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28 #ifndef _NETINET_TCP_RACK_H_
29 #define _NETINET_TCP_RACK_H_
31 #define RACK_ACKED 0x000001/* The remote endpoint acked this */
32 #define RACK_TO_REXT 0x000002/* A timeout occurred on this sendmap entry */
33 #define RACK_DEFERRED 0x000004/* We can't use this for RTT calc - not used */
34 #define RACK_OVERMAX 0x000008/* We have more retran's then we can fit */
35 #define RACK_SACK_PASSED 0x000010/* A sack was done above this block */
36 #define RACK_WAS_SACKPASS 0x000020/* We retransmitted due to SACK pass */
37 #define RACK_HAS_FIN 0x000040/* segment is sent with fin */
38 #define RACK_TLP 0x000080/* segment sent as tail-loss-probe */
39 #define RACK_RWND_COLLAPSED 0x000100/* The peer collapsed the rwnd on the segment */
40 #define RACK_APP_LIMITED 0x000200/* We went app limited after this send */
41 #define RACK_WAS_ACKED 0x000400/* a RTO undid the ack, but it already had a rtt calc done */
42 #define RACK_HAS_SYN 0x000800/* SYN is on this guy */
43 #define RACK_SENT_W_DSACK 0x001000/* Sent with a dsack */
44 #define RACK_SENT_SP 0x002000/* sent in slow path */
45 #define RACK_SENT_FP 0x004000/* sent in fast path */
46 #define RACK_HAD_PUSH 0x008000/* Push was sent on original send */
47 #define RACK_MUST_RXT 0x010000/* We must retransmit this rsm (non-sack/mtu chg)*/
48 #define RACK_IN_GP_WIN 0x020000/* Send was in GP window when sent */
49 #define RACK_SHUFFLED 0x040000/* The RSM was shuffled some data from one to another */
50 #define RACK_MERGED 0x080000/* The RSM was merged */
51 #define RACK_PMTU_CHG 0x100000/* The path mtu changed on this guy */
52 #define RACK_STRADDLE 0x200000/* The seq straddles the bucket line */
53 #define RACK_NUM_OF_RETRANS 3
55 #define RACK_INITIAL_RTO 1000000 /* 1 second in microseconds */
57 #define RACK_REQ_AVG 3 /* Must be less than 256 */
60 TAILQ_ENTRY(rack_sendmap) next;
61 TAILQ_ENTRY(rack_sendmap) r_tnext; /* Time of transmit based next */
63 uint32_t r_start; /* Sequence number of the segment */
64 uint32_t r_end; /* End seq, this is 1 beyond actually */
65 uint32_t r_rtr_bytes; /* How many bytes have been retransmitted */
66 uint32_t r_flags : 24, /* Flags as defined above */
67 r_rtr_cnt : 8; /* Retran count, index this -1 to get time */
70 uint32_t orig_m_len; /* The original mbuf len when we sent (can update) */
71 uint32_t orig_t_space; /* The original trailing space when we sent (can update) */
72 uint32_t r_nseq_appl; /* If this one is app limited, this is the nxt seq limited */
73 uint8_t r_dupack; /* Dup ack count */
74 uint8_t r_in_tmap; /* Flag to see if its in the r_tnext array */
75 uint8_t r_limit_type; /* is this entry counted against a limit? */
76 uint8_t r_just_ret : 1, /* After sending, the next pkt was just returned, i.e. limited */
77 r_one_out_nr : 1, /* Special case 1 outstanding and not in recovery */
78 r_no_rtt_allowed : 1, /* No rtt measurement allowed */
81 uint64_t r_tim_lastsent[RACK_NUM_OF_RETRANS];
82 uint64_t r_ack_arrival; /* This is the time of ack-arrival (if SACK'd) */
83 uint32_t r_fas; /* Flight at send */
84 uint8_t r_bas; /* The burst size (burst at send = bas) */
87 struct deferred_opt_list {
88 TAILQ_ENTRY(deferred_opt_list) next;
94 * Timestamps in the rack sendmap are now moving to be
95 * uint64_t's. This means that if you want a uint32_t
96 * usec timestamp (the old usecond timestamp) you simply have
97 * to cast it to uint32_t. The reason we do this is not for
98 * wrap, but we need to get back, at times, to the millisecond
99 * timestamp that is used in the TSTMP option. To do this we
100 * can use the rack_ts_to_msec() inline below which can take
101 * the 64bit ts and make into the correct timestamp millisecond
102 * wise. Thats not possible with the 32bit usecond timestamp since
103 * the seconds wrap too quickly to cover all bases.
