From 8b680d31440f914ce670db10b5b98a6680a0d9e3 Mon Sep 17 00:00:00 2001
From: Mike Galbraith <mgalbraith@suse.de>
Date: Tue, 22 Nov 2011 15:21:26 +0100
Subject: [PATCH] --- yaml --- r: 277383 b: refs/heads/master c:
 916671c08b7808aebec87cc56c85788e665b3c6b h: refs/heads/master i:   277381:
 f30bdbd035507c07fdd9b88e1f0a9173814ed392   277379:
 840f86e21c5cbe13d8b71f0151295ff0e9ab3ef7   277375:
 b37a1d9e32de8fccb3d021c4ac83f9c53b596259 v: v3

---
 [refs]                    | 2 +-
 trunk/kernel/sched/core.c | 7 +++++++
 trunk/kernel/sched/fair.c | 6 ++++++
 3 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index ccbfe9e63629..03fa78011a5f 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 76854c7e8f3f4172fef091e78d88b3b751463ac6
+refs/heads/master: 916671c08b7808aebec87cc56c85788e665b3c6b
diff --git a/trunk/kernel/sched/core.c b/trunk/kernel/sched/core.c
index ca8fd44145ac..db313c33af29 100644
--- a/trunk/kernel/sched/core.c
+++ b/trunk/kernel/sched/core.c
@@ -4547,6 +4547,13 @@ bool __sched yield_to(struct task_struct *p, bool preempt)
 		 */
 		if (preempt && rq != p_rq)
 			resched_task(p_rq->curr);
+	} else {
+		/*
+		 * We might have set it in task_yield_fair(), but are
+		 * not going to schedule(), so don't want to skip
+		 * the next update.
+		 */
+		rq->skip_clock_update = 0;
 	}
 
 out:
diff --git a/trunk/kernel/sched/fair.c b/trunk/kernel/sched/fair.c
index 8e534a05e3ed..81ccb811afb4 100644
--- a/trunk/kernel/sched/fair.c
+++ b/trunk/kernel/sched/fair.c
@@ -3075,6 +3075,12 @@ static void yield_task_fair(struct rq *rq)
 		 * Update run-time statistics of the 'current'.
 		 */
 		update_curr(cfs_rq);
+		/*
+		 * Tell update_rq_clock() that we've just updated,
+		 * so we don't do microscopic update in schedule()
+		 * and double the fastpath cost.
+		 */
+		 rq->skip_clock_update = 1;
 	}
 
 	set_skip_buddy(se);