linux/block
Tejun Heo 5a5bafdc39 elevator: clear auxiliary data earlier during elevator switch
Elevator switch tries hard to keep as much as context until new
elevator is ready so that it can revert to the original state if
initializing the new elevator fails for some reason.  Unfortunately,
with more auxiliary contexts to manage, this makes elevator init and
exit paths too complex and fragile.

This patch makes elevator_switch() unregister the current elevator and
flush icq's before start initializing the new one.  As we still keep
the old elevator itself, the only difference is that we lose icq's on
rare occassions of switching failure, which isn't critical at all.

Note that this makes explicit elevator parameter to
elevator_init_queue() and __elv_register_queue() unnecessary as they
always can use the current elevator.

This patch enables block cgroup cleanups.

-v2: blk_add_trace_msg() prints elevator name from @new_e instead of
     @e->type as the local variable no longer exists.  This caused
     build failure on CONFIG_BLK_DEV_IO_TRACE.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2012-03-06 21:27:21 +01:00
..
partitions separate partition format handling from generic code 2012-01-03 22:54:06 -05:00
blk-cgroup.c blkcg: make CONFIG_BLK_CGROUP bool 2012-03-06 21:27:21 +01:00
blk-cgroup.h blkcg: make CONFIG_BLK_CGROUP bool 2012-03-06 21:27:21 +01:00
blk-core.c block: blk-throttle should be drained regardless of q->elevator 2012-03-06 21:24:55 +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: exit_io_context() should call elevator_exit_icq_fn() 2012-02-15 09:45:53 +01:00
blk-iopoll.c tree-wide: fix assorted typos all over the place 2009-12-04 15:39:55 +01:00
blk-lib.c block: fix patch import error in max_discard_sectors check 2011-07-23 20:34:59 +02:00
blk-map.c block: re-use existing 'reading' variable instead of checking direction again 2011-12-21 15:27:24 +01:00
blk-merge.c block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions 2012-02-08 09:19:38 +01:00
blk-settings.c block: Introduce blk_set_stacking_limits function 2012-01-11 16:27:11 +01:00
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: fix blk_queue_end_tag() 2011-12-29 09:16:28 +01:00
blk-throttle.c block: add blk_queue_dead() 2011-12-14 00:33:37 +01:00
blk-timeout.c fault-injection: add ability to export fault_attr in arbitrary directory 2011-08-03 14:25:20 -10:00
blk.h block: separate out blk_rq_merge_ok() and blk_try_merge() from elevator functions 2012-02-08 09:19:38 +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 bsg: fix sysfs link remove warning 2012-02-08 20:02:03 +01:00
cfq-iosched.c cfq: don't register propio policy if !CONFIG_CFQ_GROUP_IOSCHED 2012-03-06 21:27:21 +01:00
cfq.h blk-cgroup: Add unaccounted time to timeslice_used. 2011-03-12 16:54:00 +01:00
compat_ioctl.c block: Add BLKROTATIONAL ioctl 2012-01-11 16:29:31 +01:00
deadline-iosched.c block, cfq: move icq cache management to block core 2011-12-14 00:33:42 +01:00
elevator.c elevator: clear auxiliary data earlier during elevator switch 2012-03-06 21:27:21 +01:00
genhd.c Block: use a freezable workqueue for disk-event polling 2012-03-02 10:51:00 +01:00
ioctl.c Merge branch 'for-3.3/core' of git://git.kernel.dk/linux-block 2012-01-15 12:24:45 -08:00
Kconfig move fs/partitions to block/ 2012-01-03 22:54:06 -05:00
Kconfig.iosched blkcg: make CONFIG_BLK_CGROUP bool 2012-03-06 21:27:21 +01:00
Makefile separate partition format handling from generic code 2012-01-03 22:54:06 -05:00
noop-iosched.c block, cfq: move icq cache management to block core 2011-12-14 00:33:42 +01:00
partition-generic.c block: Fix NULL pointer dereference in sd_revalidate_disk 2012-03-02 10:38:33 +01:00
scsi_ioctl.c block: fail SCSI passthrough ioctls on partition devices 2012-01-14 15:07:24 -08:00