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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 | |
8b32201d PZ |
251 | /* |
252 | * The below macro ___wait_event() has an explicit shadow of the __ret | |
253 | * variable when used from the wait_event_*() macros. | |
254 | * | |
255 | * This is so that both can use the ___wait_cond_timeout() construct | |
256 | * to wrap the condition. | |
257 | * | |
258 | * The type inconsistency of the wait_event_*() __ret variable is also | |
259 | * on purpose; we use long where we can return timeout values and int | |
260 | * otherwise. | |
261 | */ | |
262 | ||
41a1431b | 263 | #define ___wait_event(wq, condition, state, exclusive, ret, cmd) \ |
35a2af94 | 264 | ({ \ |
41a1431b | 265 | __label__ __out; \ |
c2d81644 | 266 | wait_queue_t __wait; \ |
8b32201d | 267 | long __ret = ret; /* explicit shadow */ \ |
41a1431b | 268 | \ |
c2d81644 ON |
269 | INIT_LIST_HEAD(&__wait.task_list); \ |
270 | if (exclusive) \ | |
271 | __wait.flags = WQ_FLAG_EXCLUSIVE; \ | |
272 | else \ | |
273 | __wait.flags = 0; \ | |
274 | \ | |
41a1431b | 275 | for (;;) { \ |
c2d81644 | 276 | long __int = prepare_to_wait_event(&wq, &__wait, state);\ |
41a1431b PZ |
277 | \ |
278 | if (condition) \ | |
279 | break; \ | |
280 | \ | |
c2d81644 ON |
281 | if (___wait_is_interruptible(state) && __int) { \ |
282 | __ret = __int; \ | |
41a1431b | 283 | if (exclusive) { \ |
fb869b6e IM |
284 | abort_exclusive_wait(&wq, &__wait, \ |
285 | state, NULL); \ | |
41a1431b PZ |
286 | goto __out; \ |
287 | } \ | |
288 | break; \ | |
289 | } \ | |
290 | \ | |
291 | cmd; \ | |
292 | } \ | |
293 | finish_wait(&wq, &__wait); \ | |
35a2af94 PZ |
294 | __out: __ret; \ |
295 | }) | |
41a1431b | 296 | |
fb869b6e | 297 | #define __wait_event(wq, condition) \ |
35a2af94 PZ |
298 | (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ |
299 | schedule()) | |
1da177e4 LT |
300 | |
301 | /** | |
302 | * wait_event - sleep until a condition gets true | |
303 | * @wq: the waitqueue to wait on | |
304 | * @condition: a C expression for the event to wait for | |
305 | * | |
306 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
307 | * @condition evaluates to true. The @condition is checked each time | |
308 | * the waitqueue @wq is woken up. | |
309 | * | |
310 | * wake_up() has to be called after changing any variable that could | |
311 | * change the result of the wait condition. | |
312 | */ | |
fb869b6e | 313 | #define wait_event(wq, condition) \ |
1da177e4 | 314 | do { \ |
e22b886a | 315 | might_sleep(); \ |
fb869b6e | 316 | if (condition) \ |
1da177e4 LT |
317 | break; \ |
318 | __wait_event(wq, condition); \ | |
319 | } while (0) | |
320 | ||
2c561246 PZ |
321 | #define __io_wait_event(wq, condition) \ |
322 | (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ | |
323 | io_schedule()) | |
324 | ||
325 | /* | |
326 | * io_wait_event() -- like wait_event() but with io_schedule() | |
327 | */ | |
328 | #define io_wait_event(wq, condition) \ | |
329 | do { \ | |
330 | might_sleep(); \ | |
331 | if (condition) \ | |
332 | break; \ | |
333 | __io_wait_event(wq, condition); \ | |
334 | } while (0) | |
335 | ||
36df04bc PZ |
336 | #define __wait_event_freezable(wq, condition) \ |
337 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ | |
338 | schedule(); try_to_freeze()) | |
339 | ||
340 | /** | |
f4bcfa1d | 341 | * wait_event_freezable - sleep (or freeze) until a condition gets true |
36df04bc PZ |
342 | * @wq: the waitqueue to wait on |
343 | * @condition: a C expression for the event to wait for | |
344 | * | |
345 | * The process is put to sleep (TASK_INTERRUPTIBLE -- so as not to contribute | |
346 | * to system load) until the @condition evaluates to true. The | |
347 | * @condition is checked each time the waitqueue @wq is woken up. | |
348 | * | |
349 | * wake_up() has to be called after changing any variable that could | |
350 | * change the result of the wait condition. | |
351 | */ | |
352 | #define wait_event_freezable(wq, condition) \ | |
353 | ({ \ | |
354 | int __ret = 0; \ | |
355 | might_sleep(); \ | |
356 | if (!(condition)) \ | |
357 | __ret = __wait_event_freezable(wq, condition); \ | |
358 | __ret; \ | |
359 | }) | |
360 | ||
35a2af94 PZ |
361 | #define __wait_event_timeout(wq, condition, timeout) \ |
362 | ___wait_event(wq, ___wait_cond_timeout(condition), \ | |
363 | TASK_UNINTERRUPTIBLE, 0, timeout, \ | |
364 | __ret = schedule_timeout(__ret)) | |
1da177e4 LT |
365 | |
366 | /** | |
367 | * wait_event_timeout - sleep until a condition gets true or a timeout elapses | |
368 | * @wq: the waitqueue to wait on | |
369 | * @condition: a C expression for the event to wait for | |
370 | * @timeout: timeout, in jiffies | |
371 | * | |
372 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
373 | * @condition evaluates to true. The @condition is checked each time | |
374 | * the waitqueue @wq 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 | * | |
6b44f519 SD |
379 | * Returns: |
380 | * 0 if the @condition evaluated to %false after the @timeout elapsed, | |
381 | * 1 if the @condition evaluated to %true after the @timeout elapsed, | |
382 | * or the remaining jiffies (at least 1) if the @condition evaluated | |
383 | * to %true before the @timeout elapsed. | |
1da177e4 LT |
384 | */ |
385 | #define wait_event_timeout(wq, condition, timeout) \ | |
386 | ({ \ | |
