From 71c53d6bf033ad63183c95b61893b89374d29dac Mon Sep 17 00:00:00 2001
From: Peter Zijlstra <peterz@infradead.org>
Date: Thu, 26 Feb 2009 21:40:16 +0100
Subject: [PATCH] --- yaml --- r: 135695 b: refs/heads/master c:
 8325d9c09dedf45476f4d6261d1b6a72e4a7453f h: refs/heads/master i:   135693:
 ac24934c4f5d2fa8a9e71a359c2b7d836fb759b5   135691:
 2447280ab3a72f6d7d544241da22e6274d72a2c8   135687:
 fdebd6900fe79192f55c49d504af72a7ccacc2d5   135679:
 d5790cf00576d96afc26454e44d3ae38f8eaf048 v: v3

---
 [refs]                     |  2 +-
 trunk/kernel/sched_clock.c | 31 ++++++++++++++++++++-----------
 2 files changed, 21 insertions(+), 12 deletions(-)

diff --git a/[refs] b/[refs]
index 42c2909c341c..955bb533aca7 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 83ce400928680a6c8123d492684b27857f5a2d95
+refs/heads/master: 8325d9c09dedf45476f4d6261d1b6a72e4a7453f
diff --git a/trunk/kernel/sched_clock.c b/trunk/kernel/sched_clock.c
index a755d023805a..390f33234bd0 100644
--- a/trunk/kernel/sched_clock.c
+++ b/trunk/kernel/sched_clock.c
@@ -44,9 +44,6 @@ static __read_mostly int sched_clock_running;
 
 #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
 __read_mostly int sched_clock_stable;
-#else
-static const int sched_clock_stable = 1;
-#endif
 
 struct sched_clock_data {
 	/*
@@ -115,14 +112,9 @@ static u64 __update_sched_clock(struct sched_clock_data *scd, u64 now)
 	s64 delta = now - scd->tick_raw;
 	u64 clock, min_clock, max_clock;
 
-	WARN_ON_ONCE(!irqs_disabled());
-
 	if (unlikely(delta < 0))
 		delta = 0;
 
-	if (unlikely(!sched_clock_running))
-		return 0ull;
-
 	/*
 	 * scd->clock = clamp(scd->tick_gtod + delta,
 	 *		      max(scd->tick_gtod, scd->clock),
@@ -201,18 +193,20 @@ u64 sched_clock_cpu(int cpu)
 	return clock;
 }
 
-#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
-
 void sched_clock_tick(void)
 {
-	struct sched_clock_data *scd = this_scd();
+	struct sched_clock_data *scd;
 	u64 now, now_gtod;
 
+	if (sched_clock_stable)
+		return;
+
 	if (unlikely(!sched_clock_running))
 		return;
 
 	WARN_ON_ONCE(!irqs_disabled());
 
+	scd = this_scd();
 	now_gtod = ktime_to_ns(ktime_get());
 	now = sched_clock();
 
@@ -245,6 +239,21 @@ void sched_clock_idle_wakeup_event(u64 delta_ns)
 }
 EXPORT_SYMBOL_GPL(sched_clock_idle_wakeup_event);
 
+#else /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */
+
+void sched_clock_init(void)
+{
+	sched_clock_running = 1;
+}
+
+u64 sched_clock_cpu(int cpu)
+{
+	if (unlikely(!sched_clock_running))
+		return 0;
+
+	return sched_clock();
+}
+
 #endif /* CONFIG_HAVE_UNSTABLE_SCHED_CLOCK */
 
 unsigned long long cpu_clock(int cpu)