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-rw-r--r--kernel/cgroup.c6
-rw-r--r--kernel/cpu.c10
-rw-r--r--kernel/events/core.c99
-rw-r--r--kernel/events/uprobes.c36
-rw-r--r--kernel/futex.c15
-rw-r--r--kernel/hung_task.c2
-rw-r--r--kernel/locking/Makefile1
-rw-r--r--kernel/locking/lglock.c111
-rw-r--r--kernel/locking/percpu-rwsem.c228
-rw-r--r--kernel/locking/qspinlock_paravirt.h26
-rw-r--r--kernel/locking/qspinlock_stat.h4
-rw-r--r--kernel/locking/rwsem-xadd.c92
-rw-r--r--kernel/power/Kconfig4
-rw-r--r--kernel/power/hibernate.c21
-rw-r--r--kernel/power/main.c1
-rw-r--r--kernel/power/power.h2
-rw-r--r--kernel/power/snapshot.c22
-rw-r--r--kernel/power/suspend.c14
-rw-r--r--kernel/rcu/rcuperf.c7
-rw-r--r--kernel/rcu/rcutorture.c62
-rw-r--r--kernel/rcu/sync.c14
-rw-r--r--kernel/rcu/tree.c44
-rw-r--r--kernel/rcu/tree.h1
-rw-r--r--kernel/rcu/tree_exp.h124
-rw-r--r--kernel/rcu/tree_plugin.h1
-rw-r--r--kernel/rcu/tree_trace.c7
-rw-r--r--kernel/rcu/update.c3
-rw-r--r--kernel/sched/core.c7
-rw-r--r--kernel/sched/cpufreq.c2
-rw-r--r--kernel/sched/cpufreq_schedutil.c122
-rw-r--r--kernel/sched/deadline.c5
-rw-r--r--kernel/sched/fair.c23
-rw-r--r--kernel/sched/rt.c5
-rw-r--r--kernel/sched/sched.h40
-rw-r--r--kernel/smp.c52
-rw-r--r--kernel/stop_machine.c42
-rw-r--r--kernel/torture.c27
-rw-r--r--kernel/trace/trace.c24
-rw-r--r--kernel/trace/trace_kprobe.c4
-rw-r--r--kernel/trace/trace_probe.c30
-rw-r--r--kernel/trace/trace_probe.h11
-rw-r--r--kernel/trace/trace_uprobe.c4
-rw-r--r--kernel/up.c18
43 files changed, 790 insertions, 583 deletions
diff --git a/kernel/cgroup.c b/kernel/cgroup.c
index d6b729beba49..9ba28310eab6 100644
--- a/kernel/cgroup.c
+++ b/kernel/cgroup.c
@@ -5627,6 +5627,12 @@ int __init cgroup_init(void)
BUG_ON(cgroup_init_cftypes(NULL, cgroup_dfl_base_files));
BUG_ON(cgroup_init_cftypes(NULL, cgroup_legacy_base_files));
+ /*
+ * The latency of the synchronize_sched() is too high for cgroups,
+ * avoid it at the cost of forcing all readers into the slow path.
+ */
+ rcu_sync_enter_start(&cgroup_threadgroup_rwsem.rss);
+
get_user_ns(init_cgroup_ns.user_ns);
mutex_lock(&cgroup_mutex);
diff --git a/kernel/cpu.c b/kernel/cpu.c
index 341bf80f80bd..92c2451db415 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -889,6 +889,7 @@ void notify_cpu_starting(unsigned int cpu)
struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu);
enum cpuhp_state target = min((int)st->target, CPUHP_AP_ONLINE);
+ rcu_cpu_starting(cpu); /* Enables RCU usage on this CPU. */
while (st->state < target) {
struct cpuhp_step *step;
@@ -1024,12 +1025,13 @@ EXPORT_SYMBOL_GPL(cpu_up);
#ifdef CONFIG_PM_SLEEP_SMP
static cpumask_var_t frozen_cpus;
-int disable_nonboot_cpus(void)
+int freeze_secondary_cpus(int primary)
{
- int cpu, first_cpu, error = 0;
+ int cpu, error = 0;
cpu_maps_update_begin();
- first_cpu = cpumask_first(cpu_online_mask);
+ if (!cpu_online(primary))
+ primary = cpumask_first(cpu_online_mask);
/*
* We take down all of the non-boot CPUs in one shot to avoid races
* with the userspace trying to use the CPU hotplug at the same time
@@ -1038,7 +1040,7 @@ int disable_nonboot_cpus(void)
pr_info("Disabling non-boot CPUs ...\n");
for_each_online_cpu(cpu) {
- if (cpu == first_cpu)
+ if (cpu == primary)
continue;
trace_suspend_resume(TPS("CPU_OFF"), cpu, true);
error = _cpu_down(cpu, 1, CPUHP_OFFLINE);
diff --git a/kernel/events/core.c b/kernel/events/core.c
index fc9bb2225291..7c0d263f6bc5 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1475,8 +1475,7 @@ list_add_event(struct perf_event *event, struct perf_event_context *ctx)
if (event->group_leader == event) {
struct list_head *list;
- if (is_software_event(event))
- event->group_flags |= PERF_GROUP_SOFTWARE;
+ event->group_caps = event->event_caps;
list = ctx_group_list(event, ctx);
list_add_tail(&event->group_entry, list);
@@ -1630,9 +1629,7 @@ static void perf_group_attach(struct perf_event *event)
WARN_ON_ONCE(group_leader->ctx != event->ctx);
- if (group_leader->group_flags & PERF_GROUP_SOFTWARE &&
- !is_software_event(event))
- group_leader->group_flags &= ~PERF_GROUP_SOFTWARE;
+ group_leader->group_caps &= event->event_caps;
list_add_tail(&event->group_entry, &group_leader->sibling_list);
group_leader->nr_siblings++;
@@ -1723,7 +1720,7 @@ static void perf_group_detach(struct perf_event *event)
sibling->group_leader = sibling;
/* Inherit group flags from the previous leader */
- sibling->group_flags = event->group_flags;
+ sibling->group_caps = event->group_caps;
WARN_ON_ONCE(sibling->ctx != event->ctx);
}
@@ -1832,6 +1829,8 @@ group_sched_out(struct perf_event *group_event,
struct perf_event *event;
int state = group_event->state;
+ perf_pmu_disable(ctx->pmu);
+
event_sched_out(group_event, cpuctx, ctx);
/*
@@ -1840,6 +1839,8 @@ group_sched_out(struct perf_event *group_event,
list_for_each_entry(event, &group_event->sibling_list, group_entry)
event_sched_out(event, cpuctx, ctx);
+ perf_pmu_enable(ctx->pmu);
+
if (state == PERF_EVENT_STATE_ACTIVE && group_event->attr.exclusive)
cpuctx->exclusive = 0;
}
@@ -2145,7 +2146,7 @@ static int group_can_go_on(struct perf_event *event,
/*
* Groups consisting entirely of software events can always go on.
*/
- if (event->group_flags & PERF_GROUP_SOFTWARE)
+ if (event->group_caps & PERF_EV_CAP_SOFTWARE)
return 1;
/*
* If an exclusive group is already on, no other hardware
@@ -2491,7 +2492,7 @@ static int __perf_event_stop(void *info)
* while restarting.
*/
if (sd->restart)
- event->pmu->start(event, PERF_EF_START);
+ event->pmu->start(event, 0);
return 0;
}
@@ -2837,19 +2838,36 @@ unlock:
}
}
+static DEFINE_PER_CPU(struct list_head, sched_cb_list);
+
void perf_sched_cb_dec(struct pmu *pmu)
{
+ struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
+
this_cpu_dec(perf_sched_cb_usages);
+
+ if (!--cpuctx->sched_cb_usage)
+ list_del(&cpuctx->sched_cb_entry);
}
+
void perf_sched_cb_inc(struct pmu *pmu)
{
+ struct perf_cpu_context *cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
+
+ if (!cpuctx->sched_cb_usage++)
+ list_add(&cpuctx->sched_cb_entry, this_cpu_ptr(&sched_cb_list));
+
this_cpu_inc(perf_sched_cb_usages);
}
/*
* This function provides the context switch callback to the lower code
* layer. It is invoked ONLY when the context switch callback is enabled.
+ *
+ * This callback is relevant even to per-cpu events; for example multi event
+ * PEBS requires this to provide PID/TID information. This requires we flush
+ * all queued PEBS records before we context switch to a new task.
*/
static void perf_pmu_sched_task(struct task_struct *prev,
struct task_struct *next,
@@ -2857,34 +2875,24 @@ static void perf_pmu_sched_task(struct task_struct *prev,
{
struct perf_cpu_context *cpuctx;
struct pmu *pmu;
- unsigned long flags;
if (prev == next)
return;
- local_irq_save(flags);
-
- rcu_read_lock();
-
- list_for_each_entry_rcu(pmu, &pmus, entry) {
- if (pmu->sched_task) {
- cpuctx = this_cpu_ptr(pmu->pmu_cpu_context);
-
- perf_ctx_lock(cpuctx, cpuctx->task_ctx);
+ list_for_each_entry(cpuctx, this_cpu_ptr(&sched_cb_list), sched_cb_entry) {
+ pmu = cpuctx->unique_pmu; /* software PMUs will not have sched_task */
- perf_pmu_disable(pmu);
+ if (WARN_ON_ONCE(!pmu->sched_task))
+ continue;
- pmu->sched_task(cpuctx->task_ctx, sched_in);
+ perf_ctx_lock(cpuctx, cpuctx->task_ctx);
+ perf_pmu_disable(pmu);
- perf_pmu_enable(pmu);
+ pmu->sched_task(cpuctx->task_ctx, sched_in);
- perf_ctx_unlock(cpuctx, cpuctx->task_ctx);
- }
+ perf_pmu_enable(pmu);
+ perf_ctx_unlock(cpuctx, cpuctx->task_ctx);
}
-
- rcu_read_unlock();
-
- local_irq_restore(flags);
}
static void perf_event_switch(struct task_struct *task,
@@ -3416,6 +3424,22 @@ struct perf_read_data {
int ret;
};
+static int find_cpu_to_read(struct perf_event *event, int local_cpu)
+{
+ int event_cpu = event->oncpu;
+ u16 local_pkg, event_pkg;
+
+ if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) {
+ event_pkg = topology_physical_package_id(event_cpu);
+ local_pkg = topology_physical_package_id(local_cpu);
+
+ if (event_pkg == local_pkg)
+ return local_cpu;
+ }
+
+ return event_cpu;
+}
+
/*
* Cross CPU call to read the hardware event
*/
@@ -3537,7 +3561,7 @@ u64 perf_event_read_local(struct perf_event *event)
static int perf_event_read(struct perf_event *event, bool group)
{
- int ret = 0;
+ int ret = 0, cpu_to_read, local_cpu;
/*
* If event is enabled and currently active on a CPU, update the
@@ -3549,6 +3573,11 @@ static int perf_event_read(struct perf_event *event, bool group)
.group = group,
.ret = 0,
};
+
+ local_cpu = get_cpu();
+ cpu_to_read = find_cpu_to_read(event, local_cpu);
+ put_cpu();
+
/*
* Purposely ignore the smp_call_function_single() return
* value.
@@ -3559,7 +3588,7 @@ static int perf_event_read(struct perf_event *event, bool group)
* Therefore, either way, we'll have an up-to-date event count
* after this.
*/
- (void)smp_call_function_single(event->oncpu, __perf_event_read, &data, 1);
+ (void)smp_call_function_single(cpu_to_read, __perf_event_read, &data, 1);
ret = data.ret;
} else if (event->state == PERF_EVENT_STATE_INACTIVE) {
struct perf_event_context *ctx = event->ctx;
@@ -5350,9 +5379,10 @@ perf_output_sample_regs(struct perf_output_handle *handle,
struct pt_regs *regs, u64 mask)
{
int bit;
+ DECLARE_BITMAP(_mask, 64);
- for_each_set_bit(bit, (const unsigned long *) &mask,
- sizeof(mask) * BITS_PER_BYTE) {
+ bitmap_from_u64(_mask, mask);
+ for_each_set_bit(bit, _mask, sizeof(mask) * BITS_PER_BYTE) {
u64 val;
val = perf_reg_value(regs, bit);
@@ -9505,6 +9535,9 @@ SYSCALL_DEFINE5(perf_event_open,
goto err_alloc;
}
+ if (pmu->task_ctx_nr == perf_sw_context)
+ event->event_caps |= PERF_EV_CAP_SOFTWARE;
+
if (group_leader &&
(is_software_event(event) != is_software_event(group_leader))) {
if (is_software_event(event)) {
@@ -9518,7 +9551,7 @@ SYSCALL_DEFINE5(perf_event_open,
*/
pmu = group_leader->pmu;
} else if (is_software_event(group_leader) &&
- (group_leader->group_flags & PERF_GROUP_SOFTWARE)) {
+ (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) {
/*
* In case the group is a pure software group, and we
* try to add a hardware event, move the whole group to
@@ -10453,6 +10486,8 @@ static void __init perf_event_init_all_cpus(void)
INIT_LIST_HEAD(&per_cpu(pmu_sb_events.list, cpu));
raw_spin_lock_init(&per_cpu(pmu_sb_events.lock, cpu));
+
+ INIT_LIST_HEAD(&per_cpu(sched_cb_list, cpu));
}
}
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index 8c50276b60d1..d4129bb05e5d 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -150,7 +150,7 @@ static loff_t vaddr_to_offset(struct vm_area_struct *vma, unsigned long vaddr)
* Returns 0 on success, -EFAULT on failure.
