Add support for classic queries
[ganeti-local] / test / ganeti.locking_unittest.py
index 3a77bc0..2706a72 100755 (executable)
@@ -1,7 +1,7 @@
 #!/usr/bin/python
 #
 
-# Copyright (C) 2006, 2007 Google Inc.
+# Copyright (C) 2006, 2007, 2010 Google Inc.
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -16,7 +16,7 @@
 # You should have received a copy of the GNU General Public License
 # along with this program; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
-# 0.0510-1301, USA.
+# 02110-1301, USA.
 
 
 """Script for unittesting the locking module"""
@@ -27,14 +27,24 @@ import unittest
 import time
 import Queue
 import threading
+import random
+import gc
+import itertools
 
+from ganeti import constants
 from ganeti import locking
 from ganeti import errors
+from ganeti import utils
+from ganeti import compat
+from ganeti import objects
+from ganeti import query
+
+import testutils
 
 
 # This is used to test the ssynchronize decorator.
 # Since it's passed as input to a decorator it must be declared as a global.
-_decoratorlock = locking.SharedLock()
+_decoratorlock = locking.SharedLock("decorator lock")
 
 #: List for looping tests
 ITERATIONS = range(8)
@@ -48,6 +58,15 @@ def _Repeat(fn):
   return wrapper
 
 
+def SafeSleep(duration):
+  start = time.time()
+  while True:
+    delay = start + duration - time.time()
+    if delay <= 0.0:
+      break
+    time.sleep(delay)
+
+
 class _ThreadedTestCase(unittest.TestCase):
   """Test class that supports adding/waiting on threads"""
   def setUp(self):
@@ -70,17 +89,17 @@ class _ThreadedTestCase(unittest.TestCase):
     self.threads = []
 
 
-class TestPipeCondition(_ThreadedTestCase):
-  """_PipeCondition tests"""
+class _ConditionTestCase(_ThreadedTestCase):
+  """Common test case for conditions"""
 
-  def setUp(self):
+  def setUp(self, cls):
     _ThreadedTestCase.setUp(self)
     self.lock = threading.Lock()
-    self.cond = locking._PipeCondition(self.lock)
+    self.cond = cls(self.lock)
 
-  def testAcquireRelease(self):
-    self.assert_(not self.cond._is_owned())
-    self.assertRaises(RuntimeError, self.cond.wait)
+  def _testAcquireRelease(self):
+    self.assertFalse(self.cond._is_owned())
+    self.assertRaises(RuntimeError, self.cond.wait, None)
     self.assertRaises(RuntimeError, self.cond.notifyAll)
 
     self.cond.acquire()
@@ -89,38 +108,86 @@ class TestPipeCondition(_ThreadedTestCase):
     self.assert_(self.cond._is_owned())
     self.cond.release()
 
-    self.assert_(not self.cond._is_owned())
-    self.assertRaises(RuntimeError, self.cond.wait)
+    self.assertFalse(self.cond._is_owned())
+    self.assertRaises(RuntimeError, self.cond.wait, None)
     self.assertRaises(RuntimeError, self.cond.notifyAll)
 
-  def testNotification(self):
+  def _testNotification(self):
     def _NotifyAll():
+      self.done.put("NE")
       self.cond.acquire()
+      self.done.put("NA")
       self.cond.notifyAll()
+      self.done.put("NN")
       self.cond.release()
 
     self.cond.acquire()
     self._addThread(target=_NotifyAll)
-    self.cond.wait()
+    self.assertEqual(self.done.get(True, 1), "NE")
+    self.assertRaises(Queue.Empty, self.done.get_nowait)
+    self.cond.wait(None)
+    self.assertEqual(self.done.get(True, 1), "NA")
+    self.assertEqual(self.done.get(True, 1), "NN")
     self.assert_(self.cond._is_owned())
     self.cond.release()
-    self.assert_(not self.cond._is_owned())
+    self.assertFalse(self.cond._is_owned())
+
+
+class TestSingleNotifyPipeCondition(_ConditionTestCase):
+  """SingleNotifyPipeCondition tests"""
+
+  def setUp(self):
+    _ConditionTestCase.setUp(self, locking.SingleNotifyPipeCondition)
+
+  def testAcquireRelease(self):
+    self._testAcquireRelease()
+
+  def testNotification(self):
+    self._testNotification()
+
+  def testWaitReuse(self):
+    self.cond.acquire()
+    self.cond.wait(0)
+    self.cond.wait(0.1)
+    self.cond.release()
+
+  def testNoNotifyReuse(self):
+    self.cond.acquire()
+    self.cond.notifyAll()
+    self.assertRaises(RuntimeError, self.cond.wait, None)
+    self.assertRaises(RuntimeError, self.cond.notifyAll)
+    self.cond.release()
+
+
+class TestPipeCondition(_ConditionTestCase):
+  """PipeCondition tests"""
+
+  def setUp(self):
+    _ConditionTestCase.setUp(self, locking.PipeCondition)
+
+  def testAcquireRelease(self):
+    self._testAcquireRelease()
+
+  def testNotification(self):
+    self._testNotification()
 
   def _TestWait(self, fn):
-    self._addThread(target=fn)
-    self._addThread(target=fn)
-    self._addThread(target=fn)
+    threads = [
+      self._addThread(target=fn),
+      self._addThread(target=fn),
+      self._addThread(target=fn),
+      ]
 
     # Wait for threads to be waiting
-    self.assertEqual(self.done.get(True, 1), "A")
-    self.assertEqual(self.done.get(True, 1), "A")
-    self.assertEqual(self.done.get(True, 1), "A")
+    for _ in threads:
+      self.assertEqual(self.done.get(True, 1), "A")
 
     self.assertRaises(Queue.Empty, self.done.get_nowait)
 
     self.cond.acquire()
-    self.assertEqual(self.cond._nwaiters, 3)
-    # This new thread can"t acquire the lock, and thus call wait, before we
+    self.assertEqual(len(self.cond._waiters), 3)
+    self.assertEqual(self.cond._waiters, set(threads))
+    # This new thread can't acquire the lock, and thus call wait, before we
     # release it
     self._addThread(target=fn)
     self.cond.notifyAll()
@@ -153,7 +220,7 @@ class TestPipeCondition(_ThreadedTestCase):
     def _BlockingWait():
       self.cond.acquire()
       self.done.put("A")
-      self.cond.wait()
+      self.cond.wait(None)
       self.cond.release()
       self.done.put("W")
 
@@ -194,113 +261,33 @@ class TestPipeCondition(_ThreadedTestCase):
     self.assertRaises(Queue.Empty, self.done.get_nowait)
 
 
-class TestSingleActionPipeCondition(unittest.TestCase):
-  """_SingleActionPipeCondition tests"""
-
-  def setUp(self):
-    self.cond = locking._SingleActionPipeCondition()
-
-  def testInitialization(self):
-    self.assert_(self.cond._read_fd is not None)
-    self.assert_(self.cond._write_fd is not None)
-    self.assert_(self.cond._poller is not None)
-    self.assertEqual(self.cond._nwaiters, 0)
-
-  def testUsageCount(self):
-    self.cond.StartWaiting()
-    self.assert_(self.cond._read_fd is not None)
-    self.assert_(self.cond._write_fd is not None)
-    self.assert_(self.cond._poller is not None)
-    self.assertEqual(self.cond._nwaiters, 1)
-
-    # use again
-    self.cond.StartWaiting()
-    self.assertEqual(self.cond._nwaiters, 2)
-
-    # there is more than one user
-    self.assert_(not self.cond.DoneWaiting())
-    self.assert_(self.cond._read_fd is not None)
-    self.assert_(self.cond._write_fd is not None)
-    self.assert_(self.cond._poller is not None)
-    self.assertEqual(self.cond._nwaiters, 1)
-
-    self.assert_(self.cond.DoneWaiting())
-    self.assertEqual(self.cond._nwaiters, 0)
-    self.assert_(self.cond._read_fd is None)
-    self.assert_(self.cond._write_fd is None)
-    self.assert_(self.cond._poller is None)
-
-  def testNotify(self):
-    wait1 = self.cond.StartWaiting()
-    wait2 = self.cond.StartWaiting()
-
-    self.assert_(self.cond._read_fd is not None)
-    self.assert_(self.cond._write_fd is not None)
-    self.assert_(self.cond._poller is not None)
-
-    self.cond.notifyAll()
-
-    self.assert_(self.cond._read_fd is not None)
-    self.assert_(self.cond._write_fd is None)
-    self.assert_(self.cond._poller is not None)
-
-    self.assert_(not self.cond.DoneWaiting())
-
-    self.assert_(self.cond._read_fd is not None)
-    self.assert_(self.cond._write_fd is None)
-    self.assert_(self.cond._poller is not None)
-
-    self.assert_(self.cond.DoneWaiting())
-
-    self.assert_(self.cond._read_fd is None)
-    self.assert_(self.cond._write_fd is None)
-    self.assert_(self.cond._poller is None)
-
-  def testReusage(self):
-    self.cond.StartWaiting()
-    self.assert_(self.cond._read_fd is not None)
-    self.assert_(self.cond._write_fd is not None)
-    self.assert_(self.cond._poller is not None)
-
-    self.assert_(self.cond.DoneWaiting())
-
-    self.assertRaises(RuntimeError, self.cond.StartWaiting)
-    self.assert_(self.cond._read_fd is None)
-    self.assert_(self.cond._write_fd is None)
-    self.assert_(self.cond._poller is None)
-
-  def testNotifyTwice(self):
-    self.cond.notifyAll()
-    self.assertRaises(RuntimeError, self.cond.notifyAll)
-
-
 class TestSharedLock(_ThreadedTestCase):
   """SharedLock tests"""
 
   def setUp(self):
     _ThreadedTestCase.setUp(self)
-    self.sl = locking.SharedLock()
+    self.sl = locking.SharedLock("TestSharedLock")
 
   def testSequenceAndOwnership(self):
-    self.assert_(not self.sl._is_owned())
+    self.assertFalse(self.sl.is_owned())
     self.sl.acquire(shared=1)
-    self.assert_(self.sl._is_owned())
-    self.assert_(self.sl._is_owned(shared=1))
-    self.assert_(not self.sl._is_owned(shared=0))
+    self.assert_(self.sl.is_owned())
+    self.assert_(self.sl.is_owned(shared=1))
+    self.assertFalse(self.sl.is_owned(shared=0))
     self.sl.release()
-    self.assert_(not self.sl._is_owned())
+    self.assertFalse(self.sl.is_owned())
     self.sl.acquire()
-    self.assert_(self.sl._is_owned())
-    self.assert_(not self.sl._is_owned(shared=1))
-    self.assert_(self.sl._is_owned(shared=0))
+    self.assert_(self.sl.is_owned())
+    self.assertFalse(self.sl.is_owned(shared=1))
+    self.assert_(self.sl.is_owned(shared=0))
     self.sl.release()
-    self.assert_(not self.sl._is_owned())
+    self.assertFalse(self.sl.is_owned())
     self.sl.acquire(shared=1)
-    self.assert_(self.sl._is_owned())
-    self.assert_(self.sl._is_owned(shared=1))
-    self.assert_(not self.sl._is_owned(shared=0))
+    self.assert_(self.sl.is_owned())
+    self.assert_(self.sl.is_owned(shared=1))
+    self.assertFalse(self.sl.is_owned(shared=0))
     self.sl.release()
-    self.assert_(not self.sl._is_owned())
+    self.assertFalse(self.sl.is_owned())
 
   def testBooleanValue(self):
     # semaphores are supposed to return a true value on a successful acquire
@@ -373,7 +360,7 @@ class TestSharedLock(_ThreadedTestCase):
     self.sl.release()
     self._waitThreads()
     self.failUnlessEqual(self.done.get_nowait(), 'DEL')
-    self.sl = locking.SharedLock()
+    self.sl = locking.SharedLock(self.sl.name)
 
