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 * Delete ust app channel safely. RCU read lock must be held before calling
313 void delete_ust_app_channel(int sock
, struct ust_app_channel
*ua_chan
,
317 struct lttng_ht_iter iter
;
318 struct ust_app_event
*ua_event
;
319 struct ust_app_ctx
*ua_ctx
;
320 struct ust_app_stream
*stream
, *stmp
;
321 struct ust_registry_session
*registry
;
325 DBG3("UST app deleting channel %s", ua_chan
->name
);
328 cds_list_for_each_entry_safe(stream
, stmp
, &ua_chan
->streams
.head
, list
) {
329 cds_list_del(&stream
->list
);
330 delete_ust_app_stream(sock
, stream
);
334 cds_lfht_for_each_entry(ua_chan
->ctx
->ht
, &iter
.iter
, ua_ctx
, node
.node
) {
335 ret
= lttng_ht_del(ua_chan
->ctx
, &iter
);
337 delete_ust_app_ctx(sock
, ua_ctx
);
339 lttng_ht_destroy(ua_chan
->ctx
);
342 cds_lfht_for_each_entry(ua_chan
->events
->ht
, &iter
.iter
, ua_event
,
344 ret
= lttng_ht_del(ua_chan
->events
, &iter
);
346 delete_ust_app_event(sock
, ua_event
);
348 lttng_ht_destroy(ua_chan
->events
);
350 /* Wipe and free registry from session registry. */
351 registry
= get_session_registry(ua_chan
->session
);
353 ust_registry_channel_del_free(registry
, ua_chan
->key
);
356 if (ua_chan
->obj
!= NULL
) {
357 /* Remove channel from application UST object descriptor. */
358 iter
.iter
.node
= &ua_chan
->ust_objd_node
.node
;
359 lttng_ht_del(app
->ust_objd
, &iter
);
360 ret
= ustctl_release_object(sock
, ua_chan
->obj
);
361 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
362 ERR("UST app sock %d release channel obj failed with ret %d",
365 lttng_fd_put(LTTNG_FD_APPS
, 1);
372 * Push metadata to consumer socket. The socket lock MUST be acquired.
374 * On success, return the len of metadata pushed or else a negative value.
376 ssize_t
ust_app_push_metadata(struct ust_registry_session
*registry
,
377 struct consumer_socket
*socket
, int send_zero_data
)
380 char *metadata_str
= NULL
;
386 /* Should never be 0 which is the initial state. */
387 assert(registry
->metadata_key
);
389 pthread_mutex_lock(®istry
->lock
);
391 offset
= registry
->metadata_len_sent
;
392 len
= registry
->metadata_len
- registry
->metadata_len_sent
;
394 DBG3("No metadata to push for metadata key %" PRIu64
,
395 registry
->metadata_key
);
397 if (send_zero_data
) {
398 DBG("No metadata to push");
404 /* Allocate only what we have to send. */
405 metadata_str
= zmalloc(len
);
407 PERROR("zmalloc ust app metadata string");
411 /* Copy what we haven't send out. */
412 memcpy(metadata_str
, registry
->metadata
+ offset
, len
);
413 registry
->metadata_len_sent
+= len
;
416 pthread_mutex_unlock(®istry
->lock
);
417 ret
= consumer_push_metadata(socket
, registry
->metadata_key
,
418 metadata_str
, len
, offset
);
429 pthread_mutex_unlock(®istry
->lock
);
436 * For a given application and session, push metadata to consumer. The session
437 * lock MUST be acquired here before calling this.
438 * Either sock or consumer is required : if sock is NULL, the default
439 * socket to send the metadata is retrieved from consumer, if sock
440 * is not NULL we use it to send the metadata.
442 * Return 0 on success else a negative error.
444 static int push_metadata(struct ust_registry_session
*registry
,
445 struct consumer_output
*consumer
)
449 struct consumer_socket
*socket
;
457 * Means that no metadata was assigned to the session. This can happens if
458 * no start has been done previously.
460 if (!registry
->metadata_key
) {
462 goto error_rcu_unlock
;
465 /* Get consumer socket to use to push the metadata.*/
466 socket
= consumer_find_socket_by_bitness(registry
->bits_per_long
,
470 goto error_rcu_unlock
;
474 * TODO: Currently, we hold the socket lock around sampling of the next
475 * metadata segment to ensure we send metadata over the consumer socket in
476 * the correct order. This makes the registry lock nest inside the socket
479 * Please note that this is a temporary measure: we should move this lock
480 * back into ust_consumer_push_metadata() when the consumer gets the
481 * ability to reorder the metadata it receives.
483 pthread_mutex_lock(socket
->lock
);
484 ret
= ust_app_push_metadata(registry
, socket
, 0);
485 pthread_mutex_unlock(socket
->lock
);
488 goto error_rcu_unlock
;
500 * Send to the consumer a close metadata command for the given session. Once
501 * done, the metadata channel is deleted and the session metadata pointer is
502 * nullified. The session lock MUST be acquired here unless the application is
503 * in the destroy path.
505 * Return 0 on success else a negative value.
507 static int close_metadata(struct ust_registry_session
*registry
,
508 struct consumer_output
*consumer
)
511 struct consumer_socket
*socket
;
518 if (!registry
->metadata_key
|| registry
->metadata_closed
) {
523 /* Get consumer socket to use to push the metadata.*/
524 socket
= consumer_find_socket_by_bitness(registry
->bits_per_long
,
531 ret
= consumer_close_metadata(socket
, registry
->metadata_key
);
536 /* Metadata successfully closed. Flag the registry. */
537 registry
->metadata_closed
= 1;
545 * Delete ust app session safely. RCU read lock must be held before calling
549 void delete_ust_app_session(int sock
, struct ust_app_session
*ua_sess
,
553 struct lttng_ht_iter iter
;
554 struct ust_app_channel
*ua_chan
;
555 struct ust_registry_session
*registry
;
559 registry
= get_session_registry(ua_sess
);
561 /* Push metadata for application before freeing the application. */
562 (void) push_metadata(registry
, ua_sess
->consumer
);
565 * Don't ask to close metadata for global per UID buffers. Close
566 * metadata only on destroy trace session in this case.
568 if (ua_sess
->buffer_type
!= LTTNG_BUFFER_PER_UID
) {
569 /* And ask to close it for this session registry. */
570 (void) close_metadata(registry
, ua_sess
->consumer
);
574 cds_lfht_for_each_entry(ua_sess
->channels
->ht
, &iter
.iter
, ua_chan
,
576 ret
= lttng_ht_del(ua_sess
->channels
, &iter
);
578 delete_ust_app_channel(sock
, ua_chan
, app
);
580 lttng_ht_destroy(ua_sess
->channels
);
582 /* In case of per PID, the registry is kept in the session. */
583 if (ua_sess
->buffer_type
== LTTNG_BUFFER_PER_PID
) {
584 struct buffer_reg_pid
*reg_pid
= buffer_reg_pid_find(ua_sess
->id
);
586 buffer_reg_pid_remove(reg_pid
);
587 buffer_reg_pid_destroy(reg_pid
);
591 if (ua_sess
->handle
!= -1) {
592 ret
= ustctl_release_handle(sock
, ua_sess
->handle
);
593 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
594 ERR("UST app sock %d release session handle failed with ret %d",
602 * Delete a traceable application structure from the global list. Never call
603 * this function outside of a call_rcu call.
606 void delete_ust_app(struct ust_app
*app
)
609 struct ust_app_session
*ua_sess
, *tmp_ua_sess
;
613 /* Delete ust app sessions info */
617 lttng_ht_destroy(app
->sessions
);
620 cds_list_for_each_entry_safe(ua_sess
, tmp_ua_sess
, &app
->teardown_head
,
622 /* Free every object in the session and the session. */
623 delete_ust_app_session(sock
, ua_sess
, app
);
625 lttng_ht_destroy(app
->ust_objd
);
628 * Wait until we have deleted the application from the sock hash table
629 * before closing this socket, otherwise an application could re-use the
630 * socket ID and race with the teardown, using the same hash table entry.
632 * It's OK to leave the close in call_rcu. We want it to stay unique for
633 * all RCU readers that could run concurrently with unregister app,
634 * therefore we _need_ to only close that socket after a grace period. So
635 * it should stay in this RCU callback.
637 * This close() is a very important step of the synchronization model so
638 * every modification to this function must be carefully reviewed.
644 lttng_fd_put(LTTNG_FD_APPS
, 1);
646 DBG2("UST app pid %d deleted", app
->pid
);
653 * URCU intermediate call to delete an UST app.
656 void delete_ust_app_rcu(struct rcu_head
*head
)
658 struct lttng_ht_node_ulong
*node
=
659 caa_container_of(head
, struct lttng_ht_node_ulong
, head
);
660 struct ust_app
*app
=
661 caa_container_of(node
, struct ust_app
, pid_n
);
663 DBG3("Call RCU deleting app PID %d", app
->pid
);
668 * Delete the session from the application ht and delete the data structure by
669 * freeing every object inside and releasing them.
