aboutsummaryrefslogtreecommitdiff
path: root/kernel
diff options
context:
space:
mode:
authorAlex Shi <alex.shi@linaro.org>2016-06-14 17:06:48 +0800
committerAlex Shi <alex.shi@linaro.org>2016-06-14 17:06:48 +0800
commit1beb6ea36b283c1dc34812c6ef9bf56a1e494f8c (patch)
tree539dc6f4b8c68f385a6457ef7b9d15570a0a8dcc /kernel
parent6c1be3bf831c5b1f2ba51425315287df2c350633 (diff)
parentb5076139991c6b12c62346d9880eec1d4227d99f (diff)
downloadlinux-linaro-stable-1beb6ea36b283c1dc34812c6ef9bf56a1e494f8c.tar.gz
Merge tag 'v3.18.35' into linux-linaro-lsk-v3.18
This is the 3.18.35 stable release
Diffstat (limited to 'kernel')
-rw-r--r--kernel/exit.c29
-rw-r--r--kernel/sched/proc.c11
-rw-r--r--kernel/trace/ring_buffer.c83
3 files changed, 68 insertions, 55 deletions
diff --git a/kernel/exit.c b/kernel/exit.c
index 2116aace6c85..654021d9f1b3 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -930,17 +930,28 @@ static int eligible_pid(struct wait_opts *wo, struct task_struct *p)
task_pid_type(p, wo->wo_type) == wo->wo_pid;
}
-static int eligible_child(struct wait_opts *wo, struct task_struct *p)
+static int
+eligible_child(struct wait_opts *wo, bool ptrace, struct task_struct *p)
{
if (!eligible_pid(wo, p))
return 0;
- /* Wait for all children (clone and not) if __WALL is set;
- * otherwise, wait for clone children *only* if __WCLONE is
- * set; otherwise, wait for non-clone children *only*. (Note:
- * A "clone" child here is one that reports to its parent
- * using a signal other than SIGCHLD.) */
- if (((p->exit_signal != SIGCHLD) ^ !!(wo->wo_flags & __WCLONE))
- && !(wo->wo_flags & __WALL))
+
+ /*
+ * Wait for all children (clone and not) if __WALL is set or
+ * if it is traced by us.
+ */
+ if (ptrace || (wo->wo_flags & __WALL))
+ return 1;
+
+ /*
+ * Otherwise, wait for clone children *only* if __WCLONE is set;
+ * otherwise, wait for non-clone children *only*.
+ *
+ * Note: a "clone" child here is one that reports to its parent
+ * using a signal other than SIGCHLD, or a non-leader thread which
+ * we can only see if it is traced by us.
+ */
+ if ((p->exit_signal != SIGCHLD) ^ !!(wo->wo_flags & __WCLONE))
return 0;
return 1;
@@ -1313,7 +1324,7 @@ static int wait_consider_task(struct wait_opts *wo, int ptrace,
if (unlikely(exit_state == EXIT_DEAD))
return 0;
- ret = eligible_child(wo, p);
+ ret = eligible_child(wo, ptrace, p);
if (!ret)
return ret;
diff --git a/kernel/sched/proc.c b/kernel/sched/proc.c
index 8ecd552fe4f2..09dfe51f89b5 100644
--- a/kernel/sched/proc.c
+++ b/kernel/sched/proc.c
@@ -97,10 +97,13 @@ long calc_load_fold_active(struct rq *this_rq)
static unsigned long
calc_load(unsigned long load, unsigned long exp, unsigned long active)
{
- load *= exp;
- load += active * (FIXED_1 - exp);
- load += 1UL << (FSHIFT - 1);
- return load >> FSHIFT;
+ unsigned long newload;
+
+ newload = load * exp + active * (FIXED_1 - exp);
+ if (active >= load)
+ newload += FIXED_1-1;
+
+ return newload / FIXED_1;
}
#ifdef CONFIG_NO_HZ_COMMON
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 0fc5cfedcc8c..d4588b08e07a 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -466,7 +466,8 @@ struct ring_buffer_per_cpu {
raw_spinlock_t reader_lock; /* serialize readers */
arch_spinlock_t lock;
struct lock_class_key lock_key;
- unsigned int nr_pages;
+ unsigned long nr_pages;
+ unsigned int current_context;
struct list_head *pages;
struct buffer_page *head_page; /* read from head */
struct buffer_page *tail_page; /* write to tail */
@@ -486,7 +487,7 @@ struct ring_buffer_per_cpu {
u64 write_stamp;
u64 read_stamp;
/* ring buffer pages to update, > 0 to add, < 0 to remove */
- int nr_pages_to_update;
+ long nr_pages_to_update;
struct list_head new_pages; /* new pages to add */
struct work_struct update_pages_work;
struct completion update_done;
@@ -1165,10 +1166,10 @@ static int rb_check_pages(struct ring_buffer_per_cpu *cpu_buffer)
return 0;
}
-static int __rb_allocate_pages(int nr_pages, struct list_head *pages, int cpu)
+static int __rb_allocate_pages(long nr_pages, struct list_head *pages, int cpu)
{
- int i;
struct buffer_page *bpage, *tmp;
+ long i;
for (i = 0; i < nr_pages; i++) {
struct page *page;
@@ -1205,7 +1206,7 @@ free_pages:
}
static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
- unsigned nr_pages)
+ unsigned long nr_pages)
{
LIST_HEAD(pages);
@@ -1230,7 +1231,7 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
}
static struct ring_buffer_per_cpu *
-rb_allocate_cpu_buffer(struct ring_buffer *buffer, int nr_pages, int cpu)
+rb_allocate_cpu_buffer(struct ring_buffer *buffer, long nr_pages, int cpu)
{
struct ring_buffer_per_cpu *cpu_buffer;
