minix/lib/libc/gmon/gmon.c

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/* $NetBSD: gmon.c,v 1.34 2012/03/13 21:13:37 christos Exp $ */
/*
* Copyright (c) 2003, 2004 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Nathan J. Williams for Wasabi Systems, Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
/*-
* Copyright (c) 1983, 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
#if !defined(lint) && defined(LIBC_SCCS)
#if 0
static char sccsid[] = "@(#)gmon.c 8.1 (Berkeley) 6/4/93";
#else
__RCSID("$NetBSD: gmon.c,v 1.34 2012/03/13 21:13:37 christos Exp $");
#endif
#endif
#include "namespace.h"
#include <sys/param.h>
#include <sys/time.h>
#include <sys/gmon.h>
#include <sys/mman.h>
#include <sys/sysctl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <limits.h>
#include <unistd.h>
#include <err.h>
#include "extern.h"
#include "reentrant.h"
struct gmonparam _gmonparam = { .state = GMON_PROF_OFF };
#ifdef _REENTRANT
struct gmonparam *_gmonfree;
struct gmonparam *_gmoninuse;
mutex_t _gmonlock = MUTEX_INITIALIZER;
thread_key_t _gmonkey;
struct gmonparam _gmondummy;
#endif
static u_int s_scale;
/* see profil(2) where this is describe (incorrectly) */
#define SCALE_1_TO_1 0x10000L
void moncontrol(int);
void monstartup(u_long, u_long);
void _mcleanup(void);
static int hertz(void);
#ifdef _REENTRANT
static void _m_gmon_destructor(void *);
struct gmonparam *_m_gmon_alloc(void)
__attribute__((__no_instrument_function__));
static void _m_gmon_merge(void);
static void _m_gmon_merge_two(struct gmonparam *, struct gmonparam *);
#endif
void
monstartup(u_long lowpc, u_long highpc)
{
u_long o;
char *cp;
struct gmonparam *p = &_gmonparam;
/*
* round lowpc and highpc to multiples of the density we're using
* so the rest of the scaling (here and in gprof) stays in ints.
*/
p->lowpc = rounddown(lowpc, HISTFRACTION * sizeof(HISTCOUNTER));
p->highpc = roundup(highpc, HISTFRACTION * sizeof(HISTCOUNTER));
p->textsize = p->highpc - p->lowpc;
p->kcountsize = p->textsize / HISTFRACTION;
p->hashfraction = HASHFRACTION;
p->fromssize = p->textsize / p->hashfraction;
p->tolimit = p->textsize * ARCDENSITY / 100;
if (p->tolimit < MINARCS)
p->tolimit = MINARCS;
else if (p->tolimit > MAXARCS)
p->tolimit = MAXARCS;
p->tossize = p->tolimit * sizeof(struct tostruct);
cp = sbrk((intptr_t)(p->kcountsize + p->fromssize + p->tossize));
if (cp == (char *)-1) {
warnx("%s: out of memory", __func__);
return;
}
#ifdef notdef
(void)memset(cp, 0, p->kcountsize + p->fromssize + p->tossize);
#endif
p->tos = (struct tostruct *)(void *)cp;
cp += (size_t)p->tossize;
p->kcount = (u_short *)(void *)cp;
cp += (size_t)p->kcountsize;
p->froms = (u_short *)(void *)cp;
__minbrk = sbrk((intptr_t)0);
p->tos[0].link = 0;
o = p->highpc - p->lowpc;
if (p->kcountsize < o) {
#ifndef notdef
s_scale = ((float)p->kcountsize / o ) * SCALE_1_TO_1;
#else /* avoid floating point */
u_long quot = o / p->kcountsize;
if (quot >= 0x10000)
s_scale = 1;
else if (quot >= 0x100)
s_scale = 0x10000 / quot;
else if (o >= 0x800000)
s_scale = 0x1000000 / (o / (p->kcountsize >> 8));
else
s_scale = 0x1000000 / ((o << 8) / p->kcountsize);
#endif
} else
s_scale = SCALE_1_TO_1;
#ifdef _REENTRANT
_gmondummy.state = GMON_PROF_BUSY;
thr_keycreate(&_gmonkey, _m_gmon_destructor);
#endif
moncontrol(1);
}
#ifdef _REENTRANT
static void
_m_gmon_destructor(void *arg)
{
struct gmonparam *p = arg, *q, **prev;
if (p == &_gmondummy)
return;
thr_setspecific(_gmonkey, &_gmondummy);
mutex_lock(&_gmonlock);
/* XXX eww, linear list traversal. */
for (q = _gmoninuse, prev = &_gmoninuse;
q != NULL;
prev = (struct gmonparam **)(void *)&q->kcount, /* XXX */
q = (struct gmonparam *)(void *)q->kcount) {
