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

On 2022/2/15 9:01 下午, Chaitanya Kulkarni wrote:

Wang Jianchao (Kuaishou),

On 2/15/22 04:36, Wang Jianchao (Kuaishou) wrote:

quoted

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

Yes, I will send out next

Thanks
Jianchao