projects / lttng-modules.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
fix: adjust ranges for RHEL 8.2 and 8.3
[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/uuid.h>
32 #include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
33 #include <wrapper/random.h>
34 #include <wrapper/tracepoint.h>
35 #include <wrapper/list.h>
36 #include <wrapper/types.h>
37 #include <lttng/kernel-version.h>
38 #include <lttng/events.h>
39 #include <lttng/events-internal.h>
40 #include <lttng/lttng-bytecode.h>
41 #include <lttng/tracer.h>
42 #include <lttng/event-notifier-notification.h>
43 #include <lttng/abi-old.h>
44 #include <lttng/endian.h>
45 #include <lttng/string-utils.h>
46 #include <lttng/utils.h>
47 #include <ringbuffer/backend.h>
48 #include <ringbuffer/frontend.h>
49 #include <wrapper/time.h>
50
51 #define METADATA_CACHE_DEFAULT_SIZE 4096
52
53 static LIST_HEAD(sessions);
54 static LIST_HEAD(event_notifier_groups);
55 static LIST_HEAD(lttng_transport_list);
56 static LIST_HEAD(lttng_counter_transport_list);
57 /*
58 * Protect the sessions and metadata caches.
59 */
60 static DEFINE_MUTEX(sessions_mutex);
61 static struct kmem_cache *event_recorder_cache;
62 static struct kmem_cache *event_recorder_private_cache;
63 static struct kmem_cache *event_notifier_cache;
64 static struct kmem_cache *event_notifier_private_cache;
65
66 static void lttng_session_lazy_sync_event_enablers(struct lttng_kernel_session *session);
67 static void lttng_session_sync_event_enablers(struct lttng_kernel_session *session);
68 static void lttng_event_enabler_destroy(struct lttng_event_enabler *event_enabler);
69 static void lttng_event_notifier_enabler_destroy(struct lttng_event_notifier_enabler *event_notifier_enabler);
70 static void lttng_event_notifier_group_sync_enablers(struct lttng_event_notifier_group *event_notifier_group);
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_recorder *event);
75 static int _lttng_event_notifier_unregister(struct lttng_kernel_event_notifier *event_notifier);
76 static
77 int _lttng_event_metadata_statedump(struct lttng_kernel_session *session,
78 struct lttng_kernel_channel_buffer *chan,
79 struct lttng_kernel_event_recorder *event);
80 static
81 int _lttng_session_metadata_statedump(struct lttng_kernel_session *session);
82 static
83 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream);
84 static
85 int _lttng_type_statedump(struct lttng_kernel_session *session,
86 const struct lttng_kernel_type_common *type,
87 enum lttng_kernel_string_encoding parent_encoding,
88 size_t nesting);
89 static
90 int _lttng_field_statedump(struct lttng_kernel_session *session,
91 const struct lttng_kernel_event_field *field,
92 size_t nesting, const char **prev_field_name_p);
93
94 void synchronize_trace(void)
95 {
96 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(5,1,0) || \
97 LTTNG_RHEL_KERNEL_RANGE(4,18,0,193,0,0, 4,19,0,0,0,0))
98 synchronize_rcu();
99 #else
100 synchronize_sched();
101 #endif
102
103 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0))
104 #ifdef CONFIG_PREEMPT_RT_FULL
105 synchronize_rcu();
106 #endif
107 #else /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
108 #ifdef CONFIG_PREEMPT_RT
109 synchronize_rcu();
110 #endif
111 #endif /* (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(3,4,0)) */
112 }
113
114 void lttng_lock_sessions(void)
115 {
116 mutex_lock(&sessions_mutex);
117 }
118
119 void lttng_unlock_sessions(void)
120 {
121 mutex_unlock(&sessions_mutex);
122 }
123
124 static struct lttng_transport *lttng_transport_find(const char *name)
125 {
126 struct lttng_transport *transport;
127
128 list_for_each_entry(transport, &lttng_transport_list, node) {
129 if (!strcmp(transport->name, name))
130 return transport;
131 }
132 return NULL;
133 }
134
135 /*
136 * Called with sessions lock held.
137 */
138 int lttng_session_active(void)
139 {
140 struct lttng_kernel_session_private *iter;
141
142 list_for_each_entry(iter, &sessions, list) {
143 if (iter->pub->active)
144 return 1;
145 }
146 return 0;
147 }
148
149 struct lttng_kernel_session *lttng_session_create(void)
150 {
151 struct lttng_kernel_session *session;
152 struct lttng_kernel_session_private *session_priv;
153 struct lttng_metadata_cache *metadata_cache;
154 int i;
155
156 mutex_lock(&sessions_mutex);
157 session = lttng_kvzalloc(sizeof(*session), GFP_KERNEL);
158 if (!session)
159 goto err;
160 session_priv = lttng_kvzalloc(sizeof(*session_priv), GFP_KERNEL);
161 if (!session_priv)
162 goto err_free_session;
163 session->priv = session_priv;
164 session_priv->pub = session;
165
166 INIT_LIST_HEAD(&session_priv->chan);
167 INIT_LIST_HEAD(&session_priv->events);
168 lttng_guid_gen(&session_priv->uuid);
169
170 metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache),
171 GFP_KERNEL);
172 if (!metadata_cache)
173 goto err_free_session_private;
174 metadata_cache->data = vzalloc(METADATA_CACHE_DEFAULT_SIZE);
175 if (!metadata_cache->data)
176 goto err_free_cache;
177 metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE;
178 kref_init(&metadata_cache->refcount);
179 mutex_init(&metadata_cache->lock);
180 session_priv->metadata_cache = metadata_cache;
181 INIT_LIST_HEAD(&metadata_cache->metadata_stream);
182 memcpy(&metadata_cache->uuid, &session_priv->uuid,
183 sizeof(metadata_cache->uuid));
184 INIT_LIST_HEAD(&session_priv->enablers_head);
185 for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
186 INIT_HLIST_HEAD(&session_priv->events_ht.table[i]);
187 list_add(&session_priv->list, &sessions);
188
189 if (lttng_id_tracker_init(&session->pid_tracker, session, TRACKER_PID))
190 goto tracker_alloc_error;
191 if (lttng_id_tracker_init(&session->vpid_tracker, session, TRACKER_VPID))
192 goto tracker_alloc_error;
193 if (lttng_id_tracker_init(&session->uid_tracker, session, TRACKER_UID))
194 goto tracker_alloc_error;
195 if (lttng_id_tracker_init(&session->vuid_tracker, session, TRACKER_VUID))
196 goto tracker_alloc_error;
197 if (lttng_id_tracker_init(&session->gid_tracker, session, TRACKER_GID))
198 goto tracker_alloc_error;
199 if (lttng_id_tracker_init(&session->vgid_tracker, session, TRACKER_VGID))
200 goto tracker_alloc_error;
201
202 mutex_unlock(&sessions_mutex);
203
204 return session;
205
206 tracker_alloc_error:
207 lttng_id_tracker_fini(&session->pid_tracker);
208 lttng_id_tracker_fini(&session->vpid_tracker);
209 lttng_id_tracker_fini(&session->uid_tracker);
210 lttng_id_tracker_fini(&session->vuid_tracker);
211 lttng_id_tracker_fini(&session->gid_tracker);
212 lttng_id_tracker_fini(&session->vgid_tracker);
213 err_free_cache:
214 kfree(metadata_cache);
215 err_free_session_private:
216 lttng_kvfree(session_priv);
217 err_free_session:
218 lttng_kvfree(session);
219 err:
220 mutex_unlock(&sessions_mutex);
221 return NULL;
222 }
223
224 static
225 struct lttng_counter_transport *lttng_counter_transport_find(const char *name)
226 {
227 struct lttng_counter_transport *transport;
228
229 list_for_each_entry(transport, &lttng_counter_transport_list, node) {
230 if (!strcmp(transport->name, name))
231 return transport;
232 }
233 return NULL;
234 }
235
236 struct lttng_counter *lttng_kernel_counter_create(
237 const char *counter_transport_name,
238 size_t number_dimensions, const size_t *dimensions_sizes)
239 {
240 struct lttng_counter *counter = NULL;
241 struct lttng_counter_transport *counter_transport = NULL;
242
243 counter_transport = lttng_counter_transport_find(counter_transport_name);
244 if (!counter_transport) {
245 printk(KERN_WARNING "LTTng: counter transport %s not found.\n",
246 counter_transport_name);
247 goto notransport;
248 }
249 if (!try_module_get(counter_transport->owner)) {
250 printk(KERN_WARNING "LTTng: Can't lock counter transport module.\n");
251 goto notransport;
252 }
253
254 counter = lttng_kvzalloc(sizeof(struct lttng_counter), GFP_KERNEL);
255 if (!counter)
256 goto nomem;
257
258 /* Create event notifier error counter. */
259 counter->ops = &counter_transport->ops;
260 counter->transport = counter_transport;
261
262 counter->counter = counter->ops->counter_create(
263 number_dimensions, dimensions_sizes, 0);
264 if (!counter->counter) {
265 goto create_error;
266 }
267
268 return counter;
269
270 create_error:
271 lttng_kvfree(counter);
272 nomem:
273 if (counter_transport)
274 module_put(counter_transport->owner);
275 notransport:
276 return NULL;
277 }
278
279 struct lttng_event_notifier_group *lttng_event_notifier_group_create(void)
280 {
281 struct lttng_transport *transport = NULL;
282 struct lttng_event_notifier_group *event_notifier_group;
283 const char *transport_name = "relay-event-notifier";
284 size_t subbuf_size = 4096; //TODO
285 size_t num_subbuf = 16; //TODO
286 unsigned int switch_timer_interval = 0;
287 unsigned int read_timer_interval = 0;
288 int i;
289
290 mutex_lock(&sessions_mutex);
291
292 transport = lttng_transport_find(transport_name);
293 if (!transport) {
294 printk(KERN_WARNING "LTTng: transport %s not found\n",
295 transport_name);
296 goto notransport;
297 }
298 if (!try_module_get(transport->owner)) {
299 printk(KERN_WARNING "LTTng: Can't lock transport %s module.\n",
300 transport_name);
301 goto notransport;
302 }
303
304 event_notifier_group = lttng_kvzalloc(sizeof(struct lttng_event_notifier_group),
305 GFP_KERNEL);
306 if (!event_notifier_group)
307 goto nomem;
308
309 /*
310 * Initialize the ring buffer used to store event notifier
311 * notifications.
312 */
313 event_notifier_group->ops = &transport->ops;
314 event_notifier_group->chan = transport->ops.priv->channel_create(
315 transport_name, event_notifier_group, NULL,
316 subbuf_size, num_subbuf, switch_timer_interval,
317 read_timer_interval);
318 if (!event_notifier_group->chan)
319 goto create_error;
320
321 event_notifier_group->transport = transport;
322
323 INIT_LIST_HEAD(&event_notifier_group->enablers_head);
324 INIT_LIST_HEAD(&event_notifier_group->event_notifiers_head);
325 for (i = 0; i < LTTNG_EVENT_NOTIFIER_HT_SIZE; i++)
326 INIT_HLIST_HEAD(&event_notifier_group->event_notifiers_ht.table[i]);
327
328 list_add(&event_notifier_group->node, &event_notifier_groups);
329
330 mutex_unlock(&sessions_mutex);
331
332 return event_notifier_group;
333
334 create_error:
335 lttng_kvfree(event_notifier_group);
336 nomem:
337 if (transport)
338 module_put(transport->owner);
339 notransport:
340 mutex_unlock(&sessions_mutex);
341 return NULL;
342 }
343
344 void metadata_cache_destroy(struct kref *kref)
345 {
346 struct lttng_metadata_cache *cache =
347 container_of(kref, struct lttng_metadata_cache, refcount);
348 vfree(cache->data);
349 kfree(cache);
350 }
351
352 void lttng_session_destroy(struct lttng_kernel_session *session)
353 {
354 struct lttng_kernel_channel_buffer_private *chan_priv, *tmpchan_priv;
355 struct lttng_kernel_event_recorder_private *event_recorder_priv, *tmpevent_recorder_priv;
356 struct lttng_metadata_stream *metadata_stream;
357 struct lttng_event_enabler *event_enabler, *tmp_event_enabler;
358 int ret;
359
360 mutex_lock(&sessions_mutex);
361 WRITE_ONCE(session->active, 0);
362 list_for_each_entry(chan_priv, &session->priv->chan, node) {
363 ret = lttng_syscalls_unregister_channel(chan_priv->pub);
364 WARN_ON(ret);
365 }
366 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
367 ret = _lttng_event_unregister(event_recorder_priv->pub);
368 WARN_ON(ret);
369 }
370 synchronize_trace(); /* Wait for in-flight events to complete */
371 list_for_each_entry(chan_priv, &session->priv->chan, node) {
372 ret = lttng_syscalls_destroy_event(chan_priv->pub);
373 WARN_ON(ret);
374 }
375 list_for_each_entry_safe(event_enabler, tmp_event_enabler,
376 &session->priv->enablers_head, node)
377 lttng_event_enabler_destroy(event_enabler);
378 list_for_each_entry_safe(event_recorder_priv, tmpevent_recorder_priv, &session->priv->events, node)
379 _lttng_event_destroy(&event_recorder_priv->pub->parent);
380 list_for_each_entry_safe(chan_priv, tmpchan_priv, &session->priv->chan, node) {
381 BUG_ON(chan_priv->channel_type == METADATA_CHANNEL);
382 _lttng_channel_destroy(chan_priv->pub);
383 }
384 mutex_lock(&session->priv->metadata_cache->lock);
385 list_for_each_entry(metadata_stream, &session->priv->metadata_cache->metadata_stream, list)
386 _lttng_metadata_channel_hangup(metadata_stream);
387 mutex_unlock(&session->priv->metadata_cache->lock);
388 lttng_id_tracker_fini(&session->pid_tracker);
389 lttng_id_tracker_fini(&session->vpid_tracker);
390 lttng_id_tracker_fini(&session->uid_tracker);
391 lttng_id_tracker_fini(&session->vuid_tracker);
392 lttng_id_tracker_fini(&session->gid_tracker);
393 lttng_id_tracker_fini(&session->vgid_tracker);
394 kref_put(&session->priv->metadata_cache->refcount, metadata_cache_destroy);
395 list_del(&session->priv->list);
396 mutex_unlock(&sessions_mutex);
397 lttng_kvfree(session->priv);
398 lttng_kvfree(session);
399 }
400
401 void lttng_event_notifier_group_destroy(
402 struct lttng_event_notifier_group *event_notifier_group)
403 {
404 struct lttng_event_notifier_enabler *event_notifier_enabler, *tmp_event_notifier_enabler;
405 struct lttng_kernel_event_notifier_private *event_notifier_priv, *tmpevent_notifier_priv;
406 int ret;
407
408 if (!event_notifier_group)
409 return;
410
411 mutex_lock(&sessions_mutex);
412
413 ret = lttng_syscalls_unregister_event_notifier_group(event_notifier_group);
414 WARN_ON(ret);
415
416 list_for_each_entry_safe(event_notifier_priv, tmpevent_notifier_priv,
417 &event_notifier_group->event_notifiers_head, node) {
418 ret = _lttng_event_notifier_unregister(event_notifier_priv->pub);
419 WARN_ON(ret);
420 }
421
422 /* Wait for in-flight event notifier to complete */
423 synchronize_trace();
424
425 irq_work_sync(&event_notifier_group->wakeup_pending);
426
427 kfree(event_notifier_group->sc_filter);
428
429 list_for_each_entry_safe(event_notifier_enabler, tmp_event_notifier_enabler,
430 &event_notifier_group->enablers_head, node)
431 lttng_event_notifier_enabler_destroy(event_notifier_enabler);
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 int lttng_channel_enable(struct lttng_kernel_channel_buffer *channel)
582 {
583 int ret = 0;
584
585 mutex_lock(&sessions_mutex);
586 if (channel->priv->channel_type == METADATA_CHANNEL) {
587 ret = -EPERM;
588 goto end;
589 }
590 if (channel->parent.enabled) {
591 ret = -EEXIST;
592 goto end;
593 }
594 /* Set transient enabler state to "enabled" */
595 channel->priv->parent.tstate = 1;
596 lttng_session_sync_event_enablers(channel->parent.session);
597 /* Set atomically the state to "enabled" */
598 WRITE_ONCE(channel->parent.enabled, 1);
599 end:
600 mutex_unlock(&sessions_mutex);
601 return ret;
602 }
603
604 int lttng_channel_disable(struct lttng_kernel_channel_buffer *channel)
605 {
606 int ret = 0;
607
608 mutex_lock(&sessions_mutex);
609 if (channel->priv->channel_type == METADATA_CHANNEL) {
610 ret = -EPERM;
611 goto end;
612 }
613 if (!channel->parent.enabled) {
614 ret = -EEXIST;
615 goto end;
616 }
617 /* Set atomically the state to "disabled" */
618 WRITE_ONCE(channel->parent.enabled, 0);
619 /* Set transient enabler state to "enabled" */
620 channel->priv->parent.tstate = 0;
621 lttng_session_sync_event_enablers(channel->parent.session);
622 end:
623 mutex_unlock(&sessions_mutex);
624 return ret;
625 }
626
627 int lttng_event_enable(struct lttng_kernel_event_common *event)
628 {
629 int ret = 0;
630
631 mutex_lock(&sessions_mutex);
632 switch (event->type) {
633 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
634 {
635 struct lttng_kernel_event_recorder *event_recorder =
636 container_of(event, struct lttng_kernel_event_recorder, parent);
637
638 if (event_recorder->chan->priv->channel_type == METADATA_CHANNEL) {
639 ret = -EPERM;
640 goto end;
641 }
642 break;
643 }
644 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
645 switch (event->priv->instrumentation) {
646 case LTTNG_KERNEL_ABI_KRETPROBE:
647 ret = -EINVAL;
648 goto end;
649 default:
650 break;
651 }
652 break;
653 default:
654 break;
655 }
656
657 if (event->enabled) {
658 ret = -EEXIST;
659 goto end;
660 }
661 switch (event->priv->instrumentation) {
662 case LTTNG_KERNEL_ABI_TRACEPOINT: /* Fall-through */
663 case LTTNG_KERNEL_ABI_SYSCALL:
664 ret = -EINVAL;
665 break;
666
667 case LTTNG_KERNEL_ABI_KPROBE: /* Fall-through */
668 case LTTNG_KERNEL_ABI_UPROBE:
669 WRITE_ONCE(event->enabled, 1);
670 break;
671
672 case LTTNG_KERNEL_ABI_KRETPROBE:
673 ret = lttng_kretprobes_event_enable_state(event, 1);
674 break;
675
676 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
677 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
678 default:
679 WARN_ON_ONCE(1);
680 ret = -EINVAL;
681 }
682 end:
683 mutex_unlock(&sessions_mutex);
684 return ret;
685 }
686
687 int lttng_event_disable(struct lttng_kernel_event_common *event)
688 {
689 int ret = 0;
690
691 mutex_lock(&sessions_mutex);
692 switch (event->type) {
693 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
694 {
695 struct lttng_kernel_event_recorder *event_recorder =
696 container_of(event, struct lttng_kernel_event_recorder, parent);
697
698 if (event_recorder->chan->priv->channel_type == METADATA_CHANNEL) {
699 ret = -EPERM;
700 goto end;
701 }
702 break;
703 }
704 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
705 switch (event->priv->instrumentation) {
706 case LTTNG_KERNEL_ABI_KRETPROBE:
707 ret = -EINVAL;
708 goto end;
709 default:
710 break;
711 }
712 break;
713 default:
714 break;
715 }
716
717 if (!event->enabled) {
718 ret = -EEXIST;
719 goto end;
720 }
721 switch (event->priv->instrumentation) {
722 case LTTNG_KERNEL_ABI_TRACEPOINT: /* Fall-through */
723 case LTTNG_KERNEL_ABI_SYSCALL:
724 ret = -EINVAL;
725 break;
726
727 case LTTNG_KERNEL_ABI_KPROBE: /* Fall-through */
728 case LTTNG_KERNEL_ABI_UPROBE:
729 WRITE_ONCE(event->enabled, 0);
730 break;
731
732 case LTTNG_KERNEL_ABI_KRETPROBE:
733 ret = lttng_kretprobes_event_enable_state(event, 0);
734 break;
735
736 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
737 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
738 default:
739 WARN_ON_ONCE(1);
740 ret = -EINVAL;
741 }
742 end:
743 mutex_unlock(&sessions_mutex);
744 return ret;
745 }
746
747 struct lttng_kernel_channel_buffer *lttng_channel_create(struct lttng_kernel_session *session,
748 const char *transport_name,
749 void *buf_addr,
750 size_t subbuf_size, size_t num_subbuf,
751 unsigned int switch_timer_interval,
752 unsigned int read_timer_interval,
753 enum channel_type channel_type)
754 {
755 struct lttng_kernel_channel_buffer *chan;
756 struct lttng_kernel_channel_buffer_private *chan_priv;
757 struct lttng_transport *transport = NULL;
758
759 mutex_lock(&sessions_mutex);
760 if (session->priv->been_active && channel_type != METADATA_CHANNEL)
761 goto active; /* Refuse to add channel to active session */
762 transport = lttng_transport_find(transport_name);
763 if (!transport) {
764 printk(KERN_WARNING "LTTng: transport %s not found\n",
765 transport_name);
766 goto notransport;
767 }
768 if (!try_module_get(transport->owner)) {
769 printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
770 goto notransport;
771 }
772 chan = kzalloc(sizeof(struct lttng_kernel_channel_buffer), GFP_KERNEL);
773 if (!chan)
774 goto nomem;
775 chan_priv = kzalloc(sizeof(struct lttng_kernel_channel_buffer_private), GFP_KERNEL);
776 if (!chan_priv)
777 goto nomem_priv;
778 chan->priv = chan_priv;
779 chan_priv->pub = chan;
780 chan->parent.type = LTTNG_KERNEL_CHANNEL_TYPE_BUFFER;
781 chan->parent.session = session;
782 chan->priv->id = session->priv->free_chan_id++;
783 chan->ops = &transport->ops;
784 /*
785 * Note: the channel creation op already writes into the packet
786 * headers. Therefore the "chan" information used as input
787 * should be already accessible.
