1 /*- 2 * Copyright (c) 2016-2020 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 - not used */ 33 #define RACK_DEFERRED 0x0004/* We can't use this for RTT calc - not used */ 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 #define RACK_RWND_COLLAPSED 0x0100/* The peer collapsed the rwnd on the segment */ 40 #define RACK_APP_LIMITED 0x0200/* We went app limited after this send */ 41 #define RACK_WAS_ACKED 0x0400/* a RTO undid the ack, but it already had a rtt calc done */ 42 #define RACK_HAS_SIN 0x0800/* SIN is on this guy */ 43 #define RACK_NUM_OF_RETRANS 3 44 45 #define RACK_INITIAL_RTO 1000 /* 1 second in milli seconds */ 46 47 #define RACK_REQ_AVG 4 /* Must be less than 256 */ 48 49 struct rack_sendmap { 50 uint32_t r_start; /* Sequence number of the segment */ 51 uint32_t r_end; /* End seq, this is 1 beyond actually */ 52 TAILQ_ENTRY(rack_sendmap) r_tnext; /* Time of transmit based next */ 53 RB_ENTRY(rack_sendmap) r_next; /* RB Tree next */ 54 uint32_t r_rtr_bytes; /* How many bytes have been retransmitted */ 55 uint16_t r_rtr_cnt; /* Retran count, index this -1 to get time 56 * sent */ 57 uint16_t r_flags; /* Flags as defined above */ 58 uint32_t r_tim_lastsent[RACK_NUM_OF_RETRANS]; 59 uint32_t usec_orig_send; /* time of orginal send in useconds */ 60 uint32_t r_nseq_appl; /* If this one is app limited, this is the nxt seq limited */ 61 uint32_t r_ack_arrival; /* This is the time of ack-arrival (if SACK'd) */ 62 uint8_t r_dupack; /* Dup ack count */ 63 uint8_t r_in_tmap; /* Flag to see if its in the r_tnext array */ 64 uint8_t r_limit_type; /* is this entry counted against a limit? */ 65 uint8_t r_just_ret : 1, /* After sending, the next pkt was just returned, i.e. limited */ 66 r_one_out_nr : 1, /* Special case 1 outstanding and not in recovery */ 67 r_avail : 6; 68 uint8_t r_resv[36]; 69 }; 70 71 RB_HEAD(rack_rb_tree_head, rack_sendmap); 72 TAILQ_HEAD(rack_head, rack_sendmap); 73 74 #define RACK_LIMIT_TYPE_SPLIT 1 75 76 /* 77 * We use the rate sample structure to 78 * assist in single sack/ack rate and rtt 79 * calculation. In the future we will expand 80 * this in BBR to do forward rate sample 81 * b/w estimation. 82 */ 83 #define RACK_RTT_EMPTY 0x00000001 /* Nothing yet stored in RTT's */ 84 #define RACK_RTT_VALID 0x00000002 /* We have at least one valid RTT */ 85 struct rack_rtt_sample { 86 uint32_t rs_flags; 87 uint32_t rs_rtt_lowest; 88 uint32_t rs_rtt_highest; 89 uint32_t rs_rtt_cnt; 90 uint32_t rs_us_rtt; 91 int32_t confidence; 92 uint64_t rs_rtt_tot; 93 uint16_t rs_us_rtrcnt; 94 }; 95 96 #define RACK_LOG_TYPE_ACK 0x01 97 #define RACK_LOG_TYPE_OUT 0x02 98 #define RACK_LOG_TYPE_TO 0x03 99 #define RACK_LOG_TYPE_ALLOC 0x04 100 #define RACK_LOG_TYPE_FREE 0x05 101 102 struct rack_log { 103 union { 104 struct rack_sendmap *rsm; /* For alloc/free */ 105 uint64_t sb_acc;/* For out/ack or t-o */ 106 }; 107 uint32_t th_seq; 108 uint32_t th_ack; 109 uint32_t snd_una; 110 uint32_t snd_nxt; /* th_win for TYPE_ACK */ 111 uint32_t snd_max; 112 uint32_t blk_start[4]; 113 uint32_t blk_end[4]; 114 uint8_t type; 115 uint8_t n_sackblks; 116 uint16_t len; /* Timeout T3=1, TLP=2, RACK=3 */ 117 }; 118 119 /* 120 * Magic numbers for logging timeout events if the 121 * logging is enabled. 122 */ 123 #define RACK_TO_FRM_TMR 1 124 #define RACK_TO_FRM_TLP 2 125 #define RACK_TO_FRM_RACK 3 126 #define RACK_TO_FRM_KEEP 4 127 #define RACK_TO_FRM_PERSIST 5 128 #define RACK_TO_FRM_DELACK 6 129 130 struct rack_opts_stats { 131 uint64_t tcp_rack_prop_rate; 132 uint64_t tcp_rack_prop; 133 uint64_t tcp_rack_tlp_reduce; 134 uint64_t tcp_rack_early_recov; 135 uint64_t tcp_rack_pace_always; 136 uint64_t tcp_rack_pace_reduce; 137 uint64_t tcp_rack_max_seg; 138 uint64_t tcp_rack_prr_sendalot; 139 uint64_t tcp_rack_min_to; 140 uint64_t tcp_rack_early_seg; 141 uint64_t tcp_rack_reord_thresh; 142 uint64_t tcp_rack_reord_fade; 143 uint64_t tcp_rack_tlp_thresh; 144 uint64_t tcp_rack_pkt_delay; 145 uint64_t tcp_rack_tlp_inc_var; 146 uint64_t tcp_tlp_use; 147 uint64_t tcp_rack_idle_reduce; 148 uint64_t tcp_rack_idle_reduce_high; 149 uint64_t rack_no_timer_in_hpts; 150 uint64_t tcp_rack_min_pace_seg; 151 uint64_t tcp_rack_pace_rate_ca; 152 uint64_t tcp_rack_rr; 153 uint64_t tcp_rack_do_detection; 154 uint64_t tcp_rack_rrr_no_conf_rate; 155 uint64_t tcp_initial_rate; 156 uint64_t tcp_initial_win; 157 uint64_t tcp_hdwr_pacing; 158 uint64_t tcp_gp_inc_ss; 159 uint64_t tcp_gp_inc_ca; 160 uint64_t tcp_gp_inc_rec; 161 uint64_t tcp_rack_force_max_seg; 162 uint64_t tcp_rack_pace_rate_ss; 163 uint64_t tcp_rack_pace_rate_rec; 164 /* Temp counters for dsack */ 165 uint64_t tcp_sack_path_1; 166 uint64_t tcp_sack_path_2a; 167 uint64_t tcp_sack_path_2b; 168 uint64_t tcp_sack_path_3; 169 uint64_t tcp_sack_path_4; 170 /* non temp counters */ 171 uint64_t tcp_rack_scwnd; 172 uint64_t tcp_rack_noprr; 173 uint64_t tcp_rack_cfg_rate; 174 uint64_t tcp_timely_dyn; 175 uint64_t tcp_rack_mbufq; 176 uint64_t tcp_fillcw; 177 uint64_t tcp_npush; 178 uint64_t tcp_lscwnd; 179 uint64_t tcp_profile; 180 }; 181 182 /* RTT shrink reasons */ 183 #define RACK_RTTS_INIT 0 184 #define RACK_RTTS_NEWRTT 1 185 #define RACK_RTTS_EXITPROBE 2 186 #define RACK_RTTS_ENTERPROBE 3 187 #define RACK_RTTS_REACHTARGET 4 188 #define RACK_RTTS_SEEHBP 5 189 #define RACK_RTTS_NOBACKOFF 6 190 #define RACK_RTTS_SAFETY 7 191 192 #define RACK_USE_BEG 1 193 #define RACK_USE_END 2 194 #define RACK_USE_END_OR_THACK 3 195 196 #define TLP_USE_ID 1 /* Internet draft behavior */ 197 #define TLP_USE_TWO_ONE 2 /* Use 2.1 behavior */ 198 #define TLP_USE_TWO_TWO 3 /* Use 2.2 behavior */ 199 #define RACK_MIN_BW 8000 /* 64kbps in Bps */ 