671 static void destroy_app_session(struct ust_app
*app
,
672 struct ust_app_session
*ua_sess
)
675 struct lttng_ht_iter iter
;
680 iter
.iter
.node
= &ua_sess
->node
.node
;
681 ret
= lttng_ht_del(app
->sessions
, &iter
);
683 /* Already scheduled for teardown. */
687 /* Once deleted, free the data structure. */
688 delete_ust_app_session(app
->sock
, ua_sess
, app
);
695 * Alloc new UST app session.
698 struct ust_app_session
*alloc_ust_app_session(struct ust_app
*app
)
700 struct ust_app_session
*ua_sess
;
702 /* Init most of the default value by allocating and zeroing */
703 ua_sess
= zmalloc(sizeof(struct ust_app_session
));
704 if (ua_sess
== NULL
) {
709 ua_sess
->handle
= -1;
710 ua_sess
->channels
= lttng_ht_new(0, LTTNG_HT_TYPE_STRING
);
711 pthread_mutex_init(&ua_sess
->lock
, NULL
);
720 * Alloc new UST app channel.
723 struct ust_app_channel
*alloc_ust_app_channel(char *name
,
724 struct ust_app_session
*ua_sess
,
725 struct lttng_ust_channel_attr
*attr
)
727 struct ust_app_channel
*ua_chan
;
729 /* Init most of the default value by allocating and zeroing */
730 ua_chan
= zmalloc(sizeof(struct ust_app_channel
));
731 if (ua_chan
== NULL
) {
736 /* Setup channel name */
737 strncpy(ua_chan
->name
, name
, sizeof(ua_chan
->name
));
738 ua_chan
->name
[sizeof(ua_chan
->name
) - 1] = '\0';
740 ua_chan
->enabled
= 1;
741 ua_chan
->handle
= -1;
742 ua_chan
->session
= ua_sess
;
743 ua_chan
->key
= get_next_channel_key();
744 ua_chan
->ctx
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
745 ua_chan
->events
= lttng_ht_new(0, LTTNG_HT_TYPE_STRING
);
746 lttng_ht_node_init_str(&ua_chan
->node
, ua_chan
->name
);
748 CDS_INIT_LIST_HEAD(&ua_chan
->streams
.head
);
750 /* Copy attributes */
752 /* Translate from lttng_ust_channel to ustctl_consumer_channel_attr. */
753 ua_chan
->attr
.subbuf_size
= attr
->subbuf_size
;
754 ua_chan
->attr
.num_subbuf
= attr
->num_subbuf
;
755 ua_chan
->attr
.overwrite
= attr
->overwrite
;
756 ua_chan
->attr
.switch_timer_interval
= attr
->switch_timer_interval
;
757 ua_chan
->attr
.read_timer_interval
= attr
->read_timer_interval
;
758 ua_chan
->attr
.output
= attr
->output
;
760 /* By default, the channel is a per cpu channel. */
761 ua_chan
->attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
763 DBG3("UST app channel %s allocated", ua_chan
->name
);
772 * Allocate and initialize a UST app stream.
774 * Return newly allocated stream pointer or NULL on error.
776 struct ust_app_stream
*ust_app_alloc_stream(void)
778 struct ust_app_stream
*stream
= NULL
;
780 stream
= zmalloc(sizeof(*stream
));
781 if (stream
== NULL
) {
782 PERROR("zmalloc ust app stream");
786 /* Zero could be a valid value for a handle so flag it to -1. */
794 * Alloc new UST app event.
797 struct ust_app_event
*alloc_ust_app_event(char *name
,
798 struct lttng_ust_event
*attr
)
800 struct ust_app_event
*ua_event
;
802 /* Init most of the default value by allocating and zeroing */
803 ua_event
= zmalloc(sizeof(struct ust_app_event
));
804 if (ua_event
== NULL
) {
809 ua_event
->enabled
= 1;
810 strncpy(ua_event
->name
, name
, sizeof(ua_event
->name
));
811 ua_event
->name
[sizeof(ua_event
->name
) - 1] = '\0';
812 lttng_ht_node_init_str(&ua_event
->node
, ua_event
->name
);
814 /* Copy attributes */
816 memcpy(&ua_event
->attr
, attr
, sizeof(ua_event
->attr
));
819 DBG3("UST app event %s allocated", ua_event
->name
);
828 * Alloc new UST app context.
831 struct ust_app_ctx
*alloc_ust_app_ctx(struct lttng_ust_context
*uctx
)
833 struct ust_app_ctx
*ua_ctx
;
835 ua_ctx
= zmalloc(sizeof(struct ust_app_ctx
));
836 if (ua_ctx
== NULL
) {
841 memcpy(&ua_ctx
->ctx
, uctx
, sizeof(ua_ctx
->ctx
));
844 DBG3("UST app context %d allocated", ua_ctx
->ctx
.ctx
);
851 * Allocate a filter and copy the given original filter.
853 * Return allocated filter or NULL on error.
855 static struct lttng_ust_filter_bytecode
*alloc_copy_ust_app_filter(
856 struct lttng_ust_filter_bytecode
*orig_f
)
858 struct lttng_ust_filter_bytecode
*filter
= NULL
;
860 /* Copy filter bytecode */
861 filter
= zmalloc(sizeof(*filter
) + orig_f
->len
);
863 PERROR("zmalloc alloc ust app filter");
867 memcpy(filter
, orig_f
, sizeof(*filter
) + orig_f
->len
);
874 * Find an ust_app using the sock and return it. RCU read side lock must be
875 * held before calling this helper function.
878 struct ust_app
*find_app_by_sock(int sock
)
880 struct lttng_ht_node_ulong
*node
;
881 struct lttng_ht_iter iter
;
883 lttng_ht_lookup(ust_app_ht_by_sock
, (void *)((unsigned long) sock
), &iter
);
884 node
= lttng_ht_iter_get_node_ulong(&iter
);
886 DBG2("UST app find by sock %d not found", sock
);
890 return caa_container_of(node
, struct ust_app
, sock_n
);
897 * Find an ust_app using the notify sock and return it. RCU read side lock must
898 * be held before calling this helper function.
900 static struct ust_app
*find_app_by_notify_sock(int sock
)
902 struct lttng_ht_node_ulong
*node
;
903 struct lttng_ht_iter iter
;
905 lttng_ht_lookup(ust_app_ht_by_notify_sock
, (void *)((unsigned long) sock
),
907 node
= lttng_ht_iter_get_node_ulong(&iter
);
909 DBG2("UST app find by notify sock %d not found", sock
);
913 return caa_container_of(node
, struct ust_app
, notify_sock_n
);
920 * Lookup for an ust app event based on event name, filter bytecode and the
923 * Return an ust_app_event object or NULL on error.
925 static struct ust_app_event
*find_ust_app_event(struct lttng_ht
*ht
,
926 char *name
, struct lttng_ust_filter_bytecode
*filter
, int loglevel
)
928 struct lttng_ht_iter iter
;
929 struct lttng_ht_node_str
*node
;
930 struct ust_app_event
*event
= NULL
;
931 struct ust_app_ht_key key
;
936 /* Setup key for event lookup. */
939 key
.loglevel
= loglevel
;
941 /* Lookup using the event name as hash and a custom match fct. */
942 cds_lfht_lookup(ht
->ht
, ht
->hash_fct((void *) name
, lttng_ht_seed
),
943 ht_match_ust_app_event
, &key
, &iter
.iter
);
944 node
= lttng_ht_iter_get_node_str(&iter
);
949 event
= caa_container_of(node
, struct ust_app_event
, node
);
956 * Create the channel context on the tracer.
958 * Called with UST app session lock held.
961 int create_ust_channel_context(struct ust_app_channel
*ua_chan
,
962 struct ust_app_ctx
*ua_ctx
, struct ust_app
*app
)
966 health_code_update();
968 ret
= ustctl_add_context(app
->sock
, &ua_ctx
->ctx
,
969 ua_chan
->obj
, &ua_ctx
->obj
);
971 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
972 ERR("UST app create channel context failed for app (pid: %d) "
973 "with ret %d", app
->pid
, ret
);
975 DBG3("UST app disable event failed. Application is dead.");
980 ua_ctx
->handle
= ua_ctx
->obj
->handle
;
982 DBG2("UST app context handle %d created successfully for channel %s",
983 ua_ctx
->handle
, ua_chan
->name
);
986 health_code_update();
991 * Set the filter on the tracer.
994 int set_ust_event_filter(struct ust_app_event
*ua_event
,
999 health_code_update();
1001 if (!ua_event
->filter
) {
1006 ret
= ustctl_set_filter(app
->sock
, ua_event
->filter
,
1009 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1010 ERR("UST app event %s filter failed for app (pid: %d) "
1011 "with ret %d", ua_event
->attr
.name
, app
->pid
, ret
);
1013 DBG3("UST app filter event failed. Application is dead.");
1018 DBG2("UST filter set successfully for event %s", ua_event
->name
);
1021 health_code_update();
1026 * Disable the specified event on to UST tracer for the UST session.
