1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * trace_events_trigger - trace event triggers |
4 | * |
5 | * Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com> |
6 | */ |
7 | |
8 | #include <linux/security.h> |
9 | #include <linux/module.h> |
10 | #include <linux/ctype.h> |
11 | #include <linux/mutex.h> |
12 | #include <linux/slab.h> |
13 | #include <linux/rculist.h> |
14 | |
15 | #include "trace.h" |
16 | |
17 | static LIST_HEAD(trigger_commands); |
18 | static DEFINE_MUTEX(trigger_cmd_mutex); |
19 | |
20 | void trigger_data_free(struct event_trigger_data *data) |
21 | { |
22 | if (data->cmd_ops->set_filter) |
23 | data->cmd_ops->set_filter(NULL, data, NULL); |
24 | |
25 | /* make sure current triggers exit before free */ |
26 | tracepoint_synchronize_unregister(); |
27 | |
28 | kfree(objp: data); |
29 | } |
30 | |
31 | /** |
32 | * event_triggers_call - Call triggers associated with a trace event |
33 | * @file: The trace_event_file associated with the event |
34 | * @buffer: The ring buffer that the event is being written to |
35 | * @rec: The trace entry for the event, NULL for unconditional invocation |
36 | * @event: The event meta data in the ring buffer |
37 | * |
38 | * For each trigger associated with an event, invoke the trigger |
39 | * function registered with the associated trigger command. If rec is |
40 | * non-NULL, it means that the trigger requires further processing and |
41 | * shouldn't be unconditionally invoked. If rec is non-NULL and the |
42 | * trigger has a filter associated with it, rec will checked against |
43 | * the filter and if the record matches the trigger will be invoked. |
44 | * If the trigger is a 'post_trigger', meaning it shouldn't be invoked |
45 | * in any case until the current event is written, the trigger |
46 | * function isn't invoked but the bit associated with the deferred |
47 | * trigger is set in the return value. |
48 | * |
49 | * Returns an enum event_trigger_type value containing a set bit for |
50 | * any trigger that should be deferred, ETT_NONE if nothing to defer. |
51 | * |
52 | * Called from tracepoint handlers (with rcu_read_lock_sched() held). |
53 | * |
54 | * Return: an enum event_trigger_type value containing a set bit for |
55 | * any trigger that should be deferred, ETT_NONE if nothing to defer. |
56 | */ |
57 | enum event_trigger_type |
58 | event_triggers_call(struct trace_event_file *file, |
59 | struct trace_buffer *buffer, void *rec, |
60 | struct ring_buffer_event *event) |
61 | { |
62 | struct event_trigger_data *data; |
63 | enum event_trigger_type tt = ETT_NONE; |
64 | struct event_filter *filter; |
65 | |
66 | if (list_empty(head: &file->triggers)) |
67 | return tt; |
68 | |
69 | list_for_each_entry_rcu(data, &file->triggers, list) { |
70 | if (data->paused) |
71 | continue; |
72 | if (!rec) { |
73 | data->ops->trigger(data, buffer, rec, event); |
74 | continue; |
75 | } |
76 | filter = rcu_dereference_sched(data->filter); |
77 | if (filter && !filter_match_preds(filter, rec)) |
78 | continue; |
79 | if (event_command_post_trigger(cmd_ops: data->cmd_ops)) { |
80 | tt |= data->cmd_ops->trigger_type; |
81 | continue; |
82 | } |
83 | data->ops->trigger(data, buffer, rec, event); |
84 | } |
85 | return tt; |
86 | } |
87 | EXPORT_SYMBOL_GPL(event_triggers_call); |
88 | |
89 | bool __trace_trigger_soft_disabled(struct trace_event_file *file) |
90 | { |
91 | unsigned long eflags = file->flags; |
92 | |
93 | if (eflags & EVENT_FILE_FL_TRIGGER_MODE) |
94 | event_triggers_call(file, NULL, NULL, NULL); |
95 | if (eflags & EVENT_FILE_FL_SOFT_DISABLED) |
96 | return true; |
97 | if (eflags & EVENT_FILE_FL_PID_FILTER) |
98 | return trace_event_ignore_this_pid(trace_file: file); |
99 | return false; |
100 | } |
101 | EXPORT_SYMBOL_GPL(__trace_trigger_soft_disabled); |
102 | |
103 | /** |
104 | * event_triggers_post_call - Call 'post_triggers' for a trace event |
105 | * @file: The trace_event_file associated with the event |
106 | * @tt: enum event_trigger_type containing a set bit for each trigger to invoke |
107 | * |
108 | * For each trigger associated with an event, invoke the trigger |
109 | * function registered with the associated trigger command, if the |
110 | * corresponding bit is set in the tt enum passed into this function. |
111 | * See @event_triggers_call for details on how those bits are set. |
112 | * |
113 | * Called from tracepoint handlers (with rcu_read_lock_sched() held). |
114 | */ |
115 | void |
116 | event_triggers_post_call(struct trace_event_file *file, |
117 | enum event_trigger_type tt) |
118 | { |
119 | struct event_trigger_data *data; |
120 | |
121 | list_for_each_entry_rcu(data, &file->triggers, list) { |
122 | if (data->paused) |
123 | continue; |
124 | if (data->cmd_ops->trigger_type & tt) |
125 | data->ops->trigger(data, NULL, NULL, NULL); |
126 | } |
127 | } |
128 | EXPORT_SYMBOL_GPL(event_triggers_post_call); |
129 | |
130 | #define SHOW_AVAILABLE_TRIGGERS (void *)(1UL) |
131 | |
132 | static void *trigger_next(struct seq_file *m, void *t, loff_t *pos) |
133 | { |
134 | struct trace_event_file *event_file = event_file_data(filp: m->private); |
135 | |
136 | if (t == SHOW_AVAILABLE_TRIGGERS) { |
137 | (*pos)++; |
138 | return NULL; |
139 | } |
140 | return seq_list_next(v: t, head: &event_file->triggers, ppos: pos); |
141 | } |
142 | |
143 | static bool check_user_trigger(struct trace_event_file *file) |
144 | { |
145 | struct event_trigger_data *data; |
146 | |
147 | list_for_each_entry_rcu(data, &file->triggers, list, |
148 | lockdep_is_held(&event_mutex)) { |
149 | if (data->flags & EVENT_TRIGGER_FL_PROBE) |
150 | continue; |
151 | return true; |
152 | } |
153 | return false; |
154 | } |
155 | |
156 | static void *trigger_start(struct seq_file *m, loff_t *pos) |
157 | { |
158 | struct trace_event_file *event_file; |
159 | |
160 | /* ->stop() is called even if ->start() fails */ |
161 | mutex_lock(&event_mutex); |
162 | event_file = event_file_data(filp: m->private); |
163 | if (unlikely(!event_file)) |
164 | return ERR_PTR(error: -ENODEV); |
165 | |
166 | if (list_empty(head: &event_file->triggers) || !check_user_trigger(file: event_file)) |
167 | return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL; |
168 | |
169 | return seq_list_start(head: &event_file->triggers, pos: *pos); |
170 | } |
171 | |
172 | static void trigger_stop(struct seq_file *m, void *t) |
173 | { |
174 | mutex_unlock(lock: &event_mutex); |
175 | } |
176 | |
177 | static int trigger_show(struct seq_file *m, void *v) |
178 | { |
179 | struct event_trigger_data *data; |
180 | struct event_command *p; |
181 | |
182 | if (v == SHOW_AVAILABLE_TRIGGERS) { |
183 | seq_puts(m, s: "# Available triggers:\n" ); |
184 | seq_putc(m, c: '#'); |
185 | mutex_lock(&trigger_cmd_mutex); |
186 | list_for_each_entry_reverse(p, &trigger_commands, list) |
187 | seq_printf(m, fmt: " %s" , p->name); |
188 | seq_putc(m, c: '\n'); |
189 | mutex_unlock(lock: &trigger_cmd_mutex); |
190 | return 0; |
191 | } |
192 | |
193 | data = list_entry(v, struct event_trigger_data, list); |
194 | data->ops->print(m, data); |
195 | |
196 | return 0; |
197 | } |
198 | |
199 | static const struct seq_operations event_triggers_seq_ops = { |
200 | .start = trigger_start, |
201 | .next = trigger_next, |
202 | .stop = trigger_stop, |
203 | .show = trigger_show, |
204 | }; |
205 | |
206 | static int event_trigger_regex_open(struct inode *inode, struct file *file) |
207 | { |
208 | int ret; |
209 | |
210 | ret = security_locked_down(what: LOCKDOWN_TRACEFS); |
211 | if (ret) |
212 | return ret; |
213 | |
214 | mutex_lock(&event_mutex); |
215 | |
216 | if (unlikely(!event_file_data(file))) { |
217 | mutex_unlock(lock: &event_mutex); |
218 | return -ENODEV; |
219 | } |
220 | |
221 | if ((file->f_mode & FMODE_WRITE) && |
222 | (file->f_flags & O_TRUNC)) { |
223 | struct trace_event_file *event_file; |
224 | struct event_command *p; |
225 | |
226 | event_file = event_file_data(filp: file); |
227 | |
228 | list_for_each_entry(p, &trigger_commands, list) { |
229 | if (p->unreg_all) |
230 | p->unreg_all(event_file); |
231 | } |
232 | } |
233 | |
234 | if (file->f_mode & FMODE_READ) { |
235 | ret = seq_open(file, &event_triggers_seq_ops); |
236 | if (!ret) { |
237 | struct seq_file *m = file->private_data; |
238 | m->private = file; |
239 | } |
240 | } |
241 | |
242 | mutex_unlock(lock: &event_mutex); |
243 | |
244 | return ret; |
245 | } |
246 | |
247 | int trigger_process_regex(struct trace_event_file *file, char *buff) |
248 | { |
249 | char *command, *next; |
250 | struct event_command *p; |
