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
  38 #include <ansidecl.h>
  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 struct __bb *__bb_head; /*  Head of basic-block list or NULL. */
  49
  50 struct gmonparam _gmonparam = { GMON_PROF_OFF };
  51
  52 /*
  53  * See profil(2) where this is described:
  54  */
  55 static int      s_scale;
  56 #define         SCALE_1_TO_1    0x10000L
  57
  58 #define ERR(s) write(2, s, sizeof(s))
  59
  60 /*
  61  * Discover the tick frequency of the machine if something goes wrong,
  62  * we return 0, an impossible hertz.
  63  */
  64 static int
  65 DEFUN_VOID(hertz)
  66 {
  67   struct itimerval tim;
  68
  69   tim.it_interval.tv_sec = 0;
  70   tim.it_interval.tv_usec = 1;
  71   tim.it_value.tv_sec = 0;
  72   tim.it_value.tv_usec = 0;
  73   setitimer(ITIMER_REAL, &tim, 0);
  74   setitimer(ITIMER_REAL, 0, &tim);
  75   if (tim.it_interval.tv_usec < 2)
  76     return 0;
  77   return (1000000 / tim.it_interval.tv_usec);
  78 }
  79
  80
  81 /*
  82  * Control profiling
  83  *      profiling is what mcount checks to see if
  84  *      all the data structures are ready.
  85  */
  86 void
  87 DEFUN(moncontrol, (mode), int mode)
  88 {
  89   struct gmonparam *p = &_gmonparam;
  90
  91   if (mode)
  92     {
  93       /* start */
  94       profil((void *) p->kcount, p->kcountsize, p->lowpc, s_scale);
  95       p->state = GMON_PROF_ON;
  96     }
  97   else
  98     {
  99       /* stop */
 100       profil((void *) 0, 0, 0, 0);
 101       p->state = GMON_PROF_OFF;
 102     }
 103 }
 104
 105
 106 void
 107 DEFUN(monstartup, (lowpc, highpc), u_long lowpc AND u_long highpc)
 108 {
 109   register int o;
 110   char *cp;
 111   struct gmonparam *p = &_gmonparam;
 112
 113   /*
 114    * round lowpc and highpc to multiples of the density we're using
 115    * so the rest of the scaling (here and in gprof) stays in ints.
 116    */
 117   p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
 118   p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
 119   p->textsize = p->highpc - p->lowpc;
 120   p->kcountsize = p->textsize / HISTFRACTION;
 121   p->hashfraction = HASHFRACTION;
 122   p->log_hashfraction = -1;
 123   if ((HASHFRACTION & (HASHFRACTION - 1)) == 0) {
 124       /* if HASHFRACTION is a power of two, mcount can use shifting
 125          instead of integer division.  Precompute shift amount. */
 126       p->log_hashfraction = ffs(p->hashfraction * sizeof(*p->froms)) - 1;
 127   }
 128   p->fromssize = p->textsize / HASHFRACTION;
 129   p->tolimit = p->textsize * ARCDENSITY / 100;
 130   if (p->tolimit < MINARCS)
 131     p->tolimit = MINARCS;
 132   else if (p->tolimit > MAXARCS)
 133     p->tolimit = MAXARCS;
 134   p->tossize = p->tolimit * sizeof(struct tostruct);
 135
 136   cp = malloc (p->kcountsize + p->fromssize + p->tossize);
 137   if (! cp)
 138     {
 139       ERR("monstartup: out of memory\n");
 140       return;
 141     }
 142   bzero(cp, p->kcountsize + p->fromssize + p->tossize);
 143   p->tos = (struct tostruct *)cp;
 144   cp += p->tossize;
 145   p->kcount = (u_short *)cp;
 146   cp += p->kcountsize;
 147   p->froms = (u_short *)cp;
 148
 149   p->tos[0].link = 0;
 150
 151   o = p->highpc - p->lowpc;
 152   if (p->kcountsize < o)
 153     {
 154 #ifndef hp300
 155       s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
 156 #else
 157       /* avoid floating point operations */
 158       int quot = o / p->kcountsize;
 159
