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-ppc/spinlock.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-ppc/spinlock.h')
-rw-r--r-- | include/asm-ppc/spinlock.h | 215 |
1 files changed, 215 insertions, 0 deletions
diff --git a/include/asm-ppc/spinlock.h b/include/asm-ppc/spinlock.h new file mode 100644 index 000000000000..909199aae104 --- /dev/null +++ b/include/asm-ppc/spinlock.h | |||
@@ -0,0 +1,215 @@ | |||
1 | #ifndef __ASM_SPINLOCK_H | ||
2 | #define __ASM_SPINLOCK_H | ||
3 | |||
4 | #include <asm/system.h> | ||
5 | |||
6 | /* | ||
7 | * Simple spin lock operations. | ||
8 | */ | ||
9 | |||
10 | typedef struct { | ||
11 | volatile unsigned long lock; | ||
12 | #ifdef CONFIG_DEBUG_SPINLOCK | ||
13 | volatile unsigned long owner_pc; | ||
14 | volatile unsigned long owner_cpu; | ||
15 | #endif | ||
16 | #ifdef CONFIG_PREEMPT | ||
17 | unsigned int break_lock; | ||
18 | #endif | ||
19 | } spinlock_t; | ||
20 | |||
21 | #ifdef __KERNEL__ | ||
22 | #ifdef CONFIG_DEBUG_SPINLOCK | ||
23 | #define SPINLOCK_DEBUG_INIT , 0, 0 | ||
24 | #else | ||
25 | #define SPINLOCK_DEBUG_INIT /* */ | ||
26 | #endif | ||
27 | |||
28 | #define SPIN_LOCK_UNLOCKED (spinlock_t) { 0 SPINLOCK_DEBUG_INIT } | ||
29 | |||
30 | #define spin_lock_init(x) do { *(x) = SPIN_LOCK_UNLOCKED; } while(0) | ||
31 | #define spin_is_locked(x) ((x)->lock != 0) | ||
32 | #define spin_unlock_wait(x) do { barrier(); } while(spin_is_locked(x)) | ||
33 | #define _raw_spin_lock_flags(lock, flags) _raw_spin_lock(lock) | ||
34 | |||
35 | #ifndef CONFIG_DEBUG_SPINLOCK | ||
36 | |||
37 | static inline void _raw_spin_lock(spinlock_t *lock) | ||
38 | { | ||
39 | unsigned long tmp; | ||
40 | |||
41 | __asm__ __volatile__( | ||
42 | "b 1f # spin_lock\n\ | ||
43 | 2: lwzx %0,0,%1\n\ | ||
44 | cmpwi 0,%0,0\n\ | ||
45 | bne+ 2b\n\ | ||
46 | 1: lwarx %0,0,%1\n\ | ||
47 | cmpwi 0,%0,0\n\ | ||
48 | bne- 2b\n" | ||
49 | PPC405_ERR77(0,%1) | ||
50 | " stwcx. %2,0,%1\n\ | ||
51 | bne- 2b\n\ | ||
52 | isync" | ||
53 | : "=&r"(tmp) | ||
54 | : "r"(&lock->lock), "r"(1) | ||
55 | : "cr0", "memory"); | ||
56 | } | ||
57 | |||
58 | static inline void _raw_spin_unlock(spinlock_t *lock) | ||
59 | { | ||
60 | __asm__ __volatile__("eieio # spin_unlock": : :"memory"); | ||
61 | lock->lock = 0; | ||
62 | } | ||
63 | |||
64 | #define _raw_spin_trylock(l) (!test_and_set_bit(0,&(l)->lock)) | ||
65 | |||
66 | #else | ||
67 | |||
68 | extern void _raw_spin_lock(spinlock_t *lock); | ||
69 | extern void _raw_spin_unlock(spinlock_t *lock); | ||
70 | extern int _raw_spin_trylock(spinlock_t *lock); | ||
71 | |||
72 | #endif | ||
73 | |||
74 | /* | ||
75 | * Read-write spinlocks, allowing multiple readers | ||
76 | * but only one writer. | ||
77 | * | ||
78 | * NOTE! it is quite common to have readers in interrupts | ||
79 | * but no interrupt writers. For those circumstances we | ||
80 | * can "mix" irq-safe locks - any writer needs to get a | ||
81 | * irq-safe write-lock, but readers can get non-irqsafe | ||
82 | * read-locks. | ||
83 | */ | ||
84 | typedef struct { | ||
85 | volatile signed int lock; | ||
86 | #ifdef CONFIG_PREEMPT | ||
87 | unsigned int break_lock; | ||
88 | #endif | ||
89 | } rwlock_t; | ||
90 | |||
91 | #define RW_LOCK_UNLOCKED (rwlock_t) { 0 } | ||
92 | #define rwlock_init(lp) do { *(lp) = RW_LOCK_UNLOCKED; } while(0) | ||
93 | |||
