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85f2b082 TZ |
1 | /* |
2 | * trace_events_trigger - trace event triggers | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify | |
5 | * it under the terms of the GNU General Public License as published by | |
6 | * the Free Software Foundation; either version 2 of the License, or | |
7 | * (at your option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, | |
10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
12 | * GNU General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License | |
15 | * along with this program; if not, write to the Free Software | |
16 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
17 | * | |
18 | * Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com> | |
19 | */ | |
20 | ||
21 | #include <linux/module.h> | |
22 | #include <linux/ctype.h> | |
23 | #include <linux/mutex.h> | |
24 | #include <linux/slab.h> | |
25 | ||
26 | #include "trace.h" | |
27 | ||
28 | static LIST_HEAD(trigger_commands); | |
29 | static DEFINE_MUTEX(trigger_cmd_mutex); | |
30 | ||
2a2df321 TZ |
31 | static void |
32 | trigger_data_free(struct event_trigger_data *data) | |
33 | { | |
bac5fb97 TZ |
34 | if (data->cmd_ops->set_filter) |
35 | data->cmd_ops->set_filter(NULL, data, NULL); | |
36 | ||
2a2df321 TZ |
37 | synchronize_sched(); /* make sure current triggers exit before free */ |
38 | kfree(data); | |
39 | } | |
40 | ||
85f2b082 TZ |
41 | /** |
42 | * event_triggers_call - Call triggers associated with a trace event | |
43 | * @file: The ftrace_event_file associated with the event | |
bac5fb97 | 44 | * @rec: The trace entry for the event, NULL for unconditional invocation |
85f2b082 TZ |
45 | * |
46 | * For each trigger associated with an event, invoke the trigger | |
bac5fb97 TZ |
47 | * function registered with the associated trigger command. If rec is |
48 | * non-NULL, it means that the trigger requires further processing and | |
49 | * shouldn't be unconditionally invoked. If rec is non-NULL and the | |
50 | * trigger has a filter associated with it, rec will checked against | |
51 | * the filter and if the record matches the trigger will be invoked. | |
52 | * If the trigger is a 'post_trigger', meaning it shouldn't be invoked | |
53 | * in any case until the current event is written, the trigger | |
54 | * function isn't invoked but the bit associated with the deferred | |
55 | * trigger is set in the return value. | |
56 | * | |
57 | * Returns an enum event_trigger_type value containing a set bit for | |
58 | * any trigger that should be deferred, ETT_NONE if nothing to defer. | |
85f2b082 TZ |
59 | * |
60 | * Called from tracepoint handlers (with rcu_read_lock_sched() held). | |
61 | * | |
62 | * Return: an enum event_trigger_type value containing a set bit for | |
63 | * any trigger that should be deferred, ETT_NONE if nothing to defer. | |
64 | */ | |
bac5fb97 TZ |
65 | enum event_trigger_type |
66 | event_triggers_call(struct ftrace_event_file *file, void *rec) | |
85f2b082 TZ |
67 | { |
68 | struct event_trigger_data *data; | |
bac5fb97 | 69 | enum event_trigger_type tt = ETT_NONE; |
85f2b082 TZ |
70 | |
71 | if (list_empty(&file->triggers)) | |
bac5fb97 | 72 | return tt; |
85f2b082 | 73 | |
bac5fb97 TZ |
74 | list_for_each_entry_rcu(data, &file->triggers, list) { |
75 | if (!rec) { | |
76 | data->ops->func(data); | |
77 | continue; | |
78 | } | |
79 | if (data->filter && !filter_match_preds(data->filter, rec)) | |
80 | continue; | |
81 | if (data->cmd_ops->post_trigger) { | |
82 | tt |= data->cmd_ops->trigger_type; | |
83 | continue; | |
84 | } | |
85f2b082 | 85 | data->ops->func(data); |
bac5fb97 TZ |
86 | } |
87 | return tt; | |
85f2b082 TZ |
88 | } |
89 | EXPORT_SYMBOL_GPL(event_triggers_call); | |
90 | ||
bac5fb97 TZ |
91 | /** |
92 | * event_triggers_post_call - Call 'post_triggers' for a trace event | |
93 | * @file: The ftrace_event_file associated with the event | |
94 | * @tt: enum event_trigger_type containing a set bit for each trigger to invoke | |
95 | * | |
96 | * For each trigger associated with an event, invoke the trigger | |
97 | * function registered with the associated trigger command, if the | |
98 | * corresponding bit is set in the tt enum passed into this function. | |
99 | * See @event_triggers_call for details on how those bits are set. | |
100 | * | |
101 | * Called from tracepoint handlers (with rcu_read_lock_sched() held). | |
102 | */ | |
103 | void | |
104 | event_triggers_post_call(struct ftrace_event_file *file, | |
105 | enum event_trigger_type tt) | |
106 | { | |
107 | struct event_trigger_data *data; | |
108 | ||
109 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
110 | if (data->cmd_ops->trigger_type & tt) | |
111 | data->ops->func(data); | |
112 | } | |
113 | } | |
114 | EXPORT_SYMBOL_GPL(event_triggers_post_call); | |
115 | ||
85f2b082 TZ |
116 | static void *trigger_next(struct seq_file *m, void *t, loff_t *pos) |
117 | { | |
118 | struct ftrace_event_file *event_file = event_file_data(m->private); | |
119 | ||
120 | return seq_list_next(t, &event_file->triggers, pos); | |
121 | } | |
122 | ||
123 | static void *trigger_start(struct seq_file *m, loff_t *pos) | |
124 | { | |
125 | struct ftrace_event_file *event_file; | |
126 | ||
127 | /* ->stop() is called even if ->start() fails */ | |
128 | mutex_lock(&event_mutex); | |
129 | event_file = event_file_data(m->private); | |
130 | if (unlikely(!event_file)) | |
131 | return ERR_PTR(-ENODEV); | |
132 | ||
133 | return seq_list_start(&event_file->triggers, *pos); | |
134 | } | |
135 | ||
136 | static void trigger_stop(struct seq_file *m, void *t) | |
137 | { | |
138 | mutex_unlock(&event_mutex); | |
139 | } | |
140 | ||
141 | static int trigger_show(struct seq_file *m, void *v) | |
142 | { | |
143 | struct event_trigger_data *data; | |
144 | ||
145 | data = list_entry(v, struct event_trigger_data, list); | |
146 | data->ops->print(m, data->ops, data); | |
