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/zalloc.h>
  18
  19#include "../cache.h"
  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 INTEL_PT_BLK_SIZE 1024
  28
  29#define BIT63 (((uint64_t)1 << 63))
  30
  31#define INTEL_PT_RETURN 1
  32
  33/* Maximum number of loops with no packets consumed i.e. stuck in a loop */
  34#define INTEL_PT_MAX_LOOPS 10000
  35
  36struct intel_pt_blk {
  37        struct intel_pt_blk *prev;
  38        uint64_t ip[INTEL_PT_BLK_SIZE];
  39};
  40
  41struct intel_pt_stack {
  42        struct intel_pt_blk *blk;
  43        struct intel_pt_blk *spare;
  44        int pos;
  45};
  46
  47enum intel_pt_pkt_state {
  48        INTEL_PT_STATE_NO_PSB,
  49        INTEL_PT_STATE_NO_IP,
  50        INTEL_PT_STATE_ERR_RESYNC,
  51        INTEL_PT_STATE_IN_SYNC,
  52        INTEL_PT_STATE_TNT_CONT,
  53        INTEL_PT_STATE_TNT,
  54        INTEL_PT_STATE_TIP,
  55        INTEL_PT_STATE_TIP_PGD,
  56        INTEL_PT_STATE_FUP,
  57        INTEL_PT_STATE_FUP_NO_TIP,
  58};
  59
  60static inline bool intel_pt_sample_time(enum intel_pt_pkt_state pkt_state)
  61{
  62        switch (pkt_state) {
  63        case INTEL_PT_STATE_NO_PSB:
  64        case INTEL_PT_STATE_NO_IP:
  65        case INTEL_PT_STATE_ERR_RESYNC:
  66        case INTEL_PT_STATE_IN_SYNC:
  67        case INTEL_PT_STATE_TNT_CONT:
  68                return true;
  69        case INTEL_PT_STATE_TNT:
  70        case INTEL_PT_STATE_TIP:
  71        case INTEL_PT_STATE_TIP_PGD:
  72        case INTEL_PT_STATE_FUP:
  73        case INTEL_PT_STATE_FUP_NO_TIP:
  74                return false;
  75        default:
  76                return true;
  77        };
  78}
  79
  80#ifdef INTEL_PT_STRICT
  81#define INTEL_PT_STATE_ERR1     INTEL_PT_STATE_NO_PSB
  82#define INTEL_PT_STATE_ERR2     INTEL_PT_STATE_NO_PSB
  83#define INTEL_PT_STATE_ERR3     INTEL_PT_STATE_NO_PSB
  84#define INTEL_PT_STATE_ERR4     INTEL_PT_STATE_NO_PSB
  85#else
  86#define INTEL_PT_STATE_ERR1     (decoder->pkt_state)
  87#define INTEL_PT_STATE_ERR2     INTEL_PT_STATE_NO_IP
  88#define INTEL_PT_STATE_ERR3     INTEL_PT_STATE_ERR_RESYNC
  89#define INTEL_PT_STATE_ERR4     INTEL_PT_STATE_IN_SYNC
  90#endif
  91
  92struct intel_pt_decoder {
  93        int (*get_trace)(struct intel_pt_buffer *buffer, void *data);
  94        int (*walk_insn)(struct intel_pt_insn *intel_pt_insn,
  95                         uint64_t *insn_cnt_ptr, uint64_t *ip, uint64_t to_ip,
  96                         uint64_t max_insn_cnt, void *data);
  97        bool (*pgd_ip)(uint64_t ip, void *data);
  98        int (*lookahead)(void *data, intel_pt_lookahead_cb_t cb, void *cb_data);
  99        void *data;
 100        struct intel_pt_state state;
 101        const unsigned char *buf;
 102        size_t len;
 103        bool return_compression;
 104        bool branch_enable;
 105        bool mtc_insn;
 106        bool pge;
 107        bool have_tma;
 108        bool have_cyc;
 109        bool fixup_last_mtc;
 110        bool have_last_ip;
 111        bool in_psb;
 112        enum intel_pt_param_flags flags;
 113        uint64_t pos;
 114        uint64_t last_ip;
 115        uint64_t ip;
 116        uint64_t cr3;
 117        uint64_t timestamp;
 118        uint64_t tsc_timestamp;
 119        uint64_t ref_timestamp;
 120        uint64_t buf_timestamp;
 121        uint64_t sample_timestamp;
 122        uint64_t ret_addr;
 123        uint64_t ctc_timestamp;
 124        uint64_t ctc_delta;
 125        uint64_t cycle_cnt;
 126        uint64_t cyc_ref_timestamp;
 127        uint32_t last_mtc;
 128        uint32_t tsc_ctc_ratio_n;
 129        uint32_t tsc_ctc_ratio_d;
 130        uint32_t tsc_ctc_mult;
 131        uint32_t tsc_slip;
 132        uint32_t ctc_rem_mask;
 133        int mtc_shift;
 134        struct intel_pt_stack stack;
 135        enum intel_pt_pkt_state pkt_state;
 136        enum intel_pt_pkt_ctx pkt_ctx;
 137        enum intel_pt_pkt_ctx prev_pkt_ctx;
 138        enum intel_pt_blk_type blk_type;
 139        int blk_type_pos;
 140        struct intel_pt_pkt packet;
 141        struct intel_pt_pkt tnt;
 142        int pkt_step;
 143        int pkt_len;
 144        int last_packet_type;
 145        unsigned int cbr;
 146        unsigned int cbr_seen;
 147        unsigned int max_non_turbo_ratio;
 148        double max_non_turbo_ratio_fp;
 149        double cbr_cyc_to_tsc;
 150        double calc_cyc_to_tsc;
 151        bool have_calc_cyc_to_tsc;
 152        int exec_mode;
 153        unsigned int insn_bytes;
 154        uint64_t period;
 155        enum intel_pt_period_type period_type;
 156        uint64_t tot_insn_cnt;
 157        uint64_t period_insn_cnt;
 158        uint64_t period_mask;
 159        uint64_t period_ticks;
 160        uint64_t last_masked_timestamp;
 161        uint64_t tot_cyc_cnt;
 162        uint64_t sample_tot_cyc_cnt;
 163        uint64_t base_cyc_cnt;
 164        uint64_t cyc_cnt_timestamp;
 165        double tsc_to_cyc;
 166        bool continuous_period;
 167        bool overflow;
 168        bool set_fup_tx_flags;
 169        bool set_fup_ptw;
 170        bool set_fup_mwait;
 171        bool set_fup_pwre;
 172        bool set_fup_exstop;
 173        bool set_fup_bep;
 174        bool sample_cyc;
 175        unsigned int fup_tx_flags;
 176        unsigned int tx_flags;
 177        uint64_t fup_ptw_payload;
 178        uint64_t fup_mwait_payload;
 179        uint64_t fup_pwre_payload;
 180        uint64_t cbr_payload;
 181        uint64_t timestamp_insn_cnt;
 182        uint64_t sample_insn_cnt;
 183        uint64_t stuck_ip;
 184        int no_progress;
 185        int stuck_ip_prd;
 186        int stuck_ip_cnt;
 187        const unsigned char *next_buf;
 188        size_t next_len;
 189        unsigned char temp_buf[INTEL_PT_PKT_MAX_SZ];
 190};
 191
 192static uint64_t intel_pt_lower_power_of_2(uint64_t x)
 193{
 194        int i;
 195
 196        for (i = 0; x != 1; i++)
 197                x >>= 1;
 198
 199        return x << i;
 200}
 201
 202static void intel_pt_setup_period(struct intel_pt_decoder *decoder)
 203{
 204        if (decoder->period_type == INTEL_PT_PERIOD_TICKS) {
 205                uint64_t period;
 206
 207                period = intel_pt_lower_power_of_2(decoder->period);
 208                decoder->period_mask  = ~(period - 1);
 209                decoder->period_ticks = period;
 210        }
 211}
 212
 213static uint64_t multdiv(uint64_t t, uint32_t n, uint32_t d)
 214{
 215        if (!d)
 216                return 0;
 217        return (t / d) * n + ((t % d) * n) / d;
 218}
 219
 220struct intel_pt_decoder *intel_pt_decoder_new(struct intel_pt_params *params)
 221{
 222        struct intel_pt_decoder *decoder;
 223
 224        if (!params->get_trace || !params->walk_insn)
 225                return NULL;
 226
 227        decoder = zalloc(sizeof(struct intel_pt_decoder));
 228        if (!decoder)
 229                return NULL;
 230
 231        decoder->get_trace          = params->get_trace;
 232        decoder->walk_insn          = params->walk_insn;
 233        decoder->pgd_ip             = params->pgd_ip;
 234        decoder->lookahead          = params->lookahead;
 235        decoder->data               = params->data;
 236        decoder->return_compression = params->return_compression;
 237        decoder->branch_enable      = params->branch_enable;
 238
 239        decoder->flags              = params->flags;
 240
 241        decoder->period             = params->period;
 242        decoder->period_type        = params->period_type;
 243
 244        decoder->max_non_turbo_ratio    = params->max_non_turbo_ratio;
 245        decoder->max_non_turbo_ratio_fp = params->max_non_turbo_ratio;
 246
 247        intel_pt_setup_period(decoder);
 248
 249        decoder->mtc_shift = params->mtc_period;
 250        decoder->ctc_rem_mask = (1 << decoder->mtc_shift) - 1;
 251
 252        decoder->tsc_ctc_ratio_n = params->tsc_ctc_ratio_n;
 253        decoder->tsc_ctc_ratio_d = params->tsc_ctc_ratio_d;
 254
 255        if (!decoder->tsc_ctc_ratio_n)
 256                decoder->tsc_ctc_ratio_d = 0;
 257
 258        if (decoder->tsc_ctc_ratio_d) {
 259                if (!(decoder->tsc_ctc_ratio_n % decoder->tsc_ctc_ratio_d))
 260                        decoder->tsc_ctc_mult = decoder->tsc_ctc_ratio_n /
 261                                                decoder->tsc_ctc_ratio_d;
 262        }
 263
 264        /*
 265         * A TSC packet can slip past MTC packets so that the timestamp appears
 266         * to go backwards. One estimate is that can be up to about 40 CPU
 267         * cycles, which is certainly less than 0x1000 TSC ticks, but accept
 268         * slippage an order of magnitude more to be on the safe side.
 269         */
 270        decoder->tsc_slip = 0x10000;
 271
 272        intel_pt_log("timestamp: mtc_shift %u\n", decoder->mtc_shift);
 273        intel_pt_log("timestamp: tsc_ctc_ratio_n %u\n", decoder->tsc_ctc_ratio_n);
 274        intel_pt_log("timestamp: tsc_ctc_ratio_d %u\n", decoder->tsc_ctc_ratio_d);
 275        intel_pt_log("timestamp: tsc_ctc_mult %u\n", decoder->tsc_ctc_mult);
 276        intel_pt_log("timestamp: tsc_slip %#x\n", decoder->tsc_slip);
 277
 278        return decoder;
 279}
 280
 281static void intel_pt_pop_blk(struct intel_pt_stack *stack)
 282{
 283        struct intel_pt_blk *blk = stack->blk;
 284
 285        stack->blk = blk->prev;
 286        if (!stack->spare)
 287                stack->spare = blk;
 288        else
 289                free(blk);
 290}
 291
 292static uint64_t intel_pt_pop(struct intel_pt_stack *stack)
 293{
 294        if (!stack->pos) {
 295                if (!stack->blk)
 296                        return 0;
 297                intel_pt_pop_blk(stack);
 298                if (!stack->blk)
 299                        return 0;
 300                stack->pos = INTEL_PT_BLK_SIZE;
 301        }
 302        return stack->blk->ip[--stack->pos];
 303}
 304
 305static int intel_pt_alloc_blk(struct intel_pt_stack *stack)
 306{
 307        struct intel_pt_blk *blk;
 308
 309        if (stack->spare) {
 310                blk = stack->spare;
 311                stack->spare = NULL;
 312        } else {
 313                blk = malloc(sizeof(struct intel_pt_blk));
 314                if (!blk)
 315                        return -ENOMEM;
 316        }
 317
 318        blk->prev = stack->blk;
 319        stack->blk = blk;
 320        stack->pos = 0;
 321        return 0;
 322}
 323
 324static int intel_pt_push(struct intel_pt_stack *stack, uint64_t ip)
 325{
 326        int err;
 327
 328        if (!stack->blk || stack->pos == INTEL_PT_BLK_SIZE) {
 329                err = intel_pt_alloc_blk(stack);
 330                if (err)
 331                        return err;
 332        }
 333
 334        stack->blk->ip[stack->pos++] = ip;
 335        return 0;
 336}
 337
 338static void intel_pt_clear_stack(struct intel_pt_stack *stack)
 339{
 340        while (stack->blk)
 341                intel_pt_pop_blk(stack);
 342        stack->pos = 0;
 343}
 344
 345static void intel_pt_free_stack(struct intel_pt_stack *stack)
 346{
 347        intel_pt_clear_stack(stack);
 348        zfree(&stack->blk);
 349        zfree(&stack->spare);
 350}
 351
 352void intel_pt_decoder_free(struct intel_pt_decoder *decoder)
 353{
 354        intel_pt_free_stack(&decoder->stack);
 355        free(decoder);
 356}
 357
 358static int intel_pt_ext_err(int code)
 359{
 360        switch (code) {
 361        case -ENOMEM:
 362                return INTEL_PT_ERR_NOMEM;
 363        case -ENOSYS:
 364                return INTEL_PT_ERR_INTERN;
 365        case -EBADMSG:
 366                return INTEL_PT_ERR_BADPKT;
 367        case -ENODATA:
 368                return INTEL_PT_ERR_NODATA;
 369        case -EILSEQ:
 370                return INTEL_PT_ERR_NOINSN;
 371        case -ENOENT:
 372                return INTEL_PT_ERR_MISMAT;
 373        case -EOVERFLOW:
 374                return INTEL_PT_ERR_OVR;
 375        case -ENOSPC:
 376                return INTEL_PT_ERR_LOST;
 377        case -ELOOP:
 378                return INTEL_PT_ERR_NELOOP;
 379        default:
 380                return INTEL_PT_ERR_UNK;
 381        }
 382}
 383
 384static const char *intel_pt_err_msgs[] = {
 385        [INTEL_PT_ERR_NOMEM]  = "Memory allocation failed",
 386        [INTEL_PT_ERR_INTERN] = "Internal error",
 387        [INTEL_PT_ERR_BADPKT] = "Bad packet",
 388        [INTEL_PT_ERR_NODATA] = "No more data",
 389        [INTEL_PT_ERR_NOINSN] = "Failed to get instruction",
 390        [INTEL_PT_ERR_MISMAT] = "Trace doesn't match instruction",
 391        [INTEL_PT_ERR_OVR]    = "Overflow packet",
 392        [INTEL_PT_ERR_LOST]   = "Lost trace data",
 393        [INTEL_PT_ERR_UNK]    = "Unknown error!",
