linux/block
Harshad Shirwadkar b84477d3eb blk-wbt: fix performance regression in wbt scale_up/scale_down
scale_up wakes up waiters after scaling up. But after scaling max, it
should not wake up more waiters as waiters will not have anything to
do. This patch fixes this by making scale_up (and also scale_down)
return when threshold is reached.

This bug causes increased fdatasync latency when fdatasync and dd
conv=sync are performed in parallel on 4.19 compared to 4.14. This
bug was introduced during refactoring of blk-wbt code.

Fixes: a79050434b ("blk-rq-qos: refactor out common elements of blk-wbt")
Cc: stable@vger.kernel.org
Cc: Josef Bacik <jbacik@fb.com>
Signed-off-by: Harshad Shirwadkar <harshadshirwadkar@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2019-10-06 09:26:41 -06:00
..
partitions docs: admin-guide: add a series of orphaned documents 2019-07-15 11:03:02 -03:00
badblocks.c block: switch all files cleared marked as GPLv2 to SPDX tags 2019-04-30 16:11:57 -06:00
bfq-cgroup.c bfq: Add per-device weight 2019-09-06 14:33:52 -06:00
bfq-iosched.c block, bfq: push up injection only after setting service time 2019-09-17 20:03:49 -06:00
bfq-iosched.h bfq: Add per-device weight 2019-09-06 14:33:52 -06:00
bfq-wf2q.c bfq: Fix the missing barrier in __bfq_entity_update_weight_prio 2019-09-06 14:33:48 -06:00
bio-integrity.c block/bio-integrity: fix a memory leak bug 2019-07-11 20:01:21 -06:00
bio.c block: move same page handling from __bio_add_pc_page to the callers 2019-08-22 07:14:39 -06:00
blk-cgroup.c bfq: Fix bfq linkage error 2019-09-14 11:33:43 -06:00
blk-core.c block: centralize PI remapping logic to the block layer 2019-09-17 20:03:49 -06:00
blk-exec.c block: add SPDX tags to block layer files missing licensing information 2019-04-30 16:12:03 -06:00
blk-flush.c block: fix null pointer dereference in blk_mq_rq_timed_out() 2019-09-27 07:01:25 -06:00
blk-integrity.c block: centralize PI remapping logic to the block layer 2019-09-17 20:03:49 -06:00
blk-ioc.c block: remove the queue_lock indirection 2018-11-15 12:17:28 -07:00
blk-iocost.c iocost: bump up default latency targets for hard disks 2019-09-26 01:12:01 -06:00
blk-iolatency.c blkcg: s/RQ_QOS_CGROUP/RQ_QOS_LATENCY/ 2019-08-28 21:17:08 -06:00
blk-lib.c block: fix 32 bit overflow in __blkdev_issue_discard() 2018-11-14 08:17:18 -07:00
blk-map.c block: remove the bi_phys_segments field in struct bio 2019-06-20 10:29:22 -06:00
blk-merge.c block: Improve physical block alignment of split bios 2019-08-04 21:41:29 -06:00
blk-mq-cpumap.c blk-mq: balance mapping between present CPUs and queues 2019-08-04 21:43:12 -06:00
blk-mq-debugfs-zoned.c block: Cleanup license notice 2019-01-17 21:21:40 -07:00
blk-mq-debugfs.c for-5.3/block-20190708 2019-07-09 10:45:06 -07:00
blk-mq-debugfs.h blk-mq: no need to check return value of debugfs_create functions 2019-06-13 03:00:30 -06:00
blk-mq-pci.c block: Fix blk_mq_*_map_queues() kernel-doc headers 2019-05-31 15:12:34 -06:00
blk-mq-rdma.c block: Fix blk_mq_*_map_queues() kernel-doc headers 2019-05-31 15:12:34 -06:00
blk-mq-sched.c blk-mq: move lockdep_assert_held() into elevator_exit 2019-09-26 00:45:05 -06:00
blk-mq-sched.h block: blk-mq: Remove blk_mq_sched_started_request and started_request 2019-07-23 07:25:09 -06:00
