def _green_existing_locks():
"""Make locks created before monkey-patching safe.
RLocks rely on a Lock and on Python 2, if an unpatched Lock blocks, it
blocks the native thread. We need to replace these with green Locks.
This was originally noticed in the stdlib logging module."""
import gc
import threading
import eventlet.green.thread
lock_type = type(threading.Lock())
rlock_type = type(threading.RLock())
if sys.version_info[0] >= 3:
pyrlock_type = type(threading._PyRLock())
# We're monkey-patching so there can't be any greenlets yet, ergo our thread
# ID is the only valid owner possible.
tid = eventlet.green.thread.get_ident()
for obj in gc.get_objects():
if isinstance(obj, rlock_type):
if (sys.version_info[0] == 2 and
isinstance(obj._RLock__block, lock_type)):
_fix_py2_rlock(obj, tid)
elif (sys.version_info[0] >= 3 and
not isinstance(obj, pyrlock_type)):
_fix_py3_rlock(obj)
python类_PyRLock()的实例源码
def _green_existing_locks():
"""Make locks created before monkey-patching safe.
RLocks rely on a Lock and on Python 2, if an unpatched Lock blocks, it
blocks the native thread. We need to replace these with green Locks.
This was originally noticed in the stdlib logging module."""
import gc
import threading
import eventlet.green.thread
lock_type = type(threading.Lock())
rlock_type = type(threading.RLock())
if sys.version_info[0] >= 3:
pyrlock_type = type(threading._PyRLock())
# We're monkey-patching so there can't be any greenlets yet, ergo our thread
# ID is the only valid owner possible.
tid = eventlet.green.thread.get_ident()
for obj in gc.get_objects():
if isinstance(obj, rlock_type):
if (sys.version_info[0] == 2 and
isinstance(obj._RLock__block, lock_type)):
_fix_py2_rlock(obj, tid)
elif (sys.version_info[0] >= 3 and
not isinstance(obj, pyrlock_type)):
_fix_py3_rlock(obj)
def _fix_py3_rlock(old):
import gc
import threading
new = threading._PyRLock()
while old._is_owned():
old.release()
new.acquire()
if old._is_owned():
new.acquire()
gc.collect()
for ref in gc.get_referrers(old):
try:
ref_vars = vars(ref)
except TypeError:
pass
else:
for k, v in ref_vars.items():
if v == old:
setattr(ref, k, new)
def _fix_py3_rlock(old):
import gc
import threading
new = threading._PyRLock()
while old._is_owned():
old.release()
new.acquire()
if old._is_owned():
new.acquire()
gc.collect()
for ref in gc.get_referrers(old):
for k, v in vars(ref):
if v == old:
setattr(ref, k, new)
