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1da177e4 LT |
1 | #ifndef __LINUX_SPINLOCK_H |
2 | #define __LINUX_SPINLOCK_H | |
3 | ||
4 | /* | |
fb1c8f93 IM |
5 | * include/linux/spinlock.h - generic spinlock/rwlock declarations |
6 | * | |
7 | * here's the role of the various spinlock/rwlock related include files: | |
8 | * | |
9 | * on SMP builds: | |
10 | * | |
fb3a6bbc | 11 | * asm/spinlock_types.h: contains the arch_spinlock_t/arch_rwlock_t and the |
fb1c8f93 IM |
12 | * initializers |
13 | * | |
14 | * linux/spinlock_types.h: | |
15 | * defines the generic type and initializers | |
16 | * | |
0199c4e6 | 17 | * asm/spinlock.h: contains the arch_spin_*()/etc. lowlevel |
fb1c8f93 IM |
18 | * implementations, mostly inline assembly code |
19 | * | |
20 | * (also included on UP-debug builds:) | |
21 | * | |
22 | * linux/spinlock_api_smp.h: | |
23 | * contains the prototypes for the _spin_*() APIs. | |
24 | * | |
25 | * linux/spinlock.h: builds the final spin_*() APIs. | |
26 | * | |
27 | * on UP builds: | |
28 | * | |
29 | * linux/spinlock_type_up.h: | |
30 | * contains the generic, simplified UP spinlock type. | |
31 | * (which is an empty structure on non-debug builds) | |
32 | * | |
33 | * linux/spinlock_types.h: | |
34 | * defines the generic type and initializers | |
35 | * | |
36 | * linux/spinlock_up.h: | |
0199c4e6 | 37 | * contains the arch_spin_*()/etc. version of UP |
fb1c8f93 IM |
38 | * builds. (which are NOPs on non-debug, non-preempt |
39 | * builds) | |
40 | * | |
41 | * (included on UP-non-debug builds:) | |
42 | * | |
43 | * linux/spinlock_api_up.h: | |
44 | * builds the _spin_*() APIs. | |
45 | * | |
46 | * linux/spinlock.h: builds the final spin_*() APIs. | |
1da177e4 LT |
47 | */ |
48 | ||
3f307891 | 49 | #include <linux/typecheck.h> |
1da177e4 LT |
50 | #include <linux/preempt.h> |
51 | #include <linux/linkage.h> | |
52 | #include <linux/compiler.h> | |
53 | #include <linux/thread_info.h> | |
54 | #include <linux/kernel.h> | |
55 | #include <linux/stringify.h> | |
676dcb8b | 56 | #include <linux/bottom_half.h> |
1da177e4 | 57 | |
1da177e4 LT |
58 | #include <asm/system.h> |
59 | ||
60 | /* | |
61 | * Must define these before including other files, inline functions need them | |
62 | */ | |
75ddb0e8 | 63 | #define LOCK_SECTION_NAME ".text..lock."KBUILD_BASENAME |
1da177e4 LT |
64 | |
65 | #define LOCK_SECTION_START(extra) \ | |
66 | ".subsection 1\n\t" \ | |
67 | extra \ | |
68 | ".ifndef " LOCK_SECTION_NAME "\n\t" \ | |
69 | LOCK_SECTION_NAME ":\n\t" \ | |
70 | ".endif\n" | |
71 | ||
72 | #define LOCK_SECTION_END \ | |
73 | ".previous\n\t" | |
74 | ||
ec701584 | 75 | #define __lockfunc __attribute__((section(".spinlock.text"))) |
1da177e4 LT |
76 | |
77 | /* | |
fb3a6bbc | 78 | * Pull the arch_spinlock_t and arch_rwlock_t definitions: |
1da177e4 | 79 | */ |
fb1c8f93 | 80 | #include <linux/spinlock_types.h> |
1da177e4 | 81 | |
1da177e4 | 82 | /* |
c2f21ce2 | 83 | * Pull the arch_spin*() functions/declarations (UP-nondebug doesnt need them): |
