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Date:   Wed, 31 Jan 2018 08:58:52 +0100
From:   Michal Hocko <mhocko@kernel.org>
To:     Anshuman Khandual <khandual@linux.vnet.ibm.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        akpm@linux-foundation.org
Subject: Re: [RFC] mm/migrate: Add new migration reason MR_HUGETLB
Message-ID: <20180131075852.GL21609@dhcp22.suse.cz>
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On Wed 31-01-18 07:55:05, Anshuman Khandual wrote:
> On 01/30/2018 01:29 PM, Michal Hocko wrote:
> > On Tue 30-01-18 08:37:14, Anshuman Khandual wrote:
> >> alloc_contig_range() initiates compaction and eventual migration for
> >> the purpose of either CMA or HugeTLB allocation. At present, reason
> >> code remains the same MR_CMA for either of those cases. Lets add a
> >> new reason code which will differentiate the purpose of migration
> >> as HugeTLB allocation instead.
> > Why do we need it?
> 
> The same reason why we have MR_CMA (maybe some other ones as well) at
> present, for reporting purpose through traces at the least. It just
> seemed like same reason code is being used for two different purpose
> of migration.

But do we have any real user asking for this kind of information?

-- 
Michal Hocko
SUSE Labs