Add urgent argument to jitter.

message.c

@@ -373,7 +373,7 @@ flushbuf(struct network *net)
 static void
 schedule_flush(struct network *net)
 {
-    int msecs = jitter(net);
+    int msecs = jitter(net, 0);
     if(net->flush_timeout.tv_sec != 0 &&
        timeval_minus_msec(&net->flush_timeout, &now) < msecs)
         return;

network.c

@@ -108,9 +108,12 @@ update_hello_interval(struct network *net)
 /* This should be no more than half the hello interval, so that hellos
    aren't sent late.  The result is in milliseconds. */
 unsigned int
-jitter(struct network *net)
+jitter(struct network *net, int urgent)
 {
     unsigned interval = net->hello_interval;
+    if(urgent)
+        interval = MIN(interval, 100);
+    else
         interval = MIN(interval, 2000);
     return (interval / 2 + random() % interval) / 4;
 }

network.h

@@ -54,7 +54,7 @@ extern int numnets;
 struct network *add_network(char *ifname);
 int network_idle(struct network *net);
 int update_hello_interval(struct network *net);
-unsigned int jitter(struct network *net);
+unsigned int jitter(struct network *net, int urgent);
 unsigned int update_jitter(struct network *net, int urgent);
 void delay_jitter(struct timeval *time, struct timeval *timeout, int msecs);
 int network_up(struct network *net, int up);