For safer operation, all arrays start in write-through mode, which has been
better tested and is more mature. And actually the write-through/write-mode
isn't persistent after array restarted, so we always start array in
write-through mode. However, if recovery found data-only stripes before the
shutdown (from previous write-back mode), it is not safe to start the array in
write-through mode, as write-through mode can not handle stripes with data in
write-back cache. To solve this problem, we flush all data-only stripes in
r5l_recovery_log(). When r5l_recovery_log() returns, the array starts with
empty cache in write-through mode.
This logic is implemented in r5c_recovery_flush_data_only_stripes():
1. enable write back cache
2. flush all stripes
3. wake up conf->mddev->thread
4. wait for all stripes get flushed (reuse wait_for_quiescent)
5. disable write back cache
The wait in 4 will be waked up in release_inactive_stripe_list()
when conf->active_stripes reaches 0.
It is safe to wake up mddev->thread here because all the resource
required for the thread has been initialized.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Pull block layer updates from Jens Axboe:
"This is the main block pull request this series. Contrary to previous
release, I've kept the core and driver changes in the same branch. We
always ended up having dependencies between the two for obvious
reasons, so makes more sense to keep them together. That said, I'll
probably try and keep more topical branches going forward, especially
for cycles that end up being as busy as this one.
The major parts of this pull request is:
- Improved support for O_DIRECT on block devices, with a small
private implementation instead of using the pig that is
fs/direct-io.c. From Christoph.
- Request completion tracking in a scalable fashion. This is utilized
by two components in this pull, the new hybrid polling and the
writeback queue throttling code.
- Improved support for polling with O_DIRECT, adding a hybrid mode
that combines pure polling with an initial sleep. From me.
- Support for automatic throttling of writeback queues on the block
side. This uses feedback from the device completion latencies to
scale the queue on the block side up or down. From me.
- Support from SMR drives in the block layer and for SD. From Hannes
and Shaun.
- Multi-connection support for nbd. From Josef.
- Cleanup of request and bio flags, so we have a clear split between
which are bio (or rq) private, and which ones are shared. From
Christoph.
- A set of patches from Bart, that improve how we handle queue
stopping and starting in blk-mq.
- Support for WRITE_ZEROES from Chaitanya.
- Lightnvm updates from Javier/Matias.
- Supoort for FC for the nvme-over-fabrics code. From James Smart.
- A bunch of fixes from a whole slew of people, too many to name
here"
* 'for-4.10/block' of git://git.kernel.dk/linux-block: (182 commits)
blk-stat: fix a few cases of missing batch flushing
blk-flush: run the queue when inserting blk-mq flush
elevator: make the rqhash helpers exported
blk-mq: abstract out blk_mq_dispatch_rq_list() helper
blk-mq: add blk_mq_start_stopped_hw_queue()
block: improve handling of the magic discard payload
blk-wbt: don't throttle discard or write zeroes
nbd: use dev_err_ratelimited in io path
nbd: reset the setup task for NBD_CLEAR_SOCK
nvme-fabrics: Add FC LLDD loopback driver to test FC-NVME
nvme-fabrics: Add target support for FC transport
nvme-fabrics: Add host support for FC transport
nvme-fabrics: Add FC transport LLDD api definitions
nvme-fabrics: Add FC transport FC-NVME definitions
nvme-fabrics: Add FC transport error codes to nvme.h
Add type 0x28 NVME type code to scsi fc headers
nvme-fabrics: patch target code in prep for FC transport support
nvme-fabrics: set sqe.command_id in core not transports
parser: add u64 number parser
nvme-rdma: align to generic ib_event logging helper
...
The mddev->flags are used for different purposes. There are a lot of
places we check/change the flags without masking unrelated flags, we
could check/change unrelated flags. These usage are most for superblock
write, so spearate superblock related flags. This should make the code
clearer and also fix real bugs.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
md_open() gets a counted reference on an mddev using mddev_find().
If it ends up returning an error, it must drop this reference.
There are two error paths where the reference is not dropped.
One only happens if the process is signalled and an awkward time,
which is quite unlikely.
The other was introduced recently in commit af8d8e6f0.
Change the code to ensure the drop the reference when returning an error,
and make it harded to re-introduce this sort of bug in the future.