251 | int ret = -EINVAL; |
252 | |
253 | next = buff = skip_spaces(buff); |
254 | command = strsep(&next, ": \t" ); |
255 | if (next) { |
256 | next = skip_spaces(next); |
257 | if (!*next) |
258 | next = NULL; |
259 | } |
260 | command = (command[0] != '!') ? command : command + 1; |
261 | |
262 | mutex_lock(&trigger_cmd_mutex); |
263 | list_for_each_entry(p, &trigger_commands, list) { |
264 | if (strcmp(p->name, command) == 0) { |
265 | ret = p->parse(p, file, buff, command, next); |
266 | goto out_unlock; |
267 | } |
268 | } |
269 | out_unlock: |
270 | mutex_unlock(lock: &trigger_cmd_mutex); |
271 | |
272 | return ret; |
273 | } |
274 | |
275 | static ssize_t event_trigger_regex_write(struct file *file, |
276 | const char __user *ubuf, |
277 | size_t cnt, loff_t *ppos) |
278 | { |
279 | struct trace_event_file *event_file; |
280 | ssize_t ret; |
281 | char *buf; |
282 | |
283 | if (!cnt) |
284 | return 0; |
285 | |
286 | if (cnt >= PAGE_SIZE) |
287 | return -EINVAL; |
288 | |
289 | buf = memdup_user_nul(ubuf, cnt); |
290 | if (IS_ERR(ptr: buf)) |
291 | return PTR_ERR(ptr: buf); |
292 | |
293 | strim(buf); |
294 | |
295 | mutex_lock(&event_mutex); |
296 | event_file = event_file_data(filp: file); |
297 | if (unlikely(!event_file)) { |
298 | mutex_unlock(lock: &event_mutex); |
299 | kfree(objp: buf); |
300 | return -ENODEV; |
301 | } |
302 | ret = trigger_process_regex(file: event_file, buff: buf); |
303 | mutex_unlock(lock: &event_mutex); |
304 | |
305 | kfree(objp: buf); |
306 | if (ret < 0) |
307 | goto out; |
308 | |
309 | *ppos += cnt; |
310 | ret = cnt; |
311 | out: |
312 | return ret; |
313 | } |
314 | |
315 | static int event_trigger_regex_release(struct inode *inode, struct file *file) |
316 | { |
317 | mutex_lock(&event_mutex); |
318 | |
319 | if (file->f_mode & FMODE_READ) |
320 | seq_release(inode, file); |
321 | |
322 | mutex_unlock(lock: &event_mutex); |
323 | |
324 | return 0; |
325 | } |
326 | |
327 | static ssize_t |
328 | event_trigger_write(struct file *filp, const char __user *ubuf, |
329 | size_t cnt, loff_t *ppos) |
330 | { |
331 | return event_trigger_regex_write(file: filp, ubuf, cnt, ppos); |
332 | } |
333 | |
334 | static int |
335 | event_trigger_open(struct inode *inode, struct file *filp) |
336 | { |
337 | /* Checks for tracefs lockdown */ |
338 | return event_trigger_regex_open(inode, file: filp); |
339 | } |
340 | |
341 | static int |
342 | event_trigger_release(struct inode *inode, struct file *file) |
343 | { |
344 | return event_trigger_regex_release(inode, file); |
345 | } |
346 | |
347 | const struct file_operations event_trigger_fops = { |
348 | .open = event_trigger_open, |
349 | .read = seq_read, |
350 | .write = event_trigger_write, |
351 | .llseek = tracing_lseek, |
352 | .release = event_trigger_release, |
353 | }; |
354 | |
355 | /* |
356 | * Currently we only register event commands from __init, so mark this |
357 | * __init too. |
358 | */ |
359 | __init int register_event_command(struct event_command *cmd) |
360 | { |
361 | struct event_command *p; |
362 | int ret = 0; |
363 | |
364 | mutex_lock(&trigger_cmd_mutex); |
365 | list_for_each_entry(p, &trigger_commands, list) { |
366 | if (strcmp(cmd->name, p->name) == 0) { |
367 | ret = -EBUSY; |
368 | goto out_unlock; |
369 | } |
370 | } |
371 | list_add(new: &cmd->list, head: &trigger_commands); |
372 | out_unlock: |
373 | mutex_unlock(lock: &trigger_cmd_mutex); |
374 | |
375 | return ret; |
376 | } |
377 | |
378 | /* |
379 | * Currently we only unregister event commands from __init, so mark |
380 | * this __init too. |
381 | */ |
382 | __init int unregister_event_command(struct event_command *cmd) |
383 | { |
384 | struct event_command *p, *n; |
385 | int ret = -ENODEV; |
386 | |
387 | mutex_lock(&trigger_cmd_mutex); |
388 | list_for_each_entry_safe(p, n, &trigger_commands, list) { |
389 | if (strcmp(cmd->name, p->name) == 0) { |
390 | ret = 0; |
391 | list_del_init(entry: &p->list); |
392 | goto out_unlock; |
393 | } |
394 | } |
395 | out_unlock: |
396 | mutex_unlock(lock: &trigger_cmd_mutex); |
397 | |
398 | return ret; |
399 | } |
400 | |
401 | /** |
402 | * event_trigger_print - Generic event_trigger_ops @print implementation |
403 | * @name: The name of the event trigger |
404 | * @m: The seq_file being printed to |
405 | * @data: Trigger-specific data |
406 | * @filter_str: filter_str to print, if present |
407 | * |
408 | * Common implementation for event triggers to print themselves. |
409 | * |
410 | * Usually wrapped by a function that simply sets the @name of the |
411 | * trigger command and then invokes this. |
412 | * |
413 | * Return: 0 on success, errno otherwise |
414 | */ |
415 | static int |
416 | event_trigger_print(const char *name, struct seq_file *m, |
417 | void *data, char *filter_str) |
418 | { |
419 | long count = (long)data; |
420 | |
421 | seq_puts(m, s: name); |
422 | |
423 | if (count == -1) |
424 | seq_puts(m, s: ":unlimited" ); |
425 | else |
426 | seq_printf(m, fmt: ":count=%ld" , count); |
427 | |
428 | if (filter_str) |
429 | seq_printf(m, fmt: " if %s\n" , filter_str); |
430 | else |
431 | seq_putc(m, c: '\n'); |
432 | |
433 | return 0; |
434 | } |
435 | |
436 | /** |
437 | * event_trigger_init - Generic event_trigger_ops @init implementation |
438 | * @data: Trigger-specific data |
439 | * |
440 | * Common implementation of event trigger initialization. |
441 | * |
442 | * Usually used directly as the @init method in event trigger |
443 | * implementations. |
444 | * |
445 | * Return: 0 on success, errno otherwise |
446 | */ |
447 | int event_trigger_init(struct event_trigger_data *data) |
448 | { |
449 | data->ref++; |
450 | return 0; |
451 | } |
452 | |
453 | /** |
454 | * event_trigger_free - Generic event_trigger_ops @free implementation |
455 | * @data: Trigger-specific data |
456 | * |
457 | * Common implementation of event trigger de-initialization. |
458 | * |
459 | * Usually used directly as the @free method in event trigger |
460 | * implementations. |
461 | */ |
462 | static void |
463 | event_trigger_free(struct event_trigger_data *data) |
464 | { |
465 | if (WARN_ON_ONCE(data->ref <= 0)) |
466 | return; |
467 | |
468 | data->ref--; |
469 | if (!data->ref) |
470 | trigger_data_free(data); |
471 | } |
472 | |
473 | int trace_event_trigger_enable_disable(struct trace_event_file *file, |
474 | int trigger_enable) |
475 | { |
476 | int ret = 0; |
477 | |
478 | if (trigger_enable) { |
479 | if (atomic_inc_return(v: &file->tm_ref) > 1) |
480 | return ret; |
481 | set_bit(nr: EVENT_FILE_FL_TRIGGER_MODE_BIT, addr: &file->flags); |
482 | ret = trace_event_enable_disable(file, enable: 1, soft_disable: 1); |
483 | } else { |
484 | if (atomic_dec_return(v: &file->tm_ref) > 0) |
485 | return ret; |
486 | clear_bit(nr: EVENT_FILE_FL_TRIGGER_MODE_BIT, addr: &file->flags); |
487 | ret = trace_event_enable_disable(file, enable: 0, soft_disable: 1); |
488 | } |
489 | |
490 | return ret; |
491 | } |
492 | |
493 | /** |
494 | * clear_event_triggers - Clear all triggers associated with a trace array |
495 | * @tr: The trace array to clear |
496 | * |
497 | * For each trigger, the triggering event has its tm_ref decremented |
498 | * via trace_event_trigger_enable_disable(), and any associated event |
499 | * (in the case of enable/disable_event triggers) will have its sm_ref |
500 | * decremented via free()->trace_event_enable_disable(). That |
501 | * combination effectively reverses the soft-mode/trigger state added |
502 | * by trigger registration. |
503 | * |
504 | * Must be called with event_mutex held. |
505 | */ |
506 | void |
507 | clear_event_triggers(struct trace_array *tr) |
508 | { |
509 | struct trace_event_file *file; |
510 | |
511 | list_for_each_entry(file, &tr->events, list) { |
512 | struct event_trigger_data *data, *n; |
513 | list_for_each_entry_safe(data, n, &file->triggers, list) { |
514 | trace_event_trigger_enable_disable(file, trigger_enable: 0); |
515 | list_del_rcu(entry: &data->list); |
516 | if (data->ops->free) |
517 | data->ops->free(data); |
518 | } |
519 | } |
520 | } |
521 | |
522 | /** |
523 | * update_cond_flag - Set or reset the TRIGGER_COND bit |
524 | * @file: The trace_event_file associated with the event |
525 | * |
526 | * If an event has triggers and any of those triggers has a filter or |
527 | * a post_trigger, trigger invocation needs to be deferred until after |
528 | * the current event has logged its data, and the event should have |
529 | * its TRIGGER_COND bit set, otherwise the TRIGGER_COND bit should be |
530 | * cleared. |
531 | */ |
532 | void update_cond_flag(struct trace_event_file *file) |
