8120b6df21188ea88331bba2a7c27c883d9b410d
[lttng-tools.git] / src / bin / lttng-sessiond / ust-app.c
1 /*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18
19 #define _LGPL_SOURCE
20 #include <errno.h>
21 #include <inttypes.h>
22 #include <pthread.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26 #include <sys/stat.h>
27 #include <sys/types.h>
28 #include <unistd.h>
29 #include <urcu/compiler.h>
30 #include <lttng/ust-error.h>
31 #include <signal.h>
32
33 #include <common/common.h>
34 #include <common/sessiond-comm/sessiond-comm.h>
35
36 #include "buffer-registry.h"
37 #include "fd-limit.h"
38 #include "health-sessiond.h"
39 #include "ust-app.h"
40 #include "ust-consumer.h"
41 #include "ust-ctl.h"
42 #include "utils.h"
43 #include "session.h"
44 #include "lttng-sessiond.h"
45 #include "notification-thread-commands.h"
46 #include "rotate.h"
47
48 static
49 int ust_app_flush_app_session(struct ust_app *app, struct ust_app_session *ua_sess);
50
51 /* Next available channel key. Access under next_channel_key_lock. */
52 static uint64_t _next_channel_key;
53 static pthread_mutex_t next_channel_key_lock = PTHREAD_MUTEX_INITIALIZER;
54
55 /* Next available session ID. Access under next_session_id_lock. */
56 static uint64_t _next_session_id;
57 static pthread_mutex_t next_session_id_lock = PTHREAD_MUTEX_INITIALIZER;
58
59 /*
60 * Return the incremented value of next_channel_key.
61 */
62 static uint64_t get_next_channel_key(void)
63 {
64 uint64_t ret;
65
66 pthread_mutex_lock(&next_channel_key_lock);
67 ret = ++_next_channel_key;
68 pthread_mutex_unlock(&next_channel_key_lock);
69 return ret;
70 }
71
72 /*
73 * Return the atomically incremented value of next_session_id.
74 */
75 static uint64_t get_next_session_id(void)
76 {
77 uint64_t ret;
78
79 pthread_mutex_lock(&next_session_id_lock);
80 ret = ++_next_session_id;
81 pthread_mutex_unlock(&next_session_id_lock);
82 return ret;
83 }
84
85 static void copy_channel_attr_to_ustctl(
86 struct ustctl_consumer_channel_attr *attr,
87 struct lttng_ust_channel_attr *uattr)
88 {
89 /* Copy event attributes since the layout is different. */
90 attr->subbuf_size = uattr->subbuf_size;
91 attr->num_subbuf = uattr->num_subbuf;
92 attr->overwrite = uattr->overwrite;
93 attr->switch_timer_interval = uattr->switch_timer_interval;
94 attr->read_timer_interval = uattr->read_timer_interval;
95 attr->output = uattr->output;
96 attr->blocking_timeout = uattr->u.s.blocking_timeout;
97 }
98
99 /*
100 * Match function for the hash table lookup.
101 *
102 * It matches an ust app event based on three attributes which are the event
103 * name, the filter bytecode and the loglevel.
104 */
105 static int ht_match_ust_app_event(struct cds_lfht_node *node, const void *_key)
106 {
107 struct ust_app_event *event;
108 const struct ust_app_ht_key *key;
109 int ev_loglevel_value;
110
111 assert(node);
112 assert(_key);
113
114 event = caa_container_of(node, struct ust_app_event, node.node);
115 key = _key;
116 ev_loglevel_value = event->attr.loglevel;
117
118 /* Match the 4 elements of the key: name, filter, loglevel, exclusions */
119
120 /* Event name */
121 if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) {
122 goto no_match;
123 }
124
125 /* Event loglevel. */
126 if (ev_loglevel_value != key->loglevel_type) {
127 if (event->attr.loglevel_type == LTTNG_UST_LOGLEVEL_ALL
128 && key->loglevel_type == 0 &&
129 ev_loglevel_value == -1) {
130 /*
131 * Match is accepted. This is because on event creation, the
132 * loglevel is set to -1 if the event loglevel type is ALL so 0 and
133 * -1 are accepted for this loglevel type since 0 is the one set by
134 * the API when receiving an enable event.
135 */
136 } else {
137 goto no_match;
138 }
139 }
140
141 /* One of the filters is NULL, fail. */
142 if ((key->filter && !event->filter) || (!key->filter && event->filter)) {
143 goto no_match;
144 }
145
146 if (key->filter && event->filter) {
147 /* Both filters exists, check length followed by the bytecode. */
148 if (event->filter->len != key->filter->len ||
149 memcmp(event->filter->data, key->filter->data,
150 event->filter->len) != 0) {
151 goto no_match;
152 }
153 }
154
155 /* One of the exclusions is NULL, fail. */
156 if ((key->exclusion && !event->exclusion) || (!key->exclusion && event->exclusion)) {
157 goto no_match;
158 }
159
160 if (key->exclusion && event->exclusion) {
161 /* Both exclusions exists, check count followed by the names. */
162 if (event->exclusion->count != key->exclusion->count ||
163 memcmp(event->exclusion->names, key->exclusion->names,
164 event->exclusion->count * LTTNG_UST_SYM_NAME_LEN) != 0) {
165 goto no_match;
166 }
167 }
168
169
170 /* Match. */
171 return 1;
172
173 no_match:
174 return 0;
175 }
176
177 /*
178 * Unique add of an ust app event in the given ht. This uses the custom
179 * ht_match_ust_app_event match function and the event name as hash.
180 */
181 static void add_unique_ust_app_event(struct ust_app_channel *ua_chan,
182 struct ust_app_event *event)
183 {
184 struct cds_lfht_node *node_ptr;
185 struct ust_app_ht_key key;
186 struct lttng_ht *ht;
187
188 assert(ua_chan);
189 assert(ua_chan->events);
190 assert(event);
191
192 ht = ua_chan->events;
193 key.name = event->attr.name;
194 key.filter = event->filter;
195 key.loglevel_type = event->attr.loglevel;
196 key.exclusion = event->exclusion;
197
198 node_ptr = cds_lfht_add_unique(ht->ht,
199 ht->hash_fct(event->node.key, lttng_ht_seed),
200 ht_match_ust_app_event, &key, &event->node.node);
201 assert(node_ptr == &event->node.node);
202 }
203
204 /*
205 * Close the notify socket from the given RCU head object. This MUST be called
206 * through a call_rcu().
207 */
208 static void close_notify_sock_rcu(struct rcu_head *head)
209 {
210 int ret;
211 struct ust_app_notify_sock_obj *obj =
212 caa_container_of(head, struct ust_app_notify_sock_obj, head);
213
214 /* Must have a valid fd here. */
215 assert(obj->fd >= 0);
216
217 ret = close(obj->fd);
218 if (ret) {
219 ERR("close notify sock %d RCU", obj->fd);
220 }
221 lttng_fd_put(LTTNG_FD_APPS, 1);
222
223 free(obj);
224 }
225
226 /*
227 * Return the session registry according to the buffer type of the given
228 * session.
229 *
230 * A registry per UID object MUST exists before calling this function or else
231 * it assert() if not found. RCU read side lock must be acquired.
232 */
233 static struct ust_registry_session *get_session_registry(
234 struct ust_app_session *ua_sess)
235 {
236 struct ust_registry_session *registry = NULL;
237
238 assert(ua_sess);
239
240 switch (ua_sess->buffer_type) {
241 case LTTNG_BUFFER_PER_PID:
242 {
243 struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
244 if (!reg_pid) {
245 goto error;
246 }
247 registry = reg_pid->registry->reg.ust;
248 break;
249 }
250 case LTTNG_BUFFER_PER_UID:
251 {
252 struct buffer_reg_uid *reg_uid = buffer_reg_uid_find(
253 ua_sess->tracing_id, ua_sess->bits_per_long, ua_sess->uid);
254 if (!reg_uid) {
255 goto error;
256 }
257 registry = reg_uid->registry->reg.ust;
258 break;
259 }
260 default:
261 assert(0);
262 };
263
264 error:
265 return registry;
266 }
267
268 /*
269 * Delete ust context safely. RCU read lock must be held before calling
270 * this function.
271 */
272 static
273 void delete_ust_app_ctx(int sock, struct ust_app_ctx *ua_ctx,
274 struct ust_app *app)
275 {
276 int ret;
277
278 assert(ua_ctx);
279
280 if (ua_ctx->obj) {
281 pthread_mutex_lock(&app->sock_lock);
282 ret = ustctl_release_object(sock, ua_ctx->obj);
283 pthread_mutex_unlock(&app->sock_lock);
284 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
285 ERR("UST app sock %d release ctx obj handle %d failed with ret %d",
286 sock, ua_ctx->obj->handle, ret);
287 }
288 free(ua_ctx->obj);
289 }
290 free(ua_ctx);
291 }
292
293 /*
294 * Delete ust app event safely. RCU read lock must be held before calling
295 * this function.
296 */
297 static
298 void delete_ust_app_event(int sock, struct ust_app_event *ua_event,
299 struct ust_app *app)
300 {
301 int ret;
302
303 assert(ua_event);
304
305 free(ua_event->filter);
306 if (ua_event->exclusion != NULL)
307 free(ua_event->exclusion);
308 if (ua_event->obj != NULL) {
309 pthread_mutex_lock(&app->sock_lock);
310 ret = ustctl_release_object(sock, ua_event->obj);
311 pthread_mutex_unlock(&app->sock_lock);
312 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
313 ERR("UST app sock %d release event obj failed with ret %d",
314 sock, ret);
315 }
316 free(ua_event->obj);
317 }
318 free(ua_event);
319 }
320
321 /*
322 * Release ust data object of the given stream.
323 *
324 * Return 0 on success or else a negative value.
325 */
326 static int release_ust_app_stream(int sock, struct ust_app_stream *stream,
327 struct ust_app *app)
328 {
329 int ret = 0;
330
331 assert(stream);
332
333 if (stream->obj) {
334 pthread_mutex_lock(&app->sock_lock);
335 ret = ustctl_release_object(sock, stream->obj);
336 pthread_mutex_unlock(&app->sock_lock);
337 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
338 ERR("UST app sock %d release stream obj failed with ret %d",
339 sock, ret);
340 }
341 lttng_fd_put(LTTNG_FD_APPS, 2);
342 free(stream->obj);
343 }
344
345 return ret;
346 }
347
348 /*
349 * Delete ust app stream safely. RCU read lock must be held before calling
350 * this function.
351 */
352 static
353 void delete_ust_app_stream(int sock, struct ust_app_stream *stream,
354 struct ust_app *app)
355 {
356 assert(stream);
357
358 (void) release_ust_app_stream(sock, stream, app);
359 free(stream);
360 }
361
362 /*
363 * We need to execute ht_destroy outside of RCU read-side critical
364 * section and outside of call_rcu thread, so we postpone its execution
365 * using ht_cleanup_push. It is simpler than to change the semantic of
366 * the many callers of delete_ust_app_session().
367 */
368 static
369 void delete_ust_app_channel_rcu(struct rcu_head *head)
370 {
371 struct ust_app_channel *ua_chan =
372 caa_container_of(head, struct ust_app_channel, rcu_head);
373
374 ht_cleanup_push(ua_chan->ctx);
375 ht_cleanup_push(ua_chan->events);
376 free(ua_chan);
377 }
378
379 /*
380 * Extract the lost packet or discarded events counter when the channel is
381 * being deleted and store the value in the parent channel so we can
382 * access it from lttng list and at stop/destroy.
383 *
384 * The session list lock must be held by the caller.
385 */
386 static
387 void save_per_pid_lost_discarded_counters(struct ust_app_channel *ua_chan)
388 {
389 uint64_t discarded = 0, lost = 0;
390 struct ltt_session *session;
391 struct ltt_ust_channel *uchan;
392
393 if (ua_chan->attr.type != LTTNG_UST_CHAN_PER_CPU) {
394 return;
395 }
396
397 rcu_read_lock();
398 session = session_find_by_id(ua_chan->session->tracing_id);
399 if (!session || !session->ust_session) {
400 /*
401 * Not finding the session is not an error because there are
402 * multiple ways the channels can be torn down.
403 *
404 * 1) The session daemon can initiate the destruction of the
405 * ust app session after receiving a destroy command or
406 * during its shutdown/teardown.
407 * 2) The application, since we are in per-pid tracing, is
408 * unregistering and tearing down its ust app session.
409 *
410 * Both paths are protected by the session list lock which
411 * ensures that the accounting of lost packets and discarded
412 * events is done exactly once. The session is then unpublished
413 * from the session list, resulting in this condition.
414 */
415 goto end;
416 }
417
418 if (ua_chan->attr.overwrite) {
419 consumer_get_lost_packets(ua_chan->session->tracing_id,
420 ua_chan->key, session->ust_session->consumer,
421 &lost);
422 } else {
423 consumer_get_discarded_events(ua_chan->session->tracing_id,
424 ua_chan->key, session->ust_session->consumer,
425 &discarded);
426 }
427 uchan = trace_ust_find_channel_by_name(
428 session->ust_session->domain_global.channels,
429 ua_chan->name);
430 if (!uchan) {
431 ERR("Missing UST channel to store discarded counters");
432 goto end;
433 }
434
435 uchan->per_pid_closed_app_discarded += discarded;
436 uchan->per_pid_closed_app_lost += lost;
437
438 end:
439 rcu_read_unlock();
440 }
441
442 /*
443 * Delete ust app channel safely. RCU read lock must be held before calling
444 * this function.
445 *
446 * The session list lock must be held by the caller.
447 */
448 static
449 void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan,
450 struct ust_app *app)
451 {
452 int ret;
453 struct lttng_ht_iter iter;
454 struct ust_app_event *ua_event;
455 struct ust_app_ctx *ua_ctx;
456 struct ust_app_stream *stream, *stmp;
457 struct ust_registry_session *registry;
458
459 assert(ua_chan);
460
461 DBG3("UST app deleting channel %s", ua_chan->name);
462
463 /* Wipe stream */
464 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
465 cds_list_del(&stream->list);
466 delete_ust_app_stream(sock, stream, app);
467 }
468
469 /* Wipe context */
470 cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter.iter, ua_ctx, node.node) {
471 cds_list_del(&ua_ctx->list);
472 ret = lttng_ht_del(ua_chan->ctx, &iter);
473 assert(!ret);
474 delete_ust_app_ctx(sock, ua_ctx, app);
475 }
476
477 /* Wipe events */
478 cds_lfht_for_each_entry(ua_chan->events->ht, &iter.iter, ua_event,
479 node.node) {
480 ret = lttng_ht_del(ua_chan->events, &iter);
481 assert(!ret);
482 delete_ust_app_event(sock, ua_event, app);
483 }
484
485 if (ua_chan->session->buffer_type == LTTNG_BUFFER_PER_PID) {
486 /* Wipe and free registry from session registry. */
487 registry = get_session_registry(ua_chan->session);
488 if (registry) {
489 ust_registry_channel_del_free(registry, ua_chan->key,
490 true);
491 }
492 save_per_pid_lost_discarded_counters(ua_chan);
493 }
494
495 if (ua_chan->obj != NULL) {
496 /* Remove channel from application UST object descriptor. */
497 iter.iter.node = &ua_chan->ust_objd_node.node;
498 ret = lttng_ht_del(app->ust_objd, &iter);
499 assert(!ret);
500 pthread_mutex_lock(&app->sock_lock);
501 ret = ustctl_release_object(sock, ua_chan->obj);
502 pthread_mutex_unlock(&app->sock_lock);
503 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
504 ERR("UST app sock %d release channel obj failed with ret %d",
505 sock, ret);
506 }
507 lttng_fd_put(LTTNG_FD_APPS, 1);
508 free(ua_chan->obj);
509 }
510 call_rcu(&ua_chan->rcu_head, delete_ust_app_channel_rcu);
511 }
512
513 int ust_app_register_done(struct ust_app *app)
514 {
515 int ret;
516
517 pthread_mutex_lock(&app->sock_lock);
518 ret = ustctl_register_done(app->sock);
519 pthread_mutex_unlock(&app->sock_lock);
520 return ret;
521 }
522
523 int ust_app_release_object(struct ust_app *app, struct lttng_ust_object_data *data)
524 {
525 int ret, sock;
526
527 if (app) {
528 pthread_mutex_lock(&app->sock_lock);
529 sock = app->sock;
530 } else {
531 sock = -1;
532 }
533 ret = ustctl_release_object(sock, data);
534 if (app) {
535 pthread_mutex_unlock(&app->sock_lock);
536 }
537 return ret;
538 }
539
540 /*
541 * Push metadata to consumer socket.
542 *
543 * RCU read-side lock must be held to guarantee existance of socket.
544 * Must be called with the ust app session lock held.
545 * Must be called with the registry lock held.
546 *
547 * On success, return the len of metadata pushed or else a negative value.
548 * Returning a -EPIPE return value means we could not send the metadata,
549 * but it can be caused by recoverable errors (e.g. the application has
550 * terminated concurrently).
551 */
552 ssize_t ust_app_push_metadata(struct ust_registry_session *registry,
553 struct consumer_socket *socket, int send_zero_data)
554 {
555 int ret;
556 char *metadata_str = NULL;
557 size_t len, offset, new_metadata_len_sent;
558 ssize_t ret_val;
559 uint64_t metadata_key, metadata_version;
560
561 assert(registry);
562 assert(socket);
563
564 metadata_key = registry->metadata_key;
565
566 /*
567 * Means that no metadata was assigned to the session. This can
568 * happens if no start has been done previously.
569 */
570 if (!metadata_key) {
571 return 0;
572 }
573
574 offset = registry->metadata_len_sent;
575 len = registry->metadata_len - registry->metadata_len_sent;
576 new_metadata_len_sent = registry->metadata_len;
577 metadata_version = registry->metadata_version;
578 if (len == 0) {
579 DBG3("No metadata to push for metadata key %" PRIu64,
580 registry->metadata_key);
581 ret_val = len;
582 if (send_zero_data) {
583 DBG("No metadata to push");
584 goto push_data;
585 }
586 goto end;
587 }
588
589 /* Allocate only what we have to send. */
590 metadata_str = zmalloc(len);
591 if (!metadata_str) {
592 PERROR("zmalloc ust app metadata string");
593 ret_val = -ENOMEM;
594 goto error;
595 }
596 /* Copy what we haven't sent out. */
597 memcpy(metadata_str, registry->metadata + offset, len);
598
599 push_data:
600 pthread_mutex_unlock(&registry->lock);
601 /*
602 * We need to unlock the registry while we push metadata to
603 * break a circular dependency between the consumerd metadata
604 * lock and the sessiond registry lock. Indeed, pushing metadata
605 * to the consumerd awaits that it gets pushed all the way to
606 * relayd, but doing so requires grabbing the metadata lock. If
607 * a concurrent metadata request is being performed by
608 * consumerd, this can try to grab the registry lock on the
609 * sessiond while holding the metadata lock on the consumer
610 * daemon. Those push and pull schemes are performed on two
611 * different bidirectionnal communication sockets.
612 */
613 ret = consumer_push_metadata(socket, metadata_key,
614 metadata_str, len, offset, metadata_version);
615 pthread_mutex_lock(&registry->lock);
616 if (ret < 0) {
617 /*
618 * There is an acceptable race here between the registry
619 * metadata key assignment and the creation on the
620 * consumer. The session daemon can concurrently push
621 * metadata for this registry while being created on the
622 * consumer since the metadata key of the registry is
623 * assigned *before* it is setup to avoid the consumer
624 * to ask for metadata that could possibly be not found
625 * in the session daemon.
626 *
627 * The metadata will get pushed either by the session
628 * being stopped or the consumer requesting metadata if
629 * that race is triggered.
630 */
631 if (ret == -LTTCOMM_CONSUMERD_CHANNEL_FAIL) {
632 ret = 0;
633 } else {
634 ERR("Error pushing metadata to consumer");
635 }
636 ret_val = ret;
637 goto error_push;
638 } else {
639 /*
640 * Metadata may have been concurrently pushed, since
641 * we're not holding the registry lock while pushing to
642 * consumer. This is handled by the fact that we send
643 * the metadata content, size, and the offset at which
644 * that metadata belongs. This may arrive out of order
645 * on the consumer side, and the consumer is able to
646 * deal with overlapping fragments. The consumer
647 * supports overlapping fragments, which must be
648 * contiguous starting from offset 0. We keep the
649 * largest metadata_len_sent value of the concurrent
650 * send.
651 */
652 registry->metadata_len_sent =
653 max_t(size_t, registry->metadata_len_sent,
654 new_metadata_len_sent);
655 }
656 free(metadata_str);
657 return len;
658
659 end:
660 error:
661 if (ret_val) {
662 /*
663 * On error, flag the registry that the metadata is
664 * closed. We were unable to push anything and this
665 * means that either the consumer is not responding or
666 * the metadata cache has been destroyed on the
667 * consumer.
668 */
669 registry->metadata_closed = 1;
670 }
671 error_push:
672 free(metadata_str);
673 return ret_val;
674 }
675
676 /*
677 * For a given application and session, push metadata to consumer.
678 * Either sock or consumer is required : if sock is NULL, the default
679 * socket to send the metadata is retrieved from consumer, if sock
680 * is not NULL we use it to send the metadata.
681 * RCU read-side lock must be held while calling this function,
682 * therefore ensuring existance of registry. It also ensures existance
683 * of socket throughout this function.
684 *
685 * Return 0 on success else a negative error.
686 * Returning a -EPIPE return value means we could not send the metadata,
687 * but it can be caused by recoverable errors (e.g. the application has
688 * terminated concurrently).
689 */
690 static int push_metadata(struct ust_registry_session *registry,
691 struct consumer_output *consumer)
692 {
693 int ret_val;
694 ssize_t ret;
695 struct consumer_socket *socket;
696
697 assert(registry);
698 assert(consumer);
699
700 pthread_mutex_lock(&registry->lock);
701 if (registry->metadata_closed) {
702 ret_val = -EPIPE;
703 goto error;
704 }
705
706 /* Get consumer socket to use to push the metadata.*/
707 socket = consumer_find_socket_by_bitness(registry->bits_per_long,
708 consumer);
709 if (!socket) {
710 ret_val = -1;
711 goto error;
712 }
713
714 ret = ust_app_push_metadata(registry, socket, 0);
715 if (ret < 0) {
716 ret_val = ret;
717 goto error;
718 }
719 pthread_mutex_unlock(&registry->lock);
720 return 0;
721
722 error:
723 pthread_mutex_unlock(&registry->lock);
724 return ret_val;
725 }
726
727 /*
728 * Send to the consumer a close metadata command for the given session. Once
729 * done, the metadata channel is deleted and the session metadata pointer is
730 * nullified. The session lock MUST be held unless the application is
731 * in the destroy path.
732 *
733 * Return 0 on success else a negative value.
734 */
735 static int close_metadata(struct ust_registry_session *registry,
736 struct consumer_output *consumer)
737 {
738 int ret;
739 struct consumer_socket *socket;
740
741 assert(registry);
742 assert(consumer);
743
744 rcu_read_lock();
745
746 pthread_mutex_lock(&registry->lock);
747
748 if (!registry->metadata_key || registry->metadata_closed) {
749 ret = 0;
750 goto end;
751 }
752
753 /* Get consumer socket to use to push the metadata.*/
754 socket = consumer_find_socket_by_bitness(registry->bits_per_long,
755 consumer);
756 if (!socket) {
757 ret = -1;
758 goto error;
759 }
760
761 ret = consumer_close_metadata(socket, registry->metadata_key);
762 if (ret < 0) {
763 goto error;
764 }
765
766 error:
767 /*
768 * Metadata closed. Even on error this means that the consumer is not
769 * responding or not found so either way a second close should NOT be emit
770 * for this registry.
771 */
772 registry->metadata_closed = 1;
773 end:
774 pthread_mutex_unlock(&registry->lock);
775 rcu_read_unlock();
776 return ret;
777 }
778
779 /*
780 * We need to execute ht_destroy outside of RCU read-side critical
781 * section and outside of call_rcu thread, so we postpone its execution
782 * using ht_cleanup_push. It is simpler than to change the semantic of
783 * the many callers of delete_ust_app_session().
784 */
785 static
786 void delete_ust_app_session_rcu(struct rcu_head *head)
787 {
788 struct ust_app_session *ua_sess =
789 caa_container_of(head, struct ust_app_session, rcu_head);
790
791 ht_cleanup_push(ua_sess->channels);
792 free(ua_sess);
793 }
794
795 /*
796 * Delete ust app session safely. RCU read lock must be held before calling
797 * this function.
798 *
799 * The session list lock must be held by the caller.
800 */
801 static
802 void delete_ust_app_session(int sock, struct ust_app_session *ua_sess,
803 struct ust_app *app)
804 {
805 int ret;
806 struct lttng_ht_iter iter;
807 struct ust_app_channel *ua_chan;
808 struct ust_registry_session *registry;
809
810 assert(ua_sess);
811
812 pthread_mutex_lock(&ua_sess->lock);
813
814 assert(!ua_sess->deleted);
815 ua_sess->deleted = true;
816
817 registry = get_session_registry(ua_sess);
818 /* Registry can be null on error path during initialization. */
819 if (registry) {
820 /* Push metadata for application before freeing the application. */
821 (void) push_metadata(registry, ua_sess->consumer);
822
823 /*
824 * Don't ask to close metadata for global per UID buffers. Close
825 * metadata only on destroy trace session in this case. Also, the
826 * previous push metadata could have flag the metadata registry to
827 * close so don't send a close command if closed.
828 */
829 if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID) {
830 /* And ask to close it for this session registry. */
831 (void) close_metadata(registry, ua_sess->consumer);
832 }
833 }
834
835 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
836 node.node) {
837 ret = lttng_ht_del(ua_sess->channels, &iter);
838 assert(!ret);
839 delete_ust_app_channel(sock, ua_chan, app);
840 }
841
842 /* In case of per PID, the registry is kept in the session. */
843 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) {
844 struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
845 if (reg_pid) {
846 /*
847 * Registry can be null on error path during
848 * initialization.
