Hi Han

Thanks for your comment.
Comments embedded below

Thanks
Xavier

On Wed, Nov 16, 2022 at 9:04 AM Han Zhou <[email protected]> wrote:

>
>
> On Mon, Nov 14, 2022 at 1:24 AM Xavier Simonart <[email protected]>
> wrote:
> >
> > In the following scenario:
> > - interface "old" is created and external_ids:iface-id is set (to lp)
> > - interface "new" is created and external_ids:iface-id is set (to same
> lp)
> > - interface "old" is deleted
> > flows related to lp were deleted.
> >
> > Note that after "new" interface is created, flows use "new" ofport.
> > The state where old and new interfaces have both external_ids:iface-id
> set at
> > the same time is "invalid", and all flows are not installed for lpold.
> >
> > Fixes: 3ae8470edc64 ("I-P: Handle runtime data changes for pflow_output
> engine.")
> > Reported-at: https://bugzilla.redhat.com/show_bug.cgi?id=2129866
> >
> > Signed-off-by: Xavier Simonart <[email protected]>
> >
> > ---
> > v2: - Use bool instead of int for binding count to better reflect only
> >       one additional binding is supported.
> >     - Fix use after free.
> >     - Remove debug logging from test case
> > v3: - Based on Dumitru's and Mark's feedback:
> >       - Support any number of interfaces bound to the same port
> >       - Use recomputes to make code simpler (this is corner case)
> >       - Added test case using three interfaces bound to te same port
> > v4: - Updated based on Ales' feedback
> >     - Also support scenario for port-types different than localport
> >     - Added test case for VIF port
> >     - Rebased on latest main
> > v5: - Updated test case based on Numan/Dumitru's feedback (hit ofport =
> 0)
> >       and added comments in code.
> >     - Rebased on latest main.
> > ---
> >  controller/binding.c |  36 ++++++++++
> >  controller/binding.h |   1 +
> >  tests/ovn.at         | 168 +++++++++++++++++++++++++++++++++++++++++++
> >  3 files changed, 205 insertions(+)
> >
> > diff --git a/controller/binding.c b/controller/binding.c
> > index c3d2b2e42..5f04b9a74 100644
> > --- a/controller/binding.c
> > +++ b/controller/binding.c
> > @@ -1866,6 +1866,7 @@ build_local_bindings(struct binding_ctx_in
> *b_ctx_in,
> >                      lbinding = local_binding_create(iface_id,
> iface_rec);
> >                      local_binding_add(local_bindings, lbinding);
> >                  } else {
> > +                    lbinding->multiple_bindings = true;
> >                      static struct vlog_rate_limit rl =
> >                          VLOG_RATE_LIMIT_INIT(1, 5);
> >                      VLOG_WARN_RL(
> > @@ -2156,6 +2157,10 @@ consider_iface_claim(const struct
> ovsrec_interface *iface_rec,
> >          lbinding = local_binding_create(iface_id, iface_rec);
> >          local_binding_add(local_bindings, lbinding);
> >      } else {
> > +        if (lbinding->iface && lbinding->iface != iface_rec) {
> > +            lbinding->multiple_bindings = true;
> > +            b_ctx_out->local_lports_changed = true;
> > +        }
> >          lbinding->iface = iface_rec;
> >      }
> >
> > @@ -2174,6 +2179,13 @@ consider_iface_claim(const struct
> ovsrec_interface *iface_rec,
> >          return true;
> >      }
> >
> > +    /* If multiple bindings to the same port, remove the "old" binding.
> > +     * This ensures that change tracking is correct.
> > +     */
> > +    if (lbinding->multiple_bindings) {
> > +        remove_related_lport(pb, b_ctx_out);
> > +    }
> > +
> >      enum en_lport_type lport_type = get_lport_type(pb);
> >      if (lport_type == LP_LOCALPORT) {
> >          return consider_localport(pb, b_ctx_in, b_ctx_out);
> > @@ -2226,6 +2238,29 @@ consider_iface_release(const struct
> ovsrec_interface *iface_rec,
> >      struct shash *binding_lports = &b_ctx_out->lbinding_data->lports;
> >
> >      lbinding = local_binding_find(local_bindings, iface_id);
> > +
> > +    if (lbinding) {
> > +        if (lbinding->multiple_bindings) {
> > +            VLOG_INFO("Multiple bindings for %s: force recompute to
> clean up",
> > +                      iface_id);
> > +            return false;
> > +        } else {
> > +            int64_t ofport = iface_rec->n_ofport ? *iface_rec->ofport :
> 0;
> > +            if (lbinding->iface != iface_rec && !ofport) {
> > +                /* If external_ids:iface-id is set within the same
> transaction
> > +                 * as adding an interface to a bridge, ovn-controller is
> > +                 * usually initially notified of ovs interface changes
> with
> > +                 * ofport == 0. If the lport was bound to a different
> interface
> > +                 * we do not want to release it.
