linux-stable/drivers/md
Shenghui Wang b2d84967f0 bcache: do not mark writeback_running too early
[ Upstream commit 79b791466e ]

A fresh backing device is not attached to any cache_set, and
has no writeback kthread created until first attached to some
cache_set.

But bch_cached_dev_writeback_init run
"
	dc->writeback_running		= true;
	WARN_ON(test_and_clear_bit(BCACHE_DEV_WB_RUNNING,
			&dc->disk.flags));
"
for any newly formatted backing devices.

For a fresh standalone backing device, we can get something like
following even if no writeback kthread created:
------------------------
/sys/block/bcache0/bcache# cat writeback_running
1
/sys/block/bcache0/bcache# cat writeback_rate_debug
rate:		512.0k/sec
dirty:		0.0k
target:		0.0k
proportional:	0.0k
integral:	0.0k
change:		0.0k/sec
next io:	-15427384ms

The none ZERO fields are misleading as no alive writeback kthread yet.

Set dc->writeback_running false as no writeback thread created in
bch_cached_dev_writeback_init().

We have writeback thread created and woken up in bch_cached_dev_writeback
_start(). Set dc->writeback_running true before bch_writeback_queue()
called, as a writeback thread will check if dc->writeback_running is true
before writing back dirty data, and hung if false detected.

After the change, we can get the following output for a fresh standalone
backing device:
-----------------------
/sys/block/bcache0/bcache$ cat writeback_running
0
/sys/block/bcache0/bcache# cat writeback_rate_debug
rate:		0.0k/sec
dirty:		0.0k
target:		0.0k
proportional:	0.0k
integral:	0.0k
change:		0.0k/sec
next io:	0ms

v1 -> v2:
  Set dc->writeback_running before bch_writeback_queue() called,

Signed-off-by: Shenghui Wang <shhuiw@foxmail.com>
Signed-off-by: Coly Li <colyli@suse.de>

