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