From 4a6dae6d382e9edf3ff440b819e554ed706359bc Mon Sep 17 00:00:00 2001
From: Nick Piggin <nickpiggin@yahoo.com.au>
Date: Sun, 13 Nov 2005 16:07:24 -0800
Subject: [PATCH] atomic: cmpxchg

Introduce an atomic_cmpxchg operation.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: "Paul E. McKenney" <paulmck@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
 include/asm-powerpc/atomic.h | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'include/asm-powerpc/atomic.h')

diff --git a/include/asm-powerpc/atomic.h b/include/asm-powerpc/atomic.h
index 9c0b372a46e1..37205faa9d7c 100644
--- a/include/asm-powerpc/atomic.h
+++ b/include/asm-powerpc/atomic.h
@@ -164,6 +164,8 @@ static __inline__ int atomic_dec_return(atomic_t *v)
 	return t;
 }
 
+#define atomic_cmpxchg(v, o, n) ((int)cmpxchg(&((v)->counter), (o), (n)))
+
 #define atomic_sub_and_test(a, v)	(atomic_sub_return((a), (v)) == 0)
 #define atomic_dec_and_test(v)		(atomic_dec_return((v)) == 0)
 
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