sched: Replace use of entity_key()
authorStephan Baerwolf <stephan.baerwolf@tu-ilmenau.de>
Wed, 20 Jul 2011 12:46:59 +0000 (14:46 +0200)
committerIngo Molnar <mingo@elte.hu>
Thu, 21 Jul 2011 16:01:55 +0000 (18:01 +0200)
commit2bd2d6f2dc952fc44fc52887de36e51896da96b9
tree0b08e0ae13cad776cb216a4b85b1eb8d6eda6611
parentacb5a9ba3bd7cd8b3264f67a3789a9587d3b935b
sched: Replace use of entity_key()

"entity_key()" is only used in "__enqueue_entity()" and
its only function is to subtract a tasks vruntime by
its groups minvruntime.
Before this patch a rbtree enqueue-decision is done by
comparing two tasks in the style:

"if (entity_key(cfs_rq, se) < entity_key(cfs_rq, entry))"

which would be

"if (se->vruntime-cfs_rq->min_vruntime < entry->vruntime-cfs_rq->min_vruntime)"

or (if reducing cfs_rq->min_vruntime out)

"if (se->vruntime < entry->vruntime)"

which is

"if (entity_before(se, entry))"

So we do not need "entity_key()".
If "entity_before()" is inline we will also save one subtraction (only one,
because "entity_key(cfs_rq, se)"  was cached in "key")

Signed-off-by: Stephan Baerwolf <stephan.baerwolf@tu-ilmenau.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/n/tip-ns12mnd2h5w8rb9agd8hnsfk@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kernel/sched_fair.c