usr.sbin/kgmon/kgmon.c

   1 /*      $NetBSD: kgmon.c,v 1.23 2008/07/21 13:36:58 lukem Exp $ */
   2
   3 /*
   4  * Copyright (c) 1983, 1992, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #include <sys/cdefs.h>
  33 #ifndef lint
  34 __COPYRIGHT("@(#) Copyright (c) 1983, 1992, 1993\
  35  The Regents of the University of California.  All rights reserved.");
  36 #endif /* not lint */
  37
  38 #ifndef lint
  39 #if 0
  40 static char sccsid[] = "from: @(#)kgmon.c       8.1 (Berkeley) 6/6/93";
  41 #else
  42 __RCSID("$NetBSD: kgmon.c,v 1.23 2008/07/21 13:36:58 lukem Exp $");
  43 #endif
  44 #endif /* not lint */
  45
  46 #include <sys/param.h>
  47 #include <sys/file.h>
  48 #include <sys/sysctl.h>
  49 #include <sys/gmon.h>
  50
  51 #include <ctype.h>
  52 #include <errno.h>
  53 #include <kvm.h>
  54 #include <err.h>
  55 #include <limits.h>
  56 #include <nlist.h>
  57 #include <stdio.h>
  58 #include <stdlib.h>
  59 #include <string.h>
  60 #include <unistd.h>
  61
  62 static struct nlist nl[] = {
  63 #define N_GMONPARAM     0
  64         { "__gmonparam", 0, 0, 0, 0 },
  65 #define N_PROFHZ        1
  66         { "_profhz", 0, 0, 0, 0 },
  67         { 0, 0, 0, 0, 0 }
  68 };
  69
  70 struct kvmvars {
  71         kvm_t   *kd;
  72         struct gmonparam gpm;
  73 };
  74
  75 static int      bflag, hflag, kflag, rflag, pflag;
  76 static int      debug = 0;
  77 static void     setprof(struct kvmvars *kvp, int state);
  78 static void     dumpstate(struct kvmvars *kvp);
  79 static void     reset(struct kvmvars *kvp);
  80 static int      openfiles(char *, char *, struct kvmvars *);
  81 static int      getprof(struct kvmvars *);
  82 static void     kern_readonly(int);
  83 static int      getprofhz(struct kvmvars *);
  84
  85 int
  86 main(int argc, char **argv)
  87 {
  88         int ch, mode, disp, accessmode;
  89         struct kvmvars kvmvars;
  90         char *sys, *kmemf;
  91
  92         setprogname(argv[0]);
  93         (void)seteuid(getuid());
  94         kmemf = NULL;
  95         sys = NULL;
  96         while ((ch = getopt(argc, argv, "M:N:bdhpr")) != -1) {
  97                 switch((char)ch) {
  98
  99                 case 'M':
 100                         kmemf = optarg;
 101                         kflag = 1;
 102                         break;
 103
 104                 case 'N':
 105                         sys = optarg;
 106                         break;
 107
 108                 case 'b':
 109                         bflag = 1;
 110                         break;
 111
 112                 case 'h':
 113                         hflag = 1;
 114                         break;
 115
 116                 case 'p':
 117                         pflag = 1;
 118                         break;
 119
 120                 case 'r':
 121                         rflag = 1;
 122                         break;
 123
 124                 case 'd':
 125                         debug = 1;
 126                         break;
 127
 128                 default:
 129                         (void)fprintf(stderr,
 130                             "usage: %s [-bdhrp] [-M core] [-N system]\n",
 131                             getprogname());
 132                         exit(1);
 133                 }
 134         }
 135         argc -= optind;
 136         argv += optind;
 137
 138 #define BACKWARD_COMPATIBILITY
 139 #ifdef  BACKWARD_COMPATIBILITY
 140         if (*argv) {
 141                 sys = *argv;
 142                 if (*++argv) {
 143                         kmemf = *argv;
 144                         ++kflag;
 145                 }
 146         }
 147 #endif
 148         accessmode = openfiles(sys, kmemf, &kvmvars);
 149         mode = getprof(&kvmvars);
 150         if (hflag)
 151                 disp = GMON_PROF_OFF;
 152         else if (bflag)
 153                 disp = GMON_PROF_ON;
 154         else
 155                 disp = mode;
 156         if (pflag)
 157                 dumpstate(&kvmvars);
 158         if (rflag)
 159                 reset(&kvmvars);
 160         if (accessmode == O_RDWR)
 161                 setprof(&kvmvars, disp);
 162         (void)fprintf(stdout, "%s: kernel profiling is %s.\n",
 163              getprogname(), disp == GMON_PROF_OFF ? "off" : "running");
 164         return (0);
 165 }
 166
 167 /*
 168  * Check that profiling is enabled and open any ncessary files.
