2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License, version 2 only,
6 * as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
13 * You should have received a copy of the GNU General Public License along
14 * with this program; if not, write to the Free Software Foundation, Inc.,
15 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
26 #include <sys/types.h>
28 #include <urcu/compiler.h>
29 #include <lttng/ust-error.h>
32 #include <common/common.h>
33 #include <common/sessiond-comm/sessiond-comm.h>
35 #include "buffer-registry.h"
39 #include "ust-consumer.h"
42 /* Next available channel key. */
43 static unsigned long next_channel_key
;
44 static unsigned long next_session_id
;
47 * Return the atomically incremented value of next_channel_key.
49 static inline unsigned long get_next_channel_key(void)
51 return uatomic_add_return(&next_channel_key
, 1);
55 * Return the atomically incremented value of next_session_id.
57 static inline unsigned long get_next_session_id(void)
59 return uatomic_add_return(&next_session_id
, 1);
62 static void copy_channel_attr_to_ustctl(
63 struct ustctl_consumer_channel_attr
*attr
,
64 struct lttng_ust_channel_attr
*uattr
)
66 /* Copy event attributes since the layout is different. */
67 attr
->subbuf_size
= uattr
->subbuf_size
;
68 attr
->num_subbuf
= uattr
->num_subbuf
;
69 attr
->overwrite
= uattr
->overwrite
;
70 attr
->switch_timer_interval
= uattr
->switch_timer_interval
;
71 attr
->read_timer_interval
= uattr
->read_timer_interval
;
72 attr
->output
= uattr
->output
;
76 * Match function for the hash table lookup.
78 * It matches an ust app event based on three attributes which are the event
79 * name, the filter bytecode and the loglevel.
81 static int ht_match_ust_app_event(struct cds_lfht_node
*node
, const void *_key
)
83 struct ust_app_event
*event
;
84 const struct ust_app_ht_key
*key
;
89 event
= caa_container_of(node
, struct ust_app_event
, node
.node
);
92 /* Match the 3 elements of the key: name, filter and loglevel. */
95 if (strncmp(event
->attr
.name
, key
->name
, sizeof(event
->attr
.name
)) != 0) {
100 if (event
->attr
.loglevel
!= key
->loglevel
) {
101 if (event
->attr
.loglevel_type
== LTTNG_UST_LOGLEVEL_ALL
102 && key
->loglevel
== 0 && event
->attr
.loglevel
== -1) {
104 * Match is accepted. This is because on event creation, the
105 * loglevel is set to -1 if the event loglevel type is ALL so 0 and
106 * -1 are accepted for this loglevel type since 0 is the one set by
107 * the API when receiving an enable event.
114 /* One of the filters is NULL, fail. */
115 if ((key
->filter
&& !event
->filter
) || (!key
->filter
&& event
->filter
)) {
119 if (key
->filter
&& event
->filter
) {
120 /* Both filters exists, check length followed by the bytecode. */
121 if (event
->filter
->len
!= key
->filter
->len
||
122 memcmp(event
->filter
->data
, key
->filter
->data
,
123 event
->filter
->len
) != 0) {
136 * Unique add of an ust app event in the given ht. This uses the custom
137 * ht_match_ust_app_event match function and the event name as hash.
139 static void add_unique_ust_app_event(struct ust_app_channel
*ua_chan
,
140 struct ust_app_event
*event
)
142 struct cds_lfht_node
*node_ptr
;
143 struct ust_app_ht_key key
;
147 assert(ua_chan
->events
);
150 ht
= ua_chan
->events
;
151 key
.name
= event
->attr
.name
;
152 key
.filter
= event
->filter
;
153 key
.loglevel
= event
->attr
.loglevel
;
155 node_ptr
= cds_lfht_add_unique(ht
->ht
,
156 ht
->hash_fct(event
->node
.key
, lttng_ht_seed
),
157 ht_match_ust_app_event
, &key
, &event
->node
.node
);
158 assert(node_ptr
== &event
->node
.node
);
162 * Close the notify socket from the given RCU head object. This MUST be called
163 * through a call_rcu().
165 static void close_notify_sock_rcu(struct rcu_head
*head
)
168 struct ust_app_notify_sock_obj
*obj
=
169 caa_container_of(head
, struct ust_app_notify_sock_obj
, head
);
171 /* Must have a valid fd here. */
172 assert(obj
->fd
>= 0);
174 ret
= close(obj
->fd
);
176 ERR("close notify sock %d RCU", obj
->fd
);
178 lttng_fd_put(LTTNG_FD_APPS
, 1);
184 * Return the session registry according to the buffer type of the given
187 * A registry per UID object MUST exists before calling this function or else
188 * it assert() if not found. RCU read side lock must be acquired.
190 static struct ust_registry_session
*get_session_registry(
191 struct ust_app_session
*ua_sess
)
193 struct ust_registry_session
*registry
= NULL
;
197 switch (ua_sess
->buffer_type
) {
198 case LTTNG_BUFFER_PER_PID
:
200 struct buffer_reg_pid
*reg_pid
= buffer_reg_pid_find(ua_sess
->id
);
204 registry
= reg_pid
->registry
->reg
.ust
;
207 case LTTNG_BUFFER_PER_UID
:
209 struct buffer_reg_uid
*reg_uid
= buffer_reg_uid_find(
210 ua_sess
->tracing_id
, ua_sess
->bits_per_long
, ua_sess
->uid
);
214 registry
= reg_uid
->registry
->reg
.ust
;
226 * Delete ust context safely. RCU read lock must be held before calling
230 void delete_ust_app_ctx(int sock
, struct ust_app_ctx
*ua_ctx
)
237 ret
= ustctl_release_object(sock
, ua_ctx
->obj
);
238 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
239 ERR("UST app sock %d release ctx obj handle %d failed with ret %d",
240 sock
, ua_ctx
->obj
->handle
, ret
);
248 * Delete ust app event safely. RCU read lock must be held before calling
252 void delete_ust_app_event(int sock
, struct ust_app_event
*ua_event
)
258 free(ua_event
->filter
);
260 if (ua_event
->obj
!= NULL
) {
261 ret
= ustctl_release_object(sock
, ua_event
->obj
);
262 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
263 ERR("UST app sock %d release event obj failed with ret %d",
272 * Release ust data object of the given stream.
274 * Return 0 on success or else a negative value.
276 static int release_ust_app_stream(int sock
, struct ust_app_stream
*stream
)
283 ret
= ustctl_release_object(sock
, stream
->obj
);
284 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
285 ERR("UST app sock %d release stream obj failed with ret %d",
288 lttng_fd_put(LTTNG_FD_APPS
, 2);
296 * Delete ust app stream safely. RCU read lock must be held before calling
300 void delete_ust_app_stream(int sock
, struct ust_app_stream
*stream
)
304 (void) release_ust_app_stream(sock
, stream
);
309 * We need to execute ht_destroy outside of RCU read-side critical
310 * section, so we postpone its execution using call_rcu. It is simpler
311 * than to change the semantic of the many callers of
312 * delete_ust_app_channel().
315 void delete_ust_app_channel_rcu(struct rcu_head
*head
)
317 struct ust_app_channel
*ua_chan
=
318 caa_container_of(head
, struct ust_app_channel
, rcu_head
);
320 lttng_ht_destroy(ua_chan
->ctx
);
321 lttng_ht_destroy(ua_chan
->events
);
326 * Delete ust app channel safely. RCU read lock must be held before calling
330 void delete_ust_app_channel(int sock
, struct ust_app_channel
*ua_chan
,
334 struct lttng_ht_iter iter
;
335 struct ust_app_event
*ua_event
;
336 struct ust_app_ctx
*ua_ctx
;
337 struct ust_app_stream
*stream
, *stmp
;
338 struct ust_registry_session
*registry
;
342 DBG3("UST app deleting channel %s", ua_chan
->name
);
345 cds_list_for_each_entry_safe(stream
, stmp
, &ua_chan
->streams
.head
, list
) {
346 cds_list_del(&stream
->list
);
347 delete_ust_app_stream(sock
, stream
);
351 cds_lfht_for_each_entry(ua_chan
->ctx
->ht
, &iter
.iter
, ua_ctx
, node
.node
) {
352 ret
= lttng_ht_del(ua_chan
->ctx
, &iter
);
354 delete_ust_app_ctx(sock
, ua_ctx
);
358 cds_lfht_for_each_entry(ua_chan
->events
->ht
, &iter
.iter
, ua_event
,
360 ret
= lttng_ht_del(ua_chan
->events
, &iter
);
362 delete_ust_app_event(sock
, ua_event
);
365 /* Wipe and free registry from session registry. */
366 registry
= get_session_registry(ua_chan
->session
);
368 ust_registry_channel_del_free(registry
, ua_chan
->key
);
371 if (ua_chan
->obj
!= NULL
) {
372 /* Remove channel from application UST object descriptor. */
373 iter
.iter
.node
= &ua_chan
->ust_objd_node
.node
;
374 lttng_ht_del(app
->ust_objd
, &iter
);
375 ret
= ustctl_release_object(sock
, ua_chan
->obj
);
376 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
377 ERR("UST app sock %d release channel obj failed with ret %d",
380 lttng_fd_put(LTTNG_FD_APPS
, 1);
383 call_rcu(&ua_chan
->rcu_head
, delete_ust_app_channel_rcu
);
387 * Push metadata to consumer socket. The socket lock MUST be acquired.
389 * On success, return the len of metadata pushed or else a negative value.
391 ssize_t
ust_app_push_metadata(struct ust_registry_session
*registry
,
392 struct consumer_socket
*socket
, int send_zero_data
)
395 char *metadata_str
= NULL
;
401 /* Should never be 0 which is the initial state. */
402 assert(registry
->metadata_key
);
404 pthread_mutex_lock(®istry
->lock
);
406 offset
= registry
->metadata_len_sent
;
407 len
= registry
->metadata_len
- registry
->metadata_len_sent
;
409 DBG3("No metadata to push for metadata key %" PRIu64
,
410 registry
->metadata_key
);
412 if (send_zero_data
) {
413 DBG("No metadata to push");
419 /* Allocate only what we have to send. */
420 metadata_str
= zmalloc(len
);
422 PERROR("zmalloc ust app metadata string");
426 /* Copy what we haven't send out. */
427 memcpy(metadata_str
, registry
->metadata
+ offset
, len
);
428 registry
->metadata_len_sent
+= len
;
431 pthread_mutex_unlock(®istry
->lock
);
432 ret
= consumer_push_metadata(socket
, registry
->metadata_key
,
433 metadata_str
, len
, offset
);
444 pthread_mutex_unlock(®istry
->lock
);
451 * For a given application and session, push metadata to consumer. The session
452 * lock MUST be acquired here before calling this.
453 * Either sock or consumer is required : if sock is NULL, the default
454 * socket to send the metadata is retrieved from consumer, if sock
455 * is not NULL we use it to send the metadata.
457 * Return 0 on success else a negative error.
459 static int push_metadata(struct ust_registry_session
*registry
,
460 struct consumer_output
*consumer
)
464 struct consumer_socket
*socket
;
472 * Means that no metadata was assigned to the session. This can happens if
473 * no start has been done previously.
475 if (!registry
->metadata_key
) {
477 goto error_rcu_unlock
;
480 /* Get consumer socket to use to push the metadata.*/
481 socket
= consumer_find_socket_by_bitness(registry
->bits_per_long
,
485 goto error_rcu_unlock
;
489 * TODO: Currently, we hold the socket lock around sampling of the next
490 * metadata segment to ensure we send metadata over the consumer socket in
491 * the correct order. This makes the registry lock nest inside the socket
494 * Please note that this is a temporary measure: we should move this lock
495 * back into ust_consumer_push_metadata() when the consumer gets the
496 * ability to reorder the metadata it receives.
498 pthread_mutex_lock(socket
->lock
);
499 ret
= ust_app_push_metadata(registry
, socket
, 0);
500 pthread_mutex_unlock(socket
->lock
);
503 goto error_rcu_unlock
;
515 * Send to the consumer a close metadata command for the given session. Once
516 * done, the metadata channel is deleted and the session metadata pointer is
517 * nullified. The session lock MUST be acquired here unless the application is
518 * in the destroy path.
520 * Return 0 on success else a negative value.
522 static int close_metadata(struct ust_registry_session
*registry
,
523 struct consumer_output
*consumer
)
526 struct consumer_socket
*socket
;
533 if (!registry
->metadata_key
|| registry
->metadata_closed
) {
538 /* Get consumer socket to use to push the metadata.*/
539 socket
= consumer_find_socket_by_bitness(registry
->bits_per_long
,
546 ret
= consumer_close_metadata(socket
, registry
->metadata_key
);
551 /* Metadata successfully closed. Flag the registry. */
552 registry
->metadata_closed
= 1;
560 * We need to execute ht_destroy outside of RCU read-side critical
561 * section, so we postpone its execution using call_rcu. It is simpler
562 * than to change the semantic of the many callers of
563 * delete_ust_app_session().
566 void delete_ust_app_session_rcu(struct rcu_head
*head
)
568 struct ust_app_session
*ua_sess
=
569 caa_container_of(head
, struct ust_app_session
, rcu_head
);
571 lttng_ht_destroy(ua_sess
->channels
);
576 * Delete ust app session safely. RCU read lock must be held before calling
580 void delete_ust_app_session(int sock
, struct ust_app_session
*ua_sess
,
584 struct lttng_ht_iter iter
;
585 struct ust_app_channel
*ua_chan
;
586 struct ust_registry_session
*registry
;
590 registry
= get_session_registry(ua_sess
);
592 /* Push metadata for application before freeing the application. */
593 (void) push_metadata(registry
, ua_sess
->consumer
);
596 * Don't ask to close metadata for global per UID buffers. Close
597 * metadata only on destroy trace session in this case.
599 if (ua_sess
->buffer_type
!= LTTNG_BUFFER_PER_UID
) {
600 /* And ask to close it for this session registry. */
601 (void) close_metadata(registry
, ua_sess
->consumer
);
605 cds_lfht_for_each_entry(ua_sess
->channels
->ht
, &iter
.iter
, ua_chan
,
607 ret
= lttng_ht_del(ua_sess
->channels
, &iter
);
609 delete_ust_app_channel(sock
, ua_chan
, app
);
612 /* In case of per PID, the registry is kept in the session. */
613 if (ua_sess
->buffer_type
== LTTNG_BUFFER_PER_PID
) {
614 struct buffer_reg_pid
*reg_pid
= buffer_reg_pid_find(ua_sess
->id
);
616 buffer_reg_pid_remove(reg_pid
);
617 buffer_reg_pid_destroy(reg_pid
);
621 if (ua_sess
->handle
!= -1) {
622 ret
= ustctl_release_handle(sock
, ua_sess
->handle
);
623 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
624 ERR("UST app sock %d release session handle failed with ret %d",
628 call_rcu(&ua_sess
->rcu_head
, delete_ust_app_session_rcu
);
632 * Delete a traceable application structure from the global list. Never call
633 * this function outside of a call_rcu call.
635 * RCU read side lock should _NOT_ be held when calling this function.
