This uses the new 'prlimit' parameter for oslo.concurrency execute
method, to set an address space limit of 1GB and CPU time limit
of 2 seconds, when running qemu-img.
This is a re-implementation of the previously reverted commit
commit da217205f5
Author: Tristan Cacqueray <tdecacqu@redhat.com>
Date: Wed Aug 5 17:17:04 2015 +0000
virt: Use preexec_fn to ulimit qemu-img info call
NOTE (kchamart) [stable/liberty]: Add a check for the presence of
'ProcessLimits' attribute (which is only present in
oslo.concurrency>=2.6.1; and a conditional check for 'prlimit' parameter
in qemu_img_info() method.
Upstream discussion[1][2] that led to merging this patch to
stable/liberty branch.
[1] http://lists.openstack.org/pipermail/openstack-dev/2016-September/104091.html
[2] http://lists.openstack.org/pipermail/openstack-dev/2016-September/104303.html
Closes-Bug: #1449062
Change-Id: I135b5242af1bfdcb0ea09a6fcda21fc03a6fbe7d
(cherry picked from commit 068d851561)