533 | { |
534 | struct event_trigger_data *data; |
535 | bool set_cond = false; |
536 | |
537 | lockdep_assert_held(&event_mutex); |
538 | |
539 | list_for_each_entry(data, &file->triggers, list) { |
540 | if (data->filter || event_command_post_trigger(cmd_ops: data->cmd_ops) || |
541 | event_command_needs_rec(cmd_ops: data->cmd_ops)) { |
542 | set_cond = true; |
543 | break; |
544 | } |
545 | } |
546 | |
547 | if (set_cond) |
548 | set_bit(nr: EVENT_FILE_FL_TRIGGER_COND_BIT, addr: &file->flags); |
549 | else |
550 | clear_bit(nr: EVENT_FILE_FL_TRIGGER_COND_BIT, addr: &file->flags); |
551 | } |
552 | |
553 | /** |
554 | * register_trigger - Generic event_command @reg implementation |
555 | * @glob: The raw string used to register the trigger |
556 | * @data: Trigger-specific data to associate with the trigger |
557 | * @file: The trace_event_file associated with the event |
558 | * |
559 | * Common implementation for event trigger registration. |
560 | * |
561 | * Usually used directly as the @reg method in event command |
562 | * implementations. |
563 | * |
564 | * Return: 0 on success, errno otherwise |
565 | */ |
566 | static int register_trigger(char *glob, |
567 | struct event_trigger_data *data, |
568 | struct trace_event_file *file) |
569 | { |
570 | struct event_trigger_data *test; |
571 | int ret = 0; |
572 | |
573 | lockdep_assert_held(&event_mutex); |
574 | |
575 | list_for_each_entry(test, &file->triggers, list) { |
576 | if (test->cmd_ops->trigger_type == data->cmd_ops->trigger_type) { |
577 | ret = -EEXIST; |
578 | goto out; |
579 | } |
580 | } |
581 | |
582 | if (data->ops->init) { |
583 | ret = data->ops->init(data); |
584 | if (ret < 0) |
585 | goto out; |
586 | } |
587 | |
588 | list_add_rcu(new: &data->list, head: &file->triggers); |
589 | |
590 | update_cond_flag(file); |
591 | ret = trace_event_trigger_enable_disable(file, trigger_enable: 1); |
592 | if (ret < 0) { |
593 | list_del_rcu(entry: &data->list); |
594 | update_cond_flag(file); |
595 | } |
596 | out: |
597 | return ret; |
598 | } |
599 | |
600 | /* |
601 | * True if the trigger was found and unregistered, else false. |
602 | */ |
603 | static bool try_unregister_trigger(char *glob, |
604 | struct event_trigger_data *test, |
605 | struct trace_event_file *file) |
606 | { |
607 | struct event_trigger_data *data = NULL, *iter; |
608 | |
609 | lockdep_assert_held(&event_mutex); |
610 | |
611 | list_for_each_entry(iter, &file->triggers, list) { |
612 | if (iter->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { |
613 | data = iter; |
614 | list_del_rcu(entry: &data->list); |
615 | trace_event_trigger_enable_disable(file, trigger_enable: 0); |
616 | update_cond_flag(file); |
617 | break; |
618 | } |
619 | } |
620 | |
621 | if (data) { |
622 | if (data->ops->free) |
623 | data->ops->free(data); |
624 | |
625 | return true; |
626 | } |
627 | |
628 | return false; |
629 | } |
630 | |
631 | /** |
632 | * unregister_trigger - Generic event_command @unreg implementation |
633 | * @glob: The raw string used to register the trigger |
634 | * @test: Trigger-specific data used to find the trigger to remove |
635 | * @file: The trace_event_file associated with the event |
636 | * |
637 | * Common implementation for event trigger unregistration. |
638 | * |
639 | * Usually used directly as the @unreg method in event command |
640 | * implementations. |
641 | */ |
642 | static void unregister_trigger(char *glob, |
643 | struct event_trigger_data *test, |
644 | struct trace_event_file *file) |
645 | { |
646 | try_unregister_trigger(glob, test, file); |
647 | } |
648 | |
649 | /* |
650 | * Event trigger parsing helper functions. |
651 | * |
652 | * These functions help make it easier to write an event trigger |
653 | * parsing function i.e. the struct event_command.parse() callback |
654 | * function responsible for parsing and registering a trigger command |
655 | * written to the 'trigger' file. |
656 | * |
657 | * A trigger command (or just 'trigger' for short) takes the form: |
658 | * [trigger] [if filter] |
659 | * |
660 | * The struct event_command.parse() callback (and other struct |
661 | * event_command functions) refer to several components of a trigger |
662 | * command. Those same components are referenced by the event trigger |
663 | * parsing helper functions defined below. These components are: |
664 | * |
665 | * cmd - the trigger command name |
666 | * glob - the trigger command name optionally prefaced with '!' |
667 | * param_and_filter - text following cmd and ':' |
668 | * param - text following cmd and ':' and stripped of filter |
669 | * filter - the optional filter text following (and including) 'if' |
670 | * |
671 | * To illustrate the use of these componenents, here are some concrete |
672 | * examples. For the following triggers: |
673 | * |
674 | * echo 'traceon:5 if pid == 0' > trigger |
675 | * - 'traceon' is both cmd and glob |
676 | * - '5 if pid == 0' is the param_and_filter |
677 | * - '5' is the param |
678 | * - 'if pid == 0' is the filter |
679 | * |
680 | * echo 'enable_event:sys:event:n' > trigger |
681 | * - 'enable_event' is both cmd and glob |
682 | * - 'sys:event:n' is the param_and_filter |
683 | * - 'sys:event:n' is the param |
684 | * - there is no filter |
685 | * |
686 | * echo 'hist:keys=pid if prio > 50' > trigger |
687 | * - 'hist' is both cmd and glob |
688 | * - 'keys=pid if prio > 50' is the param_and_filter |
689 | * - 'keys=pid' is the param |
690 | * - 'if prio > 50' is the filter |
691 | * |
692 | * echo '!enable_event:sys:event:n' > trigger |
693 | * - 'enable_event' the cmd |
694 | * - '!enable_event' is the glob |
695 | * - 'sys:event:n' is the param_and_filter |
696 | * - 'sys:event:n' is the param |
697 | * - there is no filter |
698 | * |
699 | * echo 'traceoff' > trigger |
700 | * - 'traceoff' is both cmd and glob |
701 | * - there is no param_and_filter |
702 | * - there is no param |
703 | * - there is no filter |
704 | * |
705 | * There are a few different categories of event trigger covered by |
706 | * these helpers: |
707 | * |
708 | * - triggers that don't require a parameter e.g. traceon |
709 | * - triggers that do require a parameter e.g. enable_event and hist |
710 | * - triggers that though they may not require a param may support an |
711 | * optional 'n' param (n = number of times the trigger should fire) |
712 | * e.g.: traceon:5 or enable_event:sys:event:n |
713 | * - triggers that do not support an 'n' param e.g. hist |
714 | * |
715 | * These functions can be used or ignored as necessary - it all |
716 | * depends on the complexity of the trigger, and the granularity of |
717 | * the functions supported reflects the fact that some implementations |
718 | * may need to customize certain aspects of their implementations and |
719 | * won't need certain functions. For instance, the hist trigger |
720 | * implementation doesn't use event_trigger_separate_filter() because |
721 | * it has special requirements for handling the filter. |
722 | */ |
723 | |
724 | /** |
725 | * event_trigger_check_remove - check whether an event trigger specifies remove |
726 | * @glob: The trigger command string, with optional remove(!) operator |
727 | * |
728 | * The event trigger callback implementations pass in 'glob' as a |
729 | * parameter. This is the command name either with or without a |
730 | * remove(!) operator. This function simply parses the glob and |
731 | * determines whether the command corresponds to a trigger removal or |
732 | * a trigger addition. |
733 | * |
734 | * Return: true if this is a remove command, false otherwise |
735 | */ |
736 | bool event_trigger_check_remove(const char *glob) |
737 | { |
738 | return (glob && glob[0] == '!') ? true : false; |
739 | } |
740 | |
741 | /** |
742 | * event_trigger_empty_param - check whether the param is empty |
743 | * @param: The trigger param string |
744 | * |
745 | * The event trigger callback implementations pass in 'param' as a |
746 | * parameter. This corresponds to the string following the command |
747 | * name minus the command name. This function can be called by a |
748 | * callback implementation for any command that requires a param; a |
749 | * callback that doesn't require a param can ignore it. |
750 | * |
751 | * Return: true if this is an empty param, false otherwise |
752 | */ |
753 | bool event_trigger_empty_param(const char *param) |
754 | { |
755 | return !param; |
756 | } |
757 | |
758 | /** |
759 | * event_trigger_separate_filter - separate an event trigger from a filter |
