Continue hacking the forkserver in Python 3.8

They got all fancy and added shared memory segment tracking and then
had to "generalize" the tracker name...hooray

Fixes #81
windows_support
Tyler Goodlet 2019-10-15 22:14:19 -04:00
parent 6ff32347bf
commit da4796749f
2 changed files with 53 additions and 20 deletions

View File

@ -15,7 +15,17 @@ import errno
import selectors import selectors
import warnings import warnings
from multiprocessing import semaphore_tracker, spawn, process # type: ignore try:
from multiprocessing import semaphore_tracker # type: ignore
resource_tracker = semaphore_tracker
resource_tracker._resource_tracker = resource_tracker._semaphore_tracker
_tracker_type = resource_tracker.SemaphoreTracker
except ImportError:
# 3.8 introduces a more general version that also tracks shared mems
from multiprocessing import resource_tracker # type: ignore
_tracker_type = resource_tracker.ResourceTracker
from multiprocessing import spawn, process # type: ignore
from multiprocessing import forkserver, util, connection # type: ignore from multiprocessing import forkserver, util, connection # type: ignore
from multiprocessing.forkserver import ( from multiprocessing.forkserver import (
ForkServer, MAXFDS_TO_SEND ForkServer, MAXFDS_TO_SEND
@ -48,7 +58,7 @@ class PatchedForkServer(ForkServer):
parent_r, child_w = os.pipe() parent_r, child_w = os.pipe()
child_r, parent_w = os.pipe() child_r, parent_w = os.pipe()
allfds = [child_r, child_w, self._forkserver_alive_fd, allfds = [child_r, child_w, self._forkserver_alive_fd,
semaphore_tracker.getfd()] resource_tracker.getfd()]
allfds += fds allfds += fds
# XXX This is the only part changed # XXX This is the only part changed
@ -83,7 +93,7 @@ class PatchedForkServer(ForkServer):
ensure_running() will do nothing. ensure_running() will do nothing.
''' '''
with self._lock: with self._lock:
semaphore_tracker.ensure_running() resource_tracker.ensure_running()
if self._forkserver_pid is not None: if self._forkserver_pid is not None:
# forkserver was launched before, is it still running? # forkserver was launched before, is it still running?
pid, status = os.waitpid(self._forkserver_pid, os.WNOHANG) pid, status = os.waitpid(self._forkserver_pid, os.WNOHANG)
@ -231,14 +241,14 @@ def main(listener_fd, alive_r, preload, main_path=None, sys_path=None):
# Incoming fork request # Incoming fork request
with listener.accept()[0] as s: with listener.accept()[0] as s:
# XXX Thing changed - be tolerant of socket disconnects # XXX Thing that changed - be tolerant of socket disconnects
try: try:
# Receive fds from client # Receive fds from client
fds = reduction.recvfds(s, MAXFDS_TO_SEND + 1) fds = reduction.recvfds(s, MAXFDS_TO_SEND + 1)
except EOFError: except EOFError:
# broken socket due to reconnection on client-side # broken socket due to reconnection on client-side
continue continue
# XXX Thing changed - be tolerant of socket disconnects # XXX Thing that changed - be tolerant of socket disconnects
if len(fds) > MAXFDS_TO_SEND: if len(fds) > MAXFDS_TO_SEND:
raise RuntimeError( raise RuntimeError(
@ -288,11 +298,19 @@ def _serve_one(child_r, fds, unused_fds, handlers):
for fd in unused_fds: for fd in unused_fds:
os.close(fd) os.close(fd)
# XXX this assigment is why we override this func...
(_forkserver._forkserver_alive_fd, (_forkserver._forkserver_alive_fd,
semaphore_tracker._semaphore_tracker._fd, resource_tracker._resource_tracker._fd,
*_forkserver._inherited_fds) = fds *_forkserver._inherited_fds) = fds
# Run process object received over pipe # Run process object received over pipe
# XXX this clearly changed
try:
# spawn._main() signature changed in 3.8
parent_sentinel = os.dup(child_r)
code = spawn._main(child_r, parent_sentinel)
except TypeError:
# pre 3.8 signature
code = spawn._main(child_r) code = spawn._main(child_r)
return code return code
@ -307,15 +325,16 @@ def write_signed(fd, n):
msg = msg[nbytes:] msg = msg[nbytes:]
class PatchedSemaphoreTracker(semaphore_tracker.SemaphoreTracker): class PatchedResourceTracker(_tracker_type): # type: ignore
"""Stop GD ensuring everything is running... """Stop GD ensuring everything is running...
""" """
def getfd(self): def getfd(self):
# XXX: why must be constantly spawn trackers..
# self.ensure_running() # self.ensure_running()
return self._fd return self._fd
_semaphore_tracker = PatchedSemaphoreTracker() _resource_tracker = PatchedResourceTracker()
_forkserver = PatchedForkServer() _forkserver = PatchedForkServer()
@ -328,11 +347,16 @@ def override_stdlib():
and semaphore trackers for each actor nursery used to create new and semaphore trackers for each actor nursery used to create new
sub-actors from sub-actors. sub-actors from sub-actors.
""" """
semaphore_tracker._semaphore_tracker = _semaphore_tracker try:
semaphore_tracker.ensure_running = _semaphore_tracker.ensure_running resource_tracker._semaphore_tracker = _resource_tracker
semaphore_tracker.register = _semaphore_tracker.register resource_tracker._resource_tracker = _resource_tracker
semaphore_tracker.unregister = _semaphore_tracker.unregister except AttributeError:
semaphore_tracker.getfd = _semaphore_tracker.getfd resource_tracker._resource_tracker = _resource_tracker
resource_tracker.ensure_running = _resource_tracker.ensure_running
resource_tracker.register = _resource_tracker.register
resource_tracker.unregister = _resource_tracker.unregister
resource_tracker.getfd = _resource_tracker.getfd
forkserver._forkserver = _forkserver forkserver._forkserver = _forkserver
forkserver.ensure_running = _forkserver.ensure_running forkserver.ensure_running = _forkserver.ensure_running

