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28 #ifndef _NETINET_TCP_RACK_H_
29 #define _NETINET_TCP_RACK_H_
31 #define RACK_ACKED 0x0001/* The remote endpoint acked this */
32 #define RACK_TO_REXT 0x0002/* A timeout occured on this sendmap entry */
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_SYN 0x0800/* SYN is on this guy */
43 #define RACK_SENT_W_DSACK 0x1000/* Sent with a dsack */
44 #define RACK_SENT_SP 0x2000/* sent in slow path */
45 #define RACK_SENT_FP 0x4000/* sent in fast path */
46 #define RACK_HAD_PUSH 0x8000/* Push was sent on original send */
47 #define RACK_NUM_OF_RETRANS 3
49 #define RACK_INITIAL_RTO 1000000 /* 1 second in microseconds */
51 #define RACK_REQ_AVG 3 /* Must be less than 256 */
54 TAILQ_ENTRY(rack_sendmap) r_tnext; /* Time of transmit based next */
55 uint32_t r_start; /* Sequence number of the segment */
56 uint32_t r_end; /* End seq, this is 1 beyond actually */
57 uint32_t r_rtr_bytes; /* How many bytes have been retransmitted */
58 uint16_t r_rtr_cnt; /* Retran count, index this -1 to get time
60 uint16_t r_flags; /* Flags as defined above */
64 uint32_t r_nseq_appl; /* If this one is app limited, this is the nxt seq limited */
65 uint8_t r_dupack; /* Dup ack count */
66 uint8_t r_in_tmap; /* Flag to see if its in the r_tnext array */
67 uint8_t r_limit_type; /* is this entry counted against a limit? */
68 uint8_t r_just_ret : 1, /* After sending, the next pkt was just returned, i.e. limited */
69 r_one_out_nr : 1, /* Special case 1 outstanding and not in recovery */
70 r_no_rtt_allowed : 1, /* No rtt measurement allowed */
73 uint64_t r_tim_lastsent[RACK_NUM_OF_RETRANS];
74 uint64_t r_ack_arrival; /* This is the time of ack-arrival (if SACK'd) */
75 RB_ENTRY(rack_sendmap) r_next; /* RB Tree next */
78 struct deferred_opt_list {
79 TAILQ_ENTRY(deferred_opt_list) next;
85 * Timestamps in the rack sendmap are now moving to be
86 * uint64_t's. This means that if you want a uint32_t
87 * usec timestamp (the old usecond timestamp) you simply have
88 * to cast it to uint32_t. The reason we do this is not for
89 * wrap, but we need to get back, at times, to the millisecond
90 * timestamp that is used in the TSTMP option. To do this we
91 * can use the rack_ts_to_msec() inline below which can take
92 * the 64bit ts and make into the correct timestamp millisecond
93 * wise. Thats not possible with the 32bit usecond timestamp since
94 * the seconds wrap too quickly to cover all bases.
