DhcpFilter should always return a valid index if "force_scheduling"

WHen retrieving a vacant DHCP agent binding index, if
"force_scheduling" is set, the method should return a valid binding
index. If the existing binding indexes are sequentially aligned,
the method will return a new one on top; if there is a gap in the
binding indexes list, the first free index will be returned.

Change-Id: Ib4cbeb7c9f0c1e959ad53570320610925ff3d88f
Closes-Bug: #1883513
This commit is contained in:
Rodolfo Alonso Hernandez 2020-06-16 10:28:50 +00:00
parent 7d8f400791
commit ed56429548
2 changed files with 71 additions and 5 deletions

View File

@ -204,13 +204,20 @@ class DhcpFilter(base_resource_filter.BaseResourceFilter):
if open_slots:
return open_slots[0]
if not force_scheduling:
return -1
# Last chance: if this is a manual scheduling, we're gonna allow
# creation of a binding_index even if it will exceed
# max_l3_agents_per_router.
if force_scheduling:
return max(all_indices) + 1
return -1
# dhcp_agents_per_network.
if max(binding_indices) == len(binding_indices):
return max(binding_indices) + 1
else:
# Find binding index set gaps and return first free one.
all_indices = set(range(ndab_model.LOWEST_BINDING_INDEX,
max(binding_indices) + 1))
open_slots = sorted(list(all_indices - set(binding_indices)))
return open_slots[0]
def bind(self, context, agents, network_id, force_scheduling=False):
"""Bind the network to the agents."""

View File

@ -31,6 +31,7 @@ from neutron.objects import agent
from neutron.objects import network as network_obj
from neutron.scheduler import dhcp_agent_scheduler
from neutron.services.segments import db as segments_service_db
from neutron.tests import base
from neutron.tests.common import helpers
from neutron.tests.unit.plugins.ml2 import test_plugin
from neutron.tests.unit import testlib_api
@ -930,3 +931,61 @@ class DHCPAgentAZAwareWeightSchedulerTestCase(TestDhcpSchedulerBaseTestCase):
# which is also not in the same az as the first selected agent.
self.assertEqual('az2-host2', agents_select[1]['host'])
self.assertEqual('az2', agents_select[1]['availability_zone'])
class DhcpFilterTestCase(base.BaseTestCase):
def setUp(self):
super(DhcpFilterTestCase, self).setUp()
self.mock_agent_count = mock.patch.object(agent.Agent, 'count').start()
self.mock_dhcpagent_bindings = mock.patch.object(
network_obj.NetworkDhcpAgentBinding, 'get_objects').start()
cfg.CONF.set_override('dhcp_agents_per_network', 3)
self.dhcp_filter = dhcp_agent_scheduler.DhcpFilter()
def test_get_vacant_network_dhcp_agent_binding_index_no_agents(self):
self.mock_agent_count.return_value = 0
self.mock_dhcpagent_bindings.return_value = []
ret = self.dhcp_filter.get_vacant_network_dhcp_agent_binding_index(
mock.ANY, mock.ANY, False)
self.assertEqual(-1, ret)
def test_get_vacant_network_dhcp_agent_binding_index_several_agents(self):
self.mock_agent_count.return_value = 1
self.mock_dhcpagent_bindings.return_value = []
ret = self.dhcp_filter.get_vacant_network_dhcp_agent_binding_index(
mock.ANY, mock.ANY, False)
self.assertEqual(1, ret)
self.mock_agent_count.return_value = 1
self.mock_dhcpagent_bindings.return_value = [
mock.Mock(binding_index=1)]
ret = self.dhcp_filter.get_vacant_network_dhcp_agent_binding_index(
mock.ANY, mock.ANY, False)
self.assertEqual(-1, ret)
self.mock_agent_count.return_value = 3
self.mock_dhcpagent_bindings.return_value = [
mock.Mock(binding_index=1), mock.Mock(binding_index=3)]
ret = self.dhcp_filter.get_vacant_network_dhcp_agent_binding_index(
mock.ANY, mock.ANY, False)
self.assertEqual(2, ret)
def test_get_vacant_network_dhcp_agent_binding_index_force_sched(self):
self.mock_agent_count.return_value = 3
self.mock_dhcpagent_bindings.return_value = [
mock.Mock(binding_index=1), mock.Mock(binding_index=2),
mock.Mock(binding_index=3), mock.Mock(binding_index=5),
mock.Mock(binding_index=7)]
ret = self.dhcp_filter.get_vacant_network_dhcp_agent_binding_index(
mock.ANY, mock.ANY, True)
self.assertEqual(4, ret)
self.mock_agent_count.return_value = 3
self.mock_dhcpagent_bindings.return_value = [
mock.Mock(binding_index=1), mock.Mock(binding_index=2),
mock.Mock(binding_index=3), mock.Mock(binding_index=4),
mock.Mock(binding_index=5)]
ret = self.dhcp_filter.get_vacant_network_dhcp_agent_binding_index(
mock.ANY, mock.ANY, True)
self.assertEqual(6, ret)