sys-utils/readprofile.c

   1 /*
   2  * SPDX-License-Identifier: GPL-2.0-or-later
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * Copyright (C) 1994,1996 Alessandro Rubini (rubini@ipvvis.unipv.it)
  10  *
  11  * readprofile.c - used to read /proc/profile
  12  */
  13
  14 /*
  15  * 1999-02-22 Arkadiusz Miśkiewicz <misiek@pld.ORG.PL>
  16  * - added Native Language Support
  17  * 1999-09-01 Stephane Eranian <eranian@cello.hpl.hp.com>
  18  * - 64bit clean patch
  19  * 3Feb2001 Andrew Morton <andrewm@uow.edu.au>
  20  * - -M option to write profile multiplier.
  21  * 2001-11-07 Werner Almesberger <wa@almesberger.net>
  22  * - byte order auto-detection and -n option
  23  * 2001-11-09 Werner Almesberger <wa@almesberger.net>
  24  * - skip step size (index 0)
  25  * 2002-03-09 John Levon <moz@compsoc.man.ac.uk>
  26  * - make maplineno do something
  27  * 2002-11-28 Mads Martin Joergensen +
  28  * - also try /boot/System.map-`uname -r`
  29  * 2003-04-09 Werner Almesberger <wa@almesberger.net>
  30  * - fixed off-by eight error and improved heuristics in byte order detection
  31  * 2003-08-12 Nikita Danilov <Nikita@Namesys.COM>
  32  * - added -s option; example of use:
  33  * "readprofile -s -m /boot/System.map-test | grep __d_lookup | sort -n -k3"
  34  */
  35
  36 #include <errno.h>
  37 #include <fcntl.h>
  38 #include <getopt.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42 #include <sys/stat.h>
  43 #include <sys/types.h>
  44 #include <sys/utsname.h>
  45 #include <unistd.h>
  46
  47 #include "c.h"
  48 #include "strutils.h"
  49 #include "nls.h"
  50 #include "xalloc.h"
  51 #include "closestream.h"
  52
  53 #define S_LEN 128
  54
  55 /* These are the defaults */
  56 static char defaultmap[]="/boot/System.map";
  57 static char defaultpro[]="/proc/profile";
  58
  59 static FILE *myopen(char *name, char *mode, int *flag)
  60 {
  61         int len = strlen(name);
  62
  63         if (!strcmp(name + len - 3, ".gz")) {
  64                 FILE *res;
  65                 char *cmdline = xmalloc(len + 6);
  66                 snprintf(cmdline, len + 6, "zcat %s", name);
  67                 res = popen(cmdline, mode);
  68                 free(cmdline);
  69                 *flag = 1;
  70                 return res;
  71         }
  72         *flag = 0;
  73         return fopen(name, mode);
  74 }
  75
  76 #ifndef BOOT_SYSTEM_MAP
  77 #define BOOT_SYSTEM_MAP "/boot/System.map-"
  78 #endif
  79
  80 static char *boot_uname_r_str(void)
  81 {
  82         struct utsname uname_info;
  83         char *s;
  84
  85         if (uname(&uname_info))
  86                 return "";
  87         xasprintf(&s, "%s%s", BOOT_SYSTEM_MAP, uname_info.release);
  88         return s;
  89 }
  90
  91 static void __attribute__((__noreturn__)) usage(void)
  92 {
  93         FILE *out = stdout;
  94         fputs(USAGE_HEADER, out);
  95         fprintf(out, _(" %s [options]\n"), program_invocation_short_name);
  96
  97         fputs(USAGE_SEPARATOR, out);
  98         fputs(_("Display kernel profiling information.\n"), out);
  99
 100         fputs(USAGE_OPTIONS, out);
 101         fprintf(out,
 102               _(" -m, --mapfile <mapfile>   (defaults: \"%s\" and\n"), defaultmap);
 103         fprintf(out,
 104               _("                                      \"%s\")\n"), boot_uname_r_str());
 105         fprintf(out,
 106               _(" -p, --profile <pro-file>  (default:  \"%s\")\n"), defaultpro);
 107         fputs(_(" -M, --multiplier <mult>   set the profiling multiplier to <mult>\n"), out);
 108         fputs(_(" -i, --info                print only info about the sampling step\n"), out);
 109         fputs(_(" -v, --verbose             print verbose data\n"), out);
 110         fputs(_(" -a, --all                 print all symbols, even if count is 0\n"), out);
 111         fputs(_(" -b, --histbin             print individual histogram-bin counts\n"), out);
 112         fputs(_(" -s, --counters            print individual counters within functions\n"), out);
