Commit | Line | Data |
---|---|---|
bcea3f96 | 1 | // SPDX-License-Identifier: GPL-2.0 |
85f2b082 TZ |
2 | /* |
3 | * trace_events_trigger - trace event triggers | |
4 | * | |
85f2b082 TZ |
5 | * Copyright (C) 2013 Tom Zanussi <tom.zanussi@linux.intel.com> |
6 | */ | |
7 | ||
17911ff3 | 8 | #include <linux/security.h> |
85f2b082 TZ |
9 | #include <linux/module.h> |
10 | #include <linux/ctype.h> | |
11 | #include <linux/mutex.h> | |
12 | #include <linux/slab.h> | |
b2d09103 | 13 | #include <linux/rculist.h> |
85f2b082 TZ |
14 | |
15 | #include "trace.h" | |
16 | ||
17 | static LIST_HEAD(trigger_commands); | |
18 | static DEFINE_MUTEX(trigger_cmd_mutex); | |
19 | ||
ab4bf008 | 20 | void trigger_data_free(struct event_trigger_data *data) |
2a2df321 | 21 | { |
bac5fb97 TZ |
22 | if (data->cmd_ops->set_filter) |
23 | data->cmd_ops->set_filter(NULL, data, NULL); | |
24 | ||
e0a568dc SRV |
25 | /* make sure current triggers exit before free */ |
26 | tracepoint_synchronize_unregister(); | |
27 | ||
2a2df321 TZ |
28 | kfree(data); |
29 | } | |
30 | ||
85f2b082 TZ |
31 | /** |
32 | * event_triggers_call - Call triggers associated with a trace event | |
7f1d2f82 | 33 | * @file: The trace_event_file associated with the event |
bd7217f3 | 34 | * @buffer: The ring buffer that the event is being written to |
bac5fb97 | 35 | * @rec: The trace entry for the event, NULL for unconditional invocation |
bd7217f3 | 36 | * @event: The event meta data in the ring buffer |
85f2b082 TZ |
37 | * |
38 | * For each trigger associated with an event, invoke the trigger | |
bac5fb97 TZ |
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. | |
85f2b082 TZ |
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 | */ | |
bac5fb97 | 57 | enum event_trigger_type |
b47e3302 SRV |
58 | event_triggers_call(struct trace_event_file *file, |
59 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 60 | struct ring_buffer_event *event) |
85f2b082 TZ |
61 | { |
62 | struct event_trigger_data *data; | |
bac5fb97 | 63 | enum event_trigger_type tt = ETT_NONE; |
d8a30f20 | 64 | struct event_filter *filter; |
85f2b082 TZ |
65 | |
66 | if (list_empty(&file->triggers)) | |
bac5fb97 | 67 | return tt; |
85f2b082 | 68 | |
bac5fb97 | 69 | list_for_each_entry_rcu(data, &file->triggers, list) { |
104f2810 TZ |
70 | if (data->paused) |
71 | continue; | |
bac5fb97 | 72 | if (!rec) { |
fb339e53 | 73 | data->ops->trigger(data, buffer, rec, event); |
bac5fb97 TZ |
74 | continue; |
75 | } | |
561a4fe8 | 76 | filter = rcu_dereference_sched(data->filter); |
d8a30f20 | 77 | if (filter && !filter_match_preds(filter, rec)) |
bac5fb97 | 78 | continue; |
353206f5 | 79 | if (event_command_post_trigger(data->cmd_ops)) { |
bac5fb97 TZ |
80 | tt |= data->cmd_ops->trigger_type; |
81 | continue; | |
82 | } | |
fb339e53 | 83 | data->ops->trigger(data, buffer, rec, event); |
bac5fb97 TZ |
84 | } |
85 | return tt; | |
85f2b082 TZ |
86 | } |
87 | EXPORT_SYMBOL_GPL(event_triggers_call); | |
88 | ||
bc82c38a CL |
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(file); | |
99 | return false; | |
100 | } | |
101 | EXPORT_SYMBOL_GPL(__trace_trigger_soft_disabled); | |
102 | ||
bac5fb97 TZ |
103 | /** |
104 | * event_triggers_post_call - Call 'post_triggers' for a trace event | |
7f1d2f82 | 105 | * @file: The trace_event_file associated with the event |
bac5fb97 TZ |
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 | |
7f1d2f82 | 116 | event_triggers_post_call(struct trace_event_file *file, |
c94e45bc | 117 | enum event_trigger_type tt) |
bac5fb97 TZ |
118 | { |
119 | struct event_trigger_data *data; | |
120 | ||
121 | list_for_each_entry_rcu(data, &file->triggers, list) { | |
104f2810 TZ |
122 | if (data->paused) |
123 | continue; | |
bac5fb97 | 124 | if (data->cmd_ops->trigger_type & tt) |
fb339e53 | 125 | data->ops->trigger(data, NULL, NULL, NULL); |
bac5fb97 TZ |
126 | } |
127 | } | |
128 | EXPORT_SYMBOL_GPL(event_triggers_post_call); | |
129 | ||
dd97b954 SRRH |
130 | #define SHOW_AVAILABLE_TRIGGERS (void *)(1UL) |
131 | ||
85f2b082 TZ |
132 | static void *trigger_next(struct seq_file *m, void *t, loff_t *pos) |
133 | { | |
7f1d2f82 | 134 | struct trace_event_file *event_file = event_file_data(m->private); |
85f2b082 | 135 | |
6722b23e VA |
136 | if (t == SHOW_AVAILABLE_TRIGGERS) { |
137 | (*pos)++; | |
dd97b954 | 138 | return NULL; |
6722b23e | 139 | } |
85f2b082 TZ |
140 | return seq_list_next(t, &event_file->triggers, pos); |
141 | } | |
142 | ||
7491e2c4 TSV |
143 | static bool check_user_trigger(struct trace_event_file *file) |
144 | { | |
145 | struct event_trigger_data *data; | |
146 | ||
cecf8e12 MHG |
147 | list_for_each_entry_rcu(data, &file->triggers, list, |
148 | lockdep_is_held(&event_mutex)) { | |
7491e2c4 TSV |
149 | if (data->flags & EVENT_TRIGGER_FL_PROBE) |
150 | continue; | |
151 | return true; | |
152 | } | |
153 | return false; | |
154 | } | |
155 | ||
85f2b082 TZ |
156 | static void *trigger_start(struct seq_file *m, loff_t *pos) |
157 | { | |
7f1d2f82 | 158 | struct trace_event_file *event_file; |
85f2b082 TZ |
159 | |
160 | /* ->stop() is called even if ->start() fails */ | |
161 | mutex_lock(&event_mutex); | |
b1560408 | 162 | event_file = event_file_file(m->private); |
85f2b082 TZ |
163 | if (unlikely(!event_file)) |
164 | return ERR_PTR(-ENODEV); | |
165 | ||
7491e2c4 | 166 | if (list_empty(&event_file->triggers) || !check_user_trigger(event_file)) |
dd97b954 SRRH |
167 | return *pos == 0 ? SHOW_AVAILABLE_TRIGGERS : NULL; |
168 | ||
85f2b082 TZ |
169 | return seq_list_start(&event_file->triggers, *pos); |
170 | } | |
171 | ||
172 | static void trigger_stop(struct seq_file *m, void *t) | |
