queue_limits_cancel_update() must only be called if
queue_limits_start_update() is called first. Remove the
queue_limits_cancel_update() calls from the raid*_set_limits() functions
because there is no corresponding queue_limits_start_update() call.
Cc: Christoph Hellwig <hch@lst.de>
Fixes: c6e56cf6b2 ("block: move integrity information into queue_limits")
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/linux-raid/20250212171108.3483150-1-bvanassche@acm.org/
Signed-off-by: Yu Kuai <yukuai@kernel.org>
Currently only stacked devices need to explicitly enable atomic writes by
setting BLK_FEAT_ATOMIC_WRITES_STACKED flag.
This does not work well for device mapper stacking devices, as there many
sets of limits are stacked and what is the 'bottom' and 'top' device can
swapped. This means that BLK_FEAT_ATOMIC_WRITES_STACKED needs to be set
for many queue limits, which is messy.
Generalize enabling atomic writes enabling by ensuring that all devices
must explicitly set a flag - that includes NVMe, SCSI sd, and md raid.
Signed-off-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Mike Snitzer <snitzer@kernel.org>
Link: https://lore.kernel.org/r/20250116170301.474130-2-john.g.garry@oracle.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
There are two BUG reports that raid5 will hang at
bitmap_startwrite([1],[2]), root cause is that bitmap start write and end
write is unbalanced, it's not quite clear where, and while reviewing raid5
code, it's found that bitmap operations can be optimized. For example,
for a 4 disks raid5, with chunksize=8k, if user issue a IO (0 + 48k) to
the array:
┌────────────────────────────────────────────────────────────┐
│chunk 0 │
│ ┌────────────┬─────────────┬─────────────┬────────────┼
│ sh0 │A0: 0 + 4k │A1: 8k + 4k │A2: 16k + 4k │A3: P │
│ ┼────────────┼─────────────┼─────────────┼────────────┼
│ sh1 │B0: 4k + 4k │B1: 12k + 4k │B2: 20k + 4k │B3: P │
┼──────┴────────────┴─────────────┴─────────────┴────────────┼
│chunk 1 │
│ ┌────────────┬─────────────┬─────────────┬────────────┤
│ sh2 │C0: 24k + 4k│C1: 32k + 4k │C2: P │C3: 40k + 4k│
│ ┼────────────┼─────────────┼─────────────┼────────────┼
│ sh3 │D0: 28k + 4k│D1: 36k + 4k │D2: P │D3: 44k + 4k│
└──────┴────────────┴─────────────┴─────────────┴────────────┘
Before this patch, 4 stripe head will be used, and each sh will attach
bio for 3 disks, and each attached bio will trigger
bitmap_startwrite() once, which means total 12 times.
- 3 times (0 + 4k), for (A0, A1 and A2)
- 3 times (4 + 4k), for (B0, B1 and B2)
- 3 times (8 + 4k), for (C0, C1 and C3)
- 3 times (12 + 4k), for (D0, D1 and D3)
After this patch, md upper layer will calculate that IO range (0 + 48k)
is corresponding to the bitmap (0 + 16k), and call bitmap_startwrite()
just once.
Noted that this patch will align bitmap ranges to the chunks, for example,
if user issue a IO (0 + 4k) to array:
- Before this patch, 1 time (0 + 4k), for A0;
- After this patch, 1 time (0 + 8k) for chunk 0;
Usually, one bitmap bit will represent more than one disk chunk, and this
doesn't have any difference. And even if user really created a array
that one chunk contain multiple bits, the overhead is that more data
will be recovered after power failure.
Also remove STRIPE_BITMAP_PENDING since it's not used anymore.
[1] https://lore.kernel.org/all/CAJpMwyjmHQLvm6zg1cmQErttNNQPDAAXPKM3xgTjMhbfts986Q@mail.gmail.com/
[2] https://lore.kernel.org/all/ADF7D720-5764-4AF3-B68E-1845988737AA@flyingcircus.io/
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250109015145.158868-6-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
For the case that IO failed for one rdev, the bit will be mark as NEEDED
in following cases:
1) If badblocks is set and rdev is not faulty;
2) If rdev is faulty;
Case 1) is useless because synchronize data to badblocks make no sense.
Case 2) can be replaced with mddev->degraded.
