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authorMike Frysinger <vapier@gentoo.org>2011-05-29 12:17:22 -0400
committerMike Frysinger <vapier@gentoo.org>2011-07-23 01:10:43 -0400
commit50f92aa3348a1c810fa809c60227ec80f7a5fd41 (patch)
tree7744d5e7aeaff92b3bf99431178c7c2183e5fee5
parentfb1d9be5967fff0a3c93b06304fd992e3c438b7f (diff)
Blackfin: convert to asm-generic/mutex-dec.h for all systems
The Blackfin mutex.h is merely a copy of an older asm-generic/mutex-dec.h, so punt it and just use the common one directly. Signed-off-by: Mike Frysinger <vapier@gentoo.org>
-rw-r--r--arch/blackfin/include/asm/mutex.h77
1 files changed, 1 insertions, 76 deletions
diff --git a/arch/blackfin/include/asm/mutex.h b/arch/blackfin/include/asm/mutex.h
index f726e3a80ad0..ff6101aa2c71 100644
--- a/arch/blackfin/include/asm/mutex.h
+++ b/arch/blackfin/include/asm/mutex.h
@@ -1,76 +1 @@
1/* #include <asm-generic/mutex-dec.h>
2 * Pull in the generic implementation for the mutex fastpath.
3 *
4 * TODO: implement optimized primitives instead, or leave the generic
5 * implementation in place, or pick the atomic_xchg() based generic
6 * implementation. (see asm-generic/mutex-xchg.h for details)
7 *
8 * Copyright 2006-2009 Analog Devices Inc.
9 *
10 * Licensed under the GPL-2 or later.
11 */
12
13#ifndef _ASM_MUTEX_H
14#define _ASM_MUTEX_H
15
16#ifndef CONFIG_SMP
17#include <asm-generic/mutex.h>
18#else
19
20static inline void
21__mutex_fastpath_lock(atomic_t *count, 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
29static inline int
30__mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *))
31{
32 if (unlikely(atomic_dec_return(count) < 0))
33 return fail_fn(count);
34 else {
35 smp_mb();
36 return 0;
37 }
38}
39
40static inline void
41__mutex_fastpath_unlock(atomic_t *count, void (*fail_fn)(atomic_t *))
42{
43 smp_mb();
44 if (unlikely(atomic_inc_return(count) <= 0))
45 fail_fn(count);
46}
47
48#define __mutex_slowpath_needs_to_unlock() 1
49
50static inline int
51__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *))
52{
53 /*
54 * We have two variants here. The cmpxchg based one is the best one
55 * because it never induce a false contention state. It is included
56 * here because architectures using the inc/dec algorithms over the
57 * xchg ones are much more likely to support cmpxchg natively.
58 *
59 * If not we fall back to the spinlock based variant - that is
60 * just as efficient (and simpler) as a 'destructive' probing of
61 * the mutex state would be.
62 */
63#ifdef __HAVE_ARCH_CMPXCHG
64 if (likely(atomic_cmpxchg(count, 1, 0) == 1)) {
65 smp_mb();
66 return 1;
67 }
68 return 0;
69#else
70 return fail_fn(count);
71#endif
72}
73
74#endif
75
76#endif