Re: [PATCH v2 3/3] mm/memcg: introduce mem_cgroup_early_init

[Shakeel Butt]

On Thu, Apr 24, 2025 at 09:00:01AM -0700, Shakeel Butt wrote:
> On Thu, Apr 24, 2025 at 08:09:29PM +0800, Huan Yang wrote:
> > When cgroup_init() creates root_mem_cgroup through css_online callback,
> > some critical resources might not be fully initialized, forcing later
> > operations to perform conditional checks for resource availability.
> > 
> > This patch introduces mem_cgroup_early_init() to address the init order,
> > it invoke before cgroup_init, so, compare mem_cgroup_init which invoked
> > by initcall, mem_cgroup_early_init can use to prepare some key resources
> > before root_mem_cgroup alloc.
> > 
> > Signed-off-by: Huan Yang <link@xxxxxxxx>
> > Suggested-by: Shakeel Butt <shakeel.butt@xxxxxxxxx>
> 
> Please move this patch as the first patch of the series and also remove
> the "early" from the function name as it has a different meaning in the
> context of cgroup init. Something like either memcg_init() or
> memcg_kmem_caches_init().

BTW I think just putting this kmem cache creation in mem_cgroup_init()
and explicitly calling it before cgroup_init() would be fine. In that
case there would be a single memcg init function.