Re: [PATCH -next] blk-cgroup: move congestion_count to struct blkcg

From: Tejun Heo
Date: Sat Jul 13 2024 - 13:35:42 EST


Hello,

On Sat, Jul 13, 2024 at 06:56:57PM +0800, Yu Kuai wrote:
> 在 2024/07/13 1:19, Tejun Heo 写道:
> > Hello,
> >
> > On Fri, Jul 12, 2024 at 08:51:41AM +0000, Xiu Jianfeng wrote:
> > > The congestion_count was introduced by commit d09d8df3a294 ("blkcg:
> > > add generic throttling mechanism"), but since it is closely related
> > > to the blkio subsys, it is not appropriate to put it in the struct
> > > cgroup, so move it to struct blkcg.
> > >
> > > Signed-off-by: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx>
> > > ---
> > > only compiling tested
> >
> > blkcg is per cgroup and blkg is per cgroup-device pair, so the change isn't
> > just moving the field but updating what it means and how it works. The
> > change needs a lot more thinking, justification and testing
> I understand blkcg and blkg, however, maybe I'm being noob, I don't see
> how this patch is related to blkg, the change is that 'congestion_count'
> is moved from cgroup to blkcg. This look quite straightforward to me,
> maybe I'm missing something, can you explain more?

Oh, my apologies. That was me confidently misreading the patch. Sorry about
that. I'll re-read the patch.

Thanks.

--
tejun