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Date:   Mon, 15 Mar 2021 13:45:08 +0000
From:   Matthew Wilcox <willy@infradead.org>
To:     "Kirill A. Shutemov" <kirill@shutemov.name>
Cc:     Hugh Dickins <hughd@google.com>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v4 00/25] Page folios
Message-ID: <20210315134508.GX2577561@casper.infradead.org>
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On Mon, Mar 15, 2021 at 02:55:01PM +0300, Kirill A. Shutemov wrote:
> I'm with Matthew on this. I would really want to drop the number of places
> where we call compoud_head(). I hope we can get rid of the page flag
> policy hack I made.

I can't see that far ahead too clearly, but I do think that at some
point we'll actually distinguish between folio flags and page flags.
For example, we won't have a FolioHWPoison, because we won't keep a folio
together if one page in it has become defective.  Nor will we have a
PageUptodate because we'll only care about whether a folio is uptodate.
And at that point, we won't want page flag policies.