On Wed, Jun 18, 2025 at 4:39 PM Laurent Vivier <lviv...@redhat.com> wrote: > > This series introduces support for passt as a new network backend for > QEMU. > > passt is a modern, unprivileged, user-mode networking solution that > provides guest connectivity by launching an external helper process. This > series adds the core backend and integrates it with vhost-user for > high-performance, accelerated networking. > > The series is structured to first improve the general networking code > before adding the new feature. The first patch extracts from the stream > backend the functions that will be reused in the passt backend. The > following patches are a preparatory refactoring to decouple the generic > vhost layer from specific backend implementations (tap, vhost-user, etc.). > This is achieved by replacing hardcoded type checks with a callback-based > system in NetClientInfo, making the vhost infrastructure more modular and > extensible. > > With the refactoring in place, subsequent patches introduce the passt > backend itself, reusing the generic stream handling logic. The final > patch adds vhost-user support to passt, which plugs cleanly into the > newly refactored vhost layer. > > Some benchmarks: > > Reference '-net user': > > -net user,hostfwd=tcp::10001-:10001 > > iperf3 -c localhost -p 10001 -t 60 -4 > > [ ID] Interval Transfer Bitrate Retr > [ 5] 0.00-60.00 sec 14.2 GBytes 2.03 Gbits/sec 1 > sender > [ 5] 0.00-60.00 sec 14.2 GBytes 2.03 Gbits/sec > receiver > > New backend '-netdev passt' > > -netdev passt,vhost-user=off,tcp-ports=10001 > > iperf3 -c localhost -p 10001 -t 60 -4 > > [ ID] Interval Transfer Bitrate Retr > [ 5] 0.00-60.00 sec 27.1 GBytes 3.88 Gbits/sec 0 > sender > [ 5] 0.00-60.03 sec 27.1 GBytes 3.88 Gbits/sec > receiver > > -netdev passt,vhost-user=on,tcp-ports=10001 > > iperf3 -c localhost -p 10001 -t 60 -4 > > [ ID] Interval Transfer Bitrate Retr > [ 5] 0.00-60.00 sec 224 GBytes 32.1 Gbits/sec 4 > sender > [ 5] 0.00-60.05 sec 224 GBytes 32.0 Gbits/sec > receiver
Do we have latency numbers of even PPS? Thanks > > Thanks, > Laurent > > Laurent Vivier (8): > net: Refactor stream logic for reuse in '-net passt' > net: Define net_client_set_link() > net: Introduce helper to identify vhost-user clients > net: Add get_vhost_net callback to NetClientInfo > net: Add get_acked_features callback to NetClientInfo > net: Add save_acked_features callback to NetClientInfo > net: Add passt network backend > net/passt: Implement vhost-user backend support > > hmp-commands.hx | 3 + > hw/net/vhost_net-stub.c | 1 - > hw/net/vhost_net.c | 89 ++--- > hw/net/virtio-net.c | 18 +- > include/net/net.h | 12 + > include/net/tap.h | 3 - > include/net/vhost-user.h | 19 -- > include/net/vhost-vdpa.h | 2 - > meson.build | 6 + > meson_options.txt | 2 + > net/clients.h | 4 + > net/hub.c | 3 + > net/meson.build | 6 +- > net/net.c | 55 ++- > net/passt.c | 718 +++++++++++++++++++++++++++++++++++++++ > net/stream.c | 282 ++++----------- > net/stream_data.c | 193 +++++++++++ > net/stream_data.h | 31 ++ > net/tap-win32.c | 5 - > net/tap.c | 20 +- > net/vhost-user-stub.c | 1 - > net/vhost-user.c | 22 +- > net/vhost-vdpa.c | 4 +- > qapi/net.json | 121 +++++++ > qemu-options.hx | 18 + > 25 files changed, 1293 insertions(+), 345 deletions(-) > delete mode 100644 include/net/vhost-user.h > create mode 100644 net/passt.c > create mode 100644 net/stream_data.c > create mode 100644 net/stream_data.h > > -- > 2.49.0 > >
