Re: [PATCH v20 12/20] mm/vmscan: remove lruvec reget in move_pages_to_lru

[Johannes Weiner]

On Thu, Oct 29, 2020 at 06:44:57PM +0800, Alex Shi wrote:
> A isolated page shouldn't be recharged by memcg since the memcg
> migration isn't possible at the time.
> So remove unnecessary regetting.
> 
> Thanks to Alexander Duyck for pointing this out.
> 
> Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
> Acked-by: Hugh Dickins <hughd@xxxxxxxxxx>
> Cc: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
> Cc: Michal Hocko <mhocko@xxxxxxxxxx>
> Cc: Hugh Dickins <hughd@xxxxxxxxxx>
> Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
> Cc: linux-mm@xxxxxxxxx
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> Cc: cgroups@xxxxxxxxxxxxxxx

Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>

A brief comment in the code could be good: all pages were isolated
from the same lruvec (and isolation inhibits memcg migration).