From 10554d369ce45176c9e37dafb02c0fb4857bb6ab Mon Sep 17 00:00:00 2001
From: Mike Galbraith <efault@gmx.de>
Date: Fri, 29 Apr 2011 08:36:50 +0200
Subject: [PATCH] --- yaml --- r: 245604 b: refs/heads/master c:
 61eadef6a9bde9ea62fda724a9cb501ce9bc925a h: refs/heads/master v: v3

---
 [refs]                  | 2 +-
 trunk/kernel/sched.c    | 6 +++---
 trunk/kernel/sched_rt.c | 7 +++++++
 3 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/[refs] b/[refs]
index 19a1b6a4a5bf..36c4986c441c 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 3e51e3edfd81bfd9853ad7de91167e4ce33d0fe7
+refs/heads/master: 61eadef6a9bde9ea62fda724a9cb501ce9bc925a
diff --git a/trunk/kernel/sched.c b/trunk/kernel/sched.c
index f9778c0d91e2..b8b9a7dac9b0 100644
--- a/trunk/kernel/sched.c
+++ b/trunk/kernel/sched.c
@@ -466,7 +466,7 @@ struct rq {
 	u64 nohz_stamp;
 	unsigned char nohz_balance_kick;
 #endif
-	unsigned int skip_clock_update;
+	int skip_clock_update;
 
 	/* capture load from *all* tasks on this cpu: */
 	struct load_weight load;
@@ -652,7 +652,7 @@ static void update_rq_clock(struct rq *rq)
 {
 	s64 delta;
 
-	if (rq->skip_clock_update)
+	if (rq->skip_clock_update > 0)
 		return;
 
 	delta = sched_clock_cpu(cpu_of(rq)) - rq->clock;
@@ -4127,7 +4127,7 @@ static inline void schedule_debug(struct task_struct *prev)
 
 static void put_prev_task(struct rq *rq, struct task_struct *prev)
 {
-	if (prev->on_rq)
+	if (prev->on_rq || rq->skip_clock_update < 0)
 		update_rq_clock(rq);
 	prev->sched_class->put_prev_task(rq, prev);
 }
diff --git a/trunk/kernel/sched_rt.c b/trunk/kernel/sched_rt.c
index 19ecb3127379..0943ed7a4038 100644
--- a/trunk/kernel/sched_rt.c
+++ b/trunk/kernel/sched_rt.c
@@ -562,6 +562,13 @@ static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
 			if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
 				rt_rq->rt_throttled = 0;
 				enqueue = 1;
+
+				/*
+				 * Force a clock update if the CPU was idle,
+				 * lest wakeup -> unthrottle time accumulate.
+				 */
+				if (rt_rq->rt_nr_running && rq->curr == rq->idle)
+					rq->skip_clock_update = -1;
 			}
 			if (rt_rq->rt_time || rt_rq->rt_nr_running)
 				idle = 0;