849 */
850 buffer_reg_pid_remove(reg_pid);
851 buffer_reg_pid_destroy(reg_pid);
852 }
853 }
854
855 if (ua_sess->handle != -1) {
856 pthread_mutex_lock(&app->sock_lock);
857 ret = ustctl_release_handle(sock, ua_sess->handle);
858 pthread_mutex_unlock(&app->sock_lock);
859 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
860 ERR("UST app sock %d release session handle failed with ret %d",
861 sock, ret);
862 }
863 /* Remove session from application UST object descriptor. */
864 iter.iter.node = &ua_sess->ust_objd_node.node;
865 ret = lttng_ht_del(app->ust_sessions_objd, &iter);
866 assert(!ret);
867 }
868
869 pthread_mutex_unlock(&ua_sess->lock);
870
871 consumer_output_put(ua_sess->consumer);
872
873 call_rcu(&ua_sess->rcu_head, delete_ust_app_session_rcu);
874 }
875
876 /*
877 * Delete a traceable application structure from the global list. Never call
878 * this function outside of a call_rcu call.
879 *
880 * RCU read side lock should _NOT_ be held when calling this function.
881 */
882 static
883 void delete_ust_app(struct ust_app *app)
884 {
885 int ret, sock;
886 struct ust_app_session *ua_sess, *tmp_ua_sess;
887
888 /*
889 * The session list lock must be held during this function to guarantee
890 * the existence of ua_sess.
891 */
892 session_lock_list();
893 /* Delete ust app sessions info */
894 sock = app->sock;
895 app->sock = -1;
896
897 /* Wipe sessions */
898 cds_list_for_each_entry_safe(ua_sess, tmp_ua_sess, &app->teardown_head,
899 teardown_node) {
900 /* Free every object in the session and the session. */
901 rcu_read_lock();
902 delete_ust_app_session(sock, ua_sess, app);
903 rcu_read_unlock();
904 }
905
906 ht_cleanup_push(app->sessions);
907 ht_cleanup_push(app->ust_sessions_objd);
908 ht_cleanup_push(app->ust_objd);
909
910 /*
911 * Wait until we have deleted the application from the sock hash table
912 * before closing this socket, otherwise an application could re-use the
913 * socket ID and race with the teardown, using the same hash table entry.
914 *
915 * It's OK to leave the close in call_rcu. We want it to stay unique for
916 * all RCU readers that could run concurrently with unregister app,
917 * therefore we _need_ to only close that socket after a grace period. So
918 * it should stay in this RCU callback.
919 *
920 * This close() is a very important step of the synchronization model so
921 * every modification to this function must be carefully reviewed.
922 */
923 ret = close(sock);
924 if (ret) {
925 PERROR("close");
926 }
927 lttng_fd_put(LTTNG_FD_APPS, 1);
928
929 DBG2("UST app pid %d deleted", app->pid);
930 free(app);
931 session_unlock_list();
932 }
933
934 /*
935 * URCU intermediate call to delete an UST app.
936 */
937 static
938 void delete_ust_app_rcu(struct rcu_head *head)
939 {
940 struct lttng_ht_node_ulong *node =
941 caa_container_of(head, struct lttng_ht_node_ulong, head);
942 struct ust_app *app =
943 caa_container_of(node, struct ust_app, pid_n);
944
945 DBG3("Call RCU deleting app PID %d", app->pid);
946 delete_ust_app(app);
947 }
948
949 /*
950 * Delete the session from the application ht and delete the data structure by
951 * freeing every object inside and releasing them.
952 *
953 * The session list lock must be held by the caller.
954 */
955 static void destroy_app_session(struct ust_app *app,
956 struct ust_app_session *ua_sess)
957 {
958 int ret;
959 struct lttng_ht_iter iter;
960
961 assert(app);
962 assert(ua_sess);
963
964 iter.iter.node = &ua_sess->node.node;
965 ret = lttng_ht_del(app->sessions, &iter);
966 if (ret) {
967 /* Already scheduled for teardown. */
968 goto end;
969 }
970
971 /* Once deleted, free the data structure. */
972 delete_ust_app_session(app->sock, ua_sess, app);
973
974 end:
975 return;
976 }
977
978 /*
979 * Alloc new UST app session.
980 */
981 static
982 struct ust_app_session *alloc_ust_app_session(struct ust_app *app)
983 {
984 struct ust_app_session *ua_sess;
985
986 /* Init most of the default value by allocating and zeroing */
987 ua_sess = zmalloc(sizeof(struct ust_app_session));
988 if (ua_sess == NULL) {
989 PERROR("malloc");
990 goto error_free;
991 }
992
993 ua_sess->handle = -1;
994 ua_sess->channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
995 ua_sess->metadata_attr.type = LTTNG_UST_CHAN_METADATA;
996 pthread_mutex_init(&ua_sess->lock, NULL);
997
998 return ua_sess;
999
1000 error_free:
1001 return NULL;
1002 }
1003
1004 /*
1005 * Alloc new UST app channel.
1006 */
1007 static
1008 struct ust_app_channel *alloc_ust_app_channel(char *name,
1009 struct ust_app_session *ua_sess,
1010 struct lttng_ust_channel_attr *attr)
1011 {
1012 struct ust_app_channel *ua_chan;
1013
1014 /* Init most of the default value by allocating and zeroing */
1015 ua_chan = zmalloc(sizeof(struct ust_app_channel));
1016 if (ua_chan == NULL) {
1017 PERROR("malloc");
1018 goto error;
1019 }
1020
1021 /* Setup channel name */
1022 strncpy(ua_chan->name, name, sizeof(ua_chan->name));
1023 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
1024
1025 ua_chan->enabled = 1;
1026 ua_chan->handle = -1;
1027 ua_chan->session = ua_sess;
1028 ua_chan->key = get_next_channel_key();
1029 ua_chan->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1030 ua_chan->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
1031 lttng_ht_node_init_str(&ua_chan->node, ua_chan->name);
1032
1033 CDS_INIT_LIST_HEAD(&ua_chan->streams.head);
1034 CDS_INIT_LIST_HEAD(&ua_chan->ctx_list);
1035
1036 /* Copy attributes */
1037 if (attr) {
1038 /* Translate from lttng_ust_channel to ustctl_consumer_channel_attr. */
1039 ua_chan->attr.subbuf_size = attr->subbuf_size;
1040 ua_chan->attr.num_subbuf = attr->num_subbuf;
1041 ua_chan->attr.overwrite = attr->overwrite;
1042 ua_chan->attr.switch_timer_interval = attr->switch_timer_interval;
1043 ua_chan->attr.read_timer_interval = attr->read_timer_interval;
1044 ua_chan->attr.output = attr->output;
1045 ua_chan->attr.blocking_timeout = attr->u.s.blocking_timeout;
1046 }
1047 /* By default, the channel is a per cpu channel. */
1048 ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
1049
1050 DBG3("UST app channel %s allocated", ua_chan->name);
1051
1052 return ua_chan;
1053
1054 error:
1055 return NULL;
1056 }
1057
1058 /*
1059 * Allocate and initialize a UST app stream.
1060 *
1061 * Return newly allocated stream pointer or NULL on error.
1062 */
1063 struct ust_app_stream *ust_app_alloc_stream(void)
1064 {
1065 struct ust_app_stream *stream = NULL;
1066
1067 stream = zmalloc(sizeof(*stream));
1068 if (stream == NULL) {
1069 PERROR("zmalloc ust app stream");
1070 goto error;
1071 }
1072
1073 /* Zero could be a valid value for a handle so flag it to -1. */
1074 stream->handle = -1;
1075
1076 error:
1077 return stream;
1078 }
1079
1080 /*
1081 * Alloc new UST app event.
1082 */
1083 static
1084 struct ust_app_event *alloc_ust_app_event(char *name,
1085 struct lttng_ust_event *attr)
1086 {
1087 struct ust_app_event *ua_event;
1088
1089 /* Init most of the default value by allocating and zeroing */
1090 ua_event = zmalloc(sizeof(struct ust_app_event));
1091 if (ua_event == NULL) {
1092 PERROR("malloc");
1093 goto error;
1094 }
1095
1096 ua_event->enabled = 1;
1097 strncpy(ua_event->name, name, sizeof(ua_event->name));
1098 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
1099 lttng_ht_node_init_str(&ua_event->node, ua_event->name);
1100
1101 /* Copy attributes */
1102 if (attr) {
1103 memcpy(&ua_event->attr, attr, sizeof(ua_event->attr));
1104 }
1105
1106 DBG3("UST app event %s allocated", ua_event->name);
1107
1108 return ua_event;
1109
1110 error:
1111 return NULL;
1112 }
1113
1114 /*
1115 * Alloc new UST app context.
1116 */
1117 static
1118 struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context_attr *uctx)
1119 {
1120 struct ust_app_ctx *ua_ctx;
1121
1122 ua_ctx = zmalloc(sizeof(struct ust_app_ctx));
1123 if (ua_ctx == NULL) {
1124 goto error;
1125 }
1126
1127 CDS_INIT_LIST_HEAD(&ua_ctx->list);
1128
1129 if (uctx) {
1130 memcpy(&ua_ctx->ctx, uctx, sizeof(ua_ctx->ctx));
1131 if (uctx->ctx == LTTNG_UST_CONTEXT_APP_CONTEXT) {
1132 char *provider_name = NULL, *ctx_name = NULL;
1133
1134 provider_name = strdup(uctx->u.app_ctx.provider_name);
1135 ctx_name = strdup(uctx->u.app_ctx.ctx_name);
1136 if (!provider_name || !ctx_name) {
1137 free(provider_name);
1138 free(ctx_name);
1139 goto error;
1140 }
1141
1142 ua_ctx->ctx.u.app_ctx.provider_name = provider_name;
1143 ua_ctx->ctx.u.app_ctx.ctx_name = ctx_name;
1144 }
1145 }
1146
1147 DBG3("UST app context %d allocated", ua_ctx->ctx.ctx);
1148 return ua_ctx;
1149 error:
1150 free(ua_ctx);
1151 return NULL;
1152 }
1153
1154 /*
1155 * Allocate a filter and copy the given original filter.
1156 *
1157 * Return allocated filter or NULL on error.
1158 */
1159 static struct lttng_filter_bytecode *copy_filter_bytecode(
1160 struct lttng_filter_bytecode *orig_f)
1161 {
1162 struct lttng_filter_bytecode *filter = NULL;
1163
1164 /* Copy filter bytecode */
1165 filter = zmalloc(sizeof(*filter) + orig_f->len);
1166 if (!filter) {
1167 PERROR("zmalloc alloc filter bytecode");
1168 goto error;
1169 }
1170
1171 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
1172
1173 error:
1174 return filter;
1175 }
1176
1177 /*
1178 * Create a liblttng-ust filter bytecode from given bytecode.
1179 *
1180 * Return allocated filter or NULL on error.
1181 */
1182 static struct lttng_ust_filter_bytecode *create_ust_bytecode_from_bytecode(
1183 struct lttng_filter_bytecode *orig_f)
1184 {
1185 struct lttng_ust_filter_bytecode *filter = NULL;
1186
1187 /* Copy filter bytecode */
1188 filter = zmalloc(sizeof(*filter) + orig_f->len);
1189 if (!filter) {
1190 PERROR("zmalloc alloc ust filter bytecode");
1191 goto error;
1192 }
1193
1194 assert(sizeof(struct lttng_filter_bytecode) ==
1195 sizeof(struct lttng_ust_filter_bytecode));
1196 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
1197 error:
1198 return filter;
1199 }
1200
1201 /*
1202 * Find an ust_app using the sock and return it. RCU read side lock must be
1203 * held before calling this helper function.
1204 */
1205 struct ust_app *ust_app_find_by_sock(int sock)
1206 {
1207 struct lttng_ht_node_ulong *node;
1208 struct lttng_ht_iter iter;
1209
1210 lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &iter);
1211 node = lttng_ht_iter_get_node_ulong(&iter);
1212 if (node == NULL) {
1213 DBG2("UST app find by sock %d not found", sock);
1214 goto error;
1215 }
1216
1217 return caa_container_of(node, struct ust_app, sock_n);
1218
1219 error:
1220 return NULL;
1221 }
1222
1223 /*
1224 * Find an ust_app using the notify sock and return it. RCU read side lock must
1225 * be held before calling this helper function.
1226 */
1227 static struct ust_app *find_app_by_notify_sock(int sock)
1228 {
1229 struct lttng_ht_node_ulong *node;
1230 struct lttng_ht_iter iter;
1231
1232 lttng_ht_lookup(ust_app_ht_by_notify_sock, (void *)((unsigned long) sock),
1233 &iter);
1234 node = lttng_ht_iter_get_node_ulong(&iter);
1235 if (node == NULL) {
1236 DBG2("UST app find by notify sock %d not found", sock);
1237 goto error;
1238 }
1239
1240 return caa_container_of(node, struct ust_app, notify_sock_n);
1241
1242 error:
1243 return NULL;
1244 }
1245
1246 /*
1247 * Lookup for an ust app event based on event name, filter bytecode and the
1248 * event loglevel.
1249 *
1250 * Return an ust_app_event object or NULL on error.
1251 */
1252 static struct ust_app_event *find_ust_app_event(struct lttng_ht *ht,
1253 char *name, struct lttng_filter_bytecode *filter,
1254 int loglevel_value,
1255 const struct lttng_event_exclusion *exclusion)
1256 {
1257 struct lttng_ht_iter iter;
1258 struct lttng_ht_node_str *node;
1259 struct ust_app_event *event = NULL;
1260 struct ust_app_ht_key key;
1261
1262 assert(name);
1263 assert(ht);
1264
1265 /* Setup key for event lookup. */
1266 key.name = name;
1267 key.filter = filter;
1268 key.loglevel_type = loglevel_value;
1269 /* lttng_event_exclusion and lttng_ust_event_exclusion structures are similar */
1270 key.exclusion = exclusion;
1271
1272 /* Lookup using the event name as hash and a custom match fct. */
1273 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
1274 ht_match_ust_app_event, &key, &iter.iter);
1275 node = lttng_ht_iter_get_node_str(&iter);
1276 if (node == NULL) {
1277 goto end;
1278 }
1279
1280 event = caa_container_of(node, struct ust_app_event, node);
1281
1282 end:
1283 return event;
1284 }
1285
1286 /*
1287 * Create the channel context on the tracer.
1288 *
1289 * Called with UST app session lock held.
1290 */
1291 static
1292 int create_ust_channel_context(struct ust_app_channel *ua_chan,
1293 struct ust_app_ctx *ua_ctx, struct ust_app *app)
1294 {
1295 int ret;
1296
1297 health_code_update();
1298
1299 pthread_mutex_lock(&app->sock_lock);
1300 ret = ustctl_add_context(app->sock, &ua_ctx->ctx,
1301 ua_chan->obj, &ua_ctx->obj);
1302 pthread_mutex_unlock(&app->sock_lock);
1303 if (ret < 0) {
1304 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1305 ERR("UST app create channel context failed for app (pid: %d) "
1306 "with ret %d", app->pid, ret);
1307 } else {
1308 /*
1309 * This is normal behavior, an application can die during the
1310 * creation process. Don't report an error so the execution can
1311 * continue normally.
1312 */
1313 ret = 0;
1314 DBG3("UST app disable event failed. Application is dead.");
1315 }
1316 goto error;
1317 }
1318
1319 ua_ctx->handle = ua_ctx->obj->handle;
1320
1321 DBG2("UST app context handle %d created successfully for channel %s",
1322 ua_ctx->handle, ua_chan->name);
1323
1324 error:
1325 health_code_update();
1326 return ret;
1327 }
1328
1329 /*
1330 * Set the filter on the tracer.
1331 */
1332 static
1333 int set_ust_event_filter(struct ust_app_event *ua_event,
1334 struct ust_app *app)
1335 {
1336 int ret;
1337 struct lttng_ust_filter_bytecode *ust_bytecode = NULL;
1338
1339 health_code_update();
1340
1341 if (!ua_event->filter) {
1342 ret = 0;
1343 goto error;
1344 }
1345
1346 ust_bytecode = create_ust_bytecode_from_bytecode(ua_event->filter);
1347 if (!ust_bytecode) {
1348 ret = -LTTNG_ERR_NOMEM;
1349 goto error;
1350 }
1351 pthread_mutex_lock(&app->sock_lock);
1352 ret = ustctl_set_filter(app->sock, ust_bytecode,
1353 ua_event->obj);
1354 pthread_mutex_unlock(&app->sock_lock);
1355 if (ret < 0) {
1356 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1357 ERR("UST app event %s filter failed for app (pid: %d) "
1358 "with ret %d", ua_event->attr.name, app->pid, ret);
1359 } else {
1360 /*
1361 * This is normal behavior, an application can die during the
1362 * creation process. Don't report an error so the execution can
1363 * continue normally.
1364 */
1365 ret = 0;
1366 DBG3("UST app filter event failed. Application is dead.");
1367 }
1368 goto error;
1369 }
1370
1371 DBG2("UST filter set successfully for event %s", ua_event->name);
1372
1373 error:
1374 health_code_update();
1375 free(ust_bytecode);
1376 return ret;
1377 }
1378
1379 static
1380 struct lttng_ust_event_exclusion *create_ust_exclusion_from_exclusion(
1381 struct lttng_event_exclusion *exclusion)
1382 {
1383 struct lttng_ust_event_exclusion *ust_exclusion = NULL;
1384 size_t exclusion_alloc_size = sizeof(struct lttng_ust_event_exclusion) +
1385 LTTNG_UST_SYM_NAME_LEN * exclusion->count;
1386
1387 ust_exclusion = zmalloc(exclusion_alloc_size);
1388 if (!ust_exclusion) {
1389 PERROR("malloc");
1390 goto end;
1391 }
1392
1393 assert(sizeof(struct lttng_event_exclusion) ==
1394 sizeof(struct lttng_ust_event_exclusion));
1395 memcpy(ust_exclusion, exclusion, exclusion_alloc_size);
1396 end:
1397 return ust_exclusion;
1398 }
1399
1400 /*
1401 * Set event exclusions on the tracer.
1402 */
1403 static
1404 int set_ust_event_exclusion(struct ust_app_event *ua_event,
1405 struct ust_app *app)
1406 {
1407 int ret;
1408 struct lttng_ust_event_exclusion *ust_exclusion = NULL;
1409
1410 health_code_update();
1411
1412 if (!ua_event->exclusion || !ua_event->exclusion->count) {
1413 ret = 0;
1414 goto error;
1415 }
1416
1417 ust_exclusion = create_ust_exclusion_from_exclusion(
1418 ua_event->exclusion);
1419 if (!ust_exclusion) {
1420 ret = -LTTNG_ERR_NOMEM;
1421 goto error;
1422 }
1423 pthread_mutex_lock(&app->sock_lock);
1424 ret = ustctl_set_exclusion(app->sock, ust_exclusion, ua_event->obj);
1425 pthread_mutex_unlock(&app->sock_lock);
1426 if (ret < 0) {
1427 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1428 ERR("UST app event %s exclusions failed for app (pid: %d) "
1429 "with ret %d", ua_event->attr.name, app->pid, ret);
1430 } else {
1431 /*
1432 * This is normal behavior, an application can die during the
1433 * creation process. Don't report an error so the execution can
1434 * continue normally.
1435 */
1436 ret = 0;
1437 DBG3("UST app event exclusion failed. Application is dead.");
1438 }
1439 goto error;
1440 }
1441
1442 DBG2("UST exclusion set successfully for event %s", ua_event->name);
1443
1444 error:
1445 health_code_update();
1446 free(ust_exclusion);
1447 return ret;
1448 }
1449
1450 /*
1451 * Disable the specified event on to UST tracer for the UST session.
1452 */
1453 static int disable_ust_event(struct ust_app *app,
1454 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
1455 {
1456 int ret;
1457
1458 health_code_update();
1459
1460 pthread_mutex_lock(&app->sock_lock);
1461 ret = ustctl_disable(app->sock, ua_event->obj);
1462 pthread_mutex_unlock(&app->sock_lock);
1463 if (ret < 0) {
1464 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1465 ERR("UST app event %s disable failed for app (pid: %d) "
1466 "and session handle %d with ret %d",
1467 ua_event->attr.name, app->pid, ua_sess->handle, ret);
1468 } else {
1469 /*
1470 * This is normal behavior, an application can die during the
1471 * creation process. Don't report an error so the execution can
1472 * continue normally.
1473 */
1474 ret = 0;
1475 DBG3("UST app disable event failed. Application is dead.");
1476 }
1477 goto error;
1478 }
1479
1480 DBG2("UST app event %s disabled successfully for app (pid: %d)",
1481 ua_event->attr.name, app->pid);
1482
1483 error:
1484 health_code_update();
1485 return ret;
1486 }
1487
1488 /*
1489 * Disable the specified channel on to UST tracer for the UST session.
1490 */
1491 static int disable_ust_channel(struct ust_app *app,
1492 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1493 {
1494 int ret;
1495
1496 health_code_update();
1497
1498 pthread_mutex_lock(&app->sock_lock);
1499 ret = ustctl_disable(app->sock, ua_chan->obj);
1500 pthread_mutex_unlock(&app->sock_lock);
1501 if (ret < 0) {
1502 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1503 ERR("UST app channel %s disable failed for app (pid: %d) "
1504 "and session handle %d with ret %d",
1505 ua_chan->name, app->pid, ua_sess->handle, ret);
1506 } else {
1507 /*
1508 * This is normal behavior, an application can die during the
1509 * creation process. Don't report an error so the execution can
1510 * continue normally.
1511 */
1512 ret = 0;
1513 DBG3("UST app disable channel failed. Application is dead.");
1514 }
1515 goto error;
1516 }
1517
1518 DBG2("UST app channel %s disabled successfully for app (pid: %d)",
1519 ua_chan->name, app->pid);
1520
1521 error:
1522 health_code_update();
1523 return ret;
1524 }
1525
1526 /*
1527 * Enable the specified channel on to UST tracer for the UST session.
1528 */
1529 static int enable_ust_channel(struct ust_app *app,
1530 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1531 {
1532 int ret;
1533
1534 health_code_update();
1535
1536 pthread_mutex_lock(&app->sock_lock);
1537 ret = ustctl_enable(app->sock, ua_chan->obj);
1538 pthread_mutex_unlock(&app->sock_lock);
1539 if (ret < 0) {
1540 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1541 ERR("UST app channel %s enable failed for app (pid: %d) "
1542 "and session handle %d with ret %d",
1543 ua_chan->name, app->pid, ua_sess->handle, ret);
1544 } else {
1545 /*
1546 * This is normal behavior, an application can die during the
1547 * creation process. Don't report an error so the execution can
1548 * continue normally.
1549 */
1550 ret = 0;
1551 DBG3("UST app enable channel failed. Application is dead.");
1552 }
1553 goto error;
1554 }
1555
1556 ua_chan->enabled = 1;
1557
1558 DBG2("UST app channel %s enabled successfully for app (pid: %d)",
1559 ua_chan->name, app->pid);
1560
1561 error:
1562 health_code_update();
1563 return ret;
1564 }
1565
1566 /*
1567 * Enable the specified event on to UST tracer for the UST session.
1568 */
1569 static int enable_ust_event(struct ust_app *app,
1570 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
1571 {
1572 int ret;
1573
1574 health_code_update();
1575
1576 pthread_mutex_lock(&app->sock_lock);
1577 ret = ustctl_enable(app->sock, ua_event->obj);
1578 pthread_mutex_unlock(&app->sock_lock);
1579 if (ret < 0) {
1580 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1581 ERR("UST app event %s enable failed for app (pid: %d) "
1582 "and session handle %d with ret %d",
1583 ua_event->attr.name, app->pid, ua_sess->handle, ret);
1584 } else {
1585 /*
1586 * This is normal behavior, an application can die during the
1587 * creation process. Don't report an error so the execution can
1588 * continue normally.
1589 */
1590 ret = 0;
1591 DBG3("UST app enable event failed. Application is dead.");
1592 }
1593 goto error;
1594 }
1595
1596 DBG2("UST app event %s enabled successfully for app (pid: %d)",
1597 ua_event->attr.name, app->pid);
1598
1599 error:
1600 health_code_update();
1601 return ret;
1602 }
1603
1604 /*
1605 * Send channel and stream buffer to application.
1606 *
1607 * Return 0 on success. On error, a negative value is returned.
1608 */
1609 static int send_channel_pid_to_ust(struct ust_app *app,
1610 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1611 {
1612 int ret;
1613 struct ust_app_stream *stream, *stmp;
1614
1615 assert(app);
1616 assert(ua_sess);
1617 assert(ua_chan);
1618
1619 health_code_update();
1620
1621 DBG("UST app sending channel %s to UST app sock %d", ua_chan->name,
1622 app->sock);
1623
1624 /* Send channel to the application. */
1625 ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
1626 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
1627 ret = -ENOTCONN; /* Caused by app exiting. */
1628 goto error;
1629 } else if (ret < 0) {
1630 goto error;
1631 }
1632
1633 health_code_update();
1634
1635 /* Send all streams to application. */
1636 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
1637 ret = ust_consumer_send_stream_to_ust(app, ua_chan, stream);
1638 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
1639 ret = -ENOTCONN; /* Caused by app exiting. */
1640 goto error;
1641 } else if (ret < 0) {
1642 goto error;
1643 }
1644 /* We don't need the stream anymore once sent to the tracer. */
1645 cds_list_del(&stream->list);
1646 delete_ust_app_stream(-1, stream, app);
1647 }
1648 /* Flag the channel that it is sent to the application. */
1649 ua_chan->is_sent = 1;
1650
1651 error:
1652 health_code_update();
1653 return ret;
1654 }
1655
1656 /*
1657 * Create the specified event onto the UST tracer for a UST session.
1658 *
1659 * Should be called with session mutex held.
