Cleanup stale flows by cookie and table_id instead of just by cookie

[gao yu]

Pre-conditions: After restart neutron-ovs-agent.

After I restart neutron-ovs-agent, I found neutron cleanup stale flows only by cookie, and the cookies in different tables always be same, that means I can cleanup flows in table 20 by cookies in table 0! I think the safer way is to cleanup stale flows by cookie and table_id instead of just by cookie.
def cleanup_flows(self):
        LOG.info("Reserved cookies for %s: %s", self.br_name,
                 self.reserved_cookies)

        for table_id in self.of_tables:
            self._dump_and_clean(table_id)

def _dump_and_clean(self, table_id=None):
        cookies = set([f.cookie for f in self.dump_flows(table_id)]) - \
                      self.reserved_cookies
        for c in cookies:
            LOG.warning("Deleting flow with cookie 0x%(cookie)x",
                        {'cookie': c})
            self.uninstall_flows(cookie=c, cookie_mask=ovs_lib.UINT64_BITMASK)
 def uninstall_flows(self, table_id=None, strict=False, priority=0,
                        cookie=COOKIE_DEFAULT, cookie_mask=0,
                        match=None, active_bundle=None, **match_kwargs):
        (dp, ofp, ofpp) = self._get_dp()
        if table_id is None:
            table_id = ofp.OFPTT_ALL
......

[LIU Yulong (dragon889)]

Did you mean this work?
https://review.opendev.org/#/c/638647/14/neutron/plugins/ml2/drivers/openvswitch/agent/openflow/native/ofswitch.py@181

[Lajos Katona (lajos-katona)]

Hi, thanks for bug report, and thanks Liu for checking.
I feel that this is now more an opinion, and perhaps with some details it can be an RFE, which can be discussed on drivers meeting with the rest of the team, what do you think?

[gao yu (gaoyublack)]

To LIU:
  Yes,I think self.uninstall_flows(cookie=c, cookie_mask=ovs_lib.UINT64_BITMASK) in functin _dump_and_clean should pass table_id parameter.

[gao yu (gaoyublack)]

To Lajos:
  OK, I think it can be an RFE.The problem I found can't affect normal network function,but I think the method I prorosed is more logical.This can be discussed on drivers meeting.