blk-mq-sysfs.c block: split .sysfs_lock into two locks 2019-08-27 10:40:20 -06:00
blk-mq-tag.c blk-mq: introduce blk_mq_tagset_wait_completed_request() 2019-08-04 21:41:29 -06:00
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 block: Fix blk_mq_*_map_queues() kernel-doc headers 2019-05-31 15:12:34 -06:00
blk-mq.c blk-mq: apply normal plugging for HDD 2019-09-27 11:40:21 -06:00
blk-mq.h block: Disable write plugging for zoned block devices 2019-07-10 14:18:01 -06:00
blk-pm.c block: bypass blk_set_runtime_active for uninitialized q->dev 2019-09-12 07:11:56 -06:00
blk-pm.h block: remove the queue_lock indirection 2018-11-15 12:17:28 -07:00
blk-rq-qos.c blk-wbt: fix performance regression in wbt scale_up/scale_down 2019-10-06 09:26:41 -06:00
blk-rq-qos.h blk-wbt: fix performance regression in wbt scale_up/scale_down 2019-10-06 09:26:41 -06:00
blk-settings.c dma-mapping updates for 5.4: 2019-09-19 13:27:23 -07:00
blk-softirq.c block: remove a few unused exports 2018-11-15 12:13:25 -07:00
blk-stat.c block: add SPDX tags to block layer files missing licensing information 2019-04-30 16:12:03 -06:00
blk-stat.h block: deactivate blk_stat timer in wbt_disable_default() 2018-12-12 06:47:51 -07:00
blk-sysfs.c rq-qos: get rid of redundant wbt_update_limits() 2019-09-27 01:13:10 -06:00
blk-throttle.c block: make rq sector size accessible for block stats 2019-09-15 16:02:08 -06:00
blk-timeout.c block: add SPDX tags to block layer files missing licensing information 2019-04-30 16:12:03 -06:00
blk-wbt.c blk-wbt: fix performance regression in wbt scale_up/scale_down 2019-10-06 09:26:41 -06:00
blk-wbt.h block/rq_qos: implement rq_qos_ops->queue_depth_changed() 2019-08-28 21:17:07 -06:00
blk-zoned.c blk-zoned: implement REQ_OP_ZONE_RESET_ALL 2019-08-04 21:41:29 -06:00
blk.h block: fix null pointer dereference in blk_mq_rq_timed_out() 2019-09-27 07:01:25 -06:00
bounce.c block: remove the i argument to bio_for_each_segment_all 2019-04-30 09:26:13 -06:00
bsg-lib.c block: drop device references in bsg_queue_rq() 2019-09-23 11:17:24 -06:00
bsg.c block: switch all files cleared marked as GPLv2 to SPDX tags 2019-04-30 16:11:57 -06:00
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: don't release queue's sysfs lock during switching elevator 2019-09-26 00:45:51 -06:00
genhd.c block: Delay default elevator initialization 2019-09-05 19:52:34 -06:00
ioctl.c block: add SPDX tags to block layer files missing licensing information 2019-04-30 16:12:03 -06:00
ioprio.c docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
Kconfig blkcg: implement blk-iocost 2019-08-28 21:17:12 -06:00
Kconfig.iosched docs: block: convert to ReST 2019-07-15 09:20:27 -03:00
kyber-iosched.c blk-mq: remove blk_mq_put_ctx() 2019-07-02 21:03:27 -06:00
Makefile blkcg: implement blk-iocost 2019-08-28 21:17:12 -06:00
mq-deadline.c block: Introduce elevator features 2019-09-05 19:52:33 -06:00
opal_proto.h block: sed-opal: Removed duplicate OPAL_METHOD_LENGTH definition 2019-08-20 09:34:49 -06:00
partition-generic.c block: fix use-after-free on gendisk 2019-04-22 09:48:12 -06:00
scsi_ioctl.c block: switch all files cleared marked as GPLv2 to SPDX tags 2019-04-30 16:11:57 -06:00
sed-opal.c block: sed-opal: fix sparse warning: convert __be64 data 2019-10-03 14:21:32 -06:00
t10-pi.c block: t10-pi: fix -Wswitch warning 2019-09-23 08:05:19 -06:00