xref: /linux/tools/perf/util/trace-event-read.c (revision c3f5fd287aa897f710f3305367a1d256c9cf3e83)
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 #define _FILE_OFFSET_BITS 64
22 
23 #include <dirent.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <getopt.h>
28 #include <stdarg.h>
29 #include <sys/types.h>
30 #include <sys/stat.h>
31 #include <sys/wait.h>
32 #include <sys/mman.h>
33 #include <pthread.h>
34 #include <fcntl.h>
35 #include <unistd.h>
36 #include <ctype.h>
37 #include <errno.h>
38 
39 #include "../perf.h"
40 #include "util.h"
41 #include "trace-event.h"
42 
43 static int input_fd;
44 
45 static int read_page;
46 
47 int file_bigendian;
48 int host_bigendian;
49 static int long_size;
50 
51 static unsigned long	page_size;
52 
53 static ssize_t calc_data_size;
54 static bool repipe;
55 
56 /* If it fails, the next read will report it */
57 static void skip(int size)
58 {
59 	lseek(input_fd, size, SEEK_CUR);
60 }
61 
62 static int do_read(int fd, void *buf, int size)
63 {
64 	int rsize = size;
65 
66 	while (size) {
67 		int ret = read(fd, buf, size);
68 
69 		if (ret <= 0)
70 			return -1;
71 
72 		if (repipe) {
73 			int retw = write(STDOUT_FILENO, buf, ret);
74 
75 			if (retw <= 0 || retw != ret)
76 				die("repiping input file");
77 		}
78 
79 		size -= ret;
80 		buf += ret;
81 	}
82 
83 	return rsize;
84 }
85 
86 static int read_or_die(void *data, int size)
87 {
88 	int r;
89 
90 	r = do_read(input_fd, data, size);
91 	if (r <= 0)
92 		die("reading input file (size expected=%d received=%d)",
93 		    size, r);
94 
95 	if (calc_data_size)
96 		calc_data_size += r;
97 
98 	return r;
99 }
100 
101 static unsigned int read4(void)
102 {
103 	unsigned int data;
104 
105 	read_or_die(&data, 4);
106 	return __data2host4(data);
107 }
108 
109 static unsigned long long read8(void)
110 {
111 	unsigned long long data;
112 
113 	read_or_die(&data, 8);
114 	return __data2host8(data);
115 }
116 
117 static char *read_string(void)
118 {
119 	char buf[BUFSIZ];
120 	char *str = NULL;
121 	int size = 0;
122 	off_t r;
123 	char c;
124 
125 	for (;;) {
126 		r = read(input_fd, &c, 1);
127 		if (r < 0)
128 			die("reading input file");
129 
130 		if (!r)
131 			die("no data");
132 
133 		if (repipe) {
134 			int retw = write(STDOUT_FILENO, &c, 1);
135 
136 			if (retw <= 0 || retw != r)
137 				die("repiping input file string");
138 		}
139 
140 		buf[size++] = c;
141 
142 		if (!c)
143 			break;
144 	}
145 
146 	if (calc_data_size)
147 		calc_data_size += size;
148 
149 	str = malloc_or_die(size);
150 	memcpy(str, buf, size);
151 
152 	return str;
153 }
154 
155 static void read_proc_kallsyms(void)
156 {
157 	unsigned int size;
158 	char *buf;
159 
160 	size = read4();
161 	if (!size)
162 		return;
163 
164 	buf = malloc_or_die(size + 1);
165 	read_or_die(buf, size);
166 	buf[size] = '\0';
167 
168 	parse_proc_kallsyms(buf, size);
169 
170 	free(buf);
171 }
172 
173 static void read_ftrace_printk(void)
174 {
175 	unsigned int size;
176 	char *buf;
177 
178 	size = read4();
179 	if (!size)
180 		return;
181 
182 	buf = malloc_or_die(size);
183 	read_or_die(buf, size);
184 
185 	parse_ftrace_printk(buf, size);
186 
187 	free(buf);
188 }
189 
190 static void read_header_files(void)
191 {
192 	unsigned long long size;
193 	char *header_event;
194 	char buf[BUFSIZ];
195 
196 	read_or_die(buf, 12);
197 
198 	if (memcmp(buf, "header_page", 12) != 0)
199 		die("did not read header page");
200 
201 	size = read8();
202 	skip(size);
203 
204 	/*
205 	 * The size field in the page is of type long,
206 	 * use that instead, since it represents the kernel.
