From 4ca5754588088e91813bdc522e65769db241f3bf Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Tue, 15 Sep 2009 12:24:22 -0400
Subject: [PATCH] --- yaml --- r: 162975 b: refs/heads/master c:
 6ca6cca31ddc7cc8b1dc38b12d7593d2667defe8 h: refs/heads/master i:   162973:
 54123e53a8c306f54f3232fdbc914f7b5d2c047c   162971:
 f4e4cb217b106fdda8032bb33629c2263956ae57   162967:
 144f4775ec590d26d70af4e94c2ef01ef2925b27   162959:
 7dd56ee980193efec278324f78d1fd8d273d1e12   162943:
 60cebe31ca483d908af12d45ec221da96ab9a2cd v: v3

---
 [refs]                           |  2 +-
 trunk/kernel/trace/trace_clock.c | 24 ++++++++++++++----------
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/[refs] b/[refs]
index fc4ec41dc385..c1405c029be9 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 555f386c98cc93890f48fdea098936755270304b
+refs/heads/master: 6ca6cca31ddc7cc8b1dc38b12d7593d2667defe8
diff --git a/trunk/kernel/trace/trace_clock.c b/trunk/kernel/trace/trace_clock.c
index b588fd81f7f9..20c5f92e28a8 100644
--- a/trunk/kernel/trace/trace_clock.c
+++ b/trunk/kernel/trace/trace_clock.c
@@ -66,10 +66,14 @@ u64 notrace trace_clock(void)
  * Used by plugins that need globally coherent timestamps.
  */
 
-static u64 prev_trace_clock_time;
-
-static raw_spinlock_t trace_clock_lock ____cacheline_aligned_in_smp =
-	(raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+/* keep prev_time and lock in the same cacheline. */
+static struct {
+	u64 prev_time;
+	raw_spinlock_t lock;
+} trace_clock_struct ____cacheline_aligned_in_smp =
+	{
+		.lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED,
+	};
 
 u64 notrace trace_clock_global(void)
 {
@@ -88,19 +92,19 @@ u64 notrace trace_clock_global(void)
 	if (unlikely(in_nmi()))
 		goto out;
 
-	__raw_spin_lock(&trace_clock_lock);
+	__raw_spin_lock(&trace_clock_struct.lock);
 
 	/*
 	 * TODO: if this happens often then maybe we should reset
-	 * my_scd->clock to prev_trace_clock_time+1, to make sure
+	 * my_scd->clock to prev_time+1, to make sure
 	 * we start ticking with the local clock from now on?
 	 */
-	if ((s64)(now - prev_trace_clock_time) < 0)
-		now = prev_trace_clock_time + 1;
+	if ((s64)(now - trace_clock_struct.prev_time) < 0)
+		now = trace_clock_struct.prev_time + 1;
 
-	prev_trace_clock_time = now;
+	trace_clock_struct.prev_time = now;
 
-	__raw_spin_unlock(&trace_clock_lock);
+	__raw_spin_unlock(&trace_clock_struct.lock);
 
  out:
 	raw_local_irq_restore(flags);