173 | { | |
174 | mutex_unlock(&event_mutex); | |
175 | } | |
176 | ||
177 | static int trigger_show(struct seq_file *m, void *v) | |
178 | { | |
179 | struct event_trigger_data *data; | |
dd97b954 SRRH |
180 | struct event_command *p; |
181 | ||
182 | if (v == SHOW_AVAILABLE_TRIGGERS) { | |
183 | seq_puts(m, "# Available triggers:\n"); | |
184 | seq_putc(m, '#'); | |
185 | mutex_lock(&trigger_cmd_mutex); | |
186 | list_for_each_entry_reverse(p, &trigger_commands, list) | |
187 | seq_printf(m, " %s", p->name); | |
188 | seq_putc(m, '\n'); | |
189 | mutex_unlock(&trigger_cmd_mutex); | |
190 | return 0; | |
191 | } | |
85f2b082 TZ |
192 | |
193 | data = list_entry(v, struct event_trigger_data, list); | |
47670541 | 194 | data->ops->print(m, data); |
85f2b082 TZ |
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 | { | |
17911ff3 SRV |
208 | int ret; |
209 | ||
210 | ret = security_locked_down(LOCKDOWN_TRACEFS); | |
211 | if (ret) | |
212 | return ret; | |
85f2b082 TZ |
213 | |
214 | mutex_lock(&event_mutex); | |
215 | ||
b1560408 | 216 | if (unlikely(!event_file_file(file))) { |
85f2b082 TZ |
217 | mutex_unlock(&event_mutex); |
218 | return -ENODEV; | |
219 | } | |
220 | ||
a88e1cfb TZ |
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(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 | ||
85f2b082 TZ |
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(&event_mutex); | |
243 | ||
244 | return ret; | |
245 | } | |
246 | ||
81a59555 | 247 | int trigger_process_regex(struct trace_event_file *file, char *buff) |
85f2b082 | 248 | { |
6784bead | 249 | char *command, *next; |
85f2b082 TZ |
250 | struct event_command *p; |
251 | int ret = -EINVAL; | |
252 | ||
6784bead | 253 | next = buff = skip_spaces(buff); |
85f2b082 | 254 | command = strsep(&next, ": \t"); |
6784bead MH |
255 | if (next) { |
256 | next = skip_spaces(next); | |
257 | if (!*next) | |
258 | next = NULL; | |
259 | } | |
85f2b082 TZ |
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) { | |
9ec5a7d1 | 265 | ret = p->parse(p, file, buff, command, next); |
85f2b082 TZ |
266 | goto out_unlock; |
267 | } | |
268 | } | |
269 | out_unlock: | |
270 | mutex_unlock(&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 | { | |
7f1d2f82 | 279 | struct trace_event_file *event_file; |
85f2b082 TZ |
280 | ssize_t ret; |
281 | char *buf; | |
282 | ||
283 | if (!cnt) | |
284 | return 0; | |
285 | ||
286 | if (cnt >= PAGE_SIZE) | |
287 | return -EINVAL; | |
288 | ||
70f6cbb6 AV |
289 | buf = memdup_user_nul(ubuf, cnt); |
290 | if (IS_ERR(buf)) | |
291 | return PTR_ERR(buf); | |
85f2b082 | 292 | |
85f2b082 TZ |
293 | strim(buf); |
294 | ||
295 | mutex_lock(&event_mutex); | |
b1560408 | 296 | event_file = event_file_file(file); |
85f2b082 TZ |
297 | if (unlikely(!event_file)) { |
298 | mutex_unlock(&event_mutex); | |
70f6cbb6 | 299 | kfree(buf); |
85f2b082 TZ |
300 | return -ENODEV; |
301 | } | |
302 | ret = trigger_process_regex(event_file, buf); | |
303 | mutex_unlock(&event_mutex); | |
304 | ||
70f6cbb6 | 305 | kfree(buf); |
85f2b082 TZ |
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(&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(filp, ubuf, cnt, ppos); | |
332 | } | |
333 | ||
334 | static int | |
335 | event_trigger_open(struct inode *inode, struct file *filp) | |
336 | { | |
17911ff3 | 337 | /* Checks for tracefs lockdown */ |
85f2b082 TZ |
338 | return event_trigger_regex_open(inode, 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, | |
098c879e | 351 | .llseek = tracing_lseek, |
85f2b082 TZ |
352 | .release = event_trigger_release, |
353 | }; | |
354 | ||
2a2df321 TZ |
355 | /* |
356 | * Currently we only register event commands from __init, so mark this | |
357 | * __init too. | |
358 | */ | |
ab4bf008 | 359 | __init int register_event_command(struct event_command *cmd) |
2a2df321 TZ |
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(&cmd->list, &trigger_commands); | |
372 | out_unlock: | |
373 | mutex_unlock(&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 | */ | |
d0bad49b | 382 | __init int unregister_event_command(struct event_command *cmd) |
2a2df321 TZ |
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(&p->list); | |
392 | goto out_unlock; | |
393 | } | |
394 | } | |
395 | out_unlock: | |
396 | mutex_unlock(&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 | ||
fa6f0cc7 | 421 | seq_puts(m, name); |
2a2df321 TZ |
422 | |
423 | if (count == -1) | |
424 | seq_puts(m, ":unlimited"); | |
425 | else | |
426 | seq_printf(m, ":count=%ld", count); | |
427 | ||
428 | if (filter_str) | |
429 | seq_printf(m, " if %s\n", filter_str); | |
430 | else | |
1177e436 | 431 | seq_putc(m, '\n'); |
2a2df321 TZ |
432 | |
433 | return 0; | |
434 | } | |
435 | ||
436 | /** | |
437 | * event_trigger_init - Generic event_trigger_ops @init implementation | |
2a2df321 TZ |
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 | */ | |
47670541 | 447 | int event_trigger_init(struct event_trigger_data *data) |
2a2df321 TZ |
448 | { |
449 | data->ref++; | |
450 | return 0; | |
451 | } | |
452 | ||
453 | /** | |
454 | * event_trigger_free - Generic event_trigger_ops @free implementation | |
2a2df321 TZ |
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 | |
47670541 | 463 | event_trigger_free(struct event_trigger_data *data) |
2a2df321 TZ |
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 | ||
ab4bf008 TZ |
473 | int trace_event_trigger_enable_disable(struct trace_event_file *file, |
474 | int trigger_enable) | |
85f2b082 TZ |
475 | { |
476 | int ret = 0; | |
477 | ||
478 | if (trigger_enable) { | |
479 | if (atomic_inc_return(&file->tm_ref) > 1) | |
480 | return ret; | |
