tools/perf/util/util.c

   1 #include "../perf.h"
   2 #include "util.h"
   3 #include "debug.h"
   4 #include <api/fs/fs.h>
   5 #include <sys/mman.h>
   6 #ifdef HAVE_BACKTRACE_SUPPORT
   7 #include <execinfo.h>
   8 #endif
   9 #include <stdio.h>
  10 #include <stdlib.h>
  11 #include <string.h>
  12 #include <errno.h>
  13 #include <limits.h>
  14 #include <byteswap.h>
  15 #include <linux/kernel.h>
  16 #include <unistd.h>
  17 #include "callchain.h"
  18
  19 struct callchain_param  callchain_param = {
  20         .mode   = CHAIN_GRAPH_REL,
  21         .min_percent = 0.5,
  22         .order  = ORDER_CALLEE,
  23         .key    = CCKEY_FUNCTION
  24 };
  25
  26 /*
  27  * XXX We need to find a better place for these things...
  28  */
  29 unsigned int page_size;
  30 int cacheline_size;
  31
  32 bool test_attr__enabled;
  33
  34 bool perf_host  = true;
  35 bool perf_guest = false;
  36
  37 char tracing_path[PATH_MAX + 1]        = "/sys/kernel/debug/tracing";
  38 char tracing_events_path[PATH_MAX + 1] = "/sys/kernel/debug/tracing/events";
  39
  40 void event_attr_init(struct perf_event_attr *attr)
  41 {
  42         if (!perf_host)
  43                 attr->exclude_host  = 1;
  44         if (!perf_guest)
  45                 attr->exclude_guest = 1;
  46         /* to capture ABI version */
  47         attr->size = sizeof(*attr);
  48 }
  49
  50 int mkdir_p(char *path, mode_t mode)
  51 {
  52         struct stat st;
  53         int err;
  54         char *d = path;
  55
  56         if (*d != '/')
  57                 return -1;
  58
  59         if (stat(path, &st) == 0)
  60                 return 0;
  61
  62         while (*++d == '/');
  63
  64         while ((d = strchr(d, '/'))) {
  65                 *d = '\0';
  66                 err = stat(path, &st) && mkdir(path, mode);
  67                 *d++ = '/';
  68                 if (err)
  69                         return -1;
  70                 while (*d == '/')
  71                         ++d;
  72         }
  73         return (stat(path, &st) && mkdir(path, mode)) ? -1 : 0;
  74 }
  75
  76 int rm_rf(char *path)
  77 {
  78         DIR *dir;
  79         int ret = 0;
  80         struct dirent *d;
  81         char namebuf[PATH_MAX];
  82
  83         dir = opendir(path);
  84         if (dir == NULL)
  85                 return 0;
  86
  87         while ((d = readdir(dir)) != NULL && !ret) {
  88                 struct stat statbuf;
  89
  90                 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
  91                         continue;
  92
  93                 scnprintf(namebuf, sizeof(namebuf), "%s/%s",
  94                           path, d->d_name);
  95
  96                 ret = stat(namebuf, &statbuf);
  97                 if (ret < 0) {
  98                         pr_debug("stat failed: %s\n", namebuf);
  99                         break;
 100                 }
 101
 102                 if (S_ISREG(statbuf.st_mode))
 103                         ret = unlink(namebuf);
 104                 else if (S_ISDIR(statbuf.st_mode))
 105                         ret = rm_rf(namebuf);
 106                 else {
 107                         pr_debug("unknown file: %s\n", namebuf);
 108                         ret = -1;
 109                 }
 110         }
 111         closedir(dir);
 112
 113         if (ret < 0)
 114                 return ret;
 115
 116         return rmdir(path);
 117 }
 118
 119 static int slow_copyfile(const char *from, const char *to)
 120 {
 121         int err = -1;
 122         char *line = NULL;
 123         size_t n;
 124         FILE *from_fp = fopen(from, "r"), *to_fp;
 125
 126         if (from_fp == NULL)
 127                 goto out;
 128
 129         to_fp = fopen(to, "w");
 130         if (to_fp == NULL)
 131                 goto out_fclose_from;
 132
 133         while (getline(&line, &n, from_fp) > 0)
 134                 if (fputs(line, to_fp) == EOF)
 135                         goto out_fclose_to;
 136         err = 0;