760 | * @param_and_filter: String containing trigger and possibly filter |
761 | * @param: outparam, will be filled with a pointer to the trigger |
762 | * @filter: outparam, will be filled with a pointer to the filter |
763 | * @param_required: Specifies whether or not the param string is required |
764 | * |
765 | * Given a param string of the form '[trigger] [if filter]', this |
766 | * function separates the filter from the trigger and returns the |
767 | * trigger in @param and the filter in @filter. Either the @param |
768 | * or the @filter may be set to NULL by this function - if not set to |
769 | * NULL, they will contain strings corresponding to the trigger and |
770 | * filter. |
771 | * |
772 | * There are two cases that need to be handled with respect to the |
773 | * passed-in param: either the param is required, or it is not |
774 | * required. If @param_required is set, and there's no param, it will |
775 | * return -EINVAL. If @param_required is not set and there's a param |
776 | * that starts with a number, that corresponds to the case of a |
777 | * trigger with :n (n = number of times the trigger should fire) and |
778 | * the parsing continues normally; otherwise the function just returns |
779 | * and assumes param just contains a filter and there's nothing else |
780 | * to do. |
781 | * |
782 | * Return: 0 on success, errno otherwise |
783 | */ |
784 | int event_trigger_separate_filter(char *param_and_filter, char **param, |
785 | char **filter, bool param_required) |
786 | { |
787 | int ret = 0; |
788 | |
789 | *param = *filter = NULL; |
790 | |
791 | if (!param_and_filter) { |
792 | if (param_required) |
793 | ret = -EINVAL; |
794 | goto out; |
795 | } |
796 | |
797 | /* |
798 | * Here we check for an optional param. The only legal |
799 | * optional param is :n, and if that's the case, continue |
800 | * below. Otherwise we assume what's left is a filter and |
801 | * return it as the filter string for the caller to deal with. |
802 | */ |
803 | if (!param_required && param_and_filter && !isdigit(c: param_and_filter[0])) { |
804 | *filter = param_and_filter; |
805 | goto out; |
806 | } |
807 | |
808 | /* |
809 | * Separate the param from the filter (param [if filter]). |
810 | * Here we have either an optional :n param or a required |
811 | * param and an optional filter. |
812 | */ |
813 | *param = strsep(¶m_and_filter, " \t" ); |
814 | |
815 | /* |
816 | * Here we have a filter, though it may be empty. |
817 | */ |
818 | if (param_and_filter) { |
819 | *filter = skip_spaces(param_and_filter); |
820 | if (!**filter) |
821 | *filter = NULL; |
822 | } |
823 | out: |
824 | return ret; |
825 | } |
826 | |
827 | /** |
828 | * event_trigger_alloc - allocate and init event_trigger_data for a trigger |
829 | * @cmd_ops: The event_command operations for the trigger |
830 | * @cmd: The cmd string |
831 | * @param: The param string |
832 | * @private_data: User data to associate with the event trigger |
833 | * |
834 | * Allocate an event_trigger_data instance and initialize it. The |
835 | * @cmd_ops are used along with the @cmd and @param to get the |
836 | * trigger_ops to assign to the event_trigger_data. @private_data can |
837 | * also be passed in and associated with the event_trigger_data. |
838 | * |
839 | * Use event_trigger_free() to free an event_trigger_data object. |
840 | * |
841 | * Return: The trigger_data object success, NULL otherwise |
842 | */ |
843 | struct event_trigger_data *event_trigger_alloc(struct event_command *cmd_ops, |
844 | char *cmd, |
845 | char *param, |
846 | void *private_data) |
847 | { |
848 | struct event_trigger_data *trigger_data; |
849 | struct event_trigger_ops *trigger_ops; |
850 | |
851 | trigger_ops = cmd_ops->get_trigger_ops(cmd, param); |
852 | |
853 | trigger_data = kzalloc(size: sizeof(*trigger_data), GFP_KERNEL); |
854 | if (!trigger_data) |
855 | return NULL; |
856 | |
857 | trigger_data->count = -1; |
858 | trigger_data->ops = trigger_ops; |
859 | trigger_data->cmd_ops = cmd_ops; |
860 | trigger_data->private_data = private_data; |
861 | |
862 | INIT_LIST_HEAD(list: &trigger_data->list); |
863 | INIT_LIST_HEAD(list: &trigger_data->named_list); |
864 | RCU_INIT_POINTER(trigger_data->filter, NULL); |
865 | |
866 | return trigger_data; |
867 | } |
868 | |
869 | /** |
870 | * event_trigger_parse_num - parse and return the number param for a trigger |
871 | * @param: The param string |
872 | * @trigger_data: The trigger_data for the trigger |
873 | * |
874 | * Parse the :n (n = number of times the trigger should fire) param |
875 | * and set the count variable in the trigger_data to the parsed count. |
876 | * |
877 | * Return: 0 on success, errno otherwise |
878 | */ |
879 | int event_trigger_parse_num(char *param, |
880 | struct event_trigger_data *trigger_data) |
881 | { |
882 | char *number; |
883 | int ret = 0; |
884 | |
885 | if (param) { |
886 | number = strsep(¶m, ":" ); |
887 | |
888 | if (!strlen(number)) |
889 | return -EINVAL; |
890 | |
891 | /* |
892 | * We use the callback data field (which is a pointer) |
893 | * as our counter. |
894 | */ |
895 | ret = kstrtoul(s: number, base: 0, res: &trigger_data->count); |
896 | } |
897 | |
898 | return ret; |
899 | } |
900 | |
901 | /** |
902 | * event_trigger_set_filter - set an event trigger's filter |
903 | * @cmd_ops: The event_command operations for the trigger |
904 | * @file: The event file for the trigger's event |
905 | * @param: The string containing the filter |
906 | * @trigger_data: The trigger_data for the trigger |
907 | * |
908 | * Set the filter for the trigger. If the filter is NULL, just return |
909 | * without error. |
910 | * |
911 | * Return: 0 on success, errno otherwise |
912 | */ |
913 | int event_trigger_set_filter(struct event_command *cmd_ops, |
914 | struct trace_event_file *file, |
915 | char *param, |
916 | struct event_trigger_data *trigger_data) |
917 | { |
918 | if (param && cmd_ops->set_filter) |
919 | return cmd_ops->set_filter(param, trigger_data, file); |
920 | |
921 | return 0; |
922 | } |
923 | |
924 | /** |
925 | * event_trigger_reset_filter - reset an event trigger's filter |
926 | * @cmd_ops: The event_command operations for the trigger |
927 | * @trigger_data: The trigger_data for the trigger |
928 | * |
929 | * Reset the filter for the trigger to no filter. |
930 | */ |
931 | void event_trigger_reset_filter(struct event_command *cmd_ops, |
932 | struct event_trigger_data *trigger_data) |
933 | { |
934 | if (cmd_ops->set_filter) |
935 | cmd_ops->set_filter(NULL, trigger_data, NULL); |
936 | } |
937 | |
938 | /** |
939 | * event_trigger_register - register an event trigger |
940 | * @cmd_ops: The event_command operations for the trigger |
941 | * @file: The event file for the trigger's event |
942 | * @glob: The trigger command string, with optional remove(!) operator |
943 | * @trigger_data: The trigger_data for the trigger |
944 | * |
945 | * Register an event trigger. The @cmd_ops are used to call the |
946 | * cmd_ops->reg() function which actually does the registration. |
947 | * |
948 | * Return: 0 on success, errno otherwise |
949 | */ |
950 | int event_trigger_register(struct event_command *cmd_ops, |
951 | struct trace_event_file *file, |
952 | char *glob, |
953 | struct event_trigger_data *trigger_data) |
954 | { |
955 | return cmd_ops->reg(glob, trigger_data, file); |
956 | } |
957 | |
958 | /** |
959 | * event_trigger_unregister - unregister an event trigger |
960 | * @cmd_ops: The event_command operations for the trigger |
961 | * @file: The event file for the trigger's event |
962 | * @glob: The trigger command string, with optional remove(!) operator |
963 | * @trigger_data: The trigger_data for the trigger |
964 | * |
965 | * Unregister an event trigger. The @cmd_ops are used to call the |
966 | * cmd_ops->unreg() function which actually does the unregistration. |
967 | */ |
968 | void event_trigger_unregister(struct event_command *cmd_ops, |
969 | struct trace_event_file *file, |
970 | char *glob, |
971 | struct event_trigger_data *trigger_data) |
972 | { |
973 | cmd_ops->unreg(glob, trigger_data, file); |
974 | } |
975 | |
976 | /* |
977 | * End event trigger parsing helper functions. |
978 | */ |
979 | |
980 | /** |
981 | * event_trigger_parse - Generic event_command @parse implementation |
982 | * @cmd_ops: The command ops, used for trigger registration |
983 | * @file: The trace_event_file associated with the event |
984 | * @glob: The raw string used to register the trigger |
985 | * @cmd: The cmd portion of the string used to register the trigger |
