xref: /freebsd/usr.bin/gprof/gprof.c (revision cab6a39d7b343596a5823e65c0f7b426551ec22d)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 static const char copyright[] =
34 "@(#) Copyright (c) 1983, 1993\n\
35 	The Regents of the University of California.  All rights reserved.\n";
36 #endif /* not lint */
37 
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)gprof.c	8.1 (Berkeley) 6/6/93";
41 #endif /* not lint */
42 #endif
43 
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 #include <err.h>
48 #include <limits.h>
49 #include <stdint.h>
50 #include <string.h>
51 
52 #define	EXTERN
53 #include "gprof.h"
54 
55 static int valcmp(const void *, const void *);
56 
57 static struct gmonhdr	gmonhdr;
58 static int lflag;
59 static int Lflag;
60 
61 int
62 main(int argc, char **argv)
63 {
64     char	**sp;
65     nltype	**timesortnlp;
66     char	**defaultEs;
67 
68     --argc;
69     argv++;
70     debug = 0;
71     bflag = TRUE;
72     while ( *argv != 0 && **argv == '-' ) {
73 	(*argv)++;
74 	switch ( **argv ) {
75 	case 'a':
76 	    aflag = TRUE;
77 	    break;
78 	case 'b':
79 	    bflag = FALSE;
80 	    break;
81 	case 'C':
82 	    Cflag = TRUE;
83 	    cyclethreshold = atoi( *++argv );
84 	    break;
85 	case 'd':
86 	    dflag = TRUE;
87 	    setlinebuf(stdout);
88 	    debug |= atoi( *++argv );
89 	    debug |= ANYDEBUG;
90 #	    ifdef DEBUG
91 		printf("[main] debug = %d\n", debug);
92 #	    else /* not DEBUG */
93 		printf("gprof: -d ignored\n");
94 #	    endif /* DEBUG */
95 	    break;
96 	case 'E':
97 	    ++argv;
98 	    addlist( Elist , *argv );
99 	    Eflag = TRUE;
100 	    addlist( elist , *argv );
101 	    eflag = TRUE;
102 	    break;
103 	case 'e':
104 	    addlist( elist , *++argv );
105 	    eflag = TRUE;
106 	    break;
107 	case 'F':
108 	    ++argv;
109 	    addlist( Flist , *argv );
110 	    Fflag = TRUE;
111 	    addlist( flist , *argv );
112 	    fflag = TRUE;
113 	    break;
114 	case 'f':
115 	    addlist( flist , *++argv );
116 	    fflag = TRUE;
117 	    break;
118 	case 'k':
119 	    addlist( kfromlist , *++argv );
120 	    addlist( ktolist , *++argv );
121 	    kflag = TRUE;
122 	    break;
123 	case 'K':
124 	    Kflag = TRUE;
125 	    break;
126 	case 'l':
127 	    lflag = 1;
128 	    Lflag = 0;
129 	    break;
130 	case 'L':
131 	    Lflag = 1;
132 	    lflag = 0;
133 	    break;
134 	case 's':
135 	    sflag = TRUE;
136 	    break;
137 	case 'u':
138 	    uflag = TRUE;
139 	    break;
140 	case 'z':
141 	    zflag = TRUE;
142 	    break;
143 	}
144 	argv++;
145     }
146     if ( *argv != 0 ) {
147 	a_outname  = *argv;
148 	argv++;
149     } else {
150 	a_outname  = A_OUTNAME;
151     }
152     if ( *argv != 0 ) {
153 	gmonname = *argv;
154 	argv++;
155     } else {
156 	gmonname = (char *) malloc(strlen(a_outname)+6);
157 	strcpy(gmonname, a_outname);
158 	strcat(gmonname, ".gmon");
159     }
160 	/*
161 	 *	get information from the executable file.
162 	 */
163     if ((Kflag && kernel_getnfile(a_outname, &defaultEs) == -1) ||
164       (!Kflag && elf_getnfile(a_outname, &defaultEs) == -1))
165 	errx(1, "%s: bad format", a_outname);
166 	/*
167 	 *	sort symbol table.