1028 static int disable_ust_event(struct ust_app
*app
,
1029 struct ust_app_session
*ua_sess
, struct ust_app_event
*ua_event
)
1033 health_code_update();
1035 ret
= ustctl_disable(app
->sock
, ua_event
->obj
);
1037 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1038 ERR("UST app event %s disable failed for app (pid: %d) "
1039 "and session handle %d with ret %d",
1040 ua_event
->attr
.name
, app
->pid
, ua_sess
->handle
, ret
);
1042 DBG3("UST app disable event failed. Application is dead.");
1047 DBG2("UST app event %s disabled successfully for app (pid: %d)",
1048 ua_event
->attr
.name
, app
->pid
);
1051 health_code_update();
1056 * Disable the specified channel on to UST tracer for the UST session.
1058 static int disable_ust_channel(struct ust_app
*app
,
1059 struct ust_app_session
*ua_sess
, struct ust_app_channel
*ua_chan
)
1063 health_code_update();
1065 ret
= ustctl_disable(app
->sock
, ua_chan
->obj
);
1067 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1068 ERR("UST app channel %s disable failed for app (pid: %d) "
1069 "and session handle %d with ret %d",
1070 ua_chan
->name
, app
->pid
, ua_sess
->handle
, ret
);
1072 DBG3("UST app disable channel failed. Application is dead.");
1077 DBG2("UST app channel %s disabled successfully for app (pid: %d)",
1078 ua_chan
->name
, app
->pid
);
1081 health_code_update();
1086 * Enable the specified channel on to UST tracer for the UST session.
1088 static int enable_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_enable(app
->sock
, ua_chan
->obj
);
1097 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1098 ERR("UST app channel %s enable 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 enable channel failed. Application is dead.");
1107 ua_chan
->enabled
= 1;
1109 DBG2("UST app channel %s enabled successfully for app (pid: %d)",
1110 ua_chan
->name
, app
->pid
);
1113 health_code_update();
1118 * Enable the specified event on to UST tracer for the UST session.
1120 static int enable_ust_event(struct ust_app
*app
,
1121 struct ust_app_session
*ua_sess
, struct ust_app_event
*ua_event
)
1125 health_code_update();
1127 ret
= ustctl_enable(app
->sock
, ua_event
->obj
);
1129 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1130 ERR("UST app event %s enable failed for app (pid: %d) "
1131 "and session handle %d with ret %d",
1132 ua_event
->attr
.name
, app
->pid
, ua_sess
->handle
, ret
);
1134 DBG3("UST app enable event failed. Application is dead.");
1139 DBG2("UST app event %s enabled successfully for app (pid: %d)",
1140 ua_event
->attr
.name
, app
->pid
);
1143 health_code_update();
1148 * Send channel and stream buffer to application.
1150 * Return 0 on success. On error, a negative value is returned.
1152 static int send_channel_pid_to_ust(struct ust_app
*app
,
1153 struct ust_app_session
*ua_sess
, struct ust_app_channel
*ua_chan
)
1156 struct ust_app_stream
*stream
, *stmp
;
1162 health_code_update();
1164 DBG("UST app sending channel %s to UST app sock %d", ua_chan
->name
,
1167 /* Send channel to the application. */
1168 ret
= ust_consumer_send_channel_to_ust(app
, ua_sess
, ua_chan
);
1173 health_code_update();
1175 /* Send all streams to application. */
1176 cds_list_for_each_entry_safe(stream
, stmp
, &ua_chan
->streams
.head
, list
) {
1177 ret
= ust_consumer_send_stream_to_ust(app
, ua_chan
, stream
);
1181 /* We don't need the stream anymore once sent to the tracer. */
1182 cds_list_del(&stream
->list
);
1183 delete_ust_app_stream(-1, stream
);
1185 /* Flag the channel that it is sent to the application. */
1186 ua_chan
->is_sent
= 1;
1189 health_code_update();
1194 * Create the specified event onto the UST tracer for a UST session.
1196 * Should be called with session mutex held.
1199 int create_ust_event(struct ust_app
*app
, struct ust_app_session
*ua_sess
,
1200 struct ust_app_channel
*ua_chan
, struct ust_app_event
*ua_event
)
1204 health_code_update();
1206 /* Create UST event on tracer */
1207 ret
= ustctl_create_event(app
->sock
, &ua_event
->attr
, ua_chan
->obj
,
1210 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1211 ERR("Error ustctl create event %s for app pid: %d with ret %d",
1212 ua_event
->attr
.name
, app
->pid
, ret
);
1214 DBG3("UST app create event failed. Application is dead.");
1219 ua_event
->handle
= ua_event
->obj
->handle
;
1221 DBG2("UST app event %s created successfully for pid:%d",
1222 ua_event
->attr
.name
, app
->pid
);
1224 health_code_update();
1226 /* Set filter if one is present. */
1227 if (ua_event
->filter
) {
1228 ret
= set_ust_event_filter(ua_event
, app
);
1234 /* If event not enabled, disable it on the tracer */
1235 if (ua_event
->enabled
== 0) {
1236 ret
= disable_ust_event(app
, ua_sess
, ua_event
);
1239 * If we hit an EPERM, something is wrong with our disable call. If
1240 * we get an EEXIST, there is a problem on the tracer side since we
1244 case -LTTNG_UST_ERR_PERM
:
1245 /* Code flow problem */
1247 case -LTTNG_UST_ERR_EXIST
:
1248 /* It's OK for our use case. */
1259 health_code_update();
1264 * Copy data between an UST app event and a LTT event.
1266 static void shadow_copy_event(struct ust_app_event
*ua_event
,
1267 struct ltt_ust_event
*uevent
)
1269 strncpy(ua_event
->name
, uevent
->attr
.name
, sizeof(ua_event
->name
));
1270 ua_event
->name
[sizeof(ua_event
->name
) - 1] = '\0';
1272 ua_event
->enabled
= uevent
->enabled
;
1274 /* Copy event attributes */
1275 memcpy(&ua_event
->attr
, &uevent
->attr
, sizeof(ua_event
->attr
));
1277 /* Copy filter bytecode */
1278 if (uevent
->filter
) {
1279 ua_event
->filter
= alloc_copy_ust_app_filter(uevent
->filter
);
1280 /* Filter might be NULL here in case of ENONEM. */
1285 * Copy data between an UST app channel and a LTT channel.
1287 static void shadow_copy_channel(struct ust_app_channel
*ua_chan
,
1288 struct ltt_ust_channel
*uchan
)
1290 struct lttng_ht_iter iter
;
1291 struct ltt_ust_event
*uevent
;
1292 struct ltt_ust_context
*uctx
;
1293 struct ust_app_event
*ua_event
;
1294 struct ust_app_ctx
*ua_ctx
;
1296 DBG2("UST app shadow copy of channel %s started", ua_chan
->name
);
1298 strncpy(ua_chan
->name
, uchan
->name
, sizeof(ua_chan
->name
));
1299 ua_chan
->name
[sizeof(ua_chan
->name
) - 1] = '\0';
1301 ua_chan
->tracefile_size
= uchan
->tracefile_size
;
1302 ua_chan
->tracefile_count
= uchan
->tracefile_count
;
1304 /* Copy event attributes since the layout is different. */
1305 ua_chan
->attr
.subbuf_size
= uchan
->attr
.subbuf_size
;
1306 ua_chan
->attr
.num_subbuf
= uchan
->attr
.num_subbuf
;
1307 ua_chan
->attr
.overwrite
= uchan
->attr
.overwrite
;
1308 ua_chan
->attr
.switch_timer_interval
= uchan
->attr
.switch_timer_interval
;
1309 ua_chan
->attr
.read_timer_interval
= uchan
->attr
.read_timer_interval
;
1310 ua_chan
->attr
.output
= uchan
->attr
.output
;
1312 * Note that the attribute channel type is not set since the channel on the
1313 * tracing registry side does not have this information.
1316 ua_chan
->enabled
= uchan
->enabled
;
1317 ua_chan
->tracing_channel_id
= uchan
->id
;
1319 cds_lfht_for_each_entry(uchan
->ctx
->ht
, &iter
.iter
, uctx
, node
.node
) {
1320 ua_ctx
= alloc_ust_app_ctx(&uctx
->ctx
);
1321 if (ua_ctx
== NULL
) {
1324 lttng_ht_node_init_ulong(&ua_ctx
->node
,
1325 (unsigned long) ua_ctx
->ctx
.ctx
);
1326 lttng_ht_add_unique_ulong(ua_chan
->ctx
, &ua_ctx
->node
);
1329 /* Copy all events from ltt ust channel to ust app channel */
1330 cds_lfht_for_each_entry(uchan
->events
->ht
, &iter
.iter
, uevent
, node
.node
) {
1331 ua_event
= find_ust_app_event(ua_chan
->events
, uevent
->attr
.name
,
1332 uevent
->filter
, uevent
->attr
.loglevel
);
1333 if (ua_event
== NULL
) {
1334 DBG2("UST event %s not found on shadow copy channel",
1336 ua_event
= alloc_ust_app_event(uevent
->attr
.name
, &uevent
->attr
);
1337 if (ua_event
== NULL
) {
1340 shadow_copy_event(ua_event
, uevent
);
1341 add_unique_ust_app_event(ua_chan
, ua_event
);
1345 DBG3("UST app shadow copy of channel %s done", ua_chan
->name
);
1349 * Copy data between a UST app session and a regular LTT session.
