Line data Source code
1 : /* SPDX-License-Identifier: GPL-2.0 */
2 : #ifndef _LINUX_WAIT_H
3 : #define _LINUX_WAIT_H
4 : /*
5 : * Linux wait queue related types and methods
6 : */
7 : #include <linux/list.h>
8 : #include <linux/stddef.h>
9 : #include <linux/spinlock.h>
10 :
11 : #include <asm/current.h>
12 : #include <uapi/linux/wait.h>
13 :
14 : typedef struct wait_queue_entry wait_queue_entry_t;
15 :
16 : typedef int (*wait_queue_func_t)(struct wait_queue_entry *wq_entry, unsigned mode, int flags, void *key);
17 : int default_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int flags, void *key);
18 :
19 : /* wait_queue_entry::flags */
20 : #define WQ_FLAG_EXCLUSIVE 0x01
21 : #define WQ_FLAG_WOKEN 0x02
22 : #define WQ_FLAG_BOOKMARK 0x04
23 : #define WQ_FLAG_CUSTOM 0x08
24 : #define WQ_FLAG_DONE 0x10
25 : #define WQ_FLAG_PRIORITY 0x20
26 :
27 : /*
28 : * A single wait-queue entry structure:
29 : */
30 : struct wait_queue_entry {
31 : unsigned int flags;
32 : void *private;
33 : wait_queue_func_t func;
34 : struct list_head entry;
35 : };
36 :
37 : struct wait_queue_head {
38 : spinlock_t lock;
39 : struct list_head head;
40 : };
41 : typedef struct wait_queue_head wait_queue_head_t;
42 :
43 : struct task_struct;
44 :
45 : /*
46 : * Macros for declaration and initialisaton of the datatypes
47 : */
48 :
49 : #define __WAITQUEUE_INITIALIZER(name, tsk) { \
50 : .private = tsk, \
51 : .func = default_wake_function, \
52 : .entry = { NULL, NULL } }
53 :
54 : #define DECLARE_WAITQUEUE(name, tsk) \
55 : struct wait_queue_entry name = __WAITQUEUE_INITIALIZER(name, tsk)
56 :
57 : #define __WAIT_QUEUE_HEAD_INITIALIZER(name) { \
58 : .lock = __SPIN_LOCK_UNLOCKED(name.lock), \
59 : .head = LIST_HEAD_INIT(name.head) }
60 :
61 : #define DECLARE_WAIT_QUEUE_HEAD(name) \
62 : struct wait_queue_head name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
63 :
64 : extern void __init_waitqueue_head(struct wait_queue_head *wq_head, const char *name, struct lock_class_key *);
65 :
66 : #define init_waitqueue_head(wq_head) \
67 : do { \
68 : static struct lock_class_key __key; \
69 : \
70 : __init_waitqueue_head((wq_head), #wq_head, &__key); \
71 : } while (0)
72 :
73 : #ifdef CONFIG_LOCKDEP
74 : # define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
75 : ({ init_waitqueue_head(&name); name; })
76 : # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \
77 : struct wait_queue_head name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
78 : #else
79 : # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name)
80 : #endif
81 :
82 : static inline void init_waitqueue_entry(struct wait_queue_entry *wq_entry, struct task_struct *p)
83 : {
84 0 : wq_entry->flags = 0;
85 0 : wq_entry->private = p;
86 0 : wq_entry->func = default_wake_function;
87 : }
88 :
89 : static inline void
90 : init_waitqueue_func_entry(struct wait_queue_entry *wq_entry, wait_queue_func_t func)
91 : {
92 0 : wq_entry->flags = 0;
93 0 : wq_entry->private = NULL;
94 0 : wq_entry->func = func;
95 : }
96 :
97 : /**
98 : * waitqueue_active -- locklessly test for waiters on the queue
99 : * @wq_head: the waitqueue to test for waiters
100 : *
101 : * returns true if the wait list is not empty
102 : *
103 : * NOTE: this function is lockless and requires care, incorrect usage _will_
104 : * lead to sporadic and non-obvious failure.
105 : *
106 : * Use either while holding wait_queue_head::lock or when used for wakeups
107 : * with an extra smp_mb() like::
108 : *
109 : * CPU0 - waker CPU1 - waiter
110 : *
111 : * for (;;) {
112 : * @cond = true; prepare_to_wait(&wq_head, &wait, state);
113 : * smp_mb(); // smp_mb() from set_current_state()
114 : * if (waitqueue_active(wq_head)) if (@cond)
115 : * wake_up(wq_head); break;
116 : * schedule();
117 : * }
118 : * finish_wait(&wq_head, &wait);
119 : *
120 : * Because without the explicit smp_mb() it's possible for the
121 : * waitqueue_active() load to get hoisted over the @cond store such that we'll
122 : * observe an empty wait list while the waiter might not observe @cond.
123 : *
124 : * Also note that this 'optimization' trades a spin_lock() for an smp_mb(),
125 : * which (when the lock is uncontended) are of roughly equal cost.
126 : */
127 : static inline int waitqueue_active(struct wait_queue_head *wq_head)
128 : {
129 740 : return !list_empty(&wq_head->head);
130 : }
131 :
132 : /**
133 : * wq_has_single_sleeper - check if there is only one sleeper
134 : * @wq_head: wait queue head
135 : *
136 : * Returns true of wq_head has only one sleeper on the list.
137 : *
138 : * Please refer to the comment for waitqueue_active.
139 : */
140 : static inline bool wq_has_single_sleeper(struct wait_queue_head *wq_head)
141 : {
142 : return list_is_singular(&wq_head->head);
143 : }
144 :
145 : /**
146 : * wq_has_sleeper - check if there are any waiting processes
147 : * @wq_head: wait queue head
148 : *
149 : * Returns true if wq_head has waiting processes
150 : *
151 : * Please refer to the comment for waitqueue_active.
152 : */
153 : static inline bool wq_has_sleeper(struct wait_queue_head *wq_head)
154 : {
155 : /*
156 : * We need to be sure we are in sync with the
157 : * add_wait_queue modifications to the wait queue.
158 : *
159 : * This memory barrier should be paired with one on the
160 : * waiting side.
