| Message ID | 1386098127-29070-1-git-send-email-broonie@kernel.org |
|---|---|
| State | New |
| Headers | show |
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.
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))