deal with task_work callbacks adding more work

It doesn't matter on normal return to userland path (we'll recheck the
NOTIFY_RESUME flag anyway), but in case of exit_task_work() we'll
need that as soon as we get callbacks capable of triggering more
task_work_add().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This commit is contained in:
Al Viro 2012-06-27 11:33:29 +04:00
parent ed3e694d78
commit a2d4c71d15

View file

@ -60,19 +60,21 @@ void task_work_run(void)
struct task_struct *task = current;
struct callback_head *p, *q;
raw_spin_lock_irq(&task->pi_lock);
p = task->task_works;
task->task_works = NULL;
raw_spin_unlock_irq(&task->pi_lock);
while (1) {
raw_spin_lock_irq(&task->pi_lock);
p = task->task_works;
task->task_works = NULL;
raw_spin_unlock_irq(&task->pi_lock);
if (unlikely(!p))
return;
if (unlikely(!p))
return;
q = p->next; /* head */
p->next = NULL; /* cut it */
while (q) {
p = q->next;
q->func(q);
q = p;
q = p->next; /* head */
p->next = NULL; /* cut it */
while (q) {
p = q->next;
q->func(q);
q = p;
}
}
}