diff options
| author | Mike Frysinger <vapier@gentoo.org> | 2009-06-08 18:11:21 -0400 |
|---|---|---|
| committer | Mike Frysinger <vapier@gentoo.org> | 2009-06-13 07:20:14 -0400 |
| commit | e38eb89210ce7171291e4164c24b8d1e6c5385ea (patch) | |
| tree | 3ce36bb9be39634ee781f08d4e66328bcc33ed25 | |
| parent | 8f86001f76609f70bfcce34e7e2a11860e012ace (diff) | |
Blackfin: punt unused/wrong mutex-dec.h
Looks like the mutex-dec.h header file was incorrectly copied into the
Blackfin asm path. Nothing uses it, so punt it.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
| -rw-r--r-- | arch/blackfin/include/asm/mutex-dec.h | 112 |
1 files changed, 0 insertions, 112 deletions
diff --git a/arch/blackfin/include/asm/mutex-dec.h b/arch/blackfin/include/asm/mutex-dec.h deleted file mode 100644 index 0134151656af..000000000000 --- a/arch/blackfin/include/asm/mutex-dec.h +++ /dev/null | |||
| @@ -1,112 +0,0 @@ | |||
| 1 | /* | ||
| 2 | * include/asm-generic/mutex-dec.h | ||
| 3 | * | ||
| 4 | * Generic implementation of the mutex fastpath, based on atomic | ||
| 5 | * decrement/increment. | ||
| 6 | */ | ||
| 7 | #ifndef _ASM_GENERIC_MUTEX_DEC_H | ||
| 8 | #define _ASM_GENERIC_MUTEX_DEC_H | ||
| 9 | |||
| 10 | /** | ||
| 11 | * __mutex_fastpath_lock - try to take the lock by moving the count | ||
| 12 | * from 1 to a 0 value | ||
| 13 | * @count: pointer of type atomic_t | ||
| 14 | * @fail_fn: function to call if the original value was not 1 | ||
| 15 | * | ||
| 16 | * Change the count from 1 to a value lower than 1, and call <fail_fn> if | ||
| 17 | * it wasn't 1 originally. This function MUST leave the value lower than | ||
| 18 | * 1 even when the "1" assertion wasn't true. | ||
| 19 | */ | ||
| 20 | static inline void | ||
| 21 | __mutex_fastpath_lock(atomic_t *count, fastcall void (*fail_fn)(atomic_t *)) | ||
| 22 | { | ||
| 23 | if (unlikely(atomic_dec_return(count) < 0)) | ||
| 24 | fail_fn(count); | ||
| 25 | else | ||
| 26 | smp_mb(); | ||
| 27 | } | ||
| 28 | |||
| 29 | /** | ||
| 30 | * __mutex_fastpath_lock_retval - try to take the lock by moving the count | ||
| 31 | * from 1 to a 0 value | ||
| 32 | * @count: pointer of type atomic_t | ||
| 33 | * @fail_fn: function to call if the original value was not 1 | ||
| 34 | * | ||
| 35 | * Change the count from 1 to a value lower than 1, and call <fail_fn> if | ||
| 36 | * it wasn't 1 originally. This function returns 0 if the fastpath succeeds, | ||
| 37 | * or anything the slow path function returns. | ||
| 38 | */ | ||
| 39 | static inline int | ||
| 40 | __mutex_fastpath_lock_retval(atomic_t *count, fastcall int (*fail_fn)(atomic_t *)) | ||
| 41 | { | ||
| 42 | if (unlikely(atomic_dec_return(count) < 0)) | ||
| 43 | return fail_fn(count); | ||
| 44 | else { | ||
| 45 | smp_mb(); | ||
| 46 | return 0; | ||
| 47 | } | ||
| 48 | } | ||
| 49 | |||
| 50 | /** | ||
| 51 | * __mutex_fastpath_unlock - try to promote the count from 0 to 1 | ||
| 52 | * @count: pointer of type atomic_t | ||
| 53 | * @fail_fn: function to call if the original value was not 0 | ||
| 54 | * | ||
| 55 | * Try to promote the count from 0 to 1. If it wasn't 0, call <fail_fn>. | ||
| 56 | * In the failure case, this function is allowed to either set the value to | ||
| 57 | * 1, or to set it to a value lower than 1. | ||
| 58 | * | ||
| 59 | * If the implementation sets it to a value of lower than 1, then the | ||
| 60 | * __mutex_slowpath_needs_to_unlock() macro needs to return 1, it needs | ||
| 61 | * to return 0 otherwise. | ||
| 62 | */ | ||
| 63 | static inline void | ||
| 64 | __mutex_fastpath_unlock(atomic_t *count, fastcall void (*fail_fn)(atomic_t *)) | ||
| 65 | { | ||
| 66 | smp_mb(); | ||
| 67 | if (unlikely(atomic_inc_return(count) <= 0)) | ||
| 68 | fail_fn(count); | ||
| 69 | } | ||
| 70 | |||
| 71 | #define __mutex_slowpath_needs_to_unlock() 1 | ||
| 72 | |||
| 73 | /** | ||
| 74 | * __mutex_fastpath_trylock - try to acquire the mutex, without waiting | ||
| 75 | * | ||
| 76 | * @count: pointer of type atomic_t | ||
| 77 | * @fail_fn: fallback function | ||
| 78 | * | ||
| 79 | * Change the count from 1 to a value lower than 1, and return 0 (failure) | ||
| 80 | * if it wasn't 1 originally, or return 1 (success) otherwise. This function | ||
| 81 | * MUST leave the value lower than 1 even when the "1" assertion wasn't true. | ||
| 82 | * Additionally, if the value was < 0 originally, this function must not leave | ||
| 83 | * it to 0 on failure. | ||
| 84 | * | ||
| 85 | * If the architecture has no effective trylock variant, it should call the | ||
| 86 | * <fail_fn> spinlock-based trylock variant unconditionally. | ||
| 87 | */ | ||
| 88 | static inline int | ||
| 89 | __mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *)) | ||
| 90 | { | ||
| 91 | /* | ||
| 92 | * We have two variants here. The cmpxchg based one is the best one | ||
| 93 | * because it never induce a false contention state. It is included | ||
| 94 | * here because architectures using the inc/dec algorithms over the | ||
| 95 | * xchg ones are much more likely to support cmpxchg natively. | ||
| 96 | * | ||
| 97 | * If not we fall back to the spinlock based variant - that is | ||
| 98 | * just as efficient (and simpler) as a 'destructive' probing of | ||
| 99 | * the mutex state would be. | ||
| 100 | */ | ||
| 101 | #ifdef __HAVE_ARCH_CMPXCHG | ||
| 102 | if (likely(atomic_cmpxchg(count, 1, 0) == 1)) { | ||
| 103 | smp_mb(); | ||
| 104 | return 1; | ||
| 105 | } | ||
| 106 | return 0; | ||
| 107 | #else | ||
| 108 | return fail_fn(count); | ||
| 109 | #endif | ||
| 110 | } | ||
| 111 | |||
| 112 | #endif | ||
