Refactor raid5_read_one_chunk so that all simple checks are done
before allocating the bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Replace the gendisk pointer in struct bio with a pointer to the newly
improved struct block device. From that the gendisk can be trivially
accessed with an extra indirection, but it also allows to directly
look up all information related to partition remapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The request_queue can trivially be derived from the bio.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When try to resize stripe_size, we also need to free old
shared page array and allocate new.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
When reshape array, we try to reuse shared pages of old stripe_head,
and allocate more for the new one if needed.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
In current implementation, grow_buffers() uses alloc_page() to
allocate the buffers for each stripe_head, i.e. allocate a page
for each dev[i] in stripe_head.
After setting stripe_size as a configurable value by writing
sysfs entry, it means that we always allocate 64K buffers, but
just use 4K of them when stripe_size is 4K in 64KB arm64.
To avoid wasting memory, we try to let multiple sh->dev share
one real page. That means, multiple sh->dev[i].page will point
to the only page with different offset. Example of 64K PAGE_SIZE
and 4K stripe_size as following:
64K PAGE_SIZE
+---+---+---+---+------------------------------+
| | | | |
| | | | |
+-+-+-+-+-+-+-+-+------------------------------+
^ ^ ^ ^
| | | +----------------------------+
| | | |
| | +-------------------+ |
| | | |
| +----------+ | |
| | | |
+-+ | | |
| | | |
+-----+-----+------+-----+------+-----+------+------+
sh | offset(0) | offset(4K) | offset(8K) | offset(12K) |
+ +-----------+------------+------------+-------------+
+----> dev[0].page dev[1].page dev[2].page dev[3].page
A new 'pages' array will be added into stripe_head to record shared
page used by this stripe_head. Allocate them when grow_buffers()
and free them when shrink_buffers().
After trying to share page, the users of sh->dev[i].page need to take
care of the related page offset: page of issued bio and page passed
to xor compution functions. But thanks for previous different page offset
supported. Here, we just need to set correct dev[i].offset.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
For now, asynchronous raid6 recovery calculate functions are require
common offset for pages. But, we expect them to support different page
offset after introducing stripe shared page. Do that by simplily adding
page offset where each page address are referred. Then, replace the
old interface with the new ones in raid6 and raid6test.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
For now, syndrome compute functions require common offset in the pages
array. However, we expect them to support different offset when try to
use shared page in the following. Simplily covert them by adding page
offset where each page address are referred.
Since the only caller of async_gen_syndrome() and async_syndrome_val()
are in raid6, we don't want to reserve the old interface but modify the
interface directly. After that, replacing old interfaces with new ones
for raid6 and raid6test.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
We try to replace async_xor() and async_xor_val() with the new
introduced interface async_xor_offs() and async_xor_val_offs()
for raid456.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
ops_run_biofill() and ops_run_biodrain() will call async_copy_data()
to copy sh->dev[i].page from or to bio page. For now, it implies the
offset of dev[i].page is 0. But we want to support different page offset
in the following.
Thus, pass page offset to these functions and replace 'page_offset'
with 'page_offset + poff'.
No functional change.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Add a new member of offset into struct r5dev. It indicates the
offset of related dev[i].page. For now, since each device have a
privated page, the value is always 0. Thus, we set offset as 0
when allcate page in grow_buffers() and resize_stripes().
To support following different page offset, we try to use the page
offset rather than '0' directly for async_memcpy() and ops_run_io().
We try to support different page offset for xor compution functions
in the following. To avoid repeatly allocate a new array each time,
we add a memory region into scribble buffer to record offset.
No functional change.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
The BDI_CAP_STABLE_WRITES is one of the few bits of information in the
backing_dev_info shared between the block drivers and the writeback code.
To help untangling the dependency replace it with a queue flag and a
superblock flag derived from it. This also helps with the case of e.g.
a file system requiring stable writes due to its own checksumming, but
not forcing it on other users of the block device like the swap code.
One downside is that we an't support the stable_pages_required bdi
attribute in sysfs anymore. It is replaced with a queue attribute which
also is writable for easier testing.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Drivers shouldn't really mess with the readahead size, as that is a VM
concept. Instead set it based on the optimal I/O size by lifting the
algorithm from the md driver when registering the disk. Also set
bdi->io_pages there as well by applying the same scheme based on
max_sectors. To ensure the limits work well for stacking drivers a
new helper is added to update the readahead limits from the block
limits, which is also called from disk_stack_limits.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The raid5 and raid10 drivers currently update the read-ahead size,
but not the optimal I/O size on reshape. To prepare for deriving the
read-ahead size from the optimal I/O size make sure it is updated
as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
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Merge tag 'block-5.9-2020-08-28' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
- nbd timeout fix (Hou)
- device size fix for loop LOOP_CONFIGURE (Martijn)
- MD pull from Song with raid5 stripe size fix (Yufen)
* tag 'block-5.9-2020-08-28' of git://git.kernel.dk/linux-block:
md/raid5: make sure stripe_size as power of two
loop: Set correct device size when using LOOP_CONFIGURE
nbd: restore default timeout when setting it to zero
Commit 3b5408b98e ("md/raid5: support config stripe_size by sysfs
entry") make stripe_size as a configurable value. It just requires
stripe_size as multiple of 4KB.