struct buffer_page *bpage;
@@ -1330,8 +1331,9 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
struct lock_class_key *key)
{
struct ring_buffer *buffer;
+ long nr_pages;
int bsize;
- int cpu, nr_pages;
+ int cpu;
/* keep it in its own cache line */
buffer = kzalloc(ALIGN(sizeof(*buffer), cache_line_size()),
@@ -1457,12 +1459,12 @@ static inline unsigned long rb_page_write(struct buffer_page *bpage)
}
static int
-rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned int nr_pages)
+rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned long nr_pages)
{
struct list_head *tail_page, *to_remove, *next_page;
struct buffer_page *to_remove_page, *tmp_iter_page;
struct buffer_page *last_page, *first_page;
- unsigned int nr_removed;
+ unsigned long nr_removed;
unsigned long head_bit;
int page_entries;
@@ -1679,7 +1681,7 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size,
int cpu_id)
{
struct ring_buffer_per_cpu *cpu_buffer;
- unsigned nr_pages;
+ unsigned long nr_pages;
int cpu, err = 0;
/*
@@ -1693,14 +1695,13 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size,
!cpumask_test_cpu(cpu_id, buffer->cpumask))
return size;
- size = DIV_ROUND_UP(size, BUF_PAGE_SIZE);
- size *= BUF_PAGE_SIZE;
+ nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE);
/* we need a minimum of two pages */
- if (size < BUF_PAGE_SIZE * 2)
- size = BUF_PAGE_SIZE * 2;
+ if (nr_pages < 2)
+ nr_pages = 2;
- nr_pages = DIV_ROUND_UP(size, BUF_PAGE_SIZE);
+ size = nr_pages * BUF_PAGE_SIZE;
/*
* Don't succeed if resizing is disabled, as a reader might be
@@ -2680,11 +2681,11 @@ rb_reserve_next_event(struct ring_buffer *buffer,
* just so happens that it is the same bit corresponding to
* the current context.
*/
-static DEFINE_PER_CPU(unsigned int, current_context);
-static __always_inline int trace_recursive_lock(void)
+static __always_inline int
+trace_recursive_lock(struct ring_buffer_per_cpu *cpu_buffer)
{
- unsigned int val = __this_cpu_read(current_context);
+ unsigned int val = cpu_buffer->current_context;
int bit;
if (in_interrupt()) {
@@ -2701,23 +2702,21 @@ static __always_inline int trace_recursive_lock(void)
return 1;
val |= (1 << bit);
- __this_cpu_write(current_context, val);
+ cpu_buffer->current_context = val;
return 0;
}
-static __always_inline void trace_recursive_unlock(void)
+static __always_inline void
+trace_recursive_unlock(struct ring_buffer_per_cpu *cpu_buffer)
{
- unsigned int val = __this_cpu_read(current_context);
-
- val &= val & (val - 1);
- __this_cpu_write(current_context, val);
+ cpu_buffer->current_context &= cpu_buffer->current_context - 1;
}
#else
-#define trace_recursive_lock() (0)
-#define trace_recursive_unlock() do { } while (0)
+#define trace_recursive_lock(cpu_buffer) (0)
+#define trace_recursive_unlock(cpu_buffer) do { } while (0)
#endif
@@ -2749,35 +2748,34 @@ ring_buffer_lock_reserve(struct ring_buffer *buffer, unsigned long length)
/* If we are tracing schedule, we don't want to recurse */
preempt_disable_notrace();
- if (atomic_read(&buffer->record_disabled))
- goto out_nocheck;
-
- if (trace_recursive_lock())
- goto out_nocheck;
+ if (unlikely(atomic_read(&buffer->record_disabled)))
+ goto out;
cpu = raw_smp_processor_id();
- if (!cpumask_test_cpu(cpu, buffer->cpumask))
+ if (unlikely(!cpumask_test_cpu(cpu, buffer->cpumask)))
goto out;
cpu_buffer = buffer->buffers[cpu];
- if (atomic_read(&cpu_buffer->record_disabled))
+ if (unlikely(atomic_read(&cpu_buffer->record_disabled)))
goto out;
- if (length > BUF_MAX_DATA_SIZE)
+ if (unlikely(length > BUF_MAX_DATA_SIZE))
+ goto out;
+
+ if (unlikely(trace_recursive_lock(cpu_buffer)))
goto out;
event = rb_reserve_next_event(buffer, cpu_buffer, length);
if (!event)
- goto out;
+ goto out_unlock;
return event;
+ out_unlock:
+ trace_recursive_unlock(cpu_buffer);
out:
- trace_recursive_unlock();
-
- out_nocheck:
preempt_enable_notrace();
return NULL;
}
@@ -2867,7 +2865,7 @@ int ring_buffer_unlock_commit(struct ring_buffer *buffer,
rb_wakeups(buffer, cpu_buffer);
- trace_recursive_unlock();
+ trace_recursive_unlock(cpu_buffer);
preempt_enable_notrace();
@@ -2978,7 +2976,7 @@ void ring_buffer_discard_commit(struct ring_buffer *buffer,
out:
rb_end_commit(cpu_buffer);
- trace_recursive_unlock();
+ trace_recursive_unlock(cpu_buffer);
preempt_enable_notrace();
@@ -4655,8 +4653,9 @@ static int rb_cpu_notify(struct notifier_block *self,
struct ring_buffer *buffer =
container_of(self, struct ring_buffer, cpu_notify);
long cpu = (long)hcpu;
- int cpu_i, nr_pages_same;
- unsigned int nr_pages;
+ long nr_pages_same;
+ int cpu_i;
+ unsigned long nr_pages;
switch (action) {
case CPU_UP_PREPARE: