On Tue, Jul 29, 2025 at 3:37 PM Marie Zhussupova <marie...@google.com> wrote:
>
> KUnit parameterized tests currently support two
> primary methods for getting parameters:
> 1. Defining custom logic within a `generate_params`
> function.
> 2. Using the KUNIT_ARRAY_PARAM and KUNIT_ARRAY_PARAM_DESC
> macros with pre-defined static arrays.
>
> These methods present limitations when dealing with
> dynamically generated parameter arrays, or in scenarios
> where populating parameters sequentially via
> `generate_params` is inefficient or overly complex.
>
> This patch addresses these limitations by adding a new
> `params_data` field to `struct kunit`, of the type
> `kunit_params`. The struct `kunit_params` is designed to
> store the parameter array itself, along with essential metadata
> including the parameter count, parameter size, and a
> `get_description` function for providing custom descriptions
> for individual parameters.
>
> The `params_data` field can be populated by calling the new
> `kunit_register_params_array` macro from within a
> `param_init` function. By attaching the parameter array
> directly to the parent kunit test instance, these parameters
> can be iterated over in kunit_run_tests() behind the scenes.
>
> This modification provides greater flexibility to the
> KUnit framework, allowing testers to easily register and
> utilize both dynamic and static parameter arrays.
>
> Signed-off-by: Marie Zhussupova <marie...@google.com>
> ---
> include/kunit/test.h | 54 ++++++++++++++++++++++++++++++++++++++++----
> lib/kunit/test.c | 26 ++++++++++++++++++++-
> 2 files changed, 75 insertions(+), 5 deletions(-)
>
> diff --git a/include/kunit/test.h b/include/kunit/test.h
> index 4ba65dc35710..9143f0e22323 100644
> --- a/include/kunit/test.h
> +++ b/include/kunit/test.h
> @@ -245,7 +245,8 @@ static inline char *kunit_status_to_ok_not_ok(enum
> kunit_status status)
> */
> #define KUNIT_CASE_PARAM_WITH_INIT(test_name, gen_params, init, exit)
> \
> { .run_case = test_name, .name = #test_name,
> \
> - .generate_params = gen_params,
> \
> + .generate_params = (gen_params)
> \
> + ?: kunit_get_next_param_and_desc,
> \
> .param_init = init, .param_exit = exit,
> \
> .module_name = KBUILD_MODNAME}
>
> @@ -294,6 +295,21 @@ struct kunit_suite_set {
> struct kunit_suite * const *end;
> };
>
> +/* Stores the pointer to the parameter array and its metadata. */
> +struct kunit_params {
> + /*
> + * Reference to the parameter array for the parameterized tests. This
> + * is NULL if a parameter array wasn't directly passed to the
> + * parent kunit struct via the kunit_register_params_array macro.
> + */
> + const void *params;
> + /* Reference to a function that gets the description of a parameter.
> */
> + void (*get_description)(const void *param, char *desc);
> +
> + int num_params;
> + size_t elem_size;
> +};
> +
> /**
> * struct kunit - represents a running instance of a test.
> *
> @@ -302,12 +318,14 @@ struct kunit_suite_set {
> * @parent: for user to store data that they want to shared across
> * parameterized tests. Typically, the data is provided in
> * the param_init function (see &struct kunit_case).
> + * @params_data: for users to directly store the parameter array.
> *
> * Used to store information about the current context under which the test
> * is running. Most of this data is private and should only be accessed
> - * indirectly via public functions; the two exceptions are @priv and @parent
> - * which can be used by the test writer to store arbitrary data or data that
> is
> - * available to all parameter test executions, respectively.
> + * indirectly via public functions. There are three exceptions to this:
> @priv,
> + * @parent, and @params_data. These members can be used by the test writer to
> + * store arbitrary data, data available to all parameter test executions, and
> + * the parameter array, respectively.
> */
> struct kunit {
> void *priv;
> @@ -316,6 +334,8 @@ struct kunit {
> * during parameterized testing.
> */
> struct kunit *parent;
> + /* Stores the params array and all data related to it. */
> + struct kunit_params params_data;
>
> /* private: internal use only. */
> const char *name; /* Read only after initialization! */
> @@ -386,6 +406,8 @@ void kunit_exec_list_tests(struct kunit_suite_set
> *suite_set, bool include_attr)
> struct kunit_suite_set kunit_merge_suite_sets(struct kunit_suite_set
> init_suite_set,
> struct kunit_suite_set suite_set);
>
> +const void *kunit_get_next_param_and_desc(struct kunit *test, const void
> *prev, char *desc);
Hello!
