在虚拟化环境中使用DPDK内核NIC接口

时间:2016-06-04 03:28:51

标签: linux virtual-machine qemu dpdk

我将在笔记本电脑上开发DPDK Linux应用程序,但DPDK不支持笔记本电脑的硬件。幸运的是,DPDK supports半虚拟化设备包括QEMUvirtio-net

所以我正在尝试配置QEMU来宾,以便在virtio-net-pci设备上运行Kernel NIC Interface(KNI)。问题是KNI示例应用程序不接受virtio-net-pci驱动程序。

QEMU命令

exec qemu-system-x86_64 -enable-kvm \
  -cpu host -smp 2 \
  -vga std \
  -mem-prealloc -mem-path /dev/hugepages \
  -drive file=GentooVM.img,if=virtio \
  -netdev user,id=vmnic,hostname=gentoo \
  -device virtio-net-pci,netdev=vmnic \
  -m 1024M \
  -monitor stdio \
  -name "Gentoo VM"

在来宾中运行KNI示例应用

sudo ./examples/kni/build/app/kni -c 0x3 -n 4 -- \
-P -p 0x1 --config="(0,0,1)"

EAL: Detected lcore 0 as core 0 on socket 0
EAL: Detected lcore 1 as core 0 on socket 0
EAL: Support maximum 128 logical core(s) by configuration.
EAL: Detected 2 lcore(s)
EAL: Probing VFIO support...
EAL:   IOMMU type 1 (Type 1) is supported
EAL:   IOMMU type 8 (No-IOMMU) is not supported
EAL: VFIO support initialized
EAL: Setting up physically contiguous memory...
...
EAL: WARNING: cpu flags constant_tsc=yes nonstop_tsc=no -> using
unreliable clock cycles !
EAL: Master lcore 0 is ready (tid=657d58c0;cpuset=[0])
PMD: rte_igbvf_pmd_init():  >>
EAL: lcore 1 is ready (tid=305ff700;cpuset=[1])
EAL: PCI device 0000:00:03.0 on NUMA socket -1
EAL:   probe driver: 1af4:1000 rte_virtio_pmd
EAL:   Not managed by a supported kernel driver(0), skipped
PMD: virtio_read_caps(): failed to map pci device!
PMD: vtpci_init(): trying with legacy virtio pci.
Segmentation fault

在访客

中输出lspci命令
...
00:03.0 Ethernet controller: Red Hat, Inc Virtio network device

我注意到pci_scan_one()函数集dev->kdrv = RTE_KDRV_NONE,而驱动程序被检测为virtio-pci(来自/sys/bus/pci/devices/0000:00:03.0/driver)。

TAP网络

TAP网络仍然存在同样的问题。在主机上,我从Wi-Fi接口配置了一个网桥,并将其连接到TAP接口:

wifi_iface=wlp3s0
br_iface=br0
br_network='172.20.0.1/16'
br_dhcp_range='172.20.0.2,172.20.255.254'
tap_iface=tap0
user=ruslan

ip link add name $br_iface type bridge
ip addr add "$br_network" dev $br_iface
ip link set $br_iface up
dnsmasq --interface=$br_iface --bind-interfaces \
  --dhcp-range=$br_dhcp_range

modprobe tun
chmod 0666 /dev/net/tun

ip tuntap add dev $tap_iface mode tap user "$user"
ip link set $tap_iface up promisc on
ip link set $tap_iface master $br_iface

sysctl net.ipv4.ip_forward=1
sysctl net.ipv6.conf.default.forwarding=1
sysctl net.ipv6.conf.all.forwarding=1

iptables -t nat -A POSTROUTING -o $wifi_iface -j MASQUERADE
iptables -A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
iptables -A FORWARD -i $tap_iface -o $wifi_iface -j ACCEPT

