diff options
Diffstat (limited to 'Documentation/dev-tools')
| -rw-r--r-- | Documentation/dev-tools/kselftest.rst | 22 | ||||
| -rw-r--r-- | Documentation/dev-tools/kunit/architecture.rst | 4 | ||||
| -rw-r--r-- | Documentation/dev-tools/kunit/start.rst | 7 | ||||
| -rw-r--r-- | Documentation/dev-tools/kunit/usage.rst | 69 |
4 files changed, 97 insertions, 5 deletions
diff --git a/Documentation/dev-tools/kselftest.rst b/Documentation/dev-tools/kselftest.rst index 6e35d042199c..deede972f254 100644 --- a/Documentation/dev-tools/kselftest.rst +++ b/Documentation/dev-tools/kselftest.rst @@ -169,6 +169,28 @@ the `-t` option for specific single tests. Either can be used multiple times:: For other features see the script usage output, seen with the `-h` option. +Timeout for selftests +===================== + +Selftests are designed to be quick and so a default timeout is used of 45 +seconds for each test. Tests can override the default timeout by adding +a settings file in their directory and set a timeout variable there to the +configured a desired upper timeout for the test. Only a few tests override +the timeout with a value higher than 45 seconds, selftests strives to keep +it that way. Timeouts in selftests are not considered fatal because the +system under which a test runs may change and this can also modify the +expected time it takes to run a test. If you have control over the systems +which will run the tests you can configure a test runner on those systems to +use a greater or lower timeout on the command line as with the `-o` or +the `--override-timeout` argument. For example to use 165 seconds instead +one would use: + + $ ./run_kselftest.sh --override-timeout 165 + +You can look at the TAP output to see if you ran into the timeout. Test +runners which know a test must run under a specific time can then optionally +treat these timeouts then as fatal. + Packaging selftests =================== diff --git a/Documentation/dev-tools/kunit/architecture.rst b/Documentation/dev-tools/kunit/architecture.rst index e95ab05342bb..f335f883f8f6 100644 --- a/Documentation/dev-tools/kunit/architecture.rst +++ b/Documentation/dev-tools/kunit/architecture.rst @@ -119,9 +119,9 @@ All expectations/assertions are formatted as: terminated immediately. - Assertions call the function: - ``void __noreturn kunit_abort(struct kunit *)``. + ``void __noreturn __kunit_abort(struct kunit *)``. - - ``kunit_abort`` calls the function: + - ``__kunit_abort`` calls the function: ``void __noreturn kunit_try_catch_throw(struct kunit_try_catch *try_catch)``. - ``kunit_try_catch_throw`` calls the function: diff --git a/Documentation/dev-tools/kunit/start.rst b/Documentation/dev-tools/kunit/start.rst index c736613c9b19..a98235326bab 100644 --- a/Documentation/dev-tools/kunit/start.rst +++ b/Documentation/dev-tools/kunit/start.rst @@ -250,15 +250,20 @@ Now we are ready to write the test cases. }; kunit_test_suite(misc_example_test_suite); + MODULE_LICENSE("GPL"); + 2. Add the following lines to ``drivers/misc/Kconfig``: .. code-block:: kconfig config MISC_EXAMPLE_TEST tristate "Test for my example" if !KUNIT_ALL_TESTS - depends on MISC_EXAMPLE && KUNIT=y + depends on MISC_EXAMPLE && KUNIT default KUNIT_ALL_TESTS +Note: If your test does not support being built as a loadable module (which is +discouraged), replace tristate by bool, and depend on KUNIT=y instead of KUNIT. + 3. Add the following lines to ``drivers/misc/Makefile``: .. code-block:: make diff --git a/Documentation/dev-tools/kunit/usage.rst b/Documentation/dev-tools/kunit/usage.rst index 9faf2b4153fc..c27e1646ecd9 100644 --- a/Documentation/dev-tools/kunit/usage.rst +++ b/Documentation/dev-tools/kunit/usage.rst @@ -121,6 +121,12 @@ there's an allocation error. ``return`` so they only work from the test function. In KUnit, we stop the current kthread on failure, so you can call them from anywhere. +.. note:: + Warning: There is an exception to the above rule. You shouldn't use assertions + in the suite's exit() function, or in the free function for a resource. These + run when a test is shutting down, and an assertion here prevents further + cleanup code from running, potentially leading to a memory leak. + Customizing error messages -------------------------- @@ -160,7 +166,12 @@ many similar tests. In order to reduce duplication in these closely related tests, most unit testing frameworks (including KUnit) provide the concept of a *test suite*. A test suite is a collection of test cases for a unit of code with optional setup and teardown functions that run before/after the whole -suite and/or every test case. For example: +suite and/or every test case. + +.. note:: + A test case will only run if it is associated with a test suite. + +For example: .. code-block:: c @@ -190,7 +201,10 @@ after everything else. ``kunit_test_suite(example_test_suite)`` registers the test suite with the KUnit test framework. .. note:: - A test case will only run if it is associated with a test suite. + The ``exit`` and ``suite_exit`` functions will run even if ``init`` or + ``suite_init`` fail. Make sure that they can handle any inconsistent + state which may result from ``init`` or ``suite_init`` encountering errors + or exiting early. ``kunit_test_suite(...)`` is a macro which tells the linker to put the specified test suite in a special linker section so that it can be run by KUnit @@ -601,6 +615,57 @@ For example: KUNIT_ASSERT_STREQ(test, buffer, ""); } +Registering Cleanup Actions +--------------------------- + +If you need to perform some cleanup beyond simple use of ``kunit_kzalloc``, +you can register a custom "deferred action", which is a cleanup function +run when the test exits (whether cleanly, or via a failed assertion). + +Actions are simple functions with no return value, and a single ``void*`` +context argument, and fulfill the same role as "cleanup" functions in Python +and Go tests, "defer" statements in languages which support them, and +(in some cases) destructors in RAII languages. + +These are very useful for unregistering things from global lists, closing +files or other resources, or freeing resources. + +For example: + +.. code-block:: C + + static void cleanup_device(void *ctx) + { + struct device *dev = (struct device *)ctx; + + device_unregister(dev); + } + + void example_device_test(struct kunit *test) + { + struct my_device dev; + + device_register(&dev); + + kunit_add_action(test, &cleanup_device, &dev); + } + +Note that, for functions like device_unregister which only accept a single +pointer-sized argument, it's possible to directly cast that function to +a ``kunit_action_t`` rather than writing a wrapper function, for example: + +.. code-block:: C + + kunit_add_action(test, (kunit_action_t *)&device_unregister, &dev); + +``kunit_add_action`` can fail if, for example, the system is out of memory. +You can use ``kunit_add_action_or_reset`` instead which runs the action +immediately if it cannot be deferred. + +If you need more control over when the cleanup function is called, you +can trigger it early using ``kunit_release_action``, or cancel it entirely +with ``kunit_remove_action``. + Testing Static Functions ------------------------ |