unpark) - ht->pre_unpark(cpu); - kthread_unpark(tsk); + if (!ht->selfparking) + kthread_unpark(tsk); } void smpboot_unpark_threads(unsigned int cpu) diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c index 12484e5d5c88..867bc20e1ef1 100644 --- a/kernel/stop_machine.c +++ b/kernel/stop_machine.c @@ -73,21 +73,24 @@ static void cpu_stop_signal_done(struct cpu_stop_done *done, bool executed) } } +static void __cpu_stop_queue_work(struct cpu_stopper *stopper, + struct cpu_stop_work *work) +{ + list_add_tail(&work->list, &stopper->works); + wake_up_process(stopper->thread); +} + /* queue @work to @stopper. if offline, @work is completed immediately */ static void cpu_stop_queue_work(unsigned int cpu, struct cpu_stop_work *work) { struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu); - unsigned long flags; spin_lock_irqsave(&stopper->lock, flags); - - if (stopper->enabled) { - list_add_tail(&work->list, &stopper->works); - wake_up_process(stopper->thread); - } else + if (stopper->enabled) + __cpu_stop_queue_work(stopper, work); + else cpu_stop_signal_done(work->done, false); - spin_unlock_irqrestore(&stopper->lock, flags); } @@ -213,6 +216,31 @@ static int multi_cpu_stop(void *data) return err; } +static int cpu_stop_queue_two_works(int cpu1, struct cpu_stop_work *work1, + int cpu2, struct cpu_stop_work *work2) +{ + struct cpu_stopper *stopper1 = per_cpu_ptr(&cpu_stopper, cpu1); + struct cpu_stopper *stopper2 = per_cpu_ptr(&cpu_stopper, cpu2); + int err; + + lg_double_lock(&stop_cpus_lock, cpu1, cpu2); + spin_lock_irq(&stopper1->lock); + spin_lock_nested(&stopper2->lock, SINGLE_DEPTH_NESTING); + + err = -ENOENT; + if (!stopper1->enabled || !stopper2->enabled) + goto unlock; + + err = 0; + __cpu_stop_queue_work(stopper1, work1); + __cpu_stop_queue_work(stopper2, work2); +unlock: + spin_unlock(&stopper2->lock); + spin_unlock_irq(&stopper1->lock); + lg_double_unlock(&stop_cpus_lock, cpu1, cpu2); + + return err; +} /** * stop_two_cpus - stops two cpus * @cpu1: the cpu to stop @@ -247,24 +275,13 @@ int stop_two_cpus(unsigned int cpu1, unsigned int cpu2, cpu_stop_fn_t fn, void * cpu_stop_init_done(&done, 2); set_state(&msdata, MULTI_STOP_PREPARE); - /* - * If we observe both CPUs active we know _cpu_down() cannot yet have - * queued its stop_machine works and therefore ours will get executed - * first. Or its not either one of our CPUs that's getting unplugged, - * in which case we don't care. - * - * This relies on the stopper workqueues to be FIFO. - */ - if (!cpu_active(cpu1) || !cpu_active(cpu2)) { + if (cpu1 > cpu2) + swap(cpu1, cpu2); + if (cpu_stop_queue_two_works(cpu1, &work1, cpu2, &work2)) { preempt_enable(); return -ENOENT; } - lg_double_lock(&stop_cpus_lock, cpu1, cpu2); - cpu_stop_queue_work(cpu1, &work1); - cpu_stop_queue_work(cpu2, &work2); - lg_double_unlock(&stop_cpus_lock, cpu1, cpu2); - preempt_enable(); wait_for_completion(&done.completion); @@ -452,6 +469,18 @@ repeat: } } +void stop_machine_park(int cpu) +{ + struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu); + /* + * Lockless. cpu_stopper_thread() will take stopper->lock and flush + * the pending works before it parks, until then it is fine to queue + * the new works. + */ + stopper->enabled = false; + kthread_park(stopper->thread); +} + extern void sched_set_stop_task(int cpu, struct task_struct *stop); static void cpu_stop_create(unsigned int cpu) @@ -462,26 +491,16 @@ static void cpu_stop_create(unsigned int cpu) static void cpu_stop_park(unsigned int cpu) { struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu); - struct cpu_stop_work *work, *tmp; - unsigned long flags; - /* drain remaining works */ - spin_lock_irqsave(&stopper->lock, flags); - list_for_each_entry_safe(work, tmp, &stopper->works, list) { - list_del_init(&work->list); - cpu_stop_signal_done(work->done, false); - } - stopper->enabled = false; - spin_unlock_irqrestore(&stopper->lock, flags); + WARN_ON(!list_empty(&stopper->works)); } -static void cpu_stop_unpark(unsigned int cpu) +void stop_machine_unpark(int cpu) { struct cpu_stopper *stopper = &per_cpu(cpu_stopper, cpu); - spin_lock_irq(&stopper->lock); stopper->enabled = true; - spin_unlock_irq(&stopper->lock); + kthread_unpark(stopper->thread); } static struct smp_hotplug_thread cpu_stop_threads = { @@ -490,9 +509,7 @@ static struct smp_hotplug_thread cpu_stop_threads = { .thread_fn = cpu_stopper_thread, .thread_comm = "migration/%u", .create = cpu_stop_create, - .setup = cpu_stop_unpark, .park = cpu_stop_park, - .pre_unpark = cpu_stop_unpark, .selfparking = true, }; @@ -508,6 +525,7 @@ static int __init cpu_stop_init(void) } BUG_ON(smpboot_register_percpu_thread(&cpu_stop_threads)); + stop_machine_unpark(raw_smp_processor_id()); stop_machine_initialized = true; return 0; } diff --git a/kernel/sys.c b/kernel/sys.c index fa2f2f671a5c..6af9212ab5aa 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -222,7 +222,7 @@ SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval) goto out_unlock; /* No processes for this user */ } do_each_thread(g, p) { - if (uid_eq(task_uid(p), uid)) + if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) error = set_one_prio(p, niceval, error); } while_each_thread(g, p); if (!uid_eq(uid, cred->uid)) @@ -290,7 +290,7 @@ SYSCALL_DEFINE2(getpriority, int, which, int, who) goto out_unlock; /* No processes for this user */ } do_each_thread(g, p) { - if (uid_eq(task_uid(p), uid)) { + if (uid_eq(task_uid(p), uid) && task_pid_vnr(p)) { niceval = nice_to_rlimit(task_nice(p)); if (niceval > retval) retval = niceval; diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index a02decf15583..0623787ec67a 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -194,6 +194,7 @@ cond_syscall(sys_mlock); cond_syscall(sys_munlock); cond_syscall(sys_mlockall); cond_syscall(sys_munlockall); +cond_syscall(sys_mlock2); cond_syscall(sys_mincore); cond_syscall(sys_madvise); cond_syscall(sys_mremap); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index e69201d8094e..dc6858d6639e 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -64,6 +64,7 @@ #include <linux/binfmts.h> #include <linux/sched/sysctl.h> #include <linux/kexec.h> +#include <linux/bpf.h> #include <asm/uaccess.h> #include <asm/processor.h> @@ -887,6 +888,17 @@ static struct ctl_table kern_table[] = { .extra1 = &zero, .extra2 = &one, }, +#ifdef CONFIG_HARDLOCKUP_DETECTOR + { + .procname = "hardlockup_panic", + .data = &hardlockup_panic, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, + }, +#endif #ifdef CONFIG_SMP { .procname = "softlockup_all_cpu_backtrace", @@ -897,6 +909,15 @@ static struct ctl_table kern_table[] = { .extra1 = &zero, .extra2 = &one, }, + { + .procname = "hardlockup_all_cpu_backtrace", + .data = &sysctl_hardlockup_all_cpu_backtrace, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = &zero, + .extra2 = &one, + }, #endif /* CONFIG_SMP */ #endif #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86) @@ -1139,6 +1160,18 @@ static struct ctl_table kern_table[] = { .proc_handler = timer_migration_handler, }, #endif +#ifdef CONFIG_BPF_SYSCALL + { + .procname = "unprivileged_bpf_disabled", + .data = &sysctl_unprivileged_bpf_disabled, + .maxlen = sizeof(sysctl_unprivileged_bpf_disabled), + .mode = 0644, + /* only handle a transition from default "0" to "1" */ + .proc_handler = proc_dointvec_minmax, + .extra1 = &one, + .extra2 = &one, + }, +#endif { } }; diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c index 841b72f720e8..1347882d131e 100644 --- a/kernel/time/clocksource.c +++ b/kernel/time/clocksource.c @@ -217,7 +217,7 @@ static void clocksource_watchdog(unsigned long data) continue; /* Check the deviation from the watchdog clocksource. */ - if ((abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD)) { + if (abs(cs_nsec - wd_nsec) > WATCHDOG_THRESHOLD) { pr_warn("timekeeping watchdog: Marking clocksource '%s' as unstable because the skew is too large:\n", cs->name); pr_warn(" '%s' wd_now: %llx wd_last: %llx mask: %llx\n", @@ -479,7 +479,7 @@ static u32 clocksource_max_adjustment(struct clocksource *cs) * return half the number of nanoseconds the hardware counter can technically * cover. This is done so that we can potentially detect problems caused by * delayed timers or bad hardware, which might result in time intervals that - * are larger then what the math used can handle without overflows. + * are larger than what the math used can handle without overflows. */ u64 clocks_calc_max_nsecs(u32 mult, u32 shift, u32 maxadj, u64 mask, u64 *max_cyc) { @@ -595,16 +595,15 @@ static void __clocksource_select(bool skipcur) */ static void clocksource_select(void) { - return __clocksource_select(false); + __clocksource_select(false); } static void clocksource_select_fallback(void) { - return __clocksource_select(true); + __clocksource_select(true); } #else /* !CONFIG_ARCH_USES_GETTIMEOFFSET */ - static inline void clocksource_select(void) { } static inline void clocksource_select_fallback(void) { } diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 457a373e2181..435b8850dd80 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -59,7 +59,7 @@ /* * The timer bases: * - * There are more clockids then hrtimer bases. Thus, we index + * There are more clockids than hrtimer bases. Thus, we index * into the timer bases by the hrtimer_base_type enum. When trying * to reach a base using a clockid, hrtimer_clockid_to_base() * is used to convert from clockid to the proper hrtimer_base_type. diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c index df68cb875248..149cc8086aea 100644 --- a/kernel/time/ntp.c +++ b/kernel/time/ntp.c @@ -99,7 +99,7 @@ static time64_t ntp_next_leap_sec = TIME64_MAX; static int pps_valid; /* signal watchdog counter */ static long pps_tf[3]; /* phase median filter */ static long pps_jitter; /* current jitter (ns) */ -static struct timespec pps_fbase; /* beginning of the last freq interval */ +static struct timespec64 pps_fbase; /* beginning of the last freq interval */ static int pps_shift; /* current interval duration (s) (shift) */ static int pps_intcnt; /* interval counter */ static s64 pps_freq; /* frequency offset (scaled ns/s) */ @@ -509,7 +509,7 @@ static DECLARE_DELAYED_WORK(sync_cmos_work, sync_cmos_clock); static void sync_cmos_clock(struct work_struct *work) { struct timespec64 now; - struct timespec next; + struct timespec64 next; int fail = 1; /* @@ -559,7 +559,7 @@ static void sync_cmos_clock(struct work_struct *work) next.tv_nsec -= NSEC_PER_SEC; } queue_delayed_work(system_power_efficient_wq, - &sync_cmos_work, timespec_to_jiffies(&next)); + &sync_cmos_work, timespec64_to_jiffies(&next)); } void ntp_notify_cmos_timer(void) @@ -773,13 +773,13 @@ int __do_adjtimex(struct timex *txc, struct timespec64 *ts, s32 *time_tai) * pps_normtime.nsec has a range of ( -NSEC_PER_SEC / 2, NSEC_PER_SEC / 2 ] * while timespec.tv_nsec has a range of [0, NSEC_PER_SEC) */ struct pps_normtime { - __kernel_time_t sec; /* seconds */ + s64 sec; /* seconds */ long nsec; /* nanoseconds */ }; /* normalize the timestamp so that nsec is in the ( -NSEC_PER_SEC / 2, NSEC_PER_SEC / 2 ] interval */ -static inline struct pps_normtime pps_normalize_ts(struct timespec ts) +static inline struct pps_normtime pps_normalize_ts(struct timespec64 ts) { struct pps_normtime norm = { .sec = ts.tv_sec, @@ -861,7 +861,7 @@ static long hardpps_update_freq(struct pps_normtime freq_norm) pps_errcnt++; pps_dec_freq_interval(); printk_deferred(KERN_ERR - "hardpps: PPSERROR: interval too long - %ld s\n", + "hardpps: PPSERROR: interval too long - %lld s\n", freq_norm.sec); return 0; } @@ -948,7 +948,7 @@ static void hardpps_update_phase(long error) * This code is based on David Mills's reference nanokernel * implementation. It was mostly rewritten but keeps the same idea. */ -void __hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) +void __hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts) { struct pps_normtime pts_norm, freq_norm; @@ -969,7 +969,7 @@ void __hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) } /* ok, now we have a base for frequency calculation */ - freq_norm = pps_normalize_ts(timespec_sub(*raw_ts, pps_fbase)); + freq_norm = pps_normalize_ts(timespec64_sub(*raw_ts, pps_fbase)); /* check that the signal is in the range * [1s - MAXFREQ us, 1s + MAXFREQ us], otherwise reject it */ diff --git a/kernel/time/ntp_internal.h b/kernel/time/ntp_internal.h index 65430504ca26..af924470eac0 100644 --- a/kernel/time/ntp_internal.h +++ b/kernel/time/ntp_internal.h @@ -9,5 +9,5 @@ extern ktime_t ntp_get_next_leap(void); extern int second_overflow(unsigned long secs); extern int ntp_validate_timex(struct timex *); extern int __do_adjtimex(struct timex *, struct timespec64 *, s32 *); -extern void __hardpps(const struct timespec *, const struct timespec *); +extern void __hardpps(const struct timespec64 *, const struct timespec64 *); #endif /* _LINUX_NTP_INTERNAL_H */ diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c index 892e3dae0aac..f5e86d282d52 100644 --- a/kernel/time/posix-cpu-timers.c +++ b/kernel/time/posix-cpu-timers.c @@ -249,7 +249,7 @@ void thread_group_cputimer(struct task_struct *tsk, struct task_cputime *times) * but barriers are not required because update_gt_cputime() * can handle concurrent updates. */ - WRITE_ONCE(cputimer->running, 1); + WRITE_ONCE(cputimer->running, true); } sample_cputime_atomic(times, &cputimer->cputime_atomic); } @@ -864,6 +864,13 @@ static void check_thread_timers(struct task_struct *tsk, unsigned long long expires; unsigned long soft; + /* + * If cputime_expires is zero, then there are no active + * per thread CPU timers. + */ + if (task_cputime_zero(&tsk->cputime_expires)) + return; + expires = check_timers_list(timers, firing, prof_ticks(tsk)); tsk_expires->prof_exp = expires_to_cputime(expires); @@ -911,7 +918,7 @@ static inline void stop_process_timers(struct signal_struct *sig) struct thread_group_cputimer *cputimer = &sig->cputimer; /* Turn off cputimer->running. This is done without locking. */ - WRITE_ONCE(cputimer->running, 0); + WRITE_ONCE(cputimer->running, false); } static u32 onecputick; @@ -962,6 +969,19 @@ static void check_process_timers(struct task_struct *tsk, unsigned long soft; /* + * If cputimer is not running, then there are no active + * process wide timers (POSIX 1.b, itimers, RLIMIT_CPU). + */ + if (!READ_ONCE(tsk->signal->cputimer.running)) + return; + + /* + * Signify that a thread is checking for process timers. + * Write access to this field is protected by the sighand lock. + */ + sig->cputimer.checking_timer = true; + + /* * Collect the current process totals. */ thread_group_cputimer(tsk, &cputime); @@ -1015,6 +1035,8 @@ static void check_process_timers(struct task_struct *tsk, sig->cputime_expires.sched_exp = sched_expires; if (task_cputime_zero(&sig->cputime_expires)) stop_process_timers(sig); + + sig->cputimer.checking_timer = false; } /* @@ -1117,24 +1139,33 @@ static inline int task_cputime_expired(const struct task_cputime *sample, static inline int fastpath_timer_check(struct task_struct *tsk) { struct signal_struct *sig; - cputime_t utime, stime; - - task_cputime(tsk, &utime, &stime); if (!task_cputime_zero(&tsk->cputime_expires)) { - struct task_cputime task_sample = { - .utime = utime, - .stime = stime, - .sum_exec_runtime = tsk->se.sum_exec_runtime - }; + struct task_cputime task_sample; + task_cputime(tsk, &task_sample.utime, &task_sample.stime); + task_sample.sum_exec_runtime = tsk->se.sum_exec_runtime; if (task_cputime_expired(&task_sample, &tsk->cputime_expires)) return 1; } sig = tsk->signal; - /* Check if cputimer is running. This is accessed without locking. */ - if (READ_ONCE(sig->cputimer.running)) { + /* + * Check if thread group timers expired when the cputimer is + * running and no other thread in the group is already checking + * for thread group cputimers. These fields are read without the + * sighand lock. However, this is fine because this is meant to + * be a fastpath heuristic to determine whether we should try to + * acquire the sighand lock to check/handle timers. + * + * In the worst case scenario, if 'running' or 'checking_timer' gets + * set but the current thread doesn't see the change yet, we'll wait + * until the next thread in the group gets a scheduler interrupt to + * handle the timer. This isn't an issue in practice because these + * types of delays with signals actually getting sent are expected. + */ + if (READ_ONCE(sig->cputimer.running) && + !READ_ONCE(sig->cputimer.checking_timer)) { struct task_cputime group_sample; sample_cputime_atomic(&group_sample, &sig->cputimer.cputime_atomic); @@ -1174,12 +1205,8 @@ void run_posix_cpu_timers(struct task_struct *tsk) * put them on the firing list. */ check_thread_timers(tsk, &firing); - /* - * If there are any active process wide timers (POSIX 1.b, itimers, - * RLIMIT_CPU) cputimer must be running. - */ - if (READ_ONCE(tsk->signal->cputimer.running)) - check_process_timers(tsk, &firing); + + check_process_timers(tsk, &firing); /* * We must release these locks before taking any timer's lock. diff --git a/kernel/time/timeconst.bc b/kernel/time/timeconst.bc index c7388dee8635..c48688904f9f 100644 --- a/kernel/time/timeconst.bc +++ b/kernel/time/timeconst.bc @@ -39,7 +39,7 @@ define fmuls(b,n,d) { } define timeconst(hz) { - print "/* Automatically generated by kernel/timeconst.bc */\n" + print "/* Automatically generated by kernel/time/timeconst.bc */\n" print "/* Time conversion constants for HZ == ", hz, " */\n" print "\n" diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c index 3739ac6aa473..d563c1960302 100644 --- a/kernel/time/timekeeping.c +++ b/kernel/time/timekeeping.c @@ -849,7 +849,7 @@ EXPORT_SYMBOL_GPL(ktime_get_real_seconds); #ifdef CONFIG_NTP_PPS /** - * getnstime_raw_and_real - get day and raw monotonic time in timespec format + * ktime_get_raw_and_real_ts64 - get day and raw monotonic time in timespec format * @ts_raw: pointer to the timespec to be set to raw monotonic time * @ts_real: pointer to the timespec to be set to the time of day * @@ -857,7 +857,7 @@ EXPORT_SYMBOL_GPL(ktime_get_real_seconds); * same time atomically and stores the resulting timestamps in timespec * format. */ -void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) +void ktime_get_raw_and_real_ts64(struct timespec64 *ts_raw, struct timespec64 *ts_real) { struct timekeeper *tk = &tk_core.timekeeper; unsigned long seq; @@ -868,7 +868,7 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) do { seq = read_seqcount_begin(&tk_core.seq); - *ts_raw = timespec64_to_timespec(tk->raw_time); + *ts_raw = tk->raw_time; ts_real->tv_sec = tk->xtime_sec; ts_real->tv_nsec = 0; @@ -877,10 +877,10 @@ void getnstime_raw_and_real(struct timespec *ts_raw, struct timespec *ts_real) } while (read_seqcount_retry(&tk_core.seq, seq)); - timespec_add_ns(ts_raw, nsecs_raw); - timespec_add_ns(ts_real, nsecs_real); + timespec64_add_ns(ts_raw, nsecs_raw); + timespec64_add_ns(ts_real, nsecs_real); } -EXPORT_SYMBOL(getnstime_raw_and_real); +EXPORT_SYMBOL(ktime_get_raw_and_real_ts64); #endif /* CONFIG_NTP_PPS */ @@ -1251,7 +1251,7 @@ void __init timekeeping_init(void) set_normalized_timespec64(&tmp, -boot.tv_sec, -boot.tv_nsec); tk_set_wall_to_mono(tk, tmp); - timekeeping_update(tk, TK_MIRROR); + timekeeping_update(tk, TK_MIRROR | TK_CLOCK_WAS_SET); write_seqcount_end(&tk_core.seq); raw_spin_unlock_irqrestore(&timekeeper_lock, flags); @@ -1614,7 +1614,7 @@ static __always_inline void timekeeping_freqadjust(struct timekeeper *tk, negative = (tick_error < 0); /* Sort out the magnitude of the correction */ - tick_error = abs64(tick_error); + tick_error = abs(tick_error); for (adj = 0; tick_error > interval; adj++) tick_error >>= 1; @@ -1674,7 +1674,7 @@ static void timekeeping_adjust(struct timekeeper *tk, s64 offset) /** * accumulate_nsecs_to_secs - Accumulates nsecs into secs * - * Helper function that accumulates a the nsecs greater then a second + * Helper function that