xref: /freebsd/sys/netinet/tcp_stacks/tcp_bbr.h (revision cd0d51baaa4509a1db83251a601d34404d20c990)
1 /*-
2  * Copyright (c) 2016-9
3  *	Netflix Inc.  All rights reserved.
4  *      Author Randall R. Stewart
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * $FreeBSD$
28  */
29 
30 #ifndef _NETINET_TCP_BBR_H_
31 #define _NETINET_TCP_BBR_H_
32 
33 #define BBR_INITIAL_RTO  1000000	/* 1 second in micro-seconds */
34 /* Send map flags */
35 #define BBR_ACKED	  0x0001	/* The remote endpoint acked this */
36 #define BBR_WAS_RENEGED	  0x0002	/* The peer reneged the ack  */
37 #define BBR_RXT_CLEARED	  0x0004	/* ACK Cleared by the RXT timer  */
38 #define BBR_OVERMAX	  0x0008	/* We have more retran's then we can
39 					 * fit */
40 #define BBR_SACK_PASSED   0x0010	/* A sack was done above this block */
41 #define BBR_WAS_SACKPASS  0x0020	/* We retransmitted due to SACK pass */
42 #define BBR_HAS_FIN	  0x0040	/* segment is sent with fin */
43 #define BBR_TLP	  	  0x0080	/* segment sent as tail-loss-probe */
44 #define BBR_HAS_SYN	  0x0100	/* segment has the syn */
45 #define BBR_MARKED_LOST   0x0200	/*
46 					 * This segments is lost and
47 					 * totaled into bbr->rc_ctl.rc_lost
48 					 */
49 #define BBR_RWND_COLLAPSED 0x0400	/* The peer collapsed the rwnd on the segment */
50 #define BBR_NUM_OF_RETRANS 7
51 
52 /* Defines for socket options to set pacing overheads */
53 #define BBR_INCL_ENET_OH 0x01
54 #define BBR_INCL_IP_OH   0x02
55 #define BBR_INCL_TCP_OH  0x03
56 
57 /*
58  * With the addition of both measurement algorithms
59  * I had to move over the size of a
60  * cache line (unfortunately). For now there is
61  * no way around this. We may be able to cut back
62  * at some point I hope.
63  */
64 struct bbr_sendmap {
65 	TAILQ_ENTRY(bbr_sendmap) r_next;	/* seq number arrayed next */
66 	TAILQ_ENTRY(bbr_sendmap) r_tnext;	/* Time of tmit based next */
67 	uint32_t r_start;	/* Sequence number of the segment */
68 	uint32_t r_end;		/* End seq, this is 1 beyond actually */
69 
70 	uint32_t r_rtr_bytes;	/* How many bytes have been retransmitted */
71 	uint32_t r_delivered;	/* Delivered amount at send */
72 
73 	uint32_t r_del_time;	/* The time of the last delivery update */
74 	uint8_t r_rtr_cnt:4,	/* Retran count, index this -1 to get time
75 				 * sent */
76 		unused_bit:1,
77 	        r_is_drain:1,	/* In a draining cycle */
78 		r_app_limited:1,/* We went app limited */
79 	        r_ts_valid:1;	/* Timestamp field is valid (r_del_ack_ts) */
80 	uint8_t r_dupack;	/* Dup ack count */
81 	uint8_t r_in_tmap:1,	/* Flag to see if its in the r_tnext array */
82 	        r_is_smallmap:1,/* Was logged as a small-map send-map item */
83 		r_is_gain:1,	/* Was in gain cycle */
84 		r_bbr_state:5;  /* The BBR state at send */
85 	uint8_t r_limit_type;	/* is this entry counted against a limit? */
86 
87 	uint16_t r_flags;	/* Flags as defined above */
88 	uint16_t r_spare16;
89 	uint32_t r_del_ack_ts;  /* At send what timestamp of peer was (if r_ts_valid set) */
90 	/****************Cache line*****************/
91 	uint32_t r_tim_lastsent[BBR_NUM_OF_RETRANS];
92 	/*
93 	 * Question, should we instead just grab the sending b/w
94 	 * from the filter with the gain and store it in a
95 	 * uint64_t instead?
