X-Git-Url: https://gerrit.fd.io/r/gitweb?a=blobdiff_plain;f=src%2Fvnet%2Ftcp%2Ftcp.h;h=3848f03f1dc862531ac1fcf8815489d959fabac1;hb=85a3ddd4c854c6217272d8be031cfcb04d2e7685;hp=37b10fd475326ad24e059b9a68a19c526bdec476;hpb=2c25a62cc1cc4937165de740a3b32d78429c72d6;p=vpp.git

diff --git a/src/vnet/tcp/tcp.h b/src/vnet/tcp/tcp.h
index 37b10fd4753..3848f03f1dc 100644
--- a/src/vnet/tcp/tcp.h
+++ b/src/vnet/tcp/tcp.h
@@ -30,9 +30,11 @@
 #define TCP_PAWS_IDLE 24 * 24 * 60 * 60 * THZ /**< 24 days */
 #define TCP_FIB_RECHECK_PERIOD	1 * THZ	/**< Recheck every 1s */
 #define TCP_MAX_OPTION_SPACE 40
+#define TCP_CC_DATA_SZ 24
 
 #define TCP_DUPACK_THRESHOLD 	3
-#define TCP_MAX_RX_FIFO_SIZE 	4 << 20
+#define TCP_MAX_RX_FIFO_SIZE 	32 << 20
+#define TCP_MIN_RX_FIFO_SIZE	4 << 10
 #define TCP_IW_N_SEGMENTS 	10
 #define TCP_ALWAYS_ACK		1	/**< On/off delayed acks */
 #define TCP_USE_SACKS		1	/**< Disable only for testing */
@@ -62,6 +64,7 @@ typedef enum _tcp_state
 format_function_t format_tcp_state;
 format_function_t format_tcp_flags;
 format_function_t format_tcp_sacks;
+format_function_t format_tcp_rcv_sacks;
 
 /** TCP timers */
 #define foreach_tcp_timer               \
@@ -71,7 +74,8 @@ format_function_t format_tcp_sacks;
   _(KEEP, "KEEP")                       \
   _(WAITCLOSE, "WAIT CLOSE")            \
   _(RETRANSMIT_SYN, "RETRANSMIT SYN")   \
-  _(ESTABLISH, "ESTABLISH")
+  _(ESTABLISH, "ESTABLISH")		\
+  _(ESTABLISH_AO, "ESTABLISH_AO")	\
 
 typedef enum _tcp_timers
 {
@@ -95,9 +99,12 @@ extern timer_expiration_handler tcp_timer_retransmit_syn_handler;
 						 * ticks to timer units */
 #define TCP_DELACK_TIME         1	/* 0.1s */
 #define TCP_ESTABLISH_TIME      750	/* 75s */
+#define TCP_SYN_RCVD_TIME	600	/* 60s */
 #define TCP_2MSL_TIME           300	/* 30s */
-#define TCP_CLOSEWAIT_TIME	20	/* 0.1s */
-#define TCP_CLEANUP_TIME	5	/* 0.5s Time to wait before cleanup */
+#define TCP_CLOSEWAIT_TIME	20	/* 2s */
+#define TCP_TIMEWAIT_TIME	100	/* 10s */
+#define TCP_FINWAIT1_TIME	600	/* 60s */
+#define TCP_CLEANUP_TIME	1	/* 0.1s */
 #define TCP_TIMER_PERSIST_MIN	2	/* 0.2s */
 
 #define TCP_RTO_MAX 60 * THZ	/* Min max RTO (60s) as per RFC6298 */
@@ -110,10 +117,16 @@ extern timer_expiration_handler tcp_timer_retransmit_syn_handler;
 #define foreach_tcp_connection_flag             \
   _(SNDACK, "Send ACK")                         \
   _(FINSNT, "FIN sent")				\
-  _(SENT_RCV_WND0, "Sent 0 receive window")     \
-  _(RECOVERY, "Recovery on")                    \
-  _(FAST_RECOVERY, "Fast Recovery on")		\
-  _(FR_1_SMSS, "Sent 1 SMSS")
+  _(SENT_RCV_WND0, "Sent 0 rcv_wnd")     	\
+  _(RECOVERY, "Recovery")                    	\
+  _(FAST_RECOVERY, "Fast Recovery")		\
+  _(DCNT_PENDING, "Disconnect pending")		\
+  _(HALF_OPEN_DONE, "Half-open completed")	\
+  _(FINPNDG, "FIN pending")			\
+  _(FRXT_PENDING, "Fast-retransmit pending")	\
+  _(FRXT_FIRST, "Fast-retransmit first again")	\
+  _(DEQ_PENDING, "Pending dequeue acked")	\
+  _(PSH_PENDING, "PSH pending")			\
 
 typedef enum _tcp_connection_flag_bits
 {
@@ -151,9 +164,19 @@ enum
 #undef _
 };
 
