linux/tools/perf/util/jitdump.c
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   1// SPDX-License-Identifier: GPL-2.0
   2#include <sys/sysmacros.h>
   3#include <sys/types.h>
   4#include <errno.h>
   5#include <stdio.h>
   6#include <stdlib.h>
   7#include <string.h>
   8#include <fcntl.h>
   9#include <unistd.h>
  10#include <inttypes.h>
  11#include <byteswap.h>
  12#include <sys/stat.h>
  13#include <sys/mman.h>
  14#include <linux/stringify.h>
  15
  16#include "util.h"
  17#include "event.h"
  18#include "debug.h"
  19#include "evlist.h"
  20#include "symbol.h"
  21#include <elf.h>
  22
  23#include "tsc.h"
  24#include "session.h"
  25#include "jit.h"
  26#include "jitdump.h"
  27#include "genelf.h"
  28#include "../builtin.h"
  29
  30#include "sane_ctype.h"
  31
  32struct jit_buf_desc {
  33        struct perf_data_file *output;
  34        struct perf_session *session;
  35        struct machine *machine;
  36        union jr_entry   *entry;
  37        void             *buf;
  38        uint64_t         sample_type;
  39        size_t           bufsize;
  40        FILE             *in;
  41        bool             needs_bswap; /* handles cross-endianess */
  42        bool             use_arch_timestamp;
  43        void             *debug_data;
  44        void             *unwinding_data;
  45        uint64_t         unwinding_size;
  46        uint64_t         unwinding_mapped_size;
  47        uint64_t         eh_frame_hdr_size;
  48        size_t           nr_debug_entries;
  49        uint32_t         code_load_count;
  50        u64              bytes_written;
  51        struct rb_root   code_root;
  52        char             dir[PATH_MAX];
  53};
  54
  55struct debug_line_info {
  56        unsigned long vma;
  57        unsigned int lineno;
  58        /* The filename format is unspecified, absolute path, relative etc. */
  59        char const filename[0];
  60};
  61
  62struct jit_tool {
  63        struct perf_tool tool;
  64        struct perf_data_file   output;
  65        struct perf_data_file   input;
  66        u64 bytes_written;
  67};
  68
  69#define hmax(a, b) ((a) > (b) ? (a) : (b))
  70#define get_jit_tool(t) (container_of(tool, struct jit_tool, tool))
  71
  72static int
  73jit_emit_elf(char *filename,
  74             const char *sym,
  75             uint64_t code_addr,
  76             const void *code,
  77             int csize,
  78             void *debug,
  79             int nr_debug_entries,
  80             void *unwinding,
  81             uint32_t unwinding_header_size,
  82             uint32_t unwinding_size)
  83{
  84        int ret, fd;
  85
  86        if (verbose > 0)
  87                fprintf(stderr, "write ELF image %s\n", filename);
  88
  89        fd = open(filename, O_CREAT|O_TRUNC|O_WRONLY, 0644);
  90        if (fd == -1) {
  91                pr_warning("cannot create jit ELF %s: %s\n", filename, strerror(errno));
  92                return -1;
  93        }
  94
  95        ret = jit_write_elf(fd, code_addr, sym, (const void *)code, csize, debug, nr_debug_entries,
  96                            unwinding, unwinding_header_size, unwinding_size);
  97
  98        close(fd);
  99
 100        if (ret)
 101                unlink(filename);
 102
 103        return ret;
 104}
 105
 106static void
 107jit_close(struct jit_buf_desc *jd)
 108{
 109        if (!(jd && jd->in))
 110                return;
 111        funlockfile(jd->in);
 112        fclose(jd->in);
 113        jd->in = NULL;
 114}
 115
 116static int
 117jit_validate_events(struct perf_session *session)
 118{
 119        struct perf_evsel *evsel;
 120
 121        /*
 122         * check that all events use CLOCK_MONOTONIC
 123         */
 124        evlist__for_each_entry(session->evlist, evsel) {