 394        [INTEL_PT_ERR_NELOOP] = "Never-ending loop",
 395};
 396
 397int intel_pt__strerror(int code, char *buf, size_t buflen)
 398{
 399        if (code < 1 || code >= INTEL_PT_ERR_MAX)
 400                code = INTEL_PT_ERR_UNK;
 401        strlcpy(buf, intel_pt_err_msgs[code], buflen);
 402        return 0;
 403}
 404
 405static uint64_t intel_pt_calc_ip(const struct intel_pt_pkt *packet,
 406                                 uint64_t last_ip)
 407{
 408        uint64_t ip;
 409
 410        switch (packet->count) {
 411        case 1:
 412                ip = (last_ip & (uint64_t)0xffffffffffff0000ULL) |
 413                     packet->payload;
 414                break;
 415        case 2:
 416                ip = (last_ip & (uint64_t)0xffffffff00000000ULL) |
 417                     packet->payload;
 418                break;
 419        case 3:
 420                ip = packet->payload;
 421                /* Sign-extend 6-byte ip */
 422                if (ip & (uint64_t)0x800000000000ULL)
 423                        ip |= (uint64_t)0xffff000000000000ULL;
 424                break;
 425        case 4:
 426                ip = (last_ip & (uint64_t)0xffff000000000000ULL) |
 427                     packet->payload;
 428                break;
 429        case 6:
 430                ip = packet->payload;
 431                break;
 432        default:
 433                return 0;
 434        }
 435
 436        return ip;
 437}
 438
 439static inline void intel_pt_set_last_ip(struct intel_pt_decoder *decoder)
 440{
 441        decoder->last_ip = intel_pt_calc_ip(&decoder->packet, decoder->last_ip);
 442        decoder->have_last_ip = true;
 443}
 444
 445static inline void intel_pt_set_ip(struct intel_pt_decoder *decoder)
 446{
 447        intel_pt_set_last_ip(decoder);
 448        decoder->ip = decoder->last_ip;
 449}
 450
 451static void intel_pt_decoder_log_packet(struct intel_pt_decoder *decoder)
 452{
 453        intel_pt_log_packet(&decoder->packet, decoder->pkt_len, decoder->pos,
 454                            decoder->buf);
 455}
 456
 457static int intel_pt_bug(struct intel_pt_decoder *decoder)
 458{
 459        intel_pt_log("ERROR: Internal error\n");
 460        decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
 461        return -ENOSYS;
 462}
 463
 464static inline void intel_pt_clear_tx_flags(struct intel_pt_decoder *decoder)
 465{
 466        decoder->tx_flags = 0;
 467}
 468
 469static inline void intel_pt_update_in_tx(struct intel_pt_decoder *decoder)
 470{
 471        decoder->tx_flags = decoder->packet.payload & INTEL_PT_IN_TX;
 472}
 473
 474static int intel_pt_bad_packet(struct intel_pt_decoder *decoder)
 475{
 476        intel_pt_clear_tx_flags(decoder);
 477        decoder->have_tma = false;
 478        decoder->pkt_len = 1;
 479        decoder->pkt_step = 1;
 480        intel_pt_decoder_log_packet(decoder);
 481        if (decoder->pkt_state != INTEL_PT_STATE_NO_PSB) {
 482                intel_pt_log("ERROR: Bad packet\n");
 483                decoder->pkt_state = INTEL_PT_STATE_ERR1;
 484        }
 485        return -EBADMSG;
 486}
 487
 488static inline void intel_pt_update_sample_time(struct intel_pt_decoder *decoder)
 489{
 490        decoder->sample_timestamp = decoder->timestamp;
 491        decoder->sample_insn_cnt = decoder->timestamp_insn_cnt;
 492}
 493
 494static void intel_pt_reposition(struct intel_pt_decoder *decoder)
 495{
 496        decoder->ip = 0;
 497        decoder->pkt_state = INTEL_PT_STATE_NO_PSB;
 498        decoder->timestamp = 0;
 499        decoder->have_tma = false;
 500}
 501
 502static int intel_pt_get_data(struct intel_pt_decoder *decoder, bool reposition)
 503{
 504        struct intel_pt_buffer buffer = { .buf = 0, };
 505        int ret;
 506
 507        decoder->pkt_step = 0;
 508
 509        intel_pt_log("Getting more data\n");
 510        ret = decoder->get_trace(&buffer, decoder->data);
 511        if (ret)
 512                return ret;
 513        decoder->buf = buffer.buf;
 514        decoder->len = buffer.len;
 515        if (!decoder->len) {
 516                intel_pt_log("No more data\n");
 517                return -ENODATA;
 518        }
 519        decoder->buf_timestamp = buffer.ref_timestamp;
 520        if (!buffer.consecutive || reposition) {
 521                intel_pt_reposition(decoder);
 522                decoder->ref_timestamp = buffer.ref_timestamp;
 523                decoder->state.trace_nr = buffer.trace_nr;
 524                intel_pt_log("Reference timestamp 0x%" PRIx64 "\n",
 525                             decoder->ref_timestamp);
 526                return -ENOLINK;
 527        }
 528
 529        return 0;
 530}
 531
 532static int intel_pt_get_next_data(struct intel_pt_decoder *decoder,
 533                                  bool reposition)
 534{
 535        if (!decoder->next_buf)
 536                return intel_pt_get_data(decoder, reposition);
 537
 538        decoder->buf = decoder->next_buf;
 539        decoder->len = decoder->next_len;
 540        decoder->next_buf = 0;
 541        decoder->next_len = 0;
 542        return 0;
 543}
 544
 545static int intel_pt_get_split_packet(struct intel_pt_decoder *decoder)
 546{
 547        unsigned char *buf = decoder->temp_buf;
 548        size_t old_len, len, n;
 549        int ret;
 550
 551        old_len = decoder->len;
 552        len = decoder->len;
 553        memcpy(buf, decoder->buf, len);
 554
 555        ret = intel_pt_get_data(decoder, false);
 556        if (ret) {
 557                decoder->pos += old_len;
 558                return ret < 0 ? ret : -EINVAL;
 559        }
 560
 561        n = INTEL_PT_PKT_MAX_SZ - len;
 562        if (n > decoder->len)
 563                n = decoder->len;
 564        memcpy(buf + len, decoder->buf, n);
 565        len += n;
 566
 567        decoder->prev_pkt_ctx = decoder->pkt_ctx;
 568        ret = intel_pt_get_packet(buf, len, &decoder->packet, &decoder->pkt_ctx);
 569        if (ret < (int)old_len) {
 570                decoder->next_buf = decoder->buf;
 571                decoder->next_len = decoder->len;
 572                decoder->buf = buf;
 573                decoder->len = old_len;
 574                return intel_pt_bad_packet(decoder);
 575        }
 576
 577        decoder->next_buf = decoder->buf + (ret - old_len);
 578        decoder->next_len = decoder->len - (ret - old_len);
 579
 580        decoder->buf = buf;
 581        decoder->len = ret;
 582
 583        return ret;
 584}
 585
 586struct intel_pt_pkt_info {
 587        struct intel_pt_decoder   *decoder;
 588        struct intel_pt_pkt       packet;
 589        uint64_t                  pos;
 590        int                       pkt_len;
 591        int                       last_packet_type;
 592        void                      *data;
 593};
 594
 595typedef int (*intel_pt_pkt_cb_t)(struct intel_pt_pkt_info *pkt_info);
 596
 597/* Lookahead packets in current buffer */
 598static int intel_pt_pkt_lookahead(struct intel_pt_decoder *decoder,
 599                                  intel_pt_pkt_cb_t cb, void *data)
 600{
 601        struct intel_pt_pkt_info pkt_info;
 602        const unsigned char *buf = decoder->buf;
 603        enum intel_pt_pkt_ctx pkt_ctx = decoder->pkt_ctx;
 604        size_t len = decoder->len;
 605        int ret;
 606
 607        pkt_info.decoder          = decoder;
 608        pkt_info.pos              = decoder->pos;
 609        pkt_info.pkt_len          = decoder->pkt_step;
 610        pkt_info.last_packet_type = decoder->last_packet_type;
 611        pkt_info.data             = data;
 612
 613        while (1) {
 614                do {
 615                        pkt_info.pos += pkt_info.pkt_len;
 616                        buf          += pkt_info.pkt_len;
 617                        len          -= pkt_info.pkt_len;
 618
 619                        if (!len)
 620                                return INTEL_PT_NEED_MORE_BYTES;
 621
 622                        ret = intel_pt_get_packet(buf, len, &pkt_info.packet,
 623                                                  &pkt_ctx);
 624                        if (!ret)
 625                                return INTEL_PT_NEED_MORE_BYTES;
 626                        if (ret < 0)
 627                                return ret;
 628
 629                        pkt_info.pkt_len = ret;
 630                } while (pkt_info.packet.type == INTEL_PT_PAD);
 631
 632                ret = cb(&pkt_info);
 633                if (ret)
 634                        return 0;
 635
 636                pkt_info.last_packet_type = pkt_info.packet.type;
 637        }
 638}
 639
 640struct intel_pt_calc_cyc_to_tsc_info {
 641        uint64_t        cycle_cnt;
 642        unsigned int    cbr;
 643        uint32_t        last_mtc;
 644        uint64_t        ctc_timestamp;
 645        uint64_t        ctc_delta;
 646        uint64_t        tsc_timestamp;
 647        uint64_t        timestamp;
 648        bool            have_tma;
 649        bool            fixup_last_mtc;
 650        bool            from_mtc;
 651        double          cbr_cyc_to_tsc;
 652};
 653
 654/*
 655 * MTC provides a 8-bit slice of CTC but the TMA packet only provides the lower
 656 * 16 bits of CTC. If mtc_shift > 8 then some of the MTC bits are not in the CTC
 657 * provided by the TMA packet. Fix-up the last_mtc calculated from the TMA
 658 * packet by copying the missing bits from the current MTC assuming the least
 659 * difference between the two, and that the current MTC comes after last_mtc.
 660 */
 661static void intel_pt_fixup_last_mtc(uint32_t mtc, int mtc_shift,
 662                                    uint32_t *last_mtc)
 663{
 664        uint32_t first_missing_bit = 1U << (16 - mtc_shift);
 665        uint32_t mask = ~(first_missing_bit - 1);
 666
 667        *last_mtc |= mtc & mask;
 668        if (*last_mtc >= mtc) {
 669                *last_mtc -= first_missing_bit;
 670                *last_mtc &= 0xff;
 671        }
 672}
 673
 674static int intel_pt_calc_cyc_cb(struct intel_pt_pkt_info *pkt_info)
 675{
 676        struct intel_pt_decoder *decoder = pkt_info->decoder;
 677        struct intel_pt_calc_cyc_to_tsc_info *data = pkt_info->data;
 678        uint64_t timestamp;
 679        double cyc_to_tsc;
 680        unsigned int cbr;
 681        uint32_t mtc, mtc_delta, ctc, fc, ctc_rem;
 682
 683        switch (pkt_info->packet.type) {
 684        case INTEL_PT_TNT:
 685        case INTEL_PT_TIP_PGE:
 686        case INTEL_PT_TIP:
 687        case INTEL_PT_FUP:
 688        case INTEL_PT_PSB:
 689        case INTEL_PT_PIP:
 690        case INTEL_PT_MODE_EXEC:
 691        case INTEL_PT_MODE_TSX:
 692        case INTEL_PT_PSBEND:
 693        case INTEL_PT_PAD:
 694        case INTEL_PT_VMCS:
 695        case INTEL_PT_MNT:
 696        case INTEL_PT_PTWRITE:
 697        case INTEL_PT_PTWRITE_IP:
 698        case INTEL_PT_BBP:
 699        case INTEL_PT_BIP:
 700        case INTEL_PT_BEP:
 701        case INTEL_PT_BEP_IP:
 702                return 0;
 703
 704        case INTEL_PT_MTC:
 705                if (!data->have_tma)
 706                        return 0;
 707
 708                mtc = pkt_info->packet.payload;
 709                if (decoder->mtc_shift > 8 && data->fixup_last_mtc) {
 710                        data->fixup_last_mtc = false;
 711                        intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
 712                                                &data->last_mtc);
 713                }
 714                if (mtc > data->last_mtc)
 715                        mtc_delta = mtc - data->last_mtc;
 716                else
 717                        mtc_delta = mtc + 256 - data->last_mtc;
 718                data->ctc_delta += mtc_delta << decoder->mtc_shift;
 719                data->last_mtc = mtc;
 720
 721                if (decoder->tsc_ctc_mult) {
 722                        timestamp = data->ctc_timestamp +
 723                                data->ctc_delta * decoder->tsc_ctc_mult;
 724                } else {
 725                        timestamp = data->ctc_timestamp +
 726                                multdiv(data->ctc_delta,
 727                                        decoder->tsc_ctc_ratio_n,
 728                                        decoder->tsc_ctc_ratio_d);
 729                }
 730
 731                if (timestamp < data->timestamp)
 732                        return 1;
 733
 734                if (pkt_info->last_packet_type != INTEL_PT_CYC) {
 735                        data->timestamp = timestamp;
 736                        return 0;
 737                }
 738
 739                break;
 740
 741        case INTEL_PT_TSC:
 742                /*
 743                 * For now, do not support using TSC packets - refer
 744                 * intel_pt_calc_cyc_to_tsc().
