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
26 #ifndef _NETINET_TCP_RACK_H_
27 #define _NETINET_TCP_RACK_H_
28
29 #define RACK_ACKED 0x000001/* The remote endpoint acked this */
30 #define RACK_TO_REXT 0x000002/* A timeout occurred on this sendmap entry */
31 #define RACK_DEFERRED 0x000004/* We can't use this for RTT calc - not used */
32 #define RACK_OVERMAX 0x000008/* We have more retran's then we can fit */
33 #define RACK_SACK_PASSED 0x000010/* A sack was done above this block */
34 #define RACK_WAS_SACKPASS 0x000020/* We retransmitted due to SACK pass */
35 #define RACK_HAS_FIN 0x000040/* segment is sent with fin */
36 #define RACK_TLP 0x000080/* segment sent as tail-loss-probe */
37 #define RACK_RWND_COLLAPSED 0x000100/* The peer collapsed the rwnd on the segment */
38 #define RACK_APP_LIMITED 0x000200/* We went app limited after this send */
39 #define RACK_WAS_ACKED 0x000400/* a RTO undid the ack, but it already had a rtt calc done */
40 #define RACK_HAS_SYN 0x000800/* SYN is on this guy */
41 #define RACK_SENT_W_DSACK 0x001000/* Sent with a dsack */
42 #define RACK_SENT_SP 0x002000/* sent in slow path */
43 #define RACK_SENT_FP 0x004000/* sent in fast path */
44 #define RACK_HAD_PUSH 0x008000/* Push was sent on original send */
45 #define RACK_MUST_RXT 0x010000/* We must retransmit this rsm (non-sack/mtu chg)*/
46 #define RACK_IN_GP_WIN 0x020000/* Send was in GP window when sent */
47 #define RACK_SHUFFLED 0x040000/* The RSM was shuffled some data from one to another */
48 #define RACK_MERGED 0x080000/* The RSM was merged */
49 #define RACK_PMTU_CHG 0x100000/* The path mtu changed on this guy */
50 #define RACK_STRADDLE 0x200000/* The seq straddles the bucket line */
51 #define RACK_WAS_LOST 0x400000/* Is the rsm considered lost */
52 #define RACK_IS_PCM 0x800000/* A PCM measurement is being taken */
53 #define RACK_NUM_OF_RETRANS 3
54
55 #define RACK_INITIAL_RTO 1000000 /* 1 second in microseconds */
56
57 #define RACK_REQ_AVG 3 /* Must be less than 256 */
58
59 struct rack_sendmap {
60 TAILQ_ENTRY(rack_sendmap) next;
61 TAILQ_ENTRY(rack_sendmap) r_tnext; /* Time of transmit based next */
62 uint32_t bindex;
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 */
68 uint32_t r_act_rxt_cnt; /* The actual total count of transmits */
69 struct mbuf *m;
70 uint32_t soff;
71 uint32_t orig_m_len; /* The original mbuf len when we sent (can update) */
72 uint32_t orig_t_space; /* The original trailing space when we sent (can update) */
73 uint32_t r_nseq_appl; /* If this one is app limited, this is the nxt seq limited */
74 uint8_t r_dupack; /* Dup ack count */
75 uint8_t r_in_tmap; /* Flag to see if its in the r_tnext array */
76 uint8_t r_limit_type; /* is this entry counted against a limit? */
77 uint8_t r_just_ret : 1, /* After sending, the next pkt was just returned, i.e. limited */
78 r_one_out_nr : 1, /* Special case 1 outstanding and not in recovery */
79 r_no_rtt_allowed : 1, /* No rtt measurement allowed */
80 r_hw_tls : 1,
81 r_avail : 4;
82 uint64_t r_tim_lastsent[RACK_NUM_OF_RETRANS];
83 uint64_t r_ack_arrival; /* This is the time of ack-arrival (if SACK'd) */
84 uint32_t r_fas; /* Flight at send */
85 uint8_t r_bas; /* The burst size (burst at send = bas) */
86 };
87
88 struct deferred_opt_list {
89 TAILQ_ENTRY(deferred_opt_list) next;
90 int optname;
91 uint64_t optval;
92 };
93
94 /*
95 * Timestamps in the rack sendmap are now moving to be
96 * uint64_t's. This means that if you want a uint32_t
97 * usec timestamp (the old usecond timestamp) you simply have
98 * to cast it to uint32_t. The reason we do this is not for
99 * wrap, but we need to get back, at times, to the millisecond
100 * timestamp that is used in the TSTMP option. To do this we
101 * can use the rack_ts_to_msec() inline below which can take
102 * the 64bit ts and make into the correct timestamp millisecond
103 * wise. Thats not possible with the 32bit usecond timestamp since
104 * the seconds wrap too quickly to cover all bases.
