17e33a1087dc837593520a2eeb3249267a5096f1
[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
45 static
46 int ust_app_flush_app_session(struct ust_app *app, struct ust_app_session *ua_sess);
47
48 /* Next available channel key. Access under next_channel_key_lock. */
49 static uint64_t _next_channel_key;
50 static pthread_mutex_t next_channel_key_lock = PTHREAD_MUTEX_INITIALIZER;
51
52 /* Next available session ID. Access under next_session_id_lock. */
53 static uint64_t _next_session_id;
54 static pthread_mutex_t next_session_id_lock = PTHREAD_MUTEX_INITIALIZER;
55
56 /*
57 * Return the incremented value of next_channel_key.
58 */
59 static uint64_t get_next_channel_key(void)
60 {
61 uint64_t ret;
62
63 pthread_mutex_lock(&next_channel_key_lock);
64 ret = ++_next_channel_key;
65 pthread_mutex_unlock(&next_channel_key_lock);
66 return ret;
67 }
68
69 /*
70 * Return the atomically incremented value of next_session_id.
71 */
72 static uint64_t get_next_session_id(void)
73 {
74 uint64_t ret;
75
76 pthread_mutex_lock(&next_session_id_lock);
77 ret = ++_next_session_id;
78 pthread_mutex_unlock(&next_session_id_lock);
79 return ret;
80 }
81
82 static void copy_channel_attr_to_ustctl(
83 struct ustctl_consumer_channel_attr *attr,
84 struct lttng_ust_channel_attr *uattr)
85 {
86 /* Copy event attributes since the layout is different. */
87 attr->subbuf_size = uattr->subbuf_size;
88 attr->num_subbuf = uattr->num_subbuf;
89 attr->overwrite = uattr->overwrite;
90 attr->switch_timer_interval = uattr->switch_timer_interval;
91 attr->read_timer_interval = uattr->read_timer_interval;
92 attr->output = uattr->output;
93 }
94
95 /*
96 * Match function for the hash table lookup.
97 *
98 * It matches an ust app event based on three attributes which are the event
99 * name, the filter bytecode and the loglevel.
100 */
101 static int ht_match_ust_app_event(struct cds_lfht_node *node, const void *_key)
102 {
103 struct ust_app_event *event;
104 const struct ust_app_ht_key *key;
105 int ev_loglevel_value;
106
107 assert(node);
108 assert(_key);
109
110 event = caa_container_of(node, struct ust_app_event, node.node);
111 key = _key;
112 ev_loglevel_value = event->attr.loglevel;
113
114 /* Match the 4 elements of the key: name, filter, loglevel, exclusions */
115
116 /* Event name */
117 if (strncmp(event->attr.name, key->name, sizeof(event->attr.name)) != 0) {
118 goto no_match;
119 }
120
121 /* Event loglevel. */
122 if (ev_loglevel_value != key->loglevel_type) {
123 if (event->attr.loglevel_type == LTTNG_UST_LOGLEVEL_ALL
124 && key->loglevel_type == 0 &&
125 ev_loglevel_value == -1) {
126 /*
127 * Match is accepted. This is because on event creation, the
128 * loglevel is set to -1 if the event loglevel type is ALL so 0 and
129 * -1 are accepted for this loglevel type since 0 is the one set by
130 * the API when receiving an enable event.
131 */
132 } else {
133 goto no_match;
134 }
135 }
136
137 /* One of the filters is NULL, fail. */
138 if ((key->filter && !event->filter) || (!key->filter && event->filter)) {
139 goto no_match;
140 }
141
142 if (key->filter && event->filter) {
143 /* Both filters exists, check length followed by the bytecode. */
144 if (event->filter->len != key->filter->len ||
145 memcmp(event->filter->data, key->filter->data,
146 event->filter->len) != 0) {
147 goto no_match;
148 }
149 }
150
151 /* One of the exclusions is NULL, fail. */
152 if ((key->exclusion && !event->exclusion) || (!key->exclusion && event->exclusion)) {
153 goto no_match;
154 }
155
156 if (key->exclusion && event->exclusion) {
157 /* Both exclusions exists, check count followed by the names. */
158 if (event->exclusion->count != key->exclusion->count ||
159 memcmp(event->exclusion->names, key->exclusion->names,
160 event->exclusion->count * LTTNG_UST_SYM_NAME_LEN) != 0) {
161 goto no_match;
162 }
163 }
164
165
166 /* Match. */
167 return 1;
168
169 no_match:
170 return 0;
171 }
172
173 /*
174 * Unique add of an ust app event in the given ht. This uses the custom
175 * ht_match_ust_app_event match function and the event name as hash.
176 */
177 static void add_unique_ust_app_event(struct ust_app_channel *ua_chan,
178 struct ust_app_event *event)
179 {
180 struct cds_lfht_node *node_ptr;
181 struct ust_app_ht_key key;
182 struct lttng_ht *ht;
183
184 assert(ua_chan);
185 assert(ua_chan->events);
186 assert(event);
187
188 ht = ua_chan->events;
189 key.name = event->attr.name;
190 key.filter = event->filter;
191 key.loglevel_type = event->attr.loglevel;
192 key.exclusion = event->exclusion;
193
194 node_ptr = cds_lfht_add_unique(ht->ht,
195 ht->hash_fct(event->node.key, lttng_ht_seed),
196 ht_match_ust_app_event, &key, &event->node.node);
197 assert(node_ptr == &event->node.node);
198 }
199
200 /*
201 * Close the notify socket from the given RCU head object. This MUST be called
202 * through a call_rcu().
203 */
204 static void close_notify_sock_rcu(struct rcu_head *head)
205 {
206 int ret;
207 struct ust_app_notify_sock_obj *obj =
208 caa_container_of(head, struct ust_app_notify_sock_obj, head);
209
210 /* Must have a valid fd here. */
211 assert(obj->fd >= 0);
212
213 ret = close(obj->fd);
214 if (ret) {
215 ERR("close notify sock %d RCU", obj->fd);
216 }
217 lttng_fd_put(LTTNG_FD_APPS, 1);
218
219 free(obj);
220 }
221
222 /*
223 * Return the session registry according to the buffer type of the given
224 * session.
225 *
226 * A registry per UID object MUST exists before calling this function or else
227 * it assert() if not found. RCU read side lock must be acquired.
228 */
229 static struct ust_registry_session *get_session_registry(
230 struct ust_app_session *ua_sess)
231 {
232 struct ust_registry_session *registry = NULL;
233
234 assert(ua_sess);
235
236 switch (ua_sess->buffer_type) {
237 case LTTNG_BUFFER_PER_PID:
238 {
239 struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
240 if (!reg_pid) {
241 goto error;
242 }
243 registry = reg_pid->registry->reg.ust;
244 break;
245 }
246 case LTTNG_BUFFER_PER_UID:
247 {
248 struct buffer_reg_uid *reg_uid = buffer_reg_uid_find(
249 ua_sess->tracing_id, ua_sess->bits_per_long, ua_sess->uid);
250 if (!reg_uid) {
251 goto error;
252 }
253 registry = reg_uid->registry->reg.ust;
254 break;
255 }
256 default:
257 assert(0);
258 };
259
260 error:
261 return registry;
262 }
263
264 /*
265 * Delete ust context safely. RCU read lock must be held before calling
266 * this function.
267 */
268 static
269 void delete_ust_app_ctx(int sock, struct ust_app_ctx *ua_ctx,
270 struct ust_app *app)
271 {
272 int ret;
273
274 assert(ua_ctx);
275
276 if (ua_ctx->obj) {
277 pthread_mutex_lock(&app->sock_lock);
278 ret = ustctl_release_object(sock, ua_ctx->obj);
279 pthread_mutex_unlock(&app->sock_lock);
280 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
281 ERR("UST app sock %d release ctx obj handle %d failed with ret %d",
282 sock, ua_ctx->obj->handle, ret);
283 }
284 free(ua_ctx->obj);
285 }
286 free(ua_ctx);
287 }
288
289 /*
290 * Delete ust app event safely. RCU read lock must be held before calling
291 * this function.
292 */
293 static
294 void delete_ust_app_event(int sock, struct ust_app_event *ua_event,
295 struct ust_app *app)
296 {
297 int ret;
298
299 assert(ua_event);
300
301 free(ua_event->filter);
302 if (ua_event->exclusion != NULL)
303 free(ua_event->exclusion);
304 if (ua_event->obj != NULL) {
305 pthread_mutex_lock(&app->sock_lock);
306 ret = ustctl_release_object(sock, ua_event->obj);
307 pthread_mutex_unlock(&app->sock_lock);
308 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
309 ERR("UST app sock %d release event obj failed with ret %d",
310 sock, ret);
311 }
312 free(ua_event->obj);
313 }
314 free(ua_event);
315 }
316
317 /*
318 * Release ust data object of the given stream.
319 *
320 * Return 0 on success or else a negative value.
321 */
322 static int release_ust_app_stream(int sock, struct ust_app_stream *stream,
323 struct ust_app *app)
324 {
325 int ret = 0;
326
327 assert(stream);
328
329 if (stream->obj) {
330 pthread_mutex_lock(&app->sock_lock);
331 ret = ustctl_release_object(sock, stream->obj);
332 pthread_mutex_unlock(&app->sock_lock);
333 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
334 ERR("UST app sock %d release stream obj failed with ret %d",
335 sock, ret);
336 }
337 lttng_fd_put(LTTNG_FD_APPS, 2);
338 free(stream->obj);
339 }
340
341 return ret;
342 }
343
344 /*
345 * Delete ust app stream safely. RCU read lock must be held before calling
346 * this function.
347 */
348 static
349 void delete_ust_app_stream(int sock, struct ust_app_stream *stream,
350 struct ust_app *app)
351 {
352 assert(stream);
353
354 (void) release_ust_app_stream(sock, stream, app);
355 free(stream);
356 }
357
358 /*
359 * We need to execute ht_destroy outside of RCU read-side critical
360 * section and outside of call_rcu thread, so we postpone its execution
361 * using ht_cleanup_push. It is simpler than to change the semantic of
362 * the many callers of delete_ust_app_session().
363 */
364 static
365 void delete_ust_app_channel_rcu(struct rcu_head *head)
366 {
367 struct ust_app_channel *ua_chan =
368 caa_container_of(head, struct ust_app_channel, rcu_head);
369
370 ht_cleanup_push(ua_chan->ctx);
371 ht_cleanup_push(ua_chan->events);
372 free(ua_chan);
373 }
374
375 /*
376 * Extract the lost packet or discarded events counter when the channel is
377 * being deleted and store the value in the parent channel so we can
378 * access it from lttng list and at stop/destroy.
379 *
380 * The session list lock must be held by the caller.
381 */
382 static
383 void save_per_pid_lost_discarded_counters(struct ust_app_channel *ua_chan)
384 {
385 uint64_t discarded = 0, lost = 0;
386 struct ltt_session *session;
387 struct ltt_ust_channel *uchan;
388
389 if (ua_chan->attr.type != LTTNG_UST_CHAN_PER_CPU) {
390 return;
391 }
392
393 rcu_read_lock();
394 session = session_find_by_id(ua_chan->session->tracing_id);
395 if (!session || !session->ust_session) {
396 /*
397 * Not finding the session is not an error because there are
398 * multiple ways the channels can be torn down.
399 *
400 * 1) The session daemon can initiate the destruction of the
401 * ust app session after receiving a destroy command or
402 * during its shutdown/teardown.
403 * 2) The application, since we are in per-pid tracing, is
404 * unregistering and tearing down its ust app session.
405 *
406 * Both paths are protected by the session list lock which
407 * ensures that the accounting of lost packets and discarded
408 * events is done exactly once. The session is then unpublished
409 * from the session list, resulting in this condition.
410 */
411 goto end;
412 }
413
414 if (ua_chan->attr.overwrite) {
415 consumer_get_lost_packets(ua_chan->session->tracing_id,
416 ua_chan->key, session->ust_session->consumer,
417 &lost);
418 } else {
419 consumer_get_discarded_events(ua_chan->session->tracing_id,
420 ua_chan->key, session->ust_session->consumer,
421 &discarded);
422 }
423 uchan = trace_ust_find_channel_by_name(
424 session->ust_session->domain_global.channels,
425 ua_chan->name);
426 if (!uchan) {
427 ERR("Missing UST channel to store discarded counters");
428 goto end;
429 }
430
431 uchan->per_pid_closed_app_discarded += discarded;
432 uchan->per_pid_closed_app_lost += lost;
433
434 end:
435 rcu_read_unlock();
436 }
437
438 /*
439 * Delete ust app channel safely. RCU read lock must be held before calling
440 * this function.
441 *
442 * The session list lock must be held by the caller.
443 */
444 static
445 void delete_ust_app_channel(int sock, struct ust_app_channel *ua_chan,
446 struct ust_app *app)
447 {
448 int ret;
449 struct lttng_ht_iter iter;
450 struct ust_app_event *ua_event;
451 struct ust_app_ctx *ua_ctx;
452 struct ust_app_stream *stream, *stmp;
453 struct ust_registry_session *registry;
454
455 assert(ua_chan);
456
457 DBG3("UST app deleting channel %s", ua_chan->name);
458
459 /* Wipe stream */
460 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
461 cds_list_del(&stream->list);
462 delete_ust_app_stream(sock, stream, app);
463 }
464
465 /* Wipe context */
466 cds_lfht_for_each_entry(ua_chan->ctx->ht, &iter.iter, ua_ctx, node.node) {
467 cds_list_del(&ua_ctx->list);
468 ret = lttng_ht_del(ua_chan->ctx, &iter);
469 assert(!ret);
470 delete_ust_app_ctx(sock, ua_ctx, app);
471 }
472
473 /* Wipe events */
474 cds_lfht_for_each_entry(ua_chan->events->ht, &iter.iter, ua_event,
475 node.node) {
476 ret = lttng_ht_del(ua_chan->events, &iter);
477 assert(!ret);
478 delete_ust_app_event(sock, ua_event, app);
479 }
480
481 if (ua_chan->session->buffer_type == LTTNG_BUFFER_PER_PID) {
482 /* Wipe and free registry from session registry. */
483 registry = get_session_registry(ua_chan->session);
484 if (registry) {
485 ust_registry_channel_del_free(registry, ua_chan->key);
486 }
487 save_per_pid_lost_discarded_counters(ua_chan);
488 }
489
490 if (ua_chan->obj != NULL) {
491 /* Remove channel from application UST object descriptor. */
492 iter.iter.node = &ua_chan->ust_objd_node.node;
493 ret = lttng_ht_del(app->ust_objd, &iter);
494 assert(!ret);
495 pthread_mutex_lock(&app->sock_lock);
496 ret = ustctl_release_object(sock, ua_chan->obj);
497 pthread_mutex_unlock(&app->sock_lock);
498 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
499 ERR("UST app sock %d release channel obj failed with ret %d",
500 sock, ret);
501 }
502 lttng_fd_put(LTTNG_FD_APPS, 1);
503 free(ua_chan->obj);
504 }
505 call_rcu(&ua_chan->rcu_head, delete_ust_app_channel_rcu);
506 }
507
508 int ust_app_register_done(struct ust_app *app)
509 {
510 int ret;
511
512 pthread_mutex_lock(&app->sock_lock);
513 ret = ustctl_register_done(app->sock);
514 pthread_mutex_unlock(&app->sock_lock);
515 return ret;
516 }
517
518 int ust_app_release_object(struct ust_app *app, struct lttng_ust_object_data *data)
519 {
520 int ret, sock;
521
522 if (app) {
523 pthread_mutex_lock(&app->sock_lock);
524 sock = app->sock;
525 } else {
526 sock = -1;
527 }
528 ret = ustctl_release_object(sock, data);
529 if (app) {
530 pthread_mutex_unlock(&app->sock_lock);
531 }
532 return ret;
533 }
534
535 /*
536 * Push metadata to consumer socket.
537 *
538 * RCU read-side lock must be held to guarantee existance of socket.
539 * Must be called with the ust app session lock held.
540 * Must be called with the registry lock held.
541 *
542 * On success, return the len of metadata pushed or else a negative value.
543 * Returning a -EPIPE return value means we could not send the metadata,
544 * but it can be caused by recoverable errors (e.g. the application has
545 * terminated concurrently).
546 */
547 ssize_t ust_app_push_metadata(struct ust_registry_session *registry,
548 struct consumer_socket *socket, int send_zero_data)
549 {
550 int ret;
551 char *metadata_str = NULL;
552 size_t len, offset, new_metadata_len_sent;
553 ssize_t ret_val;
554 uint64_t metadata_key, metadata_version;
555
556 assert(registry);
557 assert(socket);
558
559 metadata_key = registry->metadata_key;
560
561 /*
562 * Means that no metadata was assigned to the session. This can
563 * happens if no start has been done previously.
564 */
565 if (!metadata_key) {
566 return 0;
567 }
568
569 /*
570 * On a push metadata error either the consumer is dead or the
571 * metadata channel has been destroyed because its endpoint
572 * might have died (e.g: relayd), or because the application has
573 * exited. If so, the metadata closed flag is set to 1 so we
574 * deny pushing metadata again which is not valid anymore on the
575 * consumer side.
576 */
577 if (registry->metadata_closed) {
578 return -EPIPE;
579 }
580
581 offset = registry->metadata_len_sent;
582 len = registry->metadata_len - registry->metadata_len_sent;
583 new_metadata_len_sent = registry->metadata_len;
584 metadata_version = registry->metadata_version;
585 if (len == 0) {
586 DBG3("No metadata to push for metadata key %" PRIu64,
587 registry->metadata_key);
588 ret_val = len;
589 if (send_zero_data) {
590 DBG("No metadata to push");
591 goto push_data;
592 }
593 goto end;
594 }
595
596 /* Allocate only what we have to send. */
597 metadata_str = zmalloc(len);
598 if (!metadata_str) {
599 PERROR("zmalloc ust app metadata string");
600 ret_val = -ENOMEM;
601 goto error;
602 }
603 /* Copy what we haven't sent out. */
604 memcpy(metadata_str, registry->metadata + offset, len);
605
606 push_data:
607 pthread_mutex_unlock(&registry->lock);
608 /*
609 * We need to unlock the registry while we push metadata to
610 * break a circular dependency between the consumerd metadata
611 * lock and the sessiond registry lock. Indeed, pushing metadata
612 * to the consumerd awaits that it gets pushed all the way to
613 * relayd, but doing so requires grabbing the metadata lock. If
614 * a concurrent metadata request is being performed by
615 * consumerd, this can try to grab the registry lock on the
616 * sessiond while holding the metadata lock on the consumer
617 * daemon. Those push and pull schemes are performed on two
618 * different bidirectionnal communication sockets.
619 */
620 ret = consumer_push_metadata(socket, metadata_key,
621 metadata_str, len, offset, metadata_version);
622 pthread_mutex_lock(&registry->lock);
623 if (ret < 0) {
624 /*
625 * There is an acceptable race here between the registry
626 * metadata key assignment and the creation on the
627 * consumer. The session daemon can concurrently push
628 * metadata for this registry while being created on the
629 * consumer since the metadata key of the registry is
630 * assigned *before* it is setup to avoid the consumer
631 * to ask for metadata that could possibly be not found
632 * in the session daemon.
633 *
634 * The metadata will get pushed either by the session
635 * being stopped or the consumer requesting metadata if
636 * that race is triggered.
637 */
638 if (ret == -LTTCOMM_CONSUMERD_CHANNEL_FAIL) {
639 ret = 0;
640 } else {
641 ERR("Error pushing metadata to consumer");
642 }
643 ret_val = ret;
644 goto error_push;
645 } else {
646 /*
647 * Metadata may have been concurrently pushed, since
648 * we're not holding the registry lock while pushing to
649 * consumer. This is handled by the fact that we send
650 * the metadata content, size, and the offset at which
651 * that metadata belongs. This may arrive out of order
652 * on the consumer side, and the consumer is able to
653 * deal with overlapping fragments. The consumer
654 * supports overlapping fragments, which must be
655 * contiguous starting from offset 0. We keep the
656 * largest metadata_len_sent value of the concurrent
657 * send.
658 */
659 registry->metadata_len_sent =
660 max_t(size_t, registry->metadata_len_sent,
661 new_metadata_len_sent);
662 }
663 free(metadata_str);
664 return len;
665
666 end:
667 error:
668 if (ret_val) {
669 /*
670 * On error, flag the registry that the metadata is
671 * closed. We were unable to push anything and this
672 * means that either the consumer is not responding or
673 * the metadata cache has been destroyed on the
674 * consumer.
675 */
676 registry->metadata_closed = 1;
677 }
678 error_push:
679 free(metadata_str);
680 return ret_val;
681 }
682
683 /*
684 * For a given application and session, push metadata to consumer.
685 * Either sock or consumer is required : if sock is NULL, the default
686 * socket to send the metadata is retrieved from consumer, if sock
687 * is not NULL we use it to send the metadata.
688 * RCU read-side lock must be held while calling this function,
689 * therefore ensuring existance of registry. It also ensures existance
690 * of socket throughout this function.
691 *
692 * Return 0 on success else a negative error.
693 * Returning a -EPIPE return value means we could not send the metadata,
694 * but it can be caused by recoverable errors (e.g. the application has
695 * terminated concurrently).
696 */
697 static int push_metadata(struct ust_registry_session *registry,
698 struct consumer_output *consumer)
699 {
700 int ret_val;
701 ssize_t ret;
702 struct consumer_socket *socket;
703
704 assert(registry);
705 assert(consumer);
706
707 pthread_mutex_lock(&registry->lock);
708 if (registry->metadata_closed) {
709 ret_val = -EPIPE;
710 goto error;
711 }
712
713 /* Get consumer socket to use to push the metadata.*/
714 socket = consumer_find_socket_by_bitness(registry->bits_per_long,
715 consumer);
716 if (!socket) {
717 ret_val = -1;
718 goto error;
719 }
720
721 ret = ust_app_push_metadata(registry, socket, 0);
722 if (ret < 0) {
723 ret_val = ret;
724 goto error;
725 }
726 pthread_mutex_unlock(&registry->lock);
727 return 0;
728
729 error:
730 pthread_mutex_unlock(&registry->lock);
731 return ret_val;
732 }
733
734 /*
735 * Send to the consumer a close metadata command for the given session. Once
736 * done, the metadata channel is deleted and the session metadata pointer is
737 * nullified. The session lock MUST be held unless the application is
738 * in the destroy path.
739 *
740 * Return 0 on success else a negative value.
741 */
742 static int close_metadata(struct ust_registry_session *registry,
743 struct consumer_output *consumer)
744 {
745 int ret;
746 struct consumer_socket *socket;
747
748 assert(registry);
749 assert(consumer);
750
751 rcu_read_lock();
752
753 pthread_mutex_lock(&registry->lock);
754
755 if (!registry->metadata_key || registry->metadata_closed) {
756 ret = 0;
757 goto end;
758 }
759
760 /* Get consumer socket to use to push the metadata.*/
761 socket = consumer_find_socket_by_bitness(registry->bits_per_long,
762 consumer);
763 if (!socket) {
764 ret = -1;
765 goto error;
766 }
767
768 ret = consumer_close_metadata(socket, registry->metadata_key);
769 if (ret < 0) {
770 goto error;
771 }
772
773 error:
774 /*
775 * Metadata closed. Even on error this means that the consumer is not
776 * responding or not found so either way a second close should NOT be emit
777 * for this registry.
778 */
779 registry->metadata_closed = 1;
780 end:
781 pthread_mutex_unlock(&registry->lock);
782 rcu_read_unlock();
783 return ret;
784 }
785
786 /*
787 * We need to execute ht_destroy outside of RCU read-side critical
788 * section and outside of call_rcu thread, so we postpone its execution
789 * using ht_cleanup_push. It is simpler than to change the semantic of
790 * the many callers of delete_ust_app_session().
791 */
792 static
793 void delete_ust_app_session_rcu(struct rcu_head *head)
794 {
795 struct ust_app_session *ua_sess =
796 caa_container_of(head, struct ust_app_session, rcu_head);
797
798 ht_cleanup_push(ua_sess->channels);
799 free(ua_sess);
800 }
801
802 /*
803 * Delete ust app session safely. RCU read lock must be held before calling
804 * this function.
805 *
806 * The session list lock must be held by the caller.
