"Kinsella, Ray" <m...@ashroe.eu> writes:
> On 08/02/2021 16:52, Aaron Conole wrote:
>> The DPDK testing infrastructure includes a comprehensive set of
>> libraries, utilities, and CI integrations for developers to test
>> their code changes. This isn't well documented, however.
>>
>> Document the basics for adding a test suite to the infrastructure
>> and enabling that test suite for continuous integration platforms
>> so that newer developers can understand how to develop test suites
>> and test cases.
>>
>> Signed-off-by: Aaron Conole <acon...@redhat.com>
>> ---
>> v0: Added information for TEST_SKIPPED and details about generating
>> code coverage to help with ideas for writing unit test cases.
>>
>> doc/guides/contributing/index.rst | 1 +
>> doc/guides/contributing/testing.rst | 231 ++++++++++++++++++++++++++++
>> 2 files changed, 232 insertions(+)
>> create mode 100644 doc/guides/contributing/testing.rst
>>
>> diff --git a/doc/guides/contributing/index.rst
>> b/doc/guides/contributing/index.rst
>> index 2fefd91931..41909d949b 100644
>> --- a/doc/guides/contributing/index.rst
>> +++ b/doc/guides/contributing/index.rst
>> @@ -14,6 +14,7 @@ Contributor's Guidelines
>> abi_versioning
>> documentation
>> patches
>> + testing
>> vulnerability
>> stable
>> cheatsheet
>> diff --git a/doc/guides/contributing/testing.rst
>> b/doc/guides/contributing/testing.rst
>> new file mode 100644
>> index 0000000000..3ade654772
>> --- /dev/null
>> +++ b/doc/guides/contributing/testing.rst
>> @@ -0,0 +1,231 @@
>> +.. SPDX-License-Identifier: BSD-3-Clause
>> + Copyright 2018 The DPDK contributors
>> +
>> +.. _testing_guidelines:
>> +
>> +DPDK Testing Guidelines
>> +=======================
>> +
>> +This document outlines the guidelines for running and adding new
>> +tests to the in-tree DPDK test suites.
>> +
>> +The DPDK test suite model is loosely based on the xunit model, where
>> +tests are grouped into test suites, and suites are run by runners.
>> +For a basic overview, see the basic Wikipedia article on xunit:
>> +`xUnit - Wikipedia <https://en.wikipedia.org/wiki/XUnit>`_.
>> +
>> +
>> +Running a test
>> +--------------
>> +
>> +DPDK tests are run via the main test runniner, the `dpdk-test` app.
>
> runner
D'oh!
>> +The `dpdk-test` app is a command-line interface that facilitates
>> +running various tests or test suites.
>> +
>> +There are two modes of operation. The first mode is as an interactive
>> +command shell that allows launching specific test suites. This is
>> +the default operating mode of `dpdk-test` and can be done by::
>
> is the double :: intentional?
Yes - it designates the next block as a code block.
>> +
>> + $ ./build/app/test/dpdk-test --dpdk-options-here
>> + EAL: Detected 4 lcore(s)
>> + EAL: Detected 1 NUMA nodes
>> + EAL: Static memory layout is selected, amount of reserved memory
>> can be adjusted with -m or --socket-mem
>> + EAL: Multi-process socket /run/user/26934/dpdk/rte/mp_socket
>> + EAL: Selected IOVA mode 'VA'
>> + EAL: Probing VFIO support...
>> + EAL: PCI device 0000:00:1f.6 on NUMA socket -1
>> + EAL: Invalid NUMA socket, default to 0
>> + EAL: probe driver: 8086:15d7 net_e1000_em
>> + APP: HPET is not enabled, using TSC as default timer
>> + RTE>>
>> +
>> +At the prompt, simply type the name of the test suite you wish to run
>> +and it will execute.
>> +
>> +The second form is useful for a scripting environment, and is used by
>> +the DPDK meson build system. This mode is invoked by assigning a
>> +specific test suite name to the environment variable `DPDK_TEST`
>> +before invoking the `dpdk-test` command, such as::
>> +
>> + $ DPDK_TEST=version_autotest ./build/app/test/dpdk-test --no-huge
>
> better to say --dpdk-options-here instead of --no-huge, as above.
