Big Switch: servermanager consistency hash doesn't work in HA deployments

[Kevin Benton]

The Big Switch servermanager records the consistency hash to the database every time it gets updated but it does not retrieve the latest value from the database whenever it includes it in an HTTP request. This is fine in single neutron server deployments because the cached version on the object is always the latest, but this isn't always the case in HA deployments where another server updates the consistency DB.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/98949

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/98949
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=09e706b210513968cac2bad78fe81ee9cbb5b5be
Submitter: Jenkins
Branch: master

commit 09e706b210513968cac2bad78fe81ee9cbb5b5be
Author: Kevin Benton <email address hidden>
Date: Fri Jun 6 14:15:46 2014 -0700

    Big Switch: Lock consistency table for REST calls

    Adds a new class to hold an SQL table lock throughout
    a REST call to prevent servers in an HA deployment from
    using a stale consistency hash value.

    Also passes the current context down to the server manager
    for every request since the consistency hash will need to
    be read from the database instead of from a variable on the
    server pool object.

    Closes-Bug: #1328331
    Change-Id: I5f8402c076d7732742c0ae4d9b9d6833d42a0b7b

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/icehouse
Review: https://review.openstack.org/109145

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/109145
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=72edc1392232963b05dac7a97cb2a18368b25b34
Submitter: Jenkins
Branch: stable/icehouse

commit 72edc1392232963b05dac7a97cb2a18368b25b34
Author: Kevin Benton <email address hidden>
Date: Fri Jun 6 14:15:46 2014 -0700

    Big Switch: Lock consistency table for REST calls

    Adds a new class to hold an SQL table lock throughout
    a REST call to prevent servers in an HA deployment from
    using a stale consistency hash value.

    Also passes the current context down to the server manager
    for every request since the consistency hash will need to
    be read from the database instead of from a variable on the
    server pool object.

    Conflicts:

     neutron/plugins/bigswitch/plugin.py
     neutron/tests/unit/bigswitch/test_servermanager.py

    Closes-Bug: #1328331
    Change-Id: I5f8402c076d7732742c0ae4d9b9d6833d42a0b7b
    (cherry picked from commit 09e706b210513968cac2bad78fe81ee9cbb5b5be)