147 | ||
148 | return 0; | |
149 | } | |
150 | ||
151 | static const struct seq_operations event_triggers_seq_ops = { | |
152 | .start = trigger_start, | |
153 | .next = trigger_next, | |
154 | .stop = trigger_stop, | |
155 | .show = trigger_show, | |
156 | }; | |
157 | ||
158 | static int event_trigger_regex_open(struct inode *inode, struct file *file) | |
159 | { | |
160 | int ret = 0; | |
161 | ||
162 | mutex_lock(&event_mutex); | |
163 | ||
164 | if (unlikely(!event_file_data(file))) { | |
165 | mutex_unlock(&event_mutex); | |
166 | return -ENODEV; | |
167 | } | |
168 | ||
169 | if (file->f_mode & FMODE_READ) { | |
170 | ret = seq_open(file, &event_triggers_seq_ops); | |
171 | if (!ret) { | |
172 | struct seq_file *m = file->private_data; | |
173 | m->private = file; | |
174 | } | |
175 | } | |
176 | ||
177 | mutex_unlock(&event_mutex); | |
178 | ||
179 | return ret; | |
180 | } | |
181 | ||
182 | static int trigger_process_regex(struct ftrace_event_file *file, char *buff) | |
183 | { | |
184 | char *command, *next = buff; | |
185 | struct event_command *p; | |
186 | int ret = -EINVAL; | |
187 | ||
188 | command = strsep(&next, ": \t"); | |
189 | command = (command[0] != '!') ? command : command + 1; | |
190 | ||
191 | mutex_lock(&trigger_cmd_mutex); | |
192 | list_for_each_entry(p, &trigger_commands, list) { | |
193 | if (strcmp(p->name, command) == 0) { | |
194 | ret = p->func(p, file, buff, command, next); | |
195 | goto out_unlock; | |
196 | } | |
197 | } | |
198 | out_unlock: | |
199 | mutex_unlock(&trigger_cmd_mutex); | |
200 | ||
201 | return ret; | |
202 | } | |
203 | ||
204 | static ssize_t event_trigger_regex_write(struct file *file, | |
205 | const char __user *ubuf, | |
206 | size_t cnt, loff_t *ppos) | |
207 | { | |
208 | struct ftrace_event_file *event_file; | |
209 | ssize_t ret; | |
210 | char *buf; | |
211 | ||
212 | if (!cnt) | |
213 | return 0; | |
214 | ||
215 | if (cnt >= PAGE_SIZE) | |
216 | return -EINVAL; | |
217 | ||
218 | buf = (char *)__get_free_page(GFP_TEMPORARY); | |
219 | if (!buf) | |
220 | return -ENOMEM; | |
221 | ||
222 | if (copy_from_user(buf, ubuf, cnt)) { | |
223 | free_page((unsigned long)buf); | |
224 | return -EFAULT; | |
225 | } | |
226 | buf[cnt] = '\0'; | |
227 | strim(buf); | |
228 | ||
229 | mutex_lock(&event_mutex); | |
230 | event_file = event_file_data(file); | |
231 | if (unlikely(!event_file)) { | |
232 | mutex_unlock(&event_mutex); | |
233 | free_page((unsigned long)buf); | |
234 | return -ENODEV; | |
235 | } | |
236 | ret = trigger_process_regex(event_file, buf); | |
237 | mutex_unlock(&event_mutex); | |
238 | ||
239 | free_page((unsigned long)buf); | |
240 | if (ret < 0) | |
241 | goto out; | |
242 | ||
243 | *ppos += cnt; | |
244 | ret = cnt; | |
245 | out: | |
246 | return ret; | |
247 | } | |
248 | ||
249 | static int event_trigger_regex_release(struct inode *inode, struct file *file) | |
250 | { | |
251 | mutex_lock(&event_mutex); | |
252 | ||
253 | if (file->f_mode & FMODE_READ) | |
254 | seq_release(inode, file); | |
255 | ||
256 | mutex_unlock(&event_mutex); | |
257 | ||
258 | return 0; | |
259 | } | |
260 | ||
261 | static ssize_t | |
262 | event_trigger_write(struct file *filp, const char __user *ubuf, | |
263 | size_t cnt, loff_t *ppos) | |
264 | { | |
265 | return event_trigger_regex_write(filp, ubuf, cnt, ppos); | |
266 | } | |
267 | ||
268 | static int | |
269 | event_trigger_open(struct inode *inode, struct file *filp) | |
270 | { | |
271 | return event_trigger_regex_open(inode, filp); | |
272 | } | |
273 | ||
274 | static int | |
275 | event_trigger_release(struct inode *inode, struct file *file) | |
276 | { | |
277 | return event_trigger_regex_release(inode, file); | |
278 | } | |
279 | ||
280 | const struct file_operations event_trigger_fops = { | |
281 | .open = event_trigger_open, | |
282 | .read = seq_read, | |
283 | .write = event_trigger_write, | |
098c879e | 284 | .llseek = tracing_lseek, |
85f2b082 TZ |
285 | .release = event_trigger_release, |
286 | }; | |
287 | ||
2a2df321 TZ |
288 | /* |
289 | * Currently we only register event commands from __init, so mark this | |
290 | * __init too. | |
291 | */ | |
292 | static __init int register_event_command(struct event_command *cmd) | |
293 | { | |
294 | struct event_command *p; | |
295 | int ret = 0; | |
296 | ||
297 | mutex_lock(&trigger_cmd_mutex); | |
298 | list_for_each_entry(p, &trigger_commands, list) { | |
299 | if (strcmp(cmd->name, p->name) == 0) { | |
300 | ret = -EBUSY; | |
301 | goto out_unlock; | |
302 | } | |
303 | } | |
304 | list_add(&cmd->list, &trigger_commands); | |
305 | out_unlock: | |
306 | mutex_unlock(&trigger_cmd_mutex); | |
307 | ||
308 | return ret; | |
309 | } | |
310 | ||
311 | /* | |
312 | * Currently we only unregister event commands from __init, so mark | |
313 | * this __init too. | |
314 | */ | |
315 | static __init int unregister_event_command(struct event_command *cmd) | |
316 | { | |
317 | struct event_command *p, *n; | |
318 | int ret = -ENODEV; | |
319 | ||
320 | mutex_lock(&trigger_cmd_mutex); | |
321 | list_for_each_entry_safe(p, n, &trigger_commands, list) { | |
322 | if (strcmp(cmd->name, p->name) == 0) { | |
323 | ret = 0; | |
324 | list_del_init(&p->list); | |
325 | goto out_unlock; | |
326 | } | |
327 | } | |
328 | out_unlock: | |
329 | mutex_unlock(&trigger_cmd_mutex); | |
330 | ||
331 | return ret; | |
332 | } | |
333 | ||
334 | /** | |
335 | * event_trigger_print - Generic event_trigger_ops @print implementation | |
336 | * @name: The name of the event trigger | |
337 | * @m: The seq_file being printed to | |
338 | * @data: Trigger-specific data | |
339 | * @filter_str: filter_str to print, if present | |
340 | * | |
341 | * Common implementation for event triggers to print themselves. | |
342 | * | |
343 | * Usually wrapped by a function that simply sets the @name of the | |
344 | * trigger command and then invokes this. | |
345 | * | |