1351 static void shadow_copy_session(struct ust_app_session
*ua_sess
,
1352 struct ltt_ust_session
*usess
, struct ust_app
*app
)
1354 struct lttng_ht_node_str
*ua_chan_node
;
1355 struct lttng_ht_iter iter
;
1356 struct ltt_ust_channel
*uchan
;
1357 struct ust_app_channel
*ua_chan
;
1359 struct tm
*timeinfo
;
1363 /* Get date and time for unique app path */
1365 timeinfo
= localtime(&rawtime
);
1366 strftime(datetime
, sizeof(datetime
), "%Y%m%d-%H%M%S", timeinfo
);
1368 DBG2("Shadow copy of session handle %d", ua_sess
->handle
);
1370 ua_sess
->tracing_id
= usess
->id
;
1371 ua_sess
->id
= get_next_session_id();
1372 ua_sess
->uid
= app
->uid
;
1373 ua_sess
->gid
= app
->gid
;
1374 ua_sess
->euid
= usess
->uid
;
1375 ua_sess
->egid
= usess
->gid
;
1376 ua_sess
->buffer_type
= usess
->buffer_type
;
1377 ua_sess
->bits_per_long
= app
->bits_per_long
;
1378 /* There is only one consumer object per session possible. */
1379 ua_sess
->consumer
= usess
->consumer
;
1381 switch (ua_sess
->buffer_type
) {
1382 case LTTNG_BUFFER_PER_PID
:
1383 ret
= snprintf(ua_sess
->path
, sizeof(ua_sess
->path
),
1384 DEFAULT_UST_TRACE_PID_PATH
"/%s-%d-%s/", app
->name
, app
->pid
,
1387 case LTTNG_BUFFER_PER_UID
:
1388 ret
= snprintf(ua_sess
->path
, sizeof(ua_sess
->path
),
1389 DEFAULT_UST_TRACE_UID_PATH
, ua_sess
->uid
, app
->bits_per_long
);
1396 PERROR("asprintf UST shadow copy session");
1401 /* Iterate over all channels in global domain. */
1402 cds_lfht_for_each_entry(usess
->domain_global
.channels
->ht
, &iter
.iter
,
1404 struct lttng_ht_iter uiter
;
1406 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
1407 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
1408 if (ua_chan_node
!= NULL
) {
1409 /* Session exist. Contiuing. */
1413 DBG2("Channel %s not found on shadow session copy, creating it",
1415 ua_chan
= alloc_ust_app_channel(uchan
->name
, ua_sess
, &uchan
->attr
);
1416 if (ua_chan
== NULL
) {
1417 /* malloc failed FIXME: Might want to do handle ENOMEM .. */
1420 shadow_copy_channel(ua_chan
, uchan
);
1422 * The concept of metadata channel does not exist on the tracing
1423 * registry side of the session daemon so this can only be a per CPU
1424 * channel and not metadata.
1426 ua_chan
->attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1428 lttng_ht_add_unique_str(ua_sess
->channels
, &ua_chan
->node
);
1436 * Lookup sesison wrapper.
1439 void __lookup_session_by_app(struct ltt_ust_session
*usess
,
1440 struct ust_app
*app
, struct lttng_ht_iter
*iter
)
1442 /* Get right UST app session from app */
1443 lttng_ht_lookup(app
->sessions
, (void *)((unsigned long) usess
->id
), iter
);
1447 * Return ust app session from the app session hashtable using the UST session
1450 static struct ust_app_session
*lookup_session_by_app(
1451 struct ltt_ust_session
*usess
, struct ust_app
*app
)
1453 struct lttng_ht_iter iter
;
1454 struct lttng_ht_node_ulong
*node
;
1456 __lookup_session_by_app(usess
, app
, &iter
);
1457 node
= lttng_ht_iter_get_node_ulong(&iter
);
1462 return caa_container_of(node
, struct ust_app_session
, node
);
1469 * Setup buffer registry per PID for the given session and application. If none
1470 * is found, a new one is created, added to the global registry and
1471 * initialized. If regp is valid, it's set with the newly created object.
1473 * Return 0 on success or else a negative value.
1475 static int setup_buffer_reg_pid(struct ust_app_session
*ua_sess
,
1476 struct ust_app
*app
, struct buffer_reg_pid
**regp
)
1479 struct buffer_reg_pid
*reg_pid
;
1486 reg_pid
= buffer_reg_pid_find(ua_sess
->id
);
1489 * This is the create channel path meaning that if there is NO
1490 * registry available, we have to create one for this session.
1492 ret
= buffer_reg_pid_create(ua_sess
->id
, ®_pid
);
1496 buffer_reg_pid_add(reg_pid
);
1501 /* Initialize registry. */
1502 ret
= ust_registry_session_init(®_pid
->registry
->reg
.ust
, app
,
1503 app
->bits_per_long
, app
->uint8_t_alignment
,
1504 app
->uint16_t_alignment
, app
->uint32_t_alignment
,
1505 app
->uint64_t_alignment
, app
->long_alignment
,
1506 app
->byte_order
, app
->version
.major
,
1507 app
->version
.minor
);
1512 DBG3("UST app buffer registry per PID created successfully");
1524 * Setup buffer registry per UID for the given session and application. If none
1525 * is found, a new one is created, added to the global registry and
1526 * initialized. If regp is valid, it's set with the newly created object.
1528 * Return 0 on success or else a negative value.
1530 static int setup_buffer_reg_uid(struct ltt_ust_session
*usess
,
1531 struct ust_app
*app
, struct buffer_reg_uid
**regp
)
1534 struct buffer_reg_uid
*reg_uid
;
1541 reg_uid
= buffer_reg_uid_find(usess
->id
, app
->bits_per_long
, app
->uid
);
1544 * This is the create channel path meaning that if there is NO
1545 * registry available, we have to create one for this session.
1547 ret
= buffer_reg_uid_create(usess
->id
, app
->bits_per_long
, app
->uid
,
1548 LTTNG_DOMAIN_UST
, ®_uid
);
1552 buffer_reg_uid_add(reg_uid
);
1557 /* Initialize registry. */
1558 ret
= ust_registry_session_init(®_uid
->registry
->reg
.ust
, NULL
,
1559 app
->bits_per_long
, app
->uint8_t_alignment
,
1560 app
->uint16_t_alignment
, app
->uint32_t_alignment
,
1561 app
->uint64_t_alignment
, app
->long_alignment
,
1562 app
->byte_order
, app
->version
.major
,
1563 app
->version
.minor
);
1567 /* Add node to teardown list of the session. */
1568 cds_list_add(®_uid
->lnode
, &usess
->buffer_reg_uid_list
);
1570 DBG3("UST app buffer registry per UID created successfully");
1582 * Create a session on the tracer side for the given app.
1584 * On success, ua_sess_ptr is populated with the session pointer or else left
1585 * untouched. If the session was created, is_created is set to 1. On error,
1586 * it's left untouched. Note that ua_sess_ptr is mandatory but is_created can
1589 * Returns 0 on success or else a negative code which is either -ENOMEM or
1590 * -ENOTCONN which is the default code if the ustctl_create_session fails.
1592 static int create_ust_app_session(struct ltt_ust_session
*usess
,
1593 struct ust_app
*app
, struct ust_app_session
**ua_sess_ptr
,
1596 int ret
, created
= 0;
1597 struct ust_app_session
*ua_sess
;
1601 assert(ua_sess_ptr
);
1603 health_code_update();
1605 ua_sess
= lookup_session_by_app(usess
, app
);
1606 if (ua_sess
== NULL
) {
1607 DBG2("UST app pid: %d session id %d not found, creating it",
1608 app
->pid
, usess
->id
);
1609 ua_sess
= alloc_ust_app_session(app
);
1610 if (ua_sess
== NULL
) {
1611 /* Only malloc can failed so something is really wrong */
1615 shadow_copy_session(ua_sess
, usess
, app
);
1619 switch (usess
->buffer_type
) {
1620 case LTTNG_BUFFER_PER_PID
:
1621 /* Init local registry. */
1622 ret
= setup_buffer_reg_pid(ua_sess
, app
, NULL
);
1627 case LTTNG_BUFFER_PER_UID
:
1628 /* Look for a global registry. If none exists, create one. */
1629 ret
= setup_buffer_reg_uid(usess
, app
, NULL
);
1640 health_code_update();
1642 if (ua_sess
->handle
== -1) {
1643 ret
= ustctl_create_session(app
->sock
);
1645 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
1646 ERR("Creating session for app pid %d with ret %d",
1649 DBG("UST app creating session failed. Application is dead");
1651 delete_ust_app_session(-1, ua_sess
, app
);
1652 if (ret
!= -ENOMEM
) {
1654 * Tracer is probably gone or got an internal error so let's
1655 * behave like it will soon unregister or not usable.
1662 ua_sess
->handle
= ret
;
1664 /* Add ust app session to app's HT */
1665 lttng_ht_node_init_ulong(&ua_sess
->node
,
1666 (unsigned long) ua_sess
->tracing_id
);
1667 lttng_ht_add_unique_ulong(app
->sessions
, &ua_sess
->node
);
1669 DBG2("UST app session created successfully with handle %d", ret
);
1672 *ua_sess_ptr
= ua_sess
;
1674 *is_created
= created
;
1677 /* Everything went well. */
1681 health_code_update();
1686 * Create a context for the channel on the tracer.