387 | long __ret = timeout; \ | |
e22b886a | 388 | might_sleep(); \ |
8922915b | 389 | if (!___wait_cond_timeout(condition)) \ |
35a2af94 | 390 | __ret = __wait_event_timeout(wq, condition, timeout); \ |
1da177e4 LT |
391 | __ret; \ |
392 | }) | |
393 | ||
36df04bc PZ |
394 | #define __wait_event_freezable_timeout(wq, condition, timeout) \ |
395 | ___wait_event(wq, ___wait_cond_timeout(condition), \ | |
396 | TASK_INTERRUPTIBLE, 0, timeout, \ | |
397 | __ret = schedule_timeout(__ret); try_to_freeze()) | |
398 | ||
399 | /* | |
400 | * like wait_event_timeout() -- except it uses TASK_INTERRUPTIBLE to avoid | |
401 | * increasing load and is freezable. | |
402 | */ | |
403 | #define wait_event_freezable_timeout(wq, condition, timeout) \ | |
404 | ({ \ | |
405 | long __ret = timeout; \ | |
406 | might_sleep(); \ | |
407 | if (!___wait_cond_timeout(condition)) \ | |
408 | __ret = __wait_event_freezable_timeout(wq, condition, timeout); \ | |
409 | __ret; \ | |
410 | }) | |
411 | ||
9f3520c3 YL |
412 | #define __wait_event_exclusive_cmd(wq, condition, cmd1, cmd2) \ |
413 | (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 1, 0, \ | |
414 | cmd1; schedule(); cmd2) | |
415 | /* | |
416 | * Just like wait_event_cmd(), except it sets exclusive flag | |
417 | */ | |
418 | #define wait_event_exclusive_cmd(wq, condition, cmd1, cmd2) \ | |
419 | do { \ | |
420 | if (condition) \ | |
421 | break; \ | |
422 | __wait_event_exclusive_cmd(wq, condition, cmd1, cmd2); \ | |
423 | } while (0) | |
424 | ||
82e06c81 SL |
425 | #define __wait_event_cmd(wq, condition, cmd1, cmd2) \ |
426 | (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ | |
427 | cmd1; schedule(); cmd2) | |
428 | ||
429 | /** | |
430 | * wait_event_cmd - sleep until a condition gets true | |
431 | * @wq: the waitqueue to wait on | |
432 | * @condition: a C expression for the event to wait for | |
f434f7af MI |
433 | * @cmd1: the command will be executed before sleep |
434 | * @cmd2: the command will be executed after sleep | |
82e06c81 SL |
435 | * |
436 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
437 | * @condition evaluates to true. The @condition is checked each time | |
438 | * the waitqueue @wq is woken up. | |
439 | * | |
440 | * wake_up() has to be called after changing any variable that could | |
441 | * change the result of the wait condition. | |
442 | */ | |
443 | #define wait_event_cmd(wq, condition, cmd1, cmd2) \ | |
444 | do { \ | |
445 | if (condition) \ | |
446 | break; \ | |
447 | __wait_event_cmd(wq, condition, cmd1, cmd2); \ | |
448 | } while (0) | |
449 | ||
35a2af94 PZ |
450 | #define __wait_event_interruptible(wq, condition) \ |
451 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ | |
f13f4c41 | 452 | schedule()) |
1da177e4 LT |
453 | |
454 | /** | |
455 | * wait_event_interruptible - sleep until a condition gets true | |
456 | * @wq: the waitqueue to wait on | |
457 | * @condition: a C expression for the event to wait for | |
458 | * | |
459 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
460 | * @condition evaluates to true or a signal is received. | |
461 | * The @condition is checked each time the waitqueue @wq is woken up. | |
462 | * | |
463 | * wake_up() has to be called after changing any variable that could | |
464 | * change the result of the wait condition. | |
465 | * | |
466 | * The function will return -ERESTARTSYS if it was interrupted by a | |
467 | * signal and 0 if @condition evaluated to true. | |
468 | */ | |
469 | #define wait_event_interruptible(wq, condition) \ | |
470 | ({ \ | |
471 | int __ret = 0; \ | |
e22b886a | 472 | might_sleep(); \ |
1da177e4 | 473 | if (!(condition)) \ |
35a2af94 | 474 | __ret = __wait_event_interruptible(wq, condition); \ |
1da177e4 LT |
475 | __ret; \ |
476 | }) | |
477 | ||
35a2af94 PZ |
478 | #define __wait_event_interruptible_timeout(wq, condition, timeout) \ |
479 | ___wait_event(wq, ___wait_cond_timeout(condition), \ | |
480 | TASK_INTERRUPTIBLE, 0, timeout, \ | |
481 | __ret = schedule_timeout(__ret)) | |
1da177e4 LT |
482 | |
483 | /** | |
484 | * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses | |
485 | * @wq: the waitqueue to wait on | |
486 | * @condition: a C expression for the event to wait for | |
487 | * @timeout: timeout, in jiffies | |
488 | * | |
489 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
490 | * @condition evaluates to true or a signal is received. | |
491 | * The @condition is checked each time the waitqueue @wq is woken up. | |
492 | * | |
493 | * wake_up() has to be called after changing any variable that could | |
494 | * change the result of the wait condition. | |
495 | * | |
4c663cfc | 496 | * Returns: |
6b44f519 SD |
497 | * 0 if the @condition evaluated to %false after the @timeout elapsed, |
498 | * 1 if the @condition evaluated to %true after the @timeout elapsed, | |
499 | * the remaining jiffies (at least 1) if the @condition evaluated | |
500 | * to %true before the @timeout elapsed, or -%ERESTARTSYS if it was | |
501 | * interrupted by a signal. | |
1da177e4 LT |
502 | */ |
503 | #define wait_event_interruptible_timeout(wq, condition, timeout) \ | |
504 | ({ \ | |
505 | long __ret = timeout; \ | |
e22b886a | 506 | might_sleep(); \ |
8922915b | 507 | if (!___wait_cond_timeout(condition)) \ |
fb869b6e | 508 | __ret = __wait_event_interruptible_timeout(wq, \ |
35a2af94 | 509 | condition, timeout); \ |
