openstack/os-vif
Code Issues Proposed changes

Check for concurrent bridge creation in bridge add

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With Linux bridge, either Neutron or Nova may create the bridge
associated with a network so this process must be robust to
concurrent creations of the same bridge.

This change just has the addbr call capture exceptions and avoid
reraising if the device already exists.

Closes-Bug: #1617447
Change-Id: Ib0266086e0caffecf3f9f2a8291369cfa155f386
This commit is contained in:
Kevin Benton 2016-08-26 15:56:24 -07:00
parent b088d21b91
commit c25ce5a852
2 changed files with 26 additions and 1 deletions
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7
vif_plug_linux_bridge/linux_net.py
View File

@ -24,6 +24,7 @@ import os
from oslo_concurrency import lockutils
from oslo_concurrency import processutils
from oslo_log import log as logging
from oslo_utils import excutils
from vif_plug_linux_bridge import privsep
@ -122,7 +123,11 @@ def _ensure_bridge_privileged(bridge, interface, net_attrs, gateway,
"""
if not device_exists(bridge):
LOG.debug('Starting Bridge %s', bridge)
processutils.execute('brctl', 'addbr', bridge)
try:
processutils.execute('brctl', 'addbr', bridge)
except Exception:
with excutils.save_and_reraise_exception() as ectx:
ectx.reraise = not device_exists(bridge)
processutils.execute('brctl', 'setfd', bridge, 0)
# processutils.execute('brctl setageing %s 10' % bridge)
processutils.execute('brctl', 'stp', bridge, 'off')

20
vif_plug_linux_bridge/tests/test_linux_net.py
View File

@ -94,6 +94,26 @@ class LinuxNetTest(testtools.TestCase):
self.assertEqual([], mock_exec.mock_calls)
mock_dev_exists.assert_called_once_with("br0")
@mock.patch.object(processutils, "execute")
@mock.patch.object(linux_net, "device_exists", return_value=False)
def test_ensure_bridge_addbr_exception(self, mock_dev_exists, mock_exec):
mock_exec.side_effect = ValueError()
with testtools.ExpectedException(ValueError):
linux_net.ensure_bridge("br0", None, filtering=False)
@mock.patch.object(processutils, "execute")
@mock.patch.object(linux_net, "device_exists", side_effect=[False, True])
def test_ensure_bridge_concurrent_add(self, mock_dev_exists, mock_exec):
mock_exec.side_effect = [ValueError(), 0, 0, 0]
linux_net.ensure_bridge("br0", None, filtering=False)
calls = [mock.call('brctl', 'addbr', 'br0'),
mock.call('brctl', 'setfd', 'br0', 0),
mock.call('brctl', 'stp', 'br0', "off"),
mock.call('ip', 'link', 'set', 'br0', "up")]
self.assertEqual(calls, mock_exec.mock_calls)
mock_dev_exists.assert_has_calls([mock.call("br0"), mock.call("br0")])
@mock.patch.object(os.path, "exists", return_value=False)
@mock.patch.object(processutils, "execute")
@mock.patch.object(linux_net, "device_exists", return_value=False)