 745                 */
 746                if (data->from_mtc)
 747                        return 1;
 748                timestamp = pkt_info->packet.payload |
 749                            (data->timestamp & (0xffULL << 56));
 750                if (data->from_mtc && timestamp < data->timestamp &&
 751                    data->timestamp - timestamp < decoder->tsc_slip)
 752                        return 1;
 753                if (timestamp < data->timestamp)
 754                        timestamp += (1ULL << 56);
 755                if (pkt_info->last_packet_type != INTEL_PT_CYC) {
 756                        if (data->from_mtc)
 757                                return 1;
 758                        data->tsc_timestamp = timestamp;
 759                        data->timestamp = timestamp;
 760                        return 0;
 761                }
 762                break;
 763
 764        case INTEL_PT_TMA:
 765                if (data->from_mtc)
 766                        return 1;
 767
 768                if (!decoder->tsc_ctc_ratio_d)
 769                        return 0;
 770
 771                ctc = pkt_info->packet.payload;
 772                fc = pkt_info->packet.count;
 773                ctc_rem = ctc & decoder->ctc_rem_mask;
 774
 775                data->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
 776
 777                data->ctc_timestamp = data->tsc_timestamp - fc;
 778                if (decoder->tsc_ctc_mult) {
 779                        data->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
 780                } else {
 781                        data->ctc_timestamp -=
 782                                multdiv(ctc_rem, decoder->tsc_ctc_ratio_n,
 783                                        decoder->tsc_ctc_ratio_d);
 784                }
 785
 786                data->ctc_delta = 0;
 787                data->have_tma = true;
 788                data->fixup_last_mtc = true;
 789
 790                return 0;
 791
 792        case INTEL_PT_CYC:
 793                data->cycle_cnt += pkt_info->packet.payload;
 794                return 0;
 795
 796        case INTEL_PT_CBR:
 797                cbr = pkt_info->packet.payload;
 798                if (data->cbr && data->cbr != cbr)
 799                        return 1;
 800                data->cbr = cbr;
 801                data->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
 802                return 0;
 803
 804        case INTEL_PT_TIP_PGD:
 805        case INTEL_PT_TRACESTOP:
 806        case INTEL_PT_EXSTOP:
 807        case INTEL_PT_EXSTOP_IP:
 808        case INTEL_PT_MWAIT:
 809        case INTEL_PT_PWRE:
 810        case INTEL_PT_PWRX:
 811        case INTEL_PT_OVF:
 812        case INTEL_PT_BAD: /* Does not happen */
 813        default:
 814                return 1;
 815        }
 816
 817        if (!data->cbr && decoder->cbr) {
 818                data->cbr = decoder->cbr;
 819                data->cbr_cyc_to_tsc = decoder->cbr_cyc_to_tsc;
 820        }
 821
 822        if (!data->cycle_cnt)
 823                return 1;
 824
 825        cyc_to_tsc = (double)(timestamp - decoder->timestamp) / data->cycle_cnt;
 826
 827        if (data->cbr && cyc_to_tsc > data->cbr_cyc_to_tsc &&
 828            cyc_to_tsc / data->cbr_cyc_to_tsc > 1.25) {
 829                intel_pt_log("Timestamp: calculated %g TSC ticks per cycle too big (c.f. CBR-based value %g), pos " x64_fmt "\n",
 830                             cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
 831                return 1;
 832        }
 833
 834        decoder->calc_cyc_to_tsc = cyc_to_tsc;
 835        decoder->have_calc_cyc_to_tsc = true;
 836
 837        if (data->cbr) {
 838                intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. CBR-based value %g, pos " x64_fmt "\n",
 839                             cyc_to_tsc, data->cbr_cyc_to_tsc, pkt_info->pos);
 840        } else {
 841                intel_pt_log("Timestamp: calculated %g TSC ticks per cycle c.f. unknown CBR-based value, pos " x64_fmt "\n",
 842                             cyc_to_tsc, pkt_info->pos);
 843        }
 844
 845        return 1;
 846}
 847
 848static void intel_pt_calc_cyc_to_tsc(struct intel_pt_decoder *decoder,
 849                                     bool from_mtc)
 850{
 851        struct intel_pt_calc_cyc_to_tsc_info data = {
 852                .cycle_cnt      = 0,
 853                .cbr            = 0,
 854                .last_mtc       = decoder->last_mtc,
 855                .ctc_timestamp  = decoder->ctc_timestamp,
 856                .ctc_delta      = decoder->ctc_delta,
 857                .tsc_timestamp  = decoder->tsc_timestamp,
 858                .timestamp      = decoder->timestamp,
 859                .have_tma       = decoder->have_tma,
 860                .fixup_last_mtc = decoder->fixup_last_mtc,
 861                .from_mtc       = from_mtc,
 862                .cbr_cyc_to_tsc = 0,
 863        };
 864
 865        /*
 866         * For now, do not support using TSC packets for at least the reasons:
 867         * 1) timing might have stopped
 868         * 2) TSC packets within PSB+ can slip against CYC packets
 869         */
 870        if (!from_mtc)
 871                return;
 872
 873        intel_pt_pkt_lookahead(decoder, intel_pt_calc_cyc_cb, &data);
 874}
 875
 876static int intel_pt_get_next_packet(struct intel_pt_decoder *decoder)
 877{
 878        int ret;
 879
 880        decoder->last_packet_type = decoder->packet.type;
 881
 882        do {
 883                decoder->pos += decoder->pkt_step;
 884                decoder->buf += decoder->pkt_step;
 885                decoder->len -= decoder->pkt_step;
 886
 887                if (!decoder->len) {
 888                        ret = intel_pt_get_next_data(decoder, false);
 889                        if (ret)
 890                                return ret;
 891                }
 892
 893                decoder->prev_pkt_ctx = decoder->pkt_ctx;
 894                ret = intel_pt_get_packet(decoder->buf, decoder->len,
 895                                          &decoder->packet, &decoder->pkt_ctx);
 896                if (ret == INTEL_PT_NEED_MORE_BYTES && BITS_PER_LONG == 32 &&
 897                    decoder->len < INTEL_PT_PKT_MAX_SZ && !decoder->next_buf) {
 898                        ret = intel_pt_get_split_packet(decoder);
 899                        if (ret < 0)
 900                                return ret;
 901                }
 902                if (ret <= 0)
 903                        return intel_pt_bad_packet(decoder);
 904
 905                decoder->pkt_len = ret;
 906                decoder->pkt_step = ret;
 907                intel_pt_decoder_log_packet(decoder);
 908        } while (decoder->packet.type == INTEL_PT_PAD);
 909
 910        return 0;
 911}
 912
 913static uint64_t intel_pt_next_period(struct intel_pt_decoder *decoder)
 914{
 915        uint64_t timestamp, masked_timestamp;
 916
 917        timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
 918        masked_timestamp = timestamp & decoder->period_mask;
 919        if (decoder->continuous_period) {
 920                if (masked_timestamp > decoder->last_masked_timestamp)
 921                        return 1;
 922        } else {
 923                timestamp += 1;
 924                masked_timestamp = timestamp & decoder->period_mask;
 925                if (masked_timestamp > decoder->last_masked_timestamp) {
 926                        decoder->last_masked_timestamp = masked_timestamp;
 927                        decoder->continuous_period = true;
 928                }
 929        }
 930
 931        if (masked_timestamp < decoder->last_masked_timestamp)
 932                return decoder->period_ticks;
 933
 934        return decoder->period_ticks - (timestamp - masked_timestamp);
 935}
 936
 937static uint64_t intel_pt_next_sample(struct intel_pt_decoder *decoder)
 938{
 939        switch (decoder->period_type) {
 940        case INTEL_PT_PERIOD_INSTRUCTIONS:
 941                return decoder->period - decoder->period_insn_cnt;
 942        case INTEL_PT_PERIOD_TICKS:
 943                return intel_pt_next_period(decoder);
 944        case INTEL_PT_PERIOD_NONE:
 945        case INTEL_PT_PERIOD_MTC:
 946        default:
 947                return 0;
 948        }
 949}
 950
 951static void intel_pt_sample_insn(struct intel_pt_decoder *decoder)
 952{
 953        uint64_t timestamp, masked_timestamp;
 954
 955        switch (decoder->period_type) {
 956        case INTEL_PT_PERIOD_INSTRUCTIONS:
 957                decoder->period_insn_cnt = 0;
 958                break;
 959        case INTEL_PT_PERIOD_TICKS:
 960                timestamp = decoder->timestamp + decoder->timestamp_insn_cnt;
 961                masked_timestamp = timestamp & decoder->period_mask;
 962                if (masked_timestamp > decoder->last_masked_timestamp)
 963                        decoder->last_masked_timestamp = masked_timestamp;
 964                else
 965                        decoder->last_masked_timestamp += decoder->period_ticks;
 966                break;
 967        case INTEL_PT_PERIOD_NONE:
 968        case INTEL_PT_PERIOD_MTC:
 969        default:
 970                break;
 971        }
 972
 973        decoder->state.type |= INTEL_PT_INSTRUCTION;
 974}
 975
 976static int intel_pt_walk_insn(struct intel_pt_decoder *decoder,
 977                              struct intel_pt_insn *intel_pt_insn, uint64_t ip)
 978{
 979        uint64_t max_insn_cnt, insn_cnt = 0;
 980        int err;
 981
 982        if (!decoder->mtc_insn)
 983                decoder->mtc_insn = true;
 984
 985        max_insn_cnt = intel_pt_next_sample(decoder);
 986
 987        err = decoder->walk_insn(intel_pt_insn, &insn_cnt, &decoder->ip, ip,
 988                                 max_insn_cnt, decoder->data);
 989
 990        decoder->tot_insn_cnt += insn_cnt;
 991        decoder->timestamp_insn_cnt += insn_cnt;
 992        decoder->sample_insn_cnt += insn_cnt;
 993        decoder->period_insn_cnt += insn_cnt;
 994
 995        if (err) {
 996                decoder->no_progress = 0;
 997                decoder->pkt_state = INTEL_PT_STATE_ERR2;
 998                intel_pt_log_at("ERROR: Failed to get instruction",
 999                                decoder->ip);
1000                if (err == -ENOENT)
1001                        return -ENOLINK;
1002                return -EILSEQ;
1003        }
1004
1005        if (ip && decoder->ip == ip) {
1006                err = -EAGAIN;
1007                goto out;
1008        }
1009
1010        if (max_insn_cnt && insn_cnt >= max_insn_cnt)
1011                intel_pt_sample_insn(decoder);
1012
1013        if (intel_pt_insn->branch == INTEL_PT_BR_NO_BRANCH) {
1014                decoder->state.type = INTEL_PT_INSTRUCTION;
1015                decoder->state.from_ip = decoder->ip;
1016                decoder->state.to_ip = 0;
1017                decoder->ip += intel_pt_insn->length;
1018                err = INTEL_PT_RETURN;
1019                goto out;
1020        }
1021
1022        if (intel_pt_insn->op == INTEL_PT_OP_CALL) {
1023                /* Zero-length calls are excluded */
1024                if (intel_pt_insn->branch != INTEL_PT_BR_UNCONDITIONAL ||
1025                    intel_pt_insn->rel) {
1026                        err = intel_pt_push(&decoder->stack, decoder->ip +
1027                                            intel_pt_insn->length);
1028                        if (err)
1029                                goto out;
1030                }
1031        } else if (intel_pt_insn->op == INTEL_PT_OP_RET) {
1032                decoder->ret_addr = intel_pt_pop(&decoder->stack);
1033        }
1034
1035        if (intel_pt_insn->branch == INTEL_PT_BR_UNCONDITIONAL) {
1036                int cnt = decoder->no_progress++;
1037
1038                decoder->state.from_ip = decoder->ip;
1039                decoder->ip += intel_pt_insn->length +
1040                                intel_pt_insn->rel;
1041                decoder->state.to_ip = decoder->ip;
1042                err = INTEL_PT_RETURN;
1043
1044                /*
1045                 * Check for being stuck in a loop.  This can happen if a
1046                 * decoder error results in the decoder erroneously setting the
1047                 * ip to an address that is itself in an infinite loop that
1048                 * consumes no packets.  When that happens, there must be an
1049                 * unconditional branch.
