Improve sack bytes accounting and testing

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

diff --git a/src/vnet/tcp/tcp.c b/src/vnet/tcp/tcp.c
index de4edfa..36d85e4 100644 (file)
--- a/src/vnet/tcp/tcp.c
+++ b/src/vnet/tcp/tcp.c
@@ -150,11 +150,30 @@ tcp_connection_del (tcp_connection_t * tc)
 void
 tcp_connection_reset (tcp_connection_t * tc)
 {
-  if (tc->state == TCP_STATE_CLOSED)
-    return;
+  switch (tc->state)
+    {
+    case TCP_STATE_SYN_RCVD:
+      /* Cleanup everything. App wasn't notified yet */
+      stream_session_delete_notify (&tc->connection);
+      tcp_connection_cleanup (tc);
+      break;
+    case TCP_STATE_SYN_SENT:
+    case TCP_STATE_ESTABLISHED:
+    case TCP_STATE_CLOSE_WAIT:
+    case TCP_STATE_FIN_WAIT_1:
+    case TCP_STATE_FIN_WAIT_2:
+    case TCP_STATE_CLOSING:
+      tc->state = TCP_STATE_CLOSED;
+
+      /* Make sure all timers are cleared */
+      tcp_connection_timers_reset (tc);
+
+      stream_session_reset_notify (&tc->connection);
+      break;
+    case TCP_STATE_CLOSED:
+      return;
+    }
 
-  tc->state = TCP_STATE_CLOSED;
-  stream_session_reset_notify (&tc->connection);
 }
 
 /**
@@ -331,7 +350,7 @@ void
 tcp_connection_init_vars (tcp_connection_t * tc)
 {
   tcp_connection_timers_init (tc);
-  tcp_set_snd_mss (tc);
+  tcp_init_mss (tc);
   scoreboard_init (&tc->sack_sb);
   tcp_cc_init (tc);
 }
@@ -546,6 +565,48 @@ format_tcp_half_open_session (u8 * s, va_list * args)
   return format (s, "%U", format_tcp_connection, tc);
 }
 
+u8 *
+format_tcp_sacks (u8 * s, va_list * args)
+{
+  tcp_connection_t *tc = va_arg (*args, tcp_connection_t *);
+  sack_block_t *sacks = tc->snd_sacks;
+  sack_block_t *block;
+  vec_foreach (block, sacks)
+  {
+    s = format (s, " start %u end %u\n", block->start - tc->irs,
+               block->end - tc->irs);
+  }
+  return s;
+}
+
+u8 *
+format_tcp_sack_hole (u8 * s, va_list * args)
+{
+  sack_scoreboard_hole_t *hole = va_arg (*args, sack_scoreboard_hole_t *);
+  s = format (s, "[%u, %u]", hole->start, hole->end);
+  return s;
+}
+
+u8 *
+format_tcp_scoreboard (u8 * s, va_list * args)
+{
+  sack_scoreboard_t *sb = va_arg (*args, sack_scoreboard_t *);
+  sack_scoreboard_hole_t *hole;
+  s = format (s, "head %u tail %u snd_una_adv %u\n", sb->head, sb->tail,
+             sb->snd_una_adv);
+  s = format (s, "sacked_bytes %u last_sacked_bytes %u", sb->sacked_bytes,
+             sb->last_sacked_bytes);
+  s = format (s, " max_byte_sacked %u\n", sb->max_byte_sacked);
+  s = format (s, "holes:\n");
+  hole = scoreboard_first_hole (sb);
+  while (hole)
+    {
+      s = format (s, "%U", format_tcp_sack_hole, hole);
+      hole = scoreboard_next_hole (sb, hole);
+    }
+  return s;
+}
+
 transport_connection_t *
 tcp_session_get_transport (u32 conn_index, u32 thread_index)
 {
@@ -560,37 +621,69 @@ tcp_half_open_session_get_transport (u32 conn_index)
   return &tc->connection;
 }
 
+/**
+ * Compute maximum segment size for session layer.
+ *
+ * Since the result needs to be the actual data length, it first computes
+ * the tcp options to be used in the next burst and subtracts their
+ * length from the connection's snd_mss.
+ */
 u16
 tcp_session_send_mss (transport_connection_t * trans_conn)
 {
   tcp_connection_t *tc = (tcp_connection_t *) trans_conn;
+
+  /* Ensure snd_mss does accurately reflect the amount of data we can push
+   * in a segment. This also makes sure that options are updated according to
+   * the current state of the connection. */
+  tcp_update_snd_mss (tc);
+
   return tc->snd_mss;
 }
 
+always_inline u32
+tcp_round_snd_space (tcp_connection_t * tc, u32 snd_space)
+{
+  if (tc->snd_wnd < tc->snd_mss)
+    {
+      return tc->snd_wnd <= snd_space ? tc->snd_wnd : 0;
+    }
+
+  /* If we can't write at least a segment, don't try at all */
+  if (snd_space < tc->snd_mss)
+    return 0;
+
+  /* round down to mss multiple */
+  return snd_space - (snd_space % tc->snd_mss);
+}
+
 /**
  * Compute tx window session is allowed to fill.
  */
 u32
 tcp_session_send_space (transport_connection_t * trans_conn)
 {
-  u32 snd_space, chunk;
+  int snd_space;
   tcp_connection_t *tc = (tcp_connection_t *) trans_conn;
 
   /* If we haven't gotten dupacks or if we did and have gotten sacked bytes
    * then we can still send */
-  if (PREDICT_TRUE (tcp_in_fastrecovery (tc) == 0
+  if (PREDICT_TRUE (tcp_in_cong_recovery (tc) == 0
                    && (tc->rcv_dupacks == 0
                        || tc->sack_sb.last_sacked_bytes)))
     {
-      chunk = tc->snd_wnd > tc->snd_mss ? tc->snd_mss : tc->snd_wnd;
       snd_space = tcp_available_snd_space (tc);
+      return tcp_round_snd_space (tc, snd_space);
+    }
 
-      /* If we can't write at least a segment, don't try at all */
-      if (chunk == 0 || snd_space < chunk)
+  if (tcp_in_recovery (tc))
+    {
+      tc->snd_nxt = tc->snd_una_max;
+      snd_space = tcp_available_wnd (tc) - tc->rtx_bytes
+       - (tc->snd_una_max - tc->snd_congestion);
+      if (snd_space <= 0 || (tc->snd_una_max - tc->snd_una) >= tc->snd_wnd)
        return 0;
-
-      /* round down to mss multiple */
-      return snd_space - (snd_space % chunk);
+      return tcp_round_snd_space (tc, snd_space);
     }
 
   /* If in fast recovery, send 1 SMSS if wnd allows */