.. BSD LICENSE
- Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
+ Copyright(c) 2010-2015 Intel Corporation. All rights reserved.
All rights reserved.
Redistribution and use in source and binary forms, with or without
.. code-block:: console
- user@target:~$ qemu-system-x86_64 ... \
+ qemu-system-x86_64 ... \
-netdev tap,id=hostnet1,vhost=on,vhostfd=<open fd> \
-device virtio-net-pci, netdev=hostnet1,id=net1 \
-netdev tap,id=hostnet2,vhost=on,vhostfd=<open fd> \
.. code-block:: console
- user@target:~$ qemu-system-x86_64 ... \
+ qemu-system-x86_64 ... \
-chardev socket,id=char1,path=<sock_path> \
-netdev type=vhost-user,id=hostnet1,chardev=char1 \
-device virtio-net-pci,netdev=hostnet1,id=net1 \
.. code-block:: console
export RTE_SDK=/path/to/rte_sdk
- cd ${RTE_SDK}/examples/vhost
+ cd ${RTE_SDK}/examples/vhost/build/app
#. Run the vhost-switch sample code:
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir / mnt/huge -- -p 0x1 --dev-basename usvhost
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- -p 0x1 --dev-basename usvhost
vhost user: a socket file named usvhost will be created under current directory. Use its path as the socket path in guest's qemu commandline.
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir / mnt/huge -- -p 0x1 --dev-basename usvhost
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- -p 0x1 --dev-basename usvhost
.. note::
Please note the huge-dir parameter instructs the DPDK to allocate its memory from the 2 MB page hugetlbfs.
+.. note::
+
+ The number used with the --socket-mem parameter may need to be more than 1024.
+ The number required depends on the number of mbufs allocated by vhost-switch.
+
Parameters
~~~~~~~~~~
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir / mnt/huge -- -p 0x1 --dev-basename usvhost
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- -p 0x1 --dev-basename usvhost
**vm2vm.**
The vm2vm parameter disable/set mode of packet switching between guests in the host.
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir /mnt/huge -- --vm2vm [0,1,2]
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- --vm2vm [0,1,2]
**Mergeable Buffers.**
The mergeable buffers parameter controls how virtio-net descriptors are used for virtio-net headers.
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir / mnt/huge -- --mergeable [0,1]
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- --mergeable [0,1]
**Stats.**
The stats parameter controls the printing of virtio-net device statistics.
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir / mnt/huge -- --stats [0,n]
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- --stats [0,n]
**RX Retry.**
The rx-retry option enables/disables enqueue retries when the guests RX queue is full.
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir / mnt/huge -- --rx-retry [0,1]
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- --rx-retry [0,1]
**RX Retry Number.**
The rx-retry-num option specifies the number of retries on an RX burst,
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir / mnt/huge -- --rx-retry 1 --rx-retry-num 5
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- --rx-retry 1 --rx-retry-num 5
**RX Retry Delay Time.**
The rx-retry-delay option specifies the timeout (in micro seconds) between retries on an RX burst,
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir / mnt/huge -- --rx-retry 1 --rx-retry-delay 20
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- --rx-retry 1 --rx-retry-delay 20
**Zero copy.**
The zero copy option enables/disables the zero copy mode for RX/TX packet,
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir /mnt/huge -- --zero-copy [0,1]
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- --zero-copy [0,1]
**RX descriptor number.**
The RX descriptor number option specify the Ethernet RX descriptor number,
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir /mnt/huge -- --zero-copy 1 --rx-desc-num [0, n]
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- --zero-copy 1 --rx-desc-num [0, n]
**TX descriptor number.**
The TX descriptor number option specify the Ethernet TX descriptor number, it is valid only in zero copy mode is enabled.
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir /mnt/huge -- --zero-copy 1 --tx-desc-num [0, n]
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- --zero-copy 1 --tx-desc-num [0, n]
**VLAN strip.**
The VLAN strip option enable/disable the VLAN strip on host, if disabled, the guest will receive the packets with VLAN tag.
.. code-block:: console
- user@target:~$ ./build/app/vhost-switch -c f -n 4 --huge-dir /mnt/huge -- --vlan-strip [0, 1]
+ ./vhost-switch -c f -n 4 --socket-mem 1024 --huge-dir /mnt/huge \
+ -- --vlan-strip [0, 1]
Running the Virtual Machine (QEMU)
----------------------------------
.. code-block:: console
- user@target:~$ qemu-system-x86_64 ... -device virtio-net-pci,netdev=hostnet1,id=net1 ...
+ qemu-system-x86_64 ... -device virtio-net-pci,netdev=hostnet1, \
+ id=net1 ...
* Ensure the guest's virtio-net network adapter is configured with offloads disabled.
.. code-block:: console
- user@target:~$ qemu-system-x86_64 ... -device virtio-net-pci,netdev=hostnet1,id=net1,csum=off,gso=off,guest_tso4=off,guest_tso6=off,guest_ecn=off
+ qemu-system-x86_64 ... -device virtio-net-pci,netdev=hostnet1, \
+ id=net1, csum=off,gso=off,guest_tso4=off,guest_tso6=off,guest_ecn=off
* Redirect QEMU to communicate with the DPDK vhost-net sample code in place of the vhost-net kernel module(vhost cuse).
