gmon.c revision 1.5
1/*	$NetBSD: gmon.c,v 1.5 1995/11/21 22:23:47 jtc Exp $	*/
2
3/*-
4 * Copyright (c) 1983, 1992, 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. All advertising materials mentioning features or use of this software
16 *    must display the following acknowledgement:
17 *	This product includes software developed by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36#if !defined(lint) && defined(LIBC_SCCS)
37#if 0
38static char sccsid[] = "@(#)gmon.c	8.1 (Berkeley) 6/4/93";
39#else
40static char rcsid[] = "$NetBSD: gmon.c,v 1.5 1995/11/21 22:23:47 jtc Exp $";
41#endif
42#endif
43
44#include <sys/param.h>
45#include <sys/time.h>
46#include <sys/gmon.h>
47#include <sys/sysctl.h>
48
49#include <stdio.h>
50#include <stdlib.h>
51#include <fcntl.h>
52#include <limits.h>
53#include <unistd.h>
54
55extern char *minbrk asm ("minbrk");
56
57struct gmonparam _gmonparam = { GMON_PROF_OFF };
58
59static int	s_scale;
60/* see profil(2) where this is describe (incorrectly) */
61#define		SCALE_1_TO_1	0x10000L
62
63#define ERR(s) write(2, s, sizeof(s))
64
65void	moncontrol __P((int));
66static int hertz __P((void));
67
68void
69monstartup(lowpc, highpc)
70	u_long lowpc;
71	u_long highpc;
72{
73	register int o;
74	char *cp;
75	struct gmonparam *p = &_gmonparam;
76
77	/*
78	 * round lowpc and highpc to multiples of the density we're using
79	 * so the rest of the scaling (here and in gprof) stays in ints.
80	 */
81	p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
82	p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
83	p->textsize = p->highpc - p->lowpc;
84	p->kcountsize = p->textsize / HISTFRACTION;
85	p->hashfraction = HASHFRACTION;
86	p->fromssize = p->textsize / HASHFRACTION;
87	p->tolimit = p->textsize * ARCDENSITY / 100;
88	if (p->tolimit < MINARCS)
89		p->tolimit = MINARCS;
90	else if (p->tolimit > MAXARCS)
91		p->tolimit = MAXARCS;
92	p->tossize = p->tolimit * sizeof(struct tostruct);
93
94	cp = sbrk(p->kcountsize + p->fromssize + p->tossize);
95	if (cp == (char *)-1) {
96		ERR("monstartup: out of memory\n");
97		return;
98	}
99#ifdef notdef
100	bzero(cp, p->kcountsize + p->fromssize + p->tossize);
101#endif
102	p->tos = (struct tostruct *)cp;
103	cp += p->tossize;
104	p->kcount = (u_short *)cp;
105	cp += p->kcountsize;
106	p->froms = (u_short *)cp;
107
108	minbrk = sbrk(0);
109	p->tos[0].link = 0;
110
111	o = p->highpc - p->lowpc;
112	if (p->kcountsize < o) {
113#ifndef notdef
114		s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
115#else /* avoid floating point */
116		int quot = o / p->kcountsize;
117
118		if (quot >= 0x10000)
119			s_scale = 1;
120		else if (quot >= 0x100)
121			s_scale = 0x10000 / quot;
122		else if (o >= 0x800000)
123			s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
124		else
125			s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
126#endif
127	} else
128		s_scale = SCALE_1_TO_1;
129
130	moncontrol(1);
131}
132
133void
134_mcleanup()
135{
136	int fd;
137	int fromindex;
138	int endfrom;
139	u_long frompc;
140	int toindex;
141	struct rawarc rawarc;
142	struct gmonparam *p = &_gmonparam;
143	struct gmonhdr gmonhdr, *hdr;
144	struct clockinfo clockinfo;
145	int mib[2];
146	size_t size;
147	char *profdir;
148	char *proffile;
149	char  buf[PATH_MAX];
150#ifdef DEBUG
151	int log, len;
152	char buf[200];
153#endif
154
155	if (p->state == GMON_PROF_ERROR)
156		ERR("_mcleanup: tos overflow\n");
157
158	size = sizeof(clockinfo);
159	mib[0] = CTL_KERN;
160	mib[1] = KERN_CLOCKRATE;
161	if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) {
162		/*
163		 * Best guess
164		 */
165		clockinfo.profhz = hertz();
166	} else if (clockinfo.profhz == 0) {
167		if (clockinfo.hz != 0)
168			clockinfo.profhz = clockinfo.hz;
169		else
170			clockinfo.profhz = hertz();
171	}
172
173	moncontrol(0);
174
175	if ((profdir = getenv("PROFDIR")) != NULL) {
176		extern char *__progname;
177		char *s, *t;
178		pid_t pid;
179		long divisor;
180
181		/* If PROFDIR contains a null value, no profiling
182		   output is produced */
183		if (*profdir == '\0') {
184			return;
185		}
186
187		t = buf;
188		s = profdir;
189		while((*t = *s) != '\0') {
190			t++;
191			s++;
192		}
193		*t++ = '/';
194
195		/*
196		 * Copy and convert pid from a pid_t to a string.  For
197		 * best performance, divisor should be initialized to
198		 * the largest power of 10 less than PID_MAX.
