From a2d77845ab247f1b09e2ae4f32f9421c3f50b98d Mon Sep 17 00:00:00 2001
From: sdmitriev1 <sdmitriev1@gmail.com>
Date: Sun, 12 Dec 2021 16:45:59 +0000
Subject: [PATCH] Functional test
 test_boot_reschedule_with_proper_pci_device_count

Lets first ensure we have a test that proves we have bad behaviour,
then follow up with the fix and the test tweak to prove it.

On the first compute node it fails due to group policy error.
On the second compute node instance should have exactly one PCI device.

Related-Bug: #1860555
Change-Id: Ia122fff268c8f45ad3e5a3071d2cb7c990cb2c1d
---
 .../libvirt/test_pci_sriov_servers.py         | 59 +++++++++++++++++++
 1 file changed, 59 insertions(+)

diff --git a/nova/tests/functional/libvirt/test_pci_sriov_servers.py b/nova/tests/functional/libvirt/test_pci_sriov_servers.py
index d1a32771eb..d7ceaaf04c 100644
--- a/nova/tests/functional/libvirt/test_pci_sriov_servers.py
+++ b/nova/tests/functional/libvirt/test_pci_sriov_servers.py
@@ -3006,6 +3006,65 @@ class PCIServersTest(_PCIServersTestBase):
         self.assert_no_pci_healing("test_compute0")
 
 
+class PCIResourceRequestReschedulingTest(_PCIServersTestBase):
+
+    # Needed for networks=none
+    microversion = '2.37'
+
+    PFS_ALIAS_NAME = 'pfs'
+    PCI_DEVICE_SPEC = [jsonutils.dumps(x) for x in (
+        {
+            'vendor_id': fakelibvirt.PCI_VEND_ID,
+            'product_id': fakelibvirt.PF_PROD_ID,
+        },
+    )]
+    PCI_ALIAS = [jsonutils.dumps(x) for x in (
+        {
+            'vendor_id': fakelibvirt.PCI_VEND_ID,
+            'product_id': fakelibvirt.PF_PROD_ID,
+            'device_type': fields.PciDeviceType.SRIOV_PF,
+            'name': PFS_ALIAS_NAME,
+        },
+    )]
+
+    def test_boot_reschedule_with_proper_pci_device_count(self):
+        """Verify that in case of rescheduling instance with PCI device request
+        instance has proper count of pci devices.
+        """
+        pci_info = fakelibvirt.HostPCIDevicesInfo()
+        self.start_compute(hostname='host1', pci_info=pci_info)
+        self.start_compute(hostname='host2', pci_info=pci_info)
+
+        extra_spec = {"pci_passthrough:alias": "%s:1" % self.PFS_ALIAS_NAME}
+        flavor_id = self._create_flavor(extra_spec=extra_spec)
+
+        validate_group_policy_called = False
+
+        def validate_group_policy(manager, instance, *args, **kwargs):
+            nonlocal validate_group_policy_called
+            if validate_group_policy_called:
+                # FIXME(johngarbutt): This is bug 1860555, it should be 1.
+                self.assertEqual(2, len(instance.pci_devices))
+            else:
+                self.assertEqual(1, len(instance.pci_devices))
+                validate_group_policy_called = True
+                raise exception.RescheduledException(
+                    instance_uuid='fake-uuid',
+                    reason='Tests: affinity validation has to fail once')
+
+        with mock.patch(
+                ('nova.compute.manager.ComputeManager.'
+                 '_validate_instance_group_policy'),
+                side_effect=validate_group_policy):
+            server = self._create_server(flavor_id=flavor_id, networks='none')
+
+        ctxt = context.get_admin_context()
+        pci_devices = objects.PciDeviceList.get_by_instance_uuid(
+            ctxt, server['id'])
+        # an additional check we have proper PCI device count in DB
+        self.assertEqual(1, len(pci_devices))
+
+
 class PCIServersWithPreferredNUMATest(_PCIServersTestBase):
 
     ALIAS_NAME = 'a1'