infra-vm: efficiently handle hostvars during deploy and destroy

Pass only the required variables from `hostvars` for a given infra vm to
significantly reduce wait time during `kayobe infra vm provision` and
`kayobe infra vm deprovision`. Time to create and destroy a VM now take
a minute or less.

Closes-Bug: #2093255
Change-Id: I15d17f45d15c04aced0a4c0fe97e1d798ff46799

ansible/roles/infra-vms/tasks/deploy.yml

@@ -4,7 +4,7 @@
   include_role:
     name: jriguera.configdrive
   vars:
-    configdrive_os_family: "{{ vm_hostvars.infra_vm_os_family }}"
+    configdrive_os_family: "{{ vm_os_family }}"
     configdrive_uuid: "{{ vm_name | to_uuid }}"
     # Must set configdrive_instance_dir when using a loop
     # https://github.com/jriguera/ansible-role-configdrive/blob/8438592c84585c86e62ae07e526d3da53629b377/tasks/main.yml#L17
@@ -16,13 +16,10 @@
     configdrive_volume_path: "{{ image_cache_path }}"
     configdrive_config_dir_delete: False
     configdrive_resolv:
-      domain: "{{ vm_hostvars.resolv_domain | default }}"
+      domain: "{{ vm_resolv_domain | default }}"
-      search: "{{ vm_hostvars.resolv_search | default }}"
+      search: "{{ vm_resolv_search | default }}"
-      dns: "{{ vm_hostvars.resolv_nameservers | default([]) }}"
+      dns: "{{ vm_resolv_nameservers | default([]) }}"
-    configdrive_network_device_list: >
+    configdrive_network_device_list: "{{ vm_network_device_list }}"
-      {{ vm_hostvars.network_interfaces |
-          map('net_configdrive_network_device', vm_hostvars.inventory_hostname) |
-          list }}
 
 - name: "[{{ vm_name }}] Set a fact containing the configdrive image path"
   set_fact:
@@ -56,7 +53,7 @@
 - name: "[{{ vm_name }}] Stat image files"
   stat:
     path: "{{ image_cache_path }}/{{ item.image | basename }}"
-  with_items: "{{ vm_hostvars.infra_vm_volumes | selectattr('image', 'defined') }}"
+  with_items: "{{ vm_volumes | selectattr('image', 'defined') }}"
   register: image_stat_result
 
 - name: "[{{ vm_name }}] Fix image ownership"
@@ -75,7 +72,7 @@
     vm_configdrive_device: cdrom
     vm_configdrive_volume:
       name: "{{ vm_name }}-configdrive"
-      pool: "{{ vm_hostvars.infra_vm_pool }}"
+      pool: "{{ vm_pool }}"
       # Round size up to next multiple of 4096.
       capacity: "{{ (stat_result.stat.size + 4095) // 4096 * 4096 }}"
       device: "{{ vm_configdrive_device }}"
@@ -85,10 +82,10 @@
     libvirt_vm_image_cache_path: "{{ image_cache_path }}"
     libvirt_vms:
       - name: "{{ vm_name }}"
-        boot_firmware: "{{ vm_hostvars.infra_vm_boot_firmware | default }}"
+        boot_firmware: "{{ vm_boot_firmware | default }}"
-        machine: "{{ vm_hostvars.infra_vm_machine | default }}"
+        machine: "{{ vm_machine | default }}"
-        memory_mb: "{{ vm_hostvars.infra_vm_memory_mb }}"
+        memory_mb: "{{ vm_memory_mb }}"
-        vcpus: "{{ vm_hostvars.infra_vm_vcpus }}"
+        vcpus: "{{ vm_vcpus }}"
-        volumes: "{{ vm_hostvars.infra_vm_volumes + [vm_configdrive_volume] }}"
+        volumes: "{{ vm_volumes + [vm_configdrive_volume] }}"
-        interfaces: "{{ vm_hostvars.infra_vm_interfaces }}"
+        interfaces: "{{ vm_interfaces }}"
         console_log_enabled: true

ansible/roles/infra-vms/tasks/destroy.yml

@@ -6,12 +6,12 @@
   vars:
     infra_vm_configdrive_volume:
       name: "{{ vm_name }}-configdrive"
-      pool: "{{ hostvars[vm_hostvars.infra_vm_hypervisor].infra_vm_pool }}"
+      pool: "{{ vm_pool }}"
     libvirt_vms:
       - name: "{{ vm_name }}"
-        boot_firmware: "{{ vm_hostvars.infra_vm_boot_firmware | default }}"
+        boot_firmware: "{{ vm_boot_firmware | default }}"
-        memory_mb: "{{ vm_hostvars.infra_vm_memory_mb }}"
+        memory_mb: "{{ vm_memory_mb }}"
-        vcpus: "{{ vm_hostvars.infra_vm_vcpus }}"
+        vcpus: "{{ vm_vcpus }}"
-        volumes: "{{ vm_hostvars.infra_vm_volumes + [infra_vm_configdrive_volume] }}"
+        volumes: "{{ vm_volumes + [infra_vm_configdrive_volume] }}"
         state: "absent"
   become: True

ansible/roles/infra-vms/tasks/main.yml

@@ -10,8 +10,21 @@
 - name: "{{ infra_vm_action | capitalize }} infra VMs (loop)"
   include_tasks: "{{ infra_vm_action }}.yml"
   vars:
-    vm_name: "{{ vm_hostvars.infra_vm_name }}"
+    vm_name: "{{ hostvars[vm_item].infra_vm_name }}"
-    vm_hostvars: "{{ hostvars[vm_item] }}"
+    vm_os_family: "{{ hostvars[vm_item].infra_vm_os_family }}"
+    vm_resolv_domain: "{{ hostvars[vm_item].resolv_domain }}"
+    vm_resolv_search: "{{ hostvars[vm_item].resolv_search }}"
+    vm_resolv_nameservers: "{{ hostvars[vm_item].resolv_nameservers }}"
+    vm_network_device_list: "{{ hostvars[vm_item].network_interfaces |
+              map('net_configdrive_network_device', hostvars[vm_item].inventory_hostname) |
+                        list }}"
+    vm_volumes: "{{ hostvars[vm_item].infra_vm_volumes }}"
+    vm_pool: "{{ hostvars[vm_item].infra_vm_pool }}"
+    vm_boot_firmware: "{{ hostvars[vm_item].infra_vm_boot_firmware }}"
+    vm_machine: "{{ hostvars[vm_item].infra_vm_machine }}"
+    vm_memory_mb: "{{ hostvars[vm_item].infra_vm_memory_mb }}"
+    vm_vcpus: "{{ hostvars[vm_item].infra_vm_vcpus }}"
+    vm_interfaces: "{{ hostvars[vm_item].infra_vm_interfaces }}"
   loop: "{{ infra_vm_vms }}"
   when: (infra_vm_action == "deploy" and vm_name not in all_vms.list_vms) or infra_vm_action == "destroy"
   loop_control:

releasenotes/notes/improve-infra-vm-action-performance-5d8a218b75574be2.yaml

@@ -0,0 +1,6 @@
+---
+features:
+  - |
+    Deploying and destroying infrastructure VMs is now significantly faster
+    as only the required variables are passed to the relevant tasks as opposed
+    to the entire collection of hostvars for each VM.