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[mirror_ubuntu-artful-kernel.git] / tools / perf / util / intel-pt-decoder / intel-pt-decoder.c
1 /*
2 * intel_pt_decoder.c: Intel Processor Trace support
3 * Copyright (c) 2013-2014, Intel Corporation.
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
12 * more details.
13 *
14 */
15
16 #ifndef _GNU_SOURCE
17 #define _GNU_SOURCE
18 #endif
19 #include <stdlib.h>
20 #include <stdbool.h>
21 #include <string.h>
22 #include <errno.h>
23 #include <stdint.h>
24 #include <inttypes.h>
25
26 #include "../cache.h"
27 #include "../util.h"
28
29 #include "intel-pt-insn-decoder.h"
30 #include "intel-pt-pkt-decoder.h"
31 #include "intel-pt-decoder.h"
32 #include "intel-pt-log.h"
33
34 #define INTEL_PT_BLK_SIZE 1024
35
36 #define BIT63 (((uint64_t)1 << 63))
37
38 #define INTEL_PT_RETURN 1
39
40 /* Maximum number of loops with no packets consumed i.e. stuck in a loop */
41 #define INTEL_PT_MAX_LOOPS 10000
42
43 struct intel_pt_blk {
44 struct intel_pt_blk *prev;
45 uint64_t ip[INTEL_PT_BLK_SIZE];
46 };
47
48 struct intel_pt_stack {
49 struct intel_pt_blk *blk;
50 struct intel_pt_blk *spare;
51 int pos;
52 };
53
54 enum intel_pt_pkt_state {
55 INTEL_PT_STATE_NO_PSB,
56 INTEL_PT_STATE_NO_IP,
57 INTEL_PT_STATE_ERR_RESYNC,
58 INTEL_PT_STATE_IN_SYNC,
59 INTEL_PT_STATE_TNT,
60 INTEL_PT_STATE_TIP,
61 INTEL_PT_STATE_TIP_PGD,
62 INTEL_PT_STATE_FUP,
63 INTEL_PT_STATE_FUP_NO_TIP,
64 };
65
66 #ifdef INTEL_PT_STRICT
67 #define INTEL_PT_STATE_ERR1 INTEL_PT_STATE_NO_PSB
68 #define INTEL_PT_STATE_ERR2 INTEL_PT_STATE_NO_PSB
69 #define INTEL_PT_STATE_ERR3 INTEL_PT_STATE_NO_PSB
70 #define INTEL_PT_STATE_ERR4 INTEL_PT_STATE_NO_PSB
71 #else
72 #define INTEL_PT_STATE_ERR1 (decoder->pkt_state)
73 #define INTEL_PT_STATE_ERR2 INTEL_PT_STATE_NO_IP
74 #define INTEL_PT_STATE_ERR3 INTEL_PT_STATE_ERR_RESYNC
75 #define INTEL_PT_STATE_ERR4 INTEL_PT_STATE_IN_SYNC
76 #endif
77
78 struct intel_pt_decoder {
79 int (*get_trace)(struct intel_pt_buffer *buffer, void *data);
80 int (*walk_insn)(struct intel_pt_insn *intel_pt_insn,
81 uint64_t *insn_cnt_ptr, uint64_t *ip, uint64_t to_ip,
82 uint64_t max_insn_cnt, void *data);
83 bool (*pgd_ip)(uint64_t ip, void *data);
84 void *data;
85 struct intel_pt_state state;
86 const unsigned char *buf;
87 size_t len;
88 bool return_compression;
89 bool mtc_insn;
90 bool pge;
91 bool have_tma;
92 bool have_cyc;
93 bool fixup_last_mtc;
94 uint64_t pos;
95 uint64_t last_ip;
96 uint64_t ip;
97 uint64_t cr3;
98 uint64_t timestamp;
99 uint64_t tsc_timestamp;
100 uint64_t ref_timestamp;
101 uint64_t ret_addr;
102 uint64_t ctc_timestamp;
103 uint64_t ctc_delta;
104 uint64_t cycle_cnt;
105 uint64_t cyc_ref_timestamp;
106 uint32_t last_mtc;
107 uint32_t tsc_ctc_ratio_n;
108 uint32_t tsc_ctc_ratio_d;
109 uint32_t tsc_ctc_mult;
110 uint32_t tsc_slip;
111 uint32_t ctc_rem_mask;
112 int mtc_shift;
113 struct intel_pt_stack stack;
114 enum intel_pt_pkt_state pkt_state;
115 struct intel_pt_pkt packet;
116 struct intel_pt_pkt tnt;
117 int pkt_step;
118 int pkt_len;
119 int last_packet_type;
120 unsigned int cbr;
121 unsigned int max_non_turbo_ratio;
122 double max_non_turbo_ratio_fp;
123 double cbr_cyc_to_tsc;
124 double calc_cyc_to_tsc;
125 bool have_calc_cyc_to_tsc;
126 int exec_mode;
127 unsigned int insn_bytes;
128 uint64_t period;
129 enum intel_pt_period_type period_type;
130 uint64_t tot_insn_cnt;
131 uint64_t period_insn_cnt;
132 uint64_t period_mask;
133 uint64_t period_ticks;
134 uint64_t last_masked_timestamp;
135 bool continuous_period;
136 bool overflow;
137 bool set_fup_tx_flags;
138 unsigned int fup_tx_flags;
139 unsigned int tx_flags;
140 uint64_t timestamp_insn_cnt;
141 uint64_t stuck_ip;
142 int no_progress;
143 int stuck_ip_prd;
144 int stuck_ip_cnt;
145 const unsigned char *next_buf;
146 size_t next_len;
147 unsigned char temp_buf[INTEL_PT_PKT_MAX_SZ];
148 };
149
150 static uint64_t intel_pt_lower_power_of_2(uint64_t x)
151 {
152 int i;
153
154 for (i = 0; x != 1; i++)
155 x >>= 1;
156
157 return x << i;
158 }
159
160 static void intel_pt_setup_period(struct intel_pt_decoder *decoder)
161 {
162 if (decoder->period_type == INTEL_PT_PERIOD_TICKS) {
163 uint64_t period;
164
165 period = intel_pt_lower_power_of_2(decoder->period);
166 decoder->period_mask = ~(period - 1);
167 decoder->period_ticks = period;
168 }
169 }
170
171 static uint64_t multdiv(uint64_t t, uint32_t n, uint32_t d)
172 {
173 if (!d)
174 return 0;
175 return (t / d) * n + ((t % d) * n) / d;
176 }
177
178 struct intel_pt_decoder *intel_pt_decoder_new(struct intel_pt_params *params)
179 {
180 struct intel_pt_decoder *decoder;
181
182 if (!params->get_trace || !params->walk_insn)
183 return NULL;
184
185 decoder = zalloc(sizeof(struct intel_pt_decoder));
186 if (!decoder)
187 return NULL;
188
189 decoder->get_trace = params->get_trace;
190 decoder->walk_insn = params->walk_insn;
191 decoder->pgd_ip = params->pgd_ip;
192 decoder->data = params->data;
193 decoder->return_compression = params->return_compression;
194
195 decoder->period = params->period;
196 decoder->period_type = params->period_type;
197
198 decoder->max_non_turbo_ratio = params->max_non_turbo_ratio;
199 decoder->max_non_turbo_ratio_fp = params->max_non_turbo_ratio;
200
201 intel_pt_setup_period(decoder);
202
203 decoder->mtc_shift = params->mtc_period;
204 decoder->ctc_rem_mask = (1 << decoder->mtc_shift) - 1;
205
206 decoder->tsc_ctc_ratio_n = params->tsc_ctc_ratio_n;
207 decoder->tsc_ctc_ratio_d = params->tsc_ctc_ratio_d;
208
209 if (!decoder->tsc_ctc_ratio_n)
210 decoder->tsc_ctc_ratio_d = 0;
211
212 if (decoder->tsc_ctc_ratio_d) {
213 if (!(decoder->tsc_ctc_ratio_n % decoder->tsc_ctc_ratio_d))
214 decoder->tsc_ctc_mult = decoder->tsc_ctc_ratio_n /
215 decoder->tsc_ctc_ratio_d;
216
217 /*
218 * Allow for timestamps appearing to backwards because a TSC
219 * packet has slipped past a MTC packet, so allow 2 MTC ticks
220 * or ...