168 	 */
169     qsort(nl, nname, sizeof(nltype), valcmp);
170 	/*
171 	 *	turn off default functions
172 	 */
173     for ( sp = defaultEs ; *sp ; sp++ ) {
174 	Eflag = TRUE;
175 	addlist( Elist , *sp );
176 	eflag = TRUE;
177 	addlist( elist , *sp );
178     }
179 	/*
180 	 *	get information about mon.out file(s).
181 	 */
182     do	{
183 	getpfile( gmonname );
184 	if ( *argv != 0 ) {
185 	    gmonname = *argv;
186 	}
187     } while ( *argv++ != 0 );
188 	/*
189 	 *	how many ticks per second?
190 	 *	if we can't tell, report time in ticks.
191 	 */
192     if (hz == 0) {
193 	hz = 1;
194 	fprintf(stderr, "time is in ticks, not seconds\n");
195     }
196 	/*
197 	 *	dump out a gmon.sum file if requested
198 	 */
199     if ( sflag ) {
200 	dumpsum( GMONSUM );
201     }
202 	/*
203 	 *	assign samples to procedures
204 	 */
205     asgnsamples();
206 	/*
207 	 *	assemble the dynamic profile
208 	 */
209     timesortnlp = doarcs();
210 	/*
211 	 *	print the dynamic profile
212 	 */
213     if(!lflag) {
214 	    printgprof( timesortnlp );
215     }
216 	/*
217 	 *	print the flat profile
218 	 */
219     if(!Lflag) {
220 	    printprof();
221     }
222 	/*
223 	 *	print the index
224 	 */
225     printindex();
226     exit(0);
227 }
228 
229     /*
230      *	information from a gmon.out file is in two parts:
231      *	an array of sampling hits within pc ranges,
232      *	and the arcs.
233      */
234 void
235 getpfile(char *filename)
236 {
237     FILE		*pfile;
238     struct rawarc	arc;
239 
240     pfile = openpfile(filename);
241     readsamples(pfile);
242 	/*
243 	 *	the rest of the file consists of
244 	 *	a bunch of <from,self,count> tuples.
245 	 */
246     while ( fread( &arc , sizeof arc , 1 , pfile ) == 1 ) {
247 #	ifdef DEBUG
248 	    if ( debug & SAMPLEDEBUG ) {
249 		printf( "[getpfile] frompc 0x%lx selfpc 0x%lx count %ld\n" ,
250 			arc.raw_frompc , arc.raw_selfpc , arc.raw_count );
251 	    }
252 #	endif /* DEBUG */
253 	    /*
254 	     *	add this arc
255 	     */
256 	tally( &arc );
257     }
258     fclose(pfile);
259 }
260 
261 FILE *
262 openpfile(char *filename)
263 {
264     struct gmonhdr	tmp;
265     FILE		*pfile;
266     int			size;
267     int			rate;
268 
269     if((pfile = fopen(filename, "r")) == NULL)
270 	err(1, "%s", filename);
271     fread(&tmp, sizeof(struct gmonhdr), 1, pfile);
272     if ( s_highpc != 0 && ( tmp.lpc != gmonhdr.lpc ||
273 	 tmp.hpc != gmonhdr.hpc || tmp.ncnt != gmonhdr.ncnt ) )
274 	errx(1, "%s: incompatible with first gmon file", filename);
275     gmonhdr = tmp;
276     if ( gmonhdr.version == GMONVERSION ) {
277 	rate = gmonhdr.profrate;
278 	size = sizeof(struct gmonhdr);
279     } else {
280 	fseek(pfile, sizeof(struct ophdr), SEEK_SET);
281 	size = sizeof(struct ophdr);
282 	gmonhdr.profrate = rate = hertz();
283 	gmonhdr.version = GMONVERSION;
284     }
285     if (hz == 0) {
286 	hz = rate;
287     } else if (hz != rate)
288 	errx(0, "%s: profile clock rate (%d) %s (%ld) in first gmon file",
289 	    filename, rate, "incompatible with clock rate", hz);
290     if ( gmonhdr.histcounter_type == 0 ) {
291 	/* Historical case.  The type was u_short (2 bytes in practice). */
