Commit | Line | Data |
---|---|---|
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 | |
7f1d2f82 | 43 | * @file: The trace_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 | 65 | enum event_trigger_type |
7f1d2f82 | 66 | event_triggers_call(struct trace_event_file *file, void *rec) |
85f2b082 TZ |
67 | { |
68 | struct event_trigger_data *data; | |
bac5fb97 | 69 | enum event_trigger_type tt = ETT_NONE; |
d8a30f20 | 70 | struct event_filter *filter; |
85f2b082 TZ |
71 | |
72 | if (list_empty(&file->triggers)) | |
bac5fb97 | 73 | return tt; |
85f2b082 | 74 | |
bac5fb97 TZ |
75 | list_for_each_entry_rcu(data, &file->triggers, list) { |
76 | if (!rec) { | |
77 | data->ops->func(data); | |
78 | continue; | |
79 | } | |
561a4fe8 | 80 | filter = rcu_dereference_sched(data->filter); |
d8a30f20 | 81 | if (filter && !filter_match_preds(filter, rec)) |
bac5fb97 TZ |
82 | continue; |
83 | if (data->cmd_ops->post_trigger) { | |
84 | tt |= data->cmd_ops->trigger_type; | |
85 | continue; | |
86 | } | |
85f2b082 | 87 | data->ops->func(data); |
bac5fb97 TZ |
88 | } |
89 | return tt; | |
85f2b082 TZ |
90 | } |
91 | EXPORT_SYMBOL_GPL(event_triggers_call); | |
92 | ||
bac5fb97 TZ |
93 | /** |
94 | * event_triggers_post_call - Call 'post_triggers' for a trace event | |
7f1d2f82 | 95 | * @file: The trace_event_file associated with the event |
bac5fb97 TZ |
96 | * @tt: enum event_trigger_type containing a set bit for each trigger to invoke |
97 | * | |
98 | * For each trigger associated with an event, invoke the trigger | |
99 | * function registered with the associated trigger command, if the | |
100 | * corresponding bit is set in the tt enum passed into this function. | |
101 | * See @event_triggers_call for details on how those bits are set. | |
102 | * | |
103 | * Called from tracepoint handlers (with rcu_read_lock_sched() held). | |
104 | */ | |
105 | void | |
7f1d2f82 | 106 | event_triggers_post_call(struct trace_event_file *file, |
bac5fb97 TZ |
107 | enum event_trigger_type tt) |
108 | { | |
109 | struct event_trigger_data *data; | |
110 | ||
111 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
112 | if (data->cmd_ops->trigger_type & tt) | |
113 | data->ops->func(data); | |
114 | } | |
115 | } | |
116 | EXPORT_SYMBOL_GPL(event_triggers_post_call); | |
117 | ||
dd97b954 SRRH |
118 | #define SHOW_AVAILABLE_TRIGGERS (void *)(1UL) |
119 | ||
85f2b082 TZ |
120 | static void *trigger_next(struct seq_file *m, void *t, loff_t *pos) |
121 | { | |
7f1d2f82 | 122 | struct trace_event_file *event_file = event_file_data(m->private); |
85f2b082 | 123 | |
dd97b954 SRRH |
124 | if (t == SHOW_AVAILABLE_TRIGGERS) |
125 | return NULL; | |
126 | ||
85f2b082 TZ |
127 | return seq_list_next(t, &event_file->triggers, pos); |
128 | } | |
129 | ||
130 | static void *trigger_start(struct seq_file *m, loff_t *pos) | |
131 | { | |
7f1d2f82 | 132 | struct trace_event_file *event_file; |
85f2b082 TZ |
133 | |
134 | /* ->stop() is called even if ->start() fails */ | |
135 | mutex_lock(&event_mutex); | |
136 | event_file = event_file_data(m->private); | |
137 | if (unlikely(!event_file)) | |
138 | return ERR_PTR(-ENODEV); | |
139 | ||
dd97b954 SRRH |
140 | if (list_empty(&event_file->triggers)) |
141 | return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL; | |
142 | ||
85f2b082 TZ |
143 | return seq_list_start(&event_file->triggers, *pos); |
144 | } | |
145 | ||
146 | static void trigger_stop(struct seq_file *m, void *t) | |
147 | { | |
148 | mutex_unlock(&event_mutex); | |
149 | } | |
150 | ||
151 | static int trigger_show(struct seq_file *m, void *v) | |
152 | { | |
153 | struct event_trigger_data *data; | |
dd97b954 SRRH |
154 | struct event_command *p; |
155 | ||
156 | if (v == SHOW_AVAILABLE_TRIGGERS) { | |
157 | seq_puts(m, "# Available triggers:\n"); | |
158 | seq_putc(m, '#'); | |
159 | mutex_lock(&trigger_cmd_mutex); | |
160 | list_for_each_entry_reverse(p, &trigger_commands, list) | |
161 | seq_printf(m, " %s", p->name); | |
162 | seq_putc(m, '\n'); | |
163 | mutex_unlock(&trigger_cmd_mutex); | |
164 | return 0; | |
165 | } | |
85f2b082 TZ |
166 | |
167 | data = list_entry(v, struct event_trigger_data, list); | |
168 | data->ops->print(m, data->ops, data); | |
169 | ||
170 | return 0; | |
171 | } | |
172 | ||
173 | static const struct seq_operations event_triggers_seq_ops = { | |
174 | .start = trigger_start, | |
175 | .next = trigger_next, | |
176 | .stop = trigger_stop, | |
177 | .show = trigger_show, | |
178 | }; | |
179 | ||
180 | static int event_trigger_regex_open(struct inode *inode, struct file *file) | |
181 | { | |
182 | int ret = 0; | |
183 | ||
184 | mutex_lock(&event_mutex); | |
185 | ||
186 | if (unlikely(!event_file_data(file))) { | |
187 | mutex_unlock(&event_mutex); | |
188 | return -ENODEV; | |
189 | } | |
190 | ||
191 | if (file->f_mode & FMODE_READ) { | |
192 | ret = seq_open(file, &event_triggers_seq_ops); | |
193 | if (!ret) { | |
194 | struct seq_file *m = file->private_data; | |
195 | m->private = file; | |
196 | } | |
197 | } | |
198 | ||
199 | mutex_unlock(&event_mutex); | |
200 | ||
201 | return ret; | |
202 | } | |
203 | ||
7f1d2f82 | 204 | static int trigger_process_regex(struct trace_event_file *file, char *buff) |
85f2b082 TZ |
205 | { |
206 | char *command, *next = buff; | |
207 | struct event_command *p; | |
208 | int ret = -EINVAL; | |
209 | ||
210 | command = strsep(&next, ": \t"); | |
211 | command = (command[0] != '!') ? command : command + 1; | |
212 | ||
213 | mutex_lock(&trigger_cmd_mutex); | |
214 | list_for_each_entry(p, &trigger_commands, list) { | |
215 | if (strcmp(p->name, command) == 0) { | |
216 | ret = p->func(p, file, buff, command, next); | |
217 | goto out_unlock; | |
218 | } | |
219 | } | |
220 | out_unlock: | |
221 | mutex_unlock(&trigger_cmd_mutex); | |
222 | ||
223 | return ret; | |
