diff options
Diffstat (limited to 'include/linux/wait.h')
| -rw-r--r-- | include/linux/wait.h | 124 |
1 files changed, 120 insertions, 4 deletions
diff --git a/include/linux/wait.h b/include/linux/wait.h index 158715445ffb..d9f131ecf708 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -206,14 +206,16 @@ void __wake_up_sync(struct wait_queue_head *wq_head, unsigned int mode, int nr); /* * Wakeup macros to be used to report events to the targets. */ +#define poll_to_key(m) ((void *)(__force uintptr_t)(__poll_t)(m)) +#define key_to_poll(m) ((__force __poll_t)(uintptr_t)(void *)(m)) #define wake_up_poll(x, m) \ - __wake_up(x, TASK_NORMAL, 1, (void *) (m)) + __wake_up(x, TASK_NORMAL, 1, poll_to_key(m)) #define wake_up_locked_poll(x, m) \ - __wake_up_locked_key((x), TASK_NORMAL, (void *) (m)) + __wake_up_locked_key((x), TASK_NORMAL, poll_to_key(m)) #define wake_up_interruptible_poll(x, m) \ - __wake_up(x, TASK_INTERRUPTIBLE, 1, (void *) (m)) + __wake_up(x, TASK_INTERRUPTIBLE, 1, poll_to_key(m)) #define wake_up_interruptible_sync_poll(x, m) \ - __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, (void *) (m)) + __wake_up_sync_key((x), TASK_INTERRUPTIBLE, 1, poll_to_key(m)) #define ___wait_cond_timeout(condition) \ ({ \ @@ -597,6 +599,120 @@ do { \ __ret; \ }) +/** + * wait_event_idle - wait for a condition without contributing to system load + * @wq_head: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * + * The process is put to sleep (TASK_IDLE) until the + * @condition evaluates to true. + * The @condition is checked each time the waitqueue @wq_head is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + * + */ +#define wait_event_idle(wq_head, condition) \ +do { \ + might_sleep(); \ + if (!(condition)) \ + ___wait_event(wq_head, condition, TASK_IDLE, 0, 0, schedule()); \ +} while (0) + +/** + * wait_event_idle_exclusive - wait for a condition with contributing to system load + * @wq_head: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * + * The process is put to sleep (TASK_IDLE) until the + * @condition evaluates to true. + * The @condition is checked each time the waitqueue @wq_head is woken up. + * + * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag + * set thus if other processes wait on the same list, when this + * process is woken further processes are not considered. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + * + */ +#define wait_event_idle_exclusive(wq_head, condition) \ +do { \ + might_sleep(); \ + if (!(condition)) \ + ___wait_event(wq_head, condition, TASK_IDLE, 1, 0, schedule()); \ +} while (0) + +#define __wait_event_idle_timeout(wq_head, condition, timeout) \ + ___wait_event(wq_head, ___wait_cond_timeout(condition), \ + TASK_IDLE, 0, timeout, \ + __ret = schedule_timeout(__ret)) + +/** + * wait_event_idle_timeout - sleep without load until a condition becomes true or a timeout elapses + * @wq_head: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * @timeout: timeout, in jiffies + * + * The process is put to sleep (TASK_IDLE) until the + * @condition evaluates to true. The @condition is checked each time + * the waitqueue @wq_head is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + * + * Returns: + * 0 if the @condition evaluated to %false after the @timeout elapsed, + * 1 if the @condition evaluated to %true after the @timeout elapsed, + * or the remaining jiffies (at least 1) if the @condition evaluated + * to %true before the @timeout elapsed. + */ +#define wait_event_idle_timeout(wq_head, condition, timeout) \ +({ \ + long __ret = timeout; \ + might_sleep(); \ + if (!___wait_cond_timeout(condition)) \ + __ret = __wait_event_idle_timeout(wq_head, condition, timeout); \ + __ret; \ +}) + +#define __wait_event_idle_exclusive_timeout(wq_head, condition, timeout) \ + ___wait_event(wq_head, ___wait_cond_timeout(condition), \ + TASK_IDLE, 1, timeout, \ + __ret = schedule_timeout(__ret)) + +/** + * wait_event_idle_exclusive_timeout - sleep without load until a condition becomes true or a timeout elapses + * @wq_head: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * @timeout: timeout, in jiffies + * + * The process is put to sleep (TASK_IDLE) until the + * @condition evaluates to true. The @condition is checked each time + * the waitqueue @wq_head is woken up. + * + * The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag + * set thus if other processes wait on the same list, when this + * process is woken further processes are not considered. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + * + * Returns: + * 0 if the @condition evaluated to %false after the @timeout elapsed, + * 1 if the @condition evaluated to %true after the @timeout elapsed, + * or the remaining jiffies (at least 1) if the @condition evaluated + * to %true before the @timeout elapsed. + */ +#define wait_event_idle_exclusive_timeout(wq_head, condition, timeout) \ +({ \ + long __ret = timeout; \ + might_sleep(); \ + if (!___wait_cond_timeout(condition)) \ + __ret = __wait_event_idle_exclusive_timeout(wq_head, condition, timeout);\ + __ret; \ +}) + extern int do_wait_intr(wait_queue_head_t *, wait_queue_entry_t *); extern int do_wait_intr_irq(wait_queue_head_t *, wait_queue_entry_t *); |