1688 * Called with UST app session lock held and a RCU read side lock.
1691 int create_ust_app_channel_context(struct ust_app_session
*ua_sess
,
1692 struct ust_app_channel
*ua_chan
, struct lttng_ust_context
*uctx
,
1693 struct ust_app
*app
)
1696 struct lttng_ht_iter iter
;
1697 struct lttng_ht_node_ulong
*node
;
1698 struct ust_app_ctx
*ua_ctx
;
1700 DBG2("UST app adding context to channel %s", ua_chan
->name
);
1702 lttng_ht_lookup(ua_chan
->ctx
, (void *)((unsigned long)uctx
->ctx
), &iter
);
1703 node
= lttng_ht_iter_get_node_ulong(&iter
);
1709 ua_ctx
= alloc_ust_app_ctx(uctx
);
1710 if (ua_ctx
== NULL
) {
1716 lttng_ht_node_init_ulong(&ua_ctx
->node
, (unsigned long) ua_ctx
->ctx
.ctx
);
1717 lttng_ht_add_unique_ulong(ua_chan
->ctx
, &ua_ctx
->node
);
1719 ret
= create_ust_channel_context(ua_chan
, ua_ctx
, app
);
1729 * Enable on the tracer side a ust app event for the session and channel.
1731 * Called with UST app session lock held.
1734 int enable_ust_app_event(struct ust_app_session
*ua_sess
,
1735 struct ust_app_event
*ua_event
, struct ust_app
*app
)
1739 ret
= enable_ust_event(app
, ua_sess
, ua_event
);
1744 ua_event
->enabled
= 1;
1751 * Disable on the tracer side a ust app event for the session and channel.
1753 static int disable_ust_app_event(struct ust_app_session
*ua_sess
,
1754 struct ust_app_event
*ua_event
, struct ust_app
*app
)
1758 ret
= disable_ust_event(app
, ua_sess
, ua_event
);
1763 ua_event
->enabled
= 0;
1770 * Lookup ust app channel for session and disable it on the tracer side.
1773 int disable_ust_app_channel(struct ust_app_session
*ua_sess
,
1774 struct ust_app_channel
*ua_chan
, struct ust_app
*app
)
1778 ret
= disable_ust_channel(app
, ua_sess
, ua_chan
);
1783 ua_chan
->enabled
= 0;
1790 * Lookup ust app channel for session and enable it on the tracer side. This
1791 * MUST be called with a RCU read side lock acquired.
1793 static int enable_ust_app_channel(struct ust_app_session
*ua_sess
,
1794 struct ltt_ust_channel
*uchan
, struct ust_app
*app
)
1797 struct lttng_ht_iter iter
;
1798 struct lttng_ht_node_str
*ua_chan_node
;
1799 struct ust_app_channel
*ua_chan
;
1801 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &iter
);
1802 ua_chan_node
= lttng_ht_iter_get_node_str(&iter
);
1803 if (ua_chan_node
== NULL
) {
1804 DBG2("Unable to find channel %s in ust session id %u",
1805 uchan
->name
, ua_sess
->tracing_id
);
1809 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
1811 ret
= enable_ust_channel(app
, ua_sess
, ua_chan
);
1821 * Ask the consumer to create a channel and get it if successful.
1823 * Return 0 on success or else a negative value.
1825 static int do_consumer_create_channel(struct ltt_ust_session
*usess
,
1826 struct ust_app_session
*ua_sess
, struct ust_app_channel
*ua_chan
,
1827 int bitness
, struct ust_registry_session
*registry
)
1830 unsigned int nb_fd
= 0;
1831 struct consumer_socket
*socket
;
1839 health_code_update();
1841 /* Get the right consumer socket for the application. */
1842 socket
= consumer_find_socket_by_bitness(bitness
, usess
->consumer
);
1848 health_code_update();
1850 /* Need one fd for the channel. */
1851 ret
= lttng_fd_get(LTTNG_FD_APPS
, 1);
1853 ERR("Exhausted number of available FD upon create channel");
1858 * Ask consumer to create channel. The consumer will return the number of
1859 * stream we have to expect.
1861 ret
= ust_consumer_ask_channel(ua_sess
, ua_chan
, usess
->consumer
, socket
,
1868 * Compute the number of fd needed before receiving them. It must be 2 per
1869 * stream (2 being the default value here).
1871 nb_fd
= DEFAULT_UST_STREAM_FD_NUM
* ua_chan
->expected_stream_count
;
1873 /* Reserve the amount of file descriptor we need. */
1874 ret
= lttng_fd_get(LTTNG_FD_APPS
, nb_fd
);
1876 ERR("Exhausted number of available FD upon create channel");
1877 goto error_fd_get_stream
;
1880 health_code_update();
1883 * Now get the channel from the consumer. This call wil populate the stream
1884 * list of that channel and set the ust objects.
1886 ret
= ust_consumer_get_channel(socket
, ua_chan
);
1895 lttng_fd_put(LTTNG_FD_APPS
, nb_fd
);
1896 error_fd_get_stream
:
1898 * Initiate a destroy channel on the consumer since we had an error
1899 * handling it on our side. The return value is of no importance since we
1900 * already have a ret value set by the previous error that we need to
1903 (void) ust_consumer_destroy_channel(socket
, ua_chan
);
1905 lttng_fd_put(LTTNG_FD_APPS
, 1);
1907 health_code_update();
1913 * Duplicate the ust data object of the ust app stream and save it in the
1914 * buffer registry stream.
1916 * Return 0 on success or else a negative value.
1918 static int duplicate_stream_object(struct buffer_reg_stream
*reg_stream
,
1919 struct ust_app_stream
*stream
)
1926 /* Reserve the amount of file descriptor we need. */
1927 ret
= lttng_fd_get(LTTNG_FD_APPS
, 2);
1929 ERR("Exhausted number of available FD upon duplicate stream");
1933 /* Duplicate object for stream once the original is in the registry. */
1934 ret
= ustctl_duplicate_ust_object_data(&stream
->obj
,
1935 reg_stream
->obj
.ust
);
1937 ERR("Duplicate stream obj from %p to %p failed with ret %d",
1938 reg_stream
->obj
.ust
, stream
->obj
, ret
);
1939 lttng_fd_put(LTTNG_FD_APPS
, 2);
1942 stream
->handle
= stream
->obj
->handle
;
1949 * Duplicate the ust data object of the ust app. channel and save it in the
1950 * buffer registry channel.
1952 * Return 0 on success or else a negative value.
1954 static int duplicate_channel_object(struct buffer_reg_channel
*reg_chan
,
1955 struct ust_app_channel
*ua_chan
)
1962 /* Need two fds for the channel. */
1963 ret
= lttng_fd_get(LTTNG_FD_APPS
, 1);
1965 ERR("Exhausted number of available FD upon duplicate channel");
1969 /* Duplicate object for stream once the original is in the registry. */
1970 ret
= ustctl_duplicate_ust_object_data(&ua_chan
->obj
, reg_chan
->obj
.ust
);
1972 ERR("Duplicate channel obj from %p to %p failed with ret: %d",
1973 reg_chan
->obj
.ust
, ua_chan
->obj
, ret
);
1976 ua_chan
->handle
= ua_chan
->obj
->handle
;
1981 lttng_fd_put(LTTNG_FD_APPS
, 1);
1987 * For a given channel buffer registry, setup all streams of the given ust
1988 * application channel.
1990 * Return 0 on success or else a negative value.
1992 static int setup_buffer_reg_streams(struct buffer_reg_channel
*reg_chan
,
1993 struct ust_app_channel
*ua_chan
)
1996 struct ust_app_stream
*stream
, *stmp
;
2001 DBG2("UST app setup buffer registry stream");
2003 /* Send all streams to application. */
2004 cds_list_for_each_entry_safe(stream
, stmp
, &ua_chan
->streams
.head
, list
) {
2005 struct buffer_reg_stream
*reg_stream
;
2007 ret
= buffer_reg_stream_create(®_stream
);
2013 * Keep original pointer and nullify it in the stream so the delete
2014 * stream call does not release the object.
2016 reg_stream
->obj
.ust
= stream
->obj
;
2018 buffer_reg_stream_add(reg_stream
, reg_chan
);
2020 /* We don't need the streams anymore. */
2021 cds_list_del(&stream
->list
);
2022 delete_ust_app_stream(-1, stream
);
2030 * Create a buffer registry channel for the given session registry and
2031 * application channel object. If regp pointer is valid, it's set with the
2032 * created object. Important, the created object is NOT added to the session
2033 * registry hash table.
2035 * Return 0 on success else a negative value.
