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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2008,2009, Steven Rostedt <srostedt@redhat.com>
4 */
5#include <dirent.h>
6#include <mntent.h>
7#include <stdio.h>
8#include <stdlib.h>
9#include <string.h>
10#include <stdarg.h>
11#include <sys/types.h>
12#include <sys/stat.h>
13#include <sys/wait.h>
14#include <fcntl.h>
15#include <unistd.h>
16#include <errno.h>
17#include <stdbool.h>
18#include <linux/list.h>
19#include <linux/kernel.h>
20#include <linux/zalloc.h>
21#include <internal/lib.h> // page_size
22
23#include "trace-event.h"
24#include <api/fs/tracing_path.h>
25#include "evsel.h"
26#include "debug.h"
27
28#define VERSION "0.6"
29
30static int output_fd;
31
32
33int bigendian(void)
34{
35 unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
36 unsigned int *ptr;
37
38 ptr = (unsigned int *)(void *)str;
39 return *ptr == 0x01020304;
40}
41
42/* unfortunately, you can not stat debugfs or proc files for size */
43static int record_file(const char *file, ssize_t hdr_sz)
44{
45 unsigned long long size = 0;
46 char buf[BUFSIZ], *sizep;
47 off_t hdr_pos = lseek(output_fd, 0, SEEK_CUR);
48 int r, fd;
49 int err = -EIO;
50
51 fd = open(file, O_RDONLY);
52 if (fd < 0) {
53 pr_debug("Can't read '%s'", file);
54 return -errno;
55 }
56
57 /* put in zeros for file size, then fill true size later */
58 if (hdr_sz) {
59 if (write(output_fd, &size, hdr_sz) != hdr_sz)
60 goto out;
61 }
62
63 do {
64 r = read(fd, buf, BUFSIZ);
65 if (r > 0) {
66 size += r;
67 if (write(output_fd, buf, r) != r)
68 goto out;
69 }
70 } while (r > 0);
71
72 /* ugh, handle big-endian hdr_size == 4 */
73 sizep = (char*)&size;
74 if (bigendian())
75 sizep += sizeof(u64) - hdr_sz;
76
77 if (hdr_sz && pwrite(output_fd, sizep, hdr_sz, hdr_pos) < 0) {
78 pr_debug("writing file size failed\n");
79 goto out;
80 }
81
82 err = 0;
83out:
84 close(fd);
85 return err;
86}
87
88static int record_header_files(void)
89{
90 char *path = get_events_file("header_page");
91 struct stat st;
92 int err = -EIO;
93
94 if (!path) {
95 pr_debug("can't get tracing/events/header_page");
96 return -ENOMEM;
97 }
98
99 if (stat(path, &st) < 0) {
100 pr_debug("can't read '%s'", path);
101 goto out;
102 }
103
104 if (write(output_fd, "header_page", 12) != 12) {
105 pr_debug("can't write header_page\n");
106 goto out;
107 }
108
109 if (record_file(path, 8) < 0) {
110 pr_debug("can't record header_page file\n");
111 goto out;
112 }
113
114 put_events_file(path);
115
116 path = get_events_file("header_event");
117 if (!path) {
118 pr_debug("can't get tracing/events/header_event");
119 err = -ENOMEM;
120 goto out;
121 }
122
123 if (stat(path, &st) < 0) {
124 pr_debug("can't read '%s'", path);
125 goto out;
126 }
127
128 if (write(output_fd, "header_event", 13) != 13) {
129 pr_debug("can't write header_event\n");
130 goto out;
131 }
132
133 if (record_file(path, 8) < 0) {
134 pr_debug("can't record header_event file\n");
135 goto out;
136 }
137
138 err = 0;
139out:
140 put_events_file(path);
141 return err;
142}
143
144static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
145{
146 while (tps) {
147 if (!strcmp(sys, tps->name))
148 return true;
149 tps = tps->next;
150 }
151
152 return false;
153}
154
155#define for_each_event(dir, dent, tps) \
156 while ((dent = readdir(dir))) \
157 if (dent->d_type == DT_DIR && \
158 (strcmp(dent->d_name, ".")) && \
159 (strcmp(dent->d_name, ".."))) \
160
