diff options
Diffstat (limited to 'include/linux/wait.h')
-rw-r--r-- | include/linux/wait.h | 374 |
1 files changed, 141 insertions, 233 deletions
diff --git a/include/linux/wait.h b/include/linux/wait.h index a67fc1635592..3b23afa04d6b 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -1,7 +1,8 @@ #ifndef _LINUX_WAIT_H #define _LINUX_WAIT_H - - +/* + * Linux wait queue related types and methods + */ #include <linux/list.h> #include <linux/stddef.h> #include <linux/spinlock.h> @@ -13,27 +14,27 @@ typedef int (*wait_queue_func_t)(wait_queue_t *wait, unsigned mode, int flags, v int default_wake_function(wait_queue_t *wait, unsigned mode, int flags, void *key); struct __wait_queue { - unsigned int flags; + unsigned int flags; #define WQ_FLAG_EXCLUSIVE 0x01 - void *private; - wait_queue_func_t func; - struct list_head task_list; + void *private; + wait_queue_func_t func; + struct list_head task_list; }; struct wait_bit_key { - void *flags; - int bit_nr; -#define WAIT_ATOMIC_T_BIT_NR -1 + void *flags; + int bit_nr; +#define WAIT_ATOMIC_T_BIT_NR -1 }; struct wait_bit_queue { - struct wait_bit_key key; - wait_queue_t wait; + struct wait_bit_key key; + wait_queue_t wait; }; struct __wait_queue_head { - spinlock_t lock; - struct list_head task_list; + spinlock_t lock; + struct list_head task_list; }; typedef struct __wait_queue_head wait_queue_head_t; @@ -84,17 +85,17 @@ extern void __init_waitqueue_head(wait_queue_head_t *q, const char *name, struct static inline void init_waitqueue_entry(wait_queue_t *q, struct task_struct *p) { - q->flags = 0; - q->private = p; - q->func = default_wake_function; + q->flags = 0; + q->private = p; + q->func = default_wake_function; } -static inline void init_waitqueue_func_entry(wait_queue_t *q, - wait_queue_func_t func) +static inline void +init_waitqueue_func_entry(wait_queue_t *q, wait_queue_func_t func) { - q->flags = 0; - q->private = NULL; - q->func = func; + q->flags = 0; + q->private = NULL; + q->func = func; } static inline int waitqueue_active(wait_queue_head_t *q) @@ -114,8 +115,8 @@ static inline void __add_wait_queue(wait_queue_head_t *head, wait_queue_t *new) /* * Used for wake-one threads: */ -static inline void __add_wait_queue_exclusive(wait_queue_head_t *q, - wait_queue_t *wait) +static inline void +__add_wait_queue_exclusive(wait_queue_head_t *q, wait_queue_t *wait) { wait->flags |= WQ_FLAG_EXCLUSIVE; __add_wait_queue(q, wait); @@ -127,23 +128,22 @@ static inline void __add_wait_queue_tail(wait_queue_head_t *head, list_add_tail(&new->task_list, &head->task_list); } -static inline void __add_wait_queue_tail_exclusive(wait_queue_head_t *q, - wait_queue_t *wait) +static inline void +__add_wait_queue_tail_exclusive(wait_queue_head_t *q, wait_queue_t *wait) { wait->flags |= WQ_FLAG_EXCLUSIVE; __add_wait_queue_tail(q, wait); } -static inline void __remove_wait_queue(wait_queue_head_t *head, - wait_queue_t *old) +static inline void +__remove_wait_queue(wait_queue_head_t *head, wait_queue_t *old) { list_del(&old->task_list); } void __wake_up(wait_queue_head_t *q, unsigned int mode, int nr, void *key); void __wake_up_locked_key(wait_queue_head_t *q, unsigned int mode, void *key); -void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr, - void *key); +void __wake_up_sync_key(wait_queue_head_t *q, unsigned int mode, int nr, void *key); void __wake_up_locked(wait_queue_head_t *q, unsigned int mode, int nr); void __wake_up_sync(wait_queue_head_t *q, unsigned int mode, int nr); void __wake_up_bit(wait_queue_head_t *, void *, int); @@ -170,27 +170,64 @@ wait_queue_head_t *bit_waitqueue(void *, int); /* * Wakeup macros to be used to report events to the targets. */ -#define wake_up_poll(x, m) \ +#define wake_up_poll(x, m) \ __wake_up(x, TASK_NORMAL, 1, (void *) (m)) -#define wake_up_locked_poll(x, m) \ +#define wake_up_locked_poll(x, m) \ __wake_up_locked_key((x), TASK_NORMAL, (void *) (m)) -#define wake_up_interruptible_poll(x, m) \ +#define wake_up_interruptible_poll(x, m) \ __wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m)) #define wake_up_interruptible_sync_poll(x, m) \ __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m)) -#define __wait_event(wq, condition) \ -do { \ - DEFINE_WAIT(__wait); \ +#define ___wait_cond_timeout(condition) \ +({ \ + bool __cond = (condition); \ + if (__cond && !