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[108.232.152.155]) by mx.google.com with ESMTPSA id 46sm1836508yho.14.2014.09.23.07.30.07 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Tue, 23 Sep 2014 07:30:09 -0700 (PDT) From: Pranith Kumar To: Richard Henderson , Ivan Kokshaysky , Matt Turner , Russell King , Catalin Marinas , Will Deacon , Haavard Skinnemoen , Hans-Christian Egtvedt , Mikael Starvik , Jesper Nilsson , David Howells , Tony Luck , Fenghua Yu , Hirokazu Takata , Geert Uytterhoeven , Ralf Baechle , "James E.J. Bottomley" , Helge Deller , "David S. Miller" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org (maintainer:X86 ARCHITECTURE...), Chris Zankel , Max Filippov , Arnd Bergmann , Peter Zijlstra , "Paul E. McKenney" , Chen Gang , Victor Kamensky , Bjorn Helgaas , "Maciej W. Rozycki" , Sam Ravnborg , linux-alpha@vger.kernel.org (open list:ALPHA PORT), linux-kernel@vger.kernel.org (open list), linux-arm-kernel@lists.infradead.org (moderated list:ARM PORT), linux-cris-kernel@axis.com (open list:CRIS PORT), linux-ia64@vger.kernel.org (open list:IA64 (Itanium) PL...), linux-m32r@ml.linux-m32r.org (moderated list:M32R ARCHITECTURE), linux-m32r-ja@ml.linux-m32r.org (open list:M32R ARCHITECTURE), linux-m68k@lists.linux-m68k.org (open list:M68K ARCHITECTURE), linux-mips@linux-mips.org (open list:MIPS), linux-parisc@vger.kernel.org (open list:PARISC ARCHITECTURE), linux-sh@vger.kernel.org (open list:SUPERH), sparclinux@vger.kernel.org (open list:SPARC + UltraSPAR...), linux-xtensa@linux-xtensa.org (open list:TENSILICA XTENSA...), linux-arch@vger.kernel.org (open list:GENERIC INCLUDE/A...) Subject: [PATCH] atomic_read: Use ACCESS_ONCE() instead of cast to volatile Date: Tue, 23 Sep 2014 10:29:50 -0400 Message-Id: <1411482607-20948-1-git-send-email-bobby.prani@gmail.com> X-Mailer: git-send-email 2.1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20140923_073031_268723_C2088BC0 X-CRM114-Status: GOOD ( 16.16 ) X-Spam-Score: -0.8 (/) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-2.5 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED, FREEMAIL_FROM, RCVD_IN_DNSWL_NONE, RP_MATCHES_RCVD, T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Use the much reader friendly ACCESS_ONCE() instead of the cast to volatile. This is purely a style change. Signed-off-by: Pranith Kumar Acked-by: Jesper Nilsson Acked-by: Hans-Christian Egtvedt Acked-by: Max Filippov --- arch/alpha/include/asm/atomic.h | 4 ++-- arch/arm/include/asm/atomic.h | 2 +- arch/arm64/include/asm/atomic.h | 4 ++-- arch/avr32/include/asm/atomic.h | 2 +- arch/cris/include/asm/atomic.h | 2 +- arch/frv/include/asm/atomic.h | 2 +- arch/ia64/include/asm/atomic.h | 4 ++-- arch/m32r/include/asm/atomic.h | 2 +- arch/m68k/include/asm/atomic.h | 2 +- arch/mips/include/asm/atomic.h | 4 ++-- arch/parisc/include/asm/atomic.h | 4 ++-- arch/sh/include/asm/atomic.h | 2 +- arch/sparc/include/asm/atomic_32.h | 2 +- arch/sparc/include/asm/atomic_64.h | 4 ++-- arch/x86/include/asm/atomic.h | 2 +- arch/x86/include/asm/atomic64_64.h | 2 +- arch/xtensa/include/asm/atomic.h | 2 +- include/asm-generic/atomic.h | 2 +- 18 files changed, 24 insertions(+), 24 deletions(-) diff --git a/arch/alpha/include/asm/atomic.h b/arch/alpha/include/asm/atomic.h index 6fbb53a..8f8eafb 100644 --- a/arch/alpha/include/asm/atomic.h +++ b/arch/alpha/include/asm/atomic.h @@ -17,8 +17,8 @@ #define ATOMIC_INIT(i) { (i) } #define ATOMIC64_INIT(i) { (i) } -#define atomic_read(v) (*(volatile int *)&(v)->counter) -#define atomic64_read(v) (*(volatile long *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) +#define atomic64_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v,i) ((v)->counter = (i)) #define atomic64_set(v,i) ((v)->counter = (i)) diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h