3462 Commits

Author SHA1 Message Date
Mike Snitzer
9d094eebd7 dm thin: optimize retry_bios_on_resume
Eliminate redundant should_error_unserviceable_bio check and error
loop.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:28 -05:00
Joe Thornber
ac4c3f34a9 dm thin: sort the deferred cells
Sort the cells in logical block order before processing each cell in
process_thin_deferred_cells().  This significantly improves the ondisk
layout on rotational storage, whereby improving read performance.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:28 -05:00
Joe Thornber
23ca2bb6c6 dm thin: direct dispatch when breaking sharing
This use of direct submission in process_shared_bio() reduces latency
for submitting bios in the shared cell by avoiding adding those bios to
the deferred list and waiting for the next iteration of the worker.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:28 -05:00
Joe Thornber
2d759a46b4 dm thin: remap the bios in a cell immediately
This use of direct submission in process_prepared_mapping() reduces
latency for submitting bios in a cell by avoiding adding those bios to
the deferred list and waiting for the next iteration of the worker.

But this direct submission exposes the potential for a race between
releasing a cell and incrementing deferred set.  Fix this by introducing
dm_cell_visit_release() and refactoring inc_remap_and_issue_cell()
accordingly.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:28 -05:00
Joe Thornber
a374bb217b dm thin: defer whole cells rather than individual bios
This avoids dropping the cell, so increases the probability that other
bios will collect within the cell, rather than being passed individually
to the worker.

Also add required process_cell and process_discard_cell error handling
wrappers and set associated pool-mode function pointers accordingly.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:28 -05:00
Mike Snitzer
452d7a620d dm thin: factor out remap_and_issue_overwrite
Purely cleanup of duplicated code, no functional change.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:28 -05:00
Joe Thornber
7a7e97ca58 dm thin: performance improvement to discard processing
When processing a discard bio, if the block is already quiesced do the
discard immediately rather than adding the mapping to a list for the
next iteration of the worker thread.

Discarding a fully provisioned 100G thin volume with 64k block size goes
from 860s to 95s with this change.

Clearly there's something wrong with the worker architecture, more
investigation needed.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:27 -05:00
Mike Snitzer
36f12aeb71 dm thin: implement thin_merge
Introduce thin_merge so that any additional constraints from the data
volume may be taken into account when determing the maximum number of
sectors that can be issued relative to the specified logical offset.

This is particularly important if/when the data volume is layered ontop
of a more sophisticated device (e.g. dm-raid or some other DM target).

Reviewed-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:27 -05:00
Mike Snitzer
148e51baf8 dm: improve documentation and code clarity in dm_merge_bvec
These code changes do not introduce a functional change.

But bio_add_page() will never attempt to build up a bio larger than
queue_max_sectors().  Similarly, bio_get_nr_vecs() is also bound by
queue_max_sectors().  Therefore, there is no point in allowing
dm_merge_bvec() to answer "how many sectors can a bio have at this
offset?" with anything larger than queue_max_sectors().  Using
queue_max_sectors() rather than BIO_MAX_SECTORS serves to more
accurately convey the limits that are being imposed.

Also, use unlikely() to clarify the fact that the defensive code in
dm_merge_bvec() relative to max_size going negative shouldn't ever
happen -- if it does happen there is a bug in the block layer for
requesting larger than dm_merge_bvec()'s initial response for a given
offset.  Also, update a comment in dm_merge_bvec() relative to
max_hw_sectors_kb.  And fix empty newline whitespace.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:27 -05:00
Mike Snitzer
604ea90641 dm thin: adjust max_sectors_kb based on thinp blocksize
Allows for filesystems to submit bios that are a factor of the thinp
blocksize, improving dm-thinp efficiency (particularly when the data
volume is RAID).

Also set io_min to max_sectors_kb if it is a factor of the thinp
blocksize.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:27 -05:00
Joe Thornber
7d327fe051 dm thin: throttle incoming IO
Throttle IO based on the time it's taking the worker to do one loop.
There were reports of hung task timeouts occuring and it was observed
that the excessively long avgqu-sz (as reported by iostat) was
contributing to these hung tasks.

