The following commit has been merged in the linux branch: commit 8c53e46314562fe814b0afef6cfcbd2f562b017c Author: Linus Torvalds torvalds@linux-foundation.org Date: Wed Oct 14 09:16:42 2009 -0700

workqueue: add 'flush_delayed_work()' to run and wait for delayed work

It basically turns a delayed work into an immediate work, and then waits for it to finish, thus allowing you to force (and wait for) an immediate flush of a delayed work.

We'll want to use this in the tty layer to clean up tty_flush_to_ldisc().

Acked-by: Oleg Nesterov oleg@redhat.com [ Fixed to use 'del_timer_sync()' as noted by Oleg ] Signed-off-by: Linus Torvalds torvalds@linux-foundation.org

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h index 7ef0c7b..cf24c20 100644 --- a/include/linux/workqueue.h +++ b/include/linux/workqueue.h @@ -207,6 +207,7 @@ extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,

extern void flush_workqueue(struct workqueue_struct *wq); extern void flush_scheduled_work(void); +extern void flush_delayed_work(struct delayed_work *work);

extern int schedule_work(struct work_struct *work); extern int schedule_work_on(int cpu, struct work_struct *work); diff --git a/kernel/workqueue.c b/kernel/workqueue.c index addfe2d..47cdd7e 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -640,6 +640,24 @@ int schedule_delayed_work(struct delayed_work *dwork, EXPORT_SYMBOL(schedule_delayed_work);

/** + * flush_delayed_work - block until a dwork_struct's callback has terminated + * @dwork: the delayed work which is to be flushed + * + * Any timeout is cancelled, and any pending work is run immediately. + */ +void flush_delayed_work(struct delayed_work *dwork) +{ + if (del_timer_sync(&dwork->timer)) { + struct cpu_workqueue_struct *cwq; + cwq = wq_per_cpu(keventd_wq, get_cpu()); + __queue_work(cwq, &dwork->work); + put_cpu(); + } + flush_work(&dwork->work); +} +EXPORT_SYMBOL(flush_delayed_work); + +/** * schedule_delayed_work_on - queue work in global workqueue on CPU after delay * @cpu: cpu to use * @dwork: job to be done