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1da177e4 LT |
1 | #ifndef _LINUX_WAIT_H |
2 | #define _LINUX_WAIT_H | |
fb869b6e IM |
3 | /* |
4 | * Linux wait queue related types and methods | |
5 | */ | |
1da177e4 LT |
6 | #include <linux/list.h> |
7 | #include <linux/stddef.h> | |
8 | #include <linux/spinlock.h> | |
1da177e4 | 9 | #include <asm/current.h> |
607ca46e | 10 | #include <uapi/linux/wait.h> |
1da177e4 LT |
11 | |
12 | typedef struct __wait_queue wait_queue_t; | |
7d478721 PZ |
13 | typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int flags, void *key); |
14 | int default_wake_function(wait_queue_t *wait, unsigned mode, int flags, void *key); | |
1da177e4 | 15 | |
61ada528 PZ |
16 | /* __wait_queue::flags */ |
17 | #define WQ_FLAG_EXCLUSIVE 0x01 | |
18 | #define WQ_FLAG_WOKEN 0x02 | |
19 | ||
1da177e4 | 20 | struct __wait_queue { |
fb869b6e | 21 | unsigned int flags; |
fb869b6e IM |
22 | void *private; |
23 | wait_queue_func_t func; | |
24 | struct list_head task_list; | |
1da177e4 LT |
25 | }; |
26 | ||
27 | struct wait_bit_key { | |
fb869b6e IM |
28 | void *flags; |
29 | int bit_nr; | |
30 | #define WAIT_ATOMIC_T_BIT_NR -1 | |
cbbce822 | 31 | unsigned long timeout; |
1da177e4 LT |
32 | }; |
33 | ||
34 | struct wait_bit_queue { | |
fb869b6e IM |
35 | struct wait_bit_key key; |
36 | wait_queue_t wait; | |
1da177e4 LT |
37 | }; |
38 | ||
39 | struct __wait_queue_head { | |
fb869b6e IM |
40 | spinlock_t lock; |
41 | struct list_head task_list; | |
1da177e4 LT |
42 | }; |
43 | typedef struct __wait_queue_head wait_queue_head_t; | |
44 | ||
8c65b4a6 | 45 | struct task_struct; |
1da177e4 LT |
46 | |
47 | /* | |
48 | * Macros for declaration and initialisaton of the datatypes | |
49 | */ | |
50 | ||
51 | #define __WAITQUEUE_INITIALIZER(name, tsk) { \ | |
c43dc2fd | 52 | .private = tsk, \ |
1da177e4 LT |
53 | .func = default_wake_function, \ |
54 | .task_list = { NULL, NULL } } | |
55 | ||
56 | #define DECLARE_WAITQUEUE(name, tsk) \ | |
57 | wait_queue_t name = __WAITQUEUE_INITIALIZER(name, tsk) | |
58 | ||
59 | #define __WAIT_QUEUE_HEAD_INITIALIZER(name) { \ | |
e4d91918 | 60 | .lock = __SPIN_LOCK_UNLOCKED(name.lock), \ |
1da177e4 LT |
61 | .task_list = { &(name).task_list, &(name).task_list } } |
62 | ||
63 | #define DECLARE_WAIT_QUEUE_HEAD(name) \ | |
64 | wait_queue_head_t name = __WAIT_QUEUE_HEAD_INITIALIZER(name) | |
65 | ||
66 | #define __WAIT_BIT_KEY_INITIALIZER(word, bit) \ | |
67 | { .flags = word, .bit_nr = bit, } | |
68 | ||
cb65537e DH |
69 | #define __WAIT_ATOMIC_T_KEY_INITIALIZER(p) \ |
70 | { .flags = p, .bit_nr = WAIT_ATOMIC_T_BIT_NR, } | |
71 | ||
f07fdec5 | 72 | extern void __init_waitqueue_head(wait_queue_head_t *q, const char *name, struct lock_class_key *); |
2fc39111 PZ |
73 | |
74 | #define init_waitqueue_head(q) \ | |
75 | do { \ | |
76 | static struct lock_class_key __key; \ | |
77 | \ | |
f07fdec5 | 78 | __init_waitqueue_head((q), #q, &__key); \ |
2fc39111 | 79 | } while (0) |
1da177e4 | 80 | |
7259f0d0 PZ |
81 | #ifdef CONFIG_LOCKDEP |
82 | # define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \ | |
83 | ({ init_waitqueue_head(&name); name; }) | |
84 | # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \ | |
85 | wait_queue_head_t name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) | |
86 | #else | |
87 | # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name) | |
88 | #endif | |
89 | ||
1da177e4 LT |
90 | static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p) |
91 | { | |
fb869b6e IM |
92 | q->flags = 0; |
93 | q->private = p; | |
94 | q->func = default_wake_function; | |
1da177e4 LT |
95 | } |
96 | ||
fb869b6e IM |
97 | static inline void |
98 | init_waitqueue_func_entry(wait_queue_t *q, wait_queue_func_t func) | |
1da177e4 | 99 | { |
fb869b6e IM |
100 | q->flags = 0; |
101 | q->private = NULL; | |
102 | q->func = func; | |
1da177e4 LT |
103 | } |
104 | ||
69e51e92 PZ |
105 | /** |
106 | * waitqueue_active -- locklessly test for waiters on the queue | |
107 | * @q: the waitqueue to test for waiters | |
108 | * | |
109 | * returns true if the wait list is not empty | |
110 | * | |
111 | * NOTE: this function is lockless and requires care, incorrect usage _will_ | |
112 | * lead to sporadic and non-obvious failure. | |
113 | * | |
114 | * Use either while holding wait_queue_head_t::lock or when used for wakeups | |
115 | * with an extra smp_mb() like: | |
116 | * | |
117 | * CPU0 - waker CPU1 - waiter | |
118 | * | |
119 | * for (;;) { | |
120 | * @cond = true; prepare_to_wait(&wq, &wait, state); | |
121 | * smp_mb(); // smp_mb() from set_current_state() | |
122 | * if (waitqueue_active(wq)) if (@cond) | |
123 | * wake_up(wq); break; | |
124 | * schedule(); | |
125 | * } | |
126 | * finish_wait(&wq, &wait); | |
127 | * | |
128 | * Because without the explicit smp_mb() it's possible for the | |
129 | * waitqueue_active() load to get hoisted over the @cond store such that we'll | |
130 | * observe an empty wait list while the waiter might not observe @cond. | |
131 | * | |
132 | * Also note that this 'optimization' trades a spin_lock() for an smp_mb(), | |
133 | * which (when the lock is uncontended) are of roughly equal cost. | |
134 | */ | |
1da177e4 LT |
135 | static inline int waitqueue_active(wait_queue_head_t *q) |
136 | { | |
137 | return !list_empty(&q->task_list); | |
138 | } | |
139 | ||
1ce0bf50 HX |
140 | /** |
141 | * wq_has_sleeper - check if there are any waiting processes | |
142 | * @wq: wait queue head | |
143 | * | |
144 | * Returns true if wq has waiting processes | |
145 | * | |
146 | * Please refer to the comment for waitqueue_active. | |
147 | */ | |
148 | static inline bool wq_has_sleeper(wait_queue_head_t *wq) | |
149 | { | |
150 | /* | |
151 | * We need to be sure we are in sync with the | |
152 | * add_wait_queue modifications to the wait queue. | |
153 | * | |
154 | * This memory barrier should be paired with one on the | |
155 | * waiting side. | |
156 | */ | |
157 | smp_mb(); | |
158 | return waitqueue_active(wq); | |
159 | } | |
160 | ||
b3c97528 HH |
161 | extern void add_wait_queue(wait_queue_head_t *q, wait_queue_t *wait); |
162 | extern void add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t *wait); | |
163 | extern void remove_wait_queue(wait_queue_head_t *q, wait_queue_t *wait); | |
1da177e4 LT |
164 | |
165 | static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new) | |
166 | { | |
167 | list_add(&new->task_list, &head->task_list); | |
168 | } | |
169 | ||
170 | /* | |
171 | * Used for wake-one threads: | |
172 | */ | |
fb869b6e IM |
173 | static inline void |
174 | __add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t *wait) | |
a93d2f17 CG |
175 | { |
176 | wait->flags |= WQ_FLAG_EXCLUSIVE; | |