QEMU命令:

sudo qemu-system-x86_64 -enable-kvm \
  -cpu host -smp 2 \
  -vga std \
  -mem-prealloc -mem-path /dev/hugepages \
  -drive file=GentooVM.img,if=virtio \
  -netdev tap,id=vm1_p1,ifname=tap0,script=no,downscript=no,vhost=on \
  -device virtio-net-pci,netdev=vm1_p1,bus=pci.0,addr=0x3,ioeventfd=on \
  -m 1024M \
  -monitor stdio \
  -name "Gentoo VM" \
  $@
来宾中输出

ifconfig

enp0s3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 172.20.196.253  netmask 255.255.0.0  broadcast 172.20.255.255
        inet6 fe80::59c1:f175:aeb3:433  prefixlen 64  scopeid 0x20<link>
        ether 52:54:00:12:34:56  txqueuelen 1000  (Ethernet)
        RX packets 9  bytes 1039 (1.0 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 21  bytes 1802 (1.7 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

以下命令的失败方式与上面“用户”网络的情况相同:

sudo ./examples/kni/build/app/kni -c 0x3 -n 4 -- \
-P -p 0x1 --config="(0,0,1)"
...
EAL: PCI device 0000:00:03.0 on NUMA socket -1
EAL:   probe driver: 1af4:1000 rte_virtio_pmd
EAL:   Not managed by a supported kernel driver(0), skipped
PMD: virtio_read_caps(): failed to map pci device!
PMD: vtpci_init(): trying with legacy virtio pci.

问题

是否可以使用virtio-net-pci设备运行 KNI

如果不可能,还有其他选择在虚拟化环境中开发 DPDK KNI 应用程序吗?

2 个答案:

答案 0 :(得分:2)

virtio_read_caps()无法映射PCI设备,因为DPDK需要binding network ports到以下内核模块之一:

  • uio_pci_generic
  • igb_uio
  • vfio-pci
  

从版本1.4开始,DPDK应用程序不再自动解除绑定   所有受支持的网络端口都来自正在使用的内核驱动代替,   必须绑定DPDK应用程序要使用的所有端口   申请前的uio_pci_genericigb_uiovfio-pci模块   运行。 Linux *控制下的任何网络端口都将被忽略   DPDK轮询模式驱动程序,不能被应用程序使用。

因此,在运行DPDK KNI应用程序之前,我们应该

  1. 至少加载一个受支持的I / O内核模块(uio_pci_genericigb_uiovfio-pci
  2. 加载$RTE_SDK/$RTE_TARGET/kmod/rte_kni.ko
  3. 通过$RTE_SDK/tools/dpdk_nic_bind.py脚本将网络端口绑定到内核模块。
  4. 例如:

    $ sudo insmod $RTE_SDK/$RTE_TARGET/kmod/igb_uio.ko
    $ sudo insmod $RTE_SDK/$RTE_TARGET/kmod/rte_kni.ko
    # Obtain ID of the network port
    $ python2 $RTE_SDK/tools/dpdk_nic_bind.py --status
    Network devices using DPDK-compatible driver
    ============================================
    0000:00:03.0 'Virtio network device' drv=igb_uio unused=vfio-pci,uio_pci_generic
    $ sudo python2 $RTE_SDK/tools/dpdk_nic_bind.py --bind=igb_uio 0000:00:03.0
    

    ,其中

    • $RTE_SDK - 指向DPDK安装目录。
    • $RTE_TARGET - 指向DPDK目标环境目录。

答案 1 :(得分:1)

我非常确定-netdev user与您想要的内容不兼容,因为它传递的是TCP数据而不是整个以太网帧。根据{{​​3}}

  

用户网络是使用&#34; slirp&#34;实现的,它在QEMU中提供完整的TCP / IP堆栈,并使用该堆栈实现虚拟NAT网络。

您希望您的选项更像http://wiki.qemu.org/Documentation/Networking

中指定的选项
-netdev tap,id=vm1_p1,ifname=tap0,script=no,vhost=on
-device virtio-net-pci,netdev=vm1_p1,bus=pci.0,addr=0x3,ioeventfd=on