105 * There are quite a few places in rack where I simply cast
106 * back to uint32_t and then end up using the TSTMP_XX()
107 * macros. This is ok, but we could do simple compares if
108 * we ever decided to move all of those variables to 64 bits
112 static inline uint64_t
113 rack_to_usec_ts(struct timeval *tv)
115 return ((tv->tv_sec * HPTS_USEC_IN_SEC) + tv->tv_usec);
118 static inline uint32_t
119 rack_ts_to_msec(uint64_t ts)
121 return((uint32_t)(ts / HPTS_MSEC_IN_SEC));
125 RB_HEAD(rack_rb_tree_head, rack_sendmap);
126 TAILQ_HEAD(rack_head, rack_sendmap);
127 TAILQ_HEAD(def_opt_head, deferred_opt_list);
129 /* Map change logging */
130 #define MAP_MERGE 0x01
131 #define MAP_SPLIT 0x02
133 #define MAP_SACK_M1 0x04
134 #define MAP_SACK_M2 0x05
135 #define MAP_SACK_M3 0x06
136 #define MAP_SACK_M4 0x07
137 #define MAP_SACK_M5 0x08
138 #define MAP_FREE 0x09
139 #define MAP_TRIM_HEAD 0x0a
141 #define RACK_LIMIT_TYPE_SPLIT 1
144 * We use the rate sample structure to
145 * assist in single sack/ack rate and rtt
146 * calculation. In the future we will expand
147 * this in BBR to do forward rate sample
150 #define RACK_RTT_EMPTY 0x00000001 /* Nothing yet stored in RTT's */
151 #define RACK_RTT_VALID 0x00000002 /* We have at least one valid RTT */
152 struct rack_rtt_sample {
154 uint32_t rs_rtt_lowest;
155 uint32_t rs_rtt_highest;
160 uint16_t rs_us_rtrcnt;
163 #define RACK_LOG_TYPE_ACK 0x01
164 #define RACK_LOG_TYPE_OUT 0x02
165 #define RACK_LOG_TYPE_TO 0x03
166 #define RACK_LOG_TYPE_ALLOC 0x04
167 #define RACK_LOG_TYPE_FREE 0x05
170 * Magic numbers for logging timeout events if the
171 * logging is enabled.
173 #define RACK_TO_FRM_TMR 1
174 #define RACK_TO_FRM_TLP 2
175 #define RACK_TO_FRM_RACK 3
176 #define RACK_TO_FRM_KEEP 4
177 #define RACK_TO_FRM_PERSIST 5
178 #define RACK_TO_FRM_DELACK 6
180 struct rack_opts_stats {
181 uint64_t tcp_rack_tlp_reduce;
182 uint64_t tcp_rack_pace_always;
183 uint64_t tcp_rack_pace_reduce;
184 uint64_t tcp_rack_max_seg;
185 uint64_t tcp_rack_prr_sendalot;
186 uint64_t tcp_rack_min_to;
187 uint64_t tcp_rack_early_seg;
188 uint64_t tcp_rack_reord_thresh;
189 uint64_t tcp_rack_reord_fade;
190 uint64_t tcp_rack_tlp_thresh;
191 uint64_t tcp_rack_pkt_delay;
192 uint64_t tcp_rack_tlp_inc_var;
193 uint64_t tcp_tlp_use;
194 uint64_t tcp_rack_idle_reduce;
195 uint64_t tcp_rack_idle_reduce_high;
196 uint64_t rack_no_timer_in_hpts;
197 uint64_t tcp_rack_min_pace_seg;
198 uint64_t tcp_rack_pace_rate_ca;
199 uint64_t tcp_rack_rr;
200 uint64_t tcp_rack_do_detection;
201 uint64_t tcp_rack_rrr_no_conf_rate;
202 uint64_t tcp_initial_rate;
203 uint64_t tcp_initial_win;
204 uint64_t tcp_hdwr_pacing;
205 uint64_t tcp_gp_inc_ss;
206 uint64_t tcp_gp_inc_ca;
207 uint64_t tcp_gp_inc_rec;
208 uint64_t tcp_rack_force_max_seg;
