X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvnet%2Ftcp%2Ftcp_output.c;h=7b0303f30335f31e50adef9f60430c87bc5e9083;hb=1cfcb78940580c8e3645fca0419d32f9286e942d;hp=2abc40a8cc77e18837712f1bfd7e402b2792a308;hpb=537e85deab6fd916952ff4badeda4ec5d6f1a121;p=vpp.git

diff --git a/src/vnet/tcp/tcp_output.c b/src/vnet/tcp/tcp_output.c
index 2abc40a8cc7..7b0303f3033 100644
--- a/src/vnet/tcp/tcp_output.c
+++ b/src/vnet/tcp/tcp_output.c
@@ -130,20 +130,19 @@ tcp_initial_window_to_advertise (tcp_connection_t * tc)
   return clib_min (tc->rcv_wnd, TCP_WND_MAX);
 }
 
-static void
+static inline void
 tcp_update_rcv_wnd (tcp_connection_t * tc)
 {
+  u32 available_space, wnd;
   i32 observed_wnd;
-  u32 available_space, max_fifo, wnd;
+
+  ASSERT (tc->rcv_opts.mss < transport_rx_fifo_size (&tc->connection));
 
   /*
    * Figure out how much space we have available
    */
   available_space = transport_max_rx_enqueue (&tc->connection);
-  max_fifo = transport_rx_fifo_size (&tc->connection);
-
-  ASSERT (tc->rcv_opts.mss < max_fifo);
-  if (available_space < tc->rcv_opts.mss && available_space < max_fifo >> 3)
+  if (PREDICT_FALSE (available_space < tc->rcv_opts.mss))
     available_space = 0;
 
   /*
@@ -151,13 +150,11 @@ tcp_update_rcv_wnd (tcp_connection_t * tc)
    * to compute the new window
    */
   observed_wnd = (i32) tc->rcv_wnd - (tc->rcv_nxt - tc->rcv_las);
-  if (observed_wnd < 0)
-    observed_wnd = 0;
 
   /* Bad. Thou shalt not shrink */
-  if (available_space < observed_wnd)
+  if (PREDICT_FALSE ((i32) available_space < observed_wnd))
     {
-      wnd = observed_wnd;
+      wnd = clib_max (observed_wnd, 0);
       TCP_EVT_DBG (TCP_EVT_RCV_WND_SHRUNK, tc, observed_wnd, available_space);
     }
   else
@@ -186,16 +183,6 @@ tcp_window_to_advertise (tcp_connection_t * tc, tcp_state_t state)
     return tcp_initial_window_to_advertise (tc);
 
   tcp_update_rcv_wnd (tc);
-
-  if (tc->rcv_wnd == 0)
-    {
-      tc->flags |= TCP_CONN_SENT_RCV_WND0;
-    }
-  else
-    {
-      tc->flags &= ~TCP_CONN_SENT_RCV_WND0;
-    }
-
   return tc->rcv_wnd >> tc->rcv_wscale;
 }
 
@@ -357,7 +344,7 @@ tcp_make_established_options (tcp_connection_t * tc, tcp_options_t * opts)
   if (tcp_opts_tstamp (&tc->rcv_opts))
     {
       opts->flags |= TCP_OPTS_FLAG_TSTAMP;
-      opts->tsval = tcp_time_now_w_thread (tc->c_thread_index);
+      opts->tsval = tcp_tstamp (tc);
       opts->tsecr = tc->tsval_recent;
       len += TCP_OPTION_LEN_TIMESTAMP;
     }
@@ -435,6 +422,12 @@ tcp_update_burst_snd_vars (tcp_connection_t * tc)
 		     &tc->snd_opts);
 
   tcp_update_rcv_wnd (tc);
+
+  if (tc->flags & TCP_CONN_RATE_SAMPLE)
+    tc->flags |= TCP_CONN_TRACK_BURST;
+
+  if (tc->snd_una == tc->snd_nxt)
+    tcp_cc_event (tc, TCP_CC_EVT_START_TX);
 }
 
 void
@@ -515,6 +508,11 @@ tcp_make_ack_i (tcp_connection_t * tc, vlib_buffer_t * b, tcp_state_t state,
 
   tcp_options_write ((u8 *) (th + 1), snd_opts);
   vnet_buffer (b)->tcp.connection_index = tc->c_c_index;
+
+  if (wnd == 0)
+    tcp_zero_rwnd_sent_on (tc);
+  else
+    tcp_zero_rwnd_sent_off (tc);
 }
 