96 	 */
97 	uint32_t r_first_sent_time; /* Time of first pkt in flight sent */
98 	uint32_t r_pacing_delay;	/* pacing delay of this send */
99 	uint32_t r_flight_at_send;	/* flight at the time of the send */
100 #ifdef _KERNEL
101 }           __aligned(CACHE_LINE_SIZE);
102 #else
103 };
104 #endif
105 #define BBR_LIMIT_TYPE_SPLIT	1
106 
107 TAILQ_HEAD(bbr_head, bbr_sendmap);
108 
109 #define BBR_SEGMENT_TIME_SIZE 1500	/* How many bytes in time_between */
110 
111 #define BBR_MIN_SEG 1460		/* MSS size */
112 #define BBR_MAX_GAIN_VALUE 0xffff
113 
114 #define BBR_TIMER_FUDGE  1500	/* 1.5ms in micro seconds */
115 
116 /* BW twiddle secret codes */
117 #define BBR_RED_BW_CONGSIG  	 0	/* We enter recovery and set using b/w */
118 #define BBR_RED_BW_RATECAL  	 1	/* We are calculating the loss rate */
119 #define BBR_RED_BW_USELRBW       2	/* We are dropping the lower b/w with
120 					 * cDR */
121 #define BBR_RED_BW_SETHIGHLOSS	 3	/* We have set our highloss value at
122 					 * exit from probe-rtt */
123 #define BBR_RED_BW_PE_CLREARLY	 4	/* We have decided to clear the
124 					 * reduction early */
125 #define BBR_RED_BW_PE_CLAFDEL	 5	/* We are clearing it on schedule
126 					 * delayed */
127 #define BBR_RED_BW_REC_ENDCLL	 6	/* Recover exits save high if needed
128 					 * an clear to start measuring */
129 #define BBR_RED_BW_PE_NOEARLY_OUT 7	/* Set pkt epoch judged that we do not
130 					 * get out of jail early */
131 /* For calculating a rate */
132 #define BBR_CALC_BW 	1
133 #define BBR_CALC_LOSS  	2
134 
135 #define BBR_RTT_BY_TIMESTAMP	0
136 #define BBR_RTT_BY_EXACTMATCH	1
137 #define BBR_RTT_BY_EARLIER_RET	2
138 #define BBR_RTT_BY_THIS_RETRAN  3
139 #define BBR_RTT_BY_SOME_RETRAN	4
140 #define BBR_RTT_BY_TSMATCHING	5
141 
142 /* Markers to track where we enter persists from */
143 #define BBR_PERSISTS_FROM_1	1
144 #define BBR_PERSISTS_FROM_2	2
145 #define BBR_PERSISTS_FROM_3	3
146 #define BBR_PERSISTS_FROM_4	4
147 #define BBR_PERSISTS_FROM_5	5
148 
149 /* magic cookies to ask for the RTT */
150 #define BBR_RTT_PROP    0
151 #define BBR_RTT_RACK    1
152 #define BBR_RTT_PKTRTT  2
153 #define BBR_SRTT	3
154 
155 #define BBR_SACKED 0
156 #define BBR_CUM_ACKED  1
157 
158 /* threshold in useconds where we consider we need a higher min cwnd */
159 #define BBR_HIGH_SPEED 1000
160 #define BBR_HIGHSPEED_NUM_MSS 12
161 
162 #define MAX_REDUCE_RXT 3	/* What is the maximum times we are willing to
163 				 * reduce b/w in RTX's. Setting this has a
164 				 * multiplicative effect e.g. if we are
165 				 * reducing by 20% then setting it to 3 means
166 				 * you will have reduced the b/w estimate by >
167 				 * 60% before you stop. */
168 /*
169  * We use the rate sample structure to
170  * assist in single sack/ack rate and rtt
171  * calculation. In the future we will expand
172  * this in BBR to do forward rate sample
173  * b/w estimation.
174  */
175 #define BBR_RS_RTT_EMPTY 0x00000001	/* Nothing yet stored in RTT's */
176 #define BBR_RS_BW_EMPTY  0x00000002	/* Nothing yet stored in cDR */
177 #define BBR_RS_RTT_VALID 0x00000004	/* We have at least one valid RTT */
178 #define BBR_RS_BW_VAILD  0x00000008	/* We have a valid cDR */
179 #define BBR_RS_EMPTY   (BBR_RS_RTT_EMPTY|BBR_RS_BW_EMPTY)
180 struct bbr_rtt_sample {
181 	uint32_t rs_flags;
182 	uint32_t rs_rtt_lowest;
183 	uint32_t rs_rtt_lowest_sendtime;
184 	uint32_t rs_rtt_low_seq_start;
185 
186 	uint32_t rs_rtt_highest;
187 	uint32_t rs_rtt_cnt;
188 
189 	uint64_t rs_rtt_tot;
190 	uint32_t cur_rtt;
191 	uint32_t cur_rtt_bytecnt;
192 
193 	uint32_t cur_rtt_rsmcnt;
194 	uint32_t rc_crtt_set:1,
195 		avail_bits:31;
196 	uint64_t rs_cDR;
197 };
198 
199 /* RTT shrink reasons */
200 #define BBR_RTTS_INIT     0
201 #define BBR_RTTS_NEWRTT   1
202 #define BBR_RTTS_RTTPROBE 2
203 #define BBR_RTTS_WASIDLE  3
204 #define BBR_RTTS_PERSIST  4
205 #define BBR_RTTS_REACHTAR 5
206 #define BBR_RTTS_ENTERPROBE 6
207 #define BBR_RTTS_SHRINK_PG 7
208 #define BBR_RTTS_SHRINK_PG_FINAL 8
209 #define BBR_RTTS_NEW_TARGET 9
210 #define BBR_RTTS_LEAVE_DRAIN 10
211 #define BBR_RTTS_RESETS_VALUES 11
212 
213 #define BBR_NUM_RATES 5
214 /* Rate flags */
215 #define BBR_RT_FLAG_FREE       0x00	/* Is on the free list */
216 #define BBR_RT_FLAG_INUSE      0x01	/* Has been allocated */
217 #define BBR_RT_FLAG_READY      0x02	/* Ready to initiate a measurement. */
218 #define BBR_RT_FLAG_CAPPED_PRE 0x04	/* Ready to cap if we send the next segment */
219 #define BBR_RT_FLAG_CAPPED     0x08	/* Measurement is capped */