207 	 */
208 	long_size = header_page_size_size;
209 
210 	read_or_die(buf, 13);
211 	if (memcmp(buf, "header_event", 13) != 0)
212 		die("did not read header event");
213 
214 	size = read8();
215 	header_event = malloc_or_die(size);
216 	read_or_die(header_event, size);
217 	free(header_event);
218 }
219 
220 static void read_ftrace_file(unsigned long long size)
221 {
222 	char *buf;
223 
224 	buf = malloc_or_die(size);
225 	read_or_die(buf, size);
226 	parse_ftrace_file(buf, size);
227 	free(buf);
228 }
229 
230 static void read_event_file(char *sys, unsigned long long size)
231 {
232 	char *buf;
233 
234 	buf = malloc_or_die(size);
235 	read_or_die(buf, size);
236 	parse_event_file(buf, size, sys);
237 	free(buf);
238 }
239 
240 static void read_ftrace_files(void)
241 {
242 	unsigned long long size;
243 	int count;
244 	int i;
245 
246 	count = read4();
247 
248 	for (i = 0; i < count; i++) {
249 		size = read8();
250 		read_ftrace_file(size);
251 	}
252 }
253 
254 static void read_event_files(void)
255 {
256 	unsigned long long size;
257 	char *sys;
258 	int systems;
259 	int count;
260 	int i,x;
261 
262 	systems = read4();
263 
264 	for (i = 0; i < systems; i++) {
265 		sys = read_string();
266 
267 		count = read4();
268 		for (x=0; x < count; x++) {
269 			size = read8();
270 			read_event_file(sys, size);
271 		}
272 	}
273 }
274 
275 struct cpu_data {
276 	unsigned long long	offset;
277 	unsigned long long	size;
278 	unsigned long long	timestamp;
279 	struct record		*next;
280 	char			*page;
281 	int			cpu;
282 	int			index;
283 	int			page_size;
284 };
285 
286 static struct cpu_data *cpu_data;
287 
288 static void update_cpu_data_index(int cpu)
289 {
290 	cpu_data[cpu].offset += page_size;
291 	cpu_data[cpu].size -= page_size;
292 	cpu_data[cpu].index = 0;
293 }
294 
295 static void get_next_page(int cpu)
296 {
297 	off_t save_seek;
298 	off_t ret;
299 
300 	if (!cpu_data[cpu].page)
301 		return;
302 
303 	if (read_page) {
304 		if (cpu_data[cpu].size <= page_size) {
305 			free(cpu_data[cpu].page);
306 			cpu_data[cpu].page = NULL;
307 			return;
308 		}
309 
310 		update_cpu_data_index(cpu);
311 
312 		/* other parts of the code may expect the pointer to not move */
313 		save_seek = lseek(input_fd, 0, SEEK_CUR);
314 
315 		ret = lseek(input_fd, cpu_data[cpu].offset, SEEK_SET);
316 		if (ret == (off_t)-1)
317 			die("failed to lseek");
318 		ret = read(input_fd, cpu_data[cpu].page, page_size);
319 		if (ret < 0)
320 			die("failed to read page");
321 
322 		/* reset the file pointer back */
323 		lseek(input_fd, save_seek, SEEK_SET);
324 
325 		return;
326 	}
327 
328 	munmap(cpu_data[cpu].page, page_size);
329 	cpu_data[cpu].page = NULL;
330 
331 	if (cpu_data[cpu].size <= page_size)
332 		return;
333 
334 	update_cpu_data_index(cpu);
335 
336 	cpu_data[cpu].page = mmap(NULL, page_size, PROT_READ, MAP_PRIVATE,
337 				  input_fd, cpu_data[cpu].offset);
338 	if (cpu_data[cpu].page == MAP_FAILED)
339 		die("failed to mmap cpu %d at offset 0x%llx",
340 		    cpu, cpu_data[cpu].offset);
341 }
342 
343 static unsigned int type_len4host(unsigned int type_len_ts)
344 {
345 	if (file_bigendian)
346 		return (type_len_ts >> 27) & ((1 << 5) - 1);
347 	else
348 		return type_len_ts & ((1 << 5) - 1);
349 }
350 
351 static unsigned int ts4host(unsigned int type_len_ts)
352 {
353 	if (file_bigendian)
354 		return type_len_ts & ((1 << 27) - 1);
355 	else
356 		return type_len_ts >> 5;
357 }
358 
359 static int calc_index(void *ptr, int cpu)
360 {
361 	return (unsigned long)ptr - (unsigned long)cpu_data[cpu].page;
362 }
363 
364 struct record *trace_peek_data(int cpu)
365 {
366 	struct record *data;
367 	void *page = cpu_data[cpu].page;