807 */
808 static
809 void delete_ust_app_session(int sock, struct ust_app_session *ua_sess,
810 struct ust_app *app)
811 {
812 int ret;
813 struct lttng_ht_iter iter;
814 struct ust_app_channel *ua_chan;
815 struct ust_registry_session *registry;
816
817 assert(ua_sess);
818
819 pthread_mutex_lock(&ua_sess->lock);
820
821 assert(!ua_sess->deleted);
822 ua_sess->deleted = true;
823
824 registry = get_session_registry(ua_sess);
825 if (registry) {
826 /* Push metadata for application before freeing the application. */
827 (void) push_metadata(registry, ua_sess->consumer);
828
829 /*
830 * Don't ask to close metadata for global per UID buffers. Close
831 * metadata only on destroy trace session in this case. Also, the
832 * previous push metadata could have flag the metadata registry to
833 * close so don't send a close command if closed.
834 */
835 if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID) {
836 /* And ask to close it for this session registry. */
837 (void) close_metadata(registry, ua_sess->consumer);
838 }
839 }
840
841 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
842 node.node) {
843 ret = lttng_ht_del(ua_sess->channels, &iter);
844 assert(!ret);
845 delete_ust_app_channel(sock, ua_chan, app);
846 }
847
848 /* In case of per PID, the registry is kept in the session. */
849 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) {
850 struct buffer_reg_pid *reg_pid = buffer_reg_pid_find(ua_sess->id);
851 if (reg_pid) {
852 buffer_reg_pid_remove(reg_pid);
853 buffer_reg_pid_destroy(reg_pid);
854 }
855 }
856
857 if (ua_sess->handle != -1) {
858 pthread_mutex_lock(&app->sock_lock);
859 ret = ustctl_release_handle(sock, ua_sess->handle);
860 pthread_mutex_unlock(&app->sock_lock);
861 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
862 ERR("UST app sock %d release session handle failed with ret %d",
863 sock, ret);
864 }
865 /* Remove session from application UST object descriptor. */
866 iter.iter.node = &ua_sess->ust_objd_node.node;
867 ret = lttng_ht_del(app->ust_sessions_objd, &iter);
868 assert(!ret);
869 }
870
871 pthread_mutex_unlock(&ua_sess->lock);
872
873 consumer_output_put(ua_sess->consumer);
874
875 call_rcu(&ua_sess->rcu_head, delete_ust_app_session_rcu);
876 }
877
878 /*
879 * Delete a traceable application structure from the global list. Never call
880 * this function outside of a call_rcu call.
881 *
882 * RCU read side lock should _NOT_ be held when calling this function.
883 */
884 static
885 void delete_ust_app(struct ust_app *app)
886 {
887 int ret, sock;
888 struct ust_app_session *ua_sess, *tmp_ua_sess;
889
890 /*
891 * The session list lock must be held during this function to guarantee
892 * the existence of ua_sess.
893 */
894 session_lock_list();
895 /* Delete ust app sessions info */
896 sock = app->sock;
897 app->sock = -1;
898
899 /* Wipe sessions */
900 cds_list_for_each_entry_safe(ua_sess, tmp_ua_sess, &app->teardown_head,
901 teardown_node) {
902 /* Free every object in the session and the session. */
903 rcu_read_lock();
904 delete_ust_app_session(sock, ua_sess, app);
905 rcu_read_unlock();
906 }
907
908 ht_cleanup_push(app->sessions);
909 ht_cleanup_push(app->ust_sessions_objd);
910 ht_cleanup_push(app->ust_objd);
911
912 /*
913 * Wait until we have deleted the application from the sock hash table
914 * before closing this socket, otherwise an application could re-use the
915 * socket ID and race with the teardown, using the same hash table entry.
916 *
917 * It's OK to leave the close in call_rcu. We want it to stay unique for
918 * all RCU readers that could run concurrently with unregister app,
919 * therefore we _need_ to only close that socket after a grace period. So
920 * it should stay in this RCU callback.
921 *
922 * This close() is a very important step of the synchronization model so
923 * every modification to this function must be carefully reviewed.
924 */
925 ret = close(sock);
926 if (ret) {
927 PERROR("close");
928 }
929 lttng_fd_put(LTTNG_FD_APPS, 1);
930
931 DBG2("UST app pid %d deleted", app->pid);
932 free(app);
933 session_unlock_list();
934 }
935
936 /*
937 * URCU intermediate call to delete an UST app.
938 */
939 static
940 void delete_ust_app_rcu(struct rcu_head *head)
941 {
942 struct lttng_ht_node_ulong *node =
943 caa_container_of(head, struct lttng_ht_node_ulong, head);
944 struct ust_app *app =
945 caa_container_of(node, struct ust_app, pid_n);
946
947 DBG3("Call RCU deleting app PID %d", app->pid);
948 delete_ust_app(app);
949 }
950
951 /*
952 * Delete the session from the application ht and delete the data structure by
953 * freeing every object inside and releasing them.
954 *
955 * The session list lock must be held by the caller.
956 */
957 static void destroy_app_session(struct ust_app *app,
958 struct ust_app_session *ua_sess)
959 {
960 int ret;
961 struct lttng_ht_iter iter;
962
963 assert(app);
964 assert(ua_sess);
965
966 iter.iter.node = &ua_sess->node.node;
967 ret = lttng_ht_del(app->sessions, &iter);
968 if (ret) {
969 /* Already scheduled for teardown. */
970 goto end;
971 }
972
973 /* Once deleted, free the data structure. */
974 delete_ust_app_session(app->sock, ua_sess, app);
975
976 end:
977 return;
978 }
979
980 /*
981 * Alloc new UST app session.
982 */
983 static
984 struct ust_app_session *alloc_ust_app_session(struct ust_app *app)
985 {
986 struct ust_app_session *ua_sess;
987
988 /* Init most of the default value by allocating and zeroing */
989 ua_sess = zmalloc(sizeof(struct ust_app_session));
990 if (ua_sess == NULL) {
991 PERROR("malloc");
992 goto error_free;
993 }
994
995 ua_sess->handle = -1;
996 ua_sess->channels = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
997 ua_sess->metadata_attr.type = LTTNG_UST_CHAN_METADATA;
998 pthread_mutex_init(&ua_sess->lock, NULL);
999
1000 return ua_sess;
1001
1002 error_free:
1003 return NULL;
1004 }
1005
1006 /*
1007 * Alloc new UST app channel.
1008 */
1009 static
1010 struct ust_app_channel *alloc_ust_app_channel(char *name,
1011 struct ust_app_session *ua_sess,
1012 struct lttng_ust_channel_attr *attr)
1013 {
1014 struct ust_app_channel *ua_chan;
1015
1016 /* Init most of the default value by allocating and zeroing */
1017 ua_chan = zmalloc(sizeof(struct ust_app_channel));
1018 if (ua_chan == NULL) {
1019 PERROR("malloc");
1020 goto error;
1021 }
1022
1023 /* Setup channel name */
1024 strncpy(ua_chan->name, name, sizeof(ua_chan->name));
1025 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
1026
1027 ua_chan->enabled = 1;
1028 ua_chan->handle = -1;
1029 ua_chan->session = ua_sess;
1030 ua_chan->key = get_next_channel_key();
1031 ua_chan->ctx = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
1032 ua_chan->events = lttng_ht_new(0, LTTNG_HT_TYPE_STRING);
1033 lttng_ht_node_init_str(&ua_chan->node, ua_chan->name);
1034
1035 CDS_INIT_LIST_HEAD(&ua_chan->streams.head);
1036 CDS_INIT_LIST_HEAD(&ua_chan->ctx_list);
1037
1038 /* Copy attributes */
1039 if (attr) {
1040 /* Translate from lttng_ust_channel to ustctl_consumer_channel_attr. */
1041 ua_chan->attr.subbuf_size = attr->subbuf_size;
1042 ua_chan->attr.num_subbuf = attr->num_subbuf;
1043 ua_chan->attr.overwrite = attr->overwrite;
1044 ua_chan->attr.switch_timer_interval = attr->switch_timer_interval;
1045 ua_chan->attr.read_timer_interval = attr->read_timer_interval;
1046 ua_chan->attr.output = attr->output;
1047 }
1048 /* By default, the channel is a per cpu channel. */
1049 ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
1050
1051 DBG3("UST app channel %s allocated", ua_chan->name);
1052
1053 return ua_chan;
1054
1055 error:
1056 return NULL;
1057 }
1058
1059 /*
1060 * Allocate and initialize a UST app stream.
1061 *
1062 * Return newly allocated stream pointer or NULL on error.
1063 */
1064 struct ust_app_stream *ust_app_alloc_stream(void)
1065 {
1066 struct ust_app_stream *stream = NULL;
1067
1068 stream = zmalloc(sizeof(*stream));
1069 if (stream == NULL) {
1070 PERROR("zmalloc ust app stream");
1071 goto error;
1072 }
1073
1074 /* Zero could be a valid value for a handle so flag it to -1. */
1075 stream->handle = -1;
1076
1077 error:
1078 return stream;
1079 }
1080
1081 /*
1082 * Alloc new UST app event.
1083 */
1084 static
1085 struct ust_app_event *alloc_ust_app_event(char *name,
1086 struct lttng_ust_event *attr)
1087 {
1088 struct ust_app_event *ua_event;
1089
1090 /* Init most of the default value by allocating and zeroing */
1091 ua_event = zmalloc(sizeof(struct ust_app_event));
1092 if (ua_event == NULL) {
1093 PERROR("malloc");
1094 goto error;
1095 }
1096
1097 ua_event->enabled = 1;
1098 strncpy(ua_event->name, name, sizeof(ua_event->name));
1099 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
1100 lttng_ht_node_init_str(&ua_event->node, ua_event->name);
1101
1102 /* Copy attributes */
1103 if (attr) {
1104 memcpy(&ua_event->attr, attr, sizeof(ua_event->attr));
1105 }
1106
1107 DBG3("UST app event %s allocated", ua_event->name);
1108
1109 return ua_event;
1110
1111 error:
1112 return NULL;
1113 }
1114
1115 /*
1116 * Alloc new UST app context.
1117 */
1118 static
1119 struct ust_app_ctx *alloc_ust_app_ctx(struct lttng_ust_context_attr *uctx)
1120 {
1121 struct ust_app_ctx *ua_ctx;
1122
1123 ua_ctx = zmalloc(sizeof(struct ust_app_ctx));
1124 if (ua_ctx == NULL) {
1125 goto error;
1126 }
1127
1128 CDS_INIT_LIST_HEAD(&ua_ctx->list);
1129
1130 if (uctx) {
1131 memcpy(&ua_ctx->ctx, uctx, sizeof(ua_ctx->ctx));
1132 if (uctx->ctx == LTTNG_UST_CONTEXT_APP_CONTEXT) {
1133 char *provider_name = NULL, *ctx_name = NULL;
1134
1135 provider_name = strdup(uctx->u.app_ctx.provider_name);
1136 ctx_name = strdup(uctx->u.app_ctx.ctx_name);
1137 if (!provider_name || !ctx_name) {
1138 free(provider_name);
1139 free(ctx_name);
1140 goto error;
1141 }
1142
1143 ua_ctx->ctx.u.app_ctx.provider_name = provider_name;
1144 ua_ctx->ctx.u.app_ctx.ctx_name = ctx_name;
1145 }
1146 }
1147
1148 DBG3("UST app context %d allocated", ua_ctx->ctx.ctx);
1149 return ua_ctx;
1150 error:
1151 free(ua_ctx);
1152 return NULL;
1153 }
1154
1155 /*
1156 * Allocate a filter and copy the given original filter.
1157 *
1158 * Return allocated filter or NULL on error.
1159 */
1160 static struct lttng_filter_bytecode *copy_filter_bytecode(
1161 struct lttng_filter_bytecode *orig_f)
1162 {
1163 struct lttng_filter_bytecode *filter = NULL;
1164
1165 /* Copy filter bytecode */
1166 filter = zmalloc(sizeof(*filter) + orig_f->len);
1167 if (!filter) {
1168 PERROR("zmalloc alloc filter bytecode");
1169 goto error;
1170 }
1171
1172 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
1173
1174 error:
1175 return filter;
1176 }
1177
1178 /*
1179 * Create a liblttng-ust filter bytecode from given bytecode.
1180 *
1181 * Return allocated filter or NULL on error.
1182 */
1183 static struct lttng_ust_filter_bytecode *create_ust_bytecode_from_bytecode(
1184 struct lttng_filter_bytecode *orig_f)
1185 {
1186 struct lttng_ust_filter_bytecode *filter = NULL;
1187
1188 /* Copy filter bytecode */
1189 filter = zmalloc(sizeof(*filter) + orig_f->len);
1190 if (!filter) {
1191 PERROR("zmalloc alloc ust filter bytecode");
1192 goto error;
1193 }
1194
1195 assert(sizeof(struct lttng_filter_bytecode) ==
1196 sizeof(struct lttng_ust_filter_bytecode));
1197 memcpy(filter, orig_f, sizeof(*filter) + orig_f->len);
1198 error:
1199 return filter;
1200 }
1201
1202 /*
1203 * Find an ust_app using the sock and return it. RCU read side lock must be
1204 * held before calling this helper function.
1205 */
1206 struct ust_app *ust_app_find_by_sock(int sock)
1207 {
1208 struct lttng_ht_node_ulong *node;
1209 struct lttng_ht_iter iter;
1210
1211 lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &iter);
1212 node = lttng_ht_iter_get_node_ulong(&iter);
1213 if (node == NULL) {
1214 DBG2("UST app find by sock %d not found", sock);
1215 goto error;
1216 }
1217
1218 return caa_container_of(node, struct ust_app, sock_n);
1219
1220 error:
1221 return NULL;
1222 }
1223
1224 /*
1225 * Find an ust_app using the notify sock and return it. RCU read side lock must
1226 * be held before calling this helper function.
1227 */
1228 static struct ust_app *find_app_by_notify_sock(int sock)
1229 {
1230 struct lttng_ht_node_ulong *node;
1231 struct lttng_ht_iter iter;
1232
1233 lttng_ht_lookup(ust_app_ht_by_notify_sock, (void *)((unsigned long) sock),
1234 &iter);
1235 node = lttng_ht_iter_get_node_ulong(&iter);
1236 if (node == NULL) {
1237 DBG2("UST app find by notify sock %d not found", sock);
1238 goto error;
1239 }
1240
1241 return caa_container_of(node, struct ust_app, notify_sock_n);
1242
1243 error:
1244 return NULL;
1245 }
1246
1247 /*
1248 * Lookup for an ust app event based on event name, filter bytecode and the
1249 * event loglevel.
1250 *
1251 * Return an ust_app_event object or NULL on error.
1252 */
1253 static struct ust_app_event *find_ust_app_event(struct lttng_ht *ht,
1254 char *name, struct lttng_filter_bytecode *filter,
1255 int loglevel_value,
1256 const struct lttng_event_exclusion *exclusion)
1257 {
1258 struct lttng_ht_iter iter;
1259 struct lttng_ht_node_str *node;
1260 struct ust_app_event *event = NULL;
1261 struct ust_app_ht_key key;
1262
1263 assert(name);
1264 assert(ht);
1265
1266 /* Setup key for event lookup. */
1267 key.name = name;
1268 key.filter = filter;
1269 key.loglevel_type = loglevel_value;
1270 /* lttng_event_exclusion and lttng_ust_event_exclusion structures are similar */
1271 key.exclusion = exclusion;
1272
1273 /* Lookup using the event name as hash and a custom match fct. */
1274 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) name, lttng_ht_seed),
1275 ht_match_ust_app_event, &key, &iter.iter);
1276 node = lttng_ht_iter_get_node_str(&iter);
1277 if (node == NULL) {
1278 goto end;
1279 }
1280
1281 event = caa_container_of(node, struct ust_app_event, node);
1282
1283 end:
1284 return event;
1285 }
1286
1287 /*
1288 * Create the channel context on the tracer.
1289 *
1290 * Called with UST app session lock held.
1291 */
1292 static
1293 int create_ust_channel_context(struct ust_app_channel *ua_chan,
1294 struct ust_app_ctx *ua_ctx, struct ust_app *app)
1295 {
1296 int ret;
1297
1298 health_code_update();
1299
1300 pthread_mutex_lock(&app->sock_lock);
1301 ret = ustctl_add_context(app->sock, &ua_ctx->ctx,
1302 ua_chan->obj, &ua_ctx->obj);
1303 pthread_mutex_unlock(&app->sock_lock);
1304 if (ret < 0) {
1305 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1306 ERR("UST app create channel context failed for app (pid: %d) "
1307 "with ret %d", app->pid, ret);
1308 } else {
1309 /*
1310 * This is normal behavior, an application can die during the
1311 * creation process. Don't report an error so the execution can
1312 * continue normally.
1313 */
1314 ret = 0;
1315 DBG3("UST app disable event failed. Application is dead.");
1316 }
1317 goto error;
1318 }
1319
1320 ua_ctx->handle = ua_ctx->obj->handle;
1321
1322 DBG2("UST app context handle %d created successfully for channel %s",
1323 ua_ctx->handle, ua_chan->name);
1324
1325 error:
1326 health_code_update();
1327 return ret;
1328 }
1329
1330 /*
1331 * Set the filter on the tracer.
1332 */
1333 static
1334 int set_ust_event_filter(struct ust_app_event *ua_event,
1335 struct ust_app *app)
1336 {
1337 int ret;
1338 struct lttng_ust_filter_bytecode *ust_bytecode = NULL;
1339
1340 health_code_update();
1341
1342 if (!ua_event->filter) {
1343 ret = 0;
1344 goto error;
1345 }
1346
1347 ust_bytecode = create_ust_bytecode_from_bytecode(ua_event->filter);
1348 if (!ust_bytecode) {
1349 ret = -LTTNG_ERR_NOMEM;
1350 goto error;
1351 }
1352 pthread_mutex_lock(&app->sock_lock);
1353 ret = ustctl_set_filter(app->sock, ust_bytecode,
1354 ua_event->obj);
1355 pthread_mutex_unlock(&app->sock_lock);
1356 if (ret < 0) {
1357 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1358 ERR("UST app event %s filter failed for app (pid: %d) "
1359 "with ret %d", ua_event->attr.name, app->pid, ret);
1360 } else {
1361 /*
1362 * This is normal behavior, an application can die during the
1363 * creation process. Don't report an error so the execution can
1364 * continue normally.
1365 */
1366 ret = 0;
1367 DBG3("UST app filter event failed. Application is dead.");
1368 }
1369 goto error;
1370 }
1371
1372 DBG2("UST filter set successfully for event %s", ua_event->name);
1373
1374 error:
1375 health_code_update();
1376 free(ust_bytecode);
1377 return ret;
1378 }
1379
1380 static
1381 struct lttng_ust_event_exclusion *create_ust_exclusion_from_exclusion(
1382 struct lttng_event_exclusion *exclusion)
1383 {
1384 struct lttng_ust_event_exclusion *ust_exclusion = NULL;
1385 size_t exclusion_alloc_size = sizeof(struct lttng_ust_event_exclusion) +
1386 LTTNG_UST_SYM_NAME_LEN * exclusion->count;
1387
1388 ust_exclusion = zmalloc(exclusion_alloc_size);
1389 if (!ust_exclusion) {
1390 PERROR("malloc");
1391 goto end;
1392 }
1393
1394 assert(sizeof(struct lttng_event_exclusion) ==
1395 sizeof(struct lttng_ust_event_exclusion));
1396 memcpy(ust_exclusion, exclusion, exclusion_alloc_size);
1397 end:
1398 return ust_exclusion;
1399 }
1400
1401 /*
1402 * Set event exclusions on the tracer.
1403 */
1404 static
1405 int set_ust_event_exclusion(struct ust_app_event *ua_event,
1406 struct ust_app *app)
1407 {
1408 int ret;
1409 struct lttng_ust_event_exclusion *ust_exclusion = NULL;
1410
1411 health_code_update();
1412
1413 if (!ua_event->exclusion || !ua_event->exclusion->count) {
1414 ret = 0;
1415 goto error;
1416 }
1417
1418 ust_exclusion = create_ust_exclusion_from_exclusion(
1419 ua_event->exclusion);
1420 if (!ust_exclusion) {
1421 ret = -LTTNG_ERR_NOMEM;
1422 goto error;
1423 }
1424 pthread_mutex_lock(&app->sock_lock);
1425 ret = ustctl_set_exclusion(app->sock, ust_exclusion, ua_event->obj);
1426 pthread_mutex_unlock(&app->sock_lock);
1427 if (ret < 0) {
1428 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1429 ERR("UST app event %s exclusions failed for app (pid: %d) "
1430 "with ret %d", ua_event->attr.name, app->pid, ret);
1431 } else {
1432 /*
1433 * This is normal behavior, an application can die during the
1434 * creation process. Don't report an error so the execution can
1435 * continue normally.
1436 */
1437 ret = 0;
1438 DBG3("UST app event exclusion failed. Application is dead.");
1439 }
1440 goto error;
1441 }
1442
1443 DBG2("UST exclusion set successfully for event %s", ua_event->name);
1444
1445 error:
1446 health_code_update();
1447 free(ust_exclusion);
1448 return ret;
1449 }
1450
1451 /*
1452 * Disable the specified event on to UST tracer for the UST session.
1453 */
1454 static int disable_ust_event(struct ust_app *app,
1455 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
1456 {
1457 int ret;
1458
1459 health_code_update();
1460
1461 pthread_mutex_lock(&app->sock_lock);
1462 ret = ustctl_disable(app->sock, ua_event->obj);
1463 pthread_mutex_unlock(&app->sock_lock);
1464 if (ret < 0) {
1465 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1466 ERR("UST app event %s disable failed for app (pid: %d) "
1467 "and session handle %d with ret %d",
1468 ua_event->attr.name, app->pid, ua_sess->handle, ret);
1469 } else {
1470 /*
1471 * This is normal behavior, an application can die during the
1472 * creation process. Don't report an error so the execution can
1473 * continue normally.
1474 */
1475 ret = 0;
1476 DBG3("UST app disable event failed. Application is dead.");
1477 }
1478 goto error;
1479 }
1480
1481 DBG2("UST app event %s disabled successfully for app (pid: %d)",
1482 ua_event->attr.name, app->pid);
1483
1484 error:
1485 health_code_update();
1486 return ret;
1487 }
1488
1489 /*
1490 * Disable the specified channel on to UST tracer for the UST session.
1491 */
1492 static int disable_ust_channel(struct ust_app *app,
1493 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1494 {
1495 int ret;
1496
1497 health_code_update();
1498
1499 pthread_mutex_lock(&app->sock_lock);
1500 ret = ustctl_disable(app->sock, ua_chan->obj);
1501 pthread_mutex_unlock(&app->sock_lock);
1502 if (ret < 0) {
1503 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1504 ERR("UST app channel %s disable failed for app (pid: %d) "
1505 "and session handle %d with ret %d",
1506 ua_chan->name, app->pid, ua_sess->handle, ret);
1507 } else {
1508 /*
1509 * This is normal behavior, an application can die during the
1510 * creation process. Don't report an error so the execution can
1511 * continue normally.
1512 */
1513 ret = 0;
1514 DBG3("UST app disable channel failed. Application is dead.");
1515 }
1516 goto error;
1517 }
1518
1519 DBG2("UST app channel %s disabled successfully for app (pid: %d)",
1520 ua_chan->name, app->pid);
1521
1522 error:
1523 health_code_update();
1524 return ret;
1525 }
1526
1527 /*
1528 * Enable the specified channel on to UST tracer for the UST session.
1529 */
1530 static int enable_ust_channel(struct ust_app *app,
1531 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1532 {
1533 int ret;
1534
1535 health_code_update();
1536
1537 pthread_mutex_lock(&app->sock_lock);
1538 ret = ustctl_enable(app->sock, ua_chan->obj);
1539 pthread_mutex_unlock(&app->sock_lock);
1540 if (ret < 0) {
1541 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1542 ERR("UST app channel %s enable failed for app (pid: %d) "
1543 "and session handle %d with ret %d",
1544 ua_chan->name, app->pid, ua_sess->handle, ret);
1545 } else {
1546 /*
1547 * This is normal behavior, an application can die during the
1548 * creation process. Don't report an error so the execution can
1549 * continue normally.
1550 */
1551 ret = 0;
1552 DBG3("UST app enable channel failed. Application is dead.");
1553 }
1554 goto error;
1555 }
1556
1557 ua_chan->enabled = 1;
1558
1559 DBG2("UST app channel %s enabled successfully for app (pid: %d)",
1560 ua_chan->name, app->pid);
1561
1562 error:
1563 health_code_update();
1564 return ret;
1565 }
1566
1567 /*
1568 * Enable the specified event on to UST tracer for the UST session.