 125                if (evsel->attr.use_clockid == 0 || evsel->attr.clockid != CLOCK_MONOTONIC)
 126                        return -1;
 127        }
 128        return 0;
 129}
 130
 131static int
 132jit_open(struct jit_buf_desc *jd, const char *name)
 133{
 134        struct jitheader header;
 135        struct jr_prefix *prefix;
 136        ssize_t bs, bsz = 0;
 137        void *n, *buf = NULL;
 138        int ret, retval = -1;
 139
 140        jd->in = fopen(name, "r");
 141        if (!jd->in)
 142                return -1;
 143
 144        bsz = hmax(sizeof(header), sizeof(*prefix));
 145
 146        buf = malloc(bsz);
 147        if (!buf)
 148                goto error;
 149
 150        /*
 151         * protect from writer modifying the file while we are reading it
 152         */
 153        flockfile(jd->in);
 154
 155        ret = fread(buf, sizeof(header), 1, jd->in);
 156        if (ret != 1)
 157                goto error;
 158
 159        memcpy(&header, buf, sizeof(header));
 160
 161        if (header.magic != JITHEADER_MAGIC) {
 162                if (header.magic != JITHEADER_MAGIC_SW)
 163                        goto error;
 164                jd->needs_bswap = true;
 165        }
 166
 167        if (jd->needs_bswap) {
 168                header.version    = bswap_32(header.version);
 169                header.total_size = bswap_32(header.total_size);
 170                header.pid        = bswap_32(header.pid);
 171                header.elf_mach   = bswap_32(header.elf_mach);
 172                header.timestamp  = bswap_64(header.timestamp);
 173                header.flags      = bswap_64(header.flags);
 174        }
 175
 176        jd->use_arch_timestamp = header.flags & JITDUMP_FLAGS_ARCH_TIMESTAMP;
 177
 178        if (verbose > 2)
 179                pr_debug("version=%u\nhdr.size=%u\nts=0x%llx\npid=%d\nelf_mach=%d\nuse_arch_timestamp=%d\n",
 180                        header.version,
 181                        header.total_size,
 182                        (unsigned long long)header.timestamp,
 183                        header.pid,
 184                        header.elf_mach,
 185                        jd->use_arch_timestamp);
 186
 187        if (header.version > JITHEADER_VERSION) {
 188                pr_err("wrong jitdump version %u, expected " __stringify(JITHEADER_VERSION),
 189                        header.version);
 190                goto error;
 191        }
 192
 193        if (header.flags & JITDUMP_FLAGS_RESERVED) {
 194                pr_err("jitdump file contains invalid or unsupported flags 0x%llx\n",
 195                       (unsigned long long)header.flags & JITDUMP_FLAGS_RESERVED);
 196                goto error;
 197        }
 198
 199        if (jd->use_arch_timestamp && !jd->session->time_conv.time_mult) {
 200                pr_err("jitdump file uses arch timestamps but there is no timestamp conversion\n");
 201                goto error;
 202        }
 203
 204        /*
 205         * validate event is using the correct clockid
 206         */
 207        if (!jd->use_arch_timestamp && jit_validate_events(jd->session)) {
 208                pr_err("error, jitted code must be sampled with perf record -k 1\n");
 209                goto error;
 210        }
 211
 212        bs = header.total_size - sizeof(header);
 213
 214        if (bs > bsz) {
 215                n = realloc(buf, bs);
 216                if (!n)
 217                        goto error;
 218                bsz = bs;
 219                buf = n;
 220                /* read extra we do not know about */
 221                ret = fread(buf, bs - bsz, 1, jd->in);
 222                if (ret != 1)
 223                        goto error;
 224        }
 225        /*
 226         * keep dirname for generating files and mmap records
 227         */
 228        strcpy(jd->dir, name);
