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-rw-r--r--kernel/exit.c2
-rw-r--r--kernel/fork.c10
-rw-r--r--kernel/futex.c3
-rw-r--r--kernel/hrtimer.c2
-rw-r--r--kernel/irq/handle.c1
-rw-r--r--kernel/lockdep.c20
-rw-r--r--kernel/mutex-debug.c1
-rw-r--r--kernel/panic.c3
-rw-r--r--kernel/perf_event.c282
-rw-r--r--kernel/power/suspend_test.c5
-rw-r--r--kernel/rcupdate.c140
-rw-r--r--kernel/rcutorture.c4
-rw-r--r--kernel/rcutree.c330
-rw-r--r--kernel/rcutree.h86
-rw-r--r--kernel/rcutree_plugin.h103
-rw-r--r--kernel/rcutree_trace.c4
-rw-r--r--kernel/sched.c33
-rw-r--r--kernel/time/tick-sched.c9
-rw-r--r--kernel/time/timekeeping.c1
-rw-r--r--kernel/trace/blktrace.c39
-rw-r--r--kernel/trace/ftrace.c2
-rw-r--r--kernel/trace/kmemtrace.c2
-rw-r--r--kernel/trace/ring_buffer.c12
-rw-r--r--kernel/trace/trace.c8
-rw-r--r--kernel/trace/trace_output.c5
-rw-r--r--kernel/trace/trace_syscalls.c4
-rw-r--r--kernel/workqueue.c18
27 files changed, 698 insertions, 431 deletions
diff --git a/kernel/exit.c b/kernel/exit.c
index 5859f598c951..e61891f80123 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -991,8 +991,6 @@ NORET_TYPE void do_exit(long code)
tsk->mempolicy = NULL;
#endif
#ifdef CONFIG_FUTEX
- if (unlikely(!list_empty(&tsk->pi_state_list)))
- exit_pi_state_list(tsk);
if (unlikely(current->pi_state_cache))
kfree(current->pi_state_cache);
#endif
diff --git a/kernel/fork.c b/kernel/fork.c
index 266c6af6ef1b..4c20fff8c13a 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -570,12 +570,18 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm)
/* Get rid of any futexes when releasing the mm */
#ifdef CONFIG_FUTEX
- if (unlikely(tsk->robust_list))
+ if (unlikely(tsk->robust_list)) {
exit_robust_list(tsk);
+ tsk->robust_list = NULL;
+ }
#ifdef CONFIG_COMPAT
- if (unlikely(tsk->compat_robust_list))
+ if (unlikely(tsk->compat_robust_list)) {
compat_exit_robust_list(tsk);
+ tsk->compat_robust_list = NULL;
+ }
#endif
+ if (unlikely(!list_empty(&tsk->pi_state_list)))
+ exit_pi_state_list(tsk);
#endif
/* Get rid of any cached register state */
diff --git a/kernel/futex.c b/kernel/futex.c
index b911adceb2c4..4949d336d88d 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -916,8 +916,8 @@ retry:
hb1 = hash_futex(&key1);
hb2 = hash_futex(&key2);
- double_lock_hb(hb1, hb2);
retry_private:
+ double_lock_hb(hb1, hb2);
op_ret = futex_atomic_op_inuser(op, uaddr2);
if (unlikely(op_ret < 0)) {
@@ -2117,7 +2117,6 @@ int handle_early_requeue_pi_wakeup(struct futex_hash_bucket *hb,
* Unqueue the futex_q and determine which it was.
*/
plist_del(&q->list, &q->list.plist);
- drop_futex_key_refs(&q->key);
if (timeout && !timeout->task)
ret = -ETIMEDOUT;
diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index 6d7020490f94..3e1c36e7998f 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -726,8 +726,6 @@ static int hrtimer_switch_to_hres(void)
/* "Retrigger" the interrupt to get things going */
retrigger_next_event(NULL);
local_irq_restore(flags);
- printk(KERN_DEBUG "Switched to high resolution mode on CPU %d\n",
- smp_processor_id());
return 1;
}
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index a81cf80554db..17c71bb565c6 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -11,6 +11,7 @@
*/
#include <linux/irq.h>
+#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/random.h>
diff --git a/kernel/lockdep.c b/kernel/lockdep.c
index 3815ac1d58b2..9af56723c096 100644
--- a/kernel/lockdep.c
+++ b/kernel/lockdep.c
@@ -142,6 +142,11 @@ static inline struct lock_class *hlock_class(struct held_lock *hlock)
#ifdef CONFIG_LOCK_STAT
static DEFINE_PER_CPU(struct lock_class_stats[MAX_LOCKDEP_KEYS], lock_stats);
+static inline u64 lockstat_clock(void)
+{
+ return cpu_clock(smp_processor_id());
+}
+
static int lock_point(unsigned long points[], unsigned long ip)
{
int i;
@@ -158,7 +163,7 @@ static int lock_point(unsigned long points[], unsigned long ip)
return i;
}
-static void lock_time_inc(struct lock_time *lt, s64 time)
+static void lock_time_inc(struct lock_time *lt, u64 time)
{
if (time > lt->max)
lt->max = time;
@@ -234,12 +239,12 @@ static void put_lock_stats(struct lock_class_stats *stats)
static void lock_release_holdtime(struct held_lock *hlock)
{
struct lock_class_stats *stats;
- s64 holdtime;
+ u64 holdtime;
if (!lock_stat)
return;
- holdtime = sched_clock() - hlock->holdtime_stamp;
+ holdtime = lockstat_clock() - hlock->holdtime_stamp;
stats = get_lock_stats(hlock_class(hlock));
if (hlock->read)
@@ -2792,7 +2797,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass,
hlock->references = references;
#ifdef CONFIG_LOCK_STAT
hlock->waittime_stamp = 0;
- hlock->holdtime_stamp = sched_clock();
+ hlock->holdtime_stamp = lockstat_clock();
#endif
if (check == 2 && !mark_irqflags(curr, hlock))
@@ -3322,7 +3327,7 @@ found_it:
if (hlock->instance != lock)
return;
- hlock->waittime_stamp = sched_clock();
+ hlock->waittime_stamp = lockstat_clock();
contention_point = lock_point(hlock_class(hlock)->contention_point, ip);
contending_point = lock_point(hlock_class(hlock)->contending_point,
@@ -3345,8 +3350,7 @@ __lock_acquired(struct lockdep_map *lock, unsigned long ip)
struct held_lock *hlock, *prev_hlock;
struct lock_class_stats *stats;
unsigned int depth;
- u64 now;
- s64 waittime = 0;
+ u64 now, waittime = 0;
int i, cpu;
depth = curr->lockdep_depth;
@@ -3374,7 +3378,7 @@ found_it:
cpu = smp_processor_id();
if (hlock->waittime_stamp) {
- now = sched_clock();
+ now = lockstat_clock();
waittime = now - hlock->waittime_stamp;
hlock->holdtime_stamp = now;
}
diff --git a/kernel/mutex-debug.c b/kernel/mutex-debug.c
index 50d022e5a560..ec815a960b5d 100644
--- a/kernel/mutex-debug.c
+++ b/kernel/mutex-debug.c
@@ -16,6 +16,7 @@
#include <linux/delay.h>
#include <linux/module.h>
#include <linux/poison.h>
+#include <linux/sched.h>
#include <linux/spinlock.h>
#include <linux/kallsyms.h>
#include <linux/interrupt.h>
diff --git a/kernel/panic.c b/kernel/panic.c
index bcdef26e3332..96b45d0b4ba5 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -90,6 +90,8 @@ NORET_TYPE void panic(const char * fmt, ...)
atomic_notifier_call_chain(&panic_notifier_list, 0, buf);
+ bust_spinlocks(0);
+
if (!panic_blink)
panic_blink = no_blink;
@@ -136,7 +138,6 @@ NORET_TYPE void panic(const char * fmt, ...)
mdelay(1);
i++;
}
- bust_spinlocks(0);
}
EXPORT_SYMBOL(panic);
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 0f86feb6db0c..9d0b5c665883 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -20,6 +20,7 @@
#include <linux/percpu.h>
#include <linux/ptrace.h>
#include <linux/vmstat.h>
+#include <linux/vmalloc.h>
#include <linux/hardirq.h>
#include <linux/rculist.h>
#include <linux/uaccess.h>
@@ -1030,14 +1031,10 @@ void __perf_event_sched_out(struct perf_event_context *ctx,
update_context_time(ctx);
perf_disable();
- if (ctx->nr_active) {
- list_for_each_entry(event, &ctx->group_list, group_entry) {
- if (event != event->group_leader)
- event_sched_out(event, cpuctx, ctx);
- else
- group_sched_out(event, cpuctx, ctx);
- }
- }
+ if (ctx->nr_active)
+ list_for_each_entry(event, &ctx->group_list, group_entry)
+ group_sched_out(event, cpuctx, ctx);
+
perf_enable();
out:
spin_unlock(&ctx->lock);
@@ -1258,12 +1255,8 @@ __perf_event_sched_in(struct perf_event_context *ctx,
if (event->cpu != -1 && event->cpu != cpu)
continue;
- if (event != event->group_leader)
- event_sched_in(event, cpuctx, ctx, cpu);
- else {
- if (group_can_go_on(event, cpuctx, 1))
- group_sched_in(event, cpuctx, ctx, cpu);
- }
+ if (group_can_go_on(event, cpuctx, 1))
+ group_sched_in(event, cpuctx, ctx, cpu);
/*
* If this pinned group hasn't been scheduled,
@@ -1291,15 +1284,9 @@ __perf_event_sched_in(struct perf_event_context *ctx,
if (event->cpu != -1 && event->cpu != cpu)
continue;
- if (event != event->group_leader) {
- if (event_sched_in(event, cpuctx, ctx, cpu))
+ if (group_can_go_on(event, cpuctx, can_add_hw))
+ if (group_sched_in(event, cpuctx, ctx, cpu))
can_add_hw = 0;
- } else {
- if (group_can_go_on(event, cpuctx, can_add_hw)) {
- if (group_sched_in(event, cpuctx, ctx, cpu))
- can_add_hw = 0;
- }
- }
}
perf_enable();
out:
@@ -2105,49 +2092,31 @@ unlock:
rcu_read_unlock();
}
-static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+static unsigned long perf_data_size(struct perf_mmap_data *data)
{
- struct perf_event *event = vma->vm_file->private_data;
- struct perf_mmap_data *data;
- int ret = VM_FAULT_SIGBUS;
-
- if (vmf->flags & FAULT_FLAG_MKWRITE) {
- if (vmf->pgoff == 0)
- ret = 0;
- return ret;
- }
-
- rcu_read_lock();
- data = rcu_dereference(event->data);
- if (!data)
- goto unlock;
-
- if (vmf->pgoff == 0) {
- vmf->page = virt_to_page(data->user_page);
- } else {
- int nr = vmf->pgoff - 1;
-
- if ((unsigned)nr > data->nr_pages)
- goto unlock;
+ return data->nr_pages << (PAGE_SHIFT + data->data_order);
+}
- if (vmf->flags & FAULT_FLAG_WRITE)
- goto unlock;
+#ifndef CONFIG_PERF_USE_VMALLOC
- vmf->page = virt_to_page(data->data_pages[nr]);
- }
+/*
+ * Back perf_mmap() with regular GFP_KERNEL-0 pages.