1569 */
1570 static int enable_ust_event(struct ust_app *app,
1571 struct ust_app_session *ua_sess, struct ust_app_event *ua_event)
1572 {
1573 int ret;
1574
1575 health_code_update();
1576
1577 pthread_mutex_lock(&app->sock_lock);
1578 ret = ustctl_enable(app->sock, ua_event->obj);
1579 pthread_mutex_unlock(&app->sock_lock);
1580 if (ret < 0) {
1581 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1582 ERR("UST app event %s enable failed for app (pid: %d) "
1583 "and session handle %d with ret %d",
1584 ua_event->attr.name, app->pid, ua_sess->handle, ret);
1585 } else {
1586 /*
1587 * This is normal behavior, an application can die during the
1588 * creation process. Don't report an error so the execution can
1589 * continue normally.
1590 */
1591 ret = 0;
1592 DBG3("UST app enable event failed. Application is dead.");
1593 }
1594 goto error;
1595 }
1596
1597 DBG2("UST app event %s enabled successfully for app (pid: %d)",
1598 ua_event->attr.name, app->pid);
1599
1600 error:
1601 health_code_update();
1602 return ret;
1603 }
1604
1605 /*
1606 * Send channel and stream buffer to application.
1607 *
1608 * Return 0 on success. On error, a negative value is returned.
1609 */
1610 static int send_channel_pid_to_ust(struct ust_app *app,
1611 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan)
1612 {
1613 int ret;
1614 struct ust_app_stream *stream, *stmp;
1615
1616 assert(app);
1617 assert(ua_sess);
1618 assert(ua_chan);
1619
1620 health_code_update();
1621
1622 DBG("UST app sending channel %s to UST app sock %d", ua_chan->name,
1623 app->sock);
1624
1625 /* Send channel to the application. */
1626 ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
1627 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
1628 ret = -ENOTCONN; /* Caused by app exiting. */
1629 goto error;
1630 } else if (ret < 0) {
1631 goto error;
1632 }
1633
1634 health_code_update();
1635
1636 /* Send all streams to application. */
1637 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
1638 ret = ust_consumer_send_stream_to_ust(app, ua_chan, stream);
1639 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
1640 ret = -ENOTCONN; /* Caused by app exiting. */
1641 goto error;
1642 } else if (ret < 0) {
1643 goto error;
1644 }
1645 /* We don't need the stream anymore once sent to the tracer. */
1646 cds_list_del(&stream->list);
1647 delete_ust_app_stream(-1, stream, app);
1648 }
1649 /* Flag the channel that it is sent to the application. */
1650 ua_chan->is_sent = 1;
1651
1652 error:
1653 health_code_update();
1654 return ret;
1655 }
1656
1657 /*
1658 * Create the specified event onto the UST tracer for a UST session.
1659 *
1660 * Should be called with session mutex held.
1661 */
1662 static
1663 int create_ust_event(struct ust_app *app, struct ust_app_session *ua_sess,
1664 struct ust_app_channel *ua_chan, struct ust_app_event *ua_event)
1665 {
1666 int ret = 0;
1667
1668 health_code_update();
1669
1670 /* Create UST event on tracer */
1671 pthread_mutex_lock(&app->sock_lock);
1672 ret = ustctl_create_event(app->sock, &ua_event->attr, ua_chan->obj,
1673 &ua_event->obj);
1674 pthread_mutex_unlock(&app->sock_lock);
1675 if (ret < 0) {
1676 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
1677 ERR("Error ustctl create event %s for app pid: %d with ret %d",
1678 ua_event->attr.name, app->pid, ret);
1679 } else {
1680 /*
1681 * This is normal behavior, an application can die during the
1682 * creation process. Don't report an error so the execution can
1683 * continue normally.
1684 */
1685 ret = 0;
1686 DBG3("UST app create event failed. Application is dead.");
1687 }
1688 goto error;
1689 }
1690
1691 ua_event->handle = ua_event->obj->handle;
1692
1693 DBG2("UST app event %s created successfully for pid:%d",
1694 ua_event->attr.name, app->pid);
1695
1696 health_code_update();
1697
1698 /* Set filter if one is present. */
1699 if (ua_event->filter) {
1700 ret = set_ust_event_filter(ua_event, app);
1701 if (ret < 0) {
1702 goto error;
1703 }
1704 }
1705
1706 /* Set exclusions for the event */
1707 if (ua_event->exclusion) {
1708 ret = set_ust_event_exclusion(ua_event, app);
1709 if (ret < 0) {
1710 goto error;
1711 }
1712 }
1713
1714 /* If event not enabled, disable it on the tracer */
1715 if (ua_event->enabled) {
1716 /*
1717 * We now need to explicitly enable the event, since it
1718 * is now disabled at creation.
1719 */
1720 ret = enable_ust_event(app, ua_sess, ua_event);
1721 if (ret < 0) {
1722 /*
1723 * If we hit an EPERM, something is wrong with our enable call. If
1724 * we get an EEXIST, there is a problem on the tracer side since we
1725 * just created it.
1726 */
1727 switch (ret) {
1728 case -LTTNG_UST_ERR_PERM:
1729 /* Code flow problem */
1730 assert(0);
1731 case -LTTNG_UST_ERR_EXIST:
1732 /* It's OK for our use case. */
1733 ret = 0;
1734 break;
1735 default:
1736 break;
1737 }
1738 goto error;
1739 }
1740 }
1741
1742 error:
1743 health_code_update();
1744 return ret;
1745 }
1746
1747 /*
1748 * Copy data between an UST app event and a LTT event.
1749 */
1750 static void shadow_copy_event(struct ust_app_event *ua_event,
1751 struct ltt_ust_event *uevent)
1752 {
1753 size_t exclusion_alloc_size;
1754
1755 strncpy(ua_event->name, uevent->attr.name, sizeof(ua_event->name));
1756 ua_event->name[sizeof(ua_event->name) - 1] = '\0';
1757
1758 ua_event->enabled = uevent->enabled;
1759
1760 /* Copy event attributes */
1761 memcpy(&ua_event->attr, &uevent->attr, sizeof(ua_event->attr));
1762
1763 /* Copy filter bytecode */
1764 if (uevent->filter) {
1765 ua_event->filter = copy_filter_bytecode(uevent->filter);
1766 /* Filter might be NULL here in case of ENONEM. */
1767 }
1768
1769 /* Copy exclusion data */
1770 if (uevent->exclusion) {
1771 exclusion_alloc_size = sizeof(struct lttng_event_exclusion) +
1772 LTTNG_UST_SYM_NAME_LEN * uevent->exclusion->count;
1773 ua_event->exclusion = zmalloc(exclusion_alloc_size);
1774 if (ua_event->exclusion == NULL) {
1775 PERROR("malloc");
1776 } else {
1777 memcpy(ua_event->exclusion, uevent->exclusion,
1778 exclusion_alloc_size);
1779 }
1780 }
1781 }
1782
1783 /*
1784 * Copy data between an UST app channel and a LTT channel.
1785 */
1786 static void shadow_copy_channel(struct ust_app_channel *ua_chan,
1787 struct ltt_ust_channel *uchan)
1788 {
1789 struct lttng_ht_iter iter;
1790 struct ltt_ust_event *uevent;
1791 struct ltt_ust_context *uctx;
1792 struct ust_app_event *ua_event;
1793
1794 DBG2("UST app shadow copy of channel %s started", ua_chan->name);
1795
1796 strncpy(ua_chan->name, uchan->name, sizeof(ua_chan->name));
1797 ua_chan->name[sizeof(ua_chan->name) - 1] = '\0';
1798
1799 ua_chan->tracefile_size = uchan->tracefile_size;
1800 ua_chan->tracefile_count = uchan->tracefile_count;
1801
1802 /* Copy event attributes since the layout is different. */
1803 ua_chan->attr.subbuf_size = uchan->attr.subbuf_size;
1804 ua_chan->attr.num_subbuf = uchan->attr.num_subbuf;
1805 ua_chan->attr.overwrite = uchan->attr.overwrite;
1806 ua_chan->attr.switch_timer_interval = uchan->attr.switch_timer_interval;
1807 ua_chan->attr.read_timer_interval = uchan->attr.read_timer_interval;
1808 ua_chan->attr.output = uchan->attr.output;
1809 /*
1810 * Note that the attribute channel type is not set since the channel on the
1811 * tracing registry side does not have this information.
1812 */
1813
1814 ua_chan->enabled = uchan->enabled;
1815 ua_chan->tracing_channel_id = uchan->id;
1816
1817 cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
1818 struct ust_app_ctx *ua_ctx = alloc_ust_app_ctx(&uctx->ctx);
1819
1820 if (ua_ctx == NULL) {
1821 continue;
1822 }
1823 lttng_ht_node_init_ulong(&ua_ctx->node,
1824 (unsigned long) ua_ctx->ctx.ctx);
1825 lttng_ht_add_ulong(ua_chan->ctx, &ua_ctx->node);
1826 cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list);
1827 }
1828
1829 /* Copy all events from ltt ust channel to ust app channel */
1830 cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
1831 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
1832 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
1833 if (ua_event == NULL) {
1834 DBG2("UST event %s not found on shadow copy channel",
1835 uevent->attr.name);
1836 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
1837 if (ua_event == NULL) {
1838 continue;
1839 }
1840 shadow_copy_event(ua_event, uevent);
1841 add_unique_ust_app_event(ua_chan, ua_event);
1842 }
1843 }
1844
1845 DBG3("UST app shadow copy of channel %s done", ua_chan->name);
1846 }
1847
1848 /*
1849 * Copy data between a UST app session and a regular LTT session.
1850 */
1851 static void shadow_copy_session(struct ust_app_session *ua_sess,
1852 struct ltt_ust_session *usess, struct ust_app *app)
1853 {
1854 struct lttng_ht_node_str *ua_chan_node;
1855 struct lttng_ht_iter iter;
1856 struct ltt_ust_channel *uchan;
1857 struct ust_app_channel *ua_chan;
1858 time_t rawtime;
1859 struct tm *timeinfo;
1860 char datetime[16];
1861 int ret;
1862 char tmp_shm_path[PATH_MAX];
1863
1864 /* Get date and time for unique app path */
1865 time(&rawtime);
1866 timeinfo = localtime(&rawtime);
1867 strftime(datetime, sizeof(datetime), "%Y%m%d-%H%M%S", timeinfo);
1868
1869 DBG2("Shadow copy of session handle %d", ua_sess->handle);
1870
1871 ua_sess->tracing_id = usess->id;
1872 ua_sess->id = get_next_session_id();
1873 ua_sess->uid = app->uid;
1874 ua_sess->gid = app->gid;
1875 ua_sess->euid = usess->uid;
1876 ua_sess->egid = usess->gid;
1877 ua_sess->buffer_type = usess->buffer_type;
1878 ua_sess->bits_per_long = app->bits_per_long;
1879
1880 /* There is only one consumer object per session possible. */
1881 consumer_output_get(usess->consumer);
1882 ua_sess->consumer = usess->consumer;
1883
1884 ua_sess->output_traces = usess->output_traces;
1885 ua_sess->live_timer_interval = usess->live_timer_interval;
1886 copy_channel_attr_to_ustctl(&ua_sess->metadata_attr,
1887 &usess->metadata_attr);
1888
1889 switch (ua_sess->buffer_type) {
1890 case LTTNG_BUFFER_PER_PID:
1891 ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
1892 DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s", app->name, app->pid,
1893 datetime);
1894 break;
1895 case LTTNG_BUFFER_PER_UID:
1896 ret = snprintf(ua_sess->path, sizeof(ua_sess->path),
1897 DEFAULT_UST_TRACE_UID_PATH, ua_sess->uid, app->bits_per_long);
1898 break;
1899 default:
1900 assert(0);
1901 goto error;
1902 }
1903 if (ret < 0) {
1904 PERROR("asprintf UST shadow copy session");
1905 assert(0);
1906 goto error;
1907 }
1908
1909 strncpy(ua_sess->root_shm_path, usess->root_shm_path,
1910 sizeof(ua_sess->root_shm_path));
1911 ua_sess->root_shm_path[sizeof(ua_sess->root_shm_path) - 1] = '\0';
1912 strncpy(ua_sess->shm_path, usess->shm_path,
1913 sizeof(ua_sess->shm_path));
1914 ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0';
1915 if (ua_sess->shm_path[0]) {
1916 switch (ua_sess->buffer_type) {
1917 case LTTNG_BUFFER_PER_PID:
1918 ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path),
1919 DEFAULT_UST_TRACE_PID_PATH "/%s-%d-%s",
1920 app->name, app->pid, datetime);
1921 break;
1922 case LTTNG_BUFFER_PER_UID:
1923 ret = snprintf(tmp_shm_path, sizeof(tmp_shm_path),
1924 DEFAULT_UST_TRACE_UID_PATH,
1925 app->uid, app->bits_per_long);
1926 break;
1927 default:
1928 assert(0);
1929 goto error;
1930 }
1931 if (ret < 0) {
1932 PERROR("sprintf UST shadow copy session");
1933 assert(0);
1934 goto error;
1935 }
1936 strncat(ua_sess->shm_path, tmp_shm_path,
1937 sizeof(ua_sess->shm_path) - strlen(ua_sess->shm_path) - 1);
1938 ua_sess->shm_path[sizeof(ua_sess->shm_path) - 1] = '\0';
1939 }
1940
1941 /* Iterate over all channels in global domain. */
1942 cds_lfht_for_each_entry(usess->domain_global.channels->ht, &iter.iter,
1943 uchan, node.node) {
1944 struct lttng_ht_iter uiter;
1945
1946 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
1947 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
1948 if (ua_chan_node != NULL) {
1949 /* Session exist. Contiuing. */
1950 continue;
1951 }
1952
1953 DBG2("Channel %s not found on shadow session copy, creating it",
1954 uchan->name);
1955 ua_chan = alloc_ust_app_channel(uchan->name, ua_sess,
1956 &uchan->attr);
1957 if (ua_chan == NULL) {
1958 /* malloc failed FIXME: Might want to do handle ENOMEM .. */
1959 continue;
1960 }
1961 shadow_copy_channel(ua_chan, uchan);
1962 /*
1963 * The concept of metadata channel does not exist on the tracing
1964 * registry side of the session daemon so this can only be a per CPU
1965 * channel and not metadata.
1966 */
1967 ua_chan->attr.type = LTTNG_UST_CHAN_PER_CPU;
1968
1969 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
1970 }
1971 return;
1972
1973 error:
1974 consumer_output_put(ua_sess->consumer);
1975 }
1976
1977 /*
1978 * Lookup sesison wrapper.
1979 */
1980 static
1981 void __lookup_session_by_app(struct ltt_ust_session *usess,
1982 struct ust_app *app, struct lttng_ht_iter *iter)
1983 {
1984 /* Get right UST app session from app */
1985 lttng_ht_lookup(app->sessions, &usess->id, iter);
1986 }
1987
1988 /*
1989 * Return ust app session from the app session hashtable using the UST session
1990 * id.
1991 */
1992 static struct ust_app_session *lookup_session_by_app(
1993 struct ltt_ust_session *usess, struct ust_app *app)
1994 {
1995 struct lttng_ht_iter iter;
1996 struct lttng_ht_node_u64 *node;
1997
1998 __lookup_session_by_app(usess, app, &iter);
1999 node = lttng_ht_iter_get_node_u64(&iter);
2000 if (node == NULL) {
2001 goto error;
2002 }
2003
2004 return caa_container_of(node, struct ust_app_session, node);
2005
2006 error:
2007 return NULL;
2008 }
2009
2010 /*
2011 * Setup buffer registry per PID for the given session and application. If none
2012 * is found, a new one is created, added to the global registry and
2013 * initialized. If regp is valid, it's set with the newly created object.
2014 *
2015 * Return 0 on success or else a negative value.
2016 */
2017 static int setup_buffer_reg_pid(struct ust_app_session *ua_sess,
2018 struct ust_app *app, struct buffer_reg_pid **regp)
2019 {
2020 int ret = 0;
2021 struct buffer_reg_pid *reg_pid;
2022
2023 assert(ua_sess);
2024 assert(app);
2025
2026 rcu_read_lock();
2027
2028 reg_pid = buffer_reg_pid_find(ua_sess->id);
2029 if (!reg_pid) {
2030 /*
2031 * This is the create channel path meaning that if there is NO
2032 * registry available, we have to create one for this session.
2033 */
2034 ret = buffer_reg_pid_create(ua_sess->id, &reg_pid,
2035 ua_sess->root_shm_path, ua_sess->shm_path);
2036 if (ret < 0) {
2037 goto error;
2038 }
2039 } else {
2040 goto end;
2041 }
2042
2043 /* Initialize registry. */
2044 ret = ust_registry_session_init(&reg_pid->registry->reg.ust, app,
2045 app->bits_per_long, app->uint8_t_alignment,
2046 app->uint16_t_alignment, app->uint32_t_alignment,
2047 app->uint64_t_alignment, app->long_alignment,
2048 app->byte_order, app->version.major,
2049 app->version.minor, reg_pid->root_shm_path,
2050 reg_pid->shm_path,
2051 ua_sess->euid, ua_sess->egid);
2052 if (ret < 0) {
2053 /*
2054 * reg_pid->registry->reg.ust is NULL upon error, so we need to
2055 * destroy the buffer registry, because it is always expected
2056 * that if the buffer registry can be found, its ust registry is
2057 * non-NULL.
2058 */
2059 buffer_reg_pid_destroy(reg_pid);
2060 goto error;
2061 }
2062
2063 buffer_reg_pid_add(reg_pid);
2064
2065 DBG3("UST app buffer registry per PID created successfully");
2066
2067 end:
2068 if (regp) {
2069 *regp = reg_pid;
2070 }
2071 error:
2072 rcu_read_unlock();
2073 return ret;
2074 }
2075
2076 /*
2077 * Setup buffer registry per UID for the given session and application. If none
2078 * is found, a new one is created, added to the global registry and
2079 * initialized. If regp is valid, it's set with the newly created object.
2080 *
2081 * Return 0 on success or else a negative value.
2082 */
2083 static int setup_buffer_reg_uid(struct ltt_ust_session *usess,
2084 struct ust_app_session *ua_sess,
2085 struct ust_app *app, struct buffer_reg_uid **regp)
2086 {
2087 int ret = 0;
2088 struct buffer_reg_uid *reg_uid;
2089
2090 assert(usess);
2091 assert(app);
2092
2093 rcu_read_lock();
2094
2095 reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
2096 if (!reg_uid) {
2097 /*
2098 * This is the create channel path meaning that if there is NO
2099 * registry available, we have to create one for this session.
2100 */
2101 ret = buffer_reg_uid_create(usess->id, app->bits_per_long, app->uid,
2102 LTTNG_DOMAIN_UST, &reg_uid,
2103 ua_sess->root_shm_path, ua_sess->shm_path);
2104 if (ret < 0) {
2105 goto error;
2106 }
2107 } else {
2108 goto end;
2109 }
2110
2111 /* Initialize registry. */
2112 ret = ust_registry_session_init(&reg_uid->registry->reg.ust, NULL,
2113 app->bits_per_long, app->uint8_t_alignment,
2114 app->uint16_t_alignment, app->uint32_t_alignment,
2115 app->uint64_t_alignment, app->long_alignment,
2116 app->byte_order, app->version.major,
2117 app->version.minor, reg_uid->root_shm_path,
2118 reg_uid->shm_path, usess->uid, usess->gid);
2119 if (ret < 0) {
2120 /*
2121 * reg_uid->registry->reg.ust is NULL upon error, so we need to
2122 * destroy the buffer registry, because it is always expected
2123 * that if the buffer registry can be found, its ust registry is
2124 * non-NULL.
2125 */
2126 buffer_reg_uid_destroy(reg_uid, NULL);
2127 goto error;
2128 }
2129 /* Add node to teardown list of the session. */
2130 cds_list_add(&reg_uid->lnode, &usess->buffer_reg_uid_list);
2131
2132 buffer_reg_uid_add(reg_uid);
2133
2134 DBG3("UST app buffer registry per UID created successfully");
2135 end:
2136 if (regp) {
2137 *regp = reg_uid;
2138 }
2139 error:
2140 rcu_read_unlock();
2141 return ret;
2142 }
2143
2144 /*
2145 * Create a session on the tracer side for the given app.
2146 *
2147 * On success, ua_sess_ptr is populated with the session pointer or else left
2148 * untouched. If the session was created, is_created is set to 1. On error,
2149 * it's left untouched. Note that ua_sess_ptr is mandatory but is_created can
2150 * be NULL.
2151 *
2152 * Returns 0 on success or else a negative code which is either -ENOMEM or
2153 * -ENOTCONN which is the default code if the ustctl_create_session fails.
2154 */
2155 static int create_ust_app_session(struct ltt_ust_session *usess,
2156 struct ust_app *app, struct ust_app_session **ua_sess_ptr,
2157 int *is_created)
2158 {
2159 int ret, created = 0;
2160 struct ust_app_session *ua_sess;
2161
2162 assert(usess);
2163 assert(app);
2164 assert(ua_sess_ptr);
2165
2166 health_code_update();
2167
2168 ua_sess = lookup_session_by_app(usess, app);
2169 if (ua_sess == NULL) {
2170 DBG2("UST app pid: %d session id %" PRIu64 " not found, creating it",
2171 app->pid, usess->id);
2172 ua_sess = alloc_ust_app_session(app);
2173 if (ua_sess == NULL) {
2174 /* Only malloc can failed so something is really wrong */
2175 ret = -ENOMEM;
2176 goto error;
2177 }
2178 shadow_copy_session(ua_sess, usess, app);
2179 created = 1;
2180 }
2181
2182 switch (usess->buffer_type) {
2183 case LTTNG_BUFFER_PER_PID:
2184 /* Init local registry. */
2185 ret = setup_buffer_reg_pid(ua_sess, app, NULL);
2186 if (ret < 0) {
2187 delete_ust_app_session(-1, ua_sess, app);
2188 goto error;
2189 }
2190 break;
2191 case LTTNG_BUFFER_PER_UID:
2192 /* Look for a global registry. If none exists, create one. */
2193 ret = setup_buffer_reg_uid(usess, ua_sess, app, NULL);
2194 if (ret < 0) {
2195 delete_ust_app_session(-1, ua_sess, app);
2196 goto error;
2197 }
2198 break;
2199 default:
2200 assert(0);
2201 ret = -EINVAL;
2202 goto error;
2203 }
2204
2205 health_code_update();
2206
2207 if (ua_sess->handle == -1) {
2208 pthread_mutex_lock(&app->sock_lock);
2209 ret = ustctl_create_session(app->sock);
2210 pthread_mutex_unlock(&app->sock_lock);
2211 if (ret < 0) {
2212 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
2213 ERR("Creating session for app pid %d with ret %d",
2214 app->pid, ret);
2215 } else {
2216 DBG("UST app creating session failed. Application is dead");
2217 /*
2218 * This is normal behavior, an application can die during the
2219 * creation process. Don't report an error so the execution can
2220 * continue normally. This will get flagged ENOTCONN and the
2221 * caller will handle it.
2222 */
2223 ret = 0;
2224 }
2225 delete_ust_app_session(-1, ua_sess, app);
2226 if (ret != -ENOMEM) {
2227 /*
2228 * Tracer is probably gone or got an internal error so let's
2229 * behave like it will soon unregister or not usable.
2230 */
2231 ret = -ENOTCONN;
2232 }
2233 goto error;
2234 }
2235
2236 ua_sess->handle = ret;
2237
2238 /* Add ust app session to app's HT */
2239 lttng_ht_node_init_u64(&ua_sess->node,
2240 ua_sess->tracing_id);
2241 lttng_ht_add_unique_u64(app->sessions, &ua_sess->node);
2242 lttng_ht_node_init_ulong(&ua_sess->ust_objd_node, ua_sess->handle);
2243 lttng_ht_add_unique_ulong(app->ust_sessions_objd,
2244 &ua_sess->ust_objd_node);
2245
2246 DBG2("UST app session created successfully with handle %d", ret);
2247 }
2248
2249 *ua_sess_ptr = ua_sess;
2250 if (is_created) {
2251 *is_created = created;
2252 }
2253
2254 /* Everything went well. */
2255 ret = 0;
2256
2257 error:
2258 health_code_update();
2259 return ret;
2260 }
2261
2262 /*
2263 * Match function for a hash table lookup of ust_app_ctx.