1da177e4 LT |
510 | __ret; \ |
511 | }) | |
512 | ||
774a08b3 KO |
513 | #define __wait_event_hrtimeout(wq, condition, timeout, state) \ |
514 | ({ \ | |
515 | int __ret = 0; \ | |
774a08b3 KO |
516 | struct hrtimer_sleeper __t; \ |
517 | \ | |
518 | hrtimer_init_on_stack(&__t.timer, CLOCK_MONOTONIC, \ | |
519 | HRTIMER_MODE_REL); \ | |
520 | hrtimer_init_sleeper(&__t, current); \ | |
521 | if ((timeout).tv64 != KTIME_MAX) \ | |
522 | hrtimer_start_range_ns(&__t.timer, timeout, \ | |
523 | current->timer_slack_ns, \ | |
524 | HRTIMER_MODE_REL); \ | |
525 | \ | |
35a2af94 | 526 | __ret = ___wait_event(wq, condition, state, 0, 0, \ |
774a08b3 KO |
527 | if (!__t.task) { \ |
528 | __ret = -ETIME; \ | |
529 | break; \ | |
530 | } \ | |
ebdc195f | 531 | schedule()); \ |
774a08b3 KO |
532 | \ |
533 | hrtimer_cancel(&__t.timer); \ | |
534 | destroy_hrtimer_on_stack(&__t.timer); \ | |
774a08b3 KO |
535 | __ret; \ |
536 | }) | |
537 | ||
538 | /** | |
539 | * wait_event_hrtimeout - sleep until a condition gets true or a timeout elapses | |
540 | * @wq: the waitqueue to wait on | |
541 | * @condition: a C expression for the event to wait for | |
542 | * @timeout: timeout, as a ktime_t | |
543 | * | |
544 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
545 | * @condition evaluates to true or a signal is received. | |
546 | * The @condition is checked each time the waitqueue @wq is woken up. | |
547 | * | |
548 | * wake_up() has to be called after changing any variable that could | |
549 | * change the result of the wait condition. | |
550 | * | |
551 | * The function returns 0 if @condition became true, or -ETIME if the timeout | |
552 | * elapsed. | |
553 | */ | |
554 | #define wait_event_hrtimeout(wq, condition, timeout) \ | |
555 | ({ \ | |
556 | int __ret = 0; \ | |
e22b886a | 557 | might_sleep(); \ |
774a08b3 KO |
558 | if (!(condition)) \ |
559 | __ret = __wait_event_hrtimeout(wq, condition, timeout, \ | |
560 | TASK_UNINTERRUPTIBLE); \ | |
561 | __ret; \ | |
562 | }) | |
563 | ||
564 | /** | |
565 | * wait_event_interruptible_hrtimeout - sleep until a condition gets true or a timeout elapses | |
566 | * @wq: 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_INTERRUPTIBLE) until the | |
571 | * @condition evaluates to true or a signal is received. | |
572 | * The @condition is checked each time the waitqueue @wq 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, -ERESTARTSYS if it was | |
578 | * interrupted by a signal, or -ETIME if the timeout elapsed. | |
579 | */ | |
580 | #define wait_event_interruptible_hrtimeout(wq, condition, timeout) \ | |
581 | ({ \ | |
582 | long __ret = 0; \ | |
e22b886a | 583 | might_sleep(); \ |
774a08b3 KO |
584 | if (!(condition)) \ |
585 | __ret = __wait_event_hrtimeout(wq, condition, timeout, \ | |
586 | TASK_INTERRUPTIBLE); \ | |
587 | __ret; \ | |
588 | }) | |
589 | ||
35a2af94 PZ |
590 | #define __wait_event_interruptible_exclusive(wq, condition) \ |
591 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \ | |
48c25217 | 592 | schedule()) |
1da177e4 LT |
593 | |
594 | #define wait_event_interruptible_exclusive(wq, condition) \ | |
595 | ({ \ | |
596 | int __ret = 0; \ | |
e22b886a | 597 | might_sleep(); \ |
1da177e4 | 598 | if (!(condition)) \ |
35a2af94 | 599 | __ret = __wait_event_interruptible_exclusive(wq, condition);\ |
1da177e4 LT |
600 | __ret; \ |
601 | }) | |
602 | ||
6a0fb306 AV |
603 | #define __wait_event_killable_exclusive(wq, condition) \ |
604 | ___wait_event(wq, condition, TASK_KILLABLE, 1, 0, \ | |
605 | schedule()) | |
606 | ||
607 | #define wait_event_killable_exclusive(wq, condition) \ | |
608 | ({ \ | |
609 | int __ret = 0; \ | |
610 | might_sleep(); \ | |
611 | if (!(condition)) \ | |
612 | __ret = __wait_event_killable_exclusive(wq, condition); \ | |
613 | __ret; \ | |
614 | }) | |
615 | ||
22c43c81 | 616 | |
36df04bc PZ |
617 | #define __wait_event_freezable_exclusive(wq, condition) \ |
618 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \ | |
619 | schedule(); try_to_freeze()) | |
620 | ||
621 | #define wait_event_freezable_exclusive(wq, condition) \ | |
622 | ({ \ | |
623 | int __ret = 0; \ | |
624 | might_sleep(); \ | |
625 | if (!(condition)) \ | |
626 | __ret = __wait_event_freezable_exclusive(wq, condition);\ | |
627 | __ret; \ | |
628 | }) | |
629 | ||
630 | ||
22c43c81 MN |
631 | #define __wait_event_interruptible_locked(wq, condition, exclusive, irq) \ |
632 | ({ \ | |
633 | int __ret = 0; \ | |
634 | DEFINE_WAIT(__wait); \ | |
635 | if (exclusive) \ | |
636 | __wait.flags |= WQ_FLAG_EXCLUSIVE; \ | |
637 | do { \ | |
638 | if (likely(list_empty(&__wait.task_list))) \ | |
639 | __add_wait_queue_tail(&(wq), &__wait); \ | |
640 | set_current_state(TASK_INTERRUPTIBLE); \ | |
641 | if (signal_pending(current)) { \ | |
642 | __ret = -ERESTARTSYS; \ | |
643 | break; \ | |
644 | } \ | |
645 | if (irq) \ | |
646 | spin_unlock_irq(&(wq).lock); \ | |
647 | else \ | |
648 | spin_unlock(&(wq).lock); \ | |
649 | schedule(); \ | |
650 | if (irq) \ | |
651 | spin_lock_irq(&(wq).lock); \ | |
652 | else \ | |
653 | spin_lock(&(wq).lock); \ | |
654 | } while (!(condition)); \ | |
655 | __remove_wait_queue(&(wq), &__wait); \ | |
656 | __set_current_state(TASK_RUNNING); \ | |
657 | __ret; \ | |
658 | }) | |
659 | ||
660 | ||
661 | /** | |
662 | * wait_event_interruptible_locked - sleep until a condition gets true | |
