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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 "debugfs.h"
42#include "evsel.h"
43
44#define VERSION "0.5"
45
46#define TRACE_CTRL "tracing_on"
47#define TRACE "trace"
48#define AVAILABLE "available_tracers"
49#define CURRENT "current_tracer"
50#define ITER_CTRL "trace_options"
51#define MAX_LATENCY "tracing_max_latency"
52
53unsigned int page_size;
54
55static const char *output_file = "trace.info";
56static int output_fd;
57
58struct event_list {
59 struct event_list *next;
60 const char *event;
61};
62
63struct events {
64 struct events *sibling;
65 struct events *children;
66 struct events *next;
67 char *name;
68};
69
70
71static void *malloc_or_die(unsigned int size)
72{
73 void *data;
74
75 data = malloc(size);
76 if (!data)
77 die("malloc");
78 return data;
79}
80
81static const char *find_debugfs(void)
82{
83 const char *path = debugfs_mount(NULL);
84
85 if (!path)
86 die("Your kernel not support debugfs filesystem");
87
88 return path;
89}
90
91/*
92 * Finds the path to the debugfs/tracing
93 * Allocates the string and stores it.
94 */
95static const char *find_tracing_dir(void)
96{
97 static char *tracing;
98 static int tracing_found;
99 const char *debugfs;
100
101 if (tracing_found)
102 return tracing;
103
104 debugfs = find_debugfs();
105
106 tracing = malloc_or_die(strlen(debugfs) + 9);
107
108 sprintf(tracing, "%s/tracing", debugfs);
109
110 tracing_found = 1;
111 return tracing;
112}
113
114static char *get_tracing_file(const char *name)
115{
116 const char *tracing;
117 char *file;
118
119 tracing = find_tracing_dir();
120 if (!tracing)
121 return NULL;
122
123 file = malloc_or_die(strlen(tracing) + strlen(name) + 2);
124
125 sprintf(file, "%s/%s", tracing, name);
126 return file;
127}
128
129static void put_tracing_file(char *file)
130{
131 free(file);
132}
133
134static ssize_t calc_data_size;
135
136static ssize_t write_or_die(const void *buf, size_t len)
137{
138 int ret;
139
140 if (calc_data_size) {
141 calc_data_size += len;
142 return len;
143 }
144
145 ret = write(output_fd, buf, len);
146 if (ret < 0)
147 die("writing to '%s'", output_file);
148
149 return ret;
150}
151
152int bigendian(void)
153{
154 unsigned char str[] = { 0x1, 0x2, 0x3, 0x4, 0x0, 0x0, 0x0, 0x0};
155 unsigned int *ptr;
156
157 ptr = (unsigned int *)(void *)str;
158 return *ptr == 0x01020304;
159}
160
161/* unfortunately, you can not stat debugfs or proc files for size */
162static void record_file(const char *file, size_t hdr_sz)
163{
164 unsigned long long size = 0;
165 char buf[BUFSIZ], *sizep;
166 off_t hdr_pos = lseek(output_fd, 0, SEEK_CUR);
167 int r, fd;
168
169 fd = open(file, O_RDONLY);
170 if (fd < 0)
171 die("Can't read '%s'", file);
172
173 /* put in zeros for file size, then fill true size later */
174 if (hdr_sz)
175 write_or_die(&size, hdr_sz);
176
177 do {
178 r = read(fd, buf, BUFSIZ);
179 if (r > 0) {
180 size += r;
181 write_or_die(buf, r);
182 }
183 } while (r > 0);
184 close(fd);
185
186 /* ugh, handle big-endian hdr_size == 4 */
187 sizep = (char*)&size;
188 if (bigendian())
189 sizep += sizeof(u64) - hdr_sz;
190
191 if (hdr_sz && pwrite(output_fd, sizep, hdr_sz, hdr_pos) < 0)
192 die("writing to %s", output_file);
193}
194
195static void read_header_files(void)
196{
197 char *path;
198 struct stat st;
199
200 path = get_tracing_file("events/header_page");
201 if (stat(path, &st) < 0)
202 die("can't read '%s'", path);
203
204 write_or_die("header_page", 12);
205 record_file(path, 8);
206 put_tracing_file(path);
207
208 path = get_tracing_file("events/header_event");
209 if (stat(path, &st) < 0)
210 die("can't read '%s'", path);