224 | } | |
225 | ||
226 | static ssize_t event_trigger_regex_write(struct file *file, | |
227 | const char __user *ubuf, | |
228 | size_t cnt, loff_t *ppos) | |
229 | { | |
7f1d2f82 | 230 | struct trace_event_file *event_file; |
85f2b082 TZ |
231 | ssize_t ret; |
232 | char *buf; | |
233 | ||
234 | if (!cnt) | |
235 | return 0; | |
236 | ||
237 | if (cnt >= PAGE_SIZE) | |
238 | return -EINVAL; | |
239 | ||
70f6cbb6 AV |
240 | buf = memdup_user_nul(ubuf, cnt); |
241 | if (IS_ERR(buf)) | |
242 | return PTR_ERR(buf); | |
85f2b082 | 243 | |
85f2b082 TZ |
244 | strim(buf); |
245 | ||
246 | mutex_lock(&event_mutex); | |
247 | event_file = event_file_data(file); | |
248 | if (unlikely(!event_file)) { | |
249 | mutex_unlock(&event_mutex); | |
70f6cbb6 | 250 | kfree(buf); |
85f2b082 TZ |
251 | return -ENODEV; |
252 | } | |
253 | ret = trigger_process_regex(event_file, buf); | |
254 | mutex_unlock(&event_mutex); | |
255 | ||
70f6cbb6 | 256 | kfree(buf); |
85f2b082 TZ |
257 | if (ret < 0) |
258 | goto out; | |
259 | ||
260 | *ppos += cnt; | |
261 | ret = cnt; | |
262 | out: | |
263 | return ret; | |
264 | } | |
265 | ||
266 | static int event_trigger_regex_release(struct inode *inode, struct file *file) | |
267 | { | |
268 | mutex_lock(&event_mutex); | |
269 | ||
270 | if (file->f_mode & FMODE_READ) | |
271 | seq_release(inode, file); | |
272 | ||
273 | mutex_unlock(&event_mutex); | |
274 | ||
275 | return 0; | |
276 | } | |
277 | ||
278 | static ssize_t | |
279 | event_trigger_write(struct file *filp, const char __user *ubuf, | |
280 | size_t cnt, loff_t *ppos) | |
281 | { | |
282 | return event_trigger_regex_write(filp, ubuf, cnt, ppos); | |
283 | } | |
284 | ||
285 | static int | |
286 | event_trigger_open(struct inode *inode, struct file *filp) | |
287 | { | |
288 | return event_trigger_regex_open(inode, filp); | |
289 | } | |
290 | ||
291 | static int | |
292 | event_trigger_release(struct inode *inode, struct file *file) | |
293 | { | |
294 | return event_trigger_regex_release(inode, file); | |
295 | } | |
296 | ||
297 | const struct file_operations event_trigger_fops = { | |
298 | .open = event_trigger_open, | |
299 | .read = seq_read, | |
300 | .write = event_trigger_write, | |
098c879e | 301 | .llseek = tracing_lseek, |
85f2b082 TZ |
302 | .release = event_trigger_release, |
303 | }; | |
304 | ||
2a2df321 TZ |
305 | /* |
306 | * Currently we only register event commands from __init, so mark this | |
307 | * __init too. | |
308 | */ | |
309 | static __init int register_event_command(struct event_command *cmd) | |
310 | { | |
311 | struct event_command *p; | |
312 | int ret = 0; | |
313 | ||
314 | mutex_lock(&trigger_cmd_mutex); | |
315 | list_for_each_entry(p, &trigger_commands, list) { | |
316 | if (strcmp(cmd->name, p->name) == 0) { | |
317 | ret = -EBUSY; | |
318 | goto out_unlock; | |
319 | } | |
320 | } | |
321 | list_add(&cmd->list, &trigger_commands); | |
322 | out_unlock: | |
323 | mutex_unlock(&trigger_cmd_mutex); | |
324 | ||
325 | return ret; | |
326 | } | |
327 | ||
328 | /* | |
329 | * Currently we only unregister event commands from __init, so mark | |
330 | * this __init too. | |
331 | */ | |
332 | static __init int unregister_event_command(struct event_command *cmd) | |
333 | { | |
334 | struct event_command *p, *n; | |
335 | int ret = -ENODEV; | |
336 | ||
337 | mutex_lock(&trigger_cmd_mutex); | |
338 | list_for_each_entry_safe(p, n, &trigger_commands, list) { | |
339 | if (strcmp(cmd->name, p->name) == 0) { | |
340 | ret = 0; | |
341 | list_del_init(&p->list); | |
342 | goto out_unlock; | |
343 | } | |
344 | } | |
345 | out_unlock: | |
346 | mutex_unlock(&trigger_cmd_mutex); | |
347 | ||
348 | return ret; | |
349 | } | |
350 | ||
351 | /** | |
352 | * event_trigger_print - Generic event_trigger_ops @print implementation | |
353 | * @name: The name of the event trigger | |
354 | * @m: The seq_file being printed to | |
355 | * @data: Trigger-specific data | |
356 | * @filter_str: filter_str to print, if present | |
357 | * | |
358 | * Common implementation for event triggers to print themselves. | |
359 | * | |
360 | * Usually wrapped by a function that simply sets the @name of the | |
361 | * trigger command and then invokes this. | |
362 | * | |
363 | * Return: 0 on success, errno otherwise | |
364 | */ | |
365 | static int | |
366 | event_trigger_print(const char *name, struct seq_file *m, | |
367 | void *data, char *filter_str) | |
368 | { | |
369 | long count = (long)data; | |
370 | ||
fa6f0cc7 | 371 | seq_puts(m, name); |
2a2df321 TZ |
372 | |
373 | if (count == -1) | |
374 | seq_puts(m, ":unlimited"); | |
375 | else | |
376 | seq_printf(m, ":count=%ld", count); | |
377 | ||
378 | if (filter_str) | |
379 | seq_printf(m, " if %s\n", filter_str); | |
380 | else | |
1177e436 | 381 | seq_putc(m, '\n'); |
2a2df321 TZ |
382 | |
383 | return 0; | |
384 | } | |
385 | ||
386 | /** | |
387 | * event_trigger_init - Generic event_trigger_ops @init implementation | |
388 | * @ops: The trigger ops associated with the trigger | |
389 | * @data: Trigger-specific data | |
390 | * | |
391 | * Common implementation of event trigger initialization. | |
392 | * | |
393 | * Usually used directly as the @init method in event trigger | |
394 | * implementations. | |
395 | * | |
396 | * Return: 0 on success, errno otherwise | |
397 | */ | |
398 | static int | |
399 | event_trigger_init(struct event_trigger_ops *ops, | |
400 | struct event_trigger_data *data) | |
401 | { | |
402 | data->ref++; | |
403 | return 0; | |
404 | } | |
405 | ||
406 | /** | |
407 | * event_trigger_free - Generic event_trigger_ops @free implementation | |
408 | * @ops: The trigger ops associated with the trigger | |
409 | * @data: Trigger-specific data | |
410 | * | |
411 | * Common implementation of event trigger de-initialization. | |