2264 *
2265 * It matches an ust app context based on the context type and, in the case
2266 * of perf counters, their name.
2267 */
2268 static int ht_match_ust_app_ctx(struct cds_lfht_node *node, const void *_key)
2269 {
2270 struct ust_app_ctx *ctx;
2271 const struct lttng_ust_context_attr *key;
2272
2273 assert(node);
2274 assert(_key);
2275
2276 ctx = caa_container_of(node, struct ust_app_ctx, node.node);
2277 key = _key;
2278
2279 /* Context type */
2280 if (ctx->ctx.ctx != key->ctx) {
2281 goto no_match;
2282 }
2283
2284 switch(key->ctx) {
2285 case LTTNG_UST_CONTEXT_PERF_THREAD_COUNTER:
2286 if (strncmp(key->u.perf_counter.name,
2287 ctx->ctx.u.perf_counter.name,
2288 sizeof(key->u.perf_counter.name))) {
2289 goto no_match;
2290 }
2291 break;
2292 case LTTNG_UST_CONTEXT_APP_CONTEXT:
2293 if (strcmp(key->u.app_ctx.provider_name,
2294 ctx->ctx.u.app_ctx.provider_name) ||
2295 strcmp(key->u.app_ctx.ctx_name,
2296 ctx->ctx.u.app_ctx.ctx_name)) {
2297 goto no_match;
2298 }
2299 break;
2300 default:
2301 break;
2302 }
2303
2304 /* Match. */
2305 return 1;
2306
2307 no_match:
2308 return 0;
2309 }
2310
2311 /*
2312 * Lookup for an ust app context from an lttng_ust_context.
2313 *
2314 * Must be called while holding RCU read side lock.
2315 * Return an ust_app_ctx object or NULL on error.
2316 */
2317 static
2318 struct ust_app_ctx *find_ust_app_context(struct lttng_ht *ht,
2319 struct lttng_ust_context_attr *uctx)
2320 {
2321 struct lttng_ht_iter iter;
2322 struct lttng_ht_node_ulong *node;
2323 struct ust_app_ctx *app_ctx = NULL;
2324
2325 assert(uctx);
2326 assert(ht);
2327
2328 /* Lookup using the lttng_ust_context_type and a custom match fct. */
2329 cds_lfht_lookup(ht->ht, ht->hash_fct((void *) uctx->ctx, lttng_ht_seed),
2330 ht_match_ust_app_ctx, uctx, &iter.iter);
2331 node = lttng_ht_iter_get_node_ulong(&iter);
2332 if (!node) {
2333 goto end;
2334 }
2335
2336 app_ctx = caa_container_of(node, struct ust_app_ctx, node);
2337
2338 end:
2339 return app_ctx;
2340 }
2341
2342 /*
2343 * Create a context for the channel on the tracer.
2344 *
2345 * Called with UST app session lock held and a RCU read side lock.
2346 */
2347 static
2348 int create_ust_app_channel_context(struct ust_app_session *ua_sess,
2349 struct ust_app_channel *ua_chan,
2350 struct lttng_ust_context_attr *uctx,
2351 struct ust_app *app)
2352 {
2353 int ret = 0;
2354 struct ust_app_ctx *ua_ctx;
2355
2356 DBG2("UST app adding context to channel %s", ua_chan->name);
2357
2358 ua_ctx = find_ust_app_context(ua_chan->ctx, uctx);
2359 if (ua_ctx) {
2360 ret = -EEXIST;
2361 goto error;
2362 }
2363
2364 ua_ctx = alloc_ust_app_ctx(uctx);
2365 if (ua_ctx == NULL) {
2366 /* malloc failed */
2367 ret = -1;
2368 goto error;
2369 }
2370
2371 lttng_ht_node_init_ulong(&ua_ctx->node, (unsigned long) ua_ctx->ctx.ctx);
2372 lttng_ht_add_ulong(ua_chan->ctx, &ua_ctx->node);
2373 cds_list_add_tail(&ua_ctx->list, &ua_chan->ctx_list);
2374
2375 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
2376 if (ret < 0) {
2377 goto error;
2378 }
2379
2380 error:
2381 return ret;
2382 }
2383
2384 /*
2385 * Enable on the tracer side a ust app event for the session and channel.
2386 *
2387 * Called with UST app session lock held.
2388 */
2389 static
2390 int enable_ust_app_event(struct ust_app_session *ua_sess,
2391 struct ust_app_event *ua_event, struct ust_app *app)
2392 {
2393 int ret;
2394
2395 ret = enable_ust_event(app, ua_sess, ua_event);
2396 if (ret < 0) {
2397 goto error;
2398 }
2399
2400 ua_event->enabled = 1;
2401
2402 error:
2403 return ret;
2404 }
2405
2406 /*
2407 * Disable on the tracer side a ust app event for the session and channel.
2408 */
2409 static int disable_ust_app_event(struct ust_app_session *ua_sess,
2410 struct ust_app_event *ua_event, struct ust_app *app)
2411 {
2412 int ret;
2413
2414 ret = disable_ust_event(app, ua_sess, ua_event);
2415 if (ret < 0) {
2416 goto error;
2417 }
2418
2419 ua_event->enabled = 0;
2420
2421 error:
2422 return ret;
2423 }
2424
2425 /*
2426 * Lookup ust app channel for session and disable it on the tracer side.
2427 */
2428 static
2429 int disable_ust_app_channel(struct ust_app_session *ua_sess,
2430 struct ust_app_channel *ua_chan, struct ust_app *app)
2431 {
2432 int ret;
2433
2434 ret = disable_ust_channel(app, ua_sess, ua_chan);
2435 if (ret < 0) {
2436 goto error;
2437 }
2438
2439 ua_chan->enabled = 0;
2440
2441 error:
2442 return ret;
2443 }
2444
2445 /*
2446 * Lookup ust app channel for session and enable it on the tracer side. This
2447 * MUST be called with a RCU read side lock acquired.
2448 */
2449 static int enable_ust_app_channel(struct ust_app_session *ua_sess,
2450 struct ltt_ust_channel *uchan, struct ust_app *app)
2451 {
2452 int ret = 0;
2453 struct lttng_ht_iter iter;
2454 struct lttng_ht_node_str *ua_chan_node;
2455 struct ust_app_channel *ua_chan;
2456
2457 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
2458 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
2459 if (ua_chan_node == NULL) {
2460 DBG2("Unable to find channel %s in ust session id %" PRIu64,
2461 uchan->name, ua_sess->tracing_id);
2462 goto error;
2463 }
2464
2465 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
2466
2467 ret = enable_ust_channel(app, ua_sess, ua_chan);
2468 if (ret < 0) {
2469 goto error;
2470 }
2471
2472 error:
2473 return ret;
2474 }
2475
2476 /*
2477 * Ask the consumer to create a channel and get it if successful.
2478 *
2479 * Return 0 on success or else a negative value.
2480 */
2481 static int do_consumer_create_channel(struct ltt_ust_session *usess,
2482 struct ust_app_session *ua_sess, struct ust_app_channel *ua_chan,
2483 int bitness, struct ust_registry_session *registry)
2484 {
2485 int ret;
2486 unsigned int nb_fd = 0;
2487 struct consumer_socket *socket;
2488
2489 assert(usess);
2490 assert(ua_sess);
2491 assert(ua_chan);
2492 assert(registry);
2493
2494 rcu_read_lock();
2495 health_code_update();
2496
2497 /* Get the right consumer socket for the application. */
2498 socket = consumer_find_socket_by_bitness(bitness, usess->consumer);
2499 if (!socket) {
2500 ret = -EINVAL;
2501 goto error;
2502 }
2503
2504 health_code_update();
2505
2506 /* Need one fd for the channel. */
2507 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2508 if (ret < 0) {
2509 ERR("Exhausted number of available FD upon create channel");
2510 goto error;
2511 }
2512
2513 /*
2514 * Ask consumer to create channel. The consumer will return the number of
2515 * stream we have to expect.
2516 */
2517 ret = ust_consumer_ask_channel(ua_sess, ua_chan, usess->consumer, socket,
2518 registry);
2519 if (ret < 0) {
2520 goto error_ask;
2521 }
2522
2523 /*
2524 * Compute the number of fd needed before receiving them. It must be 2 per
2525 * stream (2 being the default value here).
2526 */
2527 nb_fd = DEFAULT_UST_STREAM_FD_NUM * ua_chan->expected_stream_count;
2528
2529 /* Reserve the amount of file descriptor we need. */
2530 ret = lttng_fd_get(LTTNG_FD_APPS, nb_fd);
2531 if (ret < 0) {
2532 ERR("Exhausted number of available FD upon create channel");
2533 goto error_fd_get_stream;
2534 }
2535
2536 health_code_update();
2537
2538 /*
2539 * Now get the channel from the consumer. This call wil populate the stream
2540 * list of that channel and set the ust objects.
2541 */
2542 if (usess->consumer->enabled) {
2543 ret = ust_consumer_get_channel(socket, ua_chan);
2544 if (ret < 0) {
2545 goto error_destroy;
2546 }
2547 }
2548
2549 rcu_read_unlock();
2550 return 0;
2551
2552 error_destroy:
2553 lttng_fd_put(LTTNG_FD_APPS, nb_fd);
2554 error_fd_get_stream:
2555 /*
2556 * Initiate a destroy channel on the consumer since we had an error
2557 * handling it on our side. The return value is of no importance since we
2558 * already have a ret value set by the previous error that we need to
2559 * return.
2560 */
2561 (void) ust_consumer_destroy_channel(socket, ua_chan);
2562 error_ask:
2563 lttng_fd_put(LTTNG_FD_APPS, 1);
2564 error:
2565 health_code_update();
2566 rcu_read_unlock();
2567 return ret;
2568 }
2569
2570 /*
2571 * Duplicate the ust data object of the ust app stream and save it in the
2572 * buffer registry stream.
2573 *
2574 * Return 0 on success or else a negative value.
2575 */
2576 static int duplicate_stream_object(struct buffer_reg_stream *reg_stream,
2577 struct ust_app_stream *stream)
2578 {
2579 int ret;
2580
2581 assert(reg_stream);
2582 assert(stream);
2583
2584 /* Reserve the amount of file descriptor we need. */
2585 ret = lttng_fd_get(LTTNG_FD_APPS, 2);
2586 if (ret < 0) {
2587 ERR("Exhausted number of available FD upon duplicate stream");
2588 goto error;
2589 }
2590
2591 /* Duplicate object for stream once the original is in the registry. */
2592 ret = ustctl_duplicate_ust_object_data(&stream->obj,
2593 reg_stream->obj.ust);
2594 if (ret < 0) {
2595 ERR("Duplicate stream obj from %p to %p failed with ret %d",
2596 reg_stream->obj.ust, stream->obj, ret);
2597 lttng_fd_put(LTTNG_FD_APPS, 2);
2598 goto error;
2599 }
2600 stream->handle = stream->obj->handle;
2601
2602 error:
2603 return ret;
2604 }
2605
2606 /*
2607 * Duplicate the ust data object of the ust app. channel and save it in the
2608 * buffer registry channel.
2609 *
2610 * Return 0 on success or else a negative value.
2611 */
2612 static int duplicate_channel_object(struct buffer_reg_channel *reg_chan,
2613 struct ust_app_channel *ua_chan)
2614 {
2615 int ret;
2616
2617 assert(reg_chan);
2618 assert(ua_chan);
2619
2620 /* Need two fds for the channel. */
2621 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2622 if (ret < 0) {
2623 ERR("Exhausted number of available FD upon duplicate channel");
2624 goto error_fd_get;
2625 }
2626
2627 /* Duplicate object for stream once the original is in the registry. */
2628 ret = ustctl_duplicate_ust_object_data(&ua_chan->obj, reg_chan->obj.ust);
2629 if (ret < 0) {
2630 ERR("Duplicate channel obj from %p to %p failed with ret: %d",
2631 reg_chan->obj.ust, ua_chan->obj, ret);
2632 goto error;
2633 }
2634 ua_chan->handle = ua_chan->obj->handle;
2635
2636 return 0;
2637
2638 error:
2639 lttng_fd_put(LTTNG_FD_APPS, 1);
2640 error_fd_get:
2641 return ret;
2642 }
2643
2644 /*
2645 * For a given channel buffer registry, setup all streams of the given ust
2646 * application channel.
2647 *
2648 * Return 0 on success or else a negative value.
2649 */
2650 static int setup_buffer_reg_streams(struct buffer_reg_channel *reg_chan,
2651 struct ust_app_channel *ua_chan,
2652 struct ust_app *app)
2653 {
2654 int ret = 0;
2655 struct ust_app_stream *stream, *stmp;
2656
2657 assert(reg_chan);
2658 assert(ua_chan);
2659
2660 DBG2("UST app setup buffer registry stream");
2661
2662 /* Send all streams to application. */
2663 cds_list_for_each_entry_safe(stream, stmp, &ua_chan->streams.head, list) {
2664 struct buffer_reg_stream *reg_stream;
2665
2666 ret = buffer_reg_stream_create(&reg_stream);
2667 if (ret < 0) {
2668 goto error;
2669 }
2670
2671 /*
2672 * Keep original pointer and nullify it in the stream so the delete
2673 * stream call does not release the object.
2674 */
2675 reg_stream->obj.ust = stream->obj;
2676 stream->obj = NULL;
2677 buffer_reg_stream_add(reg_stream, reg_chan);
2678
2679 /* We don't need the streams anymore. */
2680 cds_list_del(&stream->list);
2681 delete_ust_app_stream(-1, stream, app);
2682 }
2683
2684 error:
2685 return ret;
2686 }
2687
2688 /*
2689 * Create a buffer registry channel for the given session registry and
2690 * application channel object. If regp pointer is valid, it's set with the
2691 * created object. Important, the created object is NOT added to the session
2692 * registry hash table.
2693 *
2694 * Return 0 on success else a negative value.
2695 */
2696 static int create_buffer_reg_channel(struct buffer_reg_session *reg_sess,
2697 struct ust_app_channel *ua_chan, struct buffer_reg_channel **regp)
2698 {
2699 int ret;
2700 struct buffer_reg_channel *reg_chan = NULL;
2701
2702 assert(reg_sess);
2703 assert(ua_chan);
2704
2705 DBG2("UST app creating buffer registry channel for %s", ua_chan->name);
2706
2707 /* Create buffer registry channel. */
2708 ret = buffer_reg_channel_create(ua_chan->tracing_channel_id, &reg_chan);
2709 if (ret < 0) {
2710 goto error_create;
2711 }
2712 assert(reg_chan);
2713 reg_chan->consumer_key = ua_chan->key;
2714 reg_chan->subbuf_size = ua_chan->attr.subbuf_size;
2715 reg_chan->num_subbuf = ua_chan->attr.num_subbuf;
2716
2717 /* Create and add a channel registry to session. */
2718 ret = ust_registry_channel_add(reg_sess->reg.ust,
2719 ua_chan->tracing_channel_id);
2720 if (ret < 0) {
2721 goto error;
2722 }
2723 buffer_reg_channel_add(reg_sess, reg_chan);
2724
2725 if (regp) {
2726 *regp = reg_chan;
2727 }
2728
2729 return 0;
2730
2731 error:
2732 /* Safe because the registry channel object was not added to any HT. */
2733 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2734 error_create:
2735 return ret;
2736 }
2737
2738 /*
2739 * Setup buffer registry channel for the given session registry and application
2740 * channel object. If regp pointer is valid, it's set with the created object.
2741 *
2742 * Return 0 on success else a negative value.
2743 */
2744 static int setup_buffer_reg_channel(struct buffer_reg_session *reg_sess,
2745 struct ust_app_channel *ua_chan, struct buffer_reg_channel *reg_chan,
2746 struct ust_app *app)
2747 {
2748 int ret;
2749
2750 assert(reg_sess);
2751 assert(reg_chan);
2752 assert(ua_chan);
2753 assert(ua_chan->obj);
2754
2755 DBG2("UST app setup buffer registry channel for %s", ua_chan->name);
2756
2757 /* Setup all streams for the registry. */
2758 ret = setup_buffer_reg_streams(reg_chan, ua_chan, app);
2759 if (ret < 0) {
2760 goto error;
2761 }
2762
2763 reg_chan->obj.ust = ua_chan->obj;
2764 ua_chan->obj = NULL;
2765
2766 return 0;
2767
2768 error:
2769 buffer_reg_channel_remove(reg_sess, reg_chan);
2770 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2771 return ret;
2772 }
2773
2774 /*
2775 * Send buffer registry channel to the application.
2776 *
2777 * Return 0 on success else a negative value.
2778 */
2779 static int send_channel_uid_to_ust(struct buffer_reg_channel *reg_chan,
2780 struct ust_app *app, struct ust_app_session *ua_sess,
2781 struct ust_app_channel *ua_chan)
2782 {
2783 int ret;
2784 struct buffer_reg_stream *reg_stream;
2785
2786 assert(reg_chan);
2787 assert(app);
2788 assert(ua_sess);
2789 assert(ua_chan);
2790
2791 DBG("UST app sending buffer registry channel to ust sock %d", app->sock);
2792
2793 ret = duplicate_channel_object(reg_chan, ua_chan);
2794 if (ret < 0) {
2795 goto error;
2796 }
2797
2798 /* Send channel to the application. */
2799 ret = ust_consumer_send_channel_to_ust(app, ua_sess, ua_chan);
2800 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
2801 ret = -ENOTCONN; /* Caused by app exiting. */
2802 goto error;
2803 } else if (ret < 0) {
2804 goto error;
2805 }
2806
2807 health_code_update();
2808
2809 /* Send all streams to application. */
2810 pthread_mutex_lock(&reg_chan->stream_list_lock);
2811 cds_list_for_each_entry(reg_stream, &reg_chan->streams, lnode) {
2812 struct ust_app_stream stream;
2813
2814 ret = duplicate_stream_object(reg_stream, &stream);
2815 if (ret < 0) {
2816 goto error_stream_unlock;
2817 }
2818
2819 ret = ust_consumer_send_stream_to_ust(app, ua_chan, &stream);
2820 if (ret < 0) {
2821 (void) release_ust_app_stream(-1, &stream, app);
2822 if (ret == -EPIPE || ret == -LTTNG_UST_ERR_EXITING) {
2823 ret = -ENOTCONN; /* Caused by app exiting. */
2824 }
2825 goto error_stream_unlock;
2826 }
2827
2828 /*
2829 * The return value is not important here. This function will output an
2830 * error if needed.
2831 */
2832 (void) release_ust_app_stream(-1, &stream, app);
2833 }
2834 ua_chan->is_sent = 1;
2835
2836 error_stream_unlock:
2837 pthread_mutex_unlock(&reg_chan->stream_list_lock);
2838 error:
2839 return ret;
2840 }
2841
2842 /*
2843 * Create and send to the application the created buffers with per UID buffers.
2844 *
2845 * Return 0 on success else a negative value.
2846 */
2847 static int create_channel_per_uid(struct ust_app *app,
2848 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2849 struct ust_app_channel *ua_chan)
2850 {
2851 int ret;
2852 struct buffer_reg_uid *reg_uid;
2853 struct buffer_reg_channel *reg_chan;
2854
2855 assert(app);
2856 assert(usess);
2857 assert(ua_sess);
2858 assert(ua_chan);
2859
2860 DBG("UST app creating channel %s with per UID buffers", ua_chan->name);
2861
2862 reg_uid = buffer_reg_uid_find(usess->id, app->bits_per_long, app->uid);
2863 /*
2864 * The session creation handles the creation of this global registry
2865 * object. If none can be find, there is a code flow problem or a
2866 * teardown race.
2867 */
2868 assert(reg_uid);
2869
2870 reg_chan = buffer_reg_channel_find(ua_chan->tracing_channel_id,
2871 reg_uid);
2872 if (!reg_chan) {
2873 /* Create the buffer registry channel object. */
2874 ret = create_buffer_reg_channel(reg_uid->registry, ua_chan, &reg_chan);
2875 if (ret < 0) {
2876 ERR("Error creating the UST channel \"%s\" registry instance",
2877 ua_chan->name);
2878 goto error;
2879 }
2880 assert(reg_chan);
2881
2882 /*
2883 * Create the buffers on the consumer side. This call populates the
2884 * ust app channel object with all streams and data object.
2885 */
2886 ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
2887 app->bits_per_long, reg_uid->registry->reg.ust);
2888 if (ret < 0) {
2889 ERR("Error creating UST channel \"%s\" on the consumer daemon",
2890 ua_chan->name);
2891
2892 /*
2893 * Let's remove the previously created buffer registry channel so
2894 * it's not visible anymore in the session registry.
2895 */
2896 ust_registry_channel_del_free(reg_uid->registry->reg.ust,
2897 ua_chan->tracing_channel_id);
2898 buffer_reg_channel_remove(reg_uid->registry, reg_chan);
2899 buffer_reg_channel_destroy(reg_chan, LTTNG_DOMAIN_UST);
2900 goto error;
2901 }
2902
2903 /*
2904 * Setup the streams and add it to the session registry.
2905 */
2906 ret = setup_buffer_reg_channel(reg_uid->registry,
2907 ua_chan, reg_chan, app);
2908 if (ret < 0) {
2909 ERR("Error setting up UST channel \"%s\"",
2910 ua_chan->name);
2911 goto error;
2912 }
2913
2914 }
2915
2916 /* Send buffers to the application. */
2917 ret = send_channel_uid_to_ust(reg_chan, app, ua_sess, ua_chan);
2918 if (ret < 0) {
2919 if (ret != -ENOTCONN) {
2920 ERR("Error sending channel to application");
2921 }
2922 goto error;
2923 }
2924
2925 error:
2926 return ret;
2927 }
2928
2929 /*
2930 * Create and send to the application the created buffers with per PID buffers.
2931 *
2932 * Return 0 on success else a negative value.
2933 */
2934 static int create_channel_per_pid(struct ust_app *app,
2935 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2936 struct ust_app_channel *ua_chan)
2937 {
2938 int ret;
2939 struct ust_registry_session *registry;
2940
2941 assert(app);
2942 assert(usess);
2943 assert(ua_sess);
2944 assert(ua_chan);
2945
2946 DBG("UST app creating channel %s with per PID buffers", ua_chan->name);
2947
2948 rcu_read_lock();
2949
2950 registry = get_session_registry(ua_sess);
2951 assert(registry);
2952
2953 /* Create and add a new channel registry to session. */
2954 ret = ust_registry_channel_add(registry, ua_chan->key);
2955 if (ret < 0) {
2956 ERR("Error creating the UST channel \"%s\" registry instance",
2957 ua_chan->name);
2958 goto error;
2959 }
2960
2961 /* Create and get channel on the consumer side. */
2962 ret = do_consumer_create_channel(usess, ua_sess, ua_chan,
2963 app->bits_per_long, registry);
2964 if (ret < 0) {
2965 ERR("Error creating UST channel \"%s\" on the consumer daemon",
2966 ua_chan->name);
2967 goto error;
2968 }
2969
2970 ret = send_channel_pid_to_ust(app, ua_sess, ua_chan);
2971 if (ret < 0) {
2972 if (ret != -ENOTCONN) {
2973 ERR("Error sending channel to application");
2974 }
2975 goto error;
2976 }
2977
2978 error:
2979 rcu_read_unlock();
2980 return ret;
2981 }
2982
2983 /*
2984 * From an already allocated ust app channel, create the channel buffers if
2985 * need and send it to the application. This MUST be called with a RCU read
2986 * side lock acquired.
2987 *
2988 * Return 0 on success or else a negative value. Returns -ENOTCONN if
2989 * the application exited concurrently.