346 | * Return: 0 on success, errno otherwise | |
347 | */ | |
348 | static int | |
349 | event_trigger_print(const char *name, struct seq_file *m, | |
350 | void *data, char *filter_str) | |
351 | { | |
352 | long count = (long)data; | |
353 | ||
354 | seq_printf(m, "%s", name); | |
355 | ||
356 | if (count == -1) | |
357 | seq_puts(m, ":unlimited"); | |
358 | else | |
359 | seq_printf(m, ":count=%ld", count); | |
360 | ||
361 | if (filter_str) | |
362 | seq_printf(m, " if %s\n", filter_str); | |
363 | else | |
364 | seq_puts(m, "\n"); | |
365 | ||
366 | return 0; | |
367 | } | |
368 | ||
369 | /** | |
370 | * event_trigger_init - Generic event_trigger_ops @init implementation | |
371 | * @ops: The trigger ops associated with the trigger | |
372 | * @data: Trigger-specific data | |
373 | * | |
374 | * Common implementation of event trigger initialization. | |
375 | * | |
376 | * Usually used directly as the @init method in event trigger | |
377 | * implementations. | |
378 | * | |
379 | * Return: 0 on success, errno otherwise | |
380 | */ | |
381 | static int | |
382 | event_trigger_init(struct event_trigger_ops *ops, | |
383 | struct event_trigger_data *data) | |
384 | { | |
385 | data->ref++; | |
386 | return 0; | |
387 | } | |
388 | ||
389 | /** | |
390 | * event_trigger_free - Generic event_trigger_ops @free implementation | |
391 | * @ops: The trigger ops associated with the trigger | |
392 | * @data: Trigger-specific data | |
393 | * | |
394 | * Common implementation of event trigger de-initialization. | |
395 | * | |
396 | * Usually used directly as the @free method in event trigger | |
397 | * implementations. | |
398 | */ | |
399 | static void | |
400 | event_trigger_free(struct event_trigger_ops *ops, | |
401 | struct event_trigger_data *data) | |
402 | { | |
403 | if (WARN_ON_ONCE(data->ref <= 0)) | |
404 | return; | |
405 | ||
406 | data->ref--; | |
407 | if (!data->ref) | |
408 | trigger_data_free(data); | |
409 | } | |
410 | ||
85f2b082 TZ |
411 | static int trace_event_trigger_enable_disable(struct ftrace_event_file *file, |
412 | int trigger_enable) | |
413 | { | |
414 | int ret = 0; | |
415 | ||
416 | if (trigger_enable) { | |
417 | if (atomic_inc_return(&file->tm_ref) > 1) | |
418 | return ret; | |
419 | set_bit(FTRACE_EVENT_FL_TRIGGER_MODE_BIT, &file->flags); | |
420 | ret = trace_event_enable_disable(file, 1, 1); | |
421 | } else { | |
422 | if (atomic_dec_return(&file->tm_ref) > 0) | |
423 | return ret; | |
424 | clear_bit(FTRACE_EVENT_FL_TRIGGER_MODE_BIT, &file->flags); | |
425 | ret = trace_event_enable_disable(file, 0, 1); | |
426 | } | |
427 | ||
428 | return ret; | |
429 | } | |
430 | ||
431 | /** | |
432 | * clear_event_triggers - Clear all triggers associated with a trace array | |
433 | * @tr: The trace array to clear | |
434 | * | |
435 | * For each trigger, the triggering event has its tm_ref decremented | |
436 | * via trace_event_trigger_enable_disable(), and any associated event | |
437 | * (in the case of enable/disable_event triggers) will have its sm_ref | |
438 | * decremented via free()->trace_event_enable_disable(). That | |
439 | * combination effectively reverses the soft-mode/trigger state added | |
440 | * by trigger registration. | |
441 | * | |
442 | * Must be called with event_mutex held. | |
443 | */ | |
444 | void | |
445 | clear_event_triggers(struct trace_array *tr) | |
446 | { | |
447 | struct ftrace_event_file *file; | |
448 | ||
449 | list_for_each_entry(file, &tr->events, list) { | |
450 | struct event_trigger_data *data; | |
451 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
452 | trace_event_trigger_enable_disable(file, 0); | |
453 | if (data->ops->free) | |
454 | data->ops->free(data->ops, data); | |
455 | } | |
456 | } | |
457 | } | |
458 | ||
bac5fb97 TZ |
459 | /** |
460 | * update_cond_flag - Set or reset the TRIGGER_COND bit | |
461 | * @file: The ftrace_event_file associated with the event | |
462 | * | |
463 | * If an event has triggers and any of those triggers has a filter or | |
464 | * a post_trigger, trigger invocation needs to be deferred until after | |
465 | * the current event has logged its data, and the event should have | |
466 | * its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be | |
467 | * cleared. | |
468 | */ | |
469 | static void update_cond_flag(struct ftrace_event_file *file) | |
470 | { | |
471 | struct event_trigger_data *data; | |
472 | bool set_cond = false; | |
473 | ||
474 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
475 | if (data->filter || data->cmd_ops->post_trigger) { | |
476 | set_cond = true; | |
477 | break; | |
478 | } | |
479 | } | |
480 | ||
481 | if (set_cond) | |
482 | set_bit(FTRACE_EVENT_FL_TRIGGER_COND_BIT, &file->flags); | |
483 | else | |
484 | clear_bit(FTRACE_EVENT_FL_TRIGGER_COND_BIT, &file->flags); | |
485 | } | |
486 | ||
2a2df321 TZ |
487 | /** |
488 | * register_trigger - Generic event_command @reg implementation | |
489 | * @glob: The raw string used to register the trigger | |
490 | * @ops: The trigger ops associated with the trigger | |
491 | * @data: Trigger-specific data to associate with the trigger | |
492 | * @file: The ftrace_event_file associated with the event | |
493 | * | |
494 | * Common implementation for event trigger registration. | |
495 | * | |
496 | * Usually used directly as the @reg method in event command | |
497 | * implementations. | |
498 | * | |
499 | * Return: 0 on success, errno otherwise | |
500 | */ | |
501 | static int register_trigger(char *glob, struct event_trigger_ops *ops, | |
502 | struct event_trigger_data *data, | |
503 | struct ftrace_event_file *file) | |
504 | { | |
505 | struct event_trigger_data *test; | |
506 | int ret = 0; | |
507 | ||
508 | list_for_each_entry_rcu(test, &file->triggers, list) { | |
509 | if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) { | |
510 | ret = -EEXIST; | |
511 | goto out; | |
512 | } | |
513 | } | |
514 | ||
515 | if (data->ops->init) { | |
