This is a nasty interface and setting the state of a foreign task must
not be done. As of the following commit:
be628be095 ("bcache: Make gc wakeup sane, remove set_task_state()")
... everyone in the kernel calls set_task_state() with current, allowing
the helper to be removed.
However, as the comment indicates, it is still around for those archs
where computing current is more expensive than using a pointer, at least
in theory. An important arch that is affected is arm64, however this has
been addressed now [1] and performance is up to par making no difference
with either calls.
Of all the callers, if any, it's the locking bits that would care most
about this -- ie: we end up passing a tsk pointer to a lot of the lock
slowpath, and setting ->state on that. The following numbers are based
on two tests: a custom ad-hoc microbenchmark that just measures
latencies (for ~65 million calls) between get_task_state() vs
get_current_state().
Secondly for a higher overview, an unlink microbenchmark was used,
which pounds on a single file with open, close,unlink combos with
increasing thread counts (up to 4x ncpus). While the workload is quite
unrealistic, it does contend a lot on the inode mutex or now rwsem.
[1] https://lkml.kernel.org/r/1483468021-8237-1-git-send-email-mark.rutland@arm.com
== 1. x86-64 ==
Avg runtime set_task_state(): 601 msecs
Avg runtime set_current_state(): 552 msecs
vanilla dirty
Hmean unlink1-processes-2 36089.26 ( 0.00%) 38977.33 ( 8.00%)
Hmean unlink1-processes-5 28555.01 ( 0.00%) 29832.55 ( 4.28%)
Hmean unlink1-processes-8 37323.75 ( 0.00%) 44974.57 ( 20.50%)
Hmean unlink1-processes-12 43571.88 ( 0.00%) 44283.01 ( 1.63%)
Hmean unlink1-processes-21 34431.52 ( 0.00%) 38284.45 ( 11.19%)
Hmean unlink1-processes-30 34813.26 ( 0.00%) 37975.17 ( 9.08%)
Hmean unlink1-processes-48 37048.90 ( 0.00%) 39862.78 ( 7.59%)
Hmean unlink1-processes-79 35630.01 ( 0.00%) 36855.30 ( 3.44%)
Hmean unlink1-processes-110 36115.85 ( 0.00%) 39843.91 ( 10.32%)
Hmean unlink1-processes-141 32546.96 ( 0.00%) 35418.52 ( 8.82%)
Hmean unlink1-processes-172 34674.79 ( 0.00%) 36899.21 ( 6.42%)
Hmean unlink1-processes-203 37303.11 ( 0.00%) 36393.04 ( -2.44%)
Hmean unlink1-processes-224 35712.13 ( 0.00%) 36685.96 ( 2.73%)
== 2. ppc64le ==
Avg runtime set_task_state(): 938 msecs
Avg runtime set_current_state: 940 msecs
vanilla dirty
Hmean unlink1-processes-2 19269.19 ( 0.00%) 30704.50 ( 59.35%)
Hmean unlink1-processes-5 20106.15 ( 0.00%) 21804.15 ( 8.45%)
Hmean unlink1-processes-8 17496.97 ( 0.00%) 17243.28 ( -1.45%)
Hmean unlink1-processes-12 14224.15 ( 0.00%) 17240.21 ( 21.20%)
Hmean unlink1-processes-21 14155.66 ( 0.00%) 15681.23 ( 10.78%)
Hmean unlink1-processes-30 14450.70 ( 0.00%) 15995.83 ( 10.69%)
Hmean unlink1-processes-48 16945.57 ( 0.00%) 16370.42 ( -3.39%)
Hmean unlink1-processes-79 15788.39 ( 0.00%) 14639.27 ( -7.28%)
Hmean unlink1-processes-110 14268.48 ( 0.00%) 14377.40 ( 0.76%)
Hmean unlink1-processes-141 14023.65 ( 0.00%) 16271.69 ( 16.03%)
Hmean unlink1-processes-172 13417.62 ( 0.00%) 16067.55 ( 19.75%)
Hmean unlink1-processes-203 15293.08 ( 0.00%) 15440.40 ( 0.96%)
Hmean unlink1-processes-234 13719.32 ( 0.00%) 16190.74 ( 18.01%)
Hmean unlink1-processes-265 16400.97 ( 0.00%) 16115.22 ( -1.74%)
Hmean unlink1-processes-296 14388.60 ( 0.00%) 16216.13 ( 12.70%)
Hmean unlink1-processes-320 15771.85 ( 0.00%) 15905.96 ( 0.85%)
x86-64 (known to be fast for get_current()/this_cpu_read_stable() caching)
and ppc64 (with paca) show similar improvements in the unlink microbenches.
The small delta for ppc64 (2ms), does not represent the gains on the unlink
runs. In the case of x86, there was a decent amount of variation in the
latency runs, but always within a 20 to 50ms increase), ppc was more constant.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@stgolabs.net
Cc: mark.rutland@arm.com
Link: http://lkml.kernel.org/r/1483479794-14013-5-git-send-email-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This fixes a build error on certain architectures, such as ppc64.
Fixes: 6995f0b247e("md: takeover should clear unrelated bits")
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Commit 6995f0b (md: takeover should clear unrelated bits) clear
unrelated bits, but it's quite fragile. To avoid error in the future,
define a macro for unsupported mddev flags for each raid type and use it
to clear unsupported mddev flags. This should be less error-prone.
Suggested-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Trivial fix to spelling mistake "recoverying" to "recovering" in
pr_dbg message.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Shaohua Li <shli@fb.com>
r5l_load_log() calls functions that requires a proper conf->log,
for example, r5c_is_writeback(). Therefore, we should set
conf->log before calling r5l_load_log(). If r5l_load_log() fails,
conf->log is set back to NULL.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
We only need to update sh->log_start at the end of recovery,
which is r5c_recovery_rewrite_data_only_stripes(), so it is not
necessary to set it before that. In this patch, log_start is
removed from r5c_recovery_alloc_stripe().
After updating all sh->log_start, rewrite_data_only_stripes()
also updates log->next_checkpoints to the last sh->log_start.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The write-through mode has been returned in front of the function,
do not need to do it again.
Signed-off-by: JackieLiu <liuyun01@kylinos.cn>
Reviewed-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Refactor raid10_make_request into seperate read and write functions to
clean up the code.
Shaohua: add the recovery check back to read path
Signed-off-by: Robert LeBlanc <robert@leblancnet.us>
Signed-off-by: Shaohua Li <shli@fb.com>
Refactor raid1_make_request to make read and write code in their own
functions to clean up the code.
Signed-off-by: Robert LeBlanc <robert@leblancnet.us>
Signed-off-by: Shaohua Li <shli@fb.com>
This was entirely automated, using the script by Al:
PATT='^[[:blank:]]*#[[:blank:]]*include[[:blank:]]*<asm/uaccess.h>'
sed -i -e "s!$PATT!#include <linux/uaccess.h>!" \
$(git grep -l "$PATT"|grep -v ^include/linux/uaccess.h)
to do the replacement at the end of the merge window.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__bitwise__ used to mean "yes, please enable sparse checks
unconditionally", but now that we dropped __CHECK_ENDIAN__
__bitwise is exactly the same.
There aren't many users, replace it by __bitwise everywhere.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Stefan Schmidt <stefan@osg.samsung.com>
Acked-by: Krzysztof Kozlowski <krzk@kernel.org>
Akced-by: Lee Duncan <lduncan@suse.com>
. some locking improvements in DM bufio
. add Kconfig option to disable the DM block manager's extra locking
which mainly serves as a developer tool
. a few bug fixes to DM's persistent-data
. a couple changes to prepare for multipage biovec support in the block
layer
. various improvements and cleanups in the DM core, DM cache, DM raid
and DM crypt
. add ability to have DM crypt use keys from the kernel key retention
service
. add a new "error_writes" feature to the DM flakey target, reads are
left unchanged in this mode
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Merge tag 'dm-4.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- various fixes and improvements to request-based DM and DM multipath
- some locking improvements in DM bufio
- add Kconfig option to disable the DM block manager's extra locking
which mainly serves as a developer tool
- a few bug fixes to DM's persistent-data
- a couple changes to prepare for multipage biovec support in the block
layer
- various improvements and cleanups in the DM core, DM cache, DM raid
and DM crypt
- add ability to have DM crypt use keys from the kernel key retention
service
- add a new "error_writes" feature to the DM flakey target, reads are
left unchanged in this mode
* tag 'dm-4.10-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (40 commits)
dm flakey: introduce "error_writes" feature
dm cache policy smq: use hash_32() instead of hash_32_generic()
dm crypt: reject key strings containing whitespace chars
dm space map: always set ev if sm_ll_mutate() succeeds
dm space map metadata: skip useless memcpy in metadata_ll_init_index()
dm space map metadata: fix 'struct sm_metadata' leak on failed create
Documentation: dm raid: define data_offset status field
dm raid: fix discard support regression
dm raid: don't allow "write behind" with raid4/5/6
dm mpath: use hw_handler_params if attached hw_handler is same as requested
dm crypt: add ability to use keys from the kernel key retention service
dm array: remove a dead assignment in populate_ablock_with_values()
dm ioctl: use offsetof() instead of open-coding it
dm rq: simplify use_blk_mq initialization
dm: use blk_set_queue_dying() in __dm_destroy()
dm bufio: drop the lock when doing GFP_NOIO allocation
dm bufio: don't take the lock in dm_bufio_shrink_count
dm bufio: avoid sleeping while holding the dm_bufio lock
dm table: simplify dm_table_determine_type()
dm table: an 'all_blk_mq' table must be loaded for a blk-mq DM device
...