5d6ad960 | 481 | set_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags); |
85f2b082 TZ |
482 | ret = trace_event_enable_disable(file, 1, 1); |
483 | } else { | |
484 | if (atomic_dec_return(&file->tm_ref) > 0) | |
485 | return ret; | |
5d6ad960 | 486 | clear_bit(EVENT_FILE_FL_TRIGGER_MODE_BIT, &file->flags); |
85f2b082 TZ |
487 | ret = trace_event_enable_disable(file, 0, 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 | { | |
7f1d2f82 | 509 | struct trace_event_file *file; |
85f2b082 TZ |
510 | |
511 | list_for_each_entry(file, &tr->events, list) { | |
86b389ff SRV |
512 | struct event_trigger_data *data, *n; |
513 | list_for_each_entry_safe(data, n, &file->triggers, list) { | |
85f2b082 | 514 | trace_event_trigger_enable_disable(file, 0); |
86b389ff | 515 | list_del_rcu(&data->list); |
85f2b082 | 516 | if (data->ops->free) |
47670541 | 517 | data->ops->free(data); |
85f2b082 TZ |
518 | } |
519 | } | |
520 | } | |
521 | ||
bac5fb97 TZ |
522 | /** |
523 | * update_cond_flag - Set or reset the TRIGGER_COND bit | |
7f1d2f82 | 524 | * @file: The trace_event_file associated with the event |
bac5fb97 TZ |
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 | */ | |
ab4bf008 | 532 | void update_cond_flag(struct trace_event_file *file) |
bac5fb97 TZ |
533 | { |
534 | struct event_trigger_data *data; | |
535 | bool set_cond = false; | |
536 | ||
3b42a4c8 MH |
537 | lockdep_assert_held(&event_mutex); |
538 | ||
539 | list_for_each_entry(data, &file->triggers, list) { | |
353206f5 SRRH |
540 | if (data->filter || event_command_post_trigger(data->cmd_ops) || |
541 | event_command_needs_rec(data->cmd_ops)) { | |
bac5fb97 TZ |
542 | set_cond = true; |
543 | break; | |
544 | } | |
545 | } | |
546 | ||
547 | if (set_cond) | |
5d6ad960 | 548 | set_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags); |
bac5fb97 | 549 | else |
5d6ad960 | 550 | clear_bit(EVENT_FILE_FL_TRIGGER_COND_BIT, &file->flags); |
bac5fb97 TZ |
551 | } |
552 | ||
2a2df321 TZ |
553 | /** |
554 | * register_trigger - Generic event_command @reg implementation | |
555 | * @glob: The raw string used to register the trigger | |
2a2df321 | 556 | * @data: Trigger-specific data to associate with the trigger |
7f1d2f82 | 557 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
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 | */ | |
2378a2d6 | 566 | static int register_trigger(char *glob, |
2a2df321 | 567 | struct event_trigger_data *data, |
7f1d2f82 | 568 | struct trace_event_file *file) |
2a2df321 TZ |
569 | { |
570 | struct event_trigger_data *test; | |
571 | int ret = 0; | |
572 | ||
3b42a4c8 MH |
573 | lockdep_assert_held(&event_mutex); |
574 | ||
575 | list_for_each_entry(test, &file->triggers, list) { | |
2a2df321 TZ |
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) { | |
47670541 | 583 | ret = data->ops->init(data); |
2a2df321 TZ |
584 | if (ret < 0) |
585 | goto out; | |
586 | } | |
587 | ||
588 | list_add_rcu(&data->list, &file->triggers); | |
2a2df321 | 589 | |
4e4a4d75 | 590 | update_cond_flag(file); |
b8cc44a4 TZ |
591 | ret = trace_event_trigger_enable_disable(file, 1); |
592 | if (ret < 0) { | |
2a2df321 | 593 | list_del_rcu(&data->list); |
4e4a4d75 | 594 | update_cond_flag(file); |
2a2df321 TZ |
595 | } |
596 | out: | |
597 | return ret; | |
598 | } | |
599 | ||
180e4e39 VD |
600 | /* |
601 | * True if the trigger was found and unregistered, else false. | |
2a2df321 | 602 | */ |
180e4e39 VD |
603 | static bool try_unregister_trigger(char *glob, |
604 | struct event_trigger_data *test, | |
605 | struct trace_event_file *file) | |
2a2df321 | 606 | { |
45e333ce | 607 | struct event_trigger_data *data = NULL, *iter; |
2a2df321 | 608 | |
3b42a4c8 MH |
609 | lockdep_assert_held(&event_mutex); |
610 | ||
45e333ce JK |
611 | list_for_each_entry(iter, &file->triggers, list) { |
612 | if (iter->cmd_ops->trigger_type == test->cmd_ops->trigger_type) { | |
613 | data = iter; | |
2a2df321 TZ |
614 | list_del_rcu(&data->list); |
615 | trace_event_trigger_enable_disable(file, 0); | |
4e4a4d75 | 616 | update_cond_flag(file); |
2a2df321 TZ |
617 | break; |
618 | } | |
619 | } | |
620 | ||
180e4e39 VD |
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); | |
2a2df321 TZ |
647 | } |
648 | ||
86599dbe TZ |
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 | |
8d4a21b5 | 760 | * @param_and_filter: String containing trigger and possibly filter |
761 | * @param: outparam, will be filled with a pointer to the trigger | |
86599dbe TZ |
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 | |
8d4a21b5 | 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 | |
86599dbe TZ |
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(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(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(&trigger_data->list); | |
863 | INIT_LIST_HEAD(&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(number, 0, &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 | |
86599dbe | 943 | * @trigger_data: The trigger_data for the trigger |
86599dbe TZ |
944 | * |
945 | * Register an event trigger. The @cmd_ops are used to call the | |
b8cc44a4 | 946 | * cmd_ops->reg() function which actually does the registration. |
86599dbe TZ |
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, | |
b8cc44a4 | 953 | struct event_trigger_data *trigger_data) |
86599dbe | 954 | { |
b8cc44a4 TZ |
955 | return cmd_ops->reg(glob, trigger_data, file); |
956 | } | |
86599dbe | 957 | |
b8cc44a4 TZ |
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); | |
86599dbe TZ |
974 | } |
975 | ||
976 | /* | |
977 | * End event trigger parsing helper functions. | |