221 */
222 decoder->tsc_slip = multdiv(2 << decoder->mtc_shift,
223 decoder->tsc_ctc_ratio_n,
224 decoder->tsc_ctc_ratio_d);
225 }
226 /* ... or 0x100 paranoia */
227 if (decoder->tsc_slip < 0x100)
228 decoder->tsc_slip = 0x100;
229
230 intel_pt_log("timestamp: mtc_shift %u\n", decoder->mtc_shift);
231 intel_pt_log("timestamp: tsc_ctc_ratio_n %u\n", decoder->tsc_ctc_ratio_n);
232 intel_pt_log("timestamp: tsc_ctc_ratio_d %u\n", decoder->tsc_ctc_ratio_d);
233 intel_pt_log("timestamp: tsc_ctc_mult %u\n", decoder->tsc_ctc_mult);
234 intel_pt_log("timestamp: tsc_slip %#x\n", decoder->tsc_slip);
235
236 return decoder;
237 }
238
239 static void intel_pt_pop_blk(struct intel_pt_stack *stack)
240 {
241 struct intel_pt_blk *blk = stack->blk;
242
243 stack->blk = blk->prev;
244 if (!stack->spare)
245 stack->spare = blk;
246 else
247 free(blk);
248 }
249
250 static uint64_t intel_pt_pop(struct intel_pt_stack *stack)
251 {
252 if (!stack->pos) {
253 if (!stack->blk)
254 return 0;
255 intel_pt_pop_blk(stack);
256 if (!stack->blk)
257 return 0;
258 stack->pos = INTEL_PT_BLK_SIZE;
259 }
260 return stack->blk->ip[--stack->pos];
261 }
262
263 static int intel_pt_alloc_blk(struct intel_pt_stack *stack)
264 {
265 struct intel_pt_blk *blk;
266
267 if (stack->spare) {
268 blk = stack->spare;
269 stack->spare = NULL;
270 } else {
271 blk = malloc(sizeof(struct intel_pt_blk));
272 if (!blk)
273 return -ENOMEM;
274 }
275
276 blk->prev = stack->blk;
277 stack->blk = blk;
278 stack->pos = 0;
279 return 0;
280 }
281
282 static int intel_pt_push(struct intel_pt_stack *stack, uint64_t ip)
283 {
284 int err;
285
286 if (!stack->blk || stack->pos == INTEL_PT_BLK_SIZE) {
287 err = intel_pt_alloc_blk(stack);
288 if (err)
289 return err;
290 }
291
292 stack->blk->ip[stack->pos++] = ip;
293 return 0;
294 }
295
296 static void intel_pt_clear_stack(struct intel_pt_stack *stack)
297 {
298 while (stack->blk)
299 intel_pt_pop_blk(stack);
300 stack->pos = 0;
301 }
302
303 static void intel_pt_free_stack(struct intel_pt_stack *stack)
304 {
305 intel_pt_clear_stack(stack);
306 zfree(&stack->blk);
307 zfree(&stack->spare);
308 }
309
310 void intel_pt_decoder_free(struct intel_pt_decoder *decoder)
311 {
312 intel_pt_free_stack(&decoder->stack);
313 free(decoder);
314 }
315
316 static int intel_pt_ext_err(int code)
317 {
318 switch (code) {
319 case -ENOMEM:
320 return INTEL_PT_ERR_NOMEM;
321 case -ENOSYS:
322 return INTEL_PT_ERR_INTERN;
323 case -EBADMSG:
324 return INTEL_PT_ERR_BADPKT;
325 case -ENODATA:
326 return INTEL_PT_ERR_NODATA;
327 case -EILSEQ:
328 return INTEL_PT_ERR_NOINSN;
329 case -ENOENT:
330 return INTEL_PT_ERR_MISMAT;
331 case -EOVERFLOW:
332 return INTEL_PT_ERR_OVR;
333 case -ENOSPC:
334 return INTEL_PT_ERR_LOST;
335 case -ELOOP:
336 return INTEL_PT_ERR_NELOOP;
337 default:
338 return INTEL_PT_ERR_UNK;
339 }
340 }
341
342 static const char *intel_pt_err_msgs[] = {
343 [INTEL_PT_ERR_NOMEM] = "Memory allocation failed",
344 [INTEL_PT_ERR_INTERN] = "Internal error",
345 [INTEL_PT_ERR_BADPKT] = "Bad packet",
346 [INTEL_PT_ERR_NODATA] = "No more data",
347 [INTEL_PT_ERR_NOINSN] = "Failed to get instruction",
348 [INTEL_PT_ERR_MISMAT] = "Trace doesn't match instruction",
349 [INTEL_PT_ERR_OVR] = "Overflow packet",
350 [INTEL_PT_ERR_LOST] = "Lost trace data",
351 [INTEL_PT_ERR_UNK] = "Unknown error!",
352 [INTEL_PT_ERR_NELOOP] = "Never-ending loop",
353 };
354
355 int intel_pt__strerror(int code, char *buf, size_t buflen)
356 {
357 if (code < 1 || code >= INTEL_PT_ERR_MAX)
358 code = INTEL_PT_ERR_UNK;
359 strlcpy(buf, intel_pt_err_msgs[code], buflen);
360 return 0;
361 }
362
363 static uint64_t intel_pt_calc_ip(const struct intel_pt_pkt *packet,
364 uint64_t last_ip)
365 {
366 uint64_t ip;
367
368 switch (packet->count) {
369 case 1:
370 ip = (last_ip & (uint64_t)0xffffffffffff0000ULL) |
371 packet->payload;
372 break;
373 case 2:
374 ip = (last_ip & (uint64_t)0xffffffff00000000ULL) |
375 packet->payload;
376 break;
377 case 3:
378 ip = packet->payload;
379 /* Sign-extend 6-byte ip */
380 if (ip & (uint64_t)0x800000000000ULL)
381 ip |= (uint64_t)0xffff000000000000ULL;
382 break;
383 case 4:
384 ip = (last_ip & (uint64_t)0xffff000000000000ULL) |
385 packet->payload;
386 break;
387 case 6:
388 ip = packet->payload;
389 break;
390 default:
391 return 0;
392 }
393
394 return ip;
395 }
396
397 static inline void intel_pt_set_last_ip(struct intel_pt_decoder *decoder)
398 {
399 decoder->last_ip = intel_pt_calc_ip(&decoder->packet, decoder->last_ip);
400 }
401
402 static inline void intel_pt_set_ip(struct intel_pt_decoder *decoder)
403 {
404 intel_pt_set_last_ip(decoder);
405 decoder->ip = decoder->last_ip;
406 }
407
408 static void intel_pt_decoder_log_packet(struct intel_pt_decoder *decoder)
409 {
410 intel_pt_log_packet(&decoder->packet, decoder->pkt_len, decoder->pos,
411 decoder->buf);
412 }
413
414 static int intel_pt_bug(struct intel_pt_decoder *decoder)
415 {
416 intel_pt_log("ERROR: Internal error\n");
417 decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
418 return -ENOSYS;
419 }
420
421 static inline void intel_pt_clear_tx_flags(struct intel_pt_decoder *decoder)
422 {
423 decoder->tx_flags = 0;
424 }
425
426 static inline void intel_pt_update_in_tx(struct intel_pt_decoder *decoder)
427 {
428 decoder->tx_flags = decoder->packet.payload & INTEL_PT_IN_TX;
429 }
430
431 static int intel_pt_bad_packet(struct intel_pt_decoder *decoder)
432 {
433 intel_pt_clear_tx_flags(decoder);
434 decoder->have_tma = false;
435 decoder->pkt_len = 1;
436 decoder->pkt_step = 1;
437 intel_pt_decoder_log_packet(decoder);
438 if (decoder->pkt_state != INTEL_PT_STATE_NO_PSB) {
439 intel_pt_log("ERROR: Bad packet\n");
440 decoder->pkt_state = INTEL_PT_STATE_ERR1;
441 }
442 return -EBADMSG;
443 }
444
445 static int intel_pt_get_data(struct intel_pt_decoder *decoder)
446 {
447 struct intel_pt_buffer buffer = { .buf = 0, };
448 int ret;
449
450 decoder->pkt_step = 0;
451
452 intel_pt_log("Getting more data\n");
453 ret = decoder->get_trace(&buffer, decoder->data);
454 if (ret)
455 return ret;
456 decoder->buf = buffer.buf;
457 decoder->len = buffer.len;
458 if (!decoder->len) {
459 intel_pt_log("No more data\n");
460 return -ENODATA;
461 }
462 if (!buffer.consecutive) {
463 decoder->ip = 0;
464 decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
465 decoder->ref_timestamp = buffer.ref_timestamp;
466 decoder->timestamp = 0;
467 decoder->have_tma = false;
468 decoder->state.trace_nr = buffer.trace_nr;
469 intel_pt_log("Reference timestamp 0x%" PRIx64 "\n",
470 decoder->ref_timestamp);
471 return -ENOLINK;
472 }
473
474 return 0;
475 }
476
477 static int intel_pt_get_next_data(struct intel_pt_decoder *decoder)
478 {
479 if (!decoder->next_buf)
480 return intel_pt_get_data(decoder);
481
482 decoder->buf = decoder->next_buf;
483 decoder->len = decoder->next_len;
484 decoder->next_buf = 0;
485 decoder->next_len = 0;
486 return 0;
487 }
488
489 static int intel_pt_get_split_packet(struct intel_pt_decoder *decoder)
490 {
491 unsigned char *buf = decoder->temp_buf;
492 size_t old_len, len, n;
493 int ret;
494
495 old_len = decoder->len;
496 len = decoder->len;
497 memcpy(buf, decoder->buf, len);
498
499 ret = intel_pt_get_data(decoder);
500 if (ret) {
501 decoder->pos += old_len;
502 return ret < 0 ? ret : -EINVAL;
503 }
504
505 n = INTEL_PT_PKT_MAX_SZ - len;
506 if (n > decoder->len)
507 n = decoder->len;
508 memcpy(buf + len, decoder->buf, n);
509 len += n;
510
511 ret = intel_pt_get_packet(buf, len, &decoder->packet);
512 if (ret < (int)old_len) {
513 decoder->next_buf = decoder->buf;
514 decoder->next_len = decoder->len;
515 decoder->buf = buf;
516 decoder->len = old_len;
517 return intel_pt_bad_packet(decoder);
518 }
519
520 decoder->next_buf = decoder->buf + (ret - old_len);
521 decoder->next_len = decoder->len - (ret - old_len);
522
523 decoder->buf = buf;
524 decoder->len = ret;
525
526 return ret;
527 }
528
529 struct intel_pt_pkt_info {
530 struct intel_pt_decoder *decoder;
531 struct intel_pt_pkt packet;
532 uint64_t pos;
533 int pkt_len;
534 int last_packet_type;
535 void *data;
536 };
537
538 typedef int (*intel_pt_pkt_cb_t)(struct intel_pt_pkt_info *pkt_info);
539
540 /* Lookahead packets in current buffer */
541 static int intel_pt_pkt_lookahead(struct intel_pt_decoder *decoder,
542 intel_pt_pkt_cb_t cb, void *data)
543 {
544 struct intel_pt_pkt_info pkt_info;
545 const unsigned char *buf = decoder->buf;
546 size_t len = decoder->len;
547 int ret;
548
549 pkt_info.decoder = decoder;
550 pkt_info.pos = decoder->pos;
551 pkt_info.pkt_len = decoder->pkt_step;
552 pkt_info.last_packet_type = decoder->last_packet_type;
553 pkt_info.data = data;
554
555 while (1) {
556 do {
557 pkt_info.pos += pkt_info.pkt_len;
558 buf += pkt_info.pkt_len;
559 len -= pkt_info.pkt_len;
560
561 if (!len)
562 return INTEL_PT_NEED_MORE_BYTES;
563
564 ret = intel_pt_get_packet(buf, len, &pkt_info.packet);
565 if (!ret)
566 return INTEL_PT_NEED_MORE_BYTES;
567 if (ret < 0)
568 return ret;
569
570 pkt_info.pkt_len = ret;
571 } while (pkt_info.packet.type == INTEL_PT_PAD);
572
573 ret = cb(&pkt_info);
574 if (ret)
575 return 0;
576
577 pkt_info.last_packet_type = pkt_info.packet.type;
578 }
579 }
580
581 struct intel_pt_calc_cyc_to_tsc_info {
582 uint64_t cycle_cnt;
583 unsigned int cbr;
584 uint32_t last_mtc;
585 uint64_t ctc_timestamp;
586 uint64_t ctc_delta;
587 uint64_t tsc_timestamp;
588 uint64_t timestamp;
589 bool have_tma;
590 bool fixup_last_mtc;
591 bool from_mtc;
592 double cbr_cyc_to_tsc;
593 };
594
595 /*
596 * MTC provides a 8-bit slice of CTC but the TMA packet only provides the lower
597 * 16 bits of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC
598 * provided by the TMA packet. Fix-up the last_mtc calculated from the TMA
599 * packet by copying the missing bits from the current MTC assuming the least
600 * difference between the two, and that the current MTC comes after last_mtc.
