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Diffstat (limited to 'include/asm-sh64/semaphore.h')
-rw-r--r-- | include/asm-sh64/semaphore.h | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/include/asm-sh64/semaphore.h b/include/asm-sh64/semaphore.h new file mode 100644 index 000000000000..fce22bb9a546 --- /dev/null +++ b/include/asm-sh64/semaphore.h | |||
@@ -0,0 +1,123 @@ | |||
1 | #ifndef __ASM_SH64_SEMAPHORE_H | ||
2 | #define __ASM_SH64_SEMAPHORE_H | ||
3 | |||
4 | /* | ||
5 | * This file is subject to the terms and conditions of the GNU General Public | ||
6 | * License. See the file "COPYING" in the main directory of this archive | ||
7 | * for more details. | ||
8 | * | ||
9 | * include/asm-sh64/semaphore.h | ||
10 | * | ||
11 | * Copyright (C) 2000, 2001 Paolo Alberelli | ||
12 | * | ||
13 | * SMP- and interrupt-safe semaphores. | ||
14 | * | ||
15 | * (C) Copyright 1996 Linus Torvalds | ||
16 | * | ||
17 | * SuperH verison by Niibe Yutaka | ||
18 | * (Currently no asm implementation but generic C code...) | ||
19 | * | ||
20 | */ | ||
21 | |||
22 | #include <linux/linkage.h> | ||
23 | #include <linux/spinlock.h> | ||
24 | #include <linux/wait.h> | ||
25 | #include <linux/rwsem.h> | ||
26 | |||
27 | #include <asm/system.h> | ||
28 | #include <asm/atomic.h> | ||
29 | |||
30 | struct semaphore { | ||
31 | atomic_t count; | ||
32 | int sleepers; | ||
33 | wait_queue_head_t wait; | ||
34 | }; | ||
35 | |||
36 | #define __SEMAPHORE_INITIALIZER(name, n) \ | ||
37 | { \ | ||
38 | .count = ATOMIC_INIT(n), \ | ||
39 | .sleepers = 0, \ | ||
40 | .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ | ||
41 | } | ||
42 | |||
43 | #define __MUTEX_INITIALIZER(name) \ | ||
44 | __SEMAPHORE_INITIALIZER(name,1) | ||
45 | |||
46 | #define __DECLARE_SEMAPHORE_GENERIC(name,count) \ | ||
47 | struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) | ||
48 | |||
49 | #define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) | ||
50 | #define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0) | ||
51 | |||
52 | static inline void sema_init (struct semaphore *sem, int val) | ||
53 | { | ||
54 | /* | ||
55 | * *sem = (struct semaphore)__SEMAPHORE_INITIALIZER((*sem),val); | ||
56 | * | ||
57 | * i'd rather use the more flexible initialization above, but sadly | ||
58 | * GCC 2.7.2.3 emits a bogus warning. EGCS doesnt. Oh well. | ||
59 | */ | ||
60 | atomic_set(&sem->count, val); | ||
61 | sem->sleepers = 0; | ||
62 | init_waitqueue_head(&sem->wait); | ||
63 | } | ||
64 | |||
65 | static inline void init_MUTEX (struct semaphore *sem) | ||
66 | { | ||
67 | sema_init(sem, 1); | ||
68 | } | ||
69 | |||
70 | static inline void init_MUTEX_LOCKED (struct semaphore *sem) | ||
71 | { | ||
72 | sema_init(sem, 0); | ||
73 | } | ||
74 | |||
75 | #if 0 | ||
76 | asmlinkage void __down_failed(void /* special register calling convention */); | ||
77 | asmlinkage int __down_failed_interruptible(void /* params in registers */); | ||
78 | asmlinkage int __down_failed_trylock(void /* params in registers */); | ||
79 | asmlinkage void __up_wakeup(void /* special register calling convention */); | ||
80 | #endif | ||
81 | |||
82 | asmlinkage void __down(struct semaphore * sem); | ||
83 | asmlinkage int __down_interruptible(struct semaphore * sem); | ||
84 | asmlinkage int __down_trylock(struct semaphore * sem); | ||
85 | asmlinkage void __up(struct semaphore * sem); | ||
86 | |||
87 | extern spinlock_t semaphore_wake_lock; | ||
88 | |||
89 | static inline void down(struct semaphore * sem) | ||
90 | { | ||
91 | if (atomic_dec_return(&sem->count) < 0) | ||
92 | __down(sem); | ||
93 | } | ||
94 | |||
95 | static inline int down_interruptible(struct semaphore * sem) | ||
96 | { | ||
97 | int ret = 0; | ||
98 | |||
99 | if (atomic_dec_return(&sem->count) < 0) | ||
100 | ret = __down_interruptible(sem); | ||
101 | return ret; | ||
102 | } | ||
103 | |||
104 | static inline int down_trylock(struct semaphore * sem) | ||
105 | { | ||
106 | int ret = 0; | ||
107 | |||
108 | if (atomic_dec_return(&sem->count) < 0) | ||
109 | ret = __down_trylock(sem); | ||
110 | return ret; | ||
111 | } | ||
112 | |||
113 | /* | ||
114 | * Note! This is subtle. We jump to wake people up only if | ||
115 | * the semaphore was negative (== somebody was waiting on it). | ||
116 | */ | ||
117 | static inline void up(struct semaphore * sem) | ||
118 | { | ||
119 | if (atomic_inc_return(&sem->count) <= 0) | ||
120 | __up(sem); | ||
121 | } | ||
122 | |||
123 | #endif /* __ASM_SH64_SEMAPHORE_H */ | ||