1da177e4 | 84 | */ |
8a25d5de | 85 | #ifdef CONFIG_SMP |
fb1c8f93 | 86 | # include <asm/spinlock.h> |
1da177e4 | 87 | #else |
fb1c8f93 | 88 | # include <linux/spinlock_up.h> |
1da177e4 LT |
89 | #endif |
90 | ||
8a25d5de | 91 | #ifdef CONFIG_DEBUG_SPINLOCK |
c2f21ce2 TG |
92 | extern void __raw_spin_lock_init(raw_spinlock_t *lock, const char *name, |
93 | struct lock_class_key *key); | |
94 | # define raw_spin_lock_init(lock) \ | |
8a25d5de IM |
95 | do { \ |
96 | static struct lock_class_key __key; \ | |
97 | \ | |
c2f21ce2 | 98 | __raw_spin_lock_init((lock), #lock, &__key); \ |
8a25d5de IM |
99 | } while (0) |
100 | ||
101 | #else | |
c2f21ce2 TG |
102 | # define raw_spin_lock_init(lock) \ |
103 | do { *(lock) = __RAW_SPIN_LOCK_UNLOCKED(lock); } while (0) | |
8a25d5de IM |
104 | #endif |
105 | ||
c2f21ce2 | 106 | #define raw_spin_is_locked(lock) arch_spin_is_locked(&(lock)->raw_lock) |
fb1c8f93 | 107 | |
95c354fe | 108 | #ifdef CONFIG_GENERIC_LOCKBREAK |
c2f21ce2 | 109 | #define raw_spin_is_contended(lock) ((lock)->break_lock) |
95c354fe | 110 | #else |
a5ef7ca0 | 111 | |
0199c4e6 | 112 | #ifdef arch_spin_is_contended |
c2f21ce2 | 113 | #define raw_spin_is_contended(lock) arch_spin_is_contended(&(lock)->raw_lock) |
a5ef7ca0 | 114 | #else |
c2f21ce2 | 115 | #define raw_spin_is_contended(lock) (((void)(lock), 0)) |
0199c4e6 | 116 | #endif /*arch_spin_is_contended*/ |
95c354fe NP |
117 | #endif |
118 | ||
ad462769 JO |
119 | /* The lock does not imply full memory barrier. */ |
120 | #ifndef ARCH_HAS_SMP_MB_AFTER_LOCK | |
121 | static inline void smp_mb__after_lock(void) { smp_mb(); } | |
122 | #endif | |
123 | ||
fb1c8f93 | 124 | /** |
c2f21ce2 | 125 | * raw_spin_unlock_wait - wait until the spinlock gets unlocked |
fb1c8f93 IM |
126 | * @lock: the spinlock in question. |
127 | */ | |
c2f21ce2 | 128 | #define raw_spin_unlock_wait(lock) arch_spin_unlock_wait(&(lock)->raw_lock) |
fb1c8f93 | 129 | |
fb1c8f93 | 130 | #ifdef CONFIG_DEBUG_SPINLOCK |
b97c4bc1 | 131 | extern void do_raw_spin_lock(raw_spinlock_t *lock) __acquires(lock); |
9828ea9d TG |
132 | #define do_raw_spin_lock_flags(lock, flags) do_raw_spin_lock(lock) |
133 | extern int do_raw_spin_trylock(raw_spinlock_t *lock); | |
b97c4bc1 | 134 | extern void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock); |
fb1c8f93 | 135 | #else |
b97c4bc1 | 136 | static inline void do_raw_spin_lock(raw_spinlock_t *lock) __acquires(lock) |
c2f21ce2 | 137 | { |
b97c4bc1 | 138 | __acquire(lock); |
c2f21ce2 TG |
139 | arch_spin_lock(&lock->raw_lock); |
140 | } | |
141 | ||
142 | static inline void | |
b97c4bc1 | 143 | do_raw_spin_lock_flags(raw_spinlock_t *lock, unsigned long *flags) __acquires(lock) |
c2f21ce2 | 144 | { |
b97c4bc1 | 145 | __acquire(lock); |
c2f21ce2 TG |
146 | arch_spin_lock_flags(&lock->raw_lock, *flags); |
147 | } | |
148 | ||
9828ea9d | 149 | static inline int do_raw_spin_trylock(raw_spinlock_t *lock) |
c2f21ce2 TG |
150 | { |
151 | return arch_spin_trylock(&(lock)->raw_lock); | |
152 | } | |
153 | ||
