1/*	$NetBSD: kgmon.c,v 1.27 2021/08/14 17:51:20 ryo 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. 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#include <sys/cdefs.h>
33#ifndef lint
34__COPYRIGHT("@(#) Copyright (c) 1983, 1992, 1993\
35 The Regents of the University of California.  All rights reserved.");
36#endif /* not lint */
37
38#ifndef lint
39#if 0
40static char sccsid[] = "from: @(#)kgmon.c	8.1 (Berkeley) 6/6/93";
41#else
42__RCSID("$NetBSD: kgmon.c,v 1.27 2021/08/14 17:51:20 ryo Exp $");
43#endif
44#endif /* not lint */
45
46#include <sys/param.h>
47#include <sys/file.h>
48#include <sys/sysctl.h>
49#include <sys/gmon.h>
50
51#include <ctype.h>
52#include <errno.h>
53#include <kvm.h>
54#include <err.h>
55#include <limits.h>
56#include <nlist.h>
57#include <stdio.h>
58#include <stdlib.h>
59#include <string.h>
60#include <unistd.h>
61
62static struct nlist nl[] = {
63#define	N_GMONPARAM	0
64	{ "__gmonparam", 0, 0, 0, 0 },
65#define	N_PROFHZ	1
66	{ "_profhz", 0, 0, 0, 0 },
67	{ 0, 0, 0, 0, 0 }
68};
69
70struct kvmvars {
71	kvm_t	*kd;
72	struct gmonparam gpm;
73};
74
75static int	ncpu_mib[2] = { CTL_HW, HW_NCPU };
76static int	bflag, cflag_all, hflag, kflag, rflag, pflag;
77static int	debug = 0;
78static void	setprof(struct kvmvars *kvp, int state, int cpuid);
79static void	dumpstate(struct kvmvars *kvp, int cpuid);
80static void	reset(struct kvmvars *kvp, int cpuid);
81static int	openfiles(char *, char *, struct kvmvars *);
82static int	getprof(struct kvmvars *, int);
83static void	kern_readonly(int);
84static int	getprofhz(struct kvmvars *);
85
86int
87main(int argc, char **argv)
88{
89	int ch, mode, disp, accessmode, ncpu, cpuid = -1;
90	struct kvmvars kvmvars;
91	size_t size;
92	char *sys, *kmemf;
93	char on_cpu[sizeof(" on cpuXXXXXXXXX")];
94
95	size = sizeof(ncpu);
96	if (sysctl(ncpu_mib, 2, &ncpu, &size, NULL, 0) < 0)
97		ncpu = 1;
98
99	setprogname(argv[0]);
100	(void)seteuid(getuid());
101	kmemf = NULL;
102	sys = NULL;
103	while ((ch = getopt(argc, argv, "M:N:bc:dhpr")) != -1) {
104		switch((char)ch) {
105
106		case 'M':
107			kmemf = optarg;
108			kflag = 1;
109			break;
110
111		case 'N':
112			sys = optarg;
113			break;
114
115		case 'b':
116			bflag = 1;
117			break;
118
119		case 'c':
120			if (strcmp(optarg, "all") == 0) {
121				cflag_all = 1;
122				cpuid = 0;
123			} else {
124				cpuid = strtol(optarg, NULL, 10);
125				if (cpuid >= ncpu)
126					errx(1, "illegal CPU id %s", optarg);
127			}
128			break;
129
130		case 'h':
131			hflag = 1;
132			break;
133
134		case 'p':
135			pflag = 1;
136			break;
137
138		case 'r':
139			rflag = 1;
140			break;
141
142		case 'd':
143			debug = 1;
144			break;
145
146		default:
147			(void)fprintf(stderr,
148			    "usage: %s [-bdhrp] [-c cpuid] [-M core] [-N system]\n",
149			    getprogname());
150			exit(1);
151		}
152	}
153	argc -= optind;
154	argv += optind;
155
156#define BACKWARD_COMPATIBILITY
157#ifdef	BACKWARD_COMPATIBILITY
158	if (*argv) {
159		sys = *argv;
160		if (*++argv) {
161			kmemf = *argv;
162			++kflag;
163		}
164	}
165#endif
166	accessmode = openfiles(sys, kmemf, &kvmvars);
167
168	do {
169		if (cpuid == -1)
170			on_cpu[0] = '\0';
171		else
172			snprintf(on_cpu, sizeof(on_cpu), " on cpu%d", cpuid);
173
174		mode = getprof(&kvmvars, cpuid);
175		if (hflag)
176			disp = GMON_PROF_OFF;
177		else if (bflag)
178			disp = GMON_PROF_ON;
179		else
180			disp = mode;
181		if (pflag)
182			dumpstate(&kvmvars, cpuid);
183		if (rflag)
184			reset(&kvmvars, cpuid);
185		if (accessmode == O_RDWR)
186			setprof(&kvmvars, disp, cpuid);
187		(void)fprintf(stdout, "%s: kernel profiling is %s%s.\n",
188		    getprogname(), disp == GMON_PROF_OFF ? "off" : "running",
189		    on_cpu);
190
191	} while (cflag_all && ++cpuid < ncpu);
192	return (0);
193}
194
195/*
196 * Check that profiling is enabled and open any ncessary files.
