Add `example_params_test_with_init` to illustrate how to manage shared resources across parameterized KUnit tests. This example showcases the use of the new `param_init` function and its registration to a test using the `KUNIT_CASE_PARAM_WITH_INIT` macro.
Additionally, the test demonstrates: - How to directly assign a static parameter array to a test via `kunit_register_params_array`. - Leveraging the Resource API for test resource management.
Signed-off-by: Marie Zhussupova marievic@google.com --- lib/kunit/kunit-example-test.c | 112 +++++++++++++++++++++++++++++++++ 1 file changed, 112 insertions(+)
diff --git a/lib/kunit/kunit-example-test.c b/lib/kunit/kunit-example-test.c index 3056d6bc705d..5bf559e243f6 100644 --- a/lib/kunit/kunit-example-test.c +++ b/lib/kunit/kunit-example-test.c @@ -277,6 +277,116 @@ static void example_slow_test(struct kunit *test) KUNIT_EXPECT_EQ(test, 1 + 1, 2); }
+/* + * This custom function allocates memory for the kunit_resource data field. + * The function is passed to kunit_alloc_resource() and executed once + * by the internal helper __kunit_add_resource(). + */ +static int example_resource_init(struct kunit_resource *res, void *context) +{ + int *info = kmalloc(sizeof(*info), GFP_KERNEL); + + if (!info) + return -ENOMEM; + *info = *(int *)context; + res->data = info; + return 0; +} + +/* + * This function deallocates memory for the 'kunit_resource' data field. + * The function is passed to kunit_alloc_resource() and automatically + * executes within kunit_release_resource() when the resource's reference + * count, via kunit_put_resource(), drops to zero. KUnit uses reference + * counting to ensure that resources are not freed prematurely. + */ +static void example_resource_free(struct kunit_resource *res) +{ + kfree(res->data); +} + +/* + * This match function is invoked by kunit_find_resource() to locate + * a test resource based on defined criteria. The current example + * uniquely identifies the resource by its free function; however, + * alternative custom criteria can be implemented. Refer to + * lib/kunit/platform.c and lib/kunit/static_stub.c for further examples. + */ +static bool example_resource_alloc_match(struct kunit *test, + struct kunit_resource *res, + void *match_data) +{ + return res->data && res->free == example_resource_free; +} + +/* + * This is an example of a function that provides a description for each of the + * parameters. + */ +static void example_param_array_get_desc(const void *p, char *desc) +{ + const struct example_param *param = p; + + snprintf(desc, KUNIT_PARAM_DESC_SIZE, + "example check if %d is less than or equal to 3", param->value); +} + +/* + * Initializes the parent kunit struct for parameterized KUnit tests. + * This function enables sharing resources across all parameterized + * tests by adding them to the `parent` kunit test struct. It also supports + * registering either static or dynamic arrays of test parameters. + */ +static int example_param_init(struct kunit *test) +{ + int ctx = 3; /* Data to be stored. */ + int arr_size = ARRAY_SIZE(example_params_array); + + /* + * This allocates a struct kunit_resource, sets its data field to + * ctx, and adds it to the kunit struct's resources list. Note that + * this is test managed so we don't need to have a custom exit function + * to free it. + */ + void *data = kunit_alloc_resource(test, example_resource_init, example_resource_free, + GFP_KERNEL, &ctx); + + if (!data) + return -ENOMEM; + /* Pass the static param array information to the parent struct kunit. */ + kunit_register_params_array(test, example_params_array, arr_size, + example_param_array_get_desc); + return 0; +} + +/* + * This is an example of a parameterized test that uses shared resources + * available from the struct kunit parent field of the kunit struct. + */ +static void example_params_test_with_init(struct kunit *test) +{ + int threshold; + struct kunit_resource *res; + const struct example_param *param = test->param_value; + + /* By design, param pointer will not be NULL. */ + KUNIT_ASSERT_NOT_NULL(test, param); + + /* Here we access the parent pointer of the test to find the shared resource. */ + res = kunit_find_resource(test->parent, example_resource_alloc_match, NULL); + + KUNIT_ASSERT_NOT_NULL(test, res); + + /* Since the data field in kunit_resource is a void pointer we need to typecast it. */ + threshold = *((int *)res->data); + + /* Assert that the parameter is less than or equal to a certain threshold. */ + KUNIT_ASSERT_LE(test, param->value, threshold); + + /* This decreases the reference count after calling kunit_find_resource(). */ + kunit_put_resource(res); +} + /* * Here we make a list of all the test cases we want to add to the test suite * below. @@ -296,6 +406,8 @@ static struct kunit_case example_test_cases[] = { KUNIT_CASE(example_static_stub_using_fn_ptr_test), KUNIT_CASE(example_priv_test), KUNIT_CASE_PARAM(example_params_test, example_gen_params), + KUNIT_CASE_PARAM_WITH_INIT(example_params_test_with_init, NULL, + example_param_init, NULL), KUNIT_CASE_SLOW(example_slow_test), {} };