rbd update volume stats in wrong way

[wuyuting]

Cinder volume uses a RADOS pool to store volumes. Cinder-volume report storage stats periodically. However, rbd driver report the whole cluster stats but not the pool. The correct way is report the pool stats but not the cluster.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/166164

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/166164
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=ac219d5dd93c5c637336a9c79389fc260af65d36
Submitter: Jenkins
Branch: master

commit ac219d5dd93c5c637336a9c79389fc260af65d36
Author: wuyuting <email address hidden>
Date: Fri Mar 20 18:41:11 2015 +0800

    Rbd update volume stats in wrong way

    Cinder volume uses a RADOS pool to store volumes and
    update storage stats periodically. However, rbd driver
    reports the whole cluster stats but not the pool's. This
    is wrong. The right way is to report the pool stats but
    not the whole cluster.

    Change-Id: Ie18324ebd8b85f7b63dc034ba20857ae9e470804
    Closes-Bug: #1434441