linux/block
Damien Le Moal 7211aef86f block: mq-deadline: Fix write completion handling
For a zoned block device using mq-deadline, if a write request for a
zone is received while another write was already dispatched for the same
zone, dd_dispatch_request() will return NULL and the newly inserted
write request is kept in the scheduler queue waiting for the ongoing
zone write to complete. With this behavior, when no other request has
been dispatched, rq_list in blk_mq_sched_dispatch_requests() is empty
and blk_mq_sched_mark_restart_hctx() not called. This in turn leads to
__blk_mq_free_request() call of blk_mq_sched_restart() to not run the
queue when the already dispatched write request completes. The newly
dispatched request stays stuck in the scheduler queue until eventually
another request is submitted.

This problem does not affect SCSI disk as the SCSI stack handles queue
restart on request completion. However, this problem is can be triggered
the nullblk driver with zoned mode enabled.

Fix this by always requesting a queue restart in dd_dispatch_request()
if no request was dispatched while WRITE requests are queued.

Fixes: 5700f69178 ("mq-deadline: Introduce zone locking support")
Cc: <stable@vger.kernel.org>
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>

Add missing export of blk_mq_sched_restart()

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2018-12-17 11:19:39 -07:00
..
partitions partitions/aix: append null character to print data from disk 2018-07-27 09:17:41 -06:00
badblocks.c badblocks: fix wrong return value in badblocks_set if badblocks are disabled 2017-11-03 11:29:50 -07:00
bfq-cgroup.c blkcg: fix ref count issue with bio_blkcg() using task_css 2018-12-07 22:26:36 -07:00
bfq-iosched.c Linux 4.20-rc6 2018-12-09 17:45:40 -07:00
bfq-iosched.h block, bfq: fix decrement of num_active_groups 2018-12-07 07:40:07 -07:00
bfq-wf2q.c block, bfq: fix decrement of num_active_groups 2018-12-07 07:40:07 -07:00
bio-integrity.c block: remove the bio_integrity_advance export 2018-12-16 08:33:57 -07:00
bio.c block: remove the unused bio_set_pages_dirty and bio_check_pages_dirty exports 2018-12-14 06:17:58 -07:00
blk-cgroup.c blkcg: handle dying request_queue when associating a blkg 2018-12-12 17:43:33 -07:00
blk-core.c block: clear REQ_HIPRI if polling is not supported 2018-12-16 09:01:38 -07:00
blk-exec.c block: remove dead elevator code 2018-11-07 13:42:32 -07:00
blk-flush.c block: add queue_is_mq() helper 2018-11-16 08:34:06 -07:00
blk-integrity.c block: merge BIOVEC_SEG_BOUNDARY into biovec_phys_mergeable 2018-09-24 12:33:57 -06:00
blk-ioc.c block: remove the queue_lock indirection 2018-11-15 12:17:28 -07:00
blk-iolatency.c block: convert io-latency to use rq_qos_wait 2018-12-07 22:26:38 -07:00
blk-lib.c block: fix 32 bit overflow in __blkdev_issue_discard() 2018-11-14 08:17:18 -07:00
blk-map.c Merge branch 'for-4.16/block' of git://git.kernel.dk/linux-block 2018-01-29 11:51:49 -08:00
blk-merge.c block: remove the blk_recount_segments export 2018-12-14 06:17:55 -07:00
blk-mq-cpumap.c blk-mq: initial support for multiple queue maps 2018-11-07 13:45:00 -07:00
blk-mq-debugfs-zoned.c block: Make struct request_queue smaller for CONFIG_BLK_DEV_ZONED=n 2018-07-09 09:07:52 -06:00
blk-mq-debugfs.c blk-mq: export hctx->type in debugfs instead of sysfs 2018-12-17 05:44:45 -07:00
blk-mq-debugfs.h blk-mq-debugfs: support rq_qos 2018-12-16 19:53:47 -07:00
blk-mq-pci.c blk-mq: initial support for multiple queue maps 2018-11-07 13:45:00 -07:00
blk-mq-rdma.c blk-mq-rdma: pass in queue map to blk_mq_rdma_map_queues 2018-12-13 09:59:08 +01:00
