Commit | Line | Data |
---|---|---|
b77e38aa SR |
1 | /* |
2 | * event tracer | |
3 | * | |
4 | * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com> | |
5 | * | |
981d081e SR |
6 | * - Added format output of fields of the trace point. |
7 | * This was based off of work by Tom Zanussi <tzanussi@gmail.com>. | |
8 | * | |
b77e38aa SR |
9 | */ |
10 | ||
11 | #include <linux/debugfs.h> | |
12 | #include <linux/uaccess.h> | |
13 | #include <linux/module.h> | |
14 | #include <linux/ctype.h> | |
15 | ||
91729ef9 | 16 | #include "trace_output.h" |
b77e38aa | 17 | |
b628b3e6 SR |
18 | #define TRACE_SYSTEM "TRACE_SYSTEM" |
19 | ||
11a241a3 SR |
20 | static DEFINE_MUTEX(event_mutex); |
21 | ||
cf027f64 TZ |
22 | int trace_define_field(struct ftrace_event_call *call, char *type, |
23 | char *name, int offset, int size) | |
24 | { | |
25 | struct ftrace_event_field *field; | |
26 | ||
fe9f57f2 | 27 | field = kzalloc(sizeof(*field), GFP_KERNEL); |
cf027f64 TZ |
28 | if (!field) |
29 | goto err; | |
fe9f57f2 | 30 | |
cf027f64 TZ |
31 | field->name = kstrdup(name, GFP_KERNEL); |
32 | if (!field->name) | |
33 | goto err; | |
fe9f57f2 | 34 | |
cf027f64 TZ |
35 | field->type = kstrdup(type, GFP_KERNEL); |
36 | if (!field->type) | |
37 | goto err; | |
fe9f57f2 | 38 | |
cf027f64 TZ |
39 | field->offset = offset; |
40 | field->size = size; | |
41 | list_add(&field->link, &call->fields); | |
42 | ||
43 | return 0; | |
fe9f57f2 | 44 | |
cf027f64 TZ |
45 | err: |
46 | if (field) { | |
47 | kfree(field->name); | |
48 | kfree(field->type); | |
49 | } | |
50 | kfree(field); | |
fe9f57f2 | 51 | |
cf027f64 TZ |
52 | return -ENOMEM; |
53 | } | |
54 | ||
b77e38aa SR |
55 | static void ftrace_clear_events(void) |
56 | { | |
57 | struct ftrace_event_call *call = (void *)__start_ftrace_events; | |
58 | ||
59 | ||
60 | while ((unsigned long)call < (unsigned long)__stop_ftrace_events) { | |
61 | ||
62 | if (call->enabled) { | |
63 | call->enabled = 0; | |
64 | call->unregfunc(); | |
65 | } | |
66 | call++; | |
67 | } | |
68 | } | |
69 | ||
fd994989 SR |
70 | static void ftrace_event_enable_disable(struct ftrace_event_call *call, |
71 | int enable) | |
72 | { | |
73 | ||
74 | switch (enable) { | |
75 | case 0: | |
76 | if (call->enabled) { | |
77 | call->enabled = 0; | |
78 | call->unregfunc(); | |
79 | } | |
fd994989 SR |
80 | break; |
81 | case 1: | |
da4d0302 | 82 | if (!call->enabled) { |
fd994989 SR |
83 | call->enabled = 1; |
84 | call->regfunc(); | |
85 | } | |
fd994989 SR |
86 | break; |
87 | } | |
88 | } | |
89 | ||
b77e38aa SR |
90 | static int ftrace_set_clr_event(char *buf, int set) |
91 | { | |
1473e441 | 92 | struct ftrace_event_call *call = __start_ftrace_events; |
b628b3e6 SR |
93 | char *event = NULL, *sub = NULL, *match; |
94 | int ret = -EINVAL; | |
95 | ||
96 | /* | |
97 | * The buf format can be <subsystem>:<event-name> | |
98 | * *:<event-name> means any event by that name. | |
99 | * :<event-name> is the same. | |
100 | * | |
101 | * <subsystem>:* means all events in that subsystem | |
102 | * <subsystem>: means the same. | |
