diff options
Diffstat (limited to 'include/asm-x86_64/system.h')
| -rw-r--r-- | include/asm-x86_64/system.h | 36 |
1 files changed, 36 insertions, 0 deletions
diff --git a/include/asm-x86_64/system.h b/include/asm-x86_64/system.h index 213b7fe5d99..1f1c0bf4a5d 100644 --- a/include/asm-x86_64/system.h +++ b/include/asm-x86_64/system.h @@ -214,9 +214,45 @@ static inline unsigned long __cmpxchg(volatile void *ptr, unsigned long old, return old; } +static inline unsigned long __cmpxchg_local(volatile void *ptr, + unsigned long old, unsigned long new, int size) +{ + unsigned long prev; + switch (size) { + case 1: + __asm__ __volatile__("cmpxchgb %b1,%2" + : "=a"(prev) + : "q"(new), "m"(*__xg(ptr)), "0"(old) + : "memory"); + return prev; + case 2: + __asm__ __volatile__("cmpxchgw %w1,%2" + : "=a"(prev) + : "r"(new), "m"(*__xg(ptr)), "0"(old) + : "memory"); + return prev; + case 4: + __asm__ __volatile__("cmpxchgl %k1,%2" + : "=a"(prev) + : "r"(new), "m"(*__xg(ptr)), "0"(old) + : "memory"); + return prev; + case 8: + __asm__ __volatile__("cmpxchgq %1,%2" + : "=a"(prev) + : "r"(new), "m"(*__xg(ptr)), "0"(old) + : "memory"); + return prev; + } + return old; +} + #define cmpxchg(ptr,o,n)\ ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\ (unsigned long)(n),sizeof(*(ptr)))) +#define cmpxchg_local(ptr,o,n)\ + ((__typeof__(*(ptr)))__cmpxchg((ptr),(unsigned long)(o),\ + (unsigned long)(n),sizeof(*(ptr)))) #ifdef CONFIG_SMP #define smp_mb() mb() |