1660 */
1661 static
1662 int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
1663 struct ust_app_channel *ua_chan, struct ust_app_event *ua_event)
1664 {
1665 int ret = 0;
1666
1667 health_code_update();
1668
1669 /* Create UST event on tracer */
1670 pthread_mutex_lock(&app->sock_lock);
1671 ret = ustctl_create_event(app->sock, &ua_event->attr, ua_chan->obj,
1672 &ua_event->obj);
1673 pthread_mutex_unlock(&app->sock_lock);
1674 if (ret < 0) {
1675 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1676 ERR("Error ustctl create event %s for app pid: %d with ret %d",
1677 ua_event->attr.name, app->pid, ret);
1678 } else {
1679 /*
1680 * This is normal behavior, an application can die during the
1681 * creation process. Don't report an error so the execution can
1682 * continue normally.
1683 */
1684 ret = 0;
1685 DBG3("UST app create event failed. Application is dead.");
1686 }
1687 goto error;
1688 }
1689
1690 ua_event->handle = ua_event->obj->handle;
1691
1692 DBG2("UST app event %s created successfully for pid:%d",
1693 ua_event->attr.name, app->pid);
1694
1695 health_code_update();
1696
1697 /* Set filter if one is present. */
1698 if (ua_event->filter) {
1699 ret = set_ust_event_filter(ua_event, app);
1700 if (ret < 0) {
1701 goto error;
1702 }
1703 }
1704
1705 /* Set exclusions for the event */
1706 if (ua_event->exclusion) {
1707 ret = set_ust_event_exclusion(ua_event, app);
1708 if (ret < 0) {
1709 goto error;
1710 }
1711 }
1712
1713 /* If event not enabled, disable it on the tracer */
1714 if (ua_event->enabled) {
1715 /*
1716 * We now need to explicitly enable the event, since it
1717 * is now disabled at creation.
1718 */
1719 ret = enable_ust_event(app, ua_sess, ua_event);
1720 if (ret < 0) {
1721 /*
1722 * If we hit an EPERM, something is wrong with our enable call. If
1723 * we get an EEXIST, there is a problem on the tracer side since we
1724 * just created it.
1725 */
1726 switch (ret) {
1727 case -LTTNG_UST_ERR_PERM:
1728 /* Code flow problem */
1729 assert(0);
1730 case -LTTNG_UST_ERR_EXIST:
1731 /* It's OK for our use case. */
1732 ret = 0;
1733 break;
1734 default:
1735 break;
1736 }
1737 goto error;
1738 }
1739 }
1740
1741 error:
1742 health_code_update();
1743 return ret;
1744 }
1745
1746 /*
1747 * Copy data between an UST app event and a LTT event.
1748 */
1749 static void shadow_copy_event(struct ust_app_event *ua_event,
1750 struct ltt_ust_event *uevent)
1751 {
1752 size_t exclusion_alloc_size;
1753
1754 strncpy(ua_event->name, uevent->attr.name, sizeof(ua_event->name));
1755 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
1756
1757 ua_event->enabled = uevent->enabled;
1758
1759 /* Copy event attributes */
1760 memcpy(&ua_event->attr, &uevent->attr, sizeof(ua_event->attr));
1761
1762 /* Copy filter bytecode */
1763 if (uevent->filter) {
1764 ua_event->filter = copy_filter_bytecode(uevent->filter);
1765 /* Filter might be NULL here in case of ENONEM. */
1766 }
1767
1768 /* Copy exclusion data */
1769 if (uevent->exclusion) {
1770 exclusion_alloc_size = sizeof(struct lttng_event_exclusion) +
1771 LTTNG_UST_SYM_NAME_LEN * uevent->exclusion->count;
1772 ua_event->exclusion = zmalloc(exclusion_alloc_size);
1773 if (ua_event->exclusion == NULL) {
1774 PERROR("malloc");
1775 } else {
1776 memcpy(ua_event->exclusion, uevent->exclusion,
1777 exclusion_alloc_size);
1778 }
1779 }
1780 }
1781
1782 /*
1783 * Copy data between an UST app channel and a LTT channel.
1784 */
1785 static void shadow_copy_channel(struct ust_app_channel *ua_chan,
1786 struct ltt_ust_channel *uchan)
1787 {
1788 struct lttng_ht_iter iter;
1789 struct ltt_ust_event *uevent;
1790 struct ltt_ust_context *uctx;
1791 struct ust_app_event *ua_event;
1792
1793 DBG2("UST app shadow copy of channel %s started", ua_chan->name);
1794
1795 strncpy(ua_chan->name, uchan->name, sizeof(ua_chan->name));
1796 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
1797
1798 ua_chan->tracefile_size = uchan->tracefile_size;
1799 ua_chan->tracefile_count = uchan->tracefile_count;
1800
1801 /* Copy event attributes since the layout is different. */
1802 ua_chan->attr.subbuf_size = uchan->attr.subbuf_size;
1803 ua_chan->attr.num_subbuf = uchan->attr.num_subbuf;
1804 ua_chan->attr.overwrite = uchan->attr.overwrite;
1805 ua_chan->attr.switch_timer_interval = uchan->attr.switch_timer_interval;
1806 ua_chan->attr.read_timer_interval = uchan->attr.read_timer_interval;
1807 ua_chan->monitor_timer_interval = uchan->monitor_timer_interval;
1808 ua_chan->attr.output = uchan->attr.output;
1809 ua_chan->attr.blocking_timeout = uchan->attr.u.s.blocking_timeout;
1810
1811 /*
1812 * Note that the attribute channel type is not set since the channel on the
1813 * tracing registry side does not have this information.
1814 */
1815
1816 ua_chan->enabled = uchan->enabled;
1817 ua_chan->tracing_channel_id = uchan->id;
1818
1819 cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
1820 struct ust_app_ctx *ua_ctx = alloc_ust_app_ctx(&uctx->ctx);
1821
1822 if (ua_ctx == NULL) {
1823 continue;
1824 }
1825 lttng_ht_node_init_ulong(&ua_ctx->node,
1826 (unsigned long) ua_ctx->ctx.ctx);
1827 lttng_ht_add_ulong(ua_chan->ctx, &ua_ctx->node);
1828 cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list);
1829 }
1830
1831 /* Copy all events from ltt ust channel to ust app channel */
1832 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
1833 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
1834 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
1835 if (ua_event == NULL) {
1836 DBG2("UST event %s not found on shadow copy channel",
1837 uevent->attr.name);
1838 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
1839 if (ua_event == NULL) {
1840 continue;
1841 }
1842 shadow_copy_event(ua_event, uevent);
1843 add_unique_ust_app_event(ua_chan, ua_event);
1844 }
1845 }
1846
1847 DBG3("UST app shadow copy of channel %s done", ua_chan->name);
1848 }
1849
1850 /*
1851 * Copy data between a UST app session and a regular LTT session.
1852 */
1853 static void shadow_copy_session(struct ust_app_session *ua_sess,
1854 struct ltt_ust_session *usess, struct ust_app *app)
1855 {
1856 struct lttng_ht_node_str *ua_chan_node;
1857 struct lttng_ht_iter iter;
1858 struct ltt_ust_channel *uchan;
1859 struct ust_app_channel *ua_chan;
1860 time_t rawtime;
1861 struct tm *timeinfo;
1862 char datetime[16];
1863 int ret;
1864 char tmp_shm_path[PATH_MAX];
1865
1866 /* Get date and time for unique app path */
1867 time(&rawtime);
1868 timeinfo = localtime(&rawtime);
1869 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
1870
1871 DBG2("Shadow copy of session handle %d", ua_sess->handle);
1872
1873 ua_sess->tracing_id = usess->id;
1874 ua_sess->id = get_next_session_id();
1875 ua_sess->uid = app->uid;
1876 ua_sess->gid = app->gid;
1877 ua_sess->euid = usess->uid;
1878 ua_sess->egid = usess->gid;
1879 ua_sess->buffer_type = usess->buffer_type;
1880 ua_sess->bits_per_long = app->bits_per_long;
1881
1882 /* There is only one consumer object per session possible. */
1883 consumer_output_get(usess->consumer);
1884 ua_sess->consumer = usess->consumer;
1885
1886 ua_sess->output_traces = usess->output_traces;
1887 ua_sess->live_timer_interval = usess->live_timer_interval;
1888 copy_channel_attr_to_ustctl(&ua_sess->metadata_attr,
1889 &usess->metadata_attr);
1890
1891 switch (ua_sess->buffer_type) {
1892 case LTTNG_BUFFER_PER_PID:
1893 ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
1894 DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s", app->name, app->pid,
1895 datetime);
1896 break;
1897 case LTTNG_BUFFER_PER_UID:
1898 ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
1899 DEFAULT_UST_TRACE_UID_PATH, ua_sess->uid, app->bits_per_long);
1900 break;
1901 default:
1902 assert(0);
1903 goto error;
1904 }
1905 if (ret < 0) {
1906 PERROR("asprintf UST shadow copy session");
1907 assert(0);
1908 goto error;
1909 }
1910
1911 strncpy(ua_sess->root_shm_path, usess->root_shm_path,
1912 sizeof(ua_sess->root_shm_path));
1913 ua_sess->root_shm_path[sizeof(ua_sess->root_shm_path) - 1] = '\0';
1914 strncpy(ua_sess->shm_path, usess->shm_path,
1915 sizeof(ua_sess->shm_path));
1916 ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0';
1917 if (ua_sess->shm_path[0]) {
1918 switch (ua_sess->buffer_type) {
1919 case LTTNG_BUFFER_PER_PID:
1920 ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path),
1921 DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s",
1922 app->name, app->pid, datetime);
1923 break;
1924 case LTTNG_BUFFER_PER_UID:
1925 ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path),
1926 DEFAULT_UST_TRACE_UID_PATH,
1927 app->uid, app->bits_per_long);
1928 break;
1929 default:
1930 assert(0);
1931 goto error;
1932 }
1933 if (ret < 0) {
1934 PERROR("sprintf UST shadow copy session");
1935 assert(0);
1936 goto error;
1937 }
1938 strncat(ua_sess->shm_path, tmp_shm_path,
1939 sizeof(ua_sess->shm_path) - strlen(ua_sess->shm_path) - 1);
1940 ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0';
1941 }
1942
1943 /* Iterate over all channels in global domain. */
1944 cds_lfht_for_each_entry(usess->domain_global.channels->ht, &iter.iter,
1945 uchan, node.node) {
1946 struct lttng_ht_iter uiter;
1947
1948 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
1949 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
1950 if (ua_chan_node != NULL) {
1951 /* Session exist. Contiuing. */
1952 continue;
1953 }
1954
1955 DBG2("Channel %s not found on shadow session copy, creating it",
1956 uchan->name);
1957 ua_chan = alloc_ust_app_channel(uchan->name, ua_sess,
1958 &uchan->attr);
1959 if (ua_chan == NULL) {
1960 /* malloc failed FIXME: Might want to do handle ENOMEM .. */
1961 continue;
1962 }
1963 shadow_copy_channel(ua_chan, uchan);
1964 /*
1965 * The concept of metadata channel does not exist on the tracing
1966 * registry side of the session daemon so this can only be a per CPU
1967 * channel and not metadata.
1968 */
1969 ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
1970
1971 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
1972 }
1973 return;
1974
1975 error:
1976 consumer_output_put(ua_sess->consumer);
1977 }
1978
1979 /*
1980 * Lookup sesison wrapper.
1981 */
1982 static
1983 void __lookup_session_by_app(struct ltt_ust_session *usess,
1984 struct ust_app *app, struct lttng_ht_iter *iter)
1985 {
1986 /* Get right UST app session from app */
1987 lttng_ht_lookup(app->sessions, &usess->id, iter);
1988 }
1989
1990 /*
1991 * Return ust app session from the app session hashtable using the UST session
1992 * id.
1993 */
1994 static struct ust_app_session *lookup_session_by_app(
1995 struct ltt_ust_session *usess, struct ust_app *app)
1996 {
1997 struct lttng_ht_iter iter;
1998 struct lttng_ht_node_u64 *node;
1999
2000 __lookup_session_by_app(usess, app, &iter);
2001 node = lttng_ht_iter_get_node_u64(&iter);
2002 if (node == NULL) {
2003 goto error;
2004 }
2005
2006 return caa_container_of(node, struct ust_app_session, node);
2007
2008 error:
2009 return NULL;
2010 }
2011
2012 /*
2013 * Setup buffer registry per PID for the given session and application. If none
2014 * is found, a new one is created, added to the global registry and
2015 * initialized. If regp is valid, it's set with the newly created object.
2016 *
2017 * Return 0 on success or else a negative value.
2018 */
2019 static int setup_buffer_reg_pid(struct ust_app_session *ua_sess,
2020 struct ust_app *app, struct buffer_reg_pid **regp)
2021 {
2022 int ret = 0;
2023 struct buffer_reg_pid *reg_pid;
2024
2025 assert(ua_sess);
2026 assert(app);
2027
2028 rcu_read_lock();
2029
2030 reg_pid = buffer_reg_pid_find(ua_sess->id);
2031 if (!reg_pid) {
2032 /*
2033 * This is the create channel path meaning that if there is NO
2034 * registry available, we have to create one for this session.
2035 */
2036 ret = buffer_reg_pid_create(ua_sess->id, &reg_pid,
2037 ua_sess->root_shm_path, ua_sess->shm_path);
2038 if (ret < 0) {
2039 goto error;
2040 }
2041 } else {
2042 goto end;
2043 }
2044
2045 /* Initialize registry. */
2046 ret = ust_registry_session_init(&reg_pid->registry->reg.ust, app,
2047 app->bits_per_long, app->uint8_t_alignment,
2048 app->uint16_t_alignment, app->uint32_t_alignment,
2049 app->uint64_t_alignment, app->long_alignment,
2050 app->byte_order, app->version.major,
2051 app->version.minor, reg_pid->root_shm_path,
2052 reg_pid->shm_path,
2053 ua_sess->euid, ua_sess->egid);
2054 if (ret < 0) {
2055 /*
2056 * reg_pid->registry->reg.ust is NULL upon error, so we need to
2057 * destroy the buffer registry, because it is always expected
2058 * that if the buffer registry can be found, its ust registry is
2059 * non-NULL.
2060 */
2061 buffer_reg_pid_destroy(reg_pid);
2062 goto error;
2063 }
2064
2065 buffer_reg_pid_add(reg_pid);
2066
2067 DBG3("UST app buffer registry per PID created successfully");
2068
2069 end:
2070 if (regp) {
2071 *regp = reg_pid;
2072 }
2073 error:
2074 rcu_read_unlock();
2075 return ret;
2076 }
2077
2078 /*
2079 * Setup buffer registry per UID for the given session and application. If none
2080 * is found, a new one is created, added to the global registry and
2081 * initialized. If regp is valid, it's set with the newly created object.
2082 *
2083 * Return 0 on success or else a negative value.
2084 */
2085 static int setup_buffer_reg_uid(struct ltt_ust_session *usess,
2086 struct ust_app_session *ua_sess,
2087 struct ust_app *app, struct buffer_reg_uid **regp)
2088 {
2089 int ret = 0;
2090 struct buffer_reg_uid *reg_uid;
2091
2092 assert(usess);
2093 assert(app);
2094
2095 rcu_read_lock();
2096
2097 reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
2098 if (!reg_uid) {
2099 /*
2100 * This is the create channel path meaning that if there is NO
2101 * registry available, we have to create one for this session.
2102 */
2103 ret = buffer_reg_uid_create(usess->id, app->bits_per_long, app->uid,
2104 LTTNG_DOMAIN_UST, &reg_uid,
2105 ua_sess->root_shm_path, ua_sess->shm_path);
2106 if (ret < 0) {
2107 goto error;
2108 }
2109 } else {
2110 goto end;
2111 }
2112
2113 /* Initialize registry. */
2114 ret = ust_registry_session_init(&reg_uid->registry->reg.ust, NULL,
2115 app->bits_per_long, app->uint8_t_alignment,
2116 app->uint16_t_alignment, app->uint32_t_alignment,
2117 app->uint64_t_alignment, app->long_alignment,
2118 app->byte_order, app->version.major,
2119 app->version.minor, reg_uid->root_shm_path,
2120 reg_uid->shm_path, usess->uid, usess->gid);
2121 if (ret < 0) {
2122 /*
2123 * reg_uid->registry->reg.ust is NULL upon error, so we need to
2124 * destroy the buffer registry, because it is always expected
2125 * that if the buffer registry can be found, its ust registry is
2126 * non-NULL.
2127 */
2128 buffer_reg_uid_destroy(reg_uid, NULL);
2129 goto error;
2130 }
2131 /* Add node to teardown list of the session. */
2132 cds_list_add(&reg_uid->lnode, &usess->buffer_reg_uid_list);
2133
2134 buffer_reg_uid_add(reg_uid);
2135
2136 DBG3("UST app buffer registry per UID created successfully");
2137 end:
2138 if (regp) {
2139 *regp = reg_uid;
2140 }
2141 error:
2142 rcu_read_unlock();
2143 return ret;
2144 }
2145
2146 /*
2147 * Create a session on the tracer side for the given app.
2148 *
2149 * On success, ua_sess_ptr is populated with the session pointer or else left
2150 * untouched. If the session was created, is_created is set to 1. On error,
2151 * it's left untouched. Note that ua_sess_ptr is mandatory but is_created can
2152 * be NULL.
2153 *
2154 * Returns 0 on success or else a negative code which is either -ENOMEM or
2155 * -ENOTCONN which is the default code if the ustctl_create_session fails.
2156 */
2157 static int find_or_create_ust_app_session(struct ltt_ust_session *usess,
2158 struct ust_app *app, struct ust_app_session **ua_sess_ptr,
2159 int *is_created)
2160 {
2161 int ret, created = 0;
2162 struct ust_app_session *ua_sess;
2163
2164 assert(usess);
2165 assert(app);
2166 assert(ua_sess_ptr);
2167
2168 health_code_update();
2169
2170 ua_sess = lookup_session_by_app(usess, app);
2171 if (ua_sess == NULL) {
2172 DBG2("UST app pid: %d session id %" PRIu64 " not found, creating it",
2173 app->pid, usess->id);
2174 ua_sess = alloc_ust_app_session(app);
2175 if (ua_sess == NULL) {
2176 /* Only malloc can failed so something is really wrong */
2177 ret = -ENOMEM;
2178 goto error;
2179 }
2180 shadow_copy_session(ua_sess, usess, app);
2181 created = 1;
2182 }
2183
2184 switch (usess->buffer_type) {
2185 case LTTNG_BUFFER_PER_PID:
2186 /* Init local registry. */
2187 ret = setup_buffer_reg_pid(ua_sess, app, NULL);
2188 if (ret < 0) {
2189 delete_ust_app_session(-1, ua_sess, app);
2190 goto error;
2191 }
2192 break;
2193 case LTTNG_BUFFER_PER_UID:
2194 /* Look for a global registry. If none exists, create one. */
2195 ret = setup_buffer_reg_uid(usess, ua_sess, app, NULL);
2196 if (ret < 0) {
2197 delete_ust_app_session(-1, ua_sess, app);
2198 goto error;
2199 }
2200 break;
2201 default:
2202 assert(0);
2203 ret = -EINVAL;
2204 goto error;
2205 }
2206
2207 health_code_update();
2208
2209 if (ua_sess->handle == -1) {
2210 pthread_mutex_lock(&app->sock_lock);
2211 ret = ustctl_create_session(app->sock);
2212 pthread_mutex_unlock(&app->sock_lock);
2213 if (ret < 0) {
2214 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
2215 ERR("Creating session for app pid %d with ret %d",
2216 app->pid, ret);
2217 } else {
2218 DBG("UST app creating session failed. Application is dead");
2219 /*
2220 * This is normal behavior, an application can die during the
2221 * creation process. Don't report an error so the execution can
2222 * continue normally. This will get flagged ENOTCONN and the
2223 * caller will handle it.
2224 */
2225 ret = 0;
2226 }
2227 delete_ust_app_session(-1, ua_sess, app);
2228 if (ret != -ENOMEM) {
2229 /*
2230 * Tracer is probably gone or got an internal error so let's
2231 * behave like it will soon unregister or not usable.
2232 */
2233 ret = -ENOTCONN;
2234 }
2235 goto error;
2236 }
2237
2238 ua_sess->handle = ret;
2239
2240 /* Add ust app session to app's HT */
2241 lttng_ht_node_init_u64(&ua_sess->node,
2242 ua_sess->tracing_id);
2243 lttng_ht_add_unique_u64(app->sessions, &ua_sess->node);
2244 lttng_ht_node_init_ulong(&ua_sess->ust_objd_node, ua_sess->handle);
2245 lttng_ht_add_unique_ulong(app->ust_sessions_objd,
2246 &ua_sess->ust_objd_node);
2247
2248 DBG2("UST app session created successfully with handle %d", ret);
2249 }
2250
2251 *ua_sess_ptr = ua_sess;
2252 if (is_created) {
2253 *is_created = created;
2254 }
2255
2256 /* Everything went well. */
2257 ret = 0;
2258
2259 error:
2260 health_code_update();
2261 return ret;
2262 }
2263
2264 /*
2265 * Match function for a hash table lookup of ust_app_ctx.
2266 *
2267 * It matches an ust app context based on the context type and, in the case
2268 * of perf counters, their name.
2269 */
2270 static int ht_match_ust_app_ctx(struct cds_lfht_node *node, const void *_key)
2271 {
2272 struct ust_app_ctx *ctx;
2273 const struct lttng_ust_context_attr *key;
2274
2275 assert(node);
2276 assert(_key);
2277
2278 ctx = caa_container_of(node, struct ust_app_ctx, node.node);
2279 key = _key;
2280
2281 /* Context type */
2282 if (ctx->ctx.ctx != key->ctx) {
2283 goto no_match;
2284 }
2285
2286 switch(key->ctx) {
2287 case LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER:
2288 if (strncmp(key->u.perf_counter.name,
2289 ctx->ctx.u.perf_counter.name,
2290 sizeof(key->u.perf_counter.name))) {
2291 goto no_match;
2292 }
2293 break;
2294 case LTTNG_UST_CONTEXT_APP_CONTEXT:
2295 if (strcmp(key->u.app_ctx.provider_name,
2296 ctx->ctx.u.app_ctx.provider_name) ||
2297 strcmp(key->u.app_ctx.ctx_name,
2298 ctx->ctx.u.app_ctx.ctx_name)) {
2299 goto no_match;
2300 }
2301 break;
2302 default:
2303 break;
2304 }
2305
2306 /* Match. */
2307 return 1;
2308
2309 no_match:
2310 return 0;
2311 }
2312
2313 /*
2314 * Lookup for an ust app context from an lttng_ust_context.
2315 *
2316 * Must be called while holding RCU read side lock.
2317 * Return an ust_app_ctx object or NULL on error.
2318 */
2319 static
2320 struct ust_app_ctx *find_ust_app_context(struct lttng_ht *ht,
2321 struct lttng_ust_context_attr *uctx)
2322 {
2323 struct lttng_ht_iter iter;
2324 struct lttng_ht_node_ulong *node;
2325 struct ust_app_ctx *app_ctx = NULL;
2326
2327 assert(uctx);
2328 assert(ht);
2329
2330 /* Lookup using the lttng_ust_context_type and a custom match fct. */
2331 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) uctx->ctx, lttng_ht_seed),
2332 ht_match_ust_app_ctx, uctx, &iter.iter);
2333 node = lttng_ht_iter_get_node_ulong(&iter);
2334 if (!node) {
2335 goto end;
2336 }
2337
2338 app_ctx = caa_container_of(node, struct ust_app_ctx, node);
2339
2340 end:
2341 return app_ctx;
2342 }
2343
2344 /*
2345 * Create a context for the channel on the tracer.
2346 *
2347 * Called with UST app session lock held and a RCU read side lock.
2348 */
2349 static
2350 int create_ust_app_channel_context(struct ust_app_session *ua_sess,
2351 struct ust_app_channel *ua_chan,
2352 struct lttng_ust_context_attr *uctx,
2353 struct ust_app *app)
2354 {
2355 int ret = 0;
2356 struct ust_app_ctx *ua_ctx;
2357
2358 DBG2("UST app adding context to channel %s", ua_chan->name);
2359
2360 ua_ctx = find_ust_app_context(ua_chan->ctx, uctx);
2361 if (ua_ctx) {
2362 ret = -EEXIST;
2363 goto error;
2364 }
2365
2366 ua_ctx = alloc_ust_app_ctx(uctx);
2367 if (ua_ctx == NULL) {
2368 /* malloc failed */
2369 ret = -ENOMEM;
2370 goto error;
2371 }
2372
2373 lttng_ht_node_init_ulong(&ua_ctx->node, (unsigned long) ua_ctx->ctx.ctx);
2374 lttng_ht_add_ulong(ua_chan->ctx, &ua_ctx->node);
2375 cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list);
2376
2377 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
2378 if (ret < 0) {
2379 goto error;
2380 }
2381
2382 error:
2383 return ret;
2384 }
2385
2386 /*
2387 * Enable on the tracer side a ust app event for the session and channel.
2388 *
2389 * Called with UST app session lock held.
2390 */
2391 static
2392 int enable_ust_app_event(struct ust_app_session *ua_sess,
2393 struct ust_app_event *ua_event, struct ust_app *app)
2394 {
2395 int ret;
2396
2397 ret = enable_ust_event(app, ua_sess, ua_event);
2398 if (ret < 0) {
2399 goto error;
2400 }
2401
2402 ua_event->enabled = 1;
2403
2404 error:
2405 return ret;
2406 }
2407
2408 /*
2409 * Disable on the tracer side a ust app event for the session and channel.
2410 */
2411 static int disable_ust_app_event(struct ust_app_session *ua_sess,
2412 struct ust_app_event *ua_event, struct ust_app *app)
2413 {
2414 int ret;
2415
2416 ret = disable_ust_event(app, ua_sess, ua_event);
2417 if (ret < 0) {
2418 goto error;
2419 }
2420
2421 ua_event->enabled = 0;
2422
2423 error:
2424 return ret;
2425 }
2426
2427 /*
2428 * Lookup ust app channel for session and disable it on the tracer side.
