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_tail(wait_queue_head_t
*head
,
133 list_add_tail(&new->task_list
, &head
->task_list
);
136 static inline void __remove_wait_queue(wait_queue_head_t
*head
,
139 list_del(&old
->task_list
);
142 void __wake_up(wait_queue_head_t
*q
, unsigned int mode
, int nr
, void *key
);
143 void __wake_up_locked_key(wait_queue_head_t
*q
, unsigned int mode
, void *key
);
144 void __wake_up_sync_key(wait_queue_head_t
*q
, unsigned int mode
, int nr
,
146 void __wake_up_locked(wait_queue_head_t
*q
, unsigned int mode
);
147 void __wake_up_sync(wait_queue_head_t
*q
, unsigned int mode
, int nr
);
148 void __wake_up_bit(wait_queue_head_t
*, void *, int);
149 int __wait_on_bit(wait_queue_head_t
*, struct wait_bit_queue
*, int (*)(void *), unsigned);
150 int __wait_on_bit_lock(wait_queue_head_t
*, struct wait_bit_queue
*, int (*)(void *), unsigned);
151 void wake_up_bit(void *, int);
152 int out_of_line_wait_on_bit(void *, int, int (*)(void *), unsigned);
153 int out_of_line_wait_on_bit_lock(void *, int, int (*)(void *), unsigned);
154 wait_queue_head_t
*bit_waitqueue(void *, int);
156 #define wake_up(x) __wake_up(x, TASK_NORMAL, 1, NULL)
157 #define wake_up_nr(x, nr) __wake_up(x, TASK_NORMAL, nr, NULL)
158 #define wake_up_all(x) __wake_up(x, TASK_NORMAL, 0, NULL)
159 #define wake_up_locked(x) __wake_up_locked((x), TASK_NORMAL)
161 #define wake_up_interruptible(x) __wake_up(x, TASK_INTERRUPTIBLE, 1, NULL)
162 #define wake_up_interruptible_nr(x, nr) __wake_up(x, TASK_INTERRUPTIBLE, nr, NULL)
163 #define wake_up_interruptible_all(x) __wake_up(x, TASK_INTERRUPTIBLE, 0, NULL)
164 #define wake_up_interruptible_sync(x) __wake_up_sync((x), TASK_INTERRUPTIBLE, 1)
167 * Wakeup macros to be used to report events to the targets.
169 #define wake_up_poll(x, m) \
170 __wake_up(x, TASK_NORMAL, 1, (void *) (m))
171 #define wake_up_locked_poll(x, m) \
172 __wake_up_locked_key((x), TASK_NORMAL, (void *) (m))
173 #define wake_up_interruptible_poll(x, m) \
174 __wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m))
175 #define wake_up_interruptible_sync_poll(x, m) \
176 __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m))
178 #define __wait_event(wq, condition) \
180 DEFINE_WAIT(__wait); \
183 prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
188 finish_wait(&wq, &__wait); \
192 * wait_event - sleep until a condition gets true
193 * @wq: the waitqueue to wait on
194 * @condition: a C expression for the event to wait for
196 * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
197 * @condition evaluates to true. The @condition is checked each time
198 * the waitqueue @wq is woken up.
200 * wake_up() has to be called after changing any variable that could
201 * change the result of the wait condition.
203 #define wait_event(wq, condition) \
207 __wait_event(wq, condition); \
210 #define __wait_event_timeout(wq, condition, ret) \
212 DEFINE_WAIT(__wait); \
215 prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \
218 ret = schedule_timeout(ret); \
222 finish_wait(&wq, &__wait); \
226 * wait_event_timeout - sleep until a condition gets true or a timeout elapses
227 * @wq: the waitqueue to wait on
228 * @condition: a C expression for the event to wait for
229 * @timeout: timeout, in jiffies
231 * The process is put to sleep (TASK_UNINTERRUPTIBLE) until the
232 * @condition evaluates to true. The @condition is checked each time
233 * the waitqueue @wq is woken up.
235 * wake_up() has to be called after changing any variable that could
236 * change the result of the wait condition.
238 * The function returns 0 if the @timeout elapsed, and the remaining
239 * jiffies if the condition evaluated to true before the timeout elapsed.
