1 /*- 2 * Copyright (c) 2016 Netflix, Inc. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 14 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 17 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23 * SUCH DAMAGE. 24 * 25 * $FreeBSD$ 26 */ 27 28 #ifndef _NETINET_TCP_RACK_H_ 29 #define _NETINET_TCP_RACK_H_ 30 31 #define RACK_ACKED 0x0001/* The remote endpoint acked this */ 32 #define RACK_TO_MIXED 0x0002/* A timeout occured that mixed the send order */ 33 #define RACK_DEFERRED 0x0004/* We can't use this for RTT calc */ 34 #define RACK_OVERMAX 0x0008/* We have more retran's then we can fit */ 35 #define RACK_SACK_PASSED 0x0010/* A sack was done above this block */ 36 #define RACK_WAS_SACKPASS 0x0020/* We retransmitted due to SACK pass */ 37 #define RACK_HAS_FIN 0x0040/* segment is sent with fin */ 38 #define RACK_TLP 0x0080/* segment sent as tail-loss-probe */ 39 40 #define RACK_NUM_OF_RETRANS 3 41 42 #define RACK_INITIAL_RTO 1000 /* 1 second in milli seconds */ 43 44 struct rack_sendmap { 45 TAILQ_ENTRY(rack_sendmap) r_next; /* seq number arrayed next */ 46 TAILQ_ENTRY(rack_sendmap) r_tnext; /* Time of transmit based next */ 47 uint32_t r_tim_lastsent[RACK_NUM_OF_RETRANS]; 48 uint32_t r_start; /* Sequence number of the segment */ 49 uint32_t r_end; /* End seq, this is 1 beyond actually */ 50 uint32_t r_rtr_bytes; /* How many bytes have been retransmitted */ 51 uint16_t r_rtr_cnt; /* Retran count, index this -1 to get time 52 * sent */ 53 uint8_t r_flags; /* Flags as defined above */ 54 uint8_t r_sndcnt; /* Retran count, not limited by 55 * RACK_NUM_OF_RETRANS */ 56 uint8_t r_in_tmap; /* Flag to see if its in the r_tnext array */ 57 uint8_t r_resv[3]; 58 }; 59 60 TAILQ_HEAD(rack_head, rack_sendmap); 61 62 63 /* 64 * We use the rate sample structure to 65 * assist in single sack/ack rate and rtt 66 * calculation. In the future we will expand 67 * this in BBR to do forward rate sample 68 * b/w estimation. 69 */ 70 #define RACK_RTT_EMPTY 0x00000001 /* Nothing yet stored in RTT's */ 71 #define RACK_RTT_VALID 0x00000002 /* We have at least one valid RTT */ 72 struct rack_rtt_sample { 73 uint32_t rs_flags; 74 uint32_t rs_rtt_lowest; 75 uint32_t rs_rtt_highest; 76 uint32_t rs_rtt_cnt; 77 uint64_t rs_rtt_tot; 78 }; 79 80 #define RACK_LOG_TYPE_ACK 0x01 81 #define RACK_LOG_TYPE_OUT 0x02 82 #define RACK_LOG_TYPE_TO 0x03 83 #define RACK_LOG_TYPE_ALLOC 0x04 84 #define RACK_LOG_TYPE_FREE 0x05 85 86 87 struct rack_log { 88 union { 89 struct rack_sendmap *rsm; /* For alloc/free */ 90 uint64_t sb_acc;/* For out/ack or t-o */ 91 }; 92 uint32_t th_seq; 93 uint32_t th_ack; 94 uint32_t snd_una; 95 uint32_t snd_nxt; /* th_win for TYPE_ACK */ 96 uint32_t snd_max; 97 uint32_t blk_start[4]; 98 uint32_t blk_end[4]; 99 uint8_t type; 100 uint8_t n_sackblks; 101 uint16_t len; /* Timeout T3=1, TLP=2, RACK=3 */ 102 }; 103 104 /* 105 * Magic numbers for logging timeout events if the 106 * logging is enabled. 107 */ 108 #define RACK_TO_FRM_TMR 1 109 #define RACK_TO_FRM_TLP 2 110 #define RACK_TO_FRM_RACK 3 111 #define RACK_TO_FRM_KEEP 4 112 #define RACK_TO_FRM_PERSIST 5 113 #define RACK_TO_FRM_DELACK 6 114 115 struct rack_opts_stats { 116 uint64_t tcp_rack_prop_rate; 117 uint64_t tcp_rack_prop; 118 uint64_t tcp_rack_tlp_reduce; 119 uint64_t tcp_rack_early_recov; 120 uint64_t tcp_rack_pace_always; 121 uint64_t tcp_rack_pace_reduce; 122 uint64_t tcp_rack_max_seg; 123 uint64_t tcp_rack_prr_sendalot; 124 uint64_t tcp_rack_min_to; 125 uint64_t tcp_rack_early_seg; 126 uint64_t tcp_rack_reord_thresh; 127 uint64_t tcp_rack_reord_fade; 128 uint64_t tcp_rack_tlp_thresh; 129 uint64_t tcp_rack_pkt_delay; 130 uint64_t tcp_rack_tlp_inc_var; 131 uint64_t tcp_tlp_use; 132 uint64_t tcp_rack_idle_reduce; 133 uint64_t tcp_rack_idle_reduce_high; 134 uint64_t rack_no_timer_in_hpts; 