Add separate variables for control plane nodes

inventory/byo/hosts.origin.example

@@ -791,9 +791,13 @@ openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true',
 # Upgrade Control
 #
 # By default nodes are upgraded in a serial manner one at a time and all failures
-# are fatal
+# are fatal, one set of variables for normal nodes, one set of variables for
+# nodes that are part of control plane as the number of hosts may be different
+# in those two groups.
 #openshift_upgrade_nodes_serial=1
 #openshift_upgrade_nodes_max_fail_percentage=0
+#openshift_upgrade_control_plane_nodes_serial=1
+#openshift_upgrade_control_plane_nodes_max_fail_percentage=0
 #
 # You can specify the number of nodes to upgrade at once. We do not currently
 # attempt to verify that you have capacity to drain this many nodes at once

inventory/byo/hosts.ose.example

@@ -788,9 +788,13 @@ openshift_master_identity_providers=[{'name': 'htpasswd_auth', 'login': 'true',
 # Upgrade Control
 #
 # By default nodes are upgraded in a serial manner one at a time and all failures
-# are fatal
+# are fatal, one set of variables for normal nodes, one set of variables for
+# nodes that are part of control plane as the number of hosts may be different
+# in those two groups.
 #openshift_upgrade_nodes_serial=1
 #openshift_upgrade_nodes_max_fail_percentage=0
+#openshift_upgrade_control_plane_nodes_serial=1
+#openshift_upgrade_control_plane_nodes_max_fail_percentage=0
 #
 # You can specify the number of nodes to upgrade at once. We do not currently
 # attempt to verify that you have capacity to drain this many nodes at once

playbooks/common/openshift-cluster/upgrades/upgrade_control_plane.yml

@@ -247,8 +247,8 @@
   hosts: oo_masters_to_config:&oo_nodes_to_upgrade
   # This var must be set with -e on invocation, as it is not a per-host inventory var
   # and is evaluated early. Values such as "20%" can also be used.
-  serial: "{{ openshift_upgrade_nodes_serial | default(1) }}"
-  max_fail_percentage: "{{ openshift_upgrade_nodes_max_fail_percentage | default(0) }}"
+  serial: "{{ openshift_upgrade_control_plane_nodes_serial | default(1) }}"
+  max_fail_percentage: "{{ openshift_upgrade_control_plane_nodes_max_fail_percentage | default(0) }}"
 
   pre_tasks:
   - name: Load lib_openshift modules