Recent dm-flakey fixes, to have reads error out during the "down"
interval, made it so that the previous read behaviour is no longer
available.
It is useful to have reads complete like normal but have writes error
out, so make it possible again with a new "error_writes" feature.
Signed-off-by: Mike Snitzer <snitzer@redhat.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>
When we change level from raid1 to raid5, the MD_FAILFAST_SUPPORTED bit
will be accidentally set, but raid5 doesn't support it. The same is true
for the MD_HAS_JOURNAL bit.
Fix: 46533ff (md: Use REQ_FAILFAST_* on metadata writes where appropriate)
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Unfortunately key_string may theoretically contain whitespace even after
it's processed by dm_split_args(). The reason for this is DM core
supports escaping of almost all chars including any whitespace.
If userspace passes a key to the kernel in format ":32:logon:my_prefix:my\ key"
dm-crypt will look up key "my_prefix:my key" in kernel keyring service.
So far everything's fine.
Unfortunately if userspace later calls DM_TABLE_STATUS ioctl, it will not
receive back expected ":32:logon:my_prefix:my\ key" but the unescaped version
instead. Also userpace (most notably cryptsetup) is not ready to parse
single target argument containing (even escaped) whitespace chars and any
whitespace is simply taken as delimiter of another argument.
This effect is mitigated by the fact libdevmapper curently performs
double escaping of '\' char. Any user input in format "x\ x" is
transformed into "x\\ x" before being passed to the kernel. Nonetheless
dm-crypt may be used without libdevmapper. Therefore the near-term
solution to this is to reject any key string containing whitespace.
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If no block was allocated or freed, sm_ll_mutate() wasn't setting
*ev, leaving the variable unitialized. sm_ll_insert(),
sm_disk_inc_block(), and sm_disk_new_block() all check ev to see
if there was an allocation event in sm_ll_mutate(), possibly
reading unitialized data.
If no allocation event occured, sm_ll_mutate() should set *ev
to SM_NONE.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When metadata_ll_init_index() is called by sm_ll_new_metadata(),
ll->mi_le hasn't been initialized yet. So, when
metadata_ll_init_index() copies the contents of ll->mi_le into the
newly allocated bitmap_root, it is just copying garbage. ll->mi_le
will be allocated later in sm_ll_extend() and copied into the
bitmap_root, in sm_ll_commit().
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
In dm_sm_metadata_create() we temporarily change the dm_space_map
operations from 'ops' (whose .destroy function deallocates the
sm_metadata) to 'bootstrap_ops' (whose .destroy function doesn't).
If dm_sm_metadata_create() fails in sm_ll_new_metadata() or
sm_ll_extend(), it exits back to dm_tm_create_internal(), which calls
dm_sm_destroy() with the intention of freeing the sm_metadata, but it
doesn't (because the dm_space_map operations is still set to
'bootstrap_ops').
Fix this by setting the dm_space_map operations back to 'ops' if
dm_sm_metadata_create() fails when it is set to 'bootstrap_ops'.
Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>
Acked-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
Commit ecbfb9f118 ("dm raid: add raid level takeover support") moved the
configure_discard_support() call from raid_ctr() to raid_preresume().
Enabling/disabling discard _must_ happen during table load (through the
.ctr hook). Fix this regression by moving the
configure_discard_support() call back to raid_ctr().
Fixes: ecbfb9f118 ("dm raid: add raid level takeover support")
Cc: stable@vger.kernel.org # 4.8+
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Remove CTR_FLAG_MAX_WRITE_BEHIND from raid4/5/6's valid ctr flags.
Only the md raid1 personality supports setting a maximum number
of "write behind" write IOs on any legs set to "write mostly".
"write mostly" enhances throughput with slow links/disks.
Technically the "write behind" value is a write intent bitmap
property only being respected by the raid1 personality. It allows a
maximum number of "write behind" writes to any "write mostly" raid1
mirror legs to be delayed and avoids reads from such legs.
No other MD personalities supported via dm-raid make use of "write
behind", thus setting this property is superfluous; it wouldn't cause
harm but it is correct to reject it.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Let the requested m->hw_handler_params be used if the attached hardware
handler is the same handler as requested with m->hw_handler_name.
Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The kernel key service is a generic way to store keys for the use of
other subsystems. Currently there is no way to use kernel keys in dm-crypt.
This patch aims to fix that. Instead of key userspace may pass a key
description with preceding ':'. So message that constructs encryption
mapping now looks like this:
<cipher> [<key>|:<key_string>] <iv_offset> <dev_path> <start> [<#opt_params> <opt_params>]
where <key_string> is in format: <key_size>:<key_type>:<key_description>
Currently we only support two elementary key types: 'user' and 'logon'.
Keys may be loaded in dm-crypt either via <key_string> or using
classical method and pass the key in hex representation directly.
dm-crypt device initialised with a key passed in hex representation may be
replaced with key passed in key_string format and vice versa.
(Based on original work by Andrey Ryabinin)
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
A value is assigned to 'nr_entries' but is never used, remove it.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Subtracting sizes is a fragile approach because the result is only
correct if the compiler has not added any padding at the end of the
structure. Hence use offsetof() instead of size subtraction. An
additional advantage of offsetof() is that it makes the intent more
clear.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Use a single statement to declare and initialize 'use_blk_mq' instead
of two statements.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
After QUEUE_FLAG_DYING has been set any code that is waiting in
get_request() should be woken up. But to get this behaviour
blk_set_queue_dying() must be used instead of only setting
QUEUE_FLAG_DYING.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If the first allocation attempt using GFP_NOWAIT fails, drop the lock
and retry using GFP_NOIO allocation (lock is dropped because the
allocation can take some time).
Note that we won't do GFP_NOIO allocation when we loop for the second
time, because the lock shouldn't be dropped between __wait_for_free_buffer
and __get_unclaimed_buffer.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm_bufio_shrink_count() is called from do_shrink_slab to find out how many
freeable objects are there. The reported value doesn't have to be precise,
so we don't need to take the dm-bufio lock.
Suggested-by: David Rientjes <rientjes@google.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
We've seen in-field reports showing _lots_ (18 in one case, 41 in
another) of tasks all sitting there blocked on:
mutex_lock+0x4c/0x68
dm_bufio_shrink_count+0x38/0x78
shrink_slab.part.54.constprop.65+0x100/0x464
shrink_zone+0xa8/0x198
In the two cases analyzed, we see one task that looks like this:
Workqueue: kverityd verity_prefetch_io
__switch_to+0x9c/0xa8
__schedule+0x440/0x6d8
schedule+0x94/0xb4
schedule_timeout+0x204/0x27c
schedule_timeout_uninterruptible+0x44/0x50
wait_iff_congested+0x9c/0x1f0
shrink_inactive_list+0x3a0/0x4cc
shrink_lruvec+0x418/0x5cc
shrink_zone+0x88/0x198
try_to_free_pages+0x51c/0x588
__alloc_pages_nodemask+0x648/0xa88
__get_free_pages+0x34/0x7c
alloc_buffer+0xa4/0x144
__bufio_new+0x84/0x278
dm_bufio_prefetch+0x9c/0x154
verity_prefetch_io+0xe8/0x10c
process_one_work+0x240/0x424
worker_thread+0x2fc/0x424
kthread+0x10c/0x114
...and that looks to be the one holding the mutex.
The problem has been reproduced on fairly easily:
0. Be running Chrome OS w/ verity enabled on the root filesystem
1. Pick test patch: http://crosreview.com/412360
2. Install launchBalloons.sh and balloon.arm from
http://crbug.com/468342
...that's just a memory stress test app.
