I am making my own small cluster server and configuring everything through Ansible but I am a bit stuck on checking whether or not a variable has been inserted into /boot/firmware/cmdline.txt or not.

Assume group_vars/all.yml contains the following definition:

cgroup_vars:
  - 'cgroup_enable=cpuset'
  - 'cgroup_memory=1'
  - 'cgroup_enable=memory'

I load the content into a variable with the following tasks in my playbook:

  - name: Read cmdline.txt for use below.
    shell: 'cat /boot/firmware/cmdline.txt'
    register: cmdline

  - name: Get individual environmental variables from cmdline.txt
    set_fact:
      cmd_vars: "{{ cmdline.stdout | split() }}"

Output of {{ cmd_vars | to_nice_yaml }} would be something like:

  msg: |-
    - console=serial0,115200
    - console=tty1
    - root=PARTUUID=52e8c2a3-02
    - rootfstype=ext4
    - fsck.repair=yes
    - rootwait
    - cgroup_enable=cpuset
    - cgroup_memory=1
    - cgroup_enable=memory

This should leave me with two lists: cgroup_vars and cmd_vars.

How do I check that all items in cgroup_vars is found in cmd_vars?

I would prefer that the result is a new list that contains the answer if the individual item was found or not.