177 | __add_wait_queue(q, wait); | |
178 | } | |
179 | ||
1da177e4 | 180 | static inline void __add_wait_queue_tail(wait_queue_head_t *head, |
a93d2f17 | 181 | wait_queue_t *new) |
1da177e4 LT |
182 | { |
183 | list_add_tail(&new->task_list, &head->task_list); | |
184 | } | |
185 | ||
fb869b6e IM |
186 | static inline void |
187 | __add_wait_queue_tail_exclusive(wait_queue_head_t *q, wait_queue_t *wait) | |
a93d2f17 CG |
188 | { |
189 | wait->flags |= WQ_FLAG_EXCLUSIVE; | |
190 | __add_wait_queue_tail(q, wait); | |
191 | } | |
192 | ||
fb869b6e IM |
193 | static inline void |
194 | __remove_wait_queue(wait_queue_head_t *head, wait_queue_t *old) | |
1da177e4 LT |
195 | { |
196 | list_del(&old->task_list); | |
197 | } | |
198 | ||
dfd01f02 | 199 | typedef int wait_bit_action_f(struct wait_bit_key *, int mode); |
b3c97528 | 200 | void __wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *key); |
ac5be6b4 | 201 | void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key); |
fb869b6e | 202 | void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr, void *key); |
63b20011 | 203 | void __wake_up_locked(wait_queue_head_t *q, unsigned int mode, int nr); |
4ede816a | 204 | void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr); |
b3c97528 | 205 | void __wake_up_bit(wait_queue_head_t *, void *, int); |
c1221321 N |
206 | int __wait_on_bit(wait_queue_head_t *, struct wait_bit_queue *, wait_bit_action_f *, unsigned); |
207 | int __wait_on_bit_lock(wait_queue_head_t *, struct wait_bit_queue *, wait_bit_action_f *, unsigned); | |
b3c97528 | 208 | void wake_up_bit(void *, int); |
cb65537e | 209 | void wake_up_atomic_t(atomic_t *); |
c1221321 | 210 | int out_of_line_wait_on_bit(void *, int, wait_bit_action_f *, unsigned); |
cbbce822 | 211 | int out_of_line_wait_on_bit_timeout(void *, int, wait_bit_action_f *, unsigned, unsigned long); |
c1221321 | 212 | int out_of_line_wait_on_bit_lock(void *, int, wait_bit_action_f *, unsigned); |
cb65537e | 213 | int out_of_line_wait_on_atomic_t(atomic_t *, int (*)(atomic_t *), unsigned); |
b3c97528 | 214 | wait_queue_head_t *bit_waitqueue(void *, int); |
1da177e4 | 215 | |
e64d66c8 MW |
216 | #define wake_up(x) __wake_up(x, TASK_NORMAL, 1, NULL) |
217 | #define wake_up_nr(x, nr) __wake_up(x, TASK_NORMAL, nr, NULL) | |
218 | #define wake_up_all(x) __wake_up(x, TASK_NORMAL, 0, NULL) | |
63b20011 TG |
219 | #define wake_up_locked(x) __wake_up_locked((x), TASK_NORMAL, 1) |
220 | #define wake_up_all_locked(x) __wake_up_locked((x), TASK_NORMAL, 0) | |
e64d66c8 | 221 | |
1da177e4 LT |
222 | #define wake_up_interruptible(x) __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL) |
223 | #define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL) | |
224 | #define wake_up_interruptible_all(x) __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL) | |
e64d66c8 | 225 | #define wake_up_interruptible_sync(x) __wake_up_sync((x), TASK_INTERRUPTIBLE, 1) |
1da177e4 | 226 | |
0ccf831c | 227 | /* |
c0da3775 | 228 | * Wakeup macros to be used to report events to the targets. |
0ccf831c | 229 | */ |
fb869b6e | 230 | #define wake_up_poll(x, m) \ |
c0da3775 | 231 | __wake_up(x, TASK_NORMAL, 1, (void *) (m)) |
fb869b6e | 232 | #define wake_up_locked_poll(x, m) \ |
ac5be6b4 | 233 | __wake_up_locked_key((x), TASK_NORMAL, (void *) (m)) |
fb869b6e | 234 | #define wake_up_interruptible_poll(x, m) \ |
c0da3775 DL |
235 | __wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m)) |
236 | #define wake_up_interruptible_sync_poll(x, m) \ | |
237 | __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m)) | |
0ccf831c | 238 | |
35a2af94 | 239 | #define ___wait_cond_timeout(condition) \ |
2953ef24 | 240 | ({ \ |
fb869b6e IM |
241 | bool __cond = (condition); \ |
242 | if (__cond && !__ret) \ | |
243 | __ret = 1; \ | |
244 | __cond || !__ret; \ | |
2953ef24 PZ |
245 | }) |
246 | ||
c2d81644 ON |
247 | #define ___wait_is_interruptible(state) \ |
248 | (!__builtin_constant_p(state) || \ | |
249 | state == TASK_INTERRUPTIBLE || state == TASK_KILLABLE) \ | |
41a1431b | 250 | |
0176beaf ON |
251 | extern void init_wait_entry(wait_queue_t *__wait, int flags); |
252 | ||
8b32201d PZ |
253 | /* |
254 | * The below macro ___wait_event() has an explicit shadow of the __ret | |
255 | * variable when used from the wait_event_*() macros. | |
256 | * | |
257 | * This is so that both can use the ___wait_cond_timeout() construct | |
258 | * to wrap the condition. | |
259 | * | |
260 | * The type inconsistency of the wait_event_*() __ret variable is also | |
261 | * on purpose; we use long where we can return timeout values and int | |
262 | * otherwise. | |
263 | */ | |
264 | ||
41a1431b | 265 | #define ___wait_event(wq, condition, state, exclusive, ret, cmd) \ |
35a2af94 | 266 | ({ \ |
41a1431b | 267 | __label__ __out; \ |
c2d81644 | 268 | wait_queue_t __wait; \ |
8b32201d | 269 | long __ret = ret; /* explicit shadow */ \ |
41a1431b | 270 | \ |
0176beaf | 271 | init_wait_entry(&__wait, exclusive ? WQ_FLAG_EXCLUSIVE : 0); \ |
41a1431b | 272 | for (;;) { \ |
c2d81644 | 273 | long __int = prepare_to_wait_event(&wq, &__wait, state);\ |
41a1431b PZ |
274 | \ |
275 | if (condition) \ | |
276 | break; \ | |
277 | \ | |
c2d81644 ON |
278 | if (___wait_is_interruptible(state) && __int) { \ |
279 | __ret = __int; \ | |
b1ea06a9 | 280 | goto __out; \ |
41a1431b PZ |
281 | } \ |
282 | \ | |
283 | cmd; \ | |
284 | } \ | |
285 | finish_wait(&wq, &__wait); \ | |
35a2af94 PZ |
286 | __out: __ret; \ |
287 | }) | |
41a1431b | 288 | |
fb869b6e | 289 | #define __wait_event(wq, condition) \ |
35a2af94 PZ |
290 | (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ |
291 | schedule()) | |
1da177e4 LT |
292 | |
293 | /** | |
294 | * wait_event - sleep until a condition gets true | |
295 | * @wq: the waitqueue to wait on | |
296 | * @condition: a C expression for the event to wait for | |
297 | * | |
298 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
299 | * @condition evaluates to true. The @condition is checked each time | |
300 | * the waitqueue @wq is woken up. | |
301 | * | |
302 | * wake_up() has to be called after changing any variable that could | |
303 | * change the result of the wait condition. | |
304 | */ | |
fb869b6e | 305 | #define wait_event(wq, condition) \ |
1da177e4 | 306 | do { \ |
e22b886a | 307 | might_sleep(); \ |
fb869b6e | 308 | if (condition) \ |
1da177e4 LT |
309 | break; \ |
310 | __wait_event(wq, condition); \ | |
311 | } while (0) | |
312 | ||
2c561246 PZ |
313 | #define __io_wait_event(wq, condition) \ |
314 | (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ | |
315 | io_schedule()) | |
316 | ||
317 | /* | |
318 | * io_wait_event() -- like wait_event() but with io_schedule() | |
319 | */ | |