index 832f1cd..e22c119 100644 --- a/arch/arm/include/asm/atomic.h +++ b/arch/arm/include/asm/atomic.h @@ -27,7 +27,7 @@ * strex/ldrex monitor on some implementations. The reason we can use it for * atomic_set() is the clrex or dummy strex done on every exception return. */ -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v,i) (((v)->counter) = (i)) #if __LINUX_ARM_ARCH__ >= 6 diff --git a/arch/arm64/include/asm/atomic.h b/arch/arm64/include/asm/atomic.h index b83c325..7047051 100644 --- a/arch/arm64/include/asm/atomic.h +++ b/arch/arm64/include/asm/atomic.h @@ -35,7 +35,7 @@ * strex/ldrex monitor on some implementations. The reason we can use it for * atomic_set() is the clrex or dummy strex done on every exception return. */ -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v,i) (((v)->counter) = (i)) /* @@ -139,7 +139,7 @@ static inline int __atomic_add_unless(atomic_t *v, int a, int u) */ #define ATOMIC64_INIT(i) { (i) } -#define atomic64_read(v) (*(volatile long *)&(v)->counter) +#define atomic64_read(v) ACCESS_ONCE((v)->counter) #define atomic64_set(v,i) (((v)->counter) = (i)) #define ATOMIC64_OP(op, asm_op) \ diff --git a/arch/avr32/include/asm/atomic.h b/arch/avr32/include/asm/atomic.h index 83e980a..2d07ce1 100644 --- a/arch/avr32/include/asm/atomic.h +++ b/arch/avr32/include/asm/atomic.h @@ -19,7 +19,7 @@ #define ATOMIC_INIT(i) { (i) } -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v, i) (((v)->counter) = i) #define ATOMIC_OP_RETURN(op, asm_op, asm_con) \ diff --git a/arch/cris/include/asm/atomic.h b/arch/cris/include/asm/atomic.h index 0033f9d..279766a 100644 --- a/arch/cris/include/asm/atomic.h +++ b/arch/cris/include/asm/atomic.h @@ -17,7 +17,7 @@ #define ATOMIC_INIT(i) { (i) } -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v,i) (((v)->counter) = (i)) /* These should be written in asm but we do it in C for now. */ diff --git a/arch/frv/include/asm/atomic.h b/arch/frv/include/asm/atomic.h index f6c3a16..102190a 100644 --- a/arch/frv/include/asm/atomic.h +++ b/arch/frv/include/asm/atomic.h @@ -31,7 +31,7 @@ */ #define ATOMIC_INIT(i) { (i) } -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v, i) (((v)->counter) = (i)) #ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS diff --git a/arch/ia64/include/asm/atomic.h b/arch/ia64/include/asm/atomic.h index 42919a8..0bf0350 100644 --- a/arch/ia64/include/asm/atomic.h +++ b/arch/ia64/include/asm/atomic.h @@ -21,8 +21,8 @@ #define ATOMIC_INIT(i) { (i) } #define ATOMIC64_INIT(i) { (i) } -#define atomic_read(v) (*(volatile int *)&(v)->counter) -#define atomic64_read(v) (*(volatile long *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) +#define atomic64_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v,i) (((v)->counter) = (i)) #define atomic64_set(v,i) (((v)->counter) = (i)) diff --git a/arch/m32r/include/asm/atomic.h b/arch/m32r/include/asm/atomic.h index 3946b2c..31bb74a 100644 --- a/arch/m32r/include/asm/atomic.h +++ b/arch/m32r/include/asm/atomic.h @@ -28,7 +28,7 @@ * * Atomically reads the value of @v. */ -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) /** * atomic_set - set atomic variable diff --git a/arch/m68k/include/asm/atomic.h b/arch/m68k/include/asm/atomic.h index 663d4ba..e85f047 100644 --- a/arch/m68k/include/asm/atomic.h +++ b/arch/m68k/include/asm/atomic.h @@ -17,7 +17,7 @@ #define ATOMIC_INIT(i) { (i) } -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v, i) (((v)->counter) = i) /* diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h index f3ee721..6dd6bfc 100644 --- a/arch/mips/include/asm/atomic.h +++ b/arch/mips/include/asm/atomic.h @@ -29,7 +29,7 @@ * * Atomically reads the value of @v. */ -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) /* * atomic_set - set atomic