Merge "Delete network namespace on last port deletion" into stable/2023.1

Author: Zuul

neutron/agent/linux/dhcp.py

@@ -245,8 +245,9 @@ def clean_devices(self):
 class DhcpLocalProcess(DhcpBase, metaclass=abc.ABCMeta):
     PORTS = []
 
-    # Track running interfaces.
-    _interfaces = set()
+    # Track running interfaces, indexed by network ID, for example,
+    # {net-id-1: set(intf_1, intf_2), net-id-2: set(intf_3, intf_4), ...}
+    _interfaces = collections.defaultdict(set)
 
     def __init__(self, conf, network, process_monitor, version=None,
                  plugin=None, segment=None):
@@ -267,20 +268,24 @@ def __init__(self, conf, network, process_monitor, version=None,
         fileutils.ensure_tree(self.network_conf_dir, mode=0o755)
 
     @classmethod
-    def _add_running_interface(cls, interface):
-        """Safe method that add running interface"""
-        cls._interfaces.add(interface)
+    def _add_running_interface(cls, interface, network_id):
+        """Safe method that adds a given interface"""
+        cls._interfaces[network_id].add(interface)
 
     @classmethod
-    def _del_running_interface(cls, interface):
-        """Safe method that remove given interface"""
-        if interface in cls._interfaces:
-            cls._interfaces.remove(interface)
+    def _del_running_interface(cls, interface, network_id):
+        """Safe method that removes a given interface"""
+        if cls._interfaces.get(network_id):
+            if interface in cls._interfaces[network_id]:
+                cls._interfaces[network_id].remove(interface)
+            # no entries, cleanup
+            if not cls._interfaces[network_id]:
+                del cls._interfaces[network_id]
 
     @classmethod
-    def _has_running_interfaces(cls):
-        """Safe method that remove given interface"""
-        return bool(cls._interfaces)
+    def _has_running_interfaces(cls, network_id):
+        """Safe method that checks for interfaces"""
+        bool(cls._interfaces.get(network_id))
 
     @staticmethod
     def get_confs_dir(conf):
@@ -332,7 +337,8 @@ def _enable(self):
                     self.network, self.segment)
                 self.interface_name = interface_name
                 self.spawn_process()
-                self._add_running_interface(self.interface_name)
+                self._add_running_interface(self.interface_name,
+                                            self.network.id)
             return True
         except exceptions.ProcessExecutionError as error:
             LOG.debug("Spawning DHCP process for network %s failed; "
@@ -364,7 +370,7 @@ def disable(self, retain_port=False, block=False, **kwargs):
                             pm.pid, SIGTERM_TIMEOUT)
                 pm.disable(sig=str(int(signal.SIGKILL)))
                 common_utils.wait_until_true(lambda: not self.active)
-        self._del_running_interface(self.interface_name)
+        self._del_running_interface(self.interface_name, self.network.id)
         if not retain_port:
             self._destroy_namespace_and_port()
             self._remove_config_files()
@@ -376,8 +382,9 @@ def _destroy_namespace_and_port(self):
         except RuntimeError:
             LOG.warning('Failed trying to delete interface: %s',
                         self.interface_name)
-        if not self._has_running_interfaces():
-            # Delete nm only if we don't serve different segmentation id.
+        # Delete namespace only if there are no running interfaces in it,
+        # which covers the case where a network has multiple segmentation ids.
+        if not self._has_running_interfaces(self.network.id):
             try:
                 ip_lib.delete_network_namespace(self.network.namespace)
             except RuntimeError:

neutron/tests/unit/agent/linux/test_dhcp.py

@@ -719,6 +719,17 @@ def __init__(self, domain='openstacklocal'):
                       FakeRouterPort(domain=domain)]
 
 
+class FakeDualNetworkV2(object):
+    def __init__(self, domain='openstacklocal'):
+        self.id = 'dddddddd-dddd-dddd-dddd-dddddddddddd'
+        self.subnets = [FakeV4Subnet(), FakeV6SubnetDHCPStateful()]
+        self.namespace = 'qdhcp-ns-v2'
+        self.ports = [FakePort1(domain=domain), FakeV6Port(domain=domain),
+                      FakeDualPort(domain=domain),
+                      FakeRouterHAPort(),
+                      FakeRouterPort(domain=domain)]
+
+
 class FakeDeviceManagerNetwork(object):
     def __init__(self):
         self.id = 'cccccccc-cccc-cccc-cccc-cccccccccccc'
@@ -1259,6 +1270,37 @@ def test_disable(self):
 
         delete_ns.assert_called_with('qdhcp-ns')
 
+    def test_enable_disable_two_networks(self):
+        attrs_to_mock = {'active': mock.DEFAULT}
+
+        with mock.patch.multiple(LocalChild, **attrs_to_mock) as mocks:
+            mocks['active'].__get__ = mock.Mock(return_value=False)
+            lp = LocalChild(self.conf, FakeDualNetwork())
+            lp2 = LocalChild(self.conf, FakeDualNetworkV2())
+            lp.enable()
+            lp2.enable()
+            with mock.patch('neutron.agent.linux.ip_lib.'
+                            'delete_network_namespace') as delete_ns:
+                lp.disable()
+                self.rmtree.assert_called_once()
+
+            self._assert_disabled(lp)
+
+            delete_ns.assert_called_once()
+            delete_ns.assert_called_with('qdhcp-ns')
+
+            delete_ns.reset_mock()
+            self.rmtree.reset_mock()
+            with mock.patch('neutron.agent.linux.ip_lib.'
+                            'delete_network_namespace') as delete_ns:
+                lp2.disable()
+                self.rmtree.assert_called_once()
+
+            self._assert_disabled(lp2)
+
+            delete_ns.assert_called_once()
+            delete_ns.assert_called_with('qdhcp-ns-v2')
+
     def test_disable_config_dir_removed_after_destroy(self):
         parent = mock.MagicMock()
         parent.attach_mock(self.rmtree, 'rmtree')