601 */
602 static void intel_pt_fixup_last_mtc(uint32_t mtc, int mtc_shift,
603 uint32_t *last_mtc)
604 {
605 uint32_t first_missing_bit = 1U << (16 - mtc_shift);
606 uint32_t mask = ~(first_missing_bit - 1);
607
608 *last_mtc |= mtc & mask;
609 if (*last_mtc >= mtc) {
610 *last_mtc -= first_missing_bit;
611 *last_mtc &= 0xff;
612 }
613 }
614
615 static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
616 {
617 struct intel_pt_decoder *decoder = pkt_info->decoder;
618 struct intel_pt_calc_cyc_to_tsc_info *data = pkt_info->data;
619 uint64_t timestamp;
620 double cyc_to_tsc;
621 unsigned int cbr;
622 uint32_t mtc, mtc_delta, ctc, fc, ctc_rem;
623
624 switch (pkt_info->packet.type) {
625 case INTEL_PT_TNT:
626 case INTEL_PT_TIP_PGE:
627 case INTEL_PT_TIP:
628 case INTEL_PT_FUP:
629 case INTEL_PT_PSB:
630 case INTEL_PT_PIP:
631 case INTEL_PT_MODE_EXEC:
632 case INTEL_PT_MODE_TSX:
633 case INTEL_PT_PSBEND:
634 case INTEL_PT_PAD:
635 case INTEL_PT_VMCS:
636 case INTEL_PT_MNT:
637 return 0;
638
639 case INTEL_PT_MTC:
640 if (!data->have_tma)
641 return 0;
642
643 mtc = pkt_info->packet.payload;
644 if (decoder->mtc_shift > 8 && data->fixup_last_mtc) {
645 data->fixup_last_mtc = false;
646 intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
647 &data->last_mtc);
648 }
649 if (mtc > data->last_mtc)
650 mtc_delta = mtc - data->last_mtc;
651 else
652 mtc_delta = mtc + 256 - data->last_mtc;
653 data->ctc_delta += mtc_delta << decoder->mtc_shift;
654 data->last_mtc = mtc;
655
656 if (decoder->tsc_ctc_mult) {
657 timestamp = data->ctc_timestamp +
658 data->ctc_delta * decoder->tsc_ctc_mult;
659 } else {
660 timestamp = data->ctc_timestamp +
661 multdiv(data->ctc_delta,
662 decoder->tsc_ctc_ratio_n,
663 decoder->tsc_ctc_ratio_d);
664 }
665
666 if (timestamp < data->timestamp)
667 return 1;
668
669 if (pkt_info->last_packet_type != INTEL_PT_CYC) {
670 data->timestamp = timestamp;
671 return 0;
672 }
673
674 break;
675
676 case INTEL_PT_TSC:
677 timestamp = pkt_info->packet.payload |
678 (data->timestamp & (0xffULL << 56));
679 if (data->from_mtc && timestamp < data->timestamp &&
680 data->timestamp - timestamp < decoder->tsc_slip)
681 return 1;
682 if (timestamp < data->timestamp)
683 timestamp += (1ULL << 56);
684 if (pkt_info->last_packet_type != INTEL_PT_CYC) {
685 if (data->from_mtc)
686 return 1;
687 data->tsc_timestamp = timestamp;
688 data->timestamp = timestamp;
689 return 0;
690 }
691 break;
692
693 case INTEL_PT_TMA:
694 if (data->from_mtc)
695 return 1;
696
697 if (!decoder->tsc_ctc_ratio_d)
698 return 0;
699
700 ctc = pkt_info->packet.payload;
701 fc = pkt_info->packet.count;
702 ctc_rem = ctc & decoder->ctc_rem_mask;
703
704 data->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
705
706 data->ctc_timestamp = data->tsc_timestamp - fc;
707 if (decoder->tsc_ctc_mult) {
708 data->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
709 } else {
710 data->ctc_timestamp -=
711 multdiv(ctc_rem, decoder->tsc_ctc_ratio_n,
712 decoder->tsc_ctc_ratio_d);
713 }
714
715 data->ctc_delta = 0;
716 data->have_tma = true;
717 data->fixup_last_mtc = true;
718
719 return 0;
720
721 case INTEL_PT_CYC:
722 data->cycle_cnt += pkt_info->packet.payload;
723 return 0;
724
725 case INTEL_PT_CBR:
726 cbr = pkt_info->packet.payload;
727 if (data->cbr && data->cbr != cbr)
728 return 1;
729 data->cbr = cbr;
730 data->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
731 return 0;
732
733 case INTEL_PT_TIP_PGD:
734 case INTEL_PT_TRACESTOP:
735 case INTEL_PT_OVF:
736 case INTEL_PT_BAD: /* Does not happen */
737 default:
738 return 1;
739 }
740
741 if (!data->cbr && decoder->cbr) {
742 data->cbr = decoder->cbr;
743 data->cbr_cyc_to_tsc = decoder->cbr_cyc_to_tsc;
744 }
745
746 if (!data->cycle_cnt)
747 return 1;
748
749 cyc_to_tsc = (double)(timestamp - decoder->timestamp) / data->cycle_cnt;
750
751 if (data->cbr && cyc_to_tsc > data->cbr_cyc_to_tsc &&
752 cyc_to_tsc / data->cbr_cyc_to_tsc > 1.25) {
753 intel_pt_log("Timestamp: calculated %g TSC ticks per cycle too big (c.f. CBR-based value %g), pos " x64_fmt "\n",
754 cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
755 return 1;
756 }
757
758 decoder->calc_cyc_to_tsc = cyc_to_tsc;
759 decoder->have_calc_cyc_to_tsc = true;
760
761 if (data->cbr) {
762 intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. CBR-based value %g, pos " x64_fmt "\n",
763 cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
764 } else {
765 intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. unknown CBR-based value, pos " x64_fmt "\n",
766 cyc_to_tsc, pkt_info->pos);
767 }
768
769 return 1;
770 }
771
772 static void intel_pt_calc_cyc_to_tsc(struct intel_pt_decoder *decoder,
773 bool from_mtc)
774 {
775 struct intel_pt_calc_cyc_to_tsc_info data = {
776 .cycle_cnt = 0,
777 .cbr = 0,
778 .last_mtc = decoder->last_mtc,
779 .ctc_timestamp = decoder->ctc_timestamp,
780 .ctc_delta = decoder->ctc_delta,
781 .tsc_timestamp = decoder->tsc_timestamp,
782 .timestamp = decoder->timestamp,
783 .have_tma = decoder->have_tma,
784 .fixup_last_mtc = decoder->fixup_last_mtc,
785 .from_mtc = from_mtc,
786 .cbr_cyc_to_tsc = 0,
787 };
788
789 intel_pt_pkt_lookahead(decoder, intel_pt_calc_cyc_cb, &data);
790 }
791
792 static int intel_pt_get_next_packet(struct intel_pt_decoder *decoder)
793 {
794 int ret;
795
796 decoder->last_packet_type = decoder->packet.type;
797
798 do {
799 decoder->pos += decoder->pkt_step;
800 decoder->buf += decoder->pkt_step;
801 decoder->len -= decoder->pkt_step;
802
803 if (!decoder->len) {
804 ret = intel_pt_get_next_data(decoder);
805 if (ret)
806 return ret;
807 }
808
809 ret = intel_pt_get_packet(decoder->buf, decoder->len,
810 &decoder->packet);
811 if (ret == INTEL_PT_NEED_MORE_BYTES &&
812 decoder->len < INTEL_PT_PKT_MAX_SZ && !decoder->next_buf) {
813 ret = intel_pt_get_split_packet(decoder);
814 if (ret < 0)
815 return ret;
816 }
817 if (ret <= 0)
818 return intel_pt_bad_packet(decoder);
819
820 decoder->pkt_len = ret;
821 decoder->pkt_step = ret;
822 intel_pt_decoder_log_packet(decoder);
823 } while (decoder->packet.type == INTEL_PT_PAD);
824
825 return 0;
826 }
827
828 static uint64_t intel_pt_next_period(struct intel_pt_decoder *decoder)
829 {
830 uint64_t timestamp, masked_timestamp;
831
832 timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
833 masked_timestamp = timestamp & decoder->period_mask;
834 if (decoder->continuous_period) {
835 if (masked_timestamp != decoder->last_masked_timestamp)
836 return 1;
837 } else {
838 timestamp += 1;
839 masked_timestamp = timestamp & decoder->period_mask;
840 if (masked_timestamp != decoder->last_masked_timestamp) {
841 decoder->last_masked_timestamp = masked_timestamp;
842 decoder->continuous_period = true;
843 }
844 }
845 return decoder->period_ticks - (timestamp - masked_timestamp);
846 }
847
848 static uint64_t intel_pt_next_sample(struct intel_pt_decoder *decoder)
849 {
850 switch (decoder->period_type) {
851 case INTEL_PT_PERIOD_INSTRUCTIONS:
852 return decoder->period - decoder->period_insn_cnt;
853 case INTEL_PT_PERIOD_TICKS:
854 return intel_pt_next_period(decoder);
855 case INTEL_PT_PERIOD_NONE:
856 case INTEL_PT_PERIOD_MTC:
857 default:
858 return 0;
859 }
860 }
861
862 static void intel_pt_sample_insn(struct intel_pt_decoder *decoder)
863 {
864 uint64_t timestamp, masked_timestamp;
865
866 switch (decoder->period_type) {
867 case INTEL_PT_PERIOD_INSTRUCTIONS:
868 decoder->period_insn_cnt = 0;
869 break;
870 case INTEL_PT_PERIOD_TICKS:
871 timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
872 masked_timestamp = timestamp & decoder->period_mask;
873 decoder->last_masked_timestamp = masked_timestamp;
874 break;
875 case INTEL_PT_PERIOD_NONE:
876 case INTEL_PT_PERIOD_MTC:
877 default:
878 break;
879 }
880
881 decoder->state.type |= INTEL_PT_INSTRUCTION;
882 }
883
884 static int intel_pt_walk_insn(struct intel_pt_decoder *decoder,
885 struct intel_pt_insn *intel_pt_insn, uint64_t ip)
886 {
887 uint64_t max_insn_cnt, insn_cnt = 0;
888 int err;
889
890 if (!decoder->mtc_insn)
891 decoder->mtc_insn = true;
892
893 max_insn_cnt = intel_pt_next_sample(decoder);
894
895 err = decoder->walk_insn(intel_pt_insn, &insn_cnt, &decoder->ip, ip,
896 max_insn_cnt, decoder->data);
897
898 decoder->tot_insn_cnt += insn_cnt;
899 decoder->timestamp_insn_cnt += insn_cnt;
900 decoder->period_insn_cnt += insn_cnt;
901
902 if (err) {
903 decoder->no_progress = 0;
904 decoder->pkt_state = INTEL_PT_STATE_ERR2;
905 intel_pt_log_at("ERROR: Failed to get instruction",
906 decoder->ip);
907 if (err == -ENOENT)
908 return -ENOLINK;
909 return -EILSEQ;
910 }
911
912 if (ip && decoder->ip == ip) {
913 err = -EAGAIN;
914 goto out;
915 }
916
917 if (max_insn_cnt && insn_cnt >= max_insn_cnt)
918 intel_pt_sample_insn(decoder);
919
920 if (intel_pt_insn->branch == INTEL_PT_BR_NO_BRANCH) {
921 decoder->state.type = INTEL_PT_INSTRUCTION;
922 decoder->state.from_ip = decoder->ip;
923 decoder->state.to_ip = 0;
924 decoder->ip += intel_pt_insn->length;
925 err = INTEL_PT_RETURN;
926 goto out;
927 }
928
929 if (intel_pt_insn->op == INTEL_PT_OP_CALL) {
930 /* Zero-length calls are excluded */
931 if (intel_pt_insn->branch != INTEL_PT_BR_UNCONDITIONAL ||
932 intel_pt_insn->rel) {
933 err = intel_pt_push(&decoder->stack, decoder->ip +
934 intel_pt_insn->length);
935 if (err)
936 goto out;
937 }
938 } else if (intel_pt_insn->op == INTEL_PT_OP_RET) {
939 decoder->ret_addr = intel_pt_pop(&decoder->stack);
940 }
941
942 if (intel_pt_insn->branch == INTEL_PT_BR_UNCONDITIONAL) {
943 int cnt = decoder->no_progress++;
944
945 decoder->state.from_ip = decoder->ip;
946 decoder->ip += intel_pt_insn->length +
947 intel_pt_insn->rel;
948 decoder->state.to_ip = decoder->ip;
949 err = INTEL_PT_RETURN;
950
951 /*
952 * Check for being stuck in a loop. This can happen if a
953 * decoder error results in the decoder erroneously setting the
954 * ip to an address that is itself in an infinite loop that
955 * consumes no packets. When that happens, there must be an
956 * unconditional branch.
