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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 | ||
ab4bf008 | 31 | void trigger_data_free(struct event_trigger_data *data) |
2a2df321 | 32 | { |
bac5fb97 TZ |
33 | if (data->cmd_ops->set_filter) |
34 | data->cmd_ops->set_filter(NULL, data, NULL); | |
35 | ||
2a2df321 TZ |
36 | synchronize_sched(); /* make sure current triggers exit before free */ |
37 | kfree(data); | |
38 | } | |
39 | ||
85f2b082 TZ |
40 | /** |
41 | * event_triggers_call - Call triggers associated with a trace event | |
7f1d2f82 | 42 | * @file: The trace_event_file associated with the event |
bac5fb97 | 43 | * @rec: The trace entry for the event, NULL for unconditional invocation |
85f2b082 TZ |
44 | * |
45 | * For each trigger associated with an event, invoke the trigger | |
bac5fb97 TZ |
46 | * function registered with the associated trigger command. If rec is |
47 | * non-NULL, it means that the trigger requires further processing and | |
48 | * shouldn't be unconditionally invoked. If rec is non-NULL and the | |
49 | * trigger has a filter associated with it, rec will checked against | |
50 | * the filter and if the record matches the trigger will be invoked. | |
51 | * If the trigger is a 'post_trigger', meaning it shouldn't be invoked | |
52 | * in any case until the current event is written, the trigger | |
53 | * function isn't invoked but the bit associated with the deferred | |
54 | * trigger is set in the return value. | |
55 | * | |
56 | * Returns an enum event_trigger_type value containing a set bit for | |
57 | * any trigger that should be deferred, ETT_NONE if nothing to defer. | |
85f2b082 TZ |
58 | * |
59 | * Called from tracepoint handlers (with rcu_read_lock_sched() held). | |
60 | * | |
61 | * Return: an enum event_trigger_type value containing a set bit for | |
62 | * any trigger that should be deferred, ETT_NONE if nothing to defer. | |
63 | */ | |
bac5fb97 | 64 | enum event_trigger_type |
7f1d2f82 | 65 | event_triggers_call(struct trace_event_file *file, void *rec) |
85f2b082 TZ |
66 | { |
67 | struct event_trigger_data *data; | |
bac5fb97 | 68 | enum event_trigger_type tt = ETT_NONE; |
d8a30f20 | 69 | struct event_filter *filter; |
85f2b082 TZ |
70 | |
71 | if (list_empty(&file->triggers)) | |
bac5fb97 | 72 | return tt; |
85f2b082 | 73 | |
bac5fb97 | 74 | list_for_each_entry_rcu(data, &file->triggers, list) { |
104f2810 TZ |
75 | if (data->paused) |
76 | continue; | |
bac5fb97 | 77 | if (!rec) { |
c4a59230 | 78 | data->ops->func(data, rec); |
bac5fb97 TZ |
79 | continue; |
80 | } | |
561a4fe8 | 81 | filter = rcu_dereference_sched(data->filter); |
d8a30f20 | 82 | if (filter && !filter_match_preds(filter, rec)) |
bac5fb97 | 83 | continue; |
353206f5 | 84 | if (event_command_post_trigger(data->cmd_ops)) { |
bac5fb97 TZ |
85 | tt |= data->cmd_ops->trigger_type; |
86 | continue; | |
87 | } | |
c4a59230 | 88 | data->ops->func(data, rec); |
bac5fb97 TZ |
89 | } |
90 | return tt; | |
85f2b082 TZ |
91 | } |
92 | EXPORT_SYMBOL_GPL(event_triggers_call); | |
93 | ||
bac5fb97 TZ |
94 | /** |
95 | * event_triggers_post_call - Call 'post_triggers' for a trace event | |
7f1d2f82 | 96 | * @file: The trace_event_file associated with the event |
bac5fb97 | 97 | * @tt: enum event_trigger_type containing a set bit for each trigger to invoke |
c4a59230 | 98 | * @rec: The trace entry for the event |
bac5fb97 TZ |
99 | * |
100 | * For each trigger associated with an event, invoke the trigger | |
101 | * function registered with the associated trigger command, if the | |
102 | * corresponding bit is set in the tt enum passed into this function. | |
103 | * See @event_triggers_call for details on how those bits are set. | |
104 | * | |
105 | * Called from tracepoint handlers (with rcu_read_lock_sched() held). | |
106 | */ | |
107 | void | |
7f1d2f82 | 108 | event_triggers_post_call(struct trace_event_file *file, |
c4a59230 TZ |
109 | enum event_trigger_type tt, |
110 | void *rec) | |
bac5fb97 TZ |
111 | { |
112 | struct event_trigger_data *data; | |
113 | ||
114 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
104f2810 TZ |
115 | if (data->paused) |
116 | continue; | |
bac5fb97 | 117 | if (data->cmd_ops->trigger_type & tt) |
c4a59230 | 118 | data->ops->func(data, rec); |
bac5fb97 TZ |
119 | } |
120 | } | |
121 | EXPORT_SYMBOL_GPL(event_triggers_post_call); | |
122 | ||
dd97b954 SRRH |
123 | #define SHOW_AVAILABLE_TRIGGERS (void *)(1UL) |
124 | ||
85f2b082 TZ |
125 | static void *trigger_next(struct seq_file *m, void *t, loff_t *pos) |
126 | { | |
7f1d2f82 | 127 | struct trace_event_file *event_file = event_file_data(m->private); |
85f2b082 | 128 | |
dd97b954 SRRH |
129 | if (t == SHOW_AVAILABLE_TRIGGERS) |
130 | return NULL; | |
131 | ||
85f2b082 TZ |
132 | return seq_list_next(t, &event_file->triggers, pos); |
133 | } | |
134 | ||
135 | static void *trigger_start(struct seq_file *m, loff_t *pos) | |
136 | { | |
7f1d2f82 | 137 | struct trace_event_file *event_file; |
85f2b082 TZ |
138 | |
139 | /* ->stop() is called even if ->start() fails */ | |
140 | mutex_lock(&event_mutex); | |
141 | event_file = event_file_data(m->private); | |
142 | if (unlikely(!event_file)) | |
143 | return ERR_PTR(-ENODEV); | |
144 | ||
dd97b954 SRRH |
145 | if (list_empty(&event_file->triggers)) |
146 | return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL; | |
147 | ||
85f2b082 TZ |
148 | return seq_list_start(&event_file->triggers, *pos); |
149 | } | |
150 | ||
151 | static void trigger_stop(struct seq_file *m, void *t) | |
152 | { | |
153 | mutex_unlock(&event_mutex); | |
154 | } | |
155 | ||
156 | static int trigger_show(struct seq_file *m, void *v) | |
157 | { | |
158 | struct event_trigger_data *data; | |
dd97b954 SRRH |
159 | struct event_command *p; |
160 | ||
161 | if (v == SHOW_AVAILABLE_TRIGGERS) { | |
162 | seq_puts(m, "# Available triggers:\n"); | |
163 | seq_putc(m, '#'); | |
164 | mutex_lock(&trigger_cmd_mutex); | |
165 | list_for_each_entry_reverse(p, &trigger_commands, list) | |
166 | seq_printf(m, " %s", p->name); | |
167 | seq_putc(m, '\n'); | |
168 | mutex_unlock(&trigger_cmd_mutex); | |
169 | return 0; | |
170 | } | |
85f2b082 TZ |
171 | |
