On Tue, Aug 3, 2021 at 4:08 PM Numan Siddique <[email protected]> wrote:
>
> On Tue, Aug 3, 2021 at 3:29 PM Han Zhou <[email protected]> wrote:
> >
> > On Tue, Jul 27, 2021 at 10:06 AM Lorenzo Bianconi <
> > [email protected]> wrote:
> > >
> > > Introduce check_pkt_larger action for ingress traffic
> > > entering the cluster from a distributed gw router port
> > > or from a gw router. This patch enables pMTU discovery
> > > for ingress traffic.
> > >
> > > Signed-off-by: Lorenzo Bianconi <[email protected]>
> >
> > Thanks for the patch. I hit a problem while rebasing on top of this patch.
> > It is committed as:
> > With the current master (already has this patch committed), the DDlog test
> > case fails (100% failure when I run it individually, but sometimes passes
> > when I run in parallel with other cases):
> > router - check packet length - icmp defrag -- ovn-northd-ddlog --
> > dp-groups=yes
> >
> > Reverting the commit (1c9e46ab5 northd: add check_pkt_larger lflows for
> > ingress traffic) makes test pass. I haven't debugged why this happened.
> >
> > And I also have a question on the patch. Please see my comment below.
> >
> > > diff --git a/northd/ovn_northd.dl b/northd/ovn_northd.dl
> > > index d1f7dbbed..838f72824 100644
> > > --- a/northd/ovn_northd.dl
> > > +++ b/northd/ovn_northd.dl
> > > @@ -4728,7 +4728,12 @@ for (&RouterPort(.lrp = lrp,
> > >       * This will save us from having to match on inport further down in
> > >       * the pipeline.
> > >       */
> > > -    var actions = "${rEG_INPORT_ETH_ADDR()} = ${lrp_networks.ea}; next;"
> > in {
> > > +    var gw_mtu = lrp.options.get_int_def("gateway_mtu", 0) in
> > > +    var mtu = gw_mtu + vLAN_ETH_HEADER_LEN() in
> > > +    var actions = "${rEG_INPORT_ETH_ADDR()} = ${lrp_networks.ea}; " ++
> > > +    if (gw_mtu > 0) {
> > > +        "${rEGBIT_PKT_LARGER()} = check_pkt_larger(${mtu}); next;"
> > > +    } else { "next;" } in {
> > >          Flow(.logical_datapath = router._uuid,
> > >               .stage            = s_ROUTER_IN_ADMISSION(),
> > >               .priority         = 50,
> > > @@ -7558,11 +7563,12 @@ Flow(.logical_datapath = lr_uuid,
> > >      var mtu = gw_mtu + vLAN_ETH_HEADER_LEN().
> > >  MeteredFlow(.logical_datapath = lr_uuid,
> > >              .stage            = s_ROUTER_IN_LARGER_PKTS(),
> > > -            .priority         = 50,
> > > -            .__match          = "inport == ${rp.json_name} && outport ==
> > ${l3dgw_port_json_name} && "
> > > -                                "ip4 && ${rEGBIT_PKT_LARGER()}",
> > > +            .priority         = 150,
> > > +            .__match          = "inport == ${rp.json_name} && ip4 && "
> > > +                                "${rEGBIT_PKT_LARGER()} &&
> > ${rEGBIT_EGRESS_LOOPBACK()} == 0",
> > >              .actions          = "icmp4_error {"
> > >                                  "${rEGBIT_EGRESS_LOOPBACK()} = 1; "
> > > +                                "${rEGBIT_PKT_LARGER()} = 0; "
> > >                                  "eth.dst = ${rp.networks.ea}; "
> > >                                  "ip4.dst = ip4.src; "
> > >                                  "ip4.src = ${first_ipv4.addr}; "
> > > @@ -7585,13 +7591,46 @@ MeteredFlow(.logical_datapath = lr_uuid,
> > >      rp in &RouterPort(.router = r),
> > >      rp.lrp != l3dgw_port,
> > >      Some{var first_ipv4} = rp.networks.ipv4_addrs.nth(0).
> > > +
> > > +MeteredFlow(.logical_datapath = lr_uuid,
> > > +            .stage            = s_ROUTER_IN_IP_INPUT(),
> > > +            .priority         = 150,
> > > +            .__match          = "inport == ${rp.json_name} && ip4 && "
> > > +                                "${rEGBIT_PKT_LARGER()} &&
> > ${rEGBIT_EGRESS_LOOPBACK()} == 0",
> > > +            .actions          = "icmp4_error {"
> > > +                                "${rEGBIT_EGRESS_LOOPBACK()} = 1; "
> > > +                                "${rEGBIT_PKT_LARGER()} = 0; "
> > > +                                "eth.dst = ${rp.networks.ea}; "
> > > +                                "ip4.dst = ip4.src; "
> > > +                                "ip4.src = ${first_ipv4.addr}; "
> > > +                                "ip.ttl = 255; "
> > > +                                "icmp4.type = 3; /* Destination
> > Unreachable. */ "
> > > +                                "icmp4.code = 4; /* Frag Needed and DF
> > was Set. */ "
> > > +                                /* Set icmp4.frag_mtu to gw_mtu */
> > > +                                "icmp4.frag_mtu = ${gw_mtu}; "
> > > +                                "next(pipeline=ingress, table=0); "
> > > +                                "};",
> > > +            .tags             = map_empty(),
> > > +            .controller_meter = r.copp.get(cOPP_ICMP4_ERR()),
> > > +            .external_ids     = stage_hint(rp.lrp._uuid)) :-
> > > +    r in &Router(._uuid = lr_uuid),
> > > +    Some{var l3dgw_port} = r.l3dgw_port,
> > > +    var l3dgw_port_json_name = json_string_escape(l3dgw_port.name),
> > > +    r.redirect_port_name != "",
> > > +    var gw_mtu = l3dgw_port.options.get_int_def("gateway_mtu", 0),
> > > +    gw_mtu > 0,
> > > +    rp in &RouterPort(.router = r),
> > > +    rp.lrp == l3dgw_port,
> > > +    Some{var first_ipv4} = rp.networks.ipv4_addrs.nth(0).
> > > +
> >
> > This flow is exactly the same as the one immediately above it, except that
> > "rp.lrp == l3dgw_port" instead of "rp.lrp != l3dgw_port". Does it mean
> > adding the flow for all LRPs, whether it is l3dgw_port or not? If so, why
> > not combine the code just by removing the "rp.lrp == l3dgw_port" or "rp.lrp
> > != l3dgw_port" check? Did I misunderstand something? Same for the ipv6 flow
> > below.
>
> I added the ddlog part of the code.  Let me check and come back.

I didn't add the code for patch 3.  But I think it is not exactly the same.
The pipeline stage is different right ?

For the condition - rp.lrp != l3dgw_port, the flow is added in the
stage - s_ROUTER_IN_LARGER_PKTS()
and for rp.lrp == l3dgw_port, it is added in the stage - s_ROUTER_IN_IP_INPUT()

Regarding the test case,  it seems to me it's flaky.  When I run the
whole test suite with -j5, almost 100% of the
time the test fails, but it passes when run individually for me.

The test case added in this patch series, does try to make sure that
both northd-c and northd-ddlog generate
the exact same flows.

Thanks
Numan

>
> Thanks
> Numan
>
> >
> > Thanks,
> > Han
> > _______________________________________________
> > dev mailing list
> > [email protected]
> > https://mail.openvswitch.org/mailman/listinfo/ovs-dev
> >
_______________________________________________
dev mailing list
[email protected]
https://mail.openvswitch.org/mailman/listinfo/ovs-dev

Reply via email to