957 */
958 if (cnt) {
959 if (cnt == 1) {
960 decoder->stuck_ip = decoder->state.to_ip;
961 decoder->stuck_ip_prd = 1;
962 decoder->stuck_ip_cnt = 1;
963 } else if (cnt > INTEL_PT_MAX_LOOPS ||
964 decoder->state.to_ip == decoder->stuck_ip) {
965 intel_pt_log_at("ERROR: Never-ending loop",
966 decoder->state.to_ip);
967 decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
968 err = -ELOOP;
969 goto out;
970 } else if (!--decoder->stuck_ip_cnt) {
971 decoder->stuck_ip_prd += 1;
972 decoder->stuck_ip_cnt = decoder->stuck_ip_prd;
973 decoder->stuck_ip = decoder->state.to_ip;
974 }
975 }
976 goto out_no_progress;
977 }
978 out:
979 decoder->no_progress = 0;
980 out_no_progress:
981 decoder->state.insn_op = intel_pt_insn->op;
982 decoder->state.insn_len = intel_pt_insn->length;
983 memcpy(decoder->state.insn, intel_pt_insn->buf,
984 INTEL_PT_INSN_BUF_SZ);
985
986 if (decoder->tx_flags & INTEL_PT_IN_TX)
987 decoder->state.flags |= INTEL_PT_IN_TX;
988
989 return err;
990 }
991
992 static int intel_pt_walk_fup(struct intel_pt_decoder *decoder)
993 {
994 struct intel_pt_insn intel_pt_insn;
995 uint64_t ip;
996 int err;
997
998 ip = decoder->last_ip;
999
1000 while (1) {
1001 err = intel_pt_walk_insn(decoder, &intel_pt_insn, ip);
1002 if (err == INTEL_PT_RETURN)
1003 return 0;
1004 if (err == -EAGAIN) {
1005 if (decoder->set_fup_tx_flags) {
1006 decoder->set_fup_tx_flags = false;
1007 decoder->tx_flags = decoder->fup_tx_flags;
1008 decoder->state.type = INTEL_PT_TRANSACTION;
1009 decoder->state.from_ip = decoder->ip;
1010 decoder->state.to_ip = 0;
1011 decoder->state.flags = decoder->fup_tx_flags;
1012 return 0;
1013 }
1014 return err;
1015 }
1016 decoder->set_fup_tx_flags = false;
1017 if (err)
1018 return err;
1019
1020 if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1021 intel_pt_log_at("ERROR: Unexpected indirect branch",
1022 decoder->ip);
1023 decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1024 return -ENOENT;
1025 }
1026
1027 if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1028 intel_pt_log_at("ERROR: Unexpected conditional branch",
1029 decoder->ip);
1030 decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1031 return -ENOENT;
1032 }
1033
1034 intel_pt_bug(decoder);
1035 }
1036 }
1037
1038 static int intel_pt_walk_tip(struct intel_pt_decoder *decoder)
1039 {
1040 struct intel_pt_insn intel_pt_insn;
1041 int err;
1042
1043 err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1044 if (err == INTEL_PT_RETURN &&
1045 decoder->pgd_ip &&
1046 decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1047 (decoder->state.type & INTEL_PT_BRANCH) &&
1048 decoder->pgd_ip(decoder->state.to_ip, decoder->data)) {
1049 /* Unconditional branch leaving filter region */
1050 decoder->no_progress = 0;
1051 decoder->pge = false;
1052 decoder->continuous_period = false;
1053 decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1054 decoder->state.to_ip = 0;
1055 return 0;
1056 }
1057 if (err == INTEL_PT_RETURN)
1058 return 0;
1059 if (err)
1060 return err;
1061
1062 if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1063 if (decoder->pkt_state == INTEL_PT_STATE_TIP_PGD) {
1064 decoder->pge = false;
1065 decoder->continuous_period = false;
1066 decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1067 decoder->state.from_ip = decoder->ip;
1068 decoder->state.to_ip = 0;
1069 if (decoder->packet.count != 0)
1070 decoder->ip = decoder->last_ip;
1071 } else {
1072 decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1073 decoder->state.from_ip = decoder->ip;
1074 if (decoder->packet.count == 0) {
1075 decoder->state.to_ip = 0;
1076 } else {
1077 decoder->state.to_ip = decoder->last_ip;
1078 decoder->ip = decoder->last_ip;
1079 }
1080 }
1081 return 0;
1082 }
1083
1084 if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1085 uint64_t to_ip = decoder->ip + intel_pt_insn.length +
1086 intel_pt_insn.rel;
1087
1088 if (decoder->pgd_ip &&
1089 decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1090 decoder->pgd_ip(to_ip, decoder->data)) {
1091 /* Conditional branch leaving filter region */
1092 decoder->pge = false;
1093 decoder->continuous_period = false;
1094 decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1095 decoder->ip = to_ip;
1096 decoder->state.from_ip = decoder->ip;
1097 decoder->state.to_ip = 0;
1098 return 0;
1099 }
1100 intel_pt_log_at("ERROR: Conditional branch when expecting indirect branch",
1101 decoder->ip);
1102 decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1103 return -ENOENT;
1104 }
1105
1106 return intel_pt_bug(decoder);
1107 }
1108
1109 static int intel_pt_walk_tnt(struct intel_pt_decoder *decoder)
1110 {
1111 struct intel_pt_insn intel_pt_insn;
1112 int err;
1113
1114 while (1) {
1115 err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1116 if (err == INTEL_PT_RETURN)
1117 return 0;
1118 if (err)
1119 return err;
1120
1121 if (intel_pt_insn.op == INTEL_PT_OP_RET) {
1122 if (!decoder->return_compression) {
1123 intel_pt_log_at("ERROR: RET when expecting conditional branch",
1124 decoder->ip);
1125 decoder->pkt_state = INTEL_PT_STATE_ERR3;
1126 return -ENOENT;
1127 }
1128 if (!decoder->ret_addr) {
1129 intel_pt_log_at("ERROR: Bad RET compression (stack empty)",
1130 decoder->ip);
1131 decoder->pkt_state = INTEL_PT_STATE_ERR3;
1132 return -ENOENT;
1133 }
1134 if (!(decoder->tnt.payload & BIT63)) {
1135 intel_pt_log_at("ERROR: Bad RET compression (TNT=N)",
1136 decoder->ip);
1137 decoder->pkt_state = INTEL_PT_STATE_ERR3;
1138 return -ENOENT;
1139 }
1140 decoder->tnt.count -= 1;
1141 if (!decoder->tnt.count)
1142 decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1143 decoder->tnt.payload <<= 1;
1144 decoder->state.from_ip = decoder->ip;
1145 decoder->ip = decoder->ret_addr;
1146 decoder->state.to_ip = decoder->ip;
1147 return 0;
1148 }
1149
1150 if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1151 /* Handle deferred TIPs */
1152 err = intel_pt_get_next_packet(decoder);
1153 if (err)
1154 return err;
1155 if (decoder->packet.type != INTEL_PT_TIP ||
1156 decoder->packet.count == 0) {
1157 intel_pt_log_at("ERROR: Missing deferred TIP for indirect branch",
1158 decoder->ip);
1159 decoder->pkt_state = INTEL_PT_STATE_ERR3;
1160 decoder->pkt_step = 0;
1161 return -ENOENT;
1162 }
1163 intel_pt_set_last_ip(decoder);
1164 decoder->state.from_ip = decoder->ip;
1165 decoder->state.to_ip = decoder->last_ip;
1166 decoder->ip = decoder->last_ip;
1167 return 0;
1168 }
1169
1170 if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1171 decoder->tnt.count -= 1;
1172 if (!decoder->tnt.count)
1173 decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1174 if (decoder->tnt.payload & BIT63) {
1175 decoder->tnt.payload <<= 1;
1176 decoder->state.from_ip = decoder->ip;
1177 decoder->ip += intel_pt_insn.length +
1178 intel_pt_insn.rel;
1179 decoder->state.to_ip = decoder->ip;
1180 return 0;
1181 }
1182 /* Instruction sample for a non-taken branch */
1183 if (decoder->state.type & INTEL_PT_INSTRUCTION) {
1184 decoder->tnt.payload <<= 1;
1185 decoder->state.type = INTEL_PT_INSTRUCTION;
1186 decoder->state.from_ip = decoder->ip;
1187 decoder->state.to_ip = 0;
1188 decoder->ip += intel_pt_insn.length;
1189 return 0;
1190 }
1191 decoder->ip += intel_pt_insn.length;
1192 if (!decoder->tnt.count)
1193 return -EAGAIN;
1194 decoder->tnt.payload <<= 1;
1195 continue;
1196 }
1197
1198 return intel_pt_bug(decoder);
1199 }
1200 }
1201
1202 static int intel_pt_mode_tsx(struct intel_pt_decoder *decoder, bool *no_tip)
1203 {
1204 unsigned int fup_tx_flags;
1205 int err;
1206
1207 fup_tx_flags = decoder->packet.payload &
1208 (INTEL_PT_IN_TX | INTEL_PT_ABORT_TX);
1209 err = intel_pt_get_next_packet(decoder);
1210 if (err)
1211 return err;
1212 if (decoder->packet.type == INTEL_PT_FUP) {
1213 decoder->fup_tx_flags = fup_tx_flags;
1214 decoder->set_fup_tx_flags = true;
1215 if (!(decoder->fup_tx_flags & INTEL_PT_ABORT_TX))
1216 *no_tip = true;
1217 } else {
