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+.. SPDX-License-Identifier: GPL-2.0
+
+===============
+Getting Started
+===============
+
+Installing dependencies
+=======================
+KUnit has the same dependencies as the Linux kernel. As long as you can build
+the kernel, you can run KUnit.
+
+KUnit Wrapper
+=============
+Included with KUnit is a simple Python wrapper that helps format the output to
+easily use and read KUnit output. It handles building and running the kernel, as
+well as formatting the output.
+
+The wrapper can be run with:
+
+.. code-block:: bash
+
+ ./tools/testing/kunit/kunit.py run
+
+Creating a kunitconfig
+======================
+The Python script is a thin wrapper around Kbuild as such, it needs to be
+configured with a ``kunitconfig`` file. This file essentially contains the
+regular Kernel config, with the specific test targets as well.
+
+.. code-block:: bash
+
+ git clone -b master https://kunit.googlesource.com/kunitconfig $PATH_TO_KUNITCONFIG_REPO
+ cd $PATH_TO_LINUX_REPO
+ ln -s $PATH_TO_KUNIT_CONFIG_REPO/kunitconfig kunitconfig
+
+You may want to add kunitconfig to your local gitignore.
+
+Verifying KUnit Works
+---------------------
+
+To make sure that everything is set up correctly, simply invoke the Python
+wrapper from your kernel repo:
+
+.. code-block:: bash
+
+ ./tools/testing/kunit/kunit.py run
+
+.. note::
+ You may want to run ``make mrproper`` first.
+
+If everything worked correctly, you should see the following:
+
+.. code-block:: bash
+
+ Generating .config ...
+ Building KUnit Kernel ...
+ Starting KUnit Kernel ...
+
+followed by a list of tests that are run. All of them should be passing.
+
+.. note::
+ Because it is building a lot of sources for the first time, the ``Building
+ kunit kernel`` step may take a while.
+
+Writing your first test
+=======================
+
+In your kernel repo let's add some code that we can test. Create a file
+``drivers/misc/example.h`` with the contents:
+
+.. code-block:: c
+
+ int misc_example_add(int left, int right);
+
+create a file ``drivers/misc/example.c``:
+
+.. code-block:: c
+
+ #include <linux/errno.h>
+
+ #include "example.h"
+
+ int misc_example_add(int left, int right)
+ {
+ return left + right;
+ }
+
+Now add the following lines to ``drivers/misc/Kconfig``:
+
+.. code-block:: kconfig
+
+ config MISC_EXAMPLE
+ bool "My example"
+
+and the following lines to ``drivers/misc/Makefile``:
+
+.. code-block:: make
+
+ obj-$(CONFIG_MISC_EXAMPLE) += example.o
+
+Now we are ready to write the test. The test will be in
+``drivers/misc/example-test.c``:
+
+.. code-block:: c
+
+ #include <kunit/test.h>
+ #include "example.h"
+
+ /* Define the test cases. */
+
+ static void misc_example_add_test_basic(struct kunit *test)
+ {
+ KUNIT_EXPECT_EQ(test, 1, misc_example_add(1, 0));
+ KUNIT_EXPECT_EQ(test, 2, misc_example_add(1, 1));
+ KUNIT_EXPECT_EQ(test, 0, misc_example_add(-1, 1));
+ KUNIT_EXPECT_EQ(test, INT_MAX, misc_example_add(0, INT_MAX));
+ KUNIT_EXPECT_EQ(test, -1, misc_example_add(INT_MAX, INT_MIN));
+ }
+
+ static void misc_example_test_failure(struct kunit *test)
+ {
+ KUNIT_FAIL(test, "This test never passes.");
+ }
+
+ static struct kunit_case misc_example_test_cases[] = {
+ KUNIT_CASE(misc_example_add_test_basic),
+ KUNIT_CASE(misc_example_test_failure),
+ {}
+ };
+
+ static struct kunit_suite misc_example_test_suite = {
+ .name = "misc-example",
+ .test_cases = misc_example_test_cases,
+ };
+ kunit_test_suite(misc_example_test_suite);
+
+Now add the following to ``drivers/misc/Kconfig``:
+
+.. code-block:: kconfig
+
+ config MISC_EXAMPLE_TEST
+ bool "Test for my example"
+ depends on MISC_EXAMPLE && KUNIT
+
+and the following to ``drivers/misc/Makefile``:
+
+.. code-block:: make
+
+ obj-$(CONFIG_MISC_EXAMPLE_TEST) += example-test.o
+
+Now add it to your ``kunitconfig``:
+
+.. code-block:: none
+
+ CONFIG_MISC_EXAMPLE=y
+ CONFIG_MISC_EXAMPLE_TEST=y
+
+Now you can run the test:
+
+.. code-block:: bash
+
+ ./tools/testing/kunit/kunit.py
+
+You should see the following failure:
+
+.. code-block:: none
+
+ ...
+ [16:08:57] [PASSED] misc-example:misc_example_add_test_basic
+ [16:08:57] [FAILED] misc-example:misc_example_test_failure
+ [16:08:57] EXPECTATION FAILED at drivers/misc/example-test.c:17
+ [16:08:57] This test never passes.
+ ...
+
+Congrats! You just wrote your first KUnit test!
+
+Next Steps
+==========
+* Check out the :doc:`usage` page for a more
+ in-depth explanation of KUnit.