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>
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 55040f3..4de9905 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1331,7 +1331,7 @@
/*
* 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);