199		 */
200		pid = getpid();
201		divisor=10000;
202		while (divisor > pid) divisor /= 10;	/* skip leading zeros */
203		do {
204			*t++ = (pid/divisor) + '0';
205			pid %= divisor;
206		} while (divisor /= 10);
207		*t++ = '.';
208
209		s = __progname;
210		while ((*t++ = *s++) != '\0')
211			;
212
213		proffile = buf;
214	} else {
215		proffile = "gmon.out";
216	}
217
218	fd = open(proffile , O_CREAT|O_TRUNC|O_WRONLY, 0666);
219	if (fd < 0) {
220		perror( proffile );
221		return;
222	}
223#ifdef DEBUG
224	log = open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY, 0664);
225	if (log < 0) {
226		perror("mcount: gmon.log");
227		return;
228	}
229	len = sprintf(buf, "[mcleanup1] kcount 0x%x ssiz %d\n",
230	    p->kcount, p->kcountsize);
231	write(log, buf, len);
232#endif
233	hdr = (struct gmonhdr *)&gmonhdr;
234	hdr->lpc = p->lowpc;
235	hdr->hpc = p->highpc;
236	hdr->ncnt = p->kcountsize + sizeof(gmonhdr);
237	hdr->version = GMONVERSION;
238	hdr->profrate = clockinfo.profhz;
239	write(fd, (char *)hdr, sizeof *hdr);
240	write(fd, p->kcount, p->kcountsize);
241	endfrom = p->fromssize / sizeof(*p->froms);
242	for (fromindex = 0; fromindex < endfrom; fromindex++) {
243		if (p->froms[fromindex] == 0)
244			continue;
245
246		frompc = p->lowpc;
247		frompc += fromindex * p->hashfraction * sizeof(*p->froms);
248		for (toindex = p->froms[fromindex]; toindex != 0;
249		     toindex = p->tos[toindex].link) {
250#ifdef DEBUG
251			len = sprintf(buf,
252			"[mcleanup2] frompc 0x%x selfpc 0x%x count %d\n" ,
253				frompc, p->tos[toindex].selfpc,
254				p->tos[toindex].count);
255			write(log, buf, len);
256#endif
257			rawarc.raw_frompc = frompc;
258			rawarc.raw_selfpc = p->tos[toindex].selfpc;
259			rawarc.raw_count = p->tos[toindex].count;
260			write(fd, &rawarc, sizeof rawarc);
261		}
262	}
263	close(fd);
264}
265
266/*
267 * Control profiling
268 *	profiling is what mcount checks to see if
269 *	all the data structures are ready.
270 */
271void
272moncontrol(mode)
273	int mode;
274{
275	struct gmonparam *p = &_gmonparam;
276
277	if (mode) {
278		/* start */
279		profil((char *)p->kcount, p->kcountsize, p->lowpc,
280		    s_scale);
281		p->state = GMON_PROF_ON;
282	} else {
283		/* stop */
284		profil((char *)0, 0, 0, 0);
285		p->state = GMON_PROF_OFF;
286	}
287}
288
289/*
290 * discover the tick frequency of the machine
291 * if something goes wrong, we return 0, an impossible hertz.
292 */
293static int
294hertz()
295{
296	struct itimerval tim;
297
298	tim.it_interval.tv_sec = 0;
299	tim.it_interval.tv_usec = 1;
300	tim.it_value.tv_sec = 0;
301	tim.it_value.tv_usec = 0;
302	setitimer(ITIMER_REAL, &tim, 0);
303	setitimer(ITIMER_REAL, 0, &tim);
304	if (tim.it_interval.tv_usec < 2)
305		return(0);
306	return (1000000 / tim.it_interval.tv_usec);
307}
308
309
310