172 | data = list_entry(v, struct event_trigger_data, list); | |
173 | data->ops->print(m, data->ops, data); | |
174 | ||
175 | return 0; | |
176 | } | |
177 | ||
178 | static const struct seq_operations event_triggers_seq_ops = { | |
179 | .start = trigger_start, | |
180 | .next = trigger_next, | |
181 | .stop = trigger_stop, | |
182 | .show = trigger_show, | |
183 | }; | |
184 | ||
185 | static int event_trigger_regex_open(struct inode *inode, struct file *file) | |
186 | { | |
187 | int ret = 0; | |
188 | ||
189 | mutex_lock(&event_mutex); | |
190 | ||
191 | if (unlikely(!event_file_data(file))) { | |
192 | mutex_unlock(&event_mutex); | |
193 | return -ENODEV; | |
194 | } | |
195 | ||
a88e1cfb TZ |
196 | if ((file->f_mode & FMODE_WRITE) && |
197 | (file->f_flags & O_TRUNC)) { | |
198 | struct trace_event_file *event_file; | |
199 | struct event_command *p; | |
200 | ||
201 | event_file = event_file_data(file); | |
202 | ||
203 | list_for_each_entry(p, &trigger_commands, list) { | |
204 | if (p->unreg_all) | |
205 | p->unreg_all(event_file); | |
206 | } | |
207 | } | |
208 | ||
85f2b082 TZ |
209 | if (file->f_mode & FMODE_READ) { |
210 | ret = seq_open(file, &event_triggers_seq_ops); | |
211 | if (!ret) { | |
212 | struct seq_file *m = file->private_data; | |
213 | m->private = file; | |
214 | } | |
215 | } | |
216 | ||
217 | mutex_unlock(&event_mutex); | |
218 | ||
219 | return ret; | |
220 | } | |
221 | ||
7f1d2f82 | 222 | static int trigger_process_regex(struct trace_event_file *file, char *buff) |
85f2b082 TZ |
223 | { |
224 | char *command, *next = buff; | |
225 | struct event_command *p; | |
226 | int ret = -EINVAL; | |
227 | ||
228 | command = strsep(&next, ": \t"); | |
229 | command = (command[0] != '!') ? command : command + 1; | |
230 | ||
231 | mutex_lock(&trigger_cmd_mutex); | |
232 | list_for_each_entry(p, &trigger_commands, list) { | |
233 | if (strcmp(p->name, command) == 0) { | |
234 | ret = p->func(p, file, buff, command, next); | |
235 | goto out_unlock; | |
236 | } | |
237 | } | |
238 | out_unlock: | |
239 | mutex_unlock(&trigger_cmd_mutex); | |
240 | ||
241 | return ret; | |
242 | } | |
243 | ||
244 | static ssize_t event_trigger_regex_write(struct file *file, | |
245 | const char __user *ubuf, | |
246 | size_t cnt, loff_t *ppos) | |
247 | { | |
7f1d2f82 | 248 | struct trace_event_file *event_file; |
85f2b082 TZ |
249 | ssize_t ret; |
250 | char *buf; | |
251 | ||
252 | if (!cnt) | |
253 | return 0; | |
254 | ||
255 | if (cnt >= PAGE_SIZE) | |
256 | return -EINVAL; | |
257 | ||
70f6cbb6 AV |
258 | buf = memdup_user_nul(ubuf, cnt); |
259 | if (IS_ERR(buf)) | |
260 | return PTR_ERR(buf); | |
85f2b082 | 261 | |
85f2b082 TZ |
262 | strim(buf); |
263 | ||
264 | mutex_lock(&event_mutex); | |
265 | event_file = event_file_data(file); | |
266 | if (unlikely(!event_file)) { | |
267 | mutex_unlock(&event_mutex); | |
70f6cbb6 | 268 | kfree(buf); |
85f2b082 TZ |
269 | return -ENODEV; |
270 | } | |
271 | ret = trigger_process_regex(event_file, buf); | |
272 | mutex_unlock(&event_mutex); | |
273 | ||
70f6cbb6 | 274 | kfree(buf); |
85f2b082 TZ |
275 | if (ret < 0) |
276 | goto out; | |
277 | ||
278 | *ppos += cnt; | |
279 | ret = cnt; | |
280 | out: | |
281 | return ret; | |
282 | } | |
283 | ||
284 | static int event_trigger_regex_release(struct inode *inode, struct file *file) | |
285 | { | |
286 | mutex_lock(&event_mutex); | |
287 | ||
288 | if (file->f_mode & FMODE_READ) | |
289 | seq_release(inode, file); | |
290 | ||
291 | mutex_unlock(&event_mutex); | |
292 | ||
293 | return 0; | |
294 | } | |
295 | ||
296 | static ssize_t | |
297 | event_trigger_write(struct file *filp, const char __user *ubuf, | |
298 | size_t cnt, loff_t *ppos) | |
299 | { | |
300 | return event_trigger_regex_write(filp, ubuf, cnt, ppos); | |
301 | } | |
302 | ||
303 | static int | |
304 | event_trigger_open(struct inode *inode, struct file *filp) | |
305 | { | |
306 | return event_trigger_regex_open(inode, filp); | |
307 | } | |
308 | ||
309 | static int | |
310 | event_trigger_release(struct inode *inode, struct file *file) | |
311 | { | |
312 | return event_trigger_regex_release(inode, file); | |
313 | } | |
314 | ||
315 | const struct file_operations event_trigger_fops = { | |
316 | .open = event_trigger_open, | |
317 | .read = seq_read, | |
318 | .write = event_trigger_write, | |
098c879e | 319 | .llseek = tracing_lseek, |
85f2b082 TZ |
320 | .release = event_trigger_release, |
321 | }; | |
322 | ||
2a2df321 TZ |
323 | /* |
324 | * Currently we only register event commands from __init, so mark this | |
325 | * __init too. | |
326 | */ | |
ab4bf008 | 327 | __init int register_event_command(struct event_command *cmd) |
2a2df321 TZ |
328 | { |
329 | struct event_command *p; | |
330 | int ret = 0; | |
331 | ||
332 | mutex_lock(&trigger_cmd_mutex); | |
333 | list_for_each_entry(p, &trigger_commands, list) { | |
334 | if (strcmp(cmd->name, p->name) == 0) { | |
335 | ret = -EBUSY; | |
336 | goto out_unlock; | |
337 | } | |
338 | } | |
339 | list_add(&cmd->list, &trigger_commands); | |
340 | out_unlock: | |
341 | mutex_unlock(&trigger_cmd_mutex); | |
342 | ||
343 | return ret; | |
344 | } | |
345 | ||
346 | /* | |
347 | * Currently we only unregister event commands from __init, so mark | |
348 | * this __init too. | |
349 | */ | |
350 | static __init int unregister_event_command(struct event_command *cmd) | |
351 | { | |
352 | struct event_command *p, *n; | |
353 | int ret = -ENODEV; | |
354 | ||
355 | mutex_lock(&trigger_cmd_mutex); | |
356 | list_for_each_entry_safe(p, n, &trigger_commands, list) { | |
357 | if (strcmp(cmd->name, p->name) == 0) { | |
358 | ret = 0; | |
359 | list_del_init(&p->list); | |
360 | goto out_unlock; | |
361 | } | |
362 | } | |
363 | out_unlock: | |
364 | mutex_unlock(&trigger_cmd_mutex); | |
365 | ||
366 | return ret; | |
367 | } | |
368 | ||
369 | /** | |
370 | * event_trigger_print - Generic event_trigger_ops @print implementation | |
371 | * @name: The name of the event trigger | |
372 | * @m: The seq_file being printed to | |
373 | * @data: Trigger-specific data | |
374 | * @filter_str: filter_str to print, if present | |
375 | * | |
376 | * Common implementation for event triggers to print themselves. | |
377 | * | |