94 | #define read_can_lock(rw) ((rw)->lock >= 0) | ||
95 | #define write_can_lock(rw) (!(rw)->lock) | ||
96 | |||
97 | #ifndef CONFIG_DEBUG_SPINLOCK | ||
98 | |||
99 | static __inline__ int _raw_read_trylock(rwlock_t *rw) | ||
100 | { | ||
101 | signed int tmp; | ||
102 | |||
103 | __asm__ __volatile__( | ||
104 | "2: lwarx %0,0,%1 # read_trylock\n\ | ||
105 | addic. %0,%0,1\n\ | ||
106 | ble- 1f\n" | ||
107 | PPC405_ERR77(0,%1) | ||
108 | " stwcx. %0,0,%1\n\ | ||
109 | bne- 2b\n\ | ||
110 | isync\n\ | ||
111 | 1:" | ||
112 | : "=&r"(tmp) | ||
113 | : "r"(&rw->lock) | ||
114 | : "cr0", "memory"); | ||
115 | |||
116 | return tmp > 0; | ||
117 | } | ||
118 | |||
119 | static __inline__ void _raw_read_lock(rwlock_t *rw) | ||
120 | { | ||
121 | signed int tmp; | ||
122 | |||
123 | __asm__ __volatile__( | ||
124 | "b 2f # read_lock\n\ | ||
125 | 1: lwzx %0,0,%1\n\ | ||
126 | cmpwi 0,%0,0\n\ | ||
127 | blt+ 1b\n\ | ||
128 | 2: lwarx %0,0,%1\n\ | ||
129 | addic. %0,%0,1\n\ | ||
130 | ble- 1b\n" | ||
131 | PPC405_ERR77(0,%1) | ||
132 | " stwcx. %0,0,%1\n\ | ||
133 | bne- 2b\n\ | ||
134 | isync" | ||
135 | : "=&r"(tmp) | ||
136 | : "r"(&rw->lock) | ||
137 | : "cr0", "memory"); | ||
138 | } | ||
139 | |||
140 | static __inline__ void _raw_read_unlock(rwlock_t *rw) | ||
141 | { | ||
142 | signed int tmp; | ||
143 | |||
144 | __asm__ __volatile__( | ||
145 | "eieio # read_unlock\n\ | ||
146 | 1: lwarx %0,0,%1\n\ | ||
147 | addic %0,%0,-1\n" | ||
148 | PPC405_ERR77(0,%1) | ||
149 | " stwcx. %0,0,%1\n\ | ||
150 | bne- 1b" | ||
151 | : "=&r"(tmp) | ||
152 | : "r"(&rw->lock) | ||
153 | : "cr0", "memory"); | ||
154 | } | ||
155 | |||
156 | static __inline__ int _raw_write_trylock(rwlock_t *rw) | ||
157 | { | ||
158 | signed int tmp; | ||
159 | |||
160 | __asm__ __volatile__( | ||
161 | "2: lwarx %0,0,%1 # write_trylock\n\ | ||
162 | cmpwi 0,%0,0\n\ | ||
163 | bne- 1f\n" | ||
164 | PPC405_ERR77(0,%1) | ||
165 | " stwcx. %2,0,%1\n\ | ||
166 | bne- 2b\n\ | ||
167 | isync\n\ | ||
168 | 1:" | ||
169 | : "=&r"(tmp) | ||
170 | : "r"(&rw->lock), "r"(-1) | ||
171 | : "cr0", "memory"); | ||
172 | |||
173 | return tmp == 0; | ||
174 | } | ||
175 | |||
176 | static __inline__ void _raw_write_lock(rwlock_t *rw) | ||
177 | { | ||
178 | signed int tmp; | ||
179 | |||
180 | __asm__ __volatile__( | ||
181 | "b 2f # write_lock\n\ | ||
182 | 1: lwzx %0,0,%1\n\ | ||
183 | cmpwi 0,%0,0\n\ | ||
184 | bne+ 1b\n\ | ||
185 | 2: lwarx %0,0,%1\n\ | ||
186 | cmpwi 0,%0,0\n\ | ||
187 | bne- 1b\n" | ||
188 | PPC405_ERR77(0,%1) | ||
189 | " stwcx. %2,0,%1\n\ | ||
190 | bne- 2b\n\ | ||
191 | isync" | ||
192 | : "=&r"(tmp) | ||
193 | : "r"(&rw->lock), "r"(-1) | ||
194 | : "cr0", "memory"); | ||
195 | } | ||
196 | |||
197 | static __inline__ void _raw_write_unlock(rwlock_t *rw) | ||
198 | { | ||
199 | __asm__ __volatile__("eieio # write_unlock": : :"memory"); | ||
200 | rw->lock = 0; | ||
201 | } | ||
202 | |||
203 | #else | ||
204 | |||
205 | extern void _raw_read_lock(rwlock_t *rw); | ||
206 | extern void _raw_read_unlock(rwlock_t *rw); | ||
207 | extern void _raw_write_lock(rwlock_t *rw); | ||
208 | extern void _raw_write_unlock(rwlock_t *rw); | ||
209 | extern int _raw_read_trylock(rwlock_t *rw); | ||
210 | extern int _raw_write_trylock(rwlock_t *rw); | ||
211 | |||
212 | #endif | ||
213 | |||
214 | #endif /* __ASM_SPINLOCK_H */ | ||
215 | #endif /* __KERNEL__ */ | ||