2990 */
2991 static int do_create_channel(struct ust_app *app,
2992 struct ltt_ust_session *usess, struct ust_app_session *ua_sess,
2993 struct ust_app_channel *ua_chan)
2994 {
2995 int ret;
2996
2997 assert(app);
2998 assert(usess);
2999 assert(ua_sess);
3000 assert(ua_chan);
3001
3002 /* Handle buffer type before sending the channel to the application. */
3003 switch (usess->buffer_type) {
3004 case LTTNG_BUFFER_PER_UID:
3005 {
3006 ret = create_channel_per_uid(app, usess, ua_sess, ua_chan);
3007 if (ret < 0) {
3008 goto error;
3009 }
3010 break;
3011 }
3012 case LTTNG_BUFFER_PER_PID:
3013 {
3014 ret = create_channel_per_pid(app, usess, ua_sess, ua_chan);
3015 if (ret < 0) {
3016 goto error;
3017 }
3018 break;
3019 }
3020 default:
3021 assert(0);
3022 ret = -EINVAL;
3023 goto error;
3024 }
3025
3026 /* Initialize ust objd object using the received handle and add it. */
3027 lttng_ht_node_init_ulong(&ua_chan->ust_objd_node, ua_chan->handle);
3028 lttng_ht_add_unique_ulong(app->ust_objd, &ua_chan->ust_objd_node);
3029
3030 /* If channel is not enabled, disable it on the tracer */
3031 if (!ua_chan->enabled) {
3032 ret = disable_ust_channel(app, ua_sess, ua_chan);
3033 if (ret < 0) {
3034 goto error;
3035 }
3036 }
3037
3038 error:
3039 return ret;
3040 }
3041
3042 /*
3043 * Create UST app channel and create it on the tracer. Set ua_chanp of the
3044 * newly created channel if not NULL.
3045 *
3046 * Called with UST app session lock and RCU read-side lock held.
3047 *
3048 * Return 0 on success or else a negative value. Returns -ENOTCONN if
3049 * the application exited concurrently.
3050 */
3051 static int create_ust_app_channel(struct ust_app_session *ua_sess,
3052 struct ltt_ust_channel *uchan, struct ust_app *app,
3053 enum lttng_ust_chan_type type, struct ltt_ust_session *usess,
3054 struct ust_app_channel **ua_chanp)
3055 {
3056 int ret = 0;
3057 struct lttng_ht_iter iter;
3058 struct lttng_ht_node_str *ua_chan_node;
3059 struct ust_app_channel *ua_chan;
3060
3061 /* Lookup channel in the ust app session */
3062 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
3063 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
3064 if (ua_chan_node != NULL) {
3065 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
3066 goto end;
3067 }
3068
3069 ua_chan = alloc_ust_app_channel(uchan->name, ua_sess, &uchan->attr);
3070 if (ua_chan == NULL) {
3071 /* Only malloc can fail here */
3072 ret = -ENOMEM;
3073 goto error_alloc;
3074 }
3075 shadow_copy_channel(ua_chan, uchan);
3076
3077 /* Set channel type. */
3078 ua_chan->attr.type = type;
3079
3080 ret = do_create_channel(app, usess, ua_sess, ua_chan);
3081 if (ret < 0) {
3082 goto error;
3083 }
3084
3085 DBG2("UST app create channel %s for PID %d completed", ua_chan->name,
3086 app->pid);
3087
3088 /* Only add the channel if successful on the tracer side. */
3089 lttng_ht_add_unique_str(ua_sess->channels, &ua_chan->node);
3090
3091 end:
3092 if (ua_chanp) {
3093 *ua_chanp = ua_chan;
3094 }
3095
3096 /* Everything went well. */
3097 return 0;
3098
3099 error:
3100 delete_ust_app_channel(ua_chan->is_sent ? app->sock : -1, ua_chan, app);
3101 error_alloc:
3102 return ret;
3103 }
3104
3105 /*
3106 * Create UST app event and create it on the tracer side.
3107 *
3108 * Called with ust app session mutex held.
3109 */
3110 static
3111 int create_ust_app_event(struct ust_app_session *ua_sess,
3112 struct ust_app_channel *ua_chan, struct ltt_ust_event *uevent,
3113 struct ust_app *app)
3114 {
3115 int ret = 0;
3116 struct ust_app_event *ua_event;
3117
3118 /* Get event node */
3119 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
3120 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
3121 if (ua_event != NULL) {
3122 ret = -EEXIST;
3123 goto end;
3124 }
3125
3126 /* Does not exist so create one */
3127 ua_event = alloc_ust_app_event(uevent->attr.name, &uevent->attr);
3128 if (ua_event == NULL) {
3129 /* Only malloc can failed so something is really wrong */
3130 ret = -ENOMEM;
3131 goto end;
3132 }
3133 shadow_copy_event(ua_event, uevent);
3134
3135 /* Create it on the tracer side */
3136 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
3137 if (ret < 0) {
3138 /* Not found previously means that it does not exist on the tracer */
3139 assert(ret != -LTTNG_UST_ERR_EXIST);
3140 goto error;
3141 }
3142
3143 add_unique_ust_app_event(ua_chan, ua_event);
3144
3145 DBG2("UST app create event %s for PID %d completed", ua_event->name,
3146 app->pid);
3147
3148 end:
3149 return ret;
3150
3151 error:
3152 /* Valid. Calling here is already in a read side lock */
3153 delete_ust_app_event(-1, ua_event, app);
3154 return ret;
3155 }
3156
3157 /*
3158 * Create UST metadata and open it on the tracer side.
3159 *
3160 * Called with UST app session lock held and RCU read side lock.
3161 */
3162 static int create_ust_app_metadata(struct ust_app_session *ua_sess,
3163 struct ust_app *app, struct consumer_output *consumer)
3164 {
3165 int ret = 0;
3166 struct ust_app_channel *metadata;
3167 struct consumer_socket *socket;
3168 struct ust_registry_session *registry;
3169
3170 assert(ua_sess);
3171 assert(app);
3172 assert(consumer);
3173
3174 registry = get_session_registry(ua_sess);
3175 assert(registry);
3176
3177 pthread_mutex_lock(&registry->lock);
3178
3179 /* Metadata already exists for this registry or it was closed previously */
3180 if (registry->metadata_key || registry->metadata_closed) {
3181 ret = 0;
3182 goto error;
3183 }
3184
3185 /* Allocate UST metadata */
3186 metadata = alloc_ust_app_channel(DEFAULT_METADATA_NAME, ua_sess, NULL);
3187 if (!metadata) {
3188 /* malloc() failed */
3189 ret = -ENOMEM;
3190 goto error;
3191 }
3192
3193 memcpy(&metadata->attr, &ua_sess->metadata_attr, sizeof(metadata->attr));
3194
3195 /* Need one fd for the channel. */
3196 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
3197 if (ret < 0) {
3198 ERR("Exhausted number of available FD upon create metadata");
3199 goto error;
3200 }
3201
3202 /* Get the right consumer socket for the application. */
3203 socket = consumer_find_socket_by_bitness(app->bits_per_long, consumer);
3204 if (!socket) {
3205 ret = -EINVAL;
3206 goto error_consumer;
3207 }
3208
3209 /*
3210 * Keep metadata key so we can identify it on the consumer side. Assign it
3211 * to the registry *before* we ask the consumer so we avoid the race of the
3212 * consumer requesting the metadata and the ask_channel call on our side
3213 * did not returned yet.
3214 */
3215 registry->metadata_key = metadata->key;
3216
3217 /*
3218 * Ask the metadata channel creation to the consumer. The metadata object
3219 * will be created by the consumer and kept their. However, the stream is
3220 * never added or monitored until we do a first push metadata to the
3221 * consumer.
3222 */
3223 ret = ust_consumer_ask_channel(ua_sess, metadata, consumer, socket,
3224 registry);
3225 if (ret < 0) {
3226 /* Nullify the metadata key so we don't try to close it later on. */
3227 registry->metadata_key = 0;
3228 goto error_consumer;
3229 }
3230
3231 /*
3232 * The setup command will make the metadata stream be sent to the relayd,
3233 * if applicable, and the thread managing the metadatas. This is important
3234 * because after this point, if an error occurs, the only way the stream
3235 * can be deleted is to be monitored in the consumer.
3236 */
3237 ret = consumer_setup_metadata(socket, metadata->key);
3238 if (ret < 0) {
3239 /* Nullify the metadata key so we don't try to close it later on. */
3240 registry->metadata_key = 0;
3241 goto error_consumer;
3242 }
3243
3244 DBG2("UST metadata with key %" PRIu64 " created for app pid %d",
3245 metadata->key, app->pid);
3246
3247 error_consumer:
3248 lttng_fd_put(LTTNG_FD_APPS, 1);
3249 delete_ust_app_channel(-1, metadata, app);
3250 error:
3251 pthread_mutex_unlock(&registry->lock);
3252 return ret;
3253 }
3254
3255 /*
3256 * Return ust app pointer or NULL if not found. RCU read side lock MUST be
3257 * acquired before calling this function.
3258 */
3259 struct ust_app *ust_app_find_by_pid(pid_t pid)
3260 {
3261 struct ust_app *app = NULL;
3262 struct lttng_ht_node_ulong *node;
3263 struct lttng_ht_iter iter;
3264
3265 lttng_ht_lookup(ust_app_ht, (void *)((unsigned long) pid), &iter);
3266 node = lttng_ht_iter_get_node_ulong(&iter);
3267 if (node == NULL) {
3268 DBG2("UST app no found with pid %d", pid);
3269 goto error;
3270 }
3271
3272 DBG2("Found UST app by pid %d", pid);
3273
3274 app = caa_container_of(node, struct ust_app, pid_n);
3275
3276 error:
3277 return app;
3278 }
3279
3280 /*
3281 * Allocate and init an UST app object using the registration information and
3282 * the command socket. This is called when the command socket connects to the
3283 * session daemon.
3284 *
3285 * The object is returned on success or else NULL.
3286 */
3287 struct ust_app *ust_app_create(struct ust_register_msg *msg, int sock)
3288 {
3289 struct ust_app *lta = NULL;
3290
3291 assert(msg);
3292 assert(sock >= 0);
3293
3294 DBG3("UST app creating application for socket %d", sock);
3295
3296 if ((msg->bits_per_long == 64 &&
3297 (uatomic_read(&ust_consumerd64_fd) == -EINVAL))
3298 || (msg->bits_per_long == 32 &&
3299 (uatomic_read(&ust_consumerd32_fd) == -EINVAL))) {
3300 ERR("Registration failed: application \"%s\" (pid: %d) has "
3301 "%d-bit long, but no consumerd for this size is available.\n",
3302 msg->name, msg->pid, msg->bits_per_long);
3303 goto error;
3304 }
3305
3306 lta = zmalloc(sizeof(struct ust_app));
3307 if (lta == NULL) {
3308 PERROR("malloc");
3309 goto error;
3310 }
3311
3312 lta->ppid = msg->ppid;
3313 lta->uid = msg->uid;
3314 lta->gid = msg->gid;
3315
3316 lta->bits_per_long = msg->bits_per_long;
3317 lta->uint8_t_alignment = msg->uint8_t_alignment;
3318 lta->uint16_t_alignment = msg->uint16_t_alignment;
3319 lta->uint32_t_alignment = msg->uint32_t_alignment;
3320 lta->uint64_t_alignment = msg->uint64_t_alignment;
3321 lta->long_alignment = msg->long_alignment;
3322 lta->byte_order = msg->byte_order;
3323
3324 lta->v_major = msg->major;
3325 lta->v_minor = msg->minor;
3326 lta->sessions = lttng_ht_new(0, LTTNG_HT_TYPE_U64);
3327 lta->ust_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
3328 lta->ust_sessions_objd = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
3329 lta->notify_sock = -1;
3330
3331 /* Copy name and make sure it's NULL terminated. */
3332 strncpy(lta->name, msg->name, sizeof(lta->name));
3333 lta->name[UST_APP_PROCNAME_LEN] = '\0';
3334
3335 /*
3336 * Before this can be called, when receiving the registration information,
3337 * the application compatibility is checked. So, at this point, the
3338 * application can work with this session daemon.
3339 */
3340 lta->compatible = 1;
3341
3342 lta->pid = msg->pid;
3343 lttng_ht_node_init_ulong(&lta->pid_n, (unsigned long) lta->pid);
3344 lta->sock = sock;
3345 pthread_mutex_init(&lta->sock_lock, NULL);
3346 lttng_ht_node_init_ulong(&lta->sock_n, (unsigned long) lta->sock);
3347
3348 CDS_INIT_LIST_HEAD(&lta->teardown_head);
3349 error:
3350 return lta;
3351 }
3352
3353 /*
3354 * For a given application object, add it to every hash table.
3355 */
3356 void ust_app_add(struct ust_app *app)
3357 {
3358 assert(app);
3359 assert(app->notify_sock >= 0);
3360
3361 rcu_read_lock();
3362
3363 /*
3364 * On a re-registration, we want to kick out the previous registration of
3365 * that pid
3366 */
3367 lttng_ht_add_replace_ulong(ust_app_ht, &app->pid_n);
3368
3369 /*
3370 * The socket _should_ be unique until _we_ call close. So, a add_unique
3371 * for the ust_app_ht_by_sock is used which asserts fail if the entry was
3372 * already in the table.
3373 */
3374 lttng_ht_add_unique_ulong(ust_app_ht_by_sock, &app->sock_n);
3375
3376 /* Add application to the notify socket hash table. */
3377 lttng_ht_node_init_ulong(&app->notify_sock_n, app->notify_sock);
3378 lttng_ht_add_unique_ulong(ust_app_ht_by_notify_sock, &app->notify_sock_n);
3379
3380 DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s "
3381 "notify_sock:%d (version %d.%d)", app->pid, app->ppid, app->uid,
3382 app->gid, app->sock, app->name, app->notify_sock, app->v_major,
3383 app->v_minor);
3384
3385 rcu_read_unlock();
3386 }
3387
3388 /*
3389 * Set the application version into the object.
3390 *
3391 * Return 0 on success else a negative value either an errno code or a
3392 * LTTng-UST error code.
3393 */
3394 int ust_app_version(struct ust_app *app)
3395 {
3396 int ret;
3397
3398 assert(app);
3399
3400 pthread_mutex_lock(&app->sock_lock);
3401 ret = ustctl_tracer_version(app->sock, &app->version);
3402 pthread_mutex_unlock(&app->sock_lock);
3403 if (ret < 0) {
3404 if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
3405 ERR("UST app %d version failed with ret %d", app->sock, ret);
3406 } else {
3407 DBG3("UST app %d version failed. Application is dead", app->sock);
3408 }
3409 }
3410
3411 return ret;
3412 }
3413
3414 /*
3415 * Unregister app by removing it from the global traceable app list and freeing
3416 * the data struct.
3417 *
3418 * The socket is already closed at this point so no close to sock.
3419 */
3420 void ust_app_unregister(int sock)
3421 {
3422 struct ust_app *lta;
3423 struct lttng_ht_node_ulong *node;
3424 struct lttng_ht_iter ust_app_sock_iter;
3425 struct lttng_ht_iter iter;
3426 struct ust_app_session *ua_sess;
3427 int ret;
3428
3429 rcu_read_lock();
3430
3431 /* Get the node reference for a call_rcu */
3432 lttng_ht_lookup(ust_app_ht_by_sock, (void *)((unsigned long) sock), &ust_app_sock_iter);
3433 node = lttng_ht_iter_get_node_ulong(&ust_app_sock_iter);
3434 assert(node);
3435
3436 lta = caa_container_of(node, struct ust_app, sock_n);
3437 DBG("PID %d unregistering with sock %d", lta->pid, sock);
3438
3439 /*
3440 * For per-PID buffers, perform "push metadata" and flush all
3441 * application streams before removing app from hash tables,
3442 * ensuring proper behavior of data_pending check.
3443 * Remove sessions so they are not visible during deletion.
3444 */
3445 cds_lfht_for_each_entry(lta->sessions->ht, &iter.iter, ua_sess,
3446 node.node) {
3447 struct ust_registry_session *registry;
3448
3449 ret = lttng_ht_del(lta->sessions, &iter);
3450 if (ret) {
3451 /* The session was already removed so scheduled for teardown. */
3452 continue;
3453 }
3454
3455 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_PID) {
3456 (void) ust_app_flush_app_session(lta, ua_sess);
3457 }
3458
3459 /*
3460 * Add session to list for teardown. This is safe since at this point we
3461 * are the only one using this list.
3462 */
3463 pthread_mutex_lock(&ua_sess->lock);
3464
3465 if (ua_sess->deleted) {
3466 pthread_mutex_unlock(&ua_sess->lock);
3467 continue;
3468 }
3469
3470 /*
3471 * Normally, this is done in the delete session process which is
3472 * executed in the call rcu below. However, upon registration we can't
3473 * afford to wait for the grace period before pushing data or else the
3474 * data pending feature can race between the unregistration and stop
3475 * command where the data pending command is sent *before* the grace
3476 * period ended.
3477 *
3478 * The close metadata below nullifies the metadata pointer in the
3479 * session so the delete session will NOT push/close a second time.
3480 */
3481 registry = get_session_registry(ua_sess);
3482 if (registry) {
3483 /* Push metadata for application before freeing the application. */
3484 (void) push_metadata(registry, ua_sess->consumer);
3485
3486 /*
3487 * Don't ask to close metadata for global per UID buffers. Close
3488 * metadata only on destroy trace session in this case. Also, the
3489 * previous push metadata could have flag the metadata registry to
3490 * close so don't send a close command if closed.
3491 */
3492 if (ua_sess->buffer_type != LTTNG_BUFFER_PER_UID) {
3493 /* And ask to close it for this session registry. */
3494 (void) close_metadata(registry, ua_sess->consumer);
3495 }
3496 }
3497 cds_list_add(&ua_sess->teardown_node, &lta->teardown_head);
3498
3499 pthread_mutex_unlock(&ua_sess->lock);
3500 }
3501
3502 /* Remove application from PID hash table */
3503 ret = lttng_ht_del(ust_app_ht_by_sock, &ust_app_sock_iter);
3504 assert(!ret);
3505
3506 /*
3507 * Remove application from notify hash table. The thread handling the
3508 * notify socket could have deleted the node so ignore on error because
3509 * either way it's valid. The close of that socket is handled by the other
3510 * thread.
3511 */
3512 iter.iter.node = &lta->notify_sock_n.node;
3513 (void) lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
3514
3515 /*
3516 * Ignore return value since the node might have been removed before by an
3517 * add replace during app registration because the PID can be reassigned by
3518 * the OS.
3519 */
3520 iter.iter.node = &lta->pid_n.node;
3521 ret = lttng_ht_del(ust_app_ht, &iter);
3522 if (ret) {
3523 DBG3("Unregister app by PID %d failed. This can happen on pid reuse",
3524 lta->pid);
3525 }
3526
3527 /* Free memory */
3528 call_rcu(&lta->pid_n.head, delete_ust_app_rcu);
3529
3530 rcu_read_unlock();
3531 return;
3532 }
3533
3534 /*
3535 * Fill events array with all events name of all registered apps.
3536 */
3537 int ust_app_list_events(struct lttng_event **events)
3538 {
3539 int ret, handle;
3540 size_t nbmem, count = 0;
3541 struct lttng_ht_iter iter;
3542 struct ust_app *app;
3543 struct lttng_event *tmp_event;
3544
3545 nbmem = UST_APP_EVENT_LIST_SIZE;
3546 tmp_event = zmalloc(nbmem * sizeof(struct lttng_event));
3547 if (tmp_event == NULL) {
3548 PERROR("zmalloc ust app events");
3549 ret = -ENOMEM;
3550 goto error;
3551 }
3552
3553 rcu_read_lock();
3554
3555 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
3556 struct lttng_ust_tracepoint_iter uiter;
3557
3558 health_code_update();
3559
3560 if (!app->compatible) {
3561 /*
3562 * TODO: In time, we should notice the caller of this error by
3563 * telling him that this is a version error.
3564 */
3565 continue;
3566 }
3567 pthread_mutex_lock(&app->sock_lock);
3568 handle = ustctl_tracepoint_list(app->sock);
3569 if (handle < 0) {
3570 if (handle != -EPIPE && handle != -LTTNG_UST_ERR_EXITING) {
3571 ERR("UST app list events getting handle failed for app pid %d",
3572 app->pid);
3573 }
3574 pthread_mutex_unlock(&app->sock_lock);
3575 continue;
3576 }
3577
3578 while ((ret = ustctl_tracepoint_list_get(app->sock, handle,
3579 &uiter)) != -LTTNG_UST_ERR_NOENT) {
3580 /* Handle ustctl error. */
3581 if (ret < 0) {
3582 int release_ret;
3583
3584 if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
3585 ERR("UST app tp list get failed for app %d with ret %d",
3586 app->sock, ret);
3587 } else {
3588 DBG3("UST app tp list get failed. Application is dead");
3589 /*
3590 * This is normal behavior, an application can die during the
3591 * creation process. Don't report an error so the execution can
3592 * continue normally. Continue normal execution.
3593 */
3594 break;
3595 }
3596 free(tmp_event);
3597 release_ret = ustctl_release_handle(app->sock, handle);
3598 if (release_ret < 0 &&
3599 release_ret != -LTTNG_UST_ERR_EXITING &&
3600 release_ret != -EPIPE) {
3601 ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret);
3602 }
3603 pthread_mutex_unlock(&app->sock_lock);
3604 goto rcu_error;
3605 }
3606
3607 health_code_update();
3608 if (count >= nbmem) {
3609 /* In case the realloc fails, we free the memory */
3610 struct lttng_event *new_tmp_event;
3611 size_t new_nbmem;
3612
3613 new_nbmem = nbmem << 1;
3614 DBG2("Reallocating event list from %zu to %zu entries",
3615 nbmem, new_nbmem);
3616 new_tmp_event = realloc(tmp_event,
3617 new_nbmem * sizeof(struct lttng_event));
3618 if (new_tmp_event == NULL) {
3619 int release_ret;
3620
3621 PERROR("realloc ust app events");
3622 free(tmp_event);
3623 ret = -ENOMEM;
3624 release_ret = ustctl_release_handle(app->sock, handle);
3625 if (release_ret < 0 &&
3626 release_ret != -LTTNG_UST_ERR_EXITING &&
3627 release_ret != -EPIPE) {
3628 ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret);
3629 }
3630 pthread_mutex_unlock(&app->sock_lock);
3631 goto rcu_error;
3632 }
3633 /* Zero the new memory */
3634 memset(new_tmp_event + nbmem, 0,
3635 (new_nbmem - nbmem) * sizeof(struct lttng_event));
3636 nbmem = new_nbmem;
3637 tmp_event = new_tmp_event;
3638 }
3639 memcpy(tmp_event[count].name, uiter.name, LTTNG_UST_SYM_NAME_LEN);
3640 tmp_event[count].loglevel = uiter.loglevel;
3641 tmp_event[count].type = (enum lttng_event_type) LTTNG_UST_TRACEPOINT;
3642 tmp_event[count].pid = app->pid;
3643 tmp_event[count].enabled = -1;
3644 count++;
3645 }
3646 ret = ustctl_release_handle(app->sock, handle);
3647 pthread_mutex_unlock(&app->sock_lock);
3648 if (ret < 0 && ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
3649 ERR("Error releasing app handle for app %d with ret %d", app->sock, ret);
3650 }
3651 }
3652
3653 ret = count;
3654 *events = tmp_event;
3655
3656 DBG2("UST app list events done (%zu events)", count);
3657
3658 rcu_error:
3659 rcu_read_unlock();
3660 error:
3661 health_code_update();
3662 return ret;
3663 }
3664
3665 /*
3666 * Fill events array with all events name of all registered apps.
3667 */
3668 int ust_app_list_event_fields(struct lttng_event_field **fields)
3669 {
3670 int ret, handle;
3671 size_t nbmem, count = 0;
3672 struct lttng_ht_iter iter;
3673 struct ust_app *app;
3674 struct lttng_event_field *tmp_event;
3675
3676 nbmem = UST_APP_EVENT_LIST_SIZE;
3677 tmp_event = zmalloc(nbmem * sizeof(struct lttng_event_field));
3678 if (tmp_event == NULL) {
3679 PERROR("zmalloc ust app event fields");
3680 ret = -ENOMEM;
3681 goto error;
3682 }
3683
3684 rcu_read_lock();
3685
3686 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
3687 struct lttng_ust_field_iter uiter;
3688
3689 health_code_update();
3690
3691 if (!app->compatible) {
3692 /*
3693 * TODO: In time, we should notice the caller of this error by
3694 * telling him that this is a version error.