 169  */
 170 static int
 171 openfiles(char *sys, char *kmemf, struct kvmvars *kvp)
 172 {
 173         int mib[3], state, openmode;
 174         size_t size;
 175         char errbuf[_POSIX2_LINE_MAX];
 176
 177         if (!kflag) {
 178                 mib[0] = CTL_KERN;
 179                 mib[1] = KERN_PROF;
 180                 mib[2] = GPROF_STATE;
 181                 size = sizeof state;
 182                 if (sysctl(mib, 3, &state, &size, NULL, 0) < 0)
 183                         err(EXIT_FAILURE, "profiling not defined in kernel");
 184                 if (!(bflag || hflag || rflag ||
 185                     (pflag && state == GMON_PROF_ON)))
 186                         return (O_RDONLY);
 187                 (void)seteuid(0);
 188                 if (sysctl(mib, 3, NULL, NULL, &state, size) >= 0)
 189                         return (O_RDWR);
 190                 (void)seteuid(getuid());
 191                 kern_readonly(state);
 192                 return (O_RDONLY);
 193         }
 194         openmode = (bflag || hflag || pflag || rflag) ? O_RDWR : O_RDONLY;
 195         kvp->kd = kvm_openfiles(sys, kmemf, NULL, openmode, errbuf);
 196         if (kvp->kd == NULL) {
 197                 if (openmode == O_RDWR) {
 198                         openmode = O_RDONLY;
 199                         kvp->kd = kvm_openfiles(sys, kmemf, NULL, O_RDONLY,
 200                             errbuf);
 201                 }
 202                 if (kvp->kd == NULL)
 203                         errx(EXIT_FAILURE, "kvm_openfiles: %s", errbuf);
 204                 kern_readonly(GMON_PROF_ON);
 205         }
 206         if (kvm_nlist(kvp->kd, nl) < 0)
 207                 errx(EXIT_FAILURE, "%s: no namelist", sys);
 208         if (!nl[N_GMONPARAM].n_value)
 209                 errx(EXIT_FAILURE, "profiling not defined in kernel");
 210         return (openmode);
 211 }
 212
 213 /*
 214  * Suppress options that require a writable kernel.
 215  */
 216 static void
 217 kern_readonly(int mode)
 218 {
 219
 220         (void)fprintf(stderr, "%s: kernel read-only: ", getprogname());
 221         if (pflag && mode == GMON_PROF_ON)
 222                 (void)fprintf(stderr, "data may be inconsistent\n");
 223         if (rflag)
 224                 (void)fprintf(stderr, "-r supressed\n");
 225         if (bflag)
 226                 (void)fprintf(stderr, "-b supressed\n");
 227         if (hflag)
 228                 (void)fprintf(stderr, "-h supressed\n");
 229         rflag = bflag = hflag = 0;
 230 }
 231
 232 /*
 233  * Get the state of kernel profiling.