__ret) \ + __ret = 1; \ + __cond || !__ret; \ +}) + +#define ___wait_is_interruptible(state) \ + (!__builtin_constant_p(state) || \ + state == TASK_INTERRUPTIBLE || state == TASK_KILLABLE) \ + +#define ___wait_event(wq, condition, state, exclusive, ret, cmd) \ +({ \ + __label__ __out; \ + wait_queue_t __wait; \ + long __ret = ret; \ + \ + INIT_LIST_HEAD(&__wait.task_list); \ + if (exclusive) \ + __wait.flags = WQ_FLAG_EXCLUSIVE; \ + else \ + __wait.flags = 0; \ \ for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ + long __int = prepare_to_wait_event(&wq, &__wait, state);\ + \ if (condition) \ break; \ - schedule(); \ + \ + if (___wait_is_interruptible(state) && __int) { \ + __ret = __int; \ + if (exclusive) { \ + abort_exclusive_wait(&wq, &__wait, \ + state, NULL); \ + goto __out; \ + } \ + break; \ + } \ + \ + cmd; \ } \ finish_wait(&wq, &__wait); \ -} while (0) +__out: __ret; \ +}) + +#define __wait_event(wq, condition) \ + (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ + schedule()) /** * wait_event - sleep until a condition gets true @@ -204,29 +241,17 @@ do { \ * wake_up() has to be called after changing any variable that could * change the result of the wait condition. */ -#define wait_event(wq, condition) \ +#define wait_event(wq, condition) \ do { \ - if (condition) \ + if (condition) \ break; \ __wait_event(wq, condition); \ } while (0) -#define __wait_event_timeout(wq, condition, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ - if (condition) \ - break; \ - ret = schedule_timeout(ret); \ - if (!ret) \ - break; \ - } \ - if (!ret && (condition)) \ - ret = 1; \ - finish_wait(&wq, &__wait); \ -} while (0) +#define __wait_event_timeout(wq, condition, timeout) \ + ___wait_event(wq, ___wait_cond_timeout(condition), \ + TASK_UNINTERRUPTIBLE, 0, timeout, \ + __ret = schedule_timeout(__ret)) /** * wait_event_timeout - sleep until a condition gets true or a timeout elapses @@ -248,28 +273,14 @@ do { \ #define wait_event_timeout(wq, condition, timeout) \ ({ \ long __ret = timeout; \ - if (!(condition)) \ - __wait_event_timeout(wq, condition, __ret); \ + if (!___wait_cond_timeout(condition)) \ + __ret = __wait_event_timeout(wq, condition, timeout); \ __ret; \ }) -#define __wait_event_interruptible(wq, condition, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ - if (condition) \ - break; \ - if (!signal_pending(current)) { \ - schedule(); \ - continue; \ - } \ - ret = -ERESTARTSYS; \ - break; \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) +#define __wait_event_interruptible(wq, condition) \ + ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ + schedule()) /** * wait_event_interruptible - sleep until a condition gets true @@ -290,31 +301,14 @@ do { \ ({ \ int __ret = 0; \ if (!(condition)) \ - __wait_event_interruptible(wq, condition, __ret); \ + __ret = __wait_event_interruptible(wq, condition); \ __ret; \ }) -#define __wait_event_interruptible_timeout(wq, condition, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ - if (condition) \ - break; \ - if (!signal_pending(current)) { \ - ret = schedule_timeout(ret); \ - if (!ret) \ - break; \ - continue; \ - } \ - ret = -ERESTARTSYS; \ - break; \ - } \ - if (!ret && (condition)) \ - ret = 1; \ - finish_wait(&wq, &__wait); \ -} while (0) +#define __wait_event_interruptible_timeout(wq, condition, timeout) \ + ___wait_event(wq, ___wait_cond_timeout(condition), \ + TASK_INTERRUPTIBLE, 0, timeout, \ + __ret = schedule_timeout(__ret)) /** * wait_event_interruptible_timeout - sleep until a condition gets true or a timeout elapses @@ -337,15 +331,15 @@ do { \ #define wait_event_interruptible_timeout(wq, condition, timeout) \ ({ \ long __ret = timeout; \ - if (!(condition)) \ - __wait_event_interruptible_timeout(wq, condition, __ret); \ + if (!