usr.sbin/kgmon/kgmon.c

   1 /*
   2  * Copyright (c) 1983, 1992, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  * @(#) Copyright (c) 1983, 1992, 1993 The Regents of the University of California.  All rights reserved.
  34  * @(#)kgmon.c  8.1 (Berkeley) 6/6/93
  35  * $FreeBSD: src/usr.sbin/kgmon/kgmon.c,v 1.9 1999/08/28 01:16:42 peter Exp $
  36  * $DragonFly: src/usr.sbin/kgmon/kgmon.c,v 1.7 2008/04/20 13:44:26 swildner Exp $
  37  */
  38
  39 #include <sys/param.h>
  40 #include <sys/file.h>
  41 #include <sys/time.h>
  42 #include <sys/sysctl.h>
  43 #include <sys/gmon.h>
  44 #include <ctype.h>
  45 #include <err.h>
  46 #include <errno.h>
  47 #include <kvm.h>
  48 #include <limits.h>
  49 #include <nlist.h>
  50 #include <paths.h>
  51 #include <stdio.h>
  52 #include <stdlib.h>
  53 #include <string.h>
  54 #include <unistd.h>
  55
  56 struct nlist nl[] = {
  57 #define N_GMONPARAM     0
  58         { "__gmonparam" },
  59         { NULL },
  60 };
  61
  62 struct kvmvars {
  63         kvm_t   *kd;
  64         struct gmonparam gpm;
  65 };
  66
  67 int     Bflag, bflag, hflag, kflag, rflag, pflag;
  68 int     debug = 0;
  69 int     getprof(struct kvmvars *);
  70 void    kern_readonly(int);
  71 int     openfiles(char *, char *, struct kvmvars *);
  72 void    setprof(struct kvmvars *kvp, int state);
  73 void    dumpstate(struct kvmvars *kvp);
  74 void    reset(struct kvmvars *kvp);
  75 static void usage(void);
  76
  77 int
  78 main(int argc, char **argv)
  79 {
  80         int ch, mode, disp, accessmode;
  81         struct kvmvars kvmvars;
  82         char *system, *kmemf;
  83
  84         seteuid(getuid());
  85         kmemf = NULL;
  86         system = NULL;
  87         while ((ch = getopt(argc, argv, "M:N:Bbhpr")) != -1) {
  88                 switch((char)ch) {
  89
  90                 case 'M':
  91                         kmemf = optarg;
  92                         kflag = 1;
  93                         break;
  94
  95                 case 'N':
  96                         system = optarg;
  97                         break;
  98
  99                 case 'B':
 100                         Bflag = 1;
 101                         break;
 102
 103                 case 'b':
 104                         bflag = 1;
 105                         break;
 106
 107                 case 'h':
 108                         hflag = 1;
 109                         break;
 110
 111                 case 'p':
 112                         pflag = 1;
 113                         break;
 114
 115                 case 'r':
 116                         rflag = 1;
 117                         break;
 118
 119                 default:
 120                         usage();
 121                 }
 122         }
 123         argc -= optind;
 124         argv += optind;
 125
 126 #define BACKWARD_COMPATIBILITY
 127 #ifdef  BACKWARD_COMPATIBILITY
 128         if (*argv) {
 129                 system = *argv;
 130                 if (*++argv) {
 131                         kmemf = *argv;
 132                         ++kflag;
 133                 }
 134         }
 135 #endif
 136         if (system == NULL)
 137                 system = (char *)getbootfile();
 138         accessmode = openfiles(system, kmemf, &kvmvars);
 139         mode = getprof(&kvmvars);
 140         if (hflag)
 141                 disp = GMON_PROF_OFF;
 142         else if (Bflag)
 143                 disp = GMON_PROF_HIRES;
 144         else if (bflag)
 145                 disp = GMON_PROF_ON;
 146         else
 147                 disp = mode;
 148         if (pflag)
 149                 dumpstate(&kvmvars);
 150         if (rflag)
 151                 reset(&kvmvars);
 152         if (accessmode == O_RDWR)
 153                 setprof(&kvmvars, disp);
 154         fprintf(stdout, "kgmon: kernel profiling is %s.\n",
 155                       disp == GMON_PROF_OFF ? "off" :
 156                       disp == GMON_PROF_HIRES ? "running (high resolution)" :
 157                       disp == GMON_PROF_ON ? "running" :
 158                       disp == GMON_PROF_BUSY ? "busy" :
 159                       disp == GMON_PROF_ERROR ? "off (error)" :
 160                       "in an unknown state");
 161         return (0);
 162 }
 163
 164 static void
 165 usage(void)
 166 {
 167         fprintf(stderr, "usage: kgmon [-Bbhrp] [-M core] [-N system]\n");
 168         exit(1);
 169 }
 170
 171 /*
 172  * Check that profiling is enabled and open any ncessary files.
