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Date:   Wed, 13 Jan 2021 10:43:02 -0800
From:   Roman Gushchin <guro@fb.com>
To:     Shakeel Butt <shakeelb@google.com>
CC:     Arjun Roy <arjunroy@google.com>,
        Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@kernel.org>,
        Eric Dumazet <edumazet@google.com>,
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        Jakub Kicinski <kuba@kernel.org>,
        Linux MM <linux-mm@kvack.org>,
        Cgroups <cgroups@vger.kernel.org>,
        netdev <netdev@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] mm: net: memcg accounting for TCP rx zerocopy
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On Tue, Jan 12, 2021 at 04:18:44PM -0800, Shakeel Butt wrote:
> On Tue, Jan 12, 2021 at 4:12 PM Arjun Roy <arjunroy@google.com> wrote:
> >
> > On Tue, Jan 12, 2021 at 3:48 PM Roman Gushchin <guro@fb.com> wrote:
> > >
> [snip]
> > > Historically we have a corresponding vmstat counter to each charged page.
> > > It helps with finding accounting/stastistics issues: we can check that
> > > memory.current ~= anon + file + sock + slab + percpu + stack.
> > > It would be nice to preserve such ability.
> > >
> >
> > Perhaps one option would be to have it count as a file page, or have a
> > new category.
> >
> 
> Oh these are actually already accounted for in NR_FILE_MAPPED.

Well, it's confusing. Can't we fix this by looking at the new page memcg flag?