200 201 #define MIN_GP_WIN 6 /* We need at least 6 MSS in a GP measurement */ 202 #ifdef _KERNEL 203 #define RACK_OPTS_SIZE (sizeof(struct rack_opts_stats)/sizeof(uint64_t)) 204 extern counter_u64_t rack_opts_arry[RACK_OPTS_SIZE]; 205 #define RACK_OPTS_ADD(name, amm) counter_u64_add(rack_opts_arry[(offsetof(struct rack_opts_stats, name)/sizeof(uint64_t))], (amm)) 206 #define RACK_OPTS_INC(name) RACK_OPTS_ADD(name, 1) 207 #endif 208 /* 209 * As we get each SACK we wade through the 210 * rc_map and mark off what is acked. 211 * We also increment rc_sacked as well. 212 * 213 * We also pay attention to missing entries 214 * based on the time and possibly mark them 215 * for retransmit. If we do and we are not already 216 * in recovery we enter recovery. In doing 217 * so we claer prr_delivered/holes_rxt and prr_sent_dur_rec. 218 * We also setup rc_next/rc_snd_nxt/rc_send_end so 219 * we will know where to send from. When not in 220 * recovery rc_next will be NULL and rc_snd_nxt should 221 * equal snd_max. 222 * 223 * Whenever we retransmit from recovery we increment 224 * rc_holes_rxt as we retran a block and mark it as retransmitted 225 * with the time it was sent. During non-recovery sending we 226 * add to our map and note the time down of any send expanding 227 * the rc_map at the tail and moving rc_snd_nxt up with snd_max. 228 * 229 * In recovery during SACK/ACK processing if a chunk has 230 * been retransmitted and it is now acked, we decrement rc_holes_rxt. 231 * When we retransmit from the scoreboard we use 232 * rc_next and rc_snd_nxt/rc_send_end to help us 233 * find what needs to be retran. 234 * 235 * To calculate pipe we simply take (snd_max - snd_una) + rc_holes_rxt 236 * This gets us the effect of RFC6675 pipe, counting twice for 237 * bytes retransmitted. 238 */ 239 240 #define TT_RACK_FR_TMR 0x2000 241 242 /* 243 * Locking for the rack control block. 244 * a) Locked by INP_WLOCK 245 * b) Locked by the hpts-mutex 246 * 247 */ 248 #define RACK_GP_HIST 4 /* How much goodput history do we maintain? */ 249 250 struct rack_control { 251 /* Second cache line 0x40 from tcp_rack */ 252 struct rack_rb_tree_head rc_mtree; /* Tree of all segments Lock(a) */ 253 struct rack_head rc_tmap; /* List in transmit order Lock(a) */ 254 struct rack_sendmap *rc_tlpsend; /* Remembered place for 255 * tlp_sending Lock(a) */ 256 struct rack_sendmap *rc_resend; /* something we have been asked to 257 * resend */ 258 uint32_t input_pkt; 259 uint32_t saved_input_pkt; 260 uint32_t rc_hpts_flags; 261 uint32_t rc_fixed_pacing_rate_ca; 262 uint32_t rc_fixed_pacing_rate_rec; 263 uint32_t rc_fixed_pacing_rate_ss; 264 uint32_t cwnd_to_use; /* The cwnd in use */ 265 uint32_t rc_timer_exp; /* If a timer ticks of expiry */ 266 uint32_t rc_rack_min_rtt; /* lowest RTT seen Lock(a) */ 267 uint32_t