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Refactoring: event notifier create: use enablers
[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 <wrapper/file.h>
27 #include <linux/uaccess.h>
28 #include <linux/vmalloc.h>
29 #include <linux/dmi.h>
30
31 #include <wrapper/compiler_attributes.h>
32 #include <wrapper/uuid.h>
33 #include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
34 #include <wrapper/random.h>
35 #include <wrapper/tracepoint.h>
36 #include <wrapper/list.h>
37 #include <wrapper/types.h>
38 #include <lttng/kernel-version.h>
39 #include <lttng/events.h>
40 #include <lttng/events-internal.h>
41 #include <lttng/lttng-bytecode.h>
42 #include <lttng/tracer.h>
43 #include <lttng/event-notifier-notification.h>
44 #include <lttng/abi-old.h>
45 #include <lttng/endian.h>
46 #include <lttng/string-utils.h>
47 #include <lttng/utils.h>
48 #include <ringbuffer/backend.h>
49 #include <ringbuffer/frontend.h>
50 #include <wrapper/time.h>
51
52 #define METADATA_CACHE_DEFAULT_SIZE 4096
53
54 static LIST_HEAD(sessions);
55 static LIST_HEAD(event_notifier_groups);
56 static LIST_HEAD(lttng_transport_list);
57 static LIST_HEAD(lttng_counter_transport_list);
58 /*
59 * Protect the sessions and metadata caches.
60 */
61 static DEFINE_MUTEX(sessions_mutex);
62 static struct kmem_cache *event_recorder_cache;
63 static struct kmem_cache *event_recorder_private_cache;
64 static struct kmem_cache *event_notifier_cache;
65 static struct kmem_cache *event_notifier_private_cache;
66
67 static void lttng_session_lazy_sync_event_enablers(struct lttng_kernel_session *session);
68 static void lttng_session_sync_event_enablers(struct lttng_kernel_session *session);
69 static void lttng_event_notifier_group_sync_enablers(struct lttng_event_notifier_group *event_notifier_group);
70 static void lttng_event_enabler_sync(struct lttng_event_enabler_common *event_enabler);
71
72 static void _lttng_event_destroy(struct lttng_kernel_event_common *event);
73 static void _lttng_channel_destroy(struct lttng_kernel_channel_buffer *chan);
74 static int _lttng_event_unregister(struct lttng_kernel_event_common *event);
75 static
76 int _lttng_event_metadata_statedump(struct lttng_kernel_session *session,
77 struct lttng_kernel_channel_buffer *chan,
78 struct lttng_kernel_event_recorder *event);
79 static
80 int _lttng_session_metadata_statedump(struct lttng_kernel_session *session);
81 static
82 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream);
83 static
84 int _lttng_type_statedump(struct lttng_kernel_session *session,
85 const struct lttng_kernel_type_common *type,
86 enum lttng_kernel_string_encoding parent_encoding,
87 size_t nesting);
88 static
89 int _lttng_field_statedump(struct lttng_kernel_session *session,
90 const struct lttng_kernel_event_field *field,
91 size_t nesting, const char **prev_field_name_p);
92
93 void synchronize_trace(void)
94 {
95 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,1,0) || \
96 LTTNG_RHEL_KERNEL_RANGE(4,18,0,193,0,0, 4,19,0,0,0,0))
97 synchronize_rcu();
98 #else
99 synchronize_sched();
100 #endif
101
102 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0))
103 #ifdef CONFIG_PREEMPT_RT_FULL
104 synchronize_rcu();
105 #endif
106 #else /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
107 #ifdef CONFIG_PREEMPT_RT
108 synchronize_rcu();
109 #endif
110 #endif /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
111 }
112
113 void lttng_lock_sessions(void)
114 {
115 mutex_lock(&sessions_mutex);
116 }
117
118 void lttng_unlock_sessions(void)
119 {
120 mutex_unlock(&sessions_mutex);
121 }
122
123 static struct lttng_transport *lttng_transport_find(const char *name)
124 {
125 struct lttng_transport *transport;
126
127 list_for_each_entry(transport, &lttng_transport_list, node) {
128 if (!strcmp(transport->name, name))
129 return transport;
130 }
131 return NULL;
132 }
133
134 /*
135 * Called with sessions lock held.
136 */
137 int lttng_session_active(void)
138 {
139 struct lttng_kernel_session_private *iter;
140
141 list_for_each_entry(iter, &sessions, list) {
142 if (iter->pub->active)
143 return 1;
144 }
145 return 0;
146 }
147
148 struct lttng_kernel_session *lttng_session_create(void)
149 {
150 struct lttng_kernel_session *session;
151 struct lttng_kernel_session_private *session_priv;
152 struct lttng_metadata_cache *metadata_cache;
153 int i;
154
155 mutex_lock(&sessions_mutex);
156 session = lttng_kvzalloc(sizeof(*session), GFP_KERNEL);
157 if (!session)
158 goto err;
159 session_priv = lttng_kvzalloc(sizeof(*session_priv), GFP_KERNEL);
160 if (!session_priv)
161 goto err_free_session;
162 session->priv = session_priv;
163 session_priv->pub = session;
164
165 INIT_LIST_HEAD(&session_priv->chan);
166 INIT_LIST_HEAD(&session_priv->events);
167 lttng_guid_gen(&session_priv->uuid);
168
169 metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache),
170 GFP_KERNEL);
171 if (!metadata_cache)
172 goto err_free_session_private;
173 metadata_cache->data = vzalloc(METADATA_CACHE_DEFAULT_SIZE);
174 if (!metadata_cache->data)
175 goto err_free_cache;
176 metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE;
177 kref_init(&metadata_cache->refcount);
178 mutex_init(&metadata_cache->lock);
179 session_priv->metadata_cache = metadata_cache;
180 INIT_LIST_HEAD(&metadata_cache->metadata_stream);
181 memcpy(&metadata_cache->uuid, &session_priv->uuid,
182 sizeof(metadata_cache->uuid));
183 INIT_LIST_HEAD(&session_priv->enablers_head);
184 for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
185 INIT_HLIST_HEAD(&session_priv->events_ht.table[i]);
186 list_add(&session_priv->list, &sessions);
187
188 if (lttng_id_tracker_init(&session->pid_tracker, session, TRACKER_PID))
189 goto tracker_alloc_error;
190 if (lttng_id_tracker_init(&session->vpid_tracker, session, TRACKER_VPID))
191 goto tracker_alloc_error;
192 if (lttng_id_tracker_init(&session->uid_tracker, session, TRACKER_UID))
193 goto tracker_alloc_error;
194 if (lttng_id_tracker_init(&session->vuid_tracker, session, TRACKER_VUID))
195 goto tracker_alloc_error;
196 if (lttng_id_tracker_init(&session->gid_tracker, session, TRACKER_GID))
197 goto tracker_alloc_error;
198 if (lttng_id_tracker_init(&session->vgid_tracker, session, TRACKER_VGID))
199 goto tracker_alloc_error;
200
201 mutex_unlock(&sessions_mutex);
202
203 return session;
204
205 tracker_alloc_error:
206 lttng_id_tracker_fini(&session->pid_tracker);
207 lttng_id_tracker_fini(&session->vpid_tracker);
208 lttng_id_tracker_fini(&session->uid_tracker);
209 lttng_id_tracker_fini(&session->vuid_tracker);
210 lttng_id_tracker_fini(&session->gid_tracker);
211 lttng_id_tracker_fini(&session->vgid_tracker);
212 err_free_cache:
213 kfree(metadata_cache);
214 err_free_session_private:
215 lttng_kvfree(session_priv);
216 err_free_session:
217 lttng_kvfree(session);
218 err:
219 mutex_unlock(&sessions_mutex);
220 return NULL;
221 }
222
223 static
224 struct lttng_counter_transport *lttng_counter_transport_find(const char *name)
225 {
226 struct lttng_counter_transport *transport;
227
228 list_for_each_entry(transport, &lttng_counter_transport_list, node) {
229 if (!strcmp(transport->name, name))
230 return transport;
231 }
232 return NULL;
233 }
234
235 struct lttng_counter *lttng_kernel_counter_create(
236 const char *counter_transport_name,
237 size_t number_dimensions, const size_t *dimensions_sizes)
238 {
239 struct lttng_counter *counter = NULL;
240 struct lttng_counter_transport *counter_transport = NULL;
241
242 counter_transport = lttng_counter_transport_find(counter_transport_name);
243 if (!counter_transport) {
244 printk(KERN_WARNING "LTTng: counter transport %s not found.\n",
245 counter_transport_name);
246 goto notransport;
247 }
248 if (!try_module_get(counter_transport->owner)) {
249 printk(KERN_WARNING "LTTng: Can't lock counter transport module.\n");
250 goto notransport;
251 }
252
253 counter = lttng_kvzalloc(sizeof(struct lttng_counter), GFP_KERNEL);
254 if (!counter)
255 goto nomem;
256
257 /* Create event notifier error counter. */
258 counter->ops = &counter_transport->ops;
259 counter->transport = counter_transport;
260
261 counter->counter = counter->ops->counter_create(
262 number_dimensions, dimensions_sizes, 0);
263 if (!counter->counter) {
264 goto create_error;
265 }
266
267 return counter;
268
269 create_error:
270 lttng_kvfree(counter);
271 nomem:
272 if (counter_transport)
273 module_put(counter_transport->owner);
274 notransport:
275 return NULL;
276 }
277
278 struct lttng_event_notifier_group *lttng_event_notifier_group_create(void)
279 {
280 struct lttng_transport *transport = NULL;
281 struct lttng_event_notifier_group *event_notifier_group;
282 const char *transport_name = "relay-event-notifier";
283 size_t subbuf_size = 4096; //TODO
284 size_t num_subbuf = 16; //TODO
285 unsigned int switch_timer_interval = 0;
286 unsigned int read_timer_interval = 0;
287 int i;
288
289 mutex_lock(&sessions_mutex);
290
291 transport = lttng_transport_find(transport_name);
292 if (!transport) {
293 printk(KERN_WARNING "LTTng: transport %s not found\n",
294 transport_name);
295 goto notransport;
296 }
297 if (!try_module_get(transport->owner)) {
298 printk(KERN_WARNING "LTTng: Can't lock transport %s module.\n",
299 transport_name);
300 goto notransport;
301 }
302
303 event_notifier_group = lttng_kvzalloc(sizeof(struct lttng_event_notifier_group),
304 GFP_KERNEL);
305 if (!event_notifier_group)
306 goto nomem;
307
308 /*
309 * Initialize the ring buffer used to store event notifier
310 * notifications.
311 */
312 event_notifier_group->ops = &transport->ops;
313 event_notifier_group->chan = transport->ops.priv->channel_create(
314 transport_name, event_notifier_group, NULL,
315 subbuf_size, num_subbuf, switch_timer_interval,
316 read_timer_interval);
317 if (!event_notifier_group->chan)
318 goto create_error;
319
320 event_notifier_group->transport = transport;
321
322 INIT_LIST_HEAD(&event_notifier_group->enablers_head);
323 INIT_LIST_HEAD(&event_notifier_group->event_notifiers_head);
324 for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
325 INIT_HLIST_HEAD(&event_notifier_group->events_ht.table[i]);
326
327 list_add(&event_notifier_group->node, &event_notifier_groups);
328
329 mutex_unlock(&sessions_mutex);
330
331 return event_notifier_group;
332
333 create_error:
334 lttng_kvfree(event_notifier_group);
335 nomem:
336 if (transport)
337 module_put(transport->owner);
338 notransport:
339 mutex_unlock(&sessions_mutex);
340 return NULL;
341 }
342
343 void metadata_cache_destroy(struct kref *kref)
344 {
345 struct lttng_metadata_cache *cache =
346 container_of(kref, struct lttng_metadata_cache, refcount);
347 vfree(cache->data);
348 kfree(cache);
349 }
350
351 void lttng_session_destroy(struct lttng_kernel_session *session)
352 {
353 struct lttng_kernel_channel_buffer_private *chan_priv, *tmpchan_priv;
354 struct lttng_kernel_event_recorder_private *event_recorder_priv, *tmpevent_recorder_priv;
355 struct lttng_metadata_stream *metadata_stream;
356 struct lttng_event_recorder_enabler *event_recorder_enabler, *tmp_event_recorder_enabler;
357 int ret;
358
359 mutex_lock(&sessions_mutex);
360 WRITE_ONCE(session->active, 0);
361 list_for_each_entry(chan_priv, &session->priv->chan, node) {
362 ret = lttng_syscalls_unregister_syscall_table(&chan_priv->parent.syscall_table);
363 WARN_ON(ret);
364 }
365 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
366 ret = _lttng_event_unregister(&event_recorder_priv->pub->parent);
367 WARN_ON(ret);
368 }
369 synchronize_trace(); /* Wait for in-flight events to complete */
370 list_for_each_entry(chan_priv, &session->priv->chan, node) {
371 ret = lttng_syscalls_destroy_syscall_table(&chan_priv->parent.syscall_table);
372 WARN_ON(ret);
373 }
374 list_for_each_entry_safe(event_recorder_enabler, tmp_event_recorder_enabler,
375 &session->priv->enablers_head, node)
376 lttng_event_enabler_destroy(&event_recorder_enabler->parent);
377 list_for_each_entry_safe(event_recorder_priv, tmpevent_recorder_priv, &session->priv->events, 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_notifier_enabler *event_notifier_enabler, *tmp_event_notifier_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, node) {
417 ret = _lttng_event_unregister(&event_notifier_priv->pub->parent);
418 WARN_ON(ret);
419 }
420
421 /* Wait for in-flight event notifier to complete */
422 synchronize_trace();
423
424 irq_work_sync(&event_notifier_group->wakeup_pending);
425
426 ret = lttng_syscalls_destroy_syscall_table(&event_notifier_group->syscall_table);
427 WARN_ON(ret);
428
429 list_for_each_entry_safe(event_notifier_enabler, tmp_event_notifier_enabler,
430 &event_notifier_group->enablers_head, node)
431 lttng_event_enabler_destroy(&event_notifier_enabler->parent);
432
433 list_for_each_entry_safe(event_notifier_priv, tmpevent_notifier_priv,
434 &event_notifier_group->event_notifiers_head, node)
435 _lttng_event_destroy(&event_notifier_priv->pub->parent);
436
437 if (event_notifier_group->error_counter) {
438 struct lttng_counter *error_counter = event_notifier_group->error_counter;
439
440 error_counter->ops->counter_destroy(error_counter->counter);
441 module_put(error_counter->transport->owner);
442 lttng_kvfree(error_counter);
443 event_notifier_group->error_counter = NULL;
444 }
445
446 event_notifier_group->ops->priv->channel_destroy(event_notifier_group->chan);
447 module_put(event_notifier_group->transport->owner);
448 list_del(&event_notifier_group->node);
449
450 mutex_unlock(&sessions_mutex);
451 lttng_kvfree(event_notifier_group);
452 }
453
454 int lttng_session_statedump(struct lttng_kernel_session *session)
455 {
456 int ret;
457
458 mutex_lock(&sessions_mutex);
459 ret = lttng_statedump_start(session);
460 mutex_unlock(&sessions_mutex);
461 return ret;
462 }
463
464 int lttng_session_enable(struct lttng_kernel_session *session)
465 {
466 int ret = 0;
467 struct lttng_kernel_channel_buffer_private *chan_priv;
468
469 mutex_lock(&sessions_mutex);
470 if (session->active) {
471 ret = -EBUSY;
472 goto end;
473 }
474
475 /* Set transient enabler state to "enabled" */
476 session->priv->tstate = 1;
477
478 /* We need to sync enablers with session before activation. */
479 lttng_session_sync_event_enablers(session);
480
481 /*
482 * Snapshot the number of events per channel to know the type of header
483 * we need to use.
