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Add token to `struct lttng_kernel_event`
[lttng-modules.git] / src / lttng-events.c
CommitLineData
b7cdc182 1/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
9f36eaed 2 *
a90917c3 3 * lttng-events.c
4e3c1b9b 4 *
4e3c1b9b 5 * Holds LTTng per-session event registry.
17baffe2 6 *
886d51a3 7 * Copyright (C) 2010-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4e3c1b9b
MD		 8 */
9
389d7070
MD		 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
4e3c1b9b 16#include <linux/module.h>
c0e31d2e
MD		 17#include <linux/mutex.h>
18#include <linux/sched.h>
11b5a3c2 19#include <linux/slab.h>
c099397a 20#include <linux/jiffies.h>
99dc9597 21#include <linux/utsname.h>
abc0446a 22#include <linux/err.h>
7e6f9ef6
MD		 23#include <linux/seq_file.h>
24#include <linux/file.h>
25#include <linux/anon_inodes.h>
241ae9a8 26#include <wrapper/file.h>
8c6e7f13 27#include <linux/uaccess.h>
a606b6e8 28#include <linux/vmalloc.h>
c88f762e 29#include <linux/dmi.h>
3c997079 30
a7008254 31#include <wrapper/uuid.h>
263b6c88 32#include <wrapper/vmalloc.h> /* for wrapper_vmalloc_sync_mappings() */
241ae9a8
MD		 33#include <wrapper/random.h>
34#include <wrapper/tracepoint.h>
35#include <wrapper/list.h>
cbc19040 36#include <wrapper/types.h>
2df37e95
MD		 37#include <lttng/kernel-version.h>
38#include <lttng/events.h>
39#include <lttng/tracer.h>
40#include <lttng/abi-old.h>
41#include <lttng/endian.h>
42#include <lttng/string-utils.h>
4a11ef1c 43#include <lttng/utils.h>
24591303
MD		 44#include <ringbuffer/backend.h>
45#include <ringbuffer/frontend.h>
3636085f 46#include <wrapper/time.h>
4e3c1b9b 47
d83004aa
JD		 48#define METADATA_CACHE_DEFAULT_SIZE 4096
49
4e3c1b9b 50static LIST_HEAD(sessions);
a90917c3 51static LIST_HEAD(lttng_transport_list);
d83004aa
JD		 52/*
53 * Protect the sessions and metadata caches.
54 */
4e3c1b9b
MD		 55static DEFINE_MUTEX(sessions_mutex);
56static struct kmem_cache *event_cache;
57
b2bc0bc8
FD		 58static void lttng_session_lazy_sync_event_enablers(struct lttng_session *session);
59static void lttng_session_sync_event_enablers(struct lttng_session *session);
60static void lttng_event_enabler_destroy(struct lttng_event_enabler *event_enabler);
3c997079 61
a90917c3
MD		 62static void _lttng_event_destroy(struct lttng_event *event);
63static void _lttng_channel_destroy(struct lttng_channel *chan);
64static int _lttng_event_unregister(struct lttng_event *event);
c099397a 65static
a90917c3
MD		 66int _lttng_event_metadata_statedump(struct lttng_session *session,
67 struct lttng_channel *chan,
68 struct lttng_event *event);
c099397a 69static
a90917c3 70int _lttng_session_metadata_statedump(struct lttng_session *session);
d83004aa
JD		 71static
72void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream);
f513b2bf 73static
ceabb767
MD		 74int _lttng_type_statedump(struct lttng_session *session,
75 const struct lttng_type *type,
76 size_t nesting);
77static
f513b2bf
MD		 78int _lttng_field_statedump(struct lttng_session *session,
79 const struct lttng_event_field *field,
80 size_t nesting);
c099397a 81
c099397a 82void synchronize_trace(void)
abcca994 83{
92da05ce
MJ		 84#if (LINUX_VERSION_CODE >= KERNEL_VERSION(5,1,0))
85 synchronize_rcu();
86#else
abcca994 87 synchronize_sched();
92da05ce
MJ		 88#endif
89
b8590f40
MD		 90#if (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0))
91#ifdef CONFIG_PREEMPT_RT_FULL
92 synchronize_rcu();
93#endif
94#else /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */
abcca994
MD		 95#ifdef CONFIG_PREEMPT_RT
96 synchronize_rcu();
97#endif
b8590f40 98#endif /* (LINUX_VERSION_CODE >= KERNEL_VERSION(3,4,0)) */
abcca994
MD		 99}
100
3c997079
MD		 101void lttng_lock_sessions(void)
102{
103 mutex_lock(&sessions_mutex);
104}
105
106void lttng_unlock_sessions(void)
107{
108 mutex_unlock(&sessions_mutex);
109}
110
9fe593d2
FD		 111static struct lttng_transport *lttng_transport_find(const char *name)
112{
113 struct lttng_transport *transport;
114
115 list_for_each_entry(transport, &lttng_transport_list, node) {
116 if (!strcmp(transport->name, name))
117 return transport;
118 }
119 return NULL;
120}
121
3c997079
MD		 122/*
123 * Called with sessions lock held.
124 */
125int lttng_session_active(void)
126{
127 struct lttng_session *iter;
128
129 list_for_each_entry(iter, &sessions, list) {
130 if (iter->active)
131 return 1;
132 }
133 return 0;
134}
135
a90917c3 136struct lttng_session *lttng_session_create(void)
4e3c1b9b 137{
a90917c3 138 struct lttng_session *session;
d83004aa 139 struct lttng_metadata_cache *metadata_cache;
3c997079 140 int i;
4e3c1b9b
MD		 141
142 mutex_lock(&sessions_mutex);
48f5e0b5 143 session = lttng_kvzalloc(sizeof(struct lttng_session), GFP_KERNEL);
4e3c1b9b 144 if (!session)
d83004aa 145 goto err;
4e3c1b9b 146 INIT_LIST_HEAD(&session->chan);
f3d01b96 147 INIT_LIST_HEAD(&session->events);
a7008254 148 lttng_guid_gen(&session->uuid);
d83004aa
JD		 149
150 metadata_cache = kzalloc(sizeof(struct lttng_metadata_cache),
151 GFP_KERNEL);
152 if (!metadata_cache)
153 goto err_free_session;
0ca42eb7 154 metadata_cache->data = vzalloc(METADATA_CACHE_DEFAULT_SIZE);
d83004aa
JD		 155 if (!metadata_cache->data)
156 goto err_free_cache;
157 metadata_cache->cache_alloc = METADATA_CACHE_DEFAULT_SIZE;
158 kref_init(&metadata_cache->refcount);
92d9f5e6 159 mutex_init(&metadata_cache->lock);
d83004aa
JD		 160 session->metadata_cache = metadata_cache;
161 INIT_LIST_HEAD(&metadata_cache->metadata_stream);
a36580d5
MD		 162 memcpy(&metadata_cache->uuid, &session->uuid,
163 sizeof(metadata_cache->uuid));
3c997079
MD		 164 INIT_LIST_HEAD(&session->enablers_head);
165 for (i = 0; i < LTTNG_EVENT_HT_SIZE; i++)
166 INIT_HLIST_HEAD(&session->events_ht.table[i]);
4e3c1b9b 167 list_add(&session->list, &sessions);
d1f652f8
MD		 168 session->pid_tracker.session = session;
169 session->pid_tracker.tracker_type = TRACKER_PID;
170 session->vpid_tracker.session = session;
171 session->vpid_tracker.tracker_type = TRACKER_VPID;
172 session->uid_tracker.session = session;
173 session->uid_tracker.tracker_type = TRACKER_UID;
174 session->vuid_tracker.session = session;
175 session->vuid_tracker.tracker_type = TRACKER_VUID;
176 session->gid_tracker.session = session;
177 session->gid_tracker.tracker_type = TRACKER_GID;
178 session->vgid_tracker.session = session;
179 session->vgid_tracker.tracker_type = TRACKER_VGID;
4e3c1b9b
MD		 180 mutex_unlock(&sessions_mutex);
181 return session;
d83004aa
JD		 182
183err_free_cache:
184 kfree(metadata_cache);
185err_free_session:
48f5e0b5 186 lttng_kvfree(session);
d83004aa
JD		 187err:
188 mutex_unlock(&sessions_mutex);
189 return NULL;
190}
191
192void metadata_cache_destroy(struct kref *kref)
193{
194 struct lttng_metadata_cache *cache =
195 container_of(kref, struct lttng_metadata_cache, refcount);
a606b6e8 196 vfree(cache->data);
d83004aa 197 kfree(cache);
4e3c1b9b
MD		 198}
199
a90917c3 200void lttng_session_destroy(struct lttng_session *session)
4e3c1b9b 201{
a90917c3
MD		 202 struct lttng_channel *chan, *tmpchan;
203 struct lttng_event *event, *tmpevent;
d83004aa 204 struct lttng_metadata_stream *metadata_stream;
b2bc0bc8 205 struct lttng_event_enabler *event_enabler, *tmp_event_enabler;
dda6a249 206 int ret;
4e3c1b9b
MD		 207
208 mutex_lock(&sessions_mutex);
a8f2d0c7 209 WRITE_ONCE(session->active, 0);
1ec65de1
MD		 210 list_for_each_entry(chan, &session->chan, list) {
211 ret = lttng_syscalls_unregister(chan);
212 WARN_ON(ret);
213 }
dda6a249 214 list_for_each_entry(event, &session->events, list) {
a90917c3 215 ret = _lttng_event_unregister(event);
dda6a249
MD		 216 WARN_ON(ret);
217 }
abcca994 218 synchronize_trace(); /* Wait for in-flight events to complete */
badfe9f5
MD		 219 list_for_each_entry(chan, &session->chan, list) {
220 ret = lttng_syscalls_destroy(chan);
221 WARN_ON(ret);
222 }
b2bc0bc8 223 list_for_each_entry_safe(event_enabler, tmp_event_enabler,
3c997079 224 &session->enablers_head, node)
b2bc0bc8 225 lttng_event_enabler_destroy(event_enabler);
4e3c1b9b 226 list_for_each_entry_safe(event, tmpevent, &session->events, list)
a90917c3 227 _lttng_event_destroy(event);
d83004aa
JD		 228 list_for_each_entry_safe(chan, tmpchan, &session->chan, list) {
229 BUG_ON(chan->channel_type == METADATA_CHANNEL);
a90917c3 230 _lttng_channel_destroy(chan);
d83004aa 231 }
ab036a63 232 mutex_lock(&session->metadata_cache->lock);
d83004aa
JD		 233 list_for_each_entry(metadata_stream, &session->metadata_cache->metadata_stream, list)
234 _lttng_metadata_channel_hangup(metadata_stream);
ab036a63 235 mutex_unlock(&session->metadata_cache->lock);
d1f652f8
MD		 236 lttng_id_tracker_destroy(&session->pid_tracker, false);
237 lttng_id_tracker_destroy(&session->vpid_tracker, false);
238 lttng_id_tracker_destroy(&session->uid_tracker, false);
239 lttng_id_tracker_destroy(&session->vuid_tracker, false);
240 lttng_id_tracker_destroy(&session->gid_tracker, false);
241 lttng_id_tracker_destroy(&session->vgid_tracker, false);
d83004aa 242 kref_put(&session->metadata_cache->refcount, metadata_cache_destroy);
4e3c1b9b
MD		 243 list_del(&session->list);
244 mutex_unlock(&sessions_mutex);
48f5e0b5 245 lttng_kvfree(session);
4e3c1b9b
MD		 246}
247
601252cf
MD		 248int lttng_session_statedump(struct lttng_session *session)
249{
250 int ret;
251
252 mutex_lock(&sessions_mutex);
253 ret = lttng_statedump_start(session);
254 mutex_unlock(&sessions_mutex);
255 return ret;
256}
257
a90917c3 258int lttng_session_enable(struct lttng_session *session)
c0e31d2e
MD		 259{
260 int ret = 0;
a90917c3 261 struct lttng_channel *chan;
c0e31d2e
MD		 262
263 mutex_lock(&sessions_mutex);
264 if (session->active) {
265 ret = -EBUSY;
266 goto end;
267 }
c099397a 268
3c997079
MD		 269 /* Set transient enabler state to "enabled" */
270 session->tstate = 1;
271
4ef81e4a 272 /* We need to sync enablers with session before activation. */
b2bc0bc8 273 lttng_session_sync_event_enablers(session);
4ef81e4a 274
c099397a
MD		 275 /*
276 * Snapshot the number of events per channel to know the type of header
277 * we need to use.