rc_rack_largest_cwnd; /* Largest CWND we have seen Lock(a) */ 268 269 /* Third Cache line 0x80 */ 270 struct rack_head rc_free; /* Allocation array */ 271 uint32_t rc_time_last_sent; /* Time we last sent some data and 272 * logged it Lock(a). */ 273 uint32_t rc_reorder_ts; /* Last time we saw reordering Lock(a) */ 274 275 uint32_t rc_tlp_new_data; /* we need to send new-data on a TLP 276 * Lock(a) */ 277 uint32_t rc_prr_out; /* bytes sent during recovery Lock(a) */ 278 279 uint32_t rc_prr_recovery_fs; /* recovery fs point Lock(a) */ 280 281 uint32_t rc_prr_sndcnt; /* Prr sndcnt Lock(a) */ 282 283 uint32_t rc_sacked; /* Tot sacked on scoreboard Lock(a) */ 284 uint32_t xxx_rc_last_tlp_seq; /* Last tlp sequence Lock(a) */ 285 286 uint32_t rc_prr_delivered; /* during recovery prr var Lock(a) */ 287 uint16_t rc_tlp_cnt_out; /* count of times we have sent a TLP without new data */ 288 uint16_t xxx_rc_tlp_seg_send_cnt; /* Number of times we have TLP sent 289 * rc_last_tlp_seq Lock(a) */ 290 291 uint32_t rc_loss_count; /* How many bytes have been retransmitted 292 * Lock(a) */ 293 uint32_t rc_reorder_fade; /* Socket option value Lock(a) */ 294 295 /* Forth cache line 0xc0 */ 296 /* Times */ 297 298 uint32_t rc_rack_tmit_time; /* Rack transmit time Lock(a) */ 299 uint32_t rc_holes_rxt; /* Tot retraned from scoreboard Lock(a) */ 300 301 /* Variables to track bad retransmits and recover */ 302 uint32_t rc_rsm_start; /* RSM seq number we retransmitted Lock(a) */ 303 uint32_t rc_cwnd_at; /* cwnd at the retransmit Lock(a) */ 304 305 uint32_t rc_ssthresh_at;/* ssthresh at the retransmit Lock(a) */ 306 uint32_t rc_num_maps_alloced; /* Number of map blocks (sacks) we 307 * have allocated */ 308 uint32_t rc_rcvtime; /* When we last received data */ 309 uint32_t rc_num_split_allocs; /* num split map entries allocated */ 310 311 uint32_t rc_last_output_to; 312 uint32_t rc_went_idle_time; 313 314 struct rack_sendmap *rc_sacklast; /* sack remembered place 315 * Lock(a) */ 316 317 struct rack_sendmap *rc_rsm_at_retran; /* Debug variable kept for 318 * cache line alignment 319 * Lock(a) */ 320 struct rack_sendmap *rc_first_appl; /* Pointer to first app limited */ 321 struct rack_sendmap *rc_end_appl; /* Pointer to last app limited */ 322 /* Cache line split 0x100 */ 323 struct sack_filter rack_sf; 324 /* Cache line split 0x140 */ 325 /* Flags for various things */ 326 uint32_t last_pacing_time; 327 uint32_t rc_pace_max_segs; 328 uint32_t rc_pace_min_segs; 329 uint32_t rc_app_limited_cnt; 330 uint16_t rack_per_of_gp_ss; /* 100 = 100%, so from 65536 = 655 x bw */ 331 uint16_t rack_per_of_gp_ca; /* 100 = 100%, so from 65536 = 655 x bw */ 332 uint16_t rack_per_of_gp_rec; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */ 333 uint16_t rack_per_of_gp_probertt; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */ 334 uint32_t rc_high_rwnd; 335 uint32_t ack_count; 336 uint32_t sack_count; 337 uint32_t sack_noextra_move; 338 uint32_t sack_moved_extra; 339 struct rack_rtt_sample rack_rs; 340 const struct tcp_hwrate_limit_table *crte; 341 uint32_t rc_agg_early; 342 uint32_t rc_agg_delayed; 343 uint32_t rc_tlp_rxt_last_time; 344 uint32_t rc_saved_cwnd; 345 uint32_t rc_gp_output_ts; 346 uint32_t rc_gp_cumack_ts; 347 struct timeval act_rcv_time; 348 struct timeval rc_last_time_decay; /* SAD time decay happened here */ 349 uint64_t gp_bw; 350 uint64_t init_rate; 351 #ifdef NETFLIX_SHARED_CWND 352 struct shared_cwnd *rc_scw; 353 #endif 354 uint64_t last_gp_comp_bw; 355 uint64_t last_max_bw; /* Our calculated max b/w last */ 356 struct time_filter_small rc_gp_min_rtt; 357 int32_t rc_rtt_diff; /* Timely style rtt diff of our gp_srtt */ 358 uint32_t rc_gp_srtt; /* Current GP srtt */ 359 uint32_t rc_prev_gp_srtt; /* Previous RTT */ 360 uint32_t rc_entry_gp_rtt; /* Entry to PRTT gp-rtt */ 361 uint32_t rc_loss_at_start; /* At measurement window where was our lost value */ 362 363 uint32_t forced_ack_ts; 364 uint32_t rc_lower_rtt_us_cts; /* Time our GP rtt was last lowered */ 365 uint32_t rc_time_probertt_entered; 366 uint32_t rc_time_probertt_starts; 367 uint32_t rc_lowest_us_rtt; 368 uint32_t rc_highest_us_rtt; 369 uint32_t rc_last_us_rtt; 370 uint32_t rc_time_of_last_probertt; 371 uint32_t rc_target_probertt_flight; 372 uint32_t rc_probertt_sndmax_atexit; /* Highest sent to in probe-rtt */ 373 uint32_t rc_gp_lowrtt; /* Lowest rtt seen during GPUT measurement */ 374 uint32_t rc_gp_high_rwnd; /* Highest rwnd seen during GPUT measurement */ 375 int32_t rc_scw_index; 376 uint32_t rc_tlp_threshold; /* Socket option value Lock(a) */ 377 uint16_t rc_early_recovery_segs; /* Socket option value Lock(a) */ 378 uint16_t rc_reorder_shift; /* Socket option value Lock(a) */ 379 uint16_t rc_pkt_delay; /* Socket option value Lock(a) */ 380 uint8_t rc_no_push_at_mrtt; /* No push when we exceed max rtt */ 381 uint8_t num_avg; /* average count before we go to normal decay */ 382 uint8_t rc_prop_rate; /* Socket option value Lock(a) */ 383 uint8_t rc_prop_reduce; /* Socket option value Lock(a) */ 384 uint8_t rc_tlp_cwnd_reduce; /* Socket option value Lock(a) */ 385 uint8_t rc_early_recovery; /* Socket option value Lock(a) */ 386 uint8_t rc_prr_sendalot;/* Socket option value Lock(a) */ 387 uint8_t rc_min_to; /* Socket option value Lock(a) */ 388 uint8_t rc_rate_sample_method; 389 uint8_t rc_gp_hist_idx; 390 }; 391 392 #define RACK_TIMELY_CNT_BOOST 5 /* At 5th increase boost */ 393 #define RACK_MINRTT_FILTER_TIM 10 /* Seconds */ 394 395 #ifdef _KERNEL 396 397 struct tcp_rack { 398 /* First cache line 0x00 */ 399 TAILQ_ENTRY(tcp_rack) r_hpts; /* hptsi queue next Lock(b) */ 400 int32_t(*r_substate) (struct