usr.bin/pctrack/pctrack.c

   1 /*-
   2  * Copyright (c) 2002 Jake Burkholder
   3  * Copyright (c) 2004 Robert Watson
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  25  * SUCH DAMAGE.
  26  *
  27  * $DragonFly: src/usr.bin/pctrack/pctrack.c,v 1.2 2008/09/02 11:50:46 matthias Exp $
  28  */
  29
  30 #include <sys/kinfo.h>
  31 #include <sys/types.h>
  32 #include <sys/ktr.h>
  33 #include <sys/mman.h>
  34 #include <sys/stat.h>
  35 #include <sys/queue.h>
  36
  37 #include <err.h>
  38 #include <fcntl.h>
  39 #include <kvm.h>
  40 #include <limits.h>
  41 #include <nlist.h>
  42 #include <stdint.h>
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45 #include <string.h>
  46 #include <stddef.h>
  47 #include <unistd.h>
  48
  49 #define SBUFLEN 128
  50
  51 static void usage(void);
  52 static void do_output(int, int, struct kinfo_pcheader *, struct kinfo_pctrack *, int);
  53 static void read_symbols(const char *);
  54 static const char *address_to_symbol(void *);
  55
  56 static struct nlist nl[] = {
  57         { .n_name = "_ncpus" },
  58         { .n_name = "_cputime_pcheader" },
  59         { .n_name = "_cputime_pctrack" },
  60         { .n_name = NULL }
  61 };
  62
  63 static char corefile[PATH_MAX];
  64 static char execfile[PATH_MAX];
  65 static char errbuf[_POSIX2_LINE_MAX];
  66
  67 static int sflag;
  68 static int iflag;
  69 static int nflag;
  70 static int fflag;
  71 static int cflag = -1;
  72 static int Nflag;
  73 static int Mflag;
  74
  75 /*
  76  * Reads the cputime_pctrack[] structure from the kernel and displays
  77  * the results in a human readable format.
  78  */
  79 int
  80 main(int ac, char **av)
  81 {
  82         struct kinfo_pcheader pchead;
  83         struct kinfo_pctrack pctrack;
  84         kvm_t *kd;
  85         int ntrack;
  86         int ncpus;
  87         int cpu;
  88         int repeat;
  89         int c;
  90
  91         /*
  92          * Parse commandline arguments.
  93          */
  94         while ((c = getopt(ac, av, "nsifc:N:M:")) != -1) {
  95                 switch (c) {
  96                 case 'N':
  97                         if (strlcpy(execfile, optarg, sizeof(execfile))
  98                             >= sizeof(execfile))
  99                                 errx(1, "%s: File name too long", optarg);
 100                         Nflag = 1;
 101                         break;
 102                 case 'M':
 103                         if (strlcpy(corefile, optarg, sizeof(corefile))
 104                             >= sizeof(corefile))
 105                                 errx(1, "%s: File name too long", optarg);
 106                         Mflag = 1;
 107                         break;
 108                 case 'c':
 109                         cflag = strtol(optarg, NULL, 0);
 110                         break;
 111                 case 's':
 112                         sflag = 1;
 113                         break;
 114                 case 'i':
 115                         iflag = 1;
 116                         break;
 117                 case 'n':
 118                         nflag = 1;
 119                         break;
 120                 case 'f':
 121                         fflag = 1;
 122                         break;
 123                 default:
 124                         usage();
 125                 }
 126         }
 127
 128         if (sflag == 0 && iflag == 0) {
 129                 sflag = 1;
 130                 iflag = 1;
 131         }
 132         if (nflag == 0)
 133                 read_symbols(Nflag ? execfile : NULL);
 134
 135         if (fflag && (cflag < 0 || sflag + iflag > 1)) {
 136                 fprintf(stderr, "-f can only be specified with a particular cpu and just one of -i or -s\n");
 137                 exit(1);
 138         }
 139
 140         ac -= optind;
 141         av += optind;
 142         if (ac != 0 && strtod(av[0], NULL) > 0.0) {
 143                 repeat = (int)(strtod(av[0], NULL) * 1000000.0);
 144                 ++av;
 145                 --ac;
 146         } else if (fflag) {
 147                 repeat = 1000000 / 10;
 148         } else {
 149                 repeat = 0;
 150         }
 151         if (ac != 0)
 152                 usage();
 153
 154         /*
 155          * Open our execfile and corefile, resolve needed symbols and read in
 156          * the trace buffer.
 157          */
 158         if ((kd = kvm_openfiles(Nflag ? execfile : NULL,
 159             Mflag ? corefile : NULL, NULL, O_RDONLY, errbuf)) == NULL)
 160                 errx(1, "%s", errbuf);
 161         if (kvm_nlist(kd, nl) != 0)
 162                 errx(1, "%s", kvm_geterr(kd));
 163
 164         if (kvm_read(kd, nl[0].n_value, &ncpus, sizeof(ncpus)) == -1)
 165                 errx(1, "%s", kvm_geterr(kd));
 166         if (kvm_read(kd, nl[1].n_value, &pchead, sizeof(pchead)) == -1)
 167                 errx(1, "%s", kvm_geterr(kd));
 168
 169 again:
 170         for (cpu = 0; cpu < ncpus; ++cpu) {
 171                 for (ntrack = 0; ntrack < pchead.pc_ntrack; ++ntrack) {
 172                         int offset;
 173
 174                         if (ntrack == PCTRACK_SYS && sflag == 0)
 175                                 continue;
 176                         if (ntrack == PCTRACK_INT && iflag == 0)
 177                                 continue;
 178                         if (cflag >= 0 && cflag != cpu)
 179                                 continue;
 180
 181                         offset = offsetof(struct kinfo_pctrack,
 182                                           pc_array[pchead.pc_arysize]);
 183                         offset = (offset * pchead.pc_ntrack * cpu) +
 184                                  (offset * ntrack);
 185                         if (kvm_read(kd, nl[2].n_value + offset, &pctrack, sizeof(pctrack)) < 0)
 186                                 errx(1, "%s", kvm_geterr(kd));
 187
 188                         printf("CPU %d %s:\n", cpu,
 189                                 (ntrack == PCTRACK_SYS) ? "SYSTEM" :
 190                                 (ntrack == PCTRACK_INT) ? "INTERRUPT" : "?"