209 uint64_t tcp_rack_pace_rate_ss;
210 uint64_t tcp_rack_pace_rate_rec;
211 /* Temp counters for dsack */
212 uint64_t tcp_sack_path_1; /* not used */
213 uint64_t tcp_sack_path_2a; /* not used */
214 uint64_t tcp_sack_path_2b; /* not used */
215 uint64_t tcp_sack_path_3; /* not used */
216 uint64_t tcp_sack_path_4; /* not used */
217 /* non temp counters */
218 uint64_t tcp_rack_scwnd;
219 uint64_t tcp_rack_noprr;
220 uint64_t tcp_rack_cfg_rate;
221 uint64_t tcp_timely_dyn;
222 uint64_t tcp_rack_mbufq;
226 uint64_t tcp_profile;
227 uint64_t tcp_hdwr_rate_cap;
228 uint64_t tcp_pacing_rate_cap;
229 uint64_t tcp_pacing_up_only;
230 uint64_t tcp_use_cmp_acks;
231 uint64_t tcp_rack_abc_val;
232 uint64_t tcp_rec_abc_val;
233 uint64_t tcp_rack_measure_cnt;
234 uint64_t tcp_rack_delayed_ack;
235 uint64_t tcp_rack_rtt_use;
236 uint64_t tcp_data_after_close;
237 uint64_t tcp_defer_opt;
238 uint64_t tcp_rxt_clamp;
239 uint64_t tcp_rack_beta;
240 uint64_t tcp_rack_beta_ecn;
241 uint64_t tcp_rack_timer_slop;
242 uint64_t tcp_rack_dsack_opt;
243 uint64_t tcp_rack_hi_beta;
244 uint64_t tcp_split_limit;
245 uint64_t tcp_rack_pacing_divisor;
246 uint64_t tcp_rack_min_seg;
247 uint64_t tcp_dgp_in_rec;
250 /* RTT shrink reasons */
251 #define RACK_RTTS_INIT 0
252 #define RACK_RTTS_NEWRTT 1
253 #define RACK_RTTS_EXITPROBE 2
254 #define RACK_RTTS_ENTERPROBE 3
255 #define RACK_RTTS_REACHTARGET 4
256 #define RACK_RTTS_SEEHBP 5
257 #define RACK_RTTS_NOBACKOFF 6
258 #define RACK_RTTS_SAFETY 7
260 #define RACK_USE_BEG 1
261 #define RACK_USE_END 2
262 #define RACK_USE_END_OR_THACK 3
264 #define TLP_USE_ID 1 /* Internet draft behavior */
265 #define TLP_USE_TWO_ONE 2 /* Use 2.1 behavior */
266 #define TLP_USE_TWO_TWO 3 /* Use 2.2 behavior */
267 #define RACK_MIN_BW 8000 /* 64kbps in Bps */
269 /* Rack quality indicators for GPUT measurements */
270 #define RACK_QUALITY_NONE 0 /* No quality stated */
271 #define RACK_QUALITY_HIGH 1 /* A normal measurement of a GP RTT */
272 #define RACK_QUALITY_APPLIMITED 2 /* An app limited case that may be of lower quality */
273 #define RACK_QUALITY_PERSIST 3 /* A measurement where we went into persists */
274 #define RACK_QUALITY_PROBERTT 4 /* A measurement where we went into or exited probe RTT */
275 #define RACK_QUALITY_ALLACKED 5 /* All data is now acknowledged */
277 #define MIN_GP_WIN 6 /* We need at least 6 MSS in a GP measurement */
279 #define RACK_OPTS_SIZE (sizeof(struct rack_opts_stats)/sizeof(uint64_t))
280 extern counter_u64_t rack_opts_arry[RACK_OPTS_SIZE];
281 #define RACK_OPTS_ADD(name, amm) counter_u64_add(rack_opts_arry[(offsetof(struct rack_opts_stats, name)/sizeof(uint64_t))], (amm))
282 #define RACK_OPTS_INC(name) RACK_OPTS_ADD(name, 1)
285 * As we get each SACK we wade through the
286 * rc_map and mark off what is acked.