412 | * | |
413 | * Usually used directly as the @free method in event trigger | |
414 | * implementations. | |
415 | */ | |
416 | static void | |
417 | event_trigger_free(struct event_trigger_ops *ops, | |
418 | struct event_trigger_data *data) | |
419 | { | |
420 | if (WARN_ON_ONCE(data->ref <= 0)) | |
421 | return; | |
422 | ||
423 | data->ref--; | |
424 | if (!data->ref) | |
425 | trigger_data_free(data); | |
426 | } | |
427 | ||
7f1d2f82 | 428 | static int trace_event_trigger_enable_disable(struct trace_event_file *file, |
85f2b082 TZ |
429 | int trigger_enable) |
430 | { | |
431 | int ret = 0; | |
432 | ||
433 | if (trigger_enable) { | |
434 | if (atomic_inc_return(&file->tm_ref) > 1) | |
435 | return ret; | |
5d6ad960 | 436 | set_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags); |
85f2b082 TZ |
437 | ret = trace_event_enable_disable(file, 1, 1); |
438 | } else { | |
439 | if (atomic_dec_return(&file->tm_ref) > 0) | |
440 | return ret; | |
5d6ad960 | 441 | clear_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags); |
85f2b082 TZ |
442 | ret = trace_event_enable_disable(file, 0, 1); |
443 | } | |
444 | ||
445 | return ret; | |
446 | } | |
447 | ||
448 | /** | |
449 | * clear_event_triggers - Clear all triggers associated with a trace array | |
450 | * @tr: The trace array to clear | |
451 | * | |
452 | * For each trigger, the triggering event has its tm_ref decremented | |
453 | * via trace_event_trigger_enable_disable(), and any associated event | |
454 | * (in the case of enable/disable_event triggers) will have its sm_ref | |
455 | * decremented via free()->trace_event_enable_disable(). That | |
456 | * combination effectively reverses the soft-mode/trigger state added | |
457 | * by trigger registration. | |
458 | * | |
459 | * Must be called with event_mutex held. | |
460 | */ | |
461 | void | |
462 | clear_event_triggers(struct trace_array *tr) | |
463 | { | |
7f1d2f82 | 464 | struct trace_event_file *file; |
85f2b082 TZ |
465 | |
466 | list_for_each_entry(file, &tr->events, list) { | |
467 | struct event_trigger_data *data; | |
468 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
469 | trace_event_trigger_enable_disable(file, 0); | |
470 | if (data->ops->free) | |
471 | data->ops->free(data->ops, data); | |
472 | } | |
473 | } | |
474 | } | |
475 | ||
bac5fb97 TZ |
476 | /** |
477 | * update_cond_flag - Set or reset the TRIGGER_COND bit | |
7f1d2f82 | 478 | * @file: The trace_event_file associated with the event |
bac5fb97 TZ |
479 | * |
480 | * If an event has triggers and any of those triggers has a filter or | |
481 | * a post_trigger, trigger invocation needs to be deferred until after | |
482 | * the current event has logged its data, and the event should have | |
483 | * its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be | |
484 | * cleared. | |
485 | */ | |
7f1d2f82 | 486 | static void update_cond_flag(struct trace_event_file *file) |
bac5fb97 TZ |
487 | { |
488 | struct event_trigger_data *data; | |
489 | bool set_cond = false; | |
490 | ||
491 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
492 | if (data->filter || data->cmd_ops->post_trigger) { | |
493 | set_cond = true; | |
494 | break; | |
495 | } | |
496 | } | |
497 | ||
498 | if (set_cond) | |
5d6ad960 | 499 | set_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags); |
bac5fb97 | 500 | else |
5d6ad960 | 501 | clear_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags); |
bac5fb97 TZ |
502 | } |
503 | ||
2a2df321 TZ |
504 | /** |
505 | * register_trigger - Generic event_command @reg implementation | |
506 | * @glob: The raw string used to register the trigger | |
507 | * @ops: The trigger ops associated with the trigger | |
508 | * @data: Trigger-specific data to associate with the trigger | |
7f1d2f82 | 509 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
510 | * |
511 | * Common implementation for event trigger registration. | |
512 | * | |
513 | * Usually used directly as the @reg method in event command | |
514 | * implementations. | |
515 | * | |
516 | * Return: 0 on success, errno otherwise | |
517 | */ | |
518 | static int register_trigger(char *glob, struct event_trigger_ops *ops, | |
519 | struct event_trigger_data *data, | |
7f1d2f82 | 520 | struct trace_event_file *file) |
2a2df321 TZ |
521 | { |
522 | struct event_trigger_data *test; | |
523 | int ret = 0; | |
524 | ||
525 | list_for_each_entry_rcu(test, &file->triggers, list) { | |
526 | if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) { | |
527 | ret = -EEXIST; | |
528 | goto out; | |
529 | } | |
530 | } | |
531 | ||
532 | if (data->ops->init) { | |
533 | ret = data->ops->init(data->ops, data); | |
534 | if (ret < 0) | |
535 | goto out; | |
536 | } | |
537 | ||
538 | list_add_rcu(&data->list, &file->triggers); | |
539 | ret++; | |
540 | ||
541 | if (trace_event_trigger_enable_disable(file, 1) < 0) { | |
542 | list_del_rcu(&data->list); | |
543 | ret--; | |
544 | } | |
bac5fb97 | 545 | update_cond_flag(file); |
2a2df321 TZ |
546 | out: |
547 | return ret; | |
548 | } | |
549 | ||
550 | /** | |
551 | * unregister_trigger - Generic event_command @unreg implementation | |
552 | * @glob: The raw string used to register the trigger | |
553 | * @ops: The trigger ops associated with the trigger | |
554 | * @test: Trigger-specific data used to find the trigger to remove | |
7f1d2f82 | 555 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
556 | * |
557 | * Common implementation for event trigger unregistration. | |
558 | * | |
559 | * Usually used directly as the @unreg method in event command | |
560 | * implementations. | |
561 | */ | |
562 | static void unregister_trigger(char *glob, struct event_trigger_ops *ops, | |
563 | struct event_trigger_data *test, | |
7f1d2f82 | 564 | struct trace_event_file *file) |
2a2df321 TZ |
565 | { |