In fact, we should make sure stripe_size as power of two. Otherwise,
stripe_shift which is the result of ilog2 can not represent the real
stripe_size. Then, stripe_hash() and stripe_hash_locks_hash() may
get unexpected value.
Fixes: 3b5408b98e ("md/raid5: support config stripe_size by sysfs entry")
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
- Untangle the header spaghetti which causes build failures in various
situations caused by the lockdep additions to seqcount to validate that
the write side critical sections are non-preemptible.
- The seqcount associated lock debug addons which were blocked by the
above fallout.
seqcount writers contrary to seqlock writers must be externally
serialized, which usually happens via locking - except for strict per
CPU seqcounts. As the lock is not part of the seqcount, lockdep cannot
validate that the lock is held.
This new debug mechanism adds the concept of associated locks.
sequence count has now lock type variants and corresponding
initializers which take a pointer to the associated lock used for
writer serialization. If lockdep is enabled the pointer is stored and
write_seqcount_begin() has a lockdep assertion to validate that the
lock is held.
Aside of the type and the initializer no other code changes are
required at the seqcount usage sites. The rest of the seqcount API is
unchanged and determines the type at compile time with the help of
_Generic which is possible now that the minimal GCC version has been
moved up.
Adding this lockdep coverage unearthed a handful of seqcount bugs which
have been addressed already independent of this.
While generaly useful this comes with a Trojan Horse twist: On RT
kernels the write side critical section can become preemtible if the
writers are serialized by an associated lock, which leads to the well
known reader preempts writer livelock. RT prevents this by storing the
associated lock pointer independent of lockdep in the seqcount and
changing the reader side to block on the lock when a reader detects
that a writer is in the write side critical section.
- Conversion of seqcount usage sites to associated types and initializers.
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Merge tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Thomas Gleixner:
"A set of locking fixes and updates:
- Untangle the header spaghetti which causes build failures in
various situations caused by the lockdep additions to seqcount to
validate that the write side critical sections are non-preemptible.
- The seqcount associated lock debug addons which were blocked by the
above fallout.
seqcount writers contrary to seqlock writers must be externally
serialized, which usually happens via locking - except for strict
per CPU seqcounts. As the lock is not part of the seqcount, lockdep
cannot validate that the lock is held.
This new debug mechanism adds the concept of associated locks.
sequence count has now lock type variants and corresponding
initializers which take a pointer to the associated lock used for
writer serialization. If lockdep is enabled the pointer is stored
and write_seqcount_begin() has a lockdep assertion to validate that
the lock is held.
Aside of the type and the initializer no other code changes are
required at the seqcount usage sites. The rest of the seqcount API
is unchanged and determines the type at compile time with the help
of _Generic which is possible now that the minimal GCC version has
been moved up.
Adding this lockdep coverage unearthed a handful of seqcount bugs
which have been addressed already independent of this.
While generally useful this comes with a Trojan Horse twist: On RT
kernels the write side critical section can become preemtible if
the writers are serialized by an associated lock, which leads to
the well known reader preempts writer livelock. RT prevents this by
storing the associated lock pointer independent of lockdep in the
seqcount and changing the reader side to block on the lock when a
reader detects that a writer is in the write side critical section.
- Conversion of seqcount usage sites to associated types and
initializers"
* tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
locking/seqlock, headers: Untangle the spaghetti monster
locking, arch/ia64: Reduce <asm/smp.h> header dependencies by moving XTP bits into the new <asm/xtp.h> header
x86/headers: Remove APIC headers from <asm/smp.h>
seqcount: More consistent seqprop names
seqcount: Compress SEQCNT_LOCKNAME_ZERO()
seqlock: Fold seqcount_LOCKNAME_init() definition
seqlock: Fold seqcount_LOCKNAME_t definition
seqlock: s/__SEQ_LOCKDEP/__SEQ_LOCK/g
hrtimer: Use sequence counter with associated raw spinlock
kvm/eventfd: Use sequence counter with associated spinlock
userfaultfd: Use sequence counter with associated spinlock
NFSv4: Use sequence counter with associated spinlock
iocost: Use sequence counter with associated spinlock
raid5: Use sequence counter with associated spinlock
vfs: Use sequence counter with associated spinlock
timekeeping: Use sequence counter with associated raw spinlock
xfrm: policy: Use sequence counters with associated lock
netfilter: nft_set_rbtree: Use sequence counter with associated rwlock
netfilter: conntrack: Use sequence counter with associated spinlock
sched: tasks: Use sequence counter with associated spinlock
...
