Commit 08243900 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

writeback: merge bdi_writeback_task and bdi_start_fn 



Move all code for the writeback thread into fs/fs-writeback.c instead of
splitting it over two functions in two files.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarJens Axboe <jaxboe@fusionio.com>
parent c1955ce3

fs/fs-writeback.c

+34 −1
Original line number Diff line number Diff line
@@ -775,12 +775,36 @@ long wb_do_writeback(struct bdi_writeback *wb, int force_wait) 
 * Handle writeback of dirty data for the device backed by this bdi. Also

 * wakes up periodically and does kupdated style flushing.

 */

int bdi_writeback_task(struct bdi_writeback *wb)

int bdi_writeback_thread(void *data)

{

	struct bdi_writeback *wb = data;

	struct backing_dev_info *bdi = wb->bdi;

	unsigned long last_active = jiffies;

	unsigned long wait_jiffies = -1UL;

	long pages_written;



	/*

	 * Add us to the active bdi_list

	 */

	spin_lock_bh(&bdi_lock);

	list_add_rcu(&bdi->bdi_list, &bdi_list);

	spin_unlock_bh(&bdi_lock);



	current->flags |= PF_FLUSHER | PF_SWAPWRITE;

	set_freezable();



	/*

	 * Our parent may run at a different priority, just set us to normal

	 */

	set_user_nice(current, 0);



	/*

	 * Clear pending bit and wakeup anybody waiting to tear us down

	 */

	clear_bit(BDI_pending, &bdi->state);

	smp_mb__after_clear_bit();

	wake_up_bit(&bdi->state, BDI_pending);



	while (!kthread_should_stop()) {

		pages_written = wb_do_writeback(wb, 0);
@@ -813,9 +837,18 @@ int bdi_writeback_task(struct bdi_writeback *wb) 
		try_to_freeze();

	}



	wb->task = NULL;



	/*

	 * Flush any work that raced with us exiting. No new work

	 * will be added, since this bdi isn't discoverable anymore.

	 */

	if (!list_empty(&bdi->work_list))

		wb_do_writeback(wb, 1);

	return 0;

}





/*

 * Start writeback of `nr_pages' pages.  If `nr_pages' is zero, write back

 * the whole world.

include/linux/backing-dev.h

+1 −1
Original line number Diff line number Diff line
@@ -102,7 +102,7 @@ void bdi_unregister(struct backing_dev_info *bdi); 
int bdi_setup_and_register(struct backing_dev_info *, char *, unsigned int);

void bdi_start_writeback(struct backing_dev_info *bdi, long nr_pages);

void bdi_start_background_writeback(struct backing_dev_info *bdi);

int bdi_writeback_task(struct bdi_writeback *wb);

int bdi_writeback_thread(void *data);

int bdi_has_dirty_io(struct backing_dev_info *bdi);

void bdi_arm_supers_timer(void);

mm/backing-dev.c

+1 −43
Original line number Diff line number Diff line
@@ -260,48 +260,6 @@ static void bdi_wb_init(struct bdi_writeback *wb, struct backing_dev_info *bdi) 
	INIT_LIST_HEAD(&wb->b_more_io);

}



static int bdi_start_fn(void *ptr)

{

	struct bdi_writeback *wb = ptr;

	struct backing_dev_info *bdi = wb->bdi;

	int ret;



	/*

	 * Add us to the active bdi_list

	 */

	spin_lock_bh(&bdi_lock);

	list_add_rcu(&bdi->bdi_list, &bdi_list);

	spin_unlock_bh(&bdi_lock);



	current->flags |= PF_FLUSHER | PF_SWAPWRITE;

	set_freezable();



	/*

	 * Our parent may run at a different priority, just set us to normal

	 */

	set_user_nice(current, 0);



	/*

	 * Clear pending bit and wakeup anybody waiting to tear us down

	 */

	clear_bit(BDI_pending, &bdi->state);

	smp_mb__after_clear_bit();

	wake_up_bit(&bdi->state, BDI_pending);



	ret = bdi_writeback_task(wb);



	wb->task = NULL;



	/*

	 * Flush any work that raced with us exiting. No new work

	 * will be added, since this bdi isn't discoverable anymore.

	 */

	if (!list_empty(&bdi->work_list))

		wb_do_writeback(wb, 1);



	return ret;

}



int bdi_has_dirty_io(struct backing_dev_info *bdi)

{

	return wb_has_dirty_io(&bdi->wb);
@@ -425,7 +383,7 @@ static int bdi_forker_task(void *ptr) 
		spin_unlock_bh(&bdi_lock);



		wb = &bdi->wb;

		wb->task = kthread_run(bdi_start_fn, wb, "flush-%s",

		wb->task = kthread_run(bdi_writeback_thread, wb, "flush-%s",

					dev_name(bdi->dev));

		/*

		 * If task creation fails, then readd the bdi to