566 | struct event_trigger_data *data; | |
567 | bool unregistered = false; | |
568 | ||
569 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
570 | if (data->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { | |
571 | unregistered = true; | |
572 | list_del_rcu(&data->list); | |
bac5fb97 | 573 | update_cond_flag(file); |
2a2df321 TZ |
574 | trace_event_trigger_enable_disable(file, 0); |
575 | break; | |
576 | } | |
577 | } | |
578 | ||
579 | if (unregistered && data->ops->free) | |
580 | data->ops->free(data->ops, data); | |
581 | } | |
582 | ||
583 | /** | |
584 | * event_trigger_callback - Generic event_command @func implementation | |
585 | * @cmd_ops: The command ops, used for trigger registration | |
7f1d2f82 | 586 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
587 | * @glob: The raw string used to register the trigger |
588 | * @cmd: The cmd portion of the string used to register the trigger | |
589 | * @param: The params portion of the string used to register the trigger | |
590 | * | |
591 | * Common implementation for event command parsing and trigger | |
592 | * instantiation. | |
593 | * | |
594 | * Usually used directly as the @func method in event command | |
595 | * implementations. | |
596 | * | |
597 | * Return: 0 on success, errno otherwise | |
598 | */ | |
599 | static int | |
600 | event_trigger_callback(struct event_command *cmd_ops, | |
7f1d2f82 | 601 | struct trace_event_file *file, |
2a2df321 TZ |
602 | char *glob, char *cmd, char *param) |
603 | { | |
604 | struct event_trigger_data *trigger_data; | |
605 | struct event_trigger_ops *trigger_ops; | |
606 | char *trigger = NULL; | |
607 | char *number; | |
608 | int ret; | |
609 | ||
610 | /* separate the trigger from the filter (t:n [if filter]) */ | |
611 | if (param && isdigit(param[0])) | |
612 | trigger = strsep(¶m, " \t"); | |
613 | ||
614 | trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); | |
615 | ||
616 | ret = -ENOMEM; | |
617 | trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); | |
618 | if (!trigger_data) | |
619 | goto out; | |
620 | ||
621 | trigger_data->count = -1; | |
622 | trigger_data->ops = trigger_ops; | |
623 | trigger_data->cmd_ops = cmd_ops; | |
624 | INIT_LIST_HEAD(&trigger_data->list); | |
625 | ||
626 | if (glob[0] == '!') { | |
627 | cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); | |
628 | kfree(trigger_data); | |
629 | ret = 0; | |
630 | goto out; | |
631 | } | |
632 | ||
633 | if (trigger) { | |
634 | number = strsep(&trigger, ":"); | |
635 | ||
636 | ret = -EINVAL; | |
637 | if (!strlen(number)) | |
638 | goto out_free; | |
639 | ||
640 | /* | |
641 | * We use the callback data field (which is a pointer) | |
642 | * as our counter. | |
643 | */ | |
644 | ret = kstrtoul(number, 0, &trigger_data->count); | |
645 | if (ret) | |
646 | goto out_free; | |
647 | } | |
648 | ||
649 | if (!param) /* if param is non-empty, it's supposed to be a filter */ | |
650 | goto out_reg; | |
651 | ||
652 | if (!cmd_ops->set_filter) | |
653 | goto out_reg; | |
654 | ||
655 | ret = cmd_ops->set_filter(param, trigger_data, file); | |
656 | if (ret < 0) | |
657 | goto out_free; | |
658 | ||
659 | out_reg: | |
660 | ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); | |
661 | /* | |
662 | * The above returns on success the # of functions enabled, | |
663 | * but if it didn't find any functions it returns zero. | |
664 | * Consider no functions a failure too. | |
665 | */ | |
666 | if (!ret) { | |
667 | ret = -ENOENT; | |
668 | goto out_free; | |
669 | } else if (ret < 0) | |
670 | goto out_free; | |
671 | ret = 0; | |
672 | out: | |
673 | return ret; | |
674 | ||
675 | out_free: | |
bac5fb97 TZ |
676 | if (cmd_ops->set_filter) |
677 | cmd_ops->set_filter(NULL, trigger_data, NULL); | |
2a2df321 TZ |
678 | kfree(trigger_data); |
679 | goto out; | |
680 | } | |
681 | ||
bac5fb97 TZ |
682 | /** |
683 | * set_trigger_filter - Generic event_command @set_filter implementation | |
684 | * @filter_str: The filter string for the trigger, NULL to remove filter | |
685 | * @trigger_data: Trigger-specific data | |
7f1d2f82 | 686 | * @file: The trace_event_file associated with the event |
bac5fb97 TZ |
687 | * |
688 | * Common implementation for event command filter parsing and filter | |
689 | * instantiation. | |
690 | * | |
691 | * Usually used directly as the @set_filter method in event command | |
692 | * implementations. | |
693 | * | |
694 | * Also used to remove a filter (if filter_str = NULL). | |
695 | * | |
696 | * Return: 0 on success, errno otherwise | |
697 | */ | |
698 | static int set_trigger_filter(char *filter_str, | |
699 | struct event_trigger_data *trigger_data, | |
7f1d2f82 | 700 | struct trace_event_file *file) |
bac5fb97 TZ |
701 | { |
702 | struct event_trigger_data *data = trigger_data; | |
703 | struct event_filter *filter = NULL, *tmp; | |
704 | int ret = -EINVAL; | |
705 | char *s; | |
706 | ||
707 | if (!filter_str) /* clear the current filter */ | |
708 | goto assign; | |
709 | ||
710 | s = strsep(&filter_str, " \t"); | |
711 | ||
712 | if (!strlen(s) || strcmp(s, "if") != 0) | |
713 | goto out; | |
714 | ||
715 | if (!filter_str) | |
716 | goto out; | |
717 | ||
718 | /* The filter is for the 'trigger' event, not the triggered event */ | |
719 | ret = create_event_filter(file->event_call, filter_str, false, &filter); | |
720 | if (ret) | |
721 | goto out; | |
722 | assign: | |
d8a30f20 | 723 | tmp = rcu_access_pointer(data->filter); |
bac5fb97 TZ |
724 | |
725 | rcu_assign_pointer(data->filter, filter); | |
726 | ||
727 | if (tmp) { | |
728 | /* Make sure the call is done with the filter */ | |
729 | synchronize_sched(); | |
730 | free_event_filter(tmp); | |
731 | } | |
732 | ||
733 | kfree(data->filter_str); | |
734 | data->filter_str = NULL; | |
735 | ||
736 | if (filter_str) { | |