 234  */
 235 static int
 236 getprof(struct kvmvars *kvp)
 237 {
 238         int mib[3];
 239         size_t size;
 240
 241         if (kflag) {
 242                 size = kvm_read(kvp->kd, nl[N_GMONPARAM].n_value, &kvp->gpm,
 243                     sizeof kvp->gpm);
 244         } else {
 245                 mib[0] = CTL_KERN;
 246                 mib[1] = KERN_PROF;
 247                 mib[2] = GPROF_GMONPARAM;
 248                 size = sizeof kvp->gpm;
 249                 if (sysctl(mib, 3, &kvp->gpm, &size, NULL, 0) < 0)
 250                         size = 0;
 251         }
 252         if (size != sizeof kvp->gpm)
 253                 errx(EXIT_FAILURE, "cannot get gmonparam: %s",
 254                     kflag ? kvm_geterr(kvp->kd) : strerror(errno));
 255         return (kvp->gpm.state);
 256 }
 257
 258 /*
 259  * Enable or disable kernel profiling according to the state variable.
 260  */
 261 static void
 262 setprof(struct kvmvars *kvp, int state)
 263 {
 264         struct gmonparam *p = (struct gmonparam *)nl[N_GMONPARAM].n_value;
 265         int mib[3], oldstate;
 266         size_t sz;
 267
 268         sz = sizeof(state);
 269         if (!kflag) {
 270                 mib[0] = CTL_KERN;
 271                 mib[1] = KERN_PROF;
 272                 mib[2] = GPROF_STATE;
 273                 if (sysctl(mib, 3, &oldstate, &sz, NULL, 0) < 0)
 274                         goto bad;
 275                 if (oldstate == state)
 276                         return;
 277                 (void)seteuid(0);
 278                 if (sysctl(mib, 3, NULL, NULL, &state, sz) >= 0) {
 279                         (void)seteuid(getuid());
 280                         return;
 281                 }
 282                 (void)seteuid(getuid());
 283         } else if ((size_t)kvm_write(kvp->kd, (u_long)&p->state, (void *)&state, sz)
 284             == sz)
 285                 return;
 286 bad:
 287         warnx("cannot turn profiling %s", state == GMON_PROF_OFF ?
 288             "off" : "on");
 289 }
 290
 291 /*
 292  * Build the gmon.out file.
 293  */
 294 static void
 295 dumpstate(struct kvmvars *kvp)
 296 {
 297         FILE *fp;
 298         struct rawarc rawarc;
 299         struct tostruct *tos;
 300         u_long frompc;
 301         u_short *froms, *tickbuf;
 302         int mib[3];
 303         size_t i;
 304         struct gmonhdr h;
 305         int fromindex, endfrom, toindex;
 306         size_t kcountsize;
 307
 308         setprof(kvp, GMON_PROF_OFF);
 309         fp = fopen("gmon.out", "w");
 310         if (fp == NULL) {
 311                 warn("cannot open `gmon.out'");
 312                 return;
 313         }
 314
 315         /*
 316          * Build the gmon header and write it to a file.
 317          */
 318         bzero(&h, sizeof(h));
 319         h.lpc = kvp->gpm.lowpc;
 320         h.hpc = kvp->gpm.highpc;
 321         h.ncnt = kvp->gpm.kcountsize + sizeof(h);
 322         h.version = GMONVERSION;
 323         h.profrate = getprofhz(kvp);
 324         if (fwrite(&h, sizeof(h), 1, fp) != 1)
 325                 err(EXIT_FAILURE, "writing header to gmon.out");
 326
 327         kcountsize = (size_t)kvp->gpm.kcountsize;
 328
 329         /*
 330          * Write out the tick buffer.
