projects / lttng-modules.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
Drop 'linux/file.h' wrapper
[lttng-modules.git] / src / lttng-events.c
1 /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
2 *
3 * lttng-events.c
4 *
5 * Holds LTTng per-session event registry.
6 *
7 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
8 */
9
10 /*
11 * This page_alloc.h wrapper needs to be included before gfpflags.h because it
12 * overrides a function with a define.
13 */
14 #include "wrapper/page_alloc.h"
15
16 #include <linux/module.h>
17 #include <linux/mutex.h>
18 #include <linux/sched.h>
19 #include <linux/slab.h>
20 #include <linux/jiffies.h>
21 #include <linux/utsname.h>
22 #include <linux/err.h>
23 #include <linux/seq_file.h>
24 #include <linux/file.h>
25 #include <linux/anon_inodes.h>
26 #include <linux/uaccess.h>
27 #include <linux/vmalloc.h>
28 #include <linux/dmi.h>
29
30 #include <wrapper/compiler_attributes.h>
31 #include <wrapper/uuid.h>
32 #include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
33 #include <wrapper/random.h>
34 #include <wrapper/tracepoint.h>
35 #include <wrapper/list.h>
36 #include <wrapper/types.h>
37 #include <lttng/kernel-version.h>
38 #include <lttng/events.h>
39 #include <lttng/events-internal.h>
40 #include <lttng/lttng-bytecode.h>
41 #include <lttng/tracer.h>
42 #include <lttng/event-notifier-notification.h>
43 #include <lttng/abi-old.h>
44 #include <lttng/endian.h>
45 #include <lttng/string-utils.h>
46 #include <lttng/utils.h>
47 #include <ringbuffer/backend.h>
48 #include <ringbuffer/frontend.h>
49 #include <wrapper/time.h>
50
51 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,16,0))
52 #include <linux/stdarg.h>
53 #else
54 #include <stdarg.h>
55 #endif
56
57 #define METADATA_CACHE_DEFAULT_SIZE 4096
58
59 static LIST_HEAD(sessions);
60 static LIST_HEAD(event_notifier_groups);
61 static LIST_HEAD(lttng_transport_list);
62 static LIST_HEAD(lttng_counter_transport_list);
63 /*
64 * Protect the sessions and metadata caches.
65 */
66 static DEFINE_MUTEX(sessions_mutex);
67 static struct kmem_cache *event_recorder_cache;
68 static struct kmem_cache *event_recorder_private_cache;
69 static struct kmem_cache *event_notifier_cache;
70 static struct kmem_cache *event_notifier_private_cache;
71
72 static void lttng_session_lazy_sync_event_enablers(struct lttng_kernel_session *session);
73 static void lttng_session_sync_event_enablers(struct lttng_kernel_session *session);
74 static void lttng_event_notifier_group_sync_enablers(struct lttng_event_notifier_group *event_notifier_group);
75 static void lttng_event_enabler_sync(struct lttng_event_enabler_common *event_enabler);
76
77 static void _lttng_event_destroy(struct lttng_kernel_event_common *event);
78 static void _lttng_channel_destroy(struct lttng_kernel_channel_buffer *chan);
79 static void _lttng_event_unregister(struct lttng_kernel_event_common *event);
80 static
81 int _lttng_event_recorder_metadata_statedump(struct lttng_kernel_event_common *event);
82 static
83 int _lttng_session_metadata_statedump(struct lttng_kernel_session *session);
84 static
85 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream);
86 static
87 int _lttng_type_statedump(struct lttng_kernel_session *session,
88 const struct lttng_kernel_type_common *type,
89 enum lttng_kernel_string_encoding parent_encoding,
90 size_t nesting);
91 static
92 int _lttng_field_statedump(struct lttng_kernel_session *session,
93 const struct lttng_kernel_event_field *field,
94 size_t nesting, const char **prev_field_name_p);
95
96 void synchronize_trace(void)
97 {
98 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,1,0) || \
99 LTTNG_RHEL_KERNEL_RANGE(4,18,0,193,0,0, 4,19,0,0,0,0))
100 synchronize_rcu();
101 #else
102 synchronize_sched();
103 #endif
104
105 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0))
106 #ifdef CONFIG_PREEMPT_RT_FULL
107 synchronize_rcu();
108 #endif
109 #else /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
110 #ifdef CONFIG_PREEMPT_RT
111 synchronize_rcu();
112 #endif
113 #endif /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
114 }
115
116 void lttng_lock_sessions(void)
117 {
118 mutex_lock(&sessions_mutex);
119 }
120
121 void lttng_unlock_sessions(void)
122 {
123 mutex_unlock(&sessions_mutex);
124 }
125
126 static struct lttng_transport *lttng_transport_find(const char *name)
127 {
128 struct lttng_transport *transport;
129
130 list_for_each_entry(transport, &lttng_transport_list, node) {
131 if (!strcmp(transport->name, name))
132 return transport;
133 }
134 return NULL;
135 }
136
137 /*
138 * Called with sessions lock held.
139 */
140 int lttng_session_active(void)
141 {
142 struct lttng_kernel_session_private *iter;
143
144 list_for_each_entry(iter, &sessions, list) {
145 if (iter->pub->active)
146 return 1;
147 }
148 return 0;
149 }
150
151 struct lttng_kernel_session *lttng_session_create(void)
152 {
153 struct lttng_kernel_session *session;
154 struct lttng_kernel_session_private *session_priv;
155 struct lttng_metadata_cache *metadata_cache;
156 int i;
157
158 mutex_lock(&sessions_mutex);
159 session = lttng_kvzalloc(sizeof(*session), GFP_KERNEL);
160 if (!session)
161 goto err;
162 session_priv = lttng_kvzalloc(sizeof(*session_priv), GFP_KERNEL);
163 if (!session_priv)
164 goto err_free_session;
165 session->priv = session_priv;
166 session_priv->pub = session;
167
168 INIT_LIST_HEAD(&session_priv->chan);
169 INIT_LIST_HEAD(&session_priv->events);
170 lttng_guid_gen(&session_priv->uuid);
171
172 metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache),
173 GFP_KERNEL);
174 if (!metadata_cache)
175 goto err_free_session_private;
176 metadata_cache->data = vzalloc(METADATA_CACHE_DEFAULT_SIZE);
177 if (!metadata_cache->data)
178 goto err_free_cache;
179 metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE;
180 kref_init(&metadata_cache->refcount);
181 mutex_init(&metadata_cache->lock);
182 session_priv->metadata_cache = metadata_cache;
183 INIT_LIST_HEAD(&metadata_cache->metadata_stream);
184 memcpy(&metadata_cache->uuid, &session_priv->uuid,
185 sizeof(metadata_cache->uuid));
186 INIT_LIST_HEAD(&session_priv->enablers_head);
187 for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
188 INIT_HLIST_HEAD(&session_priv->events_ht.table[i]);
189 list_add(&session_priv->list, &sessions);
190
191 if (lttng_id_tracker_init(&session->pid_tracker, session, TRACKER_PID))
192 goto tracker_alloc_error;
193 if (lttng_id_tracker_init(&session->vpid_tracker, session, TRACKER_VPID))
194 goto tracker_alloc_error;
195 if (lttng_id_tracker_init(&session->uid_tracker, session, TRACKER_UID))
196 goto tracker_alloc_error;
197 if (lttng_id_tracker_init(&session->vuid_tracker, session, TRACKER_VUID))
198 goto tracker_alloc_error;
199 if (lttng_id_tracker_init(&session->gid_tracker, session, TRACKER_GID))
200 goto tracker_alloc_error;
201 if (lttng_id_tracker_init(&session->vgid_tracker, session, TRACKER_VGID))
202 goto tracker_alloc_error;
203
204 mutex_unlock(&sessions_mutex);
205
206 return session;
207
208 tracker_alloc_error:
209 lttng_id_tracker_fini(&session->pid_tracker);
210 lttng_id_tracker_fini(&session->vpid_tracker);
211 lttng_id_tracker_fini(&session->uid_tracker);
212 lttng_id_tracker_fini(&session->vuid_tracker);
213 lttng_id_tracker_fini(&session->gid_tracker);
214 lttng_id_tracker_fini(&session->vgid_tracker);
215 err_free_cache:
216 kfree(metadata_cache);
217 err_free_session_private:
218 lttng_kvfree(session_priv);
219 err_free_session:
220 lttng_kvfree(session);
221 err:
222 mutex_unlock(&sessions_mutex);
223 return NULL;
224 }
225
226 static
227 struct lttng_counter_transport *lttng_counter_transport_find(const char *name)
228 {
229 struct lttng_counter_transport *transport;
230
231 list_for_each_entry(transport, &lttng_counter_transport_list, node) {
232 if (!strcmp(transport->name, name))
233 return transport;
234 }
235 return NULL;
236 }
237
238 struct lttng_counter *lttng_kernel_counter_create(
239 const char *counter_transport_name,
240 size_t number_dimensions, const size_t *dimensions_sizes)
241 {
242 struct lttng_counter *counter = NULL;
243 struct lttng_counter_transport *counter_transport = NULL;
244
245 counter_transport = lttng_counter_transport_find(counter_transport_name);
246 if (!counter_transport) {
247 printk(KERN_WARNING "LTTng: counter transport %s not found.\n",
248 counter_transport_name);
249 goto notransport;
250 }
251 if (!try_module_get(counter_transport->owner)) {
252 printk(KERN_WARNING "LTTng: Can't lock counter transport module.\n");
253 goto notransport;
254 }
255
256 counter = lttng_kvzalloc(sizeof(struct lttng_counter), GFP_KERNEL);
257 if (!counter)
258 goto nomem;
259
260 /* Create event notifier error counter. */
261 counter->ops = &counter_transport->ops;
262 counter->transport = counter_transport;
263
264 counter->counter = counter->ops->counter_create(
265 number_dimensions, dimensions_sizes, 0);
266 if (!counter->counter) {
267 goto create_error;
268 }
269
270 return counter;
271
272 create_error:
273 lttng_kvfree(counter);
274 nomem:
275 if (counter_transport)
276 module_put(counter_transport->owner);
277 notransport:
278 return NULL;
279 }
280
281 struct lttng_event_notifier_group *lttng_event_notifier_group_create(void)
282 {
283 struct lttng_transport *transport = NULL;
284 struct lttng_event_notifier_group *event_notifier_group;
285 const char *transport_name = "relay-event-notifier";
286 size_t subbuf_size = 4096; //TODO
287 size_t num_subbuf = 16; //TODO
288 unsigned int switch_timer_interval = 0;
289 unsigned int read_timer_interval = 0;
290 int i;
291
292 mutex_lock(&sessions_mutex);
293
294 transport = lttng_transport_find(transport_name);
295 if (!transport) {
296 printk(KERN_WARNING "LTTng: transport %s not found\n",
297 transport_name);
298 goto notransport;
299 }
300 if (!try_module_get(transport->owner)) {
301 printk(KERN_WARNING "LTTng: Can't lock transport %s module.\n",
302 transport_name);
303 goto notransport;
304 }
305
306 event_notifier_group = lttng_kvzalloc(sizeof(struct lttng_event_notifier_group),
307 GFP_KERNEL);
308 if (!event_notifier_group)
309 goto nomem;
310
311 /*
312 * Initialize the ring buffer used to store event notifier
313 * notifications.
314 */
315 event_notifier_group->ops = &transport->ops;
316 event_notifier_group->chan = transport->ops.priv->channel_create(
317 transport_name, event_notifier_group, NULL,
318 subbuf_size, num_subbuf, switch_timer_interval,
319 read_timer_interval);
320 if (!event_notifier_group->chan)
321 goto create_error;
322
323 event_notifier_group->transport = transport;
324
325 INIT_LIST_HEAD(&event_notifier_group->enablers_head);
326 INIT_LIST_HEAD(&event_notifier_group->event_notifiers_head);
327 for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
328 INIT_HLIST_HEAD(&event_notifier_group->events_ht.table[i]);
329
330 list_add(&event_notifier_group->node, &event_notifier_groups);
331
332 mutex_unlock(&sessions_mutex);
333
334 return event_notifier_group;
335
336 create_error:
337 lttng_kvfree(event_notifier_group);
338 nomem:
339 if (transport)
340 module_put(transport->owner);
341 notransport:
342 mutex_unlock(&sessions_mutex);
343 return NULL;
344 }
345
346 void metadata_cache_destroy(struct kref *kref)
347 {
348 struct lttng_metadata_cache *cache =
349 container_of(kref, struct lttng_metadata_cache, refcount);
350 vfree(cache->data);
351 kfree(cache);
352 }
353
354 void lttng_session_destroy(struct lttng_kernel_session *session)
355 {
356 struct lttng_kernel_channel_buffer_private *chan_priv, *tmpchan_priv;
357 struct lttng_kernel_event_recorder_private *event_recorder_priv, *tmpevent_recorder_priv;
358 struct lttng_metadata_stream *metadata_stream;
359 struct lttng_event_enabler_common *event_enabler, *tmp_event_enabler;
360 int ret;
361
362 mutex_lock(&sessions_mutex);
363 WRITE_ONCE(session->active, 0);
364 list_for_each_entry(chan_priv, &session->priv->chan, node) {
365 ret = lttng_syscalls_unregister_syscall_table(&chan_priv->parent.syscall_table);
366 WARN_ON(ret);
367 }
368 list_for_each_entry(event_recorder_priv, &session->priv->events, parent.node)
369 _lttng_event_unregister(&event_recorder_priv->pub->parent);
370 synchronize_trace(); /* Wait for in-flight events to complete */
371 list_for_each_entry(chan_priv, &session->priv->chan, node) {
372 ret = lttng_syscalls_destroy_syscall_table(&chan_priv->parent.syscall_table);
373 WARN_ON(ret);
374 }
375 list_for_each_entry_safe(event_enabler, tmp_event_enabler, &session->priv->enablers_head, node)
376 lttng_event_enabler_destroy(event_enabler);
377 list_for_each_entry_safe(event_recorder_priv, tmpevent_recorder_priv, &session->priv->events, parent.node)
378 _lttng_event_destroy(&event_recorder_priv->pub->parent);
379 list_for_each_entry_safe(chan_priv, tmpchan_priv, &session->priv->chan, node) {
380 BUG_ON(chan_priv->channel_type == METADATA_CHANNEL);
381 _lttng_channel_destroy(chan_priv->pub);
382 }
383 mutex_lock(&session->priv->metadata_cache->lock);
384 list_for_each_entry(metadata_stream, &session->priv->metadata_cache->metadata_stream, list)
385 _lttng_metadata_channel_hangup(metadata_stream);
386 mutex_unlock(&session->priv->metadata_cache->lock);
387 lttng_id_tracker_fini(&session->pid_tracker);
388 lttng_id_tracker_fini(&session->vpid_tracker);
389 lttng_id_tracker_fini(&session->uid_tracker);
390 lttng_id_tracker_fini(&session->vuid_tracker);
391 lttng_id_tracker_fini(&session->gid_tracker);
392 lttng_id_tracker_fini(&session->vgid_tracker);
393 kref_put(&session->priv->metadata_cache->refcount, metadata_cache_destroy);
394 list_del(&session->priv->list);
395 mutex_unlock(&sessions_mutex);
396 lttng_kvfree(session->priv);
397 lttng_kvfree(session);
398 }
399
400 void lttng_event_notifier_group_destroy(
401 struct lttng_event_notifier_group *event_notifier_group)
402 {
403 struct lttng_event_enabler_common *event_enabler, *tmp_event_enabler;
404 struct lttng_kernel_event_notifier_private *event_notifier_priv, *tmpevent_notifier_priv;
405 int ret;
406
407 if (!event_notifier_group)
408 return;
409
410 mutex_lock(&sessions_mutex);
411
412 ret = lttng_syscalls_unregister_syscall_table(&event_notifier_group->syscall_table);
413 WARN_ON(ret);
414
415 list_for_each_entry_safe(event_notifier_priv, tmpevent_notifier_priv,
416 &event_notifier_group->event_notifiers_head, parent.node)
417 _lttng_event_unregister(&event_notifier_priv->pub->parent);
418
419 /* Wait for in-flight event notifier to complete */
420 synchronize_trace();
421
422 irq_work_sync(&event_notifier_group->wakeup_pending);
423
424 ret = lttng_syscalls_destroy_syscall_table(&event_notifier_group->syscall_table);
425 WARN_ON(ret);
426
427 list_for_each_entry_safe(event_enabler, tmp_event_enabler,
428 &event_notifier_group->enablers_head, node)
429 lttng_event_enabler_destroy(event_enabler);
430
431 list_for_each_entry_safe(event_notifier_priv, tmpevent_notifier_priv,
432 &event_notifier_group->event_notifiers_head, parent.node)
433 _lttng_event_destroy(&event_notifier_priv->pub->parent);
434
435 if (event_notifier_group->error_counter) {
436 struct lttng_counter *error_counter = event_notifier_group->error_counter;
437
438 error_counter->ops->counter_destroy(error_counter->counter);
439 module_put(error_counter->transport->owner);
440 lttng_kvfree(error_counter);
441 event_notifier_group->error_counter = NULL;
442 }
443
444 event_notifier_group->ops->priv->channel_destroy(event_notifier_group->chan);
445 module_put(event_notifier_group->transport->owner);
446 list_del(&event_notifier_group->node);
447
448 mutex_unlock(&sessions_mutex);
449 lttng_kvfree(event_notifier_group);
450 }
451
452 int lttng_session_statedump(struct lttng_kernel_session *session)
453 {
454 int ret;
455
456 mutex_lock(&sessions_mutex);
457 ret = lttng_statedump_start(session);
458 mutex_unlock(&sessions_mutex);
459 return ret;
460 }
461
462 int lttng_session_enable(struct lttng_kernel_session *session)
463 {
464 int ret = 0;
465 struct lttng_kernel_channel_buffer_private *chan_priv;
466
467 mutex_lock(&sessions_mutex);
468 if (session->active) {
469 ret = -EBUSY;
470 goto end;
471 }
472
473 /* Set transient enabler state to "enabled" */
474 session->priv->tstate = 1;
475
476 /* We need to sync enablers with session before activation. */
477 lttng_session_sync_event_enablers(session);
478
479 /*
480 * Snapshot the number of events per channel to know the type of header
481 * we need to use.