211
212 write_or_die("header_event", 13);
213 record_file(path, 8);
214 put_tracing_file(path);
215}
216
217static bool name_in_tp_list(char *sys, struct tracepoint_path *tps)
218{
219 while (tps) {
220 if (!strcmp(sys, tps->name))
221 return true;
222 tps = tps->next;
223 }
224
225 return false;
226}
227
228static void copy_event_system(const char *sys, struct tracepoint_path *tps)
229{
230 struct dirent *dent;
231 struct stat st;
232 char *format;
233 DIR *dir;
234 int count = 0;
235 int ret;
236
237 dir = opendir(sys);
238 if (!dir)
239 die("can't read directory '%s'", sys);
240
241 while ((dent = readdir(dir))) {
242 if (dent->d_type != DT_DIR ||
243 strcmp(dent->d_name, ".") == 0 ||
244 strcmp(dent->d_name, "..") == 0 ||
245 !name_in_tp_list(dent->d_name, tps))
246 continue;
247 format = malloc_or_die(strlen(sys) + strlen(dent->d_name) + 10);
248 sprintf(format, "%s/%s/format", sys, dent->d_name);
249 ret = stat(format, &st);
250 free(format);
251 if (ret < 0)
252 continue;
253 count++;
254 }
255
256 write_or_die(&count, 4);
257
258 rewinddir(dir);
259 while ((dent = readdir(dir))) {
260 if (dent->d_type != DT_DIR ||
261 strcmp(dent->d_name, ".") == 0 ||
262 strcmp(dent->d_name, "..") == 0 ||
263 !name_in_tp_list(dent->d_name, tps))
264 continue;
265 format = malloc_or_die(strlen(sys) + strlen(dent->d_name) + 10);
266 sprintf(format, "%s/%s/format", sys, dent->d_name);
267 ret = stat(format, &st);
268
269 if (ret >= 0)
270 record_file(format, 8);
271
272 free(format);
273 }
274 closedir(dir);
275}
276
277static void read_ftrace_files(struct tracepoint_path *tps)
278{
279 char *path;
280
281 path = get_tracing_file("events/ftrace");
282
283 copy_event_system(path, tps);
284
285 put_tracing_file(path);
286}
287
288static bool system_in_tp_list(char *sys, struct tracepoint_path *tps)
289{
290 while (tps) {
291 if (!strcmp(sys, tps->system))
292 return true;
293 tps = tps->next;
294 }
295
296 return false;
297}
298
299static void read_event_files(struct tracepoint_path *tps)
300{
301 struct dirent *dent;
302 struct stat st;
303 char *path;
304 char *sys;
305 DIR *dir;
306 int count = 0;
307 int ret;
308
309 path = get_tracing_file("events");
310
311 dir = opendir(path);
312 if (!dir)
313 die("can't read directory '%s'", path);
314
315 while ((dent = readdir(dir))) {
316 if (dent->d_type != DT_DIR ||
317 strcmp(dent->d_name, ".") == 0 ||
318 strcmp(dent->d_name, "..") == 0 ||
319 strcmp(dent->d_name, "ftrace") == 0 ||
320 !system_in_tp_list(dent->d_name, tps))
321 continue;
322 count++;
323 }
324
325 write_or_die(&count, 4);
326
327 rewinddir(dir);
328 while ((dent = readdir(dir))) {
329 if (dent->d_type != DT_DIR ||
330 strcmp(dent->d_name, ".") == 0 ||
331 strcmp(dent->d_name, "..") == 0 ||
332 strcmp(dent->d_name, "ftrace") == 0 ||
333 !system_in_tp_list(dent->d_name, tps))
334 continue;
335 sys = malloc_or_die(strlen(path) + strlen(dent->d_name) + 2);
336 sprintf(sys, "%s/%s", path, dent->d_name);
337 ret = stat(sys, &st);
338 if (ret >= 0) {
339 write_or_die(dent->d_name, strlen(dent->d_name) + 1);
340 copy_event_system(sys, tps);
341 }
342 free(sys);
343 }
344
345 closedir(dir);
346 put_tracing_file(path);
347}
348
349static void read_proc_kallsyms(void)
350{
351 unsigned int size;
352 const char *path = "/proc/kallsyms";
353 struct stat st;
354 int ret;
355
356 ret = stat(path, &st);
357 if (ret < 0) {
358 /* not found */
359 size = 0;
360 write_or_die(&size, 4);
361 return;
362 }
363 record_file(path, 4);
364}
365
366static void read_ftrace_printk(void)
367{
368 unsigned int size;
369 char *path;
370 struct stat st;
371 int ret;
372
373 path = get_tracing_file("printk_formats");