663 | * @wq: the waitqueue to wait on | |
664 | * @condition: a C expression for the event to wait for | |
665 | * | |
666 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
667 | * @condition evaluates to true or a signal is received. | |
668 | * The @condition is checked each time the waitqueue @wq is woken up. | |
669 | * | |
670 | * It must be called with wq.lock being held. This spinlock is | |
671 | * unlocked while sleeping but @condition testing is done while lock | |
672 | * is held and when this macro exits the lock is held. | |
673 | * | |
674 | * The lock is locked/unlocked using spin_lock()/spin_unlock() | |
675 | * functions which must match the way they are locked/unlocked outside | |
676 | * of this macro. | |
677 | * | |
678 | * wake_up_locked() has to be called after changing any variable that could | |
679 | * change the result of the wait condition. | |
680 | * | |
681 | * The function will return -ERESTARTSYS if it was interrupted by a | |
682 | * signal and 0 if @condition evaluated to true. | |
683 | */ | |
684 | #define wait_event_interruptible_locked(wq, condition) \ | |
685 | ((condition) \ | |
686 | ? 0 : __wait_event_interruptible_locked(wq, condition, 0, 0)) | |
687 | ||
688 | /** | |
689 | * wait_event_interruptible_locked_irq - sleep until a condition gets true | |
690 | * @wq: the waitqueue to wait on | |
691 | * @condition: a C expression for the event to wait for | |
692 | * | |
693 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
694 | * @condition evaluates to true or a signal is received. | |
695 | * The @condition is checked each time the waitqueue @wq is woken up. | |
696 | * | |
697 | * It must be called with wq.lock being held. This spinlock is | |
698 | * unlocked while sleeping but @condition testing is done while lock | |
699 | * is held and when this macro exits the lock is held. | |
700 | * | |
701 | * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq() | |
702 | * functions which must match the way they are locked/unlocked outside | |
703 | * of this macro. | |
704 | * | |
705 | * wake_up_locked() has to be called after changing any variable that could | |
706 | * change the result of the wait condition. | |
707 | * | |
708 | * The function will return -ERESTARTSYS if it was interrupted by a | |
709 | * signal and 0 if @condition evaluated to true. | |
710 | */ | |
711 | #define wait_event_interruptible_locked_irq(wq, condition) \ | |
712 | ((condition) \ | |
713 | ? 0 : __wait_event_interruptible_locked(wq, condition, 0, 1)) | |
714 | ||
715 | /** | |
716 | * wait_event_interruptible_exclusive_locked - sleep exclusively until a condition gets true | |
717 | * @wq: the waitqueue to wait on | |
718 | * @condition: a C expression for the event to wait for | |
719 | * | |
720 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
721 | * @condition evaluates to true or a signal is received. | |
722 | * The @condition is checked each time the waitqueue @wq is woken up. | |
723 | * | |
724 | * It must be called with wq.lock being held. This spinlock is | |
725 | * unlocked while sleeping but @condition testing is done while lock | |
726 | * is held and when this macro exits the lock is held. | |
727 | * | |
728 | * The lock is locked/unlocked using spin_lock()/spin_unlock() | |
729 | * functions which must match the way they are locked/unlocked outside | |
730 | * of this macro. | |
731 | * | |
732 | * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag | |
733 | * set thus when other process waits process on the list if this | |
734 | * process is awaken further processes are not considered. | |
735 | * | |
736 | * wake_up_locked() has to be called after changing any variable that could | |
737 | * change the result of the wait condition. | |
738 | * | |
739 | * The function will return -ERESTARTSYS if it was interrupted by a | |
740 | * signal and 0 if @condition evaluated to true. | |
741 | */ | |
742 | #define wait_event_interruptible_exclusive_locked(wq, condition) \ | |
743 | ((condition) \ | |
744 | ? 0 : __wait_event_interruptible_locked(wq, condition, 1, 0)) | |
745 | ||
746 | /** | |
747 | * wait_event_interruptible_exclusive_locked_irq - sleep until a condition gets true | |
748 | * @wq: the waitqueue to wait on | |
749 | * @condition: a C expression for the event to wait for | |
750 | * | |
751 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
752 | * @condition evaluates to true or a signal is received. | |
753 | * The @condition is checked each time the waitqueue @wq is woken up. | |
754 | * | |
755 | * It must be called with wq.lock being held. This spinlock is | |
756 | * unlocked while sleeping but @condition testing is done while lock | |
757 | * is held and when this macro exits the lock is held. | |
758 | * | |
759 | * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq() | |
760 | * functions which must match the way they are locked/unlocked outside | |
761 | * of this macro. | |
762 | * | |
763 | * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag | |
764 | * set thus when other process waits process on the list if this | |
765 | * process is awaken further processes are not considered. | |
766 | * | |
767 | * wake_up_locked() has to be called after changing any variable that could | |
768 | * change the result of the wait condition. | |
769 | * | |
770 | * The function will return -ERESTARTSYS if it was interrupted by a | |