> > +                 */
>
> Hi Xavier, I think this logic in the "else" block, if really needed,
> belongs to a separate patch.
> It looks like an optimization to the scenario when moving a logical port
> binding from one VIF to another on the same node. I guess this doesn't
> happen very often in the real world. If it happens in some corner cases, it
> shouldn't be a problem of letting it release and reclaim, right? So I
> wonder if this change is really necessary. Assume it is correct, it still
> adds some burden when reading/debugging the code. What do you think?
>
> For the rest of the patch:
> Acked-by: Han Zhou <[email protected]>
>
> This is obviously some debatable part of the code as Numan and Dumitru
already had questions around it (hence the additional comments in the code).
To support the scenario (which I agree should not be very frequent), we
can't simply remove this part w/o other changes.
When adding and binding the second interface, if we release the interface
when ofport = 0, then we lost the information that the port was bound when
we receive the ofport for the second i/f and claim it (we set
lbinding->iface to NULL in consider_iface_release and consider_iface_claim
needs another logic to detect the double binding).
> +                VLOG_DBG("Not releasing lport %s as %s was claimed "

> > +                         "and %s was never bound)", iface_id,
> lbinding->iface ?
> > +                         lbinding->iface->name : "", iface_rec->name);
> > +                return true;
> > +            }
> > +        }
> > +    }
> > +
> >      struct binding_lport *b_lport =
> >          local_binding_get_primary_or_localport_lport(lbinding);
> >      if (is_binding_lport_this_chassis(b_lport, b_ctx_in->chassis_rec)) {
> > @@ -3034,6 +3069,7 @@ local_binding_create(const char *name, const
> struct ovsrec_interface *iface)
> >      struct local_binding *lbinding = xzalloc(sizeof *lbinding);
> >      lbinding->name = xstrdup(name);
> >      lbinding->iface = iface;
> > +    lbinding->multiple_bindings = false;
> >      ovs_list_init(&lbinding->binding_lports);
> >
> >      return lbinding;
> > diff --git a/controller/binding.h b/controller/binding.h
> > index ad959a9e6..6c3a98b02 100644
> > --- a/controller/binding.h
> > +++ b/controller/binding.h
> > @@ -135,6 +135,7 @@ struct local_binding {
> >      char *name;
> >      const struct ovsrec_interface *iface;
> >      struct ovs_list binding_lports;
> > +    bool multiple_bindings;
> >  };
> >
> >  struct local_binding_data {
> > diff --git a/tests/ovn.at b/tests/ovn.at
> > index 6552681bd..7a918c639 100644
> > --- a/tests/ovn.at
> > +++ b/tests/ovn.at
> > @@ -33053,3 +33053,171 @@ check ovn-nbctl --wait=hv sync
> >  OVN_CLEANUP([hv1])
> >  AT_CLEANUP
> >  ])
> > +
> > +m4_define([MULTIPLE_OVS_INT],
> > +  [OVN_FOR_EACH_NORTHD([
> > +   AT_SETUP([ovn-controller: Multiple OVS interfaces bound to same
> logical port ($1)])
> > +   ovn_start
> > +   net_add n1
> > +
> > +   sim_add hv1
> > +   as hv1
> > +   ovs-vsctl add-br br-phys
> > +   ovn_attach n1 br-phys 192.168.0.1
> > +
> > +   get_flows()
> > +   {
> > +       cookie=${1}
> > +       ovs-ofctl dump-flows br-int | grep $cookie |
> > +           sed -e 's/duration=[[0-9.]]*s, //g' |
> > +           sed -e 's/idle_age=[[0-9]]*, //g' |
> > +           sed -e 's/n_packets=[[0-9]]*, //g' |
> > +           sed -e 's/n_bytes=[[0-9]]*, //g'