484 */
485 list_for_each_entry(chan_priv, &session->priv->chan, node) {
486 if (chan_priv->header_type)
487 continue; /* don't change it if session stop/restart */
488 if (chan_priv->free_event_id < 31)
489 chan_priv->header_type = 1; /* compact */
490 else
491 chan_priv->header_type = 2; /* large */
492 }
493
494 /* Clear each stream's quiescent state. */
495 list_for_each_entry(chan_priv, &session->priv->chan, node) {
496 if (chan_priv->channel_type != METADATA_CHANNEL)
497 lib_ring_buffer_clear_quiescent_channel(chan_priv->rb_chan);
498 }
499
500 WRITE_ONCE(session->active, 1);
501 WRITE_ONCE(session->priv->been_active, 1);
502 ret = _lttng_session_metadata_statedump(session);
503 if (ret) {
504 WRITE_ONCE(session->active, 0);
505 goto end;
506 }
507 ret = lttng_statedump_start(session);
508 if (ret)
509 WRITE_ONCE(session->active, 0);
510 end:
511 mutex_unlock(&sessions_mutex);
512 return ret;
513 }
514
515 int lttng_session_disable(struct lttng_kernel_session *session)
516 {
517 int ret = 0;
518 struct lttng_kernel_channel_buffer_private *chan_priv;
519
520 mutex_lock(&sessions_mutex);
521 if (!session->active) {
522 ret = -EBUSY;
523 goto end;
524 }
525 WRITE_ONCE(session->active, 0);
526
527 /* Set transient enabler state to "disabled" */
528 session->priv->tstate = 0;
529 lttng_session_sync_event_enablers(session);
530
531 /* Set each stream's quiescent state. */
532 list_for_each_entry(chan_priv, &session->priv->chan, node) {
533 if (chan_priv->channel_type != METADATA_CHANNEL)
534 lib_ring_buffer_set_quiescent_channel(chan_priv->rb_chan);
535 }
536 end:
537 mutex_unlock(&sessions_mutex);
538 return ret;
539 }
540
541 int lttng_session_metadata_regenerate(struct lttng_kernel_session *session)
542 {
543 int ret = 0;
544 struct lttng_kernel_channel_buffer_private *chan_priv;
545 struct lttng_kernel_event_recorder_private *event_recorder_priv;
546 struct lttng_metadata_cache *cache = session->priv->metadata_cache;
547 struct lttng_metadata_stream *stream;
548
549 mutex_lock(&sessions_mutex);
550 if (!session->active) {
551 ret = -EBUSY;
552 goto end;
553 }
554
555 mutex_lock(&cache->lock);
556 memset(cache->data, 0, cache->cache_alloc);
557 cache->metadata_written = 0;
558 cache->version++;
559 list_for_each_entry(stream, &session->priv->metadata_cache->metadata_stream, list) {
560 stream->metadata_out = 0;
561 stream->metadata_in = 0;
562 }
563 mutex_unlock(&cache->lock);
564
565 session->priv->metadata_dumped = 0;
566 list_for_each_entry(chan_priv, &session->priv->chan, node) {
567 chan_priv->metadata_dumped = 0;
568 }
569
570 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
571 event_recorder_priv->metadata_dumped = 0;
572 }
573
574 ret = _lttng_session_metadata_statedump(session);
575
576 end:
577 mutex_unlock(&sessions_mutex);
578 return ret;
579 }
580
581 static
582 bool is_channel_buffer_metadata(struct lttng_kernel_channel_common *channel)
583 {
584 struct lttng_kernel_channel_buffer *chan_buf;
585
586 if (channel->type != LTTNG_KERNEL_CHANNEL_TYPE_BUFFER)
587 return false;
588 chan_buf = container_of(channel, struct lttng_kernel_channel_buffer, parent);
589 if (chan_buf->priv->channel_type == METADATA_CHANNEL)
590 return true;
591 return false;
592 }
593
594 int lttng_channel_enable(struct lttng_kernel_channel_common *channel)
595 {
596 int ret = 0;
597
598 mutex_lock(&sessions_mutex);
599 if (is_channel_buffer_metadata(channel)) {
600 ret = -EPERM;
601 goto end;
602 }
603 if (channel->enabled) {
604 ret = -EEXIST;
605 goto end;
606 }
607 /* Set transient enabler state to "enabled" */
608 channel->priv->tstate = 1;
609 lttng_session_sync_event_enablers(channel->session);
610 /* Set atomically the state to "enabled" */
611 WRITE_ONCE(channel->enabled, 1);
612 end:
613 mutex_unlock(&sessions_mutex);
614 return ret;
615 }
616
617 int lttng_channel_disable(struct lttng_kernel_channel_common *channel)
618 {
619 int ret = 0;
620
621 mutex_lock(&sessions_mutex);
622 if (is_channel_buffer_metadata(channel)) {
623 ret = -EPERM;
624 goto end;
625 }
626 if (!channel->enabled) {
627 ret = -EEXIST;
628 goto end;
629 }
630 /* Set atomically the state to "disabled" */
631 WRITE_ONCE(channel->enabled, 0);
632 /* Set transient enabler state to "enabled" */
633 channel->priv->tstate = 0;
634 lttng_session_sync_event_enablers(channel->session);
635 end:
636 mutex_unlock(&sessions_mutex);
637 return ret;
638 }
639
640 int lttng_event_enable(struct lttng_kernel_event_common *event)
641 {
642 int ret = 0;
643
644 mutex_lock(&sessions_mutex);
645 switch (event->type) {
646 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
647 {
648 struct lttng_kernel_event_recorder *event_recorder =
649 container_of(event, struct lttng_kernel_event_recorder, parent);
650
651 if (event_recorder->chan->priv->channel_type == METADATA_CHANNEL) {
652 ret = -EPERM;
653 goto end;
654 }
655 break;
656 }
657 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
658 switch (event->priv->instrumentation) {
659 case LTTNG_KERNEL_ABI_KRETPROBE:
660 ret = -EINVAL;
661 goto end;
662 default:
663 break;
664 }
665 break;
666 default:
667 break;
668 }
669
670 if (event->enabled) {
671 ret = -EEXIST;
672 goto end;
673 }
674 switch (event->priv->instrumentation) {
675 case LTTNG_KERNEL_ABI_TRACEPOINT:
676 lttng_fallthrough;
677 case LTTNG_KERNEL_ABI_SYSCALL:
678 ret = -EINVAL;
679 break;
680
681 case LTTNG_KERNEL_ABI_KPROBE:
682 lttng_fallthrough;
683 case LTTNG_KERNEL_ABI_UPROBE:
684 WRITE_ONCE(event->enabled, 1);
685 break;
686
687 case LTTNG_KERNEL_ABI_KRETPROBE:
688 ret = lttng_kretprobes_event_enable_state(event, 1);
689 break;
690
691 case LTTNG_KERNEL_ABI_FUNCTION:
692 lttng_fallthrough;
693 case LTTNG_KERNEL_ABI_NOOP:
694 lttng_fallthrough;
695 default:
696 WARN_ON_ONCE(1);
697 ret = -EINVAL;
698 }
699 end:
700 mutex_unlock(&sessions_mutex);
701 return ret;
702 }
703
704 int lttng_event_disable(struct lttng_kernel_event_common *event)
705 {
706 int ret = 0;
707
708 mutex_lock(&sessions_mutex);
709 switch (event->type) {
710 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
711 {
712 struct lttng_kernel_event_recorder *event_recorder =
713 container_of(event, struct lttng_kernel_event_recorder, parent);
714
715 if (event_recorder->chan->priv->channel_type == METADATA_CHANNEL) {
716 ret = -EPERM;
717 goto end;
718 }
719 break;
720 }
721 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
722 switch (event->priv->instrumentation) {
723 case LTTNG_KERNEL_ABI_KRETPROBE:
724 ret = -EINVAL;
725 goto end;
726 default:
727 break;
728 }
729 break;
730 default:
731 break;
732 }
733
734 if (!event->enabled) {
735 ret = -EEXIST;
736 goto end;
737 }
738 switch (event->priv->instrumentation) {
739 case LTTNG_KERNEL_ABI_TRACEPOINT:
740 lttng_fallthrough;
741 case LTTNG_KERNEL_ABI_SYSCALL:
742 ret = -EINVAL;
743 break;
744
745 case LTTNG_KERNEL_ABI_KPROBE:
746 lttng_fallthrough;
747 case LTTNG_KERNEL_ABI_UPROBE:
748 WRITE_ONCE(event->enabled, 0);
749 break;
750
751 case LTTNG_KERNEL_ABI_KRETPROBE:
752 ret = lttng_kretprobes_event_enable_state(event, 0);
753 break;
754
755 case LTTNG_KERNEL_ABI_FUNCTION:
756 lttng_fallthrough;
757 case LTTNG_KERNEL_ABI_NOOP:
758 lttng_fallthrough;
759 default:
760 WARN_ON_ONCE(1);
761 ret = -EINVAL;
762 }
763 end:
764 mutex_unlock(&sessions_mutex);
765 return ret;
766 }
767
768 struct lttng_kernel_channel_buffer *lttng_channel_buffer_create(struct lttng_kernel_session *session,
769 const char *transport_name,
770 void *buf_addr,
771 size_t subbuf_size, size_t num_subbuf,
772 unsigned int switch_timer_interval,
773 unsigned int read_timer_interval,
774 enum channel_type channel_type)
775 {
776 struct lttng_kernel_channel_buffer *chan;
777 struct lttng_kernel_channel_buffer_private *chan_priv;
778 struct lttng_transport *transport = NULL;
779
780 mutex_lock(&sessions_mutex);
781 if (session->priv->been_active && channel_type != METADATA_CHANNEL)
782 goto active; /* Refuse to add channel to active session */
783 transport = lttng_transport_find(transport_name);
784 if (!transport) {
785 printk(KERN_WARNING "LTTng: transport %s not found\n",
786 transport_name);
787 goto notransport;
788 }
789 if (!try_module_get(transport->owner)) {
790 printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
791 goto notransport;
792 }
793 chan = kzalloc(sizeof(struct lttng_kernel_channel_buffer), GFP_KERNEL);
794 if (!chan)
795 goto nomem;
796 chan_priv = kzalloc(sizeof(struct lttng_kernel_channel_buffer_private), GFP_KERNEL);
797 if (!chan_priv)
798 goto nomem_priv;
799 chan->priv = chan_priv;
800 chan_priv->pub = chan;
801 chan->parent.type = LTTNG_KERNEL_CHANNEL_TYPE_BUFFER;
802 chan->parent.session = session;
803 chan->priv->id = session->priv->free_chan_id++;
804 chan->ops = &transport->ops;
805 /*
806 * Note: the channel creation op already writes into the packet
807 * headers. Therefore the "chan" information used as input
808 * should be already accessible.
809 */
810 chan->priv->rb_chan = transport->ops.priv->channel_create(transport_name,
811 chan, buf_addr, subbuf_size, num_subbuf,
812 switch_timer_interval, read_timer_interval);
813 if (!chan->priv->rb_chan)
814 goto create_error;
815 chan->priv->parent.tstate = 1;
816 chan->parent.enabled = 1;
817 chan->priv->transport = transport;
818 chan->priv->channel_type = channel_type;
819 list_add(&chan->priv->node, &session->priv->chan);
820 mutex_unlock(&sessions_mutex);
821 return chan;
822
823 create_error:
824 kfree(chan_priv);
825 nomem_priv:
826 kfree(chan);
827 nomem:
828 if (transport)
829 module_put(transport->owner);
830 notransport:
831 active:
832 mutex_unlock(&sessions_mutex);
833 return NULL;
834 }
835
836 /*
837 * Only used internally at session destruction for per-cpu channels, and
838 * when metadata channel is released.
839 * Needs to be called with sessions mutex held.
840 */
841 static
842 void _lttng_channel_destroy(struct lttng_kernel_channel_buffer *chan)
843 {
844 chan->ops->priv->channel_destroy(chan->priv->rb_chan);
845 module_put(chan->priv->transport->owner);
846 list_del(&chan->priv->node);
847 lttng_kernel_destroy_context(chan->priv->ctx);
848 kfree(chan->priv);
849 kfree(chan);
850 }
851
852 void lttng_metadata_channel_destroy(struct lttng_kernel_channel_buffer *chan)
853 {
854 BUG_ON(chan->priv->channel_type != METADATA_CHANNEL);
855
856 /* Protect the metadata cache with the sessions_mutex. */
857 mutex_lock(&sessions_mutex);
858 _lttng_channel_destroy(chan);
859 mutex_unlock(&sessions_mutex);
860 }
861 EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy);
862
863 static
864 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream)
865 {
866 stream->finalized = 1;
867 wake_up_interruptible(&stream->read_wait);
868 }
869
870
871 /*
872 * Supports event creation while tracing session is active.
873 * Needs to be called with sessions mutex held.
874 */
875 struct lttng_kernel_event_recorder *_lttng_kernel_event_recorder_create(struct lttng_event_recorder_enabler *event_enabler,
876 const struct lttng_kernel_event_desc *event_desc)
877 {
878 struct lttng_kernel_channel_buffer *chan = event_enabler->chan;
879 struct lttng_kernel_abi_event *event_param = &event_enabler->parent.event_param;
880 enum lttng_kernel_abi_instrumentation itype = event_param->instrumentation;
881 struct lttng_kernel_session *session = chan->parent.session;
882 struct lttng_kernel_event_recorder *event_recorder;
883 struct lttng_kernel_event_recorder_private *event_recorder_priv;
884 const char *event_name;
885 struct hlist_head *head;
886 int ret;
887
888 if (chan->priv->free_event_id == -1U) {
889 ret = -EMFILE;
890 goto full;
891 }
892
893 switch (itype) {
894 case LTTNG_KERNEL_ABI_TRACEPOINT:
895 event_name = event_desc->event_name;
896 break;
897
898 case LTTNG_KERNEL_ABI_KPROBE:
899 lttng_fallthrough;
900 case LTTNG_KERNEL_ABI_UPROBE:
901 lttng_fallthrough;
902 case LTTNG_KERNEL_ABI_KRETPROBE:
903 lttng_fallthrough;
904 case LTTNG_KERNEL_ABI_SYSCALL:
905 event_name = event_param->name;
906 break;
907
908 case LTTNG_KERNEL_ABI_FUNCTION:
909 lttng_fallthrough;
910 case LTTNG_KERNEL_ABI_NOOP:
911 lttng_fallthrough;
912 default:
913 WARN_ON_ONCE(1);
914 ret = -EINVAL;
915 goto type_error;
916 }
917
918 head = utils_borrow_hash_table_bucket(session->priv->events_ht.table,
919 LTTNG_EVENT_HT_SIZE, event_name);
920 lttng_hlist_for_each_entry(event_recorder_priv, head, hlist) {
921 WARN_ON_ONCE(!event_recorder_priv->parent.desc);
922 if (!strncmp(event_recorder_priv->parent.desc->event_name, event_name,
923 LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1)
924 && chan == event_recorder_priv->pub->chan) {
925 ret = -EEXIST;
926 goto exist;
927 }
928 }
929
930 event_recorder = kmem_cache_zalloc(event_recorder_cache, GFP_KERNEL);
931 if (!event_recorder) {
932 ret = -ENOMEM;
933 goto cache_error;
934 }
935 event_recorder_priv = kmem_cache_zalloc(event_recorder_private_cache, GFP_KERNEL);
936 if (!event_recorder_priv) {
937 ret = -ENOMEM;
938 goto cache_private_error;
939 }
940 event_recorder_priv->pub = event_recorder;
941 event_recorder_priv->parent.pub = &event_recorder->parent;
942 event_recorder->priv = event_recorder_priv;
943 event_recorder->parent.priv = &event_recorder_priv->parent;
944 event_recorder->parent.type = LTTNG_KERNEL_EVENT_TYPE_RECORDER;
945
946 event_recorder->parent.run_filter = lttng_kernel_interpret_event_filter;
947 event_recorder->chan = chan;
948 event_recorder->priv->id = chan->priv->free_event_id++;
949 event_recorder->priv->parent.instrumentation = itype;
950 INIT_LIST_HEAD(&event_recorder->priv->parent.filter_bytecode_runtime_head);
951 INIT_LIST_HEAD(&event_recorder->priv->parent.enablers_ref_head);
952
953 switch (itype) {
954 case LTTNG_KERNEL_ABI_TRACEPOINT:
955 /* Event will be enabled by enabler sync. */
956 event_recorder->parent.enabled = 0;
957 event_recorder->priv->parent.registered = 0;
958 event_recorder->priv->parent.desc = lttng_event_desc_get(event_name);
959 if (!event_recorder->priv->parent.desc) {
960 ret = -ENOENT;
961 goto register_error;
962 }
963 /* Populate lttng_event structure before event registration. */
964 smp_wmb();
965 break;
966
967 case LTTNG_KERNEL_ABI_KPROBE:
968 /*
969 * Needs to be explicitly enabled after creation, since
970 * we may want to apply filters.
971 */
972 event_recorder->parent.enabled = 0;
973 event_recorder->priv->parent.registered = 1;
974 /*
975 * Populate lttng_event structure before event
976 * registration.
977 */
978 smp_wmb();
979 ret = lttng_kprobes_register_event(event_name,
980 event_param->u.kprobe.symbol_name,
981 event_param->u.kprobe.offset,
982 event_param->u.kprobe.addr,
983 &event_recorder->parent);
984 if (ret) {
985 ret = -EINVAL;
986 goto register_error;
987 }
988 ret = try_module_get(event_recorder->priv->parent.desc->owner);
989 WARN_ON_ONCE(!ret);
990 break;
991
992 case LTTNG_KERNEL_ABI_KRETPROBE:
993 {
994 struct lttng_kernel_event_recorder *event_recorder_return;
995 struct lttng_kernel_event_recorder_private *event_recorder_return_priv;
996
997 /* kretprobe defines 2 events */
998 /*
999 * Needs to be explicitly enabled after creation, since
1000 * we may want to apply filters.
1001 */
1002 event_recorder->parent.enabled = 0;
1003 event_recorder->priv->parent.registered = 1;
1004
1005 event_recorder_return = kmem_cache_zalloc(event_recorder_cache, GFP_KERNEL);
1006 if (!event_recorder_return) {
1007 ret = -ENOMEM;
1008 goto register_error;
1009 }
1010 event_recorder_return_priv = kmem_cache_zalloc(event_recorder_private_cache, GFP_KERNEL);
1011 if (!event_recorder_return_priv) {
1012 kmem_cache_free(event_recorder_cache, event_recorder_return);
1013 ret = -ENOMEM;
1014 goto register_error;
1015 }
1016 event_recorder_return_priv->pub = event_recorder_return;
1017 event_recorder_return_priv->parent.pub = &event_recorder_return->parent;
1018 event_recorder_return->priv = event_recorder_return_priv;
1019 event_recorder_return->parent.priv = &event_recorder_return_priv->parent;
1020 event_recorder_return->parent.type = LTTNG_KERNEL_EVENT_TYPE_RECORDER;
1021
1022 event_recorder_return->parent.run_filter = lttng_kernel_interpret_event_filter;
1023 event_recorder_return->chan = chan;
1024 event_recorder_return->priv->id = chan->priv->free_event_id++;
1025 event_recorder_return->priv->parent.instrumentation = itype;
1026 event_recorder_return->parent.enabled = 0;
1027 event_recorder_return->priv->parent.registered = 1;
1028 INIT_LIST_HEAD(&event_recorder_return->priv->parent.filter_bytecode_runtime_head);
1029 INIT_LIST_HEAD(&event_recorder_return->priv->parent.enablers_ref_head);
1030 /*
1031 * Populate lttng_event structure before kretprobe registration.
1032 */
1033 smp_wmb();
1034 ret = lttng_kretprobes_register(event_name,
1035 event_param->u.kretprobe.symbol_name,
1036 event_param->u.kretprobe.offset,
1037 event_param->u.kretprobe.addr,
1038 &event_recorder->parent, &event_recorder_return->parent);
1039 if (ret) {
1040 kmem_cache_free(event_recorder_private_cache, event_recorder_return_priv);
1041 kmem_cache_free(event_recorder_cache, event_recorder_return);
1042 ret = -EINVAL;
1043 goto register_error;
1044 }
1045 /* Take 2 refs on the module: one per event. */
1046 ret = try_module_get(event_recorder->priv->parent.desc->owner);
1047 WARN_ON_ONCE(!ret);
1048 ret = try_module_get(event_recorder_return->priv->parent.desc->owner);
1049 WARN_ON_ONCE(!ret);
1050 ret = _lttng_event_metadata_statedump(chan->parent.session, chan,
1051 event_recorder_return);
1052 WARN_ON_ONCE(ret > 0);
1053 if (ret) {
1054 kmem_cache_free(event_recorder_private_cache, event_recorder_return_priv);
1055 kmem_cache_free(event_recorder_cache, event_recorder_return);
1056 module_put(event_recorder_return->priv->parent.desc->owner);
1057 module_put(event_recorder->priv->parent.desc->owner);
1058 goto statedump_error;
1059 }
1060 list_add(&event_recorder_return->priv->node, &chan->parent.session->priv->events);
1061 break;
1062 }
1063
1064 case LTTNG_KERNEL_ABI_SYSCALL:
1065 /*
1066 * Needs to be explicitly enabled after creation, since
1067 * we may want to apply filters.
1068 */
1069 event_recorder->parent.enabled = 0;
1070 event_recorder->priv->parent.registered = 0;
1071 event_recorder->priv->parent.desc = event_desc;
1072 switch (event_param->u.syscall.entryexit) {
1073 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
1074 ret = -EINVAL;
1075 goto register_error;
1076 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
1077 event_recorder->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_ENTRY;
1078 break;
1079 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
1080 event_recorder->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_EXIT;
1081 break;
1082 }
1083 switch (event_param->u.syscall.abi) {
1084 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
1085 ret = -EINVAL;
1086 goto register_error;
1087 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
1088 event_recorder->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE;
1089 break;
1090 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
1091 event_recorder->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT;
1092 break;
1093 }
1094 if (!event_recorder->priv->parent.desc) {
1095 ret = -EINVAL;
1096 goto register_error;
1097 }
1098 break;
1099
1100 case LTTNG_KERNEL_ABI_UPROBE:
1101 /*
1102 * Needs to be explicitly enabled after creation, since
1103 * we may want to apply filters.
1104 */
1105 event_recorder->parent.enabled = 0;
1106 event_recorder->priv->parent.registered = 1;
1107
1108 /*
1109 * Populate lttng_event structure before event
1110 * registration.