96 * There are quite a few places in rack where I simply cast
97 * back to uint32_t and then end up using the TSTMP_XX()
98 * macros. This is ok, but we could do simple compares if
99 * we ever decided to move all of those variables to 64 bits
104 rack_to_usec_ts(struct timeval *tv)
106 return ((tv->tv_sec * HPTS_USEC_IN_SEC) + tv->tv_usec);
110 rack_ts_to_msec(uint64_t ts)
112 return((uint32_t)(ts / HPTS_MSEC_IN_SEC));
116 RB_HEAD(rack_rb_tree_head, rack_sendmap);
117 TAILQ_HEAD(rack_head, rack_sendmap);
118 TAILQ_HEAD(def_opt_head, deferred_opt_list);
120 /* Map change logging */
121 #define MAP_MERGE 0x01
122 #define MAP_SPLIT 0x02
124 #define MAP_SACK_M1 0x04
125 #define MAP_SACK_M2 0x05
126 #define MAP_SACK_M3 0x06
127 #define MAP_SACK_M4 0x07
128 #define MAP_SACK_M5 0x08
129 #define MAP_FREE 0x09
130 #define MAP_TRIM_HEAD 0x0a
132 #define RACK_LIMIT_TYPE_SPLIT 1
135 * We use the rate sample structure to
136 * assist in single sack/ack rate and rtt
137 * calculation. In the future we will expand
138 * this in BBR to do forward rate sample
141 #define RACK_RTT_EMPTY 0x00000001 /* Nothing yet stored in RTT's */
142 #define RACK_RTT_VALID 0x00000002 /* We have at least one valid RTT */
143 struct rack_rtt_sample {
145 uint32_t rs_rtt_lowest;
146 uint32_t rs_rtt_highest;
151 uint16_t rs_us_rtrcnt;
154 #define RACK_LOG_TYPE_ACK 0x01
155 #define RACK_LOG_TYPE_OUT 0x02
156 #define RACK_LOG_TYPE_TO 0x03
157 #define RACK_LOG_TYPE_ALLOC 0x04
158 #define RACK_LOG_TYPE_FREE 0x05
162 struct rack_sendmap *rsm; /* For alloc/free */
163 uint64_t sb_acc;/* For out/ack or t-o */
168 uint32_t snd_nxt; /* th_win for TYPE_ACK */
170 uint32_t blk_start[4];
174 uint16_t len; /* Timeout T3=1, TLP=2, RACK=3 */
178 * Magic numbers for logging timeout events if the
179 * logging is enabled.
181 #define RACK_TO_FRM_TMR 1
182 #define RACK_TO_FRM_TLP 2
183 #define RACK_TO_FRM_RACK 3
184 #define RACK_TO_FRM_KEEP 4
185 #define RACK_TO_FRM_PERSIST 5
186 #define RACK_TO_FRM_DELACK 6
188 struct rack_opts_stats {
189 uint64_t tcp_rack_tlp_reduce;
190 uint64_t tcp_rack_pace_always;
191 uint64_t tcp_rack_pace_reduce;
192 uint64_t tcp_rack_max_seg;
193 uint64_t tcp_rack_prr_sendalot;
194 uint64_t tcp_rack_min_to;
195 uint64_t tcp_rack_early_seg;
196 uint64_t tcp_rack_reord_thresh;
197 uint64_t tcp_rack_reord_fade;
198 uint64_t tcp_rack_tlp_thresh;
199 uint64_t tcp_rack_pkt_delay;
200 uint64_t tcp_rack_tlp_inc_var;
201 uint64_t tcp_tlp_use;
202 uint64_t tcp_rack_idle_reduce;
203 uint64_t tcp_rack_idle_reduce_high;
204 uint64_t rack_no_timer_in_hpts;
205 uint64_t tcp_rack_min_pace_seg;
206 uint64_t tcp_rack_pace_rate_ca;
207 uint64_t tcp_rack_rr;
208 uint64_t tcp_rack_do_detection;
209 uint64_t tcp_rack_rrr_no_conf_rate;
210 uint64_t tcp_initial_rate;
211 uint64_t tcp_initial_win;
212 uint64_t tcp_hdwr_pacing;
213 uint64_t tcp_gp_inc_ss;
214 uint64_t tcp_gp_inc_ca;
215 uint64_t tcp_gp_inc_rec;
216 uint64_t tcp_rack_force_max_seg;
217 uint64_t tcp_rack_pace_rate_ss;
218 uint64_t tcp_rack_pace_rate_rec;
219 /* Temp counters for dsack */
220 uint64_t tcp_sack_path_1;
221 uint64_t tcp_sack_path_2a;
222 uint64_t tcp_sack_path_2b;