978 | */ | |
979 | ||
2a2df321 | 980 | /** |
9ec5a7d1 | 981 | * event_trigger_parse - Generic event_command @parse implementation |
2a2df321 | 982 | * @cmd_ops: The command ops, used for trigger registration |
7f1d2f82 | 983 | * @file: The trace_event_file associated with the event |
2a2df321 TZ |
984 | * @glob: The raw string used to register the trigger |
985 | * @cmd: The cmd portion of the string used to register the trigger | |
e1f187d0 | 986 | * @param_and_filter: The param and filter portion of the string used to register the trigger |
2a2df321 TZ |
987 | * |
988 | * Common implementation for event command parsing and trigger | |
989 | * instantiation. | |
990 | * | |
9ec5a7d1 | 991 | * Usually used directly as the @parse method in event command |
2a2df321 TZ |
992 | * implementations. |
993 | * | |
994 | * Return: 0 on success, errno otherwise | |
995 | */ | |
996 | static int | |
9ec5a7d1 TZ |
997 | event_trigger_parse(struct event_command *cmd_ops, |
998 | struct trace_event_file *file, | |
e1f187d0 | 999 | char *glob, char *cmd, char *param_and_filter) |
2a2df321 TZ |
1000 | { |
1001 | struct event_trigger_data *trigger_data; | |
e1f187d0 TZ |
1002 | char *param, *filter; |
1003 | bool remove; | |
2a2df321 TZ |
1004 | int ret; |
1005 | ||
e1f187d0 | 1006 | remove = event_trigger_check_remove(glob); |
2a2df321 | 1007 | |
e1f187d0 TZ |
1008 | ret = event_trigger_separate_filter(param_and_filter, ¶m, &filter, false); |
1009 | if (ret) | |
1010 | return ret; | |
2a2df321 TZ |
1011 | |
1012 | ret = -ENOMEM; | |
e1f187d0 | 1013 | trigger_data = event_trigger_alloc(cmd_ops, cmd, param, file); |
2a2df321 TZ |
1014 | if (!trigger_data) |
1015 | goto out; | |
1016 | ||
e1f187d0 | 1017 | if (remove) { |
b8cc44a4 | 1018 | event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); |
2a2df321 TZ |
1019 | kfree(trigger_data); |
1020 | ret = 0; | |
1021 | goto out; | |
1022 | } | |
1023 | ||
e1f187d0 TZ |
1024 | ret = event_trigger_parse_num(param, trigger_data); |
1025 | if (ret) | |
1026 | goto out_free; | |
2a2df321 | 1027 | |
e1f187d0 | 1028 | ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data); |
2a2df321 TZ |
1029 | if (ret < 0) |
1030 | goto out_free; | |
1031 | ||
1863c387 | 1032 | /* Up the trigger_data count to make sure reg doesn't free it on failure */ |
47670541 | 1033 | event_trigger_init(trigger_data); |
b8cc44a4 TZ |
1034 | |
1035 | ret = event_trigger_register(cmd_ops, file, glob, trigger_data); | |
1036 | if (ret) | |
1037 | goto out_free; | |
1863c387 SRV |
1038 | |
1039 | /* Down the counter of trigger_data or free it if not used anymore */ | |
47670541 | 1040 | event_trigger_free(trigger_data); |
2a2df321 TZ |
1041 | out: |
1042 | return ret; | |
1043 | ||
1044 | out_free: | |
e1f187d0 | 1045 | event_trigger_reset_filter(cmd_ops, trigger_data); |
2a2df321 TZ |
1046 | kfree(trigger_data); |
1047 | goto out; | |
1048 | } | |
1049 | ||
bac5fb97 TZ |
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 | |
7f1d2f82 | 1054 | * @file: The trace_event_file associated with the event |
bac5fb97 TZ |
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 | */ | |
ab4bf008 TZ |
1066 | int set_trigger_filter(char *filter_str, |
1067 | struct event_trigger_data *trigger_data, | |
1068 | struct trace_event_file *file) | |
bac5fb97 TZ |
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 */ | |
1e144d73 | 1087 | ret = create_event_filter(file->tr, file->event_call, |
a785736d SRG |
1088 | filter_str, true, &filter); |
1089 | ||
1090 | /* Only enabled set_str for error handling */ | |
1091 | if (filter) { | |
1092 | kfree(filter->filter_string); | |
1093 | filter->filter_string = NULL; | |
1094 | } | |
1095 | ||
3cec638b SRV |
1096 | /* |
1097 | * If create_event_filter() fails, filter still needs to be freed. | |
1098 | * Which the calling code will do with data->filter. | |
1099 | */ | |
bac5fb97 | 1100 | assign: |
d8a30f20 | 1101 | tmp = rcu_access_pointer(data->filter); |
bac5fb97 TZ |
1102 | |
1103 | rcu_assign_pointer(data->filter, filter); | |
1104 | ||
1105 | if (tmp) { | |
fb9f5ee9 SRG |
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(); | |
bac5fb97 TZ |
1114 | free_event_filter(tmp); |
1115 | } | |
1116 | ||
1117 | kfree(data->filter_str); | |
1118 | data->filter_str = NULL; | |
1119 | ||
1120 | if (filter_str) { | |
1121 | data->filter_str = kstrdup(filter_str, GFP_KERNEL); | |
1122 | if (!data->filter_str) { | |
d8a30f20 | 1123 | free_event_filter(rcu_access_pointer(data->filter)); |
bac5fb97 TZ |
1124 | data->filter = NULL; |
1125 | ret = -ENOMEM; | |
1126 | } | |
1127 | } | |
1128 | out: | |
1129 | return ret; | |
1130 | } | |
1131 | ||
db1388b4 TZ |
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(name, GFP_KERNEL); | |
1193 | if (!data->name) | |
1194 | return -ENOMEM; | |
1195 | ||
1196 | list_add(&data->named_list, &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(data->name); | |
1208 | data->name = NULL; | |
1209 | ||
1210 | list_del(&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, 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, false); | |
1255 | } | |
1256 | ||
1257 | /** | |
1258 | * set_named_trigger_data - Associate common named trigger data | |
099dcc18 QH |
1259 | * @data: The trigger data to associate |
1260 | * @named_data: The common named trigger to be associated | |
db1388b4 TZ |
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 | ||
067fe038 TZ |
1275 | struct event_trigger_data * |
1276 | get_named_trigger_data(struct event_trigger_data *data) | |
1277 | { | |
1278 | return data->named_data; | |
1279 | } | |
1280 | ||
2a2df321 | 1281 | static void |
b47e3302 SRV |