292 	histcounter_type = 16;
293 	histcounter_size = 2;
294     } else {
295 	histcounter_type = gmonhdr.histcounter_type;
296 	histcounter_size = abs(histcounter_type) / CHAR_BIT;
297     }
298     s_lowpc = (unsigned long) gmonhdr.lpc;
299     s_highpc = (unsigned long) gmonhdr.hpc;
300     lowpc = (unsigned long)gmonhdr.lpc / HISTORICAL_SCALE_2;
301     highpc = (unsigned long)gmonhdr.hpc / HISTORICAL_SCALE_2;
302     sampbytes = gmonhdr.ncnt - size;
303     nsamples = sampbytes / histcounter_size;
304 #   ifdef DEBUG
305 	if ( debug & SAMPLEDEBUG ) {
306 	    printf( "[openpfile] hdr.lpc 0x%lx hdr.hpc 0x%lx hdr.ncnt %d\n",
307 		gmonhdr.lpc , gmonhdr.hpc , gmonhdr.ncnt );
308 	    printf( "[openpfile]   s_lowpc 0x%lx   s_highpc 0x%lx\n" ,
309 		s_lowpc , s_highpc );
310 	    printf( "[openpfile]     lowpc 0x%lx     highpc 0x%lx\n" ,
311 		lowpc , highpc );
312 	    printf( "[openpfile] sampbytes %d nsamples %d\n" ,
313 		sampbytes , nsamples );
314 	    printf( "[openpfile] sample rate %ld\n" , hz );
315 	}
316 #   endif /* DEBUG */
317     return(pfile);
318 }
319 
320 void
321 tally(struct rawarc *rawp)
322 {
323     nltype		*parentp;
324     nltype		*childp;
325 
326     parentp = nllookup( rawp -> raw_frompc );
327     childp = nllookup( rawp -> raw_selfpc );
328     if ( parentp == 0 || childp == 0 )
329 	return;
330     if ( kflag
331 	 && onlist( kfromlist , parentp -> name )
332 	 && onlist( ktolist , childp -> name ) ) {
333 	return;
334     }
335     childp -> ncall += rawp -> raw_count;
336 #   ifdef DEBUG
337 	if ( debug & TALLYDEBUG ) {
338 	    printf( "[tally] arc from %s to %s traversed %ld times\n" ,
339 		    parentp -> name , childp -> name , rawp -> raw_count );
340 	}
341 #   endif /* DEBUG */
342     addarc( parentp , childp , rawp -> raw_count );
343 }
344 
345 /*
346  * dump out the gmon.sum file
347  */
348 void
349 dumpsum(const char *sumfile)
350 {
351     register nltype *nlp;
352     register arctype *arcp;
353     struct rawarc arc;
354     FILE *sfile;
355 
356     if ( ( sfile = fopen ( sumfile , "w" ) ) == NULL )
357 	err( 1 , "%s" , sumfile );
358     /*
359      * dump the header; use the last header read in
360      */
361     if ( fwrite( &gmonhdr , sizeof gmonhdr , 1 , sfile ) != 1 )
362 	err( 1 , "%s" , sumfile );
363     /*
364      * dump the samples
365      */
366     if (fwrite(samples, histcounter_size, nsamples, sfile) != nsamples)
367 	err( 1 , "%s" , sumfile );
368     /*
369      * dump the normalized raw arc information
370      */
371     for ( nlp = nl ; nlp < npe ; nlp++ ) {
372 	for ( arcp = nlp -> children ; arcp ; arcp = arcp -> arc_childlist ) {
373 	    arc.raw_frompc = arcp -> arc_parentp -> value;
374 	    arc.raw_selfpc = arcp -> arc_childp -> value;
375 	    arc.raw_count = arcp -> arc_count;
376 	    if ( fwrite ( &arc , sizeof arc , 1 , sfile ) != 1 )
377 		err( 1 , "%s" , sumfile );
378 #	    ifdef DEBUG
379 		if ( debug & SAMPLEDEBUG ) {
380 		    printf( "[dumpsum] frompc 0x%lx selfpc 0x%lx count %ld\n" ,
381 			    arc.raw_frompc , arc.raw_selfpc , arc.raw_count );
382 		}
383 #	    endif /* DEBUG */
384 	}
385     }
386     fclose( sfile );