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Merge tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block
Pull block driver updates from Jens Axboe:
- NVMe:
- ZNS support (Aravind, Keith, Matias, Niklas)
- Misc cleanups, optimizations, fixes (Baolin, Chaitanya, David,
Dongli, Max, Sagi)
- null_blk zone capacity support (Aravind)
- MD:
- raid5/6 fixes (ChangSyun)
- Warning fixes (Damien)
- raid5 stripe fixes (Guoqing, Song, Yufen)
- sysfs deadlock fix (Junxiao)
- raid10 deadlock fix (Vitaly)
- struct_size conversions (Gustavo)
- Set of bcache updates/fixes (Coly)
* tag 'for-5.9/drivers-20200803' of git://git.kernel.dk/linux-block: (117 commits)
md/raid5: Allow degraded raid6 to do rmw
md/raid5: Fix Force reconstruct-write io stuck in degraded raid5
raid5: don't duplicate code for different paths in handle_stripe
raid5-cache: hold spinlock instead of mutex in r5c_journal_mode_show
md: print errno in super_written
md/raid5: remove the redundant setting of STRIPE_HANDLE
md: register new md sysfs file 'uuid' read-only
md: fix max sectors calculation for super 1.0
nvme-loop: remove extra variable in create ctrl
nvme-loop: set ctrl state connecting after init
nvme-multipath: do not fall back to __nvme_find_path() for non-optimized paths
nvme-multipath: fix logic for non-optimized paths
nvme-rdma: fix controller reset hang during traffic
nvme-tcp: fix controller reset hang during traffic
nvmet: introduce the passthru Kconfig option
nvmet: introduce the passthru configfs interface
nvmet: Add passthru enable/disable helpers
nvmet: add passthru code to process commands
nvme: export nvme_find_get_ns() and nvme_put_ns()
nvme: introduce nvme_ctrl_get_by_path()
...
Degraded raid6 always do reconstruct-write now. With raid6 xor supported,
we can do rmw in degraded raid6. This patch can reduce many read IOs to
improve performance.
If the failed disk is P, Q or the disk we want to write to, we may need to
do reconstruct-write in max degraded raid6. In this situation we can not
read enough data from handle_stripe_dirtying() so we have to set force_rcw
in handle_stripe_fill() to read all data.
Reviewed-by: Alex Wu <alexwu@synology.com>
Reviewed-by: BingJing Chang <bingjingc@synology.com>
Reviewed-by: Danny Shih <dannyshih@synology.com>
Signed-off-by: ChangSyun Peng <allenpeng@synology.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
In degraded raid5, we need to read parity to do reconstruct-write when
data disks fail. However, we can not read parity from
handle_stripe_dirtying() in force reconstruct-write mode.
Reproducible Steps:
1. Create degraded raid5
mdadm -C /dev/md2 --assume-clean -l5 -n3 /dev/sda2 /dev/sdb2 missing
2. Set rmw_level to 0
echo 0 > /sys/block/md2/md/rmw_level
3. IO to raid5
Now some io may be stuck in raid5. We can use handle_stripe_fill() to read
the parity in this situation.
Cc: <stable@vger.kernel.org> # v4.4+
Reviewed-by: Alex Wu <alexwu@synology.com>
Reviewed-by: BingJing Chang <bingjingc@synology.com>
Reviewed-by: Danny Shih <dannyshih@synology.com>
Signed-off-by: ChangSyun Peng <allenpeng@synology.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
As we can see, R5_LOCKED is set and s.locked is increased whether
R5_ReWrite is set or not, so move it to common path.
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
The flag is already set before compare rcw with rmw, so it is
not necessary to do it again.
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
A sequence counter write side critical section must be protected by some
form of locking to serialize writers. A plain seqcount_t does not
contain the information of which lock must be held when entering a write
side critical section.
Use the new seqcount_spinlock_t data type, which allows to associate a
spinlock with the sequence counter. This enables lockdep to verify that
the spinlock used for writer serialization is held when the write side
critical section is entered.