accumulates the nsecs greater than a second * from the xtime_nsec field to the xtime_secs field. * It also calls into the NTP code to handle leapsecond processing. * @@ -1726,7 +1726,7 @@ static cycle_t logarithmic_accumulation(struct timekeeper *tk, cycle_t offset, cycle_t interval = tk->cycle_interval << shift; u64 raw_nsecs; - /* If the offset is smaller then a shifted interval, do nothing */ + /* If the offset is smaller than a shifted interval, do nothing */ if (offset < interval) return offset; @@ -2025,7 +2025,7 @@ int do_adjtimex(struct timex *txc) /** * hardpps() - Accessor function to NTP __hardpps function */ -void hardpps(const struct timespec *phase_ts, const struct timespec *raw_ts) +void hardpps(const struct timespec64 *phase_ts, const struct timespec64 *raw_ts) { unsigned long flags; diff --git a/kernel/time/timer.c b/kernel/time/timer.c index 84190f02b521..74591ba9474f 100644 --- a/kernel/time/timer.c +++ b/kernel/time/timer.c @@ -461,10 +461,17 @@ void __timer_stats_timer_set_start_info(struct timer_list *timer, void *addr) static void timer_stats_account_timer(struct timer_list *timer) { - if (likely(!timer->start_site)) + void *site; + + /* + * start_site can be concurrently reset by + * timer_stats_timer_clear_start_info() + */ + site = READ_ONCE(timer->start_site); + if (likely(!site)) return; - timer_stats_update_stats(timer, timer->start_pid, timer->start_site, + timer_stats_update_stats(timer, timer->start_pid, site, timer->function, timer->start_comm, timer->flags); } @@ -867,7 +874,7 @@ unsigned long apply_slack(struct timer_list *timer, unsigned long expires) if (mask == 0) return expires; - bit = find_last_bit(&mask, BITS_PER_LONG); + bit = __fls(mask); mask = (1UL << bit) - 1; diff --git a/kernel/torture.c b/kernel/torture.c index 3e4840633d3e..44aa462d033f 100644 --- a/kernel/torture.c +++ b/kernel/torture.c @@ -523,6 +523,7 @@ static int stutter; */ void stutter_wait(const char *title) { + cond_resched_rcu_qs(); while (READ_ONCE(stutter_pause_test) || (torture_runnable && !READ_ONCE(*torture_runnable))) { if (stutter_pause_test) diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig index 1153c43428f3..e45db6b0d878 100644 --- a/kernel/trace/Kconfig +++ b/kernel/trace/Kconfig @@ -434,7 +434,7 @@ config UPROBE_EVENT config BPF_EVENTS depends on BPF_SYSCALL - depends on KPROBE_EVENT || UPROBE_EVENT + depends on (KPROBE_EVENT || UPROBE_EVENT) && PERF_EVENTS bool default y help @@ -635,6 +635,13 @@ config TRACE_ENUM_MAP_FILE If unsure, say N +config TRACING_EVENTS_GPIO + bool "Trace gpio events" + depends on GPIOLIB + default y + help + Enable tracing events for gpio subsystem + endif # FTRACE endif # TRACING_SUPPORT diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c index 90e72a0c3047..a990824c8604 100644 --- a/kernel/trace/blktrace.c +++ b/kernel/trace/blktrace.c @@ -103,7 +103,7 @@ record_it: memcpy((void *) t + sizeof(*t), data, len); if (blk_tracer) - trace_buffer_unlock_commit(buffer, event, 0, pc); + trace_buffer_unlock_commit(blk_tr, buffer, event, 0, pc); } } @@ -278,7 +278,7 @@ record_it: memcpy((void *) t + sizeof(*t), pdu_data, pdu_len); if (blk_tracer) { - trace_buffer_unlock_commit(buffer, event, 0, pc); + trace_buffer_unlock_commit(blk_tr, buffer, event, 0, pc); return; } } @@ -437,7 +437,7 @@ int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, struct block_device *bdev, struct blk_user_trace_setup *buts) { - struct blk_trace *old_bt, *bt = NULL; + struct blk_trace *bt = NULL; struct dentry *dir = NULL; int ret; @@ -519,11 +519,8 @@ int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, bt->trace_state = Blktrace_setup; ret = -EBUSY; - old_bt = xchg(&q->blk_trace, bt); - if (old_bt) { - (void) xchg(&q->blk_trace, old_bt); + if (cmpxchg(&q->blk_trace, NULL, bt)) goto err; - } if (atomic_inc_return(&blk_probes_ref) == 1) blk_register_tracepoints(); @@ -1343,6 +1340,7 @@ static const struct { static enum print_line_t print_one_line(struct trace_iterator *iter, bool classic) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; const struct blk_io_trace *t; u16 what; @@ -1351,7 +1349,7 @@ static enum print_line_t print_one_line(struct trace_iterator *iter, t = te_blk_io_trace(iter->ent); what = t->action & ((1 << BLK_TC_SHIFT) - 1); - long_act = !!(trace_flags & TRACE_ITER_VERBOSE); + long_act = !!(tr->trace_flags & TRACE_ITER_VERBOSE); log_action = classic ? &blk_log_action_classic : &blk_log_action; if (t->action == BLK_TN_MESSAGE) { @@ -1413,9 +1411,9 @@ blk_tracer_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) /* don't output context-info for blk_classic output */ if (bit == TRACE_BLK_OPT_CLASSIC) { if (set) - trace_flags &= ~TRACE_ITER_CONTEXT_INFO; + tr->trace_flags &= ~TRACE_ITER_CONTEXT_INFO; else - trace_flags |= TRACE_ITER_CONTEXT_INFO; + tr->trace_flags |= TRACE_ITER_CONTEXT_INFO; } return 0; } @@ -1481,7 +1479,7 @@ static int blk_trace_remove_queue(struct request_queue *q) static int blk_trace_setup_queue(struct request_queue *q, struct block_device *bdev) { - struct blk_trace *old_bt, *bt = NULL; + struct blk_trace *bt = NULL; int ret = -ENOMEM; bt = kzalloc(sizeof(*bt), GFP_KERNEL); @@ -1497,12 +1495,9 @@ static int blk_trace_setup_queue(struct request_queue *q, blk_trace_setup_lba(bt, bdev); - old_bt = xchg(&q->blk_trace, bt); - if (old_bt != NULL) { - (void)xchg(&q->blk_trace, old_bt); - ret = -EBUSY; + ret = -EBUSY; + if (cmpxchg(&q->blk_trace, NULL, bt)) goto free_bt; - } if (atomic_inc_return(&blk_probes_ref) == 1) blk_register_tracepoints(); diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 0fe96c7c8803..4228fd3682c3 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -199,6 +199,11 @@ static u64 bpf_perf_event_read(u64 r1, u64 index, u64 r3, u64 r4, u64 r5) if (!event) return -ENOENT; + /* make sure event is local and doesn't have pmu::count */ + if (event->oncpu != smp_processor_id() || + event->pmu->count) + return -EINVAL; + /* * we don't know if the function is run successfully by the * return value. It can be judged in other places, such as @@ -207,14 +212,58 @@ static u64 bpf_perf_event_read(u64 r1, u64 index, u64 r3, u64 r4, u64 r5) return perf_event_read_local(event); } -const struct bpf_func_proto bpf_perf_event_read_proto = { +static const struct bpf_func_proto bpf_perf_event_read_proto = { .func = bpf_perf_event_read, - .gpl_only = false, + .gpl_only = true, .ret_type = RET_INTEGER, .arg1_type = ARG_CONST_MAP_PTR, .arg2_type = ARG_ANYTHING, }; +static u64 bpf_perf_event_output(u64 r1, u64 r2, u64 index, u64 r4, u64 size) +{ + struct pt_regs *regs = (struct pt_regs *) (long) r1; + struct bpf_map *map = (struct bpf_map *) (long) r2; + struct bpf_array *array = container_of(map, struct bpf_array, map); + void *data = (void *) (long) r4; + struct perf_sample_data sample_data; + struct perf_event *event; + struct perf_raw_record raw = { + .size = size, + .data = data, + }; + + if (unlikely(index >= array->map.max_entries)) + return -E2BIG; + + event = (struct perf_event *)array->ptrs[index]; + if (unlikely(!event)) + return -ENOENT; + + if (unlikely(event->attr.type != PERF_TYPE_SOFTWARE || + event->attr.config != PERF_COUNT_SW_BPF_OUTPUT)) + return -EINVAL; + + if (unlikely(event->oncpu != smp_processor_id())) + return -EOPNOTSUPP; + + perf_sample_data_init(&sample_data, 0, 0); + sample_data.raw = &raw; + perf_event_output(event, &sample_data, regs); + return 0; +} + +static const struct bpf_func_proto bpf_perf_event_output_proto = { + .func = bpf_perf_event_output, + .gpl_only = true, + .ret_type = RET_INTEGER, + .arg1_type = ARG_PTR_TO_CTX, + .arg2_type = ARG_CONST_MAP_PTR, + .arg3_type = ARG_ANYTHING, + .arg4_type = ARG_PTR_TO_STACK, + .arg5_type = ARG_CONST_STACK_SIZE, +}; + static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func_id) { switch (func_id) { @@ -242,6 +291,8 @@ static const struct bpf_func_proto *kprobe_prog_func_proto(enum bpf_func_id func return &bpf_get_smp_processor_id_proto; case BPF_FUNC_perf_event_read: return &bpf_perf_event_read_proto; + case BPF_FUNC_perf_event_output: + return &bpf_perf_event_output_proto; default: return NULL; } diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index b0623ac785a2..3f743b147247 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -243,6 +243,11 @@ static void ftrace_sync_ipi(void *data) #ifdef CONFIG_FUNCTION_GRAPH_TRACER static void update_function_graph_func(void); + +/* Both enabled by default (can be cleared by function_graph tracer flags */ +static bool fgraph_sleep_time = true; +static bool fgraph_graph_time = true; + #else static inline void update_function_graph_func(void) { } #endif @@ -917,7 +922,7 @@ static void profile_graph_return(struct ftrace_graph_ret *trace) calltime = trace->rettime - trace->calltime; - if (!(trace_flags & TRACE_ITER_GRAPH_TIME)) { + if (!fgraph_graph_time) { int index; index = trace->depth; @@ -3420,27 +3425,35 @@ ftrace_notrace_open(struct inode *inode, struct file *file) inode, file); } -static int ftrace_match(char *str, char *regex, int len, int type) +/* Type for quick search ftrace basic regexes (globs) from filter_parse_regex */ +struct ftrace_glob { + char *search; + unsigned len; + int type; +}; + +static int ftrace_match(char *str, struct ftrace_glob *g) { int matched = 0; int slen; - switch (type) { + switch (g->type) { case MATCH_FULL: - if (strcmp(str, regex) == 0) + if (strcmp(str, g->search) == 0) matched = 1; break; case MATCH_FRONT_ONLY: - if (strncmp(str, regex, len) == 0) + if (strncmp(str, g->search, g->len) == 0) matched = 1; break; case MATCH_MIDDLE_ONLY: - if (strstr(str, regex)) + if (strstr(str, g->search)) matched = 1; break; case MATCH_END_ONLY: slen = strlen(str); - if (slen >= len && memcmp(str + slen - len, regex, len) == 0) + if (slen >= g->len && + memcmp(str + slen - g->len, g->search, g->len) == 0) matched = 1; break; } @@ -3449,13 +3462,13 @@ static int ftrace_match(char *str, char *regex, int len, int type) } static int -enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) +enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int clear_filter) { struct ftrace_func_entry *entry; int ret = 0; entry = ftrace_lookup_ip(hash, rec->ip); - if (not) { + if (clear_filter) { /* Do nothing if it doesn't exist */ if (!entry) return 0; @@ -3472,42 +3485,68 @@ enter_record(struct ftrace_hash *hash, struct dyn_ftrace *rec, int not) } static int -ftrace_match_record(struct dyn_ftrace *rec, char *mod, - char *regex, int len, int type) +ftrace_match_record(struct dyn_ftrace *rec, struct ftrace_glob *func_g, + struct ftrace_glob *mod_g, int exclude_mod) { char str[KSYM_SYMBOL_LEN]; char *modname; kallsyms_lookup(rec->ip, NULL, NULL, &modname, str); - if (mod) { - /* module lookup requires matching the module */ - if (!modname || strcmp(modname, mod)) + if (mod_g) { + int mod_matches = (modname) ? ftrace_match(modname, mod_g) : 0; + + /* blank module name to match all modules */ + if (!mod_g->len) { + /* blank module globbing: modname xor exclude_mod */ + if ((!exclude_mod) != (!modname)) + goto func_match; + return 0; + } + + /* not matching the module */ + if (!modname || !mod_matches) { + if (exclude_mod) + goto func_match; + else + return 0; + } + + if (mod_matches && exclude_mod) return 0; +func_match: /* blank search means to match all funcs in the mod */ - if (!len) + if (!func_g->len) return 1; } - return ftrace_match(str, regex, len, type); + return ftrace_match(str, func_g); } static int -match_records(struct ftrace_hash *hash, char *buff, - int len, char *mod, int not) +match_records(struct ftrace_hash *hash, char *func, int len, char *mod) { - unsigned search_len = 0; struct ftrace_page *pg; struct dyn_ftrace *rec; - int type = MATCH_FULL; - char *search = buff; + struct ftrace_glob func_g = { .type = MATCH_FULL }; + struct ftrace_glob mod_g = { .type = MATCH_FULL }; + struct ftrace_glob *mod_match = (mod) ? &mod_g : NULL; + int exclude_mod = 0; int found = 0; int ret; + int clear_filter; + + if (func) { + func_g.type = filter_parse_regex(func, len, &func_g.search, + &clear_filter); + func_g.len = strlen(func_g.search); + } - if (len) { - type = filter_parse_regex(buff, len, &search, ¬); - search_len = strlen(search); + if (mod) { + mod_g.type = filter_parse_regex(mod, strlen(mod), + &mod_g.search, &exclude_mod); + mod_g.len = strlen(mod_g.search); } mutex_lock(&ftrace_lock); @@ -3516,8 +3555,8 @@ match_records(struct ftrace_hash *hash, char *buff, goto out_unlock; do_for_each_ftrace_rec(pg, rec) { - if (ftrace_match_record(rec, mod, search, search_len, type)) { - ret = enter_record(hash, rec, not); + if (ftrace_match_record(rec, &func_g, mod_match, exclude_mod)) { + ret = enter_record(hash, rec, clear_filter); if (ret < 0) { found = ret; goto out_unlock; @@ -3534,26 +3573,9 @@ match_records(struct ftrace_hash *hash, char *buff, static int ftrace_match_records(struct ftrace_hash *hash, char *buff, int len) { - return match_records(hash, buff, len, NULL, 0); + return match_records(hash, buff, len, NULL); } -static int -ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) -{ - int not = 0; - - /* blank or '*' mean the same */ - if (strcmp(buff, "*") == 0) - buff[0] = 0; - - /* handle the case of 'dont filter this module' */ - if (strcmp(buff, "!") == 0 || strcmp(buff, "!*") == 0) { - buff[0] = 0; - not = 1; - } - - return match_records(hash, buff, strlen(buff), mod, not); -} /* * We register the module command as a template to show others how @@ -3562,10 +3584,9 @@ ftrace_match_module_records(struct ftrace_hash *hash, char *buff, char *mod) static int ftrace_mod_callback(struct ftrace_hash *hash, - char *func, char *cmd, char *param, int enable) + char *func, char *cmd, char *module, int enable) { - char *mod; - int ret = -EINVAL; + int ret; /* * cmd == 'mod' because we only registered this func @@ -3574,21 +3595,11 @@ ftrace_mod_callback(struct ftrace_hash *hash, * you can tell which command was used by the cmd * parameter. */ - - /* we must have a module name */ - if (!param) - return ret; - - mod = strsep(¶m, ":"); - if (!strlen(mod)) - return ret; - - ret = ftrace_match_module_records(hash, func, mod); + ret = match_records(hash, func, strlen(func), module); if (!ret) - ret = -EINVAL; + return -EINVAL; if (ret < 0) return ret; - return 0; } @@ -3699,19 +3710,20 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, { struct ftrace_ops_hash old_hash_ops; struct ftrace_func_probe *entry; + struct ftrace_glob func_g; struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash; struct ftrace_hash *old_hash = *orig_hash; struct ftrace_hash *hash; struct ftrace_page *pg; struct dyn_ftrace *rec; - int type, len, not; + int not; unsigned long key; int count = 0; - char *search; int ret; - type = filter_parse_regex(glob, strlen(glob), &search, ¬); - len = strlen(search); + func_g.type = filter_parse_regex(glob, strlen(glob), + &func_g.search, ¬); + func_g.len = strlen(func_g.search); /* we do not support '!' for function probes */ if (WARN_ON(not)) @@ -3738,7 +3750,7 @@ register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, do_for_each_ftrace_rec(pg, rec) { - if (!ftrace_match_record(rec, NULL, search, len, type)) + if (!ftrace_match_record(rec, &func_g, NULL, 0)) continue; entry = kmalloc(sizeof(*entry), GFP_KERNEL); @@ -3811,24 +3823,24 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, struct ftrace_func_entry *rec_entry; struct ftrace_func_probe *entry; struct ftrace_func_probe *p; + struct ftrace_glob func_g; struct ftrace_hash **orig_hash = &trace_probe_ops.func_hash->filter_hash; struct ftrace_hash *old_hash = *orig_hash; struct list_head free_list; struct ftrace_hash *hash; struct hlist_node *tmp; char str[KSYM_SYMBOL_LEN]; - int type = MATCH_FULL; - int i, len = 0; - char *search; - int ret; + int i, ret; if (glob && (strcmp(glob, "*") == 0 || !strlen(glob))) - glob = NULL; + func_g.search = NULL; else if (glob) { int not; - type = filter_parse_regex(glob, strlen(glob), &search, ¬); - len = strlen(search); + func_g.type = filter_parse_regex(glob, strlen(glob), + &func_g.search, ¬); + func_g.len = strlen(func_g.search); + func_g.search = glob; /* we do not support '!' for function probes */ if (WARN_ON(not)) @@ -3857,10 +3869,10 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, continue; /* do this last, since it is the most expensive */ - if (glob) { + if (func_g.search) { kallsyms_lookup(entry->ip, NULL, NULL, NULL, str); - if (!ftrace_match(str, glob, len, type)) + if (!ftrace_match(str, &func_g)) continue; } @@ -3889,7 +3901,7 @@ __unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops, ftrace_free_entry(entry); } mutex_unlock(&ftrace_lock); - + out_unlock: mutex_unlock(&trace_probe_ops.func_hash->regex_lock); free_ftrace_hash(hash); @@ -4605,21 +4617,21 @@ ftrace_graph_release(struct inode *inode, struct file *file) static int ftrace_set_func(unsigned long *array, int *idx, int size, char *buffer) { + struct ftrace_glob func_g; struct dyn_ftrace *rec; struct ftrace_page *pg; - int search_len; int fail = 1; - int type, not; - char *search; + int not; bool exists; int i; /* decode regex */ - type = filter_parse_regex(buffer, strlen(buffer), &search, ¬); + func_g.type = filter_parse_regex(buffer, strlen(buffer), + &func_g.search, ¬); if (!not && *idx >= size) return -EBUSY; - search_len = strlen(search); + func_g.len = strlen(func_g.search); mutex_lock(&ftrace_lock); @@ -4630,7 +4642,7 @@ ftrace_set_func(unsigned long *array, int *idx, int size, char *buffer) do_for_each_ftrace_rec(pg, rec) { - if (ftrace_match_record(rec, NULL, search, search_len, type)) { + if (ftrace_match_record(rec, &func_g, NULL, 0)) { /* if it is in the array */ exists = false; for (i = 0; i < *idx; i++) { @@ -4783,17 +4795,6 @@ static int ftrace_cmp_ips(const void *a, const void *b) return 0; } -static void ftrace_swap_ips(void *a, void *b, int size) -{ - unsigned long *ipa = a; - unsigned long *ipb = b; - unsigned long t; - - t = *ipa; - *ipa = *ipb; - *ipb = t; -} - static int ftrace_process_locs(struct module *mod, unsigned long *start, unsigned long *end) @@ -4813,7 +4814,7 @@ static int ftrace_process_locs(struct module *mod, return 0; sort(start, count, sizeof(*start), - ftrace_cmp_ips, ftrace_swap_ips); + ftrace_cmp_ips, NULL); start_pg = ftrace_allocate_pages(count); if (!start_pg) @@ -5639,6 +5640,16 @@ static struct ftrace_ops graph_ops = { ASSIGN_OPS_HASH(graph_ops, &global_ops.local_hash) }; +void ftrace_graph_sleep_time_control(bool enable) +{ + fgraph_sleep_time = enable; +} + +void ftrace_graph_graph_time_control(bool enable) +{ + fgraph_graph_time = enable; +} + int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace) { return 0; @@ -5697,7 +5708,7 @@ free: } static void -ftrace_graph_probe_sched_switch(void *ignore, +ftrace_graph_probe_sched_switch(void *ignore, bool preempt, struct task_struct *prev, struct task_struct *next) { unsigned long long timestamp; @@ -5707,7 +5718,7 @@ ftrace_graph_probe_sched_switch(void *ignore, * Does the user want to count the time a function was asleep. * If so, do not update the time stamps. */ - if (trace_flags & TRACE_ITER_SLEEP_TIME) + if (fgraph_sleep_time) return; timestamp = trace_clock_local(); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index fc347f8b1bca..75f1d05ea82d 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -829,7 +829,7 @@ rb_is_head_page(struct ring_buffer_per_cpu *cpu_buffer, * writer is ever on it, the previous pointer never points * back to the reader page. */ -static int rb_is_reader_page(struct buffer_page *page) +static bool rb_is_reader_page(struct buffer_page *page) { struct list_head *list = page->list.prev; @@ -2270,7 +2270,7 @@ rb_add_time_stamp(struct ring_buffer_event *event, u64 delta) return skip_time_extend(event); } -static inline int rb_event_is_commit(struct ring_buffer_per_cpu *cpu_buffer, +static inline bool rb_event_is_commit(struct ring_buffer_per_cpu *cpu_buffer, struct ring_buffer_event *event); /** @@ -2498,7 +2498,7 @@ static inline void rb_event_discard(struct