105 *
106 * There are quite a few places in rack where I simply cast
107 * back to uint32_t and then end up using the TSTMP_XX()
108 * macros. This is ok, but we could do simple compares if
109 * we ever decided to move all of those variables to 64 bits
110 * as well.
111 */
112
113 static inline uint64_t
rack_to_usec_ts(struct timeval * tv)114 rack_to_usec_ts(struct timeval *tv)
115 {
116 return ((tv->tv_sec * HPTS_USEC_IN_SEC) + tv->tv_usec);
117 }
118
119 static inline uint32_t
rack_ts_to_msec(uint64_t ts)120 rack_ts_to_msec(uint64_t ts)
121 {
122 return((uint32_t)(ts / HPTS_MSEC_IN_SEC));
123 }
124
125
126 TAILQ_HEAD(rack_head, rack_sendmap);
127 TAILQ_HEAD(def_opt_head, deferred_opt_list);
128
129 /* Map change logging */
130 #define MAP_MERGE 0x01
131 #define MAP_SPLIT 0x02
132 #define MAP_NEW 0x03
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
140
141 #define RACK_LIMIT_TYPE_SPLIT 1
142
143 /*
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
148 * b/w estimation.
149 */
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 {
153 uint32_t rs_flags;
154 uint32_t rs_rtt_lowest;
155 uint32_t rs_rtt_highest;
156 uint32_t rs_rtt_cnt;
157 uint32_t rs_us_rtt;
158 int32_t confidence;
159 uint64_t rs_rtt_tot;
160 uint16_t rs_us_rtrcnt;
161 };
162
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
168
169 /*
170 * Magic numbers for logging timeout events if the
171 * logging is enabled.
172 */
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
179
180 #define RCV_PATH_RTT_MS 10 /* How many ms between recv path RTT's */
181
182 struct rack_opts_stats {
183 uint64_t tcp_rack_tlp_reduce;
184 uint64_t tcp_rack_pace_always;
185 uint64_t tcp_rack_pace_reduce;
186 uint64_t tcp_rack_max_seg;
187 uint64_t tcp_rack_prr_sendalot;
188 uint64_t tcp_rack_min_to;
189 uint64_t tcp_rack_early_seg;
190 uint64_t tcp_rack_reord_thresh;
191 uint64_t tcp_rack_reord_fade;
192 uint64_t tcp_rack_tlp_thresh;
193 uint64_t tcp_rack_pkt_delay;
194 uint64_t tcp_rack_tlp_inc_var;
195 uint64_t tcp_tlp_use;
196 uint64_t tcp_rack_idle_reduce;
197 uint64_t tcp_rack_idle_reduce_high;
198 uint64_t rack_no_timer_in_hpts;
199 uint64_t tcp_rack_min_pace_seg;
200 uint64_t tcp_rack_pace_rate_ca;
201 uint64_t tcp_rack_rr;
202 uint64_t tcp_rack_rrr_no_conf_rate;
203 uint64_t tcp_initial_rate;
204 uint64_t tcp_initial_win;
205 uint64_t tcp_hdwr_pacing;
206 uint64_t tcp_gp_inc_ss;
207 uint64_t tcp_gp_inc_ca;
208 uint64_t tcp_gp_inc_rec;
209 uint64_t tcp_rack_force_max_seg;
210 uint64_t tcp_rack_pace_rate_ss;
211 uint64_t tcp_rack_pace_rate_rec;
212 /* Temp counters for dsack */
213 uint64_t tcp_sack_path_1; /* not used */
214 uint64_t tcp_sack_path_2a; /* not used */
215 uint64_t tcp_sack_path_2b; /* not used */
216 uint64_t tcp_sack_path_3; /* not used */
217 uint64_t tcp_sack_path_4; /* not used */
218 /* non temp counters */
219 uint64_t tcp_rack_scwnd;
220 uint64_t tcp_rack_noprr;
221 uint64_t tcp_rack_cfg_rate;
222 uint64_t tcp_timely_dyn;
223 uint64_t tcp_rack_mbufq;
224 uint64_t tcp_fillcw;
225 uint64_t tcp_npush;
226 uint64_t tcp_lscwnd;
227 uint64_t tcp_profile;
228 uint64_t tcp_hdwr_rate_cap;
229 uint64_t tcp_pacing_rate_cap;
230 uint64_t tcp_pacing_up_only;
231 uint64_t tcp_use_cmp_acks;
232 uint64_t tcp_rack_abc_val;
233 uint64_t tcp_rec_abc_val;
234 uint64_t tcp_rack_measure_cnt;
235 uint64_t tcp_rack_delayed_ack;
236 uint64_t tcp_rack_rtt_use;
237 uint64_t tcp_data_after_close;
238 uint64_t tcp_defer_opt;
239 uint64_t tcp_pol_detect;
240 uint64_t tcp_rack_beta;