1111 */
1112 smp_wmb();
1113
1114 ret = lttng_uprobes_register_event(event_param->name,
1115 event_param->u.uprobe.fd,
1116 &event_recorder->parent);
1117 if (ret)
1118 goto register_error;
1119 ret = try_module_get(event_recorder->priv->parent.desc->owner);
1120 WARN_ON_ONCE(!ret);
1121 break;
1122
1123 case LTTNG_KERNEL_ABI_FUNCTION:
1124 lttng_fallthrough;
1125 case LTTNG_KERNEL_ABI_NOOP:
1126 lttng_fallthrough;
1127 default:
1128 WARN_ON_ONCE(1);
1129 ret = -EINVAL;
1130 goto register_error;
1131 }
1132 ret = _lttng_event_metadata_statedump(chan->parent.session, chan, event_recorder);
1133 WARN_ON_ONCE(ret > 0);
1134 if (ret) {
1135 goto statedump_error;
1136 }
1137 hlist_add_head(&event_recorder->priv->hlist, head);
1138 list_add(&event_recorder->priv->node, &chan->parent.session->priv->events);
1139 return event_recorder;
1140
1141 statedump_error:
1142 /* If a statedump error occurs, events will not be readable. */
1143 register_error:
1144 kmem_cache_free(event_recorder_private_cache, event_recorder_priv);
1145 cache_private_error:
1146 kmem_cache_free(event_recorder_cache, event_recorder);
1147 cache_error:
1148 exist:
1149 type_error:
1150 full:
1151 return ERR_PTR(ret);
1152 }
1153
1154 struct lttng_kernel_event_notifier *_lttng_event_notifier_create(struct lttng_event_notifier_enabler *event_enabler,
1155 const struct lttng_kernel_event_desc *event_desc)
1156 {
1157 struct lttng_event_notifier_group *event_notifier_group = event_enabler->group;
1158 struct lttng_kernel_abi_event *event_param = &event_enabler->parent.event_param;
1159 uint64_t token = event_enabler->parent.user_token;
1160 enum lttng_kernel_abi_instrumentation itype = event_param->instrumentation;
1161 struct lttng_kernel_event_notifier *event_notifier;
1162 struct lttng_kernel_event_notifier_private *event_notifier_priv;
1163 struct lttng_counter *error_counter;
1164 const char *event_name;
1165 struct hlist_head *head;
1166 int ret;
1167
1168 switch (itype) {
1169 case LTTNG_KERNEL_ABI_TRACEPOINT:
1170 event_name = event_desc->event_name;
1171 break;
1172
1173 case LTTNG_KERNEL_ABI_KPROBE:
1174 lttng_fallthrough;
1175 case LTTNG_KERNEL_ABI_UPROBE:
1176 lttng_fallthrough;
1177 case LTTNG_KERNEL_ABI_SYSCALL:
1178 event_name = event_param->name;
1179 break;
1180
1181 case LTTNG_KERNEL_ABI_KRETPROBE:
1182 lttng_fallthrough;
1183 case LTTNG_KERNEL_ABI_FUNCTION:
1184 lttng_fallthrough;
1185 case LTTNG_KERNEL_ABI_NOOP:
1186 lttng_fallthrough;
1187 default:
1188 WARN_ON_ONCE(1);
1189 ret = -EINVAL;
1190 goto type_error;
1191 }
1192
1193 head = utils_borrow_hash_table_bucket(event_notifier_group->events_ht.table,
1194 LTTNG_EVENT_HT_SIZE, event_name);
1195 lttng_hlist_for_each_entry(event_notifier_priv, head, hlist) {
1196 WARN_ON_ONCE(!event_notifier_priv->parent.desc);
1197 if (!strncmp(event_notifier_priv->parent.desc->event_name, event_name,
1198 LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1)
1199 && event_notifier_group == event_notifier_priv->group
1200 && token == event_notifier_priv->parent.user_token) {
1201 ret = -EEXIST;
1202 goto exist;
1203 }
1204 }
1205
1206 event_notifier = kmem_cache_zalloc(event_notifier_cache, GFP_KERNEL);
1207 if (!event_notifier) {
1208 ret = -ENOMEM;
1209 goto cache_error;
1210 }
1211 event_notifier_priv = kmem_cache_zalloc(event_notifier_private_cache, GFP_KERNEL);
1212 if (!event_notifier_priv) {
1213 ret = -ENOMEM;
1214 goto cache_private_error;
1215 }
1216 event_notifier_priv->pub = event_notifier;
1217 event_notifier_priv->parent.pub = &event_notifier->parent;
1218 event_notifier->priv = event_notifier_priv;
1219 event_notifier->parent.priv = &event_notifier_priv->parent;
1220 event_notifier->parent.type = LTTNG_KERNEL_EVENT_TYPE_NOTIFIER;
1221
1222 event_notifier->priv->group = event_notifier_group;
1223 event_notifier->priv->parent.user_token = event_enabler->parent.user_token;
1224 event_notifier->priv->error_counter_index = event_enabler->error_counter_index;
1225 event_notifier->priv->num_captures = 0;
1226 event_notifier->priv->parent.instrumentation = itype;
1227 event_notifier->notification_send = lttng_event_notifier_notification_send;
1228 INIT_LIST_HEAD(&event_notifier->priv->parent.filter_bytecode_runtime_head);
1229 INIT_LIST_HEAD(&event_notifier->priv->parent.enablers_ref_head);
1230 INIT_LIST_HEAD(&event_notifier->priv->capture_bytecode_runtime_head);
1231 event_notifier->parent.run_filter = lttng_kernel_interpret_event_filter;
1232
1233 switch (itype) {
1234 case LTTNG_KERNEL_ABI_TRACEPOINT:
1235 /* Event will be enabled by enabler sync. */
1236 event_notifier->parent.enabled = 0;
1237 event_notifier->priv->parent.registered = 0;
1238 event_notifier->priv->parent.desc = lttng_event_desc_get(event_name);
1239 if (!event_notifier->priv->parent.desc) {
1240 ret = -ENOENT;
1241 goto register_error;
1242 }
1243 /* Populate lttng_event_notifier structure before event registration. */
1244 smp_wmb();
1245 break;
1246
1247 case LTTNG_KERNEL_ABI_KPROBE:
1248 /*
1249 * Needs to be explicitly enabled after creation, since
1250 * we may want to apply filters.
1251 */
1252 event_notifier->parent.enabled = 0;
1253 event_notifier->priv->parent.registered = 1;
1254 /*
1255 * Populate lttng_event_notifier structure before event
1256 * registration.
1257 */
1258 smp_wmb();
1259 ret = lttng_kprobes_register_event(event_param->u.kprobe.symbol_name,
1260 event_param->u.kprobe.symbol_name,
1261 event_param->u.kprobe.offset,
1262 event_param->u.kprobe.addr,
1263 &event_notifier->parent);
1264 if (ret) {
1265 ret = -EINVAL;
1266 goto register_error;
1267 }
1268 ret = try_module_get(event_notifier->priv->parent.desc->owner);
1269 WARN_ON_ONCE(!ret);
1270 break;
1271
1272 case LTTNG_KERNEL_ABI_SYSCALL:
1273 /*
1274 * Needs to be explicitly enabled after creation, since
1275 * we may want to apply filters.
1276 */
1277 event_notifier->parent.enabled = 0;
1278 event_notifier->priv->parent.registered = 0;
1279 event_notifier->priv->parent.desc = event_desc;
1280 switch (event_param->u.syscall.entryexit) {
1281 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
1282 ret = -EINVAL;
1283 goto register_error;
1284 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
1285 event_notifier->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_ENTRY;
1286 break;
1287 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
1288 event_notifier->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_EXIT;
1289 break;
1290 }
1291 switch (event_param->u.syscall.abi) {
1292 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
1293 ret = -EINVAL;
1294 goto register_error;
1295 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
1296 event_notifier->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE;
1297 break;
1298 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
1299 event_notifier->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT;
1300 break;
1301 }
1302
1303 if (!event_notifier->priv->parent.desc) {
1304 ret = -EINVAL;
1305 goto register_error;
1306 }
1307 break;
1308
1309 case LTTNG_KERNEL_ABI_UPROBE:
1310 /*
1311 * Needs to be explicitly enabled after creation, since
1312 * we may want to apply filters.
1313 */
1314 event_notifier->parent.enabled = 0;
1315 event_notifier->priv->parent.registered = 1;
1316
1317 /*
1318 * Populate lttng_event_notifier structure before
1319 * event_notifier registration.
1320 */
1321 smp_wmb();
1322
1323 ret = lttng_uprobes_register_event(event_param->name,
1324 event_param->u.uprobe.fd,
1325 &event_notifier->parent);
1326 if (ret)
1327 goto register_error;
1328 ret = try_module_get(event_notifier->priv->parent.desc->owner);
1329 WARN_ON_ONCE(!ret);
1330 break;
1331
1332 case LTTNG_KERNEL_ABI_KRETPROBE:
1333 lttng_fallthrough;
1334 case LTTNG_KERNEL_ABI_FUNCTION:
1335 lttng_fallthrough;
1336 case LTTNG_KERNEL_ABI_NOOP:
1337 lttng_fallthrough;
1338 default:
1339 WARN_ON_ONCE(1);
1340 ret = -EINVAL;
1341 goto register_error;
1342 }
1343
1344 list_add(&event_notifier->priv->node, &event_notifier_group->event_notifiers_head);
1345 hlist_add_head(&event_notifier->priv->hlist, head);
1346
1347 /*
1348 * Clear the error counter bucket. The sessiond keeps track of which
1349 * bucket is currently in use. We trust it. The session lock
1350 * synchronizes against concurrent creation of the error
1351 * counter.
1352 */
1353 error_counter = event_notifier_group->error_counter;
1354 if (error_counter) {
1355 size_t dimension_index[1];
1356
1357 /*
1358 * Check that the index is within the boundary of the counter.
1359 */
1360 if (event_notifier->priv->error_counter_index >= event_notifier_group->error_counter_len) {
1361 printk(KERN_INFO "LTTng: event_notifier: Error counter index out-of-bound: counter-len=%zu, index=%llu\n",
1362 event_notifier_group->error_counter_len, event_notifier->priv->error_counter_index);
1363 ret = -EINVAL;
1364 goto register_error;
1365 }
1366
1367 dimension_index[0] = event_notifier->priv->error_counter_index;
1368 ret = error_counter->ops->counter_clear(error_counter->counter, dimension_index);
1369 if (ret) {
1370 printk(KERN_INFO "LTTng: event_notifier: Unable to clear error counter bucket %llu\n",
1371 event_notifier->priv->error_counter_index);
1372 goto register_error;
1373 }
1374 }
1375
1376 return event_notifier;
1377
1378 register_error:
1379 kmem_cache_free(event_notifier_private_cache, event_notifier_priv);
1380 cache_private_error:
1381 kmem_cache_free(event_notifier_cache, event_notifier);
1382 cache_error:
1383 exist:
1384 type_error:
1385 return ERR_PTR(ret);
1386 }
1387
1388 int lttng_kernel_counter_read(struct lttng_counter *counter,
1389 const size_t *dim_indexes, int32_t cpu,
1390 int64_t *val, bool *overflow, bool *underflow)
1391 {
1392 return counter->ops->counter_read(counter->counter, dim_indexes,
1393 cpu, val, overflow, underflow);
1394 }
1395
1396 int lttng_kernel_counter_aggregate(struct lttng_counter *counter,
1397 const size_t *dim_indexes, int64_t *val,
1398 bool *overflow, bool *underflow)
1399 {
1400 return counter->ops->counter_aggregate(counter->counter, dim_indexes,
1401 val, overflow, underflow);
1402 }
1403
1404 int lttng_kernel_counter_clear(struct lttng_counter *counter,
1405 const size_t *dim_indexes)
1406 {
1407 return counter->ops->counter_clear(counter->counter, dim_indexes);
1408 }
1409
1410 struct lttng_kernel_event_recorder *lttng_kernel_event_recorder_create(struct lttng_event_recorder_enabler *event_enabler,
1411 const struct lttng_kernel_event_desc *event_desc)
1412 {
1413 struct lttng_kernel_event_recorder *event;
1414
1415 mutex_lock(&sessions_mutex);
1416 event = _lttng_kernel_event_recorder_create(event_enabler, event_desc);
1417 mutex_unlock(&sessions_mutex);
1418 return event;
1419 }
1420
1421 struct lttng_kernel_event_notifier *lttng_event_notifier_create(struct lttng_event_notifier_enabler *event_enabler,
1422 const struct lttng_kernel_event_desc *event_desc)
1423 {
1424 struct lttng_kernel_event_notifier *event_notifier;
1425
1426 mutex_lock(&sessions_mutex);
1427 event_notifier = _lttng_event_notifier_create(event_enabler, event_desc);
1428 mutex_unlock(&sessions_mutex);
1429 return event_notifier;
1430 }
1431
1432 /* Only used for tracepoints for now. */
1433 static
1434 void register_event(struct lttng_kernel_event_common *event)
1435 {
1436 const struct lttng_kernel_event_desc *desc;
1437 int ret = -EINVAL;
1438
1439 if (event->priv->registered)
1440 return;
1441
1442 desc = event->priv->desc;
1443 switch (event->priv->instrumentation) {
1444 case LTTNG_KERNEL_ABI_TRACEPOINT:
1445 ret = lttng_wrapper_tracepoint_probe_register(desc->event_kname,
1446 desc->tp_class->probe_callback,
1447 event);
1448 break;
1449
1450 case LTTNG_KERNEL_ABI_SYSCALL:
1451 ret = lttng_syscall_filter_enable_event(event);
1452 break;
1453
1454 case LTTNG_KERNEL_ABI_KPROBE:
1455 lttng_fallthrough;
1456 case LTTNG_KERNEL_ABI_UPROBE:
1457 ret = 0;
1458 break;
1459
1460 case LTTNG_KERNEL_ABI_KRETPROBE:
1461 switch (event->type) {
1462 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1463 ret = 0;
1464 break;
1465 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1466 WARN_ON_ONCE(1);
1467 break;
1468 }
1469 break;
1470
1471 case LTTNG_KERNEL_ABI_FUNCTION:
1472 lttng_fallthrough;
1473 case LTTNG_KERNEL_ABI_NOOP:
1474 lttng_fallthrough;
1475 default:
1476 WARN_ON_ONCE(1);
1477 }
1478 if (!ret)
1479 event->priv->registered = 1;
1480 }
1481
1482 int _lttng_event_unregister(struct lttng_kernel_event_common *event)
1483 {
1484 struct lttng_kernel_event_common_private *event_priv = event->priv;
1485 const struct lttng_kernel_event_desc *desc;
1486 int ret = -EINVAL;
1487
1488 if (!event_priv->registered)
1489 return 0;
1490
1491 desc = event_priv->desc;
1492 switch (event_priv->instrumentation) {
1493 case LTTNG_KERNEL_ABI_TRACEPOINT:
1494 ret = lttng_wrapper_tracepoint_probe_unregister(event_priv->desc->event_kname,
1495 event_priv->desc->tp_class->probe_callback,
1496 event);
1497 break;
1498
1499 case LTTNG_KERNEL_ABI_KPROBE:
1500 lttng_kprobes_unregister_event(event);
1501 ret = 0;
1502 break;
1503
1504 case LTTNG_KERNEL_ABI_KRETPROBE:
1505 switch (event->type) {
1506 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1507 lttng_kretprobes_unregister(event);
1508 ret = 0;
1509 break;
1510 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1511 WARN_ON_ONCE(1);
1512 break;
1513 }
1514 break;
1515
1516 case LTTNG_KERNEL_ABI_SYSCALL:
1517 ret = lttng_syscall_filter_disable_event(event);
1518 break;
1519
1520 case LTTNG_KERNEL_ABI_NOOP:
1521 switch (event->type) {
1522 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1523 ret = 0;
1524 break;
1525 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1526 WARN_ON_ONCE(1);
1527 break;
1528 }
1529 break;
1530
1531 case LTTNG_KERNEL_ABI_UPROBE:
1532 lttng_uprobes_unregister_event(event);
1533 ret = 0;
1534 break;
1535
1536 case LTTNG_KERNEL_ABI_FUNCTION:
1537 lttng_fallthrough;
1538 default:
1539 WARN_ON_ONCE(1);
1540 }
1541 if (!ret)
1542 event_priv->registered = 0;
1543 return ret;
1544 }
1545
1546 /*
1547 * Only used internally at session destruction.
