On Thu, 23 Jun 2022 09:48:26 +0200, Jan Kara wrote:
> Commit e70344c05995 ("block: fix default IO priority handling")
> introduced an inconsistency in get_current_ioprio() that tasks without
> IO context return IOPRIO_DEFAULT priority while tasks with freshly
> allocated IO context will return 0 (IOPRIO_CLASS_NONE/0) IO priority.
> Tasks without IO context used to be rare before 5a9d041ba2f6 ("block:
> move io_context creation into where it's needed") but after this commit
> they became common because now only BFQ IO scheduler setups task's IO
> context. Similar inconsistency is there for get_task_ioprio() so this
> inconsistency is now exposed to userspace and userspace will see
> different IO priority for tasks operating on devices with BFQ compared
> to devices without BFQ. Furthemore the changes done by commit
> e70344c05995 change the behavior when no IO priority is set for BFQ IO
> scheduler which is also documented in ioprio_set(2) manpage:
>
> [...]
Applied, thanks!
[1/9] block: fix default IO priority handling again
commit: f0f5a5e24fa5412f187f429232334ad6832d1a66
[2/9] block: Return effective IO priority from get_current_ioprio()
commit: 93fd10125cd702d86f1c4005349b54eeb3c02af3
[3/9] block: Generalize get_current_ioprio() for any task
commit: 86f80bd5f639921c59afb113fa3ebb3ccb46be84
[4/9] block: Make ioprio_best() static
commit: c85fb98c51a66ff7346f2e12f6c20fb4f60de812
[5/9] block: Fix handling of tasks without ioprio in ioprio_get(2)
commit: caf2c269be20c536009ccd815a4e493d0c6c6634
[6/9] blk-ioprio: Remove unneeded field
commit: d2adb01a5bcbe36bc05fbb383028da755f7a919b
[7/9] blk-ioprio: Convert from rqos policy to direct call
commit: 8f3d8d7f56aba4c6171e48b107b9167255044653
[8/9] block: Initialize bio priority earlier
commit: 92c3dfe1cfce7dd7cf6cd32b78b05885d824656e
[9/9] block: Always initialize bio IO priority on submit
commit: 71ad7aabb8968164b1963fff7216b225fdd80f84
Best regards,
--
Jens Axboe
