STINNER Victor added the comment: I created a new repository just for this issue: http://hg.python.org/sandbox/issue21645
I added a lot of debug. It looks like a race condition: the SIGCHLD signal is handled in a thread B (a C thread, not a Python), whereas the asyncio event loop is running in a thread A (the main thread, a Python thread). Debug of the test which blocks: --- PIPE: (7, 8) threads [<_MainThread(MainThread, started 34384933888)>] [pid 78351] _run_once: thread=34384933888 Execute <Handle Task._step() created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/tasks.py:74> [pid 78351] _run_once: thread=34384933888 Execute <Handle StreamReaderProtocol.connection_made(<_UnixReadPipeTransport fd=7 polling>) created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/unix_events.py:287> Execute <Handle Future._set_result_unless_cancelled(None) created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/unix_events.py:290> [pid 78351] _run_once: thread=34384933888 Execute <Handle Task._wakeup(<Future finished result=None>) created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/futures.py:239> Read pipe 7 connected: (<_UnixReadPipeTransport fd=7 polling>, <asyncio.streams.StreamReaderProtocol object at 0x806e257a8>) [pid 78351] _run_once: thread=34384933888 Execute <Handle _raise_stop_error(<Task finished coro=<BaseEventLoop.connect_read_pipe() done, defined at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_events.py:767> created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_events.py:258 result=(<_UnixReadPipeTransport fd=7 polling>, <asyncio.streams.StreamReaderProtocol object at 0x806e257a8>)>) at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_events.py:95 created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/futures.py:239> Execute <Handle _raise_stop_error(<Task finished coro=<BaseEventLoop.connect_read_pipe() done, defined at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_events.py:767> created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_events.py:258 result=(<_UnixReadPipeTransport fd=7 polling>, <asyncio.streams.StreamReaderProtocol object at 0x806e257a8>)>) at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_events.py:95 created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/futures.py:239>: FAIL! _StopError() add_signal_handler(Signals.SIGCHLD, <bound method SafeChildWatcher._sig_chld of <asyncio.unix_events.SafeChildWatcher object at 0x806e25810>>, ()) PY signal.signal(Signals.SIGCHLD) [pid 78351] _run_once: thread=34384933888 Execute <Handle Task._step() created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/tasks.py:74> execute program '/usr/home/buildbot/buildarea/custom.krah-freebsd/build/python' process '/usr/home/buildbot/buildarea/custom.krah-freebsd/build/python' created: pid 78390 execute program '/usr/home/buildbot/buildarea/custom.krah-freebsd/build/python': <_UnixSubprocessTransport pid=78390> [pid 78351] _run_once: thread=34384933888 Execute <Handle SubprocessStreamProtocol.connection_made(<_UnixSubprocessTransport pid=78390>) created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_subprocess.py:121> [pid 78351] _run_once: thread=34384933888 Execute <Handle Task._wakeup(<Future finished result=None>) created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/futures.py:239> [pid 78351] _run_once: thread=34384933888 Execute <Handle _raise_stop_error(<Task finished coro=<create_subprocess_exec() done, defined at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/subprocess.py:208> created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_events.py:258 result=<Process 78390>>) at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_events.py:95 created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/futures.py:239> Execute <Handle _raise_stop_error(<Task finished coro=<create_subprocess_exec() done, defined at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/subprocess.py:208> created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_events.py:258 result=<Process 78390>>) at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/base_events.py:95 created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/futures.py:239>: FAIL! _StopError() [pid 78351] _run_once: thread=34384933888 Execute <Handle Task._step() created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/tasks.py:74> [pid 78351] _run_once: thread=34384933888 select(None) (1) import (2) dump traceback select(None) -> [(SelectorKey(fileobj=7, fd=7, events=1, data=(<Handle _UnixReadPipeTransport._read_ready() created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/selector_events.py:183>, None)), 1)] poll took 25.964 ms: [(SelectorKey(fileobj=7, fd=7, events=1, data=(<Handle _UnixReadPipeTransport._read_ready() created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/selector_events.py:183>, None)), 1)] Execute <Handle _UnixReadPipeTransport._read_ready() created at /usr/home/buildbot/buildarea/custom.krah-freebsd/build/Lib/asyncio/selector_events.py:183> [pid 78351] _run_once: thread=34384933888 select(None) (3) write into 8 (4) close 8 (5) exit [pid=78351] main_thread=34384933888 [78351] C signal.signal(20) [78351] C signal_handler: sig_num=20, thread=34468857856 C signal_handler: trip signal (tripped=0) [78351] trip_signal(20) trip_signal(20); write() select(None) -> [(SelectorKey(fileobj=5, fd=5, events=1, data=(<Handle BaseSelectorEventLoop._read_from_self()>, None)), 1)] poll took 4.902 ms: [(SelectorKey(fileobj=5, fd=5, events=1, data=(<Handle BaseSelectorEventLoop._read_from_self()>, None)), 1)] Execute <Handle BaseSelectorEventLoop._read_from_self()> [thread=34384933888] _read_from_self _read_from_self -> b'\x14' [thread=34384933888] _read_from_self _read_from_self -> blocking, stop [pid 78351] _run_once: thread=34384933888 select(None) trip_signal(20); write() -> 1 [78351] Py_AddPendingCall(checksignals_witharg), thread=34468857856 --- ---------- _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue21645> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: https://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
