diff options
| author | Peter Zijlstra <peterz@infradead.org> | 2015-05-12 10:52:27 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@kernel.org> | 2015-05-19 08:31:59 +0200 |
| commit | ab3f02fc237211f0583c1e7ba3bf504747be9b8d (patch) | |
| tree | c859733055aed0ba98fcd4e6d3f160a86deb7d8c /include | |
| parent | 6ce47fd961fa8fb206433789d7754c73cab3b5d0 (diff) | |
locking/arch: Add WRITE_ONCE() to set_mb()
Since we assume set_mb() to result in a single store followed by a
full memory barrier, employ WRITE_ONCE().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/asm-generic/barrier.h | 2 | ||||
| -rw-r--r-- | include/linux/compiler.h | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h index f5c40b0fadc2..3938716b44d7 100644 --- a/include/asm-generic/barrier.h +++ b/include/asm-generic/barrier.h @@ -67,7 +67,7 @@ #endif #ifndef set_mb -#define set_mb(var, value) do { (var) = (value); mb(); } while (0) +#define set_mb(var, value) do { WRITE_ONCE(var, value); mb(); } while (0) #endif #ifndef smp_mb__before_atomic diff --git a/include/linux/compiler.h b/include/linux/compiler.h index a7c0941d10da..03e227ba481c 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -250,7 +250,7 @@ static __always_inline void __write_once_size(volatile void *p, void *res, int s ({ union { typeof(x) __val; char __c[1]; } __u; __read_once_size(&(x), __u.__c, sizeof(x)); __u.__val; }) #define WRITE_ONCE(x, val) \ - ({ typeof(x) __val = (val); __write_once_size(&(x), &__val, sizeof(__val)); __val; }) + ({ union { typeof(x) __val; char __c[1]; } __u = { .__val = (val) }; __write_once_size(&(x), __u.__c, sizeof(x)); __u.__val; }) #endif /* __KERNEL__ */ |