1548 */
1549 static
1550 void _lttng_event_destroy(struct lttng_kernel_event_common *event)
1551 {
1552 struct lttng_kernel_event_common_private *event_priv = event->priv;
1553 struct lttng_enabler_ref *enabler_ref, *tmp_enabler_ref;
1554
1555 lttng_free_event_filter_runtime(event);
1556 /* Free event enabler refs */
1557 list_for_each_entry_safe(enabler_ref, tmp_enabler_ref,
1558 &event_priv->enablers_ref_head, node)
1559 kfree(enabler_ref);
1560
1561 switch (event->type) {
1562 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1563 {
1564 struct lttng_kernel_event_recorder *event_recorder =
1565 container_of(event, struct lttng_kernel_event_recorder, parent);
1566
1567 switch (event_priv->instrumentation) {
1568 case LTTNG_KERNEL_ABI_TRACEPOINT:
1569 lttng_event_desc_put(event_priv->desc);
1570 break;
1571
1572 case LTTNG_KERNEL_ABI_KPROBE:
1573 module_put(event_priv->desc->owner);
1574 lttng_kprobes_destroy_event_private(&event_recorder->parent);
1575 break;
1576
1577 case LTTNG_KERNEL_ABI_KRETPROBE:
1578 module_put(event_priv->desc->owner);
1579 lttng_kretprobes_destroy_private(&event_recorder->parent);
1580 break;
1581
1582 case LTTNG_KERNEL_ABI_SYSCALL:
1583 break;
1584
1585 case LTTNG_KERNEL_ABI_UPROBE:
1586 module_put(event_priv->desc->owner);
1587 lttng_uprobes_destroy_event_private(&event_recorder->parent);
1588 break;
1589
1590 case LTTNG_KERNEL_ABI_FUNCTION:
1591 lttng_fallthrough;
1592 case LTTNG_KERNEL_ABI_NOOP:
1593 lttng_fallthrough;
1594 default:
1595 WARN_ON_ONCE(1);
1596 }
1597 list_del(&event_recorder->priv->node);
1598 kmem_cache_free(event_recorder_private_cache, event_recorder->priv);
1599 kmem_cache_free(event_recorder_cache, event_recorder);
1600 break;
1601 }
1602 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1603 {
1604 struct lttng_kernel_event_notifier *event_notifier =
1605 container_of(event, struct lttng_kernel_event_notifier, parent);
1606
1607 switch (event_notifier->priv->parent.instrumentation) {
1608 case LTTNG_KERNEL_ABI_TRACEPOINT:
1609 lttng_event_desc_put(event_notifier->priv->parent.desc);
1610 break;
1611
1612 case LTTNG_KERNEL_ABI_KPROBE:
1613 module_put(event_notifier->priv->parent.desc->owner);
1614 lttng_kprobes_destroy_event_private(&event_notifier->parent);
1615 break;
1616
1617 case LTTNG_KERNEL_ABI_SYSCALL:
1618 break;
1619
1620 case LTTNG_KERNEL_ABI_UPROBE:
1621 module_put(event_notifier->priv->parent.desc->owner);
1622 lttng_uprobes_destroy_event_private(&event_notifier->parent);
1623 break;
1624
1625 case LTTNG_KERNEL_ABI_KRETPROBE:
1626 lttng_fallthrough;
1627 case LTTNG_KERNEL_ABI_FUNCTION:
1628 lttng_fallthrough;
1629 case LTTNG_KERNEL_ABI_NOOP:
1630 lttng_fallthrough;
1631 default:
1632 WARN_ON_ONCE(1);
1633 }
1634 list_del(&event_notifier->priv->node);
1635 kmem_cache_free(event_notifier_private_cache, event_notifier->priv);
1636 kmem_cache_free(event_notifier_cache, event_notifier);
1637 break;
1638 }
1639 default:
1640 WARN_ON_ONCE(1);
1641 }
1642 }
1643
1644 struct lttng_kernel_id_tracker *get_tracker(struct lttng_kernel_session *session,
1645 enum tracker_type tracker_type)
1646 {
1647 switch (tracker_type) {
1648 case TRACKER_PID:
1649 return &session->pid_tracker;
1650 case TRACKER_VPID:
1651 return &session->vpid_tracker;
1652 case TRACKER_UID:
1653 return &session->uid_tracker;
1654 case TRACKER_VUID:
1655 return &session->vuid_tracker;
1656 case TRACKER_GID:
1657 return &session->gid_tracker;
1658 case TRACKER_VGID:
1659 return &session->vgid_tracker;
1660 default:
1661 WARN_ON_ONCE(1);
1662 return NULL;
1663 }
1664 }
1665
1666 int lttng_session_track_id(struct lttng_kernel_session *session,
1667 enum tracker_type tracker_type, int id)
1668 {
1669 struct lttng_kernel_id_tracker *tracker;
1670 int ret;
1671
1672 tracker = get_tracker(session, tracker_type);
1673 if (!tracker)
1674 return -EINVAL;
1675 if (id < -1)
1676 return -EINVAL;
1677 mutex_lock(&sessions_mutex);
1678 if (id == -1) {
1679 /* track all ids: destroy tracker. */
1680 lttng_id_tracker_destroy(tracker, true);
1681 ret = 0;
1682 } else {
1683 ret = lttng_id_tracker_add(tracker, id);
1684 }
1685 mutex_unlock(&sessions_mutex);
1686 return ret;
1687 }
1688
1689 int lttng_session_untrack_id(struct lttng_kernel_session *session,
1690 enum tracker_type tracker_type, int id)
1691 {
1692 struct lttng_kernel_id_tracker *tracker;
1693 int ret;
1694
1695 tracker = get_tracker(session, tracker_type);
1696 if (!tracker)
1697 return -EINVAL;
1698 if (id < -1)
1699 return -EINVAL;
1700 mutex_lock(&sessions_mutex);
1701 if (id == -1) {
1702 /* untrack all ids: replace by empty tracker. */
1703 ret = lttng_id_tracker_empty_set(tracker);
1704 } else {
1705 ret = lttng_id_tracker_del(tracker, id);
1706 }
1707 mutex_unlock(&sessions_mutex);
1708 return ret;
1709 }
1710
1711 static
1712 void *id_list_start(struct seq_file *m, loff_t *pos)
1713 {
1714 struct lttng_kernel_id_tracker *id_tracker = m->private;
1715 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1716 struct lttng_id_hash_node *e;
1717 int iter = 0, i;
1718
1719 mutex_lock(&sessions_mutex);
1720 if (id_tracker_p) {
1721 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1722 struct hlist_head *head = &id_tracker_p->id_hash[i];
1723
1724 lttng_hlist_for_each_entry(e, head, hlist) {
1725 if (iter++ >= *pos)
1726 return e;
1727 }
1728 }
1729 } else {
1730 /* ID tracker disabled. */
1731 if (iter >= *pos && iter == 0) {
1732 return id_tracker_p; /* empty tracker */
1733 }
1734 iter++;
1735 }
1736 /* End of list */
1737 return NULL;
1738 }
1739
1740 /* Called with sessions_mutex held. */
1741 static
1742 void *id_list_next(struct seq_file *m, void *p, loff_t *ppos)
1743 {
1744 struct lttng_kernel_id_tracker *id_tracker = m->private;
1745 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1746 struct lttng_id_hash_node *e;
1747 int iter = 0, i;
1748
1749 (*ppos)++;
1750 if (id_tracker_p) {
1751 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1752 struct hlist_head *head = &id_tracker_p->id_hash[i];
1753
1754 lttng_hlist_for_each_entry(e, head, hlist) {
1755 if (iter++ >= *ppos)
1756 return e;
1757 }
1758 }
1759 } else {
1760 /* ID tracker disabled. */
1761 if (iter >= *ppos && iter == 0)
1762 return p; /* empty tracker */
1763 iter++;
1764 }
1765
1766 /* End of list */
1767 return NULL;
1768 }
1769
1770 static
1771 void id_list_stop(struct seq_file *m, void *p)
1772 {
1773 mutex_unlock(&sessions_mutex);
1774 }
1775
1776 static
1777 int id_list_show(struct seq_file *m, void *p)
1778 {
1779 struct lttng_kernel_id_tracker *id_tracker = m->private;
1780 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1781 int id;
1782
1783 if (p == id_tracker_p) {
1784 /* Tracker disabled. */
1785 id = -1;
1786 } else {
1787 const struct lttng_id_hash_node *e = p;
1788
1789 id = lttng_id_tracker_get_node_id(e);
1790 }
1791 switch (id_tracker->priv->tracker_type) {
1792 case TRACKER_PID:
1793 seq_printf(m, "process { pid = %d; };\n", id);
1794 break;
1795 case TRACKER_VPID:
1796 seq_printf(m, "process { vpid = %d; };\n", id);
1797 break;
1798 case TRACKER_UID:
1799 seq_printf(m, "user { uid = %d; };\n", id);
1800 break;
1801 case TRACKER_VUID:
1802 seq_printf(m, "user { vuid = %d; };\n", id);
1803 break;
1804 case TRACKER_GID:
1805 seq_printf(m, "group { gid = %d; };\n", id);
1806 break;
1807 case TRACKER_VGID:
1808 seq_printf(m, "group { vgid = %d; };\n", id);
1809 break;
1810 default:
1811 seq_printf(m, "UNKNOWN { field = %d };\n", id);
1812 }
1813 return 0;
1814 }
1815
1816 static
1817 const struct seq_operations lttng_tracker_ids_list_seq_ops = {
1818 .start = id_list_start,
1819 .next = id_list_next,
1820 .stop = id_list_stop,
1821 .show = id_list_show,
1822 };
1823
1824 static
1825 int lttng_tracker_ids_list_open(struct inode *inode, struct file *file)
1826 {
1827 return seq_open(file, &lttng_tracker_ids_list_seq_ops);
1828 }
1829
1830 static
1831 int lttng_tracker_ids_list_release(struct inode *inode, struct file *file)
1832 {
1833 struct seq_file *m = file->private_data;
1834 struct lttng_kernel_id_tracker *id_tracker = m->private;
1835 int ret;
1836
1837 WARN_ON_ONCE(!id_tracker);
1838 ret = seq_release(inode, file);
1839 if (!ret)
1840 fput(id_tracker->priv->session->priv->file);
1841 return ret;
1842 }
1843
1844 const struct file_operations lttng_tracker_ids_list_fops = {
1845 .owner = THIS_MODULE,
1846 .open = lttng_tracker_ids_list_open,
1847 .read = seq_read,
1848 .llseek = seq_lseek,
1849 .release = lttng_tracker_ids_list_release,
1850 };
1851
1852 int lttng_session_list_tracker_ids(struct lttng_kernel_session *session,
1853 enum tracker_type tracker_type)
1854 {
1855 struct file *tracker_ids_list_file;
1856 struct seq_file *m;
1857 int file_fd, ret;
1858
1859 file_fd = lttng_get_unused_fd();
1860 if (file_fd < 0) {
1861 ret = file_fd;
1862 goto fd_error;
1863 }
1864
1865 tracker_ids_list_file = anon_inode_getfile("[lttng_tracker_ids_list]",
1866 &lttng_tracker_ids_list_fops,
1867 NULL, O_RDWR);
1868 if (IS_ERR(tracker_ids_list_file)) {
1869 ret = PTR_ERR(tracker_ids_list_file);
1870 goto file_error;
1871 }
1872 if (!atomic_long_add_unless(&session->priv->file->f_count, 1, LONG_MAX)) {
1873 ret = -EOVERFLOW;
1874 goto refcount_error;
1875 }
1876 ret = lttng_tracker_ids_list_fops.open(NULL, tracker_ids_list_file);
1877 if (ret < 0)
1878 goto open_error;
1879 m = tracker_ids_list_file->private_data;
1880
1881 m->private = get_tracker(session, tracker_type);
1882 BUG_ON(!m->private);
1883 fd_install(file_fd, tracker_ids_list_file);
1884
1885 return file_fd;
1886
1887 open_error:
1888 atomic_long_dec(&session->priv->file->f_count);
1889 refcount_error:
1890 fput(tracker_ids_list_file);
1891 file_error:
1892 put_unused_fd(file_fd);
1893 fd_error:
1894 return ret;
1895 }
1896
1897 /*
1898 * Enabler management.
1899 */
1900 static
1901 int lttng_match_enabler_star_glob(const char *desc_name,
1902 const char *pattern)
1903 {
1904 if (!strutils_star_glob_match(pattern, LTTNG_SIZE_MAX,
1905 desc_name, LTTNG_SIZE_MAX))
1906 return 0;
1907 return 1;
1908 }
1909
1910 static
1911 int lttng_match_enabler_name(const char *desc_name,
1912 const char *name)
1913 {
1914 if (strcmp(desc_name, name))
1915 return 0;
1916 return 1;
1917 }
1918
1919 int lttng_desc_match_enabler(const struct lttng_kernel_event_desc *desc,
1920 struct lttng_event_enabler_common *enabler)
1921 {
1922 const char *desc_name, *enabler_name;
1923 bool compat = false, entry = false;
1924
1925 enabler_name = enabler->event_param.name;
1926 switch (enabler->event_param.instrumentation) {
1927 case LTTNG_KERNEL_ABI_TRACEPOINT:
1928 desc_name = desc->event_name;
1929 switch (enabler->format_type) {
1930 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
1931 return lttng_match_enabler_star_glob(desc_name, enabler_name);
1932 case LTTNG_ENABLER_FORMAT_NAME:
1933 return lttng_match_enabler_name(desc_name, enabler_name);
1934 default:
1935 return -EINVAL;
1936 }
1937 break;
1938
1939 case LTTNG_KERNEL_ABI_SYSCALL:
1940 desc_name = desc->event_name;
1941 if (!strncmp(desc_name, "compat_", strlen("compat_"))) {
1942 desc_name += strlen("compat_");
1943 compat = true;
1944 }
1945 if (!strncmp(desc_name, "syscall_exit_",
1946 strlen("syscall_exit_"))) {
1947 desc_name += strlen("syscall_exit_");
1948 } else if (!strncmp(desc_name, "syscall_entry_",
1949 strlen("syscall_entry_"))) {
1950 desc_name += strlen("syscall_entry_");
1951 entry = true;
1952 } else {
1953 WARN_ON_ONCE(1);
1954 return -EINVAL;
1955 }
1956 switch (enabler->event_param.u.syscall.entryexit) {
1957 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
1958 break;
1959 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
1960 if (!entry)
1961 return 0;
1962 break;
1963 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
1964 if (entry)
1965 return 0;
1966 break;
1967 default:
1968 return -EINVAL;
1969 }
1970 switch (enabler->event_param.u.syscall.abi) {
1971 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
1972 break;
1973 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
1974 if (compat)
1975 return 0;
1976 break;
1977 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
1978 if (!compat)
1979 return 0;
1980 break;
1981 default:
1982 return -EINVAL;
1983 }
1984 switch (enabler->event_param.u.syscall.match) {
1985 case LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME:
1986 switch (enabler->format_type) {
1987 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
1988 return lttng_match_enabler_star_glob(desc_name, enabler_name);
1989 case LTTNG_ENABLER_FORMAT_NAME:
1990 return lttng_match_enabler_name(desc_name, enabler_name);
1991 default:
1992 return -EINVAL;
1993 }
1994 break;
1995 case LTTNG_KERNEL_ABI_SYSCALL_MATCH_NR:
1996 return -EINVAL; /* Not implemented. */
1997 default:
1998 return -EINVAL;
1999 }
2000 break;
2001
2002 default:
2003 WARN_ON_ONCE(1);
2004 return -EINVAL;
2005 }
2006 }
2007
2008 static
2009 int lttng_event_enabler_match_event(struct lttng_event_recorder_enabler *event_enabler,
2010 struct lttng_kernel_event_recorder *event_recorder)
2011 {
2012 struct lttng_event_enabler_common *base_enabler = lttng_event_recorder_enabler_as_enabler(
2013 event_enabler);
2014
2015 if (base_enabler->event_param.instrumentation != event_recorder->priv->parent.instrumentation)
2016 return 0;
2017 if (lttng_desc_match_enabler(event_recorder->priv->parent.desc, base_enabler)
2018 && event_recorder->chan == event_enabler->chan)
2019 return 1;
2020 else
2021 return 0;
2022 }
2023
2024 static
2025 int lttng_event_notifier_enabler_match_event_notifier(struct lttng_event_notifier_enabler *event_notifier_enabler,
2026 struct lttng_kernel_event_notifier *event_notifier)
2027 {
2028 struct lttng_event_enabler_common *base_enabler = lttng_event_notifier_enabler_as_enabler(
2029 event_notifier_enabler);
2030
2031 if (base_enabler->event_param.instrumentation != event_notifier->priv->parent.instrumentation)
2032 return 0;
2033 if (lttng_desc_match_enabler(event_notifier->priv->parent.desc, base_enabler)
2034 && event_notifier->priv->group == event_notifier_enabler->group
2035 && event_notifier->priv->parent.user_token == event_notifier_enabler->parent.user_token)
2036 return 1;
2037 else
2038 return 0;
2039 }
2040
2041 static
2042 struct lttng_enabler_ref *lttng_enabler_ref(
2043 struct list_head *enablers_ref_list,
2044 struct lttng_event_enabler_common *enabler)
2045 {
2046 struct lttng_enabler_ref *enabler_ref;
2047
2048 list_for_each_entry(enabler_ref, enablers_ref_list, node) {
2049 if (enabler_ref->ref == enabler)
2050 return enabler_ref;
2051 }
2052 return NULL;
2053 }
2054
2055 static
2056 void lttng_create_tracepoint_event_if_missing(struct lttng_event_recorder_enabler *event_enabler)
2057 {
2058 struct lttng_kernel_session *session = event_enabler->chan->parent.session;
2059 struct lttng_kernel_probe_desc *probe_desc;
2060 const struct lttng_kernel_event_desc *desc;
2061 int i;
2062 struct list_head *probe_list;
2063
2064 probe_list = lttng_get_probe_list_head();
2065 /*
2066 * For each probe event, if we find that a probe event matches
2067 * our enabler, create an associated lttng_event if not
2068 * already present.
2069 */
2070 list_for_each_entry(probe_desc, probe_list, head) {
2071 for (i = 0; i < probe_desc->nr_events; i++) {
2072 int found = 0;
2073 struct hlist_head *head;
2074 struct lttng_kernel_event_recorder_private *event_recorder_private;
2075 struct lttng_kernel_event_recorder *event_recorder;
2076
2077 desc = probe_desc->event_desc[i];
2078 if (!lttng_desc_match_enabler(desc,
2079 lttng_event_recorder_enabler_as_enabler(event_enabler)))
2080 continue;
2081
2082 /*
2083 * Check if already created.
2084 */
2085 head = utils_borrow_hash_table_bucket(
2086 session->priv->events_ht.table, LTTNG_EVENT_HT_SIZE,
2087 desc->event_name);
2088 lttng_hlist_for_each_entry(event_recorder_private, head, hlist) {
2089 if (event_recorder_private->parent.desc == desc
2090 && event_recorder_private->pub->chan == event_enabler->chan)
2091 found = 1;
2092 }
2093 if (found)
2094 continue;
2095
2096 /*
2097 * We need to create an event for this
2098 * event probe.
2099 */
2100 event_recorder = _lttng_kernel_event_recorder_create(event_enabler, desc);
2101 if (!event_recorder) {
2102 printk(KERN_INFO "LTTng: Unable to create event %s\n",
2103 probe_desc->event_desc[i]->event_name);
2104 }
2105 }
2106 }
2107 }
2108
2109 static
2110 void lttng_create_tracepoint_event_notifier_if_missing(struct lttng_event_notifier_enabler *event_notifier_enabler)
2111 {
2112 struct lttng_event_notifier_group *event_notifier_group = event_notifier_enabler->group;
2113 struct lttng_kernel_probe_desc *probe_desc;
2114 const struct lttng_kernel_event_desc *desc;
2115 int i;
2116 struct list_head *probe_list;
2117
2118 probe_list = lttng_get_probe_list_head();
2119 /*
2120 * For each probe event, if we find that a probe event matches
2121 * our enabler, create an associated lttng_event_notifier if not
2122 * already present.
2123 */
2124 list_for_each_entry(probe_desc, probe_list, head) {
2125 for (i = 0; i < probe_desc->nr_events; i++) {
2126 int found = 0;
2127 struct hlist_head *head;
2128 struct lttng_kernel_event_notifier_private *event_notifier_priv;
2129 struct lttng_kernel_event_notifier *event_notifier;
2130
2131 desc = probe_desc->event_desc[i];
2132 if (!lttng_desc_match_enabler(desc,
2133 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)))
2134 continue;
2135
2136 /*
2137 * Check if already created.
2138 */
2139 head = utils_borrow_hash_table_bucket(
2140 event_notifier_group->events_ht.table,
2141 LTTNG_EVENT_HT_SIZE, desc->event_name);
2142 lttng_hlist_for_each_entry(event_notifier_priv, head, hlist) {
2143 if (event_notifier_priv->parent.desc == desc
2144 && event_notifier_priv->parent.user_token == event_notifier_enabler->parent.user_token)
2145 found = 1;
2146 }
2147 if (found)
2148 continue;
2149
2150 /*
2151 * We need to create a event_notifier for this event probe.
2152 */
2153 event_notifier = _lttng_event_notifier_create(event_notifier_enabler, desc);
2154 if (IS_ERR(event_notifier)) {
2155 printk(KERN_INFO "Unable to create event_notifier %s\n",
2156 probe_desc->event_desc[i]->event_name);
2157 }
2158 }
2159 }
2160 }
2161
2162 static
2163 void lttng_create_syscall_event_if_missing(struct lttng_event_enabler_common *event_enabler)
2164 {
2165 int ret;
2166
2167 ret = lttng_syscalls_register_event(event_enabler);
2168 WARN_ON_ONCE(ret);
2169 }
2170
2171 /*
2172 * Create struct lttng_kernel_event_recorder if it is missing and present in the list of
2173 * tracepoint probes.
2174 * Should be called with sessions mutex held.
2175 */
2176 static
2177 void lttng_create_event_if_missing(struct lttng_event_recorder_enabler *event_enabler)
2178 {
2179 switch (event_enabler->parent.event_param.instrumentation) {
2180 case LTTNG_KERNEL_ABI_TRACEPOINT:
2181 lttng_create_tracepoint_event_if_missing(event_enabler);
2182 break;
2183
2184 case LTTNG_KERNEL_ABI_SYSCALL:
2185 lttng_create_syscall_event_if_missing(&event_enabler->parent);
2186 break;
2187
2188 default:
2189 WARN_ON_ONCE(1);
2190 break;
2191 }
2192 }
2193
2194 /*
2195 * Create events associated with an event_enabler (if not already present),
2196 * and add backward reference from the event to the enabler.
2197 * Should be called with sessions mutex held.
2198 */
2199 static
2200 int lttng_event_enabler_ref_events(struct lttng_event_recorder_enabler *event_enabler)
2201 {
2202 struct lttng_kernel_channel_buffer *chan = event_enabler->chan;
2203 struct lttng_kernel_session *session = event_enabler->chan->parent.session;
2204 struct lttng_event_enabler_common *base_enabler = lttng_event_recorder_enabler_as_enabler(event_enabler);
2205 struct lttng_kernel_event_recorder_private *event_recorder_priv;
2206
2207 if (base_enabler->event_param.instrumentation == LTTNG_KERNEL_ABI_SYSCALL &&
2208 base_enabler->event_param.u.syscall.abi == LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL &&
2209 base_enabler->event_param.u.syscall.match == LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME &&
2210 !strcmp(base_enabler->event_param.name, "*")) {
2211 int enabled = base_enabler->enabled;
2212 enum lttng_kernel_abi_syscall_entryexit entryexit = base_enabler->event_param.u.syscall.entryexit;
2213
2214 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRY || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2215 WRITE_ONCE(chan->priv->parent.syscall_table.syscall_all_entry, enabled);
2216
2217 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_EXIT || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2218 WRITE_ONCE(chan->priv->parent.syscall_table.syscall_all_exit, enabled);
2219 }
2220
2221 /* First ensure that probe events are created for this enabler. */
2222 lttng_create_event_if_missing(event_enabler);
2223
2224 /* For each event matching event_enabler in session event list. */
2225 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
2226 struct lttng_kernel_event_recorder *event_recorder = event_recorder_priv->pub;
2227 struct lttng_enabler_ref *enabler_ref;
2228
2229 if (!lttng_event_enabler_match_event(event_enabler, event_recorder))
2230 continue;
2231 enabler_ref = lttng_enabler_ref(&event_recorder_priv->parent.enablers_ref_head,
2232 lttng_event_recorder_enabler_as_enabler(event_enabler));
2233 if (!enabler_ref) {
2234 /*
2235 * If no backward ref, create it.
