Comment 1 for bug 1748394

Reviewed: https://review.openstack.org/542727
Committed: https://git.openstack.org/cgit/openstack/compute-hyperv/commit/?id=95e979d90722293916ff7163fe25f835f785f39e
Submitter: Zuul
Branch: master

commit 95e979d90722293916ff7163fe25f835f785f39e
Author: Lucian Petrut <email address hidden>
Date: Fri Feb 9 09:39:10 2018 +0200

    Lock snapshot/destroy operations

    At some point, we've removed the instance snapshot lock, allowing
    destroy requests to proceed immediately. We assumed that this
    should be fine as long as we're stopping pending WMI jobs.

    The issue is that the snapshot operation is still not fully
    preemptive. VHD related operations (e.g. copy, merge, upload to
    glance) are not preemptive at the moment, for which reason
    destroy requests will fail due to file locks.

    Unless the new 'force_destroy_instances' config option is enabled
    (disabled by default), we're locking the destroy/snapshot operations.

    This partially reverts commit
    e4208017feb92de8bfbe1c3b28d6b6e3cea7ab2c.

    Closes-Bug: #1748394

    Change-Id: I3119c5bc5a714be867af19510dfab576f354835b