Now we avoid throttling swap writes by determining whether the current
process is kswapd (aka current_is_kswapd()), but swap writes can come
from either kswapd or direct reclaim, so the swap writes from direct
reclaim will still be throttled.
When a process holds a lock to allocate a free page, and enters direct
reclaim because there is no free memory, then it might trigger a hung
due to the wbt throttling that causes other processes to fail to get
the lock.
Both kswapd and direct reclaim set the REQ_SWAP flag, so use REQ_SWAP
instead of current_is_kswapd() to avoid throttling swap writes. Also
renamed WBT_KSWAPD to WBT_SWAP and WBT_RWQ_KSWAPD to WBT_RWQ_SWAP.
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20240604030522.3686177-1-libaokun@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Move the cache control settings into the queue_limits so that the flags
can be set atomically with the device queue frozen.
Add new features and flags field for the driver set flags, and internal
(usually sysfs-controlled) flags in the block layer. Note that we'll
eventually remove enough field from queue_limits to bring it back to the
previous size.
The disable flag is inverted compared to the previous meaning, which
means it now survives a rescan, similar to the max_sectors and
max_discard_sectors user limits.
The FLUSH and FUA flags are now inherited by blk_stack_limits, which
simplified the code in dm a lot, but also causes a slight behavior
change in that dm-switch and dm-unstripe now advertise a write cache
despite setting num_flush_bios to 0. The I/O path will handle this
gracefully, but as far as I can tell the lack of num_flush_bios
and thus flush support is a pre-existing data integrity bug in those
targets that really needs fixing, after which a non-zero num_flush_bios
should be required in dm for targets that map to underlying devices.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Link: https://lore.kernel.org/r/20240617060532.127975-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The detection of dirty-throttled tasks in blk-wbt has been subtly broken
since its beginning in 2016. Namely if we are doing cgroup writeback and
the throttled task is not in the root cgroup, balance_dirty_pages() will
set dirty_sleep for the non-root bdi_writeback structure. However
blk-wbt checks dirty_sleep only in the root cgroup bdi_writeback
structure. Thus detection of recently throttled tasks is not working in
this case (we noticed this when we switched to cgroup v2 and suddently
writeback was slow).
Since blk-wbt has no easy way to get to proper bdi_writeback and
furthermore its intention has always been to work on the whole device
rather than on individual cgroups, just move the dirty_sleep timestamp
from bdi_writeback to backing_dev_info. That fixes the checking for
recently throttled task and saves memory for everybody as a bonus.
CC: stable@vger.kernel.org
Fixes: b57d74aff9 ("writeback: track if we're sleeping on progress in balance_dirty_pages()")
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240123175826.21452-1-jack@suse.cz
[axboe: fixup indentation errors]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Convert any user of ktime_get_ns() to use blk_time_get_ns(), and
ktime_get() to blk_time_get(), so we have a unified API for querying the
current time in nanoseconds or as ktime.
No functional changes intended, this patch just wraps ktime_get_ns()
and ktime_get() with a block helper.
