diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-m68k/semaphore.h |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'include/asm-m68k/semaphore.h')
-rw-r--r-- | include/asm-m68k/semaphore.h | 167 |
1 files changed, 167 insertions, 0 deletions
diff --git a/include/asm-m68k/semaphore.h b/include/asm-m68k/semaphore.h new file mode 100644 index 000000000000..ab94cf3ed447 --- /dev/null +++ b/include/asm-m68k/semaphore.h | |||
@@ -0,0 +1,167 @@ | |||
1 | #ifndef _M68K_SEMAPHORE_H | ||
2 | #define _M68K_SEMAPHORE_H | ||
3 | |||
4 | #define RW_LOCK_BIAS 0x01000000 | ||
5 | |||
6 | #ifndef __ASSEMBLY__ | ||
7 | |||
8 | #include <linux/linkage.h> | ||
9 | #include <linux/wait.h> | ||
10 | #include <linux/spinlock.h> | ||
11 | #include <linux/rwsem.h> | ||
12 | #include <linux/stringify.h> | ||
13 | |||
14 | #include <asm/system.h> | ||
15 | #include <asm/atomic.h> | ||
16 | |||
17 | /* | ||
18 | * Interrupt-safe semaphores.. | ||
19 | * | ||
20 | * (C) Copyright 1996 Linus Torvalds | ||
21 | * | ||
22 | * m68k version by Andreas Schwab | ||
23 | */ | ||
24 | |||
25 | |||
26 | struct semaphore { | ||
27 | atomic_t count; | ||
28 | atomic_t waking; | ||
29 | wait_queue_head_t wait; | ||
30 | }; | ||
31 | |||
32 | #define __SEMAPHORE_INITIALIZER(name, n) \ | ||
33 | { \ | ||
34 | .count = ATOMIC_INIT(n), \ | ||
35 | .waking = ATOMIC_INIT(0), \ | ||
36 | .wait = __WAIT_QUEUE_HEAD_INITIALIZER((name).wait) \ | ||
37 | } | ||
38 | |||
39 | #define __MUTEX_INITIALIZER(name) \ | ||
40 | __SEMAPHORE_INITIALIZER(name,1) | ||
41 | |||
42 | #define __DECLARE_SEMAPHORE_GENERIC(name,count) \ | ||
43 | struct semaphore name = __SEMAPHORE_INITIALIZER(name,count) | ||
44 | |||
45 | #define DECLARE_MUTEX(name) __DECLARE_SEMAPHORE_GENERIC(name,1) | ||
46 | #define DECLARE_MUTEX_LOCKED(name) __DECLARE_SEMAPHORE_GENERIC(name,0) | ||
47 | |||
48 | static inline void sema_init(struct semaphore *sem, int val) | ||
49 | { | ||
50 | *sem = (struct semaphore)__SEMAPHORE_INITIALIZER(*sem, val); | ||
51 | } | ||
52 | |||
53 | static inline void init_MUTEX (struct semaphore *sem) | ||
54 | { | ||
55 | sema_init(sem, 1); | ||
56 | } | ||
57 | |||
58 | static inline void init_MUTEX_LOCKED (struct semaphore *sem) | ||
59 | { | ||
60 | sema_init(sem, 0); | ||
61 | } | ||
62 | |||
63 | asmlinkage void __down_failed(void /* special register calling convention */); | ||
64 | asmlinkage int __down_failed_interruptible(void /* params in registers */); | ||
65 | asmlinkage int __down_failed_trylock(void /* params in registers */); | ||
66 | asmlinkage void __up_wakeup(void /* special register calling convention */); | ||
67 | |||
68 | asmlinkage void __down(struct semaphore * sem); | ||
69 | asmlinkage int __down_interruptible(struct semaphore * sem); | ||
70 | asmlinkage int __down_trylock(struct semaphore * sem); | ||
71 | asmlinkage void __up(struct semaphore * sem); | ||
72 | |||
73 | /* | ||