 191                         );
 192
 193                         do_output(cpu, ntrack, &pchead, &pctrack, pctrack.pc_index - pchead.pc_arysize);
 194                         while (fflag) {
 195                                 usleep(repeat);
 196                                 int last_index = pctrack.pc_index;
 197                                 kvm_read(kd, nl[2].n_value + offset, &pctrack,
 198                                          sizeof(pctrack));
 199                                 do_output(cpu, ntrack, &pchead, &pctrack, last_index);
 200                         }
 201                 }
 202         }
 203         if (repeat) {
 204                 usleep(repeat);
 205                 goto again;
 206         }
 207         return(0);
 208 }
 209
 210 static void
 211 do_output(int cpu __unused, int track __unused, struct kinfo_pcheader *pchead, struct kinfo_pctrack *pctrack, int base_index)
 212 {
 213         int i;
 214
 215         i = base_index;
 216         if (pctrack->pc_index - base_index > pchead->pc_arysize) {
 217                 i = pctrack->pc_index - pchead->pc_arysize;
 218         }
 219         while (i < pctrack->pc_index) {
 220                 void *data = pctrack->pc_array[i & (pchead->pc_arysize - 1)];
 221                 if (nflag)
 222                         printf("\t%p\n", data);
 223                 else
 224                         printf("\t%s\n", address_to_symbol(data));
 225                 ++i;
 226         }
 227 }
 228
 229 struct symdata {
 230         TAILQ_ENTRY(symdata) link;
 231         const char *symname;
 232         char *symaddr;
 233         char symtype;
 234 };
 235
 236 static TAILQ_HEAD(symlist, symdata) symlist;
 237 static struct symdata *symcache;
 238 static char *symbegin;
 239 static char *symend;
 240
 241 static void
 242 read_symbols(const char *file)
 243 {
 244         char buf[256];
 245         char cmd[256];
 246         size_t buflen = sizeof(buf);
 247         FILE *fp;
 248         struct symdata *sym;
 249         char *s1;
 250         char *s2;
 251         char *s3;
 252
 253         TAILQ_INIT(&symlist);
 254
 255         if (file == NULL) {
 256                 if (sysctlbyname("kern.bootfile", buf, &buflen, NULL, 0) < 0)
 257                         file = "/boot/kernel";
 258                 else
 259                         file = buf;
 260         }
 261         snprintf(cmd, sizeof(cmd), "nm -n %s", file);
 262         if ((fp = popen(cmd, "r")) != NULL) {
 263                 while (fgets(buf, sizeof(buf), fp) != NULL) {
 264                     s1 = strtok(buf, " \t\n");
 265                     s2 = strtok(NULL, " \t\n");
 266                     s3 = strtok(NULL, " \t\n");
 267                     if (s1 && s2 && s3) {
 268                         sym = malloc(sizeof(struct symdata));
 269                         sym->symaddr = (char *)strtoul(s1, NULL, 16);
 270                         sym->symtype = s2[0];
 271                         sym->symname = strdup(s3);
 272                         if (strcmp(s3, "kernbase") == 0)
 273                                 symbegin = sym->symaddr;
 274                         if (strcmp(s3, "end") == 0)
 275                                 symend = sym->symaddr;
 276                         TAILQ_INSERT_TAIL(&symlist, sym, link);
 277                     }
 278                 }
 279                 pclose(fp);
 280         }
 281         symcache = TAILQ_FIRST(&symlist);
 282 }
 283
 284 static const char *
 285 address_to_symbol(void *kptr)
 286 {
 287         static char buf[64];
 288
 289         if (symcache == NULL ||
 290            (char *)kptr < symbegin || (char *)kptr >= symend
 291         ) {
 292                 snprintf(buf, sizeof(buf), "%p", kptr);
 293                 return(buf);
 294         }
 295         while ((char *)symcache->symaddr < (char *)kptr) {
 296                 if (TAILQ_NEXT(symcache, link) == NULL)
 297                         break;
 298                 symcache = TAILQ_NEXT(symcache, link);
 299         }
 300         while ((char *)symcache->symaddr > (char *)kptr) {
 301                 if (symcache != TAILQ_FIRST(&symlist))
 302                         symcache = TAILQ_PREV(symcache, symlist, link);
 303         }
 304         snprintf(buf, sizeof(buf), "%s+%d", symcache->symname,
 305                 (int)((char *)kptr - symcache->symaddr));
 306         return(buf);
 307 }
 308
 309 static void
 310 usage(void)
 311 {
 312         fprintf(stderr, "usage: pctrack [-nsi] [-c cpu] [-N execfile] "
 313                         "[-M corefile]\n");
 314         exit(1);
 315 }