378 | * Usually wrapped by a function that simply sets the @name of the | |
379 | * trigger command and then invokes this. | |
380 | * | |
381 | * Return: 0 on success, errno otherwise | |
382 | */ | |
383 | static int | |
384 | event_trigger_print(const char *name, struct seq_file *m, | |
385 | void *data, char *filter_str) | |
386 | { | |
387 | long count = (long)data; | |
388 | ||
fa6f0cc7 | 389 | seq_puts(m, name); |
2a2df321 TZ |
390 | |
391 | if (count == -1) | |
392 | seq_puts(m, ":unlimited"); | |
393 | else | |
394 | seq_printf(m, ":count=%ld", count); | |
395 | ||
396 | if (filter_str) | |
397 | seq_printf(m, " if %s\n", filter_str); | |
398 | else | |
1177e436 | 399 | seq_putc(m, '\n'); |
2a2df321 TZ |
400 | |
401 | return 0; | |
402 | } | |
403 | ||
404 | /** | |
405 | * event_trigger_init - Generic event_trigger_ops @init implementation | |
406 | * @ops: The trigger ops associated with the trigger | |
407 | * @data: Trigger-specific data | |
408 | * | |
409 | * Common implementation of event trigger initialization. | |
410 | * | |
411 | * Usually used directly as the @init method in event trigger | |
412 | * implementations. | |
413 | * | |
414 | * Return: 0 on success, errno otherwise | |
415 | */ | |
ab4bf008 TZ |
416 | int event_trigger_init(struct event_trigger_ops *ops, |
417 | struct event_trigger_data *data) | |
2a2df321 TZ |
418 | { |
419 | data->ref++; | |
420 | return 0; | |
421 | } | |
422 | ||
423 | /** | |
424 | * event_trigger_free - Generic event_trigger_ops @free implementation | |
425 | * @ops: The trigger ops associated with the trigger | |
426 | * @data: Trigger-specific data | |
427 | * | |
428 | * Common implementation of event trigger de-initialization. | |
429 | * | |
430 | * Usually used directly as the @free method in event trigger | |
431 | * implementations. | |
432 | */ | |
433 | static void | |
434 | event_trigger_free(struct event_trigger_ops *ops, | |
435 | struct event_trigger_data *data) | |
436 | { | |
437 | if (WARN_ON_ONCE(data->ref <= 0)) | |
438 | return; | |
439 | ||
440 | data->ref--; | |
441 | if (!data->ref) | |
442 | trigger_data_free(data); | |
443 | } | |
444 | ||
ab4bf008 TZ |
445 | int trace_event_trigger_enable_disable(struct trace_event_file *file, |
446 | int trigger_enable) | |
85f2b082 TZ |
447 | { |
448 | int ret = 0; | |
449 | ||
450 | if (trigger_enable) { | |
451 | if (atomic_inc_return(&file->tm_ref) > 1) | |
452 | return ret; | |
5d6ad960 | 453 | set_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags); |
85f2b082 TZ |
454 | ret = trace_event_enable_disable(file, 1, 1); |
455 | } else { | |
456 | if (atomic_dec_return(&file->tm_ref) > 0) | |
457 | return ret; | |
5d6ad960 | 458 | clear_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags); |
85f2b082 TZ |
459 | ret = trace_event_enable_disable(file, 0, 1); |
460 | } | |
461 | ||
462 | return ret; | |
463 | } | |
464 | ||
465 | /** | |
466 | * clear_event_triggers - Clear all triggers associated with a trace array | |
467 | * @tr: The trace array to clear | |
468 | * | |
469 | * For each trigger, the triggering event has its tm_ref decremented | |
470 | * via trace_event_trigger_enable_disable(), and any associated event | |
471 | * (in the case of enable/disable_event triggers) will have its sm_ref | |
472 | * decremented via free()->trace_event_enable_disable(). That | |
473 | * combination effectively reverses the soft-mode/trigger state added | |
474 | * by trigger registration. | |
475 | * | |
476 | * Must be called with event_mutex held. | |
477 | */ | |
478 | void | |
479 | clear_event_triggers(struct trace_array *tr) | |
480 | { | |
7f1d2f82 | 481 | struct trace_event_file *file; |
85f2b082 TZ |
482 | |
483 | list_for_each_entry(file, &tr->events, list) { | |
484 | struct event_trigger_data *data; | |
485 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
486 | trace_event_trigger_enable_disable(file, 0); | |
487 | if (data->ops->free) | |
488 | data->ops->free(data->ops, data); | |
489 | } | |
490 | } | |
491 | } | |
492 | ||
bac5fb97 TZ |
493 | /** |
494 | * update_cond_flag - Set or reset the TRIGGER_COND bit | |
7f1d2f82 | 495 | * @file: The trace_event_file associated with the event |
bac5fb97 TZ |
496 | * |
497 | * If an event has triggers and any of those triggers has a filter or | |
498 | * a post_trigger, trigger invocation needs to be deferred until after | |
499 | * the current event has logged its data, and the event should have | |
500 | * its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be | |
501 | * cleared. | |
502 | */ | |
ab4bf008 | 503 | void update_cond_flag(struct trace_event_file *file) |
bac5fb97 TZ |
504 | { |
505 | struct event_trigger_data *data; | |
506 | bool set_cond = false; | |
507 | ||
508 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
353206f5 SRRH |
509 | if (data->filter || event_command_post_trigger(data->cmd_ops) || |
510 | event_command_needs_rec(data->cmd_ops)) { | |
bac5fb97 TZ |
511 | set_cond = true; |
512 | break; | |
513 | } | |
514 | } | |
515 | ||
516 | if (set_cond) | |
5d6ad960 | 517 | set_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags); |
bac5fb97 | 518 | else |
5d6ad960 | 519 | clear_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags); |
bac5fb97 TZ |
520 | } |
521 | ||
2a2df321 TZ |
522 | /** |
523 | * register_trigger - Generic event_command @reg implementation | |
524 | * @glob: The raw string used to register the trigger | |
525 | * @ops: The trigger ops associated with the trigger | |
526 | * @data: Trigger-specific data to associate with the trigger | |
7f1d2f82 | 527 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
528 | * |
529 | * Common implementation for event trigger registration. | |
530 | * | |
531 | * Usually used directly as the @reg method in event command | |
532 | * implementations. | |
533 | * | |
534 | * Return: 0 on success, errno otherwise | |
535 | */ | |
536 | static int register_trigger(char *glob, struct event_trigger_ops *ops, | |
537 | struct event_trigger_data *data, | |
7f1d2f82 | 538 | struct trace_event_file *file) |
2a2df321 TZ |
539 | { |
540 | struct event_trigger_data *test; | |
541 | int ret = 0; | |
542 | ||
543 | list_for_each_entry_rcu(test, &file->triggers, list) { | |