482 */
483 list_for_each_entry(chan_priv, &session->priv->chan, node) {
484 if (chan_priv->header_type)
485 continue; /* don't change it if session stop/restart */
486 if (chan_priv->free_event_id < 31)
487 chan_priv->header_type = 1; /* compact */
488 else
489 chan_priv->header_type = 2; /* large */
490 }
491
492 /* Clear each stream's quiescent state. */
493 list_for_each_entry(chan_priv, &session->priv->chan, node) {
494 if (chan_priv->channel_type != METADATA_CHANNEL)
495 lib_ring_buffer_clear_quiescent_channel(chan_priv->rb_chan);
496 }
497
498 WRITE_ONCE(session->active, 1);
499 WRITE_ONCE(session->priv->been_active, 1);
500 ret = _lttng_session_metadata_statedump(session);
501 if (ret) {
502 WRITE_ONCE(session->active, 0);
503 goto end;
504 }
505 ret = lttng_statedump_start(session);
506 if (ret)
507 WRITE_ONCE(session->active, 0);
508 end:
509 mutex_unlock(&sessions_mutex);
510 return ret;
511 }
512
513 int lttng_session_disable(struct lttng_kernel_session *session)
514 {
515 int ret = 0;
516 struct lttng_kernel_channel_buffer_private *chan_priv;
517
518 mutex_lock(&sessions_mutex);
519 if (!session->active) {
520 ret = -EBUSY;
521 goto end;
522 }
523 WRITE_ONCE(session->active, 0);
524
525 /* Set transient enabler state to "disabled" */
526 session->priv->tstate = 0;
527 lttng_session_sync_event_enablers(session);
528
529 /* Set each stream's quiescent state. */
530 list_for_each_entry(chan_priv, &session->priv->chan, node) {
531 if (chan_priv->channel_type != METADATA_CHANNEL)
532 lib_ring_buffer_set_quiescent_channel(chan_priv->rb_chan);
533 }
534 end:
535 mutex_unlock(&sessions_mutex);
536 return ret;
537 }
538
539 int lttng_session_metadata_regenerate(struct lttng_kernel_session *session)
540 {
541 int ret = 0;
542 struct lttng_kernel_channel_buffer_private *chan_priv;
543 struct lttng_kernel_event_recorder_private *event_recorder_priv;
544 struct lttng_metadata_cache *cache = session->priv->metadata_cache;
545 struct lttng_metadata_stream *stream;
546
547 mutex_lock(&sessions_mutex);
548 if (!session->active) {
549 ret = -EBUSY;
550 goto end;
551 }
552
553 mutex_lock(&cache->lock);
554 memset(cache->data, 0, cache->cache_alloc);
555 cache->metadata_written = 0;
556 cache->version++;
557 list_for_each_entry(stream, &session->priv->metadata_cache->metadata_stream, list) {
558 stream->metadata_out = 0;
559 stream->metadata_in = 0;
560 }
561 mutex_unlock(&cache->lock);
562
563 session->priv->metadata_dumped = 0;
564 list_for_each_entry(chan_priv, &session->priv->chan, node) {
565 chan_priv->metadata_dumped = 0;
566 }
567
568 list_for_each_entry(event_recorder_priv, &session->priv->events, parent.node) {
569 event_recorder_priv->metadata_dumped = 0;
570 }
571
572 ret = _lttng_session_metadata_statedump(session);
573
574 end:
575 mutex_unlock(&sessions_mutex);
576 return ret;
577 }
578
579 static
580 bool is_channel_buffer_metadata(struct lttng_kernel_channel_common *channel)
581 {
582 struct lttng_kernel_channel_buffer *chan_buf;
583
584 if (channel->type != LTTNG_KERNEL_CHANNEL_TYPE_BUFFER)
585 return false;
586 chan_buf = container_of(channel, struct lttng_kernel_channel_buffer, parent);
587 if (chan_buf->priv->channel_type == METADATA_CHANNEL)
588 return true;
589 return false;
590 }
591
592 int lttng_channel_enable(struct lttng_kernel_channel_common *channel)
593 {
594 int ret = 0;
595
596 mutex_lock(&sessions_mutex);
597 if (is_channel_buffer_metadata(channel)) {
598 ret = -EPERM;
599 goto end;
600 }
601 if (channel->enabled) {
602 ret = -EEXIST;
603 goto end;
604 }
605 /* Set transient enabler state to "enabled" */
606 channel->priv->tstate = 1;
607 lttng_session_sync_event_enablers(channel->session);
608 /* Set atomically the state to "enabled" */
609 WRITE_ONCE(channel->enabled, 1);
610 end:
611 mutex_unlock(&sessions_mutex);
612 return ret;
613 }
614
615 int lttng_channel_disable(struct lttng_kernel_channel_common *channel)
616 {
617 int ret = 0;
618
619 mutex_lock(&sessions_mutex);
620 if (is_channel_buffer_metadata(channel)) {
621 ret = -EPERM;
622 goto end;
623 }
624 if (!channel->enabled) {
625 ret = -EEXIST;
626 goto end;
627 }
628 /* Set atomically the state to "disabled" */
629 WRITE_ONCE(channel->enabled, 0);
630 /* Set transient enabler state to "enabled" */
631 channel->priv->tstate = 0;
632 lttng_session_sync_event_enablers(channel->session);
633 end:
634 mutex_unlock(&sessions_mutex);
635 return ret;
636 }
637
638 int lttng_event_enable(struct lttng_kernel_event_common *event)
639 {
640 int ret = 0;
641
642 mutex_lock(&sessions_mutex);
643 switch (event->type) {
644 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
645 {
646 struct lttng_kernel_event_recorder *event_recorder =
647 container_of(event, struct lttng_kernel_event_recorder, parent);
648
649 if (event_recorder->chan->priv->channel_type == METADATA_CHANNEL) {
650 ret = -EPERM;
651 goto end;
652 }
653 break;
654 }
655 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
656 switch (event->priv->instrumentation) {
657 case LTTNG_KERNEL_ABI_KRETPROBE:
658 ret = -EINVAL;
659 goto end;
660 default:
661 break;
662 }
663 break;
664 default:
665 break;
666 }
667
668 if (event->enabled) {
669 ret = -EEXIST;
670 goto end;
671 }
672 switch (event->priv->instrumentation) {
673 case LTTNG_KERNEL_ABI_TRACEPOINT:
674 lttng_fallthrough;
675 case LTTNG_KERNEL_ABI_SYSCALL:
676 ret = -EINVAL;
677 break;
678
679 case LTTNG_KERNEL_ABI_KPROBE:
680 lttng_fallthrough;
681 case LTTNG_KERNEL_ABI_UPROBE:
682 WRITE_ONCE(event->enabled, 1);
683 break;
684
685 case LTTNG_KERNEL_ABI_KRETPROBE:
686 ret = lttng_kretprobes_event_enable_state(event, 1);
687 break;
688
689 case LTTNG_KERNEL_ABI_FUNCTION:
690 lttng_fallthrough;
691 case LTTNG_KERNEL_ABI_NOOP:
692 lttng_fallthrough;
693 default:
694 WARN_ON_ONCE(1);
695 ret = -EINVAL;
696 }
697 end:
698 mutex_unlock(&sessions_mutex);
699 return ret;
700 }
701
702 int lttng_event_disable(struct lttng_kernel_event_common *event)
703 {
704 int ret = 0;
705
706 mutex_lock(&sessions_mutex);
707 switch (event->type) {
708 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
709 {
710 struct lttng_kernel_event_recorder *event_recorder =
711 container_of(event, struct lttng_kernel_event_recorder, parent);
712
713 if (event_recorder->chan->priv->channel_type == METADATA_CHANNEL) {
714 ret = -EPERM;
715 goto end;
716 }
717 break;
718 }
719 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
720 switch (event->priv->instrumentation) {
721 case LTTNG_KERNEL_ABI_KRETPROBE:
722 ret = -EINVAL;
723 goto end;
724 default:
725 break;
726 }
727 break;
728 default:
729 break;
730 }
731
732 if (!event->enabled) {
733 ret = -EEXIST;
734 goto end;
735 }
736 switch (event->priv->instrumentation) {
737 case LTTNG_KERNEL_ABI_TRACEPOINT:
738 lttng_fallthrough;
739 case LTTNG_KERNEL_ABI_SYSCALL:
740 ret = -EINVAL;
741 break;
742
743 case LTTNG_KERNEL_ABI_KPROBE:
744 lttng_fallthrough;
745 case LTTNG_KERNEL_ABI_UPROBE:
746 WRITE_ONCE(event->enabled, 0);
747 break;
748
749 case LTTNG_KERNEL_ABI_KRETPROBE:
750 ret = lttng_kretprobes_event_enable_state(event, 0);
751 break;
752
753 case LTTNG_KERNEL_ABI_FUNCTION:
754 lttng_fallthrough;
755 case LTTNG_KERNEL_ABI_NOOP:
756 lttng_fallthrough;
757 default:
758 WARN_ON_ONCE(1);
759 ret = -EINVAL;
760 }
761 end:
762 mutex_unlock(&sessions_mutex);
763 return ret;
764 }
765
766 struct lttng_kernel_channel_buffer *lttng_channel_buffer_create(struct lttng_kernel_session *session,
767 const char *transport_name,
768 void *buf_addr,
769 size_t subbuf_size, size_t num_subbuf,
770 unsigned int switch_timer_interval,
771 unsigned int read_timer_interval,
772 enum channel_type channel_type)
773 {
774 struct lttng_kernel_channel_buffer *chan;
775 struct lttng_kernel_channel_buffer_private *chan_priv;
776 struct lttng_transport *transport = NULL;
777
778 mutex_lock(&sessions_mutex);
779 if (session->priv->been_active && channel_type != METADATA_CHANNEL)
780 goto active; /* Refuse to add channel to active session */
781 transport = lttng_transport_find(transport_name);
782 if (!transport) {
783 printk(KERN_WARNING "LTTng: transport %s not found\n",
784 transport_name);
785 goto notransport;
786 }
787 if (!try_module_get(transport->owner)) {
788 printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
789 goto notransport;
790 }
791 chan = kzalloc(sizeof(struct lttng_kernel_channel_buffer), GFP_KERNEL);
792 if (!chan)
793 goto nomem;
794 chan_priv = kzalloc(sizeof(struct lttng_kernel_channel_buffer_private), GFP_KERNEL);
795 if (!chan_priv)
796 goto nomem_priv;
797 chan->priv = chan_priv;
798 chan_priv->pub = chan;
799 chan->parent.type = LTTNG_KERNEL_CHANNEL_TYPE_BUFFER;
800 chan->parent.session = session;
801 chan->priv->id = session->priv->free_chan_id++;
802 chan->ops = &transport->ops;
803 /*
804 * Note: the channel creation op already writes into the packet
805 * headers. Therefore the "chan" information used as input
806 * should be already accessible.
807 */
808 chan->priv->rb_chan = transport->ops.priv->channel_create(transport_name,
809 chan, buf_addr, subbuf_size, num_subbuf,
810 switch_timer_interval, read_timer_interval);
811 if (!chan->priv->rb_chan)
812 goto create_error;
813 chan->priv->parent.tstate = 1;
814 chan->parent.enabled = 1;
815 chan->priv->transport = transport;
816 chan->priv->channel_type = channel_type;
817 list_add(&chan->priv->node, &session->priv->chan);
818 mutex_unlock(&sessions_mutex);
819 return chan;
820
821 create_error:
822 kfree(chan_priv);
823 nomem_priv:
824 kfree(chan);
825 nomem:
826 if (transport)
827 module_put(transport->owner);
828 notransport:
829 active:
830 mutex_unlock(&sessions_mutex);
831 return NULL;
832 }
833
834 /*
835 * Only used internally at session destruction for per-cpu channels, and
836 * when metadata channel is released.
837 * Needs to be called with sessions mutex held.
838 */
839 static
840 void _lttng_channel_destroy(struct lttng_kernel_channel_buffer *chan)
841 {
842 chan->ops->priv->channel_destroy(chan->priv->rb_chan);
843 module_put(chan->priv->transport->owner);
844 list_del(&chan->priv->node);
845 lttng_kernel_destroy_context(chan->priv->ctx);
846 kfree(chan->priv);
847 kfree(chan);
848 }
849
850 void lttng_metadata_channel_destroy(struct lttng_kernel_channel_buffer *chan)
851 {
852 BUG_ON(chan->priv->channel_type != METADATA_CHANNEL);
853
854 /* Protect the metadata cache with the sessions_mutex. */
855 mutex_lock(&sessions_mutex);
856 _lttng_channel_destroy(chan);
857 mutex_unlock(&sessions_mutex);
858 }
859 EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy);
860
861 static
862 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream)
863 {
864 stream->finalized = 1;
865 wake_up_interruptible(&stream->read_wait);
866 }
867
868 static
869 bool lttng_kernel_event_id_available(struct lttng_event_enabler_common *event_enabler)
870 {
871 struct lttng_kernel_abi_event *event_param = &event_enabler->event_param;
872 enum lttng_kernel_abi_instrumentation itype = event_param->instrumentation;
873
874 switch (event_enabler->enabler_type) {
875 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
876 {
877 struct lttng_event_recorder_enabler *event_recorder_enabler =
878 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
879 struct lttng_kernel_channel_buffer *chan = event_recorder_enabler->chan;
880
881 switch (itype) {
882 case LTTNG_KERNEL_ABI_TRACEPOINT:
883 lttng_fallthrough;
884 case LTTNG_KERNEL_ABI_KPROBE:
885 lttng_fallthrough;
886 case LTTNG_KERNEL_ABI_SYSCALL:
887 lttng_fallthrough;
888 case LTTNG_KERNEL_ABI_UPROBE:
889 if (chan->priv->free_event_id == -1U)
890 return false;
891 return true;
892 case LTTNG_KERNEL_ABI_KRETPROBE:
893 /* kretprobes require 2 event IDs. */
894 if (chan->priv->free_event_id >= -2U)
895 return false;
896 return true;
897 default:
898 WARN_ON_ONCE(1);
899 return false;
900 }
901 }
902 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
903 return true;
904 default:
905 WARN_ON_ONCE(1);
906 return false;
907 }
908 }
909
910 static
911 struct lttng_kernel_event_common *lttng_kernel_event_alloc(struct lttng_event_enabler_common *event_enabler)
912 {
913 struct lttng_kernel_abi_event *event_param = &event_enabler->event_param;
914 enum lttng_kernel_abi_instrumentation itype = event_param->instrumentation;
915
916 switch (event_enabler->enabler_type) {
917 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
918 {
919 struct lttng_event_recorder_enabler *event_recorder_enabler =
920 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
921 struct lttng_kernel_event_recorder *event_recorder;
922 struct lttng_kernel_event_recorder_private *event_recorder_priv;
923 struct lttng_kernel_channel_buffer *chan = event_recorder_enabler->chan;
924
925 event_recorder = kmem_cache_zalloc(event_recorder_cache, GFP_KERNEL);
926 if (!event_recorder)
927 return NULL;
928 event_recorder_priv = kmem_cache_zalloc(event_recorder_private_cache, GFP_KERNEL);
929 if (!event_recorder_priv) {
930 kmem_cache_free(event_recorder_private_cache, event_recorder);
931 return NULL;
932 }
933 event_recorder_priv->pub = event_recorder;
934 event_recorder_priv->parent.pub = &event_recorder->parent;
935 event_recorder->priv = event_recorder_priv;
936 event_recorder->parent.priv = &event_recorder_priv->parent;
937
938 event_recorder->parent.type = LTTNG_KERNEL_EVENT_TYPE_RECORDER;
939 event_recorder->parent.run_filter = lttng_kernel_interpret_event_filter;
940 event_recorder->priv->parent.instrumentation = itype;
941 INIT_LIST_HEAD(&event_recorder->priv->parent.filter_bytecode_runtime_head);
942 INIT_LIST_HEAD(&event_recorder->priv->parent.enablers_ref_head);
943
944 event_recorder->chan = chan;
945 event_recorder->priv->id = chan->priv->free_event_id++;
946 return &event_recorder->parent;
947 }
948 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
949 {
950 struct lttng_event_notifier_enabler *event_notifier_enabler =
951 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
952 struct lttng_kernel_event_notifier *event_notifier;
953 struct lttng_kernel_event_notifier_private *event_notifier_priv;
954
955 event_notifier = kmem_cache_zalloc(event_notifier_cache, GFP_KERNEL);
956 if (!event_notifier)
957 return NULL;
958 event_notifier_priv = kmem_cache_zalloc(event_notifier_private_cache, GFP_KERNEL);
959 if (!event_notifier_priv) {
960 kmem_cache_free(event_notifier_private_cache, event_notifier);
961 return NULL;
962 }
963 event_notifier_priv->pub = event_notifier;
964 event_notifier_priv->parent.pub = &event_notifier->parent;
965 event_notifier->priv = event_notifier_priv;
966 event_notifier->parent.priv = &event_notifier_priv->parent;
967
968 event_notifier->parent.type = LTTNG_KERNEL_EVENT_TYPE_NOTIFIER;
969 event_notifier->parent.run_filter = lttng_kernel_interpret_event_filter;
970 event_notifier->priv->parent.instrumentation = itype;
971 event_notifier->priv->parent.user_token = event_enabler->user_token;
972 INIT_LIST_HEAD(&event_notifier->priv->parent.filter_bytecode_runtime_head);
973 INIT_LIST_HEAD(&event_notifier->priv->parent.enablers_ref_head);
974
975 event_notifier->priv->group = event_notifier_enabler->group;
976 event_notifier->priv->error_counter_index = event_notifier_enabler->error_counter_index;
977 event_notifier->priv->num_captures = 0;
978 event_notifier->notification_send = lttng_event_notifier_notification_send;
979 INIT_LIST_HEAD(&event_notifier->priv->capture_bytecode_runtime_head);
980 return &event_notifier->parent;
981 }
982 default:
983 return NULL;
984 }
985 }
986
987 static
988 void lttng_kernel_event_free(struct lttng_kernel_event_common *event)
989 {
990 switch (event->type) {
991 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
992 {
993 struct lttng_kernel_event_recorder *event_recorder =
994 container_of(event, struct lttng_kernel_event_recorder, parent);
995
996 kmem_cache_free(event_recorder_private_cache, event_recorder->priv);
997 kmem_cache_free(event_recorder_cache, event_recorder);
998 break;
999 }
1000 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1001 {
1002 struct lttng_kernel_event_notifier *event_notifier =
1003 container_of(event, struct lttng_kernel_event_notifier, parent);
1004
1005 kmem_cache_free(event_notifier_private_cache, event_notifier->priv);
1006 kmem_cache_free(event_notifier_cache, event_notifier);
1007 break;
1008 }
1009 default:
1010 WARN_ON_ONCE(1);
1011 }
1012 }
1013
1014 static
1015 int lttng_kernel_event_notifier_clear_error_counter(struct lttng_kernel_event_common *event)
1016 {
1017 switch (event->type) {
1018 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1019 return 0;
1020 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1021 {
1022 struct lttng_kernel_event_notifier *event_notifier =
1023 container_of(event, struct lttng_kernel_event_notifier, parent);
1024 struct lttng_counter *error_counter;
1025 struct lttng_event_notifier_group *event_notifier_group = event_notifier->priv->group;
1026 size_t dimension_index[1];
1027 int ret;
1028
1029 /*
1030 * Clear the error counter bucket. The sessiond keeps track of which
1031 * bucket is currently in use. We trust it. The session lock
1032 * synchronizes against concurrent creation of the error
1033 * counter.
1034 */
1035 error_counter = event_notifier_group->error_counter;
1036 if (!error_counter)
1037 return 0;
1038 /*
1039 * Check that the index is within the boundary of the counter.