516 | ret = data->ops->init(data->ops, data); | |
517 | if (ret < 0) | |
518 | goto out; | |
519 | } | |
520 | ||
521 | list_add_rcu(&data->list, &file->triggers); | |
522 | ret++; | |
523 | ||
524 | if (trace_event_trigger_enable_disable(file, 1) < 0) { | |
525 | list_del_rcu(&data->list); | |
526 | ret--; | |
527 | } | |
bac5fb97 | 528 | update_cond_flag(file); |
2a2df321 TZ |
529 | out: |
530 | return ret; | |
531 | } | |
532 | ||
533 | /** | |
534 | * unregister_trigger - Generic event_command @unreg implementation | |
535 | * @glob: The raw string used to register the trigger | |
536 | * @ops: The trigger ops associated with the trigger | |
537 | * @test: Trigger-specific data used to find the trigger to remove | |
538 | * @file: The ftrace_event_file associated with the event | |
539 | * | |
540 | * Common implementation for event trigger unregistration. | |
541 | * | |
542 | * Usually used directly as the @unreg method in event command | |
543 | * implementations. | |
544 | */ | |
545 | static void unregister_trigger(char *glob, struct event_trigger_ops *ops, | |
546 | struct event_trigger_data *test, | |
547 | struct ftrace_event_file *file) | |
548 | { | |
549 | struct event_trigger_data *data; | |
550 | bool unregistered = false; | |
551 | ||
552 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
553 | if (data->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { | |
554 | unregistered = true; | |
555 | list_del_rcu(&data->list); | |
bac5fb97 | 556 | update_cond_flag(file); |
2a2df321 TZ |
557 | trace_event_trigger_enable_disable(file, 0); |
558 | break; | |
559 | } | |
560 | } | |
561 | ||
562 | if (unregistered && data->ops->free) | |
563 | data->ops->free(data->ops, data); | |
564 | } | |
565 | ||
566 | /** | |
567 | * event_trigger_callback - Generic event_command @func implementation | |
568 | * @cmd_ops: The command ops, used for trigger registration | |
569 | * @file: The ftrace_event_file associated with the event | |
570 | * @glob: The raw string used to register the trigger | |
571 | * @cmd: The cmd portion of the string used to register the trigger | |
572 | * @param: The params portion of the string used to register the trigger | |
573 | * | |
574 | * Common implementation for event command parsing and trigger | |
575 | * instantiation. | |
576 | * | |
577 | * Usually used directly as the @func method in event command | |
578 | * implementations. | |
579 | * | |
580 | * Return: 0 on success, errno otherwise | |
581 | */ | |
582 | static int | |
583 | event_trigger_callback(struct event_command *cmd_ops, | |
584 | struct ftrace_event_file *file, | |
585 | char *glob, char *cmd, char *param) | |
586 | { | |
587 | struct event_trigger_data *trigger_data; | |
588 | struct event_trigger_ops *trigger_ops; | |
589 | char *trigger = NULL; | |
590 | char *number; | |
591 | int ret; | |
592 | ||
593 | /* separate the trigger from the filter (t:n [if filter]) */ | |
594 | if (param && isdigit(param[0])) | |
595 | trigger = strsep(¶m, " \t"); | |
596 | ||
597 | trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); | |
598 | ||
599 | ret = -ENOMEM; | |
600 | trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); | |
601 | if (!trigger_data) | |
602 | goto out; | |
603 | ||
604 | trigger_data->count = -1; | |
605 | trigger_data->ops = trigger_ops; | |
606 | trigger_data->cmd_ops = cmd_ops; | |
607 | INIT_LIST_HEAD(&trigger_data->list); | |
608 | ||
609 | if (glob[0] == '!') { | |
610 | cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); | |
611 | kfree(trigger_data); | |
612 | ret = 0; | |
613 | goto out; | |
614 | } | |
615 | ||
616 | if (trigger) { | |
617 | number = strsep(&trigger, ":"); | |
618 | ||
619 | ret = -EINVAL; | |
620 | if (!strlen(number)) | |
621 | goto out_free; | |
622 | ||
623 | /* | |
624 | * We use the callback data field (which is a pointer) | |
625 | * as our counter. | |
626 | */ | |
627 | ret = kstrtoul(number, 0, &trigger_data->count); | |
628 | if (ret) | |
629 | goto out_free; | |
630 | } | |
631 | ||
632 | if (!param) /* if param is non-empty, it's supposed to be a filter */ | |
633 | goto out_reg; | |
634 | ||
635 | if (!cmd_ops->set_filter) | |
636 | goto out_reg; | |
637 | ||
638 | ret = cmd_ops->set_filter(param, trigger_data, file); | |
639 | if (ret < 0) | |
640 | goto out_free; | |
641 | ||
642 | out_reg: | |
643 | ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); | |
644 | /* | |
645 | * The above returns on success the # of functions enabled, | |
646 | * but if it didn't find any functions it returns zero. | |
647 | * Consider no functions a failure too. | |
648 | */ | |
649 | if (!ret) { | |
650 | ret = -ENOENT; | |
651 | goto out_free; | |
652 | } else if (ret < 0) | |
653 | goto out_free; | |
654 | ret = 0; | |
655 | out: | |
656 | return ret; | |
657 | ||
658 | out_free: | |
bac5fb97 TZ |
659 | if (cmd_ops->set_filter) |
660 | cmd_ops->set_filter(NULL, trigger_data, NULL); | |
2a2df321 TZ |
661 | kfree(trigger_data); |
662 | goto out; | |
663 | } | |
664 | ||
bac5fb97 TZ |
665 | /** |
666 | * set_trigger_filter - Generic event_command @set_filter implementation | |
667 | * @filter_str: The filter string for the trigger, NULL to remove filter | |
668 | * @trigger_data: Trigger-specific data | |
669 | * @file: The ftrace_event_file associated with the event | |
670 | * | |
671 | * Common implementation for event command filter parsing and filter | |
672 | * instantiation. | |
673 | * | |
674 | * Usually used directly as the @set_filter method in event command | |
675 | * implementations. | |
676 | * | |
677 | * Also used to remove a filter (if filter_str = NULL). | |
678 | * | |
679 | * Return: 0 on success, errno otherwise | |
680 | */ | |
681 | static int set_trigger_filter(char *filter_str, | |
682 | struct event_trigger_data *trigger_data, | |
683 | struct ftrace_event_file *file) | |
684 | { | |
685 | struct event_trigger_data *data = trigger_data; | |
686 | struct event_filter *filter = NULL, *tmp; | |
687 | int ret = -EINVAL; | |
688 | char *s; | |
689 | ||
690 | if (!filter_str) /* clear the current filter */ | |
691 | goto assign; | |
692 | ||
693 | s = strsep(&filter_str, " \t"); | |
694 | ||
695 | if (!strlen(s) || strcmp(s, "if") != 0) | |
696 | goto out; | |
697 | ||
698 | if (!filter_str) | |
699 | goto out; | |
700 | ||
701 | /* The filter is for the 'trigger' event, not the triggered event */ | |
702 | ret = create_event_filter(file->event_call, filter_str, false, &filter); | |
703 | if (ret) | |
704 | goto out; | |
705 | assign: | |
706 | tmp = data->filter; | |
707 | ||
708 | rcu_assign_pointer(data->filter, filter); | |
709 | ||
710 | if (tmp) { | |
711 | /* Make sure the call is done with the filter */ | |
712 | synchronize_sched(); | |
713 | free_event_filter(tmp); | |
714 | } | |
715 | ||
716 | kfree(data->filter_str); | |
717 | data->filter_str = NULL; | |
718 | ||
719 | if (filter_str) { | |
720 | data->filter_str = kstrdup(filter_str, GFP_KERNEL); | |
721 | if (!data->filter_str) { | |
722 | free_event_filter(data->filter); | |
723 | data->filter = NULL; | |
724 | ret = -ENOMEM; | |
725 | } | |
726 | } | |
727 | out: | |
728 | return ret; | |
729 | } | |
730 | ||
2a2df321 TZ |
731 | static void |
732 | traceon_trigger(struct event_trigger_data *data) | |
733 | { | |
734 | if (tracing_is_on()) | |
735 | return; | |
736 | ||
737 | tracing_on(); | |
738 | } | |
739 | ||
740 | static void | |
741 | traceon_count_trigger(struct event_trigger_data *data) | |
742 | { | |
743 | if (!data->count) | |
744 | return; | |
745 | ||
746 | if (data->count != -1) | |
747 | (data->count)--; | |
748 | ||
749 | traceon_trigger(data); | |
750 | } | |
751 | ||
752 | static void | |
753 | traceoff_trigger(struct event_trigger_data *data) | |
754 | { | |
755 | if (!tracing_is_on()) | |
756 | return; | |
757 | ||
758 | tracing_off(); | |
759 | } | |
760 | ||
761 | static void | |
762 | traceoff_count_trigger(struct event_trigger_data *data) | |
763 | { | |
764 | if (!data->count) | |
765 | return; | |
766 | ||
767 | if (data->count != -1) | |
768 | (data->count)--; | |
769 | ||
770 | traceoff_trigger(data); | |
771 | } | |
772 | ||
773 | static int | |
774 | traceon_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
775 | struct event_trigger_data *data) | |
776 | { | |
777 | return event_trigger_print("traceon", m, (void *)data->count, | |
778 | data->filter_str); | |
779 | } | |
780 | ||
781 | static int | |
782 | traceoff_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
783 | struct event_trigger_data *data) | |
784 | { | |
785 | return event_trigger_print("traceoff", m, (void *)data->count, | |
786 | data->filter_str); | |
787 | } | |
788 | ||
789 | static struct event_trigger_ops traceon_trigger_ops = { | |
790 | .func = traceon_trigger, | |
791 | .print = traceon_trigger_print, | |
792 | .init = event_trigger_init, | |
793 | .free = event_trigger_free, | |
794 | }; | |
795 | ||
796 | static struct event_trigger_ops traceon_count_trigger_ops = { | |
797 | .func = traceon_count_trigger, | |
798 | .print = traceon_trigger_print, | |
799 | .init = event_trigger_init, | |
800 | .free = event_trigger_free, | |
801 | }; | |
802 | ||
803 | static struct event_trigger_ops traceoff_trigger_ops = { | |
804 | .func = traceoff_trigger, | |
805 | .print = traceoff_trigger_print, | |
806 | .init = event_trigger_init, | |
807 | .free = event_trigger_free, | |
808 | }; | |
809 | ||
810 | static struct event_trigger_ops traceoff_count_trigger_ops = { | |
811 | .func = traceoff_count_trigger, | |
812 | .print = traceoff_trigger_print, | |
813 | .init = event_trigger_init, | |
814 | .free = event_trigger_free, | |
815 | }; | |
816 | ||
817 | static struct event_trigger_ops * | |
818 | onoff_get_trigger_ops(char *cmd, char *param) | |
819 | { | |
820 | struct event_trigger_ops *ops; | |
821 | ||
822 | /* we register both traceon and traceoff to this callback */ | |
823 | if (strcmp(cmd, "traceon") == 0) | |
824 | ops = param ? &traceon_count_trigger_ops : | |
825 | &traceon_trigger_ops; | |
826 | else | |
827 | ops = param ? &traceoff_count_trigger_ops : | |
828 | &traceoff_trigger_ops; | |
829 | ||
830 | return ops; | |
831 | } | |
832 | ||
833 | static struct event_command trigger_traceon_cmd = { | |
834 | .name = "traceon", | |
835 | .trigger_type = ETT_TRACE_ONOFF, | |
836 | .func = event_trigger_callback, | |
837 | .reg = register_trigger, | |
838 | .unreg = unregister_trigger, | |
839 | .get_trigger_ops = onoff_get_trigger_ops, | |
bac5fb97 | 840 | .set_filter = set_trigger_filter, |
2a2df321 TZ |
841 | }; |
842 | ||
843 | static struct event_command trigger_traceoff_cmd = { | |
844 | .name = "traceoff", | |
845 | .trigger_type = ETT_TRACE_ONOFF, | |
846 | .func = event_trigger_callback, | |
847 | .reg = register_trigger, | |
848 | .unreg = unregister_trigger, | |
849 | .get_trigger_ops = onoff_get_trigger_ops, | |
bac5fb97 | 850 | .set_filter = set_trigger_filter, |
2a2df321 TZ |
851 | }; |
852 | ||
93e31ffb TZ |
853 | #ifdef CONFIG_TRACER_SNAPSHOT |
854 | static void | |
855 | snapshot_trigger(struct event_trigger_data *data) | |
856 | { | |
857 | tracing_snapshot(); | |
858 | } | |
859 | ||
860 | static void | |
861 | snapshot_count_trigger(struct event_trigger_data *data) | |
862 | { | |
863 | if (!data->count) | |
864 | return; | |
865 | ||
866 | if (data->count != -1) | |
867 | (data->count)--; | |
868 | ||
869 | snapshot_trigger(data); | |
870 | } | |
871 | ||
872 | static int | |
873 | register_snapshot_trigger(char *glob, struct event_trigger_ops *ops, | |
874 | struct event_trigger_data *data, | |
875 | struct ftrace_event_file *file) | |
876 | { | |
877 | int ret = register_trigger(glob, ops, data, file); | |
878 | ||
879 | if (ret > 0 && tracing_alloc_snapshot() != 0) { | |
880 | unregister_trigger(glob, ops, data, file); | |
881 | ret = 0; | |
882 | } | |
883 | ||