638 void delete_ust_app(struct ust_app
*app
)
641 struct ust_app_session
*ua_sess
, *tmp_ua_sess
;
643 /* Delete ust app sessions info */
648 cds_list_for_each_entry_safe(ua_sess
, tmp_ua_sess
, &app
->teardown_head
,
650 /* Free every object in the session and the session. */
652 delete_ust_app_session(sock
, ua_sess
, app
);
656 lttng_ht_destroy(app
->sessions
);
657 lttng_ht_destroy(app
->ust_objd
);
660 * Wait until we have deleted the application from the sock hash table
661 * before closing this socket, otherwise an application could re-use the
662 * socket ID and race with the teardown, using the same hash table entry.
664 * It's OK to leave the close in call_rcu. We want it to stay unique for
665 * all RCU readers that could run concurrently with unregister app,
666 * therefore we _need_ to only close that socket after a grace period. So
667 * it should stay in this RCU callback.
669 * This close() is a very important step of the synchronization model so
670 * every modification to this function must be carefully reviewed.
676 lttng_fd_put(LTTNG_FD_APPS
, 1);
678 DBG2("UST app pid %d deleted", app
->pid
);
683 * URCU intermediate call to delete an UST app.
686 void delete_ust_app_rcu(struct rcu_head
*head
)
688 struct lttng_ht_node_ulong
*node
=
689 caa_container_of(head
, struct lttng_ht_node_ulong
, head
);
690 struct ust_app
*app
=
691 caa_container_of(node
, struct ust_app
, pid_n
);
693 DBG3("Call RCU deleting app PID %d", app
->pid
);
698 * Delete the session from the application ht and delete the data structure by
699 * freeing every object inside and releasing them.
701 static void destroy_app_session(struct ust_app
*app
,
702 struct ust_app_session
*ua_sess
)
705 struct lttng_ht_iter iter
;
710 iter
.iter
.node
= &ua_sess
->node
.node
;
711 ret
= lttng_ht_del(app
->sessions
, &iter
);
713 /* Already scheduled for teardown. */
717 /* Once deleted, free the data structure. */
718 delete_ust_app_session(app
->sock
, ua_sess
, app
);
725 * Alloc new UST app session.
728 struct ust_app_session
*alloc_ust_app_session(struct ust_app
*app
)
730 struct ust_app_session
*ua_sess
;
732 /* Init most of the default value by allocating and zeroing */
733 ua_sess
= zmalloc(sizeof(struct ust_app_session
));
734 if (ua_sess
== NULL
) {
739 ua_sess
->handle
= -1;
740 ua_sess
->channels
= lttng_ht_new(0, LTTNG_HT_TYPE_STRING
);
741 pthread_mutex_init(&ua_sess
->lock
, NULL
);
750 * Alloc new UST app channel.
753 struct ust_app_channel
*alloc_ust_app_channel(char *name
,
754 struct ust_app_session
*ua_sess
,
755 struct lttng_ust_channel_attr
*attr
)
757 struct ust_app_channel
*ua_chan
;
759 /* Init most of the default value by allocating and zeroing */
760 ua_chan
= zmalloc(sizeof(struct ust_app_channel
));
761 if (ua_chan
== NULL
) {
766 /* Setup channel name */
767 strncpy(ua_chan
->name
, name
, sizeof(ua_chan
->name
));
768 ua_chan
->name
[sizeof(ua_chan
->name
) - 1] = '\0';
770 ua_chan
->enabled
= 1;
771 ua_chan
->handle
= -1;
772 ua_chan
->session
= ua_sess
;
773 ua_chan
->key
= get_next_channel_key();
774 ua_chan
->ctx
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
775 ua_chan
->events
= lttng_ht_new(0, LTTNG_HT_TYPE_STRING
);
776 lttng_ht_node_init_str(&ua_chan
->node
, ua_chan
->name
);
778 CDS_INIT_LIST_HEAD(&ua_chan
->streams
.head
);
780 /* Copy attributes */
782 /* Translate from lttng_ust_channel to ustctl_consumer_channel_attr. */
783 ua_chan
->attr
.subbuf_size
= attr
->subbuf_size
;
784 ua_chan
->attr
.num_subbuf
= attr
->num_subbuf
;
785 ua_chan
->attr
.overwrite
= attr
->overwrite
;
786 ua_chan
->attr
.switch_timer_interval
= attr
->switch_timer_interval
;
787 ua_chan
->attr
.read_timer_interval
= attr
->read_timer_interval
;
788 ua_chan
->attr
.output
= attr
->output
;
790 /* By default, the channel is a per cpu channel. */
791 ua_chan
->attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
793 DBG3("UST app channel %s allocated", ua_chan
->name
);
802 * Allocate and initialize a UST app stream.
804 * Return newly allocated stream pointer or NULL on error.
806 struct ust_app_stream
*ust_app_alloc_stream(void)
808 struct ust_app_stream
*stream
= NULL
;
810 stream
= zmalloc(sizeof(*stream
));
811 if (stream
== NULL
) {
812 PERROR("zmalloc ust app stream");
816 /* Zero could be a valid value for a handle so flag it to -1. */
824 * Alloc new UST app event.
827 struct ust_app_event
*alloc_ust_app_event(char *name
,
828 struct lttng_ust_event
*attr
)
830 struct ust_app_event
*ua_event
;
832 /* Init most of the default value by allocating and zeroing */
833 ua_event
= zmalloc(sizeof(struct ust_app_event
));
834 if (ua_event
== NULL
) {
839 ua_event
->enabled
= 1;
840 strncpy(ua_event
->name
, name
, sizeof(ua_event
->name
));
841 ua_event
->name
[sizeof(ua_event
->name
) - 1] = '\0';
842 lttng_ht_node_init_str(&ua_event
->node
, ua_event
->name
);
844 /* Copy attributes */
846 memcpy(&ua_event
->attr
, attr
, sizeof(ua_event
->attr
));
849 DBG3("UST app event %s allocated", ua_event
->name
);
858 * Alloc new UST app context.
861 struct ust_app_ctx
*alloc_ust_app_ctx(struct lttng_ust_context
*uctx
)
863 struct ust_app_ctx
*ua_ctx
;
865 ua_ctx
= zmalloc(sizeof(struct ust_app_ctx
));
866 if (ua_ctx
== NULL
) {
871 memcpy(&ua_ctx
->ctx
, uctx
, sizeof(ua_ctx
->ctx
));
874 DBG3("UST app context %d allocated", ua_ctx
->ctx
.ctx
);
881 * Allocate a filter and copy the given original filter.
883 * Return allocated filter or NULL on error.
885 static struct lttng_ust_filter_bytecode
*alloc_copy_ust_app_filter(
886 struct lttng_ust_filter_bytecode
*orig_f
)
888 struct lttng_ust_filter_bytecode
*filter
= NULL
;
890 /* Copy filter bytecode */
891 filter
= zmalloc(sizeof(*filter
) + orig_f
->len
);
893 PERROR("zmalloc alloc ust app filter");
897 memcpy(filter
, orig_f
, sizeof(*filter
) + orig_f
->len
);
904 * Find an ust_app using the sock and return it. RCU read side lock must be
905 * held before calling this helper function.
908 struct ust_app
*find_app_by_sock(int sock
)
910 struct lttng_ht_node_ulong
*node
;
911 struct lttng_ht_iter iter
;
913 lttng_ht_lookup(ust_app_ht_by_sock
, (void *)((unsigned long) sock
), &iter
);
914 node
= lttng_ht_iter_get_node_ulong(&iter
);
916 DBG2("UST app find by sock %d not found", sock
);
920 return caa_container_of(node
, struct ust_app
, sock_n
);
927 * Find an ust_app using the notify sock and return it. RCU read side lock must
928 * be held before calling this helper function.
930 static struct ust_app
*find_app_by_notify_sock(int sock
)
932 struct lttng_ht_node_ulong
*node
;
933 struct lttng_ht_iter iter
;
935 lttng_ht_lookup(ust_app_ht_by_notify_sock
, (void *)((unsigned long) sock
),
937 node
= lttng_ht_iter_get_node_ulong(&iter
);
939 DBG2("UST app find by notify sock %d not found", sock
);
943 return caa_container_of(node
, struct ust_app
, notify_sock_n
);
950 * Lookup for an ust app event based on event name, filter bytecode and the
953 * Return an ust_app_event object or NULL on error.
955 static struct ust_app_event
*find_ust_app_event(struct lttng_ht
*ht
,
956 char *name
, struct lttng_ust_filter_bytecode
*filter
, int loglevel
)
958 struct lttng_ht_iter iter
;
959 struct lttng_ht_node_str
*node
;
960 struct ust_app_event
*event
= NULL
;
961 struct ust_app_ht_key key
;
966 /* Setup key for event lookup. */
969 key
.loglevel
= loglevel
;
971 /* Lookup using the event name as hash and a custom match fct. */
972 cds_lfht_lookup(ht
->ht
, ht
->hash_fct((void *) name
, lttng_ht_seed
),
973 ht_match_ust_app_event
, &key
, &iter
.iter
);
974 node
= lttng_ht_iter_get_node_str(&iter
);
979 event
= caa_container_of(node
, struct ust_app_event
, node
);
986 * Create the channel context on the tracer.
988 * Called with UST app session lock held.
991 int create_ust_channel_context(struct ust_app_channel
*ua_chan
,
992 struct ust_app_ctx
*ua_ctx
, struct ust_app
*app
)
996 health_code_update();
998 ret
= ustctl_add_context(app
->sock
, &ua_ctx
->ctx
,
999 ua_chan
->obj
, &ua_ctx
->obj
);
1001 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1002 ERR("UST app create channel context failed for app (pid: %d) "
1003 "with ret %d", app
->pid
, ret
);
1005 DBG3("UST app disable event failed. Application is dead.");
1010 ua_ctx
->handle
= ua_ctx
->obj
->handle
;
1012 DBG2("UST app context handle %d created successfully for channel %s",
1013 ua_ctx
->handle
, ua_chan
->name
);
1016 health_code_update();
1021 * Set the filter on the tracer.
1024 int set_ust_event_filter(struct ust_app_event
*ua_event
,
1025 struct ust_app
*app
)
1029 health_code_update();
1031 if (!ua_event
->filter
) {
1036 ret
= ustctl_set_filter(app
->sock
, ua_event
->filter
,
1039 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1040 ERR("UST app event %s filter failed for app (pid: %d) "
1041 "with ret %d", ua_event
->attr
.name
, app
->pid
, ret
);
1043 DBG3("UST app filter event failed. Application is dead.");
1048 DBG2("UST filter set successfully for event %s", ua_event
->name
);
1051 health_code_update();
1056 * Disable the specified event on to UST tracer for the UST session.
1058 static int disable_ust_event(struct ust_app
*app
,
1059 struct ust_app_session
*ua_sess
, struct ust_app_event
*ua_event
)
1063 health_code_update();
1065 ret
= ustctl_disable(app
->sock
, ua_event
->obj
);
1067 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1068 ERR("UST app event %s disable failed for app (pid: %d) "
1069 "and session handle %d with ret %d",
1070 ua_event
->attr
.name
, app
->pid
, ua_sess
->handle
, ret
);
1072 DBG3("UST app disable event failed. Application is dead.");
1077 DBG2("UST app event %s disabled successfully for app (pid: %d)",
1078 ua_event
->attr
.name
, app
->pid
);
1081 health_code_update();
1086 * Disable the specified channel on to UST tracer for the UST session.
1088 static int disable_ust_channel(struct ust_app
*app
,
1089 struct ust_app_session
*ua_sess
, struct ust_app_channel
*ua_chan
)
1093 health_code_update();
1095 ret
= ustctl_disable(app
->sock
, ua_chan
->obj
);
1097 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1098 ERR("UST app channel %s disable failed for app (pid: %d) "
1099 "and session handle %d with ret %d",
1100 ua_chan
->name
, app
->pid
, ua_sess
->handle
, ret
);
1102 DBG3("UST app disable channel failed. Application is dead.");
1107 DBG2("UST app channel %s disabled successfully for app (pid: %d)",
1108 ua_chan
->name
, app
->pid
);
1111 health_code_update();
1116 * Enable the specified channel on to UST tracer for the UST session.
1118 static int enable_ust_channel(struct ust_app
*app
,
1119 struct ust_app_session
*ua_sess
, struct ust_app_channel
*ua_chan
)
1123 health_code_update();
1125 ret
= ustctl_enable(app
->sock
, ua_chan
->obj
);
1127 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1128 ERR("UST app channel %s enable failed for app (pid: %d) "
1129 "and session handle %d with ret %d",
1130 ua_chan
->name
, app
->pid
, ua_sess
->handle
, ret
);
1132 DBG3("UST app enable channel failed. Application is dead.");
1137 ua_chan
->enabled
= 1;
1139 DBG2("UST app channel %s enabled successfully for app (pid: %d)",
1140 ua_chan
->name
, app
->pid
);
1143 health_code_update();
1148 * Enable the specified event on to UST tracer for the UST session.
1150 static int enable_ust_event(struct ust_app
*app
,
1151 struct ust_app_session
*ua_sess
, struct ust_app_event
*ua_event
)
1155 health_code_update();
1157 ret
= ustctl_enable(app
->sock
, ua_event
->obj
);
1159 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1160 ERR("UST app event %s enable failed for app (pid: %d) "
1161 "and session handle %d with ret %d",
1162 ua_event
->attr
.name
, app
->pid
, ua_sess
->handle
, ret
);
1164 DBG3("UST app enable event failed. Application is dead.");
1169 DBG2("UST app event %s enabled successfully for app (pid: %d)",
1170 ua_event
->attr
.name
, app
->pid
);
1173 health_code_update();
1178 * Send channel and stream buffer to application.
1180 * Return 0 on success. On error, a negative value is returned.
1182 static int send_channel_pid_to_ust(struct ust_app
*app
,
1183 struct ust_app_session
*ua_sess
, struct ust_app_channel
*ua_chan
)
1186 struct ust_app_stream
*stream
, *stmp
;
1192 health_code_update();
1194 DBG("UST app sending channel %s to UST app sock %d", ua_chan
->name
,
1197 /* Send channel to the application. */
1198 ret
= ust_consumer_send_channel_to_ust(app
, ua_sess
, ua_chan
);
1203 health_code_update();
1205 /* Send all streams to application. */
1206 cds_list_for_each_entry_safe(stream
, stmp
, &ua_chan
->streams
.head
, list
) {
1207 ret
= ust_consumer_send_stream_to_ust(app
, ua_chan
, stream
);
1211 /* We don't need the stream anymore once sent to the tracer. */
1212 cds_list_del(&stream
->list
);
1213 delete_ust_app_stream(-1, stream
);
1215 /* Flag the channel that it is sent to the application. */
1216 ua_chan
->is_sent
= 1;
1219 health_code_update();
1224 * Create the specified event onto the UST tracer for a UST session.
1226 * Should be called with session mutex held.