1040 */
1041 if (event_notifier->priv->error_counter_index >= event_notifier_group->error_counter_len) {
1042 printk(KERN_INFO "LTTng: event_notifier: Error counter index out-of-bound: counter-len=%zu, index=%llu\n",
1043 event_notifier_group->error_counter_len, event_notifier->priv->error_counter_index);
1044 return -EINVAL;
1045 }
1046
1047 dimension_index[0] = event_notifier->priv->error_counter_index;
1048 ret = error_counter->ops->counter_clear(error_counter->counter, dimension_index);
1049 if (ret) {
1050 printk(KERN_INFO "LTTng: event_notifier: Unable to clear error counter bucket %llu\n",
1051 event_notifier->priv->error_counter_index);
1052 return -EINVAL;
1053 }
1054 return 0;
1055 }
1056 default:
1057 return -EINVAL;
1058 }
1059 }
1060
1061 /*
1062 * Supports event creation while tracing session is active.
1063 * Needs to be called with sessions mutex held.
1064 */
1065 struct lttng_kernel_event_common *_lttng_kernel_event_create(struct lttng_event_enabler_common *event_enabler,
1066 const struct lttng_kernel_event_desc *event_desc)
1067 {
1068 struct lttng_event_ht *events_ht = lttng_get_event_ht_from_enabler(event_enabler);
1069 struct list_head *event_list_head = lttng_get_event_list_head_from_enabler(event_enabler);
1070 struct lttng_kernel_abi_event *event_param = &event_enabler->event_param;
1071 enum lttng_kernel_abi_instrumentation itype = event_param->instrumentation;
1072 struct lttng_kernel_event_common_private *event_priv;
1073 struct lttng_kernel_event_common *event;
1074 const char *event_name;
1075 struct hlist_head *head;
1076 int ret;
1077
1078 if (!lttng_kernel_event_id_available(event_enabler)) {
1079 ret = -EMFILE;
1080 goto full;
1081 }
1082
1083 switch (itype) {
1084 case LTTNG_KERNEL_ABI_TRACEPOINT:
1085 event_name = event_desc->event_name;
1086 break;
1087
1088 case LTTNG_KERNEL_ABI_KPROBE:
1089 lttng_fallthrough;
1090 case LTTNG_KERNEL_ABI_UPROBE:
1091 lttng_fallthrough;
1092 case LTTNG_KERNEL_ABI_KRETPROBE:
1093 lttng_fallthrough;
1094 case LTTNG_KERNEL_ABI_SYSCALL:
1095 event_name = event_param->name;
1096 break;
1097
1098 case LTTNG_KERNEL_ABI_FUNCTION:
1099 lttng_fallthrough;
1100 case LTTNG_KERNEL_ABI_NOOP:
1101 lttng_fallthrough;
1102 default:
1103 WARN_ON_ONCE(1);
1104 ret = -EINVAL;
1105 goto type_error;
1106 }
1107
1108 head = utils_borrow_hash_table_bucket(events_ht->table, LTTNG_EVENT_HT_SIZE, event_name);
1109 lttng_hlist_for_each_entry(event_priv, head, hlist_node) {
1110 if (lttng_event_enabler_event_name_match_event(event_enabler, event_name, event_priv->pub)) {
1111 ret = -EEXIST;
1112 goto exist;
1113 }
1114 }
1115
1116 event = lttng_kernel_event_alloc(event_enabler);
1117 if (!event) {
1118 ret = -ENOMEM;
1119 goto alloc_error;
1120 }
1121
1122 switch (itype) {
1123 case LTTNG_KERNEL_ABI_TRACEPOINT:
1124 /* Event will be enabled by enabler sync. */
1125 event->enabled = 0;
1126 event->priv->registered = 0;
1127 event->priv->desc = lttng_event_desc_get(event_name);
1128 if (!event->priv->desc) {
1129 ret = -ENOENT;
1130 goto register_error;
1131 }
1132 /* Populate lttng_event structure before event registration. */
1133 smp_wmb();
1134 break;
1135
1136 case LTTNG_KERNEL_ABI_KPROBE:
1137 /*
1138 * Needs to be explicitly enabled after creation, since
1139 * we may want to apply filters.
1140 */
1141 event->enabled = 0;
1142 event->priv->registered = 1;
1143 /*
1144 * Populate lttng_event structure before event
1145 * registration.
1146 */
1147 smp_wmb();
1148 ret = lttng_kprobes_register_event(event_name,
1149 event_param->u.kprobe.symbol_name,
1150 event_param->u.kprobe.offset,
1151 event_param->u.kprobe.addr,
1152 event);
1153 if (ret) {
1154 ret = -EINVAL;
1155 goto register_error;
1156 }
1157 ret = try_module_get(event->priv->desc->owner);
1158 WARN_ON_ONCE(!ret);
1159 break;
1160
1161 case LTTNG_KERNEL_ABI_KRETPROBE:
1162 {
1163 struct lttng_kernel_event_common *event_return;
1164
1165 /* kretprobe defines 2 events */
1166 /*
1167 * Needs to be explicitly enabled after creation, since
1168 * we may want to apply filters.
1169 */
1170 event->enabled = 0;
1171 event->priv->registered = 1;
1172
1173 event_return = lttng_kernel_event_alloc(event_enabler);
1174 if (!event) {
1175 ret = -ENOMEM;
1176 goto alloc_error;
1177 }
1178
1179 event_return->enabled = 0;
1180 event_return->priv->registered = 1;
1181
1182 /*
1183 * Populate lttng_event structure before kretprobe registration.
1184 */
1185 smp_wmb();
1186 ret = lttng_kretprobes_register(event_name,
1187 event_param->u.kretprobe.symbol_name,
1188 event_param->u.kretprobe.offset,
1189 event_param->u.kretprobe.addr,
1190 event, event_return);
1191 if (ret) {
1192 lttng_kernel_event_free(event_return);
1193 ret = -EINVAL;
1194 goto register_error;
1195 }
1196 /* Take 2 refs on the module: one per event. */
1197 ret = try_module_get(event->priv->desc->owner);
1198 WARN_ON_ONCE(!ret);
1199 ret = try_module_get(event_return->priv->desc->owner);
1200 WARN_ON_ONCE(!ret);
1201 ret = _lttng_event_recorder_metadata_statedump(event_return);
1202 WARN_ON_ONCE(ret > 0);
1203 if (ret) {
1204 lttng_kernel_event_free(event_return);
1205 module_put(event_return->priv->desc->owner);
1206 module_put(event->priv->desc->owner);
1207 goto statedump_error;
1208 }
1209 list_add(&event_return->priv->node, event_list_head);
1210 break;
1211 }
1212
1213 case LTTNG_KERNEL_ABI_SYSCALL:
1214 /*
1215 * Needs to be explicitly enabled after creation, since
1216 * we may want to apply filters.
1217 */
1218 event->enabled = 0;
1219 event->priv->registered = 0;
1220 event->priv->desc = event_desc;
1221 switch (event_param->u.syscall.entryexit) {
1222 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
1223 ret = -EINVAL;
1224 goto register_error;
1225 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
1226 event->priv->u.syscall.entryexit = LTTNG_SYSCALL_ENTRY;
1227 break;
1228 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
1229 event->priv->u.syscall.entryexit = LTTNG_SYSCALL_EXIT;
1230 break;
1231 }
1232 switch (event_param->u.syscall.abi) {
1233 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
1234 ret = -EINVAL;
1235 goto register_error;
1236 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
1237 event->priv->u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE;
1238 break;
1239 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
1240 event->priv->u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT;
1241 break;
1242 }
1243 if (!event->priv->desc) {
1244 ret = -EINVAL;
1245 goto register_error;
1246 }
1247 break;
1248
1249 case LTTNG_KERNEL_ABI_UPROBE:
1250 /*
1251 * Needs to be explicitly enabled after creation, since
1252 * we may want to apply filters.
1253 */
1254 event->enabled = 0;
1255 event->priv->registered = 1;
1256
1257 /*
1258 * Populate lttng_event structure before event
1259 * registration.
1260 */
1261 smp_wmb();
1262
1263 ret = lttng_uprobes_register_event(event_param->name,
1264 event_param->u.uprobe.fd,
1265 event);
1266 if (ret)
1267 goto register_error;
1268 ret = try_module_get(event->priv->desc->owner);
1269 WARN_ON_ONCE(!ret);
1270 break;
1271
1272 default:
1273 WARN_ON_ONCE(1);
1274 ret = -EINVAL;
1275 goto register_error;
1276 }
1277
1278 ret = _lttng_event_recorder_metadata_statedump(event);
1279 WARN_ON_ONCE(ret > 0);
1280 if (ret) {
1281 goto statedump_error;
1282 }
1283
1284 ret = lttng_kernel_event_notifier_clear_error_counter(event);
1285 if (ret)
1286 goto register_error;
1287
1288 hlist_add_head(&event->priv->hlist_node, head);
1289 list_add(&event->priv->node, event_list_head);
1290
1291 return event;
1292
1293 statedump_error:
1294 /* If a statedump error occurs, events will not be readable. */
1295 register_error:
1296 lttng_kernel_event_free(event);
1297 alloc_error:
1298 exist:
1299 type_error:
1300 full:
1301 return ERR_PTR(ret);
1302 }
1303
1304 struct lttng_kernel_event_common *lttng_kernel_event_create(struct lttng_event_enabler_common *event_enabler,
1305 const struct lttng_kernel_event_desc *event_desc)
1306 {
1307 struct lttng_kernel_event_common *event;
1308
1309 mutex_lock(&sessions_mutex);
1310 event = _lttng_kernel_event_create(event_enabler, event_desc);
1311 mutex_unlock(&sessions_mutex);
1312 return event;
1313 }
1314
1315 int lttng_kernel_counter_read(struct lttng_counter *counter,
1316 const size_t *dim_indexes, int32_t cpu,
1317 int64_t *val, bool *overflow, bool *underflow)
1318 {
1319 return counter->ops->counter_read(counter->counter, dim_indexes,
1320 cpu, val, overflow, underflow);
1321 }
1322
1323 int lttng_kernel_counter_aggregate(struct lttng_counter *counter,
1324 const size_t *dim_indexes, int64_t *val,
1325 bool *overflow, bool *underflow)
1326 {
1327 return counter->ops->counter_aggregate(counter->counter, dim_indexes,
1328 val, overflow, underflow);
1329 }
1330
1331 int lttng_kernel_counter_clear(struct lttng_counter *counter,
1332 const size_t *dim_indexes)
1333 {
1334 return counter->ops->counter_clear(counter->counter, dim_indexes);
1335 }
1336
1337 /* Only used for tracepoints and system calls for now. */
1338 static
1339 void register_event(struct lttng_kernel_event_common *event)
1340 {
1341 const struct lttng_kernel_event_desc *desc;
1342 int ret = -EINVAL;
1343
1344 WARN_ON_ONCE(event->priv->registered);
1345
1346 desc = event->priv->desc;
1347 switch (event->priv->instrumentation) {
1348 case LTTNG_KERNEL_ABI_TRACEPOINT:
1349 ret = lttng_wrapper_tracepoint_probe_register(desc->event_kname,
1350 desc->tp_class->probe_callback,
1351 event);
1352 break;
1353
1354 case LTTNG_KERNEL_ABI_SYSCALL:
1355 ret = lttng_syscall_filter_enable_event(event);
1356 break;
1357
1358 case LTTNG_KERNEL_ABI_KPROBE:
1359 lttng_fallthrough;
1360 case LTTNG_KERNEL_ABI_UPROBE:
1361 ret = 0;
1362 break;
1363
1364 case LTTNG_KERNEL_ABI_KRETPROBE:
1365 switch (event->type) {
1366 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1367 ret = 0;
1368 break;
1369 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1370 WARN_ON_ONCE(1);
1371 break;
1372 }
1373 break;
1374
1375 case LTTNG_KERNEL_ABI_FUNCTION:
1376 lttng_fallthrough;
1377 case LTTNG_KERNEL_ABI_NOOP:
1378 lttng_fallthrough;
1379 default:
1380 WARN_ON_ONCE(1);
1381 }
1382 WARN_ON_ONCE(ret);
1383 if (!ret)
1384 event->priv->registered = 1;
1385 }
1386
1387 static
1388 void unregister_event(struct lttng_kernel_event_common *event)
1389 {
1390 struct lttng_kernel_event_common_private *event_priv = event->priv;
1391 const struct lttng_kernel_event_desc *desc;
1392 int ret = -EINVAL;
1393
1394 WARN_ON_ONCE(!event->priv->registered);
1395
1396 desc = event_priv->desc;
1397 switch (event_priv->instrumentation) {
1398 case LTTNG_KERNEL_ABI_TRACEPOINT:
1399 ret = lttng_wrapper_tracepoint_probe_unregister(event_priv->desc->event_kname,
1400 event_priv->desc->tp_class->probe_callback,
1401 event);
1402 break;
1403
1404 case LTTNG_KERNEL_ABI_KPROBE:
1405 lttng_kprobes_unregister_event(event);
1406 ret = 0;
1407 break;
1408
1409 case LTTNG_KERNEL_ABI_KRETPROBE:
1410 switch (event->type) {
1411 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1412 lttng_kretprobes_unregister(event);
1413 ret = 0;
1414 break;
1415 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1416 WARN_ON_ONCE(1);
1417 break;
1418 }
1419 break;
1420
1421 case LTTNG_KERNEL_ABI_SYSCALL:
1422 ret = lttng_syscall_filter_disable_event(event);
1423 break;
1424
1425 case LTTNG_KERNEL_ABI_NOOP:
1426 switch (event->type) {
1427 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1428 ret = 0;
1429 break;
1430 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1431 WARN_ON_ONCE(1);
1432 break;
1433 }
1434 break;
1435
1436 case LTTNG_KERNEL_ABI_UPROBE:
1437 lttng_uprobes_unregister_event(event);
1438 ret = 0;
1439 break;
1440
1441 case LTTNG_KERNEL_ABI_FUNCTION:
1442 lttng_fallthrough;
1443 default:
1444 WARN_ON_ONCE(1);
1445 }
1446 WARN_ON_ONCE(ret);
1447 if (!ret)
1448 event_priv->registered = 0;
1449 }
1450
1451 static
1452 void _lttng_event_unregister(struct lttng_kernel_event_common *event)
1453 {
1454 if (event->priv->registered)
1455 unregister_event(event);
1456 }
1457
1458 /*
1459 * Only used internally at session destruction.
