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 <stdio.h>
  40 #include <fcntl.h>
  41 #include <unistd.h>
  42
  43 #include <stdio.h>
  44 #include <stdlib.h>
  45 #include <string.h>
  46 #include <unistd.h>
  47
  48 extern int __profile_frequency __P ((void));
  49
  50 struct __bb *__bb_head; /*  Head of basic-block list or NULL. */
  51
  52 struct gmonparam _gmonparam = { GMON_PROF_OFF };
  53
  54 /*
  55  * See profil(2) where this is described:
  56  */
  57 static int      s_scale;
  58 #define         SCALE_1_TO_1    0x10000L
  59
  60 #define ERR(s) write(2, s, sizeof(s) - 1)
  61
  62 void moncontrol __P ((int mode));
  63 static void write_hist __P ((int fd));
  64 static void write_call_graph __P ((int fd));
  65 static void write_bb_counts __P ((int fd));
  66
  67 /*
  68  * Control profiling
  69  *      profiling is what mcount checks to see if
  70  *      all the data structures are ready.
  71  */
  72 void
  73 moncontrol (mode)
  74      int mode;
  75 {
  76   struct gmonparam *p = &_gmonparam;
  77
  78   if (mode)
  79     {
  80       /* start */
  81       profil((void *) p->kcount, p->kcountsize, p->lowpc, s_scale);
  82       p->state = GMON_PROF_ON;
  83     }
  84   else
  85     {
  86       /* stop */
  87       profil((void *) 0, 0, 0, 0);
  88       p->state = GMON_PROF_OFF;
  89     }
  90 }
  91
  92
  93 void
  94 monstartup (lowpc, highpc)
  95      u_long lowpc;
  96      u_long highpc;
  97 {
  98   register int o;
  99   char *cp;
 100   struct gmonparam *p = &_gmonparam;
 101
 102   /*
 103    * round lowpc and highpc to multiples of the density we're using
 104    * so the rest of the scaling (here and in gprof) stays in ints.
 105    */
 106   p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
 107   p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
 108   p->textsize = p->highpc - p->lowpc;
 109   p->kcountsize = p->textsize / HISTFRACTION;
 110   p->hashfraction = HASHFRACTION;
 111   p->log_hashfraction = -1;
 112   if ((HASHFRACTION & (HASHFRACTION - 1)) == 0) {
 113       /* if HASHFRACTION is a power of two, mcount can use shifting
 114          instead of integer division.  Precompute shift amount. */
 115       p->log_hashfraction = ffs(p->hashfraction * sizeof(*p->froms)) - 1;
 116   }
 117   p->fromssize = p->textsize / HASHFRACTION;
 118   p->tolimit = p->textsize * ARCDENSITY / 100;
 119   if (p->tolimit < MINARCS)
 120     p->tolimit = MINARCS;
 121   else if (p->tolimit > MAXARCS)
 122     p->tolimit = MAXARCS;
 123   p->tossize = p->tolimit * sizeof(struct tostruct);
 124
 125   cp = malloc (p->kcountsize + p->fromssize + p->tossize);
 126   if (! cp)
 127     {
 128       ERR(_("monstartup: out of memory\n"));
 129       return;
 130     }
 131   bzero(cp, p->kcountsize + p->fromssize + p->tossize);
 132   p->tos = (struct tostruct *)cp;
 133   cp += p->tossize;
 134   p->kcount = (u_short *)cp;
 135   cp += p->kcountsize;
 136   p->froms = (u_short *)cp;
 137
 138   p->tos[0].link = 0;
 139
 140   o = p->highpc - p->lowpc;
 141   if (p->kcountsize < (u_long) o)
 142     {
 143 #ifndef hp300
 144       s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
 145 #else
 146       /* avoid floating point operations */
 147       int quot = o / p->kcountsize;
 148
 149       if (quot >= 0x10000)
 150         s_scale = 1;
 151       else if (quot >= 0x100)
 152         s_scale = 0x10000 / quot;
 153       else if (o >= 0x800000)
 154         s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
 155       else
 156         s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
 157 #endif
 158     } else
 159       s_scale = SCALE_1_TO_1;
 160
 161   moncontrol(1);
 162 }
 163
 164
 165 static void
 166 write_hist (fd)
 167      int fd;
 168 {
 169   u_char tag = GMON_TAG_TIME_HIST;
 170   struct gmon_hist_hdr thdr __attribute__ ((aligned (__alignof__ (char *))));
 171
 172   if (_gmonparam.kcountsize > 0)
 173     {
 174       struct iovec iov[3] =
 175         {
 176           { &tag, sizeof (tag) },
 177           { &thdr, sizeof (struct gmon_hist_hdr) },
 178           { _gmonparam.kcount, _gmonparam.kcountsize }
 179         };
 180
 181       *(char **) thdr.low_pc = (char *) _gmonparam.lowpc;
 182       *(char **) thdr.high_pc = (char *) _gmonparam.highpc;
