Context: It's difficult to map a given .kunitconfig => set of enabled tests. Letting kunit.py figure that out would be useful.

This patch: * is intended to be an implementation detail used only by kunit.py * adds a kunit.action module param with one valid non-null value, "list" * for the "list" action, it simply prints out "<suite>.<test>" * leaves the kunit.py changes to make use of this for another patch.

Note: kunit.filter_glob is respected for this and all future actions.

Hack: we print a TAP header and fake test plan to allow kunit.py to use the same code to pick up KUnit output that it does for normal tests. Since this is intended to be an implementation detail, it seems fine for now. Maybe in the future we ouptut each test as SKIPPED or the like.

Go with a more generic "action" param, since it seems like we might eventually have more modes besides just running or listing tests, e.g. * perhaps a benchmark mode that reruns test cases and reports timing * perhaps a deflake mode that reruns test cases that failed * perhaps a mode where we randomize test order to try and catch hermeticity bugs like "test a only passes if run after test b"

Tested: $ ./tools/testing/kunit/kunit.py run --kernel_arg=kunit.action=list --raw_output=kunit ... TAP version 14 1..1 example.example_simple_test example.example_skip_test example.example_mark_skipped_test reboot: System halted

Signed-off-by: Daniel Latypov dlatypov@google.com --- lib/kunit/executor.c | 38 +++++++++++++++++++++++++++++++++----- 1 file changed, 33 insertions(+), 5 deletions(-)

diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c index 50aa73ebe0e6..4a3dd7c05245 100644 --- a/lib/kunit/executor.c +++ b/lib/kunit/executor.c @@ -202,9 +202,35 @@ static void kunit_print_tap_header(struct suite_set *suite_set) pr_info("1..%d\n", num_of_suites); }

-int kunit_run_all_tests(void) +static void kunit_exec_run_tests(struct suite_set *suite_set) +{ + struct kunit_suite * const * const *suites; + + kunit_print_tap_header(suite_set); + + for (suites = suite_set->start; suites < suite_set->end; suites++) + __kunit_test_suites_init(*suites); +} + +static void kunit_exec_list_tests(struct suite_set *suite_set) { + unsigned int i; struct kunit_suite * const * const *suites; + struct kunit_case *test_case; + + /* Hack: print a tap header so kunit.py can find the start of KUnit output. */ + kunit_print_tap_header(suite_set); + + for (suites = suite_set->start; suites < suite_set->end; suites++) + for (i = 0; (*suites)[i] != NULL; i++) { + kunit_suite_for_each_test_case((*suites)[i], test_case) { + pr_info("%s.%s\n", (*suites)[i]->name, test_case->name); + } + } +} + +int kunit_run_all_tests(void) +{ struct suite_set suite_set = { .start = __kunit_suites_start, .end = __kunit_suites_end, @@ -213,10 +239,12 @@ int kunit_run_all_tests(void) if (filter_glob_param) suite_set = kunit_filter_suites(&suite_set, filter_glob_param);

- kunit_print_tap_header(&suite_set); - - for (suites = suite_set.start; suites < suite_set.end; suites++) - __kunit_test_suites_init(*suites); + if (!action_param) + kunit_exec_run_tests(&suite_set); + else if (strcmp(action_param, "list") == 0) + kunit_exec_list_tests(&suite_set); + else + pr_err("kunit executor: unknown action '%s'\n", action_param);

if (filter_glob_param) { /* a copy was made of each array */ kunit_free_suite_set(suite_set);

The new --run_isolated flag makes the tool boot the kernel once per suite or test, preventing leftover state from one suite to impact the other. This can be useful as a starting point to debugging test hermeticity issues.

Note: it takes a lot longer, so people should not use it normally.

Consider the following very simplified example:

bool disable_something_for_test = false; void function_being_tested() { ... if (disable_something_for_test) return; ... }

static void test_before(struct kunit *test) { disable_something_for_test = true; function_being_tested(); /* oops, we forgot to reset it back to false */ }

static void test_after(struct kunit *test) { /* oops, now "fixing" test_before can cause test_after to fail! */ function_being_tested(); }

Presented like this, the issues are obvious, but it gets a lot more complicated to track down as the amount of test setup and helper functions increases.

Another use case is memory corruption. It might not be surface as an failure/crash in the test case or suite that caused it. I've noticed in kunit's own unit tests, the 3rd suite after might be the one to finally crash after an out-of-bounds write, for example.

Example usage:

Per suite: $ ./tools/testing/kunit/kunit.py run --kunitconfig=lib/kunit --run_isolated=suite ... Starting KUnit Kernel (1/7)... ============================================================ ======== [PASSED] kunit_executor_test ======== .... Testing complete. 5 tests run. 0 failed. 0 crashed. 0 skipped. Starting KUnit Kernel (2/7)... ============================================================ ======== [PASSED] kunit-try-catch-test ======== ...