278 */
279 list_for_each_entry(chan, &session->chan, list) {
280 if (chan->header_type)
281 continue; /* don't change it if session stop/restart */
282 if (chan->free_event_id < 31)
283 chan->header_type = 1; /* compact */
284 else
285 chan->header_type = 2; /* large */
286 }
287
64af2437 288 /* Clear each stream's quiescent state. */
09b93db9
MD		 289 list_for_each_entry(chan, &session->chan, list) {
290 if (chan->channel_type != METADATA_CHANNEL)
291 lib_ring_buffer_clear_quiescent_channel(chan->chan);
292 }
64af2437 293
a8f2d0c7
MJ		 294 WRITE_ONCE(session->active, 1);
295 WRITE_ONCE(session->been_active, 1);
a90917c3 296 ret = _lttng_session_metadata_statedump(session);
c337ddc2 297 if (ret) {
a8f2d0c7 298 WRITE_ONCE(session->active, 0);
c337ddc2
MD		 299 goto end;
300 }
301 ret = lttng_statedump_start(session);
360f38ea 302 if (ret)
a8f2d0c7 303 WRITE_ONCE(session->active, 0);
c0e31d2e
MD		 304end:
305 mutex_unlock(&sessions_mutex);
11b5a3c2 306 return ret;
c0e31d2e
MD		 307}
308
a90917c3 309int lttng_session_disable(struct lttng_session *session)
c0e31d2e
MD		 310{
311 int ret = 0;
64af2437 312 struct lttng_channel *chan;
c0e31d2e
MD		 313
314 mutex_lock(&sessions_mutex);
315 if (!session->active) {
316 ret = -EBUSY;
317 goto end;
318 }
a8f2d0c7 319 WRITE_ONCE(session->active, 0);
3c997079
MD		 320
321 /* Set transient enabler state to "disabled" */
322 session->tstate = 0;
b2bc0bc8 323 lttng_session_sync_event_enablers(session);
64af2437
MD		 324
325 /* Set each stream's quiescent state. */
09b93db9
MD		 326 list_for_each_entry(chan, &session->chan, list) {
327 if (chan->channel_type != METADATA_CHANNEL)
328 lib_ring_buffer_set_quiescent_channel(chan->chan);
329 }
c0e31d2e
MD		 330end:
331 mutex_unlock(&sessions_mutex);
11b5a3c2 332 return ret;
c0e31d2e
MD		 333}
334
9616f0bf
JD		 335int lttng_session_metadata_regenerate(struct lttng_session *session)
336{
337 int ret = 0;
338 struct lttng_channel *chan;
339 struct lttng_event *event;
340 struct lttng_metadata_cache *cache = session->metadata_cache;
341 struct lttng_metadata_stream *stream;
342
343 mutex_lock(&sessions_mutex);
344 if (!session->active) {
345 ret = -EBUSY;
346 goto end;
347 }
348
349 mutex_lock(&cache->lock);
350 memset(cache->data, 0, cache->cache_alloc);
351 cache->metadata_written = 0;
352 cache->version++;
353 list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list) {
354 stream->metadata_out = 0;
355 stream->metadata_in = 0;
356 }
357 mutex_unlock(&cache->lock);
358
359 session->metadata_dumped = 0;
360 list_for_each_entry(chan, &session->chan, list) {
361 chan->metadata_dumped = 0;
362 }
363
364 list_for_each_entry(event, &session->events, list) {
365 event->metadata_dumped = 0;
366 }
367
368 ret = _lttng_session_metadata_statedump(session);
369
370end:
371 mutex_unlock(&sessions_mutex);
372 return ret;
373}
374
a90917c3 375int lttng_channel_enable(struct lttng_channel *channel)
e64957da 376{
3c997079 377 int ret = 0;
e64957da 378
3c997079
MD		 379 mutex_lock(&sessions_mutex);
380 if (channel->channel_type == METADATA_CHANNEL) {
381 ret = -EPERM;
382 goto end;
383 }
384 if (channel->enabled) {
385 ret = -EEXIST;
386 goto end;
387 }
388 /* Set transient enabler state to "enabled" */
389 channel->tstate = 1;
b2bc0bc8 390 lttng_session_sync_event_enablers(channel->session);
3c997079 391 /* Set atomically the state to "enabled" */
a8f2d0c7 392 WRITE_ONCE(channel->enabled, 1);
3c997079
MD		 393end:
394 mutex_unlock(&sessions_mutex);
395 return ret;
e64957da
MD		 396}
397
a90917c3 398int lttng_channel_disable(struct lttng_channel *channel)
e64957da 399{
3c997079 400 int ret = 0;
e64957da 401
3c997079
MD		 402 mutex_lock(&sessions_mutex);
403 if (channel->channel_type == METADATA_CHANNEL) {
404 ret = -EPERM;
405 goto end;
406 }
407 if (!channel->enabled) {
408 ret = -EEXIST;
409 goto end;
410 }
411 /* Set atomically the state to "disabled" */
a8f2d0c7 412 WRITE_ONCE(channel->enabled, 0);
3c997079
MD		 413 /* Set transient enabler state to "enabled" */
414 channel->tstate = 0;
b2bc0bc8 415 lttng_session_sync_event_enablers(channel->session);
3c997079
MD		 416end:
417 mutex_unlock(&sessions_mutex);
418 return ret;
e64957da
MD		 419}
420
a90917c3 421int lttng_event_enable(struct lttng_event *event)
e64957da 422{
3c997079 423 int ret = 0;
e64957da 424
3c997079
MD		 425 mutex_lock(&sessions_mutex);
426 if (event->chan->channel_type == METADATA_CHANNEL) {
427 ret = -EPERM;
428 goto end;
429 }
430 if (event->enabled) {
431 ret = -EEXIST;
432 goto end;
433 }
a0493bef
MD		 434 switch (event->instrumentation) {
435 case LTTNG_KERNEL_TRACEPOINT:
436 case LTTNG_KERNEL_SYSCALL:
437 ret = -EINVAL;
438 break;
439 case LTTNG_KERNEL_KPROBE:
149b9a9d 440 case LTTNG_KERNEL_UPROBE:
a0493bef 441 case LTTNG_KERNEL_NOOP:
a8f2d0c7 442 WRITE_ONCE(event->enabled, 1);
a0493bef
MD		 443 break;
444 case LTTNG_KERNEL_KRETPROBE:
445 ret = lttng_kretprobes_event_enable_state(event, 1);
446 break;
e884017c 447 case LTTNG_KERNEL_FUNCTION: /* Fall-through. */
a0493bef
MD		 448 default:
449 WARN_ON_ONCE(1);
450 ret = -EINVAL;
451 }
3c997079
MD		 452end:
453 mutex_unlock(&sessions_mutex);
454 return ret;
e64957da
MD		 455}
456
a90917c3 457int lttng_event_disable(struct lttng_event *event)
e64957da 458{
3c997079 459 int ret = 0;
e64957da 460
3c997079
MD		 461 mutex_lock(&sessions_mutex);
462 if (event->chan->channel_type == METADATA_CHANNEL) {
463 ret = -EPERM;
464 goto end;
465 }
466 if (!event->enabled) {
467 ret = -EEXIST;
468 goto end;
469 }
a0493bef
MD		 470 switch (event->instrumentation) {
471 case LTTNG_KERNEL_TRACEPOINT:
472 case LTTNG_KERNEL_SYSCALL:
473 ret = -EINVAL;
474 break;
475 case LTTNG_KERNEL_KPROBE:
149b9a9d 476 case LTTNG_KERNEL_UPROBE:
a0493bef 477 case LTTNG_KERNEL_NOOP:
a8f2d0c7 478 WRITE_ONCE(event->enabled, 0);
a0493bef
MD		 479 break;
480 case LTTNG_KERNEL_KRETPROBE:
481 ret = lttng_kretprobes_event_enable_state(event, 0);
482 break;
e884017c 483 case LTTNG_KERNEL_FUNCTION: /* Fall-through. */
a0493bef
MD		 484 default:
485 WARN_ON_ONCE(1);
486 ret = -EINVAL;
487 }
3c997079
MD		 488end:
489 mutex_unlock(&sessions_mutex);
490 return ret;
e64957da
MD		 491}
492
a90917c3 493struct lttng_channel *lttng_channel_create(struct lttng_session *session,
5dbbdb43
MD		 494 const char *transport_name,
495 void *buf_addr,
4e3c1b9b
MD		 496 size_t subbuf_size, size_t num_subbuf,
497 unsigned int switch_timer_interval,
d83004aa
JD		 498 unsigned int read_timer_interval,
499 enum channel_type channel_type)
4e3c1b9b 500{
a90917c3
MD		 501 struct lttng_channel *chan;
502 struct lttng_transport *transport = NULL;
4e3c1b9b
MD		 503
504 mutex_lock(&sessions_mutex);
d83004aa 505 if (session->been_active && channel_type != METADATA_CHANNEL)
e5382b6d 506 goto active; /* Refuse to add channel to active session */
a90917c3 507 transport = lttng_transport_find(transport_name);
f3d01b96 508 if (!transport) {
5a15f70c 509 printk(KERN_WARNING "LTTng: transport %s not found\n",
f3d01b96 510 transport_name);
c0e31d2e 511 goto notransport;
f3d01b96 512 }
a33c9927 513 if (!try_module_get(transport->owner)) {
5a15f70c 514 printk(KERN_WARNING "LTTng: Can't lock transport module.\n");
a33c9927
MD		 515 goto notransport;
516 }
a90917c3 517 chan = kzalloc(sizeof(struct lttng_channel), GFP_KERNEL);
4e3c1b9b 518 if (!chan)
c0e31d2e 519 goto nomem;
4e3c1b9b 520 chan->session = session;
05d32c64 521 chan->id = session->free_chan_id++;
3b731ab1 522 chan->ops = &transport->ops;
125b4df4
MD		 523 /*
524 * Note: the channel creation op already writes into the packet
525 * headers. Therefore the "chan" information used as input
526 * should be already accessible.
527 */
5f5ddf01
MD		 528 chan->chan = transport->ops.channel_create(transport_name,
529 chan, buf_addr, subbuf_size, num_subbuf,
530 switch_timer_interval, read_timer_interval);
f3d01b96
MD		 531 if (!chan->chan)
532 goto create_error;
3c997079 533 chan->tstate = 1;
e64957da 534 chan->enabled = 1;
a33c9927 535 chan->transport = transport;
d83004aa 536 chan->channel_type = channel_type;
4e3c1b9b
MD		 537 list_add(&chan->list, &session->chan);
538 mutex_unlock(&sessions_mutex);
539 return chan;
540
f3d01b96
MD		 541create_error:
542 kfree(chan);
c0e31d2e 543nomem:
a33c9927
MD		 544 if (transport)
545 module_put(transport->owner);
c0e31d2e 546notransport:
e5382b6d 547active:
4e3c1b9b
MD		 548 mutex_unlock(&sessions_mutex);
549 return NULL;
550}
551
552/*
d83004aa
JD		 553 * Only used internally at session destruction for per-cpu channels, and
554 * when metadata channel is released.
555 * Needs to be called with sessions mutex held.
4e3c1b9b 556 */
aa7c23a9 557static
a90917c3 558void _lttng_channel_destroy(struct lttng_channel *chan)
4e3c1b9b 559{
11b5a3c2 560 chan->ops->channel_destroy(chan->chan);
a33c9927 561 module_put(chan->transport->owner);
4e3c1b9b 562 list_del(&chan->list);
8070f5c0 563 lttng_destroy_context(chan->ctx);
4e3c1b9b
MD		 564 kfree(chan);
565}
566
d83004aa
JD		 567void lttng_metadata_channel_destroy(struct lttng_channel *chan)
568{
569 BUG_ON(chan->channel_type != METADATA_CHANNEL);
570
571 /* Protect the metadata cache with the sessions_mutex. */
572 mutex_lock(&sessions_mutex);
573 _lttng_channel_destroy(chan);
574 mutex_unlock(&sessions_mutex);
575}
576EXPORT_SYMBOL_GPL(lttng_metadata_channel_destroy);
577
578static
579void _lttng_metadata_channel_hangup(struct lttng_metadata_stream *stream)
580{
581 stream->finalized = 1;
582 wake_up_interruptible(&stream->read_wait);
583}
584
e5382b6d
MD		 585/*
586 * Supports event creation while tracing session is active.
3c997079 587 * Needs to be called with sessions mutex held.
e5382b6d 588 */
3c997079
MD		 589struct lttng_event *_lttng_event_create(struct lttng_channel *chan,
590 struct lttng_kernel_event *event_param,
591 void *filter,
592 const struct lttng_event_desc *event_desc,
593 enum lttng_kernel_instrumentation itype)
4e3c1b9b 594{
3c997079 595 struct lttng_session *session = chan->session;
a90917c3 596 struct lttng_event *event;
3c997079
MD		 597 const char *event_name;
598 struct hlist_head *head;
3d084699 599 int ret;
4e3c1b9b 600
abc0446a 601 if (chan->free_event_id == -1U) {
4cf0bf51 602 ret = -EMFILE;
e5382b6d 603 goto full;
abc0446a 604 }
3c997079
MD		 605
606 switch (itype) {
607 case LTTNG_KERNEL_TRACEPOINT:
608 event_name = event_desc->name;
609 break;
610 case LTTNG_KERNEL_KPROBE:
149b9a9d 611 case LTTNG_KERNEL_UPROBE:
3c997079 612 case LTTNG_KERNEL_KRETPROBE:
3c997079 613 case LTTNG_KERNEL_NOOP:
33a39a3c 614 case LTTNG_KERNEL_SYSCALL:
3c997079
MD		 615 event_name = event_param->name;
616 break;
e884017c 617 case LTTNG_KERNEL_FUNCTION: /* Fall-through. */
3c997079
MD		 618 default:
619 WARN_ON_ONCE(1);
620 ret = -EINVAL;
621 goto type_error;
622 }
4a11ef1c
FD		 623
624 head = utils_borrow_hash_table_bucket(session->events_ht.table,
625 LTTNG_EVENT_HT_SIZE, event_name);
d216ecae 626 lttng_hlist_for_each_entry(event, head, hlist) {
3c997079
MD		 627 WARN_ON_ONCE(!event->desc);
628 if (!strncmp(event->desc->name, event_name,
629 LTTNG_KERNEL_SYM_NAME_LEN - 1)
630 && chan == event->chan) {
631 ret = -EEXIST;
632 goto exist;
abc0446a
MD		 633 }
634 }
3c997079 635
11b5a3c2 636 event = kmem_cache_zalloc(event_cache, GFP_KERNEL);
abc0446a 637 if (!event) {
4cf0bf51 638 ret = -ENOMEM;
4e3c1b9b 639 goto cache_error;
abc0446a 640 }
4e3c1b9b
MD		 641 event->chan = chan;
642 event->filter = filter;
e5382b6d 643 event->id = chan->free_event_id++;
3c997079
MD		 644 event->instrumentation = itype;
645 event->evtype = LTTNG_TYPE_EVENT;
07dfc1d0 646 INIT_LIST_HEAD(&event->bytecode_runtime_head);
3c997079
MD		 647 INIT_LIST_HEAD(&event->enablers_ref_head);
648
649 switch (itype) {
ab2277d6 650 case LTTNG_KERNEL_TRACEPOINT:
3c997079
MD		 651 /* Event will be enabled by enabler sync. */
652 event->enabled = 0;
653 event->registered = 0;
0bcedee9 654 event->desc = lttng_event_desc_get(event_name);
abc0446a 655 if (!event->desc) {
4cf0bf51 656 ret = -ENOENT;
d3dbe23c 657 goto register_error;
abc0446a 658 }
3c997079
MD		 659 /* Populate lttng_event structure before event registration. */
660 smp_wmb();
baf20995 661 break;
ab2277d6 662 case LTTNG_KERNEL_KPROBE:
a0493bef
MD		 663 /*
664 * Needs to be explicitly enabled after creation, since
665 * we may want to apply filters.
666 */
667 event->enabled = 0;
3c997079
MD		 668 event->registered = 1;
669 /*
670 * Populate lttng_event structure before event
671 * registration.
672 */
673 smp_wmb();
674 ret = lttng_kprobes_register(event_name,
f17701fb
MD		 675 event_param->u.kprobe.symbol_name,
676 event_param->u.kprobe.offset,
677 event_param->u.kprobe.addr,
678 event);
abc0446a 679 if (ret) {
4cf0bf51 680 ret = -EINVAL;
d6d808f3 681 goto register_error;
abc0446a 682 }
edeb3137
MD		 683 ret = try_module_get(event->desc->owner);
684 WARN_ON_ONCE(!ret);
d6d808f3 685 break;
7371f44c
MD		 686 case LTTNG_KERNEL_KRETPROBE:
687 {
a90917c3 688 struct lttng_event *event_return;
7371f44c
MD		 689
690 /* kretprobe defines 2 events */
a0493bef
MD		 691 /*
692 * Needs to be explicitly enabled after creation, since
693 * we may want to apply filters.
694 */
695 event->enabled = 0;
3c997079 696 event->registered = 1;
7371f44c
MD		 697 event_return =
698 kmem_cache_zalloc(event_cache, GFP_KERNEL);
abc0446a 699 if (!event_return) {
4cf0bf51 700 ret = -ENOMEM;
7371f44c 701 goto register_error;
abc0446a 702 }
7371f44c
MD		 703 event_return->chan = chan;
704 event_return->filter = filter;
705 event_return->id = chan->free_event_id++;
a0493bef 706 event_return->enabled = 0;
3c997079
MD		 707 event_return->registered = 1;
708 event_return->instrumentation = itype;
7371f44c 709 /*
a90917c3 710 * Populate lttng_event structure before kretprobe registration.
7371f44c
MD		 711 */
712 smp_wmb();
3c997079 713 ret = lttng_kretprobes_register(event_name,
7371f44c
MD		 714 event_param->u.kretprobe.symbol_name,
715 event_param->u.kretprobe.offset,
716 event_param->u.kretprobe.addr,
717 event, event_return);
718 if (ret) {
719 kmem_cache_free(event_cache, event_return);
4cf0bf51 720 ret = -EINVAL;
7371f44c
MD		 721 goto register_error;
722 }
723 /* Take 2 refs on the module: one per event. */
724 ret = try_module_get(event->desc->owner);
725 WARN_ON_ONCE(!ret);
726 ret = try_module_get(event->desc->owner);
727 WARN_ON_ONCE(!ret);
a90917c3 728 ret = _lttng_event_metadata_statedump(chan->session, chan,
7371f44c 729 event_return);
abc0446a 730 WARN_ON_ONCE(ret > 0);
7371f44c
MD		 731 if (ret) {
732 kmem_cache_free(event_cache, event_return);
733 module_put(event->desc->owner);
734 module_put(event->desc->owner);
735 goto statedump_error;
736 }
737 list_add(&event_return->list, &chan->session->events);
738 break;
739 }
1ec65de1 740 case LTTNG_KERNEL_NOOP:
33a39a3c 741 case LTTNG_KERNEL_SYSCALL:
a0493bef
MD		 742 /*
743 * Needs to be explicitly enabled after creation, since
744 * we may want to apply filters.
745 */
746 event->enabled = 0;
3c997079
MD		 747 event->registered = 0;
748 event->desc = event_desc;
badfe9f5
MD		 749 switch (event_param->u.syscall.entryexit) {
750 case LTTNG_KERNEL_SYSCALL_ENTRYEXIT:
751 ret = -EINVAL;
752 goto register_error;
753 case LTTNG_KERNEL_SYSCALL_ENTRY:
754 event->u.syscall.entryexit = LTTNG_SYSCALL_ENTRY;
755 break;
756 case LTTNG_KERNEL_SYSCALL_EXIT:
757 event->u.syscall.entryexit = LTTNG_SYSCALL_EXIT;
758 break;
759 }
760 switch (event_param->u.syscall.abi) {
761 case LTTNG_KERNEL_SYSCALL_ABI_ALL:
762 ret = -EINVAL;
763 goto register_error;
764 case LTTNG_KERNEL_SYSCALL_ABI_NATIVE:
765 event->u.syscall.abi = LTTNG_SYSCALL_ABI_NATIVE;
766 break;
767 case LTTNG_KERNEL_SYSCALL_ABI_COMPAT:
768 event->u.syscall.abi = LTTNG_SYSCALL_ABI_COMPAT;
769 break;
770 }
abc0446a 771 if (!event->desc) {
4cf0bf51 772 ret = -EINVAL;
259b6cb3 773 goto register_error;
abc0446a 774 }
1ec65de1 775 break;
149b9a9d 776 case LTTNG_KERNEL_UPROBE:
a344f64b
FD		 777 /*
778 * Needs to be explicitly enabled after creation, since
779 * we may want to apply filters.
780 */
781 event->enabled = 0;
782 event->registered = 1;
3aed4dca 783
a344f64b
FD		 784 /*
785 * Populate lttng_event structure before event
786 * registration.