 137 out_fclose_to:
 138         fclose(to_fp);
 139         free(line);
 140 out_fclose_from:
 141         fclose(from_fp);
 142 out:
 143         return err;
 144 }
 145
 146 int copyfile_offset(int ifd, loff_t off_in, int ofd, loff_t off_out, u64 size)
 147 {
 148         void *ptr;
 149         loff_t pgoff;
 150
 151         pgoff = off_in & ~(page_size - 1);
 152         off_in -= pgoff;
 153
 154         ptr = mmap(NULL, off_in + size, PROT_READ, MAP_PRIVATE, ifd, pgoff);
 155         if (ptr == MAP_FAILED)
 156                 return -1;
 157
 158         while (size) {
 159                 ssize_t ret = pwrite(ofd, ptr + off_in, size, off_out);
 160                 if (ret < 0 && errno == EINTR)
 161                         continue;
 162                 if (ret <= 0)
 163                         break;
 164
 165                 size -= ret;
 166                 off_in += ret;
 167                 off_out -= ret;
 168         }
 169         munmap(ptr, off_in + size);
 170
 171         return size ? -1 : 0;
 172 }
 173
 174 int copyfile_mode(const char *from, const char *to, mode_t mode)
 175 {
 176         int fromfd, tofd;
 177         struct stat st;
 178         int err = -1;
 179         char *tmp = NULL, *ptr = NULL;
 180
 181         if (stat(from, &st))
 182                 goto out;
 183
 184         /* extra 'x' at the end is to reserve space for '.' */
 185         if (asprintf(&tmp, "%s.XXXXXXx", to) < 0) {
 186                 tmp = NULL;
 187                 goto out;
 188         }
 189         ptr = strrchr(tmp, '/');
 190         if (!ptr)
 191                 goto out;
 192         ptr = memmove(ptr + 1, ptr, strlen(ptr) - 1);
 193         *ptr = '.';
 194
 195         tofd = mkstemp(tmp);
 196         if (tofd < 0)
 197                 goto out;
 198
 199         if (fchmod(tofd, mode))
 200                 goto out_close_to;
 201
 202         if (st.st_size == 0) { /* /proc? do it slowly... */
 203                 err = slow_copyfile(from, tmp);
 204                 goto out_close_to;
 205         }
 206
 207         fromfd = open(from, O_RDONLY);
 208         if (fromfd < 0)
 209                 goto out_close_to;
 210
 211         err = copyfile_offset(fromfd, 0, tofd, 0, st.st_size);
 212
 213         close(fromfd);
 214 out_close_to:
 215         close(tofd);
 216         if (!err)
 217                 err = link(tmp, to);
 218         unlink(tmp);
 219 out:
 220         free(tmp);
 221         return err;
 222 }
 223
 224 int copyfile(const char *from, const char *to)
 225 {
 226         return copyfile_mode(from, to, 0755);
 227 }
 228
 229 unsigned long convert_unit(unsigned long value, char *unit)
 230 {
 231         *unit = ' ';
 232
 233         if (value > 1000) {
 234                 value /= 1000;
 235                 *unit = 'K';
 236         }
 237
 238         if (value > 1000) {
 239                 value /= 1000;
 240                 *unit = 'M';
 241         }
 242
 243         if (value > 1000) {
 244                 value /= 1000;
 245                 *unit = 'G';
 246         }
 247
 248         return value;
 249 }
 250
 251 static ssize_t ion(bool is_read, int fd, void *buf, size_t n)
 252 {
 253         void *buf_start = buf;
 254         size_t left = n;
 255
 256         while (left) {
 257                 ssize_t ret = is_read ? read(fd, buf, left) :
 258                                         write(fd, buf, left);
 259
 260                 if (ret < 0 && errno == EINTR)
 261                         continue;
 262                 if (ret <= 0)
 263                         return ret;
 264
 265                 left -= ret;
 266                 buf  += ret;
 267         }
 268
 269         BUG_ON((size_t)(buf - buf_start) != n);
 270         return n;
 271 }
 272
 273 /*
 274  * Read exactly 'n' bytes or return an error.
 275  */
 276 ssize_t readn(int fd, void *buf, size_t n)
 277 {
 278         return ion(true, fd, buf, n);
 279 }
 280
 281 /*
 282  * Write exactly 'n' bytes or return an error.