788 */
789 chan->priv->rb_chan = transport->ops.priv->channel_create(transport_name,
790 chan, buf_addr, subbuf_size, num_subbuf,
791 switch_timer_interval, read_timer_interval);
792 if (!chan->priv->rb_chan)
793 goto create_error;
794 chan->priv->parent.tstate = 1;
795 chan->parent.enabled = 1;
796 chan->priv->transport = transport;
797 chan->priv->channel_type = channel_type;
798 list_add(&chan->priv->node, &session->priv->chan);
799 mutex_unlock(&sessions_mutex);
800 return chan;
801
802 create_error:
803 kfree(chan_priv);
804 nomem_priv:
805 kfree(chan);
806 nomem:
807 if (transport)
808 module_put(transport->owner);
809 notransport:
810 active:
811 mutex_unlock(&sessions_mutex);
812 return NULL;
813 }
814
815 /*
816 * Only used internally at session destruction for per-cpu channels, and
817 * when metadata channel is released.
818 * Needs to be called with sessions mutex held.
819 */
820 static
821 void _lttng_channel_destroy(struct lttng_kernel_channel_buffer *chan)
822 {
823 chan->ops->priv->channel_destroy(chan->priv->rb_chan);
824 module_put(chan->priv->transport->owner);
825 list_del(&chan->priv->node);
826 lttng_kernel_destroy_context(chan->priv->ctx);
827 kfree(chan->priv);
828 kfree(chan);
829 }
830
831 void lttng_metadata_channel_destroy(struct lttng_kernel_channel_buffer *chan)
832 {
833 BUG_ON(chan->priv->channel_type != METADATA_CHANNEL);
834
835 /* Protect the metadata cache with the sessions_mutex. */
836 mutex_lock(&sessions_mutex);
837 _lttng_channel_destroy(chan);
838 mutex_unlock(&sessions_mutex);
839 }
840 EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy);
841
842 static
843 void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream)
844 {
845 stream->finalized = 1;
846 wake_up_interruptible(&stream->read_wait);
847 }
848
849
850 /*
851 * Supports event creation while tracing session is active.
852 * Needs to be called with sessions mutex held.
853 */
854 struct lttng_kernel_event_recorder *_lttng_kernel_event_recorder_create(struct lttng_kernel_channel_buffer *chan,
855 struct lttng_kernel_abi_event *event_param,
856 const struct lttng_kernel_event_desc *event_desc,
857 enum lttng_kernel_abi_instrumentation itype)
858 {
859 struct lttng_kernel_session *session = chan->parent.session;
860 struct lttng_kernel_event_recorder *event_recorder;
861 struct lttng_kernel_event_recorder_private *event_recorder_priv;
862 const char *event_name;
863 struct hlist_head *head;
864 int ret;
865
866 if (chan->priv->free_event_id == -1U) {
867 ret = -EMFILE;
868 goto full;
869 }
870
871 switch (itype) {
872 case LTTNG_KERNEL_ABI_TRACEPOINT:
873 event_name = event_desc->event_name;
874 break;
875
876 case LTTNG_KERNEL_ABI_KPROBE: /* Fall-through */
877 case LTTNG_KERNEL_ABI_UPROBE: /* Fall-through */
878 case LTTNG_KERNEL_ABI_KRETPROBE: /* Fall-through */
879 case LTTNG_KERNEL_ABI_SYSCALL:
880 event_name = event_param->name;
881 break;
882
883 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
884 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
885 default:
886 WARN_ON_ONCE(1);
887 ret = -EINVAL;
888 goto type_error;
889 }
890
891 head = utils_borrow_hash_table_bucket(session->priv->events_ht.table,
892 LTTNG_EVENT_HT_SIZE, event_name);
893 lttng_hlist_for_each_entry(event_recorder_priv, head, hlist) {
894 WARN_ON_ONCE(!event_recorder_priv->parent.desc);
895 if (!strncmp(event_recorder_priv->parent.desc->event_name, event_name,
896 LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1)
897 && chan == event_recorder_priv->pub->chan) {
898 ret = -EEXIST;
899 goto exist;
900 }
901 }
902
903 event_recorder = kmem_cache_zalloc(event_recorder_cache, GFP_KERNEL);
904 if (!event_recorder) {
905 ret = -ENOMEM;
906 goto cache_error;
907 }
908 event_recorder_priv = kmem_cache_zalloc(event_recorder_private_cache, GFP_KERNEL);
909 if (!event_recorder_priv) {
910 ret = -ENOMEM;
911 goto cache_private_error;
912 }
913 event_recorder_priv->pub = event_recorder;
914 event_recorder_priv->parent.pub = &event_recorder->parent;
915 event_recorder->priv = event_recorder_priv;
916 event_recorder->parent.priv = &event_recorder_priv->parent;
917 event_recorder->parent.type = LTTNG_KERNEL_EVENT_TYPE_RECORDER;
918
919 event_recorder->parent.run_filter = lttng_kernel_interpret_event_filter;
920 event_recorder->chan = chan;
921 event_recorder->priv->id = chan->priv->free_event_id++;
922 event_recorder->priv->parent.instrumentation = itype;
923 INIT_LIST_HEAD(&event_recorder->priv->parent.filter_bytecode_runtime_head);
924 INIT_LIST_HEAD(&event_recorder->priv->parent.enablers_ref_head);
925
926 switch (itype) {
927 case LTTNG_KERNEL_ABI_TRACEPOINT:
928 /* Event will be enabled by enabler sync. */
929 event_recorder->parent.enabled = 0;
930 event_recorder->priv->parent.registered = 0;
931 event_recorder->priv->parent.desc = lttng_event_desc_get(event_name);
932 if (!event_recorder->priv->parent.desc) {
933 ret = -ENOENT;
934 goto register_error;
935 }
936 /* Populate lttng_event structure before event registration. */
937 smp_wmb();
938 break;
939
940 case LTTNG_KERNEL_ABI_KPROBE:
941 /*
942 * Needs to be explicitly enabled after creation, since
943 * we may want to apply filters.
944 */
945 event_recorder->parent.enabled = 0;
946 event_recorder->priv->parent.registered = 1;
947 /*
948 * Populate lttng_event structure before event
949 * registration.
950 */
951 smp_wmb();
952 ret = lttng_kprobes_register_event(event_name,
953 event_param->u.kprobe.symbol_name,
954 event_param->u.kprobe.offset,
955 event_param->u.kprobe.addr,
956 event_recorder);
957 if (ret) {
958 ret = -EINVAL;
959 goto register_error;
960 }
961 ret = try_module_get(event_recorder->priv->parent.desc->owner);
962 WARN_ON_ONCE(!ret);
963 break;
964
965 case LTTNG_KERNEL_ABI_KRETPROBE:
966 {
967 struct lttng_kernel_event_recorder *event_recorder_return;
968 struct lttng_kernel_event_recorder_private *event_recorder_return_priv;
969
970 /* kretprobe defines 2 events */
971 /*
972 * Needs to be explicitly enabled after creation, since
973 * we may want to apply filters.
974 */
975 event_recorder->parent.enabled = 0;
976 event_recorder->priv->parent.registered = 1;
977
978 event_recorder_return = kmem_cache_zalloc(event_recorder_cache, GFP_KERNEL);
979 if (!event_recorder_return) {
980 ret = -ENOMEM;
981 goto register_error;
982 }
983 event_recorder_return_priv = kmem_cache_zalloc(event_recorder_private_cache, GFP_KERNEL);
984 if (!event_recorder_return_priv) {
985 kmem_cache_free(event_recorder_cache, event_recorder_return);
986 ret = -ENOMEM;
987 goto register_error;
988 }
989 event_recorder_return_priv->pub = event_recorder_return;
990 event_recorder_return_priv->parent.pub = &event_recorder_return->parent;
991 event_recorder_return->priv = event_recorder_return_priv;
992 event_recorder_return->parent.priv = &event_recorder_return_priv->parent;
993 event_recorder_return->parent.type = LTTNG_KERNEL_EVENT_TYPE_RECORDER;
994
995 event_recorder_return->parent.run_filter = lttng_kernel_interpret_event_filter;
996 event_recorder_return->chan = chan;
997 event_recorder_return->priv->id = chan->priv->free_event_id++;
998 event_recorder_return->priv->parent.instrumentation = itype;
999 event_recorder_return->parent.enabled = 0;
1000 event_recorder_return->priv->parent.registered = 1;
1001 INIT_LIST_HEAD(&event_recorder_return->priv->parent.filter_bytecode_runtime_head);
1002 INIT_LIST_HEAD(&event_recorder_return->priv->parent.enablers_ref_head);
1003 /*
1004 * Populate lttng_event structure before kretprobe registration.
1005 */
1006 smp_wmb();
1007 ret = lttng_kretprobes_register(event_name,
1008 event_param->u.kretprobe.symbol_name,
1009 event_param->u.kretprobe.offset,
1010 event_param->u.kretprobe.addr,
1011 event_recorder, event_recorder_return);
1012 if (ret) {
1013 kmem_cache_free(event_recorder_private_cache, event_recorder_return_priv);
1014 kmem_cache_free(event_recorder_cache, event_recorder_return);
1015 ret = -EINVAL;
1016 goto register_error;
1017 }
1018 /* Take 2 refs on the module: one per event. */
1019 ret = try_module_get(event_recorder->priv->parent.desc->owner);
1020 WARN_ON_ONCE(!ret);
1021 ret = try_module_get(event_recorder_return->priv->parent.desc->owner);
1022 WARN_ON_ONCE(!ret);
1023 ret = _lttng_event_metadata_statedump(chan->parent.session, chan,
1024 event_recorder_return);
1025 WARN_ON_ONCE(ret > 0);
1026 if (ret) {
1027 kmem_cache_free(event_recorder_private_cache, event_recorder_return_priv);
1028 kmem_cache_free(event_recorder_cache, event_recorder_return);
1029 module_put(event_recorder_return->priv->parent.desc->owner);
1030 module_put(event_recorder->priv->parent.desc->owner);
1031 goto statedump_error;
1032 }
1033 list_add(&event_recorder_return->priv->node, &chan->parent.session->priv->events);
1034 break;
1035 }
1036
1037 case LTTNG_KERNEL_ABI_SYSCALL:
1038 /*
1039 * Needs to be explicitly enabled after creation, since
1040 * we may want to apply filters.
1041 */
1042 event_recorder->parent.enabled = 0;
1043 event_recorder->priv->parent.registered = 0;
1044 event_recorder->priv->parent.desc = event_desc;
1045 switch (event_param->u.syscall.entryexit) {
1046 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
1047 ret = -EINVAL;
1048 goto register_error;
1049 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
1050 event_recorder->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_ENTRY;
1051 break;
1052 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
1053 event_recorder->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_EXIT;
1054 break;
1055 }
1056 switch (event_param->u.syscall.abi) {
1057 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
1058 ret = -EINVAL;
1059 goto register_error;
1060 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
1061 event_recorder->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE;
1062 break;
1063 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
1064 event_recorder->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT;
1065 break;
1066 }
1067 if (!event_recorder->priv->parent.desc) {
1068 ret = -EINVAL;
1069 goto register_error;
1070 }
1071 break;
1072
1073 case LTTNG_KERNEL_ABI_UPROBE:
1074 /*
1075 * Needs to be explicitly enabled after creation, since
1076 * we may want to apply filters.
1077 */
1078 event_recorder->parent.enabled = 0;
1079 event_recorder->priv->parent.registered = 1;
1080
1081 /*
1082 * Populate lttng_event structure before event
1083 * registration.
1084 */
1085 smp_wmb();
1086
1087 ret = lttng_uprobes_register_event(event_param->name,
1088 event_param->u.uprobe.fd,
1089 event_recorder);
1090 if (ret)
1091 goto register_error;
1092 ret = try_module_get(event_recorder->priv->parent.desc->owner);
1093 WARN_ON_ONCE(!ret);
1094 break;
1095
1096 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
1097 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
1098 default:
1099 WARN_ON_ONCE(1);
1100 ret = -EINVAL;
1101 goto register_error;
1102 }
1103 ret = _lttng_event_metadata_statedump(chan->parent.session, chan, event_recorder);
1104 WARN_ON_ONCE(ret > 0);
1105 if (ret) {
1106 goto statedump_error;
1107 }
1108 hlist_add_head(&event_recorder->priv->hlist, head);
1109 list_add(&event_recorder->priv->node, &chan->parent.session->priv->events);
1110 return event_recorder;
1111
1112 statedump_error:
1113 /* If a statedump error occurs, events will not be readable. */
1114 register_error:
1115 kmem_cache_free(event_recorder_private_cache, event_recorder_priv);
1116 cache_private_error:
1117 kmem_cache_free(event_recorder_cache, event_recorder);
1118 cache_error:
1119 exist:
1120 type_error:
1121 full:
1122 return ERR_PTR(ret);
1123 }
1124
1125 struct lttng_kernel_event_notifier *_lttng_event_notifier_create(
1126 const struct lttng_kernel_event_desc *event_desc,
1127 uint64_t token, uint64_t error_counter_index,
1128 struct lttng_event_notifier_group *event_notifier_group,
1129 struct lttng_kernel_abi_event_notifier *event_notifier_param,
1130 enum lttng_kernel_abi_instrumentation itype)
1131 {
1132 struct lttng_kernel_event_notifier *event_notifier;
1133 struct lttng_kernel_event_notifier_private *event_notifier_priv;
1134 struct lttng_counter *error_counter;
1135 const char *event_name;
1136 struct hlist_head *head;
1137 int ret;
1138
1139 switch (itype) {
1140 case LTTNG_KERNEL_ABI_TRACEPOINT:
1141 event_name = event_desc->event_name;
1142 break;
1143
1144 case LTTNG_KERNEL_ABI_KPROBE: /* Fall-through */
1145 case LTTNG_KERNEL_ABI_UPROBE: /* Fall-through */
1146 case LTTNG_KERNEL_ABI_SYSCALL:
1147 event_name = event_notifier_param->event.name;
1148 break;
1149
1150 case LTTNG_KERNEL_ABI_KRETPROBE: /* Fall-through */
1151 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
1152 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
1153 default:
1154 WARN_ON_ONCE(1);
1155 ret = -EINVAL;
1156 goto type_error;
1157 }
1158
1159 head = utils_borrow_hash_table_bucket(event_notifier_group->event_notifiers_ht.table,
1160 LTTNG_EVENT_NOTIFIER_HT_SIZE, event_name);
1161 lttng_hlist_for_each_entry(event_notifier_priv, head, hlist) {
1162 WARN_ON_ONCE(!event_notifier_priv->parent.desc);
1163 if (!strncmp(event_notifier_priv->parent.desc->event_name, event_name,
1164 LTTNG_KERNEL_ABI_SYM_NAME_LEN - 1)
1165 && event_notifier_group == event_notifier_priv->group
1166 && token == event_notifier_priv->parent.user_token) {
1167 ret = -EEXIST;
1168 goto exist;
1169 }
1170 }
1171
1172 event_notifier = kmem_cache_zalloc(event_notifier_cache, GFP_KERNEL);
1173 if (!event_notifier) {
1174 ret = -ENOMEM;
1175 goto cache_error;
1176 }
1177 event_notifier_priv = kmem_cache_zalloc(event_notifier_private_cache, GFP_KERNEL);
1178 if (!event_notifier_priv) {
1179 ret = -ENOMEM;
1180 goto cache_private_error;
1181 }
1182 event_notifier_priv->pub = event_notifier;
1183 event_notifier_priv->parent.pub = &event_notifier->parent;
1184 event_notifier->priv = event_notifier_priv;
1185 event_notifier->parent.priv = &event_notifier_priv->parent;
1186 event_notifier->parent.type = LTTNG_KERNEL_EVENT_TYPE_NOTIFIER;
1187
1188 event_notifier->priv->group = event_notifier_group;
1189 event_notifier->priv->parent.user_token = token;
1190 event_notifier->priv->error_counter_index = error_counter_index;
1191 event_notifier->priv->num_captures = 0;
1192 event_notifier->priv->parent.instrumentation = itype;
1193 event_notifier->notification_send = lttng_event_notifier_notification_send;
1194 INIT_LIST_HEAD(&event_notifier->priv->parent.filter_bytecode_runtime_head);
1195 INIT_LIST_HEAD(&event_notifier->priv->parent.enablers_ref_head);
1196 INIT_LIST_HEAD(&event_notifier->priv->capture_bytecode_runtime_head);
1197 event_notifier->parent.run_filter = lttng_kernel_interpret_event_filter;
1198
1199 switch (itype) {
1200 case LTTNG_KERNEL_ABI_TRACEPOINT:
1201 /* Event will be enabled by enabler sync. */
1202 event_notifier->parent.enabled = 0;
1203 event_notifier->priv->parent.registered = 0;
1204 event_notifier->priv->parent.desc = lttng_event_desc_get(event_name);
1205 if (!event_notifier->priv->parent.desc) {
1206 ret = -ENOENT;
1207 goto register_error;
1208 }
1209 /* Populate lttng_event_notifier structure before event registration. */
1210 smp_wmb();
1211 break;
1212
1213 case LTTNG_KERNEL_ABI_KPROBE:
1214 /*
1215 * Needs to be explicitly enabled after creation, since
1216 * we may want to apply filters.
1217 */
1218 event_notifier->parent.enabled = 0;
1219 event_notifier->priv->parent.registered = 1;
1220 /*
1221 * Populate lttng_event_notifier structure before event
1222 * registration.
1223 */
1224 smp_wmb();
1225 ret = lttng_kprobes_register_event_notifier(
1226 event_notifier_param->event.u.kprobe.symbol_name,
1227 event_notifier_param->event.u.kprobe.offset,
1228 event_notifier_param->event.u.kprobe.addr,
1229 event_notifier);
1230 if (ret) {
1231 ret = -EINVAL;
1232 goto register_error;
1233 }
1234 ret = try_module_get(event_notifier->priv->parent.desc->owner);
1235 WARN_ON_ONCE(!ret);
1236 break;
1237
1238 case LTTNG_KERNEL_ABI_SYSCALL:
1239 /*
1240 * Needs to be explicitly enabled after creation, since
1241 * we may want to apply filters.
1242 */
1243 event_notifier->parent.enabled = 0;
1244 event_notifier->priv->parent.registered = 0;
1245 event_notifier->priv->parent.desc = event_desc;
1246 switch (event_notifier_param->event.u.syscall.entryexit) {
1247 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
1248 ret = -EINVAL;
1249 goto register_error;
1250 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
1251 event_notifier->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_ENTRY;
1252 break;
1253 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
1254 event_notifier->priv->parent.u.syscall.entryexit = LTTNG_SYSCALL_EXIT;
1255 break;
1256 }
1257 switch (event_notifier_param->event.u.syscall.abi) {
1258 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
1259 ret = -EINVAL;
1260 goto register_error;
1261 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
1262 event_notifier->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE;
1263 break;
1264 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
1265 event_notifier->priv->parent.u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT;
1266 break;
1267 }
1268
1269 if (!event_notifier->priv->parent.desc) {
1270 ret = -EINVAL;
1271 goto register_error;
1272 }
1273 break;
1274
1275 case LTTNG_KERNEL_ABI_UPROBE:
1276 /*
1277 * Needs to be explicitly enabled after creation, since
1278 * we may want to apply filters.
1279 */
1280 event_notifier->parent.enabled = 0;
1281 event_notifier->priv->parent.registered = 1;
1282
1283 /*
1284 * Populate lttng_event_notifier structure before
1285 * event_notifier registration.
1286 */
1287 smp_wmb();
1288
1289 ret = lttng_uprobes_register_event_notifier(
1290 event_notifier_param->event.name,
1291 event_notifier_param->event.u.uprobe.fd,
1292 event_notifier);
1293 if (ret)
1294 goto register_error;
1295 ret = try_module_get(event_notifier->priv->parent.desc->owner);
1296 WARN_ON_ONCE(!ret);
1297 break;
1298
1299 case LTTNG_KERNEL_ABI_KRETPROBE: /* Fall-through */
1300 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
1301 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
1302 default:
1303 WARN_ON_ONCE(1);
1304 ret = -EINVAL;
1305 goto register_error;
1306 }
1307
1308 list_add(&event_notifier->priv->node, &event_notifier_group->event_notifiers_head);
1309 hlist_add_head(&event_notifier->priv->hlist, head);
1310
1311 /*
1312 * Clear the error counter bucket. The sessiond keeps track of which
1313 * bucket is currently in use. We trust it. The session lock
1314 * synchronizes against concurrent creation of the error
1315 * counter.
1316 */
1317 error_counter = event_notifier_group->error_counter;
1318 if (error_counter) {
1319 size_t dimension_index[1];
1320
1321 /*
1322 * Check that the index is within the boundary of the counter.
1323 */
1324 if (event_notifier->priv->error_counter_index >= event_notifier_group->error_counter_len) {
1325 printk(KERN_INFO "LTTng: event_notifier: Error counter index out-of-bound: counter-len=%zu, index=%llu\n",
1326 event_notifier_group->error_counter_len, event_notifier->priv->error_counter_index);
1327 ret = -EINVAL;
1328 goto register_error;
1329 }
1330
1331 dimension_index[0] = event_notifier->priv->error_counter_index;
1332 ret = error_counter->ops->counter_clear(error_counter->counter, dimension_index);
1333 if (ret) {
1334 printk(KERN_INFO "LTTng: event_notifier: Unable to clear error counter bucket %llu\n",
1335 event_notifier->priv->error_counter_index);
1336 goto register_error;
1337 }
1338 }
1339
1340 return event_notifier;
1341
1342 register_error:
1343 kmem_cache_free(event_notifier_private_cache, event_notifier_priv);
1344 cache_private_error:
1345 kmem_cache_free(event_notifier_cache, event_notifier);
1346 cache_error:
1347 exist:
1348 type_error:
1349 return ERR_PTR(ret);
1350 }
1351
1352 int lttng_kernel_counter_read(struct lttng_counter *counter,
1353 const size_t *dim_indexes, int32_t cpu,
1354 int64_t *val, bool *overflow, bool *underflow)
1355 {
1356 return counter->ops->counter_read(counter->counter, dim_indexes,
1357 cpu, val, overflow, underflow);
1358 }
1359
1360 int lttng_kernel_counter_aggregate(struct lttng_counter *counter,
1361 const size_t *dim_indexes, int64_t *val,
1362 bool *overflow, bool *underflow)
1363 {
1364 return counter->ops->counter_aggregate(counter->counter, dim_indexes,
1365 val, overflow, underflow);
1366 }
1367
1368 int lttng_kernel_counter_clear(struct lttng_counter *counter,
1369 const size_t *dim_indexes)
1370 {
1371 return counter->ops->counter_clear(counter->counter, dim_indexes);
1372 }
1373
1374 struct lttng_kernel_event_recorder *lttng_kernel_event_recorder_create(struct lttng_kernel_channel_buffer *chan,
1375 struct lttng_kernel_abi_event *event_param,
1376 const struct lttng_kernel_event_desc *event_desc,
1377 enum lttng_kernel_abi_instrumentation itype)
1378 {
1379 struct lttng_kernel_event_recorder *event;
1380
1381 mutex_lock(&sessions_mutex);
1382 event = _lttng_kernel_event_recorder_create(chan, event_param, event_desc, itype);
1383 mutex_unlock(&sessions_mutex);
1384 return event;
1385 }
1386
1387 struct lttng_kernel_event_notifier *lttng_event_notifier_create(
1388 const struct lttng_kernel_event_desc *event_desc,
1389 uint64_t id, uint64_t error_counter_index,
1390 struct lttng_event_notifier_group *event_notifier_group,
1391 struct lttng_kernel_abi_event_notifier *event_notifier_param,
1392 enum lttng_kernel_abi_instrumentation itype)
1393 {
1394 struct lttng_kernel_event_notifier *event_notifier;
1395
1396 mutex_lock(&sessions_mutex);
1397 event_notifier = _lttng_event_notifier_create(event_desc, id,
1398 error_counter_index, event_notifier_group,
1399 event_notifier_param, itype);
1400 mutex_unlock(&sessions_mutex);
1401 return event_notifier;
1402 }
1403
1404 /* Only used for tracepoints for now. */
1405 static
1406 void register_event(struct lttng_kernel_event_recorder *event_recorder)
1407 {
1408 const struct lttng_kernel_event_desc *desc;
1409 int ret = -EINVAL;
1410
1411 if (event_recorder->priv->parent.registered)
1412 return;
1413
1414 desc = event_recorder->priv->parent.desc;
1415 switch (event_recorder->priv->parent.instrumentation) {
1416 case LTTNG_KERNEL_ABI_TRACEPOINT:
1417 ret = lttng_wrapper_tracepoint_probe_register(desc->event_kname,
1418 desc->tp_class->probe_callback,
1419 event_recorder);
1420 break;
1421
1422 case LTTNG_KERNEL_ABI_SYSCALL:
1423 ret = lttng_syscall_filter_enable_event(event_recorder->chan, event_recorder);
1424 break;
1425
1426 case LTTNG_KERNEL_ABI_KPROBE: /* Fall-through */
1427 case LTTNG_KERNEL_ABI_UPROBE: /* Fall-through */
1428 case LTTNG_KERNEL_ABI_KRETPROBE:
1429 ret = 0;
1430 break;
1431
1432 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
1433 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
1434 default:
1435 WARN_ON_ONCE(1);
1436 }
1437 if (!ret)
1438 event_recorder->priv->parent.registered = 1;
1439 }
1440
1441 /*
1442 * Only used internally at session destruction.
1443 */
1444 int _lttng_event_unregister(struct lttng_kernel_event_recorder *event_recorder)
1445 {
1446 struct lttng_kernel_event_common_private *event_priv = &event_recorder->priv->parent;
1447 const struct lttng_kernel_event_desc *desc;
1448 int ret = -EINVAL;
1449
1450 if (!event_priv->registered)
1451 return 0;
1452
1453 desc = event_priv->desc;
1454 switch (event_priv->instrumentation) {
1455 case LTTNG_KERNEL_ABI_TRACEPOINT:
1456 ret = lttng_wrapper_tracepoint_probe_unregister(event_priv->desc->event_kname,
1457 event_priv->desc->tp_class->probe_callback,
1458 event_recorder);
1459 break;
1460
1461 case LTTNG_KERNEL_ABI_KPROBE:
1462 lttng_kprobes_unregister_event(event_recorder);
1463 ret = 0;
1464 break;
1465
1466 case LTTNG_KERNEL_ABI_KRETPROBE:
1467 lttng_kretprobes_unregister(event_recorder);
1468 ret = 0;
1469 break;
1470
1471 case LTTNG_KERNEL_ABI_SYSCALL:
1472 ret = lttng_syscall_filter_disable_event(event_recorder->chan, event_recorder);
1473 break;
1474
1475 case LTTNG_KERNEL_ABI_NOOP:
1476 ret = 0;
1477 break;
1478
1479 case LTTNG_KERNEL_ABI_UPROBE:
1480 lttng_uprobes_unregister_event(event_recorder);
1481 ret = 0;
1482 break;
1483
1484 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
1485 default:
1486 WARN_ON_ONCE(1);
1487 }
1488 if (!ret)
1489 event_priv->registered = 0;
1490 return ret;
1491 }
1492
1493 /* Only used for tracepoints for now. */
1494 static
1495 void register_event_notifier(struct lttng_kernel_event_notifier *event_notifier)
1496 {
1497 const struct lttng_kernel_event_desc *desc;
1498 int ret = -EINVAL;
1499
1500 if (event_notifier->priv->parent.registered)
1501 return;
1502
1503 desc = event_notifier->priv->parent.desc;
1504 switch (event_notifier->priv->parent.instrumentation) {
1505 case LTTNG_KERNEL_ABI_TRACEPOINT:
1506 ret = lttng_wrapper_tracepoint_probe_register(desc->event_kname,
1507 desc->tp_class->probe_callback,
1508 event_notifier);
1509 break;
1510
1511 case LTTNG_KERNEL_ABI_SYSCALL:
1512 ret = lttng_syscall_filter_enable_event_notifier(event_notifier);
1513 break;
1514
1515 case LTTNG_KERNEL_ABI_KPROBE: /* Fall-through */
1516 case LTTNG_KERNEL_ABI_UPROBE:
1517 ret = 0;
1518 break;
1519
1520 case LTTNG_KERNEL_ABI_KRETPROBE: /* Fall-through */
1521 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
1522 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
1523 default:
1524 WARN_ON_ONCE(1);
1525 }
1526 if (!ret)
1527 event_notifier->priv->parent.registered = 1;
1528 }
1529
1530 static
1531 int _lttng_event_notifier_unregister(
1532 struct lttng_kernel_event_notifier *event_notifier)
1533 {
1534 const struct lttng_kernel_event_desc *desc;
1535 int ret = -EINVAL;
1536
1537 if (!event_notifier->priv->parent.registered)
1538 return 0;
1539
1540 desc = event_notifier->priv->parent.desc;
1541 switch (event_notifier->priv->parent.instrumentation) {
1542 case LTTNG_KERNEL_ABI_TRACEPOINT:
1543 ret = lttng_wrapper_tracepoint_probe_unregister(event_notifier->priv->parent.desc->event_kname,
1544 event_notifier->priv->parent.desc->tp_class->probe_callback,
1545 event_notifier);
1546 break;
1547
1548 case LTTNG_KERNEL_ABI_KPROBE:
1549 lttng_kprobes_unregister_event_notifier(event_notifier);
1550 ret = 0;
1551 break;
1552
1553 case LTTNG_KERNEL_ABI_UPROBE:
1554 lttng_uprobes_unregister_event_notifier(event_notifier);
1555 ret = 0;
1556 break;
1557
1558 case LTTNG_KERNEL_ABI_SYSCALL:
1559 ret = lttng_syscall_filter_disable_event_notifier(event_notifier);
1560 break;
1561
1562 case LTTNG_KERNEL_ABI_KRETPROBE: /* Fall-through */
1563 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
1564 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
1565 default:
1566 WARN_ON_ONCE(1);
1567 }
1568 if (!ret)
1569 event_notifier->priv->parent.registered = 0;
1570 return ret;
1571 }
1572
1573 /*
1574 * Only used internally at session destruction.
1575 */
1576 static
1577 void _lttng_event_destroy(struct lttng_kernel_event_common *event)
1578 {
1579 struct lttng_kernel_event_common_private *event_priv = event->priv;
1580 struct lttng_enabler_ref *enabler_ref, *tmp_enabler_ref;
1581
1582 lttng_free_event_filter_runtime(event);
1583 /* Free event enabler refs */
1584 list_for_each_entry_safe(enabler_ref, tmp_enabler_ref,
1585 &event_priv->enablers_ref_head, node)
1586 kfree(enabler_ref);
1587
1588 switch (event->type) {
1589 case LTTNG_KERNEL_EVENT_TYPE_RECORDER:
1590 {
1591 struct lttng_kernel_event_recorder *event_recorder =
1592 container_of(event, struct lttng_kernel_event_recorder, parent);
1593
1594 switch (event_priv->instrumentation) {
1595 case LTTNG_KERNEL_ABI_TRACEPOINT:
1596 lttng_event_desc_put(event_priv->desc);
1597 break;
1598
1599 case LTTNG_KERNEL_ABI_KPROBE:
1600 module_put(event_priv->desc->owner);
1601 lttng_kprobes_destroy_event_private(event_recorder);
1602 break;
1603
1604 case LTTNG_KERNEL_ABI_KRETPROBE:
1605 module_put(event_priv->desc->owner);
1606 lttng_kretprobes_destroy_private(event_recorder);
1607 break;
1608
1609 case LTTNG_KERNEL_ABI_SYSCALL:
1610 break;
1611
1612 case LTTNG_KERNEL_ABI_UPROBE:
1613 module_put(event_priv->desc->owner);
1614 lttng_uprobes_destroy_event_private(event_recorder);
1615 break;
1616
1617 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
1618 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
1619 default:
1620 WARN_ON_ONCE(1);
1621 }
1622 list_del(&event_recorder->priv->node);
1623 kmem_cache_free(event_recorder_private_cache, event_recorder->priv);
1624 kmem_cache_free(event_recorder_cache, event_recorder);
1625 break;
1626 }
1627 case LTTNG_KERNEL_EVENT_TYPE_NOTIFIER:
1628 {
1629 struct lttng_kernel_event_notifier *event_notifier =
1630 container_of(event, struct lttng_kernel_event_notifier, parent);
1631
1632 switch (event_notifier->priv->parent.instrumentation) {
1633 case LTTNG_KERNEL_ABI_TRACEPOINT:
1634 lttng_event_desc_put(event_notifier->priv->parent.desc);
1635 break;
1636
1637 case LTTNG_KERNEL_ABI_KPROBE:
1638 module_put(event_notifier->priv->parent.desc->owner);
1639 lttng_kprobes_destroy_event_notifier_private(event_notifier);
1640 break;
1641
1642 case LTTNG_KERNEL_ABI_SYSCALL:
1643 break;
1644
1645 case LTTNG_KERNEL_ABI_UPROBE:
1646 module_put(event_notifier->priv->parent.desc->owner);
1647 lttng_uprobes_destroy_event_notifier_private(event_notifier);
1648 break;
1649
1650 case LTTNG_KERNEL_ABI_KRETPROBE: /* Fall-through */
1651 case LTTNG_KERNEL_ABI_FUNCTION: /* Fall-through */
1652 case LTTNG_KERNEL_ABI_NOOP: /* Fall-through */
1653 default:
1654 WARN_ON_ONCE(1);
1655 }
1656 list_del(&event_notifier->priv->node);
1657 kmem_cache_free(event_notifier_private_cache, event_notifier->priv);
1658 kmem_cache_free(event_notifier_cache, event_notifier);
1659 break;
1660 }
1661 default:
1662 WARN_ON_ONCE(1);
1663 }
1664 }
1665
1666 struct lttng_kernel_id_tracker *get_tracker(struct lttng_kernel_session *session,
1667 enum tracker_type tracker_type)
1668 {
1669 switch (tracker_type) {
1670 case TRACKER_PID:
1671 return &session->pid_tracker;
1672 case TRACKER_VPID:
1673 return &session->vpid_tracker;
1674 case TRACKER_UID:
1675 return &session->uid_tracker;
1676 case TRACKER_VUID:
1677 return &session->vuid_tracker;
1678 case TRACKER_GID:
1679 return &session->gid_tracker;
1680 case TRACKER_VGID:
1681 return &session->vgid_tracker;
1682 default:
1683 WARN_ON_ONCE(1);
1684 return NULL;
1685 }
1686 }
1687
1688 int lttng_session_track_id(struct lttng_kernel_session *session,
1689 enum tracker_type tracker_type, int id)
1690 {
1691 struct lttng_kernel_id_tracker *tracker;
1692 int ret;
1693
1694 tracker = get_tracker(session, tracker_type);
1695 if (!tracker)
1696 return -EINVAL;
1697 if (id < -1)
1698 return -EINVAL;
1699 mutex_lock(&sessions_mutex);
1700 if (id == -1) {
1701 /* track all ids: destroy tracker. */
1702 lttng_id_tracker_destroy(tracker, true);
1703 ret = 0;
1704 } else {
1705 ret = lttng_id_tracker_add(tracker, id);
1706 }
1707 mutex_unlock(&sessions_mutex);
1708 return ret;
1709 }
1710
1711 int lttng_session_untrack_id(struct lttng_kernel_session *session,
1712 enum tracker_type tracker_type, int id)
1713 {
1714 struct lttng_kernel_id_tracker *tracker;
1715 int ret;
1716
1717 tracker = get_tracker(session, tracker_type);
1718 if (!tracker)
1719 return -EINVAL;
1720 if (id < -1)
1721 return -EINVAL;
1722 mutex_lock(&sessions_mutex);
1723 if (id == -1) {
1724 /* untrack all ids: replace by empty tracker. */
1725 ret = lttng_id_tracker_empty_set(tracker);
1726 } else {
1727 ret = lttng_id_tracker_del(tracker, id);
1728 }
1729 mutex_unlock(&sessions_mutex);
1730 return ret;
1731 }
1732
1733 static
1734 void *id_list_start(struct seq_file *m, loff_t *pos)
1735 {
1736 struct lttng_kernel_id_tracker *id_tracker = m->private;
1737 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1738 struct lttng_id_hash_node *e;
1739 int iter = 0, i;
1740
1741 mutex_lock(&sessions_mutex);
1742 if (id_tracker_p) {
