From ccdea2f88b5689f0fd29c3804be43a3acf0311e3 Mon Sep 17 00:00:00 2001
From: Ralf Baechle <ralf@linux-mips.org>
Date: Wed, 6 Dec 2006 20:40:26 -0800
Subject: [PATCH] [PATCH] futex: remove unneeded barrier

When disassembling a kernel I found around over 90 sync Instructions from
mb, rmb and wmb calls in the kernel and only few of those make any sense to
me.  So here's the first one - I think the wmb() in kernel/futex.c is not
needed on uniprocessors so should become an smb_wmb().

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
 kernel/futex.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/kernel/futex.c b/kernel/futex.c
index d60b7f7a8cc3..a8302a1620ea 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -552,7 +552,7 @@ static void wake_futex(struct futex_q *q)
 	 * at the end of wake_up_all() does not prevent this store from
 	 * moving.
 	 */
-	wmb();
+	smp_wmb();
 	q->lock_ptr = NULL;
 }
 
-- 
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