diff options
Diffstat (limited to 'arch/x86/include/asm/mutex_64.h')
| -rw-r--r-- | arch/x86/include/asm/mutex_64.h | 41 |
1 files changed, 34 insertions, 7 deletions
diff --git a/arch/x86/include/asm/mutex_64.h b/arch/x86/include/asm/mutex_64.h index 68a87b0f8e2..07537a44216 100644 --- a/arch/x86/include/asm/mutex_64.h +++ b/arch/x86/include/asm/mutex_64.h @@ -16,6 +16,20 @@ * * Atomically decrements @v and calls <fail_fn> if the result is negative. */ +#ifdef CC_HAVE_ASM_GOTO +static inline void __mutex_fastpath_lock(atomic_t *v, + void (*fail_fn)(atomic_t *)) +{ + asm_volatile_goto(LOCK_PREFIX " decl %0\n" + " jns %l[exit]\n" + : : "m" (v->counter) + : "memory", "cc" + : exit); + fail_fn(v); +exit: + return; +} +#else #define __mutex_fastpath_lock(v, fail_fn) \ do { \ unsigned long dummy; \ @@ -32,22 +46,20 @@ do { \ : "rax", "rsi", "rdx", "rcx", \ "r8", "r9", "r10", "r11", "memory"); \ } while (0) +#endif /** * __mutex_fastpath_lock_retval - try to take the lock by moving the count * from 1 to a 0 value * @count: pointer of type atomic_t - * @fail_fn: function to call if the original value was not 1 * - * Change the count from 1 to a value lower than 1, and call <fail_fn> if - * it wasn't 1 originally. This function returns 0 if the fastpath succeeds, - * or anything the slow path function returns + * Change the count from 1 to a value lower than 1. This function returns 0 + * if the fastpath succeeds, or -1 otherwise. */ -static inline int __mutex_fastpath_lock_retval(atomic_t *count, - int (*fail_fn)(atomic_t *)) +static inline int __mutex_fastpath_lock_retval(atomic_t *count) { if (unlikely(atomic_dec_return(count) < 0)) - return fail_fn(count); + return -1; else return 0; } @@ -59,6 +71,20 @@ static inline int __mutex_fastpath_lock_retval(atomic_t *count, * * Atomically increments @v and calls <fail_fn> if the result is nonpositive. */ +#ifdef CC_HAVE_ASM_GOTO +static inline void __mutex_fastpath_unlock(atomic_t *v, + void (*fail_fn)(atomic_t *)) +{ + asm_volatile_goto(LOCK_PREFIX " incl %0\n" + " jg %l[exit]\n" + : : "m" (v->counter) + : "memory", "cc" + : exit); + fail_fn(v); +exit: + return; +} +#else #define __mutex_fastpath_unlock(v, fail_fn) \ do { \ unsigned long dummy; \ @@ -75,6 +101,7 @@ do { \ : "rax", "rsi", "rdx", "rcx", \ "r8", "r9", "r10", "r11", "memory"); \ } while (0) +#endif #define __mutex_slowpath_needs_to_unlock() 1 |