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Date:   Mon, 25 Apr 2022 13:30:09 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     David Howells <dhowells@redhat.com>
Cc:     linux-cachefs@redhat.com,
        Rohith Surabattula <rohiths.msft@gmail.com>,
        Steve French <sfrench@samba.org>,
        Shyam Prasad N <nspmangalore@gmail.com>,
        linux-cifs@vger.kernel.org, Jeff Layton <jlayton@redhat.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [PATCH 14/14] mm, netfs, fscache: Stop read optimisation when
 folio removed from pagecache
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On Mon, Apr 25, 2022 at 01:07:41PM +0100, David Howells wrote:
> Matthew Wilcox <willy@infradead.org> wrote:
> 
> > OK.  You suggested that releasepage was an acceptable place to call it.
> > How about we have AS_RELEASE_ALL (... or something ...) and then
> > page_has_private() becomes a bit more complicated ... to the point
> > where we should probably get rid of it (by embedding it into
> > filemap_release_folio():
> 
> I'm not sure page_has_private() is quite so easy to get rid of.
> shrink_page_list() and collapse_file(), for example, use it to conditionalise
> a call to try_to_release_page() plus some other bits.

That's what I was saying.  Make the calls to try_to_release_page()
unconditional and delete page_has_private() because it only confuses
people who should actually be using PagePrivate().

> I think that, for the moment, I would need to add a check for AS_RELEASE_ALL
> to page_has_private().
> 
> David
> 
>