1050                 */
1051                if (cnt) {
1052                        if (cnt == 1) {
1053                                decoder->stuck_ip = decoder->state.to_ip;
1054                                decoder->stuck_ip_prd = 1;
1055                                decoder->stuck_ip_cnt = 1;
1056                        } else if (cnt > INTEL_PT_MAX_LOOPS ||
1057                                   decoder->state.to_ip == decoder->stuck_ip) {
1058                                intel_pt_log_at("ERROR: Never-ending loop",
1059                                                decoder->state.to_ip);
1060                                decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1061                                err = -ELOOP;
1062                                goto out;
1063                        } else if (!--decoder->stuck_ip_cnt) {
1064                                decoder->stuck_ip_prd += 1;
1065                                decoder->stuck_ip_cnt = decoder->stuck_ip_prd;
1066                                decoder->stuck_ip = decoder->state.to_ip;
1067                        }
1068                }
1069                goto out_no_progress;
1070        }
1071out:
1072        decoder->no_progress = 0;
1073out_no_progress:
1074        decoder->state.insn_op = intel_pt_insn->op;
1075        decoder->state.insn_len = intel_pt_insn->length;
1076        memcpy(decoder->state.insn, intel_pt_insn->buf,
1077               INTEL_PT_INSN_BUF_SZ);
1078
1079        if (decoder->tx_flags & INTEL_PT_IN_TX)
1080                decoder->state.flags |= INTEL_PT_IN_TX;
1081
1082        return err;
1083}
1084
1085static bool intel_pt_fup_event(struct intel_pt_decoder *decoder)
1086{
1087        bool ret = false;
1088
1089        if (decoder->set_fup_tx_flags) {
1090                decoder->set_fup_tx_flags = false;
1091                decoder->tx_flags = decoder->fup_tx_flags;
1092                decoder->state.type = INTEL_PT_TRANSACTION;
1093                decoder->state.from_ip = decoder->ip;
1094                decoder->state.to_ip = 0;
1095                decoder->state.flags = decoder->fup_tx_flags;
1096                return true;
1097        }
1098        if (decoder->set_fup_ptw) {
1099                decoder->set_fup_ptw = false;
1100                decoder->state.type = INTEL_PT_PTW;
1101                decoder->state.flags |= INTEL_PT_FUP_IP;
1102                decoder->state.from_ip = decoder->ip;
1103                decoder->state.to_ip = 0;
1104                decoder->state.ptw_payload = decoder->fup_ptw_payload;
1105                return true;
1106        }
1107        if (decoder->set_fup_mwait) {
1108                decoder->set_fup_mwait = false;
1109                decoder->state.type = INTEL_PT_MWAIT_OP;
1110                decoder->state.from_ip = decoder->ip;
1111                decoder->state.to_ip = 0;
1112                decoder->state.mwait_payload = decoder->fup_mwait_payload;
1113                ret = true;
1114        }
1115        if (decoder->set_fup_pwre) {
1116                decoder->set_fup_pwre = false;
1117                decoder->state.type |= INTEL_PT_PWR_ENTRY;
1118                decoder->state.type &= ~INTEL_PT_BRANCH;
1119                decoder->state.from_ip = decoder->ip;
1120                decoder->state.to_ip = 0;
1121                decoder->state.pwre_payload = decoder->fup_pwre_payload;
1122                ret = true;
1123        }
1124        if (decoder->set_fup_exstop) {
1125                decoder->set_fup_exstop = false;
1126                decoder->state.type |= INTEL_PT_EX_STOP;
1127                decoder->state.type &= ~INTEL_PT_BRANCH;
1128                decoder->state.flags |= INTEL_PT_FUP_IP;
1129                decoder->state.from_ip = decoder->ip;
1130                decoder->state.to_ip = 0;
1131                ret = true;
1132        }
1133        if (decoder->set_fup_bep) {
1134                decoder->set_fup_bep = false;
1135                decoder->state.type |= INTEL_PT_BLK_ITEMS;
1136                decoder->state.type &= ~INTEL_PT_BRANCH;
1137                decoder->state.from_ip = decoder->ip;
1138                decoder->state.to_ip = 0;
1139                ret = true;
1140        }
1141        return ret;
1142}
1143
1144static inline bool intel_pt_fup_with_nlip(struct intel_pt_decoder *decoder,
1145                                          struct intel_pt_insn *intel_pt_insn,
1146                                          uint64_t ip, int err)
1147{
1148        return decoder->flags & INTEL_PT_FUP_WITH_NLIP && !err &&
1149               intel_pt_insn->branch == INTEL_PT_BR_INDIRECT &&
1150               ip == decoder->ip + intel_pt_insn->length;
1151}
1152
1153static int intel_pt_walk_fup(struct intel_pt_decoder *decoder)
1154{
1155        struct intel_pt_insn intel_pt_insn;
1156        uint64_t ip;
1157        int err;
1158
1159        ip = decoder->last_ip;
1160
1161        while (1) {
1162                err = intel_pt_walk_insn(decoder, &intel_pt_insn, ip);
1163                if (err == INTEL_PT_RETURN)
1164                        return 0;
1165                if (err == -EAGAIN ||
1166                    intel_pt_fup_with_nlip(decoder, &intel_pt_insn, ip, err)) {
1167                        if (intel_pt_fup_event(decoder))
1168                                return 0;
1169                        return -EAGAIN;
1170                }
1171                decoder->set_fup_tx_flags = false;
1172                if (err)
1173                        return err;
1174
1175                if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1176                        intel_pt_log_at("ERROR: Unexpected indirect branch",
1177                                        decoder->ip);
1178                        decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1179                        return -ENOENT;
1180                }
1181
1182                if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1183                        intel_pt_log_at("ERROR: Unexpected conditional branch",
1184                                        decoder->ip);
1185                        decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1186                        return -ENOENT;
1187                }
1188
1189                intel_pt_bug(decoder);
1190        }
1191}
1192
1193static int intel_pt_walk_tip(struct intel_pt_decoder *decoder)
1194{
1195        struct intel_pt_insn intel_pt_insn;
1196        int err;
1197
1198        err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1199        if (err == INTEL_PT_RETURN &&
1200            decoder->pgd_ip &&
1201            decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1202            (decoder->state.type & INTEL_PT_BRANCH) &&
1203            decoder->pgd_ip(decoder->state.to_ip, decoder->data)) {
1204                /* Unconditional branch leaving filter region */
1205                decoder->no_progress = 0;
1206                decoder->pge = false;
1207                decoder->continuous_period = false;
1208                decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1209                decoder->state.type |= INTEL_PT_TRACE_END;
1210                return 0;
1211        }
1212        if (err == INTEL_PT_RETURN)
1213                return 0;
1214        if (err)
1215                return err;
1216
1217        if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1218                if (decoder->pkt_state == INTEL_PT_STATE_TIP_PGD) {
1219                        decoder->pge = false;
1220                        decoder->continuous_period = false;
1221                        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1222                        decoder->state.from_ip = decoder->ip;
1223                        if (decoder->packet.count == 0) {
1224                                decoder->state.to_ip = 0;
1225                        } else {
1226                                decoder->state.to_ip = decoder->last_ip;
1227                                decoder->ip = decoder->last_ip;
1228                        }
1229                        decoder->state.type |= INTEL_PT_TRACE_END;
1230                } else {
1231                        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1232                        decoder->state.from_ip = decoder->ip;
1233                        if (decoder->packet.count == 0) {
1234                                decoder->state.to_ip = 0;
1235                        } else {
1236                                decoder->state.to_ip = decoder->last_ip;
1237                                decoder->ip = decoder->last_ip;
1238                        }
1239                }
1240                return 0;
1241        }
1242
1243        if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1244                uint64_t to_ip = decoder->ip + intel_pt_insn.length +
1245                                 intel_pt_insn.rel;
1246
1247                if (decoder->pgd_ip &&
1248                    decoder->pkt_state == INTEL_PT_STATE_TIP_PGD &&
1249                    decoder->pgd_ip(to_ip, decoder->data)) {
1250                        /* Conditional branch leaving filter region */
1251                        decoder->pge = false;
1252                        decoder->continuous_period = false;
1253                        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1254                        decoder->ip = to_ip;
1255                        decoder->state.from_ip = decoder->ip;
1256                        decoder->state.to_ip = to_ip;
1257                        decoder->state.type |= INTEL_PT_TRACE_END;
1258                        return 0;
1259                }
1260                intel_pt_log_at("ERROR: Conditional branch when expecting indirect branch",
1261                                decoder->ip);
1262                decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1263                return -ENOENT;
1264        }
1265
1266        return intel_pt_bug(decoder);
1267}
1268
1269static int intel_pt_walk_tnt(struct intel_pt_decoder *decoder)
1270{
1271        struct intel_pt_insn intel_pt_insn;
1272        int err;
1273
1274        while (1) {
1275                err = intel_pt_walk_insn(decoder, &intel_pt_insn, 0);
1276                if (err == INTEL_PT_RETURN)
1277                        return 0;
1278                if (err)
1279                        return err;
1280
1281                if (intel_pt_insn.op == INTEL_PT_OP_RET) {
1282                        if (!decoder->return_compression) {
1283                                intel_pt_log_at("ERROR: RET when expecting conditional branch",
1284                                                decoder->ip);
1285                                decoder->pkt_state = INTEL_PT_STATE_ERR3;
1286                                return -ENOENT;
1287                        }
1288                        if (!decoder->ret_addr) {
1289                                intel_pt_log_at("ERROR: Bad RET compression (stack empty)",
1290                                                decoder->ip);
1291                                decoder->pkt_state = INTEL_PT_STATE_ERR3;
1292                                return -ENOENT;
1293                        }
1294                        if (!(decoder->tnt.payload & BIT63)) {
1295                                intel_pt_log_at("ERROR: Bad RET compression (TNT=N)",
1296                                                decoder->ip);
1297                                decoder->pkt_state = INTEL_PT_STATE_ERR3;
1298                                return -ENOENT;
1299                        }
1300                        decoder->tnt.count -= 1;
1301                        if (decoder->tnt.count)
1302                                decoder->pkt_state = INTEL_PT_STATE_TNT_CONT;
1303                        else
1304                                decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1305                        decoder->tnt.payload <<= 1;
1306                        decoder->state.from_ip = decoder->ip;
1307                        decoder->ip = decoder->ret_addr;
1308                        decoder->state.to_ip = decoder->ip;
1309                        return 0;
1310                }
1311
1312                if (intel_pt_insn.branch == INTEL_PT_BR_INDIRECT) {
1313                        /* Handle deferred TIPs */
1314                        err = intel_pt_get_next_packet(decoder);
1315                        if (err)
1316                                return err;
1317                        if (decoder->packet.type != INTEL_PT_TIP ||
1318                            decoder->packet.count == 0) {
1319                                intel_pt_log_at("ERROR: Missing deferred TIP for indirect branch",
1320                                                decoder->ip);
1321                                decoder->pkt_state = INTEL_PT_STATE_ERR3;
1322                                decoder->pkt_step = 0;
1323                                return -ENOENT;
1324                        }
1325                        intel_pt_set_last_ip(decoder);
1326                        decoder->state.from_ip = decoder->ip;
1327                        decoder->state.to_ip = decoder->last_ip;
1328                        decoder->ip = decoder->last_ip;
1329                        return 0;
1330                }
1331
1332                if (intel_pt_insn.branch == INTEL_PT_BR_CONDITIONAL) {
1333                        decoder->tnt.count -= 1;
1334                        if (decoder->tnt.count)
1335                                decoder->pkt_state = INTEL_PT_STATE_TNT_CONT;
1336                        else
1337                                decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
1338                        if (decoder->tnt.payload & BIT63) {
1339                                decoder->tnt.payload <<= 1;
1340                                decoder->state.from_ip = decoder->ip;
1341                                decoder->ip += intel_pt_insn.length +
1342                                               intel_pt_insn.rel;
1343                                decoder->state.to_ip = decoder->ip;
1344                                return 0;
1345                        }
1346                        /* Instruction sample for a non-taken branch */
1347                        if (decoder->state.type & INTEL_PT_INSTRUCTION) {
1348                                decoder->tnt.payload <<= 1;
1349                                decoder->state.type = INTEL_PT_INSTRUCTION;
1350                                decoder->state.from_ip = decoder->ip;
1351                                decoder->state.to_ip = 0;
1352                                decoder->ip += intel_pt_insn.length;
1353                                return 0;
1354                        }
1355                        decoder->sample_cyc = false;
1356                        decoder->ip += intel_pt_insn.length;
1357                        if (!decoder->tnt.count) {
1358                                intel_pt_update_sample_time(decoder);
1359                                return -EAGAIN;
1360                        }
1361                        decoder->tnt.payload <<= 1;
1362                        continue;
1363                }
1364
1365                return intel_pt_bug(decoder);
1366        }
1367}
1368
1369static int intel_pt_mode_tsx(struct intel_pt_decoder *decoder, bool *no_tip)
1370{
1371        unsigned int fup_tx_flags;
1372        int err;
1373
1374        fup_tx_flags = decoder->packet.payload &
1375                       (INTEL_PT_IN_TX | INTEL_PT_ABORT_TX);
1376        err = intel_pt_get_next_packet(decoder);
1377        if (err)
1378                return err;
1379        if (decoder->packet.type == INTEL_PT_FUP) {
1380                decoder->fup_tx_flags = fup_tx_flags;
1381                decoder->set_fup_tx_flags = true;
1382                if (!(decoder->fup_tx_flags & INTEL_PT_ABORT_TX))
1383                        *no_tip = true;
1384        } else {
1385                intel_pt_log_at("ERROR: Missing FUP after MODE.TSX",
1386                                decoder->pos);
1387                intel_pt_update_in_tx(decoder);
1388        }
1389        return 0;
1390}
1391
1392static uint64_t intel_pt_8b_tsc(uint64_t timestamp, uint64_t ref_timestamp)
1393{
1394        timestamp |= (ref_timestamp & (0xffULL << 56));
1395
1396        if (timestamp < ref_timestamp) {
1397                if (ref_timestamp - timestamp > (1ULL << 55))
1398                        timestamp += (1ULL << 56);
1399        } else {
1400                if (timestamp - ref_timestamp > (1ULL << 55))
1401                        timestamp -= (1ULL << 56);
1402        }
1403
1404        return timestamp;
1405}
1406
1407static void intel_pt_calc_tsc_timestamp(struct intel_pt_decoder *decoder)
1408{
1409        uint64_t timestamp;
1410
1411        decoder->have_tma = false;
1412
1413        if (decoder->ref_timestamp) {
1414                timestamp = intel_pt_8b_tsc(decoder->packet.payload,
1415                                            decoder->ref_timestamp);
1416                decoder->tsc_timestamp = timestamp;
1417                decoder->timestamp = timestamp;
1418                decoder->ref_timestamp = 0;
1419                decoder->timestamp_insn_cnt = 0;
1420        } else if (decoder->timestamp) {
1421                timestamp = decoder->packet.payload |
1422                            (decoder->timestamp & (0xffULL << 56));
1423                decoder->tsc_timestamp = timestamp;
1424                if (timestamp < decoder->timestamp &&
1425                    decoder->timestamp - timestamp < decoder->tsc_slip) {
1426                        intel_pt_log_to("Suppressing backwards timestamp",
1427                                        timestamp);
1428                        timestamp = decoder->timestamp;
1429                }
1430                if (timestamp < decoder->timestamp) {
1431                        intel_pt_log_to("Wraparound timestamp", timestamp);
1432                        timestamp += (1ULL << 56);
1433                        decoder->tsc_timestamp = timestamp;
1434                }
1435                decoder->timestamp = timestamp;
1436                decoder->timestamp_insn_cnt = 0;
1437        }
1438
1439        if (decoder->last_packet_type == INTEL_PT_CYC) {
1440                decoder->cyc_ref_timestamp = decoder->timestamp;
1441                decoder->cycle_cnt = 0;
1442                decoder->have_calc_cyc_to_tsc = false;
1443                intel_pt_calc_cyc_to_tsc(decoder, false);
1444        }
1445
1446        intel_pt_log_to("Setting timestamp", decoder->timestamp);
1447}
1448
1449static int intel_pt_overflow(struct intel_pt_decoder *decoder)
1450{
1451        intel_pt_log("ERROR: Buffer overflow\n");
1452        intel_pt_clear_tx_flags(decoder);
1453        decoder->timestamp_insn_cnt = 0;
1454        decoder->pkt_state = INTEL_PT_STATE_ERR_RESYNC;
1455        decoder->overflow = true;
1456        return -EOVERFLOW;
1457}
1458
1459static inline void intel_pt_mtc_cyc_cnt_pge(struct intel_pt_decoder *decoder)
1460{
1461        if (decoder->have_cyc)
1462                return;
1463
1464        decoder->cyc_cnt_timestamp = decoder->timestamp;
1465        decoder->base_cyc_cnt = decoder->tot_cyc_cnt;
1466}
1467
1468static inline void intel_pt_mtc_cyc_cnt_cbr(struct intel_pt_decoder *decoder)
1469{
1470        decoder->tsc_to_cyc = decoder->cbr / decoder->max_non_turbo_ratio_fp;
1471
1472        if (decoder->pge)
1473                intel_pt_mtc_cyc_cnt_pge(decoder);
1474}
1475
1476static inline void intel_pt_mtc_cyc_cnt_upd(struct intel_pt_decoder *decoder)
1477{
1478        uint64_t tot_cyc_cnt, tsc_delta;
1479
1480        if (decoder->have_cyc)
1481                return;
1482
1483        decoder->sample_cyc = true;
1484
1485        if (!decoder->pge || decoder->timestamp <= decoder->cyc_cnt_timestamp)
1486                return;
1487
1488        tsc_delta = decoder->timestamp - decoder->cyc_cnt_timestamp;
1489        tot_cyc_cnt = tsc_delta * decoder->tsc_to_cyc + decoder->base_cyc_cnt;
1490
1491        if (tot_cyc_cnt > decoder->tot_cyc_cnt)
