LXR busybox/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#include "libbb.h"
  36#include <sys/utsname.h>
  37
  38#define S_LEN 128
  39
  40/* These are the defaults */
  41static const char defaultmap[] ALIGN1 = "/boot/System.map";
  42static const char defaultpro[] ALIGN1 = "/proc/profile";
  43
  44int readprofile_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  45int readprofile_main(int argc UNUSED_PARAM, char **argv)
  46{
  47        FILE *map;
  48        const char *mapFile, *proFile;
  49        unsigned long indx = 1;
  50        size_t len;
  51        uint64_t add0 = 0;
  52        unsigned int step;
  53        unsigned int *buf, total, fn_len;
  54        unsigned long long fn_add, next_add;     /* current and next address */
  55        char fn_name[S_LEN], next_name[S_LEN];   /* current and next name */
  56        char mapline[S_LEN];
  57        char mode[8];
  58        int maplineno = 1;
  59        int header_printed;
  60        int multiplier = 0;
  61        unsigned opt;
  62        enum {
  63                OPT_M = (1 << 0),
  64                OPT_m = (1 << 1),
  65                OPT_p = (1 << 2),
  66                OPT_n = (1 << 3),
  67                OPT_a = (1 << 4),
  68                OPT_b = (1 << 5),
  69                OPT_s = (1 << 6),
  70                OPT_i = (1 << 7),
  71                OPT_r = (1 << 8),
  72                OPT_v = (1 << 9),
  73        };
  74#define optMult    (opt & OPT_M)
  75#define optNative  (opt & OPT_n)
  76#define optAll     (opt & OPT_a)
  77#define optBins    (opt & OPT_b)
  78#define optSub     (opt & OPT_s)
  79#define optInfo    (opt & OPT_i)
  80#define optReset   (opt & OPT_r)
  81#define optVerbose (opt & OPT_v)
  82
  83#define next (current^1)
  84
  85        proFile = defaultpro;
  86        mapFile = defaultmap;
  87
  88        opt_complementary = "M+"; /* -M N */
  89        opt = getopt32(argv, "M:m:p:nabsirv", &multiplier, &mapFile, &proFile);
  90
  91        if (opt & (OPT_M|OPT_r)) { /* mult or reset, or both */
  92                int fd, to_write;
  93
  94                /*
  95                 * When writing the multiplier, if the length of the write is
  96                 * not sizeof(int), the multiplier is not changed
  97                 */
  98                to_write = sizeof(int);
  99                if (!optMult)
 100                        to_write = 1;  /* sth different from sizeof(int) */
 101
 102                fd = xopen(defaultpro, O_WRONLY);
 103                xwrite(fd, &multiplier, to_write);
 104                close(fd);
 105                return EXIT_SUCCESS;
 106        }
 107
 108        /*
 109         * Use an fd for the profiling buffer, to skip stdio overhead
 110         */
 111        len = MAXINT(ssize_t);
 112        buf = xmalloc_xopen_read_close(proFile, &len);
 113        if (!optNative) {
 114                int entries = len / sizeof(*buf);
 115                int big = 0, small = 0, i;
 116                unsigned *p;
 117
 118                for (p = buf+1; p < buf+entries; p++) {
 119                        if (*p & ~0U << (sizeof(*buf)*4))
 120                                big++;
 121                        if (*p & ((1 << (sizeof(*buf)*4))-1))
 122                                small++;
 123                }
 124                if (big > small) {
 125                        bb_error_msg("assuming reversed byte order, "
 126                                "use -n to force native byte order");
 127                        for (p = buf; p < buf+entries; p++)
 128                                for (i = 0; i < sizeof(*buf)/2; i++) {
 129                                        unsigned char *b = (unsigned char *) p;
 130                                        unsigned char tmp;
 131
 132                                        tmp = b[i];
 133                                        b[i] = b[sizeof(*buf)-i-1];
 134                                        b[sizeof(*buf)-i-1] = tmp;
 135                                }
 136                }
 137        }
 138
 139        step = buf[0];
 140        if (optInfo) {
 141                printf("Sampling_step: %i\n", step);
 142                return EXIT_SUCCESS;
 143        }
 144
 145        total = 0;
 146
 147        map = xfopen_for_read(mapFile);
 148
 149        while (fgets(mapline, S_LEN, map)) {
 150                if (sscanf(mapline, "%llx %s %s", &fn_add, mode, fn_name) != 3)
 151                        bb_error_msg_and_die("%s(%i): wrong map line",
 152                                             mapFile, maplineno);
 153
 154                if (!strcmp(fn_name, "_stext")) /* only elf works like this */ {
 155                        add0 = fn_add;
 156                        break;
 157                }
 158                maplineno++;
 159        }
 160
 161        if (!add0)
 162                bb_error_msg_and_die("can't find \"_stext\" in %s", mapFile);
 163
 164        /*
 165         * Main loop.
