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			149 lines
		
	
	
	
		
			4.4 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			149 lines
		
	
	
	
		
			4.4 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| from test.test_importlib import util as test_util
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| 
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| init = test_util.import_importlib('importlib')
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| 
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| import sys
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| import threading
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| import unittest
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| import weakref
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| 
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| from test import support
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| from test.support import threading_helper
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| from test import lock_tests
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| 
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| 
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| class ModuleLockAsRLockTests:
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|     locktype = classmethod(lambda cls: cls.LockType("some_lock"))
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| 
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|     # _is_owned() unsupported
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|     test__is_owned = None
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|     # acquire(blocking=False) unsupported
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|     test_try_acquire = None
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|     test_try_acquire_contended = None
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|     # `with` unsupported
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|     test_with = None
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|     # acquire(timeout=...) unsupported
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|     test_timeout = None
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|     # _release_save() unsupported
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|     test_release_save_unacquired = None
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|     # lock status in repr unsupported
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|     test_repr = None
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|     test_locked_repr = None
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| 
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| LOCK_TYPES = {kind: splitinit._bootstrap._ModuleLock
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|               for kind, splitinit in init.items()}
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| 
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| (Frozen_ModuleLockAsRLockTests,
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|  Source_ModuleLockAsRLockTests
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|  ) = test_util.test_both(ModuleLockAsRLockTests, lock_tests.RLockTests,
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|                          LockType=LOCK_TYPES)
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| 
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| 
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| class DeadlockAvoidanceTests:
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| 
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|     def setUp(self):
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|         try:
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|             self.old_switchinterval = sys.getswitchinterval()
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|             support.setswitchinterval(0.000001)
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|         except AttributeError:
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|             self.old_switchinterval = None
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| 
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|     def tearDown(self):
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|         if self.old_switchinterval is not None:
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|             sys.setswitchinterval(self.old_switchinterval)
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| 
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|     def run_deadlock_avoidance_test(self, create_deadlock):
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|         NLOCKS = 10
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|         locks = [self.LockType(str(i)) for i in range(NLOCKS)]
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|         pairs = [(locks[i], locks[(i+1)%NLOCKS]) for i in range(NLOCKS)]
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|         if create_deadlock:
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|             NTHREADS = NLOCKS
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|         else:
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|             NTHREADS = NLOCKS - 1
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|         barrier = threading.Barrier(NTHREADS)
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|         results = []
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| 
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|         def _acquire(lock):
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|             """Try to acquire the lock. Return True on success,
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|             False on deadlock."""
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|             try:
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|                 lock.acquire()
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|             except self.DeadlockError:
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|                 return False
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|             else:
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|                 return True
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| 
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|         def f():
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|             a, b = pairs.pop()
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|             ra = _acquire(a)
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|             barrier.wait()
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|             rb = _acquire(b)
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|             results.append((ra, rb))
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|             if rb:
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|                 b.release()
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|             if ra:
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|                 a.release()
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|         lock_tests.Bunch(f, NTHREADS).wait_for_finished()
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|         self.assertEqual(len(results), NTHREADS)
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|         return results
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| 
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|     def test_deadlock(self):
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|         results = self.run_deadlock_avoidance_test(True)
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|         # At least one of the threads detected a potential deadlock on its
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|         # second acquire() call.  It may be several of them, because the
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|         # deadlock avoidance mechanism is conservative.
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|         nb_deadlocks = results.count((True, False))
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|         self.assertGreaterEqual(nb_deadlocks, 1)
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|         self.assertEqual(results.count((True, True)), len(results) - nb_deadlocks)
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| 
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|     def test_no_deadlock(self):
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|         results = self.run_deadlock_avoidance_test(False)
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|         self.assertEqual(results.count((True, False)), 0)
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|         self.assertEqual(results.count((True, True)), len(results))
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| 
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| 
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| DEADLOCK_ERRORS = {kind: splitinit._bootstrap._DeadlockError
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|                    for kind, splitinit in init.items()}
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| 
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| (Frozen_DeadlockAvoidanceTests,
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|  Source_DeadlockAvoidanceTests
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|  ) = test_util.test_both(DeadlockAvoidanceTests,
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|                          LockType=LOCK_TYPES,
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|                          DeadlockError=DEADLOCK_ERRORS)
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| 
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| 
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| class LifetimeTests:
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| 
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|     @property
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|     def bootstrap(self):
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|         return self.init._bootstrap
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| 
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|     def test_lock_lifetime(self):
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|         name = "xyzzy"
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|         self.assertNotIn(name, self.bootstrap._module_locks)
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|         lock = self.bootstrap._get_module_lock(name)
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|         self.assertIn(name, self.bootstrap._module_locks)
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|         wr = weakref.ref(lock)
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|         del lock
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|         support.gc_collect()
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|         self.assertNotIn(name, self.bootstrap._module_locks)
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|         self.assertIsNone(wr())
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| 
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|     def test_all_locks(self):
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|         support.gc_collect()
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|         self.assertEqual(0, len(self.bootstrap._module_locks),
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|                          self.bootstrap._module_locks)
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| 
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| 
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| (Frozen_LifetimeTests,
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|  Source_LifetimeTests
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|  ) = test_util.test_both(LifetimeTests, init=init)
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| 
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| 
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| def setUpModule():
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|     thread_info = threading_helper.threading_setup()
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|     unittest.addModuleCleanup(threading_helper.threading_cleanup, *thread_info)
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| 
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| 
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| if __name__ == '__main__':
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|     unittets.main()
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