Paolo Valente 9ae759a36b block, bfq: honor already-setup queue merges ... [ Upstream commit 2d52c58b9c9bdae0ca3df6a1eab5745ab3f7d80b ] The function bfq_setup_merge prepares the merging between two bfq_queues, say bfqq and new_bfqq. To this goal, it assigns bfqq->new_bfqq = new_bfqq. Then, each time some I/O for bfqq arrives, the process that generated that I/O is disassociated from bfqq and associated with new_bfqq (merging is actually a redirection). In this respect, bfq_setup_merge increases new_bfqq->ref in advance, adding the number of processes that are expected to be associated with new_bfqq. Unfortunately, the stable-merging mechanism interferes with this setup. After bfqq->new_bfqq has been set by bfq_setup_merge, and before all the expected processes have been associated with bfqq->new_bfqq, bfqq may happen to be stably merged with a different queue than the current bfqq->new_bfqq. In this case, bfqq->new_bfqq gets changed. So, some of the processes that have been already accounted for in the ref counter of the previous new_bfqq will not be associated with that queue. This creates an unbalance, because those references will never be decremented. This commit fixes this issue by reestablishing the previous, natural behaviour: once bfqq->new_bfqq has been set, it will not be changed until all expected redirections have occurred. Signed-off-by: Davide Zini <davidezini2@gmail.com> Signed-off-by: Paolo Valente <paolo.valente@linaro.org> Link: https://lore.kernel.org/r/20210802141352.74353-2-paolo.valente@linaro.org Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>		2021-09-22 12:28:01 +02:00
..
partitions	partitions: msdos: fix one-byte get_unaligned()	2021-07-20 16:05:39 +02:00
badblocks.c	treewide: Use fallthrough pseudo-keyword	2020-08-23 17:36:59 -05:00
bfq-cgroup.c	bfq: fix blkio cgroup leakage v4	2020-08-18 07:48:08 -07:00
bfq-iosched.c	block, bfq: honor already-setup queue merges	2021-09-22 12:28:01 +02:00
bfq-iosched.h	bfq: fix blkio cgroup leakage v4	2020-08-18 07:48:08 -07:00
bfq-wf2q.c	bfq: fix blkio cgroup leakage v4	2020-08-18 07:48:08 -07:00
bio-integrity.c	block: make function __bio_integrity_free() static	2020-07-02 12:38:18 -06:00
bio.c	bio: fix page leak bio_add_hw_page failure	2021-09-15 09:50:47 +02:00
blk-cgroup-rwstat.c	blk-cgroup: Fix the recursive blkg rwstat	2021-03-30 14:31:48 +02:00
blk-cgroup-rwstat.h	blk-cgroup: separate out blkg_rwstat under CONFIG_BLK_CGROUP_RWSTAT	2019-11-07 12:28:13 -07:00
blk-cgroup.c	blk-cgroup: Use cond_resched() when destroy blkgs	2021-02-13 13:55:13 +01:00
blk-core.c	blk-mq: fix kernel panic during iterating over flush request	2021-09-12 08:58:27 +02:00
blk-crypto-fallback.c	block: rename generic_make_request to submit_bio_noacct	2020-07-01 07:27:24 -06:00
blk-crypto-internal.h	block: make blk_crypto_rq_bio_prep() able to fail	2020-10-05 10:47:43 -06:00
blk-crypto.c	blk-crypto: fix check for too-large dun_bytes	2021-09-15 09:50:30 +02:00
blk-exec.c	block: add a blk_account_io_merge_bio helper	2020-05-27 05:21:23 -06:00
blk-flush.c	blk-mq: fix is_flush_rq	2021-09-12 08:58:27 +02:00
blk-integrity.c	block: remove the unused blk_integrity_merge_bio export	2020-10-06 07:29:53 -06:00
blk-ioc.c	block: remove retry loop in ioc_release_fn()	2020-07-16 10:22:15 -06:00
blk-iocost.c	blk-iocost: fix lockdep warning on blkcg->lock	2021-09-03 10:09:22 +02:00
blk-iolatency.c	blk-iolatency: error out if blk_get_queue() failed in iolatency_set_limit()	2021-08-12 13:22:08 +02:00
blk-lib.c	block: add a bdev_is_partition helper	2020-09-25 08:18:57 -06:00
blk-map.c	block: fix bmd->is_null_mapped initialization	2020-09-23 09:18:39 -06:00
blk-merge.c	block: return ELEVATOR_DISCARD_MERGE if possible	2021-09-15 09:50:28 +02:00
blk-mq-cpumap.c	blk-mq: remove the calling of local_memory_node()	2020-10-20 07:08:17 -06:00
