[ovs-dev] [PATCH v3] ovn-controller: Fix duplicated flow add attempts in table 32.

[Han Zhou]

In commit 475f0a2c it introduced a priority 150 flow for filtering
the sending of traffic received from vxlan tunnels back out tunnels.
However, it added the flow for every remote port processing, which
results in continuous logs about duplicated flows. We only need to
install this flow once per physical_run() loop iteration.

Signed-off-by: Han Zhou <zhouhan at gmail.com>
Acked-by: Darrell Ball <dball at vmware.com>
---

Notes:
    v1 -> v2: update commit message according to Darrell's comments.
    v2 -> v3: update test case.

 ovn/controller/physical.c | 47 ++++++++++++++++++++++++-----------------------
 tests/ovn.at              |  5 +++++
 2 files changed, 29 insertions(+), 23 deletions(-)

diff --git a/ovn/controller/physical.c b/ovn/controller/physical.c
index 48adb78..3b653dd 100644
--- a/ovn/controller/physical.c
+++ b/ovn/controller/physical.c
@@ -465,33 +465,16 @@ consider_port_binding(enum mf_field_id mff_ovn_geneve,
     } else {
         /* Remote port connected by tunnel */
 
-        /* Table 32, priority 150 and 100.
+        /* Table 32, priority 100.
          * ===============================
          *
-         * Priority 150 is for packets received from a VXLAN tunnel
-         * which get resubmitted to OFTABLE_LOG_INGRESS_PIPELINE due to
-         * lack of needed metadata in VXLAN, explicitly skip sending
-         * back out any tunnels and resubmit to table 33 for local
-         * delivery.
-         *
-         * Priority 100 is for all other traffic which need to be sent
-         * to a remote hypervisor.  Each flow matches an output port
-         * that includes a logical port on a remote hypervisor, and
-         * tunnels the packet to that hypervisor.
+         * Priority 100 is for traffic that needs to be sent to a remote
+         * hypervisor.  Each flow matches an output port that includes a
+         * logical port on a remote hypervisor, and tunnels the packet to
+         * that hypervisor.
          */
         match_init_catchall(&match);
         ofpbuf_clear(ofpacts_p);
-        match_set_reg_masked(&match, MFF_LOG_FLAGS - MFF_REG0,
-                             MLF_RCV_FROM_VXLAN, MLF_RCV_FROM_VXLAN);
-
-        /* Resubmit to table 33. */
-        put_resubmit(OFTABLE_LOCAL_OUTPUT, ofpacts_p);
-        ofctrl_add_flow(flow_table, OFTABLE_REMOTE_OUTPUT, 150, &match,
-                        ofpacts_p);
-
-
-        match_init_catchall(&match);
-        ofpbuf_clear(ofpacts_p);
 
         /* Match MFF_LOG_DATAPATH, MFF_LOG_OUTPORT. */
         match_set_metadata(&match, htonll(dp_key));
@@ -870,12 +853,30 @@ physical_run(struct controller_ctx *ctx, enum mf_field_id mff_ovn_geneve,
         }
     }
 
+    /* Table 32, priority 150.
+     * ===============================
+     *
+     * Priority 150 is for packets received from a VXLAN tunnel
+     * which get resubmitted to OFTABLE_LOG_INGRESS_PIPELINE due to
+     * lack of needed metadata in VXLAN, explicitly skip sending
+     * back out any tunnels and resubmit to table 33 for local
+     * delivery.
+     */
+    struct match match;
+    match_init_catchall(&match);
+    ofpbuf_clear(&ofpacts);
+    match_set_reg_masked(&match, MFF_LOG_FLAGS - MFF_REG0,
+                         MLF_RCV_FROM_VXLAN, MLF_RCV_FROM_VXLAN);
+
+    /* Resubmit to table 33. */
+    put_resubmit(OFTABLE_LOCAL_OUTPUT, &ofpacts);
+    ofctrl_add_flow(flow_table, OFTABLE_REMOTE_OUTPUT, 150, &match, &ofpacts);
+
     /* Table 32, Priority 0.
      * =======================
      *
      * Resubmit packets that are not directed at tunnels or part of a
      * multicast group to the local output table. */
-    struct match match;
     match_init_catchall(&match);
     ofpbuf_clear(&ofpacts);
     put_resubmit(OFTABLE_LOCAL_OUTPUT, &ofpacts);
diff --git a/tests/ovn.at b/tests/ovn.at
index 628d3c8..b852665 100644
--- a/tests/ovn.at
+++ b/tests/ovn.at
@@ -1058,6 +1058,11 @@ ovn_populate_arp
 # XXX This should be more systematic.
 sleep 1
 
+# Make sure there is no attempt to adding duplicated flows by ovn-controller
+AT_FAIL_IF([test -n "`grep duplicate hv1/ovn-controller.log`"])
+AT_FAIL_IF([test -n "`grep duplicate hv2/ovn-controller.log`"])
+AT_FAIL_IF([test -n "`grep duplicate hv3/ovn-controller.log`"])
+
 # Given the name of a logical port, prints the name of the hypervisor
 # on which it is located.
 vif_to_hv() {
-- 
2.1.0