The virtio_blk guest driver has supported multiple virtqueues since Linux 3.17. This patch series adds multiple virtqueues to QEMU's virtio-blk emulated device.
Ming Lei sent patches previously but these were not merged. This series implements virtio-blk multiqueue for QEMU from scratch since the codebase has changed. Live migration support for s->rq was also missing from the previous series and has been added. It's important to note that QEMU's block layer does not support multiqueue yet. Therefore virtio-blk device processes all virtqueues in the same AioContext (IOThread). Further work is necessary to take advantage of multiqueue support in QEMU's block layer once it becomes available. I will post performance results once they are ready. Stefan Hajnoczi (9): virtio-blk: use batch notify in non-dataplane case virtio-blk: tell dataplane which vq to notify virtio-blk: associate request with a virtqueue virtio-blk: add VirtIOBlockConf->num_queues virtio-blk: multiqueue batch notify vmstate: add VMSTATE_VARRAY_UINT32_ALLOC virtio-blk: live migrate s->rq with multiqueue virtio-blk: dataplane multiqueue support virtio-blk: add num-queues device property hw/block/dataplane/virtio-blk.c | 68 +++++++------- hw/block/dataplane/virtio-blk.h | 2 +- hw/block/virtio-blk.c | 200 ++++++++++++++++++++++++++++++++++++---- include/hw/virtio/virtio-blk.h | 13 ++- include/migration/vmstate.h | 10 ++ 5 files changed, 241 insertions(+), 52 deletions(-) -- 2.5.5
