On Mon, Apr 20, 2020 at 06:11:17PM -0400, Johannes Weiner wrote: > Memcg maintains private MEMCG_CACHE and NR_SHMEM counters. This > divergence from the generic VM accounting means unnecessary code > overhead, and creates a dependency for memcg that page->mapping is set > up at the time of charging, so that page types can be told apart. > > Convert the generic accounting sites to mod_lruvec_page_state and > friends to maintain the per-cgroup vmstat counters of NR_FILE_PAGES > and NR_SHMEM. The page is already locked in these places, so > page->mem_cgroup is stable; we only need minimal tweaks of two > mem_cgroup_migrate() calls to ensure it's set up in time. > > Then replace MEMCG_CACHE with NR_FILE_PAGES and delete the private > NR_SHMEM accounting sites. > > Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx> Reviewed-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
