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From:   Shakeel Butt <shakeelb@google.com>
Date:   Fri, 3 Jun 2022 17:47:14 -0700
Message-ID: <CALvZod6s8ss0Doe9y+X=3ZHvw0Ove9Lw3MdfKekXr0gVnJwA4w@mail.gmail.com>
Subject: Re: [PATCH] mm: memcontrol: separate {pgscan,pgsteal}_{kswapd,direct}
 items in memory.stat of cgroup v2
To:     Qi Zheng <zhengqi.arch@bytedance.com>
Cc:     Michal Hocko <mhocko@kernel.org>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Muchun Song <songmuchun@bytedance.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Jonathan Corbet <corbet@lwn.net>,
        Linux MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>,
        "open list:DOCUMENTATION" <linux-doc@vger.kernel.org>
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On Fri, Jun 3, 2022 at 12:06 AM Qi Zheng <zhengqi.arch@bytedance.com> wrote:
>
[...]
>
> diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
> index 176298f2f4de..0b9ca7e7df34 100644
> --- a/Documentation/admin-guide/cgroup-v2.rst
> +++ b/Documentation/admin-guide/cgroup-v2.rst
> @@ -1442,11 +1442,17 @@ PAGE_SIZE multiple when read back.
>           pgrefill (npn)
>                 Amount of scanned pages (in an active LRU list)
>
> -         pgscan (npn)
> -               Amount of scanned pages (in an inactive LRU list)
> +         pgscan_kswapd (npn)
> +               Amount of scanned pages by kswapd (in an inactive LRU list)
>
> -         pgsteal (npn)
> -               Amount of reclaimed pages
> +         pgscan_direct (npn)
> +               Amount of scanned pages directly  (in an inactive LRU list)
> +
> +         pgsteal_kswapd (npn)
> +               Amount of reclaimed pages by kswapd
> +
> +         pgsteal_direct (npn)
> +               Amount of reclaimed pages directly

No objection to adding new fields but removing 'pgsteal' and 'pgscan'
from the user visible API might break some applications.