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 <libgen.h>
   6 #include <stdio.h>
   7 #include <stdlib.h>
   8 #include <string.h>
   9 #include <fcntl.h>
  10 #include <unistd.h>
  11 #include <inttypes.h>
  12 #include <byteswap.h>
  13 #include <sys/stat.h>
  14 #include <sys/mman.h>
  15 #include <linux/stringify.h>
  16
  17 #include "build-id.h"
  18 #include "event.h"
  19 #include "debug.h"
  20 #include "evlist.h"
  21 #include "symbol.h"
  22 #include <elf.h>
  23
  24 #include "tsc.h"
  25 #include "session.h"
  26 #include "jit.h"
  27 #include "jitdump.h"
  28 #include "genelf.h"
  29 #include "thread.h"
  30
  31 #include <linux/ctype.h>
  32 #include <linux/zalloc.h>
  33
  34 struct jit_buf_desc {
  35         struct perf_data *output;
  36         struct perf_session *session;
  37         struct machine *machine;
  38         union jr_entry   *entry;
  39         void             *buf;
  40         uint64_t         sample_type;
  41         size_t           bufsize;
  42         FILE             *in;
  43         bool             needs_bswap; /* handles cross-endianness */
  44         bool             use_arch_timestamp;
  45         void             *debug_data;
  46         void             *unwinding_data;
  47         uint64_t         unwinding_size;
  48         uint64_t         unwinding_mapped_size;
  49         uint64_t         eh_frame_hdr_size;
  50         size_t           nr_debug_entries;
  51         uint32_t         code_load_count;
  52         u64              bytes_written;
  53         struct rb_root   code_root;
  54         char             dir[PATH_MAX];
  55 };
  56
  57 struct debug_line_info {
  58         unsigned long vma;
  59         unsigned int lineno;
  60         /* The filename format is unspecified, absolute path, relative etc. */
  61         char const filename[];
  62 };
  63
  64 struct jit_tool {
  65         struct perf_tool tool;
  66         struct perf_data        output;
  67         struct perf_data        input;
  68         u64 bytes_written;
  69 };
  70
  71 #define hmax(a, b) ((a) > (b) ? (a) : (b))
  72 #define get_jit_tool(t) (container_of(tool, struct jit_tool, tool))
  73
  74 static int
  75 jit_emit_elf(char *filename,
  76              const char *sym,
  77              uint64_t code_addr,
  78              const void *code,
  79              int csize,
  80              void *debug,
  81              int nr_debug_entries,
  82              void *unwinding,
  83              uint32_t unwinding_header_size,
  84              uint32_t unwinding_size)
  85 {
  86         int ret, fd;
  87
  88         if (verbose > 0)
  89                 fprintf(stderr, "write ELF image %s\n", filename);
  90
  91         fd = open(filename, O_CREAT|O_TRUNC|O_WRONLY, 0644);
  92         if (fd == -1) {
  93                 pr_warning("cannot create jit ELF %s: %s\n", filename, strerror(errno));
  94                 return -1;
  95         }
  96
  97         ret = jit_write_elf(fd, code_addr, sym, (const void *)code, csize, debug, nr_debug_entries,
  98                             unwinding, unwinding_header_size, unwinding_size);
  99
 100         close(fd);
 101
 102         if (ret)
 103                 unlink(filename);
 104
 105         return ret;
 106 }
 107
 108 static void
 109 jit_close(struct jit_buf_desc *jd)
 110 {
 111         if (!(jd && jd->in))
 112                 return;
 113         funlockfile(jd->in);
 114         fclose(jd->in);
 115         jd->in = NULL;
 116 }
 117
 118 static int
 119 jit_validate_events(struct perf_session *session)
 120 {
 121         struct evsel *evsel;
 122
 123         /*
 124          * check that all events use CLOCK_MONOTONIC
 125          */
 126         evlist__for_each_entry(session->evlist, evsel) {
 127                 if (evsel->core.attr.use_clockid == 0 || evsel->core.attr.clockid != CLOCK_MONOTONIC)
 128                         return -1;
 129         }
 130         return 0;
 131 }
 132
 133 static int
 134 jit_open(struct jit_buf_desc *jd, const char *name)
 135 {
 136         struct jitheader header;
 137         struct jr_prefix *prefix;
 138         ssize_t bs, bsz = 0;
 139         void *n, *buf = NULL;
 140         int ret, retval = -1;
 141
 142         jd->in = fopen(name, "r");
 143         if (!jd->in)
 144                 return -1;
 145
 146         bsz = hmax(sizeof(header), sizeof(*prefix));
 147
 148         buf = malloc(bsz);
 149         if (!buf)
 150                 goto error;
