ceph/src/seastar/dpdk/doc/guides/prog_guide/extend_dpdk.rst

   1 ..  SPDX-License-Identifier: BSD-3-Clause
   2     Copyright(c) 2010-2014 Intel Corporation.
   3
   4 Extending the DPDK
   5 =========================
   6
   7 This chapter describes how a developer can extend the DPDK to provide a new library,
   8 a new target, or support a new target.
   9
  10 Example: Adding a New Library libfoo
  11 ------------------------------------
  12
  13 To add a new library to the DPDK, proceed as follows:
  14
  15 #. Add a new configuration option:
  16
  17    .. code-block:: bash
  18
  19         for f in config/\*; do \
  20             echo CONFIG_RTE_LIBFOO=y >> $f; done
  21
  22 #. Create a new directory with sources:
  23
  24    .. code-block:: console
  25
  26         mkdir ${RTE_SDK}/lib/libfoo
  27         touch ${RTE_SDK}/lib/libfoo/foo.c
  28         touch ${RTE_SDK}/lib/libfoo/foo.h
  29
  30 #. Add a foo() function in libfoo.
  31
  32     Definition is in foo.c:
  33
  34     .. code-block:: c
  35
  36         void foo(void)
  37         {
  38         }
  39
  40     Declaration is in foo.h:
  41
  42     .. code-block:: c
  43
  44         extern void foo(void);
  45
  46
  47 #. Update lib/Makefile:
  48
  49     .. code-block:: console
  50
  51         vi ${RTE_SDK}/lib/Makefile
  52         # add:
  53         # DIRS-$(CONFIG_RTE_LIBFOO) += libfoo
  54
  55 #. Create a new Makefile for this library, for example, derived from mempool Makefile:
  56
  57     .. code-block:: console
  58
  59         cp ${RTE_SDK}/lib/librte_mempool/Makefile ${RTE_SDK}/lib/libfoo/
  60
  61         vi ${RTE_SDK}/lib/libfoo/Makefile
  62         # replace:
  63         # librte_mempool -> libfoo
  64         # rte_mempool -> foo
  65
  66
  67 #. Update mk/DPDK.app.mk, and add -lfoo in LDLIBS variable when the option is enabled.
  68    This will automatically add this flag when linking a DPDK application.
  69
  70
  71 #. Build the DPDK with the new library (we only show a specific target here):
  72
  73     .. code-block:: console
  74
  75         cd ${RTE_SDK}
  76         make config T=x86_64-native-linux-gcc
  77         make
  78
  79
  80 #. Check that the library is installed:
  81
  82     .. code-block:: console
  83
  84         ls build/lib
  85         ls build/include
  86
  87 Example: Using libfoo in the Test Application
  88 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  89
  90 The test application is used to validate all functionality of the DPDK.
  91 Once you have added a library, a new test case should be added in the test application.
  92
  93 *   A new test_foo.c file should be added, that includes foo.h and calls the foo() function from test_foo().
  94     When the test passes, the test_foo() function should return 0.
  95
  96 *   Makefile, test.h and commands.c must be updated also, to handle the new test case.
  97
  98 *   Test report generation: autotest.py is a script that is used to generate the test report that is available in the
  99     ${RTE_SDK}/doc/rst/test_report/autotests directory. This script must be updated also.
 100     If libfoo is in a new test family, the links in ${RTE_SDK}/doc/rst/test_report/test_report.rst must be updated.
 101
 102 *   Build the DPDK with the updated test application (we only show a specific target here):
 103
 104
 105     .. code-block:: console
 106
 107         cd ${RTE_SDK}
 108         make config T=x86_64-native-linux-gcc
 109         make