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| author | Mike Snitzer <snitzer@redhat.com> | 2015-03-11 20:01:09 +0100 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2015-04-15 18:10:17 +0200 |
| commit | 17e149b8f73ba116e71e25930dd6f2eb3828792d (patch) | |
| tree | 6407112dbb113ffeebfd0620df27d4f67cd27ed1 /Documentation/ABI | |
| parent | dm: optimize dm_mq_queue_rq to _not_ use kthread if using pure blk-mq (diff) | |
| download | linux-17e149b8f73ba116e71e25930dd6f2eb3828792d.tar.xz linux-17e149b8f73ba116e71e25930dd6f2eb3828792d.zip | |
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>
Diffstat (limited to 'Documentation/ABI')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-block-dm | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-block-dm b/Documentation/ABI/testing/sysfs-block-dm index ac4b6fe245d9..f9f2339b9a0a 100644 --- a/Documentation/ABI/testing/sysfs-block-dm +++ b/Documentation/ABI/testing/sysfs-block-dm @@ -37,3 +37,11 @@ Description: Allow control over how long a request that is a accounting. This attribute is not applicable to bio-based DM devices so it will only ever report 0 for them. + +What: /sys/block/dm-<num>/dm/use_blk_mq +Date: March 2015 +KernelVersion: 4.1 +Contact: dm-devel@redhat.com +Description: Request-based Device-mapper blk-mq I/O path mode. + Contains the value 1 if the device is using blk-mq. + Otherwise it contains 0. Read-only attribute. |