Process port_update notifications in the main agent loop

Instead of processing a port update notification directly in
the RPC call, the actual processing is moved into the main
rpc loop, whereas the RPC call just adds the updated port
identifier to a set of updated ports.
In this way, a port_update notification won't compete with the
main rpc loop, causing long delays into its completion under
heavy load. Also, repeated port_update notifications received
within a single iteration of the main agent loop will be
coalesced and processed only once.
This will also avoid the risk of processing notifications out
of order thus ending up with an actual configuration which
differs from the desired one.

This patch still performs L2 wiring for updated ports even if
it is necessary only when the administrative state of a port
changes.

The update_ports method has been renamed to scan_ports as the latter
name appears to be more in line with what the method actually does.

Partial-Bug: #1253993
Partially implements blueprint: neutron-tempest-parallel
Change-Id: I219c6bdf63b0b5e945b655677f9e28fa591f03cd
This commit is contained in:
Salvatore Orlando 2013-12-12 06:02:13 -08:00 committed by Mark McClain
parent 41badfbdca
commit 5e6e592132
3 changed files with 251 additions and 174 deletions

View File

@ -42,10 +42,8 @@ from neutron.common import legacy
from neutron.common import topics
from neutron.common import utils as q_utils
from neutron import context
from neutron.extensions import securitygroup as ext_sg
from neutron.openstack.common import log as logging
from neutron.openstack.common import loopingcall
from neutron.openstack.common.rpc import common as rpc_common
from neutron.openstack.common.rpc import dispatcher
from neutron.plugins.common import constants as p_const
from neutron.plugins.openvswitch.common import config # noqa
@ -229,6 +227,8 @@ class OVSNeutronAgent(sg_rpc.SecurityGroupAgentRpcCallbackMixin,
self.sg_agent = OVSSecurityGroupAgent(self.context,
self.plugin_rpc,
root_helper)
# Stores port update notifications for processing in main rpc loop
self.updated_ports = set()
# Initialize iteration counter
self.iter_num = 0
@ -293,34 +293,13 @@ class OVSNeutronAgent(sg_rpc.SecurityGroupAgentRpcCallbackMixin,
LOG.debug(_("Network %s not used on agent."), network_id)
def port_update(self, context, **kwargs):
LOG.debug(_("port_update received"))
port = kwargs.get('port')
# Validate that port is on OVS
vif_port = self.int_br.get_vif_port_by_id(port['id'])
if not vif_port:
return
if ext_sg.SECURITYGROUPS in port:
self.sg_agent.refresh_firewall()
network_type = kwargs.get('network_type')
segmentation_id = kwargs.get('segmentation_id')
physical_network = kwargs.get('physical_network')
self.treat_vif_port(vif_port, port['id'], port['network_id'],
network_type, physical_network,
segmentation_id, port['admin_state_up'])
try:
if port['admin_state_up']:
# update plugin about port status
self.plugin_rpc.update_device_up(self.context, port['id'],
self.agent_id,
cfg.CONF.host)
else:
# update plugin about port status
self.plugin_rpc.update_device_down(self.context, port['id'],
self.agent_id,
cfg.CONF.host)
except rpc_common.Timeout:
LOG.error(_("RPC timeout while updating port %s"), port['id'])
# Put the port identifier in the updated_ports set.
# Even if full port details might be provided to this call,
# they are not used since there is no guarantee the notifications
# are processed in the same order as the relevant API requests
self.updated_ports.add(port['id'])
LOG.debug(_("port_update message processed for port %s"), port['id'])
def tunnel_update(self, context, **kwargs):
LOG.debug(_("tunnel_update received"))
@ -830,16 +809,29 @@ class OVSNeutronAgent(sg_rpc.SecurityGroupAgentRpcCallbackMixin,
int_veth.link.set_mtu(self.veth_mtu)
phys_veth.link.set_mtu(self.veth_mtu)
def update_ports(self, registered_ports):
ports = self.int_br.get_vif_port_set()
if ports == registered_ports:
return
self.int_br_device_count = len(ports)
added = ports - registered_ports
removed = registered_ports - ports
return {'current': ports,
'added': added,
'removed': removed}
def scan_ports(self, registered_ports, updated_ports=None):
cur_ports = self.int_br.get_vif_port_set()
self.int_br_device_count = len(cur_ports)
port_info = {'current': cur_ports}
if updated_ports:
# Some updated ports might have been removed in the
# meanwhile, and therefore should not be processed.
# In this case the updated port won't be found among
# current ports.
updated_ports &= cur_ports
if updated_ports:
port_info['updated'] = updated_ports
# FIXME(salv-orlando): It's not really necessary to return early
# if nothing has changed.
if cur_ports == registered_ports:
# No added or removed ports to set, just return here
return port_info
port_info['added'] = cur_ports - registered_ports
# Remove all the known ports not found on the integration bridge
port_info['removed'] = registered_ports - cur_ports
return port_info
def update_ancillary_ports(self, registered_ports):
ports = set()
@ -917,12 +909,13 @@ class OVSNeutronAgent(sg_rpc.SecurityGroupAgentRpcCallbackMixin,
self.tun_br.delete_port(port_name)
self.tun_br_ofports[tunnel_type].pop(remote_ip, None)
def treat_devices_added(self, devices):
def treat_devices_added_or_updated(self, devices):
resync = False
self.sg_agent.prepare_devices_filter(devices)
for device in devices:
LOG.info(_("Port %s added"), device)
LOG.debug(_("Processing port:%s"), device)
try:
# TODO(salv-orlando): Provide bulk API for retrieving
# details for all devices in one call
details = self.plugin_rpc.get_device_details(self.context,
device,
self.agent_id)
@ -942,12 +935,15 @@ class OVSNeutronAgent(sg_rpc.SecurityGroupAgentRpcCallbackMixin,
details['physical_network'],
details['segmentation_id'],
details['admin_state_up'])
# update plugin about port status
self.plugin_rpc.update_device_up(self.context,
device,
self.agent_id,
cfg.CONF.host)
if details.get('admin_state_up'):
LOG.debug(_("Setting status for %s to UP"), device)
self.plugin_rpc.update_device_up(
self.context, device, self.agent_id, cfg.CONF.host)
else:
LOG.debug(_("Setting status for %s to DOWN"), device)
self.plugin_rpc.update_device_down(
self.context, device, self.agent_id, cfg.CONF.host)
else:
LOG.debug(_("Device %s not defined on plugin"), device)
if (port and int(port.ofport) != -1):
@ -1017,11 +1013,30 @@ class OVSNeutronAgent(sg_rpc.SecurityGroupAgentRpcCallbackMixin,
def process_network_ports(self, port_info):
resync_a = False
resync_b = False
if 'added' in port_info:
# If there is an exception while processing security groups ports
# will not be wired anyway, and a resync will be triggered
self.sg_agent.prepare_devices_filter(port_info.get('added', set()))
# TODO(salv-orlando): Optimize by avoiding unnecessary applying
# filters twice to the same ports, and unnecessary calls to the
# plugin (eg: when there are no IP address changes)
if port_info.get('updated'):
self.sg_agent.refresh_firewall()
# VIF wiring needs to be performed always for 'new' devices.
# For updated ports, re-wiring is not needed in most cases, but needs
# to be performed anyway when the admin state of a device is changed.
# TODO(salv-orlando): Optimize for avoiding unnecessary VIF
# processing for updated ports whose admin state is left unchanged
# A device might be both in the 'added' and 'updated'
# list at the same time; avoid processing it twice.
devices_added_updated = (port_info.get('added', set()) |
port_info.get('updated', set()))
if devices_added_updated:
start = time.time()
resync_a = self.treat_devices_added(port_info['added'])
resync_a = self.treat_devices_added_or_updated(
devices_added_updated)
LOG.debug(_("process_network_ports - iteration:%(iter_num)d -"
"treat_devices_added completed in %(elapsed).3f"),
"treat_devices_added_or_updated completed "
"in %(elapsed).3f"),
{'iter_num': self.iter_num,
'elapsed': time.time() - start})
if 'removed' in port_info:
@ -1080,55 +1095,80 @@ class OVSNeutronAgent(sg_rpc.SecurityGroupAgentRpcCallbackMixin,
resync = True
return resync
def _agent_has_updates(self, polling_manager):
return (polling_manager.is_polling_required or
self.updated_ports)
def _port_info_has_changes(self, port_info):
return (port_info.get('added') or
port_info.get('removed') or
port_info.get('updated'))
def rpc_loop(self, polling_manager=None):
if not polling_manager:
polling_manager = polling.AlwaysPoll()
sync = True
ports = set()
updated_ports_copy = set()
ancillary_ports = set()
tunnel_sync = True
while True:
try:
start = time.time()
port_stats = {'regular': {'added': 0, 'removed': 0},
'ancillary': {'added': 0, 'removed': 0}}
LOG.debug(_("Agent rpc_loop - iteration:%d started"),
self.iter_num)
if sync:
LOG.info(_("Agent out of sync with plugin!"))