241 uint64_t tcp_rack_beta_ecn;
242 uint64_t tcp_rack_timer_slop;
243 uint64_t tcp_rack_dsack_opt;
244 uint64_t tcp_rack_hi_beta;
245 uint64_t tcp_split_limit;
246 uint64_t tcp_rack_pacing_divisor;
247 uint64_t tcp_rack_min_seg;
248 uint64_t tcp_dgp_in_rec;
249 uint64_t tcp_notimely;
250 uint64_t tcp_honor_hpts;
251 uint64_t tcp_dyn_rec;
252 uint64_t tcp_fillcw_rate_cap;
253 uint64_t tcp_pol_mss;
254 };
255
256 /* RTT shrink reasons */
257 #define RACK_RTTS_INIT 0
258 #define RACK_RTTS_NEWRTT 1
259 #define RACK_RTTS_EXITPROBE 2
260 #define RACK_RTTS_ENTERPROBE 3
261 #define RACK_RTTS_REACHTARGET 4
262 #define RACK_RTTS_SEEHBP 5
263 #define RACK_RTTS_NOBACKOFF 6
264 #define RACK_RTTS_SAFETY 7
265
266 #define RACK_USE_BEG 1
267 #define RACK_USE_END 2
268 #define RACK_USE_END_OR_THACK 3
269
270 #define TLP_USE_ID 1 /* Internet draft behavior */
271 #define TLP_USE_TWO_ONE 2 /* Use 2.1 behavior */
272 #define TLP_USE_TWO_TWO 3 /* Use 2.2 behavior */
273 #define RACK_MIN_BW 8000 /* 64kbps in Bps */
274
275 #define CCSP_DIS_MASK 0x0001
276 #define HYBRID_DIS_MASK 0x0002
277
278 /* Rack quality indicators for GPUT measurements */
279 #define RACK_QUALITY_NONE 0 /* No quality stated */
280 #define RACK_QUALITY_HIGH 1 /* A normal measurement of a GP RTT */
281 #define RACK_QUALITY_APPLIMITED 2 /* An app limited case that may be of lower quality */
282 #define RACK_QUALITY_PERSIST 3 /* A measurement where we went into persists */
283 #define RACK_QUALITY_PROBERTT 4 /* A measurement where we went into or exited probe RTT */
284 #define RACK_QUALITY_ALLACKED 5 /* All data is now acknowledged */
285
286 #define MIN_GP_WIN 6 /* We need at least 6 MSS in a GP measurement */
287 #ifdef _KERNEL
288 #define RACK_OPTS_SIZE (sizeof(struct rack_opts_stats)/sizeof(uint64_t))
289 extern counter_u64_t rack_opts_arry[RACK_OPTS_SIZE];
290 #define RACK_OPTS_ADD(name, amm) counter_u64_add(rack_opts_arry[(offsetof(struct rack_opts_stats, name)/sizeof(uint64_t))], (amm))
291 #define RACK_OPTS_INC(name) RACK_OPTS_ADD(name, 1)
292 #endif
293 /*
294 * As we get each SACK we wade through the
295 * rc_map and mark off what is acked.
296 * We also increment rc_sacked as well.
297 *
298 * We also pay attention to missing entries
299 * based on the time and possibly mark them
300 * for retransmit. If we do and we are not already
301 * in recovery we enter recovery. In doing
302 * so we claer prr_delivered/holes_rxt and prr_sent_dur_rec.
303 * We also setup rc_next/rc_snd_nxt/rc_send_end so
304 * we will know where to send from. When not in
305 * recovery rc_next will be NULL and rc_snd_nxt should
306 * equal snd_max.
307 *
308 * Whenever we retransmit from recovery we increment
309 * rc_holes_rxt as we retran a block and mark it as retransmitted
310 * with the time it was sent. During non-recovery sending we
311 * add to our map and note the time down of any send expanding
312 * the rc_map at the tail and moving rc_snd_nxt up with snd_max.
313 *
314 * In recovery during SACK/ACK processing if a chunk has
315 * been retransmitted and it is now acked, we decrement rc_holes_rxt.
316 * When we retransmit from the scoreboard we use
317 * rc_next and rc_snd_nxt/rc_send_end to help us
318 * find what needs to be retran.
319 *
320 * To calculate pipe we simply take (snd_max - snd_una) + rc_holes_rxt
321 * This gets us the effect of RFC6675 pipe, counting twice for
322 * bytes retransmitted.
323 */
324
325 #define TT_RACK_FR_TMR 0x2000
326
327 /*
328 * Locking for the rack control block.
