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-rw-r--r--kernel/sched.c41
1 files changed, 20 insertions, 21 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 2b2b780939c9..15ce772a471a 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -225,7 +225,8 @@ struct rq {
unsigned long nr_uninterruptible;
unsigned long expired_timestamp;
- unsigned long long timestamp_last_tick;
+ /* Cached timestamp set by update_cpu_clock() */
+ unsigned long long most_recent_timestamp;
struct task_struct *curr, *idle;
unsigned long next_balance;
struct mm_struct *prev_mm;
@@ -944,8 +945,8 @@ static void activate_task(struct task_struct *p, struct rq *rq, int local)
if (!local) {
/* Compensate for drifting sched_clock */
struct rq *this_rq = this_rq();
- now = (now - this_rq->timestamp_last_tick)
- + rq->timestamp_last_tick;
+ now = (now - this_rq->most_recent_timestamp)
+ + rq->most_recent_timestamp;
}
#endif
@@ -1689,8 +1690,8 @@ void fastcall wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
* Not the local CPU - must adjust timestamp. This should
* get optimised away in the !CONFIG_SMP case.
*/
- p->timestamp = (p->timestamp - this_rq->timestamp_last_tick)
- + rq->timestamp_last_tick;
+ p->timestamp = (p->timestamp - this_rq->most_recent_timestamp)
+ + rq->most_recent_timestamp;
__activate_task(p, rq);
if (TASK_PREEMPTS_CURR(p, rq))
resched_task(rq->curr);
@@ -2068,8 +2069,8 @@ static void pull_task(struct rq *src_rq, struct prio_array *src_array,
set_task_cpu(p, this_cpu);
inc_nr_running(p, this_rq);
enqueue_task(p, this_array);
- p->timestamp = (p->timestamp - src_rq->timestamp_last_tick)
- + this_rq->timestamp_last_tick;
+ p->timestamp = (p->timestamp - src_rq->most_recent_timestamp)
+ + this_rq->most_recent_timestamp;
/*
* Note that idle threads have a prio of MAX_PRIO, for this test
* to be always true for them.
@@ -2105,10 +2106,15 @@ int can_migrate_task(struct task_struct *p, struct rq *rq, int this_cpu,
* 2) too many balance attempts have failed.
*/
- if (sd->nr_balance_failed > sd->cache_nice_tries)
+ if (sd->nr_balance_failed > sd->cache_nice_tries) {
+#ifdef CONFIG_SCHEDSTATS
+ if (task_hot(p, rq->most_recent_timestamp, sd))
+ schedstat_inc(sd, lb_hot_gained[idle]);
+#endif
return 1;
+ }
- if (task_hot(p, rq->timestamp_last_tick, sd))
+ if (task_hot(p, rq->most_recent_timestamp, sd))
return 0;
return 1;
}
@@ -2206,11 +2212,6 @@ skip_queue:
goto skip_bitmap;
}
-#ifdef CONFIG_SCHEDSTATS
- if (task_hot(tmp, busiest->timestamp_last_tick, sd))
- schedstat_inc(sd, lb_hot_gained[idle]);
-#endif
-
pull_task(busiest, array, tmp, this_rq, dst_array, this_cpu);
pulled++;
rem_load_move -= tmp->load_weight;
@@ -2971,7 +2972,8 @@ EXPORT_PER_CPU_SYMBOL(kstat);
static inline void
update_cpu_clock(struct task_struct *p, struct rq *rq, unsigned long long now)
{
- p->sched_time += now - max(p->timestamp, rq->timestamp_last_tick);
+ p->sched_time += now - p->last_ran;
+ p->last_ran = rq->most_recent_timestamp = now;
}
/*
@@ -2984,8 +2986,7 @@ unsigned long long current_sched_time(const struct task_struct *p)
unsigned long flags;
local_irq_save(flags);
- ns = max(p->timestamp, task_rq(p)->timestamp_last_tick);
- ns = p->sched_time + sched_clock() - ns;
+ ns = p->sched_time + sched_clock() - p->last_ran;
local_irq_restore(flags);
return ns;
@@ -3176,8 +3177,6 @@ void scheduler_tick(void)
update_cpu_clock(p, rq, now);
- rq->timestamp_last_tick = now;
-
if (p == rq->idle)
/* Task on the idle queue */
wake_priority_sleeper(rq);
@@ -5032,8 +5031,8 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu)
* afterwards, and pretending it was a local activate.
* This way is cleaner and logically correct.
*/
- p->timestamp = p->timestamp - rq_src->timestamp_last_tick
- + rq_dest->timestamp_last_tick;
+ p->timestamp = p->timestamp - rq_src->most_recent_timestamp
+ + rq_dest->most_recent_timestamp;
deactivate_task(p, rq_src);
__activate_task(p, rq_dest);
if (TASK_PREEMPTS_CURR(p, rq_dest))