1743 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1744 struct hlist_head *head = &id_tracker_p->id_hash[i];
1745
1746 lttng_hlist_for_each_entry(e, head, hlist) {
1747 if (iter++ >= *pos)
1748 return e;
1749 }
1750 }
1751 } else {
1752 /* ID tracker disabled. */
1753 if (iter >= *pos && iter == 0) {
1754 return id_tracker_p; /* empty tracker */
1755 }
1756 iter++;
1757 }
1758 /* End of list */
1759 return NULL;
1760 }
1761
1762 /* Called with sessions_mutex held. */
1763 static
1764 void *id_list_next(struct seq_file *m, void *p, loff_t *ppos)
1765 {
1766 struct lttng_kernel_id_tracker *id_tracker = m->private;
1767 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1768 struct lttng_id_hash_node *e;
1769 int iter = 0, i;
1770
1771 (*ppos)++;
1772 if (id_tracker_p) {
1773 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1774 struct hlist_head *head = &id_tracker_p->id_hash[i];
1775
1776 lttng_hlist_for_each_entry(e, head, hlist) {
1777 if (iter++ >= *ppos)
1778 return e;
1779 }
1780 }
1781 } else {
1782 /* ID tracker disabled. */
1783 if (iter >= *ppos && iter == 0)
1784 return p; /* empty tracker */
1785 iter++;
1786 }
1787
1788 /* End of list */
1789 return NULL;
1790 }
1791
1792 static
1793 void id_list_stop(struct seq_file *m, void *p)
1794 {
1795 mutex_unlock(&sessions_mutex);
1796 }
1797
1798 static
1799 int id_list_show(struct seq_file *m, void *p)
1800 {
1801 struct lttng_kernel_id_tracker *id_tracker = m->private;
1802 struct lttng_kernel_id_tracker_rcu *id_tracker_p = id_tracker->p;
1803 int id;
1804
1805 if (p == id_tracker_p) {
1806 /* Tracker disabled. */
1807 id = -1;
1808 } else {
1809 const struct lttng_id_hash_node *e = p;
1810
1811 id = lttng_id_tracker_get_node_id(e);
1812 }
1813 switch (id_tracker->priv->tracker_type) {
1814 case TRACKER_PID:
1815 seq_printf(m, "process { pid = %d; };\n", id);
1816 break;
1817 case TRACKER_VPID:
1818 seq_printf(m, "process { vpid = %d; };\n", id);
1819 break;
1820 case TRACKER_UID:
1821 seq_printf(m, "user { uid = %d; };\n", id);
1822 break;
1823 case TRACKER_VUID:
1824 seq_printf(m, "user { vuid = %d; };\n", id);
1825 break;
1826 case TRACKER_GID:
1827 seq_printf(m, "group { gid = %d; };\n", id);
1828 break;
1829 case TRACKER_VGID:
1830 seq_printf(m, "group { vgid = %d; };\n", id);
1831 break;
1832 default:
1833 seq_printf(m, "UNKNOWN { field = %d };\n", id);
1834 }
1835 return 0;
1836 }
1837
1838 static
1839 const struct seq_operations lttng_tracker_ids_list_seq_ops = {
1840 .start = id_list_start,
1841 .next = id_list_next,
1842 .stop = id_list_stop,
1843 .show = id_list_show,
1844 };
1845
1846 static
1847 int lttng_tracker_ids_list_open(struct inode *inode, struct file *file)
1848 {
1849 return seq_open(file, &lttng_tracker_ids_list_seq_ops);
1850 }
1851
1852 static
1853 int lttng_tracker_ids_list_release(struct inode *inode, struct file *file)
1854 {
1855 struct seq_file *m = file->private_data;
1856 struct lttng_kernel_id_tracker *id_tracker = m->private;
1857 int ret;
1858
1859 WARN_ON_ONCE(!id_tracker);
1860 ret = seq_release(inode, file);
1861 if (!ret)
1862 fput(id_tracker->priv->session->priv->file);
1863 return ret;
1864 }
1865
1866 const struct file_operations lttng_tracker_ids_list_fops = {
1867 .owner = THIS_MODULE,
1868 .open = lttng_tracker_ids_list_open,
1869 .read = seq_read,
1870 .llseek = seq_lseek,
1871 .release = lttng_tracker_ids_list_release,
1872 };
1873
1874 int lttng_session_list_tracker_ids(struct lttng_kernel_session *session,
1875 enum tracker_type tracker_type)
1876 {
1877 struct file *tracker_ids_list_file;
1878 struct seq_file *m;
1879 int file_fd, ret;
1880
1881 file_fd = lttng_get_unused_fd();
1882 if (file_fd < 0) {
1883 ret = file_fd;
1884 goto fd_error;
1885 }
1886
1887 tracker_ids_list_file = anon_inode_getfile("[lttng_tracker_ids_list]",
1888 &lttng_tracker_ids_list_fops,
1889 NULL, O_RDWR);
1890 if (IS_ERR(tracker_ids_list_file)) {
1891 ret = PTR_ERR(tracker_ids_list_file);
1892 goto file_error;
1893 }
1894 if (!atomic_long_add_unless(&session->priv->file->f_count, 1, LONG_MAX)) {
1895 ret = -EOVERFLOW;
1896 goto refcount_error;
1897 }
1898 ret = lttng_tracker_ids_list_fops.open(NULL, tracker_ids_list_file);
1899 if (ret < 0)
1900 goto open_error;
1901 m = tracker_ids_list_file->private_data;
1902
1903 m->private = get_tracker(session, tracker_type);
1904 BUG_ON(!m->private);
1905 fd_install(file_fd, tracker_ids_list_file);
1906
1907 return file_fd;
1908
1909 open_error:
1910 atomic_long_dec(&session->priv->file->f_count);
1911 refcount_error:
1912 fput(tracker_ids_list_file);
1913 file_error:
1914 put_unused_fd(file_fd);
1915 fd_error:
1916 return ret;
1917 }
1918
1919 /*
1920 * Enabler management.
1921 */
1922 static
1923 int lttng_match_enabler_star_glob(const char *desc_name,
1924 const char *pattern)
1925 {
1926 if (!strutils_star_glob_match(pattern, LTTNG_SIZE_MAX,
1927 desc_name, LTTNG_SIZE_MAX))
1928 return 0;
1929 return 1;
1930 }
1931
1932 static
1933 int lttng_match_enabler_name(const char *desc_name,
1934 const char *name)
1935 {
1936 if (strcmp(desc_name, name))
1937 return 0;
1938 return 1;
1939 }
1940
1941 int lttng_desc_match_enabler(const struct lttng_kernel_event_desc *desc,
1942 struct lttng_enabler *enabler)
1943 {
1944 const char *desc_name, *enabler_name;
1945 bool compat = false, entry = false;
1946
1947 enabler_name = enabler->event_param.name;
1948 switch (enabler->event_param.instrumentation) {
1949 case LTTNG_KERNEL_ABI_TRACEPOINT:
1950 desc_name = desc->event_name;
1951 switch (enabler->format_type) {
1952 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
1953 return lttng_match_enabler_star_glob(desc_name, enabler_name);
1954 case LTTNG_ENABLER_FORMAT_NAME:
1955 return lttng_match_enabler_name(desc_name, enabler_name);
1956 default:
1957 return -EINVAL;
1958 }
1959 break;
1960
1961 case LTTNG_KERNEL_ABI_SYSCALL:
1962 desc_name = desc->event_name;
1963 if (!strncmp(desc_name, "compat_", strlen("compat_"))) {
1964 desc_name += strlen("compat_");
1965 compat = true;
1966 }
1967 if (!strncmp(desc_name, "syscall_exit_",
1968 strlen("syscall_exit_"))) {
1969 desc_name += strlen("syscall_exit_");
1970 } else if (!strncmp(desc_name, "syscall_entry_",
1971 strlen("syscall_entry_"))) {
1972 desc_name += strlen("syscall_entry_");
1973 entry = true;
1974 } else {
1975 WARN_ON_ONCE(1);
1976 return -EINVAL;
1977 }
1978 switch (enabler->event_param.u.syscall.entryexit) {
1979 case LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT:
1980 break;
1981 case LTTNG_KERNEL_ABI_SYSCALL_ENTRY:
1982 if (!entry)
1983 return 0;
1984 break;
1985 case LTTNG_KERNEL_ABI_SYSCALL_EXIT:
1986 if (entry)
1987 return 0;
1988 break;
1989 default:
1990 return -EINVAL;
1991 }
1992 switch (enabler->event_param.u.syscall.abi) {
1993 case LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL:
1994 break;
1995 case LTTNG_KERNEL_ABI_SYSCALL_ABI_NATIVE:
1996 if (compat)
1997 return 0;
1998 break;
1999 case LTTNG_KERNEL_ABI_SYSCALL_ABI_COMPAT:
2000 if (!compat)
2001 return 0;
2002 break;
2003 default:
2004 return -EINVAL;
2005 }
2006 switch (enabler->event_param.u.syscall.match) {
2007 case LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME:
2008 switch (enabler->format_type) {
2009 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
2010 return lttng_match_enabler_star_glob(desc_name, enabler_name);
2011 case LTTNG_ENABLER_FORMAT_NAME:
2012 return lttng_match_enabler_name(desc_name, enabler_name);
2013 default:
2014 return -EINVAL;
2015 }
2016 break;
2017 case LTTNG_KERNEL_ABI_SYSCALL_MATCH_NR:
2018 return -EINVAL; /* Not implemented. */
2019 default:
2020 return -EINVAL;
2021 }
2022 break;
2023
2024 default:
2025 WARN_ON_ONCE(1);
2026 return -EINVAL;
2027 }
2028 }
2029
2030 static
2031 int lttng_event_enabler_match_event(struct lttng_event_enabler *event_enabler,
2032 struct lttng_kernel_event_recorder *event_recorder)
2033 {
2034 struct lttng_enabler *base_enabler = lttng_event_enabler_as_enabler(
2035 event_enabler);
2036
2037 if (base_enabler->event_param.instrumentation != event_recorder->priv->parent.instrumentation)
2038 return 0;
2039 if (lttng_desc_match_enabler(event_recorder->priv->parent.desc, base_enabler)
2040 && event_recorder->chan == event_enabler->chan)
2041 return 1;
2042 else
2043 return 0;
2044 }
2045
2046 static
2047 int lttng_event_notifier_enabler_match_event_notifier(struct lttng_event_notifier_enabler *event_notifier_enabler,
2048 struct lttng_kernel_event_notifier *event_notifier)
2049 {
2050 struct lttng_enabler *base_enabler = lttng_event_notifier_enabler_as_enabler(
2051 event_notifier_enabler);
2052
2053 if (base_enabler->event_param.instrumentation != event_notifier->priv->parent.instrumentation)
2054 return 0;
2055 if (lttng_desc_match_enabler(event_notifier->priv->parent.desc, base_enabler)
2056 && event_notifier->priv->group == event_notifier_enabler->group
2057 && event_notifier->priv->parent.user_token == event_notifier_enabler->base.user_token)
2058 return 1;
2059 else
2060 return 0;
2061 }
2062
2063 static
2064 struct lttng_enabler_ref *lttng_enabler_ref(
2065 struct list_head *enablers_ref_list,
2066 struct lttng_enabler *enabler)
2067 {
2068 struct lttng_enabler_ref *enabler_ref;
2069
2070 list_for_each_entry(enabler_ref, enablers_ref_list, node) {
2071 if (enabler_ref->ref == enabler)
2072 return enabler_ref;
2073 }
2074 return NULL;
2075 }
2076
2077 static
2078 void lttng_create_tracepoint_event_if_missing(struct lttng_event_enabler *event_enabler)
2079 {
2080 struct lttng_kernel_session *session = event_enabler->chan->parent.session;
2081 struct lttng_kernel_probe_desc *probe_desc;
2082 const struct lttng_kernel_event_desc *desc;
2083 int i;
2084 struct list_head *probe_list;
2085
2086 probe_list = lttng_get_probe_list_head();
2087 /*
2088 * For each probe event, if we find that a probe event matches
2089 * our enabler, create an associated lttng_event if not
2090 * already present.
2091 */
2092 list_for_each_entry(probe_desc, probe_list, head) {
2093 for (i = 0; i < probe_desc->nr_events; i++) {
2094 int found = 0;
2095 struct hlist_head *head;
2096 struct lttng_kernel_event_recorder_private *event_recorder_private;
2097 struct lttng_kernel_event_recorder *event_recorder;
2098
2099 desc = probe_desc->event_desc[i];
2100 if (!lttng_desc_match_enabler(desc,
2101 lttng_event_enabler_as_enabler(event_enabler)))
2102 continue;
2103
2104 /*
2105 * Check if already created.
2106 */
2107 head = utils_borrow_hash_table_bucket(
2108 session->priv->events_ht.table, LTTNG_EVENT_HT_SIZE,
2109 desc->event_name);
2110 lttng_hlist_for_each_entry(event_recorder_private, head, hlist) {
2111 if (event_recorder_private->parent.desc == desc
2112 && event_recorder_private->pub->chan == event_enabler->chan)
2113 found = 1;
2114 }
2115 if (found)
2116 continue;
2117
2118 /*
2119 * We need to create an event for this
2120 * event probe.
2121 */
2122 event_recorder = _lttng_kernel_event_recorder_create(event_enabler->chan,
2123 NULL, desc, LTTNG_KERNEL_ABI_TRACEPOINT);
2124 if (!event_recorder) {
2125 printk(KERN_INFO "LTTng: Unable to create event %s\n",
2126 probe_desc->event_desc[i]->event_name);
2127 }
2128 }
2129 }
2130 }
2131
2132 static
2133 void lttng_create_tracepoint_event_notifier_if_missing(struct lttng_event_notifier_enabler *event_notifier_enabler)
2134 {
2135 struct lttng_event_notifier_group *event_notifier_group = event_notifier_enabler->group;
2136 struct lttng_kernel_probe_desc *probe_desc;
2137 const struct lttng_kernel_event_desc *desc;
2138 int i;
2139 struct list_head *probe_list;
2140
2141 probe_list = lttng_get_probe_list_head();
2142 /*
2143 * For each probe event, if we find that a probe event matches
2144 * our enabler, create an associated lttng_event_notifier if not
2145 * already present.
2146 */
2147 list_for_each_entry(probe_desc, probe_list, head) {
2148 for (i = 0; i < probe_desc->nr_events; i++) {
2149 int found = 0;
2150 struct hlist_head *head;
2151 struct lttng_kernel_event_notifier_private *event_notifier_priv;
2152 struct lttng_kernel_event_notifier *event_notifier;
2153
2154 desc = probe_desc->event_desc[i];
2155 if (!lttng_desc_match_enabler(desc,
2156 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)))
2157 continue;
2158
2159 /*
2160 * Check if already created.
2161 */
2162 head = utils_borrow_hash_table_bucket(
2163 event_notifier_group->event_notifiers_ht.table,
2164 LTTNG_EVENT_NOTIFIER_HT_SIZE, desc->event_name);
2165 lttng_hlist_for_each_entry(event_notifier_priv, head, hlist) {
2166 if (event_notifier_priv->parent.desc == desc
2167 && event_notifier_priv->parent.user_token == event_notifier_enabler->base.user_token)
2168 found = 1;
2169 }
2170 if (found)
2171 continue;
2172
2173 /*
2174 * We need to create a event_notifier for this event probe.
2175 */
2176 event_notifier = _lttng_event_notifier_create(desc,
2177 event_notifier_enabler->base.user_token,
2178 event_notifier_enabler->error_counter_index,
2179 event_notifier_group, NULL,
2180 LTTNG_KERNEL_ABI_TRACEPOINT);
2181 if (IS_ERR(event_notifier)) {
2182 printk(KERN_INFO "Unable to create event_notifier %s\n",
2183 probe_desc->event_desc[i]->event_name);
2184 }
2185 }
2186 }
2187 }
2188
2189 static
2190 void lttng_create_syscall_event_if_missing(struct lttng_event_enabler *event_enabler)
2191 {
2192 int ret;
2193
2194 ret = lttng_syscalls_register_event(event_enabler);
2195 WARN_ON_ONCE(ret);
2196 }
2197
2198 static
2199 void lttng_create_syscall_event_notifier_if_missing(struct lttng_event_notifier_enabler *event_notifier_enabler)
2200 {
2201 int ret;
2202
2203 ret = lttng_syscalls_register_event_notifier(event_notifier_enabler);
2204 WARN_ON_ONCE(ret);
2205 ret = lttng_syscalls_create_matching_event_notifiers(event_notifier_enabler);
2206 WARN_ON_ONCE(ret);
2207 }
2208
2209 /*
2210 * Create struct lttng_kernel_event_recorder if it is missing and present in the list of
2211 * tracepoint probes.
2212 * Should be called with sessions mutex held.
2213 */
2214 static
2215 void lttng_create_event_if_missing(struct lttng_event_enabler *event_enabler)
2216 {
2217 switch (event_enabler->base.event_param.instrumentation) {
2218 case LTTNG_KERNEL_ABI_TRACEPOINT:
2219 lttng_create_tracepoint_event_if_missing(event_enabler);
2220 break;
2221
2222 case LTTNG_KERNEL_ABI_SYSCALL:
2223 lttng_create_syscall_event_if_missing(event_enabler);
2224 break;
2225
2226 default:
2227 WARN_ON_ONCE(1);
2228 break;
2229 }
2230 }
2231
2232 /*
2233 * Create events associated with an event_enabler (if not already present),
2234 * and add backward reference from the event to the enabler.
2235 * Should be called with sessions mutex held.
2236 */
2237 static
2238 int lttng_event_enabler_ref_events(struct lttng_event_enabler *event_enabler)
2239 {
2240 struct lttng_kernel_channel_buffer *chan = event_enabler->chan;
2241 struct lttng_kernel_session *session = event_enabler->chan->parent.session;
2242 struct lttng_enabler *base_enabler = lttng_event_enabler_as_enabler(event_enabler);
2243 struct lttng_kernel_event_recorder_private *event_recorder_priv;
2244
2245 if (base_enabler->event_param.instrumentation == LTTNG_KERNEL_ABI_SYSCALL &&
2246 base_enabler->event_param.u.syscall.abi == LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL &&
2247 base_enabler->event_param.u.syscall.match == LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME &&
2248 !strcmp(base_enabler->event_param.name, "*")) {
2249 int enabled = base_enabler->enabled;
2250 enum lttng_kernel_abi_syscall_entryexit entryexit = base_enabler->event_param.u.syscall.entryexit;
2251
2252 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRY || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2253 WRITE_ONCE(chan->priv->parent.syscall_all_entry, enabled);
2254
2255 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_EXIT || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2256 WRITE_ONCE(chan->priv->parent.syscall_all_exit, enabled);
2257 }
2258
2259 /* First ensure that probe events are created for this enabler. */
2260 lttng_create_event_if_missing(event_enabler);
2261
2262 /* For each event matching event_enabler in session event list. */
2263 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
2264 struct lttng_kernel_event_recorder *event_recorder = event_recorder_priv->pub;
2265 struct lttng_enabler_ref *enabler_ref;
2266
2267 if (!lttng_event_enabler_match_event(event_enabler, event_recorder))
2268 continue;
2269 enabler_ref = lttng_enabler_ref(&event_recorder_priv->parent.enablers_ref_head,
2270 lttng_event_enabler_as_enabler(event_enabler));
2271 if (!enabler_ref) {
2272 /*
2273 * If no backward ref, create it.
2274 * Add backward ref from event to event_enabler.
