linux-uconsole/drivers/md
NeilBrown 2b84883f74 md/raid6: Fix anomily when recovering a single device in RAID6.
[ Upstream commit 7471fb77ce ]

When recoverying a single missing/failed device in a RAID6,
those stripes where the Q block is on the missing device are
handled a bit differently.  In these cases it is easy to
check that the P block is correct, so we do.  This results
in the P block be destroy.  Consequently the P block needs
to be read a second time in order to compute Q.  This causes
lots of seeks and hurts performance.

It shouldn't be necessary to re-read P as it can be computed
from the DATA.  But we only compute blocks on missing
devices, since c337869d95 ("md: do not compute parity
unless it is on a failed drive").

So relax the change made in that commit to allow computing
of the P block in a RAID6 which it is the only missing that
block.

This makes RAID6 recovery run much faster as the disk just
"before" the recovering device is no longer seeking
back-and-forth.

Reported-by-tested-by: Brad Campbell <lists2009@fnarfbargle.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-22 09:23:25 +01:00
..
bcache bcache: don't attach backing with duplicate UUID 2018-03-18 11:17:49 +01:00
persistent-data dm btree: fix serious bug in btree_split_beneath() 2018-01-23 19:50:16 +01:00
bitmap.c md/bitmap: disable bitmap_resize for file-backed bitmaps. 2017-09-27 11:00:14 +02:00
bitmap.h md-cluster: Use a small window for resync 2015-10-12 01:32:05 -05:00
dm-bio-prison.c block: add a bi_error field to struct bio 2015-07-29 08:55:15 -06:00
dm-bio-prison.h dm bio prison: add dm_cell_promote_or_release() 2015-05-29 14:19:06 -04:00
dm-bio-record.h
dm-bufio.c dm bufio: fix shrinker scans when (nr_to_scan < retain_target) 2018-01-17 09:35:24 +01:00
dm-bufio.h
dm-builtin.c
dm-cache-block-types.h
dm-cache-metadata.c dm cache metadata: fail operations if fail_io mode has been established 2017-05-25 14:30:08 +02:00
dm-cache-metadata.h dm cache: make sure every metadata function checks fail_io 2016-04-12 09:08:40 -07:00
dm-cache-policy-cleaner.c - Revert a dm-multipath change that caused a regression for unprivledged 2015-11-04 21:19:53 -08:00
dm-cache-policy-internal.h dm cache: age and write back cache entries even without active IO 2015-06-11 17:13:01 -04:00
dm-cache-policy-mq.c dm: convert ffs to __ffs 2015-10-31 19:06:01 -04:00
dm-cache-policy-smq.c dm: convert ffs to __ffs 2015-10-31 19:06:01 -04:00
dm-cache-policy.c
dm-cache-policy.h dm cache: age and write back cache entries even without active IO 2015-06-11 17:13:01 -04:00
dm-cache-target.c dm cache: fix corruption seen when using cache > 2TB 2017-03-12 06:37:26 +01:00
dm-crypt.c dm crypt: mark key as invalid until properly loaded 2017-01-06 11:16:15 +01:00
dm-delay.c dm delay: document that offsets are specified in sectors 2015-10-31 19:06:05 -04:00
dm-era-target.c dm era: save spacemap metadata root after the pre-commit 2017-05-20 14:27:00 +02:00
dm-exception-store.c - Revert a dm-multipath change that caused a regression for unprivledged 2015-11-04 21:19:53 -08:00
dm-exception-store.h dm snapshot: fix hung bios when copy error occurs 2016-03-03 15:07:14 -08:00
dm-flakey.c dm flakey: return -EINVAL on interval bounds error in flakey_ctr() 2017-01-06 11:16:15 +01:00
dm-io.c dm io: fix duplicate bio completion due to missing ref count 2018-03-11 16:19:47 +01:00
dm-ioctl.c dm ioctl: prevent stack leak in dm ioctl call 2017-05-08 07:46:02 +02:00
dm-kcopyd.c mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
dm-linear.c dm linear: remove redundant target name from error messages 2015-10-31 19:06:03 -04:00
dm-log-userspace-base.c dm: drop NULL test before kmem_cache_destroy() and mempool_destroy() 2015-10-31 19:06:00 -04:00
