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From: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
To: Anshuman Khandual <khandual@linux.vnet.ibm.com>
CC: "linux-mm@kvack.org" <linux-mm@kvack.org>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
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        Balbir Singh <bsingharora@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Naoya Horiguchi" <nao.horiguchi@gmail.com>
Subject: Re: [PATCH v2 07/12] mm: thp: check pmd migration entry in common
 path
Thread-Topic: [PATCH v2 07/12] mm: thp: check pmd migration entry in common
 path
Thread-Index: AQHSOVF91G9mSKw0IEiSF7PKRh5xwqDRUXsAgAAKB4A=
Date: Thu, 10 Nov 2016 09:12:07 +0000
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On Thu, Nov 10, 2016 at 02:06:14PM +0530, Anshuman Khandual wrote:
> On 11/08/2016 05:01 AM, Naoya Horiguchi wrote:
> > If one of callers of page migration starts to handle thp, memory management code
> > start to see pmd migration entry, so we need to prepare for it before enabling.
> > This patch changes various code point which checks the status of given pmds in
> > order to prevent race between thp migration and the pmd-related works.
> 
> There are lot of changes in this one patch. Should not we split
> this up into multiple patches and explain them in a bit detail
> through their commit messages ?

Yes, and I admit that I might change more than necessary, if the context
never encounters migration entry for any reason, no change is needed.
I'll dig more detail.

- Naoya Horiguchi