103 | * | |
104 | * <name> (no ':') means all events in a subsystem with | |
105 | * the name <name> or any event that matches <name> | |
106 | */ | |
107 | ||
108 | match = strsep(&buf, ":"); | |
109 | if (buf) { | |
110 | sub = match; | |
111 | event = buf; | |
112 | match = NULL; | |
113 | ||
114 | if (!strlen(sub) || strcmp(sub, "*") == 0) | |
115 | sub = NULL; | |
116 | if (!strlen(event) || strcmp(event, "*") == 0) | |
117 | event = NULL; | |
118 | } | |
b77e38aa | 119 | |
11a241a3 | 120 | mutex_lock(&event_mutex); |
ac199db0 | 121 | for_each_event(call) { |
b77e38aa | 122 | |
40e26815 | 123 | if (!call->name || !call->regfunc) |
1473e441 SR |
124 | continue; |
125 | ||
b628b3e6 SR |
126 | if (match && |
127 | strcmp(match, call->name) != 0 && | |
128 | strcmp(match, call->system) != 0) | |
129 | continue; | |
130 | ||
131 | if (sub && strcmp(sub, call->system) != 0) | |
132 | continue; | |
133 | ||
134 | if (event && strcmp(event, call->name) != 0) | |
b77e38aa | 135 | continue; |
b77e38aa | 136 | |
fd994989 SR |
137 | ftrace_event_enable_disable(call, set); |
138 | ||
b628b3e6 | 139 | ret = 0; |
b77e38aa | 140 | } |
11a241a3 SR |
141 | mutex_unlock(&event_mutex); |
142 | ||
b628b3e6 | 143 | return ret; |
b77e38aa SR |
144 | } |
145 | ||
146 | /* 128 should be much more than enough */ | |
147 | #define EVENT_BUF_SIZE 127 | |
148 | ||
149 | static ssize_t | |
150 | ftrace_event_write(struct file *file, const char __user *ubuf, | |
151 | size_t cnt, loff_t *ppos) | |
152 | { | |
153 | size_t read = 0; | |
154 | int i, set = 1; | |
155 | ssize_t ret; | |
156 | char *buf; | |
157 | char ch; | |
158 | ||
159 | if (!cnt || cnt < 0) | |
160 | return 0; | |
161 | ||
1852fcce SR |
162 | ret = tracing_update_buffers(); |
163 | if (ret < 0) | |
164 | return ret; | |
165 | ||
b77e38aa SR |
166 | ret = get_user(ch, ubuf++); |
167 | if (ret) | |
168 | return ret; | |
169 | read++; | |
170 | cnt--; | |
171 | ||
172 | /* skip white space */ | |
173 | while (cnt && isspace(ch)) { | |
174 | ret = get_user(ch, ubuf++); | |
175 | if (ret) | |
176 | return ret; | |
177 | read++; | |
178 | cnt--; | |
179 | } | |
180 | ||
181 | /* Only white space found? */ | |
182 | if (isspace(ch)) { | |
183 | file->f_pos += read; | |
184 | ret = read; | |
185 | return ret; | |
186 | } | |
187 | ||
188 | buf = kmalloc(EVENT_BUF_SIZE+1, GFP_KERNEL); | |
189 | if (!buf) | |
190 | return -ENOMEM; | |
191 | ||
192 | if (cnt > EVENT_BUF_SIZE) | |
193 | cnt = EVENT_BUF_SIZE; | |
194 | ||
195 | i = 0; | |
196 | while (cnt && !isspace(ch)) { | |
197 | if (!i && ch == '!') | |
198 | set = 0; | |
199 | else | |
200 | buf[i++] = ch; | |
201 | ||
202 | ret = get_user(ch, ubuf++); | |
203 | if (ret) | |
204 | goto out_free; | |
205 | read++; | |
206 | cnt--; | |
207 | } | |
208 | buf[i] = 0; | |
209 | ||
210 | file->f_pos += read; | |
211 | ||
212 | ret = ftrace_set_clr_event(buf, set); | |
213 | if (ret) | |
214 | goto out_free; | |
215 | ||
216 | ret = read; | |
217 | ||
218 | out_free: | |
219 | kfree(buf); | |
220 | ||
221 | return ret; | |
222 | } | |