+ */
- get_page(vmf->page);
- vmf->page->mapping = vma->vm_file->f_mapping;
- vmf->page->index = vmf->pgoff;
+static struct page *
+perf_mmap_to_page(struct perf_mmap_data *data, unsigned long pgoff)
+{
+ if (pgoff > data->nr_pages)
+ return NULL;
- ret = 0;
-unlock:
- rcu_read_unlock();
+ if (pgoff == 0)
+ return virt_to_page(data->user_page);
- return ret;
+ return virt_to_page(data->data_pages[pgoff - 1]);
}
-static int perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
+static struct perf_mmap_data *
+perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
{
struct perf_mmap_data *data;
unsigned long size;
@@ -2172,19 +2141,10 @@ static int perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
goto fail_data_pages;
}
+ data->data_order = 0;
data->nr_pages = nr_pages;
- atomic_set(&data->lock, -1);
-
- if (event->attr.watermark) {
- data->watermark = min_t(long, PAGE_SIZE * nr_pages,
- event->attr.wakeup_watermark);
- }
- if (!data->watermark)
- data->watermark = max(PAGE_SIZE, PAGE_SIZE * nr_pages / 4);
- rcu_assign_pointer(event->data, data);
-
- return 0;
+ return data;
fail_data_pages:
for (i--; i >= 0; i--)
@@ -2196,7 +2156,7 @@ fail_user_page:
kfree(data);
fail:
- return -ENOMEM;
+ return NULL;
}
static void perf_mmap_free_page(unsigned long addr)
@@ -2207,28 +2167,169 @@ static void perf_mmap_free_page(unsigned long addr)
__free_page(page);
}
-static void __perf_mmap_data_free(struct rcu_head *rcu_head)
+static void perf_mmap_data_free(struct perf_mmap_data *data)
{
- struct perf_mmap_data *data;
int i;
- data = container_of(rcu_head, struct perf_mmap_data, rcu_head);
-
perf_mmap_free_page((unsigned long)data->user_page);
for (i = 0; i < data->nr_pages; i++)
perf_mmap_free_page((unsigned long)data->data_pages[i]);
+}
+
+#else
+
+/*
+ * Back perf_mmap() with vmalloc memory.
+ *
+ * Required for architectures that have d-cache aliasing issues.
+ */
+
+static struct page *
+perf_mmap_to_page(struct perf_mmap_data *data, unsigned long pgoff)
+{
+ if (pgoff > (1UL << data->data_order))
+ return NULL;
+
+ return vmalloc_to_page((void *)data->user_page + pgoff * PAGE_SIZE);
+}
+
+static void perf_mmap_unmark_page(void *addr)
+{
+ struct page *page = vmalloc_to_page(addr);
+
+ page->mapping = NULL;
+}
+
+static void perf_mmap_data_free_work(struct work_struct *work)
+{
+ struct perf_mmap_data *data;
+ void *base;
+ int i, nr;
+
+ data = container_of(work, struct perf_mmap_data, work);
+ nr = 1 << data->data_order;
+
+ base = data->user_page;
+ for (i = 0; i < nr + 1; i++)
+ perf_mmap_unmark_page(base + (i * PAGE_SIZE));
+
+ vfree(base);
+}
+static void perf_mmap_data_free(struct perf_mmap_data *data)
+{
+ schedule_work(&data->work);
+}
+
+static struct perf_mmap_data *
+perf_mmap_data_alloc(struct perf_event *event, int nr_pages)
+{
+ struct perf_mmap_data *data;
+ unsigned long size;
+ void *all_buf;
+
+ WARN_ON(atomic_read(&event->mmap_count));
+
+ size = sizeof(struct perf_mmap_data);
+ size += sizeof(void *);
+
+ data = kzalloc(size, GFP_KERNEL);
+ if (!data)
+ goto fail;
+
+ INIT_WORK(&data->work, perf_mmap_data_free_work);
+
+ all_buf = vmalloc_user((nr_pages + 1) * PAGE_SIZE);
+ if (!all_buf)
+ goto fail_all_buf;
+
+ data->user_page = all_buf;
+ data->data_pages[0] = all_buf + PAGE_SIZE;
+ data->data_order = ilog2(nr_pages);
+ data->nr_pages = 1;
+
+ return data;
+
+fail_all_buf:
+ kfree(data);
+
+fail:
+ return NULL;
+}
+
+#endif
+
+static int perf_mmap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
+{
+ struct perf_event *event = vma->vm_file->private_data;
+ struct perf_mmap_data *data;
+ int ret = VM_FAULT_SIGBUS;
+
+ if (vmf->flags & FAULT_FLAG_MKWRITE) {
+ if (vmf->pgoff == 0)
+ ret = 0;
+ return ret;
+ }
+
+ rcu_read_lock();
+ data = rcu_dereference(event->data);
+ if (!data)
+ goto unlock;
+
+ if (vmf->pgoff && (vmf->flags & FAULT_FLAG_WRITE))
+ goto unlock;
+
+ vmf->page = perf_mmap_to_page(data, vmf->pgoff);
+ if (!vmf->page)
+ goto unlock;
+
+ get_page(vmf->page);
+ vmf->page->mapping = vma->vm_file->f_mapping;
+ vmf->page->index = vmf->pgoff;
+
+ ret = 0;
+unlock:
+ rcu_read_unlock();
+
+ return ret;
+}
+
+static void
+perf_mmap_data_init(struct perf_event *event, struct perf_mmap_data *data)
+{
+ long max_size = perf_data_size(data);
+
+ atomic_set(&data->lock, -1);
+
+ if (event->attr.watermark) {
+ data->watermark = min_t(long, max_size,
+ event->attr.wakeup_watermark);
+ }
+
+ if (!data->watermark)
+ data->watermark = max_t(long, PAGE_SIZE, max_size / 2);
+
+
+ rcu_assign_pointer(event->data, data);
+}
+
+static void perf_mmap_data_free_rcu(struct rcu_head *rcu_head)
+{
+ struct perf_mmap_data *data;
+
+ data = container_of(rcu_head, struct perf_mmap_data, rcu_head);
+ perf_mmap_data_free(data);
kfree(data);
}
-static void perf_mmap_data_free(struct perf_event *event)
+static void perf_mmap_data_release(struct perf_event *event)
{
struct perf_mmap_data *data = event->data;
WARN_ON(atomic_read(&event->mmap_count));
rcu_assign_pointer(event->data, NULL);
- call_rcu(&data->rcu_head, __perf_mmap_data_free);
+ call_rcu(&data->rcu_head, perf_mmap_data_free_rcu);
}
static void perf_mmap_open(struct vm_area_struct *vma)
@@ -2244,11 +2345,12 @@ static void perf_mmap_close(struct vm_area_struct *vma)
WARN_ON_ONCE(event->ctx->parent_ctx);
if (atomic_dec_and_mutex_lock(&event->mmap_count, &event->mmap_mutex)) {
+ unsigned long size = perf_data_size(event->data);
struct user_struct *user = current_user();
- atomic_long_sub(event->data->nr_pages + 1, &user->locked_vm);
+ atomic_long_sub((size >> PAGE_SHIFT) + 1, &user->locked_vm);
vma->vm_mm->locked_vm -= event->data->nr_locked;
- perf_mmap_data_free(event);
+ perf_mmap_data_release(event);
mutex_unlock(&event->mmap_mutex);
}
}
@@ -2266,6 +2368,7 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
unsigned long user_locked, user_lock_limit;
struct user_struct *user = current_user();
unsigned long locked, lock_limit;
+ struct perf_mmap_data *data;
unsigned long vma_size;
unsigned long nr_pages;
long user_extra, extra;
@@ -2328,10 +2431,15 @@ static int perf_mmap(struct file *file, struct vm_area_struct *vma)
}
WARN_ON(event->data);
- ret = perf_mmap_data_alloc(event, nr_pages);
- if (ret)
+
+ data = perf_mmap_data_alloc(event, nr_pages);
+ ret = -ENOMEM;
+ if (!data)
goto unlock;
+ ret = 0;
+ perf_mmap_data_init(event, data);
+
atomic_set(&event->mmap_count, 1);
atomic_long_add(user_extra, &user->locked_vm);
vma->vm_mm->locked_vm += extra;
@@ -2519,7 +2627,7 @@ static bool perf_output_space(struct perf_mmap_data *data, unsigned long tail,
if (!data->writable)
return true;
- mask = (data->nr_pages << PAGE_SHIFT) - 1;
+ mask = perf_data_size(data) - 1;
offset = (offset - tail) & mask;
head = (head - tail) & mask;
@@ -2624,7 +2732,7 @@ void perf_output_copy(struct perf_output_handle *handle,
const void *buf, unsigned int len)
{
unsigned int pages_mask;
- unsigned int offset;
+ unsigned long offset;
unsigned int size;
void **pages;
@@ -2633,12 +2741,14 @@ void perf_output_copy(struct perf_output_handle *handle,
pages = handle->data->data_pages;
do {
- unsigned int page_offset;
+ unsigned long page_offset;
+ unsigned long page_size;
int nr;
nr = (offset >> PAGE_SHIFT) & pages_mask;
- page_offset = offset & (PAGE_SIZE - 1);
- size = min_t(unsigned int, PAGE_SIZE - page_offset, len);
+ page_size = 1UL << (handle->data->data_order + PAGE_SHIFT);
+ page_offset = offset & (page_size - 1);
+ size = min_t(unsigned int, page_size - page_offset, len);
memcpy(pages[nr] + page_offset, buf, size);
@@ -4781,9 +4891,7 @@ int perf_event_init_task(struct task_struct *child)
* We dont have to disable NMIs - we are only looking at
* the list, not manipulating it:
*/
- list_for_each_entry_rcu(event, &parent_ctx->event_list, event_entry) {
- if (event != event->group_leader)
- continue;
+ list_for_each_entry(event, &parent_ctx->group_list, group_entry) {
if (!event->attr.inherit) {
inherited_all = 0;
diff --git a/kernel/power/suspend_test.c b/kernel/power/suspend_test.c
index 17d8bb1acf9c..25596e450ac7 100644
--- a/kernel/power/suspend_test.c
+++ b/kernel/power/suspend_test.c
@@ -19,7 +19,7 @@
* The time it takes is system-specific though, so when we test this
* during system bootup we allow a LOT of time.