 166         */
 167        while (fgets(mapline, S_LEN, map)) {
 168                unsigned int this = 0;
 169
 170                if (sscanf(mapline, "%llx %s %s", &next_add, mode, next_name) != 3)
 171                        bb_error_msg_and_die("%s(%i): wrong map line",
 172                                        mapFile, maplineno);
 173
 174                header_printed = 0;
 175
 176                /* ignore any LEADING (before a '[tT]' symbol is found)
 177                   Absolute symbols */
 178                if ((*mode == 'A' || *mode == '?') && total == 0) continue;
 179                if (*mode != 'T' && *mode != 't'
 180                 && *mode != 'W' && *mode != 'w'
 181                ) {
 182                        break;  /* only text is profiled */
 183                }
 184
 185                if (indx >= len / sizeof(*buf))
 186                        bb_error_msg_and_die("profile address out of range. "
 187                                             "Wrong map file?");
 188
 189                while (indx < (next_add-add0)/step) {
 190                        if (optBins && (buf[indx] || optAll)) {
 191                                if (!header_printed) {
 192                                        printf("%s:\n", fn_name);
 193                                        header_printed = 1;
 194                                }
 195                                printf("\t%"PRIx64"\t%u\n", (indx - 1)*step + add0, buf[indx]);
 196                        }
 197                        this += buf[indx++];
 198                }
 199                total += this;
 200
 201                if (optBins) {
 202                        if (optVerbose || this > 0)
 203                                printf("  total\t\t\t\t%u\n", this);
 204                } else if ((this || optAll)
 205                        && (fn_len = next_add-fn_add) != 0
 206                ) {
 207                        if (optVerbose)
 208                                printf("%016llx %-40s %6i %8.4f\n", fn_add,
 209                                       fn_name, this, this/(double)fn_len);
 210                        else
 211                                printf("%6i %-40s %8.4f\n",
 212                                       this, fn_name, this/(double)fn_len);
 213                        if (optSub) {
 214                                unsigned long long scan;
 215
 216                                for (scan = (fn_add-add0)/step + 1;
 217                                     scan < (next_add-add0)/step; scan++) {
 218                                        unsigned long long addr;
 219
 220                                        addr = (scan - 1)*step + add0;
 221                                        printf("\t%#llx\t%s+%#llx\t%u\n",
 222                                               addr, fn_name, addr - fn_add,
 223                                               buf[scan]);
 224                                }
 225                        }
 226                }
 227
 228                fn_add = next_add;
 229                strcpy(fn_name, next_name);
 230
 231                maplineno++;
 232        }
 233
 234        /* clock ticks, out of kernel text - probably modules */
 235        printf("%6i %s\n", buf[len/sizeof(*buf)-1], "*unknown*");
 236
 237        /* trailer */
 238        if (optVerbose)
 239                printf("%016x %-40s %6i %8.4f\n",
 240                       0, "total", total, total/(double)(fn_add-add0));
 241        else
 242                printf("%6i %-40s %8.4f\n",
 243                       total, "total", total/(double)(fn_add-add0));
 244
 245        fclose(map);
 246        free(buf);
 247
 248        return EXIT_SUCCESS;
 249}
 250