-#define TCP_MAX_SACK_BLOCKS 15	/**< Max number of SACK blocks stored */
+#define TCP_SCOREBOARD_TRACE (0)
+#define TCP_MAX_SACK_BLOCKS 256	/**< Max number of SACK blocks stored */
 #define TCP_INVALID_SACK_HOLE_INDEX ((u32)~0)
 
+typedef struct _scoreboard_trace_elt
+{
+  u32 start;
+  u32 end;
+  u32 ack;
+  u32 snd_una_max;
+  u32 group;
+} scoreboard_trace_elt_t;
+
 typedef struct _sack_scoreboard_hole
 {
   u32 next;		/**< Index for next entry in linked list */
@@ -177,11 +200,60 @@ typedef struct _sack_scoreboard
   u32 rescue_rxt;			/**< Rescue sequence number */
   u32 lost_bytes;			/**< Bytes lost as per RFC6675 */
   u32 cur_rxt_hole;			/**< Retransmitting from this hole */
+
+#if TCP_SCOREBOARD_TRACE
+  scoreboard_trace_elt_t *trace;
+#endif
+
 } sack_scoreboard_t;
 
+#if TCP_SCOREBOARD_TRACE
+#define tcp_scoreboard_trace_add(_tc, _ack) 				\
+{									\
+    static u64 _group = 0;						\
+    sack_scoreboard_t *_sb = &_tc->sack_sb;				\
+    sack_block_t *_sack, *_sacks;					\
+    scoreboard_trace_elt_t *_elt;					\
+    int i;								\
+    _group++;								\
+    _sacks = _tc->rcv_opts.sacks;					\
+    for (i = 0; i < vec_len (_sacks); i++) 				\
+      {									\
+	_sack = &_sacks[i];						\
+	vec_add2 (_sb->trace, _elt, 1);					\
+	_elt->start = _sack->start;					\
+	_elt->end = _sack->end;						\
+	_elt->ack = _elt->end == _ack ? _ack : 0;			\
+	_elt->snd_una_max = _elt->end == _ack ? _tc->snd_una_max : 0;	\
+	_elt->group = _group;						\
+      }									\
+}
+#else
+#define tcp_scoreboard_trace_add(_tc, _ack)
+#endif
+
+sack_scoreboard_hole_t *scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
+						  sack_scoreboard_hole_t *
+						  start, u8 have_sent_1_smss,
+						  u8 * can_rescue,
+						  u8 * snd_limited);
+sack_scoreboard_hole_t *scoreboard_get_hole (sack_scoreboard_t * sb,
+					     u32 index);
+
+sack_scoreboard_hole_t *scoreboard_next_hole (sack_scoreboard_t * sb,
+					      sack_scoreboard_hole_t * hole);
+sack_scoreboard_hole_t *scoreboard_prev_hole (sack_scoreboard_t * sb,
+					      sack_scoreboard_hole_t * hole);
+sack_scoreboard_hole_t *scoreboard_first_hole (sack_scoreboard_t * sb);
+sack_scoreboard_hole_t *scoreboard_last_hole (sack_scoreboard_t * sb);
+void scoreboard_clear (sack_scoreboard_t * sb);
+void scoreboard_init (sack_scoreboard_t * sb);
+u8 *format_tcp_scoreboard (u8 * s, va_list * args);
+
 typedef enum _tcp_cc_algorithm_type
 {
   TCP_CC_NEWRENO,
+  TCP_CC_CUBIC,
 } tcp_cc_algorithm_type_e;
 
 typedef struct _tcp_cc_algorithm tcp_cc_algorithm_t;
@@ -195,6 +267,7 @@ typedef enum _tcp_cc_ack_t
 
 typedef struct _tcp_connection
 {
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
   transport_connection_t connection;  /**< Common transport data. First! */
 
   u8 state;			/**< TCP state as per tcp_state_t */
@@ -221,53 +294,65 @@ typedef struct _tcp_connection
   u32 irs;		/**< initial remote sequence */
 
   /* Options */
-  tcp_options_t rcv_opts;	/**< Rx options for connection */
-  tcp_options_t snd_opts;	/**< Tx options for connection */
   u8 snd_opts_len;		/**< Tx options len */
-  u8 rcv_wscale;	/**< Window scale to advertise to peer */
-  u8 snd_wscale;	/**< Window scale to use when sending */
-  u32 tsval_recent;	/**< Last timestamp received */
-  u32 tsval_recent_age;	/**< When last updated tstamp_recent*/
+  u8 rcv_wscale;		/**< Window scale to advertise to peer */
+  u8 snd_wscale;		/**< Window scale to use when sending */
+  u32 tsval_recent;		/**< Last timestamp received */
+  u32 tsval_recent_age;		/**< When last updated tstamp_recent*/
+  tcp_options_t snd_opts;	/**< Tx options for connection */
+  tcp_options_t rcv_opts;	/**< Rx options for connection */
 
   sack_block_t *snd_sacks;	/**< Vector of SACKs to send. XXX Fixed size? */
   sack_scoreboard_t sack_sb;	/**< SACK "scoreboard" that tracks holes */
 
   u16 rcv_dupacks;	/**< Number of DUPACKs received */
-  u8 snt_dupacks;	/**< Number of DUPACKs sent in a burst */
+  u8 pending_dupacks;	/**< Number of DUPACKs to be sent */
 