mbuf *, struct tcphdr *, 401 struct socket *, struct tcpcb *, struct tcpopt *, 402 int32_t, int32_t, uint32_t, int, int, uint8_t); /* Lock(a) */ 403 struct tcpcb *rc_tp; /* The tcpcb Lock(a) */ 404 struct inpcb *rc_inp; /* The inpcb Lock(a) */ 405 uint32_t rc_free_cnt; /* Number of free entries on the rc_free list 406 * Lock(a) */ 407 uint32_t rc_rack_rtt; /* RACK-RTT Lock(a) */ 408 uint16_t r_mbuf_queue : 1, /* Do we do mbuf queue for non-paced */ 409 rtt_limit_mul : 4, /* muliply this by low rtt */ 410 r_limit_scw : 1, 411 r_avail_bits : 10; /* Available */ 412 413 uint16_t rc_user_set_max_segs; /* Socket option value Lock(a) */ 414 uint16_t forced_ack : 1, 415 rc_gp_incr : 1, 416 rc_gp_bwred : 1, 417 rc_gp_timely_inc_cnt : 3, 418 rc_gp_timely_dec_cnt : 3, 419 rc_not_backing_off: 1, 420 rc_highly_buffered: 1, /* The path is highly buffered */ 421 rc_dragged_bottom: 1, 422 rc_dack_mode : 1, /* Mac O/S emulation of d-ack */ 423 rc_dack_toggle : 1, /* For Mac O/S emulation of d-ack */ 424 pacing_longer_than_rtt : 1, 425 rc_gp_filled : 1; 426 uint8_t r_state; /* Current rack state Lock(a) */ 427 uint8_t rc_tmr_stopped : 7, 428 t_timers_stopped : 1; 429 uint8_t rc_enobuf : 7, /* count of enobufs on connection provides */ 430 rc_on_min_to : 1; 431 uint8_t r_timer_override : 1, /* hpts override Lock(a) */ 432 r_is_v6 : 1, /* V6 pcb Lock(a) */ 433 rc_in_persist : 1, 434 rc_tlp_in_progress : 1, 435 rc_always_pace : 1, /* Socket option value Lock(a) */ 436 rc_pace_to_cwnd : 1, 437 rc_pace_fill_if_rttin_range : 1, 438 xxx_avail_bits : 1; 439 uint8_t app_limited_needs_set : 1, 440 use_fixed_rate : 1, 441 rc_has_collapsed : 1, 442 r_rep_attack : 1, 443 r_rep_reverse : 1, 444 rack_hdrw_pacing : 1, /* We are doing Hardware pacing */ 445 rack_hdw_pace_ena : 1, /* Is hardware pacing enabled? */ 446 rack_attempt_hdwr_pace : 1; /* Did we attempt hdwr pacing (if allowed) */ 447 uint8_t rack_tlp_threshold_use : 3, /* only 1, 2 and 3 used so far */ 448 rack_rec_nonrxt_use_cr : 1, 449 rack_enable_scwnd : 1, 450 rack_attempted_scwnd : 1, 451 rack_no_prr : 1, 452 rack_scwnd_is_idle : 1; 453 uint8_t rc_allow_data_af_clo: 1, 454 delayed_ack : 1, 455 set_pacing_done_a_iw : 1, 456 use_rack_rr : 1, 457 alloc_limit_reported : 1, 458 sack_attack_disable : 1, 459 do_detection : 1, 460 rc_force_max_seg : 1; 461 uint8_t rack_cwnd_limited : 1, 462 r_early : 1, 463 r_late : 1, 464 r_running_early : 1, 465 r_running_late : 1, 466 r_wanted_output: 1, 467 r_rr_config : 2; 468 uint16_t rc_init_win : 8, 469 rc_gp_rtt_set : 1, 470 rc_gp_dyn_mul : 1, 471 rc_gp_saw_rec : 1, 472 rc_gp_saw_ca : 1, 473 rc_gp_saw_ss : 1, 474 rc_gp_no_rec_chg : 1, 475 in_probe_rtt : 1, 476 measure_saw_probe_rtt : 1; 477 /* Cache line 2 0x40 */ 478 struct rack_control r_ctl; 479 } __aligned(CACHE_LINE_SIZE); 480 481 #endif 482 #endif 483