dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr
authorMike Snitzer <snitzer@redhat.com>
Wed, 11 Mar 2015 19:01:09 +0000 (15:01 -0400)
committerMike Snitzer <snitzer@redhat.com>
Wed, 15 Apr 2015 16:10:17 +0000 (12:10 -0400)
commit17e149b8f73ba116e71e25930dd6f2eb3828792d
tree6407112dbb113ffeebfd0620df27d4f67cd27ed1
parent022333427a8aa4ccb318a9db90cea4e69ca1826b
dm: add 'use_blk_mq' module param and expose in per-device ro sysfs attr

Request-based DM's blk-mq support defaults to off; but a user can easily
change the default using the dm_mod.use_blk_mq module/boot option.

Also, you can check what mode a given request-based DM device is using
with: cat /sys/block/dm-X/dm/use_blk_mq

This change enabled further cleanup and reduced work (e.g. the
md->io_pool and md->rq_pool isn't created if using blk-mq).

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Documentation/ABI/testing/sysfs-block-dm
drivers/md/Kconfig
drivers/md/dm-sysfs.c
drivers/md/dm-table.c
drivers/md/dm.c
drivers/md/dm.h