ext/Devel/DProf/DProf.xs

   1 #define PERL_NO_GET_CONTEXT
   2 #include "EXTERN.h"
   3 #include "perl.h"
   4 #include "XSUB.h"
   5
   6 /* For older Perls */
   7 #ifndef dTHR
   8 #  define dTHR int dummy_thr
   9 #endif  /* dTHR */
  10
  11 /*#define DBG_SUB 1      */
  12 /*#define DBG_TIMER 1    */
  13
  14 #ifdef DBG_SUB
  15 #  define DBG_SUB_NOTIFY(A,B) warn(A, B)
  16 #else
  17 #  define DBG_SUB_NOTIFY(A,B)  /* nothing */
  18 #endif
  19
  20 #ifdef DBG_TIMER
  21 #  define DBG_TIMER_NOTIFY(A) warn(A)
  22 #else
  23 #  define DBG_TIMER_NOTIFY(A)  /* nothing */
  24 #endif
  25
  26 /* HZ == clock ticks per second */
  27 #ifdef VMS
  28 #  define HZ ((I32)CLK_TCK)
  29 #  define DPROF_HZ HZ
  30 #  include <starlet.h>  /* prototype for sys$gettim() */
  31 #  define Times(ptr) (dprof_times(aTHX_ ptr))
  32 #else
  33 #  ifndef HZ
  34 #    ifdef CLK_TCK
  35 #      define HZ ((I32)CLK_TCK)
  36 #    else
  37 #      define HZ 60
  38 #    endif
  39 #  endif
  40 #  ifdef OS2                            /* times() has significant overhead */
  41 #    define Times(ptr) (dprof_times(aTHX_ ptr))
  42 #    define INCL_DOSPROFILE
  43 #    define INCL_DOSERRORS
  44 #    include <os2.h>
  45 #    define toLongLong(arg) (*(long long*)&(arg))
  46 #    define DPROF_HZ g_dprof_ticks
  47 #  else
  48 #    define Times(ptr) (times(ptr))
  49 #    define DPROF_HZ HZ
  50 #  endif
  51 #endif
  52
  53 XS(XS_Devel__DProf_END);        /* used by prof_mark() */
  54
  55 /* Everything is built on times(2).  See its manpage for a description
  56  * of the timings.
  57  */
  58
  59 union prof_any {
  60         clock_t tms_utime;  /* cpu time spent in user space */
  61         clock_t tms_stime;  /* cpu time spent in system */
  62         clock_t realtime;   /* elapsed real time, in ticks */
  63         char *name;
  64         U32 id;
  65         opcode ptype;
  66 };
  67
  68 typedef union prof_any PROFANY;
  69
  70 typedef struct {
  71     U32         dprof_ticks;
  72     char*       out_file_name;  /* output file (defaults to tmon.out) */
  73     PerlIO*     fp;             /* pointer to tmon.out file */
  74     long        TIMES_LOCATION; /* Where in the file to store the time totals */
  75     int         SAVE_STACK;     /* How much data to buffer until end of run */
  76     int         prof_pid;       /* pid of profiled process */
  77     struct tms  prof_start;
  78     struct tms  prof_end;
  79     clock_t     rprof_start;    /* elapsed real time ticks */
  80     clock_t     rprof_end;
  81     clock_t     wprof_u;
  82     clock_t     wprof_s;
  83     clock_t     wprof_r;
  84     clock_t     otms_utime;
  85     clock_t     otms_stime;
  86     clock_t     orealtime;
  87     PROFANY*    profstack;
  88     int         profstack_max;
  89     int         profstack_ix;
  90     HV*         cv_hash;
  91     U32         total;
  92     U32         lastid;
  93     U32         default_perldb;
  94     U32         depth;
  95 #ifdef OS2
  96     ULONG       frequ;
  97     long long   start_cnt;
  98 #endif
  99 #ifdef PERL_IMPLICIT_CONTEXT
 100 #  define register
 101     pTHX;
 102 #  undef register
 103 #endif
 104 } prof_state_t;
 105
 106 prof_state_t g_prof_state;
 107
 108 #define g_dprof_ticks           g_prof_state.dprof_ticks
