diff options
-rw-r--r-- | arch/blackfin/include/asm/mutex.h | 77 |
1 files changed, 1 insertions, 76 deletions
diff --git a/arch/blackfin/include/asm/mutex.h b/arch/blackfin/include/asm/mutex.h index f726e3a80ad..ff6101aa2c7 100644 --- a/arch/blackfin/include/asm/mutex.h +++ b/arch/blackfin/include/asm/mutex.h @@ -1,76 +1 @@ -/* - * Pull in the generic implementation for the mutex fastpath. - * - * 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) - * - * Copyright 2006-2009 Analog Devices Inc. - * - * Licensed under the GPL-2 or later. - */ - -#ifndef _ASM_MUTEX_H -#define _ASM_MUTEX_H - -#ifndef CONFIG_SMP -#include <asm-generic/mutex.h> -#else - -static inline void -__mutex_fastpath_lock(atomic_t *count, void (*fail_fn)(atomic_t *)) -{ - if (unlikely(atomic_dec_return(count) < 0)) - fail_fn(count); - else - smp_mb(); -} - -static inline int -__mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *)) -{ - if (unlikely(atomic_dec_return(count) < 0)) - return fail_fn(count); - else { - smp_mb(); - return 0; - } -} - -static inline void -__mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *)) -{ - smp_mb(); - if (unlikely(atomic_inc_return(count) <= 0)) - fail_fn(count); -} - -#define __mutex_slowpath_needs_to_unlock() 1 - -static inline int -__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) -{ - /* - * We have two variants here. The cmpxchg based one is the best one - * because it never induce a false contention state. It is included - * here because architectures using the inc/dec algorithms over the - * xchg ones are much more likely to support cmpxchg natively. - * - * If not we fall back to the spinlock based variant - that is - * just as efficient (and simpler) as a 'destructive' probing of - * the mutex state would be. - */ -#ifdef __HAVE_ARCH_CMPXCHG - if (likely(atomic_cmpxchg(count, 1, 0) == 1)) { - smp_mb(); - return 1; - } - return 0; -#else - return fail_fn(count); -#endif -} - -#endif - -#endif +#include <asm-generic/mutex-dec.h> |