*/
static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
- struct page *page, struct page *kpage)
+ struct page *old_page, struct page *new_page)
{
struct mm_struct *mm = vma->vm_mm;
spinlock_t *ptl;
@@ -161,49 +161,49 @@ static int __replace_page(struct vm_area_struct *vma, unsigned long addr,
const unsigned long mmun_end = addr + PAGE_SIZE;
struct mem_cgroup *memcg;
- err = mem_cgroup_try_charge(kpage, vma->vm_mm, GFP_KERNEL, &memcg,
+ err = mem_cgroup_try_charge(new_page, vma->vm_mm, GFP_KERNEL, &memcg,
false);
if (err)
return err;
/* For try_to_free_swap() and munlock_vma_page() below */
- lock_page(page);
+ lock_page(old_page);
mmu_notifier_invalidate_range_start(mm, mmun_start, mmun_end);
err = -EAGAIN;
- ptep = page_check_address(page, mm, addr, &ptl, 0);
+ ptep = page_check_address(old_page, mm, addr, &ptl, 0);
if (!ptep) {
- mem_cgroup_cancel_charge(kpage, memcg, false);
+ mem_cgroup_cancel_charge(new_page, memcg, false);
goto unlock;
}
- get_page(kpage);
- page_add_new_anon_rmap(kpage, vma, addr, false);
- mem_cgroup_commit_charge(kpage, memcg, false, false);
- lru_cache_add_active_or_unevictable(kpage, vma);
+ get_page(new_page);
+ page_add_new_anon_rmap(new_page, vma, addr, false);
+ mem_cgroup_commit_charge(new_page, memcg, false, false);
+ lru_cache_add_active_or_unevictable(new_page, vma);
- if (!PageAnon(page)) {
- dec_mm_counter(mm, mm_counter_file(page));
+ if (!PageAnon(old_page)) {
+ dec_mm_counter(mm, mm_counter_file(old_page));
inc_mm_counter(mm, MM_ANONPAGES);
}
flush_cache_page(vma, addr, pte_pfn(*ptep));
ptep_clear_flush_notify(vma, addr, ptep);
- set_pte_at_notify(mm, addr, ptep, mk_pte(kpage, vma->vm_page_prot));
+ set_pte_at_notify(mm, addr, ptep, mk_pte(new_page, vma->vm_page_prot));
- page_remove_rmap(page, false);
- if (!page_mapped(page))
- try_to_free_swap(page);
+ page_remove_rmap(old_page, false);
+ if (!page_mapped(old_page))
+ try_to_free_swap(old_page);
pte_unmap_unlock(ptep, ptl);
if (vma->vm_flags & VM_LOCKED)
- munlock_vma_page(page);
- put_page(page);
+ munlock_vma_page(old_page);
+ put_page(old_page);
err = 0;
unlock:
mmu_notifier_invalidate_range_end(mm, mmun_start, mmun_end);
- unlock_page(page);
+ unlock_page(old_page);
return err;
}
diff --git a/kernel/futex.c b/kernel/futex.c
index 46cb3a301bc1..2c4be467fecd 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -381,8 +381,12 @@ static inline int hb_waiters_pending(struct futex_hash_bucket *hb)
#endif
}
-/*
- * We hash on the keys returned from get_futex_key (see below).
+/**
+ * hash_futex - Return the hash bucket in the global hash
+ * @key: Pointer to the futex key for which the hash is calculated
+ *
+ * We hash on the keys returned from get_futex_key (see below) and return the
+ * corresponding hash bucket in the global hash.
*/
static struct futex_hash_bucket *hash_futex(union futex_key *key)
{
@@ -392,7 +396,12 @@ static struct futex_hash_bucket *hash_futex(union futex_key *key)
return &futex_queues[hash & (futex_hashsize - 1)];
}
-/*
+
+/**
+ * match_futex - Check whether two futex keys are equal
+ * @key1: Pointer to key1
+ * @key2: Pointer to key2
+ *
* Return 1 if two futex_keys are equal, 0 otherwise.
*/
static inline int match_futex(union futex_key *key1, union futex_key *key2)
diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index d234022805dc..432c3d71d195 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -117,7 +117,7 @@ static void check_hung_task(struct task_struct *t, unsigned long timeout)
pr_err("\"echo 0 > /proc/sys/kernel/hung_task_timeout_secs\""
" disables this message.\n");
sched_show_task(t);
- debug_show_held_locks(t);
+ debug_show_all_locks();
touch_nmi_watchdog();
diff --git a/kernel/locking/Makefile b/kernel/locking/Makefile
index 31322a4275cd..6f88e352cd4f 100644
--- a/kernel/locking/Makefile
+++ b/kernel/locking/Makefile
@@ -18,7 +18,6 @@ obj-$(CONFIG_LOCKDEP) += lockdep_proc.o
endif
obj-$(CONFIG_SMP) += spinlock.o
obj-$(CONFIG_LOCK_SPIN_ON_OWNER) += osq_lock.o
-obj-$(CONFIG_SMP) += lglock.o
obj-$(CONFIG_PROVE_LOCKING) += spinlock.o
obj-$(CONFIG_QUEUED_SPINLOCKS) += qspinlock.o
obj-$(CONFIG_RT_MUTEXES) += rtmutex.o
diff --git a/kernel/locking/lglock.c b/kernel/locking/lglock.c
deleted file mode 100644
index 951cfcd10b4a..000000000000
--- a/kernel/locking/lglock.c
+++ /dev/null
@@ -1,111 +0,0 @@
-/* See include/linux/lglock.h for description */
-#include <linux/module.h>
-#include <linux/lglock.h>
-#include <linux/cpu.h>
-#include <linux/string.h>
-
-/*
- * Note there is no uninit, so lglocks cannot be defined in
- * modules (but it's fine to use them from there)
- * Could be added though, just undo lg_lock_init
- */
-
-void lg_lock_init(struct lglock *lg, char *name)
-{
- LOCKDEP_INIT_MAP(&lg->lock_dep_map, name, &lg->lock_key, 0);
-}
-EXPORT_SYMBOL(lg_lock_init);
-
-void lg_local_lock(struct lglock *lg)
-{
- arch_spinlock_t *lock;
-
- preempt_disable();
- lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
- lock = this_cpu_ptr(lg->lock);
- arch_spin_lock(lock);
-}
-EXPORT_SYMBOL(lg_local_lock);
-
-void lg_local_unlock(struct lglock *lg)
-{
- arch_spinlock_t *lock;
-
- lock_release(&lg->lock_dep_map, 1, _RET_IP_);
- lock = this_cpu_ptr(lg->lock);
- arch_spin_unlock(lock);
- preempt_enable();
-}
-EXPORT_SYMBOL(lg_local_unlock);
-
-void lg_local_lock_cpu(struct lglock *lg, int cpu)
-{
- arch_spinlock_t *lock;
-
- preempt_disable();
- lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
- lock = per_cpu_ptr(lg->lock, cpu);
- arch_spin_lock(lock);
-}
-EXPORT_SYMBOL(lg_local_lock_cpu);
-
-void lg_local_unlock_cpu(struct lglock *lg, int cpu)
-{
- arch_spinlock_t *lock;
-
- lock_release(&lg->lock_dep_map, 1, _RET_IP_);
- lock = per_cpu_ptr(lg->lock, cpu);
- arch_spin_unlock(lock);
- preempt_enable();
-}
-EXPORT_SYMBOL(lg_local_unlock_cpu);
-
-void lg_double_lock(struct lglock *lg, int cpu1, int cpu2)
-{
- BUG_ON(cpu1 == cpu2);
-
- /* lock in cpu order, just like lg_global_lock */
- if (cpu2 < cpu1)
- swap(cpu1, cpu2);
-
- preempt_disable();
- lock_acquire_shared(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
- arch_spin_lock(per_cpu_ptr(lg->lock, cpu1));
- arch_spin_lock(per_cpu_ptr(lg->lock, cpu2));
-}
-
-void lg_double_unlock(struct lglock *lg, int cpu1, int cpu2)
-{
- lock_release(&lg->lock_dep_map, 1, _RET_IP_);
- arch_spin_unlock(per_cpu_ptr(lg->lock, cpu1));
- arch_spin_unlock(per_cpu_ptr(lg->lock, cpu2));
- preempt_enable();
-}
-
-void lg_global_lock(struct lglock *lg)
-{
- int i;
-
- preempt_disable();
- lock_acquire_exclusive(&lg->lock_dep_map, 0, 0, NULL, _RET_IP_);
- for_each_possible_cpu(i) {
- arch_spinlock_t *lock;
- lock = per_cpu_ptr(lg->lock, i);
- arch_spin_lock(lock);
- }
-}
-EXPORT_SYMBOL(lg_global_lock);
-
-void lg_global_unlock(struct lglock *lg)
-{
- int i;
-
- lock_release(&lg->lock_dep_map, 1, _RET_IP_);
- for_each_possible_cpu(i) {
- arch_spinlock_t *lock;
- lock = per_cpu_ptr(lg->lock, i);
- arch_spin_unlock(lock);
- }
- preempt_enable();
-}
-EXPORT_SYMBOL(lg_global_unlock);
diff --git a/kernel/locking/percpu-rwsem.c b/kernel/locking/percpu-rwsem.c
index bec0b647f9cc..ce182599cf2e 100644
--- a/kernel/locking/percpu-rwsem.c
+++ b/kernel/locking/percpu-rwsem.c
@@ -8,152 +8,186 @@
#include <linux/sched.h>
#include <linux/errno.h>
-int __percpu_init_rwsem(struct percpu_rw_semaphore *brw,
+int __percpu_init_rwsem(struct percpu_rw_semaphore *sem,
const char *name, struct lock_class_key *rwsem_key)
{
- brw->fast_read_ctr = alloc_percpu(int);
- if (unlikely(!brw->fast_read_ctr))
+ sem->read_count = alloc_percpu(int);
+ if (unlikely(!sem->read_count))
return -ENOMEM;
/* ->rw_sem represents the whole percpu_rw_semaphore for lockdep */
- __init_rwsem(&brw->rw_sem, name, rwsem_key);
- rcu_sync_init(&brw->rss, RCU_SCHED_SYNC);
- atomic_set(&brw->slow_read_ctr, 0);
- init_waitqueue_head(&brw->write_waitq);
+ rcu_sync_init(&sem->rss, RCU_SCHED_SYNC);
+ __init_rwsem(&sem->rw_sem, name, rwsem_key);
+ init_waitqueue_head(&sem->writer);
+ sem->readers_block = 0;
return 0;
}
EXPORT_SYMBOL_GPL(__percpu_init_rwsem);
-void percpu_free_rwsem(struct percpu_rw_semaphore *brw)
+void percpu_free_rwsem(struct percpu_rw_semaphore *sem)
{
/*
* XXX: temporary kludge. The error path in alloc_super()
* assumes that percpu_free_rwsem() is safe after kzalloc().
*/
- if (!brw->fast_read_ctr)
+ if (!sem->read_count)
return;
- rcu_sync_dtor(&brw->rss);
- free_percpu(brw->fast_read_ctr);
- brw->fast_read_ctr = NULL; /* catch use after free bugs */
+ rcu_sync_dtor(&sem->rss);
+ free_percpu(sem->read_count);
+ sem->read_count = NULL; /* catch use after free bugs */
}
EXPORT_SYMBOL_GPL(percpu_free_rwsem);
-/*
- * 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.
- */
-static bool update_fast_ctr(struct percpu_rw_semaphore *brw, unsigned int val)
+int __percpu_down_read(struct percpu_rw_semaphore *sem, int try)
{
- bool success;
+ /*
+ * Due to having preemption disabled the decrement happens on
+ * the same CPU as the increment, avoiding the
+ * increment-on-one-CPU-and-decrement-on-another problem.
+ *
+ * If the reader misses the writer's assignment of readers_block, then
+ * the writer is guaranteed to see the reader's increment.
+ *
+ * Conversely, any readers that increment their sem->read_count after
+ * the writer looks are guaranteed to see the readers_block value,
+ * which in turn means that they are guaranteed to immediately
+ * decrement their sem->read_count, so that it doesn't matter that the
+ * writer missed them.
+ */
- preempt_disable();
- success = rcu_sync_is_idle(&brw->rss);
- if (likely(success))
- __this_cpu_add(*brw->fast_read_ctr, val);
- preempt_enable();
+ smp_mb(); /* A matches D */
- return success;
-}
+ /*
+ * If !readers_block the critical section starts here, matched by the
+ * release in percpu_up_write().
+ */
+ if (likely(!smp_load_acquire(&sem->readers_block)))
+ return 1;
-/*
- * Like the normal down_read() this is not recursive, the writer can
- * come after the first percpu_down_read() and create the deadlock.
