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         size_t len;
  85
  86         if (uname(&uname_info))
  87                 return "";
  88         len = strlen(BOOT_SYSTEM_MAP) + strlen(uname_info.release) + 1;
  89         s = xmalloc(len);
  90         strcpy(s, BOOT_SYSTEM_MAP);
  91         strcat(s, uname_info.release);
  92         return s;
  93 }
  94
  95 static void __attribute__((__noreturn__)) usage(void)
  96 {
  97         FILE *out = stdout;
  98         fputs(USAGE_HEADER, out);
  99         fprintf(out, _(" %s [options]\n"), program_invocation_short_name);
 100
 101         fputs(USAGE_SEPARATOR, out);
 102         fputs(_("Display kernel profiling information.\n"), out);
 103
 104         fputs(USAGE_OPTIONS, out);
 105         fprintf(out,
 106               _(" -m, --mapfile <mapfile>   (defaults: \"%s\" and\n"), defaultmap);
 107         fprintf(out,
 108               _("                                      \"%s\")\n"), boot_uname_r_str());
 109         fprintf(out,
 110               _(" -p, --profile <pro-file>  (default:  \"%s\")\n"), defaultpro);
 111         fputs(_(" -M, --multiplier <mult>   set the profiling multiplier to <mult>\n"), out);
 112         fputs(_(" -i, --info                print only info about the sampling step\n"), out);
 113         fputs(_(" -v, --verbose             print verbose data\n"), out);
 114         fputs(_(" -a, --all                 print all symbols, even if count is 0\n"), out);
 115         fputs(_(" -b, --histbin             print individual histogram-bin counts\n"), out);
 116         fputs(_(" -s, --counters            print individual counters within functions\n"), out);
 117         fputs(_(" -r, --reset               reset all the counters (root only)\n"), out);
 118         fputs(_(" -n, --no-auto             disable byte order auto-detection\n"), out);
 119         fputs(USAGE_SEPARATOR, out);
 120         fprintf(out, USAGE_HELP_OPTIONS(27));
 121         fprintf(out, USAGE_MAN_TAIL("readprofile(8)"));
 122         exit(EXIT_SUCCESS);
 123 }
 124
 125 int main(int argc, char **argv)
 126 {
 127         FILE *map;
 128         int proFd, has_mult = 0, multiplier = 0;
 129         char *mapFile, *proFile;
 130         size_t len = 0, indx = 1;
 131         unsigned long long add0 = 0;
 132         unsigned int step;
 133         unsigned int *buf, total, fn_len;
 134         unsigned long long fn_add = 0, next_add; /* current and next address */
 135         char fn_name[S_LEN], next_name[S_LEN];  /* current and next name */
 136         char mode[8];
 137         int c;
 138         ssize_t rc;
 139         int optAll = 0, optInfo = 0, optReset = 0, optVerbose = 0, optNative = 0;
 140         int optBins = 0, optSub = 0;
 141         char mapline[S_LEN];
 142         int maplineno = 1;
 143         int popenMap;           /* flag to tell if popen() has been used */
 144         int header_printed;
 145         double rep = 0;
 146
 147         static const struct option longopts[] = {
 148                 {"mapfile", required_argument, NULL, 'm'},
 149                 {"profile", required_argument, NULL, 'p'},
 150                 {"multiplier", required_argument, NULL, 'M'},
 151                 {"info", no_argument, NULL, 'i'},
 152                 {"verbose", no_argument, NULL, 'v'},
 153                 {"all", no_argument, NULL, 'a'},
 154                 {"histbin", no_argument, NULL, 'b'},
 155                 {"counters", no_argument, NULL, 's'},
 156                 {"reset", no_argument, NULL, 'r'},
 157                 {"no-auto", no_argument, NULL, 'n'},
 158                 {"version", no_argument, NULL, 'V'},
 159                 {"help", no_argument, NULL, 'h'},
 160                 {NULL, 0, NULL, 0}
 161         };
 162
 163 #define next (current^1)
 164
 165         setlocale(LC_ALL, "");
 166         bindtextdomain(PACKAGE, LOCALEDIR);
 167         textdomain(PACKAGE);
 168         close_stdout_atexit();
 169
 170         proFile = defaultpro;
 171         mapFile = defaultmap;
 172
 173         while ((c = getopt_long(argc, argv, "m:p:M:ivabsrnVh", longopts, NULL)) != -1) {
 174                 switch (c) {
 175                 case 'm':
 176                         mapFile = optarg;
 177                         break;
 178                 case 'n':
 179                         optNative++;
 180                         break;
 181                 case 'p':
 182                         proFile = optarg;
 183                         break;
 184                 case 'a':
 185                         optAll++;
 186                         break;
 187                 case 'b':
 188                         optBins++;
 189                         break;
 190                 case 's':
 191                         optSub++;
 192                         break;
 193                 case 'i':
 194                         optInfo++;
 195                         break;
 196                 case 'M':