3. On a 4GB rk3399 machine, run
nice ./launchBalloons.sh 4 900 100000
...that tries to eat 4 * 900 MB of memory and keep accessing.
4. Login to the Chrome web browser and restore many tabs
With that, I've seen printouts like:
DOUG: long bufio 90758 ms
...and stack trace always show's we're in dm_bufio_prefetch().
The problem is that we try to allocate memory with GFP_NOIO while
we're holding the dm_bufio lock. Instead we should be using
GFP_NOWAIT. Using GFP_NOIO can cause us to sleep while holding the
lock and that causes the above problems.
The current behavior explained by David Rientjes:
It will still try reclaim initially because __GFP_WAIT (or
__GFP_KSWAPD_RECLAIM) is set by GFP_NOIO. This is the cause of
contention on dm_bufio_lock() that the thread holds. You want to
pass GFP_NOWAIT instead of GFP_NOIO to alloc_buffer() when holding a
mutex that can be contended by a concurrent slab shrinker (if
count_objects didn't use a trylock, this pattern would trivially
deadlock).
This change significantly increases responsiveness of the system while
in this state. It makes a real difference because it unblocks kswapd.
In the bug report analyzed, kswapd was hung:
kswapd0 D ffffffc000204fd8 0 72 2 0x00000000
Call trace:
[<ffffffc000204fd8>] __switch_to+0x9c/0xa8
[<ffffffc00090b794>] __schedule+0x440/0x6d8
[<ffffffc00090bac0>] schedule+0x94/0xb4
[<ffffffc00090be44>] schedule_preempt_disabled+0x28/0x44
[<ffffffc00090d900>] __mutex_lock_slowpath+0x120/0x1ac
[<ffffffc00090d9d8>] mutex_lock+0x4c/0x68
[<ffffffc000708e7c>] dm_bufio_shrink_count+0x38/0x78
[<ffffffc00030b268>] shrink_slab.part.54.constprop.65+0x100/0x464
[<ffffffc00030dbd8>] shrink_zone+0xa8/0x198
[<ffffffc00030e578>] balance_pgdat+0x328/0x508
[<ffffffc00030eb7c>] kswapd+0x424/0x51c
[<ffffffc00023f06c>] kthread+0x10c/0x114
[<ffffffc000203dd0>] ret_from_fork+0x10/0x40
By unblocking kswapd memory pressure should be reduced.
Suggested-by: David Rientjes <rientjes@google.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Use a single loop instead of two loops to determine whether or not
all_blk_mq has to be set.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When dm_table_set_type() is used by a target to establish a DM table's
type (e.g. DM_TYPE_MQ_REQUEST_BASED in the case of DM multipath) the
DM core must go on to verify that the devices in the table are
compatible with the established type.
Fixes: e83068a5 ("dm mpath: add optional "queue_mode" feature")
Cc: stable@vger.kernel.org # 4.8+
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
An earlier DM multipath table could have been build ontop of underlying
devices that were all using blk-mq. In that case, if that active
multipath table is replaced with an empty DM multipath table (that
reflects all paths have failed) then it is important that the
'all_blk_mq' state of the active table is transfered to the new empty DM
table. Otherwise dm-rq.c:dm_old_prep_tio() will incorrectly clone a
request that isn't needed by the DM multipath target when it is to issue
IO to an underlying blk-mq device.
Fixes: e83068a5 ("dm mpath: add optional "queue_mode" feature")
Cc: stable@vger.kernel.org # 4.8+
Reported-by: Bart Van Assche <bart.vanassche@sandisk.com>
Tested-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Currently, we increase journal entry seq by 10 after recovery.
However, this is not sufficient in the following case.
After crash the journal looks like
| seq+0 | +1 | +2 | +3 | +4 | +5 | +6 | +7 | ... | +11 | +12 |
If +1 is not valid, we dropped all entries from +1 to +12; and
write seq+10:
| seq+0 | +10 | +2 | +3 | +4 | +5 | +6 | +7 | ... | +11 | +12 |
However, if we write a big journal entry with seq+11, it will
connect with some stale journal entry:
| seq+0 | +10 | +11 | +12 |
To reduce the risk of this issue, we increase seq by 10000 instead.
Shaohua: use 10000 instead of 1000. The risk should be very unlikely. The total
stripe cache size is less than 2k typically, and several stripes can fit into
one meta data block. So the total inflight meta data blocks would be quite
small, which means the the total sequence number used should be quite small.
The 10000 sequence number increase should be far more than safe.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
r5l_recovery_create_empty_meta_block() creates crc for the empty
metablock. After the metablock is updated, we need clear the
checksum before recalculate it.
Shaohua: moved checksum calculation out of
r5l_recovery_create_empty_meta_block. We should calculate it after all fields
are updated.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When create the super-block information, We do not need to do this
recovery stage, only need to initialize some variables.
Signed-off-by: JackieLiu <liuyun01@kylinos.cn>
Reviewed-by: Song Liu <songliubraving@fb.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>
We should update log state after we did a log recovery, current completion
may get wrong log state since log->log_start wasn't initalized until we
called r5l_recovery_log.
At log recovery stage, no lock needed as there is no race conditon.
next_checkpoint field will be initialized in r5l_recovery_log too.
Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Shaohua Li <shli@fb.com>
When recovery is complete, we write an empty block and record his
position first, then make the data-only stripes rewritten done,
the location of the empty block as the last checkpoint position
to write into the super block. And we should update last_checkpoint
to this empty block position.
------------------------------------------------------------------
| old log | empty block | data only stripes | invalid log |
------------------------------------------------------------------
^ ^ ^
| |- log->last_checkpoint |- log->log_start
| |- log->last_cp_seq |- log->next_checkpoint
|- log->seq=n |- log->seq=10+n
At the same time, if there is no data-only stripes, this scene may appear,
| meta1 | meta2 | meta3 |
meta 1 is valid, meta 2 is invalid. meta 3 could be valid. so we should
The solution is we create a new meta in meta2 with its seq == meta1's
seq + 10 and let superblock points to meta2.
Signed-off-by: JackieLiu <liuyun01@kylinos.cn>
Reviewed-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Reviewed-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
With writeback cache, we define log space critical as
free_space < 2 * reclaim_required_space
So the deassert of R5C_LOG_CRITICAL could happen when
1. free_space increases
2. reclaim_required_space decreases
Currently, run_no_space_stripes() is called when 1 happens, but
not (always) when 2 happens.
With this patch, run_no_space_stripes() is call when
R5C_LOG_CRITICAL is cleared.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Current implementation employ 16bit counter of active stripes in lower
bits of bio->bi_phys_segments. If request is big enough to overflow
this counter bio will be completed and freed too early.
Fortunately this not happens in default configuration because several
other limits prevent that: stripe_cache_size * nr_disks effectively
limits count of active stripes. And small max_sectors_kb at lower
disks prevent that during normal read/write operations.
Overflow easily happens in discard if it's enabled by module parameter
"devices_handle_discard_safely" and stripe_cache_size is set big enough.
This patch limits requests size with 256Mb - 8Kb to prevent overflows.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Shaohua Li <shli@kernel.org>
Cc: Neil Brown <neilb@suse.com>
Cc: stable@vger.kernel.org
Signed-off-by: Shaohua Li <shli@fb.com>
R5c_make_stripe_write_out has set this flag, do not need to set again.
Signed-off-by: JackieLiu <liuyun01@kylinos.cn>
Signed-off-by: Shaohua Li <shli@fb.com>
If we released the 'stripe_head' in r5c_recovery_flush_log,
ctx->cached_list will both release the data-parity stripes and
data-only stripes, which will become empty.
And we also need to use the data-only stripes in
r5c_recovery_rewrite_data_only_stripes, so we should wait util rewrite
data-only stripes is done before releasing them.
Reviewed-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Reviewed-by: Song Liu <songliubraving@fb.com>
Signed-off-by: JackieLiu <liuyun01@kylinos.cn>
Signed-off-by: Shaohua Li <shli@fb.com>
'write_pos' must be protected with 'r5l_ring_add', or it may overflow
Signed-off-by: JackieLiu <liuyun01@kylinos.cn>
Reviewed-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The function parameter 'recovery_list' is not used in
body, we can delete it
Signed-off-by: JackieLiu <liuyun01@kylinos.cn>
Reviewed-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
r5c_recovery_load_one_stripe should not set STRIPE_R5C_PARTIAL_STRIPE flag,as
the data-only stripe may be STRIPE_R5C_FULL_STRIPE stripe. The state machine
would release the stripe later and add it into neither r5c_cached_full_stripes
list or r5c_cached_partial_stripes list and set correct flag.
