~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c

Version: ~ [ linux-5.6-rc7 ] ~ [ linux-5.5.11 ] ~ [ linux-5.4.27 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.112 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.174 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.217 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.217 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.140 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.82 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

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

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp