[PATCH] kunit: reduce stack usage in kunit_run_tests()

From: Arnd Bergmann arnd@arndb.de

Some of the recent changes to the kunit framework caused the stack usage for kunit_run_tests() to grow higher than most other kernel functions, which triggers a warning when CONFIG_FRAME_WARN is set to a relatively low value:

lib/kunit/test.c: In function 'kunit_run_tests': lib/kunit/test.c:801:1: error: the frame size of 1312 bytes is larger than 1280 bytes [-Werror=frame-larger-than=]

Split out the inner loop into a separate function to ensure that each function remains under the limit, and pass the kunit_result_stats structures by reference to avoid excessive copies.

Signed-off-by: Arnd Bergmann arnd@arndb.de --- Sending it now as I ran into the build failure while testing 6.18. I only build-tested this, so please test it properly before applying. --- lib/kunit/test.c | 221 ++++++++++++++++++++++++----------------------- 1 file changed, 115 insertions(+), 106 deletions(-)

diff --git a/lib/kunit/test.c b/lib/kunit/test.c index 62eb529824c6..c5fce199d880 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -94,7 +94,7 @@ struct kunit_result_stats { unsigned long total; };

-static bool kunit_should_print_stats(struct kunit_result_stats stats) +static bool kunit_should_print_stats(struct kunit_result_stats *stats) { if (kunit_stats_enabled == 0) return false; @@ -102,11 +102,11 @@ static bool kunit_should_print_stats(struct kunit_result_stats stats) if (kunit_stats_enabled == 2) return true;

- return (stats.total > 1); + return (stats->total > 1); }

static void kunit_print_test_stats(struct kunit *test, - struct kunit_result_stats stats) + struct kunit_result_stats *stats) { if (!kunit_should_print_stats(stats)) return; @@ -115,10 +115,10 @@ static void kunit_print_test_stats(struct kunit *test, KUNIT_SUBTEST_INDENT "# %s: pass:%lu fail:%lu skip:%lu total:%lu", test->name, - stats.passed, - stats.failed, - stats.skipped, - stats.total); + stats->passed, + stats->failed, + stats->skipped, + stats->total); }

/* Append formatted message to log. */ @@ -600,26 +600,26 @@ static void kunit_run_case_catch_errors(struct kunit_suite *suite, }

static void kunit_print_suite_stats(struct kunit_suite *suite, - struct kunit_result_stats suite_stats, - struct kunit_result_stats param_stats) + struct kunit_result_stats *suite_stats, + struct kunit_result_stats *param_stats) { if (kunit_should_print_stats(suite_stats)) { kunit_log(KERN_INFO, suite, "# %s: pass:%lu fail:%lu skip:%lu total:%lu", suite->name, - suite_stats.passed, - suite_stats.failed, - suite_stats.skipped, - suite_stats.total); + suite_stats->passed, + suite_stats->failed, + suite_stats->skipped, + suite_stats->total); }

if (kunit_should_print_stats(param_stats)) { kunit_log(KERN_INFO, suite, "# Totals: pass:%lu fail:%lu skip:%lu total:%lu", - param_stats.passed, - param_stats.failed, - param_stats.skipped, - param_stats.total); + param_stats->passed, + param_stats->failed, + param_stats->skipped, + param_stats->total); } }

@@ -681,13 +681,106 @@ static void kunit_init_parent_param_test(struct kunit_case *test_case, struct ku } }

-int kunit_run_tests(struct kunit_suite *suite) +static int kunit_run_one_test(struct kunit_suite *suite, struct kunit_case *test_case, + struct kunit_result_stats *suite_stats, + struct kunit_result_stats *total_stats) { + struct kunit test = { .param_value = NULL, .param_index = 0 }; + struct kunit_result_stats param_stats = { 0 }; char param_desc[KUNIT_PARAM_DESC_SIZE]; + const void *curr_param; + + kunit_init_test(&test, test_case->name, test_case->log); + if (test_case->status == KUNIT_SKIPPED) { + /* Test marked as skip */ + test.status = KUNIT_SKIPPED; + kunit_update_stats(&param_stats, test.status); + } else if (!test_case->generate_params) { + /* Non-parameterised test. */ + test_case->status = KUNIT_SKIPPED; + kunit_run_case_catch_errors(suite, test_case, &test); + kunit_update_stats(&param_stats, test.status); + } else { + kunit_init_parent_param_test(test_case, &test); + if (test_case->status == KUNIT_FAILURE) { + kunit_update_stats(&param_stats, test.status); + goto test_case_end; + } + /* Get initial param. */ + param_desc[0] = '\0'; + /* TODO: Make generate_params try-catch */ + curr_param = test_case->generate_params(&test, NULL, param_desc); + test_case->status = KUNIT_SKIPPED; + kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT + "KTAP version 1\n"); + kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT + "# Subtest: %s", test_case->name); + if (test.params_array.params && + test_case->generate_params == kunit_array_gen_params) { + kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT + KUNIT_SUBTEST_INDENT "1..%zd\n", + test.params_array.num_params); + } + + while (curr_param) { + struct kunit param_test = { + .param_value = curr_param, + .param_index = ++test.param_index, + .parent = &test, + }; + kunit_init_test(&param_test, test_case->name, NULL); + param_test.log = test_case->log; + kunit_run_case_catch_errors(suite, test_case, &param_test); + + if (param_desc[0] == '\0') { + snprintf(param_desc, sizeof(param_desc), + "param-%d", param_test.param_index); + } + + kunit_print_ok_not_ok(&param_test, KUNIT_LEVEL_CASE_PARAM, + param_test.status, + param_test.param_index, + param_desc, + param_test.status_comment); + + kunit_update_stats(&param_stats, param_test.status); + + /* Get next param. */ + param_desc[0] = '\0'; + curr_param = test_case->generate_params(&test, curr_param, + param_desc); + } + /* + * TODO: Put into a try catch. Since we don't need suite->exit + * for it we can't reuse kunit_try_run_cleanup for this yet. + */ + if (test_case->param_exit) + test_case->param_exit(&test); + /* TODO: Put this kunit_cleanup into a try-catch. */ + kunit_cleanup(&test); + } +test_case_end: + kunit_print_attr((void *)test_case, true, KUNIT_LEVEL_CASE); + + kunit_print_test_stats(&test, &param_stats); + + kunit_print_ok_not_ok(&test, KUNIT_LEVEL_CASE, test_case->status, + kunit_test_case_num(suite, test_case), + test_case->name, + test.status_comment); + + kunit_update_stats(suite_stats, test_case->status); + kunit_accumulate_stats(total_stats, param_stats); + + return 0; +} + + +int kunit_run_tests(struct kunit_suite *suite) +{ struct kunit_case *test_case; struct kunit_result_stats suite_stats = { 0 }; struct kunit_result_stats total_stats = { 0 }; - const void *curr_param;