986 | * @param_and_filter: The param and filter portion of the string used to register the trigger |
987 | * |
988 | * Common implementation for event command parsing and trigger |
989 | * instantiation. |
990 | * |
991 | * Usually used directly as the @parse method in event command |
992 | * implementations. |
993 | * |
994 | * Return: 0 on success, errno otherwise |
995 | */ |
996 | static int |
997 | event_trigger_parse(struct event_command *cmd_ops, |
998 | struct trace_event_file *file, |
999 | char *glob, char *cmd, char *param_and_filter) |
1000 | { |
1001 | struct event_trigger_data *trigger_data; |
1002 | char *param, *filter; |
1003 | bool remove; |
1004 | int ret; |
1005 | |
1006 | remove = event_trigger_check_remove(glob); |
1007 | |
1008 | ret = event_trigger_separate_filter(param_and_filter, param: ¶m, filter: &filter, param_required: false); |
1009 | if (ret) |
1010 | return ret; |
1011 | |
1012 | ret = -ENOMEM; |
1013 | trigger_data = event_trigger_alloc(cmd_ops, cmd, param, private_data: file); |
1014 | if (!trigger_data) |
1015 | goto out; |
1016 | |
1017 | if (remove) { |
1018 | event_trigger_unregister(cmd_ops, file, glob: glob+1, trigger_data); |
1019 | kfree(objp: trigger_data); |
1020 | ret = 0; |
1021 | goto out; |
1022 | } |
1023 | |
1024 | ret = event_trigger_parse_num(param, trigger_data); |
1025 | if (ret) |
1026 | goto out_free; |
1027 | |
1028 | ret = event_trigger_set_filter(cmd_ops, file, param: filter, trigger_data); |
1029 | if (ret < 0) |
1030 | goto out_free; |
1031 | |
1032 | /* Up the trigger_data count to make sure reg doesn't free it on failure */ |
1033 | event_trigger_init(data: trigger_data); |
1034 | |
1035 | ret = event_trigger_register(cmd_ops, file, glob, trigger_data); |
1036 | if (ret) |
1037 | goto out_free; |
1038 | |
1039 | /* Down the counter of trigger_data or free it if not used anymore */ |
1040 | event_trigger_free(data: trigger_data); |
1041 | out: |
1042 | return ret; |
1043 | |
1044 | out_free: |
1045 | event_trigger_reset_filter(cmd_ops, trigger_data); |
1046 | kfree(objp: trigger_data); |
1047 | goto out; |
1048 | } |
1049 | |
1050 | /** |
1051 | * set_trigger_filter - Generic event_command @set_filter implementation |
1052 | * @filter_str: The filter string for the trigger, NULL to remove filter |
1053 | * @trigger_data: Trigger-specific data |
1054 | * @file: The trace_event_file associated with the event |
1055 | * |
1056 | * Common implementation for event command filter parsing and filter |
1057 | * instantiation. |
1058 | * |
1059 | * Usually used directly as the @set_filter method in event command |
1060 | * implementations. |
1061 | * |
1062 | * Also used to remove a filter (if filter_str = NULL). |
1063 | * |
1064 | * Return: 0 on success, errno otherwise |
1065 | */ |
1066 | int set_trigger_filter(char *filter_str, |
1067 | struct event_trigger_data *trigger_data, |
1068 | struct trace_event_file *file) |
1069 | { |
1070 | struct event_trigger_data *data = trigger_data; |
1071 | struct event_filter *filter = NULL, *tmp; |
1072 | int ret = -EINVAL; |
1073 | char *s; |
1074 | |
1075 | if (!filter_str) /* clear the current filter */ |
1076 | goto assign; |
1077 | |
1078 | s = strsep(&filter_str, " \t" ); |
1079 | |
1080 | if (!strlen(s) || strcmp(s, "if" ) != 0) |
1081 | goto out; |
1082 | |
1083 | if (!filter_str) |
1084 | goto out; |
1085 | |
1086 | /* The filter is for the 'trigger' event, not the triggered event */ |
1087 | ret = create_event_filter(tr: file->tr, call: file->event_call, |
1088 | filter_str, set_str: true, filterp: &filter); |
1089 | |
1090 | /* Only enabled set_str for error handling */ |
1091 | if (filter) { |
1092 | kfree(objp: filter->filter_string); |
1093 | filter->filter_string = NULL; |
1094 | } |
1095 | |
1096 | /* |
1097 | * If create_event_filter() fails, filter still needs to be freed. |
1098 | * Which the calling code will do with data->filter. |
1099 | */ |
1100 | assign: |
1101 | tmp = rcu_access_pointer(data->filter); |
1102 | |
1103 | rcu_assign_pointer(data->filter, filter); |
1104 | |
1105 | if (tmp) { |
1106 | /* |
1107 | * Make sure the call is done with the filter. |
1108 | * It is possible that a filter could fail at boot up, |
1109 | * and then this path will be called. Avoid the synchronization |
1110 | * in that case. |
1111 | */ |
1112 | if (system_state != SYSTEM_BOOTING) |
1113 | tracepoint_synchronize_unregister(); |
1114 | free_event_filter(filter: tmp); |
1115 | } |
1116 | |
1117 | kfree(objp: data->filter_str); |
1118 | data->filter_str = NULL; |
1119 | |
1120 | if (filter_str) { |
1121 | data->filter_str = kstrdup(s: filter_str, GFP_KERNEL); |
1122 | if (!data->filter_str) { |
1123 | free_event_filter(rcu_access_pointer(data->filter)); |
1124 | data->filter = NULL; |
1125 | ret = -ENOMEM; |
1126 | } |
1127 | } |
1128 | out: |
1129 | return ret; |
1130 | } |
1131 | |
1132 | static LIST_HEAD(named_triggers); |
1133 | |
1134 | /** |
1135 | * find_named_trigger - Find the common named trigger associated with @name |
1136 | * @name: The name of the set of named triggers to find the common data for |
1137 | * |
1138 | * Named triggers are sets of triggers that share a common set of |
1139 | * trigger data. The first named trigger registered with a given name |
1140 | * owns the common trigger data that the others subsequently |
1141 | * registered with the same name will reference. This function |
1142 | * returns the common trigger data associated with that first |
1143 | * registered instance. |
1144 | * |
1145 | * Return: the common trigger data for the given named trigger on |
1146 | * success, NULL otherwise. |
1147 | */ |
1148 | struct event_trigger_data *find_named_trigger(const char *name) |
1149 | { |
1150 | struct event_trigger_data *data; |
1151 | |
1152 | if (!name) |
1153 | return NULL; |
1154 | |
1155 | list_for_each_entry(data, &named_triggers, named_list) { |
1156 | if (data->named_data) |
1157 | continue; |
1158 | if (strcmp(data->name, name) == 0) |
1159 | return data; |
1160 | } |
1161 | |
1162 | return NULL; |
1163 | } |
1164 | |
1165 | /** |
1166 | * is_named_trigger - determine if a given trigger is a named trigger |
1167 | * @test: The trigger data to test |
1168 | * |
1169 | * Return: true if 'test' is a named trigger, false otherwise. |
1170 | */ |
1171 | bool is_named_trigger(struct event_trigger_data *test) |
1172 | { |
1173 | struct event_trigger_data *data; |
1174 | |
1175 | list_for_each_entry(data, &named_triggers, named_list) { |
1176 | if (test == data) |
1177 | return true; |
1178 | } |
1179 | |
1180 | return false; |
1181 | } |
1182 | |
1183 | /** |
1184 | * save_named_trigger - save the trigger in the named trigger list |
1185 | * @name: The name of the named trigger set |
1186 | * @data: The trigger data to save |
1187 | * |
1188 | * Return: 0 if successful, negative error otherwise. |
1189 | */ |
1190 | int save_named_trigger(const char *name, struct event_trigger_data *data) |
1191 | { |
1192 | data->name = kstrdup(s: name, GFP_KERNEL); |
1193 | if (!data->name) |
1194 | return -ENOMEM; |
1195 | |
1196 | list_add(new: &data->named_list, head: &named_triggers); |
1197 | |
1198 | return 0; |
1199 | } |
1200 | |
1201 | /** |
1202 | * del_named_trigger - delete a trigger from the named trigger list |
1203 | * @data: The trigger data to delete |
1204 | */ |
1205 | void del_named_trigger(struct event_trigger_data *data) |
1206 | { |
1207 | kfree(objp: data->name); |
1208 | data->name = NULL; |
1209 | |
1210 | list_del(entry: &data->named_list); |
1211 | } |
1212 | |
1213 | static void __pause_named_trigger(struct event_trigger_data *data, bool pause) |
1214 | { |
1215 | struct event_trigger_data *test; |
1216 | |
1217 | list_for_each_entry(test, &named_triggers, named_list) { |
1218 | if (strcmp(test->name, data->name) == 0) { |
1219 | if (pause) { |
1220 | test->paused_tmp = test->paused; |
1221 | test->paused = true; |
1222 | } else { |
1223 | test->paused = test->paused_tmp; |
1224 | } |
1225 | } |
1226 | } |
1227 | } |
1228 | |
1229 | /** |
1230 | * pause_named_trigger - Pause all named triggers with the same name |
1231 | * @data: The trigger data of a named trigger to pause |
1232 | * |
1233 | * Pauses a named trigger along with all other triggers having the |
1234 | * same name. Because named triggers share a common set of data, |
1235 | * pausing only one is meaningless, so pausing one named trigger needs |
1236 | * to pause all triggers with the same name. |
1237 | */ |
1238 | void pause_named_trigger(struct event_trigger_data *data) |
1239 | { |
1240 | __pause_named_trigger(data, pause: true); |
1241 | } |
1242 | |
