On Wed, Oct 26, 2016 at 04:39:19PM +0530, Aneesh Kumar K.V wrote: > Jerome Glisse <j.gli...@gmail.com> writes: > > > On Tue, Oct 25, 2016 at 09:56:35AM +0530, Aneesh Kumar K.V wrote: > >> Jerome Glisse <j.gli...@gmail.com> writes: > >> > >> > On Mon, Oct 24, 2016 at 10:01:49AM +0530, Anshuman Khandual wrote: > >> > > >> I looked at the hmm-v13 w.r.t migration and I guess some form of device > >> callback/acceleration during migration is something we should definitely > >> have. I still haven't figured out how non addressable and coherent device > >> memory can fit together there. I was waiting for the page cache > >> migration support to be pushed to the repository before I start looking > >> at this closely. > >> > > > > The page cache migration does not touch the migrate code path. My issue with > > page cache is writeback. The only difference with existing migrate code is > > refcount check for ZONE_DEVICE page. Everything else is the same. > > What about the radix tree ? does file system migrate_page callback handle > replacing normal page with ZONE_DEVICE page/exceptional entries ? >
It use the exact same existing code (from mm/migrate.c) so yes the radix tree is updated and buffer_head are migrated. Jérôme