 229        dirname(jd->dir);
 230
 231        return 0;
 232error:
 233        funlockfile(jd->in);
 234        fclose(jd->in);
 235        return retval;
 236}
 237
 238static union jr_entry *
 239jit_get_next_entry(struct jit_buf_desc *jd)
 240{
 241        struct jr_prefix *prefix;
 242        union jr_entry *jr;
 243        void *addr;
 244        size_t bs, size;
 245        int id, ret;
 246
 247        if (!(jd && jd->in))
 248                return NULL;
 249
 250        if (jd->buf == NULL) {
 251                size_t sz = getpagesize();
 252                if (sz < sizeof(*prefix))
 253                        sz = sizeof(*prefix);
 254
 255                jd->buf = malloc(sz);
 256                if (jd->buf == NULL)
 257                        return NULL;
 258
 259                jd->bufsize = sz;
 260        }
 261
 262        prefix = jd->buf;
 263
 264        /*
 265         * file is still locked at this point
 266         */
 267        ret = fread(prefix, sizeof(*prefix), 1, jd->in);
 268        if (ret  != 1)
 269                return NULL;
 270
 271        if (jd->needs_bswap) {
 272                prefix->id         = bswap_32(prefix->id);
 273                prefix->total_size = bswap_32(prefix->total_size);
 274                prefix->timestamp  = bswap_64(prefix->timestamp);
 275        }
 276        id   = prefix->id;
 277        size = prefix->total_size;
 278
 279        bs = (size_t)size;
 280        if (bs < sizeof(*prefix))
 281                return NULL;
 282
 283        if (id >= JIT_CODE_MAX) {
 284                pr_warning("next_entry: unknown record type %d, skipping\n", id);
 285        }
 286        if (bs > jd->bufsize) {
 287                void *n;
 288                n = realloc(jd->buf, bs);
 289                if (!n)
 290                        return NULL;
 291                jd->buf = n;
 292                jd->bufsize = bs;
 293        }
 294
 295        addr = ((void *)jd->buf) + sizeof(*prefix);
 296
 297        ret = fread(addr, bs - sizeof(*prefix), 1, jd->in);
 298        if (ret != 1)
 299                return NULL;
 300
 301        jr = (union jr_entry *)jd->buf;
 302
 303        switch(id) {
 304        case JIT_CODE_DEBUG_INFO:
 305                if (jd->needs_bswap) {
 306                        uint64_t n;
 307                        jr->info.code_addr = bswap_64(jr->info.code_addr);
 308                        jr->info.nr_entry  = bswap_64(jr->info.nr_entry);
 309                        for (n = 0 ; n < jr->info.nr_entry; n++) {
 310                                jr->info.entries[n].addr    = bswap_64(jr->info.entries[n].addr);
 311                                jr->info.entries[n].lineno  = bswap_32(jr->info.entries[n].lineno);
 312                                jr->info.entries[n].discrim = bswap_32(jr->info.entries[n].discrim);
 313                        }
 314                }
 315                break;
 316        case JIT_CODE_UNWINDING_INFO:
 317                if (jd->needs_bswap) {
 318                        jr->unwinding.unwinding_size = bswap_64(jr->unwinding.unwinding_size);
 319                        jr->unwinding.eh_frame_hdr_size = bswap_64(jr->unwinding.eh_frame_hdr_size);
 320                        jr->unwinding.mapped_size = bswap_64(jr->unwinding.mapped_size);
 321                }
 322                break;
 323        case JIT_CODE_CLOSE:
 324                break;
 325        case JIT_CODE_LOAD:
 326                if (jd->needs_bswap) {
 327                        jr->load.pid       = bswap_32(jr->load.pid);
 328                        jr->load.tid       = bswap_32(jr->load.tid);
 329                        jr->load.vma       = bswap_64(jr->load.vma);
 330                        jr->load.code_addr = bswap_64(jr->load.code_addr);