 151
 152         /*
 153          * protect from writer modifying the file while we are reading it
 154          */
 155         flockfile(jd->in);
 156
 157         ret = fread(buf, sizeof(header), 1, jd->in);
 158         if (ret != 1)
 159                 goto error;
 160
 161         memcpy(&header, buf, sizeof(header));
 162
 163         if (header.magic != JITHEADER_MAGIC) {
 164                 if (header.magic != JITHEADER_MAGIC_SW)
 165                         goto error;
 166                 jd->needs_bswap = true;
 167         }
 168
 169         if (jd->needs_bswap) {
 170                 header.version    = bswap_32(header.version);
 171                 header.total_size = bswap_32(header.total_size);
 172                 header.pid        = bswap_32(header.pid);
 173                 header.elf_mach   = bswap_32(header.elf_mach);
 174                 header.timestamp  = bswap_64(header.timestamp);
 175                 header.flags      = bswap_64(header.flags);
 176         }
 177
 178         jd->use_arch_timestamp = header.flags & JITDUMP_FLAGS_ARCH_TIMESTAMP;
 179
 180         if (verbose > 2)
 181                 pr_debug("version=%u\nhdr.size=%u\nts=0x%llx\npid=%d\nelf_mach=%d\nuse_arch_timestamp=%d\n",
 182                         header.version,
 183                         header.total_size,
 184                         (unsigned long long)header.timestamp,
 185                         header.pid,
 186                         header.elf_mach,
 187                         jd->use_arch_timestamp);
 188
 189         if (header.version > JITHEADER_VERSION) {
 190                 pr_err("wrong jitdump version %u, expected " __stringify(JITHEADER_VERSION),
 191                         header.version);
 192                 goto error;
 193         }
 194
 195         if (header.flags & JITDUMP_FLAGS_RESERVED) {
 196                 pr_err("jitdump file contains invalid or unsupported flags 0x%llx\n",
 197                        (unsigned long long)header.flags & JITDUMP_FLAGS_RESERVED);
 198                 goto error;
 199         }
 200
 201         if (jd->use_arch_timestamp && !jd->session->time_conv.time_mult) {
 202                 pr_err("jitdump file uses arch timestamps but there is no timestamp conversion\n");
 203                 goto error;
 204         }
 205
 206         /*
 207          * validate event is using the correct clockid
 208          */
 209         if (!jd->use_arch_timestamp && jit_validate_events(jd->session)) {
 210                 pr_err("error, jitted code must be sampled with perf record -k 1\n");
 211                 goto error;
 212         }
 213
 214         bs = header.total_size - sizeof(header);
 215
 216         if (bs > bsz) {
 217                 n = realloc(buf, bs);
 218                 if (!n)
 219                         goto error;
 220                 bsz = bs;
 221                 buf = n;
 222                 /* read extra we do not know about */
 223                 ret = fread(buf, bs - bsz, 1, jd->in);
 224                 if (ret != 1)
 225                         goto error;
 226         }
 227         /*
 228          * keep dirname for generating files and mmap records
 229          */
 230         strcpy(jd->dir, name);
 231         dirname(jd->dir);
 232
 233         return 0;
 234 error:
 235         funlockfile(jd->in);
 236         fclose(jd->in);
 237         return retval;
 238 }
 239
 240 static union jr_entry *
 241 jit_get_next_entry(struct jit_buf_desc *jd)
 242 {
 243         struct jr_prefix *prefix;
 244         union jr_entry *jr;
 245         void *addr;
 246         size_t bs, size;
 247         int id, ret;
 248
 249         if (!(jd && jd->in))
 250                 return NULL;
 251
 252         if (jd->buf == NULL) {
 253                 size_t sz = getpagesize();
 254                 if (sz < sizeof(*prefix))
 255                         sz = sizeof(*prefix);
 256
 257                 jd->buf = malloc(sz);
 258                 if (jd->buf == NULL)
 259                         return NULL;
 260
 261                 jd->bufsize = sz;
 262         }
 263
 264         prefix = jd->buf;
 265
 266         /*
 267          * file is still locked at this point
 268          */
 269         ret = fread(prefix, sizeof(*prefix), 1, jd->in);
 270         if (ret  != 1)
 271                 return NULL;
 272
 273         if (jd->needs_bswap) {
 274                 prefix->id         = bswap_32(prefix->id);
 275                 prefix->total_size = bswap_32(prefix->total_size);
 276                 prefix->timestamp  = bswap_64(prefix->timestamp);
 277         }
 278         id   = prefix->id;
 279         size = prefix->total_size;
 280
 281         bs = (size_t)size;
 282         if (bs < sizeof(*prefix))
 283                 return NULL;
 284
 285         if (id >= JIT_CODE_MAX) {
 286                 pr_warning("next_entry: unknown record type %d, skipping\n", id);
 287         }
 288         if (bs > jd->bufsize) {
 289                 void *n;
 290                 n = realloc(jd->buf, bs);
 291                 if (!n)
 292                         return NULL;
 293                 jd->buf = n;
 294                 jd->bufsize = bs;
 295         }
 296
 297         addr = ((void *)jd->buf) + sizeof(*prefix);
 298
 299         ret = fread(addr, bs - sizeof(*prefix), 1, jd->in);
 300         if (ret != 1)
 301                 return NULL;
 302
 303         jr = (union jr_entry *)jd->buf;
 304
 305         switch(id) {
 306         case JIT_CODE_DEBUG_INFO:
 307                 if (jd->needs_bswap) {
 308                         uint64_t n;
 309                         jr->info.code_addr = bswap_64(jr->info.code_addr);
 310                         jr->info.nr_entry  = bswap_64(jr->info.nr_entry);
 311                         for (n = 0 ; n < jr->info.nr_entry; n++) {
 312                                 jr->info.entries[n].addr    = bswap_64(jr->info.entries[n].addr);
 313                                 jr->info.entries[n].lineno  = bswap_32(jr->info.entries[n].lineno);
 314                                 jr->info.entries[n].discrim = bswap_32(jr->info.entries[n].discrim);
 315                         }
 316                 }
 317                 break;
 318         case JIT_CODE_UNWINDING_INFO:
 319                 if (jd->needs_bswap) {
 320                         jr->unwinding.unwinding_size = bswap_64(jr->unwinding.unwinding_size);
 321                         jr->unwinding.eh_frame_hdr_size = bswap_64(jr->unwinding.eh_frame_hdr_size);
 322                         jr->unwinding.mapped_size = bswap_64(jr->unwinding.mapped_size);
 323                 }
 324                 break;
 325         case JIT_CODE_CLOSE:
 326                 break;
 327         case JIT_CODE_LOAD:
 328                 if (jd->needs_bswap) {
 329                         jr->load.pid       = bswap_32(jr->load.pid);
 330                         jr->load.tid       = bswap_32(jr->load.tid);
 331                         jr->load.vma       = bswap_64(jr->load.vma);
 332                         jr->load.code_addr = bswap_64(jr->load.code_addr);
 333                         jr->load.code_size = bswap_64(jr->load.code_size);
 334                         jr->load.code_index= bswap_64(jr->load.code_index);
 335                 }
 336                 jd->code_load_count++;
 337                 break;
 338         case JIT_CODE_MOVE:
 339                 if (jd->needs_bswap) {
 340                         jr->move.pid           = bswap_32(jr->move.pid);
 341                         jr->move.tid           = bswap_32(jr->move.tid);
 342                         jr->move.vma           = bswap_64(jr->move.vma);
 343                         jr->move.old_code_addr = bswap_64(jr->move.old_code_addr);
 344                         jr->move.new_code_addr = bswap_64(jr->move.new_code_addr);
 345                         jr->move.code_size     = bswap_64(jr->move.code_size);
 346                         jr->move.code_index    = bswap_64(jr->move.code_index);
 347                 }
 348                 break;
 349         case JIT_CODE_MAX:
 350         default:
 351                 /* skip unknown record (we have read them) */
 352                 break;
 353         }
 354         return jr;
 355 }
 356
 357 static int
 358 jit_inject_event(struct jit_buf_desc *jd, union perf_event *event)
 359 {
 360         ssize_t size;
 361
 362         size = perf_data__write(jd->output, event, event->header.size);
 363         if (size < 0)
 364                 return -1;
 365
 366         jd->bytes_written += size;
 367         return 0;
 368 }
 369
 370 static uint64_t convert_timestamp(struct jit_buf_desc *jd, uint64_t timestamp)
 371 {
 372         struct perf_tsc_conversion tc;
 373
 374         if (!jd->use_arch_timestamp)
 375                 return timestamp;
 376
 377         tc.time_shift = jd->session->time_conv.time_shift;
 378         tc.time_mult  = jd->session->time_conv.time_mult;