1492                decoder->tot_cyc_cnt = tot_cyc_cnt;
1493}
1494
1495static void intel_pt_calc_tma(struct intel_pt_decoder *decoder)
1496{
1497        uint32_t ctc = decoder->packet.payload;
1498        uint32_t fc = decoder->packet.count;
1499        uint32_t ctc_rem = ctc & decoder->ctc_rem_mask;
1500
1501        if (!decoder->tsc_ctc_ratio_d)
1502                return;
1503
1504        if (decoder->pge && !decoder->in_psb)
1505                intel_pt_mtc_cyc_cnt_pge(decoder);
1506        else
1507                intel_pt_mtc_cyc_cnt_upd(decoder);
1508
1509        decoder->last_mtc = (ctc >> decoder->mtc_shift) & 0xff;
1510        decoder->ctc_timestamp = decoder->tsc_timestamp - fc;
1511        if (decoder->tsc_ctc_mult) {
1512                decoder->ctc_timestamp -= ctc_rem * decoder->tsc_ctc_mult;
1513        } else {
1514                decoder->ctc_timestamp -= multdiv(ctc_rem,
1515                                                  decoder->tsc_ctc_ratio_n,
1516                                                  decoder->tsc_ctc_ratio_d);
1517        }
1518        decoder->ctc_delta = 0;
1519        decoder->have_tma = true;
1520        decoder->fixup_last_mtc = true;
1521        intel_pt_log("CTC timestamp " x64_fmt " last MTC %#x  CTC rem %#x\n",
1522                     decoder->ctc_timestamp, decoder->last_mtc, ctc_rem);
1523}
1524
1525static void intel_pt_calc_mtc_timestamp(struct intel_pt_decoder *decoder)
1526{
1527        uint64_t timestamp;
1528        uint32_t mtc, mtc_delta;
1529
1530        if (!decoder->have_tma)
1531                return;
1532
1533        mtc = decoder->packet.payload;
1534
1535        if (decoder->mtc_shift > 8 && decoder->fixup_last_mtc) {
1536                decoder->fixup_last_mtc = false;
1537                intel_pt_fixup_last_mtc(mtc, decoder->mtc_shift,
1538                                        &decoder->last_mtc);
1539        }
1540
1541        if (mtc > decoder->last_mtc)
1542                mtc_delta = mtc - decoder->last_mtc;
1543        else
1544                mtc_delta = mtc + 256 - decoder->last_mtc;
1545
1546        decoder->ctc_delta += mtc_delta << decoder->mtc_shift;
1547
1548        if (decoder->tsc_ctc_mult) {
1549                timestamp = decoder->ctc_timestamp +
1550                            decoder->ctc_delta * decoder->tsc_ctc_mult;
1551        } else {
1552                timestamp = decoder->ctc_timestamp +
1553                            multdiv(decoder->ctc_delta,
1554                                    decoder->tsc_ctc_ratio_n,
1555                                    decoder->tsc_ctc_ratio_d);
1556        }
1557
1558        if (timestamp < decoder->timestamp)
1559                intel_pt_log("Suppressing MTC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1560                             timestamp, decoder->timestamp);
1561        else
1562                decoder->timestamp = timestamp;
1563
1564        intel_pt_mtc_cyc_cnt_upd(decoder);
1565
1566        decoder->timestamp_insn_cnt = 0;
1567        decoder->last_mtc = mtc;
1568
1569        if (decoder->last_packet_type == INTEL_PT_CYC) {
1570                decoder->cyc_ref_timestamp = decoder->timestamp;
1571                decoder->cycle_cnt = 0;
1572                decoder->have_calc_cyc_to_tsc = false;
1573                intel_pt_calc_cyc_to_tsc(decoder, true);
1574        }
1575
1576        intel_pt_log_to("Setting timestamp", decoder->timestamp);
1577}
1578
1579static void intel_pt_calc_cbr(struct intel_pt_decoder *decoder)
1580{
1581        unsigned int cbr = decoder->packet.payload & 0xff;
1582
1583        decoder->cbr_payload = decoder->packet.payload;
1584
1585        if (decoder->cbr == cbr)
1586                return;
1587
1588        decoder->cbr = cbr;
1589        decoder->cbr_cyc_to_tsc = decoder->max_non_turbo_ratio_fp / cbr;
1590
1591        intel_pt_mtc_cyc_cnt_cbr(decoder);
1592}
1593
1594static void intel_pt_calc_cyc_timestamp(struct intel_pt_decoder *decoder)
1595{
1596        uint64_t timestamp = decoder->cyc_ref_timestamp;
1597
1598        decoder->have_cyc = true;
1599
1600        decoder->cycle_cnt += decoder->packet.payload;
1601        if (decoder->pge)
1602                decoder->tot_cyc_cnt += decoder->packet.payload;
1603        decoder->sample_cyc = true;
1604
1605        if (!decoder->cyc_ref_timestamp)
1606                return;
1607
1608        if (decoder->have_calc_cyc_to_tsc)
1609                timestamp += decoder->cycle_cnt * decoder->calc_cyc_to_tsc;
1610        else if (decoder->cbr)
1611                timestamp += decoder->cycle_cnt * decoder->cbr_cyc_to_tsc;
1612        else
1613                return;
1614
1615        if (timestamp < decoder->timestamp)
1616                intel_pt_log("Suppressing CYC timestamp " x64_fmt " less than current timestamp " x64_fmt "\n",
1617                             timestamp, decoder->timestamp);
1618        else
1619                decoder->timestamp = timestamp;
1620
1621        decoder->timestamp_insn_cnt = 0;
1622
1623        intel_pt_log_to("Setting timestamp", decoder->timestamp);
1624}
1625
1626static void intel_pt_bbp(struct intel_pt_decoder *decoder)
1627{
1628        if (decoder->prev_pkt_ctx == INTEL_PT_NO_CTX) {
1629                memset(decoder->state.items.mask, 0, sizeof(decoder->state.items.mask));
1630                decoder->state.items.is_32_bit = false;
1631        }
1632        decoder->blk_type = decoder->packet.payload;
1633        decoder->blk_type_pos = intel_pt_blk_type_pos(decoder->blk_type);
1634        if (decoder->blk_type == INTEL_PT_GP_REGS)
1635                decoder->state.items.is_32_bit = decoder->packet.count;
1636        if (decoder->blk_type_pos < 0) {
1637                intel_pt_log("WARNING: Unknown block type %u\n",
1638                             decoder->blk_type);
1639        } else if (decoder->state.items.mask[decoder->blk_type_pos]) {
1640                intel_pt_log("WARNING: Duplicate block type %u\n",
1641                             decoder->blk_type);
1642        }
1643}
1644
1645static void intel_pt_bip(struct intel_pt_decoder *decoder)
1646{
1647        uint32_t id = decoder->packet.count;
1648        uint32_t bit = 1 << id;
1649        int pos = decoder->blk_type_pos;
1650
1651        if (pos < 0 || id >= INTEL_PT_BLK_ITEM_ID_CNT) {
1652                intel_pt_log("WARNING: Unknown block item %u type %d\n",
1653                             id, decoder->blk_type);
1654                return;
1655        }
1656
1657        if (decoder->state.items.mask[pos] & bit) {
1658                intel_pt_log("WARNING: Duplicate block item %u type %d\n",
1659                             id, decoder->blk_type);
1660        }
1661
1662        decoder->state.items.mask[pos] |= bit;
1663        decoder->state.items.val[pos][id] = decoder->packet.payload;
1664}
1665
1666/* Walk PSB+ packets when already in sync. */
1667static int intel_pt_walk_psbend(struct intel_pt_decoder *decoder)
1668{
1669        int err;
1670
1671        decoder->in_psb = true;
1672
1673        while (1) {
1674                err = intel_pt_get_next_packet(decoder);
1675                if (err)
1676                        goto out;
1677
1678                switch (decoder->packet.type) {
1679                case INTEL_PT_PSBEND:
1680                        err = 0;
1681                        goto out;
1682
1683                case INTEL_PT_TIP_PGD:
1684                case INTEL_PT_TIP_PGE:
1685                case INTEL_PT_TIP:
1686                case INTEL_PT_TNT:
1687                case INTEL_PT_TRACESTOP:
1688                case INTEL_PT_BAD:
1689                case INTEL_PT_PSB:
1690                case INTEL_PT_PTWRITE:
1691                case INTEL_PT_PTWRITE_IP:
1692                case INTEL_PT_EXSTOP:
1693                case INTEL_PT_EXSTOP_IP:
1694                case INTEL_PT_MWAIT:
1695                case INTEL_PT_PWRE:
1696                case INTEL_PT_PWRX:
1697                case INTEL_PT_BBP:
1698                case INTEL_PT_BIP:
1699                case INTEL_PT_BEP:
1700                case INTEL_PT_BEP_IP:
1701                        decoder->have_tma = false;
1702                        intel_pt_log("ERROR: Unexpected packet\n");
1703                        err = -EAGAIN;
1704                        goto out;
1705
1706                case INTEL_PT_OVF:
1707                        err = intel_pt_overflow(decoder);
1708                        goto out;
1709
1710                case INTEL_PT_TSC:
1711                        intel_pt_calc_tsc_timestamp(decoder);
1712                        break;
1713
1714                case INTEL_PT_TMA:
1715                        intel_pt_calc_tma(decoder);
1716                        break;
1717
1718                case INTEL_PT_CBR:
1719                        intel_pt_calc_cbr(decoder);
1720                        break;
1721
1722                case INTEL_PT_MODE_EXEC:
1723                        decoder->exec_mode = decoder->packet.payload;
1724                        break;
1725
1726                case INTEL_PT_PIP:
1727                        decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1728                        break;
1729
1730                case INTEL_PT_FUP:
1731                        decoder->pge = true;
1732                        if (decoder->packet.count)
1733                                intel_pt_set_last_ip(decoder);
1734                        break;
1735
1736                case INTEL_PT_MODE_TSX:
1737                        intel_pt_update_in_tx(decoder);
1738                        break;
1739
1740                case INTEL_PT_MTC:
1741                        intel_pt_calc_mtc_timestamp(decoder);
1742                        if (decoder->period_type == INTEL_PT_PERIOD_MTC)
1743                                decoder->state.type |= INTEL_PT_INSTRUCTION;
1744                        break;
1745
1746                case INTEL_PT_CYC:
1747                case INTEL_PT_VMCS:
1748                case INTEL_PT_MNT:
1749                case INTEL_PT_PAD:
1750                default:
1751                        break;
1752                }
1753        }
1754out:
1755        decoder->in_psb = false;
1756
1757        return err;
1758}
1759
1760static int intel_pt_walk_fup_tip(struct intel_pt_decoder *decoder)
1761{
1762        int err;
1763
1764        if (decoder->tx_flags & INTEL_PT_ABORT_TX) {
1765                decoder->tx_flags = 0;
1766                decoder->state.flags &= ~INTEL_PT_IN_TX;
1767                decoder->state.flags |= INTEL_PT_ABORT_TX;
1768        } else {
1769                decoder->state.flags |= INTEL_PT_ASYNC;
1770        }
1771
1772        while (1) {
1773                err = intel_pt_get_next_packet(decoder);
1774                if (err)
1775                        return err;
1776
1777                switch (decoder->packet.type) {
1778                case INTEL_PT_TNT:
1779                case INTEL_PT_FUP:
1780                case INTEL_PT_TRACESTOP:
1781                case INTEL_PT_PSB:
1782                case INTEL_PT_TSC:
1783                case INTEL_PT_TMA:
1784                case INTEL_PT_MODE_TSX:
1785                case INTEL_PT_BAD:
1786                case INTEL_PT_PSBEND:
1787                case INTEL_PT_PTWRITE:
1788                case INTEL_PT_PTWRITE_IP:
1789                case INTEL_PT_EXSTOP:
1790                case INTEL_PT_EXSTOP_IP:
1791                case INTEL_PT_MWAIT:
1792                case INTEL_PT_PWRE:
1793                case INTEL_PT_PWRX:
1794                case INTEL_PT_BBP:
1795                case INTEL_PT_BIP:
1796                case INTEL_PT_BEP:
1797                case INTEL_PT_BEP_IP:
1798                        intel_pt_log("ERROR: Missing TIP after FUP\n");
1799                        decoder->pkt_state = INTEL_PT_STATE_ERR3;
1800                        decoder->pkt_step = 0;
1801                        return -ENOENT;
1802
1803                case INTEL_PT_CBR:
1804                        intel_pt_calc_cbr(decoder);
1805                        break;
1806
1807                case INTEL_PT_OVF:
1808                        return intel_pt_overflow(decoder);
1809
1810                case INTEL_PT_TIP_PGD:
1811                        decoder->state.from_ip = decoder->ip;
1812                        if (decoder->packet.count == 0) {
1813                                decoder->state.to_ip = 0;
1814                        } else {
1815                                intel_pt_set_ip(decoder);
1816                                decoder->state.to_ip = decoder->ip;
1817                        }
1818                        decoder->pge = false;
1819                        decoder->continuous_period = false;
1820                        decoder->state.type |= INTEL_PT_TRACE_END;
1821                        return 0;
1822
1823                case INTEL_PT_TIP_PGE:
1824                        decoder->pge = true;
1825                        intel_pt_log("Omitting PGE ip " x64_fmt "\n",
1826                                     decoder->ip);
1827                        decoder->state.from_ip = 0;
1828                        if (decoder->packet.count == 0) {
1829                                decoder->state.to_ip = 0;
1830                        } else {
1831                                intel_pt_set_ip(decoder);
1832                                decoder->state.to_ip = decoder->ip;
1833                        }
1834                        decoder->state.type |= INTEL_PT_TRACE_BEGIN;
1835                        intel_pt_mtc_cyc_cnt_pge(decoder);
1836                        return 0;
1837
1838                case INTEL_PT_TIP:
1839                        decoder->state.from_ip = decoder->ip;
1840                        if (decoder->packet.count == 0) {
1841                                decoder->state.to_ip = 0;
1842                        } else {
1843                                intel_pt_set_ip(decoder);
1844                                decoder->state.to_ip = decoder->ip;
1845                        }
1846                        return 0;
1847
1848                case INTEL_PT_PIP:
1849                        decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1850                        break;
1851
1852                case INTEL_PT_MTC:
1853                        intel_pt_calc_mtc_timestamp(decoder);
1854                        if (decoder->period_type == INTEL_PT_PERIOD_MTC)
1855                                decoder->state.type |= INTEL_PT_INSTRUCTION;
1856                        break;
1857
1858                case INTEL_PT_CYC:
1859                        intel_pt_calc_cyc_timestamp(decoder);
1860                        break;
1861
1862                case INTEL_PT_MODE_EXEC:
1863                        decoder->exec_mode = decoder->packet.payload;
1864                        break;
1865
1866                case INTEL_PT_VMCS:
1867                case INTEL_PT_MNT:
1868                case INTEL_PT_PAD:
1869                        break;
1870
1871                default:
1872                        return intel_pt_bug(decoder);
1873                }
1874        }
1875}
1876
1877static int intel_pt_walk_trace(struct intel_pt_decoder *decoder)
1878{
1879        bool no_tip = false;
1880        int err;
1881
1882        while (1) {
1883                err = intel_pt_get_next_packet(decoder);
1884                if (err)
1885                        return err;
1886next:
1887                switch (decoder->packet.type) {
1888                case INTEL_PT_TNT:
1889                        if (!decoder->packet.count)
1890                                break;
1891                        decoder->tnt = decoder->packet;
1892                        decoder->pkt_state = INTEL_PT_STATE_TNT;
1893                        err = intel_pt_walk_tnt(decoder);
1894                        if (err == -EAGAIN)
1895                                break;
1896                        return err;
1897
1898                case INTEL_PT_TIP_PGD:
1899                        if (decoder->packet.count != 0)
1900                                intel_pt_set_last_ip(decoder);
1901                        decoder->pkt_state = INTEL_PT_STATE_TIP_PGD;
1902                        return intel_pt_walk_tip(decoder);
1903
1904                case INTEL_PT_TIP_PGE: {
1905                        decoder->pge = true;
1906                        intel_pt_mtc_cyc_cnt_pge(decoder);
1907                        if (decoder->packet.count == 0) {
1908                                intel_pt_log_at("Skipping zero TIP.PGE",
1909                                                decoder->pos);
1910                                break;
1911                        }
1912                        intel_pt_set_ip(decoder);
1913                        decoder->state.from_ip = 0;
1914                        decoder->state.to_ip = decoder->ip;
1915                        decoder->state.type |= INTEL_PT_TRACE_BEGIN;
1916                        return 0;
1917                }
1918
1919                case INTEL_PT_OVF:
1920                        return intel_pt_overflow(decoder);
1921
1922                case INTEL_PT_TIP:
1923                        if (decoder->packet.count != 0)
1924                                intel_pt_set_last_ip(decoder);
1925                        decoder->pkt_state = INTEL_PT_STATE_TIP;
1926                        return intel_pt_walk_tip(decoder);
1927
1928                case INTEL_PT_FUP:
1929                        if (decoder->packet.count == 0) {
1930                                intel_pt_log_at("Skipping zero FUP",
1931                                                decoder->pos);
1932                                no_tip = false;
1933                                break;
1934                        }
1935                        intel_pt_set_last_ip(decoder);
1936                        if (!decoder->branch_enable) {
1937                                decoder->ip = decoder->last_ip;
1938                                if (intel_pt_fup_event(decoder))
1939                                        return 0;
1940                                no_tip = false;
1941                                break;
1942                        }
1943                        if (decoder->set_fup_mwait)
1944                                no_tip = true;
1945                        err = intel_pt_walk_fup(decoder);
1946                        if (err != -EAGAIN) {
1947                                if (err)
1948                                        return err;
1949                                if (no_tip)
1950                                        decoder->pkt_state =
1951                                                INTEL_PT_STATE_FUP_NO_TIP;
1952                                else
1953                                        decoder->pkt_state = INTEL_PT_STATE_FUP;
1954                                return 0;
1955                        }
1956                        if (no_tip) {
1957                                no_tip = false;
1958                                break;
1959                        }
1960                        return intel_pt_walk_fup_tip(decoder);
1961
1962                case INTEL_PT_TRACESTOP:
1963                        decoder->pge = false;
1964                        decoder->continuous_period = false;
1965                        intel_pt_clear_tx_flags(decoder);
1966                        decoder->have_tma = false;
1967                        break;
1968
1969                case INTEL_PT_PSB:
1970                        decoder->last_ip = 0;
1971                        decoder->have_last_ip = true;
1972                        intel_pt_clear_stack(&decoder->stack);
1973                        err = intel_pt_walk_psbend(decoder);
1974                        if (err == -EAGAIN)
1975                                goto next;
1976                        if (err)
1977                                return err;
1978                        /*
1979                         * PSB+ CBR will not have changed but cater for the
1980                         * possibility of another CBR change that gets caught up
1981                         * in the PSB+.
