Commit d302f017 authored by Tejun Heo's avatar Tejun Heo
Browse files

workqueue: implement worker_{set|clr}_flags() 



Implement worker_{set|clr}_flags() to manipulate worker flags.  These
are currently simple wrappers but logics to track the current worker
state and the current level of concurrency will be added.

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 7e11629d

kernel/workqueue.c

+40 −8
Original line number Diff line number Diff line
@@ -411,6 +411,38 @@ static void wake_up_worker(struct global_cwq *gcwq) 
		wake_up_process(worker->task);

}



/**

 * worker_set_flags - set worker flags

 * @worker: worker to set flags for

 * @flags: flags to set

 * @wakeup: wakeup an idle worker if necessary

 *

 * Set @flags in @worker->flags.

 *

 * LOCKING:

 * spin_lock_irq(gcwq->lock).

 */

static inline void worker_set_flags(struct worker *worker, unsigned int flags,

				    bool wakeup)

{

	worker->flags |= flags;

}



/**

 * worker_clr_flags - clear worker flags

 * @worker: worker to set flags for

 * @flags: flags to clear

 *

 * Clear @flags in @worker->flags.

 *

 * LOCKING:

 * spin_lock_irq(gcwq->lock).

 */

static inline void worker_clr_flags(struct worker *worker, unsigned int flags)

{

	worker->flags &= ~flags;

}



/**

 * busy_worker_head - return the busy hash head for a work

 * @gcwq: gcwq of interest
@@ -776,7 +808,7 @@ static void worker_enter_idle(struct worker *worker) 
	BUG_ON(!list_empty(&worker->entry) &&

	       (worker->hentry.next || worker->hentry.pprev));



	worker->flags |= WORKER_IDLE;

	worker_set_flags(worker, WORKER_IDLE, false);

	gcwq->nr_idle++;



	/* idle_list is LIFO */
@@ -800,7 +832,7 @@ static void worker_leave_idle(struct worker *worker) 
	struct global_cwq *gcwq = worker->gcwq;



	BUG_ON(!(worker->flags & WORKER_IDLE));

	worker->flags &= ~WORKER_IDLE;

	worker_clr_flags(worker, WORKER_IDLE);

	gcwq->nr_idle--;

	list_del_init(&worker->entry);

}
@@ -890,7 +922,7 @@ static struct worker *create_worker(struct global_cwq *gcwq, bool bind) 
 */

static void start_worker(struct worker *worker)

{

	worker->flags |= WORKER_STARTED;

	worker_set_flags(worker, WORKER_STARTED, false);

	worker->gcwq->nr_workers++;

	worker_enter_idle(worker);

	wake_up_process(worker->task);
@@ -920,7 +952,7 @@ static void destroy_worker(struct worker *worker) 
		gcwq->nr_idle--;



	list_del_init(&worker->entry);

	worker->flags |= WORKER_DIE;

	worker_set_flags(worker, WORKER_DIE, false);



	spin_unlock_irq(&gcwq->lock);
@@ -2214,10 +2246,10 @@ static int __cpuinit trustee_thread(void *__gcwq) 
	BUG_ON(gcwq->cpu != smp_processor_id());



	list_for_each_entry(worker, &gcwq->idle_list, entry)

		worker->flags |= WORKER_ROGUE;

		worker_set_flags(worker, WORKER_ROGUE, false);



	for_each_busy_worker(worker, i, pos, gcwq)

		worker->flags |= WORKER_ROGUE;

		worker_set_flags(worker, WORKER_ROGUE, false);



	/*

	 * We're now in charge.  Notify and proceed to drain.  We need
@@ -2324,10 +2356,10 @@ static int __devinit workqueue_cpu_callback(struct notifier_block *nfb, 


		/* clear ROGUE from all workers */

		list_for_each_entry(worker, &gcwq->idle_list, entry)

			worker->flags &= ~WORKER_ROGUE;

			worker_clr_flags(worker, WORKER_ROGUE);



		for_each_busy_worker(worker, i, pos, gcwq)

			worker->flags &= ~WORKER_ROGUE;

			worker_clr_flags(worker, WORKER_ROGUE);

		break;

	}