1218 intel_pt_log_at("ERROR: Missing FUP after MODE.TSX",
1219 decoder->pos);
1220 intel_pt_update_in_tx(decoder);
1221 }
1222 return 0;
1223 }
1224
1225 static void intel_pt_calc_tsc_timestamp(struct intel_pt_decoder *decoder)
1226 {
1227 uint64_t timestamp;
1228
1229 decoder->have_tma = false;
1230
1231 if (decoder->ref_timestamp) {
1232 timestamp = decoder->packet.payload |
1233 (decoder->ref_timestamp & (0xffULL << 56));
1234 if (timestamp < decoder->ref_timestamp) {
1235 if (decoder->ref_timestamp - timestamp > (1ULL << 55))
1236 timestamp += (1ULL << 56);
1237 } else {
1238 if (timestamp - decoder->ref_timestamp > (1ULL << 55))
1239 timestamp -= (1ULL << 56);
1240 }
1241 decoder->tsc_timestamp = timestamp;
1242 decoder->timestamp = timestamp;
1243 decoder->ref_timestamp = 0;
1244 decoder->timestamp_insn_cnt = 0;
1245 } else if (decoder->timestamp) {
1246 timestamp = decoder->packet.payload |
1247 (decoder->timestamp & (0xffULL << 56));
1248 decoder->tsc_timestamp = timestamp;
1249 if (timestamp < decoder->timestamp &&
1250 decoder->timestamp - timestamp < decoder->tsc_slip) {
1251 intel_pt_log_to("Suppressing backwards timestamp",
1252 timestamp);
1253 timestamp = decoder->timestamp;
1254 }
1255 if (timestamp < decoder->timestamp) {
1256 intel_pt_log_to("Wraparound timestamp", timestamp);
1257 timestamp += (1ULL << 56);
1258 decoder->tsc_timestamp = timestamp;
1259 }
1260 decoder->timestamp = timestamp;
1261 decoder->timestamp_insn_cnt = 0;
1262 }
1263
1264 if (decoder->last_packet_type == INTEL_PT_CYC) {
1265 decoder->cyc_ref_timestamp = decoder->timestamp;
1266 decoder->cycle_cnt = 0;
1267 decoder->have_calc_cyc_to_tsc = false;
1268 intel_pt_calc_cyc_to_tsc(decoder, false);
1269 }
1270
1271 intel_pt_log_to("Setting timestamp", decoder->timestamp);
1272 }
1273
1274 static int intel_pt_overflow(struct intel_pt_decoder *decoder)
1275 {
1276 intel_pt_log("ERROR: Buffer overflow\n");
1277 intel_pt_clear_tx_flags(decoder);
1278 decoder->have_tma = false;
1279 decoder->cbr = 0;
1280 decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1281 decoder->overflow = true;
1282 return -EOVERFLOW;
1283 }
1284
1285 static void intel_pt_calc_tma(struct intel_pt_decoder *decoder)
1286 {
1287 uint32_t ctc = decoder->packet.payload;
1288 uint32_t fc = decoder->packet.count;
1289 uint32_t ctc_rem = ctc & decoder->ctc_rem_mask;
1290
1291 if (!decoder->tsc_ctc_ratio_d)
1292 return;
1293
1294 decoder->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
1295 decoder->ctc_timestamp = decoder->tsc_timestamp - fc;
1296 if (decoder->tsc_ctc_mult) {
1297 decoder->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
1298 } else {
1299 decoder->ctc_timestamp -= multdiv(ctc_rem,
1300 decoder->tsc_ctc_ratio_n,
1301 decoder->tsc_ctc_ratio_d);
1302 }
1303 decoder->ctc_delta = 0;
1304 decoder->have_tma = true;
1305 decoder->fixup_last_mtc = true;
1306 intel_pt_log("CTC timestamp " x64_fmt " last MTC %#x CTC rem %#x\n",
1307 decoder->ctc_timestamp, decoder->last_mtc, ctc_rem);
1308 }
1309
1310 static void intel_pt_calc_mtc_timestamp(struct intel_pt_decoder *decoder)
1311 {
1312 uint64_t timestamp;
1313 uint32_t mtc, mtc_delta;
1314
1315 if (!decoder->have_tma)
1316 return;
1317
1318 mtc = decoder->packet.payload;
1319
1320 if (decoder->mtc_shift > 8 && decoder->fixup_last_mtc) {
1321 decoder->fixup_last_mtc = false;
1322 intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
1323 &decoder->last_mtc);
1324 }
1325
1326 if (mtc > decoder->last_mtc)
1327 mtc_delta = mtc - decoder->last_mtc;
1328 else
1329 mtc_delta = mtc + 256 - decoder->last_mtc;
1330
1331 decoder->ctc_delta += mtc_delta << decoder->mtc_shift;
1332
1333 if (decoder->tsc_ctc_mult) {
1334 timestamp = decoder->ctc_timestamp +
1335 decoder->ctc_delta * decoder->tsc_ctc_mult;
1336 } else {
1337 timestamp = decoder->ctc_timestamp +
1338 multdiv(decoder->ctc_delta,
1339 decoder->tsc_ctc_ratio_n,
1340 decoder->tsc_ctc_ratio_d);
1341 }
1342
1343 if (timestamp < decoder->timestamp)
1344 intel_pt_log("Suppressing MTC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1345 timestamp, decoder->timestamp);
1346 else
1347 decoder->timestamp = timestamp;
1348
1349 decoder->timestamp_insn_cnt = 0;
1350 decoder->last_mtc = mtc;
1351
1352 if (decoder->last_packet_type == INTEL_PT_CYC) {
1353 decoder->cyc_ref_timestamp = decoder->timestamp;
1354 decoder->cycle_cnt = 0;
1355 decoder->have_calc_cyc_to_tsc = false;
1356 intel_pt_calc_cyc_to_tsc(decoder, true);
1357 }
1358 }
1359
1360 static void intel_pt_calc_cbr(struct intel_pt_decoder *decoder)
1361 {
1362 unsigned int cbr = decoder->packet.payload;
1363
1364 if (decoder->cbr == cbr)
1365 return;
1366
1367 decoder->cbr = cbr;
1368 decoder->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
1369 }
1370
1371 static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder)
1372 {
1373 uint64_t timestamp = decoder->cyc_ref_timestamp;
1374
1375 decoder->have_cyc = true;
1376
1377 decoder->cycle_cnt += decoder->packet.payload;
1378
1379 if (!decoder->cyc_ref_timestamp)
1380 return;
1381
1382 if (decoder->have_calc_cyc_to_tsc)
1383 timestamp += decoder->cycle_cnt * decoder->calc_cyc_to_tsc;
1384 else if (decoder->cbr)
1385 timestamp += decoder->cycle_cnt * decoder->cbr_cyc_to_tsc;
1386 else
1387 return;
1388
1389 if (timestamp < decoder->timestamp)
1390 intel_pt_log("Suppressing CYC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1391 timestamp, decoder->timestamp);
1392 else
1393 decoder->timestamp = timestamp;
1394
1395 decoder->timestamp_insn_cnt = 0;
1396 }
1397
1398 /* Walk PSB+ packets when already in sync. */
1399 static int intel_pt_walk_psbend(struct intel_pt_decoder *decoder)
1400 {
1401 int err;
1402
1403 while (1) {
1404 err = intel_pt_get_next_packet(decoder);
1405 if (err)
1406 return err;
1407
1408 switch (decoder->packet.type) {
1409 case INTEL_PT_PSBEND:
1410 return 0;
1411
1412 case INTEL_PT_TIP_PGD:
1413 case INTEL_PT_TIP_PGE:
1414 case INTEL_PT_TIP:
1415 case INTEL_PT_TNT:
1416 case INTEL_PT_TRACESTOP:
1417 case INTEL_PT_BAD:
1418 case INTEL_PT_PSB:
1419 decoder->have_tma = false;
1420 intel_pt_log("ERROR: Unexpected packet\n");
1421 return -EAGAIN;
1422
1423 case INTEL_PT_OVF:
1424 return intel_pt_overflow(decoder);
1425
1426 case INTEL_PT_TSC:
1427 intel_pt_calc_tsc_timestamp(decoder);
1428 break;
1429
1430 case INTEL_PT_TMA:
1431 intel_pt_calc_tma(decoder);
1432 break;
1433
1434 case INTEL_PT_CBR:
1435 intel_pt_calc_cbr(decoder);
1436 break;
1437
1438 case INTEL_PT_MODE_EXEC:
1439 decoder->exec_mode = decoder->packet.payload;
1440 break;
1441
1442 case INTEL_PT_PIP:
1443 decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1444 break;
1445
1446 case INTEL_PT_FUP:
1447 decoder->pge = true;
1448 intel_pt_set_last_ip(decoder);
1449 break;
1450
1451 case INTEL_PT_MODE_TSX:
1452 intel_pt_update_in_tx(decoder);
1453 break;
1454
1455 case INTEL_PT_MTC:
1456 intel_pt_calc_mtc_timestamp(decoder);
1457 if (decoder->period_type == INTEL_PT_PERIOD_MTC)
1458 decoder->state.type |= INTEL_PT_INSTRUCTION;
1459 break;
1460
1461 case INTEL_PT_CYC:
1462 case INTEL_PT_VMCS:
1463 case INTEL_PT_MNT:
1464 case INTEL_PT_PAD:
1465 default:
1466 break;
1467 }
1468 }
1469 }
1470
1471 static int intel_pt_walk_fup_tip(struct intel_pt_decoder *decoder)
1472 {
1473 int err;
1474
1475 if (decoder->tx_flags & INTEL_PT_ABORT_TX) {
1476 decoder->tx_flags = 0;
1477 decoder->state.flags &= ~INTEL_PT_IN_TX;
1478 decoder->state.flags |= INTEL_PT_ABORT_TX;
1479 } else {
1480 decoder->state.flags |= INTEL_PT_ASYNC;
1481 }
1482
1483 while (1) {
1484 err = intel_pt_get_next_packet(decoder);
1485 if (err)
1486 return err;
1487
1488 switch (decoder->packet.type) {
1489 case INTEL_PT_TNT:
1490 case INTEL_PT_FUP:
1491 case INTEL_PT_TRACESTOP:
1492 case INTEL_PT_PSB:
1493 case INTEL_PT_TSC:
1494 case INTEL_PT_TMA:
1495 case INTEL_PT_CBR:
1496 case INTEL_PT_MODE_TSX:
1497 case INTEL_PT_BAD:
1498 case INTEL_PT_PSBEND:
1499 intel_pt_log("ERROR: Missing TIP after FUP\n");