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use the queue wide write back cache tracking insted of duplicating the
value in strut rq_wb.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20231226090747.204969-1-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
* for-6.5/block-late:
blk-sysfs: add a new attr_group for blk_mq
blk-iocost: move wbt_enable/disable_default() out of spinlock
blk-wbt: cleanup rwb_enabled() and wbt_disabled()
blk-wbt: remove dead code to handle wbt enable/disable with io inflight
blk-wbt: don't create wbt sysfs entry if CONFIG_BLK_WBT is disabled
blk-mq: fix two misuses on RQF_USE_SCHED
blk-throttle: Fix io statistics for cgroup v1
bcache: Fix bcache device claiming
bcache: Alloc holder object before async registration
raid10: avoid spin_lock from fastpath from raid10_unplug()
md: fix 'delete_mutex' deadlock
md: use mddev->external to select holder in export_rdev()
md/raid1-10: fix casting from randomized structure in raid1_submit_write()
md/raid10: fix the condition to call bio_end_io_acct()
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Merge tag 'for-6.5/block-2023-06-23' of git://git.kernel.dk/linux
Pull block updates from Jens Axboe:
- NVMe pull request via Keith:
- Various cleanups all around (Irvin, Chaitanya, Christophe)
- Better struct packing (Christophe JAILLET)
- Reduce controller error logs for optional commands (Keith)
- Support for >=64KiB block sizes (Daniel Gomez)
- Fabrics fixes and code organization (Max, Chaitanya, Daniel
Wagner)
- bcache updates via Coly:
- Fix a race at init time (Mingzhe Zou)
- Misc fixes and cleanups (Andrea, Thomas, Zheng, Ye)
- use page pinning in the block layer for dio (David)
- convert old block dio code to page pinning (David, Christoph)
- cleanups for pktcdvd (Andy)
- cleanups for rnbd (Guoqing)
- use the unchecked __bio_add_page() for the initial single page
additions (Johannes)
- fix overflows in the Amiga partition handling code (Michael)
- improve mq-deadline zoned device support (Bart)
- keep passthrough requests out of the IO schedulers (Christoph, Ming)
- improve support for flush requests, making them less special to deal
with (Christoph)
- add bdev holder ops and shutdown methods (Christoph)
- fix the name_to_dev_t() situation and use cases (Christoph)
- decouple the block open flags from fmode_t (Christoph)
- ublk updates and cleanups, including adding user copy support (Ming)
- BFQ sanity checking (Bart)
- convert brd from radix to xarray (Pankaj)
- constify various structures (Thomas, Ivan)
- more fine grained persistent reservation ioctl capability checks
(Jingbo)
- misc fixes and cleanups (Arnd, Azeem, Demi, Ed, Hengqi, Hou, Jan,
Jordy, Li, Min, Yu, Zhong, Waiman)
* tag 'for-6.5/block-2023-06-23' of git://git.kernel.dk/linux: (266 commits)
scsi/sg: don't grab scsi host module reference
ext4: Fix warning in blkdev_put()
block: don't return -EINVAL for not found names in devt_from_devname
cdrom: Fix spectre-v1 gadget
block: Improve kernel-doc headers
blk-mq: don't insert passthrough request into sw queue
bsg: make bsg_class a static const structure
ublk: make ublk_chr_class a static const structure
aoe: make aoe_class a static const structure
block/rnbd: make all 'class' structures const
block: fix the exclusive open mask in disk_scan_partitions
block: add overflow checks for Amiga partition support
block: change all __u32 annotations to __be32 in affs_hardblocks.h
block: fix signed int overflow in Amiga partition support
block: add capacity validation in bdev_add_partition()
block: fine-granular CAP_SYS_ADMIN for Persistent Reservation
block: disallow Persistent Reservation on partitions
reiserfs: fix blkdev_put() warning from release_journal_dev()
block: fix wrong mode for blkdev_get_by_dev() from disk_scan_partitions()
block: document the holder argument to blkdev_get_by_path
...
'wb_normal' will set to 0 if 'min_lat_nsec' is 0, and 'min_lat_nsec' can
only be set to 0 through sysfs configuration where 'WBT_STATE_OFF_MANUAL'
is set together, in the meantime, they can only be cleared together
through sysfs afterwards. Hence 'wb_normal != 0' is the same as
'rwb->enable_state != WBT_STATE_OFF_MANUAL'.
The code is redundan, hence replace the checking of 'wb_normal' to
'enable_state' in rwb_enabled() and reuse rwb_enabled() for
wbt_disabled().
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230527010644.647900-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
enable or disable wbt is always called with queue freezed, so that wbt
can never be enabled or disabled while io is still inflight, and this
behaviour should always hold to avoid io hang(There have been reported
several times).
