xref: /dpdk/doc/guides/linux_gsg/build_dpdk.rst (revision 9599c59b4f86ea8d8098027cb541f3d32ca1631e)
1..  SPDX-License-Identifier: BSD-3-Clause
2    Copyright(c) 2010-2015 Intel Corporation.
3
4.. _linux_gsg_compiling_dpdk:
5
6Compiling the DPDK Target from Source
7=====================================
8
9Uncompress DPDK and Browse Sources
10----------------------------------
11
12First, uncompress the archive and move to the uncompressed DPDK source directory:
13
14.. code-block:: console
15
16    tar xJf dpdk-<version>.tar.xz
17    cd dpdk-<version>
18
19The DPDK is composed of several directories, including:
20
21*   doc: DPDK Documentation
22
23*   license: DPDK license information
24
25*   lib: Source code of DPDK libraries
26
27*   drivers: Source code of DPDK poll-mode drivers
28
29*   app: Source code of DPDK applications (automatic tests)
30
31*   examples: Source code of DPDK application examples
32
33*   config, buildtools: Framework-related scripts and configuration
34
35*   usertools: Utility scripts for end-users of DPDK applications
36
37*   devtools: Scripts for use by DPDK developers
38
39*   kernel: Kernel modules needed for some operating systems
40
41
42Compiling and Installing DPDK System-wide
43-----------------------------------------
44
45DPDK can be configured, built and installed on your system using the tools
46``meson`` and ``ninja``.
47
48
49DPDK Configuration
50~~~~~~~~~~~~~~~~~~
51
52To configure a DPDK build use:
53
54.. code-block:: console
55
56     meson setup <options> build
57
58where "build" is the desired output build directory, and "<options>" can be
59empty or one of a number of meson or DPDK-specific build options, described
60later in this section. The configuration process will finish with a summary
61of what DPDK libraries and drivers are to be built and installed, and for
62each item disabled, a reason why that is the case. This information can be
63used, for example, to identify any missing required packages for a driver.
64
65Once configured, to build and then install DPDK system-wide use:
66
67.. code-block:: console
68
69        cd build
70        ninja
71        meson install
72        ldconfig
73
74The last two commands above generally need to be run as root,
75with the `meson install` step copying the built objects to their final system-wide locations,
76and the last step causing the dynamic loader `ld.so` to update its cache to take account of the new objects.
77
78.. note::
79
80   On some linux distributions, such as Fedora or Redhat, paths in `/usr/local` are
81   not in the default paths for the loader. Therefore, on these
82   distributions, `/usr/local/lib` and `/usr/local/lib64` should be added
83   to a file in `/etc/ld.so.conf.d/` before running `ldconfig`.
84
85.. _adjusting_build_options:
86
87Adjusting Build Options
88~~~~~~~~~~~~~~~~~~~~~~~
89
90DPDK has a number of options that can be adjusted as part of the build configuration process.
91These options can be listed by running ``meson configure`` inside a configured build folder.
92Many of these options come from the "meson" tool itself and can be seen documented on the
93`Meson Website <https://mesonbuild.com/Builtin-options.html>`_.
94
95For example, to change the build-type from the default, "debugoptimized",
96to a regular "debug" build, you can either:
97
98* pass ``-Dbuildtype=debug`` or ``--buildtype=debug`` to meson when configuring the build folder initially
99
100* run ``meson configure -Dbuildtype=debug`` inside the build folder after the initial meson run.
101
102Other options are specific to the DPDK project but can be adjusted similarly.
103The "platform" option specifies a set a configuration parameters that will be used.
104The valid values are:
105
106* ``-Dplatform=native`` will tailor the configuration to the build machine.
107
108* ``-Dplatform=generic`` will use configuration that works on all machines
109  of the same architecture as the build machine.
110
111* ``-Dplatform=<SoC>`` will use configuration optimized for a particular SoC.
112  Consult the "socs" dictionary in ``config/arm/meson.build`` to see which
113  SoCs are supported.
114
115The instruction set will be set automatically by default according to these rules:
116
117* ``-Dplatform=native`` sets ``cpu_instruction_set`` to ``native``,
118  which configures ``-march`` (x86_64), ``-mcpu`` (ppc), ``-mtune`` (ppc) to ``native``.
119
120* ``-Dplatform=generic`` sets ``cpu_instruction_set`` to ``generic``,
121  which configures ``-march`` (x86_64), ``-mcpu`` (ppc), ``-mtune`` (ppc) to
122  a common minimal baseline needed for DPDK.
