linux/tools/perf/util/intel-pt-decoder/intel-pt-decoder.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * intel_pt_decoder.c: Intel Processor Trace support
   4 * Copyright (c) 2013-2014, Intel Corporation.
   5 */
   6
   7#ifndef _GNU_SOURCE
   8#define _GNU_SOURCE
   9#endif
  10#include <stdlib.h>
  11#include <stdbool.h>
  12#include <string.h>
  13#include <errno.h>
  14#include <stdint.h>
  15#include <inttypes.h>
  16#include <linux/compiler.h>
  17#include <linux/string.h>
  18#include <linux/zalloc.h>
  19
  20#include "../auxtrace.h"
  21
  22#include "intel-pt-insn-decoder.h"
  23#include "intel-pt-pkt-decoder.h"
  24#include "intel-pt-decoder.h"
  25#include "intel-pt-log.h"
  26
  27#define BITULL(x) (1ULL << (x))
  28
  29/* IA32_RTIT_CTL MSR bits */
  30#define INTEL_PT_CYC_ENABLE             BITULL(1)
  31#define INTEL_PT_CYC_THRESHOLD          (BITULL(22) | BITULL(21) | BITULL(20) | BITULL(19))
  32#define INTEL_PT_CYC_THRESHOLD_SHIFT    19
  33
  34#define INTEL_PT_BLK_SIZE 1024
  35
  36#define BIT63 (((uint64_t)1 << 63))
  37
  38#define SEVEN_BYTES 0xffffffffffffffULL
  39
  40#define NO_VMCS 0xffffffffffULL
  41
  42#define INTEL_PT_RETURN 1
  43
  44/*
  45 * Default maximum number of loops with no packets consumed i.e. stuck in a
  46 * loop.
  47 */
  48#define INTEL_PT_MAX_LOOPS 100000
  49
  50struct intel_pt_blk {
  51        struct intel_pt_blk *prev;
  52        uint64_t ip[INTEL_PT_BLK_SIZE];
  53};
  54
  55struct intel_pt_stack {
  56        struct intel_pt_blk *blk;
  57        struct intel_pt_blk *spare;
  58        int pos;
  59};
  60
  61enum intel_pt_p_once {
  62        INTEL_PT_PRT_ONCE_UNK_VMCS,
  63        INTEL_PT_PRT_ONCE_ERANGE,
  64};
  65
  66enum intel_pt_pkt_state {
  67        INTEL_PT_STATE_NO_PSB,
  68        INTEL_PT_STATE_NO_IP,
  69        INTEL_PT_STATE_ERR_RESYNC,
  70        INTEL_PT_STATE_IN_SYNC,
  71        INTEL_PT_STATE_TNT_CONT,
  72        INTEL_PT_STATE_TNT,
  73        INTEL_PT_STATE_TIP,
  74        INTEL_PT_STATE_TIP_PGD,
  75        INTEL_PT_STATE_FUP,
  76        INTEL_PT_STATE_FUP_NO_TIP,
  77        INTEL_PT_STATE_FUP_IN_PSB,
  78        INTEL_PT_STATE_RESAMPLE,
  79        INTEL_PT_STATE_VM_TIME_CORRELATION,
  80};
  81
  82static inline bool intel_pt_sample_time(enum intel_pt_pkt_state pkt_state)
  83{
  84        switch (pkt_state) {
  85        case INTEL_PT_STATE_NO_PSB:
  86        case INTEL_PT_STATE_NO_IP:
  87        case INTEL_PT_STATE_ERR_RESYNC:
  88        case INTEL_PT_STATE_IN_SYNC:
  89        case INTEL_PT_STATE_TNT_CONT:
  90        case INTEL_PT_STATE_RESAMPLE:
  91        case INTEL_PT_STATE_VM_TIME_CORRELATION:
  92                return true;
  93        case INTEL_PT_STATE_TNT:
  94        case INTEL_PT_STATE_TIP:
  95        case INTEL_PT_STATE_TIP_PGD:
  96        case INTEL_PT_STATE_FUP:
  97        case INTEL_PT_STATE_FUP_NO_TIP:
  98        case INTEL_PT_STATE_FUP_IN_PSB:
  99                return false;
 100        default:
 101                return true;
 102        };
 103}
 104
 105#ifdef INTEL_PT_STRICT
 106#define INTEL_PT_STATE_ERR1     INTEL_PT_STATE_NO_PSB
 107#define INTEL_PT_STATE_ERR2     INTEL_PT_STATE_NO_PSB
 108#define INTEL_PT_STATE_ERR3     INTEL_PT_STATE_NO_PSB
 109#define INTEL_PT_STATE_ERR4     INTEL_PT_STATE_NO_PSB
 110#else
 111#define INTEL_PT_STATE_ERR1     (decoder->pkt_state)
 112#define INTEL_PT_STATE_ERR2     INTEL_PT_STATE_NO_IP
 113#define INTEL_PT_STATE_ERR3     INTEL_PT_STATE_ERR_RESYNC
 114#define INTEL_PT_STATE_ERR4     INTEL_PT_STATE_IN_SYNC
 115#endif
 116
 117struct intel_pt_decoder {
 118        int (*get_trace)(struct intel_pt_buffer *buffer, void *data);
 119        int (*walk_insn)(struct intel_pt_insn *intel_pt_insn,
 120                         uint64_t *insn_cnt_ptr, uint64_t *ip, uint64_t to_ip,
 121                         uint64_t max_insn_cnt, void *data);
 122        bool (*pgd_ip)(uint64_t ip, void *data);
 123        int (*lookahead)(void *data, intel_pt_lookahead_cb_t cb, void *cb_data);
 124        struct intel_pt_vmcs_info *(*findnew_vmcs_info)(void *data, uint64_t vmcs);
 125        void *data;
 126        struct intel_pt_state state;
 127        const unsigned char *buf;
 128        size_t len;
 129        bool return_compression;
 130        bool branch_enable;
 131        bool mtc_insn;
 132        bool pge;
 133        bool have_tma;
 134        bool have_cyc;
 135        bool fixup_last_mtc;
 136        bool have_last_ip;
 137        bool in_psb;
 138        bool hop;
 139        bool leap;
 140        bool vm_time_correlation;
 141        bool vm_tm_corr_dry_run;
 142        bool vm_tm_corr_reliable;
 143        bool vm_tm_corr_same_buf;
 144        bool vm_tm_corr_continuous;
 145        bool nr;
 146        bool next_nr;
 147        enum intel_pt_param_flags flags;
 148        uint64_t pos;
 149        uint64_t last_ip;
 150        uint64_t ip;
 151        uint64_t pip_payload;
 152        uint64_t timestamp;
 153        uint64_t tsc_timestamp;
 154        uint64_t ref_timestamp;
 155        uint64_t buf_timestamp;
 156        uint64_t sample_timestamp;
 157        uint64_t ret_addr;
 158        uint64_t ctc_timestamp;
 159        uint64_t ctc_delta;
 160        uint64_t cycle_cnt;
 161        uint64_t cyc_ref_timestamp;
 162        uint64_t first_timestamp;
 163        uint64_t last_reliable_timestamp;
 164        uint64_t vmcs;
 165        uint64_t print_once;
 166        uint64_t last_ctc;
 167        uint32_t last_mtc;
 168        uint32_t tsc_ctc_ratio_n;
 169        uint32_t tsc_ctc_ratio_d;
 170        uint32_t tsc_ctc_mult;
 171        uint32_t tsc_slip;
 172        uint32_t ctc_rem_mask;
 173        int mtc_shift;
 174        struct intel_pt_stack stack;
 175        enum intel_pt_pkt_state pkt_state;
 176        enum intel_pt_pkt_ctx pkt_ctx;
 177        enum intel_pt_pkt_ctx prev_pkt_ctx;
 178        enum intel_pt_blk_type blk_type;
 179        int blk_type_pos;
 180        struct intel_pt_pkt packet;
 181        struct intel_pt_pkt tnt;
 182        int pkt_step;
 183        int pkt_len;
 184        int last_packet_type;
 185        unsigned int cbr;
 186        unsigned int cbr_seen;
 187        unsigned int max_non_turbo_ratio;
 188        double max_non_turbo_ratio_fp;
 189        double cbr_cyc_to_tsc;
 190        double calc_cyc_to_tsc;
 191        bool have_calc_cyc_to_tsc;
 192        int exec_mode;
 193        unsigned int insn_bytes;
 194        uint64_t period;
 195        enum intel_pt_period_type period_type;
 196        uint64_t tot_insn_cnt;
 197        uint64_t period_insn_cnt;
 198        uint64_t period_mask;
 199        uint64_t period_ticks;
 200        uint64_t last_masked_timestamp;
 201        uint64_t tot_cyc_cnt;
 202        uint64_t sample_tot_cyc_cnt;
 203        uint64_t base_cyc_cnt;
 204        uint64_t cyc_cnt_timestamp;
 205        uint64_t ctl;
 206        uint64_t cyc_threshold;
 207        double tsc_to_cyc;
 208        bool continuous_period;
 209        bool overflow;
 210        bool set_fup_tx_flags;
 211        bool set_fup_ptw;
 212        bool set_fup_mwait;
 213        bool set_fup_pwre;
 214        bool set_fup_exstop;
 215        bool set_fup_bep;
 216        bool sample_cyc;
 217        unsigned int fup_tx_flags;
 218        unsigned int tx_flags;
 219        uint64_t fup_ptw_payload;
 220        uint64_t fup_mwait_payload;
 221        uint64_t fup_pwre_payload;
 222        uint64_t cbr_payload;
 223        uint64_t timestamp_insn_cnt;
 224        uint64_t sample_insn_cnt;
 225        uint64_t stuck_ip;
 226        int max_loops;
 227        int no_progress;
 228        int stuck_ip_prd;
 229        int stuck_ip_cnt;
 230        uint64_t psb_ip;
 231        const unsigned char *next_buf;
 232        size_t next_len;
 233        unsigned char temp_buf[INTEL_PT_PKT_MAX_SZ];
 234};
 235
 236static uint64_t intel_pt_lower_power_of_2(uint64_t x)
 237{
 238        int i;
 239
 240        for (i = 0; x != 1; i++)
 241                x >>= 1;
 242
 243        return x << i;
 244}
 245
 246__printf(1, 2)
 247static void p_log(const char *fmt, ...)
 248{
 249        char buf[512];
 250        va_list args;
 251
 252        va_start(args, fmt);
 253        vsnprintf(buf, sizeof(buf), fmt, args);
 254        va_end(args);
 255
 256        fprintf(stderr, "%s\n", buf);
 257        intel_pt_log("%s\n", buf);
 258}
 259
 260static bool intel_pt_print_once(struct intel_pt_decoder *decoder,
 261                                enum intel_pt_p_once id)
 262{
 263        uint64_t bit = 1ULL << id;
 264
 265        if (decoder->print_once & bit)
 266                return false;
 267        decoder->print_once |= bit;
 268        return true;
 269}
 270
 271static uint64_t intel_pt_cyc_threshold(uint64_t ctl)
 272{
 273        if (!(ctl & INTEL_PT_CYC_ENABLE))
 274                return 0;
 275
 276        return (ctl & INTEL_PT_CYC_THRESHOLD) >> INTEL_PT_CYC_THRESHOLD_SHIFT;
 277}
 278
 279static void intel_pt_setup_period(struct intel_pt_decoder *decoder)
 280{
 281        if (decoder->period_type == INTEL_PT_PERIOD_TICKS) {
 282                uint64_t period;
 283
 284                period = intel_pt_lower_power_of_2(decoder->period);
 285                decoder->period_mask  = ~(period - 1);
 286                decoder->period_ticks = period;
 287        }
 288}
 289
 290static uint64_t multdiv(uint64_t t, uint32_t n, uint32_t d)
 291{
 292        if (!d)
 293                return 0;
 294        return (t / d) * n + ((t % d) * n) / d;
 295}
 296
 297struct intel_pt_decoder *intel_pt_decoder_new(struct intel_pt_params *params)
 298{
 299        struct intel_pt_decoder *decoder;
 300
 301        if (!params->get_trace || !params->walk_insn)
 302                return NULL;
 303
 304        decoder = zalloc(sizeof(struct intel_pt_decoder));
 305        if (!decoder)
 306                return NULL;
 307
 308        decoder->get_trace          = params->get_trace;
 309        decoder->walk_insn          = params->walk_insn;
 310        decoder->pgd_ip             = params->pgd_ip;
 311        decoder->lookahead          = params->lookahead;
 312        decoder->findnew_vmcs_info  = params->findnew_vmcs_info;
 313        decoder->data               = params->data;
 314        decoder->return_compression = params->return_compression;
 315        decoder->branch_enable      = params->branch_enable;
 316        decoder->hop                = params->quick >= 1;
 317        decoder->leap               = params->quick >= 2;
 318        decoder->vm_time_correlation = params->vm_time_correlation;
 319        decoder->vm_tm_corr_dry_run = params->vm_tm_corr_dry_run;
 320        decoder->first_timestamp    = params->first_timestamp;
 321        decoder->last_reliable_timestamp = params->first_timestamp;
 322        decoder->max_loops          = params->max_loops ? params->max_loops : INTEL_PT_MAX_LOOPS;
 323
 324        decoder->flags              = params->flags;
 325
 326        decoder->ctl                = params->ctl;
 327        decoder->period             = params->period;
 328        decoder->period_type        = params->period_type;
 329
 330        decoder->max_non_turbo_ratio    = params->max_non_turbo_ratio;
 331        decoder->max_non_turbo_ratio_fp = params->max_non_turbo_ratio;
 332
 333        decoder->cyc_threshold = intel_pt_cyc_threshold(decoder->ctl);
 334
 335        intel_pt_setup_period(decoder);
 336
 337        decoder->mtc_shift = params->mtc_period;
 338        decoder->ctc_rem_mask = (1 << decoder->mtc_shift) - 1;
 339
 340        decoder->tsc_ctc_ratio_n = params->tsc_ctc_ratio_n;
 341        decoder->tsc_ctc_ratio_d = params->tsc_ctc_ratio_d;
 342
 343        if (!decoder->tsc_ctc_ratio_n)
 344                decoder->tsc_ctc_ratio_d = 0;
 345
 346        if (decoder->tsc_ctc_ratio_d) {
 347                if (!(decoder->tsc_ctc_ratio_n % decoder->tsc_ctc_ratio_d))
 348                        decoder->tsc_ctc_mult = decoder->tsc_ctc_ratio_n /
 349                                                decoder->tsc_ctc_ratio_d;
 350        }
 351
 352        /*
 353         * A TSC packet can slip past MTC packets so that the timestamp appears
 354         * to go backwards. One estimate is that can be up to about 40 CPU
 355         * cycles, which is certainly less than 0x1000 TSC ticks, but accept
 356         * slippage an order of magnitude more to be on the safe side.