Therefor, the code to handle wbt enable/diskble with io inflight is not
and never will be used, hence remove such dead code.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20230527010644.647900-3-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
commit 50e34d7881 ("block: disable the elevator int del_gendisk")
move rq_qos_exit() from disk_release() to del_gendisk(), this will
introduce some problems:
1) If rq_qos_add() is triggered by enabling iocost/iolatency through
cgroupfs, then it can concurrent with del_gendisk(), it's not safe to
write 'q->rq_qos' concurrently.
2) Activate cgroup policy that is relied on rq_qos will call
rq_qos_add() and blkcg_activate_policy(), and if rq_qos_exit() is
called in the middle, null-ptr-dereference will be triggered in
blkcg_activate_policy().
3) blkg_conf_open_bdev() can call blkdev_get_no_open() first to find the
disk, then if rq_qos_exit() from del_gendisk() is done before
rq_qos_add(), then memory will be leaked.
This patch add a new disk level mutex 'rq_qos_mutex':
1) The lock will protect rq_qos_exit() directly.
2) For wbt that doesn't relied on blk-cgroup, rq_qos_add() can only be
called from disk initialization for now because wbt can't be
destructed until rq_qos_exit(), so it's safe not to protect wbt for
now. Hoever, in case that rq_qos dynamically destruction is supported
in the furture, this patch also protect rq_qos_add() from wbt_init()
directly, this is enough because blk-sysfs already synchronize
writers with disk removal.
3) For iocost and iolatency, in order to synchronize disk removal and
cgroup configuration, the lock is held after blkdev_get_no_open()
from blkg_conf_open_bdev(), and is released in blkg_conf_exit().
In order to fix the above memory leak, disk_live() is checked after
holding the new lock.
Fixes: 50e34d7881 ("block: disable the elevator int del_gendisk")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230414084008.2085155-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This is what about half of the users already want, and it's only going to
grow more.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-16-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
These op vectors are constant, so mark them const.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-15-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Switch to passing a gendisk, and make rq_qos_add initialize all required
fields and drop the not required q argument from rq_qos_del.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-14-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
wbt_queue_depth_changed just updates a field and calls another function.
Open code it in wbt_init, so that the local queue variable can be used
instead of the one stored in the rq_qos. This will allow delaying that
rq_qos->queue assignment in a subsequent patch.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-12-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
A large part of blk-wbt.h is only used in blk-wbt.c, so move it there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-11-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pass a gendisk to wbt_init to prepare for phasing out usage of the
request_queue in the blk-cgroup code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-10-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pass a gendisk to wbt_enable_default and wbt_disable_default to
prepare for phasing out usage of the request_queue in the blk-cgroup
code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Andreas Herrmann <aherrmann@suse.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230203150400.3199230-9-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Commit b5dc5d4d1f ("block,bfq: Disable writeback throttling") tries to
disable wbt for bfq, it's done by calling wbt_disable_default() in
bfq_init_queue(). However, wbt is still enabled if default elevator is
bfq:
device_add_disk
elevator_init_mq
bfq_init_queue
wbt_disable_default -> done nothing
blk_register_queue
wbt_enable_default -> wbt is enabled
Fix the problem by adding a new flag ELEVATOR_FLAG_DISBALE_WBT, bfq
will set the flag in bfq_init_queue, and following wbt_enable_default()
won't enable wbt while the flag is set.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-7-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, if wbt is initialized and then disabled by
wbt_disable_default(), sysfs will still show valid wbt_lat_usec, which
will confuse users that wbt is still enabled.
This patch shows wbt_lat_usec as zero if it's disabled.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reported-and-tested-by: Holger Hoffstätte <holger@applied-asynchrony.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-5-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, if user disable wbt through sysfs, 'enable_state' will be
'WBT_STATE_ON_MANUAL', which will be confusing. Add a new state
'WBT_STATE_OFF_MANUAL' to cover that case.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20221019121518.3865235-4-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
commit 8c5035dfbb ("blk-wbt: call rq_qos_add() after wb_normal is
initialized") moves wbt_set_write_cache() before rq_qos_add(), which
is wrong because wbt_rq_qos() is still NULL.