- *
- * Note: returns with lock_is_held(brw->rw_sem) == T for lockdep,
- * percpu_up_read() does rwsem_release(). This pairs with the usage
- * of ->rw_sem in percpu_down/up_write().
- */
-void percpu_down_read(struct percpu_rw_semaphore *brw)
-{
- might_sleep();
- rwsem_acquire_read(&brw->rw_sem.dep_map, 0, 0, _RET_IP_);
+ /*
+ * Per the above comment; we still have preemption disabled and
+ * will thus decrement on the same CPU as we incremented.
+ */
+ __percpu_up_read(sem);
- if (likely(update_fast_ctr(brw, +1)))
- return;
+ if (try)
+ return 0;
- /* Avoid rwsem_acquire_read() and rwsem_release() */
- __down_read(&brw->rw_sem);
- atomic_inc(&brw->slow_read_ctr);
- __up_read(&brw->rw_sem);
-}
-EXPORT_SYMBOL_GPL(percpu_down_read);
+ /*
+ * We either call schedule() in the wait, or we'll fall through
+ * and reschedule on the preempt_enable() in percpu_down_read().
+ */
+ preempt_enable_no_resched();
-int percpu_down_read_trylock(struct percpu_rw_semaphore *brw)
-{
- if (unlikely(!update_fast_ctr(brw, +1))) {
- if (!__down_read_trylock(&brw->rw_sem))
- return 0;
- atomic_inc(&brw->slow_read_ctr);
- __up_read(&brw->rw_sem);
- }
-
- rwsem_acquire_read(&brw->rw_sem.dep_map, 0, 1, _RET_IP_);
+ /*
+ * Avoid lockdep for the down/up_read() we already have them.
+ */
+ __down_read(&sem->rw_sem);
+ this_cpu_inc(*sem->read_count);
+ __up_read(&sem->rw_sem);
+
+ preempt_disable();
return 1;
}
+EXPORT_SYMBOL_GPL(__percpu_down_read);
-void percpu_up_read(struct percpu_rw_semaphore *brw)
+void __percpu_up_read(struct percpu_rw_semaphore *sem)
{
- rwsem_release(&brw->rw_sem.dep_map, 1, _RET_IP_);
-
- if (likely(update_fast_ctr(brw, -1)))
- return;
+ smp_mb(); /* B matches C */
+ /*
+ * In other words, if they see our decrement (presumably to aggregate
+ * zero, as that is the only time it matters) they will also see our
+ * critical section.
+ */
+ __this_cpu_dec(*sem->read_count);
- /* false-positive is possible but harmless */
- if (atomic_dec_and_test(&brw->slow_read_ctr))
- wake_up_all(&brw->write_waitq);
+ /* Prod writer to recheck readers_active */
+ wake_up(&sem->writer);
}
-EXPORT_SYMBOL_GPL(percpu_up_read);
+EXPORT_SYMBOL_GPL(__percpu_up_read);
+
+#define per_cpu_sum(var) \
+({ \
+ typeof(var) __sum = 0; \
+ int cpu; \
+ compiletime_assert_atomic_type(__sum); \
+ for_each_possible_cpu(cpu) \
+ __sum += per_cpu(var, cpu); \
+ __sum; \
+})
-static int clear_fast_ctr(struct percpu_rw_semaphore *brw)
+/*
+ * Return true if the modular sum of the sem->read_count per-CPU variable is
+ * zero. If this sum is zero, then it is stable due to the fact that if any
+ * newly arriving readers increment a given counter, they will immediately
+ * decrement that same counter.
+ */
+static bool readers_active_check(struct percpu_rw_semaphore *sem)
{
- unsigned int sum = 0;
- int cpu;
+ if (per_cpu_sum(*sem->read_count) != 0)
+ return false;
+
+ /*
+ * If we observed the decrement; ensure we see the entire critical
+ * section.
+ */
- for_each_possible_cpu(cpu) {
- sum += per_cpu(*brw->fast_read_ctr, cpu);
- per_cpu(*brw->fast_read_ctr, cpu) = 0;
- }
+ smp_mb(); /* C matches B */
- return sum;
+ return true;
}
-void percpu_down_write(struct percpu_rw_semaphore *brw)
+void percpu_down_write(struct percpu_rw_semaphore *sem)
{
+ /* Notify readers to take the slow path. */
+ rcu_sync_enter(&sem->rss);
+
+ down_write(&sem->rw_sem);
+
/*
- * 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.
- *
- * 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.
+ * Notify new readers to block; up until now, and thus throughout the
+ * longish rcu_sync_enter() above, new readers could still come in.
*/
- rcu_sync_enter(&brw->rss);
+ WRITE_ONCE(sem->readers_block, 1);
- /* exclude other writers, and block the new readers completely */
- down_write(&brw->rw_sem);
+ smp_mb(); /* D matches A */
- /* nobody can use fast_read_ctr, move its sum into slow_read_ctr */
- atomic_add(clear_fast_ctr(brw), &brw->slow_read_ctr);
+ /*
+ * If they don't see our writer of readers_block, then we are
+ * guaranteed to see their sem->read_count increment, and therefore
+ * will wait for them.
+ */
- /* wait for all readers to complete their percpu_up_read() */
- wait_event(brw->write_waitq, !atomic_read(&brw->slow_read_ctr));
+ /* Wait for all now active readers to complete. */
+ wait_event(sem->writer, readers_active_check(sem));
}
EXPORT_SYMBOL_GPL(percpu_down_write);
-void percpu_up_write(struct percpu_rw_semaphore *brw)
+void percpu_up_write(struct percpu_rw_semaphore *sem)
{
- /* release the lock, but the readers can't use the fast-path */
- up_write(&brw->rw_sem);
/*
- * 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.
+ * Signal the writer is done, no fast path yet.
+ *
+ * One reason that we cannot just immediately flip to readers_fast is
+ * that new readers might fail to see the results of this writer's
+ * critical section.
+ *
+ * Therefore we force it through the slow path which guarantees an
+ * acquire and thereby guarantees the critical section's consistency.
+ */
+ smp_store_release(&sem->readers_block, 0);
+
+ /*
+ * Release the write lock, this will allow readers back in the game.
+ */
+ up_write(&sem->rw_sem);
+
+ /*
+ * Once this completes (at least one RCU-sched grace period hence) the
+ * reader fast path will be available again. Safe to use outside the
+ * exclusive write lock because its counting.
*/
- rcu_sync_exit(&brw->rss);
+ rcu_sync_exit(&sem->rss);
}
EXPORT_SYMBOL_GPL(percpu_up_write);
diff --git a/kernel/locking/qspinlock_paravirt.h b/kernel/locking/qspinlock_paravirt.h
index 8a99abf58080..e3b5520005db 100644
--- a/kernel/locking/qspinlock_paravirt.h
+++ b/kernel/locking/qspinlock_paravirt.h
@@ -70,11 +70,14 @@ struct pv_node {
static inline bool pv_queued_spin_steal_lock(struct qspinlock *lock)
{
struct __qspinlock *l = (void *)lock;
- int ret = !(atomic_read(&lock->val) & _Q_LOCKED_PENDING_MASK) &&
- (cmpxchg(&l->locked, 0, _Q_LOCKED_VAL) == 0);
- qstat_inc(qstat_pv_lock_stealing, ret);
- return ret;
+ if (!(atomic_read(&lock->val) & _Q_LOCKED_PENDING_MASK) &&
+ (cmpxchg(&l->locked, 0, _Q_LOCKED_VAL) == 0)) {
+ qstat_inc(qstat_pv_lock_stealing, true);
+ return true;
+ }
+
+ return false;
}
/*
@@ -257,7 +260,6 @@ static struct pv_node *pv_unhash(struct qspinlock *lock)
static inline bool
pv_wait_early(struct pv_node *prev, int loop)
{
-
if ((loop & PV_PREV_CHECK_MASK) != 0)
return false;
@@ -286,12 +288,10 @@ static void pv_wait_node(struct mcs_spinlock *node, struct mcs_spinlock *prev)
{
struct pv_node *pn = (struct pv_node *)node;
struct pv_node *pp = (struct pv_node *)prev;
- int waitcnt = 0;
int loop;
bool wait_early;
- /* waitcnt processing will be compiled out if !QUEUED_LOCK_STAT */
- for (;; waitcnt++) {
+ for (;;) {
for (wait_early = false, loop = SPIN_THRESHOLD; loop; loop--) {
if (READ_ONCE(node->locked))
return;
@@ -315,7 +315,6 @@ static void pv_wait_node(struct mcs_spinlock *node, struct mcs_spinlock *prev)
if (!READ_ONCE(node->locked)) {
qstat_inc(qstat_pv_wait_node, true);
- qstat_inc(qstat_pv_wait_again, waitcnt);
qstat_inc(qstat_pv_wait_early, wait_early);
pv_wait(&pn->state, vcpu_halted);
}
@@ -456,12 +455,9 @@ pv_wait_head_or_lock(struct qspinlock *lock, struct mcs_spinlock *node)
pv_wait(&l->locked, _Q_SLOW_VAL);
/*
- * The unlocker should have freed the lock before kicking the
- * CPU. So if the lock is still not free, it is a spurious
- * wakeup or another vCPU has stolen the lock. The current
- * vCPU should spin again.
+ * Because of lock stealing, the queue head vCPU may not be
+ * able to acquire the lock before it has to wait again.
*/
- qstat_inc(qstat_pv_spurious_wakeup, READ_ONCE(l->locked));
}
/*
@@ -544,7 +540,7 @@ __visible void __pv_queued_spin_unlock(struct qspinlock *lock)
* unhash. Otherwise it would be possible to have multiple @lock
* entries, which would be BAD.
*/
- locked = cmpxchg(&l->locked, _Q_LOCKED_VAL, 0);
+ locked = cmpxchg_release(&l->locked, _Q_LOCKED_VAL, 0);
if (likely(locked == _Q_LOCKED_VAL))
return;
diff --git a/kernel/locking/qspinlock_stat.h b/kernel/locking/qspinlock_stat.h
index b9d031516254..eb0a599fcf58 100644
--- a/kernel/locking/qspinlock_stat.h
+++ b/kernel/locking/qspinlock_stat.h
@@ -24,8 +24,8 @@
* pv_latency_wake - average latency (ns) from vCPU kick to wakeup
* pv_lock_slowpath - # of locking operations via the slowpath
* pv_lock_stealing - # of lock stealing operations
- * pv_spurious_wakeup - # of spurious wakeups
- * pv_wait_again - # of vCPU wait's that happened after a vCPU kick
+ * pv_spurious_wakeup - # of spurious wakeups in non-head vCPUs
+ * pv_wait_again - # of wait's after a queue head vCPU kick
* pv_wait_early - # of early vCPU wait's
* pv_wait_head - # of vCPU wait's at the queue head
* pv_wait_node - # of vCPU wait's at a non-head queue node
diff --git a/kernel/locking/rwsem-xadd.c b/kernel/locking/rwsem-xadd.c
index 447e08de1fab..2337b4bb2366 100644
--- a/kernel/locking/rwsem-xadd.c
+++ b/kernel/locking/rwsem-xadd.c
@@ -121,16 +121,19 @@ enum rwsem_wake_type {
* - woken process blocks are discarded from the list after having task zeroed
* - writers are only marked woken if downgrading is false
*/
-static struct rw_semaphore *
-__rwsem_mark_wake(struct rw_semaphore *sem,
- enum rwsem_wake_type wake_type, struct wake_q_head *wake_q)
+static void __rwsem_mark_wake(struct rw_semaphore *sem,
+ enum rwsem_wake_type wake_type,
+ struct wake_q_head *wake_q)
{
- struct rwsem_waiter *waiter;
- struct task_struct *tsk;
- struct list_head *next;
- long oldcount, woken, loop, adjustment;
+ struct rwsem_waiter *waiter, *tmp;
+ long oldcount, woken = 0, adjustment = 0;
+
+ /*
+ * Take a peek at the queue head waiter such that we can determine
+ * the wakeup(s) to perform.
+ */
+ waiter = list_first_entry(&sem->wait_list, struct rwsem_waiter, list);
- waiter = list_entry(sem->wait_list.next, struct rwsem_waiter, list);
if (waiter->type == RWSEM_WAITING_FOR_WRITE) {
if (wake_type == RWSEM_WAKE_ANY) {
/*
@@ -142,19 +145,19 @@ __rwsem_mark_wake(struct rw_semaphore *sem,
*/
wake_q_add(wake_q, waiter->task);
}
- goto out;
+
+ return;
}
- /* Writers might steal the lock before we grant it to the next reader.
+ /*
+ * Writers might steal the lock before we grant it to the next reader.
* We prefer to do the first reader grant before counting readers
* so we can bail out early if a writer stole the lock.