 113         fputs(_(" -r, --reset               reset all the counters (root only)\n"), out);
 114         fputs(_(" -n, --no-auto             disable byte order auto-detection\n"), out);
 115         fputs(USAGE_SEPARATOR, out);
 116         fprintf(out, USAGE_HELP_OPTIONS(27));
 117         fprintf(out, USAGE_MAN_TAIL("readprofile(8)"));
 118         exit(EXIT_SUCCESS);
 119 }
 120
 121 int main(int argc, char **argv)
 122 {
 123         FILE *map;
 124         int proFd, has_mult = 0, multiplier = 0;
 125         char *mapFile, *proFile;
 126         size_t len = 0, indx = 1;
 127         unsigned long long add0 = 0;
 128         unsigned int step;
 129         unsigned int *buf, total, fn_len;
 130         unsigned long long fn_add = 0, next_add; /* current and next address */
 131         char fn_name[S_LEN], next_name[S_LEN];  /* current and next name */
 132         char mode[8];
 133         int c;
 134         ssize_t rc;
 135         int optAll = 0, optInfo = 0, optReset = 0, optVerbose = 0, optNative = 0;
 136         int optBins = 0, optSub = 0;
 137         char mapline[S_LEN];
 138         int maplineno = 1;
 139         int popenMap;           /* flag to tell if popen() has been used */
 140         int header_printed;
 141         double rep = 0;
 142
 143         static const struct option longopts[] = {
 144                 {"mapfile", required_argument, NULL, 'm'},
 145                 {"profile", required_argument, NULL, 'p'},
 146                 {"multiplier", required_argument, NULL, 'M'},
 147                 {"info", no_argument, NULL, 'i'},
 148                 {"verbose", no_argument, NULL, 'v'},
 149                 {"all", no_argument, NULL, 'a'},
 150                 {"histbin", no_argument, NULL, 'b'},
 151                 {"counters", no_argument, NULL, 's'},
 152                 {"reset", no_argument, NULL, 'r'},
 153                 {"no-auto", no_argument, NULL, 'n'},
 154                 {"version", no_argument, NULL, 'V'},
 155                 {"help", no_argument, NULL, 'h'},
 156                 {NULL, 0, NULL, 0}
 157         };
 158
 159 #define next (current^1)
 160
 161         setlocale(LC_ALL, "");
 162         bindtextdomain(PACKAGE, LOCALEDIR);
 163         textdomain(PACKAGE);
 164         close_stdout_atexit();
 165
 166         proFile = defaultpro;
 167         mapFile = defaultmap;
 168
 169         while ((c = getopt_long(argc, argv, "m:p:M:ivabsrnVh", longopts, NULL)) != -1) {
 170                 switch (c) {
 171                 case 'm':
 172                         mapFile = optarg;
 173                         break;
 174                 case 'n':
 175                         optNative++;
 176                         break;
 177                 case 'p':
 178                         proFile = optarg;
 179                         break;
 180                 case 'a':
 181                         optAll++;
 182                         break;
 183                 case 'b':
 184                         optBins++;
 185                         break;
 186                 case 's':
 187                         optSub++;
 188                         break;
 189                 case 'i':
 190                         optInfo++;
 191                         break;
 192                 case 'M':
 193                         multiplier = strtol_or_err(optarg, _("failed to parse multiplier"));
 194                         has_mult = 1;
 195                         break;
 196                 case 'r':
 197                         optReset++;
 198                         break;
 199                 case 'v':
 200                         optVerbose++;
 201                         break;
 202
 203                 case 'V':
 204                         print_version(EXIT_SUCCESS);
 205                 case 'h':
 206                         usage();
 207                 default:
 208                         errtryhelp(EXIT_FAILURE);
 209                 }
 210         }
 211
 212         if (optReset || has_mult) {
 213                 int fd, to_write;
 214
 215                 /* When writing the multiplier, if the length of the
