From 62e8a3258bda118f24ff462fe04cfbe75b8189b5 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 18 Sep 2015 11:13:10 +0200 Subject: atomic, arch: Audit atomic_{read,set}() This patch makes sure that atomic_{read,set}() are at least {READ,WRITE}_ONCE(). We already had the 'requirement' that atomic_read() should use ACCESS_ONCE(), and most archs had this, but a few were lacking. All are now converted to use READ_ONCE(). And, by a symmetry and general paranoia argument, upgrade atomic_set() to use WRITE_ONCE(). Signed-off-by: Peter Zijlstra (Intel) Cc: Andrew Morton Cc: Dmitry Vyukov Cc: Linus Torvalds Cc: Paul E. McKenney Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: james.hogan@imgtec.com Cc: linux-kernel@vger.kernel.org Cc: oleg@redhat.com Cc: will.deacon@arm.com Signed-off-by: Ingo Molnar --- arch/arm/include/asm/atomic.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/arm/include') diff --git a/arch/arm/include/asm/atomic.h b/arch/arm/include/asm/atomic.h index fe3ef39..2bf80af 100644 --- a/arch/arm/include/asm/atomic.h +++ b/arch/arm/include/asm/atomic.h @@ -27,8 +27,8 @@ * 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) ACCESS_ONCE((v)->counter) -#define atomic_set(v,i) (((v)->counter) = (i)) +#define atomic_read(v) READ_ONCE((v)->counter) +#define atomic_set(v,i) WRITE_ONCE(((v)->counter), (i)) #if __LINUX_ARM_ARCH__ >= 6 -- cgit v1.1