From 2daa357705bfe68788132cf9079930ca948a90af Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 9 Aug 2007 11:16:51 +0200 Subject: [PATCH] sched: optimize activate_task() optimize activate_task() by removing update_rq_clock() from it. (and add update_rq_clock() to all callsites of activate_task() that did not have it before.) Signed-off-by: Ingo Molnar --- kernel/sched.c | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/kernel/sched.c b/kernel/sched.c index 3f5d529499..9ccd91e5b6 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -910,8 +910,6 @@ static int effective_prio(struct task_struct *p) */ static void activate_task(struct rq *rq, struct task_struct *p, int wakeup) { - update_rq_clock(rq); - if (p->state == TASK_UNINTERRUPTIBLE) rq->nr_uninterruptible--; @@ -1510,6 +1508,7 @@ out_set_cpu: out_activate: #endif /* CONFIG_SMP */ + update_rq_clock(rq); activate_task(rq, p, 1); /* * Sync wakeups (i.e. those types of wakeups where the waker @@ -2117,6 +2116,7 @@ static void pull_task(struct rq *src_rq, struct task_struct *p, update_rq_clock(src_rq); deactivate_task(src_rq, p, 0); set_task_cpu(p, this_cpu); + __update_rq_clock(this_rq); activate_task(this_rq, p, 0); /* * Note that idle threads have a prio of MAX_PRIO, for this test @@ -4207,11 +4207,10 @@ recheck: spin_unlock_irqrestore(&p->pi_lock, flags); goto recheck; } + update_rq_clock(rq); on_rq = p->se.on_rq; - if (on_rq) { - update_rq_clock(rq); + if (on_rq) deactivate_task(rq, p, 0); - } oldprio = p->prio; __setscheduler(rq, p, policy, param->sched_priority); if (on_rq) { @@ -4969,6 +4968,7 @@ static int __migrate_task(struct task_struct *p, int src_cpu, int dest_cpu) } set_task_cpu(p, dest_cpu); if (on_rq) { + update_rq_clock(rq_dest); activate_task(rq_dest, p, 0); check_preempt_curr(rq_dest, p); } @@ -6623,14 +6623,13 @@ void normalize_rt_tasks(void) goto out_unlock; #endif + update_rq_clock(rq); on_rq = p->se.on_rq; - if (on_rq) { - update_rq_clock(task_rq(p)); - deactivate_task(task_rq(p), p, 0); - } + if (on_rq) + deactivate_task(rq, p, 0); __setscheduler(rq, p, SCHED_NORMAL, 0); if (on_rq) { - activate_task(task_rq(p), p, 0); + activate_task(rq, p, 0); resched_task(rq->curr); } #ifdef CONFIG_SMP -- 2.39.5