2275 */
2276 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
2277 if (!enabler_ref)
2278 return -ENOMEM;
2279 enabler_ref->ref = lttng_event_enabler_as_enabler(event_enabler);
2280 list_add(&enabler_ref->node,
2281 &event_recorder_priv->parent.enablers_ref_head);
2282 }
2283
2284 /*
2285 * Link filter bytecodes if not linked yet.
2286 */
2287 lttng_enabler_link_bytecode(event_recorder_priv->parent.desc,
2288 lttng_static_ctx,
2289 &event_recorder_priv->parent.filter_bytecode_runtime_head,
2290 &lttng_event_enabler_as_enabler(event_enabler)->filter_bytecode_head);
2291 }
2292 return 0;
2293 }
2294
2295 /*
2296 * Create struct lttng_kernel_event_notifier if it is missing and present in the list of
2297 * tracepoint probes.
2298 * Should be called with sessions mutex held.
2299 */
2300 static
2301 void lttng_create_event_notifier_if_missing(struct lttng_event_notifier_enabler *event_notifier_enabler)
2302 {
2303 switch (event_notifier_enabler->base.event_param.instrumentation) {
2304 case LTTNG_KERNEL_ABI_TRACEPOINT:
2305 lttng_create_tracepoint_event_notifier_if_missing(event_notifier_enabler);
2306 break;
2307
2308 case LTTNG_KERNEL_ABI_SYSCALL:
2309 lttng_create_syscall_event_notifier_if_missing(event_notifier_enabler);
2310 break;
2311
2312 default:
2313 WARN_ON_ONCE(1);
2314 break;
2315 }
2316 }
2317
2318 /*
2319 * Create event_notifiers associated with a event_notifier enabler (if not already present).
2320 */
2321 static
2322 int lttng_event_notifier_enabler_ref_event_notifiers(
2323 struct lttng_event_notifier_enabler *event_notifier_enabler)
2324 {
2325 struct lttng_event_notifier_group *event_notifier_group = event_notifier_enabler->group;
2326 struct lttng_enabler *base_enabler = lttng_event_notifier_enabler_as_enabler(event_notifier_enabler);
2327 struct lttng_kernel_event_notifier_private *event_notifier_priv;
2328
2329 if (base_enabler->event_param.instrumentation == LTTNG_KERNEL_ABI_SYSCALL &&
2330 base_enabler->event_param.u.syscall.abi == LTTNG_KERNEL_ABI_SYSCALL_ABI_ALL &&
2331 base_enabler->event_param.u.syscall.match == LTTNG_KERNEL_ABI_SYSCALL_MATCH_NAME &&
2332 !strcmp(base_enabler->event_param.name, "*")) {
2333
2334 int enabled = base_enabler->enabled;
2335 enum lttng_kernel_abi_syscall_entryexit entryexit = base_enabler->event_param.u.syscall.entryexit;
2336
2337 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRY || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2338 WRITE_ONCE(event_notifier_group->syscall_all_entry, enabled);
2339
2340 if (entryexit == LTTNG_KERNEL_ABI_SYSCALL_EXIT || entryexit == LTTNG_KERNEL_ABI_SYSCALL_ENTRYEXIT)
2341 WRITE_ONCE(event_notifier_group->syscall_all_exit, enabled);
2342
2343 }
2344
2345 /* First ensure that probe event_notifiers are created for this enabler. */
2346 lttng_create_event_notifier_if_missing(event_notifier_enabler);
2347
2348 /* Link the created event_notifier with its associated enabler. */
2349 list_for_each_entry(event_notifier_priv, &event_notifier_group->event_notifiers_head, node) {
2350 struct lttng_kernel_event_notifier *event_notifier = event_notifier_priv->pub;
2351 struct lttng_enabler_ref *enabler_ref;
2352
2353 if (!lttng_event_notifier_enabler_match_event_notifier(event_notifier_enabler, event_notifier))
2354 continue;
2355
2356 enabler_ref = lttng_enabler_ref(&event_notifier_priv->parent.enablers_ref_head,
2357 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler));
2358 if (!enabler_ref) {
2359 /*
2360 * If no backward ref, create it.
2361 * Add backward ref from event_notifier to enabler.
2362 */
2363 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
2364 if (!enabler_ref)
2365 return -ENOMEM;
2366
2367 enabler_ref->ref = lttng_event_notifier_enabler_as_enabler(
2368 event_notifier_enabler);
2369 list_add(&enabler_ref->node,
2370 &event_notifier_priv->parent.enablers_ref_head);
2371 }
2372
2373 /*
2374 * Link filter bytecodes if not linked yet.
2375 */
2376 lttng_enabler_link_bytecode(event_notifier_priv->parent.desc,
2377 lttng_static_ctx, &event_notifier_priv->parent.filter_bytecode_runtime_head,
2378 &lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->filter_bytecode_head);
2379
2380 /* Link capture bytecodes if not linked yet. */
2381 lttng_enabler_link_bytecode(event_notifier_priv->parent.desc,
2382 lttng_static_ctx, &event_notifier_priv->capture_bytecode_runtime_head,
2383 &event_notifier_enabler->capture_bytecode_head);
2384
2385 event_notifier_priv->num_captures = event_notifier_enabler->num_captures;
2386 }
2387 return 0;
2388 }
2389
2390 /*
2391 * Called at module load: connect the probe on all enablers matching
2392 * this event.
2393 * Called with sessions lock held.
2394 */
2395 int lttng_fix_pending_events(void)
2396 {
2397 struct lttng_kernel_session_private *session_priv;
2398
2399 list_for_each_entry(session_priv, &sessions, list)
2400 lttng_session_lazy_sync_event_enablers(session_priv->pub);
2401 return 0;
2402 }
2403
2404 static bool lttng_event_notifier_group_has_active_event_notifiers(
2405 struct lttng_event_notifier_group *event_notifier_group)
2406 {
2407 struct lttng_event_notifier_enabler *event_notifier_enabler;
2408
2409 list_for_each_entry(event_notifier_enabler, &event_notifier_group->enablers_head,
2410 node) {
2411 if (event_notifier_enabler->base.enabled)
2412 return true;
2413 }
2414 return false;
2415 }
2416
2417 bool lttng_event_notifier_active(void)
2418 {
2419 struct lttng_event_notifier_group *event_notifier_group;
2420
2421 list_for_each_entry(event_notifier_group, &event_notifier_groups, node) {
2422 if (lttng_event_notifier_group_has_active_event_notifiers(event_notifier_group))
2423 return true;
2424 }
2425 return false;
2426 }
2427
2428 int lttng_fix_pending_event_notifiers(void)
2429 {
2430 struct lttng_event_notifier_group *event_notifier_group;
2431
2432 list_for_each_entry(event_notifier_group, &event_notifier_groups, node)
2433 lttng_event_notifier_group_sync_enablers(event_notifier_group);
2434 return 0;
2435 }
2436
2437 struct lttng_event_enabler *lttng_event_enabler_create(
2438 enum lttng_enabler_format_type format_type,
2439 struct lttng_kernel_abi_event *event_param,
2440 struct lttng_kernel_channel_buffer *chan)
2441 {
2442 struct lttng_event_enabler *event_enabler;
2443
2444 event_enabler = kzalloc(sizeof(*event_enabler), GFP_KERNEL);
2445 if (!event_enabler)
2446 return NULL;
2447 event_enabler->base.format_type = format_type;
2448 INIT_LIST_HEAD(&event_enabler->base.filter_bytecode_head);
2449 memcpy(&event_enabler->base.event_param, event_param,
2450 sizeof(event_enabler->base.event_param));
2451 event_enabler->chan = chan;
2452 /* ctx left NULL */
2453 event_enabler->base.enabled = 0;
2454 mutex_lock(&sessions_mutex);
2455 list_add(&event_enabler->node, &event_enabler->chan->parent.session->priv->enablers_head);
2456 lttng_session_lazy_sync_event_enablers(event_enabler->chan->parent.session);
2457 mutex_unlock(&sessions_mutex);
2458 return event_enabler;
2459 }
2460
2461 int lttng_event_enabler_enable(struct lttng_event_enabler *event_enabler)
2462 {
2463 mutex_lock(&sessions_mutex);
2464 lttng_event_enabler_as_enabler(event_enabler)->enabled = 1;
2465 lttng_session_lazy_sync_event_enablers(event_enabler->chan->parent.session);
2466 mutex_unlock(&sessions_mutex);
2467 return 0;
2468 }
2469
2470 int lttng_event_enabler_disable(struct lttng_event_enabler *event_enabler)
2471 {
2472 mutex_lock(&sessions_mutex);
2473 lttng_event_enabler_as_enabler(event_enabler)->enabled = 0;
2474 lttng_session_lazy_sync_event_enablers(event_enabler->chan->parent.session);
2475 mutex_unlock(&sessions_mutex);
2476 return 0;
2477 }
2478
2479 static
2480 int lttng_enabler_attach_filter_bytecode(struct lttng_enabler *enabler,
2481 struct lttng_kernel_abi_filter_bytecode __user *bytecode)
2482 {
2483 struct lttng_kernel_bytecode_node *bytecode_node;
2484 uint32_t bytecode_len;
2485 int ret;
2486
2487 ret = get_user(bytecode_len, &bytecode->len);
2488 if (ret)
2489 return ret;
2490 bytecode_node = lttng_kvzalloc(sizeof(*bytecode_node) + bytecode_len,
2491 GFP_KERNEL);
2492 if (!bytecode_node)
2493 return -ENOMEM;
2494 ret = copy_from_user(&bytecode_node->bc, bytecode,
2495 sizeof(*bytecode) + bytecode_len);
2496 if (ret)
2497 goto error_free;
2498
2499 bytecode_node->type = LTTNG_KERNEL_BYTECODE_TYPE_FILTER;
2500 bytecode_node->enabler = enabler;
2501 /* Enforce length based on allocated size */
2502 bytecode_node->bc.len = bytecode_len;
2503 list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head);
2504
2505 return 0;
2506
2507 error_free:
2508 lttng_kvfree(bytecode_node);
2509 return ret;
2510 }
2511
2512 int lttng_event_enabler_attach_filter_bytecode(struct lttng_event_enabler *event_enabler,
2513 struct lttng_kernel_abi_filter_bytecode __user *bytecode)
2514 {
2515 int ret;
2516 ret = lttng_enabler_attach_filter_bytecode(
2517 lttng_event_enabler_as_enabler(event_enabler), bytecode);
2518 if (ret)
2519 goto error;
2520
2521 lttng_session_lazy_sync_event_enablers(event_enabler->chan->parent.session);
2522 return 0;
2523
2524 error:
2525 return ret;
2526 }
2527
2528 int lttng_event_add_callsite(struct lttng_kernel_event_common *event,
2529 struct lttng_kernel_abi_event_callsite __user *callsite)
2530 {
2531
2532 switch (event->priv->instrumentation) {
2533 case LTTNG_KERNEL_ABI_UPROBE:
2534 return lttng_uprobes_event_add_callsite(event, callsite);
2535 default:
2536 return -EINVAL;
2537 }
2538 }
2539
2540 static
2541 void lttng_enabler_destroy(struct lttng_enabler *enabler)
2542 {
2543 struct lttng_kernel_bytecode_node *filter_node, *tmp_filter_node;
2544
2545 /* Destroy filter bytecode */
2546 list_for_each_entry_safe(filter_node, tmp_filter_node,
2547 &enabler->filter_bytecode_head, node) {
2548 lttng_kvfree(filter_node);
2549 }
2550 }
2551
2552 static
2553 void lttng_event_enabler_destroy(struct lttng_event_enabler *event_enabler)
2554 {
2555 lttng_enabler_destroy(lttng_event_enabler_as_enabler(event_enabler));
2556
2557 list_del(&event_enabler->node);
2558 kfree(event_enabler);
2559 }
2560
2561 struct lttng_event_notifier_enabler *lttng_event_notifier_enabler_create(
2562 struct lttng_event_notifier_group *event_notifier_group,
2563 enum lttng_enabler_format_type format_type,
2564 struct lttng_kernel_abi_event_notifier *event_notifier_param)
2565 {
2566 struct lttng_event_notifier_enabler *event_notifier_enabler;
2567
2568 event_notifier_enabler = kzalloc(sizeof(*event_notifier_enabler), GFP_KERNEL);
2569 if (!event_notifier_enabler)
2570 return NULL;
2571
2572 event_notifier_enabler->base.format_type = format_type;
2573 INIT_LIST_HEAD(&event_notifier_enabler->base.filter_bytecode_head);
2574 INIT_LIST_HEAD(&event_notifier_enabler->capture_bytecode_head);
2575
2576 event_notifier_enabler->error_counter_index = event_notifier_param->error_counter_index;
2577 event_notifier_enabler->num_captures = 0;
2578
2579 memcpy(&event_notifier_enabler->base.event_param, &event_notifier_param->event,
2580 sizeof(event_notifier_enabler->base.event_param));
2581
2582 event_notifier_enabler->base.enabled = 0;
2583 event_notifier_enabler->base.user_token = event_notifier_param->event.token;
2584 event_notifier_enabler->group = event_notifier_group;
2585
2586 mutex_lock(&sessions_mutex);
2587 list_add(&event_notifier_enabler->node, &event_notifier_enabler->group->enablers_head);
2588 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2589
2590 mutex_unlock(&sessions_mutex);
2591
2592 return event_notifier_enabler;
2593 }
2594
2595 int lttng_event_notifier_enabler_enable(
2596 struct lttng_event_notifier_enabler *event_notifier_enabler)
2597 {
2598 mutex_lock(&sessions_mutex);
2599 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->enabled = 1;
2600 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2601 mutex_unlock(&sessions_mutex);
2602 return 0;
2603 }
2604
2605 int lttng_event_notifier_enabler_disable(
2606 struct lttng_event_notifier_enabler *event_notifier_enabler)
2607 {
2608 mutex_lock(&sessions_mutex);
2609 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler)->enabled = 0;
2610 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2611 mutex_unlock(&sessions_mutex);
2612 return 0;
2613 }
2614
2615 int lttng_event_notifier_enabler_attach_filter_bytecode(
2616 struct lttng_event_notifier_enabler *event_notifier_enabler,
2617 struct lttng_kernel_abi_filter_bytecode __user *bytecode)
2618 {
2619 int ret;
2620
2621 ret = lttng_enabler_attach_filter_bytecode(
2622 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler),
2623 bytecode);
2624 if (ret)
2625 goto error;
2626
2627 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2628 return 0;
2629
2630 error:
2631 return ret;
2632 }
2633
2634 int lttng_event_notifier_enabler_attach_capture_bytecode(
2635 struct lttng_event_notifier_enabler *event_notifier_enabler,
2636 struct lttng_kernel_abi_capture_bytecode __user *bytecode)
2637 {
2638 struct lttng_kernel_bytecode_node *bytecode_node;
2639 struct lttng_enabler *enabler =
2640 lttng_event_notifier_enabler_as_enabler(event_notifier_enabler);
2641 uint32_t bytecode_len;
2642 int ret;
2643
2644 ret = get_user(bytecode_len, &bytecode->len);
2645 if (ret)
2646 return ret;
2647
2648 bytecode_node = lttng_kvzalloc(sizeof(*bytecode_node) + bytecode_len,
2649 GFP_KERNEL);
2650 if (!bytecode_node)
2651 return -ENOMEM;
2652
2653 ret = copy_from_user(&bytecode_node->bc, bytecode,
2654 sizeof(*bytecode) + bytecode_len);
2655 if (ret)
2656 goto error_free;
2657
2658 bytecode_node->type = LTTNG_KERNEL_BYTECODE_TYPE_CAPTURE;
2659 bytecode_node->enabler = enabler;
2660
2661 /* Enforce length based on allocated size */
2662 bytecode_node->bc.len = bytecode_len;
2663 list_add_tail(&bytecode_node->node, &event_notifier_enabler->capture_bytecode_head);
2664
2665 event_notifier_enabler->num_captures++;
2666
2667 lttng_event_notifier_group_sync_enablers(event_notifier_enabler->group);
2668 goto end;
2669
2670 error_free:
2671 lttng_kvfree(bytecode_node);
2672 end:
2673 return ret;
2674 }
2675
2676 static
2677 void lttng_event_notifier_enabler_destroy(
2678 struct lttng_event_notifier_enabler *event_notifier_enabler)
2679 {
2680 if (!event_notifier_enabler) {
2681 return;
2682 }
2683
2684 list_del(&event_notifier_enabler->node);
2685
2686 lttng_enabler_destroy(lttng_event_notifier_enabler_as_enabler(event_notifier_enabler));
2687 kfree(event_notifier_enabler);
2688 }
2689
2690 /*
2691 * lttng_session_sync_event_enablers should be called just before starting a
2692 * session.
2693 * Should be called with sessions mutex held.
2694 */
2695 static
2696 void lttng_session_sync_event_enablers(struct lttng_kernel_session *session)
2697 {
2698 struct lttng_event_enabler *event_enabler;
2699 struct lttng_kernel_event_recorder_private *event_recorder_priv;
2700
2701 list_for_each_entry(event_enabler, &session->priv->enablers_head, node)
2702 lttng_event_enabler_ref_events(event_enabler);
2703 /*
2704 * For each event, if at least one of its enablers is enabled,
2705 * and its channel and session transient states are enabled, we
2706 * enable the event, else we disable it.
2707 */
2708 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
2709 struct lttng_kernel_event_recorder *event_recorder = event_recorder_priv->pub;
2710 struct lttng_enabler_ref *enabler_ref;
2711 struct lttng_kernel_bytecode_runtime *runtime;
2712 int enabled = 0, has_enablers_without_filter_bytecode = 0;
2713 int nr_filters = 0;
2714
2715 switch (event_recorder_priv->parent.instrumentation) {
2716 case LTTNG_KERNEL_ABI_TRACEPOINT: /* Fall-through */
2717 case LTTNG_KERNEL_ABI_SYSCALL:
2718 /* Enable events */
2719 list_for_each_entry(enabler_ref,
2720 &event_recorder_priv->parent.enablers_ref_head, node) {
2721 if (enabler_ref->ref->enabled) {
2722 enabled = 1;
2723 break;
2724 }
2725 }
2726 break;
2727
2728 default:
2729 /* Not handled with lazy sync. */
2730 continue;
2731 }
2732 /*
2733 * Enabled state is based on union of enablers, with
2734 * intesection of session and channel transient enable
2735 * states.
2736 */
2737 enabled = enabled && session->priv->tstate && event_recorder->chan->priv->parent.tstate;
2738
2739 WRITE_ONCE(event_recorder->parent.enabled, enabled);
2740 /*
2741 * Sync tracepoint registration with event enabled
2742 * state.
2743 */
2744 if (enabled) {
2745 register_event(event_recorder);
2746 } else {
2747 _lttng_event_unregister(event_recorder);
2748 }
2749
2750 /* Check if has enablers without bytecode enabled */
2751 list_for_each_entry(enabler_ref,
2752 &event_recorder_priv->parent.enablers_ref_head, node) {
2753 if (enabler_ref->ref->enabled
2754 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
2755 has_enablers_without_filter_bytecode = 1;
2756 break;
2757 }
2758 }
2759 event_recorder_priv->parent.has_enablers_without_filter_bytecode =
2760 has_enablers_without_filter_bytecode;
2761
2762 /* Enable filters */
2763 list_for_each_entry(runtime,
2764 &event_recorder_priv->parent.filter_bytecode_runtime_head, node) {
2765 lttng_bytecode_sync_state(runtime);
2766 nr_filters++;
2767 }
2768 WRITE_ONCE(event_recorder_priv->parent.pub->eval_filter,
2769 !(has_enablers_without_filter_bytecode || !nr_filters));
2770 }
2771 }
2772
2773 /*
2774 * Apply enablers to session events, adding events to session if need
2775 * be. It is required after each modification applied to an active
2776 * session, and right before session "start".