320 | #define io_wait_event(wq, condition) \ | |
321 | do { \ | |
322 | might_sleep(); \ | |
323 | if (condition) \ | |
324 | break; \ | |
325 | __io_wait_event(wq, condition); \ | |
326 | } while (0) | |
327 | ||
36df04bc PZ |
328 | #define __wait_event_freezable(wq, condition) \ |
329 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ | |
330 | schedule(); try_to_freeze()) | |
331 | ||
332 | /** | |
f4bcfa1d | 333 | * wait_event_freezable - sleep (or freeze) until a condition gets true |
36df04bc PZ |
334 | * @wq: the waitqueue to wait on |
335 | * @condition: a C expression for the event to wait for | |
336 | * | |
337 | * The process is put to sleep (TASK_INTERRUPTIBLE -- so as not to contribute | |
338 | * to system load) until the @condition evaluates to true. The | |
339 | * @condition is checked each time the waitqueue @wq is woken up. | |
340 | * | |
341 | * wake_up() has to be called after changing any variable that could | |
342 | * change the result of the wait condition. | |
343 | */ | |
344 | #define wait_event_freezable(wq, condition) \ | |
345 | ({ \ | |
346 | int __ret = 0; \ | |
347 | might_sleep(); \ | |
348 | if (!(condition)) \ | |
349 | __ret = __wait_event_freezable(wq, condition); \ | |
350 | __ret; \ | |
351 | }) | |
352 | ||
35a2af94 PZ |
353 | #define __wait_event_timeout(wq, condition, timeout) \ |
354 | ___wait_event(wq, ___wait_cond_timeout(condition), \ | |
355 | TASK_UNINTERRUPTIBLE, 0, timeout, \ | |
356 | __ret = schedule_timeout(__ret)) | |
1da177e4 LT |
357 | |
358 | /** | |
359 | * wait_event_timeout - sleep until a condition gets true or a timeout elapses | |
360 | * @wq: the waitqueue to wait on | |
361 | * @condition: a C expression for the event to wait for | |
362 | * @timeout: timeout, in jiffies | |
363 | * | |
364 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
365 | * @condition evaluates to true. The @condition is checked each time | |
366 | * the waitqueue @wq is woken up. | |
367 | * | |
368 | * wake_up() has to be called after changing any variable that could | |
369 | * change the result of the wait condition. | |
370 | * | |
6b44f519 SD |
371 | * Returns: |
372 | * 0 if the @condition evaluated to %false after the @timeout elapsed, | |
373 | * 1 if the @condition evaluated to %true after the @timeout elapsed, | |
374 | * or the remaining jiffies (at least 1) if the @condition evaluated | |
375 | * to %true before the @timeout elapsed. | |
1da177e4 LT |
376 | */ |
377 | #define wait_event_timeout(wq, condition, timeout) \ | |
378 | ({ \ | |
379 | long __ret = timeout; \ | |
e22b886a | 380 | might_sleep(); \ |
8922915b | 381 | if (!___wait_cond_timeout(condition)) \ |
35a2af94 | 382 | __ret = __wait_event_timeout(wq, condition, timeout); \ |
1da177e4 LT |
383 | __ret; \ |
384 | }) | |
385 | ||
36df04bc PZ |
386 | #define __wait_event_freezable_timeout(wq, condition, timeout) \ |
387 | ___wait_event(wq, ___wait_cond_timeout(condition), \ | |
388 | TASK_INTERRUPTIBLE, 0, timeout, \ | |
389 | __ret = schedule_timeout(__ret); try_to_freeze()) | |
390 | ||
391 | /* | |
392 | * like wait_event_timeout() -- except it uses TASK_INTERRUPTIBLE to avoid | |
393 | * increasing load and is freezable. | |
394 | */ | |
395 | #define wait_event_freezable_timeout(wq, condition, timeout) \ | |
396 | ({ \ | |
397 | long __ret = timeout; \ | |
398 | might_sleep(); \ | |
399 | if (!___wait_cond_timeout(condition)) \ | |
400 | __ret = __wait_event_freezable_timeout(wq, condition, timeout); \ | |
401 | __ret; \ | |
402 | }) | |
403 | ||
9f3520c3 YL |
404 | #define __wait_event_exclusive_cmd(wq, condition, cmd1, cmd2) \ |
405 | (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 1, 0, \ | |
406 | cmd1; schedule(); cmd2) | |
407 | /* | |
408 | * Just like wait_event_cmd(), except it sets exclusive flag | |
409 | */ | |
410 | #define wait_event_exclusive_cmd(wq, condition, cmd1, cmd2) \ | |
411 | do { \ | |
412 | if (condition) \ | |
413 | break; \ | |
414 | __wait_event_exclusive_cmd(wq, condition, cmd1, cmd2); \ | |
415 | } while (0) | |
416 | ||
82e06c81 SL |
417 | #define __wait_event_cmd(wq, condition, cmd1, cmd2) \ |
418 | (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ | |
419 | cmd1; schedule(); cmd2) | |
420 | ||
421 | /** | |
422 | * wait_event_cmd - sleep until a condition gets true | |
423 | * @wq: the waitqueue to wait on | |
424 | * @condition: a C expression for the event to wait for | |
f434f7af MI |
425 | * @cmd1: the command will be executed before sleep |
426 | * @cmd2: the command will be executed after sleep | |
82e06c81 SL |
427 | * |
428 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
429 | * @condition evaluates to true. The @condition is checked each time | |
430 | * the waitqueue @wq is woken up. | |
431 | * | |
432 | * wake_up() has to be called after changing any variable that could | |
433 | * change the result of the wait condition. | |
434 | */ | |
435 | #define wait_event_cmd(wq, condition, cmd1, cmd2) \ | |
436 | do { \ | |
437 | if (condition) \ | |
438 | break; \ | |
439 | __wait_event_cmd(wq, condition, cmd1, cmd2); \ | |
440 | } while (0) | |
441 | ||
35a2af94 PZ |
442 | #define __wait_event_interruptible(wq, condition) \ |
443 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ | |
f13f4c41 | 444 | schedule()) |
1da177e4 LT |
445 | |
446 | /** | |
447 | * wait_event_interruptible - sleep until a condition gets true | |
448 | * @wq: the waitqueue to wait on | |
449 | * @condition: a C expression for the event to wait for | |
450 | * | |
451 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
452 | * @condition evaluates to true or a signal is received. | |
453 | * The @condition is checked each time the waitqueue @wq is woken up. | |
454 | * | |
455 | * wake_up() has to be called after changing any variable that could | |
456 | * change the result of the wait condition. | |
457 | * | |
458 | * The function will return -ERESTARTSYS if it was interrupted by a | |
459 | * signal and 0 if @condition evaluated to true. | |
460 | */ | |
461 | #define wait_event_interruptible(wq, condition) \ | |
462 | ({ \ | |
463 | int __ret = 0; \ | |
e22b886a | 464 | might_sleep(); \ |
1da177e4 | 465 | if (!(condition)) \ |
35a2af94 | 466 | __ret = __wait_event_interruptible(wq, condition); \ |
1da177e4 LT |
467 | __ret; \ |
468 | }) | |
469 | ||
35a2af94 PZ |
470 | #define __wait_event_interruptible_timeout(wq, condition, timeout) \ |
471 | ___wait_event(wq, ___wait_cond_timeout(condition), \ | |
472 | TASK_INTERRUPTIBLE, 0, timeout, \ | |
473 | __ret = schedule_timeout(__ret)) | |
1da177e4 LT |
474 | |
475 | /** | |
476 | * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses | |
477 | * @wq: the waitqueue to wait on | |
478 | * @condition: a C expression for the event to wait for | |
