This series introduces support for passt as a new network backend for
QEMU.
The purpose of this new backend is to help to use passt daemon as
easily as the user backend ('-nic passt' as we have '-nic user').
All the passt functionalities will not be available to keep it simple,
and the goal is not to be supported by libvirt, as in these cases the
best way to use passt will be to use stream or vhost-user backend
with an externaly started passt daemon.
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 and vhost-net, 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
v4:
- back to v2 parameters (except debug and trace parameters) + v3 generic
"param"
- update documentation
v3:
- tested with
-nic passt
and
-nic passt,model=virtio,vhost-user=on
and fixed passt_check_peer_type()
- moved new fields from NetClientInfo to vhost-net struct
- Remove most of the hardcoded parameters to introduce a generic
"param" parameter, like:
-nic passt,param=--tcp-ports=10001,param=--udp-ports=10001
- added patches:
vhost_net: Rename vhost_set_vring_enable() for clarity
net: Add is_vhost_user flag to vhost_net struct
(this one replaces "net: Introduce helper to identify vhost-user clients")
- update documentation
v2:
- rebase:
fix conflict with
837b87c4c5ba ("net/stream: skip automatic zero-init of large array")
- add path parameter to provide path of passt if it is not in PATH
- add 2 patches:
"net: Allow network backends to advertise max TX queue size"
"net: Consolidate vhost feature bits into NetClientInfo"
Thanks,
Laurent
Laurent Vivier (11):
net: Refactor stream logic for reuse in '-net passt'
net: Define net_client_set_link()
vhost_net: Rename vhost_set_vring_enable() for clarity
net: Add get_vhost_net callback to NetClientInfo
net: Consolidate vhost feature bits into vhost_net structure
net: Add get_acked_features callback to VhostNetOptions
net: Add save_acked_features callback to vhost_net
net: Allow network backends to advertise max TX queue size
net: Add is_vhost_user flag to vhost_net struct
net: Add passt network backend
net/passt: Implement vhost-user backend support
docs/system/devices/net.rst | 50 ++-
hmp-commands.hx | 3 +
hw/net/vhost_net-stub.c | 3 +-
hw/net/vhost_net.c | 145 +------
hw/net/virtio-net.c | 36 +-
include/hw/virtio/vhost.h | 5 +
include/net/net.h | 3 +
include/net/tap.h | 3 -
include/net/vhost-user.h | 19 -
include/net/vhost-vdpa.h | 4 -
include/net/vhost_net.h | 10 +-
meson.build | 6 +
meson_options.txt | 2 +
net/clients.h | 4 +
net/hub.c | 3 +
net/meson.build | 6 +-
net/net.c | 36 +-
net/passt.c | 753 ++++++++++++++++++++++++++++++++++
net/stream.c | 282 +++----------
net/stream_data.c | 193 +++++++++
net/stream_data.h | 31 ++
net/tap-win32.c | 5 -
net/tap.c | 43 +-
net/vhost-user-stub.c | 1 -
net/vhost-user.c | 60 ++-
net/vhost-vdpa.c | 11 +-
qapi/net.json | 118 ++++++
qemu-options.hx | 153 ++++++-
scripts/meson-buildoptions.sh | 3 +
29 files changed, 1564 insertions(+), 427 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