287 * We also increment rc_sacked as well.
289 * We also pay attention to missing entries
290 * based on the time and possibly mark them
291 * for retransmit. If we do and we are not already
292 * in recovery we enter recovery. In doing
293 * so we claer prr_delivered/holes_rxt and prr_sent_dur_rec.
294 * We also setup rc_next/rc_snd_nxt/rc_send_end so
295 * we will know where to send from. When not in
296 * recovery rc_next will be NULL and rc_snd_nxt should
299 * Whenever we retransmit from recovery we increment
300 * rc_holes_rxt as we retran a block and mark it as retransmitted
301 * with the time it was sent. During non-recovery sending we
302 * add to our map and note the time down of any send expanding
303 * the rc_map at the tail and moving rc_snd_nxt up with snd_max.
305 * In recovery during SACK/ACK processing if a chunk has
306 * been retransmitted and it is now acked, we decrement rc_holes_rxt.
307 * When we retransmit from the scoreboard we use
308 * rc_next and rc_snd_nxt/rc_send_end to help us
309 * find what needs to be retran.
311 * To calculate pipe we simply take (snd_max - snd_una) + rc_holes_rxt
312 * This gets us the effect of RFC6675 pipe, counting twice for
313 * bytes retransmitted.
316 #define TT_RACK_FR_TMR 0x2000
319 * Locking for the rack control block.
320 * a) Locked by INP_WLOCK
321 * b) Locked by the hpts-mutex
324 #define RACK_GP_HIST 4 /* How much goodput history do we maintain? */
326 #define RACK_NUM_FSB_DEBUG 16
328 struct rack_fast_send_blk {
329 uint32_t left_to_send;
330 uint16_t tcp_ip_hdr_len;
341 uint32_t rfo_apply_push : 1,
348 struct rack_control {
349 /* Second cache line 0x40 from tcp_rack */
350 struct tailq_hash *tqh; /* Tree of all segments Lock(a) */
351 struct rack_head rc_tmap; /* List in transmit order Lock(a) */
352 struct rack_sendmap *rc_tlpsend; /* Remembered place for
353 * tlp_sending Lock(a) */
354 struct rack_sendmap *rc_resend; /* something we have been asked to
356 struct rack_fast_send_blk fsb; /* The fast-send block */
358 uint16_t pace_len_divisor;
359 uint16_t rc_user_set_min_segs;
360 uint32_t rc_hpts_flags;
361 uint32_t rc_fixed_pacing_rate_ca;
362 uint32_t rc_fixed_pacing_rate_rec;
363 uint32_t rc_fixed_pacing_rate_ss;
364 uint32_t cwnd_to_use; /* The cwnd in use */
365 uint32_t rc_timer_exp; /* If a timer ticks of expiry */
366 uint32_t rc_rack_min_rtt; /* lowest RTT seen Lock(a) */
367 uint32_t rc_rack_largest_cwnd; /* Largest CWND we have seen Lock(a) */
369 /* Third Cache line 0x80 */
370 struct rack_head rc_free; /* Allocation array */
371 uint64_t last_hw_bw_req;
372 uint64_t crte_prev_rate;
373 uint64_t bw_rate_cap;
374 uint64_t last_cumack_advance; /* Last time cumack moved forward */
375 uint32_t rc_reorder_ts; /* Last time we saw reordering Lock(a) */
377 uint32_t rc_tlp_new_data; /* we need to send new-data on a TLP
379 uint32_t rc_prr_out; /* bytes sent during recovery Lock(a) */
381 uint32_t rc_prr_recovery_fs; /* recovery fs point Lock(a) */
383 uint32_t rc_prr_sndcnt; /* Prr sndcnt Lock(a) */
385 uint32_t rc_sacked; /* Tot sacked on scoreboard Lock(a) */
386 uint32_t last_sent_tlp_seq; /* Last tlp sequence that was retransmitted Lock(a) */
388 uint32_t rc_prr_delivered; /* during recovery prr var Lock(a) */
