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Date:   Fri, 7 Jun 2019 16:25:25 +0200
From:   Michal Hocko <mhocko@kernel.org>
To:     Hugh Dickins <hughd@google.com>
Cc:     Yang Shi <yang.shi@linux.alibaba.com>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        vbabka@suse.cz, rientjes@google.com, kirill@shutemov.name,
        akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org
Subject: Re: [v2 PATCH] mm: thp: fix false negative of shmem vma's THP
 eligibility
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On Fri 07-06-19 03:57:18, Hugh Dickins wrote:
[...]
> The addition of "THPeligible" without an "Anon" in its name was
> unfortunate. I suppose we're two releases too late to change that.

Well, I do not really see any reason why THPeligible should be Anon
specific at all. Even if ...

> Applying process (PR_SET_THP_DISABLE) and mm (MADV_*HUGEPAGE)
> limitations to shared filesystem objects doesn't work all that well.

... this is what we are going with then it is really important to have a
single place to query the eligibility IMHO.

> I recommend that you continue to treat shmem objects separately from
> anon memory, and just make the smaps "THPeligible" more often accurate.

Agreed on this.

-- 
Michal Hocko
SUSE Labs