On Thu, Jul 19, 2018 at 10:03 AM Michal Hocko <mhocko@xxxxxxxxxx> wrote: > > On Thu 19-07-18 15:58:59, Oscar Salvador wrote: > > On Thu, Jul 19, 2018 at 03:46:22PM +0200, Michal Hocko wrote: > > > On Thu 19-07-18 15:27:40, osalvador@xxxxxxxxxxxxxxxxxx wrote: > > > > From: Oscar Salvador <osalvador@xxxxxxx> > > > > > > > > We should only care about deferred initialization when booting. > > > > > > Again why is this worth doing? > > > > Well, it is not a big win if that is what you meant. > > > > Those two fields are only being used when dealing with deferred pages, > > which only happens at boot time. > > > > If later on, free_area_init_node gets called from memhotplug code, > > we will also set the fields, although they will not be used. > > > > Is this a problem? No, but I think it is more clear from the code if we > > see when this is called. > > So I would say it was only for code consistency. > > Then put it to the changelog. > > > If you think this this is not worth, I am ok with dropping it. > > I am not really sure. I am not a big fan of SYSTEM_BOOTING global > thingy so I would rather not spread its usage. I agree, I do not think this patch is necessary. Calling pgdat_set_deferred_range() does not hurt in hotplug context, and it is cheap too. SYSTEM_BOOTING sometimes useful, but it is better to use it only where necessary, where without this "if" we will encounter some bugs. Thank you, Pavel