 379         tc.time_zero  = jd->session->time_conv.time_zero;
 380
 381         if (!tc.time_mult)
 382                 return 0;
 383
 384         return tsc_to_perf_time(timestamp, &tc);
 385 }
 386
 387 static int jit_repipe_code_load(struct jit_buf_desc *jd, union jr_entry *jr)
 388 {
 389         struct perf_sample sample;
 390         union perf_event *event;
 391         struct perf_tool *tool = jd->session->tool;
 392         uint64_t code, addr;
 393         uintptr_t uaddr;
 394         char *filename;
 395         struct stat st;
 396         size_t size;
 397         u16 idr_size;
 398         const char *sym;
 399         uint64_t count;
 400         int ret, csize, usize;
 401         pid_t pid, tid;
 402         struct {
 403                 u32 pid, tid;
 404                 u64 time;
 405         } *id;
 406
 407         pid   = jr->load.pid;
 408         tid   = jr->load.tid;
 409         csize = jr->load.code_size;
 410         usize = jd->unwinding_mapped_size;
 411         addr  = jr->load.code_addr;
 412         sym   = (void *)((unsigned long)jr + sizeof(jr->load));
 413         code  = (unsigned long)jr + jr->load.p.total_size - csize;
 414         count = jr->load.code_index;
 415         idr_size = jd->machine->id_hdr_size;
 416
 417         event = calloc(1, sizeof(*event) + idr_size);
 418         if (!event)
 419                 return -1;
 420
 421         filename = event->mmap2.filename;
 422         size = snprintf(filename, PATH_MAX, "%s/jitted-%d-%" PRIu64 ".so",
 423                         jd->dir,
 424                         pid,
 425                         count);
 426
 427         size++; /* for \0 */
 428
 429         size = PERF_ALIGN(size, sizeof(u64));
 430         uaddr = (uintptr_t)code;
 431         ret = jit_emit_elf(filename, sym, addr, (const void *)uaddr, csize, jd->debug_data, jd->nr_debug_entries,
 432                            jd->unwinding_data, jd->eh_frame_hdr_size, jd->unwinding_size);
 433
 434         if (jd->debug_data && jd->nr_debug_entries) {
 435                 zfree(&jd->debug_data);
 436                 jd->nr_debug_entries = 0;
 437         }
 438
 439         if (jd->unwinding_data && jd->eh_frame_hdr_size) {
 440                 zfree(&jd->unwinding_data);
 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 ".so",
 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 static void jit_add_pid(struct machine *machine, pid_t pid)
 754 {
 755         struct thread *thread = machine__findnew_thread(machine, pid, pid);
 756
 757         if (!thread) {
 758                 pr_err("%s: thread %d not found or created\n", __func__, pid);
 759                 return;
 760         }
 761
 762         thread->priv = (void *)1;
 763 }
 764
 765 static bool jit_has_pid(struct machine *machine, pid_t pid)
 766 {
 767         struct thread *thread = machine__find_thread(machine, pid, pid);
 768
 769         if (!thread)
 770                 return 0;
 771
 772         return (bool)thread->priv;
 773 }
 774
 775 int
 776 jit_process(struct perf_session *session,
 777             struct perf_data *output,
 778             struct machine *machine,
 779             char *filename,
 780             pid_t pid,
 781             u64 *nbytes)
 782 {
 783         struct evsel *first;
 784         struct jit_buf_desc jd;
 785         int ret;
 786
 787         /*
 788          * first, detect marker mmap (i.e., the jitdump mmap)
 789          */
 790         if (jit_detect(filename, pid)) {
 791                 // Strip //anon* mmaps if we processed a jitdump for this pid
 792                 if (jit_has_pid(machine, pid) && (strncmp(filename, "//anon", 6) == 0))
 793                         return 1;
 794
 795                 return 0;
 796         }
 797
 798         memset(&jd, 0, sizeof(jd));
 799
 800         jd.session = session;
 801         jd.output  = output;
 802         jd.machine = machine;
 803
 804         /*
 805          * track sample_type to compute id_all layout
 806          * perf sets the same sample type to all events as of now
 807          */
 808         first = evlist__first(session->evlist);
 809         jd.sample_type = first->core.attr.sample_type;
 810
 811         *nbytes = 0;
 812
 813         ret = jit_inject(&jd, filename);
 814         if (!ret) {
 815                 jit_add_pid(machine, pid);
 816                 *nbytes = jd.bytes_written;
 817                 ret = 1;
 818         }
 819
 820         return ret;
 821 }