tprof.c revision 1.2 
1/*	$NetBSD: tprof.c,v 1.2 2008/01/03 15:01:07 yamt Exp $	*/
2
3/*-
4 * Copyright (c)2008 YAMAMOTO Takashi,
5 * 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 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30#ifndef lint
31__RCSID("$NetBSD: tprof.c,v 1.2 2008/01/03 15:01:07 yamt Exp $");
32#endif /* not lint */
33
34#include <sys/ioctl.h>
35#include <sys/wait.h>
36
37#include <dev/tprof/tprof_ioctl.h>
38
39#include <err.h>
40#include <errno.h>
41#include <fcntl.h>
42#include <inttypes.h>
43#include <pthread.h>
44#include <signal.h>
45#include <stdbool.h>
46#include <stdio.h>
47#include <stdlib.h>
48#include <string.h>
49#include <unistd.h>
50
51#define	_PATH_TPROF	"/dev/tprof"
52
53int devfd;
54int outfd;
55
56static void
57usage(void)
58{
59
60	fprintf(stderr, "%s [options] command ...\n", getprogname());
61	fprintf(stderr, "\n");
62	fprintf(stderr, "-o filename\t"
63	    "output to the file.  [default: -o tprof.out]\n");
64	fprintf(stderr, "-c\t\t"
65	    "output to stdout.  NOTE: the output is a binary stream.\n");
66
67	exit(EXIT_FAILURE);
68}
69
70static void *
71process_samples(void *dummy)
72{
73
74	for (;;) {
75		char buf[4096];
76		const char *cp;
77		ssize_t ssz;
78
79		ssz = read(devfd, buf, sizeof(buf));
80		if (ssz == -1) {
81			err(EXIT_FAILURE, "read");
82		}
83		if (ssz == 0) {
84			break;
85		}
86		cp = buf;
87		while (ssz) {
88			ssize_t wsz;
89
90			wsz = write(outfd, cp, ssz);
91			if (wsz == -1) {
92				err(EXIT_FAILURE, "write");
93			}
94			ssz -= wsz;
95			cp += wsz;
96		}
97	}
98	return NULL;
99}
100
101int
102main(int argc, char *argv[])
103{
104	struct tprof_param param;
105	struct tprof_stat ts;
106	const char *outfile = "tprof.out";
107	bool cflag = false;
108	pid_t pid;
109	pthread_t pt;
110	int error;
111	int ret;
112	int ch;
113	int version;
114
115	while ((ch = getopt(argc, argv, "co:")) != -1) {
116		switch (ch) {
117		case 'c':
118			cflag = true;
119			break;
120		case 'o':
121			outfile = optarg;
122			break;
123		default:
124			usage();
125		}
126	}
127	argc -= optind;
128	argv += optind;
129	if (argc == 0) {
130		usage();
131	}
132
133	if (cflag) {
134		outfd = STDOUT_FILENO;
135	} else {
136		outfd = open(outfile, O_WRONLY | O_CREAT | O_TRUNC, 0666);
137		if (outfd == -1) {
138			err(EXIT_FAILURE, "%s", optarg);
139		}
140	}
141
142	devfd = open(_PATH_TPROF, O_RDWR);
143	if (devfd == -1) {
144		err(EXIT_SUCCESS, "%s", _PATH_TPROF);
145	}
146
147	ret = ioctl(devfd, TPROF_IOC_GETVERSION, &version);
148	if (ret == -1) {
149		err(EXIT_SUCCESS, "TPROF_IOC_GETVERSION");
150	}
151	if (version != TPROF_VERSION) {
152		errx(EXIT_SUCCESS, "version mismatch: version=%d, expected=%d",
153		    version, TPROF_VERSION);
154	}
155
156	memset(&param, 0, sizeof(param));
157	ret = ioctl(devfd, TPROF_IOC_START, &param);
158	if (ret == -1) {
159		err(EXIT_SUCCESS, "TPROF_IOC_START");
160	}
161
162	pid = fork();
163	switch (pid) {
164	case -1:
165		err(EXIT_FAILURE, "fork");
166	case 0:
167		close(devfd);
168		execvp(argv[0], argv);
169		_Exit(EXIT_FAILURE);
170	}
171
172	signal(SIGINT, SIG_IGN);
173
174	error = pthread_create(&pt, NULL, process_samples, NULL);
175	if (error != 0) {
176		errx(1, "pthread_create: %s", strerror(error));
177	}
178
179	for (;;) {
180		int status;
181
182		pid = wait4(-1, &status, 0, NULL);
183		if (pid == -1) {
184			if (errno == ECHILD) {
185				break;
186			}
187			err(EXIT_FAILURE, "wait4");
188		}
189		if (pid != 0 && WIFEXITED(status)) {
190			break;
191		}
192	}
193
194	ret = ioctl(devfd, TPROF_IOC_STOP, NULL);
195	if (ret == -1) {
196		err(EXIT_FAILURE, "TPROF_IOC_STOP");
197	}
198
199	pthread_join(pt, NULL);
200
201	ret = ioctl(devfd, TPROF_IOC_GETSTAT, &ts);
202	if (ret == -1) {
203		err(EXIT_FAILURE, "TPROF_IOC_GETSTAT");
204	}
205
206	fprintf(stderr, "\n%s statistics:\n", getprogname());
207	fprintf(stderr, "\tsample %" PRIu64 "\n", ts.ts_sample);
208	fprintf(stderr, "\toverflow %" PRIu64 "\n", ts.ts_overflow);
209	fprintf(stderr, "\tbuf %" PRIu64 "\n", ts.ts_buf);
210	fprintf(stderr, "\temptybuf %" PRIu64 "\n", ts.ts_emptybuf);
211	fprintf(stderr, "\tdropbuf %" PRIu64 "\n", ts.ts_dropbuf);
212	fprintf(stderr, "\tdropbuf_sample %" PRIu64 "\n", ts.ts_dropbuf_sample);
213
214	exit(EXIT_SUCCESS);
215}
216