223 | ||
224 | static void * | |
225 | t_next(struct seq_file *m, void *v, loff_t *pos) | |
226 | { | |
227 | struct ftrace_event_call *call = m->private; | |
228 | struct ftrace_event_call *next = call; | |
229 | ||
230 | (*pos)++; | |
231 | ||
40e26815 SR |
232 | for (;;) { |
233 | if ((unsigned long)call >= (unsigned long)__stop_ftrace_events) | |
234 | return NULL; | |
235 | ||
236 | /* | |
237 | * The ftrace subsystem is for showing formats only. | |
238 | * They can not be enabled or disabled via the event files. | |
239 | */ | |
240 | if (call->regfunc) | |
241 | break; | |
242 | ||
243 | call++; | |
244 | next = call; | |
245 | } | |
b77e38aa SR |
246 | |
247 | m->private = ++next; | |
248 | ||
249 | return call; | |
250 | } | |
251 | ||
252 | static void *t_start(struct seq_file *m, loff_t *pos) | |
253 | { | |
254 | return t_next(m, NULL, pos); | |
255 | } | |
256 | ||
257 | static void * | |
258 | s_next(struct seq_file *m, void *v, loff_t *pos) | |
259 | { | |
260 | struct ftrace_event_call *call = m->private; | |
261 | struct ftrace_event_call *next; | |
262 | ||
263 | (*pos)++; | |
264 | ||
265 | retry: | |
266 | if ((unsigned long)call >= (unsigned long)__stop_ftrace_events) | |
267 | return NULL; | |
268 | ||
269 | if (!call->enabled) { | |
270 | call++; | |
271 | goto retry; | |
272 | } | |
273 | ||
274 | next = call; | |
275 | m->private = ++next; | |
276 | ||
277 | return call; | |
278 | } | |
279 | ||
280 | static void *s_start(struct seq_file *m, loff_t *pos) | |
281 | { | |
282 | return s_next(m, NULL, pos); | |
283 | } | |
284 | ||
285 | static int t_show(struct seq_file *m, void *v) | |
286 | { | |
287 | struct ftrace_event_call *call = v; | |
288 | ||
b628b3e6 SR |
289 | if (strcmp(call->system, TRACE_SYSTEM) != 0) |
290 | seq_printf(m, "%s:", call->system); | |
b77e38aa SR |
291 | seq_printf(m, "%s\n", call->name); |
292 | ||
293 | return 0; | |
294 | } | |
295 | ||
296 | static void t_stop(struct seq_file *m, void *p) | |
297 | { | |
298 | } | |
299 | ||
300 | static int | |
301 | ftrace_event_seq_open(struct inode *inode, struct file *file) | |
302 | { | |
303 | int ret; | |
304 | const struct seq_operations *seq_ops; | |
305 | ||
306 | if ((file->f_mode & FMODE_WRITE) && | |
307 | !(file->f_flags & O_APPEND)) | |
308 | ftrace_clear_events(); | |
309 | ||
310 | seq_ops = inode->i_private; | |
311 | ret = seq_open(file, seq_ops); | |
312 | if (!ret) { | |
313 | struct seq_file *m = file->private_data; | |
314 | ||
315 | m->private = __start_ftrace_events; | |
316 | } | |
317 | return ret; | |
318 | } | |
319 | ||
1473e441 SR |
320 | static ssize_t |
321 | event_enable_read(struct file *filp, char __user *ubuf, size_t cnt, | |
322 | loff_t *ppos) | |
323 | { | |
324 | struct ftrace_event_call *call = filp->private_data; | |
325 | char *buf; | |
326 | ||
da4d0302 | 327 | if (call->enabled) |
1473e441 SR |
328 | buf = "1\n"; |
329 | else | |
330 | buf = "0\n"; | |
331 | ||
332 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
333 | } | |
334 | ||
335 | static ssize_t | |
