4 #define WNOHANG 0x00000001
5 #define WUNTRACED 0x00000002
6 #define WSTOPPED WUNTRACED
7 #define WEXITED 0x00000004
8 #define WCONTINUED 0x00000008
9 #define WNOWAIT 0x01000000 /* Don't reap, just poll status. */
11 #define __WNOTHREAD 0x20000000 /* Don't wait on children of other threads in this group */
12 #define __WALL 0x40000000 /* Wait on all children, regardless of type */
13 #define __WCLONE 0x80000000 /* Wait only on non-SIGCHLD children */
15 /* First argument to waitid: */
22 #include <linux/list.h>
23 #include <linux/stddef.h>
24 #include <linux/spinlock.h>
25 #include <asm/system.h>
26 #include <asm/current.h>
28 typedef struct __wait_queue wait_queue_t;
29 typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int flags, void *key);
30 int default_wake_function(wait_queue_t *wait, unsigned mode, int flags, void *key);
34 #define WQ_FLAG_EXCLUSIVE 0x01
36 wait_queue_func_t func;
37 struct list_head task_list;
45 struct wait_bit_queue {
46 struct wait_bit_key key;
50 struct __wait_queue_head {
52 struct list_head task_list;
54 typedef struct __wait_queue_head wait_queue_head_t;
59 * Macros for declaration and initialisaton of the datatypes
62 #define __WAITQUEUE_INITIALIZER(name, tsk) { \
64 .func = default_wake_function, \
65 .task_list = { NULL, NULL } }
67 #define DECLARE_WAITQUEUE(name, tsk) \
68 wait_queue_t name = __WAITQUEUE_INITIALIZER(name, tsk)
70 #define __WAIT_QUEUE_HEAD_INITIALIZER(name) { \
71 .lock = __SPIN_LOCK_UNLOCKED(name.lock), \
72 .task_list = { &(name).task_list, &(name).task_list } }
74 #define DECLARE_WAIT_QUEUE_HEAD(name) \
75 wait_queue_head_t name = __WAIT_QUEUE_HEAD_INITIALIZER(name)
77 #define __WAIT_BIT_KEY_INITIALIZER(word, bit) \
78 { .flags = word, .bit_nr = bit, }
80 extern void __init_waitqueue_head(wait_queue_head_t *q, struct lock_class_key *);
82 #define init_waitqueue_head(q) \
84 static struct lock_class_key __key; \
86 __init_waitqueue_head((q), &__key); \
90 # define __WAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
91 ({ init_waitqueue_head(&name); name; })
92 # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) \
93 wait_queue_head_t name = __WAIT_QUEUE_HEAD_INIT_ONSTACK(name)
95 # define DECLARE_WAIT_QUEUE_HEAD_ONSTACK(name) DECLARE_WAIT_QUEUE_HEAD(name)
98 static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p)
102 q->func = default_wake_function;
105 static inline void init_waitqueue_func_entry(wait_queue_t *q,
106 wait_queue_func_t func)
113 static inline int waitqueue_active(wait_queue_head_t *q)
115 return !list_empty(&q->task_list);
118 extern void add_wait_queue(wait_queue_head_t *q, wait_queue_t *wait);
119 extern void add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t *wait);
120 extern void remove_wait_queue(wait_queue_head_t *q, wait_queue_t *wait);
122 static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new)
124 list_add(&new->task_list, &head->task_list);
128 * Used for wake-one threads:
130 static inline void __add_wait_queue_exclusive(wait_queue_head_t *q,
133 wait->flags |= WQ_FLAG_EXCLUSIVE;
134 __add_wait_queue(q, wait);
137 static inline void __add_wait_queue_tail(wait_queue_head_t *head,
140 list_add_tail(&new->task_list, &head->task_list);
143 static inline void __add_wait_queue_tail_exclusive(wait_queue_head_t *q,
146 wait->flags |= WQ_FLAG_EXCLUSIVE;
147 __add_wait_queue_tail(q, wait);
150 static inline void __remove_wait_queue(wait_queue_head_t *head,
153 list_del(&old->task_list);
156 void __wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *key);
157 void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key);
158 void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr,
160 void __wake_up_locked(wait_queue_head_t *q, unsigned int mode);
161 void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr);
162 void __wake_up_bit(wait_queue_head_t *, void *, int);
163 int __wait_on_bit(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned);
164 int __wait_on_bit_lock(wait_queue_head_t *, struct wait_bit_queue *, int (*)(void *), unsigned);
165 void wake_up_bit(void *, int);
166 int out_of_line_wait_on_bit(void *, int, int (*)(void *), unsigned);
167 int out_of_line_wait_on_bit_lock(void *, int, int (*)(void *), unsigned);
168 wait_queue_head_t *bit_waitqueue(void *, int);
170 #define wake_up(x) __wake_up(x, TASK_NORMAL, 1, NULL)
171 #define wake_up_nr(x, nr) __wake_up(x, TASK_NORMAL, nr, NULL)
172 #define wake_up_all(x) __wake_up(x, TASK_NORMAL, 0, NULL)
173 #define wake_up_locked(x) __wake_up_locked((x), TASK_NORMAL)
175 #define wake_up_interruptible(x) __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
176 #define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
177 #define wake_up_interruptible_all(x) __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
178 #define wake_up_interruptible_sync(x) __wake_up_sync((x), TASK_INTERRUPTIBLE, 1)
181 * Wakeup macros to be used to report events to the targets.
183 #define wake_up_poll(x, m) \
184 __wake_up(x, TASK_NORMAL, 1, (void *) (m))
185 #define wake_up_locked_poll(x, m) \
186 __wake_up_locked_key((x), TASK_NORMAL, (void *) (m))
187 #define wake_up_interruptible_poll(x, m) \
188 __wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m))
189 #define wake_up_interruptible_sync_poll(x, m) \
190 __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m))
192 #define __wait_event(wq, condition) \
194 DEFINE_WAIT(__wait); \
197 prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
202 finish_wait(&wq, &__wait); \
206 * wait_event - sleep until a condition gets true
207 * @wq: the waitqueue to wait on
208 * @condition: a C expression for the event to wait for
210 * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
211 * @condition evaluates to true. The @condition is checked each time
212 * the waitqueue @wq is woken up.
214 * wake_up() has to be called after changing any variable that could
215 * change the result of the wait condition.
217 #define wait_event(wq, condition) \
221 __wait_event(wq, condition); \
224 #define __wait_event_timeout(wq, condition, ret) \
226 DEFINE_WAIT(__wait); \
229 prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
232 ret = schedule_timeout(ret); \
236 finish_wait(&wq, &__wait); \
240 * wait_event_timeout - sleep until a condition gets true or a timeout elapses
241 * @wq: the waitqueue to wait on
242 * @condition: a C expression for the event to wait for
243 * @timeout: timeout, in jiffies
245 * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
246 * @condition evaluates to true. The @condition is checked each time
247 * the waitqueue @wq is woken up.
249 * wake_up() has to be called after changing any variable that could
250 * change the result of the wait condition.
252 * The function returns 0 if the @timeout elapsed, and the remaining
253 * jiffies if the condition evaluated to true before the timeout elapsed.
255 #define wait_event_timeout(wq, condition, timeout) \
257 long __ret = timeout; \
259 __wait_event_timeout(wq, condition, __ret); \
263 #define __wait_event_interruptible(wq, condition, ret) \
265 DEFINE_WAIT(__wait); \
268 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
271 if (!signal_pending(current)) { \
275 ret = -ERESTARTSYS; \
278 finish_wait(&wq, &__wait); \
282 * wait_event_interruptible - sleep until a condition gets true
283 * @wq: the waitqueue to wait on
284 * @condition: a C expression for the event to wait for
286 * The process is put to sleep (TASK_INTERRUPTIBLE) until the
287 * @condition evaluates to true or a signal is received.
288 * The @condition is checked each time the waitqueue @wq is woken up.
290 * wake_up() has to be called after changing any variable that could
291 * change the result of the wait condition.
293 * The function will return -ERESTARTSYS if it was interrupted by a
294 * signal and 0 if @condition evaluated to true.
296 #define wait_event_interruptible(wq, condition) \
300 __wait_event_interruptible(wq, condition, __ret); \
304 #define __wait_event_interruptible_timeout(wq, condition, ret) \
306 DEFINE_WAIT(__wait); \
309 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
312 if (!signal_pending(current)) { \
313 ret = schedule_timeout(ret); \
318 ret = -ERESTARTSYS; \
321 finish_wait(&wq, &__wait); \
325 * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
326 * @wq: the waitqueue to wait on
327 * @condition: a C expression for the event to wait for
328 * @timeout: timeout, in jiffies
330 * The process is put to sleep (TASK_INTERRUPTIBLE) until the
331 * @condition evaluates to true or a signal is received.
332 * The @condition is checked each time the waitqueue @wq is woken up.
334 * wake_up() has to be called after changing any variable that could
335 * change the result of the wait condition.
337 * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
338 * was interrupted by a signal, and the remaining jiffies otherwise
339 * if the condition evaluated to true before the timeout elapsed.
