Commit 7576958a authored Feb 14, 2011 by Tejun Heo

workqueue: wake up a worker when a rescuer is leaving a gcwq



After executing the matching works, a rescuer leaves the gcwq whether
there are more pending works or not.  This may decrease the
concurrency level to zero and stall execution until a new work item is
queued on the gcwq.

Make rescuer wake up a regular worker when it leaves a gcwq if there
are more works to execute, so that execution isn't stalled.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Ray Jui <rjui@broadcom.com>
Cc: stable@kernel.org

parent 795abaf1

kernel/workqueue.c

+9 −0

Original line number	Diff line number	Diff line
		@@ -2047,6 +2047,15 @@ repeat:
		move_linked_works(work, scheduled, &n);

		process_scheduled_works(rescuer);

		/*
		* Leave this gcwq. If keep_working() is %true, notify a
		* regular worker; otherwise, we end up with 0 concurrency
		* and stalling the execution.
		*/
		if (keep_working(gcwq))
		wake_up_worker(gcwq);

		spin_unlock_irq(&gcwq->lock);
		}