56. Installing DPDK Using the meson build system

56.1. Summary

For many platforms, compiling and installing DPDK should work using the following set of commands:

meson build
cd build
ninja
ninja install

This will compile DPDK in the build subdirectory, and then install the resulting libraries, drivers and header files onto the system - generally in /usr/local. A package-config file, libdpdk.pc, for DPDK will also be installed to allow ease of compiling and linking with applications.

After installation, to use DPDK, the necessary CFLAG and LDFLAG variables can be got from pkg-config:

pkg-config --cflags libdpdk
pkg-config --libs libdpdk

More detail on each of these steps can be got from the following sections.

56.2. Getting the Tools

The meson tool is used to configure a DPDK build. On most Linux distributions this can be got using the local package management system, e.g. dnf install meson or apt-get install meson. If meson is not available as a suitable package, it can also be installed using the Python 3 pip tool, e.g. pip3 install meson. Version 0.47.1 of meson is required - if the version packaged is too old, the latest version is generally available from “pip”.

The other dependency for building is the ninja tool, which acts similar to make and performs the actual build using information provided by meson. Installing meson will, in many cases, also install ninja, but, if not already installed, it too is generally packaged by most Linux distributions. If not available as a package, it can be downloaded as source or binary from https://ninja-build.org/

56.3. Configuring the Build

To configure a build, run the meson tool, passing the path to the directory to be used for the build e.g. meson build, as shown above. If calling meson from somewhere other than the root directory of the DPDK project the path to the root directory should be passed as the first parameter, and the build path as the second. For example, to build DPDK in /tmp/dpdk-build:

user@host:/tmp$ meson ~user/dpdk dpdk-build

Meson will then configure the build based on settings in the project’s meson.build files, and by checking the build environment for e.g. compiler properties or the presence of dependencies, such as libpcap, or openssl libcrypto libraries. Once done, meson writes a build.ninja file in the build directory to be used to do the build itself when ninja is called.

Tuning of the build is possible, both as part of the original meson call, or subsequently using meson configure command (mesonconf in some older versions). Some options, such as buildtype, or werror are built into meson, while others, such as max_lcores, or the list of examples to build, are DPDK-specific. To have a list of all options available run meson configure in the build directory.

Examples of adjusting the defaults when doing initial meson configuration. Project-specific options are passed used -Doption=value:

meson --werror werrorbuild  # build with warnings as errors

meson --buildtype=debug debugbuild  # build for debugging

meson -Dexamples=l3fwd,l2fwd fwdbuild  # build some examples as
                                # part of the normal DPDK build

meson -Dmax_lcores=8 smallbuild  # scale build for smaller systems

meson -Denable_docs=true fullbuild  # build and install docs

meson -Dmachine=default  # use builder-independent baseline -march

meson -Ddisable_drivers=event/*,net/tap  # disable tap driver and all
                                # eventdev PMDs for a smaller build

meson -Denable_trace_fp=true tracebuild # build with fast path traces
                                # enabled

Examples of setting some of the same options using meson configure:

meson configure -Dwerror=true

meson configure -Dbuildtype=debug

meson configure -Dexamples=l3fwd,l2fwd

meson configure -Dmax_lcores=8

meson configure -Denable_trace_fp=true

NOTE: once meson has been run to configure a build in a directory, it cannot be run again on the same directory. Instead meson configure should be used to change the build settings within the directory, and when ninja is called to do the build itself, it will trigger the necessary re-scan from meson.

NOTE: machine=default uses a config that works on all supported architectures regardless of the capabilities of the machine where the build is happening.

As well as those settings taken from meson configure, other options such as the compiler to use can be passed via environment variables. For example:

CC=clang meson clang-build

NOTE: for more comprehensive overriding of compilers or other environment settings, the tools for cross-compilation may be considered. However, for basic overriding of the compiler etc., the above form works as expected.

56.4. Performing the Build

Use ninja to perform the actual build inside the build folder previously configured. In most cases no arguments are necessary.

Ninja accepts a number of flags which are similar to make. For example, to call ninja from outside the build folder, you can use ninja -C build. Ninja also runs parallel builds by default, but you can limit this using the -j flag, e.g. ninja -j1 -v to do the build one step at a time, printing each command on a new line as it runs.

56.5. Installing the Compiled Files

Use ninja install to install the required DPDK files onto the system. The install prefix defaults to /usr/local but can be used as with other options above. The environment variable DESTDIR can be used to adjust the root directory for the install, for example when packaging.

With the base install directory, the individual directories for libraries and headers are configurable. By default, the following will be the installed layout:

headers -> /usr/local/include
libraries -> /usr/local/lib64
drivers -> /usr/local/lib64/dpdk/drivers
libdpdk.pc -> /usr/local/lib64/pkgconfig

For the drivers, these will also be symbolically linked into the library install directory, so that ld.so can find them in cases where one driver may depend on another, e.g. a NIC PMD depending upon the PCI bus driver. Within the EAL, the default search path for drivers will be set to the configured driver install path, so dynamically-linked applications can be run without having to pass in -d /path/to/driver options for standard drivers.

56.6. 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>

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

meson arm-build --cross-file config/arm/arm64_armv8_linux_gcc

where config/arm/arm64_armv8_linux_gcc contains settings for the compilers and other build tools to be used, as well as characteristics of the target machine.

56.7. Using the DPDK within an Application

To compile and link against DPDK within an application, pkg-config should be used to query the correct parameters. Examples of this are given in the makefiles for the example applications included with DPDK. They demonstrate how to link either against the DPDK shared libraries, or against the static versions of the same.

From examples/helloworld/Makefile:

PC_FILE := $(shell pkg-config --path libdpdk)
CFLAGS += -O3 $(shell pkg-config --cflags libdpdk)
LDFLAGS_SHARED = $(shell pkg-config --libs libdpdk)
LDFLAGS_STATIC = -Wl,-Bstatic $(shell pkg-config --static --libs libdpdk)

build/$(APP)-shared: $(SRCS-y) Makefile $(PC_FILE) | build
        $(CC) $(CFLAGS) $(SRCS-y) -o $@ $(LDFLAGS) $(LDFLAGS_SHARED)

build/$(APP)-static: $(SRCS-y) Makefile $(PC_FILE) | build
        $(CC) $(CFLAGS) $(SRCS-y) -o $@ $(LDFLAGS) $(LDFLAGS_STATIC)

build:
        @mkdir -p $@