135 uint64_t tcp_rack_min_pace_seg; 136 uint64_t tcp_rack_min_pace; 137 }; 138 139 #define TLP_USE_ID 1 /* Internet draft behavior */ 140 #define TLP_USE_TWO_ONE 2 /* Use 2.1 behavior */ 141 #define TLP_USE_TWO_TWO 3 /* Use 2.2 behavior */ 142 143 #ifdef _KERNEL 144 #define RACK_OPTS_SIZE (sizeof(struct rack_opts_stats)/sizeof(uint64_t)) 145 extern counter_u64_t rack_opts_arry[RACK_OPTS_SIZE]; 146 #define RACK_OPTS_ADD(name, amm) counter_u64_add(rack_opts_arry[(offsetof(struct rack_opts_stats, name)/sizeof(uint64_t))], (amm)) 147 #define RACK_OPTS_INC(name) RACK_OPTS_ADD(name, 1) 148 #endif 149 /* 150 * As we get each SACK we wade through the 151 * rc_map and mark off what is acked. 152 * We also increment rc_sacked as well. 153 * 154 * We also pay attention to missing entries 155 * based on the time and possibly mark them 156 * for retransmit. If we do and we are not already 157 * in recovery we enter recovery. In doing 158 * so we claer prr_delivered/holes_rxt and prr_sent_dur_rec. 159 * We also setup rc_next/rc_snd_nxt/rc_send_end so 160 * we will know where to send from. When not in 161 * recovery rc_next will be NULL and rc_snd_nxt should 162 * equal snd_max. 163 * 164 * Whenever we retransmit from recovery we increment 165 * rc_holes_rxt as we retran a block and mark it as retransmitted 166 * with the time it was sent. During non-recovery sending we 167 * add to our map and note the time down of any send expanding 168 * the rc_map at the tail and moving rc_snd_nxt up with snd_max. 169 * 170 * In recovery during SACK/ACK processing if a chunk has 171 * been retransmitted and it is now acked, we decrement rc_holes_rxt. 172 * When we retransmit from the scoreboard we use 173 * rc_next and rc_snd_nxt/rc_send_end to help us 174 * find what needs to be retran. 175 * 176 * To calculate pipe we simply take (snd_max - snd_una) + rc_holes_rxt 177 * This gets us the effect of RFC6675 pipe, counting twice for 178 * bytes retransmitted. 179 */ 180 181 #define TT_RACK_FR_TMR 0x2000 182 183 /* 184 * Locking for the rack control block. 185 * a) Locked by INP_WLOCK 186 * b) Locked by the hpts-mutex 187 * 188 */ 189 190 struct rack_control { 191 /* Second cache line 0x40 from tcp_rack */ 192 struct rack_head rc_map;/* List of all segments Lock(a) */ 193 struct rack_head rc_tmap; /* List in transmit order Lock(a) */ 194 struct rack_sendmap *rc_tlpsend; /* Remembered place for 195 * tlp_sending Lock(a) */ 196 struct rack_sendmap *rc_resend; /* something we have been asked to 197 * resend */ 198 uint32_t rc_hpts_flags; 199 uint32_t rc_timer_exp; /* If a timer ticks of expiry */ 200 uint32_t rc_rack_min_rtt; /* lowest RTT seen Lock(a) */ 201 uint32_t rc_rack_largest_cwnd; /* Largest CWND we have seen Lock(a) */ 202 203 /* Third Cache line 0x80 */ 204 struct rack_head rc_free; /* Allocation array */ 205 uint32_t rc_time_last_sent; /* Time we last sent some data and 206 * logged it Lock(a). */ 207 uint32_t rc_reorder_ts; /* Last time we saw reordering Lock(a) */ 208 209 uint32_t rc_tlp_new_data; /* we need to send new-data on a TLP 210 * Lock(a) */ 211 uint32_t rc_prr_out; /* bytes sent during recovery Lock(a) */ 212 213 uint32_t rc_prr_recovery_fs; /* recovery fs point Lock(a) */ 214 215 uint32_t rc_prr_sndcnt; /* Prr sndcnt Lock(a) */ 216 217 uint32_t rc_sacked; /* Tot sacked on scoreboard Lock(a) */ 218 uint32_t rc_last_tlp_seq; /* Last tlp sequence Lock(a) */ 219 220 uint32_t rc_prr_delivered; /* during recovery prr var Lock(a) */ 221 uint16_t rc_tlp_send_cnt; /* Number of TLP sends we have done 222 * since peer spoke to us Lock(a) */ 223 uint16_t rc_tlp_seg_send_cnt; /* Number of times we have TLP sent 224 * rc_last_tlp_seq Lock(a) */ 225 226 uint32_t rc_loss_count; /* During recovery how many segments were lost 227 * Lock(a) */ 228 uint32_t