2429 */
2430 static
2431 int disable_ust_app_channel(struct ust_app_session *ua_sess,
2432 struct ust_app_channel *ua_chan, struct ust_app *app)
2433 {
2434 int ret;
2435
2436 ret = disable_ust_channel(app, ua_sess, ua_chan);
2437 if (ret < 0) {
2438 goto error;
2439 }
2440
2441 ua_chan->enabled = 0;
2442
2443 error:
2444 return ret;
2445 }
2446
2447 /*
2448 * Lookup ust app channel for session and enable it on the tracer side. This
2449 * MUST be called with a RCU read side lock acquired.
2450 */
2451 static int enable_ust_app_channel(struct ust_app_session *ua_sess,
2452 struct ltt_ust_channel *uchan, struct ust_app *app)
2453 {
2454 int ret = 0;
2455 struct lttng_ht_iter iter;
2456 struct lttng_ht_node_str *ua_chan_node;
2457 struct ust_app_channel *ua_chan;
2458
2459 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
2460 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
2461 if (ua_chan_node == NULL) {
2462 DBG2("Unable to find channel %s in ust session id %" PRIu64,
2463 uchan->name, ua_sess->tracing_id);
2464 goto error;
2465 }
2466
2467 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2468
2469 ret = enable_ust_channel(app, ua_sess, ua_chan);
2470 if (ret < 0) {
2471 goto error;
2472 }
2473
2474 error:
2475 return ret;
2476 }
2477
2478 /*
2479 * Ask the consumer to create a channel and get it if successful.
2480 *
2481 * Called with UST app session lock held.
2482 *
2483 * Return 0 on success or else a negative value.
2484 */
2485 static int do_consumer_create_channel(struct ltt_ust_session *usess,
2486 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan,
2487 int bitness, struct ust_registry_session *registry)
2488 {
2489 int ret;
2490 unsigned int nb_fd = 0;
2491 struct consumer_socket *socket;
2492
2493 assert(usess);
2494 assert(ua_sess);
2495 assert(ua_chan);
2496 assert(registry);
2497
2498 rcu_read_lock();
2499 health_code_update();
2500
2501 /* Get the right consumer socket for the application. */
2502 socket = consumer_find_socket_by_bitness(bitness, usess->consumer);
2503 if (!socket) {
2504 ret = -EINVAL;
2505 goto error;
2506 }
2507
2508 health_code_update();
2509
2510 /* Need one fd for the channel. */
2511 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2512 if (ret < 0) {
2513 ERR("Exhausted number of available FD upon create channel");
2514 goto error;
2515 }
2516
2517 /*
2518 * Ask consumer to create channel. The consumer will return the number of
2519 * stream we have to expect.
2520 */
2521 ret = ust_consumer_ask_channel(ua_sess, ua_chan, usess->consumer, socket,
2522 registry);
2523 if (ret < 0) {
2524 goto error_ask;
2525 }
2526
2527 /*
2528 * Compute the number of fd needed before receiving them. It must be 2 per
2529 * stream (2 being the default value here).
2530 */
2531 nb_fd = DEFAULT_UST_STREAM_FD_NUM * ua_chan->expected_stream_count;
2532
2533 /* Reserve the amount of file descriptor we need. */
2534 ret = lttng_fd_get(LTTNG_FD_APPS, nb_fd);
2535 if (ret < 0) {
2536 ERR("Exhausted number of available FD upon create channel");
2537 goto error_fd_get_stream;
2538 }
2539
2540 health_code_update();
2541
2542 /*
2543 * Now get the channel from the consumer. This call wil populate the stream
2544 * list of that channel and set the ust objects.
2545 */
2546 if (usess->consumer->enabled) {
2547 ret = ust_consumer_get_channel(socket, ua_chan);
2548 if (ret < 0) {
2549 goto error_destroy;
2550 }
2551 }
2552
2553 rcu_read_unlock();
2554 return 0;
2555
2556 error_destroy:
2557 lttng_fd_put(LTTNG_FD_APPS, nb_fd);
2558 error_fd_get_stream:
2559 /*
2560 * Initiate a destroy channel on the consumer since we had an error
2561 * handling it on our side. The return value is of no importance since we
2562 * already have a ret value set by the previous error that we need to
2563 * return.
2564 */
2565 (void) ust_consumer_destroy_channel(socket, ua_chan);
2566 error_ask:
2567 lttng_fd_put(LTTNG_FD_APPS, 1);
2568 error:
2569 health_code_update();
2570 rcu_read_unlock();
2571 return ret;
2572 }
2573
2574 /*
2575 * Duplicate the ust data object of the ust app stream and save it in the
2576 * buffer registry stream.
2577 *
2578 * Return 0 on success or else a negative value.
2579 */
2580 static int duplicate_stream_object(struct buffer_reg_stream *reg_stream,
2581 struct ust_app_stream *stream)
2582 {
2583 int ret;
2584
2585 assert(reg_stream);
2586 assert(stream);
2587
2588 /* Reserve the amount of file descriptor we need. */
2589 ret = lttng_fd_get(LTTNG_FD_APPS, 2);
2590 if (ret < 0) {
2591 ERR("Exhausted number of available FD upon duplicate stream");
2592 goto error;
2593 }
2594
2595 /* Duplicate object for stream once the original is in the registry. */
2596 ret = ustctl_duplicate_ust_object_data(&stream->obj,
2597 reg_stream->obj.ust);
2598 if (ret < 0) {
2599 ERR("Duplicate stream obj from %p to %p failed with ret %d",
2600 reg_stream->obj.ust, stream->obj, ret);
2601 lttng_fd_put(LTTNG_FD_APPS, 2);
2602 goto error;
2603 }
2604 stream->handle = stream->obj->handle;
2605
2606 error:
2607 return ret;
2608 }
2609
2610 /*
2611 * Duplicate the ust data object of the ust app. channel and save it in the
2612 * buffer registry channel.
2613 *
2614 * Return 0 on success or else a negative value.
2615 */
2616 static int duplicate_channel_object(struct buffer_reg_channel *reg_chan,
2617 struct ust_app_channel *ua_chan)
2618 {
2619 int ret;
2620
2621 assert(reg_chan);
2622 assert(ua_chan);
2623
2624 /* Need two fds for the channel. */
2625 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2626 if (ret < 0) {
2627 ERR("Exhausted number of available FD upon duplicate channel");
2628 goto error_fd_get;
2629 }
2630
2631 /* Duplicate object for stream once the original is in the registry. */
2632 ret = ustctl_duplicate_ust_object_data(&ua_chan->obj, reg_chan->obj.ust);
2633 if (ret < 0) {
2634 ERR("Duplicate channel obj from %p to %p failed with ret: %d",
2635 reg_chan->obj.ust, ua_chan->obj, ret);
2636 goto error;
2637 }
2638 ua_chan->handle = ua_chan->obj->handle;
2639
2640 return 0;
2641
2642 error:
2643 lttng_fd_put(LTTNG_FD_APPS, 1);
2644 error_fd_get:
2645 return ret;
2646 }
2647
2648 /*
2649 * For a given channel buffer registry, setup all streams of the given ust
2650 * application channel.
2651 *
2652 * Return 0 on success or else a negative value.
2653 */
2654 static int setup_buffer_reg_streams(struct buffer_reg_channel *reg_chan,
2655 struct ust_app_channel *ua_chan,
2656 struct ust_app *app)
2657 {
2658 int ret = 0;
2659 struct ust_app_stream *stream, *stmp;
2660
2661 assert(reg_chan);
2662 assert(ua_chan);
2663
2664 DBG2("UST app setup buffer registry stream");
2665
2666 /* Send all streams to application. */
2667 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
2668 struct buffer_reg_stream *reg_stream;
2669
2670 ret = buffer_reg_stream_create(&reg_stream);
2671 if (ret < 0) {
2672 goto error;
2673 }
2674
2675 /*
2676 * Keep original pointer and nullify it in the stream so the delete
2677 * stream call does not release the object.
2678 */
2679 reg_stream->obj.ust = stream->obj;
2680 stream->obj = NULL;
2681 buffer_reg_stream_add(reg_stream, reg_chan);
2682
2683 /* We don't need the streams anymore. */
2684 cds_list_del(&stream->list);
2685 delete_ust_app_stream(-1, stream, app);
2686 }
2687
2688 error:
2689 return ret;
2690 }
2691
2692 /*
2693 * Create a buffer registry channel for the given session registry and
2694 * application channel object. If regp pointer is valid, it's set with the
2695 * created object. Important, the created object is NOT added to the session
2696 * registry hash table.
2697 *
2698 * Return 0 on success else a negative value.
2699 */
2700 static int create_buffer_reg_channel(struct buffer_reg_session *reg_sess,
2701 struct ust_app_channel *ua_chan, struct buffer_reg_channel **regp)
2702 {
2703 int ret;
2704 struct buffer_reg_channel *reg_chan = NULL;
2705
2706 assert(reg_sess);
2707 assert(ua_chan);
2708
2709 DBG2("UST app creating buffer registry channel for %s", ua_chan->name);
2710
2711 /* Create buffer registry channel. */
2712 ret = buffer_reg_channel_create(ua_chan->tracing_channel_id, &reg_chan);
2713 if (ret < 0) {
2714 goto error_create;
2715 }
2716 assert(reg_chan);
2717 reg_chan->consumer_key = ua_chan->key;
2718 reg_chan->subbuf_size = ua_chan->attr.subbuf_size;
2719 reg_chan->num_subbuf = ua_chan->attr.num_subbuf;
2720
2721 /* Create and add a channel registry to session. */
2722 ret = ust_registry_channel_add(reg_sess->reg.ust,
2723 ua_chan->tracing_channel_id);
2724 if (ret < 0) {
2725 goto error;
2726 }
2727 buffer_reg_channel_add(reg_sess, reg_chan);
2728
2729 if (regp) {
2730 *regp = reg_chan;
2731 }
2732
2733 return 0;
2734
2735 error:
2736 /* Safe because the registry channel object was not added to any HT. */
2737 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2738 error_create:
2739 return ret;
2740 }
2741
2742 /*
2743 * Setup buffer registry channel for the given session registry and application
2744 * channel object. If regp pointer is valid, it's set with the created object.
2745 *
2746 * Return 0 on success else a negative value.
2747 */
2748 static int setup_buffer_reg_channel(struct buffer_reg_session *reg_sess,
2749 struct ust_app_channel *ua_chan, struct buffer_reg_channel *reg_chan,
2750 struct ust_app *app)
2751 {
2752 int ret;
2753
2754 assert(reg_sess);
2755 assert(reg_chan);
2756 assert(ua_chan);
2757 assert(ua_chan->obj);
2758
2759 DBG2("UST app setup buffer registry channel for %s", ua_chan->name);
2760
2761 /* Setup all streams for the registry. */
2762 ret = setup_buffer_reg_streams(reg_chan, ua_chan, app);
2763 if (ret < 0) {
2764 goto error;
2765 }
2766
2767 reg_chan->obj.ust = ua_chan->obj;
2768 ua_chan->obj = NULL;
2769
2770 return 0;
2771
2772 error:
2773 buffer_reg_channel_remove(reg_sess, reg_chan);
2774 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2775 return ret;
2776 }
2777
2778 /*
2779 * Send buffer registry channel to the application.
2780 *
2781 * Return 0 on success else a negative value.
2782 */
2783 static int send_channel_uid_to_ust(struct buffer_reg_channel *reg_chan,
2784 struct ust_app *app, struct ust_app_session *ua_sess,
2785 struct ust_app_channel *ua_chan)
2786 {
2787 int ret;
2788 struct buffer_reg_stream *reg_stream;
2789
2790 assert(reg_chan);
2791 assert(app);
2792 assert(ua_sess);
2793 assert(ua_chan);
2794
2795 DBG("UST app sending buffer registry channel to ust sock %d", app->sock);
2796
2797 ret = duplicate_channel_object(reg_chan, ua_chan);
2798 if (ret < 0) {
2799 goto error;
2800 }
2801
2802 /* Send channel to the application. */
2803 ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
2804 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
2805 ret = -ENOTCONN; /* Caused by app exiting. */
2806 goto error;
2807 } else if (ret < 0) {
2808 goto error;
2809 }
2810
2811 health_code_update();
2812
2813 /* Send all streams to application. */
2814 pthread_mutex_lock(&reg_chan->stream_list_lock);
2815 cds_list_for_each_entry(reg_stream, &reg_chan->streams, lnode) {
2816 struct ust_app_stream stream;
2817
2818 ret = duplicate_stream_object(reg_stream, &stream);
2819 if (ret < 0) {
2820 goto error_stream_unlock;
2821 }
2822
2823 ret = ust_consumer_send_stream_to_ust(app, ua_chan, &stream);
2824 if (ret < 0) {
2825 (void) release_ust_app_stream(-1, &stream, app);
2826 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
2827 ret = -ENOTCONN; /* Caused by app exiting. */
2828 }
2829 goto error_stream_unlock;
2830 }
2831
2832 /*
2833 * The return value is not important here. This function will output an
2834 * error if needed.
2835 */
2836 (void) release_ust_app_stream(-1, &stream, app);
2837 }
2838 ua_chan->is_sent = 1;
2839
2840 error_stream_unlock:
2841 pthread_mutex_unlock(&reg_chan->stream_list_lock);
2842 error:
2843 return ret;
2844 }
2845
2846 /*
2847 * Create and send to the application the created buffers with per UID buffers.
2848 *
2849 * This MUST be called with a RCU read side lock acquired.
2850 *
2851 * Return 0 on success else a negative value.
2852 */
2853 static int create_channel_per_uid(struct ust_app *app,
2854 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2855 struct ust_app_channel *ua_chan)
2856 {
2857 int ret;
2858 struct buffer_reg_uid *reg_uid;
2859 struct buffer_reg_channel *reg_chan;
2860 bool created = false;
2861
2862 assert(app);
2863 assert(usess);
2864 assert(ua_sess);
2865 assert(ua_chan);
2866
2867 DBG("UST app creating channel %s with per UID buffers", ua_chan->name);
2868
2869 reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
2870 /*
2871 * The session creation handles the creation of this global registry
2872 * object. If none can be find, there is a code flow problem or a
2873 * teardown race.
2874 */
2875 assert(reg_uid);
2876
2877 reg_chan = buffer_reg_channel_find(ua_chan->tracing_channel_id,
2878 reg_uid);
2879 if (!reg_chan) {
2880 /* Create the buffer registry channel object. */
2881 ret = create_buffer_reg_channel(reg_uid->registry, ua_chan, &reg_chan);
2882 if (ret < 0) {
2883 ERR("Error creating the UST channel \"%s\" registry instance",
2884 ua_chan->name);
2885 goto error;
2886 }
2887 assert(reg_chan);
2888
2889 /*
2890 * Create the buffers on the consumer side. This call populates the
2891 * ust app channel object with all streams and data object.
2892 */
2893 ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
2894 app->bits_per_long, reg_uid->registry->reg.ust);
2895 if (ret < 0) {
2896 ERR("Error creating UST channel \"%s\" on the consumer daemon",
2897 ua_chan->name);
2898
2899 /*
2900 * Let's remove the previously created buffer registry channel so
2901 * it's not visible anymore in the session registry.
2902 */
2903 ust_registry_channel_del_free(reg_uid->registry->reg.ust,
2904 ua_chan->tracing_channel_id, false);
2905 buffer_reg_channel_remove(reg_uid->registry, reg_chan);
2906 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2907 goto error;
2908 }
2909
2910 /*
2911 * Setup the streams and add it to the session registry.
2912 */
2913 ret = setup_buffer_reg_channel(reg_uid->registry,
2914 ua_chan, reg_chan, app);
2915 if (ret < 0) {
2916 ERR("Error setting up UST channel \"%s\"",
2917 ua_chan->name);
2918 goto error;
2919 }
2920 created = true;
2921 }
2922
2923 if (created) {
2924 enum lttng_error_code cmd_ret;
2925 struct ltt_session *session;
2926 uint64_t chan_reg_key;
2927 struct ust_registry_channel *chan_reg;
2928
2929 chan_reg_key = ua_chan->tracing_channel_id;
2930
2931 pthread_mutex_lock(&reg_uid->registry->reg.ust->lock);
2932 chan_reg = ust_registry_channel_find(reg_uid->registry->reg.ust,
2933 chan_reg_key);
2934 assert(chan_reg);
2935 chan_reg->consumer_key = ua_chan->key;
2936 chan_reg = NULL;
2937 pthread_mutex_unlock(&reg_uid->registry->reg.ust->lock);
2938
2939 session = session_find_by_id(ua_sess->tracing_id);
2940 assert(session);
2941
2942 cmd_ret = notification_thread_command_add_channel(
2943 notification_thread_handle, session->name,
2944 ua_sess->euid, ua_sess->egid,
2945 ua_chan->name,
2946 ua_chan->key,
2947 LTTNG_DOMAIN_UST,
2948 ua_chan->attr.subbuf_size * ua_chan->attr.num_subbuf);
2949 if (cmd_ret != LTTNG_OK) {
2950 ret = - (int) cmd_ret;
2951 ERR("Failed to add channel to notification thread");
2952 goto error;
2953 }
2954 }
2955
2956 /* Send buffers to the application. */
2957 ret = send_channel_uid_to_ust(reg_chan, app, ua_sess, ua_chan);
2958 if (ret < 0) {
2959 if (ret != -ENOTCONN) {
2960 ERR("Error sending channel to application");
2961 }
2962 goto error;
2963 }
2964
2965 error:
2966 return ret;
2967 }
2968
2969 /*
2970 * Create and send to the application the created buffers with per PID buffers.
2971 *
2972 * Called with UST app session lock held.
2973 *
2974 * Return 0 on success else a negative value.
2975 */
2976 static int create_channel_per_pid(struct ust_app *app,
2977 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2978 struct ust_app_channel *ua_chan)
2979 {
2980 int ret;
2981 struct ust_registry_session *registry;
2982 enum lttng_error_code cmd_ret;
2983 struct ltt_session *session;
2984 uint64_t chan_reg_key;
2985 struct ust_registry_channel *chan_reg;
2986
2987 assert(app);
2988 assert(usess);
2989 assert(ua_sess);
2990 assert(ua_chan);
2991
2992 DBG("UST app creating channel %s with per PID buffers", ua_chan->name);
2993
2994 rcu_read_lock();
2995
2996 registry = get_session_registry(ua_sess);
2997 /* The UST app session lock is held, registry shall not be null. */
2998 assert(registry);
2999
3000 /* Create and add a new channel registry to session. */
3001 ret = ust_registry_channel_add(registry, ua_chan->key);
3002 if (ret < 0) {
3003 ERR("Error creating the UST channel \"%s\" registry instance",
3004 ua_chan->name);
3005 goto error;
3006 }
3007
3008 /* Create and get channel on the consumer side. */
3009 ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
3010 app->bits_per_long, registry);
3011 if (ret < 0) {
3012 ERR("Error creating UST channel \"%s\" on the consumer daemon",
3013 ua_chan->name);
3014 goto error;
3015 }
3016
3017 ret = send_channel_pid_to_ust(app, ua_sess, ua_chan);
3018 if (ret < 0) {
3019 if (ret != -ENOTCONN) {
3020 ERR("Error sending channel to application");
3021 }
3022 goto error;
3023 }
3024
3025 session = session_find_by_id(ua_sess->tracing_id);
3026 assert(session);
3027
3028 chan_reg_key = ua_chan->key;
3029 pthread_mutex_lock(&registry->lock);
3030 chan_reg = ust_registry_channel_find(registry, chan_reg_key);
3031 assert(chan_reg);
3032 chan_reg->consumer_key = ua_chan->key;
3033 pthread_mutex_unlock(&registry->lock);
3034
3035 cmd_ret = notification_thread_command_add_channel(
3036 notification_thread_handle, session->name,
3037 ua_sess->euid, ua_sess->egid,
3038 ua_chan->name,
3039 ua_chan->key,
3040 LTTNG_DOMAIN_UST,
3041 ua_chan->attr.subbuf_size * ua_chan->attr.num_subbuf);
3042 if (cmd_ret != LTTNG_OK) {
3043 ret = - (int) cmd_ret;
3044 ERR("Failed to add channel to notification thread");
3045 goto error;
3046 }
3047
3048 error:
3049 rcu_read_unlock();
3050 return ret;
3051 }
3052
3053 /*
3054 * From an already allocated ust app channel, create the channel buffers if
3055 * need and send it to the application. This MUST be called with a RCU read
3056 * side lock acquired.
3057 *
3058 * Called with UST app session lock held.
3059 *
3060 * Return 0 on success or else a negative value. Returns -ENOTCONN if
3061 * the application exited concurrently.
3062 */
3063 static int do_create_channel(struct ust_app *app,
3064 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
3065 struct ust_app_channel *ua_chan)
3066 {
3067 int ret;
3068
3069 assert(app);
3070 assert(usess);
3071 assert(ua_sess);
3072 assert(ua_chan);
3073
3074 /* Handle buffer type before sending the channel to the application. */
3075 switch (usess->buffer_type) {
3076 case LTTNG_BUFFER_PER_UID:
3077 {
3078 ret = create_channel_per_uid(app, usess, ua_sess, ua_chan);
3079 if (ret < 0) {
3080 goto error;
3081 }
3082 break;
3083 }
3084 case LTTNG_BUFFER_PER_PID:
3085 {
3086 ret = create_channel_per_pid(app, usess, ua_sess, ua_chan);
3087 if (ret < 0) {
3088 goto error;
3089 }
3090 break;
3091 }
3092 default:
3093 assert(0);
3094 ret = -EINVAL;
3095 goto error;
3096 }
3097
3098 /* Initialize ust objd object using the received handle and add it. */
3099 lttng_ht_node_init_ulong(&ua_chan->ust_objd_node, ua_chan->handle);
3100 lttng_ht_add_unique_ulong(app->ust_objd, &ua_chan->ust_objd_node);
3101
3102 /* If channel is not enabled, disable it on the tracer */
3103 if (!ua_chan->enabled) {
3104 ret = disable_ust_channel(app, ua_sess, ua_chan);
3105 if (ret < 0) {
3106 goto error;
3107 }
3108 }
3109
3110 error:
3111 return ret;
3112 }
3113
3114 /*
3115 * Create UST app channel and create it on the tracer. Set ua_chanp of the
3116 * newly created channel if not NULL.
3117 *
3118 * Called with UST app session lock and RCU read-side lock held.
3119 *
3120 * Return 0 on success or else a negative value. Returns -ENOTCONN if
3121 * the application exited concurrently.
3122 */
3123 static int create_ust_app_channel(struct ust_app_session *ua_sess,
3124 struct ltt_ust_channel *uchan, struct ust_app *app,
3125 enum lttng_ust_chan_type type, struct ltt_ust_session *usess,
3126 struct ust_app_channel **ua_chanp)
3127 {
3128 int ret = 0;
3129 struct lttng_ht_iter iter;
3130 struct lttng_ht_node_str *ua_chan_node;
3131 struct ust_app_channel *ua_chan;
3132
3133 /* Lookup channel in the ust app session */
3134 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
3135 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
3136 if (ua_chan_node != NULL) {
3137 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
3138 goto end;
3139 }
3140
3141 ua_chan = alloc_ust_app_channel(uchan->name, ua_sess, &uchan->attr);
3142 if (ua_chan == NULL) {
3143 /* Only malloc can fail here */
3144 ret = -ENOMEM;
3145 goto error_alloc;
3146 }
3147 shadow_copy_channel(ua_chan, uchan);
3148
3149 /* Set channel type. */
3150 ua_chan->attr.type = type;
3151
3152 ret = do_create_channel(app, usess, ua_sess, ua_chan);
3153 if (ret < 0) {
3154 goto error;
3155 }
3156
3157 DBG2("UST app create channel %s for PID %d completed", ua_chan->name,
3158 app->pid);
3159
3160 /* Only add the channel if successful on the tracer side. */
3161 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
3162 end:
3163 if (ua_chanp) {
3164 *ua_chanp = ua_chan;
3165 }
3166
3167 /* Everything went well. */
3168 return 0;
3169
3170 error:
3171 delete_ust_app_channel(ua_chan->is_sent ? app->sock : -1, ua_chan, app);
3172 error_alloc:
3173 return ret;
3174 }
3175
3176 /*
3177 * Create UST app event and create it on the tracer side.
3178 *
3179 * Called with ust app session mutex held.
3180 */
3181 static
3182 int create_ust_app_event(struct ust_app_session *ua_sess,
3183 struct ust_app_channel *ua_chan, struct ltt_ust_event *uevent,
3184 struct ust_app *app)
3185 {
3186 int ret = 0;
3187 struct ust_app_event *ua_event;
3188
3189 /* Get event node */
3190 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
3191 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
3192 if (ua_event != NULL) {
3193 ret = -EEXIST;
3194 goto end;
3195 }
3196
3197 /* Does not exist so create one */
3198 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
3199 if (ua_event == NULL) {
3200 /* Only malloc can failed so something is really wrong */
3201 ret = -ENOMEM;
3202 goto end;
3203 }
3204 shadow_copy_event(ua_event, uevent);
3205
3206 /* Create it on the tracer side */
3207 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
3208 if (ret < 0) {
3209 /* Not found previously means that it does not exist on the tracer */
3210 assert(ret != -LTTNG_UST_ERR_EXIST);
3211 goto error;
3212 }
3213
3214 add_unique_ust_app_event(ua_chan, ua_event);
3215
3216 DBG2("UST app create event %s for PID %d completed", ua_event->name,
3217 app->pid);
3218
3219 end:
3220 return ret;
3221
3222 error:
3223 /* Valid. Calling here is already in a read side lock */
3224 delete_ust_app_event(-1, ua_event, app);
3225 return ret;
3226 }
3227
3228 /*
3229 * Create UST metadata and open it on the tracer side.
3230 *
3231 * Called with UST app session lock held and RCU read side lock.