2236 * Add backward ref from event to event_enabler.
2237 */
2238 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
2239 if (!enabler_ref)
2240 return -ENOMEM;
2241 enabler_ref->ref = lttng_event_recorder_enabler_as_enabler(event_enabler);
2242 list_add(&enabler_ref->node,
2243 &event_recorder_priv->parent.enablers_ref_head);
2244 }
2245
2246 /*
2247 * Link filter bytecodes if not linked yet.
2248 */
2249 lttng_enabler_link_bytecode(event_recorder_priv->parent.desc,
2250 lttng_static_ctx,
2251 &event_recorder_priv->parent.filter_bytecode_runtime_head,
2252 &lttng_event_recorder_enabler_as_enabler(event_enabler)->filter_bytecode_head);
2253 }
2254 return 0;
2255 }
2256
2257 /*
2258 * Create struct lttng_kernel_event_notifier if it is missing and present in the list of
2259 * tracepoint probes.
2260 * Should be called with sessions mutex held.
2261 */
2262 static
2263 void lttng_create_event_notifier_if_missing(struct lttng_event_notifier_enabler *event_notifier_enabler)
2264 {
2265 switch (event_notifier_enabler->parent.event_param.instrumentation) {
2266 case LTTNG_KERNEL_ABI_TRACEPOINT:
2267 lttng_create_tracepoint_event_notifier_if_missing(event_notifier_enabler);
2268 break;
2269
2270 case LTTNG_KERNEL_ABI_SYSCALL:
2271 lttng_create_syscall_event_if_missing(&event_notifier_enabler->parent);
2272 break;
2273
2274 default:
2275 WARN_ON_ONCE(1);
2276 break;
2277 }
2278 }
2279
2280 /*
2281 * Create event_notifiers associated with a event_notifier enabler (if not already present).
2282 */
2283 static
2284 int lttng_event_notifier_enabler_ref_event_notifiers(
2285 struct lttng_event_notifier_enabler *event_notifier_enabler)
2286 {
2287 struct lttng_event_notifier_group *event_notifier_group = event_notifier_enabler->group;
2288 struct lttng_event_enabler_common *base_enabler = lttng_event_notifier_enabler_as_enabler(event_notifier_enabler);
2289 struct lttng_kernel_event_notifier_private *event_notifier_priv;
2290
2291 if (base_enabler->event_param.instrumentation == LTTNG_KERNEL_ABI_SYSCALL &&
2292 base_enabler->event_param.u.syscall.abi == LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL &&
2293 base_enabler->event_param.u.syscall.match == LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME &&
2294 !strcmp(base_enabler->event_param.name, "*")) {
2295
2296 int enabled = base_enabler->enabled;
2297 enum lttng_kernel_abi_syscall_entryexit entryexit = base_enabler->event_param.u.syscall.entryexit;
2298
2299 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRY || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2300 WRITE_ONCE(event_notifier_group->syscall_table.syscall_all_entry, enabled);
2301
2302 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_EXIT || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2303 WRITE_ONCE(event_notifier_group->syscall_table.syscall_all_exit, enabled);
2304
2305 }
2306
2307 /* First ensure that probe event_notifiers are created for this enabler. */
2308 lttng_create_event_notifier_if_missing(event_notifier_enabler);
2309
2310 /* Link the created event_notifier with its associated enabler. */
2311 list_for_each_entry(event_notifier_priv, &event_notifier_group->event_notifiers_head, node) {
2312 struct lttng_kernel_event_notifier *event_notifier = event_notifier_priv->pub;
2313 struct lttng_enabler_ref *enabler_ref;
2314
2315 if (!lttng_event_notifier_enabler_match_event_notifier(event_notifier_enabler, event_notifier))
2316 continue;
2317
2318 enabler_ref = lttng_enabler_ref(&event_notifier_priv->parent.enablers_ref_head,
2319 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler));
2320 if (!enabler_ref) {
2321 /*
2322 * If no backward ref, create it.
2323 * Add backward ref from event_notifier to enabler.
2324 */
2325 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
2326 if (!enabler_ref)
2327 return -ENOMEM;
2328
2329 enabler_ref->ref = lttng_event_notifier_enabler_as_enabler(
2330 event_notifier_enabler);
2331 list_add(&enabler_ref->node,
2332 &event_notifier_priv->parent.enablers_ref_head);
2333 }
2334
2335 /*
2336 * Link filter bytecodes if not linked yet.
2337 */
2338 lttng_enabler_link_bytecode(event_notifier_priv->parent.desc,
2339 lttng_static_ctx, &event_notifier_priv->parent.filter_bytecode_runtime_head,
2340 &lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->filter_bytecode_head);
2341
2342 /* Link capture bytecodes if not linked yet. */
2343 lttng_enabler_link_bytecode(event_notifier_priv->parent.desc,
2344 lttng_static_ctx, &event_notifier_priv->capture_bytecode_runtime_head,
2345 &event_notifier_enabler->capture_bytecode_head);
2346
2347 event_notifier_priv->num_captures = event_notifier_enabler->num_captures;
2348 }
2349 return 0;
2350 }
2351
2352 /*
2353 * Called at module load: connect the probe on all enablers matching
2354 * this event.
2355 * Called with sessions lock held.
2356 */
2357 int lttng_fix_pending_events(void)
2358 {
2359 struct lttng_kernel_session_private *session_priv;
2360
2361 list_for_each_entry(session_priv, &sessions, list)
2362 lttng_session_lazy_sync_event_enablers(session_priv->pub);
2363 return 0;
2364 }
2365
2366 static bool lttng_event_notifier_group_has_active_event_notifiers(
2367 struct lttng_event_notifier_group *event_notifier_group)
2368 {
2369 struct lttng_event_notifier_enabler *event_notifier_enabler;
2370
2371 list_for_each_entry(event_notifier_enabler, &event_notifier_group->enablers_head,
2372 node) {
2373 if (event_notifier_enabler->parent.enabled)
2374 return true;
2375 }
2376 return false;
2377 }
2378
2379 bool lttng_event_notifier_active(void)
2380 {
2381 struct lttng_event_notifier_group *event_notifier_group;
2382
2383 list_for_each_entry(event_notifier_group, &event_notifier_groups, node) {
2384 if (lttng_event_notifier_group_has_active_event_notifiers(event_notifier_group))
2385 return true;
2386 }
2387 return false;
2388 }
2389
2390 int lttng_fix_pending_event_notifiers(void)
2391 {
2392 struct lttng_event_notifier_group *event_notifier_group;
2393
2394 list_for_each_entry(event_notifier_group, &event_notifier_groups, node)
2395 lttng_event_notifier_group_sync_enablers(event_notifier_group);
2396 return 0;
2397 }
2398
2399 struct lttng_event_recorder_enabler *lttng_event_recorder_enabler_create(
2400 enum lttng_enabler_format_type format_type,
2401 struct lttng_kernel_abi_event *event_param,
2402 struct lttng_kernel_channel_buffer *chan)
2403 {
2404 struct lttng_event_recorder_enabler *event_enabler;
2405
2406 event_enabler = kzalloc(sizeof(*event_enabler), GFP_KERNEL);
2407 if (!event_enabler)
2408 return NULL;
2409 event_enabler->parent.enabler_type = LTTNG_EVENT_ENABLER_TYPE_RECORDER;
2410 event_enabler->parent.format_type = format_type;
2411 INIT_LIST_HEAD(&event_enabler->parent.filter_bytecode_head);
2412 memcpy(&event_enabler->parent.event_param, event_param,
2413 sizeof(event_enabler->parent.event_param));
2414 event_enabler->chan = chan;
2415 /* ctx left NULL */
2416 event_enabler->parent.enabled = 0;
2417 return event_enabler;
2418 }
2419
2420 void lttng_event_enabler_session_add(struct lttng_kernel_session *session,
2421 struct lttng_event_recorder_enabler *event_enabler)
2422 {
2423 mutex_lock(&sessions_mutex);
2424 list_add(&event_enabler->node, &session->priv->enablers_head);
2425 event_enabler->published = true;
2426 lttng_session_lazy_sync_event_enablers(session);
2427 mutex_unlock(&sessions_mutex);
2428 }
2429
2430 int lttng_event_enabler_enable(struct lttng_event_enabler_common *event_enabler)
2431 {
2432 mutex_lock(&sessions_mutex);
2433 event_enabler->enabled = 1;
2434 lttng_event_enabler_sync(event_enabler);
2435 mutex_unlock(&sessions_mutex);
2436 return 0;
2437 }
2438
2439 int lttng_event_enabler_disable(struct lttng_event_enabler_common *event_enabler)
2440 {
2441 mutex_lock(&sessions_mutex);
2442 event_enabler->enabled = 0;
2443 lttng_event_enabler_sync(event_enabler);
2444 mutex_unlock(&sessions_mutex);
2445 return 0;
2446 }
2447
2448 static
2449 int lttng_enabler_attach_filter_bytecode(struct lttng_event_enabler_common *enabler,
2450 struct lttng_kernel_abi_filter_bytecode __user *bytecode)
2451 {
2452 struct lttng_kernel_bytecode_node *bytecode_node;
2453 uint32_t bytecode_len;
2454 int ret;
2455
2456 ret = get_user(bytecode_len, &bytecode->len);
2457 if (ret)
2458 return ret;
2459 bytecode_node = lttng_kvzalloc(sizeof(*bytecode_node) + bytecode_len,
2460 GFP_KERNEL);
2461 if (!bytecode_node)
2462 return -ENOMEM;
2463 ret = copy_from_user(&bytecode_node->bc, bytecode,
2464 sizeof(*bytecode) + bytecode_len);
2465 if (ret)
2466 goto error_free;
2467
2468 bytecode_node->type = LTTNG_KERNEL_BYTECODE_TYPE_FILTER;
2469 bytecode_node->enabler = enabler;
2470 /* Enforce length based on allocated size */
2471 bytecode_node->bc.len = bytecode_len;
2472 list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head);
2473
2474 return 0;
2475
2476 error_free:
2477 lttng_kvfree(bytecode_node);
2478 return ret;
2479 }
2480
2481 int lttng_event_enabler_attach_filter_bytecode(struct lttng_event_enabler_common *event_enabler,
2482 struct lttng_kernel_abi_filter_bytecode __user *bytecode)
2483 {
2484 int ret;
2485 ret = lttng_enabler_attach_filter_bytecode(event_enabler, bytecode);
2486 if (ret)
2487 goto error;
2488 lttng_event_enabler_sync(event_enabler);
2489 return 0;
2490
2491 error:
2492 return ret;
2493 }
2494
2495 int lttng_event_add_callsite(struct lttng_kernel_event_common *event,
2496 struct lttng_kernel_abi_event_callsite __user *callsite)
2497 {
2498
2499 switch (event->priv->instrumentation) {
2500 case LTTNG_KERNEL_ABI_UPROBE:
2501 return lttng_uprobes_event_add_callsite(event, callsite);
2502 default:
2503 return -EINVAL;
2504 }
2505 }
2506
2507 static
2508 void lttng_enabler_destroy(struct lttng_event_enabler_common *enabler)
2509 {
2510 struct lttng_kernel_bytecode_node *filter_node, *tmp_filter_node;
2511
2512 /* Destroy filter bytecode */
2513 list_for_each_entry_safe(filter_node, tmp_filter_node,
2514 &enabler->filter_bytecode_head, node) {
2515 lttng_kvfree(filter_node);
2516 }
2517 }
2518
2519 void lttng_event_enabler_destroy(struct lttng_event_enabler_common *event_enabler)
2520 {
2521 switch (event_enabler->enabler_type) {
2522 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
2523 {
2524 struct lttng_event_recorder_enabler *event_recorder_enabler =
2525 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
2526
2527 lttng_enabler_destroy(event_enabler);
2528 if (event_recorder_enabler->published)
2529 list_del(&event_recorder_enabler->node);
2530 kfree(event_recorder_enabler);
2531 break;
2532 }
2533 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
2534 {
2535 struct lttng_event_notifier_enabler *event_notifier_enabler =
2536 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
2537
2538 lttng_enabler_destroy(event_enabler);
2539 if (event_notifier_enabler->published)
2540 list_del(&event_notifier_enabler->node);
2541 kfree(event_notifier_enabler);
2542 break;
2543 }
2544 default:
2545 WARN_ON_ONCE(1);
2546 }
2547 }
2548
2549 struct lttng_event_notifier_enabler *lttng_event_notifier_enabler_create(
2550 enum lttng_enabler_format_type format_type,
2551 struct lttng_kernel_abi_event_notifier *event_notifier_param,
2552 struct lttng_event_notifier_group *event_notifier_group)
2553 {
2554 struct lttng_event_notifier_enabler *event_notifier_enabler;
2555
2556 event_notifier_enabler = kzalloc(sizeof(*event_notifier_enabler), GFP_KERNEL);
2557 if (!event_notifier_enabler)
2558 return NULL;
2559
2560 event_notifier_enabler->parent.enabler_type = LTTNG_EVENT_ENABLER_TYPE_NOTIFIER;
2561 event_notifier_enabler->parent.format_type = format_type;
2562 INIT_LIST_HEAD(&event_notifier_enabler->parent.filter_bytecode_head);
2563 INIT_LIST_HEAD(&event_notifier_enabler->capture_bytecode_head);
2564
2565 event_notifier_enabler->error_counter_index = event_notifier_param->error_counter_index;
2566 event_notifier_enabler->num_captures = 0;
2567
2568 memcpy(&event_notifier_enabler->parent.event_param, &event_notifier_param->event,
2569 sizeof(event_notifier_enabler->parent.event_param));
2570
2571 event_notifier_enabler->parent.enabled = 0;
2572 event_notifier_enabler->parent.user_token = event_notifier_param->event.token;
2573 event_notifier_enabler->group = event_notifier_group;
2574 return event_notifier_enabler;
2575 }
2576
2577 void lttng_event_notifier_enabler_group_add(struct lttng_event_notifier_group *event_notifier_group,
2578 struct lttng_event_notifier_enabler *event_notifier_enabler)
2579 {
2580 mutex_lock(&sessions_mutex);
2581 list_add(&event_notifier_enabler->node, &event_notifier_enabler->group->enablers_head);
2582 event_notifier_enabler->published = true;
2583 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2584 mutex_unlock(&sessions_mutex);
2585 }
2586
2587 int lttng_event_notifier_enabler_enable(
2588 struct lttng_event_notifier_enabler *event_notifier_enabler)
2589 {
2590 mutex_lock(&sessions_mutex);
2591 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->enabled = 1;
2592 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2593 mutex_unlock(&sessions_mutex);
2594 return 0;
2595 }
2596
2597 int lttng_event_notifier_enabler_disable(
2598 struct lttng_event_notifier_enabler *event_notifier_enabler)
2599 {
2600 mutex_lock(&sessions_mutex);
2601 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->enabled = 0;
2602 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2603 mutex_unlock(&sessions_mutex);
2604 return 0;
2605 }
2606
2607 int lttng_event_notifier_enabler_attach_capture_bytecode(
2608 struct lttng_event_notifier_enabler *event_notifier_enabler,
2609 struct lttng_kernel_abi_capture_bytecode __user *bytecode)
2610 {
2611 struct lttng_kernel_bytecode_node *bytecode_node;
2612 struct lttng_event_enabler_common *enabler =
2613 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler);
2614 uint32_t bytecode_len;
2615 int ret;
2616
2617 ret = get_user(bytecode_len, &bytecode->len);
2618 if (ret)
2619 return ret;
2620
2621 bytecode_node = lttng_kvzalloc(sizeof(*bytecode_node) + bytecode_len,
2622 GFP_KERNEL);
2623 if (!bytecode_node)
2624 return -ENOMEM;
2625
2626 ret = copy_from_user(&bytecode_node->bc, bytecode,
2627 sizeof(*bytecode) + bytecode_len);
2628 if (ret)
2629 goto error_free;
2630
2631 bytecode_node->type = LTTNG_KERNEL_BYTECODE_TYPE_CAPTURE;
2632 bytecode_node->enabler = enabler;
2633
2634 /* Enforce length based on allocated size */
2635 bytecode_node->bc.len = bytecode_len;
2636 list_add_tail(&bytecode_node->node, &event_notifier_enabler->capture_bytecode_head);
2637
2638 event_notifier_enabler->num_captures++;
2639
2640 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2641 goto end;
2642
2643 error_free:
2644 lttng_kvfree(bytecode_node);
2645 end:
2646 return ret;
2647 }
2648
2649 /*
2650 * lttng_session_sync_event_enablers should be called just before starting a
2651 * session.
2652 * Should be called with sessions mutex held.
2653 */
2654 static
2655 void lttng_session_sync_event_enablers(struct lttng_kernel_session *session)
2656 {
2657 struct lttng_event_recorder_enabler *event_enabler;
2658 struct lttng_kernel_event_recorder_private *event_recorder_priv;
2659
2660 list_for_each_entry(event_enabler, &session->priv->enablers_head, node)
2661 lttng_event_enabler_ref_events(event_enabler);
2662 /*
2663 * For each event, if at least one of its enablers is enabled,
2664 * and its channel and session transient states are enabled, we
2665 * enable the event, else we disable it.
2666 */
2667 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
2668 struct lttng_kernel_event_recorder *event_recorder = event_recorder_priv->pub;
2669 struct lttng_enabler_ref *enabler_ref;
2670 struct lttng_kernel_bytecode_runtime *runtime;
2671 int enabled = 0, has_enablers_without_filter_bytecode = 0;
2672 int nr_filters = 0;
2673
2674 switch (event_recorder_priv->parent.instrumentation) {
2675 case LTTNG_KERNEL_ABI_TRACEPOINT:
2676 lttng_fallthrough;
2677 case LTTNG_KERNEL_ABI_SYSCALL:
2678 /* Enable events */
2679 list_for_each_entry(enabler_ref,
2680 &event_recorder_priv->parent.enablers_ref_head, node) {
2681 if (enabler_ref->ref->enabled) {
2682 enabled = 1;
2683 break;
2684 }
2685 }
2686 break;
2687
2688 default:
2689 /* Not handled with lazy sync. */
2690 continue;
2691 }
2692 /*
2693 * Enabled state is based on union of enablers, with
2694 * intesection of session and channel transient enable
2695 * states.
2696 */
2697 enabled = enabled && session->priv->tstate && event_recorder->chan->priv->parent.tstate;
2698
2699 WRITE_ONCE(event_recorder->parent.enabled, enabled);
2700 /*
2701 * Sync tracepoint registration with event enabled
2702 * state.
2703 */
2704 if (enabled) {
2705 register_event(&event_recorder->parent);
2706 } else {
2707 _lttng_event_unregister(&event_recorder->parent);
2708 }
2709
2710 /* Check if has enablers without bytecode enabled */
2711 list_for_each_entry(enabler_ref,
2712 &event_recorder_priv->parent.enablers_ref_head, node) {
2713 if (enabler_ref->ref->enabled
2714 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
2715 has_enablers_without_filter_bytecode = 1;
2716 break;
2717 }
2718 }
2719 event_recorder_priv->parent.has_enablers_without_filter_bytecode =
2720 has_enablers_without_filter_bytecode;
2721
2722 /* Enable filters */
2723 list_for_each_entry(runtime,
2724 &event_recorder_priv->parent.filter_bytecode_runtime_head, node) {
2725 lttng_bytecode_sync_state(runtime);
2726 nr_filters++;
2727 }
2728 WRITE_ONCE(event_recorder_priv->parent.pub->eval_filter,
2729 !(has_enablers_without_filter_bytecode || !nr_filters));
2730 }
2731 }
2732
2733 /*
2734 * Apply enablers to session events, adding events to session if need
2735 * be. It is required after each modification applied to an active
2736 * session, and right before session "start".