   /* Congestion control */
   u32 cwnd;		/**< Congestion window */
+  u32 cwnd_acc_bytes;	/**< Bytes accumulated for cwnd increment */
   u32 ssthresh;		/**< Slow-start threshold */
   u32 prev_ssthresh;	/**< ssthresh before congestion */
   u32 prev_cwnd;	/**< ssthresh before congestion */
   u32 bytes_acked;	/**< Bytes acknowledged by current segment */
+  u32 burst_acked;	/**< Bytes acknowledged in current burst */
   u32 snd_rxt_bytes;	/**< Retransmitted bytes */
   u32 snd_rxt_ts;	/**< Timestamp when first packet is retransmitted */
   u32 tsecr_last_ack;	/**< Timestamp echoed to us in last healthy ACK */
   u32 snd_congestion;	/**< snd_una_max when congestion is detected */
   tcp_cc_algorithm_t *cc_algo;	/**< Congestion control algorithm */
+  u8 cc_data[TCP_CC_DATA_SZ];	/**< Congestion control algo private data */
 
   /* RTT and RTO */
   u32 rto;		/**< Retransmission timeout */
   u32 rto_boff;		/**< Index for RTO backoff */
   u32 srtt;		/**< Smoothed RTT */
   u32 rttvar;		/**< Smoothed mean RTT difference. Approximates variance */
-  u32 rtt_ts;		/**< Timestamp for tracked ACK */
   u32 rtt_seq;		/**< Sequence number for tracked ACK */
+  f64 rtt_ts;		/**< Timestamp for tracked ACK */
+  f64 mrtt_us;		/**< High precision mrtt from tracked acks */
 
   u16 mss;		/**< Our max seg size that includes options */
   u32 limited_transmit;	/**< snd_nxt when limited transmit starts */
   u32 last_fib_check;	/**< Last time we checked fib route for peer */
+  u32 sw_if_index;	/**< Interface for the connection */
+  u32 tx_fifo_size;	/**< Tx fifo size. Used to constrain cwnd */
+
+  u32 psh_seq;		/**< Add psh header for seg that includes this */
 } tcp_connection_t;
 
+/* *INDENT-OFF* */
 struct _tcp_cc_algorithm
 {
+  const char *name;
+  uword (*unformat_cfg) (unformat_input_t * input);
   void (*rcv_ack) (tcp_connection_t * tc);
   void (*rcv_cong_ack) (tcp_connection_t * tc, tcp_cc_ack_t ack);
   void (*congestion) (tcp_connection_t * tc);
   void (*recovered) (tcp_connection_t * tc);
   void (*init) (tcp_connection_t * tc);
 };
+/* *INDENT-ON* */
 
 #define tcp_fastrecovery_on(tc) (tc)->flags |= TCP_CONN_FAST_RECOVERY
 #define tcp_fastrecovery_off(tc) (tc)->flags &= ~TCP_CONN_FAST_RECOVERY
@@ -276,9 +361,12 @@ struct _tcp_cc_algorithm
 #define tcp_in_fastrecovery(tc) ((tc)->flags & TCP_CONN_FAST_RECOVERY)
 #define tcp_in_recovery(tc) ((tc)->flags & (TCP_CONN_RECOVERY))
 #define tcp_in_slowstart(tc) (tc->cwnd < tc->ssthresh)
-#define tcp_fastrecovery_sent_1_smss(tc) ((tc)->flags & TCP_CONN_FR_1_SMSS)
-#define tcp_fastrecovery_1_smss_on(tc) ((tc)->flags |= TCP_CONN_FR_1_SMSS)
-#define tcp_fastrecovery_1_smss_off(tc) ((tc)->flags &= ~TCP_CONN_FR_1_SMSS)
+#define tcp_disconnect_pending(tc) ((tc)->flags & TCP_CONN_DCNT_PENDING)
+#define tcp_disconnect_pending_on(tc) ((tc)->flags |= TCP_CONN_DCNT_PENDING)
+#define tcp_disconnect_pending_off(tc) ((tc)->flags &= ~TCP_CONN_DCNT_PENDING)
+#define tcp_fastrecovery_first(tc) ((tc)->flags & TCP_CONN_FRXT_FIRST)
+#define tcp_fastrecovery_first_on(tc) ((tc)->flags |= TCP_CONN_FRXT_FIRST)
+#define tcp_fastrecovery_first_off(tc) ((tc)->flags &= ~TCP_CONN_FRXT_FIRST)
 
 #define tcp_in_cong_recovery(tc) ((tc)->flags & 		\
 	  (TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY))
@@ -287,16 +375,9 @@ always_inline void
 tcp_cong_recovery_off (tcp_connection_t * tc)
 {
   tc->flags &= ~(TCP_CONN_FAST_RECOVERY | TCP_CONN_RECOVERY);
-  tcp_fastrecovery_1_smss_off (tc);
+  tcp_fastrecovery_first_off (tc);
 }
 
