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? >-- >Michal Hocko >SUSE Labs -- Wei Yang Help you, Help me