374 ret = stat(path, &st);
375 if (ret < 0) {
376 /* not found */
377 size = 0;
378 write_or_die(&size, 4);
379 goto out;
380 }
381 record_file(path, 4);
382
383out:
384 put_tracing_file(path);
385}
386
387static struct tracepoint_path *
388get_tracepoints_path(struct list_head *pattrs)
389{
390 struct tracepoint_path path, *ppath = &path;
391 struct perf_evsel *pos;
392 int nr_tracepoints = 0;
393
394 list_for_each_entry(pos, pattrs, node) {
395 if (pos->attr.type != PERF_TYPE_TRACEPOINT)
396 continue;
397 ++nr_tracepoints;
398 ppath->next = tracepoint_id_to_path(pos->attr.config);
399 if (!ppath->next)
400 die("%s\n", "No memory to alloc tracepoints list");
401 ppath = ppath->next;
402 }
403
404 return nr_tracepoints > 0 ? path.next : NULL;
405}
406
407static void
408put_tracepoints_path(struct tracepoint_path *tps)
409{
410 while (tps) {
411 struct tracepoint_path *t = tps;
412
413 tps = tps->next;
414 free(t->name);
415 free(t->system);
416 free(t);
417 }
418}
419
420bool have_tracepoints(struct list_head *pattrs)
421{
422 struct perf_evsel *pos;
423
424 list_for_each_entry(pos, pattrs, node)
425 if (pos->attr.type == PERF_TYPE_TRACEPOINT)
426 return true;
427
428 return false;
429}
430
431static void tracing_data_header(void)
432{
433 char buf[20];
434
435 /* just guessing this is someone's birthday.. ;) */
436 buf[0] = 23;
437 buf[1] = 8;
438 buf[2] = 68;
439 memcpy(buf + 3, "tracing", 7);
440
441 write_or_die(buf, 10);
442
443 write_or_die(VERSION, strlen(VERSION) + 1);
444
445 /* save endian */
446 if (bigendian())
447 buf[0] = 1;
448 else
449 buf[0] = 0;
450
451 read_trace_init(buf[0], buf[0]);
452
453 write_or_die(buf, 1);
454
455 /* save size of long */
456 buf[0] = sizeof(long);
457 write_or_die(buf, 1);
458
459 /* save page_size */
460 page_size = sysconf(_SC_PAGESIZE);
461 write_or_die(&page_size, 4);
462}
463
464struct tracing_data *tracing_data_get(struct list_head *pattrs,
465 int fd, bool temp)
466{
467 struct tracepoint_path *tps;
468 struct tracing_data *tdata;
469
470 output_fd = fd;
471
472 tps = get_tracepoints_path(pattrs);
473 if (!tps)
474 return NULL;
475
476 tdata = malloc_or_die(sizeof(*tdata));
477 tdata->temp = temp;
478 tdata->size = 0;
479
480 if (temp) {
481 int temp_fd;
482
483 snprintf(tdata->temp_file, sizeof(tdata->temp_file),
484 "/tmp/perf-XXXXXX");
485 if (!mkstemp(tdata->temp_file))
486 die("Can't make temp file");
487
488 temp_fd = open(tdata->temp_file, O_RDWR);
489 if (temp_fd < 0)
490 die("Can't read '%s'", tdata->temp_file);
491
492 /*
493 * Set the temp file the default output, so all the
494 * tracing data are stored into it.
495 */
496 output_fd = temp_fd;
497 }
498
499 tracing_data_header();
500 read_header_files();
501 read_ftrace_files(tps);
502 read_event_files(tps);
503 read_proc_kallsyms();
504 read_ftrace_printk();
505
506 /*
507 * All tracing data are stored by now, we can restore
508 * the default output file in case we used temp file.
509 */
510 if (temp) {
511 tdata->size = lseek(output_fd, 0, SEEK_CUR);
512 close(output_fd);
513 output_fd = fd;
514 }
515
516 put_tracepoints_path(tps);
517 return tdata;
518}
519
520void tracing_data_put(struct tracing_data *tdata)
521{
522 if (tdata->temp) {
523 record_file(tdata->temp_file, 0);
524 unlink(tdata->temp_file);
525 }
526
527 free(tdata);
528}
529
530int read_tracing_data(int fd, struct list_head *pattrs)
531{
532 struct tracing_data *tdata;
533
534 /*
535 * We work over the real file, so we can write data
536 * directly, no temp file is needed.
537 */
538 tdata = tracing_data_get(pattrs, fd, false);
539 if (!tdata)
540 return -ENOMEM;
541
542 tracing_data_put(tdata);
543 return 0;
544}