Comment 2 for bug 1381238

Reviewed: https://review.openstack.org/128131
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=9902400039018d77aa3034147cfb24ca4b2353f6
Submitter: Jenkins
Branch: master

commit 9902400039018d77aa3034147cfb24ca4b2353f6
Author: rajeev <email address hidden>
Date: Mon Oct 13 16:25:36 2014 -0400

    Fix race condition on processing DVR floating IPs

    Fip namespace and agent gateway port can be shared by multiple dvr routers.
    This change uses a set as the control variable for these shared resources
    and ensures that Test and Set operation on the control variable are
    performed atomically so that race conditions do not occur among
    multiple threads processing floating IPs.
    Limitation: The scope of this change is limited to addressing the race
    condition described in the bug report. It may not address other issues
    such as pre-existing issue with handling of DVR floatingips on agent
    restart.

    closes-bug: #1381238

    Change-Id: I6dc2b7bad6e8ddbaa86c1f7a1e2028aeacc3afef