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 #include <sys/utsname.h>
   7 #ifdef HAVE_BACKTRACE_SUPPORT
   8 #include <execinfo.h>
   9 #endif
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <string.h>
  13 #include <errno.h>
  14 #include <limits.h>
  15 #include <byteswap.h>
  16 #include <linux/kernel.h>
  17 #include <unistd.h>
  18 #include "callchain.h"
  19 #include "strlist.h"
  20
  21 struct callchain_param  callchain_param = {
  22         .mode   = CHAIN_GRAPH_ABS,
  23         .min_percent = 0.5,
  24         .order  = ORDER_CALLEE,
  25         .key    = CCKEY_FUNCTION,
  26         .value  = CCVAL_PERCENT,
  27 };
  28
  29 /*
  30  * XXX We need to find a better place for these things...
  31  */
  32 unsigned int page_size;
  33 int cacheline_size;
  34
  35 bool test_attr__enabled;
  36
  37 bool perf_host  = true;
  38 bool perf_guest = false;
  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         signal(sig, SIG_DFL);
 357         raise(sig);
 358 }
 359
 360 int parse_nsec_time(const char *str, u64 *ptime)
 361 {
 362         u64 time_sec, time_nsec;
 363         char *end;
 364
 365         time_sec = strtoul(str, &end, 10);
 366         if (*end != '.' && *end != '\0')
 367                 return -1;
 368
 369         if (*end == '.') {
 370                 int i;
 371                 char nsec_buf[10];
 372
 373                 if (strlen(++end) > 9)
 374                         return -1;
 375
 376                 strncpy(nsec_buf, end, 9);
 377                 nsec_buf[9] = '\0';
 378
 379                 /* make it nsec precision */
 380                 for (i = strlen(nsec_buf); i < 9; i++)
 381                         nsec_buf[i] = '0';
 382
 383                 time_nsec = strtoul(nsec_buf, &end, 10);
 384                 if (*end != '\0')
 385                         return -1;
 386         } else
 387                 time_nsec = 0;
 388
 389         *ptime = time_sec * NSEC_PER_SEC + time_nsec;
 390         return 0;
 391 }
 392
 393 unsigned long parse_tag_value(const char *str, struct parse_tag *tags)
 394 {
 395         struct parse_tag *i = tags;
 396
 397         while (i->tag) {
 398                 char *s;
 399
 400                 s = strchr(str, i->tag);
 401                 if (s) {
 402                         unsigned long int value;
 403                         char *endptr;
 404
 405                         value = strtoul(str, &endptr, 10);
 406                         if (s != endptr)
 407                                 break;
 408
 409                         if (value > ULONG_MAX / i->mult)
 410                                 break;
 411                         value *= i->mult;
 412                         return value;
 413                 }
 414                 i++;
 415         }
 416
 417         return (unsigned long) -1;
 418 }
 419
 420 int get_stack_size(const char *str, unsigned long *_size)
 421 {
 422         char *endptr;
 423         unsigned long size;
 424         unsigned long max_size = round_down(USHRT_MAX, sizeof(u64));
 425
 426         size = strtoul(str, &endptr, 0);
 427
 428         do {
 429                 if (*endptr)
 430                         break;
 431
 432                 size = round_up(size, sizeof(u64));
 433                 if (!size || size > max_size)
 434                         break;
 435
 436                 *_size = size;
 437                 return 0;
 438
 439         } while (0);
 440
 441         pr_err("callchain: Incorrect stack dump size (max %ld): %s\n",
 442                max_size, str);
 443         return -1;
 444 }
 445
 446 int parse_callchain_record(const char *arg, struct callchain_param *param)
 447 {
 448         char *tok, *name, *saveptr = NULL;
 449         char *buf;
 450         int ret = -1;
 451
 452         /* We need buffer that we know we can write to. */
 453         buf = malloc(strlen(arg) + 1);
 454         if (!buf)
 455                 return -ENOMEM;
 456
 457         strcpy(buf, arg);
 458
 459         tok = strtok_r((char *)buf, ",", &saveptr);
 460         name = tok ? : (char *)buf;
 461
 462         do {
 463                 /* Framepointer style */
 464                 if (!strncmp(name, "fp", sizeof("fp"))) {
 465                         if (!strtok_r(NULL, ",", &saveptr)) {
 466                                 param->record_mode = CALLCHAIN_FP;
 467                                 ret = 0;
 468                         } else
 469                                 pr_err("callchain: No more arguments "
 470                                        "needed for --call-graph fp\n");
 471                         break;
 472
 473 #ifdef HAVE_DWARF_UNWIND_SUPPORT
 474                 /* Dwarf style */
 475                 } else if (!strncmp(name, "dwarf", sizeof("dwarf"))) {
 476                         const unsigned long default_stack_dump_size = 8192;
 477
 478                         ret = 0;
 479                         param->record_mode = CALLCHAIN_DWARF;
 480                         param->dump_size = default_stack_dump_size;
 481
 482                         tok = strtok_r(NULL, ",", &saveptr);
 483                         if (tok) {
 484                                 unsigned long size = 0;
 485
 486                                 ret = get_stack_size(tok, &size);
 487                                 param->dump_size = size;
 488                         }
 489 #endif /* HAVE_DWARF_UNWIND_SUPPORT */
 490                 } else if (!strncmp(name, "lbr", sizeof("lbr"))) {
 491                         if (!strtok_r(NULL, ",", &saveptr)) {
 492                                 param->record_mode = CALLCHAIN_LBR;
 493                                 ret = 0;
 494                         } else
 495                                 pr_err("callchain: No more arguments "
 496                                         "needed for --call-graph lbr\n");
 497                         break;