884 | return ret; | |
885 | } | |
886 | ||
887 | static int | |
888 | snapshot_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
889 | struct event_trigger_data *data) | |
890 | { | |
891 | return event_trigger_print("snapshot", m, (void *)data->count, | |
892 | data->filter_str); | |
893 | } | |
894 | ||
895 | static struct event_trigger_ops snapshot_trigger_ops = { | |
896 | .func = snapshot_trigger, | |
897 | .print = snapshot_trigger_print, | |
898 | .init = event_trigger_init, | |
899 | .free = event_trigger_free, | |
900 | }; | |
901 | ||
902 | static struct event_trigger_ops snapshot_count_trigger_ops = { | |
903 | .func = snapshot_count_trigger, | |
904 | .print = snapshot_trigger_print, | |
905 | .init = event_trigger_init, | |
906 | .free = event_trigger_free, | |
907 | }; | |
908 | ||
909 | static struct event_trigger_ops * | |
910 | snapshot_get_trigger_ops(char *cmd, char *param) | |
911 | { | |
912 | return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops; | |
913 | } | |
914 | ||
915 | static struct event_command trigger_snapshot_cmd = { | |
916 | .name = "snapshot", | |
917 | .trigger_type = ETT_SNAPSHOT, | |
918 | .func = event_trigger_callback, | |
919 | .reg = register_snapshot_trigger, | |
920 | .unreg = unregister_trigger, | |
921 | .get_trigger_ops = snapshot_get_trigger_ops, | |
bac5fb97 | 922 | .set_filter = set_trigger_filter, |
93e31ffb TZ |
923 | }; |
924 | ||
925 | static __init int register_trigger_snapshot_cmd(void) | |
926 | { | |
927 | int ret; | |
928 | ||
929 | ret = register_event_command(&trigger_snapshot_cmd); | |
930 | WARN_ON(ret < 0); | |
931 | ||
932 | return ret; | |
933 | } | |
934 | #else | |
935 | static __init int register_trigger_snapshot_cmd(void) { return 0; } | |
936 | #endif /* CONFIG_TRACER_SNAPSHOT */ | |
937 | ||
f21ecbb3 TZ |
938 | #ifdef CONFIG_STACKTRACE |
939 | /* | |
940 | * Skip 3: | |
941 | * stacktrace_trigger() | |
942 | * event_triggers_post_call() | |
943 | * ftrace_raw_event_xxx() | |
944 | */ | |
945 | #define STACK_SKIP 3 | |
946 | ||
947 | static void | |
948 | stacktrace_trigger(struct event_trigger_data *data) | |
949 | { | |
950 | trace_dump_stack(STACK_SKIP); | |
951 | } | |
952 | ||
953 | static void | |
954 | stacktrace_count_trigger(struct event_trigger_data *data) | |
955 | { | |
956 | if (!data->count) | |
957 | return; | |
958 | ||
959 | if (data->count != -1) | |
960 | (data->count)--; | |
961 | ||
962 | stacktrace_trigger(data); | |
963 | } | |
964 | ||
965 | static int | |
966 | stacktrace_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
967 | struct event_trigger_data *data) | |
968 | { | |
969 | return event_trigger_print("stacktrace", m, (void *)data->count, | |
970 | data->filter_str); | |
971 | } | |
972 | ||
973 | static struct event_trigger_ops stacktrace_trigger_ops = { | |
974 | .func = stacktrace_trigger, | |
975 | .print = stacktrace_trigger_print, | |
976 | .init = event_trigger_init, | |
977 | .free = event_trigger_free, | |
978 | }; | |
979 | ||
980 | static struct event_trigger_ops stacktrace_count_trigger_ops = { | |
981 | .func = stacktrace_count_trigger, | |
982 | .print = stacktrace_trigger_print, | |
983 | .init = event_trigger_init, | |
984 | .free = event_trigger_free, | |
985 | }; | |
986 | ||
987 | static struct event_trigger_ops * | |
988 | stacktrace_get_trigger_ops(char *cmd, char *param) | |
989 | { | |
990 | return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops; | |
991 | } | |
992 | ||
993 | static struct event_command trigger_stacktrace_cmd = { | |
994 | .name = "stacktrace", | |
995 | .trigger_type = ETT_STACKTRACE, | |
996 | .post_trigger = true, | |
997 | .func = event_trigger_callback, | |
998 | .reg = register_trigger, | |
999 | .unreg = unregister_trigger, | |
1000 | .get_trigger_ops = stacktrace_get_trigger_ops, | |
bac5fb97 | 1001 | .set_filter = set_trigger_filter, |
f21ecbb3 TZ |
1002 | }; |
1003 | ||
1004 | static __init int register_trigger_stacktrace_cmd(void) | |
1005 | { | |
1006 | int ret; | |
1007 | ||
1008 | ret = register_event_command(&trigger_stacktrace_cmd); | |
1009 | WARN_ON(ret < 0); | |
1010 | ||
1011 | return ret; | |
1012 | } | |
1013 | #else | |
1014 | static __init int register_trigger_stacktrace_cmd(void) { return 0; } | |
1015 | #endif /* CONFIG_STACKTRACE */ | |
1016 | ||
2a2df321 TZ |
1017 | static __init void unregister_trigger_traceon_traceoff_cmds(void) |
1018 | { | |
1019 | unregister_event_command(&trigger_traceon_cmd); | |
1020 | unregister_event_command(&trigger_traceoff_cmd); | |
1021 | } | |
1022 | ||
7862ad18 TZ |
1023 | /* Avoid typos */ |
1024 | #define ENABLE_EVENT_STR "enable_event" | |
1025 | #define DISABLE_EVENT_STR "disable_event" | |
1026 | ||
1027 | struct enable_trigger_data { | |
1028 | struct ftrace_event_file *file; | |
1029 | bool enable; | |
1030 | }; | |
1031 | ||
1032 | static void | |
1033 | event_enable_trigger(struct event_trigger_data *data) | |
1034 | { | |
1035 | struct enable_trigger_data *enable_data = data->private_data; | |
1036 | ||
1037 | if (enable_data->enable) | |
1038 | clear_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); | |
1039 | else | |
1040 | set_bit(FTRACE_EVENT_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); | |
1041 | } | |
1042 | ||
1043 | static void | |
1044 | event_enable_count_trigger(struct event_trigger_data *data) | |
1045 | { | |
1046 | struct enable_trigger_data *enable_data = data->private_data; | |
1047 | ||
1048 | if (!data->count) | |
1049 | return; | |
1050 | ||
1051 | /* Skip if the event is in a state we want to switch to */ | |
1052 | if (enable_data->enable == !(enable_data->file->flags & FTRACE_EVENT_FL_SOFT_DISABLED)) | |
1053 | return; | |
1054 | ||
1055 | if (data->count != -1) | |
1056 | (data->count)--; | |
1057 | ||
1058 | event_enable_trigger(data); | |
1059 | } | |
1060 | ||
1061 | static int | |
1062 | event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