ring_buffer_event *event) event->time_delta = 1; } -static inline int +static inline bool rb_event_is_commit(struct ring_buffer_per_cpu *cpu_buffer, struct ring_buffer_event *event) { @@ -3039,7 +3039,7 @@ int ring_buffer_write(struct ring_buffer *buffer, } EXPORT_SYMBOL_GPL(ring_buffer_write); -static int rb_per_cpu_empty(struct ring_buffer_per_cpu *cpu_buffer) +static bool rb_per_cpu_empty(struct ring_buffer_per_cpu *cpu_buffer) { struct buffer_page *reader = cpu_buffer->reader_page; struct buffer_page *head = rb_set_head_page(cpu_buffer); @@ -3047,7 +3047,7 @@ static int rb_per_cpu_empty(struct ring_buffer_per_cpu *cpu_buffer) /* In case of error, head will be NULL */ if (unlikely(!head)) - return 1; + return true; return reader->read == rb_page_commit(reader) && (commit == reader || @@ -4267,7 +4267,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_reset); * rind_buffer_empty - is the ring buffer empty? * @buffer: The ring buffer to test */ -int ring_buffer_empty(struct ring_buffer *buffer) +bool ring_buffer_empty(struct ring_buffer *buffer) { struct ring_buffer_per_cpu *cpu_buffer; unsigned long flags; @@ -4285,10 +4285,10 @@ int ring_buffer_empty(struct ring_buffer *buffer) local_irq_restore(flags); if (!ret) - return 0; + return false; } - return 1; + return true; } EXPORT_SYMBOL_GPL(ring_buffer_empty); @@ -4297,7 +4297,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_empty); * @buffer: The ring buffer * @cpu: The CPU buffer to test */ -int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu) +bool ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; unsigned long flags; @@ -4305,7 +4305,7 @@ int ring_buffer_empty_cpu(struct ring_buffer *buffer, int cpu) int ret; if (!cpumask_test_cpu(cpu, buffer->cpumask)) - return 1; + return true; cpu_buffer = buffer->buffers[cpu]; local_irq_save(flags); diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c index a1503a027ee2..6df9a83e20d7 100644 --- a/kernel/trace/ring_buffer_benchmark.c +++ b/kernel/trace/ring_buffer_benchmark.c @@ -24,8 +24,8 @@ struct rb_page { static int wakeup_interval = 100; static int reader_finish; -static struct completion read_start; -static struct completion read_done; +static DECLARE_COMPLETION(read_start); +static DECLARE_COMPLETION(read_done); static struct ring_buffer *buffer; static struct task_struct *producer; @@ -60,12 +60,12 @@ MODULE_PARM_DESC(consumer_fifo, "fifo prio for consumer"); static int read_events; -static int kill_test; +static int test_error; -#define KILL_TEST() \ +#define TEST_ERROR() \ do { \ - if (!kill_test) { \ - kill_test = 1; \ + if (!test_error) { \ + test_error = 1; \ WARN_ON(1); \ } \ } while (0) @@ -75,6 +75,11 @@ enum event_status { EVENT_DROPPED, }; +static bool break_test(void) +{ + return test_error || kthread_should_stop(); +} + static enum event_status read_event(int cpu) { struct ring_buffer_event *event; @@ -87,7 +92,7 @@ static enum event_status read_event(int cpu) entry = ring_buffer_event_data(event); if (*entry != cpu) { - KILL_TEST(); + TEST_ERROR(); return EVENT_DROPPED; } @@ -115,10 +120,10 @@ static enum event_status read_page(int cpu) rpage = bpage; /* The commit may have missed event flags set, clear them */ commit = local_read(&rpage->commit) & 0xfffff; - for (i = 0; i < commit && !kill_test; i += inc) { + for (i = 0; i < commit && !test_error ; i += inc) { if (i >= (PAGE_SIZE - offsetof(struct rb_page, data))) { - KILL_TEST(); + TEST_ERROR(); break; } @@ -128,7 +133,7 @@ static enum event_status read_page(int cpu) case RINGBUF_TYPE_PADDING: /* failed writes may be discarded events */ if (!event->time_delta) - KILL_TEST(); + TEST_ERROR(); inc = event->array[0] + 4; break; case RINGBUF_TYPE_TIME_EXTEND: @@ -137,12 +142,12 @@ static enum event_status read_page(int cpu) case 0: entry = ring_buffer_event_data(event); if (*entry != cpu) { - KILL_TEST(); + TEST_ERROR(); break; } read++; if (!event->array[0]) { - KILL_TEST(); + TEST_ERROR(); break; } inc = event->array[0] + 4; @@ -150,17 +155,17 @@ static enum event_status read_page(int cpu) default: entry = ring_buffer_event_data(event); if (*entry != cpu) { - KILL_TEST(); + TEST_ERROR(); break; } read++; inc = ((event->type_len + 1) * 4); } - if (kill_test) + if (test_error) break; if (inc <= 0) { - KILL_TEST(); + TEST_ERROR(); break; } } @@ -178,10 +183,14 @@ static void ring_buffer_consumer(void) read_events ^= 1; read = 0; - while (!reader_finish && !kill_test) { - int found; + /* + * Continue running until the producer specifically asks to stop + * and is ready for the completion. + */ + while (!READ_ONCE(reader_finish)) { + int found = 1; - do { + while (found && !test_error) { int cpu; found = 0; @@ -193,19 +202,25 @@ static void ring_buffer_consumer(void) else stat = read_page(cpu); - if (kill_test) + if (test_error) break; + if (stat == EVENT_FOUND) found = 1; + } - } while (found && !kill_test); + } + /* Wait till the producer wakes us up when there is more data + * available or when the producer wants us to finish reading. + */ set_current_state(TASK_INTERRUPTIBLE); if (reader_finish) break; schedule(); } + __set_current_state(TASK_RUNNING); reader_finish = 0; complete(&read_done); } @@ -263,10 +278,7 @@ static void ring_buffer_producer(void) if (cnt % wakeup_interval) cond_resched(); #endif - if (kthread_should_stop()) - kill_test = 1; - - } while (ktime_before(end_time, timeout) && !kill_test); + } while (ktime_before(end_time, timeout) && !break_test()); trace_printk("End ring buffer hammer\n"); if (consumer) { @@ -276,8 +288,6 @@ static void ring_buffer_producer(void) /* the completions must be visible before the finish var */ smp_wmb(); reader_finish = 1; - /* finish var visible before waking up the consumer */ - smp_wmb(); wake_up_process(consumer); wait_for_completion(&read_done); } @@ -287,7 +297,7 @@ static void ring_buffer_producer(void) entries = ring_buffer_entries(buffer); overruns = ring_buffer_overruns(buffer); - if (kill_test && !kthread_should_stop()) + if (test_error) trace_printk("ERROR!\n"); if (!disable_reader) { @@ -368,15 +378,14 @@ static void wait_to_die(void) static int ring_buffer_consumer_thread(void *arg) { - while (!kthread_should_stop() && !kill_test) { + while (!break_test()) { complete(&read_start); ring_buffer_consumer(); set_current_state(TASK_INTERRUPTIBLE); - if (kthread_should_stop() || kill_test) + if (break_test()) break; - schedule(); } __set_current_state(TASK_RUNNING); @@ -389,27 +398,27 @@ static int ring_buffer_consumer_thread(void *arg) static int ring_buffer_producer_thread(void *arg) { - init_completion(&read_start); - - while (!kthread_should_stop() && !kill_test) { + while (!break_test()) { ring_buffer_reset(buffer); if (consumer) { - smp_wmb(); wake_up_process(consumer); wait_for_completion(&read_start); } ring_buffer_producer(); - if (kill_test) + if (break_test()) goto out_kill; trace_printk("Sleeping for 10 secs\n"); set_current_state(TASK_INTERRUPTIBLE); + if (break_test()) + goto out_kill; schedule_timeout(HZ * SLEEP_TIME); } out_kill: + __set_current_state(TASK_RUNNING); if (!kthread_should_stop()) wait_to_die(); diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 6e79408674aa..2198a630ef58 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -214,12 +214,10 @@ __setup("alloc_snapshot", boot_alloc_snapshot); static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; -static char *trace_boot_options __initdata; static int __init set_trace_boot_options(char *str) { strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); - trace_boot_options = trace_boot_options_buf; return 0; } __setup("trace_options=", set_trace_boot_options); @@ -250,6 +248,19 @@ unsigned long long ns2usecs(cycle_t nsec) return nsec; } +/* trace_flags holds trace_options default values */ +#define TRACE_DEFAULT_FLAGS \ + (FUNCTION_DEFAULT_FLAGS | \ + TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | \ + TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \ + TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \ + TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS) + +/* trace_options that are only supported by global_trace */ +#define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \ + TRACE_ITER_PRINTK_MSGONLY | TRACE_ITER_RECORD_CMD) + + /* * The global_trace is the descriptor that holds the tracing * buffers for the live tracing. For each CPU, it contains @@ -262,7 +273,9 @@ unsigned long long ns2usecs(cycle_t nsec) * pages for the buffer for that CPU. Each CPU has the same number * of pages allocated for its buffer. */ -static struct trace_array global_trace; +static struct trace_array global_trace = { + .trace_flags = TRACE_DEFAULT_FLAGS, +}; LIST_HEAD(ftrace_trace_arrays); @@ -468,11 +481,29 @@ static inline void trace_access_lock_init(void) #endif -/* trace_flags holds trace_options default values */ -unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | - TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME | - TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | - TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | TRACE_ITER_FUNCTION; +#ifdef CONFIG_STACKTRACE +static void __ftrace_trace_stack(struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs); +static inline void ftrace_trace_stack(struct trace_array *tr, + struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs); + +#else +static inline void __ftrace_trace_stack(struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs) +{ +} +static inline void ftrace_trace_stack(struct trace_array *tr, + struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs) +{ +} + +#endif static void tracer_tracing_on(struct trace_array *tr) { @@ -518,7 +549,7 @@ int __trace_puts(unsigned long ip, const char *str, int size) int alloc; int pc; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) return 0; pc = preempt_count(); @@ -548,7 +579,7 @@ int __trace_puts(unsigned long ip, const char *str, int size) entry->buf[size] = '\0'; __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(buffer, irq_flags, 4, pc); + ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); return size; } @@ -568,7 +599,7 @@ int __trace_bputs(unsigned long ip, const char *str) int size = sizeof(struct bputs_entry); int pc; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) return 0; pc = preempt_count(); @@ -588,7 +619,7 @@ int __trace_bputs(unsigned long ip, const char *str) entry->str = str; __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(buffer, irq_flags, 4, pc); + ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); return 1; } @@ -834,34 +865,18 @@ unsigned long nsecs_to_usecs(unsigned long nsecs) return nsecs / 1000; } +/* + * TRACE_FLAGS is defined as a tuple matching bit masks with strings. + * It uses C(a, b) where 'a' is the enum name and 'b' is the string that + * matches it. By defining "C(a, b) b", TRACE_FLAGS becomes a list + * of strings in the order that the enums were defined. + */ +#undef C +#define C(a, b) b + /* These must match the bit postions in trace_iterator_flags */ static const char *trace_options[] = { - "print-parent", - "sym-offset", - "sym-addr", - "verbose", - "raw", - "hex", - "bin", - "block", - "stacktrace", - "trace_printk", - "ftrace_preempt", - "branch", - "annotate", - "userstacktrace", - "sym-userobj", - "printk-msg-only", - "context-info", - "latency-format", - "sleep-time", - "graph-time", - "record-cmd", - "overwrite", - "disable_on_free", - "irq-info", - "markers", - "function-trace", + TRACE_FLAGS NULL }; @@ -1204,13 +1219,17 @@ static inline int run_tracer_selftest(struct tracer *type) } #endif /* CONFIG_FTRACE_STARTUP_TEST */ +static void add_tracer_options(struct trace_array *tr, struct tracer *t); + +static void __init apply_trace_boot_options(void); + /** * register_tracer - register a tracer with the ftrace system. * @type - the plugin for the tracer * * Register a new plugin tracer. */ -int register_tracer(struct tracer *type) +int __init register_tracer(struct tracer *type) { struct tracer *t; int ret = 0; @@ -1253,6 +1272,7 @@ int register_tracer(struct tracer *type) type->next = trace_types; trace_types = type; + add_tracer_options(&global_trace, type); out: tracing_selftest_running = false; @@ -1268,6 +1288,9 @@ int register_tracer(struct tracer *type) /* Do we want this tracer to start on bootup? */ tracing_set_tracer(&global_trace, type->name); default_bootup_tracer = NULL; + + apply_trace_boot_options(); + /* disable other selftests, since this will break it. */ tracing_selftest_disabled = true; #ifdef CONFIG_FTRACE_STARTUP_TEST @@ -1671,23 +1694,16 @@ __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *eve ring_buffer_unlock_commit(buffer, event); } -static inline void -__trace_buffer_unlock_commit(struct ring_buffer *buffer, - struct ring_buffer_event *event, - unsigned long flags, int pc) +void trace_buffer_unlock_commit(struct trace_array *tr, + struct ring_buffer *buffer, + struct ring_buffer_event *event, + unsigned long flags, int pc) { __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(buffer, flags, 6, pc); + ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL); ftrace_trace_userstack(buffer, flags, pc); } - -void trace_buffer_unlock_commit(struct ring_buffer *buffer, - struct ring_buffer_event *event, - unsigned long flags, int pc) -{ - __trace_buffer_unlock_commit(buffer, event, flags, pc); -} EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); static struct ring_buffer *temp_buffer; @@ -1729,22 +1745,15 @@ trace_current_buffer_lock_reserve(struct ring_buffer **current_rb, } EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve); -void trace_current_buffer_unlock_commit(struct ring_buffer *buffer, - struct ring_buffer_event *event, - unsigned long flags, int pc) -{ - __trace_buffer_unlock_commit(buffer, event, flags, pc); -} -EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit); - -void trace_buffer_unlock_commit_regs(struct ring_buffer *buffer, +void trace_buffer_unlock_commit_regs(struct trace_array *tr, + struct ring_buffer *buffer, struct ring_buffer_event *event, unsigned long flags, int pc, struct pt_regs *regs) { __buffer_unlock_commit(buffer, event); - ftrace_trace_stack_regs(buffer, flags, 0, pc, regs); + ftrace_trace_stack(tr, buffer, flags, 6, pc, regs); ftrace_trace_userstack(buffer, flags, pc); } EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit_regs); @@ -1873,24 +1882,17 @@ static void __ftrace_trace_stack(struct ring_buffer *buffer, } -void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, - int skip, int pc, struct pt_regs *regs) +static inline void ftrace_trace_stack(struct trace_array *tr, + struct ring_buffer *buffer, + unsigned long flags, + int skip, int pc, struct pt_regs *regs) { - if (!(trace_flags & TRACE_ITER_STACKTRACE)) + if (!(tr->trace_flags & TRACE_ITER_STACKTRACE)) return; __ftrace_trace_stack(buffer, flags, skip, pc, regs); } -void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, - int skip, int pc) -{ - if (!(trace_flags & TRACE_ITER_STACKTRACE)) - return; - - __ftrace_trace_stack(buffer, flags, skip, pc, NULL); -} - void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, int pc) { @@ -1929,7 +1931,7 @@ ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) struct userstack_entry *entry; struct stack_trace trace; - if (!(trace_flags & TRACE_ITER_USERSTACKTRACE)) + if (!(global_trace.trace_flags & TRACE_ITER_USERSTACKTRACE)) return; /* @@ -2173,7 +2175,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) memcpy(entry->buf, tbuffer, sizeof(u32) * len); if (!call_filter_check_discard(call, entry, buffer, event)) { __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(buffer, flags, 6, pc); + ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL); } out: @@ -2225,7 +2227,7 @@ __trace_array_vprintk(struct ring_buffer *buffer, memcpy(&entry->buf, tbuffer, len + 1); if (!call_filter_check_discard(call, entry, buffer, event)) { __buffer_unlock_commit(buffer, event); - ftrace_trace_stack(buffer, flags, 6, pc); + ftrace_trace_stack(&global_trace, buffer, flags, 6, pc, NULL); } out: preempt_enable_notrace(); @@ -2246,7 +2248,7 @@ int trace_array_printk(struct trace_array *tr, int ret; va_list ap; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) return 0; va_start(ap, fmt); @@ -2261,7 +2263,7 @@ int trace_array_printk_buf(struct ring_buffer *buffer, int ret; va_list ap; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) return 0; va_start(ap, fmt); @@ -2602,7 +2604,7 @@ static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file void print_trace_header(struct seq_file *m, struct trace_iterator *iter) { - unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); + unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK); struct trace_buffer *buf = iter->trace_buffer; struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); struct tracer *type = iter->trace; @@ -2664,20 +2666,22 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter) static void test_cpu_buff_start(struct trace_iterator *iter) { struct trace_seq *s = &iter->seq; + struct trace_array *tr = iter->tr; - if (!(trace_flags & TRACE_ITER_ANNOTATE)) + if (!(tr->trace_flags & TRACE_ITER_ANNOTATE)) return; if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) return; - if (cpumask_test_cpu(iter->cpu, iter->started)) + if (iter->started && cpumask_test_cpu(iter->cpu, iter->started)) return; if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) return; - cpumask_set_cpu(iter->cpu, iter->started); + if (iter->started) + cpumask_set_cpu(iter->cpu, iter->started); /* Don't print started cpu buffer for the first entry of the trace */ if (iter->idx > 1) @@ -2687,8 +2691,9 @@ static void test_cpu_buff_start(struct trace_iterator *iter) static enum print_line_t print_trace_fmt(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; - unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); + unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK); struct trace_entry *entry; struct trace_event *event; @@ -2698,7 +2703,7 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter) event = ftrace_find_event(entry->type); - if (trace_flags & TRACE_ITER_CONTEXT_INFO) { + if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { if (iter->iter_flags & TRACE_FILE_LAT_FMT) trace_print_lat_context(iter); else @@ -2718,13 +2723,14 @@ static enum print_line_t print_trace_fmt(struct trace_iterator *iter) static enum print_line_t print_raw_fmt(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; struct trace_entry *entry; struct trace_event *event; entry = iter->ent; - if (trace_flags & TRACE_ITER_CONTEXT_INFO) + if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) trace_seq_printf(s, "%d %d %llu ", entry->pid, iter->cpu, iter->ts); @@ -2742,6 +2748,7 @@ static enum print_line_t print_raw_fmt(struct trace_iterator *iter) static enum print_line_t print_hex_fmt(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; unsigned char newline = '\n'; struct trace_entry *entry; @@ -2749,7 +2756,7 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter) entry = iter->ent; - if (trace_flags & TRACE_ITER_CONTEXT_INFO) { + if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { SEQ_PUT_HEX_FIELD(s, entry->pid); SEQ_PUT_HEX_FIELD(s, iter->cpu); SEQ_PUT_HEX_FIELD(s, iter->ts); @@ -2771,13 +2778,14 @@ static enum print_line_t print_hex_fmt(struct trace_iterator *iter) static enum print_line_t print_bin_fmt(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; struct trace_entry *entry; struct trace_event *event; entry = iter->ent; - if (trace_flags & TRACE_ITER_CONTEXT_INFO) { + if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { SEQ_PUT_FIELD(s, entry->pid); SEQ_PUT_FIELD(s, iter->cpu); SEQ_PUT_FIELD(s, iter->ts); @@ -2826,6 +2834,8 @@ int trace_empty(struct trace_iterator *iter) /* Called with trace_event_read_lock() held. */ enum print_line_t print_trace_line(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; + unsigned long trace_flags = tr->trace_flags; enum print_line_t ret; if (iter->lost_events) { @@ -2871,6 +2881,7 @@ enum print_line_t print_trace_line(struct trace_iterator *iter) void trace_latency_header(struct seq_file *m) { struct trace_iterator *iter = m->private; + struct trace_array *tr = iter->tr; /* print nothing if the buffers are empty */ if (trace_empty(iter)) @@ -2879,13 +2890,15 @@ void trace_latency_header(struct seq_file *m) if (iter->iter_flags & TRACE_FILE_LAT_FMT) print_trace_header(m, iter); - if (!