Reviewed-by: JackieLiu <liuyun01@kylinos.cn>
Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Shaohua Li <shli@fb.com>
New stripe that was just allocated has no STRIPE_R5C_CACHING state too,
add this check condition could avoid unnecessary replaying for empty stripe.
r5l_recovery_replay_one_stripe would reset stripe for any case, delete it
to make code more clean.
Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Shaohua Li <shli@fb.com>
We need to re-enable the IRQs here before returning.
Fixes: a39f7afde3 ("md/r5cache: write-out phase and reclaim support")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Shaohua Li <shli@fb.com>
RMW of r5c write back cache uses an extra page to store old data for
prexor. handle_stripe_dirtying() allocates this page by calling
alloc_page(). However, alloc_page() may fail.
To handle alloc_page() failures, this patch adds an extra page to
disk_info. When alloc_page fails, handle_stripe() trys to use these
pages. When these pages are used by other stripe (R5C_EXTRA_PAGE_IN_USE),
the stripe is added to delayed_list.
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: NeilBrown <neilb@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>
When writing to a fastfail device, we use MD_FASTFAIL unless
it is the only device being written to. For
resync/recovery, assume there was a working device to read
from so always use MD_FASTFAIL.
If a write for resync/recovery fails, we just fail the
device - there is not much else to do.
If a normal write fails, but the device cannot be marked
Faulty (must be only one left), we queue for write error
handling which calls narrow_write_error() to write the block
synchronously without any failfast flags.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
If a device is marked FailFast, and it is not the only
device we can read from, we mark the bio as MD_FAILFAST.
If this does fail-fast, we don't try read repair but just
allow failure.
If it was the last device, it doesn't get marked Faulty so
the retry happens on the same device - this time without
FAILFAST. A subsequent failure will not retry but will just
pass up the error.
During resync we may use FAILFAST requests, and on a failure
we will simply use the other device(s).
During recovery we will only use FAILFAST in the unusual
case were there are multiple places to read from - i.e. if
there are > 2 devices. If we get a failure we will fail the
device and complete the resync/recovery with remaining
devices.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When writing to a fastfail device we use MD_FASTFAIL unless
it is the only device being written to.
For resync/recovery, assume there was a working device to
read from so always use REQ_FASTFAIL_DEV.
If a write for resync/recovery fails, we just fail the
device - there is not much else to do.
If a normal failfast write fails, but the device cannot be
failed (must be only one left), we queue for write error
handling. This will call narrow_write_error() to retry the
write synchronously and without any FAILFAST flags.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
If a device is marked FailFast and it is not the only device
we can read from, we mark the bio with REQ_FAILFAST_* flags.
If this does fail, we don't try read repair but just allow
failure. If it was the last device it doesn't fail of
course, so the retry happens on the same device - this time
without FAILFAST. A subsequent failure will not retry but
will just pass up the error.
During resync we may use FAILFAST requests and on a failure
we will simply use the other device(s).
During recovery we will only use FAILFAST in the unusual
case were there are multiple places to read from - i.e. if
there are > 2 devices. If we get a failure we will fail the
device and complete the resync/recovery with remaining
devices.
The new R1BIO_FailFast flag is set on read reqest to suggest
the a FAILFAST request might be acceptable. The rdev needs
to have FailFast set as well for the read to actually use
REQ_FAILFAST_*.
We need to know there are at least two working devices
before we can set R1BIO_FailFast, so we mustn't stop looking
at the first device we find. So the "min_pending == 0"
handling to not exit early, but too always choose the
best_pending_disk if min_pending == 0.
The spinlocked region in raid1_error() in enlarged to ensure
that if two bios, reading from two different devices, fail
at the same time, then there is no risk that both devices
will be marked faulty, leaving zero "In_sync" devices.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@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>
Instead we use standard iterator way to do that.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Some drivers often use external bvec table, so introduce
this helper for this case. It is always safe to access the
bio->bi_io_vec in this way for this case.
After converting to this usage, it will becomes a bit easier
to evaluate the remaining direct access to bio->bi_io_vec,
so it can help to prepare for the following multipage bvec
support.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Fixed up the new O_DIRECT cases.
Signed-off-by: Jens Axboe <axboe@fb.com>
Purely cleanup, avoids potential for strange coding bugs. But in
reality if __multipath_map() fails the caller has no business looking at
*__clone.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
None of the callers of pg_init_all_paths() check its return value.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This avoids the potential for invalid memory access, if/when there are
no priority groups, in response to invalid arguments being sent by the
user via DM message (e.g. "switch_group", "disable_group" or
"enable_group").
Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Avoids false positive of no hardware handler being specified (which is
implied by a NULL m->hw_handler_name).
Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Fix to return error code -EINVAL instead of 0, as is done elsewhere in
this function.
Fixes: e80d1c805a ("dm: do not override error code returned from dm_get_device()")
Cc: stable@vger.kernel.org # 4.3+
Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The crypt_iv_operations are never modified, so declare them
as const.
Done with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When target 1.9.1 gets takeover/reshape requests on devices with old superblock
format not supporting such conversions and rejects them in super_init_validation(),
it logs bogus error message (e.g. Reshape when a takeover is requested).
Whilst on it, add messages for disk adding/removing and stripe sectors
reshape requests, use the newer rs_{takeover,reshape}_requested() API,
address a raid10 false positive in checking array positions and
remove rs_set_new() because device members are already set proper.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
In the past, dm-crypt used per-cpu crypto context. This has been removed
in the kernel 3.15 and the crypto context is shared between all cpus. This
patch renames the function crypt_setkey_allcpus to crypt_setkey, because
there is really no activity that is done for all cpus.
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
In crypt_set_key(), if a failure occurs while replacing the old key
(e.g. tfm->setkey() fails) the key must not have DM_CRYPT_KEY_VALID flag
set. Otherwise, the crypto layer would have an invalid key that still
has DM_CRYPT_KEY_VALID flag set.
Cc: stable@vger.kernel.org
Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Use bio_add_page(), the standard interface for adding a page to a bio,
rather than open-coding the same.
It should be noted that the 'clone' bio that is allocated using
bio_alloc_bioset(), in crypt_alloc_buffer(), does _not_ set the
bio's BIO_CLONED flag. As such, bio_add_page()'s early return for true
bio clones (those with BIO_CLONED set) isn't applicable.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Firstly we have mature bvec/bio iterator helper for iterate each
page in one bio, not necessary to reinvent a wheel to do that.
Secondly the coming multipage bvecs requires this patch.
Also add comments about the direct access to bvec table.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Avoid accessing .bi_vcnt directly, because the bio can be split from
block layer and .bi_vcnt should never have been used here.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
With raid5 cache, we committing data from journal device. When
there is flush request, we need to flush journal device's cache.
This was not needed in raid5 journal, because we will flush the
journal before committing data to raid disks.
This is similar to FUA, except that we also need flush journal for
FUA. Otherwise, corruptions in earlier meta data will stop recovery
from reaching FUA data.
slightly changed the code by Shaohua
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
1. In previous patch, we:
- add new data to r5l_recovery_ctx
- add new functions to recovery write-back cache
The new functions are not used in this patch, so this patch does not
change the behavior of recovery.
2. In this patchpatch, we:
- modify main recovery procedure r5l_recovery_log() to call new
functions
- remove old functions
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Recovery of write-back cache has different logic to write-through only
cache. Specifically, for write-back cache, the recovery need to scan
through all active journal entries before flushing data out. Therefore,
large portion of the recovery logic is rewritten here.
To make the diffs cleaner, we split the rewrite as follows:
1. In this patch, we:
- add new data to r5l_recovery_ctx
- add new functions to recovery write-back cache
The new functions are not used in this patch, so this patch does not
change the behavior of recovery.
2. In next patch, we:
- modify main recovery procedure r5l_recovery_log() to call new
functions
- remove old functions
With cache feature, there are 2 different scenarios of recovery:
1. Data-Parity stripe: a stripe with complete parity in journal.
2. Data-Only stripe: a stripe with only data in journal (or partial
parity).
The code differentiate Data-Parity stripe from Data-Only stripe with
flag STRIPE_R5C_CACHING.
For Data-Parity stripes, we use the same procedure as raid5 journal,
where all the data and parity are replayed to the RAID devices.