If lockdep is disabled this lock association is compiled out and has
neither storage size nor runtime overhead.
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Song Liu <song@kernel.org>
Link: https://lkml.kernel.org/r/20200720155530.1173732-20-a.darwish@linutronix.de
We get compilation error on 32-bit architectures (e.g. m68k), as:
ERROR: modpost: "__udivdi3" [drivers/md/raid456.ko] undefined!
Since 'sync_blocks' is defined as u64, use do_div() to fix this error.
Fixes: c911c46c01 ("md/raid456: convert macro STRIPE_* to RAID5_STRIPE_*")
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Adding a new 'stripe_size' sysfs entry to set and show stripe_size.
stripe_size should not be bigger than PAGE_SIZE, and it requires to
be multiple of 4096. We can adjust stripe_size by writing value into
sysfs entry, likely, set stripe_size as 16KB:
echo 16384 > /sys/block/md1/md/stripe_size
Show current stripe_size value:
cat /sys/block/md1/md/stripe_size
For PAGE_SIZE is equal to 4096, 'stripe_size' can just be read.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
In RAID5, if issued bio size is bigger than stripe_size, it will be
split in the unit of stripe_size and process them one by one. Even
for size less then stripe_size, RAID5 also request data from disk at
least of stripe_size.
Nowdays, stripe_size is equal to the value of PAGE_SIZE. Since filesystem
usually issue bio in the unit of 4KB, there is no problem for PAGE_SIZE
as 4KB. But, for 64KB PAGE_SIZE, bio from filesystem requests 4KB data
while RAID5 issue IO at least stripe_size (64KB) each time. That will
waste resource of disk bandwidth and compute xor.
To avoding the waste, we want to make stripe_size configurable. This
patch just set default stripe_size as 4096. User can also set the value
bigger than 4KB for some special requirements, such as we know the
issued io size is more than 4KB.
To evaluate the new feature, we create raid5 device '/dev/md5' with
4 SSD disk and test it on arm64 machine with 64KB PAGE_SIZE.
1) We format /dev/md5 with mkfs.ext4 and mount ext4 with default
configure on /mnt directory. Then, trying to test it by dbench with
command: dbench -D /mnt -t 1000 10. Result show as:
'stripe_size = 64KB'
Operation Count AvgLat MaxLat
----------------------------------------
NTCreateX 9805011 0.021 64.728
Close 7202525 0.001 0.120
Rename 415213 0.051 44.681
Unlink 1980066 0.079 93.147
Deltree 240 1.793 6.516
Mkdir 120 0.004 0.007
Qpathinfo 8887512 0.007 37.114
Qfileinfo 1557262 0.001 0.030
Qfsinfo 1629582 0.012 0.152
Sfileinfo 798756 0.040 57.641
Find 3436004 0.019 57.782
WriteX 4887239 0.021 57.638
ReadX 15370483 0.005 37.818
LockX 31934 0.003 0.022
UnlockX 31933 0.001 0.021
Flush 687205 13.302 530.088
Throughput 307.799 MB/sec 10 clients 10 procs max_latency=530.091 ms
-------------------------------------------------------
'stripe_size = 4KB'
Operation Count AvgLat MaxLat
----------------------------------------
NTCreateX 11999166 0.021 36.380
Close 8814128 0.001 0.122
Rename 508113 0.051 29.169
Unlink 2423242 0.070 38.141
Deltree 300 1.885 7.155
Mkdir 150 0.004 0.006
Qpathinfo 10875921 0.007 35.485
Qfileinfo 1905837 0.001 0.032
Qfsinfo 1994304 0.012 0.125
Sfileinfo 977450 0.029 26.489
Find 4204952 0.019 9.361
WriteX 5981890 0.019 27.804
ReadX 18809742 0.004 33.491
LockX 39074 0.003 0.025
UnlockX 39074 0.001 0.014
Flush 841022 10.712 458.848
Throughput 376.777 MB/sec 10 clients 10 procs max_latency=458.852 ms
-------------------------------------------------------
It show that setting stripe_size as 4KB has higher thoughput, i.e.
(376.777 vs 307.799) and has smaller latency than that setting as 64KB.
2) We try to evaluate IO throughput for /dev/md5 by fio with config:
[4KB randwrite]
direct=1
numjob=2
iodepth=64
ioengine=libaio
filename=/dev/md5
bs=4KB
rw=randwrite
[64KB write]
direct=1
numjob=2
iodepth=64
ioengine=libaio
filename=/dev/md5
bs=1MB
rw=write
The result as follow:
+ +
| stripe_size(64KB) | stripe_size(4KB)
+----------------------------------------------------+
4KB randwrite | 15MB/s | 100MB/s
+----------------------------------------------------+
1MB write | 1000MB/s | 700MB/s
The result show that when size of io is bigger than 4KB (64KB),
64KB stripe_size has much higher IOPS. But for 4KB randwrite, that
means, size of io issued to device are smaller, 4KB stripe_size
have better performance.