479 | * @timeout: timeout, in jiffies | |
480 | * | |
481 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
482 | * @condition evaluates to true or a signal is received. | |
483 | * The @condition is checked each time the waitqueue @wq is woken up. | |
484 | * | |
485 | * wake_up() has to be called after changing any variable that could | |
486 | * change the result of the wait condition. | |
487 | * | |
4c663cfc | 488 | * Returns: |
6b44f519 SD |
489 | * 0 if the @condition evaluated to %false after the @timeout elapsed, |
490 | * 1 if the @condition evaluated to %true after the @timeout elapsed, | |
491 | * the remaining jiffies (at least 1) if the @condition evaluated | |
492 | * to %true before the @timeout elapsed, or -%ERESTARTSYS if it was | |
493 | * interrupted by a signal. | |
1da177e4 LT |
494 | */ |
495 | #define wait_event_interruptible_timeout(wq, condition, timeout) \ | |
496 | ({ \ | |
497 | long __ret = timeout; \ | |
e22b886a | 498 | might_sleep(); \ |
8922915b | 499 | if (!___wait_cond_timeout(condition)) \ |
fb869b6e | 500 | __ret = __wait_event_interruptible_timeout(wq, \ |
35a2af94 | 501 | condition, timeout); \ |
1da177e4 LT |
502 | __ret; \ |
503 | }) | |
504 | ||
774a08b3 KO |
505 | #define __wait_event_hrtimeout(wq, condition, timeout, state) \ |
506 | ({ \ | |
507 | int __ret = 0; \ | |
774a08b3 KO |
508 | struct hrtimer_sleeper __t; \ |
509 | \ | |
510 | hrtimer_init_on_stack(&__t.timer, CLOCK_MONOTONIC, \ | |
511 | HRTIMER_MODE_REL); \ | |
512 | hrtimer_init_sleeper(&__t, current); \ | |
2456e855 | 513 | if ((timeout) != KTIME_MAX) \ |
774a08b3 KO |
514 | hrtimer_start_range_ns(&__t.timer, timeout, \ |
515 | current->timer_slack_ns, \ | |
516 | HRTIMER_MODE_REL); \ | |
517 | \ | |
35a2af94 | 518 | __ret = ___wait_event(wq, condition, state, 0, 0, \ |
774a08b3 KO |
519 | if (!__t.task) { \ |
520 | __ret = -ETIME; \ | |
521 | break; \ | |
522 | } \ | |
ebdc195f | 523 | schedule()); \ |
774a08b3 KO |
524 | \ |
525 | hrtimer_cancel(&__t.timer); \ | |
526 | destroy_hrtimer_on_stack(&__t.timer); \ | |
774a08b3 KO |
527 | __ret; \ |
528 | }) | |
529 | ||
530 | /** | |
531 | * wait_event_hrtimeout - sleep until a condition gets true or a timeout elapses | |
532 | * @wq: the waitqueue to wait on | |
533 | * @condition: a C expression for the event to wait for | |
534 | * @timeout: timeout, as a ktime_t | |
535 | * | |
536 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
537 | * @condition evaluates to true or a signal is received. | |
538 | * The @condition is checked each time the waitqueue @wq is woken up. | |
539 | * | |
540 | * wake_up() has to be called after changing any variable that could | |
541 | * change the result of the wait condition. | |
542 | * | |
543 | * The function returns 0 if @condition became true, or -ETIME if the timeout | |
544 | * elapsed. | |
545 | */ | |
546 | #define wait_event_hrtimeout(wq, condition, timeout) \ | |
547 | ({ \ | |
548 | int __ret = 0; \ | |
e22b886a | 549 | might_sleep(); \ |
774a08b3 KO |
550 | if (!(condition)) \ |
551 | __ret = __wait_event_hrtimeout(wq, condition, timeout, \ | |
552 | TASK_UNINTERRUPTIBLE); \ | |
553 | __ret; \ | |
554 | }) | |
555 | ||
556 | /** | |
557 | * wait_event_interruptible_hrtimeout - sleep until a condition gets true or a timeout elapses | |
558 | * @wq: the waitqueue to wait on | |
559 | * @condition: a C expression for the event to wait for | |
560 | * @timeout: timeout, as a ktime_t | |
561 | * | |
562 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
563 | * @condition evaluates to true or a signal is received. | |
564 | * The @condition is checked each time the waitqueue @wq is woken up. | |
565 | * | |
566 | * wake_up() has to be called after changing any variable that could | |
567 | * change the result of the wait condition. | |
568 | * | |
569 | * The function returns 0 if @condition became true, -ERESTARTSYS if it was | |
570 | * interrupted by a signal, or -ETIME if the timeout elapsed. | |
571 | */ | |
572 | #define wait_event_interruptible_hrtimeout(wq, condition, timeout) \ | |
573 | ({ \ | |
574 | long __ret = 0; \ | |
e22b886a | 575 | might_sleep(); \ |
774a08b3 KO |
576 | if (!(condition)) \ |
577 | __ret = __wait_event_hrtimeout(wq, condition, timeout, \ | |
578 | TASK_INTERRUPTIBLE); \ | |
579 | __ret; \ | |
580 | }) | |
581 | ||
35a2af94 PZ |
582 | #define __wait_event_interruptible_exclusive(wq, condition) \ |
583 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \ | |
48c25217 | 584 | schedule()) |
1da177e4 LT |
585 | |
586 | #define wait_event_interruptible_exclusive(wq, condition) \ | |
587 | ({ \ | |
588 | int __ret = 0; \ | |
e22b886a | 589 | might_sleep(); \ |
1da177e4 | 590 | if (!(condition)) \ |
35a2af94 | 591 | __ret = __wait_event_interruptible_exclusive(wq, condition);\ |
1da177e4 LT |
592 | __ret; \ |
593 | }) | |
594 | ||
6a0fb306 AV |
595 | #define __wait_event_killable_exclusive(wq, condition) \ |
596 | ___wait_event(wq, condition, TASK_KILLABLE, 1, 0, \ | |
597 | schedule()) | |
598 | ||
599 | #define wait_event_killable_exclusive(wq, condition) \ | |
600 | ({ \ | |
601 | int __ret = 0; \ | |
602 | might_sleep(); \ | |
603 | if (!(condition)) \ | |
604 | __ret = __wait_event_killable_exclusive(wq, condition); \ | |
605 | __ret; \ | |
606 | }) | |
607 | ||
22c43c81 | 608 | |
36df04bc PZ |
609 | #define __wait_event_freezable_exclusive(wq, condition) \ |
610 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \ | |
611 | schedule(); try_to_freeze()) | |
612 | ||
613 | #define wait_event_freezable_exclusive(wq, condition) \ | |
614 | ({ \ | |
615 | int __ret = 0; \ | |
616 | might_sleep(); \ | |
617 | if (!(condition)) \ | |
618 | __ret = __wait_event_freezable_exclusive(wq, condition);\ | |
619 | __ret; \ | |
620 | }) | |
621 | ||
622 | ||
22c43c81 MN |
623 | #define __wait_event_interruptible_locked(wq, condition, exclusive, irq) \ |
624 | ({ \ | |
625 | int __ret = 0; \ | |
626 | DEFINE_WAIT(__wait); \ | |
627 | if (exclusive) \ | |
628 | __wait.flags |= WQ_FLAG_EXCLUSIVE; \ | |
629 | do { \ | |
630 | if (likely(list_empty(&__wait.task_list))) \ | |
631 | __add_wait_queue_tail(&(wq), &__wait); \ | |
632 | set_current_state(TASK_INTERRUPTIBLE); \ | |
633 | if (signal_pending(current)) { \ | |
634 | __ret = -ERESTARTSYS; \ | |
635 | break; \ | |
636 | } \ | |
637 | if (irq) \ | |
638 | spin_unlock_irq(&(wq).lock); \ | |
639 | else \ | |
640 | spin_unlock(&(wq).lock); \ | |
641 | schedule(); \ | |
642 | if (irq) \ | |
643 | spin_lock_irq(&(wq).lock); \ | |
644 | else \ | |
645 | spin_lock(&(wq).lock); \ | |
646 | } while (!(condition)); \ | |
647 | __remove_wait_queue(&(wq), &__wait); \ | |
648 | __set_current_state(TASK_RUNNING); \ | |