336 | event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
337 | loff_t *ppos) | |
338 | { | |
339 | struct ftrace_event_call *call = filp->private_data; | |
340 | char buf[64]; | |
341 | unsigned long val; | |
342 | int ret; | |
343 | ||
344 | if (cnt >= sizeof(buf)) | |
345 | return -EINVAL; | |
346 | ||
347 | if (copy_from_user(&buf, ubuf, cnt)) | |
348 | return -EFAULT; | |
349 | ||
350 | buf[cnt] = 0; | |
351 | ||
352 | ret = strict_strtoul(buf, 10, &val); | |
353 | if (ret < 0) | |
354 | return ret; | |
355 | ||
1852fcce SR |
356 | ret = tracing_update_buffers(); |
357 | if (ret < 0) | |
358 | return ret; | |
359 | ||
1473e441 SR |
360 | switch (val) { |
361 | case 0: | |
1473e441 | 362 | case 1: |
11a241a3 | 363 | mutex_lock(&event_mutex); |
fd994989 | 364 | ftrace_event_enable_disable(call, val); |
11a241a3 | 365 | mutex_unlock(&event_mutex); |
1473e441 SR |
366 | break; |
367 | ||
368 | default: | |
369 | return -EINVAL; | |
370 | } | |
371 | ||
372 | *ppos += cnt; | |
373 | ||
374 | return cnt; | |
375 | } | |
376 | ||
91729ef9 | 377 | #undef FIELD |
156b5f17 | 378 | #define FIELD(type, name) \ |
cf027f64 TZ |
379 | #type, "common_" #name, offsetof(typeof(field), name), \ |
380 | sizeof(field.name) | |
91729ef9 SR |
381 | |
382 | static int trace_write_header(struct trace_seq *s) | |
383 | { | |
384 | struct trace_entry field; | |
385 | ||
386 | /* struct trace_entry */ | |
387 | return trace_seq_printf(s, | |
ce8eb2bf SR |
388 | "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n" |
389 | "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n" | |
390 | "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n" | |
391 | "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n" | |
392 | "\tfield:%s %s;\toffset:%zu;\tsize:%zu;\n" | |
91729ef9 SR |
393 | "\n", |
394 | FIELD(unsigned char, type), | |
395 | FIELD(unsigned char, flags), | |
396 | FIELD(unsigned char, preempt_count), | |
397 | FIELD(int, pid), | |
398 | FIELD(int, tgid)); | |
399 | } | |
da4d0302 | 400 | |
981d081e SR |
401 | static ssize_t |
402 | event_format_read(struct file *filp, char __user *ubuf, size_t cnt, | |
403 | loff_t *ppos) | |
404 | { | |
405 | struct ftrace_event_call *call = filp->private_data; | |
406 | struct trace_seq *s; | |
407 | char *buf; | |
408 | int r; | |
409 | ||
c269fc8c TZ |
410 | if (*ppos) |
411 | return 0; | |
412 | ||
981d081e SR |
413 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
414 | if (!s) | |
415 | return -ENOMEM; | |
416 | ||
417 | trace_seq_init(s); | |
418 | ||
c5e4e192 SR |
419 | /* If any of the first writes fail, so will the show_format. */ |
420 | ||
421 | trace_seq_printf(s, "name: %s\n", call->name); | |
422 | trace_seq_printf(s, "ID: %d\n", call->id); | |
423 | trace_seq_printf(s, "format:\n"); | |
91729ef9 SR |
424 | trace_write_header(s); |
425 | ||
981d081e SR |
426 | r = call->show_format(s); |
427 | if (!r) { | |
428 | /* | |
429 | * ug! The format output is bigger than a PAGE!! | |
430 | */ | |
431 | buf = "FORMAT TOO BIG\n"; | |
432 | r = simple_read_from_buffer(ubuf, cnt, ppos, | |