Throttling definitely helps dm-thinp perform better under heavy IO load
(without being detremental by being overzealous).  It reduces avgqu-sz
drastically, e.g.: from 60K to ~6K, and even as low as 150 once metadata
is cached by bufio, when dirty_ratio=5, dirty_background_ratio=2.  And
avgqu-sz stays at or below 30K even with dirty_ratio=20,
dirty_background_ratio=10.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:27 -05:00
Joe Thornber
8a01a6af75 dm thin: prefetch missing metadata pages
Prefetch metadata at the start of the worker thread and then again every
128th bio processed from the deferred list.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:27 -05:00
Joe Thornber
4646015d7e dm transaction manager: add support for prefetching blocks of metadata
Introduce the dm_tm_issue_prefetches interface.  If you're using a
non-blocking clone the tm will build up a list of requested blocks that
weren't in core.  dm_tm_issue_prefetches will request those blocks to be
prefetched.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:26 -05:00
Joe Thornber
e5cfc69a51 dm thin metadata: change dm_thin_find_block to allow blocking, but not issuing, IO
This change is a prerequisite for allowing metadata to be prefetched.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:26 -05:00
Joe Thornber
a195db2d29 dm bio prison: switch to using a red black tree
Previously it was using a fixed sized hash table.  There are times
when very many concurrent cells are held (such as when processing a very
large discard).  When this happens the hash table performance becomes
very poor.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:26 -05:00
Joe Thornber
33096a7822 dm bufio: evict buffers that are past the max age but retain some buffers
These changes help keep metadata backed by dm-bufio in-core longer which
fixes reports of metadata churn in the face of heavy random IO workloads.

Before, bufio evicted all buffers older than DM_BUFIO_DEFAULT_AGE_SECS.
Having a device (e.g. dm-thinp or dm-cache) lose all metadata just
because associated buffers had been idle for some time is unfriendly.

Now, the user may now configure the number of bytes that bufio retains
using the 'retain_bytes' module parameter.  The default is 256K.

Also, the DM_BUFIO_WORK_TIMER_SECS and DM_BUFIO_DEFAULT_AGE_SECS
defaults were quite low so increase them (to 30 and 300 respectively).

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:26 -05:00
Joe Thornber
4e420c452b dm bufio: switch from a huge hash table to an rbtree
Converting over to using an rbtree eliminates a fixed 8MB allocation
from vmalloc space for the hash table.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-11-10 15:25:26 -05:00
Joe Thornber
9b460d3699 dm btree: fix a recursion depth bug in btree walking code
The walk code was using a 'ro_spine' to hold it's locked btree nodes.
But this data structure is designed for the rolling lock scheme, and
as such automatically unlocks blocks that are two steps up the call
chain.  This is not suitable for the simple recursive walk algorithm,
which retraces its steps.

This code is only used by the persistent array code, which in turn is
only used by dm-cache.  In order to trigger it you need to have a
mapping tree that is more than 2 levels deep; which equates to 8-16
million cache blocks.  For instance a 4T ssd with a very small block
size of 32k only just triggers this bug.

The fix just places the locked blocks on the stack, and stops using
the ro_spine altogether.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2014-11-10 15:23:58 -05:00
Joe Thornber
c822ed967c dm thin: grab a virtual cell before looking up the mapping
Avoids normal IO racing with discard.

Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2014-11-04 13:05:53 -05:00
Heinz Mauelshagen
d20c4b08be dm raid: fix inaccessible superblocks causing oops in configure_discard_support
Commit 48cf06bc5f ("dm raid: add discard support for RAID levels 4, 5
and 6") did not properly handle missing metadata device(s).  A failing
read of the superblock causes the metadata and data devices to be
removed from the dev array in struct raid_set, setting references to
both devices to NULL.  configure_discard_support() nonetheless tries to
access the data dev unconditionally causing an oops.

Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-10-29 14:53:27 -04:00
Heinz Mauelshagen
40d43c4b4c dm raid: ensure superblock's size matches device's logical block size
The dm-raid superblock (struct dm_raid_superblock) is padded to 512
bytes and that size is being used to read it in from the metadata
device into one preallocated page.

Reading or writing this on a 512-byte sector device works fine but on
a 4096-byte sector device this fails.

Set the dm-raid superblock's size to the logical block size of the
metadata device, because IO at that size is guaranteed too work.  Also
add a size check to avoid silent partial metadata loss in case the
superblock should ever grow past the logical block size or PAGE_SIZE.