Normally, default value (4096) can get relatively good performance.
But if each issued io is bigger than 4096, setting value more than
4096 may get better performance.
Here, we just set default stripe_size as 4096, and we will try to
support setting different stripe_size by sysfs interface in the
following patch.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Convert macro STRIPE_SIZE, STRIPE_SECTORS and STRIPE_SHIFT to
RAID5_STRIPE_SIZE(), RAID5_STRIPE_SECTORS() and RAID5_STRIPE_SHIFT().
This patch is prepare for the following adjustable stripe_size.
It will not change any existing functionality.
Signed-off-by: Yufen Yu <yuyufen@huawei.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.
In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:
git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
xargs perl -pi -e \
's/\buninitialized_var\(([^\)]+)\)/\1/g;
s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'
drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.
No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.
[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/
Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
We can't guarntee the batched stripe to be set with STRIPE_HANDLE since
there are lots of functions could set the flag, such as sync_request,
ops_complete_* and end_{read,write}_request etc.
Also clear_batch_ready called in handle_stripe ensures the batched list
can't continue to be handled by handle_stripe.
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
To make people understand the function well, let's put the comment to
the right place.
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
We tried to only put the head sh of batch list to handle_list, then the
handle_stripe doesn't handle other members in the batch list. However,
we still got the calltrace in break_stripe_batch_list.
[593764.644269] stripe state: 2003
kernel: [593764.644299] ------------[ cut here ]------------
kernel: [593764.644308] WARNING: CPU: 12 PID: 856 at drivers/md/raid5.c:4625 break_stripe_batch_list+0x203/0x240 [raid456]
[...]
kernel: [593764.644363] Call Trace:
kernel: [593764.644370] handle_stripe+0x907/0x20c0 [raid456]
kernel: [593764.644376] ? __wake_up_common_lock+0x89/0xc0
kernel: [593764.644379] handle_active_stripes.isra.57+0x35f/0x570 [raid456]
kernel: [593764.644382] ? raid5_wakeup_stripe_thread+0x96/0x1f0 [raid456]
kernel: [593764.644385] raid5d+0x480/0x6a0 [raid456]
kernel: [593764.644390] ? md_thread+0x11f/0x160
kernel: [593764.644392] md_thread+0x11f/0x160
kernel: [593764.644394] ? wait_woken+0x80/0x80
kernel: [593764.644396] kthread+0xfc/0x130
kernel: [593764.644398] ? find_pers+0x70/0x70
kernel: [593764.644399] ? kthread_create_on_node+0x70/0x70
kernel: [593764.644401] ret_from_fork+0x1f/0x30
As we can see, the stripe was set with STRIPE_ACTIVE and STRIPE_HANDLE,
and only handle_stripe could set those flags then return. And since the
stipe was already in the batch list, we need to return earlier before
set the two flags.
And after dig a little about git history especially commit 3664847d95
("md/raid5: fix a race condition in stripe batch"), it seems the batched
stipe still could be handled by handle_stipe, then handle_stipe needs to
return earlier if clear_batch_ready to return true.
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Remove the if statement around the calls to sysfs_link_rdev() to avoid
the compilation warning "suggest braces around empty body in an ‘if’
statement" when compiling with W=1.
Also fix function description comments to avoid kdoc format warnings.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
The following deadlock was captured. The first process is holding 'kernfs_mutex'
and hung by io. The io was staging in 'r1conf.pending_bio_list' of raid1 device,
this pending bio list would be flushed by second process 'md127_raid1', but
it was hung by 'kernfs_mutex'. Using sysfs_notify_dirent_safe() to replace
sysfs_notify() can fix it. There were other sysfs_notify() invoked from io
path, removed all of them.