Fix the problem by removing wbt_set_write_cache() and setting 'rwb->wc'
directly. Noted that this patch also remove the redundant setting of
'rab->wc'.
Fixes: 8c5035dfbb ("blk-wbt: call rq_qos_add() after wb_normal is initialized")
Reported-by: kernel test robot <yujie.liu@intel.com>
Link: https://lore.kernel.org/r/202210081045.77ddf59b-yujie.liu@intel.com
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20221009101038.1692875-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Our test found a problem that wbt inflight counter is negative, which
will cause io hang(noted that this problem doesn't exist in mainline):
t1: device create t2: issue io
add_disk
blk_register_queue
wbt_enable_default
wbt_init
rq_qos_add
// wb_normal is still 0
/*
* in mainline, disk can't be opened before
* bdev_add(), however, in old kernels, disk
* can be opened before blk_register_queue().
*/
blkdev_issue_flush
// disk size is 0, however, it's not checked
submit_bio_wait
submit_bio
blk_mq_submit_bio
rq_qos_throttle
wbt_wait
bio_to_wbt_flags
rwb_enabled
// wb_normal is 0, inflight is not increased
wbt_queue_depth_changed(&rwb->rqos);
wbt_update_limits
// wb_normal is initialized
rq_qos_track
wbt_track
rq->wbt_flags |= bio_to_wbt_flags(rwb, bio);
// wb_normal is not 0，wbt_flags will be set
t3: io completion
blk_mq_free_request
rq_qos_done
wbt_done
wbt_is_tracked
// return true
__wbt_done
wbt_rqw_done
atomic_dec_return(&rqw->inflight);
// inflight is decreased
commit 8235b5c1e8 ("block: call bdev_add later in device_add_disk") can
avoid this problem, however it's better to fix this problem in wbt:
1) Lower kernel can't backport this patch due to lots of refactor.
2) Root cause is that wbt call rq_qos_add() before wb_normal is
initialized.
Fixes: e34cbd3074 ("blk-wbt: add general throttling mechanism")
Cc: <stable@vger.kernel.org>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20220913105749.3086243-1-yukuai1@huaweicloud.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In our test of iocost, we encountered some list add/del corruptions of
inner_walk list in ioc_timer_fn.
The reason can be described as follows:
cpu 0 cpu 1
ioc_qos_write ioc_qos_write
ioc = q_to_ioc(queue);
if (!ioc) {
ioc = kzalloc();
ioc = q_to_ioc(queue);
if (!ioc) {
ioc = kzalloc();
...
rq_qos_add(q, rqos);
}
...
rq_qos_add(q, rqos);
...
}
When the io.cost.qos file is written by two cpus concurrently, rq_qos may
be added to one disk twice. In that case, there will be two iocs enabled
and running on one disk. They own different iocgs on their active list. In
the ioc_timer_fn function, because of the iocgs from two iocs have the
same root iocg, the root iocg's walk_list may be overwritten by each other
and this leads to list add/del corruptions in building or destroying the
inner_walk list.
And so far, the blk-rq-qos framework works in case that one instance for
one type rq_qos per queue by default. This patch make this explicit and
also fix the crash above.
Signed-off-by: Jinke Han <hanjinke.666@bytedance.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20220720093616.70584-1-hanjinke.666@bytedance.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use the new blk_opf_t type for arguments and variables that represent
request flags or a bitwise combination of a request operation and
request flags. Rename the function arguments and also a structure member
that hold a request operation and flags from 'rw' into 'opf'.
This patch does not change any functionality.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-7-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Change the type of the arguments that are used to pass a REQ_OP_* value
from int or unsigned int into enum req_op to improve static type
checking.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Damien Le Moal <damien.lemoal@wdc.com>
Cc: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20220714180729.1065367-3-bvanassche@acm.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace the magic lookup through the kobject tree with an explicit
backpointer, given that the device model links are set up and torn
down at times when I/O is still possible, leading to potential
NULL or invalid pointer dereferences.
