gmon/gmon.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 #include <sys/param.h>
  34 #include <sys/time.h>
  35 #include <sys/gmon.h>
  36 #include <sys/gmon_out.h>
  37 #include <sys/uio.h>
  38
  39 #include <errno.h>
  40 #include <stdio.h>
  41 #include <fcntl.h>
  42 #include <unistd.h>
  43
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <string.h>
  47 #include <unistd.h>
  48
  49 extern int __profile_frequency __P ((void));
  50
  51 struct __bb *__bb_head; /*  Head of basic-block list or NULL. */
  52
  53 struct gmonparam _gmonparam = { GMON_PROF_OFF };
  54
  55 /*
  56  * See profil(2) where this is described:
  57  */
  58 static int      s_scale;
  59 #define         SCALE_1_TO_1    0x10000L
  60
  61 #define ERR(s) __write(2, s, sizeof(s) - 1)
  62
  63 void moncontrol __P ((int mode));
  64 void __moncontrol __P ((int mode));
  65 static void write_hist __P ((int fd)) internal_function;
  66 static void write_call_graph __P ((int fd)) internal_function;
  67 static void write_bb_counts __P ((int fd)) internal_function;
  68
  69 /*
  70  * Control profiling
  71  *      profiling is what mcount checks to see if
  72  *      all the data structures are ready.
  73  */
  74 void
  75 __moncontrol (mode)
  76      int mode;
  77 {
  78   struct gmonparam *p = &_gmonparam;
  79
  80   /* Don't change the state if we ran into an error.  */
  81   if (p->state == GMON_PROF_ERROR)
  82     return;
  83
  84   if (mode)
  85     {
  86       /* start */
  87       __profil((void *) p->kcount, p->kcountsize, p->lowpc, s_scale);
  88       p->state = GMON_PROF_ON;
  89     }
  90   else
  91     {
  92       /* stop */
  93       __profil(NULL, 0, 0, 0);
  94       p->state = GMON_PROF_OFF;
  95     }
  96 }
  97
  98
  99 void
 100 __monstartup (lowpc, highpc)
 101      u_long lowpc;
 102      u_long highpc;
 103 {
 104   register int o;
 105   char *cp;
 106   struct gmonparam *p = &_gmonparam;
 107
 108   /*
 109    * round lowpc and highpc to multiples of the density we're using
 110    * so the rest of the scaling (here and in gprof) stays in ints.
 111    */
 112   p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
 113   p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
 114   p->textsize = p->highpc - p->lowpc;
 115   p->kcountsize = p->textsize / HISTFRACTION;
 116   p->hashfraction = HASHFRACTION;
 117   p->log_hashfraction = -1;
 118   /* The following test must be kept in sync with the corresponding
 119      test in mcount.c.  */
 120   if ((HASHFRACTION & (HASHFRACTION - 1)) == 0) {
 121       /* if HASHFRACTION is a power of two, mcount can use shifting
 122          instead of integer division.  Precompute shift amount. */
 123       p->log_hashfraction = ffs(p->hashfraction * sizeof(*p->froms)) - 1;
 124   }
 125   p->fromssize = p->textsize / HASHFRACTION;
 126   p->tolimit = p->textsize * ARCDENSITY / 100;
 127   if (p->tolimit < MINARCS)
 128     p->tolimit = MINARCS;
 129   else if (p->tolimit > MAXARCS)
 130     p->tolimit = MAXARCS;
 131   p->tossize = p->tolimit * sizeof(struct tostruct);
 132
 133   cp = calloc (p->kcountsize + p->fromssize + p->tossize, 1);
 134   if (! cp)
 135     {
 136       ERR("monstartup: out of memory\n");
 137       p->tos = NULL;
 138       p->state = GMON_PROF_ERROR;
 139       return;
 140     }
 141   p->tos = (struct tostruct *)cp;
 142   cp += p->tossize;
 143   p->kcount = (u_short *)cp;
 144   cp += p->kcountsize;
 145   p->froms = (u_short *)cp;
