1 /*
2 * Copyright (C) 2008,2009, 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 "util.h"
22 #include <dirent.h>
23 #include <mntent.h>
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <string.h>
27 #include <stdarg.h>
28 #include <sys/types.h>
29 #include <sys/stat.h>
30 #include <sys/wait.h>
31 #include <pthread.h>
32 #include <fcntl.h>
33 #include <unistd.h>
34 #include <errno.h>
35 #include <stdbool.h>
36 #include <linux/list.h>
37 #include <linux/kernel.h>
38
39 #include "../perf.h"
40 #include "trace-event.h"
41 #include <api/fs/tracing_path.h>
42 #include "evsel.h"
43 #include "debug.h"
44
45 #define VERSION "0.5"
46
47 static int output_fd;
48
49
bigendian(void)50 int bigendian(void)
51 {
52 unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
53 unsigned int *ptr;
54
55 ptr = (unsigned int *)(void *)str;
56 return *ptr == 0x01020304;
57 }
58
59 /* unfortunately, you can not stat debugfs or proc files for size */
record_file(const char * file,ssize_t hdr_sz)60 static int record_file(const char *file, ssize_t hdr_sz)
61 {
62 unsigned long long size = 0;
63 char buf[BUFSIZ], *sizep;
64 off_t hdr_pos = lseek(output_fd, 0, SEEK_CUR);
65 int r, fd;
66 int err = -EIO;
67
68 fd = open(file, O_RDONLY);
69 if (fd < 0) {
70 pr_debug("Can't read '%s'", file);
71 return -errno;
72 }
73
74 /* put in zeros for file size, then fill true size later */
75 if (hdr_sz) {
76 if (write(output_fd, &size, hdr_sz) != hdr_sz)
77 goto out;
78 }
79
80 do {
81 r = read(fd, buf, BUFSIZ);
82 if (r > 0) {
83 size += r;
84 if (write(output_fd, buf, r) != r)
85 goto out;
86 }
87 } while (r > 0);
88
89 /* ugh, handle big-endian hdr_size == 4 */
90 sizep = (char*)&size;
91 if (bigendian())
92 sizep += sizeof(u64) - hdr_sz;
93
94 if (hdr_sz && pwrite(output_fd, sizep, hdr_sz, hdr_pos) < 0) {
95 pr_debug("writing file size failed\n");
96 goto out;
97 }
98
99 err = 0;
100 out:
101 close(fd);
102 return err;
103 }
104
record_header_files(void)105 static int record_header_files(void)
106 {
107 char *path;
108 struct stat st;
109 int err = -EIO;
110
111 path = get_tracing_file("events/header_page");
112 if (!path) {
113 pr_debug("can't get tracing/events/header_page");
114 return -ENOMEM;
115 }
116
117 if (stat(path, &st) < 0) {
118 pr_debug("can't read '%s'", path);
119 goto out;
120 }
121
122 if (write(output_fd, "header_page", 12) != 12) {
123 pr_debug("can't write header_page\n");
124 goto out;
125 }
126
127 if (record_file(path, 8) < 0) {
128 pr_debug("can't record header_page file\n");
129 goto out;
130 }
131
132 put_tracing_file(path);
133
134 path = get_tracing_file("events/header_event");
135 if (!path) {
136 pr_debug("can't get tracing/events/header_event");
137 err = -ENOMEM;
138 goto out;
139 }
140
141 if (stat(path, &st) < 0) {
142 pr_debug("can't read '%s'", path);
143 goto out;
144 }
145
146 if (write(output_fd, "header_event", 13) != 13) {
147 pr_debug("can't write header_event\n");
148 goto out;
149 }
150
151 if (record_file(path, 8) < 0) {
152 pr_debug("can't record header_event file\n");
153 goto out;
154 }
155
156 err = 0;
157 out:
158 put_tracing_file(path);
159 return err;
160 }
161
name_in_tp_list(char * sys,struct tracepoint_path * tps)162 static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