787 */
788 smp_wmb();
149b9a9d
YB		 789
790 ret = lttng_uprobes_register(event_param->name,
56377c91 791 event_param->u.uprobe.fd,
149b9a9d
YB		 792 event);
793 if (ret)
794 goto register_error;
795 ret = try_module_get(event->desc->owner);
796 WARN_ON_ONCE(!ret);
797 break;
e884017c 798 case LTTNG_KERNEL_FUNCTION: /* Fall-through */
baf20995
MD		 799 default:
800 WARN_ON_ONCE(1);
4cf0bf51 801 ret = -EINVAL;
df07930b 802 goto register_error;
baf20995 803 }
a90917c3 804 ret = _lttng_event_metadata_statedump(chan->session, chan, event);
abc0446a
MD		 805 WARN_ON_ONCE(ret > 0);
806 if (ret) {
c099397a 807 goto statedump_error;
abc0446a 808 }
3c997079 809 hlist_add_head(&event->hlist, head);
dda6a249 810 list_add(&event->list, &chan->session->events);
4e3c1b9b
MD		 811 return event;
812
c099397a 813statedump_error:
259b6cb3 814 /* If a statedump error occurs, events will not be readable. */
11b5a3c2 815register_error:
11b5a3c2 816 kmem_cache_free(event_cache, event);
4e3c1b9b
MD		 817cache_error:
818exist:
3c997079 819type_error:
e5382b6d 820full:
4cf0bf51 821 return ERR_PTR(ret);
4e3c1b9b
MD		 822}
823
3c997079
MD		 824struct lttng_event *lttng_event_create(struct lttng_channel *chan,
825 struct lttng_kernel_event *event_param,
826 void *filter,
827 const struct lttng_event_desc *event_desc,
828 enum lttng_kernel_instrumentation itype)
829{
830 struct lttng_event *event;
831
832 mutex_lock(&sessions_mutex);
833 event = _lttng_event_create(chan, event_param, filter, event_desc,
834 itype);
835 mutex_unlock(&sessions_mutex);
836 return event;
837}
838
839/* Only used for tracepoints for now. */
840static
841void register_event(struct lttng_event *event)
842{
843 const struct lttng_event_desc *desc;
f127e61e 844 int ret = -EINVAL;
3c997079 845
3c997079
MD		 846 if (event->registered)
847 return;
4ecb5ad5 848
3c997079 849 desc = event->desc;
4ecb5ad5
MD		 850 switch (event->instrumentation) {
851 case LTTNG_KERNEL_TRACEPOINT:
852 ret = lttng_wrapper_tracepoint_probe_register(desc->kname,
853 desc->probe_callback,
854 event);
855 break;
856 case LTTNG_KERNEL_SYSCALL:
badfe9f5 857 ret = lttng_syscall_filter_enable(event->chan, event);
4ecb5ad5
MD		 858 break;
859 case LTTNG_KERNEL_KPROBE:
a344f64b 860 case LTTNG_KERNEL_UPROBE:
4ecb5ad5 861 case LTTNG_KERNEL_KRETPROBE:
4ecb5ad5
MD		 862 case LTTNG_KERNEL_NOOP:
863 ret = 0;
864 break;
e884017c 865 case LTTNG_KERNEL_FUNCTION: /* Fall-through */
4ecb5ad5
MD		 866 default:
867 WARN_ON_ONCE(1);
868 }
3c997079
MD		 869 if (!ret)
870 event->registered = 1;
871}
872
4e3c1b9b
MD		 873/*
874 * Only used internally at session destruction.
875 */
a90917c3 876int _lttng_event_unregister(struct lttng_event *event)
4e3c1b9b 877{
4ecb5ad5 878 const struct lttng_event_desc *desc;
11b5a3c2
MD		 879 int ret = -EINVAL;
880
3c997079
MD		 881 if (!event->registered)
882 return 0;
883
4ecb5ad5 884 desc = event->desc;
38d024ae 885 switch (event->instrumentation) {
ab2277d6 886 case LTTNG_KERNEL_TRACEPOINT:
20591cf7 887 ret = lttng_wrapper_tracepoint_probe_unregister(event->desc->kname,
85a9ca7f 888 event->desc->probe_callback,
11b5a3c2 889 event);
baf20995 890 break;
ab2277d6 891 case LTTNG_KERNEL_KPROBE:
f17701fb 892 lttng_kprobes_unregister(event);
d6d808f3
MD		 893 ret = 0;
894 break;
7371f44c
MD		 895 case LTTNG_KERNEL_KRETPROBE:
896 lttng_kretprobes_unregister(event);
897 ret = 0;
898 break;
33a39a3c 899 case LTTNG_KERNEL_SYSCALL:
badfe9f5 900 ret = lttng_syscall_filter_disable(event->chan, event);
4ecb5ad5
MD		 901 break;
902 case LTTNG_KERNEL_NOOP:
259b6cb3
MD		 903 ret = 0;
904 break;
149b9a9d
YB		 905 case LTTNG_KERNEL_UPROBE:
906 lttng_uprobes_unregister(event);
907 ret = 0;
908 break;
e884017c 909 case LTTNG_KERNEL_FUNCTION: /* Fall-through */
baf20995
MD		 910 default:
911 WARN_ON_ONCE(1);
912 }
3c997079
MD		 913 if (!ret)
914 event->registered = 0;
dda6a249
MD		 915 return ret;
916}
917
918/*
919 * Only used internally at session destruction.
920 */
be066e6c 921static
a90917c3 922void _lttng_event_destroy(struct lttng_event *event)
dda6a249 923{
edeb3137
MD		 924 switch (event->instrumentation) {
925 case LTTNG_KERNEL_TRACEPOINT:
0bcedee9 926 lttng_event_desc_put(event->desc);
edeb3137
MD		 927 break;
928 case LTTNG_KERNEL_KPROBE:
929 module_put(event->desc->owner);
930 lttng_kprobes_destroy_private(event);
931 break;
7371f44c
MD		 932 case LTTNG_KERNEL_KRETPROBE:
933 module_put(event->desc->owner);
934 lttng_kretprobes_destroy_private(event);
935 break;
259b6cb3 936 case LTTNG_KERNEL_NOOP:
33a39a3c 937 case LTTNG_KERNEL_SYSCALL:
259b6cb3 938 break;
149b9a9d
YB		 939 case LTTNG_KERNEL_UPROBE:
940 module_put(event->desc->owner);
941 lttng_uprobes_destroy_private(event);
942 break;
e884017c 943 case LTTNG_KERNEL_FUNCTION: /* Fall-through */
edeb3137
MD		 944 default:
945 WARN_ON_ONCE(1);
946 }
dda6a249 947 list_del(&event->list);
8070f5c0 948 lttng_destroy_context(event->ctx);
11b5a3c2 949 kmem_cache_free(event_cache, event);
4e3c1b9b
MD		 950}
951
d1f652f8
MD		 952struct lttng_id_tracker *get_tracker(struct lttng_session *session,
953 enum tracker_type tracker_type)
e0130fab 954{
d1f652f8
MD		 955 switch (tracker_type) {
956 case TRACKER_PID:
957 return &session->pid_tracker;
958 case TRACKER_VPID:
959 return &session->vpid_tracker;
960 case TRACKER_UID:
961 return &session->uid_tracker;
962 case TRACKER_VUID:
963 return &session->vuid_tracker;
964 case TRACKER_GID:
965 return &session->gid_tracker;
966 case TRACKER_VGID:
967 return &session->vgid_tracker;
968 default:
969 WARN_ON_ONCE(1);
970 return NULL;
971 }
972}
973
974int lttng_session_track_id(struct lttng_session *session,
975 enum tracker_type tracker_type, int id)
976{
977 struct lttng_id_tracker *tracker;
e0130fab
MD		 978 int ret;
979
d1f652f8
MD		 980 tracker = get_tracker(session, tracker_type);
981 if (!tracker)
982 return -EINVAL;
983 if (id < -1)
e0130fab
MD		 984 return -EINVAL;
985 mutex_lock(&sessions_mutex);
d1f652f8
MD		 986 if (id == -1) {
987 /* track all ids: destroy tracker. */
988 lttng_id_tracker_destroy(tracker, true);
e0130fab
MD		 989 ret = 0;
990 } else {
d1f652f8 991 ret = lttng_id_tracker_add(tracker, id);
e0130fab 992 }
e0130fab
MD		 993 mutex_unlock(&sessions_mutex);
994 return ret;
995}
996
d1f652f8
MD		 997int lttng_session_untrack_id(struct lttng_session *session,
998 enum tracker_type tracker_type, int id)
e0130fab 999{
d1f652f8 1000 struct lttng_id_tracker *tracker;
e0130fab
MD		 1001 int ret;
1002
d1f652f8
MD		 1003 tracker = get_tracker(session, tracker_type);
1004 if (!tracker)
1005 return -EINVAL;
1006 if (id < -1)
e0130fab
MD		 1007 return -EINVAL;
1008 mutex_lock(&sessions_mutex);
d1f652f8
MD		 1009 if (id == -1) {
1010 /* untrack all ids: replace by empty tracker. */
1011 ret = lttng_id_tracker_empty_set(tracker);
e0130fab 1012 } else {
d1f652f8 1013 ret = lttng_id_tracker_del(tracker, id);
e0130fab 1014 }
e0130fab
MD		 1015 mutex_unlock(&sessions_mutex);
1016 return ret;
1017}
1018
7e6f9ef6 1019static
d1f652f8 1020void *id_list_start(struct seq_file *m, loff_t *pos)
7e6f9ef6 1021{
d1f652f8
MD		 1022 struct lttng_id_tracker *id_tracker = m->private;
1023 struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p;
1024 struct lttng_id_hash_node *e;
7e6f9ef6
MD		 1025 int iter = 0, i;
1026
1027 mutex_lock(&sessions_mutex);
d1f652f8
MD		 1028 if (id_tracker_p) {
1029 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1030 struct hlist_head *head = &id_tracker_p->id_hash[i];
7e6f9ef6 1031
f934e302 1032 lttng_hlist_for_each_entry(e, head, hlist) {
7e6f9ef6
MD		 1033 if (iter++ >= *pos)
1034 return e;
1035 }
1036 }
1037 } else {
d1f652f8 1038 /* ID tracker disabled. */
7e6f9ef6 1039 if (iter >= *pos && iter == 0) {
d1f652f8 1040 return id_tracker_p; /* empty tracker */
7e6f9ef6
MD		 1041 }
1042 iter++;
1043 }
1044 /* End of list */
1045 return NULL;
1046}
1047
1048/* Called with sessions_mutex held. */
1049static
d1f652f8 1050void *id_list_next(struct seq_file *m, void *p, loff_t *ppos)
7e6f9ef6 1051{
d1f652f8
MD		 1052 struct lttng_id_tracker *id_tracker = m->private;
1053 struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p;
1054 struct lttng_id_hash_node *e;
7e6f9ef6
MD		 1055 int iter = 0, i;
1056
1057 (*ppos)++;
d1f652f8
MD		 1058 if (id_tracker_p) {
1059 for (i = 0; i < LTTNG_ID_TABLE_SIZE; i++) {
1060 struct hlist_head *head = &id_tracker_p->id_hash[i];
7e6f9ef6 1061
f934e302 1062 lttng_hlist_for_each_entry(e, head, hlist) {
7e6f9ef6
MD		 1063 if (iter++ >= *ppos)
1064 return e;
1065 }
1066 }
1067 } else {
d1f652f8 1068 /* ID tracker disabled. */
7e6f9ef6 1069 if (iter >= *ppos && iter == 0)
d1f652f8 1070 return p; /* empty tracker */
7e6f9ef6
MD		 1071 iter++;
1072 }
1073
1074 /* End of list */
1075 return NULL;
1076}
1077
1078static
d1f652f8 1079void id_list_stop(struct seq_file *m, void *p)
7e6f9ef6
MD		 1080{
1081 mutex_unlock(&sessions_mutex);
1082}
1083
1084static
d1f652f8 1085int id_list_show(struct seq_file *m, void *p)
7e6f9ef6 1086{
d1f652f8
MD		 1087 struct lttng_id_tracker *id_tracker = m->private;
1088 struct lttng_id_tracker_rcu *id_tracker_p = id_tracker->p;
1089 int id;
7e6f9ef6 1090
d1f652f8 1091 if (p == id_tracker_p) {
7e6f9ef6 1092 /* Tracker disabled. */
d1f652f8 1093 id = -1;
7e6f9ef6 1094 } else {
d1f652f8 1095 const struct lttng_id_hash_node *e = p;
7e6f9ef6 1096
d1f652f8
MD		 1097 id = lttng_id_tracker_get_node_id(e);
1098 }
1099 switch (id_tracker->tracker_type) {
1100 case TRACKER_PID:
1101 seq_printf(m, "process { pid = %d; };\n", id);
1102 break;
1103 case TRACKER_VPID:
1104 seq_printf(m, "process { vpid = %d; };\n", id);
1105 break;
1106 case TRACKER_UID:
1107 seq_printf(m, "user { uid = %d; };\n", id);
1108 break;
1109 case TRACKER_VUID:
1110 seq_printf(m, "user { vuid = %d; };\n", id);
1111 break;
1112 case TRACKER_GID:
1113 seq_printf(m, "group { gid = %d; };\n", id);
1114 break;
1115 case TRACKER_VGID:
1116 seq_printf(m, "group { vgid = %d; };\n", id);
1117 break;
1118 default:
1119 seq_printf(m, "UNKNOWN { field = %d };\n", id);
7e6f9ef6 1120 }
7e6f9ef6
MD		 1121 return 0;
1122}
1123
1124static
d1f652f8
MD		 1125const struct seq_operations lttng_tracker_ids_list_seq_ops = {
1126 .start = id_list_start,
1127 .next = id_list_next,
1128 .stop = id_list_stop,
1129 .show = id_list_show,
7e6f9ef6
MD		 1130};
1131
1132static
d1f652f8 1133int lttng_tracker_ids_list_open(struct inode *inode, struct file *file)
7e6f9ef6 1134{
d1f652f8 1135 return seq_open(file, &lttng_tracker_ids_list_seq_ops);
7e6f9ef6
MD		 1136}
1137
1138static
d1f652f8 1139int lttng_tracker_ids_list_release(struct inode *inode, struct file *file)
7e6f9ef6
MD		 1140{
1141 struct seq_file *m = file->private_data;
d1f652f8 1142 struct lttng_id_tracker *id_tracker = m->private;
7e6f9ef6
MD		 1143 int ret;
1144
d1f652f8 1145 WARN_ON_ONCE(!id_tracker);
7e6f9ef6 1146 ret = seq_release(inode, file);
d1f652f8
MD		 1147 if (!ret)
1148 fput(id_tracker->session->file);
7e6f9ef6
MD		 1149 return ret;
1150}
1151
d1f652f8 1152const struct file_operations lttng_tracker_ids_list_fops = {
7e6f9ef6 1153 .owner = THIS_MODULE,
d1f652f8 1154 .open = lttng_tracker_ids_list_open,
7e6f9ef6
MD		 1155 .read = seq_read,
1156 .llseek = seq_lseek,
d1f652f8 1157 .release = lttng_tracker_ids_list_release,
7e6f9ef6
MD		 1158};
1159
d1f652f8
MD		 1160int lttng_session_list_tracker_ids(struct lttng_session *session,
1161 enum tracker_type tracker_type)
7e6f9ef6 1162{
d1f652f8 1163 struct file *tracker_ids_list_file;
7e6f9ef6
MD		 1164 struct seq_file *m;
1165 int file_fd, ret;
1166
1167 file_fd = lttng_get_unused_fd();
1168 if (file_fd < 0) {
1169 ret = file_fd;
1170 goto fd_error;
1171 }
1172
d1f652f8
MD		 1173 tracker_ids_list_file = anon_inode_getfile("[lttng_tracker_ids_list]",
1174 &lttng_tracker_ids_list_fops,
7e6f9ef6 1175 NULL, O_RDWR);
d1f652f8
MD		 1176 if (IS_ERR(tracker_ids_list_file)) {
1177 ret = PTR_ERR(tracker_ids_list_file);
7e6f9ef6
MD		 1178 goto file_error;
1179 }
98d7281c
MJ		 1180 if (!atomic_long_add_unless(&session->file->f_count, 1, LONG_MAX)) {
1181 ret = -EOVERFLOW;
9c1f4643
MD		 1182 goto refcount_error;
1183 }
d1f652f8 1184 ret = lttng_tracker_ids_list_fops.open(NULL, tracker_ids_list_file);
7e6f9ef6
MD		 1185 if (ret < 0)
1186 goto open_error;
d1f652f8
MD		 1187 m = tracker_ids_list_file->private_data;
1188
1189 m->private = get_tracker(session, tracker_type);
1190 BUG_ON(!m->private);
1191 fd_install(file_fd, tracker_ids_list_file);
7e6f9ef6
MD		 1192
1193 return file_fd;
1194
1195open_error:
9c1f4643
MD		 1196 atomic_long_dec(&session->file->f_count);
1197refcount_error:
d1f652f8 1198 fput(tracker_ids_list_file);
7e6f9ef6
MD		 1199file_error:
1200 put_unused_fd(file_fd);
1201fd_error:
1202 return ret;
1203}
1204
3c997079
MD		 1205/*
1206 * Enabler management.