220 #define BBR_RT_FLAG_PASTFA     0x10	/* Past the first ack. */
221 #define BBR_RT_FLAG_LIMITED    0x20	/* Saw application/cwnd or rwnd limited period */
222 #define BBR_RT_SEEN_A_ACK      0x40	/* A ack has been saved */
223 #define BBR_RT_PREV_RTT_SET    0x80	/* There was a RTT set in */
224 #define BBR_RT_PREV_SEND_TIME  0x100	/*
225 					 *There was a RTT send time set that can be used
226 					 * no snd_limits
227 					 */
228 #define BBR_RT_SET_GRADIENT    0x200
229 #define BBR_RT_TS_VALID        0x400
230 
231 
232 struct bbr_log {
233 	union {
234 		struct bbr_sendmap *rsm;	/* For alloc/free */
235 		uint64_t sb_acc;	/* For out/ack or t-o */
236 	};
237 	struct tcpcb *tp;
238 	uint32_t t_flags;
239 	uint32_t th_seq;
240 	uint32_t th_ack;
241 	uint32_t snd_una;
242 	uint32_t snd_nxt;
243 	uint32_t snd_max;
244 	uint32_t snd_cwnd;
245 	uint32_t snd_wnd;
246 	uint32_t rc_lost;
247 	uint32_t target_cwnd;	/* UU */
248 	uint32_t inflight;	/* UU */
249 	uint32_t applimited;	/* UU */
250 	/* Things for BBR */
251 	uint32_t delivered;	/* UU */
252 	uint64_t cur_del_rate;	/* UU */
253 	uint64_t delRate;	/* UU */
254 	uint64_t rttProp;	/* UU */
255 	uint64_t lt_bw;		/* UU */
256 	uint32_t timeStamp;
257 	uint32_t time;
258 	uint32_t slot;		/* UU */
259 	uint32_t delayed_by;
260 	uint32_t exp_del;
261 	uint32_t pkts_out;
262 	uint32_t new_win;
263 	uint32_t hptsi_gain;	/* UU */
264 	uint32_t cwnd_gain;	/* UU */
265 	uint32_t epoch;		/* UU */
266 	uint32_t lt_epoch;	/* UU */
267 	/* Sack fun */
268 	uint32_t blk_start[4];	/* xx */
269 	uint32_t blk_end[4];
270 	uint32_t len;		/* Timeout T3=1, TLP=2, RACK=3 */
271 	uint8_t type;
272 	uint8_t n_sackblks;
273 	uint8_t applied;	/* UU */
274 	uint8_t inhpts;		/* UU */
275 	uint8_t ininput;	/* UU */
276 	uint8_t use_lt_bw;	/* UU */
277 };
278 
279 struct bbr_log_sysctl_out {
280 	uint32_t bbr_log_at;
281 	uint32_t bbr_log_max;
282 	struct bbr_log entries[0];
283 };
284 
285 /*
286  * Magic numbers for logging timeout events if the
287  * logging is enabled.
288  */
289 #define BBR_TO_FRM_TMR  1
290 #define BBR_TO_FRM_TLP  2
291 #define BBR_TO_FRM_RACK 3
292 #define BBR_TO_FRM_KEEP 4
293 #define BBR_TO_FRM_PERSIST 5
294 #define BBR_TO_FRM_DELACK 6
295 
296 #define BBR_SEES_STRETCH_ACK 1
297 #define BBR_SEES_COMPRESSED_ACKS 2
298 
299 
300 /*
301  * As we get each SACK we wade through the
302  * rc_map and mark off what is acked.
303  * We also increment rc_sacked as well.
304  *
305  * We also pay attention to missing entries
306  * based on the time and possibly mark them
307  * for retransmit. If we do and we are not already
308  * in recovery we enter recovery. In doing
309  * so we claer prr_delivered/holes_rxt and prr_sent_dur_rec.
310  * We also setup rc_next/rc_snd_nxt/rc_send_end so
311  * we will know where to send from. When not in
312  * recovery rc_next will be NULL and rc_snd_nxt should
313  * equal snd_max.
314  *
315  * Whenever we retransmit from recovery we increment
316  * rc_holes_rxt as we retran a block and mark it as retransmitted
317  * with the time it was sent. During non-recovery sending we
318  * add to our map and note the time down of any send expanding
319  * the rc_map at the tail and moving rc_snd_nxt up with snd_max.
320  *
321  * In recovery during SACK/ACK processing if a chunk has
322  * been retransmitted and it is now acked, we decrement rc_holes_rxt.
323  * When we retransmit from the scoreboard we use
324  * rc_next and rc_snd_nxt/rc_send_end to help us
325  * find what needs to be retran.
326  *
327  * To calculate pipe we simply take (snd_max - snd_una) + rc_holes_rxt
328  * This gets us the effect of RFC6675 pipe, counting twice for
329  * bytes retransmitted.
330  */
331 
332 #define TT_BBR_FR_TMR	0x2001
333 
334 #define BBR_SCALE 8
335 #define BBR_UNIT (1 << BBR_SCALE)
336 
337 #define BBR_NUM_RTTS_FOR_DEL_LIMIT 8	/* How many pkt-rtts do we keep
338 					 * Delivery rate for */
339 #define BBR_NUM_RTTS_FOR_GOOG_DEL_LIMIT 10	/* How many pkt-rtts do we keep
340 						 * Delivery rate for google */
341 
342 #define BBR_SECONDS_NO_RTT 10	/* 10 seconds with no RTT shrinkage */
343 #define BBR_PROBERTT_MAX 200	/* 200ms */
344 #define BBR_PROBERTT_NUM_MSS 4
345 #define BBR_STARTUP_EPOCHS 3
346 #define USECS_IN_MSEC 1000
347 #define BBR_TIME_TO_SECONDS(a) (a / USECS_IN_SECOND)
348 #define BBR_TIME_TO_MILLI(a) (a / MS_IN_USEC)
349 
350 
351 /* BBR keeps time in usec's so we divide by 1000 and round up */
352 #define BBR_TS_TO_MS(t)  ((t+999)/MS_IN_USEC)
353 
354 /*
355  * Locking for the rack control block.
