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Date:   Tue, 20 Aug 2019 10:26:29 -0700
From:   Matthew Wilcox <willy@infradead.org>
To:     Vlastimil Babka <vbabka@suse.cz>
Cc:     Wei Yang <richardw.yang@linux.intel.com>,
        Christoph Hellwig <hch@infradead.org>,
        akpm@linux-foundation.org, mgorman@techsingularity.net,
        osalvador@suse.de, linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/3] mm/mmap.c: extract __vma_unlink_list as counter part
 for __vma_link_list
Message-ID: <20190820172629.GB4949@bombadil.infradead.org>
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 <20190814051611.GA1958@infradead.org>
 <20190814065703.GA6433@richard>
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On Wed, Aug 14, 2019 at 11:19:37AM +0200, Vlastimil Babka wrote:
> On 8/14/19 8:57 AM, Wei Yang wrote:
> > On Tue, Aug 13, 2019 at 10:16:11PM -0700, Christoph Hellwig wrote:
> >>Btw, is there any good reason we don't use a list_head for vma linkage?
> > 
> > Not sure, maybe there is some historical reason?
> 
> Seems it was single-linked until 2010 commit 297c5eee3724 ("mm: make the vma
> list be doubly linked") and I guess it was just simpler to add the vm_prev link.
> 
> Conversion to list_head might be an interesting project for some "advanced
> beginner" in the kernel :)

I'm working to get rid of vm_prev and vm_next, so it would probably be
wasted effort.