771 | * signal and 0 if @condition evaluated to true. | |
772 | */ | |
773 | #define wait_event_interruptible_exclusive_locked_irq(wq, condition) \ | |
774 | ((condition) \ | |
775 | ? 0 : __wait_event_interruptible_locked(wq, condition, 1, 1)) | |
776 | ||
777 | ||
35a2af94 PZ |
778 | #define __wait_event_killable(wq, condition) \ |
779 | ___wait_event(wq, condition, TASK_KILLABLE, 0, 0, schedule()) | |
1411d5a7 MW |
780 | |
781 | /** | |
782 | * wait_event_killable - sleep until a condition gets true | |
783 | * @wq: the waitqueue to wait on | |
784 | * @condition: a C expression for the event to wait for | |
785 | * | |
786 | * The process is put to sleep (TASK_KILLABLE) until the | |
787 | * @condition evaluates to true or a signal is received. | |
788 | * The @condition is checked each time the waitqueue @wq is woken up. | |
789 | * | |
790 | * wake_up() has to be called after changing any variable that could | |
791 | * change the result of the wait condition. | |
792 | * | |
793 | * The function will return -ERESTARTSYS if it was interrupted by a | |
794 | * signal and 0 if @condition evaluated to true. | |
795 | */ | |
796 | #define wait_event_killable(wq, condition) \ | |
797 | ({ \ | |
798 | int __ret = 0; \ | |
e22b886a | 799 | might_sleep(); \ |
1411d5a7 | 800 | if (!(condition)) \ |
35a2af94 | 801 | __ret = __wait_event_killable(wq, condition); \ |
1411d5a7 MW |
802 | __ret; \ |
803 | }) | |
804 | ||
eed8c02e LC |
805 | |
806 | #define __wait_event_lock_irq(wq, condition, lock, cmd) \ | |
35a2af94 PZ |
807 | (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ |
808 | spin_unlock_irq(&lock); \ | |
809 | cmd; \ | |
810 | schedule(); \ | |
811 | spin_lock_irq(&lock)) | |
eed8c02e LC |
812 | |
813 | /** | |
814 | * wait_event_lock_irq_cmd - sleep until a condition gets true. The | |
815 | * condition is checked under the lock. This | |
816 | * is expected to be called with the lock | |
817 | * taken. | |
818 | * @wq: the waitqueue to wait on | |
819 | * @condition: a C expression for the event to wait for | |
820 | * @lock: a locked spinlock_t, which will be released before cmd | |
821 | * and schedule() and reacquired afterwards. | |
822 | * @cmd: a command which is invoked outside the critical section before | |
823 | * sleep | |
824 | * | |
825 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
826 | * @condition evaluates to true. The @condition is checked each time | |
827 | * the waitqueue @wq is woken up. | |
828 | * | |
829 | * wake_up() has to be called after changing any variable that could | |
830 | * change the result of the wait condition. | |
831 | * | |
832 | * This is supposed to be called while holding the lock. The lock is | |
833 | * dropped before invoking the cmd and going to sleep and is reacquired | |
834 | * afterwards. | |
835 | */ | |
836 | #define wait_event_lock_irq_cmd(wq, condition, lock, cmd) \ | |
837 | do { \ | |
838 | if (condition) \ | |
839 | break; \ | |
840 | __wait_event_lock_irq(wq, condition, lock, cmd); \ | |
841 | } while (0) | |
842 | ||
843 | /** | |
844 | * wait_event_lock_irq - sleep until a condition gets true. The | |
845 | * condition is checked under the lock. This | |
846 | * is expected to be called with the lock | |
847 | * taken. | |
848 | * @wq: the waitqueue to wait on | |
849 | * @condition: a C expression for the event to wait for | |
850 | * @lock: a locked spinlock_t, which will be released before schedule() | |
851 | * and reacquired afterwards. | |
852 | * | |
853 | * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the | |
854 | * @condition evaluates to true. The @condition is checked each time | |
855 | * the waitqueue @wq is woken up. | |
856 | * | |
857 | * wake_up() has to be called after changing any variable that could | |
858 | * change the result of the wait condition. | |
859 | * | |
860 | * This is supposed to be called while holding the lock. The lock is | |
861 | * dropped before going to sleep and is reacquired afterwards. | |
862 | */ | |
863 | #define wait_event_lock_irq(wq, condition, lock) \ | |
864 | do { \ | |
865 | if (condition) \ | |
866 | break; \ | |
867 | __wait_event_lock_irq(wq, condition, lock, ); \ | |
868 | } while (0) | |
869 | ||
870 | ||
35a2af94 | 871 | #define __wait_event_interruptible_lock_irq(wq, condition, lock, cmd) \ |
fb869b6e | 872 | ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ |
35a2af94 PZ |
873 | spin_unlock_irq(&lock); \ |
874 | cmd; \ | |
875 | schedule(); \ | |
8fbd88fa | 876 | spin_lock_irq(&lock)) |
eed8c02e LC |
877 | |
878 | /** | |
879 | * wait_event_interruptible_lock_irq_cmd - sleep until a condition gets true. | |
880 | * The condition is checked under the lock. This is expected to | |
881 | * be called with the lock taken. | |
882 | * @wq: the waitqueue to wait on | |
883 | * @condition: a C expression for the event to wait for | |
884 | * @lock: a locked spinlock_t, which will be released before cmd and | |
885 | * schedule() and reacquired afterwards. | |
886 | * @cmd: a command which is invoked outside the critical section before | |
887 | * sleep | |
888 | * | |
889 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
890 | * @condition evaluates to true or a signal is received. The @condition is | |
891 | * checked each time the waitqueue @wq is woken up. | |
892 | * | |
893 | * wake_up() has to be called after changing any variable that could | |