433 | buf, strlen(buf)); | |
434 | goto out; | |
435 | } | |
436 | ||
437 | r = simple_read_from_buffer(ubuf, cnt, ppos, | |
438 | s->buffer, s->len); | |
439 | out: | |
440 | kfree(s); | |
441 | return r; | |
442 | } | |
443 | ||
23725aee PZ |
444 | static ssize_t |
445 | event_id_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) | |
446 | { | |
447 | struct ftrace_event_call *call = filp->private_data; | |
448 | struct trace_seq *s; | |
449 | int r; | |
450 | ||
451 | if (*ppos) | |
452 | return 0; | |
453 | ||
454 | s = kmalloc(sizeof(*s), GFP_KERNEL); | |
455 | if (!s) | |
456 | return -ENOMEM; | |
457 | ||
458 | trace_seq_init(s); | |
459 | trace_seq_printf(s, "%d\n", call->id); | |
460 | ||
461 | r = simple_read_from_buffer(ubuf, cnt, ppos, | |
462 | s->buffer, s->len); | |
463 | kfree(s); | |
464 | return r; | |
465 | } | |
466 | ||
7ce7e424 TZ |
467 | static ssize_t |
468 | event_filter_read(struct file *filp, char __user *ubuf, size_t cnt, | |
469 | loff_t *ppos) | |
470 | { | |
471 | struct ftrace_event_call *call = filp->private_data; | |
472 | struct trace_seq *s; | |
473 | int r; | |
474 | ||
475 | if (*ppos) | |
476 | return 0; | |
477 | ||
478 | s = kmalloc(sizeof(*s), GFP_KERNEL); | |
479 | if (!s) | |
480 | return -ENOMEM; | |
481 | ||
482 | trace_seq_init(s); | |
483 | ||
484 | r = filter_print_preds(call->preds, s->buffer); | |
485 | r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, r); | |
486 | ||
487 | kfree(s); | |
488 | ||
489 | return r; | |
490 | } | |
491 | ||
492 | static ssize_t | |
493 | event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
494 | loff_t *ppos) | |
495 | { | |
496 | struct ftrace_event_call *call = filp->private_data; | |
497 | char buf[64], *pbuf = buf; | |
498 | struct filter_pred *pred; | |
499 | int err; | |
500 | ||
501 | if (cnt >= sizeof(buf)) | |
502 | return -EINVAL; | |
503 | ||
504 | if (copy_from_user(&buf, ubuf, cnt)) | |
505 | return -EFAULT; | |
506 | ||
507 | pred = kzalloc(sizeof(*pred), GFP_KERNEL); | |
508 | if (!pred) | |
509 | return -ENOMEM; | |
510 | ||
511 | err = filter_parse(&pbuf, pred); | |
512 | if (err < 0) { | |
513 | filter_free_pred(pred); | |
514 | return err; | |
515 | } | |
516 | ||
517 | if (pred->clear) { | |
518 | filter_free_preds(call); | |
09f1f245 | 519 | filter_free_pred(pred); |
7ce7e424 TZ |
520 | return cnt; |
521 | } | |
522 | ||
523 | if (filter_add_pred(call, pred)) { | |
524 | filter_free_pred(pred); | |
525 | return -EINVAL; | |
526 | } | |
527 | ||
528 | *ppos += cnt; | |
529 | ||
530 | return cnt; | |
531 | } | |
532 | ||
cfb180f3 TZ |
533 | static ssize_t |
534 | subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt, | |
535 | loff_t *ppos) | |
536 | { | |
537 | struct event_subsystem *system = filp->private_data; | |
538 | struct trace_seq *s; | |
539 | int r; | |
540 | ||
541 | if (*ppos) | |
542 | return 0; | |
543 | ||
544 | s = kmalloc(sizeof(*s), GFP_KERNEL); | |
545 | if (!s) | |
546 | return -ENOMEM; | |
547 | ||
548 | trace_seq_init(s); | |
549 | ||
550 | r = filter_print_preds(system->preds, s->buffer); | |
