linux/block
Tejun Heo 8c936f9ea1 iocost: don't reset the inuse weight of under-weighted debtors
When an iocg is in debt, its inuse weight is owned by debt handling and
should stay at 1. This invariant was broken when determining the amount of
surpluses at the beginning of donation calculation - when an iocg's
hierarchical weight is too low, the iocg is excluded from donation
calculation and its inuse is reset to its active regardless of its
indebtedness, triggering warnings like the following:

 WARNING: CPU: 5 PID: 0 at block/blk-iocost.c:1416 iocg_kick_waitq+0x392/0x3a0
 ...
 RIP: 0010:iocg_kick_waitq+0x392/0x3a0
 Code: 00 00 be ff ff ff ff 48 89 4d a8 e8 98 b2 70 00 48 8b 4d a8 85 c0 0f 85 4a fe ff ff 0f 0b e9 43 fe ff ff 0f 0b e9 4d fe ff ff <0f> 0b e9 50 fe ff ff e8 a2 ae 70 00 66 90 0f 1f 44 00 00 55 48 89
 RSP: 0018:ffffc90000200d08 EFLAGS: 00010016
 ...
  <IRQ>
  ioc_timer_fn+0x2e0/0x1470
  call_timer_fn+0xa1/0x2c0
 ...

As this happens only when an iocg's hierarchical weight is negligible, its
impact likely is limited to triggering the warnings. Fix it by skipping
resetting inuse of under-weighted debtors.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Rik van Riel <riel@surriel.com>
Fixes: c421a3eb2e ("blk-iocost: revamp debt handling")
Cc: stable@vger.kernel.org # v5.10+
Link: https://lore.kernel.org/r/YmjODd4aif9BzFuO@slm.duckdns.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-04-27 08:41:11 -06:00
..
partitions block: remove genhd.h 2022-02-02 07:49:59 -07:00
badblocks.c treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
bdev.c Merge branch 'akpm' (patches from Andrew) 2022-03-22 16:11:53 -07:00
bfq-cgroup.c block, bfq: don't move oom_bfqq 2022-02-18 06:13:00 -07:00
bfq-iosched.c Merge branch 'akpm' (patches from Andrew) 2022-03-22 16:11:53 -07:00
bfq-iosched.h block, bfq: cleanup bfq_bfqq_to_bfqg() 2022-02-18 06:13:00 -07:00
bfq-wf2q.c block, bfq: cleanup bfq_bfqq_to_bfqg() 2022-02-18 06:13:00 -07:00
bio-integrity.c for-5.18/block-2022-03-18 2022-03-21 16:48:55 -07:00
bio.c block: fix offset/size check in bio_trim() 2022-04-14 10:15:24 -06:00
blk-cgroup-rwstat.c blk-cgroup: Fix the recursive blkg rwstat 2021-03-05 11:32:15 -07:00
blk-cgroup-rwstat.h block: partition include/linux/blk-cgroup.h 2022-02-11 10:02:41 -07:00
blk-cgroup.c for-5.18/block-2022-04-01 2022-04-01 16:20:00 -07:00
blk-cgroup.h block: don't merge across cgroup boundaries if blkcg is enabled 2022-03-14 19:14:37 -06:00
blk-core.c SCSI misc on 20220324 2022-03-24 19:37:53 -07:00
blk-crypto-fallback.c block: remove the per-bio/request write hint 2022-03-07 12:45:57 -07:00
blk-crypto-internal.h blk-crypto: show crypto capabilities in sysfs 2022-02-28 06:40:23 -07:00
blk-crypto-profile.c blk-crypto: remove blk_crypto_unregister() 2021-11-29 06:38:51 -07:00
blk-crypto-sysfs.c blk-crypto: show crypto capabilities in sysfs 2022-02-28 06:40:23 -07:00
blk-crypto.c blk-crypto: show crypto capabilities in sysfs 2022-02-28 06:40:23 -07:00
blk-flush.c block: pass a block_device and opf to bio_init 2022-02-02 07:49:59 -07:00
blk-ia-ranges.c block: fix memory leak in disk_register_independent_access_ranges 2022-01-23 09:13:09 -07:00
blk-integrity.c blk-crypto: remove blk_crypto_unregister() 2021-11-29 06:38:51 -07:00
blk-ioc.c block: restore the old set_task_ioprio() behaviour wrt PF_EXITING 2022-03-28 06:34:11 -06:00
blk-iocost.c iocost: don't reset the inuse weight of under-weighted debtors 2022-04-27 08:41:11 -06:00
blk-iolatency.c block: fix rq-qos breakage from skipping rq_qos_done_bio() 2022-03-14 14:23:13 -06:00
blk-ioprio.c block: partition include/linux/blk-cgroup.h 2022-02-11 10:02:41 -07:00
blk-ioprio.h block: Introduce the ioprio rq-qos policy 2021-06-21 15:03:40 -06:00
blk-lib.c SCSI misc on 20220324 2022-03-24 19:37:53 -07:00