blk-mq-debugfs-zoned.c	block: Cleanup license notice	2019-01-17 21:21:40 -07:00
blk-mq-debugfs.c	blk-mq-debugfs: Add decode for BLK_MQ_F_TAG_HCTX_SHARED	2021-01-19 18:27:29 +01:00
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	kyber: fix out of bounds access when preempted	2021-05-19 10:13:13 +02:00
blk-mq-sched.h	block-5.10-2020-10-12	2020-10-13 12:12:44 -07:00
blk-mq-sysfs.c	blk-mq: move cancel of hctx->run_work to the front of blk_exit_queue	2020-10-09 12:46:28 -06:00
blk-mq-tag.c	blk-mq: clear stale request in tags->rq[] before freeing one request pool	2021-07-14 16:55:58 +02:00
blk-mq-tag.h	blk-mq: clear stale request in tags->rq[] before freeing one request pool	2021-07-14 16:55:58 +02:00
blk-mq-virtio.c	blk-mq: Fix typo in comment	2020-03-17 20:55:21 +01:00
blk-mq.c	blk-mq: clearing flush request reference in tags->rqs[]	2021-09-12 08:58:27 +02:00
blk-mq.h	blk-mq: grab rq->refcount before calling ->fn in blk_mq_tagset_busy_iter	2021-07-14 16:55:58 +02:00
blk-pm.c	scsi: block: Fix a race in the runtime power management code	2021-01-06 14:56:50 +01:00
blk-pm.h	scsi: block: Do not accept any requests while suspended	2021-01-12 20:18:17 +01:00
blk-rq-qos.c	rq-qos: fix missed wake-ups in rq_qos_throttle try two	2021-07-19 09:45:00 +02:00
blk-rq-qos.h	block: fix race between adding/removing rq qos and normal IO	2021-07-14 16:56:00 +02:00
blk-settings.c	blk-settings: align max_sectors on "logical_block_size" boundary	2021-03-04 11:38:22 +01:00
blk-stat.c	blk-stat: make q->stats->lock irqsafe	2020-09-01 16:48:46 -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	blk-mq: move cancel of hctx->run_work to the front of blk_exit_queue	2020-10-09 12:46:28 -06:00
blk-throttle.c	blk-throtl: optimize IOPS throttle for large IO scenarios	2021-09-15 09:50:25 +02:00
blk-timeout.c	block: blk-timeout: delete duplicated word	2020-07-31 16:29:47 -06:00
blk-wbt.c	blk-wbt: make sure throttle is enabled properly	2021-07-14 16:56:12 +02:00
blk-wbt.h	blk-wbt: introduce a new disable state to prevent false positive by rwb_enabled()	2021-07-14 16:56:12 +02:00
blk-zoned.c	blk-zoned: allow BLKREPORTZONE without CAP_SYS_ADMIN	2021-09-18 13:40:06 +02:00
blk.h	blk-throtl: optimize IOPS throttle for large IO scenarios	2021-09-15 09:50:25 +02:00
bounce.c	block: make bio_crypt_clone() able to fail	2020-10-05 10:47:43 -06:00
bsg-lib.c	block: drop double zeroing	2020-09-23 09:18:13 -06:00
bsg.c	scsi: bsg: Remove support for SCSI_IOCTL_SEND_COMMAND	2021-09-18 13:40:11 +02:00
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
elevator.c	block: return ELEVATOR_DISCARD_MERGE if possible	2021-09-15 09:50:28 +02:00
genhd.c	block: Suppress uevent for hidden device when removed	2021-03-30 14:31:52 +02:00
ioctl.c	block: return -EBUSY when there are open partitions in blkdev_reread_part	2021-04-28 13:39:59 +02:00
ioprio.c	block: grant IOPRIO_CLASS_RT to CAP_SYS_NICE	2020-09-01 19:38:33 -06:00
Kconfig	blk-wbt: Remove obsolete multiqueue I/O scheduling comment	2020-09-01 16:49:26 -06:00
Kconfig.iosched	treewide: replace '---help---' in Kconfig files with 'help'	2020-06-14 01:57:21 +09:00
keyslot-manager.c	block/keyslot-manager: prevent crash when num_slots=1	2020-11-20 11:52:52 -07:00
kyber-iosched.c	kyber: fix out of bounds access when preempted	2021-05-19 10:13:13 +02:00
Makefile	blk-mq: merge blk-softirq.c into blk-mq.c	2020-06-24 09:15:56 -06:00
mq-deadline.c	block: return ELEVATOR_DISCARD_MERGE if possible	2021-09-15 09:50:28 +02:00
opal_proto.h	block: sed-opal: Change the check condition for regular session validity	2020-03-12 08:00:10 -06:00
scsi_ioctl.c	drivers-5.10-2020-10-12	2020-10-13 13:04:41 -07:00
sed-opal.c	block: sed-opal: Change the check condition for regular session validity	2020-03-12 08:00:10 -06:00
t10-pi.c	block: Allow t10-pi to be modular	2020-01-06 20:59:04 -07:00