From: Jérémie Galarneau Date: Thu, 15 Jun 2023 16:00:40 +0000 (-0400) Subject: Tests: introduce WaitTraceTestApplicationGroup X-Git-Url: https://git.liburcu.org/?p=lttng-tools.git;a=commitdiff_plain;h=c661f2f4c022314efcdc76b18f084cb42275370b Tests: introduce WaitTraceTestApplicationGroup A new test helper, WaitTraceTestApplicationGroup, is added to make it easier to write test that require a group of applications. A WaitTraceTestApplicationGroup can be used to: - launch a given number of applications, - make them trace (almost) all at once, - wait for the group of applications to complete Signed-off-by: Jérémie Galarneau Change-Id: I18023f1c507993a3e5647f87cd74ead3be392163 --- diff --git a/tests/utils/lttngtest/environment.py b/tests/utils/lttngtest/environment.py index c3d6e8262..4be5fb4fa 100644 --- a/tests/utils/lttngtest/environment.py +++ b/tests/utils/lttngtest/environment.py @@ -77,7 +77,7 @@ class _SignalWaitQueue: signal.signal(signal_number, original_handler) -class WaitTraceTestApplication: +class _WaitTraceTestApplication: """ Create an application that waits before tracing. This allows a test to launch an application, get its PID, and get it to start tracing when it @@ -90,6 +90,8 @@ class WaitTraceTestApplication: event_count, # type: int environment, # type: Environment wait_time_between_events_us=0, # type: int + wait_before_exit=False, # type: bool + wait_before_exit_file_path=None, # type: Optional[pathlib.Path] ): self._environment = environment # type: Environment self._iteration_count = event_count @@ -101,6 +103,24 @@ class WaitTraceTestApplication: dir=self._compat_open_path(environment.lttng_home_location), ) ) + # File that the application will create when all events have been emitted. + self._app_tracing_done_file_path = pathlib.Path( + tempfile.mktemp( + prefix="app_", + suffix="_done_tracing", + dir=self._compat_open_path(environment.lttng_home_location), + ) + ) + + if wait_before_exit and wait_before_exit_file_path is None: + wait_before_exit_file_path = pathlib.Path( + tempfile.mktemp( + prefix="app_", + suffix="_exit", + dir=self._compat_open_path(environment.lttng_home_location), + ) + ) + self._has_returned = False test_app_env = os.environ.copy() @@ -117,38 +137,46 @@ class WaitTraceTestApplication: ) # type: str test_app_args = [str(binary_path)] + test_app_args.extend(["--iter", str(event_count)]) test_app_args.extend( - shlex.split( - "--iter {iteration_count} --sync-application-in-main-touch {app_ready_file_path} --sync-before-first-event {app_start_tracing_file_path} --wait {wait_time_between_events_us}".format( - iteration_count=self._iteration_count, - app_ready_file_path=app_ready_file_path, - app_start_tracing_file_path=self._app_start_tracing_file_path, - wait_time_between_events_us=wait_time_between_events_us, - ) - ) + ["--sync-application-in-main-touch", str(app_ready_file_path)] + ) + test_app_args.extend( + ["--sync-before-first-event", str(self._app_start_tracing_file_path)] + ) + test_app_args.extend( + ["--sync-before-exit-touch", str(self._app_tracing_done_file_path)] ) + if wait_time_between_events_us != 0: + test_app_args.extend(["--wait", str(wait_time_between_events_us)]) self._process = subprocess.Popen( test_app_args, env=test_app_env, + stdout=subprocess.PIPE, + stderr=subprocess.STDOUT, ) # type: subprocess.Popen # Wait for the application to create the file indicating it has fully # initialized. Make sure the app hasn't crashed in order to not wait # forever. + self._wait_for_file_to_be_created(pathlib.Path(app_ready_file_path)) + + def _wait_for_file_to_be_created(self, sync_file_path): + # type: (pathlib.Path) -> None while True: - if os.path.exists(app_ready_file_path): + if os.path.exists(sync_file_path): break if self._process.poll() is not None: # Application has unexepectedly returned. raise RuntimeError( - "Test application has unexepectedly returned during its initialization with return code `{return_code}`".format( - return_code=self._process.returncode + "Test application