Send full instance to scheduler live_migration.

Remove the instance_id parameter and send a full instance dict to the
live_migration method of the scheduler manager.  This cuts down on some
unnecessary database access in the scheduler.

Part of blueprint no-db-messaging.

Change-Id: Ic45105300c967c760559df2225e59e515cea8b7b

7 files changed, 32 insertions, 35 deletions

diff --git a/nova/compute/api.py b/nova/compute/api.py
index 7ff66aa93..900ab706f 100644
--- a/nova/compute/api.py
+++ b/nova/compute/api.py
@@ -1719,12 +1719,8 @@ class API(base.Base):
         """Migrate a server lively to a new host."""
         LOG.debug(_("Going to try to live migrate instance"),
                   instance=instance)
-        self.scheduler_rpcapi.live_migration(context,
-                block_migration,
-                disk_over_commit,
-                instance["id"],
-                host,
-                topic=FLAGS.compute_topic)
+        self.scheduler_rpcapi.live_migration(context, block_migration,
+                disk_over_commit, instance, host)
 
 
 class HostAPI(base.Base):
diff --git a/nova/scheduler/driver.py b/nova/scheduler/driver.py
index 36be81f48..6494957e2 100644
--- a/nova/scheduler/driver.py
+++ b/nova/scheduler/driver.py
@@ -200,13 +200,14 @@ class Scheduler(object):
         msg = _("Driver must implement schedule_run_instance")
         raise NotImplementedError(msg)
 
-    def schedule_live_migration(self, context, instance_id, dest,
-                                block_migration=False,
-                                disk_over_commit=False):
+    def schedule_live_migration(self, context, dest,
+                                block_migration=False, disk_over_commit=False,
+                                instance=None, instance_id=None):
         """Live migration scheduling method.
 
         :param context:
-        :param instance_id:
+        :param instance_id: (deprecated)
+        :param instance: instance dict
         :param dest: destination host
         :param block_migration: if true, block_migration.
         :param disk_over_commit: if True, consider real(not virtual)
@@ -217,27 +218,29 @@ class Scheduler(object):
             Then scheduler send request that host.
         """
         # Check we can do live migration
-        instance_ref = db.instance_get(context, instance_id)
-        self._live_migration_src_check(context, instance_ref)
-        self._live_migration_dest_check(context, instance_ref, dest)
-        self._live_migration_common_check(context, instance_ref, dest)
+        if not instance:
+            instance = db.instance_get(context, instance_id)
+
+        self._live_migration_src_check(context, instance)
+        self._live_migration_dest_check(context, instance, dest)
+        self._live_migration_common_check(context, instance, dest)
         self.compute_rpcapi.check_can_live_migrate_destination(context,
-                instance_ref, dest, block_migration, disk_over_commit)
+                instance, dest, block_migration, disk_over_commit)
 
         # Change instance_state
         values = {"task_state": task_states.MIGRATING}
 
         # update instance state and notify
         (old_ref, new_instance_ref) = db.instance_update_and_get_original(
-                context, instance_ref['uuid'], values)
+                context, instance['uuid'], values)
         notifications.send_update(context, old_ref, new_instance_ref,
                 service="scheduler")
 
         # Perform migration
-        src = instance_ref['host']
+        src = instance['host']
         cast_to_compute_host(context, src, 'live_migration',
                              update_db=False,
-                             instance_id=instance_id,
+                             instance_id=instance['id'],
                              dest=dest,
                              block_migration=block_migration)
 
diff --git a/nova/scheduler/manager.py b/nova/scheduler/manager.py
index ad3441593..924e5d426 100644
--- a/nova/scheduler/manager.py
+++ b/nova/scheduler/manager.py
@@ -53,7 +53,7 @@ QUOTAS = quota.QUOTAS
 class SchedulerManager(manager.Manager):
     """Chooses a host to run instances on."""
 
-    RPC_API_VERSION = '1.2'
+    RPC_API_VERSION = '1.3'
 
     def __init__(self, scheduler_driver=None, *args, **kwargs):
         if not scheduler_driver:
diff --git a/nova/scheduler/rpcapi.py b/nova/scheduler/rpcapi.py
index a553b202c..9965a162e 100644
--- a/nova/scheduler/rpcapi.py
+++ b/nova/scheduler/rpcapi.py
@@ -37,6 +37,7 @@ class SchedulerAPI(nova.openstack.common.rpc.proxy.RpcProxy):
                 - remove instance_type_id, add instance_type
                 - remove topic, it was unused
         1.2 - Remove topic from run_instance, it was unused
+        1.3 - Remove instance_id, add instance to live_migration
     '''
 