 216                  * write is not sizeof(int), the multiplier is not
 217                  * changed. */
 218                 if (has_mult) {
 219                         to_write = sizeof(int);
 220                 } else {
 221                         multiplier = 0;
 222                         /* sth different from sizeof(int) */
 223                         to_write = 1;
 224                 }
 225                 /* try to become root, just in case */
 226                 ignore_result( setuid(0) );
 227                 fd = open(defaultpro, O_WRONLY);
 228                 if (fd < 0)
 229                         err(EXIT_FAILURE, "%s", defaultpro);
 230                 if (write(fd, &multiplier, to_write) != to_write)
 231                         err(EXIT_FAILURE, _("error writing %s"), defaultpro);
 232                 close(fd);
 233                 exit(EXIT_SUCCESS);
 234         }
 235
 236         /* Use an fd for the profiling buffer, to skip stdio overhead */
 237         if (((proFd = open(proFile, O_RDONLY)) < 0)
 238             || ((int)(len = lseek(proFd, 0, SEEK_END)) < 0)
 239             || (lseek(proFd, 0, SEEK_SET) < 0))
 240                 err(EXIT_FAILURE, "%s", proFile);
 241         if (!len)
 242                 errx(EXIT_FAILURE, "%s: %s", proFile, _("input file is empty"));
 243
 244         buf = xmalloc(len);
 245
 246         rc = read(proFd, buf, len);
 247         if (rc < 0 || (size_t) rc != len)
 248                 err(EXIT_FAILURE, "%s", proFile);
 249         close(proFd);
 250
 251         if (!optNative) {
 252                 int entries = len / sizeof(*buf);
 253                 int big = 0, small = 0;
 254                 unsigned *p;
 255                 size_t i;
 256
 257                 for (p = buf + 1; p < buf + entries; p++) {
 258                         if (*p & ~0U << ((unsigned) sizeof(*buf) * 4U))
 259                                 big++;
 260                         if (*p & ((1U << ((unsigned) sizeof(*buf) * 4U)) - 1U))
 261                                 small++;
 262                 }
 263                 if (big > small) {
 264                         warnx(_("Assuming reversed byte order. "
 265                                 "Use -n to force native byte order."));
 266                         for (p = buf; p < buf + entries; p++)
 267                                 for (i = 0; i < sizeof(*buf) / 2; i++) {
 268                                         unsigned char *b = (unsigned char *)p;
 269                                         unsigned char tmp;
 270                                         tmp = b[i];
 271                                         b[i] = b[sizeof(*buf) - i - 1];
 272                                         b[sizeof(*buf) - i - 1] = tmp;
 273                                 }
 274                 }
 275         }
 276
 277         step = buf[0];
 278         if (optInfo) {
 279                 printf(_("Sampling_step: %u\n"), step);
 280                 exit(EXIT_SUCCESS);
 281         }
 282
 283         total = 0;
 284
 285         map = myopen(mapFile, "r", &popenMap);
 286         if (map == NULL && mapFile == defaultmap) {
 287                 mapFile = boot_uname_r_str();
 288                 map = myopen(mapFile, "r", &popenMap);
 289         }
 290         if (map == NULL)
 291                 err(EXIT_FAILURE, "%s", mapFile);
 292
 293         while (fgets(mapline, S_LEN, map)) {
 294                 if (sscanf(mapline, "%llx %7[^\n ] %127[^\n ]", &fn_add, mode, fn_name) != 3)
 295                         errx(EXIT_FAILURE, _("%s(%i): wrong map line"), mapFile,
 296                              maplineno);
 297                 /* only elf works like this */
 298                 if (!strcmp(fn_name, "_stext") || !strcmp(fn_name, "__stext")) {
 299                         add0 = fn_add;
 300                         break;
 301                 }
 302                 maplineno++;
 303         }
 304
 305         if (!add0)
 306                 errx(EXIT_FAILURE, _("can't find \"_stext\" in %s"), mapFile);
 307
 308         /*
 309          * Main loop.