blk-map.c block-map: add __GFP_ZERO flag for alloc_page in function bio_copy_kern 2022-02-17 07:54:03 -07:00
blk-merge.c for-5.18/write-streams-2022-03-18 2022-03-26 11:51:46 -07:00
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
blk-mq-debugfs.c for-5.18/write-streams-2022-03-18 2022-03-26 11:51:46 -07:00
blk-mq-debugfs.h blk-mq: manage hctx map via xarray 2022-03-08 19:39:38 -07:00
blk-mq-pci.c
blk-mq-rdma.c
blk-mq-sched.c block: limit request dispatch loop duration 2022-03-17 20:31:43 -06:00
blk-mq-sched.h block: move blk_mq_sched_assign_ioc to blk-ioc.c 2021-11-29 06:41:29 -07:00
blk-mq-sysfs.c blk-mq: prepare for implementing hctx table via xarray 2022-03-08 17:57:19 -07:00
blk-mq-tag.c blk-mq: manage hctx map via xarray 2022-03-08 19:39:38 -07:00
blk-mq-tag.h blk-mq: Delete busy_iter_fn 2021-12-06 13:18:47 -07:00
blk-mq-virtio.c blk-mq: Fix typo in comment 2020-03-17 20:55:21 +01:00
blk-mq.c block: don't print I/O error warning for dead disks 2022-04-15 06:33:03 -06:00
blk-mq.h blk-mq: manage hctx map via xarray 2022-03-08 19:39:38 -07:00
blk-pm.c scsi: block: pm: Always set request queue runtime active in blk_post_runtime_resume() 2021-12-22 23:38:29 -05:00
blk-pm.h block: Remove unused blk_pm_*() function definitions 2021-02-22 06:33:48 -07:00
blk-rq-qos.c rq-qos: fix missed wake-ups in rq_qos_throttle try two 2021-06-08 15:12:57 -06:00
blk-rq-qos.h block: fix rq-qos breakage from skipping rq_qos_done_bio() 2022-03-14 14:23:13 -06:00
blk-settings.c scsi: block: Remove REQ_OP_WRITE_SAME support 2022-02-22 21:11:08 -05:00
blk-stat.c block: make queue stat accounting a reference 2021-12-14 17:23:05 -07:00
blk-stat.h block: make queue stat accounting a reference 2021-12-14 17:23:05 -07:00
blk-sysfs.c SCSI misc on 20220324 2022-03-24 19:37:53 -07:00
blk-throttle.c block: cancel all throttled bios in del_gendisk() 2022-03-18 09:57:56 -06:00
blk-throttle.h block: cancel all throttled bios in del_gendisk() 2022-03-18 09:57:56 -06:00
blk-timeout.c block: blk-timeout: delete duplicated word 2020-07-31 16:29:47 -06:00
blk-wbt.c blk-wbt: prevent NULL pointer dereference in wb_timer_fn 2021-10-19 06:13:41 -06:00
blk-wbt.h blk-wbt: remove wbt_track stub 2022-03-31 12:58:38 -06:00
blk-zoned.c SCSI misc on 20220324 2022-03-24 19:37:53 -07:00
blk.h SCSI misc on 20220324 2022-03-24 19:37:53 -07:00
bounce.c for-5.18/write-streams-2022-03-18 2022-03-26 11:51:46 -07:00
bsg-lib.c block: remove the gendisk argument to blk_execute_rq 2021-11-29 06:41:29 -07:00
bsg.c scsi: bsg: Fix device unregistration 2021-09-14 00:22:15 -04:00
disk-events.c block: remove genhd.h 2022-02-02 07:49:59 -07:00
elevator.c for-5.18/block-2022-03-18 2022-03-21 16:48:55 -07:00
elevator.h block: move elevator.h to block/ 2021-10-18 06:17:01 -06:00
fops.c for-5.18/write-streams-2022-03-18 2022-03-26 11:51:46 -07:00
genhd.c for-5.18/block-2022-04-01 2022-04-01 16:20:00 -07:00
holder.c block: remove genhd.h 2022-02-02 07:49:59 -07:00
ioctl.c block/compat_ioctl: fix range check in BLKGETSIZE 2022-04-15 06:32:40 -06:00
ioprio.c for-5.17/block-2022-01-11 2022-01-12 10:26:52 -08:00
Kconfig block: add pi for extended integrity 2022-03-07 12:48:35 -07:00
Kconfig.iosched block: only build the icq tracking code when needed 2021-12-16 10:59:02 -07:00
kyber-iosched.c block: make queue stat accounting a reference 2021-12-14 17:23:05 -07:00
Makefile blk-crypto: show crypto capabilities in sysfs 2022-02-28 06:40:23 -07:00
mq-deadline.c block: fix async_depth sysfs interface for mq-deadline 2022-01-20 10:54:02 -07:00
opal_proto.h block: sed-opal: Change the check condition for regular session validity 2020-03-12 08:00:10 -06:00
sed-opal.c block: remove genhd.h 2022-02-02 07:49:59 -07:00
t10-pi.c block: add pi for extended integrity 2022-03-07 12:48:35 -07:00