From 59e1796bd2ab04eef52bc1d5a4655edcd925bbf7 Mon Sep 17 00:00:00 2001
From: Rodolfo Alonso Hernandez <ralonsoh@redhat.com>
Date: Thu, 25 Apr 2019 11:02:19 +0000
Subject: [PATCH] Retrieve statistics from TC policy classes

Those statistics will be needed initially to test the TC filter
for VXLAN traffic. Those tests will create several classes on the
same interface with only one filter applied, diverting the traffic
to only one of those classes. Once sample traffic matching the
filter is injected, only the selected class should increase the
packet/byte counters.

Related-Bug: #1560963
Change-Id: Ifc95051b67c031c0dfe209751df3d35c47d61148
---
 neutron/agent/linux/tc_lib.py                 | 22 ++++----
 .../functional/agent/linux/test_tc_lib.py     | 52 +++++++++++++++++++
 2 files changed, 65 insertions(+), 9 deletions(-)

diff --git a/neutron/agent/linux/tc_lib.py b/neutron/agent/linux/tc_lib.py
index 1ccf9fbe12b..952bfbaf89d 100644
--- a/neutron/agent/linux/tc_lib.py
+++ b/neutron/agent/linux/tc_lib.py
@@ -440,15 +440,19 @@ def list_tc_policy_class(device, namespace=None):
         qdisc_type = _get_attr(tc_class, 'TCA_KIND')
         tca_options = _get_attr(tc_class, 'TCA_OPTIONS')
         max_kbps, min_kbps, burst_kb = get_params(tca_options, qdisc_type)
-        classes.append({'device': device,
-                        'index': index,
-                        'namespace': namespace,
-                        'parent': parent,
-                        'classid': classid,
-                        'qdisc_type': qdisc_type,
-                        'min_kbps': min_kbps,
-                        'max_kbps': max_kbps,
-                        'burst_kb': burst_kb})
+        tc_class_data = {'device': device,
+                         'index': index,
+                         'namespace': namespace,
+                         'parent': parent,
+                         'classid': classid,
+                         'qdisc_type': qdisc_type,
+                         'min_kbps': min_kbps,
+                         'max_kbps': max_kbps,
+                         'burst_kb': burst_kb}
+        tca_stats = _get_attr(tc_class, 'TCA_STATS')
+        if tca_stats:
+            tc_class_data['stats'] = tca_stats
+        classes.append(tc_class_data)
 
     return classes
 
diff --git a/neutron/tests/functional/agent/linux/test_tc_lib.py b/neutron/tests/functional/agent/linux/test_tc_lib.py
index 8203f399f44..cc14329982c 100644
--- a/neutron/tests/functional/agent/linux/test_tc_lib.py
+++ b/neutron/tests/functional/agent/linux/test_tc_lib.py
@@ -13,8 +13,13 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+import netaddr
+from oslo_utils import uuidutils
+
 from neutron.agent.linux import ip_lib
 from neutron.agent.linux import tc_lib
+from neutron.privileged.agent.linux import ip_lib as priv_ip_lib
+from neutron.tests.common import net_helpers
 from neutron.tests.functional import base as functional_base
 
 TEST_HZ_VALUE = 250
@@ -83,3 +88,50 @@ class TcLibTestCase(functional_base.BaseSudoTestCase):
         bw_limit, burst = tc.get_tbf_bw_limits()
         self.assertIsNone(bw_limit)
         self.assertIsNone(burst)
+
+
+class TcPolicyClassTestCase(functional_base.BaseSudoTestCase):
+
+    def _remove_ns(self, namespace):
+        priv_ip_lib.remove_netns(namespace)
+
+    def _create_two_namespaces(self):
+        self.ns = ['ns1_' + uuidutils.generate_uuid(),
+                   'ns2_' + uuidutils.generate_uuid()]
+        self.device = ['int1', 'int2']
+        self.mac = []
+        self.ip = ['10.100.0.1/24', '10.100.0.2/24']
+        list(map(priv_ip_lib.create_netns, self.ns))
+        ip_wrapper = ip_lib.IPWrapper(self.ns[0])
+        ip_wrapper.add_veth(self.device[0], self.device[1], self.ns[1])
+        for i in range(2):
+            self.addCleanup(self._remove_ns, self.ns[i])
+            ip_device = ip_lib.IPDevice(self.device[i], self.ns[i])
+            self.mac.append(ip_device.link.address)
+            ip_device.link.set_up()
+            ip_device.addr.add(self.ip[i])
+
+    def test_list_tc_policy_class_retrieve_statistics(self):
+        statistics = {'bytes', 'packets', 'drop', 'overlimits', 'bps', 'pps',
+                      'qlen', 'backlog'}
+        self._create_two_namespaces()
+        tc_lib.add_tc_qdisc(self.device[0], 'htb', parent='root', handle='1:',
+                            namespace=self.ns[0])
+        tc_lib.add_tc_policy_class(self.device[0], '1:', '1:10',
+                                   max_kbps=1000, burst_kb=900, min_kbps=500,
+                                   namespace=self.ns[0])
+        tc_lib.add_tc_filter_match_mac(self.device[0], '1:', '1:10',
+                                       self.mac[1], namespace=self.ns[0])
+        tc_classes = tc_lib.list_tc_policy_class(self.device[0],
+                                                 namespace=self.ns[0])
+        self.assertEqual(1, len(tc_classes))
+        self.assertEqual(statistics, set(tc_classes[0]['stats']))
+
+        bytes = tc_classes[0]['stats']['bytes']
+        packets = tc_classes[0]['stats']['packets']
+        net_helpers.assert_ping(self.ns[1], netaddr.IPNetwork(self.ip[0]).ip,
+                                count=1)
+        tc_classes = tc_lib.list_tc_policy_class(self.device[0],
+                                                 namespace=self.ns[0])
+        self.assertGreater(tc_classes[0]['stats']['bytes'], bytes)
+        self.assertGreater(tc_classes[0]['stats']['packets'], packets)