197 */
198static int
199openfiles(char *sys, char *kmemf, struct kvmvars *kvp)
200{
201	int mib[3], state, openmode;
202	size_t size;
203	char errbuf[_POSIX2_LINE_MAX];
204
205	if (!kflag) {
206		mib[0] = CTL_KERN;
207		mib[1] = KERN_PROF;
208		mib[2] = GPROF_STATE;
209		size = sizeof state;
210		if (sysctl(mib, 3, &state, &size, NULL, 0) < 0)
211			err(EXIT_FAILURE, "profiling not defined in kernel");
212		if (!(bflag || hflag || rflag ||
213		    (pflag && state == GMON_PROF_ON)))
214			return (O_RDONLY);
215		(void)seteuid(0);
216		if (sysctl(mib, 3, NULL, NULL, &state, size) >= 0)
217			return (O_RDWR);
218		(void)seteuid(getuid());
219		kern_readonly(state);
220		return (O_RDONLY);
221	}
222	openmode = (bflag || hflag || pflag || rflag) ? O_RDWR : O_RDONLY;
223	kvp->kd = kvm_openfiles(sys, kmemf, NULL, openmode, errbuf);
224	if (kvp->kd == NULL) {
225		if (openmode == O_RDWR) {
226			openmode = O_RDONLY;
227			kvp->kd = kvm_openfiles(sys, kmemf, NULL, O_RDONLY,
228			    errbuf);
229		}
230		if (kvp->kd == NULL)
231			errx(EXIT_FAILURE, "kvm_openfiles: %s", errbuf);
232		kern_readonly(GMON_PROF_ON);
233	}
234	if (kvm_nlist(kvp->kd, nl) < 0)
235		errx(EXIT_FAILURE, "%s: no namelist", sys);
236	if (!nl[N_GMONPARAM].n_value)
237		errx(EXIT_FAILURE, "profiling not defined in kernel");
238	return (openmode);
239}
240
241/*
242 * Suppress options that require a writable kernel.
243 */
244static void
245kern_readonly(int mode)
246{
247
248	(void)fprintf(stderr, "%s: kernel read-only: ", getprogname());
249	if (pflag && mode == GMON_PROF_ON)
250		(void)fprintf(stderr, "data may be inconsistent\n");
251	if (rflag)
252		(void)fprintf(stderr, "-r suppressed\n");
253	if (bflag)
254		(void)fprintf(stderr, "-b suppressed\n");
255	if (hflag)
256		(void)fprintf(stderr, "-h suppressed\n");
257	rflag = bflag = hflag = 0;
258}
259
260/*
261 * Get the state of kernel profiling.
