[PATCH] sched: optimize activate_task for RT task

RT task does not participate in interactiveness priority and thus shouldn't
be bothered with timestamp and p->sleep_type manipulation when task is
being put on run queue.  Bypass all of the them with a single if (rt_task)
test.

Signed-off-by: Ken Chen <kenneth.w.chen@intel.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: "Siddha, Suresh B" <suresh.b.siddha@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Chen, Kenneth W 2006-12-10 02:20:36 -08:00 committed by Linus Torvalds
parent 06066714f6
commit 62ab616d54
1 changed files with 5 additions and 3 deletions

View File

@ -940,6 +940,9 @@ static void activate_task(struct task_struct *p, struct rq *rq, int local)
{
unsigned long long now;
if (rt_task(p))
goto out;
now = sched_clock();
#ifdef CONFIG_SMP
if (!local) {
@ -961,8 +964,7 @@ static void activate_task(struct task_struct *p, struct rq *rq, int local)
(now - p->timestamp) >> 20);
}
if (!rt_task(p))
p->prio = recalc_task_prio(p, now);
p->prio = recalc_task_prio(p, now);
/*
* This checks to make sure it's not an uninterruptible task
@ -987,7 +989,7 @@ static void activate_task(struct task_struct *p, struct rq *rq, int local)
}
}
p->timestamp = now;
out:
__activate_task(p, rq);
}