123
124To override what instruction set will be used, set the ``cpu_instruction_set``
125parameter to the instruction set of your choice (such as ``corei7``, ``power8``, etc.).
126
127``cpu_instruction_set`` is not used in Arm builds, as setting the instruction set
128without other parameters leads to inferior builds. The way to tailor Arm builds
129is to build for a SoC using ``-Dplatform=<SoC>`` mentioned above.
130
131The values determined by the ``platform`` parameter may be overwritten.
132For example, to set the ``max_lcores`` value to 256, you can either:
133
134* pass ``-Dmax_lcores=256`` to meson when configuring the build folder initially
135
136* run ``meson configure -Dmax_lcores=256`` inside the build folder after the initial meson run.
137
138Some of the DPDK sample applications in the `examples` directory can be
139automatically built as part of a meson build too.
140To do so, pass a comma-separated list of the examples to build to the
141`-Dexamples` meson option as below::
142
143  meson setup -Dexamples=l2fwd,l3fwd build
144
145As with other meson options, this can also be set post-initial-config using `meson configure` in the build directory.
146There is also a special value "all" to request that all example applications whose
147dependencies are met on the current system are built.
148When `-Dexamples=all` is set as a meson option, meson will check each example application to see if it can be built,
149and add all which can be built to the list of tasks in the ninja build configuration file.
150
151
152Building 32-bit DPDK on 64-bit Systems
153~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
154
155To build a 32-bit copy of DPDK on a 64-bit OS,
156the ``-m32`` flag should be passed to the compiler and linker
157to force the generation of 32-bit objects and binaries.
158This can be done either by setting ``CFLAGS`` and ``LDFLAGS`` in the environment,
159or by passing the value to meson using ``-Dc_args=-m32`` and ``-Dc_link_args=-m32``.
160For correctly identifying and using any dependency packages,
161the ``pkg-config`` tool must also be configured
162to look in the appropriate directory for .pc files for 32-bit libraries.
163This is done by setting ``PKG_CONFIG_LIBDIR`` to the appropriate path.
164
165The following meson command can be used on RHEL/Fedora systems to configure a 32-bit build,
166assuming the relevant 32-bit development packages, such as a 32-bit libc, are installed::
167
168  PKG_CONFIG_LIBDIR=/usr/lib/pkgconfig \
169      meson setup -Dc_args='-m32' -Dc_link_args='-m32' build
170
171For Debian/Ubuntu systems, the equivalent command is::
172
173  PKG_CONFIG_LIBDIR=/usr/lib/i386-linux-gnu/pkgconfig \
174      meson setup -Dc_args='-m32' -Dc_link_args='-m32' build
175
176Once the build directory has been configured,
177DPDK can be compiled using ``ninja`` as described above.
178
179
180.. _building_app_using_installed_dpdk:
181
182Building Applications Using Installed DPDK
183~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
184
185When installed system-wide, DPDK provides a pkg-config file ``libdpdk.pc`` for applications to query as part of their build.
186It's recommended that the pkg-config file be used, rather than hard-coding the parameters (cflags/ldflags)
187for DPDK into the application build process.
188
189An example of how to query and use the pkg-config file can be found in the ``Makefile`` of each of the example applications included with DPDK.
190A simplified example snippet is shown below, where the target binary name has been stored in the variable ``$(APP)``
191and the sources for that build are stored in ``$(SRCS-y)``.
192
193.. code-block:: makefile
194
195        PKGCONF = pkg-config
196
197        CFLAGS += -O3 $(shell $(PKGCONF) --cflags libdpdk)
198        LDFLAGS += $(shell $(PKGCONF) --libs libdpdk)
199
200        $(APP): $(SRCS-y) Makefile
201                $(CC) $(CFLAGS) $(SRCS-y) -o $@ $(LDFLAGS)
202
203.. note::
204
205   Unlike with the make build system present in older DPDK releases,
206   the meson system is not
207   designed to be used directly from a build directory. Instead it is
208   recommended that it be installed either system-wide or to a known
209   location in the user's home directory. The install location can be set
210   using the `--prefix` meson option (default: `/usr/local`).
211
212an equivalent build recipe for a simple DPDK application using meson as a
213build system is shown below:
214
215.. code-block:: python
216
217   project('dpdk-app', 'c')
218
219   dpdk = dependency('libdpdk')
220   sources = files('main.c')
221   executable('dpdk-app', sources, dependencies: dpdk)
222