diff --git a/nova/db/sqlalchemy/api.py b/nova/db/sqlalchemy/api.py
index cacee48dbb0d..6bd1db5ca4ff 100644
--- a/nova/db/sqlalchemy/api.py
+++ b/nova/db/sqlalchemy/api.py
@@ -905,21 +905,14 @@ def floating_ip_fixed_ip_associate(context, floating_address,
 @_retry_on_deadlock
 def floating_ip_deallocate(context, address):
     session = get_session()
-
     with session.begin():
-        floating_ip_ref = model_query(context, models.FloatingIp,
-                                      session=session).\
-                          filter_by(address=address).\
-                          filter(models.FloatingIp.project_id != null()).\
-                          with_lockmode('update').\
-                          first()
-
-        if floating_ip_ref:
-            floating_ip_ref.update({'project_id': None,
-                                    'host': None,
-                                    'auto_assigned': False})
-
-    return floating_ip_ref
+        return model_query(context, models.FloatingIp, session=session).\
+            filter_by(address=address).\
+            filter(models.FloatingIp.project_id != null()).\
+            update({'project_id': None,
+                    'host': None,
+                    'auto_assigned': False},
+                   synchronize_session=False)
 
 
 @require_context
diff --git a/nova/network/floating_ips.py b/nova/network/floating_ips.py
index 02beaf122b40..345f51dbb435 100644
--- a/nova/network/floating_ips.py
+++ b/nova/network/floating_ips.py
@@ -278,10 +278,10 @@ class FloatingIP(object):
             LOG.exception(_("Failed to update usages deallocating "
                             "floating IP"))
 
-        floating_ip_ref = objects.FloatingIP.deallocate(context, address)
-        # floating_ip_ref will be None if concurrently another
+        rows_updated = objects.FloatingIP.deallocate(context, address)
+        # number of updated rows will be 0 if concurrently another
         # API call has also deallocated the same floating ip
-        if floating_ip_ref is None:
+        if not rows_updated:
             if reservations:
                 QUOTAS.rollback(context, reservations, project_id=project_id)
         else:
diff --git a/nova/tests/db/test_db_api.py b/nova/tests/db/test_db_api.py
index 9ffa0241e5d5..90c5c002c63a 100644
--- a/nova/tests/db/test_db_api.py
+++ b/nova/tests/db/test_db_api.py
@@ -3894,13 +3894,17 @@ class FloatingIpTestCase(test.TestCase, ModelsObjectComparatorMixin):
     def test_floating_ip_deallocate(self):
         values = {'address': '1.1.1.1', 'project_id': 'fake', 'host': 'fake'}
         float_ip = self._create_floating_ip(values)
-        db.floating_ip_deallocate(self.ctxt, float_ip.address)
+        rows_updated = db.floating_ip_deallocate(self.ctxt, float_ip.address)
+        self.assertEqual(1, rows_updated)
 
         updated_float_ip = db.floating_ip_get(self.ctxt, float_ip.id)
         self.assertIsNone(updated_float_ip.project_id)
         self.assertIsNone(updated_float_ip.host)
         self.assertFalse(updated_float_ip.auto_assigned)
 
+    def test_floating_ip_deallocate_address_not_found(self):
+        self.assertEqual(0, db.floating_ip_deallocate(self.ctxt, '2.2.2.2'))
+
     def test_floating_ip_destroy(self):
         addresses = ['1.1.1.1', '1.1.1.2', '1.1.1.3']
         float_ips = [self._create_floating_ip({'address': addr})