smoketest: ethernet: rfs: T4689: also test default "0" case

In addition to verify the queue lengths when CLI option is set, we also need
to verify that all values are resetted back to "0" which is the Kernel default.

smoketest/scripts/cli/test_interfaces_ethernet.py

@@ -192,17 +192,36 @@ def test_offloading_rfs(self):
 
         for interface in self._interfaces:
             self.cli_set(self._base_path + [interface, 'offload', 'rfs'])
+
         self.cli_commit()
 
         for interface in self._interfaces:
-            queues = glob(f'/sys/class/net/{interface}/queues/rx-*')
-            rfs_flow = global_rfs_flow/len(queues)
-            for i in range(0,len(queues)):
-                flows = read_file(f'/sys/class/net/{interface}/queues/rx-{i}/rps_flow_cnt')
-                self.assertEqual(int(flows), int(rfs_flow))
-
-        global_flows = read_file(f'/proc/sys/net/core/rps_sock_flow_entries')
-        self.assertEqual(int(global_flows), int(global_rfs_flow))
+            queues = len(glob(f'/sys/class/net/{interface}/queues/rx-*'))
+            rfs_flow = int(global_rfs_flow/queues)
+            for i in range(0, queues):
+                tmp = read_file(f'/sys/class/net/{interface}/queues/rx-{i}/rps_flow_cnt')
+                self.assertEqual(int(tmp), rfs_flow)
+
+        tmp = read_file(f'/proc/sys/net/core/rps_sock_flow_entries')
+        self.assertEqual(int(tmp), global_rfs_flow)
+
+
+        # delete configuration of RFS and check all values returned to default "0"
+        for interface in self._interfaces:
+            self.cli_delete(self._base_path + [interface, 'offload', 'rfs'])
+
+        self.cli_commit()
+
+        for interface in self._interfaces:
+            queues = len(glob(f'/sys/class/net/{interface}/queues/rx-*'))
+            rfs_flow = int(global_rfs_flow/queues)
+            for i in range(0, queues):
+                tmp = read_file(f'/sys/class/net/{interface}/queues/rx-{i}/rps_flow_cnt')
+                self.assertEqual(int(tmp), 0)
+
+        tmp = read_file(f'/proc/sys/net/core/rps_sock_flow_entries')
+        self.assertEqual(int(tmp), 0)
+
 
     def test_non_existing_interface(self):
         unknonw_interface = self._base_path + ['eth667']