1460 */
1461 static
1462 void _lttng_event_destroy(struct lttng_kernel_event_common *event)
1463 {
1464 struct lttng_kernel_event_common_private *event_priv = event->priv;
1465 struct lttng_enabler_ref *enabler_ref, *tmp_enabler_ref;
1466
1467 lttng_free_event_filter_runtime(event);
1468 /* Free event enabler refs */
1469 list_for_each_entry_safe(enabler_ref, tmp_enabler_ref,
1470 &event_priv->enablers_ref_head, node)
1471 kfree(enabler_ref);
1472
1473 switch (event->type) {
1474 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1475 {
1476 struct lttng_kernel_event_recorder *event_recorder =
1477 container_of(event, struct lttng_kernel_event_recorder, parent);
1478
1479 switch (event_priv->instrumentation) {
1480 case LTTNG_KERNEL_ABI_TRACEPOINT:
1481 lttng_event_desc_put(event_priv->desc);
1482 break;
1483
1484 case LTTNG_KERNEL_ABI_KPROBE:
1485 module_put(event_priv->desc->owner);
1486 lttng_kprobes_destroy_event_private(&event_recorder->parent);
1487 break;
1488
1489 case LTTNG_KERNEL_ABI_KRETPROBE:
1490 module_put(event_priv->desc->owner);
1491 lttng_kretprobes_destroy_private(&event_recorder->parent);
1492 break;
1493
1494 case LTTNG_KERNEL_ABI_SYSCALL:
1495 break;
1496
1497 case LTTNG_KERNEL_ABI_UPROBE:
1498 module_put(event_priv->desc->owner);
1499 lttng_uprobes_destroy_event_private(&event_recorder->parent);
1500 break;
1501
1502 case LTTNG_KERNEL_ABI_FUNCTION:
1503 lttng_fallthrough;
1504 case LTTNG_KERNEL_ABI_NOOP:
1505 lttng_fallthrough;
1506 default:
1507 WARN_ON_ONCE(1);
1508 }
1509 list_del(&event_recorder->priv->parent.node);
1510 kmem_cache_free(event_recorder_private_cache, event_recorder->priv);
1511 kmem_cache_free(event_recorder_cache, event_recorder);
1512 break;
1513 }
1514 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1515 {
1516 struct lttng_kernel_event_notifier *event_notifier =
1517 container_of(event, struct lttng_kernel_event_notifier, parent);
1518
1519 switch (event_notifier->priv->parent.instrumentation) {
1520 case LTTNG_KERNEL_ABI_TRACEPOINT:
1521 lttng_event_desc_put(event_notifier->priv->parent.desc);
1522 break;
1523
1524 case LTTNG_KERNEL_ABI_KPROBE:
1525 module_put(event_notifier->priv->parent.desc->owner);
1526 lttng_kprobes_destroy_event_private(&event_notifier->parent);
1527 break;
1528
1529 case LTTNG_KERNEL_ABI_SYSCALL:
1530 break;
1531
1532 case LTTNG_KERNEL_ABI_UPROBE:
1533 module_put(event_notifier->priv->parent.desc->owner);
1534 lttng_uprobes_destroy_event_private(&event_notifier->parent);
1535 break;
1536
1537 case LTTNG_KERNEL_ABI_KRETPROBE:
1538 lttng_fallthrough;
1539 case LTTNG_KERNEL_ABI_FUNCTION:
1540 lttng_fallthrough;
1541 case LTTNG_KERNEL_ABI_NOOP:
1542 lttng_fallthrough;
1543 default:
1544 WARN_ON_ONCE(1);
1545 }
1546 list_del(&event_notifier->priv->parent.node);
1547 kmem_cache_free(event_notifier_private_cache, event_notifier->priv);
1548 kmem_cache_free(event_notifier_cache, event_notifier);
1549 break;
1550 }
1551 default:
1552 WARN_ON_ONCE(1);
1553 }
1554 }
1555
1556 struct lttng_kernel_id_tracker *get_tracker(struct lttng_kernel_session *session,
1557 enum tracker_type tracker_type)
1558 {
1559 switch (tracker_type) {
1560 case TRACKER_PID:
1561 return &session->pid_tracker;
1562 case TRACKER_VPID:
1563 return &session->vpid_tracker;
1564 case TRACKER_UID:
1565 return &session->uid_tracker;
1566 case TRACKER_VUID:
1567 return &session->vuid_tracker;
1568 case TRACKER_GID:
1569 return &session->gid_tracker;
1570 case TRACKER_VGID:
1571 return &session->vgid_tracker;
1572 default:
1573 WARN_ON_ONCE(1);
1574 return NULL;
1575 }
1576 }
1577
1578 int lttng_session_track_id(struct lttng_kernel_session *session,
1579 enum tracker_type tracker_type, int id)
1580 {
1581 struct lttng_kernel_id_tracker *tracker;
1582 int ret;
1583
1584 tracker = get_tracker(session, tracker_type);
1585 if (!tracker)
1586 return -EINVAL;
1587 if (id < -1)
1588 return -EINVAL;
1589 mutex_lock(&sessions_mutex);
1590 if (id == -1) {
1591 /* track all ids: destroy tracker. */
1592 lttng_id_tracker_destroy(tracker, true);
1593 ret = 0;
1594 } else {
1595 ret = lttng_id_tracker_add(tracker, id);
1596 }
1597 mutex_unlock(&sessions_mutex);
1598 return ret;
1599 }
1600
1601 int lttng_session_untrack_id(struct lttng_kernel_session *session,
1602 enum tracker_type tracker_type, int id)
1603 {
1604 struct lttng_kernel_id_tracker *tracker;
1605 int ret;
1606
1607 tracker = get_tracker(session, tracker_type);
1608 if (!tracker)
1609 return -EINVAL;
1610 if (id < -1)
1611 return -EINVAL;
1612 mutex_lock(&sessions_mutex);
1613 if (id == -1) {
1614 /* untrack all ids: replace by empty tracker. */
1615 ret = lttng_id_tracker_empty_set(tracker);
1616 } else {
1617 ret = lttng_id_tracker_del(tracker, id);
1618 }
1619 mutex_unlock(&sessions_mutex);
1620 return ret;
1621 }
1622
1623 static
1624 void *id_list_start(struct seq_file *m, loff_t *pos)
1625 {
1626 struct lttng_kernel_id_tracker *id_tracker = m->private;
1627 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1628 struct lttng_id_hash_node *e;
1629 int iter = 0, i;
1630
1631 mutex_lock(&sessions_mutex);
1632 if (id_tracker_p) {
1633 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1634 struct hlist_head *head = &id_tracker_p->id_hash[i];
1635
1636 lttng_hlist_for_each_entry(e, head, hlist) {
1637 if (iter++ >= *pos)
1638 return e;
1639 }
1640 }
1641 } else {
1642 /* ID tracker disabled. */
1643 if (iter >= *pos && iter == 0) {
1644 return id_tracker_p; /* empty tracker */
1645 }
1646 iter++;
1647 }
1648 /* End of list */
1649 return NULL;
1650 }
1651
1652 /* Called with sessions_mutex held. */
1653 static
1654 void *id_list_next(struct seq_file *m, void *p, loff_t *ppos)
1655 {
1656 struct lttng_kernel_id_tracker *id_tracker = m->private;
1657 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1658 struct lttng_id_hash_node *e;
1659 int iter = 0, i;
1660
1661 (*ppos)++;
1662 if (id_tracker_p) {
1663 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1664 struct hlist_head *head = &id_tracker_p->id_hash[i];
1665
1666 lttng_hlist_for_each_entry(e, head, hlist) {
1667 if (iter++ >= *ppos)
1668 return e;
1669 }
1670 }
1671 } else {
1672 /* ID tracker disabled. */
1673 if (iter >= *ppos && iter == 0)
1674 return p; /* empty tracker */
1675 iter++;
1676 }
1677
1678 /* End of list */
1679 return NULL;
1680 }
1681
1682 static
1683 void id_list_stop(struct seq_file *m, void *p)
1684 {
1685 mutex_unlock(&sessions_mutex);
1686 }
1687
1688 static
1689 int id_list_show(struct seq_file *m, void *p)
1690 {
1691 struct lttng_kernel_id_tracker *id_tracker = m->private;
1692 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1693 int id;
1694
1695 if (p == id_tracker_p) {
1696 /* Tracker disabled. */
1697 id = -1;
1698 } else {
1699 const struct lttng_id_hash_node *e = p;
1700
1701 id = lttng_id_tracker_get_node_id(e);
1702 }
1703 switch (id_tracker->priv->tracker_type) {
1704 case TRACKER_PID:
1705 seq_printf(m, "process { pid = %d; };\n", id);
1706 break;
1707 case TRACKER_VPID:
1708 seq_printf(m, "process { vpid = %d; };\n", id);
1709 break;
1710 case TRACKER_UID:
1711 seq_printf(m, "user { uid = %d; };\n", id);
1712 break;
1713 case TRACKER_VUID:
1714 seq_printf(m, "user { vuid = %d; };\n", id);
1715 break;
1716 case TRACKER_GID:
1717 seq_printf(m, "group { gid = %d; };\n", id);
1718 break;
1719 case TRACKER_VGID:
1720 seq_printf(m, "group { vgid = %d; };\n", id);
1721 break;
1722 default:
1723 seq_printf(m, "UNKNOWN { field = %d };\n", id);
1724 }
1725 return 0;
1726 }
1727
1728 static
1729 const struct seq_operations lttng_tracker_ids_list_seq_ops = {
1730 .start = id_list_start,
1731 .next = id_list_next,
1732 .stop = id_list_stop,
1733 .show = id_list_show,
1734 };
1735
1736 static
1737 int lttng_tracker_ids_list_open(struct inode *inode, struct file *file)
1738 {
1739 return seq_open(file, &lttng_tracker_ids_list_seq_ops);
1740 }
1741
1742 static
1743 int lttng_tracker_ids_list_release(struct inode *inode, struct file *file)
1744 {
1745 struct seq_file *m = file->private_data;
1746 struct lttng_kernel_id_tracker *id_tracker = m->private;
1747 int ret;
1748
1749 WARN_ON_ONCE(!id_tracker);
1750 ret = seq_release(inode, file);
1751 if (!ret)
1752 fput(id_tracker->priv->session->priv->file);
1753 return ret;
1754 }
1755
1756 const struct file_operations lttng_tracker_ids_list_fops = {
1757 .owner = THIS_MODULE,
1758 .open = lttng_tracker_ids_list_open,
1759 .read = seq_read,
1760 .llseek = seq_lseek,
1761 .release = lttng_tracker_ids_list_release,
1762 };
1763
1764 int lttng_session_list_tracker_ids(struct lttng_kernel_session *session,
1765 enum tracker_type tracker_type)
1766 {
1767 struct file *tracker_ids_list_file;
1768 struct seq_file *m;
1769 int file_fd, ret;
1770
1771 file_fd = get_unused_fd_flags(0);
1772 if (file_fd < 0) {
1773 ret = file_fd;
1774 goto fd_error;
1775 }
1776
1777 tracker_ids_list_file = anon_inode_getfile("[lttng_tracker_ids_list]",
1778 &lttng_tracker_ids_list_fops,
1779 NULL, O_RDWR);
1780 if (IS_ERR(tracker_ids_list_file)) {
1781 ret = PTR_ERR(tracker_ids_list_file);
1782 goto file_error;
1783 }
1784 if (!atomic_long_add_unless(&session->priv->file->f_count, 1, LONG_MAX)) {
1785 ret = -EOVERFLOW;
1786 goto refcount_error;
1787 }
1788 ret = lttng_tracker_ids_list_fops.open(NULL, tracker_ids_list_file);
1789 if (ret < 0)
1790 goto open_error;
1791 m = tracker_ids_list_file->private_data;
1792
1793 m->private = get_tracker(session, tracker_type);
1794 BUG_ON(!m->private);
1795 fd_install(file_fd, tracker_ids_list_file);
1796
1797 return file_fd;
1798
1799 open_error:
1800 atomic_long_dec(&session->priv->file->f_count);
1801 refcount_error:
1802 fput(tracker_ids_list_file);
1803 file_error:
1804 put_unused_fd(file_fd);
1805 fd_error:
1806 return ret;
1807 }
1808
1809 /*
1810 * Enabler management.
1811 */
1812 static
1813 int lttng_match_enabler_star_glob(const char *desc_name,
1814 const char *pattern)
1815 {
1816 if (!strutils_star_glob_match(pattern, LTTNG_SIZE_MAX,
1817 desc_name, LTTNG_SIZE_MAX))
1818 return 0;
1819 return 1;
1820 }
1821
1822 static
1823 int lttng_match_enabler_name(const char *desc_name,
1824 const char *name)
1825 {
1826 if (strcmp(desc_name, name))
1827 return 0;
1828 return 1;
1829 }
1830
1831 static
1832 int lttng_desc_match_enabler_check(const struct lttng_kernel_event_desc *desc,
1833 struct lttng_event_enabler_common *enabler)
1834 {
1835 const char *desc_name, *enabler_name;
1836 bool compat = false, entry = false;
1837
1838 enabler_name = enabler->event_param.name;
1839 switch (enabler->event_param.instrumentation) {
1840 case LTTNG_KERNEL_ABI_TRACEPOINT:
1841 desc_name = desc->event_name;
1842 switch (enabler->format_type) {
1843 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
1844 return lttng_match_enabler_star_glob(desc_name, enabler_name);
1845 case LTTNG_ENABLER_FORMAT_NAME:
1846 return lttng_match_enabler_name(desc_name, enabler_name);
1847 default:
1848 return -EINVAL;
1849 }
1850 break;
1851
1852 case LTTNG_KERNEL_ABI_SYSCALL:
1853 desc_name = desc->event_name;
1854 if (!strncmp(desc_name, "compat_", strlen("compat_"))) {
1855 desc_name += strlen("compat_");
1856 compat = true;
1857 }
1858 if (!strncmp(desc_name, "syscall_exit_",
1859 strlen("syscall_exit_"))) {
1860 desc_name += strlen("syscall_exit_");
1861 } else if (!strncmp(desc_name, "syscall_entry_",
1862 strlen("syscall_entry_"))) {
1863 desc_name += strlen("syscall_entry_");
1864 entry = true;
1865 } else {
1866 WARN_ON_ONCE(1);
1867 return -EINVAL;
1868 }
1869 switch (enabler->event_param.u.syscall.entryexit) {
1870 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
1871 break;
1872 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
1873 if (!entry)
1874 return 0;
1875 break;
1876 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
1877 if (entry)
1878 return 0;
1879 break;
1880 default:
1881 return -EINVAL;
1882 }
1883 switch (enabler->event_param.u.syscall.abi) {
1884 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
1885 break;
1886 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
1887 if (compat)
1888 return 0;
1889 break;
1890 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
1891 if (!compat)
1892 return 0;
1893 break;
1894 default:
1895 return -EINVAL;
1896 }
1897 switch (enabler->event_param.u.syscall.match) {
1898 case LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME:
1899 switch (enabler->format_type) {
1900 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
1901 return lttng_match_enabler_star_glob(desc_name, enabler_name);
1902 case LTTNG_ENABLER_FORMAT_NAME:
1903 return lttng_match_enabler_name(desc_name, enabler_name);
1904 default:
1905 return -EINVAL;
1906 }
1907 break;
1908 case LTTNG_KERNEL_ABI_SYSCALL_MATCH_NR:
1909 return -EINVAL; /* Not implemented. */
1910 default:
1911 return -EINVAL;
1912 }
1913 break;
1914
1915 default:
1916 WARN_ON_ONCE(1);
1917 return -EINVAL;
1918 }
1919 }
1920
1921 bool lttng_desc_match_enabler(const struct lttng_kernel_event_desc *desc,
1922 struct lttng_event_enabler_common *enabler)
1923 {
1924 int ret;
1925
1926 ret = lttng_desc_match_enabler_check(desc, enabler);
1927 if (ret < 0) {
1928 WARN_ON_ONCE(1);
1929 return false;
1930 }
1931 return ret;
1932 }
1933
1934 bool lttng_event_enabler_match_event(struct lttng_event_enabler_common *event_enabler,
1935 struct lttng_kernel_event_common *event)
1936 {
1937 if (event_enabler->event_param.instrumentation != event->priv->instrumentation)
1938 return false;
1939
1940 switch (event_enabler->enabler_type) {
1941 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
1942 {
1943 struct lttng_event_recorder_enabler *event_recorder_enabler =
1944 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
1945 struct lttng_kernel_event_recorder *event_recorder =
1946 container_of(event, struct lttng_kernel_event_recorder, parent);
1947
1948 if (lttng_desc_match_enabler(event->priv->desc, event_enabler)
1949 && event_recorder->chan == event_recorder_enabler->chan)
1950 return true;
1951 else
1952 return false;
1953 }
1954 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
1955 {
1956 struct lttng_event_notifier_enabler *event_notifier_enabler =
1957 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
1958 struct lttng_kernel_event_notifier *event_notifier =
1959 container_of(event, struct lttng_kernel_event_notifier, parent);
1960
1961 if (lttng_desc_match_enabler(event->priv->desc, event_enabler)
1962 && event_notifier->priv->group == event_notifier_enabler->group
1963 && event->priv->user_token == event_enabler->user_token)
1964 return true;
1965 else
1966 return false;
1967 }
1968 default:
1969 WARN_ON_ONCE(1);
1970 return false;
1971 }
1972 }
1973
1974 bool lttng_event_enabler_desc_match_event(struct lttng_event_enabler_common *event_enabler,
1975 const struct lttng_kernel_event_desc *desc,
1976 struct lttng_kernel_event_common *event)
1977 {
1978 if (event_enabler->event_param.instrumentation != event->priv->instrumentation)
1979 return false;
1980
1981 switch (event_enabler->enabler_type) {
1982 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
1983 {
1984 struct lttng_event_recorder_enabler *event_recorder_enabler =
1985 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
1986 struct lttng_kernel_event_recorder *event_recorder =
1987 container_of(event, struct lttng_kernel_event_recorder, parent);
1988
1989 if (event->priv->desc == desc && event_recorder->chan == event_recorder_enabler->chan)
1990 return true;
1991 else
1992 return false;
1993 }
1994 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
1995 {
1996 struct lttng_event_notifier_enabler *event_notifier_enabler =
1997 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
1998 struct lttng_kernel_event_notifier *event_notifier =
1999 container_of(event, struct lttng_kernel_event_notifier, parent);
2000
2001 if (event->priv->desc == desc
2002 && event_notifier->priv->group == event_notifier_enabler->group
2003 && event->priv->user_token == event_enabler->user_token)
2004 return true;
2005 else
2006 return false;
2007 }
2008 default:
2009 WARN_ON_ONCE(1);
2010 return false;
2011 }
2012 }
2013
2014 bool lttng_event_enabler_event_name_match_event(struct lttng_event_enabler_common *event_enabler,
2015 const char *event_name,
2016 struct lttng_kernel_event_common *event)
2017 {
2018 if (event_enabler->event_param.instrumentation != event->priv->instrumentation)
2019 return false;
2020
2021 switch (event_enabler->enabler_type) {
2022 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
2023 {
2024 struct lttng_event_recorder_enabler *event_recorder_enabler =
2025 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
2026 struct lttng_kernel_event_recorder *event_recorder =
2027 container_of(event, struct lttng_kernel_event_recorder, parent);
2028
2029 if (!strncmp(event->priv->desc->event_name, event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1)
2030 && event_recorder->chan == event_recorder_enabler->chan)
2031 return true;
2032 else
2033 return false;
2034 }
2035 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
2036 {
2037 struct lttng_event_notifier_enabler *event_notifier_enabler =
2038 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
2039 struct lttng_kernel_event_notifier *event_notifier =
2040 container_of(event, struct lttng_kernel_event_notifier, parent);
2041
2042 if (!strncmp(event->priv->desc->event_name, event_name, LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1)
2043 && event_notifier->priv->group == event_notifier_enabler->group
2044 && event->priv->user_token == event_enabler->user_token)
2045 return true;
2046 else
2047 return false;
2048 }
2049 default:
2050 WARN_ON_ONCE(1);
2051 return false;
2052 }
2053 }
2054
2055 static
2056 struct lttng_enabler_ref *lttng_enabler_ref(
2057 struct list_head *enablers_ref_list,
2058 struct lttng_event_enabler_common *enabler)
2059 {
2060 struct lttng_enabler_ref *enabler_ref;
2061
2062 list_for_each_entry(enabler_ref, enablers_ref_list, node) {
2063 if (enabler_ref->ref == enabler)
2064 return enabler_ref;
2065 }
2066 return NULL;
2067 }
2068
2069 static
2070 void lttng_event_enabler_create_tracepoint_events_if_missing(struct lttng_event_enabler_common *event_enabler)
2071 {
2072 struct lttng_event_ht *events_ht = lttng_get_event_ht_from_enabler(event_enabler);
2073 struct lttng_kernel_probe_desc *probe_desc;
2074 const struct lttng_kernel_event_desc *desc;
2075 struct list_head *probe_list;
2076 int i;
2077
2078 probe_list = lttng_get_probe_list_head();
2079 /*
2080 * For each probe event, if we find that a probe event matches
2081 * our enabler, create an associated lttng_event if not
2082 * already present.
2083 */
2084 list_for_each_entry(probe_desc, probe_list, head) {
2085 for (i = 0; i < probe_desc->nr_events; i++) {
2086 bool found = false;
2087 struct hlist_head *head;
2088 struct lttng_kernel_event_common *event;
2089 struct lttng_kernel_event_common_private *event_priv;
2090
2091 desc = probe_desc->event_desc[i];
2092 if (!lttng_desc_match_enabler(desc, event_enabler))
2093 continue;
2094
2095 /*
2096 * Check if already created.
2097 */
2098 head = utils_borrow_hash_table_bucket(events_ht->table, LTTNG_EVENT_HT_SIZE, desc->event_name);
2099 lttng_hlist_for_each_entry(event_priv, head, hlist_node) {
2100 if (lttng_event_enabler_desc_match_event(event_enabler, desc, event_priv->pub)) {
2101 found = true;
2102 break;
2103 }
2104 }
2105 if (found)
2106 continue;
2107
2108 /*
2109 * We need to create an event for this event probe.
2110 */
2111 event = _lttng_kernel_event_create(event_enabler, desc);
2112 if (IS_ERR(event)) {
2113 printk(KERN_INFO "LTTng: Unable to create event %s\n",
2114 probe_desc->event_desc[i]->event_name);
2115 }
2116 }
2117 }
2118 }
2119
2120 /*
2121 * Create event if it is missing and present in the list of tracepoint probes.
2122 * Should be called with sessions mutex held.
