On Wed, Apr 03, 2019 at 10:37:57AM +0200, Michal Hocko wrote: > That being said it should be the caller of the hotplug code to tell > the vmemmap allocation strategy. For starter, I would only pack vmemmaps > for "regular" kernel zone memory. Movable zones should be more careful. > We can always re-evaluate later when there is a strong demand for huge > pages on movable zones but this is not the case now because those pages > are not really movable in practice. I agree that makes sense to let the caller specify if it wants to allocate vmemmaps per memblock or per memory-range, so we are more flexible when it comes to granularity in hot-add/hot-remove operations. But the thing is that the zones are picked at onling stage, while vmemmaps are created at hot-add stage, so I am not sure we can define the strategy depending on the zone. -- Oscar Salvador SUSE L3
