Hi Janusz,
On 2023-10-11 at 16:17:45 +0200, Janusz Krzysztofik wrote:
> Recent improvements to the kernel kunit framework allow us to obtain a
> list of test cases provided by a kunit test module without actually
> running them. Use that feature to get a list of expected test cases
> before we enter a loop around igt_dynamic(). Once done, enter the
> igt_dynamic() section for each consecutive test case immediately, even
> before first line of a related KTAP report appears, then look for a result
> from that test case. That should make our IGT results output still better
> synchronized with related kernel messages.
>
> The list of test cases provided by a kunit test module can be obtained by
> loading the kunit base module with specific options, then loading the test
> module. For that to be possible, take care of unloading the kunit base
> module before each kunit subtest (I was wrong when in one of my previous
> commit messages I suggested that on final unload of a kunit test module
> the kunit base module is unloaded automatically as its dependency,
> however, that didn't matter before, then no separate fix was required).
> Since that module can then be left loaded with non-default options if an
> error occurs, unload it explicitly before returning from igt_kunit().
>
> There are two possible ways of getting a list of test cases: by loading
> the base kunit module with action=list module option, or by filtering
> out all test cases from being executed while asking for SKIP results from
> those filtered out. Since the latter provides regular KTAP report that we
> can already parse perfectly, use it instead of trying to identify an
> unstructured list of test cases of unknown length submitted by the former.
>
> If an IGT test that calls igt_kunit() provides a subtest name then use
> that name to filter out potential test cases that don't belong to the
> named test suite from the list.
>
> To avoid loading any modules if no subtest is going to be executed (e.g.,
> if a nonexistent subtest has been requested), load the kunit modules in
> list mode from inside the igt_subtest_with_dynamic() section. In order to
> be free to skip the whole subtest on unmet requirements that need to be
> verified after that list has been already populated, clean it up from a
> follow up igt_fixture section.
>
> Since we may now finish processing of all test cases / dynamic sub-
> subtests before KTAP parsing completes, don't fail if we exit the loop of
> dynamic sub-subtests with -EINPROGRESS error code returned by the parser.
>
> v3: Preserve backward compatibility with kernels that can't provide
> listings of kunit test cases when kunit core is built as a module.
> v2: Split out changes in handling of modprobe errors and kernel taints to
> separate patches (Kamil),
> - fix some string duplicates referenced from filtered out test cases not
> freed,
> - don't check if next result is needed before fetching one, obviously
> true in first dynamic sub-subtest, and we always free last result
> before looping to next sub-subtest,
> - still break the loop of test cases on unexpected return codes from
> kunit_kmsg_get_result(),
> - use kunit_results_free() helper,
> - fix typos (Kamil),
> - update commit description.
>
> Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@xxxxxxxxxxxxxxx>
> Acked-by: Kamil Konieczny <kamil.konieczny@xxxxxxxxxxxxxxx> # v2
Reviewed-by: Kamil Konieczny <kamil.konieczny@xxxxxxxxxxxxxxx>
> ---