 310          */
 311         while (fgets(mapline, S_LEN, map)) {
 312                 unsigned int this = 0;
 313                 int done = 0;
 314
 315                 if (sscanf(mapline, "%llx %7[^\n ] %127[^\n ]", &next_add, mode, next_name) != 3)
 316                         errx(EXIT_FAILURE, _("%s(%i): wrong map line"), mapFile,
 317                              maplineno);
 318                 header_printed = 0;
 319
 320                 /* the kernel only profiles up to _etext */
 321                 if (!strcmp(next_name, "_etext") ||
 322                     !strcmp(next_name, "__etext"))
 323                         done = 1;
 324                 else {
 325                         /* ignore any LEADING (before a '[tT]' symbol
 326                          * is found) Absolute symbols and __init_end
 327                          * because some architectures place it before
 328                          * .text section */
 329                         if ((*mode == 'A' || *mode == '?')
 330                             && (total == 0 || !strcmp(next_name, "__init_end")))
 331                                 continue;
 332                         if (*mode != 'T' && *mode != 't' &&
 333                             *mode != 'W' && *mode != 'w')
 334                                 break;  /* only text is profiled */
 335                 }
 336
 337                 if (indx >= len / sizeof(*buf))
 338                         errx(EXIT_FAILURE,
 339                              _("profile address out of range. Wrong map file?"));
 340
 341                 while (step > 0 && indx < (next_add - add0) / step) {
 342                         if (optBins && (buf[indx] || optAll)) {
 343                                 if (!header_printed) {
 344                                         printf("%s:\n", fn_name);
 345                                         header_printed = 1;
 346                                 }
 347                                 printf("\t%llx\t%u\n", (indx - 1) * step + add0,
 348                                        buf[indx]);
 349                         }
 350                         this += buf[indx++];
 351                 }
 352                 total += this;
 353
 354                 if (optBins) {
 355                         if (optVerbose || this > 0)
 356                                 printf("  total\t\t\t\t%u\n", this);
 357                 } else if ((this || optAll) &&
 358                            (fn_len = next_add - fn_add) != 0) {
 359                         if (optVerbose)
 360                                 printf("%016llx %-40s %6u %8.4f\n", fn_add,
 361                                        fn_name, this, this / (double)fn_len);
 362                         else
 363                                 printf("%6u %-40s %8.4f\n",
 364                                        this, fn_name, this / (double)fn_len);
 365                         if (optSub && step > 0) {
 366                                 unsigned long long scan;
 367
 368                                 for (scan = (fn_add - add0) / step + 1;
 369                                      scan < (next_add - add0) / step;
 370                                      scan++) {
 371                                         unsigned long long addr;
 372                                         addr = (scan - 1) * step + add0;
 373                                         printf("\t%#llx\t%s+%#llx\t%u\n",
 374                                                addr, fn_name, addr - fn_add,
 375                                                buf[scan]);
 376                                 }
 377                         }
 378                 }
 379
 380                 fn_add = next_add;
 381                 strcpy(fn_name, next_name);
 382
 383                 maplineno++;
 384                 if (done)
 385                         break;
 386         }
 387
 388         /* clock ticks, out of kernel text - probably modules */
 389         printf("%6u %s\n", buf[len / sizeof(*buf) - 1], "*unknown*");
 390
 391         if (fn_add > add0)
 392                 rep = total / (double)(fn_add - add0);
 393
 394         /* trailer */
 395         if (optVerbose)
 396                 printf("%016x %-40s %6u %8.4f\n",
 397                        0, "total", total, rep);
 398         else
 399                 printf("%6u %-40s %8.4f\n",
 400                        total, _("total"), rep);
 401
 402         popenMap ? pclose(map) : fclose(map);
 403         exit(EXIT_SUCCESS);
 404 }