390 uint16_t rc_tlp_cnt_out; /* count of times we have sent a TLP without new data */
391 uint16_t last_sent_tlp_len; /* Number of bytes in the last sent tlp */
393 uint32_t rc_loss_count; /* How many bytes have been retransmitted
395 uint32_t rc_reorder_fade; /* Socket option value Lock(a) */
397 /* Forth cache line 0xc0 */
400 uint32_t rc_rack_tmit_time; /* Rack transmit time Lock(a) */
401 uint32_t rc_holes_rxt; /* Tot retraned from scoreboard Lock(a) */
403 uint32_t rc_num_maps_alloced; /* Number of map blocks (sacks) we
405 uint32_t rc_rcvtime; /* When we last received data */
406 uint32_t rc_num_split_allocs; /* num split map entries allocated */
407 uint32_t rc_split_limit; /* Limit from control var can be set by socket opt */
409 uint32_t rc_last_output_to;
410 uint32_t rc_went_idle_time;
412 struct rack_sendmap *rc_sacklast; /* sack remembered place
415 struct rack_sendmap *rc_first_appl; /* Pointer to first app limited */
416 struct rack_sendmap *rc_end_appl; /* Pointer to last app limited */
417 /* Cache line split 0x100 */
418 struct sack_filter rack_sf;
419 /* Cache line split 0x140 */
420 /* Flags for various things */
421 uint32_t rc_pace_max_segs;
422 uint32_t rc_pace_min_segs;
423 uint32_t rc_app_limited_cnt;
424 uint16_t rack_per_of_gp_ss; /* 100 = 100%, so from 65536 = 655 x bw */
425 uint16_t rack_per_of_gp_ca; /* 100 = 100%, so from 65536 = 655 x bw */
426 uint16_t rack_per_of_gp_rec; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */
427 uint16_t rack_per_of_gp_probertt; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */
428 uint32_t rc_high_rwnd;
431 uint32_t sack_noextra_move;
432 uint32_t sack_moved_extra;
433 struct rack_rtt_sample rack_rs;
434 const struct tcp_hwrate_limit_table *crte;
435 uint32_t rc_agg_early;
436 uint32_t rc_agg_delayed;
437 uint32_t rc_tlp_rxt_last_time;
438 uint32_t rc_saved_cwnd;
439 uint64_t rc_gp_output_ts; /* chg*/
440 uint64_t rc_gp_cumack_ts; /* chg*/
441 struct timeval act_rcv_time;
442 struct timeval rc_last_time_decay; /* SAD time decay happened here */
445 #ifdef NETFLIX_SHARED_CWND
446 struct shared_cwnd *rc_scw;
448 uint64_t last_gp_comp_bw;
449 uint64_t last_max_bw; /* Our calculated max b/w last */
450 struct time_filter_small rc_gp_min_rtt;
451 struct def_opt_head opt_list;
452 uint64_t lt_bw_time; /* Total time with data outstanding (lt_bw = long term bandwidth) */
453 uint64_t lt_bw_bytes; /* Total bytes acked */
454 uint64_t lt_timemark; /* 64 bit timestamp when we started sending */
455 struct tcp_sendfile_track *rc_last_sft;
456 uint32_t lt_seq; /* Seq at start of lt_bw gauge */
457 int32_t rc_rtt_diff; /* Timely style rtt diff of our gp_srtt */
458 uint64_t last_sndbytes;
459 uint64_t last_snd_rxt_bytes;
460 uint64_t rxt_threshold;
461 uint64_t last_tmit_time_acked; /* Holds the last cumack point's last send time */
462 uint32_t last_rnd_rxt_clamped;
463 uint32_t num_of_clamps_applied;
464 uint32_t clamp_options;
467 uint32_t rc_gp_srtt; /* Current GP srtt */
468 uint32_t rc_prev_gp_srtt; /* Previous RTT */
469 uint32_t rc_entry_gp_rtt; /* Entry to PRTT gp-rtt */
470 uint32_t rc_loss_at_start; /* At measurement window where was our lost value */
