From ad46276952f1af34cd91d46d49ba13d347d56367 Mon Sep 17 00:00:00 2001 From: Jiri Olsa Date: Wed, 8 Jul 2009 12:10:31 +0000 Subject: memory barrier: adding smp_mb__after_lock Adding smp_mb__after_lock define to be used as a smp_mb call after a lock. Making it nop for x86, since {read|write|spin}_lock() on x86 are full memory barriers. Signed-off-by: Jiri Olsa Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- include/linux/spinlock.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/linux/spinlock.h') diff --git a/include/linux/spinlock.h b/include/linux/spinlock.h index 252b245cfcf4..4be57ab03478 100644 --- a/include/linux/spinlock.h +++ b/include/linux/spinlock.h @@ -132,6 +132,11 @@ do { \ #endif /*__raw_spin_is_contended*/ #endif +/* The lock does not imply full memory barrier. */ +#ifndef ARCH_HAS_SMP_MB_AFTER_LOCK +static inline void smp_mb__after_lock(void) { smp_mb(); } +#endif + /** * spin_unlock_wait - wait until the spinlock gets unlocked * @lock: the spinlock in question. -- cgit v1.2.3