 109 #define g_out_file_name         g_prof_state.out_file_name
 110 #define g_fp                    g_prof_state.fp
 111 #define g_TIMES_LOCATION        g_prof_state.TIMES_LOCATION
 112 #define g_SAVE_STACK            g_prof_state.SAVE_STACK
 113 #define g_prof_pid              g_prof_state.prof_pid
 114 #define g_prof_start            g_prof_state.prof_start
 115 #define g_prof_end              g_prof_state.prof_end
 116 #define g_rprof_start           g_prof_state.rprof_start
 117 #define g_rprof_end             g_prof_state.rprof_end
 118 #define g_wprof_u               g_prof_state.wprof_u
 119 #define g_wprof_s               g_prof_state.wprof_s
 120 #define g_wprof_r               g_prof_state.wprof_r
 121 #define g_otms_utime            g_prof_state.otms_utime
 122 #define g_otms_stime            g_prof_state.otms_stime
 123 #define g_orealtime             g_prof_state.orealtime
 124 #define g_profstack             g_prof_state.profstack
 125 #define g_profstack_max         g_prof_state.profstack_max
 126 #define g_profstack_ix          g_prof_state.profstack_ix
 127 #define g_cv_hash               g_prof_state.cv_hash
 128 #define g_total                 g_prof_state.total
 129 #define g_lastid                g_prof_state.lastid
 130 #define g_default_perldb        g_prof_state.default_perldb
 131 #define g_depth                 g_prof_state.depth
 132 #ifdef PERL_IMPLICIT_CONTEXT
 133 #  define g_THX                 g_prof_state.aTHX
 134 #endif
 135 #ifdef OS2
 136 #  define g_frequ               g_prof_state.frequ
 137 #  define g_start_cnt           g_prof_state.start_cnt
 138 #endif
 139
 140 clock_t
 141 dprof_times(pTHX_ struct tms *t)
 142 {
 143 #ifdef OS2
 144     ULONG rc;
 145     QWORD cnt;
 146
 147     if (!g_frequ) {
 148         if (CheckOSError(DosTmrQueryFreq(&g_frequ)))
 149             croak("DosTmrQueryFreq: %s", SvPV(perl_get_sv("!",TRUE),na));
 150         else
 151             g_frequ = g_frequ/DPROF_HZ; /* count per tick */
 152         if (CheckOSError(DosTmrQueryTime(&cnt)))
 153             croak("DosTmrQueryTime: %s",
 154                   SvPV(perl_get_sv("!",TRUE),na));
 155         g_start_cnt = toLongLong(cnt);
 156     }
 157
 158     if (CheckOSError(DosTmrQueryTime(&cnt)))
 159             croak("DosTmrQueryTime: %s", SvPV(perl_get_sv("!",TRUE),na));
 160     t->tms_stime = 0;
 161     return (t->tms_utime = (toLongLong(cnt) - g_start_cnt)/g_frequ);
 162 #else           /* !OS2 */
 163 #  ifdef VMS
 164     clock_t retval;
 165     /* Get wall time and convert to 10 ms intervals to
 166      * produce the return value dprof expects */
 167 #    if defined(__DECC) && defined (__ALPHA)
 168 #      include <ints.h>
 169     uint64 vmstime;
 170     _ckvmssts(sys$gettim(&vmstime));
 171     vmstime /= 100000;
 172     retval = vmstime & 0x7fffffff;
 173 #    else
 174     /* (Older hw or ccs don't have an atomic 64-bit type, so we
 175      * juggle 32-bit ints (and a float) to produce a time_t result
 176      * with minimal loss of information.) */
 177     long int vmstime[2],remainder,divisor = 100000;
 178     _ckvmssts(sys$gettim((unsigned long int *)vmstime));
 179     vmstime[1] &= 0x7fff;  /* prevent overflow in EDIV */
 180     _ckvmssts(lib$ediv(&divisor,vmstime,(long int *)&retval,&remainder));
 181 #    endif