> > +   }
> > +
> > +   check ovn-nbctl ls-add ls
> > +   check ovn-nbctl lsp-add ls lp
> > +   if test X$1 != X; then
> > +       check ovn-nbctl lsp-set-type lp $1
> > +   fi
> > +   check ovn-nbctl lsp-set-addresses lp "00:00:00:01:01:02 192.168.1.2"
> > +
> > +   check ovn-nbctl lsp-add ls vm1
> > +   check ovn-nbctl lsp-set-addresses vm1 "00:00:00:01:01:11
> 192.168.1.11"
> > +   check ovs-vsctl add-port br-int vm1 -- set interface vm1
> type=internal external_ids:iface-id=vm1
> > +
> > +   check ovn-nbctl --wait=hv sync
> > +
> > +   check ovs-vsctl add-port br-int lpold -- set interface lpold
> type=internal
> > +   check ovs-vsctl set interface lpold external_ids:iface-id=lp
> > +
> > +   OVS_WAIT_UNTIL([test x$(ovn-sbctl --bare --columns _uuid find
> port_binding logical_port=lp) != x])
> > +   echo ======================================================
> > +   echo === Flows after iface-id set for the old interface ===
> > +   echo ======================================================
> > +   COOKIE=$(ovn-sbctl find port_binding logical_port=lp|grep uuid|cut
> -d: -f2| cut -c1-8 | sed 's/^\s*0\{0,8\}//')
> > +
> > +   OVS_WAIT_UNTIL([
> > +       ofport=$(ovs-vsctl --bare --columns ofport find Interface
> name=lpold)
> > +       ovs-ofctl dump-flows br-int | grep $COOKIE | grep
> "actions=output:$ofport"
> > +   ])
> > +   nb_flows=`ovs-ofctl dump-flows br-int | grep $COOKIE | wc -l`
> > +   echo $nb_flows "flows after iface-id set for old interface"
> > +
> > +   echo ======================================================
> > +   echo === Flows after iface-id set for the new interface ===
> > +   echo ======================================================
> > +   # Set external_ids:iface-id within same transaction as adding the
> port.
> > +   # This will generally cause ovn-controller to get initially notified
> of ovs interface changes with ofport == 0.
> > +   check ovs-vsctl add-port br-int lpnew -- set interface lpnew
> type=internal -- set interface lpnew external_ids:iface-id=lp
> > +   OVS_WAIT_UNTIL([
> > +       ofport=$(ovs-vsctl --bare --columns ofport find Interface
> name=lpnew)
> > +       ovs-ofctl dump-flows br-int | grep $COOKIE | grep
> "actions=output:$ofport"
> > +   ])
> > +   check test "$nb_flows" = $(ovs-ofctl dump-flows br-int | grep
> $COOKIE | wc -l)
> > +   flows_lpnew=$(get_flows $COOKIE)
> > +
> > +   echo ======================================================
> > +   echo ======= Flows after old interface is deleted =========
> > +   echo ======================================================
> > +   check ovs-vsctl del-port br-int lpold
> > +   # We do not expect changes, so let's wait for controller to get time
> to process any update
> > +   check ovn-nbctl --wait=hv sync
> > +   check test "$nb_flows" = $(ovs-ofctl dump-flows br-int | grep
> $COOKIE | wc -l)
> > +   flows_after_deletion=$(get_flows $COOKIE)
> > +   check test "$flows_lpnew" = "$flows_after_deletion"
> > +
> > +   echo ======================================================
> > +   echo ======= Flows after lptemp interface is created ====
> > +   echo ======================================================
> > +   # Set external_ids:iface-id in a different transaction as adding the
> port.
> > +   # This will generally cause ovn-controller to get notified of ovs
> interface changes with a proper ofport.