1229 int create_ust_event(struct ust_app
*app
, struct ust_app_session
*ua_sess
,
1230 struct ust_app_channel
*ua_chan
, struct ust_app_event
*ua_event
)
1234 health_code_update();
1236 /* Create UST event on tracer */
1237 ret
= ustctl_create_event(app
->sock
, &ua_event
->attr
, ua_chan
->obj
,
1240 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1241 ERR("Error ustctl create event %s for app pid: %d with ret %d",
1242 ua_event
->attr
.name
, app
->pid
, ret
);
1244 DBG3("UST app create event failed. Application is dead.");
1249 ua_event
->handle
= ua_event
->obj
->handle
;
1251 DBG2("UST app event %s created successfully for pid:%d",
1252 ua_event
->attr
.name
, app
->pid
);
1254 health_code_update();
1256 /* Set filter if one is present. */
1257 if (ua_event
->filter
) {
1258 ret
= set_ust_event_filter(ua_event
, app
);
1264 /* If event not enabled, disable it on the tracer */
1265 if (ua_event
->enabled
== 0) {
1266 ret
= disable_ust_event(app
, ua_sess
, ua_event
);
1269 * If we hit an EPERM, something is wrong with our disable call. If
1270 * we get an EEXIST, there is a problem on the tracer side since we
1274 case -LTTNG_UST_ERR_PERM
:
1275 /* Code flow problem */
1277 case -LTTNG_UST_ERR_EXIST
:
1278 /* It's OK for our use case. */
1289 health_code_update();
1294 * Copy data between an UST app event and a LTT event.
1296 static void shadow_copy_event(struct ust_app_event
*ua_event
,
1297 struct ltt_ust_event
*uevent
)
1299 strncpy(ua_event
->name
, uevent
->attr
.name
, sizeof(ua_event
->name
));
1300 ua_event
->name
[sizeof(ua_event
->name
) - 1] = '\0';
1302 ua_event
->enabled
= uevent
->enabled
;
1304 /* Copy event attributes */
1305 memcpy(&ua_event
->attr
, &uevent
->attr
, sizeof(ua_event
->attr
));
1307 /* Copy filter bytecode */
1308 if (uevent
->filter
) {
1309 ua_event
->filter
= alloc_copy_ust_app_filter(uevent
->filter
);
1310 /* Filter might be NULL here in case of ENONEM. */
1315 * Copy data between an UST app channel and a LTT channel.
1317 static void shadow_copy_channel(struct ust_app_channel
*ua_chan
,
1318 struct ltt_ust_channel
*uchan
)
1320 struct lttng_ht_iter iter
;
1321 struct ltt_ust_event
*uevent
;
1322 struct ltt_ust_context
*uctx
;
1323 struct ust_app_event
*ua_event
;
1324 struct ust_app_ctx
*ua_ctx
;
1326 DBG2("UST app shadow copy of channel %s started", ua_chan
->name
);
1328 strncpy(ua_chan
->name
, uchan
->name
, sizeof(ua_chan
->name
));
1329 ua_chan
->name
[sizeof(ua_chan
->name
) - 1] = '\0';
1331 ua_chan
->tracefile_size
= uchan
->tracefile_size
;
1332 ua_chan
->tracefile_count
= uchan
->tracefile_count
;
1334 /* Copy event attributes since the layout is different. */
1335 ua_chan
->attr
.subbuf_size
= uchan
->attr
.subbuf_size
;
1336 ua_chan
->attr
.num_subbuf
= uchan
->attr
.num_subbuf
;
1337 ua_chan
->attr
.overwrite
= uchan
->attr
.overwrite
;
1338 ua_chan
->attr
.switch_timer_interval
= uchan
->attr
.switch_timer_interval
;
1339 ua_chan
->attr
.read_timer_interval
= uchan
->attr
.read_timer_interval
;
1340 ua_chan
->attr
.output
= uchan
->attr
.output
;
1342 * Note that the attribute channel type is not set since the channel on the
1343 * tracing registry side does not have this information.
1346 ua_chan
->enabled
= uchan
->enabled
;
1347 ua_chan
->tracing_channel_id
= uchan
->id
;
1349 cds_lfht_for_each_entry(uchan
->ctx
->ht
, &iter
.iter
, uctx
, node
.node
) {
1350 ua_ctx
= alloc_ust_app_ctx(&uctx
->ctx
);
1351 if (ua_ctx
== NULL
) {
1354 lttng_ht_node_init_ulong(&ua_ctx
->node
,
1355 (unsigned long) ua_ctx
->ctx
.ctx
);
1356 lttng_ht_add_unique_ulong(ua_chan
->ctx
, &ua_ctx
->node
);
1359 /* Copy all events from ltt ust channel to ust app channel */
1360 cds_lfht_for_each_entry(uchan
->events
->ht
, &iter
.iter
, uevent
, node
.node
) {
1361 ua_event
= find_ust_app_event(ua_chan
->events
, uevent
->attr
.name
,
1362 uevent
->filter
, uevent
->attr
.loglevel
);
1363 if (ua_event
== NULL
) {
1364 DBG2("UST event %s not found on shadow copy channel",
1366 ua_event
= alloc_ust_app_event(uevent
->attr
.name
, &uevent
->attr
);
1367 if (ua_event
== NULL
) {
1370 shadow_copy_event(ua_event
, uevent
);
1371 add_unique_ust_app_event(ua_chan
, ua_event
);
1375 DBG3("UST app shadow copy of channel %s done", ua_chan
->name
);
1379 * Copy data between a UST app session and a regular LTT session.
1381 static void shadow_copy_session(struct ust_app_session
*ua_sess
,
1382 struct ltt_ust_session
*usess
, struct ust_app
*app
)
1384 struct lttng_ht_node_str
*ua_chan_node
;
1385 struct lttng_ht_iter iter
;
1386 struct ltt_ust_channel
*uchan
;
1387 struct ust_app_channel
*ua_chan
;
1389 struct tm
*timeinfo
;
1393 /* Get date and time for unique app path */
1395 timeinfo
= localtime(&rawtime
);
1396 strftime(datetime
, sizeof(datetime
), "%Y%m%d-%H%M%S", timeinfo
);
1398 DBG2("Shadow copy of session handle %d", ua_sess
->handle
);
1400 ua_sess
->tracing_id
= usess
->id
;
1401 ua_sess
->id
= get_next_session_id();
1402 ua_sess
->uid
= app
->uid
;
1403 ua_sess
->gid
= app
->gid
;
1404 ua_sess
->euid
= usess
->uid
;
1405 ua_sess
->egid
= usess
->gid
;
1406 ua_sess
->buffer_type
= usess
->buffer_type
;
1407 ua_sess
->bits_per_long
= app
->bits_per_long
;
1408 /* There is only one consumer object per session possible. */
1409 ua_sess
->consumer
= usess
->consumer
;
1411 switch (ua_sess
->buffer_type
) {
1412 case LTTNG_BUFFER_PER_PID
:
1413 ret
= snprintf(ua_sess
->path
, sizeof(ua_sess
->path
),
1414 DEFAULT_UST_TRACE_PID_PATH
"/%s-%d-%s", app
->name
, app
->pid
,
1417 case LTTNG_BUFFER_PER_UID
:
1418 ret
= snprintf(ua_sess
->path
, sizeof(ua_sess
->path
),
1419 DEFAULT_UST_TRACE_UID_PATH
, ua_sess
->uid
, app
->bits_per_long
);
1426 PERROR("asprintf UST shadow copy session");
1431 /* Iterate over all channels in global domain. */
1432 cds_lfht_for_each_entry(usess
->domain_global
.channels
->ht
, &iter
.iter
,
1434 struct lttng_ht_iter uiter
;
1436 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
1437 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
1438 if (ua_chan_node
!= NULL
) {
1439 /* Session exist. Contiuing. */
1443 DBG2("Channel %s not found on shadow session copy, creating it",
1445 ua_chan
= alloc_ust_app_channel(uchan
->name
, ua_sess
, &uchan
->attr
);
1446 if (ua_chan
== NULL
) {
1447 /* malloc failed FIXME: Might want to do handle ENOMEM .. */
1450 shadow_copy_channel(ua_chan
, uchan
);
1452 * The concept of metadata channel does not exist on the tracing
1453 * registry side of the session daemon so this can only be a per CPU
1454 * channel and not metadata.
1456 ua_chan
->attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1458 lttng_ht_add_unique_str(ua_sess
->channels
, &ua_chan
->node
);
1466 * Lookup sesison wrapper.
1469 void __lookup_session_by_app(struct ltt_ust_session
*usess
,
1470 struct ust_app
*app
, struct lttng_ht_iter
*iter
)
1472 /* Get right UST app session from app */
1473 lttng_ht_lookup(app
->sessions
, (void *)((unsigned long) usess
->id
), iter
);
1477 * Return ust app session from the app session hashtable using the UST session
1480 static struct ust_app_session
*lookup_session_by_app(
1481 struct ltt_ust_session
*usess
, struct ust_app
*app
)
1483 struct lttng_ht_iter iter
;
1484 struct lttng_ht_node_ulong
*node
;
1486 __lookup_session_by_app(usess
, app
, &iter
);
1487 node
= lttng_ht_iter_get_node_ulong(&iter
);
1492 return caa_container_of(node
, struct ust_app_session
, node
);
1499 * Setup buffer registry per PID for the given session and application. If none
1500 * is found, a new one is created, added to the global registry and
1501 * initialized. If regp is valid, it's set with the newly created object.
1503 * Return 0 on success or else a negative value.
1505 static int setup_buffer_reg_pid(struct ust_app_session
*ua_sess
,
1506 struct ust_app
*app
, struct buffer_reg_pid
**regp
)
1509 struct buffer_reg_pid
*reg_pid
;
1516 reg_pid
= buffer_reg_pid_find(ua_sess
->id
);
1519 * This is the create channel path meaning that if there is NO
1520 * registry available, we have to create one for this session.
1522 ret
= buffer_reg_pid_create(ua_sess
->id
, ®_pid
);
1526 buffer_reg_pid_add(reg_pid
);
1531 /* Initialize registry. */
1532 ret
= ust_registry_session_init(®_pid
->registry
->reg
.ust
, app
,
1533 app
->bits_per_long
, app
->uint8_t_alignment
,
1534 app
->uint16_t_alignment
, app
->uint32_t_alignment
,
1535 app
->uint64_t_alignment
, app
->long_alignment
,
1536 app
->byte_order
, app
->version
.major
,
1537 app
->version
.minor
);
1542 DBG3("UST app buffer registry per PID created successfully");
1554 * Setup buffer registry per UID for the given session and application. If none
1555 * is found, a new one is created, added to the global registry and
1556 * initialized. If regp is valid, it's set with the newly created object.
1558 * Return 0 on success or else a negative value.
1560 static int setup_buffer_reg_uid(struct ltt_ust_session
*usess
,
1561 struct ust_app
*app
, struct buffer_reg_uid
**regp
)
1564 struct buffer_reg_uid
*reg_uid
;
1571 reg_uid
= buffer_reg_uid_find(usess
->id
, app
->bits_per_long
, app
->uid
);
1574 * This is the create channel path meaning that if there is NO
1575 * registry available, we have to create one for this session.
1577 ret
= buffer_reg_uid_create(usess
->id
, app
->bits_per_long
, app
->uid
,
1578 LTTNG_DOMAIN_UST
, ®_uid
);
1582 buffer_reg_uid_add(reg_uid
);
1587 /* Initialize registry. */
1588 ret
= ust_registry_session_init(®_uid
->registry
->reg
.ust
, NULL
,
1589 app
->bits_per_long
, app
->uint8_t_alignment
,
1590 app
->uint16_t_alignment
, app
->uint32_t_alignment
,
1591 app
->uint64_t_alignment
, app
->long_alignment
,
1592 app
->byte_order
, app
->version
.major
,
1593 app
->version
.minor
);
1597 /* Add node to teardown list of the session. */
1598 cds_list_add(®_uid
->lnode
, &usess
->buffer_reg_uid_list
);
1600 DBG3("UST app buffer registry per UID created successfully");
1612 * Create a session on the tracer side for the given app.
1614 * On success, ua_sess_ptr is populated with the session pointer or else left
1615 * untouched. If the session was created, is_created is set to 1. On error,
1616 * it's left untouched. Note that ua_sess_ptr is mandatory but is_created can
1619 * Returns 0 on success or else a negative code which is either -ENOMEM or
1620 * -ENOTCONN which is the default code if the ustctl_create_session fails.
1622 static int create_ust_app_session(struct ltt_ust_session
*usess
,
1623 struct ust_app
*app
, struct ust_app_session
**ua_sess_ptr
,
1626 int ret
, created
= 0;
1627 struct ust_app_session
*ua_sess
;
1631 assert(ua_sess_ptr
);
1633 health_code_update();
1635 ua_sess
= lookup_session_by_app(usess
, app
);
1636 if (ua_sess
== NULL
) {
1637 DBG2("UST app pid: %d session id %d not found, creating it",
1638 app
->pid
, usess
->id
);
1639 ua_sess
= alloc_ust_app_session(app
);
1640 if (ua_sess
== NULL
) {
1641 /* Only malloc can failed so something is really wrong */
1645 shadow_copy_session(ua_sess
, usess
, app
);
1649 switch (usess
->buffer_type
) {
1650 case LTTNG_BUFFER_PER_PID
:
1651 /* Init local registry. */
1652 ret
= setup_buffer_reg_pid(ua_sess
, app
, NULL
);
1657 case LTTNG_BUFFER_PER_UID
:
1658 /* Look for a global registry. If none exists, create one. */
1659 ret
= setup_buffer_reg_uid(usess
, app
, NULL
);
1670 health_code_update();
1672 if (ua_sess
->handle
== -1) {
1673 ret
= ustctl_create_session(app
->sock
);
1675 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1676 ERR("Creating session for app pid %d with ret %d",
1679 DBG("UST app creating session failed. Application is dead");
1681 delete_ust_app_session(-1, ua_sess
, app
);
1682 if (ret
!= -ENOMEM
) {
1684 * Tracer is probably gone or got an internal error so let's
1685 * behave like it will soon unregister or not usable.
1692 ua_sess
->handle
= ret
;
1694 /* Add ust app session to app's HT */
1695 lttng_ht_node_init_ulong(&ua_sess
->node
,
1696 (unsigned long) ua_sess
->tracing_id
);
1697 lttng_ht_add_unique_ulong(app
->sessions
, &ua_sess
->node
);
1699 DBG2("UST app session created successfully with handle %d", ret
);
1702 *ua_sess_ptr
= ua_sess
;
1704 *is_created
= created
;
1707 /* Everything went well. */
1711 health_code_update();
1716 * Create a context for the channel on the tracer.
1718 * Called with UST app session lock held and a RCU read side lock.
1721 int create_ust_app_channel_context(struct ust_app_session
*ua_sess
,
1722 struct ust_app_channel
*ua_chan
, struct lttng_ust_context
*uctx
,
1723 struct ust_app
*app
)
1726 struct lttng_ht_iter iter
;
1727 struct lttng_ht_node_ulong
*node
;
1728 struct ust_app_ctx
*ua_ctx
;
1730 DBG2("UST app adding context to channel %s", ua_chan
->name
);
1732 lttng_ht_lookup(ua_chan
->ctx
, (void *)((unsigned long)uctx
->ctx
), &iter
);
1733 node
= lttng_ht_iter_get_node_ulong(&iter
);
1739 ua_ctx
= alloc_ust_app_ctx(uctx
);
1740 if (ua_ctx
== NULL
) {
1746 lttng_ht_node_init_ulong(&ua_ctx
->node
, (unsigned long) ua_ctx
->ctx
.ctx
);
1747 lttng_ht_add_unique_ulong(ua_chan
->ctx
, &ua_ctx
->node
);
1749 ret
= create_ust_channel_context(ua_chan
, ua_ctx
, app
);
1759 * Enable on the tracer side a ust app event for the session and channel.
