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 char *_strerror_internal __P ((int, char *buf, size_t));
  50
  51 extern int __profile_frequency __P ((void));
  52
  53 struct __bb *__bb_head; /*  Head of basic-block list or NULL. */
  54
  55 struct gmonparam _gmonparam = { GMON_PROF_OFF };
  56
  57 /*
  58  * See profil(2) where this is described:
  59  */
  60 static int      s_scale;
  61 #define         SCALE_1_TO_1    0x10000L
  62
  63 #define ERR(s) write(2, s, sizeof(s) - 1)
  64
  65 void moncontrol __P ((int mode));
  66 void __moncontrol __P ((int mode));
  67 static void write_hist __P ((int fd));
  68 static void write_call_graph __P ((int fd));
  69 static void write_bb_counts __P ((int fd));
  70
  71 /*
  72  * Control profiling
  73  *      profiling is what mcount checks to see if
  74  *      all the data structures are ready.
  75  */
  76 void
  77 __moncontrol (mode)
  78      int mode;
  79 {
  80   struct gmonparam *p = &_gmonparam;
  81
  82   if (mode)
  83     {
  84       /* start */
  85       profil((void *) p->kcount, p->kcountsize, p->lowpc, s_scale);
  86       p->state = GMON_PROF_ON;
  87     }
  88   else
  89     {
  90       /* stop */
  91       profil((void *) 0, 0, 0, 0);
  92       p->state = GMON_PROF_OFF;
  93     }
  94 }
  95
  96
  97 void
  98 __monstartup (lowpc, highpc)
  99      u_long lowpc;
 100      u_long highpc;
 101 {
 102   register int o;
 103   char *cp;
 104   struct gmonparam *p = &_gmonparam;
 105
 106   /*
 107    * round lowpc and highpc to multiples of the density we're using
 108    * so the rest of the scaling (here and in gprof) stays in ints.
 109    */
 110   p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
 111   p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
 112   p->textsize = p->highpc - p->lowpc;
 113   p->kcountsize = p->textsize / HISTFRACTION;
 114   p->hashfraction = HASHFRACTION;
 115   p->log_hashfraction = -1;
 116   if ((HASHFRACTION & (HASHFRACTION - 1)) == 0) {
 117       /* if HASHFRACTION is a power of two, mcount can use shifting
 118          instead of integer division.  Precompute shift amount. */
 119       p->log_hashfraction = ffs(p->hashfraction * sizeof(*p->froms)) - 1;
 120   }
 121   p->fromssize = p->textsize / HASHFRACTION;
 122   p->tolimit = p->textsize * ARCDENSITY / 100;
 123   if (p->tolimit < MINARCS)
 124     p->tolimit = MINARCS;
 125   else if (p->tolimit > MAXARCS)
 126     p->tolimit = MAXARCS;
 127   p->tossize = p->tolimit * sizeof(struct tostruct);
 128
 129   cp = malloc (p->kcountsize + p->fromssize + p->tossize);
 130   if (! cp)
 131     {
 132       ERR(_("monstartup: out of memory\n"));
 133       return;
 134     }
 135   memset (cp, '\0', p->kcountsize + p->fromssize + p->tossize);
 136   p->tos = (struct tostruct *)cp;
 137   cp += p->tossize;
 138   p->kcount = (u_short *)cp;
 139   cp += p->kcountsize;
 140   p->froms = (u_short *)cp;
 141
 142   p->tos[0].link = 0;
 143
 144   o = p->highpc - p->lowpc;
 145   if (p->kcountsize < (u_long) o)
 146     {
 147 #ifndef hp300
 148       s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
 149 #else
 150       /* avoid floating point operations */
 151       int quot = o / p->kcountsize;
 152
 153       if (quot >= 0x10000)
 154         s_scale = 1;
 155       else if (quot >= 0x100)
 156         s_scale = 0x10000 / quot;
 157       else if (o >= 0x800000)
 158         s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
 159       else
 160         s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
 161 #endif
 162     } else
 163       s_scale = SCALE_1_TO_1;
 164
 165   __moncontrol(1);
 166 }
 167 weak_alias(__monstartup, monstartup)
 168
 169
 170 static void
 171 write_hist (fd)
 172      int fd;
 173 {
 174   u_char tag = GMON_TAG_TIME_HIST;
 175   struct gmon_hist_hdr thdr __attribute__ ((aligned (__alignof__ (char *))));
 176
 177   if (_gmonparam.kcountsize > 0)
 178     {
 179       struct iovec iov[3] =
 180         {
 181           { &tag, sizeof (tag) },
 182           { &thdr, sizeof (struct gmon_hist_hdr) },
 183           { _gmonparam.kcount, _gmonparam.kcountsize }
 184         };
 185
 186       *(char **) thdr.low_pc = (char *) _gmonparam.lowpc;
 187       *(char **) thdr.high_pc = (char *) _gmonparam.highpc;
 188       *(int32_t *) thdr.hist_size = (_gmonparam.kcountsize
 189                                      / sizeof (HISTCOUNTER));
 190       *(int32_t *) thdr.prof_rate = __profile_frequency ();
