1 files changed, 50 insertions, 0 deletions
diff --git a/ironic/nova/scheduler/filters/exact_core_filter.py b/ironic/nova/scheduler/filters/exact_core_filter.py
new file mode 100644
index 000000000..c3ca29228
--- /dev/null
+++ b/ironic/nova/scheduler/filters/exact_core_filter.py
@@ -0,0 +1,50 @@
+# Copyright (c) 2014 OpenStack Foundation
+#
+# All Rights Reserved.
+#
+#    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.openstack.common.gettextutils import _
+from nova.openstack.common import log as logging
+from nova.scheduler import filters
+
+LOG = logging.getLogger(__name__)
+
+
+class ExactCoreFilter(filters.BaseHostFilter):
+
+    def host_passes(self, host_state, filter_properties):
+        """Return True if host has sufficient CPU cores."""
+        instance_type = filter_properties.get('instance_type')
+        if not instance_type:
+            return True
+
+        if not host_state.vcpus_total:
+            # Fail safe
+            LOG.warning(_("VCPUs not set; assuming CPU collection broken"))
+            return True
+
+        required_vcpus = instance_type['vcpus']
+        usable_vcpus = host_state.vcpus_total - host_state.vcpus_used
+
+        if required_vcpus != usable_vcpus:
+            LOG.debug(_("%(host_state)s does not have %(requested_vcpus)s "
+                        "cores of usable vcpu, it only has %(usable_vcpus)s "
+                        "cores of usable vcpu."),
+                        {'host_state': host_state,
+                        'requested_vcpus': required_vcpus,
+                        'usable_vcpus': usable_vcpus})
+            return False
+
+        return True