   @_Repeat
   def testExclusiveBlocksSharer(self):
@@ -401,7 +388,7 @@ class TestSharedLock(_ThreadedTestCase):
     self.sl.release()
     self._waitThreads()
     self.failUnlessEqual(self.done.get_nowait(), 'DEL')
-    self.sl = locking.SharedLock()
+    self.sl = locking.SharedLock(self.sl.name)
 
   @_Repeat
   def testWaitingExclusiveBlocksSharer(self):
@@ -446,7 +433,31 @@ class TestSharedLock(_ThreadedTestCase):
     self.assertRaises(errors.LockError, self.sl.delete)
 
   def testDeleteTimeout(self):
-    self.sl.delete(timeout=60)
+    self.assertTrue(self.sl.delete(timeout=60))
+
+  def testDeleteTimeoutFail(self):
+    ready = threading.Event()
+    finish = threading.Event()
+
+    def fn():
+      self.sl.acquire(shared=0)
+      ready.set()
+
+      finish.wait()
+      self.sl.release()
+
+    self._addThread(target=fn)
+    ready.wait()
+
+    # Test if deleting a lock owned in exclusive mode by another thread fails
+    # to delete when a timeout is used
+    self.assertFalse(self.sl.delete(timeout=0.02))
+
+    finish.set()
+    self._waitThreads()
+
+    self.assertTrue(self.sl.delete())
+    self.assertRaises(errors.LockError, self.sl.acquire)
 
   def testNoDeleteIfSharer(self):
     self.sl.acquire(shared=1)
@@ -464,7 +475,7 @@ class TestSharedLock(_ThreadedTestCase):
     # The threads who were pending return ERR
     for _ in range(4):
       self.assertEqual(self.done.get_nowait(), 'ERR')
-    self.sl = locking.SharedLock()
+    self.sl = locking.SharedLock(self.sl.name)
 
   @_Repeat
   def testDeletePendingDeleteExclusiveSharers(self):
@@ -480,32 +491,38 @@ class TestSharedLock(_ThreadedTestCase):
     self.assertEqual(self.done.get_nowait(), 'ERR')
     self.assertEqual(self.done.get_nowait(), 'ERR')
     self.assertEqual(self.done.get_nowait(), 'ERR')
-    self.sl = locking.SharedLock()
+    self.sl = locking.SharedLock(self.sl.name)
 
   @_Repeat
   def testExclusiveAcquireTimeout(self):
-    def _LockExclusive(wait):
-      self.sl.acquire(shared=0)
-      self.done.put("A: start sleep")
-      time.sleep(wait)
-      self.done.put("A: end sleep")
-      self.sl.release()
-
     for shared in [0, 1]:
-      # Start thread to hold lock for 20 ms
-      self._addThread(target=_LockExclusive, args=(20.0 / 1000.0, ))
+      on_queue = threading.Event()
+      release_exclusive = threading.Event()
+
+      def _LockExclusive():
+        self.sl.acquire(shared=0, test_notify=on_queue.set)
+        self.done.put("A: start wait")
+        release_exclusive.wait()
+        self.done.put("A: end wait")
+        self.sl.release()
+
+      # Start thread to hold lock in exclusive mode
+      self._addThread(target=_LockExclusive)
+
+      # Wait for wait to begin
+      self.assertEqual(self.done.get(timeout=60), "A: start wait")
 
-      # Wait for sleep to begin
-      self.assertEqual(self.done.get(), "A: start sleep")
+      # Wait up to 60s to get lock, but release exclusive lock as soon as we're
+      # on the queue
+      self.failUnless(self.sl.acquire(shared=shared, timeout=60,
+                                      test_notify=release_exclusive.set))
 
-      # Wait up to 100 ms to get lock
-      self.failUnless(self.sl.acquire(shared=shared, timeout=0.1))
       self.done.put("got 2nd")
       self.sl.release()
 
       self._waitThreads()
 
-      self.assertEqual(self.done.get_nowait(), "A: end sleep")
+      self.assertEqual(self.done.get_nowait(), "A: end wait")
       self.assertEqual(self.done.get_nowait(), "got 2nd")
       self.assertRaises(Queue.Empty, self.done.get_nowait)
 
@@ -520,7 +537,7 @@ class TestSharedLock(_ThreadedTestCase):
       self.sl.acquire()
 
       # Start shared acquires with timeout between 0 and 20 ms
-      for i in xrange(11):
+      for i in range(11):
         self._addThread(target=_AcquireWithTimeout,
                         args=(shared, i * 2.0 / 1000.0))
 
@@ -531,7 +548,7 @@ class TestSharedLock(_ThreadedTestCase):
       # Release lock
       self.sl.release()
 
-      for _ in xrange(11):
+      for _ in range(11):
         self.assertEqual(self.done.get_nowait(), "timeout")
 
       self.assertRaises(Queue.Empty, self.done.get_nowait)
@@ -541,44 +558,52 @@ class TestSharedLock(_ThreadedTestCase):
     # Tests whether shared acquires jump in front of exclusive acquires in the
     # queue.
 
-    # Get exclusive lock while we fill the queue
-    self.sl.acquire()
+    def _Acquire(shared, name, notify_ev, wait_ev):
+      if notify_ev:
+        notify_fn = notify_ev.set
+      else:
+        notify_fn = None
+
+      if wait_ev:
+        wait_ev.wait()
 
-    def _Acquire(shared, name):
-      if not self.sl.acquire(shared=shared):
+      if not self.sl.acquire(shared=shared, test_notify=notify_fn):
         return
 
       self.done.put(name)
       self.sl.release()
 
-    # Start shared acquires
-    for _ in xrange(5):
-      self._addThread(target=_Acquire, args=(1, "shared A"))
+    # Get exclusive lock while we fill the queue
+    self.sl.acquire()
 
-    # Start exclusive acquires
-    for _ in xrange(3):
-      self._addThread(target=_Acquire, args=(0, "exclusive B"))
+    shrcnt1 = 5
+    shrcnt2 = 7
+    shrcnt3 = 9
+    shrcnt4 = 2
 
-    # More shared acquires
-    for _ in xrange(5):
-      self._addThread(target=_Acquire, args=(1, "shared C"))
+    # Add acquires using threading.Event for synchronization. They'll be
+    # acquired exactly in the order defined in this list.
+    acquires = (shrcnt1 * [(1, "shared 1")] +
+                3 * [(0, "exclusive 1")] +
+                shrcnt2 * [(1, "shared 2")] +
+                shrcnt3 * [(1, "shared 3")] +
+                shrcnt4 * [(1, "shared 4")] +
+                3 * [(0, "exclusive 2")])
 
-    # More exclusive acquires
-    for _ in xrange(3):
-      self._addThread(target=_Acquire, args=(0, "exclusive D"))
+    ev_cur = None
+    ev_prev = None
+
+    for args in acquires:
+      ev_cur = threading.Event()
+      self._addThread(target=_Acquire, args=args + (ev_cur, ev_prev))
+      ev_prev = ev_cur
+
+    # Wait for last acquire to start
+    ev_prev.wait()
 
     # Expect 6 pending exclusive acquires and 1 for all shared acquires
-    # together. There's no way to wait for SharedLock.acquire to start
-    # its work. Hence the timeout of 2 seconds.
-    pending = 0
-    end_time = time.time() + 2.0
-    while time.time() < end_time:
-      pending = self.sl._count_pending()
-      self.assert_(pending >= 0 and pending <= 7)
-      if pending == 7:
-        break
-      time.sleep(0.05)
-    self.assertEqual(pending, 7)
+    # together
+    self.assertEqual(self.sl._count_pending(), 7)
 
     # Release exclusive lock and wait
     self.sl.release()
@@ -586,30 +611,145 @@ class TestSharedLock(_ThreadedTestCase):
     self._waitThreads()
 
     # Check sequence
-    shr_a = 0
-    shr_c = 0
-    for _ in xrange(10):
+    for _ in range(shrcnt1 + shrcnt2 + shrcnt3 + shrcnt4):
       # Shared locks aren't guaranteed to be notified in order, but they'll be
       # first
       tmp = self.done.get_nowait()
-      if tmp == "shared A":
-        shr_a += 1
-      elif tmp == "shared C":
-        shr_c += 1
-    self.assertEqual(shr_a, 5)
-    self.assertEqual(shr_c, 5)
+      if tmp == "shared 1":
+        shrcnt1 -= 1
+      elif tmp == "shared 2":
+        shrcnt2 -= 1
+      elif tmp == "shared 3":
+        shrcnt3 -= 1
+      elif tmp == "shared 4":
+        shrcnt4 -= 1
+    self.assertEqual(shrcnt1, 0)
+    self.assertEqual(shrcnt2, 0)
+    self.assertEqual(shrcnt3, 0)
+    self.assertEqual(shrcnt3, 0)
 
-    for _ in xrange(3):
-      self.assertEqual(self.done.get_nowait(), "exclusive B")
+    for _ in range(3):
+      self.assertEqual(self.done.get_nowait(), "exclusive 1")
 