Per test: $ ./tools/testing/kunit/kunit.py run --kunitconfig=lib/kunit --run_isolated=test Starting KUnit Kernel (1/23)... ============================================================ ======== [PASSED] kunit_executor_test ======== [PASSED] parse_filter_test ============================================================ Testing complete. 1 tests run. 0 failed. 0 crashed. 0 skipped. Starting KUnit Kernel (2/23)... ============================================================ ======== [PASSED] kunit_executor_test ======== [PASSED] filter_subsuite_test ...

It works with filters as well: $ ./tools/testing/kunit/kunit.py run --kunitconfig=lib/kunit --run_isolated=suite example ... Starting KUnit Kernel (1/1)... ============================================================ ======== [PASSED] example ======== ...

It also handles test filters, '*.*skip*' runs these 3 tests: kunit_status.kunit_status_mark_skipped_test example.example_skip_test example.example_mark_skipped_test

Signed-off-by: Daniel Latypov dlatypov@google.com --- tools/testing/kunit/kunit.py | 91 ++++++++++++++++++++------ tools/testing/kunit/kunit_tool_test.py | 40 +++++++++++ 2 files changed, 112 insertions(+), 19 deletions(-)

diff --git a/tools/testing/kunit/kunit.py b/tools/testing/kunit/kunit.py index 55c25f7a715c..060655d60533 100755 --- a/tools/testing/kunit/kunit.py +++ b/tools/testing/kunit/kunit.py @@ -16,7 +16,7 @@ assert sys.version_info >= (3, 7), "Python version is too old"

from collections import namedtuple from enum import Enum, auto -from typing import Iterable +from typing import Iterable, List

import kunit_config import kunit_json @@ -31,13 +31,13 @@ KunitBuildRequest = namedtuple('KunitBuildRequest', ['jobs', 'build_dir', 'alltests', 'make_options']) KunitExecRequest = namedtuple('KunitExecRequest', - ['timeout', 'build_dir', 'alltests', - 'filter_glob', 'kernel_args']) + ['timeout', 'build_dir', 'alltests', + 'filter_glob', 'kernel_args', 'run_isolated']) KunitParseRequest = namedtuple('KunitParseRequest', ['raw_output', 'build_dir', 'json']) KunitRequest = namedtuple('KunitRequest', ['raw_output','timeout', 'jobs', 'build_dir', 'alltests', 'filter_glob', - 'kernel_args', 'json', 'make_options']) + 'kernel_args', 'run_isolated', 'json', 'make_options'])

KernelDirectoryPath = sys.argv[0].split('tools/testing/kunit/')[0]

@@ -91,21 +91,66 @@ def build_tests(linux: kunit_kernel.LinuxSourceTree, 'built kernel successfully', build_end - build_start)

-def exec_tests(linux: kunit_kernel.LinuxSourceTree, request: KunitExecRequest, - parse_request: KunitParseRequest) -> KunitResult: - kunit_parser.print_with_timestamp('Starting KUnit Kernel ...') - test_start = time.time() - run_result = linux.run_kernel( - args=request.kernel_args, - timeout=None if request.alltests else request.timeout, - filter_glob=request.filter_glob, - build_dir=request.build_dir) +def _list_tests(linux: kunit_kernel.LinuxSourceTree, request: KunitExecRequest) -> List[str]: + args = ['kunit.action=list'] + if request.kernel_args: + args.extend(request.kernel_args) + + output = linux.run_kernel(args=args, + timeout=None if request.alltests else request.timeout, + filter_glob=request.filter_glob, + build_dir=request.build_dir) + output = kunit_parser.extract_tap_lines(output) + # Hack! Drop the TAP version header and top-level test plan. + output.pop() + output.pop() + return list(output) + +def _suites_from_test_list(tests: List[str]) -> List[str]: + """Extracts all the suites from an ordered list of tests.""" + suites = [] # type: List[str] + for t in tests: + parts = t.split('.', maxsplit=2) + if len(parts) != 2: + raise ValueError(f'internal KUnit error, test name should be of the form "<suite>.<test>", got "{t}"') + suite, case = parts + if not suites or suites[-1] != suite: + suites.append(suite) + return suites +

- test_end = time.time() - exec_time = test_end - test_start

- # Named tuples are immutable, so we rebuild them here manually - result = parse_tests(parse_request, run_result) +def exec_tests(linux: kunit_kernel.LinuxSourceTree, request: KunitExecRequest, + parse_request: KunitParseRequest) -> KunitResult: + filter_globs = [request.filter_glob] + if request.run_isolated: + tests = _list_tests(linux, request) + if request.run_isolated == 'test': + filter_globs = tests + if request.run_isolated == 'suite': + filter_globs = _suites_from_test_list(tests) + # Apply the test-part of the user's glob, if present. + if '.' in request.filter_glob: + test_glob = request.filter_glob.split('.', maxsplit=2)[1] + filter_globs = [g + '.'+ test_glob for g in filter_globs] + + overall_status = kunit_parser.TestStatus.SUCCESS + exec_time = 0 + for i, filter_glob in enumerate(filter_globs): + kunit_parser.print_with_timestamp('Starting KUnit Kernel ({}/{})...'.format(i+1, len(filter_globs))) + + test_start = time.time() + run_result = linux.run_kernel( + args=request.kernel_args, + timeout=None if request.alltests else request.timeout, + filter_glob=filter_glob, + build_dir=request.build_dir) + + test_end = time.time() + exec_time += test_end - test_start + + result = parse_tests(parse_request, run_result) + overall_status = kunit_parser.max_status(overall_status, result.status)

return KunitResult(status=result.status, result=result.result, elapsed_time=exec_time)