[includes pointer math fix from Dan Carpenter]
Reported-by: "Liuhua Wang" <lwang@suse.com>
Signed-off-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2014-10-21 09:32:15 -04:00
Linus Torvalds
929254d8da . fix DM's long-standing excessive use of memory by leveraging the new
bioset_create_nobvec() interface when creating the DM's bioset
 
 . fix a few bugs in dm-bufio and dm-log-userspace
 
 . add DM core support for a DM multipath use-case that requires loading
   DM tables that contain devices that have failed (by allowing active
   and inactive DM tables to share dm_devs)
 
 . add discard support to the DM raid target; like MD raid456 the user
   must opt-in to raid456 discard support be specifying the
   devices_handle_discard_safely=Y module param.
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Merge tag 'dm-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device-mapper updates from Mike Snitzer:
 "I rebased the DM tree ontop of linux-block.git's 'for-3.18/core' at
  the beginning of October because DM core now depends on the newly
  introduced bioset_create_nobvec() interface.

  Summary:

   - fix DM's long-standing excessive use of memory by leveraging the
     new bioset_create_nobvec() interface when creating the DM's bioset

   - fix a few bugs in dm-bufio and dm-log-userspace

   - add DM core support for a DM multipath use-case that requires
     loading DM tables that contain devices that have failed (by
     allowing active and inactive DM tables to share dm_devs)

   - add discard support to the DM raid target; like MD raid456 the user
     must opt-in to raid456 discard support be specifying the
     devices_handle_discard_safely=Y module param"

* tag 'dm-3.18' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm log userspace: fix memory leak in dm_ulog_tfr_init failure path
  dm bufio: when done scanning return from __scan immediately
  dm bufio: update last_accessed when relinking a buffer
  dm raid: add discard support for RAID levels 4, 5 and 6
  dm raid: add discard support for RAID levels 1 and 10
  dm: allow active and inactive tables to share dm_devs
  dm mpath: stop queueing IO when no valid paths exist
  dm: use bioset_create_nobvec()
  dm: remove nr_iovecs parameter from alloc_tio()
2014-10-18 12:25:30 -07:00
Linus Torvalds
e75437fb93 Merge branch 'for-3.18/drivers' of git://git.kernel.dk/linux-block
Pull block layer driver update from Jens Axboe:
 "This is the block driver pull request for 3.18.  Not a lot in there
  this round, and nothing earth shattering.

   - A round of drbd fixes from the linbit team, and an improvement in
     asender performance.

   - Removal of deprecated (and unused) IRQF_DISABLED flag in rsxx and
     hd from Michael Opdenacker.

   - Disable entropy collection from flash devices by default, from Mike
     Snitzer.

   - A small collection of xen blkfront/back fixes from Roger Pau Monné
     and Vitaly Kuznetsov"

* 'for-3.18/drivers' of git://git.kernel.dk/linux-block:
  block: disable entropy contributions for nonrot devices
  xen, blkfront: factor out flush-related checks from do_blkif_request()
  xen-blkback: fix leak on grant map error path
  xen/blkback: unmap all persistent grants when frontend gets disconnected
  rsxx: Remove deprecated IRQF_DISABLED
  block: hd: remove deprecated IRQF_DISABLED
  drbd: use RB_DECLARE_CALLBACKS() to define augment callbacks
  drbd: compute the end before rb_insert_augmented()
  drbd: Add missing newline in resync progress display in /proc/drbd
  drbd: reduce lock contention in drbd_worker
  drbd: Improve asender performance
  drbd: Get rid of the WORK_PENDING macro
  drbd: Get rid of the __no_warn and __cond_lock macros
  drbd: Avoid inconsistent locking warning
  drbd: Remove superfluous newline from "resync_extents" debugfs entry.
  drbd: Use consistent names for all the bi_end_io callbacks
  drbd: Use better variable names
2014-10-18 12:12:45 -07:00
Linus Torvalds
88ed806abb md updates for 3.18
- a few minor bug fixes
 - quite a lot of code tidy-up and simplification
 - remove PRINT_RAID_DEBUG ioctl.  I'm fairly sure
   it is unused, and it isn't particularly useful.
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Merge tag 'md/3.18' of git://neil.brown.name/md

Pull md updates from Neil Brown:
 - a few minor bug fixes
 - quite a lot of code tidy-up and simplification
 - remove PRINT_RAID_DEBUG ioctl.  I'm fairly sure it is unused, and it
   isn't particularly useful.