 283  */
 284 ssize_t writen(int fd, void *buf, size_t n)
 285 {
 286         return ion(false, fd, buf, n);
 287 }
 288
 289 size_t hex_width(u64 v)
 290 {
 291         size_t n = 1;
 292
 293         while ((v >>= 4))
 294                 ++n;
 295
 296         return n;
 297 }
 298
 299 static int hex(char ch)
 300 {
 301         if ((ch >= '0') && (ch <= '9'))
 302                 return ch - '0';
 303         if ((ch >= 'a') && (ch <= 'f'))
 304                 return ch - 'a' + 10;
 305         if ((ch >= 'A') && (ch <= 'F'))
 306                 return ch - 'A' + 10;
 307         return -1;
 308 }
 309
 310 /*
 311  * While we find nice hex chars, build a long_val.
 312  * Return number of chars processed.
 313  */
 314 int hex2u64(const char *ptr, u64 *long_val)
 315 {
 316         const char *p = ptr;
 317         *long_val = 0;
 318
 319         while (*p) {
 320                 const int hex_val = hex(*p);
 321
 322                 if (hex_val < 0)
 323                         break;
 324
 325                 *long_val = (*long_val << 4) | hex_val;
 326                 p++;
 327         }
 328
 329         return p - ptr;
 330 }
 331
 332 /* Obtain a backtrace and print it to stdout. */
 333 #ifdef HAVE_BACKTRACE_SUPPORT
 334 void dump_stack(void)
 335 {
 336         void *array[16];
 337         size_t size = backtrace(array, ARRAY_SIZE(array));
 338         char **strings = backtrace_symbols(array, size);
 339         size_t i;
 340
 341         printf("Obtained %zd stack frames.\n", size);
 342
 343         for (i = 0; i < size; i++)
 344                 printf("%s\n", strings[i]);
 345
 346         free(strings);
 347 }
 348 #else
 349 void dump_stack(void) {}
 350 #endif
 351
 352 void sighandler_dump_stack(int sig)
 353 {
 354         psignal(sig, "perf");
 355         dump_stack();
 356         exit(sig);
 357 }
 358
 359 void get_term_dimensions(struct winsize *ws)
 360 {
 361         char *s = getenv("LINES");
 362
 363         if (s != NULL) {
 364                 ws->ws_row = atoi(s);
 365                 s = getenv("COLUMNS");
 366                 if (s != NULL) {
 367                         ws->ws_col = atoi(s);
 368                         if (ws->ws_row && ws->ws_col)
 369                                 return;
 370                 }
 371         }
 372 #ifdef TIOCGWINSZ
 373         if (ioctl(1, TIOCGWINSZ, ws) == 0 &&
 374             ws->ws_row && ws->ws_col)
 375                 return;
 376 #endif
 377         ws->ws_row = 25;
 378         ws->ws_col = 80;
 379 }
 380
 381 void set_term_quiet_input(struct termios *old)
 382 {
 383         struct termios tc;
 384
 385         tcgetattr(0, old);
 386         tc = *old;
 387         tc.c_lflag &= ~(ICANON | ECHO);
 388         tc.c_cc[VMIN] = 0;
 389         tc.c_cc[VTIME] = 0;
 390         tcsetattr(0, TCSANOW, &tc);
 391 }
 392
 393 static void set_tracing_events_path(const char *tracing, const char *mountpoint)
 394 {
 395         snprintf(tracing_path, sizeof(tracing_path), "%s/%s",
 396                  mountpoint, tracing);
 397         snprintf(tracing_events_path, sizeof(tracing_events_path), "%s/%s%s",
 398                  mountpoint, tracing, "events");
 399 }
 400
 401 static const char *__perf_tracefs_mount(const char *mountpoint)
 402 {
 403         const char *mnt;
 404
 405         mnt = tracefs_mount(mountpoint);
 406         if (!mnt)
 407                 return NULL;
 408
 409         set_tracing_events_path("", mnt);
 410
 411         return mnt;
 412 }
 413
 414 static const char *__perf_debugfs_mount(const char *mountpoint)
 415 {
 416         const char *mnt;
 417
 418         mnt = debugfs_mount(mountpoint);
 419         if (!mnt)
 420                 return NULL;
 421
 422         set_tracing_events_path("tracing/", mnt);
 423
 424         return mnt;
 425 }
 426
 427 const char *perf_debugfs_mount(const char *mountpoint)
 428 {
 429         const char *mnt;
 430
 431         mnt = __perf_tracefs_mount(mountpoint);
 432         if (mnt)
 433                 return mnt;
 434
 435         mnt = __perf_debugfs_mount(mountpoint);
 436
 437         return mnt;
 438 }
 439
 440 void perf_debugfs_set_path(const char *mntpt)
 441 {
 442         set_tracing_events_path("tracing/", mntpt);
 443 }
 444
 445 char *get_tracing_file(const char *name)
 446 {
 447         char *file;
 448
 449         if (asprintf(&file, "%s/%s", tracing_path, name) < 0)
 450                 return NULL;
 451
 452         return file;
 453 }
 454
 455 void put_tracing_file(char *file)
 456 {
 457         free(file);
