diff options
Diffstat (limited to 'sys/arch/i386/include')
| -rw-r--r-- | sys/arch/i386/include/atomic.h | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/sys/arch/i386/include/atomic.h b/sys/arch/i386/include/atomic.h index a06878e87b0..baf3d7bde01 100644 --- a/sys/arch/i386/include/atomic.h +++ b/sys/arch/i386/include/atomic.h @@ -1,4 +1,4 @@ -/* $OpenBSD: atomic.h,v 1.3 2006/04/27 15:37:53 mickey Exp $ */ +/* $OpenBSD: atomic.h,v 1.4 2007/02/06 17:13:33 art Exp $ */ /* $NetBSD: atomic.h,v 1.1.2.2 2000/02/21 18:54:07 sommerfeld Exp $ */ /*- @@ -42,11 +42,24 @@ #ifndef _ATOMIC_H_ #define _ATOMIC_H_ +/* + * Perform atomic operations on memory. Should be atomic with respect + * to interrupts and multiple processors. + * + * void atomic_setbits_int(volatile u_int *a, u_int mask) { *a |= mask; } + * void atomic_clearbits_int(volatile u_int *a, u_int mas) { *a &= ~mask; } + */ #ifndef _LOCORE +#ifdef MULTIPROCESSOR +#define LOCK "lock" +#else +#define LOCK +#endif + static __inline u_int64_t i386_atomic_testset_uq (volatile u_int64_t *ptr, u_int64_t val) { - __asm__ volatile ("\n1:\tlock; cmpxchg8b (%1); jnz 1b" : "+A" (val) : + __asm__ volatile ("\n1:\t" LOCK " cmpxchg8b (%1); jnz 1b" : "+A" (val) : "r" (ptr), "b" ((u_int32_t)val), "c" ((u_int32_t)(val >> 32))); return val; } @@ -65,15 +78,20 @@ i386_atomic_testset_i (volatile int *ptr, unsigned long val) { static __inline void i386_atomic_setbits_l (volatile u_int32_t *ptr, unsigned long bits) { - __asm __volatile("lock ; orl %1,%0" : "=m" (*ptr) : "ir" (bits)); + __asm __volatile(LOCK " orl %1,%0" : "=m" (*ptr) : "ir" (bits)); } static __inline void i386_atomic_clearbits_l (volatile u_int32_t *ptr, unsigned long bits) { bits = ~bits; - __asm __volatile("lock ; and %1,%0" : "=m" (*ptr) : "ir" (bits)); + __asm __volatile(LOCK " andl %1,%0" : "=m" (*ptr) : "ir" (bits)); } +#define atomic_setbits_int i386_atomic_setbits_l +#define atomic_clearbits_int i386_atomic_clearbits_l + +#undef LOCK + #endif #endif |