 183       *(int *) thdr.hist_size = _gmonparam.kcountsize / sizeof (HISTCOUNTER);
 184       *(int *) thdr.prof_rate = __profile_frequency ();
 185       strncpy (thdr.dimen, "seconds", sizeof (thdr.dimen));
 186       thdr.dimen_abbrev = 's';
 187
 188       __writev (fd, iov, 3);
 189     }
 190 }
 191
 192
 193 static void
 194 write_call_graph (fd)
 195      int fd;
 196 {
 197 #define NARCS_PER_WRITEV        32
 198   u_char tag = GMON_TAG_CG_ARC;
 199   struct gmon_cg_arc_record raw_arc[NARCS_PER_WRITEV]
 200     __attribute__ ((aligned (__alignof__ (char*))));
 201   int from_index, to_index, from_len;
 202   u_long frompc;
 203   struct iovec iov[2 * NARCS_PER_WRITEV];
 204   int nfilled;
 205
 206   for (nfilled = 0; nfilled < NARCS_PER_WRITEV; ++nfilled)
 207     {
 208       iov[2 * nfilled].iov_base = &tag;
 209       iov[2 * nfilled].iov_len = sizeof (tag);
 210
 211       iov[2 * nfilled + 1].iov_base = &raw_arc[nfilled];
 212       iov[2 * nfilled + 1].iov_len = sizeof (struct gmon_cg_arc_record);
 213     }
 214
 215   nfilled = 0;
 216   from_len = _gmonparam.fromssize / sizeof (*_gmonparam.froms);
 217   for (from_index = 0; from_index < from_len; ++from_index)
 218     {
 219       if (_gmonparam.froms[from_index] == 0)
 220         continue;
 221
 222       frompc = _gmonparam.lowpc;
 223       frompc += (from_index * _gmonparam.hashfraction
 224                  * sizeof (*_gmonparam.froms));
 225       for (to_index = _gmonparam.froms[from_index];
 226            to_index != 0;
 227            to_index = _gmonparam.tos[to_index].link)
 228         {
 229           *(char **) raw_arc[nfilled].from_pc = (char *) frompc;
 230           *(char **) raw_arc[nfilled].self_pc =
 231             (char *)_gmonparam.tos[to_index].selfpc;
 232           *(int *) raw_arc[nfilled].count = _gmonparam.tos[to_index].count;
 233
 234           if (++nfilled == NARCS_PER_WRITEV)
 235             {
 236               __writev (fd, iov, 2 * nfilled);
 237               nfilled = 0;
 238             }
 239         }
 240     }
 241   if (nfilled > 0)
 242     __writev (fd, iov, 2 * nfilled);
 243 }
 244
 245
 246 static void
 247 write_bb_counts (fd)
 248      int fd;
 249 {
 250   struct __bb *grp;
 251   u_char tag = GMON_TAG_BB_COUNT;
 252   size_t ncounts;
 253   size_t i;
 254
 255   struct iovec bbhead[2] =
 256     {
 257       { &tag, sizeof (tag) },
 258       { &ncounts, sizeof (ncounts) }
 259     };
 260   struct iovec bbbody[8];
 261   size_t nfilled;
 262
 263   for (i = 0; i < (sizeof (bbbody) / sizeof (bbbody[0])); i += 2)
 264     {
 265       bbbody[i].iov_len = sizeof (grp->addresses[0]);
 266       bbbody[i + 1].iov_len = sizeof (grp->counts[0]);
 267     }
 268
 269   /* Write each group of basic-block info (all basic-blocks in a
 270      compilation unit form a single group). */
 271
 272   for (grp = __bb_head; grp; grp = grp->next)
 273     {
 274       ncounts = grp->ncounts;
 275       __writev (fd, bbhead, 2);
 276       for (nfilled = i = 0; i < ncounts; ++i)
 277         {
 278           if (nfilled > (sizeof (bbbody) / sizeof (bbbody[0])) - 2)
 279             {
 280               __writev (fd, bbbody, nfilled);
 281               nfilled = 0;
 282             }
 283
 284           bbbody[nfilled++].iov_base = (char *) &grp->addresses[i];
 285           bbbody[nfilled++].iov_base = &grp->counts[i];
 286         }
 287       if (nfilled > 0)
 288         __writev (fd, bbbody, nfilled);
 289     }
 290 }
 291
 292
 293 void
 294 _mcleanup ()
 295 {
 296     struct gmon_hdr ghdr __attribute__ ((aligned (__alignof__ (int))));
 297     int fd;
 298
 299     moncontrol (0);
 300     fd = __open ("gmon.out", O_CREAT|O_TRUNC|O_WRONLY, 0666);
 301     if (fd < 0)
 302       {
 303         perror ("_mcleanup: gmon.out");
 304         return;
 305       }
 306
 307     /* write gmon.out header: */
 308     memset (&ghdr, 0, sizeof (struct gmon_hdr));
 309     memcpy (&ghdr.cookie[0], GMON_MAGIC, sizeof (ghdr.cookie));
 310     *(int *) ghdr.version = GMON_VERSION;
 311     __write (fd, &ghdr, sizeof (struct gmon_hdr));
 312
 313     /* write PC histogram: */
 314     write_hist (fd);
 315
 316     /* write call-graph: */
 317     write_call_graph (fd);
 318
 319     /* write basic-block execution counts: */
 320     write_bb_counts (fd);
 321
 322     __close (fd);
 323 }