Also remove R1BIO_Degraded, R10BIO_Degraded and STRIPE_DEGRADED since
case 2) no longer use them.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20250109015145.158868-3-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Pull more block updates from Jens Axboe:
- NVMe pull request via Keith:
- Use correct srcu list traversal (Breno)
- Scatter-gather support for metadata (Keith)
- Fabrics shutdown race condition fix (Nilay)
- Persistent reservations updates (Guixin)
- Add the required bits for MD atomic write support for raid0/1/10
- Correct return value for unknown opcode in ublk
- Fix deadlock with zone revalidation
- Fix for the io priority request vs bio cleanups
- Use the correct unsigned int type for various limit helpers
- Fix for a race in loop
- Cleanup blk_rq_prep_clone() to prevent uninit-value warning and make
it easier for actual humans to read
- Fix potential UAF when iterating tags
- A few fixes for bfq-iosched UAF issues
- Fix for brd discard not decrementing the allocated page count
- Various little fixes and cleanups
* tag 'block-6.13-20242901' of git://git.kernel.dk/linux: (36 commits)
brd: decrease the number of allocated pages which discarded
block, bfq: fix bfqq uaf in bfq_limit_depth()
block: Don't allow an atomic write be truncated in blkdev_write_iter()
mq-deadline: don't call req_get_ioprio from the I/O completion handler
block: Prevent potential deadlock in blk_revalidate_disk_zones()
block: Remove extra part pointer NULLify in blk_rq_init()
nvme: tuning pr code by using defined structs and macros
nvme: introduce change ptpl and iekey definition
block: return bool from get_disk_ro and bdev_read_only
block: remove a duplicate definition for bdev_read_only
block: return bool from blk_rq_aligned
block: return unsigned int from blk_lim_dma_alignment_and_pad
block: return unsigned int from queue_dma_alignment
block: return unsigned int from bdev_io_opt
block: req->bio is always set in the merge code
block: don't bother checking the data direction for merges
block: blk-mq: fix uninit-value in blk_rq_prep_clone and refactor
Revert "block, bfq: merge bfq_release_process_ref() into bfq_put_cooperator()"
md/raid10: Atomic write support
md/raid1: Atomic write support
...
Pull block updates from Jens Axboe:
- NVMe updates via Keith:
- Use uring_cmd helper (Pavel)
- Host Memory Buffer allocation enhancements (Christoph)
- Target persistent reservation support (Guixin)
- Persistent reservation tracing (Guixen)
- NVMe 2.1 specification support (Keith)
- Rotational Meta Support (Matias, Wang, Keith)
- Volatile cache detection enhancment (Guixen)
- MD updates via Song:
- Maintainers update
- raid5 sync IO fix
- Enhance handling of faulty and blocked devices
- raid5-ppl atomic improvement
- md-bitmap fix
- Support for manually defining embedded partition tables
- Zone append fixes and cleanups
- Stop sending the queued requests in the plug list to the driver
->queue_rqs() handle in reverse order.
- Zoned write plug cleanups
- Cleanups disk stats tracking and add support for disk stats for
passthrough IO
- Add preparatory support for file system atomic writes
- Add lockdep support for queue freezing. Already found a bunch of
issues, and some fixes for that are in here. More will be coming.
- Fix race between queue stopping/quiescing and IO queueing
- ublk recovery improvements
- Fix ublk mmap for 64k pages
- Various fixes and cleanups
* tag 'for-6.13/block-20241118' of git://git.kernel.dk/linux: (118 commits)
MAINTAINERS: Update git tree for mdraid subsystem
block: make struct rq_list available for !CONFIG_BLOCK
block/genhd: use seq_put_decimal_ull for diskstats decimal values
block: don't reorder requests in blk_mq_add_to_batch
block: don't reorder requests in blk_add_rq_to_plug
block: add a rq_list type
block: remove rq_list_move
virtio_blk: reverse request order in virtio_queue_rqs
nvme-pci: reverse request order in nvme_queue_rqs
btrfs: validate queue limits
block: export blk_validate_limits
nvmet: add tracing of reservation commands
nvme: parse reservation commands's action and rtype to string
nvmet: report ns's vwc not present
md/raid5: Increase r5conf.cache_name size
block: remove the ioprio field from struct request
block: remove the write_hint field from struct request
nvme: check ns's volatile write cache not present
nvme: add rotational support
nvme: use command set independent id ns if available
...
