util-linux/readprofile.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  *  readprofile.c - used to read /proc/profile
   4  *
   5  *  Copyright (C) 1994,1996 Alessandro Rubini (rubini@ipvvis.unipv.it)
   6  *
   7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8  */
   9
  10 /*
  11  * 1999-02-22 Arkadiusz Mickiewicz <misiek@pld.ORG.PL>
  12  * - added Native Language Support
  13  * 1999-09-01 Stephane Eranian <eranian@cello.hpl.hp.com>
  14  * - 64bit clean patch
  15  * 3Feb2001 Andrew Morton <andrewm@uow.edu.au>
  16  * - -M option to write profile multiplier.
  17  * 2001-11-07 Werner Almesberger <wa@almesberger.net>
  18  * - byte order auto-detection and -n option
  19  * 2001-11-09 Werner Almesberger <wa@almesberger.net>
  20  * - skip step size (index 0)
  21  * 2002-03-09 John Levon <moz@compsoc.man.ac.uk>
  22  * - make maplineno do something
  23  * 2002-11-28 Mads Martin Joergensen +
  24  * - also try /boot/System.map-`uname -r`
  25  * 2003-04-09 Werner Almesberger <wa@almesberger.net>
  26  * - fixed off-by eight error and improved heuristics in byte order detection
  27  * 2003-08-12 Nikita Danilov <Nikita@Namesys.COM>
  28  * - added -s option; example of use:
  29  * "readprofile -s -m /boot/System.map-test | grep __d_lookup | sort -n -k3"
  30  *
  31  * Taken from util-linux and adapted for busybox by
  32  * Paul Mundt <lethal@linux-sh.org>.
  33  */
  34
  35 //usage:#define readprofile_trivial_usage
  36 //usage:       "[OPTIONS]"
  37 //usage:#define readprofile_full_usage "\n\n"
  38 //usage:       "Options:"
  39 //usage:     "\n        -m mapfile      (Default: /boot/System.map)"
  40 //usage:     "\n        -p profile      (Default: /proc/profile)"
  41 //usage:     "\n        -M NUM          Set the profiling multiplier to NUM"
  42 //usage:     "\n        -i              Print only info about the sampling step"
  43 //usage:     "\n        -v              Verbose"
  44 //usage:     "\n        -a              Print all symbols, even if count is 0"
  45 //usage:     "\n        -b              Print individual histogram-bin counts"
  46 //usage:     "\n        -s              Print individual counters within functions"
  47 //usage:     "\n        -r              Reset all the counters (root only)"
  48 //usage:     "\n        -n              Disable byte order auto-detection"
  49
  50 #include "libbb.h"
  51 #include <sys/utsname.h>
  52
  53 #define S_LEN 128
  54
  55 /* These are the defaults */
  56 static const char defaultmap[] ALIGN1 = "/boot/System.map";
  57 static const char defaultpro[] ALIGN1 = "/proc/profile";
  58
  59 int readprofile_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  60 int readprofile_main(int argc UNUSED_PARAM, char **argv)
  61 {
  62         FILE *map;
  63         const char *mapFile, *proFile;
  64         unsigned long indx = 1;
  65         size_t len;
  66         uint64_t add0 = 0;
  67         unsigned int step;
  68         unsigned int *buf, total, fn_len;
  69         unsigned long long fn_add, next_add;     /* current and next address */
  70         char fn_name[S_LEN], next_name[S_LEN];   /* current and next name */
  71         char mapline[S_LEN];
  72         char mode[8];
  73         int maplineno = 1;
  74         int header_printed;
  75         int multiplier = 0;
  76         unsigned opt;
  77         enum {
  78                 OPT_M = (1 << 0),
  79                 OPT_m = (1 << 1),
  80                 OPT_p = (1 << 2),
  81                 OPT_n = (1 << 3),
  82                 OPT_a = (1 << 4),
  83                 OPT_b = (1 << 5),
  84                 OPT_s = (1 << 6),
  85                 OPT_i = (1 << 7),
  86                 OPT_r = (1 << 8),
  87                 OPT_v = (1 << 9),
  88         };
  89 #define optMult    (opt & OPT_M)
  90 #define optNative  (opt & OPT_n)
  91 #define optAll     (opt & OPT_a)
  92 #define optBins    (opt & OPT_b)
  93 #define optSub     (opt & OPT_s)
  94 #define optInfo    (opt & OPT_i)
  95 #define optReset   (opt & OPT_r)
  96 #define optVerbose (opt & OPT_v)
  97
  98 #define next (current^1)
  99
 100         proFile = defaultpro;
 101         mapFile = defaultmap;
 102
 103         opt_complementary = "M+"; /* -M N */
 104         opt = getopt32(argv, "M:m:p:nabsirv", &multiplier, &mapFile, &proFile);
 105
 106         if (opt & (OPT_M|OPT_r)) { /* mult or reset, or both */
 107                 int fd, to_write;
 108
 109                 /*
 110                  * When writing the multiplier, if the length of the write is
 111                  * not sizeof(int), the multiplier is not changed
 112                  */
 113                 to_write = sizeof(int);
 114                 if (!optMult)
 115                         to_write = 1;  /* sth different from sizeof(int) */
 116
 117                 fd = xopen(defaultpro, O_WRONLY);
 118                 xwrite(fd, &multiplier, to_write);
 119                 close(fd);
 120                 return EXIT_SUCCESS;
 121         }
 122
 123         /*
 124          * Use an fd for the profiling buffer, to skip stdio overhead
 125          */
 126         len = MAXINT(ssize_t);
 127         buf = xmalloc_xopen_read_close(proFile, &len);
 128         if (!optNative) {
 129                 int entries = len / sizeof(*buf);
 130                 int big = 0, small = 0, i;
 131                 unsigned *p;
 132
 133                 for (p = buf+1; p < buf+entries; p++) {
 134                         if (*p & ~0U << (sizeof(*buf)*4))
 135                                 big++;
 136                         if (*p & ((1 << (sizeof(*buf)*4))-1))
 137                                 small++;
 138                 }
 139                 if (big > small) {
 140                         bb_error_msg("assuming reversed byte order, "
 141                                 "use -n to force native byte order");
 142                         for (p = buf; p < buf+entries; p++)
 143                                 for (i = 0; i < sizeof(*buf)/2; i++) {
 144                                         unsigned char *b = (unsigned char *) p;
 145                                         unsigned char tmp;
 146
 147                                         tmp = b[i];
 148                                         b[i] = b[sizeof(*buf)-i-1];
 149                                         b[sizeof(*buf)-i-1] = tmp;
 150                                 }
 151                 }
 152         }
 153
 154         step = buf[0];
 155         if (optInfo) {
 156                 printf("Sampling_step: %i\n", step);
 157                 return EXIT_SUCCESS;
 158         }
 159
 160         total = 0;
 161
 162         map = xfopen_for_read(mapFile);
 163
 164         while (fgets(mapline, S_LEN, map)) {
 165                 if (sscanf(mapline, "%llx %s %s", &fn_add, mode, fn_name) != 3)
 166                         bb_error_msg_and_die("%s(%i): wrong map line",
 167                                              mapFile, maplineno);
 168
 169                 if (!strcmp(fn_name, "_stext")) /* only elf works like this */ {
 170                         add0 = fn_add;
 171                         break;
 172                 }
 173                 maplineno++;
 174         }
 175
 176         if (!add0)
 177                 bb_error_msg_and_die("can't find \"_stext\" in %s", mapFile);
 178
 179         /*
 180          * Main loop.
 181          */
 182         while (fgets(mapline, S_LEN, map)) {
 183                 unsigned int this = 0;
 184
 185                 if (sscanf(mapline, "%llx %s %s", &next_add, mode, next_name) != 3)
 186                         bb_error_msg_and_die("%s(%i): wrong map line",
 187                                         mapFile, maplineno);
 188
 189                 header_printed = 0;
 190
 191                 /* ignore any LEADING (before a '[tT]' symbol is found)
 192                    Absolute symbols */
 193                 if ((*mode == 'A' || *mode == '?') && total == 0) continue;
 194                 if (*mode != 'T' && *mode != 't'
 195                  && *mode != 'W' && *mode != 'w'
 196                 ) {
 197                         break;  /* only text is profiled */
 198                 }
 199
 200                 if (indx >= len / sizeof(*buf))
 201                         bb_error_msg_and_die("profile address out of range. "
 202                                              "Wrong map file?");
 203
 204                 while (indx < (next_add-add0)/step) {
 205                         if (optBins && (buf[indx] || optAll)) {
 206                                 if (!header_printed) {
 207                                         printf("%s:\n", fn_name);
 208                                         header_printed = 1;
 209                                 }
 210                                 printf("\t%"PRIx64"\t%u\n", (indx - 1)*step + add0, buf[indx]);
 211                         }
 212                         this += buf[indx++];
 213                 }
 214                 total += this;
 215
 216                 if (optBins) {
 217                         if (optVerbose || this > 0)
 218                                 printf("  total\t\t\t\t%u\n", this);
 219                 } else if ((this || optAll)
 220                         && (fn_len = next_add-fn_add) != 0
 221                 ) {
 222                         if (optVerbose)
 223                                 printf("%016llx %-40s %6i %8.4f\n", fn_add,
 224                                        fn_name, this, this/(double)fn_len);
 225                         else
 226                                 printf("%6i %-40s %8.4f\n",
 227                                        this, fn_name, this/(double)fn_len);
 228                         if (optSub) {
 229                                 unsigned long long scan;
 230
 231                                 for (scan = (fn_add-add0)/step + 1;
 232                                      scan < (next_add-add0)/step; scan++) {
 233                                         unsigned long long addr;
 234
 235                                         addr = (scan - 1)*step + add0;
 236                                         printf("\t%#llx\t%s+%#llx\t%u\n",
 237                                                addr, fn_name, addr - fn_add,
 238                                                buf[scan]);
 239                                 }
 240                         }
 241                 }
 242
 243                 fn_add = next_add;
 244                 strcpy(fn_name, next_name);
 245
 246                 maplineno++;
 247         }
 248
 249         /* clock ticks, out of kernel text - probably modules */
 250         printf("%6i %s\n", buf[len/sizeof(*buf)-1], "*unknown*");
 251
 252         /* trailer */
 253         if (optVerbose)
 254                 printf("%016x %-40s %6i %8.4f\n",
 255                        0, "total", total, total/(double)(fn_add-add0));
 256         else
 257                 printf("%6i %-40s %8.4f\n",
 258                        total, "total", total/(double)(fn_add-add0));
 259
 260         fclose(map);
 261         free(buf);
 262
 263         return EXIT_SUCCESS;
 264 }