1761 * Called with UST app session lock held.
1764 int enable_ust_app_event(struct ust_app_session
*ua_sess
,
1765 struct ust_app_event
*ua_event
, struct ust_app
*app
)
1769 ret
= enable_ust_event(app
, ua_sess
, ua_event
);
1774 ua_event
->enabled
= 1;
1781 * Disable on the tracer side a ust app event for the session and channel.
1783 static int disable_ust_app_event(struct ust_app_session
*ua_sess
,
1784 struct ust_app_event
*ua_event
, struct ust_app
*app
)
1788 ret
= disable_ust_event(app
, ua_sess
, ua_event
);
1793 ua_event
->enabled
= 0;
1800 * Lookup ust app channel for session and disable it on the tracer side.
1803 int disable_ust_app_channel(struct ust_app_session
*ua_sess
,
1804 struct ust_app_channel
*ua_chan
, struct ust_app
*app
)
1808 ret
= disable_ust_channel(app
, ua_sess
, ua_chan
);
1813 ua_chan
->enabled
= 0;
1820 * Lookup ust app channel for session and enable it on the tracer side. This
1821 * MUST be called with a RCU read side lock acquired.
1823 static int enable_ust_app_channel(struct ust_app_session
*ua_sess
,
1824 struct ltt_ust_channel
*uchan
, struct ust_app
*app
)
1827 struct lttng_ht_iter iter
;
1828 struct lttng_ht_node_str
*ua_chan_node
;
1829 struct ust_app_channel
*ua_chan
;
1831 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &iter
);
1832 ua_chan_node
= lttng_ht_iter_get_node_str(&iter
);
1833 if (ua_chan_node
== NULL
) {
1834 DBG2("Unable to find channel %s in ust session id %u",
1835 uchan
->name
, ua_sess
->tracing_id
);
1839 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
1841 ret
= enable_ust_channel(app
, ua_sess
, ua_chan
);
1851 * Ask the consumer to create a channel and get it if successful.
1853 * Return 0 on success or else a negative value.
1855 static int do_consumer_create_channel(struct ltt_ust_session
*usess
,
1856 struct ust_app_session
*ua_sess
, struct ust_app_channel
*ua_chan
,
1857 int bitness
, struct ust_registry_session
*registry
)
1860 unsigned int nb_fd
= 0;
1861 struct consumer_socket
*socket
;
1869 health_code_update();
1871 /* Get the right consumer socket for the application. */
1872 socket
= consumer_find_socket_by_bitness(bitness
, usess
->consumer
);
1878 health_code_update();
1880 /* Need one fd for the channel. */
1881 ret
= lttng_fd_get(LTTNG_FD_APPS
, 1);
1883 ERR("Exhausted number of available FD upon create channel");
1888 * Ask consumer to create channel. The consumer will return the number of
1889 * stream we have to expect.
1891 ret
= ust_consumer_ask_channel(ua_sess
, ua_chan
, usess
->consumer
, socket
,
1898 * Compute the number of fd needed before receiving them. It must be 2 per
1899 * stream (2 being the default value here).
1901 nb_fd
= DEFAULT_UST_STREAM_FD_NUM
* ua_chan
->expected_stream_count
;
1903 /* Reserve the amount of file descriptor we need. */
1904 ret
= lttng_fd_get(LTTNG_FD_APPS
, nb_fd
);
1906 ERR("Exhausted number of available FD upon create channel");
1907 goto error_fd_get_stream
;
1910 health_code_update();
1913 * Now get the channel from the consumer. This call wil populate the stream
1914 * list of that channel and set the ust objects.
1916 ret
= ust_consumer_get_channel(socket
, ua_chan
);
1925 lttng_fd_put(LTTNG_FD_APPS
, nb_fd
);
1926 error_fd_get_stream
:
1928 * Initiate a destroy channel on the consumer since we had an error
1929 * handling it on our side. The return value is of no importance since we
1930 * already have a ret value set by the previous error that we need to
1933 (void) ust_consumer_destroy_channel(socket
, ua_chan
);
1935 lttng_fd_put(LTTNG_FD_APPS
, 1);
1937 health_code_update();
1943 * Duplicate the ust data object of the ust app stream and save it in the
1944 * buffer registry stream.
1946 * Return 0 on success or else a negative value.
1948 static int duplicate_stream_object(struct buffer_reg_stream
*reg_stream
,
1949 struct ust_app_stream
*stream
)
1956 /* Reserve the amount of file descriptor we need. */
1957 ret
= lttng_fd_get(LTTNG_FD_APPS
, 2);
1959 ERR("Exhausted number of available FD upon duplicate stream");
1963 /* Duplicate object for stream once the original is in the registry. */
1964 ret
= ustctl_duplicate_ust_object_data(&stream
->obj
,
1965 reg_stream
->obj
.ust
);
1967 ERR("Duplicate stream obj from %p to %p failed with ret %d",
1968 reg_stream
->obj
.ust
, stream
->obj
, ret
);
1969 lttng_fd_put(LTTNG_FD_APPS
, 2);
1972 stream
->handle
= stream
->obj
->handle
;
1979 * Duplicate the ust data object of the ust app. channel and save it in the
1980 * buffer registry channel.
1982 * Return 0 on success or else a negative value.
1984 static int duplicate_channel_object(struct buffer_reg_channel
*reg_chan
,
1985 struct ust_app_channel
*ua_chan
)
1992 /* Need two fds for the channel. */
1993 ret
= lttng_fd_get(LTTNG_FD_APPS
, 1);
1995 ERR("Exhausted number of available FD upon duplicate channel");
1999 /* Duplicate object for stream once the original is in the registry. */
2000 ret
= ustctl_duplicate_ust_object_data(&ua_chan
->obj
, reg_chan
->obj
.ust
);
2002 ERR("Duplicate channel obj from %p to %p failed with ret: %d",
2003 reg_chan
->obj
.ust
, ua_chan
->obj
, ret
);
2006 ua_chan
->handle
= ua_chan
->obj
->handle
;
2011 lttng_fd_put(LTTNG_FD_APPS
, 1);
2017 * For a given channel buffer registry, setup all streams of the given ust
2018 * application channel.
2020 * Return 0 on success or else a negative value.
2022 static int setup_buffer_reg_streams(struct buffer_reg_channel
*reg_chan
,
2023 struct ust_app_channel
*ua_chan
)
2026 struct ust_app_stream
*stream
, *stmp
;
2031 DBG2("UST app setup buffer registry stream");
2033 /* Send all streams to application. */
2034 cds_list_for_each_entry_safe(stream
, stmp
, &ua_chan
->streams
.head
, list
) {
2035 struct buffer_reg_stream
*reg_stream
;
2037 ret
= buffer_reg_stream_create(®_stream
);
2043 * Keep original pointer and nullify it in the stream so the delete
2044 * stream call does not release the object.
2046 reg_stream
->obj
.ust
= stream
->obj
;
2048 buffer_reg_stream_add(reg_stream
, reg_chan
);
2050 /* We don't need the streams anymore. */
2051 cds_list_del(&stream
->list
);
2052 delete_ust_app_stream(-1, stream
);
2060 * Create a buffer registry channel for the given session registry and
2061 * application channel object. If regp pointer is valid, it's set with the
2062 * created object. Important, the created object is NOT added to the session
2063 * registry hash table.
2065 * Return 0 on success else a negative value.
2067 static int create_buffer_reg_channel(struct buffer_reg_session
*reg_sess
,
2068 struct ust_app_channel
*ua_chan
, struct buffer_reg_channel
**regp
)
2071 struct buffer_reg_channel
*reg_chan
= NULL
;
2076 DBG2("UST app creating buffer registry channel for %s", ua_chan
->name
);
2078 /* Create buffer registry channel. */
2079 ret
= buffer_reg_channel_create(ua_chan
->tracing_channel_id
, ®_chan
);
2084 reg_chan
->consumer_key
= ua_chan
->key
;
2086 /* Create and add a channel registry to session. */
2087 ret
= ust_registry_channel_add(reg_sess
->reg
.ust
,
2088 ua_chan
->tracing_channel_id
);
2092 buffer_reg_channel_add(reg_sess
, reg_chan
);
2101 /* Safe because the registry channel object was not added to any HT. */
2102 buffer_reg_channel_destroy(reg_chan
, LTTNG_DOMAIN_UST
);
2108 * Setup buffer registry channel for the given session registry and application
2109 * channel object. If regp pointer is valid, it's set with the created object.
2111 * Return 0 on success else a negative value.
2113 static int setup_buffer_reg_channel(struct buffer_reg_session
*reg_sess
,
2114 struct ust_app_channel
*ua_chan
, struct buffer_reg_channel
*reg_chan
)
2121 assert(ua_chan
->obj
);
2123 DBG2("UST app setup buffer registry channel for %s", ua_chan
->name
);
2125 /* Setup all streams for the registry. */
2126 ret
= setup_buffer_reg_streams(reg_chan
, ua_chan
);
2131 reg_chan
->obj
.ust
= ua_chan
->obj
;
2132 ua_chan
->obj
= NULL
;
2137 buffer_reg_channel_remove(reg_sess
, reg_chan
);
2138 buffer_reg_channel_destroy(reg_chan
, LTTNG_DOMAIN_UST
);
2143 * Send buffer registry channel to the application.
2145 * Return 0 on success else a negative value.
2147 static int send_channel_uid_to_ust(struct buffer_reg_channel
*reg_chan
,
2148 struct ust_app
*app
, struct ust_app_session
*ua_sess
,
2149 struct ust_app_channel
*ua_chan
)
2152 struct buffer_reg_stream
*reg_stream
;
2159 DBG("UST app sending buffer registry channel to ust sock %d", app
->sock
);
2161 ret
= duplicate_channel_object(reg_chan
, ua_chan
);
2166 /* Send channel to the application. */
2167 ret
= ust_consumer_send_channel_to_ust(app
, ua_sess
, ua_chan
);
2172 health_code_update();
2174 /* Send all streams to application. */
2175 pthread_mutex_lock(®_chan
->stream_list_lock
);
2176 cds_list_for_each_entry(reg_stream
, ®_chan
->streams
, lnode
) {
2177 struct ust_app_stream stream
;
2179 ret
= duplicate_stream_object(reg_stream
, &stream
);
2181 goto error_stream_unlock
;
2184 ret
= ust_consumer_send_stream_to_ust(app
, ua_chan
, &stream
);
2186 (void) release_ust_app_stream(-1, &stream
);
2187 goto error_stream_unlock
;
2191 * The return value is not important here. This function will output an
2194 (void) release_ust_app_stream(-1, &stream
);
2196 ua_chan
->is_sent
= 1;
2198 error_stream_unlock
:
2199 pthread_mutex_unlock(®_chan
->stream_list_lock
);
2205 * Create and send to the application the created buffers with per UID buffers.
2207 * Return 0 on success else a negative value.
2209 static int create_channel_per_uid(struct ust_app
*app
,
2210 struct ltt_ust_session
*usess
, struct ust_app_session
*ua_sess
,
2211 struct ust_app_channel
*ua_chan
)
2214 struct buffer_reg_uid
*reg_uid
;
2215 struct buffer_reg_channel
*reg_chan
;
2222 DBG("UST app creating channel %s with per UID buffers", ua_chan
->name
);
2224 reg_uid
= buffer_reg_uid_find(usess
->id
, app
->bits_per_long
, app
->uid
);
2226 * The session creation handles the creation of this global registry
2227 * object. If none can be find, there is a code flow problem or a
2232 reg_chan
= buffer_reg_channel_find(ua_chan
->tracing_channel_id
,
2235 /* Create the buffer registry channel object. */
2236 ret
= create_buffer_reg_channel(reg_uid
->registry
, ua_chan
, ®_chan
);
2243 * Create the buffers on the consumer side. This call populates the
2244 * ust app channel object with all streams and data object.
2246 ret
= do_consumer_create_channel(usess
, ua_sess
, ua_chan
,
2247 app
->bits_per_long
, reg_uid
->registry
->reg
.ust
);
2253 * Setup the streams and add it to the session registry.
2255 ret
= setup_buffer_reg_channel(reg_uid
->registry
, ua_chan
, reg_chan
);
2262 /* Send buffers to the application. */
2263 ret
= send_channel_uid_to_ust(reg_chan
, app
, ua_sess
, ua_chan
);
2273 * Create and send to the application the created buffers with per PID buffers.
2275 * Return 0 on success else a negative value.
2277 static int create_channel_per_pid(struct ust_app
*app
,
2278 struct ltt_ust_session
*usess
, struct ust_app_session
*ua_sess
,
2279 struct ust_app_channel
*ua_chan
)
2282 struct ust_registry_session
*registry
;
2289 DBG("UST app creating channel %s with per PID buffers", ua_chan
->name
);
2293 registry
= get_session_registry(ua_sess
);
2296 /* Create and add a new channel registry to session. */
2297 ret
= ust_registry_channel_add(registry
, ua_chan
->key
);
2302 /* Create and get channel on the consumer side. */
2303 ret
= do_consumer_create_channel(usess
, ua_sess
, ua_chan
,
2304 app
->bits_per_long
, registry
);
2309 ret
= send_channel_pid_to_ust(app
, ua_sess
, ua_chan
);
2320 * From an already allocated ust app channel, create the channel buffers if
2321 * need and send it to the application. This MUST be called with a RCU read
2322 * side lock acquired.
2324 * Return 0 on success or else a negative value.
2326 static int do_create_channel(struct ust_app
*app
,
2327 struct ltt_ust_session
*usess
, struct ust_app_session
*ua_sess
,
2328 struct ust_app_channel
*ua_chan
)
2337 /* Handle buffer type before sending the channel to the application. */
2338 switch (usess
->buffer_type
) {
2339 case LTTNG_BUFFER_PER_UID
:
2341 ret
= create_channel_per_uid(app
, usess
, ua_sess
, ua_chan
);
2347 case LTTNG_BUFFER_PER_PID
:
2349 ret
= create_channel_per_pid(app
, usess
, ua_sess
, ua_chan
);
2361 /* Initialize ust objd object using the received handle and add it. */
2362 lttng_ht_node_init_ulong(&ua_chan
->ust_objd_node
, ua_chan
->handle
);
2363 lttng_ht_add_unique_ulong(app
->ust_objd
, &ua_chan
->ust_objd_node
);
2365 /* If channel is not enabled, disable it on the tracer */
2366 if (!ua_chan
->enabled
) {
2367 ret
= disable_ust_channel(app
, ua_sess
, ua_chan
);
2378 * Create UST app channel and create it on the tracer. Set ua_chanp of the
2379 * newly created channel if not NULL.
2381 * Called with UST app session lock and RCU read-side lock held.
2383 * Return 0 on success or else a negative value.