649 | __ret; \ | |
650 | }) | |
651 | ||
652 | ||
653 | /** | |
654 | * wait_event_interruptible_locked - sleep until a condition gets true | |
655 | * @wq: the waitqueue to wait on | |
656 | * @condition: a C expression for the event to wait for | |
657 | * | |
658 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
659 | * @condition evaluates to true or a signal is received. | |
660 | * The @condition is checked each time the waitqueue @wq is woken up. | |
661 | * | |
662 | * It must be called with wq.lock being held. This spinlock is | |
663 | * unlocked while sleeping but @condition testing is done while lock | |
664 | * is held and when this macro exits the lock is held. | |
665 | * | |
666 | * The lock is locked/unlocked using spin_lock()/spin_unlock() | |
667 | * functions which must match the way they are locked/unlocked outside | |
668 | * of this macro. | |
669 | * | |
670 | * wake_up_locked() has to be called after changing any variable that could | |
671 | * change the result of the wait condition. | |
672 | * | |
673 | * The function will return -ERESTARTSYS if it was interrupted by a | |
674 | * signal and 0 if @condition evaluated to true. | |
675 | */ | |
676 | #define wait_event_interruptible_locked(wq, condition) \ | |
677 | ((condition) \ | |
678 | ? 0 : __wait_event_interruptible_locked(wq, condition, 0, 0)) | |
679 | ||
680 | /** | |
681 | * wait_event_interruptible_locked_irq - sleep until a condition gets true | |
682 | * @wq: the waitqueue to wait on | |
683 | * @condition: a C expression for the event to wait for | |
684 | * | |
685 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
686 | * @condition evaluates to true or a signal is received. | |
687 | * The @condition is checked each time the waitqueue @wq is woken up. | |
688 | * | |
689 | * It must be called with wq.lock being held. This spinlock is | |
690 | * unlocked while sleeping but @condition testing is done while lock | |
691 | * is held and when this macro exits the lock is held. | |
692 | * | |
693 | * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq() | |
694 | * functions which must match the way they are locked/unlocked outside | |
695 | * of this macro. | |
696 | * | |
697 | * wake_up_locked() has to be called after changing any variable that could | |
698 | * change the result of the wait condition. | |
699 | * | |
700 | * The function will return -ERESTARTSYS if it was interrupted by a | |
701 | * signal and 0 if @condition evaluated to true. | |
702 | */ | |
703 | #define wait_event_interruptible_locked_irq(wq, condition) \ | |
704 | ((condition) \ | |
705 | ? 0 : __wait_event_interruptible_locked(wq, condition, 0, 1)) | |
706 | ||
707 | /** | |
708 | * wait_event_interruptible_exclusive_locked - sleep exclusively until a condition gets true | |
709 | * @wq: the waitqueue to wait on | |
710 | * @condition: a C expression for the event to wait for | |
711 | * | |
712 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
713 | * @condition evaluates to true or a signal is received. | |
714 | * The @condition is checked each time the waitqueue @wq is woken up. | |
715 | * | |
716 | * It must be called with wq.lock being held. This spinlock is | |
717 | * unlocked while sleeping but @condition testing is done while lock | |
718 | * is held and when this macro exits the lock is held. | |
719 | * | |
720 | * The lock is locked/unlocked using spin_lock()/spin_unlock() | |
721 | * functions which must match the way they are locked/unlocked outside | |
722 | * of this macro. | |
723 | * | |
724 | * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag | |
725 | * set thus when other process waits process on the list if this | |
726 | * process is awaken further processes are not considered. | |
727 | * | |
728 | * wake_up_locked() has to be called after changing any variable that could | |
729 | * change the result of the wait condition. | |
730 | * | |
731 | * The function will return -ERESTARTSYS if it was interrupted by a | |
732 | * signal and 0 if @condition evaluated to true. | |
733 | */ | |
734 | #define wait_event_interruptible_exclusive_locked(wq, condition) \ | |
735 | ((condition) \ | |
736 | ? 0 : __wait_event_interruptible_locked(wq, condition, 1, 0)) | |
737 | ||
738 | /** | |
739 | * wait_event_interruptible_exclusive_locked_irq - sleep until a condition gets true | |
740 | * @wq: the waitqueue to wait on | |
741 | * @condition: a C expression for the event to wait for | |
742 | * | |
743 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
744 | * @condition evaluates to true or a signal is received. | |
745 | * The @condition is checked each time the waitqueue @wq is woken up. | |
746 | * | |
747 | * It must be called with wq.lock being held. This spinlock is | |
748 | * unlocked while sleeping but @condition testing is done while lock | |
749 | * is held and when this macro exits the lock is held. | |
750 | * | |
751 | * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq() | |
752 | * functions which must match the way they are locked/unlocked outside | |
753 | * of this macro. | |
754 | * | |
755 | * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag | |
756 | * set thus when other process waits process on the list if this | |
757 | * process is awaken further processes are not considered. | |
758 | * | |
759 | * wake_up_locked() has to be called after changing any variable that could | |
760 | * change the result of the wait condition. | |
761 | * | |
762 | * The function will return -ERESTARTSYS if it was interrupted by a | |
763 | * signal and 0 if @condition evaluated to true. | |
764 | */ | |
765 | #define wait_event_interruptible_exclusive_locked_irq(wq, condition) \ | |
766 | ((condition) \ | |
767 | ? 0 : __wait_event_interruptible_locked(wq, condition, 1, 1)) | |
768 | ||
769 | ||
35a2af94 PZ |
770 | #define __wait_event_killable(wq, condition) \ |
771 | ___wait_event(wq, condition, TASK_KILLABLE, 0, 0, schedule()) | |
1411d5a7 MW |
772 | |
773 | /** | |
774 | * wait_event_killable - sleep until a condition gets true | |
775 | * @wq: the waitqueue to wait on | |
776 | * @condition: a C expression for the event to wait for | |
777 | * | |
778 | * The process is put to sleep (TASK_KILLABLE) until the | |
779 | * @condition evaluates to true or a signal is received. | |
780 | * The @condition is checked each time the waitqueue @wq is woken up. | |
781 | * | |
782 | * wake_up() has to be called after changing any variable that could | |
783 | * change the result of the wait condition. | |
784 | * | |
785 | * The function will return -ERESTARTSYS if it was interrupted by a | |
786 | * signal and 0 if @condition evaluated to true. | |
787 | */ | |
788 | #define wait_event_killable(wq, condition) \ | |