Reported-by: Marc Smith <marc.smith@mcc.edu>
Fixes: af8d8e6f03 ("md: changes for MD_STILL_CLOSED flag")
Signed-off-by: NeilBrown <neilb@suse.com>
Acked-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
__md_stop_writes currently doesn't stop raid5-cache reclaim thread. It's
possible the reclaim thread is still running and doing write, which
doesn't match what __md_stop_writes should do. The extra ->quiesce()
call should not harm any raid types. For raid5-cache, this will
guarantee we reclaim all caches before we update superblock.
Signed-off-by: Shaohua Li <shli@fb.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Cc: Song Liu <songliubraving@fb.com>
There is mechanism to suspend a kernel thread. Use it instead of playing
create/destroy game.
Signed-off-by: Shaohua Li <shli@fb.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Cc: Song Liu <songliubraving@fb.com>
This can only be supported on personalities which ensure
that md_error() never causes an array to enter the 'failed'
state. i.e. if marking a device Faulty would cause some
data to be inaccessible, the device is status is left as
non-Faulty. This is true for RAID1 and RAID10.
If we get a failure writing metadata but the device doesn't
fail, it must be the last device so we re-write without
FAILFAST to improve chance of success. We also flag the
device as LastDev so that future metadata updates don't
waste time on failfast writes.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This patch just adds a 'failfast' per-device flag which can be stored
in v0.90 or v1.x metadata.
The flag is not used yet but the intent is that it can be used for
mirrored (raid1/raid10) arrays where low latency is more important
than keeping all devices on-line.
Setting the flag for a device effectively gives permission for that
device to be marked as Faulty and excluded from the array on the first
error. The underlying driver will be directed not to retry requests
that result in failures. There is a proviso that the device must not
be marked faulty if that would cause the array as a whole to fail, it
may only be marked Faulty if the array remains functional, but is
degraded.
Failures on read requests will cause the device to be marked
as Faulty immediately so that further reads will avoid that
device. No attempt will be made to correct read errors by
over-writing with the correct data.
It is expected that if transient errors, such as cable unplug, are
possible, then something in user-space will revalidate failed
devices and re-add them when they appear to be working again.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
superblock write is an expensive operation. With raid5-cache, it can be called
regularly. Tracing to help performance debug.
Signed-off-by: Shaohua Li <shli@fb.com>
Cc: NeilBrown <neilb@suse.com>
bitmap_flush() finishes with bitmap_update_sb(), and that finishes
with write_page(..., 1), so write_page() will wait for all writes
to complete. So there is no point calling md_super_wait()
immediately afterwards.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When adding devices to, or removing device from, an array we need to
update the metadata. However we don't need to do it synchronously as
data integrity doesn't depend on these changes being recorded
instantly. So avoid the synchronous call to md_update_sb and just set
a flag so that the thread will do it.
This can reduce the number of updates performed when lots of devices
are being added or removed.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
1/ using pr_debug() for a number of messages reduces the noise of
md, but still allows them to be enabled when needed.
2/ try to be consistent in the usage of pr_err() and pr_warn(), and
document the intention
3/ When strings have been split onto multiple lines, rejoin into
a single string.
The cost of having lines > 80 chars is less than the cost of not
being able to easily search for a particular message.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
1/ don't print a warning if allocation fails.
page_alloc() does that already.
2/ always check return status for error.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When raid1/raid10 array fails to write to one of the drives, the request
is added to bio_end_io_list and finished by personality thread. The
thread doesn't handle it as long as MD_CHANGE_PENDING flag is set. In
case of external metadata this flag is cleared, however the thread is
not woken up. It causes request to be blocked for few seconds (until
another action on the array wakes up the thread) or to get stuck
indefinitely.
Wake up personality thread once MD_CHANGE_PENDING has been cleared.
Moving 'restart_array' call after the flag is cleared it not a solution
because in read-write mode the call doesn't wake up the thread.
Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
If external metadata handler supports bad blocks and unacknowledged bad
blocks are present, don't report disk via sysfs as faulty. Such
situation can be still handled so disk just has to be blocked for a
moment. It makes it consistent with kernel state as corresponding rdev
flag is also not set.
When the disk in being unblocked there are few cases:
1. Disk has been in blocked and faulty state, it is being unblocked but
it still remains in faulty state. Metadata handler will remove it from
array in the next call.
2. There is no bad block support in external metadata handler and bad
blocks are present - put the disk in blocked and faulty state (see
case 1).
3. There is bad block support in external metadata handler and all bad
blocks are acknowledged - clear all flags, continue.
