On Thu 19-09-19 16:22:27, David Hildenbrand wrote: > virtio-mem wants to offline and remove a memory block once it unplugged > all subblocks (e.g., using alloc_contig_range()). Let's provide > an interface to do that from a driver. virtio-mem already supports to > offline partially unplugged memory blocks. Offlining a fully unplugged > memory block will not require to migrate any pages. All unplugged > subblocks are PageOffline() and have a reference count of 0 - so > offlining code will simply skip them. > > All we need an interface to trigger the "offlining" and the removing in a > single operation - to make sure the memory block cannot get onlined by > user space again before it gets removed. > > To keep things simple, allow to only work on a single memory block. Without a user it is not really clear why do we need this interface. I am also not really sure why do you want/need to control beyond the offlining stage. Care to explain some more? -- Michal Hocko SUSE Labs
