Commit c1a220e7 authored by Zhang Rui's avatar Zhang Rui Committed by Linus Torvalds
Browse files

pm: introduce new interfaces schedule_work_on() and queue_work_on() 

This interface allows adding a job on a specific cpu.

Although a work struct on a cpu will be scheduled to other cpu if the cpu
dies, there is a recursion if a work task tries to offline the cpu it's
running on.  we need to schedule the task to a specific cpu in this case.
http://bugzilla.kernel.org/show_bug.cgi?id=10897



[oleg@tv-sign.ru: cleanups]
Signed-off-by: default avatarZhang Rui <rui.zhang@intel.com>
Tested-by: default avatarRus <harbour@sfinx.od.ua>
Signed-off-by: default avatarRafael J. Wysocki <rjw@sisk.pl>
Acked-by: default avatarPavel Machek <pavel@ucw.cz>
Signed-off-by: default avatarOleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 0d83304c

include/linux/workqueue.h

+3 −0
Original line number Diff line number Diff line
@@ -179,6 +179,8 @@ __create_workqueue_key(const char *name, int singlethread, 
extern void destroy_workqueue(struct workqueue_struct *wq);



extern int queue_work(struct workqueue_struct *wq, struct work_struct *work);

extern int queue_work_on(int cpu, struct workqueue_struct *wq,

			struct work_struct *work);

extern int queue_delayed_work(struct workqueue_struct *wq,

			struct delayed_work *work, unsigned long delay);

extern int queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
@@ -188,6 +190,7 @@ extern void flush_workqueue(struct workqueue_struct *wq); 
extern void flush_scheduled_work(void);



extern int schedule_work(struct work_struct *work);

extern int schedule_work_on(int cpu, struct work_struct *work);

extern int schedule_delayed_work(struct delayed_work *work, unsigned long delay);

extern int schedule_delayed_work_on(int cpu, struct delayed_work *work,

					unsigned long delay);

kernel/workqueue.c

+38 −1
Original line number Diff line number Diff line
@@ -140,7 +140,6 @@ static void insert_work(struct cpu_workqueue_struct *cwq, 
	wake_up(&cwq->more_work);

}



/* Preempt must be disabled. */

static void __queue_work(struct cpu_workqueue_struct *cwq,

			 struct work_struct *work)

{
@@ -175,6 +174,31 @@ int queue_work(struct workqueue_struct *wq, struct work_struct *work) 
}

EXPORT_SYMBOL_GPL(queue_work);



/**

 * queue_work_on - queue work on specific cpu

 * @cpu: CPU number to execute work on

 * @wq: workqueue to use

 * @work: work to queue

 *

 * Returns 0 if @work was already on a queue, non-zero otherwise.

 *

 * We queue the work to a specific CPU, the caller must ensure it

 * can't go away.

 */

int

queue_work_on(int cpu, struct workqueue_struct *wq, struct work_struct *work)

{

	int ret = 0;



	if (!test_and_set_bit(WORK_STRUCT_PENDING, work_data_bits(work))) {

		BUG_ON(!list_empty(&work->entry));

		__queue_work(wq_per_cpu(wq, cpu), work);

		ret = 1;

	}

	return ret;

}

EXPORT_SYMBOL_GPL(queue_work_on);



static void delayed_work_timer_fn(unsigned long __data)

{

	struct delayed_work *dwork = (struct delayed_work *)__data;
@@ -553,6 +577,19 @@ int schedule_work(struct work_struct *work) 
}

EXPORT_SYMBOL(schedule_work);



/*

 * schedule_work_on - put work task on a specific cpu

 * @cpu: cpu to put the work task on

 * @work: job to be done

 *

 * This puts a job on a specific cpu

 */

int schedule_work_on(int cpu, struct work_struct *work)

{

	return queue_work_on(cpu, keventd_wq, work);

}

EXPORT_SYMBOL(schedule_work_on);



/**

 * schedule_delayed_work - put work task in global workqueue after delay

 * @dwork: job to be done

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