cfm: Prevent interval fault when demand mode is enabled on one end.

This commit prevents cfm from raising 'interval' fault when demand
mode is only enabled on one end of link.

Signed-off-by: Alex Wang <alexw@nicira.com>
Signed-off-by: Ethan Jackson <ethan@nicira.com>
Acked-by: Ethan Jackson <ethan@nicira.com>

diff --git a/lib/cfm.c b/lib/cfm.c
index 4a46c05..e1866ff 100644 (file)
--- a/lib/cfm.c
+++ b/lib/cfm.c
@@ -255,9 +255,13 @@ cfm_fault_interval(struct cfm *cfm) OVS_REQUIRES(mutex)
      * as a fault (likely due to a configuration error).  Thus we can check all
      * MPs at once making this quite a bit simpler.
      *
-     * According to the specification we should check when (ccm_interval_ms *
-     * 3.5)ms have passed. */
-    return (cfm->ccm_interval_ms * 7) / 2;
+     * When cfm is not in demand mode, we check when (ccm_interval_ms * 3.5) ms
+     * have passed.  When cfm is in demand mode, we check when
+     * (MAX(ccm_interval_ms, 500) * 3.5) ms have passed.  This ensures that
+     * ovs-vswitchd has enough time to pull statistics from the datapath. */
+
+    return (MAX(cfm->ccm_interval_ms, cfm->demand ? 500 : cfm->ccm_interval_ms)
+            * 7) / 2;
 }
 
 static uint8_t
@@ -611,7 +615,6 @@ cfm_configure(struct cfm *cfm, const struct cfm_settings *s)
     }
 
     if (s->extended && s->demand) {
-        interval_ms = MAX(interval_ms, 500);
         if (!cfm->demand) {
             cfm->demand = true;
             cfm->rx_packets = cfm_rx_packets(cfm);

diff --git a/tests/automake.mk b/tests/automake.mk
index f531bf9..f15dcf5 100644 (file)
--- a/tests/automake.mk
+++ b/tests/automake.mk
@@ -22,6 +22,7 @@ TESTSUITE_AT = \
        tests/odp.at \
        tests/multipath.at \
        tests/bfd.at \
+       tests/cfm.at \
        tests/lacp.at \
        tests/learn.at \
        tests/vconn.at \

diff --git a/tests/cfm.at b/tests/cfm.at
new file mode 100644 (file)
index 0000000..638e03f
--- /dev/null
+++ b/tests/cfm.at
@@ -0,0 +1,57 @@
+AT_BANNER([cfm])
+
+m4_define([CFM_CHECK_EXTENDED], [
+AT_CHECK([ovs-appctl cfm/show $1 | sed -e '/next CCM tx:/d' | sed -e '/next fault check:/d' | sed -e  '/recv since check:/d'],[0],
+[dnl
+---- $1 ----
+MPID $2: extended
+       average health: $3
+       opstate: $4
+       remote_opstate: $5
+       interval: $6
+Remote MPID $7
+       opstate: $8
+])
+])
+
+# test cfm under demand mode.
+AT_SETUP([cfm - demand mode])
+#Create 2 bridges connected by patch ports and enable BFD
+OVS_VSWITCHD_START([add-br br1 -- \
+                    set bridge br1 datapath-type=dummy \
+                    other-config:hwaddr=aa:55:aa:56:00:00 -- \
+                    add-port br1 p1 -- set Interface p1 type=patch \
+                    options:peer=p0 -- \
+                    add-port br0 p0 -- set Interface p0 type=patch \
+                    options:peer=p1 -- \
+                    set Interface p0 cfm_mpid=1 other_config:cfm_interval=300 other_config:cfm_extended=true -- \
+                    set Interface p1 cfm_mpid=2 other_config:cfm_interval=300 other_config:cfm_extended=true ])
+
+ovs-appctl time/stop
+# wait for a while to stablize cfm.
+for i in `seq 0 100`; do ovs-appctl time/warp 100; done
+CFM_CHECK_EXTENDED([p0], [1], [100], [up], [up], [300ms], [2], [up])
+CFM_CHECK_EXTENDED([p1], [2], [100], [up], [up], [300ms], [1], [up])
+
+# turn on demand mode on one end.
+AT_CHECK([ovs-vsctl set interface p0 other_config:cfm_demand=true])
+
+# cfm should never go down.
+for i in `seq 0 100`
+do
+    ovs-appctl time/warp 100
+    CFM_CHECK_EXTENDED([p0], [1], [100], [up], [up], [300ms], [2], [up])
+    CFM_CHECK_EXTENDED([p1], [2], [100], [up], [up], [300ms], [1], [up])
+done
+
+# turn on demand mode on the other end.
+AT_CHECK([ovs-vsctl set interface p1 other_config:cfm_demand=true])
+for i in `seq 0 100`
+do
+    ovs-appctl time/warp 100
+    CFM_CHECK_EXTENDED([p0], [1], [100], [up], [up], [300ms], [2], [up])
+    CFM_CHECK_EXTENDED([p1], [2], [100], [up], [up], [300ms], [1], [up])
+done
+
+OVS_VSWITCHD_STOP
+AT_CLEANUP

diff --git a/tests/testsuite.at b/tests/testsuite.at
index c9bcad9..9f261a1 100644 (file)
--- a/tests/testsuite.at
+++ b/tests/testsuite.at
@@ -68,6 +68,7 @@ m4_include([tests/ovsdb-macros.at])
 m4_include([tests/ofproto-macros.at])
 
 m4_include([tests/bfd.at])
+m4_include([tests/cfm.at])
 m4_include([tests/lacp.at])
 m4_include([tests/library.at])
 m4_include([tests/heap.at])

diff --git a/vswitchd/vswitch.xml b/vswitchd/vswitch.xml
index 4b42ec7..5fd5b3b 100644 (file)
--- a/vswitchd/vswitch.xml
+++ b/vswitchd/vswitch.xml
@@ -2142,8 +2142,9 @@
           <ul>
             <li>
               To ensure that ovs-vswitchd has enough time to pull statistics
-              from the datapath, the minimum
-              <ref column="other_config" key="cfm_interval"/> is 500ms.
+              from the datapath, the fault detection interval is set to
+              3.5 * MAX(<ref column="other_config" key="cfm_interval"/>, 500)
+              ms.
             </li>
 
             <li>