161static int copy_event_system(const char *sys, struct tracepoint_path *tps)
162{
163 struct dirent *dent;
164 struct stat st;
165 char *format;
166 DIR *dir;
167 int count = 0;
168 int ret;
169 int err;
170
171 dir = opendir(sys);
172 if (!dir) {
173 pr_debug("can't read directory '%s'", sys);
174 return -errno;
175 }
176
177 for_each_event(dir, dent, tps) {
178 if (!name_in_tp_list(dent->d_name, tps))
179 continue;
180
181 if (asprintf(&format, "%s/%s/format", sys, dent->d_name) < 0) {
182 err = -ENOMEM;
183 goto out;
184 }
185 ret = stat(format, &st);
186 free(format);
187 if (ret < 0)
188 continue;
189 count++;
190 }
191
192 if (write(output_fd, &count, 4) != 4) {
193 err = -EIO;
194 pr_debug("can't write count\n");
195 goto out;
196 }
197
198 rewinddir(dir);
199 for_each_event(dir, dent, tps) {
200 if (!name_in_tp_list(dent->d_name, tps))
201 continue;
202
203 if (asprintf(&format, "%s/%s/format", sys, dent->d_name) < 0) {
204 err = -ENOMEM;
205 goto out;
206 }
207 ret = stat(format, &st);
208
209 if (ret >= 0) {
210 err = record_file(format, 8);
211 if (err) {
212 free(format);
213 goto out;
214 }
215 }
216 free(format);
217 }
218 err = 0;
219out:
220 closedir(dir);
221 return err;
222}
223
224static int record_ftrace_files(struct tracepoint_path *tps)
225{
226 char *path;
227 int ret;
228
229 path = get_events_file("ftrace");
230 if (!path) {
231 pr_debug("can't get tracing/events/ftrace");
232 return -ENOMEM;
233 }
234
235 ret = copy_event_system(path, tps);
236
237 put_tracing_file(path);
238
239 return ret;
240}
241
242static bool system_in_tp_list(char *sys, struct tracepoint_path *tps)
243{
244 while (tps) {
245 if (!strcmp(sys, tps->system))
246 return true;
247 tps = tps->next;
248 }
249
250 return false;
251}
252
253static int record_event_files(struct tracepoint_path *tps)
254{
255 struct dirent *dent;
256 struct stat st;
257 char *path;
258 char *sys;
259 DIR *dir;
260 int count = 0;
261 int ret;
262 int err;
263
264 path = get_tracing_file("events");
265 if (!path) {
266 pr_debug("can't get tracing/events");
267 return -ENOMEM;
268 }
269
270 dir = opendir(path);
271 if (!dir) {
272 err = -errno;
273 pr_debug("can't read directory '%s'", path);
274 goto out;
275 }
276
277 for_each_event(dir, dent, tps) {
278 if (strcmp(dent->d_name, "ftrace") == 0 ||
279 !system_in_tp_list(dent->d_name, tps))
280 continue;
281
282 count++;
283 }
284
285 if (write(output_fd, &count, 4) != 4) {
286 err = -EIO;
287 pr_debug("can't write count\n");
288 goto out;
289 }
290
291 rewinddir(dir);
292 for_each_event(dir, dent, tps) {
293 if (strcmp(dent->d_name, "ftrace") == 0 ||
294 !system_in_tp_list(dent->d_name, tps))
295 continue;
296
297 if (asprintf(&sys, "%s/%s", path, dent->d_name) < 0) {
298 err = -ENOMEM;
299 goto out;
300 }
301 ret = stat(sys, &st);
302 if (ret >= 0) {
303 ssize_t size = strlen(dent->d_name) + 1;
304
305 if (write(output_fd, dent->d_name, size) != size ||
306 copy_event_system(sys, tps) < 0) {
307 err = -EIO;
308 free(sys);
309 goto out;
310 }
311 }
312 free(sys);
313 }
314 err = 0;
315out:
316 closedir(dir);
317 put_tracing_file(path);
318
319 return err;
320}
321
322static int record_proc_kallsyms(void)
323{
324 unsigned long long size = 0;
325 /*
326 * Just to keep older perf.data file parsers happy, record a zero
327 * sized kallsyms file, i.e. do the same thing that was done when
328 * /proc/kallsyms (or something specified via --kallsyms, in a
329 * different path) couldn't be read.