ports.clear()
ancillary_ports.clear()
sync = False
polling_manager.force_polling()
# Notify the plugin of tunnel IP
if self.enable_tunneling and tunnel_sync:
LOG.info(_("Agent tunnel out of sync with plugin!"))
start = time.time()
port_stats = {'regular': {'added': 0,
'updated': 0,
'removed': 0},
'ancillary': {'added': 0,
'removed': 0}}
LOG.debug(_("Agent rpc_loop - iteration:%d started"),
self.iter_num)
if sync:
LOG.info(_("Agent out of sync with plugin!"))
ports.clear()
ancillary_ports.clear()
sync = False
polling_manager.force_polling()
# Notify the plugin of tunnel IP
if self.enable_tunneling and tunnel_sync:
LOG.info(_("Agent tunnel out of sync with plugin!"))
try:
tunnel_sync = self.tunnel_sync()
if polling_manager.is_polling_required:
except Exception:
LOG.exception(_("Error while synchronizing tunnels"))
tunnel_sync = True
if self._agent_has_updates(polling_manager):
try:
LOG.debug(_("Agent rpc_loop - iteration:%(iter_num)d - "
"starting polling. Elapsed:%(elapsed).3f"),
{'iter_num': self.iter_num,
'elapsed': time.time() - start})
port_info = self.update_ports(ports)
# Save updated ports dict to perform rollback in
# case resync would be needed, and then clear
# self.updated_ports. As the greenthread should not yield
# between these two statements, this will be thread-safe
updated_ports_copy = self.updated_ports
self.updated_ports = set()
port_info = self.scan_ports(ports, updated_ports_copy)
ports = port_info['current']
LOG.debug(_("Agent rpc_loop - iteration:%(iter_num)d - "
"port information retrieved. "
"Elapsed:%(elapsed).3f"),
{'iter_num': self.iter_num,
'elapsed': time.time() - start})
# notify plugin about port deltas
if port_info:
LOG.debug(_("Agent loop has new devices!"))
if self._port_info_has_changes(port_info):
LOG.debug(_("Starting to process devices in:%s"),
port_info)
# If treat devices fails - must resync with plugin
sync = self.process_network_ports(port_info)
LOG.debug(_("Agent rpc_loop - iteration:%(iter_num)d -"
"ports processed. Elapsed:%(elapsed).3f"),
{'iter_num': self.iter_num,
'elapsed': time.time() - start})
ports = port_info['current']
port_stats['regular']['added'] = (
len(port_info.get('added', [])))
port_stats['regular']['updated'] = (
len(port_info.get('updated', [])))
port_stats['regular']['removed'] = (
len(port_info.get('removed', [])))
# Treat ancillary devices if they exist
@ -1157,11 +1197,11 @@ class OVSNeutronAgent(sg_rpc.SecurityGroupAgentRpcCallbackMixin,
sync = sync | rc
polling_manager.polling_completed()
except Exception:
LOG.exception(_("Error in agent event loop"))
sync = True
tunnel_sync = True
except Exception:
LOG.exception(_("Error while processing VIF ports"))
# Put the ports back in self.updated_port
self.updated_ports |= updated_ports_copy
sync = True
# sleep till end of polling interval
elapsed = (time.time() - start)

View File

@ -25,7 +25,6 @@ from neutron.agent.linux import ip_lib
from neutron.agent.linux import ovs_lib
from neutron.agent.linux import utils
from neutron.common import constants as n_const
from neutron.openstack.common.rpc import common as rpc_common
from neutron.plugins.common import constants as p_const