 357         */
 358        decoder->tsc_slip = 0x10000;
 359
 360        intel_pt_log("timestamp: mtc_shift %u\n", decoder->mtc_shift);
 361        intel_pt_log("timestamp: tsc_ctc_ratio_n %u\n", decoder->tsc_ctc_ratio_n);
 362        intel_pt_log("timestamp: tsc_ctc_ratio_d %u\n", decoder->tsc_ctc_ratio_d);
 363        intel_pt_log("timestamp: tsc_ctc_mult %u\n", decoder->tsc_ctc_mult);
 364        intel_pt_log("timestamp: tsc_slip %#x\n", decoder->tsc_slip);
 365
 366        if (decoder->hop)
 367                intel_pt_log("Hop mode: decoding FUP and TIPs, but not TNT\n");
 368
 369        return decoder;
 370}
 371
 372void intel_pt_set_first_timestamp(struct intel_pt_decoder *decoder,
 373                                  uint64_t first_timestamp)
 374{
 375        decoder->first_timestamp = first_timestamp;
 376}
 377
 378static void intel_pt_pop_blk(struct intel_pt_stack *stack)
 379{
 380        struct intel_pt_blk *blk = stack->blk;
 381
 382        stack->blk = blk->prev;
 383        if (!stack->spare)
 384                stack->spare = blk;
 385        else
 386                free(blk);
 387}
 388
 389static uint64_t intel_pt_pop(struct intel_pt_stack *stack)
 390{
 391        if (!stack->pos) {
 392                if (!stack->blk)
 393                        return 0;
 394                intel_pt_pop_blk(stack);
 395                if (!stack->blk)
 396                        return 0;
 397                stack->pos = INTEL_PT_BLK_SIZE;
 398        }
 399        return stack->blk->ip[--stack->pos];
 400}
 401
 402static int intel_pt_alloc_blk(struct intel_pt_stack *stack)
 403{
 404        struct intel_pt_blk *blk;
 405
 406        if (stack->spare) {
 407                blk = stack->spare;
 408                stack->spare = NULL;
 409        } else {
 410                blk = malloc(sizeof(struct intel_pt_blk));
 411                if (!blk)
 412                        return -ENOMEM;
 413        }
 414
 415        blk->prev = stack->blk;
 416        stack->blk = blk;
 417        stack->pos = 0;
 418        return 0;
 419}
 420
 421static int intel_pt_push(struct intel_pt_stack *stack, uint64_t ip)
 422{
 423        int err;
 424
 425        if (!stack->blk || stack->pos == INTEL_PT_BLK_SIZE) {
 426                err = intel_pt_alloc_blk(stack);
 427                if (err)
 428                        return err;
 429        }
 430
 431        stack->blk->ip[stack->pos++] = ip;
 432        return 0;
 433}
 434
 435static void intel_pt_clear_stack(struct intel_pt_stack *stack)
 436{
 437        while (stack->blk)
 438                intel_pt_pop_blk(stack);
 439        stack->pos = 0;
 440}
 441
 442static void intel_pt_free_stack(struct intel_pt_stack *stack)
 443{
 444        intel_pt_clear_stack(stack);
 445        zfree(&stack->blk);
 446        zfree(&stack->spare);
 447}
 448
 449void intel_pt_decoder_free(struct intel_pt_decoder *decoder)
 450{
 451        intel_pt_free_stack(&decoder->stack);
 452        free(decoder);
 453}
 454
 455static int intel_pt_ext_err(int code)
 456{
 457        switch (code) {
 458        case -ENOMEM:
 459                return INTEL_PT_ERR_NOMEM;
 460        case -ENOSYS:
 461                return INTEL_PT_ERR_INTERN;
 462        case -EBADMSG:
 463                return INTEL_PT_ERR_BADPKT;
 464        case -ENODATA:
 465                return INTEL_PT_ERR_NODATA;
 466        case -EILSEQ:
 467                return INTEL_PT_ERR_NOINSN;
 468        case -ENOENT:
 469                return INTEL_PT_ERR_MISMAT;
 470        case -EOVERFLOW:
 471                return INTEL_PT_ERR_OVR;
 472        case -ENOSPC:
 473                return INTEL_PT_ERR_LOST;
 474        case -ELOOP:
 475                return INTEL_PT_ERR_NELOOP;
 476        default:
 477                return INTEL_PT_ERR_UNK;
 478        }
 479}
 480
 481static const char *intel_pt_err_msgs[] = {
 482        [INTEL_PT_ERR_NOMEM]  = "Memory allocation failed",
 483        [INTEL_PT_ERR_INTERN] = "Internal error",
 484        [INTEL_PT_ERR_BADPKT] = "Bad packet",
 485        [INTEL_PT_ERR_NODATA] = "No more data",
 486        [INTEL_PT_ERR_NOINSN] = "Failed to get instruction",
 487        [INTEL_PT_ERR_MISMAT] = "Trace doesn't match instruction",
 488        [INTEL_PT_ERR_OVR]    = "Overflow packet",
 489        [INTEL_PT_ERR_LOST]   = "Lost trace data",
 490        [INTEL_PT_ERR_UNK]    = "Unknown error!",
 491        [INTEL_PT_ERR_NELOOP] = "Never-ending loop (refer perf config intel-pt.max-loops)",
 492};
 493
 494int intel_pt__strerror(int code, char *buf, size_t buflen)
 495{
 496        if (code < 1 || code >= INTEL_PT_ERR_MAX)
 497                code = INTEL_PT_ERR_UNK;
 498        strlcpy(buf, intel_pt_err_msgs[code], buflen);
 499        return 0;
 500}
 501
 502static uint64_t intel_pt_calc_ip(const struct intel_pt_pkt *packet,
 503                                 uint64_t last_ip)
 504{
 505        uint64_t ip;
 506
 507        switch (packet->count) {
 508        case 1:
 509                ip = (last_ip & (uint64_t)0xffffffffffff0000ULL) |
 510                     packet->payload;
 511                break;
 512        case 2:
 513                ip = (last_ip & (uint64_t)0xffffffff00000000ULL) |
 514                     packet->payload;
 515                break;
 516        case 3:
 517                ip = packet->payload;
 518                /* Sign-extend 6-byte ip */
 519                if (ip & (uint64_t)0x800000000000ULL)
 520                        ip |= (uint64_t)0xffff000000000000ULL;
 521                break;
 522        case 4:
 523                ip = (last_ip & (uint64_t)0xffff000000000000ULL) |
 524                     packet->payload;
 525                break;
 526        case 6:
 527                ip = packet->payload;
 528                break;
 529        default:
 530                return 0;
 531        }
 532
 533        return ip;
 534}
 535
 536static inline void intel_pt_set_last_ip(struct intel_pt_decoder *decoder)
 537{
 538        decoder->last_ip = intel_pt_calc_ip(&decoder->packet, decoder->last_ip);
 539        decoder->have_last_ip = true;
 540}
 541
 542static inline void intel_pt_set_ip(struct intel_pt_decoder *decoder)
 543{
 544        intel_pt_set_last_ip(decoder);
 545        decoder->ip = decoder->last_ip;
 546}
 547
 548static void intel_pt_decoder_log_packet(struct intel_pt_decoder *decoder)
 549{
 550        intel_pt_log_packet(&decoder->packet, decoder->pkt_len, decoder->pos,
 551                            decoder->buf);
 552}
 553
 554static int intel_pt_bug(struct intel_pt_decoder *decoder)
 555{
 556        intel_pt_log("ERROR: Internal error\n");
 557        decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
 558        return -ENOSYS;
 559}
 560
 561static inline void intel_pt_clear_tx_flags(struct intel_pt_decoder *decoder)
 562{
 563        decoder->tx_flags = 0;
 564}
 565
 566static inline void intel_pt_update_in_tx(struct intel_pt_decoder *decoder)
 567{
 568        decoder->tx_flags = decoder->packet.payload & INTEL_PT_IN_TX;
 569}
 570
 571static inline void intel_pt_update_pip(struct intel_pt_decoder *decoder)
 572{
 573        decoder->pip_payload = decoder->packet.payload;
 574}
 575
 576static inline void intel_pt_update_nr(struct intel_pt_decoder *decoder)
 577{
 578        decoder->next_nr = decoder->pip_payload & 1;
 579}
 580
 581static inline void intel_pt_set_nr(struct intel_pt_decoder *decoder)
 582{
 583        decoder->nr = decoder->pip_payload & 1;
 584        decoder->next_nr = decoder->nr;
 585}
 586
 587static inline void intel_pt_set_pip(struct intel_pt_decoder *decoder)
 588{
 589        intel_pt_update_pip(decoder);
 590        intel_pt_set_nr(decoder);
 591}
 592
 593static int intel_pt_bad_packet(struct intel_pt_decoder *decoder)
 594{
 595        intel_pt_clear_tx_flags(decoder);
 596        decoder->have_tma = false;
 597        decoder->pkt_len = 1;
 598        decoder->pkt_step = 1;
 599        intel_pt_decoder_log_packet(decoder);
 600        if (decoder->pkt_state != INTEL_PT_STATE_NO_PSB) {
 601                intel_pt_log("ERROR: Bad packet\n");
 602                decoder->pkt_state = INTEL_PT_STATE_ERR1;
 603        }
 604        return -EBADMSG;
 605}
 606
 607static inline void intel_pt_update_sample_time(struct intel_pt_decoder *decoder)
 608{
 609        decoder->sample_timestamp = decoder->timestamp;
 610        decoder->sample_insn_cnt = decoder->timestamp_insn_cnt;
 611}
 612
 613static void intel_pt_reposition(struct intel_pt_decoder *decoder)
 614{
 615        decoder->ip = 0;
 616        decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
 617        decoder->timestamp = 0;
 618        decoder->have_tma = false;
 619}
 620
 621static int intel_pt_get_data(struct intel_pt_decoder *decoder, bool reposition)
 622{
 623        struct intel_pt_buffer buffer = { .buf = 0, };
 624        int ret;
 625
 626        decoder->pkt_step = 0;
 627
 628        intel_pt_log("Getting more data\n");
 629        ret = decoder->get_trace(&buffer, decoder->data);
 630        if (ret)
 631                return ret;
 632        decoder->buf = buffer.buf;
 633        decoder->len = buffer.len;
 634        if (!decoder->len) {
 635                intel_pt_log("No more data\n");
 636                return -ENODATA;
 637        }
 638        decoder->buf_timestamp = buffer.ref_timestamp;
 639        if (!buffer.consecutive || reposition) {
 640                intel_pt_reposition(decoder);
 641                decoder->ref_timestamp = buffer.ref_timestamp;
 642                decoder->state.trace_nr = buffer.trace_nr;
 643                decoder->vm_tm_corr_same_buf = false;
 644                intel_pt_log("Reference timestamp 0x%" PRIx64 "\n",
 645                             decoder->ref_timestamp);
 646                return -ENOLINK;
 647        }
 648
 649        return 0;
 650}
 651
 652static int intel_pt_get_next_data(struct intel_pt_decoder *decoder,
 653                                  bool reposition)
 654{
 655        if (!decoder->next_buf)
 656                return intel_pt_get_data(decoder, reposition);
 657
 658        decoder->buf = decoder->next_buf;
 659        decoder->len = decoder->next_len;
 660        decoder->next_buf = 0;
 661        decoder->next_len = 0;
 662        return 0;
 663}
 664
 665static int intel_pt_get_split_packet(struct intel_pt_decoder *decoder)
 666{
 667        unsigned char *buf = decoder->temp_buf;
 668        size_t old_len, len, n;
 669        int ret;
 670
 671        old_len = decoder->len;
 672        len = decoder->len;
 673        memcpy(buf, decoder->buf, len);
 674
 675        ret = intel_pt_get_data(decoder, false);
 676        if (ret) {
 677                decoder->pos += old_len;
 678                return ret < 0 ? ret : -EINVAL;
 679        }
 680
 681        n = INTEL_PT_PKT_MAX_SZ - len;
 682        if (n > decoder->len)
 683                n = decoder->len;
 684        memcpy(buf + len, decoder->buf, n);
 685        len += n;
 686
 687        decoder->prev_pkt_ctx = decoder->pkt_ctx;
 688        ret = intel_pt_get_packet(buf, len, &decoder->packet, &decoder->pkt_ctx);
 689        if (ret < (int)old_len) {
 690                decoder->next_buf = decoder->buf;
 691                decoder->next_len = decoder->len;
 692                decoder->buf = buf;
 693                decoder->len = old_len;
 694                return intel_pt_bad_packet(decoder);
 695        }
 696
 697        decoder->next_buf = decoder->buf + (ret - old_len);
 698        decoder->next_len = decoder->len - (ret - old_len);
 699
 700        decoder->buf = buf;
 701        decoder->len = ret;
 702
 703        return ret;
 704}
 705
 706struct intel_pt_pkt_info {
 707        struct intel_pt_decoder   *decoder;
 708        struct intel_pt_pkt       packet;
 709        uint64_t                  pos;
 710        int                       pkt_len;
 711        int                       last_packet_type;
 712        void                      *data;
 713};
 714
 715typedef int (*intel_pt_pkt_cb_t)(struct intel_pt_pkt_info *pkt_info);
 716
 717/* Lookahead packets in current buffer */
 718static int intel_pt_pkt_lookahead(struct intel_pt_decoder *decoder,
 719                                  intel_pt_pkt_cb_t cb, void *data)
 720{
 721        struct intel_pt_pkt_info pkt_info;
 722        const unsigned char *buf = decoder->buf;
 723        enum intel_pt_pkt_ctx pkt_ctx = decoder->pkt_ctx;
 724        size_t len = decoder->len;
 725        int ret;
 726
 727        pkt_info.decoder          = decoder;
 728        pkt_info.pos              = decoder->pos;
 729        pkt_info.pkt_len          = decoder->pkt_step;
 730        pkt_info.last_packet_type = decoder->last_packet_type;
 731        pkt_info.data             = data;
 732
 733        while (1) {
 734                do {
 735                        pkt_info.pos += pkt_info.pkt_len;
 736                        buf          += pkt_info.pkt_len;
 737                        len          -= pkt_info.pkt_len;
 738
 739                        if (!len)
 740                                return INTEL_PT_NEED_MORE_BYTES;
 741
 742                        ret = intel_pt_get_packet(buf, len, &pkt_info.packet,
 743                                                  &pkt_ctx);
 744                        if (!ret)
 745                                return INTEL_PT_NEED_MORE_BYTES;
 746                        if (ret < 0)
 747                                return ret;
 748
 749                        pkt_info.pkt_len = ret;
 750                } while (pkt_info.packet.type == INTEL_PT_PAD);
 751
 752                ret = cb(&pkt_info);
 753                if (ret)
 754                        return 0;
 755
 756                pkt_info.last_packet_type = pkt_info.packet.type;
 757        }
 758}
 759
 760struct intel_pt_calc_cyc_to_tsc_info {
 761        uint64_t        cycle_cnt;
 762        unsigned int    cbr;
 763        uint32_t        last_mtc;
 764        uint64_t        ctc_timestamp;
 765        uint64_t        ctc_delta;
 766        uint64_t        tsc_timestamp;
 767        uint64_t        timestamp;
 768        bool            have_tma;
 769        bool            fixup_last_mtc;
 770        bool            from_mtc;
 771        double          cbr_cyc_to_tsc;
 772};
 773
 774/*
 775 * MTC provides a 8-bit slice of CTC but the TMA packet only provides the lower
 776 * 16 bits of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC
 777 * provided by the TMA packet. Fix-up the last_mtc calculated from the TMA
 778 * packet by copying the missing bits from the current MTC assuming the least
 779 * difference between the two, and that the current MTC comes after last_mtc.
 780 */
 781static void intel_pt_fixup_last_mtc(uint32_t mtc, int mtc_shift,
 782                                    uint32_t *last_mtc)
 783{
 784        uint32_t first_missing_bit = 1U << (16 - mtc_shift);
 785        uint32_t mask = ~(first_missing_bit - 1);
 786
 787        *last_mtc |= mtc & mask;
 788        if (*last_mtc >= mtc) {
 789                *last_mtc -= first_missing_bit;
 790                *last_mtc &= 0xff;
 791        }
 792}
 793
 794static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
 795{
 796        struct intel_pt_decoder *decoder = pkt_info->decoder;
 797        struct intel_pt_calc_cyc_to_tsc_info *data = pkt_info->data;
 798        uint64_t timestamp;
 799        double cyc_to_tsc;
 800        unsigned int cbr;
 801        uint32_t mtc, mtc_delta, ctc, fc, ctc_rem;
 802
 803        switch (pkt_info->packet.type) {
 804        case INTEL_PT_TNT:
 805        case INTEL_PT_TIP_PGE:
 806        case INTEL_PT_TIP:
 807        case INTEL_PT_FUP:
 808        case INTEL_PT_PSB:
 809        case INTEL_PT_PIP:
 810        case INTEL_PT_MODE_EXEC:
 811        case INTEL_PT_MODE_TSX:
 812        case INTEL_PT_PSBEND:
 813        case INTEL_PT_PAD:
 814        case INTEL_PT_VMCS:
 815        case INTEL_PT_MNT:
 816        case INTEL_PT_PTWRITE:
 817        case INTEL_PT_PTWRITE_IP:
 818        case INTEL_PT_BBP:
 819        case INTEL_PT_BIP:
 820        case INTEL_PT_BEP:
 821        case INTEL_PT_BEP_IP:
 822                return 0;
 823
 824        case INTEL_PT_MTC:
 825                if (!data->have_tma)
 826                        return 0;
 827
 828                mtc = pkt_info->packet.payload;
 829                if (decoder->mtc_shift > 8 && data->fixup_last_mtc) {
 830                        data->fixup_last_mtc = false;
 831                        intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
 832                                                &data->last_mtc);
 833                }
 834                if (mtc > data->last_mtc)
 835                        mtc_delta = mtc - data->last_mtc;
 836                else
 837                        mtc_delta = mtc + 256 - data->last_mtc;
 838                data->ctc_delta += mtc_delta << decoder->mtc_shift;
 839                data->last_mtc = mtc;
 840
 841                if (decoder->tsc_ctc_mult) {
 842                        timestamp = data->ctc_timestamp +
 843                                data->ctc_delta * decoder->tsc_ctc_mult;
 844                } else {
 845                        timestamp = data->ctc_timestamp +
 846                                multdiv(data->ctc_delta,
 847                                        decoder->tsc_ctc_ratio_n,
 848                                        decoder->tsc_ctc_ratio_d);
 849                }
 850
 851                if (timestamp < data->timestamp)
 852                        return 1;
 853
 854                if (pkt_info->last_packet_type != INTEL_PT_CYC) {
 855                        data->timestamp = timestamp;
 856                        return 0;
 857                }
 858
 859                break;
 860
 861        case INTEL_PT_TSC:
 862                /*
 863                 * For now, do not support using TSC packets - refer
 864                 * intel_pt_calc_cyc_to_tsc().
