diff options
Diffstat (limited to 'include/asm-generic/bitops/lock.h')
-rw-r--r-- | include/asm-generic/bitops/lock.h | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/include/asm-generic/bitops/lock.h b/include/asm-generic/bitops/lock.h index c30266e94806..8ef0ccbf8167 100644 --- a/include/asm-generic/bitops/lock.h +++ b/include/asm-generic/bitops/lock.h | |||
@@ -29,16 +29,16 @@ do { \ | |||
29 | * @nr: the bit to set | 29 | * @nr: the bit to set |
30 | * @addr: the address to start counting from | 30 | * @addr: the address to start counting from |
31 | * | 31 | * |
32 | * This operation is like clear_bit_unlock, however it is not atomic. | 32 | * A weaker form of clear_bit_unlock() as used by __bit_lock_unlock(). If all |
33 | * It does provide release barrier semantics so it can be used to unlock | 33 | * the bits in the word are protected by this lock some archs can use weaker |
34 | * a bit lock, however it would only be used if no other CPU can modify | 34 | * ops to safely unlock. |
35 | * any bits in the memory until the lock is released (a good example is | 35 | * |
36 | * if the bit lock itself protects access to the other bits in the word). | 36 | * See for example x86's implementation. |
37 | */ | 37 | */ |
38 | #define __clear_bit_unlock(nr, addr) \ | 38 | #define __clear_bit_unlock(nr, addr) \ |
39 | do { \ | 39 | do { \ |
40 | smp_mb(); \ | 40 | smp_mb__before_atomic(); \ |
41 | __clear_bit(nr, addr); \ | 41 | clear_bit(nr, addr); \ |
42 | } while (0) | 42 | } while (0) |
43 | 43 | ||
44 | #endif /* _ASM_GENERIC_BITOPS_LOCK_H_ */ | 44 | #endif /* _ASM_GENERIC_BITOPS_LOCK_H_ */ |