 331                        jr->load.code_size = bswap_64(jr->load.code_size);
 332                        jr->load.code_index= bswap_64(jr->load.code_index);
 333                }
 334                jd->code_load_count++;
 335                break;
 336        case JIT_CODE_MOVE:
 337                if (jd->needs_bswap) {
 338                        jr->move.pid           = bswap_32(jr->move.pid);
 339                        jr->move.tid           = bswap_32(jr->move.tid);
 340                        jr->move.vma           = bswap_64(jr->move.vma);
 341                        jr->move.old_code_addr = bswap_64(jr->move.old_code_addr);
 342                        jr->move.new_code_addr = bswap_64(jr->move.new_code_addr);
 343                        jr->move.code_size     = bswap_64(jr->move.code_size);
 344                        jr->move.code_index    = bswap_64(jr->move.code_index);
 345                }
 346                break;
 347        case JIT_CODE_MAX:
 348        default:
 349                /* skip unknown record (we have read them) */
 350                break;
 351        }
 352        return jr;
 353}
 354
 355static int
 356jit_inject_event(struct jit_buf_desc *jd, union perf_event *event)
 357{
 358        ssize_t size;
 359
 360        size = perf_data_file__write(jd->output, event, event->header.size);
 361        if (size < 0)
 362                return -1;
 363
 364        jd->bytes_written += size;
 365        return 0;
 366}
 367
 368static uint64_t convert_timestamp(struct jit_buf_desc *jd, uint64_t timestamp)
 369{
 370        struct perf_tsc_conversion tc;
 371
 372        if (!jd->use_arch_timestamp)
 373                return timestamp;
 374
 375        tc.time_shift = jd->session->time_conv.time_shift;
 376        tc.time_mult  = jd->session->time_conv.time_mult;
 377        tc.time_zero  = jd->session->time_conv.time_zero;
 378
 379        if (!tc.time_mult)
 380                return 0;
 381
 382        return tsc_to_perf_time(timestamp, &tc);
 383}
 384
 385static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
 386{
 387        struct perf_sample sample;
 388        union perf_event *event;
 389        struct perf_tool *tool = jd->session->tool;
 390        uint64_t code, addr;
 391        uintptr_t uaddr;
 392        char *filename;
 393        struct stat st;
 394        size_t size;
 395        u16 idr_size;
 396        const char *sym;
 397        uint32_t count;
 398        int ret, csize, usize;
 399        pid_t pid, tid;
 400        struct {
 401                u32 pid, tid;
 402                u64 time;
 403        } *id;
 404
 405        pid   = jr->load.pid;
 406        tid   = jr->load.tid;
 407        csize = jr->load.code_size;
 408        usize = jd->unwinding_mapped_size;
 409        addr  = jr->load.code_addr;
 410        sym   = (void *)((unsigned long)jr + sizeof(jr->load));
 411        code  = (unsigned long)jr + jr->load.p.total_size - csize;
 412        count = jr->load.code_index;
 413        idr_size = jd->machine->id_hdr_size;
 414
 415        event = calloc(1, sizeof(*event) + idr_size);
 416        if (!event)
 417                return -1;
 418
 419        filename = event->mmap2.filename;
 420        size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%u.so",
 421                        jd->dir,
 422                        pid,
 423                        count);
 424
 425        size++; /* for \0 */
 426
 427        size = PERF_ALIGN(size, sizeof(u64));
 428        uaddr = (uintptr_t)code;
 429        ret = jit_emit_elf(filename, sym, addr, (const void *)uaddr, csize, jd->debug_data, jd->nr_debug_entries,
 430                           jd->unwinding_data, jd->eh_frame_hdr_size, jd->unwinding_size);
 431
 432        if (jd->debug_data && jd->nr_debug_entries) {
 433                free(jd->debug_data);
 434                jd->debug_data = NULL;