 /**
@@ -535,9 +533,6 @@ void
 tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b)
 {
   tcp_make_ack_i (tc, b, TCP_STATE_ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK);
-
-  /* Reset flags, make sure ack is sent */
-  vnet_buffer (b)->tcp.flags &= ~TCP_BUF_FLAG_DUPACK;
 }
 
 /**
@@ -1145,10 +1140,18 @@ u32
 tcp_session_push_header (transport_connection_t * tconn, vlib_buffer_t * b)
 {
   tcp_connection_t *tc = (tcp_connection_t *) tconn;
+
+  if (tc->flags & TCP_CONN_TRACK_BURST)
+    {
+      tcp_bt_check_app_limited (tc);
+      tcp_bt_track_tx (tc);
+      tc->flags &= ~TCP_CONN_TRACK_BURST;
+    }
+
   tcp_push_hdr_i (tc, b, tc->snd_nxt, /* compute opts */ 0, /* burst */ 1,
 		  /* update_snd_nxt */ 1);
+
   tc->snd_una_max = seq_max (tc->snd_nxt, tc->snd_una_max);
-  ASSERT (seq_leq (tc->snd_una_max, tc->snd_una + tc->snd_wnd));
   tcp_validate_txf_size (tc, tc->snd_una_max - tc->snd_una);
   /* If not tracking an ACK, start tracking */
   if (tc->rtt_ts == 0 && !tcp_in_cong_recovery (tc))
@@ -1270,6 +1273,28 @@ tcp_timer_delack_handler (u32 index)
   tcp_send_ack (tc);
 }
 
+/**
+ * Send Window Update ACK,
+ * ensuring that it will be sent once, if RWND became non-zero,
+ * after zero RWND has been advertised in ACK before
+ */
+void
+tcp_send_window_update_ack (tcp_connection_t * tc)
+{
+  tcp_worker_ctx_t *wrk = tcp_get_worker (tc->c_thread_index);
+  u32 win;
+
+  if (tcp_zero_rwnd_sent (tc))
+    {
+      win = tcp_window_to_advertise (tc, tc->state);
+      if (win > 0)
+	{
+	  tcp_zero_rwnd_sent_off (tc);
+	  tcp_program_ack (wrk, tc);
+	}
+    }
+}
+
 /**
  * Allocate a new buffer and build a new tcp segment
  *
@@ -1435,7 +1460,11 @@ tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk,
     return 0;
 
   if (tcp_in_fastrecovery (tc))
-    tc->snd_rxt_bytes += n_bytes;
+    {
+      tc->snd_rxt_bytes += n_bytes;
+      if (tc->flags & TCP_CONN_RATE_SAMPLE)
+	tcp_bt_track_rxt (tc, start, start + n_bytes);
+    }
 
 done:
   TCP_EVT_DBG (TCP_EVT_CC_RTX, tc, offset, n_bytes);
@@ -1446,26 +1475,22 @@ done:
  * Reset congestion control, switch cwnd to loss window and try again.
  */
 static void
-tcp_rxt_timeout_cc (tcp_connection_t * tc)
+tcp_cc_init_rxt_timeout (tcp_connection_t * tc)
 {
   TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 6);
   tc->prev_ssthresh = tc->ssthresh;
   tc->prev_cwnd = tc->cwnd;
 
-  /* Cleanly recover cc (also clears up fast retransmit) */
+  /* Clear fast recovery state if needed */
   if (tcp_in_fastrecovery (tc))
-    {
-      /* TODO be less aggressive about this */
-      scoreboard_clear (&tc->sack_sb);
-      tcp_cc_fastrecovery_exit (tc);
-    }
-  else
-    tc->rcv_dupacks = 0;
+    tcp_cc_fastrecovery_clear (tc);
+
+  /* Let cc algo decide loss cwnd and ssthresh */
+  tcp_cc_loss (tc);
 