2777 * "lazy" sync means we only sync if required.
2778 * Should be called with sessions mutex held.
2779 */
2780 static
2781 void lttng_session_lazy_sync_event_enablers(struct lttng_kernel_session *session)
2782 {
2783 /* We can skip if session is not active */
2784 if (!session->active)
2785 return;
2786 lttng_session_sync_event_enablers(session);
2787 }
2788
2789 static
2790 void lttng_event_notifier_group_sync_enablers(struct lttng_event_notifier_group *event_notifier_group)
2791 {
2792 struct lttng_event_notifier_enabler *event_notifier_enabler;
2793 struct lttng_kernel_event_notifier_private *event_notifier_priv;
2794
2795 list_for_each_entry(event_notifier_enabler, &event_notifier_group->enablers_head, node)
2796 lttng_event_notifier_enabler_ref_event_notifiers(event_notifier_enabler);
2797
2798 /*
2799 * For each event_notifier, if at least one of its enablers is enabled,
2800 * we enable the event_notifier, else we disable it.
2801 */
2802 list_for_each_entry(event_notifier_priv, &event_notifier_group->event_notifiers_head, node) {
2803 struct lttng_kernel_event_notifier *event_notifier = event_notifier_priv->pub;
2804 struct lttng_enabler_ref *enabler_ref;
2805 struct lttng_kernel_bytecode_runtime *runtime;
2806 int enabled = 0, has_enablers_without_filter_bytecode = 0;
2807 int nr_filters = 0, nr_captures = 0;
2808
2809 switch (event_notifier_priv->parent.instrumentation) {
2810 case LTTNG_KERNEL_ABI_TRACEPOINT: /* Fall-through */
2811 case LTTNG_KERNEL_ABI_SYSCALL:
2812 /* Enable event_notifiers */
2813 list_for_each_entry(enabler_ref,
2814 &event_notifier_priv->parent.enablers_ref_head, node) {
2815 if (enabler_ref->ref->enabled) {
2816 enabled = 1;
2817 break;
2818 }
2819 }
2820 break;
2821
2822 default:
2823 /* Not handled with sync. */
2824 continue;
2825 }
2826
2827 WRITE_ONCE(event_notifier->parent.enabled, enabled);
2828 /*
2829 * Sync tracepoint registration with event_notifier enabled
2830 * state.
2831 */
2832 if (enabled) {
2833 if (!event_notifier_priv->parent.registered)
2834 register_event_notifier(event_notifier);
2835 } else {
2836 if (event_notifier_priv->parent.registered)
2837 _lttng_event_notifier_unregister(event_notifier);
2838 }
2839
2840 /* Check if has enablers without bytecode enabled */
2841 list_for_each_entry(enabler_ref,
2842 &event_notifier_priv->parent.enablers_ref_head, node) {
2843 if (enabler_ref->ref->enabled
2844 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
2845 has_enablers_without_filter_bytecode = 1;
2846 break;
2847 }
2848 }
2849 event_notifier_priv->parent.has_enablers_without_filter_bytecode =
2850 has_enablers_without_filter_bytecode;
2851
2852 /* Enable filters */
2853 list_for_each_entry(runtime,
2854 &event_notifier_priv->parent.filter_bytecode_runtime_head, node) {
2855 lttng_bytecode_sync_state(runtime);
2856 nr_filters++;
2857 }
2858 WRITE_ONCE(event_notifier_priv->parent.pub->eval_filter,
2859 !(has_enablers_without_filter_bytecode || !nr_filters));
2860
2861 /* Enable captures */
2862 list_for_each_entry(runtime,
2863 &event_notifier_priv->capture_bytecode_runtime_head, node) {
2864 lttng_bytecode_sync_state(runtime);
2865 nr_captures++;
2866 }
2867 WRITE_ONCE(event_notifier->eval_capture, !!nr_captures);
2868 }
2869 }
2870
2871 /*
2872 * Serialize at most one packet worth of metadata into a metadata
2873 * channel.
2874 * We grab the metadata cache mutex to get exclusive access to our metadata
2875 * buffer and to the metadata cache. Exclusive access to the metadata buffer
2876 * allows us to do racy operations such as looking for remaining space left in
2877 * packet and write, since mutual exclusion protects us from concurrent writes.
2878 * Mutual exclusion on the metadata cache allow us to read the cache content
2879 * without racing against reallocation of the cache by updates.
2880 * Returns the number of bytes written in the channel, 0 if no data
2881 * was written and a negative value on error.
2882 */
2883 int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
2884 struct lttng_kernel_ring_buffer_channel *chan, bool *coherent)
2885 {
2886 struct lttng_kernel_ring_buffer_ctx ctx;
2887 int ret = 0;
2888 size_t len, reserve_len;
2889
2890 /*
2891 * Ensure we support mutiple get_next / put sequences followed by
2892 * put_next. The metadata cache lock protects reading the metadata
2893 * cache. It can indeed be read concurrently by "get_next_subbuf" and
2894 * "flush" operations on the buffer invoked by different processes.
2895 * Moreover, since the metadata cache memory can be reallocated, we
2896 * need to have exclusive access against updates even though we only
2897 * read it.
2898 */
2899 mutex_lock(&stream->metadata_cache->lock);
2900 WARN_ON(stream->metadata_in < stream->metadata_out);
2901 if (stream->metadata_in != stream->metadata_out)
2902 goto end;
2903
2904 /* Metadata regenerated, change the version. */
2905 if (stream->metadata_cache->version != stream->version)
2906 stream->version = stream->metadata_cache->version;
2907
2908 len = stream->metadata_cache->metadata_written -
2909 stream->metadata_in;
2910 if (!len)
2911 goto end;
2912 reserve_len = min_t(size_t,
2913 stream->transport->ops.priv->packet_avail_size(chan),
2914 len);
2915 lib_ring_buffer_ctx_init(&ctx, chan, reserve_len,
2916 sizeof(char), NULL);
2917 /*
2918 * If reservation failed, return an error to the caller.
2919 */
2920 ret = stream->transport->ops.event_reserve(&ctx);
2921 if (ret != 0) {
2922 printk(KERN_WARNING "LTTng: Metadata event reservation failed\n");
2923 stream->coherent = false;
2924 goto end;
2925 }
2926 stream->transport->ops.event_write(&ctx,
2927 stream->metadata_cache->data + stream->metadata_in,
2928 reserve_len, 1);
2929 stream->transport->ops.event_commit(&ctx);
2930 stream->metadata_in += reserve_len;
2931 if (reserve_len < len)
2932 stream->coherent = false;
2933 else
2934 stream->coherent = true;
2935 ret = reserve_len;
2936
2937 end:
2938 if (coherent)
2939 *coherent = stream->coherent;
2940 mutex_unlock(&stream->metadata_cache->lock);
2941 return ret;
2942 }
2943
2944 static
2945 void lttng_metadata_begin(struct lttng_kernel_session *session)
2946 {
2947 if (atomic_inc_return(&session->priv->metadata_cache->producing) == 1)
2948 mutex_lock(&session->priv->metadata_cache->lock);
2949 }
2950
2951 static
2952 void lttng_metadata_end(struct lttng_kernel_session *session)
2953 {
2954 WARN_ON_ONCE(!atomic_read(&session->priv->metadata_cache->producing));
2955 if (atomic_dec_return(&session->priv->metadata_cache->producing) == 0) {
2956 struct lttng_metadata_stream *stream;
2957
2958 list_for_each_entry(stream, &session->priv->metadata_cache->metadata_stream, list)
2959 wake_up_interruptible(&stream->read_wait);
2960 mutex_unlock(&session->priv->metadata_cache->lock);
2961 }
2962 }
2963
2964 /*
2965 * Write the metadata to the metadata cache.
2966 * Must be called with sessions_mutex held.
2967 * The metadata cache lock protects us from concurrent read access from
2968 * thread outputting metadata content to ring buffer.
2969 * The content of the printf is printed as a single atomic metadata
2970 * transaction.
2971 */
2972 int lttng_metadata_printf(struct lttng_kernel_session *session,
2973 const char *fmt, ...)
2974 {
2975 char *str;
2976 size_t len;
2977 va_list ap;
2978
2979 WARN_ON_ONCE(!LTTNG_READ_ONCE(session->active));
2980
2981 va_start(ap, fmt);
2982 str = kvasprintf(GFP_KERNEL, fmt, ap);
2983 va_end(ap);
2984 if (!str)
2985 return -ENOMEM;
2986
2987 len = strlen(str);
2988 WARN_ON_ONCE(!atomic_read(&session->priv->metadata_cache->producing));
2989 if (session->priv->metadata_cache->metadata_written + len >
2990 session->priv->metadata_cache->cache_alloc) {
2991 char *tmp_cache_realloc;
2992 unsigned int tmp_cache_alloc_size;
2993
2994 tmp_cache_alloc_size = max_t(unsigned int,
2995 session->priv->metadata_cache->cache_alloc + len,
2996 session->priv->metadata_cache->cache_alloc << 1);
2997 tmp_cache_realloc = vzalloc(tmp_cache_alloc_size);
2998 if (!tmp_cache_realloc)
2999 goto err;
3000 if (session->priv->metadata_cache->data) {
3001 memcpy(tmp_cache_realloc,
3002 session->priv->metadata_cache->data,
3003 session->priv->metadata_cache->cache_alloc);
3004 vfree(session->priv->metadata_cache->data);
3005 }
3006
3007 session->priv->metadata_cache->cache_alloc = tmp_cache_alloc_size;
3008 session->priv->metadata_cache->data = tmp_cache_realloc;
3009 }
3010 memcpy(session->priv->metadata_cache->data +
3011 session->priv->metadata_cache->metadata_written,
3012 str, len);
3013 session->priv->metadata_cache->metadata_written += len;
3014 kfree(str);
3015
3016 return 0;
3017
3018 err:
3019 kfree(str);
3020 return -ENOMEM;
3021 }
3022
3023 static
3024 int print_tabs(struct lttng_kernel_session *session, size_t nesting)
3025 {
3026 size_t i;
3027
3028 for (i = 0; i < nesting; i++) {
3029 int ret;
3030
3031 ret = lttng_metadata_printf(session, " ");
3032 if (ret) {
3033 return ret;
3034 }
3035 }
3036 return 0;
3037 }
3038
3039 static
3040 int lttng_field_name_statedump(struct lttng_kernel_session *session,
3041 const struct lttng_kernel_event_field *field,
3042 size_t nesting)
3043 {
3044 return lttng_metadata_printf(session, " _%s;\n", field->name);
3045 }
3046
3047 static
3048 int _lttng_integer_type_statedump(struct lttng_kernel_session *session,
3049 const struct lttng_kernel_type_integer *type,
3050 enum lttng_kernel_string_encoding parent_encoding,
3051 size_t nesting)
3052 {
3053 int ret;
3054
3055 ret = print_tabs(session, nesting);
3056 if (ret)
3057 return ret;
3058 ret = lttng_metadata_printf(session,
3059 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s }",
3060 type->size,
3061 type->alignment,
3062 type->signedness,
3063 (parent_encoding == lttng_kernel_string_encoding_none)
3064 ? "none"
3065 : (parent_encoding == lttng_kernel_string_encoding_UTF8)
3066 ? "UTF8"
3067 : "ASCII",
3068 type->base,
3069 #if __BYTE_ORDER == __BIG_ENDIAN
3070 type->reverse_byte_order ? " byte_order = le;" : ""
3071 #else
3072 type->reverse_byte_order ? " byte_order = be;" : ""
3073 #endif
3074 );
3075 return ret;
3076 }
3077
3078 /*
3079 * Must be called with sessions_mutex held.
3080 */
3081 static
3082 int _lttng_struct_type_statedump(struct lttng_kernel_session *session,
3083 const struct lttng_kernel_type_struct *type,
3084 size_t nesting)
3085 {
3086 const char *prev_field_name = NULL;
3087 int ret;
3088 uint32_t i, nr_fields;
3089 unsigned int alignment;
3090
3091 ret = print_tabs(session, nesting);
3092 if (ret)
3093 return ret;
3094 ret = lttng_metadata_printf(session,
3095 "struct {\n");
3096 if (ret)
3097 return ret;
3098 nr_fields = type->nr_fields;
3099 for (i = 0; i < nr_fields; i++) {
3100 const struct lttng_kernel_event_field *iter_field;
3101
3102 iter_field = type->fields[i];
3103 ret = _lttng_field_statedump(session, iter_field, nesting + 1, &prev_field_name);
3104 if (ret)
3105 return ret;
3106 }
3107 ret = print_tabs(session, nesting);
3108 if (ret)
3109 return ret;
3110 alignment = type->alignment;
3111 if (alignment) {
3112 ret = lttng_metadata_printf(session,
3113 "} align(%u)",
3114 alignment);
3115 } else {
3116 ret = lttng_metadata_printf(session,
3117 "}");
3118 }
3119 return ret;
3120 }
3121
3122 /*
3123 * Must be called with sessions_mutex held.
3124 */
3125 static
3126 int _lttng_struct_field_statedump(struct lttng_kernel_session *session,
3127 const struct lttng_kernel_event_field *field,
3128 size_t nesting)
3129 {
3130 int ret;
3131
3132 ret = _lttng_struct_type_statedump(session,
3133 lttng_kernel_get_type_struct(field->type), nesting);
3134 if (ret)
3135 return ret;
3136 return lttng_field_name_statedump(session, field, nesting);
3137 }
3138
3139 /*
3140 * Must be called with sessions_mutex held.
3141 */
3142 static
3143 int _lttng_variant_type_statedump(struct lttng_kernel_session *session,
3144 const struct lttng_kernel_type_variant *type,
3145 size_t nesting,
3146 const char *prev_field_name)
3147 {
3148 const char *tag_name;
3149 int ret;
3150 uint32_t i, nr_choices;
3151
3152 tag_name = type->tag_name;
3153 if (!tag_name)
3154 tag_name = prev_field_name;
3155 if (!tag_name)
3156 return -EINVAL;
3157 /*
3158 * CTF 1.8 does not allow expressing nonzero variant alignment in a nestable way.
3159 */
3160 if (type->alignment != 0)
3161 return -EINVAL;
3162 ret = print_tabs(session, nesting);
3163 if (ret)
3164 return ret;
3165 ret = lttng_metadata_printf(session,
3166 "variant <_%s> {\n",
3167 tag_name);
3168 if (ret)
3169 return ret;
3170 nr_choices = type->nr_choices;
3171 for (i = 0; i < nr_choices; i++) {
3172 const struct lttng_kernel_event_field *iter_field;
3173
3174 iter_field = type->choices[i];
3175 ret = _lttng_field_statedump(session, iter_field, nesting + 1, NULL);
3176 if (ret)
3177 return ret;
3178 }
3179 ret = print_tabs(session, nesting);
3180 if (ret)
3181 return ret;
3182 ret = lttng_metadata_printf(session,
3183 "}");
3184 return ret;
3185 }
3186
3187 /*
3188 * Must be called with sessions_mutex held.
3189 */
3190 static
3191 int _lttng_variant_field_statedump(struct lttng_kernel_session *session,
3192 const struct lttng_kernel_event_field *field,
3193 size_t nesting,
3194 const char *prev_field_name)
3195 {
3196 int ret;
3197
3198 ret = _lttng_variant_type_statedump(session,
3199 lttng_kernel_get_type_variant(field->type), nesting,
3200 prev_field_name);
3201 if (ret)
3202 return ret;
3203 return lttng_field_name_statedump(session, field, nesting);
3204 }
3205
3206 /*
3207 * Must be called with sessions_mutex held.
3208 */
3209 static
3210 int _lttng_array_field_statedump(struct lttng_kernel_session *session,
3211 const struct lttng_kernel_event_field *field,
3212 size_t nesting)
3213 {
3214 int ret;
3215 const struct lttng_kernel_type_array *array_type;
3216 const struct lttng_kernel_type_common *elem_type;
3217
3218 array_type = lttng_kernel_get_type_array(field->type);
3219 WARN_ON_ONCE(!array_type);
3220
3221 if (array_type->alignment) {
3222 ret = print_tabs(session, nesting);
3223 if (ret)
3224 return ret;
3225 ret = lttng_metadata_printf(session,
3226 "struct { } align(%u) _%s_padding;\n",
3227 array_type->alignment * CHAR_BIT,
3228 field->name);
3229 if (ret)
3230 return ret;
3231 }
3232 /*
3233 * Nested compound types: Only array of structures and variants are
3234 * currently supported.
3235 */
3236 elem_type = array_type->elem_type;
3237 switch (elem_type->type) {
3238 case lttng_kernel_type_integer:
3239 case lttng_kernel_type_struct:
3240 case lttng_kernel_type_variant:
3241 ret = _lttng_type_statedump(session, elem_type,
3242 array_type->encoding, nesting);
3243 if (ret)
3244 return ret;
3245 break;
3246
3247 default:
3248 return -EINVAL;
3249 }
3250 ret = lttng_metadata_printf(session,
3251 " _%s[%u];\n",
3252 field->name,
3253 array_type->length);
3254 return ret;
3255 }
3256
3257 /*
3258 * Must be called with sessions_mutex held.
3259 */
3260 static
3261 int _lttng_sequence_field_statedump(struct lttng_kernel_session *session,
3262 const struct lttng_kernel_event_field *field,
3263 size_t nesting,
3264 const char *prev_field_name)
3265 {
3266 int ret;
3267 const char *length_name;
3268 const struct lttng_kernel_type_sequence *sequence_type;
3269 const struct lttng_kernel_type_common *elem_type;
3270
3271 sequence_type = lttng_kernel_get_type_sequence(field->type);
3272 WARN_ON_ONCE(!sequence_type);
3273
3274 length_name = sequence_type->length_name;
3275 if (!length_name)
3276 length_name = prev_field_name;
3277 if (!length_name)
3278 return -EINVAL;
3279
3280 if (sequence_type->alignment) {
3281 ret = print_tabs(session, nesting);
3282 if (ret)
3283 return ret;
3284 ret = lttng_metadata_printf(session,
3285 "struct { } align(%u) _%s_padding;\n",
3286 sequence_type->alignment * CHAR_BIT,
3287 field->name);
3288 if (ret)
3289 return ret;
3290 }
3291
3292 /*
3293 * Nested compound types: Only array of structures and variants are
3294 * currently supported.
3295 */
3296 elem_type = sequence_type->elem_type;
3297 switch (elem_type->type) {
3298 case lttng_kernel_type_integer:
3299 case lttng_kernel_type_struct:
3300 case lttng_kernel_type_variant:
3301 ret = _lttng_type_statedump(session, elem_type,
3302 sequence_type->encoding, nesting);
3303 if (ret)
3304 return ret;
3305 break;
3306
3307 default:
3308 return -EINVAL;
3309 }
3310 ret = lttng_metadata_printf(session,
3311 " _%s[ _%s ];\n",
3312 field->name,
3313 length_name);
3314 return ret;
3315 }
3316
3317 /*
3318 * Must be called with sessions_mutex held.
