From 7502c26d385072c0e30a1849a579c44b37bbaf31 Mon Sep 17 00:00:00 2001
From: Kevin Benton <kevin@benton.pub>
Date: Wed, 15 Feb 2017 21:40:07 -0800
Subject: [PATCH] Allow no network to be passed into PortContext

This allows a PortContext to be constructed without a network
passed in for cases like update_port_status that don't examine
bindings, segments, or any other network properties.

In the event that a mechanism driver is loaded that does reference
the 'network' property for these occasions, the context will look
up the network then in a late binding fashion.

This will improve the performance of the update_port_status call
from the provisioning blocks callback, which doesn't provide a
cached network to update_port_status.

Conflicts:
	neutron/plugins/ml2/plugin.py

Partial-Bug: #1665215
Change-Id: I498791614fd456ab67c453cad691f7658d107123
(cherry picked from commit 60edb4c9519543a04d5ccc73c8b5371123fefcd8)
---
 neutron/plugins/ml2/driver_context.py | 7 ++++++-
 neutron/plugins/ml2/plugin.py         | 2 --
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/neutron/plugins/ml2/driver_context.py b/neutron/plugins/ml2/driver_context.py
index afc73911615..43df5d3d808 100644
--- a/neutron/plugins/ml2/driver_context.py
+++ b/neutron/plugins/ml2/driver_context.py
@@ -89,7 +89,7 @@ class PortContext(MechanismDriverContext, api.PortContext):
         self._port = port
         self._original_port = original_port
         self._network_context = NetworkContext(plugin, plugin_context,
-                                               network)
+                                               network) if network else None
         self._binding = binding
         self._binding_levels = binding_levels
         self._segments_to_bind = None
@@ -151,6 +151,11 @@ class PortContext(MechanismDriverContext, api.PortContext):
 
     @property
     def network(self):
+        if not self._network_context:
+            network = self._plugin.get_network(
+                self._plugin_context, self.current['network_id'])
+            self._network_context = NetworkContext(
+                self._plugin, self._plugin_context, network)
         return self._network_context
 
     @property
diff --git a/neutron/plugins/ml2/plugin.py b/neutron/plugins/ml2/plugin.py
index b337af27771..8fefeff7aae 100644
--- a/neutron/plugins/ml2/plugin.py
+++ b/neutron/plugins/ml2/plugin.py
@@ -1732,8 +1732,6 @@ class Ml2Plugin(db_base_plugin_v2.NeutronDbPluginV2,
                 # listening for db events can modify the port if necessary
                 context.session.flush()
                 updated_port = self._make_port_dict(port)
-                network = network or self.get_network(
-                    context, original_port['network_id'])
                 levels = db.get_binding_levels(session, port.id,
                                                port.port_binding.host)
                 mech_context = driver_context.PortContext(