1063 | struct event_trigger_data *data) | |
1064 | { | |
1065 | struct enable_trigger_data *enable_data = data->private_data; | |
1066 | ||
1067 | seq_printf(m, "%s:%s:%s", | |
1068 | enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, | |
1069 | enable_data->file->event_call->class->system, | |
1070 | enable_data->file->event_call->name); | |
1071 | ||
1072 | if (data->count == -1) | |
1073 | seq_puts(m, ":unlimited"); | |
1074 | else | |
1075 | seq_printf(m, ":count=%ld", data->count); | |
1076 | ||
1077 | if (data->filter_str) | |
1078 | seq_printf(m, " if %s\n", data->filter_str); | |
1079 | else | |
1080 | seq_puts(m, "\n"); | |
1081 | ||
1082 | return 0; | |
1083 | } | |
1084 | ||
1085 | static void | |
1086 | event_enable_trigger_free(struct event_trigger_ops *ops, | |
1087 | struct event_trigger_data *data) | |
1088 | { | |
1089 | struct enable_trigger_data *enable_data = data->private_data; | |
1090 | ||
1091 | if (WARN_ON_ONCE(data->ref <= 0)) | |
1092 | return; | |
1093 | ||
1094 | data->ref--; | |
1095 | if (!data->ref) { | |
1096 | /* Remove the SOFT_MODE flag */ | |
1097 | trace_event_enable_disable(enable_data->file, 0, 1); | |
1098 | module_put(enable_data->file->event_call->mod); | |
1099 | trigger_data_free(data); | |
1100 | kfree(enable_data); | |
1101 | } | |
1102 | } | |
1103 | ||
1104 | static struct event_trigger_ops event_enable_trigger_ops = { | |
1105 | .func = event_enable_trigger, | |
1106 | .print = event_enable_trigger_print, | |
1107 | .init = event_trigger_init, | |
1108 | .free = event_enable_trigger_free, | |
1109 | }; | |
1110 | ||
1111 | static struct event_trigger_ops event_enable_count_trigger_ops = { | |
1112 | .func = event_enable_count_trigger, | |
1113 | .print = event_enable_trigger_print, | |
1114 | .init = event_trigger_init, | |
1115 | .free = event_enable_trigger_free, | |
1116 | }; | |
1117 | ||
1118 | static struct event_trigger_ops event_disable_trigger_ops = { | |
1119 | .func = event_enable_trigger, | |
1120 | .print = event_enable_trigger_print, | |
1121 | .init = event_trigger_init, | |
1122 | .free = event_enable_trigger_free, | |
1123 | }; | |
1124 | ||
1125 | static struct event_trigger_ops event_disable_count_trigger_ops = { | |
1126 | .func = event_enable_count_trigger, | |
1127 | .print = event_enable_trigger_print, | |
1128 | .init = event_trigger_init, | |
1129 | .free = event_enable_trigger_free, | |
1130 | }; | |
1131 | ||
1132 | static int | |
1133 | event_enable_trigger_func(struct event_command *cmd_ops, | |
1134 | struct ftrace_event_file *file, | |
1135 | char *glob, char *cmd, char *param) | |
1136 | { | |
1137 | struct ftrace_event_file *event_enable_file; | |
1138 | struct enable_trigger_data *enable_data; | |
1139 | struct event_trigger_data *trigger_data; | |
1140 | struct event_trigger_ops *trigger_ops; | |
1141 | struct trace_array *tr = file->tr; | |
1142 | const char *system; | |
1143 | const char *event; | |
1144 | char *trigger; | |
1145 | char *number; | |
1146 | bool enable; | |
1147 | int ret; | |
1148 | ||
1149 | if (!param) | |
1150 | return -EINVAL; | |
1151 | ||
1152 | /* separate the trigger from the filter (s:e:n [if filter]) */ | |
1153 | trigger = strsep(¶m, " \t"); | |
1154 | if (!trigger) | |
1155 | return -EINVAL; | |
1156 | ||
1157 | system = strsep(&trigger, ":"); | |
1158 | if (!trigger) | |
1159 | return -EINVAL; | |
1160 | ||
1161 | event = strsep(&trigger, ":"); | |
1162 | ||
1163 | ret = -EINVAL; | |
1164 | event_enable_file = find_event_file(tr, system, event); | |
1165 | if (!event_enable_file) | |
1166 | goto out; | |
1167 | ||
1168 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; | |
1169 | ||
1170 | trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); | |
1171 | ||
1172 | ret = -ENOMEM; | |
1173 | trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); | |
1174 | if (!trigger_data) | |
1175 | goto out; | |
1176 | ||
1177 | enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL); | |
1178 | if (!enable_data) { | |
1179 | kfree(trigger_data); | |
1180 | goto out; | |
1181 | } | |
1182 | ||
1183 | trigger_data->count = -1; | |
1184 | trigger_data->ops = trigger_ops; | |
1185 | trigger_data->cmd_ops = cmd_ops; | |
1186 | INIT_LIST_HEAD(&trigger_data->list); | |
1187 | RCU_INIT_POINTER(trigger_data->filter, NULL); | |
1188 | ||
1189 | enable_data->enable = enable; | |
1190 | enable_data->file = event_enable_file; | |
1191 | trigger_data->private_data = enable_data; | |
1192 | ||
1193 | if (glob[0] == '!') { | |
1194 | cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); | |
1195 | kfree(trigger_data); | |
1196 | kfree(enable_data); | |
1197 | ret = 0; | |
1198 | goto out; | |
1199 | } | |
1200 | ||
1201 | if (trigger) { | |
1202 | number = strsep(&trigger, ":"); | |
1203 | ||
1204 | ret = -EINVAL; | |
1205 | if (!strlen(number)) | |
1206 | goto out_free; | |
1207 | ||
1208 | /* | |
1209 | * We use the callback data field (which is a pointer) | |
1210 | * as our counter. | |
1211 | */ | |
1212 | ret = kstrtoul(number, 0, &trigger_data->count); | |
1213 | if (ret) | |
1214 | goto out_free; | |
1215 | } | |
1216 | ||
1217 | if (!param) /* if param is non-empty, it's supposed to be a filter */ | |
1218 | goto out_reg; | |
1219 | ||
1220 | if (!cmd_ops->set_filter) | |
1221 | goto out_reg; | |
1222 | ||
1223 | ret = cmd_ops->set_filter(param, trigger_data, file); | |
1224 | if (ret < 0) | |
1225 | goto out_free; | |
1226 | ||
1227 | out_reg: | |
1228 | /* Don't let event modules unload while probe registered */ | |
1229 | ret = try_module_get(event_enable_file->event_call->mod); | |
1230 | if (!ret) { | |
1231 | ret = -EBUSY; | |
1232 | goto out_free; | |
1233 | } | |
1234 | ||
1235 | ret = trace_event_enable_disable(event_enable_file, 1, 1); | |
1236 | if (ret < 0) | |
1237 | goto out_put; | |
1238 | ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); | |
1239 | /* | |
1240 | * The above returns on success the # of functions enabled, | |
