diff --git a/lib/locking.py b/lib/locking.py
index 5a02fd5d4ca33cdba52ff072d345ada7c6f23b56..e28f2f0b1128542629cc73a01f4d121e00ce263e 100644
--- a/lib/locking.py
+++ b/lib/locking.py
@@ -1467,26 +1467,33 @@ class LockSet:
return removed
-# Locking levels, must be acquired in increasing order.
-# Current rules are:
-# - at level LEVEL_CLUSTER resides the Big Ganeti Lock (BGL) which must be
-# acquired before performing any operation, either in shared or in exclusive
-# mode. acquiring the BGL in exclusive mode is discouraged and should be
-# avoided.
-# - at levels LEVEL_NODE and LEVEL_INSTANCE reside node and instance locks.
-# If you need more than one node, or more than one instance, acquire them at
-# the same time.
-LEVEL_CLUSTER = 0
-LEVEL_INSTANCE = 1
-LEVEL_NODEGROUP = 2
-LEVEL_NODE = 3
-#: Level for node resources, used for operations with possibly high impact on
-#: the node's disks.
-LEVEL_NODE_RES = 4
-LEVEL_NETWORK = 5
+# Locking levels, must be acquired in increasing order. Current rules are:
+# - At level LEVEL_CLUSTER resides the Big Ganeti Lock (BGL) which must be
+# acquired before performing any operation, either in shared or exclusive
+# mode. Acquiring the BGL in exclusive mode is discouraged and should be
+# avoided..
+# - At levels LEVEL_NODE and LEVEL_INSTANCE reside node and instance locks. If
+# you need more than one node, or more than one instance, acquire them at the
+# same time.
+# - LEVEL_NODE_RES is for node resources and should be used by operations with
+# possibly high impact on the node's disks.
+# - LEVEL_NODE_ALLOC blocks instance allocations for the whole cluster
+# ("NAL" is the only lock at this level). It should be acquired in shared
+# mode when an opcode blocks all or a significant amount of a cluster's
+# locks. Opcodes doing instance allocations should acquire in exclusive mode.
+# Once the set of acquired locks for an opcode has been reduced to the working
+# set, the NAL should be released as well to allow allocations to proceed.
+(LEVEL_CLUSTER,
+ LEVEL_NODE_ALLOC,
+ LEVEL_INSTANCE,
+ LEVEL_NODEGROUP,
+ LEVEL_NODE,
+ LEVEL_NODE_RES,
+ LEVEL_NETWORK) = range(0, 7)
LEVELS = [
LEVEL_CLUSTER,
+ LEVEL_NODE_ALLOC,
LEVEL_INSTANCE,
LEVEL_NODEGROUP,
LEVEL_NODE,
@@ -1511,11 +1518,15 @@ LEVEL_NAMES = {
LEVEL_NODE: "node",
LEVEL_NODE_RES: "node-res",
LEVEL_NETWORK: "network",
+ LEVEL_NODE_ALLOC: "node-alloc",
}
# Constant for the big ganeti lock
BGL = "BGL"
+#: Node allocation lock
+NAL = "NAL"
+
class GanetiLockManager:
"""The Ganeti Locking Library
@@ -1555,10 +1566,12 @@ class GanetiLockManager:
LEVEL_NODEGROUP: LockSet(nodegroups, "nodegroup", monitor=self._monitor),
LEVEL_INSTANCE: LockSet(instances, "instance", monitor=self._monitor),
LEVEL_NETWORK: LockSet(networks, "network", monitor=self._monitor),
+ LEVEL_NODE_ALLOC: LockSet([NAL], "node-alloc", monitor=self._monitor),
}
assert compat.all(ls.name == LEVEL_NAMES[level]
- for (level, ls) in self.__keyring.items())
+ for (level, ls) in self.__keyring.items()), \
+ "Keyring name mismatch"
def AddToLockMonitor(self, provider):
"""Registers a new lock with the monitor.
diff --git a/test/ganeti.locking_unittest.py b/test/ganeti.locking_unittest.py
index 45c8f6d460dca74d5b112e8f78f12c17ccba2858..04b46fce05eb9545550256359752d47abc312c2b 100755
--- a/test/ganeti.locking_unittest.py
+++ b/test/ganeti.locking_unittest.py
@@ -1804,6 +1804,7 @@ class TestGanetiLockManager(_ThreadedTestCase):
def testLockNames(self):
self.assertEqual(self.GL._names(locking.LEVEL_CLUSTER), set(["BGL"]))
+ self.assertEqual(self.GL._names(locking.LEVEL_NODE_ALLOC), set(["NAL"]))
self.assertEqual(self.GL._names(locking.LEVEL_NODE), set(self.nodes))
self.assertEqual(self.GL._names(locking.LEVEL_NODEGROUP),
set(self.nodegroups))
@@ -1816,6 +1817,7 @@ class TestGanetiLockManager(_ThreadedTestCase):
locking.GanetiLockManager._instance = None
self.GL = locking.GanetiLockManager([], [], [], [])
self.assertEqual(self.GL._names(locking.LEVEL_CLUSTER), set(["BGL"]))
+ self.assertEqual(self.GL._names(locking.LEVEL_NODE_ALLOC), set(["NAL"]))
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())
@@ -1824,6 +1826,7 @@ class TestGanetiLockManager(_ThreadedTestCase):
locking.GanetiLockManager._instance = None
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_ALLOC), set(["NAL"]))
self.assertEqual(self.GL._names(locking.LEVEL_NODE), set(self.nodes))
self.assertEqual(self.GL._names(locking.LEVEL_NODEGROUP),
set(self.nodegroups))
@@ -1833,6 +1836,7 @@ class TestGanetiLockManager(_ThreadedTestCase):
locking.GanetiLockManager._instance = None
self.GL = locking.GanetiLockManager([], [], self.instances, [])
self.assertEqual(self.GL._names(locking.LEVEL_CLUSTER), set(["BGL"]))
+ self.assertEqual(self.GL._names(locking.LEVEL_NODE_ALLOC), set(["NAL"]))
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),
@@ -1841,6 +1845,7 @@ class TestGanetiLockManager(_ThreadedTestCase):
locking.GanetiLockManager._instance = None
self.GL = locking.GanetiLockManager([], [], [], self.networks)
self.assertEqual(self.GL._names(locking.LEVEL_CLUSTER), set(["BGL"]))
+ self.assertEqual(self.GL._names(locking.LEVEL_NODE_ALLOC), set(["NAL"]))
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())
@@ -1946,6 +1951,8 @@ class TestGanetiLockManager(_ThreadedTestCase):
def testModifiableLevels(self):
self.assertRaises(AssertionError, self.GL.add, locking.LEVEL_CLUSTER,
["BGL2"])
+ self.assertRaises(AssertionError, self.GL.add, locking.LEVEL_NODE_ALLOC,
+ ["NAL2"])
self.GL.acquire(locking.LEVEL_CLUSTER, ["BGL"])
self.GL.add(locking.LEVEL_INSTANCE, ["i4"])
self.GL.remove(locking.LEVEL_INSTANCE, ["i3"])