387 }
388 
389 static int
390 valcmp(const void *v1, const void *v2)
391 {
392     const nltype *p1 = (const nltype *)v1;
393     const nltype *p2 = (const nltype *)v2;
394 
395     if ( p1 -> value < p2 -> value ) {
396 	return LESSTHAN;
397     }
398     if ( p1 -> value > p2 -> value ) {
399 	return GREATERTHAN;
400     }
401     return EQUALTO;
402 }
403 
404 void
405 readsamples(FILE *pfile)
406 {
407     int		i;
408     intmax_t	sample;
409 
410     if (samples == 0) {
411 	samples = (double *) calloc(nsamples, sizeof(double));
412 	if (samples == NULL)
413 	    errx(0, "no room for %d sample pc's", nsamples);
414     }
415     for (i = 0; i < nsamples; i++) {
416 	fread(&sample, histcounter_size, 1, pfile);
417 	if (feof(pfile))
418 		break;
419 	switch ( histcounter_type ) {
420 	case -8:
421 	    samples[i] += *(int8_t *)&sample;
422 	    break;
423 	case 8:
424 	    samples[i] += *(u_int8_t *)&sample;
425 	    break;
426 	case -16:
427 	    samples[i] += *(int16_t *)&sample;
428 	    break;
429 	case 16:
430 	    samples[i] += *(u_int16_t *)&sample;
431 	    break;
432 	case -32:
433 	    samples[i] += *(int32_t *)&sample;
434 	    break;
435 	case 32:
436 	    samples[i] += *(u_int32_t *)&sample;
437 	    break;
438 	case -64:
439 	    samples[i] += *(int64_t *)&sample;
440 	    break;
441 	case 64:
442 	    samples[i] += *(u_int64_t *)&sample;
443 	    break;
444 	default:
445 	    err(1, "unsupported histogram counter type %d", histcounter_type);
446 	}
447     }
448     if (i != nsamples)
449 	errx(1, "unexpected EOF after reading %d/%d samples", --i , nsamples );
450 }
451 
452 /*
453  *	Assign samples to the procedures to which they belong.
454  *
455  *	There are three cases as to where pcl and pch can be
456  *	with respect to the routine entry addresses svalue0 and svalue1
457  *	as shown in the following diagram.  overlap computes the
458  *	distance between the arrows, the fraction of the sample
459  *	that is to be credited to the routine which starts at svalue0.
460  *
461  *	    svalue0                                         svalue1
462  *	       |                                               |
463  *	       v                                               v
464  *
465  *	       +-----------------------------------------------+
466  *	       |					       |
467  *	  |  ->|    |<-		->|         |<-		->|    |<-  |
468  *	  |         |		  |         |		  |         |
469  *	  +---------+		  +---------+		  +---------+
470  *
471  *	  ^         ^		  ^         ^		  ^         ^
472  *	  |         |		  |         |		  |         |
473  *	 pcl       pch		 pcl       pch		 pcl       pch
474  *
475  *	For the vax we assert that samples will never fall in the first
476  *	two bytes of any routine, since that is the entry mask,
477  *	thus we give call alignentries() to adjust the entry points if
478  *	the entry mask falls in one bucket but the code for the routine
479  *	doesn't start until the next bucket.  In conjunction with the
480  *	alignment of routine addresses, this should allow us to have
481  *	only one sample for every four bytes of text space and never
482  *	have any overlap (the two end cases, above).
