On 18/08/2020 13:03, John Garry wrote:
Hi guys,
JFYI, While doing some testing on v5.9-rc1, I stumbled across this:
I bisected to here (hopefully without mistake):
commit 37f4a24c2469a10a4c16c641671bd766e276cf9f
Author: Ming Lei <ming.lei@xxxxxxxxxx>
Date:Tue Jun 30 22:03:57 2020 +0800
blk-mq: centralise related handling into blk_mq_get_driver_tag
Move .nr_active update and request assignment into
blk_mq_get_driver_tag(),
all are good to do during getting driver tag.
Meantime blk-flush related code is simplified and flush request needn't
to update the request table manually any more.
Signed-off-by: Ming Lei <ming.lei@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
I'll verify that tomorrow. I see that there is a fix for that patch
included in v5.9-rc1. Bisect log below:
git bisect start
# bad: [9123e3a74ec7b934a4a099e98af6a61c2f80bbf5] Linux 5.9-rc1
git bisect bad 9123e3a74ec7b934a4a099e98af6a61c2f80bbf5
# good: [bcf876870b95592b52519ed4aafcf9d95999bc9c] Linux 5.8
git bisect good bcf876870b95592b52519ed4aafcf9d95999bc9c
# good: [bcf876870b95592b52519ed4aafcf9d95999bc9c] Linux 5.8
git bisect good bcf876870b95592b52519ed4aafcf9d95999bc9c
# bad: [8186749621ed6b8fc42644c399e8c755a2b6f630] Merge tag
'drm-next-2020-08-06' of git://anongit.freedesktop.org/drm/drm
git bisect bad 8186749621ed6b8fc42644c399e8c755a2b6f630
# bad: [2324d50d051ec0f14a548e78554fb02513d6dcef] Merge tag 'docs-5.9'
of git://git.lwn.net/linux
git bisect bad 2324d50d051ec0f14a548e78554fb02513d6dcef
# bad: [92c59e126b21fd212195358a0d296e787e444087] Merge tag
'arm-defconfig-5.9' of
git://git.kernel.org/pub/scm/linux/kernel/git/soc/soc
git bisect bad 92c59e126b21fd212195358a0d296e787e444087
# bad: [cdc8fcb49905c0b67e355e027cb462ee168ffaa3] Merge tag
'for-5.9/io_uring-20200802' of git://git.kernel.dk/linux-block
git bisect bad cdc8fcb49905c0b67e355e027cb462ee168ffaa3
# good: [ab5c60b79ab6cc50b39bbb21b2f9fb55af900b84] Merge branch 'linus'
of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
git bisect good ab5c60b79ab6cc50b39bbb21b2f9fb55af900b84
# bad: [d958e343bdc3de2643ce25225bed082dc222858d] block: blk-timeout:
delete duplicated word
git bisect bad d958e343bdc3de2643ce25225bed082dc222858d
# bad: [53042f3cc411adc79811ba3cfbca5d7a42a7b806] ps3vram: stop using
->queuedata
git bisect bad 53042f3cc411adc79811ba3cfbca5d7a42a7b806
# good: [621c1f42945e76015c3a585e7a9fe6e71665eba0] block: move struct
block_device to blk_types.h
git bisect good 621c1f42945e76015c3a585e7a9fe6e71665eba0
# good: [36a3df5a4574d5ddf59804fcd0c4e9654c514d9a] blk-mq: put driver
tag when this request is completed
git bisect good 36a3df5a4574d5ddf59804fcd0c4e9654c514d9a
# good: [570e9b73b0af2e5381ca5343759779b8c1ed20e3] blk-mq: move
blk_mq_get_driver_tag into blk-mq.c
git bisect good 570e9b73b0af2e5381ca5343759779b8c1ed20e3
# bad: [b5fc1e8bedf8ad2c6381e0df6331ad5686aca425] blk-mq: remove
pointless call of list_entry_rq() in hctx_show_busy_rq()
git bisect bad b5fc1e8bedf8ad2c6381e0df6331ad5686aca425
# bad: [37f4a24c2469a10a4c16c641671bd766e276cf9f] blk-mq: centralise
related handling into blk_mq_get_driver_tag
git bisect bad 37f4a24c2469a10a4c16c641671bd766e276cf9f
# good: [723bf178f158abd1ce6069cb049581b3cb003aab] blk-mq: move
blk_mq_put_driver_tag() into blk-mq.c
git bisect good 723bf178f158abd1ce6069cb049581b3cb003aab
# first bad commit: [37f4a24c2469a10a4c16c641671bd766e276cf9f] blk-mq:
centralise related handling into blk_mq_get_driver_tag
BTW, only need to change scheduler and not change nr_requests to trigger
this.
Thanks,
John