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-12-05 09:20:07 +01:00
..
bcache bcache: do not mark writeback_running too early 2019-12-05 09:20:07 +01:00
persistent-data dm space map metadata: fix missing store of apply_bops() return value 2019-08-29 08:28:56 +02:00
dm-bio-prison-v1.c dm: adjust structure members to improve alignment 2018-06-08 11:53:14 -04:00
dm-bio-prison-v1.h block: switch bios to blk_status_t 2017-06-09 09:27:32 -06:00
dm-bio-prison-v2.c dm: adjust structure members to improve alignment 2018-06-08 11:53:14 -04:00
dm-bio-prison-v2.h
dm-bio-record.h block: replace bi_bdev with a gendisk pointer and partitions index 2017-08-23 12:49:55 -06:00
dm-bufio.c Revert "dm bufio: fix deadlock with loop device" 2019-08-29 08:28:49 +02:00
dm-builtin.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dm-cache-background-tracker.c dm cache background tracker: fix sparse warning 2018-04-30 15:40:40 -04:00
dm-cache-background-tracker.h
dm-cache-block-types.h
dm-cache-metadata.c dm cache metadata: Fix loading discard bitset 2019-05-25 18:23:38 +02:00
dm-cache-metadata.h
dm-cache-policy-internal.h
dm-cache-policy-smq.c treewide: Use array_size() in vzalloc() 2018-06-12 16:19:22 -07:00
dm-cache-policy.c
dm-cache-policy.h
dm-cache-target.c dm cache: fix bugs when a GFP_NOWAIT allocation fails 2019-10-29 09:20:03 +01:00
dm-core.h dm: disable DISCARD if the underlying storage no longer supports it 2019-08-25 10:48:01 +02:00
dm-crypt.c dm crypt: move detailed message into debug level 2019-09-16 08:22:14 +02:00
dm-delay.c dm delay: fix a crash when invalid device is specified 2019-05-25 18:23:39 +02:00
dm-era-target.c dm: allow targets to return output from messages they are sent 2018-04-03 15:04:10 -04:00
dm-exception-store.c
dm-exception-store.h
dm-flakey.c dm: Check for device sector overflow if CONFIG_LBDAF is not set 2019-01-26 09:32:42 +01:00
dm-integrity.c dm integrity: fix a crash due to BUG_ON in __journal_read_write() 2019-08-29 08:28:55 +02:00
dm-io.c dm: Use kzalloc for all structs with embedded biosets/mempools 2018-06-05 08:47:43 -06:00
dm-ioctl.c dm ioctl: harden copy_params()'s copy_from_user() from malicious users 2018-11-13 11:08:49 -08:00
dm-kcopyd.c dm kcopyd: always complete failed jobs 2019-08-29 08:28:55 +02:00
dm-linear.c dm: Check for device sector overflow if CONFIG_LBDAF is not set 2019-01-26 09:32:42 +01:00
dm-log-userspace-base.c dm: convert to bioset_init()/mempool_init() 2018-05-30 15:33:32 -06:00
dm-log-userspace-transfer.c
dm-log-userspace-transfer.h
dm-log-writes.c dm log writes: make sure super sector log updates are written in order 2019-07-03 13:14:45 +02:00
dm-log.c
dm-mpath.c dm mpath: fix missing call of path selector type->end_io 2019-09-16 08:22:12 +02:00
dm-mpath.h
dm-path-selector.c
dm-path-selector.h
dm-queue-length.c dm mpath selector: more evenly distribute ties 2018-01-29 13:44:58 -05:00
dm-raid.c dm raid: avoid bitmap with raid4/5/6 journal device 2019-12-01 09:16:39 +01:00
dm-raid1.c dm: Check for device sector overflow if CONFIG_LBDAF is not set 2019-01-26 09:32:42 +01:00
dm-region-hash.c - Error path bug fix for overflow tests (Dan) 2018-06-12 18:28:00 -07:00
dm-round-robin.c
dm-rq.c blk-mq: add callback of .cleanup_rq 2019-10-05 13:10:03 +02:00
dm-rq.h dm rq: do not update rq partially in each ending bio 2017-08-28 10:23:28 -04:00
dm-service-time.c dm mpath selector: more evenly distribute ties 2018-01-29 13:44:58 -05:00
dm-snap-persistent.c dm bufio: move dm-bufio.h to include/linux/ 2018-04-03 15:04:23 -04:00
dm-snap-transient.c
dm-snap.c dm snapshot: rework COW throttling to fix deadlock 2019-11-06 13:05:11 +01:00
dm-stats.c treewide: kmalloc() -> kmalloc_array() 2018-06-12 16:19:22 -07:00
dm-stats.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dm-stripe.c dax: Introduce a ->copy_to_iter dax operation 2018-05-22 23:18:31 -07:00
dm-switch.c treewide: Use array_size() in vmalloc() 2018-06-12 16:19:22 -07:00
dm-sysfs.c
dm-table.c dm table: fix invalid memory accesses with too high sector number 2019-08-29 08:28:56 +02:00
dm-target.c dm mpath: fix missing call of path selector type->end_io 2019-09-16 08:22:12 +02:00
dm-thin-metadata.c dm thin metadata: check if in fail_io mode when setting needs_check 2019-09-16 08:22:21 +02:00
dm-thin-metadata.h dm thin: fix passdown_double_checking_shared_status() 2019-01-31 08:14:38 +01:00
dm-thin.c dm thin: add sanity checks to thin-pool and external snapshot creation 2019-04-05 22:32:59 +02:00
dm-uevent.c
dm-uevent.h
dm-unstripe.c dm: Check for device sector overflow if CONFIG_LBDAF is not set 2019-01-26 09:32:42 +01:00
dm-verity-fec.c Refactors rslib and callers to provide a per-instance allocation area 2018-06-05 10:48:05 -07:00
dm-verity-fec.h dm: convert to bioset_init()/mempool_init() 2018-05-30 15:33:32 -06:00
dm-verity-target.c dm verity: use message limit for data block corruption message 2019-07-21 09:03:08 +02:00
dm-verity.h dm verity: add 'check_at_most_once' option to only validate hashes once 2018-04-03 15:04:29 -04:00
dm-writecache.c libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
dm-zero.c dm: don't return errnos from ->map 2017-06-09 09:27:32 -06:00
dm-zoned-metadata.c dm zoned: fix potential NULL dereference in dmz_do_reclaim() 2019-08-29 08:28:59 +02:00
dm-zoned-reclaim.c dm zoned: properly handle backing device failure 2019-08-29 08:28:56 +02:00
dm-zoned-target.c dm zoned: fix invalid memory access 2019-10-01 08:26:10 +02:00
dm-zoned.h dm zoned: properly handle backing device failure 2019-08-29 08:28:56 +02:00
dm.c dm: disable DISCARD if the underlying storage no longer supports it 2019-08-25 10:48:01 +02:00
dm.h dm: move dm_table_destroy() to same header as dm_table_create() 2018-01-17 09:16:06 -05:00
Kconfig dm: add writecache target 2018-06-08 11:59:51 -04:00
Makefile dm: add writecache target 2018-06-08 11:59:51 -04:00
md-bitmap.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input 2018-08-18 16:48:07 -07:00
md-bitmap.h md: Avoid namespace collision with bitmap API 2018-08-01 15:49:39 -07:00
md-cluster.c md-cluster: release RESYNC lock after the last resync message 2018-08-31 17:38:10 -07:00
md-cluster.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
md-faulty.c md: convert to bioset_init()/mempool_init() 2018-05-30 15:33:32 -06:00
md-linear.c md: convert to bioset_init()/mempool_init() 2018-05-30 15:33:32 -06:00
md-linear.h Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md 2017-11-14 16:07:26 -08:00
md-multipath.c treewide: kzalloc() -> kcalloc() 2018-06-12 16:19:22 -07:00
md-multipath.h md: convert to bioset_init()/mempool_init() 2018-05-30 15:33:32 -06:00
md.c md: allow metadata updates while suspending an array - fix 2019-11-24 08:19:58 +01:00
md.h md: don't report active array_state until after revalidate_disk() completes. 2019-10-05 13:10:10 +02:00
raid0.c md/raid0: fix warning message for parameter default_layout 2019-10-29 09:19:37 +01:00
raid0.h md/raid0: avoid RAID0 data corruption due to layout confusion. 2019-10-05 13:10:12 +02:00
raid1-10.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
raid1.c md/raid1: fail run raid1 array when active disk less than one 2019-10-05 13:09:54 +02:00
raid1.h md: convert to bioset_init()/mempool_init() 2018-05-30 15:33:32 -06:00
raid5-cache.c md/raid5: fix 'out of memory' during raid cache recovery 2019-02-06 17:30:16 +01:00
raid5-log.h md/raid5-cache: disable reshape completely 2018-08-31 17:38:09 -07:00
raid5-ppl.c md: convert to bioset_init()/mempool_init() 2018-05-30 15:33:32 -06:00
raid5.c md/raid6: Set R5_ReadError when there is read failure on parity disk 2019-10-05 13:10:10 +02:00
raid5.h Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md 2018-06-09 12:01:36 -07:00
raid10.c md/raid10: prevent access of uninitialized resync_pages offset 2019-12-01 09:17:36 +01:00
raid10.h md: convert to bioset_init()/mempool_init() 2018-05-30 15:33:32 -06:00