m68knommu: avoid unneccessary use of xchg() in set_mb()

Avoid unneccessary use of xchg() in set_mb().

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Greg Ungerer 2008-02-14 19:31:25 -08:00 committed by Linus Torvalds
parent 903be1c564
commit 091b76d6aa

View File

@ -104,7 +104,7 @@ asmlinkage void resume(void);
#define mb() asm volatile ("" : : :"memory")
#define rmb() asm volatile ("" : : :"memory")
#define wmb() asm volatile ("" : : :"memory")
#define set_mb(var, value) do { xchg(&var, value); } while (0)
#define set_mb(var, value) ({ (var) = (value); wmb(); })
#ifdef CONFIG_SMP
#define smp_mb() mb()