> lib/igt_kmod.c | 277 ++++++++++++++++++++++++++++++++++++++++++++++---
> 1 file changed, 264 insertions(+), 13 deletions(-)
>
> diff --git a/lib/igt_kmod.c b/lib/igt_kmod.c
> index 5d85732b08..c20c52d372 100644
> --- a/lib/igt_kmod.c
> +++ b/lib/igt_kmod.c
> @@ -902,8 +902,9 @@ static void kunit_results_free(struct igt_list_head *results,
> free(*suite_name);
> }
>
> -static void
> -__igt_kunit(struct igt_ktest *tst, const char *name, const char *opts)
> +static void __igt_kunit_legacy(struct igt_ktest *tst,
> + const char *name,
> + const char *opts)
> {
> struct modprobe_data modprobe = { tst->kmod, opts, 0, pthread_self(), };
> char *suite_name = NULL, *case_name = NULL;
> @@ -912,13 +913,7 @@ __igt_kunit(struct igt_ktest *tst, const char *name, const char *opts)
> pthread_mutexattr_t attr;
> IGT_LIST_HEAD(results);
> unsigned long taints;
> - int flags, ret;
> -
> - igt_skip_on_f(tst->kmsg < 0, "Could not open /dev/kmsg\n");
> -
> - igt_skip_on((flags = fcntl(tst->kmsg, F_GETFL, 0), flags < 0));
> - igt_skip_on_f(fcntl(tst->kmsg, F_SETFL, flags & ~O_NONBLOCK) == -1,
> - "Could not set /dev/kmsg to blocking mode\n");
> + int ret;
>
> igt_skip_on(lseek(tst->kmsg, 0, SEEK_END) < 0);
>
> @@ -1041,6 +1036,232 @@ __igt_kunit(struct igt_ktest *tst, const char *name, const char *opts)
> igt_skip_on_f(ret, "KTAP parser failed\n");
> }
>
> +static void kunit_get_tests(struct igt_list_head *tests,
> + struct igt_ktest *tst,
> + const char *filter,
> + const char *opts)
> +{
> + char *suite_name = NULL, *case_name = NULL;
> + struct igt_ktap_result *r, *rn;
> + struct igt_ktap_results *ktap;
> + int flags, err;
> +
> + igt_skip_on_f(tst->kmsg < 0, "Could not open /dev/kmsg\n");
> +
> + igt_skip_on((flags = fcntl(tst->kmsg, F_GETFL, 0), flags < 0));
> + igt_skip_on_f(fcntl(tst->kmsg, F_SETFL, flags & ~O_NONBLOCK) == -1,
> + "Could not set /dev/kmsg to blocking mode\n");
> +
> + igt_skip_on(lseek(tst->kmsg, 0, SEEK_END) < 0);
> +
> + /*
> + * To get a list of test cases provided by a kunit test module, ask the
> + * generic kunit module to respond with SKIP result for each test found.
> + * We could also use action=list kunit parameter to get the listing,
> + * however, parsing a KTAP report -- something that we already can do
> + * perfectly -- seems to be more safe than extracting a test case list
> + * of unknown length from /dev/kmsg.
> + *
> + * TODO: drop the following workaround, which is required by LTS kernel
> + * v6.1 not capable of listing test cases when built as a module.
> + * If loading the kunit module with required parameters fails then
> + * assume that we are running on a kernel with missing test case listing
> + * capabilities. Dont's skip but just return with empty list of test
> + * cases, that should tell the caller to use a legacy method of
> + * iterating over KTAP results collected from blind execution of all
> + * Kunit test cases provided by a Kunit test module.
> + */
> + if (igt_debug_on(igt_kmod_load("kunit",
> + "filter=module=none filter_action=skip")))
> + return;
> +
> + igt_skip_on(modprobe(tst->kmod, opts));
> +
> + ktap = igt_ktap_alloc(tests);
> + igt_require(ktap);
> +
> + do
> + err = kunit_kmsg_result_get(tests, NULL, tst->kmsg, ktap);
> + while (err == -EINPROGRESS);
> +
> + igt_ktap_free(ktap);
> +
> + if (!err)
> + igt_list_for_each_entry_safe(r, rn, tests, link) {
> + if (igt_debug_on(r->code != IGT_EXIT_SKIP)) {
> + err = r->code ?: -EPROTO;
> + break;
> + }
> +
> + if (!filter)
