xref: /linux/tools/perf/util/trace-event-read.c (revision c4ee0af3fa0dc65f690fc908f02b8355f9576ea0)
1 /*
2  * Copyright (C) 2009, Steven Rostedt <srostedt@redhat.com>
3  *
4  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; version 2 of the License (not later!)
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18  *
19  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
20  */
21 #include <dirent.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <getopt.h>
26 #include <stdarg.h>
27 #include <sys/types.h>
28 #include <sys/stat.h>
29 #include <sys/wait.h>
30 #include <sys/mman.h>
31 #include <pthread.h>
32 #include <fcntl.h>
33 #include <unistd.h>
34 #include <errno.h>
35 
36 #include "../perf.h"
37 #include "util.h"
38 #include "trace-event.h"
39 
40 static int input_fd;
41 
42 static ssize_t trace_data_size;
43 static bool repipe;
44 
45 static int __do_read(int fd, void *buf, int size)
46 {
47 	int rsize = size;
48 
49 	while (size) {
50 		int ret = read(fd, buf, size);
51 
52 		if (ret <= 0)
53 			return -1;
54 
55 		if (repipe) {
56 			int retw = write(STDOUT_FILENO, buf, ret);
57 
58 			if (retw <= 0 || retw != ret) {
59 				pr_debug("repiping input file");
60 				return -1;
61 			}
62 		}
63 
64 		size -= ret;
65 		buf += ret;
66 	}
67 
68 	return rsize;
69 }
70 
71 static int do_read(void *data, int size)
72 {
73 	int r;
74 
75 	r = __do_read(input_fd, data, size);
76 	if (r <= 0) {
77 		pr_debug("reading input file (size expected=%d received=%d)",
78 			 size, r);
79 		return -1;
80 	}
81 
82 	trace_data_size += r;
83 
84 	return r;
85 }
86 
87 /* If it fails, the next read will report it */
88 static void skip(int size)
89 {
90 	char buf[BUFSIZ];
91 	int r;
92 
93 	while (size) {
94 		r = size > BUFSIZ ? BUFSIZ : size;
95 		do_read(buf, r);
96 		size -= r;
97 	};
98 }
99 
100 static unsigned int read4(struct pevent *pevent)
101 {
102 	unsigned int data;
103 
104 	if (do_read(&data, 4) < 0)
105 		return 0;
106 	return __data2host4(pevent, data);
107 }
108 
109 static unsigned long long read8(struct pevent *pevent)
110 {
111 	unsigned long long data;
112 
113 	if (do_read(&data, 8) < 0)
114 		return 0;
115 	return __data2host8(pevent, data);
116 }
117 
118 static char *read_string(void)
119 {
120 	char buf[BUFSIZ];
121 	char *str = NULL;
122 	int size = 0;
123 	off_t r;
124 	char c;
125 
126 	for (;;) {
127 		r = read(input_fd, &c, 1);
128 		if (r < 0) {
129 			pr_debug("reading input file");
130 			goto out;
131 		}
132 
133 		if (!r) {
134 			pr_debug("no data");
135 			goto out;
136 		}
137 
138 		if (repipe) {
139 			int retw = write(STDOUT_FILENO, &c, 1);
140 
141 			if (retw <= 0 || retw != r) {
142 				pr_debug("repiping input file string");
143 				goto out;
144 			}
145 		}
146 
147 		buf[size++] = c;
148 
149 		if (!c)
150 			break;
151 	}
152 
153 	trace_data_size += size;
154 
155 	str = malloc(size);
156 	if (str)
157 		memcpy(str, buf, size);
158 out:
159 	return str;
160 }
161 
162 static int read_proc_kallsyms(struct pevent *pevent)
163 {
164 	unsigned int size;
165 	char *buf;
166 
167 	size = read4(pevent);
168 	if (!size)
169 		return 0;
170 
171 	buf = malloc(size + 1);
172 	if (buf == NULL)
173 		return -1;
174 
175 	if (do_read(buf, size) < 0) {
176 		free(buf);
177 		return -1;
178 	}
179 	buf[size] = '\0';
180 
181 	parse_proc_kallsyms(pevent, buf, size);
182 
183 	free(buf);
184 	return 0;
185 }
186 
187 static int read_ftrace_printk(struct pevent *pevent)
188 {
189 	unsigned int size;
190 	char *buf;
191 
192 	/* it can have 0 size */
193 	size = read4(pevent);
194 	if (!size)
195 		return 0;
196 
197 	buf = malloc(size);
198 	if (buf == NULL)
199 		return -1;
200 
201 	if (do_read(buf, size) < 0) {
202 		free(buf);
203 		return -1;
204 	}
205 
206 	parse_ftrace_printk(pevent, buf, size);
207 
208 	free(buf);
209 	return 0;
210 }
211 
212 static int read_header_files(struct pevent *pevent)
213 {
214 	unsigned long long size;
215 	char *header_page;
216 	char buf[BUFSIZ];
217 	int ret = 0;
218 
219 	if (do_read(buf, 12) < 0)
220 		return -1;
221 
222 	if (memcmp(buf, "header_page", 12) != 0) {
223 		pr_debug("did not read header page");
224 		return -1;
225 	}
226 
227 	size = read8(pevent);
228 
229 	header_page = malloc(size);
230 	if (header_page == NULL)
231 		return -1;
232 
233 	if (do_read(header_page, size) < 0) {
234 		pr_debug("did not read header page");
235 		free(header_page);
236 		return -1;
237 	}
238 
239 	if (!pevent_parse_header_page(pevent, header_page, size,
240 				      pevent_get_long_size(pevent))) {
241 		/*
242 		 * The commit field in the page is of type long,
243 		 * use that instead, since it represents the kernel.