223 uint64_t tcp_sack_path_3;
224 uint64_t tcp_sack_path_4;
225 /* non temp counters */
226 uint64_t tcp_rack_scwnd;
227 uint64_t tcp_rack_noprr;
228 uint64_t tcp_rack_cfg_rate;
229 uint64_t tcp_timely_dyn;
230 uint64_t tcp_rack_mbufq;
234 uint64_t tcp_profile;
235 uint64_t tcp_hdwr_rate_cap;
236 uint64_t tcp_pacing_rate_cap;
237 uint64_t tcp_pacing_up_only;
238 uint64_t tcp_use_cmp_acks;
239 uint64_t tcp_rack_abc_val;
240 uint64_t tcp_rec_abc_val;
241 uint64_t tcp_rack_measure_cnt;
242 uint64_t tcp_rack_delayed_ack;
243 uint64_t tcp_rack_rtt_use;
244 uint64_t tcp_data_after_close;
245 uint64_t tcp_defer_opt;
246 uint64_t tcp_rack_fastrsm_hack;
247 uint64_t tcp_rack_beta;
248 uint64_t tcp_rack_beta_ecn;
249 uint64_t tcp_rack_timer_slop;
250 uint64_t tcp_rack_dsack_opt;
253 /* RTT shrink reasons */
254 #define RACK_RTTS_INIT 0
255 #define RACK_RTTS_NEWRTT 1
256 #define RACK_RTTS_EXITPROBE 2
257 #define RACK_RTTS_ENTERPROBE 3
258 #define RACK_RTTS_REACHTARGET 4
259 #define RACK_RTTS_SEEHBP 5
260 #define RACK_RTTS_NOBACKOFF 6
261 #define RACK_RTTS_SAFETY 7
263 #define RACK_USE_BEG 1
264 #define RACK_USE_END 2
265 #define RACK_USE_END_OR_THACK 3
267 #define TLP_USE_ID 1 /* Internet draft behavior */
268 #define TLP_USE_TWO_ONE 2 /* Use 2.1 behavior */
269 #define TLP_USE_TWO_TWO 3 /* Use 2.2 behavior */
270 #define RACK_MIN_BW 8000 /* 64kbps in Bps */
272 /* Rack quality indicators for GPUT measurements */
273 #define RACK_QUALITY_NONE 0 /* No quality stated */
274 #define RACK_QUALITY_HIGH 1 /* A normal measurement of a GP RTT */
275 #define RACK_QUALITY_APPLIMITED 2 /* An app limited case that may be of lower quality */
276 #define RACK_QUALITY_PERSIST 3 /* A measurement where we went into persists */
277 #define RACK_QUALITY_PROBERTT 4 /* A measurement where we went into or exited probe RTT */
278 #define RACK_QUALITY_ALLACKED 5 /* All data is now acknowledged */
281 #define MIN_GP_WIN 6 /* We need at least 6 MSS in a GP measurement */
283 #define RACK_OPTS_SIZE (sizeof(struct rack_opts_stats)/sizeof(uint64_t))
284 extern counter_u64_t rack_opts_arry[RACK_OPTS_SIZE];
285 #define RACK_OPTS_ADD(name, amm) counter_u64_add(rack_opts_arry[(offsetof(struct rack_opts_stats, name)/sizeof(uint64_t))], (amm))
286 #define RACK_OPTS_INC(name) RACK_OPTS_ADD(name, 1)
289 * As we get each SACK we wade through the
290 * rc_map and mark off what is acked.
291 * We also increment rc_sacked as well.
293 * We also pay attention to missing entries
294 * based on the time and possibly mark them
295 * for retransmit. If we do and we are not already
296 * in recovery we enter recovery. In doing
297 * so we claer prr_delivered/holes_rxt and prr_sent_dur_rec.
298 * We also setup rc_next/rc_snd_nxt/rc_send_end so
299 * we will know where to send from. When not in
300 * recovery rc_next will be NULL and rc_snd_nxt should
303 * Whenever we retransmit from recovery we increment
304 * rc_holes_rxt as we retran a block and mark it as retransmitted
305 * with the time it was sent. During non-recovery sending we
306 * add to our map and note the time down of any send expanding
307 * the rc_map at the tail and moving rc_snd_nxt up with snd_max.