329 * a) Locked by INP_WLOCK
330 * b) Locked by the hpts-mutex
331 *
332 */
333 #define RACK_GP_HIST 4 /* How much goodput history do we maintain? */
334 #define RETRAN_CNT_SIZE 16
335
336 #define RACK_NUM_FSB_DEBUG 16
337 #ifdef _KERNEL
338 struct rack_fast_send_blk {
339 uint32_t left_to_send;
340 uint16_t tcp_ip_hdr_len;
341 uint8_t tcp_flags;
342 uint8_t hoplimit;
343 uint8_t *tcp_ip_hdr;
344 uint32_t recwin;
345 uint32_t off;
346 struct tcphdr *th;
347 struct udphdr *udp;
348 struct mbuf *m;
349 uint32_t o_m_len;
350 uint32_t o_t_len;
351 uint32_t rfo_apply_push : 1,
352 hw_tls : 1,
353 unused : 30;
354 };
355
356 struct tailq_hash;
357
358 struct rack_pcm_info {
359 /* Base send time and s/e filled in by rack_log_output */
360 uint64_t send_time;
361 uint32_t sseq;
362 uint32_t eseq;
363 /* Ack's fill in the rest of the data */
364 uint16_t cnt;
365 /* Maximum acks present */
366 uint16_t cnt_alloc;
367 };
368
369 #define RACK_DEFAULT_PCM_ARRAY 16
370
371 struct rack_pcm_stats {
372 uint32_t sseq;
373 uint32_t eseq;
374 uint64_t ack_time;
375 };
376
377
378 struct rack_control {
379 /* Second cache line 0x40 from tcp_rack */
380 struct tailq_hash *tqh; /* Tree of all segments Lock(a) */
381 struct rack_head rc_tmap; /* List in transmit order Lock(a) */
382 struct rack_sendmap *rc_tlpsend; /* Remembered place for
383 * tlp_sending Lock(a) */
384 struct rack_sendmap *rc_resend; /* something we have been asked to
385 * resend */
386 struct rack_fast_send_blk fsb; /* The fast-send block */
387 uint32_t timer_slop;
388 uint16_t pace_len_divisor;
389 uint16_t rc_user_set_min_segs;
390 uint32_t rc_hpts_flags;
391 uint32_t rc_fixed_pacing_rate_ca;
392 uint32_t rc_fixed_pacing_rate_rec;
393 uint32_t rc_fixed_pacing_rate_ss;
394 uint32_t cwnd_to_use; /* The cwnd in use */
395 uint32_t rc_timer_exp; /* If a timer ticks of expiry */
396 uint32_t rc_rack_min_rtt; /* lowest RTT seen Lock(a) */
397 uint32_t rc_rack_largest_cwnd; /* Largest CWND we have seen Lock(a) */
398
399 /* Third Cache line 0x80 */
400 struct rack_head rc_free; /* Allocation array */
401 uint64_t last_hw_bw_req;
402 uint64_t crte_prev_rate;
403 uint64_t bw_rate_cap;
404 uint64_t last_cumack_advance; /* Last time cumack moved forward */
405 uint32_t rc_reorder_ts; /* Last time we saw reordering Lock(a) */
406
407 uint32_t rc_tlp_new_data; /* we need to send new-data on a TLP
408 * Lock(a) */
409 uint32_t rc_prr_out; /* bytes sent during recovery Lock(a) */
410
411 uint32_t rc_prr_recovery_fs; /* recovery fs point Lock(a) */
412
413 uint32_t rc_prr_sndcnt; /* Prr sndcnt Lock(a) */
414
415 uint32_t rc_sacked; /* Tot sacked on scoreboard Lock(a) */
416 uint32_t last_sent_tlp_seq; /* Last tlp sequence that was retransmitted Lock(a) */
417
418 uint32_t rc_prr_delivered; /* during recovery prr var Lock(a) */
419
420 uint16_t rc_tlp_cnt_out; /* count of times we have sent a TLP without new data */
421 uint16_t last_sent_tlp_len; /* Number of bytes in the last sent tlp */
422
423 uint32_t rc_loss_count; /* How many bytes have been retransmitted
424 * Lock(a) */
425 uint32_t rc_reorder_fade; /* Socket option value Lock(a) */
426
427 /* Forth cache line 0xc0 */
428 /* Times */
429
430 uint32_t rc_rack_tmit_time; /* Rack transmit time Lock(a) */
431 uint32_t rc_holes_rxt; /* Tot retraned from scoreboard Lock(a) */
432
433 uint32_t rc_num_maps_alloced; /* Number of map blocks (sacks) we