View File

@ -4,8 +4,17 @@ Process spawning.
Mostly just wrapping around ``multiprocessing``. Mostly just wrapping around ``multiprocessing``.
""" """
import multiprocessing as mp import multiprocessing as mp
from multiprocessing import forkserver, semaphore_tracker # type: ignore
from typing import Tuple, Optional try:
from multiprocessing import semaphore_tracker # type: ignore
resource_tracker = semaphore_tracker
resource_tracker._resource_tracker = resource_tracker._semaphore_tracker
except ImportError:
# 3.8 introduces a more general version that also tracks shared mems
from multiprocessing import resource_tracker # type: ignore
from multiprocessing import forkserver # type: ignore
from typing import Tuple
from . import _forkserver_override from . import _forkserver_override
from ._state import current_actor from ._state import current_actor
@ -71,8 +80,8 @@ def new_proc(
fs._forkserver_address, fs._forkserver_address,
fs._forkserver_alive_fd, fs._forkserver_alive_fd,
getattr(fs, '_forkserver_pid', None), getattr(fs, '_forkserver_pid', None),
getattr(semaphore_tracker._semaphore_tracker, '_pid', None), getattr(resource_tracker._resource_tracker, '_pid', None),
semaphore_tracker._semaphore_tracker._fd, resource_tracker._resource_tracker._fd,
) )
else: else:
assert curr_actor._forkserver_info assert curr_actor._forkserver_info
@ -80,8 +89,8 @@ def new_proc(
fs._forkserver_address, fs._forkserver_address,
fs._forkserver_alive_fd, fs._forkserver_alive_fd,
fs._forkserver_pid, fs._forkserver_pid,
semaphore_tracker._semaphore_tracker._pid, resource_tracker._resource_tracker._pid,
semaphore_tracker._semaphore_tracker._fd, resource_tracker._resource_tracker._fd,
) = curr_actor._forkserver_info ) = curr_actor._forkserver_info
else: else:
fs_info = (None, None, None, None, None) fs_info = (None, None, None, None, None)