356  * a) Locked by INP_WLOCK
357  * b) Locked by the hpts-mutex
358  *
359  */
360 #define BBR_STATE_STARTUP   0x01
361 #define BBR_STATE_DRAIN     0x02
362 #define BBR_STATE_PROBE_BW  0x03
363 #define BBR_STATE_PROBE_RTT 0x04
364 #define BBR_STATE_IDLE_EXIT 0x05
365 
366 /* Substate defines for STATE == PROBE_BW */
367 #define BBR_SUB_GAIN  0		/* State 0 where we are 5/4 BBR_UNIT */
368 #define BBR_SUB_DRAIN 1		/* State 1 where we are at 3/4 BBR_UNIT */
369 #define BBR_SUB_LEVEL1 2	/* State 1 first BBR_UNIT */
370 #define BBR_SUB_LEVEL2 3	/* State 2nd BBR_UNIT */
371 #define BBR_SUB_LEVEL3 4	/* State 3rd BBR_UNIT */
372 #define BBR_SUB_LEVEL4 5	/* State 4th BBR_UNIT */
373 #define BBR_SUB_LEVEL5 6	/* State 5th BBR_UNIT */
374 #define BBR_SUB_LEVEL6 7	/* State last BBR_UNIT */
375 #define BBR_SUBSTATE_COUNT 8
376 
377 /* Single remaining reduce log */
378 #define BBR_REDUCE_AT_FR 5
379 
380 #define BBR_BIG_LOG_SIZE 300000
381 
382 struct bbr_stats {
383 	uint64_t bbr_badfr;		/* 0 */
384 	uint64_t bbr_badfr_bytes;	/* 1 */
385 	uint64_t bbr_saw_oerr;		/* 2 */
386 	uint64_t bbr_saw_emsgsiz;	/* 3 */
387 	uint64_t bbr_reorder_seen;	/* 4 */
388 	uint64_t bbr_tlp_tot;		/* 5 */
389 	uint64_t bbr_tlp_newdata;	/* 6 */
390 	uint64_t bbr_offset_recovery;	/* 7 */
391 	uint64_t bbr_tlp_retran_fail;	/* 8 */
392 	uint64_t bbr_to_tot;		/* 9 */
393 	uint64_t bbr_to_arm_rack;	/* 10 */
394 	uint64_t bbr_enter_probertt;	/* 11 */
395 	uint64_t bbr_tlp_set;		/* 12 */
396 	uint64_t bbr_resends_set;	/* 13 */
397 	uint64_t bbr_force_output;	/* 14 */
398 	uint64_t bbr_to_arm_tlp;	/* 15 */
399 	uint64_t bbr_paced_segments;	/* 16 */
400 	uint64_t bbr_saw_enobuf;	/* 17 */
401 	uint64_t bbr_to_alloc_failed;	/* 18 */
402 	uint64_t bbr_to_alloc_emerg;	/* 19 */
403 	uint64_t bbr_sack_proc_all;	/* 20 */
404 	uint64_t bbr_sack_proc_short;	/* 21 */
405 	uint64_t bbr_sack_proc_restart;	/* 22 */
406 	uint64_t bbr_to_alloc;		/* 23 */
407 	uint64_t bbr_offset_drop;	/* 24 */
408 	uint64_t bbr_runt_sacks;	/* 25 */
409 	uint64_t bbr_sack_passed;	/* 26 */
410 	uint64_t bbr_rlock_left_ret0;	/* 27 */
411 	uint64_t bbr_rlock_left_ret1;	/* 28 */
412 	uint64_t bbr_dynamic_rwnd;	/* 29 */
413 	uint64_t bbr_static_rwnd;	/* 30 */
414 	uint64_t bbr_sack_blocks;	/* 31 */
415 	uint64_t bbr_sack_blocks_skip;	/* 32 */
416 	uint64_t bbr_sack_search_both;	/* 33 */
417 	uint64_t bbr_sack_search_fwd;	/* 34 */
418 	uint64_t bbr_sack_search_back;	/* 35 */
419 	uint64_t bbr_plain_acks;	/* 36 */
420 	uint64_t bbr_acks_with_sacks;	/* 37 */
421 	uint64_t bbr_progress_drops;	/* 38 */
422 	uint64_t bbr_early;		/* 39 */
423 	uint64_t bbr_reneges_seen;	/* 40 */
424 	uint64_t bbr_persist_reneg;	/* 41 */
425 	uint64_t bbr_dropped_af_data;	/* 42 */
426 	uint64_t bbr_failed_mbuf_aloc;	/* 43 */
427 	uint64_t bbr_cwnd_limited;	/* 44 */
428 	uint64_t bbr_rwnd_limited;	/* 45 */
429 	uint64_t bbr_app_limited;	/* 46 */
430 	uint64_t bbr_force_timer_start;	/* 47 */
431 	uint64_t bbr_hpts_min_time;	/* 48 */
432 	uint64_t bbr_meets_tso_thresh;  /* 49 */
433 	uint64_t bbr_miss_tso_rwnd;	/* 50 */
434 	uint64_t bbr_miss_tso_cwnd;	/* 51 */
435 	uint64_t bbr_miss_tso_app;	/* 52 */
436 	uint64_t bbr_miss_retran;	/* 53 */
437 	uint64_t bbr_miss_tlp;		/* 54 */
438 	uint64_t bbr_miss_unknown;	/* 55 */
439 	uint64_t bbr_hdwr_rl_add_ok;	/* 56 */
440 	uint64_t bbr_hdwr_rl_add_fail;	/* 57 */
441 	uint64_t bbr_hdwr_rl_mod_ok;	/* 58 */
442 	uint64_t bbr_hdwr_rl_mod_fail;	/* 59 */
443 	uint64_t bbr_collapsed_win;     /* 60 */
444 	uint64_t bbr_alloc_limited;	/* 61 */
445 	uint64_t bbr_alloc_limited_conns; /* 62 */
446 	uint64_t bbr_split_limited;	/* 63 */
447 };
448 
449 /*
450  * The structure bbr_opt_stats is a simple
451  * way to see how many options are being
452  * changed in the stack.
