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:       "        -m mapfile      (Default: /boot/System.map)"
  39 //usage:     "\n        -p profile      (Default: /proc/profile)"
  40 //usage:     "\n        -M NUM          Set the profiling multiplier to NUM"
  41 //usage:     "\n        -i              Print only info about the sampling step"
  42 //usage:     "\n        -v              Verbose"
  43 //usage:     "\n        -a              Print all symbols, even if count is 0"
  44 //usage:     "\n        -b              Print individual histogram-bin counts"
  45 //usage:     "\n        -s              Print individual counters within functions"
  46 //usage:     "\n        -r              Reset all the counters (root only)"
  47 //usage:     "\n        -n              Disable byte order auto-detection"
  48
  49 #include "libbb.h"
  50 #include <sys/utsname.h>
  51
  52 #define S_LEN 128
  53
  54 /* These are the defaults */
  55 static const char defaultmap[] ALIGN1 = "/boot/System.map";
  56 static const char defaultpro[] ALIGN1 = "/proc/profile";
  57
  58 int readprofile_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  59 int readprofile_main(int argc UNUSED_PARAM, char **argv)
  60 {
  61         FILE *map;
  62         const char *mapFile, *proFile;
  63         unsigned long indx = 1;
  64         size_t len;
  65         uint64_t add0 = 0;
  66         unsigned int step;
  67         unsigned int *buf, total, fn_len;
  68         unsigned long long fn_add, next_add;     /* current and next address */
  69         char fn_name[S_LEN], next_name[S_LEN];   /* current and next name */
  70         char mapline[S_LEN];
  71         char mode[8];
  72         int maplineno = 1;
  73         int header_printed;
  74         int multiplier = 0;
  75         unsigned opt;
  76         enum {
  77                 OPT_M = (1 << 0),
  78                 OPT_m = (1 << 1),
  79                 OPT_p = (1 << 2),
  80                 OPT_n = (1 << 3),
  81                 OPT_a = (1 << 4),
  82                 OPT_b = (1 << 5),
  83                 OPT_s = (1 << 6),
  84                 OPT_i = (1 << 7),
  85                 OPT_r = (1 << 8),
  86                 OPT_v = (1 << 9),
  87         };
  88 #define optMult    (opt & OPT_M)
  89 #define optNative  (opt & OPT_n)
  90 #define optAll     (opt & OPT_a)
  91 #define optBins    (opt & OPT_b)
  92 #define optSub     (opt & OPT_s)
  93 #define optInfo    (opt & OPT_i)
  94 #define optReset   (opt & OPT_r)
  95 #define optVerbose (opt & OPT_v)
  96
  97 #define next (current^1)
  98
  99         proFile = defaultpro;
 100         mapFile = defaultmap;
 101
 102         opt = getopt32(argv, "M:+m:p:nabsirv", &multiplier, &mapFile, &proFile);
 103
 104         if (opt & (OPT_M|OPT_r)) { /* mult or reset, or both */
 105                 int fd, to_write;
 106
 107                 /*
 108                  * When writing the multiplier, if the length of the write is
 109                  * not sizeof(int), the multiplier is not changed
 110                  */
 111                 to_write = sizeof(int);
 112                 if (!optMult)
 113                         to_write = 1;  /* sth different from sizeof(int) */
 114
 115                 fd = xopen(defaultpro, O_WRONLY);
 116                 xwrite(fd, &multiplier, to_write);
 117                 close(fd);
 118                 return EXIT_SUCCESS;
 119         }
 120
 121         /*
 122          * Use an fd for the profiling buffer, to skip stdio overhead
 123          */
 124         len = MAXINT(ssize_t);
 125         buf = xmalloc_xopen_read_close(proFile, &len);
 126         if (!optNative) {
 127                 int entries = len / sizeof(*buf);
 128                 int big = 0, small = 0, i;
 129                 unsigned *p;
 130
 131                 for (p = buf+1; p < buf+entries; p++) {
 132                         if (*p & ~0U << (sizeof(*buf)*4))
 133                                 big++;
 134                         if (*p & ((1 << (sizeof(*buf)*4))-1))
 135                                 small++;
 136                 }
 137                 if (big > small) {
 138                         bb_error_msg("assuming reversed byte order, "
 139                                 "use -n to force native byte order");
 140                         for (p = buf; p < buf+entries; p++)
 141                                 for (i = 0; i < sizeof(*buf)/2; i++) {
 142                                         unsigned char *b = (unsigned char *) p;
 143                                         unsigned char tmp;
 144
 145                                         tmp = b[i];
 146                                         b[i] = b[sizeof(*buf)-i-1];
 147                                         b[sizeof(*buf)-i-1] = tmp;
 148                                 }
 149                 }
 150         }
 151
 152         step = buf[0];
 153         if (optInfo) {
 154                 printf("Sampling_step: %u\n", step);
 155                 return EXIT_SUCCESS;
 156         }
 157
 158         total = 0;
 159
 160         map = xfopen_for_read(mapFile);
 161
 162         while (fgets(mapline, S_LEN, map)) {
 163                 if (sscanf(mapline, "%llx %s %s", &fn_add, mode, fn_name) != 3)
 164                         bb_error_msg_and_die("%s(%i): wrong map line",
 165                                         mapFile, maplineno);
 166
 167                 if (!strcmp(fn_name, "_stext")) /* only elf works like this */ {
 168                         add0 = fn_add;
 169                         break;
 170                 }
 171                 maplineno++;
 172         }
 173
 174         if (!add0)
 175                 bb_error_msg_and_die("can't find \"_stext\" in %s", mapFile);
 176
 177         /*
 178          * Main loop.