PID: 40430 TASK: ffff8ee9c8c65c40 CPU: 29 COMMAND: "probe_file"
#0 [ffffb87c4df37260] __schedule at ffffffff9a8678ec
#1 [ffffb87c4df372f8] schedule at ffffffff9a867f06
#2 [ffffb87c4df37310] io_schedule at ffffffff9a0c73e6
#3 [ffffb87c4df37328] __dta___xfs_iunpin_wait_3443 at ffffffffc03a4057 [xfs]
#4 [ffffb87c4df373a0] xfs_iunpin_wait at ffffffffc03a6c79 [xfs]
#5 [ffffb87c4df373b0] __dta_xfs_reclaim_inode_3357 at ffffffffc039a46c [xfs]
#6 [ffffb87c4df37400] xfs_reclaim_inodes_ag at ffffffffc039a8b6 [xfs]
#7 [ffffb87c4df37590] xfs_reclaim_inodes_nr at ffffffffc039bb33 [xfs]
#8 [ffffb87c4df375b0] xfs_fs_free_cached_objects at ffffffffc03af0e9 [xfs]
#9 [ffffb87c4df375c0] super_cache_scan at ffffffff9a287ec7
#10 [ffffb87c4df37618] shrink_slab at ffffffff9a1efd93
#11 [ffffb87c4df37700] shrink_node at ffffffff9a1f5968
#12 [ffffb87c4df37788] do_try_to_free_pages at ffffffff9a1f5ea2
#13 [ffffb87c4df377f0] try_to_free_mem_cgroup_pages at ffffffff9a1f6445
#14 [ffffb87c4df37880] try_charge at ffffffff9a26cc5f
#15 [ffffb87c4df37920] memcg_kmem_charge_memcg at ffffffff9a270f6a
#16 [ffffb87c4df37958] new_slab at ffffffff9a251430
#17 [ffffb87c4df379c0] ___slab_alloc at ffffffff9a251c85
#18 [ffffb87c4df37a80] __slab_alloc at ffffffff9a25635d
#19 [ffffb87c4df37ac0] kmem_cache_alloc at ffffffff9a251f89
#20 [ffffb87c4df37b00] alloc_inode at ffffffff9a2a2b10
#21 [ffffb87c4df37b20] iget_locked at ffffffff9a2a4854
#22 [ffffb87c4df37b60] kernfs_get_inode at ffffffff9a311377
#23 [ffffb87c4df37b80] kernfs_iop_lookup at ffffffff9a311e2b
#24 [ffffb87c4df37ba8] lookup_slow at ffffffff9a290118
#25 [ffffb87c4df37c10] walk_component at ffffffff9a291e83
#26 [ffffb87c4df37c78] path_lookupat at ffffffff9a293619
#27 [ffffb87c4df37cd8] filename_lookup at ffffffff9a2953af
#28 [ffffb87c4df37de8] user_path_at_empty at ffffffff9a295566
#29 [ffffb87c4df37e10] vfs_statx at ffffffff9a289787
#30 [ffffb87c4df37e70] SYSC_newlstat at ffffffff9a289d5d
#31 [ffffb87c4df37f18] sys_newlstat at ffffffff9a28a60e
#32 [ffffb87c4df37f28] do_syscall_64 at ffffffff9a003949
#33 [ffffb87c4df37f50] entry_SYSCALL_64_after_hwframe at ffffffff9aa001ad
RIP: 00007f617a5f2905 RSP: 00007f607334f838 RFLAGS: 00000246
RAX: ffffffffffffffda RBX: 00007f6064044b20 RCX: 00007f617a5f2905
RDX: 00007f6064044b20 RSI: 00007f6064044b20 RDI: 00007f6064005890
RBP: 00007f6064044aa0 R8: 0000000000000030 R9: 000000000000011c
R10: 0000000000000013 R11: 0000000000000246 R12: 00007f606417e6d0
R13: 00007f6064044aa0 R14: 00007f6064044b10 R15: 00000000ffffffff
ORIG_RAX: 0000000000000006 CS: 0033 SS: 002b
PID: 927 TASK: ffff8f15ac5dbd80 CPU: 42 COMMAND: "md127_raid1"
#0 [ffffb87c4df07b28] __schedule at ffffffff9a8678ec
#1 [ffffb87c4df07bc0] schedule at ffffffff9a867f06
#2 [ffffb87c4df07bd8] schedule_preempt_disabled at ffffffff9a86825e
#3 [ffffb87c4df07be8] __mutex_lock at ffffffff9a869bcc
#4 [ffffb87c4df07ca0] __mutex_lock_slowpath at ffffffff9a86a013
#5 [ffffb87c4df07cb0] mutex_lock at ffffffff9a86a04f
#6 [ffffb87c4df07cc8] kernfs_find_and_get_ns at ffffffff9a311d83
#7 [ffffb87c4df07cf0] sysfs_notify at ffffffff9a314b3a
#8 [ffffb87c4df07d18] md_update_sb at ffffffff9a688696
#9 [ffffb87c4df07d98] md_update_sb at ffffffff9a6886d5
#10 [ffffb87c4df07da8] md_check_recovery at ffffffff9a68ad9c
#11 [ffffb87c4df07dd0] raid1d at ffffffffc01f0375 [raid1]
#12 [ffffb87c4df07ea0] md_thread at ffffffff9a680348
#13 [ffffb87c4df07f08] kthread at ffffffff9a0b8005
#14 [ffffb87c4df07f50] ret_from_fork at ffffffff9aa00344
Signed-off-by: Junxiao Bi <junxiao.bi@oracle.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Except for pktdvd, the only places setting congested bits are file
systems that allocate their own backing_dev_info structures. And
pktdvd is a deprecated driver that isn't useful in stack setup
either. So remove the dead congested_fn stacking infrastructure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Song Liu <song@kernel.org>
Acked-by: David Sterba <dsterba@suse.com>
[axboe: fixup unused variables in bcache/request.c]
Signed-off-by: Jens Axboe <axboe@kernel.dk>
generic_make_request has always been very confusingly misnamed, so rename
it to submit_bio_noacct to make it clear that it is submit_bio minus
accounting and a few checks.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Code comments of scribble_alloc() is outdated for a while. This patch
update the comments in function header for the new parameter list.