___wait_cond_timeout(condition)) \ + __ret = __wait_event_interruptible_timeout(wq, \ + condition, timeout); \ __ret; \ }) #define __wait_event_hrtimeout(wq, condition, timeout, state) \ ({ \ int __ret = 0; \ - DEFINE_WAIT(__wait); \ struct hrtimer_sleeper __t; \ \ hrtimer_init_on_stack(&__t.timer, CLOCK_MONOTONIC, \ @@ -356,25 +350,15 @@ do { \ current->timer_slack_ns, \ HRTIMER_MODE_REL); \ \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, state); \ - if (condition) \ - break; \ - if (state == TASK_INTERRUPTIBLE && \ - signal_pending(current)) { \ - __ret = -ERESTARTSYS; \ - break; \ - } \ + __ret = ___wait_event(wq, condition, state, 0, 0, \ if (!__t.task) { \ __ret = -ETIME; \ break; \ } \ - schedule(); \ - } \ + schedule()); \ \ hrtimer_cancel(&__t.timer); \ destroy_hrtimer_on_stack(&__t.timer); \ - finish_wait(&wq, &__wait); \ __ret; \ }) @@ -428,33 +412,15 @@ do { \ __ret; \ }) -#define __wait_event_interruptible_exclusive(wq, condition, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait_exclusive(&wq, &__wait, \ - TASK_INTERRUPTIBLE); \ - if (condition) { \ - finish_wait(&wq, &__wait); \ - break; \ - } \ - if (!signal_pending(current)) { \ - schedule(); \ - continue; \ - } \ - ret = -ERESTARTSYS; \ - abort_exclusive_wait(&wq, &__wait, \ - TASK_INTERRUPTIBLE, NULL); \ - break; \ - } \ -} while (0) +#define __wait_event_interruptible_exclusive(wq, condition) \ + ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 1, 0, \ + schedule()) #define wait_event_interruptible_exclusive(wq, condition) \ ({ \ int __ret = 0; \ if (!(condition)) \ - __wait_event_interruptible_exclusive(wq, condition, __ret);\ + __ret = __wait_event_interruptible_exclusive(wq, condition);\ __ret; \ }) @@ -606,24 +572,8 @@ do { \ ? 0 : __wait_event_interruptible_locked(wq, condition, 1, 1)) - -#define __wait_event_killable(wq, condition, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_KILLABLE); \ - if (condition) \ - break; \ - if (!fatal_signal_pending(current)) { \ - schedule(); \ - continue; \ - } \ - ret = -ERESTARTSYS; \ - break; \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) +#define __wait_event_killable(wq, condition) \ + ___wait_event(wq, condition, TASK_KILLABLE, 0, 0, schedule()) /** * wait_event_killable - sleep until a condition gets true @@ -644,26 +594,17 @@ do { \ ({ \ int __ret = 0; \ if (!(condition)) \ - __wait_event_killable(wq, condition, __ret); \ + __ret = __wait_event_killable(wq, condition); \ __ret; \ }) #define __wait_event_lock_irq(wq, condition, lock, cmd) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_UNINTERRUPTIBLE); \ - if (condition) \ - break; \ - spin_unlock_irq(&lock); \ - cmd; \ - schedule(); \ - spin_lock_irq(&lock); \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) + (void)___wait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, 0, \ + spin_unlock_irq(&lock); \ + cmd; \ + schedule(); \ + spin_lock_irq(&lock)) /** * wait_event_lock_irq_cmd - sleep until a condition gets true. The @@ -723,26 +664,12 @@ do { \ } while (0) -#define __wait_event_interruptible_lock_irq(wq, condition, \ - lock, ret, cmd) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ - if (condition) \ - break; \ - if (signal_pending(current)) { \ - ret = -ERESTARTSYS; \ - break; \ - } \ - spin_unlock_irq(&lock); \ - cmd; \ - schedule(); \ - spin_lock_irq(&lock); \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) +#define __wait_event_interruptible_lock_irq(wq, condition, lock, cmd) \ + ___wait_event(wq, condition, TASK_INTERRUPTIBLE, 0, 0, \ + spin_unlock_irq(&lock); \ + cmd; \ + schedule(); \ + spin_lock_irq(&lock)) /** * wait_event_interruptible_lock_irq_cmd - sleep until a condition gets true. @@ -772,10 +699,9 @@ do { \ #define wait_event_interruptible_lock_irq_cmd(wq, condition, lock, cmd) \ ({ \ int __ret = 0; \ - \ if (!(condition)) \ - __wait_event_interruptible_lock_irq(wq, condition, \ - lock, __ret, cmd); \ + __ret = __wait_event_interruptible_lock_irq(wq, \ + condition, lock, cmd); \ __ret; \ }) @@ -804,39 +730,24 @@ do { \ #define wait_event_interruptible_lock_irq(wq, condition, lock) \ ({ \ int __ret = 0; \ - \ if (!