 435                jd->nr_debug_entries = 0;
 436        }
 437
 438        if (jd->unwinding_data && jd->eh_frame_hdr_size) {
 439                free(jd->unwinding_data);
 440                jd->unwinding_data = NULL;
 441                jd->eh_frame_hdr_size = 0;
 442                jd->unwinding_mapped_size = 0;
 443                jd->unwinding_size = 0;
 444        }
 445
 446        if (ret) {
 447                free(event);
 448                return -1;
 449        }
 450        if (stat(filename, &st))
 451                memset(&st, 0, sizeof(st));
 452
 453        event->mmap2.header.type = PERF_RECORD_MMAP2;
 454        event->mmap2.header.misc = PERF_RECORD_MISC_USER;
 455        event->mmap2.header.size = (sizeof(event->mmap2) -
 456                        (sizeof(event->mmap2.filename) - size) + idr_size);
 457
 458        event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
 459        event->mmap2.start = addr;
 460        event->mmap2.len   = usize ? ALIGN_8(csize) + usize : csize;
 461        event->mmap2.pid   = pid;
 462        event->mmap2.tid   = tid;
 463        event->mmap2.ino   = st.st_ino;
 464        event->mmap2.maj   = major(st.st_dev);
 465        event->mmap2.min   = minor(st.st_dev);
 466        event->mmap2.prot  = st.st_mode;
 467        event->mmap2.flags = MAP_SHARED;
 468        event->mmap2.ino_generation = 1;
 469
 470        id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
 471        if (jd->sample_type & PERF_SAMPLE_TID) {
 472                id->pid  = pid;
 473                id->tid  = tid;
 474        }
 475        if (jd->sample_type & PERF_SAMPLE_TIME)
 476                id->time = convert_timestamp(jd, jr->load.p.timestamp);
 477
 478        /*
 479         * create pseudo sample to induce dso hit increment
 480         * use first address as sample address
 481         */
 482        memset(&sample, 0, sizeof(sample));
 483        sample.cpumode = PERF_RECORD_MISC_USER;
 484        sample.pid  = pid;
 485        sample.tid  = tid;
 486        sample.time = id->time;
 487        sample.ip   = addr;
 488
 489        ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
 490        if (ret)
 491                return ret;
 492
 493        ret = jit_inject_event(jd, event);
 494        /*
 495         * mark dso as use to generate buildid in the header
 496         */
 497        if (!ret)
 498                build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
 499
 500        return ret;
 501}
 502
 503static int jit_repipe_code_move(struct jit_buf_desc *jd, union jr_entry *jr)
 504{
 505        struct perf_sample sample;
 506        union perf_event *event;
 507        struct perf_tool *tool = jd->session->tool;
 508        char *filename;
 509        size_t size;
 510        struct stat st;
 511        int usize;
 512        u16 idr_size;
 513        int ret;
 514        pid_t pid, tid;
 515        struct {
 516                u32 pid, tid;
 517                u64 time;
 518        } *id;
 519
 520        pid = jr->move.pid;
 521        tid =  jr->move.tid;
 522        usize = jd->unwinding_mapped_size;
 523        idr_size = jd->machine->id_hdr_size;
 524
 525        /*
 526         * +16 to account for sample_id_all (hack)
 527         */
 528        event = calloc(1, sizeof(*event) + 16);
 529        if (!event)
 530                return -1;
 531
 532        filename = event->mmap2.filename;
 533        size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%"PRIu64,
 534                 jd->dir,
 535                 pid,
 536                 jr->move.code_index);
 537
 538        size++; /* for \0 */
 539
 540        if (stat(filename, &st))
 541                memset(&st, 0, sizeof(st));
 542
 543        size = PERF_ALIGN(size, sizeof(u64));
 544