 146
 147   p->tos[0].link = 0;
 148
 149   o = p->highpc - p->lowpc;
 150   if (p->kcountsize < (u_long) o)
 151     {
 152 #ifndef hp300
 153       s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
 154 #else
 155       /* avoid floating point operations */
 156       int quot = o / p->kcountsize;
 157
 158       if (quot >= 0x10000)
 159         s_scale = 1;
 160       else if (quot >= 0x100)
 161         s_scale = 0x10000 / quot;
 162       else if (o >= 0x800000)
 163         s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
 164       else
 165         s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
 166 #endif
 167     } else
 168       s_scale = SCALE_1_TO_1;
 169
 170   __moncontrol(1);
 171 }
 172 weak_alias(__monstartup, monstartup)
 173
 174
 175 static void
 176 internal_function
 177 write_hist (fd)
 178      int fd;
 179 {
 180   u_char tag = GMON_TAG_TIME_HIST;
 181   struct gmon_hist_hdr thdr __attribute__ ((aligned (__alignof__ (char *))));
 182
 183   if (_gmonparam.kcountsize > 0)
 184     {
 185       struct iovec iov[3] =
 186         {
 187           { &tag, sizeof (tag) },
 188           { &thdr, sizeof (struct gmon_hist_hdr) },
 189           { _gmonparam.kcount, _gmonparam.kcountsize }
 190         };
 191
 192       *(char **) thdr.low_pc = (char *) _gmonparam.lowpc;
 193       *(char **) thdr.high_pc = (char *) _gmonparam.highpc;
 194       *(int32_t *) thdr.hist_size = (_gmonparam.kcountsize
 195                                      / sizeof (HISTCOUNTER));
 196       *(int32_t *) thdr.prof_rate = __profile_frequency ();
 197       strncpy (thdr.dimen, "seconds", sizeof (thdr.dimen));
 198       thdr.dimen_abbrev = 's';
 199
 200       __writev (fd, iov, 3);
 201     }
 202 }
 203
 204
 205 static void
 206 internal_function
 207 write_call_graph (fd)
 208      int fd;
 209 {
 210 #define NARCS_PER_WRITEV        32
 211   u_char tag = GMON_TAG_CG_ARC;
 212   struct gmon_cg_arc_record raw_arc[NARCS_PER_WRITEV]
 213     __attribute__ ((aligned (__alignof__ (char*))));
 214   int from_index, to_index, from_len;
 215   u_long frompc;
 216   struct iovec iov[2 * NARCS_PER_WRITEV];
 217   int nfilled;
 218
 219   for (nfilled = 0; nfilled < NARCS_PER_WRITEV; ++nfilled)
 220     {
 221       iov[2 * nfilled].iov_base = &tag;
 222       iov[2 * nfilled].iov_len = sizeof (tag);
 223
 224       iov[2 * nfilled + 1].iov_base = &raw_arc[nfilled];
 225       iov[2 * nfilled + 1].iov_len = sizeof (struct gmon_cg_arc_record);
 226     }
 227
 228   nfilled = 0;
 229   from_len = _gmonparam.fromssize / sizeof (*_gmonparam.froms);
 230   for (from_index = 0; from_index < from_len; ++from_index)
 231     {
 232       if (_gmonparam.froms[from_index] == 0)
 233         continue;
 234
 235       frompc = _gmonparam.lowpc;
 236       frompc += (from_index * _gmonparam.hashfraction
 237                  * sizeof (*_gmonparam.froms));
 238       for (to_index = _gmonparam.froms[from_index];
 239            to_index != 0;
 240            to_index = _gmonparam.tos[to_index].link)
 241         {
 242           *(char **) raw_arc[nfilled].from_pc = (char *) frompc;
 243           *(char **) raw_arc[nfilled].self_pc =
 244             (char *)_gmonparam.tos[to_index].selfpc;
 245           *(int *) raw_arc[nfilled].count = _gmonparam.tos[to_index].count;
 246
 247           if (++nfilled == NARCS_PER_WRITEV)
 248             {
 249               __writev (fd, iov, 2 * nfilled);
 250               nfilled = 0;
