Re: [PATCH v4 0/5] Fix I/O priority lost in device-mapper

[Eric Biggers]

On Tue, Dec 12, 2023 at 07:11:45PM +0800, Hongyu Jin wrote:
> From: Hongyu Jin <hongyu.jin@xxxxxxxxxx>
> 
> A high-priority task obtains data from the dm-verity device using the
> RT IO priority, during the verification, the IO reading FEC and hash
> by kworker loses the RT priority and is blocked by the low-priority IO.
> dm-crypt has the same problem in the process of writing data.
> 
> 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.
> 

What commit does this patch series apply to?

- Eric