[SVF]:Fix multiple lsiogrp,lsvdisk calls in Retype.

[Spectrum Virtualize Family] During Retype operation
there are multiple lsiogrp and lsvdisk calls
which can be optimized .

This patch fixes can optimize ssh calls by caching the
io_grp information and passing it as an argument to
_verify_retype_params function which can remove
get_volume_io_group function call inside
_verify_retype_params .

Closes Bug: #1951250

Change-Id: I98562783225523b6f7193edf499563b1b11daace

cinder/tests/unit/volume/drivers/ibm/test_storwize_svc.py

@@ -11160,7 +11160,10 @@ class StorwizeSVCReplicationTestCase(test.TestCase):
         self.driver.retype(self.ctxt, volume,
                            new_type, diff, host)
 
-    def test_storwize_svc_retype_global_mirror_volume_to_thin(self):
+    @mock.patch.object(storwize_svc_common.StorwizeHelpers,
+                       'get_volume_io_group')
+    def test_storwize_svc_retype_global_mirror_volume_to_thin(self,
+                                                              get_vol_io_grp):
         self.driver.do_setup(self.ctxt)
         loc = ('StorwizeSVCDriver:' + self.driver._state['system_id'] +
                ':openstack')
@@ -11170,6 +11173,8 @@ class StorwizeSVCReplicationTestCase(test.TestCase):
                 'capabilities': cap}
         ctxt = context.get_admin_context()
 
+        get_vol_io_grp.return_value = 0
+
         type_name = 'rep_global_none'
         spec = {'replication_enabled': '<is> True',
                 'replication_type': '<in> global',
@@ -11201,6 +11206,7 @@ class StorwizeSVCReplicationTestCase(test.TestCase):
         self.driver.retype(self.ctxt, vol1, vol_type2, diff, host)
         copies = self.driver._helpers.lsvdiskcopy(vol1.name)
         self.assertEqual(2, len(copies))
+        get_vol_io_grp.assert_called_once_with(vol1.name)
         self.driver.delete_volume(vol1)
 
     def test_storwize_svc_retype_global_mirror_volume_to_none(self):

cinder/volume/drivers/ibm/storwize_svc/storwize_svc_common.py

@@ -5142,7 +5142,7 @@ class StorwizeSVCCommonDriver(san.SanDriver,
 
     def _verify_retype_params(self, volume, new_opts, old_opts, need_copy,
                               change_mirror, new_rep_type, old_rep_type,
-                              vdisk_changes, old_pool, new_pool):
+                              vdisk_changes, old_pool, new_pool, old_io_grp):
         # Some volume parameters can not be changed or changed at the same
         # time during volume retype operation. This function checks the
         # retype parameters.
@@ -5195,7 +5195,6 @@ class StorwizeSVCCommonDriver(san.SanDriver,
                 need_check_dr_pool_param = True
 
         if new_rep_type != old_rep_type:
-            old_io_grp = self._helpers.get_volume_io_group(volume.name)
             if (old_io_grp not in
                     StorwizeHelpers._get_valid_requested_io_groups(
                         self._state, new_opts)):
@@ -5401,10 +5400,10 @@ class StorwizeSVCCommonDriver(san.SanDriver,
         old_io_grp = self._helpers.get_volume_io_group(volume['name'])
         new_io_grp = self._helpers.select_io_group(self._state,
                                                    new_opts, new_pool)
-
         self._verify_retype_params(volume, new_opts, old_opts, need_copy,
                                    change_mirror, new_rep_type, old_rep_type,
-                                   vdisk_changes, old_pool, new_pool)
+                                   vdisk_changes, old_pool, new_pool,
+                                   old_io_grp)
 
         if old_opts['volume_topology'] or new_opts['volume_topology']:
             self._check_hyperswap_retype_params(volume, new_opts, old_opts,

releasenotes/notes/bug-1951250-storwize-fix-multiple-ssh-calls-for-retype-d3b56379b7d8b049.yaml

@@ -0,0 +1,7 @@
+---
+fixes:
+  - |
+    IBM Spectrum Virtualize Family driver
+    `Bug #1920870 <https://bugs.launchpad.net/cinder/+bug/1951250>`_:
+    Reduce multiple lsiogrp, lsvdisk calls in Retype operaton
+    to optimize the code.