341 #define wait_event_interruptible_timeout(wq, condition, timeout) \
343 long __ret = timeout; \
345 __wait_event_interruptible_timeout(wq, condition, __ret); \
349 #define __wait_event_interruptible_exclusive(wq, condition, ret) \
351 DEFINE_WAIT(__wait); \
354 prepare_to_wait_exclusive(&wq, &__wait, \
355 TASK_INTERRUPTIBLE); \
357 finish_wait(&wq, &__wait); \
360 if (!signal_pending(current)) { \
364 ret = -ERESTARTSYS; \
365 abort_exclusive_wait(&wq, &__wait, \
366 TASK_INTERRUPTIBLE, NULL); \
371 #define wait_event_interruptible_exclusive(wq, condition) \
375 __wait_event_interruptible_exclusive(wq, condition, __ret);\
379 #define __wait_event_killable(wq, condition, ret) \
381 DEFINE_WAIT(__wait); \
384 prepare_to_wait(&wq, &__wait, TASK_KILLABLE); \
387 if (!fatal_signal_pending(current)) { \
391 ret = -ERESTARTSYS; \
394 finish_wait(&wq, &__wait); \
398 * wait_event_killable - sleep until a condition gets true
399 * @wq: the waitqueue to wait on
400 * @condition: a C expression for the event to wait for
402 * The process is put to sleep (TASK_KILLABLE) until the
403 * @condition evaluates to true or a signal is received.
404 * The @condition is checked each time the waitqueue @wq is woken up.
406 * wake_up() has to be called after changing any variable that could
407 * change the result of the wait condition.
409 * The function will return -ERESTARTSYS if it was interrupted by a
410 * signal and 0 if @condition evaluated to true.
412 #define wait_event_killable(wq, condition) \
416 __wait_event_killable(wq, condition, __ret); \
421 * These are the old interfaces to sleep waiting for an event.
422 * They are racy. DO NOT use them, use the wait_event* interfaces above.
423 * We plan to remove these interfaces.
425 extern void sleep_on(wait_queue_head_t *q);
426 extern long sleep_on_timeout(wait_queue_head_t *q,
427 signed long timeout);
428 extern void interruptible_sleep_on(wait_queue_head_t *q);
429 extern long interruptible_sleep_on_timeout(wait_queue_head_t *q,
430 signed long timeout);
433 * Waitqueues which are removed from the waitqueue_head at wakeup time
435 void prepare_to_wait(wait_queue_head_t *q, wait_queue_t *wait, int state);
436 void prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state);
437 void finish_wait(wait_queue_head_t *q, wait_queue_t *wait);
438 void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait,
439 unsigned int mode, void *key);
440 int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
441 int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key);
443 #define DEFINE_WAIT_FUNC(name, function) \
444 wait_queue_t name = { \
445 .private = current, \
447 .task_list = LIST_HEAD_INIT((name).task_list), \
450 #define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function)
452 #define DEFINE_WAIT_BIT(name, word, bit) \
453 struct wait_bit_queue name = { \
454 .key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \
456 .private = current, \
457 .func = wake_bit_function, \
459 LIST_HEAD_INIT((name).wait.task_list), \
463 #define init_wait(wait) \
465 (wait)->private = current; \
466 (wait)->func = autoremove_wake_function; \
467 INIT_LIST_HEAD(&(wait)->task_list); \
471 * wait_on_bit - wait for a bit to be cleared
472 * @word: the word being waited on, a kernel virtual address
473 * @bit: the bit of the word being waited on
474 * @action: the function used to sleep, which may take special actions
475 * @mode: the task state to sleep in
477 * There is a standard hashed waitqueue table for generic use. This
478 * is the part of the hashtable's accessor API that waits on a bit.
479 * For instance, if one were to have waiters on a bitflag, one would
480 * call wait_on_bit() in threads waiting for the bit to clear.
481 * One uses wait_on_bit() where one is waiting for the bit to clear,
482 * but has no intention of setting it.
484 static inline int wait_on_bit(void *word, int bit,
485 int (*action)(void *), unsigned mode)
487 if (!test_bit(bit, word))
489 return out_of_line_wait_on_bit(word, bit, action, mode);
493 * wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it
494 * @word: the word being waited on, a kernel virtual address
495 * @bit: the bit of the word being waited on
496 * @action: the function used to sleep, which may take special actions
497 * @mode: the task state to sleep in
499 * There is a standard hashed waitqueue table for generic use. This
500 * is the part of the hashtable's accessor API that waits on a bit
501 * when one intends to set it, for instance, trying to lock bitflags.
502 * For instance, if one were to have waiters trying to set bitflag
503 * and waiting for it to clear before setting it, one would call
504 * wait_on_bit() in threads waiting to be able to set the bit.
505 * One uses wait_on_bit_lock() where one is waiting for the bit to
506 * clear with the intention of setting it, and when done, clearing it.
508 static inline int wait_on_bit_lock(void *word, int bit,
509 int (*action)(void *), unsigned mode)
511 if (!test_and_set_bit(bit, word))
513 return out_of_line_wait_on_bit_lock(word, bit, action, mode);
516 #endif /* __KERNEL__ */