551 | r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, r); | |
552 | ||
553 | kfree(s); | |
554 | ||
555 | return r; | |
556 | } | |
557 | ||
558 | static ssize_t | |
559 | subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
560 | loff_t *ppos) | |
561 | { | |
562 | struct event_subsystem *system = filp->private_data; | |
563 | char buf[64], *pbuf = buf; | |
564 | struct filter_pred *pred; | |
565 | int err; | |
566 | ||
567 | if (cnt >= sizeof(buf)) | |
568 | return -EINVAL; | |
569 | ||
570 | if (copy_from_user(&buf, ubuf, cnt)) | |
571 | return -EFAULT; | |
572 | ||
573 | pred = kzalloc(sizeof(*pred), GFP_KERNEL); | |
574 | if (!pred) | |
575 | return -ENOMEM; | |
576 | ||
577 | err = filter_parse(&pbuf, pred); | |
578 | if (err < 0) { | |
579 | filter_free_pred(pred); | |
580 | return err; | |
581 | } | |
582 | ||
583 | if (pred->clear) { | |
584 | filter_free_subsystem_preds(system); | |
09f1f245 | 585 | filter_free_pred(pred); |
cfb180f3 TZ |
586 | return cnt; |
587 | } | |
588 | ||
589 | if (filter_add_subsystem_pred(system, pred)) { | |
c4cff064 | 590 | filter_free_subsystem_preds(system); |
cfb180f3 TZ |
591 | filter_free_pred(pred); |
592 | return -EINVAL; | |
593 | } | |
594 | ||
595 | *ppos += cnt; | |
596 | ||
597 | return cnt; | |
598 | } | |
599 | ||
b77e38aa SR |
600 | static const struct seq_operations show_event_seq_ops = { |
601 | .start = t_start, | |
602 | .next = t_next, | |
603 | .show = t_show, | |
604 | .stop = t_stop, | |
605 | }; | |
606 | ||
607 | static const struct seq_operations show_set_event_seq_ops = { | |
608 | .start = s_start, | |
609 | .next = s_next, | |
610 | .show = t_show, | |
611 | .stop = t_stop, | |
612 | }; | |
613 | ||
2314c4ae SR |
614 | static const struct file_operations ftrace_avail_fops = { |
615 | .open = ftrace_event_seq_open, | |
616 | .read = seq_read, | |
617 | .llseek = seq_lseek, | |
618 | .release = seq_release, | |
619 | }; | |
620 | ||
b77e38aa SR |
621 | static const struct file_operations ftrace_set_event_fops = { |
622 | .open = ftrace_event_seq_open, | |
623 | .read = seq_read, | |
624 | .write = ftrace_event_write, | |
625 | .llseek = seq_lseek, | |
626 | .release = seq_release, | |
627 | }; | |
628 | ||
1473e441 SR |
629 | static const struct file_operations ftrace_enable_fops = { |
630 | .open = tracing_open_generic, | |
631 | .read = event_enable_read, | |
632 | .write = event_enable_write, | |
633 | }; | |
634 | ||
981d081e SR |
635 | static const struct file_operations ftrace_event_format_fops = { |
636 | .open = tracing_open_generic, | |
637 | .read = event_format_read, | |
638 | }; | |
639 | ||
23725aee PZ |
640 | static const struct file_operations ftrace_event_id_fops = { |
641 | .open = tracing_open_generic, | |
642 | .read = event_id_read, | |
643 | }; | |
644 | ||
7ce7e424 TZ |
645 | static const struct file_operations ftrace_event_filter_fops = { |
646 | .open = tracing_open_generic, | |
647 | .read = event_filter_read, | |
648 | .write = event_filter_write, | |
649 | }; | |
650 | ||
cfb180f3 TZ |