789 | ({ \ | |
790 | int __ret = 0; \ | |
e22b886a | 791 | might_sleep(); \ |
1411d5a7 | 792 | if (!(condition)) \ |
35a2af94 | 793 | __ret = __wait_event_killable(wq, condition); \ |
1411d5a7 MW |
794 | __ret; \ |
795 | }) | |
796 | ||
eed8c02e LC |
797 | |
798 | #define __wait_event_lock_irq(wq, condition, lock, cmd) \ | |
35a2af94 PZ |
799 | (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ |
800 | spin_unlock_irq(&lock); \ | |
801 | cmd; \ | |
802 | schedule(); \ | |
803 | spin_lock_irq(&lock)) | |
eed8c02e LC |
804 | |
805 | /** | |
806 | * wait_event_lock_irq_cmd - sleep until a condition gets true. The | |
807 | * condition is checked under the lock. This | |
808 | * is expected to be called with the lock | |
809 | * taken. | |
810 | * @wq: the waitqueue to wait on | |
811 | * @condition: a C expression for the event to wait for | |
812 | * @lock: a locked spinlock_t, which will be released before cmd | |
813 | * and schedule() and reacquired afterwards. | |
814 | * @cmd: a command which is invoked outside the critical section before | |
815 | * sleep | |
816 | * | |
817 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
818 | * @condition evaluates to true. The @condition is checked each time | |
819 | * the waitqueue @wq is woken up. | |
820 | * | |
821 | * wake_up() has to be called after changing any variable that could | |
822 | * change the result of the wait condition. | |
823 | * | |
824 | * This is supposed to be called while holding the lock. The lock is | |
825 | * dropped before invoking the cmd and going to sleep and is reacquired | |
826 | * afterwards. | |
827 | */ | |
828 | #define wait_event_lock_irq_cmd(wq, condition, lock, cmd) \ | |
829 | do { \ | |
830 | if (condition) \ | |
831 | break; \ | |
832 | __wait_event_lock_irq(wq, condition, lock, cmd); \ | |
833 | } while (0) | |
834 | ||
835 | /** | |
836 | * wait_event_lock_irq - sleep until a condition gets true. The | |
837 | * condition is checked under the lock. This | |
838 | * is expected to be called with the lock | |
839 | * taken. | |
840 | * @wq: the waitqueue to wait on | |
841 | * @condition: a C expression for the event to wait for | |
842 | * @lock: a locked spinlock_t, which will be released before schedule() | |
843 | * and reacquired afterwards. | |
844 | * | |
845 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
846 | * @condition evaluates to true. The @condition is checked each time | |
847 | * the waitqueue @wq is woken up. | |
848 | * | |
849 | * wake_up() has to be called after changing any variable that could | |
850 | * change the result of the wait condition. | |
851 | * | |
852 | * This is supposed to be called while holding the lock. The lock is | |
853 | * dropped before going to sleep and is reacquired afterwards. | |
854 | */ | |
855 | #define wait_event_lock_irq(wq, condition, lock) \ | |
856 | do { \ | |
857 | if (condition) \ | |
858 | break; \ | |
859 | __wait_event_lock_irq(wq, condition, lock, ); \ | |
860 | } while (0) | |
861 | ||
862 | ||
35a2af94 | 863 | #define __wait_event_interruptible_lock_irq(wq, condition, lock, cmd) \ |
fb869b6e | 864 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ |
35a2af94 PZ |
865 | spin_unlock_irq(&lock); \ |
866 | cmd; \ | |
867 | schedule(); \ | |
8fbd88fa | 868 | spin_lock_irq(&lock)) |
eed8c02e LC |
869 | |
870 | /** | |
871 | * wait_event_interruptible_lock_irq_cmd - sleep until a condition gets true. | |
872 | * The condition is checked under the lock. This is expected to | |
873 | * be called with the lock taken. | |
874 | * @wq: the waitqueue to wait on | |
875 | * @condition: a C expression for the event to wait for | |
876 | * @lock: a locked spinlock_t, which will be released before cmd and | |
877 | * schedule() and reacquired afterwards. | |
878 | * @cmd: a command which is invoked outside the critical section before | |
879 | * sleep | |
880 | * | |
881 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
882 | * @condition evaluates to true or a signal is received. The @condition is | |
883 | * checked each time the waitqueue @wq is woken up. | |
884 | * | |
885 | * wake_up() has to be called after changing any variable that could | |
886 | * change the result of the wait condition. | |
887 | * | |
888 | * This is supposed to be called while holding the lock. The lock is | |
889 | * dropped before invoking the cmd and going to sleep and is reacquired | |
890 | * afterwards. | |
891 | * | |
892 | * The macro will return -ERESTARTSYS if it was interrupted by a signal | |
893 | * and 0 if @condition evaluated to true. | |
894 | */ | |
895 | #define wait_event_interruptible_lock_irq_cmd(wq, condition, lock, cmd) \ | |
896 | ({ \ | |
897 | int __ret = 0; \ | |
eed8c02e | 898 | if (!(condition)) \ |
fb869b6e | 899 | __ret = __wait_event_interruptible_lock_irq(wq, \ |
35a2af94 | 900 | condition, lock, cmd); \ |
eed8c02e LC |
901 | __ret; \ |
902 | }) | |
903 | ||
904 | /** | |
905 | * wait_event_interruptible_lock_irq - sleep until a condition gets true. | |
906 | * The condition is checked under the lock. This is expected | |
907 | * to be called with the lock taken. | |
908 | * @wq: the waitqueue to wait on | |
909 | * @condition: a C expression for the event to wait for | |
910 | * @lock: a locked spinlock_t, which will be released before schedule() | |
911 | * and reacquired afterwards. | |
912 | * | |
913 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
914 | * @condition evaluates to true or signal is received. The @condition is | |
915 | * checked each time the waitqueue @wq is woken up. | |
916 | * | |
917 | * wake_up() has to be called after changing any variable that could | |
918 | * change the result of the wait condition. | |
919 | * | |
920 | * This is supposed to be called while holding the lock. The lock is | |
921 | * dropped before going to sleep and is reacquired afterwards. | |
922 | * | |
923 | * The macro will return -ERESTARTSYS if it was interrupted by a signal | |
924 | * and 0 if @condition evaluated to true. | |
925 | */ | |
926 | #define wait_event_interruptible_lock_irq(wq, condition, lock) \ | |
927 | ({ \ | |
928 | int __ret = 0; \ | |
eed8c02e | 929 | if (!(condition)) \ |
35a2af94 | 930 | __ret = __wait_event_interruptible_lock_irq(wq, \ |
92ec1180 | 931 | condition, lock,); \ |
eed8c02e LC |
932 | __ret; \ |
933 | }) | |
934 | ||
fb869b6e IM |
935 | #define __wait_event_interruptible_lock_irq_timeout(wq, condition, \ |
936 | lock, timeout) \ | |
35a2af94 | 937 | ___wait_event(wq, ___wait_cond_timeout(condition), \ |
7d716456 | 938 | TASK_INTERRUPTIBLE, 0, timeout, \ |
35a2af94 PZ |
939 | spin_unlock_irq(&lock); \ |
940 | __ret = schedule_timeout(__ret); \ | |
a1dc6852 | 941 | spin_lock_irq(&lock)); |