434 * have allocated */
435 uint32_t rc_rcvtime; /* When we last received data */
436 uint32_t rc_num_split_allocs; /* num split map entries allocated */
437 uint32_t rc_split_limit; /* Limit from control var can be set by socket opt */
438 uint32_t rack_avg_rec_sends;
439
440 uint32_t rc_last_output_to;
441 uint32_t rc_went_idle_time;
442
443 struct rack_sendmap *rc_sacklast; /* sack remembered place
444 * Lock(a) */
445
446 struct rack_sendmap *rc_first_appl; /* Pointer to first app limited */
447 struct rack_sendmap *rc_end_appl; /* Pointer to last app limited */
448 /* Cache line split 0x100 */
449 struct sack_filter rack_sf;
450 /* Cache line split 0x140 */
451 /* Flags for various things */
452 uint32_t rc_pace_max_segs;
453 uint32_t rc_pace_min_segs;
454 uint32_t rc_app_limited_cnt;
455 uint16_t rack_per_of_gp_ss; /* 100 = 100%, so from 65536 = 655 x bw */
456 uint16_t rack_per_of_gp_ca; /* 100 = 100%, so from 65536 = 655 x bw */
457 uint16_t rack_per_of_gp_rec; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */
458 uint16_t rack_per_of_gp_probertt; /* 100 = 100%, so from 65536 = 655 x bw, 0=off */
459 uint32_t rc_high_rwnd;
460 struct rack_rtt_sample rack_rs;
461 const struct tcp_hwrate_limit_table *crte;
462 uint32_t rc_agg_early;
463 uint32_t rc_agg_delayed;
464 uint32_t rc_tlp_rxt_last_time;
465 uint32_t rc_saved_cwnd;
466 uint64_t rc_gp_output_ts; /* chg*/
467 uint64_t rc_gp_cumack_ts; /* chg*/
468 struct timeval act_rcv_time;
469 struct timeval rc_last_time_decay; /* SAD time decay happened here */
470 uint64_t gp_bw;
471 uint64_t init_rate;
472 #ifdef NETFLIX_SHARED_CWND
473 struct shared_cwnd *rc_scw;
474 #endif
475 uint64_t last_gp_comp_bw;
476 uint64_t last_max_bw; /* Our calculated max b/w last */
477 struct time_filter_small rc_gp_min_rtt;
478 struct def_opt_head opt_list;
479 uint64_t lt_bw_time; /* Total time with data outstanding (lt_bw = long term bandwidth) */
480 uint64_t lt_bw_bytes; /* Total bytes acked */
481 uint64_t lt_timemark; /* 64 bit timestamp when we started sending */
482 struct tcp_sendfile_track *rc_last_sft;
483 uint32_t lt_seq; /* Seq at start of lt_bw gauge */
484 int32_t rc_rtt_diff; /* Timely style rtt diff of our gp_srtt */
485 uint64_t last_tmit_time_acked; /* Holds the last cumack point's last send time */
486 /* Recovery stats */
487 uint64_t last_sendtime;
488
489 uint64_t last_gpest;
490 uint64_t last_tm_mark; /* Last tm mark used */
491 uint64_t fillcw_cap; /* B/W cap on fill cw */
492 struct rack_pcm_info pcm_i;
493 struct rack_pcm_stats *pcm_s;
494 uint32_t gp_gain_req; /* Percent off gp gain req */
495 uint32_t last_rnd_of_gp_rise;
496 uint32_t gp_rnd_thresh;
497 uint32_t ss_hi_fs;
498 uint32_t gate_to_fs;
499 uint32_t pcm_max_seg;
500 uint32_t last_pcm_round;
501 uint32_t pcm_idle_rounds;
502
503 uint32_t rc_gp_srtt; /* Current GP srtt */
504 uint32_t rc_prev_gp_srtt; /* Previous RTT */
505 uint32_t rc_entry_gp_rtt; /* Entry to PRTT gp-rtt */
506 uint32_t rc_loss_at_start; /* At measurement window where was our lost value */
507 uint32_t rc_considered_lost; /* Count in recovery of non-retransmitted bytes considered lost */
508
509 uint32_t dsack_round_end; /* In a round of seeing a DSACK */
510 uint32_t current_round; /* Starting at zero */
511 uint32_t roundends; /* acked value above which round ends */
512 uint32_t num_dsack; /* Count of dsack's seen (1 per window)*/
513 uint32_t forced_ack_ts;