472 uint32_t dsack_round_end; /* In a round of seeing a DSACK */
473 uint32_t current_round; /* Starting at zero */
474 uint32_t roundends; /* acked value above which round ends */
475 uint32_t num_dsack; /* Count of dsack's seen (1 per window)*/
476 uint32_t forced_ack_ts;
477 uint32_t last_collapse_point; /* Last point peer collapsed too */
478 uint32_t high_collapse_point;
479 uint32_t rc_lower_rtt_us_cts; /* Time our GP rtt was last lowered */
480 uint32_t rc_time_probertt_entered;
481 uint32_t rc_time_probertt_starts;
482 uint32_t rc_lowest_us_rtt;
483 uint32_t rc_highest_us_rtt;
484 uint32_t rc_last_us_rtt;
485 uint32_t rc_time_of_last_probertt;
486 uint32_t rc_target_probertt_flight;
487 uint32_t rc_probertt_sndmax_atexit; /* Highest sent to in probe-rtt */
488 uint32_t rc_cwnd_at_erec;
489 uint32_t rc_ssthresh_at_erec;
490 uint32_t dsack_byte_cnt;
491 uint32_t retran_during_recovery;
492 uint32_t rc_gp_lowrtt; /* Lowest rtt seen during GPUT measurement */
493 uint32_t rc_gp_high_rwnd; /* Highest rwnd seen during GPUT measurement */
494 uint32_t rc_snd_max_at_rto; /* For non-sack when the RTO occurred what was snd-max */
495 uint32_t rc_out_at_rto;
496 int32_t rc_scw_index;
497 uint32_t rc_tlp_threshold; /* Socket option value Lock(a) */
498 uint32_t rc_last_timeout_snduna;
499 uint32_t last_tlp_acked_start;
500 uint32_t last_tlp_acked_end;
501 uint32_t challenge_ack_ts;
502 uint32_t challenge_ack_cnt;
503 uint32_t rc_min_to; /* Socket option value Lock(a) */
504 uint32_t rc_pkt_delay; /* Socket option value Lock(a) */
505 uint32_t persist_lost_ends;
506 uint32_t ack_during_sd;
508 uint32_t saved_input_pkt;
509 uint32_t saved_rxt_clamp_val; /* The encoded value we used to setup clamping */
510 struct newreno rc_saved_beta; /*
512 * rc_saved_cc are the values we have had
513 * set by the user, if pacing is not happening
514 * (i.e. its early and we have not turned on yet
515 * or it was turned off). The minute pacing
516 * is turned on we pull out the values currently
517 * being used by newreno and replace them with
518 * these values, then save off the old values here,
519 * we also set the flag (if ecn_beta is set) to make
520 * new_reno do less of a backoff for ecn (think abe).
522 uint16_t rc_early_recovery_segs; /* Socket option value Lock(a) */
523 uint16_t rc_reorder_shift; /* Socket option value Lock(a) */
524 uint8_t rack_per_upper_bound_ss;
525 uint8_t rack_per_upper_bound_ca;
526 uint8_t dsack_persist;
527 uint8_t rc_no_push_at_mrtt; /* No push when we exceed max rtt */
528 uint8_t num_measurements; /* Number of measurements (up to 0xff, we freeze at 0xff) */
529 uint8_t req_measurements; /* How many measurements are required? */
530 uint8_t saved_hibeta;
531 uint8_t rc_tlp_cwnd_reduce; /* Socket option value Lock(a) */
532 uint8_t rc_prr_sendalot;/* Socket option value Lock(a) */
533 uint8_t rc_rate_sample_method;
534 uint8_t rc_dgp_bl_agg; /* Buffer Level aggression during DGP */
535 uint8_t full_dgp_in_rec; /* Flag to say if we do full DGP in recovery */
536 uint8_t client_suggested_maxseg; /* Not sure what to do with this yet */
537 uint8_t pacing_discount_amm; /*
538 * This is a multipler to the base discount that
539 * can be used to increase the discount.