2737 * "lazy" sync means we only sync if required.
2738 * Should be called with sessions mutex held.
2739 */
2740 static
2741 void lttng_session_lazy_sync_event_enablers(struct lttng_kernel_session *session)
2742 {
2743 /* We can skip if session is not active */
2744 if (!session->active)
2745 return;
2746 lttng_session_sync_event_enablers(session);
2747 }
2748
2749 static
2750 void lttng_event_notifier_group_sync_enablers(struct lttng_event_notifier_group *event_notifier_group)
2751 {
2752 struct lttng_event_notifier_enabler *event_notifier_enabler;
2753 struct lttng_kernel_event_notifier_private *event_notifier_priv;
2754
2755 list_for_each_entry(event_notifier_enabler, &event_notifier_group->enablers_head, node)
2756 lttng_event_notifier_enabler_ref_event_notifiers(event_notifier_enabler);
2757
2758 /*
2759 * For each event_notifier, if at least one of its enablers is enabled,
2760 * we enable the event_notifier, else we disable it.
2761 */
2762 list_for_each_entry(event_notifier_priv, &event_notifier_group->event_notifiers_head, node) {
2763 struct lttng_kernel_event_notifier *event_notifier = event_notifier_priv->pub;
2764 struct lttng_enabler_ref *enabler_ref;
2765 struct lttng_kernel_bytecode_runtime *runtime;
2766 int enabled = 0, has_enablers_without_filter_bytecode = 0;
2767 int nr_filters = 0, nr_captures = 0;
2768
2769 switch (event_notifier_priv->parent.instrumentation) {
2770 case LTTNG_KERNEL_ABI_TRACEPOINT:
2771 lttng_fallthrough;
2772 case LTTNG_KERNEL_ABI_SYSCALL:
2773 /* Enable event_notifiers */
2774 list_for_each_entry(enabler_ref,
2775 &event_notifier_priv->parent.enablers_ref_head, node) {
2776 if (enabler_ref->ref->enabled) {
2777 enabled = 1;
2778 break;
2779 }
2780 }
2781 break;
2782
2783 default:
2784 /* Not handled with sync. */
2785 continue;
2786 }
2787
2788 WRITE_ONCE(event_notifier->parent.enabled, enabled);
2789 /*
2790 * Sync tracepoint registration with event_notifier enabled
2791 * state.
2792 */
2793 if (enabled) {
2794 if (!event_notifier_priv->parent.registered)
2795 register_event(&event_notifier->parent);
2796 } else {
2797 if (event_notifier_priv->parent.registered)
2798 _lttng_event_unregister(&event_notifier->parent);
2799 }
2800
2801 /* Check if has enablers without bytecode enabled */
2802 list_for_each_entry(enabler_ref,
2803 &event_notifier_priv->parent.enablers_ref_head, node) {
2804 if (enabler_ref->ref->enabled
2805 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
2806 has_enablers_without_filter_bytecode = 1;
2807 break;
2808 }
2809 }
2810 event_notifier_priv->parent.has_enablers_without_filter_bytecode =
2811 has_enablers_without_filter_bytecode;
2812
2813 /* Enable filters */
2814 list_for_each_entry(runtime,
2815 &event_notifier_priv->parent.filter_bytecode_runtime_head, node) {
2816 lttng_bytecode_sync_state(runtime);
2817 nr_filters++;
2818 }
2819 WRITE_ONCE(event_notifier_priv->parent.pub->eval_filter,
2820 !(has_enablers_without_filter_bytecode || !nr_filters));
2821
2822 /* Enable captures */
2823 list_for_each_entry(runtime,
2824 &event_notifier_priv->capture_bytecode_runtime_head, node) {
2825 lttng_bytecode_sync_state(runtime);
2826 nr_captures++;
2827 }
2828 WRITE_ONCE(event_notifier->eval_capture, !!nr_captures);
2829 }
2830 }
2831
2832 static
2833 void lttng_event_enabler_sync(struct lttng_event_enabler_common *event_enabler)
2834 {
2835 switch (event_enabler->enabler_type) {
2836 case LTTNG_EVENT_ENABLER_TYPE_RECORDER:
2837 {
2838 struct lttng_event_recorder_enabler *event_recorder_enabler =
2839 container_of(event_enabler, struct lttng_event_recorder_enabler, parent);
2840 lttng_session_lazy_sync_event_enablers(event_recorder_enabler->chan->parent.session);
2841 break;
2842 }
2843 case LTTNG_EVENT_ENABLER_TYPE_NOTIFIER:
2844 {
2845 struct lttng_event_notifier_enabler *event_notifier_enabler =
2846 container_of(event_enabler, struct lttng_event_notifier_enabler, parent);
2847 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2848 break;
2849 }
2850 default:
2851 WARN_ON_ONCE(1);
2852 }
2853 }
2854
2855 /*
2856 * Serialize at most one packet worth of metadata into a metadata
2857 * channel.
2858 * We grab the metadata cache mutex to get exclusive access to our metadata
2859 * buffer and to the metadata cache. Exclusive access to the metadata buffer
2860 * allows us to do racy operations such as looking for remaining space left in
2861 * packet and write, since mutual exclusion protects us from concurrent writes.
2862 * Mutual exclusion on the metadata cache allow us to read the cache content
2863 * without racing against reallocation of the cache by updates.
2864 * Returns the number of bytes written in the channel, 0 if no data
2865 * was written and a negative value on error.
2866 */
2867 int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
2868 struct lttng_kernel_ring_buffer_channel *chan, bool *coherent)
2869 {
2870 struct lttng_kernel_ring_buffer_ctx ctx;
2871 int ret = 0;
2872 size_t len, reserve_len;
2873
2874 /*
2875 * Ensure we support mutiple get_next / put sequences followed by
2876 * put_next. The metadata cache lock protects reading the metadata
2877 * cache. It can indeed be read concurrently by "get_next_subbuf" and
2878 * "flush" operations on the buffer invoked by different processes.
2879 * Moreover, since the metadata cache memory can be reallocated, we
2880 * need to have exclusive access against updates even though we only
2881 * read it.
2882 */
2883 mutex_lock(&stream->metadata_cache->lock);
2884 WARN_ON(stream->metadata_in < stream->metadata_out);
2885 if (stream->metadata_in != stream->metadata_out)
2886 goto end;
2887
2888 /* Metadata regenerated, change the version. */
2889 if (stream->metadata_cache->version != stream->version)
2890 stream->version = stream->metadata_cache->version;
2891
2892 len = stream->metadata_cache->metadata_written -
2893 stream->metadata_in;
2894 if (!len)
2895 goto end;
2896 reserve_len = min_t(size_t,
2897 stream->transport->ops.priv->packet_avail_size(chan),
2898 len);
2899 lib_ring_buffer_ctx_init(&ctx, chan, reserve_len,
2900 sizeof(char), NULL);
2901 /*
2902 * If reservation failed, return an error to the caller.
2903 */
2904 ret = stream->transport->ops.event_reserve(&ctx);
2905 if (ret != 0) {
2906 printk(KERN_WARNING "LTTng: Metadata event reservation failed\n");
2907 stream->coherent = false;
2908 goto end;
2909 }
2910 stream->transport->ops.event_write(&ctx,
2911 stream->metadata_cache->data + stream->metadata_in,
2912 reserve_len, 1);
2913 stream->transport->ops.event_commit(&ctx);
2914 stream->metadata_in += reserve_len;
2915 if (reserve_len < len)
2916 stream->coherent = false;
2917 else
2918 stream->coherent = true;
2919 ret = reserve_len;
2920
2921 end:
2922 if (coherent)
2923 *coherent = stream->coherent;
2924 mutex_unlock(&stream->metadata_cache->lock);
2925 return ret;
2926 }
2927
2928 static
2929 void lttng_metadata_begin(struct lttng_kernel_session *session)
2930 {
2931 if (atomic_inc_return(&session->priv->metadata_cache->producing) == 1)
2932 mutex_lock(&session->priv->metadata_cache->lock);
2933 }
2934
2935 static
2936 void lttng_metadata_end(struct lttng_kernel_session *session)
2937 {
2938 WARN_ON_ONCE(!atomic_read(&session->priv->metadata_cache->producing));
2939 if (atomic_dec_return(&session->priv->metadata_cache->producing) == 0) {
2940 struct lttng_metadata_stream *stream;
2941
2942 list_for_each_entry(stream, &session->priv->metadata_cache->metadata_stream, list)
2943 wake_up_interruptible(&stream->read_wait);
2944 mutex_unlock(&session->priv->metadata_cache->lock);
2945 }
2946 }
2947
2948 /*
2949 * Write the metadata to the metadata cache.
2950 * Must be called with sessions_mutex held.
2951 * The metadata cache lock protects us from concurrent read access from
2952 * thread outputting metadata content to ring buffer.
2953 * The content of the printf is printed as a single atomic metadata
2954 * transaction.
2955 */
2956 int lttng_metadata_printf(struct lttng_kernel_session *session,
2957 const char *fmt, ...)
2958 {
2959 char *str;
2960 size_t len;
2961 va_list ap;
2962
2963 WARN_ON_ONCE(!LTTNG_READ_ONCE(session->active));
2964
2965 va_start(ap, fmt);
2966 str = kvasprintf(GFP_KERNEL, fmt, ap);
2967 va_end(ap);
2968 if (!str)
2969 return -ENOMEM;
2970
2971 len = strlen(str);
2972 WARN_ON_ONCE(!atomic_read(&session->priv->metadata_cache->producing));
2973 if (session->priv->metadata_cache->metadata_written + len >
2974 session->priv->metadata_cache->cache_alloc) {
2975 char *tmp_cache_realloc;
2976 unsigned int tmp_cache_alloc_size;
2977
2978 tmp_cache_alloc_size = max_t(unsigned int,
2979 session->priv->metadata_cache->cache_alloc + len,
2980 session->priv->metadata_cache->cache_alloc << 1);
2981 tmp_cache_realloc = vzalloc(tmp_cache_alloc_size);
2982 if (!tmp_cache_realloc)
2983 goto err;
2984 if (session->priv->metadata_cache->data) {
2985 memcpy(tmp_cache_realloc,
2986 session->priv->metadata_cache->data,
2987 session->priv->metadata_cache->cache_alloc);
2988 vfree(session->priv->metadata_cache->data);
2989 }
2990
2991 session->priv->metadata_cache->cache_alloc = tmp_cache_alloc_size;
2992 session->priv->metadata_cache->data = tmp_cache_realloc;
2993 }
2994 memcpy(session->priv->metadata_cache->data +
2995 session->priv->metadata_cache->metadata_written,
2996 str, len);
2997 session->priv->metadata_cache->metadata_written += len;
2998 kfree(str);
2999
3000 return 0;
3001
3002 err:
3003 kfree(str);
3004 return -ENOMEM;
3005 }
3006
3007 static
3008 int print_tabs(struct lttng_kernel_session *session, size_t nesting)
3009 {
3010 size_t i;
3011
3012 for (i = 0; i < nesting; i++) {
3013 int ret;
3014
3015 ret = lttng_metadata_printf(session, " ");
3016 if (ret) {
3017 return ret;
3018 }
3019 }
3020 return 0;
3021 }
3022
3023 static
3024 int lttng_field_name_statedump(struct lttng_kernel_session *session,
3025 const struct lttng_kernel_event_field *field,
3026 size_t nesting)
3027 {
3028 return lttng_metadata_printf(session, " _%s;\n", field->name);
3029 }
3030
3031 static
3032 int _lttng_integer_type_statedump(struct lttng_kernel_session *session,
3033 const struct lttng_kernel_type_integer *type,
3034 enum lttng_kernel_string_encoding parent_encoding,
3035 size_t nesting)
3036 {
3037 int ret;
3038
3039 ret = print_tabs(session, nesting);
3040 if (ret)
3041 return ret;
3042 ret = lttng_metadata_printf(session,
3043 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s }",
3044 type->size,
3045 type->alignment,
3046 type->signedness,
3047 (parent_encoding == lttng_kernel_string_encoding_none)
3048 ? "none"
3049 : (parent_encoding == lttng_kernel_string_encoding_UTF8)
3050 ? "UTF8"
3051 : "ASCII",
3052 type->base,
3053 #if __BYTE_ORDER == __BIG_ENDIAN
3054 type->reverse_byte_order ? " byte_order = le;" : ""
3055 #else
3056 type->reverse_byte_order ? " byte_order = be;" : ""
3057 #endif
3058 );
3059 return ret;
3060 }
3061
3062 /*
3063 * Must be called with sessions_mutex held.
3064 */
3065 static
3066 int _lttng_struct_type_statedump(struct lttng_kernel_session *session,
3067 const struct lttng_kernel_type_struct *type,
3068 size_t nesting)
3069 {
3070 const char *prev_field_name = NULL;
3071 int ret;
3072 uint32_t i, nr_fields;
3073 unsigned int alignment;
3074
3075 ret = print_tabs(session, nesting);
3076 if (ret)
3077 return ret;
3078 ret = lttng_metadata_printf(session,
3079 "struct {\n");
3080 if (ret)
3081 return ret;
3082 nr_fields = type->nr_fields;
3083 for (i = 0; i < nr_fields; i++) {
3084 const struct lttng_kernel_event_field *iter_field;
3085
3086 iter_field = type->fields[i];
3087 ret = _lttng_field_statedump(session, iter_field, nesting + 1, &prev_field_name);
3088 if (ret)
3089 return ret;
3090 }
3091 ret = print_tabs(session, nesting);
3092 if (ret)
3093 return ret;
3094 alignment = type->alignment;
3095 if (alignment) {
3096 ret = lttng_metadata_printf(session,
3097 "} align(%u)",
3098 alignment);
3099 } else {
3100 ret = lttng_metadata_printf(session,
3101 "}");
3102 }
3103 return ret;
3104 }
3105
3106 /*
3107 * Must be called with sessions_mutex held.
3108 */
3109 static
3110 int _lttng_struct_field_statedump(struct lttng_kernel_session *session,
3111 const struct lttng_kernel_event_field *field,
3112 size_t nesting)
3113 {
3114 int ret;
3115
3116 ret = _lttng_struct_type_statedump(session,
3117 lttng_kernel_get_type_struct(field->type), nesting);
3118 if (ret)
3119 return ret;
3120 return lttng_field_name_statedump(session, field, nesting);
3121 }
3122
3123 /*
3124 * Must be called with sessions_mutex held.
3125 */
3126 static
3127 int _lttng_variant_type_statedump(struct lttng_kernel_session *session,
3128 const struct lttng_kernel_type_variant *type,
3129 size_t nesting,
3130 const char *prev_field_name)
3131 {
3132 const char *tag_name;
3133 int ret;
3134 uint32_t i, nr_choices;
3135
3136 tag_name = type->tag_name;
3137 if (!tag_name)
3138 tag_name = prev_field_name;
3139 if (!tag_name)
3140 return -EINVAL;
3141 /*
3142 * CTF 1.8 does not allow expressing nonzero variant alignment in a nestable way.
3143 */
3144 if (type->alignment != 0)
3145 return -EINVAL;
3146 ret = print_tabs(session, nesting);
3147 if (ret)
3148 return ret;
3149 ret = lttng_metadata_printf(session,
3150 "variant <_%s> {\n",
3151 tag_name);
3152 if (ret)
3153 return ret;
3154 nr_choices = type->nr_choices;
3155 for (i = 0; i < nr_choices; i++) {
3156 const struct lttng_kernel_event_field *iter_field;
3157
3158 iter_field = type->choices[i];
3159 ret = _lttng_field_statedump(session, iter_field, nesting + 1, NULL);
3160 if (ret)
3161 return ret;
3162 }
3163 ret = print_tabs(session, nesting);
3164 if (ret)
3165 return ret;
3166 ret = lttng_metadata_printf(session,
3167 "}");
3168 return ret;
3169 }
3170
3171 /*
3172 * Must be called with sessions_mutex held.
3173 */
3174 static
3175 int _lttng_variant_field_statedump(struct lttng_kernel_session *session,
3176 const struct lttng_kernel_event_field *field,
3177 size_t nesting,
3178 const char *prev_field_name)
3179 {
3180 int ret;
3181
3182 ret = _lttng_variant_type_statedump(session,
3183 lttng_kernel_get_type_variant(field->type), nesting,
3184 prev_field_name);
3185 if (ret)
3186 return ret;
3187 return lttng_field_name_statedump(session, field, nesting);
3188 }
3189
3190 /*
3191 * Must be called with sessions_mutex held.
3192 */
3193 static
3194 int _lttng_array_field_statedump(struct lttng_kernel_session *session,
3195 const struct lttng_kernel_event_field *field,
3196 size_t nesting)
3197 {
3198 int ret;
3199 const struct lttng_kernel_type_array *array_type;
3200 const struct lttng_kernel_type_common *elem_type;
3201
3202 array_type = lttng_kernel_get_type_array(field->type);
3203 WARN_ON_ONCE(!array_type);
3204
3205 if (array_type->alignment) {
3206 ret = print_tabs(session, nesting);
3207 if (ret)
3208 return ret;
3209 ret = lttng_metadata_printf(session,
3210 "struct { } align(%u) _%s_padding;\n",
3211 array_type->alignment * CHAR_BIT,
3212 field->name);
3213 if (ret)
3214 return ret;
3215 }
3216 /*
3217 * Nested compound types: Only array of structures and variants are
3218 * currently supported.
3219 */
3220 elem_type = array_type->elem_type;
3221 switch (elem_type->type) {
3222 case lttng_kernel_type_integer:
3223 case lttng_kernel_type_struct:
3224 case lttng_kernel_type_variant:
3225 ret = _lttng_type_statedump(session, elem_type,
3226 array_type->encoding, nesting);
3227 if (ret)
3228 return ret;
3229 break;
3230
3231 default:
3232 return -EINVAL;
3233 }
3234 ret = lttng_metadata_printf(session,
3235 " _%s[%u];\n",
3236 field->name,
3237 array_type->length);
3238 return ret;
3239 }
3240
3241 /*
3242 * Must be called with sessions_mutex held.
3243 */
3244 static
3245 int _lttng_sequence_field_statedump(struct lttng_kernel_session *session,
3246 const struct lttng_kernel_event_field *field,
3247 size_t nesting,
3248 const char *prev_field_name)
3249 {
3250 int ret;
3251 const char *length_name;
3252 const struct lttng_kernel_type_sequence *sequence_type;
3253 const struct lttng_kernel_type_common *elem_type;
3254
3255 sequence_type = lttng_kernel_get_type_sequence(field->type);
3256 WARN_ON_ONCE(!sequence_type);
3257
3258 length_name = sequence_type->length_name;
3259 if (!length_name)
3260 length_name = prev_field_name;
3261 if (!length_name)
3262 return -EINVAL;
3263
3264 if (sequence_type->alignment) {
3265 ret = print_tabs(session, nesting);
3266 if (ret)
3267 return ret;
3268 ret = lttng_metadata_printf(session,
3269 "struct { } align(%u) _%s_padding;\n",
3270 sequence_type->alignment * CHAR_BIT,
3271 field->name);
3272 if (ret)
3273 return ret;
3274 }
3275
3276 /*
3277 * Nested compound types: Only array of structures and variants are
3278 * currently supported.