* tag 'md/3.18' of git://neil.brown.name/md: (21 commits)
  lib/raid6: Add log level to printks
  md: move EXPORT_SYMBOL to after function in md.c
  md: discard PRINT_RAID_DEBUG ioctl
  md: remove MD_BUG()
  md: clean up 'exit' labels in md_ioctl().
  md: remove unnecessary test for MD_MAJOR in md_ioctl()
  md: don't allow "-sync" to be set for device in an active array.
  md: remove unwanted white space from md.c
  md: don't start resync thread directly from md thread.
  md: Just use RCU when checking for overlap between arrays.
  md: avoid potential long delay under pers_lock
  md: simplify export_array()
  md: discard find_rdev_nr in favour of find_rdev_nr_rcu
  md: use wait_event() to simplify md_super_wait()
  md: be more relaxed about stopping an array which isn't started.
  md/raid1: process_checks doesn't use its return value.
  md/raid5: fix init_stripe() inconsistencies
  md/raid10: another memory leak due to reshape.
  md: use set_bit/clear_bit instead of shift/mask for bi_flags changes.
  md/raid1: minor typos and reformatting.
  ...
2014-10-18 11:39:52 -07:00
Mikulas Patocka
9d28eb1244 dm bufio: change __GFP_IO to __GFP_FS in shrinker callbacks
The shrinker uses gfp flags to indicate what kind of operation can the
driver wait for. If __GFP_IO flag is present, the driver can wait for
block I/O operations, if __GFP_FS flag is present, the driver can wait on
operations involving the filesystem.

dm-bufio tested for __GFP_IO. However, dm-bufio can run on a loop block
device that makes calls into the filesystem. If __GFP_IO is present and
__GFP_FS isn't, dm-bufio could still block on filesystem operations if it
runs on a loop block device.

The change from __GFP_IO to __GFP_FS supposedly fixes one observed (though
unreproducible) deadlock involving dm-bufio and loop device.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2014-10-17 01:40:23 -04:00
Linus Torvalds
0429fbc0bd Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu
Pull percpu consistent-ops changes from Tejun Heo:
 "Way back, before the current percpu allocator was implemented, static
  and dynamic percpu memory areas were allocated and handled separately
  and had their own accessors.  The distinction has been gone for many
  years now; however, the now duplicate two sets of accessors remained
  with the pointer based ones - this_cpu_*() - evolving various other
  operations over time.  During the process, we also accumulated other
  inconsistent operations.

  This pull request contains Christoph's patches to clean up the
  duplicate accessor situation.  __get_cpu_var() uses are replaced with
  with this_cpu_ptr() and __this_cpu_ptr() with raw_cpu_ptr().

  Unfortunately, the former sometimes is tricky thanks to C being a bit
  messy with the distinction between lvalues and pointers, which led to
  a rather ugly solution for cpumask_var_t involving the introduction of
  this_cpu_cpumask_var_ptr().

  This converts most of the uses but not all.  Christoph will follow up
  with the remaining conversions in this merge window and hopefully
  remove the obsolete accessors"

* 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (38 commits)
  irqchip: Properly fetch the per cpu offset
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t -fix
  ia64: sn_nodepda cannot be assigned to after this_cpu conversion. Use __this_cpu_write.
  percpu: Resolve ambiguities in __get_cpu_var/cpumask_var_t
  Revert "powerpc: Replace __get_cpu_var uses"
  percpu: Remove __this_cpu_ptr
  clocksource: Replace __this_cpu_ptr with raw_cpu_ptr
  sparc: Replace __get_cpu_var uses
  avr32: Replace __get_cpu_var with __this_cpu_write
  blackfin: Replace __get_cpu_var uses
  tile: Use this_cpu_ptr() for hardware counters
  tile: Replace __get_cpu_var uses
  powerpc: Replace __get_cpu_var uses
  alpha: Replace __get_cpu_var
  ia64: Replace __get_cpu_var uses
  s390: cio driver &__get_cpu_var replacements
  s390: Replace __get_cpu_var uses
  mips: Replace __get_cpu_var uses
  MIPS: Replace __get_cpu_var uses in FPU emulator.
  arm: Replace __this_cpu_ptr with raw_cpu_ptr
  ...
2014-10-15 07:48:18 +02:00
Jan-Simon Möller
b610626523 crypto, dm: LLVMLinux: Remove VLAIS usage from dm-crypt
Replaced the use of a Variable Length Array In Struct (VLAIS) with a C99
compliant equivalent. This patch allocates the appropriate amount of memory
using a char array using the SHASH_DESC_ON_STACK macro.

The new code can be compiled with both gcc and clang.