1207 */
1208static
4993071a
PP		 1209int lttng_match_enabler_star_glob(const char *desc_name,
1210 const char *pattern)
3c997079 1211{
cbc19040
MD		 1212 if (!strutils_star_glob_match(pattern, LTTNG_SIZE_MAX,
1213 desc_name, LTTNG_SIZE_MAX))
3c997079
MD		 1214 return 0;
1215 return 1;
1216}
1217
1218static
4ecb5ad5
MD		 1219int lttng_match_enabler_name(const char *desc_name,
1220 const char *name)
3c997079 1221{
4ecb5ad5 1222 if (strcmp(desc_name, name))
3c997079
MD		 1223 return 0;
1224 return 1;
1225}
1226
1227static
1228int lttng_desc_match_enabler(const struct lttng_event_desc *desc,
1229 struct lttng_enabler *enabler)
1230{
4ecb5ad5 1231 const char *desc_name, *enabler_name;
badfe9f5 1232 bool compat = false, entry = false;
4ecb5ad5
MD		 1233
1234 enabler_name = enabler->event_param.name;
1235 switch (enabler->event_param.instrumentation) {
1236 case LTTNG_KERNEL_TRACEPOINT:
1237 desc_name = desc->name;
3b861b22
FD		 1238 switch (enabler->format_type) {
1239 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
badfe9f5 1240 return lttng_match_enabler_star_glob(desc_name, enabler_name);
3b861b22 1241 case LTTNG_ENABLER_FORMAT_NAME:
badfe9f5
MD		 1242 return lttng_match_enabler_name(desc_name, enabler_name);
1243 default:
1244 return -EINVAL;
1245 }
4ecb5ad5
MD		 1246 break;
1247 case LTTNG_KERNEL_SYSCALL:
1248 desc_name = desc->name;
badfe9f5 1249 if (!strncmp(desc_name, "compat_", strlen("compat_"))) {
4ecb5ad5 1250 desc_name += strlen("compat_");
badfe9f5
MD		 1251 compat = true;
1252 }
4ecb5ad5
MD		 1253 if (!strncmp(desc_name, "syscall_exit_",
1254 strlen("syscall_exit_"))) {
1255 desc_name += strlen("syscall_exit_");
1256 } else if (!strncmp(desc_name, "syscall_entry_",
1257 strlen("syscall_entry_"))) {
1258 desc_name += strlen("syscall_entry_");
badfe9f5 1259 entry = true;
4ecb5ad5
MD		 1260 } else {
1261 WARN_ON_ONCE(1);
1262 return -EINVAL;
1263 }
badfe9f5
MD		 1264 switch (enabler->event_param.u.syscall.entryexit) {
1265 case LTTNG_KERNEL_SYSCALL_ENTRYEXIT:
1266 break;
1267 case LTTNG_KERNEL_SYSCALL_ENTRY:
1268 if (!entry)
1269 return 0;
1270 break;
1271 case LTTNG_KERNEL_SYSCALL_EXIT:
1272 if (entry)
1273 return 0;
1274 break;
1275 default:
1276 return -EINVAL;
1277 }
1278 switch (enabler->event_param.u.syscall.abi) {
1279 case LTTNG_KERNEL_SYSCALL_ABI_ALL:
1280 break;
1281 case LTTNG_KERNEL_SYSCALL_ABI_NATIVE:
1282 if (compat)
1283 return 0;
1284 break;
1285 case LTTNG_KERNEL_SYSCALL_ABI_COMPAT:
1286 if (!compat)
1287 return 0;
1288 break;
1289 default:
1290 return -EINVAL;
1291 }
1292 switch (enabler->event_param.u.syscall.match) {
1293 case LTTNG_SYSCALL_MATCH_NAME:
3b861b22
FD		 1294 switch (enabler->format_type) {
1295 case LTTNG_ENABLER_FORMAT_STAR_GLOB:
badfe9f5 1296 return lttng_match_enabler_star_glob(desc_name, enabler_name);
3b861b22 1297 case LTTNG_ENABLER_FORMAT_NAME:
badfe9f5
MD		 1298 return lttng_match_enabler_name(desc_name, enabler_name);
1299 default:
1300 return -EINVAL;
1301 }
1302 break;
1303 case LTTNG_SYSCALL_MATCH_NR:
1304 return -EINVAL; /* Not implemented. */
1305 default:
1306 return -EINVAL;
1307 }
4ecb5ad5
MD		 1308 break;
1309 default:
1310 WARN_ON_ONCE(1);
1311 return -EINVAL;
1312 }
3c997079
MD		 1313}
1314
1315static
b2bc0bc8
FD		 1316int lttng_event_enabler_match_event(struct lttng_event_enabler *event_enabler,
1317 struct lttng_event *event)
3c997079 1318{
b2bc0bc8
FD		 1319 struct lttng_enabler *base_enabler = lttng_event_enabler_as_enabler(
1320 event_enabler);
1321
1322 if (base_enabler->event_param.instrumentation != event->instrumentation)
33a39a3c 1323 return 0;
b2bc0bc8
FD		 1324 if (lttng_desc_match_enabler(event->desc, base_enabler)
1325 && event->chan == event_enabler->chan)
3c997079
MD		 1326 return 1;
1327 else
1328 return 0;
1329}
1330
1331static
b2bc0bc8
FD		 1332struct lttng_enabler_ref *lttng_enabler_ref(
1333 struct list_head *enablers_ref_list,
3c997079
MD		 1334 struct lttng_enabler *enabler)
1335{
1336 struct lttng_enabler_ref *enabler_ref;
1337
b2bc0bc8 1338 list_for_each_entry(enabler_ref, enablers_ref_list, node) {
3c997079
MD		 1339 if (enabler_ref->ref == enabler)
1340 return enabler_ref;
1341 }
1342 return NULL;
1343}
1344
3c997079 1345static
1b917d6b 1346void lttng_create_tracepoint_event_if_missing(struct lttng_event_enabler *event_enabler)
3c997079 1347{
b2bc0bc8 1348 struct lttng_session *session = event_enabler->chan->session;
3c997079
MD		 1349 struct lttng_probe_desc *probe_desc;
1350 const struct lttng_event_desc *desc;
1351 int i;
1352 struct list_head *probe_list;
1353
1354 probe_list = lttng_get_probe_list_head();
1355 /*
1356 * For each probe event, if we find that a probe event matches
1357 * our enabler, create an associated lttng_event if not
1358 * already present.
1359 */
1360 list_for_each_entry(probe_desc, probe_list, head) {
1361 for (i = 0; i < probe_desc->nr_events; i++) {
1362 int found = 0;
1363 struct hlist_head *head;
3c997079
MD		 1364 struct lttng_event *event;
1365
1366 desc = probe_desc->event_desc[i];
b2bc0bc8
FD		 1367 if (!lttng_desc_match_enabler(desc,
1368 lttng_event_enabler_as_enabler(event_enabler)))
3c997079 1369 continue;
3c997079
MD		 1370
1371 /*
1372 * Check if already created.
1373 */
4a11ef1c
FD		 1374 head = utils_borrow_hash_table_bucket(
1375 session->events_ht.table, LTTNG_EVENT_HT_SIZE,
1376 desc->name);
d216ecae 1377 lttng_hlist_for_each_entry(event, head, hlist) {
3c997079 1378 if (event->desc == desc
b2bc0bc8 1379 && event->chan == event_enabler->chan)
3c997079
MD		 1380 found = 1;
1381 }
1382 if (found)
1383 continue;
1384
1385 /*
1386 * We need to create an event for this
1387 * event probe.
1388 */
b2bc0bc8 1389 event = _lttng_event_create(event_enabler->chan,
3c997079
MD		 1390 NULL, NULL, desc,
1391 LTTNG_KERNEL_TRACEPOINT);
1392 if (!event) {
5a15f70c 1393 printk(KERN_INFO "LTTng: Unable to create event %s\n",
3c997079
MD		 1394 probe_desc->event_desc[i]->name);
1395 }
1396 }
1397 }
1398}
1399
33a39a3c 1400static
1b917d6b 1401void lttng_create_syscall_event_if_missing(struct lttng_event_enabler *event_enabler)
33a39a3c
MD		 1402{
1403 int ret;
1404
b2bc0bc8 1405 ret = lttng_syscalls_register(event_enabler->chan, NULL);
33a39a3c
MD		 1406 WARN_ON_ONCE(ret);
1407}
1408
1409/*
1410 * Create struct lttng_event if it is missing and present in the list of
1411 * tracepoint probes.
1412 * Should be called with sessions mutex held.
1413 */
1414static
b2bc0bc8 1415void lttng_create_event_if_missing(struct lttng_event_enabler *event_enabler)
33a39a3c 1416{
b2bc0bc8 1417 switch (event_enabler->base.event_param.instrumentation) {
33a39a3c 1418 case LTTNG_KERNEL_TRACEPOINT:
1b917d6b 1419 lttng_create_tracepoint_event_if_missing(event_enabler);
33a39a3c
MD		 1420 break;
1421 case LTTNG_KERNEL_SYSCALL:
1b917d6b 1422 lttng_create_syscall_event_if_missing(event_enabler);
33a39a3c
MD		 1423 break;
1424 default:
1425 WARN_ON_ONCE(1);
1426 break;
1427 }
1428}
1429
3c997079 1430/*
b2bc0bc8 1431 * Create events associated with an event_enabler (if not already present),
3c997079
MD		 1432 * and add backward reference from the event to the enabler.
1433 * Should be called with sessions mutex held.
1434 */
1435static
b2bc0bc8 1436int lttng_event_enabler_ref_events(struct lttng_event_enabler *event_enabler)
3c997079 1437{
b2bc0bc8
FD		 1438 struct lttng_channel *chan = event_enabler->chan;
1439 struct lttng_session *session = event_enabler->chan->session;
1440 struct lttng_enabler *base_enabler = lttng_event_enabler_as_enabler(event_enabler);
3c997079
MD		 1441 struct lttng_event *event;
1442
b2bc0bc8
FD		 1443 if (base_enabler->event_param.instrumentation == LTTNG_KERNEL_SYSCALL &&
1444 base_enabler->event_param.u.syscall.entryexit == LTTNG_KERNEL_SYSCALL_ENTRYEXIT &&
1445 base_enabler->event_param.u.syscall.abi == LTTNG_KERNEL_SYSCALL_ABI_ALL &&
1446 base_enabler->event_param.u.syscall.match == LTTNG_SYSCALL_MATCH_NAME &&
1447 !strcmp(base_enabler->event_param.name, "*")) {
1448 if (base_enabler->enabled)
badfe9f5
MD		 1449 WRITE_ONCE(chan->syscall_all, 1);
1450 else
1451 WRITE_ONCE(chan->syscall_all, 0);
1452 }
1453
3c997079 1454 /* First ensure that probe events are created for this enabler. */
b2bc0bc8 1455 lttng_create_event_if_missing(event_enabler);
3c997079 1456
b2bc0bc8 1457 /* For each event matching event_enabler in session event list. */
3c997079
MD		 1458 list_for_each_entry(event, &session->events, list) {
1459 struct lttng_enabler_ref *enabler_ref;
1460
b2bc0bc8 1461 if (!lttng_event_enabler_match_event(event_enabler, event))
3c997079 1462 continue;
b2bc0bc8
FD		 1463 enabler_ref = lttng_enabler_ref(&event->enablers_ref_head,
1464 lttng_event_enabler_as_enabler(event_enabler));
3c997079
MD		 1465 if (!enabler_ref) {
1466 /*
1467 * If no backward ref, create it.
b2bc0bc8 1468 * Add backward ref from event to event_enabler.
3c997079
MD		 1469 */
1470 enabler_ref = kzalloc(sizeof(*enabler_ref), GFP_KERNEL);
1471 if (!enabler_ref)
1472 return -ENOMEM;
b2bc0bc8 1473 enabler_ref->ref = lttng_event_enabler_as_enabler(event_enabler);
3c997079
MD		 1474 list_add(&enabler_ref->node,
1475 &event->enablers_ref_head);
1476 }
1477
f127e61e
MD		 1478 /*
1479 * Link filter bytecodes if not linked yet.
1480 */
2dfda770
FD		 1481 lttng_enabler_link_bytecode(event->desc,
1482 lttng_static_ctx,
1483 &event->bytecode_runtime_head,
1484 lttng_event_enabler_as_enabler(event_enabler));
f127e61e 1485
3c997079
MD		 1486 /* TODO: merge event context. */
1487 }
1488 return 0;
1489}
1490
1491/*
1492 * Called at module load: connect the probe on all enablers matching
1493 * this event.
1494 * Called with sessions lock held.
1495 */
1496int lttng_fix_pending_events(void)
1497{
1498 struct lttng_session *session;
1499
1500 list_for_each_entry(session, &sessions, list)
b2bc0bc8 1501 lttng_session_lazy_sync_event_enablers(session);
3c997079
MD		 1502 return 0;
1503}
1504
b2bc0bc8
FD		 1505struct lttng_event_enabler *lttng_event_enabler_create(
1506 enum lttng_enabler_format_type format_type,
3c997079
MD		 1507 struct lttng_kernel_event *event_param,
1508 struct lttng_channel *chan)
1509{
b2bc0bc8 1510 struct lttng_event_enabler *event_enabler;
3c997079 1511
b2bc0bc8
FD		 1512 event_enabler = kzalloc(sizeof(*event_enabler), GFP_KERNEL);
1513 if (!event_enabler)
3c997079 1514 return NULL;
b2bc0bc8
FD		 1515 event_enabler->base.format_type = format_type;
1516 INIT_LIST_HEAD(&event_enabler->base.filter_bytecode_head);
1517 memcpy(&event_enabler->base.event_param, event_param,
1518 sizeof(event_enabler->base.event_param));
1519 event_enabler->chan = chan;
3c997079 1520 /* ctx left NULL */
b2bc0bc8
FD		 1521 event_enabler->base.enabled = 0;
1522 event_enabler->base.evtype = LTTNG_TYPE_ENABLER;
3c997079 1523 mutex_lock(&sessions_mutex);
b2bc0bc8
FD		 1524 list_add(&event_enabler->node, &event_enabler->chan->session->enablers_head);
1525 lttng_session_lazy_sync_event_enablers(event_enabler->chan->session);
3c997079 1526 mutex_unlock(&sessions_mutex);
b2bc0bc8 1527 return event_enabler;
3c997079
MD		 1528}
1529
b2bc0bc8 1530int lttng_event_enabler_enable(struct lttng_event_enabler *event_enabler)
3c997079
MD		 1531{
1532 mutex_lock(&sessions_mutex);
b2bc0bc8
FD		 1533 lttng_event_enabler_as_enabler(event_enabler)->enabled = 1;
1534 lttng_session_lazy_sync_event_enablers(event_enabler->chan->session);
3c997079
MD		 1535 mutex_unlock(&sessions_mutex);
1536 return 0;
1537}
1538
b2bc0bc8 1539int lttng_event_enabler_disable(struct lttng_event_enabler *event_enabler)
3c997079
MD		 1540{
1541 mutex_lock(&sessions_mutex);
b2bc0bc8
FD		 1542 lttng_event_enabler_as_enabler(event_enabler)->enabled = 0;
1543 lttng_session_lazy_sync_event_enablers(event_enabler->chan->session);
3c997079
MD		 1544 mutex_unlock(&sessions_mutex);
1545 return 0;
1546}
1547
b2bc0bc8 1548static
07dfc1d0
MD		 1549int lttng_enabler_attach_bytecode(struct lttng_enabler *enabler,
1550 struct lttng_kernel_filter_bytecode __user *bytecode)
1551{
1552 struct lttng_filter_bytecode_node *bytecode_node;
1553 uint32_t bytecode_len;
1554 int ret;
1555
1556 ret = get_user(bytecode_len, &bytecode->len);
1557 if (ret)
1558 return ret;
1559 bytecode_node = kzalloc(sizeof(*bytecode_node) + bytecode_len,
1560 GFP_KERNEL);
1561 if (!bytecode_node)
1562 return -ENOMEM;
1563 ret = copy_from_user(&bytecode_node->bc, bytecode,
1564 sizeof(*bytecode) + bytecode_len);
1565 if (ret)
1566 goto error_free;
b2bc0bc8 1567
07dfc1d0
MD		 1568 bytecode_node->enabler = enabler;
1569 /* Enforce length based on allocated size */
1570 bytecode_node->bc.len = bytecode_len;
1571 list_add_tail(&bytecode_node->node, &enabler->filter_bytecode_head);
b2bc0bc8 1572
07dfc1d0
MD		 1573 return 0;
1574
1575error_free:
1576 kfree(bytecode_node);
1577 return ret;
1578}
1579
b2bc0bc8
FD		 1580int lttng_event_enabler_attach_bytecode(struct lttng_event_enabler *event_enabler,
1581 struct lttng_kernel_filter_bytecode __user *bytecode)
1582{
1583 int ret;
1584 ret = lttng_enabler_attach_bytecode(
1585 lttng_event_enabler_as_enabler(event_enabler), bytecode);
1586 if (ret)
1587 goto error;
1588
1589 lttng_session_lazy_sync_event_enablers(event_enabler->chan->session);
1590 return 0;
1591
1592error:
1593 return ret;
1594}
1595
3aed4dca
FD		 1596int lttng_event_add_callsite(struct lttng_event *event,
1597 struct lttng_kernel_event_callsite __user *callsite)
1598{
1599
1600 switch (event->instrumentation) {
1601 case LTTNG_KERNEL_UPROBE:
1602 return lttng_uprobes_add_callsite(event, callsite);
1603 default:
1604 return -EINVAL;
1605 }
1606}
1607
b2bc0bc8 1608int lttng_event_enabler_attach_context(struct lttng_event_enabler *event_enabler,
3c997079
MD		 1609 struct lttng_kernel_context *context_param)
1610{
1611 return -ENOSYS;
1612}
1613
1614static
1615void lttng_enabler_destroy(struct lttng_enabler *enabler)
1616{
07dfc1d0
MD		 1617 struct lttng_filter_bytecode_node *filter_node, *tmp_filter_node;
1618
1619 /* Destroy filter bytecode */
1620 list_for_each_entry_safe(filter_node, tmp_filter_node,
1621 &enabler->filter_bytecode_head, node) {
1622 kfree(filter_node);
1623 }
b2bc0bc8
FD		 1624}
1625
1626static
1627void lttng_event_enabler_destroy(struct lttng_event_enabler *event_enabler)
1628{
1629 lttng_enabler_destroy(lttng_event_enabler_as_enabler(event_enabler));
07dfc1d0 1630
3c997079 1631 /* Destroy contexts */
b2bc0bc8 1632 lttng_destroy_context(event_enabler->ctx);
3c997079 1633
b2bc0bc8
FD		 1634 list_del(&event_enabler->node);
1635 kfree(event_enabler);
3c997079
MD		 1636}
1637
1638/*
b2bc0bc8 1639 * lttng_session_sync_event_enablers should be called just before starting a
3c997079
MD		 1640 * session.