544 | if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) { | |
545 | ret = -EEXIST; | |
546 | goto out; | |
547 | } | |
548 | } | |
549 | ||
550 | if (data->ops->init) { | |
551 | ret = data->ops->init(data->ops, data); | |
552 | if (ret < 0) | |
553 | goto out; | |
554 | } | |
555 | ||
556 | list_add_rcu(&data->list, &file->triggers); | |
557 | ret++; | |
558 | ||
4e4a4d75 | 559 | update_cond_flag(file); |
2a2df321 TZ |
560 | if (trace_event_trigger_enable_disable(file, 1) < 0) { |
561 | list_del_rcu(&data->list); | |
4e4a4d75 | 562 | update_cond_flag(file); |
2a2df321 TZ |
563 | ret--; |
564 | } | |
565 | out: | |
566 | return ret; | |
567 | } | |
568 | ||
569 | /** | |
570 | * unregister_trigger - Generic event_command @unreg implementation | |
571 | * @glob: The raw string used to register the trigger | |
572 | * @ops: The trigger ops associated with the trigger | |
573 | * @test: Trigger-specific data used to find the trigger to remove | |
7f1d2f82 | 574 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
575 | * |
576 | * Common implementation for event trigger unregistration. | |
577 | * | |
578 | * Usually used directly as the @unreg method in event command | |
579 | * implementations. | |
580 | */ | |
ab4bf008 TZ |
581 | void unregister_trigger(char *glob, struct event_trigger_ops *ops, |
582 | struct event_trigger_data *test, | |
583 | struct trace_event_file *file) | |
2a2df321 TZ |
584 | { |
585 | struct event_trigger_data *data; | |
586 | bool unregistered = false; | |
587 | ||
588 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
589 | if (data->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { | |
590 | unregistered = true; | |
591 | list_del_rcu(&data->list); | |
592 | trace_event_trigger_enable_disable(file, 0); | |
4e4a4d75 | 593 | update_cond_flag(file); |
2a2df321 TZ |
594 | break; |
595 | } | |
596 | } | |
597 | ||
598 | if (unregistered && data->ops->free) | |
599 | data->ops->free(data->ops, data); | |
600 | } | |
601 | ||
602 | /** | |
603 | * event_trigger_callback - Generic event_command @func implementation | |
604 | * @cmd_ops: The command ops, used for trigger registration | |
7f1d2f82 | 605 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
606 | * @glob: The raw string used to register the trigger |
607 | * @cmd: The cmd portion of the string used to register the trigger | |
608 | * @param: The params portion of the string used to register the trigger | |
609 | * | |
610 | * Common implementation for event command parsing and trigger | |
611 | * instantiation. | |
612 | * | |
613 | * Usually used directly as the @func method in event command | |
614 | * implementations. | |
615 | * | |
616 | * Return: 0 on success, errno otherwise | |
617 | */ | |
618 | static int | |
619 | event_trigger_callback(struct event_command *cmd_ops, | |
7f1d2f82 | 620 | struct trace_event_file *file, |
2a2df321 TZ |
621 | char *glob, char *cmd, char *param) |
622 | { | |
623 | struct event_trigger_data *trigger_data; | |
624 | struct event_trigger_ops *trigger_ops; | |
625 | char *trigger = NULL; | |
626 | char *number; | |
627 | int ret; | |
628 | ||
629 | /* separate the trigger from the filter (t:n [if filter]) */ | |
630 | if (param && isdigit(param[0])) | |
631 | trigger = strsep(¶m, " \t"); | |
632 | ||
633 | trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); | |
634 | ||
635 | ret = -ENOMEM; | |
636 | trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); | |
637 | if (!trigger_data) | |
638 | goto out; | |
639 | ||
640 | trigger_data->count = -1; | |
641 | trigger_data->ops = trigger_ops; | |
642 | trigger_data->cmd_ops = cmd_ops; | |
643 | INIT_LIST_HEAD(&trigger_data->list); | |
644 | ||
645 | if (glob[0] == '!') { | |
646 | cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); | |
647 | kfree(trigger_data); | |
648 | ret = 0; | |
649 | goto out; | |
650 | } | |
651 | ||
652 | if (trigger) { | |
653 | number = strsep(&trigger, ":"); | |
654 | ||
655 | ret = -EINVAL; | |
656 | if (!strlen(number)) | |
657 | goto out_free; | |
658 | ||
659 | /* | |
660 | * We use the callback data field (which is a pointer) | |
661 | * as our counter. | |
662 | */ | |
663 | ret = kstrtoul(number, 0, &trigger_data->count); | |
664 | if (ret) | |
665 | goto out_free; | |
666 | } | |
667 | ||
668 | if (!param) /* if param is non-empty, it's supposed to be a filter */ | |
669 | goto out_reg; | |
670 | ||
671 | if (!cmd_ops->set_filter) | |
672 | goto out_reg; | |
673 | ||
674 | ret = cmd_ops->set_filter(param, trigger_data, file); | |
675 | if (ret < 0) | |
676 | goto out_free; | |
677 | ||
678 | out_reg: | |
679 | ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); | |
680 | /* | |
681 | * The above returns on success the # of functions enabled, | |
682 | * but if it didn't find any functions it returns zero. | |
683 | * Consider no functions a failure too. | |
684 | */ | |
685 | if (!ret) { | |
686 | ret = -ENOENT; | |
687 | goto out_free; | |
688 | } else if (ret < 0) | |
689 | goto out_free; | |
690 | ret = 0; | |
691 | out: | |
692 | return ret; | |
693 | ||
694 | out_free: | |
bac5fb97 TZ |
695 | if (cmd_ops->set_filter) |
696 | cmd_ops->set_filter(NULL, trigger_data, NULL); | |
2a2df321 TZ |
697 | kfree(trigger_data); |
698 | goto out; | |
699 | } | |
700 | ||
bac5fb97 TZ |
701 | /** |
702 | * set_trigger_filter - Generic event_command @set_filter implementation | |
703 | * @filter_str: The filter string for the trigger, NULL to remove filter | |
704 | * @trigger_data: Trigger-specific data | |
7f1d2f82 | 705 | * @file: The trace_event_file associated with the event |
bac5fb97 TZ |
706 | * |
707 | * Common implementation for event command filter parsing and filter | |
708 | * instantiation. | |
709 | * | |
710 | * Usually used directly as the @set_filter method in event command | |
711 | * implementations. | |
712 | * | |
713 | * Also used to remove a filter (if filter_str = NULL). | |
714 | * | |
715 | * Return: 0 on success, errno otherwise | |
716 | */ | |
ab4bf008 TZ |
717 | int set_trigger_filter(char *filter_str, |
718 | struct event_trigger_data *trigger_data, | |
719 | struct trace_event_file *file) | |
bac5fb97 TZ |
720 | { |