2037 static int create_buffer_reg_channel(struct buffer_reg_session
*reg_sess
,
2038 struct ust_app_channel
*ua_chan
, struct buffer_reg_channel
**regp
)
2041 struct buffer_reg_channel
*reg_chan
= NULL
;
2046 DBG2("UST app creating buffer registry channel for %s", ua_chan
->name
);
2048 /* Create buffer registry channel. */
2049 ret
= buffer_reg_channel_create(ua_chan
->tracing_channel_id
, ®_chan
);
2054 reg_chan
->consumer_key
= ua_chan
->key
;
2056 /* Create and add a channel registry to session. */
2057 ret
= ust_registry_channel_add(reg_sess
->reg
.ust
,
2058 ua_chan
->tracing_channel_id
);
2062 buffer_reg_channel_add(reg_sess
, reg_chan
);
2071 /* Safe because the registry channel object was not added to any HT. */
2072 buffer_reg_channel_destroy(reg_chan
, LTTNG_DOMAIN_UST
);
2078 * Setup buffer registry channel for the given session registry and application
2079 * channel object. If regp pointer is valid, it's set with the created object.
2081 * Return 0 on success else a negative value.
2083 static int setup_buffer_reg_channel(struct buffer_reg_session
*reg_sess
,
2084 struct ust_app_channel
*ua_chan
, struct buffer_reg_channel
*reg_chan
)
2091 assert(ua_chan
->obj
);
2093 DBG2("UST app setup buffer registry channel for %s", ua_chan
->name
);
2095 /* Setup all streams for the registry. */
2096 ret
= setup_buffer_reg_streams(reg_chan
, ua_chan
);
2101 reg_chan
->obj
.ust
= ua_chan
->obj
;
2102 ua_chan
->obj
= NULL
;
2107 buffer_reg_channel_remove(reg_sess
, reg_chan
);
2108 buffer_reg_channel_destroy(reg_chan
, LTTNG_DOMAIN_UST
);
2113 * Send buffer registry channel to the application.
2115 * Return 0 on success else a negative value.
2117 static int send_channel_uid_to_ust(struct buffer_reg_channel
*reg_chan
,
2118 struct ust_app
*app
, struct ust_app_session
*ua_sess
,
2119 struct ust_app_channel
*ua_chan
)
2122 struct buffer_reg_stream
*reg_stream
;
2129 DBG("UST app sending buffer registry channel to ust sock %d", app
->sock
);
2131 ret
= duplicate_channel_object(reg_chan
, ua_chan
);
2136 /* Send channel to the application. */
2137 ret
= ust_consumer_send_channel_to_ust(app
, ua_sess
, ua_chan
);
2142 health_code_update();
2144 /* Send all streams to application. */
2145 pthread_mutex_lock(®_chan
->stream_list_lock
);
2146 cds_list_for_each_entry(reg_stream
, ®_chan
->streams
, lnode
) {
2147 struct ust_app_stream stream
;
2149 ret
= duplicate_stream_object(reg_stream
, &stream
);
2151 goto error_stream_unlock
;
2154 ret
= ust_consumer_send_stream_to_ust(app
, ua_chan
, &stream
);
2156 goto error_stream_unlock
;
2160 * The return value is not important here. This function will output an
2163 (void) release_ust_app_stream(-1, &stream
);
2165 ua_chan
->is_sent
= 1;
2167 error_stream_unlock
:
2168 pthread_mutex_unlock(®_chan
->stream_list_lock
);
2174 * Create and send to the application the created buffers with per UID buffers.
2176 * Return 0 on success else a negative value.
2178 static int create_channel_per_uid(struct ust_app
*app
,
2179 struct ltt_ust_session
*usess
, struct ust_app_session
*ua_sess
,
2180 struct ust_app_channel
*ua_chan
)
2183 struct buffer_reg_uid
*reg_uid
;
2184 struct buffer_reg_channel
*reg_chan
;
2191 DBG("UST app creating channel %s with per UID buffers", ua_chan
->name
);
2193 reg_uid
= buffer_reg_uid_find(usess
->id
, app
->bits_per_long
, app
->uid
);
2195 * The session creation handles the creation of this global registry
2196 * object. If none can be find, there is a code flow problem or a
2201 reg_chan
= buffer_reg_channel_find(ua_chan
->tracing_channel_id
,
2204 /* Create the buffer registry channel object. */
2205 ret
= create_buffer_reg_channel(reg_uid
->registry
, ua_chan
, ®_chan
);
2212 * Create the buffers on the consumer side. This call populates the
2213 * ust app channel object with all streams and data object.
2215 ret
= do_consumer_create_channel(usess
, ua_sess
, ua_chan
,
2216 app
->bits_per_long
, reg_uid
->registry
->reg
.ust
);
2222 * Setup the streams and add it to the session registry.
2224 ret
= setup_buffer_reg_channel(reg_uid
->registry
, ua_chan
, reg_chan
);
2231 /* Send buffers to the application. */
2232 ret
= send_channel_uid_to_ust(reg_chan
, app
, ua_sess
, ua_chan
);
2242 * Create and send to the application the created buffers with per PID buffers.
2244 * Return 0 on success else a negative value.
2246 static int create_channel_per_pid(struct ust_app
*app
,
2247 struct ltt_ust_session
*usess
, struct ust_app_session
*ua_sess
,
2248 struct ust_app_channel
*ua_chan
)
2251 struct ust_registry_session
*registry
;
2258 DBG("UST app creating channel %s with per PID buffers", ua_chan
->name
);
2262 registry
= get_session_registry(ua_sess
);
2265 /* Create and add a new channel registry to session. */
2266 ret
= ust_registry_channel_add(registry
, ua_chan
->key
);
2271 /* Create and get channel on the consumer side. */
2272 ret
= do_consumer_create_channel(usess
, ua_sess
, ua_chan
,
2273 app
->bits_per_long
, registry
);
2278 ret
= send_channel_pid_to_ust(app
, ua_sess
, ua_chan
);
2289 * From an already allocated ust app channel, create the channel buffers if
2290 * need and send it to the application. This MUST be called with a RCU read
2291 * side lock acquired.
2293 * Return 0 on success or else a negative value.
2295 static int do_create_channel(struct ust_app
*app
,
2296 struct ltt_ust_session
*usess
, struct ust_app_session
*ua_sess
,
2297 struct ust_app_channel
*ua_chan
)
2306 /* Handle buffer type before sending the channel to the application. */
2307 switch (usess
->buffer_type
) {
2308 case LTTNG_BUFFER_PER_UID
:
2310 ret
= create_channel_per_uid(app
, usess
, ua_sess
, ua_chan
);
2316 case LTTNG_BUFFER_PER_PID
:
2318 ret
= create_channel_per_pid(app
, usess
, ua_sess
, ua_chan
);
2330 /* Initialize ust objd object using the received handle and add it. */
2331 lttng_ht_node_init_ulong(&ua_chan
->ust_objd_node
, ua_chan
->handle
);
2332 lttng_ht_add_unique_ulong(app
->ust_objd
, &ua_chan
->ust_objd_node
);
2334 /* If channel is not enabled, disable it on the tracer */
2335 if (!ua_chan
->enabled
) {
2336 ret
= disable_ust_channel(app
, ua_sess
, ua_chan
);
2347 * Create UST app channel and create it on the tracer. Set ua_chanp of the
2348 * newly created channel if not NULL.
2350 * Called with UST app session lock held.
2352 * Return 0 on success or else a negative value.
2354 static int create_ust_app_channel(struct ust_app_session
*ua_sess
,
2355 struct ltt_ust_channel
*uchan
, struct ust_app
*app
,
2356 enum lttng_ust_chan_type type
, struct ltt_ust_session
*usess
,
2357 struct ust_app_channel
**ua_chanp
)
2360 struct lttng_ht_iter iter
;
2361 struct lttng_ht_node_str
*ua_chan_node
;
2362 struct ust_app_channel
*ua_chan
;
2364 /* Lookup channel in the ust app session */
2365 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &iter
);
2366 ua_chan_node
= lttng_ht_iter_get_node_str(&iter
);
2367 if (ua_chan_node
!= NULL
) {
2368 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
2372 ua_chan
= alloc_ust_app_channel(uchan
->name
, ua_sess
, &uchan
->attr
);
2373 if (ua_chan
== NULL
) {
2374 /* Only malloc can fail here */
2378 shadow_copy_channel(ua_chan
, uchan
);
2380 /* Set channel type. */
2381 ua_chan
->attr
.type
= type
;
2383 ret
= do_create_channel(app
, usess
, ua_sess
, ua_chan
);
2388 DBG2("UST app create channel %s for PID %d completed", ua_chan
->name
,
2391 /* Only add the channel if successful on the tracer side. */
2392 lttng_ht_add_unique_str(ua_sess
->channels
, &ua_chan
->node
);
2396 *ua_chanp
= ua_chan
;
2399 /* Everything went well. */
2403 delete_ust_app_channel(ua_chan
->is_sent
? app
->sock
: -1, ua_chan
, app
);
2408 * Create UST app event and create it on the tracer side.
2410 * Called with ust app session mutex held.
