stx-openstack: neutron netns cleanup job is deadlocking the cpu

[Thiago Paiva Brito]

Brief Description
-----------------
The neutron-netns-cleanup-cron pods are erroring out and the lack of proper management on the script is causing a high cpu consumption (>50%). This is caused because we are overwriting a default configuration for root_helper on the neutron chart.

Severity
--------
<Major: System/Feature is usable but degraded>

Steps to Reproduce
------------------
Just apply stx-openstack and look at the neutron-netns-cleanup-cron-default-* jobs. Resource consumption can be verified using top

Expected Behavior
------------------
Job should run and sleep for a whole day.

Actual Behavior
----------------
Job is looping out and consuming more than 50% of cpu

Reproducibility
---------------
100% reproducible

System Configuration
--------------------
All configurations

Branch/Pull Time/Commit
-----------------------
N/A

Last Pass
---------
N/A

Timestamp/Logs
--------------
N/A

Test Activity
-------------
Developer Testing

Workaround
----------
system helm-override-update wr-openstack neutron openstack --set conf.neutron.agent.root_helper="sudo /var/lib/openstack/bin/neutron-rootwrap /etc/neutron/rootwrap.conf"
system application-apply stx-openstack

[Thiago Paiva Brito (outbrito)]

The bug on the script itself that will prevent this from happening in case of any future misconfiguration is dealt with on https://review.opendev.org/c/openstack/openstack-helm/+/833160

This bug only covers openstack-armada-app. The aim is to remove the override that is causing the error. We override conf.neutron.agent.root_helper with just "sudo", but calling "ip netns list" with sudo causes a problem the current version of our base OS for the neutron image:

```
sh-4.2$ sudo ip netns list
sudo: unable to mkdir /run/sudo: Read-only file system

We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these three things:

    #1) Respect the privacy of others.
    #2) Think before you type.
    #3) With great power comes great responsibility.

[sudo] password for neutron:
```

Using the default call with the rootwrap that osh uses by default [1] solves the problem, so I'll remove the override.

[1] https://github.com/openstack/openstack-helm/blame/master/neutron/values.yaml#L1903

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/c/starlingx/openstack-armada-app/+/833162

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/starlingx/openstack-armada-app/+/833162
Committed: https://opendev.org/starlingx/openstack-armada-app/commit/352e34cd2aa12c0bbf8b5a06c7b621aa480f9a9b
Submitter: "Zuul (22348)"
Branch: master

commit 352e34cd2aa12c0bbf8b5a06c7b621aa480f9a9b
Author: Thiago Brito <email address hidden>
Date: Thu Mar 10 15:19:28 2022 -0300

    Fix misconfig causing neutron netns job fail

    We should be using the default rootwrap that OSH uses, not overwriting
    this with sudo. Using just sudo cause a permission problem running this
    script.

    Closes-Bug: #1964507
    Signed-off-by: Thiago Brito <email address hidden>
    Change-Id: I0b16483504fcc83020e3387b7696b55b618a0942