4. Cross compile DPDK for ARM64

This chapter describes how to cross compile DPDK for ARM64 from x86 build hosts.

Note

Whilst it is recommended to natively build DPDK on ARM64 (just like with x86), it is also possible to cross-build DPDK for ARM64. An ARM64 cross compile GNU toolchain is used for this.

4.1. Obtain the cross tool chain

The latest cross compile tool chain can be downloaded from: https://developer.arm.com/open-source/gnu-toolchain/gnu-a/downloads.

Following is the step to get the version 8.2, latest one at the time of this writing.

wget https://developer.arm.com/-/media/Files/downloads/gnu-a/8.2-2019.01/gcc-arm-8.2-2019.01-x86_64-aarch64-linux-gnu.tar.xz

4.2. Unzip and add into the PATH

tar -xvf gcc-arm-8.2-2019.01-x86_64-aarch64-linux-gnu.tar.xz
export PATH=$PATH:<cross_install_dir>/gcc-arm-8.2-2019.01-x86_64-aarch64-linux-gnu/bin

Note

For the host requirements and other info, refer to the release note section: https://releases.linaro.org/components/toolchain/binaries/

4.3. Getting the prerequisite library

NUMA is required by most modern machines, not needed for non-NUMA architectures.

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 v2.0.11 -b v2.0.11
./autogen.sh
autoconf -i
./configure --host=aarch64-linux-gnu CC=aarch64-linux-gnu-gcc --prefix=<numa install dir>
make install

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

4.4. Augment the cross toolchain with NUMA support

Note

This way is optional, an alternative is to use extra CFLAGS and LDFLAGS, depicted in Configure and cross compile DPDK Build below.

Copy the NUMA header files and lib to the cross compiler’s directories:

cp <numa_install_dir>/include/numa*.h <cross_install_dir>/gcc-arm-8.2-2019.01-x86_64-aarch64-linux-gnu/bin/../aarch64-linux-gnu/libc/usr/include/
cp <numa_install_dir>/lib/libnuma.a <cross_install_dir>/gcc-arm-8.2-2019.01-x86_64-aarch64-linux-gnu/lib/gcc/aarch64-linux-gnu/8.2/

4.5. Configure and cross compile DPDK Build

To configure a build, choose one of the target configurations, like arm64-dpaa2-linux-gcc and arm64-thunderx-linux-gcc.

make config T=arm64-armv8a-linux-gcc

To cross-compile, without compiling the kernel modules, use the following command:

make -j CROSS=aarch64-linux-gnu- CONFIG_RTE_KNI_KMOD=n CONFIG_RTE_EAL_IGB_UIO=n

To cross-compile, including the kernel modules, the kernel source tree needs to be specified by setting RTE_KERNELDIR:

make -j CROSS=aarch64-linux-gnu- RTE_KERNELDIR=<kernel_src_rootdir> CROSS_COMPILE=aarch64-linux-gnu-

To compile for non-NUMA targets, without compiling the kernel modules, use the following command:

make -j CROSS=aarch64-linux-gnu- CONFIG_RTE_KNI_KMOD=n CONFIG_RTE_EAL_IGB_UIO=n CONFIG_RTE_LIBRTE_VHOST_NUMA=n CONFIG_RTE_EAL_NUMA_AWARE_HUGEPAGES=n

Note

1. EXTRA_CFLAGS and EXTRA_LDFLAGS should be added to include the NUMA headers and link the library respectively, if the above step Augment the cross toolchain with NUMA support was skipped therefore the toolchain was not augmented with NUMA support.

2. “-isystem <numa_install_dir>/include” should be add to EXTRA_CFLAGS, otherwise the numa.h file will get a lot of compiling errors of Werror=cast-qual, Werror=strict-prototypes and Werror=old-style-definition.

An example is given below:

make -j CROSS=aarch64-linux-gnu- CONFIG_RTE_KNI_KMOD=n CONFIG_RTE_EAL_IGB_UIO=n EXTRA_CFLAGS="-isystem <numa_install_dir>/include" EXTRA_LDFLAGS="-L<numa_install_dir>/lib -lnuma"

4.6. Meson Cross Compiling DPDK

To cross-compile DPDK on a desired target machine we can use the following command:

meson cross-build --cross-file <target_machine_configuration>
ninja -C cross-build

For example if the target machine is arm64 we can use the following command:

meson arm64-build --cross-file config/arm/arm64_armv8_linux_gcc
ninja -C arm64-build