Mikulas Patocka c6ea41fbbe dm kcopyd: preallocate sub jobs to avoid deadlock ... There's a possible theoretical deadlock in dm-kcopyd because multiple allocations from the same mempool are required to finish a request. Avoid this by preallocating sub jobs. There is a mempool of 512 entries. Each request requires up to 9 entries from the mempool. If we have at least 57 concurrent requests running, the mempool may overflow and mempool allocations may start blocking until another entry is freed to the mempool. Because the same thread is used to free entries to the mempool and allocate entries from the mempool, this may result in a deadlock. This patch changes it so that one mempool entry contains all 9 "struct kcopyd_job" required to fulfill the whole request. The allocation is done only once in dm_kcopyd_copy and no further mempool allocations are done during request processing. If dm_kcopyd_copy is not run in the completion thread, this implementation is deadlock-free. MIN_JOBS needs reducing accordingly and we've chosen to reduce it further to 8. Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com>		2011-05-29 13:03:00 +01:00
..
bitmap.c	md/bitmap: fix saving of events_cleared and other state.	2011-05-11 14:26:30 +10:00
bitmap.h	Fix common misspellings	2011-03-31 11:26:23 -03:00
dm-bio-record.h	dm: preserve bi_io_vec when resubmitting bios	2009-04-02 19:55:23 +01:00
dm-crypt.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm	2011-03-25 20:51:44 -07:00
dm-delay.c	dm: convert workqueues to alloc_ordered	2011-01-13 19:59:57 +00:00
dm-exception-store.c	dm snapshot: test chunk size against both origin and snapshot	2010-08-12 04:13:51 +01:00
dm-exception-store.h	dm snapshot: test chunk size against both origin and snapshot	2010-08-12 04:13:51 +01:00
dm-flakey.c	dm: add flakey target	2011-03-24 13:54:24 +00:00
dm-io.c	block: kill off REQ_UNPLUG	2011-03-10 08:52:27 +01:00
dm-ioctl.c	dm ioctl: add flag to wipe buffers for secure data	2011-03-24 13:54:30 +00:00
dm-kcopyd.c	dm kcopyd: preallocate sub jobs to avoid deadlock	2011-05-29 13:03:00 +01:00
dm-linear.c	dm: use dm_target_offset macro	2010-08-12 04:14:11 +01:00
dm-log-userspace-base.c	dm log userspace: add version number to comms	2011-01-13 19:59:52 +00:00
dm-log-userspace-transfer.c	netlink: kill eff_cap from struct netlink_skb_parms	2011-03-03 13:32:07 -08:00
dm-log-userspace-transfer.h	dm log: userspace add luid to distinguish between concurrent log instances	2009-09-04 20:40:34 +01:00
dm-log.c	Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm	2011-03-25 20:51:44 -07:00
dm-mpath.c	dm mpath: do not fail paths after integrity errors	2011-05-29 13:02:55 +01:00
dm-mpath.h	dm mpath: remove is_active from struct dm_path	2008-10-10 13:36:58 +01:00
dm-path-selector.c	dm: path selector use module refcount directly	2009-04-02 19:55:27 +01:00
dm-path-selector.h	dm mpath: add start_io and nr_bytes to path selectors	2009-06-22 10:12:27 +01:00
dm-queue-length.c	dm mpath: add queue length load balancer	2009-06-22 10:12:27 +01:00
dm-raid.c	md/dm - remove remains of plug_fn callback.	2011-04-18 18:25:41 +10:00
dm-raid1.c	block: remove per-queue plugging	2011-03-10 08:52:07 +01:00
dm-region-hash.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
dm-round-robin.c	dm mpath: add start_io and nr_bytes to path selectors	2009-06-22 10:12:27 +01:00
dm-service-time.c	include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h	2010-03-30 22:02:32 +09:00
dm-snap-persistent.c	dm snapshot: persistent make metadata_wq multithreaded	2011-01-13 19:59:59 +00:00
dm-snap-transient.c	dm snapshot: move cow ref from exception store to snap core	2009-12-10 23:52:12 +00:00
dm-snap.c	dm: fix opening log and cow devices for read only tables	2011-03-24 13:52:14 +00:00
dm-stripe.c	dm stripe: implement merge method	2011-03-24 13:54:35 +00:00
dm-sysfs.c	Driver core: Constify struct sysfs_ops in struct kobj_type	2010-03-07 17:04:49 -08:00
dm-table.c	dm table: reject devices without request fns	2011-05-29 13:02:52 +01:00
dm-target.c	dm: error return error for discards	2010-08-12 04:14:14 +01:00
dm-uevent.c	dm table: remove dm_get from dm_table_get_md	2010-03-06 02:29:52 +00:00
dm-uevent.h	dm: uevent generate events	2007-10-20 02:01:26 +01:00
dm-zero.c	dm: zero silently drop discards	2010-08-12 04:14:12 +01:00
dm.c	block: fix non-atomic access to genhd inflight structures	2011-03-22 08:35:35 +01:00
dm.h	block: Require subsystems to explicitly allocate bio_set integrity mempool	2011-03-17 11:11:05 +01:00
faulty.c	Fix common misspellings	2011-03-31 11:26:23 -03:00
Kconfig	dm: add flakey target	2011-03-24 13:54:24 +00:00
linear.c	block: Require subsystems to explicitly allocate bio_set integrity mempool	2011-03-17 11:11:05 +01:00
linear.h	md/linear: use call_rcu to free obsolete 'conf' structures.	2009-06-18 08:49:42 +10:00
Makefile	dm: add flakey target	2011-03-24 13:54:24 +00:00
md.c	md: allow resync_start to be set while an array is active.	2011-05-11 15:52:21 +10:00
md.h	md: provide generic support for handling unplug callbacks.	2011-04-18 18:25:42 +10:00
multipath.c	md: make error_handler functions more uniform and correct.	2011-05-11 14:38:44 +10:00
multipath.h	md/multipath: discard ->working_disks in favour of ->degraded	2011-05-11 14:38:02 +10:00
raid0.c	block: Require subsystems to explicitly allocate bio_set integrity mempool	2011-03-17 11:11:05 +01:00
raid0.h	md: fix handling of array level takeover that re-arranges devices.	2010-06-24 13:33:24 +10:00
raid1.c	md: allow resync_start to be set while an array is active.	2011-05-11 15:52:21 +10:00
raid1.h	md/raid1: improve handling of pages allocated for write-behind.	2011-05-11 14:51:19 +10:00
raid5.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2011-05-23 09:12:26 -07:00
raid5.h	md - remove old plugging code.	2011-04-18 18:25:42 +10:00
raid10.c	md/raid10: reformat some loops with less indenting.	2011-05-11 14:54:41 +10:00
raid10.h	Fix common misspellings	2011-03-31 11:26:23 -03:00