368 	int idx = cpu_data[cpu].index;
369 	void *ptr = page + idx;
370 	unsigned long long extend;
371 	unsigned int type_len_ts;
372 	unsigned int type_len;
373 	unsigned int delta;
374 	unsigned int length = 0;
375 
376 	if (cpu_data[cpu].next)
377 		return cpu_data[cpu].next;
378 
379 	if (!page)
380 		return NULL;
381 
382 	if (!idx) {
383 		/* FIXME: handle header page */
384 		if (header_page_ts_size != 8)
385 			die("expected a long long type for timestamp");
386 		cpu_data[cpu].timestamp = data2host8(ptr);
387 		ptr += 8;
388 		switch (header_page_size_size) {
389 		case 4:
390 			cpu_data[cpu].page_size = data2host4(ptr);
391 			ptr += 4;
392 			break;
393 		case 8:
394 			cpu_data[cpu].page_size = data2host8(ptr);
395 			ptr += 8;
396 			break;
397 		default:
398 			die("bad long size");
399 		}
400 		ptr = cpu_data[cpu].page + header_page_data_offset;
401 	}
402 
403 read_again:
404 	idx = calc_index(ptr, cpu);
405 
406 	if (idx >= cpu_data[cpu].page_size) {
407 		get_next_page(cpu);
408 		return trace_peek_data(cpu);
409 	}
410 
411 	type_len_ts = data2host4(ptr);
412 	ptr += 4;
413 
414 	type_len = type_len4host(type_len_ts);
415 	delta = ts4host(type_len_ts);
416 
417 	switch (type_len) {
418 	case RINGBUF_TYPE_PADDING:
419 		if (!delta)
420 			die("error, hit unexpected end of page");
421 		length = data2host4(ptr);
422 		ptr += 4;
423 		length *= 4;
424 		ptr += length;
425 		goto read_again;
426 
427 	case RINGBUF_TYPE_TIME_EXTEND:
428 		extend = data2host4(ptr);
429 		ptr += 4;
430 		extend <<= TS_SHIFT;
431 		extend += delta;
432 		cpu_data[cpu].timestamp += extend;
433 		goto read_again;
434 
435 	case RINGBUF_TYPE_TIME_STAMP:
436 		ptr += 12;
437 		break;
438 	case 0:
439 		length = data2host4(ptr);
440 		ptr += 4;
441 		die("here! length=%d", length);
442 		break;
443 	default:
444 		length = type_len * 4;
445 		break;
446 	}
447 
448 	cpu_data[cpu].timestamp += delta;
449 
450 	data = malloc_or_die(sizeof(*data));
451 	memset(data, 0, sizeof(*data));
452 
453 	data->ts = cpu_data[cpu].timestamp;
454 	data->size = length;
455 	data->data = ptr;
456 	ptr += length;
457 
458 	cpu_data[cpu].index = calc_index(ptr, cpu);
459 	cpu_data[cpu].next = data;
460 
461 	return data;
462 }
463 
464 struct record *trace_read_data(int cpu)
465 {
466 	struct record *data;
467 
468 	data = trace_peek_data(cpu);
469 	cpu_data[cpu].next = NULL;
470 
471 	return data;
472 }
473 
474 ssize_t trace_report(int fd, bool __repipe)
475 {
476 	char buf[BUFSIZ];
477 	char test[] = { 23, 8, 68 };
478 	char *version;
479 	int show_version = 0;
480 	int show_funcs = 0;
481 	int show_printk = 0;
482 	ssize_t size;
483 
484 	calc_data_size = 1;
485 	repipe = __repipe;
486 
487 	input_fd = fd;
488 
489 	read_or_die(buf, 3);
490 	if (memcmp(buf, test, 3) != 0)
491 		die("no trace data in the file");
492 
493 	read_or_die(buf, 7);
494 	if (memcmp(buf, "tracing", 7) != 0)
495 		die("not a trace file (missing 'tracing' tag)");
496 
497 	version = read_string();
498 	if (show_version)
499 		printf("version = %s\n", version);
500 	free(version);
501 
502 	read_or_die(buf, 1);
503 	file_bigendian = buf[0];
504 	host_bigendian = bigendian();
505 
506 	read_or_die(buf, 1);
507 	long_size = buf[0];
508 
509 	page_size = read4();
510 
511 	read_header_files();
512 
513 	read_ftrace_files();
514 	read_event_files();
515 	read_proc_kallsyms();
516 	read_ftrace_printk();
517 
518 	size = calc_data_size - 1;
519 	calc_data_size = 0;
520 	repipe = false;
521 
522 	if (show_funcs) {
523 		print_funcs();
524 		return size;
525 	}
526 	if (show_printk) {
527 		print_printk();
528 		return size;
529 	}
530 
531 	return size;
532 }
533