 331          */
 332         mib[0] = CTL_KERN;
 333         mib[1] = KERN_PROF;
 334         if ((tickbuf = malloc(kcountsize)) == NULL)
 335                 err(EXIT_FAILURE, "Cannot allocate %zu kcount space",
 336                     kcountsize);
 337         if (kflag) {
 338                 i = kvm_read(kvp->kd, (u_long)kvp->gpm.kcount, tickbuf,
 339                     kcountsize);
 340         } else {
 341                 mib[2] = GPROF_COUNT;
 342                 i = kcountsize;
 343                 if (sysctl(mib, 3, tickbuf, &i, NULL, 0) < 0)
 344                         i = 0;
 345         }
 346         if (i != kcountsize)
 347                 errx(EXIT_FAILURE, "read ticks: read %zu, got %zu: %s",
 348                     kcountsize, i,
 349                     kflag ? kvm_geterr(kvp->kd) : strerror(errno));
 350         if ((fwrite(tickbuf, kcountsize, 1, fp)) != 1)
 351                 err(EXIT_FAILURE, "writing tocks to gmon.out");
 352         free(tickbuf);
 353
 354         /*
 355          * Write out the arc info.
 356          */
 357         if ((froms = malloc((size_t)kvp->gpm.fromssize)) == NULL)
 358                 err(EXIT_FAILURE, "cannot allocate %zu froms space",
 359                     (size_t)kvp->gpm.fromssize);
 360         if (kflag) {
 361                 i = kvm_read(kvp->kd, (u_long)kvp->gpm.froms, froms,
 362                     (size_t)kvp->gpm.fromssize);
 363         } else {
 364                 mib[2] = GPROF_FROMS;
 365                 i = kvp->gpm.fromssize;
 366                 if (sysctl(mib, 3, froms, &i, NULL, 0) < 0)
 367                         i = 0;
 368         }
 369         if (i != kvp->gpm.fromssize)
 370                 errx(EXIT_FAILURE, "read froms: read %lu, got %lu: %s",
 371                     kvp->gpm.fromssize, (u_long)i,
 372                     kflag ? kvm_geterr(kvp->kd) : strerror(errno));
 373         if ((tos = malloc((size_t)kvp->gpm.tossize)) == NULL)
 374                 err(EXIT_FAILURE, "cannot allocate %zu tos space",
 375                     (size_t)kvp->gpm.tossize);
 376         if (kflag) {
 377                 i = kvm_read(kvp->kd, (u_long)kvp->gpm.tos, (void *)tos,
 378                     (size_t)kvp->gpm.tossize);
 379         } else {
 380                 mib[2] = GPROF_TOS;
 381                 i = kvp->gpm.tossize;
 382                 if (sysctl(mib, 3, tos, &i, NULL, 0) < 0)
 383                         i = 0;
 384         }
 385         if (i != kvp->gpm.tossize)
 386                 errx(EXIT_FAILURE, "read tos: read %zu, got %zu: %s",
 387                     (size_t)kvp->gpm.tossize, i,
 388                     kflag ? kvm_geterr(kvp->kd) : strerror(errno));
 389         if (debug)
 390                 (void)fprintf(stderr, "%s: lowpc 0x%lx, textsize 0x%lx\n",
 391                      getprogname(), kvp->gpm.lowpc, kvp->gpm.textsize);
 392         endfrom = kvp->gpm.fromssize / sizeof(*froms);
 393         for (fromindex = 0; fromindex < endfrom; ++fromindex) {
 394                 if (froms[fromindex] == 0)
 395                         continue;
 396                 frompc = (u_long)kvp->gpm.lowpc +
 397                     (fromindex * kvp->gpm.hashfraction * sizeof(*froms));
 398                 for (toindex = froms[fromindex]; toindex != 0;
 399                    toindex = tos[toindex].link) {
 400                         if (debug)
 401                             (void)fprintf(stderr,
 402                             "%s: [mcleanup] frompc 0x%lx selfpc 0x%lx count %ld\n",
 403                             getprogname(), frompc, tos[toindex].selfpc,
 404                             tos[toindex].count);
 405                         rawarc.raw_frompc = frompc;
 406                         rawarc.raw_selfpc = (u_long)tos[toindex].selfpc;
 407                         rawarc.raw_count = tos[toindex].count;
 408                         if (fwrite(&rawarc, sizeof(rawarc), 1,fp) != 1){
 409                                 err(EXIT_FAILURE,
 410                                     "writing raw arc to gmon.out");
 411                         }
 412                 }
 413         }
 414         free(tos);
 415         (void)fclose(fp);
 416 }
 417
 418 /*
 419  * Get the profiling rate.