 182     /* Fill in the struct tms using the CRTL routine . . .*/
 183     times((tbuffer_t *)t);
 184     return (clock_t) retval;
 185 #  else         /* !VMS && !OS2 */
 186     return times(t);
 187 #  endif
 188 #endif
 189 }
 190
 191 static void
 192 prof_dumpa(pTHX_ opcode ptype, U32 id)
 193 {
 194     if (ptype == OP_LEAVESUB) {
 195         PerlIO_printf(g_fp,"- %"UVxf"\n", (UV)id);
 196     }
 197     else if(ptype == OP_ENTERSUB) {
 198         PerlIO_printf(g_fp,"+ %"UVxf"\n", (UV)id);
 199     }
 200     else if(ptype == OP_GOTO) {
 201         PerlIO_printf(g_fp,"* %"UVxf"\n", (UV)id);
 202     }
 203     else if(ptype == OP_DIE) {
 204         PerlIO_printf(g_fp,"/ %"UVxf"\n", (UV)id);
 205     }
 206     else {
 207         PerlIO_printf(g_fp,"Profiler unknown prof code %d\n", ptype);
 208     }
 209 }
 210
 211 static void
 212 prof_dumps(pTHX_ U32 id, char *pname, char *gname)
 213 {
 214     PerlIO_printf(g_fp,"& %"UVxf" %s %s\n", (UV)id, pname, gname);
 215 }
 216
 217 static void
 218 prof_dumpt(pTHX_ long tms_utime, long tms_stime, long realtime)
 219 {
 220     PerlIO_printf(g_fp,"@ %ld %ld %ld\n", tms_utime, tms_stime, realtime);
 221 }
 222
 223 static void
 224 prof_dump_until(pTHX_ long ix)
 225 {
 226     long base = 0;
 227     struct tms t1, t2;
 228     clock_t realtime1, realtime2;
 229
 230     realtime1 = Times(&t1);
 231
 232     while (base < ix) {
 233         opcode ptype = g_profstack[base++].ptype;
 234         if (ptype == OP_TIME) {
 235             long tms_utime = g_profstack[base++].tms_utime;
 236             long tms_stime = g_profstack[base++].tms_stime;
 237             long realtime = g_profstack[base++].realtime;
 238
 239             prof_dumpt(aTHX_ tms_utime, tms_stime, realtime);
 240         }
 241         else if (ptype == OP_GV) {
 242             U32 id = g_profstack[base++].id;
 243             char *pname = g_profstack[base++].name;
 244             char *gname = g_profstack[base++].name;
 245
 246             prof_dumps(aTHX_ id, pname, gname);
 247         }
 248         else {
 249             U32 id = g_profstack[base++].id;
 250             prof_dumpa(aTHX_ ptype, id);
 251         }
 252     }
 253     PerlIO_flush(g_fp);
 254     realtime2 = Times(&t2);
 255     if (realtime2 != realtime1 || t1.tms_utime != t2.tms_utime
 256         || t1.tms_stime != t2.tms_stime) {
 257         g_wprof_r += realtime2 - realtime1;
 258         g_wprof_u += t2.tms_utime - t1.tms_utime;
 259         g_wprof_s += t2.tms_stime - t1.tms_stime;
 260
 261         PerlIO_printf(g_fp,"+ & Devel::DProf::write\n");
 262         PerlIO_printf(g_fp,"@ %"IVdf" %"IVdf" %"IVdf"\n",
 263                       /* The (IV) casts are one possibility:
 264                        * the Painfully Correct Way would be to
 265                        * have Clock_t_f. */
 266                       (IV)(t2.tms_utime - t1.tms_utime),
 267                       (IV)(t2.tms_stime - t1.tms_stime),
 268                       (IV)(realtime2 - realtime1));
 269         PerlIO_printf(g_fp,"- & Devel::DProf::write\n");
 270         g_otms_utime = t2.tms_utime;
 271         g_otms_stime = t2.tms_stime;
 272         g_orealtime = realtime2;
 273         PerlIO_flush(g_fp);
 274     }
 275 }
 276
 277 static void
 278 prof_mark(pTHX_ opcode ptype)