4. There is bad block support in external metadata handler but there are
still unacknowledged bad blocks - clear all flags, continue. It is fine
to clear Blocked flag because it was probably not set anyway (if it was
it is case 1). BlockedBadBlocks flag can also be cleared because the
request waiting for it will set it again when it finds out that some bad
block is still not acknowledged. Recovery is not necessary but there are
no problems if the flag is set. Sysfs rdev state is still reported as
blocked (due to unacknowledged bad blocks) so metadata handler will
process remaining bad blocks and unblock disk again.
Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Add new rdev flag which external metadata handler can use to switch
on/off bad block support. If new bad block is encountered, notify it via
rdev 'unacknowledged_bad_blocks' sysfs file. If bad block has been
cleared, notify update to rdev 'bad_blocks' sysfs file.
When bad blocks support is being removed, just clear rdev flag. It is
not necessary to reset badblocks->shift field. If there are bad blocks
cleared or added at the same time, it is ok for those changes to be
applied to the structure. The array is in blocked state and the drive
which cannot handle bad blocks any more will be removed from the array
before it is unlocked.
Simplify state_show function by adding a separator at the end of each
string and overwrite last separator with new line.
Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
Reviewed-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Remove the WRITE_* and READ_SYNC wrappers, and just use the flags
directly. Where applicable this also drops usage of the
bio_set_op_attrs wrapper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
mddev->curr_resync usually records where the current resync is up to,
but during the starting phase it has some "magic" values.
1 - means that the array is trying to start a resync, but has yielded
to another array which shares physical devices, and also needs to
start a resync
2 - means the array is trying to start resync, but has found another
array which shares physical devices and has already started resync.
3 - means that resync has commensed, but it is possible that nothing
has actually been resynced yet.
It is important that this value not be visible to user-space and
particularly that it doesn't get written to the metadata, as the
resync or recovery checkpoint. In part, this is because it may be
slightly higher than the correct value, though this is very rare.
In part, because it is not a multiple of 4K, and some devices only
support 4K aligned accesses.
There are two places where this value is propagates into either
->curr_resync_completed or ->recovery_cp or ->recovery_offset.
These currently avoid the propagation of values 1 and 3, but will
allow 3 to leak through.
Change them to only propagate the value if it is > 3.
As this can cause an array to fail, the patch is suitable for -stable.
Cc: stable@vger.kernel.org (v3.7+)
Reported-by: Viswesh <viswesh.vichu@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
If there is a bad block on a disk and there is a recovery performed from
this disk, the same bad block is reported for a new disk. It involves
setting MD_CHANGE_PENDING flag in rdev_set_badblocks. For external
metadata this flag is not being cleared as array state is reported as
'clean'. The read request to bad block in RAID5 array gets stuck as it
is waiting for a flag to be cleared - as per commit c3cce6cda1
("md/raid5: ensure device failure recorded before write request
returns.").
The meaning of MD_CHANGE_PENDING and MD_CHANGE_CLEAN flags has been
clarified in commit 070dc6dd71 ("md: resolve confusion of
MD_CHANGE_CLEAN"), however MD_CHANGE_PENDING flag has been used in
personality error handlers since and it doesn't fully comply with
initial purpose. It was supposed to notify that write request is about
to start, however now it is also used to request metadata update.
Initially (in md_allow_write, md_write_start) MD_CHANGE_PENDING flag has
been set and in_sync has been set to 0 at the same time. Error handlers
just set the flag without modifying in_sync value. Sysfs array state is
a single value so now it reports 'clean' when MD_CHANGE_PENDING flag is
set and in_sync is set to 1. Userspace has no idea it is expected to
take some action.
Swap the order that array state is checked so 'write_pending' is
reported ahead of 'clean' ('write_pending' is a misleading name but it
is too late to rename it now).
Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
if all disks in an array are non-rotational, set the array
non-rotational.
This only works for array with all disks populated at startup. Support
for disk hotadd/hotremove could be added later if necessary.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Shaohua Li <shli@fb.com>
cluster_info and bitmap_info.nodes also need to be
cleared when array is stopped.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When stop clustered raid while it is pending on resync,
MD_STILL_CLOSED flag could be cleared since udev rule
is triggered to open the mddev. So obviously array can't
be stopped soon and returns EBUSY.
mdadm -Ss md-raid-arrays.rules
set MD_STILL_CLOSED md_open()
... ... ... clear MD_STILL_CLOSED
do_md_stop
We make below changes to resolve this issue:
1. rename MD_STILL_CLOSED to MD_CLOSING since it is set
when stop array and it means we are stopping array.
2. let md_open returns early if CLOSING is set, so no
other threads will open array if one thread is trying
to close it.