 458 }
 459
 460 int parse_nsec_time(const char *str, u64 *ptime)
 461 {
 462         u64 time_sec, time_nsec;
 463         char *end;
 464
 465         time_sec = strtoul(str, &end, 10);
 466         if (*end != '.' && *end != '\0')
 467                 return -1;
 468
 469         if (*end == '.') {
 470                 int i;
 471                 char nsec_buf[10];
 472
 473                 if (strlen(++end) > 9)
 474                         return -1;
 475
 476                 strncpy(nsec_buf, end, 9);
 477                 nsec_buf[9] = '\0';
 478
 479                 /* make it nsec precision */
 480                 for (i = strlen(nsec_buf); i < 9; i++)
 481                         nsec_buf[i] = '0';
 482
 483                 time_nsec = strtoul(nsec_buf, &end, 10);
 484                 if (*end != '\0')
 485                         return -1;
 486         } else
 487                 time_nsec = 0;
 488
 489         *ptime = time_sec * NSEC_PER_SEC + time_nsec;
 490         return 0;
 491 }
 492
 493 unsigned long parse_tag_value(const char *str, struct parse_tag *tags)
 494 {
 495         struct parse_tag *i = tags;
 496
 497         while (i->tag) {
 498                 char *s;
 499
 500                 s = strchr(str, i->tag);
 501                 if (s) {
 502                         unsigned long int value;
 503                         char *endptr;
 504
 505                         value = strtoul(str, &endptr, 10);
 506                         if (s != endptr)
 507                                 break;
 508
 509                         if (value > ULONG_MAX / i->mult)
 510                                 break;
 511                         value *= i->mult;
 512                         return value;
 513                 }
 514                 i++;
 515         }
 516
 517         return (unsigned long) -1;
 518 }
 519
 520 int get_stack_size(const char *str, unsigned long *_size)
 521 {
 522         char *endptr;
 523         unsigned long size;
 524         unsigned long max_size = round_down(USHRT_MAX, sizeof(u64));
 525
 526         size = strtoul(str, &endptr, 0);
 527
 528         do {
 529                 if (*endptr)
 530                         break;
 531
 532                 size = round_up(size, sizeof(u64));
 533                 if (!size || size > max_size)
 534                         break;
 535
 536                 *_size = size;
 537                 return 0;
 538
 539         } while (0);
 540
 541         pr_err("callchain: Incorrect stack dump size (max %ld): %s\n",
 542                max_size, str);
 543         return -1;
 544 }
 545
 546 int parse_callchain_record(const char *arg, struct callchain_param *param)
 547 {
 548         char *tok, *name, *saveptr = NULL;
 549         char *buf;
 550         int ret = -1;
 551
 552         /* We need buffer that we know we can write to. */
 553         buf = malloc(strlen(arg) + 1);
 554         if (!buf)
 555                 return -ENOMEM;
 556
 557         strcpy(buf, arg);
 558
 559         tok = strtok_r((char *)buf, ",", &saveptr);
 560         name = tok ? : (char *)buf;
 561
 562         do {
 563                 /* Framepointer style */
 564                 if (!strncmp(name, "fp", sizeof("fp"))) {
 565                         if (!strtok_r(NULL, ",", &saveptr)) {
 566                                 param->record_mode = CALLCHAIN_FP;
 567                                 ret = 0;
 568                         } else
 569                                 pr_err("callchain: No more arguments "
 570                                        "needed for --call-graph fp\n");
 571                         break;
 572
 573 #ifdef HAVE_DWARF_UNWIND_SUPPORT
 574                 /* Dwarf style */
 575                 } else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
 576                         const unsigned long default_stack_dump_size = 8192;
 577
 578                         ret = 0;
 579                         param->record_mode = CALLCHAIN_DWARF;
 580                         param->dump_size = default_stack_dump_size;
 581
 582                         tok = strtok_r(NULL, ",", &saveptr);
 583                         if (tok) {
 584                                 unsigned long size = 0;
 585
 586                                 ret = get_stack_size(tok, &size);
 587                                 param->dump_size = size;
 588                         }
 589 #endif /* HAVE_DWARF_UNWIND_SUPPORT */
 590                 } else if (!strncmp(name, "lbr", sizeof("lbr"))) {
