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  * 4. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29 #include <sys/param.h>
  30 #include <sys/time.h>
  31 #include <sys/gmon.h>
  32 #include <sys/gmon_out.h>
  33 #include <sys/uio.h>
  34
  35 #include <errno.h>
  36 #include <stdio.h>
  37 #include <fcntl.h>
  38 #include <unistd.h>
  39
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42 #include <string.h>
  43 #include <unistd.h>
  44 #include <libc-internal.h>
  45
  46 #ifdef USE_IN_LIBIO
  47 # include <wchar.h>
  48 #endif
  49
  50 /*  Head of basic-block list or NULL. */
  51 struct __bb *__bb_head attribute_hidden;
  52
  53 struct gmonparam _gmonparam attribute_hidden = { GMON_PROF_OFF };
  54
  55 /*
  56  * See profil(2) where this is described:
  57  */
  58 static int      s_scale;
  59 #define         SCALE_1_TO_1    0x10000L
  60
  61 #define ERR(s) __write (STDERR_FILENO, s, sizeof (s) - 1)
  62
  63 void moncontrol __P ((int mode));
  64 void __moncontrol __P ((int mode));
  65 static void write_hist __P ((int fd)) internal_function;
  66 static void write_call_graph __P ((int fd)) internal_function;
  67 static void write_bb_counts __P ((int fd)) internal_function;
  68
  69 /*
  70  * Control profiling
  71  *      profiling is what mcount checks to see if
  72  *      all the data structures are ready.
  73  */
  74 void
  75 __moncontrol (mode)
  76      int mode;
  77 {
  78   struct gmonparam *p = &_gmonparam;
  79
  80   /* Don't change the state if we ran into an error.  */
  81   if (p->state == GMON_PROF_ERROR)
  82     return;
  83
  84   if (mode)
  85     {
  86       /* start */
  87       __profil((void *) p->kcount, p->kcountsize, p->lowpc, s_scale);
  88       p->state = GMON_PROF_ON;
  89     }
  90   else
  91     {
  92       /* stop */
  93       __profil(NULL, 0, 0, 0);
  94       p->state = GMON_PROF_OFF;
  95     }
  96 }
  97 weak_alias (__moncontrol, moncontrol)
  98
  99
 100 void
 101 __monstartup (lowpc, highpc)
 102      u_long lowpc;
 103      u_long highpc;
 104 {
 105   register int o;
 106   char *cp;
 107   struct gmonparam *p = &_gmonparam;
 108
 109   /*
 110    * round lowpc and highpc to multiples of the density we're using
 111    * so the rest of the scaling (here and in gprof) stays in ints.
 112    */
 113   p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
 114   p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
 115   p->textsize = p->highpc - p->lowpc;
 116   p->kcountsize = p->textsize / HISTFRACTION;
 117   p->hashfraction = HASHFRACTION;
 118   p->log_hashfraction = -1;
 119   /* The following test must be kept in sync with the corresponding
 120      test in mcount.c.  */
 121   if ((HASHFRACTION & (HASHFRACTION - 1)) == 0) {
 122       /* if HASHFRACTION is a power of two, mcount can use shifting
 123          instead of integer division.  Precompute shift amount. */
 124       p->log_hashfraction = ffs(p->hashfraction * sizeof(*p->froms)) - 1;
 125   }
 126   p->fromssize = p->textsize / HASHFRACTION;
 127   p->tolimit = p->textsize * ARCDENSITY / 100;
 128   if (p->tolimit < MINARCS)
 129     p->tolimit = MINARCS;
 130   else if (p->tolimit > MAXARCS)
 131     p->tolimit = MAXARCS;
 132   p->tossize = p->tolimit * sizeof(struct tostruct);
 133
 134   cp = calloc (p->kcountsize + p->fromssize + p->tossize, 1);
 135   if (! cp)
 136     {
 137       ERR("monstartup: out of memory\n");
 138       p->tos = NULL;
 139       p->state = GMON_PROF_ERROR;
 140       return;
 141     }
 142   p->tos = (struct tostruct *)cp;
 143   cp += p->tossize;
 144   p->kcount = (HISTCOUNTER *)cp;
 145   cp += p->kcountsize;
 146   p->froms = (ARCINDEX *)cp;
 147
 148   p->tos[0].link = 0;