3. no need to clear CLOSING bit in md_open because 1 has
ensure the bit is cleared, then we also don't need to
test CLOSING bit in do_md_stop.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The new_disk_ack could return failure if WAITING_FOR_NEWDISK
is not set, so we need to kick the dev from array in case
failure happened.
And we missed to check err before call new_disk_ack othwise
we could kick a rdev which isn't in array, thanks for the
reminder from Shaohua.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The md-cluster is compiled as module by default,
if it is compiled by built-in way, then we can't
make md-cluster works.
[64782.630008] md/raid1:md127: active with 2 out of 2 mirrors
[64782.630528] md-cluster module not found.
[64782.630530] md127: Could not setup cluster service (-2)
Fixes: edb39c9 ("Introduce md_cluster_operations to handle cluster functions")
Cc: stable@vger.kernel.org (v4.1+)
Reported-by: Marc Smith <marc.smith@mcc.edu>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Pull MD fixes from Shaohua Li:
"This includes several bug fixes:
- Alexey Obitotskiy fixed a hang for faulty raid5 array with external
management
- Song Liu fixed two raid5 journal related bugs
- Tomasz Majchrzak fixed a bad block recording issue and an
accounting issue for raid10
- ZhengYuan Liu fixed an accounting issue for raid5
- I fixed a potential race condition and memory leak with DIF/DIX
enabled
- other trival fixes"
* tag 'md/4.8-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
raid5: avoid unnecessary bio data set
raid5: fix memory leak of bio integrity data
raid10: record correct address of bad block
md-cluster: fix error return code in join()
r5cache: set MD_JOURNAL_CLEAN correctly
md: don't print the same repeated messages about delayed sync operation
md: remove obsolete ret in md_start_sync
md: do not count journal as spare in GET_ARRAY_INFO
md: Prevent IO hold during accessing to faulty raid5 array
MD: hold mddev lock to change bitmap location
raid5: fix incorrectly counter of conf->empty_inactive_list_nr
raid10: increment write counter after bio is split
Currently, the code sets MD_JOURNAL_CLEAN when the array has
MD_FEATURE_JOURNAL and the recovery_cp is MaxSector. The array
will be MD_JOURNAL_CLEAN even if the journal device is missing.
With this patch, the MD_JOURNAL_CLEAN is only set when the journal
device presents.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This fixes a long-standing bug that caused a flood of messages like:
"md: delaying data-check of md1 until md2 has finished (they share one
or more physical units)"
It can be reproduced like this:
1. Create at least 3 raid1 arrays on a pair of disks, each on different
partitions.
2. Request a sync operation like 'check' or 'repair' on 2 arrays by
writing to their md/sync_action attribute files. One operation should
start and one should be delayed and a message like the above will be
printed.
3. Issue a write to the third array. Each write will cause 2 copies of
the message to be printed.
This happens when wake_up(&resync_wait) is called, usually by
md_check_recovery(). Then the delayed sync thread again prints the
message and is put to sleep. This patch adds a check in md_do_sync() to
prevent printing this message more than once for the same pair of
devices.
Reported-by: Sven Koehler <sven.koehler@gmail.com>
Link: https://bugzilla.kernel.org/show_bug.cgi?id=151801
Signed-off-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The ret is not needed anymore since we have already
move resync_start into md_do_sync in commit 41a9a0d.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
GET_ARRAY_INFO counts journal as spare (spare_disks), which is not
accurate. This patch fixes this.
Reported-by: Yi Zhang <yizhan@redhat.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Since commit 63a4cc2486, bio->bi_rw contains flags in the lower
portion and the op code in the higher portions. This means that
old code that relies on manually setting bi_rw is most likely
going to be broken. Instead of letting that brokeness linger,
rename the member, to force old and out-of-tree code to break
at compile time instead of at runtime.
No intended functional changes in this commit.
Signed-off-by: Jens Axboe <axboe@fb.com>
The md device might not have personality (for example, ddf raid array). The
issue is introduced by 8430e7e0af9a15(md: disconnect device from personality
before trying to remove it)
Reported-by: kernel test robot <xiaolong.ye@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Changeset 6791875e2e has added early return from a function so there is no
sysfs notification for 'active' and 'clean' state change.
Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
md loads raidX modules and increments module refcount each time level
has changed but does not decrement it. You are unable to unload raid0
module after reshape because raid0 reshape changes level to raid4
and back to raid0.
Signed-off-by: Aleksey Obitotskiy <aleksey.obitotskiy@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The md code stores the exact time of the last error in the
last_read_error variable using a timespec structure. It only
ever uses the seconds portion of that though, so we can
use a scalar for it.