244 		 */
245 		pevent_set_long_size(pevent, pevent->header_page_size_size);
246 	}
247 	free(header_page);
248 
249 	if (do_read(buf, 13) < 0)
250 		return -1;
251 
252 	if (memcmp(buf, "header_event", 13) != 0) {
253 		pr_debug("did not read header event");
254 		return -1;
255 	}
256 
257 	size = read8(pevent);
258 	skip(size);
259 
260 	return ret;
261 }
262 
263 static int read_ftrace_file(struct pevent *pevent, unsigned long long size)
264 {
265 	char *buf;
266 
267 	buf = malloc(size);
268 	if (buf == NULL)
269 		return -1;
270 
271 	if (do_read(buf, size) < 0) {
272 		free(buf);
273 		return -1;
274 	}
275 
276 	parse_ftrace_file(pevent, buf, size);
277 	free(buf);
278 	return 0;
279 }
280 
281 static int read_event_file(struct pevent *pevent, char *sys,
282 			    unsigned long long size)
283 {
284 	char *buf;
285 
286 	buf = malloc(size);
287 	if (buf == NULL)
288 		return -1;
289 
290 	if (do_read(buf, size) < 0) {
291 		free(buf);
292 		return -1;
293 	}
294 
295 	parse_event_file(pevent, buf, size, sys);
296 	free(buf);
297 	return 0;
298 }
299 
300 static int read_ftrace_files(struct pevent *pevent)
301 {
302 	unsigned long long size;
303 	int count;
304 	int i;
305 	int ret;
306 
307 	count = read4(pevent);
308 
309 	for (i = 0; i < count; i++) {
310 		size = read8(pevent);
311 		ret = read_ftrace_file(pevent, size);
312 		if (ret)
313 			return ret;
314 	}
315 	return 0;
316 }
317 
318 static int read_event_files(struct pevent *pevent)
319 {
320 	unsigned long long size;
321 	char *sys;
322 	int systems;
323 	int count;
324 	int i,x;
325 	int ret;
326 
327 	systems = read4(pevent);
328 
329 	for (i = 0; i < systems; i++) {
330 		sys = read_string();
331 		if (sys == NULL)
332 			return -1;
333 
334 		count = read4(pevent);
335 
336 		for (x=0; x < count; x++) {
337 			size = read8(pevent);
338 			ret = read_event_file(pevent, sys, size);
339 			if (ret)
340 				return ret;
341 		}
342 	}
343 	return 0;
344 }
345 
346 ssize_t trace_report(int fd, struct pevent **ppevent, bool __repipe)
347 {
348 	char buf[BUFSIZ];
349 	char test[] = { 23, 8, 68 };
350 	char *version;
351 	int show_version = 0;
352 	int show_funcs = 0;
353 	int show_printk = 0;
354 	ssize_t size = -1;
355 	int file_bigendian;
356 	int host_bigendian;
357 	int file_long_size;
358 	int file_page_size;
359 	struct pevent *pevent;
360 	int err;
361 
362 	*ppevent = NULL;
363 
364 	repipe = __repipe;
365 	input_fd = fd;
366 
367 	if (do_read(buf, 3) < 0)
368 		return -1;
369 	if (memcmp(buf, test, 3) != 0) {
370 		pr_debug("no trace data in the file");
371 		return -1;
372 	}
373 
374 	if (do_read(buf, 7) < 0)
375 		return -1;
376 	if (memcmp(buf, "tracing", 7) != 0) {
377 		pr_debug("not a trace file (missing 'tracing' tag)");
378 		return -1;
379 	}
380 
381 	version = read_string();
382 	if (version == NULL)
383 		return -1;
384 	if (show_version)
385 		printf("version = %s\n", version);
386 	free(version);
387 
388 	if (do_read(buf, 1) < 0)
389 		return -1;
390 	file_bigendian = buf[0];
391 	host_bigendian = bigendian();
392 
393 	pevent = read_trace_init(file_bigendian, host_bigendian);
394 	if (pevent == NULL) {
395 		pr_debug("read_trace_init failed");
396 		goto out;
397 	}
398 
399 	if (do_read(buf, 1) < 0)
400 		goto out;
401 	file_long_size = buf[0];
402 
403 	file_page_size = read4(pevent);
404 	if (!file_page_size)
405 		goto out;
406 
407 	pevent_set_long_size(pevent, file_long_size);
408 	pevent_set_page_size(pevent, file_page_size);
409 
410 	err = read_header_files(pevent);
411 	if (err)
412 		goto out;
413 	err = read_ftrace_files(pevent);
414 	if (err)
415 		goto out;
416 	err = read_event_files(pevent);
417 	if (err)
418 		goto out;
419 	err = read_proc_kallsyms(pevent);
420 	if (err)
421 		goto out;
422 	err = read_ftrace_printk(pevent);
423 	if (err)
424 		goto out;
425 
426 	size = trace_data_size;
427 	repipe = false;
428 
429 	if (show_funcs) {
430 		pevent_print_funcs(pevent);
431 	} else if (show_printk) {
432 		pevent_print_printk(pevent);
433 	}
434 
435 	*ppevent = pevent;
436 	pevent = NULL;
437 
438 out:
439 	if (pevent)
440 		pevent_free(pevent);
441 	return size;
442 }
443