diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2017-02-21 14:40:35 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2017-03-16 09:46:24 +0100 |
| commit | bce4dc80c66ad355c74e876c82ce371020754627 (patch) | |
| tree | 94a1afef37ef4e07aa903198bbed8f79a59d10df /kernel/sched/core.c | |
| parent | 77558e4d01ac0c7fa8cb1af4a61c2ab508d79f30 (diff) | |
| download | blackbird-obmc-linux-bce4dc80c66ad355c74e876c82ce371020754627.tar.gz blackbird-obmc-linux-bce4dc80c66ad355c74e876c82ce371020754627.zip | |
sched/core: Simplify update_rq_clock() in __schedule()
Instead of relying on deactivate_task() to call update_rq_clock() and
handling the case where it didn't happen (task_on_rq_queued),
unconditionally do update_rq_clock() and skip any further updates.
This also avoids a double update on deactivate_task() + ttwu_local().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'kernel/sched/core.c')
| -rw-r--r-- | kernel/sched/core.c | 8 |
1 files changed, 3 insertions, 5 deletions
diff --git a/kernel/sched/core.c b/kernel/sched/core.c index dead90d680fd..179a6c928bf1 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -2114,7 +2114,7 @@ static void try_to_wake_up_local(struct task_struct *p, struct rq_flags *rf) delayacct_blkio_end(); atomic_dec(&rq->nr_iowait); } - ttwu_activate(rq, p, ENQUEUE_WAKEUP); + ttwu_activate(rq, p, ENQUEUE_WAKEUP | ENQUEUE_NOCLOCK); } ttwu_do_wakeup(rq, p, 0, rf); @@ -3393,13 +3393,14 @@ static void __sched notrace __schedule(bool preempt) /* Promote REQ to ACT */ rq->clock_update_flags <<= 1; + update_rq_clock(rq); switch_count = &prev->nivcsw; if (!preempt && prev->state) { if (unlikely(signal_pending_state(prev->state, prev))) { prev->state = TASK_RUNNING; } else { - deactivate_task(rq, prev, DEQUEUE_SLEEP); + deactivate_task(rq, prev, DEQUEUE_SLEEP | DEQUEUE_NOCLOCK); prev->on_rq = 0; if (prev->in_iowait) { @@ -3423,9 +3424,6 @@ static void __sched notrace __schedule(bool preempt) switch_count = &prev->nvcsw; } - if (task_on_rq_queued(prev)) - update_rq_clock(rq); - next = pick_next_task(rq, prev, &rf); clear_tsk_need_resched(prev); clear_preempt_need_resched(); |