309 * In recovery during SACK/ACK processing if a chunk has
310 * been retransmitted and it is now acked, we decrement rc_holes_rxt.
311 * When we retransmit from the scoreboard we use
312 * rc_next and rc_snd_nxt/rc_send_end to help us
313 * find what needs to be retran.
315 * To calculate pipe we simply take (snd_max - snd_una) + rc_holes_rxt
316 * This gets us the effect of RFC6675 pipe, counting twice for
317 * bytes retransmitted.
320 #define TT_RACK_FR_TMR 0x2000
323 * Locking for the rack control block.
324 * a) Locked by INP_WLOCK
325 * b) Locked by the hpts-mutex
328 #define RACK_GP_HIST 4 /* How much goodput history do we maintain? */
330 #define RACK_NUM_FSB_DEBUG 16
332 struct rack_fast_send_blk {
333 uint32_t left_to_send;
334 uint16_t tcp_ip_hdr_len;
344 uint32_t rfo_apply_push : 1,
349 struct rack_control {
350 /* Second cache line 0x40 from tcp_rack */
351 struct rack_rb_tree_head rc_mtree; /* Tree of all segments Lock(a) */
352 struct rack_head rc_tmap; /* List in transmit order Lock(a) */
353 struct rack_sendmap *rc_tlpsend; /* Remembered place for
354 * tlp_sending Lock(a) */
355 struct rack_sendmap *rc_resend; /* something we have been asked to
357 struct rack_fast_send_blk fsb; /* The fast-send block */
360 uint32_t saved_input_pkt;
361 uint32_t rc_hpts_flags;
362 uint32_t rc_fixed_pacing_rate_ca;
363 uint32_t rc_fixed_pacing_rate_rec;
364 uint32_t rc_fixed_pacing_rate_ss;
365 uint32_t cwnd_to_use; /* The cwnd in use */
366 uint32_t rc_timer_exp; /* If a timer ticks of expiry */
367 uint32_t rc_rack_min_rtt; /* lowest RTT seen Lock(a) */
368 uint32_t rc_rack_largest_cwnd; /* Largest CWND we have seen Lock(a) */
370 /* Third Cache line 0x80 */
371 struct rack_head rc_free; /* Allocation array */
372 uint64_t last_hw_bw_req;
373 uint64_t crte_prev_rate;
374 uint64_t bw_rate_cap;
375 uint32_t rc_time_last_sent; /* Time we last sent some data and
376 * logged it Lock(a). */
377 uint32_t rc_reorder_ts; /* Last time we saw reordering Lock(a) */
379 uint32_t rc_tlp_new_data; /* we need to send new-data on a TLP
381 uint32_t rc_prr_out; /* bytes sent during recovery Lock(a) */
383 uint32_t rc_prr_recovery_fs; /* recovery fs point Lock(a) */
385 uint32_t rc_prr_sndcnt; /* Prr sndcnt Lock(a) */
387 uint32_t rc_sacked; /* Tot sacked on scoreboard Lock(a) */
388 uint32_t last_sent_tlp_seq; /* Last tlp sequence that was retransmitted Lock(a) */
390 uint32_t rc_prr_delivered; /* during recovery prr var Lock(a) */
391 uint16_t rc_tlp_cnt_out; /* count of times we have sent a TLP without new data */
392 uint16_t last_sent_tlp_len; /* Number of bytes in the last sent tlp */
394 uint32_t rc_loss_count; /* How many bytes have been retransmitted
396 uint32_t rc_reorder_fade; /* Socket option value Lock(a) */
398 /* Forth cache line 0xc0 */
401 uint32_t rc_rack_tmit_time; /* Rack transmit time Lock(a) */
402 uint32_t rc_holes_rxt; /* Tot retraned from scoreboard Lock(a) */
404 /* Variables to track bad retransmits and recover */
405 uint32_t rc_rsm_start; /* RSM seq number we retransmitted Lock(a) */