3279 */
3280 elem_type = sequence_type->elem_type;
3281 switch (elem_type->type) {
3282 case lttng_kernel_type_integer:
3283 case lttng_kernel_type_struct:
3284 case lttng_kernel_type_variant:
3285 ret = _lttng_type_statedump(session, elem_type,
3286 sequence_type->encoding, nesting);
3287 if (ret)
3288 return ret;
3289 break;
3290
3291 default:
3292 return -EINVAL;
3293 }
3294 ret = lttng_metadata_printf(session,
3295 " _%s[ _%s ];\n",
3296 field->name,
3297 length_name);
3298 return ret;
3299 }
3300
3301 /*
3302 * Must be called with sessions_mutex held.
3303 */
3304 static
3305 int _lttng_enum_type_statedump(struct lttng_kernel_session *session,
3306 const struct lttng_kernel_type_enum *type,
3307 size_t nesting)
3308 {
3309 const struct lttng_kernel_enum_desc *enum_desc;
3310 const struct lttng_kernel_type_common *container_type;
3311 int ret;
3312 unsigned int i, nr_entries;
3313
3314 container_type = type->container_type;
3315 if (container_type->type != lttng_kernel_type_integer) {
3316 ret = -EINVAL;
3317 goto end;
3318 }
3319 enum_desc = type->desc;
3320 nr_entries = enum_desc->nr_entries;
3321
3322 ret = print_tabs(session, nesting);
3323 if (ret)
3324 goto end;
3325 ret = lttng_metadata_printf(session, "enum : ");
3326 if (ret)
3327 goto end;
3328 ret = _lttng_integer_type_statedump(session, lttng_kernel_get_type_integer(container_type),
3329 lttng_kernel_string_encoding_none, 0);
3330 if (ret)
3331 goto end;
3332 ret = lttng_metadata_printf(session, " {\n");
3333 if (ret)
3334 goto end;
3335 /* Dump all entries */
3336 for (i = 0; i < nr_entries; i++) {
3337 const struct lttng_kernel_enum_entry *entry = enum_desc->entries[i];
3338 int j, len;
3339
3340 ret = print_tabs(session, nesting + 1);
3341 if (ret)
3342 goto end;
3343 ret = lttng_metadata_printf(session,
3344 "\"");
3345 if (ret)
3346 goto end;
3347 len = strlen(entry->string);
3348 /* Escape the character '"' */
3349 for (j = 0; j < len; j++) {
3350 char c = entry->string[j];
3351
3352 switch (c) {
3353 case '"':
3354 ret = lttng_metadata_printf(session,
3355 "\\\"");
3356 break;
3357 case '\\':
3358 ret = lttng_metadata_printf(session,
3359 "\\\\");
3360 break;
3361 default:
3362 ret = lttng_metadata_printf(session,
3363 "%c", c);
3364 break;
3365 }
3366 if (ret)
3367 goto end;
3368 }
3369 ret = lttng_metadata_printf(session, "\"");
3370 if (ret)
3371 goto end;
3372
3373 if (entry->options.is_auto) {
3374 ret = lttng_metadata_printf(session, ",\n");
3375 if (ret)
3376 goto end;
3377 } else {
3378 ret = lttng_metadata_printf(session,
3379 " = ");
3380 if (ret)
3381 goto end;
3382 if (entry->start.signedness)
3383 ret = lttng_metadata_printf(session,
3384 "%lld", (long long) entry->start.value);
3385 else
3386 ret = lttng_metadata_printf(session,
3387 "%llu", entry->start.value);
3388 if (ret)
3389 goto end;
3390 if (entry->start.signedness == entry->end.signedness &&
3391 entry->start.value
3392 == entry->end.value) {
3393 ret = lttng_metadata_printf(session,
3394 ",\n");
3395 } else {
3396 if (entry->end.signedness) {
3397 ret = lttng_metadata_printf(session,
3398 " ... %lld,\n",
3399 (long long) entry->end.value);
3400 } else {
3401 ret = lttng_metadata_printf(session,
3402 " ... %llu,\n",
3403 entry->end.value);
3404 }
3405 }
3406 if (ret)
3407 goto end;
3408 }
3409 }
3410 ret = print_tabs(session, nesting);
3411 if (ret)
3412 goto end;
3413 ret = lttng_metadata_printf(session, "}");
3414 end:
3415 return ret;
3416 }
3417
3418 /*
3419 * Must be called with sessions_mutex held.
3420 */
3421 static
3422 int _lttng_enum_field_statedump(struct lttng_kernel_session *session,
3423 const struct lttng_kernel_event_field *field,
3424 size_t nesting)
3425 {
3426 int ret;
3427 const struct lttng_kernel_type_enum *enum_type;
3428
3429 enum_type = lttng_kernel_get_type_enum(field->type);
3430 WARN_ON_ONCE(!enum_type);
3431 ret = _lttng_enum_type_statedump(session, enum_type, nesting);
3432 if (ret)
3433 return ret;
3434 return lttng_field_name_statedump(session, field, nesting);
3435 }
3436
3437 static
3438 int _lttng_integer_field_statedump(struct lttng_kernel_session *session,
3439 const struct lttng_kernel_event_field *field,
3440 size_t nesting)
3441 {
3442 int ret;
3443
3444 ret = _lttng_integer_type_statedump(session, lttng_kernel_get_type_integer(field->type),
3445 lttng_kernel_string_encoding_none, nesting);
3446 if (ret)
3447 return ret;
3448 return lttng_field_name_statedump(session, field, nesting);
3449 }
3450
3451 static
3452 int _lttng_string_type_statedump(struct lttng_kernel_session *session,
3453 const struct lttng_kernel_type_string *type,
3454 size_t nesting)
3455 {
3456 int ret;
3457
3458 /* Default encoding is UTF8 */
3459 ret = print_tabs(session, nesting);
3460 if (ret)
3461 return ret;
3462 ret = lttng_metadata_printf(session,
3463 "string%s",
3464 type->encoding == lttng_kernel_string_encoding_ASCII ?
3465 " { encoding = ASCII; }" : "");
3466 return ret;
3467 }
3468
3469 static
3470 int _lttng_string_field_statedump(struct lttng_kernel_session *session,
3471 const struct lttng_kernel_event_field *field,
3472 size_t nesting)
3473 {
3474 const struct lttng_kernel_type_string *string_type;
3475 int ret;
3476
3477 string_type = lttng_kernel_get_type_string(field->type);
3478 WARN_ON_ONCE(!string_type);
3479 ret = _lttng_string_type_statedump(session, string_type, nesting);
3480 if (ret)
3481 return ret;
3482 return lttng_field_name_statedump(session, field, nesting);
3483 }
3484
3485 /*
3486 * Must be called with sessions_mutex held.
3487 */
3488 static
3489 int _lttng_type_statedump(struct lttng_kernel_session *session,
3490 const struct lttng_kernel_type_common *type,
3491 enum lttng_kernel_string_encoding parent_encoding,
3492 size_t nesting)
3493 {
3494 int ret = 0;
3495
3496 switch (type->type) {
3497 case lttng_kernel_type_integer:
3498 ret = _lttng_integer_type_statedump(session,
3499 lttng_kernel_get_type_integer(type),
3500 parent_encoding, nesting);
3501 break;
3502 case lttng_kernel_type_enum:
3503 ret = _lttng_enum_type_statedump(session,
3504 lttng_kernel_get_type_enum(type),
3505 nesting);
3506 break;
3507 case lttng_kernel_type_string:
3508 ret = _lttng_string_type_statedump(session,
3509 lttng_kernel_get_type_string(type),
3510 nesting);
3511 break;
3512 case lttng_kernel_type_struct:
3513 ret = _lttng_struct_type_statedump(session,
3514 lttng_kernel_get_type_struct(type),
3515 nesting);
3516 break;
3517 case lttng_kernel_type_variant:
3518 ret = _lttng_variant_type_statedump(session,
3519 lttng_kernel_get_type_variant(type),
3520 nesting, NULL);
3521 break;
3522
3523 /* Nested arrays and sequences are not supported yet. */
3524 case lttng_kernel_type_array:
3525 case lttng_kernel_type_sequence:
3526 default:
3527 WARN_ON_ONCE(1);
3528 return -EINVAL;
3529 }
3530 return ret;
3531 }
3532
3533 /*
3534 * Must be called with sessions_mutex held.
3535 */
3536 static
3537 int _lttng_field_statedump(struct lttng_kernel_session *session,
3538 const struct lttng_kernel_event_field *field,
3539 size_t nesting,
3540 const char **prev_field_name_p)
3541 {
3542 const char *prev_field_name = NULL;
3543 int ret = 0;
3544
3545 if (prev_field_name_p)
3546 prev_field_name = *prev_field_name_p;
3547 switch (field->type->type) {
3548 case lttng_kernel_type_integer:
3549 ret = _lttng_integer_field_statedump(session, field, nesting);
3550 break;
3551 case lttng_kernel_type_enum:
3552 ret = _lttng_enum_field_statedump(session, field, nesting);
3553 break;
3554 case lttng_kernel_type_string:
3555 ret = _lttng_string_field_statedump(session, field, nesting);
3556 break;
3557 case lttng_kernel_type_struct:
3558 ret = _lttng_struct_field_statedump(session, field, nesting);
3559 break;
3560 case lttng_kernel_type_array:
3561 ret = _lttng_array_field_statedump(session, field, nesting);
3562 break;
3563 case lttng_kernel_type_sequence:
3564 ret = _lttng_sequence_field_statedump(session, field, nesting, prev_field_name);
3565 break;
3566 case lttng_kernel_type_variant:
3567 ret = _lttng_variant_field_statedump(session, field, nesting, prev_field_name);
3568 break;
3569
3570 default:
3571 WARN_ON_ONCE(1);
3572 return -EINVAL;
3573 }
3574 if (prev_field_name_p)
3575 *prev_field_name_p = field->name;
3576 return ret;
3577 }
3578
3579 static
3580 int _lttng_context_metadata_statedump(struct lttng_kernel_session *session,
3581 struct lttng_kernel_ctx *ctx)
3582 {
3583 const char *prev_field_name = NULL;
3584 int ret = 0;
3585 int i;
3586
3587 if (!ctx)
3588 return 0;
3589 for (i = 0; i < ctx->nr_fields; i++) {
3590 const struct lttng_kernel_ctx_field *field = &ctx->fields[i];
3591
3592 ret = _lttng_field_statedump(session, field->event_field, 2, &prev_field_name);
3593 if (ret)
3594 return ret;
3595 }
3596 return ret;
3597 }
3598
3599 static
3600 int _lttng_fields_metadata_statedump(struct lttng_kernel_session *session,
3601 struct lttng_kernel_event_recorder *event_recorder)
3602 {
3603 const char *prev_field_name = NULL;
3604 const struct lttng_kernel_event_desc *desc = event_recorder->priv->parent.desc;
3605 int ret = 0;
3606 int i;
3607
3608 for (i = 0; i < desc->tp_class->nr_fields; i++) {
3609 const struct lttng_kernel_event_field *field = desc->tp_class->fields[i];
3610
3611 ret = _lttng_field_statedump(session, field, 2, &prev_field_name);
3612 if (ret)
3613 return ret;
3614 }
3615 return ret;
3616 }
3617
3618 /*
3619 * Must be called with sessions_mutex held.
3620 * The entire event metadata is printed as a single atomic metadata
3621 * transaction.
3622 */
3623 static
3624 int _lttng_event_metadata_statedump(struct lttng_kernel_session *session,
3625 struct lttng_kernel_channel_buffer *chan,
3626 struct lttng_kernel_event_recorder *event_recorder)
3627 {
3628 int ret = 0;
3629
3630 if (event_recorder->priv->metadata_dumped || !LTTNG_READ_ONCE(session->active))
3631 return 0;
3632 if (chan->priv->channel_type == METADATA_CHANNEL)
3633 return 0;
3634
3635 lttng_metadata_begin(session);
3636
3637 ret = lttng_metadata_printf(session,
3638 "event {\n"
3639 " name = \"%s\";\n"
3640 " id = %u;\n"
3641 " stream_id = %u;\n",
3642 event_recorder->priv->parent.desc->event_name,
3643 event_recorder->priv->id,
3644 event_recorder->chan->priv->id);
3645 if (ret)
3646 goto end;
3647
3648 ret = lttng_metadata_printf(session,
3649 " fields := struct {\n"
3650 );
3651 if (ret)
3652 goto end;
3653
3654 ret = _lttng_fields_metadata_statedump(session, event_recorder);
3655 if (ret)
3656 goto end;
3657
3658 /*
3659 * LTTng space reservation can only reserve multiples of the
3660 * byte size.
3661 */
3662 ret = lttng_metadata_printf(session,
3663 " };\n"
3664 "};\n\n");
3665 if (ret)
3666 goto end;
3667
3668 event_recorder->priv->metadata_dumped = 1;
3669 end:
3670 lttng_metadata_end(session);
3671 return ret;
3672
3673 }
3674
3675 /*
3676 * Must be called with sessions_mutex held.
3677 * The entire channel metadata is printed as a single atomic metadata
3678 * transaction.
3679 */
3680 static
3681 int _lttng_channel_metadata_statedump(struct lttng_kernel_session *session,
3682 struct lttng_kernel_channel_buffer *chan)
3683 {
3684 int ret = 0;
3685
3686 if (chan->priv->metadata_dumped || !LTTNG_READ_ONCE(session->active))
3687 return 0;
3688
3689 if (chan->priv->channel_type == METADATA_CHANNEL)
3690 return 0;
3691
3692 lttng_metadata_begin(session);
3693
3694 WARN_ON_ONCE(!chan->priv->header_type);
3695 ret = lttng_metadata_printf(session,
3696 "stream {\n"
3697 " id = %u;\n"
3698 " event.header := %s;\n"
3699 " packet.context := struct packet_context;\n",
3700 chan->priv->id,
3701 chan->priv->header_type == 1 ? "struct event_header_compact" :
3702 "struct event_header_large");
3703 if (ret)
3704 goto end;
3705
3706 if (chan->priv->ctx) {
3707 ret = lttng_metadata_printf(session,
3708 " event.context := struct {\n");
3709 if (ret)
3710 goto end;
3711 }
3712 ret = _lttng_context_metadata_statedump(session, chan->priv->ctx);
3713 if (ret)
3714 goto end;
3715 if (chan->priv->ctx) {
3716 ret = lttng_metadata_printf(session,
3717 " };\n");
3718 if (ret)
3719 goto end;
3720 }
3721
3722 ret = lttng_metadata_printf(session,
3723 "};\n\n");
3724
3725 chan->priv->metadata_dumped = 1;
3726 end:
3727 lttng_metadata_end(session);
3728 return ret;
3729 }
3730
3731 /*
3732 * Must be called with sessions_mutex held.
3733 */
3734 static
3735 int _lttng_stream_packet_context_declare(struct lttng_kernel_session *session)
3736 {
3737 return lttng_metadata_printf(session,
3738 "struct packet_context {\n"
3739 " uint64_clock_monotonic_t timestamp_begin;\n"
3740 " uint64_clock_monotonic_t timestamp_end;\n"
3741 " uint64_t content_size;\n"
3742 " uint64_t packet_size;\n"
3743 " uint64_t packet_seq_num;\n"
3744 " unsigned long events_discarded;\n"
3745 " uint32_t cpu_id;\n"
3746 "};\n\n"
3747 );
3748 }
3749
3750 /*
3751 * Compact header:
3752 * id: range: 0 - 30.
3753 * id 31 is reserved to indicate an extended header.
3754 *
3755 * Large header:
3756 * id: range: 0 - 65534.
3757 * id 65535 is reserved to indicate an extended header.
3758 *
3759 * Must be called with sessions_mutex held.
3760 */
3761 static
3762 int _lttng_event_header_declare(struct lttng_kernel_session *session)
3763 {
3764 return lttng_metadata_printf(session,
3765 "struct event_header_compact {\n"
3766 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
3767 " variant <id> {\n"
3768 " struct {\n"
3769 " uint27_clock_monotonic_t timestamp;\n"
3770 " } compact;\n"
3771 " struct {\n"
3772 " uint32_t id;\n"
3773 " uint64_clock_monotonic_t timestamp;\n"
3774 " } extended;\n"
3775 " } v;\n"
3776 "} align(%u);\n"
3777 "\n"
3778 "struct event_header_large {\n"
3779 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
3780 " variant <id> {\n"
3781 " struct {\n"
3782 " uint32_clock_monotonic_t timestamp;\n"
3783 " } compact;\n"
3784 " struct {\n"
3785 " uint32_t id;\n"
3786 " uint64_clock_monotonic_t timestamp;\n"
3787 " } extended;\n"
3788 " } v;\n"
3789 "} align(%u);\n\n",
3790 lttng_alignof(uint32_t) * CHAR_BIT,
3791 lttng_alignof(uint16_t) * CHAR_BIT
3792 );
3793 }
3794
3795 /*
3796 * Approximation of NTP time of day to clock monotonic correlation,
3797 * taken at start of trace.
3798 * Yes, this is only an approximation. Yes, we can (and will) do better
3799 * in future versions.
3800 * This function may return a negative offset. It may happen if the
3801 * system sets the REALTIME clock to 0 after boot.
3802 *
3803 * Use 64bit timespec on kernels that have it, this makes 32bit arch
3804 * y2038 compliant.
3805 */
3806 static
3807 int64_t measure_clock_offset(void)
3808 {
3809 uint64_t monotonic_avg, monotonic[2], realtime;
3810 uint64_t tcf = trace_clock_freq();
3811 int64_t offset;
3812 unsigned long flags;
3813 #ifdef LTTNG_KERNEL_HAS_TIMESPEC64
3814 struct timespec64 rts = { 0, 0 };
3815 #else
3816 struct timespec rts = { 0, 0 };
3817 #endif
3818
3819 /* Disable interrupts to increase correlation precision. */
3820 local_irq_save(flags);
3821 monotonic[0] = trace_clock_read64();
3822 #ifdef LTTNG_KERNEL_HAS_TIMESPEC64
3823 ktime_get_real_ts64(&rts);
3824 #else
3825 getnstimeofday(&rts);
3826 #endif
3827 monotonic[1] = trace_clock_read64();
3828 local_irq_restore(flags);
3829
3830 monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
3831 realtime = (uint64_t) rts.tv_sec * tcf;
3832 if (tcf == NSEC_PER_SEC) {
3833 realtime += rts.tv_nsec;
3834 } else {
3835 uint64_t n = rts.tv_nsec * tcf;
3836
3837 do_div(n, NSEC_PER_SEC);
3838 realtime += n;
3839 }
3840 offset = (int64_t) realtime - monotonic_avg;
3841 return offset;
3842 }
3843
3844 static
3845 int print_escaped_ctf_string(struct lttng_kernel_session *session, const char *string)
3846 {
3847 int ret = 0;
3848 size_t i;
3849 char cur;
3850
3851 i = 0;
3852 cur = string[i];
3853 while (cur != '\0') {
3854 switch (cur) {
3855 case '\n':
3856 ret = lttng_metadata_printf(session, "%s", "\\n");
3857 break;
3858 case '\\':
3859 case '"':
3860 ret = lttng_metadata_printf(session, "%c", '\\');
3861 if (ret)
3862 goto error;
3863 /* We still print the current char */
3864 lttng_fallthrough;
3865 default:
3866 ret = lttng_metadata_printf(session, "%c", cur);
3867 break;
3868 }
3869
3870 if (ret)
3871 goto error;
3872
3873 cur = string[++i];
3874 }
3875 error:
3876 return ret;
3877 }
3878
3879 static
3880 int print_metadata_escaped_field(struct lttng_kernel_session *session, const char *field,
3881 const char *field_value)
3882 {
3883 int ret;
3884
3885 ret = lttng_metadata_printf(session, " %s = \"", field);
3886 if (ret)
3887 goto error;
3888
3889 ret = print_escaped_ctf_string(session, field_value);
3890 if (ret)
3891 goto error;
3892
3893 ret = lttng_metadata_printf(session, "\";\n");
3894
3895 error:
3896 return ret;
3897 }
3898
3899 /*
3900 * Output metadata into this session's metadata buffers.