737 | data->filter_str = kstrdup(filter_str, GFP_KERNEL); | |
738 | if (!data->filter_str) { | |
d8a30f20 | 739 | free_event_filter(rcu_access_pointer(data->filter)); |
bac5fb97 TZ |
740 | data->filter = NULL; |
741 | ret = -ENOMEM; | |
742 | } | |
743 | } | |
744 | out: | |
745 | return ret; | |
746 | } | |
747 | ||
2a2df321 TZ |
748 | static void |
749 | traceon_trigger(struct event_trigger_data *data) | |
750 | { | |
751 | if (tracing_is_on()) | |
752 | return; | |
753 | ||
754 | tracing_on(); | |
755 | } | |
756 | ||
757 | static void | |
758 | traceon_count_trigger(struct event_trigger_data *data) | |
759 | { | |
e8dc6371 SRRH |
760 | if (tracing_is_on()) |
761 | return; | |
762 | ||
2a2df321 TZ |
763 | if (!data->count) |
764 | return; | |
765 | ||
766 | if (data->count != -1) | |
767 | (data->count)--; | |
768 | ||
e8dc6371 | 769 | tracing_on(); |
2a2df321 TZ |
770 | } |
771 | ||
772 | static void | |
773 | traceoff_trigger(struct event_trigger_data *data) | |
774 | { | |
775 | if (!tracing_is_on()) | |
776 | return; | |
777 | ||
778 | tracing_off(); | |
779 | } | |
780 | ||
781 | static void | |
782 | traceoff_count_trigger(struct event_trigger_data *data) | |
783 | { | |
e8dc6371 SRRH |
784 | if (!tracing_is_on()) |
785 | return; | |
786 | ||
2a2df321 TZ |
787 | if (!data->count) |
788 | return; | |
789 | ||
790 | if (data->count != -1) | |
791 | (data->count)--; | |
792 | ||
e8dc6371 | 793 | tracing_off(); |
2a2df321 TZ |
794 | } |
795 | ||
796 | static int | |
797 | traceon_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
798 | struct event_trigger_data *data) | |
799 | { | |
800 | return event_trigger_print("traceon", m, (void *)data->count, | |
801 | data->filter_str); | |
802 | } | |
803 | ||
804 | static int | |
805 | traceoff_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
806 | struct event_trigger_data *data) | |
807 | { | |
808 | return event_trigger_print("traceoff", m, (void *)data->count, | |
809 | data->filter_str); | |
810 | } | |
811 | ||
812 | static struct event_trigger_ops traceon_trigger_ops = { | |
813 | .func = traceon_trigger, | |
814 | .print = traceon_trigger_print, | |
815 | .init = event_trigger_init, | |
816 | .free = event_trigger_free, | |
817 | }; | |
818 | ||
819 | static struct event_trigger_ops traceon_count_trigger_ops = { | |
820 | .func = traceon_count_trigger, | |
821 | .print = traceon_trigger_print, | |
822 | .init = event_trigger_init, | |
823 | .free = event_trigger_free, | |
824 | }; | |
825 | ||
826 | static struct event_trigger_ops traceoff_trigger_ops = { | |
827 | .func = traceoff_trigger, | |
828 | .print = traceoff_trigger_print, | |
829 | .init = event_trigger_init, | |
830 | .free = event_trigger_free, | |
831 | }; | |
832 | ||
833 | static struct event_trigger_ops traceoff_count_trigger_ops = { | |
834 | .func = traceoff_count_trigger, | |
835 | .print = traceoff_trigger_print, | |
836 | .init = event_trigger_init, | |
837 | .free = event_trigger_free, | |
838 | }; | |
839 | ||
840 | static struct event_trigger_ops * | |
841 | onoff_get_trigger_ops(char *cmd, char *param) | |
842 | { | |
843 | struct event_trigger_ops *ops; | |
844 | ||
845 | /* we register both traceon and traceoff to this callback */ | |
846 | if (strcmp(cmd, "traceon") == 0) | |
847 | ops = param ? &traceon_count_trigger_ops : | |
848 | &traceon_trigger_ops; | |
849 | else | |
850 | ops = param ? &traceoff_count_trigger_ops : | |
851 | &traceoff_trigger_ops; | |
852 | ||
853 | return ops; | |
854 | } | |
855 | ||
856 | static struct event_command trigger_traceon_cmd = { | |
857 | .name = "traceon", | |
858 | .trigger_type = ETT_TRACE_ONOFF, | |
859 | .func = event_trigger_callback, | |
860 | .reg = register_trigger, | |
861 | .unreg = unregister_trigger, | |
862 | .get_trigger_ops = onoff_get_trigger_ops, | |
bac5fb97 | 863 | .set_filter = set_trigger_filter, |
2a2df321 TZ |
864 | }; |
865 | ||
866 | static struct event_command trigger_traceoff_cmd = { | |
867 | .name = "traceoff", | |
868 | .trigger_type = ETT_TRACE_ONOFF, | |
869 | .func = event_trigger_callback, | |
870 | .reg = register_trigger, | |
871 | .unreg = unregister_trigger, | |
872 | .get_trigger_ops = onoff_get_trigger_ops, | |
bac5fb97 | 873 | .set_filter = set_trigger_filter, |
2a2df321 TZ |
874 | }; |
875 | ||
93e31ffb TZ |
876 | #ifdef CONFIG_TRACER_SNAPSHOT |
877 | static void | |
878 | snapshot_trigger(struct event_trigger_data *data) | |
879 | { | |
880 | tracing_snapshot(); | |
881 | } | |
882 | ||
883 | static void | |
884 | snapshot_count_trigger(struct event_trigger_data *data) | |
885 | { | |
886 | if (!data->count) | |
887 | return; | |
888 | ||
889 | if (data->count != -1) | |
890 | (data->count)--; | |
891 | ||
892 | snapshot_trigger(data); | |
893 | } | |
894 | ||
895 | static int | |
896 | register_snapshot_trigger(char *glob, struct event_trigger_ops *ops, | |
897 | struct event_trigger_data *data, | |
7f1d2f82 | 898 | struct trace_event_file *file) |
93e31ffb TZ |
899 | { |
900 | int ret = register_trigger(glob, ops, data, file); | |
901 | ||
902 | if (ret > 0 && tracing_alloc_snapshot() != 0) { | |
903 | unregister_trigger(glob, ops, data, file); | |
904 | ret = 0; | |
905 | } | |
906 | ||
907 | return ret; | |
908 | } | |
909 | ||
910 | static int | |
911 | snapshot_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
912 | struct event_trigger_data *data) | |
913 | { | |
914 | return event_trigger_print("snapshot", m, (void *)data->count, | |
915 | data->filter_str); | |
916 | } | |
917 | ||
918 | static struct event_trigger_ops snapshot_trigger_ops = { | |
919 | .func = snapshot_trigger, | |
920 | .print = snapshot_trigger_print, | |
921 | .init = event_trigger_init, | |
922 | .free = event_trigger_free, | |
923 | }; | |
924 | ||
925 | static struct event_trigger_ops snapshot_count_trigger_ops = { | |