if (q == p)
*prev = (struct gmonparam *)(void *)q->kcount;
}
p->kcount = (u_short *)(void *)_gmonfree;
_gmonfree = p;
mutex_unlock(&_gmonlock);
thr_setspecific(_gmonkey, NULL);
}
struct gmonparam *
_m_gmon_alloc(void)
{
struct gmonparam *p;
char *cp;
mutex_lock(&_gmonlock);
if (_gmonfree != NULL) {
p = _gmonfree;
_gmonfree = (struct gmonparam *)(void *)p->kcount;
p->kcount = (u_short *)(void *)_gmoninuse;
_gmoninuse = p;
} else {
mutex_unlock(&_gmonlock);
cp = mmap(NULL,
(size_t)(sizeof (struct gmonparam) +
_gmonparam.fromssize + _gmonparam.tossize),
PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, -1, (off_t)0);
p = (void *)cp;
*p = _gmonparam;
p->kcount = NULL;
cp += sizeof (struct gmonparam);
memset(cp, 0, (size_t)(p->fromssize + p->tossize));
p->froms = (u_short *)(void *)cp;
p->tos = (struct tostruct *)(void *)(cp + p->fromssize);
mutex_lock(&_gmonlock);
p->kcount = (u_short *)(void *)_gmoninuse;
_gmoninuse = p;
}
mutex_unlock(&_gmonlock);
thr_setspecific(_gmonkey, p);
return p;
}
static void
_m_gmon_merge_two(struct gmonparam *p, struct gmonparam *q)
{
u_long fromindex;
u_short *frompcindex, qtoindex, toindex;
u_long selfpc;
u_long endfrom;
long count;
struct tostruct *top;
endfrom = (q->fromssize / sizeof(*q->froms));
for (fromindex = 0; fromindex < endfrom; fromindex++) {
if (q->froms[fromindex] == 0)
continue;
for (qtoindex = q->froms[fromindex]; qtoindex != 0;
qtoindex = q->tos[qtoindex].link) {
selfpc = q->tos[qtoindex].selfpc;
count = q->tos[qtoindex].count;
/* cribbed from mcount */
frompcindex = &p->froms[fromindex];
toindex = *frompcindex;
if (toindex == 0) {
/*
* first time traversing this arc
*/
toindex = ++p->tos[0].link;
if (toindex >= p->tolimit)
/* halt further profiling */
goto overflow;
*frompcindex = (u_short)toindex;
top = &p->tos[(size_t)toindex];
top->selfpc = selfpc;
top->count = count;
top->link = 0;
goto done;
}
top = &p->tos[(size_t)toindex];
if (top->selfpc == selfpc) {
/*
* arc at front of chain; usual case.
*/
top->count+= count;
goto done;
}
/*
* have to go looking down chain for it.
* top points to what we are looking at,
* we know it is not at the head of the chain.
*/
for (; /* goto done */; ) {
if (top->link == 0) {
/*
* top is end of the chain and
* none of the chain had
* top->selfpc == selfpc. so
* we allocate a new tostruct
* and link it to the head of
* the chain.
*/
toindex = ++p->tos[0].link;
if (toindex >= p->tolimit)
goto overflow;
top = &p->tos[(size_t)toindex];
top->selfpc = selfpc;
top->count = count;
top->link = *frompcindex;
*frompcindex = (u_short)toindex;
goto done;
}
/*
* otherwise, check the next arc on the chain.
*/
top = &p->tos[top->link];
if (top->selfpc == selfpc) {
/*
* there it is.
* add to its count.
*/
top->count += count;
goto done;
}
}
done: ;
}
}
overflow: ;
}
static void
_m_gmon_merge(void)
{
struct gmonparam *q;
mutex_lock(&_gmonlock);
for (q = _gmonfree; q != NULL;
q = (struct gmonparam *)(void *)q->kcount)
_m_gmon_merge_two(&_gmonparam, q);
for (q = _gmoninuse; q != NULL;
q = (struct gmonparam *)(void *)q->kcount) {
q->state = GMON_PROF_OFF;
_m_gmon_merge_two(&_gmonparam, q);
}
mutex_unlock(&_gmonlock);
}
#endif
void
_mcleanup(void)
{
int fd;
int fromindex;
int endfrom;
u_long frompc;
int toindex;
struct rawarc rawarc;
struct gmonparam *p = &_gmonparam;
struct gmonhdr gmonhdr, *hdr;
struct clockinfo clockinfo;
#ifndef __minix
int mib[2];
size_t size;
#endif
char *profdir;
const char *proffile;
char buf[PATH_MAX];
#ifdef DEBUG
int logfd, len;
char buf2[200];
#endif
/*
* We disallow writing to the profiling file, if we are a
* set{u,g}id program and our effective {u,g}id does not match
* our real one.
