Re: [PATCH v8 0/5] Fix I/O priority lost in device-mapper

[Mikulas Patocka <mpatocka@redhat.com>]

The patchset seems OK to me.

Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>


On Wed, 24 Jan 2024, Hongyu Jin wrote:

> From: Hongyu Jin <hongyu.jin@unisoc.com>
> 
> High-priority tasks get data from dm-verity devices via RT IO priority,
> I/O will lose RT priority when reading FEC and hash values via kworker
> submission IO during verification, and the verification phase may be
> blocked by low-priority IO.
> 
> Dm-crypt has the same problem in the data writing process.
> 
> This is because io_context and blkcg are missing.
> 
> Move bio_set_ioprio() into submit_bio():
> 1. Only call bio_set_ioprio() once to set the priority of original bio,
>    the bio that cloned and splited from original bio will auto inherit
>    the priority of original bio in clone process.
> 
> 2. Make the IO priority of the original bio to be passed to dm,
>    and the dm target inherits the IO priority as needed.
> 
> Changes in v8:
>   - Rebase patch 1 on commit 7ed2632ec7d7
> Changes in v7:
>   - Modify patch 4: change dm-verity-fec.c
> Changes in v6:
>   - Rebase patch and resolve conflict for patch 1, 3, 4
>   - Modify patch 4: fec_read_parity() follow the priority of original
>     bio
>   - Update commit message
> Changes in v5:
>   - Rewrite patch 2, add ioprio parameter in dm_io();
>   - Modify dm_io() in patch 3
> Changes in v4:
>   - Modify commit message by Suggestion
>   - Modify patch for dm-crypt
> Changes in v3:
>   - Split patch for device-mapper
>   - Add patch to fix dm-crypy I/O priority question
>   - Add block patch to review together
>   - Fix some error in v2 patch
> Changes in v2:
>   - Add ioprio field in struct dm_io_region
>   - Initial struct dm_io_region::ioprio to IOPRIO_DEFAULT
>   - Add two interface
> 
> 
> Hongyu Jin (5):
>   block: Fix bio IO priority setting
>   dm: Support I/O priority for dm_io()
>   dm-bufio: Support I/O priority
>   dm verity: Fix I/O priority lost when read FEC and hash
>   dm-crypt: Fix lost ioprio when queuing write bios
> 
>  block/blk-core.c                              | 10 +++++
>  block/blk-mq.c                                | 10 -----
>  drivers/md/dm-bufio.c                         | 43 +++++++++++--------
>  drivers/md/dm-crypt.c                         |  1 +
>  drivers/md/dm-ebs-target.c                    |  8 ++--
>  drivers/md/dm-integrity.c                     | 12 +++---
>  drivers/md/dm-io.c                            | 23 +++++-----
>  drivers/md/dm-kcopyd.c                        |  4 +-
>  drivers/md/dm-log.c                           |  4 +-
>  drivers/md/dm-raid1.c                         |  6 +--
>  drivers/md/dm-snap-persistent.c               |  8 ++--
>  drivers/md/dm-verity-fec.c                    | 21 +++++----
>  drivers/md/dm-verity-target.c                 | 13 ++++--
>  drivers/md/dm-writecache.c                    |  8 ++--
>  drivers/md/persistent-data/dm-block-manager.c |  6 +--
>  include/linux/dm-bufio.h                      |  5 ++-
>  include/linux/dm-io.h                         |  3 +-
>  17 files changed, 102 insertions(+), 83 deletions(-)
> 
> 
> base-commit: 7ed2632ec7d72e926b9e8bcc9ad1bb0cd37274bf
> -- 
> 2.34.1