Commit 7c87df9c authored May 24, 2016 by Jiri Kosina Committed by Jens Axboe May 24, 2016

bcache: bch_writeback_thread() is not freezable



bch_writeback_thread() is calling try_to_freeze(), but that's just an
expensive no-op given the fact that the thread is not marked freezable.

I/O helper kthreads, exactly such as the bcache writeback thread, actually
shouldn't be freezable, because they are potentially necessary for
finalizing the image write-out.

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>

parent ba36c21b

drivers/md/bcache/writeback.c

+0 −3

Original line number	Diff line number	Diff line
		@@ -12,7 +12,6 @@
		#include "writeback.h"

		#include <linux/delay.h>
		#include <linux/freezer.h>
		#include <linux/kthread.h>
		#include <trace/events/bcache.h>

		@@ -228,7 +227,6 @@ static void read_dirty(struct cached_dev *dc)
		*/

		while (!kthread_should_stop()) {
		try_to_freeze();

		w = bch_keybuf_next(&dc->writeback_keys);
		if (!w)
		@@ -433,7 +431,6 @@ static int bch_writeback_thread(void *arg)
		if (kthread_should_stop())
		return 0;

		try_to_freeze();
		schedule();
		continue;
		}