514 uint32_t last_collapse_point; /* Last point peer collapsed too */
515 uint32_t high_collapse_point;
516 uint32_t rc_lower_rtt_us_cts; /* Time our GP rtt was last lowered */
517 uint32_t rc_time_probertt_entered;
518 uint32_t rc_time_probertt_starts;
519 uint32_t rc_lowest_us_rtt;
520 uint32_t rc_highest_us_rtt;
521 uint32_t rc_last_us_rtt;
522 uint32_t rc_time_of_last_probertt;
523 uint32_t rc_target_probertt_flight;
524 uint32_t rc_probertt_sndmax_atexit; /* Highest sent to in probe-rtt */
525 uint32_t rc_cwnd_at_erec;
526 uint32_t rc_ssthresh_at_erec;
527 uint32_t dsack_byte_cnt;
528 uint32_t retran_during_recovery;
529 uint32_t rc_gp_lowrtt; /* Lowest rtt seen during GPUT measurement */
530 uint32_t rc_gp_high_rwnd; /* Highest rwnd seen during GPUT measurement */
531 uint32_t rc_snd_max_at_rto; /* For non-sack when the RTO occurred what was snd-max */
532 uint32_t rc_out_at_rto;
533 int32_t rc_scw_index;
534 uint32_t max_reduction;
535 uint32_t side_chan_dis_mask; /* Bit mask of socket opt's disabled */
536 uint32_t rc_tlp_threshold; /* Socket option value Lock(a) */
537 uint32_t rc_last_timeout_snduna;
538 uint32_t last_tlp_acked_start;
539 uint32_t last_tlp_acked_end;
540 uint32_t rc_min_to; /* Socket option value Lock(a) */
541 uint32_t rc_pkt_delay; /* Socket option value Lock(a) */
542 uint32_t persist_lost_ends;
543 uint32_t input_pkt;
544 uint32_t saved_input_pkt;
545 uint32_t cleared_app_ack_seq;
546 uint32_t last_rcv_tstmp_for_rtt;
547 uint32_t last_time_of_arm_rcv;
548 uint32_t rto_ssthresh;
549 struct newreno rc_saved_beta; /*
550 * For newreno cc:
551 * rc_saved_cc are the values we have had
552 * set by the user, if pacing is not happening
553 * (i.e. its early and we have not turned on yet
554 * or it was turned off). The minute pacing
555 * is turned on we pull out the values currently
556 * being used by newreno and replace them with
557 * these values, then save off the old values here,
558 * we also set the flag (if ecn_beta is set) to make
559 * new_reno do less of a backoff for ecn (think abe).
560 */
561 uint16_t rc_cnt_of_retran[RETRAN_CNT_SIZE];
562 uint16_t rc_early_recovery_segs; /* Socket option value Lock(a) */
563 uint16_t rc_reorder_shift; /* Socket option value Lock(a) */
564 uint8_t rack_per_upper_bound_ss;
565 uint8_t rack_per_upper_bound_ca;
566 uint8_t cleared_app_ack;
567 uint8_t dsack_persist;
568 uint8_t rc_no_push_at_mrtt; /* No push when we exceed max rtt */
569 uint8_t num_measurements; /* Number of measurements (up to 0xff, we freeze at 0xff) */
570 uint8_t req_measurements; /* How many measurements are required? */
571 uint8_t saved_hibeta;
572 uint8_t rc_tlp_cwnd_reduce; /* Socket option value Lock(a) */
573 uint8_t rc_prr_sendalot;/* Socket option value Lock(a) */
574 uint8_t rc_rate_sample_method;
575 uint8_t full_dgp_in_rec; /* Flag to say if we do full DGP in recovery */
576 uint8_t client_suggested_maxseg; /* Not sure what to do with this yet */
577 uint8_t use_gp_not_last;
578 uint8_t pacing_method; /* If pace_always, what type of pacing */
579 uint8_t already_had_a_excess;
580 };
581 #endif
582
583 #define RACK_PACING_NONE 0x00
584 #define RACK_DGP_PACING 0x01
585 #define RACK_REG_PACING 0x02
586
587 /* DGP with no buffer level mitigations */
588 #define DGP_LEVEL0 0
589
590 /*
591 * DGP with buffer level mitigation where BL:4 caps fillcw and BL:5
592 * turns off fillcw.