*/
-#define TEST_SUSPEND_SECONDS 5
+#define TEST_SUSPEND_SECONDS 10
static unsigned long suspend_test_start_time;
@@ -49,7 +49,8 @@ void suspend_test_finish(const char *label)
* has some performance issues. The stack dump of a WARN_ON
* is more likely to get the right attention than a printk...
*/
- WARN(msec > (TEST_SUSPEND_SECONDS * 1000), "Component: %s\n", label);
+ WARN(msec > (TEST_SUSPEND_SECONDS * 1000),
+ "Component: %s, time: %u\n", label, msec);
}
/*
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index 37ac45483082..400183346ad2 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -46,22 +46,15 @@
#include <linux/module.h>
#include <linux/kernel_stat.h>
-enum rcu_barrier {
- RCU_BARRIER_STD,
- RCU_BARRIER_BH,
- RCU_BARRIER_SCHED,
-};
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+static struct lock_class_key rcu_lock_key;
+struct lockdep_map rcu_lock_map =
+ STATIC_LOCKDEP_MAP_INIT("rcu_read_lock", &rcu_lock_key);
+EXPORT_SYMBOL_GPL(rcu_lock_map);
+#endif
-static DEFINE_PER_CPU(struct rcu_head, rcu_barrier_head) = {NULL};
-static atomic_t rcu_barrier_cpu_count;
-static DEFINE_MUTEX(rcu_barrier_mutex);
-static struct completion rcu_barrier_completion;
int rcu_scheduler_active __read_mostly;
-static atomic_t rcu_migrate_type_count = ATOMIC_INIT(0);
-static struct rcu_head rcu_migrate_head[3];
-static DECLARE_WAIT_QUEUE_HEAD(rcu_migrate_wq);
-
/*
* Awaken the corresponding synchronize_rcu() instance now that a
* grace period has elapsed.
@@ -164,129 +157,10 @@ void synchronize_rcu_bh(void)
}
EXPORT_SYMBOL_GPL(synchronize_rcu_bh);
-static void rcu_barrier_callback(struct rcu_head *notused)
-{
- if (atomic_dec_and_test(&rcu_barrier_cpu_count))
- complete(&rcu_barrier_completion);
-}
-
-/*
- * Called with preemption disabled, and from cross-cpu IRQ context.
- */
-static void rcu_barrier_func(void *type)
-{
- int cpu = smp_processor_id();
- struct rcu_head *head = &per_cpu(rcu_barrier_head, cpu);
-
- atomic_inc(&rcu_barrier_cpu_count);
- switch ((enum rcu_barrier)type) {
- case RCU_BARRIER_STD:
- call_rcu(head, rcu_barrier_callback);
- break;
- case RCU_BARRIER_BH:
- call_rcu_bh(head, rcu_barrier_callback);
- break;
- case RCU_BARRIER_SCHED:
- call_rcu_sched(head, rcu_barrier_callback);
- break;
- }
-}
-
-static inline void wait_migrated_callbacks(void)
-{
- wait_event(rcu_migrate_wq, !atomic_read(&rcu_migrate_type_count));
- smp_mb(); /* In case we didn't sleep. */
-}
-
-/*
- * Orchestrate the specified type of RCU barrier, waiting for all
- * RCU callbacks of the specified type to complete.
- */
-static void _rcu_barrier(enum rcu_barrier type)
-{
- BUG_ON(in_interrupt());
- /* Take cpucontrol mutex to protect against CPU hotplug */
- mutex_lock(&rcu_barrier_mutex);
- init_completion(&rcu_barrier_completion);
- /*
- * Initialize rcu_barrier_cpu_count to 1, then invoke
- * rcu_barrier_func() on each CPU, so that each CPU also has
- * incremented rcu_barrier_cpu_count. Only then is it safe to
- * decrement rcu_barrier_cpu_count -- otherwise the first CPU
- * might complete its grace period before all of the other CPUs
- * did their increment, causing this function to return too
- * early.
- */
- atomic_set(&rcu_barrier_cpu_count, 1);
- on_each_cpu(rcu_barrier_func, (void *)type, 1);
- if (atomic_dec_and_test(&rcu_barrier_cpu_count))
- complete(&rcu_barrier_completion);
- wait_for_completion(&rcu_barrier_completion);
- mutex_unlock(&rcu_barrier_mutex);
- wait_migrated_callbacks();
-}
-
-/**
- * rcu_barrier - Wait until all in-flight call_rcu() callbacks complete.
- */
-void rcu_barrier(void)
-{
- _rcu_barrier(RCU_BARRIER_STD);
-}
-EXPORT_SYMBOL_GPL(rcu_barrier);
-
-/**
- * rcu_barrier_bh - Wait until all in-flight call_rcu_bh() callbacks complete.
- */
-void rcu_barrier_bh(void)
-{
- _rcu_barrier(RCU_BARRIER_BH);
-}
-EXPORT_SYMBOL_GPL(rcu_barrier_bh);
-
-/**
- * rcu_barrier_sched - Wait for in-flight call_rcu_sched() callbacks.
- */
-void rcu_barrier_sched(void)
-{
- _rcu_barrier(RCU_BARRIER_SCHED);
-}
-EXPORT_SYMBOL_GPL(rcu_barrier_sched);
-
-static void rcu_migrate_callback(struct rcu_head *notused)
-{
- if (atomic_dec_and_test(&rcu_migrate_type_count))
- wake_up(&rcu_migrate_wq);
-}
-
-extern int rcu_cpu_notify(struct notifier_block *self,
- unsigned long action, void *hcpu);
-
static int __cpuinit rcu_barrier_cpu_hotplug(struct notifier_block *self,
unsigned long action, void *hcpu)
{
- rcu_cpu_notify(self, action, hcpu);
- if (action == CPU_DYING) {
- /*
- * preempt_disable() in on_each_cpu() prevents stop_machine(),
- * so when "on_each_cpu(rcu_barrier_func, (void *)type, 1);"
- * returns, all online cpus have queued rcu_barrier_func(),
- * and the dead cpu(if it exist) queues rcu_migrate_callback()s.
- *
- * These callbacks ensure _rcu_barrier() waits for all
- * RCU callbacks of the specified type to complete.
- */
- atomic_set(&rcu_migrate_type_count, 3);
- call_rcu_bh(rcu_migrate_head, rcu_migrate_callback);
- call_rcu_sched(rcu_migrate_head + 1, rcu_migrate_callback);
- call_rcu(rcu_migrate_head + 2, rcu_migrate_callback);
- } else if (action == CPU_DOWN_PREPARE) {
- /* Don't need to wait until next removal operation. */
- /* rcu_migrate_head is protected by cpu_add_remove_lock */
- wait_migrated_callbacks();
- }
-
- return NOTIFY_OK;
+ return rcu_cpu_notify(self, action, hcpu);
}
void __init rcu_init(void)
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 233768f21f97..697c0a0229d4 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -606,8 +606,6 @@ static struct rcu_torture_ops sched_ops_sync = {
.name = "sched_sync"
};
-extern int rcu_expedited_torture_stats(char *page);
-
static struct rcu_torture_ops sched_expedited_ops = {
.init = rcu_sync_torture_init,
.cleanup = NULL,
@@ -650,7 +648,7 @@ rcu_torture_writer(void *arg)
old_rp = rcu_torture_current;
rp->rtort_mbtest = 1;
rcu_assign_pointer(rcu_torture_current, rp);
- smp_wmb();
+ smp_wmb(); /* Mods to old_rp must follow rcu_assign_pointer() */
if (old_rp) {
i = old_rp->rtort_pipe_count;
if (i > RCU_TORTURE_PIPE_LEN)
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 52b06f6e158c..705f02ac7433 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -49,13 +49,6 @@
#include "rcutree.h"
-#ifdef CONFIG_DEBUG_LOCK_ALLOC
-static struct lock_class_key rcu_lock_key;
-struct lockdep_map rcu_lock_map =
- STATIC_LOCKDEP_MAP_INIT("rcu_read_lock", &rcu_lock_key);
-EXPORT_SYMBOL_GPL(rcu_lock_map);
-#endif
-
/* Data structures. */
#define RCU_STATE_INITIALIZER(name) { \
@@ -70,6 +63,9 @@ EXPORT_SYMBOL_GPL(rcu_lock_map);
.gpnum = -300, \
.completed = -300, \
.onofflock = __SPIN_LOCK_UNLOCKED(&name.onofflock), \
+ .orphan_cbs_list = NULL, \
+ .orphan_cbs_tail = &name.orphan_cbs_list, \
+ .orphan_qlen = 0, \
.fqslock = __SPIN_LOCK_UNLOCKED(&name.fqslock), \
.n_force_qs = 0, \
.n_force_qs_ngp = 0, \
@@ -81,24 +77,16 @@ DEFINE_PER_CPU(struct rcu_data, rcu_sched_data);
struct rcu_state rcu_bh_state = RCU_STATE_INITIALIZER(rcu_bh_state);
DEFINE_PER_CPU(struct rcu_data, rcu_bh_data);
-extern long rcu_batches_completed_sched(void);
-static struct rcu_node *rcu_get_root(struct rcu_state *rsp);
-static void cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp,
- struct rcu_node *rnp, unsigned long flags);
-static void cpu_quiet_msk_finish(struct rcu_state *rsp, unsigned long flags);
-#ifdef CONFIG_HOTPLUG_CPU
-static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp);
-#endif /* #ifdef CONFIG_HOTPLUG_CPU */
-static void __rcu_process_callbacks(struct rcu_state *rsp,
- struct rcu_data *rdp);
-static void __call_rcu(struct rcu_head *head,
- void (*func)(struct rcu_head *rcu),
- struct rcu_state *rsp);
-static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp);
-static void __cpuinit rcu_init_percpu_data(int cpu, struct rcu_state *rsp,
- int preemptable);
-#include "rcutree_plugin.h"
+/*
+ * Return true if an RCU grace period is in progress. The ACCESS_ONCE()s
+ * permit this function to be invoked without holding the root rcu_node
+ * structure's ->lock, but of course results can be subject to change.
