Re-use logic from StrategyBase._load_included_file in StrategyModule.run for free and linear

[sivel]

SUMMARY

Re-use logic from StrategyBase._load_included_file in StrategyModule.run for free and linear. This is the magic incantation that uses less memory and allows higher recursion for include_tasks and with much faster execution.

Before this change, with the below reproducer, ansible would fail with a recursion error at about 30 recursive include_role calls, with an average of 0.86s per include_role.

After this, I was able to get 197, with an average of 0.38s per include_role.

ISSUE TYPE

• Bugfix Pull Request

COMPONENT NAME

lib/ansible/plugins/strategy

ANSIBLE VERSION

2.4
2.5
2.6

ADDITIONAL INFORMATION

Reproducer:

playbook.yml

---
- hosts: localhost
  gather_facts: false
  vars:
    counter: 0
  tasks:
    - include_role:
        name: recursion

roles/recursion/tasks/main.yml

---
- debug:
    var: counter|int

- set_fact:
    counter: "{{ counter|int + 1 }}"

- include_role:
    name: recursion

Before (exeuction time=0m25.695s):

TASK [recursion : set_fact] ******************************************************************************************************************************************************************************************************************
ok: [localhost] => {"ansible_facts": {"counter": "30"}, "changed": false, "failed": false}

TASK [recursion : include_role] **************************************************************************************************************************************************************************************************************
ERROR! Unexpected Exception, this is probably a bug: maximum recursion depth exceeded
to see the full traceback, use -vvv

After (execution time=1m15.317s):

TASK [recursion : set_fact] ******************************************************************************************************************************************************************************************************************
ok: [localhost] => {"ansible_facts": {"counter": "197"}, "changed": false, "failed": false}

TASK [recursion : include_role] **************************************************************************************************************************************************************************************************************
ERROR! Unexpected Exception, this is probably a bug: maximum recursion depth exceeded
to see the full traceback, use -vvv

[sivel]

This also resolves the reproducer in #23609 (comment)

[jimi-c]

👍