So that the implementation won't be exposed, and it'll be possible
to invent a new bitmap by replacing bitmap_operations.
Also change the parameter from bitmap to mddev, to avoid access
bitmap outside md-bitmap.c as much as possible. And change the type
of 'success' and 'behind' from int to bool.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-25-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
So that the implementation won't be exposed, and it'll be possible
to invent a new bitmap by replacing bitmap_operations.
Also change the parameter from bitmap to mddev, to avoid access
bitmap outside md-bitmap.c as much as possible. And change the type
of 'behind' from int to bool.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Link: https://lore.kernel.org/r/20240826074452.1490072-24-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
The md driver wants to enforce a number of flags for all devices, even
when not inheriting them from the underlying devices. To make sure these
flags survive the queue_limits_set calls that md uses to update the
queue limits without deriving them form the previous limits add a new
md_init_stacking_limits helper that calls blk_set_stacking_limits and sets
these flags.
Fixes: 1122c0c1cc ("block: move cache control settings out of queue->flags")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20240626142637.300624-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull in block limits branch, which exists as a shared branch for both
the block and SCSI tree.
* for-6.11/block-limits: (26 commits)
block: move integrity information into queue_limits
block: invert the BLK_INTEGRITY_{GENERATE,VERIFY} flags
block: bypass the STABLE_WRITES flag for protection information
block: don't require stable pages for non-PI metadata
block: use kstrtoul in flag_store
block: factor out flag_{store,show} helper for integrity
block: remove the blk_flush_integrity call in blk_integrity_unregister
block: remove the blk_integrity_profile structure
dm-integrity: use the nop integrity profile
md/raid1: don't free conf on raid0_run failure
md/raid0: don't free conf on raid0_run failure
block: initialize integrity buffer to zero before writing it to media
block: add special APIs for run-time disabling of discard and friends
block: remove unused queue limits API
sr: convert to the atomic queue limits API
sd: convert to the atomic queue limits API
sd: cleanup zoned queue limits initialization
sd: factor out a sd_discard_mode helper
sd: simplify the disable case in sd_config_discard
sd: add a sd_disable_write_same helper
...
Move the integrity information into the queue limits so that it can be
set atomically with other queue limits, and that the sysfs changes to
the read_verify and write_generate flags are properly synchronized.
This also allows to provide a more useful helper to stack the integrity
fields, although it still is separate from the main stacking function
as not all stackable devices want to inherit the integrity settings.
Even with that it greatly simplifies the code in md and dm.
Note that the integrity field is moved as-is into the queue limits.
While there are good arguments for removing the separate blk_integrity
structure, this would cause a lot of churn and might better be done at a
later time if desired. However the integrity field in the queue_limits
structure is now unconditional so that various ifdefs can be avoided or
replaced with IS_ENABLED(). Given that tiny size of it that seems like
a worthwhile trade off.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240613084839.1044015-13-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
For different sync_action, sync_thread will use different max_sectors,
see details in md_sync_max_sectors(), currently both md_do_sync() and
pers->sync_request() in eatch iteration have to get the same
max_sectors. Hence pass in max_sectors for pers->sync_request() to
prevent redundant code.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240611132251.1967786-12-yukuai1@huaweicloud.com
Commit cc27b0c78c ("md: fix deadlock between mddev_suspend() and
md_write_start()") aborted md_write_start() with false when mddev is
suspended, which fixed a deadlock if calling mddev_suspend() with
holding reconfig_mutex(). Since mddev_suspend() now includes
lockdep_assert_not_held(), it no longer holds the reconfig_mutex. This
makes previous abort unnecessary. Now, remove unnecessary abort and
change function return value to void.