406 uint32_t rc_cwnd_at; /* cwnd at the retransmit Lock(a) */
408 uint32_t rc_ssthresh_at;/* ssthresh at the retransmit Lock(a) */
409 uint32_t rc_num_maps_alloced; /* Number of map blocks (sacks) we
411 uint32_t rc_rcvtime; /* When we last received data */
412 uint32_t rc_num_split_allocs; /* num split map entries allocated */
414 uint32_t rc_last_output_to;
415 uint32_t rc_went_idle_time;
417 struct rack_sendmap *rc_sacklast; /* sack remembered place
420 struct rack_sendmap *rc_rsm_at_retran; /* Debug variable kept for
421 * cache line alignment
423 struct rack_sendmap *rc_first_appl; /* Pointer to first app limited */
424 struct rack_sendmap *rc_end_appl; /* Pointer to last app limited */
425 /* Cache line split 0x100 */
426 struct sack_filter rack_sf;
427 /* Cache line split 0x140 */
428 /* Flags for various things */
429 uint32_t last_pacing_time;
430 uint32_t rc_pace_max_segs;
431 uint32_t rc_pace_min_segs;
432 uint32_t rc_app_limited_cnt;
433 uint16_t rack_per_of_gp_ss; /* 100 = 100%, so from 65536 = 655 x bw */
434 uint16_t rack_per_of_gp_ca; /* 100 = 100%, so from 65536 = 655 x bw */
435 uint16_t rack_per_of_gp_rec; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */
436 uint16_t rack_per_of_gp_probertt; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */
437 uint32_t rc_high_rwnd;
440 uint32_t sack_noextra_move;
441 uint32_t sack_moved_extra;
442 struct rack_rtt_sample rack_rs;
443 const struct tcp_hwrate_limit_table *crte;
444 uint32_t rc_agg_early;
445 uint32_t rc_agg_delayed;
446 uint32_t rc_tlp_rxt_last_time;
447 uint32_t rc_saved_cwnd;
448 uint64_t rc_gp_output_ts; /* chg*/
449 uint64_t rc_gp_cumack_ts; /* chg*/
450 struct timeval act_rcv_time;
451 struct timeval rc_last_time_decay; /* SAD time decay happened here */
454 #ifdef NETFLIX_SHARED_CWND
455 struct shared_cwnd *rc_scw;
457 uint64_t last_gp_comp_bw;
458 uint64_t last_max_bw; /* Our calculated max b/w last */
459 struct time_filter_small rc_gp_min_rtt;
460 struct def_opt_head opt_list;
461 int32_t rc_rtt_diff; /* Timely style rtt diff of our gp_srtt */
462 uint32_t rc_gp_srtt; /* Current GP srtt */
463 uint32_t rc_prev_gp_srtt; /* Previous RTT */
464 uint32_t rc_entry_gp_rtt; /* Entry to PRTT gp-rtt */
465 uint32_t rc_loss_at_start; /* At measurement window where was our lost value */
467 uint32_t dsack_round_end; /* In a round of seeing a DSACK */
468 uint32_t num_dsack; /* Count of dsack's seen (1 per window)*/
469 uint32_t forced_ack_ts;
470 uint32_t rc_lower_rtt_us_cts; /* Time our GP rtt was last lowered */
471 uint32_t rc_time_probertt_entered;
472 uint32_t rc_time_probertt_starts;
473 uint32_t rc_lowest_us_rtt;
474 uint32_t rc_highest_us_rtt;
475 uint32_t rc_last_us_rtt;
476 uint32_t rc_time_of_last_probertt;
477 uint32_t rc_target_probertt_flight;
478 uint32_t rc_probertt_sndmax_atexit; /* Highest sent to in probe-rtt */
479 uint32_t rc_cwnd_at_erec;
480 uint32_t rc_ssthresh_at_erec;
481 uint32_t dsack_byte_cnt;
482 uint32_t retran_during_recovery;
483 uint32_t rc_gp_lowrtt; /* Lowest rtt seen during GPUT measurement */
