lkml.org 
[lkml]   [2021]   [Apr]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCH 1/7] mm: memcontrol: fix page charging in page replacement
    On Tue 13-04-21 14:51:47, Muchun Song wrote:
    > The pages aren't accounted at the root level, so do not charge the page
    > to the root memcg in page replacement. Although we do not display the
    > value (mem_cgroup_usage) so there shouldn't be any actual problem, but
    > there is a WARN_ON_ONCE in the page_counter_cancel(). Who knows if it
    > will trigger? So it is better to fix it.
    >
    > Signed-off-by: Muchun Song <songmuchun@bytedance.com>
    > Acked-by: Johannes Weiner <hannes@cmpxchg.org>
    > Reviewed-by: Shakeel Butt <shakeelb@google.com>

    Acked-by: Michal Hocko <mhocko@suse.com>

    > ---
    > mm/memcontrol.c | 8 +++++---
    > 1 file changed, 5 insertions(+), 3 deletions(-)
    >
    > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
    > index 64ada9e650a5..f229de925aa5 100644
    > --- a/mm/memcontrol.c
    > +++ b/mm/memcontrol.c
    > @@ -6806,9 +6806,11 @@ void mem_cgroup_migrate(struct page *oldpage, struct page *newpage)
    > /* Force-charge the new page. The old one will be freed soon */
    > nr_pages = thp_nr_pages(newpage);
    >
    > - page_counter_charge(&memcg->memory, nr_pages);
    > - if (do_memsw_account())
    > - page_counter_charge(&memcg->memsw, nr_pages);
    > + if (!mem_cgroup_is_root(memcg)) {
    > + page_counter_charge(&memcg->memory, nr_pages);
    > + if (do_memsw_account())
    > + page_counter_charge(&memcg->memsw, nr_pages);
    > + }
    >
    > css_get(&memcg->css);
    > commit_charge(newpage, memcg);
    > --
    > 2.11.0

    --
    Michal Hocko
    SUSE Labs

    \
     
     \ /
      Last update: 2021-04-14 11:21    [W:3.565 / U:0.232 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site