Signed-off-by: Li Nan <linan122@huawei.com>
Reviewed-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240525185257.3896201-2-linan666@huaweicloud.com
Pull block updates from Jens Axboe:
- MD pull requests via Song:
- Cleanup redundant checks (Yu Kuai)
- Remove deprecated headers (Marc Zyngier, Song Liu)
- Concurrency fixes (Li Lingfeng)
- Memory leak fix (Li Nan)
- Refactor raid1 read_balance (Yu Kuai, Paul Luse)
- Clean up and fix for md_ioctl (Li Nan)
- Other small fixes (Gui-Dong Han, Heming Zhao)
- MD atomic limits (Christoph)
- NVMe pull request via Keith:
- RDMA target enhancements (Max)
- Fabrics fixes (Max, Guixin, Hannes)
- Atomic queue_limits usage (Christoph)
- Const use for class_register (Ricardo)
- Identification error handling fixes (Shin'ichiro, Keith)
- Improvement and cleanup for cached request handling (Christoph)
- Moving towards atomic queue limits. Core changes and driver bits so
far (Christoph)
- Fix UAF issues in aoeblk (Chun-Yi)
- Zoned fix and cleanups (Damien)
- s390 dasd cleanups and fixes (Jan, Miroslav)
- Block issue timestamp caching (me)
- noio scope guarding for zoned IO (Johannes)
- block/nvme PI improvements (Kanchan)
- Ability to terminate long running discard loop (Keith)
- bdev revalidation fix (Li)
- Get rid of old nr_queues hack for kdump kernels (Ming)
- Support for async deletion of ublk (Ming)
- Improve IRQ bio recycling (Pavel)
- Factor in CPU capacity for remote vs local completion (Qais)
- Add shared_tags configfs entry for null_blk (Shin'ichiro
- Fix for a regression in page refcounts introduced by the folio
unification (Tony)
- Misc fixes and cleanups (Arnd, Colin, John, Kunwu, Li, Navid,
Ricardo, Roman, Tang, Uwe)
* tag 'for-6.9/block-20240310' of git://git.kernel.dk/linux: (221 commits)
block: partitions: only define function mac_fix_string for CONFIG_PPC_PMAC
block/swim: Convert to platform remove callback returning void
cdrom: gdrom: Convert to platform remove callback returning void
block: remove disk_stack_limits
md: remove mddev->queue
md: don't initialize queue limits
md/raid10: use the atomic queue limit update APIs
md/raid5: use the atomic queue limit update APIs
md/raid1: use the atomic queue limit update APIs
md/raid0: use the atomic queue limit update APIs
md: add queue limit helpers
md: add a mddev_is_dm helper
md: add a mddev_add_trace_msg helper
md: add a mddev_trace_remap helper
bcache: move calculation of stripe_size and io_opt into bcache_device_init
virtio_blk: Do not use disk_set_max_open/active_zones()
aoe: fix the potential use-after-free problem in aoecmd_cfg_pkts
block: move capacity validation to blkpg_do_ioctl()
block: prevent division by zero in blk_rq_stat_sum()
drbd: atomically update queue limits in drbd_reconsider_queue_parameters
...
If resync is in progress, read_balance() should find the first usable
disk, otherwise, data could be inconsistent after resync is done. raid1
and raid10 implement the same checking, hence factor out the checking
to make code cleaner.
Noted that raid1 is using 'mddev->recovery_cp', which is updated after
all resync IO is done, while raid10 is using 'conf->next_resync', which
is inaccurate because raid10 update it before submitting resync IO.
Fortunately, raid10 read IO can't concurrent with resync IO, hence there
is no problem. And this patch also switch raid10 to use
'mddev->recovery_cp'.
Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-7-yukuai1@huaweicloud.com
The current api is_badblock() must pass in 'first_bad' and
'bad_sectors', however, many caller just want to know if there are
badblocks or not, and these caller must define two local variable that
will never be used.
Add a new helper rdev_has_badblock() that will only return if there are
badblocks or not, remove unnecessary local variables and replace
is_badblock() with the new helper in many places.
There are no functional changes, and the new helper will also be used
later to refactor read_balance().
Co-developed-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Paul Luse <paul.e.luse@linux.intel.com>
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240229095714.926789-2-yukuai1@huaweicloud.com
Currently, if reshape is interrupted, then reassemble the array will
register sync_thread directly from pers->run(), in this case
'MD_RECOVERY_RUNNING' is set directly, however, there is no guarantee
that md_do_sync() will be executed, hence stop_sync_thread() will hang
because 'MD_RECOVERY_RUNNING' can't be cleared.