541 uint8_t already_had_a_excess;
545 /* DGP with no buffer level mitigations */
549 * DGP with buffer level mitigation where BL:4 caps fillcw and BL:5
555 * DGP with buffer level mitigation where BL:3 caps fillcw and BL:4 turns off fillcw
556 * and BL:5 reduces by 10%
561 * DGP with buffer level mitigation where BL:2 caps fillcw and BL:3 turns off
562 * fillcw BL:4 reduces by 10% and BL:5 reduces by 20%
566 /* Hybrid pacing log defines */
567 #define HYBRID_LOG_NO_ROOM 0 /* No room for the clients request */
568 #define HYBRID_LOG_TURNED_OFF 1 /* Turned off hybrid pacing */
569 #define HYBRID_LOG_NO_PACING 2 /* Failed to set pacing on */
570 #define HYBRID_LOG_RULES_SET 3 /* Hybrid pacing for this chunk is set */
571 #define HYBRID_LOG_NO_RANGE 4 /* In DGP mode, no range found */
572 #define HYBRID_LOG_RULES_APP 5 /* The specified rules were applied */
573 #define HYBRID_LOG_REQ_COMP 6 /* The request completed */
574 #define HYBRID_LOG_BW_MEASURE 7 /* Follow up b/w measurements to the previous completed log */
575 #define HYBRID_LOG_RATE_CAP 8 /* We had a rate cap apply */
576 #define HYBRID_LOG_CAP_CALC 9 /* How we calculate the cap */
577 #define HYBRID_LOG_ISSAME 10 /* Same as before -- temp */
578 #define HYBRID_LOG_ALLSENT 11 /* We sent it all no more rate-cap */
579 #define HYBRID_LOG_OUTOFTIME 12 /* We are past the deadline DGP */
580 #define HYBRID_LOG_CAPERROR 13 /* Hit one of the TSNH cases */
581 #define HYBRID_LOG_EXTEND 14 /* We extended the end */
582 #define HYBRID_LOG_SENT_LOST 15 /* A closing sent/lost report */
584 #define RACK_TIMELY_CNT_BOOST 5 /* At 5th increase boost */
585 #define RACK_MINRTT_FILTER_TIM 10 /* Seconds */
587 #define RACK_HYSTART_OFF 0
588 #define RACK_HYSTART_ON 1 /* hystart++ on */
589 #define RACK_HYSTART_ON_W_SC 2 /* hystart++ on +Slam Cwnd */
590 #define RACK_HYSTART_ON_W_SC_C 3 /* hystart++ on,
591 * Conservative ssthresh and
595 #define MAX_USER_SET_SEG 0x3f /* The max we can set is 63 which is probably too many */
600 /* First cache line 0x00 */
601 TAILQ_ENTRY(tcp_rack) r_hpts; /* hptsi queue next Lock(b) */
602 int32_t(*r_substate) (struct mbuf *, struct tcphdr *,
603 struct socket *, struct tcpcb *, struct tcpopt *,
604 int32_t, int32_t, uint32_t, int, int, uint8_t); /* Lock(a) */
605 struct tcpcb *rc_tp; /* The tcpcb Lock(a) */
606 struct inpcb *rc_inp; /* The inpcb Lock(a) */
607 uint8_t rc_free_cnt; /* Number of free entries on the rc_free list
609 uint8_t client_bufferlvl : 3, /* Expected range [0,5]: 0=unset, 1=low/empty */
610 rack_deferred_inited : 1,
611 /* ******************************************************************** */
612 /* Note for details of next two fields see rack_init_retransmit_rate() */
613 /* ******************************************************************** */
615 shape_rxt_to_pacing_min : 1,
616 /* ******************************************************************** */
618 r_pacing_discount : 1;
619 uint8_t no_prr_addback : 1,
622 excess_rxt_on: 1, /* Are actions on for excess retransmissions? */
623 rc_ack_can_sendout_data: 1, /*
624 * If set it will override pacing restrictions on not sending
625 * data when the pacing timer is running. I.e. you set this
626 * and an ACK will send data. Default is off and its only used
627 * without pacing when we are doing 5G speed up for there
630 rc_pacing_cc_set: 1, /*
631 * If we are pacing (pace_always=1) and we have reached the
632 * point where we start pacing (fixed or gp has reached its
633 * magic gp_ready state) this flag indicates we have set in
634 * values to effect CC's backoff's. If pacing is turned off
635 * then we must restore the values saved in rc_saved_beta,
636 * if its going to gp_ready we need to copy the values into
637 * the CC module and set our flags.