(trace_flags & TRACE_ITER_VERBOSE)) + if (!(tr->trace_flags & TRACE_ITER_VERBOSE)) print_lat_help_header(m); } void trace_default_header(struct seq_file *m) { struct trace_iterator *iter = m->private; + struct trace_array *tr = iter->tr; + unsigned long trace_flags = tr->trace_flags; if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) return; @@ -3230,7 +3243,7 @@ static int tracing_open(struct inode *inode, struct file *file) iter = __tracing_open(inode, file, false); if (IS_ERR(iter)) ret = PTR_ERR(iter); - else if (trace_flags & TRACE_ITER_LATENCY_FMT) + else if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) iter->iter_flags |= TRACE_FILE_LAT_FMT; } @@ -3477,7 +3490,7 @@ static int tracing_trace_options_show(struct seq_file *m, void *v) trace_opts = tr->current_trace->flags->opts; for (i = 0; trace_options[i]; i++) { - if (trace_flags & (1 << i)) + if (tr->trace_flags & (1 << i)) seq_printf(m, "%s\n", trace_options[i]); else seq_printf(m, "no%s\n", trace_options[i]); @@ -3542,7 +3555,7 @@ int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) { /* do nothing if flag is already set */ - if (!!(trace_flags & mask) == !!enabled) + if (!!(tr->trace_flags & mask) == !!enabled) return 0; /* Give the tracer a chance to approve the change */ @@ -3551,9 +3564,9 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) return -EINVAL; if (enabled) - trace_flags |= mask; + tr->trace_flags |= mask; else - trace_flags &= ~mask; + tr->trace_flags &= ~mask; if (mask == TRACE_ITER_RECORD_CMD) trace_event_enable_cmd_record(enabled); @@ -3565,8 +3578,10 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) #endif } - if (mask == TRACE_ITER_PRINTK) + if (mask == TRACE_ITER_PRINTK) { trace_printk_start_stop_comm(enabled); + trace_printk_control(enabled); + } return 0; } @@ -3577,6 +3592,7 @@ static int trace_set_options(struct trace_array *tr, char *option) int neg = 0; int ret = -ENODEV; int i; + size_t orig_len = strlen(option); cmp = strstrip(option); @@ -3600,9 +3616,36 @@ static int trace_set_options(struct trace_array *tr, char *option) mutex_unlock(&trace_types_lock); + /* + * If the first trailing whitespace is replaced with '\0' by strstrip, + * turn it back into a space. + */ + if (orig_len > strlen(option)) + option[strlen(option)] = ' '; + return ret; } +static void __init apply_trace_boot_options(void) +{ + char *buf = trace_boot_options_buf; + char *option; + + while (true) { + option = strsep(&buf, ","); + + if (!option) + break; + + if (*option) + trace_set_options(&global_trace, option); + + /* Put back the comma to allow this to be called again */ + if (buf) + *(buf - 1) = ','; + } +} + static ssize_t tracing_trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) @@ -4297,11 +4340,8 @@ int tracing_update_buffers(void) struct trace_option_dentry; -static struct trace_option_dentry * -create_trace_option_files(struct trace_array *tr, struct tracer *tracer); - static void -destroy_trace_option_files(struct trace_option_dentry *topts); +create_trace_option_files(struct trace_array *tr, struct tracer *tracer); /* * Used to clear out the tracer before deletion of an instance. @@ -4320,20 +4360,13 @@ static void tracing_set_nop(struct trace_array *tr) tr->current_trace = &nop_trace; } -static void update_tracer_options(struct trace_array *tr, struct tracer *t) +static void add_tracer_options(struct trace_array *tr, struct tracer *t) { - static struct trace_option_dentry *topts; - /* Only enable if the directory has been created already. */ if (!tr->dir) return; - /* Currently, only the top instance has options */ - if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL)) - return; - - destroy_trace_option_files(topts); - topts = create_trace_option_files(tr, t); + create_trace_option_files(tr, t); } static int tracing_set_tracer(struct trace_array *tr, const char *buf) @@ -4402,7 +4435,6 @@ static int tracing_set_tracer(struct trace_array *tr, const char *buf) free_snapshot(tr); } #endif - update_tracer_options(tr, t); #ifdef CONFIG_TRACER_MAX_TRACE if (t->use_max_tr && !had_max_tr) { @@ -4569,7 +4601,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) /* trace pipe does not show start of buffer */ cpumask_setall(iter->started); - if (trace_flags & TRACE_ITER_LATENCY_FMT) + if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) iter->iter_flags |= TRACE_FILE_LAT_FMT; /* Output in nanoseconds only if we are using a clock in nanoseconds. */ @@ -4626,11 +4658,13 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) static unsigned int trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) { + struct trace_array *tr = iter->tr; + /* Iterators are static, they should be filled or empty */ if (trace_buffer_iter(iter, iter->cpu_file)) return POLLIN | POLLRDNORM; - if (trace_flags & TRACE_ITER_BLOCK) + if (tr->trace_flags & TRACE_ITER_BLOCK) /* * Always select as readable when in blocking mode */ @@ -5047,7 +5081,7 @@ tracing_free_buffer_release(struct inode *inode, struct file *filp) struct trace_array *tr = inode->i_private; /* disable tracing ? */ - if (trace_flags & TRACE_ITER_STOP_ON_FREE) + if (tr->trace_flags & TRACE_ITER_STOP_ON_FREE) tracer_tracing_off(tr); /* resize the ring buffer to 0 */ tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); @@ -5080,7 +5114,7 @@ tracing_mark_write(struct file *filp, const char __user *ubuf, if (tracing_disabled) return -EINVAL; - if (!(trace_flags & TRACE_ITER_MARKERS)) + if (!(tr->trace_flags & TRACE_ITER_MARKERS)) return -EINVAL; if (cnt > TRACE_BUF_SIZE) @@ -6132,13 +6166,6 @@ tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) #include "trace_selftest.c" #endif -struct trace_option_dentry { - struct tracer_opt *opt; - struct tracer_flags *flags; - struct trace_array *tr; - struct dentry *entry; -}; - static ssize_t trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) @@ -6191,14 +6218,51 @@ static const struct file_operations trace_options_fops = { .llseek = generic_file_llseek, }; +/* + * In order to pass in both the trace_array descriptor as well as the index + * to the flag that the trace option file represents, the trace_array + * has a character array of trace_flags_index[], which holds the index + * of the bit for the flag it represents. index[0] == 0, index[1] == 1, etc. + * The address of this character array is passed to the flag option file + * read/write callbacks. + * + * In order to extract both the index and the trace_array descriptor, + * get_tr_index() uses the following algorithm. + * + * idx = *ptr; + * + * As the pointer itself contains the address of the index (remember + * index[1] == 1). + * + * Then to get the trace_array descriptor, by subtracting that index + * from the ptr, we get to the start of the index itself. + * + * ptr - idx == &index[0] + * + * Then a simple container_of() from that pointer gets us to the + * trace_array descriptor. + */ +static void get_tr_index(void *data, struct trace_array **ptr, + unsigned int *pindex) +{ + *pindex = *(unsigned char *)data; + + *ptr = container_of(data - *pindex, struct trace_array, + trace_flags_index); +} + static ssize_t trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) { - long index = (long)filp->private_data; + void *tr_index = filp->private_data; + struct trace_array *tr; + unsigned int index; char *buf; - if (trace_flags & (1 << index)) + get_tr_index(tr_index, &tr, &index); + + if (tr->trace_flags & (1 << index)) buf = "1\n"; else buf = "0\n"; @@ -6210,11 +6274,14 @@ static ssize_t trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) { - struct trace_array *tr = &global_trace; - long index = (long)filp->private_data; + void *tr_index = filp->private_data; + struct trace_array *tr; + unsigned int index; unsigned long val; int ret; + get_tr_index(tr_index, &tr, &index); + ret = kstrtoul_from_user(ubuf, cnt, 10, &val); if (ret) return ret; @@ -6298,21 +6365,39 @@ create_trace_option_file(struct trace_array *tr, } -static struct trace_option_dentry * +static void create_trace_option_files(struct trace_array *tr, struct tracer *tracer) { struct trace_option_dentry *topts; + struct trace_options *tr_topts; struct tracer_flags *flags; struct tracer_opt *opts; int cnt; + int i; if (!tracer) - return NULL; + return; flags = tracer->flags; if (!flags || !flags->opts) - return NULL; + return; + + /* + * If this is an instance, only create flags for tracers + * the instance may have. + */ + if (!trace_ok_for_array(tracer, tr)) + return; + + for (i = 0; i < tr->nr_topts; i++) { + /* + * Check if these flags have already been added. + * Some tracers share flags. + */ + if (tr->topts[i].tracer->flags == tracer->flags) + return; + } opts = flags->opts; @@ -6321,27 +6406,27 @@ create_trace_option_files(struct trace_array *tr, struct tracer *tracer) topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); if (!topts) - return NULL; - - for (cnt = 0; opts[cnt].name; cnt++) - create_trace_option_file(tr, &topts[cnt], flags, - &opts[cnt]); - - return topts; -} - -static void -destroy_trace_option_files(struct trace_option_dentry *topts) -{ - int cnt; + return; - if (!topts) + tr_topts = krealloc(tr->topts, sizeof(*tr->topts) * (tr->nr_topts + 1), + GFP_KERNEL); + if (!tr_topts) { + kfree(topts); return; + } - for (cnt = 0; topts[cnt].opt; cnt++) - tracefs_remove(topts[cnt].entry); + tr->topts = tr_topts; + tr->topts[tr->nr_topts].tracer = tracer; + tr->topts[tr->nr_topts].topts = topts; + tr->nr_topts++; - kfree(topts); + for (cnt = 0; opts[cnt].name; cnt++) { + create_trace_option_file(tr, &topts[cnt], flags, + &opts[cnt]); + WARN_ONCE(topts[cnt].entry == NULL, + "Failed to create trace option: %s", + opts[cnt].name); + } } static struct dentry * @@ -6354,21 +6439,26 @@ create_trace_option_core_file(struct trace_array *tr, if (!t_options) return NULL; - return trace_create_file(option, 0644, t_options, (void *)index, - &trace_options_core_fops); + return trace_create_file(option, 0644, t_options, + (void *)&tr->trace_flags_index[index], + &trace_options_core_fops); } -static __init void create_trace_options_dir(struct trace_array *tr) +static void create_trace_options_dir(struct trace_array *tr) { struct dentry *t_options; + bool top_level = tr == &global_trace; int i; t_options = trace_options_init_dentry(tr); if (!t_options) return; - for (i = 0; trace_options[i]; i++) - create_trace_option_core_file(tr, trace_options[i], i); + for (i = 0; trace_options[i]; i++) { + if (top_level || + !((1 << i) & TOP_LEVEL_TRACE_FLAGS)) + create_trace_option_core_file(tr, trace_options[i], i); + } } static ssize_t @@ -6435,7 +6525,7 @@ allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size { enum ring_buffer_flags rb_flags; - rb_flags = trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; + rb_flags = tr->trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; buf->tr = tr; @@ -6505,6 +6595,30 @@ static void free_trace_buffers(struct trace_array *tr) #endif } +static void init_trace_flags_index(struct trace_array *tr) +{ + int i; + + /* Used by the trace options files */ + for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) + tr->trace_flags_index[i] = i; +} + +static void __update_tracer_options(struct trace_array *tr) +{ + struct tracer *t; + + for (t = trace_types; t; t = t->next) + add_tracer_options(tr, t); +} + +static void update_tracer_options(struct trace_array *tr) +{ + mutex_lock(&trace_types_lock); + __update_tracer_options(tr); + mutex_unlock(&trace_types_lock); +} + static int instance_mkdir(const char *name) { struct trace_array *tr; @@ -6530,6 +6644,8 @@ static int instance_mkdir(const char *name) if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) goto out_free_tr; + tr->trace_flags = global_trace.trace_flags; + cpumask_copy(tr->tracing_cpumask, cpu_all_mask); raw_spin_lock_init(&tr->start_lock); @@ -6555,6 +6671,8 @@ static int instance_mkdir(const char *name) } init_tracer_tracefs(tr, tr->dir); + init_trace_flags_index(tr); + __update_tracer_options(tr); list_add(&tr->list, &ftrace_trace_arrays); @@ -6580,6 +6698,7 @@ static int instance_rmdir(const char *name) struct trace_array *tr; int found = 0; int ret; + int i; mutex_lock(&trace_types_lock); @@ -6602,9 +6721,14 @@ static int instance_rmdir(const char *name) tracing_set_nop(tr); event_trace_del_tracer(tr); ftrace_destroy_function_files(tr); - debugfs_remove_recursive(tr->dir); + tracefs_remove_recursive(tr->dir); free_trace_buffers(tr); + for (i = 0; i < tr->nr_topts; i++) { + kfree(tr->topts[i].topts); + } + kfree(tr->topts); + kfree(tr->name); kfree(tr); @@ -6666,6 +6790,8 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) trace_create_file("tracing_on", 0644, d_tracer, tr, &rb_simple_fops); + create_trace_options_dir(tr); + #ifdef CONFIG_TRACER_MAX_TRACE trace_create_file("tracing_max_latency", 0644, d_tracer, &tr->max_latency, &tracing_max_lat_fops); @@ -6861,11 +6987,7 @@ static __init int tracer_init_tracefs(void) create_trace_instances(d_tracer); - create_trace_options_dir(&global_trace); - - /* If the tracer was started via cmdline, create options for it here */ - if (global_trace.current_trace != &nop_trace) - update_tracer_options(&global_trace, global_trace.current_trace); + update_tracer_options(&global_trace); return 0; } @@ -6964,6 +7086,7 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) /* use static because iter can be a bit big for the stack */ static struct trace_iterator iter; static atomic_t dump_running; + struct trace_array *tr = &global_trace; unsigned int old_userobj; unsigned long flags; int cnt = 0, cpu; @@ -6993,10 +7116,10 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); } - old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ; + old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ; /* don't look at user memory in panic mode */ - trace_flags &= ~TRACE_ITER_SYM_USEROBJ; + tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ; switch (oops_dump_mode) { case DUMP_ALL: @@ -7059,7 +7182,7 @@ void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) printk(KERN_TRACE "---------------------------------\n"); out_enable: - trace_flags |= old_userobj; + tr->trace_flags |= old_userobj; for_each_tracing_cpu(cpu) { atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); @@ -7074,6 +7197,12 @@ __init static int tracer_alloc_buffers(void) int ring_buf_size; int ret = -ENOMEM; + /* + * Make sure we don't accidently add more trace options + * than we have bits for. + */ + BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE); + if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) goto out; @@ -7132,6 +7261,8 @@ __init static int tracer_alloc_buffers(void) ftrace_init_global_array_ops(&global_trace); + init_trace_flags_index(&global_trace); + register_tracer(&nop_trace); /* All seems OK, enable tracing */ @@ -7148,12 +7279,7 @@ __init static int tracer_alloc_buffers(void) INIT_LIST_HEAD(&global_trace.events); list_add(&global_trace.list, &ftrace_trace_arrays); - while (trace_boot_options) { - char *option; - - option = strsep(&trace_boot_options, ","); - trace_set_options(&global_trace, option); - } + apply_trace_boot_options(); register_snapshot_cmd(); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 74bde81601a9..dd7620802e72 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -71,9 +71,6 @@ enum trace_type { tstruct \ } -#undef TP_ARGS -#define TP_ARGS(args...) args - #undef FTRACE_ENTRY_DUP #define FTRACE_ENTRY_DUP(name, name_struct, id, tstruct, printk, filter) @@ -156,9 +153,12 @@ struct trace_array_cpu { pid_t pid; kuid_t uid; char comm[TASK_COMM_LEN]; + + bool ignore_pid; }; struct tracer; +struct trace_option_dentry; struct trace_buffer { struct trace_array *tr; @@ -168,6 +168,19 @@ struct trace_buffer { int cpu; }; +#define TRACE_FLAGS_MAX_SIZE 32 + +struct trace_options { + struct tracer *tracer; + struct trace_option_dentry *topts; +}; + +struct trace_pid_list { + unsigned int nr_pids; + int order; + pid_t *pids; +}; + /* * The trace array - an array of per-CPU trace arrays. This is the * highest level data structure that individual tracers deal with. @@ -193,6 +206,7 @@ struct trace_array { bool allocated_snapshot; unsigned long max_latency; #endif + struct trace_pid_list __rcu *filtered_pids; /* * max_lock is used to protect the swapping of buffers * when taking a max snapshot. The buffers themselves are @@ -216,13 +230,17 @@ struct trace_array { #endif int stop_count; int clock_id; + int nr_topts; struct tracer *current_trace; + unsigned int trace_flags; + unsigned char trace_flags_index[TRACE_FLAGS_MAX_SIZE]; unsigned int flags; raw_spinlock_t start_lock; struct dentry *dir; struct dentry *options; struct dentry *percpu_dir; struct dentry *event_dir; + struct trace_options *topts; struct list_head systems; struct list_head events; cpumask_var_t tracing_cpumask; /* only trace on set CPUs */ @@ -333,6 +351,13 @@ struct tracer_flags { #define TRACER_OPT(s, b) .name = #s, .bit = b +struct trace_option_dentry { + struct tracer_opt *opt; + struct tracer_flags *flags; + struct trace_array *tr; + struct dentry *entry; +}; + /** * struct tracer - a specific tracer and its callbacks to interact with tracefs * @name: the name chosen to select it on the available_tracers file @@ -611,29 +636,12 @@ void update_max_tr_single(struct trace_array *tr, #endif /* CONFIG_TRACER_MAX_TRACE */ #ifdef CONFIG_STACKTRACE -void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags, - int skip, int pc); - -void ftrace_trace_stack_regs(struct ring_buffer *buffer, unsigned long flags, - int skip, int pc, struct pt_regs *regs); - void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc); void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, int pc); #else -static inline void ftrace_trace_stack(struct ring_buffer *buffer, - unsigned long flags, int skip, int pc) -{ -} - -static inline void ftrace_trace_stack_regs(struct ring_buffer *buffer, - unsigned long flags, int skip, - int pc, struct pt_regs *regs) -{ -} - static inline void ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) { @@ -707,8 +715,6 @@ int trace_array_printk_buf(struct ring_buffer *buffer, void trace_printk_seq(struct trace_seq *s); enum print_line_t print_trace_line(struct trace_iterator *iter); -extern unsigned long trace_flags; - extern char trace_find_mark(unsigned long long duration); /* Standard output formatting function used for function return traces */ @@ -723,9 +729,14 @@ extern char trace_find_mark(unsigned long long duration); #define TRACE_GRAPH_PRINT_ABS_TIME 0x20 #define TRACE_GRAPH_PRINT_IRQS 0x40 #define TRACE_GRAPH_PRINT_TAIL 0x80 +#define TRACE_GRAPH_SLEEP_TIME 0x100 +#define TRACE_GRAPH_GRAPH_TIME 0x200 #define TRACE_GRAPH_PRINT_FILL_SHIFT 28 #define TRACE_GRAPH_PRINT_FILL_MASK (0x3 << TRACE_GRAPH_PRINT_FILL_SHIFT) +extern void ftrace_graph_sleep_time_control(bool enable); +extern void ftrace_graph_graph_time_control(bool enable); + extern enum print_line_t print_graph_function_flags(struct trace_iterator *iter, u32 flags); extern void print_graph_headers_flags(struct seq_file *s, u32 flags); @@ -859,7 +870,7 @@ void ftrace_destroy_filter_files(struct ftrace_ops *ops); #define ftrace_destroy_filter_files(ops) do { } while (0) #endif /* CONFIG_FUNCTION_TRACER && CONFIG_DYNAMIC_FTRACE */ -int ftrace_event_is_function(struct trace_event_call *call); +bool ftrace_event_is_function(struct trace_event_call *call); /* * struct trace_parser - servers for reading the user input separated by spaces @@ -897,42 +908,94 @@ extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf, size_t cnt, loff_t *ppos); /* + * Only create function graph