From 5b85997e33aa749ece94edebaaefefe71b899561 Mon Sep 17 00:00:00 2001
From: Yun Mao <yunmao@gmail.com>
Date: Thu, 24 May 2012 21:51:57 -0400
Subject: cleanup power state (partially implements bp task-management)

Removed duplicate and invalid state in power_state:
FAILED, SHUTOFF, BLOCKED
This is the first step in cleaning up nova state machine
and do better task management (bp/task-management)

http://wiki.openstack.org/VMState

Change-Id: I586b9058fada5efd468870fb187590fc0e37aa8f
---
 nova/compute/manager.py     |  3 +--
 nova/compute/power_state.py | 25 +++++++++++++++----------
 2 files changed, 16 insertions(+), 12 deletions(-)

(limited to 'nova/compute')

diff --git a/nova/compute/manager.py b/nova/compute/manager.py
index 6a0251a15..3159ffd52 100644
--- a/nova/compute/manager.py
+++ b/nova/compute/manager.py
@@ -306,7 +306,7 @@ class ComputeManager(manager.SchedulerDependentManager):
         try:
             return self.driver.get_info(instance)["state"]
         except exception.NotFound:
-            return power_state.FAILED
+            return power_state.NOSTATE
 
     def get_console_topic(self, context, **kwargs):
         """Retrieves the console host for a project on this host.
@@ -2488,7 +2488,6 @@ class ComputeManager(manager.SchedulerDependentManager):
                 continue
 
             if (vm_power_state in (power_state.NOSTATE,
-                                   power_state.SHUTOFF,
                                    power_state.SHUTDOWN,
                                    power_state.CRASHED)
                 and db_instance['vm_state'] == vm_states.ACTIVE):
diff --git a/nova/compute/power_state.py b/nova/compute/power_state.py
index c468fe6b3..6d1c00b98 100644
--- a/nova/compute/power_state.py
+++ b/nova/compute/power_state.py
@@ -18,18 +18,26 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-"""The various power states that a VM can be in."""
-
-#NOTE(justinsb): These are the virDomainState values from libvirt
+"""Power state is the state we get by calling virt driver on a particular
+domain. The hypervisor is always considered the authority on the status
+of a particular VM, and the power_state in the DB should be viewed as a
+snapshot of the VMs's state in the (recent) past. It can be periodically
+updated, and should also be updated at the end of a task if the task is
+supposed to affect power_state.
+"""
+
+# NOTE(maoy): These are *not* virDomainState values from libvirt.
+# The hex value happens to match virDomainState for backward-compatibility
+# reasons.
 NOSTATE = 0x00
 RUNNING = 0x01
-BLOCKED = 0x02
 PAUSED = 0x03
-SHUTDOWN = 0x04
-SHUTOFF = 0x05
+SHUTDOWN = 0x04  # the VM is powered off
 CRASHED = 0x06
 SUSPENDED = 0x07
-FAILED = 0x08
+
+# TODO(maoy): BUILDING state is only used in bare metal case and should
+# eventually be removed/cleaned up. NOSTATE is probably enough.
 BUILDING = 0x09
 
 # TODO(justinsb): Power state really needs to be a proper class,
@@ -38,13 +46,10 @@ BUILDING = 0x09
 _STATE_MAP = {
     NOSTATE: 'pending',
     RUNNING: 'running',
-    BLOCKED: 'blocked',
     PAUSED: 'paused',
     SHUTDOWN: 'shutdown',
-    SHUTOFF: 'shutdown',
     CRASHED: 'crashed',
     SUSPENDED: 'suspended',
-    FAILED: 'failed to spawn',
     BUILDING: 'building',
 }
 
-- 
cgit