Okay, I can do that.
>> + EAL: Detected 4 lcore(s)
>> + EAL: Detected 1 NUMA nodes
>> + EAL: Static memory layout is selected, amount of reserved memory
>> can be adjusted with -m or --socket-mem
>> + EAL: Multi-process socket /run/user/26934/dpdk/rte/mp_socket
>> + EAL: Selected IOVA mode 'VA'
>> + EAL: Probing VFIO support...
>> + EAL: PCI device 0000:00:1f.6 on NUMA socket -1
>> + EAL: Invalid NUMA socket, default to 0
>> + EAL: probe driver: 8086:15d7 net_e1000_em
>> + APP: HPET is not enabled, using TSC as default timer
>> + RTE>>version_autotest
>> + Version string: 'DPDK 20.02.0-rc0'
>> + Test OK
>> + RTE>>$
>> +
>> +The above shows running a specific test case. On success, the return
>> +code will be '0', otherwise it will be set to some error value (such
>> +as '255').
>> +
>> +
>> +Running all tests
>> +-----------------
>> +
>> +In order to allow developers to quickly execute all the standard
>> +internal tests without needing to remember or look up each test suite
>> +name, the build system includes a standard way of executing the
>> +default test suites. After building via `ninja`, the ``meson test``
>> +command will execute the standard tests and report errors.
>> +
>> +There are four groups of default test suites. The first group is
>> +the **fast** test suite, which is the largest group of test cases.
>> +These are the bulk of the unit tests to validate functional blocks.
>> +The second group is the **perf** tests. These test suites can take
>> +longer to run and do performance evaluations. The third group is
>> +the **driver** test suite, which is mostly for special hardware
>> +related testing (such as `cryptodev`). The last group are the
>> +**debug** tests. These mostly are used to dump system information.
>> +
>> +The suites can be selected by adding the ``--suite`` option to the
>> +``meson test`` command. Ex: ``meson test --suite fast-tests``
>
> show some console output in this section?
Okay.
>> +
>> +
>> +Adding test suites
>> +------------------
>> +
>> +To add a testsuite to the DPDK test application, create a new test
>> +file for that suite (ex: see *app/test/test_version.c* for the
>> +``version_autotest`` test suite). There are two useful things:
>
> There are two useful things?
Okay, I will rephrase because it sounds awkward. But I don't think it's
wrong ;)
>> +
>> + 1. REGISTER_TEST_COMMAND(command_name, function_to_execute)
>> + Registers a test command with the name `command_name` and which
>> + runs the function `function_to_execute` when `command_name` is
>> + invoked.
>> +
>> + 2. unit_test_suite_runner(struct unit_test_suite \*)
>> + Returns a runner for a full test suite object, which contains
>> + a test suite name, setup, teardown, and vector of unit test
>> + cases.
>> +
>> +Each test suite has a setup and teardown function that runs at the
>> +beginning and end of the test suite execution. Each unit test has
>> +a similar function for test case setup and teardown.
>> +
>> +Adding test cases is controlled via the `.unit_test_cases` element
>
> Test cases are added to the .unit_test_cases element of the
> of the unit test suite structure.
Will rephrase.
>> +of the unit test suite. Ex:
>> +
>> +.. code-block:: c
>> + :linenos:
>> +
>> + #include <time.h>
>> +
>> + #include <rte_common.h>
>> + #include <rte_cycles.h>
>> + #include <rte_hexdump.h>
>> + #include <rte_random.h>
>> +
>> + #include "test.h"
>> +
>> + static int testsuite_setup(void) { return TEST_SUCCESS; }
>> + static void testsuite_teardown(void) { }
>> +
>> + static int ut_setup(void) { return TEST_SUCCESS; }
>> + static void ut_teardown(void) { }
>> +
>> + static int test_case_first(void) { return TEST_SUCCESS; }
>> +
>> + static struct unit_test_suite example_testsuite = {
>> + .suite_name = "EXAMPLE TEST SUITE",
>> + .setup = testsuite_setup,
>> + .teardown = testsuite_teardown,
>> + .unit_test_cases = {
>> + TEST_CASE_ST(ut_setup, ut_teardown, test_case_first),
>> +
>> + TEST_CASES_END(), /**< NULL terminate unit test array */
>> + },
>> + };
>> +
>> + static int example_tests()
>> + {
>> + return unit_test_suite_runner(&example_testsuite);
>> + }
>> +
>> + REGISTER_TEST_COMMAND(example_autotest, example_tests);
>> +
>> +The above code block is a small example that can be used to create a
>> +complete test suite with test case.
