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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 occured 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_NUM_OF_RETRANS 3
50 #define RACK_INITIAL_RTO 1000000 /* 1 second in microseconds */
52 #define RACK_REQ_AVG 3 /* Must be less than 256 */
55 TAILQ_ENTRY(rack_sendmap) r_tnext; /* Time of transmit based next */
56 uint32_t r_start; /* Sequence number of the segment */
57 uint32_t r_end; /* End seq, this is 1 beyond actually */
58 uint32_t r_rtr_bytes; /* How many bytes have been retransmitted */
59 uint32_t r_flags : 24, /* Flags as defined above */
60 r_rtr_cnt : 8; /* Retran count, index this -1 to get time */
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 */
76 uint32_t r_fas; /* Flight at send */
79 struct deferred_opt_list {
80 TAILQ_ENTRY(deferred_opt_list) next;
86 * Timestamps in the rack sendmap are now moving to be
87 * uint64_t's. This means that if you want a uint32_t
88 * usec timestamp (the old usecond timestamp) you simply have
89 * to cast it to uint32_t. The reason we do this is not for
90 * wrap, but we need to get back, at times, to the millisecond
91 * timestamp that is used in the TSTMP option. To do this we
92 * can use the rack_ts_to_msec() inline below which can take
93 * the 64bit ts and make into the correct timestamp millisecond
94 * wise. Thats not possible with the 32bit usecond timestamp since
95 * the seconds wrap too quickly to cover all bases.
97 * There are quite a few places in rack where I simply cast
98 * back to uint32_t and then end up using the TSTMP_XX()
99 * macros. This is ok, but we could do simple compares if
100 * we ever decided to move all of those variables to 64 bits
105 rack_to_usec_ts(struct timeval *tv)
107 return ((tv->tv_sec * HPTS_USEC_IN_SEC) + tv->tv_usec);
111 rack_ts_to_msec(uint64_t ts)
113 return((uint32_t)(ts / HPTS_MSEC_IN_SEC));
117 RB_HEAD(rack_rb_tree_head, rack_sendmap);
118 TAILQ_HEAD(rack_head, rack_sendmap);
119 TAILQ_HEAD(def_opt_head, deferred_opt_list);
121 /* Map change logging */
122 #define MAP_MERGE 0x01
123 #define MAP_SPLIT 0x02
125 #define MAP_SACK_M1 0x04
126 #define MAP_SACK_M2 0x05
127 #define MAP_SACK_M3 0x06
128 #define MAP_SACK_M4 0x07
129 #define MAP_SACK_M5 0x08
130 #define MAP_FREE 0x09
131 #define MAP_TRIM_HEAD 0x0a
133 #define RACK_LIMIT_TYPE_SPLIT 1
136 * We use the rate sample structure to
137 * assist in single sack/ack rate and rtt
138 * calculation. In the future we will expand
139 * this in BBR to do forward rate sample
142 #define RACK_RTT_EMPTY 0x00000001 /* Nothing yet stored in RTT's */
143 #define RACK_RTT_VALID 0x00000002 /* We have at least one valid RTT */
144 struct rack_rtt_sample {
146 uint32_t rs_rtt_lowest;
147 uint32_t rs_rtt_highest;
152 uint16_t rs_us_rtrcnt;
155 #define RACK_LOG_TYPE_ACK 0x01
156 #define RACK_LOG_TYPE_OUT 0x02
157 #define RACK_LOG_TYPE_TO 0x03
158 #define RACK_LOG_TYPE_ALLOC 0x04
159 #define RACK_LOG_TYPE_FREE 0x05
162 * Magic numbers for logging timeout events if the
163 * logging is enabled.