262 */
263static int
264getprof(struct kvmvars *kvp, int cpuid)
265{
266	int mib[5], miblen, mibparam;
267	size_t size;
268
269	if (kflag) {
270		size = kvm_read(kvp->kd, nl[N_GMONPARAM].n_value, &kvp->gpm,
271		    sizeof kvp->gpm);
272	} else {
273		mib[0] = CTL_KERN;
274		mib[1] = KERN_PROF;
275		if (cpuid < 0) {
276			mibparam = 2;
277			miblen = 3;
278		} else {
279			mib[2] = GPROF_PERCPU;
280			mib[3] = cpuid;
281			mibparam = 4;
282			miblen = 5;
283		}
284		mib[mibparam] = GPROF_GMONPARAM;
285		size = sizeof kvp->gpm;
286		if (sysctl(mib, miblen, &kvp->gpm, &size, NULL, 0) < 0)
287			size = 0;
288	}
289	if (size != sizeof kvp->gpm)
290		errx(EXIT_FAILURE, "cannot get gmonparam: %s",
291		    kflag ? kvm_geterr(kvp->kd) : strerror(errno));
292	return (kvp->gpm.state);
293}
294
295/*
296 * Enable or disable kernel profiling according to the state variable.
297 */
298static void
299setprof(struct kvmvars *kvp, int state, int cpuid)
300{
301	struct gmonparam *p = (struct gmonparam *)nl[N_GMONPARAM].n_value;
302	int mib[5], miblen, mibparam, oldstate;
303	size_t sz;
304
305	sz = sizeof(state);
306	if (!kflag) {
307		mib[0] = CTL_KERN;
308		mib[1] = KERN_PROF;
309		if (cpuid < 0) {
310			mibparam = 2;
311			miblen = 3;
312		} else {
313			mib[2] = GPROF_PERCPU;
314			mib[3] = cpuid;
315			mibparam = 4;
316			miblen = 5;
317		}
318		mib[mibparam] = GPROF_STATE;
319		if (sysctl(mib, miblen, &oldstate, &sz, NULL, 0) < 0)
320			goto bad;
321		if (oldstate == state)
322			return;
323		(void)seteuid(0);
324		if (sysctl(mib, miblen, NULL, NULL, &state, sz) >= 0) {
325			(void)seteuid(getuid());
326			return;
327		}
328		(void)seteuid(getuid());
329	} else if ((size_t)kvm_write(kvp->kd, (u_long)&p->state, (void *)&state, sz)
330	    == sz)
331		return;
332bad:
333	warnx("cannot turn profiling %s", state == GMON_PROF_OFF ?
334	    "off" : "on");
335}
336
337/*
338 * Build the gmon.out file.
339 */
340static void
341dumpstate(struct kvmvars *kvp, int cpuid)
342{
343	FILE *fp;
344	struct rawarc rawarc;
345	struct tostruct *tos;
346	u_long frompc;
347	u_short *froms, *tickbuf;
348	int mib[5], miblen, mibparam;
349	size_t i;
350	struct gmonhdr h;
351	int fromindex, endfrom, toindex;
352	size_t kcountsize;
353	char gmon_out[sizeof("gmon-XXXXXXXXXXX.out")];
354
355	mib[0] = CTL_KERN;
356	mib[1] = KERN_PROF;
357	if (cpuid < 0) {
358		mibparam = 2;
359		miblen = 3;
360	} else {
361		mib[2] = GPROF_PERCPU;
362		mib[3] = cpuid;
363		mibparam = 4;
364		miblen = 5;
365	}
366
367	setprof(kvp, GMON_PROF_OFF, cpuid);
368	if (cpuid < 0)
369		strlcpy(gmon_out, "gmon.out", sizeof(gmon_out));
370	else
371		snprintf(gmon_out, sizeof(gmon_out), "gmon-%d.out", cpuid);
372
373	fp = fopen(gmon_out, "w");
374	if (fp == NULL) {
375		warn("cannot open `%s'", gmon_out);
376		return;
377	}
378
379	/*
380	 * Build the gmon header and write it to a file.
381	 */
382	bzero(&h, sizeof(h));
383	h.lpc = kvp->gpm.lowpc;
384	h.hpc = kvp->gpm.highpc;
385	h.ncnt = kvp->gpm.kcountsize + sizeof(h);
386	h.version = GMONVERSION;
387	h.profrate = getprofhz(kvp);
388	if (fwrite(&h, sizeof(h), 1, fp) != 1)
389		err(EXIT_FAILURE, "writing header to gmon.out");
390
391	kcountsize = (size_t)kvp->gpm.kcountsize;
392
393	/*
394	 * Write out the tick buffer.