+ */
+static int rcu_gp_in_progress(struct rcu_state *rsp)
+{
+ return ACCESS_ONCE(rsp->completed) != ACCESS_ONCE(rsp->gpnum);
+}
/*
* Note a quiescent state. Because we do not need to know
@@ -137,6 +125,10 @@ static int blimit = 10; /* Maximum callbacks per softirq. */
static int qhimark = 10000; /* If this many pending, ignore blimit. */
static int qlowmark = 100; /* Once only this many pending, use blimit. */
+module_param(blimit, int, 0);
+module_param(qhimark, int, 0);
+module_param(qlowmark, int, 0);
+
static void force_quiescent_state(struct rcu_state *rsp, int relaxed);
static int rcu_pending(int cpu);
@@ -173,9 +165,7 @@ cpu_has_callbacks_ready_to_invoke(struct rcu_data *rdp)
static int
cpu_needs_another_gp(struct rcu_state *rsp, struct rcu_data *rdp)
{
- /* ACCESS_ONCE() because we are accessing outside of lock. */
- return *rdp->nxttail[RCU_DONE_TAIL] &&
- ACCESS_ONCE(rsp->completed) == ACCESS_ONCE(rsp->gpnum);
+ return *rdp->nxttail[RCU_DONE_TAIL] && !rcu_gp_in_progress(rsp);
}
/*
@@ -369,7 +359,7 @@ static long dyntick_recall_completed(struct rcu_state *rsp)
/*
* Snapshot the specified CPU's dynticks counter so that we can later
* credit them with an implicit quiescent state. Return 1 if this CPU
- * is already in a quiescent state courtesy of dynticks idle mode.
+ * is in dynticks idle mode, which is an extended quiescent state.
*/
static int dyntick_save_progress_counter(struct rcu_data *rdp)
{
@@ -475,30 +465,34 @@ static void print_other_cpu_stall(struct rcu_state *rsp)
long delta;
unsigned long flags;
struct rcu_node *rnp = rcu_get_root(rsp);
- struct rcu_node *rnp_cur = rsp->level[NUM_RCU_LVLS - 1];
- struct rcu_node *rnp_end = &rsp->node[NUM_RCU_NODES];
/* Only let one CPU complain about others per time interval. */
spin_lock_irqsave(&rnp->lock, flags);
delta = jiffies - rsp->jiffies_stall;
- if (delta < RCU_STALL_RAT_DELAY || rsp->gpnum == rsp->completed) {
+ if (delta < RCU_STALL_RAT_DELAY || !rcu_gp_in_progress(rsp)) {
spin_unlock_irqrestore(&rnp->lock, flags);
return;
}
rsp->jiffies_stall = jiffies + RCU_SECONDS_TILL_STALL_RECHECK;
+
+ /*
+ * Now rat on any tasks that got kicked up to the root rcu_node
+ * due to CPU offlining.
+ */
+ rcu_print_task_stall(rnp);
spin_unlock_irqrestore(&rnp->lock, flags);
/* OK, time to rat on our buddy... */
printk(KERN_ERR "INFO: RCU detected CPU stalls:");
- for (; rnp_cur < rnp_end; rnp_cur++) {
+ rcu_for_each_leaf_node(rsp, rnp) {
rcu_print_task_stall(rnp);
- if (rnp_cur->qsmask == 0)
+ if (rnp->qsmask == 0)
continue;
- for (cpu = 0; cpu <= rnp_cur->grphi - rnp_cur->grplo; cpu++)
- if (rnp_cur->qsmask & (1UL << cpu))
- printk(" %d", rnp_cur->grplo + cpu);
+ for (cpu = 0; cpu <= rnp->grphi - rnp->grplo; cpu++)
+ if (rnp->qsmask & (1UL << cpu))
+ printk(" %d", rnp->grplo + cpu);
}
printk(" (detected by %d, t=%ld jiffies)\n",
smp_processor_id(), (long)(jiffies - rsp->gp_start));
@@ -537,8 +531,7 @@ static void check_cpu_stall(struct rcu_state *rsp, struct rcu_data *rdp)
/* We haven't checked in, so go dump stack. */
print_cpu_stall(rsp);
- } else if (rsp->gpnum != rsp->completed &&
- delta >= RCU_STALL_RAT_DELAY) {
+ } else if (rcu_gp_in_progress(rsp) && delta >= RCU_STALL_RAT_DELAY) {
/* They had two time units to dump stack, so complain. */
print_other_cpu_stall(rsp);
@@ -617,9 +610,15 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
note_new_gpnum(rsp, rdp);
/*
- * Because we are first, we know that all our callbacks will
- * be covered by this upcoming grace period, even the ones
- * that were registered arbitrarily recently.
+ * Because this CPU just now started the new grace period, we know
+ * that all of its callbacks will be covered by this upcoming grace
+ * period, even the ones that were registered arbitrarily recently.
+ * Therefore, advance all outstanding callbacks to RCU_WAIT_TAIL.
+ *
+ * Other CPUs cannot be sure exactly when the grace period started.
+ * Therefore, their recently registered callbacks must pass through
+ * an additional RCU_NEXT_READY stage, so that they will be handled
+ * by the next RCU grace period.
*/
rdp->nxttail[RCU_NEXT_READY_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
rdp->nxttail[RCU_WAIT_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
@@ -657,7 +656,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
* one corresponding to this CPU, due to the fact that we have
* irqs disabled.
*/
- for (rnp = &rsp->node[0]; rnp < &rsp->node[NUM_RCU_NODES]; rnp++) {
+ rcu_for_each_node_breadth_first(rsp, rnp) {
spin_lock(&rnp->lock); /* irqs already disabled. */
rcu_preempt_check_blocked_tasks(rnp);
rnp->qsmask = rnp->qsmaskinit;
@@ -703,9 +702,9 @@ rcu_process_gp_end(struct rcu_state *rsp, struct rcu_data *rdp)
* hold rnp->lock, as required by rcu_start_gp(), which will release it.
*/
static void cpu_quiet_msk_finish(struct rcu_state *rsp, unsigned long flags)
- __releases(rnp->lock)
+ __releases(rcu_get_root(rsp)->lock)
{
- WARN_ON_ONCE(rsp->completed == rsp->gpnum);
+ WARN_ON_ONCE(!rcu_gp_in_progress(rsp));
rsp->completed = rsp->gpnum;
rcu_process_gp_end(rsp, rsp->rda[smp_processor_id()]);
rcu_start_gp(rsp, flags); /* releases root node's rnp->lock. */
@@ -842,17 +841,63 @@ rcu_check_quiescent_state(struct rcu_state *rsp, struct rcu_data *rdp)
#ifdef CONFIG_HOTPLUG_CPU
/*
+ * Move a dying CPU's RCU callbacks to the ->orphan_cbs_list for the
+ * specified flavor of RCU. The callbacks will be adopted by the next
+ * _rcu_barrier() invocation or by the CPU_DEAD notifier, whichever
+ * comes first. Because this is invoked from the CPU_DYING notifier,
+ * irqs are already disabled.
+ */
+static void rcu_send_cbs_to_orphanage(struct rcu_state *rsp)
+{
+ int i;
+ struct rcu_data *rdp = rsp->rda[smp_processor_id()];
+
+ if (rdp->nxtlist == NULL)
+ return; /* irqs disabled, so comparison is stable. */
+ spin_lock(&rsp->onofflock); /* irqs already disabled. */
+ *rsp->orphan_cbs_tail = rdp->nxtlist;
+ rsp->orphan_cbs_tail = rdp->nxttail[RCU_NEXT_TAIL];
+ rdp->nxtlist = NULL;
+ for (i = 0; i < RCU_NEXT_SIZE; i++)
+ rdp->nxttail[i] = &rdp->nxtlist;
+ rsp->orphan_qlen += rdp->qlen;
+ rdp->qlen = 0;
+ spin_unlock(&rsp->onofflock); /* irqs remain disabled. */
+}
+
+/*
+ * Adopt previously orphaned RCU callbacks.
+ */
+static void rcu_adopt_orphan_cbs(struct rcu_state *rsp)
+{
+ unsigned long flags;
+ struct rcu_data *rdp;
+
+ spin_lock_irqsave(&rsp->onofflock, flags);
+ rdp = rsp->rda[smp_processor_id()];
+ if (rsp->orphan_cbs_list == NULL) {
+ spin_unlock_irqrestore(&rsp->onofflock, flags);
+ return;
+ }
+ *rdp->nxttail[RCU_NEXT_TAIL] = rsp->orphan_cbs_list;
+ rdp->nxttail[RCU_NEXT_TAIL] = rsp->orphan_cbs_tail;
+ rdp->qlen += rsp->orphan_qlen;
+ rsp->orphan_cbs_list = NULL;
+ rsp->orphan_cbs_tail = &rsp->orphan_cbs_list;
+ rsp->orphan_qlen = 0;
+ spin_unlock_irqrestore(&rsp->onofflock, flags);
+}
+
+/*
* Remove the outgoing CPU from the bitmasks in the rcu_node hierarchy
* and move all callbacks from the outgoing CPU to the current one.
