tcp: avoid fr segments less than mss if possible

[vpp.git] / src / vnet / tcp / tcp_newreno.c

diff --git a/src/vnet/tcp/tcp_newreno.c b/src/vnet/tcp/tcp_newreno.c
index c40e443..8c7e77f 100644 (file)
--- a/src/vnet/tcp/tcp_newreno.c
+++ b/src/vnet/tcp/tcp_newreno.c
@@ -14,73 +14,114 @@
  */
 
 #include <vnet/tcp/tcp.h>
+#include <vnet/tcp/tcp_inlines.h>
 
-void
+typedef struct nwreno_cfg_
+{
+  u32 ssthresh;
+} newreno_cfg_t;
+
+static newreno_cfg_t newreno_cfg = {
+  .ssthresh = 0x7FFFFFFFU,
+};
+
+static void
 newreno_congestion (tcp_connection_t * tc)
 {
   tc->ssthresh = clib_max (tcp_flight_size (tc) / 2, 2 * tc->snd_mss);
+  tc->cwnd = tc->ssthresh;
 }
 
-void
+static void
+newreno_loss (tcp_connection_t * tc)
+{
+  tc->cwnd = tcp_loss_wnd (tc);
+}
+
+static void
 newreno_recovered (tcp_connection_t * tc)
 {
   tc->cwnd = tc->ssthresh;
 }
 
-void
-newreno_rcv_ack (tcp_connection_t * tc)
+static void
+newreno_rcv_ack (tcp_connection_t * tc, tcp_rate_sample_t * rs)
 {
   if (tcp_in_slowstart (tc))
     {
-      tc->cwnd += clib_min (tc->snd_mss, tc->bytes_acked);
+      tc->cwnd += clib_min (tc->snd_mss, rs->delivered);
     }
   else
     {
       /* tc->cwnd += clib_max ((tc->snd_mss * tc->snd_mss) / tc->cwnd, 1); */
-      tcp_cwnd_accumulate (tc, tc->cwnd, tc->bytes_acked);
+      tcp_cwnd_accumulate (tc, tc->cwnd, rs->delivered);
     }
 }
 
 void
-newreno_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type)
+newreno_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type,
+                     tcp_rate_sample_t * rs)
 {
+  /* With sacks prr controls the data in flight post congestion */
+  if (PREDICT_TRUE (tcp_opts_sack_permitted (tc)))
+    return;
+
   if (ack_type == TCP_CC_DUPACK)
     {
-      if (!tcp_opts_sack_permitted (tc))
-       tc->cwnd += tc->snd_mss;
+      tc->cwnd += tc->snd_mss;
     }
   else if (ack_type == TCP_CC_PARTIALACK)
     {
-      /* RFC 6582 Sec. 3.2 */
-      if (!tcp_opts_sack_permitted (&tc->rcv_opts))
-       {
-         /* Deflate the congestion window by the amount of new data
-          * acknowledged by the Cumulative Acknowledgment field.
-          * If the partial ACK acknowledges at least one SMSS of new data,
-          * then add back SMSS bytes to the congestion window. This
-          * artificially inflates the congestion window in order to reflect
-          * the additional segment that has left the network. This "partial
-          * window deflation" attempts to ensure that, when fast recovery
-          * eventually ends, approximately ssthresh amount of data will be
-          * outstanding in the network.*/
-         tc->cwnd = (tc->cwnd > tc->bytes_acked + tc->snd_mss) ?
-           tc->cwnd - tc->bytes_acked : tc->snd_mss;
-         if (tc->bytes_acked > tc->snd_mss)
-           tc->cwnd += tc->snd_mss;
-       }
+      /* RFC 6582 Sec. 3.2
+       * Deflate the congestion window by the amount of new data
+       * acknowledged by the Cumulative Acknowledgment field.
+       * If the partial ACK acknowledges at least one SMSS of new data,
+       * then add back SMSS bytes to the congestion window. This
+       * artificially inflates the congestion window in order to reflect
+       * the additional segment that has left the network. This "partial
+       * window deflation" attempts to ensure that, when fast recovery
+       * eventually ends, approximately ssthresh amount of data will be
+       * outstanding in the network. */
+      tc->cwnd = (tc->cwnd > tc->bytes_acked + tc->snd_mss) ?
+                  tc->cwnd - tc->bytes_acked :
+                  tc->snd_mss;
+      if (tc->bytes_acked > tc->snd_mss)
+       tc->cwnd += tc->snd_mss;
     }
 }
 
-void
+static void
 newreno_conn_init (tcp_connection_t * tc)
 {
-  tc->ssthresh = tc->snd_wnd;
+  tc->ssthresh = newreno_cfg.ssthresh;
   tc->cwnd = tcp_initial_cwnd (tc);
 }
 
+static uword
+newreno_unformat_config (unformat_input_t * input)
+{
+  u32 ssthresh = 0x7FFFFFFFU;
+
+  if (!input)
+    return 0;
+
+  unformat_skip_white_space (input);
+
+  while (unformat_check_input (input) != UNFORMAT_END_OF_INPUT)
+    {
+      if (unformat (input, "ssthresh %u", &ssthresh))
+       newreno_cfg.ssthresh = ssthresh;
+      else
+       return 0;
+    }
+  return 1;
+}
+
 const static tcp_cc_algorithm_t tcp_newreno = {
   .name = "newreno",
+  .unformat_cfg = newreno_unformat_config,
   .congestion = newreno_congestion,
+  .loss = newreno_loss,
   .recovered = newreno_recovered,
   .rcv_ack = newreno_rcv_ack,
   .rcv_cong_ack = newreno_rcv_cong_ack,