-typedef enum
-{
-  TCP_IP4,
-  TCP_IP6,
-  TCP_N_AF,
-} tcp_af_t;
-
 typedef enum _tcp_error
 {
 #define tcp_error(n,s) TCP_ERROR_##n,
@@ -310,6 +391,52 @@ typedef struct _tcp_lookup_dispatch
   u8 next, error;
 } tcp_lookup_dispatch_t;
 
+typedef struct tcp_worker_ctx_
+{
+  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
+  /** worker time */
+  u32 time_now;
+
+  /** worker timer wheel */
+  tw_timer_wheel_16t_2w_512sl_t timer_wheel;
+
+  /** tx buffer free list */
+  u32 *tx_buffers;
+
+  /** tx frames for tcp 4/6 output nodes */
+  vlib_frame_t *tx_frames[2];
+
+  /** tx frames for ip 4/6 lookup nodes */
+  vlib_frame_t *ip_lookup_tx_frames[2];
+
+  /** vector of connections needing fast rxt */
+  u32 *pending_fast_rxt;
+
+  /** vector of connections now doing fast rxt */
+  u32 *ongoing_fast_rxt;
+
+  /** vector of connections that will do fast rxt */
+  u32 *postponed_fast_rxt;
+
+  /** vector of pending ack dequeues */
+  u32 *pending_deq_acked;
+
+  /** vector of pending acks */
+  u32 *pending_acks;
+
+  /** vector of pending disconnect notifications */
+  u32 *pending_disconnects;
+
+  /** convenience pointer to this thread's vlib main */
+  vlib_main_t *vm;
+
+    CLIB_CACHE_LINE_ALIGN_MARK (cacheline1);
+
+  /** cached 'on the wire' options for bursts */
+  u8 cached_opts[40];
+
+} tcp_worker_ctx_t;
+
 typedef struct _tcp_main
 {
   /* Per-worker thread tcp connection pools */
@@ -324,30 +451,30 @@ typedef struct _tcp_main
   u8 log2_tstamp_clocks_per_tick;
   f64 tstamp_ticks_per_clock;
 
-  /** per-worker tx buffer free lists */
-  u32 **tx_buffers;
-
-  /* Per worker-thread timer wheel for connections timers */
-  tw_timer_wheel_16t_2w_512sl_t *timer_wheels;
-
-//  /* Convenience per worker-thread vector of connections to DELACK */
-//  u32 **delack_connections;
+  /** per-worker context */
+  tcp_worker_ctx_t *wrk_ctx;
 
   /* Pool of half-open connections on which we've sent a SYN */
   tcp_connection_t *half_open_connections;
-
-  /* Pool of local TCP endpoints */
-  transport_endpoint_t *local_endpoints;
-
-  /* Local endpoints lookup table */
-  transport_endpoint_table_t local_endpoints_table;
+  clib_spinlock_t half_open_lock;
 
   /* Congestion control algorithms registered */
   tcp_cc_algorithm_t *cc_algos;
 
+  /** vlib buffer size */
+  u32 bytes_per_buffer;
+
+  /*
+   * Configuration
+   */
+
   /* Flag that indicates if stack is on or off */
   u8 is_enabled;
 
+  /** Max rx fifo size for a session. It is used in to compute the
+   *  rfc 7323 window scaling factor */
+  u32 max_rx_fifo;
+
   /** Number of preallocated connections */
   u32 preallocated_connections;
   u32 preallocated_half_open_connections;
@@ -358,11 +485,18 @@ typedef struct _tcp_main
   u32 last_v6_address_rotor;
   ip6_address_t *ip6_src_addresses;
 
-  /* convenience */
-  vlib_main_t *vlib_main;
-  vnet_main_t *vnet_main;
-  ip4_main_t *ip4_main;
-  ip6_main_t *ip6_main;
+  /** Enable tx pacing for new connections */
+  u8 tx_pacing;
+
+  u8 punt_unknown4;
+  u8 punt_unknown6;
+
+  /** fault-injection */
+  f64 buffer_fail_fraction;
+
+  /** Default congestion control algorithm type */
+  tcp_cc_algorithm_type_e cc_algo;
+
 } tcp_main_t;
 
 extern tcp_main_t tcp_main;
@@ -377,6 +511,12 @@ vnet_get_tcp_main ()
   return &tcp_main;
 }
 
+always_inline tcp_worker_ctx_t *
+tcp_get_worker (u32 thread_index)
+{
+  return &tcp_main.wrk_ctx[thread_index];
+}
+
 always_inline tcp_header_t *
 tcp_buffer_hdr (vlib_buffer_t * b)
 {
@@ -385,12 +525,24 @@ tcp_buffer_hdr (vlib_buffer_t * b)
 			   + vnet_buffer (b)->tcp.hdr_offset);
 }
 