593 */
594 #define DGP_LEVEL1 1
595
596 /*
597 * DGP with buffer level mitigation where BL:3 caps fillcw and BL:4 turns off fillcw
598 * and BL:5 reduces by 10%
599 */
600 #define DGP_LEVEL2 2
601
602 /*
603 * DGP with buffer level mitigation where BL:2 caps fillcw and BL:3 turns off
604 * fillcw BL:4 reduces by 10% and BL:5 reduces by 20%
605 */
606 #define DGP_LEVEL3 3
607
608 /* Hybrid pacing log defines */
609 #define HYBRID_LOG_NO_ROOM 0 /* No room for the clients request */
610 #define HYBRID_LOG_TURNED_OFF 1 /* Turned off hybrid pacing */
611 #define HYBRID_LOG_NO_PACING 2 /* Failed to set pacing on */
612 #define HYBRID_LOG_RULES_SET 3 /* Hybrid pacing for this chunk is set */
613 #define HYBRID_LOG_NO_RANGE 4 /* In DGP mode, no range found */
614 #define HYBRID_LOG_RULES_APP 5 /* The specified rules were applied */
615 #define HYBRID_LOG_REQ_COMP 6 /* The request completed */
616 #define HYBRID_LOG_BW_MEASURE 7 /* Follow up b/w measurements to the previous completed log */
617 #define HYBRID_LOG_RATE_CAP 8 /* We had a rate cap apply */
618 #define HYBRID_LOG_CAP_CALC 9 /* How we calculate the cap */
619 #define HYBRID_LOG_ISSAME 10 /* Same as before -- temp */
620 #define HYBRID_LOG_ALLSENT 11 /* We sent it all no more rate-cap */
621 #define HYBRID_LOG_OUTOFTIME 12 /* We are past the deadline DGP */
622 #define HYBRID_LOG_CAPERROR 13 /* Hit one of the TSNH cases */
623 #define HYBRID_LOG_EXTEND 14 /* We extended the end */
624 #define HYBRID_LOG_SENT_LOST 15 /* A closing sent/lost report */
625
626 #define LOST_ZERO 1 /* Zero it out */
627 #define LOST_ADD 2 /* Add to it */
628 #define LOST_SUB 3 /* Sub from it */
629
630 #define RACK_TIMELY_CNT_BOOST 5 /* At 5th increase boost */
631 #define RACK_MINRTT_FILTER_TIM 10 /* Seconds */
632
633 #define RACK_HYSTART_OFF 0
634 #define RACK_HYSTART_ON 1 /* hystart++ on */
635 #define RACK_HYSTART_ON_W_SC 2 /* hystart++ on +Slam Cwnd */
636 #define RACK_HYSTART_ON_W_SC_C 3 /* hystart++ on,
637 * Conservative ssthresh and
638 * +Slam cwnd
639 */
640
641 #define MAX_USER_SET_SEG 0x3f /* The max we can set is 63 which is probably too many */
642 #define RACK_FREE_CNT_MAX 0x2f /* Max our counter can do */
643
644 #ifdef _KERNEL
645
646 struct tcp_rack {
647 /* First cache line 0x00 */
648 TAILQ_ENTRY(tcp_rack) r_hpts; /* hptsi queue next Lock(b) */
649 int32_t(*r_substate) (struct mbuf *, struct tcphdr *,
650 struct socket *, struct tcpcb *, struct tcpopt *,
651 int32_t, int32_t, uint32_t, int, int, uint8_t); /* Lock(a) */
652 struct tcpcb *rc_tp; /* The tcpcb Lock(a) */
653 struct inpcb *rc_inp; /* The inpcb Lock(a) */
654 uint8_t rc_free_cnt : 6,
655 rc_skip_timely : 1,
656 pcm_enabled : 1; /* Is PCM enabled */
657 uint8_t client_bufferlvl : 3, /* Expected range [0,5]: 0=unset, 1=low/empty */
658 rack_deferred_inited : 1,
659 /* ******************************************************************** */
660 /* Note for details of next two fields see rack_init_retransmit_rate() */
661 /* ******************************************************************** */
662 full_size_rxt: 1,
663 shape_rxt_to_pacing_min : 1,
664 /* ******************************************************************** */
665 rc_ack_required: 1,
666 r_use_hpts_min : 1;
667 uint8_t no_prr_addback : 1,
668 gp_ready : 1,
669 defer_options: 1,
670 dis_lt_bw : 1,
671 rc_ack_can_sendout_data: 1, /*
672 * If set it will override pacing restrictions on not sending
673 * data when the pacing timer is running. I.e. you set this
674 * and an ACK will send data. Default is off and its only used
675 * without pacing when we are doing 5G speed up for there
676 * ack filtering.
677 */
678 rc_pacing_cc_set: 1, /*
679 * If we are pacing (pace_always=1) and we have reached the
680 * point where we start pacing (fixed or gp has reached its
681 * magic gp_ready state) this flag indicates we have set in
682 * values to effect CC's backoff's. If pacing is turned off
683 * then we must restore the values saved in rc_saved_beta,
684 * if its going to gp_ready we need to copy the values into
685 * the CC module and set our flags.
686 *
687 * Note this only happens if the cc name is newreno (CCALGONAME_NEWRENO).
