Re: [PATCH block-5.14] Revert "block/mq-deadline: Add cgroup support"
From: Jens Axboe <axboe@kernel.dk>
Date: 2021-08-11 19:48:24
On 8/11/21 11:41 AM, Tejun Heo wrote:
From e150c6478e453fe27b5cf83ed5d03b7582b6d35e Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
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