Commit fa5312d9 authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
  workqueue: change cancel_work_sync() to clear work->data
  workqueue: warn about flush_scheduled_work()
parents 9c688c11 4d707b9f

kernel/workqueue.c

+35 −1
Original line number Diff line number Diff line
@@ -229,6 +229,16 @@ static inline void set_wq_data(struct work_struct *work, 
	atomic_long_set(&work->data, new);

}



/*

 * Clear WORK_STRUCT_PENDING and the workqueue on which it was queued.

 */

static inline void clear_wq_data(struct work_struct *work)

{

	unsigned long flags = *work_data_bits(work) &

				(1UL << WORK_STRUCT_STATIC);

	atomic_long_set(&work->data, flags);

}



static inline

struct cpu_workqueue_struct *get_wq_data(struct work_struct *work)

{
@@ -671,7 +681,7 @@ static int __cancel_work_timer(struct work_struct *work, 
		wait_on_work(work);

	} while (unlikely(ret < 0));



	work_clear_pending(work);

	clear_wq_data(work);

	return ret;

}
@@ -845,6 +855,30 @@ int schedule_on_each_cpu(work_func_t func) 
	return 0;

}



/**

 * flush_scheduled_work - ensure that any scheduled work has run to completion.

 *

 * Forces execution of the kernel-global workqueue and blocks until its

 * completion.

 *

 * Think twice before calling this function!  It's very easy to get into

 * trouble if you don't take great care.  Either of the following situations

 * will lead to deadlock:

 *

 *	One of the work items currently on the workqueue needs to acquire

 *	a lock held by your code or its caller.

 *

 *	Your code is running in the context of a work routine.

 *

 * They will be detected by lockdep when they occur, but the first might not

 * occur very often.  It depends on what work items are on the workqueue and

 * what locks they need, which you have no control over.

 *

 * In most situations flushing the entire workqueue is overkill; you merely

 * need to know that a particular work item isn't queued and isn't running.

 * In such cases you should use cancel_delayed_work_sync() or

 * cancel_work_sync() instead.

 */

void flush_scheduled_work(void)

{

	flush_workqueue(keventd_wq);