Move retry decorator in auto allocate

No longer necessary on cleanup since individual plugin operations
are protected but it should be on _ensure_network_default_value
callback since it can happen outside of a transaction.

Partial-Bug: #1612798
Change-Id: Iab4f2216e6b138296e8245eb0b1e3e6b5e46561b

neutron/services/auto_allocate/db.py

@@ -50,6 +50,7 @@ def _extend_external_network_default(core_plugin, net_res, net_db):
     return net_res
 
 
+@db_api.retry_if_session_inactive()
 def _ensure_external_network_default_value_callback(
     resource, event, trigger, context, request, network):
     """Ensure the is_default db field matches the create/update request."""
@@ -360,8 +361,6 @@ class AutoAllocatedTopologyMixin(common_db_mixin.CommonDbMixin):
                 router_id=router_id, subnets=subnets)
         return network_id
 
-    # FIXME(kevinbenton): get rid of the retry once bug/1612798 is resolved
-    @db_api.retry_db_errors
     def _cleanup(self, context, network_id=None, router_id=None, subnets=None):
         """Clean up auto allocated resources."""
         # Concurrent attempts to delete the topology may interleave and

neutron/tests/unit/services/auto_allocate/test_db.py

@@ -212,15 +212,12 @@ class AutoAllocateTestCase(testlib_api.SqlTestCaseLight):
             self.assertEqual(expected, result)
 
     def test__cleanup_handles_failures(self):
-        retry_then_notfound = (
-            [db_exc.RetryRequest(ValueError())] +
-            [n_exc.NotFound()] * 10
-        )
+        notfound = n_exc.NotFound
         self.mixin._l3_plugin.remove_router_interface.side_effect = (
-            retry_then_notfound)
+            notfound)
         self.mixin._l3_plugin.delete_router.side_effect = (
-            retry_then_notfound)
+            notfound)
         self.mixin._core_plugin.delete_network.side_effect = (
-            retry_then_notfound)
+            notfound)
         self.mixin._cleanup(self.ctx, network_id=44, router_id=45,
                             subnets=[{'id': 46}])