[Qemu-devel] [PATCH v4 0/6] Add netmap backend offloadings support

[Vincenzo Maffione <v.maffione@gmail.com>]

The purpose of this patch series is to add offloadings support
(TSO/UFO/CSUM) to the netmap network backend, and make it possible
for the paravirtual network frontends (virtio-net and vmxnet3) to
use it.
In order to achieve this, these patches extend the existing
net.h interface to add abstract operations through which a network
frontend can manipulate backend offloading features, instead of
directly calling TAP-specific functions.

Guest-to-guest performance before this patches for virtio-net + netmap:

    TCP_STREAM                  5.0 Gbps
    TCP_RR                      12.7 Gbps
    UDP_STREAM (64-bytes)       790 Kpps

Guest-to-guest performance after this patches for virtio-net + netmap:

    TCP_STREAM                  21.4 Gbps
    TCP_RR                      12.7 Gbps
    UDP_STREAM (64-bytes)       790 Kpps

Experiment details:
    - Processor: Intel i7-3770K CPU @ 3.50GHz (8 cores)
    - Memory @ 1333 MHz
    - Host O.S.: Archlinux with Linux 3.11
    - Guest O.S.: Archlinux with Linux 3.11

    - QEMU command line:
        qemu-system-x86_64 archdisk.qcow -snapshot -enable-kvm -device virtio-net-pci,ioeventfd=on,mac=00:AA:BB:CC:DD:01,netdev=mynet -netdev netmap,ifname=vale0:01,id=mynet -smp 2 -vga std -m 3G


******** Changes against the previous version ***********
  (1) make tap offloading callbacks static
  (2) tap-win32.c modified to initialize offloading callback pointers
  (3) fix a bug when calling qemu_peer_using_vnet_header

Vincenzo Maffione (6):
  net: change vnet-hdr TAP prototypes
  net: extend NetClientInfo for offloading
  net: TAP uses NetClientInfo offloading callbacks
  net: virtio-net and vmxnet3 use offloading API
  net: make tap offloading callbacks static
  net: add offloading support to netmap backend

 hw/net/vhost_net.c  |  4 +--
 hw/net/virtio-net.c | 16 ++++------
 hw/net/vmxnet3.c    | 12 +++----
 include/net/net.h   | 19 +++++++++++
 include/net/tap.h   |  6 ----
 net/net.c           | 55 ++++++++++++++++++++++++++++++++
 net/netmap.c        | 68 ++++++++++++++++++++++++++++++++++++++-
 net/tap-win32.c     | 92 ++++++++++++++++++++++++++++-------------------------
 net/tap.c           | 20 ++++++++----
 9 files changed, 216 insertions(+), 76 deletions(-)

-- 
1.8.5.3