[tip:sched/core] sched: Complete buddy switches

tip-bot for Mike Galbraith
2009-09-16T10:19:58Z

Commit-ID: 3cb63d527f76e25dbccce4f577f21aecfa2abac7
Gitweb: http://git.kernel.org/tip/3cb63d527f76e25dbccce4f577f21aecfa2abac7
Author: Mike Galbraith <efault@gmx.de>
AuthorDate: Fri, 11 Sep 2009 12:01:17 +0200
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Tue, 15 Sep 2009 16:01:02 +0200

sched: Complete buddy switches

Add a NEXT_BUDDY feature flag to aid in debugging.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

---
kernel/sched_fair.c | 3 ++-
kernel/sched_features.h | 1 +
2 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index cea5b82..4f6356e 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -1501,7 +1501,8 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int sync)
*/
if (sched_feat(LAST_BUDDY) && likely(se->on_rq && curr != rq->idle))
set_last_buddy(se);
- set_next_buddy(pse);
+ if (sched_feat(NEXT_BUDDY))
+ set_next_buddy(pse);

/*
* We can come here with TIF_NEED_RESCHED already set from new task
diff --git a/kernel/sched_features.h b/kernel/sched_features.h
index 07c8250..6174c12 100644
--- a/kernel/sched_features.h
+++ b/kernel/sched_features.h
@@ -14,5 +14,6 @@ SCHED_FEAT(LB_WAKEUP_UPDATE, 1)
SCHED_FEAT(ASYM_EFF_LOAD, 1)
SCHED_FEAT(WAKEUP_SYNC, 0)
SCHED_FEAT(WAKEUP_OVERLAP, 0)
+SCHED_FEAT(NEXT_BUDDY, 1)
SCHED_FEAT(LAST_BUDDY, 1)
SCHED_FEAT(OWNER_SPIN, 1)