d79ff142 MP |
942 | |
943 | /** | |
fb869b6e IM |
944 | * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets |
945 | * true or a timeout elapses. The condition is checked under | |
946 | * the lock. This is expected to be called with the lock taken. | |
d79ff142 MP |
947 | * @wq: the waitqueue to wait on |
948 | * @condition: a C expression for the event to wait for | |
949 | * @lock: a locked spinlock_t, which will be released before schedule() | |
950 | * and reacquired afterwards. | |
951 | * @timeout: timeout, in jiffies | |
952 | * | |
953 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
954 | * @condition evaluates to true or signal is received. The @condition is | |
955 | * checked each time the waitqueue @wq is woken up. | |
956 | * | |
957 | * wake_up() has to be called after changing any variable that could | |
958 | * change the result of the wait condition. | |
959 | * | |
960 | * This is supposed to be called while holding the lock. The lock is | |
961 | * dropped before going to sleep and is reacquired afterwards. | |
962 | * | |
963 | * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it | |
964 | * was interrupted by a signal, and the remaining jiffies otherwise | |
965 | * if the condition evaluated to true before the timeout elapsed. | |
966 | */ | |
967 | #define wait_event_interruptible_lock_irq_timeout(wq, condition, lock, \ | |
968 | timeout) \ | |
969 | ({ \ | |
35a2af94 | 970 | long __ret = timeout; \ |
8922915b | 971 | if (!___wait_cond_timeout(condition)) \ |
35a2af94 PZ |
972 | __ret = __wait_event_interruptible_lock_irq_timeout( \ |
973 | wq, condition, lock, timeout); \ | |
d79ff142 MP |
974 | __ret; \ |
975 | }) | |
976 | ||
1da177e4 LT |
977 | /* |
978 | * Waitqueues which are removed from the waitqueue_head at wakeup time | |
979 | */ | |
b3c97528 HH |
980 | void prepare_to_wait(wait_queue_head_t *q, wait_queue_t *wait, int state); |
981 | void prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state); | |
c2d81644 | 982 | long prepare_to_wait_event(wait_queue_head_t *q, wait_queue_t *wait, int state); |
b3c97528 | 983 | void finish_wait(wait_queue_head_t *q, wait_queue_t *wait); |
61ada528 PZ |
984 | long wait_woken(wait_queue_t *wait, unsigned mode, long timeout); |
985 | int woken_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key); | |
1da177e4 LT |
986 | int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key); |
987 | int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key); | |
988 | ||
bf368e4e | 989 | #define DEFINE_WAIT_FUNC(name, function) \ |
1da177e4 | 990 | wait_queue_t name = { \ |
c43dc2fd | 991 | .private = current, \ |
bf368e4e | 992 | .func = function, \ |
7e43c84e | 993 | .task_list = LIST_HEAD_INIT((name).task_list), \ |
1da177e4 LT |
994 | } |
995 | ||
bf368e4e ED |
996 | #define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function) |
997 | ||
1da177e4 LT |
998 | #define DEFINE_WAIT_BIT(name, word, bit) \ |
999 | struct wait_bit_queue name = { \ | |
1000 | .key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \ | |
1001 | .wait = { \ | |
c43dc2fd | 1002 | .private = current, \ |
1da177e4 LT |
1003 | .func = wake_bit_function, \ |
1004 | .task_list = \ | |
1005 | LIST_HEAD_INIT((name).wait.task_list), \ | |
1006 | }, \ | |
1007 | } | |
1008 | ||
1009 | #define init_wait(wait) \ | |
1010 | do { \ | |
c43dc2fd | 1011 | (wait)->private = current; \ |
1da177e4 LT |
1012 | (wait)->func = autoremove_wake_function; \ |
1013 | INIT_LIST_HEAD(&(wait)->task_list); \ | |
231d0aef | 1014 | (wait)->flags = 0; \ |
1da177e4 LT |
1015 | } while (0) |
1016 | ||
74316201 | 1017 | |
dfd01f02 PZ |
1018 | extern int bit_wait(struct wait_bit_key *, int); |
1019 | extern int bit_wait_io(struct wait_bit_key *, int); | |
1020 | extern int bit_wait_timeout(struct wait_bit_key *, int); | |
1021 | extern int bit_wait_io_timeout(struct wait_bit_key *, int); | |
74316201 | 1022 | |
1da177e4 LT |
1023 | /** |
1024 | * wait_on_bit - wait for a bit to be cleared | |
1025 | * @word: the word being waited on, a kernel virtual address | |
1026 | * @bit: the bit of the word being waited on | |
1da177e4 LT |
1027 | * @mode: the task state to sleep in |
1028 | * | |
1029 | * There is a standard hashed waitqueue table for generic use. This | |
1030 | * is the part of the hashtable's accessor API that waits on a bit. | |
1031 | * For instance, if one were to have waiters on a bitflag, one would | |
1032 | * call wait_on_bit() in threads waiting for the bit to clear. | |
1033 | * One uses wait_on_bit() where one is waiting for the bit to clear, | |
1034 | * but has no intention of setting it. | |
74316201 N |
1035 | * Returned value will be zero if the bit was cleared, or non-zero |
1036 | * if the process received a signal and the mode permitted wakeup | |
1037 | * on that signal. | |
1038 | */ | |
1039 | static inline int | |
7e605987 | 1040 | wait_on_bit(unsigned long *word, int bit, unsigned mode) |
74316201 | 1041 | { |
e22b886a | 1042 | might_sleep(); |
74316201 N |
1043 | if (!test_bit(bit, word)) |
1044 | return 0; | |
1045 | return out_of_line_wait_on_bit(word, bit, | |
1046 | bit_wait, | |
1047 | mode); | |
1048 | } | |
1049 | ||
1050 | /** | |
1051 | * wait_on_bit_io - wait for a bit to be cleared | |
1052 | * @word: the word being waited on, a kernel virtual address | |
1053 | * @bit: the bit of the word being waited on | |
1054 | * @mode: the task state to sleep in | |
1055 | * | |
1056 | * Use the standard hashed waitqueue table to wait for a bit | |
1057 | * to be cleared. This is similar to wait_on_bit(), but calls | |
1058 | * io_schedule() instead of schedule() for the actual waiting. | |
1059 | * | |
1060 | * Returned value will be zero if the bit was cleared, or non-zero | |
1061 | * if the process received a signal and the mode permitted wakeup | |
1062 | * on that signal. | |
1063 | */ | |
1064 | static inline int | |
7e605987 | 1065 | wait_on_bit_io(unsigned long *word, int bit, unsigned mode) |
74316201 | 1066 | { |
e22b886a | 1067 | might_sleep(); |
74316201 N |
1068 | if (!test_bit(bit, word)) |
1069 | return 0; | |
1070 | return out_of_line_wait_on_bit(word, bit, | |
1071 | bit_wait_io, | |
1072 | mode); | |
1073 | } | |
1074 | ||
44fc0e5e JH |
1075 | /** |
1076 | * wait_on_bit_timeout - wait for a bit to be cleared or a timeout elapses | |
1077 | * @word: the word being waited on, a kernel virtual address | |
1078 | * @bit: the bit of the word being waited on | |
1079 | * @mode: the task state to sleep in | |
1080 | * @timeout: timeout, in jiffies | |
1081 | * | |
1082 | * Use the standard hashed waitqueue table to wait for a bit | |
1083 | * to be cleared. This is similar to wait_on_bit(), except also takes a | |
1084 | * timeout parameter. | |