3319 */
3320 static
3321 int _lttng_enum_type_statedump(struct lttng_kernel_session *session,
3322 const struct lttng_kernel_type_enum *type,
3323 size_t nesting)
3324 {
3325 const struct lttng_kernel_enum_desc *enum_desc;
3326 const struct lttng_kernel_type_common *container_type;
3327 int ret;
3328 unsigned int i, nr_entries;
3329
3330 container_type = type->container_type;
3331 if (container_type->type != lttng_kernel_type_integer) {
3332 ret = -EINVAL;
3333 goto end;
3334 }
3335 enum_desc = type->desc;
3336 nr_entries = enum_desc->nr_entries;
3337
3338 ret = print_tabs(session, nesting);
3339 if (ret)
3340 goto end;
3341 ret = lttng_metadata_printf(session, "enum : ");
3342 if (ret)
3343 goto end;
3344 ret = _lttng_integer_type_statedump(session, lttng_kernel_get_type_integer(container_type),
3345 lttng_kernel_string_encoding_none, 0);
3346 if (ret)
3347 goto end;
3348 ret = lttng_metadata_printf(session, " {\n");
3349 if (ret)
3350 goto end;
3351 /* Dump all entries */
3352 for (i = 0; i < nr_entries; i++) {
3353 const struct lttng_kernel_enum_entry *entry = enum_desc->entries[i];
3354 int j, len;
3355
3356 ret = print_tabs(session, nesting + 1);
3357 if (ret)
3358 goto end;
3359 ret = lttng_metadata_printf(session,
3360 "\"");
3361 if (ret)
3362 goto end;
3363 len = strlen(entry->string);
3364 /* Escape the character '"' */
3365 for (j = 0; j < len; j++) {
3366 char c = entry->string[j];
3367
3368 switch (c) {
3369 case '"':
3370 ret = lttng_metadata_printf(session,
3371 "\\\"");
3372 break;
3373 case '\\':
3374 ret = lttng_metadata_printf(session,
3375 "\\\\");
3376 break;
3377 default:
3378 ret = lttng_metadata_printf(session,
3379 "%c", c);
3380 break;
3381 }
3382 if (ret)
3383 goto end;
3384 }
3385 ret = lttng_metadata_printf(session, "\"");
3386 if (ret)
3387 goto end;
3388
3389 if (entry->options.is_auto) {
3390 ret = lttng_metadata_printf(session, ",\n");
3391 if (ret)
3392 goto end;
3393 } else {
3394 ret = lttng_metadata_printf(session,
3395 " = ");
3396 if (ret)
3397 goto end;
3398 if (entry->start.signedness)
3399 ret = lttng_metadata_printf(session,
3400 "%lld", (long long) entry->start.value);
3401 else
3402 ret = lttng_metadata_printf(session,
3403 "%llu", entry->start.value);
3404 if (ret)
3405 goto end;
3406 if (entry->start.signedness == entry->end.signedness &&
3407 entry->start.value
3408 == entry->end.value) {
3409 ret = lttng_metadata_printf(session,
3410 ",\n");
3411 } else {
3412 if (entry->end.signedness) {
3413 ret = lttng_metadata_printf(session,
3414 " ... %lld,\n",
3415 (long long) entry->end.value);
3416 } else {
3417 ret = lttng_metadata_printf(session,
3418 " ... %llu,\n",
3419 entry->end.value);
3420 }
3421 }
3422 if (ret)
3423 goto end;
3424 }
3425 }
3426 ret = print_tabs(session, nesting);
3427 if (ret)
3428 goto end;
3429 ret = lttng_metadata_printf(session, "}");
3430 end:
3431 return ret;
3432 }
3433
3434 /*
3435 * Must be called with sessions_mutex held.
3436 */
3437 static
3438 int _lttng_enum_field_statedump(struct lttng_kernel_session *session,
3439 const struct lttng_kernel_event_field *field,
3440 size_t nesting)
3441 {
3442 int ret;
3443 const struct lttng_kernel_type_enum *enum_type;
3444
3445 enum_type = lttng_kernel_get_type_enum(field->type);
3446 WARN_ON_ONCE(!enum_type);
3447 ret = _lttng_enum_type_statedump(session, enum_type, nesting);
3448 if (ret)
3449 return ret;
3450 return lttng_field_name_statedump(session, field, nesting);
3451 }
3452
3453 static
3454 int _lttng_integer_field_statedump(struct lttng_kernel_session *session,
3455 const struct lttng_kernel_event_field *field,
3456 size_t nesting)
3457 {
3458 int ret;
3459
3460 ret = _lttng_integer_type_statedump(session, lttng_kernel_get_type_integer(field->type),
3461 lttng_kernel_string_encoding_none, nesting);
3462 if (ret)
3463 return ret;
3464 return lttng_field_name_statedump(session, field, nesting);
3465 }
3466
3467 static
3468 int _lttng_string_type_statedump(struct lttng_kernel_session *session,
3469 const struct lttng_kernel_type_string *type,
3470 size_t nesting)
3471 {
3472 int ret;
3473
3474 /* Default encoding is UTF8 */
3475 ret = print_tabs(session, nesting);
3476 if (ret)
3477 return ret;
3478 ret = lttng_metadata_printf(session,
3479 "string%s",
3480 type->encoding == lttng_kernel_string_encoding_ASCII ?
3481 " { encoding = ASCII; }" : "");
3482 return ret;
3483 }
3484
3485 static
3486 int _lttng_string_field_statedump(struct lttng_kernel_session *session,
3487 const struct lttng_kernel_event_field *field,
3488 size_t nesting)
3489 {
3490 const struct lttng_kernel_type_string *string_type;
3491 int ret;
3492
3493 string_type = lttng_kernel_get_type_string(field->type);
3494 WARN_ON_ONCE(!string_type);
3495 ret = _lttng_string_type_statedump(session, string_type, nesting);
3496 if (ret)
3497 return ret;
3498 return lttng_field_name_statedump(session, field, nesting);
3499 }
3500
3501 /*
3502 * Must be called with sessions_mutex held.
3503 */
3504 static
3505 int _lttng_type_statedump(struct lttng_kernel_session *session,
3506 const struct lttng_kernel_type_common *type,
3507 enum lttng_kernel_string_encoding parent_encoding,
3508 size_t nesting)
3509 {
3510 int ret = 0;
3511
3512 switch (type->type) {
3513 case lttng_kernel_type_integer:
3514 ret = _lttng_integer_type_statedump(session,
3515 lttng_kernel_get_type_integer(type),
3516 parent_encoding, nesting);
3517 break;
3518 case lttng_kernel_type_enum:
3519 ret = _lttng_enum_type_statedump(session,
3520 lttng_kernel_get_type_enum(type),
3521 nesting);
3522 break;
3523 case lttng_kernel_type_string:
3524 ret = _lttng_string_type_statedump(session,
3525 lttng_kernel_get_type_string(type),
3526 nesting);
3527 break;
3528 case lttng_kernel_type_struct:
3529 ret = _lttng_struct_type_statedump(session,
3530 lttng_kernel_get_type_struct(type),
3531 nesting);
3532 break;
3533 case lttng_kernel_type_variant:
3534 ret = _lttng_variant_type_statedump(session,
3535 lttng_kernel_get_type_variant(type),
3536 nesting, NULL);
3537 break;
3538
3539 /* Nested arrays and sequences are not supported yet. */
3540 case lttng_kernel_type_array:
3541 case lttng_kernel_type_sequence:
3542 default:
3543 WARN_ON_ONCE(1);
3544 return -EINVAL;
3545 }
3546 return ret;
3547 }
3548
3549 /*
3550 * Must be called with sessions_mutex held.
3551 */
3552 static
3553 int _lttng_field_statedump(struct lttng_kernel_session *session,
3554 const struct lttng_kernel_event_field *field,
3555 size_t nesting,
3556 const char **prev_field_name_p)
3557 {
3558 const char *prev_field_name = NULL;
3559 int ret = 0;
3560
3561 if (prev_field_name_p)
3562 prev_field_name = *prev_field_name_p;
3563 switch (field->type->type) {
3564 case lttng_kernel_type_integer:
3565 ret = _lttng_integer_field_statedump(session, field, nesting);
3566 break;
3567 case lttng_kernel_type_enum:
3568 ret = _lttng_enum_field_statedump(session, field, nesting);
3569 break;
3570 case lttng_kernel_type_string:
3571 ret = _lttng_string_field_statedump(session, field, nesting);
3572 break;
3573 case lttng_kernel_type_struct:
3574 ret = _lttng_struct_field_statedump(session, field, nesting);
3575 break;
3576 case lttng_kernel_type_array:
3577 ret = _lttng_array_field_statedump(session, field, nesting);
3578 break;
3579 case lttng_kernel_type_sequence:
3580 ret = _lttng_sequence_field_statedump(session, field, nesting, prev_field_name);
3581 break;
3582 case lttng_kernel_type_variant:
3583 ret = _lttng_variant_field_statedump(session, field, nesting, prev_field_name);
3584 break;
3585
3586 default:
3587 WARN_ON_ONCE(1);
3588 return -EINVAL;
3589 }
3590 if (prev_field_name_p)
3591 *prev_field_name_p = field->name;
3592 return ret;
3593 }
3594
3595 static
3596 int _lttng_context_metadata_statedump(struct lttng_kernel_session *session,
3597 struct lttng_kernel_ctx *ctx)
3598 {
3599 const char *prev_field_name = NULL;
3600 int ret = 0;
3601 int i;
3602
3603 if (!ctx)
3604 return 0;
3605 for (i = 0; i < ctx->nr_fields; i++) {
3606 const struct lttng_kernel_ctx_field *field = &ctx->fields[i];
3607
3608 ret = _lttng_field_statedump(session, field->event_field, 2, &prev_field_name);
3609 if (ret)
3610 return ret;
3611 }
3612 return ret;
3613 }
3614
3615 static
3616 int _lttng_fields_metadata_statedump(struct lttng_kernel_session *session,
3617 struct lttng_kernel_event_recorder *event_recorder)
3618 {
3619 const char *prev_field_name = NULL;
3620 const struct lttng_kernel_event_desc *desc = event_recorder->priv->parent.desc;
3621 int ret = 0;
3622 int i;
3623
3624 for (i = 0; i < desc->tp_class->nr_fields; i++) {
3625 const struct lttng_kernel_event_field *field = desc->tp_class->fields[i];
3626
3627 ret = _lttng_field_statedump(session, field, 2, &prev_field_name);
3628 if (ret)
3629 return ret;
3630 }
3631 return ret;
3632 }
3633
3634 /*
3635 * Must be called with sessions_mutex held.
3636 * The entire event metadata is printed as a single atomic metadata
3637 * transaction.
3638 */
3639 static
3640 int _lttng_event_metadata_statedump(struct lttng_kernel_session *session,
3641 struct lttng_kernel_channel_buffer *chan,
3642 struct lttng_kernel_event_recorder *event_recorder)
3643 {
3644 int ret = 0;
3645
3646 if (event_recorder->priv->metadata_dumped || !LTTNG_READ_ONCE(session->active))
3647 return 0;
3648 if (chan->priv->channel_type == METADATA_CHANNEL)
3649 return 0;
3650
3651 lttng_metadata_begin(session);
3652
3653 ret = lttng_metadata_printf(session,
3654 "event {\n"
3655 " name = \"%s\";\n"
3656 " id = %u;\n"
3657 " stream_id = %u;\n",
3658 event_recorder->priv->parent.desc->event_name,
3659 event_recorder->priv->id,
3660 event_recorder->chan->priv->id);
3661 if (ret)
3662 goto end;
3663
3664 ret = lttng_metadata_printf(session,
3665 " fields := struct {\n"
3666 );
3667 if (ret)
3668 goto end;
3669
3670 ret = _lttng_fields_metadata_statedump(session, event_recorder);
3671 if (ret)
3672 goto end;
3673
3674 /*
3675 * LTTng space reservation can only reserve multiples of the
3676 * byte size.
3677 */
3678 ret = lttng_metadata_printf(session,
3679 " };\n"
3680 "};\n\n");
3681 if (ret)
3682 goto end;
3683
3684 event_recorder->priv->metadata_dumped = 1;
3685 end:
3686 lttng_metadata_end(session);
3687 return ret;
3688
3689 }
3690
3691 /*
3692 * Must be called with sessions_mutex held.
3693 * The entire channel metadata is printed as a single atomic metadata
3694 * transaction.
3695 */
3696 static
3697 int _lttng_channel_metadata_statedump(struct lttng_kernel_session *session,
3698 struct lttng_kernel_channel_buffer *chan)
3699 {
3700 int ret = 0;
3701
3702 if (chan->priv->metadata_dumped || !LTTNG_READ_ONCE(session->active))
3703 return 0;
3704
3705 if (chan->priv->channel_type == METADATA_CHANNEL)
3706 return 0;
3707
3708 lttng_metadata_begin(session);
3709
3710 WARN_ON_ONCE(!chan->priv->header_type);
3711 ret = lttng_metadata_printf(session,
3712 "stream {\n"
3713 " id = %u;\n"
3714 " event.header := %s;\n"
3715 " packet.context := struct packet_context;\n",
3716 chan->priv->id,
3717 chan->priv->header_type == 1 ? "struct event_header_compact" :
3718 "struct event_header_large");
3719 if (ret)
3720 goto end;
3721
3722 if (chan->priv->ctx) {
3723 ret = lttng_metadata_printf(session,
3724 " event.context := struct {\n");
3725 if (ret)
3726 goto end;
3727 }
3728 ret = _lttng_context_metadata_statedump(session, chan->priv->ctx);
3729 if (ret)
3730 goto end;
3731 if (chan->priv->ctx) {
3732 ret = lttng_metadata_printf(session,
3733 " };\n");
3734 if (ret)
3735 goto end;
3736 }
3737
3738 ret = lttng_metadata_printf(session,
3739 "};\n\n");
3740
3741 chan->priv->metadata_dumped = 1;
3742 end:
3743 lttng_metadata_end(session);
3744 return ret;
3745 }
3746
3747 /*
3748 * Must be called with sessions_mutex held.
3749 */
3750 static
3751 int _lttng_stream_packet_context_declare(struct lttng_kernel_session *session)
3752 {
3753 return lttng_metadata_printf(session,
3754 "struct packet_context {\n"
3755 " uint64_clock_monotonic_t timestamp_begin;\n"
3756 " uint64_clock_monotonic_t timestamp_end;\n"
3757 " uint64_t content_size;\n"
3758 " uint64_t packet_size;\n"
3759 " uint64_t packet_seq_num;\n"
3760 " unsigned long events_discarded;\n"
3761 " uint32_t cpu_id;\n"
3762 "};\n\n"
3763 );
3764 }
3765
3766 /*
3767 * Compact header:
3768 * id: range: 0 - 30.
3769 * id 31 is reserved to indicate an extended header.
3770 *
3771 * Large header:
3772 * id: range: 0 - 65534.
3773 * id 65535 is reserved to indicate an extended header.
3774 *
3775 * Must be called with sessions_mutex held.
3776 */
3777 static
3778 int _lttng_event_header_declare(struct lttng_kernel_session *session)
3779 {
3780 return lttng_metadata_printf(session,
3781 "struct event_header_compact {\n"
3782 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
3783 " variant <id> {\n"
3784 " struct {\n"
3785 " uint27_clock_monotonic_t timestamp;\n"
3786 " } compact;\n"
3787 " struct {\n"
3788 " uint32_t id;\n"
3789 " uint64_clock_monotonic_t timestamp;\n"
3790 " } extended;\n"
3791 " } v;\n"
3792 "} align(%u);\n"
3793 "\n"
3794 "struct event_header_large {\n"
3795 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
3796 " variant <id> {\n"
3797 " struct {\n"
3798 " uint32_clock_monotonic_t timestamp;\n"
3799 " } compact;\n"
3800 " struct {\n"
3801 " uint32_t id;\n"
3802 " uint64_clock_monotonic_t timestamp;\n"
3803 " } extended;\n"
3804 " } v;\n"
3805 "} align(%u);\n\n",
3806 lttng_alignof(uint32_t) * CHAR_BIT,
3807 lttng_alignof(uint16_t) * CHAR_BIT
3808 );
3809 }
3810
3811 /*
3812 * Approximation of NTP time of day to clock monotonic correlation,
3813 * taken at start of trace.
3814 * Yes, this is only an approximation. Yes, we can (and will) do better
3815 * in future versions.
3816 * This function may return a negative offset. It may happen if the
3817 * system sets the REALTIME clock to 0 after boot.
3818 *
3819 * Use 64bit timespec on kernels that have it, this makes 32bit arch
3820 * y2038 compliant.
3821 */
3822 static
3823 int64_t measure_clock_offset(void)
3824 {
3825 uint64_t monotonic_avg, monotonic[2], realtime;
3826 uint64_t tcf = trace_clock_freq();
3827 int64_t offset;
3828 unsigned long flags;
3829 #ifdef LTTNG_KERNEL_HAS_TIMESPEC64
3830 struct timespec64 rts = { 0, 0 };
3831 #else
3832 struct timespec rts = { 0, 0 };
3833 #endif
3834
3835 /* Disable interrupts to increase correlation precision. */
3836 local_irq_save(flags);
3837 monotonic[0] = trace_clock_read64();
3838 #ifdef LTTNG_KERNEL_HAS_TIMESPEC64
3839 ktime_get_real_ts64(&rts);
3840 #else
3841 getnstimeofday(&rts);
3842 #endif
3843 monotonic[1] = trace_clock_read64();
3844 local_irq_restore(flags);
3845
3846 monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
3847 realtime = (uint64_t) rts.tv_sec * tcf;
3848 if (tcf == NSEC_PER_SEC) {
3849 realtime += rts.tv_nsec;
3850 } else {
3851 uint64_t n = rts.tv_nsec * tcf;
3852
3853 do_div(n, NSEC_PER_SEC);
3854 realtime += n;
3855 }
3856 offset = (int64_t) realtime - monotonic_avg;
3857 return offset;
3858 }
3859
3860 static
3861 int print_escaped_ctf_string(struct lttng_kernel_session *session, const char *string)
3862 {
3863 int ret = 0;
3864 size_t i;
3865 char cur;
3866
3867 i = 0;
3868 cur = string[i];
3869 while (cur != '\0') {
3870 switch (cur) {
3871 case '\n':
3872 ret = lttng_metadata_printf(session, "%s", "\\n");
3873 break;
3874 case '\\':
3875 case '"':
3876 ret = lttng_metadata_printf(session, "%c", '\\');
3877 if (ret)
3878 goto error;
3879 /* We still print the current char */
3880 /* Fallthrough */
3881 default:
3882 ret = lttng_metadata_printf(session, "%c", cur);
3883 break;
3884 }
3885
3886 if (ret)
3887 goto error;
3888
3889 cur = string[++i];
3890 }
3891 error:
3892 return ret;
3893 }
3894
3895 static
3896 int print_metadata_escaped_field(struct lttng_kernel_session *session, const char *field,
3897 const char *field_value)
3898 {
3899 int ret;
3900
3901 ret = lttng_metadata_printf(session, " %s = \"", field);
3902 if (ret)
3903 goto error;
3904
3905 ret = print_escaped_ctf_string(session, field_value);
3906 if (ret)
3907 goto error;
3908
3909 ret = lttng_metadata_printf(session, "\";\n");
3910
3911 error:
3912 return ret;
3913 }
3914
3915 /*
3916 * Output metadata into this session's metadata buffers.
3917 * Must be called with sessions_mutex held.