1241 | * but if it didn't find any functions it returns zero. | |
1242 | * Consider no functions a failure too. | |
1243 | */ | |
1244 | if (!ret) { | |
1245 | ret = -ENOENT; | |
1246 | goto out_disable; | |
1247 | } else if (ret < 0) | |
1248 | goto out_disable; | |
1249 | /* Just return zero, not the number of enabled functions */ | |
1250 | ret = 0; | |
1251 | out: | |
1252 | return ret; | |
1253 | ||
1254 | out_disable: | |
1255 | trace_event_enable_disable(event_enable_file, 0, 1); | |
1256 | out_put: | |
1257 | module_put(event_enable_file->event_call->mod); | |
1258 | out_free: | |
bac5fb97 TZ |
1259 | if (cmd_ops->set_filter) |
1260 | cmd_ops->set_filter(NULL, trigger_data, NULL); | |
7862ad18 TZ |
1261 | kfree(trigger_data); |
1262 | kfree(enable_data); | |
1263 | goto out; | |
1264 | } | |
1265 | ||
1266 | static int event_enable_register_trigger(char *glob, | |
1267 | struct event_trigger_ops *ops, | |
1268 | struct event_trigger_data *data, | |
1269 | struct ftrace_event_file *file) | |
1270 | { | |
1271 | struct enable_trigger_data *enable_data = data->private_data; | |
1272 | struct enable_trigger_data *test_enable_data; | |
1273 | struct event_trigger_data *test; | |
1274 | int ret = 0; | |
1275 | ||
1276 | list_for_each_entry_rcu(test, &file->triggers, list) { | |
1277 | test_enable_data = test->private_data; | |
1278 | if (test_enable_data && | |
1279 | (test_enable_data->file == enable_data->file)) { | |
1280 | ret = -EEXIST; | |
1281 | goto out; | |
1282 | } | |
1283 | } | |
1284 | ||
1285 | if (data->ops->init) { | |
1286 | ret = data->ops->init(data->ops, data); | |
1287 | if (ret < 0) | |
1288 | goto out; | |
1289 | } | |
1290 | ||
1291 | list_add_rcu(&data->list, &file->triggers); | |
1292 | ret++; | |
1293 | ||
1294 | if (trace_event_trigger_enable_disable(file, 1) < 0) { | |
1295 | list_del_rcu(&data->list); | |
1296 | ret--; | |
1297 | } | |
bac5fb97 | 1298 | update_cond_flag(file); |
7862ad18 TZ |
1299 | out: |
1300 | return ret; | |
1301 | } | |
1302 | ||
1303 | static void event_enable_unregister_trigger(char *glob, | |
1304 | struct event_trigger_ops *ops, | |
1305 | struct event_trigger_data *test, | |
1306 | struct ftrace_event_file *file) | |
1307 | { | |
1308 | struct enable_trigger_data *test_enable_data = test->private_data; | |
1309 | struct enable_trigger_data *enable_data; | |
1310 | struct event_trigger_data *data; | |
1311 | bool unregistered = false; | |
1312 | ||
1313 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
1314 | enable_data = data->private_data; | |
1315 | if (enable_data && | |
1316 | (enable_data->file == test_enable_data->file)) { | |
1317 | unregistered = true; | |
1318 | list_del_rcu(&data->list); | |
bac5fb97 | 1319 | update_cond_flag(file); |
7862ad18 TZ |
1320 | trace_event_trigger_enable_disable(file, 0); |
1321 | break; | |
1322 | } | |
1323 | } | |
1324 | ||
1325 | if (unregistered && data->ops->free) | |
1326 | data->ops->free(data->ops, data); | |
1327 | } | |
1328 | ||
1329 | static struct event_trigger_ops * | |
1330 | event_enable_get_trigger_ops(char *cmd, char *param) | |
1331 | { | |
1332 | struct event_trigger_ops *ops; | |
1333 | bool enable; | |
1334 | ||
1335 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; | |
1336 | ||
1337 | if (enable) | |
1338 | ops = param ? &event_enable_count_trigger_ops : | |
1339 | &event_enable_trigger_ops; | |
1340 | else | |
1341 | ops = param ? &event_disable_count_trigger_ops : | |
1342 | &event_disable_trigger_ops; | |
1343 | ||
1344 | return ops; | |
1345 | } | |
1346 | ||
1347 | static struct event_command trigger_enable_cmd = { | |
1348 | .name = ENABLE_EVENT_STR, | |
1349 | .trigger_type = ETT_EVENT_ENABLE, | |
1350 | .func = event_enable_trigger_func, | |
1351 | .reg = event_enable_register_trigger, | |
1352 | .unreg = event_enable_unregister_trigger, | |
1353 | .get_trigger_ops = event_enable_get_trigger_ops, | |
bac5fb97 | 1354 | .set_filter = set_trigger_filter, |
7862ad18 TZ |
1355 | }; |
1356 | ||
1357 | static struct event_command trigger_disable_cmd = { | |
1358 | .name = DISABLE_EVENT_STR, | |
1359 | .trigger_type = ETT_EVENT_ENABLE, | |
1360 | .func = event_enable_trigger_func, | |
1361 | .reg = event_enable_register_trigger, | |
1362 | .unreg = event_enable_unregister_trigger, | |
1363 | .get_trigger_ops = event_enable_get_trigger_ops, | |
bac5fb97 | 1364 | .set_filter = set_trigger_filter, |
7862ad18 TZ |
1365 | }; |
1366 | ||
1367 | static __init void unregister_trigger_enable_disable_cmds(void) | |
1368 | { | |
1369 | unregister_event_command(&trigger_enable_cmd); | |
1370 | unregister_event_command(&trigger_disable_cmd); | |
1371 | } | |
1372 | ||
1373 | static __init int register_trigger_enable_disable_cmds(void) | |
1374 | { | |
1375 | int ret; | |
1376 | ||
1377 | ret = register_event_command(&trigger_enable_cmd); | |
1378 | if (WARN_ON(ret < 0)) | |
1379 | return ret; | |
1380 | ret = register_event_command(&trigger_disable_cmd); | |
1381 | if (WARN_ON(ret < 0)) | |
1382 | unregister_trigger_enable_disable_cmds(); | |
1383 | ||
1384 | return ret; | |
1385 | } | |
1386 | ||
2a2df321 TZ |
1387 | static __init int register_trigger_traceon_traceoff_cmds(void) |
1388 | { | |
1389 | int ret; | |
1390 | ||
1391 | ret = register_event_command(&trigger_traceon_cmd); | |
1392 | if (WARN_ON(ret < 0)) | |
1393 | return ret; | |
1394 | ret = register_event_command(&trigger_traceoff_cmd); | |
1395 | if (WARN_ON(ret < 0)) | |
1396 | unregister_trigger_traceon_traceoff_cmds(); | |
1397 | ||
1398 | return ret; | |
1399 | } | |
1400 | ||
85f2b082 TZ |
1401 | __init int register_trigger_cmds(void) |
1402 | { | |
2a2df321 | 1403 | register_trigger_traceon_traceoff_cmds(); |
93e31ffb | 1404 | register_trigger_snapshot_cmd(); |
f21ecbb3 | 1405 | register_trigger_stacktrace_cmd(); |
7862ad18 | 1406 | register_trigger_enable_disable_cmds(); |
2a2df321 | 1407 | |
85f2b082 TZ |
1408 | return 0; |
1409 | } |