.. code-block:: console
- user@target:~$ qemu-system-x86_64 ... -netdev tap,id=hostnet1,vhost=on,vhostfd=<open fd> ...
+ qemu-system-x86_64 ... -netdev tap,id=hostnet1,vhost=on, \
+ vhostfd=<open fd> ...
* Enable the vhost-net sample code to map the VM's memory into its own process address space.
.. code-block:: console
- user@target:~$ qemu-system-x86_64 ... -mem-prealloc -mem-path / dev/hugepages ...
+ qemu-system-x86_64 ... -mem-prealloc -mem-path /dev/hugepages ...
.. note::
#!/usr/bin/python
fd = os.open("/dev/usvhost-1", os.O_RDWR)
- subprocess.call("qemu-system-x86_64 ... . -netdev tap,id=vhostnet0,vhost=on,vhostfd=" + fd +"...", shell=True)
+ subprocess.call
+ ("qemu-system-x86_64 ... -netdev tap,id=vhostnet0,vhost=on,vhostfd="
+ + fd +"...", shell=True)
.. note::
.. code-block:: console
- user@target:~$ qemu-system-x86_64 ... -mem-prealloc -mem-path / dev/hugepages ...
+ qemu-system-x86_64 ... -mem-prealloc -mem-path /dev/hugepages ...
.. note::
This process is automated in the QEMU wrapper script discussed in Section 24.7.3.
- The following two sections only applies to vhost cuse. For vhost-user, please make corresponding changes to qemu-wrapper script and guest XML file.
+ The following two sections only applies to vhost cuse.
+ For vhost-user, please make corresponding changes to qemu-wrapper script and guest XML file.
QEMU Wrapper Script
~~~~~~~~~~~~~~~~~~~
.. code-block:: console
- user@target:~$ qemu-wrap.py -machine pc-i440fx-1.4,accel=kvm,usb=off -cpu SandyBridge -smp 4,sockets=4,cores=1,threads=1
- -netdev tap,id=hostnet1,vhost=on -device virtio-net-pci,netdev=hostnet1,id=net1 -hda <disk img> -m 4096
+ qemu-wrap.py -machine pc-i440fx-1.4,accel=kvm,usb=off \
+ -cpu SandyBridge -smp 4,sockets=4,cores=1,threads=1 \
+ -netdev tap,id=hostnet1,vhost=on \
+ -device virtio-net-pci,netdev=hostnet1,id=net1 \
+ -hda <disk img> -m 4096
which will become the following call to QEMU:
.. code-block:: console
- /usr/local/bin/qemu-system-x86_64 -machine pc-i440fx-1.4,accel=kvm,usb=off -cpu SandyBridge -smp 4,sockets=4,cores=1,threads=1
- -netdev tap,id=hostnet1,vhost=on,vhostfd=<open fd> -device virtio-net-pci,netdev=hostnet1,id=net1,
- csum=off,gso=off,guest_tso4=off,guest_tso6=off,guest_ecn=off -hda <disk img> -m 4096 -mem-path /dev/hugepages -mem-prealloc
+ qemu-system-x86_64 -machine pc-i440fx-1.4,accel=kvm,usb=off \
+ -cpu SandyBridge -smp 4,sockets=4,cores=1,threads=1 \
+ -netdev tap,id=hostnet1,vhost=on,vhostfd=<open fd> \
+ -device virtio-net-pci,netdev=hostnet1,id=net1, \
+ csum=off,gso=off,guest_tso4=off,guest_tso6=off,guest_ecn=off \
+ -hda <disk img> -m 4096 -mem-path /dev/hugepages -mem-prealloc
Libvirt Integration
~~~~~~~~~~~~~~~~~~~
.. code-block:: console
- user@target:~$ mkdir /dev/cgroup
- user@target:~$ mount -t cgroup none /dev/cgroup -o devices
+ mkdir /dev/cgroup
+ mount -t cgroup none /dev/cgroup -o devices
* Restart the libvirtd system process
.. code-block:: console
- user@target:~$ x86_64-native-linuxapp-gcc/app/testpmd -c 0x3 -- n 4 -socket-mem 128 -- --burst=64 -i
+ cd ${RTE_SDK}/x86_64-native-linuxapp-gcc/app
+ ./testpmd -c 0x3 -n 4 --socket-mem 512 \
+ -- --burst=64 --i --disable-hw-vlan-filter
The destination MAC address for packets transmitted on each port can be set at the command line:
.. code-block:: console
- user@target:~$ x86_64-native-linuxapp-gcc/app/testpmd -c 0x3 -- n 4 -socket-mem 128 -- --burst=64 -i --eth- peer=0,aa:bb:cc:dd:ee:ff --eth-peer=1,ff,ee,dd,cc,bb,aa
+ ./testpmd -c 0x3 -n 4 --socket-mem 512 \
+ -- --burst=64 --i --disable-hw-vlan-filter \
+ --eth-peer=0,aa:bb:cc:dd:ee:ff --eth-peer=1,ff:ee:dd:cc:bb:aa
* Packets received on port 1 will be forwarded on port 0 to MAC address
- aa:bb:cc:dd:ee:ff.
+ aa:bb:cc:dd:ee:ff
* Packets received on port 0 will be forwarded on port 1 to MAC address
- ff,ee,dd,cc,bb,aa.
+ ff:ee:dd:cc:bb:aa
The testpmd application can then be configured to act as an L2 forwarding application: