Introduce `example_params_test_with_init_dynamic_arr`. This new KUnit test demonstrates directly assigning a dynamic parameter array using the `kunit_register_params_array` macro. It highlights the use of `param_init` and `param_exit` for proper initialization and cleanup, and their registration to the test with `KUNIT_CASE_PARAM_WITH_INIT`.
Signed-off-by: Marie Zhussupova marievic@google.com --- lib/kunit/kunit-example-test.c | 95 ++++++++++++++++++++++++++++++++++ 1 file changed, 95 insertions(+)
diff --git a/lib/kunit/kunit-example-test.c b/lib/kunit/kunit-example-test.c index 5bf559e243f6..3ab121d81bf6 100644 --- a/lib/kunit/kunit-example-test.c +++ b/lib/kunit/kunit-example-test.c @@ -387,6 +387,98 @@ static void example_params_test_with_init(struct kunit *test) kunit_put_resource(res); }
+/* + * Helper function to create a parameter array of Fibonacci numbers. This example + * highlights a parameter generation scenario that is: + * 1. Not feasible to fully pre-generate at compile time. + * 2. Challenging to implement with a standard 'generate_params' function, + * as it typically only provides the immediately 'prev' parameter, while + * Fibonacci requires access to two preceding values for calculation. + */ +static void *make_fibonacci_params(int seq_size) +{ + int *seq; + + if (seq_size <= 0) + return NULL; + + seq = kmalloc_array(seq_size, sizeof(int), GFP_KERNEL); + + if (!seq) + return NULL; + + if (seq_size >= 1) + seq[0] = 0; + if (seq_size >= 2) + seq[1] = 1; + for (int i = 2; i < seq_size; i++) + seq[i] = seq[i - 1] + seq[i - 2]; + return seq; +} + +/* + * This is an example of a function that provides a description for each of the + * parameters. + */ +static void example_param_dynamic_arr_get_desc(const void *p, char *desc) +{ + const int *fib_num = p; + + snprintf(desc, KUNIT_PARAM_DESC_SIZE, "fibonacci param: %d", *fib_num); +} + +/* + * Example of a parameterized test init function that registers a dynamic array. + */ +static int example_param_init_dynamic_arr(struct kunit *test) +{ + int seq_size = 6; + int *fibonacci_params = make_fibonacci_params(seq_size); + + if (!fibonacci_params) + return -ENOMEM; + + /* + * Passes the dynamic parameter array information to the parent struct kunit. + * The array and its metadata will be stored in test->parent->params_data. + * The array itself will be located in params_data.params. + */ + kunit_register_params_array(test, fibonacci_params, seq_size, + example_param_dynamic_arr_get_desc); + return 0; +} + +/** + * Function to clean up the parameterized test's parent kunit struct if + * there were custom allocations. + */ +static void example_param_exit_dynamic_arr(struct kunit *test) +{ + /* + * We allocated this array, so we need to free it. + * Since the parent parameter instance is passed here, + * we can directly access the array via `test->params_data.params` + * instead of `test->parent->params_data.params`. + */ + kfree(test->params_data.params); +} + +/* + * Example of test that uses the registered dynamic array to perform assertions + * and expectations. + */ +static void example_params_test_with_init_dynamic_arr(struct kunit *test) +{ + const int *param = test->param_value; + int param_val; + + /* By design, param pointer will not be NULL. */ + KUNIT_ASSERT_NOT_NULL(test, param); + + param_val = *param; + KUNIT_EXPECT_EQ(test, param_val - param_val, 0); +} + /* * Here we make a list of all the test cases we want to add to the test suite * below. @@ -408,6 +500,9 @@ static struct kunit_case example_test_cases[] = { 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_PARAM_WITH_INIT(example_params_test_with_init_dynamic_arr, NULL, + example_param_init_dynamic_arr, + example_param_exit_dynamic_arr), KUNIT_CASE_SLOW(example_slow_test), {} };