 173  */
 174 int
 175 openfiles(char *system, char *kmemf, struct kvmvars *kvp)
 176 {
 177         int mib[3], state, openmode;
 178         size_t size;
 179         char errbuf[_POSIX2_LINE_MAX];
 180
 181         if (!kflag) {
 182                 mib[0] = CTL_KERN;
 183                 mib[1] = KERN_PROF;
 184                 mib[2] = GPROF_STATE;
 185                 size = sizeof state;
 186                 if (sysctl(mib, 3, &state, &size, NULL, 0) < 0)
 187                         errx(20, "profiling not defined in kernel");
 188                 if (!(Bflag || bflag || hflag || rflag ||
 189                     (pflag &&
 190                      (state == GMON_PROF_HIRES || state == GMON_PROF_ON))))
 191                         return (O_RDONLY);
 192                 seteuid(0);
 193                 if (sysctl(mib, 3, NULL, NULL, &state, size) >= 0)
 194                         return (O_RDWR);
 195                 seteuid(getuid());
 196                 kern_readonly(state);
 197                 return (O_RDONLY);
 198         }
 199         openmode = (Bflag || bflag || hflag || pflag || rflag)
 200                    ? O_RDWR : O_RDONLY;
 201         kvp->kd = kvm_openfiles(system, kmemf, NULL, openmode, errbuf);
 202         if (kvp->kd == NULL) {
 203                 if (openmode == O_RDWR) {
 204                         openmode = O_RDONLY;
 205                         kvp->kd = kvm_openfiles(system, kmemf, NULL, O_RDONLY,
 206                             errbuf);
 207                 }
 208                 if (kvp->kd == NULL)
 209                         errx(2, "kvm_openfiles: %s", errbuf);
 210                 kern_readonly(GMON_PROF_ON);
 211         }
 212         if (kvm_nlist(kvp->kd, nl) < 0)
 213                 errx(3, "%s: no namelist", system);
 214         if (!nl[N_GMONPARAM].n_value)
 215                 errx(20, "profiling not defined in kernel");
 216         return (openmode);
 217 }
 218
 219 /*
 220  * Suppress options that require a writable kernel.
 221  */
 222 void
 223 kern_readonly(int mode)
 224 {
 225         fprintf(stderr, "kgmon: kernel read-only: ");
 226         if (pflag && (mode == GMON_PROF_HIRES || mode == GMON_PROF_ON))
 227                 fprintf(stderr, "data may be inconsistent\n");
 228         if (rflag)
 229                 fprintf(stderr, "-r suppressed\n");
 230         if (Bflag)
 231                 fprintf(stderr, "-B suppressed\n");
 232         if (bflag)
 233                 fprintf(stderr, "-b suppressed\n");
 234         if (hflag)
 235                 fprintf(stderr, "-h suppressed\n");
 236         rflag = Bflag = bflag = hflag = 0;
 237 }
 238
 239 /*
 240  * Get the state of kernel profiling.
 241  */
 242 int
 243 getprof(struct kvmvars *kvp)
 244 {
 245         int mib[3];
 246         size_t size;
 247
 248         if (kflag) {
 249                 size = kvm_read(kvp->kd, nl[N_GMONPARAM].n_value, &kvp->gpm,
 250                     sizeof kvp->gpm);
 251         } else {
 252                 mib[0] = CTL_KERN;
 253                 mib[1] = KERN_PROF;
 254                 mib[2] = GPROF_GMONPARAM;
 255                 size = sizeof kvp->gpm;
 256                 if (sysctl(mib, 3, &kvp->gpm, &size, NULL, 0) < 0)
 257                         size = 0;
 258         }
 259         if (size != sizeof kvp->gpm)
 260                 errx(4, "cannot get gmonparam: %s",
 261                     kflag ? kvm_geterr(kvp->kd) : strerror(errno));
 262         return (kvp->gpm.state);
 263 }
 264
 265 /*
 266  * Enable or disable kernel profiling according to the state variable.
