Commit 57469821 authored by Tejun Heo's avatar Tejun Heo
Browse files

workqueue: unify local CPU queueing handling 



Queueing functions have been using different methods to determine the
local CPU.

* queue_work() superflously uses get/put_cpu() to acquire and hold the
  local CPU across queue_work_on().

* delayed_work_timer_fn() uses smp_processor_id().

* queue_delayed_work() calls queue_delayed_work_on() with -1 @cpu
  which is interpreted as the local CPU.

* flush_delayed_work[_sync]() were using raw_smp_processor_id().

* __queue_work() interprets %WORK_CPU_UNBOUND as local CPU if the
  target workqueue is bound one but nobody uses this.

This patch converts all functions to uniformly use %WORK_CPU_UNBOUND
to indicate local CPU and use the local binding feature of
__queue_work().  unlikely() is dropped from %WORK_CPU_UNBOUND handling
in __queue_work().

Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent d8e794df

kernel/workqueue.c

+7 −12
Original line number Diff line number Diff line
@@ -1003,7 +1003,7 @@ static void __queue_work(unsigned int cpu, struct workqueue_struct *wq, 
	if (!(wq->flags & WQ_UNBOUND)) {

		struct global_cwq *last_gcwq;



		if (unlikely(cpu == WORK_CPU_UNBOUND))

		if (cpu == WORK_CPU_UNBOUND)

			cpu = raw_smp_processor_id();



		/*
@@ -1103,12 +1103,7 @@ EXPORT_SYMBOL_GPL(queue_work_on); 
 */

bool queue_work(struct workqueue_struct *wq, struct work_struct *work)

{

	bool ret;



	ret = queue_work_on(get_cpu(), wq, work);

	put_cpu();



	return ret;

	return queue_work_on(WORK_CPU_UNBOUND, wq, work);

}

EXPORT_SYMBOL_GPL(queue_work);
@@ -1118,7 +1113,7 @@ void delayed_work_timer_fn(unsigned long __data) 
	struct cpu_workqueue_struct *cwq = get_work_cwq(&dwork->work);



	local_irq_disable();

	__queue_work(smp_processor_id(), cwq->wq, &dwork->work);

	__queue_work(WORK_CPU_UNBOUND, cwq->wq, &dwork->work);

	local_irq_enable();

}

EXPORT_SYMBOL_GPL(delayed_work_timer_fn);
@@ -1172,7 +1167,7 @@ bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq, 


		timer->expires = jiffies + delay;



		if (unlikely(cpu >= 0))

		if (unlikely(cpu != WORK_CPU_UNBOUND))

			add_timer_on(timer, cpu);

		else

			add_timer(timer);
@@ -1198,7 +1193,7 @@ bool queue_delayed_work(struct workqueue_struct *wq, 
	if (delay == 0)

		return queue_work(wq, &dwork->work);



	return queue_delayed_work_on(-1, wq, dwork, delay);

	return queue_delayed_work_on(WORK_CPU_UNBOUND, wq, dwork, delay);

}

EXPORT_SYMBOL_GPL(queue_delayed_work);
@@ -2868,7 +2863,7 @@ bool flush_delayed_work(struct delayed_work *dwork) 
{

	local_irq_disable();

	if (del_timer_sync(&dwork->timer))

		__queue_work(raw_smp_processor_id(),

		__queue_work(WORK_CPU_UNBOUND,

			     get_work_cwq(&dwork->work)->wq, &dwork->work);

	local_irq_enable();

	return flush_work(&dwork->work);
@@ -2891,7 +2886,7 @@ bool flush_delayed_work_sync(struct delayed_work *dwork) 
{

	local_irq_disable();

	if (del_timer_sync(&dwork->timer))

		__queue_work(raw_smp_processor_id(),

		__queue_work(WORK_CPU_UNBOUND,

			     get_work_cwq(&dwork->work)->wq, &dwork->work);

	local_irq_enable();

	return flush_work_sync(&dwork->work);

CRA Git | Maintained and supported by SUSTech CRA and CCSE