395	 */
396	if ((tickbuf = malloc(kcountsize)) == NULL)
397		err(EXIT_FAILURE, "Cannot allocate %zu kcount space",
398		    kcountsize);
399	if (kflag) {
400		i = kvm_read(kvp->kd, (u_long)kvp->gpm.kcount, tickbuf,
401		    kcountsize);
402	} else {
403		mib[mibparam] = GPROF_COUNT;
404		i = kcountsize;
405		if (sysctl(mib, miblen, tickbuf, &i, NULL, 0) < 0)
406			i = 0;
407	}
408	if (i != kcountsize)
409		errx(EXIT_FAILURE, "read ticks: read %zu, got %zu: %s",
410		    kcountsize, i,
411		    kflag ? kvm_geterr(kvp->kd) : strerror(errno));
412	if ((fwrite(tickbuf, kcountsize, 1, fp)) != 1)
413		err(EXIT_FAILURE, "writing ticks to gmon.out");
414	free(tickbuf);
415
416	/*
417	 * Write out the arc info.
418	 */
419	if ((froms = malloc((size_t)kvp->gpm.fromssize)) == NULL)
420		err(EXIT_FAILURE, "cannot allocate %zu froms space",
421		    (size_t)kvp->gpm.fromssize);
422	if (kflag) {
423		i = kvm_read(kvp->kd, (u_long)kvp->gpm.froms, froms,
424		    (size_t)kvp->gpm.fromssize);
425	} else {
426		mib[mibparam] = GPROF_FROMS;
427		i = kvp->gpm.fromssize;
428		if (sysctl(mib, miblen, froms, &i, NULL, 0) < 0)
429			i = 0;
430	}
431	if (i != kvp->gpm.fromssize)
432		errx(EXIT_FAILURE, "read froms: read %lu, got %lu: %s",
433		    kvp->gpm.fromssize, (u_long)i,
434		    kflag ? kvm_geterr(kvp->kd) : strerror(errno));
435	if ((tos = malloc((size_t)kvp->gpm.tossize)) == NULL)
436		err(EXIT_FAILURE, "cannot allocate %zu tos space",
437		    (size_t)kvp->gpm.tossize);
438	if (kflag) {
439		i = kvm_read(kvp->kd, (u_long)kvp->gpm.tos, (void *)tos,
440		    (size_t)kvp->gpm.tossize);
441	} else {
442		mib[mibparam] = GPROF_TOS;
443		i = kvp->gpm.tossize;
444		if (sysctl(mib, miblen, tos, &i, NULL, 0) < 0)
445			i = 0;
446	}
447	if (i != kvp->gpm.tossize)
448		errx(EXIT_FAILURE, "read tos: read %zu, got %zu: %s",
449		    (size_t)kvp->gpm.tossize, i,
450		    kflag ? kvm_geterr(kvp->kd) : strerror(errno));
451	if (debug)
452		(void)fprintf(stderr, "%s: lowpc 0x%lx, textsize 0x%lx\n",
453		     getprogname(), kvp->gpm.lowpc, kvp->gpm.textsize);
454	endfrom = kvp->gpm.fromssize / sizeof(*froms);
455	for (fromindex = 0; fromindex < endfrom; ++fromindex) {
456		if (froms[fromindex] == 0)
457			continue;
458		frompc = (u_long)kvp->gpm.lowpc +
459		    (fromindex * kvp->gpm.hashfraction * sizeof(*froms));
460		for (toindex = froms[fromindex]; toindex != 0;
461		   toindex = tos[toindex].link) {
462			if (debug)
463			    (void)fprintf(stderr,
464			    "%s: [mcleanup] frompc 0x%lx selfpc 0x%lx count %ld\n",
465			    getprogname(), frompc, tos[toindex].selfpc,
466			    tos[toindex].count);
467			rawarc.raw_frompc = frompc;
468			rawarc.raw_selfpc = (u_long)tos[toindex].selfpc;
469			rawarc.raw_count = tos[toindex].count;
470			if (fwrite(&rawarc, sizeof(rawarc), 1,fp) != 1){
471				err(EXIT_FAILURE,
472				    "writing raw arc to gmon.out");
473			}
474		}
475	}
476	free(tos);
477	(void)fclose(fp);
478}
479
480/*
481 * Get the profiling rate.
