diff options
Diffstat (limited to 'include/linux/wait.h')
| -rw-r--r-- | include/linux/wait.h | 185 |
1 files changed, 165 insertions, 20 deletions
diff --git a/include/linux/wait.h b/include/linux/wait.h index a48e16b77d5e..3efc9f3f43a0 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h | |||
| @@ -127,12 +127,26 @@ static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new) | |||
| 127 | /* | 127 | /* |
| 128 | * Used for wake-one threads: | 128 | * Used for wake-one threads: |
| 129 | */ | 129 | */ |
| 130 | static inline void __add_wait_queue_exclusive(wait_queue_head_t *q, | ||
| 131 | wait_queue_t *wait) | ||
| 132 | { | ||
| 133 | wait->flags |= WQ_FLAG_EXCLUSIVE; | ||
| 134 | __add_wait_queue(q, wait); | ||
| 135 | } | ||
| 136 | |||
| 130 | static inline void __add_wait_queue_tail(wait_queue_head_t *head, | 137 | static inline void __add_wait_queue_tail(wait_queue_head_t *head, |
| 131 | wait_queue_t *new) | 138 | wait_queue_t *new) |
| 132 | { | 139 | { |
| 133 | list_add_tail(&new->task_list, &head->task_list); | 140 | list_add_tail(&new->task_list, &head->task_list); |
| 134 | } | 141 | } |
| 135 | 142 | ||
| 143 | static inline void __add_wait_queue_tail_exclusive(wait_queue_head_t *q, | ||
| 144 | wait_queue_t *wait) | ||
| 145 | { | ||
| 146 | wait->flags |= WQ_FLAG_EXCLUSIVE; | ||
| 147 | __add_wait_queue_tail(q, wait); | ||
| 148 | } | ||
| 149 | |||
| 136 | static inline void __remove_wait_queue(wait_queue_head_t *head, | 150 | static inline void __remove_wait_queue(wait_queue_head_t *head, |
| 137 | wait_queue_t *old) | 151 | wait_queue_t *old) |
| 138 | { | 152 | { |
| @@ -362,6 +376,155 @@ do { \ | |||
| 362 | __ret; \ | 376 | __ret; \ |
| 363 | }) | 377 | }) |
| 364 | 378 | ||
| 379 | |||
| 380 | #define __wait_event_interruptible_locked(wq, condition, exclusive, irq) \ | ||
| 381 | ({ \ | ||
| 382 | int __ret = 0; \ | ||
| 383 | DEFINE_WAIT(__wait); \ | ||
| 384 | if (exclusive) \ | ||
| 385 | __wait.flags |= WQ_FLAG_EXCLUSIVE; \ | ||
| 386 | do { \ | ||
| 387 | if (likely(list_empty(&__wait.task_list))) \ | ||
| 388 | __add_wait_queue_tail(&(wq), &__wait); \ | ||
| 389 | set_current_state(TASK_INTERRUPTIBLE); \ | ||
| 390 | if (signal_pending(current)) { \ | ||
| 391 | __ret = -ERESTARTSYS; \ | ||
| 392 | break; \ | ||
| 393 | } \ | ||
| 394 | if (irq) \ | ||
| 395 | spin_unlock_irq(&(wq).lock); \ | ||
| 396 | else \ | ||
| 397 | spin_unlock(&(wq).lock); \ | ||
| 398 | schedule(); \ | ||
| 399 | if (irq) \ | ||
| 400 | spin_lock_irq(&(wq).lock); \ | ||
| 401 | else \ | ||
| 402 | spin_lock(&(wq).lock); \ | ||
| 403 | } while (!(condition)); \ | ||
| 404 | __remove_wait_queue(&(wq), &__wait); \ | ||
| 405 | __set_current_state(TASK_RUNNING); \ | ||
| 406 | __ret; \ | ||
| 407 | }) | ||
| 408 | |||
| 409 | |||
| 410 | /** | ||
| 411 | * wait_event_interruptible_locked - sleep until a condition gets true | ||
| 412 | * @wq: the waitqueue to wait on | ||
| 413 | * @condition: a C expression for the event to wait for | ||
| 414 | * | ||
| 415 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | ||
| 416 | * @condition evaluates to true or a signal is received. | ||
| 417 | * The @condition is checked each time the waitqueue @wq is woken up. | ||
| 418 | * | ||
| 419 | * It must be called with wq.lock being held. This spinlock is | ||
| 420 | * unlocked while sleeping but @condition testing is done while lock | ||
| 421 | * is held and when this macro exits the lock is held. | ||
| 422 | * | ||
| 423 | * The lock is locked/unlocked using spin_lock()/spin_unlock() | ||
| 424 | * functions which must match the way they are locked/unlocked outside | ||