For Data-Only strips, we need to finish complete calculate parity and
finish the full reconstruct write or RMW write. For simplicity, in
the recovery, we load the stripe to stripe cache. Once the array is
started, the stripe cache state machine will handle these stripes
through normal write path.
r5c_recovery_flush_log contains the main procedure of recovery. The
recovery code first scans through the journal and loads data to
stripe cache. The code keeps tracks of all these stripes in a list
(use sh->lru and ctx->cached_list), stripes in the list are
organized in the order of its first appearance on the journal.
During the scan, the recovery code assesses each stripe as
Data-Parity or Data-Only.
During scan, the array may run out of stripe cache. In these cases,
the recovery code will also call raid5_set_cache_size to increase
stripe cache size. If the array still runs out of stripe cache
because there isn't enough memory, the array will not assemble.
At the end of scan, the recovery code replays all Data-Parity
stripes, and sets proper states for Data-Only stripes. The recovery
code also increases seq number by 10 and rewrites all Data-Only
stripes to journal. This is to avoid confusion after repeated
crashes. More details is explained in raid5-cache.c before
r5c_recovery_rewrite_data_only_stripes().
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
1. rename r5l_read_meta_block() as r5l_recovery_read_meta_block();
2. pull the code that initialize r5l_meta_block from
r5l_log_write_empty_meta_block() to a separate function
r5l_recovery_create_empty_meta_block(), so that we can reuse this
piece of code.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
With write cache, journal_mode is the knob to switch between
write-back and write-through.
Below is an example:
root@virt-test:~/# cat /sys/block/md0/md/journal_mode
[write-through] write-back
root@virt-test:~/# echo write-back > /sys/block/md0/md/journal_mode
root@virt-test:~/# cat /sys/block/md0/md/journal_mode
write-through [write-back]
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
There are two limited resources, stripe cache and journal disk space.
For better performance, we priotize reclaim of full stripe writes.
To free up more journal space, we free earliest data on the journal.
In current implementation, reclaim happens when:
1. Periodically (every R5C_RECLAIM_WAKEUP_INTERVAL, 30 seconds) reclaim
if there is no reclaim in the past 5 seconds.
2. when there are R5C_FULL_STRIPE_FLUSH_BATCH (256) cached full stripes,
or cached stripes is enough for a full stripe (chunk size / 4k)
(r5c_check_cached_full_stripe)
3. when there is pressure on stripe cache (r5c_check_stripe_cache_usage)
4. when there is pressure on journal space (r5l_write_stripe, r5c_cache_data)
r5c_do_reclaim() contains new logic of reclaim.
For stripe cache:
When stripe cache pressure is high (more than 3/4 stripes are cached,
or there is empty inactive lists), flush all full stripe. If fewer
than R5C_RECLAIM_STRIPE_GROUP (NR_STRIPE_HASH_LOCKS * 2) full stripes
are flushed, flush some paritial stripes. When stripe cache pressure
is moderate (1/2 to 3/4 of stripes are cached), flush all full stripes.
For log space:
To avoid deadlock due to log space, we need to reserve enough space
to flush cached data. The size of required log space depends on total
number of cached stripes (stripe_in_journal_count). In current
implementation, the writing-out phase automatically include pending
data writes with parity writes (similar to write through case).
Therefore, we need up to (conf->raid_disks + 1) pages for each cached
stripe (1 page for meta data, raid_disks pages for all data and
parity). r5c_log_required_to_flush_cache() calculates log space
required to flush cache. In the following, we refer to the space
calculated by r5c_log_required_to_flush_cache() as
reclaim_required_space.
Two flags are added to r5conf->cache_state: R5C_LOG_TIGHT and
R5C_LOG_CRITICAL. R5C_LOG_TIGHT is set when free space on the log
device is less than 3x of reclaim_required_space. R5C_LOG_CRITICAL
is set when free space on the log device is less than 2x of
reclaim_required_space.
r5c_cache keeps all data in cache (not fully committed to RAID) in
a list (stripe_in_journal_list). These stripes are in the order of their
first appearance on the journal. So the log tail (last_checkpoint)
should point to the journal_start of the first item in the list.
When R5C_LOG_TIGHT is set, r5l_reclaim_thread starts flushing out
stripes at the head of stripe_in_journal. When R5C_LOG_CRITICAL is
set, the state machine only writes data that are already in the
log device (in stripe_in_journal_list).
This patch includes a fix to improve performance by
Shaohua Li <shli@fb.com>.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
As described in previous patch, write back cache operates in two
phases: caching and writing-out. The caching phase works as:
1. write data to journal
(r5c_handle_stripe_dirtying, r5c_cache_data)
2. call bio_endio
(r5c_handle_data_cached, r5c_return_dev_pending_writes).
Then the writing-out phase is as:
1. Mark the stripe as write-out (r5c_make_stripe_write_out)
2. Calcualte parity (reconstruct or RMW)
3. Write parity (and maybe some other data) to journal device
4. Write data and parity to RAID disks
This patch implements caching phase. The cache is integrated with
stripe cache of raid456. It leverages code of r5l_log to write
data to journal device.
Writing-out phase of the cache is implemented in the next patch.
With r5cache, write operation does not wait for parity calculation
and write out, so the write latency is lower (1 write to journal
device vs. read and then write to raid disks). Also, r5cache will
reduce RAID overhead (multipile IO due to read-modify-write of
parity) and provide more opportunities of full stripe writes.
This patch adds 2 flags to stripe_head.state:
- STRIPE_R5C_PARTIAL_STRIPE,
- STRIPE_R5C_FULL_STRIPE,
Instead of inactive_list, stripes with cached data are tracked in
r5conf->r5c_full_stripe_list and r5conf->r5c_partial_stripe_list.
STRIPE_R5C_FULL_STRIPE and STRIPE_R5C_PARTIAL_STRIPE are flags for
stripes in these lists. Note: stripes in r5c_full/partial_stripe_list
are not considered as "active".
For RMW, the code allocates an extra page for each data block
being updated. This is stored in r5dev->orig_page and the old data
is read into it. Then the prexor calculation subtracts ->orig_page
from the parity block, and the reconstruct calculation adds the
->page data back into the parity block.
r5cache naturally excludes SkipCopy. When the array has write back
cache, async_copy_data() will not skip copy.
There are some known limitations of the cache implementation:
1. Write cache only covers full page writes (R5_OVERWRITE). Writes
of smaller granularity are write through.
2. Only one log io (sh->log_io) for each stripe at anytime. Later
writes for the same stripe have to wait. This can be improved by
moving log_io to r5dev.
3. With writeback cache, read path must enter state machine, which
is a significant bottleneck for some workloads.
4. There is no per stripe checkpoint (with r5l_payload_flush) in
the log, so recovery code has to replay more than necessary data
(sometimes all the log from last_checkpoint). This reduces
availability of the array.
This patch includes a fix proposed by ZhengYuan Liu
<liuzhengyuan@kylinos.cn>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
This patch adds state machine for raid5-cache. With log device, the
raid456 array could operate in two different modes (r5c_journal_mode):
- write-back (R5C_MODE_WRITE_BACK)
- write-through (R5C_MODE_WRITE_THROUGH)
Existing code of raid5-cache only has write-through mode. For write-back
cache, it is necessary to extend the state machine.
With write-back cache, every stripe could operate in two different
phases:
- caching
- writing-out
In caching phase, the stripe handles writes as:
- write to journal
- return IO
In writing-out phase, the stripe behaviors as a stripe in write through
mode R5C_MODE_WRITE_THROUGH.
STRIPE_R5C_CACHING is added to sh->state to differentiate caching and
writing-out phase.
Please note: this is a "no-op" patch for raid5-cache write-through
mode.
The following detailed explanation is copied from the raid5-cache.c:
/*
* raid5 cache state machine
*
* With rhe RAID cache, each stripe works in two phases:
* - caching phase
* - writing-out phase
*
* These two phases are controlled by bit STRIPE_R5C_CACHING:
* if STRIPE_R5C_CACHING == 0, the stripe is in writing-out phase
* if STRIPE_R5C_CACHING == 1, the stripe is in caching phase
*
* When there is no journal, or the journal is in write-through mode,
* the stripe is always in writing-out phase.
*
* For write-back journal, the stripe is sent to caching phase on write
* (r5c_handle_stripe_dirtying). r5c_make_stripe_write_out() kicks off
* the write-out phase by clearing STRIPE_R5C_CACHING.
*
* Stripes in caching phase do not write the raid disks. Instead, all
* writes are committed from the log device. Therefore, a stripe in
* caching phase handles writes as:
* - write to log device
* - return IO
*
* Stripes in writing-out phase handle writes as:
* - calculate parity
* - write pending data and parity to journal
* - write data and parity to raid disks
* - return IO for pending writes
*/
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Move some define and inline functions to raid5.h, so they can be
used in raid5-cache.c
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Currently, r5l_write_stripe checks meta size for each stripe write,
which is not necessary.