b97c4bc1 | 154 | static inline void do_raw_spin_unlock(raw_spinlock_t *lock) __releases(lock) |
c2f21ce2 TG |
155 | { |
156 | arch_spin_unlock(&lock->raw_lock); | |
b97c4bc1 | 157 | __release(lock); |
c2f21ce2 | 158 | } |
fb1c8f93 | 159 | #endif |
1da177e4 | 160 | |
1da177e4 | 161 | /* |
ef12f109 TG |
162 | * Define the various spin_lock methods. Note we define these |
163 | * regardless of whether CONFIG_SMP or CONFIG_PREEMPT are set. The | |
164 | * various methods are defined as nops in the case they are not | |
165 | * required. | |
1da177e4 | 166 | */ |
9c1721aa | 167 | #define raw_spin_trylock(lock) __cond_lock(lock, _raw_spin_trylock(lock)) |
1da177e4 | 168 | |
9c1721aa | 169 | #define raw_spin_lock(lock) _raw_spin_lock(lock) |
8a25d5de IM |
170 | |
171 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
9c1721aa TG |
172 | # define raw_spin_lock_nested(lock, subclass) \ |
173 | _raw_spin_lock_nested(lock, subclass) | |
174 | ||
c2f21ce2 | 175 | # define raw_spin_lock_nest_lock(lock, nest_lock) \ |
b7d39aff PZ |
176 | do { \ |
177 | typecheck(struct lockdep_map *, &(nest_lock)->dep_map);\ | |
9c1721aa | 178 | _raw_spin_lock_nest_lock(lock, &(nest_lock)->dep_map); \ |
b7d39aff | 179 | } while (0) |
8a25d5de | 180 | #else |
9c1721aa TG |
181 | # define raw_spin_lock_nested(lock, subclass) _raw_spin_lock(lock) |
182 | # define raw_spin_lock_nest_lock(lock, nest_lock) _raw_spin_lock(lock) | |
8a25d5de IM |
183 | #endif |
184 | ||
fb1c8f93 | 185 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) |
b8e6ec86 | 186 | |
c2f21ce2 | 187 | #define raw_spin_lock_irqsave(lock, flags) \ |
3f307891 SR |
188 | do { \ |
189 | typecheck(unsigned long, flags); \ | |
9c1721aa | 190 | flags = _raw_spin_lock_irqsave(lock); \ |
3f307891 | 191 | } while (0) |
cfd3ef23 AV |
192 | |
193 | #ifdef CONFIG_DEBUG_LOCK_ALLOC | |
c2f21ce2 | 194 | #define raw_spin_lock_irqsave_nested(lock, flags, subclass) \ |
3f307891 SR |
195 | do { \ |
196 | typecheck(unsigned long, flags); \ | |
9c1721aa | 197 | flags = _raw_spin_lock_irqsave_nested(lock, subclass); \ |
3f307891 | 198 | } while (0) |
cfd3ef23 | 199 | #else |
c2f21ce2 | 200 | #define raw_spin_lock_irqsave_nested(lock, flags, subclass) \ |
3f307891 SR |
201 | do { \ |
202 | typecheck(unsigned long, flags); \ | |
9c1721aa | 203 | flags = _raw_spin_lock_irqsave(lock); \ |
3f307891 | 204 | } while (0) |
cfd3ef23 AV |
205 | #endif |
206 | ||
1da177e4 | 207 | #else |
b8e6ec86 | 208 | |
c2f21ce2 | 209 | #define raw_spin_lock_irqsave(lock, flags) \ |
3f307891 SR |
210 | do { \ |
211 | typecheck(unsigned long, flags); \ | |
9c1721aa | 212 | _raw_spin_lock_irqsave(lock, flags); \ |
3f307891 | 213 | } while (0) |
ef12f109 | 214 | |
c2f21ce2 TG |
215 | #define raw_spin_lock_irqsave_nested(lock, flags, subclass) \ |
216 | raw_spin_lock_irqsave(lock, flags) | |
cfd3ef23 | 217 | |
1da177e4 LT |
218 | #endif |
219 | ||
9c1721aa TG |
220 | #define raw_spin_lock_irq(lock) _raw_spin_lock_irq(lock) |
221 | #define raw_spin_lock_bh(lock) _raw_spin_lock_bh(lock) | |