Suggested-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
Using GFP_NOIO flag to call scribble_alloc() from resize_chunk() does
not have the expected behavior. kvmalloc_array() inside scribble_alloc()
which receives the GFP_NOIO flag will eventually call kmalloc_node() to
allocate physically continuous pages.
Now we have memalloc scope APIs in mddev_suspend()/mddev_resume() to
prevent memory reclaim I/Os during raid array suspend context, calling
to kvmalloc_array() with GFP_KERNEL flag may avoid deadlock of recursive
I/O as expected.
This patch removes the useless gfp flags from parameters list of
scribble_alloc(), and call kvmalloc_array() with GFP_KERNEL flag. The
incorrect GFP_NOIO flag does not exist anymore.
Fixes: b330e6a49d ("md: convert to kvmalloc")
Suggested-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Song Liu <songliubraving@fb.com>
We can use "cnt" directly to update conf->worker_cnt_per_group
if alloc_thread_groups returns 0.
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
With commit 6ce220dd2f ("raid5: don't set
STRIPE_HANDLE to stripe which is in batch list"), we don't want to set
STRIPE_HANDLE flag for sh which is already in batch list.
However, the stripe which is the head of batch list should set this flag,
otherwise panic could happen inside init_stripe at BUG_ON(sh->batch_head),
it is reproducible with raid5 on top of nvdimm devices per Xiao oberserved.
Thanks for Xiao's effort to verify the change.
Fixes: 6ce220dd2f ("raid5: don't set STRIPE_HANDLE to stripe which is in batch list")
Reported-by: Xiao Ni <xni@redhat.com>
Tested-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
As it is consistent with prefixes of other write life time hints.
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
If pers->make_request fails in md_flush_request(), the bio is lost. To
fix this, pass back a bool to indicate if the original make_request call
should continue to handle the I/O and instead of assuming the flush logic
will push it to completion.
Convert md_flush_request to return a bool and no longer calls the raid
driver's make_request function. If the return is true, then the md flush
logic has or will complete the bio and the md make_request call is done.
If false, then the md make_request function needs to keep processing like
it is a normal bio. Let the original call to md_handle_request handle any
need to retry sending the bio to the raid driver's make_request function
should it be needed.
Also mark md_flush_request and the make_request function pointer as
__must_check to issue warnings should these critical return values be
ignored.
Fixes: 2bc13b83e6 ("md: batch flush requests.")
Cc: stable@vger.kernel.org # # v4.19+
Cc: NeilBrown <neilb@suse.com>
Signed-off-by: David Jeffery <djeffery@redhat.com>
Reviewed-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
This stripe state is not used anymore after commit 51acbcec6c
("md: remove CONFIG_MULTICORE_RAID456"), so remove the obsoleted
state.
gjiang@nb01257:~/md$ grep STRIPE_OPS_REQ_PENDING drivers/md/ -r
drivers/md/raid5.c: (1 << STRIPE_OPS_REQ_PENDING) |
drivers/md/raid5.h: STRIPE_OPS_REQ_PENDING,
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
If stripe in batch list is set with STRIPE_HANDLE flag, then the stripe
could be set with STRIPE_ACTIVE by the handle_stripe function. And if
error happens to the batch_head at the same time, break_stripe_batch_list
is called, then below warning could happen (the same report in [1]), it
means a member of batch list was set with STRIPE_ACTIVE.