1500 decoder->pkt_state = INTEL_PT_STATE_ERR3;
1501 return -ENOENT;
1502
1503 case INTEL_PT_OVF:
1504 return intel_pt_overflow(decoder);
1505
1506 case INTEL_PT_TIP_PGD:
1507 decoder->state.from_ip = decoder->ip;
1508 decoder->state.to_ip = 0;
1509 if (decoder->packet.count != 0) {
1510 intel_pt_set_ip(decoder);
1511 intel_pt_log("Omitting PGD ip " x64_fmt "\n",
1512 decoder->ip);
1513 }
1514 decoder->pge = false;
1515 decoder->continuous_period = false;
1516 return 0;
1517
1518 case INTEL_PT_TIP_PGE:
1519 decoder->pge = true;
1520 intel_pt_log("Omitting PGE ip " x64_fmt "\n",
1521 decoder->ip);
1522 decoder->state.from_ip = 0;
1523 if (decoder->packet.count == 0) {
1524 decoder->state.to_ip = 0;
1525 } else {
1526 intel_pt_set_ip(decoder);
1527 decoder->state.to_ip = decoder->ip;
1528 }
1529 return 0;
1530
1531 case INTEL_PT_TIP:
1532 decoder->state.from_ip = decoder->ip;
1533 if (decoder->packet.count == 0) {
1534 decoder->state.to_ip = 0;
1535 } else {
1536 intel_pt_set_ip(decoder);
1537 decoder->state.to_ip = decoder->ip;
1538 }
1539 return 0;
1540
1541 case INTEL_PT_PIP:
1542 decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1543 break;
1544
1545 case INTEL_PT_MTC:
1546 intel_pt_calc_mtc_timestamp(decoder);
1547 if (decoder->period_type == INTEL_PT_PERIOD_MTC)
1548 decoder->state.type |= INTEL_PT_INSTRUCTION;
1549 break;
1550
1551 case INTEL_PT_CYC:
1552 intel_pt_calc_cyc_timestamp(decoder);
1553 break;
1554
1555 case INTEL_PT_MODE_EXEC:
1556 decoder->exec_mode = decoder->packet.payload;
1557 break;
1558
1559 case INTEL_PT_VMCS:
1560 case INTEL_PT_MNT:
1561 case INTEL_PT_PAD:
1562 break;
1563
1564 default:
1565 return intel_pt_bug(decoder);
1566 }
1567 }
1568 }
1569
1570 static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
1571 {
1572 bool no_tip = false;
1573 int err;
1574
1575 while (1) {
1576 err = intel_pt_get_next_packet(decoder);
1577 if (err)
1578 return err;
1579 next:
1580 switch (decoder->packet.type) {
1581 case INTEL_PT_TNT:
1582 if (!decoder->packet.count)
1583 break;
1584 decoder->tnt = decoder->packet;
1585 decoder->pkt_state = INTEL_PT_STATE_TNT;
1586 err = intel_pt_walk_tnt(decoder);
1587 if (err == -EAGAIN)
1588 break;
1589 return err;
1590
1591 case INTEL_PT_TIP_PGD:
1592 if (decoder->packet.count != 0)
1593 intel_pt_set_last_ip(decoder);
1594 decoder->pkt_state = INTEL_PT_STATE_TIP_PGD;
1595 return intel_pt_walk_tip(decoder);
1596
1597 case INTEL_PT_TIP_PGE: {
1598 decoder->pge = true;
1599 if (decoder->packet.count == 0) {
1600 intel_pt_log_at("Skipping zero TIP.PGE",
1601 decoder->pos);
1602 break;
1603 }
1604 intel_pt_set_ip(decoder);
1605 decoder->state.from_ip = 0;
1606 decoder->state.to_ip = decoder->ip;
1607 return 0;
1608 }
1609
1610 case INTEL_PT_OVF:
1611 return intel_pt_overflow(decoder);
1612
1613 case INTEL_PT_TIP:
1614 if (decoder->packet.count != 0)
1615 intel_pt_set_last_ip(decoder);
1616 decoder->pkt_state = INTEL_PT_STATE_TIP;
1617 return intel_pt_walk_tip(decoder);
1618
1619 case INTEL_PT_FUP:
1620 if (decoder->packet.count == 0) {
1621 intel_pt_log_at("Skipping zero FUP",
1622 decoder->pos);
1623 no_tip = false;
1624 break;
1625 }
1626 intel_pt_set_last_ip(decoder);
1627 err = intel_pt_walk_fup(decoder);
1628 if (err != -EAGAIN) {
1629 if (err)
1630 return err;
1631 if (no_tip)
1632 decoder->pkt_state =
1633 INTEL_PT_STATE_FUP_NO_TIP;
1634 else
1635 decoder->pkt_state = INTEL_PT_STATE_FUP;
1636 return 0;
1637 }
1638 if (no_tip) {
1639 no_tip = false;
1640 break;
1641 }
1642 return intel_pt_walk_fup_tip(decoder);
1643
1644 case INTEL_PT_TRACESTOP:
1645 decoder->pge = false;
1646 decoder->continuous_period = false;
1647 intel_pt_clear_tx_flags(decoder);
1648 decoder->have_tma = false;
1649 break;
1650
1651 case INTEL_PT_PSB:
1652 intel_pt_clear_stack(&decoder->stack);
1653 err = intel_pt_walk_psbend(decoder);
1654 if (err == -EAGAIN)
1655 goto next;
1656 if (err)
1657 return err;
1658 break;
1659
1660 case INTEL_PT_PIP:
1661 decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1662 break;
1663
1664 case INTEL_PT_MTC:
1665 intel_pt_calc_mtc_timestamp(decoder);
1666 if (decoder->period_type != INTEL_PT_PERIOD_MTC)
1667 break;
1668 /*
1669 * Ensure that there has been an instruction since the
1670 * last MTC.
1671 */
1672 if (!decoder->mtc_insn)
1673 break;
1674 decoder->mtc_insn = false;
1675 /* Ensure that there is a timestamp */
1676 if (!decoder->timestamp)
1677 break;
1678 decoder->state.type = INTEL_PT_INSTRUCTION;
1679 decoder->state.from_ip = decoder->ip;
1680 decoder->state.to_ip = 0;
1681 decoder->mtc_insn = false;
1682 return 0;
1683
1684 case INTEL_PT_TSC:
1685 intel_pt_calc_tsc_timestamp(decoder);
1686 break;
1687
1688 case INTEL_PT_TMA:
1689 intel_pt_calc_tma(decoder);
1690 break;
1691
1692 case INTEL_PT_CYC:
1693 intel_pt_calc_cyc_timestamp(decoder);
1694 break;
1695
1696 case INTEL_PT_CBR:
1697 intel_pt_calc_cbr(decoder);
1698 break;
1699
1700 case INTEL_PT_MODE_EXEC:
1701 decoder->exec_mode = decoder->packet.payload;
1702 break;
1703
1704 case INTEL_PT_MODE_TSX:
1705 /* MODE_TSX need not be followed by FUP */
1706 if (!decoder->pge) {
1707 intel_pt_update_in_tx(decoder);
1708 break;
1709 }
1710 err = intel_pt_mode_tsx(decoder, &no_tip);
1711 if (err)
1712 return err;
1713 goto next;
1714
1715 case INTEL_PT_BAD: /* Does not happen */
1716 return intel_pt_bug(decoder);
1717
1718 case INTEL_PT_PSBEND:
1719 case INTEL_PT_VMCS:
1720 case INTEL_PT_MNT:
1721 case INTEL_PT_PAD:
1722 break;
1723
1724 default:
1725 return intel_pt_bug(decoder);
1726 }
1727 }
1728 }
1729
1730 static inline bool intel_pt_have_ip(struct intel_pt_decoder *decoder)
1731 {
1732 return decoder->last_ip || decoder->packet.count == 0 ||
1733 decoder->packet.count == 3 || decoder->packet.count == 6;
1734 }
1735
1736 /* Walk PSB+ packets to get in sync. */
1737 static int intel_pt_walk_psb(struct intel_pt_decoder *decoder)
1738 {
1739 int err;
1740
1741 while (1) {
1742 err = intel_pt_get_next_packet(decoder);
1743 if (err)
1744 return err;
1745
1746 switch (decoder->packet.type) {
1747 case INTEL_PT_TIP_PGD:
1748 decoder->continuous_period = false;
1749 case INTEL_PT_TIP_PGE:
1750 case INTEL_PT_TIP:
1751 intel_pt_log("ERROR: Unexpected packet\n");
1752 return -ENOENT;
1753
1754 case INTEL_PT_FUP:
1755 decoder->pge = true;
1756 if (intel_pt_have_ip(decoder)) {
1757 uint64_t current_ip = decoder->ip;
1758
1759 intel_pt_set_ip(decoder);
1760 if (current_ip)
1761 intel_pt_log_to("Setting IP",
1762 decoder->ip);
1763 }
1764 break;
1765
1766 case INTEL_PT_MTC:
1767 intel_pt_calc_mtc_timestamp(decoder);
1768 break;
1769
1770 case INTEL_PT_TSC:
1771 intel_pt_calc_tsc_timestamp(decoder);
1772 break;
1773
1774 case INTEL_PT_TMA:
1775 intel_pt_calc_tma(decoder);
1776 break;
1777
1778 case INTEL_PT_CYC:
1779 intel_pt_calc_cyc_timestamp(decoder);
1780 break;
1781
1782 case INTEL_PT_CBR:
1783 intel_pt_calc_cbr(decoder);
1784 break;
1785
1786 case INTEL_PT_PIP:
1787 decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1788 break;
1789
1790 case INTEL_PT_MODE_EXEC:
1791 decoder->exec_mode = decoder->packet.payload;
1792 break;
1793
1794 case INTEL_PT_MODE_TSX:
1795 intel_pt_update_in_tx(decoder);
1796 break;
1797
1798 case INTEL_PT_TRACESTOP:
1799 decoder->pge = false;
1800 decoder->continuous_period = false;
1801 intel_pt_clear_tx_flags(decoder);
1802 case INTEL_PT_TNT:
1803 decoder->have_tma = false;
1804 intel_pt_log("ERROR: Unexpected packet\n");
1805 if (decoder->ip)
1806 decoder->pkt_state = INTEL_PT_STATE_ERR4;
1807 else
1808 decoder->pkt_state = INTEL_PT_STATE_ERR3;
1809 return -ENOENT;
1810
1811 case INTEL_PT_BAD: /* Does not happen */
1812 return intel_pt_bug(decoder);
1813
1814 case INTEL_PT_OVF:
1815 return intel_pt_overflow(decoder);
1816
1817 case INTEL_PT_PSBEND:
1818 return 0;
1819
1820 case INTEL_PT_PSB:
1821 case INTEL_PT_VMCS:
1822 case INTEL_PT_MNT:
1823 case INTEL_PT_PAD:
1824 default:
1825 break;
1826 }
1827 }
1828 }
1829
1830 static int intel_pt_walk_to_ip(struct intel_pt_decoder *decoder)
