ofproto-dpif: Enable smooth transition between CFM and BFD.

When user switches between using CFM and BFD, there will be a short
down time before the new protocol goes up.  This can unintentionally
change the traffic pattern of the bundled ports.  To prevent this,
it is proposed that user can enable both CFM and BFD before transition,
wait for the new protocol to go up, and then disable the old protocol.

To make this scheme work, this commit modifies the port_run() in
ofproto-dpif.c, so that when both CFM and BFD are used, if either shows
correct status, the port is considered usable in the bundle.

Signed-off-by: Alex Wang <alexw@nicira.com>

diff --git a/ofproto/ofproto-dpif.c b/ofproto/ofproto-dpif.c
index 465bf53..5a64336 100644 (file)
--- a/ofproto/ofproto-dpif.c
+++ b/ofproto/ofproto-dpif.c
@@ -2957,6 +2957,8 @@ port_run(struct ofport_dpif *ofport)
     long long int carrier_seq = netdev_get_carrier_resets(ofport->up.netdev);
     bool carrier_changed = carrier_seq != ofport->carrier_seq;
     bool enable = netdev_get_carrier(ofport->up.netdev);
+    bool cfm_enable = false;
+    bool bfd_enable = false;
 
     ofport->carrier_seq = carrier_seq;
 
@@ -2966,16 +2968,20 @@ port_run(struct ofport_dpif *ofport)
         int cfm_opup = cfm_get_opup(ofport->cfm);
 
         cfm_run(ofport->cfm);
-        enable = enable && !cfm_get_fault(ofport->cfm);
+        cfm_enable = !cfm_get_fault(ofport->cfm);
 
         if (cfm_opup >= 0) {
-            enable = enable && cfm_opup;
+            cfm_enable = cfm_enable && cfm_opup;
         }
     }
 
     if (ofport->bfd) {
         bfd_run(ofport->bfd);
-        enable = enable && bfd_forwarding(ofport->bfd);
+        bfd_enable = bfd_forwarding(ofport->bfd);
+    }
+
+    if (ofport->bfd || ofport->cfm) {
+        enable = enable && (cfm_enable || bfd_enable);
     }
 
     if (ofport->bundle) {

diff --git a/tests/ofproto-dpif.at b/tests/ofproto-dpif.at
index b093998..32e282d 100644 (file)
--- a/tests/ofproto-dpif.at
+++ b/tests/ofproto-dpif.at
@@ -2689,3 +2689,84 @@ AT_CHECK([tail -1 stdout], [0], [Datapath actions: 5
 ])
 OVS_VSWITCHD_STOP
 AT_CLEANUP
+
+# Tests the bundling with various bfd and cfm configurations.
+AT_SETUP([ofproto - bundle with variable bfd/cfm config])
+OVS_VSWITCHD_START([add-br br1 -- set bridge br1 datapath-type=dummy -- \
+                    add-bond br0 br0bond p0 p2 bond-mode=active-backup -- \
+                    add-bond br1 br1bond p1 p3 bond-mode=active-backup -- \
+                    set Interface p1 type=patch options:peer=p0 ofport_request=2 -- \
+                    set Interface p3 type=patch options:peer=p2 ofport_request=4 -- \
+                    set Interface p0 type=patch options:peer=p1 ofport_request=1 -- \
+                    set Interface p2 type=patch options:peer=p3 ofport_request=3 -- \
+                    set Interface p0 bfd:enable=true bfd:min_tx=300 bfd:min_rx=300 -- \
+                    set Interface p0 cfm_mpid=1 -- \
+                    set Interface p1 bfd:enable=true bfd:min_tx=500 bfd:min_rx=500])
+
+ovs-appctl time/stop
+# advance the clock to stablize everything.
+for i in `seq 0 49`; do ovs-appctl time/warp 100; done
+# cfm/show should show 'recv' fault.
+AT_CHECK([ovs-appctl cfm/show | sed -n '/^.*fault:.*/p'], [0], [dnl
+       fault: recv
+])
+# bfd/show should show 'up'.
+AT_CHECK([ovs-appctl bfd/show | sed -n '/^.*Session State:.*/p'], [0], [dnl
+       Local Session State: up
+       Remote Session State: up
+       Local Session State: up
+       Remote Session State: up
+])
+# bond/show should show 'may-enable: true' for all slaves.
+AT_CHECK([ovs-appctl bond/show | sed -n '/^.*may_enable:.*/p'], [0], [dnl
+       may_enable: true
+       may_enable: true
+       may_enable: true
+       may_enable: true
+])
+
+# now disable the bfd on p1.
+AT_CHECK([ovs-vsctl set Interface p1 bfd:enable=false])
+# advance the clock to stablize everything.
+for i in `seq 0 49`; do ovs-appctl time/warp 100; done
+# cfm/show should show 'recv' fault.
+AT_CHECK([ovs-appctl cfm/show | sed -n '/^.*fault:.*/p'], [0], [dnl
+       fault: recv
+])
+# bfd/show should show 'down'.
+AT_CHECK([ovs-appctl bfd/show | sed -n '/^.*Session State:.*/p'], [0], [dnl
+       Local Session State: down
+       Remote Session State: down
+])
+# bond/show should show 'may-enable: false' for p0.
+AT_CHECK([ovs-appctl bond/show | sed -n '/^.*may_enable:.*/p'], [0], [dnl
+       may_enable: false
+       may_enable: true
+       may_enable: true
+       may_enable: true
+])
+
+# now enable the bfd on p1 and disable bfd on p0.
+AT_CHECK([ovs-vsctl set Interface p1 bfd:enable=true])
+AT_CHECK([ovs-vsctl set Interface p0 bfd:enable=false])
+# advance the clock to stablize everything.
+for i in `seq 0 49`; do ovs-appctl time/warp 100; done
+# cfm/show should show 'recv' fault.
+AT_CHECK([ovs-appctl cfm/show | sed -n '/^.*fault:.*/p'], [0], [dnl
+       fault: recv
+])
+# bfd/show should show 'down'.
+AT_CHECK([ovs-appctl bfd/show | sed -n '/^.*Session State:.*/p'], [0], [dnl
+       Local Session State: down
+       Remote Session State: down
+])
+# bond/show should show 'may-enable: false' for p0 and p1.
+AT_CHECK([ovs-appctl bond/show | sed -n '/^.*may_enable:.*/p'], [0], [dnl
+       may_enable: false
+       may_enable: true
+       may_enable: false
+       may_enable: true
+])
+
+OVS_VSWITCHD_STOP
+AT_CLEANUP