163 {
164 while (tps) {
165 if (!strcmp(sys, tps->name))
166 return true;
167 tps = tps->next;
168 }
169
170 return false;
171 }
172
copy_event_system(const char * sys,struct tracepoint_path * tps)173 static int copy_event_system(const char *sys, struct tracepoint_path *tps)
174 {
175 struct dirent *dent;
176 struct stat st;
177 char *format;
178 DIR *dir;
179 int count = 0;
180 int ret;
181 int err;
182
183 dir = opendir(sys);
184 if (!dir) {
185 pr_debug("can't read directory '%s'", sys);
186 return -errno;
187 }
188
189 while ((dent = readdir(dir))) {
190 if (dent->d_type != DT_DIR ||
191 strcmp(dent->d_name, ".") == 0 ||
192 strcmp(dent->d_name, "..") == 0 ||
193 !name_in_tp_list(dent->d_name, tps))
194 continue;
195 if (asprintf(&format, "%s/%s/format", sys, dent->d_name) < 0) {
196 err = -ENOMEM;
197 goto out;
198 }
199 ret = stat(format, &st);
200 free(format);
201 if (ret < 0)
202 continue;
203 count++;
204 }
205
206 if (write(output_fd, &count, 4) != 4) {
207 err = -EIO;
208 pr_debug("can't write count\n");
209 goto out;
210 }
211
212 rewinddir(dir);
213 while ((dent = readdir(dir))) {
214 if (dent->d_type != DT_DIR ||
215 strcmp(dent->d_name, ".") == 0 ||
216 strcmp(dent->d_name, "..") == 0 ||
217 !name_in_tp_list(dent->d_name, tps))
218 continue;
219 if (asprintf(&format, "%s/%s/format", sys, dent->d_name) < 0) {
220 err = -ENOMEM;
221 goto out;
222 }
223 ret = stat(format, &st);
224
225 if (ret >= 0) {
226 err = record_file(format, 8);
227 if (err) {
228 free(format);
229 goto out;
230 }
231 }
232 free(format);
233 }
234 err = 0;
235 out:
236 closedir(dir);
237 return err;
238 }
239
record_ftrace_files(struct tracepoint_path * tps)240 static int record_ftrace_files(struct tracepoint_path *tps)
241 {
242 char *path;
243 int ret;
244
245 path = get_tracing_file("events/ftrace");
246 if (!path) {
247 pr_debug("can't get tracing/events/ftrace");
248 return -ENOMEM;
249 }
250
251 ret = copy_event_system(path, tps);
252
253 put_tracing_file(path);
254
255 return ret;
256 }
257
system_in_tp_list(char * sys,struct tracepoint_path * tps)258 static bool system_in_tp_list(char *sys, struct tracepoint_path *tps)
259 {
260 while (tps) {
261 if (!strcmp(sys, tps->system))
262 return true;
263 tps = tps->next;
264 }
265
266 return false;
267 }
268
record_event_files(struct tracepoint_path * tps)269 static int record_event_files(struct tracepoint_path *tps)
270 {
271 struct dirent *dent;
272 struct stat st;
273 char *path;
274 char *sys;
275 DIR *dir;
276 int count = 0;
277 int ret;
278 int err;
279
280 path = get_tracing_file("events");
281 if (!path) {
282 pr_debug("can't get tracing/events");
283 return -ENOMEM;
284 }
285
286 dir = opendir(path);
287 if (!dir) {
288 err = -errno;
289 pr_debug("can't read directory '%s'", path);
290 goto out;
291 }
292
293 while ((dent = readdir(dir))) {
294 if (dent->d_type != DT_DIR ||
295 strcmp(dent->d_name, ".") == 0 ||
296 strcmp(dent->d_name, "..") == 0 ||
297 strcmp(dent->d_name, "ftrace") == 0 ||
298 !system_in_tp_list(dent->d_name, tps))
299 continue;
300 count++;
301 }
302
303 if (write(output_fd, &count, 4) != 4) {
304 err = -EIO;