variable @@ -306,7 +306,7 @@ static __inline__ int __atomic_add_unless(atomic_t *v, int a, int u) * @v: pointer of type atomic64_t * */ -#define atomic64_read(v) (*(volatile long *)&(v)->counter) +#define atomic64_read(v) ACCESS_ONCE((v)->counter) /* * atomic64_set - set atomic variable diff --git a/arch/parisc/include/asm/atomic.h b/arch/parisc/include/asm/atomic.h index 219750b..226f8ca 100644 --- a/arch/parisc/include/asm/atomic.h +++ b/arch/parisc/include/asm/atomic.h @@ -67,7 +67,7 @@ static __inline__ void atomic_set(atomic_t *v, int i) static __inline__ int atomic_read(const atomic_t *v) { - return (*(volatile int *)&(v)->counter); + return ACCESS_ONCE((v)->counter); } /* exported interface */ @@ -204,7 +204,7 @@ atomic64_set(atomic64_t *v, s64 i) static __inline__ s64 atomic64_read(const atomic64_t *v) { - return (*(volatile long *)&(v)->counter); + return ACCESS_ONCE((v)->counter); } #define atomic64_inc(v) (atomic64_add( 1,(v))) diff --git a/arch/sh/include/asm/atomic.h b/arch/sh/include/asm/atomic.h index f57b8a6..05b9f74 100644 --- a/arch/sh/include/asm/atomic.h +++ b/arch/sh/include/asm/atomic.h @@ -14,7 +14,7 @@ #define ATOMIC_INIT(i) { (i) } -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v,i) ((v)->counter = (i)) #if defined(CONFIG_GUSA_RB) diff --git a/arch/sparc/include/asm/atomic_32.h b/arch/sparc/include/asm/atomic_32.h index 7b024f0..765c177 100644 --- a/arch/sparc/include/asm/atomic_32.h +++ b/arch/sparc/include/asm/atomic_32.h @@ -26,7 +26,7 @@ int atomic_cmpxchg(atomic_t *, int, int); int __atomic_add_unless(atomic_t *, int, int); void atomic_set(atomic_t *, int); -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) #define atomic_add(i, v) ((void)atomic_add_return( (int)(i), (v))) #define atomic_sub(i, v) ((void)atomic_add_return(-(int)(i), (v))) diff --git a/arch/sparc/include/asm/atomic_64.h b/arch/sparc/include/asm/atomic_64.h index 7e4ca1e..4082749 100644 --- a/arch/sparc/include/asm/atomic_64.h +++ b/arch/sparc/include/asm/atomic_64.h @@ -14,8 +14,8 @@ #define ATOMIC_INIT(i) { (i) } #define ATOMIC64_INIT(i) { (i) } -#define atomic_read(v) (*(volatile int *)&(v)->counter) -#define atomic64_read(v) (*(volatile long *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) +#define atomic64_read(v) ACCESS_ONCE((v)->counter) #define atomic_set(v, i) (((v)->counter) = i) #define atomic64_set(v, i) (((v)->counter) = i) diff --git a/arch/x86/include/asm/atomic.h b/arch/x86/include/asm/atomic.h index bf20c81..5e5cd12 100644 --- a/arch/x86/include/asm/atomic.h +++ b/arch/x86/include/asm/atomic.h @@ -24,7 +24,7 @@ */ static inline int atomic_read(const atomic_t *v) { - return (*(volatile int *)&(v)->counter); + return ACCESS_ONCE((v)->counter); } /** diff --git a/arch/x86/include/asm/atomic64_64.h b/arch/x86/include/asm/atomic64_64.h index 46e9052..f8d273e 100644 --- a/arch/x86/include/asm/atomic64_64.h +++ b/arch/x86/include/asm/atomic64_64.h @@ -18,7 +18,7 @@ */ static inline long atomic64_read(const atomic64_t *v) { - return (*(volatile long *)&(v)->counter); + return ACCESS_ONCE((v)->counter); } /** diff --git a/arch/xtensa/include/asm/atomic.h b/arch/xtensa/include/asm/atomic.h index 6266766..00b7d46 100644 --- a/arch/xtensa/include/asm/atomic.h +++ b/arch/xtensa/include/asm/atomic.h @@ -47,7 +47,7 @@ * * Atomically reads the value of @v. */ -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) /** * atomic_set - set atomic variable diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h index 56d4d36..1973ad2 100644 --- a/include/asm-generic/atomic.h +++ b/include/asm-generic/atomic.h @@ -126,7 +126,7 @@ ATOMIC_OP(or, |) * Atomically reads the value of @v. */ #ifndef atomic_read -#define atomic_read(v) (*(volatile int *)&(v)->counter) +#define atomic_read(v) ACCESS_ONCE((v)->counter) #endif /**