688 */
689
690 rc_rack_tmr_std_based :1,
691 rc_rack_use_dsack: 1;
692 uint8_t rc_dsack_round_seen: 1,
693 rc_last_tlp_acked_set: 1,
694 rc_last_tlp_past_cumack: 1,
695 rc_last_sent_tlp_seq_valid: 1,
696 rc_last_sent_tlp_past_cumack: 1,
697 probe_not_answered: 1,
698 rack_hibeta : 1,
699 lt_bw_up : 1;
700 uint32_t rc_rack_rtt; /* RACK-RTT Lock(a) */
701 uint16_t r_mbuf_queue : 1, /* Do we do mbuf queue for non-paced */
702 rtt_limit_mul : 4, /* muliply this by low rtt */
703 r_limit_scw : 1,
704 r_must_retran : 1, /* For non-sack customers we hit an RTO and new data should be resends */
705 r_use_cmp_ack: 1, /* Do we use compressed acks */
706 r_ent_rec_ns: 1, /* We entered recovery and have not sent */
707 r_might_revert: 1, /* Flag to find out if we might need to revert */
708 r_fast_output: 1, /* Fast output is in progress we can skip the bulk of rack_output */
709 r_fsb_inited: 1,
710 r_rack_hw_rate_caps: 1,
711 r_up_only: 1,
712 r_via_fill_cw : 1,
713 r_rcvpath_rtt_up : 1;
714
715 uint8_t rc_user_set_max_segs : 7, /* Socket option value Lock(a) */
716 rc_fillcw_apply_discount;
717 uint8_t rc_labc; /* Appropriate Byte Counting Value */
718 uint16_t forced_ack : 1,
719 rc_gp_incr : 1,
720 rc_gp_bwred : 1,
721 rc_gp_timely_inc_cnt : 3,
722 rc_gp_timely_dec_cnt : 3,
723 r_use_labc_for_rec: 1,
724 rc_highly_buffered: 1, /* The path is highly buffered */
725 rc_dragged_bottom: 1,
726 rc_pace_dnd : 1, /* The pace do not disturb bit */
727 rc_initial_ss_comp : 1,
728 rc_gp_filled : 1,
729 rc_hw_nobuf : 1;
730 uint8_t r_state : 4, /* Current rack state Lock(a) */
731 rc_catch_up : 1, /* catch up mode in dgp */
732 rc_hybrid_mode : 1, /* We are in hybrid mode */
733 rc_suspicious : 1, /* Suspect sacks have been given */
734 rc_new_rnd_needed: 1;
735 uint8_t rc_tmr_stopped : 7,
736 t_timers_stopped : 1;
737 uint8_t rc_enobuf : 7, /* count of enobufs on connection provides */
738 rc_on_min_to : 1;
739 uint8_t r_timer_override : 1, /* hpts override Lock(a) */
740 r_is_v6 : 1, /* V6 pcb Lock(a) */
741 rc_in_persist : 1,
742 rc_tlp_in_progress : 1,
743 rc_always_pace : 1, /* Socket option value Lock(a) */
744 rc_pace_to_cwnd : 1,
745 rc_pace_fill_if_rttin_range : 1,
746 rc_srtt_measure_made : 1;
747 uint8_t app_limited_needs_set : 1,
748 use_fixed_rate : 1,
749 rc_has_collapsed : 1,
750 use_lesser_lt_bw : 1,
751 cspr_is_fcc : 1,
752 rack_hdrw_pacing : 1, /* We are doing Hardware pacing */
753 rack_hdw_pace_ena : 1, /* Is hardware pacing enabled? */
754 rack_attempt_hdwr_pace : 1; /* Did we attempt hdwr pacing (if allowed) */
755 uint8_t rack_tlp_threshold_use : 3, /* only 1, 2 and 3 used so far */
756 rack_rec_nonrxt_use_cr : 1,
757 rack_enable_scwnd : 1,
758 rack_attempted_scwnd : 1,
759 rack_no_prr : 1,
760 rack_scwnd_is_idle : 1;
761 uint8_t rc_allow_data_af_clo: 1,
762 delayed_ack : 1,
763 set_pacing_done_a_iw : 1,
764 use_rack_rr : 1,
765 alloc_limit_reported : 1,
766 rack_avail : 2,
767 rc_force_max_seg : 1;
768 uint8_t r_early : 1,
769 r_late : 1,
770 r_wanted_output: 1,
771 r_rr_config : 2,
772 r_persist_lt_bw_off : 1,
773 r_collapse_point_valid : 1,
774 dgp_on : 1;
775 uint16_t rto_from_rec: 1,
776 avail_bit: 4,
777 pcm_in_progress: 1,
778 pcm_needed: 1,
779 rc_sendvars_notset : 1, /* Inside rack_init send variables (snd_max/una etc) were not set */
780 rc_gp_rtt_set : 1,
781 rc_gp_dyn_mul : 1,
782 rc_gp_saw_rec : 1,
783 rc_gp_saw_ca : 1,
784 rc_gp_saw_ss : 1,
785 rc_gp_no_rec_chg : 1,
786 in_probe_rtt : 1,
787 measure_saw_probe_rtt : 1;
788 /* Cache line 2 0x40 */
789 struct rack_control r_ctl;
790 } __aligned(CACHE_LINE_SIZE);
791
792
793 void rack_update_pcm_ack(struct tcp_rack *rack, int was_cumack,
794 uint32_t ss, uint32_t es);
795
796 #endif
797 #endif
798