3901 * Must be called with sessions_mutex held.
3902 */
3903 static
3904 int _lttng_session_metadata_statedump(struct lttng_kernel_session *session)
3905 {
3906 unsigned char *uuid_c = session->priv->uuid.b;
3907 unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN];
3908 const char *product_uuid;
3909 struct lttng_kernel_channel_buffer_private *chan_priv;
3910 struct lttng_kernel_event_recorder_private *event_recorder_priv;
3911 int ret = 0;
3912
3913 if (!LTTNG_READ_ONCE(session->active))
3914 return 0;
3915
3916 lttng_metadata_begin(session);
3917
3918 if (session->priv->metadata_dumped)
3919 goto skip_session;
3920
3921 snprintf(uuid_s, sizeof(uuid_s),
3922 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
3923 uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3],
3924 uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7],
3925 uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11],
3926 uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]);
3927
3928 ret = lttng_metadata_printf(session,
3929 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
3930 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
3931 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
3932 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
3933 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
3934 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
3935 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
3936 "\n"
3937 "trace {\n"
3938 " major = %u;\n"
3939 " minor = %u;\n"
3940 " uuid = \"%s\";\n"
3941 " byte_order = %s;\n"
3942 " packet.header := struct {\n"
3943 " uint32_t magic;\n"
3944 " uint8_t uuid[16];\n"
3945 " uint32_t stream_id;\n"
3946 " uint64_t stream_instance_id;\n"
3947 " };\n"
3948 "};\n\n",
3949 lttng_alignof(uint8_t) * CHAR_BIT,
3950 lttng_alignof(uint16_t) * CHAR_BIT,
3951 lttng_alignof(uint32_t) * CHAR_BIT,
3952 lttng_alignof(uint64_t) * CHAR_BIT,
3953 sizeof(unsigned long) * CHAR_BIT,
3954 lttng_alignof(unsigned long) * CHAR_BIT,
3955 CTF_SPEC_MAJOR,
3956 CTF_SPEC_MINOR,
3957 uuid_s,
3958 #if __BYTE_ORDER == __BIG_ENDIAN
3959 "be"
3960 #else
3961 "le"
3962 #endif
3963 );
3964 if (ret)
3965 goto end;
3966
3967 ret = lttng_metadata_printf(session,
3968 "env {\n"
3969 " hostname = \"%s\";\n"
3970 " domain = \"kernel\";\n"
3971 " sysname = \"%s\";\n"
3972 " kernel_release = \"%s\";\n"
3973 " kernel_version = \"%s\";\n"
3974 " tracer_name = \"lttng-modules\";\n"
3975 " tracer_major = %d;\n"
3976 " tracer_minor = %d;\n"
3977 " tracer_patchlevel = %d;\n"
3978 " trace_buffering_scheme = \"global\";\n",
3979 current->nsproxy->uts_ns->name.nodename,
3980 utsname()->sysname,
3981 utsname()->release,
3982 utsname()->version,
3983 LTTNG_MODULES_MAJOR_VERSION,
3984 LTTNG_MODULES_MINOR_VERSION,
3985 LTTNG_MODULES_PATCHLEVEL_VERSION
3986 );
3987 if (ret)
3988 goto end;
3989
3990 ret = print_metadata_escaped_field(session, "trace_name", session->priv->name);
3991 if (ret)
3992 goto end;
3993 ret = print_metadata_escaped_field(session, "trace_creation_datetime",
3994 session->priv->creation_time);
3995 if (ret)
3996 goto end;
3997
3998 /* Add the product UUID to the 'env' section */
3999 product_uuid = dmi_get_system_info(DMI_PRODUCT_UUID);
4000 if (product_uuid) {
4001 ret = lttng_metadata_printf(session,
4002 " product_uuid = \"%s\";\n",
4003 product_uuid
4004 );
4005 if (ret)
4006 goto end;
4007 }
4008
4009 /* Close the 'env' section */
4010 ret = lttng_metadata_printf(session, "};\n\n");
4011 if (ret)
4012 goto end;
4013
4014 ret = lttng_metadata_printf(session,
4015 "clock {\n"
4016 " name = \"%s\";\n",
4017 trace_clock_name()
4018 );
4019 if (ret)
4020 goto end;
4021
4022 if (!trace_clock_uuid(clock_uuid_s)) {
4023 ret = lttng_metadata_printf(session,
4024 " uuid = \"%s\";\n",
4025 clock_uuid_s
4026 );
4027 if (ret)
4028 goto end;
4029 }
4030
4031 ret = lttng_metadata_printf(session,
4032 " description = \"%s\";\n"
4033 " freq = %llu; /* Frequency, in Hz */\n"
4034 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
4035 " offset = %lld;\n"
4036 "};\n\n",
4037 trace_clock_description(),
4038 (unsigned long long) trace_clock_freq(),
4039 (long long) measure_clock_offset()
4040 );
4041 if (ret)
4042 goto end;
4043
4044 ret = lttng_metadata_printf(session,
4045 "typealias integer {\n"
4046 " size = 27; align = 1; signed = false;\n"
4047 " map = clock.%s.value;\n"
4048 "} := uint27_clock_monotonic_t;\n"
4049 "\n"
4050 "typealias integer {\n"
4051 " size = 32; align = %u; signed = false;\n"
4052 " map = clock.%s.value;\n"
4053 "} := uint32_clock_monotonic_t;\n"
4054 "\n"
4055 "typealias integer {\n"
4056 " size = 64; align = %u; signed = false;\n"
4057 " map = clock.%s.value;\n"
4058 "} := uint64_clock_monotonic_t;\n\n",
4059 trace_clock_name(),
4060 lttng_alignof(uint32_t) * CHAR_BIT,
4061 trace_clock_name(),
4062 lttng_alignof(uint64_t) * CHAR_BIT,
4063 trace_clock_name()
4064 );
4065 if (ret)
4066 goto end;
4067
4068 ret = _lttng_stream_packet_context_declare(session);
4069 if (ret)
4070 goto end;
4071
4072 ret = _lttng_event_header_declare(session);
4073 if (ret)
4074 goto end;
4075
4076 skip_session:
4077 list_for_each_entry(chan_priv, &session->priv->chan, node) {
4078 ret = _lttng_channel_metadata_statedump(session, chan_priv->pub);
4079 if (ret)
4080 goto end;
4081 }
4082
4083 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
4084 ret = _lttng_event_metadata_statedump(session, event_recorder_priv->pub->chan,
4085 event_recorder_priv->pub);
4086 if (ret)
4087 goto end;
4088 }
4089 session->priv->metadata_dumped = 1;
4090 end:
4091 lttng_metadata_end(session);
4092 return ret;
4093 }
4094
4095 /**
4096 * lttng_transport_register - LTT transport registration
4097 * @transport: transport structure
4098 *
4099 * Registers a transport which can be used as output to extract the data out of
4100 * LTTng. The module calling this registration function must ensure that no
4101 * trap-inducing code will be executed by the transport functions. E.g.
4102 * vmalloc_sync_mappings() must be called between a vmalloc and the moment the memory
4103 * is made visible to the transport function. This registration acts as a
4104 * vmalloc_sync_mappings. Therefore, only if the module allocates virtual memory
4105 * after its registration must it synchronize the TLBs.
4106 */
4107 void lttng_transport_register(struct lttng_transport *transport)
4108 {
4109 /*
4110 * Make sure no page fault can be triggered by the module about to be
4111 * registered. We deal with this here so we don't have to call
4112 * vmalloc_sync_mappings() in each module's init.
4113 */
4114 wrapper_vmalloc_sync_mappings();
4115
4116 mutex_lock(&sessions_mutex);
4117 list_add_tail(&transport->node, &lttng_transport_list);
4118 mutex_unlock(&sessions_mutex);
4119 }
4120 EXPORT_SYMBOL_GPL(lttng_transport_register);
4121
4122 /**
4123 * lttng_transport_unregister - LTT transport unregistration
4124 * @transport: transport structure
4125 */
4126 void lttng_transport_unregister(struct lttng_transport *transport)
4127 {
4128 mutex_lock(&sessions_mutex);
4129 list_del(&transport->node);
4130 mutex_unlock(&sessions_mutex);
4131 }
4132 EXPORT_SYMBOL_GPL(lttng_transport_unregister);
4133
4134 void lttng_counter_transport_register(struct lttng_counter_transport *transport)
4135 {
4136 /*
4137 * Make sure no page fault can be triggered by the module about to be
4138 * registered. We deal with this here so we don't have to call
4139 * vmalloc_sync_mappings() in each module's init.
4140 */
4141 wrapper_vmalloc_sync_mappings();
4142
4143 mutex_lock(&sessions_mutex);
4144 list_add_tail(&transport->node, &lttng_counter_transport_list);
4145 mutex_unlock(&sessions_mutex);
4146 }
4147 EXPORT_SYMBOL_GPL(lttng_counter_transport_register);
4148
4149 void lttng_counter_transport_unregister(struct lttng_counter_transport *transport)
4150 {
4151 mutex_lock(&sessions_mutex);
4152 list_del(&transport->node);
4153 mutex_unlock(&sessions_mutex);
4154 }
4155 EXPORT_SYMBOL_GPL(lttng_counter_transport_unregister);
4156
4157 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0))
4158
4159 enum cpuhp_state lttng_hp_prepare;
4160 enum cpuhp_state lttng_hp_online;
4161
4162 static int lttng_hotplug_prepare(unsigned int cpu, struct hlist_node *node)
4163 {
4164 struct lttng_cpuhp_node *lttng_node;
4165
4166 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4167 switch (lttng_node->component) {
4168 case LTTNG_RING_BUFFER_FRONTEND:
4169 return 0;
4170 case LTTNG_RING_BUFFER_BACKEND:
4171 return lttng_cpuhp_rb_backend_prepare(cpu, lttng_node);
4172 case LTTNG_RING_BUFFER_ITER:
4173 return 0;
4174 case LTTNG_CONTEXT_PERF_COUNTERS:
4175 return 0;
4176 default:
4177 return -EINVAL;
4178 }
4179 }
4180
4181 static int lttng_hotplug_dead(unsigned int cpu, struct hlist_node *node)
4182 {
4183 struct lttng_cpuhp_node *lttng_node;
4184
4185 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4186 switch (lttng_node->component) {
4187 case LTTNG_RING_BUFFER_FRONTEND:
4188 return lttng_cpuhp_rb_frontend_dead(cpu, lttng_node);
4189 case LTTNG_RING_BUFFER_BACKEND:
4190 return 0;
4191 case LTTNG_RING_BUFFER_ITER:
4192 return 0;
4193 case LTTNG_CONTEXT_PERF_COUNTERS:
4194 return lttng_cpuhp_perf_counter_dead(cpu, lttng_node);
4195 default:
4196 return -EINVAL;
4197 }
4198 }
4199
4200 static int lttng_hotplug_online(unsigned int cpu, struct hlist_node *node)
4201 {
4202 struct lttng_cpuhp_node *lttng_node;
4203
4204 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4205 switch (lttng_node->component) {
4206 case LTTNG_RING_BUFFER_FRONTEND:
4207 return lttng_cpuhp_rb_frontend_online(cpu, lttng_node);
4208 case LTTNG_RING_BUFFER_BACKEND:
4209 return 0;
4210 case LTTNG_RING_BUFFER_ITER:
4211 return lttng_cpuhp_rb_iter_online(cpu, lttng_node);
4212 case LTTNG_CONTEXT_PERF_COUNTERS:
4213 return lttng_cpuhp_perf_counter_online(cpu, lttng_node);
4214 default:
4215 return -EINVAL;
4216 }
4217 }
4218
4219 static int lttng_hotplug_offline(unsigned int cpu, struct hlist_node *node)
4220 {
4221 struct lttng_cpuhp_node *lttng_node;
4222
4223 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4224 switch (lttng_node->component) {
4225 case LTTNG_RING_BUFFER_FRONTEND:
4226 return lttng_cpuhp_rb_frontend_offline(cpu, lttng_node);
4227 case LTTNG_RING_BUFFER_BACKEND:
4228 return 0;
4229 case LTTNG_RING_BUFFER_ITER:
4230 return 0;
4231 case LTTNG_CONTEXT_PERF_COUNTERS:
4232 return 0;
4233 default:
4234 return -EINVAL;
4235 }
4236 }
4237
4238 static int __init lttng_init_cpu_hotplug(void)
4239 {
4240 int ret;
4241
4242 ret = cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN, "lttng:prepare",
4243 lttng_hotplug_prepare,
4244 lttng_hotplug_dead);
4245 if (ret < 0) {
4246 return ret;
4247 }
4248 lttng_hp_prepare = ret;
4249 lttng_rb_set_hp_prepare(ret);
4250
4251 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "lttng:online",
4252 lttng_hotplug_online,
4253 lttng_hotplug_offline);
4254 if (ret < 0) {
4255 cpuhp_remove_multi_state(lttng_hp_prepare);
4256 lttng_hp_prepare = 0;
4257 return ret;
4258 }
4259 lttng_hp_online = ret;
4260 lttng_rb_set_hp_online(ret);
4261
4262 return 0;
4263 }
4264
4265 static void __exit lttng_exit_cpu_hotplug(void)
4266 {
4267 lttng_rb_set_hp_online(0);
4268 cpuhp_remove_multi_state(lttng_hp_online);
4269 lttng_rb_set_hp_prepare(0);
4270 cpuhp_remove_multi_state(lttng_hp_prepare);
4271 }
4272
4273 #else /* #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
4274 static int lttng_init_cpu_hotplug(void)
4275 {
4276 return 0;
4277 }
4278 static void lttng_exit_cpu_hotplug(void)
4279 {
4280 }
4281 #endif /* #else #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
4282
4283 static int __init lttng_events_init(void)
4284 {
4285 int ret;
4286
4287 ret = wrapper_lttng_fixup_sig(THIS_MODULE);
4288 if (ret)
4289 return ret;
4290 ret = wrapper_get_pfnblock_flags_mask_init();
4291 if (ret)
4292 return ret;
4293 ret = wrapper_get_pageblock_flags_mask_init();
4294 if (ret)
4295 return ret;
4296 ret = lttng_probes_init();
4297 if (ret)
4298 return ret;
4299 ret = lttng_context_init();
4300 if (ret)
4301 return ret;
4302 ret = lttng_tracepoint_init();
4303 if (ret)
4304 goto error_tp;
4305 event_recorder_cache = KMEM_CACHE(lttng_kernel_event_recorder, 0);
4306 if (!event_recorder_cache) {
4307 ret = -ENOMEM;
4308 goto error_kmem_event_recorder;
4309 }
4310 event_recorder_private_cache = KMEM_CACHE(lttng_kernel_event_recorder_private, 0);
4311 if (!event_recorder_private_cache) {
4312 ret = -ENOMEM;
4313 goto error_kmem_event_recorder_private;
4314 }
4315 event_notifier_cache = KMEM_CACHE(lttng_kernel_event_notifier, 0);
4316 if (!event_notifier_cache) {
4317 ret = -ENOMEM;
4318 goto error_kmem_event_notifier;
4319 }
4320 event_notifier_private_cache = KMEM_CACHE(lttng_kernel_event_notifier_private, 0);
4321 if (!event_notifier_private_cache) {
4322 ret = -ENOMEM;
4323 goto error_kmem_event_notifier_private;
4324 }
4325 ret = lttng_abi_init();
4326 if (ret)
4327 goto error_abi;
4328 ret = lttng_logger_init();
4329 if (ret)
4330 goto error_logger;
4331 ret = lttng_init_cpu_hotplug();
4332 if (ret)
4333 goto error_hotplug;
4334 printk(KERN_NOTICE "LTTng: Loaded modules v%s.%s.%s%s (%s)%s%s\n",
4335 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4336 __stringify(LTTNG_MODULES_MINOR_VERSION),
4337 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4338 LTTNG_MODULES_EXTRAVERSION,
4339 LTTNG_VERSION_NAME,
4340 #ifdef LTTNG_EXTRA_VERSION_GIT
4341 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4342 #else
4343 "",
4344 #endif
4345 #ifdef LTTNG_EXTRA_VERSION_NAME
4346 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4347 #else
4348 "");
4349 #endif
4350 #ifdef CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM
4351 printk(KERN_NOTICE "LTTng: Experimental bitwise enum enabled.\n");
4352 #endif /* CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM */
4353 return 0;
4354
4355 error_hotplug:
4356 lttng_logger_exit();
4357 error_logger:
4358 lttng_abi_exit();
4359 error_abi:
4360 kmem_cache_destroy(event_notifier_private_cache);
4361 error_kmem_event_notifier_private:
4362 kmem_cache_destroy(event_notifier_cache);
4363 error_kmem_event_notifier:
4364 kmem_cache_destroy(event_recorder_private_cache);
4365 error_kmem_event_recorder_private:
4366 kmem_cache_destroy(event_recorder_cache);
4367 error_kmem_event_recorder:
4368 lttng_tracepoint_exit();
4369 error_tp:
4370 lttng_context_exit();
4371 printk(KERN_NOTICE "LTTng: Failed to load modules v%s.%s.%s%s (%s)%s%s\n",
4372 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4373 __stringify(LTTNG_MODULES_MINOR_VERSION),
4374 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4375 LTTNG_MODULES_EXTRAVERSION,
4376 LTTNG_VERSION_NAME,
4377 #ifdef LTTNG_EXTRA_VERSION_GIT
4378 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4379 #else
4380 "",
4381 #endif
4382 #ifdef LTTNG_EXTRA_VERSION_NAME
4383 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4384 #else
4385 "");
4386 #endif
4387 return ret;
4388 }
4389
4390 module_init(lttng_events_init);
4391
4392 static void __exit lttng_events_exit(void)
4393 {
4394 struct lttng_kernel_session_private *session_priv, *tmpsession_priv;
4395
4396 lttng_exit_cpu_hotplug();
4397 lttng_logger_exit();
4398 lttng_abi_exit();
4399 list_for_each_entry_safe(session_priv, tmpsession_priv, &sessions, list)
4400 lttng_session_destroy(session_priv->pub);
4401 kmem_cache_destroy(event_recorder_cache);
4402 kmem_cache_destroy(event_recorder_private_cache);
4403 kmem_cache_destroy(event_notifier_cache);
4404 kmem_cache_destroy(event_notifier_private_cache);
4405 lttng_tracepoint_exit();
4406 lttng_context_exit();
4407 printk(KERN_NOTICE "LTTng: Unloaded modules v%s.%s.%s%s (%s)%s%s\n",
4408 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4409 __stringify(LTTNG_MODULES_MINOR_VERSION),
4410 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4411 LTTNG_MODULES_EXTRAVERSION,
4412 LTTNG_VERSION_NAME,
4413 #ifdef LTTNG_EXTRA_VERSION_GIT
4414 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4415 #else
4416 "",
4417 #endif
4418 #ifdef LTTNG_EXTRA_VERSION_NAME
4419 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4420 #else
4421 "");
4422 #endif
4423 }
4424
4425 module_exit(lttng_events_exit);
4426
4427 #include <generated/patches.h>
4428 #ifdef LTTNG_EXTRA_VERSION_GIT
4429 MODULE_INFO(extra_version_git, LTTNG_EXTRA_VERSION_GIT);
4430 #endif
4431 #ifdef LTTNG_EXTRA_VERSION_NAME
4432 MODULE_INFO(extra_version_name, LTTNG_EXTRA_VERSION_NAME);
4433 #endif
4434 MODULE_LICENSE("GPL and additional rights");
4435 MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
4436 MODULE_DESCRIPTION("LTTng tracer");
4437 MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
4438 __stringify(LTTNG_MODULES_MINOR_VERSION) "."
4439 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
4440 LTTNG_MODULES_EXTRAVERSION);
LTTng 2.0/0.x modules
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