@@ -166,7 +211,7 @@ def run_tests(linux: kunit_kernel.LinuxSourceTree,

exec_request = KunitExecRequest(request.timeout, request.build_dir, request.alltests, request.filter_glob, - request.kernel_args) + request.kernel_args, request.run_isolated) parse_request = KunitParseRequest(request.raw_output, request.build_dir, request.json) @@ -251,6 +296,12 @@ def add_exec_opts(parser) -> None: parser.add_argument('--kernel_args', help='Kernel command-line parameters. Maybe be repeated', action='append') + parser.add_argument('--run_isolated', help='If set, boot the kernel for each ' + 'individual suite/test. This is can be useful for debugging ' + 'a non-hermetic test, one that might pass/fail based on ' + 'what ran before it.', + type=str, + choices=['suite', 'test']),

def add_parse_opts(parser) -> None: parser.add_argument('--raw_output', help='If set don't format output from kernel. ' @@ -324,6 +375,7 @@ def main(argv, linux=None): cli_args.alltests, cli_args.filter_glob, cli_args.kernel_args, + cli_args.run_isolated, cli_args.json, cli_args.make_options) result = run_tests(linux, request) @@ -379,7 +431,8 @@ def main(argv, linux=None): cli_args.build_dir, cli_args.alltests, cli_args.filter_glob, - cli_args.kernel_args) + cli_args.kernel_args, + cli_args.run_isolated) parse_request = KunitParseRequest(cli_args.raw_output, cli_args.build_dir, cli_args.json) diff --git a/tools/testing/kunit/kunit_tool_test.py b/tools/testing/kunit/kunit_tool_test.py index 619c4554cbff..bcfdc6664c9d 100755 --- a/tools/testing/kunit/kunit_tool_test.py +++ b/tools/testing/kunit/kunit_tool_test.py @@ -477,6 +477,46 @@ class KUnitMainTest(unittest.TestCase): args=['a=1','b=2'], build_dir='.kunit', filter_glob='', timeout=300) self.print_mock.assert_any_call(StrContains('Testing complete.'))

+ def test_list_tests(self): + want = ['suite.test1', 'suite.test2', 'suite2.test1'] + self.linux_source_mock.run_kernel.return_value = ['TAP version 14', '1..0'] + want + + got = kunit._list_tests(self.linux_source_mock, + kunit.KunitExecRequest(300, '.kunit', False, 'suite*', None, 'suite')) + + self.assertEqual(got, want) + # Should respect the user's filter glob when listing tests. + self.linux_source_mock.run_kernel.assert_called_once_with( + args=['kunit.action=list'], build_dir='.kunit', filter_glob='suite*', timeout=300) + + + @mock.patch.object(kunit, '_list_tests') + def test_run_isolated_by_suite(self, mock_tests): + mock_tests.return_value = ['suite.test1', 'suite.test2', 'suite2.test1'] + kunit.main(['exec', '--run_isolated=suite', 'suite*.test*'], self.linux_source_mock) + + # Should respect the user's filter glob when listing tests. + mock_tests.assert_called_once_with(mock.ANY, + kunit.KunitExecRequest(300, '.kunit', False, 'suite*.test*', None, 'suite')) + self.linux_source_mock.run_kernel.assert_has_calls([ + mock.call(args=None, build_dir='.kunit', filter_glob='suite.test*', timeout=300), + mock.call(args=None, build_dir='.kunit', filter_glob='suite2.test*', timeout=300), + ]) + + @mock.patch.object(kunit, '_list_tests') + def test_run_isolated_by_test(self, mock_tests): + mock_tests.return_value = ['suite.test1', 'suite.test2', 'suite2.test1'] + kunit.main(['exec', '--run_isolated=test', 'suite*'], self.linux_source_mock) + + # Should respect the user's filter glob when listing tests. + mock_tests.assert_called_once_with(mock.ANY, + kunit.KunitExecRequest(300, '.kunit', False, 'suite*', None, 'test')) + self.linux_source_mock.run_kernel.assert_has_calls([ + mock.call(args=None, build_dir='.kunit', filter_glob='suite.test1', timeout=300), + mock.call(args=None, build_dir='.kunit', filter_glob='suite.test2', timeout=300), + mock.call(args=None, build_dir='.kunit', filter_glob='suite2.test1', timeout=300), + ]) +

if __name__ == '__main__': unittest.main()