 149
 150   o = p->highpc - p->lowpc;
 151   if (p->kcountsize < (u_long) o)
 152     {
 153 #ifndef hp300
 154       s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
 155 #else
 156       /* avoid floating point operations */
 157       int quot = o / p->kcountsize;
 158
 159       if (quot >= 0x10000)
 160         s_scale = 1;
 161       else if (quot >= 0x100)
 162         s_scale = 0x10000 / quot;
 163       else if (o >= 0x800000)
 164         s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
 165       else
 166         s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
 167 #endif
 168     } else
 169       s_scale = SCALE_1_TO_1;
 170
 171   __moncontrol(1);
 172 }
 173 weak_alias(__monstartup, monstartup)
 174
 175
 176 static void
 177 internal_function
 178 write_hist (fd)
 179      int fd;
 180 {
 181   u_char tag = GMON_TAG_TIME_HIST;
 182   struct gmon_hist_hdr thdr __attribute__ ((aligned (__alignof__ (char *))));
 183
 184   if (_gmonparam.kcountsize > 0)
 185     {
 186       struct iovec iov[3] =
 187         {
 188           { &tag, sizeof (tag) },
 189           { &thdr, sizeof (struct gmon_hist_hdr) },
 190           { _gmonparam.kcount, _gmonparam.kcountsize }
 191         };
 192
 193       *(char **) thdr.low_pc = (char *) _gmonparam.lowpc;
 194       *(char **) thdr.high_pc = (char *) _gmonparam.highpc;
 195       *(int32_t *) thdr.hist_size = (_gmonparam.kcountsize
 196                                      / sizeof (HISTCOUNTER));
 197       *(int32_t *) thdr.prof_rate = __profile_frequency ();
 198       strncpy (thdr.dimen, "seconds", sizeof (thdr.dimen));
 199       thdr.dimen_abbrev = 's';
 200
 201       __writev (fd, iov, 3);
 202     }
 203 }
 204
 205
 206 static void
 207 internal_function
 208 write_call_graph (fd)
 209      int fd;
 210 {
 211 #define NARCS_PER_WRITEV        32
 212   u_char tag = GMON_TAG_CG_ARC;
 213   struct gmon_cg_arc_record raw_arc[NARCS_PER_WRITEV]
 214     __attribute__ ((aligned (__alignof__ (char*))));
 215   ARCINDEX from_index, to_index;
 216   int from_len;
 217   u_long frompc;
 218   struct iovec iov[2 * NARCS_PER_WRITEV];
 219   int nfilled;
 220
 221   for (nfilled = 0; nfilled < NARCS_PER_WRITEV; ++nfilled)
 222     {
 223       iov[2 * nfilled].iov_base = &tag;
 224       iov[2 * nfilled].iov_len = sizeof (tag);
 225
 226       iov[2 * nfilled + 1].iov_base = &raw_arc[nfilled];
 227       iov[2 * nfilled + 1].iov_len = sizeof (struct gmon_cg_arc_record);
 228     }
 229
 230   nfilled = 0;
 231   from_len = _gmonparam.fromssize / sizeof (*_gmonparam.froms);
 232   for (from_index = 0; from_index < from_len; ++from_index)
 233     {
 234       if (_gmonparam.froms[from_index] == 0)
 235         continue;
 236
 237       frompc = _gmonparam.lowpc;
 238       frompc += (from_index * _gmonparam.hashfraction
 239                  * sizeof (*_gmonparam.froms));
 240       for (to_index = _gmonparam.froms[from_index];
 241            to_index != 0;
 242            to_index = _gmonparam.tos[to_index].link)
 243         {
 244           struct arc
 245             {
 246               char *frompc;
 247               char *selfpc;
 248               int32_t count;
 249             }
 250           arc;
 251
 252           arc.frompc = (char *) frompc;
 253           arc.selfpc = (char *) _gmonparam.tos[to_index].selfpc;
 254           arc.count  = _gmonparam.tos[to_index].count;
 255           memcpy (raw_arc + nfilled, &arc, sizeof (raw_arc [0]));
 256
 257           if (++nfilled == NARCS_PER_WRITEV)
 258             {
 259               __writev (fd, iov, 2 * nfilled);
 260               nfilled = 0;
 261             }
 262         }
 263     }
 264   if (nfilled > 0)