1085 | * | |
1086 | * Returned value will be zero if the bit was cleared before the | |
1087 | * @timeout elapsed, or non-zero if the @timeout elapsed or process | |
1088 | * received a signal and the mode permitted wakeup on that signal. | |
1089 | */ | |
1090 | static inline int | |
7e605987 PD |
1091 | wait_on_bit_timeout(unsigned long *word, int bit, unsigned mode, |
1092 | unsigned long timeout) | |
44fc0e5e JH |
1093 | { |
1094 | might_sleep(); | |
1095 | if (!test_bit(bit, word)) | |
1096 | return 0; | |
1097 | return out_of_line_wait_on_bit_timeout(word, bit, | |
1098 | bit_wait_timeout, | |
1099 | mode, timeout); | |
1100 | } | |
1101 | ||
74316201 N |
1102 | /** |
1103 | * wait_on_bit_action - wait for a bit to be cleared | |
1104 | * @word: the word being waited on, a kernel virtual address | |
1105 | * @bit: the bit of the word being waited on | |
1106 | * @action: the function used to sleep, which may take special actions | |
1107 | * @mode: the task state to sleep in | |
1108 | * | |
1109 | * Use the standard hashed waitqueue table to wait for a bit | |
1110 | * to be cleared, and allow the waiting action to be specified. | |
1111 | * This is like wait_on_bit() but allows fine control of how the waiting | |
1112 | * is done. | |
1113 | * | |
1114 | * Returned value will be zero if the bit was cleared, or non-zero | |
1115 | * if the process received a signal and the mode permitted wakeup | |
1116 | * on that signal. | |
1da177e4 | 1117 | */ |
fb869b6e | 1118 | static inline int |
7e605987 PD |
1119 | wait_on_bit_action(unsigned long *word, int bit, wait_bit_action_f *action, |
1120 | unsigned mode) | |
1da177e4 | 1121 | { |
e22b886a | 1122 | might_sleep(); |
1da177e4 LT |
1123 | if (!test_bit(bit, word)) |
1124 | return 0; | |
1125 | return out_of_line_wait_on_bit(word, bit, action, mode); | |
1126 | } | |
1127 | ||
1128 | /** | |
1129 | * wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it | |
1130 | * @word: the word being waited on, a kernel virtual address | |
1131 | * @bit: the bit of the word being waited on | |
1da177e4 LT |
1132 | * @mode: the task state to sleep in |
1133 | * | |
1134 | * There is a standard hashed waitqueue table for generic use. This | |
1135 | * is the part of the hashtable's accessor API that waits on a bit | |
1136 | * when one intends to set it, for instance, trying to lock bitflags. | |
1137 | * For instance, if one were to have waiters trying to set bitflag | |
1138 | * and waiting for it to clear before setting it, one would call | |
1139 | * wait_on_bit() in threads waiting to be able to set the bit. | |
1140 | * One uses wait_on_bit_lock() where one is waiting for the bit to | |
1141 | * clear with the intention of setting it, and when done, clearing it. | |
74316201 N |
1142 | * |
1143 | * Returns zero if the bit was (eventually) found to be clear and was | |
1144 | * set. Returns non-zero if a signal was delivered to the process and | |
1145 | * the @mode allows that signal to wake the process. | |
1146 | */ | |
1147 | static inline int | |
7e605987 | 1148 | wait_on_bit_lock(unsigned long *word, int bit, unsigned mode) |
74316201 | 1149 | { |
e22b886a | 1150 | might_sleep(); |
74316201 N |
1151 | if (!test_and_set_bit(bit, word)) |
1152 | return 0; | |
1153 | return out_of_line_wait_on_bit_lock(word, bit, bit_wait, mode); | |
1154 | } | |
1155 | ||
1156 | /** | |
1157 | * wait_on_bit_lock_io - wait for a bit to be cleared, when wanting to set it | |
1158 | * @word: the word being waited on, a kernel virtual address | |
1159 | * @bit: the bit of the word being waited on | |
1160 | * @mode: the task state to sleep in | |
1161 | * | |
1162 | * Use the standard hashed waitqueue table to wait for a bit | |
1163 | * to be cleared and then to atomically set it. This is similar | |
1164 | * to wait_on_bit(), but calls io_schedule() instead of schedule() | |
1165 | * for the actual waiting. | |
1166 | * | |
1167 | * Returns zero if the bit was (eventually) found to be clear and was | |
1168 | * set. Returns non-zero if a signal was delivered to the process and | |
1169 | * the @mode allows that signal to wake the process. | |
1170 | */ | |
1171 | static inline int | |
7e605987 | 1172 | wait_on_bit_lock_io(unsigned long *word, int bit, unsigned mode) |
74316201 | 1173 | { |
e22b886a | 1174 | might_sleep(); |
74316201 N |
1175 | if (!test_and_set_bit(bit, word)) |
1176 | return 0; | |
1177 | return out_of_line_wait_on_bit_lock(word, bit, bit_wait_io, mode); | |
1178 | } | |
1179 | ||
1180 | /** | |
1181 | * wait_on_bit_lock_action - wait for a bit to be cleared, when wanting to set it | |
1182 | * @word: the word being waited on, a kernel virtual address | |
1183 | * @bit: the bit of the word being waited on | |
1184 | * @action: the function used to sleep, which may take special actions | |
1185 | * @mode: the task state to sleep in | |
1186 | * | |
1187 | * Use the standard hashed waitqueue table to wait for a bit | |
1188 | * to be cleared and then to set it, and allow the waiting action | |
1189 | * to be specified. | |
1190 | * This is like wait_on_bit() but allows fine control of how the waiting | |
1191 | * is done. | |
1192 | * | |
1193 | * Returns zero if the bit was (eventually) found to be clear and was | |
1194 | * set. Returns non-zero if a signal was delivered to the process and | |
1195 | * the @mode allows that signal to wake the process. | |
1da177e4 | 1196 | */ |
fb869b6e | 1197 | static inline int |
7e605987 PD |
1198 | wait_on_bit_lock_action(unsigned long *word, int bit, wait_bit_action_f *action, |
1199 | unsigned mode) | |
1da177e4 | 1200 | { |
e22b886a | 1201 | might_sleep(); |
1da177e4 LT |
1202 | if (!test_and_set_bit(bit, word)) |
1203 | return 0; | |
1204 | return out_of_line_wait_on_bit_lock(word, bit, action, mode); | |
1205 | } | |
cb65537e DH |
1206 | |
1207 | /** | |
1208 | * wait_on_atomic_t - Wait for an atomic_t to become 0 | |
1209 | * @val: The atomic value being waited on, a kernel virtual address | |
1210 | * @action: the function used to sleep, which may take special actions | |
1211 | * @mode: the task state to sleep in | |
1212 | * | |
1213 | * Wait for an atomic_t to become 0. We abuse the bit-wait waitqueue table for | |
1214 | * the purpose of getting a waitqueue, but we set the key to a bit number | |
1215 | * outside of the target 'word'. | |
1216 | */ | |
1217 | static inline | |
1218 | int wait_on_atomic_t(atomic_t *val, int (*action)(atomic_t *), unsigned mode) | |
1219 | { | |
e22b886a | 1220 | might_sleep(); |
cb65537e DH |
1221 | if (atomic_read(val) == 0) |
1222 | return 0; | |
1223 | return out_of_line_wait_on_atomic_t(val, action, mode); | |
1224 | } | |
fb869b6e IM |
1225 | |
1226 | #endif /* _LINUX_WAIT_H */ |