There won't be an overflow in 2038 here, because it already
used monotonic time and 32-bit is enough for that, but I've
decided to use time64_t for consistency in the conversion.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Shaohua Li <shli@fb.com>
Every time a device is removed with ->hot_remove_disk() a synchronize_rcu() call is made
which can delay several milliseconds in some case.
If lots of devices fail at once - as could happen with a large RAID10 where one set
of devices are removed all at once - these delays can add up to be very inconcenient.
As failure is not reversible we can check for that first, setting a
separate flag if it is found, and then all synchronize_rcu() once for
all the flagged devices. Then ->hot_remove_disk() function can skip the
synchronize_rcu() step if the flag is set.
fix build error(Shaohua)
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When the HOT_REMOVE_DISK ioctl is used to remove a device, we
call remove_and_add_spares() which will remove it from the personality
if possible. This improves the chances that the removal will succeed.
When writing "remove" to dev-XX/state, we don't. So that can fail more easily.
So add the remove_and_add_spares() into "remove" handling.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This is a simple check before updating the superblock. It should update
the superblock when update_size return 0.
Signed-off-by: Xiao Ni <xni@redhat.com>
Signed-off-by: Shaohua Li <shli@fb.com>
To avoid confusion between REQ_OP_FLUSH, which is handled by
request_fn drivers, and upper layers requesting the block layer
perform a flush sequence along with possibly a WRITE, this patch
renames REQ_FLUSH to REQ_PREFLUSH.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Separate the op from the rq_flag_bits and have md
set/get the bio using bio_set_op_attrs/bio_op.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This has callers of submit_bio/submit_bio_wait set the bio->bi_rw
instead of passing it in. This makes that use the same as
generic_make_request and how we set the other bio fields.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Fixed up fs/ext4/crypto.c
Signed-off-by: Jens Axboe <axboe@fb.com>
Add a disk to an array which is performing recovery
is a little complicated, we need to do both reap the
sync thread and perform add disk for the case, then
it caused deadlock as follows.
linux44:~ # ps aux|grep md|grep D
root 1822 0.0 0.0 0 0 ? D 16:50 0:00 [md127_resync]
root 1848 0.0 0.0 19860 952 pts/0 D+ 16:50 0:00 mdadm --manage /dev/md127 --re-add /dev/vdb
linux44:~ # cat /proc/1848/stack
[<ffffffff8107afde>] kthread_stop+0x6e/0x120
[<ffffffffa051ddb0>] md_unregister_thread+0x40/0x80 [md_mod]
[<ffffffffa0526e45>] md_reap_sync_thread+0x15/0x150 [md_mod]
[<ffffffffa05271e0>] action_store+0x260/0x270 [md_mod]
[<ffffffffa05206b4>] md_attr_store+0xb4/0x100 [md_mod]
[<ffffffff81214a7e>] sysfs_write_file+0xbe/0x140
[<ffffffff811a6b98>] vfs_write+0xb8/0x1e0
[<ffffffff811a75b8>] SyS_write+0x48/0xa0
[<ffffffff8152a5c9>] system_call_fastpath+0x16/0x1b
[<00007f068ea1ed30>] 0x7f068ea1ed30
linux44:~ # cat /proc/1822/stack
[<ffffffffa05251a6>] md_do_sync+0x846/0xf40 [md_mod]
[<ffffffffa052402d>] md_thread+0x16d/0x180 [md_mod]
[<ffffffff8107ad94>] kthread+0xb4/0xc0
[<ffffffff8152a518>] ret_from_fork+0x58/0x90
Task1848 Task1822
md_attr_store (held reconfig_mutex by call mddev_lock())
action_store
md_reap_sync_thread
md_unregister_thread
kthread_stop md_wakeup_thread(mddev->thread);
wait_event(mddev->sb_wait, !test_bit(MD_CHANGE_PENDING))
md_check_recovery is triggered by wakeup mddev->thread,
but it can't clear MD_CHANGE_PENDING flag since it can't
get lock which was held by md_attr_store already.
To solve the deadlock problem, we move "->resync_finish()"
from md_do_sync to md_reap_sync_thread (after md_update_sb),
also MD_HELD_RESYNC_LOCK is introduced since it is possible
that node can't get resync lock in md_do_sync.
Then we do not need to wait for MD_CHANGE_PENDING is cleared
or not since metadata should be updated after md_update_sb,
so just call resync_finish if MD_HELD_RESYNC_LOCK is set.