2385 static int create_ust_app_channel(struct ust_app_session
*ua_sess
,
2386 struct ltt_ust_channel
*uchan
, struct ust_app
*app
,
2387 enum lttng_ust_chan_type type
, struct ltt_ust_session
*usess
,
2388 struct ust_app_channel
**ua_chanp
)
2391 struct lttng_ht_iter iter
;
2392 struct lttng_ht_node_str
*ua_chan_node
;
2393 struct ust_app_channel
*ua_chan
;
2395 /* Lookup channel in the ust app session */
2396 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &iter
);
2397 ua_chan_node
= lttng_ht_iter_get_node_str(&iter
);
2398 if (ua_chan_node
!= NULL
) {
2399 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
2403 ua_chan
= alloc_ust_app_channel(uchan
->name
, ua_sess
, &uchan
->attr
);
2404 if (ua_chan
== NULL
) {
2405 /* Only malloc can fail here */
2409 shadow_copy_channel(ua_chan
, uchan
);
2411 /* Set channel type. */
2412 ua_chan
->attr
.type
= type
;
2414 ret
= do_create_channel(app
, usess
, ua_sess
, ua_chan
);
2419 DBG2("UST app create channel %s for PID %d completed", ua_chan
->name
,
2422 /* Only add the channel if successful on the tracer side. */
2423 lttng_ht_add_unique_str(ua_sess
->channels
, &ua_chan
->node
);
2427 *ua_chanp
= ua_chan
;
2430 /* Everything went well. */
2434 delete_ust_app_channel(ua_chan
->is_sent
? app
->sock
: -1, ua_chan
, app
);
2439 * Create UST app event and create it on the tracer side.
2441 * Called with ust app session mutex held.
2444 int create_ust_app_event(struct ust_app_session
*ua_sess
,
2445 struct ust_app_channel
*ua_chan
, struct ltt_ust_event
*uevent
,
2446 struct ust_app
*app
)
2449 struct ust_app_event
*ua_event
;
2451 /* Get event node */
2452 ua_event
= find_ust_app_event(ua_chan
->events
, uevent
->attr
.name
,
2453 uevent
->filter
, uevent
->attr
.loglevel
);
2454 if (ua_event
!= NULL
) {
2459 /* Does not exist so create one */
2460 ua_event
= alloc_ust_app_event(uevent
->attr
.name
, &uevent
->attr
);
2461 if (ua_event
== NULL
) {
2462 /* Only malloc can failed so something is really wrong */
2466 shadow_copy_event(ua_event
, uevent
);
2468 /* Create it on the tracer side */
2469 ret
= create_ust_event(app
, ua_sess
, ua_chan
, ua_event
);
2471 /* Not found previously means that it does not exist on the tracer */
2472 assert(ret
!= -LTTNG_UST_ERR_EXIST
);
2476 add_unique_ust_app_event(ua_chan
, ua_event
);
2478 DBG2("UST app create event %s for PID %d completed", ua_event
->name
,
2485 /* Valid. Calling here is already in a read side lock */
2486 delete_ust_app_event(-1, ua_event
);
2491 * Create UST metadata and open it on the tracer side.
2493 * Called with UST app session lock held and RCU read side lock.
2495 static int create_ust_app_metadata(struct ust_app_session
*ua_sess
,
2496 struct ust_app
*app
, struct consumer_output
*consumer
,
2497 struct ustctl_consumer_channel_attr
*attr
)
2500 struct ust_app_channel
*metadata
;
2501 struct consumer_socket
*socket
;
2502 struct ust_registry_session
*registry
;
2508 registry
= get_session_registry(ua_sess
);
2511 /* Metadata already exists for this registry. */
2512 if (registry
->metadata_key
) {
2517 /* Allocate UST metadata */
2518 metadata
= alloc_ust_app_channel(DEFAULT_METADATA_NAME
, ua_sess
, NULL
);
2520 /* malloc() failed */
2526 /* Set default attributes for metadata. */
2527 metadata
->attr
.overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
2528 metadata
->attr
.subbuf_size
= default_get_metadata_subbuf_size();
2529 metadata
->attr
.num_subbuf
= DEFAULT_METADATA_SUBBUF_NUM
;
2530 metadata
->attr
.switch_timer_interval
= DEFAULT_UST_CHANNEL_SWITCH_TIMER
;
2531 metadata
->attr
.read_timer_interval
= DEFAULT_UST_CHANNEL_READ_TIMER
;
2532 metadata
->attr
.output
= LTTNG_UST_MMAP
;
2533 metadata
->attr
.type
= LTTNG_UST_CHAN_METADATA
;
2535 memcpy(&metadata
->attr
, attr
, sizeof(metadata
->attr
));
2536 metadata
->attr
.output
= LTTNG_UST_MMAP
;
2537 metadata
->attr
.type
= LTTNG_UST_CHAN_METADATA
;
2540 /* Get the right consumer socket for the application. */
2541 socket
= consumer_find_socket_by_bitness(app
->bits_per_long
, consumer
);
2544 goto error_consumer
;
2547 /* Need one fd for the channel. */
2548 ret
= lttng_fd_get(LTTNG_FD_APPS
, 1);
2550 ERR("Exhausted number of available FD upon create metadata");
2555 * Keep metadata key so we can identify it on the consumer side. Assign it
2556 * to the registry *before* we ask the consumer so we avoid the race of the
2557 * consumer requesting the metadata and the ask_channel call on our side
2558 * did not returned yet.
2560 registry
->metadata_key
= metadata
->key
;
2563 * Ask the metadata channel creation to the consumer. The metadata object
2564 * will be created by the consumer and kept their. However, the stream is
2565 * never added or monitored until we do a first push metadata to the
2568 ret
= ust_consumer_ask_channel(ua_sess
, metadata
, consumer
, socket
,
2572 * Safe because the metadata obj pointer is not set so the delete below
2573 * will not put a FD back again.
2575 goto error_consumer
;
2579 * The setup command will make the metadata stream be sent to the relayd,
2580 * if applicable, and the thread managing the metadatas. This is important
2581 * because after this point, if an error occurs, the only way the stream
2582 * can be deleted is to be monitored in the consumer.
2584 ret
= consumer_setup_metadata(socket
, metadata
->key
);
2587 * Safe because the metadata obj pointer is not set so the delete below
2588 * will not put a FD back again.
2590 goto error_consumer
;
2593 DBG2("UST metadata with key %" PRIu64
" created for app pid %d",
2594 metadata
->key
, app
->pid
);
2597 lttng_fd_put(LTTNG_FD_APPS
, 1);
2598 delete_ust_app_channel(-1, metadata
, app
);
2604 * Return pointer to traceable apps list.
2606 struct lttng_ht
*ust_app_get_ht(void)
2612 * Return ust app pointer or NULL if not found. RCU read side lock MUST be
2613 * acquired before calling this function.
2615 struct ust_app
*ust_app_find_by_pid(pid_t pid
)
2617 struct ust_app
*app
= NULL
;
2618 struct lttng_ht_node_ulong
*node
;
2619 struct lttng_ht_iter iter
;
2621 lttng_ht_lookup(ust_app_ht
, (void *)((unsigned long) pid
), &iter
);
2622 node
= lttng_ht_iter_get_node_ulong(&iter
);
2624 DBG2("UST app no found with pid %d", pid
);
2628 DBG2("Found UST app by pid %d", pid
);
2630 app
= caa_container_of(node
, struct ust_app
, pid_n
);
2637 * Allocate and init an UST app object using the registration information and
2638 * the command socket. This is called when the command socket connects to the
2641 * The object is returned on success or else NULL.
2643 struct ust_app
*ust_app_create(struct ust_register_msg
*msg
, int sock
)
2645 struct ust_app
*lta
= NULL
;
2650 DBG3("UST app creating application for socket %d", sock
);
2652 if ((msg
->bits_per_long
== 64 &&
2653 (uatomic_read(&ust_consumerd64_fd
) == -EINVAL
))
2654 || (msg
->bits_per_long
== 32 &&
2655 (uatomic_read(&ust_consumerd32_fd
) == -EINVAL
))) {
2656 ERR("Registration failed: application \"%s\" (pid: %d) has "
2657 "%d-bit long, but no consumerd for this size is available.\n",
2658 msg
->name
, msg
->pid
, msg
->bits_per_long
);
2662 lta
= zmalloc(sizeof(struct ust_app
));
2668 lta
->ppid
= msg
->ppid
;
2669 lta
->uid
= msg
->uid
;
2670 lta
->gid
= msg
->gid
;
2672 lta
->bits_per_long
= msg
->bits_per_long
;
2673 lta
->uint8_t_alignment
= msg
->uint8_t_alignment
;
2674 lta
->uint16_t_alignment
= msg
->uint16_t_alignment
;
2675 lta
->uint32_t_alignment
= msg
->uint32_t_alignment
;
2676 lta
->uint64_t_alignment
= msg
->uint64_t_alignment
;
2677 lta
->long_alignment
= msg
->long_alignment
;
2678 lta
->byte_order
= msg
->byte_order
;
2680 lta
->v_major
= msg
->major
;
2681 lta
->v_minor
= msg
->minor
;
2682 lta
->sessions
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
2683 lta
->ust_objd
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
2684 lta
->notify_sock
= -1;
2686 /* Copy name and make sure it's NULL terminated. */
2687 strncpy(lta
->name
, msg
->name
, sizeof(lta
->name
));
2688 lta
->name
[UST_APP_PROCNAME_LEN
] = '\0';
2691 * Before this can be called, when receiving the registration information,
2692 * the application compatibility is checked. So, at this point, the
2693 * application can work with this session daemon.
2695 lta
->compatible
= 1;
2697 lta
->pid
= msg
->pid
;
2698 lttng_ht_node_init_ulong(<a
->pid_n
, (unsigned long) lta
->pid
);
2700 lttng_ht_node_init_ulong(<a
->sock_n
, (unsigned long) lta
->sock
);
2702 CDS_INIT_LIST_HEAD(<a
->teardown_head
);
2709 * For a given application object, add it to every hash table.
2711 void ust_app_add(struct ust_app
*app
)
2714 assert(app
->notify_sock
>= 0);
2719 * On a re-registration, we want to kick out the previous registration of
2722 lttng_ht_add_replace_ulong(ust_app_ht
, &app
->pid_n
);
2725 * The socket _should_ be unique until _we_ call close. So, a add_unique
2726 * for the ust_app_ht_by_sock is used which asserts fail if the entry was
2727 * already in the table.
2729 lttng_ht_add_unique_ulong(ust_app_ht_by_sock
, &app
->sock_n
);
2731 /* Add application to the notify socket hash table. */
2732 lttng_ht_node_init_ulong(&app
->notify_sock_n
, app
->notify_sock
);
2733 lttng_ht_add_unique_ulong(ust_app_ht_by_notify_sock
, &app
->notify_sock_n
);
2735 DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s "
2736 "notify_sock:%d (version %d.%d)", app
->pid
, app
->ppid
, app
->uid
,
2737 app
->gid
, app
->sock
, app
->name
, app
->notify_sock
, app
->v_major
,
2744 * Set the application version into the object.
2746 * Return 0 on success else a negative value either an errno code or a
2747 * LTTng-UST error code.
2749 int ust_app_version(struct ust_app
*app
)
2755 ret
= ustctl_tracer_version(app
->sock
, &app
->version
);
2757 if (ret
!= -LTTNG_UST_ERR_EXITING
&& ret
!= -EPIPE
) {
2758 ERR("UST app %d verson failed with ret %d", app
->sock
, ret
);
2760 DBG3("UST app %d verion failed. Application is dead", app
->sock
);
2768 * Unregister app by removing it from the global traceable app list and freeing
2771 * The socket is already closed at this point so no close to sock.
2773 void ust_app_unregister(int sock
)
2775 struct ust_app
*lta
;
2776 struct lttng_ht_node_ulong
*node
;
2777 struct lttng_ht_iter iter
;
2778 struct ust_app_session
*ua_sess
;
2783 /* Get the node reference for a call_rcu */
2784 lttng_ht_lookup(ust_app_ht_by_sock
, (void *)((unsigned long) sock
), &iter
);
2785 node
= lttng_ht_iter_get_node_ulong(&iter
);
2788 lta
= caa_container_of(node
, struct ust_app
, sock_n
);
2789 DBG("PID %d unregistering with sock %d", lta
->pid
, sock
);
2791 /* Remove application from PID hash table */
2792 ret
= lttng_ht_del(ust_app_ht_by_sock
, &iter
);
2796 * Remove application from notify hash table. The thread handling the
2797 * notify socket could have deleted the node so ignore on error because
2798 * either way it's valid. The close of that socket is handled by the other
2801 iter
.iter
.node
= <a
->notify_sock_n
.node
;
2802 (void) lttng_ht_del(ust_app_ht_by_notify_sock
, &iter
);
2805 * Ignore return value since the node might have been removed before by an
2806 * add replace during app registration because the PID can be reassigned by
2809 iter
.iter
.node
= <a
->pid_n
.node
;
2810 ret
= lttng_ht_del(ust_app_ht
, &iter
);
2812 DBG3("Unregister app by PID %d failed. This can happen on pid reuse",
2816 /* Remove sessions so they are not visible during deletion.*/
2817 cds_lfht_for_each_entry(lta
->sessions
->ht
, &iter
.iter
, ua_sess
,
2819 struct ust_registry_session
*registry
;
2821 ret
= lttng_ht_del(lta
->sessions
, &iter
);
2823 /* The session was already removed so scheduled for teardown. */
2828 * Add session to list for teardown. This is safe since at this point we
2829 * are the only one using this list.
2831 pthread_mutex_lock(&ua_sess
->lock
);
2834 * Normally, this is done in the delete session process which is
2835 * executed in the call rcu below. However, upon registration we can't
2836 * afford to wait for the grace period before pushing data or else the
2837 * data pending feature can race between the unregistration and stop
2838 * command where the data pending command is sent *before* the grace
2841 * The close metadata below nullifies the metadata pointer in the
2842 * session so the delete session will NOT push/close a second time.
2844 registry
= get_session_registry(ua_sess
);
2846 /* Push metadata for application before freeing the application. */
2847 (void) push_metadata(registry
, ua_sess
->consumer
);
2850 * Don't ask to close metadata for global per UID buffers. Close
2851 * metadata only on destroy trace session in this case.
2853 if (ua_sess
->buffer_type
!= LTTNG_BUFFER_PER_UID
) {
2854 /* And ask to close it for this session registry. */
2855 (void) close_metadata(registry
, ua_sess
->consumer
);
2859 cds_list_add(&ua_sess
->teardown_node
, <a
->teardown_head
);
2860 pthread_mutex_unlock(&ua_sess
->lock
);
2864 call_rcu(<a
->pid_n
.head
, delete_ust_app_rcu
);
2871 * Return traceable_app_count
2873 unsigned long ust_app_list_count(void)
2875 unsigned long count
;
2878 count
= lttng_ht_get_count(ust_app_ht
);
2885 * Fill events array with all events name of all registered apps.
2887 int ust_app_list_events(struct lttng_event
**events
)
2890 size_t nbmem
, count
= 0;
2891 struct lttng_ht_iter iter
;
2892 struct ust_app
*app
;
2893 struct lttng_event
*tmp_event
;
2895 nbmem
= UST_APP_EVENT_LIST_SIZE
;
2896 tmp_event
= zmalloc(nbmem
* sizeof(struct lttng_event
));
2897 if (tmp_event
== NULL
) {
2898 PERROR("zmalloc ust app events");
2905 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
2906 struct lttng_ust_tracepoint_iter uiter
;
2908 health_code_update();
2910 if (!app
->compatible
) {
2912 * TODO: In time, we should notice the caller of this error by
2913 * telling him that this is a version error.
