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Date:   Mon, 13 Jan 2020 16:23:08 +0800
From:   Wei Yang <richardw.yang@linux.intel.com>
To:     "Kirill A. Shutemov" <kirill@shutemov.name>
Cc:     Wei Yang <richardw.yang@linux.intel.com>, hannes@cmpxchg.org,
        mhocko@kernel.org, vdavydov.dev@gmail.com,
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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
Message-ID: <20200113082308.GB27972@richard>
Reply-To: Wei Yang <richardw.yang@linux.intel.com>
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On Mon, Jan 13, 2020 at 10:36:14AM +0300, Kirill A. Shutemov wrote:
>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.
>

Ah, I get your point.

>-- 
> Kirill A. Shutemov

-- 
Wei Yang
Help you, Help me