pi-ansible/roles/os_config/tasks/reboot.yml

# vim: ft=yaml.ansible
---
- name: Check if reboot is needed
  stat:
    path: /var/run/reboot-required
  register: needs_reboot

- name: Reboot host
  reboot:
    connect_timeout: 60
  when: needs_reboot.stat.exists or
        (force_reboot is defined and force_reboot)