12. Enable DPDK on OpenWrt

This document describes how to enable Data Plane Development Kit (DPDK) on OpenWrt in both a virtual and physical x86 environment.

12.1. Introduction

The OpenWrt project is a well-known source-based router OS which provides a fully writable filesystem with package management.

12.2. Build OpenWrt

You can obtain OpenWrt image through https://downloads.openwrt.org/releases. To fully customize your own OpenWrt, it is highly recommended to build it from the source code. You can clone the OpenWrt source code as follows:

git clone https://git.openwrt.org/openwrt/openwrt.git

12.2.1. OpenWrt configuration

  • Select x86 in Target System

  • Select x86_64 in Subtarget

  • Select Build the OpenWrt SDK for cross-compilation environment

  • Select Use glibc in Advanced configuration options (for developers) then ToolChain Options and C Library implementation

12.2.2. Kernel configuration

The following configurations should be enabled:

  • CONFIG_VFIO_IOMMU_TYPE1=y

  • CONFIG_VFIO_VIRQFD=y

  • CONFIG_VFIO=y

  • CONFIG_VFIO_NOIOMMU=y

  • CONFIG_VFIO_PCI=y

  • CONFIG_VFIO_PCI_MMAP=y

  • CONFIG_HUGETLBFS=y

  • CONFIG_HUGETLB_PAGE=y

  • CONFIG_PROC_PAGE_MONITOR=y

12.2.3. Build steps

For detailed OpenWrt build steps and prerequisites, please refer to the OpenWrt build guide.

After the build is completed, you can find the images and SDK in <OpenWrt Root>/bin/targets/x86/64-glibc/.

12.3. DPDK Cross Compilation for OpenWrt

12.3.1. Pre-requisites

NUMA is required to run DPDK in x86.

Note

For compiling the NUMA lib, run libtool --version to ensure the libtool version >= 2.2, otherwise the compilation will fail with errors.

git clone https://github.com/numactl/numactl.git
cd numactl
git checkout v2.0.13 -b v2.0.13
./autogen.sh
autoconf -i
export PATH=<OpenWrt SDK>/glibc/openwrt-sdk-x86-64_gcc-8.3.0_glibc.Linux-x86_64/staging_dir/toolchain-x86_64_gcc-8.3.0_glibc/bin/:$PATH
./configure CC=x86_64-openwrt-linux-gnu-gcc --prefix=<OpenWrt SDK toolchain dir>
make install

The numa header files and lib file is generated in the include and lib folder respectively under <OpenWrt SDK toolchain dir>.

12.3.2. Build DPDK

To cross compile with meson build, you need to write a customized cross file first.

[binaries]
c = 'x86_64-openwrt-linux-gcc'
cpp = 'x86_64-openwrt-linux-cpp'
ar = 'x86_64-openwrt-linux-ar'
strip = 'x86_64-openwrt-linux-strip'

meson setup builddir --cross-file openwrt-cross
ninja -C builddir

12.4. Running DPDK application on OpenWrt

12.4.1. Virtual machine

  • Extract the boot image

gzip -d openwrt-x86-64-combined-ext4.img.gz

  • Launch Qemu

qemu-system-x86_64 \
        -cpu host \
        -smp 8 \
        -enable-kvm \
        -M q35 \
        -m 2048M \
        -object memory-backend-file,id=mem,size=2048M,mem-path=/tmp/hugepages,share=on \
        -drive file=<Your OpenWrt images folder>/openwrt-x86-64-combined-ext4.img,id=d0,if=none,bus=0,unit=0 \
        -device ide-hd,drive=d0,bus=ide.0 \
        -net nic,vlan=0 \
        -net nic,vlan=1 \
        -net user,vlan=1 \
        -display none \

12.4.2. Physical machine

You can use the dd tool to write the OpenWrt image to the drive you want to write the image on.

dd if=openwrt-18.06.1-x86-64-combined-squashfs.img of=/dev/sdX

Where sdX is name of the drive. (You can find it though fdisk -l)

12.4.3. Running DPDK

More detailed info about how to run a DPDK application please refer to Running DPDK Applications section of the DPDK documentation.

Note

You need to install pre-built NUMA libraries (including soft link) to /usr/lib64 in OpenWrt.