 545        event->mmap2.header.type = PERF_RECORD_MMAP2;
 546        event->mmap2.header.misc = PERF_RECORD_MISC_USER;
 547        event->mmap2.header.size = (sizeof(event->mmap2) -
 548                        (sizeof(event->mmap2.filename) - size) + idr_size);
 549        event->mmap2.pgoff = GEN_ELF_TEXT_OFFSET;
 550        event->mmap2.start = jr->move.new_code_addr;
 551        event->mmap2.len   = usize ? ALIGN_8(jr->move.code_size) + usize
 552                                   : jr->move.code_size;
 553        event->mmap2.pid   = pid;
 554        event->mmap2.tid   = tid;
 555        event->mmap2.ino   = st.st_ino;
 556        event->mmap2.maj   = major(st.st_dev);
 557        event->mmap2.min   = minor(st.st_dev);
 558        event->mmap2.prot  = st.st_mode;
 559        event->mmap2.flags = MAP_SHARED;
 560        event->mmap2.ino_generation = 1;
 561
 562        id = (void *)((unsigned long)event + event->mmap.header.size - idr_size);
 563        if (jd->sample_type & PERF_SAMPLE_TID) {
 564                id->pid  = pid;
 565                id->tid  = tid;
 566        }
 567        if (jd->sample_type & PERF_SAMPLE_TIME)
 568                id->time = convert_timestamp(jd, jr->load.p.timestamp);
 569
 570        /*
 571         * create pseudo sample to induce dso hit increment
 572         * use first address as sample address
 573         */
 574        memset(&sample, 0, sizeof(sample));
 575        sample.cpumode = PERF_RECORD_MISC_USER;
 576        sample.pid  = pid;
 577        sample.tid  = tid;
 578        sample.time = id->time;
 579        sample.ip   = jr->move.new_code_addr;
 580
 581        ret = perf_event__process_mmap2(tool, event, &sample, jd->machine);
 582        if (ret)
 583                return ret;
 584
 585        ret = jit_inject_event(jd, event);
 586        if (!ret)
 587                build_id__mark_dso_hit(tool, event, &sample, NULL, jd->machine);
 588
 589        return ret;
 590}
 591
 592static int jit_repipe_debug_info(struct jit_buf_desc *jd, union jr_entry *jr)
 593{
 594        void *data;
 595        size_t sz;
 596
 597        if (!(jd && jr))
 598                return -1;
 599
 600        sz  = jr->prefix.total_size - sizeof(jr->info);
 601        data = malloc(sz);
 602        if (!data)
 603                return -1;
 604
 605        memcpy(data, &jr->info.entries, sz);
 606
 607        jd->debug_data       = data;
 608
 609        /*
 610         * we must use nr_entry instead of size here because
 611         * we cannot distinguish actual entry from padding otherwise
 612         */
 613        jd->nr_debug_entries = jr->info.nr_entry;
 614
 615        return 0;
 616}
 617
 618static int
 619jit_repipe_unwinding_info(struct jit_buf_desc *jd, union jr_entry *jr)
 620{
 621        void *unwinding_data;
 622        uint32_t unwinding_data_size;
 623
 624        if (!(jd && jr))
 625                return -1;
 626
 627        unwinding_data_size  = jr->prefix.total_size - sizeof(jr->unwinding);
 628        unwinding_data = malloc(unwinding_data_size);
 629        if (!unwinding_data)
 630                return -1;
 631
 632        memcpy(unwinding_data, &jr->unwinding.unwinding_data,
 633               unwinding_data_size);
 634
 635        jd->eh_frame_hdr_size = jr->unwinding.eh_frame_hdr_size;
 636        jd->unwinding_size = jr->unwinding.unwinding_size;
 637        jd->unwinding_mapped_size = jr->unwinding.mapped_size;
 638        jd->unwinding_data = unwinding_data;
 639
 640        return 0;
 641}
 642
 643static int
 644jit_process_dump(struct jit_buf_desc *jd)
 645{
 646        union jr_entry *jr;
 647        int ret = 0;
 648
 649        while ((jr = jit_get_next_entry(jd))) {
 650                switch(jr->prefix.id) {
 651                case JIT_CODE_LOAD:
 652                        ret = jit_repipe_code_load(jd, jr);
