s390/cmpxchg: fix compile warnings specific to s390
The cmpxchg macros and functions are a bit different than on other
architectures. In particular the macros do not store the return
value of a __cmpxchg function call in a variable before returning the
value.
This causes compile warnings that only occur on s390 like this one:
net/ipv4/af_inet.c: In function 'build_ehash_secret':
net/ipv4/af_inet.c:241:2: warning: value computed is not used [-Wunused-value]
To get rid of these warnings use the same construct that we already use
for the xchg macro, which was introduced for the same reason.
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 ebd3148..13c8b2e 100644
--- a/arch/s390/include/asm/cmpxchg.h
+++ b/arch/s390/include/asm/cmpxchg.h
@@ -160,9 +160,14 @@
return old;
}
-#define cmpxchg(ptr, o, n) \
- ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \
- (unsigned long)(n), sizeof(*(ptr))))
+#define cmpxchg(ptr, o, n) \
+({ \
+ __typeof__(*(ptr)) __ret; \
+ __ret = (__typeof__(*(ptr))) \
+ __cmpxchg((ptr), (unsigned long)(o), (unsigned long)(n), \
+ sizeof(*(ptr))); \
+ __ret; \
+})
#ifdef CONFIG_64BIT
#define cmpxchg64(ptr, o, n) \
@@ -184,10 +189,16 @@
: "memory", "cc");
return rp_old.pair;
}
-#define cmpxchg64(ptr, o, n) \
- ((__typeof__(*(ptr)))__cmpxchg64((ptr), \
- (unsigned long long)(o), \
- (unsigned long long)(n)))
+
+#define cmpxchg64(ptr, o, n) \
+({ \
+ __typeof__(*(ptr)) __ret; \
+ __ret = (__typeof__(*(ptr))) \
+ __cmpxchg64((ptr), \
+ (unsigned long long)(o), \
+ (unsigned long long)(n)); \
+ __ret; \
+})
#endif /* CONFIG_64BIT */
#include <asm-generic/cmpxchg-local.h>
@@ -216,8 +227,13 @@
* them available.
*/
#define cmpxchg_local(ptr, o, n) \
- ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \
- (unsigned long)(n), sizeof(*(ptr))))
+({ \
+ __typeof__(*(ptr)) __ret; \
+ __ret = (__typeof__(*(ptr))) \
+ __cmpxchg_local((ptr), (unsigned long)(o), \
+ (unsigned long)(n), sizeof(*(ptr))); \
+ __ret; \
+})
#define cmpxchg64_local(ptr, o, n) cmpxchg64((ptr), (o), (n))