Re: [RFC V2 0/6] blk: make blk-rq-qos policies pluggable and modular

[Chaitanya Kulkarni]

Wang Jianchao (Kuaishou),

On 2/15/22 04:36, Wang Jianchao (Kuaishou) wrote:
> Hi Jens
> 
> blk-rq-qos is a standalone framework out of io-sched and can be used to
> control or observe the IO progress in block-layer with hooks. blk-rq-qos
> is a great design but right now, it is totally fixed and built-in and shut
> out peoples who want to use it with external module.
> 
> This patchset attempts to make blk-rq-qos framework pluggable and modular.
> Then we can update the blk-rq-qos policy module w/o stopping the IO workload.
> And it is more convenient to introduce new policy on old machines w/o udgrade
> kernel. And we can close all of the blk-rq-qos policy if we needn't any of
> them. At the moment, the request_queue.rqos list is empty, we needn't to
> waste cpu cyles on them.
> 
>

Please write tests in blktests [1] to cover the code that we are
changing in this commit.

-ck

[1] https://github.com/osandov/blktests