*/
- adjustment = 0;
if (wake_type != RWSEM_WAKE_READ_OWNED) {
adjustment = RWSEM_ACTIVE_READ_BIAS;
try_reader_grant:
oldcount = atomic_long_fetch_add(adjustment, &sem->count);
-
if (unlikely(oldcount < RWSEM_WAITING_BIAS)) {
/*
* If the count is still less than RWSEM_WAITING_BIAS
@@ -164,7 +167,8 @@ __rwsem_mark_wake(struct rw_semaphore *sem,
*/
if (atomic_long_add_return(-adjustment, &sem->count) <
RWSEM_WAITING_BIAS)
- goto out;
+ return;
+
/* Last active locker left. Retry waking readers. */
goto try_reader_grant;
}
@@ -176,38 +180,23 @@ __rwsem_mark_wake(struct rw_semaphore *sem,
rwsem_set_reader_owned(sem);
}
- /* Grant an infinite number of read locks to the readers at the front
- * of the queue. Note we increment the 'active part' of the count by
- * the number of readers before waking any processes up.
+ /*
+ * Grant an infinite number of read locks to the readers at the front
+ * of the queue. We know that woken will be at least 1 as we accounted
+ * for above. Note we increment the 'active part' of the count by the
+ * number of readers before waking any processes up.
*/
- woken = 0;
- do {
- woken++;
+ list_for_each_entry_safe(waiter, tmp, &sem->wait_list, list) {
+ struct task_struct *tsk;
- if (waiter->list.next == &sem->wait_list)
+ if (waiter->type == RWSEM_WAITING_FOR_WRITE)
break;
- waiter = list_entry(waiter->list.next,
- struct rwsem_waiter, list);
-
- } while (waiter->type != RWSEM_WAITING_FOR_WRITE);
-
- adjustment = woken * RWSEM_ACTIVE_READ_BIAS - adjustment;
- if (waiter->type != RWSEM_WAITING_FOR_WRITE)
- /* hit end of list above */
- adjustment -= RWSEM_WAITING_BIAS;
-
- if (adjustment)
- atomic_long_add(adjustment, &sem->count);
-
- next = sem->wait_list.next;
- loop = woken;
- do {
- waiter = list_entry(next, struct rwsem_waiter, list);
- next = waiter->list.next;
+ woken++;
tsk = waiter->task;
wake_q_add(wake_q, tsk);
+ list_del(&waiter->list);
/*
* Ensure that the last operation is setting the reader
* waiter to nil such that rwsem_down_read_failed() cannot
@@ -215,13 +204,16 @@ __rwsem_mark_wake(struct rw_semaphore *sem,
* to the task to wakeup.
*/
smp_store_release(&waiter->task, NULL);
- } while (--loop);
+ }
- sem->wait_list.next = next;
- next->prev = &sem->wait_list;
+ adjustment = woken * RWSEM_ACTIVE_READ_BIAS - adjustment;
+ if (list_empty(&sem->wait_list)) {
+ /* hit end of list above */
+ adjustment -= RWSEM_WAITING_BIAS;
+ }
- out:
- return sem;
+ if (adjustment)
+ atomic_long_add(adjustment, &sem->count);
}
/*
@@ -235,7 +227,6 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
struct task_struct *tsk = current;
WAKE_Q(wake_q);
- /* set up my own style of waitqueue */
waiter.task = tsk;
waiter.type = RWSEM_WAITING_FOR_READ;
@@ -247,7 +238,8 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
/* we're now waiting on the lock, but no longer actively locking */
count = atomic_long_add_return(adjustment, &sem->count);
- /* If there are no active locks, wake the front queued process(es).
+ /*
+ * If there are no active locks, wake the front queued process(es).
*
* If there are no writers and we are first in the queue,
* wake our own waiter to join the existing active readers !
@@ -255,7 +247,7 @@ struct rw_semaphore __sched *rwsem_down_read_failed(struct rw_semaphore *sem)
if (count == RWSEM_WAITING_BIAS ||
(count > RWSEM_WAITING_BIAS &&
adjustment != -RWSEM_ACTIVE_READ_BIAS))
- sem = __rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q);
+ __rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q);
raw_spin_unlock_irq(&sem->wait_lock);
wake_up_q(&wake_q);
@@ -505,7 +497,7 @@ __rwsem_down_write_failed_common(struct rw_semaphore *sem, int state)
if (count > RWSEM_WAITING_BIAS) {
WAKE_Q(wake_q);
- sem = __rwsem_mark_wake(sem, RWSEM_WAKE_READERS, &wake_q);
+ __rwsem_mark_wake(sem, RWSEM_WAKE_READERS, &wake_q);
/*
* The wakeup is normally called _after_ the wait_lock
* is released, but given that we are proactively waking
@@ -614,9 +606,8 @@ struct rw_semaphore *rwsem_wake(struct rw_semaphore *sem)
raw_spin_lock_irqsave(&sem->wait_lock, flags);
locked:
- /* do nothing if list empty */
if (!list_empty(&sem->wait_list))
- sem = __rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q);
+ __rwsem_mark_wake(sem, RWSEM_WAKE_ANY, &wake_q);
raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
wake_up_q(&wake_q);
@@ -638,9 +629,8 @@ struct rw_semaphore *rwsem_downgrade_wake(struct rw_semaphore *sem)
raw_spin_lock_irqsave(&sem->wait_lock, flags);
- /* do nothing if list empty */
if (!list_empty(&sem->wait_list))
- sem = __rwsem_mark_wake(sem, RWSEM_WAKE_READ_OWNED, &wake_q);
+ __rwsem_mark_wake(sem, RWSEM_WAKE_READ_OWNED, &wake_q);
raw_spin_unlock_irqrestore(&sem->wait_lock, flags);
wake_up_q(&wake_q);
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 68d3ebc12601..e8517b63eb37 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -186,7 +186,7 @@ config PM_SLEEP_DEBUG
config DPM_WATCHDOG
bool "Device suspend/resume watchdog"
- depends on PM_DEBUG && PSTORE
+ depends on PM_DEBUG && PSTORE && EXPERT
---help---
Sets up a watchdog timer to capture drivers that are
locked up attempting to suspend/resume a device.
@@ -197,7 +197,7 @@ config DPM_WATCHDOG
config DPM_WATCHDOG_TIMEOUT
int "Watchdog timeout in seconds"
range 1 120
- default 60
+ default 120
depends on DPM_WATCHDOG
config PM_TRACE
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 33c79b6105c5..b26dbc48c75b 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -306,8 +306,10 @@ static int create_image(int platform_mode)
if (error)
printk(KERN_ERR "PM: Error %d creating hibernation image\n",
error);
- if (!in_suspend)
+ if (!in_suspend) {
events_check_enabled = false;
+ clear_free_pages();
+ }
platform_leave(platform_mode);
@@ -1189,22 +1191,6 @@ static int __init nohibernate_setup(char *str)
return 1;
}
-static int __init page_poison_nohibernate_setup(char *str)
-{
-#ifdef CONFIG_PAGE_POISONING_ZERO
- /*
- * The zeroing option for page poison skips the checks on alloc.
- * since hibernation doesn't save free pages there's no way to
- * guarantee the pages will still be zeroed.
- */
- if (!strcmp(str, "on")) {
- pr_info("Disabling hibernation due to page poisoning\n");
- return nohibernate_setup(str);
- }
-#endif
- return 1;
-}
-
__setup("noresume", noresume_setup);
__setup("resume_offset=", resume_offset_setup);
__setup("resume=", resume_setup);
@@ -1212,4 +1198,3 @@ __setup("hibernate=", hibernate_setup);
__setup("resumewait", resumewait_setup);
__setup("resumedelay=", resumedelay_setup);
__setup("nohibernate", nohibernate_setup);
-__setup("page_poison=", page_poison_nohibernate_setup);
diff --git a/kernel/power/main.c b/kernel/power/main.c
index 5ea50b1b7595..281a697fd458 100644
--- a/kernel/power/main.c
+++ b/kernel/power/main.c
@@ -644,6 +644,7 @@ static int __init pm_init(void)
return error;
hibernate_image_size_init();
hibernate_reserved_size_init();
+ pm_states_init();
power_kobj = kobject_create_and_add("power", NULL);
if (!power_kobj)
return -ENOMEM;
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 242d8b827dd5..56d1d0dedf76 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -110,6 +110,8 @@ extern int create_basic_memory_bitmaps(void);
extern void free_basic_memory_bitmaps(void);
extern int hibernate_preallocate_memory(void);
+extern void clear_free_pages(void);
+
/**
* Auxiliary structure used for reading the snapshot image data and
* metadata from and writing them to the list of page backup entries
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index b02228411d57..4f0f0604f1c4 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -1132,6 +1132,28 @@ void free_basic_memory_bitmaps(void)
pr_debug("PM: Basic memory bitmaps freed\n");
}
+void clear_free_pages(void)
+{
+#ifdef CONFIG_PAGE_POISONING_ZERO
+ struct memory_bitmap *bm = free_pages_map;
+ unsigned long pfn;
+
+ if (WARN_ON(!(free_pages_map)))
+ return;
+
+ memory_bm_position_reset(bm);
+ pfn = memory_bm_next_pfn(bm);
+ while (pfn != BM_END_OF_MAP) {
+ if (pfn_valid(pfn))
+ clear_highpage(pfn_to_page(pfn));
+
+ pfn = memory_bm_next_pfn(bm);
+ }
+ memory_bm_position_reset(bm);
+ pr_info("PM: free pages cleared after restore\n");
+#endif /* PAGE_POISONING_ZERO */
+}
+
/**
* snapshot_additional_pages - Estimate the number of extra pages needed.
* @zone: Memory zone to carry out the computation for.
diff --git a/kernel/power/suspend.c b/kernel/power/suspend.c
index 0acab9d7f96f..1e7f5da648d9 100644
--- a/kernel/power/suspend.c
+++ b/kernel/power/suspend.c
@@ -118,10 +118,18 @@ static bool valid_state(suspend_state_t state)
*/
static bool relative_states;
+void __init pm_states_init(void)
+{
+ /*
+ * freeze state should be supported even without any suspend_ops,
+ * initialize pm_states accordingly here
+ */
+ pm_states[PM_SUSPEND_FREEZE] = pm_labels[relative_states ? 0 : 2];
+}
+
static int __init sleep_states_setup(char *str)
{
relative_states = !strncmp(str, "1", 1);
- pm_states[PM_SUSPEND_FREEZE] = pm_labels[relative_states ? 0 : 2];
return 1;
}
@@ -211,7 +219,7 @@ static int platform_suspend_begin(suspend_state_t state)
{
if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->begin)
return freeze_ops->begin();
- else if (suspend_ops->begin)
+ else if (suspend_ops && suspend_ops->begin)
return suspend_ops->begin(state);
else
return 0;
@@ -221,7 +229,7 @@ static void platform_resume_end(suspend_state_t state)
{
if (state == PM_SUSPEND_FREEZE && freeze_ops && freeze_ops->end)
freeze_ops->end();
- else if (suspend_ops->end)
+ else if (suspend_ops && suspend_ops->end)
suspend_ops->end();
}
diff --git a/kernel/rcu/rcuperf.c b/kernel/rcu/rcuperf.c
index d38ab08a3fe7..123ccbd22449 100644
--- a/kernel/rcu/rcuperf.c
+++ b/kernel/rcu/rcuperf.c
@@ -52,7 +52,7 @@ MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.vnet.ibm.com>");
#define PERF_FLAG "-perf:"
#define PERFOUT_STRING(s) \
- pr_alert("%s" PERF_FLAG s "\n", perf_type)
+ pr_alert("%s" PERF_FLAG " %s\n", perf_type, s)
#define VERBOSE_PERFOUT_STRING(s) \
do { if (verbose) pr_alert("%s" PERF_FLAG " %s\n", perf_type, s); } while (0)
#define VERBOSE_PERFOUT_ERRSTRING(s) \
@@ -400,9 +400,8 @@ rcu_perf_writer(void *arg)
sp.sched_priority = 0;
sched_setscheduler_nocheck(current,
SCHED_NORMAL, &sp);
- pr_alert("%s" PERF_FLAG
- "rcu_perf_writer %ld has %d measurements\n",
- perf_type, me, MIN_MEAS);
+ pr_alert("%s%s rcu_perf_writer %ld has %d measurements\n",
+ perf_type, PERF_FLAG, me, MIN_MEAS);
if (atomic_inc_return(&n_rcu_perf_writer_finished) >=
nrealwriters) {
schedule_timeout_interruptible(10);
diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 971e2b138063..bf08fee53dc7 100644
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1238,6 +1238,7 @@ rcu_torture_stats_print(void)
long pipesummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 };
long batchsummary[RCU_TORTURE_PIPE_LEN + 1] = { 0 };
static unsigned long rtcv_snap = ULONG_MAX;
+ struct task_struct *wtp;
for_each_possible_cpu(cpu) {
for (i = 0; i < RCU_TORTURE_PIPE_LEN + 1; i++) {
@@ -1258,8 +1259,9 @@ rcu_torture_stats_print(void)
atomic_read(&n_rcu_torture_alloc),
atomic_read(&n_rcu_torture_alloc_fail),
atomic_read(&n_rcu_torture_free));
- pr_cont("rtmbe: %d rtbke: %ld rtbre: %ld ",
+ pr_cont("rtmbe: %d rtbe: %ld rtbke: %ld rtbre: %ld ",
atomic_read(&n_rcu_torture_mberror),
+ n_rcu_torture_barrier_error,
n_rcu_torture_boost_ktrerror,
n_rcu_torture_boost_rterror);
pr_cont("rtbf: %ld rtb: %ld nt: %ld ",
@@ -1312,10 +1314,12 @@ rcu_torture_stats_print(void)
rcutorture_get_gp_data(cur_ops->ttype,
&flags, &gpnum, &completed);
- pr_alert("??? Writer stall state %s(%d) g%lu c%lu f%#x\n",
+ wtp = READ_ONCE(writer_task);
+ pr_alert("??? Writer stall state %s(%d) g%lu c%lu f%#x ->state %#lx\n",
rcu_torture_writer_state_getname(),
rcu_torture_writer_state,
- gpnum, completed, flags);
+ gpnum, completed, flags,
+ wtp == NULL ? ~0UL : wtp->state);
show_rcu_gp_kthreads();
rcu_ftrace_dump(DUMP_ALL);
}
@@ -1362,12 +1366,12 @@ rcu_torture_print_module_parms(struct rcu_torture_ops *cur_ops, const char *tag)
onoff_interval, onoff_holdoff);
}
-static void rcutorture_booster_cleanup(int cpu)
+static int rcutorture_booster_cleanup(unsigned int cpu)
{
struct task_struct *t;
if (boost_tasks[cpu] == NULL)
- return;
+ return 0;
mutex_lock(&boost_mutex);
t = boost_tasks[cpu];
boost_tasks[cpu] = NULL;
@@ -1375,9 +1379,10 @@ static void rcutorture_booster_cleanup(int cpu)
/* This must be outside of the mutex, otherwise deadlock! */
torture_stop_kthread(rcu_torture_boost, t);
+ return 0;
}
-static int rcutorture_booster_init(int cpu)
+static int rcutorture_booster_init(unsigned int cpu)
{
int retval;
@@ -1577,28 +1582,7 @@ static void rcu_torture_barrier_cleanup(void)
}
}
-static int rcutorture_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu)
-{
- long cpu = (long)hcpu;
-
- switch (action & ~CPU_TASKS_FROZEN) {
- case CPU_ONLINE:
- case CPU_DOWN_FAILED:
- (void)rcutorture_booster_init(cpu);
- break;
- case CPU_DOWN_PREPARE:
- rcutorture_booster_cleanup(cpu);
- break;
- default:
- break;
- }
- return NOTIFY_OK;
-}
-
-static struct notifier_block rcutorture_cpu_nb = {
- .notifier_call = rcutorture_cpu_notify,
-};
+static enum cpuhp_state rcutor_hp;
static void
rcu_torture_cleanup(void)
@@ -1638,11 +1622,8 @@ rcu_torture_cleanup(void)
for (i = 0; i < ncbflooders; i++)
torture_stop_kthread(rcu_torture_cbflood, cbflood_task[i]);
if ((test_boost == 1 && cur_ops->can_boost) ||
- test_boost == 2) {
- unregister_cpu_notifier(&rcutorture_cpu_nb);
- for_each_possible_cpu(i)
- rcutorture_booster_cleanup(i);
- }
+ test_boost == 2)
+ cpuhp_remove_state(rcutor_hp);
/*
* Wait for all RCU callbacks to fire, then do flavor-specific
@@ -1869,14 +1850,13 @@ rcu_torture_init(void)
test_boost == 2) {
boost_starttime = jiffies + test_boost_interval * HZ;
- register_cpu_notifier(&rcutorture_cpu_nb);
- for_each_possible_cpu(i) {
- if (cpu_is_offline(i))
- continue; /* Heuristic: CPU can go offline. */
- firsterr = rcutorture_booster_init(i);
- if (firsterr)
- goto unwind;
- }
+
+ firsterr = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "RCU_TORTURE",
+ rcutorture_booster_init,
+ rcutorture_booster_cleanup);
+ if (firsterr < 0)
+ goto unwind;
+ rcutor_hp = firsterr;
}
firsterr = torture_shutdown_init(shutdown_secs, rcu_torture_cleanup);
if (firsterr)
diff --git a/kernel/rcu/sync.c b/kernel/rcu/sync.c
index be922c9f3d37..50d1861f7759 100644
--- a/kernel/rcu/sync.c
+++ b/kernel/rcu/sync.c
@@ -68,6 +68,8 @@ void rcu_sync_lockdep_assert(struct rcu_sync *rsp)
RCU_LOCKDEP_WARN(!gp_ops[rsp->gp_type].held(),
"suspicious rcu_sync_is_idle() usage");
}
+
+EXPORT_SYMBOL_GPL(rcu_sync_lockdep_assert);
#endif
/**
@@ -83,6 +85,18 @@ void rcu_sync_init(struct rcu_sync *rsp, enum rcu_sync_type type)
}
/**
+ * Must be called after rcu_sync_init() and before first use.
+ *
+ * Ensures rcu_sync_is_idle() returns false and rcu_sync_{enter,exit}()
+ * pairs turn into NO-OPs.
+ */
+void rcu_sync_enter_start(struct rcu_sync *rsp)
+{
+ rsp->gp_count++;
+ rsp->gp_state = GP_PASSED;
+}
+
+/**
* rcu_sync_enter() - Force readers onto slowpath
* @rsp: Pointer to rcu_sync structure to use for synchronization
*
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 5d80925e7fc8..7e2e03879c2e 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -41,7 +41,6 @@
#include <linux/export.h>
#include <linux/completion.h>
#include <linux/moduleparam.h>
-#include <linux/module.h>
#include <linux/percpu.h>
#include <linux/notifier.h>
#include <linux/cpu.h>
@@ -60,7 +59,6 @@
#include "tree.h"
#include "rcu.h"
-MODULE_ALIAS("rcutree");
#ifdef MODULE_PARAM_PREFIX
#undef MODULE_PARAM_PREFIX
#endif
@@ -1848,6 +1846,7 @@ static bool __note_gp_changes(struct rcu_state *rsp, struct rcu_node *rnp,
struct rcu_data *rdp)
{
bool ret;
+ bool need_gp;
/* Handle the ends of any preceding grace periods first. */
if (rdp->completed == rnp->completed &&
@@ -1874,9 +1873,10 @@ 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->cpu_no_qs.b.norm = true;
+ need_gp = !!(rnp->qsmask & rdp->grpmask);
+ rdp->cpu_no_qs.b.norm = need_gp;
rdp->rcu_qs_ctr_snap = __this_cpu_read(rcu_qs_ctr);
- rdp->core_needs_qs = !!(rnp->qsmask & rdp->grpmask);
+ rdp->core_needs_qs = need_gp;
zero_cpu_stall_ticks(rdp);
WRITE_ONCE(rdp->gpwrap, false);
}
@@ -2344,7 +2344,7 @@ static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags)
WARN_ON_ONCE(!rcu_gp_in_progress(rsp));
WRITE_ONCE(rsp->gp_flags, READ_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS);
raw_spin_unlock_irqrestore_rcu_node(rcu_get_root(rsp), flags);
- swake_up(&rsp->gp_wq); /* Memory barrier implied by swake_up() path. */
+ rcu_gp_kthread_wake(rsp);
}
/*
@@ -2970,7 +2970,7 @@ static void force_quiescent_state(struct rcu_state *rsp)
}
WRITE_ONCE(rsp->gp_flags, READ_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS);
raw_spin_unlock_irqrestore_rcu_node(rnp_old, flags);
- swake_up(&rsp->gp_wq); /* Memory barrier implied by swake_up() path. */
+ rcu_gp_kthread_wake(rsp);
}
/*
@@ -3792,8 +3792,6 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp)
rnp = rdp->mynode;
mask = rdp->grpmask;
raw_spin_lock_rcu_node(rnp); /* irqs already disabled. */
- 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. */
@@ -3860,6 +3858,32 @@ int rcutree_dead_cpu(unsigned int cpu)
return 0;
}
+/*
+ * Mark the specified CPU as being online so that subsequent grace periods
+ * (both expedited and normal) will wait on it. Note that this means that
+ * incoming CPUs are not allowed to use RCU read-side critical sections
+ * until this function is called. Failing to observe this restriction
+ * will result in lockdep splats.
+ */
+void rcu_cpu_starting(unsigned int cpu)
+{
+ unsigned long flags;
+ unsigned long mask;
+ struct rcu_data *rdp;
+ struct rcu_node *rnp;
+ struct rcu_state *rsp;
+
+ for_each_rcu_flavor(rsp) {
+ rdp = this_cpu_ptr(rsp->rda);
+ rnp = rdp->mynode;
+ mask = rdp->grpmask;
+ raw_spin_lock_irqsave_rcu_node(rnp, flags);
+ rnp->qsmaskinitnext |= mask;
+ rnp->expmaskinitnext |= mask;
+ raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
+ }
+}
+
#ifdef CONFIG_HOTPLUG_CPU
/*
* The CPU is exiting the idle loop into the arch_cpu_idle_dead()
@@ -4209,8 +4233,10 @@ void __init rcu_init(void)
* or the scheduler are operational.
*/
pm_notifier(rcu_pm_notify, 0);
- for_each_online_cpu(cpu)
+ for_each_online_cpu(cpu) {
rcutree_prepare_cpu(cpu);
+ rcu_cpu_starting(cpu);
+ }
}
#include "tree_exp.h"
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index f714f873bf9d..e99a5234d9ed 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -400,6 +400,7 @@ struct rcu_data {
#ifdef CONFIG_RCU_FAST_NO_HZ
struct rcu_head oom_head;
#endif /* #ifdef CONFIG_RCU_FAST_NO_HZ */
+ atomic_long_t exp_workdone0; /* # done by workqueue. */
atomic_long_t exp_workdone1; /* # done by others #1. */
atomic_long_t exp_workdone2; /* # done by others #2. */
atomic_long_t exp_workdone3; /* # done by others #3. */
diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h
index 6d86ab6ec2c9..24343eb87b58 100644
--- a/kernel/rcu/tree_exp.h
+++ b/kernel/rcu/tree_exp.h
@@ -359,7 +359,8 @@ static void sync_rcu_exp_select_cpus(struct rcu_state *rsp,
struct rcu_dynticks *rdtp = &per_cpu(rcu_dynticks, cpu);
if (raw_smp_processor_id() == cpu ||
- !(atomic_add_return(0, &rdtp->dynticks) & 0x1))
+ !(atomic_add_return(0, &rdtp->dynticks) & 0x1) ||
+ !(rnp->qsmaskinitnext & rdp->grpmask))
mask_ofl_test |= rdp->grpmask;
}
mask_ofl_ipi = rnp->expmask & ~mask_ofl_test;
@@ -384,17 +385,16 @@ retry_ipi:
mask_ofl_ipi &= ~mask;
continue;
}
- /* Failed, raced with offline. */
+ /* Failed, raced with CPU hotplug operation. */
raw_spin_lock_irqsave_rcu_node(rnp, flags);
- if (cpu_online(cpu) &&
+ if ((rnp->qsmaskinitnext & mask) &&
(rnp->expmask & mask)) {
+ /* Online, so delay for a bit and try again. */
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
schedule_timeout_uninterruptible(1);
- if (cpu_online(cpu) &&
- (rnp->expmask & mask))
- goto retry_ipi;
- raw_spin_lock_irqsave_rcu_node(rnp, flags);
+ goto retry_ipi;
}
+ /* CPU really is offline, so we can ignore it. */
if (!(rnp->expmask & mask))
mask_ofl_ipi &= ~mask;
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
@@ -427,12 +427,10 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
jiffies_stall);
if (ret > 0 || sync_rcu_preempt_exp_done(rnp_root))
return;
- if (ret < 0) {
- /* Hit a signal, disable CPU stall warnings. */
- swait_event(rsp->expedited_wq,
- sync_rcu_preempt_exp_done(rnp_root));
- return;
- }
+ WARN_ON(ret < 0); /* workqueues should not be signaled. */
+ if (rcu_cpu_stall_suppress)
+ continue;
+ panic_on_rcu_stall();
pr_err("INFO: %s detected expedited stalls on CPUs/tasks: {",
rsp->name);
ndetected = 0;
@@ -500,7 +498,6 @@ static void rcu_exp_wait_wake(struct rcu_state *rsp, unsigned long s)
* next GP, to proceed.
*/
mutex_lock(&rsp->exp_wake_mutex);
- mutex_unlock(&rsp->exp_mutex);
rcu_for_each_node_breadth_first(rsp, rnp) {
if (ULONG_CMP_LT(READ_ONCE(rnp->exp_seq_rq), s)) {
@@ -516,6 +513,70 @@ static void rcu_exp_wait_wake(struct rcu_state *rsp, unsigned long s)
mutex_unlock(&rsp->exp_wake_mutex);
}
+/* Let the workqueue handler know what it is supposed to do. */
+struct rcu_exp_work {
+ smp_call_func_t rew_func;
+ struct rcu_state *rew_rsp;
+ unsigned long rew_s;
+ struct work_struct rew_work;
+};
+
+/*
+ * Work-queue handler to drive an expedited grace period forward.
