xref: /linux/tools/perf/util/trace-event-read.c (revision ce7240e445303de3ca66e6d08f17a2ec278a5bf6)
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 <errno.h>
37 
38 #include "../perf.h"
39 #include "util.h"
40 #include "trace-event.h"
41 
42 static int input_fd;
43 
44 static int read_page;
45 
46 int file_bigendian;
47 int host_bigendian;
48 static int long_size;
49 
50 static unsigned long	page_size;
51 
52 static ssize_t calc_data_size;
53 static bool repipe;
54 
55 static void *malloc_or_die(int size)
56 {
57 	void *ret;
58 
59 	ret = malloc(size);
60 	if (!ret)
61 		die("malloc");
62 	return ret;
63 }
64 
65 static int do_read(int fd, void *buf, int size)
66 {
67 	int rsize = size;
68 
69 	while (size) {
70 		int ret = read(fd, buf, size);
71 
72 		if (ret <= 0)
73 			return -1;
74 
75 		if (repipe) {
76 			int retw = write(STDOUT_FILENO, buf, ret);
77 
78 			if (retw <= 0 || retw != ret)
79 				die("repiping input file");
80 		}
81 
82 		size -= ret;
83 		buf += ret;
84 	}
85 
86 	return rsize;
87 }
88 
89 static int read_or_die(void *data, int size)
90 {
91 	int r;
92 
93 	r = do_read(input_fd, data, size);
94 	if (r <= 0)
95 		die("reading input file (size expected=%d received=%d)",
96 		    size, r);
97 
98 	if (calc_data_size)
99 		calc_data_size += r;
100 
101 	return r;
102 }
103 
104 /* If it fails, the next read will report it */
105 static void skip(int size)
106 {
107 	char buf[BUFSIZ];
108 	int r;
109 
110 	while (size) {
111 		r = size > BUFSIZ ? BUFSIZ : size;
112 		read_or_die(buf, r);
113 		size -= r;
114 	};
115 }
116 
117 static unsigned int read4(void)
118 {
119 	unsigned int data;
120 
121 	read_or_die(&data, 4);
122 	return __data2host4(perf_pevent, data);
123 }
124 
125 static unsigned long long read8(void)
126 {
127 	unsigned long long data;
128 
129 	read_or_die(&data, 8);
130 	return __data2host8(perf_pevent, data);
131 }
132 
133 static char *read_string(void)
134 {
135 	char buf[BUFSIZ];
136 	char *str = NULL;
137 	int size = 0;
138 	off_t r;
139 	char c;
140 
141 	for (;;) {
142 		r = read(input_fd, &c, 1);
143 		if (r < 0)
144 			die("reading input file");
145 
146 		if (!r)
147 			die("no data");
148 
149 		if (repipe) {
150 			int retw = write(STDOUT_FILENO, &c, 1);
151 
152 			if (retw <= 0 || retw != r)
153 				die("repiping input file string");
154 		}
155 
156 		buf[size++] = c;
157 
158 		if (!c)
159 			break;
160 	}
161 
162 	if (calc_data_size)
163 		calc_data_size += size;
164 
165 	str = malloc_or_die(size);
166 	memcpy(str, buf, size);
167 
168 	return str;
169 }
170 
171 static void read_proc_kallsyms(void)
172 {
173 	unsigned int size;
174 	char *buf;
175 
176 	size = read4();
177 	if (!size)
178 		return;
179 
180 	buf = malloc_or_die(size + 1);
181 	read_or_die(buf, size);
182 	buf[size] = '\0';
183 
184 	parse_proc_kallsyms(buf, size);
185 
186 	free(buf);
187 }
188 
189 static void read_ftrace_printk(void)
190 {
191 	unsigned int size;
192 	char *buf;
193 
194 	size = read4();
195 	if (!size)
196 		return;
197 
198 	buf = malloc_or_die(size);
199 	read_or_die(buf, size);
200 
201 	parse_ftrace_printk(buf, size);
202 
203 	free(buf);
204 }
205 
206 static void read_header_files(void)
207 {
208 	unsigned long long size;
209 	char *header_event;
210 	char buf[BUFSIZ];
211 
212 	read_or_die(buf, 12);
213 
214 	if (memcmp(buf, "header_page", 12) != 0)
215 		die("did not read header page");
216 
217 	size = read8();
218 	skip(size);
219 
220 	/*
221 	 * The size field in the page is of type long,
222 	 * use that instead, since it represents the kernel.