222 | #define raw_spin_unlock(lock) _raw_spin_unlock(lock) | |
223 | #define raw_spin_unlock_irq(lock) _raw_spin_unlock_irq(lock) | |
1da177e4 | 224 | |
c2f21ce2 TG |
225 | #define raw_spin_unlock_irqrestore(lock, flags) \ |
226 | do { \ | |
227 | typecheck(unsigned long, flags); \ | |
9c1721aa | 228 | _raw_spin_unlock_irqrestore(lock, flags); \ |
3f307891 | 229 | } while (0) |
9c1721aa | 230 | #define raw_spin_unlock_bh(lock) _raw_spin_unlock_bh(lock) |
1da177e4 | 231 | |
9c1721aa TG |
232 | #define raw_spin_trylock_bh(lock) \ |
233 | __cond_lock(lock, _raw_spin_trylock_bh(lock)) | |
1da177e4 | 234 | |
c2f21ce2 | 235 | #define raw_spin_trylock_irq(lock) \ |
1da177e4 LT |
236 | ({ \ |
237 | local_irq_disable(); \ | |
c2f21ce2 | 238 | raw_spin_trylock(lock) ? \ |
fb1c8f93 | 239 | 1 : ({ local_irq_enable(); 0; }); \ |
1da177e4 LT |
240 | }) |
241 | ||
c2f21ce2 | 242 | #define raw_spin_trylock_irqsave(lock, flags) \ |
1da177e4 LT |
243 | ({ \ |
244 | local_irq_save(flags); \ | |
c2f21ce2 | 245 | raw_spin_trylock(lock) ? \ |
fb1c8f93 | 246 | 1 : ({ local_irq_restore(flags); 0; }); \ |
1da177e4 LT |
247 | }) |
248 | ||
c2f21ce2 TG |
249 | /** |
250 | * raw_spin_can_lock - would raw_spin_trylock() succeed? | |
251 | * @lock: the spinlock in question. | |
252 | */ | |
253 | #define raw_spin_can_lock(lock) (!raw_spin_is_locked(lock)) | |
254 | ||
255 | /* Include rwlock functions */ | |
256 | #include <linux/rwlock.h> | |
257 | ||
258 | /* | |
259 | * Pull the _spin_*()/_read_*()/_write_*() functions/declarations: | |
260 | */ | |
261 | #if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) | |
262 | # include <linux/spinlock_api_smp.h> | |
263 | #else | |
264 | # include <linux/spinlock_api_up.h> | |
265 | #endif | |
266 | ||
267 | /* | |
268 | * Map the spin_lock functions to the raw variants for PREEMPT_RT=n | |
269 | */ | |
270 | ||
271 | static inline raw_spinlock_t *spinlock_check(spinlock_t *lock) | |
272 | { | |
273 | return &lock->rlock; | |
274 | } | |
275 | ||
276 | #define spin_lock_init(_lock) \ | |
277 | do { \ | |
278 | spinlock_check(_lock); \ | |
279 | raw_spin_lock_init(&(_lock)->rlock); \ | |
280 | } while (0) | |
281 | ||
282 | static inline void spin_lock(spinlock_t *lock) | |
283 | { | |
284 | raw_spin_lock(&lock->rlock); | |
285 | } | |
286 | ||
287 | static inline void spin_lock_bh(spinlock_t *lock) | |
288 | { | |
289 | raw_spin_lock_bh(&lock->rlock); | |
290 | } | |
291 | ||
292 | static inline int spin_trylock(spinlock_t *lock) | |
293 | { | |
294 | return raw_spin_trylock(&lock->rlock); | |
295 | } | |
296 | ||
297 | #define spin_lock_nested(lock, subclass) \ | |
298 | do { \ | |
299 | raw_spin_lock_nested(spinlock_check(lock), subclass); \ | |
300 | } while (0) | |
301 | ||
302 | #define spin_lock_nest_lock(lock, nest_lock) \ | |
303 | do { \ | |
304 | raw_spin_lock_nest_lock(spinlock_check(lock), nest_lock); \ | |
305 | } while (0) | |
306 | ||
307 | static inline void spin_lock_irq(spinlock_t *lock) | |
308 | { | |