305 pr_debug("can't write count\n");
306 goto out;
307 }
308
309 rewinddir(dir);
310 while ((dent = readdir(dir))) {
311 if (dent->d_type != DT_DIR ||
312 strcmp(dent->d_name, ".") == 0 ||
313 strcmp(dent->d_name, "..") == 0 ||
314 strcmp(dent->d_name, "ftrace") == 0 ||
315 !system_in_tp_list(dent->d_name, tps))
316 continue;
317 if (asprintf(&sys, "%s/%s", path, dent->d_name) < 0) {
318 err = -ENOMEM;
319 goto out;
320 }
321 ret = stat(sys, &st);
322 if (ret >= 0) {
323 ssize_t size = strlen(dent->d_name) + 1;
324
325 if (write(output_fd, dent->d_name, size) != size ||
326 copy_event_system(sys, tps) < 0) {
327 err = -EIO;
328 free(sys);
329 goto out;
330 }
331 }
332 free(sys);
333 }
334 err = 0;
335 out:
336 closedir(dir);
337 put_tracing_file(path);
338
339 return err;
340 }
341
record_proc_kallsyms(void)342 static int record_proc_kallsyms(void)
343 {
344 unsigned long long size = 0;
345 /*
346 * Just to keep older perf.data file parsers happy, record a zero
347 * sized kallsyms file, i.e. do the same thing that was done when
348 * /proc/kallsyms (or something specified via --kallsyms, in a
349 * different path) couldn't be read.
350 */
351 return write(output_fd, &size, 4) != 4 ? -EIO : 0;
352 }
353
record_ftrace_printk(void)354 static int record_ftrace_printk(void)
355 {
356 unsigned int size;
357 char *path;
358 struct stat st;
359 int ret, err = 0;
360
361 path = get_tracing_file("printk_formats");
362 if (!path) {
363 pr_debug("can't get tracing/printk_formats");
364 return -ENOMEM;
365 }
366
367 ret = stat(path, &st);
368 if (ret < 0) {
369 /* not found */
370 size = 0;
371 if (write(output_fd, &size, 4) != 4)
372 err = -EIO;
373 goto out;
374 }
375 err = record_file(path, 4);
376
377 out:
378 put_tracing_file(path);
379 return err;
380 }
381
382 static void
put_tracepoints_path(struct tracepoint_path * tps)383 put_tracepoints_path(struct tracepoint_path *tps)
384 {
385 while (tps) {
386 struct tracepoint_path *t = tps;
387
388 tps = tps->next;
389 zfree(&t->name);
390 zfree(&t->system);
391 free(t);
392 }
393 }
394
395 static struct tracepoint_path *
get_tracepoints_path(struct list_head * pattrs)396 get_tracepoints_path(struct list_head *pattrs)
397 {
398 struct tracepoint_path path, *ppath = &path;
399 struct perf_evsel *pos;
400 int nr_tracepoints = 0;
401
402 list_for_each_entry(pos, pattrs, node) {
403 if (pos->attr.type != PERF_TYPE_TRACEPOINT)
404 continue;
405 ++nr_tracepoints;
406
407 if (pos->name) {
408 ppath->next = tracepoint_name_to_path(pos->name);
409 if (ppath->next)
410 goto next;
411
412 if (strchr(pos->name, ':') == NULL)
413 goto try_id;
414
415 goto error;
416 }
417
418 try_id:
419 ppath->next = tracepoint_id_to_path(pos->attr.config);
420 if (!ppath->next) {
421 error:
422 pr_debug("No memory to alloc tracepoints list\n");
423 put_tracepoints_path(&path);
424 return NULL;
425 }
426 next:
427 ppath = ppath->next;
428 }
429
430 return nr_tracepoints > 0 ? path.next : NULL;
431 }
432
have_tracepoints(struct list_head * pattrs)433 bool have_tracepoints(struct list_head *pattrs)
434 {
435 struct perf_evsel *pos;
436
437 list_for_each_entry(pos, pattrs, node)
438 if (pos->attr.type == PERF_TYPE_TRACEPOINT)
439 return true;
440
441 return false;