330 */
331 return write(output_fd, &size, 4) != 4 ? -EIO : 0;
332}
333
334static int record_ftrace_printk(void)
335{
336 unsigned int size;
337 char *path;
338 struct stat st;
339 int ret, err = 0;
340
341 path = get_tracing_file("printk_formats");
342 if (!path) {
343 pr_debug("can't get tracing/printk_formats");
344 return -ENOMEM;
345 }
346
347 ret = stat(path, &st);
348 if (ret < 0) {
349 /* not found */
350 size = 0;
351 if (write(output_fd, &size, 4) != 4)
352 err = -EIO;
353 goto out;
354 }
355 err = record_file(path, 4);
356
357out:
358 put_tracing_file(path);
359 return err;
360}
361
362static int record_saved_cmdline(void)
363{
364 unsigned long long size;
365 char *path;
366 struct stat st;
367 int ret, err = 0;
368
369 path = get_tracing_file("saved_cmdlines");
370 if (!path) {
371 pr_debug("can't get tracing/saved_cmdline");
372 return -ENOMEM;
373 }
374
375 ret = stat(path, &st);
376 if (ret < 0) {
377 /* not found */
378 size = 0;
379 if (write(output_fd, &size, 8) != 8)
380 err = -EIO;
381 goto out;
382 }
383 err = record_file(path, 8);
384
385out:
386 put_tracing_file(path);
387 return err;
388}
389
390static void
391put_tracepoints_path(struct tracepoint_path *tps)
392{
393 while (tps) {
394 struct tracepoint_path *t = tps;
395
396 tps = tps->next;
397 zfree(&t->name);
398 zfree(&t->system);
399 free(t);
400 }
401}
402
403static struct tracepoint_path *
404get_tracepoints_path(struct list_head *pattrs)
405{
406 struct tracepoint_path path, *ppath = &path;
407 struct evsel *pos;
408 int nr_tracepoints = 0;
409
410 list_for_each_entry(pos, pattrs, core.node) {
411 if (pos->core.attr.type != PERF_TYPE_TRACEPOINT)
412 continue;
413 ++nr_tracepoints;
414
415 if (pos->name) {
416 ppath->next = tracepoint_name_to_path(pos->name);
417 if (ppath->next)
418 goto next;
419
420 if (strchr(pos->name, ':') == NULL)
421 goto try_id;
422
423 goto error;
424 }
425
426try_id:
427 ppath->next = tracepoint_id_to_path(pos->core.attr.config);
428 if (!ppath->next) {
429error:
430 pr_debug("No memory to alloc tracepoints list\n");
431 put_tracepoints_path(&path);
432 return NULL;
433 }
434next:
435 ppath = ppath->next;
436 }
437
438 return nr_tracepoints > 0 ? path.next : NULL;
439}
440
441bool have_tracepoints(struct list_head *pattrs)
442{
443 struct evsel *pos;
444
445 list_for_each_entry(pos, pattrs, core.node)
446 if (pos->core.attr.type == PERF_TYPE_TRACEPOINT)
447 return true;
448
449 return false;
450}
451
452static int tracing_data_header(void)
453{
454 char buf[20];
455 ssize_t size;
456
457 /* just guessing this is someone's birthday.. ;) */
458 buf[0] = 23;
459 buf[1] = 8;
460 buf[2] = 68;
461 memcpy(buf + 3, "tracing", 7);
462
463 if (write(output_fd, buf, 10) != 10)
464 return -1;
465
466 size = strlen(VERSION) + 1;
467 if (write(output_fd, VERSION, size) != size)
468 return -1;
469
470 /* save endian */
471 if (bigendian())
472 buf[0] = 1;
473 else
474 buf[0] = 0;
475
476 if (write(output_fd, buf, 1) != 1)
477 return -1;
478
479 /* save size of long */
480 buf[0] = sizeof(long);
481 if (write(output_fd, buf, 1) != 1)
482 return -1;
483
484 /* save page_size */
485 if (write(output_fd, &page_size, 4) != 4)
486 return -1;
487
488 return 0;
489}
490
491struct tracing_data *tracing_data_get(struct list_head *pattrs,
492 int fd, bool temp)
493{
494 struct tracepoint_path *tps;
495 struct tracing_data *tdata;
496 int err;
497
498 output_fd = fd;
499
500 tps = get_tracepoints_path(pattrs);
501 if (!tps)
502 return NULL;
503
504 tdata = malloc(sizeof(*tdata));
505 if (!tdata)
506 return NULL;
507
508 tdata->temp = temp;
509 tdata->size = 0;
510
511 if (temp) {
512 int temp_fd;
513
514 snprintf(tdata->temp_file, sizeof(tdata->temp_file),
515 "/tmp/perf-XXXXXX");
516 if (!mkstemp(tdata->temp_file)) {
517 pr_debug("Can't make temp file");
518 free(tdata);
519 return NULL;
520 }
521
522 temp_fd = open(tdata->temp_file, O_RDWR);
523 if (temp_fd < 0) {
524 pr_debug("Can't read '%s'", tdata->temp_file);
525 free(tdata);
526 return NULL;
527 }
528
529 /*
530 * Set the temp file the default output, so all the
531 * tracing data are stored into it.