926 | .func = snapshot_count_trigger, | |
927 | .print = snapshot_trigger_print, | |
928 | .init = event_trigger_init, | |
929 | .free = event_trigger_free, | |
930 | }; | |
931 | ||
932 | static struct event_trigger_ops * | |
933 | snapshot_get_trigger_ops(char *cmd, char *param) | |
934 | { | |
935 | return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops; | |
936 | } | |
937 | ||
938 | static struct event_command trigger_snapshot_cmd = { | |
939 | .name = "snapshot", | |
940 | .trigger_type = ETT_SNAPSHOT, | |
941 | .func = event_trigger_callback, | |
942 | .reg = register_snapshot_trigger, | |
943 | .unreg = unregister_trigger, | |
944 | .get_trigger_ops = snapshot_get_trigger_ops, | |
bac5fb97 | 945 | .set_filter = set_trigger_filter, |
93e31ffb TZ |
946 | }; |
947 | ||
948 | static __init int register_trigger_snapshot_cmd(void) | |
949 | { | |
950 | int ret; | |
951 | ||
952 | ret = register_event_command(&trigger_snapshot_cmd); | |
953 | WARN_ON(ret < 0); | |
954 | ||
955 | return ret; | |
956 | } | |
957 | #else | |
958 | static __init int register_trigger_snapshot_cmd(void) { return 0; } | |
959 | #endif /* CONFIG_TRACER_SNAPSHOT */ | |
960 | ||
f21ecbb3 TZ |
961 | #ifdef CONFIG_STACKTRACE |
962 | /* | |
963 | * Skip 3: | |
964 | * stacktrace_trigger() | |
965 | * event_triggers_post_call() | |
a7237765 | 966 | * trace_event_raw_event_xxx() |
f21ecbb3 TZ |
967 | */ |
968 | #define STACK_SKIP 3 | |
969 | ||
970 | static void | |
971 | stacktrace_trigger(struct event_trigger_data *data) | |
972 | { | |
973 | trace_dump_stack(STACK_SKIP); | |
974 | } | |
975 | ||
976 | static void | |
977 | stacktrace_count_trigger(struct event_trigger_data *data) | |
978 | { | |
979 | if (!data->count) | |
980 | return; | |
981 | ||
982 | if (data->count != -1) | |
983 | (data->count)--; | |
984 | ||
985 | stacktrace_trigger(data); | |
986 | } | |
987 | ||
988 | static int | |
989 | stacktrace_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
990 | struct event_trigger_data *data) | |
991 | { | |
992 | return event_trigger_print("stacktrace", m, (void *)data->count, | |
993 | data->filter_str); | |
994 | } | |
995 | ||
996 | static struct event_trigger_ops stacktrace_trigger_ops = { | |
997 | .func = stacktrace_trigger, | |
998 | .print = stacktrace_trigger_print, | |
999 | .init = event_trigger_init, | |
1000 | .free = event_trigger_free, | |
1001 | }; | |
1002 | ||
1003 | static struct event_trigger_ops stacktrace_count_trigger_ops = { | |
1004 | .func = stacktrace_count_trigger, | |
1005 | .print = stacktrace_trigger_print, | |
1006 | .init = event_trigger_init, | |
1007 | .free = event_trigger_free, | |
1008 | }; | |
1009 | ||
1010 | static struct event_trigger_ops * | |
1011 | stacktrace_get_trigger_ops(char *cmd, char *param) | |
1012 | { | |
1013 | return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops; | |
1014 | } | |
1015 | ||
1016 | static struct event_command trigger_stacktrace_cmd = { | |
1017 | .name = "stacktrace", | |
1018 | .trigger_type = ETT_STACKTRACE, | |
1019 | .post_trigger = true, | |
1020 | .func = event_trigger_callback, | |
1021 | .reg = register_trigger, | |
1022 | .unreg = unregister_trigger, | |
1023 | .get_trigger_ops = stacktrace_get_trigger_ops, | |
bac5fb97 | 1024 | .set_filter = set_trigger_filter, |
f21ecbb3 TZ |
1025 | }; |
1026 | ||
1027 | static __init int register_trigger_stacktrace_cmd(void) | |
1028 | { | |
1029 | int ret; | |
1030 | ||
1031 | ret = register_event_command(&trigger_stacktrace_cmd); | |
1032 | WARN_ON(ret < 0); | |
1033 | ||
1034 | return ret; | |
1035 | } | |
1036 | #else | |
1037 | static __init int register_trigger_stacktrace_cmd(void) { return 0; } | |
1038 | #endif /* CONFIG_STACKTRACE */ | |
1039 | ||
2a2df321 TZ |
1040 | static __init void unregister_trigger_traceon_traceoff_cmds(void) |
1041 | { | |
1042 | unregister_event_command(&trigger_traceon_cmd); | |
1043 | unregister_event_command(&trigger_traceoff_cmd); | |
1044 | } | |
1045 | ||
7862ad18 TZ |
1046 | /* Avoid typos */ |
1047 | #define ENABLE_EVENT_STR "enable_event" | |
1048 | #define DISABLE_EVENT_STR "disable_event" | |
1049 | ||
1050 | struct enable_trigger_data { | |
7f1d2f82 | 1051 | struct trace_event_file *file; |
7862ad18 TZ |
1052 | bool enable; |
1053 | }; | |
1054 | ||
1055 | static void | |
1056 | event_enable_trigger(struct event_trigger_data *data) | |
1057 | { | |
1058 | struct enable_trigger_data *enable_data = data->private_data; | |
1059 | ||
1060 | if (enable_data->enable) | |
5d6ad960 | 1061 | clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); |
7862ad18 | 1062 | else |
5d6ad960 | 1063 | set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); |
7862ad18 TZ |
1064 | } |
1065 | ||
1066 | static void | |
1067 | event_enable_count_trigger(struct event_trigger_data *data) | |
1068 | { | |
1069 | struct enable_trigger_data *enable_data = data->private_data; | |
1070 | ||
1071 | if (!data->count) | |
1072 | return; | |
1073 | ||
1074 | /* Skip if the event is in a state we want to switch to */ | |
5d6ad960 | 1075 | if (enable_data->enable == !(enable_data->file->flags & EVENT_FILE_FL_SOFT_DISABLED)) |
7862ad18 TZ |
1076 | return; |
1077 | ||
1078 | if (data->count != -1) | |
1079 | (data->count)--; | |
1080 | ||
1081 | event_enable_trigger(data); | |
1082 | } | |
1083 | ||
1084 | static int | |
1085 | event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
1086 | struct event_trigger_data *data) | |
1087 | { | |
1088 | struct enable_trigger_data *enable_data = data->private_data; | |
1089 | ||
1090 | seq_printf(m, "%s:%s:%s", | |
1091 | enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, | |
1092 | enable_data->file->event_call->class->system, | |
687fcc4a | 1093 | trace_event_name(enable_data->file->event_call)); |
7862ad18 TZ |