721 | struct event_trigger_data *data = trigger_data; | |
722 | struct event_filter *filter = NULL, *tmp; | |
723 | int ret = -EINVAL; | |
724 | char *s; | |
725 | ||
726 | if (!filter_str) /* clear the current filter */ | |
727 | goto assign; | |
728 | ||
729 | s = strsep(&filter_str, " \t"); | |
730 | ||
731 | if (!strlen(s) || strcmp(s, "if") != 0) | |
732 | goto out; | |
733 | ||
734 | if (!filter_str) | |
735 | goto out; | |
736 | ||
737 | /* The filter is for the 'trigger' event, not the triggered event */ | |
738 | ret = create_event_filter(file->event_call, filter_str, false, &filter); | |
739 | if (ret) | |
740 | goto out; | |
741 | assign: | |
d8a30f20 | 742 | tmp = rcu_access_pointer(data->filter); |
bac5fb97 TZ |
743 | |
744 | rcu_assign_pointer(data->filter, filter); | |
745 | ||
746 | if (tmp) { | |
747 | /* Make sure the call is done with the filter */ | |
748 | synchronize_sched(); | |
749 | free_event_filter(tmp); | |
750 | } | |
751 | ||
752 | kfree(data->filter_str); | |
753 | data->filter_str = NULL; | |
754 | ||
755 | if (filter_str) { | |
756 | data->filter_str = kstrdup(filter_str, GFP_KERNEL); | |
757 | if (!data->filter_str) { | |
d8a30f20 | 758 | free_event_filter(rcu_access_pointer(data->filter)); |
bac5fb97 TZ |
759 | data->filter = NULL; |
760 | ret = -ENOMEM; | |
761 | } | |
762 | } | |
763 | out: | |
764 | return ret; | |
765 | } | |
766 | ||
2a2df321 | 767 | static void |
c4a59230 | 768 | traceon_trigger(struct event_trigger_data *data, void *rec) |
2a2df321 TZ |
769 | { |
770 | if (tracing_is_on()) | |
771 | return; | |
772 | ||
773 | tracing_on(); | |
774 | } | |
775 | ||
776 | static void | |
c4a59230 | 777 | traceon_count_trigger(struct event_trigger_data *data, void *rec) |
2a2df321 | 778 | { |
e8dc6371 SRRH |
779 | if (tracing_is_on()) |
780 | return; | |
781 | ||
2a2df321 TZ |
782 | if (!data->count) |
783 | return; | |
784 | ||
785 | if (data->count != -1) | |
786 | (data->count)--; | |
787 | ||
e8dc6371 | 788 | tracing_on(); |
2a2df321 TZ |
789 | } |
790 | ||
791 | static void | |
c4a59230 | 792 | traceoff_trigger(struct event_trigger_data *data, void *rec) |
2a2df321 TZ |
793 | { |
794 | if (!tracing_is_on()) | |
795 | return; | |
796 | ||
797 | tracing_off(); | |
798 | } | |
799 | ||
800 | static void | |
c4a59230 | 801 | traceoff_count_trigger(struct event_trigger_data *data, void *rec) |
2a2df321 | 802 | { |
e8dc6371 SRRH |
803 | if (!tracing_is_on()) |
804 | return; | |
805 | ||
2a2df321 TZ |
806 | if (!data->count) |
807 | return; | |
808 | ||
809 | if (data->count != -1) | |
810 | (data->count)--; | |
811 | ||
e8dc6371 | 812 | tracing_off(); |
2a2df321 TZ |
813 | } |
814 | ||
815 | static int | |
816 | traceon_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
817 | struct event_trigger_data *data) | |
818 | { | |
819 | return event_trigger_print("traceon", m, (void *)data->count, | |
820 | data->filter_str); | |
821 | } | |
822 | ||
823 | static int | |
824 | traceoff_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
825 | struct event_trigger_data *data) | |
826 | { | |
827 | return event_trigger_print("traceoff", m, (void *)data->count, | |
828 | data->filter_str); | |
829 | } | |
830 | ||
831 | static struct event_trigger_ops traceon_trigger_ops = { | |
832 | .func = traceon_trigger, | |
833 | .print = traceon_trigger_print, | |
834 | .init = event_trigger_init, | |
835 | .free = event_trigger_free, | |
836 | }; | |
837 | ||
838 | static struct event_trigger_ops traceon_count_trigger_ops = { | |
839 | .func = traceon_count_trigger, | |
840 | .print = traceon_trigger_print, | |
841 | .init = event_trigger_init, | |
842 | .free = event_trigger_free, | |
843 | }; | |
844 | ||
845 | static struct event_trigger_ops traceoff_trigger_ops = { | |
846 | .func = traceoff_trigger, | |
847 | .print = traceoff_trigger_print, | |
848 | .init = event_trigger_init, | |
849 | .free = event_trigger_free, | |
850 | }; | |
851 | ||
852 | static struct event_trigger_ops traceoff_count_trigger_ops = { | |
853 | .func = traceoff_count_trigger, | |
854 | .print = traceoff_trigger_print, | |
855 | .init = event_trigger_init, | |
856 | .free = event_trigger_free, | |
857 | }; | |
858 | ||
859 | static struct event_trigger_ops * | |
860 | onoff_get_trigger_ops(char *cmd, char *param) | |
861 | { | |
862 | struct event_trigger_ops *ops; | |
863 | ||
864 | /* we register both traceon and traceoff to this callback */ | |
865 | if (strcmp(cmd, "traceon") == 0) | |
866 | ops = param ? &traceon_count_trigger_ops : | |
867 | &traceon_trigger_ops; | |
868 | else | |
869 | ops = param ? &traceoff_count_trigger_ops : | |
870 | &traceoff_trigger_ops; | |
871 | ||
872 | return ops; | |
873 | } | |
874 | ||
875 | static struct event_command trigger_traceon_cmd = { | |
876 | .name = "traceon", | |
877 | .trigger_type = ETT_TRACE_ONOFF, | |
878 | .func = event_trigger_callback, | |
879 | .reg = register_trigger, | |
880 | .unreg = unregister_trigger, | |
881 | .get_trigger_ops = onoff_get_trigger_ops, | |
bac5fb97 | 882 | .set_filter = set_trigger_filter, |
2a2df321 TZ |
883 | }; |
884 | ||
885 | static struct event_command trigger_traceoff_cmd = { | |
886 | .name = "traceoff", | |
887 | .trigger_type = ETT_TRACE_ONOFF, | |
888 | .func = event_trigger_callback, | |
889 | .reg = register_trigger, | |
890 | .unreg = unregister_trigger, | |
891 | .get_trigger_ops = onoff_get_trigger_ops, | |
bac5fb97 | 892 | .set_filter = set_trigger_filter, |
2a2df321 TZ |
893 | }; |
894 | ||
93e31ffb TZ |
895 | #ifdef CONFIG_TRACER_SNAPSHOT |
896 | static void | |
c4a59230 | 897 | snapshot_trigger(struct event_trigger_data *data, void *rec) |
93e31ffb TZ |
898 | { |
899 | tracing_snapshot(); | |
900 | } | |
901 | ||
902 | static void | |
c4a59230 | 903 | snapshot_count_trigger(struct event_trigger_data *data, void *rec) |
93e31ffb TZ |
904 | { |
905 | if (!data->count) | |
906 | return; | |
907 | ||
908 | if (data->count != -1) | |
909 | (data->count)--; | |
910 | ||
c4a59230 | 911 | snapshot_trigger(data, rec); |
93e31ffb TZ |
912 | } |
913 | ||
914 | static int | |
915 | register_snapshot_trigger(char *glob, struct event_trigger_ops *ops, | |
916 | struct event_trigger_data *data, | |
7f1d2f82 | 917 | struct trace_event_file *file) |
