WAIT_EVENT_INTERRUPT

Section: Driver Basics (9)
Updated: February 2011
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NAME

wait_event_interruptible_exclusive_locked_irq - sleep until a condition gets true  

SYNOPSIS

wait_event_interruptible_exclusive_locked_irq(wq, condition);
 

ARGUMENTS

wq

the waitqueue to wait on

condition

a C expression for the event to wait for
 

DESCRIPTION

The process is put to sleep (TASK_INTERRUPTIBLE) until the condition evaluates to true or a signal is received. The condition is checked each time the waitqueue wq is woken up.

It must be called with wq.lock being held. This spinlock is unlocked while sleeping but condition testing is done while lock is held and when this macro exits the lock is held.

The lock is locked/unlocked using spin_lock_irq/spin_unlock_irq functions which must match the way they are locked/unlocked outside of this macro.

The process is put on the wait queue with an WQ_FLAG_EXCLUSIVE flag set thus when other process waits process on the list if this process is awaken further processes are not considered.

wake_up_locked 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.  

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