1982                         */
1983                        if (decoder->cbr != decoder->cbr_seen)
1984                                return 0;
1985                        break;
1986
1987                case INTEL_PT_PIP:
1988                        decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
1989                        break;
1990
1991                case INTEL_PT_MTC:
1992                        intel_pt_calc_mtc_timestamp(decoder);
1993                        if (decoder->period_type != INTEL_PT_PERIOD_MTC)
1994                                break;
1995                        /*
1996                         * Ensure that there has been an instruction since the
1997                         * last MTC.
1998                         */
1999                        if (!decoder->mtc_insn)
2000                                break;
2001                        decoder->mtc_insn = false;
2002                        /* Ensure that there is a timestamp */
2003                        if (!decoder->timestamp)
2004                                break;
2005                        decoder->state.type = INTEL_PT_INSTRUCTION;
2006                        decoder->state.from_ip = decoder->ip;
2007                        decoder->state.to_ip = 0;
2008                        decoder->mtc_insn = false;
2009                        return 0;
2010
2011                case INTEL_PT_TSC:
2012                        intel_pt_calc_tsc_timestamp(decoder);
2013                        break;
2014
2015                case INTEL_PT_TMA:
2016                        intel_pt_calc_tma(decoder);
2017                        break;
2018
2019                case INTEL_PT_CYC:
2020                        intel_pt_calc_cyc_timestamp(decoder);
2021                        break;
2022
2023                case INTEL_PT_CBR:
2024                        intel_pt_calc_cbr(decoder);
2025                        if (decoder->cbr != decoder->cbr_seen)
2026                                return 0;
2027                        break;
2028
2029                case INTEL_PT_MODE_EXEC:
2030                        decoder->exec_mode = decoder->packet.payload;
2031                        break;
2032
2033                case INTEL_PT_MODE_TSX:
2034                        /* MODE_TSX need not be followed by FUP */
2035                        if (!decoder->pge) {
2036                                intel_pt_update_in_tx(decoder);
2037                                break;
2038                        }
2039                        err = intel_pt_mode_tsx(decoder, &no_tip);
2040                        if (err)
2041                                return err;
2042                        goto next;
2043
2044                case INTEL_PT_BAD: /* Does not happen */
2045                        return intel_pt_bug(decoder);
2046
2047                case INTEL_PT_PSBEND:
2048                case INTEL_PT_VMCS:
2049                case INTEL_PT_MNT:
2050                case INTEL_PT_PAD:
2051                        break;
2052
2053                case INTEL_PT_PTWRITE_IP:
2054                        decoder->fup_ptw_payload = decoder->packet.payload;
2055                        err = intel_pt_get_next_packet(decoder);
2056                        if (err)
2057                                return err;
2058                        if (decoder->packet.type == INTEL_PT_FUP) {
2059                                decoder->set_fup_ptw = true;
2060                                no_tip = true;
2061                        } else {
2062                                intel_pt_log_at("ERROR: Missing FUP after PTWRITE",
2063                                                decoder->pos);
2064                        }
2065                        goto next;
2066
2067                case INTEL_PT_PTWRITE:
2068                        decoder->state.type = INTEL_PT_PTW;
2069                        decoder->state.from_ip = decoder->ip;
2070                        decoder->state.to_ip = 0;
2071                        decoder->state.ptw_payload = decoder->packet.payload;
2072                        return 0;
2073
2074                case INTEL_PT_MWAIT:
2075                        decoder->fup_mwait_payload = decoder->packet.payload;
2076                        decoder->set_fup_mwait = true;
2077                        break;
2078
2079                case INTEL_PT_PWRE:
2080                        if (decoder->set_fup_mwait) {
2081                                decoder->fup_pwre_payload =
2082                                                        decoder->packet.payload;
2083                                decoder->set_fup_pwre = true;
2084                                break;
2085                        }
2086                        decoder->state.type = INTEL_PT_PWR_ENTRY;
2087                        decoder->state.from_ip = decoder->ip;
2088                        decoder->state.to_ip = 0;
2089                        decoder->state.pwrx_payload = decoder->packet.payload;
2090                        return 0;
2091
2092                case INTEL_PT_EXSTOP_IP:
2093                        err = intel_pt_get_next_packet(decoder);
2094                        if (err)
2095                                return err;
2096                        if (decoder->packet.type == INTEL_PT_FUP) {
2097                                decoder->set_fup_exstop = true;
2098                                no_tip = true;
2099                        } else {
2100                                intel_pt_log_at("ERROR: Missing FUP after EXSTOP",
2101                                                decoder->pos);
2102                        }
2103                        goto next;
2104
2105                case INTEL_PT_EXSTOP:
2106                        decoder->state.type = INTEL_PT_EX_STOP;
2107                        decoder->state.from_ip = decoder->ip;
2108                        decoder->state.to_ip = 0;
2109                        return 0;
2110
2111                case INTEL_PT_PWRX:
2112                        decoder->state.type = INTEL_PT_PWR_EXIT;
2113                        decoder->state.from_ip = decoder->ip;
2114                        decoder->state.to_ip = 0;
2115                        decoder->state.pwrx_payload = decoder->packet.payload;
2116                        return 0;
2117
2118                case INTEL_PT_BBP:
2119                        intel_pt_bbp(decoder);
2120                        break;
2121
2122                case INTEL_PT_BIP:
2123                        intel_pt_bip(decoder);
2124                        break;
2125
2126                case INTEL_PT_BEP:
2127                        decoder->state.type = INTEL_PT_BLK_ITEMS;
2128                        decoder->state.from_ip = decoder->ip;
2129                        decoder->state.to_ip = 0;
2130                        return 0;
2131
2132                case INTEL_PT_BEP_IP:
2133                        err = intel_pt_get_next_packet(decoder);
2134                        if (err)
2135                                return err;
2136                        if (decoder->packet.type == INTEL_PT_FUP) {
2137                                decoder->set_fup_bep = true;
2138                                no_tip = true;
2139                        } else {
2140                                intel_pt_log_at("ERROR: Missing FUP after BEP",
2141                                                decoder->pos);
2142                        }
2143                        goto next;
2144
2145                default:
2146                        return intel_pt_bug(decoder);
2147                }
2148        }
2149}
2150
2151static inline bool intel_pt_have_ip(struct intel_pt_decoder *decoder)
2152{
2153        return decoder->packet.count &&
2154               (decoder->have_last_ip || decoder->packet.count == 3 ||
2155                decoder->packet.count == 6);
2156}
2157
2158/* Walk PSB+ packets to get in sync. */
2159static int intel_pt_walk_psb(struct intel_pt_decoder *decoder)
2160{
2161        int err;
2162
2163        decoder->in_psb = true;
2164
2165        while (1) {
2166                err = intel_pt_get_next_packet(decoder);
2167                if (err)
2168                        goto out;
2169
2170                switch (decoder->packet.type) {
2171                case INTEL_PT_TIP_PGD:
2172                        decoder->continuous_period = false;
2173                        __fallthrough;
2174                case INTEL_PT_TIP_PGE:
2175                case INTEL_PT_TIP:
2176                case INTEL_PT_PTWRITE:
2177                case INTEL_PT_PTWRITE_IP:
2178                case INTEL_PT_EXSTOP:
2179                case INTEL_PT_EXSTOP_IP:
2180                case INTEL_PT_MWAIT:
2181                case INTEL_PT_PWRE:
2182                case INTEL_PT_PWRX:
2183                case INTEL_PT_BBP:
2184                case INTEL_PT_BIP:
2185                case INTEL_PT_BEP:
2186                case INTEL_PT_BEP_IP:
2187                        intel_pt_log("ERROR: Unexpected packet\n");
2188                        err = -ENOENT;
2189                        goto out;
2190
2191                case INTEL_PT_FUP:
2192                        decoder->pge = true;
2193                        if (intel_pt_have_ip(decoder)) {
2194                                uint64_t current_ip = decoder->ip;
2195
2196                                intel_pt_set_ip(decoder);
2197                                if (current_ip)
2198                                        intel_pt_log_to("Setting IP",
2199                                                        decoder->ip);
2200                        }
2201                        break;
2202
2203                case INTEL_PT_MTC:
2204                        intel_pt_calc_mtc_timestamp(decoder);
2205                        break;
2206
2207                case INTEL_PT_TSC:
2208                        intel_pt_calc_tsc_timestamp(decoder);
2209                        break;
2210
2211                case INTEL_PT_TMA:
2212                        intel_pt_calc_tma(decoder);
2213                        break;
2214
2215                case INTEL_PT_CYC:
2216                        intel_pt_calc_cyc_timestamp(decoder);
2217                        break;
2218
2219                case INTEL_PT_CBR:
2220                        intel_pt_calc_cbr(decoder);
2221                        break;
2222
2223                case INTEL_PT_PIP:
2224                        decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
2225                        break;
2226
2227                case INTEL_PT_MODE_EXEC:
2228                        decoder->exec_mode = decoder->packet.payload;
2229                        break;
2230
2231                case INTEL_PT_MODE_TSX:
2232                        intel_pt_update_in_tx(decoder);
2233                        break;
2234
2235                case INTEL_PT_TRACESTOP:
2236                        decoder->pge = false;
2237                        decoder->continuous_period = false;
2238                        intel_pt_clear_tx_flags(decoder);
2239                        __fallthrough;
2240
2241                case INTEL_PT_TNT:
2242                        decoder->have_tma = false;
2243                        intel_pt_log("ERROR: Unexpected packet\n");
2244                        if (decoder->ip)
2245                                decoder->pkt_state = INTEL_PT_STATE_ERR4;
2246                        else
2247                                decoder->pkt_state = INTEL_PT_STATE_ERR3;
2248                        err = -ENOENT;
2249                        goto out;
2250
2251                case INTEL_PT_BAD: /* Does not happen */
2252                        err = intel_pt_bug(decoder);
2253                        goto out;
2254
2255                case INTEL_PT_OVF:
2256                        err = intel_pt_overflow(decoder);
2257                        goto out;
2258
2259                case INTEL_PT_PSBEND:
2260                        err = 0;
2261                        goto out;
2262
2263                case INTEL_PT_PSB:
2264                case INTEL_PT_VMCS:
2265                case INTEL_PT_MNT:
2266                case INTEL_PT_PAD:
2267                default:
2268                        break;
2269                }
2270        }
2271out:
2272        decoder->in_psb = false;
2273
2274        return err;
2275}
2276
2277static int intel_pt_walk_to_ip(struct intel_pt_decoder *decoder)
2278{
2279        int err;
2280
2281        while (1) {
2282                err = intel_pt_get_next_packet(decoder);
2283                if (err)
2284                        return err;
2285
2286                switch (decoder->packet.type) {
2287                case INTEL_PT_TIP_PGD:
2288                        decoder->continuous_period = false;
2289                        decoder->pge = false;
2290                        if (intel_pt_have_ip(decoder))
2291                                intel_pt_set_ip(decoder);
2292                        if (!decoder->ip)
2293                                break;
2294                        decoder->state.type |= INTEL_PT_TRACE_END;
2295                        return 0;
2296
2297                case INTEL_PT_TIP_PGE:
2298                        decoder->pge = true;
2299                        intel_pt_mtc_cyc_cnt_pge(decoder);
2300                        if (intel_pt_have_ip(decoder))
2301                                intel_pt_set_ip(decoder);
2302                        if (!decoder->ip)
2303                                break;
2304                        decoder->state.type |= INTEL_PT_TRACE_BEGIN;
2305                        return 0;
2306
2307                case INTEL_PT_TIP:
2308                        decoder->pge = true;
2309                        if (intel_pt_have_ip(decoder))
2310                                intel_pt_set_ip(decoder);
2311                        if (!decoder->ip)
2312                                break;
2313                        return 0;
2314
2315                case INTEL_PT_FUP:
2316                        if (intel_pt_have_ip(decoder))
2317                                intel_pt_set_ip(decoder);
