__wake_up_sync(9)
NAME
__wake_up_sync - wake up threads blocked on a waitqueue.
SYNOPSIS
void __wake_up_sync(wait_queue_head_t * q, unsigned int mode,
int nr_exclusive);
ARGUMENTS
- q
- the waitqueue
- mode
- which threads
- nr_exclusive
- how many wake-one or wake-many threads to wake up
DESCRIPTION
The sync wakeup differs that the waker knows that it will schedule away
soon, so while the target thread will be woken up, it will not be
migrated to another CPU - ie. the two threads are ´synchronized´ with
each other. This can prevent needless bouncing between CPUs.
On UP it can prevent extra preemption.