 591                         if (!strtok_r(NULL, ",", &saveptr)) {
 592                                 param->record_mode = CALLCHAIN_LBR;
 593                                 ret = 0;
 594                         } else
 595                                 pr_err("callchain: No more arguments "
 596                                         "needed for --call-graph lbr\n");
 597                         break;
 598                 } else {
 599                         pr_err("callchain: Unknown --call-graph option "
 600                                "value: %s\n", arg);
 601                         break;
 602                 }
 603
 604         } while (0);
 605
 606         free(buf);
 607         return ret;
 608 }
 609
 610 int filename__read_str(const char *filename, char **buf, size_t *sizep)
 611 {
 612         size_t size = 0, alloc_size = 0;
 613         void *bf = NULL, *nbf;
 614         int fd, n, err = 0;
 615         char sbuf[STRERR_BUFSIZE];
 616
 617         fd = open(filename, O_RDONLY);
 618         if (fd < 0)
 619                 return -errno;
 620
 621         do {
 622                 if (size == alloc_size) {
 623                         alloc_size += BUFSIZ;
 624                         nbf = realloc(bf, alloc_size);
 625                         if (!nbf) {
 626                                 err = -ENOMEM;
 627                                 break;
 628                         }
 629
 630                         bf = nbf;
 631                 }
 632
 633                 n = read(fd, bf + size, alloc_size - size);
 634                 if (n < 0) {
 635                         if (size) {
 636                                 pr_warning("read failed %d: %s\n", errno,
 637                                          strerror_r(errno, sbuf, sizeof(sbuf)));
 638                                 err = 0;
 639                         } else
 640                                 err = -errno;
 641
 642                         break;
 643                 }
 644
 645                 size += n;
 646         } while (n > 0);
 647
 648         if (!err) {
 649                 *sizep = size;
 650                 *buf   = bf;
 651         } else
 652                 free(bf);
 653
 654         close(fd);
 655         return err;
 656 }
 657
 658 const char *get_filename_for_perf_kvm(void)
 659 {
 660         const char *filename;
 661
 662         if (perf_host && !perf_guest)
 663                 filename = strdup("perf.data.host");
 664         else if (!perf_host && perf_guest)
 665                 filename = strdup("perf.data.guest");
 666         else
 667                 filename = strdup("perf.data.kvm");
 668
 669         return filename;
 670 }
 671
 672 int perf_event_paranoid(void)
 673 {
 674         int value;
 675
 676         if (sysctl__read_int("kernel/perf_event_paranoid", &value))
 677                 return INT_MAX;
 678
 679         return value;
 680 }
 681
 682 void mem_bswap_32(void *src, int byte_size)
 683 {
 684         u32 *m = src;
 685         while (byte_size > 0) {
 686                 *m = bswap_32(*m);
 687                 byte_size -= sizeof(u32);
 688                 ++m;
 689         }
 690 }
 691
 692 void mem_bswap_64(void *src, int byte_size)
 693 {
 694         u64 *m = src;
 695
 696         while (byte_size > 0) {
 697                 *m = bswap_64(*m);
 698                 byte_size -= sizeof(u64);
 699                 ++m;
 700         }
 701 }
 702
 703 bool find_process(const char *name)
 704 {
 705         size_t len = strlen(name);
 706         DIR *dir;
 707         struct dirent *d;
 708         int ret = -1;
 709
 710         dir = opendir(procfs__mountpoint());
 711         if (!dir)
 712                 return -1;
 713
 714         /* Walk through the directory. */
 715         while (ret && (d = readdir(dir)) != NULL) {
 716                 char path[PATH_MAX];
 717                 char *data;
 718                 size_t size;
 719
 720                 if ((d->d_type != DT_DIR) ||
 721                      !strcmp(".", d->d_name) ||
 722                      !strcmp("..", d->d_name))
 723                         continue;
 724
 725                 scnprintf(path, sizeof(path), "%s/%s/comm",
 726                           procfs__mountpoint(), d->d_name);
 727
 728                 if (filename__read_str(path, &data, &size))
 729                         continue;
 730
 731                 ret = strncmp(name, data, len);
 732                 free(data);
 733         }
 734
 735         closedir(dir);
 736         return ret ? false : true;
 737 }