483  */
484 void
485 asgnsamples(void)
486 {
487     register int	j;
488     double		ccnt;
489     double		thetime;
490     unsigned long	pcl, pch;
491     register int	i;
492     unsigned long	overlap;
493     unsigned long	svalue0, svalue1;
494 
495     /* read samples and assign to namelist symbols */
496     scale = highpc - lowpc;
497     scale /= nsamples;
498     alignentries();
499     for (i = 0, j = 1; i < nsamples; i++) {
500 	ccnt = samples[i];
501 	if (ccnt == 0)
502 		continue;
503 	pcl = lowpc + (unsigned long)(scale * i);
504 	pch = lowpc + (unsigned long)(scale * (i + 1));
505 	thetime = ccnt;
506 #	ifdef DEBUG
507 	    if ( debug & SAMPLEDEBUG ) {
508 		printf( "[asgnsamples] pcl 0x%lx pch 0x%lx ccnt %.0f\n" ,
509 			pcl , pch , ccnt );
510 	    }
511 #	endif /* DEBUG */
512 	totime += thetime;
513 	for (j = j - 1; j < nname; j++) {
514 	    svalue0 = nl[j].svalue;
515 	    svalue1 = nl[j+1].svalue;
516 		/*
517 		 *	if high end of tick is below entry address,
518 		 *	go for next tick.
519 		 */
520 	    if (pch < svalue0)
521 		    break;
522 		/*
523 		 *	if low end of tick into next routine,
524 		 *	go for next routine.
525 		 */
526 	    if (pcl >= svalue1)
527 		    continue;
528 	    overlap = min(pch, svalue1) - max(pcl, svalue0);
529 	    if (overlap > 0) {
530 #		ifdef DEBUG
531 		    if (debug & SAMPLEDEBUG) {
532 			printf("[asgnsamples] (0x%lx->0x%lx-0x%lx) %s gets %f ticks %lu overlap\n",
533 				nl[j].value / HISTORICAL_SCALE_2,
534 				svalue0, svalue1, nl[j].name,
535 				overlap * thetime / scale, overlap);
536 		    }
537 #		endif /* DEBUG */
538 		nl[j].time += overlap * thetime / scale;
539 	    }
540 	}
541     }
542 #   ifdef DEBUG
543 	if (debug & SAMPLEDEBUG) {
544 	    printf("[asgnsamples] totime %f\n", totime);
545 	}
546 #   endif /* DEBUG */
547 }
548 
549 
550 unsigned long
551 min(unsigned long a, unsigned long b)
552 {
553     if (a<b)
554 	return(a);
555     return(b);
556 }
557 
558 unsigned long
559 max(unsigned long a, unsigned long b)
560 {
561     if (a>b)
562 	return(a);
563     return(b);
564 }
565 
566     /*
567      *	calculate scaled entry point addresses (to save time in asgnsamples),
568      *	and possibly push the scaled entry points over the entry mask,
569      *	if it turns out that the entry point is in one bucket and the code
570      *	for a routine is in the next bucket.
571      */
572 void
573 alignentries(void)
574 {
575     register struct nl	*nlp;
576     unsigned long	bucket_of_entry;
577     unsigned long	bucket_of_code;
578 
579     for (nlp = nl; nlp < npe; nlp++) {
580 	nlp -> svalue = nlp -> value / HISTORICAL_SCALE_2;
581 	bucket_of_entry = (nlp->svalue - lowpc) / scale;
582 	bucket_of_code = (nlp->svalue + OFFSET_OF_CODE / HISTORICAL_SCALE_2 -
583 	  lowpc) / scale;
584 	if (bucket_of_entry < bucket_of_code) {
585 #	    ifdef DEBUG
586 		if (debug & SAMPLEDEBUG) {
587 		    printf("[alignentries] pushing svalue 0x%lx to 0x%lx\n",
588 			    nlp->svalue,
589 			    nlp->svalue + OFFSET_OF_CODE / HISTORICAL_SCALE_2);
590 		}
591 #	    endif /* DEBUG */
592 	    nlp->svalue += OFFSET_OF_CODE / HISTORICAL_SCALE_2;
593 	}
594     }
595 }
596