241 #define wait_event_timeout(wq, condition, timeout) \
243 long __ret = timeout; \
245 __wait_event_timeout(wq, condition, __ret); \
249 #define __wait_event_interruptible(wq, condition, ret) \
251 DEFINE_WAIT(__wait); \
254 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
257 if (!signal_pending(current)) { \
261 ret = -ERESTARTSYS; \
264 finish_wait(&wq, &__wait); \
268 * wait_event_interruptible - sleep until a condition gets true
269 * @wq: the waitqueue to wait on
270 * @condition: a C expression for the event to wait for
272 * The process is put to sleep (TASK_INTERRUPTIBLE) until the
273 * @condition evaluates to true or a signal is received.
274 * The @condition is checked each time the waitqueue @wq is woken up.
276 * wake_up() has to be called after changing any variable that could
277 * change the result of the wait condition.
279 * The function will return -ERESTARTSYS if it was interrupted by a
280 * signal and 0 if @condition evaluated to true.
282 #define wait_event_interruptible(wq, condition) \
286 __wait_event_interruptible(wq, condition, __ret); \
290 #define __wait_event_interruptible_timeout(wq, condition, ret) \
292 DEFINE_WAIT(__wait); \
295 prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \
298 if (!signal_pending(current)) { \
299 ret = schedule_timeout(ret); \
304 ret = -ERESTARTSYS; \
307 finish_wait(&wq, &__wait); \
311 * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses
312 * @wq: the waitqueue to wait on
313 * @condition: a C expression for the event to wait for
314 * @timeout: timeout, in jiffies
316 * The process is put to sleep (TASK_INTERRUPTIBLE) until the
317 * @condition evaluates to true or a signal is received.
318 * The @condition is checked each time the waitqueue @wq is woken up.
320 * wake_up() has to be called after changing any variable that could
321 * change the result of the wait condition.
323 * The function returns 0 if the @timeout elapsed, -ERESTARTSYS if it
324 * was interrupted by a signal, and the remaining jiffies otherwise
325 * if the condition evaluated to true before the timeout elapsed.
327 #define wait_event_interruptible_timeout(wq, condition, timeout) \
329 long __ret = timeout; \
331 __wait_event_interruptible_timeout(wq, condition, __ret); \
335 #define __wait_event_interruptible_exclusive(wq, condition, ret) \
337 DEFINE_WAIT(__wait); \
340 prepare_to_wait_exclusive(&wq, &__wait, \
341 TASK_INTERRUPTIBLE); \
343 finish_wait(&wq, &__wait); \
346 if (!signal_pending(current)) { \
350 ret = -ERESTARTSYS; \
351 abort_exclusive_wait(&wq, &__wait, \
352 TASK_INTERRUPTIBLE, NULL); \
357 #define wait_event_interruptible_exclusive(wq, condition) \
361 __wait_event_interruptible_exclusive(wq, condition, __ret);\
366 #define __wait_event_interruptible_locked(wq, condition, exclusive, irq) \
369 DEFINE_WAIT(__wait); \
371 __wait.flags |= WQ_FLAG_EXCLUSIVE; \
373 if (likely(list_empty(&__wait.task_list))) \
374 __add_wait_queue_tail(&(wq), &__wait); \
375 set_current_state(TASK_INTERRUPTIBLE); \
376 if (signal_pending(current)) { \
377 __ret = -ERESTARTSYS; \
381 spin_unlock_irq(&(wq).lock); \
383 spin_unlock(&(wq).lock); \
386 spin_lock_irq(&(wq).lock); \
388 spin_lock(&(wq).lock); \
389 } while (!(condition)); \
390 __remove_wait_queue(&(wq), &__wait); \
391 __set_current_state(TASK_RUNNING); \
397 * wait_event_interruptible_locked - sleep until a condition gets true
398 * @wq: the waitqueue to wait on
399 * @condition: a C expression for the event to wait for
401 * The process is put to sleep (TASK_INTERRUPTIBLE) until the
402 * @condition evaluates to true or a signal is received.
403 * The @condition is checked each time the waitqueue @wq is woken up.
405 * It must be called with wq.lock being held. This spinlock is
406 * unlocked while sleeping but @condition testing is done while lock
407 * is held and when this macro exits the lock is held.
409 * The lock is locked/unlocked using spin_lock()/spin_unlock()
410 * functions which must match the way they are locked/unlocked outside
413 * wake_up_locked() has to be called after changing any variable that could
414 * change the result of the wait condition.
416 * The function will return -ERESTARTSYS if it was interrupted by a
417 * signal and 0 if @condition evaluated to true.