(condition)) \ - __wait_event_interruptible_lock_irq(wq, condition, \ - lock, __ret, ); \ + __ret = __wait_event_interruptible_lock_irq(wq, \ + condition, lock,); \ __ret; \ }) #define __wait_event_interruptible_lock_irq_timeout(wq, condition, \ - lock, ret) \ -do { \ - DEFINE_WAIT(__wait); \ - \ - for (;;) { \ - prepare_to_wait(&wq, &__wait, TASK_INTERRUPTIBLE); \ - if (condition) \ - break; \ - if (signal_pending(current)) { \ - ret = -ERESTARTSYS; \ - break; \ - } \ - spin_unlock_irq(&lock); \ - ret = schedule_timeout(ret); \ - spin_lock_irq(&lock); \ - if (!ret) \ - break; \ - } \ - finish_wait(&wq, &__wait); \ -} while (0) + lock, timeout) \ + ___wait_event(wq, ___wait_cond_timeout(condition), \ + TASK_INTERRUPTIBLE, 0, ret, \ + spin_unlock_irq(&lock); \ + __ret = schedule_timeout(__ret); \ + spin_lock_irq(&lock)); /** - * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets true or a timeout elapses. - * The condition is checked under the lock. This is expected - * to be called with the lock taken. + * wait_event_interruptible_lock_irq_timeout - sleep until a condition gets + * true or a timeout elapses. The condition is checked under + * the lock. This is expected to be called with the lock taken. * @wq: the waitqueue to wait on * @condition: a C expression for the event to wait for * @lock: a locked spinlock_t, which will be released before schedule() @@ -860,11 +771,10 @@ do { \ #define wait_event_interruptible_lock_irq_timeout(wq, condition, lock, \ timeout) \ ({ \ - int __ret = timeout; \ - \ - if (!(condition)) \ - __wait_event_interruptible_lock_irq_timeout( \ - wq, condition, lock, __ret); \ + long __ret = timeout; \ + if (!___wait_cond_timeout(condition)) \ + __ret = __wait_event_interruptible_lock_irq_timeout( \ + wq, condition, lock, timeout); \ __ret; \ }) @@ -875,20 +785,18 @@ do { \ * We plan to remove these interfaces. */ extern void sleep_on(wait_queue_head_t *q); -extern long sleep_on_timeout(wait_queue_head_t *q, - signed long timeout); +extern long sleep_on_timeout(wait_queue_head_t *q, signed long timeout); extern void interruptible_sleep_on(wait_queue_head_t *q); -extern long interruptible_sleep_on_timeout(wait_queue_head_t *q, - signed long timeout); +extern long interruptible_sleep_on_timeout(wait_queue_head_t *q, signed long timeout); /* * Waitqueues which are removed from the waitqueue_head at wakeup time */ void prepare_to_wait(wait_queue_head_t *q, wait_queue_t *wait, int state); void prepare_to_wait_exclusive(wait_queue_head_t *q, wait_queue_t *wait, int state); +long prepare_to_wait_event(wait_queue_head_t *q, wait_queue_t *wait, int state); void finish_wait(wait_queue_head_t *q, wait_queue_t *wait); -void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait, - unsigned int mode, void *key); +void abort_exclusive_wait(wait_queue_head_t *q, wait_queue_t *wait, unsigned int mode, void *key); int autoremove_wake_function(wait_queue_t *wait, unsigned mode, int sync, void *key); int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key); @@ -934,8 +842,8 @@ int wake_bit_function(wait_queue_t *wait, unsigned mode, int sync, void *key); * One uses wait_on_bit() where one is waiting for the bit to clear, * but has no intention of setting it. */ -static inline int wait_on_bit(void *word, int bit, - int (*action)(void *), unsigned mode) +static inline int +wait_on_bit(void *word, int bit, int (*action)(void *), unsigned mode) { if (!test_bit(bit, word)) return 0; @@ -958,8 +866,8 @@ static inline int wait_on_bit(void *word, int bit, * One uses wait_on_bit_lock() where one is waiting for the bit to * clear with the intention of setting it, and when done, clearing it. */ -static inline int wait_on_bit_lock(void *word, int bit, - int (*action)(void *), unsigned mode) +static inline int +wait_on_bit_lock(void *word, int bit, int (*action)(void *), unsigned mode) { if (!test_and_set_bit(bit, word)) return 0; @@ -983,5 +891,5 @@ int wait_on_atomic_t(atomic_t *val, int (*action)(atomic_t *), unsigned mode) return 0; return out_of_line_wait_on_atomic_t(val, action, mode); } - -#endif + +#endif /* _LINUX_WAIT_H */ |