+#if (VLIB_BUFFER_TRACE_TRAJECTORY)
+#define tcp_trajectory_add_start(b, start)			\
+{								\
+    (*vlib_buffer_trace_trajectory_cb) (b, start);		\
+}
+#else
+#define tcp_trajectory_add_start(b, start)
+#endif
+
 clib_error_t *vnet_tcp_enable_disable (vlib_main_t * vm, u8 is_en);
 
+void tcp_punt_unknown (vlib_main_t * vm, u8 is_ip4, u8 is_add);
+
 always_inline tcp_connection_t *
 tcp_connection_get (u32 conn_index, u32 thread_index)
 {
-  if (pool_is_free_index (tcp_main.connections[thread_index], conn_index))
+  if (PREDICT_FALSE
+      (pool_is_free_index (tcp_main.connections[thread_index], conn_index)))
     return 0;
   return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
 }
@@ -405,14 +557,34 @@ tcp_connection_get_if_valid (u32 conn_index, u32 thread_index)
   return pool_elt_at_index (tcp_main.connections[thread_index], conn_index);
 }
 
+always_inline tcp_connection_t *
+tcp_get_connection_from_transport (transport_connection_t * tconn)
+{
+  return (tcp_connection_t *) tconn;
+}
+
+always_inline void
+tcp_connection_set_state (tcp_connection_t * tc, tcp_state_t state)
+{
+  tc->state = state;
+  TCP_EVT_DBG (TCP_EVT_STATE_CHANGE, tc);
+}
+
 void tcp_connection_close (tcp_connection_t * tc);
 void tcp_connection_cleanup (tcp_connection_t * tc);
 void tcp_connection_del (tcp_connection_t * tc);
+int tcp_half_open_connection_cleanup (tcp_connection_t * tc);
+tcp_connection_t *tcp_connection_alloc (u8 thread_index);
+void tcp_connection_free (tcp_connection_t * tc);
 void tcp_connection_reset (tcp_connection_t * tc);
-
-u8 *format_tcp_connection_id (u8 * s, va_list * args);
+int tcp_configure_v4_source_address_range (vlib_main_t * vm,
+					   ip4_address_t * start,
+					   ip4_address_t * end, u32 table_id);
+int tcp_configure_v6_source_address_range (vlib_main_t * vm,
+					   ip6_address_t * start,
+					   ip6_address_t * end, u32 table_id);
+void tcp_api_reference (void);
 u8 *format_tcp_connection (u8 * s, va_list * args);
-u8 *format_tcp_scoreboard (u8 * s, va_list * args);
 
 always_inline tcp_connection_t *
 tcp_listener_get (u32 tli)
@@ -423,18 +595,35 @@ tcp_listener_get (u32 tli)
 always_inline tcp_connection_t *
 tcp_half_open_connection_get (u32 conn_index)
 {
-  return pool_elt_at_index (tcp_main.half_open_connections, conn_index);
+  tcp_connection_t *tc = 0;
+  clib_spinlock_lock_if_init (&tcp_main.half_open_lock);
+  if (!pool_is_free_index (tcp_main.half_open_connections, conn_index))
+    tc = pool_elt_at_index (tcp_main.half_open_connections, conn_index);
+  clib_spinlock_unlock_if_init (&tcp_main.half_open_lock);
+  return tc;
 }
 
 void tcp_make_ack (tcp_connection_t * ts, vlib_buffer_t * b);
 void tcp_make_fin (tcp_connection_t * tc, vlib_buffer_t * b);
 void tcp_make_synack (tcp_connection_t * ts, vlib_buffer_t * b);
-void tcp_send_reset (vlib_buffer_t * pkt, u8 is_ip4);
+void tcp_send_reset_w_pkt (tcp_connection_t * tc, vlib_buffer_t * pkt,
+			   u8 is_ip4);
+void tcp_send_reset (tcp_connection_t * tc);
 void tcp_send_syn (tcp_connection_t * tc);
+void tcp_send_synack (tcp_connection_t * tc);
 void tcp_send_fin (tcp_connection_t * tc);
 void tcp_init_mss (tcp_connection_t * tc);
-void tcp_update_snd_mss (tcp_connection_t * tc);
+void tcp_update_burst_snd_vars (tcp_connection_t * tc);
 void tcp_update_rto (tcp_connection_t * tc);
+void tcp_flush_frame_to_output (tcp_worker_ctx_t * wrk, u8 is_ip4);
+void tcp_flush_frames_to_output (tcp_worker_ctx_t * wrk);
+void tcp_program_fastretransmit (tcp_worker_ctx_t * wrk,
+				 tcp_connection_t * tc);
+void tcp_do_fastretransmits (tcp_worker_ctx_t * wrk);
+
+void tcp_program_ack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc);
+void tcp_program_dupack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc);
+void tcp_send_acks (tcp_worker_ctx_t * wrk);
 
 always_inline u32
 tcp_end_seq (tcp_header_t * th, u32 len)
@@ -504,6 +693,25 @@ tcp_initial_cwnd (const tcp_connection_t * tc)
     return 4 * tc->snd_mss;
 }
 
