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gmon.c revision 1.1
      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 
     34 #if !defined(lint) && defined(LIBC_SCCS)
     35 static char sccsid[] = "@(#)gmon.c	8.1 (Berkeley) 6/4/93";
     36 #endif
     37 
     38 #include <sys/param.h>
     39 #include <sys/time.h>
     40 #include <sys/gmon.h>
     41 #include <sys/sysctl.h>
     42 
     43 #include <stdio.h>
     44 #include <fcntl.h>
     45 #include <unistd.h>
     46 
     47 extern char *minbrk asm ("minbrk");
     48 
     49 struct gmonparam _gmonparam = { GMON_PROF_OFF };
     50 
     51 static int	s_scale;
     52 /* see profil(2) where this is describe (incorrectly) */
     53 #define		SCALE_1_TO_1	0x10000L
     54 
     55 #define ERR(s) write(2, s, sizeof(s))
     56 
     57 void	moncontrol __P((int));
     58 static int hertz __P((void));
     59 
     60 void
     61 monstartup(lowpc, highpc)
     62 	u_long lowpc;
     63 	u_long highpc;
     64 {
     65 	register int o;
     66 	char *cp;
     67 	struct gmonparam *p = &_gmonparam;
     68 
     69 	/*
     70 	 * round lowpc and highpc to multiples of the density we're using
     71 	 * so the rest of the scaling (here and in gprof) stays in ints.
     72 	 */
     73 	p->lowpc = ROUNDDOWN(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
     74 	p->highpc = ROUNDUP(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
     75 	p->textsize = p->highpc - p->lowpc;
     76 	p->kcountsize = p->textsize / HISTFRACTION;
     77 	p->hashfraction = HASHFRACTION;
     78 	p->fromssize = p->textsize / HASHFRACTION;
     79 	p->tolimit = p->textsize * ARCDENSITY / 100;
     80 	if (p->tolimit < MINARCS)
     81 		p->tolimit = MINARCS;
     82 	else if (p->tolimit > MAXARCS)
     83 		p->tolimit = MAXARCS;
     84 	p->tossize = p->tolimit * sizeof(struct tostruct);
     85 
     86 	cp = sbrk(p->kcountsize + p->fromssize + p->tossize);
     87 	if (cp == (char *)-1) {
     88 		ERR("monstartup: out of memory\n");
     89 		return;
     90 	}
     91 #ifdef notdef
     92 	bzero(cp, p->kcountsize + p->fromssize + p->tossize);
     93 #endif
     94 	p->tos = (struct tostruct *)cp;
     95 	cp += p->tossize;
     96 	p->kcount = (u_short *)cp;
     97 	cp += p->kcountsize;
     98 	p->froms = (u_short *)cp;
     99 
    100 	minbrk = sbrk(0);
    101 	p->tos[0].link = 0;
    102 
    103 	o = p->highpc - p->lowpc;
    104 	if (p->kcountsize < o) {
    105 #ifndef hp300
    106 		s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
    107 #else /* avoid floating point */
    108 		int quot = o / p->kcountsize;
    109 
    110 		if (quot >= 0x10000)
    111 			s_scale = 1;
    112 		else if (quot >= 0x100)
    113 			s_scale = 0x10000 / quot;
    114 		else if (o >= 0x800000)
    115 			s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
    116 		else
    117 			s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
    118 #endif
    119 	} else
    120 		s_scale = SCALE_1_TO_1;
    121 
    122 	moncontrol(1);
    123 }
    124 
    125 void
    126 _mcleanup()
    127 {
    128 	int fd;
    129 	int fromindex;
    130 	int endfrom;
    131 	u_long frompc;
    132 	int toindex;
    133 	struct rawarc rawarc;
    134 	struct gmonparam *p = &_gmonparam;
    135 	struct gmonhdr gmonhdr, *hdr;
    136 	struct clockinfo clockinfo;
    137 	int mib[2];
    138 	size_t size;
    139 #ifdef DEBUG
    140 	int log, len;
    141 	char buf[200];
    142 #endif
