From mboxrd@z Thu Jan 1 00:00:00 1970 From: yong.zhang0@gmail.com (Yong Zhang) Date: Thu, 31 May 2012 20:50:12 +0800 Subject: [RFC PATCH] ARM: cmpxchg: define __HAVE_ARCH_CMPXCHG for armv6 and later In-Reply-To: <20120531012450.GA8506@mudshark.cambridge.arm.com> References: <1338364287-11614-1-git-send-email-yong.zhang0@gmail.com> <20120531012450.GA8506@mudshark.cambridge.arm.com> Message-ID: <20120531125012.GA3741@zhy> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, May 31, 2012 at 02:24:50AM +0100, Will Deacon wrote: > Hello, > > On Wed, May 30, 2012 at 08:51:26AM +0100, Yong Zhang wrote: > > diff --git a/arch/arm/include/asm/cmpxchg.h b/arch/arm/include/asm/cmpxchg.h > > index 7eb18c1..a91b44e 100644 > > --- a/arch/arm/include/asm/cmpxchg.h > > +++ b/arch/arm/include/asm/cmpxchg.h > > @@ -127,6 +127,8 @@ static inline unsigned long __xchg(unsigned long x, volatile void *ptr, int size > > > > #else /* min ARCH >= ARMv6 */ > > > > +#define __HAVE_ARCH_CMPXCHG 1 > > + > > extern void __bad_cmpxchg(volatile void *ptr, int size); > > As long as this only requires 4-byte cmpxchg support then I think this is > fine. It looks like that's currently the case, so: Yes and thanks for review. Yong > > Acked-by: Will Deacon > > Will