74 | * This is ugly, but we want the default case to fall through. | ||
75 | * "down_failed" is a special asm handler that calls the C | ||
76 | * routine that actually waits. See arch/m68k/lib/semaphore.S | ||
77 | */ | ||
78 | static inline void down(struct semaphore *sem) | ||
79 | { | ||
80 | register struct semaphore *sem1 __asm__ ("%a1") = sem; | ||
81 | |||
82 | might_sleep(); | ||
83 | __asm__ __volatile__( | ||
84 | "| atomic down operation\n\t" | ||
85 | "subql #1,%0@\n\t" | ||
86 | "jmi 2f\n\t" | ||
87 | "1:\n" | ||
88 | LOCK_SECTION_START(".even\n\t") | ||
89 | "2:\tpea 1b\n\t" | ||
90 | "jbra __down_failed\n" | ||
91 | LOCK_SECTION_END | ||
92 | : /* no outputs */ | ||
93 | : "a" (sem1) | ||
94 | : "memory"); | ||
95 | } | ||
96 | |||
97 | static inline int down_interruptible(struct semaphore *sem) | ||
98 | { | ||
99 | register struct semaphore *sem1 __asm__ ("%a1") = sem; | ||
100 | register int result __asm__ ("%d0"); | ||
101 | |||
102 | might_sleep(); | ||
103 | __asm__ __volatile__( | ||
104 | "| atomic interruptible down operation\n\t" | ||
105 | "subql #1,%1@\n\t" | ||
106 | "jmi 2f\n\t" | ||
107 | "clrl %0\n" | ||
108 | "1:\n" | ||
109 | LOCK_SECTION_START(".even\n\t") | ||
110 | "2:\tpea 1b\n\t" | ||
111 | "jbra __down_failed_interruptible\n" | ||
112 | LOCK_SECTION_END | ||
113 | : "=d" (result) | ||
114 | : "a" (sem1) | ||
115 | : "memory"); | ||
116 | return result; | ||
117 | } | ||
118 | |||
119 | static inline int down_trylock(struct semaphore *sem) | ||
120 | { | ||
121 | register struct semaphore *sem1 __asm__ ("%a1") = sem; | ||
122 | register int result __asm__ ("%d0"); | ||
123 | |||
124 | __asm__ __volatile__( | ||
125 | "| atomic down trylock operation\n\t" | ||
126 | "subql #1,%1@\n\t" | ||
127 | "jmi 2f\n\t" | ||
128 | "clrl %0\n" | ||
129 | "1:\n" | ||
130 | LOCK_SECTION_START(".even\n\t") | ||
131 | "2:\tpea 1b\n\t" | ||
132 | "jbra __down_failed_trylock\n" | ||
133 | LOCK_SECTION_END | ||
134 | : "=d" (result) | ||
135 | : "a" (sem1) | ||
136 | : "memory"); | ||
137 | return result; | ||
138 | } | ||
139 | |||
140 | /* | ||
141 | * Note! This is subtle. We jump to wake people up only if | ||
142 | * the semaphore was negative (== somebody was waiting on it). | ||
143 | * The default case (no contention) will result in NO | ||
144 | * jumps for both down() and up(). | ||
145 | */ | ||
146 | static inline void up(struct semaphore *sem) | ||
147 | { | ||
148 | register struct semaphore *sem1 __asm__ ("%a1") = sem; | ||
149 | |||
150 | __asm__ __volatile__( | ||
151 | "| atomic up operation\n\t" | ||
152 | "addql #1,%0@\n\t" | ||
153 | "jle 2f\n" | ||
154 | "1:\n" | ||
155 | LOCK_SECTION_START(".even\n\t") | ||
156 | "2:\t" | ||
157 | "pea 1b\n\t" | ||
158 | "jbra __up_wakeup\n" | ||
159 | LOCK_SECTION_END | ||
160 | : /* no outputs */ | ||
161 | : "a" (sem1) | ||
162 | : "memory"); | ||
163 | } | ||
164 | |||
165 | #endif /* __ASSEMBLY__ */ | ||
166 | |||
167 | #endif | ||