2318                        if (decoder->ip)
2319                                return 0;
2320                        break;
2321
2322                case INTEL_PT_MTC:
2323                        intel_pt_calc_mtc_timestamp(decoder);
2324                        break;
2325
2326                case INTEL_PT_TSC:
2327                        intel_pt_calc_tsc_timestamp(decoder);
2328                        break;
2329
2330                case INTEL_PT_TMA:
2331                        intel_pt_calc_tma(decoder);
2332                        break;
2333
2334                case INTEL_PT_CYC:
2335                        intel_pt_calc_cyc_timestamp(decoder);
2336                        break;
2337
2338                case INTEL_PT_CBR:
2339                        intel_pt_calc_cbr(decoder);
2340                        break;
2341
2342                case INTEL_PT_PIP:
2343                        decoder->cr3 = decoder->packet.payload & (BIT63 - 1);
2344                        break;
2345
2346                case INTEL_PT_MODE_EXEC:
2347                        decoder->exec_mode = decoder->packet.payload;
2348                        break;
2349
2350                case INTEL_PT_MODE_TSX:
2351                        intel_pt_update_in_tx(decoder);
2352                        break;
2353
2354                case INTEL_PT_OVF:
2355                        return intel_pt_overflow(decoder);
2356
2357                case INTEL_PT_BAD: /* Does not happen */
2358                        return intel_pt_bug(decoder);
2359
2360                case INTEL_PT_TRACESTOP:
2361                        decoder->pge = false;
2362                        decoder->continuous_period = false;
2363                        intel_pt_clear_tx_flags(decoder);
2364                        decoder->have_tma = false;
2365                        break;
2366
2367                case INTEL_PT_PSB:
2368                        decoder->last_ip = 0;
2369                        decoder->have_last_ip = true;
2370                        intel_pt_clear_stack(&decoder->stack);
2371                        err = intel_pt_walk_psb(decoder);
2372                        if (err)
2373                                return err;
2374                        if (decoder->ip) {
2375                                /* Do not have a sample */
2376                                decoder->state.type = 0;
2377                                return 0;
2378                        }
2379                        break;
2380
2381                case INTEL_PT_TNT:
2382                case INTEL_PT_PSBEND:
2383                case INTEL_PT_VMCS:
2384                case INTEL_PT_MNT:
2385                case INTEL_PT_PAD:
2386                case INTEL_PT_PTWRITE:
2387                case INTEL_PT_PTWRITE_IP:
2388                case INTEL_PT_EXSTOP:
2389                case INTEL_PT_EXSTOP_IP:
2390                case INTEL_PT_MWAIT:
2391                case INTEL_PT_PWRE:
2392                case INTEL_PT_PWRX:
2393                case INTEL_PT_BBP:
2394                case INTEL_PT_BIP:
2395                case INTEL_PT_BEP:
2396                case INTEL_PT_BEP_IP:
2397                default:
2398                        break;
2399                }
2400        }
2401}
2402
2403static int intel_pt_sync_ip(struct intel_pt_decoder *decoder)
2404{
2405        int err;
2406
2407        decoder->set_fup_tx_flags = false;
2408        decoder->set_fup_ptw = false;
2409        decoder->set_fup_mwait = false;
2410        decoder->set_fup_pwre = false;
2411        decoder->set_fup_exstop = false;
2412        decoder->set_fup_bep = false;
2413
2414        if (!decoder->branch_enable) {
2415                decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2416                decoder->overflow = false;
2417                decoder->state.type = 0; /* Do not have a sample */
2418                return 0;
2419        }
2420
2421        intel_pt_log("Scanning for full IP\n");
2422        err = intel_pt_walk_to_ip(decoder);
2423        if (err)
2424                return err;
2425
2426        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2427        decoder->overflow = false;
2428
2429        decoder->state.from_ip = 0;
2430        decoder->state.to_ip = decoder->ip;
2431        intel_pt_log_to("Setting IP", decoder->ip);
2432
2433        return 0;
2434}
2435
2436static int intel_pt_part_psb(struct intel_pt_decoder *decoder)
2437{
2438        const unsigned char *end = decoder->buf + decoder->len;
2439        size_t i;
2440
2441        for (i = INTEL_PT_PSB_LEN - 1; i; i--) {
2442                if (i > decoder->len)
2443                        continue;
2444                if (!memcmp(end - i, INTEL_PT_PSB_STR, i))
2445                        return i;
2446        }
2447        return 0;
2448}
2449
2450static int intel_pt_rest_psb(struct intel_pt_decoder *decoder, int part_psb)
2451{
2452        size_t rest_psb = INTEL_PT_PSB_LEN - part_psb;
2453        const char *psb = INTEL_PT_PSB_STR;
2454
2455        if (rest_psb > decoder->len ||
2456            memcmp(decoder->buf, psb + part_psb, rest_psb))
2457                return 0;
2458
2459        return rest_psb;
2460}
2461
2462static int intel_pt_get_split_psb(struct intel_pt_decoder *decoder,
2463                                  int part_psb)
2464{
2465        int rest_psb, ret;
2466
2467        decoder->pos += decoder->len;
2468        decoder->len = 0;
2469
2470        ret = intel_pt_get_next_data(decoder, false);
2471        if (ret)
2472                return ret;
2473
2474        rest_psb = intel_pt_rest_psb(decoder, part_psb);
2475        if (!rest_psb)
2476                return 0;
2477
2478        decoder->pos -= part_psb;
2479        decoder->next_buf = decoder->buf + rest_psb;
2480        decoder->next_len = decoder->len - rest_psb;
2481        memcpy(decoder->temp_buf, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2482        decoder->buf = decoder->temp_buf;
2483        decoder->len = INTEL_PT_PSB_LEN;
2484
2485        return 0;
2486}
2487
2488static int intel_pt_scan_for_psb(struct intel_pt_decoder *decoder)
2489{
2490        unsigned char *next;
2491        int ret;
2492
2493        intel_pt_log("Scanning for PSB\n");
2494        while (1) {
2495                if (!decoder->len) {
2496                        ret = intel_pt_get_next_data(decoder, false);
2497                        if (ret)
2498                                return ret;
2499                }
2500
2501                next = memmem(decoder->buf, decoder->len, INTEL_PT_PSB_STR,
2502                              INTEL_PT_PSB_LEN);
2503                if (!next) {
2504                        int part_psb;
2505
2506                        part_psb = intel_pt_part_psb(decoder);
2507                        if (part_psb) {
2508                                ret = intel_pt_get_split_psb(decoder, part_psb);
2509                                if (ret)
2510                                        return ret;
2511                        } else {
2512                                decoder->pos += decoder->len;
2513                                decoder->len = 0;
2514                        }
2515                        continue;
2516                }
2517
2518                decoder->pkt_step = next - decoder->buf;
2519                return intel_pt_get_next_packet(decoder);
2520        }
2521}
2522
2523static int intel_pt_sync(struct intel_pt_decoder *decoder)
2524{
2525        int err;
2526
2527        decoder->pge = false;
2528        decoder->continuous_period = false;
2529        decoder->have_last_ip = false;
2530        decoder->last_ip = 0;
2531        decoder->ip = 0;
2532        intel_pt_clear_stack(&decoder->stack);
2533
2534        err = intel_pt_scan_for_psb(decoder);
2535        if (err)
2536                return err;
2537
2538        decoder->have_last_ip = true;
2539        decoder->pkt_state = INTEL_PT_STATE_NO_IP;
2540
2541        err = intel_pt_walk_psb(decoder);
2542        if (err)
2543                return err;
2544
2545        if (decoder->ip) {
2546                decoder->state.type = 0; /* Do not have a sample */
2547                decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2548        } else {
2549                return intel_pt_sync_ip(decoder);
2550        }
2551
2552        return 0;
2553}
2554
2555static uint64_t intel_pt_est_timestamp(struct intel_pt_decoder *decoder)
2556{
2557        uint64_t est = decoder->sample_insn_cnt << 1;
2558
2559        if (!decoder->cbr || !decoder->max_non_turbo_ratio)
2560                goto out;
2561
2562        est *= decoder->max_non_turbo_ratio;
2563        est /= decoder->cbr;
2564out:
2565        return decoder->sample_timestamp + est;
2566}
2567
2568const struct intel_pt_state *intel_pt_decode(struct intel_pt_decoder *decoder)
2569{
2570        int err;
2571
2572        do {
2573                decoder->state.type = INTEL_PT_BRANCH;
2574                decoder->state.flags = 0;
2575
2576                switch (decoder->pkt_state) {
2577                case INTEL_PT_STATE_NO_PSB:
2578                        err = intel_pt_sync(decoder);
2579                        break;
2580                case INTEL_PT_STATE_NO_IP:
2581                        decoder->have_last_ip = false;
2582                        decoder->last_ip = 0;
2583                        decoder->ip = 0;
2584                        __fallthrough;
2585                case INTEL_PT_STATE_ERR_RESYNC:
2586                        err = intel_pt_sync_ip(decoder);
2587                        break;
2588                case INTEL_PT_STATE_IN_SYNC:
2589                        err = intel_pt_walk_trace(decoder);
2590                        break;
2591                case INTEL_PT_STATE_TNT:
2592                case INTEL_PT_STATE_TNT_CONT:
2593                        err = intel_pt_walk_tnt(decoder);
2594                        if (err == -EAGAIN)
2595                                err = intel_pt_walk_trace(decoder);
2596                        break;
2597                case INTEL_PT_STATE_TIP:
2598                case INTEL_PT_STATE_TIP_PGD:
2599                        err = intel_pt_walk_tip(decoder);
2600                        break;
2601                case INTEL_PT_STATE_FUP:
2602                        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2603                        err = intel_pt_walk_fup(decoder);
2604                        if (err == -EAGAIN)
2605                                err = intel_pt_walk_fup_tip(decoder);
2606                        else if (!err)
2607                                decoder->pkt_state = INTEL_PT_STATE_FUP;
2608                        break;
2609                case INTEL_PT_STATE_FUP_NO_TIP:
2610                        decoder->pkt_state = INTEL_PT_STATE_IN_SYNC;
2611                        err = intel_pt_walk_fup(decoder);
2612                        if (err == -EAGAIN)
2613                                err = intel_pt_walk_trace(decoder);
2614                        break;
2615                default:
2616                        err = intel_pt_bug(decoder);
2617                        break;
2618                }
2619        } while (err == -ENOLINK);
2620
2621        if (err) {
2622                decoder->state.err = intel_pt_ext_err(err);
2623                decoder->state.from_ip = decoder->ip;
2624                intel_pt_update_sample_time(decoder);
2625                decoder->sample_tot_cyc_cnt = decoder->tot_cyc_cnt;
2626        } else {
2627                decoder->state.err = 0;
2628                if (decoder->cbr != decoder->cbr_seen) {
2629                        decoder->cbr_seen = decoder->cbr;
2630                        if (!decoder->state.type) {
2631                                decoder->state.from_ip = decoder->ip;
2632                                decoder->state.to_ip = 0;
2633                        }
2634                        decoder->state.type |= INTEL_PT_CBR_CHG;
2635                        decoder->state.cbr_payload = decoder->cbr_payload;
2636                        decoder->state.cbr = decoder->cbr;
2637                }
2638                if (intel_pt_sample_time(decoder->pkt_state)) {
2639                        intel_pt_update_sample_time(decoder);
2640                        if (decoder->sample_cyc)
2641                                decoder->sample_tot_cyc_cnt = decoder->tot_cyc_cnt;
2642                }
2643        }
2644
2645        decoder->state.timestamp = decoder->sample_timestamp;
2646        decoder->state.est_timestamp = intel_pt_est_timestamp(decoder);
2647        decoder->state.cr3 = decoder->cr3;
2648        decoder->state.tot_insn_cnt = decoder->tot_insn_cnt;
2649        decoder->state.tot_cyc_cnt = decoder->sample_tot_cyc_cnt;
2650
2651        return &decoder->state;
2652}
2653
2654/**
2655 * intel_pt_next_psb - move buffer pointer to the start of the next PSB packet.
2656 * @buf: pointer to buffer pointer
2657 * @len: size of buffer
2658 *
2659 * Updates the buffer pointer to point to the start of the next PSB packet if
2660 * there is one, otherwise the buffer pointer is unchanged.  If @buf is updated,
2661 * @len is adjusted accordingly.
2662 *
2663 * Return: %true if a PSB packet is found, %false otherwise.
2664 */
2665static bool intel_pt_next_psb(unsigned char **buf, size_t *len)
2666{
2667        unsigned char *next;
2668
2669        next = memmem(*buf, *len, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2670        if (next) {
2671                *len -= next - *buf;
2672                *buf = next;
2673                return true;
2674        }
2675        return false;
2676}
2677
2678/**
2679 * intel_pt_step_psb - move buffer pointer to the start of the following PSB
2680 *                     packet.
2681 * @buf: pointer to buffer pointer
2682 * @len: size of buffer
2683 *
2684 * Updates the buffer pointer to point to the start of the following PSB packet
2685 * (skipping the PSB at @buf itself) if there is one, otherwise the buffer
2686 * pointer is unchanged.  If @buf is updated, @len is adjusted accordingly.
2687 *
2688 * Return: %true if a PSB packet is found, %false otherwise.