419 #define wait_event_interruptible_locked(wq, condition) \
421 ? 0 : __wait_event_interruptible_locked(wq, condition, 0, 0))
424 * wait_event_interruptible_locked_irq - sleep until a condition gets true
425 * @wq: the waitqueue to wait on
426 * @condition: a C expression for the event to wait for
428 * The process is put to sleep (TASK_INTERRUPTIBLE) until the
429 * @condition evaluates to true or a signal is received.
430 * The @condition is checked each time the waitqueue @wq is woken up.
432 * It must be called with wq.lock being held. This spinlock is
433 * unlocked while sleeping but @condition testing is done while lock
434 * is held and when this macro exits the lock is held.
436 * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq()
437 * functions which must match the way they are locked/unlocked outside
440 * wake_up_locked() has to be called after changing any variable that could
441 * change the result of the wait condition.
443 * The function will return -ERESTARTSYS if it was interrupted by a
444 * signal and 0 if @condition evaluated to true.
446 #define wait_event_interruptible_locked_irq(wq, condition) \
448 ? 0 : __wait_event_interruptible_locked(wq, condition, 0, 1))
451 * wait_event_interruptible_exclusive_locked - sleep exclusively until a condition gets true
452 * @wq: the waitqueue to wait on
453 * @condition: a C expression for the event to wait for
455 * The process is put to sleep (TASK_INTERRUPTIBLE) until the
456 * @condition evaluates to true or a signal is received.
457 * The @condition is checked each time the waitqueue @wq is woken up.
459 * It must be called with wq.lock being held. This spinlock is
460 * unlocked while sleeping but @condition testing is done while lock
461 * is held and when this macro exits the lock is held.
463 * The lock is locked/unlocked using spin_lock()/spin_unlock()
464 * functions which must match the way they are locked/unlocked outside
467 * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
468 * set thus when other process waits process on the list if this
469 * process is awaken further processes are not considered.
471 * wake_up_locked() has to be called after changing any variable that could
472 * change the result of the wait condition.
474 * The function will return -ERESTARTSYS if it was interrupted by a
475 * signal and 0 if @condition evaluated to true.
477 #define wait_event_interruptible_exclusive_locked(wq, condition) \
479 ? 0 : __wait_event_interruptible_locked(wq, condition, 1, 0))
482 * wait_event_interruptible_exclusive_locked_irq - sleep until a condition gets true
483 * @wq: the waitqueue to wait on
484 * @condition: a C expression for the event to wait for
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 is woken up.
490 * It must be called with wq.lock being held. This spinlock is
491 * unlocked while sleeping but @condition testing is done while lock
492 * is held and when this macro exits the lock is held.
494 * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq()
495 * functions which must match the way they are locked/unlocked outside
498 * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag
499 * set thus when other process waits process on the list if this
500 * process is awaken further processes are not considered.
502 * wake_up_locked() has to be called after changing any variable that could
503 * change the result of the wait condition.
505 * The function will return -ERESTARTSYS if it was interrupted by a
506 * signal and 0 if @condition evaluated to true.
508 #define wait_event_interruptible_exclusive_locked_irq(wq, condition) \
510 ? 0 : __wait_event_interruptible_locked(wq, condition, 1, 1))
514 #define __wait_event_killable(wq, condition, ret) \
516 DEFINE_WAIT(__wait); \
519 prepare_to_wait(&wq, &__wait, TASK_KILLABLE); \
522 if (!fatal_signal_pending(current)) { \
526 ret = -ERESTARTSYS; \
529 finish_wait(&wq, &__wait); \
533 * wait_event_killable - sleep until a condition gets true
534 * @wq: the waitqueue to wait on
535 * @condition: a C expression for the event to wait for
537 * The process is put to sleep (TASK_KILLABLE) until the
538 * @condition evaluates to true or a signal is received.
539 * The @condition is checked each time the waitqueue @wq is woken up.
541 * wake_up() has to be called after changing any variable that could
542 * change the result of the wait condition.
544 * The function will return -ERESTARTSYS if it was interrupted by a
545 * signal and 0 if @condition evaluated to true.
547 #define wait_event_killable(wq, condition) \
551 __wait_event_killable(wq, condition, __ret); \
556 * Must be called with the spinlock in the wait_queue_head_t held.
