scheduler: Remove 'USES_ALLOCATION_CANDIDATES'

There is only one scheduler driver now. This variable is no longer
necessary.

We remove a couple of test that validated behavior for scheduler drivers
that didn't support allocation candidates (there are none) and update
the test for the 'nova-manage placement heal_allocations' command to
drop allocations instead of relying on them not being created.

Change-Id: I64dc67e2bacd7a6c86153db5ae983dfb54bd40eb
Signed-off-by: Stephen Finucane <stephenfin@redhat.com>

3 files changed, 0 insertions, 127 deletions

diff --git a/nova/tests/functional/regressions/test_bug_1671648.py b/nova/tests/functional/regressions/test_bug_1671648.py
index f382fc9795..b7f148cd76 100644
--- a/nova/tests/functional/regressions/test_bug_1671648.py
+++ b/nova/tests/functional/regressions/test_bug_1671648.py
@@ -135,16 +135,3 @@ class TestRetryBetweenComputeNodeBuilds(test.TestCase):
 
         # Assert that we retried.
         self.assertEqual(2, self.attempts)
-
-
-class TestRetryBetweenComputeNodeBuildsNoAllocations(
-        TestRetryBetweenComputeNodeBuilds):
-    """Tests the reschedule scenario using a scheduler driver which does
-    not use Placement.
-    """
-    def setUp(self):
-        super(TestRetryBetweenComputeNodeBuildsNoAllocations, self).setUp()
-        # We need to mock the FilterScheduler to not use Placement so that
-        # allocations won't be created during scheduling.
-        self.scheduler_service.manager.driver.USES_ALLOCATION_CANDIDATES = \
-            False
diff --git a/nova/tests/functional/regressions/test_bug_1741125.py b/nova/tests/functional/regressions/test_bug_1741125.py
index 72d69b8e9c..3f5da03043 100644
--- a/nova/tests/functional/regressions/test_bug_1741125.py
+++ b/nova/tests/functional/regressions/test_bug_1741125.py
@@ -78,17 +78,3 @@ class TestServerResizeReschedule(integrated_helpers.ProviderUsageBaseTestCase):
                 'VERIFY_RESIZE')
         self.assertEqual(self.flavor2['name'],
                          server['flavor']['original_name'])
-
-
-class TestServerResizeRescheduleWithNoAllocations(
-        TestServerResizeReschedule):
-    """Tests the reschedule scenario using a scheduler driver which does not
-    use Placement.
-    """
-
-    def setUp(self):
-        super(TestServerResizeRescheduleWithNoAllocations, self).setUp()
-        # We need to mock the FilterScheduler to not use Placement so that
-        # allocations won't be created during scheduling.
-        self.scheduler_service.manager.driver.USES_ALLOCATION_CANDIDATES = \
-            False
diff --git a/nova/tests/functional/regressions/test_bug_1741307.py b/nova/tests/functional/regressions/test_bug_1741307.py
deleted file mode 100644
index a23f6cc185..0000000000
--- a/nova/tests/functional/regressions/test_bug_1741307.py
+++ /dev/null
@@ -1,100 +0,0 @@
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-#
-#    http://www.apache.org/licenses/LICENSE-2.0
-#
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-
-from nova import test
-from nova.tests import fixtures as nova_fixtures
-from nova.tests.functional import fixtures as func_fixtures
-from nova.tests.functional import integrated_helpers
-
-
-class TestResizeWithNoAllocationScheduler(
-        test.TestCase, integrated_helpers.InstanceHelperMixin):
-    """Regression tests for bug #1741307
-
-    Some scheduler drivers, like the old CachingScheduler driver, do not use
-    Placement to make claims (allocations) against compute nodes during
-    scheduling like the FilterScheduler does.
-    During a cold migrate / resize, the FilterScheduler will "double up" the
-    instance allocations so the instance has resource allocations made against
-    both the source node and the chosen destination node. Conductor will then
-    attempt to "swap" the source node allocation to the migration record. If
-    using a non-Placement driver, there are no allocations for the instance on
-    the source node and conductor fails. Note that if the compute running the
-    instance was running Ocata code or older, then the compute itself would
-    create the allocations in Placement via the ResourceTracker, but once all
-    computes are upgraded to Pike or newer, the compute no longer creates
-    allocations in Placement because it assumes the scheduler is doing that,
-    which is not the case with these outlier scheduler drivers.
-
-    This is a regression test to show the failure before it's fixed and then
-    can be used to confirm the fix.
-    """
-
-    microversion = 'latest'
-
-    def setUp(self):
-        super(TestResizeWithNoAllocationScheduler, self).setUp()
-
-        self.useFixture(nova_fixtures.RealPolicyFixture())
-        self.useFixture(nova_fixtures.GlanceFixture(self))
-        self.useFixture(nova_fixtures.NeutronFixture(self))
-        self.useFixture(func_fixtures.PlacementFixture())
-
-        api_fixture = self.useFixture(nova_fixtures.OSAPIFixture(
-            api_version='v2.1'))
-
-        self.api = api_fixture.admin_api
-        self.api.microversion = self.microversion
-
-        self.start_service('conductor')
-
-        # Create two compute nodes/services.
-        for host in ('host1', 'host2'):
-            self.start_service('compute', host=host)
-
-        scheduler_service = self.start_service('scheduler')
-        # We need to mock the FilterScheduler to not use Placement so that
-        # allocations won't be created during scheduling.
-        scheduler_service.manager.driver.USES_ALLOCATION_CANDIDATES = False
-
-        flavors = self.api.get_flavors()
-        self.old_flavor = flavors[0]
-        self.new_flavor = flavors[1]
-
-    def test_resize(self):
-        # Create our server without networking just to keep things simple.
-        server_req = self._build_server(
-            image_uuid='155d900f-4e14-4e4c-a73d-069cbf4541e6',
-            flavor_id=self.old_flavor['id'],
-            networks='none')
-        server = self.api.post_server({'server': server_req})
-        server = self._wait_for_state_change(server, 'ACTIVE')
-
-        original_host = server['OS-EXT-SRV-ATTR:host']
-        target_host = 'host1' if original_host == 'host2' else 'host2'
-
-        # Issue the resize request.
-        post = {
-            'resize': {
-                'flavorRef': self.new_flavor['id']
-            }
-        }
-        self.api.post_server_action(server['id'], post)
-
-        # Poll the server until the resize is done.
-        server = self._wait_for_state_change(server, 'VERIFY_RESIZE')
-        # Assert that the server was migrated to the other host.
-        self.assertEqual(target_host, server['OS-EXT-SRV-ATTR:host'])
-        # Confirm the resize.
-        post = {'confirmResize': None}
-        self.api.post_server_action(server['id'], post,
-                                    check_response_status=[204])