 267  */
 268 void
 269 setprof(struct kvmvars *kvp, int state)
 270 {
 271         struct gmonparam *p = (struct gmonparam *)nl[N_GMONPARAM].n_value;
 272         int mib[3], oldstate;
 273         size_t size;
 274
 275         size = sizeof(state);
 276         if (!kflag) {
 277                 mib[0] = CTL_KERN;
 278                 mib[1] = KERN_PROF;
 279                 mib[2] = GPROF_STATE;
 280                 if (sysctl(mib, 3, &oldstate, &size, NULL, 0) < 0)
 281                         goto bad;
 282                 if (oldstate == state)
 283                         return;
 284                 seteuid(0);
 285                 if (sysctl(mib, 3, NULL, NULL, &state, size) >= 0) {
 286                         seteuid(getuid());
 287                         return;
 288                 }
 289                 seteuid(getuid());
 290         } else if (kvm_write(kvp->kd, (u_long)&p->state, (void *)&state, size)
 291                     == size) {
 292                 return;
 293         }
 294 bad:
 295         warnx("warning: cannot turn profiling %s",
 296             state == GMON_PROF_OFF ? "off" : "on");
 297 }
 298
 299 /*
 300  * Build the gmon.out file.
 301  */
 302 void
 303 dumpstate(struct kvmvars *kvp)
 304 {
 305         FILE *fp;
 306         struct rawarc rawarc;
 307         struct tostruct *tos;
 308         u_long frompc;
 309         u_short *froms, *tickbuf;
 310         int mib[3];
 311         size_t i;
 312         struct gmonhdr h;
 313         int fromindex, endfrom, toindex;
 314
 315         setprof(kvp, GMON_PROF_OFF);
 316         fp = fopen("gmon.out", "w");
 317         if (fp == 0) {
 318                 warn("gmon.out");
 319                 return;
 320         }
 321
 322         /*
 323          * Build the gmon header and write it to a file.
 324          */
 325         bzero(&h, sizeof(h));
 326         h.lpc = kvp->gpm.lowpc;
 327         h.hpc = kvp->gpm.highpc;
 328         h.ncnt = kvp->gpm.kcountsize + sizeof(h);
 329         h.version = GMONVERSION;
 330         h.profrate = kvp->gpm.profrate;
 331         fwrite((char *)&h, sizeof(h), 1, fp);
 332
 333         /*
 334          * Write out the tick buffer.
 335          */
 336         mib[0] = CTL_KERN;
 337         mib[1] = KERN_PROF;
 338         if ((tickbuf = (u_short *)malloc(kvp->gpm.kcountsize)) == NULL)
 339                 errx(5, "cannot allocate kcount space");
 340         if (kflag) {
 341                 i = kvm_read(kvp->kd, (u_long)kvp->gpm.kcount, (void *)tickbuf,
 342                     kvp->gpm.kcountsize);
 343         } else {
 344                 mib[2] = GPROF_COUNT;
 345                 i = kvp->gpm.kcountsize;
 346                 if (sysctl(mib, 3, tickbuf, &i, NULL, 0) < 0)
 347                         i = 0;
 348         }
 349         if (i != kvp->gpm.kcountsize)
 350                 errx(6, "read ticks: read %lu, got %zd: %s",
 351                     kvp->gpm.kcountsize, i,
 352                     kflag ? kvm_geterr(kvp->kd) : strerror(errno));
 353         if ((fwrite(tickbuf, kvp->gpm.kcountsize, 1, fp)) != 1)
 354                 err(7, "writing tocks to gmon.out");
 355         free(tickbuf);
 356
 357         /*
 358          * Write out the arc info.