2123 */
2124 static
2125 void lttng_event_enabler_create_events_if_missing(struct lttng_event_enabler_common *event_enabler)
2126 {
2127 int ret;
2128
2129 switch (event_enabler->event_param.instrumentation) {
2130 case LTTNG_KERNEL_ABI_TRACEPOINT:
2131 lttng_event_enabler_create_tracepoint_events_if_missing(event_enabler);
2132 break;
2133
2134 case LTTNG_KERNEL_ABI_SYSCALL:
2135 ret = lttng_event_enabler_create_syscall_events_if_missing(event_enabler);
2136 WARN_ON_ONCE(ret);
2137 break;
2138
2139 default:
2140 WARN_ON_ONCE(1);
2141 break;
2142 }
2143 }
2144
2145 static
2146 void lttng_event_enabler_init_event_filter(struct lttng_event_enabler_common *event_enabler,
2147 struct lttng_kernel_event_common *event)
2148 {
2149 /* Link filter bytecodes if not linked yet. */
2150 lttng_enabler_link_bytecode(event->priv->desc, lttng_static_ctx,
2151 &event->priv->filter_bytecode_runtime_head, &event_enabler->filter_bytecode_head);
2152 }
2153
2154 static
2155 void lttng_event_enabler_init_event_capture(struct lttng_event_enabler_common *event_enabler,
2156 struct lttng_kernel_event_common *event)
2157 {
2158 switch (event_enabler->enabler_type) {
2159 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
2160 break;
2161 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
2162 {
2163 struct lttng_event_notifier_enabler *event_notifier_enabler =
2164 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
2165 struct lttng_kernel_event_notifier *event_notifier =
2166 container_of(event, struct lttng_kernel_event_notifier, parent);
2167
2168 /* Link capture bytecodes if not linked yet. */
2169 lttng_enabler_link_bytecode(event->priv->desc,
2170 lttng_static_ctx, &event_notifier->priv->capture_bytecode_runtime_head,
2171 &event_notifier_enabler->capture_bytecode_head);
2172 event_notifier->priv->num_captures = event_notifier_enabler->num_captures;
2173 break;
2174 }
2175 default:
2176 WARN_ON_ONCE(1);
2177 }
2178 }
2179
2180 /*
2181 * Create events associated with an event_enabler (if not already present),
2182 * and add backward reference from the event to the enabler.
2183 * Should be called with sessions mutex held.
2184 */
2185 static
2186 int lttng_event_enabler_ref_events(struct lttng_event_enabler_common *event_enabler)
2187 {
2188 struct list_head *event_list_head = lttng_get_event_list_head_from_enabler(event_enabler);
2189 struct lttng_kernel_event_common_private *event_priv;
2190
2191 lttng_syscall_table_set_wildcard_all(event_enabler);
2192
2193 /* First ensure that probe events are created for this enabler. */
2194 lttng_event_enabler_create_events_if_missing(event_enabler);
2195
2196 /* Link the created event with its associated enabler. */
2197 list_for_each_entry(event_priv, event_list_head, node) {
2198 struct lttng_kernel_event_common *event = event_priv->pub;
2199 struct lttng_enabler_ref *enabler_ref;
2200
2201 if (!lttng_event_enabler_match_event(event_enabler, event))
2202 continue;
2203
2204 enabler_ref = lttng_enabler_ref(&event_priv->enablers_ref_head, event_enabler);
2205 if (!enabler_ref) {
2206 /*
2207 * If no backward ref, create it.
2208 * Add backward ref from event_notifier to enabler.
2209 */
2210 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
2211 if (!enabler_ref)
2212 return -ENOMEM;
2213
2214 enabler_ref->ref = event_enabler;
2215 list_add(&enabler_ref->node, &event_priv->enablers_ref_head);
2216 }
2217
2218 lttng_event_enabler_init_event_filter(event_enabler, event);
2219 lttng_event_enabler_init_event_capture(event_enabler, event);
2220 }
2221 return 0;
2222 }
2223
2224 /*
2225 * Called at module load: connect the probe on all enablers matching
2226 * this event.
2227 * Called with sessions lock held.
2228 */
2229 int lttng_fix_pending_events(void)
2230 {
2231 struct lttng_kernel_session_private *session_priv;
2232
2233 list_for_each_entry(session_priv, &sessions, list)
2234 lttng_session_lazy_sync_event_enablers(session_priv->pub);
2235 return 0;
2236 }
2237
2238 static bool lttng_event_notifier_group_has_active_event_notifiers(
2239 struct lttng_event_notifier_group *event_notifier_group)
2240 {
2241 struct lttng_event_enabler_common *event_enabler;
2242
2243 list_for_each_entry(event_enabler, &event_notifier_group->enablers_head, node) {
2244 if (event_enabler->enabled)
2245 return true;
2246 }
2247 return false;
2248 }
2249
2250 bool lttng_event_notifier_active(void)
2251 {
2252 struct lttng_event_notifier_group *event_notifier_group;
2253
2254 list_for_each_entry(event_notifier_group, &event_notifier_groups, node) {
2255 if (lttng_event_notifier_group_has_active_event_notifiers(event_notifier_group))
2256 return true;
2257 }
2258 return false;
2259 }
2260
2261 int lttng_fix_pending_event_notifiers(void)
2262 {
2263 struct lttng_event_notifier_group *event_notifier_group;
2264
2265 list_for_each_entry(event_notifier_group, &event_notifier_groups, node)
2266 lttng_event_notifier_group_sync_enablers(event_notifier_group);
2267 return 0;
2268 }
2269
2270 struct lttng_event_recorder_enabler *lttng_event_recorder_enabler_create(
2271 enum lttng_enabler_format_type format_type,
2272 struct lttng_kernel_abi_event *event_param,
2273 struct lttng_kernel_channel_buffer *chan)
2274 {
2275 struct lttng_event_recorder_enabler *event_enabler;
2276
2277 event_enabler = kzalloc(sizeof(*event_enabler), GFP_KERNEL);
2278 if (!event_enabler)
2279 return NULL;
2280 event_enabler->parent.enabler_type = LTTNG_EVENT_ENABLER_TYPE_RECORDER;
2281 event_enabler->parent.format_type = format_type;
2282 INIT_LIST_HEAD(&event_enabler->parent.filter_bytecode_head);
2283 memcpy(&event_enabler->parent.event_param, event_param,
2284 sizeof(event_enabler->parent.event_param));
2285 event_enabler->chan = chan;
2286 /* ctx left NULL */
2287 event_enabler->parent.enabled = 0;
2288 return event_enabler;
2289 }
2290
2291 void lttng_event_enabler_session_add(struct lttng_kernel_session *session,
2292 struct lttng_event_recorder_enabler *event_enabler)
2293 {
2294 mutex_lock(&sessions_mutex);
2295 list_add(&event_enabler->parent.node, &session->priv->enablers_head);
2296 event_enabler->parent.published = true;
2297 lttng_session_lazy_sync_event_enablers(session);
2298 mutex_unlock(&sessions_mutex);
2299 }
2300
2301 int lttng_event_enabler_enable(struct lttng_event_enabler_common *event_enabler)
2302 {
2303 mutex_lock(&sessions_mutex);
2304 event_enabler->enabled = 1;
2305 lttng_event_enabler_sync(event_enabler);
2306 mutex_unlock(&sessions_mutex);
2307 return 0;
2308 }
2309
2310 int lttng_event_enabler_disable(struct lttng_event_enabler_common *event_enabler)
2311 {
2312 mutex_lock(&sessions_mutex);
2313 event_enabler->enabled = 0;
2314 lttng_event_enabler_sync(event_enabler);
2315 mutex_unlock(&sessions_mutex);
2316 return 0;
2317 }
2318
2319 static
2320 int lttng_enabler_attach_filter_bytecode(struct lttng_event_enabler_common *enabler,
2321 struct lttng_kernel_abi_filter_bytecode __user *bytecode)
2322 {
2323 struct lttng_kernel_bytecode_node *bytecode_node;
2324 uint32_t bytecode_len;
2325 int ret;
2326
2327 ret = get_user(bytecode_len, &bytecode->len);
2328 if (ret)
2329 return ret;
2330 bytecode_node = lttng_kvzalloc(sizeof(*bytecode_node) + bytecode_len,
2331 GFP_KERNEL);
2332 if (!bytecode_node)
2333 return -ENOMEM;
2334 ret = copy_from_user(&bytecode_node->bc, bytecode,
2335 sizeof(*bytecode) + bytecode_len);
2336 if (ret)
2337 goto error_free;
2338
2339 bytecode_node->type = LTTNG_KERNEL_BYTECODE_TYPE_FILTER;
2340 bytecode_node->enabler = enabler;
2341 /* Enforce length based on allocated size */
2342 bytecode_node->bc.len = bytecode_len;
2343 list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head);
2344
2345 return 0;
2346
2347 error_free:
2348 lttng_kvfree(bytecode_node);
2349 return ret;
2350 }
2351
2352 int lttng_event_enabler_attach_filter_bytecode(struct lttng_event_enabler_common *event_enabler,
2353 struct lttng_kernel_abi_filter_bytecode __user *bytecode)
2354 {
2355 int ret;
2356 ret = lttng_enabler_attach_filter_bytecode(event_enabler, bytecode);
2357 if (ret)
2358 goto error;
2359 lttng_event_enabler_sync(event_enabler);
2360 return 0;
2361
2362 error:
2363 return ret;
2364 }
2365
2366 int lttng_event_add_callsite(struct lttng_kernel_event_common *event,
2367 struct lttng_kernel_abi_event_callsite __user *callsite)
2368 {
2369
2370 switch (event->priv->instrumentation) {
2371 case LTTNG_KERNEL_ABI_UPROBE:
2372 return lttng_uprobes_event_add_callsite(event, callsite);
2373 default:
2374 return -EINVAL;
2375 }
2376 }
2377
2378 static
2379 void lttng_enabler_destroy(struct lttng_event_enabler_common *enabler)
2380 {
2381 struct lttng_kernel_bytecode_node *filter_node, *tmp_filter_node;
2382
2383 /* Destroy filter bytecode */
2384 list_for_each_entry_safe(filter_node, tmp_filter_node,
2385 &enabler->filter_bytecode_head, node) {
2386 lttng_kvfree(filter_node);
2387 }
2388 }
2389
2390 void lttng_event_enabler_destroy(struct lttng_event_enabler_common *event_enabler)
2391 {
2392 lttng_enabler_destroy(event_enabler);
2393 if (event_enabler->published)
2394 list_del(&event_enabler->node);
2395
2396 switch (event_enabler->enabler_type) {
2397 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
2398 {
2399 struct lttng_event_recorder_enabler *event_recorder_enabler =
2400 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
2401
2402 kfree(event_recorder_enabler);
2403 break;
2404 }
2405 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
2406 {
2407 struct lttng_event_notifier_enabler *event_notifier_enabler =
2408 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
2409
2410 kfree(event_notifier_enabler);
2411 break;
2412 }
2413 default:
2414 WARN_ON_ONCE(1);
2415 }
2416 }
2417
2418 struct lttng_event_notifier_enabler *lttng_event_notifier_enabler_create(
2419 enum lttng_enabler_format_type format_type,
2420 struct lttng_kernel_abi_event_notifier *event_notifier_param,
2421 struct lttng_event_notifier_group *event_notifier_group)
2422 {
2423 struct lttng_event_notifier_enabler *event_notifier_enabler;
2424
2425 event_notifier_enabler = kzalloc(sizeof(*event_notifier_enabler), GFP_KERNEL);
2426 if (!event_notifier_enabler)
2427 return NULL;
2428
2429 event_notifier_enabler->parent.enabler_type = LTTNG_EVENT_ENABLER_TYPE_NOTIFIER;
2430 event_notifier_enabler->parent.format_type = format_type;
2431 INIT_LIST_HEAD(&event_notifier_enabler->parent.filter_bytecode_head);
2432 INIT_LIST_HEAD(&event_notifier_enabler->capture_bytecode_head);
2433
2434 event_notifier_enabler->error_counter_index = event_notifier_param->error_counter_index;
2435 event_notifier_enabler->num_captures = 0;
2436
2437 memcpy(&event_notifier_enabler->parent.event_param, &event_notifier_param->event,
2438 sizeof(event_notifier_enabler->parent.event_param));
2439
2440 event_notifier_enabler->parent.enabled = 0;
2441 event_notifier_enabler->parent.user_token = event_notifier_param->event.token;
2442 event_notifier_enabler->group = event_notifier_group;
2443 return event_notifier_enabler;
2444 }
2445
2446 void lttng_event_notifier_enabler_group_add(struct lttng_event_notifier_group *event_notifier_group,
2447 struct lttng_event_notifier_enabler *event_notifier_enabler)
2448 {
2449 mutex_lock(&sessions_mutex);
2450 list_add(&event_notifier_enabler->parent.node, &event_notifier_enabler->group->enablers_head);
2451 event_notifier_enabler->parent.published = true;
2452 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2453 mutex_unlock(&sessions_mutex);
2454 }
2455
2456 int lttng_event_notifier_enabler_enable(
2457 struct lttng_event_notifier_enabler *event_notifier_enabler)
2458 {
2459 mutex_lock(&sessions_mutex);
2460 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->enabled = 1;
2461 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2462 mutex_unlock(&sessions_mutex);
2463 return 0;
2464 }
2465
2466 int lttng_event_notifier_enabler_disable(
2467 struct lttng_event_notifier_enabler *event_notifier_enabler)
2468 {
2469 mutex_lock(&sessions_mutex);
2470 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->enabled = 0;
2471 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2472 mutex_unlock(&sessions_mutex);
2473 return 0;
2474 }
2475
2476 int lttng_event_notifier_enabler_attach_capture_bytecode(
2477 struct lttng_event_notifier_enabler *event_notifier_enabler,
2478 struct lttng_kernel_abi_capture_bytecode __user *bytecode)
2479 {
2480 struct lttng_kernel_bytecode_node *bytecode_node;
2481 struct lttng_event_enabler_common *enabler =
2482 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler);
2483 uint32_t bytecode_len;
2484 int ret;
2485
2486 ret = get_user(bytecode_len, &bytecode->len);
2487 if (ret)
2488 return ret;
2489
2490 bytecode_node = lttng_kvzalloc(sizeof(*bytecode_node) + bytecode_len,
2491 GFP_KERNEL);
2492 if (!bytecode_node)
2493 return -ENOMEM;
2494
2495 ret = copy_from_user(&bytecode_node->bc, bytecode,
2496 sizeof(*bytecode) + bytecode_len);
2497 if (ret)
2498 goto error_free;
2499
2500 bytecode_node->type = LTTNG_KERNEL_BYTECODE_TYPE_CAPTURE;
2501 bytecode_node->enabler = enabler;
2502
2503 /* Enforce length based on allocated size */
2504 bytecode_node->bc.len = bytecode_len;
2505 list_add_tail(&bytecode_node->node, &event_notifier_enabler->capture_bytecode_head);
2506
2507 event_notifier_enabler->num_captures++;
2508
2509 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2510 goto end;
2511
2512 error_free:
2513 lttng_kvfree(bytecode_node);
2514 end:
2515 return ret;
2516 }
2517
2518 static
2519 void lttng_event_sync_filter_state(struct lttng_kernel_event_common *event)
2520 {
2521 int has_enablers_without_filter_bytecode = 0, nr_filters = 0;
2522 struct lttng_kernel_bytecode_runtime *runtime;
2523 struct lttng_enabler_ref *enabler_ref;
2524
2525 /* Check if has enablers without bytecode enabled */
2526 list_for_each_entry(enabler_ref, &event->priv->enablers_ref_head, node) {
2527 if (enabler_ref->ref->enabled
2528 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
2529 has_enablers_without_filter_bytecode = 1;
2530 break;
2531 }
2532 }
2533 event->priv->has_enablers_without_filter_bytecode = has_enablers_without_filter_bytecode;
2534
2535 /* Enable filters */
2536 list_for_each_entry(runtime, &event->priv->filter_bytecode_runtime_head, node) {
2537 lttng_bytecode_sync_state(runtime);
2538 nr_filters++;
2539 }
2540 WRITE_ONCE(event->eval_filter, !(has_enablers_without_filter_bytecode || !nr_filters));
2541 }
2542
2543 static
2544 void lttng_event_sync_capture_state(struct lttng_kernel_event_common *event)
2545 {
2546 switch (event->type) {
2547 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
2548 break;
2549 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
2550 {
2551 struct lttng_kernel_event_notifier *event_notifier =
2552 container_of(event, struct lttng_kernel_event_notifier, parent);
2553 struct lttng_kernel_bytecode_runtime *runtime;
2554 int nr_captures = 0;
2555
2556 /* Enable captures */
2557 list_for_each_entry(runtime, &event_notifier->priv->capture_bytecode_runtime_head, node) {
2558 lttng_bytecode_sync_state(runtime);
2559 nr_captures++;
2560 }
2561 WRITE_ONCE(event_notifier->eval_capture, !!nr_captures);
2562 break;
2563 }
2564 default:
2565 WARN_ON_ONCE(1);
2566 }
2567 }
2568
2569 static
2570 bool lttng_get_event_enabled_state(struct lttng_kernel_event_common *event)
2571 {
2572 struct lttng_enabler_ref *enabler_ref;
2573 bool enabled = false;
2574
2575 switch (event->priv->instrumentation) {
2576 case LTTNG_KERNEL_ABI_TRACEPOINT:
2577 lttng_fallthrough;
2578 case LTTNG_KERNEL_ABI_SYSCALL:
2579 /* Enable events */
2580 list_for_each_entry(enabler_ref, &event->priv->enablers_ref_head, node) {
2581 if (enabler_ref->ref->enabled) {
2582 enabled = true;
2583 break;
2584 }
2585 }
2586 break;
2587 default:
2588 WARN_ON_ONCE(1);
2589 return false;
2590 }
2591
2592 switch (event->type) {
2593 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
2594 {
2595 struct lttng_kernel_event_recorder *event_recorder =
2596 container_of(event, struct lttng_kernel_event_recorder, parent);
2597
2598 /*
2599 * Enabled state is based on union of enablers, with
2600 * intersection of session and channel transient enable
2601 * states.
2602 */
2603 return enabled && event_recorder->chan->parent.session->priv->tstate && event_recorder->chan->priv->parent.tstate;
2604 }
2605 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
2606 return enabled;
2607 default:
2608 WARN_ON_ONCE(1);
2609 return false;
2610 }
2611 }
2612
2613 static
2614 bool lttng_event_is_lazy_sync(struct lttng_kernel_event_common *event)
2615 {
2616 switch (event->priv->instrumentation) {
2617 case LTTNG_KERNEL_ABI_TRACEPOINT:
2618 lttng_fallthrough;
2619 case LTTNG_KERNEL_ABI_SYSCALL:
2620 return true;
2621
2622 default:
2623 /* Not handled with lazy sync. */
2624 return false;
2625 }
2626 }
2627
2628 /*
2629 * Should be called with sessions mutex held.
2630 */
2631 static
2632 void lttng_sync_event_list(struct list_head *event_enabler_list,
2633 struct list_head *event_list)
2634 {
2635 struct lttng_kernel_event_common_private *event_priv;
2636 struct lttng_event_enabler_common *event_enabler;
2637
2638 list_for_each_entry(event_enabler, event_enabler_list, node)
2639 lttng_event_enabler_ref_events(event_enabler);
2640
2641 /*
2642 * For each event, if at least one of its enablers is enabled,
2643 * and its channel and session transient states are enabled, we
2644 * enable the event, else we disable it.
2645 */
2646 list_for_each_entry(event_priv, event_list, node) {
2647 struct lttng_kernel_event_common *event = event_priv->pub;
2648 bool enabled;
2649
2650 if (!lttng_event_is_lazy_sync(event))
2651 continue;
2652
2653 enabled = lttng_get_event_enabled_state(event);
2654 WRITE_ONCE(event->enabled, enabled);
2655 /*
2656 * Sync tracepoint registration with event enabled state.