161 : */
162 0 : smp_mb();
163 0 : return waitqueue_active(wq_head);
164 : }
165 :
166 : extern void add_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
167 : extern void add_wait_queue_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
168 : extern void add_wait_queue_priority(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
169 : extern void remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
170 :
171 : static inline void __add_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
172 : {
173 3 : struct list_head *head = &wq_head->head;
174 : struct wait_queue_entry *wq;
175 :
176 3 : list_for_each_entry(wq, &wq_head->head, entry) {
177 0 : if (!(wq->flags & WQ_FLAG_PRIORITY))
178 : break;
179 0 : head = &wq->entry;
180 : }
181 6 : list_add(&wq_entry->entry, head);
182 : }
183 :
184 : /*
185 : * Used for wake-one threads:
186 : */
187 : static inline void
188 : __add_wait_queue_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
189 : {
190 0 : wq_entry->flags |= WQ_FLAG_EXCLUSIVE;
191 0 : __add_wait_queue(wq_head, wq_entry);
192 : }
193 :
194 : static inline void __add_wait_queue_entry_tail(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
195 : {
196 0 : list_add_tail(&wq_entry->entry, &wq_head->head);
197 : }
198 :
199 : static inline void
200 : __add_wait_queue_entry_tail_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
201 : {
202 : wq_entry->flags |= WQ_FLAG_EXCLUSIVE;
203 : __add_wait_queue_entry_tail(wq_head, wq_entry);
204 : }
205 :
206 : static inline void
207 : __remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry)
208 : {
209 0 : list_del(&wq_entry->entry);
210 : }
211 :
212 : void __wake_up(struct wait_queue_head *wq_head, unsigned int mode, int nr, void *key);
213 : void __wake_up_locked_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
214 : void __wake_up_locked_key_bookmark(struct wait_queue_head *wq_head,
215 : unsigned int mode, void *key, wait_queue_entry_t *bookmark);
216 : void __wake_up_sync_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
217 : void __wake_up_locked_sync_key(struct wait_queue_head *wq_head, unsigned int mode, void *key);
218 : void __wake_up_locked(struct wait_queue_head *wq_head, unsigned int mode, int nr);
219 : void __wake_up_sync(struct wait_queue_head *wq_head, unsigned int mode);
220 : void __wake_up_pollfree(struct wait_queue_head *wq_head);
221 :
222 : #define wake_up(x) __wake_up(x, TASK_NORMAL, 1, NULL)
223 : #define wake_up_nr(x, nr) __wake_up(x, TASK_NORMAL, nr, NULL)
224 : #define wake_up_all(x) __wake_up(x, TASK_NORMAL, 0, NULL)
225 : #define wake_up_locked(x) __wake_up_locked((x), TASK_NORMAL, 1)
226 : #define wake_up_all_locked(x) __wake_up_locked((x), TASK_NORMAL, 0)
227 :
228 : #define wake_up_interruptible(x) __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
229 : #define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
230 : #define wake_up_interruptible_all(x) __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
231 : #define wake_up_interruptible_sync(x) __wake_up_sync((x), TASK_INTERRUPTIBLE)
232 :
233 : /*
234 : * Wakeup macros to be used to report events to the targets.
235 : */
236 : #define poll_to_key(m) ((void *)(__force uintptr_t)(__poll_t)(m))
237 : #define key_to_poll(m) ((__force __poll_t)(uintptr_t)(void *)(m))
238 : #define wake_up_poll(x, m) \
239 : __wake_up(x, TASK_NORMAL, 1, poll_to_key(m))
240 : #define wake_up_locked_poll(x, m) \
241 : __wake_up_locked_key((x), TASK_NORMAL, poll_to_key(m))
242 : #define wake_up_interruptible_poll(x, m) \
243 : __wake_up(x, TASK_INTERRUPTIBLE, 1, poll_to_key(m))
244 : #define wake_up_interruptible_sync_poll(x, m) \
245 : __wake_up_sync_key((x), TASK_INTERRUPTIBLE, poll_to_key(m))
246 : #define wake_up_interruptible_sync_poll_locked(x, m) \
247 : __wake_up_locked_sync_key((x), TASK_INTERRUPTIBLE, poll_to_key(m))
248 :
249 : /**
250 : * wake_up_pollfree - signal that a polled waitqueue is going away
251 : * @wq_head: the wait queue head
252 : *
253 : * In the very rare cases where a ->poll() implementation uses a waitqueue whose
254 : * lifetime is tied to a task rather than to the 'struct file' being polled,
255 : * this function must be called before the waitqueue is freed so that
256 : * non-blocking polls (e.g. epoll) are notified that the queue is going away.
257 : *
258 : * The caller must also RCU-delay the freeing of the wait_queue_head, e.g. via
259 : * an explicit synchronize_rcu() or call_rcu(), or via SLAB_TYPESAFE_BY_RCU.
260 : */
261 : static inline void wake_up_pollfree(struct wait_queue_head *wq_head)
262 : {
263 : /*
264 : * For performance reasons, we don't always take the queue lock here.
265 : * Therefore, we might race with someone removing the last entry from
266 : * the queue, and proceed while they still hold the queue lock.
267 : * However, rcu_read_lock() is required to be held in such cases, so we
268 : * can safely proceed with an RCU-delayed free.
269 : */
270 93 : if (waitqueue_active(wq_head))
271 0 : __wake_up_pollfree(wq_head);
272 : }
273 :
274 : #define ___wait_cond_timeout(condition) \
275 : ({ \
276 : bool __cond = (condition); \
277 : if (__cond && !__ret) \
278 : __ret = 1; \
279 : __cond || !__ret; \
280 : })
281 :
282 : #define ___wait_is_interruptible(state) \
283 : (!__builtin_constant_p(state) || \
284 : state == TASK_INTERRUPTIBLE || state == TASK_KILLABLE) \
285 :
286 : extern void init_wait_entry(struct wait_queue_entry *wq_entry, int flags);
287 :
288 : /*
289 : * The below macro ___wait_event() has an explicit shadow of the __ret
290 : * variable when used from the wait_event_*() macros.
291 : *
292 : * This is so that both can use the ___wait_cond_timeout() construct
293 : * to wrap the condition.
