On Mon, Oct 12, 2020 at 02:52:54PM +0200, David Hildenbrand wrote: > virtio-mem currently only supports device block sizes that span at most > a single Linux memory block. For example, gigantic pages in the hypervisor > result on x86-64 in a device block size of 1 GiB - when the Linux memory > block size is 128 MiB, we cannot support such devices (we fail loading the > driver). Of course, we want to support any device block size in any Linux > VM. > > Bigger device block sizes will become especially important once supporting > VFIO in QEMU - each device block has to be mapped separately, and the > maximum number of mappings for VFIO is 64k. So we usually want blocks in > the gigabyte range when wanting to grow the VM big. I guess it missed this Linux right? There's an mm change which did not get an ack from mm mainatiners, so I can't merge it ... > This series: > - Performs some cleanups > - Factors out existing Sub Block Mode (SBM) > - Implements memory hot(un)plug in Big Block Mode (BBM) > > I need one core-mm change, to make offline_and_remove_memory() eat bigger > chunks. > > This series is based on "next-20201009" and can be found at: > git@xxxxxxxxxx:virtio-mem/linux.git virtio-mem-dbm-v1 > > Once some virtio-mem patches that are pending in the -mm tree are upstream > (I guess they'll go in in 5.10), I'll resend based on Linus' tree. > I suggest to take this (including the MM patch, acks/review please) via the > vhost tree once time has come. In the meantime, I'll do more testing. > > David Hildenbrand (29): > virtio-mem: determine nid only once using memory_add_physaddr_to_nid() > virtio-mem: simplify calculation in > virtio_mem_mb_state_prepare_next_mb() > virtio-mem: simplify MAX_ORDER - 1 / pageblock_order handling > virtio-mem: drop rc2 in virtio_mem_mb_plug_and_add() > virtio-mem: generalize check for added memory > virtio-mem: generalize virtio_mem_owned_mb() > virtio-mem: generalize virtio_mem_overlaps_range() > virtio-mem: drop last_mb_id > virtio-mem: don't always trigger the workqueue when offlining memory > virtio-mem: generalize handling when memory is getting onlined > deferred > virtio-mem: use "unsigned long" for nr_pages when fake > onlining/offlining > virtio-mem: factor out fake-offlining into virtio_mem_fake_offline() > virtio-mem: factor out handling of fake-offline pages in memory > notifier > virtio-mem: retry fake-offlining via alloc_contig_range() on > ZONE_MOVABLE > virito-mem: document Sub Block Mode (SBM) > virtio-mem: memory block states are specific to Sub Block Mode (SBM) > virito-mem: subblock states are specific to Sub Block Mode (SBM) > virtio-mem: factor out calculation of the bit number within the > sb_states bitmap > virito-mem: existing (un)plug functions are specific to Sub Block Mode > (SBM) > virtio-mem: nb_sb_per_mb and subblock_size are specific to Sub Block > Mode (SBM) > virtio-mem: memory notifier callbacks are specific to Sub Block Mode > (SBM) > virtio-mem: memory block ids are specific to Sub Block Mode (SBM) > virtio-mem: factor out adding/removing memory from Linux > virtio-mem: print debug messages from virtio_mem_send_*_request() > virtio-mem: Big Block Mode (BBM) memory hotplug > virtio-mem: allow to force Big Block Mode (BBM) and set the big block > size > mm/memory_hotplug: extend offline_and_remove_memory() to handle more > than one memory block > virtio-mem: Big Block Mode (BBM) - basic memory hotunplug > virtio-mem: Big Block Mode (BBM) - safe memory hotunplug > > drivers/virtio/virtio_mem.c | 1783 +++++++++++++++++++++++++---------- > mm/memory_hotplug.c | 105 ++- > 2 files changed, 1373 insertions(+), 515 deletions(-) > > -- > 2.26.2