   /* Start again from the beginning */
-  tc->cc_algo->congestion (tc);
-  tc->cwnd = tcp_loss_wnd (tc);
   tc->snd_congestion = tc->snd_nxt;
+  tc->rcv_dupacks = 0;
   tc->rtt_ts = 0;
   tc->cwnd_acc_bytes = 0;
   tcp_connection_tx_pacer_reset (tc, tc->cwnd, 2 * tc->snd_mss);
@@ -1534,15 +1559,32 @@ tcp_timer_retransmit_handler_i (u32 index, u8 is_syn)
 	  tcp_update_rto (tc);
 	}
 
+      /* Peer is dead or network connectivity is lost. Close connection.
+       * RFC 1122 section 4.2.3.5 recommends a value of at least 100s. For
+       * a min rto of 0.2s we need to retry about 8 times. */
+      if (tc->rto_boff >= TCP_RTO_BOFF_MAX)
+	{
+	  tcp_send_reset (tc);
+	  tcp_connection_set_state (tc, TCP_STATE_CLOSED);
+	  session_transport_closing_notify (&tc->connection);
+	  tcp_connection_timers_reset (tc);
+	  tcp_timer_update (tc, TCP_TIMER_WAITCLOSE, TCP_CLOSEWAIT_TIME);
+	  return;
+	}
+
       /* Increment RTO backoff (also equal to number of retries) and go back
        * to first un-acked byte  */
       tc->rto_boff += 1;
 
+      /* TODO be less aggressive about clearing scoreboard */
+      scoreboard_clear (&tc->sack_sb);
+
       /* First retransmit timeout */
       if (tc->rto_boff == 1)
-	tcp_rxt_timeout_cc (tc);
-      else
-	scoreboard_clear (&tc->sack_sb);
+	tcp_cc_init_rxt_timeout (tc);
+
+      if (tc->flags & TCP_CONN_RATE_SAMPLE)
+	tcp_bt_flush_samples (tc);
 
       /* If we've sent beyond snd_congestion, update it */
       tc->snd_congestion = seq_max (tc->snd_nxt, tc->snd_congestion);
@@ -1563,7 +1605,7 @@ tcp_timer_retransmit_handler_i (u32 index, u8 is_syn)
 
       /* For first retransmit, record timestamp (Eifel detection RFC3522) */
       if (tc->rto_boff == 1)
-	tc->snd_rxt_ts = tcp_time_now_w_thread (tc->c_thread_index);
+	tc->snd_rxt_ts = tcp_tstamp (tc);
 
       tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4);
       tcp_retransmit_timer_force_update (tc);
@@ -1908,12 +1950,13 @@ tcp_fast_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
   ASSERT (tcp_in_fastrecovery (tc));
   TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 0);
 
+  snd_space = tcp_available_cc_snd_space (tc);
+
   if (!tcp_fastrecovery_first (tc))
     goto send_unsent;
 
   /* RFC 6582: [If a partial ack], retransmit the first unacknowledged
    * segment. */
-  snd_space = tc->sack_sb.last_bytes_delivered;
   while (snd_space > 0 && n_segs < burst_size)
     {
       n_written = tcp_prepare_retransmit_segment (wrk, tc, offset,
@@ -1936,7 +1979,6 @@ tcp_fast_retransmit_no_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
 send_unsent:
 
   /* RFC 6582: Send a new segment if permitted by the new value of cwnd. */
-  snd_space = tcp_available_cc_snd_space (tc);
   if (snd_space < tc->snd_mss || tc->snd_mss == 0)
     goto done;
 
@@ -2066,6 +2108,13 @@ tcp_output_handle_packet (tcp_connection_t * tc0, vlib_buffer_t * b0,
       return;
     }
 
+  /* If next_index is not drop use it */
+  if (tc0->next_node_index)
+    {
+      *next0 = tc0->next_node_index;
+      vnet_buffer (b0)->tcp.next_node_opaque = tc0->next_node_opaque;
+    }
+
   vnet_buffer (b0)->sw_if_index[VLIB_TX] = tc0->c_fib_index;
   vnet_buffer (b0)->sw_if_index[VLIB_RX] = 0;