1641 * Should be called with sessions mutex held.
1642 */
1643static
b2bc0bc8 1644void lttng_session_sync_event_enablers(struct lttng_session *session)
3c997079 1645{
b2bc0bc8 1646 struct lttng_event_enabler *event_enabler;
3c997079
MD		 1647 struct lttng_event *event;
1648
b2bc0bc8
FD		 1649 list_for_each_entry(event_enabler, &session->enablers_head, node)
1650 lttng_event_enabler_ref_events(event_enabler);
3c997079
MD		 1651 /*
1652 * For each event, if at least one of its enablers is enabled,
1653 * and its channel and session transient states are enabled, we
1654 * enable the event, else we disable it.
1655 */
1656 list_for_each_entry(event, &session->events, list) {
1657 struct lttng_enabler_ref *enabler_ref;
07dfc1d0
MD		 1658 struct lttng_bytecode_runtime *runtime;
1659 int enabled = 0, has_enablers_without_bytecode = 0;
3c997079 1660
4ecb5ad5
MD		 1661 switch (event->instrumentation) {
1662 case LTTNG_KERNEL_TRACEPOINT:
1663 case LTTNG_KERNEL_SYSCALL:
3c997079
MD		 1664 /* Enable events */
1665 list_for_each_entry(enabler_ref,
1666 &event->enablers_ref_head, node) {
1667 if (enabler_ref->ref->enabled) {
1668 enabled = 1;
1669 break;
1670 }
1671 }
4ecb5ad5
MD		 1672 break;
1673 default:
3c997079
MD		 1674 /* Not handled with lazy sync. */
1675 continue;
1676 }
1677 /*
1678 * Enabled state is based on union of enablers, with
1679 * intesection of session and channel transient enable
1680 * states.
1681 */
1682 enabled = enabled && session->tstate && event->chan->tstate;
1683
a8f2d0c7 1684 WRITE_ONCE(event->enabled, enabled);
3c997079
MD		 1685 /*
1686 * Sync tracepoint registration with event enabled
1687 * state.
1688 */
1689 if (enabled) {
1690 register_event(event);
1691 } else {
1692 _lttng_event_unregister(event);
1693 }
07dfc1d0
MD		 1694
1695 /* Check if has enablers without bytecode enabled */
1696 list_for_each_entry(enabler_ref,
1697 &event->enablers_ref_head, node) {
1698 if (enabler_ref->ref->enabled
1699 && list_empty(&enabler_ref->ref->filter_bytecode_head)) {
1700 has_enablers_without_bytecode = 1;
1701 break;
1702 }
1703 }
1704 event->has_enablers_without_bytecode =
1705 has_enablers_without_bytecode;
1706
1707 /* Enable filters */
1708 list_for_each_entry(runtime,
f127e61e 1709 &event->bytecode_runtime_head, node)
07dfc1d0 1710 lttng_filter_sync_state(runtime);
3c997079
MD		 1711 }
1712}
1713
1714/*
1715 * Apply enablers to session events, adding events to session if need
1716 * be. It is required after each modification applied to an active
1717 * session, and right before session "start".
1718 * "lazy" sync means we only sync if required.
1719 * Should be called with sessions mutex held.
1720 */
1721static
b2bc0bc8 1722void lttng_session_lazy_sync_event_enablers(struct lttng_session *session)
3c997079
MD		 1723{
1724 /* We can skip if session is not active */
1725 if (!session->active)
1726 return;
b2bc0bc8 1727 lttng_session_sync_event_enablers(session);
3c997079
MD		 1728}
1729
1ec3f75a 1730/*
d83004aa
JD		 1731 * Serialize at most one packet worth of metadata into a metadata
1732 * channel.
92d9f5e6
MD		 1733 * We grab the metadata cache mutex to get exclusive access to our metadata
1734 * buffer and to the metadata cache. Exclusive access to the metadata buffer
1735 * allows us to do racy operations such as looking for remaining space left in
1736 * packet and write, since mutual exclusion protects us from concurrent writes.
1737 * Mutual exclusion on the metadata cache allow us to read the cache content
1738 * without racing against reallocation of the cache by updates.
35097f36
JD		 1739 * Returns the number of bytes written in the channel, 0 if no data
1740 * was written and a negative value on error.
1ec3f75a 1741 */
b3b8072b 1742int lttng_metadata_output_channel(struct lttng_metadata_stream *stream,
8b97fd42 1743 struct channel *chan, bool *coherent)
d83004aa
JD		 1744{
1745 struct lib_ring_buffer_ctx ctx;
1746 int ret = 0;
1747 size_t len, reserve_len;
1748
f613e3e6 1749 /*
92d9f5e6
MD		 1750 * Ensure we support mutiple get_next / put sequences followed by
1751 * put_next. The metadata cache lock protects reading the metadata
1752 * cache. It can indeed be read concurrently by "get_next_subbuf" and
1753 * "flush" operations on the buffer invoked by different processes.
1754 * Moreover, since the metadata cache memory can be reallocated, we
1755 * need to have exclusive access against updates even though we only
1756 * read it.
f613e3e6 1757 */
92d9f5e6 1758 mutex_lock(&stream->metadata_cache->lock);
f613e3e6
MD		 1759 WARN_ON(stream->metadata_in < stream->metadata_out);
1760 if (stream->metadata_in != stream->metadata_out)
de23d59d 1761 goto end;
f613e3e6 1762
9616f0bf
JD		 1763 /* Metadata regenerated, change the version. */
1764 if (stream->metadata_cache->version != stream->version)
1765 stream->version = stream->metadata_cache->version;
1766
d83004aa 1767 len = stream->metadata_cache->metadata_written -
f613e3e6 1768 stream->metadata_in;
9de2c215 1769 if (!len)
de23d59d 1770 goto end;
d83004aa 1771 reserve_len = min_t(size_t,
b3b8072b 1772 stream->transport->ops.packet_avail_size(chan),
d83004aa 1773 len);
b3b8072b 1774 lib_ring_buffer_ctx_init(&ctx, chan, NULL, reserve_len,
d83004aa
JD		 1775 sizeof(char), -1);
1776 /*
1777 * If reservation failed, return an error to the caller.
1778 */
b3b8072b 1779 ret = stream->transport->ops.event_reserve(&ctx, 0);
d83004aa
JD		 1780 if (ret != 0) {
1781 printk(KERN_WARNING "LTTng: Metadata event reservation failed\n");
8b97fd42 1782 stream->coherent = false;
d83004aa
JD		 1783 goto end;
1784 }
b3b8072b 1785 stream->transport->ops.event_write(&ctx,
f613e3e6 1786 stream->metadata_cache->data + stream->metadata_in,
d83004aa 1787 reserve_len);
b3b8072b 1788 stream->transport->ops.event_commit(&ctx);
f613e3e6 1789 stream->metadata_in += reserve_len;
3e75e2a7 1790 if (reserve_len < len)
8b97fd42
MD		 1791 stream->coherent = false;
1792 else
1793 stream->coherent = true;
d83004aa
JD		 1794 ret = reserve_len;
1795
1796end:
8b97fd42
MD		 1797 if (coherent)
1798 *coherent = stream->coherent;
92d9f5e6 1799 mutex_unlock(&stream->metadata_cache->lock);
d83004aa
JD		 1800 return ret;
1801}
1802
8b97fd42
MD		 1803static
1804void lttng_metadata_begin(struct lttng_session *session)
1805{
3e75e2a7
MD		 1806 if (atomic_inc_return(&session->metadata_cache->producing) == 1)
1807 mutex_lock(&session->metadata_cache->lock);
8b97fd42
MD		 1808}
1809
1810static
1811void lttng_metadata_end(struct lttng_session *session)
1812{
3e75e2a7
MD		 1813 WARN_ON_ONCE(!atomic_read(&session->metadata_cache->producing));
1814 if (atomic_dec_return(&session->metadata_cache->producing) == 0) {
1815 struct lttng_metadata_stream *stream;
1816
3e75e2a7
MD		 1817 list_for_each_entry(stream, &session->metadata_cache->metadata_stream, list)
1818 wake_up_interruptible(&stream->read_wait);
92143b2c 1819 mutex_unlock(&session->metadata_cache->lock);
3e75e2a7 1820 }
8b97fd42
MD		 1821}
1822
d83004aa
JD		 1823/*
1824 * Write the metadata to the metadata cache.
1825 * Must be called with sessions_mutex held.
92d9f5e6
MD		 1826 * The metadata cache lock protects us from concurrent read access from
1827 * thread outputting metadata content to ring buffer.
8b97fd42
MD		 1828 * The content of the printf is printed as a single atomic metadata
1829 * transaction.
d83004aa 1830 */
a90917c3 1831int lttng_metadata_printf(struct lttng_session *session,
c099397a
MD		 1832 const char *fmt, ...)
1833{
c099397a 1834 char *str;
d83004aa 1835 size_t len;
c099397a
MD		 1836 va_list ap;
1837
585e5dcc 1838 WARN_ON_ONCE(!LTTNG_READ_ONCE(session->active));
c099397a
MD		 1839
1840 va_start(ap, fmt);
1841 str = kvasprintf(GFP_KERNEL, fmt, ap);
1842 va_end(ap);
1843 if (!str)
1844 return -ENOMEM;
1845
1ec3f75a 1846 len = strlen(str);
3e75e2a7 1847 WARN_ON_ONCE(!atomic_read(&session->metadata_cache->producing));
d83004aa
JD		 1848 if (session->metadata_cache->metadata_written + len >
1849 session->metadata_cache->cache_alloc) {
1850 char *tmp_cache_realloc;
1851 unsigned int tmp_cache_alloc_size;
1852
1853 tmp_cache_alloc_size = max_t(unsigned int,
1854 session->metadata_cache->cache_alloc + len,
1855 session->metadata_cache->cache_alloc << 1);
0ca42eb7 1856 tmp_cache_realloc = vzalloc(tmp_cache_alloc_size);
d83004aa
JD		 1857 if (!tmp_cache_realloc)
1858 goto err;
a606b6e8
ML		 1859 if (session->metadata_cache->data) {
1860 memcpy(tmp_cache_realloc,
1861 session->metadata_cache->data,
1862 session->metadata_cache->cache_alloc);
1863 vfree(session->metadata_cache->data);
1864 }
1865
d83004aa
JD		 1866 session->metadata_cache->cache_alloc = tmp_cache_alloc_size;
1867 session->metadata_cache->data = tmp_cache_realloc;
c099397a 1868 }
d83004aa
JD		 1869 memcpy(session->metadata_cache->data +
1870 session->metadata_cache->metadata_written,
1871 str, len);
1872 session->metadata_cache->metadata_written += len;
c099397a 1873 kfree(str);
d83004aa 1874
d83004aa
JD		 1875 return 0;
1876
1877err:
1878 kfree(str);
1879 return -ENOMEM;
c099397a
MD		 1880}
1881
f513b2bf
MD		 1882static
1883int print_tabs(struct lttng_session *session, size_t nesting)
1884{
1885 size_t i;
1886
1887 for (i = 0; i < nesting; i++) {
1888 int ret;
1889
1890 ret = lttng_metadata_printf(session, " ");
1891 if (ret) {
1892 return ret;
1893 }
1894 }
1895 return 0;
1896}
1897
ceabb767
MD		 1898static
1899int lttng_field_name_statedump(struct lttng_session *session,
1900 const struct lttng_event_field *field,
1901 size_t nesting)
1902{
1903 return lttng_metadata_printf(session, " _%s;\n", field->name);
1904}
1905
1906static
1907int _lttng_integer_type_statedump(struct lttng_session *session,
1908 const struct lttng_type *type,
1909 size_t nesting)
1910{
1911 int ret;
1912
1913 WARN_ON_ONCE(type->atype != atype_integer);
1914 ret = print_tabs(session, nesting);
1915 if (ret)
1916 return ret;
1917 ret = lttng_metadata_printf(session,
1918 "integer { size = %u; align = %u; signed = %u; encoding = %s; base = %u;%s }",
1919 type->u.integer.size,
1920 type->u.integer.alignment,
1921 type->u.integer.signedness,
1922 (type->u.integer.encoding == lttng_encode_none)
1923 ? "none"
1924 : (type->u.integer.encoding == lttng_encode_UTF8)
1925 ? "UTF8"
1926 : "ASCII",
1927 type->u.integer.base,
1928#if __BYTE_ORDER == __BIG_ENDIAN
1929 type->u.integer.reverse_byte_order ? " byte_order = le;" : ""
1930#else
1931 type->u.integer.reverse_byte_order ? " byte_order = be;" : ""
1932#endif
1933 );
1934 return ret;
1935}
1936
f513b2bf
MD		 1937/*
1938 * Must be called with sessions_mutex held.
1939 */
1940static
1941int _lttng_struct_type_statedump(struct lttng_session *session,
1942 const struct lttng_type *type,
1943 size_t nesting)
1944{
1945 int ret;
1946 uint32_t i, nr_fields;
ceabb767
MD		 1947 unsigned int alignment;
1948
1949 WARN_ON_ONCE(type->atype != atype_struct_nestable);
f513b2bf
MD		 1950
1951 ret = print_tabs(session, nesting);
1952 if (ret)
1953 return ret;
1954 ret = lttng_metadata_printf(session,
1955 "struct {\n");
1956 if (ret)
1957 return ret;
ceabb767 1958 nr_fields = type->u.struct_nestable.nr_fields;
f513b2bf
MD		 1959 for (i = 0; i < nr_fields; i++) {
1960 const struct lttng_event_field *iter_field;
1961
ceabb767 1962 iter_field = &type->u.struct_nestable.fields[i];
f513b2bf
MD		 1963 ret = _lttng_field_statedump(session, iter_field, nesting + 1);
1964 if (ret)
1965 return ret;
1966 }
1967 ret = print_tabs(session, nesting);
1968 if (ret)
1969 return ret;
ceabb767
MD		 1970 alignment = type->u.struct_nestable.alignment;
1971 if (alignment) {
1972 ret = lttng_metadata_printf(session,
1973 "} align(%u)",
1974 alignment);
1975 } else {
1976 ret = lttng_metadata_printf(session,
1977 "}");
1978 }
f513b2bf
MD		 1979 return ret;
1980}
1981
1982/*
1983 * Must be called with sessions_mutex held.