[7028915.431770] stripe state: 2001
[7028915.431815] ------------[ cut here ]------------
[7028915.431828] WARNING: CPU: 18 PID: 29089 at drivers/md/raid5.c:4614 break_stripe_batch_list+0x203/0x240 [raid456]
[...]
[7028915.431879] CPU: 18 PID: 29089 Comm: kworker/u82:5 Tainted: G O 4.14.86-1-storage #4.14.86-1.2~deb9
[7028915.431881] Hardware name: Supermicro SSG-2028R-ACR24L/X10DRH-iT, BIOS 3.1 06/18/2018
[7028915.431888] Workqueue: raid5wq raid5_do_work [raid456]
[7028915.431890] task: ffff9ab0ef36d7c0 task.stack: ffffb72926f84000
[7028915.431896] RIP: 0010:break_stripe_batch_list+0x203/0x240 [raid456]
[7028915.431898] RSP: 0018:ffffb72926f87ba8 EFLAGS: 00010286
[7028915.431900] RAX: 0000000000000012 RBX: ffff9aaa84a98000 RCX: 0000000000000000
[7028915.431901] RDX: 0000000000000000 RSI: ffff9ab2bfa15458 RDI: ffff9ab2bfa15458
[7028915.431902] RBP: ffff9aaa8fb4e900 R08: 0000000000000001 R09: 0000000000002eb4
[7028915.431903] R10: 00000000ffffffff R11: 0000000000000000 R12: ffff9ab1736f1b00
[7028915.431904] R13: 0000000000000000 R14: ffff9aaa8fb4e900 R15: 0000000000000001
[7028915.431906] FS: 0000000000000000(0000) GS:ffff9ab2bfa00000(0000) knlGS:0000000000000000
[7028915.431907] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[7028915.431908] CR2: 00007ff953b9f5d8 CR3: 0000000bf4009002 CR4: 00000000003606e0
[7028915.431909] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[7028915.431910] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[7028915.431910] Call Trace:
[7028915.431923] handle_stripe+0x8e7/0x2020 [raid456]
[7028915.431930] ? __wake_up_common_lock+0x89/0xc0
[7028915.431935] handle_active_stripes.isra.58+0x35f/0x560 [raid456]
[7028915.431939] raid5_do_work+0xc6/0x1f0 [raid456]
Also commit 59fc630b8b ("RAID5: batch adjacent full stripe write")
said "If a stripe is added to batch list, then only the first stripe
of the list should be put to handle_list and run handle_stripe."
So don't set STRIPE_HANDLE to stripe which is already in batch list,
otherwise the stripe could be put to handle_list and run handle_stripe,
then the above warning could be triggered.
[1]. https://www.spinics.net/lists/raid/msg62552.html
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
While MD continues to count read errors returned by the lower layer.
If those errors are -EILSEQ, instead of -EIO, it should NOT increase
the read_errors count.
When RAID6 is set up on dm-integrity target that detects massive
corruption, the leg will be ejected from the array. Even if the
issue is correctable with a sector re-write and the array has
necessary redundancy to correct it.
The leg is ejected because it runs up the rdev->read_errors beyond
conf->max_nr_stripes. The return status in dm-drypt when there is
a data integrity error is -EILSEQ (BLK_STS_PROTECTION).
Signed-off-by: Nigel Croxon <ncroxon@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Often limits can be changed by admin. When discussing such things
it helps if you can provide "self-sustained" facts. Also
sometimes the admin thinks he changed a limit, but it did not
take effect for some reason or he changed the wrong thing.
V3: Only pr_warn when Faulty is 0.
V2: Add read_errors value to pr_warn.
Signed-off-by: Nigel Croxon <ncroxon@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
7471fb77ce ("md/raid6: Fix anomily when recovering a single device in
RAID6.") avoids rereading P when it can be computed from other members.
However, this misses the chance to re-write the right data to P. This
patch sets R5_ReadError if the re-read fails.
Also, when re-read is skipped, we also missed the chance to reset
rdev->read_errors to 0. It can fail the disk when there are many read
errors on P member disk (other disks don't have read error)
V2: upper layer read request don't read parity/Q data. So there is no
need to consider such situation.
This is Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 7471fb77ce ("md/raid6: Fix anomily when recovering a single device in RAID6.")
Cc: <stable@vger.kernel.org> #4.4+
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Christoph Hellwig
Song Liu
Yufen Yu
Linus Torvalds
Gustavo A. R. Silva
ChangSyun Peng
Guoqing Jiang
Ahmed S. Darwish
Kees Cook
Damien Le Moal
Junxiao Bi
Coly Li
Eugene Syromiatnikov
David Jeffery
Nigel Croxon
Guoqing Jiang
Xiao Ni