> > +   check ovs-vsctl add-port br-int lptemp -- set Interface lptemp
> type=internal
> > +   check ovs-vsctl set Interface lptemp external_ids:iface-id=lp
> > +   OVS_WAIT_UNTIL([
> > +       ofport=$(ovs-vsctl --bare --columns ofport find Interface
> name=lptemp)
> > +       ovs-ofctl dump-flows br-int | grep $COOKIE | grep
> "actions=output:$ofport"
> > +   ])
> > +   check test "$nb_flows" = $(ovs-ofctl dump-flows br-int | grep
> $COOKIE | wc -l)
> > +
> > +   echo ======================================================
> > +   echo ======= Flows after lptemp interface is deleted ======
> > +   echo ======================================================
> > +   check ovs-vsctl del-port br-int lptemp
> > +   OVS_WAIT_UNTIL([
> > +       ofport=$(ovs-vsctl --bare --columns ofport find Interface
> name=lpnew)
> > +       echo $ofport
> > +       ovs-ofctl dump-flows br-int  | grep $COOKIE
> > +       ovs-ofctl dump-flows br-int | grep $COOKIE | grep
> "actions=output:$ofport"
> > +   ])
> > +   check test "$nb_flows" = $(ovs-ofctl dump-flows br-int | grep
> $COOKIE | wc -l)
> > +   flows_after_deletion=$(get_flows $COOKIE)
> > +   check test "$flows_lpnew" = "$flows_after_deletion"
> > +
> > +   echo ======================================================
> > +   echo ======= Flows after new interface is deleted =========
> > +   echo ======================================================
> > +   check ovs-vsctl del-port br-int lpnew
> > +   OVS_WAIT_UNTIL([
> > +       nb_flows=`ovs-ofctl dump-flows br-int | grep $COOKIE | wc -l`
> > +       test "${nb_flows}" = 0
> > +   ])
> > +
> > +   echo ======================================================
> > +   echo ======= Three interfaces bound to the same port ======
> > +   echo ======================================================
> > +   check ovs-vsctl add-port br-int lpold -- set interface lpold
> type=internal
> > +   check ovs-vsctl set interface lpold external_ids:iface-id=lp
> > +   check ovs-vsctl add-port br-int lpnew -- set interface lpnew
> type=internal
> > +   check ovs-vsctl set interface lpnew external_ids:iface-id=lp
> > +
> > +   # Wait for lpnew  flows to be installed
> > +   OVS_WAIT_UNTIL([
> > +       ofport=$(ovs-vsctl --bare --columns ofport find Interface
> name=lpnew)
> > +       ovs-ofctl dump-flows br-int | grep $COOKIE | grep
> "actions=output:$ofport"
> > +   ])
> > +   flows_lpnew=$(get_flows $COOKIE)
> > +   nb_flows=`ovs-ofctl dump-flows br-int | grep $COOKIE | wc -l`
> > +
> > +   check ovs-vsctl add-port br-int lptemp -- set Interface lptemp
> type=internal
> > +   check ovs-vsctl set Interface lptemp external_ids:iface-id=lp
> > +
> > +   # Wait for lptemp  flows to be installed
> > +   OVS_WAIT_UNTIL([
> > +       ofport=$(ovs-vsctl --bare --columns ofport find Interface
> name=lptemp)
> > +       ovs-ofctl dump-flows br-int | grep $COOKIE | grep
> "actions=output:$ofport"
> > +   ])
> > +
> > +   # Delete both lpold and lptemp to go to a stable situation
> > +   check ovs-vsctl del-port br-int lptemp
> > +   check ovs-vsctl del-port br-int lpold
> > +
> > +   OVS_WAIT_UNTIL([
> > +        test 0 = $(ovs-vsctl show | grep "Port lpold" | wc -l)
> > +   ])
> > +
> > +   # Wait for correct/lpnew flows to be installed
> > +   OVS_WAIT_UNTIL([
> > +       ofport=$(ovs-vsctl --bare --columns ofport find Interface
> name=lpnew)
> > +       ovs-ofctl dump-flows br-int | grep $COOKIE | grep
> "actions=output:$ofport"
> > +   ])
> > +   check test "$nb_flows" = $(ovs-ofctl dump-flows br-int | grep
> $COOKIE | wc -l)
> > +   flows_after_deletion=$(get_flows $COOKIE)
> > +   check test "$flows_lpnew" = "$flows_after_deletion"
> > +
> > +   # Check that recompute still works
> > +   check ovn-appctl -t ovn-controller recompute
> > +   OVS_WAIT_UNTIL([
> > +       ofport=$(ovs-vsctl --bare --columns ofport find Interface
> name=lpnew)
> > +       ovs-ofctl dump-flows br-int | grep $COOKIE | grep
> "actions=output:$ofport"
> > +   ])
> > +   check test "$nb_flows" = $(ovs-ofctl dump-flows br-int | grep
> $COOKIE | wc -l)
> > +   flows_after_deletion=$(get_flows $COOKIE)
> > +   check test "$flows_lpnew" = "$flows_after_deletion"
> > +
> > +   OVN_CLEANUP([hv1])
> > +   AT_CLEANUP
> > +   ])])
> > +
> > +MULTIPLE_OVS_INT([localport])
> > +MULTIPLE_OVS_INT([])
> > --
> > 2.31.1
> >
> > _______________________________________________
> > 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