639 * Note this only happens if the cc name is newreno (CCALGONAME_NEWRENO).
642 rc_rack_tmr_std_based :1,
643 rc_rack_use_dsack: 1;
644 uint8_t rc_dsack_round_seen: 1,
645 rc_last_tlp_acked_set: 1,
646 rc_last_tlp_past_cumack: 1,
647 rc_last_sent_tlp_seq_valid: 1,
648 rc_last_sent_tlp_past_cumack: 1,
649 probe_not_answered: 1,
652 uint32_t rc_rack_rtt; /* RACK-RTT Lock(a) */
653 uint16_t r_mbuf_queue : 1, /* Do we do mbuf queue for non-paced */
654 rtt_limit_mul : 4, /* muliply this by low rtt */
656 r_must_retran : 1, /* For non-sack customers we hit an RTO and new data should be resends */
657 r_use_cmp_ack: 1, /* Do we use compressed acks */
658 r_ent_rec_ns: 1, /* We entered recovery and have not sent */
659 r_might_revert: 1, /* Flag to find out if we might need to revert */
660 r_fast_output: 1, /* Fast output is in progress we can skip the bulk of rack_output */
662 r_rack_hw_rate_caps: 1,
667 uint8_t rc_user_set_max_segs : 7, /* Socket option value Lock(a) */
668 rc_fillcw_apply_discount;
669 uint8_t rc_labc; /* Appropriate Byte Counting Value */
670 uint16_t forced_ack : 1,
673 rc_gp_timely_inc_cnt : 3,
674 rc_gp_timely_dec_cnt : 3,
675 r_use_labc_for_rec: 1,
676 rc_highly_buffered: 1, /* The path is highly buffered */
677 rc_dragged_bottom: 1,
678 rc_pace_dnd : 1, /* The pace do not disturb bit */
682 uint8_t r_state : 4, /* Current rack state Lock(a) */
683 rc_catch_up : 1, /* catch up mode in dgp */
684 rc_hybrid_mode : 1, /* We are in hybrid mode */
685 rc_suspicious : 1, /* Suspect sacks have been given */
686 rc_new_rnd_needed: 1;
687 uint8_t rc_tmr_stopped : 7,
688 t_timers_stopped : 1;
689 uint8_t rc_enobuf : 7, /* count of enobufs on connection provides */
691 uint8_t r_timer_override : 1, /* hpts override Lock(a) */
692 r_is_v6 : 1, /* V6 pcb Lock(a) */
694 rc_tlp_in_progress : 1,
695 rc_always_pace : 1, /* Socket option value Lock(a) */
697 rc_pace_fill_if_rttin_range : 1,
698 rc_srtt_measure_made : 1;
699 uint8_t app_limited_needs_set : 1,
701 rc_has_collapsed : 1,
702 r_cwnd_was_clamped : 1,
703 r_clamped_gets_lower : 1,
704 rack_hdrw_pacing : 1, /* We are doing Hardware pacing */
705 rack_hdw_pace_ena : 1, /* Is hardware pacing enabled? */
706 rack_attempt_hdwr_pace : 1; /* Did we attempt hdwr pacing (if allowed) */
707 uint8_t rack_tlp_threshold_use : 3, /* only 1, 2 and 3 used so far */
708 rack_rec_nonrxt_use_cr : 1,
709 rack_enable_scwnd : 1,
710 rack_attempted_scwnd : 1,
712 rack_scwnd_is_idle : 1;
713 uint8_t rc_allow_data_af_clo: 1,
715 set_pacing_done_a_iw : 1,
717 alloc_limit_reported : 1,
718 sack_attack_disable : 1,
720 rc_force_max_seg : 1;
725 r_persist_lt_bw_off : 1,
726 r_collapse_point_valid : 1,
728 uint16_t rc_init_win : 8,
734 rc_gp_no_rec_chg : 1,
736 measure_saw_probe_rtt : 1;
737 /* Cache line 2 0x40 */
738 struct rack_control r_ctl;
739 } __aligned(CACHE_LINE_SIZE);