3232 */
3233 static int create_ust_app_metadata(struct ust_app_session *ua_sess,
3234 struct ust_app *app, struct consumer_output *consumer)
3235 {
3236 int ret = 0;
3237 struct ust_app_channel *metadata;
3238 struct consumer_socket *socket;
3239 struct ust_registry_session *registry;
3240
3241 assert(ua_sess);
3242 assert(app);
3243 assert(consumer);
3244
3245 registry = get_session_registry(ua_sess);
3246 /* The UST app session is held registry shall not be null. */
3247 assert(registry);
3248
3249 pthread_mutex_lock(&registry->lock);
3250
3251 /* Metadata already exists for this registry or it was closed previously */
3252 if (registry->metadata_key || registry->metadata_closed) {
3253 ret = 0;
3254 goto error;
3255 }
3256
3257 /* Allocate UST metadata */
3258 metadata = alloc_ust_app_channel(DEFAULT_METADATA_NAME, ua_sess, NULL);
3259 if (!metadata) {
3260 /* malloc() failed */
3261 ret = -ENOMEM;
3262 goto error;
3263 }
3264
3265 memcpy(&metadata->attr, &ua_sess->metadata_attr, sizeof(metadata->attr));
3266
3267 /* Need one fd for the channel. */
3268 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
3269 if (ret < 0) {
3270 ERR("Exhausted number of available FD upon create metadata");
3271 goto error;
3272 }
3273
3274 /* Get the right consumer socket for the application. */
3275 socket = consumer_find_socket_by_bitness(app->bits_per_long, consumer);
3276 if (!socket) {
3277 ret = -EINVAL;
3278 goto error_consumer;
3279 }
3280
3281 /*
3282 * Keep metadata key so we can identify it on the consumer side. Assign it
3283 * to the registry *before* we ask the consumer so we avoid the race of the
3284 * consumer requesting the metadata and the ask_channel call on our side
3285 * did not returned yet.
3286 */
3287 registry->metadata_key = metadata->key;
3288
3289 /*
3290 * Ask the metadata channel creation to the consumer. The metadata object
3291 * will be created by the consumer and kept their. However, the stream is
3292 * never added or monitored until we do a first push metadata to the
3293 * consumer.
3294 */
3295 ret = ust_consumer_ask_channel(ua_sess, metadata, consumer, socket,
3296 registry);
3297 if (ret < 0) {
3298 /* Nullify the metadata key so we don't try to close it later on. */
3299 registry->metadata_key = 0;
3300 goto error_consumer;
3301 }
3302
3303 /*
3304 * The setup command will make the metadata stream be sent to the relayd,
3305 * if applicable, and the thread managing the metadatas. This is important
3306 * because after this point, if an error occurs, the only way the stream
3307 * can be deleted is to be monitored in the consumer.
3308 */
3309 ret = consumer_setup_metadata(socket, metadata->key);
3310 if (ret < 0) {
3311 /* Nullify the metadata key so we don't try to close it later on. */
3312 registry->metadata_key = 0;
3313 goto error_consumer;
3314 }
3315
3316 DBG2("UST metadata with key %" PRIu64 " created for app pid %d",
3317 metadata->key, app->pid);
3318
3319 error_consumer:
3320 lttng_fd_put(LTTNG_FD_APPS, 1);
3321 delete_ust_app_channel(-1, metadata, app);
3322 error:
3323 pthread_mutex_unlock(&registry->lock);
3324 return ret;
3325 }
3326
3327 /*
3328 * Return ust app pointer or NULL if not found. RCU read side lock MUST be
3329 * acquired before calling this function.
3330 */
3331 struct ust_app *ust_app_find_by_pid(pid_t pid)
3332 {
3333 struct ust_app *app = NULL;
3334 struct lttng_ht_node_ulong *node;
3335 struct lttng_ht_iter iter;
3336
3337 lttng_ht_lookup(ust_app_ht, (void *)((unsigned long) pid), &iter);
3338 node = lttng_ht_iter_get_node_ulong(&iter);
3339 if (node == NULL) {
3340 DBG2("UST app no found with pid %d", pid);
3341 goto error;
3342 }
3343
3344 DBG2("Found UST app by pid %d", pid);
3345
3346 app = caa_container_of(node, struct ust_app, pid_n);
3347
3348 error:
3349 return app;
3350 }
3351
3352 /*
3353 * Allocate and init an UST app object using the registration information and
3354 * the command socket. This is called when the command socket connects to the
3355 * session daemon.
3356 *
3357 * The object is returned on success or else NULL.
3358 */
3359 struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock)
3360 {
3361 struct ust_app *lta = NULL;
3362
3363 assert(msg);
3364 assert(sock >= 0);
3365
3366 DBG3("UST app creating application for socket %d", sock);
3367
3368 if ((msg->bits_per_long == 64 &&
3369 (uatomic_read(&ust_consumerd64_fd) == -EINVAL))
3370 || (msg->bits_per_long == 32 &&
3371 (uatomic_read(&ust_consumerd32_fd) == -EINVAL))) {
3372 ERR("Registration failed: application \"%s\" (pid: %d) has "
3373 "%d-bit long, but no consumerd for this size is available.\n",
3374 msg->name, msg->pid, msg->bits_per_long);
3375 goto error;
3376 }
3377
3378 lta = zmalloc(sizeof(struct ust_app));
3379 if (lta == NULL) {
3380 PERROR("malloc");
3381 goto error;
3382 }
3383
3384 lta->ppid = msg->ppid;
3385 lta->uid = msg->uid;
3386 lta->gid = msg->gid;
3387
3388 lta->bits_per_long = msg->bits_per_long;
3389 lta->uint8_t_alignment = msg->uint8_t_alignment;
3390 lta->uint16_t_alignment = msg->uint16_t_alignment;
3391 lta->uint32_t_alignment = msg->uint32_t_alignment;
3392 lta->uint64_t_alignment = msg->uint64_t_alignment;
3393 lta->long_alignment = msg->long_alignment;
3394 lta->byte_order = msg->byte_order;
3395
3396 lta->v_major = msg->major;
3397 lta->v_minor = msg->minor;
3398 lta->sessions = lttng_ht_new(0, LTTNG_HT_TYPE_U64);
3399 lta->ust_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
3400 lta->ust_sessions_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
3401 lta->notify_sock = -1;
3402
3403 /* Copy name and make sure it's NULL terminated. */
3404 strncpy(lta->name, msg->name, sizeof(lta->name));
3405 lta->name[UST_APP_PROCNAME_LEN] = '\0';
3406
3407 /*
3408 * Before this can be called, when receiving the registration information,
3409 * the application compatibility is checked. So, at this point, the
3410 * application can work with this session daemon.
3411 */
3412 lta->compatible = 1;
3413
3414 lta->pid = msg->pid;
3415 lttng_ht_node_init_ulong(&lta->pid_n, (unsigned long) lta->pid);
3416 lta->sock = sock;
3417 pthread_mutex_init(&lta->sock_lock, NULL);
3418 lttng_ht_node_init_ulong(&lta->sock_n, (unsigned long) lta->sock);
3419
3420 CDS_INIT_LIST_HEAD(&lta->teardown_head);
3421 error:
3422 return lta;
3423 }
3424
3425 /*
3426 * For a given application object, add it to every hash table.
3427 */
3428 void ust_app_add(struct ust_app *app)
3429 {
3430 assert(app);
3431 assert(app->notify_sock >= 0);
3432
3433 rcu_read_lock();
3434
3435 /*
3436 * On a re-registration, we want to kick out the previous registration of
3437 * that pid
3438 */
3439 lttng_ht_add_replace_ulong(ust_app_ht, &app->pid_n);
3440
3441 /*
3442 * The socket _should_ be unique until _we_ call close. So, a add_unique
3443 * for the ust_app_ht_by_sock is used which asserts fail if the entry was
3444 * already in the table.
3445 */
3446 lttng_ht_add_unique_ulong(ust_app_ht_by_sock, &app->sock_n);
3447
3448 /* Add application to the notify socket hash table. */
3449 lttng_ht_node_init_ulong(&app->notify_sock_n, app->notify_sock);
3450 lttng_ht_add_unique_ulong(ust_app_ht_by_notify_sock, &app->notify_sock_n);
3451
3452 DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s "
3453 "notify_sock:%d (version %d.%d)", app->pid, app->ppid, app->uid,
3454 app->gid, app->sock, app->name, app->notify_sock, app->v_major,
3455 app->v_minor);
3456
3457 rcu_read_unlock();
3458 }
3459
3460 /*
3461 * Set the application version into the object.
3462 *
3463 * Return 0 on success else a negative value either an errno code or a
3464 * LTTng-UST error code.
3465 */
3466 int ust_app_version(struct ust_app *app)
3467 {
3468 int ret;
3469
3470 assert(app);
3471
3472 pthread_mutex_lock(&app->sock_lock);
3473 ret = ustctl_tracer_version(app->sock, &app->version);
3474 pthread_mutex_unlock(&app->sock_lock);
3475 if (ret < 0) {
3476 if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
3477 ERR("UST app %d version failed with ret %d", app->sock, ret);
3478 } else {
3479 DBG3("UST app %d version failed. Application is dead", app->sock);
3480 }
3481 }
3482
3483 return ret;
3484 }
3485
3486 /*
3487 * Unregister app by removing it from the global traceable app list and freeing
3488 * the data struct.
3489 *
3490 * The socket is already closed at this point so no close to sock.
3491 */
3492 void ust_app_unregister(int sock)
3493 {
3494 struct ust_app *lta;
3495 struct lttng_ht_node_ulong *node;
3496 struct lttng_ht_iter ust_app_sock_iter;
3497 struct lttng_ht_iter iter;
3498 struct ust_app_session *ua_sess;
3499 int ret;
3500
3501 rcu_read_lock();
3502
3503 /* Get the node reference for a call_rcu */
3504 lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &ust_app_sock_iter);
3505 node = lttng_ht_iter_get_node_ulong(&ust_app_sock_iter);
3506 assert(node);
3507
3508 lta = caa_container_of(node, struct ust_app, sock_n);
3509 DBG("PID %d unregistering with sock %d", lta->pid, sock);
3510
3511 /*
3512 * For per-PID buffers, perform "push metadata" and flush all
3513 * application streams before removing app from hash tables,
3514 * ensuring proper behavior of data_pending check.
3515 * Remove sessions so they are not visible during deletion.
3516 */
3517 cds_lfht_for_each_entry(lta->sessions->ht, &iter.iter, ua_sess,
3518 node.node) {
3519 struct ust_registry_session *registry;
3520
3521 ret = lttng_ht_del(lta->sessions, &iter);
3522 if (ret) {
3523 /* The session was already removed so scheduled for teardown. */
3524 continue;
3525 }
3526
3527 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) {
3528 (void) ust_app_flush_app_session(lta, ua_sess);
3529 }
3530
3531 /*
3532 * Add session to list for teardown. This is safe since at this point we
3533 * are the only one using this list.
3534 */
3535 pthread_mutex_lock(&ua_sess->lock);
3536
3537 if (ua_sess->deleted) {
3538 pthread_mutex_unlock(&ua_sess->lock);
3539 continue;
3540 }
3541
3542 /*
3543 * Normally, this is done in the delete session process which is
3544 * executed in the call rcu below. However, upon registration we can't
3545 * afford to wait for the grace period before pushing data or else the
3546 * data pending feature can race between the unregistration and stop
3547 * command where the data pending command is sent *before* the grace
3548 * period ended.
3549 *
3550 * The close metadata below nullifies the metadata pointer in the
3551 * session so the delete session will NOT push/close a second time.
3552 */
3553 registry = get_session_registry(ua_sess);
3554 if (registry) {
3555 /* Push metadata for application before freeing the application. */
3556 (void) push_metadata(registry, ua_sess->consumer);
3557
3558 /*
3559 * Don't ask to close metadata for global per UID buffers. Close
3560 * metadata only on destroy trace session in this case. Also, the
3561 * previous push metadata could have flag the metadata registry to
3562 * close so don't send a close command if closed.
3563 */
3564 if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID) {
3565 /* And ask to close it for this session registry. */
3566 (void) close_metadata(registry, ua_sess->consumer);
3567 }
3568 }
3569 cds_list_add(&ua_sess->teardown_node, &lta->teardown_head);
3570
3571 pthread_mutex_unlock(&ua_sess->lock);
3572 }
3573
3574 /* Remove application from PID hash table */
3575 ret = lttng_ht_del(ust_app_ht_by_sock, &ust_app_sock_iter);
3576 assert(!ret);
3577
3578 /*
3579 * Remove application from notify hash table. The thread handling the
3580 * notify socket could have deleted the node so ignore on error because
3581 * either way it's valid. The close of that socket is handled by the
3582 * apps_notify_thread.
3583 */
3584 iter.iter.node = &lta->notify_sock_n.node;
3585 (void) lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
3586
3587 /*
3588 * Ignore return value since the node might have been removed before by an
3589 * add replace during app registration because the PID can be reassigned by
3590 * the OS.
3591 */
3592 iter.iter.node = &lta->pid_n.node;
3593 ret = lttng_ht_del(ust_app_ht, &iter);
3594 if (ret) {
3595 DBG3("Unregister app by PID %d failed. This can happen on pid reuse",
3596 lta->pid);
3597 }
3598
3599 /* Free memory */
3600 call_rcu(&lta->pid_n.head, delete_ust_app_rcu);
3601
3602 rcu_read_unlock();
3603 return;
3604 }
3605
3606 /*
3607 * Fill events array with all events name of all registered apps.
3608 */
3609 int ust_app_list_events(struct lttng_event **events)
3610 {
3611 int ret, handle;
3612 size_t nbmem, count = 0;
3613 struct lttng_ht_iter iter;
3614 struct ust_app *app;
3615 struct lttng_event *tmp_event;
3616
3617 nbmem = UST_APP_EVENT_LIST_SIZE;
3618 tmp_event = zmalloc(nbmem * sizeof(struct lttng_event));
3619 if (tmp_event == NULL) {
3620 PERROR("zmalloc ust app events");
3621 ret = -ENOMEM;
3622 goto error;
3623 }
3624
3625 rcu_read_lock();
3626
3627 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
3628 struct lttng_ust_tracepoint_iter uiter;
3629
3630 health_code_update();
3631
3632 if (!app->compatible) {
3633 /*
3634 * TODO: In time, we should notice the caller of this error by
3635 * telling him that this is a version error.
3636 */
3637 continue;
3638 }
3639 pthread_mutex_lock(&app->sock_lock);
3640 handle = ustctl_tracepoint_list(app->sock);
3641 if (handle < 0) {
3642 if (handle != -EPIPE && handle != -LTTNG_UST_ERR_EXITING) {
3643 ERR("UST app list events getting handle failed for app pid %d",
3644 app->pid);
3645 }
3646 pthread_mutex_unlock(&app->sock_lock);
3647 continue;
3648 }
3649
3650 while ((ret = ustctl_tracepoint_list_get(app->sock, handle,
3651 &uiter)) != -LTTNG_UST_ERR_NOENT) {
3652 /* Handle ustctl error. */
3653 if (ret < 0) {
3654 int release_ret;
3655
3656 if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
3657 ERR("UST app tp list get failed for app %d with ret %d",
3658 app->sock, ret);
3659 } else {
3660 DBG3("UST app tp list get failed. Application is dead");
3661 /*
3662 * This is normal behavior, an application can die during the
3663 * creation process. Don't report an error so the execution can
3664 * continue normally. Continue normal execution.
3665 */
3666 break;
3667 }
3668 free(tmp_event);
3669 release_ret = ustctl_release_handle(app->sock, handle);
3670 if (release_ret < 0 &&
3671 release_ret != -LTTNG_UST_ERR_EXITING &&
3672 release_ret != -EPIPE) {
3673 ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret);
3674 }
3675 pthread_mutex_unlock(&app->sock_lock);
3676 goto rcu_error;
3677 }
3678
3679 health_code_update();
3680 if (count >= nbmem) {
3681 /* In case the realloc fails, we free the memory */
3682 struct lttng_event *new_tmp_event;
3683 size_t new_nbmem;
3684
3685 new_nbmem = nbmem << 1;
3686 DBG2("Reallocating event list from %zu to %zu entries",
3687 nbmem, new_nbmem);
3688 new_tmp_event = realloc(tmp_event,
3689 new_nbmem * sizeof(struct lttng_event));
3690 if (new_tmp_event == NULL) {
3691 int release_ret;
3692
3693 PERROR("realloc ust app events");
3694 free(tmp_event);
3695 ret = -ENOMEM;
3696 release_ret = ustctl_release_handle(app->sock, handle);
3697 if (release_ret < 0 &&
3698 release_ret != -LTTNG_UST_ERR_EXITING &&
3699 release_ret != -EPIPE) {
3700 ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret);
3701 }
3702 pthread_mutex_unlock(&app->sock_lock);
3703 goto rcu_error;
3704 }
3705 /* Zero the new memory */
3706 memset(new_tmp_event + nbmem, 0,
3707 (new_nbmem - nbmem) * sizeof(struct lttng_event));
3708 nbmem = new_nbmem;
3709 tmp_event = new_tmp_event;
3710 }
3711 memcpy(tmp_event[count].name, uiter.name, LTTNG_UST_SYM_NAME_LEN);
3712 tmp_event[count].loglevel = uiter.loglevel;
3713 tmp_event[count].type = (enum lttng_event_type) LTTNG_UST_TRACEPOINT;
3714 tmp_event[count].pid = app->pid;
3715 tmp_event[count].enabled = -1;
3716 count++;
3717 }
3718 ret = ustctl_release_handle(app->sock, handle);
3719 pthread_mutex_unlock(&app->sock_lock);
3720 if (ret < 0 && ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
3721 ERR("Error releasing app handle for app %d with ret %d", app->sock, ret);
3722 }
3723 }
3724
3725 ret = count;
3726 *events = tmp_event;
3727
3728 DBG2("UST app list events done (%zu events)", count);
3729
3730 rcu_error:
3731 rcu_read_unlock();
3732 error:
3733 health_code_update();
3734 return ret;
3735 }
3736
3737 /*
3738 * Fill events array with all events name of all registered apps.
3739 */
3740 int ust_app_list_event_fields(struct lttng_event_field **fields)
3741 {
3742 int ret, handle;
3743 size_t nbmem, count = 0;
3744 struct lttng_ht_iter iter;
3745 struct ust_app *app;
3746 struct lttng_event_field *tmp_event;
3747
3748 nbmem = UST_APP_EVENT_LIST_SIZE;
3749 tmp_event = zmalloc(nbmem * sizeof(struct lttng_event_field));
3750 if (tmp_event == NULL) {
3751 PERROR("zmalloc ust app event fields");
3752 ret = -ENOMEM;
3753 goto error;
3754 }
3755
3756 rcu_read_lock();
3757
3758 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
3759 struct lttng_ust_field_iter uiter;
3760
3761 health_code_update();
3762
3763 if (!app->compatible) {
3764 /*
3765 * TODO: In time, we should notice the caller of this error by
3766 * telling him that this is a version error.
3767 */
3768 continue;
3769 }
3770 pthread_mutex_lock(&app->sock_lock);
3771 handle = ustctl_tracepoint_field_list(app->sock);
3772 if (handle < 0) {
3773 if (handle != -EPIPE && handle != -LTTNG_UST_ERR_EXITING) {
3774 ERR("UST app list field getting handle failed for app pid %d",
3775 app->pid);
3776 }
3777 pthread_mutex_unlock(&app->sock_lock);
3778 continue;
3779 }
3780
3781 while ((ret = ustctl_tracepoint_field_list_get(app->sock, handle,
3782 &uiter)) != -LTTNG_UST_ERR_NOENT) {
3783 /* Handle ustctl error. */
3784 if (ret < 0) {
3785 int release_ret;
3786
3787 if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
3788 ERR("UST app tp list field failed for app %d with ret %d",
3789 app->sock, ret);
3790 } else {
3791 DBG3("UST app tp list field failed. Application is dead");
3792 /*
3793 * This is normal behavior, an application can die during the
3794 * creation process. Don't report an error so the execution can
3795 * continue normally. Reset list and count for next app.
3796 */
3797 break;
3798 }
3799 free(tmp_event);
3800 release_ret = ustctl_release_handle(app->sock, handle);
3801 pthread_mutex_unlock(&app->sock_lock);
3802 if (release_ret < 0 &&
3803 release_ret != -LTTNG_UST_ERR_EXITING &&
3804 release_ret != -EPIPE) {
3805 ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret);
3806 }
3807 goto rcu_error;
3808 }
3809
3810 health_code_update();
3811 if (count >= nbmem) {
3812 /* In case the realloc fails, we free the memory */
3813 struct lttng_event_field *new_tmp_event;
3814 size_t new_nbmem;
3815
3816 new_nbmem = nbmem << 1;
3817 DBG2("Reallocating event field list from %zu to %zu entries",
3818 nbmem, new_nbmem);
3819 new_tmp_event = realloc(tmp_event,
3820 new_nbmem * sizeof(struct lttng_event_field));
3821 if (new_tmp_event == NULL) {
3822 int release_ret;
3823
3824 PERROR("realloc ust app event fields");
3825 free(tmp_event);
3826 ret = -ENOMEM;
3827 release_ret = ustctl_release_handle(app->sock, handle);
3828 pthread_mutex_unlock(&app->sock_lock);
3829 if (release_ret &&
3830 release_ret != -LTTNG_UST_ERR_EXITING &&
3831 release_ret != -EPIPE) {
3832 ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret);
3833 }
3834 goto rcu_error;
3835 }
3836 /* Zero the new memory */
3837 memset(new_tmp_event + nbmem, 0,
3838 (new_nbmem - nbmem) * sizeof(struct lttng_event_field));
3839 nbmem = new_nbmem;
3840 tmp_event = new_tmp_event;
3841 }
3842
3843 memcpy(tmp_event[count].field_name, uiter.field_name, LTTNG_UST_SYM_NAME_LEN);
3844 /* Mapping between these enums matches 1 to 1. */
3845 tmp_event[count].type = (enum lttng_event_field_type) uiter.type;
3846 tmp_event[count].nowrite = uiter.nowrite;
3847
3848 memcpy(tmp_event[count].event.name, uiter.event_name, LTTNG_UST_SYM_NAME_LEN);
3849 tmp_event[count].event.loglevel = uiter.loglevel;
3850 tmp_event[count].event.type = LTTNG_EVENT_TRACEPOINT;
3851 tmp_event[count].event.pid = app->pid;
3852 tmp_event[count].event.enabled = -1;
3853 count++;
3854 }
3855 ret = ustctl_release_handle(app->sock, handle);
3856 pthread_mutex_unlock(&app->sock_lock);
3857 if (ret < 0 &&
3858 ret != -LTTNG_UST_ERR_EXITING &&
3859 ret != -EPIPE) {
3860 ERR("Error releasing app handle for app %d with ret %d", app->sock, ret);
3861 }
3862 }
3863
3864 ret = count;
3865 *fields = tmp_event;
3866
3867 DBG2("UST app list event fields done (%zu events)", count);
3868
3869 rcu_error:
3870 rcu_read_unlock();
3871 error:
3872 health_code_update();
3873 return ret;
3874 }
3875
3876 /*
3877 * Free and clean all traceable apps of the global list.
3878 *
3879 * Should _NOT_ be called with RCU read-side lock held.
3880 */
3881 void ust_app_clean_list(void)
3882 {
3883 int ret;
3884 struct ust_app *app;
3885 struct lttng_ht_iter iter;
3886
3887 DBG2("UST app cleaning registered apps hash table");
3888
3889 rcu_read_lock();
3890
3891 if (ust_app_ht) {
3892 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
3893 ret = lttng_ht_del(ust_app_ht, &iter);
3894 assert(!ret);
3895 call_rcu(&app->pid_n.head, delete_ust_app_rcu);
3896 }
3897 }
3898
3899 /* Cleanup socket hash table */
3900 if (ust_app_ht_by_sock) {
3901 cds_lfht_for_each_entry(ust_app_ht_by_sock->ht, &iter.iter, app,
3902 sock_n.node) {
3903 ret = lttng_ht_del(ust_app_ht_by_sock, &iter);
3904 assert(!ret);
3905 }
3906 }
3907
3908 /* Cleanup notify socket hash table */
3909 if (ust_app_ht_by_notify_sock) {
3910 cds_lfht_for_each_entry(ust_app_ht_by_notify_sock->ht, &iter.iter, app,
3911 notify_sock_n.node) {
3912 ret = lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
3913 assert(!ret);
3914 }
3915 }
3916 rcu_read_unlock();
3917
3918 /* Destroy is done only when the ht is empty */
3919 if (ust_app_ht) {
3920 ht_cleanup_push(ust_app_ht);
3921 }
3922 if (ust_app_ht_by_sock) {
3923 ht_cleanup_push(ust_app_ht_by_sock);
3924 }
3925 if (ust_app_ht_by_notify_sock) {
3926 ht_cleanup_push(ust_app_ht_by_notify_sock);
3927 }
3928 }
3929
3930 /*
3931 * Init UST app hash table.
3932 */
3933 int ust_app_ht_alloc(void)
3934 {
3935 ust_app_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
3936 if (!ust_app_ht) {
3937 return -1;
3938 }
3939 ust_app_ht_by_sock = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
3940 if (!ust_app_ht_by_sock) {
3941 return -1;
3942 }
3943 ust_app_ht_by_notify_sock = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
3944 if (!ust_app_ht_by_notify_sock) {
3945 return -1;
3946 }
3947 return 0;
3948 }
3949
3950 /*
3951 * For a specific UST session, disable the channel for all registered apps.
3952 */
3953 int ust_app_disable_channel_glb(struct ltt_ust_session *usess,
3954 struct ltt_ust_channel *uchan)
3955 {
3956 int ret = 0;
3957 struct lttng_ht_iter iter;
3958 struct lttng_ht_node_str *ua_chan_node;
3959 struct ust_app *app;
3960 struct ust_app_session *ua_sess;
3961 struct ust_app_channel *ua_chan;
3962
3963 if (usess == NULL || uchan == NULL) {
3964 ERR("Disabling UST global channel with NULL values");
3965 ret = -1;
3966 goto error;
3967 }
3968
3969 DBG2("UST app disabling channel %s from global domain for session id %" PRIu64,
3970 uchan->name, usess->id);
3971
3972 rcu_read_lock();
3973
3974 /* For every registered applications */
3975 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
3976 struct lttng_ht_iter uiter;
3977 if (!app->compatible) {
3978 /*
3979 * TODO: In time, we should notice the caller of this error by
3980 * telling him that this is a version error.
