Looks good. --Justin
On Jan 25, 2013, at 3:00 PM, Ben Pfaff <[email protected]> wrote: > In Open vSwitch, a "modify" or "modify_strict" flow_mod is supposed to > refresh the flow's last-modified time even if nothing else changes, because > this interpretation makes the "learn" action more useful. As commit > 308881afb (ofproto: Reinterpret meaning of OpenFlow hard timeouts with > OFPFC_MODIFY.) notes: > > I finally found a good use for hard timeouts in OpenFlow, but they > require a slight reinterpretation of the meaning of hard timeouts. > Until now, a hard timeout meant that a flow would be removed the > specified number of seconds after a flow was created. Intervening > modifications with OFPFC_MODIFY(_STRICT) had no effect on the hard > timeout; the flow would still be deleted the specified number of > seconds after its original creation. > > This commit changes the effect of OFPFC_MODIFY(_STRICT). Now, > modifying a flow resets its hard timeout counter. A flow will time out > the specified number of seconds after creation or after the last time > it is modified, whichever comes later. > > However, commit 080437614b (ofproto: Represent flow cookie changes as > operations too.) broke this behavior because it incorrectly optimized out > "modify" operations that didn't change the flow's actions or flow cookie. > This commit fixes the problem, and adds a test to prevent future > regression. > > Thanks to Amar Padmanabhan <[email protected]> for helping to track this > down. > > Bug #14538. > Reported-by: Hiroshi Tanaka <[email protected]> > CC: Amar Padmanabhan <[email protected]> > Signed-off-by: Ben Pfaff <[email protected]> > --- > ofproto/ofproto.c | 18 +++++++++--- > tests/learn.at | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 88 insertions(+), 5 deletions(-) > > diff --git a/ofproto/ofproto.c b/ofproto/ofproto.c > index bc27079..249f2d5 100644 > --- a/ofproto/ofproto.c > +++ b/ofproto/ofproto.c > @@ -3261,10 +3261,6 @@ modify_flows__(struct ofproto *ofproto, struct ofconn > *ofconn, > new_cookie = (fm->new_cookie != htonll(UINT64_MAX) > ? fm->new_cookie > : rule->flow_cookie); > - if (!actions_changed && new_cookie == rule->flow_cookie) { > - /* No change at all. */ > - continue; > - } > > op = ofoperation_create(group, rule, OFOPERATION_MODIFY, 0); > rule->flow_cookie = new_cookie; > @@ -4247,7 +4243,19 @@ ofopgroup_complete(struct ofopgroup *group) > LIST_FOR_EACH_SAFE (op, next_op, group_node, &group->ops) { > struct rule *rule = op->rule; > > - if (!op->error && !ofproto_rule_is_hidden(rule)) { > + /* We generally want to report the change to active OpenFlow flow > + monitors (e.g. NXST_FLOW_MONITOR). There are three exceptions: > + > + - The operation failed. > + > + - The affected rule is not visible to controllers. > + > + - The operation's only effect was to update rule->modified. */ > + if (!(op->error > + || ofproto_rule_is_hidden(rule) > + || (op->type == OFOPERATION_MODIFY > + && op->ofpacts > + && rule->flow_cookie == op->flow_cookie))) { > /* Check that we can just cast from ofoperation_type to > * nx_flow_update_event. */ > BUILD_ASSERT_DECL((enum nx_flow_update_event) OFOPERATION_ADD > diff --git a/tests/learn.at b/tests/learn.at > index 47c1d32..800dc14 100644 > --- a/tests/learn.at > +++ b/tests/learn.at > @@ -122,6 +122,81 @@ NXST_FLOW reply: > OVS_VSWITCHD_STOP > AT_CLEANUP > > +dnl This test checks that repeated uses of a "learn" action cause the > +dnl modified time of the learned flow to advance. Otherwise, the > +dnl learned flow will expire after its hard timeout