 279 {
 280     struct tms t;
 281     clock_t realtime, rdelta, udelta, sdelta;
 282     char *name, *pv;
 283     char *hvname;
 284     STRLEN len;
 285     SV *sv;
 286     U32 id;
 287     SV *Sub = GvSV(PL_DBsub);   /* name of current sub */
 288
 289     if (g_SAVE_STACK) {
 290         if (g_profstack_ix + 5 > g_profstack_max) {
 291                 g_profstack_max = g_profstack_max * 3 / 2;
 292                 Renew(g_profstack, g_profstack_max, PROFANY);
 293         }
 294     }
 295
 296     realtime = Times(&t);
 297     rdelta = realtime - g_orealtime;
 298     udelta = t.tms_utime - g_otms_utime;
 299     sdelta = t.tms_stime - g_otms_stime;
 300     if (rdelta || udelta || sdelta) {
 301         if (g_SAVE_STACK) {
 302             g_profstack[g_profstack_ix++].ptype = OP_TIME;
 303             g_profstack[g_profstack_ix++].tms_utime = udelta;
 304             g_profstack[g_profstack_ix++].tms_stime = sdelta;
 305             g_profstack[g_profstack_ix++].realtime = rdelta;
 306         }
 307         else { /* Write it to disk now so's not to eat up core */
 308             if (g_prof_pid == (int)getpid()) {
 309                 prof_dumpt(aTHX_ udelta, sdelta, rdelta);
 310                 PerlIO_flush(g_fp);
 311             }
 312         }
 313         g_orealtime = realtime;
 314         g_otms_stime = t.tms_stime;
 315         g_otms_utime = t.tms_utime;
 316     }
 317
 318     {
 319         SV **svp;
 320         char *gname, *pname;
 321         CV *cv;
 322
 323         cv = INT2PTR(CV*,SvIVX(Sub));
 324         svp = hv_fetch(g_cv_hash, (char*)&cv, sizeof(CV*), TRUE);
 325         if (!SvOK(*svp)) {
 326             GV *gv = CvGV(cv);
 327
 328             sv_setiv(*svp, id = ++g_lastid);
 329             pname = ((GvSTASH(gv) && HvNAME(GvSTASH(gv)))
 330                      ? HvNAME(GvSTASH(gv))
 331                      : "(null)");
 332             gname = GvNAME(gv);
 333             if (CvXSUB(cv) == XS_Devel__DProf_END)
 334                 return;
 335             if (g_SAVE_STACK) { /* Store it for later recording  -JH */
 336                 g_profstack[g_profstack_ix++].ptype = OP_GV;
 337                 g_profstack[g_profstack_ix++].id = id;
 338                 g_profstack[g_profstack_ix++].name = pname;
 339                 g_profstack[g_profstack_ix++].name = gname;
 340             }
 341             else { /* Write it to disk now so's not to eat up core */
 342                 /* Only record the parent's info */
 343                 if (g_prof_pid == (int)getpid()) {
 344                     prof_dumps(aTHX_ id, pname, gname);
 345                     PerlIO_flush(g_fp);
 346                 }
 347                 else
 348                     PL_perldb = 0;              /* Do not debug the kid. */
 349             }
 350         }
 351         else {
 352             id = SvIV(*svp);
 353         }
 354     }
 355
 356     g_total++;
 357     if (g_SAVE_STACK) { /* Store it for later recording  -JH */
 358         g_profstack[g_profstack_ix++].ptype = ptype;
 359         g_profstack[g_profstack_ix++].id = id;
 360
 361         /* Only record the parent's info */
 362         if (g_SAVE_STACK < g_profstack_ix) {
 363             if (g_prof_pid == (int)getpid())
 364                 prof_dump_until(aTHX_ g_profstack_ix);