blk-mq-sched.c block: mq-deadline: Fix write completion handling 2018-12-17 11:19:39 -07:00
blk-mq-sched.h block: mq-deadline: Fix write completion handling 2018-12-17 11:19:39 -07:00
blk-mq-sysfs.c blk-mq: export hctx->type in debugfs instead of sysfs 2018-12-17 05:44:45 -07:00
blk-mq-tag.c sbitmap: optimize wakeup check 2018-11-30 14:48:04 -07:00
blk-mq-tag.h Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block 2017-11-14 15:32:19 -08:00
blk-mq-virtio.c blk-mq: initial support for multiple queue maps 2018-11-07 13:45:00 -07:00
blk-mq.c blk-mq: fix allocation for queue mapping table 2018-12-17 05:37:23 -07:00
blk-mq.h blk-mq: only dispatch to non-defauly queue maps if they have queues 2018-12-17 05:44:45 -07:00
blk-pm.c block: remove the queue_lock indirection 2018-11-15 12:17:28 -07:00
blk-pm.h block: remove the queue_lock indirection 2018-11-15 12:17:28 -07:00
blk-rq-qos.c blk-mq-debugfs: support rq_qos 2018-12-16 19:53:47 -07:00
blk-rq-qos.h blk-mq-debugfs: support rq_qos 2018-12-16 19:53:47 -07:00
blk-settings.c block: use atomic bitops for ->queue_flags 2018-11-15 12:13:19 -07:00
blk-softirq.c block: remove a few unused exports 2018-11-15 12:13:25 -07:00
blk-stat.c block: remove a few unused exports 2018-11-15 12:13:25 -07:00
blk-stat.h block: deactivate blk_stat timer in wbt_disable_default() 2018-12-12 06:47:51 -07:00
blk-sysfs.c block: only allow polling if a poll queue_map exists 2018-12-04 11:38:19 -07:00
blk-throttle.c blkcg: consolidate bio_issue_init() to be a part of core 2018-12-07 22:26:37 -07:00
blk-timeout.c block: don't hold the queue_lock over blk_abort_request 2018-11-15 12:13:18 -07:00
blk-wbt.c blk-wbt: export internal state via debugfs 2018-12-16 19:53:49 -07:00
blk-wbt.h block: remove external dependency on wbt_flags 2018-07-09 09:07:54 -06:00
blk-zoned.c block: add queue_is_mq() helper 2018-11-16 08:34:06 -07:00
blk.h block: sum requests in the plug structure 2018-11-26 10:35:22 -07:00
bounce.c blkcg: remove bio->bi_css and instead use bio->bi_blkg 2018-12-07 22:26:37 -07:00
bsg-lib.c bsg: move bsg-lib parts outside of request queue 2018-11-07 13:42:33 -07:00
bsg.c block: add queue_is_mq() helper 2018-11-16 08:34:06 -07:00
cmdline-parser.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compat_ioctl.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
elevator.c block: add queue_is_mq() helper 2018-11-16 08:34:06 -07:00
genhd.c block: return just one value from part_in_flight 2018-12-10 08:30:38 -07:00
ioctl.c block: Introduce BLKGETNRZONES ioctl 2018-10-25 11:17:40 -06:00
ioprio.c block: add ioprio_check_cap function 2018-05-31 10:50:54 -04:00
Kconfig blk-wbt: kill check for legacy queue type 2018-11-07 13:42:32 -07:00
Kconfig.iosched block: remove legacy IO schedulers 2018-11-07 13:42:32 -07:00
kyber-iosched.c blk-mq: allow software queue to map to multiple hardware queues 2018-11-07 13:44:59 -07:00
Makefile block: remove legacy IO schedulers 2018-11-07 13:42:32 -07:00
mq-deadline.c block: mq-deadline: Fix write completion handling 2018-12-17 11:19:39 -07:00
opal_proto.h block: sed-opal: Set MBRDone on S3 resume path if TPER is MBREnabled 2017-09-11 09:45:52 -06:00
partition-generic.c block: return just one value from part_in_flight 2018-12-10 08:30:38 -07:00
scsi_ioctl.c block: consistently use GFP_NOIO instead of __GFP_NORECLAIM 2018-05-14 08:55:18 -06:00
sed-opal.c block: sed-opal: Fix a couple off by one bugs 2018-06-20 12:04:06 -06:00
t10-pi.c block: move dif_prepare/dif_complete functions to block layer 2018-07-30 08:27:02 -06:00