Signed-off-by: Jan-Simon Möller <dl9pf@gmx.de>
Signed-off-by: Behan Webster <behanw@converseincode.com>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: pageexec@freemail.hu
Cc: gmazyland@gmail.com
Cc: "David S. Miller" <davem@davemloft.net>
2014-10-14 10:51:23 +02:00
NeilBrown
6c144d3164 md: move EXPORT_SYMBOL to after function in md.c
Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:29 +11:00
NeilBrown
2cbbca5e7c md: discard PRINT_RAID_DEBUG ioctl
All the interesting information printed by this ioctl
is provided in /proc/mdstat and/or sysfs.
So it isn't needed and isn't used and would be best if it didn't
exist.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:29 +11:00
NeilBrown
403df47888 md: remove MD_BUG()
Most of the places that call this are doing so pointlessly.
A couple of the others a best replaced with WARN_ON().

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:29 +11:00
NeilBrown
3adc28d85f md: clean up 'exit' labels in md_ioctl().
There are 4 labels and we only really need two.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:29 +11:00
NeilBrown
326eb17d73 md: remove unnecessary test for MD_MAJOR in md_ioctl()
unknown ioctls no longer get this deep into md_ioctl since
md_ioctl_valid() was introduced in 3.14.
So remove the test and the misleading comment.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:29 +11:00
NeilBrown
e1960f8c5c md: don't allow "-sync" to be set for device in an active array.
If an array is active, devices can be marked 'faulty', but simply
removing the 'sync' flag is wrong.  That only makes sense
for an array which is not active (and is probably only useful
for testing anyway).

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:29 +11:00
NeilBrown
f72ffdd686 md: remove unwanted white space from md.c
My editor shows much of this is RED.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:29 +11:00
NeilBrown
ac05f25669 md: don't start resync thread directly from md thread.
The main 'md' thread is needed for processing writes, so if it blocks
write requests could be delayed.

Starting a new thread requires some GFP_KERNEL allocations and so can
wait for writes to complete.  This can deadlock.

So instead, ask a workqueue to start the sync thread.
There is no particular rush for this to happen, so any work queue
will do.

MD_RECOVERY_RUNNING is used to ensure only one thread is started.

Reported-by: BillStuff <billstuff2001@sbcglobal.net>
Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:28 +11:00
NeilBrown
8b1afc3d67 md: Just use RCU when checking for overlap between arrays.
We don't really need the full mddev_lock here, and having to
drop it is messy.
RCU is enough to protect these lists.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:28 +11:00
Chao Yu
50bd377405 md: avoid potential long delay under pers_lock
printk may cause long time lapse if value of printk_delay in sysctl is
configured large by user. If register_md_personality takes long time to print in
spinlock pers_lock, we may encounter high CPU usage rate when there are other
pers_lock competitors who may be blocked to spin.
We can avoid this condition by moving printk out of coverage of pers_lock
spinlock.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:28 +11:00
NeilBrown
0638bb0e73 md: simplify export_array()
We don't really need that for_each loop, or those MD_BUGs.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:28 +11:00
NeilBrown
4878e9eb88 md: discard find_rdev_nr in favour of find_rdev_nr_rcu
Having both is a waste - just use the one.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:28 +11:00
NeilBrown
1967cd5616 md: use wait_event() to simplify md_super_wait()
md_super_wait is really just wait_event() open-coded.
So use the macro instead.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:28 +11:00
NeilBrown
9ba3b7f5d0 md: be more relaxed about stopping an array which isn't started.
In general we don't allow an array to be stopped if it is in use.
However if the array hasn't really been started yet, then any
apparent use is an anomily, probably due to 'udev' or similar
having a look to see what is there.

This means that if something goes wrong while assembling an array
it cannot reliably be un-assembled - STOP_ARRAY could fail.
There is no value here, so change do_md_stop() to succeed
despite concurrent opens if the array has not yet been
activated.  i.e. if ->pers is NULL.

Reported-by: "Baldysiak, Pawel" <pawel.baldysiak@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:28 +11:00
NeilBrown
c95e6385e8 md/raid1: process_checks doesn't use its return value.
process_checks() always returns '0', so change it to 'void'.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:28 +11:00
Markus Stockhausen
b8e6a15a1a md/raid5: fix init_stripe() inconsistencies
raid5: fix init_stripe() inconsistencies

1) remove_hash() is not necessary. We will only be called right after
   get_free_stripe(). There we have already a call to remove_hash().