1243 | /** |
1244 | * unpause_named_trigger - Un-pause all named triggers with the same name |
1245 | * @data: The trigger data of a named trigger to unpause |
1246 | * |
1247 | * Un-pauses a named trigger along with all other triggers having the |
1248 | * same name. Because named triggers share a common set of data, |
1249 | * unpausing only one is meaningless, so unpausing one named trigger |
1250 | * needs to unpause all triggers with the same name. |
1251 | */ |
1252 | void unpause_named_trigger(struct event_trigger_data *data) |
1253 | { |
1254 | __pause_named_trigger(data, pause: false); |
1255 | } |
1256 | |
1257 | /** |
1258 | * set_named_trigger_data - Associate common named trigger data |
1259 | * @data: The trigger data to associate |
1260 | * @named_data: The common named trigger to be associated |
1261 | * |
1262 | * Named triggers are sets of triggers that share a common set of |
1263 | * trigger data. The first named trigger registered with a given name |
1264 | * owns the common trigger data that the others subsequently |
1265 | * registered with the same name will reference. This function |
1266 | * associates the common trigger data from the first trigger with the |
1267 | * given trigger. |
1268 | */ |
1269 | void set_named_trigger_data(struct event_trigger_data *data, |
1270 | struct event_trigger_data *named_data) |
1271 | { |
1272 | data->named_data = named_data; |
1273 | } |
1274 | |
1275 | struct event_trigger_data * |
1276 | get_named_trigger_data(struct event_trigger_data *data) |
1277 | { |
1278 | return data->named_data; |
1279 | } |
1280 | |
1281 | static void |
1282 | traceon_trigger(struct event_trigger_data *data, |
1283 | struct trace_buffer *buffer, void *rec, |
1284 | struct ring_buffer_event *event) |
1285 | { |
1286 | struct trace_event_file *file = data->private_data; |
1287 | |
1288 | if (file) { |
1289 | if (tracer_tracing_is_on(tr: file->tr)) |
1290 | return; |
1291 | |
1292 | tracer_tracing_on(tr: file->tr); |
1293 | return; |
1294 | } |
1295 | |
1296 | if (tracing_is_on()) |
1297 | return; |
1298 | |
1299 | tracing_on(); |
1300 | } |
1301 | |
1302 | static void |
1303 | traceon_count_trigger(struct event_trigger_data *data, |
1304 | struct trace_buffer *buffer, void *rec, |
1305 | struct ring_buffer_event *event) |
1306 | { |
1307 | struct trace_event_file *file = data->private_data; |
1308 | |
1309 | if (file) { |
1310 | if (tracer_tracing_is_on(tr: file->tr)) |
1311 | return; |
1312 | } else { |
1313 | if (tracing_is_on()) |
1314 | return; |
1315 | } |
1316 | |
1317 | if (!data->count) |
1318 | return; |
1319 | |
1320 | if (data->count != -1) |
1321 | (data->count)--; |
1322 | |
1323 | if (file) |
1324 | tracer_tracing_on(tr: file->tr); |
1325 | else |
1326 | tracing_on(); |
1327 | } |
1328 | |
1329 | static void |
1330 | traceoff_trigger(struct event_trigger_data *data, |
1331 | struct trace_buffer *buffer, void *rec, |
1332 | struct ring_buffer_event *event) |
1333 | { |
1334 | struct trace_event_file *file = data->private_data; |
1335 | |
1336 | if (file) { |
1337 | if (!tracer_tracing_is_on(tr: file->tr)) |
1338 | return; |
1339 | |
1340 | tracer_tracing_off(tr: file->tr); |
1341 | return; |
1342 | } |
1343 | |
1344 | if (!tracing_is_on()) |
1345 | return; |
1346 | |
1347 | tracing_off(); |
1348 | } |
1349 | |
1350 | static void |
1351 | traceoff_count_trigger(struct event_trigger_data *data, |
1352 | struct trace_buffer *buffer, void *rec, |
1353 | struct ring_buffer_event *event) |
1354 | { |
1355 | struct trace_event_file *file = data->private_data; |
1356 | |
1357 | if (file) { |
1358 | if (!tracer_tracing_is_on(tr: file->tr)) |
1359 | return; |
1360 | } else { |
1361 | if (!tracing_is_on()) |
1362 | return; |
1363 | } |
1364 | |
1365 | if (!data->count) |
1366 | return; |
1367 | |
1368 | if (data->count != -1) |
1369 | (data->count)--; |
1370 | |
1371 | if (file) |
1372 | tracer_tracing_off(tr: file->tr); |
1373 | else |
1374 | tracing_off(); |
1375 | } |
1376 | |
1377 | static int |
1378 | traceon_trigger_print(struct seq_file *m, struct event_trigger_data *data) |
1379 | { |
1380 | return event_trigger_print(name: "traceon" , m, data: (void *)data->count, |
1381 | filter_str: data->filter_str); |
1382 | } |
1383 | |
1384 | static int |
1385 | traceoff_trigger_print(struct seq_file *m, struct event_trigger_data *data) |
1386 | { |
1387 | return event_trigger_print(name: "traceoff" , m, data: (void *)data->count, |
1388 | filter_str: data->filter_str); |
1389 | } |
1390 | |
1391 | static struct event_trigger_ops traceon_trigger_ops = { |
1392 | .trigger = traceon_trigger, |
1393 | .print = traceon_trigger_print, |
1394 | .init = event_trigger_init, |
1395 | .free = event_trigger_free, |
1396 | }; |
1397 | |
1398 | static struct event_trigger_ops traceon_count_trigger_ops = { |
1399 | .trigger = traceon_count_trigger, |
1400 | .print = traceon_trigger_print, |
1401 | .init = event_trigger_init, |
1402 | .free = event_trigger_free, |
1403 | }; |
1404 | |
1405 | static struct event_trigger_ops traceoff_trigger_ops = { |
1406 | .trigger = traceoff_trigger, |
1407 | .print = traceoff_trigger_print, |
1408 | .init = event_trigger_init, |
1409 | .free = event_trigger_free, |
1410 | }; |
1411 | |
1412 | static struct event_trigger_ops traceoff_count_trigger_ops = { |
1413 | .trigger = traceoff_count_trigger, |
1414 | .print = traceoff_trigger_print, |
1415 | .init = event_trigger_init, |
1416 | .free = event_trigger_free, |
1417 | }; |
1418 | |
1419 | static struct event_trigger_ops * |
1420 | onoff_get_trigger_ops(char *cmd, char *param) |
1421 | { |
1422 | struct event_trigger_ops *ops; |
1423 | |
1424 | /* we register both traceon and traceoff to this callback */ |
1425 | if (strcmp(cmd, "traceon" ) == 0) |
1426 | ops = param ? &traceon_count_trigger_ops : |
1427 | &traceon_trigger_ops; |
1428 | else |
1429 | ops = param ? &traceoff_count_trigger_ops : |
1430 | &traceoff_trigger_ops; |
1431 | |
1432 | return ops; |
1433 | } |
1434 | |
1435 | static struct event_command trigger_traceon_cmd = { |
1436 | .name = "traceon" , |
1437 | .trigger_type = ETT_TRACE_ONOFF, |
1438 | .parse = event_trigger_parse, |
1439 | .reg = register_trigger, |
1440 | .unreg = unregister_trigger, |
1441 | .get_trigger_ops = onoff_get_trigger_ops, |
1442 | .set_filter = set_trigger_filter, |
1443 | }; |
1444 | |
1445 | static struct event_command trigger_traceoff_cmd = { |
1446 | .name = "traceoff" , |
1447 | .trigger_type = ETT_TRACE_ONOFF, |
1448 | .flags = EVENT_CMD_FL_POST_TRIGGER, |
1449 | .parse = event_trigger_parse, |
1450 | .reg = register_trigger, |
1451 | .unreg = unregister_trigger, |
1452 | .get_trigger_ops = onoff_get_trigger_ops, |
1453 | .set_filter = set_trigger_filter, |
1454 | }; |
1455 | |
1456 | #ifdef CONFIG_TRACER_SNAPSHOT |
1457 | static void |
1458 | snapshot_trigger(struct event_trigger_data *data, |
1459 | struct trace_buffer *buffer, void *rec, |
1460 | struct ring_buffer_event *event) |
1461 | { |
1462 | struct trace_event_file *file = data->private_data; |
1463 | |
1464 | if (file) |
1465 | tracing_snapshot_instance(tr: file->tr); |
1466 | else |
1467 | tracing_snapshot(); |
1468 | } |
1469 | |
1470 | static void |
1471 | snapshot_count_trigger(struct event_trigger_data *data, |
1472 | struct trace_buffer *buffer, void *rec, |
1473 | struct ring_buffer_event *event) |
1474 | { |
1475 | if (!data->count) |
1476 | return; |
1477 | |
1478 | if (data->count != -1) |
1479 | (data->count)--; |
1480 | |
1481 | snapshot_trigger(data, buffer, rec, event); |
1482 | } |
1483 | |
1484 | static int |
1485 | register_snapshot_trigger(char *glob, |
1486 | struct event_trigger_data *data, |
1487 | struct trace_event_file *file) |
1488 | { |
1489 | int ret = tracing_arm_snapshot(tr: file->tr); |
1490 | |
1491 | if (ret < 0) |
1492 | return ret; |
1493 | |
1494 | ret = register_trigger(glob, data, file); |
1495 | if (ret < 0) |
1496 | tracing_disarm_snapshot(tr: file->tr); |
1497 | return ret; |
1498 | } |
1499 | |
1500 | static void unregister_snapshot_trigger(char *glob, |
1501 | struct event_trigger_data *data, |
1502 | struct trace_event_file *file) |
1503 | { |
1504 | if (try_unregister_trigger(glob, test: data, file)) |
1505 | tracing_disarm_snapshot(tr: file->tr); |
1506 | } |
1507 | |
1508 | static int |
1509 | snapshot_trigger_print(struct seq_file *m, struct event_trigger_data *data) |
1510 | { |
1511 | return event_trigger_print(name: "snapshot" , m, data: (void *)data->count, |
1512 | filter_str: data->filter_str); |
1513 | } |
1514 | |
1515 | static struct event_trigger_ops snapshot_trigger_ops = { |
