Re: [PATCH v3 28/30 fix 1/2] mm: memcontrol: fix lruvec_stats->state_local reparenting

[Qi Zheng]

On 1/21/26 2:47 AM, Shakeel Butt wrote:
> On Tue, Jan 20, 2026 at 03:19:00PM +0800, Muchun Song wrote:
> > > > No reparenting local stats for v2.
> > >
> > > It seems that lruvec_stats->state_local (non-hierarchical) needs to be
> > > relocated in both v1 and v2.
> >
> > Here we might need to elaborate a bit. Specifically, in the function
> > `count_shadow_nodes`, the use of `lruvec_page_state_local` to obtain
> > LRU and SLAB pages seems to also require these logics to work correctly.
> > For SLAB, it appears that the statistics here have already been
> > problematic for a while since SLAB pages have been reparented, right?
>
> Thanks a lot, now it is clear and yes it seems like SLAB is problematic
> but now I am wondering if it is really worth fixing. For LRU pages, how
> about using lruvec_lru_size() defined in vmscan.c. That would at least
> keep count_shadow_nodes() working irrespective of LRU reparenting.

Do you mean calling lruvec_lru_size() in count_shadow_nodes()? But
numa_stat interface also reads lruvec_stats->state and make it visible
to the user.

>