453  */
454 struct bbr_opts_stats {
455 	uint64_t tcp_bbr_pace_per_sec;
456 	uint64_t tcp_bbr_pace_del_tar;
457 	uint64_t tcp_bbr_pace_seg_max;
458 	uint64_t tcp_bbr_pace_seg_min;
459 	uint64_t tcp_bbr_pace_cross;
460 	uint64_t tcp_bbr_drain_inc_extra;
461 	uint64_t tcp_bbr_unlimited;
462 	uint64_t tcp_bbr_iwintso;
463 	uint64_t tcp_bbr_rec_over_hpts;
464 	uint64_t tcp_bbr_recforce;
465 	uint64_t tcp_bbr_startup_pg;
466 	uint64_t tcp_bbr_drain_pg;
467 	uint64_t tcp_bbr_rwnd_is_app;
468 	uint64_t tcp_bbr_probe_rtt_int;
469 	uint64_t tcp_bbr_one_retran;
470 	uint64_t tcp_bbr_startup_loss_exit;
471 	uint64_t tcp_bbr_use_lowgain;
472 	uint64_t tcp_bbr_lowgain_thresh;
473 	uint64_t tcp_bbr_lowgain_half;
474 	uint64_t tcp_bbr_lowgain_fd;
475 	uint64_t tcp_bbr_usedel_rate;
476 	uint64_t tcp_bbr_min_rto;
477 	uint64_t tcp_bbr_max_rto;
478 	uint64_t tcp_rack_pace_max_seg;
479 	uint64_t tcp_rack_min_to;
480 	uint64_t tcp_rack_reord_thresh;
481 	uint64_t tcp_rack_reord_fade;
482 	uint64_t tcp_rack_tlp_thresh;
483 	uint64_t tcp_rack_pkt_delay;
484 	uint64_t tcp_bbr_startup_exit_epoch;
485 	uint64_t tcp_bbr_ack_comp_alg;
486 	uint64_t tcp_rack_cheat;
487 	uint64_t tcp_iwnd_tso;
488 	uint64_t tcp_utter_max_tso;
489 	uint64_t tcp_hdwr_pacing;
490 	uint64_t tcp_extra_state;
491 	uint64_t tcp_floor_min_tso;
492 	/* New */
493 	uint64_t tcp_bbr_algorithm;
494 	uint64_t tcp_bbr_tslimits;
495 	uint64_t tcp_bbr_probertt_len;
496 	uint64_t tcp_bbr_probertt_gain;
497 	uint64_t tcp_bbr_topaceout;
498 	uint64_t tcp_use_rackcheat;
499 	uint64_t tcp_delack;
500 	uint64_t tcp_maxpeak;
501 	uint64_t tcp_retran_wtso;
502 	uint64_t tcp_data_ac;
503 	uint64_t tcp_ts_raises;
504 	uint64_t tcp_pacing_oh_tmr;
505 	uint64_t tcp_pacing_oh;
506 	uint64_t tcp_policer_det;
507 };
508 
509 
510 #ifdef _KERNEL
511 #define BBR_STAT_SIZE (sizeof(struct bbr_stats)/sizeof(uint64_t))
512 extern counter_u64_t bbr_stat_arry[BBR_STAT_SIZE];
513 #define BBR_STAT_ADD(name, amm) counter_u64_add(bbr_stat_arry[(offsetof(struct bbr_stats, name)/sizeof(uint64_t))], (amm))
514 #define BBR_STAT_INC(name) BBR_STAT_ADD(name, 1)
515 #define BBR_OPTS_SIZE (sizeof(struct bbr_stats)/sizeof(uint64_t))
516 extern counter_u64_t bbr_opts_arry[BBR_OPTS_SIZE];
517 #define BBR_OPTS_ADD(name, amm) counter_u64_add(bbr_opts_arry[(offsetof(struct bbr_opts_stats, name)/sizeof(uint64_t))], (amm))
518 #define BBR_OPTS_INC(name) BBR_OPTS_ADD(name, 1)
519 #endif
520 
521 #define BBR_NUM_LOSS_RATES 3
522 #define BBR_NUM_BW_RATES 3
523 
524 #define BBR_RECOVERY_LOWRTT 1
525 #define BBR_RECOVERY_MEDRTT 2
526 #define BBR_RECOVERY_HIGHRTT 3
527 #define BBR_RECOVERY_EXTREMERTT 4
528 
529 
530 struct bbr_control {
531 	/*******************************/
532 	/* Cache line 2 from bbr start */
533 	/*******************************/
534 	struct bbr_head rc_map;	/* List of all segments Lock(a) */
535 	struct bbr_head rc_tmap;	/* List in transmit order Lock(a) */
536 	struct bbr_sendmap *rc_resend;	/* something we have been asked to
537 					 * resend */
538 	uint32_t rc_last_delay_val;	/* How much we expect to delay Lock(a) */
539 	uint32_t rc_bbr_hptsi_gain:16,	/* Current hptsi gain Lock(a) */
540 	         rc_hpts_flags:16;	/* flags on whats on the pacer wheel */
541 
542 	uint32_t rc_delivered;	/* BRR delivered amount Lock(a) */
543 	uint32_t rc_hptsi_agg_delay;	/* How much time are we behind */
544 
545 	uint32_t rc_flight_at_input;
546 	uint32_t rc_lost_bytes;		/* Total bytes currently marked lost */
547 	/*******************************/
548 	/* Cache line 3 from bbr start */
549 	/*******************************/
550 	struct time_filter rc_delrate;
551 	/*******************************/
552 	/* Cache line 4 from bbr start */
553 	/*******************************/