651 | static const struct file_operations ftrace_subsystem_filter_fops = { |
652 | .open = tracing_open_generic, | |
653 | .read = subsystem_filter_read, | |
654 | .write = subsystem_filter_write, | |
655 | }; | |
656 | ||
1473e441 SR |
657 | static struct dentry *event_trace_events_dir(void) |
658 | { | |
659 | static struct dentry *d_tracer; | |
660 | static struct dentry *d_events; | |
661 | ||
662 | if (d_events) | |
663 | return d_events; | |
664 | ||
665 | d_tracer = tracing_init_dentry(); | |
666 | if (!d_tracer) | |
667 | return NULL; | |
668 | ||
669 | d_events = debugfs_create_dir("events", d_tracer); | |
670 | if (!d_events) | |
671 | pr_warning("Could not create debugfs " | |
672 | "'events' directory\n"); | |
673 | ||
674 | return d_events; | |
675 | } | |
676 | ||
6ecc2d1c SR |
677 | static LIST_HEAD(event_subsystems); |
678 | ||
679 | static struct dentry * | |
680 | event_subsystem_dir(const char *name, struct dentry *d_events) | |
681 | { | |
682 | struct event_subsystem *system; | |
cfb180f3 | 683 | struct dentry *entry; |
6ecc2d1c SR |
684 | |
685 | /* First see if we did not already create this dir */ | |
686 | list_for_each_entry(system, &event_subsystems, list) { | |
687 | if (strcmp(system->name, name) == 0) | |
688 | return system->entry; | |
689 | } | |
690 | ||
691 | /* need to create new entry */ | |
692 | system = kmalloc(sizeof(*system), GFP_KERNEL); | |
693 | if (!system) { | |
694 | pr_warning("No memory to create event subsystem %s\n", | |
695 | name); | |
696 | return d_events; | |
697 | } | |
698 | ||
699 | system->entry = debugfs_create_dir(name, d_events); | |
700 | if (!system->entry) { | |
701 | pr_warning("Could not create event subsystem %s\n", | |
702 | name); | |
703 | kfree(system); | |
704 | return d_events; | |
705 | } | |
706 | ||
707 | system->name = name; | |
708 | list_add(&system->list, &event_subsystems); | |
709 | ||
cfb180f3 TZ |
710 | system->preds = NULL; |
711 | ||
9bd7d099 | 712 | entry = debugfs_create_file("filter", 0644, system->entry, system, |
cfb180f3 TZ |
713 | &ftrace_subsystem_filter_fops); |
714 | if (!entry) | |
715 | pr_warning("Could not create debugfs " | |
716 | "'%s/filter' entry\n", name); | |
717 | ||
6ecc2d1c SR |
718 | return system->entry; |
719 | } | |
720 | ||
1473e441 SR |
721 | static int |
722 | event_create_dir(struct ftrace_event_call *call, struct dentry *d_events) | |
723 | { | |
724 | struct dentry *entry; | |
fd994989 | 725 | int ret; |
1473e441 | 726 | |
6ecc2d1c SR |
727 | /* |
728 | * If the trace point header did not define TRACE_SYSTEM | |
729 | * then the system would be called "TRACE_SYSTEM". | |
730 | */ | |
731 | if (strcmp(call->system, "TRACE_SYSTEM") != 0) | |
732 | d_events = event_subsystem_dir(call->system, d_events); | |
733 | ||
fd994989 SR |
734 | if (call->raw_init) { |
735 | ret = call->raw_init(); | |
736 | if (ret < 0) { | |
737 | pr_warning("Could not initialize trace point" | |
738 | " events/%s\n", call->name); | |
739 | return ret; | |
740 | } | |
741 | } | |
742 | ||
1473e441 SR |