482 */
483static int
484getprofhz(struct kvmvars *kvp)
485{
486	int mib[2], profrate;
487	size_t size;
488	struct clockinfo clockrate;
489
490	if (kflag) {
491		profrate = 1;
492		if (kvm_read(kvp->kd, nl[N_PROFHZ].n_value, &profrate,
493		    sizeof profrate) != sizeof profrate)
494			warnx("get clockrate: %s", kvm_geterr(kvp->kd));
495		return (profrate);
496	}
497	mib[0] = CTL_KERN;
498	mib[1] = KERN_CLOCKRATE;
499	clockrate.profhz = 1;
500	size = sizeof clockrate;
501	if (sysctl(mib, 2, &clockrate, &size, NULL, 0) < 0)
502		warn("get clockrate");
503	return (clockrate.profhz);
504}
505
506/*
507 * Reset the kernel profiling date structures.
508 */
509static void
510reset(struct kvmvars *kvp, int cpuid)
511{
512	char *zbuf;
513	size_t biggest;
514	int mib[5], miblen, mibparam;
515
516	mib[0] = CTL_KERN;
517	mib[1] = KERN_PROF;
518	if (cpuid < 0) {
519		mibparam = 2;
520		miblen = 3;
521	} else {
522		mib[2] = GPROF_PERCPU;
523		mib[3] = cpuid;
524		mibparam = 4;
525		miblen = 5;
526	}
527
528	setprof(kvp, GMON_PROF_OFF, cpuid);
529
530	biggest = (size_t)kvp->gpm.kcountsize;
531	if ((size_t)kvp->gpm.fromssize > biggest)
532		biggest = (size_t)kvp->gpm.fromssize;
533	if ((size_t)kvp->gpm.tossize > biggest)
534		biggest = (size_t)kvp->gpm.tossize;
535	if ((zbuf = malloc(biggest)) == NULL)
536		err(EXIT_FAILURE, "cannot allocate zbuf space");
537	(void)memset(zbuf, 0, biggest);
538	if (kflag) {
539		if ((size_t)kvm_write(kvp->kd, (u_long)kvp->gpm.kcount, zbuf,
540		    (size_t)kvp->gpm.kcountsize) != kvp->gpm.kcountsize)
541			errx(EXIT_FAILURE, "tickbuf zero: %s",
542			     kvm_geterr(kvp->kd));
543		if ((size_t)kvm_write(kvp->kd, (u_long)kvp->gpm.froms, zbuf,
544		    (size_t)kvp->gpm.fromssize) != kvp->gpm.fromssize)
545			errx(EXIT_FAILURE, "froms zero: %s",
546			     kvm_geterr(kvp->kd));
547		if ((size_t)kvm_write(kvp->kd, (u_long)kvp->gpm.tos, zbuf,
548		    (size_t)kvp->gpm.tossize) != kvp->gpm.tossize)
549			errx(EXIT_FAILURE, "tos zero: %s", kvm_geterr(kvp->kd));
550		free(zbuf);
551		return;
552	}
553	(void)seteuid(0);
554	mib[mibparam] = GPROF_COUNT;
555	if (sysctl(mib, miblen, NULL, NULL, zbuf, (size_t)kvp->gpm.kcountsize) < 0)
556		err(EXIT_FAILURE, "tickbuf zero");
557	mib[mibparam] = GPROF_FROMS;
558	if (sysctl(mib, miblen, NULL, NULL, zbuf, (size_t)kvp->gpm.fromssize) < 0)
559		err(EXIT_FAILURE, "froms zero");
560	mib[mibparam] = GPROF_TOS;
561	if (sysctl(mib, miblen, NULL, NULL, zbuf, (size_t)kvp->gpm.tossize) < 0)
562		err(EXIT_FAILURE, "tos zero");
563	(void)seteuid(getuid());
564	free(zbuf);
565}
566