[Python-checkins] r87741 - in python/branches/release31-maint: Lib/threading.py

Tue Jan 4 19:42:29 CET 2011

Author: gregory.p.smith
Date: Tue Jan 4 19:42:29 2011
New Revision: 87741
Log:
Merged revisions 87740 via svnmerge from 
svn+ssh://pythondev@svn.python.org/python/branches/py3k
........
 r87740 | gregory.p.smith | 2011年01月04日 10:33:38 -0800 (2011年1月04日) | 6 lines
 
 Fix the new bug introduced in the r87710 fix for issue 6643. DummyThread
 deletes its _block attribute, deal with that. This prevents an uncaught
 exception in a thread during test_thread.
 
 This refactors a bit to better match what I did in the r87727 backport to 2.7.
........
Modified:
 python/branches/release31-maint/ (props changed)
 python/branches/release31-maint/Lib/threading.py
Modified: python/branches/release31-maint/Lib/threading.py
==============================================================================

--- python/branches/release31-maint/Lib/threading.py	(original)
+++ python/branches/release31-maint/Lib/threading.py	Tue Jan 4 19:42:29 2011
@@ -358,6 +358,10 @@
 self._cond = Condition(Lock())
 self._flag = False
 
+ def _reset_internal_locks(self):
+ # private! called by Thread._reset_internal_locks by _after_fork()
+ self._cond.__init__()
+
 def is_set(self):
 return self._flag
 
@@ -434,6 +438,13 @@
 # sys.exc_info since it can be changed between instances
 self._stderr = _sys.stderr
 
+ def _reset_internal_locks(self):
+ # private! Called by _after_fork() to reset our internal locks as
+ # they may be in an invalid state leading to a deadlock or crash.
+ if hasattr(self, '_block'): # DummyThread deletes _block
+ self._block.__init__()
+ self._started._reset_internal_locks()
+
 def _set_daemon(self):
 # Overridden in _MainThread and _DummyThread
 return current_thread().daemon
@@ -776,12 +787,11 @@
 def __init__(self):
 Thread.__init__(self, name=_newname("Dummy-%d"))
 
- # Thread.__block consumes an OS-level locking primitive, which
+ # Thread._block consumes an OS-level locking primitive, which
 # can never be used by a _DummyThread. Since a _DummyThread
 # instance is immortal, that's bad, so release this resource.
 del self._block
 
-
 self._started.set()
 self._set_ident()
 with _active_limbo_lock:
@@ -858,8 +868,7 @@
 thread._ident = ident
 # Any condition variables hanging off of the active thread may
 # be in an invalid state, so we reinitialize them.
- thread._block.__init__()
- thread._started._cond.__init__()
+ thread._reset_internal_locks()
 new_active[ident] = thread
 else:
 # All the others are already stopped.
