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-rw-r--r--include/asm-generic/mutex-xchg.h33
1 files changed, 17 insertions, 16 deletions
diff --git a/include/asm-generic/mutex-xchg.h b/include/asm-generic/mutex-xchg.h
index 1d24f47e6c48..32a2100c1aeb 100644
--- a/include/asm-generic/mutex-xchg.h
+++ b/include/asm-generic/mutex-xchg.h
@@ -3,7 +3,7 @@
3 * 3 *
4 * Generic implementation of the mutex fastpath, based on xchg(). 4 * Generic implementation of the mutex fastpath, based on xchg().
5 * 5 *
6 * NOTE: An xchg based implementation is less optimal than an atomic 6 * NOTE: An xchg based implementation might be less optimal than an atomic
7 * decrement/increment based implementation. If your architecture 7 * decrement/increment based implementation. If your architecture
8 * has a reasonable atomic dec/inc then you should probably use 8 * has a reasonable atomic dec/inc then you should probably use
9 * asm-generic/mutex-dec.h instead, or you could open-code an 9 * asm-generic/mutex-dec.h instead, or you could open-code an
@@ -22,14 +22,14 @@
22 * wasn't 1 originally. This function MUST leave the value lower than 1 22 * wasn't 1 originally. This function MUST leave the value lower than 1
23 * even when the "1" assertion wasn't true. 23 * even when the "1" assertion wasn't true.
24 */ 24 */
25#define __mutex_fastpath_lock(count, fail_fn) \ 25static inline void
26do { \ 26__mutex_fastpath_lock(atomic_t *count, fastcall void (*fail_fn)(atomic_t *))
27 if (unlikely(atomic_xchg(count, 0) != 1)) \ 27{
28 fail_fn(count); \ 28 if (unlikely(atomic_xchg(count, 0) != 1))
29 else \ 29 fail_fn(count);
30 smp_mb(); \ 30 else
31} while (0) 31 smp_mb();
32 32}
33 33
34/** 34/**
35 * __mutex_fastpath_lock_retval - try to take the lock by moving the count 35 * __mutex_fastpath_lock_retval - try to take the lock by moving the count
@@ -42,7 +42,7 @@ do { \
42 * or anything the slow path function returns 42 * or anything the slow path function returns
43 */ 43 */
44static inline int 44static inline int
45__mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *)) 45__mutex_fastpath_lock_retval(atomic_t *count, fastcall int (*fail_fn)(atomic_t *))
46{ 46{
47 if (unlikely(atomic_xchg(count, 0) != 1)) 47 if (unlikely(atomic_xchg(count, 0) != 1))
48 return fail_fn(count); 48 return fail_fn(count);
@@ -64,12 +64,13 @@ __mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *))
64 * __mutex_slowpath_needs_to_unlock() macro needs to return 1, it needs 64 * __mutex_slowpath_needs_to_unlock() macro needs to return 1, it needs
65 * to return 0 otherwise. 65 * to return 0 otherwise.
66 */ 66 */
67#define __mutex_fastpath_unlock(count, fail_fn) \ 67static inline void
68do { \ 68__mutex_fastpath_unlock(atomic_t *count, fastcall void (*fail_fn)(atomic_t *))
69 smp_mb(); \ 69{
70 if (unlikely(atomic_xchg(count, 1) != 0)) \ 70 smp_mb();
71 fail_fn(count); \ 71 if (unlikely(atomic_xchg(count, 1) != 0))
72} while (0) 72 fail_fn(count);
73}
73 74
74#define __mutex_slowpath_needs_to_unlock() 0 75#define __mutex_slowpath_needs_to_unlock() 0
75 76