reset rto timer on fast retransmission (see task #13757, patch by Joel Cunningham)

CHANGELOG

@@ -302,6 +302,9 @@ HISTORY
 
   ++ Bugfixes:
 
+  2013-03-16: Joel Cunningham
+  * tcp_out.c: reset rto timer on fast retransmission
+
   2016-03-16: Deomid Ryabkov
   * tcp_out.c: fixed bug #46384 Segment size calculation bug with MSS != TCP_MSS
 

src/core/tcp_out.c

@@ -1185,7 +1185,7 @@ tcp_output_segment(struct tcp_seg *seg, struct tcp_pcb *pcb)
 
   /* Set retransmission timer running if it is not currently enabled
      This must be set before checking the route. */
-  if (pcb->rtime == -1) {
+  if (pcb->rtime < 0) {
     pcb->rtime = 0;
   }
 
@@ -1460,6 +1460,9 @@ tcp_rexmit_fast(struct tcp_pcb *pcb)
 
     pcb->cwnd = pcb->ssthresh + 3 * pcb->mss;
     pcb->flags |= TF_INFR;
+
+    /* Reset the retransmission timer to prevent immediate rto retransmissions */
+    pcb->rtime = 0;
   }
 }