 865                 */
 866                if (data->from_mtc)
 867                        return 1;
 868                timestamp = pkt_info->packet.payload |
 869                            (data->timestamp & (0xffULL << 56));
 870                if (data->from_mtc && timestamp < data->timestamp &&
 871                    data->timestamp - timestamp < decoder->tsc_slip)
 872                        return 1;
 873                if (timestamp < data->timestamp)
 874                        timestamp += (1ULL << 56);
 875                if (pkt_info->last_packet_type != INTEL_PT_CYC) {
 876                        if (data->from_mtc)
 877                                return 1;
 878                        data->tsc_timestamp = timestamp;
 879                        data->timestamp = timestamp;
 880                        return 0;
 881                }
 882                break;
 883
 884        case INTEL_PT_TMA:
 885                if (data->from_mtc)
 886                        return 1;
 887
 888                if (!decoder->tsc_ctc_ratio_d)
 889                        return 0;
 890
 891                ctc = pkt_info->packet.payload;
 892                fc = pkt_info->packet.count;
 893                ctc_rem = ctc & decoder->ctc_rem_mask;
 894
 895                data->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
 896
 897                data->ctc_timestamp = data->tsc_timestamp - fc;
 898                if (decoder->tsc_ctc_mult) {
 899                        data->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
 900                } else {
 901                        data->ctc_timestamp -=
 902                                multdiv(ctc_rem, decoder->tsc_ctc_ratio_n,
 903                                        decoder->tsc_ctc_ratio_d);
 904                }
 905
 906                data->ctc_delta = 0;
 907                data->have_tma = true;
 908                data->fixup_last_mtc = true;
 909
 910                return 0;
 911
 912        case INTEL_PT_CYC:
 913                data->cycle_cnt += pkt_info->packet.payload;
 914                return 0;
 915
 916        case INTEL_PT_CBR:
 917                cbr = pkt_info->packet.payload;
 918                if (data->cbr && data->cbr != cbr)
 919                        return 1;
 920                data->cbr = cbr;
 921                data->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
 922                return 0;
 923
 924        case INTEL_PT_TIP_PGD:
 925        case INTEL_PT_TRACESTOP:
 926        case INTEL_PT_EXSTOP:
 927        case INTEL_PT_EXSTOP_IP:
 928        case INTEL_PT_MWAIT:
 929        case INTEL_PT_PWRE:
 930        case INTEL_PT_PWRX:
 931        case INTEL_PT_OVF:
 932        case INTEL_PT_BAD: /* Does not happen */
 933        default:
 934                return 1;
 935        }
 936
 937        if (!data->cbr && decoder->cbr) {
 938                data->cbr = decoder->cbr;
 939                data->cbr_cyc_to_tsc = decoder->cbr_cyc_to_tsc;
 940        }
 941
 942        if (!data->cycle_cnt)
 943                return 1;
 944
 945        cyc_to_tsc = (double)(timestamp - decoder->timestamp) / data->cycle_cnt;
 946
 947        if (data->cbr && cyc_to_tsc > data->cbr_cyc_to_tsc &&
 948            cyc_to_tsc / data->cbr_cyc_to_tsc > 1.25) {
 949                intel_pt_log("Timestamp: calculated %g TSC ticks per cycle too big (c.f. CBR-based value %g), pos " x64_fmt "\n",
 950                             cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
 951                return 1;
 952        }
 953
 954        decoder->calc_cyc_to_tsc = cyc_to_tsc;
 955        decoder->have_calc_cyc_to_tsc = true;
 956
 957        if (data->cbr) {
 958                intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. CBR-based value %g, pos " x64_fmt "\n",
 959                             cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
 960        } else {
 961                intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. unknown CBR-based value, pos " x64_fmt "\n",
 962                             cyc_to_tsc, pkt_info->pos);
 963        }
 964
 965        return 1;
 966}
 967
 968static void intel_pt_calc_cyc_to_tsc(struct intel_pt_decoder *decoder,
 969                                     bool from_mtc)
 970{
 971        struct intel_pt_calc_cyc_to_tsc_info data = {
 972                .cycle_cnt      = 0,
 973                .cbr            = 0,
 974                .last_mtc       = decoder->last_mtc,
 975                .ctc_timestamp  = decoder->ctc_timestamp,
 976                .ctc_delta      = decoder->ctc_delta,
 977                .tsc_timestamp  = decoder->tsc_timestamp,
 978                .timestamp      = decoder->timestamp,
 979                .have_tma       = decoder->have_tma,
 980                .fixup_last_mtc = decoder->fixup_last_mtc,
 981                .from_mtc       = from_mtc,
 982                .cbr_cyc_to_tsc = 0,
 983        };
 984
 985        /*
 986         * For now, do not support using TSC packets for at least the reasons:
 987         * 1) timing might have stopped
 988         * 2) TSC packets within PSB+ can slip against CYC packets
 989         */
 990        if (!from_mtc)
 991                return;
 992
 993        intel_pt_pkt_lookahead(decoder, intel_pt_calc_cyc_cb, &data);
 994}
 995
 996static int intel_pt_get_next_packet(struct intel_pt_decoder *decoder)
 997{
 998        int ret;
 999
1000        decoder->last_packet_type = decoder->packet.type;
1001
1002        do {
1003                decoder->pos += decoder->pkt_step;
1004                decoder->buf += decoder->pkt_step;
1005                decoder->len -= decoder->pkt_step;
1006
1007                if (!decoder->len) {
1008                        ret = intel_pt_get_next_data(decoder, false);
1009                        if (ret)
1010                                return ret;
1011                }
1012
1013                decoder->prev_pkt_ctx = decoder->pkt_ctx;
1014                ret = intel_pt_get_packet(decoder->buf, decoder->len,
1015                                          &decoder->packet, &decoder->pkt_ctx);
1016                if (ret == INTEL_PT_NEED_MORE_BYTES && BITS_PER_LONG == 32 &&
1017                    decoder->len < INTEL_PT_PKT_MAX_SZ && !decoder->next_buf) {
1018                        ret = intel_pt_get_split_packet(decoder);
1019                        if (ret < 0)
1020                                return ret;
1021                }
1022                if (ret <= 0)
1023                        return intel_pt_bad_packet(decoder);
1024
1025                decoder->pkt_len = ret;
1026                decoder->pkt_step = ret;
1027                intel_pt_decoder_log_packet(decoder);
1028        } while (decoder->packet.type == INTEL_PT_PAD);
1029
1030        return 0;
1031}
1032
1033static uint64_t intel_pt_next_period(struct intel_pt_decoder *decoder)
1034{
1035        uint64_t timestamp, masked_timestamp;
1036
1037        timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
1038        masked_timestamp = timestamp & decoder->period_mask;
1039        if (decoder->continuous_period) {
1040                if (masked_timestamp > decoder->last_masked_timestamp)
1041                        return 1;
1042        } else {
1043                timestamp += 1;
1044                masked_timestamp = timestamp & decoder->period_mask;
1045                if (masked_timestamp > decoder->last_masked_timestamp) {
1046                        decoder->last_masked_timestamp = masked_timestamp;
1047                        decoder->continuous_period = true;
1048                }
1049        }
1050
1051        if (masked_timestamp < decoder->last_masked_timestamp)
1052                return decoder->period_ticks;
1053
1054        return decoder->period_ticks - (timestamp - masked_timestamp);
1055}
1056
1057static uint64_t intel_pt_next_sample(struct intel_pt_decoder *decoder)
1058{
1059        switch (decoder->period_type) {
1060        case INTEL_PT_PERIOD_INSTRUCTIONS:
1061                return decoder->period - decoder->period_insn_cnt;
1062        case INTEL_PT_PERIOD_TICKS:
1063                return intel_pt_next_period(decoder);
1064        case INTEL_PT_PERIOD_NONE:
1065        case INTEL_PT_PERIOD_MTC:
1066        default:
1067                return 0;
1068        }
1069}
1070
1071static void intel_pt_sample_insn(struct intel_pt_decoder *decoder)
1072{
1073        uint64_t timestamp, masked_timestamp;
1074
1075        switch (decoder->period_type) {
1076        case INTEL_PT_PERIOD_INSTRUCTIONS:
1077                decoder->period_insn_cnt = 0;
1078                break;
1079        case INTEL_PT_PERIOD_TICKS:
1080                timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
1081                masked_timestamp = timestamp & decoder->period_mask;
1082                if (masked_timestamp > decoder->last_masked_timestamp)
1083                        decoder->last_masked_timestamp = masked_timestamp;
1084                else
1085                        decoder->last_masked_timestamp += decoder->period_ticks;
1086                break;
1087        case INTEL_PT_PERIOD_NONE:
1088        case INTEL_PT_PERIOD_MTC:
1089        default:
1090                break;
1091        }
1092
1093        decoder->state.type |= INTEL_PT_INSTRUCTION;
1094}
1095
1096static int intel_pt_walk_insn(struct intel_pt_decoder *decoder,
1097                              struct intel_pt_insn *intel_pt_insn, uint64_t ip)
1098{
1099        uint64_t max_insn_cnt, insn_cnt = 0;
1100        int err;
1101
1102        if (!decoder->mtc_insn)
1103                decoder->mtc_insn = true;
1104
1105        max_insn_cnt = intel_pt_next_sample(decoder);
1106
1107        err = decoder->walk_insn(intel_pt_insn, &insn_cnt, &decoder->ip, ip,
1108                                 max_insn_cnt, decoder->data);
1109
1110        decoder->tot_insn_cnt += insn_cnt;
1111        decoder->timestamp_insn_cnt += insn_cnt;
1112        decoder->sample_insn_cnt += insn_cnt;
1113        decoder->period_insn_cnt += insn_cnt;
1114
1115        if (err) {
1116                decoder->no_progress = 0;
1117                decoder->pkt_state = INTEL_PT_STATE_ERR2;
1118                intel_pt_log_at("ERROR: Failed to get instruction",
1119                                decoder->ip);
1120                if (err == -ENOENT)
1121                        return -ENOLINK;
1122                return -EILSEQ;
1123        }
1124
1125        if (ip && decoder->ip == ip) {
1126                err = -EAGAIN;
1127                goto out;
1128        }
1129
1130        if (max_insn_cnt && insn_cnt >= max_insn_cnt)
1131                intel_pt_sample_insn(decoder);
1132
1133        if (intel_pt_insn->branch == INTEL_PT_BR_NO_BRANCH) {
1134                decoder->state.type = INTEL_PT_INSTRUCTION;
1135                decoder->state.from_ip = decoder->ip;
1136                decoder->state.to_ip = 0;
1137                decoder->ip += intel_pt_insn->length;
1138                err = INTEL_PT_RETURN;
1139                goto out;
1140        }
1141
1142        if (intel_pt_insn->op == INTEL_PT_OP_CALL) {
1143                /* Zero-length calls are excluded */
1144                if (intel_pt_insn->branch != INTEL_PT_BR_UNCONDITIONAL ||
1145                    intel_pt_insn->rel) {
1146                        err = intel_pt_push(&decoder->stack, decoder->ip +
1147                                            intel_pt_insn->length);
1148                        if (err)
1149                                goto out;
1150                }
1151        } else if (intel_pt_insn->op == INTEL_PT_OP_RET) {
1152                decoder->ret_addr = intel_pt_pop(&decoder->stack);
1153        }
1154
1155        if (intel_pt_insn->branch == INTEL_PT_BR_UNCONDITIONAL) {
1156                int cnt = decoder->no_progress++;
1157
1158                decoder->state.from_ip = decoder->ip;
1159                decoder->ip += intel_pt_insn->length +
1160                                intel_pt_insn->rel;
1161                decoder->state.to_ip = decoder->ip;
1162                err = INTEL_PT_RETURN;
1163
1164                /*
1165                 * Check for being stuck in a loop.  This can happen if a
1166                 * decoder error results in the decoder erroneously setting the
1167                 * ip to an address that is itself in an infinite loop that
1168                 * consumes no packets.  When that happens, there must be an
1169                 * unconditional branch.
1170                 */
1171                if (cnt) {
1172                        if (cnt == 1) {
1173                                decoder->stuck_ip = decoder->state.to_ip;
1174                                decoder->stuck_ip_prd = 1;
1175                                decoder->stuck_ip_cnt = 1;
1176                        } else if (cnt > decoder->max_loops ||
1177                                   decoder->state.to_ip == decoder->stuck_ip) {
1178                                intel_pt_log_at("ERROR: Never-ending loop",
1179                                                decoder->state.to_ip);
1180                                decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1181                                err = -ELOOP;
1182                                goto out;
1183                        } else if (!--decoder->stuck_ip_cnt) {
1184                                decoder->stuck_ip_prd += 1;
1185                                decoder->stuck_ip_cnt = decoder->stuck_ip_prd;
1186                                decoder->stuck_ip = decoder->state.to_ip;
1187                        }
1188                }
1189                goto out_no_progress;
1190        }
1191out:
1192        decoder->no_progress = 0;
1193out_no_progress:
1194        decoder->state.insn_op = intel_pt_insn->op;
1195        decoder->state.insn_len = intel_pt_insn->length;
1196        memcpy(decoder->state.insn, intel_pt_insn->buf,
1197               INTEL_PT_INSN_BUF_SZ);
1198
1199        if (decoder->tx_flags & INTEL_PT_IN_TX)
1200                decoder->state.flags |= INTEL_PT_IN_TX;
1201
1202        return err;
1203}
1204
1205static bool intel_pt_fup_event(struct intel_pt_decoder *decoder)
1206{
1207        bool ret = false;
1208
1209        if (decoder->set_fup_tx_flags) {
1210                decoder->set_fup_tx_flags = false;
1211                decoder->tx_flags = decoder->fup_tx_flags;
1212                decoder->state.type = INTEL_PT_TRANSACTION;
1213                if (decoder->fup_tx_flags & INTEL_PT_ABORT_TX)
1214                        decoder->state.type |= INTEL_PT_BRANCH;
1215                decoder->state.from_ip = decoder->ip;
1216                decoder->state.to_ip = 0;
1217                decoder->state.flags = decoder->fup_tx_flags;
1218                return true;
1219        }
1220        if (decoder->set_fup_ptw) {
1221                decoder->set_fup_ptw = false;
1222                decoder->state.type = INTEL_PT_PTW;
1223                decoder->state.flags |= INTEL_PT_FUP_IP;
1224                decoder->state.from_ip = decoder->ip;
1225                decoder->state.to_ip = 0;
1226                decoder->state.ptw_payload = decoder->fup_ptw_payload;
1227                return true;
1228        }
1229        if (decoder->set_fup_mwait) {
1230                decoder->set_fup_mwait = false;
1231                decoder->state.type = INTEL_PT_MWAIT_OP;
1232                decoder->state.from_ip = decoder->ip;
1233                decoder->state.to_ip = 0;
1234                decoder->state.mwait_payload = decoder->fup_mwait_payload;
1235                ret = true;
1236        }
1237        if (decoder->set_fup_pwre) {
1238                decoder->set_fup_pwre = false;
1239                decoder->state.type |= INTEL_PT_PWR_ENTRY;
1240                decoder->state.type &= ~INTEL_PT_BRANCH;
1241                decoder->state.from_ip = decoder->ip;
1242                decoder->state.to_ip = 0;
1243                decoder->state.pwre_payload = decoder->fup_pwre_payload;
1244                ret = true;
1245        }
1246        if (decoder->set_fup_exstop) {
1247                decoder->set_fup_exstop = false;
1248                decoder->state.type |= INTEL_PT_EX_STOP;
1249                decoder->state.type &= ~INTEL_PT_BRANCH;
1250                decoder->state.flags |= INTEL_PT_FUP_IP;
1251                decoder->state.from_ip = decoder->ip;
1252                decoder->state.to_ip = 0;
1253                ret = true;
1254        }
1255        if (decoder->set_fup_bep) {
1256                decoder->set_fup_bep = false;
1257                decoder->state.type |= INTEL_PT_BLK_ITEMS;
1258                decoder->state.type &= ~INTEL_PT_BRANCH;
1259                decoder->state.from_ip = decoder->ip;
1260                decoder->state.to_ip = 0;
1261                ret = true;
1262        }
1263        return ret;
1264}
1265
1266static inline bool intel_pt_fup_with_nlip(struct intel_pt_decoder *decoder,
1267                                          struct intel_pt_insn *intel_pt_insn,
1268                                          uint64_t ip, int err)
1269{
1270        return decoder->flags & INTEL_PT_FUP_WITH_NLIP && !err &&
1271               intel_pt_insn->branch == INTEL_PT_BR_INDIRECT &&
1272               ip == decoder->ip + intel_pt_insn->length;
1273}
1274
1275static int intel_pt_walk_fup(struct intel_pt_decoder *decoder)
1276{
1277        struct intel_pt_insn intel_pt_insn;
1278        uint64_t ip;
1279        int err;
1280
1281        ip = decoder->last_ip;
1282
1283        while (1) {
1284                err = intel_pt_walk_insn(decoder, &intel_pt_insn, ip);
1285                if (err == INTEL_PT_RETURN)
1286                        return 0;
1287                if (err == -EAGAIN ||
1288                    intel_pt_fup_with_nlip(decoder, &intel_pt_insn, ip, err)) {
1289                        bool no_tip = decoder->pkt_state != INTEL_PT_STATE_FUP;
1290
1291                        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1292                        if (intel_pt_fup_event(decoder) && no_tip)
1293                                return 0;
1294                        return -EAGAIN;
1295                }
1296                decoder->set_fup_tx_flags = false;
1297                if (err)
1298                        return err;
1299
1300                if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1301                        intel_pt_log_at("ERROR: Unexpected indirect branch",
1302                                        decoder->ip);
1303                        decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1304                        return -ENOENT;
1305                }
1306
1307                if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1308                        intel_pt_log_at("ERROR: Unexpected conditional branch",
1309                                        decoder->ip);
1310                        decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1311                        return -ENOENT;
1312                }
1313
1314                intel_pt_bug(decoder);
1315        }
1316}
1317
1318static int intel_pt_walk_tip(struct intel_pt_decoder *decoder)
1319{
1320        struct intel_pt_insn intel_pt_insn;
1321        int err;
1322
1323        err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1324        if (err == INTEL_PT_RETURN &&
1325            decoder->pgd_ip &&
1326            decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1327            (decoder->state.type & INTEL_PT_BRANCH) &&
1328            decoder->pgd_ip(decoder->state.to_ip, decoder->data)) {
1329                /* Unconditional branch leaving filter region */
1330                decoder->no_progress = 0;
1331                decoder->pge = false;
1332                decoder->continuous_period = false;
1333                decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1334                decoder->state.type |= INTEL_PT_TRACE_END;
1335                intel_pt_update_nr(decoder);
1336                return 0;
1337        }
1338        if (err == INTEL_PT_RETURN)
1339                return 0;
1340        if (err)
1341                return err;
1342
1343        intel_pt_update_nr(decoder);
1344
1345        if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1346                if (decoder->pkt_state == INTEL_PT_STATE_TIP_PGD) {
1347                        decoder->pge = false;
1348                        decoder->continuous_period = false;
1349                        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1350                        decoder->state.from_ip = decoder->ip;
1351                        if (decoder->packet.count == 0) {
1352                                decoder->state.to_ip = 0;
1353                        } else {
1354                                decoder->state.to_ip = decoder->last_ip;
1355                                decoder->ip = decoder->last_ip;
1356                        }
1357                        decoder->state.type |= INTEL_PT_TRACE_END;
1358                } else {
1359                        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1360                        decoder->state.from_ip = decoder->ip;
1361                        if (decoder->packet.count == 0) {
1362                                decoder->state.to_ip = 0;
1363                        } else {
