'Notify the ceilometer with updated volume stats'

def notify_service_capabilities(self, service_name, backend, capabilities, timestamp):

    if (service_name != 'volume'):
        return
    updated = []
    capa_new = self.service_states.get(backend, {})
    timestamp = (timestamp or timeutils.utcnow())
    if (not capa_new):
        updated = self._get_updated_pools(capa_new, capabilities)
    elif (timestamp > self.service_states[backend]['timestamp']):
        updated = self._get_updated_pools(self.service_states[backend], capabilities)
        if (not updated):
            updated = self._get_updated_pools(self.service_states_last_update.get(backend, {}), self.service_states.get(backend, {}))
    if updated:
        capab_copy = dict(capabilities)
        capab_copy['timestamp'] = timestamp
        self.service_states_last_update[backend] = capab_copy
        self.get_usage_and_notify(capabilities, updated, backend, timestamp)