558 static inline void add_wait_queue_exclusive_locked(wait_queue_head_t
*q
,
561 wait
->flags
|= WQ_FLAG_EXCLUSIVE
;
562 __add_wait_queue_tail(q
, wait
);
566 * Must be called with the spinlock in the wait_queue_head_t held.
568 static inline void remove_wait_queue_locked(wait_queue_head_t
*q
,
571 __remove_wait_queue(q
, wait
);
575 * These are the old interfaces to sleep waiting for an event.
576 * They are racy. DO NOT use them, use the wait_event* interfaces above.
577 * We plan to remove these interfaces.
579 extern void sleep_on(wait_queue_head_t
*q
);
580 extern long sleep_on_timeout(wait_queue_head_t
*q
,
581 signed long timeout
);
582 extern void interruptible_sleep_on(wait_queue_head_t
*q
);
583 extern long interruptible_sleep_on_timeout(wait_queue_head_t
*q
,
584 signed long timeout
);
587 * Waitqueues which are removed from the waitqueue_head at wakeup time
589 void prepare_to_wait(wait_queue_head_t
*q
, wait_queue_t
*wait
, int state
);
590 void prepare_to_wait_exclusive(wait_queue_head_t
*q
, wait_queue_t
*wait
, int state
);
591 void finish_wait(wait_queue_head_t
*q
, wait_queue_t
*wait
);
592 void abort_exclusive_wait(wait_queue_head_t
*q
, wait_queue_t
*wait
,
593 unsigned int mode
, void *key
);
594 int autoremove_wake_function(wait_queue_t
*wait
, unsigned mode
, int sync
, void *key
);
595 int wake_bit_function(wait_queue_t
*wait
, unsigned mode
, int sync
, void *key
);
597 #define DEFINE_WAIT_FUNC(name, function) \
598 wait_queue_t name = { \
599 .private = current, \
601 .task_list = LIST_HEAD_INIT((name).task_list), \
604 #define DEFINE_WAIT(name) DEFINE_WAIT_FUNC(name, autoremove_wake_function)
606 #define DEFINE_WAIT_BIT(name, word, bit) \
607 struct wait_bit_queue name = { \
608 .key = __WAIT_BIT_KEY_INITIALIZER(word, bit), \
610 .private = current, \
611 .func = wake_bit_function, \
613 LIST_HEAD_INIT((name).wait.task_list), \
617 #define init_wait(wait) \
619 (wait)->private = current; \
620 (wait)->func = autoremove_wake_function; \
621 INIT_LIST_HEAD(&(wait)->task_list); \
625 * wait_on_bit - wait for a bit to be cleared
626 * @word: the word being waited on, a kernel virtual address
627 * @bit: the bit of the word being waited on
628 * @action: the function used to sleep, which may take special actions
629 * @mode: the task state to sleep in
631 * There is a standard hashed waitqueue table for generic use. This
632 * is the part of the hashtable's accessor API that waits on a bit.
633 * For instance, if one were to have waiters on a bitflag, one would
634 * call wait_on_bit() in threads waiting for the bit to clear.
635 * One uses wait_on_bit() where one is waiting for the bit to clear,
636 * but has no intention of setting it.
638 static inline int wait_on_bit(void *word
, int bit
,
639 int (*action
)(void *), unsigned mode
)
641 if (!test_bit(bit
, word
))
643 return out_of_line_wait_on_bit(word
, bit
, action
, mode
);
647 * wait_on_bit_lock - wait for a bit to be cleared, when wanting to set it
648 * @word: the word being waited on, a kernel virtual address
649 * @bit: the bit of the word being waited on
650 * @action: the function used to sleep, which may take special actions
651 * @mode: the task state to sleep in
653 * There is a standard hashed waitqueue table for generic use. This
654 * is the part of the hashtable's accessor API that waits on a bit
655 * when one intends to set it, for instance, trying to lock bitflags.
656 * For instance, if one were to have waiters trying to set bitflag
657 * and waiting for it to clear before setting it, one would call
658 * wait_on_bit() in threads waiting to be able to set the bit.
659 * One uses wait_on_bit_lock() where one is waiting for the bit to
660 * clear with the intention of setting it, and when done, clearing it.
662 static inline int wait_on_bit_lock(void *word
, int bit
,
663 int (*action
)(void *), unsigned mode
)
665 if (!test_and_set_bit(bit
, word
))
667 return out_of_line_wait_on_bit_lock(word
, bit
, action
, mode
);
670 #endif /* __KERNEL__ */