Commit 36576000 authored Oct 26, 2012 by Joonsoo Kim Committed by Tejun Heo Dec 01, 2012

workqueue: add WARN_ON_ONCE() on CPU number to wq_worker_waking_up()



Recently, workqueue code has gone through some changes and we found
some bugs related to concurrency management operations happening on
the wrong CPU.  When a worker is concurrency managed
(!WORKER_NOT_RUNNIG), it should be bound to its associated cpu and
woken up to that cpu.  Add WARN_ON_ONCE() to verify this.

Signed-off-by: Joonsoo Kim <js1304@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

parent 999767be

kernel/workqueue.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -739,9 +739,11 @@ void wq_worker_waking_up(struct task_struct *task, unsigned int cpu)
		{
		struct worker *worker = kthread_data(task);

		if (!(worker->flags & WORKER_NOT_RUNNING))
		if (!(worker->flags & WORKER_NOT_RUNNING)) {
		WARN_ON_ONCE(worker->pool->gcwq->cpu != cpu);
		atomic_inc(get_pool_nr_running(worker->pool));
		}
		}

		/**
		* wq_worker_sleeping - a worker is going to sleep