 197                         multiplier = strtol_or_err(optarg, _("failed to parse multiplier"));
 198                         has_mult = 1;
 199                         break;
 200                 case 'r':
 201                         optReset++;
 202                         break;
 203                 case 'v':
 204                         optVerbose++;
 205                         break;
 206
 207                 case 'V':
 208                         print_version(EXIT_SUCCESS);
 209                 case 'h':
 210                         usage();
 211                 default:
 212                         errtryhelp(EXIT_FAILURE);
 213                 }
 214         }
 215
 216         if (optReset || has_mult) {
 217                 int fd, to_write;
 218
 219                 /* When writing the multiplier, if the length of the
 220                  * write is not sizeof(int), the multiplier is not
 221                  * changed. */
 222                 if (has_mult) {
 223                         to_write = sizeof(int);
 224                 } else {
 225                         multiplier = 0;
 226                         /* sth different from sizeof(int) */
 227                         to_write = 1;
 228                 }
 229                 /* try to become root, just in case */
 230                 ignore_result( setuid(0) );
 231                 fd = open(defaultpro, O_WRONLY);
 232                 if (fd < 0)
 233                         err(EXIT_FAILURE, "%s", defaultpro);
 234                 if (write(fd, &multiplier, to_write) != to_write)
 235                         err(EXIT_FAILURE, _("error writing %s"), defaultpro);
 236                 close(fd);
 237                 exit(EXIT_SUCCESS);
 238         }
 239
 240         /* Use an fd for the profiling buffer, to skip stdio overhead */
 241         if (((proFd = open(proFile, O_RDONLY)) < 0)
 242             || ((int)(len = lseek(proFd, 0, SEEK_END)) < 0)
 243             || (lseek(proFd, 0, SEEK_SET) < 0))
 244                 err(EXIT_FAILURE, "%s", proFile);
 245         if (!len)
 246                 errx(EXIT_FAILURE, "%s: %s", proFile, _("input file is empty"));
 247
 248         buf = xmalloc(len);
 249
 250         rc = read(proFd, buf, len);
 251         if (rc < 0 || (size_t) rc != len)
 252                 err(EXIT_FAILURE, "%s", proFile);
 253         close(proFd);
 254
 255         if (!optNative) {
 256                 int entries = len / sizeof(*buf);
 257                 int big = 0, small = 0;
 258                 unsigned *p;
 259                 size_t i;
 260
 261                 for (p = buf + 1; p < buf + entries; p++) {
 262                         if (*p & ~0U << ((unsigned) sizeof(*buf) * 4U))
 263                                 big++;
 264                         if (*p & ((1U << ((unsigned) sizeof(*buf) * 4U)) - 1U))
 265                                 small++;
 266                 }
 267                 if (big > small) {
 268                         warnx(_("Assuming reversed byte order. "
 269                                 "Use -n to force native byte order."));
 270                         for (p = buf; p < buf + entries; p++)
 271                                 for (i = 0; i < sizeof(*buf) / 2; i++) {
 272                                         unsigned char *b = (unsigned char *)p;
 273                                         unsigned char tmp;
 274                                         tmp = b[i];
 275                                         b[i] = b[sizeof(*buf) - i - 1];
 276                                         b[sizeof(*buf) - i - 1] = tmp;
 277                                 }
 278                 }
 279         }
 280
 281         step = buf[0];
 282         if (optInfo) {
 283                 printf(_("Sampling_step: %u\n"), step);
 284                 exit(EXIT_SUCCESS);
 285         }
 286
 287         total = 0;
 288
 289         map = myopen(mapFile, "r", &popenMap);
 290         if (map == NULL && mapFile == defaultmap) {
 291                 mapFile = boot_uname_r_str();
 292                 map = myopen(mapFile, "r", &popenMap);
 293         }
 294         if (map == NULL)
 295                 err(EXIT_FAILURE, "%s", mapFile);
 296
 297         while (fgets(mapline, S_LEN, map)) {
 298                 if (sscanf(mapline, "%llx %7[^\n ] %127[^\n ]", &fn_add, mode, fn_name) != 3)
 299                         errx(EXIT_FAILURE, _("%s(%i): wrong map line"), mapFile,
 300                              maplineno);
 301                 /* only elf works like this */
 302                 if (!strcmp(fn_name, "_stext") || !strcmp(fn_name, "__stext")) {
 303                         add0 = fn_add;
 304                         break;
 305                 }
 306                 maplineno++;
 307         }
 308
 309         if (!add0)
 310                 errx(EXIT_FAILURE, _("can't find \"_stext\" in %s"), mapFile);
 311
 312         /*
 313          * Main loop.