3981 */
3982 continue;
3983 }
3984 ua_sess = lookup_session_by_app(usess, app);
3985 if (ua_sess == NULL) {
3986 continue;
3987 }
3988
3989 /* Get channel */
3990 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
3991 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
3992 /* If the session if found for the app, the channel must be there */
3993 assert(ua_chan_node);
3994
3995 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
3996 /* The channel must not be already disabled */
3997 assert(ua_chan->enabled == 1);
3998
3999 /* Disable channel onto application */
4000 ret = disable_ust_app_channel(ua_sess, ua_chan, app);
4001 if (ret < 0) {
4002 /* XXX: We might want to report this error at some point... */
4003 continue;
4004 }
4005 }
4006
4007 rcu_read_unlock();
4008
4009 error:
4010 return ret;
4011 }
4012
4013 /*
4014 * For a specific UST session, enable the channel for all registered apps.
4015 */
4016 int ust_app_enable_channel_glb(struct ltt_ust_session *usess,
4017 struct ltt_ust_channel *uchan)
4018 {
4019 int ret = 0;
4020 struct lttng_ht_iter iter;
4021 struct ust_app *app;
4022 struct ust_app_session *ua_sess;
4023
4024 if (usess == NULL || uchan == NULL) {
4025 ERR("Adding UST global channel to NULL values");
4026 ret = -1;
4027 goto error;
4028 }
4029
4030 DBG2("UST app enabling channel %s to global domain for session id %" PRIu64,
4031 uchan->name, usess->id);
4032
4033 rcu_read_lock();
4034
4035 /* For every registered applications */
4036 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4037 if (!app->compatible) {
4038 /*
4039 * TODO: In time, we should notice the caller of this error by
4040 * telling him that this is a version error.
4041 */
4042 continue;
4043 }
4044 ua_sess = lookup_session_by_app(usess, app);
4045 if (ua_sess == NULL) {
4046 continue;
4047 }
4048
4049 /* Enable channel onto application */
4050 ret = enable_ust_app_channel(ua_sess, uchan, app);
4051 if (ret < 0) {
4052 /* XXX: We might want to report this error at some point... */
4053 continue;
4054 }
4055 }
4056
4057 rcu_read_unlock();
4058
4059 error:
4060 return ret;
4061 }
4062
4063 /*
4064 * Disable an event in a channel and for a specific session.
4065 */
4066 int ust_app_disable_event_glb(struct ltt_ust_session *usess,
4067 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
4068 {
4069 int ret = 0;
4070 struct lttng_ht_iter iter, uiter;
4071 struct lttng_ht_node_str *ua_chan_node;
4072 struct ust_app *app;
4073 struct ust_app_session *ua_sess;
4074 struct ust_app_channel *ua_chan;
4075 struct ust_app_event *ua_event;
4076
4077 DBG("UST app disabling event %s for all apps in channel "
4078 "%s for session id %" PRIu64,
4079 uevent->attr.name, uchan->name, usess->id);
4080
4081 rcu_read_lock();
4082
4083 /* For all registered applications */
4084 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4085 if (!app->compatible) {
4086 /*
4087 * TODO: In time, we should notice the caller of this error by
4088 * telling him that this is a version error.
4089 */
4090 continue;
4091 }
4092 ua_sess = lookup_session_by_app(usess, app);
4093 if (ua_sess == NULL) {
4094 /* Next app */
4095 continue;
4096 }
4097
4098 /* Lookup channel in the ust app session */
4099 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
4100 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
4101 if (ua_chan_node == NULL) {
4102 DBG2("Channel %s not found in session id %" PRIu64 " for app pid %d."
4103 "Skipping", uchan->name, usess->id, app->pid);
4104 continue;
4105 }
4106 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
4107
4108 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
4109 uevent->filter, uevent->attr.loglevel,
4110 uevent->exclusion);
4111 if (ua_event == NULL) {
4112 DBG2("Event %s not found in channel %s for app pid %d."
4113 "Skipping", uevent->attr.name, uchan->name, app->pid);
4114 continue;
4115 }
4116
4117 ret = disable_ust_app_event(ua_sess, ua_event, app);
4118 if (ret < 0) {
4119 /* XXX: Report error someday... */
4120 continue;
4121 }
4122 }
4123
4124 rcu_read_unlock();
4125
4126 return ret;
4127 }
4128
4129 /*
4130 * For a specific UST session, create the channel for all registered apps.
4131 */
4132 int ust_app_create_channel_glb(struct ltt_ust_session *usess,
4133 struct ltt_ust_channel *uchan)
4134 {
4135 int ret = 0, created;
4136 struct lttng_ht_iter iter;
4137 struct ust_app *app;
4138 struct ust_app_session *ua_sess = NULL;
4139
4140 /* Very wrong code flow */
4141 assert(usess);
4142 assert(uchan);
4143
4144 DBG2("UST app adding channel %s to UST domain for session id %" PRIu64,
4145 uchan->name, usess->id);
4146
4147 rcu_read_lock();
4148
4149 /* For every registered applications */
4150 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4151 if (!app->compatible) {
4152 /*
4153 * TODO: In time, we should notice the caller of this error by
4154 * telling him that this is a version error.
4155 */
4156 continue;
4157 }
4158 if (!trace_ust_pid_tracker_lookup(usess, app->pid)) {
4159 /* Skip. */
4160 continue;
4161 }
4162
4163 /*
4164 * Create session on the tracer side and add it to app session HT. Note
4165 * that if session exist, it will simply return a pointer to the ust
4166 * app session.
4167 */
4168 ret = find_or_create_ust_app_session(usess, app, &ua_sess, &created);
4169 if (ret < 0) {
4170 switch (ret) {
4171 case -ENOTCONN:
4172 /*
4173 * The application's socket is not valid. Either a bad socket
4174 * or a timeout on it. We can't inform the caller that for a
4175 * specific app, the session failed so lets continue here.
4176 */
4177 ret = 0; /* Not an error. */
4178 continue;
4179 case -ENOMEM:
4180 default:
4181 goto error_rcu_unlock;
4182 }
4183 }
4184 assert(ua_sess);
4185
4186 pthread_mutex_lock(&ua_sess->lock);
4187
4188 if (ua_sess->deleted) {
4189 pthread_mutex_unlock(&ua_sess->lock);
4190 continue;
4191 }
4192
4193 if (!strncmp(uchan->name, DEFAULT_METADATA_NAME,
4194 sizeof(uchan->name))) {
4195 copy_channel_attr_to_ustctl(&ua_sess->metadata_attr, &uchan->attr);
4196 ret = 0;
4197 } else {
4198 /* Create channel onto application. We don't need the chan ref. */
4199 ret = create_ust_app_channel(ua_sess, uchan, app,
4200 LTTNG_UST_CHAN_PER_CPU, usess, NULL);
4201 }
4202 pthread_mutex_unlock(&ua_sess->lock);
4203 if (ret < 0) {
4204 /* Cleanup the created session if it's the case. */
4205 if (created) {
4206 destroy_app_session(app, ua_sess);
4207 }
4208 switch (ret) {
4209 case -ENOTCONN:
4210 /*
4211 * The application's socket is not valid. Either a bad socket
4212 * or a timeout on it. We can't inform the caller that for a
4213 * specific app, the session failed so lets continue here.
4214 */
4215 ret = 0; /* Not an error. */
4216 continue;
4217 case -ENOMEM:
4218 default:
4219 goto error_rcu_unlock;
4220 }
4221 }
4222 }
4223
4224 error_rcu_unlock:
4225 rcu_read_unlock();
4226 return ret;
4227 }
4228
4229 /*
4230 * Enable event for a specific session and channel on the tracer.
4231 */
4232 int ust_app_enable_event_glb(struct ltt_ust_session *usess,
4233 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
4234 {
4235 int ret = 0;
4236 struct lttng_ht_iter iter, uiter;
4237 struct lttng_ht_node_str *ua_chan_node;
4238 struct ust_app *app;
4239 struct ust_app_session *ua_sess;
4240 struct ust_app_channel *ua_chan;
4241 struct ust_app_event *ua_event;
4242
4243 DBG("UST app enabling event %s for all apps for session id %" PRIu64,
4244 uevent->attr.name, usess->id);
4245
4246 /*
4247 * NOTE: At this point, this function is called only if the session and
4248 * channel passed are already created for all apps. and enabled on the
4249 * tracer also.
4250 */
4251
4252 rcu_read_lock();
4253
4254 /* For all registered applications */
4255 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4256 if (!app->compatible) {
4257 /*
4258 * TODO: In time, we should notice the caller of this error by
4259 * telling him that this is a version error.
4260 */
4261 continue;
4262 }
4263 ua_sess = lookup_session_by_app(usess, app);
4264 if (!ua_sess) {
4265 /* The application has problem or is probably dead. */
4266 continue;
4267 }
4268
4269 pthread_mutex_lock(&ua_sess->lock);
4270
4271 if (ua_sess->deleted) {
4272 pthread_mutex_unlock(&ua_sess->lock);
4273 continue;
4274 }
4275
4276 /* Lookup channel in the ust app session */
4277 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
4278 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
4279 /*
4280 * It is possible that the channel cannot be found is
4281 * the channel/event creation occurs concurrently with
4282 * an application exit.
4283 */
4284 if (!ua_chan_node) {
4285 pthread_mutex_unlock(&ua_sess->lock);
4286 continue;
4287 }
4288
4289 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
4290
4291 /* Get event node */
4292 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
4293 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
4294 if (ua_event == NULL) {
4295 DBG3("UST app enable event %s not found for app PID %d."
4296 "Skipping app", uevent->attr.name, app->pid);
4297 goto next_app;
4298 }
4299
4300 ret = enable_ust_app_event(ua_sess, ua_event, app);
4301 if (ret < 0) {
4302 pthread_mutex_unlock(&ua_sess->lock);
4303 goto error;
4304 }
4305 next_app:
4306 pthread_mutex_unlock(&ua_sess->lock);
4307 }
4308
4309 error:
4310 rcu_read_unlock();
4311 return ret;
4312 }
4313
4314 /*
4315 * For a specific existing UST session and UST channel, creates the event for
4316 * all registered apps.
4317 */
4318 int ust_app_create_event_glb(struct ltt_ust_session *usess,
4319 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
4320 {
4321 int ret = 0;
4322 struct lttng_ht_iter iter, uiter;
4323 struct lttng_ht_node_str *ua_chan_node;
4324 struct ust_app *app;
4325 struct ust_app_session *ua_sess;
4326 struct ust_app_channel *ua_chan;
4327
4328 DBG("UST app creating event %s for all apps for session id %" PRIu64,
4329 uevent->attr.name, usess->id);
4330
4331 rcu_read_lock();
4332
4333 /* For all registered applications */
4334 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4335 if (!app->compatible) {
4336 /*
4337 * TODO: In time, we should notice the caller of this error by
4338 * telling him that this is a version error.
4339 */
4340 continue;
4341 }
4342 ua_sess = lookup_session_by_app(usess, app);
4343 if (!ua_sess) {
4344 /* The application has problem or is probably dead. */
4345 continue;
4346 }
4347
4348 pthread_mutex_lock(&ua_sess->lock);
4349
4350 if (ua_sess->deleted) {
4351 pthread_mutex_unlock(&ua_sess->lock);
4352 continue;
4353 }
4354
4355 /* Lookup channel in the ust app session */
4356 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
4357 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
4358 /* If the channel is not found, there is a code flow error */
4359 assert(ua_chan_node);
4360
4361 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
4362
4363 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
4364 pthread_mutex_unlock(&ua_sess->lock);
4365 if (ret < 0) {
4366 if (ret != -LTTNG_UST_ERR_EXIST) {
4367 /* Possible value at this point: -ENOMEM. If so, we stop! */
4368 break;
4369 }
4370 DBG2("UST app event %s already exist on app PID %d",
4371 uevent->attr.name, app->pid);
4372 continue;
4373 }
4374 }
4375
4376 rcu_read_unlock();
4377
4378 return ret;
4379 }
4380
4381 /*
4382 * Start tracing for a specific UST session and app.
4383 *
4384 * Called with UST app session lock held.
4385 *
4386 */
4387 static
4388 int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
4389 {
4390 int ret = 0;
4391 struct ust_app_session *ua_sess;
4392
4393 DBG("Starting tracing for ust app pid %d", app->pid);
4394
4395 rcu_read_lock();
4396
4397 if (!app->compatible) {
4398 goto end;
4399 }
4400
4401 ua_sess = lookup_session_by_app(usess, app);
4402 if (ua_sess == NULL) {
4403 /* The session is in teardown process. Ignore and continue. */
4404 goto end;
4405 }
4406
4407 pthread_mutex_lock(&ua_sess->lock);
4408
4409 if (ua_sess->deleted) {
4410 pthread_mutex_unlock(&ua_sess->lock);
4411 goto end;
4412 }
4413
4414 /* Upon restart, we skip the setup, already done */
4415 if (ua_sess->started) {
4416 goto skip_setup;
4417 }
4418
4419 /* Create directories if consumer is LOCAL and has a path defined. */
4420 if (usess->consumer->type == CONSUMER_DST_LOCAL &&
4421 usess->consumer->dst.session_root_path[0] != '\0') {
4422 char *tmp_path;
4423
4424 tmp_path = zmalloc(LTTNG_PATH_MAX);
4425 if (!tmp_path) {
4426 ERR("Alloc tmp_path");
4427 goto error_unlock;
4428 }
4429 ret = snprintf(tmp_path, LTTNG_PATH_MAX, "%s%s%s",
4430 usess->consumer->dst.session_root_path,
4431 usess->consumer->chunk_path,
4432 usess->consumer->subdir);
4433 if (ret >= LTTNG_PATH_MAX) {
4434 ERR("Local destination path exceeds the maximal allowed length of %i bytes (needs %i bytes) with path = \"%s%s%s\"",
4435 LTTNG_PATH_MAX, ret,
4436 usess->consumer->dst.session_root_path,
4437 usess->consumer->chunk_path,
4438 usess->consumer->subdir);
4439 goto error_unlock;
4440 }
4441
4442 DBG("Creating directory path for local tracing: \"%s\"",
4443 tmp_path);
4444 ret = run_as_mkdir_recursive(tmp_path, S_IRWXU | S_IRWXG,
4445 ua_sess->euid, ua_sess->egid);
4446 free(tmp_path);
4447 if (ret < 0) {
4448 if (errno != EEXIST) {
4449 ERR("Trace directory creation error");
4450 goto error_unlock;
4451 }
4452 }
4453 }
4454
4455 /*
4456 * Create the metadata for the application. This returns gracefully if a
4457 * metadata was already set for the session.
4458 */
4459 ret = create_ust_app_metadata(ua_sess, app, usess->consumer);
4460 if (ret < 0) {
4461 goto error_unlock;
4462 }
4463
4464 health_code_update();
4465
4466 skip_setup:
4467 /* This start the UST tracing */
4468 pthread_mutex_lock(&app->sock_lock);
4469 ret = ustctl_start_session(app->sock, ua_sess->handle);
4470 pthread_mutex_unlock(&app->sock_lock);
4471 if (ret < 0) {
4472 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
4473 ERR("Error starting tracing for app pid: %d (ret: %d)",
4474 app->pid, ret);
4475 } else {
4476 DBG("UST app start session failed. Application is dead.");
4477 /*
4478 * This is normal behavior, an application can die during the
4479 * creation process. Don't report an error so the execution can
4480 * continue normally.
4481 */
4482 pthread_mutex_unlock(&ua_sess->lock);
4483 goto end;
4484 }
4485 goto error_unlock;
4486 }
4487
4488 /* Indicate that the session has been started once */
4489 ua_sess->started = 1;
4490
4491 pthread_mutex_unlock(&ua_sess->lock);
4492
4493 health_code_update();
4494
4495 /* Quiescent wait after starting trace */
4496 pthread_mutex_lock(&app->sock_lock);
4497 ret = ustctl_wait_quiescent(app->sock);
4498 pthread_mutex_unlock(&app->sock_lock);
4499 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
4500 ERR("UST app wait quiescent failed for app pid %d ret %d",
4501 app->pid, ret);
4502 }
4503
4504 end:
4505 rcu_read_unlock();
4506 health_code_update();
4507 return 0;
4508
4509 error_unlock:
4510 pthread_mutex_unlock(&ua_sess->lock);
4511 rcu_read_unlock();
4512 health_code_update();
4513 return -1;
4514 }
4515
4516 /*
4517 * Stop tracing for a specific UST session and app.
4518 */
4519 static
4520 int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
4521 {
4522 int ret = 0;
4523 struct ust_app_session *ua_sess;
4524 struct ust_registry_session *registry;
4525
4526 DBG("Stopping tracing for ust app pid %d", app->pid);
4527
4528 rcu_read_lock();
4529
4530 if (!app->compatible) {
4531 goto end_no_session;
4532 }
4533
4534 ua_sess = lookup_session_by_app(usess, app);
4535 if (ua_sess == NULL) {
4536 goto end_no_session;
4537 }
4538
4539 pthread_mutex_lock(&ua_sess->lock);
4540
4541 if (ua_sess->deleted) {
4542 pthread_mutex_unlock(&ua_sess->lock);
4543 goto end_no_session;
4544 }
4545
4546 /*
4547 * If started = 0, it means that stop trace has been called for a session
4548 * that was never started. It's possible since we can have a fail start
4549 * from either the application manager thread or the command thread. Simply
4550 * indicate that this is a stop error.
4551 */
4552 if (!ua_sess->started) {
4553 goto error_rcu_unlock;
4554 }
4555
4556 health_code_update();
4557
4558 /* This inhibits UST tracing */
4559 pthread_mutex_lock(&app->sock_lock);
4560 ret = ustctl_stop_session(app->sock, ua_sess->handle);
4561 pthread_mutex_unlock(&app->sock_lock);
4562 if (ret < 0) {
4563 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
4564 ERR("Error stopping tracing for app pid: %d (ret: %d)",
4565 app->pid, ret);
4566 } else {
4567 DBG("UST app stop session failed. Application is dead.");
4568 /*
4569 * This is normal behavior, an application can die during the
4570 * creation process. Don't report an error so the execution can
4571 * continue normally.
4572 */
4573 goto end_unlock;
4574 }
4575 goto error_rcu_unlock;
4576 }
4577
4578 health_code_update();
4579
4580 /* Quiescent wait after stopping trace */
4581 pthread_mutex_lock(&app->sock_lock);
4582 ret = ustctl_wait_quiescent(app->sock);
4583 pthread_mutex_unlock(&app->sock_lock);
4584 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
4585 ERR("UST app wait quiescent failed for app pid %d ret %d",
4586 app->pid, ret);
4587 }
4588
4589 health_code_update();
4590
4591 registry = get_session_registry(ua_sess);
4592
4593 /* The UST app session is held registry shall not be null. */
4594 assert(registry);
4595
4596 /* Push metadata for application before freeing the application. */
4597 (void) push_metadata(registry, ua_sess->consumer);
4598
4599 end_unlock:
4600 pthread_mutex_unlock(&ua_sess->lock);
4601 end_no_session:
4602 rcu_read_unlock();
4603 health_code_update();
4604 return 0;
4605
4606 error_rcu_unlock:
4607 pthread_mutex_unlock(&ua_sess->lock);
4608 rcu_read_unlock();
4609 health_code_update();
4610 return -1;
4611 }
4612
4613 static
4614 int ust_app_flush_app_session(struct ust_app *app,
4615 struct ust_app_session *ua_sess)
4616 {
4617 int ret, retval = 0;
4618 struct lttng_ht_iter iter;
4619 struct ust_app_channel *ua_chan;
4620 struct consumer_socket *socket;
4621
4622 DBG("Flushing app session buffers for ust app pid %d", app->pid);
4623
4624 rcu_read_lock();
4625
4626 if (!app->compatible) {
4627 goto end_not_compatible;
4628 }
4629
4630 pthread_mutex_lock(&ua_sess->lock);
4631
4632 if (ua_sess->deleted) {
4633 goto end_deleted;
4634 }
4635
4636 health_code_update();
4637
4638 /* Flushing buffers */
4639 socket = consumer_find_socket_by_bitness(app->bits_per_long,
4640 ua_sess->consumer);
4641
4642 /* Flush buffers and push metadata. */
4643 switch (ua_sess->buffer_type) {
4644 case LTTNG_BUFFER_PER_PID:
4645 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
4646 node.node) {
4647 health_code_update();
4648 ret = consumer_flush_channel(socket, ua_chan->key);
4649 if (ret) {
4650 ERR("Error flushing consumer channel");
4651 retval = -1;
4652 continue;
4653 }
4654 }
4655 break;
4656 case LTTNG_BUFFER_PER_UID:
4657 default:
4658 assert(0);
4659 break;
4660 }
4661
4662 health_code_update();
4663
4664 end_deleted:
4665 pthread_mutex_unlock(&ua_sess->lock);
4666
4667 end_not_compatible:
4668 rcu_read_unlock();
4669 health_code_update();
4670 return retval;
4671 }
4672
4673 /*
4674 * Flush buffers for all applications for a specific UST session.
4675 * Called with UST session lock held.
4676 */
4677 static
4678 int ust_app_flush_session(struct ltt_ust_session *usess)
4679
4680 {
4681 int ret = 0;
4682
4683 DBG("Flushing session buffers for all ust apps");
4684
4685 rcu_read_lock();
4686
4687 /* Flush buffers and push metadata. */
4688 switch (usess->buffer_type) {
4689 case LTTNG_BUFFER_PER_UID:
4690 {
4691 struct buffer_reg_uid *reg;
4692 struct lttng_ht_iter iter;
4693
4694 /* Flush all per UID buffers associated to that session. */
4695 cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
4696 struct ust_registry_session *ust_session_reg;
4697 struct buffer_reg_channel *reg_chan;
4698 struct consumer_socket *socket;
4699
4700 /* Get consumer socket to use to push the metadata.*/
4701 socket = consumer_find_socket_by_bitness(reg->bits_per_long,
4702 usess->consumer);
4703 if (!socket) {
4704 /* Ignore request if no consumer is found for the session. */
4705 continue;
4706 }
4707
4708 cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter,
4709 reg_chan, node.node) {
4710 /*
4711 * The following call will print error values so the return
4712 * code is of little importance because whatever happens, we
4713 * have to try them all.
4714 */
4715 (void) consumer_flush_channel(socket, reg_chan->consumer_key);
4716 }
4717
4718 ust_session_reg = reg->registry->reg.ust;
4719 /* Push metadata. */
4720 (void) push_metadata(ust_session_reg, usess->consumer);
4721 }
4722 break;
4723 }
4724 case LTTNG_BUFFER_PER_PID:
4725 {
4726 struct ust_app_session *ua_sess;
4727 struct lttng_ht_iter iter;
4728 struct ust_app *app;
4729
4730 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4731 ua_sess = lookup_session_by_app(usess, app);
4732 if (ua_sess == NULL) {
4733 continue;
4734 }
4735 (void) ust_app_flush_app_session(app, ua_sess);
4736 }
4737 break;
4738 }
4739 default:
4740 ret = -1;
4741 assert(0);
4742 break;
4743 }
4744
4745 rcu_read_unlock();
4746 health_code_update();
4747 return ret;
4748 }
4749
4750 static
4751 int ust_app_clear_quiescent_app_session(struct ust_app *app,
4752 struct ust_app_session *ua_sess)
4753 {
4754 int ret = 0;
4755 struct lttng_ht_iter iter;
4756 struct ust_app_channel *ua_chan;
4757 struct consumer_socket *socket;
4758
4759 DBG("Clearing stream quiescent state for ust app pid %d", app->pid);
4760
4761 rcu_read_lock();
4762
4763 if (!app->compatible) {
4764 goto end_not_compatible;
4765 }
4766
4767 pthread_mutex_lock(&ua_sess->lock);
4768
4769 if (ua_sess->deleted) {
4770 goto end_unlock;
4771 }
4772
4773 health_code_update();
4774
4775 socket = consumer_find_socket_by_bitness(app->bits_per_long,
4776 ua_sess->consumer);
4777 if (!socket) {
4778 ERR("Failed to find consumer (%" PRIu32 ") socket",
4779 app->bits_per_long);
4780 ret = -1;
4781 goto end_unlock;
4782 }
4783
4784 /* Clear quiescent state. */
4785 switch (ua_sess->buffer_type) {
4786 case LTTNG_BUFFER_PER_PID:
4787 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter,
4788 ua_chan, node.node) {
4789 health_code_update();
4790 ret = consumer_clear_quiescent_channel(socket,
4791 ua_chan->key);
4792 if (ret) {
4793 ERR("Error clearing quiescent state for consumer channel");
4794 ret = -1;
4795 continue;
4796 }
4797 }
4798 break;
4799 case LTTNG_BUFFER_PER_UID:
4800 default:
4801 assert(0);
4802 ret = -1;
4803 break;
4804 }
4805
4806 health_code_update();
4807
4808 end_unlock:
4809 pthread_mutex_unlock(&ua_sess->lock);
4810
4811 end_not_compatible:
4812 rcu_read_unlock();
4813 health_code_update();
4814 return ret;
4815 }
4816
4817 /*
4818 * Clear quiescent state in each stream for all applications for a
4819 * specific UST session.
4820 * Called with UST session lock held.
4821 */
4822 static
4823 int ust_app_clear_quiescent_session(struct ltt_ust_session *usess)
4824
4825 {
4826 int ret = 0;
4827
4828 DBG("Clearing stream quiescent state for all ust apps");
4829
4830 rcu_read_lock();
4831
4832 switch (usess->buffer_type) {
4833 case LTTNG_BUFFER_PER_UID:
4834 {
4835 struct lttng_ht_iter iter;
4836 struct buffer_reg_uid *reg;
4837
4838 /*
4839 * Clear quiescent for all per UID buffers associated to
4840 * that session.