294 : *
295 : * The type inconsistency of the wait_event_*() __ret variable is also
296 : * on purpose; we use long where we can return timeout values and int
297 : * otherwise.
298 : */
299 :
300 : #define ___wait_event(wq_head, condition, state, exclusive, ret, cmd) \
301 : ({ \
302 : __label__ __out; \
303 : struct wait_queue_entry __wq_entry; \
304 : long __ret = ret; /* explicit shadow */ \
305 : \
306 : init_wait_entry(&__wq_entry, exclusive ? WQ_FLAG_EXCLUSIVE : 0); \
307 : for (;;) { \
308 : long __int = prepare_to_wait_event(&wq_head, &__wq_entry, state);\
309 : \
310 : if (condition) \
311 : break; \
312 : \
313 : if (___wait_is_interruptible(state) && __int) { \
314 : __ret = __int; \
315 : goto __out; \
316 : } \
317 : \
318 : cmd; \
319 : } \
320 : finish_wait(&wq_head, &__wq_entry); \
321 : __out: __ret; \
322 : })
323 :
324 : #define __wait_event(wq_head, condition) \
325 : (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0, \
326 : schedule())
327 :
328 : /**
329 : * wait_event - sleep until a condition gets true
330 : * @wq_head: the waitqueue to wait on
331 : * @condition: a C expression for the event to wait for
332 : *
333 : * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
334 : * @condition evaluates to true. The @condition is checked each time
335 : * the waitqueue @wq_head is woken up.
336 : *
337 : * wake_up() has to be called after changing any variable that could
338 : * change the result of the wait condition.
339 : */
340 : #define wait_event(wq_head, condition) \
341 : do { \
342 : might_sleep(); \
343 : if (condition) \
344 : break; \
345 : __wait_event(wq_head, condition); \
346 : } while (0)
347 :
348 : #define __io_wait_event(wq_head, condition) \
349 : (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0, \
350 : io_schedule())
351 :
352 : /*
353 : * io_wait_event() -- like wait_event() but with io_schedule()
354 : */
355 : #define io_wait_event(wq_head, condition) \
356 : do { \
357 : might_sleep(); \
358 : if (condition) \
359 : break; \
360 : __io_wait_event(wq_head, condition); \
361 : } while (0)
362 :
363 : #define __wait_event_freezable(wq_head, condition) \
364 : ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0, \
365 : freezable_schedule())
366 :
367 : /**
368 : * wait_event_freezable - sleep (or freeze) until a condition gets true
369 : * @wq_head: the waitqueue to wait on
370 : * @condition: a C expression for the event to wait for
371 : *
372 : * The process is put to sleep (TASK_INTERRUPTIBLE -- so as not to contribute
373 : * to system load) until the @condition evaluates to true. The
374 : * @condition is checked each time the waitqueue @wq_head is woken up.
375 : *
376 : * wake_up() has to be called after changing any variable that could
377 : * change the result of the wait condition.
378 : */
379 : #define wait_event_freezable(wq_head, condition) \
380 : ({ \
381 : int __ret = 0; \
382 : might_sleep(); \
383 : if (!(condition)) \
384 : __ret = __wait_event_freezable(wq_head, condition); \
385 : __ret; \
386 : })
387 :
388 : #define __wait_event_timeout(wq_head, condition, timeout) \
389 : ___wait_event(wq_head, ___wait_cond_timeout(condition), \
390 : TASK_UNINTERRUPTIBLE, 0, timeout, \
391 : __ret = schedule_timeout(__ret))
392 :
393 : /**
394 : * wait_event_timeout - sleep until a condition gets true or a timeout elapses
395 : * @wq_head: the waitqueue to wait on
396 : * @condition: a C expression for the event to wait for
397 : * @timeout: timeout, in jiffies
398 : *
399 : * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
400 : * @condition evaluates to true. The @condition is checked each time
401 : * the waitqueue @wq_head is woken up.
402 : *
403 : * wake_up() has to be called after changing any variable that could
404 : * change the result of the wait condition.
405 : *
406 : * Returns:
407 : * 0 if the @condition evaluated to %false after the @timeout elapsed,
408 : * 1 if the @condition evaluated to %true after the @timeout elapsed,
409 : * or the remaining jiffies (at least 1) if the @condition evaluated
410 : * to %true before the @timeout elapsed.
411 : */
412 : #define wait_event_timeout(wq_head, condition, timeout) \
413 : ({ \
414 : long __ret = timeout; \
415 : might_sleep(); \
416 : if (!___wait_cond_timeout(condition)) \
417 : __ret = __wait_event_timeout(wq_head, condition, timeout); \
418 : __ret; \
419 : })
420 :
421 : #define __wait_event_freezable_timeout(wq_head, condition, timeout) \
422 : ___wait_event(wq_head, ___wait_cond_timeout(condition), \
423 : TASK_INTERRUPTIBLE, 0, timeout, \
424 : __ret = freezable_schedule_timeout(__ret))
425 :
426 : /*
427 : * like wait_event_timeout() -- except it uses TASK_INTERRUPTIBLE to avoid
428 : * increasing load and is freezable.
429 : */
430 : #define wait_event_freezable_timeout(wq_head, condition, timeout) \
431 : ({ \
432 : long __ret = timeout; \
433 : might_sleep(); \
434 : if (!___wait_cond_timeout(condition)) \
435 : __ret = __wait_event_freezable_timeout(wq_head, condition, timeout); \
436 : __ret; \
437 : })
438 :
439 : #define __wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2) \
440 : (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 1, 0, \
441 : cmd1; schedule(); cmd2)
442 : /*
443 : * Just like wait_event_cmd(), except it sets exclusive flag
444 : */
445 : #define wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2) \
446 : do { \
447 : if (condition) \
448 : break; \
449 : __wait_event_exclusive_cmd(wq_head, condition, cmd1, cmd2); \
450 : } while (0)
451 :
452 : #define __wait_event_cmd(wq_head, condition, cmd1, cmd2) \
453 : (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0, \
454 : cmd1; schedule(); cmd2)
455 :
456 : /**
457 : * wait_event_cmd - sleep until a condition gets true
458 : * @wq_head: the waitqueue to wait on
459 : * @condition: a C expression for the event to wait for
460 : * @cmd1: the command will be executed before sleep
461 : * @cmd2: the command will be executed after sleep
462 : *
463 : * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
464 : * @condition evaluates to true. The @condition is checked each time
465 : * the waitqueue @wq_head is woken up.