-    for _ in xrange(3):
-      self.assertEqual(self.done.get_nowait(), "exclusive D")
+    for _ in range(3):
+      self.assertEqual(self.done.get_nowait(), "exclusive 2")
 
     self.assertRaises(Queue.Empty, self.done.get_nowait)
 
+  def testIllegalDowngrade(self):
+    # Not yet acquired
+    self.assertRaises(AssertionError, self.sl.downgrade)
+
+    # Acquire in shared mode, downgrade should be no-op
+    self.assertTrue(self.sl.acquire(shared=1))
+    self.assertTrue(self.sl.is_owned(shared=1))
+    self.assertTrue(self.sl.downgrade())
+    self.assertTrue(self.sl.is_owned(shared=1))
+    self.sl.release()
+
+  def testDowngrade(self):
+    self.assertTrue(self.sl.acquire())
+    self.assertTrue(self.sl.is_owned(shared=0))
+    self.assertTrue(self.sl.downgrade())
+    self.assertTrue(self.sl.is_owned(shared=1))
+    self.sl.release()
+
+  @_Repeat
+  def testDowngradeJumpsAheadOfExclusive(self):
+    def _KeepExclusive(ev_got, ev_downgrade, ev_release):
+      self.assertTrue(self.sl.acquire())
+      self.assertTrue(self.sl.is_owned(shared=0))
+      ev_got.set()
+      ev_downgrade.wait()
+      self.assertTrue(self.sl.is_owned(shared=0))
+      self.assertTrue(self.sl.downgrade())
+      self.assertTrue(self.sl.is_owned(shared=1))
+      ev_release.wait()
+      self.assertTrue(self.sl.is_owned(shared=1))
+      self.sl.release()
+
+    def _KeepExclusive2(ev_started, ev_release):
+      self.assertTrue(self.sl.acquire(test_notify=ev_started.set))
+      self.assertTrue(self.sl.is_owned(shared=0))
+      ev_release.wait()
+      self.assertTrue(self.sl.is_owned(shared=0))
+      self.sl.release()
+
+    def _KeepShared(ev_started, ev_got, ev_release):
+      self.assertTrue(self.sl.acquire(shared=1, test_notify=ev_started.set))
+      self.assertTrue(self.sl.is_owned(shared=1))
+      ev_got.set()
+      ev_release.wait()
+      self.assertTrue(self.sl.is_owned(shared=1))
+      self.sl.release()
+
+    # Acquire lock in exclusive mode
+    ev_got_excl1 = threading.Event()
+    ev_downgrade_excl1 = threading.Event()
+    ev_release_excl1 = threading.Event()
+    th_excl1 = self._addThread(target=_KeepExclusive,
+                               args=(ev_got_excl1, ev_downgrade_excl1,
+                                     ev_release_excl1))
+    ev_got_excl1.wait()
+
+    # Start a second exclusive acquire
+    ev_started_excl2 = threading.Event()
+    ev_release_excl2 = threading.Event()
+    th_excl2 = self._addThread(target=_KeepExclusive2,
+                               args=(ev_started_excl2, ev_release_excl2))
+    ev_started_excl2.wait()
+
+    # Start shared acquires, will jump ahead of second exclusive acquire when
+    # first exclusive acquire downgrades
+    ev_shared = [(threading.Event(), threading.Event()) for _ in range(5)]
+    ev_release_shared = threading.Event()
+
+    th_shared = [self._addThread(target=_KeepShared,
+                                 args=(ev_started, ev_got, ev_release_shared))
+                 for (ev_started, ev_got) in ev_shared]
+
+    # Wait for all shared acquires to start
+    for (ev, _) in ev_shared:
+      ev.wait()
+
+    # Check lock information
+    self.assertEqual(self.sl.GetLockInfo(set([query.LQ_MODE, query.LQ_OWNER])),
+                     [(self.sl.name, "exclusive", [th_excl1.getName()], None)])
+    [(_, _, _, pending), ] = self.sl.GetLockInfo(set([query.LQ_PENDING]))
+    self.assertEqual([(pendmode, sorted(waiting))
+                      for (pendmode, waiting) in pending],
+                     [("exclusive", [th_excl2.getName()]),
+                      ("shared", sorted(th.getName() for th in th_shared))])
+
+    # Shared acquires won't start until the exclusive lock is downgraded
+    ev_downgrade_excl1.set()
+
+    # Wait for all shared acquires to be successful
+    for (_, ev) in ev_shared:
+      ev.wait()
+
+    # Check lock information again
+    self.assertEqual(self.sl.GetLockInfo(set([query.LQ_MODE,
+                                              query.LQ_PENDING])),
+                     [(self.sl.name, "shared", None,
+                       [("exclusive", [th_excl2.getName()])])])
+    [(_, _, owner, _), ] = self.sl.GetLockInfo(set([query.LQ_OWNER]))
+    self.assertEqual(set(owner), set([th_excl1.getName()] +
+                                     [th.getName() for th in th_shared]))
+
+    ev_release_excl1.set()
+    ev_release_excl2.set()
+    ev_release_shared.set()
+
+    self._waitThreads()
+
+    self.assertEqual(self.sl.GetLockInfo(set([query.LQ_MODE, query.LQ_OWNER,
+                                              query.LQ_PENDING])),
+                     [(self.sl.name, None, None, [])])
+
   @_Repeat
   def testMixedAcquireTimeout(self):
-    sync = threading.Condition()
+    sync = threading.Event()
 
     def _AcquireShared(ev):
       if not self.sl.acquire(shared=1, timeout=None):
@@ -620,18 +760,14 @@ class TestSharedLock(_ThreadedTestCase):
       # Notify main thread
       ev.set()
 
-      # Wait for notification
-      sync.acquire()
-      try:
-        sync.wait()
-      finally:
-        sync.release()
+      # Wait for notification from main thread
+      sync.wait()
 
       # Release lock
       self.sl.release()
 
     acquires = []
-    for _ in xrange(3):
+    for _ in range(3):
       ev = threading.Event()
       self._addThread(target=_AcquireShared, args=(ev, ))
       acquires.append(ev)
@@ -646,7 +782,7 @@ class TestSharedLock(_ThreadedTestCase):
     self.failIf(self.sl.acquire(shared=0, timeout=0.02))
 
     # Acquire exclusive without timeout
-    exclsync = threading.Condition()
+    exclsync = threading.Event()
     exclev = threading.Event()
 
     def _AcquireExclusive():
@@ -658,11 +794,8 @@ class TestSharedLock(_ThreadedTestCase):
       # Notify main thread
       exclev.set()
 
-      exclsync.acquire()
-      try:
-        exclsync.wait()
-      finally:
-        exclsync.release()
+      # Wait for notification from main thread
+      exclsync.wait()
 
       self.sl.release()
 
@@ -672,11 +805,7 @@ class TestSharedLock(_ThreadedTestCase):
     self.failIf(self.sl.acquire(shared=0, timeout=0.02))
 
     # Make all shared holders release their locks
-    sync.acquire()
-    try:
-      sync.notifyAll()
-    finally:
-      sync.release()
+    sync.set()
 
     # Wait for exclusive acquire to succeed
     exclev.wait()
@@ -691,15 +820,11 @@ class TestSharedLock(_ThreadedTestCase):
         self.done.put("shared2")
         self.sl.release()
 
-    for _ in xrange(10):
+    for _ in range(10):
       self._addThread(target=_AcquireSharedSimple)
 
     # Tell exclusive lock to release
-    exclsync.acquire()
-    try:
-      exclsync.notifyAll()
-    finally:
-      exclsync.release()
+    exclsync.set()
 
     # Wait for everything to finish
     self._waitThreads()
@@ -707,16 +832,236 @@ class TestSharedLock(_ThreadedTestCase):
     self.assertEqual(self.sl._count_pending(), 0)
 
     # Check sequence
-    for _ in xrange(3):
+    for _ in range(3):
       self.assertEqual(self.done.get_nowait(), "shared")
 
     self.assertEqual(self.done.get_nowait(), "exclusive")
 
-    for _ in xrange(10):
+    for _ in range(10):
       self.assertEqual(self.done.get_nowait(), "shared2")
 
     self.assertRaises(Queue.Empty, self.done.get_nowait)
 