 498                 } else {
 499                         pr_err("callchain: Unknown --call-graph option "
 500                                "value: %s\n", arg);
 501                         break;
 502                 }
 503
 504         } while (0);
 505
 506         free(buf);
 507         return ret;
 508 }
 509
 510 int filename__read_str(const char *filename, char **buf, size_t *sizep)
 511 {
 512         size_t size = 0, alloc_size = 0;
 513         void *bf = NULL, *nbf;
 514         int fd, n, err = 0;
 515         char sbuf[STRERR_BUFSIZE];
 516
 517         fd = open(filename, O_RDONLY);
 518         if (fd < 0)
 519                 return -errno;
 520
 521         do {
 522                 if (size == alloc_size) {
 523                         alloc_size += BUFSIZ;
 524                         nbf = realloc(bf, alloc_size);
 525                         if (!nbf) {
 526                                 err = -ENOMEM;
 527                                 break;
 528                         }
 529
 530                         bf = nbf;
 531                 }
 532
 533                 n = read(fd, bf + size, alloc_size - size);
 534                 if (n < 0) {
 535                         if (size) {
 536                                 pr_warning("read failed %d: %s\n", errno,
 537                                          strerror_r(errno, sbuf, sizeof(sbuf)));
 538                                 err = 0;
 539                         } else
 540                                 err = -errno;
 541
 542                         break;
 543                 }
 544
 545                 size += n;
 546         } while (n > 0);
 547
 548         if (!err) {
 549                 *sizep = size;
 550                 *buf   = bf;
 551         } else
 552                 free(bf);
 553
 554         close(fd);
 555         return err;
 556 }
 557
 558 const char *get_filename_for_perf_kvm(void)
 559 {
 560         const char *filename;
 561
 562         if (perf_host && !perf_guest)
 563                 filename = strdup("perf.data.host");
 564         else if (!perf_host && perf_guest)
 565                 filename = strdup("perf.data.guest");
 566         else
 567                 filename = strdup("perf.data.kvm");
 568
 569         return filename;
 570 }
 571
 572 int perf_event_paranoid(void)
 573 {
 574         int value;
 575
 576         if (sysctl__read_int("kernel/perf_event_paranoid", &value))
 577                 return INT_MAX;
 578
 579         return value;
 580 }
 581
 582 void mem_bswap_32(void *src, int byte_size)
 583 {
 584         u32 *m = src;
 585         while (byte_size > 0) {
 586                 *m = bswap_32(*m);
 587                 byte_size -= sizeof(u32);
 588                 ++m;
 589         }
 590 }
 591
 592 void mem_bswap_64(void *src, int byte_size)
 593 {
 594         u64 *m = src;
 595
 596         while (byte_size > 0) {
 597                 *m = bswap_64(*m);
 598                 byte_size -= sizeof(u64);
 599                 ++m;
 600         }
 601 }
 602
 603 bool find_process(const char *name)
 604 {
 605         size_t len = strlen(name);
 606         DIR *dir;
 607         struct dirent *d;
 608         int ret = -1;
 609
 610         dir = opendir(procfs__mountpoint());
 611         if (!dir)
 612                 return false;
 613
 614         /* Walk through the directory. */
 615         while (ret && (d = readdir(dir)) != NULL) {
 616                 char path[PATH_MAX];
 617                 char *data;
 618                 size_t size;
 619
 620                 if ((d->d_type != DT_DIR) ||
 621                      !strcmp(".", d->d_name) ||
 622                      !strcmp("..", d->d_name))
 623                         continue;
 624
 625                 scnprintf(path, sizeof(path), "%s/%s/comm",
 626                           procfs__mountpoint(), d->d_name);
 627
 628                 if (filename__read_str(path, &data, &size))
 629                         continue;
 630
 631                 ret = strncmp(name, data, len);
 632                 free(data);
 633         }
 634
 635         closedir(dir);
 636         return ret ? false : true;
 637 }
 638
 639 int
 640 fetch_kernel_version(unsigned int *puint, char *str,
 641                      size_t str_size)
 642 {
 643         struct utsname utsname;
 644         int version, patchlevel, sublevel, err;
 645
 646         if (uname(&utsname))
 647                 return -1;
 648
 649         if (str && str_size) {
 650                 strncpy(str, utsname.release, str_size);
 651                 str[str_size - 1] = '\0';
 652         }
 653
 654         err = sscanf(utsname.release, "%d.%d.%d",
 655                      &version, &patchlevel, &sublevel);
 656
 657         if (err != 3) {
 658                 pr_debug("Unablt to get kernel version from uname '%s'\n",
 659                          utsname.release);
 660                 return -1;
 661         }
 662
 663         if (puint)
 664                 *puint = (version << 16) + (patchlevel << 8) + sublevel;
 665         return 0;
 666 }
 667
 668 const char *perf_tip(const char *dirpath)
 669 {
 670         struct strlist *tips;
 671         struct str_node *node;
 672         char *tip = NULL;
 673         struct strlist_config conf = {
 674                 .dirname = dirpath,
 675                 .file_only = true,
 676         };
 677
 678         tips = strlist__new("tips.txt", &conf);
 679         if (tips == NULL)
 680                 return errno == ENOENT ? NULL : "Tip: get more memory! ;-p";
 681
 682         if (strlist__nr_entries(tips) == 0)
 683                 goto out;
 684
 685         node = strlist__entry(tips, random() % strlist__nr_entries(tips));
 686         if (asprintf(&tip, "Tip: %s", node->s) < 0)
 687                 tip = (char *)"Tip: get more memory! ;-)";
 688
 689 out:
 690         strlist__delete(tips);
 691
 692         return tip;
 693 }