Instance delete always stops partition

Instance delete always stops partition even if partition ia already stoped.
Work around is when it try to stop the partition which
is already stopped, then catch exception and pass it.

Closes-Bug: #1701506

Change-Id: I8ddb84de307bc58fa68136c503408a2d65ef629a
Signed-off-by: Prabhat Ranjan <pranjank@in.ibm.com>

nova_dpm/tests/unit/virt/dpm/test_vm.py

@@ -20,6 +20,8 @@ from nova.objects import instance as instance_obj
 from nova.test import TestCase
 from nova_dpm.virt.dpm import exceptions
 from nova_dpm.virt.dpm import vm
+
+import mock
 import zhmcclient
 import zhmcclient_mock
 
@@ -43,6 +45,14 @@ def fake_session():
         'maximum-memory': 512,
         'ifl-processors': 3
     })
+    cpc1.partitions.add({
+        'name': 'OpenStack-foo-6511ee0f-0d64-4392-aaaa-bbbbbbbbbbbb',
+        'description': 'OpenStack CPCSubset=foo',
+        'initial-memory': 512,
+        'status': 'stopped',
+        'maximum-memory': 512,
+        'ifl-processors': 3
+    })
     adapter1 = cpc1.adapters.add({
         'object-id': '6511ee0f-0d64-4392-b9e0-cdbea10a17c3',
         'name': 'fcp_1',
@@ -271,6 +281,13 @@ class VmPartitionInstanceTestCase(TestCase):
                 'object-uri') + '/hbas/1',
             self.partition_inst.get_boot_hba_uri())
 
+    def test_destroy_stopped_partition(self):
+        instance = instance_obj.Instance()
+        instance.save = mock.Mock()
+        instance.uuid = '6511ee0f-0d64-4392-aaaa-bbbbbbbbbbbb'
+        partition_inst = vm.PartitionInstance(instance, self.cpc)
+        partition_inst.destroy()
+
 
 class PhysicalAdapterModelTestCase(TestCase):
 

nova_dpm/virt/dpm/vm.py

@@ -32,6 +32,7 @@ from nova_dpm.virt.dpm import exceptions
 from nova_dpm.virt.dpm import utils
 from oslo_log import log as logging
 from zhmcclient._exceptions import NotFound
+from zhmcclient import HTTPError
 
 CONF = conf.CONF
 OPENSTACK_PREFIX = 'OpenStack'
@@ -289,7 +290,18 @@ class PartitionInstance(object):
     def destroy(self):
         LOG.debug('Partition Destroy triggered')
         if self.partition:
-            self.partition.stop(True)
+            try:
+                self.partition.stop(True)
+            except HTTPError as http_error:
+                # (http_status == 409 and reason == 1) means
+                # Partition status is not valid to perform the operation.
+                # e.g - If partition is already stop then stop operation
+                # is not a valid operation on partition.
+                if http_error.http_status == 409 and http_error.reason == 1:
+                    pass
+                else:
+                    raise http_error
+
             # TODO(preethipy): The below method to be removed once the bug
             # on DPM is fixed to return correct status on API return
             self._loop_status_update(5, 'stopped')