+  def testPriority(self):
+    # Acquire in exclusive mode
+    self.assert_(self.sl.acquire(shared=0))
+
+    # Queue acquires
+    def _Acquire(prev, next, shared, priority, result):
+      prev.wait()
+      self.sl.acquire(shared=shared, priority=priority, test_notify=next.set)
+      try:
+        self.done.put(result)
+      finally:
+        self.sl.release()
+
+    counter = itertools.count(0)
+    priorities = range(-20, 30)
+    first = threading.Event()
+    prev = first
+
+    # Data structure:
+    # {
+    #   priority:
+    #     [(shared/exclusive, set(acquire names), set(pending threads)),
+    #      (shared/exclusive, ...),
+    #      ...,
+    #     ],
+    # }
+    perprio = {}
+
+    # References shared acquire per priority in L{perprio}. Data structure:
+    # {
+    #   priority: (shared=1, set(acquire names), set(pending threads)),
+    # }
+    prioshared = {}
+
+    for seed in [4979, 9523, 14902, 32440]:
+      # Use a deterministic random generator
+      rnd = random.Random(seed)
+      for priority in [rnd.choice(priorities) for _ in range(30)]:
+        modes = [0, 1]
+        rnd.shuffle(modes)
+        for shared in modes:
+          # Unique name
+          acqname = "%s/shr=%s/prio=%s" % (counter.next(), shared, priority)
+
+          ev = threading.Event()
+          thread = self._addThread(target=_Acquire,
+                                   args=(prev, ev, shared, priority, acqname))
+          prev = ev
+
+          # Record expected aqcuire, see above for structure
+          data = (shared, set([acqname]), set([thread]))
+          priolist = perprio.setdefault(priority, [])
+          if shared:
+            priosh = prioshared.get(priority, None)
+            if priosh:
+              # Shared acquires are merged
+              for i, j in zip(priosh[1:], data[1:]):
+                i.update(j)
+              assert data[0] == priosh[0]
+            else:
+              prioshared[priority] = data
+              priolist.append(data)
+          else:
+            priolist.append(data)
+
+    # Start all acquires and wait for them
+    first.set()
+    prev.wait()
+
+    # Check lock information
+    self.assertEqual(self.sl.GetLockInfo(set()),
+                     [(self.sl.name, None, None, None)])
+    self.assertEqual(self.sl.GetLockInfo(set([query.LQ_MODE, query.LQ_OWNER])),
+                     [(self.sl.name, "exclusive",
+                       [threading.currentThread().getName()], None)])
+
+    self._VerifyPrioPending(self.sl.GetLockInfo(set([query.LQ_PENDING])),
+                            perprio)
+
+    # Let threads acquire the lock
+    self.sl.release()
+
+    # Wait for everything to finish
+    self._waitThreads()
+
+    self.assert_(self.sl._check_empty())
+
+    # Check acquires by priority
+    for acquires in [perprio[i] for i in sorted(perprio.keys())]:
+      for (_, names, _) in acquires:
+        # For shared acquires, the set will contain 1..n entries. For exclusive
+        # acquires only one.
+        while names:
+          names.remove(self.done.get_nowait())
+      self.assertFalse(compat.any(names for (_, names, _) in acquires))
+
+    self.assertRaises(Queue.Empty, self.done.get_nowait)
+
+  def _VerifyPrioPending(self, ((name, mode, owner, pending), ), perprio):
+    self.assertEqual(name, self.sl.name)
+    self.assert_(mode is None)
+    self.assert_(owner is None)
+
+    self.assertEqual([(pendmode, sorted(waiting))
+                      for (pendmode, waiting) in pending],
+                     [(["exclusive", "shared"][int(bool(shared))],
+                       sorted(t.getName() for t in threads))
+                      for acquires in [perprio[i]
+                                       for i in sorted(perprio.keys())]
+                      for (shared, _, threads) in acquires])
+
+  class _FakeTimeForSpuriousNotifications:
+    def __init__(self, now, check_end):
+      self.now = now
+      self.check_end = check_end
+
+      # Deterministic random number generator
+      self.rnd = random.Random(15086)
+
+    def time(self):
+      # Advance time if the random number generator thinks so (this is to test
+      # multiple notifications without advancing the time)
+      if self.rnd.random() < 0.3:
+        self.now += self.rnd.random()
+
+      self.check_end(self.now)
+
+      return self.now
+
+  @_Repeat
+  def testAcquireTimeoutWithSpuriousNotifications(self):
+    ready = threading.Event()
+    locked = threading.Event()
+    req = Queue.Queue(0)
+
+    epoch = 4000.0
+    timeout = 60.0
+
+    def check_end(now):
+      self.assertFalse(locked.isSet())
+
+      # If we waited long enough (in virtual time), tell main thread to release
+      # lock, otherwise tell it to notify once more
+      req.put(now < (epoch + (timeout * 0.8)))
+
+    time_fn = self._FakeTimeForSpuriousNotifications(epoch, check_end).time
+
+    sl = locking.SharedLock("test", _time_fn=time_fn)
+
+    # Acquire in exclusive mode
+    sl.acquire(shared=0)
+
+    def fn():
+      self.assertTrue(sl.acquire(shared=0, timeout=timeout,
+                                 test_notify=ready.set))
+      locked.set()
+      sl.release()
+      self.done.put("success")
+
+    # Start acquire with timeout and wait for it to be ready
+    self._addThread(target=fn)
+    ready.wait()
+
+    # The separate thread is now waiting to acquire the lock, so start sending
+    # spurious notifications.
+
+    # Wait for separate thread to ask for another notification
+    count = 0
+    while req.get():
+      # After sending the notification, the lock will take a short amount of
+      # time to notice and to retrieve the current time
+      sl._notify_topmost()
+      count += 1
+
+    self.assertTrue(count > 100, "Not enough notifications were sent")
+
+    self.assertFalse(locked.isSet())
+
+    # Some notifications have been sent, now actually release the lock
+    sl.release()
+
+    # Wait for lock to be acquired
+    locked.wait()
+
+    self._waitThreads()
+
+    self.assertEqual(self.done.get_nowait(), "success")
+    self.assertRaises(Queue.Empty, self.done.get_nowait)
+
+
+class TestSharedLockInCondition(_ThreadedTestCase):
+  """SharedLock as a condition lock tests"""
+
+  def setUp(self):
+    _ThreadedTestCase.setUp(self)
+    self.sl = locking.SharedLock("TestSharedLockInCondition")
+    self.setCondition()
+
+  def setCondition(self):
+    self.cond = threading.Condition(self.sl)
+
+  def testKeepMode(self):
+    self.cond.acquire(shared=1)
+    self.assert_(self.sl.is_owned(shared=1))
+    self.cond.wait(0)
+    self.assert_(self.sl.is_owned(shared=1))
+    self.cond.release()
+    self.cond.acquire(shared=0)
+    self.assert_(self.sl.is_owned(shared=0))
+    self.cond.wait(0)
+    self.assert_(self.sl.is_owned(shared=0))
+    self.cond.release()
+
+
+class TestSharedLockInPipeCondition(TestSharedLockInCondition):
+  """SharedLock as a pipe condition lock tests"""
+
+  def setCondition(self):
+    self.cond = locking.PipeCondition(self.sl)
+
 
 class TestSSynchronizedDecorator(_ThreadedTestCase):
   """Shared Lock Synchronized decorator test"""
@@ -726,19 +1071,19 @@ class TestSSynchronizedDecorator(_ThreadedTestCase):
 
   @locking.ssynchronized(_decoratorlock)
   def _doItExclusive(self):
-    self.assert_(_decoratorlock._is_owned())
+    self.assert_(_decoratorlock.is_owned())
     self.done.put('EXC')
 
   @locking.ssynchronized(_decoratorlock, shared=1)
   def _doItSharer(self):
-    self.assert_(_decoratorlock._is_owned(shared=1))
+    self.assert_(_decoratorlock.is_owned(shared=1))
     self.done.put('SHR')
 
   def testDecoratedFunctions(self):
     self._doItExclusive()
-    self.assert_(not _decoratorlock._is_owned())
+    self.assertFalse(_decoratorlock.is_owned())
     self._doItSharer()
-    self.assert_(not _decoratorlock._is_owned())
+    self.assertFalse(_decoratorlock.is_owned())
 
   def testSharersCanCoexist(self):
     _decoratorlock.acquire(shared=1)
@@ -785,34 +1130,68 @@ class TestLockSet(_ThreadedTestCase):
   def _setUpLS(self):
     """Helper to (re)initialize the lock set"""
     self.resources = ['one', 'two', 'three']
-    self.ls = locking.LockSet(members=self.resources)
+    self.ls = locking.LockSet(self.resources, "TestLockSet")
 
   def testResources(self):
     self.assertEquals(self.ls._names(), set(self.resources))
-    newls = locking.LockSet()
+    newls = locking.LockSet([], "TestLockSet.testResources")
     self.assertEquals(newls._names(), set())
 
+  def testCheckOwnedUnknown(self):
+    self.assertFalse(self.ls.check_owned("certainly-not-owning-this-one"))
+    for shared in [-1, 0, 1, 6378, 24255]:
+      self.assertFalse(self.ls.check_owned("certainly-not-owning-this-one",
+                                           shared=shared))
+
+  def testCheckOwnedUnknownWhileHolding(self):
+    self.assertFalse(self.ls.check_owned([]))
+    self.ls.acquire("one", shared=1)
+    self.assertRaises(errors.LockError, self.ls.check_owned, "nonexist")
+    self.assertTrue(self.ls.check_owned("one", shared=1))
+    self.assertFalse(self.ls.check_owned("one", shared=0))
+    self.assertFalse(self.ls.check_owned(["one", "two"]))
+    self.assertRaises(errors.LockError, self.ls.check_owned,
+                      ["one", "nonexist"])
+    self.assertRaises(errors.LockError, self.ls.check_owned, "")
+    self.ls.release()
+    self.assertFalse(self.ls.check_owned([]))
+    self.assertFalse(self.ls.check_owned("one"))
+
   def testAcquireRelease(self):
+    self.assertFalse(self.ls.check_owned(self.ls._names()))
     self.assert_(self.ls.acquire('one'))
-    self.assertEquals(self.ls._list_owned(), set(['one']))
+    self.assertEquals(self.ls.list_owned(), set(['one']))
+    self.assertTrue(self.ls.check_owned("one"))
+    self.assertTrue(self.ls.check_owned("one", shared=0))
+    self.assertFalse(self.ls.check_owned("one", shared=1))
     self.ls.release()
-    self.assertEquals(self.ls._list_owned(), set())
+    self.assertEquals(self.ls.list_owned(), set())
+    self.assertFalse(self.ls.check_owned(self.ls._names()))
     self.assertEquals(self.ls.acquire(['one']), set(['one']))
-    self.assertEquals(self.ls._list_owned(), set(['one']))
+    self.assertEquals(self.ls.list_owned(), set(['one']))
     self.ls.release()
-    self.assertEquals(self.ls._list_owned(), set())
+    self.assertEquals(self.ls.list_owned(), set())
     self.ls.acquire(['one', 'two', 'three'])
-    self.assertEquals(self.ls._list_owned(), set(['one', 'two', 'three']))
+    self.assertEquals(self.ls.list_owned(), set(['one', 'two', 'three']))
+    self.assertTrue(self.ls.check_owned(self.ls._names()))
+    self.assertTrue(self.ls.check_owned(self.ls._names(), shared=0))
+    self.assertFalse(self.ls.check_owned(self.ls._names(), shared=1))
     self.ls.release('one')
-    self.assertEquals(self.ls._list_owned(), set(['two', 'three']))
+    self.assertFalse(self.ls.check_owned(["one"]))
+    self.assertTrue(self.ls.check_owned(["two", "three"]))
+    self.assertTrue(self.ls.check_owned(["two", "three"], shared=0))
+    self.assertFalse(self.ls.check_owned(["two", "three"], shared=1))
+    self.assertEquals(self.ls.list_owned(), set(['two', 'three']))
     self.ls.release(['three'])
-    self.assertEquals(self.ls._list_owned(), set(['two']))
+    self.assertEquals(self.ls.list_owned(), set(['two']))
     self.ls.release()
-    self.assertEquals(self.ls._list_owned(), set())
+    self.assertEquals(self.ls.list_owned(), set())
     self.assertEquals(self.ls.acquire(['one', 'three']), set(['one', 'three']))
-    self.assertEquals(self.ls._list_owned(), set(['one', 'three']))
+    self.assertEquals(self.ls.list_owned(), set(['one', 'three']))
     self.ls.release()
-    self.assertEquals(self.ls._list_owned(), set())
+    self.assertEquals(self.ls.list_owned(), set())
+    for name in self.ls._names():
+      self.assertFalse(self.ls.check_owned(name))
 
