1Installing DPDK Using the meson build system 2============================================ 3 4Summary 5-------- 6For many platforms, compiling and installing DPDK should work using the 7following set of commands:: 8 9 meson build 10 cd build 11 ninja 12 ninja install 13 14This will compile DPDK in the ``build`` subdirectory, and then install the 15resulting libraries, drivers and header files onto the system - generally 16in /usr/local. A package-config file, ``libdpdk.pc``, for DPDK will also 17be installed to allow ease of compiling and linking with applications. 18 19After installation, to use DPDK, the necessary CFLAG and LDFLAG variables 20can be got from pkg-config:: 21 22 pkg-config --cflags libdpdk 23 pkg-config --libs libdpdk 24 25More detail on each of these steps can be got from the following sections. 26 27 28Getting the Tools 29------------------ 30 31The ``meson`` tool is used to configure a DPDK build. On most Linux 32distributions this can be got using the local package management system, 33e.g. ``dnf install meson`` or ``apt-get install meson``. If meson is not 34available as a suitable package, it can also be installed using the Python 353 ``pip`` tool, e.g. ``pip3 install meson``. Version 0.47.1 of meson is 36required - if the version packaged is too old, the latest version is 37generally available from "pip". 38 39The other dependency for building is the ``ninja`` tool, which acts similar 40to make and performs the actual build using information provided by meson. 41Installing meson will, in many cases, also install ninja, but, if not 42already installed, it too is generally packaged by most Linux distributions. 43If not available as a package, it can be downloaded as source or binary from 44https://ninja-build.org/ 45 46 47Configuring the Build 48---------------------- 49 50To configure a build, run the meson tool, passing the path to the directory 51to be used for the build e.g. ``meson build``, as shown above. If calling 52meson from somewhere other than the root directory of the DPDK project the 53path to the root directory should be passed as the first parameter, and the 54build path as the second. For example, to build DPDK in /tmp/dpdk-build:: 55 56 user@host:/tmp$ meson ~user/dpdk dpdk-build 57 58Meson will then configure the build based on settings in the project's 59meson.build files, and by checking the build environment for e.g. compiler 60properties or the presence of dependencies, such as libpcap, or openssl 61libcrypto libraries. Once done, meson writes a ``build.ninja`` file in the 62build directory to be used to do the build itself when ninja is called. 63 64Tuning of the build is possible, both as part of the original meson call, 65or subsequently using ``meson configure`` command (``mesonconf`` in some 66older versions). Some options, such as ``buildtype``, or ``werror`` are 67built into meson, while others, such as ``max_lcores``, or the list of 68examples to build, are DPDK-specific. To have a list of all options 69available run ``meson configure`` in the build directory. 70 71Examples of adjusting the defaults when doing initial meson configuration. 72Project-specific options are passed used -Doption=value:: 73 74 meson --werror werrorbuild # build with warnings as errors 75 76 meson --buildtype=debug debugbuild # build for debugging 77 78 meson -Dexamples=l3fwd,l2fwd fwdbuild # build some examples as 79 # part of the normal DPDK build 80 81 meson -Dmax_lcores=8 smallbuild # scale build for smaller systems 82 83 meson -Denable_docs=true fullbuild # build and install docs 84 85 meson -Dmachine=default # use builder-independent baseline -march 86 87 meson -Ddisable_drivers=event/*,net/tap # disable tap driver and all 88 # eventdev PMDs for a smaller build 89 90 meson -Denable_trace_fp=true tracebuild # build with fast path traces 91 # enabled 92 93Examples of setting some of the same options using meson configure:: 94 95 meson configure -Dwerror=true 96 97 meson configure -Dbuildtype=debug 98 99 meson configure -Dexamples=l3fwd,l2fwd 100 101 meson configure -Dmax_lcores=8 102 103 meson configure -Denable_trace_fp=true 104 105NOTE: once meson has been run to configure a build in a directory, it 106cannot be run again on the same directory. Instead ``meson configure`` 107should be used to change the build settings within the directory, and when 108``ninja`` is called to do the build itself, it will trigger the necessary 109re-scan from meson. 