from neutron.plugins.openvswitch.agent import ovs_neutron_agent
from neutron.plugins.openvswitch.common import constants
@ -154,28 +153,69 @@ class TestOvsNeutronAgent(base.BaseTestCase):
self.agent.port_dead(mock.Mock())
self.assertTrue(add_flow_func.called)
def mock_update_ports(self, vif_port_set=None, registered_ports=None):
def mock_scan_ports(self, vif_port_set=None, registered_ports=None,
updated_ports=None):
with mock.patch.object(self.agent.int_br, 'get_vif_port_set',
return_value=vif_port_set):
return self.agent.update_ports(registered_ports)
return self.agent.scan_ports(registered_ports, updated_ports)
def test_update_ports_returns_none_for_unchanged_ports(self):
self.assertIsNone(self.mock_update_ports())
def test_scan_ports_returns_current_only_for_unchanged_ports(self):
vif_port_set = set([1, 3])
registered_ports = set([1, 3])
expected = {'current': vif_port_set}
actual = self.mock_scan_ports(vif_port_set, registered_ports)
self.assertEqual(expected, actual)
def test_update_ports_returns_port_changes(self):
def test_scan_ports_returns_port_changes(self):
vif_port_set = set([1, 3])
registered_ports = set([1, 2])
expected = dict(current=vif_port_set, added=set([3]), removed=set([2]))
actual = self.mock_update_ports(vif_port_set, registered_ports)
actual = self.mock_scan_ports(vif_port_set, registered_ports)
self.assertEqual(expected, actual)
def _test_scan_ports_with_updated_ports(self, updated_ports):
vif_port_set = set([1, 3, 4])
registered_ports = set([1, 2, 4])
expected = dict(current=vif_port_set, added=set([3]),
removed=set([2]), updated=set([4]))
actual = self.mock_scan_ports(vif_port_set, registered_ports,
updated_ports)
self.assertEqual(expected, actual)
def test_scan_ports_finds_known_updated_ports(self):
self._test_scan_ports_with_updated_ports(set([4]))
def test_scan_ports_ignores_unknown_updated_ports(self):
# the port '5' was not seen on current ports. Hence it has either
# never been wired or already removed and should be ignored
self._test_scan_ports_with_updated_ports(set([4, 5]))
def test_scan_ports_ignores_updated_port_if_removed(self):
vif_port_set = set([1, 3])
registered_ports = set([1, 2])
updated_ports = set([1, 2])
expected = dict(current=vif_port_set, added=set([3]),
removed=set([2]), updated=set([1]))
actual = self.mock_scan_ports(vif_port_set, registered_ports,
updated_ports)
self.assertEqual(expected, actual)
def test_scan_ports_no_vif_changes_returns_updated_port_only(self):
vif_port_set = set([1, 2, 3])
registered_ports = set([1, 2, 3])
updated_ports = set([2])
expected = dict(current=vif_port_set, updated=set([2]))
actual = self.mock_scan_ports(vif_port_set, registered_ports,
updated_ports)
self.assertEqual(expected, actual)
def test_treat_devices_added_returns_true_for_missing_device(self):
with mock.patch.object(self.agent.plugin_rpc, 'get_device_details',
side_effect=Exception()):
self.assertTrue(self.agent.treat_devices_added([{}]))
self.assertTrue(self.agent.treat_devices_added_or_updated([{}]))
def _mock_treat_devices_added(self, details, port, func_name):
"""Mock treat devices added.
def _mock_treat_devices_added_updated(self, details, port, func_name):
"""Mock treat devices added or updated.