1094 | |
1095 | if (data->count == -1) | |
1096 | seq_puts(m, ":unlimited"); | |
1097 | else | |
1098 | seq_printf(m, ":count=%ld", data->count); | |
1099 | ||
1100 | if (data->filter_str) | |
1101 | seq_printf(m, " if %s\n", data->filter_str); | |
1102 | else | |
1177e436 | 1103 | seq_putc(m, '\n'); |
7862ad18 TZ |
1104 | |
1105 | return 0; | |
1106 | } | |
1107 | ||
1108 | static void | |
1109 | event_enable_trigger_free(struct event_trigger_ops *ops, | |
1110 | struct event_trigger_data *data) | |
1111 | { | |
1112 | struct enable_trigger_data *enable_data = data->private_data; | |
1113 | ||
1114 | if (WARN_ON_ONCE(data->ref <= 0)) | |
1115 | return; | |
1116 | ||
1117 | data->ref--; | |
1118 | if (!data->ref) { | |
1119 | /* Remove the SOFT_MODE flag */ | |
1120 | trace_event_enable_disable(enable_data->file, 0, 1); | |
1121 | module_put(enable_data->file->event_call->mod); | |
1122 | trigger_data_free(data); | |
1123 | kfree(enable_data); | |
1124 | } | |
1125 | } | |
1126 | ||
1127 | static struct event_trigger_ops event_enable_trigger_ops = { | |
1128 | .func = event_enable_trigger, | |
1129 | .print = event_enable_trigger_print, | |
1130 | .init = event_trigger_init, | |
1131 | .free = event_enable_trigger_free, | |
1132 | }; | |
1133 | ||
1134 | static struct event_trigger_ops event_enable_count_trigger_ops = { | |
1135 | .func = event_enable_count_trigger, | |
1136 | .print = event_enable_trigger_print, | |
1137 | .init = event_trigger_init, | |
1138 | .free = event_enable_trigger_free, | |
1139 | }; | |
1140 | ||
1141 | static struct event_trigger_ops event_disable_trigger_ops = { | |
1142 | .func = event_enable_trigger, | |
1143 | .print = event_enable_trigger_print, | |
1144 | .init = event_trigger_init, | |
1145 | .free = event_enable_trigger_free, | |
1146 | }; | |
1147 | ||
1148 | static struct event_trigger_ops event_disable_count_trigger_ops = { | |
1149 | .func = event_enable_count_trigger, | |
1150 | .print = event_enable_trigger_print, | |
1151 | .init = event_trigger_init, | |
1152 | .free = event_enable_trigger_free, | |
1153 | }; | |
1154 | ||
1155 | static int | |
1156 | event_enable_trigger_func(struct event_command *cmd_ops, | |
7f1d2f82 | 1157 | struct trace_event_file *file, |
7862ad18 TZ |
1158 | char *glob, char *cmd, char *param) |
1159 | { | |
7f1d2f82 | 1160 | struct trace_event_file *event_enable_file; |
7862ad18 TZ |
1161 | struct enable_trigger_data *enable_data; |
1162 | struct event_trigger_data *trigger_data; | |
1163 | struct event_trigger_ops *trigger_ops; | |
1164 | struct trace_array *tr = file->tr; | |
1165 | const char *system; | |
1166 | const char *event; | |
1167 | char *trigger; | |
1168 | char *number; | |
1169 | bool enable; | |
1170 | int ret; | |
1171 | ||
1172 | if (!param) | |
1173 | return -EINVAL; | |
1174 | ||
1175 | /* separate the trigger from the filter (s:e:n [if filter]) */ | |
1176 | trigger = strsep(¶m, " \t"); | |
1177 | if (!trigger) | |
1178 | return -EINVAL; | |
1179 | ||
1180 | system = strsep(&trigger, ":"); | |
1181 | if (!trigger) | |
1182 | return -EINVAL; | |
1183 | ||
1184 | event = strsep(&trigger, ":"); | |
1185 | ||
1186 | ret = -EINVAL; | |
1187 | event_enable_file = find_event_file(tr, system, event); | |
1188 | if (!event_enable_file) | |
1189 | goto out; | |
1190 | ||
1191 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; | |
1192 | ||
1193 | trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); | |
1194 | ||
1195 | ret = -ENOMEM; | |
1196 | trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); | |
1197 | if (!trigger_data) | |
1198 | goto out; | |
1199 | ||
1200 | enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL); | |
1201 | if (!enable_data) { | |
1202 | kfree(trigger_data); | |
1203 | goto out; | |
1204 | } | |
1205 | ||
1206 | trigger_data->count = -1; | |
1207 | trigger_data->ops = trigger_ops; | |
1208 | trigger_data->cmd_ops = cmd_ops; | |
1209 | INIT_LIST_HEAD(&trigger_data->list); | |
1210 | RCU_INIT_POINTER(trigger_data->filter, NULL); | |
1211 | ||
1212 | enable_data->enable = enable; | |
1213 | enable_data->file = event_enable_file; | |
1214 | trigger_data->private_data = enable_data; | |
1215 | ||
1216 | if (glob[0] == '!') { | |
1217 | cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); | |
1218 | kfree(trigger_data); | |
1219 | kfree(enable_data); | |
1220 | ret = 0; | |
1221 | goto out; | |
1222 | } | |
1223 | ||
1224 | if (trigger) { | |
1225 | number = strsep(&trigger, ":"); | |
1226 | ||
1227 | ret = -EINVAL; | |
1228 | if (!strlen(number)) | |
1229 | goto out_free; | |
1230 | ||
1231 | /* | |
1232 | * We use the callback data field (which is a pointer) | |
1233 | * as our counter. | |
1234 | */ | |
1235 | ret = kstrtoul(number, 0, &trigger_data->count); | |
1236 | if (ret) | |
1237 | goto out_free; | |
1238 | } | |
1239 | ||
1240 | if (!param) /* if param is non-empty, it's supposed to be a filter */ | |
1241 | goto out_reg; | |
1242 | ||
1243 | if (!cmd_ops->set_filter) | |
1244 | goto out_reg; | |
1245 | ||
1246 | ret = cmd_ops->set_filter(param, trigger_data, file); | |
1247 | if (ret < 0) | |
1248 | goto out_free; | |
1249 | ||
1250 | out_reg: | |
1251 | /* Don't let event modules unload while probe registered */ | |
1252 | ret = try_module_get(event_enable_file->event_call->mod); | |
1253 | if (!ret) { | |
1254 | ret = -EBUSY; | |
1255 | goto out_free; | |
1256 | } | |
1257 | ||
1258 | ret = trace_event_enable_disable(event_enable_file, 1, 1); | |
1259 | if (ret < 0) | |
1260 | goto out_put; | |
1261 | ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); | |
1262 | /* | |
1263 | * The above returns on success the # of functions enabled, | |
1264 | * but if it didn't find any functions it returns zero. | |
1265 | * Consider no functions a failure too. | |
1266 | */ | |
1267 | if (!ret) { | |
