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

[Roman Gushchin]

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 :)

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...