Re: [External] [PATCH 1/2] mm: memcg: fix memcg file_dirty numa stat

[Muchun Song]

On Mon, Dec 28, 2020 at 2:13 AM Shakeel Butt <shakeelb@xxxxxxxxxx> wrote:
>
> The kernel updates the per-node NR_FILE_DIRTY stats on page migration
> but not the memcg numa stats. That was not an issue until recently the
> commit 5f9a4f4a7096 ("mm: memcontrol: add the missing numa_stat interface
> for cgroup v2") exposed numa stats for the memcg. So fixing the
> file_dirty per-memcg numa stat.
>
> Fixes: 5f9a4f4a7096 ("mm: memcontrol: add the missing numa_stat interface for cgroup v2")

Thanks for catching this problem.

Reviewed-by: Muchun Song <songmuchun@xxxxxxxxxxxxx>

> Signed-off-by: Shakeel Butt <shakeelb@xxxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx>
> ---
>  mm/migrate.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/mm/migrate.c b/mm/migrate.c
> index ee5e612b4cd8..613794f6a433 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -500,9 +500,9 @@ int migrate_page_move_mapping(struct address_space *mapping,
>                         __inc_lruvec_state(new_lruvec, NR_SHMEM);
>                 }
>                 if (dirty && mapping_can_writeback(mapping)) {
> -                       __dec_node_state(oldzone->zone_pgdat, NR_FILE_DIRTY);
> +                       __dec_lruvec_state(old_lruvec, NR_FILE_DIRTY);
>                         __dec_zone_state(oldzone, NR_ZONE_WRITE_PENDING);
> -                       __inc_node_state(newzone->zone_pgdat, NR_FILE_DIRTY);
> +                       __inc_lruvec_state(new_lruvec, NR_FILE_DIRTY);
>                         __inc_zone_state(newzone, NR_ZONE_WRITE_PENDING);
>                 }
>         }
> --
> 2.29.2.729.g45daf8777d-goog
>


--
Yours,
Muchun