diff options
Diffstat (limited to 'include/asm-i386/system.h')
| -rw-r--r-- | include/asm-i386/system.h | 26 |
1 files changed, 22 insertions, 4 deletions
diff --git a/include/asm-i386/system.h b/include/asm-i386/system.h index 563e53b77..d3b01ab8b 100644 --- a/include/asm-i386/system.h +++ b/include/asm-i386/system.h @@ -267,15 +267,33 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, * I expect future Intel CPU's to have a weaker ordering, * but I'd also expect them to finally get their act together * and add some real memory barriers if so. + * + * The Pentium III does add a real memory barrier with the + * sfence instruction, so we use that where appropriate. */ +#ifndef CONFIG_X86_XMM #define mb() __asm__ __volatile__ ("lock; addl $0,0(%%esp)": : :"memory") +#else +#define mb() __asm__ __volatile__ ("sfence": : :"memory") +#endif #define rmb() mb() #define wmb() __asm__ __volatile__ ("": : :"memory") + +#ifdef CONFIG_SMP +#define smp_mb() mb() +#define smp_rmb() rmb() +#define smp_wmb() wmb() +#else +#define smp_mb() barrier() +#define smp_rmb() barrier() +#define smp_wmb() barrier() +#endif + #define set_mb(var, value) do { xchg(&var, value); } while (0) #define set_wmb(var, value) do { var = value; wmb(); } while (0) /* interrupt control.. */ -#define __save_flags(x) __asm__ __volatile__("pushfl ; popl %0":"=g" (x): /* no input */ :"memory") +#define __save_flags(x) __asm__ __volatile__("pushfl ; popl %0":"=g" (x): /* no input */) #define __restore_flags(x) __asm__ __volatile__("pushl %0 ; popfl": /* no output */ :"g" (x):"memory") #define __cli() __asm__ __volatile__("cli": : :"memory") #define __sti() __asm__ __volatile__("sti": : :"memory") @@ -284,9 +302,9 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, /* For spinlocks etc */ #define local_irq_save(x) __asm__ __volatile__("pushfl ; popl %0 ; cli":"=g" (x): /* no input */ :"memory") -#define local_irq_restore(x) __asm__ __volatile__("pushl %0 ; popfl": /* no output */ :"g" (x):"memory") -#define local_irq_disable() __asm__ __volatile__("cli": : :"memory") -#define local_irq_enable() __asm__ __volatile__("sti": : :"memory") +#define local_irq_restore(x) __restore_flags(x) +#define local_irq_disable() __cli() +#define local_irq_enable() __sti() #ifdef CONFIG_SMP |