options if function graph is configured. + */ +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +# define FGRAPH_FLAGS \ + C(DISPLAY_GRAPH, "display-graph"), +#else +# define FGRAPH_FLAGS +#endif + +#ifdef CONFIG_BRANCH_TRACER +# define BRANCH_FLAGS \ + C(BRANCH, "branch"), +#else +# define BRANCH_FLAGS +#endif + +#ifdef CONFIG_FUNCTION_TRACER +# define FUNCTION_FLAGS \ + C(FUNCTION, "function-trace"), +# define FUNCTION_DEFAULT_FLAGS TRACE_ITER_FUNCTION +#else +# define FUNCTION_FLAGS +# define FUNCTION_DEFAULT_FLAGS 0UL +#endif + +#ifdef CONFIG_STACKTRACE +# define STACK_FLAGS \ + C(STACKTRACE, "stacktrace"), +#else +# define STACK_FLAGS +#endif + +/* * trace_iterator_flags is an enumeration that defines bit * positions into trace_flags that controls the output. * * NOTE: These bits must match the trace_options array in - * trace.c. + * trace.c (this macro guarantees it). + */ +#define TRACE_FLAGS \ + C(PRINT_PARENT, "print-parent"), \ + C(SYM_OFFSET, "sym-offset"), \ + C(SYM_ADDR, "sym-addr"), \ + C(VERBOSE, "verbose"), \ + C(RAW, "raw"), \ + C(HEX, "hex"), \ + C(BIN, "bin"), \ + C(BLOCK, "block"), \ + C(PRINTK, "trace_printk"), \ + C(ANNOTATE, "annotate"), \ + C(USERSTACKTRACE, "userstacktrace"), \ + C(SYM_USEROBJ, "sym-userobj"), \ + C(PRINTK_MSGONLY, "printk-msg-only"), \ + C(CONTEXT_INFO, "context-info"), /* Print pid/cpu/time */ \ + C(LATENCY_FMT, "latency-format"), \ + C(RECORD_CMD, "record-cmd"), \ + C(OVERWRITE, "overwrite"), \ + C(STOP_ON_FREE, "disable_on_free"), \ + C(IRQ_INFO, "irq-info"), \ + C(MARKERS, "markers"), \ + FUNCTION_FLAGS \ + FGRAPH_FLAGS \ + STACK_FLAGS \ + BRANCH_FLAGS + +/* + * By defining C, we can make TRACE_FLAGS a list of bit names + * that will define the bits for the flag masks. */ -enum trace_iterator_flags { - TRACE_ITER_PRINT_PARENT = 0x01, - TRACE_ITER_SYM_OFFSET = 0x02, - TRACE_ITER_SYM_ADDR = 0x04, - TRACE_ITER_VERBOSE = 0x08, - TRACE_ITER_RAW = 0x10, - TRACE_ITER_HEX = 0x20, - TRACE_ITER_BIN = 0x40, - TRACE_ITER_BLOCK = 0x80, - TRACE_ITER_STACKTRACE = 0x100, - TRACE_ITER_PRINTK = 0x200, - TRACE_ITER_PREEMPTONLY = 0x400, - TRACE_ITER_BRANCH = 0x800, - TRACE_ITER_ANNOTATE = 0x1000, - TRACE_ITER_USERSTACKTRACE = 0x2000, - TRACE_ITER_SYM_USEROBJ = 0x4000, - TRACE_ITER_PRINTK_MSGONLY = 0x8000, - TRACE_ITER_CONTEXT_INFO = 0x10000, /* Print pid/cpu/time */ - TRACE_ITER_LATENCY_FMT = 0x20000, - TRACE_ITER_SLEEP_TIME = 0x40000, - TRACE_ITER_GRAPH_TIME = 0x80000, - TRACE_ITER_RECORD_CMD = 0x100000, - TRACE_ITER_OVERWRITE = 0x200000, - TRACE_ITER_STOP_ON_FREE = 0x400000, - TRACE_ITER_IRQ_INFO = 0x800000, - TRACE_ITER_MARKERS = 0x1000000, - TRACE_ITER_FUNCTION = 0x2000000, +#undef C +#define C(a, b) TRACE_ITER_##a##_BIT + +enum trace_iterator_bits { + TRACE_FLAGS + /* Make sure we don't go more than we have bits for */ + TRACE_ITER_LAST_BIT }; /* + * By redefining C, we can make TRACE_FLAGS a list of masks that + * use the bits as defined above. + */ +#undef C +#define C(a, b) TRACE_ITER_##a = (1 << TRACE_ITER_##a##_BIT) + +enum trace_iterator_flags { TRACE_FLAGS }; + +/* * TRACE_ITER_SYM_MASK masks the options in trace_flags that * control the output of kernel symbols. */ @@ -946,7 +1009,7 @@ extern int enable_branch_tracing(struct trace_array *tr); extern void disable_branch_tracing(void); static inline int trace_branch_enable(struct trace_array *tr) { - if (trace_flags & TRACE_ITER_BRANCH) + if (tr->trace_flags & TRACE_ITER_BRANCH) return enable_branch_tracing(tr); return 0; } @@ -1269,6 +1332,7 @@ extern const char *__stop___trace_bprintk_fmt[]; extern const char *__start___tracepoint_str[]; extern const char *__stop___tracepoint_str[]; +void trace_printk_control(bool enabled); void trace_printk_init_buffers(void); void trace_printk_start_comm(void); int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set); diff --git a/kernel/trace/trace_benchmark.c b/kernel/trace/trace_benchmark.c index 40a14cbcf8e0..0f109c4130d3 100644 --- a/kernel/trace/trace_benchmark.c +++ b/kernel/trace/trace_benchmark.c @@ -43,7 +43,7 @@ static void trace_do_benchmark(void) unsigned int std = 0; /* Only run if the tracepoint is actually active */ - if (!trace_benchmark_event_enabled()) + if (!trace_benchmark_event_enabled() || !tracing_is_on()) return; local_irq_disable(); diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c index e2e12ad3186f..3a2a73716a5b 100644 --- a/kernel/trace/trace_branch.c +++ b/kernel/trace/trace_branch.c @@ -125,25 +125,14 @@ void disable_branch_tracing(void) mutex_unlock(&branch_tracing_mutex); } -static void start_branch_trace(struct trace_array *tr) -{ - enable_branch_tracing(tr); -} - -static void stop_branch_trace(struct trace_array *tr) -{ - disable_branch_tracing(); -} - static int branch_trace_init(struct trace_array *tr) { - start_branch_trace(tr); - return 0; + return enable_branch_tracing(tr); } static void branch_trace_reset(struct trace_array *tr) { - stop_branch_trace(tr); + disable_branch_tracing(); } static enum print_line_t trace_branch_print(struct trace_iterator *iter, diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 7ca09cdc20c2..6bbc5f652355 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -15,11 +15,15 @@ #include <linux/kthread.h> #include <linux/tracefs.h> #include <linux/uaccess.h> +#include <linux/bsearch.h> #include <linux/module.h> #include <linux/ctype.h> +#include <linux/sort.h> #include <linux/slab.h> #include <linux/delay.h> +#include <trace/events/sched.h> + #include <asm/setup.h> #include "trace_output.h" @@ -38,21 +42,19 @@ static LIST_HEAD(ftrace_common_fields); static struct kmem_cache *field_cachep; static struct kmem_cache *file_cachep; -#define SYSTEM_FL_FREE_NAME (1 << 31) - static inline int system_refcount(struct event_subsystem *system) { - return system->ref_count & ~SYSTEM_FL_FREE_NAME; + return system->ref_count; } static int system_refcount_inc(struct event_subsystem *system) { - return (system->ref_count++) & ~SYSTEM_FL_FREE_NAME; + return system->ref_count++; } static int system_refcount_dec(struct event_subsystem *system) { - return (--system->ref_count) & ~SYSTEM_FL_FREE_NAME; + return --system->ref_count; } /* Double loops, do not use break, only goto's work */ @@ -212,12 +214,32 @@ int trace_event_raw_init(struct trace_event_call *call) } EXPORT_SYMBOL_GPL(trace_event_raw_init); +bool trace_event_ignore_this_pid(struct trace_event_file *trace_file) +{ + struct trace_array *tr = trace_file->tr; + struct trace_array_cpu *data; + struct trace_pid_list *pid_list; + + pid_list = rcu_dereference_sched(tr->filtered_pids); + if (!pid_list) + return false; + + data = this_cpu_ptr(tr->trace_buffer.data); + + return data->ignore_pid; +} +EXPORT_SYMBOL_GPL(trace_event_ignore_this_pid); + void *trace_event_buffer_reserve(struct trace_event_buffer *fbuffer, struct trace_event_file *trace_file, unsigned long len) { struct trace_event_call *event_call = trace_file->event_call; + if ((trace_file->flags & EVENT_FILE_FL_PID_FILTER) && + trace_event_ignore_this_pid(trace_file)) + return NULL; + local_save_flags(fbuffer->flags); fbuffer->pc = preempt_count(); fbuffer->trace_file = trace_file; @@ -338,6 +360,7 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file, int enable, int soft_disable) { struct trace_event_call *call = file->event_call; + struct trace_array *tr = file->tr; int ret = 0; int disable; @@ -401,7 +424,7 @@ static int __ftrace_event_enable_disable(struct trace_event_file *file, if (soft_disable) set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags); - if (trace_flags & TRACE_ITER_RECORD_CMD) { + if (tr->trace_flags & TRACE_ITER_RECORD_CMD) { tracing_start_cmdline_record(); set_bit(EVENT_FILE_FL_RECORDED_CMD_BIT, &file->flags); } @@ -446,6 +469,142 @@ static void ftrace_clear_events(struct trace_array *tr) mutex_unlock(&event_mutex); } +static int cmp_pid(const void *key, const void *elt) +{ + const pid_t *search_pid = key; + const pid_t *pid = elt; + + if (*search_pid == *pid) + return 0; + if (*search_pid < *pid) + return -1; + return 1; +} + +static bool +check_ignore_pid(struct trace_pid_list *filtered_pids, struct task_struct *task) +{ + pid_t search_pid; + pid_t *pid; + + /* + * Return false, because if filtered_pids does not exist, + * all pids are good to trace. + */ + if (!filtered_pids) + return false; + + search_pid = task->pid; + + pid = bsearch(&search_pid, filtered_pids->pids, + filtered_pids->nr_pids, sizeof(pid_t), + cmp_pid); + if (!pid) + return true; + + return false; +} + +static void +event_filter_pid_sched_switch_probe_pre(void *data, bool preempt, + struct task_struct *prev, struct task_struct *next) +{ + struct trace_array *tr = data; + struct trace_pid_list *pid_list; + + pid_list = rcu_dereference_sched(tr->filtered_pids); + + this_cpu_write(tr->trace_buffer.data->ignore_pid, + check_ignore_pid(pid_list, prev) && + check_ignore_pid(pid_list, next)); +} + +static void +event_filter_pid_sched_switch_probe_post(void *data, bool preempt, + struct task_struct *prev, struct task_struct *next) +{ + struct trace_array *tr = data; + struct trace_pid_list *pid_list; + + pid_list = rcu_dereference_sched(tr->filtered_pids); + + this_cpu_write(tr->trace_buffer.data->ignore_pid, + check_ignore_pid(pid_list, next)); +} + +static void +event_filter_pid_sched_wakeup_probe_pre(void *data, struct task_struct *task) +{ + struct trace_array *tr = data; + struct trace_pid_list *pid_list; + + /* Nothing to do if we are already tracing */ + if (!this_cpu_read(tr->trace_buffer.data->ignore_pid)) + return; + + pid_list = rcu_dereference_sched(tr->filtered_pids); + + this_cpu_write(tr->trace_buffer.data->ignore_pid, + check_ignore_pid(pid_list, task)); +} + +static void +event_filter_pid_sched_wakeup_probe_post(void *data, struct task_struct *task) +{ + struct trace_array *tr = data; + struct trace_pid_list *pid_list; + + /* Nothing to do if we are not tracing */ + if (this_cpu_read(tr->trace_buffer.data->ignore_pid)) + return; + + pid_list = rcu_dereference_sched(tr->filtered_pids); + + /* Set tracing if current is enabled */ + this_cpu_write(tr->trace_buffer.data->ignore_pid, + check_ignore_pid(pid_list, current)); +} + +static void __ftrace_clear_event_pids(struct trace_array *tr) +{ + struct trace_pid_list *pid_list; + struct trace_event_file *file; + int cpu; + + pid_list = rcu_dereference_protected(tr->filtered_pids, + lockdep_is_held(&event_mutex)); + if (!pid_list) + return; + + unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_pre, tr); + unregister_trace_sched_switch(event_filter_pid_sched_switch_probe_post, tr); + + unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre, tr); + unregister_trace_sched_wakeup(event_filter_pid_sched_wakeup_probe_post, tr); + + list_for_each_entry(file, &tr->events, list) { + clear_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags); + } + + for_each_possible_cpu(cpu) + per_cpu_ptr(tr->trace_buffer.data, cpu)->ignore_pid = false; + + rcu_assign_pointer(tr->filtered_pids, NULL); + + /* Wait till all users are no longer using pid filtering */ + synchronize_sched(); + + free_pages((unsigned long)pid_list->pids, pid_list->order); + kfree(pid_list); +} + +static void ftrace_clear_event_pids(struct trace_array *tr) +{ + mutex_lock(&event_mutex); + __ftrace_clear_event_pids(tr); + mutex_unlock(&event_mutex); +} + static void __put_system(struct event_subsystem *system) { struct event_filter *filter = system->filter; @@ -460,8 +619,7 @@ static void __put_system(struct event_subsystem *system) kfree(filter->filter_string); kfree(filter); } - if (system->ref_count & SYSTEM_FL_FREE_NAME) - kfree(system->name); + kfree_const(system->name); kfree(system); } @@ -779,6 +937,58 @@ static void t_stop(struct seq_file *m, void *p) mutex_unlock(&event_mutex); } +static void *p_start(struct seq_file *m, loff_t *pos) + __acquires(RCU) +{ + struct trace_pid_list *pid_list; + struct trace_array *tr = m->private; + + /* + * Grab the mutex, to keep calls to p_next() having the same + * tr->filtered_pids as p_start() has. + * If we just passed the tr->filtered_pids around, then RCU would + * have been enough, but doing that makes things more complex. + */ + mutex_lock(&event_mutex); + rcu_read_lock_sched(); + + pid_list = rcu_dereference_sched(tr->filtered_pids); + + if (!pid_list || *pos >= pid_list->nr_pids) + return NULL; + + return (void *)&pid_list->pids[*pos]; +} + +static void p_stop(struct seq_file *m, void *p) + __releases(RCU) +{ + rcu_read_unlock_sched(); + mutex_unlock(&event_mutex); +} + +static void * +p_next(struct seq_file *m, void *v, loff_t *pos) +{ + struct trace_array *tr = m->private; + struct trace_pid_list *pid_list = rcu_dereference_sched(tr->filtered_pids); + + (*pos)++; + + if (*pos >= pid_list->nr_pids) + return NULL; + + return (void *)&pid_list->pids[*pos]; +} + +static int p_show(struct seq_file *m, void *v) +{ + pid_t *pid = v; + + seq_printf(m, "%d\n", *pid); + return 0; +} + static ssize_t event_enable_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) @@ -1336,8 +1546,209 @@ show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) return r; } +static int max_pids(struct trace_pid_list *pid_list) +{ + return (PAGE_SIZE << pid_list->order) / sizeof(pid_t); +} + +static void ignore_task_cpu(void *data) +{ + struct trace_array *tr = data; + struct trace_pid_list *pid_list; + + /* + * This function is called by on_each_cpu() while the + * event_mutex is held. + */ + pid_list = rcu_dereference_protected(tr->filtered_pids, + mutex_is_locked(&event_mutex)); + + this_cpu_write(tr->trace_buffer.data->ignore_pid, + check_ignore_pid(pid_list, current)); +} + +static ssize_t +ftrace_event_pid_write(struct file *filp, const char __user *ubuf, + size_t cnt, loff_t *ppos) +{ + struct seq_file *m = filp->private_data; + struct trace_array *tr = m->private; + struct trace_pid_list *filtered_pids = NULL; + struct trace_pid_list *pid_list = NULL; + struct trace_event_file *file; + struct trace_parser parser; + unsigned long val; + loff_t this_pos; + ssize_t read = 0; + ssize_t ret = 0; + pid_t pid; + int i; + + if (!cnt) + return 0; + + ret = tracing_update_buffers(); + if (ret < 0) + return ret; + + if (trace_parser_get_init(&parser, EVENT_BUF_SIZE + 1)) + return -ENOMEM; + + mutex_lock(&event_mutex); + /* + * Load as many pids into the array before doing a + * swap from the tr->filtered_pids to the new list. + */ + while (cnt > 0) { + + this_pos = 0; + + ret = trace_get_user(&parser, ubuf, cnt, &this_pos); + if (ret < 0 || !trace_parser_loaded(&parser)) + break; + + read += ret; + ubuf += ret; + cnt -= ret; + + parser.buffer[parser.idx] = 0; + + ret = -EINVAL; + if (kstrtoul(parser.buffer, 0, &val)) + break; + if (val > INT_MAX) + break; + + pid = (pid_t)val; + + ret = -ENOMEM; + if (!pid_list) { + pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL); + if (!pid_list) + break; + + filtered_pids = rcu_dereference_protected(tr->filtered_pids, + lockdep_is_held(&event_mutex)); + if (filtered_pids) + pid_list->order = filtered_pids->order; + else + pid_list->order = 0; + + pid_list->pids = (void *)__get_free_pages(GFP_KERNEL, + pid_list->order); + if (!pid_list->pids) + break; + + if (filtered_pids) { + pid_list->nr_pids = filtered_pids->nr_pids; + memcpy(pid_list->pids, filtered_pids->pids, + pid_list->nr_pids * sizeof(pid_t)); + } else + pid_list->nr_pids = 0; + } + + if (pid_list->nr_pids >= max_pids(pid_list)) { + pid_t *pid_page; + + pid_page = (void *)__get_free_pages(GFP_KERNEL, + pid_list->order + 1); + if (!pid_page) + break; + memcpy(pid_page, pid_list->pids, + pid_list->nr_pids * sizeof(pid_t)); + free_pages((unsigned long)pid_list->pids, pid_list->order); + + pid_list->order++; + pid_list->pids = pid_page; + } + + pid_list->pids[pid_list->nr_pids++] = pid; + trace_parser_clear(&parser); + ret = 0; + } + trace_parser_put(&parser); + + if (ret < 0) { + if (pid_list) + free_pages((unsigned long)pid_list->pids, pid_list->order); + kfree(pid_list); + mutex_unlock(&event_mutex); + return ret; + } + + if (!pid_list) { + mutex_unlock(&event_mutex); + return ret; + } + + sort(pid_list->pids, pid_list->nr_pids, sizeof(pid_t), cmp_pid, NULL); + + /* Remove duplicates */ + for (i = 1; i < pid_list->nr_pids; i++) { + int start = i; + + while (i < pid_list->nr_pids && + pid_list->pids[i - 1] == pid_list->pids[i]) + i++; + + if (start != i) { + if (i < pid_list->nr_pids) { + memmove(&pid_list->pids[start], &pid_list->pids[i], + (pid_list->nr_pids - i) * sizeof(pid_t)); + pid_list->nr_pids -= i - start; + i = start; + } else + pid_list->nr_pids = start; + } + } + + rcu_assign_pointer(tr->filtered_pids, pid_list); + + list_for_each_entry(file, &tr->events, list) { + set_bit(EVENT_FILE_FL_PID_FILTER_BIT, &file->flags); + } + + if (filtered_pids) { + synchronize_sched(); + + free_pages((unsigned long)filtered_pids->pids, filtered_pids->order); + kfree(filtered_pids); + } else { + /* + * Register a probe that is called before all other probes + * to set ignore_pid if next or prev do not match. + * Register a probe this is called after all other probes + * to only keep ignore_pid set if next pid matches. + */ + register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_pre, + tr, INT_MAX); + register_trace_prio_sched_switch(event_filter_pid_sched_switch_probe_post, + tr, 0); + + register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_pre, + tr, INT_MAX); + register_trace_prio_sched_wakeup(event_filter_pid_sched_wakeup_probe_post, + tr, 0); + } + + /* + * Ignoring of pids is done at task switch. But we have to + * check for those tasks that are currently running. + * Always do this in case a pid was appended or removed. + */ + on_each_cpu(ignore_task_cpu, tr, 1); + + mutex_unlock(&event_mutex); + + ret = read; + *ppos += read; + + return ret; +} + static int ftrace_event_avail_open(struct inode *inode, struct file *file); static int ftrace_event_set_open(struct inode *inode, struct file *file); +static int ftrace_event_set_pid_open(struct inode *inode, struct file *file); static int ftrace_event_release(struct inode *inode, struct file *file); static const struct seq_operations show_event_seq_ops = { @@ -1354,6 +1765,13 @@ static const struct seq_operations show_set_event_seq_ops = { .stop = t_stop, }; +static const struct seq_operations show_set_pid_seq_ops = { + .start = p_start, + .next = p_next, + .show = p_show, + .stop = p_stop, +}; + static const struct file_operations ftrace_avail_fops = { .open = ftrace_event_avail_open, .read = seq_read, @@ -1369,6 +1787,14 @@ static const struct file_operations ftrace_set_event_fops = { .release = ftrace_event_release, }; +static const struct file_operations ftrace_set_event_pid_fops = { + .open = ftrace_event_set_pid_open, + .read = seq_read, + .write = ftrace_event_pid_write, + .llseek = seq_lseek, + .release = ftrace_event_release, +}; + static const struct file_operations ftrace_enable_fops = { .open = tracing_open_generic, .read = event_enable_read, @@ -1479,6 +1905,26 @@ ftrace_event_set_open(struct inode *inode, struct file *file) return ret; } +static int +ftrace_event_set_pid_open(struct inode *inode, struct file *file) +{ + const struct seq_operations *seq_ops = &show_set_pid_seq_ops; + struct trace_array *tr = inode->i_private; + int ret; + + if (trace_array_get(tr) < 0) + return -ENODEV; + + if ((file->f_mode & FMODE_WRITE) && + (file->f_flags & O_TRUNC)) + ftrace_clear_event_pids(tr); + + ret = ftrace_event_open(inode, file, seq_ops); + if (ret < 0) + trace_array_put(tr); + return ret; +} + static struct event_subsystem * create_new_subsystem(const char *name) { @@ -1492,13 +1938,9 @@ create_new_subsystem(const char *name) system->ref_count = 1; /* Only allocate if dynamic (kprobes and modules) */ - if (!core_kernel_data((unsigned long)name)) { - system->ref_count |= SYSTEM_FL_FREE_NAME; - system->name = kstrdup(name, GFP_KERNEL); - if (!system->name) - goto out_free; - } else - system->name = name; + system->name = kstrdup_const(name, GFP_KERNEL); + if (!system->name) + goto out_free; system->filter = NULL; @@ -1511,8 +1953,7 @@ create_new_subsystem(const char *name) return system; out_free: - if (system->ref_count & SYSTEM_FL_FREE_NAME) - kfree(system->name); + kfree_const(system->name); kfree(system); return NULL; } @@ -2478,6 +2919,9 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr) return -ENOMEM; } + entry = tracefs_create_file("set_event_pid", 0644, parent, + tr, &ftrace_set_event_pid_fops); + /* ring buffer internal formats */ trace_create_file("header_page", 0444, d_events, ring_buffer_print_page_header, @@ -2558,6 +3002,9 @@ int event_trace_del_tracer(struct trace_array *tr) /* Disable any event triggers and associated soft-disabled events */ clear_event_triggers(tr); + /* Clear the pid list */ + __ftrace_clear_event_pids(tr); + /* Disable any running events */ __ftrace_set_clr_event_nolock(tr, NULL, NULL, NULL, 0); @@ -2595,16 +3042,16 @@ early_enable_events(struct trace_array *tr, bool disable_first) if (!token) break; - if (!