dpctl: Allow requesting flow misses, expirations in "monitor" command.

This makes it possible to debug problems where one wonders whether
flow misses or flow expirations are making it up to the controller.

diff --git a/utilities/dpctl.8.in b/utilities/dpctl.8.in
index e421aa2557d168b78ce8277d24a86412dc0f84aa..0ddbc7eb7210a8aea38dd4d154913096e885ce6b 100644 (file)
--- a/utilities/dpctl.8.in
+++ b/utilities/dpctl.8.in
@@ -239,13 +239,26 @@ switch's tables are removed.  See \fBFlow Syntax\fR, below, for the
 syntax of \fIflows\fR.
 
 .TP
-\fBmonitor \fIswitch\fR
+\fBmonitor \fIswitch\fR [\fImiss-len\fR [\fIsend-exp]]
 Connects to \fIswitch\fR and prints to the console all OpenFlow
 messages received.  Usually, \fIswitch\fR should specify a connection
 named on \fBsecchan\fR(8)'s \fB-l\fR or \fB--listen\fR command line
 option.
 
-This option may be useful for debugging switch implementations.
+If \fImiss-len\fR is provided, \fBdpctl\fR sends an OpenFlow ``set
+configuration'' message at connection setup time that requests
+\fImiss-len\fR bytes of each packet that misses the flow table.  The
+OpenFlow reference implementation not send these messages to the
+\fBdpctl monitor\fR client connection unless a nonzero value is
+specified on this argument.
+
+If \fIsend-exp\fR is specified as \fB1\fR, \fBdpctl\fR will also
+request to be sent flow expiration messages.  If this argument is
+omitted, or \fB0\fR is specified, then \fRdpctl\fR will not request
+flow expirations.
+
+This command may be useful for debugging switch or controller
+implementations.
 
 .TP
 \fBexecute \fIswitch command \fR[\fIarg\fR...]

diff --git a/utilities/dpctl.c b/utilities/dpctl.c
index f66f9219fe3be0e182ec043fb5c390028c6db98d..c7a17b729e948e7f098b089a161b6ce876b82ac5 100644 (file)
--- a/utilities/dpctl.c
+++ b/utilities/dpctl.c
@@ -238,7 +238,7 @@ usage(void)
            "  add-flows SWITCH FILE       add flows from FILE\n"
            "  mod-flows SWITCH FLOW       modify actions of matching FLOWs\n"
            "  del-flows SWITCH [FLOW]     delete matching FLOWs\n"
-           "  monitor SWITCH              print packets received from SWITCH\n"
+           "  monitor SWITCH MISSLEN EXP  print packets received from SWITCH\n"
            "  execute SWITCH CMD [ARG...] execute CMD with ARGS on SWITCH\n"
            "\nFor OpenFlow switches and controllers:\n"
            "  probe VCONN                 probe whether VCONN is up\n"
@@ -1321,6 +1321,17 @@ do_monitor(const struct settings *s UNUSED, int argc UNUSED, char *argv[])
     struct vconn *vconn;
 
     open_vconn(argv[1], &vconn);
+    if (argc > 2) {
+        int miss_send_len = atoi(argv[2]);
+        int send_flow_exp = argc > 3 ? atoi(argv[3]) : 0;
+        struct ofp_switch_config *osc;
+        struct ofpbuf *buf;
+
+        osc = make_openflow(sizeof *osc, OFPT_SET_CONFIG, &buf);
+        osc->flags = htons(send_flow_exp ? OFPC_SEND_FLOW_EXP : 0);
+        osc->miss_send_len = htons(miss_send_len);
+        send_openflow_buffer(vconn, buf);
+    }
     for (;;) {
         struct ofpbuf *b;
         run(vconn_recv_block(vconn, &b), "vconn_recv");
@@ -1610,7 +1621,7 @@ static struct command all_commands[] = {
     { "status", 1, 2, do_status },
 
     { "help", 0, INT_MAX, do_help },
-    { "monitor", 1, 1, do_monitor },
+    { "monitor", 1, 3, do_monitor },
     { "dump-desc", 1, 1, do_dump_desc },
     { "dump-tables", 1, 1, do_dump_tables },
     { "dump-flows", 1, 2, do_dump_flows },