1984 */
1985static
ceabb767 1986int _lttng_struct_field_statedump(struct lttng_session *session,
f513b2bf
MD		 1987 const struct lttng_event_field *field,
1988 size_t nesting)
1989{
1990 int ret;
1991
1992 ret = _lttng_struct_type_statedump(session,
1993 &field->type, nesting);
1994 if (ret)
1995 return ret;
ceabb767 1996 return lttng_field_name_statedump(session, field, nesting);
f513b2bf
MD		 1997}
1998
65c85aa6
MD		 1999/*
2000 * Must be called with sessions_mutex held.
2001 */
2002static
2003int _lttng_variant_type_statedump(struct lttng_session *session,
2004 const struct lttng_type *type,
2005 size_t nesting)
2006{
2007 int ret;
2008 uint32_t i, nr_choices;
2009
ceabb767
MD		 2010 WARN_ON_ONCE(type->atype != atype_variant_nestable);
2011 /*
2012 * CTF 1.8 does not allow expressing nonzero variant alignment in a nestable way.
2013 */
2014 if (type->u.variant_nestable.alignment != 0)
2015 return -EINVAL;
65c85aa6
MD		 2016 ret = print_tabs(session, nesting);
2017 if (ret)
2018 return ret;
2019 ret = lttng_metadata_printf(session,
2020 "variant <_%s> {\n",
ceabb767 2021 type->u.variant_nestable.tag_name);
65c85aa6
MD		 2022 if (ret)
2023 return ret;
ceabb767 2024 nr_choices = type->u.variant_nestable.nr_choices;
65c85aa6
MD		 2025 for (i = 0; i < nr_choices; i++) {
2026 const struct lttng_event_field *iter_field;
2027
ceabb767 2028 iter_field = &type->u.variant_nestable.choices[i];
65c85aa6
MD		 2029 ret = _lttng_field_statedump(session, iter_field, nesting + 1);
2030 if (ret)
2031 return ret;
2032 }
2033 ret = print_tabs(session, nesting);
2034 if (ret)
2035 return ret;
2036 ret = lttng_metadata_printf(session,
2037 "}");
2038 return ret;
2039}
2040
2041/*
2042 * Must be called with sessions_mutex held.
2043 */
2044static
ceabb767 2045int _lttng_variant_field_statedump(struct lttng_session *session,
65c85aa6
MD		 2046 const struct lttng_event_field *field,
2047 size_t nesting)
2048{
2049 int ret;
2050
2051 ret = _lttng_variant_type_statedump(session,
2052 &field->type, nesting);
2053 if (ret)
2054 return ret;
ceabb767 2055 return lttng_field_name_statedump(session, field, nesting);
65c85aa6
MD		 2056}
2057
f513b2bf
MD		 2058/*
2059 * Must be called with sessions_mutex held.
2060 */
2061static
ceabb767 2062int _lttng_array_field_statedump(struct lttng_session *session,
f513b2bf
MD		 2063 const struct lttng_event_field *field,
2064 size_t nesting)
2065{
2066 int ret;
2067 const struct lttng_type *elem_type;
2068
ceabb767
MD		 2069 WARN_ON_ONCE(field->type.atype != atype_array_nestable);
2070
2071 if (field->type.u.array_nestable.alignment) {
2072 ret = print_tabs(session, nesting);
f513b2bf
MD		 2073 if (ret)
2074 return ret;
ceabb767
MD		 2075 ret = lttng_metadata_printf(session,
2076 "struct { } align(%u) _%s_padding;\n",
2077 field->type.u.array_nestable.alignment * CHAR_BIT,
2078 field->name);
2079 if (ret)
2080 return ret;
2081 }
2082 /*
2083 * Nested compound types: Only array of structures and variants are
2084 * currently supported.
2085 */
2086 elem_type = field->type.u.array_nestable.elem_type;
2087 switch (elem_type->atype) {
2088 case atype_integer:
2089 case atype_struct_nestable:
2090 case atype_variant_nestable:
2091 ret = _lttng_type_statedump(session, elem_type, nesting);
65c85aa6
MD		 2092 if (ret)
2093 return ret;
2094 break;
ceabb767 2095
f513b2bf
MD		 2096 default:
2097 return -EINVAL;
2098 }
2099 ret = lttng_metadata_printf(session,
2100 " _%s[%u];\n",
2101 field->name,
ceabb767 2102 field->type.u.array_nestable.length);
f513b2bf
MD		 2103 return ret;
2104}
2105
2106/*
2107 * Must be called with sessions_mutex held.
2108 */
2109static
ceabb767 2110int _lttng_sequence_field_statedump(struct lttng_session *session,
f513b2bf
MD		 2111 const struct lttng_event_field *field,
2112 size_t nesting)
2113{
2114 int ret;
2115 const char *length_name;
2116 const struct lttng_type *elem_type;
2117
ceabb767 2118 WARN_ON_ONCE(field->type.atype != atype_sequence_nestable);
f513b2bf 2119
ceabb767
MD		 2120 length_name = field->type.u.sequence_nestable.length_name;
2121
2122 if (field->type.u.sequence_nestable.alignment) {
2123 ret = print_tabs(session, nesting);
f513b2bf
MD		 2124 if (ret)
2125 return ret;
ceabb767
MD		 2126 ret = lttng_metadata_printf(session,
2127 "struct { } align(%u) _%s_padding;\n",
2128 field->type.u.sequence_nestable.alignment * CHAR_BIT,
2129 field->name);
2130 if (ret)
2131 return ret;
2132 }
2133
2134 /*
2135 * Nested compound types: Only array of structures and variants are
2136 * currently supported.
2137 */
2138 elem_type = field->type.u.sequence_nestable.elem_type;
2139 switch (elem_type->atype) {
2140 case atype_integer:
2141 case atype_struct_nestable:
2142 case atype_variant_nestable:
2143 ret = _lttng_type_statedump(session, elem_type, nesting);
65c85aa6
MD		 2144 if (ret)
2145 return ret;
2146 break;
ceabb767 2147
f513b2bf
MD		 2148 default:
2149 return -EINVAL;
2150 }
2151 ret = lttng_metadata_printf(session,
2152 " _%s[ _%s ];\n",
2153 field->name,
ceabb767 2154 field->type.u.sequence_nestable.length_name);
f513b2bf
MD		 2155 return ret;
2156}
2157
141ddf28
MD		 2158/*
2159 * Must be called with sessions_mutex held.
2160 */
2161static
ceabb767
MD		 2162int _lttng_enum_type_statedump(struct lttng_session *session,
2163 const struct lttng_type *type,
141ddf28
MD		 2164 size_t nesting)
2165{
2166 const struct lttng_enum_desc *enum_desc;
ceabb767 2167 const struct lttng_type *container_type;
141ddf28
MD		 2168 int ret;
2169 unsigned int i, nr_entries;
2170
ceabb767
MD		 2171 container_type = type->u.enum_nestable.container_type;
2172 if (container_type->atype != atype_integer) {
2173 ret = -EINVAL;
2174 goto end;
2175 }
2176 enum_desc = type->u.enum_nestable.desc;
141ddf28
MD		 2177 nr_entries = enum_desc->nr_entries;
2178
2179 ret = print_tabs(session, nesting);
2180 if (ret)
2181 goto end;
ceabb767
MD		 2182 ret = lttng_metadata_printf(session, "enum : ");
2183 if (ret)
2184 goto end;
2185 ret = _lttng_integer_type_statedump(session, container_type, 0);
141ddf28 2186 if (ret)
ceabb767
MD		 2187 goto end;
2188 ret = lttng_metadata_printf(session, " {\n");
2189 if (ret)
2190 goto end;
141ddf28
MD		 2191 /* Dump all entries */
2192 for (i = 0; i < nr_entries; i++) {
2193 const struct lttng_enum_entry *entry = &enum_desc->entries[i];
2194 int j, len;
2195
2196 ret = print_tabs(session, nesting + 1);
2197 if (ret)
2198 goto end;
2199 ret = lttng_metadata_printf(session,
2200 "\"");
2201 if (ret)
2202 goto end;
2203 len = strlen(entry->string);
2204 /* Escape the character '"' */
2205 for (j = 0; j < len; j++) {
2206 char c = entry->string[j];
2207
2208 switch (c) {
2209 case '"':
2210 ret = lttng_metadata_printf(session,
2211 "\\\"");
2212 break;
2213 case '\\':
2214 ret = lttng_metadata_printf(session,
2215 "\\\\");
2216 break;
2217 default:
2218 ret = lttng_metadata_printf(session,
2219 "%c", c);
2220 break;
2221 }
2222 if (ret)
2223 goto end;
2224 }
08ad1061
PP		 2225 ret = lttng_metadata_printf(session, "\"");
2226 if (ret)
2227 goto end;
2228
2229 if (entry->options.is_auto) {
2230 ret = lttng_metadata_printf(session, ",\n");
2231 if (ret)
2232 goto end;
141ddf28 2233 } else {
7c559490
MD		 2234 ret = lttng_metadata_printf(session,
2235 " = ");
2236 if (ret)
2237 goto end;
2238 if (entry->start.signedness)
141ddf28 2239 ret = lttng_metadata_printf(session,
7c559490
MD		 2240 "%lld", (long long) entry->start.value);
2241 else
2242 ret = lttng_metadata_printf(session,
2243 "%llu", entry->start.value);
2244 if (ret)
2245 goto end;
2246 if (entry->start.signedness == entry->end.signedness &&
2247 entry->start.value
2248 == entry->end.value) {
141ddf28 2249 ret = lttng_metadata_printf(session,
7c559490
MD		 2250 ",\n");
2251 } else {
2252 if (entry->end.signedness) {
2253 ret = lttng_metadata_printf(session,
2254 " ... %lld,\n",
2255 (long long) entry->end.value);
2256 } else {
2257 ret = lttng_metadata_printf(session,
2258 " ... %llu,\n",
2259 entry->end.value);
2260 }
141ddf28 2261 }
7c559490
MD		 2262 if (ret)
2263 goto end;
141ddf28 2264 }
141ddf28
MD		 2265 }
2266 ret = print_tabs(session, nesting);
2267 if (ret)
2268 goto end;
ceabb767 2269 ret = lttng_metadata_printf(session, "}");
141ddf28
MD		 2270end:
2271 return ret;
2272}
2273
d83004aa
JD		 2274/*
2275 * Must be called with sessions_mutex held.
2276 */
c099397a 2277static
ceabb767
MD		 2278int _lttng_enum_field_statedump(struct lttng_session *session,
2279 const struct lttng_event_field *field,
2280 size_t nesting)
2281{
2282 int ret;
2283
2284 ret = _lttng_enum_type_statedump(session, &field->type, nesting);
2285 if (ret)
2286 return ret;
2287 return lttng_field_name_statedump(session, field, nesting);
2288}
2289
2290static
2291int _lttng_integer_field_statedump(struct lttng_session *session,
2292 const struct lttng_event_field *field,
2293 size_t nesting)
2294{
2295 int ret;
2296
2297 ret = _lttng_integer_type_statedump(session, &field->type, nesting);
2298 if (ret)
2299 return ret;
2300 return lttng_field_name_statedump(session, field, nesting);
2301}
2302
2303static
2304int _lttng_string_type_statedump(struct lttng_session *session,
2305 const struct lttng_type *type,
2306 size_t nesting)
2307{
2308 int ret;
2309
2310 WARN_ON_ONCE(type->atype != atype_string);
2311 /* Default encoding is UTF8 */
2312 ret = print_tabs(session, nesting);
2313 if (ret)
2314 return ret;
2315 ret = lttng_metadata_printf(session,
2316 "string%s",
2317 type->u.string.encoding == lttng_encode_ASCII ?
2318 " { encoding = ASCII; }" : "");
2319 return ret;
2320}
2321
2322static
2323int _lttng_string_field_statedump(struct lttng_session *session,
f513b2bf
MD		 2324 const struct lttng_event_field *field,
2325 size_t nesting)
ceabb767
MD		 2326{
2327 int ret;
2328
2329 WARN_ON_ONCE(field->type.atype != atype_string);
2330 ret = _lttng_string_type_statedump(session, &field->type, nesting);
2331 if (ret)
2332 return ret;
2333 return lttng_field_name_statedump(session, field, nesting);
2334}
2335
2336/*
2337 * Must be called with sessions_mutex held.
2338 */
2339static
2340int _lttng_type_statedump(struct lttng_session *session,
2341 const struct lttng_type *type,
2342 size_t nesting)
c099397a 2343{
c099397a 2344 int ret = 0;
c099397a 2345
ceabb767 2346 switch (type->atype) {
8070f5c0 2347 case atype_integer:
ceabb767 2348 ret = _lttng_integer_type_statedump(session, type, nesting);
8070f5c0 2349 break;
ceabb767
MD		 2350 case atype_enum_nestable:
2351 ret = _lttng_enum_type_statedump(session, type, nesting);
8070f5c0 2352 break;
ceabb767
MD		 2353 case atype_string:
2354 ret = _lttng_string_type_statedump(session, type, nesting);
2355 break;
2356 case atype_struct_nestable:
2357 ret = _lttng_struct_type_statedump(session, type, nesting);
8070f5c0 2358 break;
ceabb767
MD		 2359 case atype_variant_nestable:
2360 ret = _lttng_variant_type_statedump(session, type, nesting);
2361 break;
2362
2363 /* Nested arrays and sequences are not supported yet. */
2364 case atype_array_nestable:
2365 case atype_sequence_nestable:
2366 default:
2367 WARN_ON_ONCE(1);
2368 return -EINVAL;
8070f5c0 2369 }
ceabb767
MD		 2370 return ret;
2371}
8070f5c0 2372
ceabb767
MD		 2373/*
2374 * Must be called with sessions_mutex held.
2375 */
2376static
2377int _lttng_field_statedump(struct lttng_session *session,
2378 const struct lttng_event_field *field,
2379 size_t nesting)
2380{
2381 int ret = 0;
27d2368e 2382
ceabb767
MD		 2383 switch (field->type.atype) {
2384 case atype_integer:
2385 ret = _lttng_integer_field_statedump(session, field, nesting);
2386 break;
2387 case atype_enum_nestable:
2388 ret = _lttng_enum_field_statedump(session, field, nesting);
8070f5c0 2389 break;
8070f5c0 2390 case atype_string:
ceabb767 2391 ret = _lttng_string_field_statedump(session, field, nesting);
8070f5c0 2392 break;
ceabb767
MD		 2393 case atype_struct_nestable:
2394 ret = _lttng_struct_field_statedump(session, field, nesting);
f513b2bf 2395 break;
ceabb767
MD		 2396 case atype_array_nestable:
2397 ret = _lttng_array_field_statedump(session, field, nesting);
f513b2bf 2398 break;
ceabb767
MD		 2399 case atype_sequence_nestable:
2400 ret = _lttng_sequence_field_statedump(session, field, nesting);
f513b2bf 2401 break;
ceabb767
MD		 2402 case atype_variant_nestable:
2403 ret = _lttng_variant_field_statedump(session, field, nesting);
65c85aa6 2404 break;
f513b2bf 2405
8070f5c0
MD		 2406 default:
2407 WARN_ON_ONCE(1);
2408 return -EINVAL;
2409 }
2410 return ret;
2411}
2412
2413static
a90917c3 2414int _lttng_context_metadata_statedump(struct lttng_session *session,
8070f5c0
MD		 2415 struct lttng_ctx *ctx)
2416{
2417 int ret = 0;
2418 int i;
2419
2420 if (!ctx)
2421 return 0;
2422 for (i = 0; i < ctx->nr_fields; i++) {
2423 const struct lttng_ctx_field *field = &ctx->fields[i];
2424
f513b2bf 2425 ret = _lttng_field_statedump(session, &field->event_field, 2);
8070f5c0
MD		 2426 if (ret)
2427 return ret;
2428 }
2429 return ret;
2430}
2431
2432static
a90917c3
MD		 2433int _lttng_fields_metadata_statedump(struct lttng_session *session,
2434 struct lttng_event *event)
8070f5c0
MD		 2435{
2436 const struct lttng_event_desc *desc = event->desc;
2437 int ret = 0;
2438 int i;
2439
2440 for (i = 0; i < desc->nr_fields; i++) {
2441 const struct lttng_event_field *field = &desc->fields[i];
2442
f513b2bf 2443 ret = _lttng_field_statedump(session, field, 2);
8070f5c0
MD		 2444 if (ret)
2445 return ret;
c099397a
MD		 2446 }
2447 return ret;
2448}
2449
d83004aa
JD		 2450/*
2451 * Must be called with sessions_mutex held.