 365             else
 366                 PL_perldb = 0;          /* Do not debug the kid. */
 367             g_profstack_ix = 0;
 368         }
 369     }
 370     else { /* Write it to disk now so's not to eat up core */
 371
 372         /* Only record the parent's info */
 373         if (g_prof_pid == (int)getpid()) {
 374             prof_dumpa(aTHX_ ptype, id);
 375             PerlIO_flush(g_fp);
 376         }
 377         else
 378             PL_perldb = 0;              /* Do not debug the kid. */
 379     }
 380 }
 381
 382 #ifdef PL_NEEDED
 383 #  define defstash PL_defstash
 384 #endif
 385
 386 /* Counts overhead of prof_mark and extra XS call. */
 387 static void
 388 test_time(pTHX_ clock_t *r, clock_t *u, clock_t *s)
 389 {
 390     dTHR;
 391     CV *cv = perl_get_cv("Devel::DProf::NONESUCH_noxs", FALSE);
 392     int i, j, k = 0;
 393     HV *oldstash = PL_curstash;
 394     struct tms t1, t2;
 395     clock_t realtime1, realtime2;
 396     U32 ototal = g_total;
 397     U32 ostack = g_SAVE_STACK;
 398     U32 operldb = PL_perldb;
 399
 400     g_SAVE_STACK = 1000000;
 401     realtime1 = Times(&t1);
 402
 403     while (k < 2) {
 404         i = 0;
 405             /* Disable debugging of perl_call_sv on second pass: */
 406         PL_curstash = (k == 0 ? PL_defstash : PL_debstash);
 407         PL_perldb = g_default_perldb;
 408         while (++i <= 100) {
 409             j = 0;
 410             g_profstack_ix = 0;         /* Do not let the stack grow */
 411             while (++j <= 100) {
 412 /*              prof_mark(aTHX_ OP_ENTERSUB); */
 413
 414                 PUSHMARK(PL_stack_sp);
 415                 perl_call_sv((SV*)cv, G_SCALAR);
 416                 PL_stack_sp--;
 417 /*              prof_mark(aTHX_ OP_LEAVESUB); */
 418             }
 419         }
 420         PL_curstash = oldstash;
 421         if (k == 0) {                   /* Put time with debugging */
 422             realtime2 = Times(&t2);
 423             *r = realtime2 - realtime1;
 424             *u = t2.tms_utime - t1.tms_utime;
 425             *s = t2.tms_stime - t1.tms_stime;
 426         }
 427         else {                          /* Subtract time without debug */
 428             realtime1 = Times(&t1);
 429             *r -= realtime1 - realtime2;
 430             *u -= t1.tms_utime - t2.tms_utime;
 431             *s -= t1.tms_stime - t2.tms_stime;
 432         }
 433         k++;
 434     }
 435     g_total = ototal;
 436     g_SAVE_STACK = ostack;
 437     PL_perldb = operldb;
 438 }
 439
 440 static void
 441 prof_recordheader(pTHX)
 442 {
 443     clock_t r, u, s;
 444
 445     /* g_fp is opened in the BOOT section */
 446     PerlIO_printf(g_fp, "#fOrTyTwO\n");
 447     PerlIO_printf(g_fp, "$hz=%"IVdf";\n", (IV)DPROF_HZ);
 448     PerlIO_printf(g_fp, "$XS_VERSION='DProf %s';\n", XS_VERSION);
 449     PerlIO_printf(g_fp, "# All values are given in HZ\n");
 450     test_time(aTHX_ &r, &u, &s);
 451     PerlIO_printf(g_fp,
 452                   "$over_utime=%"IVdf"; $over_stime=%"IVdf"; $over_rtime=%"IVdf";\n",
 453                   /* The (IV) casts are one possibility:
 454                    * the Painfully Correct Way would be to
 455                    * have Clock_t_f. */
 456                   (IV)u, (IV)s, (IV)r);
