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Date:   Thu, 29 Oct 2020 09:43:46 -0400
From:   Johannes Weiner <hannes@cmpxchg.org>
To:     Alex Shi <alex.shi@linux.alibaba.com>
Cc:     akpm@linux-foundation.org, mgorman@techsingularity.net,
        tj@kernel.org, hughd@google.com, khlebnikov@yandex-team.ru,
        daniel.m.jordan@oracle.com, willy@infradead.org, lkp@intel.com,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        cgroups@vger.kernel.org, shakeelb@google.com,
        iamjoonsoo.kim@lge.com, richard.weiyang@gmail.com,
        kirill@shutemov.name, alexander.duyck@gmail.com,
        rong.a.chen@intel.com, mhocko@suse.com, vdavydov.dev@gmail.com,
        shy828301@gmail.com, Michal Hocko <mhocko@kernel.org>
Subject: Re: [PATCH v20 01/20] mm/memcg: warning on !memcg after readahead
 page charged
Message-ID: <20201029134346.GB599825@cmpxchg.org>
References: <1603968305-8026-1-git-send-email-alex.shi@linux.alibaba.com>
 <1603968305-8026-2-git-send-email-alex.shi@linux.alibaba.com>
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On Thu, Oct 29, 2020 at 06:44:46PM +0800, Alex Shi wrote:
> Add VM_WARN_ON_ONCE_PAGE() macro.
> 
> Since readahead page is charged on memcg too, in theory we don't have to
> check this exception now. Before safely remove them all, add a warning
> for the unexpected !memcg.
> 
> Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
> Acked-by: Michal Hocko <mhocko@suse.com>
> Acked-by: Hugh Dickins <hughd@google.com>
> Cc: Johannes Weiner <hannes@cmpxchg.org>
> Cc: Michal Hocko <mhocko@kernel.org>
> Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>
> Cc: cgroups@vger.kernel.org
> Cc: linux-mm@kvack.org
> Cc: linux-kernel@vger.kernel.org

Acked-by: Johannes Weiner <hannes@cmpxchg.org>