8b97fd42
MD		 2452 * The entire event metadata is printed as a single atomic metadata
2453 * transaction.
d83004aa 2454 */
c099397a 2455static
a90917c3
MD		 2456int _lttng_event_metadata_statedump(struct lttng_session *session,
2457 struct lttng_channel *chan,
2458 struct lttng_event *event)
c099397a
MD		 2459{
2460 int ret = 0;
2461
585e5dcc 2462 if (event->metadata_dumped || !LTTNG_READ_ONCE(session->active))
c099397a 2463 return 0;
d83004aa 2464 if (chan->channel_type == METADATA_CHANNEL)
c099397a
MD		 2465 return 0;
2466
8b97fd42
MD		 2467 lttng_metadata_begin(session);
2468
c099397a
MD		 2469 ret = lttng_metadata_printf(session,
2470 "event {\n"
ae734547 2471 " name = \"%s\";\n"
c099397a 2472 " id = %u;\n"
b9074a1b 2473 " stream_id = %u;\n",
c099397a
MD		 2474 event->desc->name,
2475 event->id,
2476 event->chan->id);
2477 if (ret)
2478 goto end;
2479
b9074a1b
MD		 2480 if (event->ctx) {
2481 ret = lttng_metadata_printf(session,
2482 " context := struct {\n");
2483 if (ret)
2484 goto end;
2485 }
a90917c3 2486 ret = _lttng_context_metadata_statedump(session, event->ctx);
8070f5c0
MD		 2487 if (ret)
2488 goto end;
b9074a1b
MD		 2489 if (event->ctx) {
2490 ret = lttng_metadata_printf(session,
2491 " };\n");
2492 if (ret)
2493 goto end;
2494 }
8070f5c0
MD		 2495
2496 ret = lttng_metadata_printf(session,
8070f5c0
MD		 2497 " fields := struct {\n"
2498 );
2499 if (ret)
2500 goto end;
2501
a90917c3 2502 ret = _lttng_fields_metadata_statedump(session, event);
c099397a
MD		 2503 if (ret)
2504 goto end;
2505
2506 /*
2507 * LTTng space reservation can only reserve multiples of the
2508 * byte size.
2509 */
2510 ret = lttng_metadata_printf(session,
9115fbdc
MD		 2511 " };\n"
2512 "};\n\n");
c099397a
MD		 2513 if (ret)
2514 goto end;
2515
c099397a
MD		 2516 event->metadata_dumped = 1;
2517end:
8b97fd42 2518 lttng_metadata_end(session);
c099397a
MD		 2519 return ret;
2520
2521}
2522
d83004aa
JD		 2523/*
2524 * Must be called with sessions_mutex held.
8b97fd42
MD		 2525 * The entire channel metadata is printed as a single atomic metadata
2526 * transaction.
d83004aa 2527 */
c099397a 2528static
a90917c3
MD		 2529int _lttng_channel_metadata_statedump(struct lttng_session *session,
2530 struct lttng_channel *chan)
c099397a
MD		 2531{
2532 int ret = 0;
2533
585e5dcc 2534 if (chan->metadata_dumped || !LTTNG_READ_ONCE(session->active))
c099397a 2535 return 0;
d83004aa
JD		 2536
2537 if (chan->channel_type == METADATA_CHANNEL)
c099397a
MD		 2538 return 0;
2539
8b97fd42
MD		 2540 lttng_metadata_begin(session);
2541
c099397a
MD		 2542 WARN_ON_ONCE(!chan->header_type);
2543 ret = lttng_metadata_printf(session,
2544 "stream {\n"
2545 " id = %u;\n"
9115fbdc 2546 " event.header := %s;\n"
b9074a1b 2547 " packet.context := struct packet_context;\n",
c099397a
MD		 2548 chan->id,
2549 chan->header_type == 1 ? "struct event_header_compact" :
2550 "struct event_header_large");
2551 if (ret)
2552 goto end;
2553
b9074a1b
MD		 2554 if (chan->ctx) {
2555 ret = lttng_metadata_printf(session,
2556 " event.context := struct {\n");
2557 if (ret)
2558 goto end;
2559 }
a90917c3 2560 ret = _lttng_context_metadata_statedump(session, chan->ctx);
8070f5c0
MD		 2561 if (ret)
2562 goto end;
b9074a1b
MD		 2563 if (chan->ctx) {
2564 ret = lttng_metadata_printf(session,
2565 " };\n");
2566 if (ret)
2567 goto end;
2568 }
8070f5c0
MD		 2569
2570 ret = lttng_metadata_printf(session,
b9074a1b 2571 "};\n\n");
8070f5c0 2572
c099397a
MD		 2573 chan->metadata_dumped = 1;
2574end:
8b97fd42 2575 lttng_metadata_end(session);
c099397a
MD		 2576 return ret;
2577}
2578
d83004aa
JD		 2579/*
2580 * Must be called with sessions_mutex held.
2581 */
9115fbdc 2582static
a90917c3 2583int _lttng_stream_packet_context_declare(struct lttng_session *session)
9115fbdc
MD		 2584{
2585 return lttng_metadata_printf(session,
2586 "struct packet_context {\n"
a3ccff4f
MD		 2587 " uint64_clock_monotonic_t timestamp_begin;\n"
2588 " uint64_clock_monotonic_t timestamp_end;\n"
576ca06a
MD		 2589 " uint64_t content_size;\n"
2590 " uint64_t packet_size;\n"
5b3cf4f9 2591 " uint64_t packet_seq_num;\n"
a9afe705 2592 " unsigned long events_discarded;\n"
9115fbdc 2593 " uint32_t cpu_id;\n"
c6dfdf6f 2594 "};\n\n"
9115fbdc
MD		 2595 );
2596}
2597
2598/*
2599 * Compact header:
2600 * id: range: 0 - 30.
2601 * id 31 is reserved to indicate an extended header.
2602 *
2603 * Large header:
2604 * id: range: 0 - 65534.
2605 * id 65535 is reserved to indicate an extended header.
d83004aa
JD		 2606 *
2607 * Must be called with sessions_mutex held.
9115fbdc
MD		 2608 */
2609static
a90917c3 2610int _lttng_event_header_declare(struct lttng_session *session)
9115fbdc
MD		 2611{
2612 return lttng_metadata_printf(session,
2613 "struct event_header_compact {\n"
2614 " enum : uint5_t { compact = 0 ... 30, extended = 31 } id;\n"
2615 " variant <id> {\n"
2616 " struct {\n"
a3ccff4f 2617 " uint27_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2618 " } compact;\n"
2619 " struct {\n"
2620 " uint32_t id;\n"
a3ccff4f 2621 " uint64_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2622 " } extended;\n"
2623 " } v;\n"
2624 "} align(%u);\n"
2625 "\n"
2626 "struct event_header_large {\n"
2627 " enum : uint16_t { compact = 0 ... 65534, extended = 65535 } id;\n"
2628 " variant <id> {\n"
2629 " struct {\n"
a3ccff4f 2630 " uint32_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2631 " } compact;\n"
2632 " struct {\n"
2633 " uint32_t id;\n"
a3ccff4f 2634 " uint64_clock_monotonic_t timestamp;\n"
9115fbdc
MD		 2635 " } extended;\n"
2636 " } v;\n"
2637 "} align(%u);\n\n",
a90917c3
MD		 2638 lttng_alignof(uint32_t) * CHAR_BIT,
2639 lttng_alignof(uint16_t) * CHAR_BIT
9115fbdc
MD		 2640 );
2641}
2642
a3ccff4f
MD		 2643 /*
2644 * Approximation of NTP time of day to clock monotonic correlation,
2645 * taken at start of trace.
2646 * Yes, this is only an approximation. Yes, we can (and will) do better
2647 * in future versions.
5283350b
MD		 2648 * This function may return a negative offset. It may happen if the
2649 * system sets the REALTIME clock to 0 after boot.
3636085f
MJ		 2650 *
2651 * Use 64bit timespec on kernels that have it, this makes 32bit arch
2652 * y2038 compliant.
a3ccff4f
MD		 2653 */
2654static
8967b2a3 2655int64_t measure_clock_offset(void)
a3ccff4f 2656{
dcb93448 2657 uint64_t monotonic_avg, monotonic[2], realtime;
2754583e 2658 uint64_t tcf = trace_clock_freq();
dcb93448 2659 int64_t offset;
a3ccff4f 2660 unsigned long flags;
3636085f
MJ		 2661#ifdef LTTNG_KERNEL_HAS_TIMESPEC64
2662 struct timespec64 rts = { 0, 0 };
2663#else
2664 struct timespec rts = { 0, 0 };
2665#endif
a3ccff4f
MD		 2666
2667 /* Disable interrupts to increase correlation precision. */
2668 local_irq_save(flags);
2669 monotonic[0] = trace_clock_read64();
3636085f
MJ		 2670#ifdef LTTNG_KERNEL_HAS_TIMESPEC64
2671 ktime_get_real_ts64(&rts);
2672#else
216b6baa 2673 getnstimeofday(&rts);
3636085f 2674#endif
a3ccff4f
MD		 2675 monotonic[1] = trace_clock_read64();
2676 local_irq_restore(flags);
2677
dcb93448 2678 monotonic_avg = (monotonic[0] + monotonic[1]) >> 1;
2754583e
MD		 2679 realtime = (uint64_t) rts.tv_sec * tcf;
2680 if (tcf == NSEC_PER_SEC) {
2681 realtime += rts.tv_nsec;
2682 } else {
2683 uint64_t n = rts.tv_nsec * tcf;
2684
2685 do_div(n, NSEC_PER_SEC);
2686 realtime += n;
2687 }
dcb93448 2688 offset = (int64_t) realtime - monotonic_avg;
a3ccff4f
MD		 2689 return offset;
2690}
2691
3eb95be4
JR		 2692static
2693int print_escaped_ctf_string(struct lttng_session *session, const char *string)
2694{
0f3eaad4 2695 int ret = 0;
3eb95be4
JR		 2696 size_t i;
2697 char cur;
2698
2699 i = 0;
2700 cur = string[i];
2701 while (cur != '\0') {
2702 switch (cur) {
2703 case '\n':
2704 ret = lttng_metadata_printf(session, "%s", "\\n");
2705 break;
2706 case '\\':
2707 case '"':
2708 ret = lttng_metadata_printf(session, "%c", '\\');
2709 if (ret)
2710 goto error;
2711 /* We still print the current char */
2712 /* Fallthrough */
2713 default:
2714 ret = lttng_metadata_printf(session, "%c", cur);
2715 break;
2716 }
2717
2718 if (ret)
2719 goto error;
2720
2721 cur = string[++i];
2722 }
2723error:
2724 return ret;
2725}
2726
2727static
1c88f269
JR		 2728int print_metadata_escaped_field(struct lttng_session *session, const char *field,
2729 const char *field_value)
3eb95be4
JR		 2730{
2731 int ret;
2732
1c88f269 2733 ret = lttng_metadata_printf(session, " %s = \"", field);
3eb95be4
JR		 2734 if (ret)
2735 goto error;
2736
1c88f269 2737 ret = print_escaped_ctf_string(session, field_value);
3eb95be4
JR		 2738 if (ret)
2739 goto error;
2740
2741 ret = lttng_metadata_printf(session, "\";\n");
2742
2743error:
2744 return ret;
2745}
2746
c099397a
MD		 2747/*
2748 * Output metadata into this session's metadata buffers.
d83004aa 2749 * Must be called with sessions_mutex held.
c099397a
MD		 2750 */
2751static
a90917c3 2752int _lttng_session_metadata_statedump(struct lttng_session *session)
c099397a 2753{
30bdb6e4 2754 unsigned char *uuid_c = session->uuid.b;
a82c63f1 2755 unsigned char uuid_s[37], clock_uuid_s[BOOT_ID_LEN];
c88f762e 2756 const char *product_uuid;
a90917c3
MD		 2757 struct lttng_channel *chan;
2758 struct lttng_event *event;
c099397a
MD		 2759 int ret = 0;
2760
585e5dcc 2761 if (!LTTNG_READ_ONCE(session->active))
c099397a 2762 return 0;
8b97fd42
MD		 2763
2764 lttng_metadata_begin(session);
2765
c099397a
MD		 2766 if (session->metadata_dumped)
2767 goto skip_session;
c099397a 2768
d793d5e1 2769 snprintf(uuid_s, sizeof(uuid_s),
30bdb6e4
MD		 2770 "%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
2771 uuid_c[0], uuid_c[1], uuid_c[2], uuid_c[3],
2772 uuid_c[4], uuid_c[5], uuid_c[6], uuid_c[7],
2773 uuid_c[8], uuid_c[9], uuid_c[10], uuid_c[11],
2774 uuid_c[12], uuid_c[13], uuid_c[14], uuid_c[15]);
d793d5e1
MD		 2775
2776 ret = lttng_metadata_printf(session,
9115fbdc
MD		 2777 "typealias integer { size = 8; align = %u; signed = false; } := uint8_t;\n"
2778 "typealias integer { size = 16; align = %u; signed = false; } := uint16_t;\n"
2779 "typealias integer { size = 32; align = %u; signed = false; } := uint32_t;\n"
2780 "typealias integer { size = 64; align = %u; signed = false; } := uint64_t;\n"
a9afe705 2781 "typealias integer { size = %u; align = %u; signed = false; } := unsigned long;\n"
9115fbdc
MD		 2782 "typealias integer { size = 5; align = 1; signed = false; } := uint5_t;\n"
2783 "typealias integer { size = 27; align = 1; signed = false; } := uint27_t;\n"
d793d5e1
MD		 2784 "\n"
2785 "trace {\n"
2786 " major = %u;\n"
2787 " minor = %u;\n"
30bdb6e4 2788 " uuid = \"%s\";\n"
d793d5e1
MD		 2789 " byte_order = %s;\n"
2790 " packet.header := struct {\n"
2791 " uint32_t magic;\n"
1ec3f75a 2792 " uint8_t uuid[16];\n"
d793d5e1 2793 " uint32_t stream_id;\n"
5594698f 2794 " uint64_t stream_instance_id;\n"
0eb25f58 2795 " };\n"
d793d5e1 2796 "};\n\n",
a90917c3
MD		 2797 lttng_alignof(uint8_t) * CHAR_BIT,
2798 lttng_alignof(uint16_t) * CHAR_BIT,
2799 lttng_alignof(uint32_t) * CHAR_BIT,
2800 lttng_alignof(uint64_t) * CHAR_BIT,
a9afe705
MD		 2801 sizeof(unsigned long) * CHAR_BIT,
2802 lttng_alignof(unsigned long) * CHAR_BIT,
c6c9e10f
MD		 2803 CTF_SPEC_MAJOR,
2804 CTF_SPEC_MINOR,
d793d5e1 2805 uuid_s,
5214fa50 2806#if __BYTE_ORDER == __BIG_ENDIAN
d793d5e1
MD		 2807 "be"
2808#else
2809 "le"
2810#endif
2811 );
2812 if (ret)
2813 goto end;
2814
99dc9597
MD		 2815 ret = lttng_metadata_printf(session,
2816 "env {\n"
a6058143 2817 " hostname = \"%s\";\n"
c6c9e10f 2818 " domain = \"kernel\";\n"
99dc9597 2819 " sysname = \"%s\";\n"
c6c9e10f
MD		 2820 " kernel_release = \"%s\";\n"
2821 " kernel_version = \"%s\";\n"
2822 " tracer_name = \"lttng-modules\";\n"
2823 " tracer_major = %d;\n"
2824 " tracer_minor = %d;\n"
2825 " tracer_patchlevel = %d;\n"
3eb95be4 2826 " trace_buffering_scheme = \"global\";\n",
3d0d43db 2827 current->nsproxy->uts_ns->name.nodename,
99dc9597
MD		 2828 utsname()->sysname,
2829 utsname()->release,
c6c9e10f
MD		 2830 utsname()->version,
2831 LTTNG_MODULES_MAJOR_VERSION,
2832 LTTNG_MODULES_MINOR_VERSION,
2833 LTTNG_MODULES_PATCHLEVEL_VERSION
99dc9597
MD		 2834 );
2835 if (ret)
2836 goto end;
2837
1c88f269
JR		 2838 ret = print_metadata_escaped_field(session, "trace_name", session->name);
2839 if (ret)
2840 goto end;
2841 ret = print_metadata_escaped_field(session, "trace_creation_datetime",
2842 session->creation_time);
3eb95be4
JR		 2843 if (ret)
2844 goto end;
2845
c88f762e
GB		 2846 /* Add the product UUID to the 'env' section */
2847 product_uuid = dmi_get_system_info(DMI_PRODUCT_UUID);
2848 if (product_uuid) {
2849 ret = lttng_metadata_printf(session,
2850 " product_uuid = \"%s\";\n",
2851 product_uuid
2852 );
2853 if (ret)
2854 goto end;
2855 }
2856
2857 /* Close the 'env' section */
3eb95be4
JR		 2858 ret = lttng_metadata_printf(session, "};\n\n");
2859 if (ret)
2860 goto end;
2861
a3ccff4f
MD		 2862 ret = lttng_metadata_printf(session,
2863 "clock {\n"
2754583e
MD		 2864 " name = \"%s\";\n",
2865 trace_clock_name()
a82c63f1
MD		 2866 );
2867 if (ret)
2868 goto end;
2869
2870 if (!trace_clock_uuid(clock_uuid_s)) {
2871 ret = lttng_metadata_printf(session,
7c27cb17 2872 " uuid = \"%s\";\n",
a82c63f1
MD		 2873 clock_uuid_s
2874 );
2875 if (ret)
2876 goto end;
2877 }
2878
2879 ret = lttng_metadata_printf(session,
2754583e 2880 " description = \"%s\";\n"
a3ccff4f
MD		 2881 " freq = %llu; /* Frequency, in Hz */\n"
2882 " /* clock value offset from Epoch is: offset * (1/freq) */\n"
8967b2a3 2883 " offset = %lld;\n"
a3ccff4f 2884 "};\n\n",
2754583e 2885 trace_clock_description(),
a3ccff4f 2886 (unsigned long long) trace_clock_freq(),
8967b2a3 2887 (long long) measure_clock_offset()
a3ccff4f
MD		 2888 );
2889 if (ret)
2890 goto end;
2891
2892 ret = lttng_metadata_printf(session,
2893 "typealias integer {\n"
2894 " size = 27; align = 1; signed = false;\n"
2754583e 2895 " map = clock.%s.value;\n"
a3ccff4f
MD		 2896 "} := uint27_clock_monotonic_t;\n"
2897 "\n"
2898 "typealias integer {\n"
2899 " size = 32; align = %u; signed = false;\n"
2754583e 2900 " map = clock.%s.value;\n"
a3ccff4f
MD		 2901 "} := uint32_clock_monotonic_t;\n"
2902 "\n"
2903 "typealias integer {\n"
2904 " size = 64; align = %u; signed = false;\n"
2754583e 2905 " map = clock.%s.value;\n"
a3ccff4f 2906 "} := uint64_clock_monotonic_t;\n\n",
2754583e 2907 trace_clock_name(),
a3ccff4f 2908 lttng_alignof(uint32_t) * CHAR_BIT,
2754583e
MD		 2909 trace_clock_name(),
2910 lttng_alignof(uint64_t) * CHAR_BIT,
2911 trace_clock_name()
a3ccff4f
MD		 2912 );
2913 if (ret)
2914 goto end;
2915
a90917c3 2916 ret = _lttng_stream_packet_context_declare(session);
9115fbdc
MD		 2917 if (ret)
2918 goto end;
2919
a90917c3 2920 ret = _lttng_event_header_declare(session);
9115fbdc
MD		 2921 if (ret)
2922 goto end;
2923
c099397a
MD		 2924skip_session:
2925 list_for_each_entry(chan, &session->chan, list) {
a90917c3 2926 ret = _lttng_channel_metadata_statedump(session, chan);
c099397a
MD		 2927 if (ret)
2928 goto end;
2929 }
2930
2931 list_for_each_entry(event, &session->events, list) {
a90917c3 2932 ret = _lttng_event_metadata_statedump(session, event->chan, event);
c099397a
MD		 2933 if (ret)
2934 goto end;
2935 }
2936 session->metadata_dumped = 1;
2937end:
8b97fd42 2938 lttng_metadata_end(session);
c099397a
MD		 2939 return ret;
2940}
2941
c0e31d2e 2942/**
a90917c3 2943 * lttng_transport_register - LTT transport registration
c0e31d2e
MD		 2944 * @transport: transport structure
2945 *
2946 * Registers a transport which can be used as output to extract the data out of
2947 * LTTng. The module calling this registration function must ensure that no
2948 * trap-inducing code will be executed by the transport functions. E.g.