+/*
+ * Accumulate acked bytes for cwnd increase
+ *
+ * Once threshold bytes are accumulated, snd_mss bytes are added
+ * to the cwnd.
+ */
+always_inline void
+tcp_cwnd_accumulate (tcp_connection_t * tc, u32 thresh, u32 bytes)
+{
+  tc->cwnd_acc_bytes += bytes;
+  if (tc->cwnd_acc_bytes >= thresh)
+    {
+      u32 inc = tc->cwnd_acc_bytes / thresh;
+      tc->cwnd_acc_bytes -= inc * thresh;
+      tc->cwnd += inc * tc->snd_mss;
+      tc->cwnd = clib_min (tc->cwnd, tc->tx_fifo_size);
+    }
+}
+
 always_inline u32
 tcp_loss_wnd (const tcp_connection_t * tc)
 {
@@ -511,15 +719,30 @@ tcp_loss_wnd (const tcp_connection_t * tc)
 }
 
 always_inline u32
-tcp_available_wnd (const tcp_connection_t * tc)
+tcp_available_snd_wnd (const tcp_connection_t * tc)
 {
   return clib_min (tc->cwnd, tc->snd_wnd);
 }
 
 always_inline u32
-tcp_available_snd_space (const tcp_connection_t * tc)
+tcp_available_output_snd_space (const tcp_connection_t * tc)
 {
-  u32 available_wnd = tcp_available_wnd (tc);
+  u32 available_wnd = tcp_available_snd_wnd (tc);
+  int flight_size = (int) (tc->snd_nxt - tc->snd_una);
+
+  if (available_wnd <= flight_size)
+    return 0;
+
+  return available_wnd - flight_size;
+}
+
+/**
+ * Estimate of how many bytes we can still push into the network
+ */
+always_inline u32
+tcp_available_cc_snd_space (const tcp_connection_t * tc)
+{
+  u32 available_wnd = tcp_available_snd_wnd (tc);
   u32 flight_size = tcp_flight_size (tc);
 
   if (available_wnd <= flight_size)
@@ -528,61 +751,83 @@ tcp_available_snd_space (const tcp_connection_t * tc)
   return available_wnd - flight_size;
 }
 
-i32 tcp_rcv_wnd_available (tcp_connection_t * tc);
-u32 tcp_snd_space (tcp_connection_t * tc);
-void tcp_update_rcv_wnd (tcp_connection_t * tc);
+always_inline u8
+tcp_is_lost_fin (tcp_connection_t * tc)
+{
+  if ((tc->flags & TCP_CONN_FINSNT) && tc->snd_una_max - tc->snd_una == 1)
+    return 1;
+  return 0;
+}
 
-void tcp_retransmit_first_unacked (tcp_connection_t * tc);
-void tcp_fast_retransmit_no_sack (tcp_connection_t * tc);
-void tcp_fast_retransmit_sack (tcp_connection_t * tc);
-void tcp_fast_retransmit (tcp_connection_t * tc);
+u32 tcp_snd_space (tcp_connection_t * tc);
+int tcp_retransmit_first_unacked (tcp_worker_ctx_t * wrk,
+				  tcp_connection_t * tc);
+int tcp_fast_retransmit_no_sack (tcp_worker_ctx_t * wrk,
+				 tcp_connection_t * tc, u32 burst_size);
+int tcp_fast_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
+			      u32 burst_size);
+int tcp_fast_retransmit (tcp_worker_ctx_t * wrk, tcp_connection_t * tc,
+			 u32 burst_size);
 void tcp_cc_init_congestion (tcp_connection_t * tc);
-int tcp_cc_recover (tcp_connection_t * tc);
 void tcp_cc_fastrecovery_exit (tcp_connection_t * tc);
 
 fib_node_index_t tcp_lookup_rmt_in_fib (tcp_connection_t * tc);
 
 /* Made public for unit testing only */
 void tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end);
+u32 tcp_sack_list_bytes (tcp_connection_t * tc);
 
 always_inline u32
 tcp_time_now (void)
 {
-  return clib_cpu_time_now () * tcp_main.tstamp_ticks_per_clock;
+  return tcp_main.wrk_ctx[vlib_get_thread_index ()].time_now;
 }
 
-always_inline void
-tcp_update_time (f64 now, u32 thread_index)
+always_inline u32
+tcp_time_now_w_thread (u32 thread_index)
+{
+  return tcp_main.wrk_ctx[thread_index].time_now;
+}
+
+always_inline f64
+tcp_time_now_us (u32 thread_index)
 {
-  tw_timer_expire_timers_16t_2w_512sl (&tcp_main.timer_wheels[thread_index],
-				       now);
+  return transport_time_now (thread_index);
 }
 
-u32 tcp_push_header (transport_connection_t * tconn, vlib_buffer_t * b);
+always_inline u32
+tcp_set_time_now (tcp_worker_ctx_t * wrk)
+{
+  wrk->time_now = clib_cpu_time_now () * tcp_main.tstamp_ticks_per_clock;
+  return wrk->time_now;
+}
 