*/
static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
{
- int i;
unsigned long flags;
long lastcomp;
unsigned long mask;
struct rcu_data *rdp = rsp->rda[cpu];
- struct rcu_data *rdp_me;
struct rcu_node *rnp;
/* Exclude any attempts to start a new grace period. */
@@ -875,32 +920,9 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
} while (rnp != NULL);
lastcomp = rsp->completed;
- spin_unlock(&rsp->onofflock); /* irqs remain disabled. */
+ spin_unlock_irqrestore(&rsp->onofflock, flags);
- /*
- * Move callbacks from the outgoing CPU to the running CPU.
- * Note that the outgoing CPU is now quiscent, so it is now
- * (uncharacteristically) safe to access its rcu_data structure.
- * Note also that we must carefully retain the order of the
- * outgoing CPU's callbacks in order for rcu_barrier() to work
- * correctly. Finally, note that we start all the callbacks
- * afresh, even those that have passed through a grace period
- * and are therefore ready to invoke. The theory is that hotplug
- * events are rare, and that if they are frequent enough to
- * indefinitely delay callbacks, you have far worse things to
- * be worrying about.
- */
- rdp_me = rsp->rda[smp_processor_id()];
- if (rdp->nxtlist != NULL) {
- *rdp_me->nxttail[RCU_NEXT_TAIL] = rdp->nxtlist;
- rdp_me->nxttail[RCU_NEXT_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
- rdp->nxtlist = NULL;
- for (i = 0; i < RCU_NEXT_SIZE; i++)
- rdp->nxttail[i] = &rdp->nxtlist;
- rdp_me->qlen += rdp->qlen;
- rdp->qlen = 0;
- }
- local_irq_restore(flags);
+ rcu_adopt_orphan_cbs(rsp);
}
/*
@@ -918,6 +940,14 @@ static void rcu_offline_cpu(int cpu)
#else /* #ifdef CONFIG_HOTPLUG_CPU */
+static void rcu_send_cbs_to_orphanage(struct rcu_state *rsp)
+{
+}
+
+static void rcu_adopt_orphan_cbs(struct rcu_state *rsp)
+{
+}
+
static void rcu_offline_cpu(int cpu)
{
}
@@ -1050,33 +1080,32 @@ static int rcu_process_dyntick(struct rcu_state *rsp, long lastcomp,
int cpu;
unsigned long flags;
unsigned long mask;
- struct rcu_node *rnp_cur = rsp->level[NUM_RCU_LVLS - 1];
- struct rcu_node *rnp_end = &rsp->node[NUM_RCU_NODES];
+ struct rcu_node *rnp;
- for (; rnp_cur < rnp_end; rnp_cur++) {
+ rcu_for_each_leaf_node(rsp, rnp) {
mask = 0;
- spin_lock_irqsave(&rnp_cur->lock, flags);
+ spin_lock_irqsave(&rnp->lock, flags);
if (rsp->completed != lastcomp) {
- spin_unlock_irqrestore(&rnp_cur->lock, flags);
+ spin_unlock_irqrestore(&rnp->lock, flags);
return 1;
}
- if (rnp_cur->qsmask == 0) {
- spin_unlock_irqrestore(&rnp_cur->lock, flags);
+ if (rnp->qsmask == 0) {
+ spin_unlock_irqrestore(&rnp->lock, flags);
continue;
}
- cpu = rnp_cur->grplo;
+ cpu = rnp->grplo;
bit = 1;
- for (; cpu <= rnp_cur->grphi; cpu++, bit <<= 1) {
- if ((rnp_cur->qsmask & bit) != 0 && f(rsp->rda[cpu]))
+ for (; cpu <= rnp->grphi; cpu++, bit <<= 1) {
+ if ((rnp->qsmask & bit) != 0 && f(rsp->rda[cpu]))
mask |= bit;
}
if (mask != 0 && rsp->completed == lastcomp) {
- /* cpu_quiet_msk() releases rnp_cur->lock. */
- cpu_quiet_msk(mask, rsp, rnp_cur, flags);
+ /* cpu_quiet_msk() releases rnp->lock. */
+ cpu_quiet_msk(mask, rsp, rnp, flags);
continue;
}
- spin_unlock_irqrestore(&rnp_cur->lock, flags);
+ spin_unlock_irqrestore(&rnp->lock, flags);
}
return 0;
}
@@ -1092,7 +1121,7 @@ static void force_quiescent_state(struct rcu_state *rsp, int relaxed)
struct rcu_node *rnp = rcu_get_root(rsp);
u8 signaled;
- if (ACCESS_ONCE(rsp->completed) == ACCESS_ONCE(rsp->gpnum))
+ if (!rcu_gp_in_progress(rsp))
return; /* No grace period in progress, nothing to force. */
if (!spin_trylock_irqsave(&rsp->fqslock, flags)) {
rsp->n_force_qs_lh++; /* Inexact, can lose counts. Tough! */
@@ -1251,7 +1280,7 @@ __call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu),
rdp->nxttail[RCU_NEXT_TAIL] = &head->next;
/* Start a new grace period if one not already started. */
- if (ACCESS_ONCE(rsp->completed) == ACCESS_ONCE(rsp->gpnum)) {
+ if (!rcu_gp_in_progress(rsp)) {
unsigned long nestflag;
struct rcu_node *rnp_root = rcu_get_root(rsp);
@@ -1331,7 +1360,7 @@ static int __rcu_pending(struct rcu_state *rsp, struct rcu_data *rdp)
}
/* Has an RCU GP gone long enough to send resched IPIs &c? */
- if (ACCESS_ONCE(rsp->completed) != ACCESS_ONCE(rsp->gpnum) &&
+ if (rcu_gp_in_progress(rsp) &&
((long)(ACCESS_ONCE(rsp->jiffies_force_qs) - jiffies) < 0)) {
rdp->n_rp_need_fqs++;
return 1;
@@ -1368,6 +1397,82 @@ int rcu_needs_cpu(int cpu)
rcu_preempt_needs_cpu(cpu);
}
+static DEFINE_PER_CPU(struct rcu_head, rcu_barrier_head) = {NULL};
+static atomic_t rcu_barrier_cpu_count;
+static DEFINE_MUTEX(rcu_barrier_mutex);
+static struct completion rcu_barrier_completion;
+
+static void rcu_barrier_callback(struct rcu_head *notused)
+{
+ if (atomic_dec_and_test(&rcu_barrier_cpu_count))
+ complete(&rcu_barrier_completion);
+}
+
+/*
+ * Called with preemption disabled, and from cross-cpu IRQ context.
+ */
+static void rcu_barrier_func(void *type)
+{
+ int cpu = smp_processor_id();
+ struct rcu_head *head = &per_cpu(rcu_barrier_head, cpu);
+ void (*call_rcu_func)(struct rcu_head *head,
+ void (*func)(struct rcu_head *head));
+
+ atomic_inc(&rcu_barrier_cpu_count);
+ call_rcu_func = type;
+ call_rcu_func(head, rcu_barrier_callback);
+}
+
+/*
+ * Orchestrate the specified type of RCU barrier, waiting for all
+ * RCU callbacks of the specified type to complete.
+ */
+static void _rcu_barrier(struct rcu_state *rsp,
+ void (*call_rcu_func)(struct rcu_head *head,
+ void (*func)(struct rcu_head *head)))
+{
+ BUG_ON(in_interrupt());
+ /* Take mutex to serialize concurrent rcu_barrier() requests. */
+ mutex_lock(&rcu_barrier_mutex);
+ init_completion(&rcu_barrier_completion);
+ /*
+ * Initialize rcu_barrier_cpu_count to 1, then invoke
+ * rcu_barrier_func() on each CPU, so that each CPU also has
+ * incremented rcu_barrier_cpu_count. Only then is it safe to
+ * decrement rcu_barrier_cpu_count -- otherwise the first CPU
+ * might complete its grace period before all of the other CPUs
+ * did their increment, causing this function to return too
+ * early.
+ */
+ atomic_set(&rcu_barrier_cpu_count, 1);
+ preempt_disable(); /* stop CPU_DYING from filling orphan_cbs_list */
+ rcu_adopt_orphan_cbs(rsp);
+ on_each_cpu(rcu_barrier_func, (void *)call_rcu_func, 1);
+ preempt_enable(); /* CPU_DYING can again fill orphan_cbs_list */
+ if (atomic_dec_and_test(&rcu_barrier_cpu_count))
+ complete(&rcu_barrier_completion);
+ wait_for_completion(&rcu_barrier_completion);
+ mutex_unlock(&rcu_barrier_mutex);
+}
+
+/**
+ * rcu_barrier_bh - Wait until all in-flight call_rcu_bh() callbacks complete.
+ */
+void rcu_barrier_bh(void)
+{
+ _rcu_barrier(&rcu_bh_state, call_rcu_bh);
+}
+EXPORT_SYMBOL_GPL(rcu_barrier_bh);
+
+/**
+ * rcu_barrier_sched - Wait for in-flight call_rcu_sched() callbacks.
+ */
+void rcu_barrier_sched(void)
+{
+ _rcu_barrier(&rcu_sched_state, call_rcu_sched);
+}
+EXPORT_SYMBOL_GPL(rcu_barrier_sched);
+
/*
* Do boot-time initialization of a CPU's per-CPU RCU data.
*/
@@ -1464,6 +1569,22 @@ int __cpuinit rcu_cpu_notify(struct notifier_block *self,
case CPU_UP_PREPARE_FROZEN:
rcu_online_cpu(cpu);
break;
+ case CPU_DYING:
+ case CPU_DYING_FROZEN:
+ /*
+ * preempt_disable() in _rcu_barrier() prevents stop_machine(),
+ * so when "on_each_cpu(rcu_barrier_func, (void *)type, 1);"
+ * returns, all online cpus have queued rcu_barrier_func().
+ * The dying CPU clears its cpu_online_mask bit and
+ * moves all of its RCU callbacks to ->orphan_cbs_list
+ * in the context of stop_machine(), so subsequent calls
+ * to _rcu_barrier() will adopt these callbacks and only
+ * then queue rcu_barrier_func() on all remaining CPUs.
