Tejun Heo fd63836811 block: an exiting task should be allowed to create io_context ...

While fixing io_context creation / task exit race condition,
6e736be7f2 "block: make ioc get/put interface more conventional and
fix race on alloction" also prevented an exiting (%PF_EXITING) task
from creating its own io_context.  This is incorrect as exit path may
issue IOs, e.g. from exit_files(), and if those IOs are the first ones
issued by the task, io_context needs to be created to process the IOs.

Combined with the existing problem of io_context / io_cq creation
failure having the possibility of stalling IO, this problem results in
deterministic full IO lockup with certain workloads.

Fix it by allowing io_context creation regardless of %PF_EXITING for
%current.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Andrew Morton <akpm@linux-foundation.org>
Reported-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

2011-12-25 14:29:14 +01:00

..

blk-cgroup.c

block, cfq: unlink cfq_io_context's immediately

2011-12-14 00:33:39 +01:00

blk-cgroup.h

block: fix a typo in the blk-cgroup.h file

2011-10-24 16:08:38 +02:00

blk-core.c

block, cfq: move icq creation and rq->elv.icq association to block core

2011-12-14 00:33:42 +01:00

blk-exec.c

block: add missing blk_queue_dead() checks

2011-12-14 00:33:37 +01:00

blk-flush.c

blk-flush: move the queue kick into

2011-10-24 16:24:31 +02:00

blk-integrity.c

block: add export.h to files using EXPORT_SYMBOL/THIS_MODULE macros

2011-10-31 19:31:12 -04:00

blk-ioc.c

block: an exiting task should be allowed to create io_context

2011-12-25 14:29:14 +01:00

blk-iopoll.c

…

blk-lib.c

…

blk-map.c

block: Always check length of all iov entries in blk_rq_map_user_iov()

2011-11-13 19:58:09 +01:00

blk-merge.c

…

blk-settings.c

…

blk-softirq.c

block: Don't check QUEUE_FLAG_SAME_COMP in __blk_complete_request

2011-09-14 09:31:01 +02:00

blk-sysfs.c

block, cfq: move io_cq exit/release to blk-ioc.c

2011-12-14 00:33:42 +01:00

blk-tag.c

block: warn if tag is greater than real_max_depth.

2011-10-25 10:20:05 +02:00

blk-throttle.c

block: add blk_queue_dead()

2011-12-14 00:33:37 +01:00

blk-timeout.c

…

blk.h

block, cfq: move icq creation and rq->elv.icq association to block core

2011-12-14 00:33:42 +01:00

bsg-lib.c

block: Change module.h -> export.h in bsg-lib.c

2011-10-31 19:31:13 -04:00

bsg.c

block: misc updates to blk_get_queue()

2011-12-14 00:33:38 +01:00

cfq-iosched.c

block, cfq: fix empty queue crash caused by request merge

2011-12-16 14:00:22 +01:00

cfq.h

…

compat_ioctl.c

…

deadline-iosched.c

block, cfq: move icq cache management to block core

2011-12-14 00:33:42 +01:00

elevator.c

block: recursive merge requests

2011-12-16 14:00:31 +01:00

genhd.c

block: misc updates to blk_get_queue()

2011-12-14 00:33:38 +01:00

ioctl.c

Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

2011-11-06 19:44:47 -08:00

Kconfig

…

Kconfig.iosched

…

Makefile

…

noop-iosched.c

block, cfq: move icq cache management to block core

2011-12-14 00:33:42 +01:00

scsi_ioctl.c

block: drop unnecessary blk_get/put_queue() in scsi_cmd_ioctl() and blk_get_tg()

2011-10-19 14:31:25 +02:00