743 | call->dir = debugfs_create_dir(call->name, d_events); |
744 | if (!call->dir) { | |
745 | pr_warning("Could not create debugfs " | |
746 | "'%s' directory\n", call->name); | |
747 | return -1; | |
748 | } | |
749 | ||
770cb243 SR |
750 | if (call->regfunc) { |
751 | entry = debugfs_create_file("enable", 0644, call->dir, call, | |
752 | &ftrace_enable_fops); | |
753 | if (!entry) | |
754 | pr_warning("Could not create debugfs " | |
755 | "'%s/enable' entry\n", call->name); | |
756 | } | |
1473e441 | 757 | |
23725aee PZ |
758 | if (call->id) { |
759 | entry = debugfs_create_file("id", 0444, call->dir, call, | |
760 | &ftrace_event_id_fops); | |
761 | if (!entry) | |
762 | pr_warning("Could not create debugfs '%s/id' entry\n", | |
763 | call->name); | |
764 | } | |
765 | ||
cf027f64 TZ |
766 | if (call->define_fields) { |
767 | ret = call->define_fields(); | |
768 | if (ret < 0) { | |
769 | pr_warning("Could not initialize trace point" | |
770 | " events/%s\n", call->name); | |
771 | return ret; | |
772 | } | |
773 | } | |
774 | ||
9bd7d099 | 775 | entry = debugfs_create_file("filter", 0644, call->dir, call, |
7ce7e424 TZ |
776 | &ftrace_event_filter_fops); |
777 | if (!entry) | |
778 | pr_warning("Could not create debugfs " | |
779 | "'%s/filter' entry\n", call->name); | |
780 | ||
981d081e SR |
781 | /* A trace may not want to export its format */ |
782 | if (!call->show_format) | |
783 | return 0; | |
784 | ||
785 | entry = debugfs_create_file("format", 0444, call->dir, call, | |
786 | &ftrace_event_format_fops); | |
787 | if (!entry) | |
788 | pr_warning("Could not create debugfs " | |
789 | "'%s/format' entry\n", call->name); | |
fd994989 | 790 | |
1473e441 SR |
791 | return 0; |
792 | } | |
793 | ||
b77e38aa SR |
794 | static __init int event_trace_init(void) |
795 | { | |
1473e441 | 796 | struct ftrace_event_call *call = __start_ftrace_events; |
b77e38aa SR |
797 | struct dentry *d_tracer; |
798 | struct dentry *entry; | |
1473e441 | 799 | struct dentry *d_events; |
b77e38aa SR |
800 | |
801 | d_tracer = tracing_init_dentry(); | |
802 | if (!d_tracer) | |
803 | return 0; | |
804 | ||
2314c4ae SR |
805 | entry = debugfs_create_file("available_events", 0444, d_tracer, |
806 | (void *)&show_event_seq_ops, | |
807 | &ftrace_avail_fops); | |
808 | if (!entry) | |
809 | pr_warning("Could not create debugfs " | |
810 | "'available_events' entry\n"); | |
811 | ||
b77e38aa SR |
812 | entry = debugfs_create_file("set_event", 0644, d_tracer, |
813 | (void *)&show_set_event_seq_ops, | |
814 | &ftrace_set_event_fops); | |
815 | if (!entry) | |
816 | pr_warning("Could not create debugfs " | |
817 | "'set_event' entry\n"); | |
818 | ||
1473e441 SR |
819 | d_events = event_trace_events_dir(); |
820 | if (!d_events) | |
821 | return 0; | |
822 | ||
ac199db0 | 823 | for_each_event(call) { |
1473e441 SR |
824 | /* The linker may leave blanks */ |
825 | if (!call->name) | |
826 | continue; | |
827 | event_create_dir(call, d_events); | |
828 | } | |
829 | ||
b77e38aa SR |
830 | return 0; |
831 | } | |
832 | fs_initcall(event_trace_init); |