894 | * change the result of the wait condition. | |
895 | * | |
896 | * This is supposed to be called while holding the lock. The lock is | |
897 | * dropped before invoking the cmd and going to sleep and is reacquired | |
898 | * afterwards. | |
899 | * | |
900 | * The macro will return -ERESTARTSYS if it was interrupted by a signal | |
901 | * and 0 if @condition evaluated to true. | |
902 | */ | |
903 | #define wait_event_interruptible_lock_irq_cmd(wq, condition, lock, cmd) \ | |
904 | ({ \ | |
905 | int __ret = 0; \ | |
eed8c02e | 906 | if (!(condition)) \ |
fb869b6e | 907 | __ret = __wait_event_interruptible_lock_irq(wq, \ |
35a2af94 | 908 | condition, lock, cmd); \ |
eed8c02e LC |
909 | __ret; \ |
910 | }) | |
911 | ||
912 | /** | |
913 | * wait_event_interruptible_lock_irq - sleep until a condition gets true. | |
914 | * The condition is checked under the lock. This is expected | |
915 | * to be called with the lock taken. | |
916 | * @wq: the waitqueue to wait on | |
917 | * @condition: a C expression for the event to wait for | |
918 | * @lock: a locked spinlock_t, which will be released before schedule() | |
919 | * and reacquired afterwards. | |
920 | * | |
921 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
922 | * @condition evaluates to true or signal is received. The @condition is | |
923 | * checked each time the waitqueue @wq is woken up. | |
924 | * | |
925 | * wake_up() has to be called after changing any variable that could | |
926 | * change the result of the wait condition. | |
927 | * | |
928 | * This is supposed to be called while holding the lock. The lock is | |
929 | * dropped before going to sleep and is reacquired afterwards. | |
930 | * | |
931 | * The macro will return -ERESTARTSYS if it was interrupted by a signal | |
932 | * and 0 if @condition evaluated to true. | |
933 | */ | |
934 | #define wait_event_interruptible_lock_irq(wq, condition, lock) \ | |
935 | ({ \ | |
936 | int __ret = 0; \ | |
eed8c02e | 937 | if (!(condition)) \ |
35a2af94 | 938 | __ret = __wait_event_interruptible_lock_irq(wq, \ |
92ec1180 | 939 | condition, lock,); \ |
eed8c02e LC |
940 | __ret; \ |
941 | }) | |
942 | ||
fb869b6e IM |
943 | #define __wait_event_interruptible_lock_irq_timeout(wq, condition, \ |
944 | lock, timeout) \ | |
35a2af94 | 945 | ___wait_event(wq, ___wait_cond_timeout(condition), \ |
7d716456 | 946 | TASK_INTERRUPTIBLE, 0, timeout, \ |
35a2af94 PZ |
947 | spin_unlock_irq(&lock); \ |
948 | __ret = schedule_timeout(__ret); \ | |
a1dc6852 | 949 | spin_lock_irq(&lock)); |
d79ff142 MP |
950 | |
951 | /** | |
fb869b6e IM |
952 | * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets |
953 | * true or a timeout elapses. The condition is checked under | |
954 | * the lock. This is expected to be called with the lock taken. | |
d79ff142 MP |
955 | * @wq: the waitqueue to wait on |
956 | * @condition: a C expression for the event to wait for | |
957 | * @lock: a locked spinlock_t, which will be released before schedule() | |
958 | * and reacquired afterwards. | |
959 | * @timeout: timeout, in jiffies | |
960 | * | |
961 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | |
962 | * @condition evaluates to true or signal is received. The @condition is | |
963 | * checked each time the waitqueue @wq is woken up. | |
964 | * | |
965 | * wake_up() has to be called after changing any variable that could | |
966 | * change the result of the wait condition. | |
967 | * | |
968 | * This is supposed to be called while holding the lock. The lock is | |
969 | * dropped before going to sleep and is reacquired afterwards. | |
970 | * | |
971 | * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it | |
972 | * was interrupted by a signal, and the remaining jiffies otherwise | |
973 | * if the condition evaluated to true before the timeout elapsed. | |
974 | */ | |
975 | #define wait_event_interruptible_lock_irq_timeout(wq, condition, lock, \ | |
976 | timeout) \ | |
977 | ({ \ | |
35a2af94 | 978 | long __ret = timeout; \ |
8922915b | 979 | if (!___wait_cond_timeout(condition)) \ |
35a2af94 PZ |
980 | __ret = __wait_event_interruptible_lock_irq_timeout( \ |
981 | wq, condition, lock, timeout); \ | |
d79ff142 MP |
982 | __ret; \ |
983 | }) | |
984 | ||
1da177e4 LT |
985 | /* |
986 | * Waitqueues which are removed from the waitqueue_head at wakeup time | |
987 | */ | |
b3c97528 HH |
988 | void prepare_to_wait(wait_queue_head_t *q, wait_queue_t *wait, int state); |
989 | void prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state); | |
c2d81644 | 990 | long prepare_to_wait_event(wait_queue_head_t *q, wait_queue_t *wait, int state); |
b3c97528 | 991 | void finish_wait(wait_queue_head_t *q, wait_queue_t *wait); |
fb869b6e | 992 | void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait, unsigned int mode, void *key); |
61ada528 PZ |
993 | long wait_woken(wait_queue_t *wait, unsigned mode, long timeout); |
994 | int woken_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key); | |
1da177e4 LT |
995 | int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key); |
996 | int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key); | |
997 | ||
bf368e4e | 998 | #define DEFINE_WAIT_FUNC(name, function) \ |
1da177e4 | 999 | wait_queue_t name = { \ |
c43dc2fd | 1000 | .private = current, \ |
bf368e4e | 1001 | .func = function, \ |
