Functional tests shouldn't fail if kill command will have "no such process" during cleanup

[Slawek Kaplonski]

In case when functional tests are doing cleanup and wants to kill process which don't exists, it shouldn't cause test failure.
Example of such issue: https://e64dae2a05fb8d47b133-8b2f01caaee154d496c517b9dc32a557.ssl.cf5.rackcdn.com/678905/6/check/neutron-functional/965e654/testr_results.html.gz

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/681258

[OpenStack Infra (hudson-openstack)]

Change abandoned by Slawek Kaplonski (<email address hidden>) on branch: master
Review: https://review.opendev.org/681258
Reason: Rodolfo will propose better approach to address this bug with using os.kill()

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.opendev.org/681671

[OpenStack Infra (hudson-openstack)]

Change abandoned by Rodolfo Alonso Hernandez (<email address hidden>) on branch: master
Review: https://review.opendev.org/681671
Reason: I've been testing this patch for a long time and I don't know why os.kill(), sometimes, acts like a blocking method. We can't use it if we don't rely on it.

I'll investigate the behavior of os.kill() before proposing again this patch.

I'll take care of the abandoned patches in favor of this one.

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 18.0.0.0rc1 release candidate.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.opendev.org/c/openstack/neutron/+/681258
Committed: https://opendev.org/openstack/neutron/commit/729290357b0961eb72d7b9a540b5098ab54e1a6d
Submitter: "Zuul (22348)"
Branch: master

commit 729290357b0961eb72d7b9a540b5098ab54e1a6d
Author: Slawek Kaplonski <email address hidden>
Date: Tue Sep 10 15:36:39 2019 +0200

    [tests] Don't fail if kill cmd says that process don't exists

    In e.g. functional tests, if kill command called by
    RootHelperProcess.kill() method will return error that process
    with specified PID don't exists, test should not fails.

    This patch adds handling of such case in this method and reraise
    exception always if error code is different than 1 or
    raised exception have got different error message.

    Change-Id: I92c8f74f1dd2e76141e1e024a22589e9ddc4ff57
    Closes-Bug: #1843418

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 20.0.0.0rc1 release candidate.