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   u_char tag = GMON_TAG_CG_ARC;
 198   struct gmon_cg_arc_record raw_arc
 199     __attribute__ ((aligned (__alignof__ (char*))));
 200   int from_index, to_index, from_len;
 201   u_long frompc;
 202
 203   struct iovec iov[2] =
 204     {
 205       { &tag, sizeof (tag) },
 206       { &raw_arc, sizeof (struct gmon_cg_arc_record) }
 207     };
 208
 209   from_len = _gmonparam.fromssize / sizeof (*_gmonparam.froms);
 210   for (from_index = 0; from_index < from_len; ++from_index)
 211     {
 212       if (_gmonparam.froms[from_index] == 0)
 213         continue;
 214
 215       frompc = _gmonparam.lowpc;
 216       frompc += (from_index * _gmonparam.hashfraction
 217                  * sizeof (*_gmonparam.froms));
 218       for (to_index = _gmonparam.froms[from_index];
 219            to_index != 0;
 220            to_index = _gmonparam.tos[to_index].link)
 221         {
 222           *(char **) raw_arc.from_pc = (char *)frompc;
 223           *(char **) raw_arc.self_pc = (char *)_gmonparam.tos[to_index].selfpc;
 224           *(int *) raw_arc.count = _gmonparam.tos[to_index].count;
 225
 226           __writev (fd, iov, 2);
 227         }
 228     }
 229 }
 230
 231
 232 static void
 233 write_bb_counts (fd)
 234      int fd;
 235 {
 236   struct __bb *grp;
 237   u_char tag = GMON_TAG_BB_COUNT;
 238   int ncounts;
 239   int i;
 240
 241   struct iovec bbhead[2] =
 242     {
 243       { &tag, sizeof (tag) },
 244       { &ncounts, sizeof (ncounts) }
 245     };
 246   struct iovec bbbody[2];
 247
 248   bbbody[0].iov_len = sizeof (grp->addresses[0]);
 249   bbbody[1].iov_len = sizeof (grp->addresses[0]);
 250
 251   /* Write each group of basic-block info (all basic-blocks in a
 252      compilation unit form a single group). */
 253
 254   for (grp = __bb_head; grp; grp = grp->next)
 255     {
 256       ncounts = grp->ncounts;
 257       __writev (fd, bbhead, 2);
 258       for (i = 0; i < ncounts; ++i)
 259         {
 260           bbbody[0].iov_base = (char *) &grp->addresses[i];
 261           bbbody[1].iov_base = &grp->counts[i];
 262           __writev (fd, bbbody, 2);
 263         }
 264     }
 265 }
 266
 267
 268 void
 269 _mcleanup ()
 270 {
 271     struct gmon_hdr ghdr __attribute__ ((aligned (__alignof__ (int))));
 272     int fd;
 273
 274     moncontrol (0);
 275     fd = __open ("gmon.out", O_CREAT|O_TRUNC|O_WRONLY, 0666);
 276     if (fd < 0)
 277       {
 278         perror ("_mcleanup: gmon.out");
 279         return;
 280       }
 281
 282     /* write gmon.out header: */
 283     memset (&ghdr, 0, sizeof (struct gmon_hdr));
 284     memcpy (&ghdr.cookie[0], GMON_MAGIC, sizeof (ghdr.cookie));
 285     *(int *) ghdr.version = GMON_VERSION;
 286     __write (fd, &ghdr, sizeof (struct gmon_hdr));
 287
 288     /* write PC histogram: */
 289     write_hist (fd);
 290
 291     /* write call-graph: */
 292     write_call_graph (fd);
 293
 294     /* write basic-block execution counts: */
 295     write_bb_counts (fd);
 296
 297     __close (fd);
 298 }