1268 | ret = -ENOENT; | |
1269 | goto out_disable; | |
1270 | } else if (ret < 0) | |
1271 | goto out_disable; | |
1272 | /* Just return zero, not the number of enabled functions */ | |
1273 | ret = 0; | |
1274 | out: | |
1275 | return ret; | |
1276 | ||
1277 | out_disable: | |
1278 | trace_event_enable_disable(event_enable_file, 0, 1); | |
1279 | out_put: | |
1280 | module_put(event_enable_file->event_call->mod); | |
1281 | out_free: | |
bac5fb97 TZ |
1282 | if (cmd_ops->set_filter) |
1283 | cmd_ops->set_filter(NULL, trigger_data, NULL); | |
7862ad18 TZ |
1284 | kfree(trigger_data); |
1285 | kfree(enable_data); | |
1286 | goto out; | |
1287 | } | |
1288 | ||
1289 | static int event_enable_register_trigger(char *glob, | |
1290 | struct event_trigger_ops *ops, | |
1291 | struct event_trigger_data *data, | |
7f1d2f82 | 1292 | struct trace_event_file *file) |
7862ad18 TZ |
1293 | { |
1294 | struct enable_trigger_data *enable_data = data->private_data; | |
1295 | struct enable_trigger_data *test_enable_data; | |
1296 | struct event_trigger_data *test; | |
1297 | int ret = 0; | |
1298 | ||
1299 | list_for_each_entry_rcu(test, &file->triggers, list) { | |
1300 | test_enable_data = test->private_data; | |
1301 | if (test_enable_data && | |
1302 | (test_enable_data->file == enable_data->file)) { | |
1303 | ret = -EEXIST; | |
1304 | goto out; | |
1305 | } | |
1306 | } | |
1307 | ||
1308 | if (data->ops->init) { | |
1309 | ret = data->ops->init(data->ops, data); | |
1310 | if (ret < 0) | |
1311 | goto out; | |
1312 | } | |
1313 | ||
1314 | list_add_rcu(&data->list, &file->triggers); | |
1315 | ret++; | |
1316 | ||
1317 | if (trace_event_trigger_enable_disable(file, 1) < 0) { | |
1318 | list_del_rcu(&data->list); | |
1319 | ret--; | |
1320 | } | |
bac5fb97 | 1321 | update_cond_flag(file); |
7862ad18 TZ |
1322 | out: |
1323 | return ret; | |
1324 | } | |
1325 | ||
1326 | static void event_enable_unregister_trigger(char *glob, | |
1327 | struct event_trigger_ops *ops, | |
1328 | struct event_trigger_data *test, | |
7f1d2f82 | 1329 | struct trace_event_file *file) |
7862ad18 TZ |
1330 | { |
1331 | struct enable_trigger_data *test_enable_data = test->private_data; | |
1332 | struct enable_trigger_data *enable_data; | |
1333 | struct event_trigger_data *data; | |
1334 | bool unregistered = false; | |
1335 | ||
1336 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
1337 | enable_data = data->private_data; | |
1338 | if (enable_data && | |
1339 | (enable_data->file == test_enable_data->file)) { | |
1340 | unregistered = true; | |
1341 | list_del_rcu(&data->list); | |
bac5fb97 | 1342 | update_cond_flag(file); |
7862ad18 TZ |
1343 | trace_event_trigger_enable_disable(file, 0); |
1344 | break; | |
1345 | } | |
1346 | } | |
1347 | ||
1348 | if (unregistered && data->ops->free) | |
1349 | data->ops->free(data->ops, data); | |
1350 | } | |
1351 | ||
1352 | static struct event_trigger_ops * | |
1353 | event_enable_get_trigger_ops(char *cmd, char *param) | |
1354 | { | |
1355 | struct event_trigger_ops *ops; | |
1356 | bool enable; | |
1357 | ||
1358 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; | |
1359 | ||
1360 | if (enable) | |
1361 | ops = param ? &event_enable_count_trigger_ops : | |
1362 | &event_enable_trigger_ops; | |
1363 | else | |
1364 | ops = param ? &event_disable_count_trigger_ops : | |
1365 | &event_disable_trigger_ops; | |
1366 | ||
1367 | return ops; | |
1368 | } | |
1369 | ||
1370 | static struct event_command trigger_enable_cmd = { | |
1371 | .name = ENABLE_EVENT_STR, | |
1372 | .trigger_type = ETT_EVENT_ENABLE, | |
1373 | .func = event_enable_trigger_func, | |
1374 | .reg = event_enable_register_trigger, | |
1375 | .unreg = event_enable_unregister_trigger, | |
1376 | .get_trigger_ops = event_enable_get_trigger_ops, | |
bac5fb97 | 1377 | .set_filter = set_trigger_filter, |
7862ad18 TZ |
1378 | }; |
1379 | ||
1380 | static struct event_command trigger_disable_cmd = { | |
1381 | .name = DISABLE_EVENT_STR, | |
1382 | .trigger_type = ETT_EVENT_ENABLE, | |
1383 | .func = event_enable_trigger_func, | |
1384 | .reg = event_enable_register_trigger, | |
1385 | .unreg = event_enable_unregister_trigger, | |
1386 | .get_trigger_ops = event_enable_get_trigger_ops, | |
bac5fb97 | 1387 | .set_filter = set_trigger_filter, |
7862ad18 TZ |
1388 | }; |
1389 | ||
1390 | static __init void unregister_trigger_enable_disable_cmds(void) | |
1391 | { | |
1392 | unregister_event_command(&trigger_enable_cmd); | |
1393 | unregister_event_command(&trigger_disable_cmd); | |
1394 | } | |
1395 | ||
1396 | static __init int register_trigger_enable_disable_cmds(void) | |
1397 | { | |
1398 | int ret; | |
1399 | ||
1400 | ret = register_event_command(&trigger_enable_cmd); | |
1401 | if (WARN_ON(ret < 0)) | |
1402 | return ret; | |
1403 | ret = register_event_command(&trigger_disable_cmd); | |
1404 | if (WARN_ON(ret < 0)) | |
1405 | unregister_trigger_enable_disable_cmds(); | |
1406 | ||
1407 | return ret; | |
1408 | } | |
1409 | ||
2a2df321 TZ |
1410 | static __init int register_trigger_traceon_traceoff_cmds(void) |
1411 | { | |
1412 | int ret; | |
1413 | ||
1414 | ret = register_event_command(&trigger_traceon_cmd); | |
1415 | if (WARN_ON(ret < 0)) | |
1416 | return ret; | |
1417 | ret = register_event_command(&trigger_traceoff_cmd); | |
1418 | if (WARN_ON(ret < 0)) | |
1419 | unregister_trigger_traceon_traceoff_cmds(); | |
1420 | ||
1421 | return ret; | |
1422 | } | |
1423 | ||
85f2b082 TZ |
1424 | __init int register_trigger_cmds(void) |
1425 | { | |
2a2df321 | 1426 | register_trigger_traceon_traceoff_cmds(); |
93e31ffb | 1427 | register_trigger_snapshot_cmd(); |
f21ecbb3 | 1428 | register_trigger_stacktrace_cmd(); |
7862ad18 | 1429 | register_trigger_enable_disable_cmds(); |
2a2df321 | 1430 | |
85f2b082 TZ |
1431 | return 0; |
1432 | } |