466 : *
467 : * wake_up() has to be called after changing any variable that could
468 : * change the result of the wait condition.
469 : */
470 : #define wait_event_cmd(wq_head, condition, cmd1, cmd2) \
471 : do { \
472 : if (condition) \
473 : break; \
474 : __wait_event_cmd(wq_head, condition, cmd1, cmd2); \
475 : } while (0)
476 :
477 : #define __wait_event_interruptible(wq_head, condition) \
478 : ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0, \
479 : schedule())
480 :
481 : /**
482 : * wait_event_interruptible - sleep until a condition gets true
483 : * @wq_head: the waitqueue to wait on
484 : * @condition: a C expression for the event to wait for
485 : *
486 : * The process is put to sleep (TASK_INTERRUPTIBLE) until the
487 : * @condition evaluates to true or a signal is received.
488 : * The @condition is checked each time the waitqueue @wq_head is woken up.
489 : *
490 : * wake_up() has to be called after changing any variable that could
491 : * change the result of the wait condition.
492 : *
493 : * The function will return -ERESTARTSYS if it was interrupted by a
494 : * signal and 0 if @condition evaluated to true.
495 : */
496 : #define wait_event_interruptible(wq_head, condition) \
497 : ({ \
498 : int __ret = 0; \
499 : might_sleep(); \
500 : if (!(condition)) \
501 : __ret = __wait_event_interruptible(wq_head, condition); \
502 : __ret; \
503 : })
504 :
505 : #define __wait_event_interruptible_timeout(wq_head, condition, timeout) \
506 : ___wait_event(wq_head, ___wait_cond_timeout(condition), \
507 : TASK_INTERRUPTIBLE, 0, timeout, \
508 : __ret = schedule_timeout(__ret))
509 :
510 : /**
511 : * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
512 : * @wq_head: the waitqueue to wait on
513 : * @condition: a C expression for the event to wait for
514 : * @timeout: timeout, in jiffies
515 : *
516 : * The process is put to sleep (TASK_INTERRUPTIBLE) until the
517 : * @condition evaluates to true or a signal is received.
518 : * The @condition is checked each time the waitqueue @wq_head is woken up.
519 : *
520 : * wake_up() has to be called after changing any variable that could
521 : * change the result of the wait condition.
522 : *
523 : * Returns:
524 : * 0 if the @condition evaluated to %false after the @timeout elapsed,
525 : * 1 if the @condition evaluated to %true after the @timeout elapsed,
526 : * the remaining jiffies (at least 1) if the @condition evaluated
527 : * to %true before the @timeout elapsed, or -%ERESTARTSYS if it was
528 : * interrupted by a signal.
529 : */
530 : #define wait_event_interruptible_timeout(wq_head, condition, timeout) \
531 : ({ \
532 : long __ret = timeout; \
533 : might_sleep(); \
534 : if (!___wait_cond_timeout(condition)) \
535 : __ret = __wait_event_interruptible_timeout(wq_head, \
536 : condition, timeout); \
537 : __ret; \
538 : })
539 :
540 : #define __wait_event_hrtimeout(wq_head, condition, timeout, state) \
541 : ({ \
542 : int __ret = 0; \
543 : struct hrtimer_sleeper __t; \
544 : \
545 : hrtimer_init_sleeper_on_stack(&__t, CLOCK_MONOTONIC, \
546 : HRTIMER_MODE_REL); \
547 : if ((timeout) != KTIME_MAX) \
548 : hrtimer_start_range_ns(&__t.timer, timeout, \
549 : current->timer_slack_ns, \
550 : HRTIMER_MODE_REL); \
551 : \
552 : __ret = ___wait_event(wq_head, condition, state, 0, 0, \
553 : if (!__t.task) { \
554 : __ret = -ETIME; \
555 : break; \
556 : } \
557 : schedule()); \
558 : \
559 : hrtimer_cancel(&__t.timer); \
560 : destroy_hrtimer_on_stack(&__t.timer); \
561 : __ret; \
562 : })
563 :
564 : /**
565 : * wait_event_hrtimeout - sleep until a condition gets true or a timeout elapses
566 : * @wq_head: the waitqueue to wait on
567 : * @condition: a C expression for the event to wait for
568 : * @timeout: timeout, as a ktime_t
569 : *
570 : * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
571 : * @condition evaluates to true or a signal is received.
572 : * The @condition is checked each time the waitqueue @wq_head is woken up.
573 : *
574 : * wake_up() has to be called after changing any variable that could
575 : * change the result of the wait condition.
576 : *
577 : * The function returns 0 if @condition became true, or -ETIME if the timeout
578 : * elapsed.
579 : */
580 : #define wait_event_hrtimeout(wq_head, condition, timeout) \
581 : ({ \
582 : int __ret = 0; \
583 : might_sleep(); \
584 : if (!(condition)) \
585 : __ret = __wait_event_hrtimeout(wq_head, condition, timeout, \
586 : TASK_UNINTERRUPTIBLE); \
587 : __ret; \
588 : })
589 :
590 : /**
591 : * wait_event_interruptible_hrtimeout - sleep until a condition gets true or a timeout elapses
592 : * @wq: the waitqueue to wait on
593 : * @condition: a C expression for the event to wait for
594 : * @timeout: timeout, as a ktime_t
595 : *
596 : * The process is put to sleep (TASK_INTERRUPTIBLE) until the
597 : * @condition evaluates to true or a signal is received.
598 : * The @condition is checked each time the waitqueue @wq is woken up.
599 : *
600 : * wake_up() has to be called after changing any variable that could
601 : * change the result of the wait condition.
602 : *
603 : * The function returns 0 if @condition became true, -ERESTARTSYS if it was
604 : * interrupted by a signal, or -ETIME if the timeout elapsed.