1282 | traceon_trigger(struct event_trigger_data *data, |
1283 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 1284 | struct ring_buffer_event *event) |
2a2df321 | 1285 | { |
302e9edd SRG |
1286 | struct trace_event_file *file = data->private_data; |
1287 | ||
1288 | if (file) { | |
1289 | if (tracer_tracing_is_on(file->tr)) | |
1290 | return; | |
1291 | ||
1292 | tracer_tracing_on(file->tr); | |
1293 | return; | |
1294 | } | |
1295 | ||
2a2df321 TZ |
1296 | if (tracing_is_on()) |
1297 | return; | |
1298 | ||
1299 | tracing_on(); | |
1300 | } | |
1301 | ||
1302 | static void | |
b47e3302 SRV |
1303 | traceon_count_trigger(struct event_trigger_data *data, |
1304 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 1305 | struct ring_buffer_event *event) |
2a2df321 | 1306 | { |
302e9edd SRG |
1307 | struct trace_event_file *file = data->private_data; |
1308 | ||
1309 | if (file) { | |
1310 | if (tracer_tracing_is_on(file->tr)) | |
1311 | return; | |
1312 | } else { | |
1313 | if (tracing_is_on()) | |
1314 | return; | |
1315 | } | |
e8dc6371 | 1316 | |
2a2df321 TZ |
1317 | if (!data->count) |
1318 | return; | |
1319 | ||
1320 | if (data->count != -1) | |
1321 | (data->count)--; | |
1322 | ||
302e9edd SRG |
1323 | if (file) |
1324 | tracer_tracing_on(file->tr); | |
1325 | else | |
1326 | tracing_on(); | |
2a2df321 TZ |
1327 | } |
1328 | ||
1329 | static void | |
b47e3302 SRV |
1330 | traceoff_trigger(struct event_trigger_data *data, |
1331 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 1332 | struct ring_buffer_event *event) |
2a2df321 | 1333 | { |
302e9edd SRG |
1334 | struct trace_event_file *file = data->private_data; |
1335 | ||
1336 | if (file) { | |
1337 | if (!tracer_tracing_is_on(file->tr)) | |
1338 | return; | |
1339 | ||
1340 | tracer_tracing_off(file->tr); | |
1341 | return; | |
1342 | } | |
1343 | ||
2a2df321 TZ |
1344 | if (!tracing_is_on()) |
1345 | return; | |
1346 | ||
1347 | tracing_off(); | |
1348 | } | |
1349 | ||
1350 | static void | |
b47e3302 SRV |
1351 | traceoff_count_trigger(struct event_trigger_data *data, |
1352 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 1353 | struct ring_buffer_event *event) |
2a2df321 | 1354 | { |
302e9edd SRG |
1355 | struct trace_event_file *file = data->private_data; |
1356 | ||
1357 | if (file) { | |
1358 | if (!tracer_tracing_is_on(file->tr)) | |
1359 | return; | |
1360 | } else { | |
1361 | if (!tracing_is_on()) | |
1362 | return; | |
1363 | } | |
e8dc6371 | 1364 | |
2a2df321 TZ |
1365 | if (!data->count) |
1366 | return; | |
1367 | ||
1368 | if (data->count != -1) | |
1369 | (data->count)--; | |
1370 | ||
302e9edd SRG |
1371 | if (file) |
1372 | tracer_tracing_off(file->tr); | |
1373 | else | |
1374 | tracing_off(); | |
2a2df321 TZ |
1375 | } |
1376 | ||
1377 | static int | |
47670541 | 1378 | traceon_trigger_print(struct seq_file *m, struct event_trigger_data *data) |
2a2df321 TZ |
1379 | { |
1380 | return event_trigger_print("traceon", m, (void *)data->count, | |
1381 | data->filter_str); | |
1382 | } | |
1383 | ||
1384 | static int | |
47670541 | 1385 | traceoff_trigger_print(struct seq_file *m, struct event_trigger_data *data) |
2a2df321 TZ |
1386 | { |
1387 | return event_trigger_print("traceoff", m, (void *)data->count, | |
1388 | data->filter_str); | |
1389 | } | |
1390 | ||
1391 | static struct event_trigger_ops traceon_trigger_ops = { | |
fb339e53 | 1392 | .trigger = traceon_trigger, |
2a2df321 TZ |
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 = { | |
fb339e53 | 1399 | .trigger = traceon_count_trigger, |
2a2df321 TZ |
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 = { | |
fb339e53 | 1406 | .trigger = traceoff_trigger, |
2a2df321 TZ |
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 = { | |
fb339e53 | 1413 | .trigger = traceoff_count_trigger, |
2a2df321 TZ |
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, | |
9ec5a7d1 | 1438 | .parse = event_trigger_parse, |
2a2df321 TZ |
1439 | .reg = register_trigger, |
1440 | .unreg = unregister_trigger, | |
1441 | .get_trigger_ops = onoff_get_trigger_ops, | |
bac5fb97 | 1442 | .set_filter = set_trigger_filter, |
2a2df321 TZ |
1443 | }; |
1444 | ||
1445 | static struct event_command trigger_traceoff_cmd = { | |
1446 | .name = "traceoff", | |
1447 | .trigger_type = ETT_TRACE_ONOFF, | |
a0d0c621 | 1448 | .flags = EVENT_CMD_FL_POST_TRIGGER, |
9ec5a7d1 | 1449 | .parse = event_trigger_parse, |
2a2df321 TZ |
1450 | .reg = register_trigger, |
1451 | .unreg = unregister_trigger, | |
1452 | .get_trigger_ops = onoff_get_trigger_ops, | |
bac5fb97 | 1453 | .set_filter = set_trigger_filter, |
2a2df321 TZ |
1454 | }; |
1455 | ||
93e31ffb TZ |
1456 | #ifdef CONFIG_TRACER_SNAPSHOT |
1457 | static void | |
b47e3302 SRV |
1458 | snapshot_trigger(struct event_trigger_data *data, |
1459 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 1460 | struct ring_buffer_event *event) |
93e31ffb | 1461 | { |
2824f503 SRV |
1462 | struct trace_event_file *file = data->private_data; |
1463 | ||
1464 | if (file) | |
1465 | tracing_snapshot_instance(file->tr); | |
1466 | else | |
1467 | tracing_snapshot(); | |
93e31ffb TZ |
1468 | } |
1469 | ||
1470 | static void | |
b47e3302 SRV |
1471 | snapshot_count_trigger(struct event_trigger_data *data, |
1472 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 1473 | struct ring_buffer_event *event) |
93e31ffb TZ |
1474 | { |
1475 | if (!data->count) | |
1476 | return; | |
1477 | ||
1478 | if (data->count != -1) | |
1479 | (data->count)--; | |
1480 | ||
b47e3302 | 1481 | snapshot_trigger(data, buffer, rec, event); |
93e31ffb TZ |
1482 | } |
1483 | ||
1484 | static int | |
2378a2d6 | 1485 | register_snapshot_trigger(char *glob, |