3695 */
3696 continue;
3697 }
3698 pthread_mutex_lock(&app->sock_lock);
3699 handle = ustctl_tracepoint_field_list(app->sock);
3700 if (handle < 0) {
3701 if (handle != -EPIPE && handle != -LTTNG_UST_ERR_EXITING) {
3702 ERR("UST app list field getting handle failed for app pid %d",
3703 app->pid);
3704 }
3705 pthread_mutex_unlock(&app->sock_lock);
3706 continue;
3707 }
3708
3709 while ((ret = ustctl_tracepoint_field_list_get(app->sock, handle,
3710 &uiter)) != -LTTNG_UST_ERR_NOENT) {
3711 /* Handle ustctl error. */
3712 if (ret < 0) {
3713 int release_ret;
3714
3715 if (ret != -LTTNG_UST_ERR_EXITING && ret != -EPIPE) {
3716 ERR("UST app tp list field failed for app %d with ret %d",
3717 app->sock, ret);
3718 } else {
3719 DBG3("UST app tp list field failed. Application is dead");
3720 /*
3721 * This is normal behavior, an application can die during the
3722 * creation process. Don't report an error so the execution can
3723 * continue normally. Reset list and count for next app.
3724 */
3725 break;
3726 }
3727 free(tmp_event);
3728 release_ret = ustctl_release_handle(app->sock, handle);
3729 pthread_mutex_unlock(&app->sock_lock);
3730 if (release_ret < 0 &&
3731 release_ret != -LTTNG_UST_ERR_EXITING &&
3732 release_ret != -EPIPE) {
3733 ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret);
3734 }
3735 goto rcu_error;
3736 }
3737
3738 health_code_update();
3739 if (count >= nbmem) {
3740 /* In case the realloc fails, we free the memory */
3741 struct lttng_event_field *new_tmp_event;
3742 size_t new_nbmem;
3743
3744 new_nbmem = nbmem << 1;
3745 DBG2("Reallocating event field list from %zu to %zu entries",
3746 nbmem, new_nbmem);
3747 new_tmp_event = realloc(tmp_event,
3748 new_nbmem * sizeof(struct lttng_event_field));
3749 if (new_tmp_event == NULL) {
3750 int release_ret;
3751
3752 PERROR("realloc ust app event fields");
3753 free(tmp_event);
3754 ret = -ENOMEM;
3755 release_ret = ustctl_release_handle(app->sock, handle);
3756 pthread_mutex_unlock(&app->sock_lock);
3757 if (release_ret &&
3758 release_ret != -LTTNG_UST_ERR_EXITING &&
3759 release_ret != -EPIPE) {
3760 ERR("Error releasing app handle for app %d with ret %d", app->sock, release_ret);
3761 }
3762 goto rcu_error;
3763 }
3764 /* Zero the new memory */
3765 memset(new_tmp_event + nbmem, 0,
3766 (new_nbmem - nbmem) * sizeof(struct lttng_event_field));
3767 nbmem = new_nbmem;
3768 tmp_event = new_tmp_event;
3769 }
3770
3771 memcpy(tmp_event[count].field_name, uiter.field_name, LTTNG_UST_SYM_NAME_LEN);
3772 /* Mapping between these enums matches 1 to 1. */
3773 tmp_event[count].type = (enum lttng_event_field_type) uiter.type;
3774 tmp_event[count].nowrite = uiter.nowrite;
3775
3776 memcpy(tmp_event[count].event.name, uiter.event_name, LTTNG_UST_SYM_NAME_LEN);
3777 tmp_event[count].event.loglevel = uiter.loglevel;
3778 tmp_event[count].event.type = LTTNG_EVENT_TRACEPOINT;
3779 tmp_event[count].event.pid = app->pid;
3780 tmp_event[count].event.enabled = -1;
3781 count++;
3782 }
3783 ret = ustctl_release_handle(app->sock, handle);
3784 pthread_mutex_unlock(&app->sock_lock);
3785 if (ret < 0 &&
3786 ret != -LTTNG_UST_ERR_EXITING &&
3787 ret != -EPIPE) {
3788 ERR("Error releasing app handle for app %d with ret %d", app->sock, ret);
3789 }
3790 }
3791
3792 ret = count;
3793 *fields = tmp_event;
3794
3795 DBG2("UST app list event fields done (%zu events)", count);
3796
3797 rcu_error:
3798 rcu_read_unlock();
3799 error:
3800 health_code_update();
3801 return ret;
3802 }
3803
3804 /*
3805 * Free and clean all traceable apps of the global list.
3806 *
3807 * Should _NOT_ be called with RCU read-side lock held.
3808 */
3809 void ust_app_clean_list(void)
3810 {
3811 int ret;
3812 struct ust_app *app;
3813 struct lttng_ht_iter iter;
3814
3815 DBG2("UST app cleaning registered apps hash table");
3816
3817 rcu_read_lock();
3818
3819 if (ust_app_ht) {
3820 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
3821 ret = lttng_ht_del(ust_app_ht, &iter);
3822 assert(!ret);
3823 call_rcu(&app->pid_n.head, delete_ust_app_rcu);
3824 }
3825 }
3826
3827 /* Cleanup socket hash table */
3828 if (ust_app_ht_by_sock) {
3829 cds_lfht_for_each_entry(ust_app_ht_by_sock->ht, &iter.iter, app,
3830 sock_n.node) {
3831 ret = lttng_ht_del(ust_app_ht_by_sock, &iter);
3832 assert(!ret);
3833 }
3834 }
3835
3836 /* Cleanup notify socket hash table */
3837 if (ust_app_ht_by_notify_sock) {
3838 cds_lfht_for_each_entry(ust_app_ht_by_notify_sock->ht, &iter.iter, app,
3839 notify_sock_n.node) {
3840 ret = lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
3841 assert(!ret);
3842 }
3843 }
3844 rcu_read_unlock();
3845
3846 /* Destroy is done only when the ht is empty */
3847 if (ust_app_ht) {
3848 ht_cleanup_push(ust_app_ht);
3849 }
3850 if (ust_app_ht_by_sock) {
3851 ht_cleanup_push(ust_app_ht_by_sock);
3852 }
3853 if (ust_app_ht_by_notify_sock) {
3854 ht_cleanup_push(ust_app_ht_by_notify_sock);
3855 }
3856 }
3857
3858 /*
3859 * Init UST app hash table.
3860 */
3861 int ust_app_ht_alloc(void)
3862 {
3863 ust_app_ht = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
3864 if (!ust_app_ht) {
3865 return -1;
3866 }
3867 ust_app_ht_by_sock = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
3868 if (!ust_app_ht_by_sock) {
3869 return -1;
3870 }
3871 ust_app_ht_by_notify_sock = lttng_ht_new(0, LTTNG_HT_TYPE_ULONG);
3872 if (!ust_app_ht_by_notify_sock) {
3873 return -1;
3874 }
3875 return 0;
3876 }
3877
3878 /*
3879 * For a specific UST session, disable the channel for all registered apps.
3880 */
3881 int ust_app_disable_channel_glb(struct ltt_ust_session *usess,
3882 struct ltt_ust_channel *uchan)
3883 {
3884 int ret = 0;
3885 struct lttng_ht_iter iter;
3886 struct lttng_ht_node_str *ua_chan_node;
3887 struct ust_app *app;
3888 struct ust_app_session *ua_sess;
3889 struct ust_app_channel *ua_chan;
3890
3891 if (usess == NULL || uchan == NULL) {
3892 ERR("Disabling UST global channel with NULL values");
3893 ret = -1;
3894 goto error;
3895 }
3896
3897 DBG2("UST app disabling channel %s from global domain for session id %" PRIu64,
3898 uchan->name, usess->id);
3899
3900 rcu_read_lock();
3901
3902 /* For every registered applications */
3903 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
3904 struct lttng_ht_iter uiter;
3905 if (!app->compatible) {
3906 /*
3907 * TODO: In time, we should notice the caller of this error by
3908 * telling him that this is a version error.
3909 */
3910 continue;
3911 }
3912 ua_sess = lookup_session_by_app(usess, app);
3913 if (ua_sess == NULL) {
3914 continue;
3915 }
3916
3917 /* Get channel */
3918 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
3919 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
3920 /* If the session if found for the app, the channel must be there */
3921 assert(ua_chan_node);
3922
3923 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
3924 /* The channel must not be already disabled */
3925 assert(ua_chan->enabled == 1);
3926
3927 /* Disable channel onto application */
3928 ret = disable_ust_app_channel(ua_sess, ua_chan, app);
3929 if (ret < 0) {
3930 /* XXX: We might want to report this error at some point... */
3931 continue;
3932 }
3933 }
3934
3935 rcu_read_unlock();
3936
3937 error:
3938 return ret;
3939 }
3940
3941 /*
3942 * For a specific UST session, enable the channel for all registered apps.
3943 */
3944 int ust_app_enable_channel_glb(struct ltt_ust_session *usess,
3945 struct ltt_ust_channel *uchan)
3946 {
3947 int ret = 0;
3948 struct lttng_ht_iter iter;
3949 struct ust_app *app;
3950 struct ust_app_session *ua_sess;
3951
3952 if (usess == NULL || uchan == NULL) {
3953 ERR("Adding UST global channel to NULL values");
3954 ret = -1;
3955 goto error;
3956 }
3957
3958 DBG2("UST app enabling channel %s to global domain for session id %" PRIu64,
3959 uchan->name, usess->id);
3960
3961 rcu_read_lock();
3962
3963 /* For every registered applications */
3964 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
3965 if (!app->compatible) {
3966 /*
3967 * TODO: In time, we should notice the caller of this error by
3968 * telling him that this is a version error.
3969 */
3970 continue;
3971 }
3972 ua_sess = lookup_session_by_app(usess, app);
3973 if (ua_sess == NULL) {
3974 continue;
3975 }
3976
3977 /* Enable channel onto application */
3978 ret = enable_ust_app_channel(ua_sess, uchan, app);
3979 if (ret < 0) {
3980 /* XXX: We might want to report this error at some point... */
3981 continue;
3982 }
3983 }
3984
3985 rcu_read_unlock();
3986
3987 error:
3988 return ret;
3989 }
3990
3991 /*
3992 * Disable an event in a channel and for a specific session.
3993 */
3994 int ust_app_disable_event_glb(struct ltt_ust_session *usess,
3995 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
3996 {
3997 int ret = 0;
3998 struct lttng_ht_iter iter, uiter;
3999 struct lttng_ht_node_str *ua_chan_node;
4000 struct ust_app *app;
4001 struct ust_app_session *ua_sess;
4002 struct ust_app_channel *ua_chan;
4003 struct ust_app_event *ua_event;
4004
4005 DBG("UST app disabling event %s for all apps in channel "
4006 "%s for session id %" PRIu64,
4007 uevent->attr.name, uchan->name, usess->id);
4008
4009 rcu_read_lock();
4010
4011 /* For all registered applications */
4012 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4013 if (!app->compatible) {
4014 /*
4015 * TODO: In time, we should notice the caller of this error by
4016 * telling him that this is a version error.
4017 */
4018 continue;
4019 }
4020 ua_sess = lookup_session_by_app(usess, app);
4021 if (ua_sess == NULL) {
4022 /* Next app */
4023 continue;
4024 }
4025
4026 /* Lookup channel in the ust app session */
4027 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
4028 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
4029 if (ua_chan_node == NULL) {
4030 DBG2("Channel %s not found in session id %" PRIu64 " for app pid %d."
4031 "Skipping", uchan->name, usess->id, app->pid);
4032 continue;
4033 }
4034 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
4035
4036 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
4037 uevent->filter, uevent->attr.loglevel,
4038 uevent->exclusion);
4039 if (ua_event == NULL) {
4040 DBG2("Event %s not found in channel %s for app pid %d."
4041 "Skipping", uevent->attr.name, uchan->name, app->pid);
4042 continue;
4043 }
4044
4045 ret = disable_ust_app_event(ua_sess, ua_event, app);
4046 if (ret < 0) {
4047 /* XXX: Report error someday... */
4048 continue;
4049 }
4050 }
4051
4052 rcu_read_unlock();
4053
4054 return ret;
4055 }
4056
4057 /*
4058 * For a specific UST session, create the channel for all registered apps.
4059 */
4060 int ust_app_create_channel_glb(struct ltt_ust_session *usess,
4061 struct ltt_ust_channel *uchan)
4062 {
4063 int ret = 0, created;
4064 struct lttng_ht_iter iter;
4065 struct ust_app *app;
4066 struct ust_app_session *ua_sess = NULL;
4067
4068 /* Very wrong code flow */
4069 assert(usess);
4070 assert(uchan);
4071
4072 DBG2("UST app adding channel %s to UST domain for session id %" PRIu64,
4073 uchan->name, usess->id);
4074
4075 rcu_read_lock();
4076
4077 /* For every registered applications */
4078 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4079 if (!app->compatible) {
4080 /*
4081 * TODO: In time, we should notice the caller of this error by
4082 * telling him that this is a version error.
4083 */
4084 continue;
4085 }
4086 if (!trace_ust_pid_tracker_lookup(usess, app->pid)) {
4087 /* Skip. */
4088 continue;
4089 }
4090
4091 /*
4092 * Create session on the tracer side and add it to app session HT. Note
4093 * that if session exist, it will simply return a pointer to the ust
4094 * app session.
4095 */
4096 ret = create_ust_app_session(usess, app, &ua_sess, &created);
4097 if (ret < 0) {
4098 switch (ret) {
4099 case -ENOTCONN:
4100 /*
4101 * The application's socket is not valid. Either a bad socket
4102 * or a timeout on it. We can't inform the caller that for a
4103 * specific app, the session failed so lets continue here.
4104 */
4105 ret = 0; /* Not an error. */
4106 continue;
4107 case -ENOMEM:
4108 default:
4109 goto error_rcu_unlock;
4110 }
4111 }
4112 assert(ua_sess);
4113
4114 pthread_mutex_lock(&ua_sess->lock);
4115
4116 if (ua_sess->deleted) {
4117 pthread_mutex_unlock(&ua_sess->lock);
4118 continue;
4119 }
4120
4121 if (!strncmp(uchan->name, DEFAULT_METADATA_NAME,
4122 sizeof(uchan->name))) {
4123 copy_channel_attr_to_ustctl(&ua_sess->metadata_attr, &uchan->attr);
4124 ret = 0;
4125 } else {
4126 /* Create channel onto application. We don't need the chan ref. */
4127 ret = create_ust_app_channel(ua_sess, uchan, app,
4128 LTTNG_UST_CHAN_PER_CPU, usess, NULL);
4129 }
4130 pthread_mutex_unlock(&ua_sess->lock);
4131 if (ret < 0) {
4132 /* Cleanup the created session if it's the case. */
4133 if (created) {
4134 destroy_app_session(app, ua_sess);
4135 }
4136 switch (ret) {
4137 case -ENOTCONN:
4138 /*
4139 * The application's socket is not valid. Either a bad socket
4140 * or a timeout on it. We can't inform the caller that for a
4141 * specific app, the session failed so lets continue here.
4142 */
4143 ret = 0; /* Not an error. */
4144 continue;
4145 case -ENOMEM:
4146 default:
4147 goto error_rcu_unlock;
4148 }
4149 }
4150 }
4151
4152 error_rcu_unlock:
4153 rcu_read_unlock();
4154 return ret;
4155 }
4156
4157 /*
4158 * Enable event for a specific session and channel on the tracer.
4159 */
4160 int ust_app_enable_event_glb(struct ltt_ust_session *usess,
4161 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
4162 {
4163 int ret = 0;
4164 struct lttng_ht_iter iter, uiter;
4165 struct lttng_ht_node_str *ua_chan_node;
4166 struct ust_app *app;
4167 struct ust_app_session *ua_sess;
4168 struct ust_app_channel *ua_chan;
4169 struct ust_app_event *ua_event;
4170
4171 DBG("UST app enabling event %s for all apps for session id %" PRIu64,
4172 uevent->attr.name, usess->id);
4173
4174 /*
4175 * NOTE: At this point, this function is called only if the session and
4176 * channel passed are already created for all apps. and enabled on the
4177 * tracer also.
4178 */
4179
4180 rcu_read_lock();
4181
4182 /* For all registered applications */
4183 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4184 if (!app->compatible) {
4185 /*
4186 * TODO: In time, we should notice the caller of this error by
4187 * telling him that this is a version error.
4188 */
4189 continue;
4190 }
4191 ua_sess = lookup_session_by_app(usess, app);
4192 if (!ua_sess) {
4193 /* The application has problem or is probably dead. */
4194 continue;
4195 }
4196
4197 pthread_mutex_lock(&ua_sess->lock);
4198
4199 if (ua_sess->deleted) {
4200 pthread_mutex_unlock(&ua_sess->lock);
4201 continue;
4202 }
4203
4204 /* Lookup channel in the ust app session */
4205 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
4206 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
4207 /*
4208 * It is possible that the channel cannot be found is
4209 * the channel/event creation occurs concurrently with
4210 * an application exit.
4211 */
4212 if (!ua_chan_node) {
4213 pthread_mutex_unlock(&ua_sess->lock);
4214 continue;
4215 }
4216
4217 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
4218
4219 /* Get event node */
4220 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
4221 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
4222 if (ua_event == NULL) {
4223 DBG3("UST app enable event %s not found for app PID %d."
4224 "Skipping app", uevent->attr.name, app->pid);
4225 goto next_app;
4226 }
4227
4228 ret = enable_ust_app_event(ua_sess, ua_event, app);
4229 if (ret < 0) {
4230 pthread_mutex_unlock(&ua_sess->lock);
4231 goto error;
4232 }
4233 next_app:
4234 pthread_mutex_unlock(&ua_sess->lock);
4235 }
4236
4237 error:
4238 rcu_read_unlock();
4239 return ret;
4240 }
4241
4242 /*
4243 * For a specific existing UST session and UST channel, creates the event for
4244 * all registered apps.
4245 */
4246 int ust_app_create_event_glb(struct ltt_ust_session *usess,
4247 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent)
4248 {
4249 int ret = 0;
4250 struct lttng_ht_iter iter, uiter;
4251 struct lttng_ht_node_str *ua_chan_node;
4252 struct ust_app *app;
4253 struct ust_app_session *ua_sess;
4254 struct ust_app_channel *ua_chan;
4255
4256 DBG("UST app creating event %s for all apps for session id %" PRIu64,
4257 uevent->attr.name, usess->id);
4258
4259 rcu_read_lock();
4260
4261 /* For all registered applications */
4262 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4263 if (!app->compatible) {
4264 /*
4265 * TODO: In time, we should notice the caller of this error by
4266 * telling him that this is a version error.
4267 */
4268 continue;
4269 }
4270 ua_sess = lookup_session_by_app(usess, app);
4271 if (!ua_sess) {
4272 /* The application has problem or is probably dead. */
4273 continue;
4274 }
4275
4276 pthread_mutex_lock(&ua_sess->lock);
4277
4278 if (ua_sess->deleted) {
4279 pthread_mutex_unlock(&ua_sess->lock);
4280 continue;
4281 }
4282
4283 /* Lookup channel in the ust app session */
4284 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
4285 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
4286 /* If the channel is not found, there is a code flow error */
4287 assert(ua_chan_node);
4288
4289 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
4290
4291 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
4292 pthread_mutex_unlock(&ua_sess->lock);
4293 if (ret < 0) {
4294 if (ret != -LTTNG_UST_ERR_EXIST) {
4295 /* Possible value at this point: -ENOMEM. If so, we stop! */
4296 break;
4297 }
4298 DBG2("UST app event %s already exist on app PID %d",
4299 uevent->attr.name, app->pid);
4300 continue;
4301 }
4302 }
4303
4304 rcu_read_unlock();
4305
4306 return ret;
4307 }
4308
4309 /*
4310 * Start tracing for a specific UST session and app.
4311 */
4312 static
4313 int ust_app_start_trace(struct ltt_ust_session *usess, struct ust_app *app)
4314 {
4315 int ret = 0;
4316 struct ust_app_session *ua_sess;
4317
4318 DBG("Starting tracing for ust app pid %d", app->pid);
4319
4320 rcu_read_lock();
4321
4322 if (!app->compatible) {
4323 goto end;
4324 }
4325
4326 ua_sess = lookup_session_by_app(usess, app);
4327 if (ua_sess == NULL) {
4328 /* The session is in teardown process. Ignore and continue. */
4329 goto end;
4330 }
4331
4332 pthread_mutex_lock(&ua_sess->lock);
4333
4334 if (ua_sess->deleted) {
4335 pthread_mutex_unlock(&ua_sess->lock);
4336 goto end;
4337 }
4338
4339 /* Upon restart, we skip the setup, already done */
4340 if (ua_sess->started) {
4341 goto skip_setup;
4342 }
4343
4344 /* Create directories if consumer is LOCAL and has a path defined. */
4345 if (usess->consumer->type == CONSUMER_DST_LOCAL &&
4346 strlen(usess->consumer->dst.trace_path) > 0) {
4347 ret = run_as_mkdir_recursive(usess->consumer->dst.trace_path,
4348 S_IRWXU | S_IRWXG, ua_sess->euid, ua_sess->egid);
4349 if (ret < 0) {
4350 if (errno != EEXIST) {
4351 ERR("Trace directory creation error");
4352 goto error_unlock;
4353 }
4354 }
4355 }
4356
4357 /*
4358 * Create the metadata for the application. This returns gracefully if a
4359 * metadata was already set for the session.
4360 */
4361 ret = create_ust_app_metadata(ua_sess, app, usess->consumer);
4362 if (ret < 0) {
4363 goto error_unlock;
4364 }
4365
4366 health_code_update();
4367
4368 skip_setup:
4369 /* This start the UST tracing */
4370 pthread_mutex_lock(&app->sock_lock);
4371 ret = ustctl_start_session(app->sock, ua_sess->handle);
4372 pthread_mutex_unlock(&app->sock_lock);
4373 if (ret < 0) {
4374 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
4375 ERR("Error starting tracing for app pid: %d (ret: %d)",
4376 app->pid, ret);
4377 } else {
4378 DBG("UST app start session failed. Application is dead.");
4379 /*
4380 * This is normal behavior, an application can die during the
4381 * creation process. Don't report an error so the execution can
4382 * continue normally.
4383 */
4384 pthread_mutex_unlock(&ua_sess->lock);
4385 goto end;
4386 }
4387 goto error_unlock;
4388 }
4389
4390 /* Indicate that the session has been started once */
4391 ua_sess->started = 1;
4392
4393 pthread_mutex_unlock(&ua_sess->lock);
4394
4395 health_code_update();
4396
4397 /* Quiescent wait after starting trace */
4398 pthread_mutex_lock(&app->sock_lock);
4399 ret = ustctl_wait_quiescent(app->sock);
4400 pthread_mutex_unlock(&app->sock_lock);
4401 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
4402 ERR("UST app wait quiescent failed for app pid %d ret %d",
4403 app->pid, ret);
4404 }
4405
4406 end:
4407 rcu_read_unlock();
4408 health_code_update();
4409 return 0;
4410
4411 error_unlock:
4412 pthread_mutex_unlock(&ua_sess->lock);
4413 rcu_read_unlock();
4414 health_code_update();
4415 return -1;
4416 }
4417
4418 /*
4419 * Stop tracing for a specific UST session and app.
4420 */
4421 static
4422 int ust_app_stop_trace(struct ltt_ust_session *usess, struct ust_app *app)
4423 {
4424 int ret = 0;
4425 struct ust_app_session *ua_sess;
4426 struct ust_registry_session *registry;
4427
4428 DBG("Stopping tracing for ust app pid %d", app->pid);
4429
4430 rcu_read_lock();
4431
4432 if (!app->compatible) {
4433 goto end_no_session;
4434 }
4435
4436 ua_sess = lookup_session_by_app(usess, app);
4437 if (ua_sess == NULL) {
4438 goto end_no_session;
4439 }
4440
4441 pthread_mutex_lock(&ua_sess->lock);
4442
4443 if (ua_sess->deleted) {
4444 pthread_mutex_unlock(&ua_sess->lock);
4445 goto end_no_session;
4446 }
4447
4448 /*
4449 * If started = 0, it means that stop trace has been called for a session
4450 * that was never started. It's possible since we can have a fail start
4451 * from either the application manager thread or the command thread. Simply
4452 * indicate that this is a stop error.
4453 */
4454 if (!ua_sess->started) {
4455 goto error_rcu_unlock;
4456 }
4457
4458 health_code_update();
4459
4460 /* This inhibits UST tracing */
4461 pthread_mutex_lock(&app->sock_lock);
4462 ret = ustctl_stop_session(app->sock, ua_sess->handle);
4463 pthread_mutex_unlock(&app->sock_lock);
4464 if (ret < 0) {
4465 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
4466 ERR("Error stopping tracing for app pid: %d (ret: %d)",
4467 app->pid, ret);
4468 } else {
4469 DBG("UST app stop session failed. Application is dead.");
4470 /*
4471 * This is normal behavior, an application can die during the
4472 * creation process. Don't report an error so the execution can
4473 * continue normally.