1831 {
1832 int err;
1833
1834 while (1) {
1835 err = intel_pt_get_next_packet(decoder);
1836 if (err)
1837 return err;
1838
1839 switch (decoder->packet.type) {
1840 case INTEL_PT_TIP_PGD:
1841 decoder->continuous_period = false;
1842 case INTEL_PT_TIP_PGE:
1843 case INTEL_PT_TIP:
1844 decoder->pge = decoder->packet.type != INTEL_PT_TIP_PGD;
1845 if (intel_pt_have_ip(decoder))
1846 intel_pt_set_ip(decoder);
1847 if (decoder->ip)
1848 return 0;
1849 break;
1850
1851 case INTEL_PT_FUP:
1852 if (decoder->overflow) {
1853 if (intel_pt_have_ip(decoder))
1854 intel_pt_set_ip(decoder);
1855 if (decoder->ip)
1856 return 0;
1857 }
1858 if (decoder->packet.count)
1859 intel_pt_set_last_ip(decoder);
1860 break;
1861
1862 case INTEL_PT_MTC:
1863 intel_pt_calc_mtc_timestamp(decoder);
1864 break;
1865
1866 case INTEL_PT_TSC:
1867 intel_pt_calc_tsc_timestamp(decoder);
1868 break;
1869
1870 case INTEL_PT_TMA:
1871 intel_pt_calc_tma(decoder);
1872 break;
1873
1874 case INTEL_PT_CYC:
1875 intel_pt_calc_cyc_timestamp(decoder);
1876 break;
1877
1878 case INTEL_PT_CBR:
1879 intel_pt_calc_cbr(decoder);
1880 break;
1881
1882 case INTEL_PT_PIP:
1883 decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1884 break;
1885
1886 case INTEL_PT_MODE_EXEC:
1887 decoder->exec_mode = decoder->packet.payload;
1888 break;
1889
1890 case INTEL_PT_MODE_TSX:
1891 intel_pt_update_in_tx(decoder);
1892 break;
1893
1894 case INTEL_PT_OVF:
1895 return intel_pt_overflow(decoder);
1896
1897 case INTEL_PT_BAD: /* Does not happen */
1898 return intel_pt_bug(decoder);
1899
1900 case INTEL_PT_TRACESTOP:
1901 decoder->pge = false;
1902 decoder->continuous_period = false;
1903 intel_pt_clear_tx_flags(decoder);
1904 decoder->have_tma = false;
1905 break;
1906
1907 case INTEL_PT_PSB:
1908 err = intel_pt_walk_psb(decoder);
1909 if (err)
1910 return err;
1911 if (decoder->ip) {
1912 /* Do not have a sample */
1913 decoder->state.type = 0;
1914 return 0;
1915 }
1916 break;
1917
1918 case INTEL_PT_TNT:
1919 case INTEL_PT_PSBEND:
1920 case INTEL_PT_VMCS:
1921 case INTEL_PT_MNT:
1922 case INTEL_PT_PAD:
1923 default:
1924 break;
1925 }
1926 }
1927 }
1928
1929 static int intel_pt_sync_ip(struct intel_pt_decoder *decoder)
1930 {
1931 int err;
1932
1933 intel_pt_log("Scanning for full IP\n");
1934 err = intel_pt_walk_to_ip(decoder);
1935 if (err)
1936 return err;
1937
1938 decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1939 decoder->overflow = false;
1940
1941 decoder->state.from_ip = 0;
1942 decoder->state.to_ip = decoder->ip;
1943 intel_pt_log_to("Setting IP", decoder->ip);
1944
1945 return 0;
1946 }
1947
1948 static int intel_pt_part_psb(struct intel_pt_decoder *decoder)
1949 {
1950 const unsigned char *end = decoder->buf + decoder->len;
1951 size_t i;
1952
1953 for (i = INTEL_PT_PSB_LEN - 1; i; i--) {
1954 if (i > decoder->len)
1955 continue;
1956 if (!memcmp(end - i, INTEL_PT_PSB_STR, i))
1957 return i;
1958 }
1959 return 0;
1960 }
1961
1962 static int intel_pt_rest_psb(struct intel_pt_decoder *decoder, int part_psb)
1963 {
1964 size_t rest_psb = INTEL_PT_PSB_LEN - part_psb;
1965 const char *psb = INTEL_PT_PSB_STR;
1966
1967 if (rest_psb > decoder->len ||
1968 memcmp(decoder->buf, psb + part_psb, rest_psb))
1969 return 0;
1970
1971 return rest_psb;
1972 }
1973
1974 static int intel_pt_get_split_psb(struct intel_pt_decoder *decoder,
1975 int part_psb)
1976 {
1977 int rest_psb, ret;
1978
1979 decoder->pos += decoder->len;
1980 decoder->len = 0;
1981
1982 ret = intel_pt_get_next_data(decoder);
1983 if (ret)
1984 return ret;
1985
1986 rest_psb = intel_pt_rest_psb(decoder, part_psb);
1987 if (!rest_psb)
1988 return 0;
1989
1990 decoder->pos -= part_psb;
1991 decoder->next_buf = decoder->buf + rest_psb;
1992 decoder->next_len = decoder->len - rest_psb;
1993 memcpy(decoder->temp_buf, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
1994 decoder->buf = decoder->temp_buf;
1995 decoder->len = INTEL_PT_PSB_LEN;
1996
1997 return 0;
1998 }
1999
2000 static int intel_pt_scan_for_psb(struct intel_pt_decoder *decoder)
2001 {
2002 unsigned char *next;
2003 int ret;
2004
2005 intel_pt_log("Scanning for PSB\n");
2006 while (1) {
2007 if (!decoder->len) {
2008 ret = intel_pt_get_next_data(decoder);
2009 if (ret)
2010 return ret;
2011 }
2012
2013 next = memmem(decoder->buf, decoder->len, INTEL_PT_PSB_STR,
2014 INTEL_PT_PSB_LEN);
2015 if (!next) {
2016 int part_psb;
2017
2018 part_psb = intel_pt_part_psb(decoder);
2019 if (part_psb) {
2020 ret = intel_pt_get_split_psb(decoder, part_psb);
2021 if (ret)
2022 return ret;
2023 } else {
2024 decoder->pos += decoder->len;
2025 decoder->len = 0;
2026 }
2027 continue;
2028 }
2029
2030 decoder->pkt_step = next - decoder->buf;
2031 return intel_pt_get_next_packet(decoder);
2032 }
2033 }
2034
2035 static int intel_pt_sync(struct intel_pt_decoder *decoder)
2036 {
2037 int err;
2038
2039 decoder->pge = false;
2040 decoder->continuous_period = false;
2041 decoder->last_ip = 0;
2042 decoder->ip = 0;
2043 intel_pt_clear_stack(&decoder->stack);
2044
2045 err = intel_pt_scan_for_psb(decoder);
2046 if (err)
2047 return err;
2048
2049 decoder->pkt_state = INTEL_PT_STATE_NO_IP;
2050
2051 err = intel_pt_walk_psb(decoder);
2052 if (err)
2053 return err;
2054
2055 if (decoder->ip) {
2056 decoder->state.type = 0; /* Do not have a sample */
2057 decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2058 } else {
2059 return intel_pt_sync_ip(decoder);
2060 }
2061
2062 return 0;
2063 }
2064
2065 static uint64_t intel_pt_est_timestamp(struct intel_pt_decoder *decoder)
2066 {
2067 uint64_t est = decoder->timestamp_insn_cnt << 1;
2068
2069 if (!decoder->cbr || !decoder->max_non_turbo_ratio)
2070 goto out;
2071
2072 est *= decoder->max_non_turbo_ratio;
2073 est /= decoder->cbr;
2074 out:
2075 return decoder->timestamp + est;
2076 }
2077
2078 const struct intel_pt_state *intel_pt_decode(struct intel_pt_decoder *decoder)
2079 {
2080 int err;
2081
2082 do {
2083 decoder->state.type = INTEL_PT_BRANCH;
2084 decoder->state.flags = 0;
2085
2086 switch (decoder->pkt_state) {
2087 case INTEL_PT_STATE_NO_PSB:
2088 err = intel_pt_sync(decoder);
2089 break;
2090 case INTEL_PT_STATE_NO_IP:
2091 decoder->last_ip = 0;
2092 /* Fall through */
2093 case INTEL_PT_STATE_ERR_RESYNC:
2094 err = intel_pt_sync_ip(decoder);
2095 break;
2096 case INTEL_PT_STATE_IN_SYNC:
2097 err = intel_pt_walk_trace(decoder);
2098 break;
2099 case INTEL_PT_STATE_TNT:
2100 err = intel_pt_walk_tnt(decoder);
2101 if (err == -EAGAIN)
2102 err = intel_pt_walk_trace(decoder);
2103 break;
2104 case INTEL_PT_STATE_TIP:
2105 case INTEL_PT_STATE_TIP_PGD:
2106 err = intel_pt_walk_tip(decoder);
2107 break;
2108 case INTEL_PT_STATE_FUP:
2109 decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2110 err = intel_pt_walk_fup(decoder);
2111 if (err == -EAGAIN)
2112 err = intel_pt_walk_fup_tip(decoder);
2113 else if (!err)
2114 decoder->pkt_state = INTEL_PT_STATE_FUP;
2115 break;
2116 case INTEL_PT_STATE_FUP_NO_TIP:
2117 decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2118 err = intel_pt_walk_fup(decoder);
2119 if (err == -EAGAIN)
2120 err = intel_pt_walk_trace(decoder);
2121 break;
2122 default:
2123 err = intel_pt_bug(decoder);
2124 break;
2125 }
2126 } while (err == -ENOLINK);
2127
2128 decoder->state.err = err ? intel_pt_ext_err(err) : 0;
2129 decoder->state.timestamp = decoder->timestamp;
2130 decoder->state.est_timestamp = intel_pt_est_timestamp(decoder);
2131 decoder->state.cr3 = decoder->cr3;
2132 decoder->state.tot_insn_cnt = decoder->tot_insn_cnt;
2133
2134 if (err)
2135 decoder->state.from_ip = decoder->ip;
2136
2137 return &decoder->state;
2138 }
2139
2140 static bool intel_pt_at_psb(unsigned char *buf, size_t len)
2141 {
2142 if (len < INTEL_PT_PSB_LEN)
2143 return false;
2144 return memmem(buf, INTEL_PT_PSB_LEN, INTEL_PT_PSB_STR,
2145 INTEL_PT_PSB_LEN);
2146 }
2147
2148 /**
2149 * intel_pt_next_psb - move buffer pointer to the start of the next PSB packet.