   def testNoDoubleAcquire(self):
     self.ls.acquire('one')
@@ -832,31 +1211,31 @@ class TestLockSet(_ThreadedTestCase):
 
   def testAddRemove(self):
     self.ls.add('four')
-    self.assertEquals(self.ls._list_owned(), set())
+    self.assertEquals(self.ls.list_owned(), set())
     self.assert_('four' in self.ls._names())
     self.ls.add(['five', 'six', 'seven'], acquired=1)
     self.assert_('five' in self.ls._names())
     self.assert_('six' in self.ls._names())
     self.assert_('seven' in self.ls._names())
-    self.assertEquals(self.ls._list_owned(), set(['five', 'six', 'seven']))
+    self.assertEquals(self.ls.list_owned(), set(['five', 'six', 'seven']))
     self.assertEquals(self.ls.remove(['five', 'six']), ['five', 'six'])
     self.assert_('five' not in self.ls._names())
     self.assert_('six' not in self.ls._names())
-    self.assertEquals(self.ls._list_owned(), set(['seven']))
+    self.assertEquals(self.ls.list_owned(), set(['seven']))
     self.assertRaises(AssertionError, self.ls.add, 'eight', acquired=1)
     self.ls.remove('seven')
     self.assert_('seven' not in self.ls._names())
-    self.assertEquals(self.ls._list_owned(), set([]))
+    self.assertEquals(self.ls.list_owned(), set([]))
     self.ls.acquire(None, shared=1)
     self.assertRaises(AssertionError, self.ls.add, 'eight')
     self.ls.release()
     self.ls.acquire(None)
     self.ls.add('eight', acquired=1)
     self.assert_('eight' in self.ls._names())
-    self.assert_('eight' in self.ls._list_owned())
+    self.assert_('eight' in self.ls.list_owned())
     self.ls.add('nine')
     self.assert_('nine' in self.ls._names())
-    self.assert_('nine' not in self.ls._list_owned())
+    self.assert_('nine' not in self.ls.list_owned())
     self.ls.release()
     self.ls.remove(['two'])
     self.assert_('two' not in self.ls._names())
@@ -889,8 +1268,8 @@ class TestLockSet(_ThreadedTestCase):
   def testAcquireSetLock(self):
     # acquire the set-lock exclusively
     self.assertEquals(self.ls.acquire(None), set(['one', 'two', 'three']))
-    self.assertEquals(self.ls._list_owned(), set(['one', 'two', 'three']))
-    self.assertEquals(self.ls._is_owned(), True)
+    self.assertEquals(self.ls.list_owned(), set(['one', 'two', 'three']))
+    self.assertEquals(self.ls.is_owned(), True)
     self.assertEquals(self.ls._names(), set(['one', 'two', 'three']))
     # I can still add/remove elements...
     self.assertEquals(self.ls.remove(['two', 'three']), ['two', 'three'])
@@ -906,17 +1285,17 @@ class TestLockSet(_ThreadedTestCase):
     self.assertEquals(self.ls.acquire(['two', 'two', 'three'], shared=1),
                       set(['two', 'two', 'three']))
     self.ls.release(['two', 'two'])
-    self.assertEquals(self.ls._list_owned(), set(['three']))
+    self.assertEquals(self.ls.list_owned(), set(['three']))
 
   def testEmptyAcquire(self):
     # Acquire an empty list of locks...
     self.assertEquals(self.ls.acquire([]), set())
-    self.assertEquals(self.ls._list_owned(), set())
+    self.assertEquals(self.ls.list_owned(), set())
     # New locks can still be addded
     self.assert_(self.ls.add('six'))
     # "re-acquiring" is not an issue, since we had really acquired nothing
     self.assertEquals(self.ls.acquire([], shared=1), set())
-    self.assertEquals(self.ls._list_owned(), set())
+    self.assertEquals(self.ls.list_owned(), set())
     # We haven't really acquired anything, so we cannot release
     self.assertRaises(AssertionError, self.ls.release)
 
@@ -982,6 +1361,127 @@ class TestLockSet(_ThreadedTestCase):
       self.failUnlessEqual(self.done.get_nowait(), 'DONE')
 
   @_Repeat
+  def testSimpleAcquireTimeoutExpiring(self):
+    names = sorted(self.ls._names())
+    self.assert_(len(names) >= 3)
+
+    # Get name of first lock
+    first = names[0]
+
+    # Get name of last lock
+    last = names.pop()
+
+    checks = [
+      # Block first and try to lock it again
+      (first, first),
+
+      # Block last and try to lock all locks
+      (None, first),
+
+      # Block last and try to lock it again
+      (last, last),
+      ]
+
+    for (wanted, block) in checks:
+      # Lock in exclusive mode
+      self.assert_(self.ls.acquire(block, shared=0))
+
+      def _AcquireOne():
+        # Try to get the same lock again with a timeout (should never succeed)
+        acquired = self.ls.acquire(wanted, timeout=0.1, shared=0)
+        if acquired:
+          self.done.put("acquired")
+          self.ls.release()
+        else:
+          self.assert_(acquired is None)
+          self.assertFalse(self.ls.list_owned())
+          self.assertFalse(self.ls.is_owned())
+          self.done.put("not acquired")
+
+      self._addThread(target=_AcquireOne)
+
+      # Wait for timeout in thread to expire
+      self._waitThreads()
+
+      # Release exclusive lock again
+      self.ls.release()
+
+      self.assertEqual(self.done.get_nowait(), "not acquired")
+      self.assertRaises(Queue.Empty, self.done.get_nowait)
+
+  @_Repeat
+  def testDelayedAndExpiringLockAcquire(self):
+    self._setUpLS()
+    self.ls.add(['five', 'six', 'seven', 'eight', 'nine'])
+
+    for expire in (False, True):
+      names = sorted(self.ls._names())
+      self.assertEqual(len(names), 8)
+
+      lock_ev = dict([(i, threading.Event()) for i in names])
+
+      # Lock all in exclusive mode
+      self.assert_(self.ls.acquire(names, shared=0))
+
+      if expire:
+        # We'll wait at least 300ms per lock
+        lockwait = len(names) * [0.3]
+
+        # Fail if we can't acquire all locks in 400ms. There are 8 locks, so
+        # this gives us up to 2.4s to fail.
+        lockall_timeout = 0.4
+      else:
+        # This should finish rather quickly
+        lockwait = None
+        lockall_timeout = len(names) * 5.0
+
+      def _LockAll():
+        def acquire_notification(name):
+          if not expire:
+            self.done.put("getting %s" % name)
+
+          # Kick next lock
+          lock_ev[name].set()
+
+        if self.ls.acquire(names, shared=0, timeout=lockall_timeout,
+                           test_notify=acquire_notification):
+          self.done.put("got all")
+          self.ls.release()
+        else:
+          self.done.put("timeout on all")
+
+        # Notify all locks
+        for ev in lock_ev.values():
+          ev.set()
+
+      t = self._addThread(target=_LockAll)
+
+      for idx, name in enumerate(names):
+        # Wait for actual acquire on this lock to start
+        lock_ev[name].wait(10.0)
+
+        if expire and t.isAlive():
+          # Wait some time after getting the notification to make sure the lock
+          # acquire will expire
+          SafeSleep(lockwait[idx])
+
+        self.ls.release(names=name)
+
+      self.assertFalse(self.ls.list_owned())
+
+      self._waitThreads()
+
+      if expire:
+        # Not checking which locks were actually acquired. Doing so would be
+        # too timing-dependant.
+        self.assertEqual(self.done.get_nowait(), "timeout on all")
+      else:
+        for i in names:
+          self.assertEqual(self.done.get_nowait(), "getting %s" % i)
+        self.assertEqual(self.done.get_nowait(), "got all")
+      self.assertRaises(Queue.Empty, self.done.get_nowait)
+
+  @_Repeat
   def testConcurrentRemove(self):
     self.ls.add('four')
     self.ls.acquire(['one', 'two', 'four'])
@@ -1082,9 +1582,9 @@ class TestLockSet(_ThreadedTestCase):
     self.ls.add('four')
     self.ls.add('five', acquired=1)
     self.ls.add('six', acquired=1, shared=1)
-    self.assertEquals(self.ls._list_owned(),
+    self.assertEquals(self.ls.list_owned(),
       set(['one', 'two', 'three', 'five', 'six']))
-    self.assertEquals(self.ls._is_owned(), True)
+    self.assertEquals(self.ls.is_owned(), True)
     self.assertEquals(self.ls._names(),
       set(['one', 'two', 'three', 'four', 'five', 'six']))
     self.ls.release()
@@ -1123,15 +1623,147 @@ class TestLockSet(_ThreadedTestCase):
     self.assertEqual(self.done.get_nowait(), 'DONE')
     self._setUpLS()
 