1516 | .trigger = snapshot_trigger, |
1517 | .print = snapshot_trigger_print, |
1518 | .init = event_trigger_init, |
1519 | .free = event_trigger_free, |
1520 | }; |
1521 | |
1522 | static struct event_trigger_ops snapshot_count_trigger_ops = { |
1523 | .trigger = snapshot_count_trigger, |
1524 | .print = snapshot_trigger_print, |
1525 | .init = event_trigger_init, |
1526 | .free = event_trigger_free, |
1527 | }; |
1528 | |
1529 | static struct event_trigger_ops * |
1530 | snapshot_get_trigger_ops(char *cmd, char *param) |
1531 | { |
1532 | return param ? &snapshot_count_trigger_ops : &snapshot_trigger_ops; |
1533 | } |
1534 | |
1535 | static struct event_command trigger_snapshot_cmd = { |
1536 | .name = "snapshot" , |
1537 | .trigger_type = ETT_SNAPSHOT, |
1538 | .parse = event_trigger_parse, |
1539 | .reg = register_snapshot_trigger, |
1540 | .unreg = unregister_snapshot_trigger, |
1541 | .get_trigger_ops = snapshot_get_trigger_ops, |
1542 | .set_filter = set_trigger_filter, |
1543 | }; |
1544 | |
1545 | static __init int register_trigger_snapshot_cmd(void) |
1546 | { |
1547 | int ret; |
1548 | |
1549 | ret = register_event_command(cmd: &trigger_snapshot_cmd); |
1550 | WARN_ON(ret < 0); |
1551 | |
1552 | return ret; |
1553 | } |
1554 | #else |
1555 | static __init int register_trigger_snapshot_cmd(void) { return 0; } |
1556 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
1557 | |
1558 | #ifdef CONFIG_STACKTRACE |
1559 | #ifdef CONFIG_UNWINDER_ORC |
1560 | /* Skip 2: |
1561 | * event_triggers_post_call() |
1562 | * trace_event_raw_event_xxx() |
1563 | */ |
1564 | # define STACK_SKIP 2 |
1565 | #else |
1566 | /* |
1567 | * Skip 4: |
1568 | * stacktrace_trigger() |
1569 | * event_triggers_post_call() |
1570 | * trace_event_buffer_commit() |
1571 | * trace_event_raw_event_xxx() |
1572 | */ |
1573 | #define STACK_SKIP 4 |
1574 | #endif |
1575 | |
1576 | static void |
1577 | stacktrace_trigger(struct event_trigger_data *data, |
1578 | struct trace_buffer *buffer, void *rec, |
1579 | struct ring_buffer_event *event) |
1580 | { |
1581 | struct trace_event_file *file = data->private_data; |
1582 | |
1583 | if (file) |
1584 | __trace_stack(tr: file->tr, trace_ctx: tracing_gen_ctx(), STACK_SKIP); |
1585 | else |
1586 | trace_dump_stack(STACK_SKIP); |
1587 | } |
1588 | |
1589 | static void |
1590 | stacktrace_count_trigger(struct event_trigger_data *data, |
1591 | struct trace_buffer *buffer, void *rec, |
1592 | struct ring_buffer_event *event) |
1593 | { |
1594 | if (!data->count) |
1595 | return; |
1596 | |
1597 | if (data->count != -1) |
1598 | (data->count)--; |
1599 | |
1600 | stacktrace_trigger(data, buffer, rec, event); |
1601 | } |
1602 | |
1603 | static int |
1604 | stacktrace_trigger_print(struct seq_file *m, struct event_trigger_data *data) |
1605 | { |
1606 | return event_trigger_print(name: "stacktrace" , m, data: (void *)data->count, |
1607 | filter_str: data->filter_str); |
1608 | } |
1609 | |
1610 | static struct event_trigger_ops stacktrace_trigger_ops = { |
1611 | .trigger = stacktrace_trigger, |
1612 | .print = stacktrace_trigger_print, |
1613 | .init = event_trigger_init, |
1614 | .free = event_trigger_free, |
1615 | }; |
1616 | |
1617 | static struct event_trigger_ops stacktrace_count_trigger_ops = { |
1618 | .trigger = stacktrace_count_trigger, |
1619 | .print = stacktrace_trigger_print, |
1620 | .init = event_trigger_init, |
1621 | .free = event_trigger_free, |
1622 | }; |
1623 | |
1624 | static struct event_trigger_ops * |
1625 | stacktrace_get_trigger_ops(char *cmd, char *param) |
1626 | { |
1627 | return param ? &stacktrace_count_trigger_ops : &stacktrace_trigger_ops; |
1628 | } |
1629 | |
1630 | static struct event_command trigger_stacktrace_cmd = { |
1631 | .name = "stacktrace" , |
1632 | .trigger_type = ETT_STACKTRACE, |
1633 | .flags = EVENT_CMD_FL_POST_TRIGGER, |
1634 | .parse = event_trigger_parse, |
1635 | .reg = register_trigger, |
1636 | .unreg = unregister_trigger, |
1637 | .get_trigger_ops = stacktrace_get_trigger_ops, |
1638 | .set_filter = set_trigger_filter, |
1639 | }; |
1640 | |
1641 | static __init int register_trigger_stacktrace_cmd(void) |
1642 | { |
1643 | int ret; |
1644 | |
1645 | ret = register_event_command(cmd: &trigger_stacktrace_cmd); |
1646 | WARN_ON(ret < 0); |
1647 | |
1648 | return ret; |
1649 | } |
1650 | #else |
1651 | static __init int register_trigger_stacktrace_cmd(void) { return 0; } |
1652 | #endif /* CONFIG_STACKTRACE */ |
1653 | |
1654 | static __init void unregister_trigger_traceon_traceoff_cmds(void) |
1655 | { |
1656 | unregister_event_command(cmd: &trigger_traceon_cmd); |
1657 | unregister_event_command(cmd: &trigger_traceoff_cmd); |
1658 | } |
1659 | |
1660 | static void |
1661 | event_enable_trigger(struct event_trigger_data *data, |
1662 | struct trace_buffer *buffer, void *rec, |
1663 | struct ring_buffer_event *event) |
1664 | { |
1665 | struct enable_trigger_data *enable_data = data->private_data; |
1666 | |
1667 | if (enable_data->enable) |
1668 | clear_bit(nr: EVENT_FILE_FL_SOFT_DISABLED_BIT, addr: &enable_data->file->flags); |
1669 | else |
1670 | set_bit(nr: EVENT_FILE_FL_SOFT_DISABLED_BIT, addr: &enable_data->file->flags); |
1671 | } |
1672 | |
1673 | static void |
1674 | event_enable_count_trigger(struct event_trigger_data *data, |
1675 | struct trace_buffer *buffer, void *rec, |
1676 | struct ring_buffer_event *event) |
1677 | { |
1678 | struct enable_trigger_data *enable_data = data->private_data; |
1679 | |
1680 | if (!data->count) |
1681 | return; |
1682 | |
1683 | /* Skip if the event is in a state we want to switch to */ |
1684 | if (enable_data->enable == !(enable_data->file->flags & EVENT_FILE_FL_SOFT_DISABLED)) |
1685 | return; |
1686 | |
1687 | if (data->count != -1) |
1688 | (data->count)--; |
1689 | |
1690 | event_enable_trigger(data, buffer, rec, event); |
1691 | } |
1692 | |
1693 | int event_enable_trigger_print(struct seq_file *m, |
1694 | struct event_trigger_data *data) |
1695 | { |
1696 | struct enable_trigger_data *enable_data = data->private_data; |
1697 | |
1698 | seq_printf(m, fmt: "%s:%s:%s" , |
1699 | enable_data->hist ? |
1700 | (enable_data->enable ? ENABLE_HIST_STR : DISABLE_HIST_STR) : |
1701 | (enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR), |
1702 | enable_data->file->event_call->class->system, |
1703 | trace_event_name(call: enable_data->file->event_call)); |
1704 | |
1705 | if (data->count == -1) |
1706 | seq_puts(m, s: ":unlimited" ); |
1707 | else |
1708 | seq_printf(m, fmt: ":count=%ld" , data->count); |
1709 | |
1710 | if (data->filter_str) |
1711 | seq_printf(m, fmt: " if %s\n" , data->filter_str); |
1712 | else |
1713 | seq_putc(m, c: '\n'); |
1714 | |
1715 | return 0; |
1716 | } |
1717 | |
1718 | void event_enable_trigger_free(struct event_trigger_data *data) |
1719 | { |
1720 | struct enable_trigger_data *enable_data = data->private_data; |
1721 | |
1722 | if (WARN_ON_ONCE(data->ref <= 0)) |
1723 | return; |
1724 | |
1725 | data->ref--; |
1726 | if (!data->ref) { |
1727 | /* Remove the SOFT_MODE flag */ |
1728 | trace_event_enable_disable(file: enable_data->file, enable: 0, soft_disable: 1); |
1729 | trace_event_put_ref(call: enable_data->file->event_call); |
1730 | trigger_data_free(data); |
1731 | kfree(objp: enable_data); |
1732 | } |
1733 | } |
1734 | |
1735 | static struct event_trigger_ops event_enable_trigger_ops = { |
1736 | .trigger = event_enable_trigger, |
1737 | .print = event_enable_trigger_print, |
1738 | .init = event_trigger_init, |
1739 | .free = event_enable_trigger_free, |
1740 | }; |
1741 | |
1742 | static struct event_trigger_ops event_enable_count_trigger_ops = { |
1743 | .trigger = event_enable_count_trigger, |
1744 | .print = event_enable_trigger_print, |
1745 | .init = event_trigger_init, |
1746 | .free = event_enable_trigger_free, |
1747 | }; |
1748 | |
1749 | static struct event_trigger_ops event_disable_trigger_ops = { |
1750 | .trigger = event_enable_trigger, |
1751 | .print = event_enable_trigger_print, |
1752 | .init = event_trigger_init, |
1753 | .free = event_enable_trigger_free, |
1754 | }; |
1755 | |
1756 | static struct event_trigger_ops event_disable_count_trigger_ops = { |
1757 | .trigger = event_enable_count_trigger, |
1758 | .print = event_enable_trigger_print, |
1759 | .init = event_trigger_init, |
1760 | .free = event_enable_trigger_free, |
1761 | }; |
1762 | |
1763 | int event_enable_trigger_parse(struct event_command *cmd_ops, |
1764 | struct trace_event_file *file, |
1765 | char *glob, char *cmd, char *param_and_filter) |
1766 | { |