> + continue;
> +
> + if (strcmp(r->suite_name, filter))
> + kunit_result_free(&r, &case_name, &suite_name);
> + }
> +
> + if (err) {
> + kunit_results_free(tests, &case_name, &suite_name);
> + } else {
> + free(suite_name);
> + free(case_name);
> + }
> +
> + igt_skip_on(kmod_module_remove_module(tst->kmod, KMOD_REMOVE_FORCE));
> + igt_skip_on(igt_kmod_unload("kunit", KMOD_REMOVE_FORCE));
> +
> + igt_skip_on_f(err,
> + "KTAP parser failed while getting a list of test cases\n");
> +}
> +
> +static void __igt_kunit(struct igt_ktest *tst,
> + const char *name,
> + const char *opts,
> + struct igt_list_head *tests)
> +{
> + struct modprobe_data modprobe = { tst->kmod, opts, 0, pthread_self(), };
> + char *suite_name = NULL, *case_name = NULL;
> + struct igt_ktap_result *t, *r = NULL;
> + struct igt_ktap_results *ktap;
> + pthread_mutexattr_t attr;
> + IGT_LIST_HEAD(results);
> + int ret = -EINPROGRESS;
> + unsigned long taints;
> +
> + igt_skip_on(lseek(tst->kmsg, 0, SEEK_END) < 0);
> +
> + igt_skip_on(pthread_mutexattr_init(&attr));
> + igt_skip_on(pthread_mutexattr_setrobust(&attr, PTHREAD_MUTEX_ROBUST));
> + igt_skip_on(pthread_mutex_init(&modprobe.lock, &attr));
> +
> + ktap = igt_ktap_alloc(&results);
> + igt_require(ktap);
> +
> + if (igt_debug_on(pthread_create(&modprobe.thread, NULL,
> + modprobe_task, &modprobe))) {
> + igt_ktap_free(ktap);
> + igt_skip("Failed to create a modprobe thread\n");
> + }
> +
> + igt_list_for_each_entry(t, tests, link) {
> + igt_dynamic_f("%s%s%s",
> + strcmp(t->suite_name, name) ? t->suite_name : "",
> + strcmp(t->suite_name, name) ? "-" : "",
> + t->case_name) {
> +
> + if (igt_list_empty(&results)) {
> + igt_assert_eq(ret, -EINPROGRESS);
> + ret = kunit_kmsg_result_get(&results, &modprobe,
> + tst->kmsg, ktap);
> + igt_fail_on(igt_list_empty(&results));
> + }
> +
> + r = igt_list_first_entry(&results, r, link);
> +
> + while (igt_debug_on_f(strcmp(r->suite_name, t->suite_name),
> + "suite_name expected: %s, got: %s\n",
> + t->suite_name, r->suite_name) ||
> + igt_debug_on_f(strcmp(r->case_name, t->case_name),
> + "case_name expected: %s, got: %s\n",
> + t->case_name, r->case_name) ||
> + r->code == IGT_EXIT_INVALID) {
> +
> + int code = r->code;
> +
> + kunit_result_free(&r, &suite_name, &case_name);
> + if (igt_list_empty(&results)) {
> + igt_assert_eq(ret, -EINPROGRESS);
> + ret = kunit_kmsg_result_get(&results,
> + &modprobe,
> + tst->kmsg,
> + ktap);
> + igt_fail_on(igt_list_empty(&results));
> + }
> +
> + r = igt_list_first_entry(&results, r, link);
> +
> + if (code != IGT_EXIT_INVALID)
> + continue;
> +
> + /* result from parametrized test case */
> + igt_fail_on_f(strcmp(r->suite_name, suite_name),
> + "suite_name expected: %s, got: %s\n",
> + suite_name, r->suite_name);
> + igt_fail_on_f(strcmp(r->case_name, case_name),
> + "case_name expected: %s, got: %s\n",
> + case_name, r->case_name);
> + }
> +
> + igt_assert_neq(r->code, IGT_EXIT_INVALID);
> +
> + if (r->msg && *r->msg) {
> + igt_skip_on_f(r->code == IGT_EXIT_SKIP,
> + "%s\n", r->msg);
> + igt_fail_on_f(r->code == IGT_EXIT_FAILURE,
> + "%s\n", r->msg);
> + igt_abort_on_f(r->code == IGT_EXIT_ABORT,
> + "%s\n", r->msg);
> + } else {
> + igt_skip_on(r->code == IGT_EXIT_SKIP);
> + igt_fail_on(r->code == IGT_EXIT_FAILURE);
> + if (r->code == IGT_EXIT_ABORT)
> + igt_fail(r->code);
> + }
> + igt_assert_eq(r->code, IGT_EXIT_SUCCESS);
> +
> + switch (pthread_mutex_lock(&modprobe.lock)) {
> + case 0:
> + igt_debug_on(pthread_mutex_unlock(&modprobe.lock));
> + break;
> + case EOWNERDEAD:
> + /* leave the mutex unrecoverable */
> + igt_debug_on(pthread_mutex_unlock(&modprobe.lock));
> + __attribute__ ((fallthrough));
> + case ENOTRECOVERABLE:
> + igt_assert_eq(modprobe.err, 0);
> + break;
> + default:
> + igt_debug("pthread_mutex_lock() failed\n");
> + break;
> + }
> +
> + igt_assert_eq(igt_kernel_tainted(&taints), 0);
> + }
> +
> + kunit_result_free(&r, &suite_name, &case_name);
> +
> + if (igt_debug_on(ret != -EINPROGRESS))
> + break;
> + }
> +
> + kunit_results_free(&results, &suite_name, &case_name);
> +
> + switch (pthread_mutex_lock(&modprobe.lock)) {
> + case 0:
> + igt_debug_on(pthread_cancel(modprobe.thread));
> + igt_debug_on(pthread_mutex_unlock(&modprobe.lock));
> + igt_debug_on(pthread_join(modprobe.thread, NULL));
> + break;
> + case EOWNERDEAD:
> + /* leave the mutex unrecoverable */
> + igt_debug_on(pthread_mutex_unlock(&modprobe.lock));
> + break;
> + case ENOTRECOVERABLE:
> + break;
> + default:
> + igt_debug("pthread_mutex_lock() failed\n");
> + igt_debug_on(pthread_join(modprobe.thread, NULL));
> + break;
> + }
> +
> + igt_ktap_free(ktap);
> +
> + igt_skip_on(modprobe.err);
> + igt_skip_on(igt_kernel_tainted(&taints));
> + if (ret != -EINPROGRESS)
> + igt_skip_on_f(ret, "KTAP parser failed\n");
> +}
> +
> /**
> * igt_kunit:
> * @module_name: the name of the module
> @@ -1052,7 +1273,8 @@ __igt_kunit(struct igt_ktest *tst, const char *name, const char *opts)
> void igt_kunit(const char *module_name, const char *name, const char *opts)
> {
> struct igt_ktest tst = { .kmsg = -1, };
> -
> + const char *filter = name;
> + IGT_LIST_HEAD(tests);
>
> /*
> * If the caller (an IGT test) provides no subtest name then we
> @@ -1077,6 +1299,17 @@ void igt_kunit(const char *module_name, const char *name, const char *opts)
>
> igt_skip_on(igt_ktest_init(&tst, module_name));
> igt_skip_on(igt_ktest_begin(&tst));
> +
> + /*
> + * Since we need to load kunit base module with specific
> + * options in order to get a list of test cases, make
> + * sure that the module is not loaded. However, since
> + * unload may fail if kunit base module is not loaded,
> + * ignore any failures, we'll fail later if still loaded.
> + */
> + igt_ignore_warn(igt_kmod_unload("kunit", KMOD_REMOVE_FORCE));
> +
> + igt_assert(igt_list_empty(&tests));
> }
>
> /*
> @@ -1086,11 +1319,29 @@ void igt_kunit(const char *module_name, const char *name, const char *opts)
> * proper namespace for dynamic subtests, with is required for CI
> * and for documentation.
> */
> - igt_subtest_with_dynamic(name)
> - __igt_kunit(&tst, name, opts);
> + igt_subtest_with_dynamic(name) {
> + kunit_get_tests(&tests, &tst, filter, opts);
> + /*
> + * TODO: drop the __igt_kunit() legacy processing path, required
> + * by kernels v6.1-v6.5 with DRM Kunit support but not
> + * capable of listing test cases when built as a module,
> + * as soon as no longer required by major Linux
> + * distributions, now usually based on LTS kernel v6.1.
> + */
> + if (igt_debug_on(igt_list_empty(&tests)))
> + __igt_kunit_legacy(&tst, name, opts);
> + else
> + __igt_kunit(&tst, name, opts, &tests);
> + }
> +
> + igt_fixture {
> + char *suite_name = NULL, *case_name = NULL;
> +
> + kunit_results_free(&tests, &suite_name, &case_name);
>
> - igt_fixture
> igt_ktest_end(&tst);
> + igt_debug_on(igt_kmod_unload("kunit", KMOD_REMOVE_FORCE));
> + }
>
> igt_ktest_fini(&tst);
> }
> --
> 2.42.0
>
