neutron中的QOS实现源码-ml2中的实现

ml2中实现qos主要有三个文件，managers.py、plugin.py和rpc.py三个文件。

managers.py

在managers.py中，MechanismManager类主要实现了qos功能，supported_qos_rule_types()方法来让drivers决定实现相应的qos rule

    def supported_qos_rule_types(self):
        if not self.ordered_mech_drivers:
            return []

        rule_types = set(qos_consts.VALID_RULE_TYPES)
        binding_driver_found = False

        # Recalculate on every call to allow drivers determine supported rule
        # types dynamically
        for driver in self.ordered_mech_drivers:
            driver_obj = driver.obj
            if driver_obj._supports_port_binding:
                binding_driver_found = True
                if hasattr(driver_obj, 'supported_qos_rule_types'):
                    new_rule_types = \
                        rule_types & set(driver_obj.supported_qos_rule_types)
                    dropped_rule_types = new_rule_types - rule_types
                    if dropped_rule_types:
                        LOG.info(
                            _LI("%(rule_types)s rule types disabled for ml2 "
                                "because %(driver)s does not support them"),
                            {'rule_types': ', '.join(dropped_rule_types),
                             'driver': driver.name})
                    rule_types = new_rule_types
                else:
                    # at least one of drivers does not support QoS, meaning
                    # there are no rule types supported by all of them
                    LOG.warn(
                        _LW("%s does not support QoS; "
                            "no rule types available"),
                        driver.name)
                    return []

        if binding_driver_found:
            rule_types = list(rule_types)
        else:
            rule_types = []
        LOG.debug("Supported QoS rule types "
                  "(common subset for all mech drivers): %s", rule_types)
        return rule_types

plugin.py

主要实现了Ml2Plugin类，该类继承了多个不同的父类，这个类是比较重要的类，主要是对network、subnet和port进行增删改查的操作，但是在qos这一块涉及的并不多。

    def supported_qos_rule_types(self):
        return self.mechanism_manager.supported_qos_rule_types

另外，在方法update_network()和update_port()中设置qos。

def update_network(self, context, id, network):

           ... ...

           need_network_update_notify = (
           qos_consts.QOS_POLICY_ID in net_data and
           original_network[qos_consts.QOS_POLICY_ID] !=
           updated_network[qos_consts.QOS_POLICY_ID])

           ... ...

def update_port(self, context, id, port):

           ... ...

           if (qos_consts.QOS_POLICY_ID in attrs and
           original_port[qos_consts.QOS_POLICY_ID] !=
           updated_port[qos_consts.QOS_POLICY_ID]):
           need_port_update_notify = True

           ... ...

rpc.py

在L版中，rpc.py中有关qos的内容比较少，主要将qos policy和其他的network、port和mac等信息放到一个entry中进行RPC通信。

        network_qos_policy_id = port_context.network._network.get(
            qos_consts.QOS_POLICY_ID)
        entry = {'device': device,
                 'network_id': port['network_id'],
                 'port_id': port['id'],
                 'mac_address': port['mac_address'],
                 'admin_state_up': port['admin_state_up'],
                 'network_type': segment[api.NETWORK_TYPE],
                 'segmentation_id': segment[api.SEGMENTATION_ID],
                 'physical_network': segment[api.PHYSICAL_NETWORK],
                 'fixed_ips': port['fixed_ips'],
                 'device_owner': port['device_owner'],
                 'allowed_address_pairs': port['allowed_address_pairs'],
                 'port_security_enabled': port.get(psec.PORTSECURITY, True),
                 'qos_policy_id': port.get(qos_consts.QOS_POLICY_ID),
                 'network_qos_policy_id': network_qos_policy_id,
                 'profile': port[portbindings.PROFILE]}