2657 */
2658 if (enabled) {
2659 if (!event_priv->registered)
2660 register_event(event);
2661 } else {
2662 if (event_priv->registered)
2663 unregister_event(event);
2664 }
2665
2666 lttng_event_sync_filter_state(event);
2667 lttng_event_sync_capture_state(event);
2668 }
2669 }
2670
2671 /*
2672 * lttng_session_sync_event_enablers should be called just before starting a
2673 * session.
2674 */
2675 static
2676 void lttng_session_sync_event_enablers(struct lttng_kernel_session *session)
2677 {
2678 lttng_sync_event_list(&session->priv->enablers_head, &session->priv->events);
2679 }
2680
2681 /*
2682 * Apply enablers to session events, adding events to session if need
2683 * be. It is required after each modification applied to an active
2684 * session, and right before session "start".
2685 * "lazy" sync means we only sync if required.
2686 * Should be called with sessions mutex held.
2687 */
2688 static
2689 void lttng_session_lazy_sync_event_enablers(struct lttng_kernel_session *session)
2690 {
2691 /* We can skip if session is not active */
2692 if (!session->active)
2693 return;
2694 lttng_session_sync_event_enablers(session);
2695 }
2696
2697 static
2698 void lttng_event_notifier_group_sync_enablers(struct lttng_event_notifier_group *event_notifier_group)
2699 {
2700 lttng_sync_event_list(&event_notifier_group->enablers_head, &event_notifier_group->event_notifiers_head);
2701 }
2702
2703 static
2704 void lttng_event_enabler_sync(struct lttng_event_enabler_common *event_enabler)
2705 {
2706 switch (event_enabler->enabler_type) {
2707 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
2708 {
2709 struct lttng_event_recorder_enabler *event_recorder_enabler =
2710 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
2711 lttng_session_lazy_sync_event_enablers(event_recorder_enabler->chan->parent.session);
2712 break;
2713 }
2714 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
2715 {
2716 struct lttng_event_notifier_enabler *event_notifier_enabler =
2717 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
2718 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2719 break;
2720 }
2721 default:
2722 WARN_ON_ONCE(1);
2723 }
2724 }
2725
2726 /*
2727 * Serialize at most one packet worth of metadata into a metadata
2728 * channel.
2729 * We grab the metadata cache mutex to get exclusive access to our metadata
2730 * buffer and to the metadata cache. Exclusive access to the metadata buffer
2731 * allows us to do racy operations such as looking for remaining space left in
2732 * packet and write, since mutual exclusion protects us from concurrent writes.
2733 * Mutual exclusion on the metadata cache allow us to read the cache content
2734 * without racing against reallocation of the cache by updates.
2735 * Returns the number of bytes written in the channel, 0 if no data
2736 * was written and a negative value on error.
2737 */
2738 int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
2739 struct lttng_kernel_ring_buffer_channel *chan, bool *coherent)
2740 {
2741 struct lttng_kernel_ring_buffer_ctx ctx;
2742 int ret = 0;
2743 size_t len, reserve_len;
2744
2745 /*
2746 * Ensure we support mutiple get_next / put sequences followed by
2747 * put_next. The metadata cache lock protects reading the metadata
2748 * cache. It can indeed be read concurrently by "get_next_subbuf" and
2749 * "flush" operations on the buffer invoked by different processes.
2750 * Moreover, since the metadata cache memory can be reallocated, we
2751 * need to have exclusive access against updates even though we only
2752 * read it.
2753 */
2754 mutex_lock(&stream->metadata_cache->lock);
2755 WARN_ON(stream->metadata_in < stream->metadata_out);
2756 if (stream->metadata_in != stream->metadata_out)
2757 goto end;
2758
2759 /* Metadata regenerated, change the version. */
2760 if (stream->metadata_cache->version != stream->version)
2761 stream->version = stream->metadata_cache->version;
2762
2763 len = stream->metadata_cache->metadata_written -
2764 stream->metadata_in;
2765 if (!len)
2766 goto end;
2767 reserve_len = min_t(size_t,
2768 stream->transport->ops.priv->packet_avail_size(chan),
2769 len);
2770 lib_ring_buffer_ctx_init(&ctx, chan, reserve_len,
2771 sizeof(char), NULL);
2772 /*
2773 * If reservation failed, return an error to the caller.
2774 */
2775 ret = stream->transport->ops.event_reserve(&ctx);
2776 if (ret != 0) {
2777 printk(KERN_WARNING "LTTng: Metadata event reservation failed\n");
2778 stream->coherent = false;
2779 goto end;
2780 }
2781 stream->transport->ops.event_write(&ctx,
2782 stream->metadata_cache->data + stream->metadata_in,
2783 reserve_len, 1);
2784 stream->transport->ops.event_commit(&ctx);
2785 stream->metadata_in += reserve_len;
2786 if (reserve_len < len)
2787 stream->coherent = false;
2788 else
2789 stream->coherent = true;
2790 ret = reserve_len;
2791
2792 end:
2793 if (coherent)
2794 *coherent = stream->coherent;
2795 mutex_unlock(&stream->metadata_cache->lock);
2796 return ret;
2797 }
2798
2799 static
2800 void lttng_metadata_begin(struct lttng_kernel_session *session)
2801 {
2802 if (atomic_inc_return(&session->priv->metadata_cache->producing) == 1)
2803 mutex_lock(&session->priv->metadata_cache->lock);
2804 }
2805
2806 static
2807 void lttng_metadata_end(struct lttng_kernel_session *session)
2808 {
2809 WARN_ON_ONCE(!atomic_read(&session->priv->metadata_cache->producing));
2810 if (atomic_dec_return(&session->priv->metadata_cache->producing) == 0) {
2811 struct lttng_metadata_stream *stream;
2812
2813 list_for_each_entry(stream, &session->priv->metadata_cache->metadata_stream, list)
2814 wake_up_interruptible(&stream->read_wait);
2815 mutex_unlock(&session->priv->metadata_cache->lock);
2816 }
2817 }
2818
2819 /*
2820 * Write the metadata to the metadata cache.
2821 * Must be called with sessions_mutex held.
2822 * The metadata cache lock protects us from concurrent read access from
2823 * thread outputting metadata content to ring buffer.
2824 * The content of the printf is printed as a single atomic metadata
2825 * transaction.
2826 */
2827 int lttng_metadata_printf(struct lttng_kernel_session *session,
2828 const char *fmt, ...)
2829 {
2830 char *str;
2831 size_t len;
2832 va_list ap;
2833
2834 WARN_ON_ONCE(!LTTNG_READ_ONCE(session->active));
2835
2836 va_start(ap, fmt);
2837 str = kvasprintf(GFP_KERNEL, fmt, ap);
2838 va_end(ap);
2839 if (!str)
2840 return -ENOMEM;
2841
2842 len = strlen(str);
2843 WARN_ON_ONCE(!atomic_read(&session->priv->metadata_cache->producing));
2844 if (session->priv->metadata_cache->metadata_written + len >
2845 session->priv->metadata_cache->cache_alloc) {
2846 char *tmp_cache_realloc;
2847 unsigned int tmp_cache_alloc_size;
2848
2849 tmp_cache_alloc_size = max_t(unsigned int,
2850 session->priv->metadata_cache->cache_alloc + len,
2851 session->priv->metadata_cache->cache_alloc << 1);
2852 tmp_cache_realloc = vzalloc(tmp_cache_alloc_size);
2853 if (!tmp_cache_realloc)
2854 goto err;
2855 if (session->priv->metadata_cache->data) {
2856 memcpy(tmp_cache_realloc,
2857 session->priv->metadata_cache->data,
2858 session->priv->metadata_cache->cache_alloc);
2859 vfree(session->priv->metadata_cache->data);
2860 }
2861
2862 session->priv->metadata_cache->cache_alloc = tmp_cache_alloc_size;
2863 session->priv->metadata_cache->data = tmp_cache_realloc;
2864 }
2865 memcpy(session->priv->metadata_cache->data +
2866 session->priv->metadata_cache->metadata_written,
2867 str, len);
2868 session->priv->metadata_cache->metadata_written += len;
2869 kfree(str);
2870
2871 return 0;
2872
2873 err:
2874 kfree(str);
2875 return -ENOMEM;
2876 }
2877
2878 static
2879 int print_tabs(struct lttng_kernel_session *session, size_t nesting)
2880 {
2881 size_t i;
2882
2883 for (i = 0; i < nesting; i++) {
2884 int ret;
2885
2886 ret = lttng_metadata_printf(session, " ");
2887 if (ret) {
2888 return ret;
2889 }
2890 }
2891 return 0;
2892 }
2893
2894 static
2895 int lttng_field_name_statedump(struct lttng_kernel_session *session,
2896 const struct lttng_kernel_event_field *field,
2897 size_t nesting)
2898 {
2899 return lttng_metadata_printf(session, " _%s;\n", field->name);
2900 }
2901
2902 static
2903 int _lttng_integer_type_statedump(struct lttng_kernel_session *session,
2904 const struct lttng_kernel_type_integer *type,
2905 enum lttng_kernel_string_encoding parent_encoding,
2906 size_t nesting)
2907 {
2908 int ret;
2909
2910 ret = print_tabs(session, nesting);
2911 if (ret)
2912 return ret;
2913 ret = lttng_metadata_printf(session,
2914 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s }",
2915 type->size,
2916 type->alignment,
2917 type->signedness,
2918 (parent_encoding == lttng_kernel_string_encoding_none)
2919 ? "none"
2920 : (parent_encoding == lttng_kernel_string_encoding_UTF8)
2921 ? "UTF8"
2922 : "ASCII",
2923 type->base,
2924 #if __BYTE_ORDER == __BIG_ENDIAN
2925 type->reverse_byte_order ? " byte_order = le;" : ""
2926 #else
2927 type->reverse_byte_order ? " byte_order = be;" : ""
2928 #endif
2929 );
2930 return ret;
2931 }
2932
2933 /*
2934 * Must be called with sessions_mutex held.
2935 */
2936 static
2937 int _lttng_struct_type_statedump(struct lttng_kernel_session *session,
2938 const struct lttng_kernel_type_struct *type,
2939 size_t nesting)
2940 {
2941 const char *prev_field_name = NULL;
2942 int ret;
2943 uint32_t i, nr_fields;
2944 unsigned int alignment;
2945
2946 ret = print_tabs(session, nesting);
2947 if (ret)
2948 return ret;
2949 ret = lttng_metadata_printf(session,
2950 "struct {\n");
2951 if (ret)
2952 return ret;
2953 nr_fields = type->nr_fields;
2954 for (i = 0; i < nr_fields; i++) {
2955 const struct lttng_kernel_event_field *iter_field;
2956
2957 iter_field = type->fields[i];
2958 ret = _lttng_field_statedump(session, iter_field, nesting + 1, &prev_field_name);
2959 if (ret)
2960 return ret;
2961 }
2962 ret = print_tabs(session, nesting);
2963 if (ret)
2964 return ret;
2965 alignment = type->alignment;
2966 if (alignment) {
2967 ret = lttng_metadata_printf(session,
2968 "} align(%u)",
2969 alignment);
2970 } else {
2971 ret = lttng_metadata_printf(session,
2972 "}");
2973 }
2974 return ret;
2975 }
2976
2977 /*
2978 * Must be called with sessions_mutex held.
2979 */
2980 static
2981 int _lttng_struct_field_statedump(struct lttng_kernel_session *session,
2982 const struct lttng_kernel_event_field *field,
2983 size_t nesting)
2984 {
2985 int ret;
2986
2987 ret = _lttng_struct_type_statedump(session,
2988 lttng_kernel_get_type_struct(field->type), nesting);
2989 if (ret)
2990 return ret;
2991 return lttng_field_name_statedump(session, field, nesting);
2992 }
2993
2994 /*
2995 * Must be called with sessions_mutex held.
2996 */
2997 static
2998 int _lttng_variant_type_statedump(struct lttng_kernel_session *session,
2999 const struct lttng_kernel_type_variant *type,
3000 size_t nesting,
3001 const char *prev_field_name)
3002 {
3003 const char *tag_name;
3004 int ret;
3005 uint32_t i, nr_choices;
3006
3007 tag_name = type->tag_name;
3008 if (!tag_name)
3009 tag_name = prev_field_name;
3010 if (!tag_name)
3011 return -EINVAL;
3012 /*
3013 * CTF 1.8 does not allow expressing nonzero variant alignment in a nestable way.
3014 */
3015 if (type->alignment != 0)
3016 return -EINVAL;
3017 ret = print_tabs(session, nesting);
3018 if (ret)
3019 return ret;
3020 ret = lttng_metadata_printf(session,
3021 "variant <_%s> {\n",
3022 tag_name);
3023 if (ret)
3024 return ret;
3025 nr_choices = type->nr_choices;
3026 for (i = 0; i < nr_choices; i++) {
3027 const struct lttng_kernel_event_field *iter_field;
3028
3029 iter_field = type->choices[i];
3030 ret = _lttng_field_statedump(session, iter_field, nesting + 1, NULL);
3031 if (ret)
3032 return ret;
3033 }
3034 ret = print_tabs(session, nesting);
3035 if (ret)
3036 return ret;
3037 ret = lttng_metadata_printf(session,
3038 "}");
3039 return ret;
3040 }
3041
3042 /*
3043 * Must be called with sessions_mutex held.
3044 */
3045 static
3046 int _lttng_variant_field_statedump(struct lttng_kernel_session *session,
3047 const struct lttng_kernel_event_field *field,
3048 size_t nesting,
3049 const char *prev_field_name)
3050 {
3051 int ret;
3052
3053 ret = _lttng_variant_type_statedump(session,
3054 lttng_kernel_get_type_variant(field->type), nesting,
3055 prev_field_name);
3056 if (ret)
3057 return ret;
3058 return lttng_field_name_statedump(session, field, nesting);
3059 }
3060
3061 /*
3062 * Must be called with sessions_mutex held.
3063 */
3064 static
3065 int _lttng_array_field_statedump(struct lttng_kernel_session *session,
3066 const struct lttng_kernel_event_field *field,
3067 size_t nesting)
3068 {
3069 int ret;
3070 const struct lttng_kernel_type_array *array_type;
3071 const struct lttng_kernel_type_common *elem_type;
3072
3073 array_type = lttng_kernel_get_type_array(field->type);
3074 WARN_ON_ONCE(!array_type);
3075
3076 if (array_type->alignment) {
3077 ret = print_tabs(session, nesting);
3078 if (ret)
3079 return ret;
3080 ret = lttng_metadata_printf(session,
3081 "struct { } align(%u) _%s_padding;\n",
3082 array_type->alignment * CHAR_BIT,
3083 field->name);
3084 if (ret)
3085 return ret;
3086 }
3087 /*
3088 * Nested compound types: Only array of structures and variants are
3089 * currently supported.
3090 */
3091 elem_type = array_type->elem_type;
3092 switch (elem_type->type) {
3093 case lttng_kernel_type_integer:
3094 case lttng_kernel_type_struct:
3095 case lttng_kernel_type_variant:
3096 ret = _lttng_type_statedump(session, elem_type,
3097 array_type->encoding, nesting);
3098 if (ret)
3099 return ret;
3100 break;
3101
3102 default:
3103 return -EINVAL;
3104 }
3105 ret = lttng_metadata_printf(session,
3106 " _%s[%u];\n",
3107 field->name,
3108 array_type->length);
3109 return ret;
3110 }
3111
3112 /*
3113 * Must be called with sessions_mutex held.
3114 */
3115 static
3116 int _lttng_sequence_field_statedump(struct lttng_kernel_session *session,
3117 const struct lttng_kernel_event_field *field,
3118 size_t nesting,
3119 const char *prev_field_name)
3120 {
3121 int ret;
3122 const char *length_name;
3123 const struct lttng_kernel_type_sequence *sequence_type;
3124 const struct lttng_kernel_type_common *elem_type;
3125
3126 sequence_type = lttng_kernel_get_type_sequence(field->type);
3127 WARN_ON_ONCE(!sequence_type);
3128
3129 length_name = sequence_type->length_name;
3130 if (!length_name)
3131 length_name = prev_field_name;
3132 if (!length_name)
3133 return -EINVAL;
3134
3135 if (sequence_type->alignment) {
3136 ret = print_tabs(session, nesting);
3137 if (ret)
3138 return ret;
3139 ret = lttng_metadata_printf(session,
3140 "struct { } align(%u) _%s_padding;\n",
3141 sequence_type->alignment * CHAR_BIT,
3142 field->name);
3143 if (ret)
3144 return ret;
3145 }
3146
3147 /*
3148 * Nested compound types: Only array of structures and variants are
3149 * currently supported.
3150 */
3151 elem_type = sequence_type->elem_type;
3152 switch (elem_type->type) {
3153 case lttng_kernel_type_integer:
3154 case lttng_kernel_type_struct:
3155 case lttng_kernel_type_variant:
3156 ret = _lttng_type_statedump(session, elem_type,
3157 sequence_type->encoding, nesting);
3158 if (ret)
3159 return ret;
3160 break;
3161
3162 default:
3163 return -EINVAL;
3164 }
3165 ret = lttng_metadata_printf(session,
3166 " _%s[ _%s ];\n",
3167 field->name,
3168 length_name);
3169 return ret;
3170 }
3171
3172 /*
3173 * Must be called with sessions_mutex held.