even though it's > +dnl supposed to be refreshed. (The expiration can be hard to see since > +dnl it gets re-learned again the next time a packet appears, but > +dnl sometimes the expiration can cause temporary flooding etc.) > +AT_SETUP([learning action - learn refreshes hard_age]) > +OVS_VSWITCHD_START( > + [add-port br0 p1 -- set Interface p1 type=dummy ofport_request=1 -- \ > + add-port br0 p2 -- set Interface p2 type=dummy ofport_request=2 -- \ > + add-port br0 p3 -- set Interface p3 type=dummy ofport_request=3]) > + > +ovs-appctl time/stop > + > +# Set up flow table for MAC learning. > +AT_DATA([flows.txt], [[ > +table=0 actions=learn(table=1, hard_timeout=10, > NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[], output:NXM_OF_IN_PORT[]), resubmit(,1) > +table=1 priority=0 actions=flood > +]]) > +AT_CHECK([ovs-ofctl add-flows br0 flows.txt]) > + > +# Trace an ICMP packet arriving on port 3, to create a MAC learning entry. > +flow="in_port(3),eth(src=50:54:00:00:00:07,dst=50:54:00:00:00:05),eth_type(0x0800),ipv4(src=192.168.0.2,dst=192.168.0.1,proto=1,tos=0,ttl=64,frag=no),icmp(type=0,code=0)" > +AT_CHECK([ovs-appctl ofproto/trace br0 "$flow" -generate], [0], [stdout]) > +actual=`tail -1 stdout | sed 's/Datapath actions: //'` > + > +expected="1,2,100" > +AT_CHECK([ovs-dpctl normalize-actions "$flow" "$expected"], [0], [stdout]) > +mv stdout expout > +AT_CHECK([ovs-dpctl normalize-actions "$flow" "$actual"], [0], [expout]) > + > +# Check that the MAC learning entry appeared. > +AT_CHECK([ovs-ofctl dump-flows br0 table=1 | ofctl_strip | sort], [0], [dnl > + table=1, hard_timeout=10, dl_dst=50:54:00:00:00:07 actions=output:3 > + table=1, priority=0 actions=FLOOD > +NXST_FLOW reply: > +]) > + > +# For 25 seconds, make sure that the MAC learning entry doesn't > +# disappear as long as we refresh it every second. > +for i in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25; > do > + ovs-appctl time/warp 1000 > + AT_CHECK([ovs-appctl ofproto/trace br0 "$flow" -generate], [0], [stdout]) > + > + # Check that the entry is there. > + AT_CHECK([ovs-ofctl dump-flows br0 table=1], [0], [stdout]) > + AT_CHECK([ofctl_strip < stdout | sort], [0], [dnl > + table=1, hard_timeout=10, dl_dst=50:54:00:00:00:07 actions=output:3 > + table=1, priority=0 actions=FLOOD > +NXST_FLOW reply: > +]) > + > + if test $i != 1; then > + # Check that hard_age has appeared. We need to do this separately > + # from the above check because ofctl_strip removes it. dump-flows > + # only prints hard_age when it is different from the flow's duration > + # (that is, the number of seconds from the time it was created), > + # so we only check for it after we've refreshed the flow once. > + AT_CHECK([grep dl_dst=50:54:00:00:00:07 stdout | grep -c hard_age], > + [0], [1 > +]) > + fi > +done > + > +# Make sure that 15 seconds without refreshing makes the flow time out. > +ovs-appctl time/warp 5000 > +ovs-appctl time/warp 5000 > +ovs-appctl time/warp 5000 > + AT_CHECK([ovs-ofctl dump-flows br0 table=1 | ofctl_strip | sort], [0], > [dnl > + table=1, priority=0 actions=FLOOD > +NXST_FLOW reply: > +]) > +OVS_VSWITCHD_STOP > +AT_CLEANUP > + > AT_SETUP([learning action - TCPv4 port learning]) > OVS_VSWITCHD_START( > [add-port br0 p1 -- set Interface p1 type=dummy -- \ > -- > 1.7.2.5 > > _______________________________________________ > dev mailing list > [email protected] > http://openvswitch.org/mailman/listinfo/dev _______________________________________________ dev mailing list [email protected] http://openvswitch.org/mailman/listinfo/dev