+ */
+ rcu_send_cbs_to_orphanage(&rcu_bh_state);
+ rcu_send_cbs_to_orphanage(&rcu_sched_state);
+ rcu_preempt_send_cbs_to_orphanage();
+ break;
case CPU_DEAD:
case CPU_DEAD_FROZEN:
case CPU_UP_CANCELED:
@@ -1526,7 +1647,8 @@ static void __init rcu_init_one(struct rcu_state *rsp)
cpustride *= rsp->levelspread[i];
rnp = rsp->level[i];
for (j = 0; j < rsp->levelcnt[i]; j++, rnp++) {
- spin_lock_init(&rnp->lock);
+ if (rnp != rcu_get_root(rsp))
+ spin_lock_init(&rnp->lock);
rnp->gpnum = 0;
rnp->qsmask = 0;
rnp->qsmaskinit = 0;
@@ -1549,6 +1671,7 @@ static void __init rcu_init_one(struct rcu_state *rsp)
INIT_LIST_HEAD(&rnp->blocked_tasks[1]);
}
}
+ spin_lock_init(&rcu_get_root(rsp)->lock);
}
/*
@@ -1558,6 +1681,10 @@ static void __init rcu_init_one(struct rcu_state *rsp)
*/
#define RCU_INIT_FLAVOR(rsp, rcu_data) \
do { \
+ int i; \
+ int j; \
+ struct rcu_node *rnp; \
+ \
rcu_init_one(rsp); \
rnp = (rsp)->level[NUM_RCU_LVLS - 1]; \
j = 0; \
@@ -1570,31 +1697,8 @@ do { \
} \
} while (0)
-#ifdef CONFIG_TREE_PREEMPT_RCU
-
-void __init __rcu_init_preempt(void)
-{
- int i; /* All used by RCU_INIT_FLAVOR(). */
- int j;
- struct rcu_node *rnp;
-
- RCU_INIT_FLAVOR(&rcu_preempt_state, rcu_preempt_data);
-}
-
-#else /* #ifdef CONFIG_TREE_PREEMPT_RCU */
-
-void __init __rcu_init_preempt(void)
-{
-}
-
-#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */
-
void __init __rcu_init(void)
{
- int i; /* All used by RCU_INIT_FLAVOR(). */
- int j;
- struct rcu_node *rnp;
-
rcu_bootup_announce();
#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
printk(KERN_INFO "RCU-based detection of stalled CPUs is enabled.\n");
@@ -1605,6 +1709,4 @@ void __init __rcu_init(void)
open_softirq(RCU_SOFTIRQ, rcu_process_callbacks);
}
-module_param(blimit, int, 0);
-module_param(qhimark, int, 0);
-module_param(qlowmark, int, 0);
+#include "rcutree_plugin.h"
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index 8e8287a983c2..b40ac5706040 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -48,14 +48,14 @@
#elif NR_CPUS <= RCU_FANOUT_SQ
# define NUM_RCU_LVLS 2
# define NUM_RCU_LVL_0 1
-# define NUM_RCU_LVL_1 (((NR_CPUS) + RCU_FANOUT - 1) / RCU_FANOUT)
+# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT)
# define NUM_RCU_LVL_2 (NR_CPUS)
# define NUM_RCU_LVL_3 0
#elif NR_CPUS <= RCU_FANOUT_CUBE
# define NUM_RCU_LVLS 3
# define NUM_RCU_LVL_0 1
-# define NUM_RCU_LVL_1 (((NR_CPUS) + RCU_FANOUT_SQ - 1) / RCU_FANOUT_SQ)
-# define NUM_RCU_LVL_2 (((NR_CPUS) + (RCU_FANOUT) - 1) / (RCU_FANOUT))
+# define NUM_RCU_LVL_1 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT_SQ)
+# define NUM_RCU_LVL_2 DIV_ROUND_UP(NR_CPUS, RCU_FANOUT)
# define NUM_RCU_LVL_3 NR_CPUS
#else
# error "CONFIG_RCU_FANOUT insufficient for NR_CPUS"
@@ -79,15 +79,21 @@ struct rcu_dynticks {
* Definition for node within the RCU grace-period-detection hierarchy.
*/
struct rcu_node {
- spinlock_t lock;
+ spinlock_t lock; /* Root rcu_node's lock protects some */
+ /* rcu_state fields as well as following. */
long gpnum; /* Current grace period for this node. */
/* This will either be equal to or one */
/* behind the root rcu_node's gpnum. */
unsigned long qsmask; /* CPUs or groups that need to switch in */
/* order for current grace period to proceed.*/
+ /* In leaf rcu_node, each bit corresponds to */
+ /* an rcu_data structure, otherwise, each */
+ /* bit corresponds to a child rcu_node */
+ /* structure. */
unsigned long qsmaskinit;
/* Per-GP initialization for qsmask. */
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. */
int grphi; /* highest-numbered CPU or group here. */
u8 grpnum; /* CPU/group number for next level up. */
@@ -95,8 +101,23 @@ struct rcu_node {
struct rcu_node *parent;
struct list_head blocked_tasks[2];
/* Tasks blocked in RCU read-side critsect. */
+ /* Grace period number (->gpnum) x blocked */
+ /* by tasks on the (x & 0x1) element of the */
+ /* blocked_tasks[] array. */
} ____cacheline_internodealigned_in_smp;
+/*
+ * Do a full breadth-first scan of the rcu_node structures for the
+ * specified rcu_state structure.
+ */
+#define rcu_for_each_node_breadth_first(rsp, rnp) \
+ for ((rnp) = &(rsp)->node[0]; \
+ (rnp) < &(rsp)->node[NUM_RCU_NODES]; (rnp)++)
+
+#define rcu_for_each_leaf_node(rsp, rnp) \
+ for ((rnp) = (rsp)->level[NUM_RCU_LVLS - 1]; \
+ (rnp) < &(rsp)->node[NUM_RCU_NODES]; (rnp)++)
+
/* 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. */
@@ -126,19 +147,22 @@ struct rcu_data {
* Any of the partitions might be empty, in which case the
* pointer to that partition will be equal to the pointer for
* the following partition. When the list is empty, all of
- * the nxttail elements point to nxtlist, which is NULL.
+ * the nxttail elements point to the ->nxtlist pointer itself,
+ * which in that case is NULL.
*
- * [*nxttail[RCU_NEXT_READY_TAIL], NULL = *nxttail[RCU_NEXT_TAIL]):
- * Entries that might have arrived after current GP ended
- * [*nxttail[RCU_WAIT_TAIL], *nxttail[RCU_NEXT_READY_TAIL]):
- * Entries known to have arrived before current GP ended
- * [*nxttail[RCU_DONE_TAIL], *nxttail[RCU_WAIT_TAIL]):
- * Entries that batch # <= ->completed - 1: waiting for current GP
* [nxtlist, *nxttail[RCU_DONE_TAIL]):
* Entries that batch # <= ->completed
* The grace period for these entries has completed, and
* the other grace-period-completed entries may be moved
* here temporarily in rcu_process_callbacks().
+ * [*nxttail[RCU_DONE_TAIL], *nxttail[RCU_WAIT_TAIL]):
+ * Entries that batch # <= ->completed - 1: waiting for current GP
+ * [*nxttail[RCU_WAIT_TAIL], *nxttail[RCU_NEXT_READY_TAIL]):
+ * Entries known to have arrived before current GP ended
+ * [*nxttail[RCU_NEXT_READY_TAIL], *nxttail[RCU_NEXT_TAIL]):
+ * Entries that might have arrived after current GP ended
+ * Note that the value of *nxttail[RCU_NEXT_TAIL] will
+ * always be NULL, as this is the end of the list.
*/
struct rcu_head *nxtlist;
struct rcu_head **nxttail[RCU_NEXT_SIZE];
@@ -216,8 +240,19 @@ struct rcu_state {
/* Force QS state. */
long gpnum; /* Current gp number. */
long completed; /* # of last completed gp. */
+
+ /* End of fields guarded by root rcu_node's lock. */
+
spinlock_t onofflock; /* exclude on/offline and */
- /* starting new GP. */
+ /* starting new GP. Also */
+ /* protects the following */
+ /* orphan_cbs fields. */
+ struct rcu_head *orphan_cbs_list; /* list of rcu_head structs */
+ /* orphaned by all CPUs in */
+ /* a given leaf rcu_node */
+ /* going offline. */
+ struct rcu_head **orphan_cbs_tail; /* And tail pointer. */
+ long orphan_qlen; /* Number of orphaned cbs. */
spinlock_t fqslock; /* Only one task forcing */
/* quiescent states. */
unsigned long jiffies_force_qs; /* Time at which to invoke */
@@ -255,5 +290,30 @@ extern struct rcu_state rcu_preempt_state;
DECLARE_PER_CPU(struct rcu_data, rcu_preempt_data);
#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
-#endif /* #ifdef RCU_TREE_NONCORE */
+#else /* #ifdef RCU_TREE_NONCORE */
+
+/* Forward declarations for rcutree_plugin.h */
+static inline void rcu_bootup_announce(void);
+long rcu_batches_completed(void);
+static void rcu_preempt_note_context_switch(int cpu);
+static int rcu_preempted_readers(struct rcu_node *rnp);
+#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
+static void rcu_print_task_stall(struct rcu_node *rnp);
+#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp);
+#ifdef CONFIG_HOTPLUG_CPU
+static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
+ struct rcu_node *rnp,
+ struct rcu_data *rdp);
+static void rcu_preempt_offline_cpu(int cpu);
+#endif /* #ifdef CONFIG_HOTPLUG_CPU */
+static void rcu_preempt_check_callbacks(int cpu);
+static void rcu_preempt_process_callbacks(void);
+void call_rcu(struct rcu_head *head, void (*func)(struct rcu_head *rcu));
+static int rcu_preempt_pending(int cpu);
+static int rcu_preempt_needs_cpu(int cpu);
+static void __cpuinit rcu_preempt_init_percpu_data(int cpu);
+static void rcu_preempt_send_cbs_to_orphanage(void);
+static void __init __rcu_init_preempt(void);
+#endif /* #else #ifdef RCU_TREE_NONCORE */
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 1cee04f627eb..c0cb783aa16a 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -150,6 +150,16 @@ void __rcu_read_lock(void)
}
EXPORT_SYMBOL_GPL(__rcu_read_lock);
+/*
+ * Check for preempted RCU readers blocking the current grace period
+ * for the specified rcu_node structure. If the caller needs a reliable
+ * answer, it must hold the rcu_node's ->lock.