309 | raw_spin_lock_irq(&lock->rlock); | |
310 | } | |
311 | ||
312 | #define spin_lock_irqsave(lock, flags) \ | |
313 | do { \ | |
314 | raw_spin_lock_irqsave(spinlock_check(lock), flags); \ | |
315 | } while (0) | |
316 | ||
317 | #define spin_lock_irqsave_nested(lock, flags, subclass) \ | |
318 | do { \ | |
319 | raw_spin_lock_irqsave_nested(spinlock_check(lock), flags, subclass); \ | |
320 | } while (0) | |
321 | ||
322 | static inline void spin_unlock(spinlock_t *lock) | |
323 | { | |
324 | raw_spin_unlock(&lock->rlock); | |
325 | } | |
326 | ||
327 | static inline void spin_unlock_bh(spinlock_t *lock) | |
328 | { | |
329 | raw_spin_unlock_bh(&lock->rlock); | |
330 | } | |
331 | ||
332 | static inline void spin_unlock_irq(spinlock_t *lock) | |
333 | { | |
334 | raw_spin_unlock_irq(&lock->rlock); | |
335 | } | |
336 | ||
337 | static inline void spin_unlock_irqrestore(spinlock_t *lock, unsigned long flags) | |
338 | { | |
339 | raw_spin_unlock_irqrestore(&lock->rlock, flags); | |
340 | } | |
341 | ||
342 | static inline int spin_trylock_bh(spinlock_t *lock) | |
343 | { | |
344 | return raw_spin_trylock_bh(&lock->rlock); | |
345 | } | |
346 | ||
347 | static inline int spin_trylock_irq(spinlock_t *lock) | |
348 | { | |
349 | return raw_spin_trylock_irq(&lock->rlock); | |
350 | } | |
351 | ||
352 | #define spin_trylock_irqsave(lock, flags) \ | |
353 | ({ \ | |
354 | raw_spin_trylock_irqsave(spinlock_check(lock), flags); \ | |
355 | }) | |
356 | ||
357 | static inline void spin_unlock_wait(spinlock_t *lock) | |
358 | { | |
359 | raw_spin_unlock_wait(&lock->rlock); | |
360 | } | |
361 | ||
362 | static inline int spin_is_locked(spinlock_t *lock) | |
363 | { | |
364 | return raw_spin_is_locked(&lock->rlock); | |
365 | } | |
366 | ||
367 | static inline int spin_is_contended(spinlock_t *lock) | |
368 | { | |
369 | return raw_spin_is_contended(&lock->rlock); | |
370 | } | |
371 | ||
372 | static inline int spin_can_lock(spinlock_t *lock) | |
373 | { | |
374 | return raw_spin_can_lock(&lock->rlock); | |
375 | } | |
376 | ||
377 | static inline void assert_spin_locked(spinlock_t *lock) | |
378 | { | |
379 | assert_raw_spin_locked(&lock->rlock); | |
380 | } | |
381 | ||
1da177e4 | 382 | /* |
fb1c8f93 IM |
383 | * Pull the atomic_t declaration: |
384 | * (asm-mips/atomic.h needs above definitions) | |
1da177e4 | 385 | */ |
fb1c8f93 IM |
386 | #include <asm/atomic.h> |
387 | /** | |
388 | * atomic_dec_and_lock - lock on reaching reference count zero | |
389 | * @atomic: the atomic counter | |
390 | * @lock: the spinlock in question | |
dc07e721 BF |
391 | * |
392 | * Decrements @atomic by 1. If the result is 0, returns true and locks | |
393 | * @lock. Returns false for all other cases. | |
1da177e4 | 394 | */ |
fb1c8f93 IM |
395 | extern int _atomic_dec_and_lock(atomic_t *atomic, spinlock_t *lock); |
396 | #define atomic_dec_and_lock(atomic, lock) \ | |
dcc8e559 | 397 | __cond_lock(lock, _atomic_dec_and_lock(atomic, lock)) |
1da177e4 | 398 | |
1da177e4 | 399 | #endif /* __LINUX_SPINLOCK_H */ |