| 425 | * of this macro. | ||
| 426 | * | ||
| 427 | * wake_up_locked() has to be called after changing any variable that could | ||
| 428 | * change the result of the wait condition. | ||
| 429 | * | ||
| 430 | * The function will return -ERESTARTSYS if it was interrupted by a | ||
| 431 | * signal and 0 if @condition evaluated to true. | ||
| 432 | */ | ||
| 433 | #define wait_event_interruptible_locked(wq, condition) \ | ||
| 434 | ((condition) \ | ||
| 435 | ? 0 : __wait_event_interruptible_locked(wq, condition, 0, 0)) | ||
| 436 | |||
| 437 | /** | ||
| 438 | * wait_event_interruptible_locked_irq - sleep until a condition gets true | ||
| 439 | * @wq: the waitqueue to wait on | ||
| 440 | * @condition: a C expression for the event to wait for | ||
| 441 | * | ||
| 442 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | ||
| 443 | * @condition evaluates to true or a signal is received. | ||
| 444 | * The @condition is checked each time the waitqueue @wq is woken up. | ||
| 445 | * | ||
| 446 | * It must be called with wq.lock being held. This spinlock is | ||
| 447 | * unlocked while sleeping but @condition testing is done while lock | ||
| 448 | * is held and when this macro exits the lock is held. | ||
| 449 | * | ||
| 450 | * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq() | ||
| 451 | * functions which must match the way they are locked/unlocked outside | ||
| 452 | * of this macro. | ||
| 453 | * | ||
| 454 | * wake_up_locked() has to be called after changing any variable that could | ||
| 455 | * change the result of the wait condition. | ||
| 456 | * | ||
| 457 | * The function will return -ERESTARTSYS if it was interrupted by a | ||
| 458 | * signal and 0 if @condition evaluated to true. | ||
| 459 | */ | ||
| 460 | #define wait_event_interruptible_locked_irq(wq, condition) \ | ||
| 461 | ((condition) \ | ||
| 462 | ? 0 : __wait_event_interruptible_locked(wq, condition, 0, 1)) | ||
| 463 | |||
| 464 | /** | ||
| 465 | * wait_event_interruptible_exclusive_locked - sleep exclusively until a condition gets true | ||
| 466 | * @wq: the waitqueue to wait on | ||
| 467 | * @condition: a C expression for the event to wait for | ||
| 468 | * | ||
| 469 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | ||
| 470 | * @condition evaluates to true or a signal is received. | ||
| 471 | * The @condition is checked each time the waitqueue @wq is woken up. | ||
| 472 | * | ||
| 473 | * It must be called with wq.lock being held. This spinlock is | ||
| 474 | * unlocked while sleeping but @condition testing is done while lock | ||
| 475 | * is held and when this macro exits the lock is held. | ||
| 476 | * | ||
| 477 | * The lock is locked/unlocked using spin_lock()/spin_unlock() | ||
| 478 | * functions which must match the way they are locked/unlocked outside | ||
| 479 | * of this macro. | ||
| 480 | * | ||
| 481 | * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag | ||
| 482 | * set thus when other process waits process on the list if this | ||
| 483 | * process is awaken further processes are not considered. | ||
| 484 | * | ||
| 485 | * wake_up_locked() has to be called after changing any variable that could | ||
| 486 | * change the result of the wait condition. | ||
| 487 | * | ||
| 488 | * The function will return -ERESTARTSYS if it was interrupted by a | ||
| 489 | * signal and 0 if @condition evaluated to true. | ||
| 490 | */ | ||
| 491 | #define wait_event_interruptible_exclusive_locked(wq, condition) \ | ||
| 492 | ((condition) \ | ||
| 493 | ? 0 : __wait_event_interruptible_locked(wq, condition, 1, 0)) | ||