+ */
+static int rcu_preempted_readers(struct rcu_node *rnp)
+{
+ return !list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]);
+}
+
static void rcu_read_unlock_special(struct task_struct *t)
{
int empty;
@@ -196,7 +206,7 @@ static void rcu_read_unlock_special(struct task_struct *t)
break;
spin_unlock(&rnp->lock); /* irqs remain disabled. */
}
- empty = list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]);
+ empty = !rcu_preempted_readers(rnp);
list_del_init(&t->rcu_node_entry);
t->rcu_blocked_node = NULL;
@@ -207,7 +217,7 @@ static void rcu_read_unlock_special(struct task_struct *t)
* drop rnp->lock and restore irq.
*/
if (!empty && rnp->qsmask == 0 &&
- list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1])) {
+ !rcu_preempted_readers(rnp)) {
struct rcu_node *rnp_p;
if (rnp->parent == NULL) {
@@ -257,12 +267,12 @@ static void rcu_print_task_stall(struct rcu_node *rnp)
{
unsigned long flags;
struct list_head *lp;
- int phase = rnp->gpnum & 0x1;
+ int phase;
struct task_struct *t;
- if (!list_empty(&rnp->blocked_tasks[phase])) {
+ if (rcu_preempted_readers(rnp)) {
spin_lock_irqsave(&rnp->lock, flags);
- phase = rnp->gpnum & 0x1; /* re-read under lock. */
+ phase = rnp->gpnum & 0x1;
lp = &rnp->blocked_tasks[phase];
list_for_each_entry(t, lp, rcu_node_entry)
printk(" P%d", t->pid);
@@ -281,20 +291,10 @@ static void rcu_print_task_stall(struct rcu_node *rnp)
*/
static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
{
- WARN_ON_ONCE(!list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]));
+ WARN_ON_ONCE(rcu_preempted_readers(rnp));
WARN_ON_ONCE(rnp->qsmask);
}
-/*
- * Check for preempted RCU readers for the specified rcu_node structure.
- * If the caller needs a reliable answer, it must hold the rcu_node's
- * >lock.
- */
-static int rcu_preempted_readers(struct rcu_node *rnp)
-{
- return !list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]);
-}
-
#ifdef CONFIG_HOTPLUG_CPU
/*
@@ -410,6 +410,15 @@ static int rcu_preempt_needs_cpu(int cpu)
return !!per_cpu(rcu_preempt_data, cpu).nxtlist;
}
+/**
+ * rcu_barrier - Wait until all in-flight call_rcu() callbacks complete.
+ */
+void rcu_barrier(void)
+{
+ _rcu_barrier(&rcu_preempt_state, call_rcu);
+}
+EXPORT_SYMBOL_GPL(rcu_barrier);
+
/*
* Initialize preemptable RCU's per-CPU data.
*/
@@ -419,6 +428,22 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu)
}
/*
+ * Move preemptable RCU's callbacks to ->orphan_cbs_list.
+ */
+static void rcu_preempt_send_cbs_to_orphanage(void)
+{
+ rcu_send_cbs_to_orphanage(&rcu_preempt_state);
+}
+
+/*
+ * Initialize preemptable RCU's state structures.
+ */
+static void __init __rcu_init_preempt(void)
+{
+ RCU_INIT_FLAVOR(&rcu_preempt_state, rcu_preempt_data);
+}
+
+/*
* Check for a task exiting while in a preemptable-RCU read-side
* critical section, clean up if so. No need to issue warnings,
* as debug_check_no_locks_held() already does this if lockdep
@@ -461,6 +486,15 @@ static void rcu_preempt_note_context_switch(int cpu)
{
}
+/*
+ * Because preemptable RCU does not exist, there are never any preempted
+ * RCU readers.
+ */
+static int rcu_preempted_readers(struct rcu_node *rnp)
+{
+ return 0;
+}
+
#ifdef CONFIG_RCU_CPU_STALL_DETECTOR
/*
@@ -483,15 +517,6 @@ static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
WARN_ON_ONCE(rnp->qsmask);
}
-/*
- * Because preemptable RCU does not exist, there are never any preempted
- * RCU readers.
- */
-static int rcu_preempted_readers(struct rcu_node *rnp)
-{
- return 0;
-}
-
#ifdef CONFIG_HOTPLUG_CPU
/*
@@ -518,7 +543,7 @@ static void rcu_preempt_offline_cpu(int cpu)
* Because preemptable RCU does not exist, it never has any callbacks
* to check.
*/
-void rcu_preempt_check_callbacks(int cpu)
+static void rcu_preempt_check_callbacks(int cpu)
{
}
@@ -526,7 +551,7 @@ void rcu_preempt_check_callbacks(int cpu)
* Because preemptable RCU does not exist, it never has any callbacks
* to process.
*/
-void rcu_preempt_process_callbacks(void)
+static void rcu_preempt_process_callbacks(void)
{
}
@@ -556,6 +581,16 @@ static int rcu_preempt_needs_cpu(int cpu)
}
/*
+ * Because preemptable RCU does not exist, rcu_barrier() is just
+ * another name for rcu_barrier_sched().
+ */
+void rcu_barrier(void)
+{
+ rcu_barrier_sched();
+}
+EXPORT_SYMBOL_GPL(rcu_barrier);
+
+/*
* Because preemptable RCU does not exist, there is no per-CPU
* data to initialize.
*/
@@ -563,4 +598,18 @@ static void __cpuinit rcu_preempt_init_percpu_data(int cpu)
{
}
+/*
+ * Because there is no preemptable RCU, there are no callbacks to move.
+ */
+static void rcu_preempt_send_cbs_to_orphanage(void)
+{
+}
+
+/*
+ * Because preemptable RCU does not exist, it need not be initialized.
+ */
+static void __init __rcu_init_preempt(void)
+{
+}
+
#endif /* #else #ifdef CONFIG_TREE_PREEMPT_RCU */
diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c
index 179e6ad80dc0..4b31c779e62e 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -159,13 +159,13 @@ static void print_one_rcu_state(struct seq_file *m, struct rcu_state *rsp)
struct rcu_node *rnp;
seq_printf(m, "c=%ld g=%ld s=%d jfq=%ld j=%x "
- "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu\n",
+ "nfqs=%lu/nfqsng=%lu(%lu) fqlh=%lu oqlen=%ld\n",
rsp->completed, rsp->gpnum, rsp->signaled,
(long)(rsp->jiffies_force_qs - jiffies),
(int)(jiffies & 0xffff),
rsp->n_force_qs, rsp->n_force_qs_ngp,
rsp->n_force_qs - rsp->n_force_qs_ngp,
- rsp->n_force_qs_lh);
+ rsp->n_force_qs_lh, rsp->orphan_qlen);
for (rnp = &rsp->node[0]; rnp - &rsp->node[0] < NUM_RCU_NODES; rnp++) {
if (rnp->level != level) {
seq_puts(m, "\n");
diff --git a/kernel/sched.c b/kernel/sched.c
index 1535f3884b88..e88689522e66 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -676,6 +676,7 @@ inline void update_rq_clock(struct rq *rq)
/**
* runqueue_is_locked
+ * @cpu: the processor in question.
*
* Returns true if the current cpu runqueue is locked.
* This interface allows printk to be called with the runqueue lock
@@ -2311,7 +2312,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
{
int cpu, orig_cpu, this_cpu, success = 0;
unsigned long flags;
- struct rq *rq;
+ struct rq *rq, *orig_rq;
if (!sched_feat(SYNC_WAKEUPS))
wake_flags &= ~WF_SYNC;
@@ -2319,7 +2320,7 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
this_cpu = get_cpu();
smp_wmb();
- rq = task_rq_lock(p, &flags);
+ rq = orig_rq = task_rq_lock(p, &flags);
update_rq_clock(rq);
if (!(p->state & state))
goto out;
@@ -2350,6 +2351,10 @@ static int try_to_wake_up(struct task_struct *p, unsigned int state,
set_task_cpu(p, cpu);
rq = task_rq_lock(p, &flags);
+
+ if (rq != orig_rq)
+ update_rq_clock(rq);
+
WARN_ON(p->state != TASK_WAKING);
cpu = task_cpu(p);
@@ -2515,22 +2520,17 @@ void sched_fork(struct task_struct *p, int clone_flags)
__sched_fork(p);
/*
- * Make sure we do not leak PI boosting priority to the child.
- */
- p->prio = current->normal_prio;
-
- /*
* Revert to default priority/policy on fork if requested.
*/
if (unlikely(p->sched_reset_on_fork)) {
- if (p->policy == SCHED_FIFO || p->policy == SCHED_RR)
+ if (p->policy == SCHED_FIFO || p->policy == SCHED_RR) {
p->policy = SCHED_NORMAL;
-
- if (p->normal_prio < DEFAULT_PRIO)
- p->prio = DEFAULT_PRIO;
+ p->normal_prio = p->static_prio;
+ }
if (PRIO_TO_NICE(p->static_prio) < 0) {
p->static_prio = NICE_TO_PRIO(0);
+ p->normal_prio = p->static_prio;
set_load_weight(p);
}
@@ -2541,6 +2541,11 @@ void sched_fork(struct task_struct *p, int clone_flags)
p->sched_reset_on_fork = 0;
}
+ /*
+ * Make sure we do not leak PI boosting priority to the child.
+ */
+ p->prio = current->normal_prio;
+
if (!rt_prio(p->prio))
p->sched_class = &fair_sched_class;
@@ -2581,8 +2586,6 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
BUG_ON(p->state != TASK_RUNNING);
update_rq_clock(rq);
- p->prio = effective_prio(p);
-
if (!p->sched_class->task_new || !current->se.on_rq) {
activate_task(rq, p, 0);
} else {
@@ -3658,6 +3661,7 @@ static void update_group_power(struct sched_domain *sd, int cpu)
/**
* update_sg_lb_stats - Update sched_group's statistics for load balancing.
+ * @sd: The sched_domain whose statistics are to be updated.
* @group: sched_group whose statistics are to be updated.
* @this_cpu: Cpu for which load balance is currently performed.
* @idle: Idle status of this_cpu
@@ -6720,9 +6724,6 @@ EXPORT_SYMBOL(yield);
/*
* This task is about to go to sleep on IO. Increment rq->nr_iowait so
* that process accounting knows that this is a task in IO wait state.