:param details: the details to return for the device
:param port: the port that get_vif_port_by_id should return
@ -188,29 +228,51 @@ class TestOvsNeutronAgent(base.BaseTestCase):
mock.patch.object(self.agent.int_br, 'get_vif_port_by_id',
return_value=port),
mock.patch.object(self.agent.plugin_rpc, 'update_device_up'),
mock.patch.object(self.agent.plugin_rpc, 'update_device_down'),
mock.patch.object(self.agent, func_name)
) as (get_dev_fn, get_vif_func, upd_dev_up, func):
self.assertFalse(self.agent.treat_devices_added([{}]))
) as (get_dev_fn, get_vif_func, upd_dev_up, upd_dev_down, func):
self.assertFalse(self.agent.treat_devices_added_or_updated([{}]))
return func.called
def test_treat_devices_added_ignores_invalid_ofport(self):
def test_treat_devices_added_updated_ignores_invalid_ofport(self):
port = mock.Mock()
port.ofport = -1
self.assertFalse(self._mock_treat_devices_added(mock.MagicMock(), port,
'port_dead'))
self.assertFalse(self._mock_treat_devices_added_updated(
mock.MagicMock(), port, 'port_dead'))
def test_treat_devices_added_marks_unknown_port_as_dead(self):
def test_treat_devices_added_updated_marks_unknown_port_as_dead(self):
port = mock.Mock()
port.ofport = 1
self.assertTrue(self._mock_treat_devices_added(mock.MagicMock(), port,
'port_dead'))
self.assertTrue(self._mock_treat_devices_added_updated(
mock.MagicMock(), port, 'port_dead'))
def test_treat_devices_added_updates_known_port(self):
def test_treat_devices_added_updated_updates_known_port(self):
details = mock.MagicMock()
details.__contains__.side_effect = lambda x: True
self.assertTrue(self._mock_treat_devices_added(details,
mock.Mock(),
'treat_vif_port'))
self.assertTrue(self._mock_treat_devices_added_updated(
details, mock.Mock(), 'treat_vif_port'))
def test_treat_devices_added_updated_put_port_down(self):
fake_details_dict = {'admin_state_up': False,
'port_id': 'xxx',
'device': 'xxx',
'network_id': 'yyy',
'physical_network': 'foo',
'segmentation_id': 'bar',
'network_type': 'baz'}
with contextlib.nested(
mock.patch.object(self.agent.plugin_rpc, 'get_device_details',
return_value=fake_details_dict),
mock.patch.object(self.agent.int_br, 'get_vif_port_by_id',
return_value=mock.MagicMock()),
mock.patch.object(self.agent.plugin_rpc, 'update_device_up'),
mock.patch.object(self.agent.plugin_rpc, 'update_device_down'),
mock.patch.object(self.agent, 'treat_vif_port')
) as (get_dev_fn, get_vif_func, upd_dev_up,
upd_dev_down, treat_vif_port):
self.assertFalse(self.agent.treat_devices_added_or_updated([{}]))
self.assertTrue(treat_vif_port.called)
self.assertTrue(upd_dev_down.called)
def test_treat_devices_removed_returns_true_for_missing_device(self):
with mock.patch.object(self.agent.plugin_rpc, 'update_device_down',
@ -231,17 +293,36 @@ class TestOvsNeutronAgent(base.BaseTestCase):
def test_treat_devices_removed_ignores_missing_port(self):
self._mock_treat_devices_removed(False)
def _test_process_network_ports(self, port_info):
with contextlib.nested(
mock.patch.object(self.agent.sg_agent, "prepare_devices_filter"),
mock.patch.object(self.agent.sg_agent, "refresh_firewall"),
mock.patch.object(self.agent, "treat_devices_added_or_updated",
return_value=False),
mock.patch.object(self.agent, "treat_devices_removed",
return_value=False)
) as (prep_dev_filter, refresh_fw,
device_added_updated, device_removed):
self.assertFalse(self.agent.process_network_ports(port_info))
prep_dev_filter.assert_called_once_with(port_info['added'])
if port_info.get('updated'):
self.assertEqual(1, refresh_fw.call_count)
device_added_updated.assert_called_once_with(
port_info['added'] | port_info.get('updated', set()))
device_removed.assert_called_once_with(port_info['removed'])
def test_process_network_ports(self):
reply = {'current': set(['tap0']),
'removed': set(['eth0']),
'added': set(['eth1'])}
with mock.patch.object(self.agent, 'treat_devices_added',
return_value=False) as device_added:
with mock.patch.object(self.agent, 'treat_devices_removed',
return_value=False) as device_removed:
self.assertFalse(self.agent.process_network_ports(reply))
self.assertTrue(device_added.called)
self.assertTrue(device_removed.called)
self._test_process_network_ports(
{'current': set(['tap0']),
'removed': set(['eth0']),
