Re: [PATCH v5 03/11] mm: memcontrol: prepare objcg API for non-kmem usage

[Muchun Song]

On Wed, Jun 01, 2022 at 11:33:46AM -0700, Roman Gushchin wrote:
> On Wed, Jun 01, 2022 at 07:34:34PM +0200, Michal Koutny wrote:
> > Hello.
> > 
> > On Mon, May 30, 2022 at 03:49:11PM +0800, Muchun Song <songmuchun@xxxxxxxxxxxxx> wrote:
> > > So we also allocate an object cgroup for the root_mem_cgroup.
> > 
> > This change made me wary that this patch also kmem charging in the
> > root_mem_cgroup. Fortunately, get_obj_cgroup_from_current won't return
> > this objcg so all is fine.
> 
> Yes, I had the same experience here :)
>

Sorry for the confusing.
 
> Overall I feel like the handling of the root memcg and objcg are begging
> for a cleanup, but it's really far from being trivial.
> 
> Maybe starting with documenting how it works now is a good idea...
> 

You mean add more comments into the commit log to explain the
usage of root memcg and root objcg?

Thanks.