Commit 725e7580 authored Feb 01, 2011 by Rik van Riel Committed by Ingo Molnar Feb 03, 2011

sched: Check the right ->nr_running in yield_task_fair()



With CONFIG_FAIR_GROUP_SCHED, each task_group has its own cfs_rq.
Yielding to a task from another cfs_rq may be worthwhile, since
a process calling yield typically cannot use the CPU right now.

Therefor, we want to check the per-cpu nr_running, not the
cgroup local one.

Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20110201094715.798c4f86@annuminas.surriel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

parent 6ea72f12

kernel/sched_fair.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1331,7 +1331,7 @@ static void yield_task_fair(struct rq *rq)
		/*
		* Are we the only task in the tree?
		*/
		if (unlikely(cfs_rq->nr_running == 1))
		if (unlikely(rq->nr_running == 1))
		return;

		clear_buddies(cfs_rq, se);