centos man page for wait_event_timeout

WAIT_EVENT_TIMEOUT(9)						   Driver Basics					     WAIT_EVENT_TIMEOUT(9)

NAME
       wait_event_timeout - sleep until a condition gets true or a timeout elapses

SYNOPSIS
       wait_event_timeout(wq, condition, timeout);

ARGUMENTS
       wq
	   the waitqueue to wait on

       condition
	   a C expression for the event to wait for

       timeout
	   timeout, in jiffies

DESCRIPTION
       The process is put to sleep (TASK_UNINTERRUPTIBLE) until the condition evaluates to true. 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 returns 0 if the timeout elapsed, or the remaining jiffies (at least 1) if the condition evaluated to true before the timeout
       elapsed.

COPYRIGHT
Kernel Hackers Manual 3.10					     June 2014						     WAIT_EVENT_TIMEOUT(9)