has unexepectedly returned while waiting for synchronization file to be created: sync_file=`{sync_file}`, return_code=`{return_code}`".format( + sync_file=sync_file_path, return_code=self._process.returncode ) ) - time.sleep(0.1) + time.sleep(0.001) def trace(self): # type: () -> None @@ -161,6 +189,10 @@ class WaitTraceTestApplication: ) open(self._compat_open_path(self._app_start_tracing_file_path), mode="x") + def wait_for_tracing_done(self): + # type: () -> None + self._wait_for_file_to_be_created(self._app_tracing_done_file_path) + def wait_for_exit(self): # type: () -> None if self._process.wait() != 0: @@ -197,7 +229,84 @@ class WaitTraceTestApplication: self._process.wait() -class TraceTestApplication: +class WaitTraceTestApplicationGroup: + def __init__( + self, + environment, # type: Environment + application_count, # type: int + event_count, # type: int + wait_time_between_events_us=0, # type: int + wait_before_exit=False, # type: bool + ): + self._wait_before_exit_file_path = ( + pathlib.Path( + tempfile.mktemp( + prefix="app_group_", + suffix="_exit", + dir=_WaitTraceTestApplication._compat_open_path( + environment.lttng_home_location + ), + ) + ) + if wait_before_exit + else None + ) + + self._apps = [] + self._consumers = [] + for i in range(application_count): + new_app = environment.launch_wait_trace_test_application( + event_count, + wait_time_between_events_us, + wait_before_exit, + self._wait_before_exit_file_path, + ) + + # Attach an output consumer to log the application's error output (if any). + if environment._logging_function: + app_output_consumer = ProcessOutputConsumer( + new_app._process, + "app-{}".format(str(new_app.vpid)), + environment._logging_function, + ) # type: Optional[ProcessOutputConsumer] + app_output_consumer.daemon = True + app_output_consumer.start() + self._consumers.append(app_output_consumer) + + self._apps.append(new_app) + + def trace(self): + # type: () -> None + for app in self._apps: + app.trace() + + def exit( + self, wait_for_apps=False # type: bool + ): + if self._wait_before_exit_file_path is None: + raise RuntimeError( + "Can't call exit on an application group created with `wait_before_exit=False`" + ) + + # Wait for apps to have produced all of their events so that we can + # cause the death of all apps to happen within a short time span. + for app in self._apps: + app.wait_for_tracing_done() + + open( + _WaitTraceTestApplication._compat_open_path( + self._wait_before_exit_file_path + ), + mode="x", + ) + # Performed in two passes to allow tests to stress the unregistration of many applications. + # Waiting for each app to exit turn-by-turn would defeat the purpose here. + if wait_for_apps: + for app in self._apps: + app.wait_for_exit() + + +class _TraceTestApplication: """ Create an application that emits events as soon as it is launched. In most scenarios, it is preferable to use a WaitTraceTestApplication. @@ -407,12 +516,18 @@ class _Environment(logger._Logger): ) self._cleanup() - def launch_wait_trace_test_application(self, event_count): - # type: (int) -> WaitTraceTestApplication + def launch_wait_trace_test_application( + self, + event_count, # type: int + wait_time_between_events_us=0, + wait_before_exit=False, + wait_before_exit_file_path=None, + ): + # type: (int, int, bool, Optional[pathlib.Path]) -> _WaitTraceTestApplication """ Launch an application that will wait before tracing `event_count` events. """ - return WaitTraceTestApplication( + return _WaitTraceTestApplication( self._project_root / "tests" / "utils" @@ -421,6 +536,9 @@ class _Environment(logger._Logger): / "gen-ust-events", event_count, self, + wait_time_between_events_us, + wait_before_exit, + wait_before_exit_file_path, ) def launch_trace_test_constructor_application(self): @@ -428,7 +546,7 @@ class _Environment(logger._Logger): """ Launch an application that will trace from within constructors. """ - return TraceTestApplication( + return _TraceTestApplication( self._project_root / "tests" / "utils"