2917 handle
= ustctl_tracepoint_list(app
->sock
);
2919 if (handle
!= -EPIPE
&& handle
!= -LTTNG_UST_ERR_EXITING
) {
2920 ERR("UST app list events getting handle failed for app pid %d",
2926 while ((ret
= ustctl_tracepoint_list_get(app
->sock
, handle
,
2927 &uiter
)) != -LTTNG_UST_ERR_NOENT
) {
2928 /* Handle ustctl error. */
2931 if (ret
!= -LTTNG_UST_ERR_EXITING
|| ret
!= -EPIPE
) {
2932 ERR("UST app tp list get failed for app %d with ret %d",
2935 DBG3("UST app tp list get failed. Application is dead");
2940 health_code_update();
2941 if (count
>= nbmem
) {
2942 /* In case the realloc fails, we free the memory */
2945 DBG2("Reallocating event list from %zu to %zu entries", nbmem
,
2948 ptr
= realloc(tmp_event
, nbmem
* sizeof(struct lttng_event
));
2950 PERROR("realloc ust app events");
2957 memcpy(tmp_event
[count
].name
, uiter
.name
, LTTNG_UST_SYM_NAME_LEN
);
2958 tmp_event
[count
].loglevel
= uiter
.loglevel
;
2959 tmp_event
[count
].type
= (enum lttng_event_type
) LTTNG_UST_TRACEPOINT
;
2960 tmp_event
[count
].pid
= app
->pid
;
2961 tmp_event
[count
].enabled
= -1;
2967 *events
= tmp_event
;
2969 DBG2("UST app list events done (%zu events)", count
);
2974 health_code_update();
2979 * Fill events array with all events name of all registered apps.
2981 int ust_app_list_event_fields(struct lttng_event_field
**fields
)
2984 size_t nbmem
, count
= 0;
2985 struct lttng_ht_iter iter
;
2986 struct ust_app
*app
;
2987 struct lttng_event_field
*tmp_event
;
2989 nbmem
= UST_APP_EVENT_LIST_SIZE
;
2990 tmp_event
= zmalloc(nbmem
* sizeof(struct lttng_event_field
));
2991 if (tmp_event
== NULL
) {
2992 PERROR("zmalloc ust app event fields");
2999 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3000 struct lttng_ust_field_iter uiter
;
3002 health_code_update();
3004 if (!app
->compatible
) {
3006 * TODO: In time, we should notice the caller of this error by
3007 * telling him that this is a version error.
3011 handle
= ustctl_tracepoint_field_list(app
->sock
);
3013 if (handle
!= -EPIPE
&& handle
!= -LTTNG_UST_ERR_EXITING
) {
3014 ERR("UST app list field getting handle failed for app pid %d",
3020 while ((ret
= ustctl_tracepoint_field_list_get(app
->sock
, handle
,
3021 &uiter
)) != -LTTNG_UST_ERR_NOENT
) {
3022 /* Handle ustctl error. */
3025 if (ret
!= -LTTNG_UST_ERR_EXITING
|| ret
!= -EPIPE
) {
3026 ERR("UST app tp list field failed for app %d with ret %d",
3029 DBG3("UST app tp list field failed. Application is dead");
3034 health_code_update();
3035 if (count
>= nbmem
) {
3036 /* In case the realloc fails, we free the memory */
3039 DBG2("Reallocating event field list from %zu to %zu entries", nbmem
,
3042 ptr
= realloc(tmp_event
, nbmem
* sizeof(struct lttng_event_field
));
3044 PERROR("realloc ust app event fields");
3052 memcpy(tmp_event
[count
].field_name
, uiter
.field_name
, LTTNG_UST_SYM_NAME_LEN
);
3053 tmp_event
[count
].type
= uiter
.type
;
3054 tmp_event
[count
].nowrite
= uiter
.nowrite
;
3056 memcpy(tmp_event
[count
].event
.name
, uiter
.event_name
, LTTNG_UST_SYM_NAME_LEN
);
3057 tmp_event
[count
].event
.loglevel
= uiter
.loglevel
;
3058 tmp_event
[count
].event
.type
= LTTNG_UST_TRACEPOINT
;
3059 tmp_event
[count
].event
.pid
= app
->pid
;
3060 tmp_event
[count
].event
.enabled
= -1;
3066 *fields
= tmp_event
;
3068 DBG2("UST app list event fields done (%zu events)", count
);
3073 health_code_update();
3078 * Free and clean all traceable apps of the global list.
3080 * Should _NOT_ be called with RCU read-side lock held.
3082 void ust_app_clean_list(void)
3085 struct ust_app
*app
;
3086 struct lttng_ht_iter iter
;
3088 DBG2("UST app cleaning registered apps hash table");
3092 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3093 ret
= lttng_ht_del(ust_app_ht
, &iter
);
3095 call_rcu(&app
->pid_n
.head
, delete_ust_app_rcu
);
3098 /* Cleanup socket hash table */
3099 cds_lfht_for_each_entry(ust_app_ht_by_sock
->ht
, &iter
.iter
, app
,
3101 ret
= lttng_ht_del(ust_app_ht_by_sock
, &iter
);
3105 /* Cleanup notify socket hash table */
3106 cds_lfht_for_each_entry(ust_app_ht_by_notify_sock
->ht
, &iter
.iter
, app
,
3107 notify_sock_n
.node
) {
3108 ret
= lttng_ht_del(ust_app_ht_by_notify_sock
, &iter
);
3113 /* Destroy is done only when the ht is empty */
3114 lttng_ht_destroy(ust_app_ht
);
3115 lttng_ht_destroy(ust_app_ht_by_sock
);
3116 lttng_ht_destroy(ust_app_ht_by_notify_sock
);
3120 * Init UST app hash table.
3122 void ust_app_ht_alloc(void)
3124 ust_app_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
3125 ust_app_ht_by_sock
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
3126 ust_app_ht_by_notify_sock
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
3130 * For a specific UST session, disable the channel for all registered apps.
3132 int ust_app_disable_channel_glb(struct ltt_ust_session
*usess
,
3133 struct ltt_ust_channel
*uchan
)
3136 struct lttng_ht_iter iter
;
3137 struct lttng_ht_node_str
*ua_chan_node
;
3138 struct ust_app
*app
;
3139 struct ust_app_session
*ua_sess
;
3140 struct ust_app_channel
*ua_chan
;
3142 if (usess
== NULL
|| uchan
== NULL
) {
3143 ERR("Disabling UST global channel with NULL values");
3148 DBG2("UST app disabling channel %s from global domain for session id %d",
3149 uchan
->name
, usess
->id
);
3153 /* For every registered applications */
3154 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3155 struct lttng_ht_iter uiter
;
3156 if (!app
->compatible
) {
3158 * TODO: In time, we should notice the caller of this error by
3159 * telling him that this is a version error.
3163 ua_sess
= lookup_session_by_app(usess
, app
);
3164 if (ua_sess
== NULL
) {
3169 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
3170 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
3171 /* If the session if found for the app, the channel must be there */
3172 assert(ua_chan_node
);
3174 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
3175 /* The channel must not be already disabled */
3176 assert(ua_chan
->enabled
== 1);
3178 /* Disable channel onto application */
3179 ret
= disable_ust_app_channel(ua_sess
, ua_chan
, app
);
3181 /* XXX: We might want to report this error at some point... */
3193 * For a specific UST session, enable the channel for all registered apps.
3195 int ust_app_enable_channel_glb(struct ltt_ust_session
*usess
,
3196 struct ltt_ust_channel
*uchan
)
3199 struct lttng_ht_iter iter
;
3200 struct ust_app
*app
;
3201 struct ust_app_session
*ua_sess
;
3203 if (usess
== NULL
|| uchan
== NULL
) {
3204 ERR("Adding UST global channel to NULL values");
3209 DBG2("UST app enabling channel %s to global domain for session id %d",
3210 uchan
->name
, usess
->id
);
3214 /* For every registered applications */
3215 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3216 if (!app
->compatible
) {
3218 * TODO: In time, we should notice the caller of this error by
3219 * telling him that this is a version error.
3223 ua_sess
= lookup_session_by_app(usess
, app
);
3224 if (ua_sess
== NULL
) {
3228 /* Enable channel onto application */
3229 ret
= enable_ust_app_channel(ua_sess
, uchan
, app
);
3231 /* XXX: We might want to report this error at some point... */
3243 * Disable an event in a channel and for a specific session.
3245 int ust_app_disable_event_glb(struct ltt_ust_session
*usess
,
3246 struct ltt_ust_channel
*uchan
, struct ltt_ust_event
*uevent
)
3249 struct lttng_ht_iter iter
, uiter
;
3250 struct lttng_ht_node_str
*ua_chan_node
, *ua_event_node
;
3251 struct ust_app
*app
;
3252 struct ust_app_session
*ua_sess
;
3253 struct ust_app_channel
*ua_chan
;
3254 struct ust_app_event
*ua_event
;
3256 DBG("UST app disabling event %s for all apps in channel "
3257 "%s for session id %d", uevent
->attr
.name
, uchan
->name
, usess
->id
);
3261 /* For all registered applications */
3262 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3263 if (!app
->compatible
) {
3265 * TODO: In time, we should notice the caller of this error by
3266 * telling him that this is a version error.
3270 ua_sess
= lookup_session_by_app(usess
, app
);
3271 if (ua_sess
== NULL
) {
3276 /* Lookup channel in the ust app session */
3277 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
3278 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
3279 if (ua_chan_node
== NULL
) {
3280 DBG2("Channel %s not found in session id %d for app pid %d."
3281 "Skipping", uchan
->name
, usess
->id
, app
->pid
);
3284 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
3286 lttng_ht_lookup(ua_chan
->events
, (void *)uevent
->attr
.name
, &uiter
);
3287 ua_event_node
= lttng_ht_iter_get_node_str(&uiter
);
3288 if (ua_event_node
== NULL
) {
3289 DBG2("Event %s not found in channel %s for app pid %d."
3290 "Skipping", uevent
->attr
.name
, uchan
->name
, app
->pid
);
3293 ua_event
= caa_container_of(ua_event_node
, struct ust_app_event
, node
);
3295 ret
= disable_ust_app_event(ua_sess
, ua_event
, app
);
3297 /* XXX: Report error someday... */
3308 * For a specific UST session and UST channel, the event for all
3311 int ust_app_disable_all_event_glb(struct ltt_ust_session
*usess
,
3312 struct ltt_ust_channel
*uchan
)
3315 struct lttng_ht_iter iter
, uiter
;
3316 struct lttng_ht_node_str
*ua_chan_node
;
3317 struct ust_app
*app
;
3318 struct ust_app_session
*ua_sess
;
3319 struct ust_app_channel
*ua_chan
;
3320 struct ust_app_event
*ua_event
;
3322 DBG("UST app disabling all event for all apps in channel "
3323 "%s for session id %d", uchan
->name
, usess
->id
);
3327 /* For all registered applications */
3328 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3329 if (!app
->compatible
) {
3331 * TODO: In time, we should notice the caller of this error by
3332 * telling him that this is a version error.
3336 ua_sess
= lookup_session_by_app(usess
, app
);
3338 /* The application has problem or is probably dead. */
3342 /* Lookup channel in the ust app session */
3343 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
3344 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
3345 /* If the channel is not found, there is a code flow error */
3346 assert(ua_chan_node
);
3348 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
3350 /* Disable each events of channel */
3351 cds_lfht_for_each_entry(ua_chan
->events
->ht
, &uiter
.iter
, ua_event
,
3353 ret
= disable_ust_app_event(ua_sess
, ua_event
, app
);
3355 /* XXX: Report error someday... */
3367 * For a specific UST session, create the channel for all registered apps.
3369 int ust_app_create_channel_glb(struct ltt_ust_session
*usess
,
3370 struct ltt_ust_channel
*uchan
)
3372 int ret
= 0, created
;
3373 struct lttng_ht_iter iter
;
3374 struct ust_app
*app
;
3375 struct ust_app_session
*ua_sess
= NULL
;
3377 /* Very wrong code flow */
3381 DBG2("UST app adding channel %s to UST domain for session id %d",
3382 uchan
->name
, usess
->id
);
3386 /* For every registered applications */
3387 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3388 if (!app
->compatible
) {
3390 * TODO: In time, we should notice the caller of this error by
3391 * telling him that this is a version error.
3396 * Create session on the tracer side and add it to app session HT. Note
3397 * that if session exist, it will simply return a pointer to the ust
3400 ret
= create_ust_app_session(usess
, app
, &ua_sess
, &created
);
3405 * The application's socket is not valid. Either a bad socket
3406 * or a timeout on it. We can't inform the caller that for a
3407 * specific app, the session failed so lets continue here.
3412 goto error_rcu_unlock
;
3417 pthread_mutex_lock(&ua_sess
->lock
);
3418 if (!strncmp(uchan
->name
, DEFAULT_METADATA_NAME
,
3419 sizeof(uchan
->name
))) {
3420 struct ustctl_consumer_channel_attr attr
;
3421 copy_channel_attr_to_ustctl(&attr
, &uchan
->attr
);
3422 ret
= create_ust_app_metadata(ua_sess
, app
, usess
->consumer
,
3425 /* Create channel onto application. We don't need the chan ref. */
3426 ret
= create_ust_app_channel(ua_sess
, uchan
, app
,
3427 LTTNG_UST_CHAN_PER_CPU
, usess
, NULL
);
3429 pthread_mutex_unlock(&ua_sess
->lock
);
3431 if (ret
== -ENOMEM
) {
3432 /* No more memory is a fatal error. Stop right now. */
3433 goto error_rcu_unlock
;
3435 /* Cleanup the created session if it's the case. */
3437 destroy_app_session(app
, ua_sess
);
3448 * Enable event for a specific session and channel on the tracer.
3450 int ust_app_enable_event_glb(struct ltt_ust_session
*usess
,
3451 struct ltt_ust_channel
*uchan
, struct ltt_ust_event
*uevent
)
3454 struct lttng_ht_iter iter
, uiter
;
3455 struct lttng_ht_node_str
*ua_chan_node
;
3456 struct ust_app
*app
;
3457 struct ust_app_session
*ua_sess
;
3458 struct ust_app_channel
*ua_chan
;
3459 struct ust_app_event
*ua_event
;
3461 DBG("UST app enabling event %s for all apps for session id %d",
3462 uevent
->attr
.name
, usess
->id
);
3465 * NOTE: At this point, this function is called only if the session and
3466 * channel passed are already created for all apps. and enabled on the
3472 /* For all registered applications */
3473 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3474 if (!app
->compatible
) {
3476 * TODO: In time, we should notice the caller of this error by
3477 * telling him that this is a version error.
3481 ua_sess
= lookup_session_by_app(usess
, app
);
3483 /* The application has problem or is probably dead. */
3487 pthread_mutex_lock(&ua_sess
->lock
);
3489 /* Lookup channel in the ust app session */
3490 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
3491 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
3492 /* If the channel is not found, there is a code flow error */
3493 assert(ua_chan_node
);
3495 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
3497 /* Get event node */
3498 ua_event
= find_ust_app_event(ua_chan
->events
, uevent
->attr
.name
,
3499 uevent
->filter
, uevent
->attr
.loglevel
);
3500 if (ua_event
== NULL
) {
3501 DBG3("UST app enable event %s not found for app PID %d."
3502 "Skipping app", uevent
->attr
.name
, app
->pid
);
3506 ret
= enable_ust_app_event(ua_sess
, ua_event
, app
);
3508 pthread_mutex_unlock(&ua_sess
->lock
);
3512 pthread_mutex_unlock(&ua_sess
->lock
);
3521 * For a specific existing UST session and UST channel, creates the event for
3522 * all registered apps.