93e31ffb | 1486 | struct event_trigger_data *data, |
7f1d2f82 | 1487 | struct trace_event_file *file) |
93e31ffb | 1488 | { |
180e4e39 | 1489 | int ret = tracing_arm_snapshot(file->tr); |
0958b33e MHG |
1490 | |
1491 | if (ret < 0) | |
1492 | return ret; | |
93e31ffb | 1493 | |
2048fdc2 SRG |
1494 | ret = register_trigger(glob, data, file); |
1495 | if (ret < 0) | |
1496 | tracing_disarm_snapshot(file->tr); | |
1497 | return ret; | |
93e31ffb TZ |
1498 | } |
1499 | ||
180e4e39 VD |
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, data, file)) | |
1505 | tracing_disarm_snapshot(file->tr); | |
1506 | } | |
1507 | ||
93e31ffb | 1508 | static int |
47670541 | 1509 | snapshot_trigger_print(struct seq_file *m, struct event_trigger_data *data) |
93e31ffb TZ |
1510 | { |
1511 | return event_trigger_print("snapshot", m, (void *)data->count, | |
1512 | data->filter_str); | |
1513 | } | |
1514 | ||
1515 | static struct event_trigger_ops snapshot_trigger_ops = { | |
fb339e53 | 1516 | .trigger = snapshot_trigger, |
93e31ffb TZ |
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 = { | |
fb339e53 | 1523 | .trigger = snapshot_count_trigger, |
93e31ffb TZ |
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, | |
9ec5a7d1 | 1538 | .parse = event_trigger_parse, |
93e31ffb | 1539 | .reg = register_snapshot_trigger, |
180e4e39 | 1540 | .unreg = unregister_snapshot_trigger, |
93e31ffb | 1541 | .get_trigger_ops = snapshot_get_trigger_ops, |
bac5fb97 | 1542 | .set_filter = set_trigger_filter, |
93e31ffb TZ |
1543 | }; |
1544 | ||
1545 | static __init int register_trigger_snapshot_cmd(void) | |
1546 | { | |
1547 | int ret; | |
1548 | ||
1549 | ret = register_event_command(&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 | ||
f21ecbb3 | 1558 | #ifdef CONFIG_STACKTRACE |
2ee5b92a SRV |
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 | |
f21ecbb3 | 1566 | /* |
2ee5b92a | 1567 | * Skip 4: |
f21ecbb3 TZ |
1568 | * stacktrace_trigger() |
1569 | * event_triggers_post_call() | |
2ee5b92a | 1570 | * trace_event_buffer_commit() |
a7237765 | 1571 | * trace_event_raw_event_xxx() |
f21ecbb3 | 1572 | */ |
2ee5b92a SRV |
1573 | #define STACK_SKIP 4 |
1574 | #endif | |
f21ecbb3 TZ |
1575 | |
1576 | static void | |
b47e3302 SRV |
1577 | stacktrace_trigger(struct event_trigger_data *data, |
1578 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 1579 | struct ring_buffer_event *event) |
f21ecbb3 | 1580 | { |
ce33c845 DBO |
1581 | struct trace_event_file *file = data->private_data; |
1582 | ||
1583 | if (file) | |
1584 | __trace_stack(file->tr, tracing_gen_ctx(), STACK_SKIP); | |
1585 | else | |
1586 | trace_dump_stack(STACK_SKIP); | |
f21ecbb3 TZ |
1587 | } |
1588 | ||
1589 | static void | |
b47e3302 SRV |
1590 | stacktrace_count_trigger(struct event_trigger_data *data, |
1591 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 1592 | struct ring_buffer_event *event) |
f21ecbb3 TZ |
1593 | { |
1594 | if (!data->count) | |
1595 | return; | |
1596 | ||
1597 | if (data->count != -1) | |
1598 | (data->count)--; | |
1599 | ||
b47e3302 | 1600 | stacktrace_trigger(data, buffer, rec, event); |
f21ecbb3 TZ |
1601 | } |
1602 | ||
1603 | static int | |
47670541 | 1604 | stacktrace_trigger_print(struct seq_file *m, struct event_trigger_data *data) |
f21ecbb3 TZ |
1605 | { |
1606 | return event_trigger_print("stacktrace", m, (void *)data->count, | |
1607 | data->filter_str); | |
1608 | } | |
1609 | ||
1610 | static struct event_trigger_ops stacktrace_trigger_ops = { | |
fb339e53 | 1611 | .trigger = stacktrace_trigger, |
f21ecbb3 TZ |
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 = { | |
fb339e53 | 1618 | .trigger = stacktrace_count_trigger, |
f21ecbb3 TZ |
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, | |
353206f5 | 1633 | .flags = EVENT_CMD_FL_POST_TRIGGER, |
9ec5a7d1 | 1634 | .parse = event_trigger_parse, |
f21ecbb3 TZ |
1635 | .reg = register_trigger, |
1636 | .unreg = unregister_trigger, | |
1637 | .get_trigger_ops = stacktrace_get_trigger_ops, | |
bac5fb97 | 1638 | .set_filter = set_trigger_filter, |
f21ecbb3 TZ |
1639 | }; |
1640 | ||
1641 | static __init int register_trigger_stacktrace_cmd(void) | |
1642 | { | |
1643 | int ret; | |
1644 | ||
1645 | ret = register_event_command(&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 | ||
2a2df321 TZ |
1654 | static __init void unregister_trigger_traceon_traceoff_cmds(void) |
1655 | { | |
1656 | unregister_event_command(&trigger_traceon_cmd); | |
1657 | unregister_event_command(&trigger_traceoff_cmd); | |
1658 | } | |
1659 | ||
7862ad18 | 1660 | static void |
b47e3302 SRV |
1661 | event_enable_trigger(struct event_trigger_data *data, |
1662 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 1663 | struct ring_buffer_event *event) |
7862ad18 TZ |
1664 | { |
1665 | struct enable_trigger_data *enable_data = data->private_data; | |
1666 | ||
1667 | if (enable_data->enable) | |
5d6ad960 | 1668 | clear_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); |
7862ad18 | 1669 | else |
5d6ad960 | 1670 | set_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &enable_data->file->flags); |
7862ad18 TZ |
1671 | } |
1672 | ||
1673 | static void | |
b47e3302 SRV |
1674 | event_enable_count_trigger(struct event_trigger_data *data, |
1675 | struct trace_buffer *buffer, void *rec, | |
1ac4f51c | 1676 | struct ring_buffer_event *event) |
7862ad18 TZ |
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 */ | |
5d6ad960 | 1684 | if (enable_data->enable == !(enable_data->file->flags & EVENT_FILE_FL_SOFT_DISABLED)) |
7862ad18 TZ |
1685 | return; |
1686 | ||
1687 | if (data->count != -1) | |
