Re: [PATCH v2 3/3] kunit: tool: support running each suite/test separately

On Wed, Sep 29, 2021 at 6:29 AM Daniel Latypov dlatypov@google.com wrote:

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

Nit: "might not be surfaced" or "might not surface"

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

Really glad to finally have this feature.

A few minor comments below (mostly mypy issues, though one of them seems to be a real bug). Otherwise, the main concern I have is that there's no final total of the tests run/passed/failed. That may be easier to implement post the parser rework patch, though, so I don't think we should hold this up for it: https://lore.kernel.org/linux-kselftest/20210901190623.315736-1-rmoar@google...

Also, if we changed the TAP header stuff in patch 1, there'd need to be a couple of minor changes here to support it.

Minor issues below aside, this is Reviewed-by: David Gow davidgow@google.com

Cheers, -- David

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 31eec9f6ecc3..e7b92caba53d 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)
  

mypy gives an error here: tools/testing/kunit/kunit.py:103: error: Incompatible types in assignment (expression has type "LineStream", variable has type "Iterator[str]") tools/testing/kunit/kunit.py:103: note: 'LineStream' is missing following 'Iterator' protocol member: tools/testing/kunit/kunit.py:103: note: __next__

•   # Hack! Drop the TAP version header and top-level test plan.
  

•   output.pop()
  

•   output.pop()
  

Similarly, mypy is complaining that: tools/testing/kunit/kunit.py:105: error: "Iterator[str]" has no attribute "pop" tools/testing/kunit/kunit.py:106: error: "Iterator[str]" has no attribute "pop"

Also, we could get rid of one of these output.pop() lines if we removed the test plan in Patch 1.

•   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
  

This doesn't seem to work. My test run, for example, gave: Elapsed time: 71.706s total, 0.001s configuring, 3.241s building, 0.001s running

The 0.001s running time seems way too small here.

Digging into this, it might be related to this mypy warning: tools/testing/kunit/kunit.py:150: error: Incompatible types in assignment (expression has type "float", variable has type "int")

Should it be exec_time = 0.0 or similar?

•   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)
  

@@ -250,6 +295,12 @@ 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. ' @@ -323,6 +374,7 @@ 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)
  

@@ -378,7 +430,8 @@ 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() -- 2.33.0.685.g46640cef36-goog