 420  */
 421 static int
 422 getprofhz(struct kvmvars *kvp)
 423 {
 424         int mib[2], profrate;
 425         size_t size;
 426         struct clockinfo clockrate;
 427
 428         if (kflag) {
 429                 profrate = 1;
 430                 if (kvm_read(kvp->kd, nl[N_PROFHZ].n_value, &profrate,
 431                     sizeof profrate) != sizeof profrate)
 432                         warnx("get clockrate: %s", kvm_geterr(kvp->kd));
 433                 return (profrate);
 434         }
 435         mib[0] = CTL_KERN;
 436         mib[1] = KERN_CLOCKRATE;
 437         clockrate.profhz = 1;
 438         size = sizeof clockrate;
 439         if (sysctl(mib, 2, &clockrate, &size, NULL, 0) < 0)
 440                 warn("get clockrate");
 441         return (clockrate.profhz);
 442 }
 443
 444 /*
 445  * Reset the kernel profiling date structures.
 446  */
 447 static void
 448 reset(struct kvmvars *kvp)
 449 {
 450         char *zbuf;
 451         size_t biggest;
 452         int mib[3];
 453
 454         setprof(kvp, GMON_PROF_OFF);
 455
 456         biggest = (size_t)kvp->gpm.kcountsize;
 457         if ((size_t)kvp->gpm.fromssize > biggest)
 458                 biggest = (size_t)kvp->gpm.fromssize;
 459         if ((size_t)kvp->gpm.tossize > biggest)
 460                 biggest = (size_t)kvp->gpm.tossize;
 461         if ((zbuf = malloc(biggest)) == NULL)
 462                 err(EXIT_FAILURE, "cannot allocate zbuf space");
 463         (void)memset(zbuf, 0, biggest);
 464         if (kflag) {
 465                 if ((size_t)kvm_write(kvp->kd, (u_long)kvp->gpm.kcount, zbuf,
 466                     (size_t)kvp->gpm.kcountsize) != kvp->gpm.kcountsize)
 467                         errx(EXIT_FAILURE, "tickbuf zero: %s",
 468                              kvm_geterr(kvp->kd));
 469                 if ((size_t)kvm_write(kvp->kd, (u_long)kvp->gpm.froms, zbuf,
 470                     (size_t)kvp->gpm.fromssize) != kvp->gpm.fromssize)
 471                         errx(EXIT_FAILURE, "froms zero: %s",
 472                              kvm_geterr(kvp->kd));
 473                 if ((size_t)kvm_write(kvp->kd, (u_long)kvp->gpm.tos, zbuf,
 474                     (size_t)kvp->gpm.tossize) != kvp->gpm.tossize)
 475                         errx(EXIT_FAILURE, "tos zero: %s", kvm_geterr(kvp->kd));
 476                 free(zbuf);
 477                 return;
 478         }
 479         (void)seteuid(0);
 480         mib[0] = CTL_KERN;
 481         mib[1] = KERN_PROF;
 482         mib[2] = GPROF_COUNT;
 483         if (sysctl(mib, 3, NULL, NULL, zbuf, (size_t)kvp->gpm.kcountsize) < 0)
 484                 err(EXIT_FAILURE, "tickbuf zero");
 485         mib[2] = GPROF_FROMS;
 486         if (sysctl(mib, 3, NULL, NULL, zbuf, (size_t)kvp->gpm.fromssize) < 0)
 487                 err(EXIT_FAILURE, "froms zero");
 488         mib[2] = GPROF_TOS;
 489         if (sysctl(mib, 3, NULL, NULL, zbuf, (size_t)kvp->gpm.tossize) < 0)
 490                 err(EXIT_FAILURE, "tos zero");
 491         (void)seteuid(getuid());
 492         free(zbuf);
 493 }