605 : */
606 : #define wait_event_interruptible_hrtimeout(wq, condition, timeout) \
607 : ({ \
608 : long __ret = 0; \
609 : might_sleep(); \
610 : if (!(condition)) \
611 : __ret = __wait_event_hrtimeout(wq, condition, timeout, \
612 : TASK_INTERRUPTIBLE); \
613 : __ret; \
614 : })
615 :
616 : #define __wait_event_interruptible_exclusive(wq, condition) \
617 : ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \
618 : schedule())
619 :
620 : #define wait_event_interruptible_exclusive(wq, condition) \
621 : ({ \
622 : int __ret = 0; \
623 : might_sleep(); \
624 : if (!(condition)) \
625 : __ret = __wait_event_interruptible_exclusive(wq, condition); \
626 : __ret; \
627 : })
628 :
629 : #define __wait_event_killable_exclusive(wq, condition) \
630 : ___wait_event(wq, condition, TASK_KILLABLE, 1, 0, \
631 : schedule())
632 :
633 : #define wait_event_killable_exclusive(wq, condition) \
634 : ({ \
635 : int __ret = 0; \
636 : might_sleep(); \
637 : if (!(condition)) \
638 : __ret = __wait_event_killable_exclusive(wq, condition); \
639 : __ret; \
640 : })
641 :
642 :
643 : #define __wait_event_freezable_exclusive(wq, condition) \
644 : ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \
645 : freezable_schedule())
646 :
647 : #define wait_event_freezable_exclusive(wq, condition) \
648 : ({ \
649 : int __ret = 0; \
650 : might_sleep(); \
651 : if (!(condition)) \
652 : __ret = __wait_event_freezable_exclusive(wq, condition); \
653 : __ret; \
654 : })
655 :
656 : /**
657 : * wait_event_idle - wait for a condition without contributing to system load
658 : * @wq_head: the waitqueue to wait on
659 : * @condition: a C expression for the event to wait for
660 : *
661 : * The process is put to sleep (TASK_IDLE) until the
662 : * @condition evaluates to true.
663 : * The @condition is checked each time the waitqueue @wq_head is woken up.
664 : *
665 : * wake_up() has to be called after changing any variable that could
666 : * change the result of the wait condition.
667 : *
668 : */
669 : #define wait_event_idle(wq_head, condition) \
670 : do { \
671 : might_sleep(); \
672 : if (!(condition)) \
673 : ___wait_event(wq_head, condition, TASK_IDLE, 0, 0, schedule()); \
674 : } while (0)
675 :
676 : /**
677 : * wait_event_idle_exclusive - wait for a condition with contributing to system load
678 : * @wq_head: the waitqueue to wait on
679 : * @condition: a C expression for the event to wait for
680 : *
681 : * The process is put to sleep (TASK_IDLE) until the
682 : * @condition evaluates to true.
683 : * The @condition is checked each time the waitqueue @wq_head is woken up.
684 : *
685 : * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
686 : * set thus if other processes wait on the same list, when this
687 : * process is woken further processes are not considered.
688 : *
689 : * wake_up() has to be called after changing any variable that could
690 : * change the result of the wait condition.
691 : *
692 : */
693 : #define wait_event_idle_exclusive(wq_head, condition) \
694 : do { \
695 : might_sleep(); \
696 : if (!(condition)) \
697 : ___wait_event(wq_head, condition, TASK_IDLE, 1, 0, schedule()); \
698 : } while (0)
699 :
700 : #define __wait_event_idle_timeout(wq_head, condition, timeout) \
701 : ___wait_event(wq_head, ___wait_cond_timeout(condition), \
702 : TASK_IDLE, 0, timeout, \
703 : __ret = schedule_timeout(__ret))
704 :
705 : /**
706 : * wait_event_idle_timeout - sleep without load until a condition becomes true or a timeout elapses
707 : * @wq_head: the waitqueue to wait on
708 : * @condition: a C expression for the event to wait for
709 : * @timeout: timeout, in jiffies
710 : *
711 : * The process is put to sleep (TASK_IDLE) until the
712 : * @condition evaluates to true. The @condition is checked each time
713 : * the waitqueue @wq_head is woken up.
714 : *
715 : * wake_up() has to be called after changing any variable that could
716 : * change the result of the wait condition.
717 : *
718 : * Returns:
719 : * 0 if the @condition evaluated to %false after the @timeout elapsed,
720 : * 1 if the @condition evaluated to %true after the @timeout elapsed,
721 : * or the remaining jiffies (at least 1) if the @condition evaluated
722 : * to %true before the @timeout elapsed.
723 : */
724 : #define wait_event_idle_timeout(wq_head, condition, timeout) \
725 : ({ \
726 : long __ret = timeout; \
727 : might_sleep(); \
728 : if (!___wait_cond_timeout(condition)) \
729 : __ret = __wait_event_idle_timeout(wq_head, condition, timeout); \
730 : __ret; \
731 : })
732 :
733 : #define __wait_event_idle_exclusive_timeout(wq_head, condition, timeout) \
734 : ___wait_event(wq_head, ___wait_cond_timeout(condition), \
735 : TASK_IDLE, 1, timeout, \
736 : __ret = schedule_timeout(__ret))
737 :
738 : /**
739 : * wait_event_idle_exclusive_timeout - sleep without load until a condition becomes true or a timeout elapses
740 : * @wq_head: the waitqueue to wait on
741 : * @condition: a C expression for the event to wait for
742 : * @timeout: timeout, in jiffies
743 : *
744 : * The process is put to sleep (TASK_IDLE) until the
745 : * @condition evaluates to true. The @condition is checked each time
746 : * the waitqueue @wq_head is woken up.
747 : *
748 : * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
749 : * set thus if other processes wait on the same list, when this
750 : * process is woken further processes are not considered.
751 : *
752 : * wake_up() has to be called after changing any variable that could
753 : * change the result of the wait condition.
754 : *
755 : * Returns:
756 : * 0 if the @condition evaluated to %false after the @timeout elapsed,
757 : * 1 if the @condition evaluated to %true after the @timeout elapsed,
758 : * or the remaining jiffies (at least 1) if the @condition evaluated
759 : * to %true before the @timeout elapsed.
