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Date:   Tue, 21 Jan 2020 09:43:52 +0100
From:   Michal Hocko <mhocko@kernel.org>
To:     Wei Yang <richardw.yang@linux.intel.com>
Cc:     akpm@linux-foundation.org, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, yang.shi@linux.alibaba.com
Subject: Re: [PATCH 7/8] mm/migrate.c: move page on next iteration
Message-ID: <20200121084352.GE29276@dhcp22.suse.cz>
References: <20200119030636.11899-1-richardw.yang@linux.intel.com>
 <20200119030636.11899-8-richardw.yang@linux.intel.com>
 <20200120100203.GR18451@dhcp22.suse.cz>
 <20200121012200.GA1567@richard>
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On Tue 21-01-20 09:22:00, Wei Yang wrote:
> On Mon, Jan 20, 2020 at 11:02:03AM +0100, Michal Hocko wrote:
> >On Sun 19-01-20 11:06:35, Wei Yang wrote:
> >> When page is not successfully queued for migration, we would move pages
> >> on pagelist immediately. Actually, this could be done in the next
> >> iteration by telling it we need some help.
> >> 
> >> This patch adds a new variable need_move to be an indication. After
> >> this, we only need to call move_pages_and_store_status() twice.
> >
> >No! Not another iterator. There are two and this makes the function
> >quite hard to follow already. We do not want to add a third one.
> >
> 
> Two iterators here are? I don't get your point.

i is the main iterator to process the whole imput. start is another one
to control the batch to migrate. We do not need/want more. More clear?
-- 
Michal Hocko
SUSE Labs