diff options
| author | merge <null@invalid> | 2009-01-22 13:55:32 +0000 |
|---|---|---|
| committer | Andy Green <agreen@octopus.localdomain> | 2009-01-22 13:55:32 +0000 |
| commit | aa6f5ffbdba45aa8e19e5048648fc6c7b25376d3 (patch) | |
| tree | fbb786d0ac6f8a774fd834e9ce951197e60fbffa /arch/blackfin/include/asm/mutex.h | |
| parent | f2d78193eae5dccd3d588d2c8ea0866efc368332 (diff) | |
MERGE-via-pending-tracking-hist-MERGE-via-stable-tracking-MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040-1232632141
pending-tracking-hist top was MERGE-via-stable-tracking-MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040-1232632141 / fdf777a63bcb59e0dfd78bfe2c6242e01f6d4eb9 ... parent commitmessage:
From: merge <null@invalid>
MERGE-via-stable-tracking-hist-MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040
stable-tracking-hist top was MERGE-via-mokopatches-tracking-fix-stray-endmenu-patch-1232632040 / 90463bfd2d5a3c8b52f6e6d71024a00e052b0ced ... parent commitmessage:
From: merge <null@invalid>
MERGE-via-mokopatches-tracking-hist-fix-stray-endmenu-patch
mokopatches-tracking-hist top was fix-stray-endmenu-patch / 3630e0be570de8057e7f8d2fe501ed353cdf34e6 ... parent commitmessage:
From: Andy Green <andy@openmoko.com>
fix-stray-endmenu.patch
Signed-off-by: Andy Green <andy@openmoko.com>
Diffstat (limited to 'arch/blackfin/include/asm/mutex.h')
| -rw-r--r-- | arch/blackfin/include/asm/mutex.h | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/arch/blackfin/include/asm/mutex.h b/arch/blackfin/include/asm/mutex.h index 458c1f7fbc1..5d399256bf0 100644 --- a/arch/blackfin/include/asm/mutex.h +++ b/arch/blackfin/include/asm/mutex.h @@ -6,4 +6,67 @@ * implementation. (see asm-generic/mutex-xchg.h for details) */ +#ifndef _ASM_MUTEX_H +#define _ASM_MUTEX_H + +#ifndef CONFIG_SMP #include <asm-generic/mutex-dec.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 |