From 1411d5a7fbe7dce1568b6f0a94c7cbc69eed1bfe Mon Sep 17 00:00:00 2001 From: Matthew Wilcox Date: Thu, 6 Dec 2007 12:00:00 -0500 Subject: [PATCH] Add wait_event_killable Signed-off-by: Matthew Wilcox --- include/linux/wait.h | 41 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+) diff --git a/include/linux/wait.h b/include/linux/wait.h index 0a410a449258..1f4fb0a81ecd 100644 --- a/include/linux/wait.h +++ b/include/linux/wait.h @@ -346,6 +346,47 @@ do { \ __ret; \ }) +#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) + +/** + * wait_event_killable - sleep until a condition gets true + * @wq: the waitqueue to wait on + * @condition: a C expression for the event to wait for + * + * The process is put to sleep (TASK_KILLABLE) until the + * @condition evaluates to true or a signal is received. + * The @condition is checked each time the waitqueue @wq is woken up. + * + * wake_up() has to be called after changing any variable that could + * change the result of the wait condition. + * + * The function will return -ERESTARTSYS if it was interrupted by a + * signal and 0 if @condition evaluated to true. + */ +#define wait_event_killable(wq, condition) \ +({ \ + int __ret = 0; \ + if (!(condition)) \ + __wait_event_killable(wq, condition, __ret); \ + __ret; \ +}) + /* * Must be called with the spinlock in the wait_queue_head_t held. */ -- 2.34.1