223 	 */
224 	long_size = header_page_size_size;
225 
226 	read_or_die(buf, 13);
227 	if (memcmp(buf, "header_event", 13) != 0)
228 		die("did not read header event");
229 
230 	size = read8();
231 	header_event = malloc_or_die(size);
232 	read_or_die(header_event, size);
233 	free(header_event);
234 }
235 
236 static void read_ftrace_file(unsigned long long size)
237 {
238 	char *buf;
239 
240 	buf = malloc_or_die(size);
241 	read_or_die(buf, size);
242 	parse_ftrace_file(buf, size);
243 	free(buf);
244 }
245 
246 static void read_event_file(char *sys, unsigned long long size)
247 {
248 	char *buf;
249 
250 	buf = malloc_or_die(size);
251 	read_or_die(buf, size);
252 	parse_event_file(buf, size, sys);
253 	free(buf);
254 }
255 
256 static void read_ftrace_files(void)
257 {
258 	unsigned long long size;
259 	int count;
260 	int i;
261 
262 	count = read4();
263 
264 	for (i = 0; i < count; i++) {
265 		size = read8();
266 		read_ftrace_file(size);
267 	}
268 }
269 
270 static void read_event_files(void)
271 {
272 	unsigned long long size;
273 	char *sys;
274 	int systems;
275 	int count;
276 	int i,x;
277 
278 	systems = read4();
279 
280 	for (i = 0; i < systems; i++) {
281 		sys = read_string();
282 
283 		count = read4();
284 		for (x=0; x < count; x++) {
285 			size = read8();
286 			read_event_file(sys, size);
287 		}
288 	}
289 }
290 
291 struct cpu_data {
292 	unsigned long long	offset;
293 	unsigned long long	size;
294 	unsigned long long	timestamp;
295 	struct pevent_record	*next;
296 	char			*page;
297 	int			cpu;
298 	int			index;
299 	int			page_size;
300 };
301 
302 static struct cpu_data *cpu_data;
303 
304 static void update_cpu_data_index(int cpu)
305 {
306 	cpu_data[cpu].offset += page_size;
307 	cpu_data[cpu].size -= page_size;
308 	cpu_data[cpu].index = 0;
309 }
310 
311 static void get_next_page(int cpu)
312 {
313 	off_t save_seek;
314 	off_t ret;
315 
316 	if (!cpu_data[cpu].page)
317 		return;
318 
319 	if (read_page) {
320 		if (cpu_data[cpu].size <= page_size) {
321 			free(cpu_data[cpu].page);
322 			cpu_data[cpu].page = NULL;
323 			return;
324 		}
325 
326 		update_cpu_data_index(cpu);
327 
328 		/* other parts of the code may expect the pointer to not move */
329 		save_seek = lseek(input_fd, 0, SEEK_CUR);
330 
331 		ret = lseek(input_fd, cpu_data[cpu].offset, SEEK_SET);
332 		if (ret == (off_t)-1)
333 			die("failed to lseek");
334 		ret = read(input_fd, cpu_data[cpu].page, page_size);
335 		if (ret < 0)
336 			die("failed to read page");
337 
338 		/* reset the file pointer back */
339 		lseek(input_fd, save_seek, SEEK_SET);
340 
341 		return;
342 	}
343 
344 	munmap(cpu_data[cpu].page, page_size);
345 	cpu_data[cpu].page = NULL;
346 
347 	if (cpu_data[cpu].size <= page_size)
348 		return;
349 
350 	update_cpu_data_index(cpu);
351 
352 	cpu_data[cpu].page = mmap(NULL, page_size, PROT_READ, MAP_PRIVATE,
353 				  input_fd, cpu_data[cpu].offset);
354 	if (cpu_data[cpu].page == MAP_FAILED)
355 		die("failed to mmap cpu %d at offset 0x%llx",
356 		    cpu, cpu_data[cpu].offset);
357 }
358 
359 static unsigned int type_len4host(unsigned int type_len_ts)
360 {
361 	if (file_bigendian)
362 		return (type_len_ts >> 27) & ((1 << 5) - 1);
363 	else
364 		return type_len_ts & ((1 << 5) - 1);
365 }
366 
367 static unsigned int ts4host(unsigned int type_len_ts)
368 {
369 	if (file_bigendian)
370 		return type_len_ts & ((1 << 27) - 1);
371 	else
372 		return type_len_ts >> 5;
373 }
374 
375 static int calc_index(void *ptr, int cpu)
376 {
377 	return (unsigned long)ptr - (unsigned long)cpu_data[cpu].page;
378 }
379 
380 struct pevent_record *trace_peek_data(int cpu)
381 {
382 	struct pevent_record *data;
383 	void *page = cpu_data[cpu].page;
384 	int idx = cpu_data[cpu].index;
385 	void *ptr = page + idx;