93e31ffb TZ |
918 | { |
919 | int ret = register_trigger(glob, ops, data, file); | |
920 | ||
921 | if (ret > 0 && tracing_alloc_snapshot() != 0) { | |
922 | unregister_trigger(glob, ops, data, file); | |
923 | ret = 0; | |
924 | } | |
925 | ||
926 | return ret; | |
927 | } | |
928 | ||
929 | static int | |
930 | snapshot_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
931 | struct event_trigger_data *data) | |
932 | { | |
933 | return event_trigger_print("snapshot", m, (void *)data->count, | |
934 | data->filter_str); | |
935 | } | |
936 | ||
937 | static struct event_trigger_ops snapshot_trigger_ops = { | |
938 | .func = snapshot_trigger, | |
939 | .print = snapshot_trigger_print, | |
940 | .init = event_trigger_init, | |
941 | .free = event_trigger_free, | |
942 | }; | |
943 | ||
944 | static struct event_trigger_ops snapshot_count_trigger_ops = { | |
945 | .func = snapshot_count_trigger, | |
946 | .print = snapshot_trigger_print, | |
947 | .init = event_trigger_init, | |
948 | .free = event_trigger_free, | |
949 | }; | |
950 | ||
951 | static struct event_trigger_ops * | |
952 | snapshot_get_trigger_ops(char *cmd, char *param) | |
953 | { | |
954 | return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops; | |
955 | } | |
956 | ||
957 | static struct event_command trigger_snapshot_cmd = { | |
958 | .name = "snapshot", | |
959 | .trigger_type = ETT_SNAPSHOT, | |
960 | .func = event_trigger_callback, | |
961 | .reg = register_snapshot_trigger, | |
962 | .unreg = unregister_trigger, | |
963 | .get_trigger_ops = snapshot_get_trigger_ops, | |
bac5fb97 | 964 | .set_filter = set_trigger_filter, |
93e31ffb TZ |
965 | }; |
966 | ||
967 | static __init int register_trigger_snapshot_cmd(void) | |
968 | { | |
969 | int ret; | |
970 | ||
971 | ret = register_event_command(&trigger_snapshot_cmd); | |
972 | WARN_ON(ret < 0); | |
973 | ||
974 | return ret; | |
975 | } | |
976 | #else | |
977 | static __init int register_trigger_snapshot_cmd(void) { return 0; } | |
978 | #endif /* CONFIG_TRACER_SNAPSHOT */ | |
979 | ||
f21ecbb3 TZ |
980 | #ifdef CONFIG_STACKTRACE |
981 | /* | |
982 | * Skip 3: | |
983 | * stacktrace_trigger() | |
984 | * event_triggers_post_call() | |
a7237765 | 985 | * trace_event_raw_event_xxx() |
f21ecbb3 TZ |
986 | */ |
987 | #define STACK_SKIP 3 | |
988 | ||
989 | static void | |
c4a59230 | 990 | stacktrace_trigger(struct event_trigger_data *data, void *rec) |
f21ecbb3 TZ |
991 | { |
992 | trace_dump_stack(STACK_SKIP); | |
993 | } | |
994 | ||
995 | static void | |
c4a59230 | 996 | stacktrace_count_trigger(struct event_trigger_data *data, void *rec) |
f21ecbb3 TZ |
997 | { |
998 | if (!data->count) | |
999 | return; | |
1000 | ||
1001 | if (data->count != -1) | |
1002 | (data->count)--; | |
1003 | ||
c4a59230 | 1004 | stacktrace_trigger(data, rec); |
f21ecbb3 TZ |
1005 | } |
1006 | ||
1007 | static int | |
1008 | stacktrace_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
1009 | struct event_trigger_data *data) | |
1010 | { | |
1011 | return event_trigger_print("stacktrace", m, (void *)data->count, | |
1012 | data->filter_str); | |
1013 | } | |
1014 | ||
1015 | static struct event_trigger_ops stacktrace_trigger_ops = { | |
1016 | .func = stacktrace_trigger, | |
1017 | .print = stacktrace_trigger_print, | |
1018 | .init = event_trigger_init, | |
1019 | .free = event_trigger_free, | |
1020 | }; | |
1021 | ||
1022 | static struct event_trigger_ops stacktrace_count_trigger_ops = { | |
1023 | .func = stacktrace_count_trigger, | |
1024 | .print = stacktrace_trigger_print, | |
1025 | .init = event_trigger_init, | |
1026 | .free = event_trigger_free, | |
1027 | }; | |
1028 | ||
1029 | static struct event_trigger_ops * | |
1030 | stacktrace_get_trigger_ops(char *cmd, char *param) | |
1031 | { | |
1032 | return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops; | |
1033 | } | |
1034 | ||
1035 | static struct event_command trigger_stacktrace_cmd = { | |
1036 | .name = "stacktrace", | |
1037 | .trigger_type = ETT_STACKTRACE, | |
353206f5 | 1038 | .flags = EVENT_CMD_FL_POST_TRIGGER, |
f21ecbb3 TZ |
1039 | .func = event_trigger_callback, |
1040 | .reg = register_trigger, | |
1041 | .unreg = unregister_trigger, | |
1042 | .get_trigger_ops = stacktrace_get_trigger_ops, | |
bac5fb97 | 1043 | .set_filter = set_trigger_filter, |
f21ecbb3 TZ |
1044 | }; |
1045 | ||
1046 | static __init int register_trigger_stacktrace_cmd(void) | |
1047 | { | |
1048 | int ret; | |
1049 | ||
1050 | ret = register_event_command(&trigger_stacktrace_cmd); | |
1051 | WARN_ON(ret < 0); | |
1052 | ||
1053 | return ret; | |
1054 | } | |
1055 | #else | |
1056 | static __init int register_trigger_stacktrace_cmd(void) { return 0; } | |
1057 | #endif /* CONFIG_STACKTRACE */ | |
1058 | ||
2a2df321 TZ |
1059 | static __init void unregister_trigger_traceon_traceoff_cmds(void) |
1060 | { | |
1061 | unregister_event_command(&trigger_traceon_cmd); | |
1062 | unregister_event_command(&trigger_traceoff_cmd); | |
1063 | } | |
1064 | ||
7862ad18 TZ |
1065 | /* Avoid typos */ |
1066 | #define ENABLE_EVENT_STR "enable_event" | |
1067 | #define DISABLE_EVENT_STR "disable_event" | |
1068 | ||
1069 | struct enable_trigger_data { | |
7f1d2f82 | 1070 | struct trace_event_file *file; |
7862ad18 TZ |
1071 | bool enable; |
1072 | }; | |
1073 | ||
1074 | static void | |
c4a59230 | 1075 | event_enable_trigger(struct event_trigger_data *data, void *rec) |
7862ad18 TZ |
1076 | { |
1077 | struct enable_trigger_data *enable_data = data->private_data; | |
1078 | ||
1079 | if (enable_data->enable) | |
5d6ad960 | 1080 | clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); |
7862ad18 | 1081 | else |
5d6ad960 | 1082 | set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); |
7862ad18 TZ |
1083 | } |
1084 | ||
1085 | static void | |
c4a59230 | 1086 | event_enable_count_trigger(struct event_trigger_data *data, void *rec) |
7862ad18 TZ |
1087 | { |
1088 | struct enable_trigger_data *enable_data = data->private_data; | |
1089 | ||
1090 | if (!data->count) | |
1091 | return; | |
1092 | ||
1093 | /* Skip if the event is in a state we want to switch to */ | |
5d6ad960 | 1094 | if (enable_data->enable == !(enable_data->file->flags & EVENT_FILE_FL_SOFT_DISABLED)) |