3174 */
3175 static
3176 int _lttng_enum_type_statedump(struct lttng_kernel_session *session,
3177 const struct lttng_kernel_type_enum *type,
3178 size_t nesting)
3179 {
3180 const struct lttng_kernel_enum_desc *enum_desc;
3181 const struct lttng_kernel_type_common *container_type;
3182 int ret;
3183 unsigned int i, nr_entries;
3184
3185 container_type = type->container_type;
3186 if (container_type->type != lttng_kernel_type_integer) {
3187 ret = -EINVAL;
3188 goto end;
3189 }
3190 enum_desc = type->desc;
3191 nr_entries = enum_desc->nr_entries;
3192
3193 ret = print_tabs(session, nesting);
3194 if (ret)
3195 goto end;
3196 ret = lttng_metadata_printf(session, "enum : ");
3197 if (ret)
3198 goto end;
3199 ret = _lttng_integer_type_statedump(session, lttng_kernel_get_type_integer(container_type),
3200 lttng_kernel_string_encoding_none, 0);
3201 if (ret)
3202 goto end;
3203 ret = lttng_metadata_printf(session, " {\n");
3204 if (ret)
3205 goto end;
3206 /* Dump all entries */
3207 for (i = 0; i < nr_entries; i++) {
3208 const struct lttng_kernel_enum_entry *entry = enum_desc->entries[i];
3209 int j, len;
3210
3211 ret = print_tabs(session, nesting + 1);
3212 if (ret)
3213 goto end;
3214 ret = lttng_metadata_printf(session,
3215 "\"");
3216 if (ret)
3217 goto end;
3218 len = strlen(entry->string);
3219 /* Escape the character '"' */
3220 for (j = 0; j < len; j++) {
3221 char c = entry->string[j];
3222
3223 switch (c) {
3224 case '"':
3225 ret = lttng_metadata_printf(session,
3226 "\\\"");
3227 break;
3228 case '\\':
3229 ret = lttng_metadata_printf(session,
3230 "\\\\");
3231 break;
3232 default:
3233 ret = lttng_metadata_printf(session,
3234 "%c", c);
3235 break;
3236 }
3237 if (ret)
3238 goto end;
3239 }
3240 ret = lttng_metadata_printf(session, "\"");
3241 if (ret)
3242 goto end;
3243
3244 if (entry->options.is_auto) {
3245 ret = lttng_metadata_printf(session, ",\n");
3246 if (ret)
3247 goto end;
3248 } else {
3249 ret = lttng_metadata_printf(session,
3250 " = ");
3251 if (ret)
3252 goto end;
3253 if (entry->start.signedness)
3254 ret = lttng_metadata_printf(session,
3255 "%lld", (long long) entry->start.value);
3256 else
3257 ret = lttng_metadata_printf(session,
3258 "%llu", entry->start.value);
3259 if (ret)
3260 goto end;
3261 if (entry->start.signedness == entry->end.signedness &&
3262 entry->start.value
3263 == entry->end.value) {
3264 ret = lttng_metadata_printf(session,
3265 ",\n");
3266 } else {
3267 if (entry->end.signedness) {
3268 ret = lttng_metadata_printf(session,
3269 " ... %lld,\n",
3270 (long long) entry->end.value);
3271 } else {
3272 ret = lttng_metadata_printf(session,
3273 " ... %llu,\n",
3274 entry->end.value);
3275 }
3276 }
3277 if (ret)
3278 goto end;
3279 }
3280 }
3281 ret = print_tabs(session, nesting);
3282 if (ret)
3283 goto end;
3284 ret = lttng_metadata_printf(session, "}");
3285 end:
3286 return ret;
3287 }
3288
3289 /*
3290 * Must be called with sessions_mutex held.
3291 */
3292 static
3293 int _lttng_enum_field_statedump(struct lttng_kernel_session *session,
3294 const struct lttng_kernel_event_field *field,
3295 size_t nesting)
3296 {
3297 int ret;
3298 const struct lttng_kernel_type_enum *enum_type;
3299
3300 enum_type = lttng_kernel_get_type_enum(field->type);
3301 WARN_ON_ONCE(!enum_type);
3302 ret = _lttng_enum_type_statedump(session, enum_type, nesting);
3303 if (ret)
3304 return ret;
3305 return lttng_field_name_statedump(session, field, nesting);
3306 }
3307
3308 static
3309 int _lttng_integer_field_statedump(struct lttng_kernel_session *session,
3310 const struct lttng_kernel_event_field *field,
3311 size_t nesting)
3312 {
3313 int ret;
3314
3315 ret = _lttng_integer_type_statedump(session, lttng_kernel_get_type_integer(field->type),
3316 lttng_kernel_string_encoding_none, nesting);
3317 if (ret)
3318 return ret;
3319 return lttng_field_name_statedump(session, field, nesting);
3320 }
3321
3322 static
3323 int _lttng_string_type_statedump(struct lttng_kernel_session *session,
3324 const struct lttng_kernel_type_string *type,
3325 size_t nesting)
3326 {
3327 int ret;
3328
3329 /* Default encoding is UTF8 */
3330 ret = print_tabs(session, nesting);
3331 if (ret)
3332 return ret;
3333 ret = lttng_metadata_printf(session,
3334 "string%s",
3335 type->encoding == lttng_kernel_string_encoding_ASCII ?
3336 " { encoding = ASCII; }" : "");
3337 return ret;
3338 }
3339
3340 static
3341 int _lttng_string_field_statedump(struct lttng_kernel_session *session,
3342 const struct lttng_kernel_event_field *field,
3343 size_t nesting)
3344 {
3345 const struct lttng_kernel_type_string *string_type;
3346 int ret;
3347
3348 string_type = lttng_kernel_get_type_string(field->type);
3349 WARN_ON_ONCE(!string_type);
3350 ret = _lttng_string_type_statedump(session, string_type, nesting);
3351 if (ret)
3352 return ret;
3353 return lttng_field_name_statedump(session, field, nesting);
3354 }
3355
3356 /*
3357 * Must be called with sessions_mutex held.
3358 */
3359 static
3360 int _lttng_type_statedump(struct lttng_kernel_session *session,
3361 const struct lttng_kernel_type_common *type,
3362 enum lttng_kernel_string_encoding parent_encoding,
3363 size_t nesting)
3364 {
3365 int ret = 0;
3366
3367 switch (type->type) {
3368 case lttng_kernel_type_integer:
3369 ret = _lttng_integer_type_statedump(session,
3370 lttng_kernel_get_type_integer(type),
3371 parent_encoding, nesting);
3372 break;
3373 case lttng_kernel_type_enum:
3374 ret = _lttng_enum_type_statedump(session,
3375 lttng_kernel_get_type_enum(type),
3376 nesting);
3377 break;
3378 case lttng_kernel_type_string:
3379 ret = _lttng_string_type_statedump(session,
3380 lttng_kernel_get_type_string(type),
3381 nesting);
3382 break;
3383 case lttng_kernel_type_struct:
3384 ret = _lttng_struct_type_statedump(session,
3385 lttng_kernel_get_type_struct(type),
3386 nesting);
3387 break;
3388 case lttng_kernel_type_variant:
3389 ret = _lttng_variant_type_statedump(session,
3390 lttng_kernel_get_type_variant(type),
3391 nesting, NULL);
3392 break;
3393
3394 /* Nested arrays and sequences are not supported yet. */
3395 case lttng_kernel_type_array:
3396 case lttng_kernel_type_sequence:
3397 default:
3398 WARN_ON_ONCE(1);
3399 return -EINVAL;
3400 }
3401 return ret;
3402 }
3403
3404 /*
3405 * Must be called with sessions_mutex held.
3406 */
3407 static
3408 int _lttng_field_statedump(struct lttng_kernel_session *session,
3409 const struct lttng_kernel_event_field *field,
3410 size_t nesting,
3411 const char **prev_field_name_p)
3412 {
3413 const char *prev_field_name = NULL;
3414 int ret = 0;
3415
3416 if (prev_field_name_p)
3417 prev_field_name = *prev_field_name_p;
3418 switch (field->type->type) {
3419 case lttng_kernel_type_integer:
3420 ret = _lttng_integer_field_statedump(session, field, nesting);
3421 break;
3422 case lttng_kernel_type_enum:
3423 ret = _lttng_enum_field_statedump(session, field, nesting);
3424 break;
3425 case lttng_kernel_type_string:
3426 ret = _lttng_string_field_statedump(session, field, nesting);
3427 break;
3428 case lttng_kernel_type_struct:
3429 ret = _lttng_struct_field_statedump(session, field, nesting);
3430 break;
3431 case lttng_kernel_type_array:
3432 ret = _lttng_array_field_statedump(session, field, nesting);
3433 break;
3434 case lttng_kernel_type_sequence:
3435 ret = _lttng_sequence_field_statedump(session, field, nesting, prev_field_name);
3436 break;
3437 case lttng_kernel_type_variant:
3438 ret = _lttng_variant_field_statedump(session, field, nesting, prev_field_name);
3439 break;
3440
3441 default:
3442 WARN_ON_ONCE(1);
3443 return -EINVAL;
3444 }
3445 if (prev_field_name_p)
3446 *prev_field_name_p = field->name;
3447 return ret;
3448 }
3449
3450 static
3451 int _lttng_context_metadata_statedump(struct lttng_kernel_session *session,
3452 struct lttng_kernel_ctx *ctx)
3453 {
3454 const char *prev_field_name = NULL;
3455 int ret = 0;
3456 int i;
3457
3458 if (!ctx)
3459 return 0;
3460 for (i = 0; i < ctx->nr_fields; i++) {
3461 const struct lttng_kernel_ctx_field *field = &ctx->fields[i];
3462
3463 ret = _lttng_field_statedump(session, field->event_field, 2, &prev_field_name);
3464 if (ret)
3465 return ret;
3466 }
3467 return ret;
3468 }
3469
3470 static
3471 int _lttng_fields_metadata_statedump(struct lttng_kernel_session *session,
3472 struct lttng_kernel_event_recorder *event_recorder)
3473 {
3474 const char *prev_field_name = NULL;
3475 const struct lttng_kernel_event_desc *desc = event_recorder->priv->parent.desc;
3476 int ret = 0;
3477 int i;
3478
3479 for (i = 0; i < desc->tp_class->nr_fields; i++) {
3480 const struct lttng_kernel_event_field *field = desc->tp_class->fields[i];
3481
3482 ret = _lttng_field_statedump(session, field, 2, &prev_field_name);
3483 if (ret)
3484 return ret;
3485 }
3486 return ret;
3487 }
3488
3489 /*
3490 * Must be called with sessions_mutex held.
3491 * The entire event metadata is printed as a single atomic metadata
3492 * transaction.
3493 */
3494 static
3495 int _lttng_event_recorder_metadata_statedump(struct lttng_kernel_event_common *event)
3496 {
3497 struct lttng_kernel_event_recorder *event_recorder;
3498 struct lttng_kernel_channel_buffer *chan;
3499 struct lttng_kernel_session *session;
3500 int ret = 0;
3501
3502 if (event->type != LTTNG_KERNEL_EVENT_TYPE_RECORDER)
3503 return 0;
3504 event_recorder = container_of(event, struct lttng_kernel_event_recorder, parent);
3505 chan = event_recorder->chan;
3506 session = chan->parent.session;
3507
3508 if (event_recorder->priv->metadata_dumped || !LTTNG_READ_ONCE(session->active))
3509 return 0;
3510 if (chan->priv->channel_type == METADATA_CHANNEL)
3511 return 0;
3512
3513 lttng_metadata_begin(session);
3514
3515 ret = lttng_metadata_printf(session,
3516 "event {\n"
3517 " name = \"%s\";\n"
3518 " id = %u;\n"
3519 " stream_id = %u;\n",
3520 event_recorder->priv->parent.desc->event_name,
3521 event_recorder->priv->id,
3522 event_recorder->chan->priv->id);
3523 if (ret)
3524 goto end;
3525
3526 ret = lttng_metadata_printf(session,
3527 " fields := struct {\n"
3528 );
3529 if (ret)
3530 goto end;
3531
3532 ret = _lttng_fields_metadata_statedump(session, event_recorder);
3533 if (ret)
3534 goto end;
3535
3536 /*
3537 * LTTng space reservation can only reserve multiples of the
3538 * byte size.
3539 */
3540 ret = lttng_metadata_printf(session,
3541 " };\n"
3542 "};\n\n");
3543 if (ret)
3544 goto end;
3545
3546 event_recorder->priv->metadata_dumped = 1;
3547 end:
3548 lttng_metadata_end(session);
3549 return ret;
3550
3551 }
3552
3553 /*
3554 * Must be called with sessions_mutex held.
3555 * The entire channel metadata is printed as a single atomic metadata
3556 * transaction.
3557 */
3558 static
3559 int _lttng_channel_metadata_statedump(struct lttng_kernel_session *session,
3560 struct lttng_kernel_channel_buffer *chan)
3561 {
3562 int ret = 0;
3563
3564 if (chan->priv->metadata_dumped || !LTTNG_READ_ONCE(session->active))
3565 return 0;
3566
3567 if (chan->priv->channel_type == METADATA_CHANNEL)
3568 return 0;
3569
3570 lttng_metadata_begin(session);
3571
3572 WARN_ON_ONCE(!chan->priv->header_type);
3573 ret = lttng_metadata_printf(session,
3574 "stream {\n"
3575 " id = %u;\n"
3576 " event.header := %s;\n"
3577 " packet.context := struct packet_context;\n",
3578 chan->priv->id,
3579 chan->priv->header_type == 1 ? "struct event_header_compact" :
3580 "struct event_header_large");
3581 if (ret)
3582 goto end;
3583
3584 if (chan->priv->ctx) {
3585 ret = lttng_metadata_printf(session,
3586 " event.context := struct {\n");
3587 if (ret)
3588 goto end;
3589 }
3590 ret = _lttng_context_metadata_statedump(session, chan->priv->ctx);
3591 if (ret)
3592 goto end;
3593 if (chan->priv->ctx) {
3594 ret = lttng_metadata_printf(session,
3595 " };\n");
3596 if (ret)
3597 goto end;
3598 }
3599
3600 ret = lttng_metadata_printf(session,
3601 "};\n\n");
3602
3603 chan->priv->metadata_dumped = 1;
3604 end:
3605 lttng_metadata_end(session);
3606 return ret;
3607 }
3608
3609 /*
3610 * Must be called with sessions_mutex held.
3611 */
3612 static
3613 int _lttng_stream_packet_context_declare(struct lttng_kernel_session *session)
3614 {
3615 return lttng_metadata_printf(session,
3616 "struct packet_context {\n"
3617 " uint64_clock_monotonic_t timestamp_begin;\n"
3618 " uint64_clock_monotonic_t timestamp_end;\n"
3619 " uint64_t content_size;\n"
3620 " uint64_t packet_size;\n"
3621 " uint64_t packet_seq_num;\n"
3622 " unsigned long events_discarded;\n"
3623 " uint32_t cpu_id;\n"
3624 "};\n\n"
3625 );
3626 }
3627
3628 /*
3629 * Compact header:
3630 * id: range: 0 - 30.
3631 * id 31 is reserved to indicate an extended header.
3632 *
3633 * Large header:
3634 * id: range: 0 - 65534.
3635 * id 65535 is reserved to indicate an extended header.
3636 *
3637 * Must be called with sessions_mutex held.
3638 */
3639 static
3640 int _lttng_event_header_declare(struct lttng_kernel_session *session)
3641 {
3642 return lttng_metadata_printf(session,
3643 "struct event_header_compact {\n"
3644 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
3645 " variant <id> {\n"
3646 " struct {\n"
3647 " uint27_clock_monotonic_t timestamp;\n"
3648 " } compact;\n"
3649 " struct {\n"
3650 " uint32_t id;\n"
3651 " uint64_clock_monotonic_t timestamp;\n"
3652 " } extended;\n"
3653 " } v;\n"
3654 "} align(%u);\n"
3655 "\n"
3656 "struct event_header_large {\n"
3657 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
3658 " variant <id> {\n"
3659 " struct {\n"
3660 " uint32_clock_monotonic_t timestamp;\n"
3661 " } compact;\n"
3662 " struct {\n"
3663 " uint32_t id;\n"
3664 " uint64_clock_monotonic_t timestamp;\n"
3665 " } extended;\n"
3666 " } v;\n"
3667 "} align(%u);\n\n",
3668 lttng_alignof(uint32_t) * CHAR_BIT,
3669 lttng_alignof(uint16_t) * CHAR_BIT
3670 );
3671 }
3672
3673 /*
3674 * Approximation of NTP time of day to clock monotonic correlation,
3675 * taken at start of trace.
3676 * Yes, this is only an approximation. Yes, we can (and will) do better
3677 * in future versions.
3678 * This function may return a negative offset. It may happen if the
3679 * system sets the REALTIME clock to 0 after boot.
3680 *
3681 * Use 64bit timespec on kernels that have it, this makes 32bit arch
3682 * y2038 compliant.
3683 */
3684 static
3685 int64_t measure_clock_offset(void)
3686 {
3687 uint64_t monotonic_avg, monotonic[2], realtime;
3688 uint64_t tcf = trace_clock_freq();
3689 int64_t offset;
3690 unsigned long flags;
3691 #ifdef LTTNG_KERNEL_HAS_TIMESPEC64
3692 struct timespec64 rts = { 0, 0 };
3693 #else
3694 struct timespec rts = { 0, 0 };
3695 #endif
3696
3697 /* Disable interrupts to increase correlation precision. */
3698 local_irq_save(flags);
3699 monotonic[0] = trace_clock_read64();
3700 #ifdef LTTNG_KERNEL_HAS_TIMESPEC64
3701 ktime_get_real_ts64(&rts);
3702 #else
3703 getnstimeofday(&rts);
3704 #endif
3705 monotonic[1] = trace_clock_read64();
3706 local_irq_restore(flags);
3707
3708 monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
3709 realtime = (uint64_t) rts.tv_sec * tcf;
3710 if (tcf == NSEC_PER_SEC) {
3711 realtime += rts.tv_nsec;
3712 } else {
3713 uint64_t n = rts.tv_nsec * tcf;
3714
3715 do_div(n, NSEC_PER_SEC);
3716 realtime += n;
3717 }
3718 offset = (int64_t) realtime - monotonic_avg;
3719 return offset;
3720 }
3721
3722 static
3723 int print_escaped_ctf_string(struct lttng_kernel_session *session, const char *string)
3724 {
3725 int ret = 0;
3726 size_t i;
3727 char cur;
3728
3729 i = 0;
3730 cur = string[i];
3731 while (cur != '\0') {
3732 switch (cur) {
3733 case '\n':
3734 ret = lttng_metadata_printf(session, "%s", "\\n");
3735 break;
3736 case '\\':
3737 case '"':
3738 ret = lttng_metadata_printf(session, "%c", '\\');
3739 if (ret)
3740 goto error;
3741 /* We still print the current char */
3742 lttng_fallthrough;
3743 default:
3744 ret = lttng_metadata_printf(session, "%c", cur);
3745 break;
3746 }
3747
3748 if (ret)
3749 goto error;
3750
3751 cur = string[++i];
3752 }
3753 error:
3754 return ret;
3755 }
3756
3757 static
3758 int print_metadata_escaped_field(struct lttng_kernel_session *session, const char *field,
3759 const char *field_value)
3760 {
3761 int ret;
3762
3763 ret = lttng_metadata_printf(session, " %s = \"", field);
3764 if (ret)
3765 goto error;
3766
3767 ret = print_escaped_ctf_string(session, field_value);
3768 if (ret)
3769 goto error;
3770
3771 ret = lttng_metadata_printf(session, "\";\n");
3772
3773 error:
3774 return ret;
3775 }
3776
3777 /*
3778 * Output metadata into this session's metadata buffers.
3779 * Must be called with sessions_mutex held.