4474 */
4475 goto end_unlock;
4476 }
4477 goto error_rcu_unlock;
4478 }
4479
4480 health_code_update();
4481
4482 /* Quiescent wait after stopping trace */
4483 pthread_mutex_lock(&app->sock_lock);
4484 ret = ustctl_wait_quiescent(app->sock);
4485 pthread_mutex_unlock(&app->sock_lock);
4486 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
4487 ERR("UST app wait quiescent failed for app pid %d ret %d",
4488 app->pid, ret);
4489 }
4490
4491 health_code_update();
4492
4493 registry = get_session_registry(ua_sess);
4494 assert(registry);
4495
4496 /* Push metadata for application before freeing the application. */
4497 (void) push_metadata(registry, ua_sess->consumer);
4498
4499 end_unlock:
4500 pthread_mutex_unlock(&ua_sess->lock);
4501 end_no_session:
4502 rcu_read_unlock();
4503 health_code_update();
4504 return 0;
4505
4506 error_rcu_unlock:
4507 pthread_mutex_unlock(&ua_sess->lock);
4508 rcu_read_unlock();
4509 health_code_update();
4510 return -1;
4511 }
4512
4513 static
4514 int ust_app_flush_app_session(struct ust_app *app,
4515 struct ust_app_session *ua_sess)
4516 {
4517 int ret, retval = 0;
4518 struct lttng_ht_iter iter;
4519 struct ust_app_channel *ua_chan;
4520 struct consumer_socket *socket;
4521
4522 DBG("Flushing app session buffers for ust app pid %d", app->pid);
4523
4524 rcu_read_lock();
4525
4526 if (!app->compatible) {
4527 goto end_not_compatible;
4528 }
4529
4530 pthread_mutex_lock(&ua_sess->lock);
4531
4532 if (ua_sess->deleted) {
4533 goto end_deleted;
4534 }
4535
4536 health_code_update();
4537
4538 /* Flushing buffers */
4539 socket = consumer_find_socket_by_bitness(app->bits_per_long,
4540 ua_sess->consumer);
4541
4542 /* Flush buffers and push metadata. */
4543 switch (ua_sess->buffer_type) {
4544 case LTTNG_BUFFER_PER_PID:
4545 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
4546 node.node) {
4547 health_code_update();
4548 ret = consumer_flush_channel(socket, ua_chan->key);
4549 if (ret) {
4550 ERR("Error flushing consumer channel");
4551 retval = -1;
4552 continue;
4553 }
4554 }
4555 break;
4556 case LTTNG_BUFFER_PER_UID:
4557 default:
4558 assert(0);
4559 break;
4560 }
4561
4562 health_code_update();
4563
4564 end_deleted:
4565 pthread_mutex_unlock(&ua_sess->lock);
4566
4567 end_not_compatible:
4568 rcu_read_unlock();
4569 health_code_update();
4570 return retval;
4571 }
4572
4573 /*
4574 * Flush buffers for all applications for a specific UST session.
4575 * Called with UST session lock held.
4576 */
4577 static
4578 int ust_app_flush_session(struct ltt_ust_session *usess)
4579
4580 {
4581 int ret = 0;
4582
4583 DBG("Flushing session buffers for all ust apps");
4584
4585 rcu_read_lock();
4586
4587 /* Flush buffers and push metadata. */
4588 switch (usess->buffer_type) {
4589 case LTTNG_BUFFER_PER_UID:
4590 {
4591 struct buffer_reg_uid *reg;
4592 struct lttng_ht_iter iter;
4593
4594 /* Flush all per UID buffers associated to that session. */
4595 cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
4596 struct ust_registry_session *ust_session_reg;
4597 struct buffer_reg_channel *reg_chan;
4598 struct consumer_socket *socket;
4599
4600 /* Get consumer socket to use to push the metadata.*/
4601 socket = consumer_find_socket_by_bitness(reg->bits_per_long,
4602 usess->consumer);
4603 if (!socket) {
4604 /* Ignore request if no consumer is found for the session. */
4605 continue;
4606 }
4607
4608 cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter,
4609 reg_chan, node.node) {
4610 /*
4611 * The following call will print error values so the return
4612 * code is of little importance because whatever happens, we
4613 * have to try them all.
4614 */
4615 (void) consumer_flush_channel(socket, reg_chan->consumer_key);
4616 }
4617
4618 ust_session_reg = reg->registry->reg.ust;
4619 /* Push metadata. */
4620 (void) push_metadata(ust_session_reg, usess->consumer);
4621 }
4622 break;
4623 }
4624 case LTTNG_BUFFER_PER_PID:
4625 {
4626 struct ust_app_session *ua_sess;
4627 struct lttng_ht_iter iter;
4628 struct ust_app *app;
4629
4630 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4631 ua_sess = lookup_session_by_app(usess, app);
4632 if (ua_sess == NULL) {
4633 continue;
4634 }
4635 (void) ust_app_flush_app_session(app, ua_sess);
4636 }
4637 break;
4638 }
4639 default:
4640 ret = -1;
4641 assert(0);
4642 break;
4643 }
4644
4645 rcu_read_unlock();
4646 health_code_update();
4647 return ret;
4648 }
4649
4650 /*
4651 * Destroy a specific UST session in apps.
4652 */
4653 static int destroy_trace(struct ltt_ust_session *usess, struct ust_app *app)
4654 {
4655 int ret;
4656 struct ust_app_session *ua_sess;
4657 struct lttng_ht_iter iter;
4658 struct lttng_ht_node_u64 *node;
4659
4660 DBG("Destroy tracing for ust app pid %d", app->pid);
4661
4662 rcu_read_lock();
4663
4664 if (!app->compatible) {
4665 goto end;
4666 }
4667
4668 __lookup_session_by_app(usess, app, &iter);
4669 node = lttng_ht_iter_get_node_u64(&iter);
4670 if (node == NULL) {
4671 /* Session is being or is deleted. */
4672 goto end;
4673 }
4674 ua_sess = caa_container_of(node, struct ust_app_session, node);
4675
4676 health_code_update();
4677 destroy_app_session(app, ua_sess);
4678
4679 health_code_update();
4680
4681 /* Quiescent wait after stopping trace */
4682 pthread_mutex_lock(&app->sock_lock);
4683 ret = ustctl_wait_quiescent(app->sock);
4684 pthread_mutex_unlock(&app->sock_lock);
4685 if (ret < 0 && ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
4686 ERR("UST app wait quiescent failed for app pid %d ret %d",
4687 app->pid, ret);
4688 }
4689 end:
4690 rcu_read_unlock();
4691 health_code_update();
4692 return 0;
4693 }
4694
4695 /*
4696 * Start tracing for the UST session.
4697 */
4698 int ust_app_start_trace_all(struct ltt_ust_session *usess)
4699 {
4700 int ret = 0;
4701 struct lttng_ht_iter iter;
4702 struct ust_app *app;
4703
4704 DBG("Starting all UST traces");
4705
4706 rcu_read_lock();
4707
4708 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4709 ret = ust_app_start_trace(usess, app);
4710 if (ret < 0) {
4711 /* Continue to next apps even on error */
4712 continue;
4713 }
4714 }
4715
4716 rcu_read_unlock();
4717
4718 return 0;
4719 }
4720
4721 /*
4722 * Start tracing for the UST session.
4723 * Called with UST session lock held.
4724 */
4725 int ust_app_stop_trace_all(struct ltt_ust_session *usess)
4726 {
4727 int ret = 0;
4728 struct lttng_ht_iter iter;
4729 struct ust_app *app;
4730
4731 DBG("Stopping all UST traces");
4732
4733 rcu_read_lock();
4734
4735 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4736 ret = ust_app_stop_trace(usess, app);
4737 if (ret < 0) {
4738 /* Continue to next apps even on error */
4739 continue;
4740 }
4741 }
4742
4743 (void) ust_app_flush_session(usess);
4744
4745 rcu_read_unlock();
4746
4747 return 0;
4748 }
4749
4750 /*
4751 * Destroy app UST session.
4752 */
4753 int ust_app_destroy_trace_all(struct ltt_ust_session *usess)
4754 {
4755 int ret = 0;
4756 struct lttng_ht_iter iter;
4757 struct ust_app *app;
4758
4759 DBG("Destroy all UST traces");
4760
4761 rcu_read_lock();
4762
4763 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4764 ret = destroy_trace(usess, app);
4765 if (ret < 0) {
4766 /* Continue to next apps even on error */
4767 continue;
4768 }
4769 }
4770
4771 rcu_read_unlock();
4772
4773 return 0;
4774 }
4775
4776 static
4777 void ust_app_global_create(struct ltt_ust_session *usess, struct ust_app *app)
4778 {
4779 int ret = 0;
4780 struct lttng_ht_iter iter, uiter;
4781 struct ust_app_session *ua_sess = NULL;
4782 struct ust_app_channel *ua_chan;
4783 struct ust_app_event *ua_event;
4784 struct ust_app_ctx *ua_ctx;
4785 int is_created = 0;
4786
4787 ret = create_ust_app_session(usess, app, &ua_sess, &is_created);
4788 if (ret < 0) {
4789 /* Tracer is probably gone or ENOMEM. */
4790 goto error;
4791 }
4792 if (!is_created) {
4793 /* App session already created. */
4794 goto end;
4795 }
4796 assert(ua_sess);
4797
4798 pthread_mutex_lock(&ua_sess->lock);
4799
4800 if (ua_sess->deleted) {
4801 pthread_mutex_unlock(&ua_sess->lock);
4802 goto end;
4803 }
4804
4805 /*
4806 * We can iterate safely here over all UST app session since the create ust
4807 * app session above made a shadow copy of the UST global domain from the
4808 * ltt ust session.
4809 */
4810 cds_lfht_for_each_entry(ua_sess->channels->ht, &iter.iter, ua_chan,
4811 node.node) {
4812 ret = do_create_channel(app, usess, ua_sess, ua_chan);
4813 if (ret < 0 && ret != -ENOTCONN) {
4814 /*
4815 * Stop everything. On error, the application
4816 * failed, no more file descriptor are available
4817 * or ENOMEM so stopping here is the only thing
4818 * we can do for now. The only exception is
4819 * -ENOTCONN, which indicates that the application
4820 * has exit.
4821 */
4822 goto error_unlock;
4823 }
4824
4825 /*
4826 * Add context using the list so they are enabled in the same order the
4827 * user added them.
4828 */
4829 cds_list_for_each_entry(ua_ctx, &ua_chan->ctx_list, list) {
4830 ret = create_ust_channel_context(ua_chan, ua_ctx, app);
4831 if (ret < 0) {
4832 goto error_unlock;
4833 }
4834 }
4835
4836
4837 /* For each events */
4838 cds_lfht_for_each_entry(ua_chan->events->ht, &uiter.iter, ua_event,
4839 node.node) {
4840 ret = create_ust_event(app, ua_sess, ua_chan, ua_event);
4841 if (ret < 0) {
4842 goto error_unlock;
4843 }
4844 }
4845 }
4846
4847 pthread_mutex_unlock(&ua_sess->lock);
4848
4849 if (usess->active) {
4850 ret = ust_app_start_trace(usess, app);
4851 if (ret < 0) {
4852 goto error;
4853 }
4854
4855 DBG2("UST trace started for app pid %d", app->pid);
4856 }
4857 end:
4858 /* Everything went well at this point. */
4859 return;
4860
4861 error_unlock:
4862 pthread_mutex_unlock(&ua_sess->lock);
4863 error:
4864 if (ua_sess) {
4865 destroy_app_session(app, ua_sess);
4866 }
4867 return;
4868 }
4869
4870 static
4871 void ust_app_global_destroy(struct ltt_ust_session *usess, struct ust_app *app)
4872 {
4873 struct ust_app_session *ua_sess;
4874
4875 ua_sess = lookup_session_by_app(usess, app);
4876 if (ua_sess == NULL) {
4877 return;
4878 }
4879 destroy_app_session(app, ua_sess);
4880 }
4881
4882 /*
4883 * Add channels/events from UST global domain to registered apps at sock.
4884 *
4885 * Called with session lock held.
4886 * Called with RCU read-side lock held.
4887 */
4888 void ust_app_global_update(struct ltt_ust_session *usess, struct ust_app *app)
4889 {
4890 assert(usess);
4891
4892 DBG2("UST app global update for app sock %d for session id %" PRIu64,
4893 app->sock, usess->id);
4894
4895 if (!app->compatible) {
4896 return;
4897 }
4898
4899 if (trace_ust_pid_tracker_lookup(usess, app->pid)) {
4900 ust_app_global_create(usess, app);
4901 } else {
4902 ust_app_global_destroy(usess, app);
4903 }
4904 }
4905
4906 /*
4907 * Called with session lock held.
4908 */
4909 void ust_app_global_update_all(struct ltt_ust_session *usess)
4910 {
4911 struct lttng_ht_iter iter;
4912 struct ust_app *app;
4913
4914 rcu_read_lock();
4915 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4916 ust_app_global_update(usess, app);
4917 }
4918 rcu_read_unlock();
4919 }
4920
4921 /*
4922 * Add context to a specific channel for global UST domain.
4923 */
4924 int ust_app_add_ctx_channel_glb(struct ltt_ust_session *usess,
4925 struct ltt_ust_channel *uchan, struct ltt_ust_context *uctx)
4926 {
4927 int ret = 0;
4928 struct lttng_ht_node_str *ua_chan_node;
4929 struct lttng_ht_iter iter, uiter;
4930 struct ust_app_channel *ua_chan = NULL;
4931 struct ust_app_session *ua_sess;
4932 struct ust_app *app;
4933
4934 rcu_read_lock();
4935
4936 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
4937 if (!app->compatible) {
4938 /*
4939 * TODO: In time, we should notice the caller of this error by
4940 * telling him that this is a version error.
4941 */
4942 continue;
4943 }
4944 ua_sess = lookup_session_by_app(usess, app);
4945 if (ua_sess == NULL) {
4946 continue;
4947 }
4948
4949 pthread_mutex_lock(&ua_sess->lock);
4950
4951 if (ua_sess->deleted) {
4952 pthread_mutex_unlock(&ua_sess->lock);
4953 continue;
4954 }
4955
4956 /* Lookup channel in the ust app session */
4957 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &uiter);
4958 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
4959 if (ua_chan_node == NULL) {
4960 goto next_app;
4961 }
4962 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel,
4963 node);
4964 ret = create_ust_app_channel_context(ua_sess, ua_chan, &uctx->ctx, app);
4965 if (ret < 0) {
4966 goto next_app;
4967 }
4968 next_app:
4969 pthread_mutex_unlock(&ua_sess->lock);
4970 }
4971
4972 rcu_read_unlock();
4973 return ret;
4974 }
4975
4976 /*
4977 * Enable event for a channel from a UST session for a specific PID.
4978 */
4979 int ust_app_enable_event_pid(struct ltt_ust_session *usess,
4980 struct ltt_ust_channel *uchan, struct ltt_ust_event *uevent, pid_t pid)
4981 {
4982 int ret = 0;
4983 struct lttng_ht_iter iter;
4984 struct lttng_ht_node_str *ua_chan_node;
4985 struct ust_app *app;
4986 struct ust_app_session *ua_sess;
4987 struct ust_app_channel *ua_chan;
4988 struct ust_app_event *ua_event;
4989
4990 DBG("UST app enabling event %s for PID %d", uevent->attr.name, pid);
4991
4992 rcu_read_lock();
4993
4994 app = ust_app_find_by_pid(pid);
4995 if (app == NULL) {
4996 ERR("UST app enable event per PID %d not found", pid);
4997 ret = -1;
4998 goto end;
4999 }
5000
5001 if (!app->compatible) {
5002 ret = 0;
5003 goto end;
5004 }
5005
5006 ua_sess = lookup_session_by_app(usess, app);
5007 if (!ua_sess) {
5008 /* The application has problem or is probably dead. */
5009 ret = 0;
5010 goto end;
5011 }
5012
5013 pthread_mutex_lock(&ua_sess->lock);
5014
5015 if (ua_sess->deleted) {
5016 ret = 0;
5017 goto end_unlock;
5018 }
5019
5020 /* Lookup channel in the ust app session */
5021 lttng_ht_lookup(ua_sess->channels, (void *)uchan->name, &iter);
5022 ua_chan_node = lttng_ht_iter_get_node_str(&iter);
5023 /* If the channel is not found, there is a code flow error */
5024 assert(ua_chan_node);
5025
5026 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
5027
5028 ua_event = find_ust_app_event(ua_chan->events, uevent->attr.name,
5029 uevent->filter, uevent->attr.loglevel, uevent->exclusion);
5030 if (ua_event == NULL) {
5031 ret = create_ust_app_event(ua_sess, ua_chan, uevent, app);
5032 if (ret < 0) {
5033 goto end_unlock;
5034 }
5035 } else {
5036 ret = enable_ust_app_event(ua_sess, ua_event, app);
5037 if (ret < 0) {
5038 goto end_unlock;
5039 }
5040 }
5041
5042 end_unlock:
5043 pthread_mutex_unlock(&ua_sess->lock);
5044 end:
5045 rcu_read_unlock();
5046 return ret;
5047 }
5048
5049 /*
5050 * Calibrate registered applications.
5051 */
5052 int ust_app_calibrate_glb(struct lttng_ust_calibrate *calibrate)
5053 {
5054 int ret = 0;
5055 struct lttng_ht_iter iter;
5056 struct ust_app *app;
5057
5058 rcu_read_lock();
5059
5060 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
5061 if (!app->compatible) {
5062 /*
5063 * TODO: In time, we should notice the caller of this error by
5064 * telling him that this is a version error.
5065 */
5066 continue;
5067 }
5068
5069 health_code_update();
5070
5071 pthread_mutex_lock(&app->sock_lock);
5072 ret = ustctl_calibrate(app->sock, calibrate);
5073 pthread_mutex_unlock(&app->sock_lock);
5074 if (ret < 0) {
5075 switch (ret) {
5076 case -ENOSYS:
5077 /* Means that it's not implemented on the tracer side. */
5078 ret = 0;
5079 break;
5080 default:
5081 DBG2("Calibrate app PID %d returned with error %d",
5082 app->pid, ret);
5083 break;
5084 }
5085 }
5086 }
5087
5088 DBG("UST app global domain calibration finished");
5089
5090 rcu_read_unlock();
5091
5092 health_code_update();
5093
5094 return ret;
5095 }
5096
5097 /*
5098 * Receive registration and populate the given msg structure.
5099 *
5100 * On success return 0 else a negative value returned by the ustctl call.
5101 */
5102 int ust_app_recv_registration(int sock, struct ust_register_msg *msg)
5103 {
5104 int ret;
5105 uint32_t pid, ppid, uid, gid;
5106
5107 assert(msg);
5108
5109 ret = ustctl_recv_reg_msg(sock, &msg->type, &msg->major, &msg->minor,
5110 &pid, &ppid, &uid, &gid,
5111 &msg->bits_per_long,
5112 &msg->uint8_t_alignment,
5113 &msg->uint16_t_alignment,
5114 &msg->uint32_t_alignment,
5115 &msg->uint64_t_alignment,
5116 &msg->long_alignment,
5117 &msg->byte_order,
5118 msg->name);
5119 if (ret < 0) {
5120 switch (-ret) {
5121 case EPIPE:
5122 case ECONNRESET:
5123 case LTTNG_UST_ERR_EXITING:
5124 DBG3("UST app recv reg message failed. Application died");
5125 break;
5126 case LTTNG_UST_ERR_UNSUP_MAJOR:
5127 ERR("UST app recv reg unsupported version %d.%d. Supporting %d.%d",
5128 msg->major, msg->minor, LTTNG_UST_ABI_MAJOR_VERSION,
5129 LTTNG_UST_ABI_MINOR_VERSION);
5130 break;
5131 default:
5132 ERR("UST app recv reg message failed with ret %d", ret);
5133 break;
5134 }
5135 goto error;
5136 }
5137 msg->pid = (pid_t) pid;
5138 msg->ppid = (pid_t) ppid;
5139 msg->uid = (uid_t) uid;
5140 msg->gid = (gid_t) gid;
5141
5142 error:
5143 return ret;
5144 }
5145
5146 /*
5147 * Return a ust app session object using the application object and the
5148 * session object descriptor has a key. If not found, NULL is returned.
5149 * A RCU read side lock MUST be acquired when calling this function.
5150 */
5151 static struct ust_app_session *find_session_by_objd(struct ust_app *app,
5152 int objd)
5153 {
5154 struct lttng_ht_node_ulong *node;
5155 struct lttng_ht_iter iter;
5156 struct ust_app_session *ua_sess = NULL;
5157
5158 assert(app);
5159
5160 lttng_ht_lookup(app->ust_sessions_objd, (void *)((unsigned long) objd), &iter);
5161 node = lttng_ht_iter_get_node_ulong(&iter);
5162 if (node == NULL) {
5163 DBG2("UST app session find by objd %d not found", objd);
5164 goto error;
5165 }
5166
5167 ua_sess = caa_container_of(node, struct ust_app_session, ust_objd_node);
5168
5169 error:
5170 return ua_sess;
5171 }
5172
5173 /*
5174 * Return a ust app channel object using the application object and the channel
5175 * object descriptor has a key. If not found, NULL is returned. A RCU read side
5176 * lock MUST be acquired before calling this function.
5177 */
5178 static struct ust_app_channel *find_channel_by_objd(struct ust_app *app,
5179 int objd)
5180 {
5181 struct lttng_ht_node_ulong *node;
5182 struct lttng_ht_iter iter;
5183 struct ust_app_channel *ua_chan = NULL;
5184
5185 assert(app);
5186
5187 lttng_ht_lookup(app->ust_objd, (void *)((unsigned long) objd), &iter);
5188 node = lttng_ht_iter_get_node_ulong(&iter);
5189 if (node == NULL) {
5190 DBG2("UST app channel find by objd %d not found", objd);
5191 goto error;
5192 }
5193
5194 ua_chan = caa_container_of(node, struct ust_app_channel, ust_objd_node);
5195
5196 error:
5197 return ua_chan;
5198 }
5199
5200 /*
5201 * Reply to a register channel notification from an application on the notify
5202 * socket. The channel metadata is also created.
5203 *
5204 * The session UST registry lock is acquired in this function.
5205 *
5206 * On success 0 is returned else a negative value.