Last patch make sure that md_do_sync() will set MD_RECOVERY_DONE,
however, following hang can still be triggered by dm-raid test
shell/lvconvert-raid-reshape.sh occasionally:
[root@fedora ~]# cat /proc/1982/stack
[<0>] stop_sync_thread+0x1ab/0x270 [md_mod]
[<0>] md_frozen_sync_thread+0x5c/0xa0 [md_mod]
[<0>] raid_presuspend+0x1e/0x70 [dm_raid]
[<0>] dm_table_presuspend_targets+0x40/0xb0 [dm_mod]
[<0>] __dm_destroy+0x2a5/0x310 [dm_mod]
[<0>] dm_destroy+0x16/0x30 [dm_mod]
[<0>] dev_remove+0x165/0x290 [dm_mod]
[<0>] ctl_ioctl+0x4bb/0x7b0 [dm_mod]
[<0>] dm_ctl_ioctl+0x11/0x20 [dm_mod]
[<0>] vfs_ioctl+0x21/0x60
[<0>] __x64_sys_ioctl+0xb9/0xe0
[<0>] do_syscall_64+0xc6/0x230
[<0>] entry_SYSCALL_64_after_hwframe+0x6c/0x74
Meanwhile mddev->recovery is:
MD_RECOVERY_RUNNING |
MD_RECOVERY_INTR |
MD_RECOVERY_RESHAPE |
MD_RECOVERY_FROZEN
Fix this problem by remove the code to register sync_thread directly
from raid10 and raid5. And let md_check_recovery() to register
sync_thread.
Fixes: f67055780c ("[PATCH] md: Checkpoint and allow restart of raid5 reshape")
Fixes: f52f5c71f3 ("md: fix stopping sync thread")
Cc: stable@vger.kernel.org # v6.7+
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20240201092559.910982-5-yukuai1@huaweicloud.com
Because it's safe to accees rdev from conf:
- If any spinlock is held, because synchronize_rcu() from
md_kick_rdev_from_array() will prevent 'rdev' to be freed until
spinlock is released;
- If 'reconfig_lock' is held, because rdev can't be added or removed from
array;
- If there is normal IO inflight, because mddev_suspend() will prevent
rdev to be added or removed from array;
- If there is sync IO inflight, because 'MD_RECOVERY_RUNNING' is
checked in remove_and_add_spares().
And these will cover all the scenarios in raid10.
This patch also cleanup the code to handle the case that replacement
replace rdev while IO is still inflight.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231125081604.3939938-3-yukuai1@huaweicloud.com
rcu is not used correctly here, because synchronize_rcu() is called
before replacing old value, for example:
remove_and_add_spares // other path
synchronize_rcu
// called before replacing old value
set_bit(RemoveSynchronized)
rcu_read_lock()
rdev = conf->mirros[].rdev
pers->hot_remove_disk
conf->mirros[].rdev = NULL;
if (!test_bit(RemoveSynchronized))
synchronize_rcu
/*
* won't be called, and won't wait
* for concurrent readers to be done.
*/
// access rdev after remove_and_add_spares()
rcu_read_unlock()
Fortunately, there is a separate rcu protection to prevent such rdev
to be freed:
md_kick_rdev_from_array //other path
rcu_read_lock()
rdev = conf->mirros[].rdev
list_del_rcu(&rdev->same_set)
rcu_read_unlock()
/*
* rdev can be removed from conf, but
* rdev won't be freed.
*/
synchronize_rcu()
free rdev
Hence remove this useless flag and prepare to remove rcu protection to
access rdev from 'conf'.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20231125081604.3939938-2-yukuai1@huaweicloud.com
Currently 'writes_pending' is initialized in pers->run for raid1/5/10,
and it's freed while deleing mddev, instead of pers->free. pers->run can
be called multiple times before mddev is deleted, and a helper
mddev_init_writes_pending() is used to prevent 'writes_pending' to be
initialized multiple times, this usage is safe but a litter weird.
On the other hand, 'writes_pending' is only initialized for raid1/5/10,
however, it's used in common layer, for example:
array_state_store
set_in_sync
if (!mddev->in_sync) -> in_sync is used for all levels
// access writes_pending
There might be some implicit dependency that I don't recognized to make
sure 'writes_pending' can only be accessed for raid1/5/10, but there are
no comments about that.
By the way, it make sense to initialize 'writes_pending' in common layer
because there are already three levels use it.