165 #define RACK_TO_FRM_TMR 1
166 #define RACK_TO_FRM_TLP 2
167 #define RACK_TO_FRM_RACK 3
168 #define RACK_TO_FRM_KEEP 4
169 #define RACK_TO_FRM_PERSIST 5
170 #define RACK_TO_FRM_DELACK 6
172 struct rack_opts_stats {
173 uint64_t tcp_rack_tlp_reduce;
174 uint64_t tcp_rack_pace_always;
175 uint64_t tcp_rack_pace_reduce;
176 uint64_t tcp_rack_max_seg;
177 uint64_t tcp_rack_prr_sendalot;
178 uint64_t tcp_rack_min_to;
179 uint64_t tcp_rack_early_seg;
180 uint64_t tcp_rack_reord_thresh;
181 uint64_t tcp_rack_reord_fade;
182 uint64_t tcp_rack_tlp_thresh;
183 uint64_t tcp_rack_pkt_delay;
184 uint64_t tcp_rack_tlp_inc_var;
185 uint64_t tcp_tlp_use;
186 uint64_t tcp_rack_idle_reduce;
187 uint64_t tcp_rack_idle_reduce_high;
188 uint64_t rack_no_timer_in_hpts;
189 uint64_t tcp_rack_min_pace_seg;
190 uint64_t tcp_rack_pace_rate_ca;
191 uint64_t tcp_rack_rr;
192 uint64_t tcp_rack_do_detection;
193 uint64_t tcp_rack_rrr_no_conf_rate;
194 uint64_t tcp_initial_rate;
195 uint64_t tcp_initial_win;
196 uint64_t tcp_hdwr_pacing;
197 uint64_t tcp_gp_inc_ss;
198 uint64_t tcp_gp_inc_ca;
199 uint64_t tcp_gp_inc_rec;
200 uint64_t tcp_rack_force_max_seg;
201 uint64_t tcp_rack_pace_rate_ss;
202 uint64_t tcp_rack_pace_rate_rec;
203 /* Temp counters for dsack */
204 uint64_t tcp_sack_path_1;
205 uint64_t tcp_sack_path_2a;
206 uint64_t tcp_sack_path_2b;
207 uint64_t tcp_sack_path_3;
208 uint64_t tcp_sack_path_4;
209 /* non temp counters */
210 uint64_t tcp_rack_scwnd;
211 uint64_t tcp_rack_noprr;
212 uint64_t tcp_rack_cfg_rate;
213 uint64_t tcp_timely_dyn;
214 uint64_t tcp_rack_mbufq;
218 uint64_t tcp_profile;
219 uint64_t tcp_hdwr_rate_cap;
220 uint64_t tcp_pacing_rate_cap;
221 uint64_t tcp_pacing_up_only;
222 uint64_t tcp_use_cmp_acks;
223 uint64_t tcp_rack_abc_val;
224 uint64_t tcp_rec_abc_val;
225 uint64_t tcp_rack_measure_cnt;
226 uint64_t tcp_rack_delayed_ack;
227 uint64_t tcp_rack_rtt_use;
228 uint64_t tcp_data_after_close;
229 uint64_t tcp_defer_opt;
230 uint64_t tcp_rack_fastrsm_hack;
231 uint64_t tcp_rack_beta;
232 uint64_t tcp_rack_beta_ecn;
233 uint64_t tcp_rack_timer_slop;
234 uint64_t tcp_rack_dsack_opt;
237 /* RTT shrink reasons */
238 #define RACK_RTTS_INIT 0
239 #define RACK_RTTS_NEWRTT 1
240 #define RACK_RTTS_EXITPROBE 2
241 #define RACK_RTTS_ENTERPROBE 3
242 #define RACK_RTTS_REACHTARGET 4
243 #define RACK_RTTS_SEEHBP 5
244 #define RACK_RTTS_NOBACKOFF 6
245 #define RACK_RTTS_SAFETY 7
247 #define RACK_USE_BEG 1
248 #define RACK_USE_END 2
249 #define RACK_USE_END_OR_THACK 3
251 #define TLP_USE_ID 1 /* Internet draft behavior */
252 #define TLP_USE_TWO_ONE 2 /* Use 2.1 behavior */
253 #define TLP_USE_TWO_TWO 3 /* Use 2.2 behavior */
254 #define RACK_MIN_BW 8000 /* 64kbps in Bps */
256 /* Rack quality indicators for GPUT measurements */
257 #define RACK_QUALITY_NONE 0 /* No quality stated */
258 #define RACK_QUALITY_HIGH 1 /* A normal measurement of a GP RTT */
259 #define RACK_QUALITY_APPLIMITED 2 /* An app limited case that may be of lower quality */
260 #define RACK_QUALITY_PERSIST 3 /* A measurement where we went into persists */
261 #define RACK_QUALITY_PROBERTT 4 /* A measurement where we went into or exited probe RTT */
262 #define RACK_QUALITY_ALLACKED 5 /* All data is now acknowledged */
264 /*********************/
265 /* Rack Trace points */
266 /*********************/
268 * Rack trace points are interesting points within
269 * the rack code that the author/debugger may want
270 * to have BB logging enabled if we hit that point.
