On Thu 10-09-20 09:51:39, Laurent Dufour wrote: > Le 10/09/2020 à 09:23, Michal Hocko a écrit : > > On Wed 09-09-20 18:07:15, Laurent Dufour wrote: > > > Le 09/09/2020 à 12:59, Michal Hocko a écrit : > > > > On Wed 09-09-20 11:21:58, Laurent Dufour wrote: > > [...] > > > > > For the point a, using the enum allows to know in > > > > > register_mem_sect_under_node() if the link operation is due to a hotplug > > > > > operation or done at boot time. > > > > > > > > Yes, but let me repeat. We have a mess here and different paths check > > > > for the very same condition by different ways. We need to unify those. > > > > > > What are you suggesting to unify these checks (using a MP_* enum as > > > suggested by David, something else)? > > > > We do have system_state check spread at different places. I would use > > this one and wrap it behind a helper. Or have I missed any reason why > > that wouldn't work for this case? > > That would not work in that case because memory can be hot-added at the > SYSTEM_SCHEDULING system state and the regular memory is also registered at > that system state too. So system state is not enough to discriminate between > the both. If that is really the case all other places need a fix as well. Btw. could you be more specific about memory hotplug during early boot? How that happens? I am only aware of https://lkml.kernel.org/r/20200818110046.6664-1-osalvador@xxxxxxx and that doesn't happen as early as SYSTEM_SCHEDULING. -- Michal Hocko SUSE Labs
