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_complementary = "M+"; /* -M N */
 103         opt = getopt32(argv, "M:m:p:nabsirv", &multiplier, &mapFile, &proFile);
 104
 105         if (opt & (OPT_M|OPT_r)) { /* mult or reset, or both */
 106                 int fd, to_write;
 107
 108                 /*
 109                  * When writing the multiplier, if the length of the write is
 110                  * not sizeof(int), the multiplier is not changed
 111                  */
 112                 to_write = sizeof(int);
 113                 if (!optMult)
 114                         to_write = 1;  /* sth different from sizeof(int) */
 115
 116                 fd = xopen(defaultpro, O_WRONLY);
 117                 xwrite(fd, &multiplier, to_write);
 118                 close(fd);
 119                 return EXIT_SUCCESS;
 120         }
 121
 122         /*
 123          * Use an fd for the profiling buffer, to skip stdio overhead
 124          */
 125         len = MAXINT(ssize_t);
 126         buf = xmalloc_xopen_read_close(proFile, &len);
 127         if (!optNative) {
 128                 int entries = len / sizeof(*buf);
 129                 int big = 0, small = 0, i;
 130                 unsigned *p;
 131
 132                 for (p = buf+1; p < buf+entries; p++) {
 133                         if (*p & ~0U << (sizeof(*buf)*4))
 134                                 big++;
 135                         if (*p & ((1 << (sizeof(*buf)*4))-1))
 136                                 small++;
 137                 }
 138                 if (big > small) {
 139                         bb_error_msg("assuming reversed byte order, "
 140                                 "use -n to force native byte order");
 141                         for (p = buf; p < buf+entries; p++)
 142                                 for (i = 0; i < sizeof(*buf)/2; i++) {
 143                                         unsigned char *b = (unsigned char *) p;
 144                                         unsigned char tmp;
 145
 146                                         tmp = b[i];
 147                                         b[i] = b[sizeof(*buf)-i-1];
 148                                         b[sizeof(*buf)-i-1] = tmp;
 149                                 }
 150                 }
 151         }
 152
 153         step = buf[0];
 154         if (optInfo) {
 155                 printf("Sampling_step: %u\n", step);
 156                 return EXIT_SUCCESS;
 157         }
 158
 159         total = 0;
 160
 161         map = xfopen_for_read(mapFile);
 162
 163         while (fgets(mapline, S_LEN, map)) {
 164                 if (sscanf(mapline, "%llx %s %s", &fn_add, mode, fn_name) != 3)
 165                         bb_error_msg_and_die("%s(%i): wrong map line",
 166                                         mapFile, maplineno);
 167
 168                 if (!strcmp(fn_name, "_stext")) /* only elf works like this */ {
 169                         add0 = fn_add;
 170                         break;
 171                 }
 172                 maplineno++;
 173         }
 174
 175         if (!add0)
 176                 bb_error_msg_and_die("can't find \"_stext\" in %s", mapFile);
 177
 178         /*
 179          * Main loop.
 180          */
 181         while (fgets(mapline, S_LEN, map)) {
 182                 unsigned int this = 0;
 183
 184                 if (sscanf(mapline, "%llx %s %s", &next_add, mode, next_name) != 3)
 185                         bb_error_msg_and_die("%s(%i): wrong map line",
 186                                         mapFile, maplineno);
 187
 188                 header_printed = 0;
 189
 190                 /* ignore any LEADING (before a '[tT]' symbol is found)
 191                    Absolute symbols */
 192                 if ((*mode == 'A' || *mode == '?') && total == 0) continue;
 193                 if (*mode != 'T' && *mode != 't'
 194                  && *mode != 'W' && *mode != 'w'
 195                 ) {
 196                         break;  /* only text is profiled */
 197                 }
 198
 199                 if (indx >= len / sizeof(*buf))
 200                         bb_error_msg_and_die("profile address out of range. "
 201                                         "Wrong map file?");
 202
 203                 while (indx < (next_add-add0)/step) {
 204                         if (optBins && (buf[indx] || optAll)) {
 205                                 if (!header_printed) {
 206                                         printf("%s:\n", fn_name);
 207                                         header_printed = 1;
 208                                 }
 209                                 printf("\t%"PRIx64"\t%u\n", (indx - 1)*step + add0, buf[indx]);
 210                         }
 211                         this += buf[indx++];
 212                 }
 213                 total += this;
 214
 215                 if (optBins) {
 216                         if (optVerbose || this > 0)
 217                                 printf("  total\t\t\t\t%u\n", this);
 218                 } else if ((this || optAll)
 219                         && (fn_len = next_add-fn_add) != 0
 220                 ) {
 221                         if (optVerbose)
 222                                 printf("%016llx %-40s %6u %8.4f\n", fn_add,
 223                                         fn_name, this, this/(double)fn_len);
 224                         else
 225                                 printf("%6u %-40s %8.4f\n",
 226                                         this, fn_name, this/(double)fn_len);
 227                         if (optSub) {
 228                                 unsigned long long scan;
 229
 230                                 for (scan = (fn_add-add0)/step + 1;
 231                                      scan < (next_add-add0)/step; scan++) {
 232                                         unsigned long long addr;
 233
 234                                         addr = (scan - 1)*step + add0;
 235                                         printf("\t%#llx\t%s+%#llx\t%u\n",
 236                                                 addr, fn_name, addr - fn_add,
 237                                                 buf[scan]);
 238                                 }
 239                         }
 240                 }
 241
 242                 fn_add = next_add;
 243                 strcpy(fn_name, next_name);
 244
 245                 maplineno++;
 246         }
 247
 248         /* clock ticks, out of kernel text - probably modules */
 249         printf("%6u %s\n", buf[len/sizeof(*buf)-1], "*unknown*");
 250
 251         /* trailer */
 252         if (optVerbose)
 253                 printf("%016x %-40s %6u %8.4f\n",
 254                         0, "total", total, total/(double)(fn_add-add0));
 255         else
 256                 printf("%6u %-40s %8.4f\n",
 257                         total, "total", total/(double)(fn_add-add0));
 258
 259         fclose(map);
 260         free(buf);
 261
 262         return EXIT_SUCCESS;
 263 }