tools/perf/util/jitdump.c

   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
  32 struct 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
  55 struct 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
  62 struct 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
  72 static int
  73 jit_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
 106 static void
 107 jit_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
 116 static int
 117 jit_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
 131 static int
 132 jit_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;
 232 error:
 233         funlockfile(jd->in);
 234         fclose(jd->in);
 235         return retval;
 236 }
 237
 238 static union jr_entry *
 239 jit_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
 355 static int
 356 jit_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
 368 static 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
 385 static 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
 503 static 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
 592 static 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
 618 static int
 619 jit_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
 643 static int
 644 jit_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
 671 static int
 672 jit_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  */
 698 static int
 699 jit_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
 753 int
 754 jit_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 }