+  def testAcquireWithNamesDowngrade(self):
+    self.assertEquals(self.ls.acquire("two", shared=0), set(["two"]))
+    self.assertTrue(self.ls.is_owned())
+    self.assertFalse(self.ls._get_lock().is_owned())
+    self.ls.release()
+    self.assertFalse(self.ls.is_owned())
+    self.assertFalse(self.ls._get_lock().is_owned())
+    # Can't downgrade after releasing
+    self.assertRaises(AssertionError, self.ls.downgrade, "two")
+
+  def testDowngrade(self):
+    # Not owning anything, must raise an exception
+    self.assertFalse(self.ls.is_owned())
+    self.assertRaises(AssertionError, self.ls.downgrade)
+
+    self.assertFalse(compat.any(i.is_owned()
+                                for i in self.ls._get_lockdict().values()))
+    self.assertFalse(self.ls.check_owned(self.ls._names()))
+    for name in self.ls._names():
+      self.assertFalse(self.ls.check_owned(name))
+
+    self.assertEquals(self.ls.acquire(None, shared=0),
+                      set(["one", "two", "three"]))
+    self.assertRaises(AssertionError, self.ls.downgrade, "unknown lock")
+
+    self.assertTrue(self.ls.check_owned(self.ls._names(), shared=0))
+    for name in self.ls._names():
+      self.assertTrue(self.ls.check_owned(name))
+      self.assertTrue(self.ls.check_owned(name, shared=0))
+      self.assertFalse(self.ls.check_owned(name, shared=1))
+
+    self.assertTrue(self.ls._get_lock().is_owned(shared=0))
+    self.assertTrue(compat.all(i.is_owned(shared=0)
+                               for i in self.ls._get_lockdict().values()))
+
+    # Start downgrading locks
+    self.assertTrue(self.ls.downgrade(names=["one"]))
+    self.assertTrue(self.ls._get_lock().is_owned(shared=0))
+    self.assertTrue(compat.all(lock.is_owned(shared=[0, 1][int(name == "one")])
+                               for name, lock in
+                                 self.ls._get_lockdict().items()))
+
+    self.assertFalse(self.ls.check_owned("one", shared=0))
+    self.assertTrue(self.ls.check_owned("one", shared=1))
+    self.assertTrue(self.ls.check_owned("two", shared=0))
+    self.assertTrue(self.ls.check_owned("three", shared=0))
+
+    # Downgrade second lock
+    self.assertTrue(self.ls.downgrade(names="two"))
+    self.assertTrue(self.ls._get_lock().is_owned(shared=0))
+    should_share = lambda name: [0, 1][int(name in ("one", "two"))]
+    self.assertTrue(compat.all(lock.is_owned(shared=should_share(name))
+                               for name, lock in
+                                 self.ls._get_lockdict().items()))
+
+    self.assertFalse(self.ls.check_owned("one", shared=0))
+    self.assertTrue(self.ls.check_owned("one", shared=1))
+    self.assertFalse(self.ls.check_owned("two", shared=0))
+    self.assertTrue(self.ls.check_owned("two", shared=1))
+    self.assertTrue(self.ls.check_owned("three", shared=0))
+
+    # Downgrading the last exclusive lock to shared must downgrade the
+    # lockset-internal lock too
+    self.assertTrue(self.ls.downgrade(names="three"))
+    self.assertTrue(self.ls._get_lock().is_owned(shared=1))
+    self.assertTrue(compat.all(i.is_owned(shared=1)
+                               for i in self.ls._get_lockdict().values()))
+
+    # Verify owned locks
+    for name in self.ls._names():
+      self.assertTrue(self.ls.check_owned(name, shared=1))
+
+    # Downgrading a shared lock must be a no-op
+    self.assertTrue(self.ls.downgrade(names=["one", "three"]))
+    self.assertTrue(self.ls._get_lock().is_owned(shared=1))
+    self.assertTrue(compat.all(i.is_owned(shared=1)
+                               for i in self.ls._get_lockdict().values()))
+
+    self.ls.release()
+
+  def testPriority(self):
+    def _Acquire(prev, next, name, priority, success_fn):
+      prev.wait()
+      self.assert_(self.ls.acquire(name, shared=0,
+                                   priority=priority,
+                                   test_notify=lambda _: next.set()))
+      try:
+        success_fn()
+      finally:
+        self.ls.release()
+
+    # Get all in exclusive mode
+    self.assert_(self.ls.acquire(locking.ALL_SET, shared=0))
+
+    done_two = Queue.Queue(0)
+
+    first = threading.Event()
+    prev = first
+
+    acquires = [("one", prio, self.done) for prio in range(1, 33)]
+    acquires.extend([("two", prio, done_two) for prio in range(1, 33)])
+
+    # Use a deterministic random generator
+    random.Random(741).shuffle(acquires)
+
+    for (name, prio, done) in acquires:
+      ev = threading.Event()
+      self._addThread(target=_Acquire,
+                      args=(prev, ev, name, prio,
+                            compat.partial(done.put, "Prio%s" % prio)))
+      prev = ev
+
+    # Start acquires
+    first.set()
+
+    # Wait for last acquire to start
+    prev.wait()
+
+    # Let threads acquire locks
+    self.ls.release()
+
+    # Wait for threads to finish
+    self._waitThreads()
+
+    for i in range(1, 33):
+      self.assertEqual(self.done.get_nowait(), "Prio%s" % i)
+      self.assertEqual(done_two.get_nowait(), "Prio%s" % i)
+
+    self.assertRaises(Queue.Empty, self.done.get_nowait)
+    self.assertRaises(Queue.Empty, done_two.get_nowait)
+
 
 class TestGanetiLockManager(_ThreadedTestCase):
 
   def setUp(self):
     _ThreadedTestCase.setUp(self)
     self.nodes=['n1', 'n2']
+    self.nodegroups=['g1', 'g2']
     self.instances=['i1', 'i2', 'i3']
-    self.GL = locking.GanetiLockManager(nodes=self.nodes,
-                                        instances=self.instances)
+    self.GL = locking.GanetiLockManager(self.nodes, self.nodegroups,
+                                        self.instances)
 
   def tearDown(self):
     # Don't try this at home...
@@ -1146,62 +1778,80 @@ class TestGanetiLockManager(_ThreadedTestCase):
       self.assertEqual(i, locking.LEVELS[i])
 
   def testDoubleGLFails(self):
-    self.assertRaises(AssertionError, locking.GanetiLockManager)
+    self.assertRaises(AssertionError, locking.GanetiLockManager, [], [], [])
 
   def testLockNames(self):
     self.assertEqual(self.GL._names(locking.LEVEL_CLUSTER), set(['BGL']))
     self.assertEqual(self.GL._names(locking.LEVEL_NODE), set(self.nodes))
+    self.assertEqual(self.GL._names(locking.LEVEL_NODEGROUP),
+                     set(self.nodegroups))
     self.assertEqual(self.GL._names(locking.LEVEL_INSTANCE),
                      set(self.instances))
 
   def testInitAndResources(self):
     locking.GanetiLockManager._instance = None
-    self.GL = locking.GanetiLockManager()
+    self.GL = locking.GanetiLockManager([], [], [])
     self.assertEqual(self.GL._names(locking.LEVEL_CLUSTER), set(['BGL']))
     self.assertEqual(self.GL._names(locking.LEVEL_NODE), set())
+    self.assertEqual(self.GL._names(locking.LEVEL_NODEGROUP), set())
     self.assertEqual(self.GL._names(locking.LEVEL_INSTANCE), set())
 
     locking.GanetiLockManager._instance = None
-    self.GL = locking.GanetiLockManager(nodes=self.nodes)
+    self.GL = locking.GanetiLockManager(self.nodes, self.nodegroups, [])
     self.assertEqual(self.GL._names(locking.LEVEL_CLUSTER), set(['BGL']))
     self.assertEqual(self.GL._names(locking.LEVEL_NODE), set(self.nodes))
+    self.assertEqual(self.GL._names(locking.LEVEL_NODEGROUP),
+                                    set(self.nodegroups))
     self.assertEqual(self.GL._names(locking.LEVEL_INSTANCE), set())
 
     locking.GanetiLockManager._instance = None
-    self.GL = locking.GanetiLockManager(instances=self.instances)
+    self.GL = locking.GanetiLockManager([], [], self.instances)
     self.assertEqual(self.GL._names(locking.LEVEL_CLUSTER), set(['BGL']))
     self.assertEqual(self.GL._names(locking.LEVEL_NODE), set())
+    self.assertEqual(self.GL._names(locking.LEVEL_NODEGROUP), set())
     self.assertEqual(self.GL._names(locking.LEVEL_INSTANCE),
                      set(self.instances))
 
   def testAcquireRelease(self):
     self.GL.acquire(locking.LEVEL_CLUSTER, ['BGL'], shared=1)
-    self.assertEquals(self.GL._list_owned(locking.LEVEL_CLUSTER), set(['BGL']))
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_CLUSTER), set(['BGL']))
     self.GL.acquire(locking.LEVEL_INSTANCE, ['i1'])
+    self.GL.acquire(locking.LEVEL_NODEGROUP, ['g2'])
     self.GL.acquire(locking.LEVEL_NODE, ['n1', 'n2'], shared=1)
+    self.assertTrue(self.GL.check_owned(locking.LEVEL_NODE, ["n1", "n2"],
+                                        shared=1))
+    self.assertFalse(self.GL.check_owned(locking.LEVEL_INSTANCE, ["i1", "i3"]))
     self.GL.release(locking.LEVEL_NODE, ['n2'])
-    self.assertEquals(self.GL._list_owned(locking.LEVEL_NODE), set(['n1']))
-    self.assertEquals(self.GL._list_owned(locking.LEVEL_INSTANCE), set(['i1']))
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_NODE), set(['n1']))
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_NODEGROUP), set(['g2']))
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_INSTANCE), set(['i1']))
     self.GL.release(locking.LEVEL_NODE)
-    self.assertEquals(self.GL._list_owned(locking.LEVEL_NODE), set())
-    self.assertEquals(self.GL._list_owned(locking.LEVEL_INSTANCE), set(['i1']))
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_NODE), set())
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_NODEGROUP), set(['g2']))
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_INSTANCE), set(['i1']))
+    self.GL.release(locking.LEVEL_NODEGROUP)
     self.GL.release(locking.LEVEL_INSTANCE)
     self.assertRaises(errors.LockError, self.GL.acquire,
                       locking.LEVEL_INSTANCE, ['i5'])
     self.GL.acquire(locking.LEVEL_INSTANCE, ['i3'], shared=1)
-    self.assertEquals(self.GL._list_owned(locking.LEVEL_INSTANCE), set(['i3']))
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_INSTANCE), set(['i3']))
 
   def testAcquireWholeSets(self):
     self.GL.acquire(locking.LEVEL_CLUSTER, ['BGL'], shared=1)
     self.assertEquals(self.GL.acquire(locking.LEVEL_INSTANCE, None),
                       set(self.instances))
-    self.assertEquals(self.GL._list_owned(locking.LEVEL_INSTANCE),
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_INSTANCE),
                       set(self.instances))
+    self.assertEquals(self.GL.acquire(locking.LEVEL_NODEGROUP, None),
+                      set(self.nodegroups))
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_NODEGROUP),
+                      set(self.nodegroups))
     self.assertEquals(self.GL.acquire(locking.LEVEL_NODE, None, shared=1),
                       set(self.nodes))
-    self.assertEquals(self.GL._list_owned(locking.LEVEL_NODE),
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_NODE),
                       set(self.nodes))
     self.GL.release(locking.LEVEL_NODE)
+    self.GL.release(locking.LEVEL_NODEGROUP)
     self.GL.release(locking.LEVEL_INSTANCE)
     self.GL.release(locking.LEVEL_CLUSTER)
 