554 	struct bbr_head rc_free;	/* List of Free map entries Lock(a) */
555 	struct bbr_sendmap *rc_tlp_send;	/* something we have been
556 						 * asked to resend */
557 	uint32_t rc_del_time;
558 	uint32_t rc_target_at_state;	/* Target for a state */
559 
560 	uint16_t rc_free_cnt;	/* Number of free entries on the rc_free list
561 				 * Lock(a) */
562 	uint16_t rc_startup_pg;
563 
564 	uint32_t cur_rtt;	/* Last RTT from ack */
565 
566 
567 	uint32_t rc_went_idle_time;	/* Used for persits to see if its
568 					 * probe-rtt qualified */
569 	uint32_t rc_pace_max_segs:17,	/* How much in any single TSO we send Lock(a) */
570 		 rc_pace_min_segs:15;	/* The minimum single segment size before we enter persists */
571 
572 	uint32_t rc_rtt_shrinks;	/* Time of last rtt shrinkage Lock(a) */
573 	uint32_t r_app_limited_until;
574 	uint32_t rc_timer_exp;	/* If a timer ticks of expiry */
575 	uint32_t rc_rcv_epoch_start;	/* Start time of the Epoch Lock(a) */
576 
577 	/*******************************/
578 	/* Cache line 5 from bbr start */
579 	/*******************************/
580 
581 	uint32_t rc_lost_at_pktepoch;	/* what the lost value was at the last
582 					 * pkt-epoch */
583 	uint32_t r_measurement_count;	/* count of measurement applied lock(a) */
584 
585 
586 	uint32_t rc_last_tlp_seq;	/* Last tlp sequence Lock(a) */
587 	uint16_t rc_reorder_shift;	/* Socket option value Lock(a) */
588 	uint16_t rc_pkt_delay;	/* Socket option value Lock(a) */
589 
590 	struct bbr_sendmap *rc_sacklast;	/* sack remembered place
591 						 * Lock(a) */
592 	struct bbr_sendmap *rc_next;	/* remembered place where we next
593 					 * retransmit at Lock(a) */
594 
595 	uint32_t rc_sacked;	/* Tot sacked on scoreboard Lock(a) */
596 	uint32_t rc_holes_rxt;	/* Tot retraned from scoreboard Lock(a) */
597 
598 	uint32_t rc_reorder_ts;	/* Last time we saw reordering Lock(a) */
599 	uint32_t rc_init_rwnd;	/* Initial rwnd when we transitioned */
600                                 /*- ---
601 				 * used only inital and close
602                                  */
603 	uint32_t rc_high_rwnd;	/* Highest rwnd seen */
604 	uint32_t rc_lowest_rtt;	/* Smallest RTT we have seen */
605 
606 	uint32_t rc_last_rtt;	/* Last valid measured RTT that ack'd data */
607 	uint32_t bbr_cross_over;
608 
609 	/*******************************/
610 	/* Cache line 6 from bbr start */
611 	/*******************************/
612 	struct sack_filter bbr_sf;
613 
614 	/*******************************/
615 	/* Cache line 7 from bbr start */
616 	/*******************************/
617 	struct time_filter_small rc_rttprop;
618 	uint32_t last_inbound_ts;	/* Peers last timestamp */
619 
620 	uint32_t rc_inc_tcp_oh: 1,
621 		 rc_inc_ip_oh: 1,
622 		 rc_inc_enet_oh:1,
623 		 rc_incr_tmrs:1,
624 		 restrict_growth:28;
625 	uint32_t rc_lt_epoch_use;	/* When we started lt-bw use Lock(a) */
626 
627 	uint32_t rc_recovery_start;	/* Time we start recovery Lock(a) */
628 	uint32_t rc_lt_del;	/* Delivered at lt bw sampling start Lock(a) */
629 
630 	uint64_t rc_bbr_cur_del_rate;	/* Current measured delivery rate
631 					 * Lock(a) */
632 
633 	/*******************************/
634 	/* Cache line 8 from bbr start */
635 	/*******************************/
636 	uint32_t rc_cwnd_on_ent;	/* On entry to recovery the cwnd
637 					 * Lock(a) */
638 	uint32_t rc_agg_early;	/* aggregate amount early */
639 
640 	uint32_t rc_rcvtime;	/* When we last received data Lock(a) */
641 	uint32_t rc_pkt_epoch_del;	/* seq num that we need for RTT epoch */
642 
643 	uint32_t rc_pkt_epoch;	/* Epoch based on packet RTTs */
644 	uint32_t rc_pkt_epoch_time;	/* Time we started the pkt epoch */
645 
646 	uint32_t rc_pkt_epoch_rtt;	/* RTT using the packet epoch */
647 	uint32_t rc_rtt_epoch;	/* Current RTT epoch, it ticks every rttProp