3780 */
3781 static
3782 int _lttng_session_metadata_statedump(struct lttng_kernel_session *session)
3783 {
3784 unsigned char *uuid_c = session->priv->uuid.b;
3785 unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN];
3786 const char *product_uuid;
3787 struct lttng_kernel_channel_buffer_private *chan_priv;
3788 struct lttng_kernel_event_recorder_private *event_recorder_priv;
3789 int ret = 0;
3790
3791 if (!LTTNG_READ_ONCE(session->active))
3792 return 0;
3793
3794 lttng_metadata_begin(session);
3795
3796 if (session->priv->metadata_dumped)
3797 goto skip_session;
3798
3799 snprintf(uuid_s, sizeof(uuid_s),
3800 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
3801 uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3],
3802 uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7],
3803 uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11],
3804 uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]);
3805
3806 ret = lttng_metadata_printf(session,
3807 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
3808 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
3809 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
3810 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
3811 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
3812 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
3813 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
3814 "\n"
3815 "trace {\n"
3816 " major = %u;\n"
3817 " minor = %u;\n"
3818 " uuid = \"%s\";\n"
3819 " byte_order = %s;\n"
3820 " packet.header := struct {\n"
3821 " uint32_t magic;\n"
3822 " uint8_t uuid[16];\n"
3823 " uint32_t stream_id;\n"
3824 " uint64_t stream_instance_id;\n"
3825 " };\n"
3826 "};\n\n",
3827 lttng_alignof(uint8_t) * CHAR_BIT,
3828 lttng_alignof(uint16_t) * CHAR_BIT,
3829 lttng_alignof(uint32_t) * CHAR_BIT,
3830 lttng_alignof(uint64_t) * CHAR_BIT,
3831 sizeof(unsigned long) * CHAR_BIT,
3832 lttng_alignof(unsigned long) * CHAR_BIT,
3833 CTF_SPEC_MAJOR,
3834 CTF_SPEC_MINOR,
3835 uuid_s,
3836 #if __BYTE_ORDER == __BIG_ENDIAN
3837 "be"
3838 #else
3839 "le"
3840 #endif
3841 );
3842 if (ret)
3843 goto end;
3844
3845 ret = lttng_metadata_printf(session,
3846 "env {\n"
3847 " hostname = \"%s\";\n"
3848 " domain = \"kernel\";\n"
3849 " sysname = \"%s\";\n"
3850 " kernel_release = \"%s\";\n"
3851 " kernel_version = \"%s\";\n"
3852 " tracer_name = \"lttng-modules\";\n"
3853 " tracer_major = %d;\n"
3854 " tracer_minor = %d;\n"
3855 " tracer_patchlevel = %d;\n"
3856 " trace_buffering_scheme = \"global\";\n",
3857 current->nsproxy->uts_ns->name.nodename,
3858 utsname()->sysname,
3859 utsname()->release,
3860 utsname()->version,
3861 LTTNG_MODULES_MAJOR_VERSION,
3862 LTTNG_MODULES_MINOR_VERSION,
3863 LTTNG_MODULES_PATCHLEVEL_VERSION
3864 );
3865 if (ret)
3866 goto end;
3867
3868 ret = print_metadata_escaped_field(session, "trace_name", session->priv->name);
3869 if (ret)
3870 goto end;
3871 ret = print_metadata_escaped_field(session, "trace_creation_datetime",
3872 session->priv->creation_time);
3873 if (ret)
3874 goto end;
3875
3876 /* Add the product UUID to the 'env' section */
3877 product_uuid = dmi_get_system_info(DMI_PRODUCT_UUID);
3878 if (product_uuid) {
3879 ret = lttng_metadata_printf(session,
3880 " product_uuid = \"%s\";\n",
3881 product_uuid
3882 );
3883 if (ret)
3884 goto end;
3885 }
3886
3887 /* Close the 'env' section */
3888 ret = lttng_metadata_printf(session, "};\n\n");
3889 if (ret)
3890 goto end;
3891
3892 ret = lttng_metadata_printf(session,
3893 "clock {\n"
3894 " name = \"%s\";\n",
3895 trace_clock_name()
3896 );
3897 if (ret)
3898 goto end;
3899
3900 if (!trace_clock_uuid(clock_uuid_s)) {
3901 ret = lttng_metadata_printf(session,
3902 " uuid = \"%s\";\n",
3903 clock_uuid_s
3904 );
3905 if (ret)
3906 goto end;
3907 }
3908
3909 ret = lttng_metadata_printf(session,
3910 " description = \"%s\";\n"
3911 " freq = %llu; /* Frequency, in Hz */\n"
3912 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
3913 " offset = %lld;\n"
3914 "};\n\n",
3915 trace_clock_description(),
3916 (unsigned long long) trace_clock_freq(),
3917 (long long) measure_clock_offset()
3918 );
3919 if (ret)
3920 goto end;
3921
3922 ret = lttng_metadata_printf(session,
3923 "typealias integer {\n"
3924 " size = 27; align = 1; signed = false;\n"
3925 " map = clock.%s.value;\n"
3926 "} := uint27_clock_monotonic_t;\n"
3927 "\n"
3928 "typealias integer {\n"
3929 " size = 32; align = %u; signed = false;\n"
3930 " map = clock.%s.value;\n"
3931 "} := uint32_clock_monotonic_t;\n"
3932 "\n"
3933 "typealias integer {\n"
3934 " size = 64; align = %u; signed = false;\n"
3935 " map = clock.%s.value;\n"
3936 "} := uint64_clock_monotonic_t;\n\n",
3937 trace_clock_name(),
3938 lttng_alignof(uint32_t) * CHAR_BIT,
3939 trace_clock_name(),
3940 lttng_alignof(uint64_t) * CHAR_BIT,
3941 trace_clock_name()
3942 );
3943 if (ret)
3944 goto end;
3945
3946 ret = _lttng_stream_packet_context_declare(session);
3947 if (ret)
3948 goto end;
3949
3950 ret = _lttng_event_header_declare(session);
3951 if (ret)
3952 goto end;
3953
3954 skip_session:
3955 list_for_each_entry(chan_priv, &session->priv->chan, node) {
3956 ret = _lttng_channel_metadata_statedump(session, chan_priv->pub);
3957 if (ret)
3958 goto end;
3959 }
3960
3961 list_for_each_entry(event_recorder_priv, &session->priv->events, parent.node) {
3962 ret = _lttng_event_recorder_metadata_statedump(&event_recorder_priv->pub->parent);
3963 if (ret)
3964 goto end;
3965 }
3966 session->priv->metadata_dumped = 1;
3967 end:
3968 lttng_metadata_end(session);
3969 return ret;
3970 }
3971
3972 /**
3973 * lttng_transport_register - LTT transport registration
3974 * @transport: transport structure
3975 *
3976 * Registers a transport which can be used as output to extract the data out of
3977 * LTTng. The module calling this registration function must ensure that no
3978 * trap-inducing code will be executed by the transport functions. E.g.
3979 * vmalloc_sync_mappings() must be called between a vmalloc and the moment the memory
3980 * is made visible to the transport function. This registration acts as a
3981 * vmalloc_sync_mappings. Therefore, only if the module allocates virtual memory
3982 * after its registration must it synchronize the TLBs.
3983 */
3984 void lttng_transport_register(struct lttng_transport *transport)
3985 {
3986 /*
3987 * Make sure no page fault can be triggered by the module about to be
3988 * registered. We deal with this here so we don't have to call
3989 * vmalloc_sync_mappings() in each module's init.
3990 */
3991 wrapper_vmalloc_sync_mappings();
3992
3993 mutex_lock(&sessions_mutex);
3994 list_add_tail(&transport->node, &lttng_transport_list);
3995 mutex_unlock(&sessions_mutex);
3996 }
3997 EXPORT_SYMBOL_GPL(lttng_transport_register);
3998
3999 /**
4000 * lttng_transport_unregister - LTT transport unregistration
4001 * @transport: transport structure
4002 */
4003 void lttng_transport_unregister(struct lttng_transport *transport)
4004 {
4005 mutex_lock(&sessions_mutex);
4006 list_del(&transport->node);
4007 mutex_unlock(&sessions_mutex);
4008 }
4009 EXPORT_SYMBOL_GPL(lttng_transport_unregister);
4010
4011 void lttng_counter_transport_register(struct lttng_counter_transport *transport)
4012 {
4013 /*
4014 * Make sure no page fault can be triggered by the module about to be
4015 * registered. We deal with this here so we don't have to call
4016 * vmalloc_sync_mappings() in each module's init.
4017 */
4018 wrapper_vmalloc_sync_mappings();
4019
4020 mutex_lock(&sessions_mutex);
4021 list_add_tail(&transport->node, &lttng_counter_transport_list);
4022 mutex_unlock(&sessions_mutex);
4023 }
4024 EXPORT_SYMBOL_GPL(lttng_counter_transport_register);
4025
4026 void lttng_counter_transport_unregister(struct lttng_counter_transport *transport)
4027 {
4028 mutex_lock(&sessions_mutex);
4029 list_del(&transport->node);
4030 mutex_unlock(&sessions_mutex);
4031 }
4032 EXPORT_SYMBOL_GPL(lttng_counter_transport_unregister);
4033
4034 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0))
4035
4036 enum cpuhp_state lttng_hp_prepare;
4037 enum cpuhp_state lttng_hp_online;
4038
4039 static int lttng_hotplug_prepare(unsigned int cpu, struct hlist_node *node)
4040 {
4041 struct lttng_cpuhp_node *lttng_node;
4042
4043 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4044 switch (lttng_node->component) {
4045 case LTTNG_RING_BUFFER_FRONTEND:
4046 return 0;
4047 case LTTNG_RING_BUFFER_BACKEND:
4048 return lttng_cpuhp_rb_backend_prepare(cpu, lttng_node);
4049 case LTTNG_RING_BUFFER_ITER:
4050 return 0;
4051 case LTTNG_CONTEXT_PERF_COUNTERS:
4052 return 0;
4053 default:
4054 return -EINVAL;
4055 }
4056 }
4057
4058 static int lttng_hotplug_dead(unsigned int cpu, struct hlist_node *node)
4059 {
4060 struct lttng_cpuhp_node *lttng_node;
4061
4062 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4063 switch (lttng_node->component) {
4064 case LTTNG_RING_BUFFER_FRONTEND:
4065 return lttng_cpuhp_rb_frontend_dead(cpu, lttng_node);
4066 case LTTNG_RING_BUFFER_BACKEND:
4067 return 0;
4068 case LTTNG_RING_BUFFER_ITER:
4069 return 0;
4070 case LTTNG_CONTEXT_PERF_COUNTERS:
4071 return lttng_cpuhp_perf_counter_dead(cpu, lttng_node);
4072 default:
4073 return -EINVAL;
4074 }
4075 }
4076
4077 static int lttng_hotplug_online(unsigned int cpu, struct hlist_node *node)
4078 {
4079 struct lttng_cpuhp_node *lttng_node;
4080
4081 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4082 switch (lttng_node->component) {
4083 case LTTNG_RING_BUFFER_FRONTEND:
4084 return lttng_cpuhp_rb_frontend_online(cpu, lttng_node);
4085 case LTTNG_RING_BUFFER_BACKEND:
4086 return 0;
4087 case LTTNG_RING_BUFFER_ITER:
4088 return lttng_cpuhp_rb_iter_online(cpu, lttng_node);
4089 case LTTNG_CONTEXT_PERF_COUNTERS:
4090 return lttng_cpuhp_perf_counter_online(cpu, lttng_node);
4091 default:
4092 return -EINVAL;
4093 }
4094 }
4095
4096 static int lttng_hotplug_offline(unsigned int cpu, struct hlist_node *node)
4097 {
4098 struct lttng_cpuhp_node *lttng_node;
4099
4100 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4101 switch (lttng_node->component) {
4102 case LTTNG_RING_BUFFER_FRONTEND:
4103 return lttng_cpuhp_rb_frontend_offline(cpu, lttng_node);
4104 case LTTNG_RING_BUFFER_BACKEND:
4105 return 0;
4106 case LTTNG_RING_BUFFER_ITER:
4107 return 0;
4108 case LTTNG_CONTEXT_PERF_COUNTERS:
4109 return 0;
4110 default:
4111 return -EINVAL;
4112 }
4113 }
4114
4115 static int __init lttng_init_cpu_hotplug(void)
4116 {
4117 int ret;
4118
4119 ret = cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN, "lttng:prepare",
4120 lttng_hotplug_prepare,
4121 lttng_hotplug_dead);
4122 if (ret < 0) {
4123 return ret;
4124 }
4125 lttng_hp_prepare = ret;
4126 lttng_rb_set_hp_prepare(ret);
4127
4128 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "lttng:online",
4129 lttng_hotplug_online,
4130 lttng_hotplug_offline);
4131 if (ret < 0) {
4132 cpuhp_remove_multi_state(lttng_hp_prepare);
4133 lttng_hp_prepare = 0;
4134 return ret;
4135 }
4136 lttng_hp_online = ret;
4137 lttng_rb_set_hp_online(ret);
4138
4139 return 0;
4140 }
4141
4142 static void __exit lttng_exit_cpu_hotplug(void)
4143 {
4144 lttng_rb_set_hp_online(0);
4145 cpuhp_remove_multi_state(lttng_hp_online);
4146 lttng_rb_set_hp_prepare(0);
4147 cpuhp_remove_multi_state(lttng_hp_prepare);
4148 }
4149
4150 #else /* #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
4151 static int lttng_init_cpu_hotplug(void)
4152 {
4153 return 0;
4154 }
4155 static void lttng_exit_cpu_hotplug(void)
4156 {
4157 }
4158 #endif /* #else #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
4159
4160 static int __init lttng_events_init(void)
4161 {
4162 int ret;
4163
4164 ret = wrapper_lttng_fixup_sig(THIS_MODULE);
4165 if (ret)
4166 return ret;
4167 ret = wrapper_get_pfnblock_flags_mask_init();
4168 if (ret)
4169 return ret;
4170 ret = wrapper_get_pageblock_flags_mask_init();
4171 if (ret)
4172 return ret;
4173 ret = lttng_probes_init();
4174 if (ret)
4175 return ret;
4176 ret = lttng_context_init();
4177 if (ret)
4178 return ret;
4179 ret = lttng_tracepoint_init();
4180 if (ret)
4181 goto error_tp;
4182 event_recorder_cache = KMEM_CACHE(lttng_kernel_event_recorder, 0);
4183 if (!event_recorder_cache) {
4184 ret = -ENOMEM;
4185 goto error_kmem_event_recorder;
4186 }
4187 event_recorder_private_cache = KMEM_CACHE(lttng_kernel_event_recorder_private, 0);
4188 if (!event_recorder_private_cache) {
4189 ret = -ENOMEM;
4190 goto error_kmem_event_recorder_private;
4191 }
4192 event_notifier_cache = KMEM_CACHE(lttng_kernel_event_notifier, 0);
4193 if (!event_notifier_cache) {
4194 ret = -ENOMEM;
4195 goto error_kmem_event_notifier;
4196 }
4197 event_notifier_private_cache = KMEM_CACHE(lttng_kernel_event_notifier_private, 0);
4198 if (!event_notifier_private_cache) {
4199 ret = -ENOMEM;
4200 goto error_kmem_event_notifier_private;
4201 }
4202 ret = lttng_abi_init();
4203 if (ret)
4204 goto error_abi;
4205 ret = lttng_logger_init();
4206 if (ret)
4207 goto error_logger;
4208 ret = lttng_init_cpu_hotplug();
4209 if (ret)
4210 goto error_hotplug;
4211 printk(KERN_NOTICE "LTTng: Loaded modules v%s.%s.%s%s (%s)%s%s\n",
4212 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4213 __stringify(LTTNG_MODULES_MINOR_VERSION),
4214 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4215 LTTNG_MODULES_EXTRAVERSION,
4216 LTTNG_VERSION_NAME,
4217 #ifdef LTTNG_EXTRA_VERSION_GIT
4218 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4219 #else
4220 "",
4221 #endif
4222 #ifdef LTTNG_EXTRA_VERSION_NAME
4223 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4224 #else
4225 "");
4226 #endif
4227 #ifdef CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM
4228 printk(KERN_NOTICE "LTTng: Experimental bitwise enum enabled.\n");
4229 #endif /* CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM */
4230 return 0;
4231
4232 error_hotplug:
4233 lttng_logger_exit();
4234 error_logger:
4235 lttng_abi_exit();
4236 error_abi:
4237 kmem_cache_destroy(event_notifier_private_cache);
4238 error_kmem_event_notifier_private:
4239 kmem_cache_destroy(event_notifier_cache);
4240 error_kmem_event_notifier:
4241 kmem_cache_destroy(event_recorder_private_cache);
4242 error_kmem_event_recorder_private:
4243 kmem_cache_destroy(event_recorder_cache);
4244 error_kmem_event_recorder:
4245 lttng_tracepoint_exit();
4246 error_tp:
4247 lttng_context_exit();
4248 printk(KERN_NOTICE "LTTng: Failed to load modules v%s.%s.%s%s (%s)%s%s\n",
4249 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4250 __stringify(LTTNG_MODULES_MINOR_VERSION),
4251 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4252 LTTNG_MODULES_EXTRAVERSION,
4253 LTTNG_VERSION_NAME,
4254 #ifdef LTTNG_EXTRA_VERSION_GIT
4255 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4256 #else
4257 "",
4258 #endif
4259 #ifdef LTTNG_EXTRA_VERSION_NAME
4260 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4261 #else
4262 "");
4263 #endif
4264 return ret;
4265 }
4266
4267 module_init(lttng_events_init);
4268
4269 static void __exit lttng_events_exit(void)
4270 {
4271 struct lttng_kernel_session_private *session_priv, *tmpsession_priv;
4272
4273 lttng_exit_cpu_hotplug();
4274 lttng_logger_exit();
4275 lttng_abi_exit();
4276 list_for_each_entry_safe(session_priv, tmpsession_priv, &sessions, list)
4277 lttng_session_destroy(session_priv->pub);
4278 kmem_cache_destroy(event_recorder_cache);
4279 kmem_cache_destroy(event_recorder_private_cache);
4280 kmem_cache_destroy(event_notifier_cache);
4281 kmem_cache_destroy(event_notifier_private_cache);
4282 lttng_tracepoint_exit();
4283 lttng_context_exit();
4284 printk(KERN_NOTICE "LTTng: Unloaded modules v%s.%s.%s%s (%s)%s%s\n",
4285 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4286 __stringify(LTTNG_MODULES_MINOR_VERSION),
4287 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4288 LTTNG_MODULES_EXTRAVERSION,
4289 LTTNG_VERSION_NAME,
4290 #ifdef LTTNG_EXTRA_VERSION_GIT
4291 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4292 #else
4293 "",
4294 #endif
4295 #ifdef LTTNG_EXTRA_VERSION_NAME
4296 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4297 #else
4298 "");
4299 #endif
4300 }
4301
4302 module_exit(lttng_events_exit);
4303
4304 #include <generated/patches.h>
4305 #ifdef LTTNG_EXTRA_VERSION_GIT
4306 MODULE_INFO(extra_version_git, LTTNG_EXTRA_VERSION_GIT);
4307 #endif
4308 #ifdef LTTNG_EXTRA_VERSION_NAME
4309 MODULE_INFO(extra_version_name, LTTNG_EXTRA_VERSION_NAME);
4310 #endif
4311 MODULE_LICENSE("GPL and additional rights");
4312 MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
4313 MODULE_DESCRIPTION("LTTng tracer");
4314 MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
4315 __stringify(LTTNG_MODULES_MINOR_VERSION) "."
4316 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
4317 LTTNG_MODULES_EXTRAVERSION);
LTTng 2.0/0.x modules
This page took 0.185749 seconds and 5 git commands to generate.