1688 | (data->count)--; | |
1689 | ||
b47e3302 | 1690 | event_enable_trigger(data, buffer, rec, event); |
7862ad18 TZ |
1691 | } |
1692 | ||
d0bad49b | 1693 | int event_enable_trigger_print(struct seq_file *m, |
d0bad49b | 1694 | struct event_trigger_data *data) |
7862ad18 TZ |
1695 | { |
1696 | struct enable_trigger_data *enable_data = data->private_data; | |
1697 | ||
1698 | seq_printf(m, "%s:%s:%s", | |
d0bad49b TZ |
1699 | enable_data->hist ? |
1700 | (enable_data->enable ? ENABLE_HIST_STR : DISABLE_HIST_STR) : | |
1701 | (enable_data->enable ? ENABLE_EVENT_STR : DISABLE_EVENT_STR), | |
7862ad18 | 1702 | enable_data->file->event_call->class->system, |
687fcc4a | 1703 | trace_event_name(enable_data->file->event_call)); |
7862ad18 TZ |
1704 | |
1705 | if (data->count == -1) | |
1706 | seq_puts(m, ":unlimited"); | |
1707 | else | |
1708 | seq_printf(m, ":count=%ld", data->count); | |
1709 | ||
1710 | if (data->filter_str) | |
1711 | seq_printf(m, " if %s\n", data->filter_str); | |
1712 | else | |
1177e436 | 1713 | seq_putc(m, '\n'); |
7862ad18 TZ |
1714 | |
1715 | return 0; | |
1716 | } | |
1717 | ||
47670541 | 1718 | void event_enable_trigger_free(struct event_trigger_data *data) |
7862ad18 TZ |
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(enable_data->file, 0, 1); | |
1d18538e | 1729 | trace_event_put_ref(enable_data->file->event_call); |
7862ad18 TZ |
1730 | trigger_data_free(data); |
1731 | kfree(enable_data); | |
1732 | } | |
1733 | } | |
1734 | ||
1735 | static struct event_trigger_ops event_enable_trigger_ops = { | |
fb339e53 | 1736 | .trigger = event_enable_trigger, |
7862ad18 TZ |
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 = { | |
fb339e53 | 1743 | .trigger = event_enable_count_trigger, |
7862ad18 TZ |
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 = { | |
fb339e53 | 1750 | .trigger = event_enable_trigger, |
7862ad18 TZ |
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 = { | |
fb339e53 | 1757 | .trigger = event_enable_count_trigger, |
7862ad18 TZ |
1758 | .print = event_enable_trigger_print, |
1759 | .init = event_trigger_init, | |
1760 | .free = event_enable_trigger_free, | |
1761 | }; | |
1762 | ||
9ec5a7d1 TZ |
1763 | int event_enable_trigger_parse(struct event_command *cmd_ops, |
1764 | struct trace_event_file *file, | |
e1f187d0 | 1765 | char *glob, char *cmd, char *param_and_filter) |
7862ad18 | 1766 | { |
7f1d2f82 | 1767 | struct trace_event_file *event_enable_file; |
7862ad18 TZ |
1768 | struct enable_trigger_data *enable_data; |
1769 | struct event_trigger_data *trigger_data; | |
7862ad18 | 1770 | struct trace_array *tr = file->tr; |
e1f187d0 TZ |
1771 | char *param, *filter; |
1772 | bool enable, remove; | |
7862ad18 TZ |
1773 | const char *system; |
1774 | const char *event; | |
d0bad49b | 1775 | bool hist = false; |
7862ad18 TZ |
1776 | int ret; |
1777 | ||
e1f187d0 | 1778 | remove = event_trigger_check_remove(glob); |
7862ad18 | 1779 | |
e1f187d0 | 1780 | if (event_trigger_empty_param(param_and_filter)) |
7862ad18 TZ |
1781 | return -EINVAL; |
1782 | ||
e1f187d0 TZ |
1783 | ret = event_trigger_separate_filter(param_and_filter, ¶m, &filter, true); |
1784 | if (ret) | |
1785 | return ret; | |
1786 | ||
1787 | system = strsep(¶m, ":"); | |
1788 | if (!param) | |
7862ad18 TZ |
1789 | return -EINVAL; |
1790 | ||
e1f187d0 | 1791 | event = strsep(¶m, ":"); |
7862ad18 TZ |
1792 | |
1793 | ret = -EINVAL; | |
1794 | event_enable_file = find_event_file(tr, system, event); | |
1795 | if (!event_enable_file) | |
1796 | goto out; | |
1797 | ||
d0bad49b TZ |
1798 | #ifdef CONFIG_HIST_TRIGGERS |
1799 | hist = ((strcmp(cmd, ENABLE_HIST_STR) == 0) || | |
1800 | (strcmp(cmd, DISABLE_HIST_STR) == 0)); | |
7862ad18 | 1801 | |
d0bad49b TZ |
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 | |
7862ad18 | 1807 | ret = -ENOMEM; |
7862ad18 TZ |
1808 | |
1809 | enable_data = kzalloc(sizeof(*enable_data), GFP_KERNEL); | |
e1f187d0 | 1810 | if (!enable_data) |
7862ad18 | 1811 | goto out; |
7862ad18 | 1812 | |
d0bad49b | 1813 | enable_data->hist = hist; |
7862ad18 TZ |
1814 | enable_data->enable = enable; |
1815 | enable_data->file = event_enable_file; | |
7862ad18 | 1816 | |
e1f187d0 TZ |
1817 | trigger_data = event_trigger_alloc(cmd_ops, cmd, param, enable_data); |
1818 | if (!trigger_data) { | |
1819 | kfree(enable_data); | |
1820 | goto out; | |
1821 | } | |
1822 | ||
1823 | if (remove) { | |
b8cc44a4 | 1824 | event_trigger_unregister(cmd_ops, file, glob+1, trigger_data); |
7862ad18 TZ |
1825 | kfree(trigger_data); |
1826 | kfree(enable_data); | |
1827 | ret = 0; | |
1828 | goto out; | |
1829 | } | |
1830 | ||
15cc7864 | 1831 | /* Up the trigger_data count to make sure nothing frees it on failure */ |
47670541 | 1832 | event_trigger_init(trigger_data); |
15cc7864 | 1833 | |
e1f187d0 TZ |
1834 | ret = event_trigger_parse_num(param, trigger_data); |
1835 | if (ret) | |
1836 | goto out_free; | |
7862ad18 | 1837 | |
e1f187d0 | 1838 | ret = event_trigger_set_filter(cmd_ops, file, filter, trigger_data); |
7862ad18 TZ |
1839 | if (ret < 0) |
1840 | goto out_free; | |
1841 | ||
7862ad18 | 1842 | /* Don't let event modules unload while probe registered */ |
1d18538e | 1843 | ret = trace_event_try_get_ref(event_enable_file->event_call); |
7862ad18 TZ |
1844 | if (!ret) { |
1845 | ret = -EBUSY; | |
1846 | goto out_free; | |
1847 | } | |
1848 | ||
1849 | ret = trace_event_enable_disable(event_enable_file, 1, 1); | |
1850 | if (ret < 0) | |
1851 | goto out_put; | |
b8cc44a4 TZ |
1852 | |
1853 | ret = event_trigger_register(cmd_ops, file, glob, trigger_data); | |
1854 | if (ret) | |
7862ad18 | 1855 | goto out_disable; |
b8cc44a4 | 1856 | |