442 }
443
tracing_data_header(void)444 static int tracing_data_header(void)
445 {
446 char buf[20];
447 ssize_t size;
448
449 /* just guessing this is someone's birthday.. ;) */
450 buf[0] = 23;
451 buf[1] = 8;
452 buf[2] = 68;
453 memcpy(buf + 3, "tracing", 7);
454
455 if (write(output_fd, buf, 10) != 10)
456 return -1;
457
458 size = strlen(VERSION) + 1;
459 if (write(output_fd, VERSION, size) != size)
460 return -1;
461
462 /* save endian */
463 if (bigendian())
464 buf[0] = 1;
465 else
466 buf[0] = 0;
467
468 if (write(output_fd, buf, 1) != 1)
469 return -1;
470
471 /* save size of long */
472 buf[0] = sizeof(long);
473 if (write(output_fd, buf, 1) != 1)
474 return -1;
475
476 /* save page_size */
477 if (write(output_fd, &page_size, 4) != 4)
478 return -1;
479
480 return 0;
481 }
482
tracing_data_get(struct list_head * pattrs,int fd,bool temp)483 struct tracing_data *tracing_data_get(struct list_head *pattrs,
484 int fd, bool temp)
485 {
486 struct tracepoint_path *tps;
487 struct tracing_data *tdata;
488 int err;
489
490 output_fd = fd;
491
492 tps = get_tracepoints_path(pattrs);
493 if (!tps)
494 return NULL;
495
496 tdata = malloc(sizeof(*tdata));
497 if (!tdata)
498 return NULL;
499
500 tdata->temp = temp;
501 tdata->size = 0;
502
503 if (temp) {
504 int temp_fd;
505
506 snprintf(tdata->temp_file, sizeof(tdata->temp_file),
507 "/tmp/perf-XXXXXX");
508 if (!mkstemp(tdata->temp_file)) {
509 pr_debug("Can't make temp file");
510 free(tdata);
511 return NULL;
512 }
513
514 temp_fd = open(tdata->temp_file, O_RDWR);
515 if (temp_fd < 0) {
516 pr_debug("Can't read '%s'", tdata->temp_file);
517 free(tdata);
518 return NULL;
519 }
520
521 /*
522 * Set the temp file the default output, so all the
523 * tracing data are stored into it.
524 */
525 output_fd = temp_fd;
526 }
527
528 err = tracing_data_header();
529 if (err)
530 goto out;
531 err = record_header_files();
532 if (err)
533 goto out;
534 err = record_ftrace_files(tps);
535 if (err)
536 goto out;
537 err = record_event_files(tps);
538 if (err)
539 goto out;
540 err = record_proc_kallsyms();
541 if (err)
542 goto out;
543 err = record_ftrace_printk();
544
545 out:
546 /*
547 * All tracing data are stored by now, we can restore
548 * the default output file in case we used temp file.
549 */
550 if (temp) {
551 tdata->size = lseek(output_fd, 0, SEEK_CUR);
552 close(output_fd);
553 output_fd = fd;
554 }
555
556 if (err)
557 zfree(&tdata);
558
559 put_tracepoints_path(tps);
560 return tdata;
561 }
562
tracing_data_put(struct tracing_data * tdata)563 int tracing_data_put(struct tracing_data *tdata)
564 {
565 int err = 0;
566
567 if (tdata->temp) {
568 err = record_file(tdata->temp_file, 0);
569 unlink(tdata->temp_file);
570 }
571
572 free(tdata);
573 return err;
574 }
575
read_tracing_data(int fd,struct list_head * pattrs)576 int read_tracing_data(int fd, struct list_head *pattrs)
577 {
578 int err;
579 struct tracing_data *tdata;
580
581 /*
582 * We work over the real file, so we can write data
583 * directly, no temp file is needed.
584 */
585 tdata = tracing_data_get(pattrs, fd, false);
586 if (!tdata)
587 return -ENOMEM;
588
589 err = tracing_data_put(tdata);
590 return err;
591 }
592