HPE 3PAR: Fix to use small QoS Latency value

If QoS Latency is created with small value (less than 1; eg 0.1),
then during create volume, below error occurs:

Exception: invalid literal for int() with base 10: '0.1'

This patch is submitted to handle small QoS Latency values.

Closes-Bug: #2018994
Change-Id: I09cc3986a7be614f8870f3712eb05b5adfed2425

cinder/tests/unit/volume/drivers/hpe/test_hpe3par.py

@@ -1107,19 +1107,26 @@ class TestHPE3PARDriverBase(HPE3PARBaseDriver):
 
             self.assertEqual(expected_cpg, result['snap_cpg'])
 
+    # (i) normal value; eg. 7, 10, etc
+    # (ii) small value less than 1; eg. 0.1, 0.02, etc
+    @ddt.data({'latency': 25}, {'latency': 0.2})
+    @ddt.unpack
     @mock.patch.object(volume_types, 'get_volume_type')
-    def test_create_volume_qos(self, _mock_volume_types):
+    def test_create_volume_qos(self, _mock_volume_types, latency):
         # setup_mock_client drive with default configuration
         # and return the mock HTTP 3PAR client
         mock_client = self.setup_driver()
 
+        QOS = self.QOS.copy()
+        QOS['qos:latency'] = latency
+
         _mock_volume_types.return_value = {
             'name': 'gold',
             'extra_specs': {
                 'cpg': HPE3PAR_CPG_QOS,
                 'snap_cpg': HPE3PAR_CPG_SNAP,
                 'vvs_name': self.VVS_NAME,
-                'qos': self.QOS,
+                'qos': QOS,
                 'tpvv': True,
                 'tdvv': False,
                 'volume_type': self.volume_type}}

cinder/volume/drivers/hpe/hpe_3par_common.py

@@ -304,11 +304,12 @@ class HPE3PARCommon(object):
         4.0.18 - During conversion of volume to base volume,
                  error out if it has child snapshot(s). Bug #1994521
         4.0.19 - Update code to work with new WSAPI (of 2023). Bug #2015746
+        4.0.20 - Use small QoS Latency value. Bug #2018994
 
 
     """
 
-    VERSION = "4.0.19"
+    VERSION = "4.0.20"
 
     stats = {}
 
@@ -2051,7 +2052,17 @@ class HPE3PARCommon(object):
             if min_bw is None:
                 qosRule['bwMinGoalKB'] = int(max_bw) * units.Ki
         if latency:
-            qosRule['latencyGoal'] = int(latency)
+            # latency could be values like 2, 5, etc or
+            # small values like 0.1, 0.02, etc.
+            # we are converting to float so that 0.1 doesn't become 0
+            latency = float(latency)
+            if latency >= 1:
+                # by default, latency in millisecs
+                qosRule['latencyGoal'] = int(latency)
+            else:
+                # latency < 1 Eg. 0.1, 0.02, etc
+                # convert latency to microsecs
+                qosRule['latencyGoaluSecs'] = int(latency * 1000)
         if priority:
             qosRule['priority'] = self.qos_priority_level.get(priority.lower())
 

releasenotes/notes/hpe-3par-small-qos-latency-values-d5fa70a605b04335.yaml

@@ -0,0 +1,6 @@
+---
+fixes:
+  - |
+    HPE 3PAR driver `bug #2018994
+    <https://bugs.launchpad.net/cinder/+bug/2018994>`_:
+    Fixed: use small QoS Latency value (less than 1)