+ */
+static void wait_rcu_exp_gp(struct work_struct *wp)
+{
+ struct rcu_exp_work *rewp;
+
+ /* Initialize the rcu_node tree in preparation for the wait. */
+ rewp = container_of(wp, struct rcu_exp_work, rew_work);
+ sync_rcu_exp_select_cpus(rewp->rew_rsp, rewp->rew_func);
+
+ /* Wait and clean up, including waking everyone. */
+ rcu_exp_wait_wake(rewp->rew_rsp, rewp->rew_s);
+}
+
+/*
+ * Given an rcu_state pointer and a smp_call_function() handler, kick
+ * off the specified flavor of expedited grace period.
+ */
+static void _synchronize_rcu_expedited(struct rcu_state *rsp,
+ smp_call_func_t func)
+{
+ struct rcu_data *rdp;
+ struct rcu_exp_work rew;
+ struct rcu_node *rnp;
+ unsigned long s;
+
+ /* If expedited grace periods are prohibited, fall back to normal. */
+ if (rcu_gp_is_normal()) {
+ wait_rcu_gp(rsp->call);
+ return;
+ }
+
+ /* Take a snapshot of the sequence number. */
+ s = rcu_exp_gp_seq_snap(rsp);
+ if (exp_funnel_lock(rsp, s))
+ return; /* Someone else did our work for us. */
+
+ /* Marshall arguments and schedule the expedited grace period. */
+ rew.rew_func = func;
+ rew.rew_rsp = rsp;
+ rew.rew_s = s;
+ INIT_WORK_ONSTACK(&rew.rew_work, wait_rcu_exp_gp);
+ schedule_work(&rew.rew_work);
+
+ /* Wait for expedited grace period to complete. */
+ rdp = per_cpu_ptr(rsp->rda, raw_smp_processor_id());
+ rnp = rcu_get_root(rsp);
+ wait_event(rnp->exp_wq[(s >> 1) & 0x3],
+ sync_exp_work_done(rsp,
+ &rdp->exp_workdone0, s));
+
+ /* Let the next expedited grace period start. */
+ mutex_unlock(&rsp->exp_mutex);
+}
+
/**
* synchronize_sched_expedited - Brute-force RCU-sched grace period
*
@@ -534,29 +595,13 @@ static void rcu_exp_wait_wake(struct rcu_state *rsp, unsigned long s)
*/
void synchronize_sched_expedited(void)
{
- unsigned long s;
struct rcu_state *rsp = &rcu_sched_state;
/* If only one CPU, this is automatically a grace period. */
if (rcu_blocking_is_gp())
return;
- /* If expedited grace periods are prohibited, fall back to normal. */
- if (rcu_gp_is_normal()) {
- wait_rcu_gp(call_rcu_sched);
- return;
- }
-
- /* Take a snapshot of the sequence number. */
- s = rcu_exp_gp_seq_snap(rsp);
- if (exp_funnel_lock(rsp, s))
- return; /* Someone else did our work for us. */
-
- /* Initialize the rcu_node tree in preparation for the wait. */
- sync_rcu_exp_select_cpus(rsp, sync_sched_exp_handler);
-
- /* Wait and clean up, including waking everyone. */
- rcu_exp_wait_wake(rsp, s);
+ _synchronize_rcu_expedited(rsp, sync_sched_exp_handler);
}
EXPORT_SYMBOL_GPL(synchronize_sched_expedited);
@@ -620,23 +665,8 @@ static void sync_rcu_exp_handler(void *info)
void synchronize_rcu_expedited(void)
{
struct rcu_state *rsp = rcu_state_p;
- unsigned long s;
-
- /* If expedited grace periods are prohibited, fall back to normal. */
- if (rcu_gp_is_normal()) {
- wait_rcu_gp(call_rcu);
- return;
- }
-
- s = rcu_exp_gp_seq_snap(rsp);
- if (exp_funnel_lock(rsp, s))
- return; /* Someone else did our work for us. */
-
- /* Initialize the rcu_node tree in preparation for the wait. */
- sync_rcu_exp_select_cpus(rsp, sync_rcu_exp_handler);
- /* Wait for ->blkd_tasks lists to drain, then wake everyone up. */
- rcu_exp_wait_wake(rsp, s);
+ _synchronize_rcu_expedited(rsp, sync_rcu_exp_handler);
}
EXPORT_SYMBOL_GPL(synchronize_rcu_expedited);
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 0082fce402a0..85c5a883c6e3 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -2173,6 +2173,7 @@ static int rcu_nocb_kthread(void *arg)
cl++;
c++;
local_bh_enable();
+ cond_resched_rcu_qs();
list = next;
}
trace_rcu_batch_end(rdp->rsp->name, c, !!list, 0, 0, 1);
diff --git a/kernel/rcu/tree_trace.c b/kernel/rcu/tree_trace.c
index 86782f9a4604..b1f28972872c 100644
--- a/kernel/rcu/tree_trace.c
+++ b/kernel/rcu/tree_trace.c
@@ -185,16 +185,17 @@ static int show_rcuexp(struct seq_file *m, void *v)
int cpu;
struct rcu_state *rsp = (struct rcu_state *)m->private;
struct rcu_data *rdp;
- unsigned long s1 = 0, s2 = 0, s3 = 0;
+ unsigned long s0 = 0, s1 = 0, s2 = 0, s3 = 0;
for_each_possible_cpu(cpu) {
rdp = per_cpu_ptr(rsp->rda, cpu);
+ s0 += atomic_long_read(&rdp->exp_workdone0);
s1 += atomic_long_read(&rdp->exp_workdone1);
s2 += atomic_long_read(&rdp->exp_workdone2);
s3 += atomic_long_read(&rdp->exp_workdone3);
}
- seq_printf(m, "s=%lu wd1=%lu wd2=%lu wd3=%lu n=%lu enq=%d sc=%lu\n",
- rsp->expedited_sequence, s1, s2, s3,
+ seq_printf(m, "s=%lu wd0=%lu wd1=%lu wd2=%lu wd3=%lu n=%lu enq=%d sc=%lu\n",
+ rsp->expedited_sequence, s0, s1, s2, s3,
atomic_long_read(&rsp->expedited_normal),
atomic_read(&rsp->expedited_need_qs),
rsp->expedited_sequence / 2);
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index f0d8322bc3ec..f19271dce0a9 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -46,7 +46,7 @@
#include <linux/export.h>
#include <linux/hardirq.h>
#include <linux/delay.h>
-#include <linux/module.h>
+#include <linux/moduleparam.h>
#include <linux/kthread.h>
#include <linux/tick.h>
@@ -54,7 +54,6 @@
#include "rcu.h"
-MODULE_ALIAS("rcupdate");
#ifdef MODULE_PARAM_PREFIX
#undef MODULE_PARAM_PREFIX
#endif
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index aae08cedd75e..fac6492f0b98 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -581,6 +581,8 @@ static bool wake_up_full_nohz_cpu(int cpu)
* If needed we can still optimize that later with an
* empty IRQ.
*/
+ if (cpu_is_offline(cpu))
+ return true; /* Don't try to wake offline CPUs. */
if (tick_nohz_full_cpu(cpu)) {
if (cpu != smp_processor_id() ||
tick_nohz_tick_stopped())
@@ -591,6 +593,11 @@ static bool wake_up_full_nohz_cpu(int cpu)
return false;
}
+/*
+ * Wake up the specified CPU. If the CPU is going offline, it is the
+ * caller's responsibility to deal with the lost wakeup, for example,
+ * by hooking into the CPU_DEAD notifier like timers and hrtimers do.
+ */
void wake_up_nohz_cpu(int cpu)
{
if (!wake_up_full_nohz_cpu(cpu))
diff --git a/kernel/sched/cpufreq.c b/kernel/sched/cpufreq.c
index 1141954e73b4..dbc51442ecbc 100644
--- a/kernel/sched/cpufreq.c
+++ b/kernel/sched/cpufreq.c
@@ -33,7 +33,7 @@ DEFINE_PER_CPU(struct update_util_data *, cpufreq_update_util_data);
*/
void cpufreq_add_update_util_hook(int cpu, struct update_util_data *data,
void (*func)(struct update_util_data *data, u64 time,
- unsigned long util, unsigned long max))
+ unsigned int flags))
{
if (WARN_ON(!data || !func))
return;
diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c
index a84641b222c1..69e06898997d 100644
--- a/kernel/sched/cpufreq_schedutil.c
+++ b/kernel/sched/cpufreq_schedutil.c
@@ -12,7 +12,6 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/cpufreq.h>
-#include <linux/module.h>
#include <linux/slab.h>
#include <trace/events/power.h>
@@ -48,11 +47,14 @@ struct sugov_cpu {
struct sugov_policy *sg_policy;
unsigned int cached_raw_freq;
+ unsigned long iowait_boost;
+ unsigned long iowait_boost_max;
+ u64 last_update;
/* The fields below are only needed when sharing a policy. */
unsigned long util;
unsigned long max;
- u64 last_update;
+ unsigned int flags;
};
static DEFINE_PER_CPU(struct sugov_cpu, sugov_cpu);
@@ -144,24 +146,75 @@ static unsigned int get_next_freq(struct sugov_cpu *sg_cpu, unsigned long util,
return cpufreq_driver_resolve_freq(policy, freq);
}
+static void sugov_get_util(unsigned long *util, unsigned long *max)
+{
+ struct rq *rq = this_rq();
+ unsigned long cfs_max;
+
+ cfs_max = arch_scale_cpu_capacity(NULL, smp_processor_id());
+
+ *util = min(rq->cfs.avg.util_avg, cfs_max);
+ *max = cfs_max;
+}
+
+static void sugov_set_iowait_boost(struct sugov_cpu *sg_cpu, u64 time,
+ unsigned int flags)
+{
+ if (flags & SCHED_CPUFREQ_IOWAIT) {
+ sg_cpu->iowait_boost = sg_cpu->iowait_boost_max;
+ } else if (sg_cpu->iowait_boost) {
+ s64 delta_ns = time - sg_cpu->last_update;
+
+ /* Clear iowait_boost if the CPU apprears to have been idle. */
+ if (delta_ns > TICK_NSEC)
+ sg_cpu->iowait_boost = 0;
+ }
+}
+
+static void sugov_iowait_boost(struct sugov_cpu *sg_cpu, unsigned long *util,
+ unsigned long *max)
+{
+ unsigned long boost_util = sg_cpu->iowait_boost;
+ unsigned long boost_max = sg_cpu->iowait_boost_max;
+
+ if (!boost_util)
+ return;
+
+ if (*util * boost_max < *max * boost_util) {
+ *util = boost_util;
+ *max = boost_max;
+ }
+ sg_cpu->iowait_boost >>= 1;
+}
+
static void sugov_update_single(struct update_util_data *hook, u64 time,
- unsigned long util, unsigned long max)
+ unsigned int flags)
{
struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util);
struct sugov_policy *sg_policy = sg_cpu->sg_policy;
struct cpufreq_policy *policy = sg_policy->policy;
+ unsigned long util, max;
unsigned int next_f;
+ sugov_set_iowait_boost(sg_cpu, time, flags);
+ sg_cpu->last_update = time;
+
if (!sugov_should_update_freq(sg_policy, time))
return;
- next_f = util == ULONG_MAX ? policy->cpuinfo.max_freq :
- get_next_freq(sg_cpu, util, max);
+ if (flags & SCHED_CPUFREQ_RT_DL) {
+ next_f = policy->cpuinfo.max_freq;
+ } else {
+ sugov_get_util(&util, &max);
+ sugov_iowait_boost(sg_cpu, &util, &max);
+ next_f = get_next_freq(sg_cpu, util, max);
+ }
sugov_update_commit(sg_policy, time, next_f);
}
static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu,
- unsigned long util, unsigned long max)
+ unsigned long util, unsigned long max,
+ unsigned int flags)
{
struct sugov_policy *sg_policy = sg_cpu->sg_policy;
struct cpufreq_policy *policy = sg_policy->policy;
@@ -169,9 +222,11 @@ static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu,
u64 last_freq_update_time = sg_policy->last_freq_update_time;
unsigned int j;
- if (util == ULONG_MAX)
+ if (flags & SCHED_CPUFREQ_RT_DL)
return max_f;
+ sugov_iowait_boost(sg_cpu, &util, &max);
+
for_each_cpu(j, policy->cpus) {
struct sugov_cpu *j_sg_cpu;
unsigned long j_util, j_max;
@@ -186,41 +241,50 @@ static unsigned int sugov_next_freq_shared(struct sugov_cpu *sg_cpu,
* frequency update and the time elapsed between the last update
* of the CPU utilization and the last frequency update is long
* enough, don't take the CPU into account as it probably is
- * idle now.
+ * idle now (and clear iowait_boost for it).
