On Mon 19-11-18 21:44:50, Wei Yang wrote: > On Mon, Nov 19, 2018 at 03:23:25PM +0100, Michal Hocko wrote: > >On Mon 19-11-18 14:15:05, Wei Yang wrote: > >> On Mon, Nov 19, 2018 at 11:07:41AM +0100, osalvador wrote: > >> > > >> >> Signed-off-by: Wei Yang <richard.weiyang@xxxxxxxxx> > >> > > >> >Good catch. > >> > > >> >One thing I was wondering is that if we also should re-adjust it when a > >> >zone gets emptied during offlining memory. > >> >I checked, and whenever we work wirh pgdat->nr_zones we seem to check > >> >if the zone is populated in order to work with it. > >> >But still, I wonder if we should re-adjust it. > >> > >> Well, thanks all for comments. I am glad you like it. > >> > >> Actually, I have another proposal or I notice another potential issue. > >> > >> In case user online pages in parallel, we may face a contention and get > >> a wrong nr_zones. > > > >No, this should be protected by the global mem hotplug lock. Anyway a > >dedicated lock would be much better. I would move it under > >pgdat_resize_lock. > > This is what I think about. > > Do you like me to send v2 with this change? Or you would like to add it > by yourself? This is independent on this patch. So feel free to send a separate patch. -- Michal Hocko SUSE Labs
