From 091b76d6aa788d8294caa2895cea1013f3eff7da Mon Sep 17 00:00:00 2001
From: Greg Ungerer <gerg@snapgear.com>
Date: Thu, 14 Feb 2008 19:31:25 -0800
Subject: [PATCH] m68knommu: avoid unneccessary use of xchg() in set_mb()

Avoid unneccessary use of xchg() in set_mb().

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
 include/asm-m68knommu/system.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/asm-m68knommu/system.h b/include/asm-m68knommu/system.h
index 039ab3f817..64c64432bb 100644
--- a/include/asm-m68knommu/system.h
+++ b/include/asm-m68knommu/system.h
@@ -104,7 +104,7 @@ asmlinkage void resume(void);
 #define mb()   asm volatile (""   : : :"memory")
 #define rmb()  asm volatile (""   : : :"memory")
 #define wmb()  asm volatile (""   : : :"memory")
-#define set_mb(var, value) do { xchg(&var, value); } while (0)
+#define set_mb(var, value)	({ (var) = (value); wmb(); })
 
 #ifdef CONFIG_SMP
 #define smp_mb()	mb()
-- 
2.39.5