 160       if (quot >= 0x10000)
 161         s_scale = 1;
 162       else if (quot >= 0x100)
 163         s_scale = 0x10000 / quot;
 164       else if (o >= 0x800000)
 165         s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
 166       else
 167         s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
 168 #endif
 169     } else
 170       s_scale = SCALE_1_TO_1;
 171
 172   moncontrol(1);
 173 }
 174
 175
 176 static void
 177 DEFUN(write_hist, (fd), int fd)
 178 {
 179   const u_char tag = GMON_TAG_TIME_HIST;
 180   struct gmon_hist_hdr thdr;
 181   int size, rate;
 182
 183   if (_gmonparam.kcountsize > 0)
 184     {
 185       size = _gmonparam.kcountsize / sizeof(HISTCOUNTER);
 186       rate = hertz();
 187       bcopy(&_gmonparam.lowpc, &thdr.low_pc, sizeof(thdr.low_pc));
 188       bcopy(&_gmonparam.highpc, &thdr.high_pc, sizeof(thdr.high_pc));
 189       bcopy(&size, &thdr.hist_size, sizeof(thdr.hist_size));
 190       bcopy(&rate, &thdr.prof_rate, sizeof(thdr.prof_rate));
 191       strcpy(thdr.dimen, "seconds");
 192       thdr.dimen_abbrev = 's';
 193
 194       write(fd, &tag, sizeof(tag));
 195       write(fd, &thdr, sizeof(thdr));
 196       write(fd, _gmonparam.kcount, _gmonparam.kcountsize);
 197     }
 198 }
 199
 200
 201 static void
 202 DEFUN(write_call_graph, (fd), int fd)
 203 {
 204   const u_char tag = GMON_TAG_CG_ARC;
 205   struct gmon_cg_arc_record raw_arc;
 206   int from_index, to_index, from_len;
 207   u_long frompc;
 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           bcopy(&frompc, &raw_arc.from_pc, sizeof(raw_arc.from_pc));
 223           bcopy(&_gmonparam.tos[to_index].selfpc, &raw_arc.self_pc,
 224                 sizeof(raw_arc.self_pc));
 225           bcopy(&_gmonparam.tos[to_index].count, &raw_arc.count,
 226                 sizeof(raw_arc.count));
 227
 228           write(fd, &tag, sizeof(tag));
 229           write(fd, &raw_arc, sizeof(raw_arc));
 230         }
 231     }
 232 }
 233
 234
 235 static void
 236 DEFUN(write_bb_counts, (fd), int fd)
 237 {
 238   struct __bb *grp;
 239   const u_char tag = GMON_TAG_BB_COUNT;
 240   int ncounts;
 241   int i;
 242
 243   /* Write each group of basic-block info (all basic-blocks in a
 244      compilation unit form a single group). */
 245
 246   for (grp = __bb_head; grp; grp = grp->next)
 247     {
 248       ncounts = grp->ncounts;
 249       write(fd, &tag, sizeof(tag));
 250       write(fd, &ncounts, sizeof(ncounts));
 251       for (i = 0; i < ncounts; ++i)
 252         {
 253           write(fd, &grp->addresses[i], sizeof(grp->addresses[0]));
 254           write(fd, &grp->counts[i], sizeof(grp->counts[0]));
 255         }
 256     }
 257 }
 258
 259
 260 void
 261 DEFUN_VOID(_mcleanup)
 262 {
 263     const int version = GMON_VERSION;
 264     struct gmon_hdr ghdr;
 265     int fd;
 266
 267     moncontrol(0);
 268     fd = open("gmon.out", O_CREAT|O_TRUNC|O_WRONLY, 0666);
 269     if (fd < 0)
 270       {
 271         perror("_mcleanup: gmon.out");
 272         return;
 273       }
 274
 275     /* write gmon.out header: */
 276     bcopy(GMON_MAGIC, &ghdr.cookie[0], 4);
 277     bcopy(&version, &ghdr.version, sizeof(version));
 278     write(fd, &ghdr, sizeof(ghdr));
 279
 280     /* write PC histogram: */
 281     write_hist(fd);
 282
 283     /* write call-graph: */
 284     write_call_graph(fd);
 285
 286     /* write basic-block execution counts: */
 287     write_bb_counts(fd);
 288
 289     close(fd);
 290 }