5207 */
5208 static int reply_ust_register_channel(int sock, int sobjd, int cobjd,
5209 size_t nr_fields, struct ustctl_field *fields)
5210 {
5211 int ret, ret_code = 0;
5212 uint32_t chan_id, reg_count;
5213 uint64_t chan_reg_key;
5214 enum ustctl_channel_header type;
5215 struct ust_app *app;
5216 struct ust_app_channel *ua_chan;
5217 struct ust_app_session *ua_sess;
5218 struct ust_registry_session *registry;
5219 struct ust_registry_channel *chan_reg;
5220
5221 rcu_read_lock();
5222
5223 /* Lookup application. If not found, there is a code flow error. */
5224 app = find_app_by_notify_sock(sock);
5225 if (!app) {
5226 DBG("Application socket %d is being teardown. Abort event notify",
5227 sock);
5228 ret = 0;
5229 free(fields);
5230 goto error_rcu_unlock;
5231 }
5232
5233 /* Lookup channel by UST object descriptor. */
5234 ua_chan = find_channel_by_objd(app, cobjd);
5235 if (!ua_chan) {
5236 DBG("Application channel is being teardown. Abort event notify");
5237 ret = 0;
5238 free(fields);
5239 goto error_rcu_unlock;
5240 }
5241
5242 assert(ua_chan->session);
5243 ua_sess = ua_chan->session;
5244
5245 /* Get right session registry depending on the session buffer type. */
5246 registry = get_session_registry(ua_sess);
5247 assert(registry);
5248
5249 /* Depending on the buffer type, a different channel key is used. */
5250 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) {
5251 chan_reg_key = ua_chan->tracing_channel_id;
5252 } else {
5253 chan_reg_key = ua_chan->key;
5254 }
5255
5256 pthread_mutex_lock(&registry->lock);
5257
5258 chan_reg = ust_registry_channel_find(registry, chan_reg_key);
5259 assert(chan_reg);
5260
5261 if (!chan_reg->register_done) {
5262 reg_count = ust_registry_get_event_count(chan_reg);
5263 if (reg_count < 31) {
5264 type = USTCTL_CHANNEL_HEADER_COMPACT;
5265 } else {
5266 type = USTCTL_CHANNEL_HEADER_LARGE;
5267 }
5268
5269 chan_reg->nr_ctx_fields = nr_fields;
5270 chan_reg->ctx_fields = fields;
5271 chan_reg->header_type = type;
5272 } else {
5273 /* Get current already assigned values. */
5274 type = chan_reg->header_type;
5275 free(fields);
5276 /* Set to NULL so the error path does not do a double free. */
5277 fields = NULL;
5278 }
5279 /* Channel id is set during the object creation. */
5280 chan_id = chan_reg->chan_id;
5281
5282 /* Append to metadata */
5283 if (!chan_reg->metadata_dumped) {
5284 ret_code = ust_metadata_channel_statedump(registry, chan_reg);
5285 if (ret_code) {
5286 ERR("Error appending channel metadata (errno = %d)", ret_code);
5287 goto reply;
5288 }
5289 }
5290
5291 reply:
5292 DBG3("UST app replying to register channel key %" PRIu64
5293 " with id %u, type: %d, ret: %d", chan_reg_key, chan_id, type,
5294 ret_code);
5295
5296 ret = ustctl_reply_register_channel(sock, chan_id, type, ret_code);
5297 if (ret < 0) {
5298 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5299 ERR("UST app reply channel failed with ret %d", ret);
5300 } else {
5301 DBG3("UST app reply channel failed. Application died");
5302 }
5303 goto error;
5304 }
5305
5306 /* This channel registry registration is completed. */
5307 chan_reg->register_done = 1;
5308
5309 error:
5310 pthread_mutex_unlock(&registry->lock);
5311 error_rcu_unlock:
5312 rcu_read_unlock();
5313 if (ret) {
5314 free(fields);
5315 }
5316 return ret;
5317 }
5318
5319 /*
5320 * Add event to the UST channel registry. When the event is added to the
5321 * registry, the metadata is also created. Once done, this replies to the
5322 * application with the appropriate error code.
5323 *
5324 * The session UST registry lock is acquired in the function.
5325 *
5326 * On success 0 is returned else a negative value.
5327 */
5328 static int add_event_ust_registry(int sock, int sobjd, int cobjd, char *name,
5329 char *sig, size_t nr_fields, struct ustctl_field *fields,
5330 int loglevel_value, char *model_emf_uri)
5331 {
5332 int ret, ret_code;
5333 uint32_t event_id = 0;
5334 uint64_t chan_reg_key;
5335 struct ust_app *app;
5336 struct ust_app_channel *ua_chan;
5337 struct ust_app_session *ua_sess;
5338 struct ust_registry_session *registry;
5339
5340 rcu_read_lock();
5341
5342 /* Lookup application. If not found, there is a code flow error. */
5343 app = find_app_by_notify_sock(sock);
5344 if (!app) {
5345 DBG("Application socket %d is being teardown. Abort event notify",
5346 sock);
5347 ret = 0;
5348 free(sig);
5349 free(fields);
5350 free(model_emf_uri);
5351 goto error_rcu_unlock;
5352 }
5353
5354 /* Lookup channel by UST object descriptor. */
5355 ua_chan = find_channel_by_objd(app, cobjd);
5356 if (!ua_chan) {
5357 DBG("Application channel is being teardown. Abort event notify");
5358 ret = 0;
5359 free(sig);
5360 free(fields);
5361 free(model_emf_uri);
5362 goto error_rcu_unlock;
5363 }
5364
5365 assert(ua_chan->session);
5366 ua_sess = ua_chan->session;
5367
5368 registry = get_session_registry(ua_sess);
5369 assert(registry);
5370
5371 if (ua_sess->buffer_type == LTTNG_BUFFER_PER_UID) {
5372 chan_reg_key = ua_chan->tracing_channel_id;
5373 } else {
5374 chan_reg_key = ua_chan->key;
5375 }
5376
5377 pthread_mutex_lock(&registry->lock);
5378
5379 /*
5380 * From this point on, this call acquires the ownership of the sig, fields
5381 * and model_emf_uri meaning any free are done inside it if needed. These
5382 * three variables MUST NOT be read/write after this.
5383 */
5384 ret_code = ust_registry_create_event(registry, chan_reg_key,
5385 sobjd, cobjd, name, sig, nr_fields, fields,
5386 loglevel_value, model_emf_uri, ua_sess->buffer_type,
5387 &event_id, app);
5388
5389 /*
5390 * The return value is returned to ustctl so in case of an error, the
5391 * application can be notified. In case of an error, it's important not to
5392 * return a negative error or else the application will get closed.
5393 */
5394 ret = ustctl_reply_register_event(sock, event_id, ret_code);
5395 if (ret < 0) {
5396 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5397 ERR("UST app reply event failed with ret %d", ret);
5398 } else {
5399 DBG3("UST app reply event failed. Application died");
5400 }
5401 /*
5402 * No need to wipe the create event since the application socket will
5403 * get close on error hence cleaning up everything by itself.
5404 */
5405 goto error;
5406 }
5407
5408 DBG3("UST registry event %s with id %" PRId32 " added successfully",
5409 name, event_id);
5410
5411 error:
5412 pthread_mutex_unlock(&registry->lock);
5413 error_rcu_unlock:
5414 rcu_read_unlock();
5415 return ret;
5416 }
5417
5418 /*
5419 * Add enum to the UST session registry. Once done, this replies to the
5420 * application with the appropriate error code.
5421 *
5422 * The session UST registry lock is acquired within this function.
5423 *
5424 * On success 0 is returned else a negative value.
5425 */
5426 static int add_enum_ust_registry(int sock, int sobjd, char *name,
5427 struct ustctl_enum_entry *entries, size_t nr_entries)
5428 {
5429 int ret = 0, ret_code;
5430 struct ust_app *app;
5431 struct ust_app_session *ua_sess;
5432 struct ust_registry_session *registry;
5433 uint64_t enum_id = -1ULL;
5434
5435 rcu_read_lock();
5436
5437 /* Lookup application. If not found, there is a code flow error. */
5438 app = find_app_by_notify_sock(sock);
5439 if (!app) {
5440 /* Return an error since this is not an error */
5441 DBG("Application socket %d is being torn down. Aborting enum registration",
5442 sock);
5443 free(entries);
5444 goto error_rcu_unlock;
5445 }
5446
5447 /* Lookup session by UST object descriptor. */
5448 ua_sess = find_session_by_objd(app, sobjd);
5449 if (!ua_sess) {
5450 /* Return an error since this is not an error */
5451 DBG("Application session is being torn down. Aborting enum registration.");
5452 free(entries);
5453 goto error_rcu_unlock;
5454 }
5455
5456 registry = get_session_registry(ua_sess);
5457 assert(registry);
5458
5459 pthread_mutex_lock(&registry->lock);
5460
5461 /*
5462 * From this point on, the callee acquires the ownership of
5463 * entries. The variable entries MUST NOT be read/written after
5464 * call.
5465 */
5466 ret_code = ust_registry_create_or_find_enum(registry, sobjd, name,
5467 entries, nr_entries, &enum_id);
5468 entries = NULL;
5469
5470 /*
5471 * The return value is returned to ustctl so in case of an error, the
5472 * application can be notified. In case of an error, it's important not to
5473 * return a negative error or else the application will get closed.
5474 */
5475 ret = ustctl_reply_register_enum(sock, enum_id, ret_code);
5476 if (ret < 0) {
5477 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5478 ERR("UST app reply enum failed with ret %d", ret);
5479 } else {
5480 DBG3("UST app reply enum failed. Application died");
5481 }
5482 /*
5483 * No need to wipe the create enum since the application socket will
5484 * get close on error hence cleaning up everything by itself.
5485 */
5486 goto error;
5487 }
5488
5489 DBG3("UST registry enum %s added successfully or already found", name);
5490
5491 error:
5492 pthread_mutex_unlock(&registry->lock);
5493 error_rcu_unlock:
5494 rcu_read_unlock();
5495 return ret;
5496 }
5497
5498 /*
5499 * Handle application notification through the given notify socket.
5500 *
5501 * Return 0 on success or else a negative value.
5502 */
5503 int ust_app_recv_notify(int sock)
5504 {
5505 int ret;
5506 enum ustctl_notify_cmd cmd;
5507
5508 DBG3("UST app receiving notify from sock %d", sock);
5509
5510 ret = ustctl_recv_notify(sock, &cmd);
5511 if (ret < 0) {
5512 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5513 ERR("UST app recv notify failed with ret %d", ret);
5514 } else {
5515 DBG3("UST app recv notify failed. Application died");
5516 }
5517 goto error;
5518 }
5519
5520 switch (cmd) {
5521 case USTCTL_NOTIFY_CMD_EVENT:
5522 {
5523 int sobjd, cobjd, loglevel_value;
5524 char name[LTTNG_UST_SYM_NAME_LEN], *sig, *model_emf_uri;
5525 size_t nr_fields;
5526 struct ustctl_field *fields;
5527
5528 DBG2("UST app ustctl register event received");
5529
5530 ret = ustctl_recv_register_event(sock, &sobjd, &cobjd, name,
5531 &loglevel_value, &sig, &nr_fields, &fields,
5532 &model_emf_uri);
5533 if (ret < 0) {
5534 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5535 ERR("UST app recv event failed with ret %d", ret);
5536 } else {
5537 DBG3("UST app recv event failed. Application died");
5538 }
5539 goto error;
5540 }
5541
5542 /*
5543 * Add event to the UST registry coming from the notify socket. This
5544 * call will free if needed the sig, fields and model_emf_uri. This
5545 * code path loses the ownsership of these variables and transfer them
5546 * to the this function.
5547 */
5548 ret = add_event_ust_registry(sock, sobjd, cobjd, name, sig, nr_fields,
5549 fields, loglevel_value, model_emf_uri);
5550 if (ret < 0) {
5551 goto error;
5552 }
5553
5554 break;
5555 }
5556 case USTCTL_NOTIFY_CMD_CHANNEL:
5557 {
5558 int sobjd, cobjd;
5559 size_t nr_fields;
5560 struct ustctl_field *fields;
5561
5562 DBG2("UST app ustctl register channel received");
5563
5564 ret = ustctl_recv_register_channel(sock, &sobjd, &cobjd, &nr_fields,
5565 &fields);
5566 if (ret < 0) {
5567 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5568 ERR("UST app recv channel failed with ret %d", ret);
5569 } else {
5570 DBG3("UST app recv channel failed. Application died");
5571 }
5572 goto error;
5573 }
5574
5575 /*
5576 * The fields ownership are transfered to this function call meaning
5577 * that if needed it will be freed. After this, it's invalid to access
5578 * fields or clean it up.
5579 */
5580 ret = reply_ust_register_channel(sock, sobjd, cobjd, nr_fields,
5581 fields);
5582 if (ret < 0) {
5583 goto error;
5584 }
5585
5586 break;
5587 }
5588 case USTCTL_NOTIFY_CMD_ENUM:
5589 {
5590 int sobjd;
5591 char name[LTTNG_UST_SYM_NAME_LEN];
5592 size_t nr_entries;
5593 struct ustctl_enum_entry *entries;
5594
5595 DBG2("UST app ustctl register enum received");
5596
5597 ret = ustctl_recv_register_enum(sock, &sobjd, name,
5598 &entries, &nr_entries);
5599 if (ret < 0) {
5600 if (ret != -EPIPE && ret != -LTTNG_UST_ERR_EXITING) {
5601 ERR("UST app recv enum failed with ret %d", ret);
5602 } else {
5603 DBG3("UST app recv enum failed. Application died");
5604 }
5605 goto error;
5606 }
5607
5608 /* Callee assumes ownership of entries */
5609 ret = add_enum_ust_registry(sock, sobjd, name,
5610 entries, nr_entries);
5611 if (ret < 0) {
5612 goto error;
5613 }
5614
5615 break;
5616 }
5617 default:
5618 /* Should NEVER happen. */
5619 assert(0);
5620 }
5621
5622 error:
5623 return ret;
5624 }
5625
5626 /*
5627 * Once the notify socket hangs up, this is called. First, it tries to find the
5628 * corresponding application. On failure, the call_rcu to close the socket is
5629 * executed. If an application is found, it tries to delete it from the notify
5630 * socket hash table. Whathever the result, it proceeds to the call_rcu.
5631 *
5632 * Note that an object needs to be allocated here so on ENOMEM failure, the
5633 * call RCU is not done but the rest of the cleanup is.
5634 */
5635 void ust_app_notify_sock_unregister(int sock)
5636 {
5637 int err_enomem = 0;
5638 struct lttng_ht_iter iter;
5639 struct ust_app *app;
5640 struct ust_app_notify_sock_obj *obj;
5641
5642 assert(sock >= 0);
5643
5644 rcu_read_lock();
5645
5646 obj = zmalloc(sizeof(*obj));
5647 if (!obj) {
5648 /*
5649 * An ENOMEM is kind of uncool. If this strikes we continue the
5650 * procedure but the call_rcu will not be called. In this case, we
5651 * accept the fd leak rather than possibly creating an unsynchronized
5652 * state between threads.
5653 *
5654 * TODO: The notify object should be created once the notify socket is
5655 * registered and stored independantely from the ust app object. The
5656 * tricky part is to synchronize the teardown of the application and
5657 * this notify object. Let's keep that in mind so we can avoid this
5658 * kind of shenanigans with ENOMEM in the teardown path.
5659 */
5660 err_enomem = 1;
5661 } else {
5662 obj->fd = sock;
5663 }
5664
5665 DBG("UST app notify socket unregister %d", sock);
5666
5667 /*
5668 * Lookup application by notify socket. If this fails, this means that the
5669 * hash table delete has already been done by the application
5670 * unregistration process so we can safely close the notify socket in a
5671 * call RCU.
5672 */
5673 app = find_app_by_notify_sock(sock);
5674 if (!app) {
5675 goto close_socket;
5676 }
5677
5678 iter.iter.node = &app->notify_sock_n.node;
5679
5680 /*
5681 * Whatever happens here either we fail or succeed, in both cases we have
5682 * to close the socket after a grace period to continue to the call RCU
5683 * here. If the deletion is successful, the application is not visible
5684 * anymore by other threads and is it fails it means that it was already
5685 * deleted from the hash table so either way we just have to close the
5686 * socket.
5687 */
5688 (void) lttng_ht_del(ust_app_ht_by_notify_sock, &iter);
5689
5690 close_socket:
5691 rcu_read_unlock();
5692
5693 /*
5694 * Close socket after a grace period to avoid for the socket to be reused
5695 * before the application object is freed creating potential race between
5696 * threads trying to add unique in the global hash table.
5697 */
5698 if (!err_enomem) {
5699 call_rcu(&obj->head, close_notify_sock_rcu);
5700 }
5701 }
5702
5703 /*
5704 * Destroy a ust app data structure and free its memory.
5705 */
5706 void ust_app_destroy(struct ust_app *app)
5707 {
5708 if (!app) {
5709 return;
5710 }
5711
5712 call_rcu(&app->pid_n.head, delete_ust_app_rcu);
5713 }
5714
5715 /*
5716 * Take a snapshot for a given UST session. The snapshot is sent to the given
5717 * output.
5718 *
5719 * Return 0 on success or else a negative value.
5720 */
5721 int ust_app_snapshot_record(struct ltt_ust_session *usess,
5722 struct snapshot_output *output, int wait,
5723 uint64_t nb_packets_per_stream)
5724 {
5725 int ret = 0;
5726 struct lttng_ht_iter iter;
5727 struct ust_app *app;
5728 char pathname[PATH_MAX];
5729
5730 assert(usess);
5731 assert(output);
5732
5733 rcu_read_lock();
5734
5735 switch (usess->buffer_type) {
5736 case LTTNG_BUFFER_PER_UID:
5737 {
5738 struct buffer_reg_uid *reg;
5739
5740 cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
5741 struct buffer_reg_channel *reg_chan;
5742 struct consumer_socket *socket;
5743
5744 /* Get consumer socket to use to push the metadata.*/
5745 socket = consumer_find_socket_by_bitness(reg->bits_per_long,
5746 usess->consumer);
5747 if (!socket) {
5748 ret = -EINVAL;
5749 goto error;
5750 }
5751
5752 memset(pathname, 0, sizeof(pathname));
5753 ret = snprintf(pathname, sizeof(pathname),
5754 DEFAULT_UST_TRACE_DIR "/" DEFAULT_UST_TRACE_UID_PATH,
5755 reg->uid, reg->bits_per_long);
5756 if (ret < 0) {
5757 PERROR("snprintf snapshot path");
5758 goto error;
5759 }
5760
5761 /* Add the UST default trace dir to path. */
5762 cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter,
5763 reg_chan, node.node) {
5764 ret = consumer_snapshot_channel(socket, reg_chan->consumer_key,
5765 output, 0, usess->uid, usess->gid, pathname, wait,
5766 nb_packets_per_stream);
5767 if (ret < 0) {
5768 goto error;
5769 }
5770 }
5771 ret = consumer_snapshot_channel(socket,
5772 reg->registry->reg.ust->metadata_key, output, 1,
5773 usess->uid, usess->gid, pathname, wait, 0);
5774 if (ret < 0) {
5775 goto error;
5776 }
5777 }
5778 break;
5779 }
5780 case LTTNG_BUFFER_PER_PID:
5781 {
5782 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
5783 struct consumer_socket *socket;
5784 struct lttng_ht_iter chan_iter;
5785 struct ust_app_channel *ua_chan;
5786 struct ust_app_session *ua_sess;
5787 struct ust_registry_session *registry;
5788
5789 ua_sess = lookup_session_by_app(usess, app);
5790 if (!ua_sess) {
5791 /* Session not associated with this app. */
5792 continue;
5793 }
5794
5795 /* Get the right consumer socket for the application. */
5796 socket = consumer_find_socket_by_bitness(app->bits_per_long,
5797 output->consumer);
5798 if (!socket) {
5799 ret = -EINVAL;
5800 goto error;
5801 }
5802
5803 /* Add the UST default trace dir to path. */
5804 memset(pathname, 0, sizeof(pathname));
5805 ret = snprintf(pathname, sizeof(pathname), DEFAULT_UST_TRACE_DIR "/%s",
5806 ua_sess->path);
5807 if (ret < 0) {
5808 PERROR("snprintf snapshot path");
5809 goto error;
5810 }
5811
5812 cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter,
5813 ua_chan, node.node) {
5814 ret = consumer_snapshot_channel(socket, ua_chan->key, output,
5815 0, ua_sess->euid, ua_sess->egid, pathname, wait,
5816 nb_packets_per_stream);
5817 if (ret < 0) {
5818 goto error;
5819 }
5820 }
5821
5822 registry = get_session_registry(ua_sess);
5823 assert(registry);
5824 ret = consumer_snapshot_channel(socket, registry->metadata_key, output,
5825 1, ua_sess->euid, ua_sess->egid, pathname, wait, 0);
5826 if (ret < 0) {
5827 goto error;
5828 }
5829 }
5830 break;
5831 }
5832 default:
5833 assert(0);
5834 break;
5835 }
5836
5837 error:
5838 rcu_read_unlock();
5839 return ret;
5840 }
5841
5842 /*
5843 * Return the size taken by one more packet per stream.
5844 */
5845 uint64_t ust_app_get_size_one_more_packet_per_stream(struct ltt_ust_session *usess,
5846 uint64_t cur_nr_packets)
5847 {
5848 uint64_t tot_size = 0;
5849 struct ust_app *app;
5850 struct lttng_ht_iter iter;
5851
5852 assert(usess);
5853
5854 switch (usess->buffer_type) {
5855 case LTTNG_BUFFER_PER_UID:
5856 {
5857 struct buffer_reg_uid *reg;
5858
5859 cds_list_for_each_entry(reg, &usess->buffer_reg_uid_list, lnode) {
5860 struct buffer_reg_channel *reg_chan;
5861
5862 rcu_read_lock();
5863 cds_lfht_for_each_entry(reg->registry->channels->ht, &iter.iter,
5864 reg_chan, node.node) {
5865 if (cur_nr_packets >= reg_chan->num_subbuf) {
5866 /*
5867 * Don't take channel into account if we
5868 * already grab all its packets.
5869 */
5870 continue;
5871 }
5872 tot_size += reg_chan->subbuf_size * reg_chan->stream_count;
5873 }
5874 rcu_read_unlock();
5875 }
5876 break;
5877 }
5878 case LTTNG_BUFFER_PER_PID:
5879 {
5880 rcu_read_lock();
5881 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
5882 struct ust_app_channel *ua_chan;
5883 struct ust_app_session *ua_sess;
5884 struct lttng_ht_iter chan_iter;
5885
5886 ua_sess = lookup_session_by_app(usess, app);
5887 if (!ua_sess) {
5888 /* Session not associated with this app. */
5889 continue;
5890 }
5891
5892 cds_lfht_for_each_entry(ua_sess->channels->ht, &chan_iter.iter,
5893 ua_chan, node.node) {
5894 if (cur_nr_packets >= ua_chan->attr.num_subbuf) {
5895 /*
5896 * Don't take channel into account if we
5897 * already grab all its packets.
5898 */
5899 continue;
5900 }
5901 tot_size += ua_chan->attr.subbuf_size * ua_chan->streams.count;
5902 }
5903 }
5904 rcu_read_unlock();
5905 break;
5906 }
5907 default:
5908 assert(0);
5909 break;
5910 }
5911
5912 return tot_size;
5913 }
5914
5915 int ust_app_uid_get_channel_runtime_stats(uint64_t ust_session_id,
5916 struct cds_list_head *buffer_reg_uid_list,
5917 struct consumer_output *consumer, uint64_t uchan_id,
5918 int overwrite, uint64_t *discarded, uint64_t *lost)
5919 {
5920 int ret;
5921 uint64_t consumer_chan_key;
5922
5923 ret = buffer_reg_uid_consumer_channel_key(
5924 buffer_reg_uid_list, ust_session_id,
5925 uchan_id, &consumer_chan_key);
5926 if (ret < 0) {
5927 goto end;
5928 }
5929
5930 if (overwrite) {
5931 ret = consumer_get_lost_packets(ust_session_id,
5932 consumer_chan_key, consumer, lost);
5933 *discarded = 0;
5934 } else {
5935 ret = consumer_get_discarded_events(ust_session_id,
5936 consumer_chan_key, consumer, discarded);
5937 *lost = 0;
5938 }
5939
5940 end:
5941 return ret;
5942 }
5943
5944 int ust_app_pid_get_channel_runtime_stats(struct ltt_ust_session *usess,
5945 struct ltt_ust_channel *uchan,
5946 struct consumer_output *consumer, int overwrite,
5947 uint64_t *discarded, uint64_t *lost)
5948 {
5949 int ret = 0;
5950 struct lttng_ht_iter iter;
5951 struct lttng_ht_node_str *ua_chan_node;
5952 struct ust_app *app;
5953 struct ust_app_session *ua_sess;
5954 struct ust_app_channel *ua_chan;
5955
5956 rcu_read_lock();
5957 /*
5958 * Iterate over every registered applications, return when we
5959 * found one in the right session and channel.
5960 */
5961 cds_lfht_for_each_entry(ust_app_ht->ht, &iter.iter, app, pid_n.node) {
5962 struct lttng_ht_iter uiter;
5963
5964 ua_sess = lookup_session_by_app(usess, app);
5965 if (ua_sess == NULL) {
5966 continue;
5967 }
5968
5969 /* Get channel */
5970 lttng_ht_lookup(ua_sess->channels, (void *) uchan->name, &uiter);
5971 ua_chan_node = lttng_ht_iter_get_node_str(&uiter);
5972 /* If the session is found for the app, the channel must be there */
5973 assert(ua_chan_node);
5974
5975 ua_chan = caa_container_of(ua_chan_node, struct ust_app_channel, node);
5976
5977 if (overwrite) {
5978 ret = consumer_get_lost_packets(usess->id, ua_chan->key,
5979 consumer, lost);
5980 *discarded = 0;
5981 goto end;
5982 } else {
5983 ret = consumer_get_discarded_events(usess->id,
5984 ua_chan->key, consumer, discarded);
5985 *lost = 0;
5986 goto end;
5987 }
5988 }
5989
5990 end:
5991 rcu_read_unlock();
5992 return ret;
5993 }
This page took 0.167083 seconds and 3 git commands to generate.