2150 * @buf: pointer to buffer pointer
2151 * @len: size of buffer
2152 *
2153 * Updates the buffer pointer to point to the start of the next PSB packet if
2154 * there is one, otherwise the buffer pointer is unchanged. If @buf is updated,
2155 * @len is adjusted accordingly.
2156 *
2157 * Return: %true if a PSB packet is found, %false otherwise.
2158 */
2159 static bool intel_pt_next_psb(unsigned char **buf, size_t *len)
2160 {
2161 unsigned char *next;
2162
2163 next = memmem(*buf, *len, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2164 if (next) {
2165 *len -= next - *buf;
2166 *buf = next;
2167 return true;
2168 }
2169 return false;
2170 }
2171
2172 /**
2173 * intel_pt_step_psb - move buffer pointer to the start of the following PSB
2174 * packet.
2175 * @buf: pointer to buffer pointer
2176 * @len: size of buffer
2177 *
2178 * Updates the buffer pointer to point to the start of the following PSB packet
2179 * (skipping the PSB at @buf itself) if there is one, otherwise the buffer
2180 * pointer is unchanged. If @buf is updated, @len is adjusted accordingly.
2181 *
2182 * Return: %true if a PSB packet is found, %false otherwise.
2183 */
2184 static bool intel_pt_step_psb(unsigned char **buf, size_t *len)
2185 {
2186 unsigned char *next;
2187
2188 if (!*len)
2189 return false;
2190
2191 next = memmem(*buf + 1, *len - 1, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2192 if (next) {
2193 *len -= next - *buf;
2194 *buf = next;
2195 return true;
2196 }
2197 return false;
2198 }
2199
2200 /**
2201 * intel_pt_last_psb - find the last PSB packet in a buffer.
2202 * @buf: buffer
2203 * @len: size of buffer
2204 *
2205 * This function finds the last PSB in a buffer.
2206 *
2207 * Return: A pointer to the last PSB in @buf if found, %NULL otherwise.
2208 */
2209 static unsigned char *intel_pt_last_psb(unsigned char *buf, size_t len)
2210 {
2211 const char *n = INTEL_PT_PSB_STR;
2212 unsigned char *p;
2213 size_t k;
2214
2215 if (len < INTEL_PT_PSB_LEN)
2216 return NULL;
2217
2218 k = len - INTEL_PT_PSB_LEN + 1;
2219 while (1) {
2220 p = memrchr(buf, n[0], k);
2221 if (!p)
2222 return NULL;
2223 if (!memcmp(p + 1, n + 1, INTEL_PT_PSB_LEN - 1))
2224 return p;
2225 k = p - buf;
2226 if (!k)
2227 return NULL;
2228 }
2229 }
2230
2231 /**
2232 * intel_pt_next_tsc - find and return next TSC.
2233 * @buf: buffer
2234 * @len: size of buffer
2235 * @tsc: TSC value returned
2236 *
2237 * Find a TSC packet in @buf and return the TSC value. This function assumes
2238 * that @buf starts at a PSB and that PSB+ will contain TSC and so stops if a
2239 * PSBEND packet is found.
2240 *
2241 * Return: %true if TSC is found, false otherwise.
2242 */
2243 static bool intel_pt_next_tsc(unsigned char *buf, size_t len, uint64_t *tsc)
2244 {
2245 struct intel_pt_pkt packet;
2246 int ret;
2247
2248 while (len) {
2249 ret = intel_pt_get_packet(buf, len, &packet);
2250 if (ret <= 0)
2251 return false;
2252 if (packet.type == INTEL_PT_TSC) {
2253 *tsc = packet.payload;
2254 return true;
2255 }
2256 if (packet.type == INTEL_PT_PSBEND)
2257 return false;
2258 buf += ret;
2259 len -= ret;
2260 }
2261 return false;
2262 }
2263
2264 /**
2265 * intel_pt_tsc_cmp - compare 7-byte TSCs.
2266 * @tsc1: first TSC to compare
2267 * @tsc2: second TSC to compare
2268 *
2269 * This function compares 7-byte TSC values allowing for the possibility that
2270 * TSC wrapped around. Generally it is not possible to know if TSC has wrapped
2271 * around so for that purpose this function assumes the absolute difference is
2272 * less than half the maximum difference.
2273 *
2274 * Return: %-1 if @tsc1 is before @tsc2, %0 if @tsc1 == @tsc2, %1 if @tsc1 is
2275 * after @tsc2.
2276 */
2277 static int intel_pt_tsc_cmp(uint64_t tsc1, uint64_t tsc2)
2278 {
2279 const uint64_t halfway = (1ULL << 55);
2280
2281 if (tsc1 == tsc2)
2282 return 0;
2283
2284 if (tsc1 < tsc2) {
2285 if (tsc2 - tsc1 < halfway)
2286 return -1;
2287 else
2288 return 1;
2289 } else {
2290 if (tsc1 - tsc2 < halfway)
2291 return 1;
2292 else
2293 return -1;
2294 }
2295 }
2296
2297 /**
2298 * intel_pt_find_overlap_tsc - determine start of non-overlapped trace data
2299 * using TSC.
2300 * @buf_a: first buffer
2301 * @len_a: size of first buffer
2302 * @buf_b: second buffer
2303 * @len_b: size of second buffer
2304 *
2305 * If the trace contains TSC we can look at the last TSC of @buf_a and the
2306 * first TSC of @buf_b in order to determine if the buffers overlap, and then
2307 * walk forward in @buf_b until a later TSC is found. A precondition is that
2308 * @buf_a and @buf_b are positioned at a PSB.
2309 *
2310 * Return: A pointer into @buf_b from where non-overlapped data starts, or
2311 * @buf_b + @len_b if there is no non-overlapped data.
2312 */
2313 static unsigned char *intel_pt_find_overlap_tsc(unsigned char *buf_a,
2314 size_t len_a,
2315 unsigned char *buf_b,
2316 size_t len_b)
2317 {
2318 uint64_t tsc_a, tsc_b;
2319 unsigned char *p;
2320 size_t len;
2321
2322 p = intel_pt_last_psb(buf_a, len_a);
2323 if (!p)
2324 return buf_b; /* No PSB in buf_a => no overlap */
2325
2326 len = len_a - (p - buf_a);
2327 if (!intel_pt_next_tsc(p, len, &tsc_a)) {
2328 /* The last PSB+ in buf_a is incomplete, so go back one more */
2329 len_a -= len;
2330 p = intel_pt_last_psb(buf_a, len_a);
2331 if (!p)
2332 return buf_b; /* No full PSB+ => assume no overlap */
2333 len = len_a - (p - buf_a);
2334 if (!intel_pt_next_tsc(p, len, &tsc_a))
2335 return buf_b; /* No TSC in buf_a => assume no overlap */
2336 }
2337
2338 while (1) {
2339 /* Ignore PSB+ with no TSC */
2340 if (intel_pt_next_tsc(buf_b, len_b, &tsc_b) &&
2341 intel_pt_tsc_cmp(tsc_a, tsc_b) < 0)
2342 return buf_b; /* tsc_a < tsc_b => no overlap */
2343
2344 if (!intel_pt_step_psb(&buf_b, &len_b))
2345 return buf_b + len_b; /* No PSB in buf_b => no data */
2346 }
2347 }
2348
2349 /**
2350 * intel_pt_find_overlap - determine start of non-overlapped trace data.
2351 * @buf_a: first buffer
2352 * @len_a: size of first buffer
2353 * @buf_b: second buffer
2354 * @len_b: size of second buffer
2355 * @have_tsc: can use TSC packets to detect overlap
2356 *
2357 * When trace samples or snapshots are recorded there is the possibility that
2358 * the data overlaps. Note that, for the purposes of decoding, data is only
2359 * useful if it begins with a PSB packet.
2360 *
2361 * Return: A pointer into @buf_b from where non-overlapped data starts, or
2362 * @buf_b + @len_b if there is no non-overlapped data.
2363 */
2364 unsigned char *intel_pt_find_overlap(unsigned char *buf_a, size_t len_a,
2365 unsigned char *buf_b, size_t len_b,
2366 bool have_tsc)
2367 {
2368 unsigned char *found;
2369
2370 /* Buffer 'b' must start at PSB so throw away everything before that */
2371 if (!intel_pt_next_psb(&buf_b, &len_b))
2372 return buf_b + len_b; /* No PSB */
2373
2374 if (!intel_pt_next_psb(&buf_a, &len_a))
2375 return buf_b; /* No overlap */
2376
2377 if (have_tsc) {
2378 found = intel_pt_find_overlap_tsc(buf_a, len_a, buf_b, len_b);
2379 if (found)
2380 return found;
2381 }
2382
2383 /*
2384 * Buffer 'b' cannot end within buffer 'a' so, for comparison purposes,
2385 * we can ignore the first part of buffer 'a'.
2386 */
2387 while (len_b < len_a) {
2388 if (!intel_pt_step_psb(&buf_a, &len_a))
2389 return buf_b; /* No overlap */
2390 }
2391
2392 /* Now len_b >= len_a */
2393 if (len_b > len_a) {
2394 /* The leftover buffer 'b' must start at a PSB */
2395 while (!intel_pt_at_psb(buf_b + len_a, len_b - len_a)) {
2396 if (!intel_pt_step_psb(&buf_a, &len_a))
2397 return buf_b; /* No overlap */
2398 }
2399 }
2400
2401 while (1) {
2402 /* Potential overlap so check the bytes */
2403 found = memmem(buf_a, len_a, buf_b, len_a);
2404 if (found)
2405 return buf_b + len_a;
2406
2407 /* Try again at next PSB in buffer 'a' */
2408 if (!intel_pt_step_psb(&buf_a, &len_a))
2409 return buf_b; /* No overlap */
2410
2411 /* The leftover buffer 'b' must start at a PSB */
2412 while (!intel_pt_at_psb(buf_b + len_a, len_b - len_a)) {
2413 if (!intel_pt_step_psb(&buf_a, &len_a))
2414 return buf_b; /* No overlap */
2415 }
2416 }
2417 }
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