    143 
    144 	if (p->state == GMON_PROF_ERROR)
    145 		ERR("_mcleanup: tos overflow\n");
    146 
    147 	size = sizeof(clockinfo);
    148 	mib[0] = CTL_KERN;
    149 	mib[1] = KERN_CLOCKRATE;
    150 	if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) {
    151 		/*
    152 		 * Best guess
    153 		 */
    154 		clockinfo.profhz = hertz();
    155 	} else if (clockinfo.profhz == 0) {
    156 		if (clockinfo.hz != 0)
    157 			clockinfo.profhz = clockinfo.hz;
    158 		else
    159 			clockinfo.profhz = hertz();
    160 	}
    161 
    162 	moncontrol(0);
    163 	fd = open("gmon.out", O_CREAT|O_TRUNC|O_WRONLY, 0666);
    164 	if (fd < 0) {
    165 		perror("mcount: gmon.out");
    166 		return;
    167 	}
    168 #ifdef DEBUG
    169 	log = open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY, 0664);
    170 	if (log < 0) {
    171 		perror("mcount: gmon.log");
    172 		return;
    173 	}
    174 	len = sprintf(buf, "[mcleanup1] kcount 0x%x ssiz %d\n",
    175 	    p->kcount, p->kcountsize);
    176 	write(log, buf, len);
    177 #endif
    178 	hdr = (struct gmonhdr *)&gmonhdr;
    179 	hdr->lpc = p->lowpc;
    180 	hdr->hpc = p->highpc;
    181 	hdr->ncnt = p->kcountsize + sizeof(gmonhdr);
    182 	hdr->version = GMONVERSION;
    183 	hdr->profrate = clockinfo.profhz;
    184 	write(fd, (char *)hdr, sizeof *hdr);
    185 	write(fd, p->kcount, p->kcountsize);
    186 	endfrom = p->fromssize / sizeof(*p->froms);
    187 	for (fromindex = 0; fromindex < endfrom; fromindex++) {
    188 		if (p->froms[fromindex] == 0)
    189 			continue;
    190 
    191 		frompc = p->lowpc;
    192 		frompc += fromindex * p->hashfraction * sizeof(*p->froms);
    193 		for (toindex = p->froms[fromindex]; toindex != 0;
    194 		     toindex = p->tos[toindex].link) {
    195 #ifdef DEBUG
    196 			len = sprintf(buf,
    197 			"[mcleanup2] frompc 0x%x selfpc 0x%x count %d\n" ,
    198 				frompc, p->tos[toindex].selfpc,
    199 				p->tos[toindex].count);
    200 			write(log, buf, len);
    201 #endif
    202 			rawarc.raw_frompc = frompc;
    203 			rawarc.raw_selfpc = p->tos[toindex].selfpc;
    204 			rawarc.raw_count = p->tos[toindex].count;
    205 			write(fd, &rawarc, sizeof rawarc);
    206 		}
    207 	}
    208 	close(fd);
    209 }
    210 
    211 /*
    212  * Control profiling
    213  *	profiling is what mcount checks to see if
    214  *	all the data structures are ready.
    215  */
    216 void
    217 moncontrol(mode)
    218 	int mode;
    219 {
    220 	struct gmonparam *p = &_gmonparam;
    221 
    222 	if (mode) {
    223 		/* start */
    224 		profil((char *)p->kcount, p->kcountsize, (int)p->lowpc,
    225 		    s_scale);
    226 		p->state = GMON_PROF_ON;
    227 	} else {
    228 		/* stop */
    229 		profil((char *)0, 0, 0, 0);
    230 		p->state = GMON_PROF_OFF;
    231 	}
    232 }
    233 
    234 /*
    235  * discover the tick frequency of the machine
    236  * if something goes wrong, we return 0, an impossible hertz.
    237  */
    238 static int
    239 hertz()
    240 {
    241 	struct itimerval tim;
    242 
    243 	tim.it_interval.tv_sec = 0;
    244 	tim.it_interval.tv_usec = 1;
    245 	tim.it_value.tv_sec = 0;
    246 	tim.it_value.tv_usec = 0;
    247 	setitimer(ITIMER_REAL, &tim, 0);
    248 	setitimer(ITIMER_REAL, 0, &tim);
    249 	if (tim.it_interval.tv_usec < 2)
    250 		return(0);
    251 	return (1000000 / tim.it_interval.tv_usec);
    252 }
    253 
    254 
    255