7862ad18 TZ |
1095 | return; |
1096 | ||
1097 | if (data->count != -1) | |
1098 | (data->count)--; | |
1099 | ||
c4a59230 | 1100 | event_enable_trigger(data, rec); |
7862ad18 TZ |
1101 | } |
1102 | ||
1103 | static int | |
1104 | event_enable_trigger_print(struct seq_file *m, struct event_trigger_ops *ops, | |
1105 | struct event_trigger_data *data) | |
1106 | { | |
1107 | struct enable_trigger_data *enable_data = data->private_data; | |
1108 | ||
1109 | seq_printf(m, "%s:%s:%s", | |
1110 | enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR, | |
1111 | enable_data->file->event_call->class->system, | |
687fcc4a | 1112 | trace_event_name(enable_data->file->event_call)); |
7862ad18 TZ |
1113 | |
1114 | if (data->count == -1) | |
1115 | seq_puts(m, ":unlimited"); | |
1116 | else | |
1117 | seq_printf(m, ":count=%ld", data->count); | |
1118 | ||
1119 | if (data->filter_str) | |
1120 | seq_printf(m, " if %s\n", data->filter_str); | |
1121 | else | |
1177e436 | 1122 | seq_putc(m, '\n'); |
7862ad18 TZ |
1123 | |
1124 | return 0; | |
1125 | } | |
1126 | ||
1127 | static void | |
1128 | event_enable_trigger_free(struct event_trigger_ops *ops, | |
1129 | struct event_trigger_data *data) | |
1130 | { | |
1131 | struct enable_trigger_data *enable_data = data->private_data; | |
1132 | ||
1133 | if (WARN_ON_ONCE(data->ref <= 0)) | |
1134 | return; | |
1135 | ||
1136 | data->ref--; | |
1137 | if (!data->ref) { | |
1138 | /* Remove the SOFT_MODE flag */ | |
1139 | trace_event_enable_disable(enable_data->file, 0, 1); | |
1140 | module_put(enable_data->file->event_call->mod); | |
1141 | trigger_data_free(data); | |
1142 | kfree(enable_data); | |
1143 | } | |
1144 | } | |
1145 | ||
1146 | static struct event_trigger_ops event_enable_trigger_ops = { | |
1147 | .func = event_enable_trigger, | |
1148 | .print = event_enable_trigger_print, | |
1149 | .init = event_trigger_init, | |
1150 | .free = event_enable_trigger_free, | |
1151 | }; | |
1152 | ||
1153 | static struct event_trigger_ops event_enable_count_trigger_ops = { | |
1154 | .func = event_enable_count_trigger, | |
1155 | .print = event_enable_trigger_print, | |
1156 | .init = event_trigger_init, | |
1157 | .free = event_enable_trigger_free, | |
1158 | }; | |
1159 | ||
1160 | static struct event_trigger_ops event_disable_trigger_ops = { | |
1161 | .func = event_enable_trigger, | |
1162 | .print = event_enable_trigger_print, | |
1163 | .init = event_trigger_init, | |
1164 | .free = event_enable_trigger_free, | |
1165 | }; | |
1166 | ||
1167 | static struct event_trigger_ops event_disable_count_trigger_ops = { | |
1168 | .func = event_enable_count_trigger, | |
1169 | .print = event_enable_trigger_print, | |
1170 | .init = event_trigger_init, | |
1171 | .free = event_enable_trigger_free, | |
1172 | }; | |
1173 | ||
1174 | static int | |
1175 | event_enable_trigger_func(struct event_command *cmd_ops, | |
7f1d2f82 | 1176 | struct trace_event_file *file, |
7862ad18 TZ |
1177 | char *glob, char *cmd, char *param) |
1178 | { | |
7f1d2f82 | 1179 | struct trace_event_file *event_enable_file; |
7862ad18 TZ |
1180 | struct enable_trigger_data *enable_data; |
1181 | struct event_trigger_data *trigger_data; | |
1182 | struct event_trigger_ops *trigger_ops; | |
1183 | struct trace_array *tr = file->tr; | |
1184 | const char *system; | |
1185 | const char *event; | |
1186 | char *trigger; | |
1187 | char *number; | |
1188 | bool enable; | |
1189 | int ret; | |
1190 | ||
1191 | if (!param) | |
1192 | return -EINVAL; | |
1193 | ||
1194 | /* separate the trigger from the filter (s:e:n [if filter]) */ | |
1195 | trigger = strsep(¶m, " \t"); | |
1196 | if (!trigger) | |
1197 | return -EINVAL; | |
1198 | ||
1199 | system = strsep(&trigger, ":"); | |
1200 | if (!trigger) | |
1201 | return -EINVAL; | |
1202 | ||
1203 | event = strsep(&trigger, ":"); | |
1204 | ||
1205 | ret = -EINVAL; | |
1206 | event_enable_file = find_event_file(tr, system, event); | |
1207 | if (!event_enable_file) | |
1208 | goto out; | |
1209 | ||
1210 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; | |
1211 | ||
1212 | trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); | |
1213 | ||
1214 | ret = -ENOMEM; | |
1215 | trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); | |
1216 | if (!trigger_data) | |
1217 | goto out; | |
1218 | ||
1219 | enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL); | |
1220 | if (!enable_data) { | |
1221 | kfree(trigger_data); | |
1222 | goto out; | |
1223 | } | |
1224 | ||
1225 | trigger_data->count = -1; | |
1226 | trigger_data->ops = trigger_ops; | |
1227 | trigger_data->cmd_ops = cmd_ops; | |
1228 | INIT_LIST_HEAD(&trigger_data->list); | |
1229 | RCU_INIT_POINTER(trigger_data->filter, NULL); | |
1230 | ||
1231 | enable_data->enable = enable; | |
1232 | enable_data->file = event_enable_file; | |
1233 | trigger_data->private_data = enable_data; | |
1234 | ||
1235 | if (glob[0] == '!') { | |
1236 | cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); | |
1237 | kfree(trigger_data); | |
1238 | kfree(enable_data); | |
1239 | ret = 0; | |
1240 | goto out; | |
1241 | } | |
1242 | ||
1243 | if (trigger) { | |
1244 | number = strsep(&trigger, ":"); | |
1245 | ||
1246 | ret = -EINVAL; | |
1247 | if (!strlen(number)) | |
1248 | goto out_free; | |
1249 | ||
1250 | /* | |
1251 | * We use the callback data field (which is a pointer) | |
1252 | * as our counter. | |
1253 | */ | |
1254 | ret = kstrtoul(number, 0, &trigger_data->count); | |
1255 | if (ret) | |
1256 | goto out_free; | |
1257 | } | |
1258 | ||
1259 | if (!param) /* if param is non-empty, it's supposed to be a filter */ | |
1260 | goto out_reg; | |
1261 | ||
1262 | if (!cmd_ops->set_filter) | |
1263 | goto out_reg; | |
1264 | ||
1265 | ret = cmd_ops->set_filter(param, trigger_data, file); | |
1266 | if (ret < 0) | |
1267 | goto out_free; | |
1268 | ||
1269 | out_reg: | |
1270 | /* Don't let event modules unload while probe registered */ | |
1271 | ret = try_module_get(event_enable_file->event_call->mod); | |
1272 | if (!ret) { | |
1273 | ret = -EBUSY; | |
1274 | goto out_free; | |
1275 | } | |
1276 | ||
1277 | ret = trace_event_enable_disable(event_enable_file, 1, 1); | |