760 : */
761 : #define wait_event_idle_exclusive_timeout(wq_head, condition, timeout) \
762 : ({ \
763 : long __ret = timeout; \
764 : might_sleep(); \
765 : if (!___wait_cond_timeout(condition)) \
766 : __ret = __wait_event_idle_exclusive_timeout(wq_head, condition, timeout);\
767 : __ret; \
768 : })
769 :
770 : extern int do_wait_intr(wait_queue_head_t *, wait_queue_entry_t *);
771 : extern int do_wait_intr_irq(wait_queue_head_t *, wait_queue_entry_t *);
772 :
773 : #define __wait_event_interruptible_locked(wq, condition, exclusive, fn) \
774 : ({ \
775 : int __ret; \
776 : DEFINE_WAIT(__wait); \
777 : if (exclusive) \
778 : __wait.flags |= WQ_FLAG_EXCLUSIVE; \
779 : do { \
780 : __ret = fn(&(wq), &__wait); \
781 : if (__ret) \
782 : break; \
783 : } while (!(condition)); \
784 : __remove_wait_queue(&(wq), &__wait); \
785 : __set_current_state(TASK_RUNNING); \
786 : __ret; \
787 : })
788 :
789 :
790 : /**
791 : * wait_event_interruptible_locked - sleep until a condition gets true
792 : * @wq: the waitqueue to wait on
793 : * @condition: a C expression for the event to wait for
794 : *
795 : * The process is put to sleep (TASK_INTERRUPTIBLE) until the
796 : * @condition evaluates to true or a signal is received.
797 : * The @condition is checked each time the waitqueue @wq is woken up.
798 : *
799 : * It must be called with wq.lock being held. This spinlock is
800 : * unlocked while sleeping but @condition testing is done while lock
801 : * is held and when this macro exits the lock is held.
802 : *
803 : * The lock is locked/unlocked using spin_lock()/spin_unlock()
804 : * functions which must match the way they are locked/unlocked outside
805 : * of this macro.
806 : *
807 : * wake_up_locked() has to be called after changing any variable that could
808 : * change the result of the wait condition.
809 : *
810 : * The function will return -ERESTARTSYS if it was interrupted by a
811 : * signal and 0 if @condition evaluated to true.
812 : */
813 : #define wait_event_interruptible_locked(wq, condition) \
814 : ((condition) \
815 : ? 0 : __wait_event_interruptible_locked(wq, condition, 0, do_wait_intr))
816 :
817 : /**
818 : * wait_event_interruptible_locked_irq - sleep until a condition gets true
819 : * @wq: the waitqueue to wait on
820 : * @condition: a C expression for the event to wait for
821 : *
822 : * The process is put to sleep (TASK_INTERRUPTIBLE) until the
823 : * @condition evaluates to true or a signal is received.
824 : * The @condition is checked each time the waitqueue @wq is woken up.
825 : *
826 : * It must be called with wq.lock being held. This spinlock is
827 : * unlocked while sleeping but @condition testing is done while lock
828 : * is held and when this macro exits the lock is held.
829 : *
830 : * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq()
831 : * functions which must match the way they are locked/unlocked outside
832 : * of this macro.
833 : *
834 : * wake_up_locked() has to be called after changing any variable that could
835 : * change the result of the wait condition.
836 : *
837 : * The function will return -ERESTARTSYS if it was interrupted by a
838 : * signal and 0 if @condition evaluated to true.
839 : */
840 : #define wait_event_interruptible_locked_irq(wq, condition) \
841 : ((condition) \
842 : ? 0 : __wait_event_interruptible_locked(wq, condition, 0, do_wait_intr_irq))
843 :
844 : /**
845 : * wait_event_interruptible_exclusive_locked - sleep exclusively until a condition gets true
846 : * @wq: the waitqueue to wait on
847 : * @condition: a C expression for the event to wait for
848 : *
849 : * The process is put to sleep (TASK_INTERRUPTIBLE) until the
850 : * @condition evaluates to true or a signal is received.
851 : * The @condition is checked each time the waitqueue @wq is woken up.
852 : *
853 : * It must be called with wq.lock being held. This spinlock is
854 : * unlocked while sleeping but @condition testing is done while lock
855 : * is held and when this macro exits the lock is held.
856 : *
857 : * The lock is locked/unlocked using spin_lock()/spin_unlock()
858 : * functions which must match the way they are locked/unlocked outside
859 : * of this macro.
860 : *
861 : * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
862 : * set thus when other process waits process on the list if this
863 : * process is awaken further processes are not considered.
864 : *
865 : * wake_up_locked() has to be called after changing any variable that could
866 : * change the result of the wait condition.
867 : *
868 : * The function will return -ERESTARTSYS if it was interrupted by a
869 : * signal and 0 if @condition evaluated to true.
870 : */
871 : #define wait_event_interruptible_exclusive_locked(wq, condition) \
872 : ((condition) \
873 : ? 0 : __wait_event_interruptible_locked(wq, condition, 1, do_wait_intr))
874 :
875 : /**
876 : * wait_event_interruptible_exclusive_locked_irq - sleep until a condition gets true
877 : * @wq: the waitqueue to wait on
878 : * @condition: a C expression for the event to wait for
879 : *
880 : * The process is put to sleep (TASK_INTERRUPTIBLE) until the
881 : * @condition evaluates to true or a signal is received.
882 : * The @condition is checked each time the waitqueue @wq is woken up.
883 : *
884 : * It must be called with wq.lock being held. This spinlock is
885 : * unlocked while sleeping but @condition testing is done while lock
886 : * is held and when this macro exits the lock is held.
887 : *
888 : * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq()
889 : * functions which must match the way they are locked/unlocked outside
890 : * of this macro.
891 : *
892 : * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
893 : * set thus when other process waits process on the list if this
894 : * process is awaken further processes are not considered.
895 : *
896 : * wake_up_locked() has to be called after changing any variable that could
897 : * change the result of the wait condition.
898 : *
899 : * The function will return -ERESTARTSYS if it was interrupted by a
900 : * signal and 0 if @condition evaluated to true.
901 : */
902 : #define wait_event_interruptible_exclusive_locked_irq(wq, condition) \
903 : ((condition) \
904 : ? 0 : __wait_event_interruptible_locked(wq, condition, 1, do_wait_intr_irq))
905 :
906 :
907 : #define __wait_event_killable(wq, condition) \
908 : ___wait_event(wq, condition, TASK_KILLABLE, 0, 0, schedule())
909 :
910 : /**
911 : * wait_event_killable - sleep until a condition gets true
912 : * @wq_head: the waitqueue to wait on
913 : * @condition: a C expression for the event to wait for
914 : *
915 : * The process is put to sleep (TASK_KILLABLE) until the
916 : * @condition evaluates to true or a signal is received.