With this patch, r5l_init_log checks maximal meta size of the array,
which is (r5l_meta_block + raid_disks x r5l_payload_data_parity).
If this is too big to fit in one page, r5l_init_log aborts.
With current meta data, r5l_log support raid_disks up to 203.
Signed-off-by: Song Liu <songliubraving@fb.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>
Both raid1 and raid10 will sometimes delay handling an IO request,
such as when resync is happening or there are too many requests queued.
Add some blktrace messsages so we can see when that is happening when
looking for performance artefacts.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
We trace wheneven bitmap_unplug() finds that it needs to write
to the bitmap, or when bitmap_daemon_work() find there is work
to do.
This makes it easier to correlate bitmap updates with data writes.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
The block tracing infrastructure (accessed with blktrace/blkparse)
supports the tracing of mapping bios from one device to another.
This is currently used when a bio in a partition is mapped to the
whole device, when bios are mapped by dm, and for mapping in md/raid5.
Other md personalities do not include this tracing yet, so add it.
When a read-error is detected we redirect the request to a different device.
This could justifiably be seen as a new mapping for the originial bio,
or a secondary mapping for the bio that errors. This patch uses
the second option.
When md is used under dm-raid, the mappings are not traced as we do
not have access to the block device number of the parent.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
It is required to hold the queue lock when calling blk_run_queue_async()
to avoid that a race between blk_run_queue_async() and
blk_cleanup_queue() is triggered.
Cc: stable@vger.kernel.org
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
The block manager's locking is useful for catching cycles that may
result from certain btree metadata corruption. But in general it serves
as a developer tool to catch bugs in code. Unless you're finding that
DM thin provisioning is hanging due to infinite loops within the block
manager's access to btree nodes you can safely disable this feature.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de> # do/while(0) macro fix
Signed-off-by: Mike Snitzer <snitzer@redhat.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>
While performing a resync/recovery, raid1 divides the
array space into three regions:
- before the resync
- at or shortly after the resync point
- much further ahead of the resync point.
Write requests to the first or third do not need to wait. Write
requests to the middle region do need to wait if resync requests are
pending.
If there are any active write requests in the middle region, resync
will wait for them.
Due to an accounting error, there is a small range of addresses,
between conf->next_resync and conf->start_next_window, where write
requests will *not* be blocked, but *will* be counted in the middle
region. This can effectively block resync indefinitely if filesystem
writes happen repeatedly to this region.
As ->next_window_requests is incremented when the sector is after
conf->start_next_window + NEXT_NORMALIO_DISTANCE
the same boundary should be used for determining when write requests
should wait.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
As we don't wait for writes to complete in bitmap_daemon_work, they
could still be in-flight when bitmap_unplug writes again. Or when
bitmap_daemon_work tries to write again.
This can be confusing and could risk the wrong data being written last.
So make sure we wait for old writes to complete before new writes start.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When writing to an array with a bitmap enabled, the writes are grouped
in batches which are preceded by an update to the bitmap.
It is quite likely if that a drive develops a problem which is not
media related, that the bitmap write will be the first to report an
error and cause the device to be marked faulty (as the bitmap write is
at the start of a batch).
In this case, there is point submiting the subsequent writes to the
failed device - that just wastes times.
So re-check the Faulty state of a device before submitting a
delayed write.
This requires that we keep the 'rdev', rather than the 'bdev' in the
bio, then swap in the bdev just before final submission.
Reported-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
When writing to an array with a bitmap enabled, the writes are grouped
in batches which are preceded by an update to the bitmap.
It is quite likely if that a drive develops a problem which is not
media related, that the bitmap write will be the first to report an
error and cause the device to be marked faulty (as the bitmap write is
at the start of a batch).
In this case, there is point submiting the subsequent writes to the
failed device - that just wastes times.
So re-check the Faulty state of a device before submitting a
delayed write.
This requires that we keep the 'rdev', rather than the 'bdev' in the
bio, then swap in the bdev just before final submission.
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>
We can calculate this offset by using ctx->meta_total_blocks,
without passing in from the function
Signed-off-by: JackieLiu <liuyun01@kylinos.cn>
Signed-off-by: Shaohua Li <shli@fb.com>
This makes md/raid0 much less verbose as the messages about
the array geometry are now pr_debug()
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Also remove all messages about memory allocation failure.
page_alloc() reports those.
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Follow err/warn distinction introduced in md.c
Join multi-part strings into single string.
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>
It is possible that bitmap_storage_alloc could return -ENOMEM,
and some member inside store could be allocated such as filemap.
To avoid memory leak, we need to call bitmap_file_unmap to free
those members in the bitmap_resize.
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Revert commit 11367799f3 ("md: Prevent IO hold during accessing to faulty
raid5 array") as it doesn't comply with commit c3cce6cda1 ("md/raid5:
ensure device failure recorded before write request returns."). That change
is not required anymore as the problem is resolved by commit 16f889499a
("md: report 'write_pending' state when array in sync") - read request is
stuck as array state is not reported correctly via sysfs attribute.
Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.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>
Pull MD fixes from Shaohua Li:
"There are several bug fixes queued:
- fix raid5-cache recovery bugs
- fix discard IO error handling for raid1/10
- fix array sync writes bogus position to superblock
- fix IO error handling for raid array with external metadata"
* tag 'md/4.9-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/shli/md:
md: be careful not lot leak internal curr_resync value into metadata. -- (all)
raid1: handle read error also in readonly mode
raid5-cache: correct condition for empty metadata write
md: report 'write_pending' state when array in sync
md/raid5: write an empty meta-block when creating log super-block
md/raid5: initialize next_checkpoint field before use
RAID10: ignore discard error
RAID1: ignore discard error
Ensure that all ongoing dm_mq_queue_rq() and dm_mq_requeue_request()
calls have stopped before setting the "queue stopped" flag. This
allows to remove the "queue stopped" test from dm_mq_queue_rq() and
dm_mq_requeue_request(). This patch fixes a race condition because
dm_mq_queue_rq() is called without holding the queue lock and hence
BLK_MQ_S_STOPPED can be set at any time while dm_mq_queue_rq() is
in progress. This patch prevents that the following hang occurs
sporadically when using dm-mq:
INFO: task systemd-udevd:10111 blocked for more than 480 seconds.
Call Trace:
[<ffffffff8161f397>] schedule+0x37/0x90
[<ffffffff816239ef>] schedule_timeout+0x27f/0x470
[<ffffffff8161e76f>] io_schedule_timeout+0x9f/0x110
[<ffffffff8161fb36>] bit_wait_io+0x16/0x60
[<ffffffff8161f929>] __wait_on_bit_lock+0x49/0xa0
[<ffffffff8114fe69>] __lock_page+0xb9/0xc0
[<ffffffff81165d90>] truncate_inode_pages_range+0x3e0/0x760
[<ffffffff81166120>] truncate_inode_pages+0x10/0x20
[<ffffffff81212a20>] kill_bdev+0x30/0x40
[<ffffffff81213d41>] __blkdev_put+0x71/0x360
[<ffffffff81214079>] blkdev_put+0x49/0x170
[<ffffffff812141c0>] blkdev_close+0x20/0x30
[<ffffffff811d48e8>] __fput+0xe8/0x1f0
[<ffffffff811d4a29>] ____fput+0x9/0x10
[<ffffffff810842d3>] task_work_run+0x83/0xb0
[<ffffffff8106606e>] do_exit+0x3ee/0xc40
[<ffffffff8106694b>] do_group_exit+0x4b/0xc0
[<ffffffff81073d9a>] get_signal+0x2ca/0x940
[<ffffffff8101bf43>] do_signal+0x23/0x660
[<ffffffff810022b3>] exit_to_usermode_loop+0x73/0xb0
[<ffffffff81002cb0>] syscall_return_slowpath+0xb0/0xc0
[<ffffffff81624e33>] entry_SYSCALL_64_fastpath+0xa6/0xa8
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Instead of manipulating both QUEUE_FLAG_STOPPED and BLK_MQ_S_STOPPED
in the dm start and stop queue functions, only manipulate the latter
flag. Change blk_queue_stopped() tests into blk_mq_queue_stopped().