484 uint32_t rc_gp_high_rwnd; /* Highest rwnd seen during GPUT measurement */
485 uint32_t rc_snd_max_at_rto; /* For non-sack when the RTO occured what was snd-max */
486 uint32_t rc_out_at_rto;
487 int32_t rc_scw_index;
488 uint32_t rc_tlp_threshold; /* Socket option value Lock(a) */
489 uint32_t rc_last_timeout_snduna;
490 uint32_t last_tlp_acked_start;
491 uint32_t last_tlp_acked_end;
492 uint32_t challenge_ack_ts;
493 uint32_t challenge_ack_cnt;
494 uint32_t rc_min_to; /* Socket option value Lock(a) */
495 uint32_t rc_pkt_delay; /* Socket option value Lock(a) */
496 struct newreno rc_saved_beta; /*
498 * rc_saved_cc are the values we have had
499 * set by the user, if pacing is not happening
500 * (i.e. its early and we have not turned on yet
501 * or it was turned off). The minute pacing
502 * is turned on we pull out the values currently
503 * being used by newreno and replace them with
504 * these values, then save off the old values here,
505 * we also set the flag (if ecn_beta is set) to make
506 * new_reno do less of a backoff for ecn (think abe).
508 uint16_t rc_early_recovery_segs; /* Socket option value Lock(a) */
509 uint16_t rc_reorder_shift; /* Socket option value Lock(a) */
510 uint8_t dsack_persist;
511 uint8_t rc_no_push_at_mrtt; /* No push when we exceed max rtt */
512 uint8_t num_measurements; /* Number of measurements (up to 0xff, we freeze at 0xff) */
513 uint8_t req_measurements; /* How many measurements are required? */
514 uint8_t rc_tlp_cwnd_reduce; /* Socket option value Lock(a) */
515 uint8_t rc_prr_sendalot;/* Socket option value Lock(a) */
516 uint8_t rc_rate_sample_method;
517 uint8_t rc_gp_hist_idx;
521 #define RACK_TIMELY_CNT_BOOST 5 /* At 5th increase boost */
522 #define RACK_MINRTT_FILTER_TIM 10 /* Seconds */
527 /* First cache line 0x00 */
528 TAILQ_ENTRY(tcp_rack) r_hpts; /* hptsi queue next Lock(b) */
529 int32_t(*r_substate) (struct mbuf *, struct tcphdr *,
530 struct socket *, struct tcpcb *, struct tcpopt *,
531 int32_t, int32_t, uint32_t, int, int, uint8_t); /* Lock(a) */
532 struct tcpcb *rc_tp; /* The tcpcb Lock(a) */
533 struct inpcb *rc_inp; /* The inpcb Lock(a) */
534 uint8_t rc_free_cnt; /* Number of free entries on the rc_free list
536 uint8_t client_bufferlvl; /* 0 - 5 normaly, less than or at 2 means its real low */
537 uint8_t no_prr_addback : 1,
541 rc_ack_can_sendout_data: 1, /*
542 * If set it will override pacing restrictions on not sending
543 * data when the pacing timer is running. I.e. you set this
544 * and an ACK will send data. Default is off and its only used
545 * without pacing when we are doing 5G speed up for there
548 rc_pacing_cc_set: 1, /*
549 * If we are pacing (pace_always=1) and we have reached the
550 * point where we start pacing (fixed or gp has reached its
551 * magic gp_ready state) this flag indicates we have set in
552 * values to effect CC's backoff's. If pacing is turned off
553 * then we must restore the values saved in rc_saved_beta,
554 * if its going to gp_ready we need to copy the values into
555 * the CC module and set our flags.
