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Date:   Wed, 14 Aug 2019 10:19:50 +0800
From:   Wei Yang <richardw.yang@linux.intel.com>
To:     Matthew Wilcox <willy@infradead.org>
Cc:     Wei Yang <richardw.yang@linux.intel.com>,
        akpm@linux-foundation.org, mgorman@techsingularity.net,
        vbabka@suse.cz, linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm/mmap.c: rb_parent is not necessary in __vma_link_list
Message-ID: <20190814021950.GA2025@richard>
Reply-To: Wei Yang <richardw.yang@linux.intel.com>
References: <20190813032656.16625-1-richardw.yang@linux.intel.com>
 <20190813033958.GB5307@bombadil.infradead.org>
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On Mon, Aug 12, 2019 at 08:39:58PM -0700, Matthew Wilcox wrote:
>On Tue, Aug 13, 2019 at 11:26:56AM +0800, Wei Yang wrote:
>> Now we use rb_parent to get next, while this is not necessary.
>> 
>> When prev is NULL, this means vma should be the first element in the
>> list. Then next should be current first one (mm->mmap), no matter
>> whether we have parent or not.
>> 
>> After removing it, the code shows the beauty of symmetry.
>
>Uhh ... did you test this?
>

I have enabled DEBUG_VM_RB, system looks good with this.

-- 
Wei Yang
Help you, Help me