1364                                decoder->state.to_ip = decoder->last_ip;
1365                                decoder->ip = decoder->last_ip;
1366                        }
1367                }
1368                return 0;
1369        }
1370
1371        if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1372                uint64_t to_ip = decoder->ip + intel_pt_insn.length +
1373                                 intel_pt_insn.rel;
1374
1375                if (decoder->pgd_ip &&
1376                    decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1377                    decoder->pgd_ip(to_ip, decoder->data)) {
1378                        /* Conditional branch leaving filter region */
1379                        decoder->pge = false;
1380                        decoder->continuous_period = false;
1381                        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1382                        decoder->ip = to_ip;
1383                        decoder->state.from_ip = decoder->ip;
1384                        decoder->state.to_ip = to_ip;
1385                        decoder->state.type |= INTEL_PT_TRACE_END;
1386                        return 0;
1387                }
1388                intel_pt_log_at("ERROR: Conditional branch when expecting indirect branch",
1389                                decoder->ip);
1390                decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1391                return -ENOENT;
1392        }
1393
1394        return intel_pt_bug(decoder);
1395}
1396
1397static int intel_pt_walk_tnt(struct intel_pt_decoder *decoder)
1398{
1399        struct intel_pt_insn intel_pt_insn;
1400        int err;
1401
1402        while (1) {
1403                err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1404                if (err == INTEL_PT_RETURN)
1405                        return 0;
1406                if (err)
1407                        return err;
1408
1409                if (intel_pt_insn.op == INTEL_PT_OP_RET) {
1410                        if (!decoder->return_compression) {
1411                                intel_pt_log_at("ERROR: RET when expecting conditional branch",
1412                                                decoder->ip);
1413                                decoder->pkt_state = INTEL_PT_STATE_ERR3;
1414                                return -ENOENT;
1415                        }
1416                        if (!decoder->ret_addr) {
1417                                intel_pt_log_at("ERROR: Bad RET compression (stack empty)",
1418                                                decoder->ip);
1419                                decoder->pkt_state = INTEL_PT_STATE_ERR3;
1420                                return -ENOENT;
1421                        }
1422                        if (!(decoder->tnt.payload & BIT63)) {
1423                                intel_pt_log_at("ERROR: Bad RET compression (TNT=N)",
1424                                                decoder->ip);
1425                                decoder->pkt_state = INTEL_PT_STATE_ERR3;
1426                                return -ENOENT;
1427                        }
1428                        decoder->tnt.count -= 1;
1429                        if (decoder->tnt.count)
1430                                decoder->pkt_state = INTEL_PT_STATE_TNT_CONT;
1431                        else
1432                                decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1433                        decoder->tnt.payload <<= 1;
1434                        decoder->state.from_ip = decoder->ip;
1435                        decoder->ip = decoder->ret_addr;
1436                        decoder->state.to_ip = decoder->ip;
1437                        return 0;
1438                }
1439
1440                if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1441                        /* Handle deferred TIPs */
1442                        err = intel_pt_get_next_packet(decoder);
1443                        if (err)
1444                                return err;
1445                        if (decoder->packet.type != INTEL_PT_TIP ||
1446                            decoder->packet.count == 0) {
1447                                intel_pt_log_at("ERROR: Missing deferred TIP for indirect branch",
1448                                                decoder->ip);
1449                                decoder->pkt_state = INTEL_PT_STATE_ERR3;
1450                                decoder->pkt_step = 0;
1451                                return -ENOENT;
1452                        }
1453                        intel_pt_set_last_ip(decoder);
1454                        decoder->state.from_ip = decoder->ip;
1455                        decoder->state.to_ip = decoder->last_ip;
1456                        decoder->ip = decoder->last_ip;
1457                        intel_pt_update_nr(decoder);
1458                        return 0;
1459                }
1460
1461                if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1462                        decoder->tnt.count -= 1;
1463                        if (decoder->tnt.count)
1464                                decoder->pkt_state = INTEL_PT_STATE_TNT_CONT;
1465                        else
1466                                decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1467                        if (decoder->tnt.payload & BIT63) {
1468                                decoder->tnt.payload <<= 1;
1469                                decoder->state.from_ip = decoder->ip;
1470                                decoder->ip += intel_pt_insn.length +
1471                                               intel_pt_insn.rel;
1472                                decoder->state.to_ip = decoder->ip;
1473                                return 0;
1474                        }
1475                        /* Instruction sample for a non-taken branch */
1476                        if (decoder->state.type & INTEL_PT_INSTRUCTION) {
1477                                decoder->tnt.payload <<= 1;
1478                                decoder->state.type = INTEL_PT_INSTRUCTION;
1479                                decoder->state.from_ip = decoder->ip;
1480                                decoder->state.to_ip = 0;
1481                                decoder->ip += intel_pt_insn.length;
1482                                return 0;
1483                        }
1484                        decoder->sample_cyc = false;
1485                        decoder->ip += intel_pt_insn.length;
1486                        if (!decoder->tnt.count) {
1487                                intel_pt_update_sample_time(decoder);
1488                                return -EAGAIN;
1489                        }
1490                        decoder->tnt.payload <<= 1;
1491                        continue;
1492                }
1493
1494                return intel_pt_bug(decoder);
1495        }
1496}
1497
1498static int intel_pt_mode_tsx(struct intel_pt_decoder *decoder, bool *no_tip)
1499{
1500        unsigned int fup_tx_flags;
1501        int err;
1502
1503        fup_tx_flags = decoder->packet.payload &
1504                       (INTEL_PT_IN_TX | INTEL_PT_ABORT_TX);
1505        err = intel_pt_get_next_packet(decoder);
1506        if (err)
1507                return err;
1508        if (decoder->packet.type == INTEL_PT_FUP) {
1509                decoder->fup_tx_flags = fup_tx_flags;
1510                decoder->set_fup_tx_flags = true;
1511                if (!(decoder->fup_tx_flags & INTEL_PT_ABORT_TX))
1512                        *no_tip = true;
1513        } else {
1514                intel_pt_log_at("ERROR: Missing FUP after MODE.TSX",
1515                                decoder->pos);
1516                intel_pt_update_in_tx(decoder);
1517        }
1518        return 0;
1519}
1520
1521static uint64_t intel_pt_8b_tsc(uint64_t timestamp, uint64_t ref_timestamp)
1522{
1523        timestamp |= (ref_timestamp & (0xffULL << 56));
1524
1525        if (timestamp < ref_timestamp) {
1526                if (ref_timestamp - timestamp > (1ULL << 55))
1527                        timestamp += (1ULL << 56);
1528        } else {
1529                if (timestamp - ref_timestamp > (1ULL << 55))
1530                        timestamp -= (1ULL << 56);
1531        }
1532
1533        return timestamp;
1534}
1535
1536/* For use only when decoder->vm_time_correlation is true */
1537static bool intel_pt_time_in_range(struct intel_pt_decoder *decoder,
1538                                   uint64_t timestamp)
1539{
1540        uint64_t max_timestamp = decoder->buf_timestamp;
1541
1542        if (!max_timestamp) {
1543                max_timestamp = decoder->last_reliable_timestamp +
1544                                0x400000000ULL;
1545        }
1546        return timestamp >= decoder->last_reliable_timestamp &&
1547               timestamp < decoder->buf_timestamp;
1548}
1549
1550static void intel_pt_calc_tsc_timestamp(struct intel_pt_decoder *decoder)
1551{
1552        uint64_t timestamp;
1553        bool bad = false;
1554
1555        decoder->have_tma = false;
1556
1557        if (decoder->ref_timestamp) {
1558                timestamp = intel_pt_8b_tsc(decoder->packet.payload,
1559                                            decoder->ref_timestamp);
1560                decoder->tsc_timestamp = timestamp;
1561                decoder->timestamp = timestamp;
1562                decoder->ref_timestamp = 0;
1563                decoder->timestamp_insn_cnt = 0;
1564        } else if (decoder->timestamp) {
1565                timestamp = decoder->packet.payload |
1566                            (decoder->timestamp & (0xffULL << 56));
1567                decoder->tsc_timestamp = timestamp;
1568                if (timestamp < decoder->timestamp &&
1569                    decoder->timestamp - timestamp < decoder->tsc_slip) {
1570                        intel_pt_log_to("Suppressing backwards timestamp",
1571                                        timestamp);
1572                        timestamp = decoder->timestamp;
1573                }
1574                if (timestamp < decoder->timestamp) {
1575                        if (!decoder->buf_timestamp ||
1576                            (timestamp + (1ULL << 56) < decoder->buf_timestamp)) {
1577                                intel_pt_log_to("Wraparound timestamp", timestamp);
1578                                timestamp += (1ULL << 56);
1579                                decoder->tsc_timestamp = timestamp;
1580                        } else {
1581                                intel_pt_log_to("Suppressing bad timestamp", timestamp);
1582                                timestamp = decoder->timestamp;
1583                                bad = true;
1584                        }
1585                }
1586                if (decoder->vm_time_correlation &&
1587                    (bad || !intel_pt_time_in_range(decoder, timestamp)) &&
1588                    intel_pt_print_once(decoder, INTEL_PT_PRT_ONCE_ERANGE))
1589                        p_log("Timestamp out of range");
1590                decoder->timestamp = timestamp;
1591                decoder->timestamp_insn_cnt = 0;
1592        }
1593
1594        if (decoder->last_packet_type == INTEL_PT_CYC) {
1595                decoder->cyc_ref_timestamp = decoder->timestamp;
1596                decoder->cycle_cnt = 0;
1597                decoder->have_calc_cyc_to_tsc = false;
1598                intel_pt_calc_cyc_to_tsc(decoder, false);
1599        }
1600
1601        intel_pt_log_to("Setting timestamp", decoder->timestamp);
1602}
1603
1604static int intel_pt_overflow(struct intel_pt_decoder *decoder)
1605{
1606        intel_pt_log("ERROR: Buffer overflow\n");
1607        intel_pt_clear_tx_flags(decoder);
1608        intel_pt_set_nr(decoder);
1609        decoder->timestamp_insn_cnt = 0;
1610        decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1611        decoder->overflow = true;
1612        return -EOVERFLOW;
1613}
1614
1615static inline void intel_pt_mtc_cyc_cnt_pge(struct intel_pt_decoder *decoder)
1616{
1617        if (decoder->have_cyc)
1618                return;
1619
1620        decoder->cyc_cnt_timestamp = decoder->timestamp;
1621        decoder->base_cyc_cnt = decoder->tot_cyc_cnt;
1622}
1623
1624static inline void intel_pt_mtc_cyc_cnt_cbr(struct intel_pt_decoder *decoder)
1625{
1626        decoder->tsc_to_cyc = decoder->cbr / decoder->max_non_turbo_ratio_fp;
1627
1628        if (decoder->pge)
1629                intel_pt_mtc_cyc_cnt_pge(decoder);
1630}
1631
1632static inline void intel_pt_mtc_cyc_cnt_upd(struct intel_pt_decoder *decoder)
1633{
1634        uint64_t tot_cyc_cnt, tsc_delta;
1635
1636        if (decoder->have_cyc)
1637                return;
1638
1639        decoder->sample_cyc = true;
1640
1641        if (!decoder->pge || decoder->timestamp <= decoder->cyc_cnt_timestamp)
1642                return;
1643
1644        tsc_delta = decoder->timestamp - decoder->cyc_cnt_timestamp;
1645        tot_cyc_cnt = tsc_delta * decoder->tsc_to_cyc + decoder->base_cyc_cnt;
1646
1647        if (tot_cyc_cnt > decoder->tot_cyc_cnt)
1648                decoder->tot_cyc_cnt = tot_cyc_cnt;
1649}
1650
1651static void intel_pt_calc_tma(struct intel_pt_decoder *decoder)
1652{
1653        uint32_t ctc = decoder->packet.payload;
1654        uint32_t fc = decoder->packet.count;
1655        uint32_t ctc_rem = ctc & decoder->ctc_rem_mask;
1656
1657        if (!decoder->tsc_ctc_ratio_d)
1658                return;
1659
1660        if (decoder->pge && !decoder->in_psb)
1661                intel_pt_mtc_cyc_cnt_pge(decoder);
1662        else
1663                intel_pt_mtc_cyc_cnt_upd(decoder);
1664
1665        decoder->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
1666        decoder->last_ctc = ctc - ctc_rem;
1667        decoder->ctc_timestamp = decoder->tsc_timestamp - fc;
1668        if (decoder->tsc_ctc_mult) {
1669                decoder->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
1670        } else {
1671                decoder->ctc_timestamp -= multdiv(ctc_rem,
1672                                                  decoder->tsc_ctc_ratio_n,
1673                                                  decoder->tsc_ctc_ratio_d);
1674        }
1675        decoder->ctc_delta = 0;
1676        decoder->have_tma = true;
1677        decoder->fixup_last_mtc = true;
1678        intel_pt_log("CTC timestamp " x64_fmt " last MTC %#x  CTC rem %#x\n",
1679                     decoder->ctc_timestamp, decoder->last_mtc, ctc_rem);
1680}
1681
1682static void intel_pt_calc_mtc_timestamp(struct intel_pt_decoder *decoder)
1683{
1684        uint64_t timestamp;
1685        uint32_t mtc, mtc_delta;
1686
1687        if (!decoder->have_tma)
1688                return;
1689
1690        mtc = decoder->packet.payload;
1691
1692        if (decoder->mtc_shift > 8 && decoder->fixup_last_mtc) {
1693                decoder->fixup_last_mtc = false;
1694                intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
1695                                        &decoder->last_mtc);
1696        }
1697
1698        if (mtc > decoder->last_mtc)
1699                mtc_delta = mtc - decoder->last_mtc;
1700        else
1701                mtc_delta = mtc + 256 - decoder->last_mtc;
1702
1703        decoder->ctc_delta += mtc_delta << decoder->mtc_shift;
1704
1705        if (decoder->tsc_ctc_mult) {
1706                timestamp = decoder->ctc_timestamp +
1707                            decoder->ctc_delta * decoder->tsc_ctc_mult;
1708        } else {
1709                timestamp = decoder->ctc_timestamp +
1710                            multdiv(decoder->ctc_delta,
1711                                    decoder->tsc_ctc_ratio_n,
1712                                    decoder->tsc_ctc_ratio_d);
1713        }
1714
1715        if (timestamp < decoder->timestamp)
1716                intel_pt_log("Suppressing MTC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1717                             timestamp, decoder->timestamp);
1718        else
1719                decoder->timestamp = timestamp;
1720
1721        intel_pt_mtc_cyc_cnt_upd(decoder);
1722
1723        decoder->timestamp_insn_cnt = 0;
1724        decoder->last_mtc = mtc;
1725
1726        if (decoder->last_packet_type == INTEL_PT_CYC) {
1727                decoder->cyc_ref_timestamp = decoder->timestamp;
1728                decoder->cycle_cnt = 0;
1729                decoder->have_calc_cyc_to_tsc = false;
1730                intel_pt_calc_cyc_to_tsc(decoder, true);
1731        }
1732
1733        intel_pt_log_to("Setting timestamp", decoder->timestamp);
1734}
1735
1736static void intel_pt_calc_cbr(struct intel_pt_decoder *decoder)
1737{
1738        unsigned int cbr = decoder->packet.payload & 0xff;
1739
1740        decoder->cbr_payload = decoder->packet.payload;
1741
1742        if (decoder->cbr == cbr)
1743                return;
1744
1745        decoder->cbr = cbr;
1746        decoder->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
1747
1748        intel_pt_mtc_cyc_cnt_cbr(decoder);
1749}
1750
1751static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder)
1752{
1753        uint64_t timestamp = decoder->cyc_ref_timestamp;
1754
1755        decoder->have_cyc = true;
1756
1757        decoder->cycle_cnt += decoder->packet.payload;
1758        if (decoder->pge)
1759                decoder->tot_cyc_cnt += decoder->packet.payload;
1760        decoder->sample_cyc = true;
1761
1762        if (!decoder->cyc_ref_timestamp)
1763                return;
1764
1765        if (decoder->have_calc_cyc_to_tsc)
1766                timestamp += decoder->cycle_cnt * decoder->calc_cyc_to_tsc;
1767        else if (decoder->cbr)
1768                timestamp += decoder->cycle_cnt * decoder->cbr_cyc_to_tsc;
1769        else
1770                return;
1771
1772        if (timestamp < decoder->timestamp)
1773                intel_pt_log("Suppressing CYC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1774                             timestamp, decoder->timestamp);
1775        else
1776                decoder->timestamp = timestamp;
1777
1778        decoder->timestamp_insn_cnt = 0;
1779
1780        intel_pt_log_to("Setting timestamp", decoder->timestamp);
1781}
1782
1783static void intel_pt_bbp(struct intel_pt_decoder *decoder)
1784{
1785        if (decoder->prev_pkt_ctx == INTEL_PT_NO_CTX) {
1786                memset(decoder->state.items.mask, 0, sizeof(decoder->state.items.mask));
1787                decoder->state.items.is_32_bit = false;
1788        }
1789        decoder->blk_type = decoder->packet.payload;
1790        decoder->blk_type_pos = intel_pt_blk_type_pos(decoder->blk_type);
1791        if (decoder->blk_type == INTEL_PT_GP_REGS)
1792                decoder->state.items.is_32_bit = decoder->packet.count;
1793        if (decoder->blk_type_pos < 0) {
1794                intel_pt_log("WARNING: Unknown block type %u\n",
1795                             decoder->blk_type);
1796        } else if (decoder->state.items.mask[decoder->blk_type_pos]) {
1797                intel_pt_log("WARNING: Duplicate block type %u\n",
1798                             decoder->blk_type);
1799        }
1800}
1801
1802static void intel_pt_bip(struct intel_pt_decoder *decoder)
1803{
1804        uint32_t id = decoder->packet.count;
1805        uint32_t bit = 1 << id;
1806        int pos = decoder->blk_type_pos;
1807
1808        if (pos < 0 || id >= INTEL_PT_BLK_ITEM_ID_CNT) {
1809                intel_pt_log("WARNING: Unknown block item %u type %d\n",
1810                             id, decoder->blk_type);
1811                return;
1812        }
1813
1814        if (decoder->state.items.mask[pos] & bit) {
1815                intel_pt_log("WARNING: Duplicate block item %u type %d\n",
1816                             id, decoder->blk_type);
1817        }
1818
1819        decoder->state.items.mask[pos] |= bit;
1820        decoder->state.items.val[pos][id] = decoder->packet.payload;
1821}
1822
1823/* Walk PSB+ packets when already in sync. */
1824static int intel_pt_walk_psbend(struct intel_pt_decoder *decoder)
1825{
1826        int err;
1827
1828        decoder->in_psb = true;
1829
1830        while (1) {
1831                err = intel_pt_get_next_packet(decoder);
1832                if (err)
1833                        goto out;
1834
1835                switch (decoder->packet.type) {
1836                case INTEL_PT_PSBEND:
1837                        err = 0;
1838                        goto out;
1839
1840                case INTEL_PT_TIP_PGD:
1841                case INTEL_PT_TIP_PGE:
1842                case INTEL_PT_TIP:
1843                case INTEL_PT_TNT:
1844                case INTEL_PT_TRACESTOP:
1845                case INTEL_PT_BAD:
1846                case INTEL_PT_PSB:
1847                case INTEL_PT_PTWRITE:
1848                case INTEL_PT_PTWRITE_IP:
1849                case INTEL_PT_EXSTOP:
1850                case INTEL_PT_EXSTOP_IP:
1851                case INTEL_PT_MWAIT:
1852                case INTEL_PT_PWRE:
1853                case INTEL_PT_PWRX:
1854                case INTEL_PT_BBP:
1855                case INTEL_PT_BIP:
1856                case INTEL_PT_BEP:
1857                case INTEL_PT_BEP_IP:
1858                        decoder->have_tma = false;
1859                        intel_pt_log("ERROR: Unexpected packet\n");
1860                        err = -EAGAIN;
1861                        goto out;
1862