*token) - continue; - /* Restarting syscalls requires that we stop them first */ - if (disable_first) - ftrace_set_clr_event(tr, token, 0); + if (*token) { + /* Restarting syscalls requires that we stop them first */ + if (disable_first) + ftrace_set_clr_event(tr, token, 0); - ret = ftrace_set_clr_event(tr, token, 1); - if (ret) - pr_warn("Failed to enable trace event: %s\n", token); + ret = ftrace_set_clr_event(tr, token, 1); + if (ret) + pr_warn("Failed to enable trace event: %s\n", token); + } /* Put back the comma to allow this to be called again */ if (buf) @@ -2891,7 +3338,9 @@ static __init void event_trace_self_tests(void) static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable); -static void +static struct trace_array *event_tr; + +static void __init function_test_events_call(unsigned long ip, unsigned long parent_ip, struct ftrace_ops *op, struct pt_regs *pt_regs) { @@ -2922,7 +3371,7 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip, entry->ip = ip; entry->parent_ip = parent_ip; - trace_buffer_unlock_commit(buffer, event, flags, pc); + trace_buffer_unlock_commit(event_tr, buffer, event, flags, pc); out: atomic_dec(&per_cpu(ftrace_test_event_disable, cpu)); @@ -2938,6 +3387,9 @@ static struct ftrace_ops trace_ops __initdata = static __init void event_trace_self_test_with_function(void) { int ret; + event_tr = top_trace_array(); + if (WARN_ON(!event_tr)) + return; ret = register_ftrace_function(&trace_ops); if (WARN_ON(ret < 0)) { pr_info("Failed to enable function tracer for event tests\n"); diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c index bd1bf184c5c9..f93a219b18da 100644 --- a/kernel/trace/trace_events_filter.c +++ b/kernel/trace/trace_events_filter.c @@ -973,15 +973,15 @@ static bool is_string_field(struct ftrace_event_field *field) field->filter_type == FILTER_PTR_STRING; } -static int is_legal_op(struct ftrace_event_field *field, int op) +static bool is_legal_op(struct ftrace_event_field *field, int op) { if (is_string_field(field) && (op != OP_EQ && op != OP_NE && op != OP_GLOB)) - return 0; + return false; if (!is_string_field(field) && op == OP_GLOB) - return 0; + return false; - return 1; + return true; } static filter_pred_fn_t select_comparison_fn(int op, int field_size, diff --git a/kernel/trace/trace_export.c b/kernel/trace/trace_export.c index adabf7da9113..39aa7aa66468 100644 --- a/kernel/trace/trace_export.c +++ b/kernel/trace/trace_export.c @@ -187,7 +187,7 @@ __attribute__((section("_ftrace_events"))) *__event_##call = &event_##call; FTRACE_ENTRY_REG(call, struct_name, etype, \ PARAMS(tstruct), PARAMS(print), filter, NULL) -int ftrace_event_is_function(struct trace_event_call *call) +bool ftrace_event_is_function(struct trace_event_call *call) { return call == &event_function; } diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index ca98445782ac..92382af7a213 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -83,13 +83,18 @@ static struct tracer_opt trace_opts[] = { { TRACER_OPT(funcgraph-irqs, TRACE_GRAPH_PRINT_IRQS) }, /* Display function name after trailing } */ { TRACER_OPT(funcgraph-tail, TRACE_GRAPH_PRINT_TAIL) }, + /* Include sleep time (scheduled out) between entry and return */ + { TRACER_OPT(sleep-time, TRACE_GRAPH_SLEEP_TIME) }, + /* Include time within nested functions */ + { TRACER_OPT(graph-time, TRACE_GRAPH_GRAPH_TIME) }, { } /* Empty entry */ }; static struct tracer_flags tracer_flags = { /* Don't display overruns, proc, or tail by default */ .val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD | - TRACE_GRAPH_PRINT_DURATION | TRACE_GRAPH_PRINT_IRQS, + TRACE_GRAPH_PRINT_DURATION | TRACE_GRAPH_PRINT_IRQS | + TRACE_GRAPH_SLEEP_TIME | TRACE_GRAPH_GRAPH_TIME, .opts = trace_opts }; @@ -107,8 +112,8 @@ enum { }; static void -print_graph_duration(unsigned long long duration, struct trace_seq *s, - u32 flags); +print_graph_duration(struct trace_array *tr, unsigned long long duration, + struct trace_seq *s, u32 flags); /* Add a function return address to the trace stack on thread info.*/ int @@ -653,6 +658,7 @@ static void print_graph_irq(struct trace_iterator *iter, unsigned long addr, enum trace_type type, int cpu, pid_t pid, u32 flags) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; struct trace_entry *ent = iter->ent; @@ -660,7 +666,7 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr, addr >= (unsigned long)__irqentry_text_end) return; - if (trace_flags & TRACE_ITER_CONTEXT_INFO) { + if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { /* Absolute time */ if (flags & TRACE_GRAPH_PRINT_ABS_TIME) print_graph_abs_time(iter->ts, s); @@ -676,19 +682,19 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr, } /* Latency format */ - if (trace_flags & TRACE_ITER_LATENCY_FMT) + if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) print_graph_lat_fmt(s, ent); } /* No overhead */ - print_graph_duration(0, s, flags | FLAGS_FILL_START); + print_graph_duration(tr, 0, s, flags | FLAGS_FILL_START); if (type == TRACE_GRAPH_ENT) trace_seq_puts(s, "==========>"); else trace_seq_puts(s, "<=========="); - print_graph_duration(0, s, flags | FLAGS_FILL_END); + print_graph_duration(tr, 0, s, flags | FLAGS_FILL_END); trace_seq_putc(s, '\n'); } @@ -726,11 +732,11 @@ trace_print_graph_duration(unsigned long long duration, struct trace_seq *s) } static void -print_graph_duration(unsigned long long duration, struct trace_seq *s, - u32 flags) +print_graph_duration(struct trace_array *tr, unsigned long long duration, + struct trace_seq *s, u32 flags) { if (!(flags & TRACE_GRAPH_PRINT_DURATION) || - !(trace_flags & TRACE_ITER_CONTEXT_INFO)) + !(tr->trace_flags & TRACE_ITER_CONTEXT_INFO)) return; /* No real adata, just filling the column with spaces */ @@ -764,6 +770,7 @@ print_graph_entry_leaf(struct trace_iterator *iter, struct trace_seq *s, u32 flags) { struct fgraph_data *data = iter->private; + struct trace_array *tr = iter->tr; struct ftrace_graph_ret *graph_ret; struct ftrace_graph_ent *call; unsigned long long duration; @@ -792,7 +799,7 @@ print_graph_entry_leaf(struct trace_iterator *iter, } /* Overhead and duration */ - print_graph_duration(duration, s, flags); + print_graph_duration(tr, duration, s, flags); /* Function */ for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) @@ -810,6 +817,7 @@ print_graph_entry_nested(struct trace_iterator *iter, { struct ftrace_graph_ent *call = &entry->graph_ent; struct fgraph_data *data = iter->private; + struct trace_array *tr = iter->tr; int i; if (data) { @@ -825,7 +833,7 @@ print_graph_entry_nested(struct trace_iterator *iter, } /* No time */ - print_graph_duration(0, s, flags | FLAGS_FILL_FULL); + print_graph_duration(tr, 0, s, flags | FLAGS_FILL_FULL); /* Function */ for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) @@ -849,6 +857,7 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s, { struct fgraph_data *data = iter->private; struct trace_entry *ent = iter->ent; + struct trace_array *tr = iter->tr; int cpu = iter->cpu; /* Pid */ @@ -858,7 +867,7 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s, /* Interrupt */ print_graph_irq(iter, addr, type, cpu, ent->pid, flags); - if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) + if (!(tr->trace_flags & TRACE_ITER_CONTEXT_INFO)) return; /* Absolute time */ @@ -876,7 +885,7 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s, } /* Latency format */ - if (trace_flags & TRACE_ITER_LATENCY_FMT) + if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) print_graph_lat_fmt(s, ent); return; @@ -1027,6 +1036,7 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s, { unsigned long long duration = trace->rettime - trace->calltime; struct fgraph_data *data = iter->private; + struct trace_array *tr = iter->tr; pid_t pid = ent->pid; int cpu = iter->cpu; int func_match = 1; @@ -1058,7 +1068,7 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s, print_graph_prologue(iter, s, 0, 0, flags); /* Overhead and duration */ - print_graph_duration(duration, s, flags); + print_graph_duration(tr, duration, s, flags); /* Closing brace */ for (i = 0; i < trace->depth * TRACE_GRAPH_INDENT; i++) @@ -1091,7 +1101,8 @@ static enum print_line_t print_graph_comment(struct trace_seq *s, struct trace_entry *ent, struct trace_iterator *iter, u32 flags) { - unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); + struct trace_array *tr = iter->tr; + unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK); struct fgraph_data *data = iter->private; struct trace_event *event; int depth = 0; @@ -1104,7 +1115,7 @@ print_graph_comment(struct trace_seq *s, struct trace_entry *ent, print_graph_prologue(iter, s, 0, 0, flags); /* No time */ - print_graph_duration(0, s, flags | FLAGS_FILL_FULL); + print_graph_duration(tr, 0, s, flags | FLAGS_FILL_FULL); /* Indentation */ if (depth > 0) @@ -1245,9 +1256,10 @@ static void print_lat_header(struct seq_file *s, u32 flags) seq_printf(s, "#%.*s||| / \n", size, spaces); } -static void __print_graph_headers_flags(struct seq_file *s, u32 flags) +static void __print_graph_headers_flags(struct trace_array *tr, + struct seq_file *s, u32 flags) { - int lat = trace_flags & TRACE_ITER_LATENCY_FMT; + int lat = tr->trace_flags & TRACE_ITER_LATENCY_FMT; if (lat) print_lat_header(s, flags); @@ -1289,11 +1301,12 @@ static void print_graph_headers(struct seq_file *s) void print_graph_headers_flags(struct seq_file *s, u32 flags) { struct trace_iterator *iter = s->private; + struct trace_array *tr = iter->tr; - if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) + if (!(tr->trace_flags & TRACE_ITER_CONTEXT_INFO)) return; - if (trace_flags & TRACE_ITER_LATENCY_FMT) { + if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) { /* print nothing if the buffers are empty */ if (trace_empty(iter)) return; @@ -1301,7 +1314,7 @@ void print_graph_headers_flags(struct seq_file *s, u32 flags) print_trace_header(s, iter); } - __print_graph_headers_flags(s, flags); + __print_graph_headers_flags(tr, s, flags); } void graph_trace_open(struct trace_iterator *iter) @@ -1362,6 +1375,12 @@ func_graph_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) if (bit == TRACE_GRAPH_PRINT_IRQS) ftrace_graph_skip_irqs = !set; + if (bit == TRACE_GRAPH_SLEEP_TIME) + ftrace_graph_sleep_time_control(set); + + if (bit == TRACE_GRAPH_GRAPH_TIME) + ftrace_graph_graph_time_control(set); + return 0; } diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c index 8523ea345f2b..e4e56589ec1d 100644 --- a/kernel/trace/trace_irqsoff.c +++ b/kernel/trace/trace_irqsoff.c @@ -31,7 +31,6 @@ enum { static int trace_type __read_mostly; static int save_flags; -static bool function_enabled; static void stop_irqsoff_tracer(struct trace_array *tr, int graph); static int start_irqsoff_tracer(struct trace_array *tr, int graph); @@ -57,22 +56,16 @@ irq_trace(void) # define irq_trace() (0) #endif -#define TRACE_DISPLAY_GRAPH 1 - -static struct tracer_opt trace_opts[] = { #ifdef CONFIG_FUNCTION_GRAPH_TRACER - /* display latency trace as call graph */ - { TRACER_OPT(display-graph, TRACE_DISPLAY_GRAPH) }, +static int irqsoff_display_graph(struct trace_array *tr, int set); +# define is_graph(tr) ((tr)->trace_flags & TRACE_ITER_DISPLAY_GRAPH) +#else +static inline int irqsoff_display_graph(struct trace_array *tr, int set) +{ + return -EINVAL; +} +# define is_graph(tr) false #endif - { } /* Empty entry */ -}; - -static struct tracer_flags tracer_flags = { - .val = 0, - .opts = trace_opts, -}; - -#define is_graph() (tracer_flags.val & TRACE_DISPLAY_GRAPH) /* * Sequence count - we record it when starting a measurement and @@ -152,15 +145,11 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip, #endif /* CONFIG_FUNCTION_TRACER */ #ifdef CONFIG_FUNCTION_GRAPH_TRACER -static int -irqsoff_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) +static int irqsoff_display_graph(struct trace_array *tr, int set) { int cpu; - if (!(bit & TRACE_DISPLAY_GRAPH)) - return -EINVAL; - - if (!(is_graph() ^ set)) + if (!(is_graph(tr) ^ set)) return 0; stop_irqsoff_tracer(irqsoff_trace, !set); @@ -209,7 +198,7 @@ static void irqsoff_graph_return(struct ftrace_graph_ret *trace) static void irqsoff_trace_open(struct trace_iterator *iter) { - if (is_graph()) + if (is_graph(iter->tr)) graph_trace_open(iter); } @@ -231,7 +220,7 @@ static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) * In graph mode call the graph tracer output function, * otherwise go with the TRACE_FN event handler */ - if (is_graph()) + if (is_graph(iter->tr)) return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS); return TRACE_TYPE_UNHANDLED; @@ -239,7 +228,9 @@ static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) static void irqsoff_print_header(struct seq_file *s) { - if (is_graph()) + struct trace_array *tr = irqsoff_trace; + + if (is_graph(tr)) print_graph_headers_flags(s, GRAPH_TRACER_FLAGS); else trace_default_header(s); @@ -250,7 +241,7 @@ __trace_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, unsigned long flags, int pc) { - if (is_graph()) + if (is_graph(tr)) trace_graph_function(tr, ip, parent_ip, flags, pc); else trace_function(tr, ip, parent_ip, flags, pc); @@ -259,27 +250,23 @@ __trace_function(struct trace_array *tr, #else #define __trace_function trace_function -static int -irqsoff_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) -{ - return -EINVAL; -} - +#ifdef CONFIG_FUNCTION_TRACER static int irqsoff_graph_entry(struct ftrace_graph_ent *trace) { return -1; } +#endif static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) { return TRACE_TYPE_UNHANDLED; } -static void irqsoff_graph_return(struct ftrace_graph_ret *trace) { } static void irqsoff_trace_open(struct trace_iterator *iter) { } static void irqsoff_trace_close(struct trace_iterator *iter) { } #ifdef CONFIG_FUNCTION_TRACER +static void irqsoff_graph_return(struct ftrace_graph_ret *trace) { } static void irqsoff_print_header(struct seq_file *s) { trace_default_header(s); @@ -295,16 +282,16 @@ static void irqsoff_print_header(struct seq_file *s) /* * Should this new latency be reported/recorded? */ -static int report_latency(struct trace_array *tr, cycle_t delta) +static bool report_latency(struct trace_array *tr, cycle_t delta) { if (tracing_thresh) { if (delta < tracing_thresh) - return 0; + return false; } else { if (delta <= tr->max_latency) - return 0; + return false; } - return 1; + return true; } static void @@ -523,12 +510,15 @@ void trace_preempt_off(unsigned long a0, unsigned long a1) } #endif /* CONFIG_PREEMPT_TRACER */ +#ifdef CONFIG_FUNCTION_TRACER +static bool function_enabled; + static int register_irqsoff_function(struct trace_array *tr, int graph, int set) { int ret; /* 'set' is set if TRACE_ITER_FUNCTION is about to be set */ - if (function_enabled || (!set && !(trace_flags & TRACE_ITER_FUNCTION))) + if (function_enabled || (!set && !(tr->trace_flags & TRACE_ITER_FUNCTION))) return 0; if (graph) @@ -556,20 +546,40 @@ static void unregister_irqsoff_function(struct trace_array *tr, int graph) function_enabled = false; } -static void irqsoff_function_set(struct trace_array *tr, int set) +static int irqsoff_function_set(struct trace_array *tr, u32 mask, int set) { + if (!(mask & TRACE_ITER_FUNCTION)) + return 0; + if (set) - register_irqsoff_function(tr, is_graph(), 1); + register_irqsoff_function(tr, is_graph(tr), 1); else - unregister_irqsoff_function(tr, is_graph()); + unregister_irqsoff_function(tr, is_graph(tr)); + return 1; +} +#else +static int register_irqsoff_function(struct trace_array *tr, int graph, int set) +{ + return 0; +} +static void unregister_irqsoff_function(struct trace_array *tr, int graph) { } +static inline int irqsoff_function_set(struct trace_array *tr, u32 mask, int set) +{ + return 0; } +#endif /* CONFIG_FUNCTION_TRACER */ static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set) { struct tracer *tracer = tr->current_trace; - if (mask & TRACE_ITER_FUNCTION) - irqsoff_function_set(tr, set); + if (irqsoff_function_set(tr, mask, set)) + return 0; + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + if (mask & TRACE_ITER_DISPLAY_GRAPH) + return irqsoff_display_graph(tr, set); +#endif return trace_keep_overwrite(tracer, mask, set); } @@ -602,7 +612,7 @@ static int __irqsoff_tracer_init(struct trace_array *tr) if (irqsoff_busy) return -EBUSY; - save_flags = trace_flags; + save_flags = tr->trace_flags; /* non overwrite screws up the latency tracers */ set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1); @@ -618,7 +628,7 @@ static int __irqsoff_tracer_init(struct trace_array *tr) /* Only toplevel instance supports graph tracing */ if (start_irqsoff_tracer(tr, (tr->flags & TRACE_ARRAY_FL_GLOBAL && - is_graph()))) + is_graph(tr)))) printk(KERN_ERR "failed to start irqsoff tracer\n"); irqsoff_busy = true; @@ -630,7 +640,7 @@ static void irqsoff_tracer_reset(struct trace_array *tr) int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT; int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE; - stop_irqsoff_tracer(tr, is_graph()); + stop_irqsoff_tracer(tr, is_graph(tr)); set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag); set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag); @@ -666,8 +676,6 @@ static struct tracer irqsoff_tracer __read_mostly = .print_max = true, .print_header = irqsoff_print_header, .print_line = irqsoff_print_line, - .flags = &tracer_flags, - .set_flag = irqsoff_set_flag, .flag_changed = irqsoff_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_irqsoff, @@ -700,8 +708,6 @@ static struct tracer preemptoff_tracer __read_mostly = .print_max = true, .print_header = irqsoff_print_header, .print_line = irqsoff_print_line, - .flags = &tracer_flags, - .set_flag = irqsoff_set_flag, .flag_changed = irqsoff_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_preemptoff, @@ -736,8 +742,6 @@ static struct tracer preemptirqsoff_tracer __read_mostly = .print_max = true, .print_header = irqsoff_print_header, .print_line = irqsoff_print_line, - .flags = &tracer_flags, - .set_flag = irqsoff_set_flag, .flag_changed = irqsoff_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_preemptirqsoff, diff --git a/kernel/trace/trace_kdb.c b/kernel/trace/trace_kdb.c index 3ccf5c2c1320..57149bce6aad 100644 --- a/kernel/trace/trace_kdb.c +++ b/kernel/trace/trace_kdb.c @@ -21,20 +21,22 @@ static void ftrace_dump_buf(int skip_lines, long cpu_file) /* use static because iter can be a bit big for the stack */ static struct trace_iterator iter; static struct ring_buffer_iter *buffer_iter[CONFIG_NR_CPUS]; + struct trace_array *tr; unsigned int old_userobj; int cnt = 0, cpu; trace_init_global_iter(&iter); iter.buffer_iter = buffer_iter; + tr = iter.tr; for_each_tracing_cpu(cpu) { atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); } - old_userobj = trace_flags; + old_userobj = tr->trace_flags; /* don't look at user memory in panic mode */ - trace_flags &= ~TRACE_ITER_SYM_USEROBJ; + tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ; kdb_printf("Dumping ftrace buffer:\n"); @@ -82,7 +84,7 @@ static void ftrace_dump_buf(int skip_lines, long cpu_file) kdb_printf("---------------------------------\n"); out: - trace_flags = old_userobj; + tr->trace_flags = old_userobj; for_each_tracing_cpu(cpu) { atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); diff --git a/kernel/trace/trace_mmiotrace.c b/kernel/trace/trace_mmiotrace.c index 638e110c5bfd..2be8c4f2403d 100644 --- a/kernel/trace/trace_mmiotrace.c +++ b/kernel/trace/trace_mmiotrace.c @@ -314,7 +314,7 @@ static void __trace_mmiotrace_rw(struct trace_array *tr, entry->rw = *rw; if (!call_filter_check_discard(call, entry, buffer, event)) - trace_buffer_unlock_commit(buffer, event, 0, pc); + trace_buffer_unlock_commit(tr, buffer, event, 0, pc); } void mmio_trace_rw(struct mmiotrace_rw *rw) @@ -344,7 +344,7 @@ static void __trace_mmiotrace_map(struct trace_array *tr, entry->map = *map; if (!call_filter_check_discard(call, entry, buffer, event)) - trace_buffer_unlock_commit(buffer, event, 0, pc); + trace_buffer_unlock_commit(tr, buffer, event, 0, pc); } void mmio_trace_mapping(struct mmiotrace_map *map) diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 8e481a84aeea..282982195e09 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -322,8 +322,8 @@ seq_print_sym_offset(struct trace_seq *s, const char *fmt, # define IP_FMT "%016lx" #endif -int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, - unsigned long ip, unsigned long sym_flags) +static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, + unsigned long ip, unsigned long sym_flags) { struct file *file = NULL; unsigned long vmstart = 0; @@ -355,50 +355,6 @@ int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, } int -seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s, - unsigned long sym_flags) -{ - struct mm_struct *mm = NULL; - unsigned int i; - - if (trace_flags & TRACE_ITER_SYM_USEROBJ) { - struct task_struct *task; - /* - * we do the lookup on the thread group leader, - * since individual threads might have already quit! - */ - rcu_read_lock(); - task = find_task_by_vpid(entry->tgid); - if (task) - mm = get_task_mm(task); - rcu_read_unlock(); - } - - for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { - unsigned long ip = entry->caller[i]; - - if (ip == ULONG_MAX || trace_seq_has_overflowed(s)) - break; - - trace_seq_puts(s, " => "); - - if (!ip) { - trace_seq_puts(s, "??"); - trace_seq_putc(s, '\n'); - continue; - } - - seq_print_user_ip(s, mm, ip, sym_flags); - trace_seq_putc(s, '\n'); - } - - if (mm) - mmput(mm); - - return !trace_seq_has_overflowed(s); -} - -int seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) { if (!ip) { @@ -520,7 +476,8 @@ char trace_find_mark(unsigned long long d) static int lat_print_timestamp(struct trace_iterator *iter, u64 next_ts) { - unsigned long verbose = trace_flags & TRACE_ITER_VERBOSE; + struct trace_array *tr = iter->tr; + unsigned long verbose = tr->trace_flags & TRACE_ITER_VERBOSE; unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS; unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start; unsigned long long rel_ts = next_ts - iter->ts; @@ -563,6 +520,7 @@ lat_print_timestamp(struct trace_iterator *iter, u64 next_ts) int trace_print_context(struct trace_iterator *iter) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; struct trace_entry *entry = iter->ent; unsigned long long t; @@ -574,7 +532,7 @@ int trace_print_context(struct trace_iterator *iter) trace_seq_printf(s, "%16s-%-5d [%03d] ", comm, entry->pid, iter->cpu); - if (trace_flags & TRACE_ITER_IRQ_INFO) + if (tr->trace_flags & TRACE_ITER_IRQ_INFO) trace_print_lat_fmt(s, entry); if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) { @@ -590,14 +548,15 @@ int trace_print_context(struct trace_iterator *iter) int trace_print_lat_context(struct trace_iterator *iter) { - u64 next_ts; + struct trace_array *tr = iter->tr; /* trace_find_next_entry will reset ent_size */ int ent_size = iter->ent_size; struct trace_seq *s = &iter->seq; + u64 next_ts; struct trace_entry *entry = iter->ent, *next_entry = trace_find_next_entry(iter, NULL, &next_ts); - unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); + unsigned long verbose = (tr->trace_flags & TRACE_ITER_VERBOSE); /* Restore the original ent_size */ iter->ent_size = ent_size; @@ -1079,13 +1038,49 @@ static struct trace_event trace_stack_event = { static enum print_line_t trace_user_stack_print(struct trace_iterator *iter, int flags, struct trace_event *event) { + struct trace_array *tr = iter->tr; struct userstack_entry *field; struct trace_seq *s = &iter->seq; + struct mm_struct *mm = NULL; + unsigned int i; trace_assign_type(field, iter->ent); trace_seq_puts(s, "<user stack trace>\n"); - seq_print_userip_objs(field, s, flags); + + if (tr->trace_flags & TRACE_ITER_SYM_USEROBJ) { + struct task_struct *task; + /* + * we do the lookup on the thread group leader, + * since individual threads might have already quit! + */ + rcu_read_lock(); + task = find_task_by_vpid(field->tgid); + if (task) + mm = get_task_mm(task); + rcu_read_unlock(); + } + + for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { + unsigned long ip = field->caller[i]; + + if (ip == ULONG_MAX || trace_seq_has_overflowed(s)) + break; + + trace_seq_puts(s, " => "); + + if (!ip) { + trace_seq_puts(s, "??"); + trace_seq_putc(s, '\n'); + continue; + } + + seq_print_user_ip(s, mm, ip, flags); + trace_seq_putc(s, '\n'); + } + + if (mm) + mmput(mm); return trace_handle_return(s); } diff --git a/kernel/trace/trace_output.h b/kernel/trace/trace_output.h index 4cbfe85b99c8..fabc49bcd493 100644 --- a/kernel/trace/trace_output.h +++ b/kernel/trace/trace_output.h @@ -14,10 +14,6 @@ trace_print_printk_msg_only(struct trace_iterator *iter); extern int seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags); -extern int seq_print_userip_objs(const struct userstack_entry *entry, - struct trace_seq *s, unsigned long sym_flags); -extern int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, - unsigned long ip, unsigned long sym_flags); extern int trace_print_context(struct trace_iterator *iter); extern int trace_print_lat_context(struct trace_iterator *iter); diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c index 36c1455b7567..1c2b28536feb 100644 --- a/kernel/trace/trace_printk.c +++ b/kernel/trace/trace_printk.c @@ -178,6 +178,12 @@ static inline void format_mod_start(void) { } static inline void format_mod_stop(void) { } #endif /* CONFIG_MODULES */ +static bool __read_mostly trace_printk_enabled = true; + +void trace_printk_control(bool enabled) +{ + trace_printk_enabled = enabled; +} __initdata_or_module static struct notifier_block module_trace_bprintk_format_nb = { @@ -192,7 +198,7 @@ int __trace_bprintk(unsigned long ip, const char *fmt, ...) if (unlikely(!fmt)) return 0; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!trace_printk_enabled) return 0; va_start(ap, fmt); @@ -207,7 +213,7 @@ int __ftrace_vbprintk(unsigned long ip, const char *fmt, va_list ap) if (unlikely(!fmt)) return 0; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!trace_printk_enabled) return 0; return trace_vbprintk(ip, fmt, ap); @@ -219,7 +225,7 @@ int __trace_printk(unsigned long ip, const char *fmt, ...) int ret; va_list ap; - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!trace_printk_enabled) return 0; va_start(ap, fmt); @@ -231,7 +237,7 @@ EXPORT_SYMBOL_GPL(__trace_printk); int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap) { - if (!(trace_flags & TRACE_ITER_PRINTK)) + if (!trace_printk_enabled) return 0; return trace_vprintk(ip, fmt, ap); diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index b98dee914542..f6398db09114 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -302,15 +302,15 @@ static nokprobe_inline void call_fetch(struct fetch_param *fprm, } /* Check the name is good for event/group/fields */ -static inline int is_good_name(const char *name) +static inline bool is_good_name(const char *name) { if (!isalpha(*name) && *name != '_') - return 0; + return false; while (*++name != '\0') { if (!isalpha(*name) && !isdigit(*name) && *name != '_') - return 0; + return false; } - return 1; + return true; } static inline struct event_file_link * diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c index f270088e9929..4c896a0101bd 100644 --- a/kernel/trace/trace_sched_switch.c +++ b/kernel/trace/trace_sched_switch.c @@ -16,7 +16,8 @@ static int sched_ref; static DEFINE_MUTEX(sched_register_mutex); static void -probe_sched_switch(void *ignore, struct task_struct *prev, struct task_struct *next) +probe_sched_switch(void *ignore, bool preempt, + struct task_struct *prev, struct task_struct *next) { if (unlikely(!sched_ref)) return; diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c index 12cbe77b4136..9d4399b553a3 100644 --- a/kernel/trace/trace_sched_wakeup.c +++ b/kernel/trace/trace_sched_wakeup.c @@ -34,31 +34,28 @@ static arch_spinlock_t wakeup_lock = static void wakeup_reset(struct trace_array *tr); static void __wakeup_reset(struct trace_array *tr); -static int wakeup_graph_entry(struct ftrace_graph_ent *trace); -static void wakeup_graph_return(struct ftrace_graph_ret *trace); static int save_flags; -static bool function_enabled; - -#define TRACE_DISPLAY_GRAPH 1 -static struct tracer_opt trace_opts[] = { #ifdef CONFIG_FUNCTION_GRAPH_TRACER - /* display latency trace as call graph */ - { TRACER_OPT(display-graph, TRACE_DISPLAY_GRAPH) }, +static int wakeup_display_graph(struct trace_array *tr, int set); +# define is_graph(tr) ((tr)->trace_flags & TRACE_ITER_DISPLAY_GRAPH) +#else +static inline int wakeup_display_graph(struct trace_array *tr, int set) +{ + return 0; +} +# define is_graph(tr) false #endif - { } /* Empty entry */ -}; - -static struct tracer_flags tracer_flags = { - .val = 0, - .opts = trace_opts, -}; -#define is_graph() (tracer_flags.val & TRACE_DISPLAY_GRAPH) #ifdef CONFIG_FUNCTION_TRACER +static int wakeup_graph_entry(struct ftrace_graph_ent *trace); +static void wakeup_graph_return(struct ftrace_graph_ret *trace); + +static bool function_enabled; + /* * Prologue for the wakeup function tracers. * @@ -128,14 +125,13 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip, atomic_dec(&data->disabled); preempt_enable_notrace(); } -#endif /* CONFIG_FUNCTION_TRACER */ static int register_wakeup_function(struct trace_array *tr, int graph, int set) { int ret; /* 'set' is set if TRACE_ITER_FUNCTION is about to be set */ - if (function_enabled || (!set && !(trace_flags & TRACE_ITER_FUNCTION))) + if (function_enabled || (!set && !(tr->trace_flags & TRACE_ITER_FUNCTION))) return 0; if (graph) @@ -163,20 +159,40 @@ static void unregister_wakeup_function(struct trace_array *tr, int graph) function_enabled = false; } -static void wakeup_function_set(struct trace_array *tr, int set) +static int wakeup_function_set(struct trace_array *tr, u32 mask, int set) { + if (!(mask & TRACE_ITER_FUNCTION)) + return 0; + if (set) - register_wakeup_function(tr, is_graph(), 1); + register_wakeup_function(tr, is_graph(tr), 1); else - unregister_wakeup_function(tr, is_graph()); + unregister_wakeup_function(tr, is_graph(tr)); + return 1; +} +#else +static int register_wakeup_function(struct trace_array *tr, int graph, int set) +{ + return 0; +} +static void unregister_wakeup_function(struct trace_array *tr, int graph) { } +static int wakeup_function_set(struct trace_array *tr, u32 mask, int set) +{ + return 0; } +#endif /* CONFIG_FUNCTION_TRACER */ static int wakeup_flag_changed(struct trace_array *tr, u32 mask, int set) { struct tracer *tracer = tr->current_trace; - if (mask & TRACE_ITER_FUNCTION) - wakeup_function_set(tr, set); + if (wakeup_function_set(tr, mask, set)) + return 0; + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + if (mask & TRACE_ITER_DISPLAY_GRAPH) + return wakeup_display_graph(tr, set); +#endif return trace_keep_overwrite(tracer, mask, set); } @@ -203,14 +219,9 @@ static void stop_func_tracer(struct trace_array *tr, int graph) } #ifdef CONFIG_FUNCTION_GRAPH_TRACER -static int -wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) +static int wakeup_display_graph(struct trace_array *tr, int set) { - - if (!(bit & TRACE_DISPLAY_GRAPH)) - return -EINVAL; - - if (!(is_graph() ^ set)) + if (!(is_graph(tr) ^ set)) return 0; stop_func_tracer(tr, !set); @@ -259,7 +270,7 @@ static void wakeup_graph_return(struct ftrace_graph_ret *trace) static void wakeup_trace_open(struct trace_iterator *iter) { - if (is_graph()) + if (is_graph(iter->tr)) graph_trace_open(iter); } @@ -279,7 +290,7 @@ static enum print_line_t wakeup_print_line(struct trace_iterator *iter) * In graph mode call the graph tracer output function, * otherwise go with the TRACE_FN event handler */ - if (is_graph()) + if (is_graph(iter->tr)) return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS); return TRACE_TYPE_UNHANDLED; @@ -287,7 +298,7 @@ static enum print_line_t wakeup_print_line(struct trace_iterator *iter) static void wakeup_print_header(struct seq_file *s) { - if (is_graph()) + if (is_graph(wakeup_trace)) print_graph_headers_flags(s, GRAPH_TRACER_FLAGS); else trace_default_header(s); @@ -298,7 +309,7 @@ __trace_function(struct trace_array *tr, unsigned long ip, unsigned long parent_ip, unsigned long flags, int pc) { - if (is_graph()) + if (is_graph(tr)) trace_graph_function(tr, ip, parent_ip, flags, pc); else trace_function(tr, ip, parent_ip, flags, pc); @@ -306,27 +317,20 @@ __trace_function(struct trace_array *tr, #else #define __trace_function trace_function -static int -wakeup_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) -{ - return -EINVAL; -} - -static int wakeup_graph_entry(struct ftrace_graph_ent *trace) -{ - return -1; -} - static enum print_line_t wakeup_print_line(struct trace_iterator *iter) { return TRACE_TYPE_UNHANDLED; } -static void wakeup_graph_return(struct ftrace_graph_ret *trace) { } static void wakeup_trace_open(struct trace_iterator *iter) { } static void wakeup_trace_close(struct trace_iterator *iter) { } #ifdef CONFIG_FUNCTION_TRACER +static int wakeup_graph_entry(struct ftrace_graph_ent *trace) +{ + return -1; +} +static void wakeup_graph_return(struct ftrace_graph_ret *trace) { } static void wakeup_print_header(struct seq_file *s) { trace_default_header(s); @@ -342,16 +346,16 @@ static void wakeup_print_header(struct seq_file *s) /* * Should this new latency be reported/recorded? */ -static int report_latency(struct trace_array *tr, cycle_t delta) +static bool report_latency(struct trace_array *tr, cycle_t delta) { if (tracing_thresh) { if (delta < tracing_thresh) - return 0; + return false; } else { if (delta <= tr->max_latency) - return 0; + return false; } - return 1; + return true; } static void @@ -388,7 +392,7 @@ tracing_sched_switch_trace(struct trace_array *tr, entry->next_cpu = task_cpu(next); if (!call_filter_check_discard(call, entry, buffer, event)) - trace_buffer_unlock_commit(buffer, event, flags, pc); + trace_buffer_unlock_commit(tr, buffer, event, flags, pc); } static void @@ -416,11 +420,11 @@ tracing_sched_wakeup_trace(struct trace_array *tr, entry->next_cpu = task_cpu(wakee); if (!call_filter_check_discard(call, entry, buffer, event)) - trace_buffer_unlock_commit(buffer, event, flags, pc); + trace_buffer_unlock_commit(tr, buffer, event, flags, pc); } static void notrace -probe_wakeup_sched_switch(void *ignore, +probe_wakeup_sched_switch(void *ignore, bool preempt, struct task_struct *prev, struct task_struct *next) { struct trace_array_cpu *data; @@ -635,7 +639,7 @@ static void start_wakeup_tracer(struct trace_array *tr) */ smp_wmb(); - if (start_func_tracer(tr, is_graph())) + if (start_func_tracer(tr, is_graph(tr))) printk(KERN_ERR "failed to start wakeup tracer\n"); return; @@ -648,7 +652,7 @@ fail_deprobe: static void stop_wakeup_tracer(struct trace_array *tr) { tracer_enabled = 0; - stop_func_tracer(tr, is_graph()); + stop_func_tracer(tr, is_graph(tr)); unregister_trace_sched_switch(probe_wakeup_sched_switch, NULL); unregister_trace_sched_wakeup_new(probe_wakeup, NULL); unregister_trace_sched_wakeup(probe_wakeup, NULL); @@ -659,7 +663,7 @@ static bool wakeup_busy; static int __wakeup_tracer_init(struct trace_array *tr) { - save_flags = trace_flags; + save_flags = tr->trace_flags; /* non overwrite screws up the latency tracers */ set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1); @@ -740,8 +744,6 @@ static struct tracer wakeup_tracer __read_mostly = .print_max = true, .print_header = wakeup_print_header, .print_line = wakeup_print_line, - .flags = &tracer_flags, - .set_flag = wakeup_set_flag, .flag_changed = wakeup_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_wakeup, @@ -762,8 +764,6 @@ static struct tracer wakeup_rt_tracer __read_mostly = .print_max = true, .print_header = wakeup_print_header, .print_line = wakeup_print_line, - .flags = &tracer_flags, - .set_flag = wakeup_set_flag, .flag_changed = wakeup_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_wakeup, @@ -784,8 +784,6 @@ static struct tracer wakeup_dl_tracer __read_mostly = .print_max = true, .print_header = wakeup_print_header, .print_line = wakeup_print_line, - .flags = &tracer_flags, - .set_flag = wakeup_set_flag, .flag_changed = wakeup_flag_changed, #ifdef CONFIG_FTRACE_SELFTEST .selftest = trace_selftest_startup_wakeup, diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c index b746399ab59c..dda9e6742950 100644 --- a/kernel/trace/trace_stack.c +++ b/kernel/trace/trace_stack.c @@ -16,24 +16,22 @@ #include "trace.h" -#define STACK_TRACE_ENTRIES 500 - static unsigned long stack_dump_trace[STACK_TRACE_ENTRIES+1] = { [0 ... (STACK_TRACE_ENTRIES)] = ULONG_MAX }; -static unsigned stack_dump_index[STACK_TRACE_ENTRIES]; +unsigned stack_trace_index[STACK_TRACE_ENTRIES]; /* * Reserve one entry for the passed in ip. This will allow * us to remove most or all of the stack size overhead * added by the stack tracer itself. */ -static struct stack_trace max_stack_trace = { +struct stack_trace stack_trace_max = { .max_entries = STACK_TRACE_ENTRIES - 1, .entries = &stack_dump_trace[0], }; -static unsigned long max_stack_size; -static arch_spinlock_t max_stack_lock = +unsigned long stack_trace_max_size; +arch_spinlock_t stack_trace_max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; static DEFINE_PER_CPU(int, trace_active); @@ -42,30 +40,38 @@ static DEFINE_MUTEX(stack_sysctl_mutex); int stack_tracer_enabled; static int last_stack_tracer_enabled; -static inline void print_max_stack(void) +void stack_trace_print(void) { long i; int size; pr_emerg(" Depth Size Location (%d entries)\n" " ----- ---- --------\n", - max_stack_trace.nr_entries); + stack_trace_max.nr_entries); - for (i = 0; i < max_stack_trace.nr_entries; i++) { + for (i = 0; i < stack_trace_max.nr_entries; i++) { if (stack_dump_trace[i] == ULONG_MAX) break; - if (i+1 == max_stack_trace.nr_entries || + if (i+1 == stack_trace_max.nr_entries || stack_dump_trace[i+1] == ULONG_MAX) - size = stack_dump_index[i]; + size = stack_trace_index[i]; else - size = stack_dump_index[i] - stack_dump_index[i+1]; + size = stack_trace_index[i] - stack_trace_index[i+1]; - pr_emerg("%3ld) %8d %5d %pS\n", i, stack_dump_index[i], + pr_emerg("%3ld) %8d %5d %pS\n", i, stack_trace_index[i], size, (void *)stack_dump_trace[i]); } } -static inline void +/* + * When arch-specific code overides this function, the following + * data should be filled up, assuming stack_trace_max_lock is held to + * prevent concurrent updates. + * stack_trace_index[] + * stack_trace_max + * stack_trace_max_size + */ +void __weak check_stack(unsigned long ip, unsigned long *stack) { unsigned long this_size, flags; unsigned long *p, *top, *start; @@ -78,33 +84,43 @@ check_stack(unsigned long ip, unsigned long *stack) /* Remove the frame of the tracer */ this_size -= frame_size; - if (this_size <= max_stack_size) + if (this_size <= stack_trace_max_size) return; /* we do not handle interrupt stacks yet */ if (!object_is_on_stack(stack)) return; + /* Can't do this from NMI context (can cause deadlocks) */ + if (in_nmi()) + return; + local_irq_save(flags); - arch_spin_lock(&max_stack_lock); + arch_spin_lock(&stack_trace_max_lock); + + /* + * RCU may not be watching, make it see us. + * The stack trace code uses rcu_sched. + */ + rcu_irq_enter(); /* In case another CPU set the tracer_frame on us */ if (unlikely(!frame_size)) this_size -= tracer_frame; /* a race could have already updated it */ - if (this_size <= max_stack_size) + if (this_size <= stack_trace_max_size) goto out; - max_stack_size = this_size; + stack_trace_max_size = this_size; - max_stack_trace.nr_entries = 0; - max_stack_trace.skip = 3; + stack_trace_max.nr_entries = 0; + stack_trace_max.skip = 3; - save_stack_trace(&max_stack_trace); + save_stack_trace(&stack_trace_max); /* Skip over the overhead of the stack tracer itself */ - for (i = 0; i < max_stack_trace.nr_entries; i++) { + for (i = 0; i < stack_trace_max.nr_entries; i++) { if (stack_dump_trace[i] == ip) break; } @@ -124,18 +140,18 @@ check_stack(unsigned long ip, unsigned long *stack) * loop will only happen once. This code only takes place * on a new max, so it is far from a fast path. */ - while (i < max_stack_trace.nr_entries) { + while (i < stack_trace_max.nr_entries) { int found = 0; - stack_dump_index[x] = this_size; + stack_trace_index[x] = this_size; p = start; - for (; p < top && i < max_stack_trace.nr_entries; p++) { + for (; p < top && i < stack_trace_max.nr_entries; p++) { if (stack_dump_trace[i] == ULONG_MAX) break; if (*p == stack_dump_trace[i]) { stack_dump_trace[x] = stack_dump_trace[i++]; - this_size = stack_dump_index[x++] = + this_size = stack_trace_index[x++] = (top - p) * sizeof(unsigned long); found = 1; /* Start the search from here */ @@ -150,7 +166,7 @@ check_stack(unsigned long ip, unsigned long *stack) if (unlikely(!tracer_frame)) { tracer_frame = (p - stack) * sizeof(unsigned long); - max_stack_size -= tracer_frame; + stack_trace_max_size -= tracer_frame; } } } @@ -159,17 +175,18 @@ check_stack(unsigned long ip, unsigned long *stack) i++; } - max_stack_trace.nr_entries = x; + stack_trace_max.nr_entries = x; for (; x < i; x++) stack_dump_trace[x] = ULONG_MAX; if (task_stack_end_corrupted(current)) { - print_max_stack(); + stack_trace_print(); BUG(); } out: - arch_spin_unlock(&max_stack_lock); + rcu_irq_exit(); + arch_spin_unlock(&stack_trace_max_lock); local_irq_restore(flags); } @@ -240,9 +257,9 @@ stack_max_size_write(struct file *filp, const char __user *ubuf, cpu = smp_processor_id(); per_cpu(trace_active, cpu)++; - arch_spin_lock(&max_stack_lock); + arch_spin_lock(&stack_trace_max_lock); *ptr = val; - arch_spin_unlock(&max_stack_lock); + arch_spin_unlock(&stack_trace_max_lock); per_cpu(trace_active, cpu)--; local_irq_restore(flags); @@ -262,7 +279,7 @@ __next(struct seq_file *m, loff_t *pos) { long n = *pos - 1; - if (n > max_stack_trace.nr_entries || stack_dump_trace[n] == ULONG_MAX) + if (n > stack_trace_max.nr_entries || stack_dump_trace[n] == ULONG_MAX) return NULL; m->private = (void *)n; @@ -285,7 +302,7 @@ static void *t_start(struct seq_file *m, loff_t *pos) cpu = smp_processor_id(); per_cpu(trace_active, cpu)++; - arch_spin_lock(&max_stack_lock); + arch_spin_lock(&stack_trace_max_lock); if (*pos == 0) return SEQ_START_TOKEN; @@ -297,7 +314,7 @@ static void t_stop(struct seq_file *m, void *p) { int cpu; - arch_spin_unlock(&max_stack_lock); + arch_spin_unlock(&stack_trace_max_lock); cpu = smp_processor_id(); per_cpu(trace_active, cpu)--; @@ -332,9 +349,9 @@ static int t_show(struct seq_file *m, void *v) seq_printf(m, " Depth Size Location" " (%d entries)\n" " ----- ---- --------\n", - max_stack_trace.nr_entries); + stack_trace_max.nr_entries); - if (!stack_tracer_enabled && !max_stack_size) + if (!stack_tracer_enabled && !stack_trace_max_size) print_disabled(m); return 0; @@ -342,17 +359,17 @@ static int t_show(struct seq_file *m, void *v) i = *(long *)v; - if (i >= max_stack_trace.nr_entries || + if (i >= stack_trace_max.nr_entries || stack_dump_trace[i] == ULONG_MAX) return 0; - if (i+1 == max_stack_trace.nr_entries || + if (i+1 == stack_trace_max.nr_entries || stack_dump_trace[i+1] == ULONG_MAX) - size = stack_dump_index[i]; + size = stack_trace_index[i]; else - size = stack_dump_index[i] - stack_dump_index[i+1]; + size = stack_trace_index[i] - stack_trace_index[i+1]; - seq_printf(m, "%3ld) %8d %5d ", i, stack_dump_index[i], size); + seq_printf(m, "%3ld) %8d %5d ", i, stack_trace_index[i], size); trace_lookup_stack(m, i); @@ -442,7 +459,7 @@ static __init int stack_trace_init(void) return 0; trace_create_file("stack_max_size", 0644, d_tracer, - &max_stack_size, &stack_max_size_fops); + &stack_trace_max_size, &stack_max_size_fops); trace_create_file("stack_trace", 0444, d_tracer, NULL, &stack_trace_fops); diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index 7d567a4b9fa7..0655afbea83f 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -110,6 +110,7 @@ static enum print_line_t print_syscall_enter(struct trace_iterator *iter, int flags, struct trace_event *event) { + struct trace_array *tr = iter->tr; struct trace_seq *s = &iter->seq; struct trace_entry *ent = iter->ent; struct syscall_trace_enter *trace; @@ -136,7 +137,7 @@ print_syscall_enter(struct trace_iterator *iter, int flags, goto end; /* parameter types */ - if (trace_flags & TRACE_ITER_VERBOSE) + if (tr->trace_flags & TRACE_ITER_VERBOSE) trace_seq_printf(s, "%s ", entry->types[i]); /* parameter values */ diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c index 3490407dc7b7..ecd536de603a 100644 --- a/kernel/tracepoint.c +++ b/kernel/tracepoint.c @@ -91,11 +91,13 @@ static void debug_print_probes(struct tracepoint_func *funcs) printk(KERN_DEBUG "Probe %d : %p\n", i, funcs[i].func); } -static struct tracepoint_func *func_add(struct tracepoint_func **funcs, - struct tracepoint_func *tp_func) +static struct tracepoint_func * +func_add(struct tracepoint_func **funcs, struct tracepoint_func *tp_func, + int prio) { - int nr_probes = 0; struct tracepoint_func *old, *new; + int nr_probes = 0; + int pos = -1; if (WARN_ON(!tp_func->func)) return ERR_PTR(-EINVAL); @@ -104,18 +106,33 @@ static struct tracepoint_func *func_add(struct tracepoint_func **funcs, old = *funcs; if (old) { /* (N -> N+1), (N != 0, 1) probes */ - for (nr_probes = 0; old[nr_probes].func; nr_probes++) + for (nr_probes = 0; old[nr_probes].func; nr_probes++) { + /* Insert before probes of lower priority */ + if (pos < 0 && old[nr_probes].prio < prio) + pos = nr_probes; if (old[nr_probes].func == tp_func->func && old[nr_probes].data == tp_func->data) return ERR_PTR(-EEXIST); + } } /* + 2 : one for new probe, one for NULL func */ new = allocate_probes(nr_probes + 2); if (new == NULL) return ERR_PTR(-ENOMEM); - if (old) - memcpy(new, old, nr_probes * sizeof(struct tracepoint_func)); - new[nr_probes] = *tp_func; + if (old) { + if (pos < 0) { + pos = nr_probes; + memcpy(new, old, nr_probes * sizeof(struct tracepoint_func)); + } else { + /* Copy higher priority probes ahead of the new probe */ + memcpy(new, old, pos * sizeof(struct tracepoint_func)); + /* Copy the rest after it. */ + memcpy(new + pos + 1, old + pos, + (nr_probes - pos) * sizeof(struct tracepoint_func)); + } + } else + pos = 0; + new[pos] = *tp_func; new[nr_probes + 1].func = NULL; *funcs = new; debug_print_probes(*funcs); @@ -174,7 +191,7 @@ static void *func_remove(struct tracepoint_func **funcs, * Add the probe function to a tracepoint. */ static int tracepoint_add_func(struct tracepoint *tp, - struct tracepoint_func *func) + struct tracepoint_func *func, int prio) { struct tracepoint_func *old, *tp_funcs; @@ -183,7 +200,7 @@ static int tracepoint_add_func(struct tracepoint *tp, tp_funcs = rcu_dereference_protected(tp->funcs, lockdep_is_held(&tracepoints_mutex)); - old = func_add(&tp_funcs, func); + old = func_add(&tp_funcs, func, prio); if (IS_ERR(old)) { WARN_ON_ONCE(1); return PTR_ERR(old); @@ -240,6 +257,7 @@ static int tracepoint_remove_func(struct tracepoint *tp, * @tp: tracepoint * @probe: probe handler * @data: tracepoint data + * @prio: priority of this function over other registered functions * * Returns 0 if ok, error value on error. * Note: if @tp is within a module, the caller is responsible for @@ -247,7 +265,8 @@ static int tracepoint_remove_func(struct tracepoint *tp, * performed either with a tracepoint module going notifier, or from * within module exit functions. */ -int tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data) +int tracepoint_probe_register_prio(struct tracepoint *tp, void *probe, + void *data, int prio) { struct tracepoint_func tp_func; int ret; @@ -255,10 +274,30 @@ int tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data) mutex_lock(&tracepoints_mutex); tp_func.func = probe; tp_func.data = data; - ret = tracepoint_add_func(tp, &tp_func); + tp_func.prio = prio; + ret = tracepoint_add_func(tp, &tp_func, prio); mutex_unlock(&tracepoints_mutex); return ret; } +EXPORT_SYMBOL_GPL(tracepoint_probe_register_prio); + +/** + * tracepoint_probe_register - Connect a probe to a tracepoint + * @tp: tracepoint + * @probe: probe handler + * @data: tracepoint data + * @prio: priority of this function over other registered functions + * + * Returns 0 if ok, error value on error. + * Note: if @tp is within a module, the caller is responsible for + * unregistering the probe before the module is gone. This can be + * performed either with a tracepoint module going notifier, or from + * within module exit functions. + */ +int tracepoint_probe_register(struct tracepoint *tp, void *probe, void *data) +{ + return tracepoint_probe_register_prio(tp, probe, data, TRACEPOINT_DEFAULT_PRIO); +} EXPORT_SYMBOL_GPL(tracepoint_probe_register); /** diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 64ed1c37bd1f..18f34cf75f74 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -57,8 +57,10 @@ int __read_mostly watchdog_thresh = 10; #ifdef CONFIG_SMP int __read_mostly sysctl_softlockup_all_cpu_backtrace; +int __read_mostly sysctl_hardlockup_all_cpu_backtrace; #else #define sysctl_softlockup_all_cpu_backtrace 0 +#define sysctl_hardlockup_all_cpu_backtrace 0 #endif static struct cpumask watchdog_cpumask __read_mostly; unsigned long *watchdog_cpumask_bits = cpumask_bits(&watchdog_cpumask); @@ -110,8 +112,9 @@ static unsigned long soft_lockup_nmi_warn; * Should we panic when a soft-lockup or hard-lockup occurs: */ #ifdef CONFIG_HARDLOCKUP_DETECTOR -static int hardlockup_panic = +unsigned int __read_mostly hardlockup_panic = CONFIG_BOOTPARAM_HARDLOCKUP_PANIC_VALUE; +static unsigned long hardlockup_allcpu_dumped; /* * We may not want to enable hard lockup detection by default in all cases, * for example when running the kernel as a guest on a hypervisor. In these @@ -173,6 +176,13 @@ static int __init softlockup_all_cpu_backtrace_setup(char *str) return 1; } __setup("softlockup_all_cpu_backtrace=", softlockup_all_cpu_backtrace_setup); +static int __init hardlockup_all_cpu_backtrace_setup(char *str) +{ + sysctl_hardlockup_all_cpu_backtrace = + !!simple_strtol(str, NULL, 0); + return 1; +} +__setup("hardlockup_all_cpu_backtrace=", hardlockup_all_cpu_backtrace_setup); #endif /* @@ -263,15 +273,15 @@ void touch_softlockup_watchdog_sync(void) #ifdef CONFIG_HARDLOCKUP_DETECTOR /* watchdog detector functions */ -static int is_hardlockup(void) +static bool is_hardlockup(void) { unsigned long hrint = __this_cpu_read(hrtimer_interrupts); if (__this_cpu_read(hrtimer_interrupts_saved) == hrint) - return 1; + return true; __this_cpu_write(hrtimer_interrupts_saved, hrint); - return 0; + return false; } #endif @@ -279,7 +289,7 @@ static int is_softlockup(unsigned long touch_ts) { unsigned long now = get_timestamp(); - if (watchdog_enabled & SOFT_WATCHDOG_ENABLED) { + if ((watchdog_enabled & SOFT_WATCHDOG_ENABLED) && watchdog_thresh){ /* Warn about unreasonable delays. */ if (time_after(now, touch_ts + get_softlockup_thresh())) return now - touch_ts; @@ -318,17 +328,30 @@ static void watchdog_overflow_callback(struct perf_event *event, */ if (is_hardlockup()) { int this_cpu = smp_processor_id(); + struct pt_regs *regs = get_irq_regs(); /* only print hardlockups once */ if (__this_cpu_read(hard_watchdog_warn) == true) return; - if (hardlockup_panic) - panic("Watchdog detected hard LOCKUP on cpu %d", - this_cpu); + pr_emerg("Watchdog detected hard LOCKUP on cpu %d", this_cpu); + print_modules(); + print_irqtrace_events(current); + if (regs) + show_regs(regs); else - WARN(1, "Watchdog detected hard LOCKUP on cpu %d", - this_cpu); + dump_stack(); + + /* + * Perform all-CPU dump only once to avoid multiple hardlockups + * generating interleaving traces + */ + if (sysctl_hardlockup_all_cpu_backtrace && + !test_and_set_bit(0, &hardlockup_allcpu_dumped)) + trigger_allbutself_cpu_backtrace(); + + if (hardlockup_panic) + panic("Hard LOCKUP"); __this_cpu_write(hard_watchdog_warn, true); return; @@ -347,6 +370,9 @@ static void watchdog_interrupt_count(void) static int watchdog_nmi_enable(unsigned int cpu); static void watchdog_nmi_disable(unsigned int cpu); +static int watchdog_enable_all_cpus(void); +static void watchdog_disable_all_cpus(void); + /* watchdog kicker functions */ static enum hrtimer_restart watchdog_timer_fn(struct hrtimer *hrtimer) { @@ -651,37 +677,41 @@ static struct smp_hotplug_thread watchdog_threads = { /* * park all watchdog threads that are specified in 'watchdog_cpumask' + * + * This function returns an error if kthread_park() of a watchdog thread + * fails. In this situation, the watchdog threads of some CPUs can already + * be parked and the watchdog threads of other CPUs can still be runnable. + * Callers are expected to handle this special condition as appropriate in + * their context. + * + * This function may only be called in a context that is protected against + * races with CPU hotplug - for example, via get_online_cpus(). */ static int watchdog_park_threads(void) { int cpu, ret = 0; - get_online_cpus(); for_each_watchdog_cpu(cpu) { ret = kthread_park(per_cpu(softlockup_watchdog, cpu)); if (ret) break; } - if (ret) { - for_each_watchdog_cpu(cpu) - kthread_unpark(per_cpu(softlockup_watchdog, cpu)); - } - put_online_cpus(); return ret; } /* * unpark all watchdog threads that are specified in 'watchdog_cpumask' + * + * This function may only be called in a context that is protected against + * races with CPU hotplug - for example, via get_online_cpus(). */ static void watchdog_unpark_threads(void) { int cpu; - get_online_cpus(); for_each_watchdog_cpu(cpu) kthread_unpark(per_cpu(softlockup_watchdog, cpu)); - put_online_cpus(); } /* @@ -691,6 +721,7 @@ int lockup_detector_suspend(void) { int ret = 0; + get_online_cpus(); mutex_lock(&watchdog_proc_mutex); /* * Multiple suspend requests can be active in parallel (counted by @@ -704,6 +735,11 @@ int lockup_detector_suspend(void) if (ret == 0) watchdog_suspended++; + else { + watchdog_disable_all_cpus(); + pr_err("Failed to suspend lockup detectors, disabled\n"); + watchdog_enabled = 0; + } mutex_unlock(&watchdog_proc_mutex); @@ -726,12 +762,20 @@ void lockup_detector_resume(void) watchdog_unpark_threads(); mutex_unlock(&watchdog_proc_mutex); + put_online_cpus(); } -static void update_watchdog_all_cpus(void) +static int update_watchdog_all_cpus(void) { - watchdog_park_threads(); + int ret; + + ret = watchdog_park_threads(); + if (ret) + return ret; + watchdog_unpark_threads(); + + return 0; } static int watchdog_enable_all_cpus(void) @@ -750,15 +794,20 @@ static int watchdog_enable_all_cpus(void) * Enable/disable the lockup detectors or * change the sample period 'on the fly'. */ - update_watchdog_all_cpus(); + err = update_watchdog_all_cpus(); + + if (err) { + watchdog_disable_all_cpus(); + pr_err("Failed to update lockup detectors, disabled\n"); + } } + if (err) + watchdog_enabled = 0; + return err; } -/* prepare/enable/disable routines */ -/* sysctl functions */ -#ifdef CONFIG_SYSCTL static void watchdog_disable_all_cpus(void) { if (watchdog_running) { @@ -767,6 +816,8 @@ static void watchdog_disable_all_cpus(void) } } +#ifdef CONFIG_SYSCTL + /* * Update the run state of the lockup detectors. */ @@ -808,6 +859,7 @@ static int proc_watchdog_common(int which, struct ctl_table *table, int write, int err, old, new; int *watchdog_param = (int *)table->data; + get_online_cpus(); mutex_lock(&watchdog_proc_mutex); if (watchdog_suspended) { @@ -849,15 +901,17 @@ static int proc_watchdog_common(int which, struct ctl_table *table, int write, } while (cmpxchg(&watchdog_enabled, old, new) != old); /* - * Update the run state of the lockup detectors. - * Restore 'watchdog_enabled' on failure. + * Update the run state of the lockup detectors. There is _no_ + * need to check the value returned by proc_watchdog_update() + * and to restore the previous value of 'watchdog_enabled' as + * both lockup detectors are disabled if proc_watchdog_update() + * returns an error. */ err = proc_watchdog_update(); - if (err) - watchdog_enabled = old; } out: mutex_unlock(&watchdog_proc_mutex); + put_online_cpus(); return err; } @@ -899,6 +953,7 @@ int proc_watchdog_thresh(struct ctl_table *table, int write, { int err, old; + get_online_cpus(); mutex_lock(&watchdog_proc_mutex); if (watchdog_suspended) { @@ -914,15 +969,17 @@ int proc_watchdog_thresh(struct ctl_table *table, int write, goto out; /* - * Update the sample period. - * Restore 'watchdog_thresh' on failure. + * Update the sample period. Restore on failure. */ set_sample_period(); err = proc_watchdog_update(); - if (err) + if (err) { watchdog_thresh = old; + set_sample_period(); + } out: mutex_unlock(&watchdog_proc_mutex); + put_online_cpus(); return err; } @@ -937,6 +994,7 @@ int proc_watchdog_cpumask(struct ctl_table *table, int write, { int err; + get_online_cpus(); mutex_lock(&watchdog_proc_mutex); if (watchdog_suspended) { @@ -964,6 +1022,7 @@ int proc_watchdog_cpumask(struct ctl_table *table, int write, } out: mutex_unlock(&watchdog_proc_mutex); + put_online_cpus(); return err; } diff --git a/kernel/workqueue.c b/kernel/workqueue.c index ca71582fcfab..c579dbab2e36 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -1458,13 +1458,13 @@ static void __queue_delayed_work(int cpu, struct workqueue_struct *wq, timer_stats_timer_set_start_info(&dwork->timer); dwork->wq = wq; + /* timer isn't guaranteed to run in this cpu, record earlier */ + if (cpu == WORK_CPU_UNBOUND) + cpu = raw_smp_processor_id(); dwork->cpu = cpu; timer->expires = jiffies + delay; - if (unlikely(cpu != WORK_CPU_UNBOUND)) - add_timer_on(timer, cpu); - else - add_timer(timer); + add_timer_on(timer, cpu); } /** @@ -3199,6 +3199,7 @@ static struct worker_pool *get_unbound_pool(const struct workqueue_attrs *attrs) u32 hash = wqattrs_hash(attrs); struct worker_pool *pool; int node; + int target_node = NUMA_NO_NODE; lockdep_assert_held(&wq_pool_mutex); @@ -3210,13 +3211,25 @@ static struct worker_pool *get_unbound_pool(const struct workqueue_attrs *attrs) } } + /* if cpumask is contained inside a NUMA node, we belong to that node */ + if (wq_numa_enabled) { + for_each_node(node) { + if (cpumask_subset(attrs->cpumask, + wq_numa_possible_cpumask[node])) { + target_node = node; + break; + } + } + } + /* nope, create a new one */ - pool = kzalloc(sizeof(*pool), GFP_KERNEL); + pool = kzalloc_node(sizeof(*pool), GFP_KERNEL, target_node); if (!pool || init_worker_pool(pool) < 0) goto fail; lockdep_set_subclass(&pool->lock, 1); /* see put_pwq() */ copy_workqueue_attrs(pool->attrs, attrs); + pool->node = target_node; /* * no_numa isn't a worker_pool attribute, always clear it. See @@ -3224,17 +3237,6 @@ static struct worker_pool *get_unbound_pool(const struct workqueue_attrs *attrs) */ pool->attrs->no_numa = false; - /* if cpumask is contained inside a NUMA node, we belong to that node */ - if (wq_numa_enabled) { - for_each_node(node) { - if (cpumask_subset(pool->attrs->cpumask, - wq_numa_possible_cpumask[node])) { - pool->node = node; - break; - } - } - } - if (worker_pool_assign_id(pool) < 0) goto fail; |