110 111NOTE: machine=default uses a config that works on all supported architectures 112regardless of the capabilities of the machine where the build is happening. 113 114As well as those settings taken from ``meson configure``, other options 115such as the compiler to use can be passed via environment variables. For 116example:: 117 118 CC=clang meson clang-build 119 120NOTE: for more comprehensive overriding of compilers or other environment 121settings, the tools for cross-compilation may be considered. However, for 122basic overriding of the compiler etc., the above form works as expected. 123 124 125Performing the Build 126--------------------- 127 128Use ``ninja`` to perform the actual build inside the build folder 129previously configured. In most cases no arguments are necessary. 130 131Ninja accepts a number of flags which are similar to make. For example, to 132call ninja from outside the build folder, you can use ``ninja -C build``. 133Ninja also runs parallel builds by default, but you can limit this using 134the ``-j`` flag, e.g. ``ninja -j1 -v`` to do the build one step at a time, 135printing each command on a new line as it runs. 136 137 138Installing the Compiled Files 139------------------------------ 140 141Use ``ninja install`` to install the required DPDK files onto the system. 142The install prefix defaults to ``/usr/local`` but can be used as with other 143options above. The environment variable ``DESTDIR`` can be used to adjust 144the root directory for the install, for example when packaging. 145 146With the base install directory, the individual directories for libraries 147and headers are configurable. By default, the following will be the 148installed layout:: 149 150 headers -> /usr/local/include 151 libraries -> /usr/local/lib64 152 drivers -> /usr/local/lib64/dpdk/drivers 153 libdpdk.pc -> /usr/local/lib64/pkgconfig 154 155For the drivers, these will also be symbolically linked into the library 156install directory, so that ld.so can find them in cases where one driver may 157depend on another, e.g. a NIC PMD depending upon the PCI bus driver. Within 158the EAL, the default search path for drivers will be set to the configured 159driver install path, so dynamically-linked applications can be run without 160having to pass in ``-d /path/to/driver`` options for standard drivers. 161 162 163Cross Compiling DPDK 164-------------------- 165 166To cross-compile DPDK on a desired target machine we can use the following 167command:: 168 169 meson cross-build --cross-file <target_machine_configuration> 170 171For example if the target machine is arm64 we can use the following 172command:: 173 174 meson arm-build --cross-file config/arm/arm64_armv8_linux_gcc 175 176where config/arm/arm64_armv8_linux_gcc contains settings for the compilers 177and other build tools to be used, as well as characteristics of the target 178machine. 179 180Using the DPDK within an Application 181------------------------------------- 182 183To compile and link against DPDK within an application, pkg-config should 184be used to query the correct parameters. Examples of this are given in the 185makefiles for the example applications included with DPDK. They demonstrate 186how to link either against the DPDK shared libraries, or against the static 187versions of the same. 188 189From examples/helloworld/Makefile:: 190 191 PC_FILE := $(shell pkg-config --path libdpdk) 192 CFLAGS += -O3 $(shell pkg-config --cflags libdpdk) 193 LDFLAGS_SHARED = $(shell pkg-config --libs libdpdk) 194 LDFLAGS_STATIC = $(shell pkg-config --static --libs libdpdk) 195 196 build/$(APP)-shared: $(SRCS-y) Makefile $(PC_FILE) | build 197 $(CC) $(CFLAGS) $(SRCS-y) -o $@ $(LDFLAGS) $(LDFLAGS_SHARED) 198 199 build/$(APP)-static: $(SRCS-y) Makefile $(PC_FILE) | build 200 $(CC) $(CFLAGS) $(SRCS-y) -o $@ $(LDFLAGS) $(LDFLAGS_STATIC) 201 202 build: 203 @mkdir -p $@ 204