917 : * The @condition is checked each time the waitqueue @wq_head is woken up.
918 : *
919 : * wake_up() has to be called after changing any variable that could
920 : * change the result of the wait condition.
921 : *
922 : * The function will return -ERESTARTSYS if it was interrupted by a
923 : * signal and 0 if @condition evaluated to true.
924 : */
925 : #define wait_event_killable(wq_head, condition) \
926 : ({ \
927 : int __ret = 0; \
928 : might_sleep(); \
929 : if (!(condition)) \
930 : __ret = __wait_event_killable(wq_head, condition); \
931 : __ret; \
932 : })
933 :
934 : #define __wait_event_killable_timeout(wq_head, condition, timeout) \
935 : ___wait_event(wq_head, ___wait_cond_timeout(condition), \
936 : TASK_KILLABLE, 0, timeout, \
937 : __ret = schedule_timeout(__ret))
938 :
939 : /**
940 : * wait_event_killable_timeout - sleep until a condition gets true or a timeout elapses
941 : * @wq_head: the waitqueue to wait on
942 : * @condition: a C expression for the event to wait for
943 : * @timeout: timeout, in jiffies
944 : *
945 : * The process is put to sleep (TASK_KILLABLE) until the
946 : * @condition evaluates to true or a kill signal is received.
947 : * The @condition is checked each time the waitqueue @wq_head is woken up.
948 : *
949 : * wake_up() has to be called after changing any variable that could
950 : * change the result of the wait condition.
951 : *
952 : * Returns:
953 : * 0 if the @condition evaluated to %false after the @timeout elapsed,
954 : * 1 if the @condition evaluated to %true after the @timeout elapsed,
955 : * the remaining jiffies (at least 1) if the @condition evaluated
956 : * to %true before the @timeout elapsed, or -%ERESTARTSYS if it was
957 : * interrupted by a kill signal.
958 : *
959 : * Only kill signals interrupt this process.
960 : */
961 : #define wait_event_killable_timeout(wq_head, condition, timeout) \
962 : ({ \
963 : long __ret = timeout; \
964 : might_sleep(); \
965 : if (!___wait_cond_timeout(condition)) \
966 : __ret = __wait_event_killable_timeout(wq_head, \
967 : condition, timeout); \
968 : __ret; \
969 : })
970 :
971 :
972 : #define __wait_event_lock_irq(wq_head, condition, lock, cmd) \
973 : (void)___wait_event(wq_head, condition, TASK_UNINTERRUPTIBLE, 0, 0, \
974 : spin_unlock_irq(&lock); \
975 : cmd; \
976 : schedule(); \
977 : spin_lock_irq(&lock))
978 :
979 : /**
980 : * wait_event_lock_irq_cmd - sleep until a condition gets true. The
981 : * condition is checked under the lock. This
982 : * is expected to be called with the lock
983 : * taken.
984 : * @wq_head: the waitqueue to wait on
985 : * @condition: a C expression for the event to wait for
986 : * @lock: a locked spinlock_t, which will be released before cmd
987 : * and schedule() and reacquired afterwards.
988 : * @cmd: a command which is invoked outside the critical section before
989 : * sleep
990 : *
991 : * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
992 : * @condition evaluates to true. The @condition is checked each time
993 : * the waitqueue @wq_head is woken up.
994 : *
995 : * wake_up() has to be called after changing any variable that could
996 : * change the result of the wait condition.
997 : *
998 : * This is supposed to be called while holding the lock. The lock is
999 : * dropped before invoking the cmd and going to sleep and is reacquired
1000 : * afterwards.
1001 : */
1002 : #define wait_event_lock_irq_cmd(wq_head, condition, lock, cmd) \
1003 : do { \
1004 : if (condition) \
1005 : break; \
1006 : __wait_event_lock_irq(wq_head, condition, lock, cmd); \
1007 : } while (0)
1008 :
1009 : /**
1010 : * wait_event_lock_irq - sleep until a condition gets true. The
1011 : * condition is checked under the lock. This
1012 : * is expected to be called with the lock
1013 : * taken.
1014 : * @wq_head: the waitqueue to wait on
1015 : * @condition: a C expression for the event to wait for
1016 : * @lock: a locked spinlock_t, which will be released before schedule()
1017 : * and reacquired afterwards.
1018 : *
1019 : * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
1020 : * @condition evaluates to true. The @condition is checked each time
1021 : * the waitqueue @wq_head is woken up.
1022 : *
1023 : * wake_up() has to be called after changing any variable that could
1024 : * change the result of the wait condition.
1025 : *
1026 : * This is supposed to be called while holding the lock. The lock is
1027 : * dropped before going to sleep and is reacquired afterwards.
1028 : */
1029 : #define wait_event_lock_irq(wq_head, condition, lock) \
1030 : do { \
1031 : if (condition) \
1032 : break; \
1033 : __wait_event_lock_irq(wq_head, condition, lock, ); \
1034 : } while (0)
1035 :
1036 :
1037 : #define __wait_event_interruptible_lock_irq(wq_head, condition, lock, cmd) \
1038 : ___wait_event(wq_head, condition, TASK_INTERRUPTIBLE, 0, 0, \
1039 : spin_unlock_irq(&lock); \
1040 : cmd; \
1041 : schedule(); \
1042 : spin_lock_irq(&lock))
1043 :
1044 : /**
1045 : * wait_event_interruptible_lock_irq_cmd - sleep until a condition gets true.
1046 : * The condition is checked under the lock. This is expected to
1047 : * be called with the lock taken.
1048 : * @wq_head: the waitqueue to wait on
1049 : * @condition: a C expression for the event to wait for
1050 : * @lock: a locked spinlock_t, which will be released before cmd and
1051 : * schedule() and reacquired afterwards.
1052 : * @cmd: a command which is invoked outside the critical section before
1053 : * sleep
1054 : *
1055 : * The process is put to sleep (TASK_INTERRUPTIBLE) until the
1056 : * @condition evaluates to true or a signal is received. The @condition is
1057 : * checked each time the waitqueue @wq_head is woken up.
