[Functional] Fix expected number of the enqueue_state_change calls

In the HA router's keepalived state change monitor tests, it was
expected that enqueue_state_change method will be called 3 or 4 times.
But after some changes in the keepalived_state_change monitor which were
done some time ago, it may be now that it will be called just 2 or 3
times:
- 2 when initial status will be "primary" and it will be just
  transition to "backup",
- 3 when initial status will be "backup", then it will transition to
  "primary" and finally to "backup" again.

To reflect those 2 possibilities, test was changed that it will expect
2 or 3 calls and will check only that last 2 will be always transition
to "primary" and then to "backup".

Additionally this patch adds some extra logging in that test so it will
be easier to check what was going on in that test.

Conflicts:
    neutron/tests/functional/agent/l3/test_ha_router.py

Closes-Bug: #1954751
Change-Id: Ib5de7e65839f52c35c43801969e3f0c16dead5bb
(cherry picked from commit c6a6c5ae12)
(cherry picked from commit 533ca2c99c)

neutron/tests/functional/agent/l3/framework.py

@@ -45,6 +45,8 @@ from neutron.tests.common import net_helpers
 from neutron.tests.functional import base
 
 
+LOG = logging.getLogger(__name__)
+
 _uuid = uuidutils.generate_uuid
 
 OVS_INTERFACE_DRIVER = 'neutron.agent.linux.interface.OVSInterfaceDriver'
@@ -169,6 +171,7 @@ class L3AgentTestFramework(base.BaseSudoTestCase):
                                                   qos_policy_id=qos_policy_id)
 
     def change_router_state(self, router_id, state):
+        LOG.debug("Router %s state changed to '%s'", router_id, state)
         ri = self.agent.router_info.get(router_id)
         if not ri:
             self.fail('Router %s is not present in the L3 agent' % router_id)

neutron/tests/functional/agent/l3/test_ha_router.py

@@ -17,6 +17,7 @@ import copy
 
 import mock
 from neutron_lib import constants
+from oslo_log import log as logging
 from oslo_utils import netutils
 import testtools
 
@@ -29,6 +30,9 @@ from neutron.tests.common import net_helpers
 from neutron.tests.functional.agent.l3 import framework
 
 
+LOG = logging.getLogger(__name__)
+
+
 class L3HATestCase(framework.L3AgentTestFramework):
 
     def test_ha_router_update_floatingip_statuses(self):
@@ -46,11 +50,13 @@ class L3HATestCase(framework.L3AgentTestFramework):
         self.fail_ha_router(router)
         common_utils.wait_until_true(lambda: router.ha_state == 'backup')
 
-        common_utils.wait_until_true(lambda:
-            (enqueue_mock.call_count == 3 or enqueue_mock.call_count == 4))
+        def enqueue_call_count_match():
+            LOG.debug("enqueue_mock called %s times.", enqueue_mock.call_count)
+            return enqueue_mock.call_count in [2, 3]
+
+        common_utils.wait_until_true(enqueue_call_count_match)
         calls = [args[0] for args in enqueue_mock.call_args_list]
-        self.assertEqual((router.router_id, 'backup'), calls[0])
-        self.assertEqual((router.router_id, 'master'), calls[1])
+        self.assertEqual((router.router_id, 'master'), calls[-2])
         self.assertEqual((router.router_id, 'backup'), calls[-1])
 
     def _expected_rpc_report(self, expected):