We also unified the code after skip label, since set PENDING
for non-clustered case should be harmless.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Pull MD updates from Shaohua Li:
"Several patches from Guoqing fixing md-cluster bugs and several
patches from Heinz fixing dm-raid bugs"
* tag 'md/4.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
md-cluster: check the return value of process_recvd_msg
md-cluster: gather resync infos and enable recv_thread after bitmap is ready
md: set MD_CHANGE_PENDING in a atomic region
md: raid5: add prerequisite to run underneath dm-raid
md: raid10: add prerequisite to run underneath dm-raid
md: md.c: fix oops in mddev_suspend for raid0
md-cluster: fix ifnullfree.cocci warnings
md-cluster/bitmap: unplug bitmap to sync dirty pages to disk
md-cluster/bitmap: fix wrong page num in bitmap_file_clear_bit and bitmap_file_set_bit
md-cluster/bitmap: fix wrong calcuation of offset
md-cluster: sync bitmap when node received RESYNCING msg
md-cluster: always setup in-memory bitmap
md-cluster: wakeup thread if activated a spare disk
md-cluster: change array_sectors and update size are not supported
md-cluster: fix locking when node joins cluster during message broadcast
md-cluster: unregister thread if err happened
md-cluster: wake up thread to continue recovery
md-cluser: make resync_finish only called after pers->sync_request
md-cluster: change resync lock from asynchronous to synchronous
Pull block driver updates from Jens Axboe:
"On top of the core pull request, this is the drivers pull request for
this merge window. This contains:
- Switch drivers to the new write back cache API, and kill off the
flush flags. From me.
- Kill the discard support for the STEC pci-e flash driver. It's
trivially broken, and apparently unmaintained, so it's safer to
just remove it. From Jeff Moyer.
- A set of lightnvm updates from the usual suspects (Matias/Javier,
and Simon), and fixes from Arnd, Jeff Mahoney, Sagi, and Wenwei
Tao.
- A set of updates for NVMe:
- Turn the controller state management into a proper state
machine. From Christoph.
- Shuffling of code in preparation for NVMe-over-fabrics, also
from Christoph.
- Cleanup of the command prep part from Ming Lin.
- Rewrite of the discard support from Ming Lin.
- Deadlock fix for namespace removal from Ming Lin.
- Use the now exported blk-mq tag helper for IO termination.
From Sagi.
- Various little fixes from Christoph, Guilherme, Keith, Ming
Lin, Wang Sheng-Hui.
- Convert mtip32xx to use the now exported blk-mq tag iter function,
from Keith"
* 'for-4.7/drivers' of git://git.kernel.dk/linux-block: (74 commits)
lightnvm: reserved space calculation incorrect
lightnvm: rename nr_pages to nr_ppas on nvm_rq
lightnvm: add is_cached entry to struct ppa_addr
lightnvm: expose gennvm_mark_blk to targets
lightnvm: remove mgt targets on mgt removal
lightnvm: pass dma address to hardware rather than pointer
lightnvm: do not assume sequential lun alloc.
nvme/lightnvm: Log using the ctrl named device
lightnvm: rename dma helper functions
lightnvm: enable metadata to be sent to device
lightnvm: do not free unused metadata on rrpc
lightnvm: fix out of bound ppa lun id on bb tbl
lightnvm: refactor set_bb_tbl for accepting ppa list
lightnvm: move responsibility for bad blk mgmt to target
lightnvm: make nvm_set_rqd_ppalist() aware of vblks
lightnvm: remove struct factory_blks
lightnvm: refactor device ops->get_bb_tbl()
lightnvm: introduce nvm_for_each_lun_ppa() macro
lightnvm: refactor dev->online_target to global nvm_targets
lightnvm: rename nvm_targets to nvm_tgt_type
...
Some code waits for a metadata update by:
1. flagging that it is needed (MD_CHANGE_DEVS or MD_CHANGE_CLEAN)
2. setting MD_CHANGE_PENDING and waking the management thread
3. waiting for MD_CHANGE_PENDING to be cleared
If the first two are done without locking, the code in md_update_sb()
which checks if it needs to repeat might test if an update is needed
before step 1, then clear MD_CHANGE_PENDING after step 2, resulting
in the wait returning early.
So make sure all places that set MD_CHANGE_PENDING are atomicial, and
bit_clear_unless (suggested by Neil) is introduced for the purpose.
Cc: Martin Kepplinger <martink@posteo.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: <linux-kernel@vger.kernel.org>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