 457     PerlIO_printf(g_fp, "$over_tests=10000;\n");
 458
 459     g_TIMES_LOCATION = PerlIO_tell(g_fp);
 460
 461     /* Pad with whitespace. */
 462     /* This should be enough even for very large numbers. */
 463     PerlIO_printf(g_fp, "%*s\n", 240 , "");
 464
 465     PerlIO_printf(g_fp, "\n");
 466     PerlIO_printf(g_fp, "PART2\n");
 467
 468     PerlIO_flush(g_fp);
 469 }
 470
 471 static void
 472 prof_record(pTHX)
 473 {
 474     /* g_fp is opened in the BOOT section */
 475
 476     /* Now that we know the runtimes, fill them in at the recorded
 477        location -JH */
 478
 479     clock_t r, u, s;
 480
 481     if (g_SAVE_STACK) {
 482         prof_dump_until(aTHX_ g_profstack_ix);
 483     }
 484     PerlIO_seek(g_fp, g_TIMES_LOCATION, SEEK_SET);
 485     /* Write into reserved 240 bytes: */
 486     PerlIO_printf(g_fp,
 487                   "$rrun_utime=%"IVdf"; $rrun_stime=%"IVdf"; $rrun_rtime=%"IVdf";",
 488                   /* The (IV) casts are one possibility:
 489                    * the Painfully Correct Way would be to
 490                    * have Clock_t_f. */
 491                   (IV)(g_prof_end.tms_utime-g_prof_start.tms_utime-g_wprof_u),
 492                   (IV)(g_prof_end.tms_stime-g_prof_start.tms_stime-g_wprof_s),
 493                   (IV)(g_rprof_end-g_rprof_start-g_wprof_r));
 494     PerlIO_printf(g_fp, "\n$total_marks=%"IVdf, (IV)g_total);
 495
 496     PerlIO_close(g_fp);
 497 }
 498
 499 #define NONESUCH()
 500
 501 static void
 502 check_depth(pTHX_ void *foo)
 503 {
 504     U32 need_depth = (U32)foo;
 505     if (need_depth != g_depth) {
 506         if (need_depth > g_depth) {
 507             warn("garbled call depth when profiling");
 508         }
 509         else {
 510             I32 marks = g_depth - need_depth;
 511
 512 /*          warn("Check_depth: got %d, expected %d\n", g_depth, need_depth); */
 513             while (marks--) {
 514                 prof_mark(aTHX_ OP_DIE);
 515             }
 516             g_depth = need_depth;
 517         }
 518     }
 519 }
 520
 521 #define for_real
 522 #ifdef for_real
 523
 524 XS(XS_DB_sub)
 525 {
 526     dXSARGS;
 527     dORIGMARK;
 528     SV *Sub = GvSV(PL_DBsub);           /* name of current sub */
 529
 530 #ifdef PERL_IMPLICIT_CONTEXT
 531     /* profile only the interpreter that loaded us */
 532     if (g_THX != aTHX) {
 533         PUSHMARK(ORIGMARK);
 534         perl_call_sv(INT2PTR(SV*,SvIV(Sub)), GIMME | G_NODEBUG);
 535     }
 536     else
 537 #endif
 538     {
 539         HV *oldstash = PL_curstash;
 540
 541         DBG_SUB_NOTIFY("XS DBsub(%s)\n", SvPV(Sub, na));
 542
 543         SAVEDESTRUCTOR_X(check_depth, (void*)g_depth);
 544         g_depth++;
 545
 546         prof_mark(aTHX_ OP_ENTERSUB);
 547         PUSHMARK(ORIGMARK);
 548         perl_call_sv(INT2PTR(SV*,SvIV(Sub)), GIMME | G_NODEBUG);
 549         prof_mark(aTHX_ OP_LEAVESUB);
 550         g_depth--;
 551     }
 552     return;
 553 }
 554
 555 XS(XS_DB_goto)
 556 {
 557 #ifdef PERL_IMPLICIT_CONTEXT
 558     if (g_THX == aTHX)
 559 #endif
 560     {
 561         prof_mark(aTHX_ OP_GOTO);
 562         return;
 563     }
 564 }
 565
 566 #endif /* for_real */
 567
 568 #ifdef testing
 569
 570         MODULE = Devel::DProf           PACKAGE = DB
 571
 572         void
 573         sub(...)