47670541 | 1857 | event_trigger_free(trigger_data); |
7862ad18 TZ |
1858 | out: |
1859 | return ret; | |
7862ad18 TZ |
1860 | out_disable: |
1861 | trace_event_enable_disable(event_enable_file, 0, 1); | |
1862 | out_put: | |
1d18538e | 1863 | trace_event_put_ref(event_enable_file->event_call); |
7862ad18 | 1864 | out_free: |
e1f187d0 | 1865 | event_trigger_reset_filter(cmd_ops, trigger_data); |
47670541 | 1866 | event_trigger_free(trigger_data); |
7862ad18 | 1867 | kfree(enable_data); |
e1f187d0 | 1868 | |
7862ad18 TZ |
1869 | goto out; |
1870 | } | |
1871 | ||
d0bad49b | 1872 | int event_enable_register_trigger(char *glob, |
d0bad49b TZ |
1873 | struct event_trigger_data *data, |
1874 | struct trace_event_file *file) | |
7862ad18 TZ |
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 | ||
3b42a4c8 MH |
1881 | lockdep_assert_held(&event_mutex); |
1882 | ||
1883 | list_for_each_entry(test, &file->triggers, list) { | |
7862ad18 TZ |
1884 | test_enable_data = test->private_data; |
1885 | if (test_enable_data && | |
d0bad49b TZ |
1886 | (test->cmd_ops->trigger_type == |
1887 | data->cmd_ops->trigger_type) && | |
7862ad18 TZ |
1888 | (test_enable_data->file == enable_data->file)) { |
1889 | ret = -EEXIST; | |
1890 | goto out; | |
1891 | } | |
1892 | } | |
1893 | ||
1894 | if (data->ops->init) { | |
47670541 | 1895 | ret = data->ops->init(data); |
7862ad18 TZ |
1896 | if (ret < 0) |
1897 | goto out; | |
1898 | } | |
1899 | ||
1900 | list_add_rcu(&data->list, &file->triggers); | |
7862ad18 | 1901 | |
4e4a4d75 | 1902 | update_cond_flag(file); |
b8cc44a4 TZ |
1903 | ret = trace_event_trigger_enable_disable(file, 1); |
1904 | if (ret < 0) { | |
7862ad18 | 1905 | list_del_rcu(&data->list); |
4e4a4d75 | 1906 | update_cond_flag(file); |
7862ad18 TZ |
1907 | } |
1908 | out: | |
1909 | return ret; | |
1910 | } | |
1911 | ||
d0bad49b | 1912 | void event_enable_unregister_trigger(char *glob, |
d0bad49b TZ |
1913 | struct event_trigger_data *test, |
1914 | struct trace_event_file *file) | |
7862ad18 TZ |
1915 | { |
1916 | struct enable_trigger_data *test_enable_data = test->private_data; | |
45e333ce | 1917 | struct event_trigger_data *data = NULL, *iter; |
7862ad18 | 1918 | struct enable_trigger_data *enable_data; |
7862ad18 | 1919 | |
3b42a4c8 MH |
1920 | lockdep_assert_held(&event_mutex); |
1921 | ||
45e333ce JK |
1922 | list_for_each_entry(iter, &file->triggers, list) { |
1923 | enable_data = iter->private_data; | |
7862ad18 | 1924 | if (enable_data && |
45e333ce | 1925 | (iter->cmd_ops->trigger_type == |
d0bad49b | 1926 | test->cmd_ops->trigger_type) && |
7862ad18 | 1927 | (enable_data->file == test_enable_data->file)) { |
45e333ce | 1928 | data = iter; |
7862ad18 TZ |
1929 | list_del_rcu(&data->list); |
1930 | trace_event_trigger_enable_disable(file, 0); | |
4e4a4d75 | 1931 | update_cond_flag(file); |
7862ad18 TZ |
1932 | break; |
1933 | } | |
1934 | } | |
1935 | ||
45e333ce | 1936 | if (data && data->ops->free) |
47670541 | 1937 | data->ops->free(data); |
7862ad18 TZ |
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 | ||
d0bad49b TZ |
1946 | #ifdef CONFIG_HIST_TRIGGERS |
1947 | enable = ((strcmp(cmd, ENABLE_EVENT_STR) == 0) || | |
1948 | (strcmp(cmd, ENABLE_HIST_STR) == 0)); | |
1949 | #else | |
7862ad18 | 1950 | enable = strcmp(cmd, ENABLE_EVENT_STR) == 0; |
d0bad49b | 1951 | #endif |
7862ad18 TZ |
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, | |
9ec5a7d1 | 1965 | .parse = event_enable_trigger_parse, |
7862ad18 TZ |
1966 | .reg = event_enable_register_trigger, |
1967 | .unreg = event_enable_unregister_trigger, | |
1968 | .get_trigger_ops = event_enable_get_trigger_ops, | |
bac5fb97 | 1969 | .set_filter = set_trigger_filter, |
7862ad18 TZ |
1970 | }; |
1971 | ||
1972 | static struct event_command trigger_disable_cmd = { | |
1973 | .name = DISABLE_EVENT_STR, | |
1974 | .trigger_type = ETT_EVENT_ENABLE, | |
9ec5a7d1 | 1975 | .parse = event_enable_trigger_parse, |
7862ad18 TZ |
1976 | .reg = event_enable_register_trigger, |
1977 | .unreg = event_enable_unregister_trigger, | |
1978 | .get_trigger_ops = event_enable_get_trigger_ops, | |
bac5fb97 | 1979 | .set_filter = set_trigger_filter, |
7862ad18 TZ |
1980 | }; |
1981 | ||
1982 | static __init void unregister_trigger_enable_disable_cmds(void) | |
1983 | { | |
1984 | unregister_event_command(&trigger_enable_cmd); | |
1985 | unregister_event_command(&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(&trigger_enable_cmd); | |
1993 | if (WARN_ON(ret < 0)) | |
1994 | return ret; | |
1995 | ret = register_event_command(&trigger_disable_cmd); | |
1996 | if (WARN_ON(ret < 0)) | |
1997 | unregister_trigger_enable_disable_cmds(); | |
1998 | ||
1999 | return ret; | |
2000 | } | |
2001 | ||
2a2df321 TZ |
2002 | static __init int register_trigger_traceon_traceoff_cmds(void) |
2003 | { | |
2004 | int ret; | |
2005 | ||
2006 | ret = register_event_command(&trigger_traceon_cmd); | |
2007 | if (WARN_ON(ret < 0)) | |
2008 | return ret; | |
2009 | ret = register_event_command(&trigger_traceoff_cmd); | |
2010 | if (WARN_ON(ret < 0)) | |
2011 | unregister_trigger_traceon_traceoff_cmds(); | |
2012 | ||
2013 | return ret; | |
2014 | } | |
2015 | ||
85f2b082 TZ |
2016 | __init int register_trigger_cmds(void) |
2017 | { | |
2a2df321 | 2018 | register_trigger_traceon_traceoff_cmds(); |
93e31ffb | 2019 | register_trigger_snapshot_cmd(); |
f21ecbb3 | 2020 | register_trigger_stacktrace_cmd(); |
7862ad18 | 2021 | register_trigger_enable_disable_cmds(); |
d0bad49b | 2022 | register_trigger_hist_enable_disable_cmds(); |
7ef224d1 | 2023 | register_trigger_hist_cmd(); |
2a2df321 | 2024 | |
85f2b082 TZ |
2025 | return 0; |
2026 | } |