557 * Note this only happens if the cc name is newreno (CCALGONAME_NEWRENO).
560 rc_rack_tmr_std_based :1,
561 rc_rack_use_dsack: 1;
562 uint8_t rc_dsack_round_seen: 1,
563 rc_last_tlp_acked_set: 1,
564 rc_last_tlp_past_cumack: 1,
565 rc_last_sent_tlp_seq_valid: 1,
566 rc_last_sent_tlp_past_cumack: 1,
568 uint32_t rc_rack_rtt; /* RACK-RTT Lock(a) */
569 uint16_t r_mbuf_queue : 1, /* Do we do mbuf queue for non-paced */
570 rtt_limit_mul : 4, /* muliply this by low rtt */
572 r_must_retran : 1, /* For non-sack customers we hit an RTO and new data should be resends */
573 r_use_cmp_ack: 1, /* Do we use compressed acks */
574 r_ent_rec_ns: 1, /* We entered recovery and have not sent */
575 r_might_revert: 1, /* Flag to find out if we might need to revert */
576 r_fast_output: 1, /* Fast output is in progress we can skip the bulk of rack_output */
578 r_rack_hw_rate_caps: 1,
583 uint8_t rc_user_set_max_segs; /* Socket option value Lock(a) */
584 uint8_t rc_labc; /* Appropriate Byte Counting Value */
585 uint16_t forced_ack : 1,
588 rc_gp_timely_inc_cnt : 3,
589 rc_gp_timely_dec_cnt : 3,
590 r_use_labc_for_rec: 1,
591 rc_highly_buffered: 1, /* The path is highly buffered */
592 rc_dragged_bottom: 1,
593 rc_dack_mode : 1, /* Mac O/S emulation of d-ack */
594 rc_dack_toggle : 1, /* For Mac O/S emulation of d-ack */
595 pacing_longer_than_rtt : 1,
597 uint8_t r_state; /* Current rack state Lock(a) */
598 uint8_t rc_tmr_stopped : 7,
599 t_timers_stopped : 1;
600 uint8_t rc_enobuf : 7, /* count of enobufs on connection provides */
602 uint8_t r_timer_override : 1, /* hpts override Lock(a) */
603 r_is_v6 : 1, /* V6 pcb Lock(a) */
605 rc_tlp_in_progress : 1,
606 rc_always_pace : 1, /* Socket option value Lock(a) */
608 rc_pace_fill_if_rttin_range : 1,
609 rc_srtt_measure_made : 1;
610 uint8_t app_limited_needs_set : 1,
612 rc_has_collapsed : 1,
615 rack_hdrw_pacing : 1, /* We are doing Hardware pacing */
616 rack_hdw_pace_ena : 1, /* Is hardware pacing enabled? */
617 rack_attempt_hdwr_pace : 1; /* Did we attempt hdwr pacing (if allowed) */
618 uint8_t rack_tlp_threshold_use : 3, /* only 1, 2 and 3 used so far */
619 rack_rec_nonrxt_use_cr : 1,
620 rack_enable_scwnd : 1,
621 rack_attempted_scwnd : 1,
623 rack_scwnd_is_idle : 1;
624 uint8_t rc_allow_data_af_clo: 1,
626 set_pacing_done_a_iw : 1,
628 alloc_limit_reported : 1,
629 sack_attack_disable : 1,
631 rc_force_max_seg : 1;
632 uint8_t rack_cwnd_limited : 1,
639 uint16_t rc_init_win : 8,
645 rc_gp_no_rec_chg : 1,
647 measure_saw_probe_rtt : 1;
648 /* Cache line 2 0x40 */
649 struct rack_control r_ctl;
650 } __aligned(CACHE_LINE_SIZE);