7e43c84e | 1002 | .task_list = LIST_HEAD_INIT((name).task_list), \ |
1da177e4 LT |
1003 | } |
1004 | ||
bf368e4e ED |
1005 | #define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function) |
1006 | ||
1da177e4 LT |
1007 | #define DEFINE_WAIT_BIT(name, word, bit) \ |
1008 | struct wait_bit_queue name = { \ | |
1009 | .key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \ | |
1010 | .wait = { \ | |
c43dc2fd | 1011 | .private = current, \ |
1da177e4 LT |
1012 | .func = wake_bit_function, \ |
1013 | .task_list = \ | |
1014 | LIST_HEAD_INIT((name).wait.task_list), \ | |
1015 | }, \ | |
1016 | } | |
1017 | ||
1018 | #define init_wait(wait) \ | |
1019 | do { \ | |
c43dc2fd | 1020 | (wait)->private = current; \ |
1da177e4 LT |
1021 | (wait)->func = autoremove_wake_function; \ |
1022 | INIT_LIST_HEAD(&(wait)->task_list); \ | |
231d0aef | 1023 | (wait)->flags = 0; \ |
1da177e4 LT |
1024 | } while (0) |
1025 | ||
74316201 | 1026 | |
dfd01f02 PZ |
1027 | extern int bit_wait(struct wait_bit_key *, int); |
1028 | extern int bit_wait_io(struct wait_bit_key *, int); | |
1029 | extern int bit_wait_timeout(struct wait_bit_key *, int); | |
1030 | extern int bit_wait_io_timeout(struct wait_bit_key *, int); | |
74316201 | 1031 | |
1da177e4 LT |
1032 | /** |
1033 | * wait_on_bit - wait for a bit to be cleared | |
1034 | * @word: the word being waited on, a kernel virtual address | |
1035 | * @bit: the bit of the word being waited on | |
1da177e4 LT |
1036 | * @mode: the task state to sleep in |
1037 | * | |
1038 | * There is a standard hashed waitqueue table for generic use. This | |
1039 | * is the part of the hashtable's accessor API that waits on a bit. | |
1040 | * For instance, if one were to have waiters on a bitflag, one would | |
1041 | * call wait_on_bit() in threads waiting for the bit to clear. | |
1042 | * One uses wait_on_bit() where one is waiting for the bit to clear, | |
1043 | * but has no intention of setting it. | |
74316201 N |
1044 | * Returned value will be zero if the bit was cleared, or non-zero |
1045 | * if the process received a signal and the mode permitted wakeup | |
1046 | * on that signal. | |
1047 | */ | |
1048 | static inline int | |
7e605987 | 1049 | wait_on_bit(unsigned long *word, int bit, unsigned mode) |
74316201 | 1050 | { |
e22b886a | 1051 | might_sleep(); |
74316201 N |
1052 | if (!test_bit(bit, word)) |
1053 | return 0; | |
1054 | return out_of_line_wait_on_bit(word, bit, | |
1055 | bit_wait, | |
1056 | mode); | |
1057 | } | |
1058 | ||
1059 | /** | |
1060 | * wait_on_bit_io - wait for a bit to be cleared | |
1061 | * @word: the word being waited on, a kernel virtual address | |
1062 | * @bit: the bit of the word being waited on | |
1063 | * @mode: the task state to sleep in | |
1064 | * | |
1065 | * Use the standard hashed waitqueue table to wait for a bit | |
1066 | * to be cleared. This is similar to wait_on_bit(), but calls | |
1067 | * io_schedule() instead of schedule() for the actual waiting. | |
1068 | * | |
1069 | * Returned value will be zero if the bit was cleared, or non-zero | |
1070 | * if the process received a signal and the mode permitted wakeup | |
1071 | * on that signal. | |
1072 | */ | |
1073 | static inline int | |
7e605987 | 1074 | wait_on_bit_io(unsigned long *word, int bit, unsigned mode) |
74316201 | 1075 | { |
e22b886a | 1076 | might_sleep(); |
74316201 N |
1077 | if (!test_bit(bit, word)) |
1078 | return 0; | |
1079 | return out_of_line_wait_on_bit(word, bit, | |
1080 | bit_wait_io, | |
1081 | mode); | |
1082 | } | |
1083 | ||
44fc0e5e JH |
1084 | /** |
1085 | * wait_on_bit_timeout - wait for a bit to be cleared or a timeout elapses | |
1086 | * @word: the word being waited on, a kernel virtual address | |
1087 | * @bit: the bit of the word being waited on | |
1088 | * @mode: the task state to sleep in | |
1089 | * @timeout: timeout, in jiffies | |
1090 | * | |
1091 | * Use the standard hashed waitqueue table to wait for a bit | |
1092 | * to be cleared. This is similar to wait_on_bit(), except also takes a | |
1093 | * timeout parameter. | |
1094 | * | |
1095 | * Returned value will be zero if the bit was cleared before the | |
1096 | * @timeout elapsed, or non-zero if the @timeout elapsed or process | |
1097 | * received a signal and the mode permitted wakeup on that signal. | |
1098 | */ | |
1099 | static inline int | |
7e605987 PD |
1100 | wait_on_bit_timeout(unsigned long *word, int bit, unsigned mode, |
1101 | unsigned long timeout) | |
44fc0e5e JH |
1102 | { |
1103 | might_sleep(); | |
1104 | if (!test_bit(bit, word)) | |
1105 | return 0; | |
1106 | return out_of_line_wait_on_bit_timeout(word, bit, | |
1107 | bit_wait_timeout, | |
1108 | mode, timeout); | |
1109 | } | |
1110 | ||
74316201 N |
1111 | /** |
1112 | * wait_on_bit_action - wait for a bit to be cleared | |
1113 | * @word: the word being waited on, a kernel virtual address | |
1114 | * @bit: the bit of the word being waited on | |
1115 | * @action: the function used to sleep, which may take special actions | |
1116 | * @mode: the task state to sleep in | |
1117 | * | |
1118 | * Use the standard hashed waitqueue table to wait for a bit | |
1119 | * to be cleared, and allow the waiting action to be specified. | |
1120 | * This is like wait_on_bit() but allows fine control of how the waiting | |
1121 | * is done. | |
1122 | * | |
1123 | * Returned value will be zero if the bit was cleared, or non-zero | |
