nicira plugin: metadata access network management makes unnecessary calls to backend

[Salvatore Orlando]

The following operation:

https://github.com/openstack/quantum/blob/master/quantum/plugins/nicira/common/metadata_access.py#L124

is aimed at understanding wheter ports are already configured on the router.
It is executed with an elevated context in order to take into account 'provider router' use case.
However, since it is a plugin call, it goes all the way down to the backend NVP API.

The device_id filter is not applied to the backend API call, and therefore this can cause a very large query on the NVP platform.

This particular issue can be easily fixed by avoiding backend access at all, as it's not necessary.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/28317
Committed: http://github.com/openstack/quantum/commit/0fee496538a36e7db5b7e2c7e5bbd5cff2aedd53
Submitter: Jenkins
Branch: master

commit 0fee496538a36e7db5b7e2c7e5bbd5cff2aedd53
Author: Salvatore Orlando <email address hidden>
Date: Mon May 6 17:33:44 2013 +0200

    Fetch routers ports for metadata access from DB

    Bug 1176963

    There is no need to retrieve the ports from the NVP backend, so
    a DB query will be enough.

    Change-Id: If3529cc5694434e8cdc9d21a4043f94212146d2d

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/grizzly
Review: https://review.openstack.org/28937

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/28937
Committed: http://github.com/openstack/quantum/commit/cd06e212c6320cb9394a50ed0327c464d7140b49
Submitter: Jenkins
Branch: stable/grizzly

commit cd06e212c6320cb9394a50ed0327c464d7140b49
Author: Salvatore Orlando <email address hidden>
Date: Mon May 6 17:33:44 2013 +0200

    Fetch routers ports for metadata access from DB

    Bug 1176963

    There is no need to retrieve the ports from the NVP backend, so
    a DB query will be enough.

    Change-Id: If3529cc5694434e8cdc9d21a4043f94212146d2d
    (cherry picked from commit 0fee496538a36e7db5b7e2c7e5bbd5cff2aedd53)