3524 int ust_app_create_event_glb(struct ltt_ust_session
*usess
,
3525 struct ltt_ust_channel
*uchan
, struct ltt_ust_event
*uevent
)
3528 struct lttng_ht_iter iter
, uiter
;
3529 struct lttng_ht_node_str
*ua_chan_node
;
3530 struct ust_app
*app
;
3531 struct ust_app_session
*ua_sess
;
3532 struct ust_app_channel
*ua_chan
;
3534 DBG("UST app creating event %s for all apps for session id %d",
3535 uevent
->attr
.name
, usess
->id
);
3539 /* For all registered applications */
3540 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3541 if (!app
->compatible
) {
3543 * TODO: In time, we should notice the caller of this error by
3544 * telling him that this is a version error.
3548 ua_sess
= lookup_session_by_app(usess
, app
);
3550 /* The application has problem or is probably dead. */
3554 pthread_mutex_lock(&ua_sess
->lock
);
3555 /* Lookup channel in the ust app session */
3556 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
3557 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
3558 /* If the channel is not found, there is a code flow error */
3559 assert(ua_chan_node
);
3561 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
3563 ret
= create_ust_app_event(ua_sess
, ua_chan
, uevent
, app
);
3564 pthread_mutex_unlock(&ua_sess
->lock
);
3566 if (ret
!= -LTTNG_UST_ERR_EXIST
) {
3567 /* Possible value at this point: -ENOMEM. If so, we stop! */
3570 DBG2("UST app event %s already exist on app PID %d",
3571 uevent
->attr
.name
, app
->pid
);
3582 * Start tracing for a specific UST session and app.
3585 int ust_app_start_trace(struct ltt_ust_session
*usess
, struct ust_app
*app
)
3588 struct ust_app_session
*ua_sess
;
3590 DBG("Starting tracing for ust app pid %d", app
->pid
);
3594 if (!app
->compatible
) {
3598 ua_sess
= lookup_session_by_app(usess
, app
);
3599 if (ua_sess
== NULL
) {
3600 /* The session is in teardown process. Ignore and continue. */
3604 pthread_mutex_lock(&ua_sess
->lock
);
3606 /* Upon restart, we skip the setup, already done */
3607 if (ua_sess
->started
) {
3611 /* Create directories if consumer is LOCAL and has a path defined. */
3612 if (usess
->consumer
->type
== CONSUMER_DST_LOCAL
&&
3613 strlen(usess
->consumer
->dst
.trace_path
) > 0) {
3614 ret
= run_as_mkdir_recursive(usess
->consumer
->dst
.trace_path
,
3615 S_IRWXU
| S_IRWXG
, ua_sess
->euid
, ua_sess
->egid
);
3617 if (ret
!= -EEXIST
) {
3618 ERR("Trace directory creation error");
3625 * Create the metadata for the application. This returns gracefully if a
3626 * metadata was already set for the session.
3628 ret
= create_ust_app_metadata(ua_sess
, app
, usess
->consumer
, NULL
);
3633 health_code_update();
3636 /* This start the UST tracing */
3637 ret
= ustctl_start_session(app
->sock
, ua_sess
->handle
);
3639 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3640 ERR("Error starting tracing for app pid: %d (ret: %d)",
3643 DBG("UST app start session failed. Application is dead.");
3648 /* Indicate that the session has been started once */
3649 ua_sess
->started
= 1;
3651 pthread_mutex_unlock(&ua_sess
->lock
);
3653 health_code_update();
3655 /* Quiescent wait after starting trace */
3656 ret
= ustctl_wait_quiescent(app
->sock
);
3657 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3658 ERR("UST app wait quiescent failed for app pid %d ret %d",
3664 health_code_update();
3668 pthread_mutex_unlock(&ua_sess
->lock
);
3670 health_code_update();
3675 * Stop tracing for a specific UST session and app.
3678 int ust_app_stop_trace(struct ltt_ust_session
*usess
, struct ust_app
*app
)
3681 struct ust_app_session
*ua_sess
;
3682 struct ust_registry_session
*registry
;
3684 DBG("Stopping tracing for ust app pid %d", app
->pid
);
3688 if (!app
->compatible
) {
3689 goto end_no_session
;
3692 ua_sess
= lookup_session_by_app(usess
, app
);
3693 if (ua_sess
== NULL
) {
3694 goto end_no_session
;
3697 pthread_mutex_lock(&ua_sess
->lock
);
3700 * If started = 0, it means that stop trace has been called for a session
3701 * that was never started. It's possible since we can have a fail start
3702 * from either the application manager thread or the command thread. Simply
3703 * indicate that this is a stop error.
3705 if (!ua_sess
->started
) {
3706 goto error_rcu_unlock
;
3709 health_code_update();
3711 /* This inhibits UST tracing */
3712 ret
= ustctl_stop_session(app
->sock
, ua_sess
->handle
);
3714 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3715 ERR("Error stopping tracing for app pid: %d (ret: %d)",
3718 DBG("UST app stop session failed. Application is dead.");
3720 goto error_rcu_unlock
;
3723 health_code_update();
3725 /* Quiescent wait after stopping trace */
3726 ret
= ustctl_wait_quiescent(app
->sock
);
3727 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3728 ERR("UST app wait quiescent failed for app pid %d ret %d",
3732 health_code_update();
3734 registry
= get_session_registry(ua_sess
);
3736 /* Push metadata for application before freeing the application. */
3737 (void) push_metadata(registry
, ua_sess
->consumer
);
3739 pthread_mutex_unlock(&ua_sess
->lock
);
3742 health_code_update();
3746 pthread_mutex_unlock(&ua_sess
->lock
);
3748 health_code_update();
3753 * Flush buffers for a specific UST session and app.
3756 int ust_app_flush_trace(struct ltt_ust_session
*usess
, struct ust_app
*app
)
3759 struct lttng_ht_iter iter
;
3760 struct ust_app_session
*ua_sess
;
3761 struct ust_app_channel
*ua_chan
;
3763 DBG("Flushing buffers for ust app pid %d", app
->pid
);
3767 if (!app
->compatible
) {
3768 goto end_no_session
;
3771 ua_sess
= lookup_session_by_app(usess
, app
);
3772 if (ua_sess
== NULL
) {
3773 goto end_no_session
;
3776 pthread_mutex_lock(&ua_sess
->lock
);
3778 health_code_update();
3780 /* Flushing buffers */
3781 cds_lfht_for_each_entry(ua_sess
->channels
->ht
, &iter
.iter
, ua_chan
,
3783 health_code_update();
3784 assert(ua_chan
->is_sent
);
3785 ret
= ustctl_sock_flush_buffer(app
->sock
, ua_chan
->obj
);
3787 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3788 ERR("UST app PID %d channel %s flush failed with ret %d",
3789 app
->pid
, ua_chan
->name
, ret
);
3791 DBG3("UST app failed to flush %s. Application is dead.",
3793 /* No need to continue. */
3796 /* Continuing flushing all buffers */
3801 health_code_update();
3803 pthread_mutex_unlock(&ua_sess
->lock
);
3806 health_code_update();
3811 * Destroy a specific UST session in apps.
3813 static int destroy_trace(struct ltt_ust_session
*usess
, struct ust_app
*app
)
3816 struct ust_app_session
*ua_sess
;
3817 struct lttng_ht_iter iter
;
3818 struct lttng_ht_node_ulong
*node
;
3820 DBG("Destroy tracing for ust app pid %d", app
->pid
);
3824 if (!app
->compatible
) {
3828 __lookup_session_by_app(usess
, app
, &iter
);
3829 node
= lttng_ht_iter_get_node_ulong(&iter
);
3831 /* Session is being or is deleted. */
3834 ua_sess
= caa_container_of(node
, struct ust_app_session
, node
);
3836 health_code_update();
3837 destroy_app_session(app
, ua_sess
);
3839 health_code_update();
3841 /* Quiescent wait after stopping trace */
3842 ret
= ustctl_wait_quiescent(app
->sock
);
3843 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3844 ERR("UST app wait quiescent failed for app pid %d ret %d",
3849 health_code_update();
3854 * Start tracing for the UST session.
3856 int ust_app_start_trace_all(struct ltt_ust_session
*usess
)
3859 struct lttng_ht_iter iter
;
3860 struct ust_app
*app
;
3862 DBG("Starting all UST traces");
3866 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3867 ret
= ust_app_start_trace(usess
, app
);
3869 /* Continue to next apps even on error */
3880 * Start tracing for the UST session.
3882 int ust_app_stop_trace_all(struct ltt_ust_session
*usess
)
3885 struct lttng_ht_iter iter
;
3886 struct ust_app
*app
;
3888 DBG("Stopping all UST traces");
3892 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3893 ret
= ust_app_stop_trace(usess
, app
);
3895 /* Continue to next apps even on error */
3901 switch (usess
->buffer_type
) {
3902 case LTTNG_BUFFER_PER_UID
:
3904 struct buffer_reg_uid
*reg
;
3906 /* Flush all per UID buffers associated to that session. */
3907 cds_list_for_each_entry(reg
, &usess
->buffer_reg_uid_list
, lnode
) {
3908 struct buffer_reg_channel
*reg_chan
;
3909 struct consumer_socket
*socket
;
3911 /* Get consumer socket to use to push the metadata.*/
3912 socket
= consumer_find_socket_by_bitness(reg
->bits_per_long
,
3915 /* Ignore request if no consumer is found for the session. */
3919 cds_lfht_for_each_entry(reg
->registry
->channels
->ht
, &iter
.iter
,
3920 reg_chan
, node
.node
) {
3922 * The following call will print error values so the return
3923 * code is of little importance because whatever happens, we
3924 * have to try them all.
3926 (void) consumer_flush_channel(socket
, reg_chan
->consumer_key
);
3931 case LTTNG_BUFFER_PER_PID
:
3932 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3933 ret
= ust_app_flush_trace(usess
, app
);
3935 /* Continue to next apps even on error */
3951 * Destroy app UST session.
3953 int ust_app_destroy_trace_all(struct ltt_ust_session
*usess
)
3956 struct lttng_ht_iter iter
;
3957 struct ust_app
*app
;
3959 DBG("Destroy all UST traces");
3963 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3964 ret
= destroy_trace(usess
, app
);
3966 /* Continue to next apps even on error */
3977 * Add channels/events from UST global domain to registered apps at sock.
3979 void ust_app_global_update(struct ltt_ust_session
*usess
, int sock
)
3982 struct lttng_ht_iter iter
, uiter
, iter_ctx
;
3983 struct ust_app
*app
;
3984 struct ust_app_session
*ua_sess
= NULL
;
3985 struct ust_app_channel
*ua_chan
;
3986 struct ust_app_event
*ua_event
;
3987 struct ust_app_ctx
*ua_ctx
;
3992 DBG2("UST app global update for app sock %d for session id %d", sock
,
3997 app
= find_app_by_sock(sock
);
4000 * Application can be unregistered before so this is possible hence
4001 * simply stopping the update.
4003 DBG3("UST app update failed to find app sock %d", sock
);
4007 if (!app
->compatible
) {
4011 ret
= create_ust_app_session(usess
, app
, &ua_sess
, NULL
);
4013 /* Tracer is probably gone or ENOMEM. */
4018 pthread_mutex_lock(&ua_sess
->lock
);
4021 * We can iterate safely here over all UST app session since the create ust
4022 * app session above made a shadow copy of the UST global domain from the
4025 cds_lfht_for_each_entry(ua_sess
->channels
->ht
, &iter
.iter
, ua_chan
,
4028 * For a metadata channel, handle it differently.
4030 if (!strncmp(ua_chan
->name
, DEFAULT_METADATA_NAME
,
4031 sizeof(ua_chan
->name
))) {
4032 ret
= create_ust_app_metadata(ua_sess
, app
, usess
->consumer
,
4037 /* Remove it from the hash table and continue!. */
4038 ret
= lttng_ht_del(ua_sess
->channels
, &iter
);
4040 delete_ust_app_channel(-1, ua_chan
, app
);
4043 ret
= do_create_channel(app
, usess
, ua_sess
, ua_chan
);
4046 * Stop everything. On error, the application failed, no more
4047 * file descriptor are available or ENOMEM so stopping here is
4048 * the only thing we can do for now.
4054 cds_lfht_for_each_entry(ua_chan
->ctx
->ht
, &iter_ctx
.iter
, ua_ctx
,
4056 ret
= create_ust_channel_context(ua_chan
, ua_ctx
, app
);
4063 /* For each events */
4064 cds_lfht_for_each_entry(ua_chan
->events
->ht
, &uiter
.iter
, ua_event
,
4066 ret
= create_ust_event(app
, ua_sess
, ua_chan
, ua_event
);
4073 pthread_mutex_unlock(&ua_sess
->lock
);
4075 if (usess
->start_trace
) {
4076 ret
= ust_app_start_trace(usess
, app
);
4081 DBG2("UST trace started for app pid %d", app
->pid
);
4084 /* Everything went well at this point. */
4089 pthread_mutex_unlock(&ua_sess
->lock
);
4092 destroy_app_session(app
, ua_sess
);
4099 * Add context to a specific channel for global UST domain.
4101 int ust_app_add_ctx_channel_glb(struct ltt_ust_session
*usess
,
4102 struct ltt_ust_channel
*uchan
, struct ltt_ust_context
*uctx
)
4105 struct lttng_ht_node_str
*ua_chan_node
;
4106 struct lttng_ht_iter iter
, uiter
;
4107 struct ust_app_channel
*ua_chan
= NULL
;
4108 struct ust_app_session
*ua_sess
;
4109 struct ust_app
*app
;
4113 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
4114 if (!app
->compatible
) {
4116 * TODO: In time, we should notice the caller of this error by
4117 * telling him that this is a version error.
4121 ua_sess
= lookup_session_by_app(usess
, app
);
4122 if (ua_sess
== NULL
) {
4126 pthread_mutex_lock(&ua_sess
->lock
);
4127 /* Lookup channel in the ust app session */
4128 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
4129 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
4130 if (ua_chan_node
== NULL
) {
4133 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
,
4135 ret
= create_ust_app_channel_context(ua_sess
, ua_chan
, &uctx
->ctx
, app
);
4140 pthread_mutex_unlock(&ua_sess
->lock
);
4148 * Enable event for a channel from a UST session for a specific PID.