'added': set(['eth1'])})
def test_process_network_port_with_updated_ports(self):
self._test_process_network_ports(
{'current': set(['tap0', 'tap1']),
'updated': set(['tap1', 'eth1']),
'removed': set(['eth0']),
'added': set(['eth1'])})
def test_report_state(self):
with mock.patch.object(self.agent.state_rpc,
@ -271,61 +352,15 @@ class TestOvsNeutronAgent(base.BaseTestCase):
recl_fn.assert_called_with("123")
def test_port_update(self):
with contextlib.nested(
mock.patch.object(self.agent.int_br, "get_vif_port_by_id"),
mock.patch.object(self.agent, "treat_vif_port"),
mock.patch.object(self.agent.plugin_rpc, "update_device_up"),
mock.patch.object(self.agent.plugin_rpc, "update_device_down")
) as (getvif_fn, treatvif_fn, updup_fn, upddown_fn):
port = {"id": "123",
"network_id": "124",
"admin_state_up": False}
getvif_fn.return_value = "vif_port_obj"
self.agent.port_update("unused_context",
port=port,
network_type="vlan",
segmentation_id="1",
physical_network="physnet")
treatvif_fn.assert_called_with("vif_port_obj", "123",
"124", "vlan", "physnet",
"1", False)
upddown_fn.assert_called_with(self.agent.context,
"123", self.agent.agent_id,
cfg.CONF.host)
port["admin_state_up"] = True
self.agent.port_update("unused_context",
port=port,
network_type="vlan",
segmentation_id="1",
physical_network="physnet")
updup_fn.assert_called_with(self.agent.context,
"123", self.agent.agent_id,
cfg.CONF.host)
def test_port_update_plugin_rpc_failed(self):
port = {'id': 1,
'network_id': 1,
'admin_state_up': True}
with contextlib.nested(
mock.patch.object(ovs_neutron_agent.LOG, 'error'),
mock.patch.object(self.agent.int_br, "get_vif_port_by_id"),
mock.patch.object(self.agent.plugin_rpc, 'update_device_up'),
mock.patch.object(self.agent, 'port_bound'),
mock.patch.object(self.agent.plugin_rpc, 'update_device_down'),
mock.patch.object(self.agent, 'port_dead')
) as (log, _, device_up, _, device_down, _):
device_up.side_effect = rpc_common.Timeout
self.agent.port_update(mock.Mock(), port=port)
self.assertTrue(device_up.called)
self.assertEqual(log.call_count, 1)
log.reset_mock()
port['admin_state_up'] = False
device_down.side_effect = rpc_common.Timeout
self.agent.port_update(mock.Mock(), port=port)
self.assertTrue(device_down.called)
self.assertEqual(log.call_count, 1)
port = {"id": "123",
"network_id": "124",
"admin_state_up": False}
self.agent.port_update("unused_context",
port=port,
network_type="vlan",
segmentation_id="1",
physical_network="physnet")
self.assertEqual(set(['123']), self.agent.updated_ports)
def test_setup_physical_bridges(self):
with contextlib.nested(

View File

@ -496,23 +496,23 @@ class TunnelTest(base.BaseTestCase):
def test_daemon_loop(self):
reply2 = {'current': set(['tap0']),
'added': set([]),
'added': set(['tap2']),
'removed': set([])}
reply3 = {'current': set(['tap2']),
'added': set([]),
'removed': set([])}
'removed': set(['tap0'])}
with contextlib.nested(
mock.patch.object(log.ContextAdapter, 'exception'),
mock.patch.object(ovs_neutron_agent.OVSNeutronAgent,
'update_ports'),
'scan_ports'),
mock.patch.object(ovs_neutron_agent.OVSNeutronAgent,
'process_network_ports')
) as (log_exception, update_ports, process_network_ports):
) as (log_exception, scan_ports, process_network_ports):
log_exception.side_effect = Exception(
'Fake exception to get out of the loop')
update_ports.side_effect = [reply2, reply3]
scan_ports.side_effect = [reply2, reply3]
process_network_ports.side_effect = [
False, Exception('Fake exception to get out of the loop')]
@ -531,17 +531,19 @@ class TunnelTest(base.BaseTestCase):
except Exception:
pass
log_exception.assert_called_once_with("Error in agent event loop")
update_ports.assert_has_calls([
mock.call(set()),
mock.call(set(['tap0']))
# FIXME(salv-orlando): There should not be assertions on log messages
log_exception.assert_called_once_with(
"Error while processing VIF ports")
scan_ports.assert_has_calls([
mock.call(set(), set()),
mock.call(set(['tap0']), set())
])
process_network_ports.assert_has_calls([
mock.call({'current': set(['tap0']),
'removed': set([]),
'added': set([])}),
'added': set(['tap2'])}),
mock.call({'current': set(['tap2']),
'removed': set([]),
'removed': set(['tap0']),
'added': set([])})
])
self._verify_mock_calls()