X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=include%2Fasm-ia64%2Fmutex.h;fp=include%2Fasm-ia64%2Fmutex.h;h=458c1f7fbc1808d48982aa0c5fe89bfe3df2098c;hb=64ba3f394c830ec48a1c31b53dcae312c56f1604;hp=bed73a643a56e3c0169a4fd43b705fcba491f5c8;hpb=be1e6109ac94a859551f8e1774eb9a8469fe055c;p=linux-2.6.git diff --git a/include/asm-ia64/mutex.h b/include/asm-ia64/mutex.h index bed73a643..458c1f7fb 100644 --- a/include/asm-ia64/mutex.h +++ b/include/asm-ia64/mutex.h @@ -1,92 +1,9 @@ /* - * ia64 implementation of the mutex fastpath. + * Pull in the generic implementation for the mutex fastpath. * - * Copyright (C) 2006 Ken Chen - * - */ - -#ifndef _ASM_MUTEX_H -#define _ASM_MUTEX_H - -/** - * __mutex_fastpath_lock - 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 if - * it wasn't 1 originally. This function MUST leave the value lower than - * 1 even when the "1" assertion wasn't true. - */ -static inline void -__mutex_fastpath_lock(atomic_t *count, void (*fail_fn)(atomic_t *)) -{ - if (unlikely(ia64_fetchadd4_acq(count, -1) != 1)) - fail_fn(count); -} - -/** - * __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 if - * it wasn't 1 originally. This function returns 0 if the fastpath succeeds, - * or anything the slow path function returns. - */ -static inline int -__mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *)) -{ - if (unlikely(ia64_fetchadd4_acq(count, -1) != 1)) - return fail_fn(count); - return 0; -} - -/** - * __mutex_fastpath_unlock - try to promote the count from 0 to 1 - * @count: pointer of type atomic_t - * @fail_fn: function to call if the original value was not 0 - * - * Try to promote the count from 0 to 1. If it wasn't 0, call . - * In the failure case, this function is allowed to either set the value to - * 1, or to set it to a value lower than 1. - * - * If the implementation sets it to a value of lower than 1, then the - * __mutex_slowpath_needs_to_unlock() macro needs to return 1, it needs - * to return 0 otherwise. - */ -static inline void -__mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *)) -{ - int ret = ia64_fetchadd4_rel(count, 1); - if (unlikely(ret < 0)) - fail_fn(count); -} - -#define __mutex_slowpath_needs_to_unlock() 1 - -/** - * __mutex_fastpath_trylock - try to acquire the mutex, without waiting - * - * @count: pointer of type atomic_t - * @fail_fn: fallback function - * - * Change the count from 1 to a value lower than 1, and return 0 (failure) - * if it wasn't 1 originally, or return 1 (success) otherwise. This function - * MUST leave the value lower than 1 even when the "1" assertion wasn't true. - * Additionally, if the value was < 0 originally, this function must not leave - * it to 0 on failure. - * - * If the architecture has no effective trylock variant, it should call the - * spinlock-based trylock variant unconditionally. + * TODO: implement optimized primitives instead, or leave the generic + * implementation in place, or pick the atomic_xchg() based generic + * implementation. (see asm-generic/mutex-xchg.h for details) */ -static inline int -__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) -{ - if (cmpxchg_acq(count, 1, 0) == 1) - return 1; - return 0; -} -#endif +#include