From: Mark Hambleton mahamble@broadcom.com
Make sure the value we are going to return is referenced in order to avoid warnings from newer GCCs such as:
arch/arm64/include/asm/cmpxchg.h:162:3: warning: value computed is not used [-Wunused-value] ((__typeof__(*(ptr)))__cmpxchg_mb((ptr), \ ^ net/netfilter/nf_conntrack_core.c:674:2: note: in expansion of macro ‘cmpxchg’ cmpxchg(&nf_conntrack_hash_rnd, 0, rand);
[Modified to use the current underlying implementation as current mainline for both cmpxchg() and cmpxchg_local() does -- broonie]
Signed-off-by: Mark Hambleton mahamble@broadcom.com Signed-off-by: Mark Brown broonie@linaro.org --- arch/arm64/include/asm/cmpxchg.h | 28 +++++++++++++++++----------- 1 file changed, 17 insertions(+), 11 deletions(-)
diff --git a/arch/arm64/include/asm/cmpxchg.h b/arch/arm64/include/asm/cmpxchg.h index 3914c0dcd09c..3f75fdb59447 100644 --- a/arch/arm64/include/asm/cmpxchg.h +++ b/arch/arm64/include/asm/cmpxchg.h @@ -158,17 +158,23 @@ static inline unsigned long __cmpxchg_mb(volatile void *ptr, unsigned long old, return ret; }
-#define cmpxchg(ptr,o,n) \ - ((__typeof__(*(ptr)))__cmpxchg_mb((ptr), \ - (unsigned long)(o), \ - (unsigned long)(n), \ - sizeof(*(ptr)))) - -#define cmpxchg_local(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; \ +}) + +#define cmpxchg_local(ptr, o, n) \ +({ \ + __typeof__(*(ptr)) __ret; \ + __ret = (__typeof__(*(ptr))) \ + __cmpxchg_local((ptr), (unsigned long)(o), \ + (unsigned long)(n), sizeof(*(ptr))); \ + __ret; \ +})
#define cmpxchg64(ptr,o,n) cmpxchg((ptr),(o),(n)) #define cmpxchg64_local(ptr,o,n) cmpxchg_local((ptr),(o),(n))
On Tue, Dec 03, 2013 at 07:15:27PM +0000, Mark Brown wrote:
From: Mark Hambleton mahamble@broadcom.com
Make sure the value we are going to return is referenced in order to avoid warnings from newer GCCs such as:
Sorry, I was missing a commit --amend here - resent with the correction made.
On Tue, Dec 03, 2013 at 07:15:27PM +0000, Mark Brown wrote:
From: Mark Hambleton mahamble@broadcom.com
Make sure the value we are going to return is referenced in order to avoid warnings from newer GCCs such as:
arch/arm64/include/asm/cmpxchg.h:162:3: warning: value computed is not used [-Wunused-value] ((__typeof__(*(ptr)))__cmpxchg_mb((ptr), \ ^ net/netfilter/nf_conntrack_core.c:674:2: note: in expansion of macro ‘cmpxchg’ cmpxchg(&nf_conntrack_hash_rnd, 0, rand);
[Modified to use the current underlying implementation as current mainline for both cmpxchg() and cmpxchg_local() does -- broonie]
Signed-off-by: Mark Hambleton mahamble@broadcom.com Signed-off-by: Mark Brown broonie@linaro.org
arch/arm64/include/asm/cmpxchg.h | 28 +++++++++++++++++----------- 1 file changed, 17 insertions(+), 11 deletions(-)
diff --git a/arch/arm64/include/asm/cmpxchg.h b/arch/arm64/include/asm/cmpxchg.h index 3914c0dcd09c..3f75fdb59447 100644 --- a/arch/arm64/include/asm/cmpxchg.h +++ b/arch/arm64/include/asm/cmpxchg.h @@ -158,17 +158,23 @@ static inline unsigned long __cmpxchg_mb(volatile void *ptr, unsigned long old, return ret; } -#define cmpxchg(ptr,o,n) \
- ((__typeof__(*(ptr)))__cmpxchg_mb((ptr), \
(unsigned long)(o), \(unsigned long)(n), \sizeof(*(ptr))))-#define cmpxchg_local(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; \
+})
+#define cmpxchg_local(ptr, o, n) \ +({ \
- __typeof__(*(ptr)) __ret; \
- __ret = (__typeof__(*(ptr))) \
- __cmpxchg_local((ptr), (unsigned long)(o), \
(unsigned long)(n), sizeof(*(ptr))); \- __ret; \
+})
NAK.
This removes barrier semantics from cmpxchg and makes cmpxchg_local refer to something which isn't defined anywhere, so the kernel doesn't even build.
Will
On Wed, Dec 04, 2013 at 07:29:38PM +0000, Will Deacon wrote:
This removes barrier semantics from cmpxchg and makes cmpxchg_local refer to something which isn't defined anywhere, so the kernel doesn't even build.
Yes, see the followup I sent to this last night (and the fixed version) - I forgot to do the git add before I did the commit --amend to fix them.
linaro-kernel@lists.linaro.org
-
Mark Brown -
Will Deacon