 314          */
 315         while (fgets(mapline, S_LEN, map)) {
 316                 unsigned int this = 0;
 317                 int done = 0;
 318
 319                 if (sscanf(mapline, "%llx %7[^\n ] %127[^\n ]", &next_add, mode, next_name) != 3)
 320                         errx(EXIT_FAILURE, _("%s(%i): wrong map line"), mapFile,
 321                              maplineno);
 322                 header_printed = 0;
 323
 324                 /* the kernel only profiles up to _etext */
 325                 if (!strcmp(next_name, "_etext") ||
 326                     !strcmp(next_name, "__etext"))
 327                         done = 1;
 328                 else {
 329                         /* ignore any LEADING (before a '[tT]' symbol
 330                          * is found) Absolute symbols and __init_end
 331                          * because some architectures place it before
 332                          * .text section */
 333                         if ((*mode == 'A' || *mode == '?')
 334                             && (total == 0 || !strcmp(next_name, "__init_end")))
 335                                 continue;
 336                         if (*mode != 'T' && *mode != 't' &&
 337                             *mode != 'W' && *mode != 'w')
 338                                 break;  /* only text is profiled */
 339                 }
 340
 341                 if (indx >= len / sizeof(*buf))
 342                         errx(EXIT_FAILURE,
 343                              _("profile address out of range. Wrong map file?"));
 344
 345                 while (step > 0 && indx < (next_add - add0) / step) {
 346                         if (optBins && (buf[indx] || optAll)) {
 347                                 if (!header_printed) {
 348                                         printf("%s:\n", fn_name);
 349                                         header_printed = 1;
 350                                 }
 351                                 printf("\t%llx\t%u\n", (indx - 1) * step + add0,
 352                                        buf[indx]);
 353                         }
 354                         this += buf[indx++];
 355                 }
 356                 total += this;
 357
 358                 if (optBins) {
 359                         if (optVerbose || this > 0)
 360                                 printf("  total\t\t\t\t%u\n", this);
 361                 } else if ((this || optAll) &&
 362                            (fn_len = next_add - fn_add) != 0) {
 363                         if (optVerbose)
 364                                 printf("%016llx %-40s %6u %8.4f\n", fn_add,
 365                                        fn_name, this, this / (double)fn_len);
 366                         else
 367                                 printf("%6u %-40s %8.4f\n",
 368                                        this, fn_name, this / (double)fn_len);
 369                         if (optSub && step > 0) {
 370                                 unsigned long long scan;
 371
 372                                 for (scan = (fn_add - add0) / step + 1;
 373                                      scan < (next_add - add0) / step;
 374                                      scan++) {
 375                                         unsigned long long addr;
 376                                         addr = (scan - 1) * step + add0;
 377                                         printf("\t%#llx\t%s+%#llx\t%u\n",
 378                                                addr, fn_name, addr - fn_add,
 379                                                buf[scan]);
 380                                 }
 381                         }
 382                 }
 383
 384                 fn_add = next_add;
 385                 strcpy(fn_name, next_name);
 386
 387                 maplineno++;
 388                 if (done)
 389                         break;
 390         }
 391
 392         /* clock ticks, out of kernel text - probably modules */
 393         printf("%6u %s\n", buf[len / sizeof(*buf) - 1], "*unknown*");
 394
 395         if (fn_add > add0)
 396                 rep = total / (double)(fn_add - add0);
 397
 398         /* trailer */
 399         if (optVerbose)
 400                 printf("%016x %-40s %6u %8.4f\n",
 401                        0, "total", total, rep);
 402         else
 403                 printf("%6u %-40s %8.4f\n",
 404                        total, _("total"), rep);
 405
 406         popenMap ? pclose(map) : fclose(map);
 407         exit(EXIT_SUCCESS);
 408 }