     BASE_RPC_API_VERSION = '1.0'
@@ -70,13 +71,14 @@ class SchedulerAPI(nova.openstack.common.rpc.proxy.RpcProxy):
         return self.call(ctxt, self.make_msg('show_host_resources', host=host))
 
     def live_migration(self, ctxt, block_migration, disk_over_commit,
-            instance_id, dest, topic):
+            instance, dest, topic):
         # NOTE(comstud): Call vs cast so we can get exceptions back, otherwise
         # this call in the scheduler driver doesn't return anything.
+        instance_p = jsonutils.to_primitive(instance)
         return self.call(ctxt, self.make_msg('live_migration',
                 block_migration=block_migration,
-                disk_over_commit=disk_over_commit, instance_id=instance_id,
-                dest=dest, topic=topic))
+                disk_over_commit=disk_over_commit, instance=instance_p,
+                dest=dest, topic=topic), version='1.3')
 
     def update_service_capabilities(self, ctxt, service_name, host,
             capabilities):
diff --git a/nova/tests/api/openstack/compute/contrib/test_admin_actions.py b/nova/tests/api/openstack/compute/contrib/test_admin_actions.py
index 89ac3d9a0..8da846125 100644
--- a/nova/tests/api/openstack/compute/contrib/test_admin_actions.py
+++ b/nova/tests/api/openstack/compute/contrib/test_admin_actions.py
@@ -62,9 +62,10 @@ def fake_compute_api_get(self, context, instance_id):
             'task_state': None}
 
 
-def fake_scheduler_api_live_migration(self, context, block_migration,
-                                      disk_over_commit, instance_id,
-                                      dest, topic):
+def fake_scheduler_api_live_migration(self, context, dest,
+                                      block_migration=False,
+                                      disk_over_commit=False, instance=None,
+                                      instance_id=None):
     return None
 
 
diff --git a/nova/tests/scheduler/test_rpcapi.py b/nova/tests/scheduler/test_rpcapi.py
index 20874c365..ff17d9183 100644
--- a/nova/tests/scheduler/test_rpcapi.py
+++ b/nova/tests/scheduler/test_rpcapi.py
@@ -95,7 +95,8 @@ class SchedulerRpcAPITestCase(test.TestCase):
         self._test_scheduler_api('live_migration', rpc_method='call',
                 block_migration='fake_block_migration',
                 disk_over_commit='fake_disk_over_commit',
-                instance_id='fake_id', dest='fake_dest', topic='fake_topic')
+                instance='fake_instance', dest='fake_dest', topic='fake_topic',
+                version='1.3')
 
     def test_update_service_capabilities(self):
         self._test_scheduler_api('update_service_capabilities',
diff --git a/nova/tests/scheduler/test_scheduler.py b/nova/tests/scheduler/test_scheduler.py
index 0c416dc72..3950d1ef6 100644
--- a/nova/tests/scheduler/test_scheduler.py
+++ b/nova/tests/scheduler/test_scheduler.py
@@ -403,7 +403,6 @@ class SchedulerTestCase(test.TestCase):
 
     def test_live_migration_basic(self):
         """Test basic schedule_live_migration functionality"""
-        self.mox.StubOutWithMock(db, 'instance_get')
         self.mox.StubOutWithMock(self.driver, '_live_migration_src_check')
         self.mox.StubOutWithMock(self.driver, '_live_migration_dest_check')
         self.mox.StubOutWithMock(self.driver, '_live_migration_common_check')
@@ -416,11 +415,9 @@ class SchedulerTestCase(test.TestCase):
         dest = 'fake_host2'
         block_migration = False
         disk_over_commit = False
-        instance = self._live_migration_instance()
+        instance = jsonutils.to_primitive(self._live_migration_instance())
         instance_id = instance['id']
         instance_uuid = instance['uuid']
-        db.instance_get(self.context,
-                        instance_id).AndReturn(instance)
 
         self.driver._live_migration_src_check(self.context, instance)
         self.driver._live_migration_dest_check(self.context, instance, dest)
@@ -441,14 +438,13 @@ class SchedulerTestCase(test.TestCase):
 
         self.mox.ReplayAll()
         self.driver.schedule_live_migration(self.context,
-                instance_id=instance['id'], dest=dest,
+                instance=instance, dest=dest,
                 block_migration=block_migration,
                 disk_over_commit=disk_over_commit)
 
     def test_live_migration_all_checks_pass(self):
         """Test live migration when all checks pass."""
 
-        self.mox.StubOutWithMock(db, 'instance_get')
         self.mox.StubOutWithMock(utils, 'service_is_up')
         self.mox.StubOutWithMock(db, 'service_get_all_compute_by_host')
         self.mox.StubOutWithMock(db, 'instance_get_all_by_host')
@@ -463,8 +459,6 @@ class SchedulerTestCase(test.TestCase):
         instance = jsonutils.to_primitive(self._live_migration_instance())
         instance_id = instance['id']
         instance_uuid = instance['uuid']
-        db.instance_get(self.context,
-                        instance_id).AndReturn(instance)
 
         # Source checks
         db.service_get_all_compute_by_host(self.context,
@@ -511,7 +505,7 @@ class SchedulerTestCase(test.TestCase):
 
         self.mox.ReplayAll()
         result = self.driver.schedule_live_migration(self.context,
-                instance_id=instance_id, dest=dest,
+                instance=instance, dest=dest,
                 block_migration=block_migration,
                 disk_over_commit=disk_over_commit)
         self.assertEqual(result, None)