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Acked-by: Mike Snitzer <snitzer@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Most blk_mq_requeue_request() and blk_mq_add_to_requeue_list() calls
are followed by kicking the requeue list. Hence add an argument to
these two functions that allows to kick the requeue list. This was
proposed by Christoph Hellwig.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since blk_mq_requeue_work() no longer restarts stopped queues
canceling requeue work is no longer needed to prevent that a
stopped queue would be restarted. Hence remove this function.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since blk_mq_requeue_work() starts stopped queues and since
execution of this function can be scheduled after a queue has
been stopped it is not possible to stop queues without using
an additional state variable to track whether or not the queue
has been stopped. Hence modify blk_mq_requeue_work() such that it
does not start stopped queues. My conclusion after a review of
the blk_mq_stop_hw_queues() and blk_mq_{delay_,}kick_requeue_list()
callers is as follows:
* In the dm driver starting and stopping queues should only happen
if __dm_suspend() or __dm_resume() is called and not if the
requeue list is processed.
* In the SCSI core queue stopping and starting should only be
performed by the scsi_internal_device_block() and
scsi_internal_device_unblock() functions but not by any other
function. Although the blk_mq_stop_hw_queue() call in
scsi_queue_rq() may help to reduce CPU load if a LLD queue is
full, figuring out whether or not a queue should be restarted
when requeueing a command would require to introduce additional
locking in scsi_mq_requeue_cmd() to avoid a race with
scsi_internal_device_block(). Avoid this complexity by removing
the blk_mq_stop_hw_queue() call from scsi_queue_rq().
* In the NVMe core only the functions that call
blk_mq_start_stopped_hw_queues() explicitly should start stopped
queues.
* A blk_mq_start_stopped_hwqueues() call must be added in the
xen-blkfront driver in its blkif_recover() function.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Roger Pau Monné <roger.pau@citrix.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: James Bottomley <jejb@linux.vnet.ibm.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@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>
(and remove one layer of masking for the op_is_write call next to it).
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 write is the first operation on a disk and it happens not to be
aligned to page size, block layer sends read request first. If read
operation fails, the disk is set as failed as no attempt to fix the
error is made because array is in auto-readonly mode. Similarily, the
disk is set as failed for read-only array.
Take the same approach as in raid10. Don't fail the disk if array is in
readonly or auto-readonly mode. Try to redirect the request first and if
unsuccessful, return a read error.
Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>
As long as we recover one metadata block, we should write the empty metadata
write. The original code could make recovery corrupted if only one meta is
valid.
Reported-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Shaohua Li <shli@fb.com>
- A couple .request_fn request-based DM NULL pointer fixes
- A fix for a DM target reference count leak, on target load error, that
prevented associated DM target kernel module(s) from being removed
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Merge tag 'dm-4.9-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper fixes from Mike Snitzer:
- a couple DM raid and DM mirror fixes
- a couple .request_fn request-based DM NULL pointer fixes
- a fix for a DM target reference count leak, on target load error,
that prevented associated DM target kernel module(s) from being
removed
* tag 'dm-4.9-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
dm table: fix missing dm_put_target_type() in dm_table_add_target()
dm rq: clear kworker_task if kthread_run() returned an error
dm: free io_barrier after blk_cleanup_queue call
dm raid: fix activation of existing raid4/10 devices
dm mirror: use all available legs on multiple failures
dm mirror: fix read error on recovery after default leg failure
dm raid: fix compat_features validation
Now that we don't need the common flags to overflow outside the range
of a 32-bit type we can encode them the same way for both the bio and
request fields. This in addition allows us to place the operation
first (and make some room for more ops while we're at it) and to
stop having to shift around the operation values.
In addition this allows passing around only one value in the block layer
instead of two (and eventuall also in the file systems, but we can do
that later) and thus clean up a lot of code.
Last but not least this allows decreasing the size of the cmd_flags
field in struct request to 32-bits. Various functions passing this
value could also be updated, but I'd like to avoid the churn for now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
A lot of the REQ_* flags are only used on struct requests, and only of
use to the block layer and a few drivers that dig into struct request
internals.
This patch adds a new req_flags_t rq_flags field to struct request for
them, and thus dramatically shrinks the number of common requests. It
also removes the unfortunate situation where we have to fit the fields
from the same enum into 32 bits for struct bio and 64 bits for
struct request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Shaun Tancheff <shaun.tancheff@seagate.com>
Signed-off-by: Jens Axboe <axboe@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 superblock points to an invalid meta block, r5l_load_log will set
create_super with true and create an new superblock, this runtime path
would always happen if we do no writing I/O to this array since it was
created. Writing an empty meta block could avoid this unnecessary
action at the first time we created log superblock.
Another reason is for the corretness of log recovery. Currently we have
bellow code to guarantee log revocery to be correct.
if (ctx.seq > log->last_cp_seq + 1) {
int ret;
ret = r5l_log_write_empty_meta_block(log, ctx.pos, ctx.seq + 10);
if (ret)
return ret;
log->seq = ctx.seq + 11;
log->log_start = r5l_ring_add(log, ctx.pos, BLOCK_SECTORS);
r5l_write_super(log, ctx.pos);
} else {
log->log_start = ctx.pos;
log->seq = ctx.seq;
}
If we just created a array with a journal device, log->log_start and
log->last_checkpoint should all be 0, then we write three meta block
which are valid except mid one and supposed crash happened. The ctx.seq
would equal to log->last_cp_seq + 1 and log->log_start would be set to
position of mid invalid meta block after we did a recovery, this will
lead to problems which could be avoided with this patch.
Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Shaohua Li <shli@fb.com>
No initial operation was done to this field when we
load/recovery the log, it got assignment only when IO
to raid disk was finished. So r5l_quiesce may use wrong
next_checkpoint to reclaim log space, that would make
reclaimable space calculation confused.
Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: Shaohua Li <shli@fb.com>
This is the counterpart of raid10 fix. If a write error occurs, raid10
will try to rewrite the bio in small chunk size. If the rewrite fails,
raid10 will record the error in bad block. narrow_write_error will
always use WRITE for the bio, but actually it could be a discard. Since
discard bio hasn't payload, write the bio will cause different issues.
But discard error isn't fatal, we can safely ignore it. This is what
this patch does.
This issue should exist since discard is added, but only exposed with
recent arbitrary bio size feature.
Cc: Sitsofe Wheeler <sitsofe@gmail.com>
Cc: stable@vger.kernel.org (v3.6)
Signed-off-by: Shaohua Li <shli@fb.com>
If a write error occurs, raid1 will try to rewrite the bio in small
chunk size. If the rewrite fails, raid1 will record the error in bad
block. narrow_write_error will always use WRITE for the bio, but
actually it could be a discard. Since discard bio hasn't payload, write
the bio will cause different issues. But discard error isn't fatal, we
can safely ignore it. This is what this patch does.
This issue should exist since discard is added, but only exposed with
recent arbitrary bio size feature.
Reported-and-tested-by: Sitsofe Wheeler <sitsofe@gmail.com>
Cc: stable@vger.kernel.org (v3.6)
Signed-off-by: Shaohua Li <shli@fb.com>
dm_get_target_type() was previously called so any error returned from
dm_table_add_target() must first call dm_put_target_type(). Otherwise
the DM target module's reference count will leak and the associated
kernel module will be unable to be removed.
Also, leverage the fact that r is already -EINVAL and remove an extra
newline.
Fixes: 36a0456 ("dm table: add immutable feature")
Fixes: cc6cbe1 ("dm table: add always writeable feature")
Fixes: 3791e2f ("dm table: add singleton feature")
Cc: stable@vger.kernel.org # 3.2+
Signed-off-by: tang.junhui <tang.junhui@zte.com.cn>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
cleanup_mapped_device() calls kthread_stop() if kworker_task is
non-NULL. Currently the assigned value could be a valid task struct or
an error code (e.g -ENOMEM). Reset md->kworker_task to NULL if
kthread_run() returned an erorr.
Fixes: 7193a9defc ("dm rq: check kthread_run return for .request_fn request-based DM")
Cc: stable@vger.kernel.org # 4.8
Reported-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm_old_request_fn() has paths that access md->io_barrier. The party
destroying io_barrier should ensure that no future execution of
dm_old_request_fn() is possible. Move io_barrier destruction to below
blk_cleanup_queue() to ensure this and avoid a NULL pointer crash during
request-based DM device shutdown.
Cc: stable@vger.kernel.org # 4.3+
Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
dm-raid 1.9.0 fails to activate existing RAID4/10 devices that have the
old superblock format (which does not have takeover/reshaping support
that was added via commit 33e53f0685).
Fix validation path for old superblocks by reverting to the old raid4
layout and basing checks on mddev->new_{level,layout,...} members in
super_init_validation().