1767 | struct trace_event_file *event_enable_file; |
1768 | struct enable_trigger_data *enable_data; |
1769 | struct event_trigger_data *trigger_data; |
1770 | struct trace_array *tr = file->tr; |
1771 | char *param, *filter; |
1772 | bool enable, remove; |
1773 | const char *system; |
1774 | const char *event; |
1775 | bool hist = false; |
1776 | int ret; |
1777 | |
1778 | remove = event_trigger_check_remove(glob); |
1779 | |
1780 | if (event_trigger_empty_param(param: param_and_filter)) |
1781 | return -EINVAL; |
1782 | |
1783 | ret = event_trigger_separate_filter(param_and_filter, param: ¶m, filter: &filter, param_required: true); |
1784 | if (ret) |
1785 | return ret; |
1786 | |
1787 | system = strsep(¶m, ":" ); |
1788 | if (!param) |
1789 | return -EINVAL; |
1790 | |
1791 | event = strsep(¶m, ":" ); |
1792 | |
1793 | ret = -EINVAL; |
1794 | event_enable_file = find_event_file(tr, system, event); |
1795 | if (!event_enable_file) |
1796 | goto out; |
1797 | |
1798 | #ifdef CONFIG_HIST_TRIGGERS |
1799 | hist = ((strcmp(cmd, ENABLE_HIST_STR) == 0) || |
1800 | (strcmp(cmd, DISABLE_HIST_STR) == 0)); |
1801 | |
1802 | enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || |
1803 | (strcmp(cmd, ENABLE_HIST_STR) == 0)); |
1804 | #else |
1805 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; |
1806 | #endif |
1807 | ret = -ENOMEM; |
1808 | |
1809 | enable_data = kzalloc(size: sizeof(*enable_data), GFP_KERNEL); |
1810 | if (!enable_data) |
1811 | goto out; |
1812 | |
1813 | enable_data->hist = hist; |
1814 | enable_data->enable = enable; |
1815 | enable_data->file = event_enable_file; |
1816 | |
1817 | trigger_data = event_trigger_alloc(cmd_ops, cmd, param, private_data: enable_data); |
1818 | if (!trigger_data) { |
1819 | kfree(objp: enable_data); |
1820 | goto out; |
1821 | } |
1822 | |
1823 | if (remove) { |
1824 | event_trigger_unregister(cmd_ops, file, glob: glob+1, trigger_data); |
1825 | kfree(objp: trigger_data); |
1826 | kfree(objp: enable_data); |
1827 | ret = 0; |
1828 | goto out; |
1829 | } |
1830 | |
1831 | /* Up the trigger_data count to make sure nothing frees it on failure */ |
1832 | event_trigger_init(data: trigger_data); |
1833 | |
1834 | ret = event_trigger_parse_num(param, trigger_data); |
1835 | if (ret) |
1836 | goto out_free; |
1837 | |
1838 | ret = event_trigger_set_filter(cmd_ops, file, param: filter, trigger_data); |
1839 | if (ret < 0) |
1840 | goto out_free; |
1841 | |
1842 | /* Don't let event modules unload while probe registered */ |
1843 | ret = trace_event_try_get_ref(call: event_enable_file->event_call); |
1844 | if (!ret) { |
1845 | ret = -EBUSY; |
1846 | goto out_free; |
1847 | } |
1848 | |
1849 | ret = trace_event_enable_disable(file: event_enable_file, enable: 1, soft_disable: 1); |
1850 | if (ret < 0) |
1851 | goto out_put; |
1852 | |
1853 | ret = event_trigger_register(cmd_ops, file, glob, trigger_data); |
1854 | if (ret) |
1855 | goto out_disable; |
1856 | |
1857 | event_trigger_free(data: trigger_data); |
1858 | out: |
1859 | return ret; |
1860 | out_disable: |
1861 | trace_event_enable_disable(file: event_enable_file, enable: 0, soft_disable: 1); |
1862 | out_put: |
1863 | trace_event_put_ref(call: event_enable_file->event_call); |
1864 | out_free: |
1865 | event_trigger_reset_filter(cmd_ops, trigger_data); |
1866 | event_trigger_free(data: trigger_data); |
1867 | kfree(objp: enable_data); |
1868 | |
1869 | goto out; |
1870 | } |
1871 | |
1872 | int event_enable_register_trigger(char *glob, |
1873 | struct event_trigger_data *data, |
1874 | struct trace_event_file *file) |
1875 | { |
1876 | struct enable_trigger_data *enable_data = data->private_data; |
1877 | struct enable_trigger_data *test_enable_data; |
1878 | struct event_trigger_data *test; |
1879 | int ret = 0; |
1880 | |
1881 | lockdep_assert_held(&event_mutex); |
1882 | |
1883 | list_for_each_entry(test, &file->triggers, list) { |
1884 | test_enable_data = test->private_data; |
1885 | if (test_enable_data && |
1886 | (test->cmd_ops->trigger_type == |
1887 | data->cmd_ops->trigger_type) && |
1888 | (test_enable_data->file == enable_data->file)) { |
1889 | ret = -EEXIST; |
1890 | goto out; |
1891 | } |
1892 | } |
1893 | |
1894 | if (data->ops->init) { |
1895 | ret = data->ops->init(data); |
1896 | if (ret < 0) |
1897 | goto out; |
1898 | } |
1899 | |
1900 | list_add_rcu(new: &data->list, head: &file->triggers); |
1901 | |
1902 | update_cond_flag(file); |
1903 | ret = trace_event_trigger_enable_disable(file, trigger_enable: 1); |
1904 | if (ret < 0) { |
1905 | list_del_rcu(entry: &data->list); |
1906 | update_cond_flag(file); |
1907 | } |
1908 | out: |
1909 | return ret; |
1910 | } |
1911 | |
1912 | void event_enable_unregister_trigger(char *glob, |
1913 | struct event_trigger_data *test, |
1914 | struct trace_event_file *file) |
1915 | { |
1916 | struct enable_trigger_data *test_enable_data = test->private_data; |
1917 | struct event_trigger_data *data = NULL, *iter; |
1918 | struct enable_trigger_data *enable_data; |
1919 | |
1920 | lockdep_assert_held(&event_mutex); |
1921 | |
1922 | list_for_each_entry(iter, &file->triggers, list) { |
1923 | enable_data = iter->private_data; |
1924 | if (enable_data && |
1925 | (iter->cmd_ops->trigger_type == |
1926 | test->cmd_ops->trigger_type) && |
1927 | (enable_data->file == test_enable_data->file)) { |
1928 | data = iter; |
1929 | list_del_rcu(entry: &data->list); |
1930 | trace_event_trigger_enable_disable(file, trigger_enable: 0); |
1931 | update_cond_flag(file); |
1932 | break; |
1933 | } |
1934 | } |
1935 | |
1936 | if (data && data->ops->free) |
1937 | data->ops->free(data); |
1938 | } |
1939 | |
1940 | static struct event_trigger_ops * |
1941 | event_enable_get_trigger_ops(char *cmd, char *param) |
1942 | { |
1943 | struct event_trigger_ops *ops; |
1944 | bool enable; |
1945 | |
1946 | #ifdef CONFIG_HIST_TRIGGERS |
1947 | enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || |
1948 | (strcmp(cmd, ENABLE_HIST_STR) == 0)); |
1949 | #else |
1950 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; |
1951 | #endif |
1952 | if (enable) |
1953 | ops = param ? &event_enable_count_trigger_ops : |
1954 | &event_enable_trigger_ops; |
1955 | else |
1956 | ops = param ? &event_disable_count_trigger_ops : |
1957 | &event_disable_trigger_ops; |
1958 | |
1959 | return ops; |
1960 | } |
1961 | |
1962 | static struct event_command trigger_enable_cmd = { |
1963 | .name = ENABLE_EVENT_STR, |
1964 | .trigger_type = ETT_EVENT_ENABLE, |
1965 | .parse = event_enable_trigger_parse, |
1966 | .reg = event_enable_register_trigger, |
1967 | .unreg = event_enable_unregister_trigger, |
1968 | .get_trigger_ops = event_enable_get_trigger_ops, |
1969 | .set_filter = set_trigger_filter, |
1970 | }; |
1971 | |
1972 | static struct event_command trigger_disable_cmd = { |
1973 | .name = DISABLE_EVENT_STR, |
1974 | .trigger_type = ETT_EVENT_ENABLE, |
1975 | .parse = event_enable_trigger_parse, |
1976 | .reg = event_enable_register_trigger, |
1977 | .unreg = event_enable_unregister_trigger, |
1978 | .get_trigger_ops = event_enable_get_trigger_ops, |
1979 | .set_filter = set_trigger_filter, |
1980 | }; |
1981 | |
1982 | static __init void unregister_trigger_enable_disable_cmds(void) |
1983 | { |
1984 | unregister_event_command(cmd: &trigger_enable_cmd); |
1985 | unregister_event_command(cmd: &trigger_disable_cmd); |
1986 | } |
1987 | |
1988 | static __init int register_trigger_enable_disable_cmds(void) |
1989 | { |
1990 | int ret; |
1991 | |
1992 | ret = register_event_command(cmd: &trigger_enable_cmd); |
1993 | if (WARN_ON(ret < 0)) |
1994 | return ret; |
1995 | ret = register_event_command(cmd: &trigger_disable_cmd); |
1996 | if (WARN_ON(ret < 0)) |
1997 | unregister_trigger_enable_disable_cmds(); |
1998 | |
1999 | return ret; |
2000 | } |
2001 | |
2002 | static __init int register_trigger_traceon_traceoff_cmds(void) |
2003 | { |
2004 | int ret; |
2005 | |
2006 | ret = register_event_command(cmd: &trigger_traceon_cmd); |
2007 | if (WARN_ON(ret < 0)) |
2008 | return ret; |
2009 | ret = register_event_command(cmd: &trigger_traceoff_cmd); |
2010 | if (WARN_ON(ret < 0)) |
2011 | unregister_trigger_traceon_traceoff_cmds(); |
2012 | |
2013 | return ret; |
2014 | } |
2015 | |
2016 | __init int register_trigger_cmds(void) |
2017 | { |
2018 | register_trigger_traceon_traceoff_cmds(); |
2019 | register_trigger_snapshot_cmd(); |
2020 | register_trigger_stacktrace_cmd(); |
2021 | register_trigger_enable_disable_cmds(); |
2022 | register_trigger_hist_enable_disable_cmds(); |
2023 | register_trigger_hist_cmd(); |
2024 | |
2025 | return 0; |
2026 | } |
2027 | |