On 8/11/21 11:41 AM, Tejun Heo wrote:
> From e150c6478e453fe27b5cf83ed5d03b7582b6d35e Mon Sep 17 00:00:00 2001
> From: Tejun Heo <tj@xxxxxxxxxx>
> Date: Wed, 11 Aug 2021 07:29:20 -1000
>
> This reverts commit 08a9ad8bf607 ("block/mq-deadline: Add cgroup support")
> and a follow-up commit c06bc5a3fb42 ("block/mq-deadline: Remove a
> WARN_ON_ONCE() call"). The added cgroup support has the following issues:
>
> * It breaks cgroup interface file format rule by adding custom elements to a
> nested key-value file.
>
> * It registers mq-deadline as a cgroup-aware policy even though all it's
> doing is collecting per-cgroup stats. Even if we need these stats, this
> isn't the right way to add them.
>
> * It hasn't been reviewed from cgroup side.
I missed that the cgroup side hadn't seen or signed off on this one. I
have applied this revert for 5.14.
--
Jens Axboe