1278 | if (ret < 0) | |
1279 | goto out_put; | |
1280 | ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); | |
1281 | /* | |
1282 | * The above returns on success the # of functions enabled, | |
1283 | * but if it didn't find any functions it returns zero. | |
1284 | * Consider no functions a failure too. | |
1285 | */ | |
1286 | if (!ret) { | |
1287 | ret = -ENOENT; | |
1288 | goto out_disable; | |
1289 | } else if (ret < 0) | |
1290 | goto out_disable; | |
1291 | /* Just return zero, not the number of enabled functions */ | |
1292 | ret = 0; | |
1293 | out: | |
1294 | return ret; | |
1295 | ||
1296 | out_disable: | |
1297 | trace_event_enable_disable(event_enable_file, 0, 1); | |
1298 | out_put: | |
1299 | module_put(event_enable_file->event_call->mod); | |
1300 | out_free: | |
bac5fb97 TZ |
1301 | if (cmd_ops->set_filter) |
1302 | cmd_ops->set_filter(NULL, trigger_data, NULL); | |
7862ad18 TZ |
1303 | kfree(trigger_data); |
1304 | kfree(enable_data); | |
1305 | goto out; | |
1306 | } | |
1307 | ||
1308 | static int event_enable_register_trigger(char *glob, | |
1309 | struct event_trigger_ops *ops, | |
1310 | struct event_trigger_data *data, | |
7f1d2f82 | 1311 | struct trace_event_file *file) |
7862ad18 TZ |
1312 | { |
1313 | struct enable_trigger_data *enable_data = data->private_data; | |
1314 | struct enable_trigger_data *test_enable_data; | |
1315 | struct event_trigger_data *test; | |
1316 | int ret = 0; | |
1317 | ||
1318 | list_for_each_entry_rcu(test, &file->triggers, list) { | |
1319 | test_enable_data = test->private_data; | |
1320 | if (test_enable_data && | |
1321 | (test_enable_data->file == enable_data->file)) { | |
1322 | ret = -EEXIST; | |
1323 | goto out; | |
1324 | } | |
1325 | } | |
1326 | ||
1327 | if (data->ops->init) { | |
1328 | ret = data->ops->init(data->ops, data); | |
1329 | if (ret < 0) | |
1330 | goto out; | |
1331 | } | |
1332 | ||
1333 | list_add_rcu(&data->list, &file->triggers); | |
1334 | ret++; | |
1335 | ||
4e4a4d75 | 1336 | update_cond_flag(file); |
7862ad18 TZ |
1337 | if (trace_event_trigger_enable_disable(file, 1) < 0) { |
1338 | list_del_rcu(&data->list); | |
4e4a4d75 | 1339 | update_cond_flag(file); |
7862ad18 TZ |
1340 | ret--; |
1341 | } | |
1342 | out: | |
1343 | return ret; | |
1344 | } | |
1345 | ||
1346 | static void event_enable_unregister_trigger(char *glob, | |
1347 | struct event_trigger_ops *ops, | |
1348 | struct event_trigger_data *test, | |
7f1d2f82 | 1349 | struct trace_event_file *file) |
7862ad18 TZ |
1350 | { |
1351 | struct enable_trigger_data *test_enable_data = test->private_data; | |
1352 | struct enable_trigger_data *enable_data; | |
1353 | struct event_trigger_data *data; | |
1354 | bool unregistered = false; | |
1355 | ||
1356 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
1357 | enable_data = data->private_data; | |
1358 | if (enable_data && | |
1359 | (enable_data->file == test_enable_data->file)) { | |
1360 | unregistered = true; | |
1361 | list_del_rcu(&data->list); | |
1362 | trace_event_trigger_enable_disable(file, 0); | |
4e4a4d75 | 1363 | update_cond_flag(file); |
7862ad18 TZ |
1364 | break; |
1365 | } | |
1366 | } | |
1367 | ||
1368 | if (unregistered && data->ops->free) | |
1369 | data->ops->free(data->ops, data); | |
1370 | } | |
1371 | ||
1372 | static struct event_trigger_ops * | |
1373 | event_enable_get_trigger_ops(char *cmd, char *param) | |
1374 | { | |
1375 | struct event_trigger_ops *ops; | |
1376 | bool enable; | |
1377 | ||
1378 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; | |
1379 | ||
1380 | if (enable) | |
1381 | ops = param ? &event_enable_count_trigger_ops : | |
1382 | &event_enable_trigger_ops; | |
1383 | else | |
1384 | ops = param ? &event_disable_count_trigger_ops : | |
1385 | &event_disable_trigger_ops; | |
1386 | ||
1387 | return ops; | |
1388 | } | |
1389 | ||
1390 | static struct event_command trigger_enable_cmd = { | |
1391 | .name = ENABLE_EVENT_STR, | |
1392 | .trigger_type = ETT_EVENT_ENABLE, | |
1393 | .func = event_enable_trigger_func, | |
1394 | .reg = event_enable_register_trigger, | |
1395 | .unreg = event_enable_unregister_trigger, | |
1396 | .get_trigger_ops = event_enable_get_trigger_ops, | |
bac5fb97 | 1397 | .set_filter = set_trigger_filter, |
7862ad18 TZ |
1398 | }; |
1399 | ||
1400 | static struct event_command trigger_disable_cmd = { | |
1401 | .name = DISABLE_EVENT_STR, | |
1402 | .trigger_type = ETT_EVENT_ENABLE, | |
1403 | .func = event_enable_trigger_func, | |
1404 | .reg = event_enable_register_trigger, | |
1405 | .unreg = event_enable_unregister_trigger, | |
1406 | .get_trigger_ops = event_enable_get_trigger_ops, | |
bac5fb97 | 1407 | .set_filter = set_trigger_filter, |
7862ad18 TZ |
1408 | }; |
1409 | ||
1410 | static __init void unregister_trigger_enable_disable_cmds(void) | |
1411 | { | |
1412 | unregister_event_command(&trigger_enable_cmd); | |
1413 | unregister_event_command(&trigger_disable_cmd); | |
1414 | } | |
1415 | ||
1416 | static __init int register_trigger_enable_disable_cmds(void) | |
1417 | { | |
1418 | int ret; | |
1419 | ||
1420 | ret = register_event_command(&trigger_enable_cmd); | |
1421 | if (WARN_ON(ret < 0)) | |
1422 | return ret; | |
1423 | ret = register_event_command(&trigger_disable_cmd); | |
1424 | if (WARN_ON(ret < 0)) | |
1425 | unregister_trigger_enable_disable_cmds(); | |
1426 | ||
1427 | return ret; | |
1428 | } | |
1429 | ||
2a2df321 TZ |
1430 | static __init int register_trigger_traceon_traceoff_cmds(void) |
1431 | { | |
1432 | int ret; | |
1433 | ||
1434 | ret = register_event_command(&trigger_traceon_cmd); | |
1435 | if (WARN_ON(ret < 0)) | |
1436 | return ret; | |
1437 | ret = register_event_command(&trigger_traceoff_cmd); | |
1438 | if (WARN_ON(ret < 0)) | |
1439 | unregister_trigger_traceon_traceoff_cmds(); | |
1440 | ||
1441 | return ret; | |
1442 | } | |
1443 | ||
85f2b082 TZ |
1444 | __init int register_trigger_cmds(void) |
1445 | { | |
2a2df321 | 1446 | register_trigger_traceon_traceoff_cmds(); |
93e31ffb | 1447 | register_trigger_snapshot_cmd(); |
f21ecbb3 | 1448 | register_trigger_stacktrace_cmd(); |
7862ad18 | 1449 | register_trigger_enable_disable_cmds(); |
2a2df321 | 1450 | |
85f2b082 TZ |
1451 | return 0; |
1452 | } |