 265     __writev (fd, iov, 2 * nfilled);
 266 }
 267
 268
 269 static void
 270 internal_function
 271 write_bb_counts (fd)
 272      int fd;
 273 {
 274   struct __bb *grp;
 275   u_char tag = GMON_TAG_BB_COUNT;
 276   size_t ncounts;
 277   size_t i;
 278
 279   struct iovec bbhead[2] =
 280     {
 281       { &tag, sizeof (tag) },
 282       { &ncounts, sizeof (ncounts) }
 283     };
 284   struct iovec bbbody[8];
 285   size_t nfilled;
 286
 287   for (i = 0; i < (sizeof (bbbody) / sizeof (bbbody[0])); i += 2)
 288     {
 289       bbbody[i].iov_len = sizeof (grp->addresses[0]);
 290       bbbody[i + 1].iov_len = sizeof (grp->counts[0]);
 291     }
 292
 293   /* Write each group of basic-block info (all basic-blocks in a
 294      compilation unit form a single group). */
 295
 296   for (grp = __bb_head; grp; grp = grp->next)
 297     {
 298       ncounts = grp->ncounts;
 299       __writev (fd, bbhead, 2);
 300       for (nfilled = i = 0; i < ncounts; ++i)
 301         {
 302           if (nfilled > (sizeof (bbbody) / sizeof (bbbody[0])) - 2)
 303             {
 304               __writev (fd, bbbody, nfilled);
 305               nfilled = 0;
 306             }
 307
 308           bbbody[nfilled++].iov_base = (char *) &grp->addresses[i];
 309           bbbody[nfilled++].iov_base = &grp->counts[i];
 310         }
 311       if (nfilled > 0)
 312         __writev (fd, bbbody, nfilled);
 313     }
 314 }
 315
 316
 317 static void
 318 write_gmon (void)
 319 {
 320     struct gmon_hdr ghdr __attribute__ ((aligned (__alignof__ (int))));
 321     int fd = -1;
 322     char *env;
 323
 324 #ifndef O_NOFOLLOW
 325 # define O_NOFOLLOW     0
 326 #endif
 327
 328     env = getenv ("GMON_OUT_PREFIX");
 329     if (env != NULL && !__libc_enable_secure)
 330       {
 331         size_t len = strlen (env);
 332         char buf[len + 20];
 333         sprintf (buf, "%s.%u", env, __getpid ());
 334         fd = __open (buf, O_CREAT|O_TRUNC|O_WRONLY|O_NOFOLLOW, 0666);
 335       }
 336
 337     if (fd == -1)
 338       {
 339         fd = __open ("gmon.out", O_CREAT|O_TRUNC|O_WRONLY|O_NOFOLLOW, 0666);
 340         if (fd < 0)
 341           {
 342             char buf[300];
 343             int errnum = errno;
 344 #ifdef USE_IN_LIBIO
 345             if (_IO_fwide (stderr, 0) > 0)
 346               __fwprintf (stderr, L"_mcleanup: gmon.out: %s\n",
 347                           __strerror_r (errnum, buf, sizeof buf));
 348             else
 349 #endif
 350               fprintf (stderr, "_mcleanup: gmon.out: %s\n",
 351                        __strerror_r (errnum, buf, sizeof buf));
 352             return;
 353           }
 354       }
 355
 356     /* write gmon.out header: */
 357     memset (&ghdr, '\0', sizeof (struct gmon_hdr));
 358     memcpy (&ghdr.cookie[0], GMON_MAGIC, sizeof (ghdr.cookie));
 359     *(int32_t *) ghdr.version = GMON_VERSION;
 360     __write (fd, &ghdr, sizeof (struct gmon_hdr));
 361
 362     /* write PC histogram: */
 363     write_hist (fd);
 364
 365     /* write call-graph: */
 366     write_call_graph (fd);
 367
 368     /* write basic-block execution counts: */
 369     write_bb_counts (fd);
 370
 371     __close (fd);
 372 }
 373
 374
 375 void
 376 __write_profiling (void)
 377 {
 378   int save = _gmonparam.state;
 379   _gmonparam.state = GMON_PROF_OFF;
 380   if (save == GMON_PROF_ON)
 381     write_gmon ();
 382   _gmonparam.state = save;
 383 }
 384 weak_alias (__write_profiling, write_profiling)
 385
 386
 387 void
 388 _mcleanup (void)
 389 {
 390   __moncontrol (0);
 391
 392   if (_gmonparam.state != GMON_PROF_ERROR)
 393     write_gmon ();
 394
 395   /* free the memory. */
 396   if (_gmonparam.tos != NULL)
 397     free (_gmonparam.tos);
 398 }