*/
delta_ns = last_freq_update_time - j_sg_cpu->last_update;
- if (delta_ns > TICK_NSEC)
+ if (delta_ns > TICK_NSEC) {
+ j_sg_cpu->iowait_boost = 0;
continue;
-
- j_util = j_sg_cpu->util;
- if (j_util == ULONG_MAX)
+ }
+ if (j_sg_cpu->flags & SCHED_CPUFREQ_RT_DL)
return max_f;
+ j_util = j_sg_cpu->util;
j_max = j_sg_cpu->max;
if (j_util * max > j_max * util) {
util = j_util;
max = j_max;
}
+
+ sugov_iowait_boost(j_sg_cpu, &util, &max);
}
return get_next_freq(sg_cpu, util, max);
}
static void sugov_update_shared(struct update_util_data *hook, u64 time,
- unsigned long util, unsigned long max)
+ unsigned int flags)
{
struct sugov_cpu *sg_cpu = container_of(hook, struct sugov_cpu, update_util);
struct sugov_policy *sg_policy = sg_cpu->sg_policy;
+ unsigned long util, max;
unsigned int next_f;
+ sugov_get_util(&util, &max);
+
raw_spin_lock(&sg_policy->update_lock);
sg_cpu->util = util;
sg_cpu->max = max;
+ sg_cpu->flags = flags;
+
+ sugov_set_iowait_boost(sg_cpu, time, flags);
sg_cpu->last_update = time;
if (sugov_should_update_freq(sg_policy, time)) {
- next_f = sugov_next_freq_shared(sg_cpu, util, max);
+ next_f = sugov_next_freq_shared(sg_cpu, util, max, flags);
sugov_update_commit(sg_policy, time, next_f);
}
@@ -444,10 +508,13 @@ static int sugov_start(struct cpufreq_policy *policy)
sg_cpu->sg_policy = sg_policy;
if (policy_is_shared(policy)) {
- sg_cpu->util = ULONG_MAX;
+ sg_cpu->util = 0;
sg_cpu->max = 0;
+ sg_cpu->flags = SCHED_CPUFREQ_RT;
sg_cpu->last_update = 0;
sg_cpu->cached_raw_freq = 0;
+ sg_cpu->iowait_boost = 0;
+ sg_cpu->iowait_boost_max = policy->cpuinfo.max_freq;
cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util,
sugov_update_shared);
} else {
@@ -495,28 +562,15 @@ static struct cpufreq_governor schedutil_gov = {
.limits = sugov_limits,
};
-static int __init sugov_module_init(void)
-{
- return cpufreq_register_governor(&schedutil_gov);
-}
-
-static void __exit sugov_module_exit(void)
-{
- cpufreq_unregister_governor(&schedutil_gov);
-}
-
-MODULE_AUTHOR("Rafael J. Wysocki <rafael.j.wysocki@intel.com>");
-MODULE_DESCRIPTION("Utilization-based CPU frequency selection");
-MODULE_LICENSE("GPL");
-
#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_SCHEDUTIL
struct cpufreq_governor *cpufreq_default_governor(void)
{
return &schedutil_gov;
}
-
-fs_initcall(sugov_module_init);
-#else
-module_init(sugov_module_init);
#endif
-module_exit(sugov_module_exit);
+
+static int __init sugov_register(void)
+{
+ return cpufreq_register_governor(&schedutil_gov);
+}
+fs_initcall(sugov_register);
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 0c75bc656178..37e2449186c4 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -725,9 +725,8 @@ static void update_curr_dl(struct rq *rq)
return;
}
- /* kick cpufreq (see the comment in linux/cpufreq.h). */
- if (cpu_of(rq) == smp_processor_id())
- cpufreq_trigger_update(rq_clock(rq));
+ /* kick cpufreq (see the comment in kernel/sched/sched.h). */
+ cpufreq_update_this_cpu(rq, SCHED_CPUFREQ_DL);
schedstat_set(curr->se.statistics.exec_max,
max(curr->se.statistics.exec_max, delta_exec));
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 543b2f291152..502e95a6e927 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -2968,12 +2968,7 @@ static inline void update_tg_load_avg(struct cfs_rq *cfs_rq, int force) {}
static inline void cfs_rq_util_change(struct cfs_rq *cfs_rq)
{
- struct rq *rq = rq_of(cfs_rq);
- int cpu = cpu_of(rq);
-
- if (cpu == smp_processor_id() && &rq->cfs == cfs_rq) {
- unsigned long max = rq->cpu_capacity_orig;
-
+ if (&this_rq()->cfs == cfs_rq) {
/*
* There are a few boundary cases this might miss but it should
* get called often enough that that should (hopefully) not be
@@ -2990,8 +2985,7 @@ static inline void cfs_rq_util_change(struct cfs_rq *cfs_rq)
*
* See cpu_util().
*/
- cpufreq_update_util(rq_clock(rq),
- min(cfs_rq->avg.util_avg, max), max);
+ cpufreq_update_util(rq_of(cfs_rq), 0);
}
}
@@ -3252,10 +3246,7 @@ update_cfs_rq_load_avg(u64 now, struct cfs_rq *cfs_rq, bool update_freq)
static inline void update_load_avg(struct sched_entity *se, int not_used)
{
- struct cfs_rq *cfs_rq = cfs_rq_of(se);
- struct rq *rq = rq_of(cfs_rq);
-
- cpufreq_trigger_update(rq_clock(rq));
+ cpufreq_update_util(rq_of(cfs_rq_of(se)), 0);
}
static inline void
@@ -4540,6 +4531,14 @@ enqueue_task_fair(struct rq *rq, struct task_struct *p, int flags)
struct cfs_rq *cfs_rq;
struct sched_entity *se = &p->se;
+ /*
+ * If in_iowait is set, the code below may not trigger any cpufreq
+ * utilization updates, so do it here explicitly with the IOWAIT flag
+ * passed.
+ */
+ if (p->in_iowait)
+ cpufreq_update_this_cpu(rq, SCHED_CPUFREQ_IOWAIT);
+
for_each_sched_entity(se) {
if (se->on_rq)
break;
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index d5690b722691..2516b8df6dbb 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -957,9 +957,8 @@ static void update_curr_rt(struct rq *rq)
if (unlikely((s64)delta_exec <= 0))
return;
- /* Kick cpufreq (see the comment in linux/cpufreq.h). */
- if (cpu_of(rq) == smp_processor_id())
- cpufreq_trigger_update(rq_clock(rq));
+ /* Kick cpufreq (see the comment in kernel/sched/sched.h). */
+ cpufreq_update_this_cpu(rq, SCHED_CPUFREQ_RT);
schedstat_set(curr->se.statistics.exec_max,
max(curr->se.statistics.exec_max, delta_exec));
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 19b99869809d..58df5590d028 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -1765,27 +1765,13 @@ DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data);
/**
* cpufreq_update_util - Take a note about CPU utilization changes.
- * @time: Current time.
- * @util: Current utilization.
- * @max: Utilization ceiling.
+ * @rq: Runqueue to carry out the update for.
+ * @flags: Update reason flags.
*
- * This function is called by the scheduler on every invocation of
- * update_load_avg() on the CPU whose utilization is being updated.
+ * This function is called by the scheduler on the CPU whose utilization is
+ * being updated.
*
* It can only be called from RCU-sched read-side critical sections.
- */
-static inline void cpufreq_update_util(u64 time, unsigned long util, unsigned long max)
-{
- struct update_util_data *data;
-
- data = rcu_dereference_sched(*this_cpu_ptr(&cpufreq_update_util_data));
- if (data)
- data->func(data, time, util, max);
-}
-
-/**
- * cpufreq_trigger_update - Trigger CPU performance state evaluation if needed.
- * @time: Current time.
*
* The way cpufreq is currently arranged requires it to evaluate the CPU
* performance state (frequency/voltage) on a regular basis to prevent it from
@@ -1799,13 +1785,23 @@ static inline void cpufreq_update_util(u64 time, unsigned long util, unsigned lo
* but that really is a band-aid. Going forward it should be replaced with
* solutions targeted more specifically at RT and DL tasks.
*/
-static inline void cpufreq_trigger_update(u64 time)
+static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
+{
+ struct update_util_data *data;
+
+ data = rcu_dereference_sched(*this_cpu_ptr(&cpufreq_update_util_data));
+ if (data)
+ data->func(data, rq_clock(rq), flags);
+}
+
+static inline void cpufreq_update_this_cpu(struct rq *rq, unsigned int flags)
{
- cpufreq_update_util(time, ULONG_MAX, 0);
+ if (cpu_of(rq) == smp_processor_id())
+ cpufreq_update_util(rq, flags);
}
#else
-static inline void cpufreq_update_util(u64 time, unsigned long util, unsigned long max) {}
-static inline void cpufreq_trigger_update(u64 time) {}
+static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
+static inline void cpufreq_update_this_cpu(struct rq *rq, unsigned int flags) {}
#endif /* CONFIG_CPU_FREQ */
#ifdef arch_scale_freq_capacity
diff --git a/kernel/smp.c b/kernel/smp.c
index 3aa642d39c03..bba3b201668d 100644
--- a/kernel/smp.c
+++ b/kernel/smp.c
@@ -14,6 +14,7 @@
#include <linux/smp.h>
#include <linux/cpu.h>
#include <linux/sched.h>
+#include <linux/hypervisor.h>
#include "smpboot.h"
@@ -724,3 +725,54 @@ void wake_up_all_idle_cpus(void)
preempt_enable();
}
EXPORT_SYMBOL_GPL(wake_up_all_idle_cpus);
+
+/**
+ * smp_call_on_cpu - Call a function on a specific cpu
+ *
+ * Used to call a function on a specific cpu and wait for it to return.
+ * Optionally make sure the call is done on a specified physical cpu via vcpu
+ * pinning in order to support virtualized environments.
+ */
+struct smp_call_on_cpu_struct {
+ struct work_struct work;
+ struct completion done;
+ int (*func)(void *);
+ void *data;
+ int ret;
+ int cpu;
+};
+
+static void smp_call_on_cpu_callback(struct work_struct *work)
+{
+ struct smp_call_on_cpu_struct *sscs;
+
+ sscs = container_of(work, struct smp_call_on_cpu_struct, work);
+ if (sscs->cpu >= 0)
+ hypervisor_pin_vcpu(sscs->cpu);
+ sscs->ret = sscs->func(sscs->data);
+ if (sscs->cpu >= 0)
+ hypervisor_pin_vcpu(-1);
+
+ complete(&sscs->done);
+}
+
+int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par, bool phys)
+{
+ struct smp_call_on_cpu_struct sscs = {
+ .done = COMPLETION_INITIALIZER_ONSTACK(sscs.done),
+ .func = func,
+ .data = par,
+ .cpu = phys ? cpu : -1,
+ };
+
+ INIT_WORK_ONSTACK(&sscs.work, smp_call_on_cpu_callback);
+
+ if (cpu >= nr_cpu_ids || !cpu_online(cpu))
+ return -ENXIO;
+
+ queue_work_on(cpu, system_wq, &sscs.work);
+ wait_for_completion(&sscs.done);
+
+ return sscs.ret;
+}
+EXPORT_SYMBOL_GPL(smp_call_on_cpu);
diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c
index 082e71f17a58..ec9ab2f01489 100644
--- a/kernel/stop_machine.c
+++ b/kernel/stop_machine.c
@@ -20,7 +20,6 @@
#include <linux/kallsyms.h>
#include <linux/smpboot.h>
#include <linux/atomic.h>
-#include <linux/lglock.h>
#include <linux/nmi.h>
/*
@@ -47,13 +46,9 @@ struct cpu_stopper {
static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper);
static bool stop_machine_initialized = false;
-/*
- * Avoids a race between stop_two_cpus and global stop_cpus, where
- * the stoppers could get queued up in reverse order, leading to
- * system deadlock. Using an lglock means stop_two_cpus remains
- * relatively cheap.
- */
-DEFINE_STATIC_LGLOCK(stop_cpus_lock);
+/* static data for stop_cpus */
+static DEFINE_MUTEX(stop_cpus_mutex);
+static bool stop_cpus_in_progress;
static void cpu_stop_init_done(struct cpu_stop_done *done, unsigned int nr_todo)
{
@@ -235,14 +230,26 @@ static int cpu_stop_queue_two_works(int cpu1, struct cpu_stop_work *work1,
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);
+retry:
spin_lock_irq(&stopper1->lock);
spin_lock_nested(&stopper2->lock, SINGLE_DEPTH_NESTING);
err = -ENOENT;
if (!stopper1->enabled || !stopper2->enabled)
goto unlock;
+ /*
+ * Ensure that if we race with __stop_cpus() the stoppers won't get
+ * queued up in reverse order leading to system deadlock.
+ *
+ * We can't miss stop_cpus_in_progress if queue_stop_cpus_work() has
+ * queued a work on cpu1 but not on cpu2, we hold both locks.
+ *
+ * It can be falsely true but it is safe to spin until it is cleared,
+ * queue_stop_cpus_work() does everything under preempt_disable().
+ */
+ err = -EDEADLK;
+ if (unlikely(stop_cpus_in_progress))
+ goto unlock;
err = 0;
__cpu_stop_queue_work(stopper1, work1);
@@ -250,8 +257,12 @@ static int cpu_stop_queue_two_works(int cpu1, struct cpu_stop_work *work1,
unlock:
spin_unlock(&stopper2->lock);
spin_unlock_irq(&stopper1->lock);
- lg_double_unlock(&stop_cpus_lock, cpu1, cpu2);
+ if (unlikely(err == -EDEADLK)) {
+ while (stop_cpus_in_progress)
+ cpu_relax();
+ goto retry;
+ }
return err;
}
/**
@@ -321,9 +332,6 @@ bool stop_one_cpu_nowait(unsigned int cpu, cpu_stop_fn_t fn, void *arg,
return cpu_stop_queue_work(cpu, work_buf);
}
-/* static data for stop_cpus */
-static DEFINE_MUTEX(stop_cpus_mutex);
-
static bool queue_stop_cpus_work(const struct cpumask *cpumask,
cpu_stop_fn_t fn, void *arg,
struct cpu_stop_done *done)
@@ -337,7 +345,8 @@ static bool queue_stop_cpus_work(const struct cpumask *cpumask,
* preempted by a stopper which might wait for other stoppers
* to enter @fn which can lead to deadlock.