/* Taint the kernel so we know we've run tests. */ add_taint(TAINT_TEST, LOCKDEP_STILL_OK); @@ -703,97 +796,13 @@ int kunit_run_tests(struct kunit_suite *suite)

kunit_print_suite_start(suite);

- kunit_suite_for_each_test_case(suite, test_case) { - struct kunit test = { .param_value = NULL, .param_index = 0 }; - struct kunit_result_stats param_stats = { 0 }; - - kunit_init_test(&test, test_case->name, test_case->log); - if (test_case->status == KUNIT_SKIPPED) { - /* Test marked as skip */ - test.status = KUNIT_SKIPPED; - kunit_update_stats(&param_stats, test.status); - } else if (!test_case->generate_params) { - /* Non-parameterised test. */ - test_case->status = KUNIT_SKIPPED; - kunit_run_case_catch_errors(suite, test_case, &test); - kunit_update_stats(&param_stats, test.status); - } else { - kunit_init_parent_param_test(test_case, &test); - if (test_case->status == KUNIT_FAILURE) { - kunit_update_stats(&param_stats, test.status); - goto test_case_end; - } - /* Get initial param. */ - param_desc[0] = '\0'; - /* TODO: Make generate_params try-catch */ - curr_param = test_case->generate_params(&test, NULL, param_desc); - test_case->status = KUNIT_SKIPPED; - kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT - "KTAP version 1\n"); - kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT KUNIT_SUBTEST_INDENT - "# Subtest: %s", test_case->name); - if (test.params_array.params && - test_case->generate_params == kunit_array_gen_params) { - kunit_log(KERN_INFO, &test, KUNIT_SUBTEST_INDENT - KUNIT_SUBTEST_INDENT "1..%zd\n", - test.params_array.num_params); - } - - while (curr_param) { - struct kunit param_test = { - .param_value = curr_param, - .param_index = ++test.param_index, - .parent = &test, - }; - kunit_init_test(&param_test, test_case->name, NULL); - param_test.log = test_case->log; - kunit_run_case_catch_errors(suite, test_case, &param_test); - - if (param_desc[0] == '\0') { - snprintf(param_desc, sizeof(param_desc), - "param-%d", param_test.param_index); - } - - kunit_print_ok_not_ok(&param_test, KUNIT_LEVEL_CASE_PARAM, - param_test.status, - param_test.param_index, - param_desc, - param_test.status_comment); - - kunit_update_stats(&param_stats, param_test.status); - - /* Get next param. */ - param_desc[0] = '\0'; - curr_param = test_case->generate_params(&test, curr_param, - param_desc); - } - /* - * TODO: Put into a try catch. Since we don't need suite->exit - * for it we can't reuse kunit_try_run_cleanup for this yet. - */ - if (test_case->param_exit) - test_case->param_exit(&test); - /* TODO: Put this kunit_cleanup into a try-catch. */ - kunit_cleanup(&test); - } -test_case_end: - kunit_print_attr((void *)test_case, true, KUNIT_LEVEL_CASE); - - kunit_print_test_stats(&test, param_stats); - - kunit_print_ok_not_ok(&test, KUNIT_LEVEL_CASE, test_case->status, - kunit_test_case_num(suite, test_case), - test_case->name, - test.status_comment); - - kunit_update_stats(&suite_stats, test_case->status); - kunit_accumulate_stats(&total_stats, param_stats); - } + kunit_suite_for_each_test_case(suite, test_case) + kunit_run_one_test(suite, test_case, &suite_stats, &total_stats);

if (suite->suite_exit) suite->suite_exit(suite);

- kunit_print_suite_stats(suite, suite_stats, total_stats); + kunit_print_suite_stats(suite, &suite_stats, &total_stats); suite_end: kunit_print_suite_end(suite);