648 				 * Lock(a) */
649 	uint32_t lowest_rtt;
650 	uint32_t bbr_smallest_srtt_this_state;
651 
652 	uint32_t rc_lt_epoch;	/* LT epoch start of bw_sampling */
653 	uint32_t rc_lost_at_startup;
654 
655 	uint32_t rc_bbr_state_atflight;
656 	uint32_t rc_bbr_last_startup_epoch;	/* Last startup epoch where we
657 						 * increased 20% */
658 	uint32_t rc_bbr_enters_probertt;	/* Timestamp we entered
659 						 * probertt Lock(a) */
660 	uint32_t rc_lt_time;	/* Time of lt sampling start Lock(a) */
661 
662 	/*******************************/
663 	/* Cache line 9 from bbr start */
664 	/*******************************/
665 	uint64_t rc_lt_bw;	/* LT bw calculated Lock(a) */
666 	uint64_t rc_bbr_lastbtlbw;	/* For startup, what was last btlbw I
667 					 * saw to check the 20% gain Lock(a) */
668 
669 
670 	uint32_t rc_bbr_cwnd_gain;	/* Current cwnd gain Lock(a) */
671 	uint32_t rc_pkt_epoch_loss_rate;	/* pkt-epoch loss rate */
672 
673 	uint32_t rc_saved_cwnd;	/* Saved cwnd during Probe-rtt drain Lock(a) */
674 	uint32_t substate_pe;
675 
676 	uint32_t rc_lost;	/* Number of bytes lost Lock(a) */
677 	uint32_t rc_exta_time_gd; /* How much extra time we got in d/g */
678 
679 	uint32_t rc_lt_lost;	/* Number of lt bytes lost at sampling start
680 				 * Lock(a) */
681 	uint32_t rc_bbr_state_time;
682 
683 	uint32_t rc_min_to;	/* Socket option value Lock(a) */
684 	uint32_t rc_initial_hptsi_bw;	/* Our initial startup bw Lock(a) */
685 
686 	uint32_t bbr_lost_at_state;	/* Temp counter debug lost value as we
687 					 * enter a state */
688 	/*******************************/
689 	/* Cache line 10 from bbr start */
690 	/*******************************/
691 	uint32_t rc_level_state_extra;
692 	uint32_t rc_red_cwnd_pe;
693 	const struct tcp_hwrate_limit_table *crte;
694 	uint64_t red_bw;
695 
696 	uint32_t rc_probertt_int;
697 	uint32_t rc_probertt_srttchktim;	/* Time we last did a srtt
698 						 * check  */
699 	uint32_t gain_epoch;	/* Epoch we should be out of gain */
700 	uint32_t rc_min_rto_ms;
701 
702 	uint32_t rc_reorder_fade;	/* Socket option value Lock(a) */
703 	uint32_t last_startup_measure;
704 
705 	int32_t bbr_hptsi_per_second;
706 	int32_t bbr_hptsi_segments_delay_tar;
707 
708 	int32_t bbr_hptsi_segments_max;
709 	uint32_t bbr_rttprobe_gain_val;
710 	/*******************************/
711 	/* Cache line 11 from bbr start */
712 	/*******************************/
713 	uint32_t cur_rtt_send_time;	/* Time we sent our rtt measured packet */
714 	uint32_t bbr_peer_tsratio;	/* Our calculated ts ratio to multply */
715 	uint32_t bbr_ts_check_tstmp;	/* When we filled it the TS that came on the ack */
716 	uint32_t bbr_ts_check_our_cts;	/* When we filled it the cts of the send */
717 	uint32_t rc_tlp_rxt_last_time;
718 	uint32_t bbr_smallest_srtt_state2;
719 	uint32_t bbr_hdwr_cnt_noset_snt;	/* count of hw pacing sends during delay */
720 	uint32_t startup_last_srtt;
721 	uint32_t rc_ack_hdwr_delay;
722 	uint32_t highest_hdwr_delay;		/* Largest delay we have seen from hardware */
723 	uint32_t non_gain_extra;
724 	uint32_t recovery_lr;			/* The sum of the loss rate from the pe's during recovery */
725 	uint32_t last_in_probertt;
726 	uint32_t flightsize_at_drain;		/* In draining what was the last marked flight size */
727 	uint32_t rc_pe_of_prtt;			/* PE we went into probe-rtt */
728 	uint32_t ts_in;				/* ts that went with the last rtt */
729 
730 	uint16_t rc_tlp_seg_send_cnt;	/* Number of times we have TLP sent
731 					 * rc_last_tlp_seq Lock(a) */
732 	uint16_t rc_drain_pg;
733 	uint32_t rc_num_maps_alloced;		/* num send map entries allocated */
734 	uint32_t rc_num_split_allocs;		/* num split map entries allocated */
735 	uint16_t rc_num_small_maps_alloced;	/* Number of sack blocks
736 						 * allocated */