271 * In order to enable a trace point you set the
272 * sysctl var net.inet.tcp.<stack>.tp.number to
273 * one of the numbers listed below. You also
274 * must make sure net.inet.tcp.<stack>.tp.bbmode is
275 * non-zero, the default is 4 for continuous tracing.
276 * You also set in the number of connections you want
277 * have get BB logs in net.inet.tcp.<stack>.tp.count.
279 * Count will decrement every time BB logging is assigned
280 * to a connection that hit your tracepoint.
282 * You can enable all trace points by setting the number
283 * to 0xffffffff. You can disable all trace points by
284 * setting number to zero (or count to 0).
286 * Below are the enumerated list of tracepoints that
287 * have currently been defined in the code. Add more
288 * as you add a call to rack_trace_point(rack, <name>);
289 * where <name> is defined below.
291 #define RACK_TP_HWENOBUF 0x00000001 /* When we are doing hardware pacing and hit enobufs */
292 #define RACK_TP_ENOBUF 0x00000002 /* When we hit enobufs with software pacing */
293 #define RACK_TP_COLLAPSED_WND 0x00000003 /* When a peer to collapses its rwnd on us */
294 #define RACK_TP_COLLAPSED_RXT 0x00000004 /* When we actually retransmit a collapsed window rsm */
296 #define MIN_GP_WIN 6 /* We need at least 6 MSS in a GP measurement */
298 #define RACK_OPTS_SIZE (sizeof(struct rack_opts_stats)/sizeof(uint64_t))
299 extern counter_u64_t rack_opts_arry[RACK_OPTS_SIZE];
300 #define RACK_OPTS_ADD(name, amm) counter_u64_add(rack_opts_arry[(offsetof(struct rack_opts_stats, name)/sizeof(uint64_t))], (amm))
301 #define RACK_OPTS_INC(name) RACK_OPTS_ADD(name, 1)
304 * As we get each SACK we wade through the
305 * rc_map and mark off what is acked.
306 * We also increment rc_sacked as well.
308 * We also pay attention to missing entries
309 * based on the time and possibly mark them
310 * for retransmit. If we do and we are not already
311 * in recovery we enter recovery. In doing
312 * so we claer prr_delivered/holes_rxt and prr_sent_dur_rec.
313 * We also setup rc_next/rc_snd_nxt/rc_send_end so
314 * we will know where to send from. When not in
315 * recovery rc_next will be NULL and rc_snd_nxt should
318 * Whenever we retransmit from recovery we increment
319 * rc_holes_rxt as we retran a block and mark it as retransmitted
320 * with the time it was sent. During non-recovery sending we
321 * add to our map and note the time down of any send expanding
322 * the rc_map at the tail and moving rc_snd_nxt up with snd_max.