1863                case INTEL_PT_OVF:
1864                        err = intel_pt_overflow(decoder);
1865                        goto out;
1866
1867                case INTEL_PT_TSC:
1868                        intel_pt_calc_tsc_timestamp(decoder);
1869                        break;
1870
1871                case INTEL_PT_TMA:
1872                        intel_pt_calc_tma(decoder);
1873                        break;
1874
1875                case INTEL_PT_CBR:
1876                        intel_pt_calc_cbr(decoder);
1877                        break;
1878
1879                case INTEL_PT_MODE_EXEC:
1880                        decoder->exec_mode = decoder->packet.payload;
1881                        break;
1882
1883                case INTEL_PT_PIP:
1884                        intel_pt_set_pip(decoder);
1885                        break;
1886
1887                case INTEL_PT_FUP:
1888                        decoder->pge = true;
1889                        if (decoder->packet.count) {
1890                                intel_pt_set_last_ip(decoder);
1891                                decoder->psb_ip = decoder->last_ip;
1892                        }
1893                        break;
1894
1895                case INTEL_PT_MODE_TSX:
1896                        intel_pt_update_in_tx(decoder);
1897                        break;
1898
1899                case INTEL_PT_MTC:
1900                        intel_pt_calc_mtc_timestamp(decoder);
1901                        if (decoder->period_type == INTEL_PT_PERIOD_MTC)
1902                                decoder->state.type |= INTEL_PT_INSTRUCTION;
1903                        break;
1904
1905                case INTEL_PT_CYC:
1906                        intel_pt_calc_cyc_timestamp(decoder);
1907                        break;
1908
1909                case INTEL_PT_VMCS:
1910                case INTEL_PT_MNT:
1911                case INTEL_PT_PAD:
1912                default:
1913                        break;
1914                }
1915        }
1916out:
1917        decoder->in_psb = false;
1918
1919        return err;
1920}
1921
1922static int intel_pt_walk_fup_tip(struct intel_pt_decoder *decoder)
1923{
1924        int err;
1925
1926        if (decoder->tx_flags & INTEL_PT_ABORT_TX) {
1927                decoder->tx_flags = 0;
1928                decoder->state.flags &= ~INTEL_PT_IN_TX;
1929                decoder->state.flags |= INTEL_PT_ABORT_TX;
1930        } else {
1931                decoder->state.flags |= INTEL_PT_ASYNC;
1932        }
1933
1934        while (1) {
1935                err = intel_pt_get_next_packet(decoder);
1936                if (err)
1937                        return err;
1938
1939                switch (decoder->packet.type) {
1940                case INTEL_PT_TNT:
1941                case INTEL_PT_FUP:
1942                case INTEL_PT_TRACESTOP:
1943                case INTEL_PT_PSB:
1944                case INTEL_PT_TSC:
1945                case INTEL_PT_TMA:
1946                case INTEL_PT_MODE_TSX:
1947                case INTEL_PT_BAD:
1948                case INTEL_PT_PSBEND:
1949                case INTEL_PT_PTWRITE:
1950                case INTEL_PT_PTWRITE_IP:
1951                case INTEL_PT_EXSTOP:
1952                case INTEL_PT_EXSTOP_IP:
1953                case INTEL_PT_MWAIT:
1954                case INTEL_PT_PWRE:
1955                case INTEL_PT_PWRX:
1956                case INTEL_PT_BBP:
1957                case INTEL_PT_BIP:
1958                case INTEL_PT_BEP:
1959                case INTEL_PT_BEP_IP:
1960                        intel_pt_log("ERROR: Missing TIP after FUP\n");
1961                        decoder->pkt_state = INTEL_PT_STATE_ERR3;
1962                        decoder->pkt_step = 0;
1963                        return -ENOENT;
1964
1965                case INTEL_PT_CBR:
1966                        intel_pt_calc_cbr(decoder);
1967                        break;
1968
1969                case INTEL_PT_OVF:
1970                        return intel_pt_overflow(decoder);
1971
1972                case INTEL_PT_TIP_PGD:
1973                        decoder->state.from_ip = decoder->ip;
1974                        if (decoder->packet.count == 0) {
1975                                decoder->state.to_ip = 0;
1976                        } else {
1977                                intel_pt_set_ip(decoder);
1978                                decoder->state.to_ip = decoder->ip;
1979                        }
1980                        decoder->pge = false;
1981                        decoder->continuous_period = false;
1982                        decoder->state.type |= INTEL_PT_TRACE_END;
1983                        intel_pt_update_nr(decoder);
1984                        return 0;
1985
1986                case INTEL_PT_TIP_PGE:
1987                        decoder->pge = true;
1988                        intel_pt_log("Omitting PGE ip " x64_fmt "\n",
1989                                     decoder->ip);
1990                        decoder->state.from_ip = 0;
1991                        if (decoder->packet.count == 0) {
1992                                decoder->state.to_ip = 0;
1993                        } else {
1994                                intel_pt_set_ip(decoder);
1995                                decoder->state.to_ip = decoder->ip;
1996                        }
1997                        decoder->state.type |= INTEL_PT_TRACE_BEGIN;
1998                        intel_pt_mtc_cyc_cnt_pge(decoder);
1999                        intel_pt_set_nr(decoder);
2000                        return 0;
2001
2002                case INTEL_PT_TIP:
2003                        decoder->state.from_ip = decoder->ip;
2004                        if (decoder->packet.count == 0) {
2005                                decoder->state.to_ip = 0;
2006                        } else {
2007                                intel_pt_set_ip(decoder);
2008                                decoder->state.to_ip = decoder->ip;
2009                        }
2010                        intel_pt_update_nr(decoder);
2011                        return 0;
2012
2013                case INTEL_PT_PIP:
2014                        intel_pt_update_pip(decoder);
2015                        break;
2016
2017                case INTEL_PT_MTC:
2018                        intel_pt_calc_mtc_timestamp(decoder);
2019                        if (decoder->period_type == INTEL_PT_PERIOD_MTC)
2020                                decoder->state.type |= INTEL_PT_INSTRUCTION;
2021                        break;
2022
2023                case INTEL_PT_CYC:
2024                        intel_pt_calc_cyc_timestamp(decoder);
2025                        break;
2026
2027                case INTEL_PT_MODE_EXEC:
2028                        decoder->exec_mode = decoder->packet.payload;
2029                        break;
2030
2031                case INTEL_PT_VMCS:
2032                case INTEL_PT_MNT:
2033                case INTEL_PT_PAD:
2034                        break;
2035
2036                default:
2037                        return intel_pt_bug(decoder);
2038                }
2039        }
2040}
2041
2042static int intel_pt_resample(struct intel_pt_decoder *decoder)
2043{
2044        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2045        decoder->state.type = INTEL_PT_INSTRUCTION;
2046        decoder->state.from_ip = decoder->ip;
2047        decoder->state.to_ip = 0;
2048        return 0;
2049}
2050
2051struct intel_pt_vm_tsc_info {
2052        struct intel_pt_pkt pip_packet;
2053        struct intel_pt_pkt vmcs_packet;
2054        struct intel_pt_pkt tma_packet;
2055        bool tsc, pip, vmcs, tma, psbend;
2056        uint64_t ctc_delta;
2057        uint64_t last_ctc;
2058        int max_lookahead;
2059};
2060
2061/* Lookahead and get the PIP, VMCS and TMA packets from PSB+ */
2062static int intel_pt_vm_psb_lookahead_cb(struct intel_pt_pkt_info *pkt_info)
2063{
2064        struct intel_pt_vm_tsc_info *data = pkt_info->data;
2065
2066        switch (pkt_info->packet.type) {
2067        case INTEL_PT_PAD:
2068        case INTEL_PT_MNT:
2069        case INTEL_PT_MODE_EXEC:
2070        case INTEL_PT_MODE_TSX:
2071        case INTEL_PT_MTC:
2072        case INTEL_PT_FUP:
2073        case INTEL_PT_CYC:
2074        case INTEL_PT_CBR:
2075                break;
2076
2077        case INTEL_PT_TSC:
2078                data->tsc = true;
2079                break;
2080
2081        case INTEL_PT_TMA:
2082                data->tma_packet = pkt_info->packet;
2083                data->tma = true;
2084                break;
2085
2086        case INTEL_PT_PIP:
2087                data->pip_packet = pkt_info->packet;
2088                data->pip = true;
2089                break;
2090
2091        case INTEL_PT_VMCS:
2092                data->vmcs_packet = pkt_info->packet;
2093                data->vmcs = true;
2094                break;
2095
2096        case INTEL_PT_PSBEND:
2097                data->psbend = true;
2098                return 1;
2099
2100        case INTEL_PT_TIP_PGE:
2101        case INTEL_PT_PTWRITE:
2102        case INTEL_PT_PTWRITE_IP:
2103        case INTEL_PT_EXSTOP:
2104        case INTEL_PT_EXSTOP_IP:
2105        case INTEL_PT_MWAIT:
2106        case INTEL_PT_PWRE:
2107        case INTEL_PT_PWRX:
2108        case INTEL_PT_BBP:
2109        case INTEL_PT_BIP:
2110        case INTEL_PT_BEP:
2111        case INTEL_PT_BEP_IP:
2112        case INTEL_PT_OVF:
2113        case INTEL_PT_BAD:
2114        case INTEL_PT_TNT:
2115        case INTEL_PT_TIP_PGD:
2116        case INTEL_PT_TIP:
2117        case INTEL_PT_PSB:
2118        case INTEL_PT_TRACESTOP:
2119        default:
2120                return 1;
2121        }
2122
2123        return 0;
2124}
2125
2126struct intel_pt_ovf_fup_info {
2127        int max_lookahead;
2128        bool found;
2129};
2130
2131/* Lookahead to detect a FUP packet after OVF */
2132static int intel_pt_ovf_fup_lookahead_cb(struct intel_pt_pkt_info *pkt_info)
2133{
2134        struct intel_pt_ovf_fup_info *data = pkt_info->data;
2135
2136        if (pkt_info->packet.type == INTEL_PT_CYC ||
2137            pkt_info->packet.type == INTEL_PT_MTC ||
2138            pkt_info->packet.type == INTEL_PT_TSC)
2139                return !--(data->max_lookahead);
2140        data->found = pkt_info->packet.type == INTEL_PT_FUP;
2141        return 1;
2142}
2143
2144static bool intel_pt_ovf_fup_lookahead(struct intel_pt_decoder *decoder)
2145{
2146        struct intel_pt_ovf_fup_info data = {
2147                .max_lookahead = 16,
2148                .found = false,
2149        };
2150
2151        intel_pt_pkt_lookahead(decoder, intel_pt_ovf_fup_lookahead_cb, &data);
2152        return data.found;
2153}
2154
2155/* Lookahead and get the TMA packet after TSC */
2156static int intel_pt_tma_lookahead_cb(struct intel_pt_pkt_info *pkt_info)
2157{
2158        struct intel_pt_vm_tsc_info *data = pkt_info->data;
2159
2160        if (pkt_info->packet.type == INTEL_PT_CYC ||
2161            pkt_info->packet.type == INTEL_PT_MTC)
2162                return !--(data->max_lookahead);
2163
2164        if (pkt_info->packet.type == INTEL_PT_TMA) {
2165                data->tma_packet = pkt_info->packet;
2166                data->tma = true;
2167        }
2168        return 1;
2169}
2170
2171static uint64_t intel_pt_ctc_to_tsc(struct intel_pt_decoder *decoder, uint64_t ctc)
2172{
2173        if (decoder->tsc_ctc_mult)
2174                return ctc * decoder->tsc_ctc_mult;
2175        else
2176                return multdiv(ctc, decoder->tsc_ctc_ratio_n, decoder->tsc_ctc_ratio_d);
2177}
2178
2179static uint64_t intel_pt_calc_expected_tsc(struct intel_pt_decoder *decoder,
2180                                           uint32_t ctc,
2181                                           uint32_t fc,
2182                                           uint64_t last_ctc_timestamp,
2183                                           uint64_t ctc_delta,
2184                                           uint32_t last_ctc)
2185{
2186        /* Number of CTC ticks from last_ctc_timestamp to last_mtc */
2187        uint64_t last_mtc_ctc = last_ctc + ctc_delta;
2188        /*
2189         * Number of CTC ticks from there until current TMA packet. We would
2190         * expect last_mtc_ctc to be before ctc, but the TSC packet can slip
2191         * past an MTC, so a sign-extended value is used.
2192         */
2193        uint64_t delta = (int16_t)((uint16_t)ctc - (uint16_t)last_mtc_ctc);
2194        /* Total CTC ticks from last_ctc_timestamp to current TMA packet */
2195        uint64_t new_ctc_delta = ctc_delta + delta;
2196        uint64_t expected_tsc;
2197
2198        /*
2199         * Convert CTC ticks to TSC ticks, add the starting point
2200         * (last_ctc_timestamp) and the fast counter from the TMA packet.
2201         */
2202        expected_tsc = last_ctc_timestamp + intel_pt_ctc_to_tsc(decoder, new_ctc_delta) + fc;
2203
2204        if (intel_pt_enable_logging) {
2205                intel_pt_log_x64(last_mtc_ctc);
2206                intel_pt_log_x32(last_ctc);
2207                intel_pt_log_x64(ctc_delta);
2208                intel_pt_log_x64(delta);
2209                intel_pt_log_x32(ctc);
2210                intel_pt_log_x64(new_ctc_delta);
2211                intel_pt_log_x64(last_ctc_timestamp);
2212                intel_pt_log_x32(fc);
2213                intel_pt_log_x64(intel_pt_ctc_to_tsc(decoder, new_ctc_delta));
2214                intel_pt_log_x64(expected_tsc);
2215        }
2216
2217        return expected_tsc;
2218}
2219
2220static uint64_t intel_pt_expected_tsc(struct intel_pt_decoder *decoder,
2221                                      struct intel_pt_vm_tsc_info *data)
2222{
2223        uint32_t ctc = data->tma_packet.payload;
2224        uint32_t fc = data->tma_packet.count;
2225
2226        return intel_pt_calc_expected_tsc(decoder, ctc, fc,
2227                                          decoder->ctc_timestamp,
2228                                          data->ctc_delta, data->last_ctc);
2229}
2230
2231static void intel_pt_translate_vm_tsc(struct intel_pt_decoder *decoder,
2232                                      struct intel_pt_vmcs_info *vmcs_info)
2233{
2234        uint64_t payload = decoder->packet.payload;
2235
2236        /* VMX adds the TSC Offset, so subtract to get host TSC */
2237        decoder->packet.payload -= vmcs_info->tsc_offset;
2238        /* TSC packet has only 7 bytes */
2239        decoder->packet.payload &= SEVEN_BYTES;
2240
2241        /*
2242         * The buffer is mmapped from the data file, so this also updates the
2243         * data file.
2244         */
2245        if (!decoder->vm_tm_corr_dry_run)
2246                memcpy((void *)decoder->buf + 1, &decoder->packet.payload, 7);
2247
2248        intel_pt_log("Translated VM TSC %#" PRIx64 " -> %#" PRIx64
2249                     "    VMCS %#" PRIx64 "    TSC Offset %#" PRIx64 "\n",
2250                     payload, decoder->packet.payload, vmcs_info->vmcs,
2251                     vmcs_info->tsc_offset);
2252}
2253
2254static void intel_pt_translate_vm_tsc_offset(struct intel_pt_decoder *decoder,
2255                                             uint64_t tsc_offset)
2256{
2257        struct intel_pt_vmcs_info vmcs_info = {
2258                .vmcs = NO_VMCS,
2259                .tsc_offset = tsc_offset
2260        };
2261
2262        intel_pt_translate_vm_tsc(decoder, &vmcs_info);
2263}
2264
2265static inline bool in_vm(uint64_t pip_payload)
2266{
2267        return pip_payload & 1;
2268}
2269
2270static inline bool pip_in_vm(struct intel_pt_pkt *pip_packet)
2271{
2272        return pip_packet->payload & 1;
2273}
2274
2275static void intel_pt_print_vmcs_info(struct intel_pt_vmcs_info *vmcs_info)
2276{
2277        p_log("VMCS: %#" PRIx64 "  TSC Offset %#" PRIx64,
2278              vmcs_info->vmcs, vmcs_info->tsc_offset);
2279}
2280
2281static void intel_pt_vm_tm_corr_psb(struct intel_pt_decoder *decoder,
2282                                    struct intel_pt_vm_tsc_info *data)
2283{
2284        memset(data, 0, sizeof(*data));
2285        data->ctc_delta = decoder->ctc_delta;
2286        data->last_ctc = decoder->last_ctc;
2287        intel_pt_pkt_lookahead(decoder, intel_pt_vm_psb_lookahead_cb, data);
2288        if (data->tsc && !data->psbend)
2289                p_log("ERROR: PSB without PSBEND");
2290        decoder->in_psb = data->psbend;
2291}
2292
2293static void intel_pt_vm_tm_corr_first_tsc(struct intel_pt_decoder *decoder,
2294                                          struct intel_pt_vm_tsc_info *data,
2295                                          struct intel_pt_vmcs_info *vmcs_info,
2296                                          uint64_t host_tsc)
2297{
2298        if (!decoder->in_psb) {
2299                /* Can't happen */
2300                p_log("ERROR: First TSC is not in PSB+");
2301        }
2302
2303        if (data->pip) {
2304                if (pip_in_vm(&data->pip_packet)) { /* Guest */
2305                        if (vmcs_info && vmcs_info->tsc_offset) {
2306                                intel_pt_translate_vm_tsc(decoder, vmcs_info);
2307                                decoder->vm_tm_corr_reliable = true;
2308                        } else {
2309                                p_log("ERROR: First TSC, unknown TSC Offset");
2310                        }
2311                } else { /* Host */
2312                        decoder->vm_tm_corr_reliable = true;
2313                }
2314        } else { /* Host or Guest */
2315                decoder->vm_tm_corr_reliable = false;
2316                if (intel_pt_time_in_range(decoder, host_tsc)) {
2317                        /* Assume Host */
2318                } else {
2319                        /* Assume Guest */
2320                        if (vmcs_info && vmcs_info->tsc_offset)
2321                                intel_pt_translate_vm_tsc(decoder, vmcs_info);
2322                        else
2323                                p_log("ERROR: First TSC, no PIP, unknown TSC Offset");
2324                }
2325        }
2326}
2327
2328static void intel_pt_vm_tm_corr_tsc(struct intel_pt_decoder *decoder,
2329                                    struct intel_pt_vm_tsc_info *data)
2330{
2331        struct intel_pt_vmcs_info *vmcs_info;
2332        uint64_t tsc_offset = 0;
2333        uint64_t vmcs;
2334        bool reliable = true;
2335        uint64_t expected_tsc;
2336        uint64_t host_tsc;
2337        uint64_t ref_timestamp;
2338
2339        bool assign = false;
2340        bool assign_reliable = false;
2341
2342        /* Already have 'data' for the in_psb case */
2343        if (!decoder->in_psb) {
2344                memset(data, 0, sizeof(*data));
2345                data->ctc_delta = decoder->ctc_delta;
2346                data->last_ctc = decoder->last_ctc;
2347                data->max_lookahead = 16;
2348                intel_pt_pkt_lookahead(decoder, intel_pt_tma_lookahead_cb, data);
2349                if (decoder->pge) {
2350                        data->pip = true;
2351                        data->pip_packet.payload = decoder->pip_payload;
2352                }
2353        }
2354
2355        /* Calculations depend on having TMA packets */
2356        if (!data->tma) {
2357                p_log("ERROR: TSC without TMA");
2358                return;
2359        }
2360
2361        vmcs = data->vmcs ? data->vmcs_packet.payload : decoder->vmcs;
2362        if (vmcs == NO_VMCS)
2363                vmcs = 0;
2364
2365        vmcs_info = decoder->findnew_vmcs_info(decoder->data, vmcs);
2366
2367        ref_timestamp = decoder->timestamp ? decoder->timestamp : decoder->buf_timestamp;
2368        host_tsc = intel_pt_8b_tsc(decoder->packet.payload, ref_timestamp);
2369
2370        if (!decoder->ctc_timestamp) {
2371                intel_pt_vm_tm_corr_first_tsc(decoder, data, vmcs_info, host_tsc);
2372                return;
2373        }
2374
2375        expected_tsc = intel_pt_expected_tsc(decoder, data);
2376
2377        tsc_offset = host_tsc - expected_tsc;
2378
2379        /* Determine if TSC is from Host or Guest */
2380        if (data->pip) {
2381                if (pip_in_vm(&data->pip_packet)) { /* Guest */
2382                        if (!vmcs_info) {
2383                                /* PIP NR=1 without VMCS cannot happen */
2384                                p_log("ERROR: Missing VMCS");
2385                                intel_pt_translate_vm_tsc_offset(decoder, tsc_offset);
2386                                decoder->vm_tm_corr_reliable = false;
2387                                return;
2388                        }
2389                } else { /* Host */
2390                        decoder->last_reliable_timestamp = host_tsc;
2391                        decoder->vm_tm_corr_reliable = true;
2392                        return;
2393                }
2394        } else { /* Host or Guest */
2395                reliable = false; /* Host/Guest is a guess, so not reliable */
2396                if (decoder->in_psb) {
2397                        if (!tsc_offset)
2398                                return; /* Zero TSC Offset, assume Host */
2399                        /*
2400                         * TSC packet has only 7 bytes of TSC. We have no
2401                         * information about the Guest's 8th byte, but it
2402                         * doesn't matter because we only need 7 bytes.
