import collections import faulthandler import json import os import queue import signal import subprocess import sys import threading import time import traceback import types from test import support from test.libregrtest.runtest import ( runtest, INTERRUPTED, CHILD_ERROR, PROGRESS_MIN_TIME, format_test_result, TestResult, is_failed, TIMEOUT) from test.libregrtest.setup import setup_tests from test.libregrtest.utils import format_duration, print_warning # Display the running tests if nothing happened last N seconds PROGRESS_UPDATE = 30.0 # seconds assert PROGRESS_UPDATE >= PROGRESS_MIN_TIME # Kill the main process after 5 minutes. It is supposed to write an update # every PROGRESS_UPDATE seconds. Tolerate 5 minutes for Python slowest # buildbot workers. MAIN_PROCESS_TIMEOUT = 5 * 60.0 assert MAIN_PROCESS_TIMEOUT >= PROGRESS_UPDATE # Time to wait until a worker completes: should be immediate JOIN_TIMEOUT = 30.0 # seconds USE_PROCESS_GROUP = (hasattr(os, "setsid") and hasattr(os, "killpg")) def must_stop(result, ns): if result.result == INTERRUPTED: return True if ns.failfast and is_failed(result, ns): return True return False def parse_worker_args(worker_args): ns_dict, test_name = json.loads(worker_args) ns = types.SimpleNamespace(**ns_dict) return (ns, test_name) def run_test_in_subprocess(testname, ns): ns_dict = vars(ns) worker_args = (ns_dict, testname) worker_args = json.dumps(worker_args) cmd = [sys.executable, *support.args_from_interpreter_flags(), '-u', # Unbuffered stdout and stderr '-m', 'test.regrtest', '--worker-args', worker_args] # Running the child from the same working directory as regrtest's original # invocation ensures that TEMPDIR for the child is the same when # sysconfig.is_python_build() is true. See issue 15300. kw = {} if USE_PROCESS_GROUP: kw['start_new_session'] = True return subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, universal_newlines=True, close_fds=(os.name != 'nt'), cwd=support.SAVEDCWD, **kw) def run_tests_worker(ns, test_name): setup_tests(ns) result = runtest(ns, test_name) print() # Force a newline (just in case) # Serialize TestResult as list in JSON print(json.dumps(list(result)), flush=True) sys.exit(0) # We do not use a generator so multiple threads can call next(). class MultiprocessIterator: """A thread-safe iterator over tests for multiprocess mode.""" def __init__(self, tests_iter): self.lock = threading.Lock() self.tests_iter = tests_iter def __iter__(self): return self def __next__(self): with self.lock: if self.tests_iter is None: raise StopIteration return next(self.tests_iter) def stop(self): with self.lock: self.tests_iter = None MultiprocessResult = collections.namedtuple('MultiprocessResult', 'result stdout stderr error_msg') class ExitThread(Exception): pass class TestWorkerProcess(threading.Thread): def __init__(self, worker_id, runner): super().__init__() self.worker_id = worker_id self.pending = runner.pending self.output = runner.output self.ns = runner.ns self.timeout = runner.worker_timeout self.regrtest = runner.regrtest self.current_test_name = None self.start_time = None self._popen = None self._killed = False self._stopped = False def __repr__(self): info = [f'TestWorkerProcess #{self.worker_id}'] if self.is_alive(): info.append("running") else: info.append('stopped') test = self.current_test_name if test: info.append(f'test={test}') popen = self._popen if popen is not None: dt = time.monotonic() - self.start_time info.extend((f'pid={self._popen.pid}', f'time={format_duration(dt)}')) return '<%s>' % ' '.join(info) def _kill(self): popen = self._popen if popen is None: return if self._killed: return self._killed = True if USE_PROCESS_GROUP: what = f"{self} process group" else: what = f"{self}" print(f"Kill {what}", file=sys.stderr, flush=True) try: if USE_PROCESS_GROUP: os.killpg(popen.pid, signal.SIGKILL) else: popen.kill() except ProcessLookupError: # popen.kill(): the process completed, the TestWorkerProcess thread # read its exit status, but Popen.send_signal() read the returncode # just before Popen.wait() set returncode. pass except OSError as exc: print_warning(f"Failed to kill {what}: {exc!r}") def stop(self): # Method called from a different thread to stop this thread self._stopped = True self._kill() def mp_result_error(self, test_name, error_type, stdout='', stderr='', err_msg=None): test_time = time.monotonic() - self.start_time result = TestResult(test_name, error_type, test_time, None) return MultiprocessResult(result, stdout, stderr, err_msg) def _run_process(self, test_name): self.start_time = time.monotonic() self.current_test_name = test_name try: popen = run_test_in_subprocess(test_name, self.ns) self._killed = False self._popen = popen except: self.current_test_name = None raise try: if self._stopped: # If kill() has been called before self._popen is set, # self._popen is still running. Call again kill() # to ensure that the process is killed. self._kill() raise ExitThread try: stdout, stderr = popen.communicate(timeout=self.timeout) retcode = popen.returncode assert retcode is not None except subprocess.TimeoutExpired: if self._stopped: # kill() has been called: communicate() fails # on reading closed stdout/stderr raise ExitThread # On timeout, kill the process self._kill() # None means TIMEOUT for the caller retcode = None # bpo-38207: Don't attempt to call communicate() again: on it # can hang until all child processes using stdout and stderr # pipes completes. stdout = stderr = '' except OSError: if self._stopped: # kill() has been called: communicate() fails # on reading closed stdout/stderr raise ExitThread raise else: stdout = stdout.strip() stderr = stderr.rstrip() return (retcode, stdout, stderr) except: self._kill() raise finally: self._wait_completed() self._popen = None self.current_test_name = None def _runtest(self, test_name): retcode, stdout, stderr = self._run_process(test_name) if retcode is None: return self.mp_result_error(test_name, TIMEOUT, stdout, stderr) err_msg = None if retcode != 0: err_msg = "Exit code %s" % retcode else: stdout, _, result = stdout.rpartition("\n") stdout = stdout.rstrip() if not result: err_msg = "Failed to parse worker stdout" else: try: # deserialize run_tests_worker() output result = json.loads(result) result = TestResult(*result) except Exception as exc: err_msg = "Failed to parse worker JSON: %s" % exc if err_msg is not None: return self.mp_result_error(test_name, CHILD_ERROR, stdout, stderr, err_msg) return MultiprocessResult(result, stdout, stderr, err_msg) def run(self): while not self._stopped: try: try: test_name = next(self.pending) except StopIteration: break mp_result = self._runtest(test_name) self.output.put((False, mp_result)) if must_stop(mp_result.result, self.ns): break except ExitThread: break except BaseException: self.output.put((True, traceback.format_exc())) break def _wait_completed(self): popen = self._popen # stdout and stderr must be closed to ensure that communicate() # does not hang popen.stdout.close() popen.stderr.close() try: popen.wait(JOIN_TIMEOUT) except (subprocess.TimeoutExpired, OSError) as exc: print_warning(f"Failed to wait for {self} completion " f"(timeout={format_duration(JOIN_TIMEOUT)}): " f"{exc!r}") def wait_stopped(self, start_time): # bpo-38207: MultiprocessTestRunner.stop_workers() called self.stop() # which killed the process. Sometimes, killing the process from the # main thread does not interrupt popen.communicate() in # TestWorkerProcess thread. This loop with a timeout is a workaround # for that. # # Moreover, if this method fails to join the thread, it is likely # that Python will hang at exit while calling threading._shutdown() # which tries again to join the blocked thread. Regrtest.main() # uses EXIT_TIMEOUT to workaround this second bug. while True: # Write a message every second self.join(1.0) if not self.is_alive(): break dt = time.monotonic() - start_time self.regrtest.log(f"Waiting for {self} thread " f"for {format_duration(dt)}") if dt > JOIN_TIMEOUT: print_warning(f"Failed to join {self} in {format_duration(dt)}") break def get_running(workers): running = [] for worker in workers: current_test_name = worker.current_test_name if not current_test_name: continue dt = time.monotonic() - worker.start_time if dt >= PROGRESS_MIN_TIME: text = '%s (%s)' % (current_test_name, format_duration(dt)) running.append(text) return running class MultiprocessTestRunner: def __init__(self, regrtest): self.regrtest = regrtest self.log = self.regrtest.log self.ns = regrtest.ns self.output = queue.Queue() self.pending = MultiprocessIterator(self.regrtest.tests) if self.ns.timeout is not None: # Rely on faulthandler to kill a worker process. This timouet is # when faulthandler fails to kill a worker process. Give a maximum # of 5 minutes to faulthandler to kill the worker. self.worker_timeout = min(self.ns.timeout * 1.5, self.ns.timeout + 5 * 60) else: self.worker_timeout = None self.workers = None def start_workers(self): self.workers = [TestWorkerProcess(index, self) for index in range(1, self.ns.use_mp + 1)] msg = f"Run tests in parallel using {len(self.workers)} child processes" if self.ns.timeout: msg += (" (timeout: %s, worker timeout: %s)" % (format_duration(self.ns.timeout), format_duration(self.worker_timeout))) self.log(msg) for worker in self.workers: worker.start() def stop_workers(self): start_time = time.monotonic() for worker in self.workers: worker.stop() for worker in self.workers: worker.wait_stopped(start_time) def _get_result(self): if not any(worker.is_alive() for worker in self.workers): # all worker threads are done: consume pending results try: return self.output.get(timeout=0) except queue.Empty: return None use_faulthandler = (self.ns.timeout is not None) timeout = PROGRESS_UPDATE while True: if use_faulthandler: faulthandler.dump_traceback_later(MAIN_PROCESS_TIMEOUT, exit=True) # wait for a thread try: return self.output.get(timeout=timeout) except queue.Empty: pass # display progress running = get_running(self.workers) if running and not self.ns.pgo: self.log('running: %s' % ', '.join(running)) def display_result(self, mp_result): result = mp_result.result text = format_test_result(result) if mp_result.error_msg is not None: # CHILD_ERROR text += ' (%s)' % mp_result.error_msg elif (result.test_time >= PROGRESS_MIN_TIME and not self.ns.pgo): text += ' (%s)' % format_duration(result.test_time) running = get_running(self.workers) if running and not self.ns.pgo: text += ' -- running: %s' % ', '.join(running) self.regrtest.display_progress(self.test_index, text) def _process_result(self, item): if item[0]: # Thread got an exception format_exc = item[1] print_warning(f"regrtest worker thread failed: {format_exc}") return True self.test_index += 1 mp_result = item[1] self.regrtest.accumulate_result(mp_result.result) self.display_result(mp_result) if mp_result.stdout: print(mp_result.stdout, flush=True) if mp_result.stderr and not self.ns.pgo: print(mp_result.stderr, file=sys.stderr, flush=True) if must_stop(mp_result.result, self.ns): return True return False def run_tests(self): self.start_workers() self.test_index = 0 try: while True: item = self._get_result() if item is None: break stop = self._process_result(item) if stop: break except KeyboardInterrupt: print() self.regrtest.interrupted = True finally: if self.ns.timeout is not None: faulthandler.cancel_dump_traceback_later() # Always ensure that all worker processes are no longer # worker when we exit this function self.pending.stop() self.stop_workers() def run_tests_multiprocess(regrtest): MultiprocessTestRunner(regrtest).run_tests()