2413 int create_ust_app_event(struct ust_app_session
*ua_sess
,
2414 struct ust_app_channel
*ua_chan
, struct ltt_ust_event
*uevent
,
2415 struct ust_app
*app
)
2418 struct ust_app_event
*ua_event
;
2420 /* Get event node */
2421 ua_event
= find_ust_app_event(ua_chan
->events
, uevent
->attr
.name
,
2422 uevent
->filter
, uevent
->attr
.loglevel
);
2423 if (ua_event
!= NULL
) {
2428 /* Does not exist so create one */
2429 ua_event
= alloc_ust_app_event(uevent
->attr
.name
, &uevent
->attr
);
2430 if (ua_event
== NULL
) {
2431 /* Only malloc can failed so something is really wrong */
2435 shadow_copy_event(ua_event
, uevent
);
2437 /* Create it on the tracer side */
2438 ret
= create_ust_event(app
, ua_sess
, ua_chan
, ua_event
);
2440 /* Not found previously means that it does not exist on the tracer */
2441 assert(ret
!= -LTTNG_UST_ERR_EXIST
);
2445 add_unique_ust_app_event(ua_chan
, ua_event
);
2447 DBG2("UST app create event %s for PID %d completed", ua_event
->name
,
2454 /* Valid. Calling here is already in a read side lock */
2455 delete_ust_app_event(-1, ua_event
);
2460 * Create UST metadata and open it on the tracer side.
2462 * Called with UST app session lock held and RCU read side lock.
2464 static int create_ust_app_metadata(struct ust_app_session
*ua_sess
,
2465 struct ust_app
*app
, struct consumer_output
*consumer
,
2466 struct ustctl_consumer_channel_attr
*attr
)
2469 struct ust_app_channel
*metadata
;
2470 struct consumer_socket
*socket
;
2471 struct ust_registry_session
*registry
;
2477 registry
= get_session_registry(ua_sess
);
2480 /* Metadata already exists for this registry. */
2481 if (registry
->metadata_key
) {
2486 /* Allocate UST metadata */
2487 metadata
= alloc_ust_app_channel(DEFAULT_METADATA_NAME
, ua_sess
, NULL
);
2489 /* malloc() failed */
2495 /* Set default attributes for metadata. */
2496 metadata
->attr
.overwrite
= DEFAULT_CHANNEL_OVERWRITE
;
2497 metadata
->attr
.subbuf_size
= default_get_metadata_subbuf_size();
2498 metadata
->attr
.num_subbuf
= DEFAULT_METADATA_SUBBUF_NUM
;
2499 metadata
->attr
.switch_timer_interval
= DEFAULT_UST_CHANNEL_SWITCH_TIMER
;
2500 metadata
->attr
.read_timer_interval
= DEFAULT_UST_CHANNEL_READ_TIMER
;
2501 metadata
->attr
.output
= LTTNG_UST_MMAP
;
2502 metadata
->attr
.type
= LTTNG_UST_CHAN_METADATA
;
2504 memcpy(&metadata
->attr
, attr
, sizeof(metadata
->attr
));
2505 metadata
->attr
.output
= LTTNG_UST_MMAP
;
2506 metadata
->attr
.type
= LTTNG_UST_CHAN_METADATA
;
2509 /* Get the right consumer socket for the application. */
2510 socket
= consumer_find_socket_by_bitness(app
->bits_per_long
, consumer
);
2513 goto error_consumer
;
2516 /* Need one fd for the channel. */
2517 ret
= lttng_fd_get(LTTNG_FD_APPS
, 1);
2519 ERR("Exhausted number of available FD upon create metadata");
2524 * Keep metadata key so we can identify it on the consumer side. Assign it
2525 * to the registry *before* we ask the consumer so we avoid the race of the
2526 * consumer requesting the metadata and the ask_channel call on our side
2527 * did not returned yet.
2529 registry
->metadata_key
= metadata
->key
;
2532 * Ask the metadata channel creation to the consumer. The metadata object
2533 * will be created by the consumer and kept their. However, the stream is
2534 * never added or monitored until we do a first push metadata to the
2537 ret
= ust_consumer_ask_channel(ua_sess
, metadata
, consumer
, socket
,
2541 * Safe because the metadata obj pointer is not set so the delete below
2542 * will not put a FD back again.
2544 lttng_fd_put(LTTNG_FD_APPS
, 1);
2545 goto error_consumer
;
2549 * The setup command will make the metadata stream be sent to the relayd,
2550 * if applicable, and the thread managing the metadatas. This is important
2551 * because after this point, if an error occurs, the only way the stream
2552 * can be deleted is to be monitored in the consumer.
2554 ret
= consumer_setup_metadata(socket
, metadata
->key
);
2557 * Safe because the metadata obj pointer is not set so the delete below
2558 * will not put a FD back again.
2560 lttng_fd_put(LTTNG_FD_APPS
, 1);
2561 goto error_consumer
;
2564 DBG2("UST metadata with key %" PRIu64
" created for app pid %d",
2565 metadata
->key
, app
->pid
);
2568 delete_ust_app_channel(-1, metadata
, app
);
2574 * Return pointer to traceable apps list.
2576 struct lttng_ht
*ust_app_get_ht(void)
2582 * Return ust app pointer or NULL if not found. RCU read side lock MUST be
2583 * acquired before calling this function.
2585 struct ust_app
*ust_app_find_by_pid(pid_t pid
)
2587 struct ust_app
*app
= NULL
;
2588 struct lttng_ht_node_ulong
*node
;
2589 struct lttng_ht_iter iter
;
2591 lttng_ht_lookup(ust_app_ht
, (void *)((unsigned long) pid
), &iter
);
2592 node
= lttng_ht_iter_get_node_ulong(&iter
);
2594 DBG2("UST app no found with pid %d", pid
);
2598 DBG2("Found UST app by pid %d", pid
);
2600 app
= caa_container_of(node
, struct ust_app
, pid_n
);
2607 * Allocate and init an UST app object using the registration information and
2608 * the command socket. This is called when the command socket connects to the
2611 * The object is returned on success or else NULL.
2613 struct ust_app
*ust_app_create(struct ust_register_msg
*msg
, int sock
)
2615 struct ust_app
*lta
= NULL
;
2620 DBG3("UST app creating application for socket %d", sock
);
2622 if ((msg
->bits_per_long
== 64 &&
2623 (uatomic_read(&ust_consumerd64_fd
) == -EINVAL
))
2624 || (msg
->bits_per_long
== 32 &&
2625 (uatomic_read(&ust_consumerd32_fd
) == -EINVAL
))) {
2626 ERR("Registration failed: application \"%s\" (pid: %d) has "
2627 "%d-bit long, but no consumerd for this size is available.\n",
2628 msg
->name
, msg
->pid
, msg
->bits_per_long
);
2632 lta
= zmalloc(sizeof(struct ust_app
));
2638 lta
->ppid
= msg
->ppid
;
2639 lta
->uid
= msg
->uid
;
2640 lta
->gid
= msg
->gid
;
2642 lta
->bits_per_long
= msg
->bits_per_long
;
2643 lta
->uint8_t_alignment
= msg
->uint8_t_alignment
;
2644 lta
->uint16_t_alignment
= msg
->uint16_t_alignment
;
2645 lta
->uint32_t_alignment
= msg
->uint32_t_alignment
;
2646 lta
->uint64_t_alignment
= msg
->uint64_t_alignment
;
2647 lta
->long_alignment
= msg
->long_alignment
;
2648 lta
->byte_order
= msg
->byte_order
;
2650 lta
->v_major
= msg
->major
;
2651 lta
->v_minor
= msg
->minor
;
2652 lta
->sessions
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
2653 lta
->ust_objd
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
2654 lta
->notify_sock
= -1;
2656 /* Copy name and make sure it's NULL terminated. */
2657 strncpy(lta
->name
, msg
->name
, sizeof(lta
->name
));
2658 lta
->name
[UST_APP_PROCNAME_LEN
] = '\0';
2661 * Before this can be called, when receiving the registration information,
2662 * the application compatibility is checked. So, at this point, the
2663 * application can work with this session daemon.
2665 lta
->compatible
= 1;
2667 lta
->pid
= msg
->pid
;
2668 lttng_ht_node_init_ulong(<a
->pid_n
, (unsigned long) lta
->pid
);
2670 lttng_ht_node_init_ulong(<a
->sock_n
, (unsigned long) lta
->sock
);
2672 CDS_INIT_LIST_HEAD(<a
->teardown_head
);
2679 * For a given application object, add it to every hash table.
2681 void ust_app_add(struct ust_app
*app
)
2684 assert(app
->notify_sock
>= 0);
2689 * On a re-registration, we want to kick out the previous registration of
2692 lttng_ht_add_replace_ulong(ust_app_ht
, &app
->pid_n
);
2695 * The socket _should_ be unique until _we_ call close. So, a add_unique
2696 * for the ust_app_ht_by_sock is used which asserts fail if the entry was
2697 * already in the table.
2699 lttng_ht_add_unique_ulong(ust_app_ht_by_sock
, &app
->sock_n
);
2701 /* Add application to the notify socket hash table. */
2702 lttng_ht_node_init_ulong(&app
->notify_sock_n
, app
->notify_sock
);
2703 lttng_ht_add_unique_ulong(ust_app_ht_by_notify_sock
, &app
->notify_sock_n
);
2705 DBG("App registered with pid:%d ppid:%d uid:%d gid:%d sock:%d name:%s "
2706 "notify_sock:%d (version %d.%d)", app
->pid
, app
->ppid
, app
->uid
,
2707 app
->gid
, app
->sock
, app
->name
, app
->notify_sock
, app
->v_major
,
2714 * Set the application version into the object.