Thanks for sending out this series! I will do a full review of it. For
now, I noticed that I get an error when I try to run KUnit tests as
modules. I get the following error: "ERROR: modpost:
"kunit_get_next_param_and_desc" [lib/kunit/kunit-example-test.ko]
undefined!". As a possible fix, I suggest moving the function
definition into the header file and making it a static inline
function.
Thanks!
-Rae
> +
> #if IS_BUILTIN(CONFIG_KUNIT)
> int kunit_run_all_tests(void);
> #else
> @@ -1735,6 +1757,30 @@ do {
> \
> return NULL;
> \
> }
>
> +/**
> + * kunit_register_params_array() - Register parameters for a KUnit test.
> + * @test: The KUnit test structure to which parameters will be added.
> + * @params_arr: An array of test parameters.
> + * @param_cnt: Number of parameters.
> + * @get_desc: A pointer to a function that generates a string description for
> + * a given parameter element.
> + *
> + * This macro initializes the @test's parameter array data, storing
> information
> + * including the parameter array, its count, the element size, and the
> parameter
> + * description function within `test->params_data`. KUnit's built-in
> + * `kunit_get_next_param_and_desc` function will automatically read this
> + * data when a custom `generate_params` function isn't provided.
> + */
> +#define kunit_register_params_array(test, params_arr, param_cnt, get_desc)
> \
> + do {
> \
> + struct kunit *_test = (test);
> \
> + const typeof((params_arr)[0]) * _params_ptr =
> &(params_arr)[0]; \
> + _test->params_data.params = _params_ptr;
> \
> + _test->params_data.num_params = (param_cnt);
> \
> + _test->params_data.elem_size = sizeof(*_params_ptr);
> \
> + _test->params_data.get_description = (get_desc);
> \
> + } while (0)
> +
> // TODO(dlaty...@google.com): consider eventually migrating users to
> explicitly
> // include resource.h themselves if they need it.
> #include <kunit/resource.h>
> diff --git a/lib/kunit/test.c b/lib/kunit/test.c
> index f50ef82179c4..2f4b7087db3f 100644
> --- a/lib/kunit/test.c
> +++ b/lib/kunit/test.c
> @@ -337,6 +337,13 @@ void __kunit_do_failed_assertion(struct kunit *test,
> }
> EXPORT_SYMBOL_GPL(__kunit_do_failed_assertion);
>
> +static void __kunit_init_params(struct kunit *test)
> +{
> + test->params_data.params = NULL;
> + test->params_data.num_params = 0;
> + test->params_data.elem_size = 0;
> +}
> +
> void kunit_init_test(struct kunit *test, const char *name, struct
> string_stream *log)
> {
> spin_lock_init(&test->lock);
> @@ -347,6 +354,7 @@ void kunit_init_test(struct kunit *test, const char
> *name, struct string_stream
> string_stream_clear(log);
> test->status = KUNIT_SUCCESS;
> test->status_comment[0] = '\0';
> + __kunit_init_params(test);
> }
> EXPORT_SYMBOL_GPL(kunit_init_test);
>
> @@ -641,6 +649,22 @@ static void kunit_accumulate_stats(struct
> kunit_result_stats *total,
> total->total += add.total;
> }
>
> +const void *kunit_get_next_param_and_desc(struct kunit *test, const void
> *prev, char *desc)
> +{
> + struct kunit_params *params_arr = &test->params_data;
> + const void *param;
> +
> + if (test->param_index < params_arr->num_params) {
> + param = (char *)params_arr->params
> + + test->param_index * params_arr->elem_size;
> +
> + if (params_arr->get_description)
> + params_arr->get_description(param, desc);
> + return param;
> + }
> + return NULL;
> +}
> +
> static void __kunit_init_parent_test(struct kunit_case *test_case, struct
> kunit *test)
> {
> if (test_case->param_init) {
> @@ -687,7 +711,7 @@ int kunit_run_tests(struct kunit_suite *suite)
> /* Test marked as skip */
> test.status = KUNIT_SKIPPED;
> kunit_update_stats(¶m_stats, test.status);
> - } else if (!test_case->generate_params) {
> + } else if (!test_case->generate_params &&
> !test.params_data.params) {
> /* Non-parameterised test. */
> test_case->status = KUNIT_SKIPPED;
> kunit_run_case_catch_errors(suite, test_case, &test);
> --
> 2.50.1.552.g942d659e1b-goog
>