 653                        break;
 654                case JIT_CODE_MOVE:
 655                        ret = jit_repipe_code_move(jd, jr);
 656                        break;
 657                case JIT_CODE_DEBUG_INFO:
 658                        ret = jit_repipe_debug_info(jd, jr);
 659                        break;
 660                case JIT_CODE_UNWINDING_INFO:
 661                        ret = jit_repipe_unwinding_info(jd, jr);
 662                        break;
 663                default:
 664                        ret = 0;
 665                        continue;
 666                }
 667        }
 668        return ret;
 669}
 670
 671static int
 672jit_inject(struct jit_buf_desc *jd, char *path)
 673{
 674        int ret;
 675
 676        if (verbose > 0)
 677                fprintf(stderr, "injecting: %s\n", path);
 678
 679        ret = jit_open(jd, path);
 680        if (ret)
 681                return -1;
 682
 683        ret = jit_process_dump(jd);
 684
 685        jit_close(jd);
 686
 687        if (verbose > 0)
 688                fprintf(stderr, "injected: %s (%d)\n", path, ret);
 689
 690        return 0;
 691}
 692
 693/*
 694 * File must be with pattern .../jit-XXXX.dump
 695 * where XXXX is the PID of the process which did the mmap()
 696 * as captured in the RECORD_MMAP record
 697 */
 698static int
 699jit_detect(char *mmap_name, pid_t pid)
 700 {
 701        char *p;
 702        char *end = NULL;
 703        pid_t pid2;
 704
 705        if (verbose > 2)
 706                fprintf(stderr, "jit marker trying : %s\n", mmap_name);
 707        /*
 708         * get file name
 709         */
 710        p = strrchr(mmap_name, '/');
 711        if (!p)
 712                return -1;
 713
 714        /*
 715         * match prefix
 716         */
 717        if (strncmp(p, "/jit-", 5))
 718                return -1;
 719
 720        /*
 721         * skip prefix
 722         */
 723        p += 5;
 724
 725        /*
 726         * must be followed by a pid
 727         */
 728        if (!isdigit(*p))
 729                return -1;
 730
 731        pid2 = (int)strtol(p, &end, 10);
 732        if (!end)
 733                return -1;
 734
 735        /*
 736         * pid does not match mmap pid
 737         * pid==0 in system-wide mode (synthesized)
 738         */
 739        if (pid && pid2 != pid)
 740                return -1;
 741        /*
 742         * validate suffix
 743         */
 744        if (strcmp(end, ".dump"))
 745                return -1;
 746
 747        if (verbose > 0)
 748                fprintf(stderr, "jit marker found: %s\n", mmap_name);
 749
 750        return 0;
 751}
 752
 753int
 754jit_process(struct perf_session *session,
 755            struct perf_data_file *output,
 756            struct machine *machine,
 757            char *filename,
 758            pid_t pid,
 759            u64 *nbytes)
 760{
 761        struct perf_evsel *first;
 762        struct jit_buf_desc jd;
 763        int ret;
 764
 765        /*
 766         * first, detect marker mmap (i.e., the jitdump mmap)
 767         */
 768        if (jit_detect(filename, pid))
 769                return 0;
 770
 771        memset(&jd, 0, sizeof(jd));
 772
 773        jd.session = session;
 774        jd.output  = output;
 775        jd.machine = machine;
 776
 777        /*
 778         * track sample_type to compute id_all layout
 779         * perf sets the same sample type to all events as of now
 780         */
 781        first = perf_evlist__first(session->evlist);
 782        jd.sample_type = first->attr.sample_type;
 783
 784        *nbytes = 0;
 785
 786        ret = jit_inject(&jd, filename);
 787        if (!ret) {
 788                *nbytes = jd.bytes_written;
 789                ret = 1;
 790        }
 791
 792        return ret;
 793}
 794