2689 */
2690static bool intel_pt_step_psb(unsigned char **buf, size_t *len)
2691{
2692        unsigned char *next;
2693
2694        if (!*len)
2695                return false;
2696
2697        next = memmem(*buf + 1, *len - 1, INTEL_PT_PSB_STR, INTEL_PT_PSB_LEN);
2698        if (next) {
2699                *len -= next - *buf;
2700                *buf = next;
2701                return true;
2702        }
2703        return false;
2704}
2705
2706/**
2707 * intel_pt_last_psb - find the last PSB packet in a buffer.
2708 * @buf: buffer
2709 * @len: size of buffer
2710 *
2711 * This function finds the last PSB in a buffer.
2712 *
2713 * Return: A pointer to the last PSB in @buf if found, %NULL otherwise.
2714 */
2715static unsigned char *intel_pt_last_psb(unsigned char *buf, size_t len)
2716{
2717        const char *n = INTEL_PT_PSB_STR;
2718        unsigned char *p;
2719        size_t k;
2720
2721        if (len < INTEL_PT_PSB_LEN)
2722                return NULL;
2723
2724        k = len - INTEL_PT_PSB_LEN + 1;
2725        while (1) {
2726                p = memrchr(buf, n[0], k);
2727                if (!p)
2728                        return NULL;
2729                if (!memcmp(p + 1, n + 1, INTEL_PT_PSB_LEN - 1))
2730                        return p;
2731                k = p - buf;
2732                if (!k)
2733                        return NULL;
2734        }
2735}
2736
2737/**
2738 * intel_pt_next_tsc - find and return next TSC.
2739 * @buf: buffer
2740 * @len: size of buffer
2741 * @tsc: TSC value returned
2742 * @rem: returns remaining size when TSC is found
2743 *
2744 * Find a TSC packet in @buf and return the TSC value.  This function assumes
2745 * that @buf starts at a PSB and that PSB+ will contain TSC and so stops if a
2746 * PSBEND packet is found.
2747 *
2748 * Return: %true if TSC is found, false otherwise.
2749 */
2750static bool intel_pt_next_tsc(unsigned char *buf, size_t len, uint64_t *tsc,
2751                              size_t *rem)
2752{
2753        enum intel_pt_pkt_ctx ctx = INTEL_PT_NO_CTX;
2754        struct intel_pt_pkt packet;
2755        int ret;
2756
2757        while (len) {
2758                ret = intel_pt_get_packet(buf, len, &packet, &ctx);
2759                if (ret <= 0)
2760                        return false;
2761                if (packet.type == INTEL_PT_TSC) {
2762                        *tsc = packet.payload;
2763                        *rem = len;
2764                        return true;
2765                }
2766                if (packet.type == INTEL_PT_PSBEND)
2767                        return false;
2768                buf += ret;
2769                len -= ret;
2770        }
2771        return false;
2772}
2773
2774/**
2775 * intel_pt_tsc_cmp - compare 7-byte TSCs.
2776 * @tsc1: first TSC to compare
2777 * @tsc2: second TSC to compare
2778 *
2779 * This function compares 7-byte TSC values allowing for the possibility that
2780 * TSC wrapped around.  Generally it is not possible to know if TSC has wrapped
2781 * around so for that purpose this function assumes the absolute difference is
2782 * less than half the maximum difference.
2783 *
2784 * Return: %-1 if @tsc1 is before @tsc2, %0 if @tsc1 == @tsc2, %1 if @tsc1 is
2785 * after @tsc2.
2786 */
2787static int intel_pt_tsc_cmp(uint64_t tsc1, uint64_t tsc2)
2788{
2789        const uint64_t halfway = (1ULL << 55);
2790
2791        if (tsc1 == tsc2)
2792                return 0;
2793
2794        if (tsc1 < tsc2) {
2795                if (tsc2 - tsc1 < halfway)
2796                        return -1;
2797                else
2798                        return 1;
2799        } else {
2800                if (tsc1 - tsc2 < halfway)
2801                        return 1;
2802                else
2803                        return -1;
2804        }
2805}
2806
2807#define MAX_PADDING (PERF_AUXTRACE_RECORD_ALIGNMENT - 1)
2808
2809/**
2810 * adj_for_padding - adjust overlap to account for padding.
2811 * @buf_b: second buffer
2812 * @buf_a: first buffer
2813 * @len_a: size of first buffer
2814 *
2815 * @buf_a might have up to 7 bytes of padding appended. Adjust the overlap
2816 * accordingly.
2817 *
2818 * Return: A pointer into @buf_b from where non-overlapped data starts
2819 */
2820static unsigned char *adj_for_padding(unsigned char *buf_b,
2821                                      unsigned char *buf_a, size_t len_a)
2822{
2823        unsigned char *p = buf_b - MAX_PADDING;
2824        unsigned char *q = buf_a + len_a - MAX_PADDING;
2825        int i;
2826
2827        for (i = MAX_PADDING; i; i--, p++, q++) {
2828                if (*p != *q)
2829                        break;
2830        }
2831
2832        return p;
2833}
2834
2835/**
2836 * intel_pt_find_overlap_tsc - determine start of non-overlapped trace data
2837 *                             using TSC.
2838 * @buf_a: first buffer
2839 * @len_a: size of first buffer
2840 * @buf_b: second buffer
2841 * @len_b: size of second buffer
2842 * @consecutive: returns true if there is data in buf_b that is consecutive
2843 *               to buf_a
2844 *
2845 * If the trace contains TSC we can look at the last TSC of @buf_a and the
2846 * first TSC of @buf_b in order to determine if the buffers overlap, and then
2847 * walk forward in @buf_b until a later TSC is found.  A precondition is that
2848 * @buf_a and @buf_b are positioned at a PSB.
2849 *
2850 * Return: A pointer into @buf_b from where non-overlapped data starts, or
2851 * @buf_b + @len_b if there is no non-overlapped data.
2852 */
2853static unsigned char *intel_pt_find_overlap_tsc(unsigned char *buf_a,
2854                                                size_t len_a,
2855                                                unsigned char *buf_b,
2856                                                size_t len_b, bool *consecutive)
2857{
2858        uint64_t tsc_a, tsc_b;
2859        unsigned char *p;
2860        size_t len, rem_a, rem_b;
2861
2862        p = intel_pt_last_psb(buf_a, len_a);
2863        if (!p)
2864                return buf_b; /* No PSB in buf_a => no overlap */
2865
2866        len = len_a - (p - buf_a);
2867        if (!intel_pt_next_tsc(p, len, &tsc_a, &rem_a)) {
2868                /* The last PSB+ in buf_a is incomplete, so go back one more */
2869                len_a -= len;
2870                p = intel_pt_last_psb(buf_a, len_a);
2871                if (!p)
2872                        return buf_b; /* No full PSB+ => assume no overlap */
2873                len = len_a - (p - buf_a);
2874                if (!intel_pt_next_tsc(p, len, &tsc_a, &rem_a))
2875                        return buf_b; /* No TSC in buf_a => assume no overlap */
2876        }
2877
2878        while (1) {
2879                /* Ignore PSB+ with no TSC */
2880                if (intel_pt_next_tsc(buf_b, len_b, &tsc_b, &rem_b)) {
2881                        int cmp = intel_pt_tsc_cmp(tsc_a, tsc_b);
2882
2883                        /* Same TSC, so buffers are consecutive */
2884                        if (!cmp && rem_b >= rem_a) {
2885                                unsigned char *start;
2886
2887                                *consecutive = true;
2888                                start = buf_b + len_b - (rem_b - rem_a);
2889                                return adj_for_padding(start, buf_a, len_a);
2890                        }
2891                        if (cmp < 0)
2892                                return buf_b; /* tsc_a < tsc_b => no overlap */
2893                }
2894
2895                if (!intel_pt_step_psb(&buf_b, &len_b))
2896                        return buf_b + len_b; /* No PSB in buf_b => no data */
2897        }
2898}
2899
2900/**
2901 * intel_pt_find_overlap - determine start of non-overlapped trace data.
2902 * @buf_a: first buffer
2903 * @len_a: size of first buffer
2904 * @buf_b: second buffer
2905 * @len_b: size of second buffer
2906 * @have_tsc: can use TSC packets to detect overlap
2907 * @consecutive: returns true if there is data in buf_b that is consecutive
2908 *               to buf_a
2909 *
2910 * When trace samples or snapshots are recorded there is the possibility that
2911 * the data overlaps.  Note that, for the purposes of decoding, data is only
2912 * useful if it begins with a PSB packet.
2913 *
2914 * Return: A pointer into @buf_b from where non-overlapped data starts, or
2915 * @buf_b + @len_b if there is no non-overlapped data.
2916 */
2917unsigned char *intel_pt_find_overlap(unsigned char *buf_a, size_t len_a,
2918                                     unsigned char *buf_b, size_t len_b,
2919                                     bool have_tsc, bool *consecutive)
2920{
2921        unsigned char *found;
2922
2923        /* Buffer 'b' must start at PSB so throw away everything before that */
2924        if (!intel_pt_next_psb(&buf_b, &len_b))
2925                return buf_b + len_b; /* No PSB */
2926
2927        if (!intel_pt_next_psb(&buf_a, &len_a))
2928                return buf_b; /* No overlap */
2929
2930        if (have_tsc) {
2931                found = intel_pt_find_overlap_tsc(buf_a, len_a, buf_b, len_b,
2932                                                  consecutive);
2933                if (found)
2934                        return found;
2935        }
2936
2937        /*
2938         * Buffer 'b' cannot end within buffer 'a' so, for comparison purposes,
2939         * we can ignore the first part of buffer 'a'.
2940         */
2941        while (len_b < len_a) {
2942                if (!intel_pt_step_psb(&buf_a, &len_a))
2943                        return buf_b; /* No overlap */
2944        }
2945
2946        /* Now len_b >= len_a */
2947        while (1) {
2948                /* Potential overlap so check the bytes */
2949                found = memmem(buf_a, len_a, buf_b, len_a);
2950                if (found) {
2951                        *consecutive = true;
2952                        return adj_for_padding(buf_b + len_a, buf_a, len_a);
2953                }
2954
2955                /* Try again at next PSB in buffer 'a' */
2956                if (!intel_pt_step_psb(&buf_a, &len_a))
2957                        return buf_b; /* No overlap */
2958        }
2959}
2960
2961/**
2962 * struct fast_forward_data - data used by intel_pt_ff_cb().
2963 * @timestamp: timestamp to fast forward towards
2964 * @buf_timestamp: buffer timestamp of last buffer with trace data earlier than
2965 *                 the fast forward timestamp.
2966 */
2967struct fast_forward_data {
2968        uint64_t timestamp;
2969        uint64_t buf_timestamp;
2970};
2971
2972/**
2973 * intel_pt_ff_cb - fast forward lookahead callback.
2974 * @buffer: Intel PT trace buffer
2975 * @data: opaque pointer to fast forward data (struct fast_forward_data)
2976 *
2977 * Determine if @buffer trace is past the fast forward timestamp.
2978 *
2979 * Return: 1 (stop lookahead) if @buffer trace is past the fast forward
2980 *         timestamp, and 0 otherwise.
2981 */
2982static int intel_pt_ff_cb(struct intel_pt_buffer *buffer, void *data)
2983{
2984        struct fast_forward_data *d = data;
2985        unsigned char *buf;
2986        uint64_t tsc;
2987        size_t rem;
2988        size_t len;
2989
2990        buf = (unsigned char *)buffer->buf;
2991        len = buffer->len;
2992
2993        if (!intel_pt_next_psb(&buf, &len) ||
2994            !intel_pt_next_tsc(buf, len, &tsc, &rem))
2995                return 0;
2996
2997        tsc = intel_pt_8b_tsc(tsc, buffer->ref_timestamp);
2998
2999        intel_pt_log("Buffer 1st timestamp " x64_fmt " ref timestamp " x64_fmt "\n",
3000                     tsc, buffer->ref_timestamp);
3001
3002        /*
3003         * If the buffer contains a timestamp earlier that the fast forward
3004         * timestamp, then record it, else stop.
3005         */
3006        if (tsc < d->timestamp)
3007                d->buf_timestamp = buffer->ref_timestamp;
3008        else
3009                return 1;
3010
3011        return 0;
3012}
3013
3014/**
3015 * intel_pt_fast_forward - reposition decoder forwards.
3016 * @decoder: Intel PT decoder
3017 * @timestamp: timestamp to fast forward towards
3018 *
3019 * Reposition decoder at the last PSB with a timestamp earlier than @timestamp.
3020 *
3021 * Return: 0 on success or negative error code on failure.
3022 */
3023int intel_pt_fast_forward(struct intel_pt_decoder *decoder, uint64_t timestamp)
3024{
3025        struct fast_forward_data d = { .timestamp = timestamp };
3026        unsigned char *buf;
3027        size_t len;
3028        int err;
3029
3030        intel_pt_log("Fast forward towards timestamp " x64_fmt "\n", timestamp);
3031
3032        /* Find buffer timestamp of buffer to fast forward to */
3033        err = decoder->lookahead(decoder->data, intel_pt_ff_cb, &d);
3034        if (err < 0)
3035                return err;
3036
3037        /* Walk to buffer with same buffer timestamp */
3038        if (d.buf_timestamp) {
3039                do {
3040                        decoder->pos += decoder->len;
3041                        decoder->len = 0;
3042                        err = intel_pt_get_next_data(decoder, true);
3043                        /* -ENOLINK means non-consecutive trace */
3044                        if (err && err != -ENOLINK)
3045                                return err;
3046                } while (decoder->buf_timestamp != d.buf_timestamp);
3047        }
3048
3049        if (!decoder->buf)
3050                return 0;
3051
3052        buf = (unsigned char *)decoder->buf;
3053        len = decoder->len;
3054
3055        if (!intel_pt_next_psb(&buf, &len))
3056                return 0;
3057
3058        /*
3059         * Walk PSBs while the PSB timestamp is less than the fast forward
3060         * timestamp.
3061         */
3062        do {
3063                uint64_t tsc;
3064                size_t rem;
3065
3066                if (!intel_pt_next_tsc(buf, len, &tsc, &rem))
3067                        break;
3068                tsc = intel_pt_8b_tsc(tsc, decoder->buf_timestamp);
3069                /*
3070                 * A TSC packet can slip past MTC packets but, after fast
3071                 * forward, decoding starts at the TSC timestamp. That means
3072                 * the timestamps may not be exactly the same as the timestamps
3073                 * that would have been decoded without fast forward.
3074                 */
3075                if (tsc < timestamp) {
3076                        intel_pt_log("Fast forward to next PSB timestamp " x64_fmt "\n", tsc);
3077                        decoder->pos += decoder->len - len;
3078                        decoder->buf = buf;
3079                        decoder->len = len;
3080                        intel_pt_reposition(decoder);
3081                } else {
3082                        break;
3083                }
3084        } while (intel_pt_step_psb(&buf, &len));
3085
3086        return 0;
3087}
3088