324 * In recovery during SACK/ACK processing if a chunk has
325 * been retransmitted and it is now acked, we decrement rc_holes_rxt.
326 * When we retransmit from the scoreboard we use
327 * rc_next and rc_snd_nxt/rc_send_end to help us
328 * find what needs to be retran.
330 * To calculate pipe we simply take (snd_max - snd_una) + rc_holes_rxt
331 * This gets us the effect of RFC6675 pipe, counting twice for
332 * bytes retransmitted.
335 #define TT_RACK_FR_TMR 0x2000
338 * Locking for the rack control block.
339 * a) Locked by INP_WLOCK
340 * b) Locked by the hpts-mutex
343 #define RACK_GP_HIST 4 /* How much goodput history do we maintain? */
345 #define RACK_NUM_FSB_DEBUG 16
347 struct rack_fast_send_blk {
348 uint32_t left_to_send;
349 uint16_t tcp_ip_hdr_len;
359 uint32_t rfo_apply_push : 1,
364 struct rack_control {
365 /* Second cache line 0x40 from tcp_rack */
366 struct rack_rb_tree_head rc_mtree; /* Tree of all segments Lock(a) */
367 struct rack_head rc_tmap; /* List in transmit order Lock(a) */
368 struct rack_sendmap *rc_tlpsend; /* Remembered place for
369 * tlp_sending Lock(a) */
370 struct rack_sendmap *rc_resend; /* something we have been asked to
372 struct rack_fast_send_blk fsb; /* The fast-send block */
375 uint32_t saved_input_pkt;
376 uint32_t rc_hpts_flags;
377 uint32_t rc_fixed_pacing_rate_ca;
378 uint32_t rc_fixed_pacing_rate_rec;
379 uint32_t rc_fixed_pacing_rate_ss;
380 uint32_t cwnd_to_use; /* The cwnd in use */
381 uint32_t rc_timer_exp; /* If a timer ticks of expiry */
382 uint32_t rc_rack_min_rtt; /* lowest RTT seen Lock(a) */
383 uint32_t rc_rack_largest_cwnd; /* Largest CWND we have seen Lock(a) */
385 /* Third Cache line 0x80 */
386 struct rack_head rc_free; /* Allocation array */
387 uint64_t last_hw_bw_req;
388 uint64_t crte_prev_rate;
389 uint64_t bw_rate_cap;
390 uint32_t rc_reorder_ts; /* Last time we saw reordering Lock(a) */
392 uint32_t rc_tlp_new_data; /* we need to send new-data on a TLP
394 uint32_t rc_prr_out; /* bytes sent during recovery Lock(a) */
396 uint32_t rc_prr_recovery_fs; /* recovery fs point Lock(a) */
398 uint32_t rc_prr_sndcnt; /* Prr sndcnt Lock(a) */
400 uint32_t rc_sacked; /* Tot sacked on scoreboard Lock(a) */
401 uint32_t last_sent_tlp_seq; /* Last tlp sequence that was retransmitted Lock(a) */
403 uint32_t rc_prr_delivered; /* during recovery prr var Lock(a) */
404 uint16_t rc_tlp_cnt_out; /* count of times we have sent a TLP without new data */
405 uint16_t last_sent_tlp_len; /* Number of bytes in the last sent tlp */
407 uint32_t rc_loss_count; /* How many bytes have been retransmitted
409 uint32_t rc_reorder_fade; /* Socket option value Lock(a) */
411 /* Forth cache line 0xc0 */
414 uint32_t rc_rack_tmit_time; /* Rack transmit time Lock(a) */
415 uint32_t rc_holes_rxt; /* Tot retraned from scoreboard Lock(a) */
417 uint32_t rc_num_maps_alloced; /* Number of map blocks (sacks) we
419 uint32_t rc_rcvtime; /* When we last received data */
420 uint32_t rc_num_split_allocs; /* num split map entries allocated */
422 uint32_t rc_last_output_to;
423 uint32_t rc_went_idle_time;
425 struct rack_sendmap *rc_sacklast; /* sack remembered place
428 struct rack_sendmap *rc_first_appl; /* Pointer to first app limited */
429 struct rack_sendmap *rc_end_appl; /* Pointer to last app limited */
430 /* Cache line split 0x100 */
431 struct sack_filter rack_sf;
432 /* Cache line split 0x140 */
433 /* Flags for various things */
434 uint32_t rc_pace_max_segs;