1058 : *
1059 : * wake_up() has to be called after changing any variable that could
1060 : * change the result of the wait condition.
1061 : *
1062 : * This is supposed to be called while holding the lock. The lock is
1063 : * dropped before invoking the cmd and going to sleep and is reacquired
1064 : * afterwards.
1065 : *
1066 : * The macro will return -ERESTARTSYS if it was interrupted by a signal
1067 : * and 0 if @condition evaluated to true.
1068 : */
1069 : #define wait_event_interruptible_lock_irq_cmd(wq_head, condition, lock, cmd) \
1070 : ({ \
1071 : int __ret = 0; \
1072 : if (!(condition)) \
1073 : __ret = __wait_event_interruptible_lock_irq(wq_head, \
1074 : condition, lock, cmd); \
1075 : __ret; \
1076 : })
1077 :
1078 : /**
1079 : * wait_event_interruptible_lock_irq - sleep until a condition gets true.
1080 : * The condition is checked under the lock. This is expected
1081 : * to be called with the lock taken.
1082 : * @wq_head: the waitqueue to wait on
1083 : * @condition: a C expression for the event to wait for
1084 : * @lock: a locked spinlock_t, which will be released before schedule()
1085 : * and reacquired afterwards.
1086 : *
1087 : * The process is put to sleep (TASK_INTERRUPTIBLE) until the
1088 : * @condition evaluates to true or signal is received. The @condition is
1089 : * checked each time the waitqueue @wq_head is woken up.
1090 : *
1091 : * wake_up() has to be called after changing any variable that could
1092 : * change the result of the wait condition.
1093 : *
1094 : * This is supposed to be called while holding the lock. The lock is
1095 : * dropped before going to sleep and is reacquired afterwards.
1096 : *
1097 : * The macro will return -ERESTARTSYS if it was interrupted by a signal
1098 : * and 0 if @condition evaluated to true.
1099 : */
1100 : #define wait_event_interruptible_lock_irq(wq_head, condition, lock) \
1101 : ({ \
1102 : int __ret = 0; \
1103 : if (!(condition)) \
1104 : __ret = __wait_event_interruptible_lock_irq(wq_head, \
1105 : condition, lock,); \
1106 : __ret; \
1107 : })
1108 :
1109 : #define __wait_event_lock_irq_timeout(wq_head, condition, lock, timeout, state) \
1110 : ___wait_event(wq_head, ___wait_cond_timeout(condition), \
1111 : state, 0, timeout, \
1112 : spin_unlock_irq(&lock); \
1113 : __ret = schedule_timeout(__ret); \
1114 : spin_lock_irq(&lock));
1115 :
1116 : /**
1117 : * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets
1118 : * true or a timeout elapses. The condition is checked under
1119 : * the lock. This is expected to be called with the lock taken.
1120 : * @wq_head: the waitqueue to wait on
1121 : * @condition: a C expression for the event to wait for
1122 : * @lock: a locked spinlock_t, which will be released before schedule()
1123 : * and reacquired afterwards.
1124 : * @timeout: timeout, in jiffies
1125 : *
1126 : * The process is put to sleep (TASK_INTERRUPTIBLE) until the
1127 : * @condition evaluates to true or signal is received. The @condition is
1128 : * checked each time the waitqueue @wq_head is woken up.
1129 : *
1130 : * wake_up() has to be called after changing any variable that could
1131 : * change the result of the wait condition.
1132 : *
1133 : * This is supposed to be called while holding the lock. The lock is
1134 : * dropped before going to sleep and is reacquired afterwards.
1135 : *
1136 : * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
1137 : * was interrupted by a signal, and the remaining jiffies otherwise
1138 : * if the condition evaluated to true before the timeout elapsed.
1139 : */
1140 : #define wait_event_interruptible_lock_irq_timeout(wq_head, condition, lock, \
1141 : timeout) \
1142 : ({ \
1143 : long __ret = timeout; \
1144 : if (!___wait_cond_timeout(condition)) \
1145 : __ret = __wait_event_lock_irq_timeout( \
1146 : wq_head, condition, lock, timeout, \
1147 : TASK_INTERRUPTIBLE); \
1148 : __ret; \
1149 : })
1150 :
1151 : #define wait_event_lock_irq_timeout(wq_head, condition, lock, timeout) \
1152 : ({ \
1153 : long __ret = timeout; \
1154 : if (!___wait_cond_timeout(condition)) \
1155 : __ret = __wait_event_lock_irq_timeout( \
1156 : wq_head, condition, lock, timeout, \
1157 : TASK_UNINTERRUPTIBLE); \
1158 : __ret; \
1159 : })
1160 :
1161 : /*
1162 : * Waitqueues which are removed from the waitqueue_head at wakeup time
1163 : */
1164 : void prepare_to_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state);
1165 : bool prepare_to_wait_exclusive(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state);
1166 : long prepare_to_wait_event(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry, int state);
1167 : void finish_wait(struct wait_queue_head *wq_head, struct wait_queue_entry *wq_entry);
1168 : long wait_woken(struct wait_queue_entry *wq_entry, unsigned mode, long timeout);
1169 : int woken_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key);
1170 : int autoremove_wake_function(struct wait_queue_entry *wq_entry, unsigned mode, int sync, void *key);
1171 :
1172 : #define DEFINE_WAIT_FUNC(name, function) \
1173 : struct wait_queue_entry name = { \
1174 : .private = current, \
1175 : .func = function, \
1176 : .entry = LIST_HEAD_INIT((name).entry), \
1177 : }
1178 :
1179 : #define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function)
1180 :
1181 : #define init_wait(wait) \
1182 : do { \
1183 : (wait)->private = current; \
1184 : (wait)->func = autoremove_wake_function; \
1185 : INIT_LIST_HEAD(&(wait)->entry); \
1186 : (wait)->flags = 0; \
1187 : } while (0)
1188 :
1189 : typedef int (*task_call_f)(struct task_struct *p, void *arg);
1190 : extern int task_call_func(struct task_struct *p, task_call_f func, void *arg);
1191 :
1192 : #endif /* _LINUX_WAIT_H */
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