2) Tracing prints out the sector of the freed stripe and not the sector
   that we want to initialize.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:28 +11:00
NeilBrown
c4796e215f md/raid10: another memory leak due to reshape.
Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-14 13:08:28 +11:00
Linus Torvalds
faafcba3b5 Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
 "The main changes in this cycle were:

   - Optimized support for Intel "Cluster-on-Die" (CoD) topologies (Dave
     Hansen)

   - Various sched/idle refinements for better idle handling (Nicolas
     Pitre, Daniel Lezcano, Chuansheng Liu, Vincent Guittot)

   - sched/numa updates and optimizations (Rik van Riel)

   - sysbench speedup (Vincent Guittot)

   - capacity calculation cleanups/refactoring (Vincent Guittot)

   - Various cleanups to thread group iteration (Oleg Nesterov)

   - Double-rq-lock removal optimization and various refactorings
     (Kirill Tkhai)

   - various sched/deadline fixes

  ... and lots of other changes"

* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (72 commits)
  sched/dl: Use dl_bw_of() under rcu_read_lock_sched()
  sched/fair: Delete resched_cpu() from idle_balance()
  sched, time: Fix build error with 64 bit cputime_t on 32 bit systems
  sched: Improve sysbench performance by fixing spurious active migration
  sched/x86: Fix up typo in topology detection
  x86, sched: Add new topology for multi-NUMA-node CPUs
  sched/rt: Use resched_curr() in task_tick_rt()
  sched: Use rq->rd in sched_setaffinity() under RCU read lock
  sched: cleanup: Rename 'out_unlock' to 'out_free_new_mask'
  sched: Use dl_bw_of() under RCU read lock
  sched/fair: Remove duplicate code from can_migrate_task()
  sched, mips, ia64: Remove __ARCH_WANT_UNLOCKED_CTXSW
  sched: print_rq(): Don't use tasklist_lock
  sched: normalize_rt_tasks(): Don't use _irqsave for tasklist_lock, use task_rq_lock()
  sched: Fix the task-group check in tg_has_rt_tasks()
  sched/fair: Leverage the idle state info when choosing the "idlest" cpu
  sched: Let the scheduler see CPU idle states
  sched/deadline: Fix inter- exclusive cpusets migrations
  sched/deadline: Clear dl_entity params when setscheduling to different class
  sched/numa: Kill the wrong/dead TASK_DEAD check in task_numa_fault()
  ...
2014-10-13 16:23:15 +02:00
Pavitra Kumar
a3f2af2547 dm stripe: fix potential for leak in stripe_ctr error path
Fix a potential struct stripe_c leak that would occur if the
chunk_size exceeded the maximum allowed by dm_set_target_max_io_len
(UINT_MAX).  However, in practice there is no possibility of this
occuring given that chunk_size is of type uint32_t.  But it is good to
fix this to future-proof in case dm_set_target_max_io_len's
implementation were to change.

Signed-off-by: Pavitra Kumar <pavitrak@nvidia.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
2014-10-10 22:05:18 -04:00
NeilBrown
3fd83717e4 md: use set_bit/clear_bit instead of shift/mask for bi_flags changes.
Using {set,clear}_bit is more consistent than shifting and masking.

No functional change.

Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-09 10:07:04 +11:00
NeilBrown
5965b642ff md/raid1: minor typos and reformatting.
Signed-off-by: NeilBrown <neilb@suse.de>
2014-10-09 10:07:04 +11:00
NeilBrown
4b5060ddae md/bitmap: always wait for writes on unplug.
If two threads call bitmap_unplug at the same time, then
one might schedule all the writes, and the other might
decide that it doesn't need to wait.  But really it does.

It rarely hurts to wait when it isn't absolutely necessary,
and the current code doesn't really focus on 'absolutely necessary'
anyway.  So just wait always.

This can potentially lead to data corruption if a crash happens
at an awkward time and data was written before the bitmap was
updated.  It is very unlikely, but this should go to -stable
just to be safe.  Appropriate for any -stable.

Signed-off-by: NeilBrown <neilb@suse.de>
Cc: stable@vger.kernel.org (please delay until 3.18 is released)
2014-10-09 10:07:04 +11:00
Alexey Khoroshilov
56ec16cb1e dm log userspace: fix memory leak in dm_ulog_tfr_init failure path
If cn_add_callback() fails in dm_ulog_tfr_init(), it does not
deallocate prealloced memory but calls cn_del_callback().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Reviewed-by: Jonathan Brassow <jbrassow@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
2014-10-05 20:03:38 -04:00