From: Heiko Carstens <heiko.carstens@de.ibm.com>
Date: Tue, 29 May 2012 04:54:32 +0000 (+0200)
Subject: s390/cmpxchg: add missing memory barrier to cmpxchg64
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=0c44ca71f59447a5e602c45728829d1cb6a1b4b5;p=linux-beck.git

s390/cmpxchg: add missing memory barrier to cmpxchg64

All cmpxchg functions imply a memory barrier.
cmpxch64 did not have one for 31 bit code, so add it.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---

diff --git a/arch/s390/include/asm/cmpxchg.h b/arch/s390/include/asm/cmpxchg.h
index 81d7908416cf..ebd31481f1d2 100644
--- a/arch/s390/include/asm/cmpxchg.h
+++ b/arch/s390/include/asm/cmpxchg.h
@@ -181,7 +181,7 @@ static inline unsigned long long __cmpxchg64(void *ptr,
 		"	cds	%0,%2,%1"
 		: "+&d" (rp_old), "=Q" (ptr)
 		: "d" (rp_new), "Q" (ptr)
-		: "cc");
+		: "memory", "cc");
 	return rp_old.pair;
 }
 #define cmpxchg64(ptr, o, n)						\