Cc: stable@vger.kernel.org # 4.8
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
When any leg(s) have failed, any read will cause a new operational
default leg to be selected and the read is resubmitted to it. If that
new default leg fails the read too, no other still accessible legs are
used to resubmit the read again -- thus failing the io.
Fix by allowing the read to get resubmitted until all operational legs
have been exhausted. Also, remove any details.bi_dev use as a flag.
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
If a default leg has failed, any read will cause a new operational
default leg to be selected and the read is resubmitted. But until now
the read will return failure even though it was successful due to
resubmission. The reason for this is bio->bi_error was not being
cleared before resubmitting the bio.
Fix by clearing bio->bi_error before resubmission.
Fixes: 4246a0b63b ("block: add a bi_error field to struct bio")
Cc: stable@vger.kernel.org # 4.3+
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
A good practice is to prefix the names of functions by the name
of the subsystem.
The kthread worker API is a mix of classic kthreads and workqueues. Each
worker has a dedicated kthread. It runs a generic function that process
queued works. It is implemented as part of the kthread subsystem.
This patch renames the existing kthread worker API to use
the corresponding name from the workqueues API prefixed by
kthread_:
__init_kthread_worker() -> __kthread_init_worker()
init_kthread_worker() -> kthread_init_worker()
init_kthread_work() -> kthread_init_work()
insert_kthread_work() -> kthread_insert_work()
queue_kthread_work() -> kthread_queue_work()
flush_kthread_work() -> kthread_flush_work()
flush_kthread_worker() -> kthread_flush_worker()
Note that the names of DEFINE_KTHREAD_WORK*() macros stay
as they are. It is common that the "DEFINE_" prefix has
precedence over the subsystem names.
Note that INIT() macros and init() functions use different
naming scheme. There is no good solution. There are several
reasons for this solution:
+ "init" in the function names stands for the verb "initialize"
aka "initialize worker". While "INIT" in the macro names
stands for the noun "INITIALIZER" aka "worker initializer".
+ INIT() macros are used only in DEFINE() macros
+ init() functions are used close to the other kthread()
functions. It looks much better if all the functions
use the same scheme.
+ There will be also kthread_destroy_worker() that will
be used close to kthread_cancel_work(). It is related
to the init() function. Again it looks better if all
functions use the same naming scheme.
+ there are several precedents for such init() function
names, e.g. amd_iommu_init_device(), free_area_init_node(),
jump_label_init_type(), regmap_init_mmio_clk(),
+ It is not an argument but it was inconsistent even before.
[arnd@arndb.de: fix linux-next merge conflict]
Link: http://lkml.kernel.org/r/20160908135724.1311726-1-arnd@arndb.de
Link: http://lkml.kernel.org/r/1470754545-17632-3-git-send-email-pmladek@suse.com
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Borislav Petkov <bp@suse.de>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In ecbfb9f118 ("dm raid: add raid level takeover support") a new
compatible feature flag was added. Validation for these compat_features
was added but this only passes for new raid mappings with this feature
flag. This causes previously created raid mappings to be failed at
import.
Check compat_features for the only valid combination.
Fixes: ecbfb9f118 ("dm raid: add raid level takeover support")
Cc: stable@vger.kernel.org # v4.8
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Pull blk-mq irq/cpu mapping updates from Jens Axboe:
"This is the block-irq topic branch for 4.9-rc. It's mostly from
Christoph, and it allows drivers to specify their own mappings, and
more importantly, to share the blk-mq mappings with the IRQ affinity
mappings. It's a good step towards making this work better out of the
box"
* 'for-4.9/block-irq' of git://git.kernel.dk/linux-block:
blk_mq: linux/blk-mq.h does not include all the headers it depends on
blk-mq: kill unused blk_mq_create_mq_map()
blk-mq: get rid of the cpumask in struct blk_mq_tags
nvme: remove the post_scan callout
nvme: switch to use pci_alloc_irq_vectors
blk-mq: provide a default queue mapping for PCI device
blk-mq: allow the driver to pass in a queue mapping
blk-mq: remove ->map_queue
blk-mq: only allocate a single mq_map per tag_set
blk-mq: don't redistribute hardware queues on a CPU hotplug event
. add support for delaying the requeue of requests; used by DM multipath
when all paths have failed and 'queue_if_no_path' is enabled
. DM cache improvements to speedup the loading metadata and the writing
of the hint array
. fix potential for a dm-crypt crash on device teardown
. remove dm_bufio_cond_resched() and just using cond_resched()
. change DM multipath to return a reservation conflict error
immediately; rather than failing the path and retrying (potentially
indefinitely)
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Merge tag 'dm-4.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm
Pull device mapper updates from Mike Snitzer:
- various fixes and cleanups for request-based DM core
- add support for delaying the requeue of requests; used by DM
multipath when all paths have failed and 'queue_if_no_path' is
enabled
- DM cache improvements to speedup the loading metadata and the writing
of the hint array
- fix potential for a dm-crypt crash on device teardown
- remove dm_bufio_cond_resched() and just using cond_resched()
- change DM multipath to return a reservation conflict error
immediately; rather than failing the path and retrying (potentially
indefinitely)
* tag 'dm-4.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm: (24 commits)
dm mpath: always return reservation conflict without failing over
dm bufio: remove dm_bufio_cond_resched()
dm crypt: fix crash on exit
dm cache metadata: switch to using the new cursor api for loading metadata
dm array: introduce cursor api
dm btree: introduce cursor api
dm cache policy smq: distribute entries to random levels when switching to smq
dm cache: speed up writing of the hint array
dm array: add dm_array_new()
dm mpath: delay the requeue of blk-mq requests while all paths down
dm mpath: use dm_mq_kick_requeue_list()
dm rq: introduce dm_mq_kick_requeue_list()
dm rq: reduce arguments passed to map_request() and dm_requeue_original_request()
dm rq: add DM_MAPIO_DELAY_REQUEUE to delay requeue of blk-mq requests
dm: convert wait loops to use autoremove_wake_function()
dm: use signal_pending_state() in dm_wait_for_completion()
dm: rename task state function arguments
dm: add two lockdep_assert_held() statements
dm rq: simplify dm_old_stop_queue()
dm mpath: check if path's request_queue is dying in activate_path()
...
Pull block layer updates from Jens Axboe:
"This is the main pull request for block layer changes in 4.9.
As mentioned at the last merge window, I've changed things up and now
do just one branch for core block layer changes, and driver changes.
This avoids dependencies between the two branches. Outside of this
main pull request, there are two topical branches coming as well.
This pull request contains:
- A set of fixes, and a conversion to blk-mq, of nbd. From Josef.
- Set of fixes and updates for lightnvm from Matias, Simon, and Arnd.
Followup dependency fix from Geert.
- General fixes from Bart, Baoyou, Guoqing, and Linus W.
- CFQ async write starvation fix from Glauber.
- Add supprot for delayed kick of the requeue list, from Mike.
- Pull out the scalable bitmap code from blk-mq-tag.c and make it
generally available under the name of sbitmap. Only blk-mq-tag uses
it for now, but the blk-mq scheduling bits will use it as well.
From Omar.
- bdev thaw error progagation from Pierre.
- Improve the blk polling statistics, and allow the user to clear
them. From Stephen.
- Set of minor cleanups from Christoph in block/blk-mq.
- Set of cleanups and optimizations from me for block/blk-mq.
- Various nvme/nvmet/nvmeof fixes from the various folks"
* 'for-4.9/block' of git://git.kernel.dk/linux-block: (54 commits)
fs/block_dev.c: return the right error in thaw_bdev()
nvme: Pass pointers, not dma addresses, to nvme_get/set_features()
nvme/scsi: Remove power management support
nvmet: Make dsm number of ranges zero based
nvmet: Use direct IO for writes
admin-cmd: Added smart-log command support.
nvme-fabrics: Add host_traddr options field to host infrastructure
nvme-fabrics: revise host transport option descriptions
nvme-fabrics: rework nvmf_get_address() for variable options
nbd: use BLK_MQ_F_BLOCKING
blkcg: Annotate blkg_hint correctly
cfq: fix starvation of asynchronous writes
blk-mq: add flag for drivers wanting blocking ->queue_rq()
blk-mq: remove non-blocking pass in blk_mq_map_request
blk-mq: get rid of manual run of queue with __blk_mq_run_hw_queue()
block: export bio_free_pages to other modules
lightnvm: propagate device_add() error code
lightnvm: expose device geometry through sysfs
lightnvm: control life of nvm_dev in driver
blk-mq: register device instead of disk
...