- *
- * But don't do that if it is a deliberate, throttling IO wait (this task
- * has set its backing_dev_info: the queue against which it should throttle)
*/
void __sched io_schedule(void)
{
diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index e0f59a21c061..89aed5933ed4 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -231,6 +231,13 @@ void tick_nohz_stop_sched_tick(int inidle)
if (!inidle && !ts->inidle)
goto end;
+ /*
+ * Set ts->inidle unconditionally. Even if the system did not
+ * switch to NOHZ mode the cpu frequency governers rely on the
+ * update of the idle time accounting in tick_nohz_start_idle().
+ */
+ ts->inidle = 1;
+
now = tick_nohz_start_idle(ts);
/*
@@ -248,8 +255,6 @@ void tick_nohz_stop_sched_tick(int inidle)
if (unlikely(ts->nohz_mode == NOHZ_MODE_INACTIVE))
goto end;
- ts->inidle = 1;
-
if (need_resched())
goto end;
diff --git a/kernel/time/timekeeping.c b/kernel/time/timekeeping.c
index fb0f46fa1ecd..c3a4e2907eaa 100644
--- a/kernel/time/timekeeping.c
+++ b/kernel/time/timekeeping.c
@@ -13,6 +13,7 @@
#include <linux/percpu.h>
#include <linux/init.h>
#include <linux/mm.h>
+#include <linux/sched.h>
#include <linux/sysdev.h>
#include <linux/clocksource.h>
#include <linux/jiffies.h>
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 3eb159c277c8..d9d6206e0b14 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -856,6 +856,37 @@ static void blk_add_trace_remap(struct request_queue *q, struct bio *bio,
}
/**
+ * blk_add_trace_rq_remap - Add a trace for a request-remap operation
+ * @q: queue the io is for
+ * @rq: the source request
+ * @dev: target device
+ * @from: source sector
+ *
+ * Description:
+ * Device mapper remaps request to other devices.
+ * Add a trace for that action.
+ *
+ **/
+static void blk_add_trace_rq_remap(struct request_queue *q,
+ struct request *rq, dev_t dev,
+ sector_t from)
+{
+ struct blk_trace *bt = q->blk_trace;
+ struct blk_io_trace_remap r;
+
+ if (likely(!bt))
+ return;
+
+ r.device_from = cpu_to_be32(dev);
+ r.device_to = cpu_to_be32(disk_devt(rq->rq_disk));
+ r.sector_from = cpu_to_be64(from);
+
+ __blk_add_trace(bt, blk_rq_pos(rq), blk_rq_bytes(rq),
+ rq_data_dir(rq), BLK_TA_REMAP, !!rq->errors,
+ sizeof(r), &r);
+}
+
+/**
* blk_add_driver_data - Add binary message with driver-specific data
* @q: queue the io is for
* @rq: io request
@@ -922,10 +953,13 @@ static void blk_register_tracepoints(void)
WARN_ON(ret);
ret = register_trace_block_remap(blk_add_trace_remap);
WARN_ON(ret);
+ ret = register_trace_block_rq_remap(blk_add_trace_rq_remap);
+ WARN_ON(ret);
}
static void blk_unregister_tracepoints(void)
{
+ unregister_trace_block_rq_remap(blk_add_trace_rq_remap);
unregister_trace_block_remap(blk_add_trace_remap);
unregister_trace_block_split(blk_add_trace_split);
unregister_trace_block_unplug_io(blk_add_trace_unplug_io);
@@ -1657,6 +1691,11 @@ int blk_trace_init_sysfs(struct device *dev)
return sysfs_create_group(&dev->kobj, &blk_trace_attr_group);
}
+void blk_trace_remove_sysfs(struct device *dev)
+{
+ sysfs_remove_group(&dev->kobj, &blk_trace_attr_group);
+}
+
#endif /* CONFIG_BLK_DEV_IO_TRACE */
#ifdef CONFIG_EVENT_TRACING
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index b10c0d90a6ff..1ed514fe3a30 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -751,7 +751,7 @@ ftrace_profile_write(struct file *filp, const char __user *ubuf,
out:
mutex_unlock(&ftrace_profile_lock);
- filp->f_pos += cnt;
+ *ppos += cnt;
return cnt;
}
diff --git a/kernel/trace/kmemtrace.c b/kernel/trace/kmemtrace.c
index 81b1645c8549..a91da69f153a 100644
--- a/kernel/trace/kmemtrace.c
+++ b/kernel/trace/kmemtrace.c
@@ -501,7 +501,7 @@ static int __init init_kmem_tracer(void)
return 1;
}
- if (!register_tracer(&kmem_tracer)) {
+ if (register_tracer(&kmem_tracer) != 0) {
pr_warning("Warning: could not register the kmem tracer\n");
return 1;
}
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index d4ff01970547..3ffa502fb243 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -483,7 +483,7 @@ struct ring_buffer_iter {
/* Up this if you want to test the TIME_EXTENTS and normalization */
#define DEBUG_SHIFT 0
-static inline u64 rb_time_stamp(struct ring_buffer *buffer, int cpu)
+static inline u64 rb_time_stamp(struct ring_buffer *buffer)
{
/* shift to debug/test normalization and TIME_EXTENTS */
return buffer->clock() << DEBUG_SHIFT;
@@ -494,7 +494,7 @@ u64 ring_buffer_time_stamp(struct ring_buffer *buffer, int cpu)
u64 time;
preempt_disable_notrace();
- time = rb_time_stamp(buffer, cpu);
+ time = rb_time_stamp(buffer);
preempt_enable_no_resched_notrace();
return time;
@@ -599,7 +599,7 @@ static struct list_head *rb_list_head(struct list_head *list)
}
/*
- * rb_is_head_page - test if the give page is the head page
+ * rb_is_head_page - test if the given page is the head page
*
* Because the reader may move the head_page pointer, we can
* not trust what the head page is (it may be pointing to
@@ -1868,7 +1868,7 @@ rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,
* Nested commits always have zero deltas, so
* just reread the time stamp
*/
- *ts = rb_time_stamp(buffer, cpu_buffer->cpu);
+ *ts = rb_time_stamp(buffer);
next_page->page->time_stamp = *ts;
}
@@ -2111,7 +2111,7 @@ rb_reserve_next_event(struct ring_buffer *buffer,
if (RB_WARN_ON(cpu_buffer, ++nr_loops > 1000))
goto out_fail;
- ts = rb_time_stamp(cpu_buffer->buffer, cpu_buffer->cpu);
+ ts = rb_time_stamp(cpu_buffer->buffer);
/*
* Only the first commit can update the timestamp.
@@ -2681,7 +2681,7 @@ unsigned long ring_buffer_entries(struct ring_buffer *buffer)
EXPORT_SYMBOL_GPL(ring_buffer_entries);
/**
- * ring_buffer_overrun_cpu - get the number of overruns in buffer
+ * ring_buffer_overruns - get the number of overruns in buffer
* @buffer: The ring buffer
*
* Returns the total number of overruns in the ring buffer
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 026e715a0c7a..9d3067a62d43 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2440,7 +2440,7 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf,
return ret;
}
- filp->f_pos += cnt;
+ *ppos += cnt;
return cnt;
}
@@ -2582,7 +2582,7 @@ tracing_ctrl_write(struct file *filp, const char __user *ubuf,
}
mutex_unlock(&trace_types_lock);
- filp->f_pos += cnt;
+ *ppos += cnt;
return cnt;
}
@@ -2764,7 +2764,7 @@ tracing_set_trace_write(struct file *filp, const char __user *ubuf,
if (err)
return err;
- filp->f_pos += ret;
+ *ppos += ret;
return ret;
}
@@ -3299,7 +3299,7 @@ tracing_entries_write(struct file *filp, const char __user *ubuf,
}
}
- filp->f_pos += cnt;
+ *ppos += cnt;
/* If check pages failed, return ENOMEM */
if (tracing_disabled)
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index ed17565826b0..b6c12c6a1bcd 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -69,6 +69,9 @@ enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
* @s: trace sequence descriptor
* @fmt: printf format string
*
+ * It returns 0 if the trace oversizes the buffer's free
+ * space, 1 otherwise.
+ *
* The tracer may use either sequence operations or its own
* copy to user routines. To simplify formating of a trace
* trace_seq_printf is used to store strings into a special
@@ -95,7 +98,7 @@ trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
s->len += ret;
- return len;
+ return 1;
}
EXPORT_SYMBOL_GPL(trace_seq_printf);
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 8bda4bff2286..ddee9c593732 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -229,7 +229,7 @@ int syscall_exit_format(struct ftrace_event_call *call, struct trace_seq *s)
"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n"
"\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n",
SYSCALL_FIELD(int, nr),
- SYSCALL_FIELD(unsigned long, ret));
+ SYSCALL_FIELD(long, ret));
if (!ret)
return 0;
@@ -275,7 +275,7 @@ int syscall_exit_define_fields(struct ftrace_event_call *call)
if (ret)
return ret;
- ret = trace_define_field(call, SYSCALL_FIELD(unsigned long, ret), 0,
+ ret = trace_define_field(call, SYSCALL_FIELD(long, ret), 0,
FILTER_OTHER);
return ret;
diff --git a/kernel/workqueue.c b/kernel/workqueue.c
index addfe2df93b1..47cdd7e76f2b 100644
--- a/kernel/workqueue.c
+++ b/kernel/workqueue.c
@@ -640,6 +640,24 @@ int schedule_delayed_work(struct delayed_work *dwork,
EXPORT_SYMBOL(schedule_delayed_work);
/**
+ * flush_delayed_work - block until a dwork_struct's callback has terminated
+ * @dwork: the delayed work which is to be flushed
+ *
+ * Any timeout is cancelled, and any pending work is run immediately.
+ */
+void flush_delayed_work(struct delayed_work *dwork)
+{
+ if (del_timer_sync(&dwork->timer)) {
+ struct cpu_workqueue_struct *cwq;
+ cwq = wq_per_cpu(keventd_wq, get_cpu());
+ __queue_work(cwq, &dwork->work);
+ put_cpu();
+ }
+ flush_work(&dwork->work);
+}
+EXPORT_SYMBOL(flush_delayed_work);
+
+/**
* schedule_delayed_work_on - queue work in global workqueue on CPU after delay
* @cpu: cpu to use
* @dwork: job to be done
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