4150 int ust_app_enable_event_pid(struct ltt_ust_session
*usess
,
4151 struct ltt_ust_channel
*uchan
, struct ltt_ust_event
*uevent
, pid_t pid
)
4154 struct lttng_ht_iter iter
;
4155 struct lttng_ht_node_str
*ua_chan_node
;
4156 struct ust_app
*app
;
4157 struct ust_app_session
*ua_sess
;
4158 struct ust_app_channel
*ua_chan
;
4159 struct ust_app_event
*ua_event
;
4161 DBG("UST app enabling event %s for PID %d", uevent
->attr
.name
, pid
);
4165 app
= ust_app_find_by_pid(pid
);
4167 ERR("UST app enable event per PID %d not found", pid
);
4172 if (!app
->compatible
) {
4177 ua_sess
= lookup_session_by_app(usess
, app
);
4179 /* The application has problem or is probably dead. */
4184 pthread_mutex_lock(&ua_sess
->lock
);
4185 /* Lookup channel in the ust app session */
4186 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &iter
);
4187 ua_chan_node
= lttng_ht_iter_get_node_str(&iter
);
4188 /* If the channel is not found, there is a code flow error */
4189 assert(ua_chan_node
);
4191 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
4193 ua_event
= find_ust_app_event(ua_chan
->events
, uevent
->attr
.name
,
4194 uevent
->filter
, uevent
->attr
.loglevel
);
4195 if (ua_event
== NULL
) {
4196 ret
= create_ust_app_event(ua_sess
, ua_chan
, uevent
, app
);
4201 ret
= enable_ust_app_event(ua_sess
, ua_event
, app
);
4208 pthread_mutex_unlock(&ua_sess
->lock
);
4215 * Disable event for a channel from a UST session for a specific PID.
4217 int ust_app_disable_event_pid(struct ltt_ust_session
*usess
,
4218 struct ltt_ust_channel
*uchan
, struct ltt_ust_event
*uevent
, pid_t pid
)
4221 struct lttng_ht_iter iter
;
4222 struct lttng_ht_node_str
*ua_chan_node
, *ua_event_node
;
4223 struct ust_app
*app
;
4224 struct ust_app_session
*ua_sess
;
4225 struct ust_app_channel
*ua_chan
;
4226 struct ust_app_event
*ua_event
;
4228 DBG("UST app disabling event %s for PID %d", uevent
->attr
.name
, pid
);
4232 app
= ust_app_find_by_pid(pid
);
4234 ERR("UST app disable event per PID %d not found", pid
);
4239 if (!app
->compatible
) {
4244 ua_sess
= lookup_session_by_app(usess
, app
);
4246 /* The application has problem or is probably dead. */
4250 /* Lookup channel in the ust app session */
4251 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &iter
);
4252 ua_chan_node
= lttng_ht_iter_get_node_str(&iter
);
4253 if (ua_chan_node
== NULL
) {
4254 /* Channel does not exist, skip disabling */
4257 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
4259 lttng_ht_lookup(ua_chan
->events
, (void *)uevent
->attr
.name
, &iter
);
4260 ua_event_node
= lttng_ht_iter_get_node_str(&iter
);
4261 if (ua_event_node
== NULL
) {
4262 /* Event does not exist, skip disabling */
4265 ua_event
= caa_container_of(ua_event_node
, struct ust_app_event
, node
);
4267 ret
= disable_ust_app_event(ua_sess
, ua_event
, app
);
4278 * Calibrate registered applications.
4280 int ust_app_calibrate_glb(struct lttng_ust_calibrate
*calibrate
)
4283 struct lttng_ht_iter iter
;
4284 struct ust_app
*app
;
4288 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
4289 if (!app
->compatible
) {
4291 * TODO: In time, we should notice the caller of this error by
4292 * telling him that this is a version error.
4297 health_code_update();
4299 ret
= ustctl_calibrate(app
->sock
, calibrate
);
4303 /* Means that it's not implemented on the tracer side. */
4307 DBG2("Calibrate app PID %d returned with error %d",
4314 DBG("UST app global domain calibration finished");
4318 health_code_update();
4324 * Receive registration and populate the given msg structure.
4326 * On success return 0 else a negative value returned by the ustctl call.
4328 int ust_app_recv_registration(int sock
, struct ust_register_msg
*msg
)
4331 uint32_t pid
, ppid
, uid
, gid
;
4335 ret
= ustctl_recv_reg_msg(sock
, &msg
->type
, &msg
->major
, &msg
->minor
,
4336 &pid
, &ppid
, &uid
, &gid
,
4337 &msg
->bits_per_long
,
4338 &msg
->uint8_t_alignment
,
4339 &msg
->uint16_t_alignment
,
4340 &msg
->uint32_t_alignment
,
4341 &msg
->uint64_t_alignment
,
4342 &msg
->long_alignment
,
4349 case LTTNG_UST_ERR_EXITING
:
4350 DBG3("UST app recv reg message failed. Application died");
4352 case LTTNG_UST_ERR_UNSUP_MAJOR
:
4353 ERR("UST app recv reg unsupported version %d.%d. Supporting %d.%d",
4354 msg
->major
, msg
->minor
, LTTNG_UST_ABI_MAJOR_VERSION
,
4355 LTTNG_UST_ABI_MINOR_VERSION
);
4358 ERR("UST app recv reg message failed with ret %d", ret
);
4363 msg
->pid
= (pid_t
) pid
;
4364 msg
->ppid
= (pid_t
) ppid
;
4365 msg
->uid
= (uid_t
) uid
;
4366 msg
->gid
= (gid_t
) gid
;
4373 * Return a ust app channel object using the application object and the channel
4374 * object descriptor has a key. If not found, NULL is returned. A RCU read side
4375 * lock MUST be acquired before calling this function.
4377 static struct ust_app_channel
*find_channel_by_objd(struct ust_app
*app
,
4380 struct lttng_ht_node_ulong
*node
;
4381 struct lttng_ht_iter iter
;
4382 struct ust_app_channel
*ua_chan
= NULL
;
4386 lttng_ht_lookup(app
->ust_objd
, (void *)((unsigned long) objd
), &iter
);
4387 node
= lttng_ht_iter_get_node_ulong(&iter
);
4389 DBG2("UST app channel find by objd %d not found", objd
);
4393 ua_chan
= caa_container_of(node
, struct ust_app_channel
, ust_objd_node
);
4400 * Reply to a register channel notification from an application on the notify
4401 * socket. The channel metadata is also created.
4403 * The session UST registry lock is acquired in this function.
4405 * On success 0 is returned else a negative value.
4407 static int reply_ust_register_channel(int sock
, int sobjd
, int cobjd
,
4408 size_t nr_fields
, struct ustctl_field
*fields
)
4410 int ret
, ret_code
= 0;
4411 uint32_t chan_id
, reg_count
;
4412 uint64_t chan_reg_key
;
4413 enum ustctl_channel_header type
;
4414 struct ust_app
*app
;
4415 struct ust_app_channel
*ua_chan
;
4416 struct ust_app_session
*ua_sess
;
4417 struct ust_registry_session
*registry
;
4418 struct ust_registry_channel
*chan_reg
;
4422 /* Lookup application. If not found, there is a code flow error. */
4423 app
= find_app_by_notify_sock(sock
);
4425 DBG("Application socket %d is being teardown. Abort event notify",
4428 goto error_rcu_unlock
;
4431 /* Lookup channel by UST object descriptor. Should always be found. */
4432 ua_chan
= find_channel_by_objd(app
, cobjd
);
4434 assert(ua_chan
->session
);
4435 ua_sess
= ua_chan
->session
;
4437 /* Get right session registry depending on the session buffer type. */
4438 registry
= get_session_registry(ua_sess
);
4441 /* Depending on the buffer type, a different channel key is used. */
4442 if (ua_sess
->buffer_type
== LTTNG_BUFFER_PER_UID
) {
4443 chan_reg_key
= ua_chan
->tracing_channel_id
;
4445 chan_reg_key
= ua_chan
->key
;
4448 pthread_mutex_lock(®istry
->lock
);
4450 chan_reg
= ust_registry_channel_find(registry
, chan_reg_key
);
4453 if (!chan_reg
->register_done
) {
4454 reg_count
= ust_registry_get_event_count(chan_reg
);
4455 if (reg_count
< 31) {
4456 type
= USTCTL_CHANNEL_HEADER_COMPACT
;
4458 type
= USTCTL_CHANNEL_HEADER_LARGE
;
4461 chan_reg
->nr_ctx_fields
= nr_fields
;
4462 chan_reg
->ctx_fields
= fields
;
4463 chan_reg
->header_type
= type
;
4465 /* Get current already assigned values. */
4466 type
= chan_reg
->header_type
;
4468 /* Channel id is set during the object creation. */
4469 chan_id
= chan_reg
->chan_id
;
4471 /* Append to metadata */
4472 if (!chan_reg
->metadata_dumped
) {
4473 ret_code
= ust_metadata_channel_statedump(registry
, chan_reg
);
4475 ERR("Error appending channel metadata (errno = %d)", ret_code
);
4481 DBG3("UST app replying to register channel key %" PRIu64
4482 " with id %u, type: %d, ret: %d", chan_reg_key
, chan_id
, type
,
4485 ret
= ustctl_reply_register_channel(sock
, chan_id
, type
, ret_code
);
4487 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
4488 ERR("UST app reply channel failed with ret %d", ret
);
4490 DBG3("UST app reply channel failed. Application died");
4495 /* This channel registry registration is completed. */
4496 chan_reg
->register_done
= 1;
4499 pthread_mutex_unlock(®istry
->lock
);
4506 * Add event to the UST channel registry. When the event is added to the
4507 * registry, the metadata is also created. Once done, this replies to the
4508 * application with the appropriate error code.
4510 * The session UST registry lock is acquired in the function.
4512 * On success 0 is returned else a negative value.
4514 static int add_event_ust_registry(int sock
, int sobjd
, int cobjd
, char *name
,
4515 char *sig
, size_t nr_fields
, struct ustctl_field
*fields
, int loglevel
,
4516 char *model_emf_uri
)
4519 uint32_t event_id
= 0;
4520 uint64_t chan_reg_key
;
4521 struct ust_app
*app
;
4522 struct ust_app_channel
*ua_chan
;
4523 struct ust_app_session
*ua_sess
;
4524 struct ust_registry_session
*registry
;
4528 /* Lookup application. If not found, there is a code flow error. */
4529 app
= find_app_by_notify_sock(sock
);
4531 DBG("Application socket %d is being teardown. Abort event notify",
4534 goto error_rcu_unlock
;
4537 /* Lookup channel by UST object descriptor. Should always be found. */
4538 ua_chan
= find_channel_by_objd(app
, cobjd
);
4540 assert(ua_chan
->session
);
4541 ua_sess
= ua_chan
->session
;
4543 registry
= get_session_registry(ua_sess
);
4546 if (ua_sess
->buffer_type
== LTTNG_BUFFER_PER_UID
) {
4547 chan_reg_key
= ua_chan
->tracing_channel_id
;
4549 chan_reg_key
= ua_chan
->key
;
4552 pthread_mutex_lock(®istry
->lock
);
4554 ret_code
= ust_registry_create_event(registry
, chan_reg_key
,
4555 sobjd
, cobjd
, name
, sig
, nr_fields
, fields
, loglevel
,
4556 model_emf_uri
, ua_sess
->buffer_type
, &event_id
);
4559 * The return value is returned to ustctl so in case of an error, the
4560 * application can be notified. In case of an error, it's important not to
4561 * return a negative error or else the application will get closed.
4563 ret
= ustctl_reply_register_event(sock
, event_id
, ret_code
);
4565 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
4566 ERR("UST app reply event failed with ret %d", ret
);
4568 DBG3("UST app reply event failed. Application died");
4571 * No need to wipe the create event since the application socket will
4572 * get close on error hence cleaning up everything by itself.
4577 DBG3("UST registry event %s with id %" PRId32
" added successfully",
4581 pthread_mutex_unlock(®istry
->lock
);
4588 * Handle application notification through the given notify socket.
4590 * Return 0 on success or else a negative value.
4592 int ust_app_recv_notify(int sock
)
4595 enum ustctl_notify_cmd cmd
;
4597 DBG3("UST app receiving notify from sock %d", sock
);
4599 ret
= ustctl_recv_notify(sock
, &cmd
);
4601 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
4602 ERR("UST app recv notify failed with ret %d", ret
);
4604 DBG3("UST app recv notify failed. Application died");
4610 case USTCTL_NOTIFY_CMD_EVENT
:
4612 int sobjd
, cobjd
, loglevel
;
4613 char name
[LTTNG_UST_SYM_NAME_LEN
], *sig
, *model_emf_uri
;
4615 struct ustctl_field
*fields
;
4617 DBG2("UST app ustctl register event received");
4619 ret
= ustctl_recv_register_event(sock
, &sobjd
, &cobjd
, name
, &loglevel
,
4620 &sig
, &nr_fields
, &fields
, &model_emf_uri
);
4622 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
4623 ERR("UST app recv event failed with ret %d", ret
);
4625 DBG3("UST app recv event failed. Application died");
4630 /* Add event to the UST registry coming from the notify socket. */
4631 ret
= add_event_ust_registry(sock
, sobjd
, cobjd
, name
, sig
, nr_fields
,
4632 fields
, loglevel
, model_emf_uri
);
4639 case USTCTL_NOTIFY_CMD_CHANNEL
:
4643 struct ustctl_field
*fields
;
4645 DBG2("UST app ustctl register channel received");
4647 ret
= ustctl_recv_register_channel(sock
, &sobjd
, &cobjd
, &nr_fields
,
4650 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
4651 ERR("UST app recv channel failed with ret %d", ret
);
4653 DBG3("UST app recv channel failed. Application died");
4658 ret
= reply_ust_register_channel(sock
, sobjd
, cobjd
, nr_fields
,
4667 /* Should NEVER happen. */
4676 * Once the notify socket hangs up, this is called. First, it tries to find the
4677 * corresponding application. On failure, the call_rcu to close the socket is
4678 * executed. If an application is found, it tries to delete it from the notify
4679 * socket hash table. Whathever the result, it proceeds to the call_rcu.
4681 * Note that an object needs to be allocated here so on ENOMEM failure, the
4682 * call RCU is not done but the rest of the cleanup is.
4684 void ust_app_notify_sock_unregister(int sock
)
4687 struct lttng_ht_iter iter
;
4688 struct ust_app
*app
;
4689 struct ust_app_notify_sock_obj
*obj
;
4695 obj
= zmalloc(sizeof(*obj
));
4698 * An ENOMEM is kind of uncool. If this strikes we continue the
4699 * procedure but the call_rcu will not be called. In this case, we
4700 * accept the fd leak rather than possibly creating an unsynchronized
4701 * state between threads.
4703 * TODO: The notify object should be created once the notify socket is
4704 * registered and stored independantely from the ust app object. The
4705 * tricky part is to synchronize the teardown of the application and
4706 * this notify object. Let's keep that in mind so we can avoid this
4707 * kind of shenanigans with ENOMEM in the teardown path.
4714 DBG("UST app notify socket unregister %d", sock
);
4717 * Lookup application by notify socket. If this fails, this means that the
4718 * hash table delete has already been done by the application
4719 * unregistration process so we can safely close the notify socket in a
4722 app
= find_app_by_notify_sock(sock
);
4727 iter
.iter
.node
= &app
->notify_sock_n
.node
;
4730 * Whatever happens here either we fail or succeed, in both cases we have
4731 * to close the socket after a grace period to continue to the call RCU
4732 * here. If the deletion is successful, the application is not visible
4733 * anymore by other threads and is it fails it means that it was already
4734 * deleted from the hash table so either way we just have to close the
4737 (void) lttng_ht_del(ust_app_ht_by_notify_sock
, &iter
);
4743 * Close socket after a grace period to avoid for the socket to be reused
4744 * before the application object is freed creating potential race between
4745 * threads trying to add unique in the global hash table.
4748 call_rcu(&obj
->head
, close_notify_sock_rcu
);