*/
- lg_global_lock(&stop_cpus_lock);
+ preempt_disable();
+ stop_cpus_in_progress = true;
for_each_cpu(cpu, cpumask) {
work = &per_cpu(cpu_stopper.stop_work, cpu);
work->fn = fn;
@@ -346,7 +355,8 @@ static bool queue_stop_cpus_work(const struct cpumask *cpumask,
if (cpu_stop_queue_work(cpu, work))
queued = true;
}
- lg_global_unlock(&stop_cpus_lock);
+ stop_cpus_in_progress = false;
+ preempt_enable();
return queued;
}
diff --git a/kernel/torture.c b/kernel/torture.c
index 75961b3decfe..0d887eb62856 100644
--- a/kernel/torture.c
+++ b/kernel/torture.c
@@ -43,6 +43,7 @@
#include <linux/stat.h>
#include <linux/slab.h>
#include <linux/trace_clock.h>
+#include <linux/ktime.h>
#include <asm/byteorder.h>
#include <linux/torture.h>
@@ -446,9 +447,8 @@ EXPORT_SYMBOL_GPL(torture_shuffle_cleanup);
* Variables for auto-shutdown. This allows "lights out" torture runs
* to be fully scripted.
*/
-static int shutdown_secs; /* desired test duration in seconds. */
static struct task_struct *shutdown_task;
-static unsigned long shutdown_time; /* jiffies to system shutdown. */
+static ktime_t shutdown_time; /* time to system shutdown. */
static void (*torture_shutdown_hook)(void);
/*
@@ -471,20 +471,20 @@ EXPORT_SYMBOL_GPL(torture_shutdown_absorb);
*/
static int torture_shutdown(void *arg)
{
- long delta;
- unsigned long jiffies_snap;
+ ktime_t ktime_snap;
VERBOSE_TOROUT_STRING("torture_shutdown task started");
- jiffies_snap = jiffies;
- while (ULONG_CMP_LT(jiffies_snap, shutdown_time) &&
+ ktime_snap = ktime_get();
+ while (ktime_before(ktime_snap, shutdown_time) &&
!torture_must_stop()) {
- delta = shutdown_time - jiffies_snap;
if (verbose)
pr_alert("%s" TORTURE_FLAG
- "torture_shutdown task: %lu jiffies remaining\n",
- torture_type, delta);
- schedule_timeout_interruptible(delta);
- jiffies_snap = jiffies;
+ "torture_shutdown task: %llu ms remaining\n",
+ torture_type,
+ ktime_ms_delta(shutdown_time, ktime_snap));
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_hrtimeout(&shutdown_time, HRTIMER_MODE_ABS);
+ ktime_snap = ktime_get();
}
if (torture_must_stop()) {
torture_kthread_stopping("torture_shutdown");
@@ -511,10 +511,9 @@ int torture_shutdown_init(int ssecs, void (*cleanup)(void))
{
int ret = 0;
- shutdown_secs = ssecs;
torture_shutdown_hook = cleanup;
- if (shutdown_secs > 0) {
- shutdown_time = jiffies + shutdown_secs * HZ;
+ if (ssecs > 0) {
+ shutdown_time = ktime_add(ktime_get(), ktime_set(ssecs, 0));
ret = torture_create_kthread(torture_shutdown, NULL,
shutdown_task);
}
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 7bc56762ca35..37824d98ae71 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4123,6 +4123,30 @@ static const char readme_msg[] =
"\t\t\t traces\n"
#endif
#endif /* CONFIG_STACK_TRACER */
+#ifdef CONFIG_KPROBE_EVENT
+ " kprobe_events\t\t- Add/remove/show the kernel dynamic events\n"
+ "\t\t\t Write into this file to define/undefine new trace events.\n"
+#endif
+#ifdef CONFIG_UPROBE_EVENT
+ " uprobe_events\t\t- Add/remove/show the userspace dynamic events\n"
+ "\t\t\t Write into this file to define/undefine new trace events.\n"
+#endif
+#if defined(CONFIG_KPROBE_EVENT) || defined(CONFIG_UPROBE_EVENT)
+ "\t accepts: event-definitions (one definition per line)\n"
+ "\t Format: p|r[:[<group>/]<event>] <place> [<args>]\n"
+ "\t -:[<group>/]<event>\n"
+#ifdef CONFIG_KPROBE_EVENT
+ "\t place: [<module>:]<symbol>[+<offset>]|<memaddr>\n"
+#endif
+#ifdef CONFIG_UPROBE_EVENT
+ "\t place: <path>:<offset>\n"
+#endif
+ "\t args: <name>=fetcharg[:type]\n"
+ "\t fetcharg: %<register>, @<address>, @<symbol>[+|-<offset>],\n"
+ "\t $stack<index>, $stack, $retval, $comm\n"
+ "\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string,\n"
+ "\t b<bit-width>@<bit-offset>/<container-size>\n"
+#endif
" events/\t\t- Directory containing all trace event subsystems:\n"
" enable\t\t- Write 0/1 to enable/disable tracing of all events\n"
" events/<system>/\t- Directory containing all trace events for <system>:\n"
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index 9aedb0b06683..eb6c9f1d3a93 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -253,6 +253,10 @@ static const struct fetch_type kprobes_fetch_type_table[] = {
ASSIGN_FETCH_TYPE(s16, u16, 1),
ASSIGN_FETCH_TYPE(s32, u32, 1),
ASSIGN_FETCH_TYPE(s64, u64, 1),
+ ASSIGN_FETCH_TYPE_ALIAS(x8, u8, u8, 0),
+ ASSIGN_FETCH_TYPE_ALIAS(x16, u16, u16, 0),
+ ASSIGN_FETCH_TYPE_ALIAS(x32, u32, u32, 0),
+ ASSIGN_FETCH_TYPE_ALIAS(x64, u64, u64, 0),
ASSIGN_FETCH_TYPE_END
};
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 74e80a582c28..8c0553d9afd3 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -36,24 +36,28 @@ const char *reserved_field_names[] = {
};
/* Printing in basic type function template */
-#define DEFINE_BASIC_PRINT_TYPE_FUNC(type, fmt) \
-int PRINT_TYPE_FUNC_NAME(type)(struct trace_seq *s, const char *name, \
+#define DEFINE_BASIC_PRINT_TYPE_FUNC(tname, type, fmt) \
+int PRINT_TYPE_FUNC_NAME(tname)(struct trace_seq *s, const char *name, \
void *data, void *ent) \
{ \
trace_seq_printf(s, " %s=" fmt, name, *(type *)data); \
return !trace_seq_has_overflowed(s); \
} \
-const char PRINT_TYPE_FMT_NAME(type)[] = fmt; \
-NOKPROBE_SYMBOL(PRINT_TYPE_FUNC_NAME(type));
-
-DEFINE_BASIC_PRINT_TYPE_FUNC(u8 , "0x%x")
-DEFINE_BASIC_PRINT_TYPE_FUNC(u16, "0x%x")
-DEFINE_BASIC_PRINT_TYPE_FUNC(u32, "0x%x")
-DEFINE_BASIC_PRINT_TYPE_FUNC(u64, "0x%Lx")
-DEFINE_BASIC_PRINT_TYPE_FUNC(s8, "%d")
-DEFINE_BASIC_PRINT_TYPE_FUNC(s16, "%d")
-DEFINE_BASIC_PRINT_TYPE_FUNC(s32, "%d")
-DEFINE_BASIC_PRINT_TYPE_FUNC(s64, "%Ld")
+const char PRINT_TYPE_FMT_NAME(tname)[] = fmt; \
+NOKPROBE_SYMBOL(PRINT_TYPE_FUNC_NAME(tname));
+
+DEFINE_BASIC_PRINT_TYPE_FUNC(u8, u8, "%u")
+DEFINE_BASIC_PRINT_TYPE_FUNC(u16, u16, "%u")
+DEFINE_BASIC_PRINT_TYPE_FUNC(u32, u32, "%u")
+DEFINE_BASIC_PRINT_TYPE_FUNC(u64, u64, "%Lu")
+DEFINE_BASIC_PRINT_TYPE_FUNC(s8, s8, "%d")
+DEFINE_BASIC_PRINT_TYPE_FUNC(s16, s16, "%d")
+DEFINE_BASIC_PRINT_TYPE_FUNC(s32, s32, "%d")
+DEFINE_BASIC_PRINT_TYPE_FUNC(s64, s64, "%Ld")
+DEFINE_BASIC_PRINT_TYPE_FUNC(x8, u8, "0x%x")
+DEFINE_BASIC_PRINT_TYPE_FUNC(x16, u16, "0x%x")
+DEFINE_BASIC_PRINT_TYPE_FUNC(x32, u32, "0x%x")
+DEFINE_BASIC_PRINT_TYPE_FUNC(x64, u64, "0x%Lx")
/* Print type function for string type */
int PRINT_TYPE_FUNC_NAME(string)(struct trace_seq *s, const char *name,
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 45400ca5ded1..0c0ae54d44c6 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -149,6 +149,11 @@ DECLARE_BASIC_PRINT_TYPE_FUNC(s8);
DECLARE_BASIC_PRINT_TYPE_FUNC(s16);
DECLARE_BASIC_PRINT_TYPE_FUNC(s32);
DECLARE_BASIC_PRINT_TYPE_FUNC(s64);
+DECLARE_BASIC_PRINT_TYPE_FUNC(x8);
+DECLARE_BASIC_PRINT_TYPE_FUNC(x16);
+DECLARE_BASIC_PRINT_TYPE_FUNC(x32);
+DECLARE_BASIC_PRINT_TYPE_FUNC(x64);
+
DECLARE_BASIC_PRINT_TYPE_FUNC(string);
#define FETCH_FUNC_NAME(method, type) fetch_##method##_##type
@@ -203,7 +208,7 @@ DEFINE_FETCH_##method(u32) \
DEFINE_FETCH_##method(u64)
/* Default (unsigned long) fetch type */
-#define __DEFAULT_FETCH_TYPE(t) u##t
+#define __DEFAULT_FETCH_TYPE(t) x##t
#define _DEFAULT_FETCH_TYPE(t) __DEFAULT_FETCH_TYPE(t)
#define DEFAULT_FETCH_TYPE _DEFAULT_FETCH_TYPE(BITS_PER_LONG)
#define DEFAULT_FETCH_TYPE_STR __stringify(DEFAULT_FETCH_TYPE)
@@ -234,6 +239,10 @@ ASSIGN_FETCH_FUNC(file_offset, ftype), \
#define ASSIGN_FETCH_TYPE(ptype, ftype, sign) \
__ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #ptype)
+/* If ptype is an alias of atype, use this macro (show atype in format) */
+#define ASSIGN_FETCH_TYPE_ALIAS(ptype, atype, ftype, sign) \
+ __ASSIGN_FETCH_TYPE(#ptype, ptype, ftype, sizeof(ftype), sign, #atype)
+
#define ASSIGN_FETCH_TYPE_END {}
#define FETCH_TYPE_STRING 0
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index c53485441c88..7a687320f867 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -211,6 +211,10 @@ static const struct fetch_type uprobes_fetch_type_table[] = {
ASSIGN_FETCH_TYPE(s16, u16, 1),
ASSIGN_FETCH_TYPE(s32, u32, 1),
ASSIGN_FETCH_TYPE(s64, u64, 1),
+ ASSIGN_FETCH_TYPE_ALIAS(x8, u8, u8, 0),
+ ASSIGN_FETCH_TYPE_ALIAS(x16, u16, u16, 0),
+ ASSIGN_FETCH_TYPE_ALIAS(x32, u32, u32, 0),
+ ASSIGN_FETCH_TYPE_ALIAS(x64, u64, u64, 0),
ASSIGN_FETCH_TYPE_END
};
diff --git a/kernel/up.c b/kernel/up.c
index 1760bf3d1463..ee81ac9af4ca 100644
--- a/kernel/up.c
+++ b/kernel/up.c
@@ -6,6 +6,7 @@
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/smp.h>
+#include <linux/hypervisor.h>
int smp_call_function_single(int cpu, void (*func) (void *info), void *info,
int wait)
@@ -82,3 +83,20 @@ void on_each_cpu_cond(bool (*cond_func)(int cpu, void *info),
preempt_enable();
}
EXPORT_SYMBOL(on_each_cpu_cond);
+
+int smp_call_on_cpu(unsigned int cpu, int (*func)(void *), void *par, bool phys)
+{
+ int ret;
+
+ if (cpu != 0)
+ return -ENXIO;
+
+ if (phys)
+ hypervisor_pin_vcpu(0);
+ ret = func(par);
+ if (phys)
+ hypervisor_pin_vcpu(-1);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(smp_call_on_cpu);
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