263b6c88 2949 * vmalloc_sync_mappings() must be called between a vmalloc and the moment the memory
c0e31d2e 2950 * is made visible to the transport function. This registration acts as a
263b6c88 2951 * vmalloc_sync_mappings. Therefore, only if the module allocates virtual memory
c0e31d2e
MD		 2952 * after its registration must it synchronize the TLBs.
2953 */
a90917c3 2954void lttng_transport_register(struct lttng_transport *transport)
c0e31d2e
MD		 2955{
2956 /*
2957 * Make sure no page fault can be triggered by the module about to be
2958 * registered. We deal with this here so we don't have to call
263b6c88 2959 * vmalloc_sync_mappings() in each module's init.
c0e31d2e 2960 */
263b6c88 2961 wrapper_vmalloc_sync_mappings();
c0e31d2e
MD		 2962
2963 mutex_lock(&sessions_mutex);
a90917c3 2964 list_add_tail(&transport->node, &lttng_transport_list);
c0e31d2e
MD		 2965 mutex_unlock(&sessions_mutex);
2966}
a90917c3 2967EXPORT_SYMBOL_GPL(lttng_transport_register);
c0e31d2e
MD		 2968
2969/**
a90917c3 2970 * lttng_transport_unregister - LTT transport unregistration
c0e31d2e
MD		 2971 * @transport: transport structure
2972 */
a90917c3 2973void lttng_transport_unregister(struct lttng_transport *transport)
c0e31d2e
MD		 2974{
2975 mutex_lock(&sessions_mutex);
2976 list_del(&transport->node);
2977 mutex_unlock(&sessions_mutex);
2978}
a90917c3 2979EXPORT_SYMBOL_GPL(lttng_transport_unregister);
c0e31d2e 2980
894ce5dc 2981#if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0))
1e367326
MD		 2982
2983enum cpuhp_state lttng_hp_prepare;
2984enum cpuhp_state lttng_hp_online;
2985
2986static int lttng_hotplug_prepare(unsigned int cpu, struct hlist_node *node)
2987{
2988 struct lttng_cpuhp_node *lttng_node;
2989
2990 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
2991 switch (lttng_node->component) {
2992 case LTTNG_RING_BUFFER_FRONTEND:
2993 return 0;
2994 case LTTNG_RING_BUFFER_BACKEND:
2995 return lttng_cpuhp_rb_backend_prepare(cpu, lttng_node);
2996 case LTTNG_RING_BUFFER_ITER:
2997 return 0;
2998 case LTTNG_CONTEXT_PERF_COUNTERS:
2999 return 0;
3000 default:
3001 return -EINVAL;
3002 }
3003}
3004
3005static int lttng_hotplug_dead(unsigned int cpu, struct hlist_node *node)
3006{
3007 struct lttng_cpuhp_node *lttng_node;
3008
3009 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
3010 switch (lttng_node->component) {
3011 case LTTNG_RING_BUFFER_FRONTEND:
3012 return lttng_cpuhp_rb_frontend_dead(cpu, lttng_node);
3013 case LTTNG_RING_BUFFER_BACKEND:
3014 return 0;
3015 case LTTNG_RING_BUFFER_ITER:
3016 return 0;
3017 case LTTNG_CONTEXT_PERF_COUNTERS:
3018 return lttng_cpuhp_perf_counter_dead(cpu, lttng_node);
3019 default:
3020 return -EINVAL;
3021 }
3022}
3023
3024static int lttng_hotplug_online(unsigned int cpu, struct hlist_node *node)
3025{
3026 struct lttng_cpuhp_node *lttng_node;
3027
3028 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
3029 switch (lttng_node->component) {
3030 case LTTNG_RING_BUFFER_FRONTEND:
3031 return lttng_cpuhp_rb_frontend_online(cpu, lttng_node);
3032 case LTTNG_RING_BUFFER_BACKEND:
3033 return 0;
3034 case LTTNG_RING_BUFFER_ITER:
3035 return lttng_cpuhp_rb_iter_online(cpu, lttng_node);
3036 case LTTNG_CONTEXT_PERF_COUNTERS:
3037 return lttng_cpuhp_perf_counter_online(cpu, lttng_node);
3038 default:
3039 return -EINVAL;
3040 }
3041}
3042
3043static int lttng_hotplug_offline(unsigned int cpu, struct hlist_node *node)
3044{
3045 struct lttng_cpuhp_node *lttng_node;
3046
3047 lttng_node = container_of(node, struct lttng_cpuhp_node, node);
3048 switch (lttng_node->component) {
3049 case LTTNG_RING_BUFFER_FRONTEND:
3050 return lttng_cpuhp_rb_frontend_offline(cpu, lttng_node);
3051 case LTTNG_RING_BUFFER_BACKEND:
3052 return 0;
3053 case LTTNG_RING_BUFFER_ITER:
3054 return 0;
3055 case LTTNG_CONTEXT_PERF_COUNTERS:
3056 return 0;
3057 default:
3058 return -EINVAL;
3059 }
3060}
3061
3062static int __init lttng_init_cpu_hotplug(void)
3063{
3064 int ret;
3065
3066 ret = cpuhp_setup_state_multi(CPUHP_BP_PREPARE_DYN, "lttng:prepare",
3067 lttng_hotplug_prepare,
3068 lttng_hotplug_dead);
3069 if (ret < 0) {
3070 return ret;
3071 }
3072 lttng_hp_prepare = ret;
3073 lttng_rb_set_hp_prepare(ret);
3074
3075 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "lttng:online",
3076 lttng_hotplug_online,
3077 lttng_hotplug_offline);
3078 if (ret < 0) {
3079 cpuhp_remove_multi_state(lttng_hp_prepare);
3080 lttng_hp_prepare = 0;
3081 return ret;
3082 }
3083 lttng_hp_online = ret;
3084 lttng_rb_set_hp_online(ret);
3085
3086 return 0;
3087}
3088
3089static void __exit lttng_exit_cpu_hotplug(void)
3090{
3091 lttng_rb_set_hp_online(0);
3092 cpuhp_remove_multi_state(lttng_hp_online);
3093 lttng_rb_set_hp_prepare(0);
3094 cpuhp_remove_multi_state(lttng_hp_prepare);
3095}
3096
1ee63d8d 3097#else /* #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
1e367326
MD		 3098static int lttng_init_cpu_hotplug(void)
3099{
3100 return 0;
3101}
3102static void lttng_exit_cpu_hotplug(void)
3103{
3104}
1ee63d8d 3105#endif /* #else #if (LINUX_VERSION_CODE >= KERNEL_VERSION(4,10,0)) */
1e367326
MD		 3106
3107
a90917c3 3108static int __init lttng_events_init(void)
4e3c1b9b 3109{
1c25284c
MD		 3110 int ret;
3111
453b2495
JD		 3112 ret = wrapper_lttng_fixup_sig(THIS_MODULE);
3113 if (ret)
3114 return ret;
389d7070 3115 ret = wrapper_get_pfnblock_flags_mask_init();
36561775
MD		 3116 if (ret)
3117 return ret;
3118 ret = wrapper_get_pageblock_flags_mask_init();
114667d5
MD		 3119 if (ret)
3120 return ret;
3121 ret = lttng_probes_init();
389d7070
MD		 3122 if (ret)
3123 return ret;
07dfc1d0 3124 ret = lttng_context_init();
20591cf7
MD		 3125 if (ret)
3126 return ret;
07dfc1d0
MD		 3127 ret = lttng_tracepoint_init();
3128 if (ret)
3129 goto error_tp;
a90917c3 3130 event_cache = KMEM_CACHE(lttng_event, 0);
20591cf7
MD		 3131 if (!event_cache) {
3132 ret = -ENOMEM;
3133 goto error_kmem;
3134 }
80996790 3135 ret = lttng_abi_init();
02119ee5
MD		 3136 if (ret)
3137 goto error_abi;
0c956676
MD		 3138 ret = lttng_logger_init();
3139 if (ret)
3140 goto error_logger;
1e367326
MD		 3141 ret = lttng_init_cpu_hotplug();
3142 if (ret)
3143 goto error_hotplug;
101215b7 3144 printk(KERN_NOTICE "LTTng: Loaded modules v%s.%s.%s%s (%s)%s%s\n",
489de24b
MJ		 3145 __stringify(LTTNG_MODULES_MAJOR_VERSION),
3146 __stringify(LTTNG_MODULES_MINOR_VERSION),
3147 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
3148 LTTNG_MODULES_EXTRAVERSION,
101215b7
MJ		 3149 LTTNG_VERSION_NAME,
3150#ifdef LTTNG_EXTRA_VERSION_GIT
3151 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
3152#else
3153 "",
3154#endif
3155#ifdef LTTNG_EXTRA_VERSION_NAME
3156 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
3157#else
3158 "");
3159#endif
4e3c1b9b 3160 return 0;
0c956676 3161
1e367326
MD		 3162error_hotplug:
3163 lttng_logger_exit();
0c956676
MD		 3164error_logger:
3165 lttng_abi_exit();
02119ee5 3166error_abi:
1c25284c 3167 kmem_cache_destroy(event_cache);
20591cf7
MD		 3168error_kmem:
3169 lttng_tracepoint_exit();
07dfc1d0
MD		 3170error_tp:
3171 lttng_context_exit();
101215b7 3172 printk(KERN_NOTICE "LTTng: Failed to load modules v%s.%s.%s%s (%s)%s%s\n",
489de24b
MJ		 3173 __stringify(LTTNG_MODULES_MAJOR_VERSION),
3174 __stringify(LTTNG_MODULES_MINOR_VERSION),
3175 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
3176 LTTNG_MODULES_EXTRAVERSION,
101215b7
MJ		 3177 LTTNG_VERSION_NAME,
3178#ifdef LTTNG_EXTRA_VERSION_GIT
3179 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
3180#else
3181 "",
3182#endif
3183#ifdef LTTNG_EXTRA_VERSION_NAME
3184 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
3185#else
3186 "");
3187#endif
1c25284c 3188 return ret;
4e3c1b9b
MD		 3189}
3190
a90917c3 3191module_init(lttng_events_init);
11b5a3c2 3192
a90917c3 3193static void __exit lttng_events_exit(void)
4e3c1b9b 3194{
a90917c3 3195 struct lttng_session *session, *tmpsession;
92e94819 3196
1e367326 3197 lttng_exit_cpu_hotplug();
0c956676 3198 lttng_logger_exit();
80996790 3199 lttng_abi_exit();
92e94819 3200 list_for_each_entry_safe(session, tmpsession, &sessions, list)
a90917c3 3201 lttng_session_destroy(session);
11b5a3c2 3202 kmem_cache_destroy(event_cache);
20591cf7 3203 lttng_tracepoint_exit();
07dfc1d0 3204 lttng_context_exit();
101215b7 3205 printk(KERN_NOTICE "LTTng: Unloaded modules v%s.%s.%s%s (%s)%s%s\n",
489de24b
MJ		 3206 __stringify(LTTNG_MODULES_MAJOR_VERSION),
3207 __stringify(LTTNG_MODULES_MINOR_VERSION),
3208 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION),
3209 LTTNG_MODULES_EXTRAVERSION,
101215b7
MJ		 3210 LTTNG_VERSION_NAME,
3211#ifdef LTTNG_EXTRA_VERSION_GIT
3212 LTTNG_EXTRA_VERSION_GIT[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_GIT,
3213#else
3214 "",
3215#endif
3216#ifdef LTTNG_EXTRA_VERSION_NAME
3217 LTTNG_EXTRA_VERSION_NAME[0] == '\0' ? "" : " - " LTTNG_EXTRA_VERSION_NAME);
3218#else
3219 "");
3220#endif
4e3c1b9b 3221}
92e94819 3222
a90917c3 3223module_exit(lttng_events_exit);
11b5a3c2 3224
7ca11e77 3225#include <generated/patches.h>
101215b7
MJ		 3226#ifdef LTTNG_EXTRA_VERSION_GIT
3227MODULE_INFO(extra_version_git, LTTNG_EXTRA_VERSION_GIT);
3228#endif
3229#ifdef LTTNG_EXTRA_VERSION_NAME
3230MODULE_INFO(extra_version_name, LTTNG_EXTRA_VERSION_NAME);
3231#endif
92e94819
MD		 3232MODULE_LICENSE("GPL and additional rights");
3233MODULE_AUTHOR("Mathieu Desnoyers <mathieu.desnoyers@efficios.com>");
1c124020 3234MODULE_DESCRIPTION("LTTng tracer");
9a9973ef
MD		 3235MODULE_VERSION(__stringify(LTTNG_MODULES_MAJOR_VERSION) "."
3236 __stringify(LTTNG_MODULES_MINOR_VERSION) "."
309370e2
MD		 3237 __stringify(LTTNG_MODULES_PATCHLEVEL_VERSION)
3238 LTTNG_MODULES_EXTRAVERSION);
LTTng 2.0/0.x modules
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