 359          */
 360         if ((froms = (u_short *)malloc(kvp->gpm.fromssize)) == NULL)
 361                 errx(8, "cannot allocate froms space");
 362         if (kflag) {
 363                 i = kvm_read(kvp->kd, (u_long)kvp->gpm.froms, (void *)froms,
 364                     kvp->gpm.fromssize);
 365         } else {
 366                 mib[2] = GPROF_FROMS;
 367                 i = kvp->gpm.fromssize;
 368                 if (sysctl(mib, 3, froms, &i, NULL, 0) < 0)
 369                         i = 0;
 370         }
 371         if (i != kvp->gpm.fromssize)
 372                 errx(9, "read froms: read %lu, got %zd: %s",
 373                     kvp->gpm.fromssize, i,
 374                     kflag ? kvm_geterr(kvp->kd) : strerror(errno));
 375         if ((tos = (struct tostruct *)malloc(kvp->gpm.tossize)) == NULL)
 376                 errx(10, "cannot allocate tos space");
 377         if (kflag) {
 378                 i = kvm_read(kvp->kd, (u_long)kvp->gpm.tos, (void *)tos,
 379                     kvp->gpm.tossize);
 380         } else {
 381                 mib[2] = GPROF_TOS;
 382                 i = kvp->gpm.tossize;
 383                 if (sysctl(mib, 3, tos, &i, NULL, 0) < 0)
 384                         i = 0;
 385         }
 386         if (i != kvp->gpm.tossize)
 387                 errx(11, "read tos: read %lu, got %zd: %s",
 388                     kvp->gpm.tossize, i,
 389                     kflag ? kvm_geterr(kvp->kd) : strerror(errno));
 390         if (debug)
 391                 warnx("lowpc 0x%tx, textsize 0x%lx",
 392                               kvp->gpm.lowpc, kvp->gpm.textsize);
 393         endfrom = kvp->gpm.fromssize / sizeof(*froms);
 394         for (fromindex = 0; fromindex < endfrom; ++fromindex) {
 395                 if (froms[fromindex] == 0)
 396                         continue;
 397                 frompc = (u_long)kvp->gpm.lowpc +
 398                     (fromindex * kvp->gpm.hashfraction * sizeof(*froms));
 399                 for (toindex = froms[fromindex]; toindex != 0;
 400                    toindex = tos[toindex].link) {
 401                         if (debug)
 402                             warnx("[mcleanup] frompc 0x%lx selfpc 0x%lx count %ld",
 403                             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                         fwrite((char *)&rawarc, sizeof(rawarc), 1, fp);
 409                 }
 410         }
 411         fclose(fp);
 412 }
 413
 414 /*
 415  * Reset the kernel profiling date structures.
 416  */
 417 void
 418 reset(struct kvmvars *kvp)
 419 {
 420         char *zbuf;
 421         u_long biggest;
 422         int mib[3];
 423
 424         setprof(kvp, GMON_PROF_OFF);
 425
 426         biggest = kvp->gpm.kcountsize;
 427         if (kvp->gpm.fromssize > biggest)
 428                 biggest = kvp->gpm.fromssize;
 429         if (kvp->gpm.tossize > biggest)
 430                 biggest = kvp->gpm.tossize;
 431         if ((zbuf = (char *)malloc(biggest)) == NULL)
 432                 errx(12, "cannot allocate zbuf space");
 433         bzero(zbuf, biggest);
 434         if (kflag) {
 435                 if (kvm_write(kvp->kd, (u_long)kvp->gpm.kcount, zbuf,
 436                     kvp->gpm.kcountsize) != kvp->gpm.kcountsize)
 437                         errx(13, "tickbuf zero: %s", kvm_geterr(kvp->kd));
 438                 if (kvm_write(kvp->kd, (u_long)kvp->gpm.froms, zbuf,
 439                     kvp->gpm.fromssize) != kvp->gpm.fromssize)
 440                         errx(14, "froms zero: %s", kvm_geterr(kvp->kd));
 441                 if (kvm_write(kvp->kd, (u_long)kvp->gpm.tos, zbuf,
 442                     kvp->gpm.tossize) != kvp->gpm.tossize)
 443                         errx(15, "tos zero: %s", kvm_geterr(kvp->kd));
 444                 return;
 445         }
 446         seteuid(0);
 447         mib[0] = CTL_KERN;
 448         mib[1] = KERN_PROF;
 449         mib[2] = GPROF_COUNT;
 450         if (sysctl(mib, 3, NULL, NULL, zbuf, kvp->gpm.kcountsize) < 0)
 451                 err(13, "tickbuf zero");
 452         mib[2] = GPROF_FROMS;
 453         if (sysctl(mib, 3, NULL, NULL, zbuf, kvp->gpm.fromssize) < 0)
 454                 err(14, "froms zero");
 455         mib[2] = GPROF_TOS;
 456         if (sysctl(mib, 3, NULL, NULL, zbuf, kvp->gpm.tossize) < 0)
 457                 err(15, "tos zero");
 458         seteuid(getuid());
 459         free(zbuf);
 460 }