435 uint32_t rc_pace_min_segs;
436 uint32_t rc_app_limited_cnt;
437 uint16_t rack_per_of_gp_ss; /* 100 = 100%, so from 65536 = 655 x bw */
438 uint16_t rack_per_of_gp_ca; /* 100 = 100%, so from 65536 = 655 x bw */
439 uint16_t rack_per_of_gp_rec; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */
440 uint16_t rack_per_of_gp_probertt; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */
441 uint32_t rc_high_rwnd;
444 uint32_t sack_noextra_move;
445 uint32_t sack_moved_extra;
446 struct rack_rtt_sample rack_rs;
447 const struct tcp_hwrate_limit_table *crte;
448 uint32_t rc_agg_early;
449 uint32_t rc_agg_delayed;
450 uint32_t rc_tlp_rxt_last_time;
451 uint32_t rc_saved_cwnd;
452 uint64_t rc_gp_output_ts; /* chg*/
453 uint64_t rc_gp_cumack_ts; /* chg*/
454 struct timeval act_rcv_time;
455 struct timeval rc_last_time_decay; /* SAD time decay happened here */
458 #ifdef NETFLIX_SHARED_CWND
459 struct shared_cwnd *rc_scw;
461 uint64_t last_gp_comp_bw;
462 uint64_t last_max_bw; /* Our calculated max b/w last */
463 struct time_filter_small rc_gp_min_rtt;
464 struct def_opt_head opt_list;
465 int32_t rc_rtt_diff; /* Timely style rtt diff of our gp_srtt */
466 uint32_t rc_gp_srtt; /* Current GP srtt */
467 uint32_t rc_prev_gp_srtt; /* Previous RTT */
468 uint32_t rc_entry_gp_rtt; /* Entry to PRTT gp-rtt */
469 uint32_t rc_loss_at_start; /* At measurement window where was our lost value */
471 uint32_t dsack_round_end; /* In a round of seeing a DSACK */
472 uint32_t current_round; /* Starting at zero */
473 uint32_t roundends; /* acked value above which round ends */
474 uint32_t num_dsack; /* Count of dsack's seen (1 per window)*/
475 uint32_t forced_ack_ts;
476 uint32_t last_collapse_point; /* Last point peer collapsed too */
477 uint32_t high_collapse_point;
478 uint32_t rc_lower_rtt_us_cts; /* Time our GP rtt was last lowered */
479 uint32_t rc_time_probertt_entered;
480 uint32_t rc_time_probertt_starts;
481 uint32_t rc_lowest_us_rtt;
482 uint32_t rc_highest_us_rtt;
483 uint32_t rc_last_us_rtt;
484 uint32_t rc_time_of_last_probertt;
485 uint32_t rc_target_probertt_flight;
486 uint32_t rc_probertt_sndmax_atexit; /* Highest sent to in probe-rtt */
487 uint32_t rc_cwnd_at_erec;
488 uint32_t rc_ssthresh_at_erec;
489 uint32_t dsack_byte_cnt;
490 uint32_t retran_during_recovery;
491 uint32_t rc_gp_lowrtt; /* Lowest rtt seen during GPUT measurement */
492 uint32_t rc_gp_high_rwnd; /* Highest rwnd seen during GPUT measurement */
493 uint32_t rc_snd_max_at_rto; /* For non-sack when the RTO occured what was snd-max */
494 uint32_t rc_out_at_rto;
495 int32_t rc_scw_index;
496 uint32_t rc_tlp_threshold; /* Socket option value Lock(a) */
497 uint32_t rc_last_timeout_snduna;
498 uint32_t last_tlp_acked_start;
499 uint32_t last_tlp_acked_end;
500 uint32_t challenge_ack_ts;
501 uint32_t challenge_ack_cnt;
502 uint32_t rc_min_to; /* Socket option value Lock(a) */
503 uint32_t rc_pkt_delay; /* Socket option value Lock(a) */
504 uint32_t persist_lost_ends;
505 struct newreno rc_saved_beta; /*
507 * rc_saved_cc are the values we have had
508 * set by the user, if pacing is not happening
509 * (i.e. its early and we have not turned on yet
510 * or it was turned off). The minute pacing
511 * is turned on we pull out the values currently
512 * being used by newreno and replace them with
513 * these values, then save off the old values here,
514 * we also set the flag (if ecn_beta is set) to make
515 * new_reno do less of a backoff for ecn (think abe).
