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Date:   Mon, 13 Jan 2020 10:36:14 +0300
From:   "Kirill A. Shutemov" <kirill@shutemov.name>
To:     Wei Yang <richardw.yang@linux.intel.com>
Cc:     hannes@cmpxchg.org, mhocko@kernel.org, vdavydov.dev@gmail.com,
        akpm@linux-foundation.org, cgroups@vger.kernel.org,
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        kirill.shutemov@linux.intel.com, yang.shi@linux.alibaba.com,
        alexander.duyck@gmail.com, rientjes@google.com
Subject: Re: [Patch v2] mm: thp: grab the lock before manipulation defer list
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On Mon, Jan 13, 2020 at 08:44:57AM +0800, Wei Yang wrote:
> >> It is possible two page in the same pgdate or memcg grab page lock
> >> respectively and then access the same defer queue concurrently.
> 
> If my understanding is correct, you agree with my statement?

Which one? If the one above then no. list_empty only accesses list_head
for the struct page, not the queue.

-- 
 Kirill A. Shutemov