@@ -1209,11 +1859,11 @@ class TestGanetiLockManager(_ThreadedTestCase):
     self.GL.acquire(locking.LEVEL_CLUSTER, ['BGL'], shared=1)
     self.assertEquals(self.GL.acquire(locking.LEVEL_INSTANCE, None),
                       set(self.instances))
-    self.assertEquals(self.GL._list_owned(locking.LEVEL_INSTANCE),
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_INSTANCE),
                       set(self.instances))
     self.assertEquals(self.GL.acquire(locking.LEVEL_NODE, ['n2'], shared=1),
                       set(['n2']))
-    self.assertEquals(self.GL._list_owned(locking.LEVEL_NODE),
+    self.assertEquals(self.GL.list_owned(locking.LEVEL_NODE),
                       set(['n2']))
     self.GL.release(locking.LEVEL_NODE)
     self.GL.release(locking.LEVEL_INSTANCE)
@@ -1224,6 +1874,8 @@ class TestGanetiLockManager(_ThreadedTestCase):
                       locking.LEVEL_NODE, ['n1', 'n2'])
     self.assertRaises(AssertionError, self.GL.acquire,
                       locking.LEVEL_INSTANCE, ['i3'])
+    self.assertRaises(AssertionError, self.GL.acquire,
+                      locking.LEVEL_NODEGROUP, ['g1'])
     self.GL.acquire(locking.LEVEL_CLUSTER, ['BGL'], shared=1)
     self.GL.acquire(locking.LEVEL_NODE, ['n1'])
     self.assertRaises(AssertionError, self.GL.release,
@@ -1237,6 +1889,14 @@ class TestGanetiLockManager(_ThreadedTestCase):
     self.assertRaises(AssertionError, self.GL.release,
                       locking.LEVEL_CLUSTER)
     self.GL.release(locking.LEVEL_INSTANCE)
+    self.GL.acquire(locking.LEVEL_NODEGROUP, None)
+    self.GL.release(locking.LEVEL_NODEGROUP, ['g1'])
+    self.assertRaises(AssertionError, self.GL.release,
+                      locking.LEVEL_CLUSTER, ['BGL'])
+    self.assertRaises(AssertionError, self.GL.release,
+                      locking.LEVEL_CLUSTER)
+    self.GL.release(locking.LEVEL_NODEGROUP)
+    self.GL.release(locking.LEVEL_CLUSTER)
 
   def testWrongOrder(self):
     self.GL.acquire(locking.LEVEL_CLUSTER, ['BGL'], shared=1)
@@ -1244,8 +1904,28 @@ class TestGanetiLockManager(_ThreadedTestCase):
     self.assertRaises(AssertionError, self.GL.acquire,
                       locking.LEVEL_NODE, ['n1'])
     self.assertRaises(AssertionError, self.GL.acquire,
+                      locking.LEVEL_NODEGROUP, ['g1'])
+    self.assertRaises(AssertionError, self.GL.acquire,
                       locking.LEVEL_INSTANCE, ['i2'])
 
+  def testModifiableLevels(self):
+    self.assertRaises(AssertionError, self.GL.add, locking.LEVEL_CLUSTER,
+                      ['BGL2'])
+    self.GL.acquire(locking.LEVEL_CLUSTER, ['BGL'])
+    self.GL.add(locking.LEVEL_INSTANCE, ['i4'])
+    self.GL.remove(locking.LEVEL_INSTANCE, ['i3'])
+    self.GL.remove(locking.LEVEL_INSTANCE, ['i1'])
+    self.assertEqual(self.GL._names(locking.LEVEL_INSTANCE), set(['i2', 'i4']))
+    self.GL.add(locking.LEVEL_NODE, ['n3'])
+    self.GL.remove(locking.LEVEL_NODE, ['n1'])
+    self.assertEqual(self.GL._names(locking.LEVEL_NODE), set(['n2', 'n3']))
+    self.GL.add(locking.LEVEL_NODEGROUP, ['g3'])
+    self.GL.remove(locking.LEVEL_NODEGROUP, ['g2'])
+    self.GL.remove(locking.LEVEL_NODEGROUP, ['g1'])
+    self.assertEqual(self.GL._names(locking.LEVEL_NODEGROUP), set(['g3']))
+    self.assertRaises(AssertionError, self.GL.remove, locking.LEVEL_CLUSTER,
+                      ['BGL2'])
+
   # Helper function to run as a thread that shared the BGL and then acquires
   # some locks at another level.
   def _doLock(self, level, names, shared):
@@ -1290,7 +1970,439 @@ class TestGanetiLockManager(_ThreadedTestCase):
     self.GL.release(locking.LEVEL_CLUSTER, ['BGL'])
 