517 uint16_t rc_early_recovery_segs; /* Socket option value Lock(a) */
518 uint16_t rc_reorder_shift; /* Socket option value Lock(a) */
519 uint8_t dsack_persist;
520 uint8_t rc_no_push_at_mrtt; /* No push when we exceed max rtt */
521 uint8_t num_measurements; /* Number of measurements (up to 0xff, we freeze at 0xff) */
522 uint8_t req_measurements; /* How many measurements are required? */
523 uint8_t rc_tlp_cwnd_reduce; /* Socket option value Lock(a) */
524 uint8_t rc_prr_sendalot;/* Socket option value Lock(a) */
525 uint8_t rc_rate_sample_method;
529 #define RACK_TIMELY_CNT_BOOST 5 /* At 5th increase boost */
530 #define RACK_MINRTT_FILTER_TIM 10 /* Seconds */
532 #define RACK_HYSTART_OFF 0
533 #define RACK_HYSTART_ON 1 /* hystart++ on */
534 #define RACK_HYSTART_ON_W_SC 2 /* hystart++ on +Slam Cwnd */
535 #define RACK_HYSTART_ON_W_SC_C 3 /* hystart++ on,
536 * Conservative ssthresh and
543 /* First cache line 0x00 */
544 TAILQ_ENTRY(tcp_rack) r_hpts; /* hptsi queue next Lock(b) */
545 int32_t(*r_substate) (struct mbuf *, struct tcphdr *,
546 struct socket *, struct tcpcb *, struct tcpopt *,
547 int32_t, int32_t, uint32_t, int, int, uint8_t); /* Lock(a) */
548 struct tcpcb *rc_tp; /* The tcpcb Lock(a) */
549 struct inpcb *rc_inp; /* The inpcb Lock(a) */
550 uint8_t rc_free_cnt; /* Number of free entries on the rc_free list
552 uint8_t client_bufferlvl : 4, /* Expected range [0,5]: 0=unset, 1=low/empty */
553 rack_deferred_inited : 1,
554 /* ******************************************************************** */
555 /* Note for details of next two fields see rack_init_retransmit_rate() */
556 /* ******************************************************************** */
558 shape_rxt_to_pacing_min : 1,
559 /* ******************************************************************** */
561 uint8_t no_prr_addback : 1,
565 rc_ack_can_sendout_data: 1, /*
566 * If set it will override pacing restrictions on not sending
567 * data when the pacing timer is running. I.e. you set this
568 * and an ACK will send data. Default is off and its only used
569 * without pacing when we are doing 5G speed up for there
572 rc_pacing_cc_set: 1, /*
573 * If we are pacing (pace_always=1) and we have reached the
574 * point where we start pacing (fixed or gp has reached its
575 * magic gp_ready state) this flag indicates we have set in
576 * values to effect CC's backoff's. If pacing is turned off
577 * then we must restore the values saved in rc_saved_beta,
578 * if its going to gp_ready we need to copy the values into
579 * the CC module and set our flags.
