From: Mike Galbraith <efault@gmx.de>
Date: Fri, 11 Sep 2009 10:01:17 +0000 (+0200)
Subject: sched: Complete buddy switches
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=3cb63d527f76e25dbccce4f577f21aecfa2abac7;p=openwrt%2Fstaging%2Fblogic.git

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>
---

diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index cea5b82242ee..4f6356e70ad6 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 07c8250b404c..6174c1233993 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)