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/cdefs.h>
  31
  32 #include <sys/types.h>
  33 #include <sys/ktr.h>
  34 #include <sys/kinfo.h>
  35 #include <sys/mman.h>
  36 #include <sys/stat.h>
  37 #include <sys/queue.h>
  38
  39 #include <err.h>
  40 #include <fcntl.h>
  41 #include <kvm.h>
  42 #include <limits.h>
  43 #include <nlist.h>
  44 #include <stdint.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <string.h>
  48 #include <stddef.h>
  49 #include <unistd.h>
  50
  51 #define SBUFLEN 128
  52
  53 static void usage(void);
  54 static void do_output(int, int, struct kinfo_pcheader *, struct kinfo_pctrack *, int);
  55 static void read_symbols(const char *);
  56 static const char *address_to_symbol(void *);
  57
  58 static struct nlist nl[] = {
  59         { .n_name = "_ncpus" },
  60         { .n_name = "_cputime_pcheader" },
  61         { .n_name = "_cputime_pctrack" },
  62         { .n_name = NULL }
  63 };
  64
  65 static char corefile[PATH_MAX];
  66 static char execfile[PATH_MAX];
  67 static char errbuf[_POSIX2_LINE_MAX];
  68
  69 static int sflag;
  70 static int iflag;
  71 static int nflag;
  72 static int fflag;
  73 static int cflag = -1;
  74 static int Nflag;
  75 static int Mflag;
  76
  77 /*
  78  * Reads the cputime_pctrack[] structure from the kernel and displays
  79  * the results in a human readable format.
  80  */
  81 int
  82 main(int ac, char **av)
  83 {
  84         struct kinfo_pcheader pchead;
  85         struct kinfo_pctrack pctrack;
  86         kvm_t *kd;
  87         int ntrack;
  88         int ncpus;
  89         int cpu;
  90         int repeat;
  91         int c;
  92
  93         /*
  94          * Parse commandline arguments.
  95          */
  96         while ((c = getopt(ac, av, "nsifc:N:M:")) != -1) {
  97                 switch (c) {
  98                 case 'N':
  99                         if (strlcpy(execfile, optarg, sizeof(execfile))
 100                             >= sizeof(execfile))
 101                                 errx(1, "%s: File name too long", optarg);
 102                         Nflag = 1;
 103                         break;
 104                 case 'M':
 105                         if (strlcpy(corefile, optarg, sizeof(corefile))
 106                             >= sizeof(corefile))
 107                                 errx(1, "%s: File name too long", optarg);
 108                         Mflag = 1;
 109                         break;
 110                 case 'c':
 111                         cflag = strtol(optarg, NULL, 0);
 112                         break;
 113                 case 's':
 114                         sflag = 1;
 115                         break;
 116                 case 'i':
 117                         iflag = 1;
 118                         break;
 119                 case 'n':
 120                         nflag = 1;
 121                         break;
 122                 case 'f':
 123                         fflag = 1;
 124                         break;
 125                 default:
 126                         usage();
 127                 }
 128         }
 129
 130         if (sflag == 0 && iflag == 0) {
 131                 sflag = 1;
 132                 iflag = 1;
 133         }
 134         if (nflag == 0)
 135                 read_symbols(Nflag ? execfile : NULL);
 136
 137         if (fflag && (cflag < 0 || sflag + iflag > 1)) {
 138                 fprintf(stderr, "-f can only be specified with a particular cpu and just one of -i or -s\n");
 139                 exit(1);
 140         }
 141
 142         ac -= optind;
 143         av += optind;
 144         if (ac != 0 && strtod(av[0], NULL) > 0.0) {
 145                 repeat = (int)(strtod(av[0], NULL) * 1000000.0);
 146                 ++av;
 147                 --ac;
 148         } else if (fflag) {
 149                 repeat = 1000000 / 10;
 150         } else {
 151                 repeat = 0;
 152         }
 153         if (ac != 0)
 154                 usage();
 155
 156         /*
 157          * Open our execfile and corefile, resolve needed symbols and read in
 158          * the trace buffer.
 159          */
 160         if ((kd = kvm_openfiles(Nflag ? execfile : NULL,
 161             Mflag ? corefile : NULL, NULL, O_RDONLY, errbuf)) == NULL)
 162                 errx(1, "%s", errbuf);
 163         if (kvm_nlist(kd, nl) != 0)
 164                 errx(1, "%s", kvm_geterr(kd));
 165
 166         if (kvm_read(kd, nl[0].n_value, &ncpus, sizeof(ncpus)) == -1)
 167                 errx(1, "%s", kvm_geterr(kd));
 168         if (kvm_read(kd, nl[1].n_value, &pchead, sizeof(pchead)) == -1)
 169                 errx(1, "%s", kvm_geterr(kd));
 170
 171 again:
 172         for (cpu = 0; cpu < ncpus; ++cpu) {
 173                 for (ntrack = 0; ntrack < pchead.pc_ntrack; ++ntrack) {
 174                         int offset;
 175
 176                         if (ntrack == PCTRACK_SYS && sflag == 0)
 177                                 continue;
 178                         if (ntrack == PCTRACK_INT && iflag == 0)
 179                                 continue;
 180                         if (cflag >= 0 && cflag != cpu)
 181                                 continue;
 182
 183                         offset = offsetof(struct kinfo_pctrack,
 184                                           pc_array[pchead.pc_arysize]);
 185                         offset = (offset * pchead.pc_ntrack * cpu) +
 186                                  (offset * ntrack);
 187                         if (kvm_read(kd, nl[2].n_value + offset, &pctrack, sizeof(pctrack)) < 0)
 188                                 errx(1, "%s", kvm_geterr(kd));
 189
 190                         printf("CPU %d %s:\n", cpu,
 191                                 (ntrack == PCTRACK_SYS) ? "SYSTEM" :
 192                                 (ntrack == PCTRACK_INT) ? "INTERRUPT" : "?"