*/
if (issetugid() && (geteuid() != getuid() || getegid() != getgid())) {
warnx("%s: Profiling of set{u,g}id binaries is not"
" allowed", __func__);
return;
}
if (p->state == GMON_PROF_ERROR)
warnx("%s: tos overflow", __func__);
#ifdef __minix
clockinfo.profhz = sysconf(_SC_CLK_TCK);
#else /* !__minix */
size = sizeof(clockinfo);
mib[0] = CTL_KERN;
mib[1] = KERN_CLOCKRATE;
if (sysctl(mib, 2, &clockinfo, &size, NULL, 0) < 0) {
/*
* Best guess
*/
clockinfo.profhz = hertz();
} else if (clockinfo.profhz == 0) {
if (clockinfo.hz != 0)
clockinfo.profhz = clockinfo.hz;
else
clockinfo.profhz = hertz();
}
#endif /* !__minix */
moncontrol(0);
if ((profdir = getenv("PROFDIR")) != NULL) {
/* If PROFDIR contains a null value, no profiling
output is produced */
if (*profdir == '\0')
return;
if (snprintf(buf, sizeof buf, "%s/%d.%s",
profdir, getpid(), getprogname()) >= (int)(sizeof buf)) {
warnx("%s: internal buffer overflow, PROFDIR too long",
__func__);
return;
}
proffile = buf;
} else {
proffile = "gmon.out";
}
fd = open(proffile , O_CREAT|O_TRUNC|O_WRONLY, 0666);
if (fd < 0) {
warn("%s: Cannot open `%s'", __func__, proffile);
return;
}
#ifdef DEBUG
logfd = open("gmon.log", O_CREAT|O_TRUNC|O_WRONLY, 0664);
if (logfd < 0) {
warn("%s: Cannot open `%s'", __func__, "gmon.log");
(void)close(fd);
return;
}
len = snprintf(buf2, sizeof buf2, "[mcleanup1] kcount %p ssiz %lu\n",
p->kcount, p->kcountsize);
(void)write(logfd, buf2, (size_t)len);
#endif
#ifdef _REENTRANT
_m_gmon_merge();
#endif
hdr = (struct gmonhdr *)&gmonhdr;
hdr->lpc = p->lowpc;
hdr->hpc = p->highpc;
hdr->ncnt = (int)(p->kcountsize + sizeof(gmonhdr));
hdr->version = GMONVERSION;
hdr->profrate = clockinfo.profhz;
(void)write(fd, hdr, sizeof *hdr);
(void)write(fd, p->kcount, (size_t)p->kcountsize);
endfrom = (int)(p->fromssize / sizeof(*p->froms));
for (fromindex = 0; fromindex < endfrom; fromindex++) {
if (p->froms[fromindex] == 0)
continue;
frompc = p->lowpc;
frompc += fromindex * p->hashfraction * sizeof(*p->froms);
for (toindex = p->froms[fromindex]; toindex != 0;
toindex = p->tos[toindex].link) {
#ifdef DEBUG
len = snprintf(buf2, sizeof buf2,
"[mcleanup2] frompc 0x%lx selfpc 0x%lx count %lu\n" ,
(u_long)frompc, (u_long)p->tos[toindex].selfpc,
(u_long)p->tos[toindex].count);
(void)write(logfd, buf2, (size_t)len);
#endif
rawarc.raw_frompc = frompc;
rawarc.raw_selfpc = p->tos[toindex].selfpc;
rawarc.raw_count = p->tos[toindex].count;
(void)write(fd, &rawarc, sizeof rawarc);
}
}
(void)close(fd);
#ifdef DEBUG
(void)close(logfd);
#endif
}
/*
* Control profiling
* profiling is what mcount checks to see if
* all the data structures are ready.
*/
void
moncontrol(int mode)
{
struct gmonparam *p = &_gmonparam;
if (mode) {
/* start */
profil((char *)(void *)p->kcount, (size_t)p->kcountsize,
p->lowpc, s_scale);
p->state = GMON_PROF_ON;
} else {
/* stop */
profil(NULL, 0, (u_long)0, 0);
p->state = GMON_PROF_OFF;
}
}
#ifndef __minix
/*
* discover the tick frequency of the machine
* if something goes wrong, we return 0, an impossible hertz.
*/
static int
hertz(void)
{
struct itimerspec tim;
timer_t t;
int rv = 0;
tim.it_interval.tv_sec = 0;
tim.it_interval.tv_nsec = 1;
tim.it_value.tv_sec = 0;
tim.it_value.tv_nsec = 0;
if (timer_create(CLOCK_REALTIME, NULL, &t) == -1)
return 0;
if (timer_settime(t, 0, &tim, NULL) == -1)
goto out;
if (timer_gettime(t, &tim) == -1)
goto out;
if (tim.it_interval.tv_nsec < 2)
goto out;
rv = (int)(1000000000LL / tim.it_interval.tv_nsec);
out:
(void)timer_delete(t);
return rv;
}
#endif /* !__minix */