Fixes: edb0872f44 ("block: move the bdi from the request_queue to the gendisk")
Reported-by: syzbot <syzbot+aa0801b6b32dca9dda82@syzkaller.appspotmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Sven Schnelle <svens@linux.ibm.com>
Link: https://lore.kernel.org/r/20210816134624.GA24234@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The backing device information only makes sense for file system I/O,
and thus belongs into the gendisk and not the lower level request_queue
structure. Move it there.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20210809141744.1203023-5-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
After commit a79050434b ("blk-rq-qos: refactor out common elements of
blk-wbt"), if throttle was disabled by wbt_disable_default(), we could
not enable again, fix this by set enable_state back to
WBT_STATE_ON_DEFAULT.
Fixes: a79050434b ("blk-rq-qos: refactor out common elements of blk-wbt")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20210619093700.920393-3-yi.zhang@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that we disable wbt by simply zero out rwb->wb_normal in
wbt_disable_default() when switch elevator to bfq, but it's not safe
because it will become false positive if we change queue depth. If it
become false positive between wbt_wait() and wbt_track() when submit
write request, it will lead to drop rqw->inflight to -1 in wbt_done(),
which will end up trigger IO hung. Fix this issue by introduce a new
state which mean the wbt was disabled.
Fixes: a79050434b ("blk-rq-qos: refactor out common elements of blk-wbt")
Signed-off-by: Zhang Yi <yi.zhang@huawei.com>
Link: https://lore.kernel.org/r/20210619093700.920393-2-yi.zhang@huawei.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The first parameter rwb is not used for this function.
So just remove it.
Signed-off-by: Lei Chen <lennychen@tencent.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It's unnecessary to call wbt_update_limits explicitly within wbt_init,
because it will be called in the following function wbt_queue_depth_changed.
Signed-off-by: Lei Chen <lennychen@tencent.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now let's rename __wbt_update_limits to wbt_update_limits after the
previous one is deleted.
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
No one call this function after commit 2af2783f2e ("rq-qos: get rid of
redundant wbt_update_limits()"), so remove it.
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Use tracepoint_string() for string literals that are used in the
wbt_step tracepoint, so that userspace tools can display the string
content.
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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>
wbt already gets queue depth changed notification through
wbt_set_queue_depth(). Generalize it into
rq_qos_ops->queue_depth_changed() so that other rq_qos policies can
easily hook into the events too.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There are 4 users which check if queue is registered, so add one helper
to check it.
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Various block layer files do not have any licensing information at all.
Add SPDX tags for the default kernel GPLv2 license to those.
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This patch avoids that sparse reports the following warnings:
CHECK block/blk-wbt.c
block/blk-wbt.c:600:6: warning: symbol 'wbt_issue' was not declared. Should it be static?
block/blk-wbt.c:620:6: warning: symbol 'wbt_requeue' was not declared. Should it be static?
CC block/blk-wbt.o
block/blk-wbt.c:600:6: warning: no previous prototype for wbt_issue [-Wmissing-prototypes]
void wbt_issue(struct rq_qos *rqos, struct request *rq)
^~~~~~~~~
block/blk-wbt.c:620:6: warning: no previous prototype for wbt_requeue [-Wmissing-prototypes]
void wbt_requeue(struct rq_qos *rqos, struct request *rq)
^~~~~~~~~~~
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This information is helpful to either investigate issues, or understand
wbt's internal behaviour.
Cc: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Omar Sandoval <osandov@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Now that we have rq_qos_wait() in place, convert wbt_wait() over to
using it with it's specific callbacks.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Various spots check for q->mq_ops being non-NULL, but provide
a helper to do this instead.
Where the ->mq_ops != NULL check is redundant, remove it.
Since mq == rq-based now that legacy is gone, get rid of the
queue_is_rq_based() and just use queue_is_mq() everywhere.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This isn't unused, if BFQ is modular we get into trouble.
Fixes: b6676f653f ("block: remove a few unused exports")
Signed-off-by: Jens Axboe <axboe@kernel.dk>