 191       strncpy (thdr.dimen, "seconds", sizeof (thdr.dimen));
 192       thdr.dimen_abbrev = 's';
 193
 194       __writev (fd, iov, 3);
 195     }
 196 }
 197
 198
 199 static void
 200 write_call_graph (fd)
 201      int fd;
 202 {
 203 #define NARCS_PER_WRITEV        32
 204   u_char tag = GMON_TAG_CG_ARC;
 205   struct gmon_cg_arc_record raw_arc[NARCS_PER_WRITEV]
 206     __attribute__ ((aligned (__alignof__ (char*))));
 207   int from_index, to_index, from_len;
 208   u_long frompc;
 209   struct iovec iov[2 * NARCS_PER_WRITEV];
 210   int nfilled;
 211
 212   for (nfilled = 0; nfilled < NARCS_PER_WRITEV; ++nfilled)
 213     {
 214       iov[2 * nfilled].iov_base = &tag;
 215       iov[2 * nfilled].iov_len = sizeof (tag);
 216
 217       iov[2 * nfilled + 1].iov_base = &raw_arc[nfilled];
 218       iov[2 * nfilled + 1].iov_len = sizeof (struct gmon_cg_arc_record);
 219     }
 220
 221   nfilled = 0;
 222   from_len = _gmonparam.fromssize / sizeof (*_gmonparam.froms);
 223   for (from_index = 0; from_index < from_len; ++from_index)
 224     {
 225       if (_gmonparam.froms[from_index] == 0)
 226         continue;
 227
 228       frompc = _gmonparam.lowpc;
 229       frompc += (from_index * _gmonparam.hashfraction
 230                  * sizeof (*_gmonparam.froms));
 231       for (to_index = _gmonparam.froms[from_index];
 232            to_index != 0;
 233            to_index = _gmonparam.tos[to_index].link)
 234         {
 235           *(char **) raw_arc[nfilled].from_pc = (char *) frompc;
 236           *(char **) raw_arc[nfilled].self_pc =
 237             (char *)_gmonparam.tos[to_index].selfpc;
 238           *(int *) raw_arc[nfilled].count = _gmonparam.tos[to_index].count;
 239
 240           if (++nfilled == NARCS_PER_WRITEV)
 241             {
 242               __writev (fd, iov, 2 * nfilled);
 243               nfilled = 0;
 244             }
 245         }
 246     }
 247   if (nfilled > 0)
 248     __writev (fd, iov, 2 * nfilled);
 249 }
 250
 251
 252 static void
 253 write_bb_counts (fd)
 254      int fd;
 255 {
 256   struct __bb *grp;
 257   u_char tag = GMON_TAG_BB_COUNT;
 258   size_t ncounts;
 259   size_t i;
 260
 261   struct iovec bbhead[2] =
 262     {
 263       { &tag, sizeof (tag) },
 264       { &ncounts, sizeof (ncounts) }
 265     };
 266   struct iovec bbbody[8];
 267   size_t nfilled;
 268
 269   for (i = 0; i < (sizeof (bbbody) / sizeof (bbbody[0])); i += 2)
 270     {
 271       bbbody[i].iov_len = sizeof (grp->addresses[0]);
 272       bbbody[i + 1].iov_len = sizeof (grp->counts[0]);
 273     }
 274
 275   /* Write each group of basic-block info (all basic-blocks in a
 276      compilation unit form a single group). */
 277
 278   for (grp = __bb_head; grp; grp = grp->next)
 279     {
 280       ncounts = grp->ncounts;
 281       __writev (fd, bbhead, 2);
 282       for (nfilled = i = 0; i < ncounts; ++i)
 283         {
 284           if (nfilled > (sizeof (bbbody) / sizeof (bbbody[0])) - 2)
 285             {
 286               __writev (fd, bbbody, nfilled);
 287               nfilled = 0;
 288             }
 289
 290           bbbody[nfilled++].iov_base = (char *) &grp->addresses[i];
 291           bbbody[nfilled++].iov_base = &grp->counts[i];
 292         }
 293       if (nfilled > 0)
 294         __writev (fd, bbbody, nfilled);
 295     }
 296 }
 297
 298
 299 void
 300 _mcleanup ()
 301 {
 302     struct gmon_hdr ghdr __attribute__ ((aligned (__alignof__ (int))));
 303     int fd;
 304
 305     __moncontrol (0);
 306     fd = __open ("gmon.out", O_CREAT|O_TRUNC|O_WRONLY, 0666);
 307     if (fd < 0)
 308       {
 309         char buf[300];
 310         int errnum = errno;
 311         fprintf (stderr, "_mcleanup: gmon.out: %s\n",
 312                  _strerror_internal (errnum, buf, sizeof buf));
 313         return;
 314       }
 315
 316     /* write gmon.out header: */
 317     memset (&ghdr, '\0', sizeof (struct gmon_hdr));
 318     memcpy (&ghdr.cookie[0], GMON_MAGIC, sizeof (ghdr.cookie));
 319     *(int32_t *) ghdr.version = GMON_VERSION;
 320     __write (fd, &ghdr, sizeof (struct gmon_hdr));
 321
 322     /* write PC histogram: */
 323     write_hist (fd);
 324
 325     /* write call-graph: */
 326     write_call_graph (fd);
 327
 328     /* write basic-block execution counts: */
 329     write_bb_counts (fd);
 330
 331     /* free the memory. */
 332     free (_gmonparam.tos);
 333
 334     __close (fd);
 335 }