581 * Note this only happens if the cc name is newreno (CCALGONAME_NEWRENO).
584 rc_rack_tmr_std_based :1,
585 rc_rack_use_dsack: 1;
586 uint8_t rc_dsack_round_seen: 1,
587 rc_last_tlp_acked_set: 1,
588 rc_last_tlp_past_cumack: 1,
589 rc_last_sent_tlp_seq_valid: 1,
590 rc_last_sent_tlp_past_cumack: 1,
591 probe_not_answered: 1,
593 uint32_t rc_rack_rtt; /* RACK-RTT Lock(a) */
594 uint16_t r_mbuf_queue : 1, /* Do we do mbuf queue for non-paced */
595 rtt_limit_mul : 4, /* muliply this by low rtt */
597 r_must_retran : 1, /* For non-sack customers we hit an RTO and new data should be resends */
598 r_use_cmp_ack: 1, /* Do we use compressed acks */
599 r_ent_rec_ns: 1, /* We entered recovery and have not sent */
600 r_might_revert: 1, /* Flag to find out if we might need to revert */
601 r_fast_output: 1, /* Fast output is in progress we can skip the bulk of rack_output */
603 r_rack_hw_rate_caps: 1,
608 uint8_t rc_user_set_max_segs; /* Socket option value Lock(a) */
609 uint8_t rc_labc; /* Appropriate Byte Counting Value */
610 uint16_t forced_ack : 1,
613 rc_gp_timely_inc_cnt : 3,
614 rc_gp_timely_dec_cnt : 3,
615 r_use_labc_for_rec: 1,
616 rc_highly_buffered: 1, /* The path is highly buffered */
617 rc_dragged_bottom: 1,
618 rc_dack_mode : 1, /* Mac O/S emulation of d-ack */
619 rc_dack_toggle : 1, /* For Mac O/S emulation of d-ack */
622 uint8_t r_state; /* Current rack state Lock(a) */
623 uint8_t rc_tmr_stopped : 7,
624 t_timers_stopped : 1;
625 uint8_t rc_enobuf : 7, /* count of enobufs on connection provides */
627 uint8_t r_timer_override : 1, /* hpts override Lock(a) */
628 r_is_v6 : 1, /* V6 pcb Lock(a) */
630 rc_tlp_in_progress : 1,
631 rc_always_pace : 1, /* Socket option value Lock(a) */
633 rc_pace_fill_if_rttin_range : 1,
634 rc_srtt_measure_made : 1;
635 uint8_t app_limited_needs_set : 1,
637 rc_has_collapsed : 1,
640 rack_hdrw_pacing : 1, /* We are doing Hardware pacing */
641 rack_hdw_pace_ena : 1, /* Is hardware pacing enabled? */
642 rack_attempt_hdwr_pace : 1; /* Did we attempt hdwr pacing (if allowed) */
643 uint8_t rack_tlp_threshold_use : 3, /* only 1, 2 and 3 used so far */
644 rack_rec_nonrxt_use_cr : 1,
645 rack_enable_scwnd : 1,
646 rack_attempted_scwnd : 1,
648 rack_scwnd_is_idle : 1;
649 uint8_t rc_allow_data_af_clo: 1,
651 set_pacing_done_a_iw : 1,
653 alloc_limit_reported : 1,
654 sack_attack_disable : 1,
656 rc_force_max_seg : 1;
661 r_persist_lt_bw_off : 1,
662 r_collapse_point_valid : 1,
664 uint16_t rc_init_win : 8,
670 rc_gp_no_rec_chg : 1,
672 measure_saw_probe_rtt : 1;
673 /* Cache line 2 0x40 */
674 struct rack_control r_ctl;
675 } __aligned(CACHE_LINE_SIZE);