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230825030956.1527023-3-yukuai1@huaweicloud.com
After commit b39f35ebe8 ("md: don't quiesce in mddev_suspend()"),
'conf->barrier' will be leaked in the case that raid10 takeover raid0:
level_store
pers->takeover -> raid10_takeover
raid10_takeover_raid0
WRITE_ONCE(conf->barrier, 1)
mddev_suspend
// still raid0
mddev->pers = pers
// switch to raid10
mddev_resume
// resume without suspend
After the above commit, mddev_resume() will not decrease 'conf->barrier'
that is set in raid10_takeover_raid0().
Fix this problem by not setting 'conf->barrier' in raid10_takeover_raid0().
By the way, this problem is found while I'm trying to make
mddev_suspend/resume() to be independent from raid personalities. raid10
is the only personality to use reference count in the quiesce() callback
and this problem is only related to raid10.
Fixes: b39f35ebe8 ("md: don't quiesce in mddev_suspend()")
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Reviewed-by: Paul Menzel <pmenzel@molgen.mpg.de>
Link: https://lore.kernel.org/r/20230731022800.1424902-1-yukuai1@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Commit 2ae6aaf769 ("md/raid10: fix io loss while replacement replace
rdev") reads replacement first to prevent io loss. However, there are same
issue in wait_blocked_dev() and raid10_handle_discard(), too. Fix it by
using dereference_rdev_and_rrdev() to get devices.
Fixes: d30588b273 ("md/raid10: improve raid10 discard request")
Fixes: f2e7e269a7 ("md/raid10: pull the code that wait for blocked dev into one function")
Signed-off-by: Li Nan <linan122@huawei.com>
Link: https://lore.kernel.org/r/20230701080529.2684932-4-linan666@huaweicloud.com
Signed-off-by: Song Liu <song@kernel.org>
Commit 0c0be98bbe ("md/raid10: prevent unnecessary calls to wake_up()
in fast path") missed one place, for example, with:
fio -direct=1 -rw=write/randwrite -iodepth=1 ...
Plug and unplug are called for each io, then wake_up() from raid10_unplug()
will cause lock contention as well.
Avoid this contention by using wake_up_barrier() instead of wake_up(),
where spin_lock is not held if waitqueue is empty.
Fio test script:
[global]
name=random reads and writes
ioengine=libaio
direct=1
readwrite=randrw
rwmixread=70
iodepth=64
buffered=0
filename=/dev/md0
size=1G
runtime=30
time_based
randrepeat=0
norandommap
refill_buffers
ramp_time=10
bs=4k
numjobs=400
group_reporting=1
[job1]
Test result with ramdisk raid10(By Ali):
Before this patch With this patch
READ IOPS=2033k IOPS=3642k
WRITE IOPS=871k IOPS=1561K
By the way, in this scenario, blk_plug_cb() will be allocated and freed
for each io, this seems need to be optimized as well.
Reported-and-tested-by: Ali Gholami Rudi <aligrudi@gmail.com>
Closes: https://lore.kernel.org/all/20231606122233@laper.mirepesht/
Signed-off-by: Yu Kuai <yukuai3@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230621105728.1268542-1-yukuai1@huaweicloud.com
/sys/block/[device]/queue/iostats is used to control whether to count io
stat. Write 0 to it will clear queue_flags QUEUE_FLAG_IO_STAT which means
iostats is disabled. If we disable iostats and later endable it, the io
issued during this period will be counted incorrectly, inflight will be
decreased to -1.
//T1 set iostats
echo 0 > /sys/block/md0/queue/iostats
clear QUEUE_FLAG_IO_STAT
//T2 issue io
if (QUEUE_FLAG_IO_STAT) -> false
bio_start_io_acct
inflight++
echo 1 > /sys/block/md0/queue/iostats
set QUEUE_FLAG_IO_STAT
//T3 io end
if (QUEUE_FLAG_IO_STAT) -> true
bio_end_io_acct
inflight-- -> -1
Also, if iostats is enabled while issuing io but disabled while io end,
inflight will never be decreased.
Fix it by checking start_time when io end. If start_time is not 0, call
bio_end_io_acct().
Fixes: 528bc2cf2f ("md/raid10: enable io accounting")
Signed-off-by: Li Nan <linan122@huawei.com>
Signed-off-by: Song Liu <song@kernel.org>
Link: https://lore.kernel.org/r/20230609094320.2397604-1-linan666@huaweicloud.com