 251             }
 252         }
 253     }
 254   if (nfilled > 0)
 255     __writev (fd, iov, 2 * nfilled);
 256 }
 257
 258
 259 static void
 260 internal_function
 261 write_bb_counts (fd)
 262      int fd;
 263 {
 264   struct __bb *grp;
 265   u_char tag = GMON_TAG_BB_COUNT;
 266   size_t ncounts;
 267   size_t i;
 268
 269   struct iovec bbhead[2] =
 270     {
 271       { &tag, sizeof (tag) },
 272       { &ncounts, sizeof (ncounts) }
 273     };
 274   struct iovec bbbody[8];
 275   size_t nfilled;
 276
 277   for (i = 0; i < (sizeof (bbbody) / sizeof (bbbody[0])); i += 2)
 278     {
 279       bbbody[i].iov_len = sizeof (grp->addresses[0]);
 280       bbbody[i + 1].iov_len = sizeof (grp->counts[0]);
 281     }
 282
 283   /* Write each group of basic-block info (all basic-blocks in a
 284      compilation unit form a single group). */
 285
 286   for (grp = __bb_head; grp; grp = grp->next)
 287     {
 288       ncounts = grp->ncounts;
 289       __writev (fd, bbhead, 2);
 290       for (nfilled = i = 0; i < ncounts; ++i)
 291         {
 292           if (nfilled > (sizeof (bbbody) / sizeof (bbbody[0])) - 2)
 293             {
 294               __writev (fd, bbbody, nfilled);
 295               nfilled = 0;
 296             }
 297
 298           bbbody[nfilled++].iov_base = (char *) &grp->addresses[i];
 299           bbbody[nfilled++].iov_base = &grp->counts[i];
 300         }
 301       if (nfilled > 0)
 302         __writev (fd, bbbody, nfilled);
 303     }
 304 }
 305
 306
 307 static void
 308 write_gmon (void)
 309 {
 310     struct gmon_hdr ghdr __attribute__ ((aligned (__alignof__ (int))));
 311     int fd = -1;
 312     char *env;
 313
 314     env = getenv ("GMON_OUT_PREFIX");
 315     if (env != NULL && !__libc_enable_secure)
 316       {
 317         size_t len = strlen (env);
 318         char buf[len + 20];
 319         sprintf (buf, "%s.%u", env, __getpid ());
 320         fd = __open (buf, O_CREAT|O_TRUNC|O_WRONLY, 0666);
 321       }
 322
 323     if (fd == -1)
 324       {
 325         fd = __open ("gmon.out", O_CREAT|O_TRUNC|O_WRONLY, 0666);
 326         if (fd < 0)
 327           {
 328             char buf[300];
 329             int errnum = errno;
 330             fprintf (stderr, "_mcleanup: gmon.out: %s\n",
 331                      __strerror_r (errnum, buf, sizeof buf));
 332             return;
 333           }
 334       }
 335
 336     /* write gmon.out header: */
 337     memset (&ghdr, '\0', sizeof (struct gmon_hdr));
 338     memcpy (&ghdr.cookie[0], GMON_MAGIC, sizeof (ghdr.cookie));
 339     *(int32_t *) ghdr.version = GMON_VERSION;
 340     __write (fd, &ghdr, sizeof (struct gmon_hdr));
 341
 342     /* write PC histogram: */
 343     write_hist (fd);
 344
 345     /* write call-graph: */
 346     write_call_graph (fd);
 347
 348     /* write basic-block execution counts: */
 349     write_bb_counts (fd);
 350
 351     __close (fd);
 352 }
 353
 354
 355 void
 356 __write_profiling (void)
 357 {
 358   int save = _gmonparam.state;
 359   _gmonparam.state = GMON_PROF_OFF;
 360   if (save == GMON_PROF_ON)
 361     write_gmon ();
 362   _gmonparam.state = save;
 363 }
 364 weak_alias (__write_profiling, write_profiling)
 365
 366
 367 void
 368 _mcleanup (void)
 369 {
 370   __moncontrol (0);
 371
 372   if (_gmonparam.state != GMON_PROF_ERROR)
 373     write_gmon ();
 374
 375   /* free the memory. */
 376   if (_gmonparam.tos != NULL)
 377     free (_gmonparam.tos);
 378 }