 193                         );
 194
 195                         do_output(cpu, ntrack, &pchead, &pctrack, pctrack.pc_index - pchead.pc_arysize);
 196                         while (fflag) {
 197                                 usleep(repeat);
 198                                 int last_index = pctrack.pc_index;
 199                                 kvm_read(kd, nl[2].n_value + offset, &pctrack,
 200                                          sizeof(pctrack));
 201                                 do_output(cpu, ntrack, &pchead, &pctrack, last_index);
 202                         }
 203                 }
 204         }
 205         if (repeat) {
 206                 usleep(repeat);
 207                 goto again;
 208         }
 209         return(0);
 210 }
 211
 212 static void
 213 do_output(int cpu __unused, int track __unused, struct kinfo_pcheader *pchead, struct kinfo_pctrack *pctrack, int base_index)
 214 {
 215         int i;
 216
 217         i = base_index;
 218         if (pctrack->pc_index - base_index > pchead->pc_arysize) {
 219                 i = pctrack->pc_index - pchead->pc_arysize;
 220         }
 221         while (i < pctrack->pc_index) {
 222                 void *data = pctrack->pc_array[i & (pchead->pc_arysize - 1)];
 223                 if (nflag)
 224                         printf("\t%p\n", data);
 225                 else
 226                         printf("\t%s\n", address_to_symbol(data));
 227                 ++i;
 228         }
 229 }
 230
 231 struct symdata {
 232         TAILQ_ENTRY(symdata) link;
 233         const char *symname;
 234         char *symaddr;
 235         char symtype;
 236 };
 237
 238 static TAILQ_HEAD(symlist, symdata) symlist;
 239 static struct symdata *symcache;
 240 static char *symbegin;
 241 static char *symend;
 242
 243 static void
 244 read_symbols(const char *file)
 245 {
 246         char buf[256];
 247         char cmd[256];
 248         size_t buflen = sizeof(buf);
 249         FILE *fp;
 250         struct symdata *sym;
 251         char *s1;
 252         char *s2;
 253         char *s3;
 254
 255         TAILQ_INIT(&symlist);
 256
 257         if (file == NULL) {
 258                 if (sysctlbyname("kern.bootfile", buf, &buflen, NULL, 0) < 0)
 259                         file = "/boot/kernel";
 260                 else
 261                         file = buf;
 262         }
 263         snprintf(cmd, sizeof(cmd), "nm -n %s", file);
 264         if ((fp = popen(cmd, "r")) != NULL) {
 265                 while (fgets(buf, sizeof(buf), fp) != NULL) {
 266                     s1 = strtok(buf, " \t\n");
 267                     s2 = strtok(NULL, " \t\n");
 268                     s3 = strtok(NULL, " \t\n");
 269                     if (s1 && s2 && s3) {
 270                         sym = malloc(sizeof(struct symdata));
 271                         sym->symaddr = (char *)strtoul(s1, NULL, 16);
 272                         sym->symtype = s2[0];
 273                         sym->symname = strdup(s3);
 274                         if (strcmp(s3, "kernbase") == 0)
 275                                 symbegin = sym->symaddr;
 276                         if (strcmp(s3, "end") == 0)
 277                                 symend = sym->symaddr;
 278                         TAILQ_INSERT_TAIL(&symlist, sym, link);
 279                     }
 280                 }
 281                 pclose(fp);
 282         }
 283         symcache = TAILQ_FIRST(&symlist);
 284 }
 285
 286 static const char *
 287 address_to_symbol(void *kptr)
 288 {
 289         static char buf[64];
 290
 291         if (symcache == NULL ||
 292            (char *)kptr < symbegin || (char *)kptr >= symend
 293         ) {
 294                 snprintf(buf, sizeof(buf), "%p", kptr);
 295                 return(buf);
 296         }
 297         while ((char *)symcache->symaddr < (char *)kptr) {
 298                 if (TAILQ_NEXT(symcache, link) == NULL)
 299                         break;
 300                 symcache = TAILQ_NEXT(symcache, link);
 301         }
 302         while ((char *)symcache->symaddr > (char *)kptr) {
 303                 if (symcache != TAILQ_FIRST(&symlist))
 304                         symcache = TAILQ_PREV(symcache, symlist, link);
 305         }
 306         snprintf(buf, sizeof(buf), "%s+%d", symcache->symname,
 307                 (int)((char *)kptr - symcache->symaddr));
 308         return(buf);
 309 }
 310
 311 static void
 312 usage(void)
 313 {
 314         fprintf(stderr, "usage: pctrack [-nsi] [-c cpu] [-N execfile] "
 315                         "[-M corefile]\n");
 316         exit(1);
 317 }