Commit bc35f7ef authored by Lai Jiangshan's avatar Lai Jiangshan Committed by Tejun Heo
Browse files

workqueue: Convert the type of pool->nr_running to int 



It is only modified in associated CPU, so it doesn't need to be atomic.

tj: Comment updated.

Signed-off-by: default avatarLai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent cc5bff38

kernel/workqueue.c

+16 −13
Original line number Diff line number Diff line
@@ -154,8 +154,13 @@ struct worker_pool { 


	unsigned long		watchdog_ts;	/* L: watchdog timestamp */



	/* The current concurrency level. */

	atomic_t		nr_running;

	/*

	 * The counter is incremented in a process context on the associated CPU

	 * w/ preemption disabled, and decremented or reset in the same context

	 * but w/ pool->lock held. The readers grab pool->lock and are

	 * guaranteed to see if the counter reached zero.

	 */

	int			nr_running;



	struct list_head	worklist;	/* L: list of pending works */
@@ -777,7 +782,7 @@ static bool work_is_canceling(struct work_struct *work) 


static bool __need_more_worker(struct worker_pool *pool)

{

	return !atomic_read(&pool->nr_running);

	return !pool->nr_running;

}



/*
@@ -802,8 +807,7 @@ static bool may_start_working(struct worker_pool *pool) 
/* Do I need to keep working?  Called from currently running workers. */

static bool keep_working(struct worker_pool *pool)

{

	return !list_empty(&pool->worklist) &&

		atomic_read(&pool->nr_running) <= 1;

	return !list_empty(&pool->worklist) && (pool->nr_running <= 1);

}



/* Do we need a new worker?  Called from manager. */
@@ -873,7 +877,7 @@ void wq_worker_running(struct task_struct *task) 
	 */

	preempt_disable();

	if (!(worker->flags & WORKER_NOT_RUNNING))

		atomic_inc(&worker->pool->nr_running);

		worker->pool->nr_running++;

	preempt_enable();

	worker->sleeping = 0;

}
@@ -917,8 +921,8 @@ void wq_worker_sleeping(struct task_struct *task) 
		return;

	}



	if (atomic_dec_and_test(&pool->nr_running) &&

	    !list_empty(&pool->worklist))

	pool->nr_running--;

	if (need_more_worker(pool))

		wake_up_worker(pool);

	raw_spin_unlock_irq(&pool->lock);

}
@@ -973,7 +977,7 @@ static inline void worker_set_flags(struct worker *worker, unsigned int flags) 
	/* If transitioning into NOT_RUNNING, adjust nr_running. */

	if ((flags & WORKER_NOT_RUNNING) &&

	    !(worker->flags & WORKER_NOT_RUNNING)) {

		atomic_dec(&pool->nr_running);

		pool->nr_running--;

	}



	worker->flags |= flags;
@@ -1005,7 +1009,7 @@ static inline void worker_clr_flags(struct worker *worker, unsigned int flags) 
	 */

	if ((flags & WORKER_NOT_RUNNING) && (oflags & WORKER_NOT_RUNNING))

		if (!(worker->flags & WORKER_NOT_RUNNING))

			atomic_inc(&pool->nr_running);

			pool->nr_running++;

}



/**
@@ -1806,8 +1810,7 @@ static void worker_enter_idle(struct worker *worker) 
		mod_timer(&pool->idle_timer, jiffies + IDLE_WORKER_TIMEOUT);



	/* Sanity check nr_running. */

	WARN_ON_ONCE(pool->nr_workers == pool->nr_idle &&

		     atomic_read(&pool->nr_running));

	WARN_ON_ONCE(pool->nr_workers == pool->nr_idle && pool->nr_running);

}



/**
@@ -4985,7 +4988,7 @@ static void unbind_workers(int cpu) 
		 * an unbound (in terms of concurrency management) pool which

		 * are served by workers tied to the pool.

		 */

		atomic_set(&pool->nr_running, 0);

		pool->nr_running = 0;



		/*

		 * With concurrency management just turned off, a busy