-u32
-tcp_prepare_retransmit_segment (tcp_connection_t * tc, vlib_buffer_t * b,
-				u32 offset, u32 max_bytes);
+u32 tcp_push_header (tcp_connection_t * tconn, vlib_buffer_t * b);
 
 void tcp_connection_timers_init (tcp_connection_t * tc);
 void tcp_connection_timers_reset (tcp_connection_t * tc);
+void tcp_init_snd_vars (tcp_connection_t * tc);
 void tcp_connection_init_vars (tcp_connection_t * tc);
+void tcp_connection_tx_pacer_update (tcp_connection_t * tc);
+void tcp_connection_tx_pacer_reset (tcp_connection_t * tc, u32 window,
+				    u32 start_bucket);
 
 always_inline void
-tcp_connection_force_ack (tcp_connection_t * tc, vlib_buffer_t * b)
+tcp_cc_rcv_ack (tcp_connection_t * tc)
 {
-  /* Reset flags, make sure ack is sent */
-  tc->flags = TCP_CONN_SNDACK;
-  vnet_buffer (b)->tcp.flags &= ~TCP_BUF_FLAG_DUPACK;
+  tc->cc_algo->rcv_ack (tc);
+  tc->tsecr_last_ack = tc->rcv_opts.tsecr;
 }
 
 always_inline void
 tcp_timer_set (tcp_connection_t * tc, u8 timer_id, u32 interval)
 {
   ASSERT (tc->c_thread_index == vlib_get_thread_index ());
-  tc->timers[timer_id]
-    = tw_timer_start_16t_2w_512sl (&tcp_main.timer_wheels[tc->c_thread_index],
-				   tc->c_c_index, timer_id, interval);
+  ASSERT (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID);
+  tc->timers[timer_id] =
+    tw_timer_start_16t_2w_512sl (&tcp_main.
+				 wrk_ctx[tc->c_thread_index].timer_wheel,
+				 tc->c_c_index, timer_id, interval);
 }
 
 always_inline void
@@ -592,7 +837,8 @@ tcp_timer_reset (tcp_connection_t * tc, u8 timer_id)
   if (tc->timers[timer_id] == TCP_TIMER_HANDLE_INVALID)
     return;
 
-  tw_timer_stop_16t_2w_512sl (&tcp_main.timer_wheels[tc->c_thread_index],
+  tw_timer_stop_16t_2w_512sl (&tcp_main.
+			      wrk_ctx[tc->c_thread_index].timer_wheel,
 			      tc->timers[timer_id]);
   tc->timers[timer_id] = TCP_TIMER_HANDLE_INVALID;
 }
@@ -602,17 +848,20 @@ tcp_timer_update (tcp_connection_t * tc, u8 timer_id, u32 interval)
 {
   ASSERT (tc->c_thread_index == vlib_get_thread_index ());
   if (tc->timers[timer_id] != TCP_TIMER_HANDLE_INVALID)
-    tw_timer_stop_16t_2w_512sl (&tcp_main.timer_wheels[tc->c_thread_index],
-				tc->timers[timer_id]);
-  tc->timers[timer_id] =
-    tw_timer_start_16t_2w_512sl (&tcp_main.timer_wheels[tc->c_thread_index],
-				 tc->c_c_index, timer_id, interval);
+    tw_timer_update_16t_2w_512sl (&tcp_main.
+				  wrk_ctx[tc->c_thread_index].timer_wheel,
+				  tc->timers[timer_id], interval);
+  else
+    tc->timers[timer_id] =
+      tw_timer_start_16t_2w_512sl (&tcp_main.
+				   wrk_ctx[tc->c_thread_index].timer_wheel,
+				   tc->c_c_index, timer_id, interval);
 }
 
-/* XXX Switch retransmit to faster TW */
 always_inline void
 tcp_retransmit_timer_set (tcp_connection_t * tc)
 {
+  ASSERT (tc->snd_una != tc->snd_una_max);
   tcp_timer_set (tc, TCP_TIMER_RETRANSMIT,
 		 clib_max (tc->rto * TCP_TO_TIMER_TICK, 1));
 }
@@ -660,7 +909,7 @@ tcp_retransmit_timer_update (tcp_connection_t * tc)
     {
       tcp_retransmit_timer_reset (tc);
       if (tc->snd_wnd < tc->snd_mss)
-	tcp_persist_timer_set (tc);
+	tcp_persist_timer_update (tc);
     }
   else
     tcp_timer_update (tc, TCP_TIMER_RETRANSMIT,
@@ -675,121 +924,23 @@ tcp_timer_is_active (tcp_connection_t * tc, tcp_timers_e timer)
 