1124 | * if the process received a signal and the mode permitted wakeup | |
1125 | * on that signal. | |
1da177e4 | 1126 | */ |
fb869b6e | 1127 | static inline int |
7e605987 PD |
1128 | wait_on_bit_action(unsigned long *word, int bit, wait_bit_action_f *action, |
1129 | unsigned mode) | |
1da177e4 | 1130 | { |
e22b886a | 1131 | might_sleep(); |
1da177e4 LT |
1132 | if (!test_bit(bit, word)) |
1133 | return 0; | |
1134 | return out_of_line_wait_on_bit(word, bit, action, mode); | |
1135 | } | |
1136 | ||
1137 | /** | |
1138 | * wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it | |
1139 | * @word: the word being waited on, a kernel virtual address | |
1140 | * @bit: the bit of the word being waited on | |
1da177e4 LT |
1141 | * @mode: the task state to sleep in |
1142 | * | |
1143 | * There is a standard hashed waitqueue table for generic use. This | |
1144 | * is the part of the hashtable's accessor API that waits on a bit | |
1145 | * when one intends to set it, for instance, trying to lock bitflags. | |
1146 | * For instance, if one were to have waiters trying to set bitflag | |
1147 | * and waiting for it to clear before setting it, one would call | |
1148 | * wait_on_bit() in threads waiting to be able to set the bit. | |
1149 | * One uses wait_on_bit_lock() where one is waiting for the bit to | |
1150 | * clear with the intention of setting it, and when done, clearing it. | |
74316201 N |
1151 | * |
1152 | * Returns zero if the bit was (eventually) found to be clear and was | |
1153 | * set. Returns non-zero if a signal was delivered to the process and | |
1154 | * the @mode allows that signal to wake the process. | |
1155 | */ | |
1156 | static inline int | |
7e605987 | 1157 | wait_on_bit_lock(unsigned long *word, int bit, unsigned mode) |
74316201 | 1158 | { |
e22b886a | 1159 | might_sleep(); |
74316201 N |
1160 | if (!test_and_set_bit(bit, word)) |
1161 | return 0; | |
1162 | return out_of_line_wait_on_bit_lock(word, bit, bit_wait, mode); | |
1163 | } | |
1164 | ||
1165 | /** | |
1166 | * wait_on_bit_lock_io - wait for a bit to be cleared, when wanting to set it | |
1167 | * @word: the word being waited on, a kernel virtual address | |
1168 | * @bit: the bit of the word being waited on | |
1169 | * @mode: the task state to sleep in | |
1170 | * | |
1171 | * Use the standard hashed waitqueue table to wait for a bit | |
1172 | * to be cleared and then to atomically set it. This is similar | |
1173 | * to wait_on_bit(), but calls io_schedule() instead of schedule() | |
1174 | * for the actual waiting. | |
1175 | * | |
1176 | * Returns zero if the bit was (eventually) found to be clear and was | |
1177 | * set. Returns non-zero if a signal was delivered to the process and | |
1178 | * the @mode allows that signal to wake the process. | |
1179 | */ | |
1180 | static inline int | |
7e605987 | 1181 | wait_on_bit_lock_io(unsigned long *word, int bit, unsigned mode) |
74316201 | 1182 | { |
e22b886a | 1183 | might_sleep(); |
74316201 N |
1184 | if (!test_and_set_bit(bit, word)) |
1185 | return 0; | |
1186 | return out_of_line_wait_on_bit_lock(word, bit, bit_wait_io, mode); | |
1187 | } | |
1188 | ||
1189 | /** | |
1190 | * wait_on_bit_lock_action - wait for a bit to be cleared, when wanting to set it | |
1191 | * @word: the word being waited on, a kernel virtual address | |
1192 | * @bit: the bit of the word being waited on | |
1193 | * @action: the function used to sleep, which may take special actions | |
1194 | * @mode: the task state to sleep in | |
1195 | * | |
1196 | * Use the standard hashed waitqueue table to wait for a bit | |
1197 | * to be cleared and then to set it, and allow the waiting action | |
1198 | * to be specified. | |
1199 | * This is like wait_on_bit() but allows fine control of how the waiting | |
1200 | * is done. | |
1201 | * | |
1202 | * Returns zero if the bit was (eventually) found to be clear and was | |
1203 | * set. Returns non-zero if a signal was delivered to the process and | |
1204 | * the @mode allows that signal to wake the process. | |
1da177e4 | 1205 | */ |
fb869b6e | 1206 | static inline int |
7e605987 PD |
1207 | wait_on_bit_lock_action(unsigned long *word, int bit, wait_bit_action_f *action, |
1208 | unsigned mode) | |
1da177e4 | 1209 | { |
e22b886a | 1210 | might_sleep(); |
1da177e4 LT |
1211 | if (!test_and_set_bit(bit, word)) |
1212 | return 0; | |
1213 | return out_of_line_wait_on_bit_lock(word, bit, action, mode); | |
1214 | } | |
cb65537e DH |
1215 | |
1216 | /** | |
1217 | * wait_on_atomic_t - Wait for an atomic_t to become 0 | |
1218 | * @val: The atomic value being waited on, a kernel virtual address | |
1219 | * @action: the function used to sleep, which may take special actions | |
1220 | * @mode: the task state to sleep in | |
1221 | * | |
1222 | * Wait for an atomic_t to become 0. We abuse the bit-wait waitqueue table for | |
1223 | * the purpose of getting a waitqueue, but we set the key to a bit number | |
1224 | * outside of the target 'word'. | |
1225 | */ | |
1226 | static inline | |
1227 | int wait_on_atomic_t(atomic_t *val, int (*action)(atomic_t *), unsigned mode) | |
1228 | { | |
e22b886a | 1229 | might_sleep(); |
cb65537e DH |
1230 | if (atomic_read(val) == 0) |
1231 | return 0; | |
1232 | return out_of_line_wait_on_atomic_t(val, action, mode); | |
1233 | } | |
fb869b6e IM |
1234 | |
1235 | #endif /* _LINUX_WAIT_H */ |