4841 */
4842 cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
4843 struct consumer_socket *socket;
4844 struct buffer_reg_channel *reg_chan;
4845
4846 /* Get associated consumer socket.*/
4847 socket = consumer_find_socket_by_bitness(
4848 reg->bits_per_long, usess->consumer);
4849 if (!socket) {
4850 /*
4851 * Ignore request if no consumer is found for
4852 * the session.
4853 */
4854 continue;
4855 }
4856
4857 cds_lfht_for_each_entry(reg->registry->channels->ht,
4858 &iter.iter, reg_chan, node.node) {
4859 /*
4860 * The following call will print error values so
4861 * the return code is of little importance
4862 * because whatever happens, we have to try them
4863 * all.
4864 */
4865 (void) consumer_clear_quiescent_channel(socket,
4866 reg_chan->consumer_key);
4867 }
4868 }
4869 break;
4870 }
4871 case LTTNG_BUFFER_PER_PID:
4872 {
4873 struct ust_app_session *ua_sess;
4874 struct lttng_ht_iter iter;
4875 struct ust_app *app;
4876
4877 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app,
4878 pid_n.node) {
4879 ua_sess = lookup_session_by_app(usess, app);
4880 if (ua_sess == NULL) {
4881 continue;
4882 }
4883 (void) ust_app_clear_quiescent_app_session(app,
4884 ua_sess);
4885 }
4886 break;
4887 }
4888 default:
4889 ret = -1;
4890 assert(0);
4891 break;
4892 }
4893
4894 rcu_read_unlock();
4895 health_code_update();
4896 return ret;
4897 }
4898
4899 /*
4900 * Destroy a specific UST session in apps.
4901 */
4902 static int destroy_trace(struct ltt_ust_session *usess, struct ust_app *app)
4903 {
4904 int ret;
4905 struct ust_app_session *ua_sess;
4906 struct lttng_ht_iter iter;
4907 struct lttng_ht_node_u64 *node;
4908
4909 DBG("Destroy tracing for ust app pid %d", app->pid);
4910
4911 rcu_read_lock();
4912
4913 if (!app->compatible) {
4914 goto end;
4915 }
4916
4917 __lookup_session_by_app(usess, app, &iter);
4918 node = lttng_ht_iter_get_node_u64(&iter);
4919 if (node == NULL) {
4920 /* Session is being or is deleted. */
4921 goto end;
4922 }
4923 ua_sess = caa_container_of(node, struct ust_app_session, node);
4924
4925 health_code_update();
4926 destroy_app_session(app, ua_sess);
4927
4928 health_code_update();
4929
4930 /* Quiescent wait after stopping trace */
4931 pthread_mutex_lock(&app->sock_lock);
4932 ret = ustctl_wait_quiescent(app->sock);
4933 pthread_mutex_unlock(&app->sock_lock);
4934 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
4935 ERR("UST app wait quiescent failed for app pid %d ret %d",
4936 app->pid, ret);
4937 }
4938 end:
4939 rcu_read_unlock();
4940 health_code_update();
4941 return 0;
4942 }
4943
4944 /*
4945 * Start tracing for the UST session.
4946 */
4947 int ust_app_start_trace_all(struct ltt_ust_session *usess)
4948 {
4949 int ret = 0;
4950 struct lttng_ht_iter iter;
4951 struct ust_app *app;
4952
4953 DBG("Starting all UST traces");
4954
4955 rcu_read_lock();
4956
4957 /*
4958 * In a start-stop-start use-case, we need to clear the quiescent state
4959 * of each channel set by the prior stop command, thus ensuring that a
4960 * following stop or destroy is sure to grab a timestamp_end near those
4961 * operations, even if the packet is empty.
4962 */
4963 (void) ust_app_clear_quiescent_session(usess);
4964
4965 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4966 ret = ust_app_start_trace(usess, app);
4967 if (ret < 0) {
4968 /* Continue to next apps even on error */
4969 continue;
4970 }
4971 }
4972
4973 rcu_read_unlock();
4974
4975 return 0;
4976 }
4977
4978 /*
4979 * Start tracing for the UST session.
4980 * Called with UST session lock held.
4981 */
4982 int ust_app_stop_trace_all(struct ltt_ust_session *usess)
4983 {
4984 int ret = 0;
4985 struct lttng_ht_iter iter;
4986 struct ust_app *app;
4987
4988 DBG("Stopping all UST traces");
4989
4990 rcu_read_lock();
4991
4992 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4993 ret = ust_app_stop_trace(usess, app);
4994 if (ret < 0) {
4995 /* Continue to next apps even on error */
4996 continue;
4997 }
4998 }
4999
5000 (void) ust_app_flush_session(usess);
5001
5002 rcu_read_unlock();
5003
5004 return 0;
5005 }
5006
5007 /*
5008 * Destroy app UST session.
5009 */
5010 int ust_app_destroy_trace_all(struct ltt_ust_session *usess)
5011 {
5012 int ret = 0;
5013 struct lttng_ht_iter iter;
5014 struct ust_app *app;
5015
5016 DBG("Destroy all UST traces");
5017
5018 rcu_read_lock();
5019
5020 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
5021 ret = destroy_trace(usess, app);
5022 if (ret < 0) {
5023 /* Continue to next apps even on error */
5024 continue;
5025 }
5026 }
5027
5028 rcu_read_unlock();
5029
5030 return 0;
5031 }
5032
5033 static
5034 void ust_app_global_create(struct ltt_ust_session *usess, struct ust_app *app)
5035 {
5036 int ret = 0;
5037 struct lttng_ht_iter iter, uiter;
5038 struct ust_app_session *ua_sess = NULL;
5039 struct ust_app_channel *ua_chan;
5040 struct ust_app_event *ua_event;
5041 struct ust_app_ctx *ua_ctx;
5042 int is_created = 0;
5043
5044 ret = find_or_create_ust_app_session(usess, app, &ua_sess, &is_created);
5045 if (ret < 0) {
5046 /* Tracer is probably gone or ENOMEM. */
5047 goto error;
5048 }
5049 if (!is_created) {
5050 /* App session already created. */
5051 goto end;
5052 }
5053 assert(ua_sess);
5054
5055 pthread_mutex_lock(&ua_sess->lock);
5056
5057 if (ua_sess->deleted) {
5058 pthread_mutex_unlock(&ua_sess->lock);
5059 goto end;
5060 }
5061
5062 /*
5063 * We can iterate safely here over all UST app session since the create ust
5064 * app session above made a shadow copy of the UST global domain from the
5065 * ltt ust session.
5066 */
5067 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
5068 node.node) {
5069 ret = do_create_channel(app, usess, ua_sess, ua_chan);
5070 if (ret < 0 && ret != -ENOTCONN) {
5071 /*
5072 * Stop everything. On error, the application
5073 * failed, no more file descriptor are available
5074 * or ENOMEM so stopping here is the only thing
5075 * we can do for now. The only exception is
5076 * -ENOTCONN, which indicates that the application
5077 * has exit.
5078 */
5079 goto error_unlock;
5080 }
5081
5082 /*
5083 * Add context using the list so they are enabled in the same order the
5084 * user added them.
5085 */
5086 cds_list_for_each_entry(ua_ctx, &ua_chan->ctx_list, list) {
5087 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
5088 if (ret < 0) {
5089 goto error_unlock;
5090 }
5091 }
5092
5093
5094 /* For each events */
5095 cds_lfht_for_each_entry(ua_chan->events->ht, &uiter.iter, ua_event,
5096 node.node) {
5097 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
5098 if (ret < 0) {
5099 goto error_unlock;
5100 }
5101 }
5102 }
5103
5104 pthread_mutex_unlock(&ua_sess->lock);
5105
5106 if (usess->active) {
5107 ret = ust_app_start_trace(usess, app);
5108 if (ret < 0) {
5109 goto error;
5110 }
5111
5112 DBG2("UST trace started for app pid %d", app->pid);
5113 }
5114 end:
5115 /* Everything went well at this point. */
5116 return;
5117
5118 error_unlock:
5119 pthread_mutex_unlock(&ua_sess->lock);
5120 error:
5121 if (ua_sess) {
5122 destroy_app_session(app, ua_sess);
5123 }
5124 return;
5125 }
5126
5127 static
5128 void ust_app_global_destroy(struct ltt_ust_session *usess, struct ust_app *app)
5129 {
5130 struct ust_app_session *ua_sess;
5131
5132 ua_sess = lookup_session_by_app(usess, app);
5133 if (ua_sess == NULL) {
5134 return;
5135 }
5136 destroy_app_session(app, ua_sess);
5137 }
5138
5139 /*
5140 * Add channels/events from UST global domain to registered apps at sock.
5141 *
5142 * Called with session lock held.
5143 * Called with RCU read-side lock held.
5144 */
5145 void ust_app_global_update(struct ltt_ust_session *usess, struct ust_app *app)
5146 {
5147 assert(usess);
5148
5149 DBG2("UST app global update for app sock %d for session id %" PRIu64,
5150 app->sock, usess->id);
5151
5152 if (!app->compatible) {
5153 return;
5154 }
5155
5156 if (trace_ust_pid_tracker_lookup(usess, app->pid)) {
5157 ust_app_global_create(usess, app);
5158 } else {
5159 ust_app_global_destroy(usess, app);
5160 }
5161 }
5162
5163 /*
5164 * Called with session lock held.
5165 */
5166 void ust_app_global_update_all(struct ltt_ust_session *usess)
5167 {
5168 struct lttng_ht_iter iter;
5169 struct ust_app *app;
5170
5171 rcu_read_lock();
5172 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
5173 ust_app_global_update(usess, app);
5174 }
5175 rcu_read_unlock();
5176 }
5177
5178 /*
5179 * Add context to a specific channel for global UST domain.
5180 */
5181 int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess,
5182 struct ltt_ust_channel *uchan, struct ltt_ust_context *uctx)
5183 {
5184 int ret = 0;
5185 struct lttng_ht_node_str *ua_chan_node;
5186 struct lttng_ht_iter iter, uiter;
5187 struct ust_app_channel *ua_chan = NULL;
5188 struct ust_app_session *ua_sess;
5189 struct ust_app *app;
5190
5191 rcu_read_lock();
5192
5193 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
5194 if (!app->compatible) {
5195 /*
5196 * TODO: In time, we should notice the caller of this error by
5197 * telling him that this is a version error.
5198 */
5199 continue;
5200 }
5201 ua_sess = lookup_session_by_app(usess, app);
5202 if (ua_sess == NULL) {
5203 continue;
5204 }
5205
5206 pthread_mutex_lock(&ua_sess->lock);
5207
5208 if (ua_sess->deleted) {
5209 pthread_mutex_unlock(&ua_sess->lock);
5210 continue;
5211 }
5212
5213 /* Lookup channel in the ust app session */
5214 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
5215 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
5216 if (ua_chan_node == NULL) {
5217 goto next_app;
5218 }
5219 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel,
5220 node);
5221 ret = create_ust_app_channel_context(ua_sess, ua_chan, &uctx->ctx, app);
5222 if (ret < 0) {
5223 goto next_app;
5224 }
5225 next_app:
5226 pthread_mutex_unlock(&ua_sess->lock);
5227 }
5228
5229 rcu_read_unlock();
5230 return ret;
5231 }
5232
5233 /*
5234 * Enable event for a channel from a UST session for a specific PID.
5235 */
5236 int ust_app_enable_event_pid(struct ltt_ust_session *usess,
5237 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent, pid_t pid)
5238 {
5239 int ret = 0;
5240 struct lttng_ht_iter iter;
5241 struct lttng_ht_node_str *ua_chan_node;
5242 struct ust_app *app;
5243 struct ust_app_session *ua_sess;
5244 struct ust_app_channel *ua_chan;
5245 struct ust_app_event *ua_event;
5246
5247 DBG("UST app enabling event %s for PID %d", uevent->attr.name, pid);
5248
5249 rcu_read_lock();
5250
5251 app = ust_app_find_by_pid(pid);
5252 if (app == NULL) {
5253 ERR("UST app enable event per PID %d not found", pid);
5254 ret = -1;
5255 goto end;
5256 }
5257
5258 if (!app->compatible) {
5259 ret = 0;
5260 goto end;
5261 }
5262
5263 ua_sess = lookup_session_by_app(usess, app);
5264 if (!ua_sess) {
5265 /* The application has problem or is probably dead. */
5266 ret = 0;
5267 goto end;
5268 }
5269
5270 pthread_mutex_lock(&ua_sess->lock);
5271
5272 if (ua_sess->deleted) {
5273 ret = 0;
5274 goto end_unlock;
5275 }
5276
5277 /* Lookup channel in the ust app session */
5278 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
5279 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
5280 /* If the channel is not found, there is a code flow error */
5281 assert(ua_chan_node);
5282
5283 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
5284
5285 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
5286 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
5287 if (ua_event == NULL) {
5288 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
5289 if (ret < 0) {
5290 goto end_unlock;
5291 }
5292 } else {
5293 ret = enable_ust_app_event(ua_sess, ua_event, app);
5294 if (ret < 0) {
5295 goto end_unlock;
5296 }
5297 }
5298
5299 end_unlock:
5300 pthread_mutex_unlock(&ua_sess->lock);
5301 end:
5302 rcu_read_unlock();
5303 return ret;
5304 }
5305
5306 /*
5307 * Receive registration and populate the given msg structure.
5308 *
5309 * On success return 0 else a negative value returned by the ustctl call.
5310 */
5311 int ust_app_recv_registration(int sock, struct ust_register_msg *msg)
5312 {
5313 int ret;
5314 uint32_t pid, ppid, uid, gid;
5315
5316 assert(msg);
5317
5318 ret = ustctl_recv_reg_msg(sock, &msg->type, &msg->major, &msg->minor,
5319 &pid, &ppid, &uid, &gid,
5320 &msg->bits_per_long,
5321 &msg->uint8_t_alignment,
5322 &msg->uint16_t_alignment,
5323 &msg->uint32_t_alignment,
5324 &msg->uint64_t_alignment,
5325 &msg->long_alignment,
5326 &msg->byte_order,
5327 msg->name);
5328 if (ret < 0) {
5329 switch (-ret) {
5330 case EPIPE:
5331 case ECONNRESET:
5332 case LTTNG_UST_ERR_EXITING:
5333 DBG3("UST app recv reg message failed. Application died");
5334 break;
5335 case LTTNG_UST_ERR_UNSUP_MAJOR:
5336 ERR("UST app recv reg unsupported version %d.%d. Supporting %d.%d",
5337 msg->major, msg->minor, LTTNG_UST_ABI_MAJOR_VERSION,
5338 LTTNG_UST_ABI_MINOR_VERSION);
5339 break;
5340 default:
5341 ERR("UST app recv reg message failed with ret %d", ret);
5342 break;
5343 }
5344 goto error;
5345 }
5346 msg->pid = (pid_t) pid;
5347 msg->ppid = (pid_t) ppid;
5348 msg->uid = (uid_t) uid;
5349 msg->gid = (gid_t) gid;
5350
5351 error:
5352 return ret;
5353 }
5354
5355 /*
5356 * Return a ust app session object using the application object and the
5357 * session object descriptor has a key. If not found, NULL is returned.
5358 * A RCU read side lock MUST be acquired when calling this function.
5359 */
5360 static struct ust_app_session *find_session_by_objd(struct ust_app *app,
5361 int objd)
5362 {
5363 struct lttng_ht_node_ulong *node;
5364 struct lttng_ht_iter iter;
5365 struct ust_app_session *ua_sess = NULL;
5366
5367 assert(app);
5368
5369 lttng_ht_lookup(app->ust_sessions_objd, (void *)((unsigned long) objd), &iter);
5370 node = lttng_ht_iter_get_node_ulong(&iter);
5371 if (node == NULL) {
5372 DBG2("UST app session find by objd %d not found", objd);
5373 goto error;
5374 }
5375
5376 ua_sess = caa_container_of(node, struct ust_app_session, ust_objd_node);
5377
5378 error:
5379 return ua_sess;
5380 }
5381
5382 /*
5383 * Return a ust app channel object using the application object and the channel
5384 * object descriptor has a key. If not found, NULL is returned. A RCU read side
5385 * lock MUST be acquired before calling this function.
5386 */
5387 static struct ust_app_channel *find_channel_by_objd(struct ust_app *app,
5388 int objd)
5389 {
5390 struct lttng_ht_node_ulong *node;
5391 struct lttng_ht_iter iter;
5392 struct ust_app_channel *ua_chan = NULL;
5393
5394 assert(app);
5395
5396 lttng_ht_lookup(app->ust_objd, (void *)((unsigned long) objd), &iter);
5397 node = lttng_ht_iter_get_node_ulong(&iter);
5398 if (node == NULL) {
5399 DBG2("UST app channel find by objd %d not found", objd);
5400 goto error;
5401 }
5402
5403 ua_chan = caa_container_of(node, struct ust_app_channel, ust_objd_node);
5404
5405 error:
5406 return ua_chan;
5407 }
5408
5409 /*
5410 * Reply to a register channel notification from an application on the notify
5411 * socket. The channel metadata is also created.
5412 *
5413 * The session UST registry lock is acquired in this function.
5414 *
5415 * On success 0 is returned else a negative value.
5416 */
5417 static int reply_ust_register_channel(int sock, int sobjd, int cobjd,
5418 size_t nr_fields, struct ustctl_field *fields)
5419 {
5420 int ret, ret_code = 0;
5421 uint32_t chan_id, reg_count;
5422 uint64_t chan_reg_key;
5423 enum ustctl_channel_header type;
5424 struct ust_app *app;
5425 struct ust_app_channel *ua_chan;
5426 struct ust_app_session *ua_sess;
5427 struct ust_registry_session *registry;
5428 struct ust_registry_channel *chan_reg;
5429
5430 rcu_read_lock();
5431
5432 /* Lookup application. If not found, there is a code flow error. */
5433 app = find_app_by_notify_sock(sock);
5434 if (!app) {
5435 DBG("Application socket %d is being torn down. Abort event notify",
5436 sock);
5437 ret = 0;
5438 goto error_rcu_unlock;
5439 }
5440
5441 /* Lookup channel by UST object descriptor. */
5442 ua_chan = find_channel_by_objd(app, cobjd);
5443 if (!ua_chan) {
5444 DBG("Application channel is being torn down. Abort event notify");
5445 ret = 0;
5446 goto error_rcu_unlock;
5447 }
5448
5449 assert(ua_chan->session);
5450 ua_sess = ua_chan->session;
5451
5452 /* Get right session registry depending on the session buffer type. */
5453 registry = get_session_registry(ua_sess);
5454 if (!registry) {
5455 DBG("Application session is being torn down. Abort event notify");
5456 ret = 0;
5457 goto error_rcu_unlock;
5458 };
5459
5460 /* Depending on the buffer type, a different channel key is used. */
5461 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) {
5462 chan_reg_key = ua_chan->tracing_channel_id;
5463 } else {
5464 chan_reg_key = ua_chan->key;
5465 }
5466
5467 pthread_mutex_lock(&registry->lock);
5468
5469 chan_reg = ust_registry_channel_find(registry, chan_reg_key);
5470 assert(chan_reg);
5471
5472 if (!chan_reg->register_done) {
5473 reg_count = ust_registry_get_event_count(chan_reg);
5474 if (reg_count < 31) {
5475 type = USTCTL_CHANNEL_HEADER_COMPACT;
5476 } else {
5477 type = USTCTL_CHANNEL_HEADER_LARGE;
5478 }
5479
5480 chan_reg->nr_ctx_fields = nr_fields;
5481 chan_reg->ctx_fields = fields;
5482 fields = NULL;
5483 chan_reg->header_type = type;
5484 } else {
5485 /* Get current already assigned values. */
5486 type = chan_reg->header_type;
5487 }
5488 /* Channel id is set during the object creation. */
5489 chan_id = chan_reg->chan_id;
5490
5491 /* Append to metadata */
5492 if (!chan_reg->metadata_dumped) {
5493 ret_code = ust_metadata_channel_statedump(registry, chan_reg);
5494 if (ret_code) {
5495 ERR("Error appending channel metadata (errno = %d)", ret_code);
5496 goto reply;
5497 }
5498 }
5499
5500 reply:
5501 DBG3("UST app replying to register channel key %" PRIu64
5502 " with id %u, type: %d, ret: %d", chan_reg_key, chan_id, type,
5503 ret_code);
5504
5505 ret = ustctl_reply_register_channel(sock, chan_id, type, ret_code);
5506 if (ret < 0) {
5507 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5508 ERR("UST app reply channel failed with ret %d", ret);
5509 } else {
5510 DBG3("UST app reply channel failed. Application died");
5511 }
5512 goto error;
5513 }
5514
5515 /* This channel registry registration is completed. */
5516 chan_reg->register_done = 1;
5517
5518 error:
5519 pthread_mutex_unlock(&registry->lock);
5520 error_rcu_unlock:
5521 rcu_read_unlock();
5522 free(fields);
5523 return ret;
5524 }
5525
5526 /*
5527 * Add event to the UST channel registry. When the event is added to the
5528 * registry, the metadata is also created. Once done, this replies to the
5529 * application with the appropriate error code.
5530 *
5531 * The session UST registry lock is acquired in the function.
5532 *
5533 * On success 0 is returned else a negative value.
5534 */
5535 static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name,
5536 char *sig, size_t nr_fields, struct ustctl_field *fields,
5537 int loglevel_value, char *model_emf_uri)
5538 {
5539 int ret, ret_code;
5540 uint32_t event_id = 0;
5541 uint64_t chan_reg_key;
5542 struct ust_app *app;
5543 struct ust_app_channel *ua_chan;
5544 struct ust_app_session *ua_sess;
5545 struct ust_registry_session *registry;
5546
5547 rcu_read_lock();
5548
5549 /* Lookup application. If not found, there is a code flow error. */
5550 app = find_app_by_notify_sock(sock);
5551 if (!app) {
5552 DBG("Application socket %d is being torn down. Abort event notify",
5553 sock);
5554 ret = 0;
5555 goto error_rcu_unlock;
5556 }
5557
5558 /* Lookup channel by UST object descriptor. */
5559 ua_chan = find_channel_by_objd(app, cobjd);
5560 if (!ua_chan) {
5561 DBG("Application channel is being torn down. Abort event notify");
5562 ret = 0;
5563 goto error_rcu_unlock;
5564 }
5565
5566 assert(ua_chan->session);
5567 ua_sess = ua_chan->session;
5568
5569 registry = get_session_registry(ua_sess);
5570 if (!registry) {
5571 DBG("Application session is being torn down. Abort event notify");
5572 ret = 0;
5573 goto error_rcu_unlock;
5574 }
5575
5576 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) {
5577 chan_reg_key = ua_chan->tracing_channel_id;
5578 } else {
5579 chan_reg_key = ua_chan->key;
5580 }
5581
5582 pthread_mutex_lock(&registry->lock);
5583
5584 /*
5585 * From this point on, this call acquires the ownership of the sig, fields
5586 * and model_emf_uri meaning any free are done inside it if needed. These
5587 * three variables MUST NOT be read/write after this.
5588 */
5589 ret_code = ust_registry_create_event(registry, chan_reg_key,
5590 sobjd, cobjd, name, sig, nr_fields, fields,
5591 loglevel_value, model_emf_uri, ua_sess->buffer_type,
5592 &event_id, app);
5593 sig = NULL;
5594 fields = NULL;
5595 model_emf_uri = NULL;
5596
5597 /*
5598 * The return value is returned to ustctl so in case of an error, the
5599 * application can be notified. In case of an error, it's important not to
5600 * return a negative error or else the application will get closed.
5601 */
5602 ret = ustctl_reply_register_event(sock, event_id, ret_code);
5603 if (ret < 0) {
5604 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5605 ERR("UST app reply event failed with ret %d", ret);
5606 } else {
5607 DBG3("UST app reply event failed. Application died");
5608 }
5609 /*
5610 * No need to wipe the create event since the application socket will
5611 * get close on error hence cleaning up everything by itself.
5612 */
5613 goto error;
5614 }
5615
5616 DBG3("UST registry event %s with id %" PRId32 " added successfully",
5617 name, event_id);
5618
5619 error:
5620 pthread_mutex_unlock(&registry->lock);
5621 error_rcu_unlock:
5622 rcu_read_unlock();
5623 free(sig);
5624 free(fields);
5625 free(model_emf_uri);
5626 return ret;
5627 }
5628
5629 /*
5630 * Add enum to the UST session registry. Once done, this replies to the
5631 * application with the appropriate error code.
5632 *
5633 * The session UST registry lock is acquired within this function.
5634 *
5635 * On success 0 is returned else a negative value.
5636 */
5637 static int add_enum_ust_registry(int sock, int sobjd, char *name,
5638 struct ustctl_enum_entry *entries, size_t nr_entries)
5639 {
5640 int ret = 0, ret_code;
5641 struct ust_app *app;
5642 struct ust_app_session *ua_sess;
5643 struct ust_registry_session *registry;
5644 uint64_t enum_id = -1ULL;
5645
5646 rcu_read_lock();
5647
5648 /* Lookup application. If not found, there is a code flow error. */
5649 app = find_app_by_notify_sock(sock);
5650 if (!app) {
5651 /* Return an error since this is not an error */
5652 DBG("Application socket %d is being torn down. Aborting enum registration",
5653 sock);
5654 free(entries);
5655 goto error_rcu_unlock;
5656 }
5657
5658 /* Lookup session by UST object descriptor. */
5659 ua_sess = find_session_by_objd(app, sobjd);
5660 if (!ua_sess) {
5661 /* Return an error since this is not an error */
5662 DBG("Application session is being torn down (session not found). Aborting enum registration.");
5663 free(entries);
5664 goto error_rcu_unlock;
5665 }
5666
5667 registry = get_session_registry(ua_sess);
5668 if (!registry) {
5669 DBG("Application session is being torn down (registry not found). Aborting enum registration.");
5670 free(entries);
5671 goto error_rcu_unlock;
5672 }
5673
5674 pthread_mutex_lock(&registry->lock);
5675
5676 /*
5677 * From this point on, the callee acquires the ownership of
5678 * entries. The variable entries MUST NOT be read/written after
5679 * call.