 574         PPCODE:
 575             {
 576                 dORIGMARK;
 577                 HV *oldstash = PL_curstash;
 578                 SV *Sub = GvSV(PL_DBsub);       /* name of current sub */
 579                 /* SP -= items;  added by xsubpp */
 580                 DBG_SUB_NOTIFY("XS DBsub(%s)\n", SvPV(Sub, na));
 581
 582                 sv_setiv(PL_DBsingle, 0);       /* disable DB single-stepping */
 583
 584                 prof_mark(aTHX_ OP_ENTERSUB);
 585                 PUSHMARK(ORIGMARK);
 586
 587                 PL_curstash = PL_debstash;      /* To disable debugging of perl_call_sv */
 588                 perl_call_sv(Sub, GIMME);
 589                 PL_curstash = oldstash;
 590
 591                 prof_mark(aTHX_ OP_LEAVESUB);
 592                 SPAGAIN;
 593                 /* PUTBACK;  added by xsubpp */
 594             }
 595
 596 #endif /* testing */
 597
 598 MODULE = Devel::DProf           PACKAGE = Devel::DProf
 599
 600 void
 601 END()
 602 PPCODE:
 603     {
 604         if (PL_DBsub) {
 605             /* maybe the process forked--we want only
 606              * the parent's profile.
 607              */
 608             if (
 609 #ifdef PERL_IMPLICIT_CONTEXT
 610                 g_THX == aTHX &&
 611 #endif
 612                 g_prof_pid == (int)getpid())
 613             {
 614                 g_rprof_end = Times(&g_prof_end);
 615                 DBG_TIMER_NOTIFY("Profiler timer is off.\n");
 616                 prof_record(aTHX);
 617             }
 618         }
 619     }
 620
 621 void
 622 NONESUCH()
 623
 624 BOOT:
 625     {
 626         g_TIMES_LOCATION = 42;
 627         g_SAVE_STACK = 1<<14;
 628         g_profstack_max = 128;
 629 #ifdef PERL_IMPLICIT_CONTEXT
 630         g_THX = aTHX;
 631 #endif
 632
 633         /* Before we go anywhere make sure we were invoked
 634          * properly, else we'll dump core.
 635          */
 636         if (!PL_DBsub)
 637             croak("DProf: run perl with -d to use DProf.\n");
 638
 639         /* When we hook up the XS DB::sub we'll be redefining
 640          * the DB::sub from the PM file.  Turn off warnings
 641          * while we do this.
 642          */
 643         {
 644             I32 warn_tmp = PL_dowarn;
 645             PL_dowarn = 0;
 646             newXS("DB::sub", XS_DB_sub, file);
 647             newXS("DB::goto", XS_DB_goto, file);
 648             PL_dowarn = warn_tmp;
 649         }
 650
 651         sv_setiv(PL_DBsingle, 0);       /* disable DB single-stepping */
 652
 653         {
 654             char *buffer = getenv("PERL_DPROF_BUFFER");
 655
 656             if (buffer) {
 657                 g_SAVE_STACK = atoi(buffer);
 658             }
 659
 660             buffer = getenv("PERL_DPROF_TICKS");
 661
 662             if (buffer) {
 663                 g_dprof_ticks = atoi(buffer); /* Used under OS/2 only */
 664             }
 665             else {
 666                 g_dprof_ticks = HZ;
 667             }
 668
 669             buffer = getenv("PERL_DPROF_OUT_FILE_NAME");
 670             g_out_file_name = savepv(buffer ? buffer : "tmon.out");
 671         }
 672
 673         if ((g_fp = PerlIO_open(g_out_file_name, "w")) == NULL)
 674             croak("DProf: unable to write '%s', errno = %d\n",
 675                   g_out_file_name, errno);
 676
 677         g_default_perldb = PERLDBf_NONAME | PERLDBf_SUB | PERLDBf_GOTO;
 678         g_cv_hash = newHV();
 679         g_prof_pid = (int)getpid();
 680
 681         New(0, g_profstack, g_profstack_max, PROFANY);
 682         prof_recordheader(aTHX);
 683         DBG_TIMER_NOTIFY("Profiler timer is on.\n");
 684         g_orealtime = g_rprof_start = Times(&g_prof_start);
 685         g_otms_utime = g_prof_start.tms_utime;
 686         g_otms_stime = g_prof_start.tms_stime;
 687         PL_perldb = g_default_perldb;
 688     }