737 	uint16_t bbr_hptsi_bytes_min;
738 
739 	uint16_t bbr_hptsi_segments_floor;
740 	uint16_t bbr_utter_max;
741 	uint16_t bbr_google_discount;
742 
743 };
744 
745 
746 struct socket;
747 struct tcp_bbr {
748 	/* First cache line 0x00 */
749 	int32_t(*r_substate) (struct mbuf *, struct tcphdr *,
750 	    struct socket *, struct tcpcb *, struct tcpopt *,
751 	    int32_t, int32_t, uint32_t, int32_t, int32_t);	/* Lock(a) */
752 	struct tcpcb *rc_tp;	/* The tcpcb Lock(a) */
753 	struct inpcb *rc_inp;	/* The inpcb Lock(a) */
754 	struct timeval rc_tv;
755 	uint32_t rc_pacer_started;  /* Time we started the pacer */
756 	uint16_t no_pacing_until:8, /* No pacing until N packet epochs */
757 		 ts_can_raise:1,/* TS b/w calculations can raise the bw higher */
758 		 skip_gain:1,	/* Skip the gain cycle (hardware pacing) */
759 		 gain_is_limited:1,	/* With hardware pacing we are limiting gain */
760 		 output_error_seen:1,
761 		 oerror_cnt:4,
762 		hw_pacing_set:1;	/* long enough has passed for us to start pacing */
763 	uint16_t xxx_r_ack_count;	/* During recovery count of ack's received
764 				 * that added data since output */
765 	uint16_t bbr_segs_rcvd;	/* In Segment count since we sent a ack */
766 
767 	uint8_t bbr_timer_src:4,	/* Used for debugging Lock(a) */
768 		bbr_use_rack_cheat:1,   /* Use the rack cheat */
769 		bbr_init_win_cheat:1,	/* Send full IW for TSO */
770 		bbr_attempt_hdwr_pace:1,/* Try to do hardware pacing */
771 		bbr_hdrw_pacing:1;	/* Hardware pacing is available */
772 	uint8_t bbr_hdw_pace_ena:1,	/* Does the connection allow hardware pacing to be attempted */
773 		bbr_prev_in_rec:1,	/* We were previously in recovery */
774 		pkt_conservation:1,
775 		use_policer_detection:1,
776 		xxx_bbr_hdw_pace_idx:4;	/* If hardware pacing is on, index to slot in pace tbl */
777 	uint16_t r_wanted_output:1,
778 		 rtt_valid:1,
779 		 rc_timer_first:1,
780 		 rc_output_starts_timer:1,
781 		 rc_resends_use_tso:1,
782 		 rc_all_timers_stopped:1,
783 		 rc_loss_exit:1,
784 		 rc_ack_was_delayed:1,
785 		 rc_lt_is_sampling:1,
786 		 rc_filled_pipe:1,
787 		 rc_tlp_new_data:1,
788 		 rc_hit_state_1:1,
789 		 rc_ts_valid:1,
790 		 rc_prtt_set_ts:1,
791 		 rc_is_pkt_epoch_now:1,
792 		 rc_has_collapsed:1;
793 
794 	uint8_t r_state:4,	/* Current bbr state Lock(a) */
795 	        r_agg_early_set:1,	/* Did we get called early */
796 		r_init_rtt:1,
797 		r_use_policer:1,	/* For google mode only */
798 		r_recovery_bw:1;
799 	uint8_t r_timer_override:1,	/* pacer override Lock(a)  0/1 */
800 	        rc_in_persist:1,
801 		rc_lt_use_bw:1,
802 		rc_allow_data_af_clo:1,
803 		rc_tlp_rtx_out:1,	/* A TLP is in flight  */
804 	        rc_tlp_in_progress:1,	/* a TLP timer is running needed? */
805 	        rc_use_idle_restart:1;   /* Do we restart fast after idle (persist or applim) */
806 	uint8_t rc_bbr_state:3,	/* What is the major BBR state */
807 	        rc_bbr_substate:3,	/* For probeBW state */
808 	        r_is_v6:1,
809 		rc_past_init_win:1;
810 	uint8_t rc_last_options;
811 	uint8_t rc_tlp_threshold;	/* Socket option value Lock(a) */
812 	uint8_t rc_max_rto_sec;
813 	uint8_t rc_cwnd_limited:1,	/* We are cwnd limited */
814 		rc_tmr_stopped:7;	/* What timers have been stopped  */
815 	uint8_t rc_use_google:1,
816 		rc_use_ts_limit:1,
817 		rc_ts_data_set:1,	/* We have filled a set point to determine */
818 		rc_ts_clock_set:1, 	/* We have determined the ts type */
819 		rc_ts_cant_be_used:1,	/* We determined we can't use ts values */
820 		rc_ack_is_cumack:1,
821 		rc_no_pacing:1,
822 		alloc_limit_reported:1;
823 	uint8_t rc_init_win;
824 	/* Cache line 2 0x40 */
825 	struct bbr_control r_ctl;
826 #ifdef _KERNEL
827 }       __aligned(CACHE_LINE_SIZE);
828 #else
829 };
830 #endif
831 
832 #endif
833