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Date: Thu, 19 Mar 2015 13:41:03 +0300
From: Vladimir Davydov <vdavydov@parallels.com>
To: Cyrill Gorcunov <gorcunov@gmail.com>
CC: Andrew Morton <akpm@linux-foundation.org>,
        Johannes Weiner <hannes@cmpxchg.org>, Michal Hocko <mhocko@suse.cz>,
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Subject: Re: [PATCH 3/3] mm: idle memory tracking
Message-ID: <20150319104103.GA12162@esperanza>
References: <cover.1426706637.git.vdavydov@parallels.com>
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 <20150319101205.GC27066@moon>
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On Thu, Mar 19, 2015 at 01:12:05PM +0300, Cyrill Gorcunov wrote:
> On Wed, Mar 18, 2015 at 11:44:36PM +0300, Vladimir Davydov wrote:
> > +static void set_mem_idle(void)
> > +{
> > +	int nid;
> > +
> > +	for_each_online_node(nid)
> > +		set_mem_idle_node(nid);
> > +}
> 
> Vladimir, might we need get_online_mems/put_online_mems here,
> or if node gets offline this wont be a problem? (Asking
> because i don't know).

I only need to dereference page structs corresponding to the node here,
and page structs are not freed when the node gets offline AFAICS, so I
guess it must be safe.

Thanks,
Vladimir