3918 */
3919 static
3920 int _lttng_session_metadata_statedump(struct lttng_kernel_session *session)
3921 {
3922 unsigned char *uuid_c = session->priv->uuid.b;
3923 unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN];
3924 const char *product_uuid;
3925 struct lttng_kernel_channel_buffer_private *chan_priv;
3926 struct lttng_kernel_event_recorder_private *event_recorder_priv;
3927 int ret = 0;
3928
3929 if (!LTTNG_READ_ONCE(session->active))
3930 return 0;
3931
3932 lttng_metadata_begin(session);
3933
3934 if (session->priv->metadata_dumped)
3935 goto skip_session;
3936
3937 snprintf(uuid_s, sizeof(uuid_s),
3938 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
3939 uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3],
3940 uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7],
3941 uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11],
3942 uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]);
3943
3944 ret = lttng_metadata_printf(session,
3945 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
3946 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
3947 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
3948 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
3949 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
3950 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
3951 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
3952 "\n"
3953 "trace {\n"
3954 " major = %u;\n"
3955 " minor = %u;\n"
3956 " uuid = \"%s\";\n"
3957 " byte_order = %s;\n"
3958 " packet.header := struct {\n"
3959 " uint32_t magic;\n"
3960 " uint8_t uuid[16];\n"
3961 " uint32_t stream_id;\n"
3962 " uint64_t stream_instance_id;\n"
3963 " };\n"
3964 "};\n\n",
3965 lttng_alignof(uint8_t) * CHAR_BIT,
3966 lttng_alignof(uint16_t) * CHAR_BIT,
3967 lttng_alignof(uint32_t) * CHAR_BIT,
3968 lttng_alignof(uint64_t) * CHAR_BIT,
3969 sizeof(unsigned long) * CHAR_BIT,
3970 lttng_alignof(unsigned long) * CHAR_BIT,
3971 CTF_SPEC_MAJOR,
3972 CTF_SPEC_MINOR,
3973 uuid_s,
3974 #if __BYTE_ORDER == __BIG_ENDIAN
3975 "be"
3976 #else
3977 "le"
3978 #endif
3979 );
3980 if (ret)
3981 goto end;
3982
3983 ret = lttng_metadata_printf(session,
3984 "env {\n"
3985 " hostname = \"%s\";\n"
3986 " domain = \"kernel\";\n"
3987 " sysname = \"%s\";\n"
3988 " kernel_release = \"%s\";\n"
3989 " kernel_version = \"%s\";\n"
3990 " tracer_name = \"lttng-modules\";\n"
3991 " tracer_major = %d;\n"
3992 " tracer_minor = %d;\n"
3993 " tracer_patchlevel = %d;\n"
3994 " trace_buffering_scheme = \"global\";\n",
3995 current->nsproxy->uts_ns->name.nodename,
3996 utsname()->sysname,
3997 utsname()->release,
3998 utsname()->version,
3999 LTTNG_MODULES_MAJOR_VERSION,
4000 LTTNG_MODULES_MINOR_VERSION,
4001 LTTNG_MODULES_PATCHLEVEL_VERSION
4002 );
4003 if (ret)
4004 goto end;
4005
4006 ret = print_metadata_escaped_field(session, "trace_name", session->priv->name);
4007 if (ret)
4008 goto end;
4009 ret = print_metadata_escaped_field(session, "trace_creation_datetime",
4010 session->priv->creation_time);
4011 if (ret)
4012 goto end;
4013
4014 /* Add the product UUID to the 'env' section */
4015 product_uuid = dmi_get_system_info(DMI_PRODUCT_UUID);
4016 if (product_uuid) {
4017 ret = lttng_metadata_printf(session,
4018 " product_uuid = \"%s\";\n",
4019 product_uuid
4020 );
4021 if (ret)
4022 goto end;
4023 }
4024
4025 /* Close the 'env' section */
4026 ret = lttng_metadata_printf(session, "};\n\n");
4027 if (ret)
4028 goto end;
4029
4030 ret = lttng_metadata_printf(session,
4031 "clock {\n"
4032 " name = \"%s\";\n",
4033 trace_clock_name()
4034 );
4035 if (ret)
4036 goto end;
4037
4038 if (!trace_clock_uuid(clock_uuid_s)) {
4039 ret = lttng_metadata_printf(session,
4040 " uuid = \"%s\";\n",
4041 clock_uuid_s
4042 );
4043 if (ret)
4044 goto end;
4045 }
4046
4047 ret = lttng_metadata_printf(session,
4048 " description = \"%s\";\n"
4049 " freq = %llu; /* Frequency, in Hz */\n"
4050 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
4051 " offset = %lld;\n"
4052 "};\n\n",
4053 trace_clock_description(),
4054 (unsigned long long) trace_clock_freq(),
4055 (long long) measure_clock_offset()
4056 );
4057 if (ret)
4058 goto end;
4059
4060 ret = lttng_metadata_printf(session,
4061 "typealias integer {\n"
4062 " size = 27; align = 1; signed = false;\n"
4063 " map = clock.%s.value;\n"
4064 "} := uint27_clock_monotonic_t;\n"
4065 "\n"
4066 "typealias integer {\n"
4067 " size = 32; align = %u; signed = false;\n"
4068 " map = clock.%s.value;\n"
4069 "} := uint32_clock_monotonic_t;\n"
4070 "\n"
4071 "typealias integer {\n"
4072 " size = 64; align = %u; signed = false;\n"
4073 " map = clock.%s.value;\n"
4074 "} := uint64_clock_monotonic_t;\n\n",
4075 trace_clock_name(),
4076 lttng_alignof(uint32_t) * CHAR_BIT,
4077 trace_clock_name(),
4078 lttng_alignof(uint64_t) * CHAR_BIT,
4079 trace_clock_name()
4080 );
4081 if (ret)
4082 goto end;
4083
4084 ret = _lttng_stream_packet_context_declare(session);
4085 if (ret)
4086 goto end;
4087
4088 ret = _lttng_event_header_declare(session);
4089 if (ret)
4090 goto end;
4091
4092 skip_session:
4093 list_for_each_entry(chan_priv, &session->priv->chan, node) {
4094 ret = _lttng_channel_metadata_statedump(session, chan_priv->pub);
4095 if (ret)
4096 goto end;
4097 }
4098
4099 list_for_each_entry(event_recorder_priv, &session->priv->events, node) {
4100 ret = _lttng_event_metadata_statedump(session, event_recorder_priv->pub->chan,
4101 event_recorder_priv->pub);
4102 if (ret)
4103 goto end;
4104 }
4105 session->priv->metadata_dumped = 1;
4106 end:
4107 lttng_metadata_end(session);
4108 return ret;
4109 }
4110
4111 /**
4112 * lttng_transport_register - LTT transport registration
4113 * @transport: transport structure
4114 *
4115 * Registers a transport which can be used as output to extract the data out of
4116 * LTTng. The module calling this registration function must ensure that no
4117 * trap-inducing code will be executed by the transport functions. E.g.
4118 * vmalloc_sync_mappings() must be called between a vmalloc and the moment the memory
4119 * is made visible to the transport function. This registration acts as a
4120 * vmalloc_sync_mappings. Therefore, only if the module allocates virtual memory
4121 * after its registration must it synchronize the TLBs.
4122 */
4123 void lttng_transport_register(struct lttng_transport *transport)
4124 {
4125 /*
4126 * Make sure no page fault can be triggered by the module about to be
4127 * registered. We deal with this here so we don't have to call
4128 * vmalloc_sync_mappings() in each module's init.
4129 */
4130 wrapper_vmalloc_sync_mappings();
4131
4132 mutex_lock(&sessions_mutex);
4133 list_add_tail(&transport->node, &lttng_transport_list);
4134 mutex_unlock(&sessions_mutex);
4135 }
4136 EXPORT_SYMBOL_GPL(lttng_transport_register);
4137
4138 /**
4139 * lttng_transport_unregister - LTT transport unregistration
4140 * @transport: transport structure
4141 */
4142 void lttng_transport_unregister(struct lttng_transport *transport)
4143 {
4144 mutex_lock(&sessions_mutex);
4145 list_del(&transport->node);
4146 mutex_unlock(&sessions_mutex);
4147 }
4148 EXPORT_SYMBOL_GPL(lttng_transport_unregister);
4149
4150 void lttng_counter_transport_register(struct lttng_counter_transport *transport)
4151 {
4152 /*
4153 * Make sure no page fault can be triggered by the module about to be
4154 * registered. We deal with this here so we don't have to call
4155 * vmalloc_sync_mappings() in each module's init.
4156 */
4157 wrapper_vmalloc_sync_mappings();
4158
4159 mutex_lock(&sessions_mutex);
4160 list_add_tail(&transport->node, &lttng_counter_transport_list);
4161 mutex_unlock(&sessions_mutex);
4162 }
4163 EXPORT_SYMBOL_GPL(lttng_counter_transport_register);
4164
4165 void lttng_counter_transport_unregister(struct lttng_counter_transport *transport)
4166 {
4167 mutex_lock(&sessions_mutex);
4168 list_del(&transport->node);
4169 mutex_unlock(&sessions_mutex);
4170 }
4171 EXPORT_SYMBOL_GPL(lttng_counter_transport_unregister);
4172
4173 #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0))
4174
4175 enum cpuhp_state lttng_hp_prepare;
4176 enum cpuhp_state lttng_hp_online;
4177
4178 static int lttng_hotplug_prepare(unsigned int cpu, struct hlist_node *node)
4179 {
4180 struct lttng_cpuhp_node *lttng_node;
4181
4182 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4183 switch (lttng_node->component) {
4184 case LTTNG_RING_BUFFER_FRONTEND:
4185 return 0;
4186 case LTTNG_RING_BUFFER_BACKEND:
4187 return lttng_cpuhp_rb_backend_prepare(cpu, lttng_node);
4188 case LTTNG_RING_BUFFER_ITER:
4189 return 0;
4190 case LTTNG_CONTEXT_PERF_COUNTERS:
4191 return 0;
4192 default:
4193 return -EINVAL;
4194 }
4195 }
4196
4197 static int lttng_hotplug_dead(unsigned int cpu, struct hlist_node *node)
4198 {
4199 struct lttng_cpuhp_node *lttng_node;
4200
4201 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4202 switch (lttng_node->component) {
4203 case LTTNG_RING_BUFFER_FRONTEND:
4204 return lttng_cpuhp_rb_frontend_dead(cpu, lttng_node);
4205 case LTTNG_RING_BUFFER_BACKEND:
4206 return 0;
4207 case LTTNG_RING_BUFFER_ITER:
4208 return 0;
4209 case LTTNG_CONTEXT_PERF_COUNTERS:
4210 return lttng_cpuhp_perf_counter_dead(cpu, lttng_node);
4211 default:
4212 return -EINVAL;
4213 }
4214 }
4215
4216 static int lttng_hotplug_online(unsigned int cpu, struct hlist_node *node)
4217 {
4218 struct lttng_cpuhp_node *lttng_node;
4219
4220 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4221 switch (lttng_node->component) {
4222 case LTTNG_RING_BUFFER_FRONTEND:
4223 return lttng_cpuhp_rb_frontend_online(cpu, lttng_node);
4224 case LTTNG_RING_BUFFER_BACKEND:
4225 return 0;
4226 case LTTNG_RING_BUFFER_ITER:
4227 return lttng_cpuhp_rb_iter_online(cpu, lttng_node);
4228 case LTTNG_CONTEXT_PERF_COUNTERS:
4229 return lttng_cpuhp_perf_counter_online(cpu, lttng_node);
4230 default:
4231 return -EINVAL;
4232 }
4233 }
4234
4235 static int lttng_hotplug_offline(unsigned int cpu, struct hlist_node *node)
4236 {
4237 struct lttng_cpuhp_node *lttng_node;
4238
4239 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
4240 switch (lttng_node->component) {
4241 case LTTNG_RING_BUFFER_FRONTEND:
4242 return lttng_cpuhp_rb_frontend_offline(cpu, lttng_node);
4243 case LTTNG_RING_BUFFER_BACKEND:
4244 return 0;
4245 case LTTNG_RING_BUFFER_ITER:
4246 return 0;
4247 case LTTNG_CONTEXT_PERF_COUNTERS:
4248 return 0;
4249 default:
4250 return -EINVAL;
4251 }
4252 }
4253
4254 static int __init lttng_init_cpu_hotplug(void)
4255 {
4256 int ret;
4257
4258 ret = cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN, "lttng:prepare",
4259 lttng_hotplug_prepare,
4260 lttng_hotplug_dead);
4261 if (ret < 0) {
4262 return ret;
4263 }
4264 lttng_hp_prepare = ret;
4265 lttng_rb_set_hp_prepare(ret);
4266
4267 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "lttng:online",
4268 lttng_hotplug_online,
4269 lttng_hotplug_offline);
4270 if (ret < 0) {
4271 cpuhp_remove_multi_state(lttng_hp_prepare);
4272 lttng_hp_prepare = 0;
4273 return ret;
4274 }
4275 lttng_hp_online = ret;
4276 lttng_rb_set_hp_online(ret);
4277
4278 return 0;
4279 }
4280
4281 static void __exit lttng_exit_cpu_hotplug(void)
4282 {
4283 lttng_rb_set_hp_online(0);
4284 cpuhp_remove_multi_state(lttng_hp_online);
4285 lttng_rb_set_hp_prepare(0);
4286 cpuhp_remove_multi_state(lttng_hp_prepare);
4287 }
4288
4289 #else /* #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
4290 static int lttng_init_cpu_hotplug(void)
4291 {
4292 return 0;
4293 }
4294 static void lttng_exit_cpu_hotplug(void)
4295 {
4296 }
4297 #endif /* #else #if (LTTNG_LINUX_VERSION_CODE >= LTTNG_KERNEL_VERSION(4,10,0)) */
4298
4299 static int __init lttng_events_init(void)
4300 {
4301 int ret;
4302
4303 ret = wrapper_lttng_fixup_sig(THIS_MODULE);
4304 if (ret)
4305 return ret;
4306 ret = wrapper_get_pfnblock_flags_mask_init();
4307 if (ret)
4308 return ret;
4309 ret = wrapper_get_pageblock_flags_mask_init();
4310 if (ret)
4311 return ret;
4312 ret = lttng_probes_init();
4313 if (ret)
4314 return ret;
4315 ret = lttng_context_init();
4316 if (ret)
4317 return ret;
4318 ret = lttng_tracepoint_init();
4319 if (ret)
4320 goto error_tp;
4321 event_recorder_cache = KMEM_CACHE(lttng_kernel_event_recorder, 0);
4322 if (!event_recorder_cache) {
4323 ret = -ENOMEM;
4324 goto error_kmem_event_recorder;
4325 }
4326 event_recorder_private_cache = KMEM_CACHE(lttng_kernel_event_recorder_private, 0);
4327 if (!event_recorder_private_cache) {
4328 ret = -ENOMEM;
4329 goto error_kmem_event_recorder_private;
4330 }
4331 event_notifier_cache = KMEM_CACHE(lttng_kernel_event_notifier, 0);
4332 if (!event_notifier_cache) {
4333 ret = -ENOMEM;
4334 goto error_kmem_event_notifier;
4335 }
4336 event_notifier_private_cache = KMEM_CACHE(lttng_kernel_event_notifier_private, 0);
4337 if (!event_notifier_private_cache) {
4338 ret = -ENOMEM;
4339 goto error_kmem_event_notifier_private;
4340 }
4341 ret = lttng_abi_init();
4342 if (ret)
4343 goto error_abi;
4344 ret = lttng_logger_init();
4345 if (ret)
4346 goto error_logger;
4347 ret = lttng_init_cpu_hotplug();
4348 if (ret)
4349 goto error_hotplug;
4350 printk(KERN_NOTICE "LTTng: Loaded modules v%s.%s.%s%s (%s)%s%s\n",
4351 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4352 __stringify(LTTNG_MODULES_MINOR_VERSION),
4353 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4354 LTTNG_MODULES_EXTRAVERSION,
4355 LTTNG_VERSION_NAME,
4356 #ifdef LTTNG_EXTRA_VERSION_GIT
4357 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4358 #else
4359 "",
4360 #endif
4361 #ifdef LTTNG_EXTRA_VERSION_NAME
4362 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4363 #else
4364 "");
4365 #endif
4366 #ifdef CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM
4367 printk(KERN_NOTICE "LTTng: Experimental bitwise enum enabled.\n");
4368 #endif /* CONFIG_LTTNG_EXPERIMENTAL_BITWISE_ENUM */
4369 return 0;
4370
4371 error_hotplug:
4372 lttng_logger_exit();
4373 error_logger:
4374 lttng_abi_exit();
4375 error_abi:
4376 kmem_cache_destroy(event_notifier_private_cache);
4377 error_kmem_event_notifier_private:
4378 kmem_cache_destroy(event_notifier_cache);
4379 error_kmem_event_notifier:
4380 kmem_cache_destroy(event_recorder_private_cache);
4381 error_kmem_event_recorder_private:
4382 kmem_cache_destroy(event_recorder_cache);
4383 error_kmem_event_recorder:
4384 lttng_tracepoint_exit();
4385 error_tp:
4386 lttng_context_exit();
4387 printk(KERN_NOTICE "LTTng: Failed to load modules v%s.%s.%s%s (%s)%s%s\n",
4388 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4389 __stringify(LTTNG_MODULES_MINOR_VERSION),
4390 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4391 LTTNG_MODULES_EXTRAVERSION,
4392 LTTNG_VERSION_NAME,
4393 #ifdef LTTNG_EXTRA_VERSION_GIT
4394 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4395 #else
4396 "",
4397 #endif
4398 #ifdef LTTNG_EXTRA_VERSION_NAME
4399 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4400 #else
4401 "");
4402 #endif
4403 return ret;
4404 }
4405
4406 module_init(lttng_events_init);
4407
4408 static void __exit lttng_events_exit(void)
4409 {
4410 struct lttng_kernel_session_private *session_priv, *tmpsession_priv;
4411
4412 lttng_exit_cpu_hotplug();
4413 lttng_logger_exit();
4414 lttng_abi_exit();
4415 list_for_each_entry_safe(session_priv, tmpsession_priv, &sessions, list)
4416 lttng_session_destroy(session_priv->pub);
4417 kmem_cache_destroy(event_recorder_cache);
4418 kmem_cache_destroy(event_recorder_private_cache);
4419 kmem_cache_destroy(event_notifier_cache);
4420 kmem_cache_destroy(event_notifier_private_cache);
4421 lttng_tracepoint_exit();
4422 lttng_context_exit();
4423 printk(KERN_NOTICE "LTTng: Unloaded modules v%s.%s.%s%s (%s)%s%s\n",
4424 __stringify(LTTNG_MODULES_MAJOR_VERSION),
4425 __stringify(LTTNG_MODULES_MINOR_VERSION),
4426 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
4427 LTTNG_MODULES_EXTRAVERSION,
4428 LTTNG_VERSION_NAME,
4429 #ifdef LTTNG_EXTRA_VERSION_GIT
4430 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
4431 #else
4432 "",
4433 #endif
4434 #ifdef LTTNG_EXTRA_VERSION_NAME
4435 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
4436 #else
4437 "");
4438 #endif
4439 }
4440
4441 module_exit(lttng_events_exit);
4442
4443 #include <generated/patches.h>
4444 #ifdef LTTNG_EXTRA_VERSION_GIT
4445 MODULE_INFO(extra_version_git, LTTNG_EXTRA_VERSION_GIT);
4446 #endif
4447 #ifdef LTTNG_EXTRA_VERSION_NAME
4448 MODULE_INFO(extra_version_name, LTTNG_EXTRA_VERSION_NAME);
4449 #endif
4450 MODULE_LICENSE("GPL and additional rights");
4451 MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
4452 MODULE_DESCRIPTION("LTTng tracer");
4453 MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
4454 __stringify(LTTNG_MODULES_MINOR_VERSION) "."
4455 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
4456 LTTNG_MODULES_EXTRAVERSION);
LTTng 2.0/0.x modules
This page took 0.158668 seconds and 4 git commands to generate.