dm-log-userspace-transfer.c
dm-log-userspace-transfer.h
dm-log-writes.c dm log writes: fix bug with too large bios 2016-10-07 15:23:47 +02:00
dm-log.c
dm-mpath.c dm mpath: check if path's request_queue is dying in activate_path() 2016-10-28 03:01:28 -04:00
dm-mpath.h
dm-path-selector.c
dm-path-selector.h
dm-queue-length.c
dm-raid.c dm raid: fix round up of default region size 2015-10-02 12:02:31 -04:00
dm-raid1.c dm mirror: fix read error on recovery after default leg failure 2016-11-10 16:36:35 +01:00
dm-region-hash.c dm: convert ffs to __ffs 2015-10-31 19:06:01 -04:00
dm-round-robin.c
dm-service-time.c
dm-snap-persistent.c dm snapshot: fix hung bios when copy error occurs 2016-03-03 15:07:14 -08:00
dm-snap-transient.c dm snapshot: fix hung bios when copy error occurs 2016-03-03 15:07:14 -08:00
dm-snap.c dm snapshot: disallow the COW and origin devices from being identical 2016-04-12 09:08:39 -07:00
dm-stats.c dm stats: fix a leaked s->histogram_boundaries array 2017-03-12 06:37:26 +01:00
dm-stats.h dm stats: support precise timestamps 2015-06-17 12:40:40 -04:00
dm-stripe.c Merge tag 'dm-4.3-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm 2015-09-02 16:35:26 -07:00
dm-switch.c dm switch: simplify conditional in alloc_region_table() 2015-10-31 19:06:06 -04:00
dm-sysfs.c
dm-table.c dm snapshot: disallow the COW and origin devices from being identical 2016-04-12 09:08:39 -07:00
dm-target.c
dm-thin-metadata.c dm thin metadata: THIN_MAX_CONCURRENT_LOCKS should be 6 2018-01-23 19:50:17 +01:00
dm-thin-metadata.h dm thin metadata: add dm_thin_remove_range() 2015-06-11 17:13:04 -04:00
dm-thin.c dm thin: fix race condition when destroying thin pool workqueue 2016-03-03 15:07:10 -08:00
dm-uevent.c
dm-uevent.h
dm-verity.c dm: refactor ioctl handling 2015-10-31 19:05:59 -04:00
dm-zero.c block: add a bi_error field to struct bio 2015-07-29 08:55:15 -06:00
dm.c dm: correctly handle chained bios in dec_pending() 2018-02-22 15:45:01 +01:00
dm.h block: kill merge_bvec_fn() completely 2015-08-13 12:31:57 -06:00
faulty.c block: add a bi_error field to struct bio 2015-07-29 08:55:15 -06:00
Kconfig dm raid: select the Kconfig option CONFIG_MD_RAID0 2017-05-25 14:30:07 +02:00
linear.c md/linear: shutup lockdep warnning 2017-10-21 17:09:05 +02:00
linear.h md linear: fix a race between linear_add() and linear_congested() 2017-03-12 06:37:30 +01:00
Makefile raid5: add basic stripe log 2015-10-24 17:16:19 +11:00
md-cluster.c md-cluster: free md_cluster_info if node leave cluster 2017-12-20 10:04:52 +01:00
md-cluster.h md-cluster: Fix adding of new disk with new reload code 2015-10-12 03:35:30 -05:00
md.c md: avoid warning for 32-bit sector_t 2018-02-25 11:03:44 +01:00
md.h md/raid: only permit hot-add of compatible integrity profiles 2016-02-17 12:30:57 -08:00
multipath.c md: multipath: don't hardcopy bio in .make_request path 2016-04-12 09:08:57 -07:00
multipath.h
raid0.c md/raid0: apply base queue limits *before* disk_stack_limits 2015-10-02 17:23:44 +10:00
raid0.h block: kill merge_bvec_fn() completely 2015-08-13 12:31:57 -06:00
raid1.c md: don't use flush_signals in userspace processes 2017-07-27 15:06:06 -07:00
raid1.h md-cluster: Use a small window for resync 2015-10-12 01:32:05 -05:00
raid5-cache.c raid5-cache: start raid5 readonly if journal is missing 2015-11-01 13:48:29 +11:00
raid5.c md/raid6: Fix anomily when recovering a single device in RAID6. 2018-03-22 09:23:25 +01:00
raid5.h RAID5: revert e9e4c377e2 to fix a livelock 2016-04-12 09:08:57 -07:00
raid10.c md/raid10: submit bio directly to replacement disk 2017-10-08 10:14:20 +02:00
raid10.h md/raid10: ensure device failure recorded before write request returns. 2015-08-31 19:43:45 +02:00