386 	unsigned long long extend;
387 	unsigned int type_len_ts;
388 	unsigned int type_len;
389 	unsigned int delta;
390 	unsigned int length = 0;
391 
392 	if (cpu_data[cpu].next)
393 		return cpu_data[cpu].next;
394 
395 	if (!page)
396 		return NULL;
397 
398 	if (!idx) {
399 		/* FIXME: handle header page */
400 		if (header_page_ts_size != 8)
401 			die("expected a long long type for timestamp");
402 		cpu_data[cpu].timestamp = data2host8(perf_pevent, ptr);
403 		ptr += 8;
404 		switch (header_page_size_size) {
405 		case 4:
406 			cpu_data[cpu].page_size = data2host4(perf_pevent, ptr);
407 			ptr += 4;
408 			break;
409 		case 8:
410 			cpu_data[cpu].page_size = data2host8(perf_pevent, ptr);
411 			ptr += 8;
412 			break;
413 		default:
414 			die("bad long size");
415 		}
416 		ptr = cpu_data[cpu].page + header_page_data_offset;
417 	}
418 
419 read_again:
420 	idx = calc_index(ptr, cpu);
421 
422 	if (idx >= cpu_data[cpu].page_size) {
423 		get_next_page(cpu);
424 		return trace_peek_data(cpu);
425 	}
426 
427 	type_len_ts = data2host4(perf_pevent, ptr);
428 	ptr += 4;
429 
430 	type_len = type_len4host(type_len_ts);
431 	delta = ts4host(type_len_ts);
432 
433 	switch (type_len) {
434 	case RINGBUF_TYPE_PADDING:
435 		if (!delta)
436 			die("error, hit unexpected end of page");
437 		length = data2host4(perf_pevent, ptr);
438 		ptr += 4;
439 		length *= 4;
440 		ptr += length;
441 		goto read_again;
442 
443 	case RINGBUF_TYPE_TIME_EXTEND:
444 		extend = data2host4(perf_pevent, ptr);
445 		ptr += 4;
446 		extend <<= TS_SHIFT;
447 		extend += delta;
448 		cpu_data[cpu].timestamp += extend;
449 		goto read_again;
450 
451 	case RINGBUF_TYPE_TIME_STAMP:
452 		ptr += 12;
453 		break;
454 	case 0:
455 		length = data2host4(perf_pevent, ptr);
456 		ptr += 4;
457 		die("here! length=%d", length);
458 		break;
459 	default:
460 		length = type_len * 4;
461 		break;
462 	}
463 
464 	cpu_data[cpu].timestamp += delta;
465 
466 	data = malloc_or_die(sizeof(*data));
467 	memset(data, 0, sizeof(*data));
468 
469 	data->ts = cpu_data[cpu].timestamp;
470 	data->size = length;
471 	data->data = ptr;
472 	ptr += length;
473 
474 	cpu_data[cpu].index = calc_index(ptr, cpu);
475 	cpu_data[cpu].next = data;
476 
477 	return data;
478 }
479 
480 struct pevent_record *trace_read_data(int cpu)
481 {
482 	struct pevent_record *data;
483 
484 	data = trace_peek_data(cpu);
485 	cpu_data[cpu].next = NULL;
486 
487 	return data;
488 }
489 
490 ssize_t trace_report(int fd, bool __repipe)
491 {
492 	char buf[BUFSIZ];
493 	char test[] = { 23, 8, 68 };
494 	char *version;
495 	int show_version = 0;
496 	int show_funcs = 0;
497 	int show_printk = 0;
498 	ssize_t size;
499 
500 	calc_data_size = 1;
501 	repipe = __repipe;
502 
503 	input_fd = fd;
504 
505 	read_or_die(buf, 3);
506 	if (memcmp(buf, test, 3) != 0)
507 		die("no trace data in the file");
508 
509 	read_or_die(buf, 7);
510 	if (memcmp(buf, "tracing", 7) != 0)
511 		die("not a trace file (missing 'tracing' tag)");
512 
513 	version = read_string();
514 	if (show_version)
515 		printf("version = %s\n", version);
516 	free(version);
517 
518 	read_or_die(buf, 1);
519 	file_bigendian = buf[0];
520 	host_bigendian = bigendian();
521 
522 	read_trace_init(file_bigendian, host_bigendian);
523 
524 	read_or_die(buf, 1);
525 	long_size = buf[0];
526 
527 	page_size = read4();
528 
529 	read_header_files();
530 
531 	read_ftrace_files();
532 	read_event_files();
533 	read_proc_kallsyms();
534 	read_ftrace_printk();
535 
536 	size = calc_data_size - 1;
537 	calc_data_size = 0;
538 	repipe = false;
539 
540 	if (show_funcs) {
541 		pevent_print_funcs(perf_pevent);
542 		return size;
543 	}
544 	if (show_printk) {
545 		pevent_print_printk(perf_pevent);
546 		return size;
547 	}
548 
549 	return size;
550 }
551