Received-SPF: pass (google.com: domain of linux-ext4-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
Date:   Wed, 8 Jun 2022 20:56:16 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net,
        linux-mm@kvack.org, linux-nilfs@vger.kernel.org
Subject: Re: [PATCH 08/10] vmscan: Add check_move_unevictable_folios()
Message-ID: <YqFvYAlGGWW7ohTZ@infradead.org>
References: <20220605193854.2371230-1-willy@infradead.org>
 <20220605193854.2371230-9-willy@infradead.org>
 <YqBYxNPu3tLiN5kI@infradead.org>
 <YqDPIv5IgNHK/pJT@casper.infradead.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <YqDPIv5IgNHK/pJT@casper.infradead.org>
Precedence: bulk

On Wed, Jun 08, 2022 at 05:32:34PM +0100, Matthew Wilcox wrote:
> On Wed, Jun 08, 2022 at 01:07:32AM -0700, Christoph Hellwig wrote:
> > On Sun, Jun 05, 2022 at 08:38:52PM +0100, Matthew Wilcox (Oracle) wrote:
> > > Change the guts of check_move_unevictable_pages() over to use folios
> > > and add check_move_unevictable_pages() as a wrapper.
> > 
> > The changes here look fine, but please also add patches for converting
> > the two callers (which looks mostly trivial to me).
> 
> I do want to get rid of pagevecs entirely, but that conversion isn't
> going to happen in time for the next merge window.  for_each_sgt_page()
> is a little intimidating.

for_each_sgt_page, just like other creative scatterlist abuse in the gpu
code is a beast.  But, instead of doing a for_each_sgt_page to add
pages to the pagevec and then do a loop over the pagevec to add to
the folio batch it should be pretty trivial to just cut out the
middle man.