5680 */
5681 ret_code = ust_registry_create_or_find_enum(registry, sobjd, name,
5682 entries, nr_entries, &enum_id);
5683 entries = NULL;
5684
5685 /*
5686 * The return value is returned to ustctl so in case of an error, the
5687 * application can be notified. In case of an error, it's important not to
5688 * return a negative error or else the application will get closed.
5689 */
5690 ret = ustctl_reply_register_enum(sock, enum_id, ret_code);
5691 if (ret < 0) {
5692 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5693 ERR("UST app reply enum failed with ret %d", ret);
5694 } else {
5695 DBG3("UST app reply enum failed. Application died");
5696 }
5697 /*
5698 * No need to wipe the create enum since the application socket will
5699 * get close on error hence cleaning up everything by itself.
5700 */
5701 goto error;
5702 }
5703
5704 DBG3("UST registry enum %s added successfully or already found", name);
5705
5706 error:
5707 pthread_mutex_unlock(&registry->lock);
5708 error_rcu_unlock:
5709 rcu_read_unlock();
5710 return ret;
5711 }
5712
5713 /*
5714 * Handle application notification through the given notify socket.
5715 *
5716 * Return 0 on success or else a negative value.
5717 */
5718 int ust_app_recv_notify(int sock)
5719 {
5720 int ret;
5721 enum ustctl_notify_cmd cmd;
5722
5723 DBG3("UST app receiving notify from sock %d", sock);
5724
5725 ret = ustctl_recv_notify(sock, &cmd);
5726 if (ret < 0) {
5727 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5728 ERR("UST app recv notify failed with ret %d", ret);
5729 } else {
5730 DBG3("UST app recv notify failed. Application died");
5731 }
5732 goto error;
5733 }
5734
5735 switch (cmd) {
5736 case USTCTL_NOTIFY_CMD_EVENT:
5737 {
5738 int sobjd, cobjd, loglevel_value;
5739 char name[LTTNG_UST_SYM_NAME_LEN], *sig, *model_emf_uri;
5740 size_t nr_fields;
5741 struct ustctl_field *fields;
5742
5743 DBG2("UST app ustctl register event received");
5744
5745 ret = ustctl_recv_register_event(sock, &sobjd, &cobjd, name,
5746 &loglevel_value, &sig, &nr_fields, &fields,
5747 &model_emf_uri);
5748 if (ret < 0) {
5749 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5750 ERR("UST app recv event failed with ret %d", ret);
5751 } else {
5752 DBG3("UST app recv event failed. Application died");
5753 }
5754 goto error;
5755 }
5756
5757 /*
5758 * Add event to the UST registry coming from the notify socket. This
5759 * call will free if needed the sig, fields and model_emf_uri. This
5760 * code path loses the ownsership of these variables and transfer them
5761 * to the this function.
5762 */
5763 ret = add_event_ust_registry(sock, sobjd, cobjd, name, sig, nr_fields,
5764 fields, loglevel_value, model_emf_uri);
5765 if (ret < 0) {
5766 goto error;
5767 }
5768
5769 break;
5770 }
5771 case USTCTL_NOTIFY_CMD_CHANNEL:
5772 {
5773 int sobjd, cobjd;
5774 size_t nr_fields;
5775 struct ustctl_field *fields;
5776
5777 DBG2("UST app ustctl register channel received");
5778
5779 ret = ustctl_recv_register_channel(sock, &sobjd, &cobjd, &nr_fields,
5780 &fields);
5781 if (ret < 0) {
5782 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5783 ERR("UST app recv channel failed with ret %d", ret);
5784 } else {
5785 DBG3("UST app recv channel failed. Application died");
5786 }
5787 goto error;
5788 }
5789
5790 /*
5791 * The fields ownership are transfered to this function call meaning
5792 * that if needed it will be freed. After this, it's invalid to access
5793 * fields or clean it up.
5794 */
5795 ret = reply_ust_register_channel(sock, sobjd, cobjd, nr_fields,
5796 fields);
5797 if (ret < 0) {
5798 goto error;
5799 }
5800
5801 break;
5802 }
5803 case USTCTL_NOTIFY_CMD_ENUM:
5804 {
5805 int sobjd;
5806 char name[LTTNG_UST_SYM_NAME_LEN];
5807 size_t nr_entries;
5808 struct ustctl_enum_entry *entries;
5809
5810 DBG2("UST app ustctl register enum received");
5811
5812 ret = ustctl_recv_register_enum(sock, &sobjd, name,
5813 &entries, &nr_entries);
5814 if (ret < 0) {
5815 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5816 ERR("UST app recv enum failed with ret %d", ret);
5817 } else {
5818 DBG3("UST app recv enum failed. Application died");
5819 }
5820 goto error;
5821 }
5822
5823 /* Callee assumes ownership of entries */
5824 ret = add_enum_ust_registry(sock, sobjd, name,
5825 entries, nr_entries);
5826 if (ret < 0) {
5827 goto error;
5828 }
5829
5830 break;
5831 }
5832 default:
5833 /* Should NEVER happen. */
5834 assert(0);
5835 }
5836
5837 error:
5838 return ret;
5839 }
5840
5841 /*
5842 * Once the notify socket hangs up, this is called. First, it tries to find the
5843 * corresponding application. On failure, the call_rcu to close the socket is
5844 * executed. If an application is found, it tries to delete it from the notify
5845 * socket hash table. Whathever the result, it proceeds to the call_rcu.
5846 *
5847 * Note that an object needs to be allocated here so on ENOMEM failure, the
5848 * call RCU is not done but the rest of the cleanup is.
5849 */
5850 void ust_app_notify_sock_unregister(int sock)
5851 {
5852 int err_enomem = 0;
5853 struct lttng_ht_iter iter;
5854 struct ust_app *app;
5855 struct ust_app_notify_sock_obj *obj;
5856
5857 assert(sock >= 0);
5858
5859 rcu_read_lock();
5860
5861 obj = zmalloc(sizeof(*obj));
5862 if (!obj) {
5863 /*
5864 * An ENOMEM is kind of uncool. If this strikes we continue the
5865 * procedure but the call_rcu will not be called. In this case, we
5866 * accept the fd leak rather than possibly creating an unsynchronized
5867 * state between threads.
5868 *
5869 * TODO: The notify object should be created once the notify socket is
5870 * registered and stored independantely from the ust app object. The
5871 * tricky part is to synchronize the teardown of the application and
5872 * this notify object. Let's keep that in mind so we can avoid this
5873 * kind of shenanigans with ENOMEM in the teardown path.
5874 */
5875 err_enomem = 1;
5876 } else {
5877 obj->fd = sock;
5878 }
5879
5880 DBG("UST app notify socket unregister %d", sock);
5881
5882 /*
5883 * Lookup application by notify socket. If this fails, this means that the
5884 * hash table delete has already been done by the application
5885 * unregistration process so we can safely close the notify socket in a
5886 * call RCU.
5887 */
5888 app = find_app_by_notify_sock(sock);
5889 if (!app) {
5890 goto close_socket;
5891 }
5892
5893 iter.iter.node = &app->notify_sock_n.node;
5894
5895 /*
5896 * Whatever happens here either we fail or succeed, in both cases we have
5897 * to close the socket after a grace period to continue to the call RCU
5898 * here. If the deletion is successful, the application is not visible
5899 * anymore by other threads and is it fails it means that it was already
5900 * deleted from the hash table so either way we just have to close the
5901 * socket.
5902 */
5903 (void) lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
5904
5905 close_socket:
5906 rcu_read_unlock();
5907
5908 /*
5909 * Close socket after a grace period to avoid for the socket to be reused
5910 * before the application object is freed creating potential race between
5911 * threads trying to add unique in the global hash table.
5912 */
5913 if (!err_enomem) {
5914 call_rcu(&obj->head, close_notify_sock_rcu);
5915 }
5916 }
5917
5918 /*
5919 * Destroy a ust app data structure and free its memory.
5920 */
5921 void ust_app_destroy(struct ust_app *app)
5922 {
5923 if (!app) {
5924 return;
5925 }
5926
5927 call_rcu(&app->pid_n.head, delete_ust_app_rcu);
5928 }
5929
5930 /*
5931 * Take a snapshot for a given UST session. The snapshot is sent to the given
5932 * output.
5933 *
5934 * Return 0 on success or else a negative value.
5935 */
5936 int ust_app_snapshot_record(struct ltt_ust_session *usess,
5937 struct snapshot_output *output, int wait,
5938 uint64_t nb_packets_per_stream)
5939 {
5940 int ret = 0;
5941 struct lttng_ht_iter iter;
5942 struct ust_app *app;
5943 char pathname[PATH_MAX];
5944
5945 assert(usess);
5946 assert(output);
5947
5948 rcu_read_lock();
5949
5950 switch (usess->buffer_type) {
5951 case LTTNG_BUFFER_PER_UID:
5952 {
5953 struct buffer_reg_uid *reg;
5954
5955 cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
5956 struct buffer_reg_channel *reg_chan;
5957 struct consumer_socket *socket;
5958
5959 /* Get consumer socket to use to push the metadata.*/
5960 socket = consumer_find_socket_by_bitness(reg->bits_per_long,
5961 usess->consumer);
5962 if (!socket) {
5963 ret = -EINVAL;
5964 goto error;
5965 }
5966
5967 memset(pathname, 0, sizeof(pathname));
5968 ret = snprintf(pathname, sizeof(pathname),
5969 DEFAULT_UST_TRACE_DIR "/" DEFAULT_UST_TRACE_UID_PATH,
5970 reg->uid, reg->bits_per_long);
5971 if (ret < 0) {
5972 PERROR("snprintf snapshot path");
5973 goto error;
5974 }
5975
5976 /* Add the UST default trace dir to path. */
5977 cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter,
5978 reg_chan, node.node) {
5979 ret = consumer_snapshot_channel(socket, reg_chan->consumer_key,
5980 output, 0, usess->uid, usess->gid, pathname, wait,
5981 nb_packets_per_stream);
5982 if (ret < 0) {
5983 goto error;
5984 }
5985 }
5986 ret = consumer_snapshot_channel(socket,
5987 reg->registry->reg.ust->metadata_key, output, 1,
5988 usess->uid, usess->gid, pathname, wait, 0);
5989 if (ret < 0) {
5990 goto error;
5991 }
5992 }
5993 break;
5994 }
5995 case LTTNG_BUFFER_PER_PID:
5996 {
5997 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
5998 struct consumer_socket *socket;
5999 struct lttng_ht_iter chan_iter;
6000 struct ust_app_channel *ua_chan;
6001 struct ust_app_session *ua_sess;
6002 struct ust_registry_session *registry;
6003
6004 ua_sess = lookup_session_by_app(usess, app);
6005 if (!ua_sess) {
6006 /* Session not associated with this app. */
6007 continue;
6008 }
6009
6010 /* Get the right consumer socket for the application. */
6011 socket = consumer_find_socket_by_bitness(app->bits_per_long,
6012 output->consumer);
6013 if (!socket) {
6014 ret = -EINVAL;
6015 goto error;
6016 }
6017
6018 /* Add the UST default trace dir to path. */
6019 memset(pathname, 0, sizeof(pathname));
6020 ret = snprintf(pathname, sizeof(pathname), DEFAULT_UST_TRACE_DIR "/%s",
6021 ua_sess->path);
6022 if (ret < 0) {
6023 PERROR("snprintf snapshot path");
6024 goto error;
6025 }
6026
6027 cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter,
6028 ua_chan, node.node) {
6029 ret = consumer_snapshot_channel(socket, ua_chan->key, output,
6030 0, ua_sess->euid, ua_sess->egid, pathname, wait,
6031 nb_packets_per_stream);
6032 if (ret < 0) {
6033 goto error;
6034 }
6035 }
6036
6037 registry = get_session_registry(ua_sess);
6038 if (!registry) {
6039 DBG("Application session is being torn down. Abort snapshot record.");
6040 ret = -1;
6041 goto error;
6042 }
6043 ret = consumer_snapshot_channel(socket, registry->metadata_key, output,
6044 1, ua_sess->euid, ua_sess->egid, pathname, wait, 0);
6045 if (ret < 0) {
6046 goto error;
6047 }
6048 }
6049 break;
6050 }
6051 default:
6052 assert(0);
6053 break;
6054 }
6055
6056 error:
6057 rcu_read_unlock();
6058 return ret;
6059 }
6060
6061 /*
6062 * Return the size taken by one more packet per stream.
6063 */
6064 uint64_t ust_app_get_size_one_more_packet_per_stream(struct ltt_ust_session *usess,
6065 uint64_t cur_nr_packets)
6066 {
6067 uint64_t tot_size = 0;
6068 struct ust_app *app;
6069 struct lttng_ht_iter iter;
6070
6071 assert(usess);
6072
6073 switch (usess->buffer_type) {
6074 case LTTNG_BUFFER_PER_UID:
6075 {
6076 struct buffer_reg_uid *reg;
6077
6078 cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
6079 struct buffer_reg_channel *reg_chan;
6080
6081 rcu_read_lock();
6082 cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter,
6083 reg_chan, node.node) {
6084 if (cur_nr_packets >= reg_chan->num_subbuf) {
6085 /*
6086 * Don't take channel into account if we
6087 * already grab all its packets.
6088 */
6089 continue;
6090 }
6091 tot_size += reg_chan->subbuf_size * reg_chan->stream_count;
6092 }
6093 rcu_read_unlock();
6094 }
6095 break;
6096 }
6097 case LTTNG_BUFFER_PER_PID:
6098 {
6099 rcu_read_lock();
6100 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
6101 struct ust_app_channel *ua_chan;
6102 struct ust_app_session *ua_sess;
6103 struct lttng_ht_iter chan_iter;
6104
6105 ua_sess = lookup_session_by_app(usess, app);
6106 if (!ua_sess) {
6107 /* Session not associated with this app. */
6108 continue;
6109 }
6110
6111 cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter,
6112 ua_chan, node.node) {
6113 if (cur_nr_packets >= ua_chan->attr.num_subbuf) {
6114 /*
6115 * Don't take channel into account if we
6116 * already grab all its packets.
6117 */
6118 continue;
6119 }
6120 tot_size += ua_chan->attr.subbuf_size * ua_chan->streams.count;
6121 }
6122 }
6123 rcu_read_unlock();
6124 break;
6125 }
6126 default:
6127 assert(0);
6128 break;
6129 }
6130
6131 return tot_size;
6132 }
6133
6134 int ust_app_uid_get_channel_runtime_stats(uint64_t ust_session_id,
6135 struct cds_list_head *buffer_reg_uid_list,
6136 struct consumer_output *consumer, uint64_t uchan_id,
6137 int overwrite, uint64_t *discarded, uint64_t *lost)
6138 {
6139 int ret;
6140 uint64_t consumer_chan_key;
6141
6142 *discarded = 0;
6143 *lost = 0;
6144
6145 ret = buffer_reg_uid_consumer_channel_key(
6146 buffer_reg_uid_list, ust_session_id,
6147 uchan_id, &consumer_chan_key);
6148 if (ret < 0) {
6149 /* Not found */
6150 ret = 0;
6151 goto end;
6152 }
6153
6154 if (overwrite) {
6155 ret = consumer_get_lost_packets(ust_session_id,
6156 consumer_chan_key, consumer, lost);
6157 } else {
6158 ret = consumer_get_discarded_events(ust_session_id,
6159 consumer_chan_key, consumer, discarded);
6160 }
6161
6162 end:
6163 return ret;
6164 }
6165
6166 int ust_app_pid_get_channel_runtime_stats(struct ltt_ust_session *usess,
6167 struct ltt_ust_channel *uchan,
6168 struct consumer_output *consumer, int overwrite,
6169 uint64_t *discarded, uint64_t *lost)
6170 {
6171 int ret = 0;
6172 struct lttng_ht_iter iter;
6173 struct lttng_ht_node_str *ua_chan_node;
6174 struct ust_app *app;
6175 struct ust_app_session *ua_sess;
6176 struct ust_app_channel *ua_chan;
6177
6178 *discarded = 0;
6179 *lost = 0;
6180
6181 rcu_read_lock();
6182 /*
6183 * Iterate over every registered applications. Sum counters for
6184 * all applications containing requested session and channel.
6185 */
6186 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
6187 struct lttng_ht_iter uiter;
6188
6189 ua_sess = lookup_session_by_app(usess, app);
6190 if (ua_sess == NULL) {
6191 continue;
6192 }
6193
6194 /* Get channel */
6195 lttng_ht_lookup(ua_sess->channels, (void *) uchan->name, &uiter);
6196 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
6197 /* If the session is found for the app, the channel must be there */
6198 assert(ua_chan_node);
6199
6200 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
6201
6202 if (overwrite) {
6203 uint64_t _lost;
6204
6205 ret = consumer_get_lost_packets(usess->id, ua_chan->key,
6206 consumer, &_lost);
6207 if (ret < 0) {
6208 break;
6209 }
6210 (*lost) += _lost;
6211 } else {
6212 uint64_t _discarded;
6213
6214 ret = consumer_get_discarded_events(usess->id,
6215 ua_chan->key, consumer, &_discarded);
6216 if (ret < 0) {
6217 break;
6218 }
6219 (*discarded) += _discarded;
6220 }
6221 }
6222
6223 rcu_read_unlock();
6224 return ret;
6225 }
6226
6227 static
6228 int ust_app_regenerate_statedump(struct ltt_ust_session *usess,
6229 struct ust_app *app)
6230 {
6231 int ret = 0;
6232 struct ust_app_session *ua_sess;
6233
6234 DBG("Regenerating the metadata for ust app pid %d", app->pid);
6235
6236 rcu_read_lock();
6237
6238 ua_sess = lookup_session_by_app(usess, app);
6239 if (ua_sess == NULL) {
6240 /* The session is in teardown process. Ignore and continue. */
6241 goto end;
6242 }
6243
6244 pthread_mutex_lock(&ua_sess->lock);
6245
6246 if (ua_sess->deleted) {
6247 goto end_unlock;
6248 }
6249
6250 pthread_mutex_lock(&app->sock_lock);
6251 ret = ustctl_regenerate_statedump(app->sock, ua_sess->handle);
6252 pthread_mutex_unlock(&app->sock_lock);
6253
6254 end_unlock:
6255 pthread_mutex_unlock(&ua_sess->lock);
6256
6257 end:
6258 rcu_read_unlock();
6259 health_code_update();
6260 return ret;
6261 }
6262
6263 /*
6264 * Regenerate the statedump for each app in the session.
6265 */
6266 int ust_app_regenerate_statedump_all(struct ltt_ust_session *usess)
6267 {
6268 int ret = 0;
6269 struct lttng_ht_iter iter;
6270 struct ust_app *app;
6271
6272 DBG("Regenerating the metadata for all UST apps");
6273
6274 rcu_read_lock();
6275
6276 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
6277 if (!app->compatible) {
6278 continue;
6279 }
6280
6281 ret = ust_app_regenerate_statedump(usess, app);
6282 if (ret < 0) {
6283 /* Continue to the next app even on error */
6284 continue;
6285 }
6286 }
6287
6288 rcu_read_unlock();
6289
6290 return 0;
6291 }
6292
6293 /*
6294 * Rotate all the channels of a session.
6295 *
6296 * Return 0 on success or else a negative value.
6297 */
6298 int ust_app_rotate_session(struct ltt_session *session, bool *ust_active)
6299 {
6300 int ret = 0;
6301 struct lttng_ht_iter iter;
6302 struct ust_app *app;
6303 struct ltt_ust_session *usess = session->ust_session;
6304 char pathname[LTTNG_PATH_MAX];
6305
6306 assert(usess);
6307
6308 rcu_read_lock();
6309
6310 switch (usess->buffer_type) {
6311 case LTTNG_BUFFER_PER_UID:
6312 {
6313 struct buffer_reg_uid *reg;
6314
6315 cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
6316 struct buffer_reg_channel *reg_chan;
6317 struct consumer_socket *socket;
6318
6319 /* Get consumer socket to use to push the metadata.*/
6320 socket = consumer_find_socket_by_bitness(reg->bits_per_long,
6321 usess->consumer);
6322 if (!socket) {
6323 ret = -EINVAL;
6324 goto error;
6325 }
6326
6327 /*
6328 * Account the metadata channel first to make sure the
6329 * number of channels waiting for a rotation cannot
6330 * reach 0 before we complete the iteration over all
6331 * the channels.
6332 */
6333 ret = rotate_add_channel_pending(
6334 reg->registry->reg.ust->metadata_key,
6335 LTTNG_DOMAIN_UST, session);
6336 if (ret < 0) {
6337 ret = reg->bits_per_long == 32 ?
6338 -LTTNG_ERR_UST_CONSUMER32_FAIL :
6339 -LTTNG_ERR_UST_CONSUMER64_FAIL;
6340 goto error;
6341 }
6342
6343 ret = snprintf(pathname, sizeof(pathname),
6344 DEFAULT_UST_TRACE_DIR "/" DEFAULT_UST_TRACE_UID_PATH,
6345 reg->uid, reg->bits_per_long);
6346 if (ret < 0 || ret == sizeof(pathname)) {
6347 PERROR("Failed to format rotation path");
6348 goto error;
6349 }
6350
6351 /* Rotate the data channels. */
6352 cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter,
6353 reg_chan, node.node) {
6354 ret = rotate_add_channel_pending(
6355 reg_chan->consumer_key,
6356 LTTNG_DOMAIN_UST, session);
6357 if (ret < 0) {
6358 ret = reg->bits_per_long == 32 ?
6359 -LTTNG_ERR_UST_CONSUMER32_FAIL :
6360 -LTTNG_ERR_UST_CONSUMER64_FAIL;
6361 goto error;
6362 }
6363 ret = consumer_rotate_channel(socket,
6364 reg_chan->consumer_key,
6365 usess->uid, usess->gid,
6366 usess->consumer, pathname,
6367 /* is_metadata_channel */ false,
6368 session->current_archive_id,
6369 &session->rotate_pending_relay);
6370 if (ret < 0) {
6371 goto error;
6372 }
6373 }
6374
6375 (void) push_metadata(reg->registry->reg.ust, usess->consumer);
6376
6377 ret = consumer_rotate_channel(socket,
6378 reg->registry->reg.ust->metadata_key,
6379 usess->uid, usess->gid,
6380 usess->consumer, pathname,
6381 /* is_metadata_channel */ true,
6382 session->current_archive_id,
6383 &session->rotate_pending_relay);
6384 if (ret < 0) {
6385 goto error;
6386 }
6387 *ust_active = true;
6388 }
6389 break;
6390 }
6391 case LTTNG_BUFFER_PER_PID:
6392 {
6393 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
6394 struct consumer_socket *socket;
6395 struct lttng_ht_iter chan_iter;
6396 struct ust_app_channel *ua_chan;
6397 struct ust_app_session *ua_sess;
6398 struct ust_registry_session *registry;
6399
6400 ua_sess = lookup_session_by_app(usess, app);
6401 if (!ua_sess) {
6402 /* Session not associated with this app. */
6403 continue;
6404 }
6405 ret = snprintf(pathname, sizeof(pathname),
6406 DEFAULT_UST_TRACE_DIR "/%s",
6407 ua_sess->path);
6408 if (ret < 0 || ret == sizeof(pathname)) {
6409 PERROR("Failed to format rotation path");
6410 goto error;
6411 }
6412
6413 /* Get the right consumer socket for the application. */
6414 socket = consumer_find_socket_by_bitness(app->bits_per_long,
6415 usess->consumer);
6416 if (!socket) {
6417 ret = -EINVAL;
6418 goto error;
6419 }
6420
6421 registry = get_session_registry(ua_sess);
6422 if (!registry) {
6423 DBG("Application session is being torn down. Abort snapshot record.");
6424 ret = -1;
6425 goto error;
6426 }
6427
6428 /*
6429 * Account the metadata channel first to make sure the
6430 * number of channels waiting for a rotation cannot
6431 * reach 0 before we complete the iteration over all
6432 * the channels.
6433 */
6434 ret = rotate_add_channel_pending(registry->metadata_key,
6435 LTTNG_DOMAIN_UST, session);
6436 if (ret < 0) {
6437 ret = app->bits_per_long == 32 ?
6438 -LTTNG_ERR_UST_CONSUMER32_FAIL :
6439 -LTTNG_ERR_UST_CONSUMER64_FAIL;
6440 goto error;
6441 }
6442
6443 /* Rotate the data channels. */
6444 cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter,
6445 ua_chan, node.node) {
6446 ret = rotate_add_channel_pending(
6447 ua_chan->key, LTTNG_DOMAIN_UST,
6448 session);
6449 if (ret < 0) {
6450 ret = app->bits_per_long == 32 ?
6451 -LTTNG_ERR_UST_CONSUMER32_FAIL :
6452 -LTTNG_ERR_UST_CONSUMER64_FAIL;
6453 goto error;
6454 }
6455 ret = consumer_rotate_channel(socket, ua_chan->key,
6456 ua_sess->euid, ua_sess->egid,
6457 ua_sess->consumer, pathname,
6458 /* is_metadata_channel */ false,
6459 session->current_archive_id,
6460 &session->rotate_pending_relay);
6461 if (ret < 0) {
6462 goto error;
6463 }
6464 }
6465
6466 /* Rotate the metadata channel. */
6467 (void) push_metadata(registry, usess->consumer);
6468 ret = consumer_rotate_channel(socket, registry->metadata_key,
6469 ua_sess->euid, ua_sess->egid,
6470 ua_sess->consumer, pathname,
6471 /* is_metadata_channel */ true,
6472 session->current_archive_id,
6473 &session->rotate_pending_relay);
6474 if (ret < 0) {
6475 goto error;
6476 }
6477 *ust_active = true;
6478 }
6479 break;
6480 }
6481 default:
6482 assert(0);
6483 break;
6484 }
6485
6486 ret = LTTNG_OK;
6487
6488 error:
6489 rcu_read_unlock();
6490 return ret;
6491 }
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