>> +
>> +
>> +Designing a test
>> +----------------
>> +
>> +Test cases have multiple ways of indicating an error has occurred,
>> +in order to reflect failure state back to the runner. Using the
>> +various methods of indicating errors can assist in not only validating
>> +the requisite functionality is working, but also to help debug when
>> +a change in environment or code has caused things to go wrong.
>> +
>> +The first way to indicate a generic error is by returning a test
>> +result failure, using the *TEST_FAILED* error code. This is the most
>> +basic way of indicating that an error has occurred in a test routine.
>> +It isn't very informative to the user, so it should really be used in
>> +cases where the test has catastrophically failed.
>> +
>> +The preferred method of indicating an error is via the
>> +`RTE_TEST_ASSERT` family of macros, which will immediately return
>> +*TEST_FAILED* error condition, but will also log details about the
>> +failure. The basic form is:
>> +
>> +.. code-block:: c
>> +
>> + RTE_TEST_ASSERT(cond, msg, ...)
>> +
>> +In the above macro, *cond* is the condition to evaluate to **true**.
>> +Any generic condition can go here. The *msg* parameter will be a
>> +message to display if *cond* evaluates to **false**. Some specialized
>> +macros already exist. See `lib/librte_eal/include/rte_test.h` for
>> +a list of pre-build test assertions.
>> +
>> +Sometimes it is important to indicate that a test needs to be
>> +skipped, either because the environment isn't able to support running
>> +the test, or because some requisite functionality isn't availble. The
>
> available
D'oh!
>> +test suite supports returning a result of `TEST_SKIPPED` during test
>> +case setup, or during test case execution to indicate that the
>> +preconditions of the test aren't available. A skipped test isn't the
>> +same as a failed test. Failed tests indicate that all required
>> +functionality was enabled, and the environment was correct but the
>> +test failed due to some error in logic. A skipped test indicates
>> +that the test setup wasn't available to run.
>
> Simpler to provide an example of a skipped test, than a long explanation?
I can do both.
>> +
>> +
>> +Checking code coverage
>> +----------------------
>> +One of the best ways to help design a test case is to add a new test
>> +which exercises functionality that doesn't currently have a test case.
>> +The best way to find these is to run the test suite with some
>> +additional code coverage reporting turned on.
>
> I would drop the previous sentences.
> They would just confuse a reader looking to generate code coverage.
Okay. I felt it was a bit strange to introduce code coverage here, and
I thought it was a needed bridge. I can drop it.
>> The meson build system
>> +supports generating a code coverage report via the `-Db_coverage=true`
>> +option, in conjunction with a package like **lcov**, to generate an
>> +HTML code coverage report. Example::
>> +
>> + $ meson covered -Db_coverage=true
>> + $ meson test -C covered --suite fast-tests
>> + $ ninja coverage-html -C covered
>> +
>> +The above will generate an html report in the
>> +`covered/meson-logs/coveragereport/` directory that can be explored
>> +for detailed code covered information. This can be used to assist
>> +in test development.
>> +
>> +
>> +Adding a suite to the default
>> +-----------------------------
>> +
>> +Adding to one of the default tests involves editing the appropriate
>> +meson build file `app/test/meson.build` and adding the command to
>> +the correct test suite class. Once added, the new test suite will
>> +be run as part of the appropriate class (fast, perf, driver, etc.).
>> +
>> +Some of these default test suites are run during continuous integration
>> +tests, making regression checking automatic for new patches submitted
>> +to the project.
>>