 #define tcp_validate_txf_size(_tc, _a) 					\
   ASSERT(_tc->state != TCP_STATE_ESTABLISHED 				\
-	 || stream_session_tx_fifo_max_dequeue (&_tc->connection) >= _a)
-
-void
-scoreboard_remove_hole (sack_scoreboard_t * sb,
-			sack_scoreboard_hole_t * hole);
-void scoreboard_update_lost (tcp_connection_t * tc, sack_scoreboard_t * sb);
-sack_scoreboard_hole_t *scoreboard_insert_hole (sack_scoreboard_t * sb,
-						u32 prev_index, u32 start,
-						u32 end);
-sack_scoreboard_hole_t *scoreboard_next_rxt_hole (sack_scoreboard_t * sb,
-						  sack_scoreboard_hole_t *
-						  start, u8 have_sent_1_smss,
-						  u8 * can_rescue,
-						  u8 * snd_limited);
-void scoreboard_init_high_rxt (sack_scoreboard_t * sb);
-
-always_inline sack_scoreboard_hole_t *
-scoreboard_get_hole (sack_scoreboard_t * sb, u32 index)
-{
-  if (index != TCP_INVALID_SACK_HOLE_INDEX)
-    return pool_elt_at_index (sb->holes, index);
-  return 0;
-}
-
-always_inline sack_scoreboard_hole_t *
-scoreboard_next_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
-{
-  if (hole->next != TCP_INVALID_SACK_HOLE_INDEX)
-    return pool_elt_at_index (sb->holes, hole->next);
-  return 0;
-}
-
-always_inline sack_scoreboard_hole_t *
-scoreboard_prev_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
-{
-  if (hole->prev != TCP_INVALID_SACK_HOLE_INDEX)
-    return pool_elt_at_index (sb->holes, hole->prev);
-  return 0;
-}
-
-always_inline sack_scoreboard_hole_t *
-scoreboard_first_hole (sack_scoreboard_t * sb)
-{
-  if (sb->head != TCP_INVALID_SACK_HOLE_INDEX)
-    return pool_elt_at_index (sb->holes, sb->head);
-  return 0;
-}
-
-always_inline sack_scoreboard_hole_t *
-scoreboard_last_hole (sack_scoreboard_t * sb)
-{
-  if (sb->tail != TCP_INVALID_SACK_HOLE_INDEX)
-    return pool_elt_at_index (sb->holes, sb->tail);
-  return 0;
-}
-
-always_inline void
-scoreboard_clear (sack_scoreboard_t * sb)
-{
-  sack_scoreboard_hole_t *hole;
-  while ((hole = scoreboard_first_hole (sb)))
-    {
-      scoreboard_remove_hole (sb, hole);
-    }
-  ASSERT (sb->head == sb->tail && sb->head == TCP_INVALID_SACK_HOLE_INDEX);
-  sb->sacked_bytes = 0;
-  sb->last_sacked_bytes = 0;
-  sb->last_bytes_delivered = 0;
-  sb->snd_una_adv = 0;
-  sb->high_sacked = 0;
-  sb->high_rxt = 0;
-  sb->lost_bytes = 0;
-  sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
-}
-
-always_inline u32
-scoreboard_hole_bytes (sack_scoreboard_hole_t * hole)
-{
-  return hole->end - hole->start;
-}
-
-always_inline u32
-scoreboard_hole_index (sack_scoreboard_t * sb, sack_scoreboard_hole_t * hole)
-{
-  return hole - sb->holes;
-}
-
-always_inline void
-scoreboard_init (sack_scoreboard_t * sb)
-{
-  sb->head = TCP_INVALID_SACK_HOLE_INDEX;
-  sb->tail = TCP_INVALID_SACK_HOLE_INDEX;
-  sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX;
-}
+	 || session_tx_fifo_max_dequeue (&_tc->connection) >= _a)
 
 void tcp_rcv_sacks (tcp_connection_t * tc, u32 ack);
+u8 *tcp_scoreboard_replay (u8 * s, tcp_connection_t * tc, u8 verbose);
 
-always_inline void
-tcp_cc_algo_register (tcp_cc_algorithm_type_e type,
-		      const tcp_cc_algorithm_t * vft)
-{
-  tcp_main_t *tm = vnet_get_tcp_main ();
-  vec_validate (tm->cc_algos, type);
+void tcp_cc_algo_register (tcp_cc_algorithm_type_e type,
+			   const tcp_cc_algorithm_t * vft);
 
-  tm->cc_algos[type] = *vft;
-}
+tcp_cc_algorithm_t *tcp_cc_algo_get (tcp_cc_algorithm_type_e type);
 
-always_inline tcp_cc_algorithm_t *
-tcp_cc_algo_get (tcp_cc_algorithm_type_e type)
+static inline void *
+tcp_cc_data (tcp_connection_t * tc)
 {
-  tcp_main_t *tm = vnet_get_tcp_main ();
-  return &tm->cc_algos[type];
+  return (void *) tc->cc_data;
 }
 
-void tcp_cc_init (tcp_connection_t * tc);
+void newreno_rcv_cong_ack (tcp_connection_t * tc, tcp_cc_ack_t ack_type);
 
 /**
  * Push TCP header to buffer