532 */
533 output_fd = temp_fd;
534 }
535
536 err = tracing_data_header();
537 if (err)
538 goto out;
539 err = record_header_files();
540 if (err)
541 goto out;
542 err = record_ftrace_files(tps);
543 if (err)
544 goto out;
545 err = record_event_files(tps);
546 if (err)
547 goto out;
548 err = record_proc_kallsyms();
549 if (err)
550 goto out;
551 err = record_ftrace_printk();
552 if (err)
553 goto out;
554 err = record_saved_cmdline();
555
556out:
557 /*
558 * All tracing data are stored by now, we can restore
559 * the default output file in case we used temp file.
560 */
561 if (temp) {
562 tdata->size = lseek(output_fd, 0, SEEK_CUR);
563 close(output_fd);
564 output_fd = fd;
565 }
566
567 if (err)
568 zfree(&tdata);
569
570 put_tracepoints_path(tps);
571 return tdata;
572}
573
574int tracing_data_put(struct tracing_data *tdata)
575{
576 int err = 0;
577
578 if (tdata->temp) {
579 err = record_file(tdata->temp_file, 0);
580 unlink(tdata->temp_file);
581 }
582
583 free(tdata);
584 return err;
585}
586
587int read_tracing_data(int fd, struct list_head *pattrs)
588{
589 int err;
590 struct tracing_data *tdata;
591
592 /*
593 * We work over the real file, so we can write data
594 * directly, no temp file is needed.
595 */
596 tdata = tracing_data_get(pattrs, fd, false);
597 if (!tdata)
598 return -ENOMEM;
599
600 err = tracing_data_put(tdata);
601 return err;
602}
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
47static int output_fd;
48
49
50int 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 */
60static 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;
100out:
101 close(fd);
102 return err;
103}
104
105static 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;
157out:
158 put_tracing_file(path);
159 return err;
160}
161
162static 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
173static 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;
235out:
236 closedir(dir);
237 return err;
238}
239
240static 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
258static 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
269static 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;
335out:
336 closedir(dir);
337 put_tracing_file(path);
338
339 return err;
340}
341
342static 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
354static 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
377out:
378 put_tracing_file(path);
379 return err;
380}
381
382static void
383put_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
395static struct tracepoint_path *
396get_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
418try_id:
419 ppath->next = tracepoint_id_to_path(pos->attr.config);
420 if (!ppath->next) {
421error:
422 pr_debug("No memory to alloc tracepoints list\n");
423 put_tracepoints_path(&path);
424 return NULL;
425 }
426next:
427 ppath = ppath->next;
428 }
429
430 return nr_tracepoints > 0 ? path.next : NULL;
431}
432
433bool 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
444static 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
483struct 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 return NULL;
511 }
512
513 temp_fd = open(tdata->temp_file, O_RDWR);
514 if (temp_fd < 0) {
515 pr_debug("Can't read '%s'", tdata->temp_file);
516 return NULL;
517 }
518
519 /*
520 * Set the temp file the default output, so all the
521 * tracing data are stored into it.
522 */
523 output_fd = temp_fd;
524 }
525
526 err = tracing_data_header();
527 if (err)
528 goto out;
529 err = record_header_files();
530 if (err)
531 goto out;
532 err = record_ftrace_files(tps);
533 if (err)
534 goto out;
535 err = record_event_files(tps);
536 if (err)
537 goto out;
538 err = record_proc_kallsyms();
539 if (err)
540 goto out;
541 err = record_ftrace_printk();
542
543out:
544 /*
545 * All tracing data are stored by now, we can restore
546 * the default output file in case we used temp file.
547 */
548 if (temp) {
549 tdata->size = lseek(output_fd, 0, SEEK_CUR);
550 close(output_fd);
551 output_fd = fd;
552 }
553
554 if (err)
555 zfree(&tdata);
556
557 put_tracepoints_path(tps);
558 return tdata;
559}
560
561int tracing_data_put(struct tracing_data *tdata)
562{
563 int err = 0;
564
565 if (tdata->temp) {
566 err = record_file(tdata->temp_file, 0);
567 unlink(tdata->temp_file);
568 }
569
570 free(tdata);
571 return err;
572}
573
574int read_tracing_data(int fd, struct list_head *pattrs)
575{
576 int err;
577 struct tracing_data *tdata;
578
579 /*
580 * We work over the real file, so we can write data
581 * directly, no temp file is needed.
582 */
583 tdata = tracing_data_get(pattrs, fd, false);
584 if (!tdata)
585 return -ENOMEM;
586
587 err = tracing_data_put(tdata);
588 return err;
589}