rc_reorder_fade; /* Socket option value Lock(a) */ 229 230 /* Forth cache line 0xc0 */ 231 /* Times */ 232 233 uint32_t rc_rack_tmit_time; /* Rack transmit time Lock(a) */ 234 uint32_t rc_holes_rxt; /* Tot retraned from scoreboard Lock(a) */ 235 236 /* Variables to track bad retransmits and recover */ 237 uint32_t rc_rsm_start; /* RSM seq number we retransmitted Lock(a) */ 238 uint32_t rc_cwnd_at; /* cwnd at the retransmit Lock(a) */ 239 240 uint32_t rc_ssthresh_at;/* ssthresh at the retransmit Lock(a) */ 241 uint32_t rc_num_maps_alloced; /* Number of map blocks (sacks) we 242 * have allocated */ 243 uint32_t rc_rcvtime; /* When we last received data */ 244 uint32_t rc_notused; 245 uint32_t rc_last_output_to; 246 uint32_t rc_went_idle_time; 247 248 struct rack_sendmap *rc_sacklast; /* sack remembered place 249 * Lock(a) */ 250 251 struct rack_sendmap *rc_next; /* remembered place where we next 252 * retransmit at Lock(a) */ 253 struct rack_sendmap *rc_rsm_at_retran; /* Debug variable kept for 254 * cache line alignment 255 * Lock(a) */ 256 /* Cache line split 0x100 */ 257 struct sack_filter rack_sf; 258 /* Cache line split 0x140 */ 259 /* Flags for various things */ 260 struct rack_rtt_sample rack_rs; 261 uint32_t rc_tlp_threshold; /* Socket option value Lock(a) */ 262 uint16_t rc_early_recovery_segs; /* Socket option value Lock(a) */ 263 uint16_t rc_reorder_shift; /* Socket option value Lock(a) */ 264 uint16_t rc_pkt_delay; /* Socket option value Lock(a) */ 265 uint8_t rc_prop_rate; /* Socket option value Lock(a) */ 266 uint8_t rc_prop_reduce; /* Socket option value Lock(a) */ 267 uint8_t rc_tlp_cwnd_reduce; /* Socket option value Lock(a) */ 268 uint8_t rc_early_recovery; /* Socket option value Lock(a) */ 269 uint8_t rc_prr_sendalot;/* Socket option value Lock(a) */ 270 uint8_t rc_min_to; /* Socket option value Lock(a) */ 271 uint8_t rc_prr_inc_var; /* Socket option value Lock(a) */ 272 uint8_t rc_tlp_rtx_out; /* This is TLPRtxOut in the draft */ 273 uint8_t rc_rate_sample_method; 274 }; 275 276 #ifdef _KERNEL 277 278 struct tcp_rack { 279 /* First cache line 0x00 */ 280 TAILQ_ENTRY(tcp_rack) r_hpts; /* hptsi queue next Lock(b) */ 281 int32_t(*r_substate) (struct mbuf *, struct tcphdr *, 282 struct socket *, struct tcpcb *, struct tcpopt *, 283 int32_t, int32_t, uint32_t, int, int); /* Lock(a) */ 284 struct tcpcb *rc_tp; /* The tcpcb Lock(a) */ 285 struct inpcb *rc_inp; /* The inpcb Lock(a) */ 286 uint32_t rc_free_cnt; /* Number of free entries on the rc_free list 287 * Lock(a) */ 288 uint32_t rc_rack_rtt; /* RACK-RTT Lock(a) */ 289 uint16_t r_wanted_output; /* Output routine wanted to be called */ 290 uint16_t r_cpu; /* CPU that the INP is running on Lock(a) */ 291 uint16_t rc_pace_max_segs; /* Socket option value Lock(a) */ 292 uint16_t rc_pace_reduce;/* Socket option value Lock(a) */ 293 294 uint8_t r_state; /* Current rack state Lock(a) */ 295 uint8_t rc_tmr_stopped : 7, 296 t_timers_stopped : 1; 297 uint8_t rc_enobuf; /* count of enobufs on connection provides 298 * backoff Lock(a) */ 299 uint8_t r_timer_override : 1, /* hpts override Lock(a) */ 300 r_tlp_running : 1, /* Running from a TLP timeout Lock(a) */ 301 r_is_v6 : 1, /* V6 pcb Lock(a) */ 302 rc_in_persist : 1, 303 rc_last_pto_set : 1, /* XXX not used */ 304 rc_tlp_in_progress : 1, 305 rc_always_pace : 1, /* Socket option value Lock(a) */ 306 rc_timer_up : 1; /* The rack timer is up flag Lock(a) */ 307 uint8_t r_idle_reduce_largest : 1, 308 r_enforce_min_pace : 2, 309 r_min_pace_seg_thresh : 5; 310 uint8_t rack_tlp_threshold_use; 311 uint8_t rc_allow_data_af_clo: 1, 312 delayed_ack : 1, 313 rc_avail : 6; 314 uint8_t r_resv[2]; /* Fill to cache line boundary */ 315 /* Cache line 2 0x40 */ 316 struct rack_control r_ctl; 317 } __aligned(CACHE_LINE_SIZE); 318 319 #endif 320 #endif 321