2403                         * Here, since the 8th byte is unreliable and
2404                         * irrelevant, compare only 7 byes.
2405                         */
2406                        if (vmcs_info &&
2407                            (tsc_offset & SEVEN_BYTES) ==
2408                            (vmcs_info->tsc_offset & SEVEN_BYTES)) {
2409                                /* Same TSC Offset as last VMCS, assume Guest */
2410                                goto guest;
2411                        }
2412                }
2413                /*
2414                 * Check if the host_tsc is within the expected range.
2415                 * Note, we could narrow the range more by looking ahead for
2416                 * the next host TSC in the same buffer, but we don't bother to
2417                 * do that because this is probably good enough.
2418                 */
2419                if (host_tsc >= expected_tsc && intel_pt_time_in_range(decoder, host_tsc)) {
2420                        /* Within expected range for Host TSC, assume Host */
2421                        decoder->vm_tm_corr_reliable = false;
2422                        return;
2423                }
2424        }
2425
2426guest: /* Assuming Guest */
2427
2428        /* Determine whether to assign TSC Offset */
2429        if (vmcs_info && vmcs_info->vmcs) {
2430                if (vmcs_info->tsc_offset && vmcs_info->reliable) {
2431                        assign = false;
2432                } else if (decoder->in_psb && data->pip && decoder->vm_tm_corr_reliable &&
2433                           decoder->vm_tm_corr_continuous && decoder->vm_tm_corr_same_buf) {
2434                        /* Continuous tracing, TSC in a PSB is not a time loss */
2435                        assign = true;
2436                        assign_reliable = true;
2437                } else if (decoder->in_psb && data->pip && decoder->vm_tm_corr_same_buf) {
2438                        /*
2439                         * Unlikely to be a time loss TSC in a PSB which is not
2440                         * at the start of a buffer.
2441                         */
2442                        assign = true;
2443                        assign_reliable = false;
2444                }
2445        }
2446
2447        /* Record VMCS TSC Offset */
2448        if (assign && (vmcs_info->tsc_offset != tsc_offset ||
2449                       vmcs_info->reliable != assign_reliable)) {
2450                bool print = vmcs_info->tsc_offset != tsc_offset;
2451
2452                vmcs_info->tsc_offset = tsc_offset;
2453                vmcs_info->reliable = assign_reliable;
2454                if (print)
2455                        intel_pt_print_vmcs_info(vmcs_info);
2456        }
2457
2458        /* Determine what TSC Offset to use */
2459        if (vmcs_info && vmcs_info->tsc_offset) {
2460                if (!vmcs_info->reliable)
2461                        reliable = false;
2462                intel_pt_translate_vm_tsc(decoder, vmcs_info);
2463        } else {
2464                reliable = false;
2465                if (vmcs_info) {
2466                        if (!vmcs_info->error_printed) {
2467                                p_log("ERROR: Unknown TSC Offset for VMCS %#" PRIx64,
2468                                      vmcs_info->vmcs);
2469                                vmcs_info->error_printed = true;
2470                        }
2471                } else {
2472                        if (intel_pt_print_once(decoder, INTEL_PT_PRT_ONCE_UNK_VMCS))
2473                                p_log("ERROR: Unknown VMCS");
2474                }
2475                intel_pt_translate_vm_tsc_offset(decoder, tsc_offset);
2476        }
2477
2478        decoder->vm_tm_corr_reliable = reliable;
2479}
2480
2481static void intel_pt_vm_tm_corr_pebs_tsc(struct intel_pt_decoder *decoder)
2482{
2483        uint64_t host_tsc = decoder->packet.payload;
2484        uint64_t guest_tsc = decoder->packet.payload;
2485        struct intel_pt_vmcs_info *vmcs_info;
2486        uint64_t vmcs;
2487
2488        vmcs = decoder->vmcs;
2489        if (vmcs == NO_VMCS)
2490                vmcs = 0;
2491
2492        vmcs_info = decoder->findnew_vmcs_info(decoder->data, vmcs);
2493
2494        if (decoder->pge) {
2495                if (in_vm(decoder->pip_payload)) { /* Guest */
2496                        if (!vmcs_info) {
2497                                /* PIP NR=1 without VMCS cannot happen */
2498                                p_log("ERROR: Missing VMCS");
2499                        }
2500                } else { /* Host */
2501                        return;
2502                }
2503        } else { /* Host or Guest */
2504                if (intel_pt_time_in_range(decoder, host_tsc)) {
2505                        /* Within expected range for Host TSC, assume Host */
2506                        return;
2507                }
2508        }
2509
2510        if (vmcs_info) {
2511                /* Translate Guest TSC to Host TSC */
2512                host_tsc = ((guest_tsc & SEVEN_BYTES) - vmcs_info->tsc_offset) & SEVEN_BYTES;
2513                host_tsc = intel_pt_8b_tsc(host_tsc, decoder->timestamp);
2514                intel_pt_log("Translated VM TSC %#" PRIx64 " -> %#" PRIx64
2515                             "    VMCS %#" PRIx64 "    TSC Offset %#" PRIx64 "\n",
2516                             guest_tsc, host_tsc, vmcs_info->vmcs,
2517                             vmcs_info->tsc_offset);
2518                if (!intel_pt_time_in_range(decoder, host_tsc) &&
2519                    intel_pt_print_once(decoder, INTEL_PT_PRT_ONCE_ERANGE))
2520                        p_log("Timestamp out of range");
2521        } else {
2522                if (intel_pt_print_once(decoder, INTEL_PT_PRT_ONCE_UNK_VMCS))
2523                        p_log("ERROR: Unknown VMCS");
2524                host_tsc = decoder->timestamp;
2525        }
2526
2527        decoder->packet.payload = host_tsc;
2528
2529        if (!decoder->vm_tm_corr_dry_run)
2530                memcpy((void *)decoder->buf + 1, &host_tsc, 8);
2531}
2532
2533static int intel_pt_vm_time_correlation(struct intel_pt_decoder *decoder)
2534{
2535        struct intel_pt_vm_tsc_info data = { .psbend = false };
2536        bool pge;
2537        int err;
2538
2539        if (decoder->in_psb)
2540                intel_pt_vm_tm_corr_psb(decoder, &data);
2541
2542        while (1) {
2543                err = intel_pt_get_next_packet(decoder);
2544                if (err == -ENOLINK)
2545                        continue;
2546                if (err)
2547                        break;
2548
2549                switch (decoder->packet.type) {
2550                case INTEL_PT_TIP_PGD:
2551                        decoder->pge = false;
2552                        decoder->vm_tm_corr_continuous = false;
2553                        break;
2554
2555                case INTEL_PT_TNT:
2556                case INTEL_PT_TIP:
2557                case INTEL_PT_TIP_PGE:
2558                        decoder->pge = true;
2559                        break;
2560
2561                case INTEL_PT_OVF:
2562                        decoder->in_psb = false;
2563                        pge = decoder->pge;
2564                        decoder->pge = intel_pt_ovf_fup_lookahead(decoder);
2565                        if (pge != decoder->pge)
2566                                intel_pt_log("Surprising PGE change in OVF!");
2567                        if (!decoder->pge)
2568                                decoder->vm_tm_corr_continuous = false;
2569                        break;
2570
2571                case INTEL_PT_FUP:
2572                        if (decoder->in_psb)
2573                                decoder->pge = true;
2574                        break;
2575
2576                case INTEL_PT_TRACESTOP:
2577                        decoder->pge = false;
2578                        decoder->vm_tm_corr_continuous = false;
2579                        decoder->have_tma = false;
2580                        break;
2581
2582                case INTEL_PT_PSB:
2583                        intel_pt_vm_tm_corr_psb(decoder, &data);
2584                        break;
2585
2586                case INTEL_PT_PIP:
2587                        decoder->pip_payload = decoder->packet.payload;
2588                        break;
2589
2590                case INTEL_PT_MTC:
2591                        intel_pt_calc_mtc_timestamp(decoder);
2592                        break;
2593
2594                case INTEL_PT_TSC:
2595                        intel_pt_vm_tm_corr_tsc(decoder, &data);
2596                        intel_pt_calc_tsc_timestamp(decoder);
2597                        decoder->vm_tm_corr_same_buf = true;
2598                        decoder->vm_tm_corr_continuous = decoder->pge;
2599                        break;
2600
2601                case INTEL_PT_TMA:
2602                        intel_pt_calc_tma(decoder);
2603                        break;
2604
2605                case INTEL_PT_CYC:
2606                        intel_pt_calc_cyc_timestamp(decoder);
2607                        break;
2608
2609                case INTEL_PT_CBR:
2610                        intel_pt_calc_cbr(decoder);
2611                        break;
2612
2613                case INTEL_PT_PSBEND:
2614                        decoder->in_psb = false;
2615                        data.psbend = false;
2616                        break;
2617
2618                case INTEL_PT_VMCS:
2619                        if (decoder->packet.payload != NO_VMCS)
2620                                decoder->vmcs = decoder->packet.payload;
2621                        break;
2622
2623                case INTEL_PT_BBP:
2624                        decoder->blk_type = decoder->packet.payload;
2625                        break;
2626
2627                case INTEL_PT_BIP:
2628                        if (decoder->blk_type == INTEL_PT_PEBS_BASIC &&
2629                            decoder->packet.count == 2)
2630                                intel_pt_vm_tm_corr_pebs_tsc(decoder);
2631                        break;
2632
2633                case INTEL_PT_BEP:
2634                case INTEL_PT_BEP_IP:
2635                        decoder->blk_type = 0;
2636                        break;
2637
2638                case INTEL_PT_MODE_EXEC:
2639                case INTEL_PT_MODE_TSX:
2640                case INTEL_PT_MNT:
2641                case INTEL_PT_PAD:
2642                case INTEL_PT_PTWRITE_IP:
2643                case INTEL_PT_PTWRITE:
2644                case INTEL_PT_MWAIT:
2645                case INTEL_PT_PWRE:
2646                case INTEL_PT_EXSTOP_IP:
2647                case INTEL_PT_EXSTOP:
2648                case INTEL_PT_PWRX:
2649                case INTEL_PT_BAD: /* Does not happen */
2650                default:
2651                        break;
2652                }
2653        }
2654
2655        return err;
2656}
2657
2658#define HOP_PROCESS     0
2659#define HOP_IGNORE      1
2660#define HOP_RETURN      2
2661#define HOP_AGAIN       3
2662
2663static int intel_pt_scan_for_psb(struct intel_pt_decoder *decoder);
2664
2665/* Hop mode: Ignore TNT, do not walk code, but get ip from FUPs and TIPs */
2666static int intel_pt_hop_trace(struct intel_pt_decoder *decoder, bool *no_tip, int *err)
2667{
2668        /* Leap from PSB to PSB, getting ip from FUP within PSB+ */
2669        if (decoder->leap && !decoder->in_psb && decoder->packet.type != INTEL_PT_PSB) {
2670                *err = intel_pt_scan_for_psb(decoder);
2671                if (*err)
2672                        return HOP_RETURN;
2673        }
2674
2675        switch (decoder->packet.type) {
2676        case INTEL_PT_TNT:
2677                return HOP_IGNORE;
2678
2679        case INTEL_PT_TIP_PGD:
2680                if (!decoder->packet.count) {
2681                        intel_pt_set_nr(decoder);
2682                        return HOP_IGNORE;
2683                }
2684                intel_pt_set_ip(decoder);
2685                decoder->state.type |= INTEL_PT_TRACE_END;
2686                decoder->state.from_ip = 0;
2687                decoder->state.to_ip = decoder->ip;
2688                intel_pt_update_nr(decoder);
2689                return HOP_RETURN;
2690
2691        case INTEL_PT_TIP:
2692                if (!decoder->packet.count) {
2693                        intel_pt_set_nr(decoder);
2694                        return HOP_IGNORE;
2695                }
2696                intel_pt_set_ip(decoder);
2697                decoder->state.type = INTEL_PT_INSTRUCTION;
2698                decoder->state.from_ip = decoder->ip;
2699                decoder->state.to_ip = 0;
2700                intel_pt_update_nr(decoder);
2701                return HOP_RETURN;
2702
2703        case INTEL_PT_FUP:
2704                if (!decoder->packet.count)
2705                        return HOP_IGNORE;
2706                intel_pt_set_ip(decoder);
2707                if (intel_pt_fup_event(decoder))
2708                        return HOP_RETURN;
2709                if (!decoder->branch_enable)
2710                        *no_tip = true;
2711                if (*no_tip) {
2712                        decoder->state.type = INTEL_PT_INSTRUCTION;
2713                        decoder->state.from_ip = decoder->ip;
2714                        decoder->state.to_ip = 0;
2715                        return HOP_RETURN;
2716                }
2717                *err = intel_pt_walk_fup_tip(decoder);
2718                if (!*err)
2719                        decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
2720                return HOP_RETURN;
2721
2722        case INTEL_PT_PSB:
2723                decoder->state.psb_offset = decoder->pos;
2724                decoder->psb_ip = 0;
2725                decoder->last_ip = 0;
2726                decoder->have_last_ip = true;
2727                *err = intel_pt_walk_psbend(decoder);
2728                if (*err == -EAGAIN)
2729                        return HOP_AGAIN;
2730                if (*err)
2731                        return HOP_RETURN;
2732                decoder->state.type = INTEL_PT_PSB_EVT;
2733                if (decoder->psb_ip) {
2734                        decoder->state.type |= INTEL_PT_INSTRUCTION;
2735                        decoder->ip = decoder->psb_ip;
2736                }
2737                decoder->state.from_ip = decoder->psb_ip;
2738                decoder->state.to_ip = 0;
2739                return HOP_RETURN;
2740
2741        case INTEL_PT_BAD:
2742        case INTEL_PT_PAD:
2743        case INTEL_PT_TIP_PGE:
2744        case INTEL_PT_TSC:
2745        case INTEL_PT_TMA:
2746        case INTEL_PT_MODE_EXEC:
2747        case INTEL_PT_MODE_TSX:
2748        case INTEL_PT_MTC:
2749        case INTEL_PT_CYC:
2750        case INTEL_PT_VMCS:
2751        case INTEL_PT_PSBEND:
2752        case INTEL_PT_CBR:
2753        case INTEL_PT_TRACESTOP:
2754        case INTEL_PT_PIP:
2755        case INTEL_PT_OVF:
2756        case INTEL_PT_MNT:
2757        case INTEL_PT_PTWRITE:
2758        case INTEL_PT_PTWRITE_IP:
2759        case INTEL_PT_EXSTOP:
2760        case INTEL_PT_EXSTOP_IP:
2761        case INTEL_PT_MWAIT:
2762        case INTEL_PT_PWRE:
2763        case INTEL_PT_PWRX:
2764        case INTEL_PT_BBP:
2765        case INTEL_PT_BIP:
2766        case INTEL_PT_BEP:
2767        case INTEL_PT_BEP_IP:
2768        default:
2769                return HOP_PROCESS;
2770        }
2771}
2772
2773struct intel_pt_psb_info {
2774        struct intel_pt_pkt fup_packet;
2775        bool fup;
2776        int after_psbend;
2777};
2778
2779/* Lookahead and get the FUP packet from PSB+ */
2780static int intel_pt_psb_lookahead_cb(struct intel_pt_pkt_info *pkt_info)
2781{
2782        struct intel_pt_psb_info *data = pkt_info->data;
2783
2784        switch (pkt_info->packet.type) {
2785        case INTEL_PT_PAD:
2786        case INTEL_PT_MNT:
2787        case INTEL_PT_TSC:
2788        case INTEL_PT_TMA:
2789        case INTEL_PT_MODE_EXEC:
2790        case INTEL_PT_MODE_TSX:
2791        case INTEL_PT_MTC:
2792        case INTEL_PT_CYC:
2793        case INTEL_PT_VMCS:
2794        case INTEL_PT_CBR:
2795        case INTEL_PT_PIP:
2796                if (data->after_psbend) {
2797                        data->after_psbend -= 1;
2798                        if (!data->after_psbend)
2799                                return 1;
2800                }
2801                break;
2802
2803        case INTEL_PT_FUP:
2804                if (data->after_psbend)
2805                        return 1;
2806                if (data->fup || pkt_info->packet.count == 0)
2807                        return 1;
2808                data->fup_packet = pkt_info->packet;
2809                data->fup = true;
2810                break;
2811
2812        case INTEL_PT_PSBEND:
2813                if (!data->fup)
2814                        return 1;
2815                /* Keep going to check for a TIP.PGE */
2816                data->after_psbend = 6;
2817                break;
2818
2819        case INTEL_PT_TIP_PGE:
2820                /* Ignore FUP in PSB+ if followed by TIP.PGE */
2821                if (data->after_psbend)
2822                        data->fup = false;
2823                return 1;
2824
2825        case INTEL_PT_PTWRITE:
2826        case INTEL_PT_PTWRITE_IP:
2827        case INTEL_PT_EXSTOP:
2828        case INTEL_PT_EXSTOP_IP:
2829        case INTEL_PT_MWAIT:
2830        case INTEL_PT_PWRE:
2831        case INTEL_PT_PWRX:
2832        case INTEL_PT_BBP:
2833        case INTEL_PT_BIP:
2834        case INTEL_PT_BEP:
2835        case INTEL_PT_BEP_IP:
2836                if (data->after_psbend) {
2837                        data->after_psbend -= 1;
2838                        if (!data->after_psbend)
2839                                return 1;
2840                        break;
2841                }
2842                return 1;
2843
2844        case INTEL_PT_OVF:
2845        case INTEL_PT_BAD:
2846        case INTEL_PT_TNT:
2847        case INTEL_PT_TIP_PGD:
2848        case INTEL_PT_TIP:
2849        case INTEL_PT_PSB:
2850        case INTEL_PT_TRACESTOP:
2851        default:
2852                return 1;
2853        }
2854
2855        return 0;
2856}
2857
2858static int intel_pt_psb(struct intel_pt_decoder *decoder)
2859{
2860        int err;
2861
2862        decoder->last_ip = 0;
2863        decoder->psb_ip = 0;
2864        decoder->have_last_ip = true;
2865        intel_pt_clear_stack(&decoder->stack);
2866        err = intel_pt_walk_psbend(decoder);
2867        if (err)
2868                return err;
2869        decoder->state.type = INTEL_PT_PSB_EVT;
2870        decoder->state.from_ip = decoder->psb_ip;
2871        decoder->state.to_ip = 0;
2872        return 0;
2873}
2874
2875static int intel_pt_fup_in_psb(struct intel_pt_decoder *decoder)
2876{
2877        int err;
2878
2879        if (decoder->ip != decoder->last_ip) {
2880                err = intel_pt_walk_fup(decoder);
2881                if (!err || err != -EAGAIN)
2882                        return err;
2883        }
2884
2885        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2886        err = intel_pt_psb(decoder);
2887        if (err) {
2888                decoder->pkt_state = INTEL_PT_STATE_ERR3;
2889                return -ENOENT;
2890        }
2891
2892        return 0;
2893}
2894
2895static bool intel_pt_psb_with_fup(struct intel_pt_decoder *decoder, int *err)
2896{
2897        struct intel_pt_psb_info data = { .fup = false };
2898
2899        if (!decoder->branch_enable || !decoder->pge)
2900                return false;
2901
2902        intel_pt_pkt_lookahead(decoder, intel_pt_psb_lookahead_cb, &data);
2903        if (!data.fup)
2904                return false;
2905
2906        decoder->packet = data.fup_packet;
2907        intel_pt_set_last_ip(decoder);
2908        decoder->pkt_state = INTEL_PT_STATE_FUP_IN_PSB;
2909
2910        *err = intel_pt_fup_in_psb(decoder);
2911
2912        return true;
2913}
2914
2915static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
2916{
2917        int last_packet_type = INTEL_PT_PAD;
2918        bool no_tip = false;
2919        int err;
2920
2921        while (1) {
2922                err = intel_pt_get_next_packet(decoder);
2923                if (err)
2924                        return err;
2925next:
2926                if (decoder->cyc_threshold) {
2927                        if (decoder->sample_cyc && last_packet_type != INTEL_PT_CYC)
2928                                decoder->sample_cyc = false;
2929                        last_packet_type = decoder->packet.type;
2930                }
2931
2932                if (decoder->hop) {
2933                        switch (intel_pt_hop_trace(decoder, &no_tip, &err)) {
2934                        case HOP_IGNORE:
2935                                continue;
2936                        case HOP_RETURN:
2937                                return err;
2938                        case HOP_AGAIN:
2939                                goto next;
2940                        default:
2941                                break;
2942                        }
2943                }
2944
2945                switch (decoder->packet.type) {
2946                case INTEL_PT_TNT:
2947                        if (!decoder->packet.count)
2948                                break;
2949                        decoder->tnt = decoder->packet;
2950                        decoder->pkt_state = INTEL_PT_STATE_TNT;
2951                        err = intel_pt_walk_tnt(decoder);
2952                        if (err == -EAGAIN)
2953                                break;
2954                        return err;
2955
2956                case INTEL_PT_TIP_PGD:
2957                        if (decoder->packet.count != 0)
2958                                intel_pt_set_last_ip(decoder);
2959                        decoder->pkt_state = INTEL_PT_STATE_TIP_PGD;
2960                        return intel_pt_walk_tip(decoder);
2961
2962                case INTEL_PT_TIP_PGE: {
2963                        decoder->pge = true;
2964                        intel_pt_mtc_cyc_cnt_pge(decoder);
2965                        intel_pt_set_nr(decoder);
2966                        if (decoder->packet.count == 0) {
2967                                intel_pt_log_at("Skipping zero TIP.PGE",
2968                                                decoder->pos);
2969                                break;
2970                        }
2971                        intel_pt_set_ip(decoder);
2972                        decoder->state.from_ip = 0;
2973                        decoder->state.to_ip = decoder->ip;
2974                        decoder->state.type |= INTEL_PT_TRACE_BEGIN;
2975                        /*
2976                         * In hop mode, resample to get the to_ip as an
2977                         * "instruction" sample.
2978                         */
2979                        if (decoder->hop)
2980                                decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
2981                        return 0;
2982                }
2983
2984                case INTEL_PT_OVF:
2985                        return intel_pt_overflow(decoder);
2986
2987                case INTEL_PT_TIP:
2988                        if (decoder->packet.count != 0)
2989                                intel_pt_set_last_ip(decoder);
2990                        decoder->pkt_state = INTEL_PT_STATE_TIP;
2991                        return intel_pt_walk_tip(decoder);
2992
2993                case INTEL_PT_FUP:
2994                        if (decoder->packet.count == 0) {
2995                                intel_pt_log_at("Skipping zero FUP",
2996                                                decoder->pos);
2997                                no_tip = false;
2998                                break;
2999                        }
3000                        intel_pt_set_last_ip(decoder);
3001                        if (!decoder->branch_enable) {
3002                                decoder->ip = decoder->last_ip;
3003                                if (intel_pt_fup_event(decoder))
3004                                        return 0;
3005                                no_tip = false;
3006                                break;
3007                        }
3008                        if (decoder->set_fup_mwait)
3009                                no_tip = true;
3010                        if (no_tip)
3011                                decoder->pkt_state = INTEL_PT_STATE_FUP_NO_TIP;
3012                        else
3013                                decoder->pkt_state = INTEL_PT_STATE_FUP;
3014                        err = intel_pt_walk_fup(decoder);
3015                        if (err != -EAGAIN)
3016                                return err;
3017                        if (no_tip) {
3018                                no_tip = false;
3019                                break;
3020                        }
3021                        return intel_pt_walk_fup_tip(decoder);
3022
3023                case INTEL_PT_TRACESTOP:
3024                        decoder->pge = false;
3025                        decoder->continuous_period = false;
3026                        intel_pt_clear_tx_flags(decoder);
3027                        decoder->have_tma = false;
3028                        break;
3029
3030                case INTEL_PT_PSB:
3031                        decoder->state.psb_offset = decoder->pos;
3032                        decoder->psb_ip = 0;
3033                        if (intel_pt_psb_with_fup(decoder, &err))
3034                                return err;
3035                        err = intel_pt_psb(decoder);
3036                        if (err == -EAGAIN)
3037                                goto next;
3038                        return err;
3039
3040                case INTEL_PT_PIP:
3041                        intel_pt_update_pip(decoder);
3042                        break;
3043
3044                case INTEL_PT_MTC:
3045                        intel_pt_calc_mtc_timestamp(decoder);
3046                        if (decoder->period_type != INTEL_PT_PERIOD_MTC)
3047                                break;
3048                        /*
3049                         * Ensure that there has been an instruction since the
3050                         * last MTC.
3051                         */
3052                        if (!decoder->mtc_insn)
3053                                break;
3054                        decoder->mtc_insn = false;
3055                        /* Ensure that there is a timestamp */
3056                        if (!decoder->timestamp)
3057                                break;
3058                        decoder->state.type = INTEL_PT_INSTRUCTION;
3059                        decoder->state.from_ip = decoder->ip;
3060                        decoder->state.to_ip = 0;
3061                        decoder->mtc_insn = false;
3062                        return 0;
3063
3064                case INTEL_PT_TSC:
3065                        intel_pt_calc_tsc_timestamp(decoder);
3066                        break;
3067
3068                case INTEL_PT_TMA:
3069                        intel_pt_calc_tma(decoder);
3070                        break;
3071
3072                case INTEL_PT_CYC:
3073                        intel_pt_calc_cyc_timestamp(decoder);
3074                        break;
3075
3076                case INTEL_PT_CBR:
3077                        intel_pt_calc_cbr(decoder);
3078                        if (decoder->cbr != decoder->cbr_seen) {
3079                                decoder->state.type = 0;
3080                                return 0;
3081                        }
3082                        break;
3083
3084                case INTEL_PT_MODE_EXEC:
3085                        decoder->exec_mode = decoder->packet.payload;
3086                        break;
3087
3088                case INTEL_PT_MODE_TSX:
3089                        /* MODE_TSX need not be followed by FUP */
3090                        if (!decoder->pge || decoder->in_psb) {
3091                                intel_pt_update_in_tx(decoder);
3092                                break;
3093                        }
3094                        err = intel_pt_mode_tsx(decoder, &no_tip);
3095                        if (err)
3096                                return err;
3097                        goto next;
3098
3099                case INTEL_PT_BAD: /* Does not happen */
3100                        return intel_pt_bug(decoder);
3101
3102                case INTEL_PT_PSBEND:
3103                case INTEL_PT_VMCS:
3104                case INTEL_PT_MNT:
3105                case INTEL_PT_PAD:
3106                        break;
3107
3108                case INTEL_PT_PTWRITE_IP:
3109                        decoder->fup_ptw_payload = decoder->packet.payload;
3110                        err = intel_pt_get_next_packet(decoder);
3111                        if (err)
3112                                return err;
3113                        if (decoder->packet.type == INTEL_PT_FUP) {
3114                                decoder->set_fup_ptw = true;
3115                                no_tip = true;
3116                        } else {
3117                                intel_pt_log_at("ERROR: Missing FUP after PTWRITE",
3118                                                decoder->pos);
3119                        }
3120                        goto next;
3121
3122                case INTEL_PT_PTWRITE:
3123                        decoder->state.type = INTEL_PT_PTW;
3124                        decoder->state.from_ip = decoder->ip;
3125                        decoder->state.to_ip = 0;
3126                        decoder->state.ptw_payload = decoder->packet.payload;
3127                        return 0;
3128
3129                case INTEL_PT_MWAIT:
3130                        decoder->fup_mwait_payload = decoder->packet.payload;
3131                        decoder->set_fup_mwait = true;
3132                        break;
3133
3134                case INTEL_PT_PWRE:
3135                        if (decoder->set_fup_mwait) {
3136                                decoder->fup_pwre_payload =
3137                                                        decoder->packet.payload;
3138                                decoder->set_fup_pwre = true;
3139                                break;
3140                        }
3141                        decoder->state.type = INTEL_PT_PWR_ENTRY;
3142                        decoder->state.from_ip = decoder->ip;
3143                        decoder->state.to_ip = 0;
3144                        decoder->state.pwrx_payload = decoder->packet.payload;
3145                        return 0;
3146
3147                case INTEL_PT_EXSTOP_IP:
3148                        err = intel_pt_get_next_packet(decoder);
3149                        if (err)
3150                                return err;
3151                        if (decoder->packet.type == INTEL_PT_FUP) {
3152                                decoder->set_fup_exstop = true;
3153                                no_tip = true;
3154                        } else {
3155                                intel_pt_log_at("ERROR: Missing FUP after EXSTOP",
3156                                                decoder->pos);
3157                        }
3158                        goto next;
3159
3160                case INTEL_PT_EXSTOP:
3161                        decoder->state.type = INTEL_PT_EX_STOP;
3162                        decoder->state.from_ip = decoder->ip;
3163                        decoder->state.to_ip = 0;
3164                        return 0;
3165
3166                case INTEL_PT_PWRX:
3167                        decoder->state.type = INTEL_PT_PWR_EXIT;
3168                        decoder->state.from_ip = decoder->ip;
3169                        decoder->state.to_ip = 0;
3170                        decoder->state.pwrx_payload = decoder->packet.payload;
3171                        return 0;
3172
3173                case INTEL_PT_BBP:
3174                        intel_pt_bbp(decoder);
3175                        break;
3176
3177                case INTEL_PT_BIP:
3178                        intel_pt_bip(decoder);
3179                        break;
3180
3181                case INTEL_PT_BEP:
3182                        decoder->state.type = INTEL_PT_BLK_ITEMS;
3183                        decoder->state.from_ip = decoder->ip;
3184                        decoder->state.to_ip = 0;
3185                        return 0;
3186
3187                case INTEL_PT_BEP_IP:
3188                        err = intel_pt_get_next_packet(decoder);
3189                        if (err)
3190                                return err;
3191                        if (decoder->packet.type == INTEL_PT_FUP) {
3192                                decoder->set_fup_bep = true;
3193                                no_tip = true;
3194                        } else {
3195                                intel_pt_log_at("ERROR: Missing FUP after BEP",
3196                                                decoder->pos);
3197                        }
3198                        goto next;
3199
3200                default:
3201                        return intel_pt_bug(decoder);
3202                }
3203        }
3204}
3205
3206static inline bool intel_pt_have_ip(struct intel_pt_decoder *decoder)
3207{
3208        return decoder->packet.count &&
3209               (decoder->have_last_ip || decoder->packet.count == 3 ||
3210                decoder->packet.count == 6);
3211}
3212
3213/* Walk PSB+ packets to get in sync. */
3214static int intel_pt_walk_psb(struct intel_pt_decoder *decoder)
3215{
3216        int err;
3217
3218        decoder->in_psb = true;
3219
3220        while (1) {
3221                err = intel_pt_get_next_packet(decoder);
3222                if (err)
3223                        goto out;
3224
3225                switch (decoder->packet.type) {
3226                case INTEL_PT_TIP_PGD:
3227                        decoder->continuous_period = false;
3228                        __fallthrough;
3229                case INTEL_PT_TIP_PGE:
3230                case INTEL_PT_TIP:
3231                case INTEL_PT_PTWRITE:
3232                case INTEL_PT_PTWRITE_IP:
3233                case INTEL_PT_EXSTOP:
3234                case INTEL_PT_EXSTOP_IP:
3235                case INTEL_PT_MWAIT:
3236                case INTEL_PT_PWRE:
3237                case INTEL_PT_PWRX:
3238                case INTEL_PT_BBP:
3239                case INTEL_PT_BIP:
3240                case INTEL_PT_BEP:
3241                case INTEL_PT_BEP_IP:
3242                        intel_pt_log("ERROR: Unexpected packet\n");
3243                        err = -ENOENT;
3244                        goto out;
3245
3246                case INTEL_PT_FUP:
3247                        decoder->pge = true;
3248                        if (intel_pt_have_ip(decoder)) {
3249                                uint64_t current_ip = decoder->ip;
3250
3251                                intel_pt_set_ip(decoder);
3252                                decoder->psb_ip = decoder->ip;
3253                                if (current_ip)
3254                                        intel_pt_log_to("Setting IP",
3255                                                        decoder->ip);
3256                        }
3257                        break;
3258
3259                case INTEL_PT_MTC:
3260                        intel_pt_calc_mtc_timestamp(decoder);
3261                        break;
3262
3263                case INTEL_PT_TSC:
3264                        intel_pt_calc_tsc_timestamp(decoder);
3265                        break;
3266
3267                case INTEL_PT_TMA:
3268                        intel_pt_calc_tma(decoder);
3269                        break;
3270
3271                case INTEL_PT_CYC:
3272                        intel_pt_calc_cyc_timestamp(decoder);
3273                        break;
3274
3275                case INTEL_PT_CBR:
3276                        intel_pt_calc_cbr(decoder);
3277                        break;
3278
3279                case INTEL_PT_PIP:
3280                        intel_pt_set_pip(decoder);
3281                        break;
3282
3283                case INTEL_PT_MODE_EXEC:
3284                        decoder->exec_mode = decoder->packet.payload;
3285                        break;
3286
3287                case INTEL_PT_MODE_TSX:
3288                        intel_pt_update_in_tx(decoder);
3289                        break;
3290
3291                case INTEL_PT_TRACESTOP:
3292                        decoder->pge = false;
3293                        decoder->continuous_period = false;
3294                        intel_pt_clear_tx_flags(decoder);
3295                        __fallthrough;
3296
3297                case INTEL_PT_TNT:
3298                        decoder->have_tma = false;
3299                        intel_pt_log("ERROR: Unexpected packet\n");
3300                        if (decoder->ip)
3301                                decoder->pkt_state = INTEL_PT_STATE_ERR4;
3302                        else
3303                                decoder->pkt_state = INTEL_PT_STATE_ERR3;
3304                        err = -ENOENT;
3305                        goto out;
3306
3307                case INTEL_PT_BAD: /* Does not happen */
3308                        err = intel_pt_bug(decoder);
3309                        goto out;
3310
3311                case INTEL_PT_OVF:
3312                        err = intel_pt_overflow(decoder);
3313                        goto out;
3314
3315                case INTEL_PT_PSBEND:
3316                        err = 0;
3317                        goto out;
3318
3319                case INTEL_PT_PSB:
3320                case INTEL_PT_VMCS:
3321                case INTEL_PT_MNT:
3322                case INTEL_PT_PAD:
3323                default:
3324                        break;
3325                }
3326        }
3327out:
3328        decoder->in_psb = false;
3329
3330        return err;
3331}
3332
3333static int intel_pt_walk_to_ip(struct intel_pt_decoder *decoder)
3334{
3335        int err;
3336
3337        while (1) {
3338                err = intel_pt_get_next_packet(decoder);
3339                if (err)
3340                        return err;
3341
3342                switch (decoder->packet.type) {
3343                case INTEL_PT_TIP_PGD:
3344                        decoder->continuous_period = false;
3345                        decoder->pge = false;
3346                        if (intel_pt_have_ip(decoder))
3347                                intel_pt_set_ip(decoder);
3348                        if (!decoder->ip)
3349                                break;
3350                        decoder->state.type |= INTEL_PT_TRACE_END;
3351                        return 0;
3352
3353                case INTEL_PT_TIP_PGE:
3354                        decoder->pge = true;
3355                        intel_pt_mtc_cyc_cnt_pge(decoder);
3356                        if (intel_pt_have_ip(decoder))
3357                                intel_pt_set_ip(decoder);
3358                        if (!decoder->ip)
3359                                break;
3360                        decoder->state.type |= INTEL_PT_TRACE_BEGIN;
3361                        return 0;
3362
3363                case INTEL_PT_TIP:
3364                        decoder->pge = true;
3365                        if (intel_pt_have_ip(decoder))
3366                                intel_pt_set_ip(decoder);
3367                        if (!decoder->ip)
3368                                break;
3369                        return 0;
3370
3371                case INTEL_PT_FUP:
3372                        if (intel_pt_have_ip(decoder))
3373                                intel_pt_set_ip(decoder);
3374                        if (decoder->ip)
3375                                return 0;
3376                        break;
3377
3378                case INTEL_PT_MTC:
3379                        intel_pt_calc_mtc_timestamp(decoder);
3380                        break;
3381
3382                case INTEL_PT_TSC:
3383                        intel_pt_calc_tsc_timestamp(decoder);
3384                        break;
3385
3386                case INTEL_PT_TMA:
3387                        intel_pt_calc_tma(decoder);
3388                        break;
3389
3390                case INTEL_PT_CYC:
3391                        intel_pt_calc_cyc_timestamp(decoder);
3392                        break;
3393
3394                case INTEL_PT_CBR:
3395                        intel_pt_calc_cbr(decoder);
3396                        break;
3397
3398                case INTEL_PT_PIP:
3399                        intel_pt_set_pip(decoder);
3400                        break;
3401
3402                case INTEL_PT_MODE_EXEC:
3403                        decoder->exec_mode = decoder->packet.payload;
3404                        break;
3405
3406                case INTEL_PT_MODE_TSX:
3407                        intel_pt_update_in_tx(decoder);
3408                        break;
3409
3410                case INTEL_PT_OVF:
3411                        return intel_pt_overflow(decoder);
3412
3413                case INTEL_PT_BAD: /* Does not happen */
3414                        return intel_pt_bug(decoder);
3415
3416                case INTEL_PT_TRACESTOP:
3417                        decoder->pge = false;
3418                        decoder->continuous_period = false;
3419                        intel_pt_clear_tx_flags(decoder);
3420                        decoder->have_tma = false;
3421                        break;
3422
3423                case INTEL_PT_PSB:
3424                        decoder->state.psb_offset = decoder->pos;
3425                        decoder->psb_ip = 0;
3426                        decoder->last_ip = 0;
3427                        decoder->have_last_ip = true;
3428                        intel_pt_clear_stack(&decoder->stack);
3429                        err = intel_pt_walk_psb(decoder);
3430                        if (err)
3431                                return err;
3432                        decoder->state.type = INTEL_PT_PSB_EVT;
3433                        decoder->state.from_ip = decoder->psb_ip;
3434                        decoder->state.to_ip = 0;
3435                        return 0;
3436
3437                case INTEL_PT_TNT:
3438                case INTEL_PT_PSBEND:
3439                case INTEL_PT_VMCS:
3440                case INTEL_PT_MNT:
3441                case INTEL_PT_PAD:
3442                case INTEL_PT_PTWRITE:
3443                case INTEL_PT_PTWRITE_IP:
3444                case INTEL_PT_EXSTOP:
3445                case INTEL_PT_EXSTOP_IP:
3446                case INTEL_PT_MWAIT:
3447                case INTEL_PT_PWRE:
3448                case INTEL_PT_PWRX:
3449                case INTEL_PT_BBP:
3450                case INTEL_PT_BIP:
3451                case INTEL_PT_BEP:
3452                case INTEL_PT_BEP_IP:
3453                default:
3454                        break;
3455                }
3456        }
3457}
3458
3459static int intel_pt_sync_ip(struct intel_pt_decoder *decoder)
3460{
3461        int err;
3462
3463        decoder->set_fup_tx_flags = false;
3464        decoder->set_fup_ptw = false;
3465        decoder->set_fup_mwait = false;
3466        decoder->set_fup_pwre = false;
3467        decoder->set_fup_exstop = false;
3468        decoder->set_fup_bep = false;
3469
3470        if (!decoder->branch_enable) {
3471                decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
3472                decoder->overflow = false;
3473                decoder->state.type = 0; /* Do not have a sample */
3474                return 0;
3475        }
3476
3477        intel_pt_log("Scanning for full IP\n");
3478        err = intel_pt_walk_to_ip(decoder);
3479        if (err || ((decoder->state.type & INTEL_PT_PSB_EVT) && !decoder->ip))
3480                return err;
3481
3482        /* In hop mode, resample to get the to_ip as an "instruction" sample */
3483        if (decoder->hop)
3484                decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
3485        else
3486                decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
3487        decoder->overflow = false;
3488
3489        decoder->state.from_ip = 0;
3490        decoder->state.to_ip = decoder->ip;
3491        intel_pt_log_to("Setting IP", decoder->ip);
3492
3493        return 0;
3494}
3495
3496static int intel_pt_part_psb(struct intel_pt_decoder *decoder)
3497{
3498        const unsigned char *end = decoder->buf + decoder->len;
3499        size_t i;
3500
3501        for (i = INTEL_PT_PSB_LEN - 1; i; i--) {
3502                if (i > decoder->len)
3503                        continue;
3504                if (!memcmp(end - i, INTEL_PT_PSB_STR, i))
3505                        return i;
3506        }
3507        return 0;
3508}
3509
3510static int intel_pt_rest_psb(struct intel_pt_decoder *decoder, int part_psb)
3511{
3512        size_t rest_psb = INTEL_PT_PSB_LEN - part_psb;
3513        const char *psb = INTEL_PT_PSB_STR;
3514
3515        if (rest_psb > decoder->len ||
3516            memcmp(decoder->buf, psb + part_psb, rest_psb))
3517                return 0;
3518
3519        return rest_psb;
3520}
3521
3522static int intel_pt_get_split_psb(struct intel_pt_decoder *decoder,
3523                                  int part_psb)
3524{
3525        int rest_psb, ret;
3526
3527        decoder->pos += decoder->len;
3528        decoder->len = 0;
3529
3530        ret = intel_pt_get_next_data(decoder, false);
3531        if (ret)
3532                return ret;
3533
3534        rest_psb = intel_pt_rest_psb(decoder, part_psb);
3535        if (!rest_psb)
3536                return 0;
3537
3538        decoder->pos -= part_psb;
3539        decoder->next_buf = decoder->buf + rest_psb;
3540        decoder->next_len = decoder->len - rest_psb;
3541        memcpy(decoder->temp_buf, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
3542        decoder->buf = decoder->temp_buf;
3543        decoder->len = INTEL_PT_PSB_LEN;
3544
3545        return 0;
3546}
3547
3548static int intel_pt_scan_for_psb(struct intel_pt_decoder *decoder)
3549{
3550        unsigned char *next;
3551        int ret;
3552
3553        intel_pt_log("Scanning for PSB\n");
3554        while (1) {
3555                if (!decoder->len) {
3556                        ret = intel_pt_get_next_data(decoder, false);
3557                        if (ret)
3558                                return ret;
3559                }
3560
3561                next = memmem(decoder->buf, decoder->len, INTEL_PT_PSB_STR,
3562                              INTEL_PT_PSB_LEN);
3563                if (!next) {
3564                        int part_psb;
3565
3566                        part_psb = intel_pt_part_psb(decoder);
3567                        if (part_psb) {
3568                                ret = intel_pt_get_split_psb(decoder, part_psb);
3569                                if (ret)
3570                                        return ret;
3571                        } else {
3572                                decoder->pos += decoder->len;
3573                                decoder->len = 0;
3574                        }
3575                        continue;
3576                }
3577
3578                decoder->pkt_step = next - decoder->buf;
3579                return intel_pt_get_next_packet(decoder);
3580        }
3581}
3582
3583static int intel_pt_sync(struct intel_pt_decoder *decoder)
3584{
3585        int err;
3586
3587        decoder->pge = false;
3588        decoder->continuous_period = false;
3589        decoder->have_last_ip = false;
3590        decoder->last_ip = 0;
3591        decoder->psb_ip = 0;
3592        decoder->ip = 0;
3593        intel_pt_clear_stack(&decoder->stack);
3594
3595        err = intel_pt_scan_for_psb(decoder);
3596        if (err)
3597                return err;
3598
3599        if (decoder->vm_time_correlation) {
3600                decoder->in_psb = true;
3601                if (!decoder->timestamp)
3602                        decoder->timestamp = 1;
3603                decoder->state.type = 0;
3604                decoder->pkt_state = INTEL_PT_STATE_VM_TIME_CORRELATION;
3605                return 0;
3606        }
3607
3608        decoder->have_last_ip = true;
3609        decoder->pkt_state = INTEL_PT_STATE_NO_IP;
3610
3611        err = intel_pt_walk_psb(decoder);
3612        if (err)
3613                return err;
3614
3615        decoder->state.type = INTEL_PT_PSB_EVT; /* Only PSB sample */
3616        decoder->state.from_ip = decoder->psb_ip;
3617        decoder->state.to_ip = 0;
3618
3619        if (decoder->ip) {
3620                /*
3621                 * In hop mode, resample to get the PSB FUP ip as an
3622                 * "instruction" sample.
3623                 */
3624                if (decoder->hop)
3625                        decoder->pkt_state = INTEL_PT_STATE_RESAMPLE;
3626                else
3627                        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
3628        }
3629
3630        return 0;
3631}
3632
3633static uint64_t intel_pt_est_timestamp(struct intel_pt_decoder *decoder)
3634{
3635        uint64_t est = decoder->sample_insn_cnt << 1;
3636
3637        if (!decoder->cbr || !decoder->max_non_turbo_ratio)
3638                goto out;
3639
3640        est *= decoder->max_non_turbo_ratio;
3641        est /= decoder->cbr;
3642out:
3643        return decoder->sample_timestamp + est;
3644}
3645
3646const struct intel_pt_state *intel_pt_decode(struct intel_pt_decoder *decoder)
3647{
3648        int err;
3649
3650        do {
3651                decoder->state.type = INTEL_PT_BRANCH;
3652                decoder->state.flags = 0;
3653
3654                switch (decoder->pkt_state) {
3655                case INTEL_PT_STATE_NO_PSB:
3656                        err = intel_pt_sync(decoder);
3657                        break;
3658                case INTEL_PT_STATE_NO_IP:
3659                        decoder->have_last_ip = false;
3660                        decoder->last_ip = 0;
3661                        decoder->ip = 0;
3662                        __fallthrough;
3663                case INTEL_PT_STATE_ERR_RESYNC:
3664                        err = intel_pt_sync_ip(decoder);
3665                        break;
3666                case INTEL_PT_STATE_IN_SYNC:
3667                        err = intel_pt_walk_trace(decoder);
3668                        break;
3669                case INTEL_PT_STATE_TNT:
3670                case INTEL_PT_STATE_TNT_CONT:
3671                        err = intel_pt_walk_tnt(decoder);
3672                        if (err == -EAGAIN)
3673                                err = intel_pt_walk_trace(decoder);
3674                        break;
3675                case INTEL_PT_STATE_TIP:
3676                case INTEL_PT_STATE_TIP_PGD:
3677                        err = intel_pt_walk_tip(decoder);
3678                        break;
3679                case INTEL_PT_STATE_FUP:
3680                        err = intel_pt_walk_fup(decoder);
3681                        if (err == -EAGAIN)
3682                                err = intel_pt_walk_fup_tip(decoder);
3683                        break;
3684                case INTEL_PT_STATE_FUP_NO_TIP:
3685                        err = intel_pt_walk_fup(decoder);
3686                        if (err == -EAGAIN)
3687                                err = intel_pt_walk_trace(decoder);
3688                        break;
3689                case INTEL_PT_STATE_FUP_IN_PSB:
3690                        err = intel_pt_fup_in_psb(decoder);
3691                        break;
3692                case INTEL_PT_STATE_RESAMPLE:
3693                        err = intel_pt_resample(decoder);
3694                        break;
3695                case INTEL_PT_STATE_VM_TIME_CORRELATION:
3696                        err = intel_pt_vm_time_correlation(decoder);
3697                        break;
3698                default:
3699                        err = intel_pt_bug(decoder);
3700                        break;
3701                }
3702        } while (err == -ENOLINK);
3703
3704        if (err) {
3705                decoder->state.err = intel_pt_ext_err(err);
3706                decoder->state.from_ip = decoder->ip;
3707                intel_pt_update_sample_time(decoder);
3708                decoder->sample_tot_cyc_cnt = decoder->tot_cyc_cnt;
3709                intel_pt_set_nr(decoder);
3710        } else {
3711                decoder->state.err = 0;
3712                if (decoder->cbr != decoder->cbr_seen) {
3713                        decoder->cbr_seen = decoder->cbr;
3714                        if (!decoder->state.type) {
3715                                decoder->state.from_ip = decoder->ip;
3716                                decoder->state.to_ip = 0;
3717                        }
3718                        decoder->state.type |= INTEL_PT_CBR_CHG;
3719                        decoder->state.cbr_payload = decoder->cbr_payload;
3720                        decoder->state.cbr = decoder->cbr;
3721                }
3722                if (intel_pt_sample_time(decoder->pkt_state)) {
3723                        intel_pt_update_sample_time(decoder);
3724                        if (decoder->sample_cyc) {
3725                                decoder->sample_tot_cyc_cnt = decoder->tot_cyc_cnt;
3726                                decoder->state.flags |= INTEL_PT_SAMPLE_IPC;
3727                                decoder->sample_cyc = false;
3728                        }
3729                }
3730                /*
3731                 * When using only TSC/MTC to compute cycles, IPC can be
3732                 * sampled as soon as the cycle count changes.
3733                 */
3734                if (!decoder->have_cyc)
3735                        decoder->state.flags |= INTEL_PT_SAMPLE_IPC;
3736        }
3737
3738         /* Let PSB event always have TSC timestamp */
3739        if ((decoder->state.type & INTEL_PT_PSB_EVT) && decoder->tsc_timestamp)
3740                decoder->sample_timestamp = decoder->tsc_timestamp;
3741
3742        decoder->state.from_nr = decoder->nr;
3743        decoder->state.to_nr = decoder->next_nr;
3744        decoder->nr = decoder->next_nr;
3745
3746        decoder->state.timestamp = decoder->sample_timestamp;
3747        decoder->state.est_timestamp = intel_pt_est_timestamp(decoder);
3748        decoder->state.tot_insn_cnt = decoder->tot_insn_cnt;
3749        decoder->state.tot_cyc_cnt = decoder->sample_tot_cyc_cnt;
3750
3751        return &decoder->state;
3752}
3753
3754/**
3755 * intel_pt_next_psb - move buffer pointer to the start of the next PSB packet.
3756 * @buf: pointer to buffer pointer
3757 * @len: size of buffer
3758 *
3759 * Updates the buffer pointer to point to the start of the next PSB packet if
3760 * there is one, otherwise the buffer pointer is unchanged.  If @buf is updated,
3761 * @len is adjusted accordingly.
3762 *
3763 * Return: %true if a PSB packet is found, %false otherwise.
3764 */
3765static bool intel_pt_next_psb(unsigned char **buf, size_t *len)
3766{
3767        unsigned char *next;
3768
3769        next = memmem(*buf, *len, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
3770        if (next) {
3771                *len -= next - *buf;
3772                *buf = next;
3773                return true;
3774        }
3775        return false;
3776}
3777
3778/**
3779 * intel_pt_step_psb - move buffer pointer to the start of the following PSB
3780 *                     packet.
3781 * @buf: pointer to buffer pointer
3782 * @len: size of buffer
3783 *
3784 * Updates the buffer pointer to point to the start of the following PSB packet
3785 * (skipping the PSB at @buf itself) if there is one, otherwise the buffer
3786 * pointer is unchanged.  If @buf is updated, @len is adjusted accordingly.
3787 *
3788 * Return: %true if a PSB packet is found, %false otherwise.
3789 */
3790static bool intel_pt_step_psb(unsigned char **buf, size_t *len)
3791{
3792        unsigned char *next;
3793
3794        if (!*len)
3795                return false;
3796
3797        next = memmem(*buf + 1, *len - 1, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
3798        if (next) {
3799                *len -= next - *buf;
3800                *buf = next;
3801                return true;
3802        }
3803        return false;
3804}
3805
3806/**
3807 * intel_pt_last_psb - find the last PSB packet in a buffer.
3808 * @buf: buffer
3809 * @len: size of buffer
3810 *
3811 * This function finds the last PSB in a buffer.
3812 *
3813 * Return: A pointer to the last PSB in @buf if found, %NULL otherwise.
3814 */
3815static unsigned char *intel_pt_last_psb(unsigned char *buf, size_t len)
3816{
3817        const char *n = INTEL_PT_PSB_STR;
3818        unsigned char *p;
3819        size_t k;
3820
3821        if (len < INTEL_PT_PSB_LEN)
3822                return NULL;
3823
3824        k = len - INTEL_PT_PSB_LEN + 1;
3825        while (1) {
3826                p = memrchr(buf, n[0], k);
3827                if (!p)
3828                        return NULL;
3829                if (!memcmp(p + 1, n + 1, INTEL_PT_PSB_LEN - 1))
3830                        return p;
3831                k = p - buf;
3832                if (!k)
3833                        return NULL;
3834        }
3835}
3836
3837/**
3838 * intel_pt_next_tsc - find and return next TSC.
3839 * @buf: buffer
3840 * @len: size of buffer
3841 * @tsc: TSC value returned
3842 * @rem: returns remaining size when TSC is found
3843 *
3844 * Find a TSC packet in @buf and return the TSC value.  This function assumes
3845 * that @buf starts at a PSB and that PSB+ will contain TSC and so stops if a
3846 * PSBEND packet is found.
3847 *
3848 * Return: %true if TSC is found, false otherwise.
3849 */
3850static bool intel_pt_next_tsc(unsigned char *buf, size_t len, uint64_t *tsc,
3851                              size_t *rem)
3852{
3853        enum intel_pt_pkt_ctx ctx = INTEL_PT_NO_CTX;
3854        struct intel_pt_pkt packet;
3855        int ret;
3856
3857        while (len) {
3858                ret = intel_pt_get_packet(buf, len, &packet, &ctx);
3859                if (ret <= 0)
3860                        return false;
3861                if (packet.type == INTEL_PT_TSC) {
3862                        *tsc = packet.payload;
3863                        *rem = len;
3864                        return true;
3865                }
3866                if (packet.type == INTEL_PT_PSBEND)
3867                        return false;
3868                buf += ret;
3869                len -= ret;
3870        }
3871        return false;
3872}
3873
3874/**
3875 * intel_pt_tsc_cmp - compare 7-byte TSCs.
3876 * @tsc1: first TSC to compare
3877 * @tsc2: second TSC to compare
3878 *
3879 * This function compares 7-byte TSC values allowing for the possibility that
3880 * TSC wrapped around.  Generally it is not possible to know if TSC has wrapped
3881 * around so for that purpose this function assumes the absolute difference is