 179          */
 180         while (fgets(mapline, S_LEN, map)) {
 181                 unsigned int this = 0;
 182
 183                 if (sscanf(mapline, "%llx %s %s", &next_add, mode, next_name) != 3)
 184                         bb_error_msg_and_die("%s(%i): wrong map line",
 185                                         mapFile, maplineno);
 186
 187                 header_printed = 0;
 188
 189                 /* ignore any LEADING (before a '[tT]' symbol is found)
 190                    Absolute symbols */
 191                 if ((*mode == 'A' || *mode == '?') && total == 0) continue;
 192                 if (*mode != 'T' && *mode != 't'
 193                  && *mode != 'W' && *mode != 'w'
 194                 ) {
 195                         break;  /* only text is profiled */
 196                 }
 197
 198                 if (indx >= len / sizeof(*buf))
 199                         bb_error_msg_and_die("profile address out of range. "
 200                                         "Wrong map file?");
 201
 202                 while (indx < (next_add-add0)/step) {
 203                         if (optBins && (buf[indx] || optAll)) {
 204                                 if (!header_printed) {
 205                                         printf("%s:\n", fn_name);
 206                                         header_printed = 1;
 207                                 }
 208                                 printf("\t%"PRIx64"\t%u\n", (indx - 1)*step + add0, buf[indx]);
 209                         }
 210                         this += buf[indx++];
 211                 }
 212                 total += this;
 213
 214                 if (optBins) {
 215                         if (optVerbose || this > 0)
 216                                 printf("  total\t\t\t\t%u\n", this);
 217                 } else if ((this || optAll)
 218                         && (fn_len = next_add-fn_add) != 0
 219                 ) {
 220                         if (optVerbose)
 221                                 printf("%016llx %-40s %6u %8.4f\n", fn_add,
 222                                         fn_name, this, this/(double)fn_len);
 223                         else
 224                                 printf("%6u %-40s %8.4f\n",
 225                                         this, fn_name, this/(double)fn_len);
 226                         if (optSub) {
 227                                 unsigned long long scan;
 228
 229                                 for (scan = (fn_add-add0)/step + 1;
 230                                      scan < (next_add-add0)/step; scan++) {
 231                                         unsigned long long addr;
 232
 233                                         addr = (scan - 1)*step + add0;
 234                                         printf("\t%#llx\t%s+%#llx\t%u\n",
 235                                                 addr, fn_name, addr - fn_add,
 236                                                 buf[scan]);
 237                                 }
 238                         }
 239                 }
 240
 241                 fn_add = next_add;
 242                 strcpy(fn_name, next_name);
 243
 244                 maplineno++;
 245         }
 246
 247         /* clock ticks, out of kernel text - probably modules */
 248         printf("%6u %s\n", buf[len/sizeof(*buf)-1], "*unknown*");
 249
 250         /* trailer */
 251         if (optVerbose)
 252                 printf("%016x %-40s %6u %8.4f\n",
 253                         0, "total", total, total/(double)(fn_add-add0));
 254         else
 255                 printf("%6u %-40s %8.4f\n",
 256                         total, "total", total/(double)(fn_add-add0));
 257
 258         fclose(map);
 259         free(buf);
 260
 261         return EXIT_SUCCESS;
 262 }