| 494 | |||
| 495 | /** | ||
| 496 | * wait_event_interruptible_exclusive_locked_irq - sleep until a condition gets true | ||
| 497 | * @wq: the waitqueue to wait on | ||
| 498 | * @condition: a C expression for the event to wait for | ||
| 499 | * | ||
| 500 | * The process is put to sleep (TASK_INTERRUPTIBLE) until the | ||
| 501 | * @condition evaluates to true or a signal is received. | ||
| 502 | * The @condition is checked each time the waitqueue @wq is woken up. | ||
| 503 | * | ||
| 504 | * It must be called with wq.lock being held. This spinlock is | ||
| 505 | * unlocked while sleeping but @condition testing is done while lock | ||
| 506 | * is held and when this macro exits the lock is held. | ||
| 507 | * | ||
| 508 | * The lock is locked/unlocked using spin_lock_irq()/spin_unlock_irq() | ||
| 509 | * functions which must match the way they are locked/unlocked outside | ||
| 510 | * of this macro. | ||
| 511 | * | ||
| 512 | * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag | ||
| 513 | * set thus when other process waits process on the list if this | ||
| 514 | * process is awaken further processes are not considered. | ||
| 515 | * | ||
| 516 | * wake_up_locked() has to be called after changing any variable that could | ||
| 517 | * change the result of the wait condition. | ||
| 518 | * | ||
| 519 | * The function will return -ERESTARTSYS if it was interrupted by a | ||
| 520 | * signal and 0 if @condition evaluated to true. | ||
| 521 | */ | ||
| 522 | #define wait_event_interruptible_exclusive_locked_irq(wq, condition) \ | ||
| 523 | ((condition) \ | ||
| 524 | ? 0 : __wait_event_interruptible_locked(wq, condition, 1, 1)) | ||
| 525 | |||
| 526 | |||
| 527 | |||
| 365 | #define __wait_event_killable(wq, condition, ret) \ | 528 | #define __wait_event_killable(wq, condition, ret) \ |
| 366 | do { \ | 529 | do { \ |
| 367 | DEFINE_WAIT(__wait); \ | 530 | DEFINE_WAIT(__wait); \ |
| @@ -404,25 +567,6 @@ do { \ | |||
| 404 | }) | 567 | }) |
| 405 | 568 | ||
| 406 | /* | 569 | /* |
| 407 | * Must be called with the spinlock in the wait_queue_head_t held. | ||
| 408 | */ | ||
| 409 | static inline void add_wait_queue_exclusive_locked(wait_queue_head_t *q, | ||
| 410 | wait_queue_t * wait) | ||
| 411 | { | ||
| 412 | wait->flags |= WQ_FLAG_EXCLUSIVE; | ||
| 413 | __add_wait_queue_tail(q, wait); | ||
| 414 | } | ||
| 415 | |||
| 416 | /* | ||
| 417 | * Must be called with the spinlock in the wait_queue_head_t held. | ||
| 418 | */ | ||
| 419 | static inline void remove_wait_queue_locked(wait_queue_head_t *q, | ||
| 420 | wait_queue_t * wait) | ||
| 421 | { | ||
| 422 | __remove_wait_queue(q, wait); | ||
| 423 | } | ||
| 424 | |||
| 425 | /* | ||
| 426 | * These are the old interfaces to sleep waiting for an event. | 570 | * These are the old interfaces to sleep waiting for an event. |
| 427 | * They are racy. DO NOT use them, use the wait_event* interfaces above. | 571 | * They are racy. DO NOT use them, use the wait_event* interfaces above. |
| 428 | * We plan to remove these interfaces. | 572 | * We plan to remove these interfaces. |
| @@ -470,6 +614,7 @@ int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key); | |||
| 470 | (wait)->private = current; \ | 614 | (wait)->private = current; \ |
| 471 | (wait)->func = autoremove_wake_function; \ | 615 | (wait)->func = autoremove_wake_function; \ |
| 472 | INIT_LIST_HEAD(&(wait)->task_list); \ | 616 | INIT_LIST_HEAD(&(wait)->task_list); \ |
| 617 | (wait)->flags = 0; \ | ||
| 473 | } while (0) | 618 | } while (0) |
| 474 | 619 | ||
| 475 | /** | 620 | /** |