 
+class TestLockMonitor(_ThreadedTestCase):
+  def setUp(self):
+    _ThreadedTestCase.setUp(self)
+    self.lm = locking.LockMonitor()
+
+  def testSingleThread(self):
+    locks = []
+
+    for i in range(100):
+      name = "TestLock%s" % i
+      locks.append(locking.SharedLock(name, monitor=self.lm))
+
+    self.assertEqual(len(self.lm._locks), len(locks))
+    result = objects.QueryResponse.FromDict(self.lm.QueryLocks(["name"]))
+    self.assertEqual(len(result.fields), 1)
+    self.assertEqual(len(result.data), 100)
+
+    # Delete all locks
+    del locks[:]
+
+    # The garbage collector might needs some time
+    def _CheckLocks():
+      if self.lm._locks:
+        raise utils.RetryAgain()
+
+    utils.Retry(_CheckLocks, 0.1, 30.0)
+
+    self.assertFalse(self.lm._locks)
+
+  def testMultiThread(self):
+    locks = []
+
+    def _CreateLock(prev, next, name):
+      prev.wait()
+      locks.append(locking.SharedLock(name, monitor=self.lm))
+      if next:
+        next.set()
+
+    expnames = []
+
+    first = threading.Event()
+    prev = first
+
+    # Use a deterministic random generator
+    for i in random.Random(4263).sample(range(100), 33):
+      name = "MtTestLock%s" % i
+      expnames.append(name)
+
+      ev = threading.Event()
+      self._addThread(target=_CreateLock, args=(prev, ev, name))
+      prev = ev
+
+    # Add locks
+    first.set()
+    self._waitThreads()
+
+    # Check order in which locks were added
+    self.assertEqual([i.name for i in locks], expnames)
+
+    # Check query result
+    result = self.lm.QueryLocks(["name", "mode", "owner", "pending"])
+    self.assert_(isinstance(result, dict))
+    response = objects.QueryResponse.FromDict(result)
+    self.assertEqual(response.data,
+                     [[(constants.RS_NORMAL, name),
+                       (constants.RS_NORMAL, None),
+                       (constants.RS_NORMAL, None),
+                       (constants.RS_NORMAL, [])]
+                      for name in utils.NiceSort(expnames)])
+    self.assertEqual(len(response.fields), 4)
+    self.assertEqual(["name", "mode", "owner", "pending"],
+                     [fdef.name for fdef in response.fields])
+
+    # Test exclusive acquire
+    for tlock in locks[::4]:
+      tlock.acquire(shared=0)
+      try:
+        def _GetExpResult(name):
+          if tlock.name == name:
+            return [(constants.RS_NORMAL, name),
+                    (constants.RS_NORMAL, "exclusive"),
+                    (constants.RS_NORMAL,
+                     [threading.currentThread().getName()]),
+                    (constants.RS_NORMAL, [])]
+          return [(constants.RS_NORMAL, name),
+                  (constants.RS_NORMAL, None),
+                  (constants.RS_NORMAL, None),
+                  (constants.RS_NORMAL, [])]
+
+        result = self.lm.QueryLocks(["name", "mode", "owner", "pending"])
+        self.assertEqual(objects.QueryResponse.FromDict(result).data,
+                         [_GetExpResult(name)
+                          for name in utils.NiceSort(expnames)])
+      finally:
+        tlock.release()
+
+    # Test shared acquire
+    def _Acquire(lock, shared, ev, notify):
+      lock.acquire(shared=shared)
+      try:
+        notify.set()
+        ev.wait()
+      finally:
+        lock.release()
+
+    for tlock1 in locks[::11]:
+      for tlock2 in locks[::-15]:
+        if tlock2 == tlock1:
+          # Avoid deadlocks
+          continue
+
+        for tlock3 in locks[::10]:
+          if tlock3 in (tlock2, tlock1):
+            # Avoid deadlocks
+            continue
+
+          releaseev = threading.Event()
+
+          # Acquire locks
+          acquireev = []
+          tthreads1 = []
+          for i in range(3):
+            ev = threading.Event()
+            tthreads1.append(self._addThread(target=_Acquire,
+                                             args=(tlock1, 1, releaseev, ev)))
+            acquireev.append(ev)
+
+          ev = threading.Event()
+          tthread2 = self._addThread(target=_Acquire,
+                                     args=(tlock2, 1, releaseev, ev))
+          acquireev.append(ev)
+
+          ev = threading.Event()
+          tthread3 = self._addThread(target=_Acquire,
+                                     args=(tlock3, 0, releaseev, ev))
+          acquireev.append(ev)
+
+          # Wait for all locks to be acquired
+          for i in acquireev:
+            i.wait()
+
+          # Check query result
+          result = self.lm.QueryLocks(["name", "mode", "owner"])
+          response = objects.QueryResponse.FromDict(result)
+          for (name, mode, owner) in response.data:
+            (name_status, name_value) = name
+            (owner_status, owner_value) = owner
+
+            self.assertEqual(name_status, constants.RS_NORMAL)
+            self.assertEqual(owner_status, constants.RS_NORMAL)
+
+            if name_value == tlock1.name:
+              self.assertEqual(mode, (constants.RS_NORMAL, "shared"))
+              self.assertEqual(set(owner_value),
+                               set(i.getName() for i in tthreads1))
+              continue
+
+            if name_value == tlock2.name:
+              self.assertEqual(mode, (constants.RS_NORMAL, "shared"))
+              self.assertEqual(owner_value, [tthread2.getName()])
+              continue
+
+            if name_value == tlock3.name:
+              self.assertEqual(mode, (constants.RS_NORMAL, "exclusive"))
+              self.assertEqual(owner_value, [tthread3.getName()])
+              continue
+
+            self.assert_(name_value in expnames)
+            self.assertEqual(mode, (constants.RS_NORMAL, None))
+            self.assert_(owner_value is None)
+
+          # Release locks again
+          releaseev.set()
+
+          self._waitThreads()
+
+          result = self.lm.QueryLocks(["name", "mode", "owner"])
+          self.assertEqual(objects.QueryResponse.FromDict(result).data,
+                           [[(constants.RS_NORMAL, name),
+                             (constants.RS_NORMAL, None),
+                             (constants.RS_NORMAL, None)]
+                            for name in utils.NiceSort(expnames)])
+
+  def testDelete(self):
+    lock = locking.SharedLock("TestLock", monitor=self.lm)
+
+    self.assertEqual(len(self.lm._locks), 1)
+    result = self.lm.QueryLocks(["name", "mode", "owner"])
+    self.assertEqual(objects.QueryResponse.FromDict(result).data,
+                     [[(constants.RS_NORMAL, lock.name),
+                       (constants.RS_NORMAL, None),
+                       (constants.RS_NORMAL, None)]])
+
+    lock.delete()
+
+    result = self.lm.QueryLocks(["name", "mode", "owner"])
+    self.assertEqual(objects.QueryResponse.FromDict(result).data,
+                     [[(constants.RS_NORMAL, lock.name),
+                       (constants.RS_NORMAL, "deleted"),
+                       (constants.RS_NORMAL, None)]])
+    self.assertEqual(len(self.lm._locks), 1)
+
+  def testPending(self):
+    def _Acquire(lock, shared, prev, next):
+      prev.wait()
+
+      lock.acquire(shared=shared, test_notify=next.set)
+      try:
+        pass
+      finally:
+        lock.release()
+
+    lock = locking.SharedLock("ExcLock", monitor=self.lm)
+
+    for shared in [0, 1]:
+      lock.acquire()
+      try:
+        self.assertEqual(len(self.lm._locks), 1)
+        result = self.lm.QueryLocks(["name", "mode", "owner"])
+        self.assertEqual(objects.QueryResponse.FromDict(result).data,
+                         [[(constants.RS_NORMAL, lock.name),
+                           (constants.RS_NORMAL, "exclusive"),
+                           (constants.RS_NORMAL,
+                            [threading.currentThread().getName()])]])
+
+        threads = []
+
+        first = threading.Event()
+        prev = first
+
+        for i in range(5):
+          ev = threading.Event()
+          threads.append(self._addThread(target=_Acquire,
+                                          args=(lock, shared, prev, ev)))
+          prev = ev
+
+        # Start acquires
+        first.set()
+
+        # Wait for last acquire to start waiting
+        prev.wait()
+
+        # NOTE: This works only because QueryLocks will acquire the
+        # lock-internal lock again and won't be able to get the information
+        # until it has the lock. By then the acquire should be registered in
+        # SharedLock.__pending (otherwise it's a bug).
+
+        # All acquires are waiting now
+        if shared:
+          pending = [("shared", utils.NiceSort(t.getName() for t in threads))]
+        else:
+          pending = [("exclusive", [t.getName()]) for t in threads]
+
+        result = self.lm.QueryLocks(["name", "mode", "owner", "pending"])
+        self.assertEqual(objects.QueryResponse.FromDict(result).data,
+                         [[(constants.RS_NORMAL, lock.name),
+                           (constants.RS_NORMAL, "exclusive"),
+                           (constants.RS_NORMAL,
+                            [threading.currentThread().getName()]),
+                           (constants.RS_NORMAL, pending)]])
+
+        self.assertEqual(len(self.lm._locks), 1)
+      finally:
+        lock.release()
+
+      self._waitThreads()
+
+      # No pending acquires
+      result = self.lm.QueryLocks(["name", "mode", "owner", "pending"])
+      self.assertEqual(objects.QueryResponse.FromDict(result).data,
+                       [[(constants.RS_NORMAL, lock.name),
+                         (constants.RS_NORMAL, None),
+                         (constants.RS_NORMAL, None),
+                         (constants.RS_NORMAL, [])]])
+
+      self.assertEqual(len(self.lm._locks), 1)
+
+  def testDeleteAndRecreate(self):
+    lname = "TestLock101923193"
+
+    # Create some locks with the same name and keep all references
+    locks = [locking.SharedLock(lname, monitor=self.lm)
+             for _ in range(5)]
+
+    self.assertEqual(len(self.lm._locks), len(locks))
+
+    result = self.lm.QueryLocks(["name", "mode", "owner"])
+    self.assertEqual(objects.QueryResponse.FromDict(result).data,
+                     [[(constants.RS_NORMAL, lname),
+                       (constants.RS_NORMAL, None),
+                       (constants.RS_NORMAL, None)]] * 5)
+
+    locks[2].delete()
+
+    # Check information order
+    result = self.lm.QueryLocks(["name", "mode", "owner"])
+    self.assertEqual(objects.QueryResponse.FromDict(result).data,
+                     [[(constants.RS_NORMAL, lname),
+                       (constants.RS_NORMAL, None),
+                       (constants.RS_NORMAL, None)]] * 2 +
+                     [[(constants.RS_NORMAL, lname),
+                       (constants.RS_NORMAL, "deleted"),
+                       (constants.RS_NORMAL, None)]] +
+                     [[(constants.RS_NORMAL, lname),
+                       (constants.RS_NORMAL, None),
+                       (constants.RS_NORMAL, None)]] * 2)
+
+    locks[1].acquire(shared=0)
+
+    last_status = [
+      [(constants.RS_NORMAL, lname),
+       (constants.RS_NORMAL, None),
+       (constants.RS_NORMAL, None)],
+      [(constants.RS_NORMAL, lname),
+       (constants.RS_NORMAL, "exclusive"),
+       (constants.RS_NORMAL, [threading.currentThread().getName()])],
+      [(constants.RS_NORMAL, lname),
+       (constants.RS_NORMAL, "deleted"),
+       (constants.RS_NORMAL, None)],
+      [(constants.RS_NORMAL, lname),
+       (constants.RS_NORMAL, None),
+       (constants.RS_NORMAL, None)],
+      [(constants.RS_NORMAL, lname),
+       (constants.RS_NORMAL, None),
+       (constants.RS_NORMAL, None)],
+      ]
+
+    # Check information order
+    result = self.lm.QueryLocks(["name", "mode", "owner"])
+    self.assertEqual(objects.QueryResponse.FromDict(result).data, last_status)
+
+    self.assertEqual(len(set(self.lm._locks.values())), len(locks))
+    self.assertEqual(len(self.lm._locks), len(locks))
+
+    # Check lock deletion
+    for idx in range(len(locks)):
+      del locks[0]
+      assert gc.isenabled()
+      gc.collect()
+      self.assertEqual(len(self.lm._locks), len(locks))
+      result = self.lm.QueryLocks(["name", "mode", "owner"])
+      self.assertEqual(objects.QueryResponse.FromDict(result).data,
+                       last_status[idx + 1:])
+
+    # All locks should have been deleted
+    assert not locks
+    self.assertFalse(self.lm._locks)
+
+    result = self.lm.QueryLocks(["name", "mode", "owner"])
+    self.assertEqual(objects.QueryResponse.FromDict(result).data, [])
+
+  class _FakeLock:
+    def __init__(self):
+      self._info = []
+
+    def AddResult(self, *args):
+      self._info.append(args)
+
+    def CountPending(self):
+      return len(self._info)
+
+    def GetLockInfo(self, requested):
+      (exp_requested, result) = self._info.pop(0)
+
+      if exp_requested != requested:
+        raise Exception("Requested information (%s) does not match"
+                        " expectations (%s)" % (requested, exp_requested))
+
+      return result
+
+  def testMultipleResults(self):
+    fl1 = self._FakeLock()
+    fl2 = self._FakeLock()
+
+    self.lm.RegisterLock(fl1)
+    self.lm.RegisterLock(fl2)
+
+    # Empty information
+    for i in [fl1, fl2]:
+      i.AddResult(set([query.LQ_MODE, query.LQ_OWNER]), [])
+    result = self.lm.QueryLocks(["name", "mode", "owner"])
+    self.assertEqual(objects.QueryResponse.FromDict(result).data, [])
+    for i in [fl1, fl2]:
+      self.assertEqual(i.CountPending(), 0)
+
+    # Check ordering
+    for fn in [lambda x: x, reversed, sorted]:
+      fl1.AddResult(set(), list(fn([
+        ("aaa", None, None, None),
+        ("bbb", None, None, None),
+        ])))
+      fl2.AddResult(set(), [])
+      result = self.lm.QueryLocks(["name"])
+      self.assertEqual(objects.QueryResponse.FromDict(result).data, [
+        [(constants.RS_NORMAL, "aaa")],
+        [(constants.RS_NORMAL, "bbb")],
+        ])
+      for i in [fl1, fl2]:
+        self.assertEqual(i.CountPending(), 0)
+
+      for fn2 in [lambda x: x, reversed, sorted]:
+        fl1.AddResult(set([query.LQ_MODE]), list(fn([
+          # Same name, but different information
+          ("aaa", "mode0", None, None),
+          ("aaa", "mode1", None, None),
+          ("aaa", "mode2", None, None),
+          ("aaa", "mode3", None, None),
+          ])))
+        fl2.AddResult(set([query.LQ_MODE]), [
+          ("zzz", "end", None, None),
+          ("000", "start", None, None),
+          ] + list(fn2([
+          ("aaa", "b200", None, None),
+          ("aaa", "b300", None, None),
+          ])))
+        result = self.lm.QueryLocks(["name", "mode"])
+        self.assertEqual(objects.QueryResponse.FromDict(result).data, [
+          [(constants.RS_NORMAL, "000"), (constants.RS_NORMAL, "start")],
+          ] + list(fn([
+          # Name is the same, so order must be equal to incoming order
+          [(constants.RS_NORMAL, "aaa"), (constants.RS_NORMAL, "mode0")],
+          [(constants.RS_NORMAL, "aaa"), (constants.RS_NORMAL, "mode1")],
+          [(constants.RS_NORMAL, "aaa"), (constants.RS_NORMAL, "mode2")],
+          [(constants.RS_NORMAL, "aaa"), (constants.RS_NORMAL, "mode3")],
+          ])) + list(fn2([
+          [(constants.RS_NORMAL, "aaa"), (constants.RS_NORMAL, "b200")],
+          [(constants.RS_NORMAL, "aaa"), (constants.RS_NORMAL, "b300")],
+          ])) + [
+          [(constants.RS_NORMAL, "zzz"), (constants.RS_NORMAL, "end")],
+          ])
+        for i in [fl1, fl2]:
+          self.assertEqual(i.CountPending(), 0)
+
+
 if __name__ == '__main__':
-  unittest.main()
-  #suite = unittest.TestLoader().loadTestsFromTestCase(TestSharedLock)
-  #unittest.TextTestRunner(verbosity=2).run(suite)
+  testutils.GanetiTestProgram()