2716 * Return 0 on success else a negative value either an errno code or a
2717 * LTTng-UST error code.
2719 int ust_app_version(struct ust_app
*app
)
2725 ret
= ustctl_tracer_version(app
->sock
, &app
->version
);
2727 if (ret
!= -LTTNG_UST_ERR_EXITING
&& ret
!= -EPIPE
) {
2728 ERR("UST app %d verson failed with ret %d", app
->sock
, ret
);
2730 DBG3("UST app %d verion failed. Application is dead", app
->sock
);
2738 * Unregister app by removing it from the global traceable app list and freeing
2741 * The socket is already closed at this point so no close to sock.
2743 void ust_app_unregister(int sock
)
2745 struct ust_app
*lta
;
2746 struct lttng_ht_node_ulong
*node
;
2747 struct lttng_ht_iter iter
;
2748 struct ust_app_session
*ua_sess
;
2753 /* Get the node reference for a call_rcu */
2754 lttng_ht_lookup(ust_app_ht_by_sock
, (void *)((unsigned long) sock
), &iter
);
2755 node
= lttng_ht_iter_get_node_ulong(&iter
);
2758 lta
= caa_container_of(node
, struct ust_app
, sock_n
);
2759 DBG("PID %d unregistering with sock %d", lta
->pid
, sock
);
2761 /* Remove application from PID hash table */
2762 ret
= lttng_ht_del(ust_app_ht_by_sock
, &iter
);
2766 * Remove application from notify hash table. The thread handling the
2767 * notify socket could have deleted the node so ignore on error because
2768 * either way it's valid. The close of that socket is handled by the other
2771 iter
.iter
.node
= <a
->notify_sock_n
.node
;
2772 (void) lttng_ht_del(ust_app_ht_by_notify_sock
, &iter
);
2775 * Ignore return value since the node might have been removed before by an
2776 * add replace during app registration because the PID can be reassigned by
2779 iter
.iter
.node
= <a
->pid_n
.node
;
2780 ret
= lttng_ht_del(ust_app_ht
, &iter
);
2782 DBG3("Unregister app by PID %d failed. This can happen on pid reuse",
2786 /* Remove sessions so they are not visible during deletion.*/
2787 cds_lfht_for_each_entry(lta
->sessions
->ht
, &iter
.iter
, ua_sess
,
2789 struct ust_registry_session
*registry
;
2791 ret
= lttng_ht_del(lta
->sessions
, &iter
);
2793 /* The session was already removed so scheduled for teardown. */
2798 * Add session to list for teardown. This is safe since at this point we
2799 * are the only one using this list.
2801 pthread_mutex_lock(&ua_sess
->lock
);
2804 * Normally, this is done in the delete session process which is
2805 * executed in the call rcu below. However, upon registration we can't
2806 * afford to wait for the grace period before pushing data or else the
2807 * data pending feature can race between the unregistration and stop
2808 * command where the data pending command is sent *before* the grace
2811 * The close metadata below nullifies the metadata pointer in the
2812 * session so the delete session will NOT push/close a second time.
2814 registry
= get_session_registry(ua_sess
);
2816 /* Push metadata for application before freeing the application. */
2817 (void) push_metadata(registry
, ua_sess
->consumer
);
2820 * Don't ask to close metadata for global per UID buffers. Close
2821 * metadata only on destroy trace session in this case.
2823 if (ua_sess
->buffer_type
!= LTTNG_BUFFER_PER_UID
) {
2824 /* And ask to close it for this session registry. */
2825 (void) close_metadata(registry
, ua_sess
->consumer
);
2829 cds_list_add(&ua_sess
->teardown_node
, <a
->teardown_head
);
2830 pthread_mutex_unlock(&ua_sess
->lock
);
2834 call_rcu(<a
->pid_n
.head
, delete_ust_app_rcu
);
2841 * Return traceable_app_count
2843 unsigned long ust_app_list_count(void)
2845 unsigned long count
;
2848 count
= lttng_ht_get_count(ust_app_ht
);
2855 * Fill events array with all events name of all registered apps.
2857 int ust_app_list_events(struct lttng_event
**events
)
2860 size_t nbmem
, count
= 0;
2861 struct lttng_ht_iter iter
;
2862 struct ust_app
*app
;
2863 struct lttng_event
*tmp_event
;
2865 nbmem
= UST_APP_EVENT_LIST_SIZE
;
2866 tmp_event
= zmalloc(nbmem
* sizeof(struct lttng_event
));
2867 if (tmp_event
== NULL
) {
2868 PERROR("zmalloc ust app events");
2875 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
2876 struct lttng_ust_tracepoint_iter uiter
;
2878 health_code_update();
2880 if (!app
->compatible
) {
2882 * TODO: In time, we should notice the caller of this error by
2883 * telling him that this is a version error.
2887 handle
= ustctl_tracepoint_list(app
->sock
);
2889 if (handle
!= -EPIPE
&& handle
!= -LTTNG_UST_ERR_EXITING
) {
2890 ERR("UST app list events getting handle failed for app pid %d",
2896 while ((ret
= ustctl_tracepoint_list_get(app
->sock
, handle
,
2897 &uiter
)) != -LTTNG_UST_ERR_NOENT
) {
2898 /* Handle ustctl error. */
2901 if (ret
!= -LTTNG_UST_ERR_EXITING
|| ret
!= -EPIPE
) {
2902 ERR("UST app tp list get failed for app %d with ret %d",
2905 DBG3("UST app tp list get failed. Application is dead");
2910 health_code_update();
2911 if (count
>= nbmem
) {
2912 /* In case the realloc fails, we free the memory */
2915 DBG2("Reallocating event list from %zu to %zu entries", nbmem
,
2918 ptr
= realloc(tmp_event
, nbmem
* sizeof(struct lttng_event
));
2920 PERROR("realloc ust app events");
2927 memcpy(tmp_event
[count
].name
, uiter
.name
, LTTNG_UST_SYM_NAME_LEN
);
2928 tmp_event
[count
].loglevel
= uiter
.loglevel
;
2929 tmp_event
[count
].type
= (enum lttng_event_type
) LTTNG_UST_TRACEPOINT
;
2930 tmp_event
[count
].pid
= app
->pid
;
2931 tmp_event
[count
].enabled
= -1;
2937 *events
= tmp_event
;
2939 DBG2("UST app list events done (%zu events)", count
);
2944 health_code_update();
2949 * Fill events array with all events name of all registered apps.
2951 int ust_app_list_event_fields(struct lttng_event_field
**fields
)
2954 size_t nbmem
, count
= 0;
2955 struct lttng_ht_iter iter
;
2956 struct ust_app
*app
;
2957 struct lttng_event_field
*tmp_event
;
2959 nbmem
= UST_APP_EVENT_LIST_SIZE
;
2960 tmp_event
= zmalloc(nbmem
* sizeof(struct lttng_event_field
));
2961 if (tmp_event
== NULL
) {
2962 PERROR("zmalloc ust app event fields");
2969 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
2970 struct lttng_ust_field_iter uiter
;
2972 health_code_update();
2974 if (!app
->compatible
) {
2976 * TODO: In time, we should notice the caller of this error by
2977 * telling him that this is a version error.
2981 handle
= ustctl_tracepoint_field_list(app
->sock
);
2983 if (handle
!= -EPIPE
&& handle
!= -LTTNG_UST_ERR_EXITING
) {
2984 ERR("UST app list field getting handle failed for app pid %d",
2990 while ((ret
= ustctl_tracepoint_field_list_get(app
->sock
, handle
,
2991 &uiter
)) != -LTTNG_UST_ERR_NOENT
) {
2992 /* Handle ustctl error. */
2995 if (ret
!= -LTTNG_UST_ERR_EXITING
|| ret
!= -EPIPE
) {
2996 ERR("UST app tp list field failed for app %d with ret %d",
2999 DBG3("UST app tp list field failed. Application is dead");
3004 health_code_update();
3005 if (count
>= nbmem
) {
3006 /* In case the realloc fails, we free the memory */
3009 DBG2("Reallocating event field list from %zu to %zu entries", nbmem
,
3012 ptr
= realloc(tmp_event
, nbmem
* sizeof(struct lttng_event_field
));
3014 PERROR("realloc ust app event fields");
3022 memcpy(tmp_event
[count
].field_name
, uiter
.field_name
, LTTNG_UST_SYM_NAME_LEN
);
3023 tmp_event
[count
].type
= uiter
.type
;
3024 tmp_event
[count
].nowrite
= uiter
.nowrite
;
3026 memcpy(tmp_event
[count
].event
.name
, uiter
.event_name
, LTTNG_UST_SYM_NAME_LEN
);
3027 tmp_event
[count
].event
.loglevel
= uiter
.loglevel
;
3028 tmp_event
[count
].event
.type
= LTTNG_UST_TRACEPOINT
;
3029 tmp_event
[count
].event
.pid
= app
->pid
;
3030 tmp_event
[count
].event
.enabled
= -1;
3036 *fields
= tmp_event
;
3038 DBG2("UST app list event fields done (%zu events)", count
);
3043 health_code_update();
3048 * Free and clean all traceable apps of the global list.
3050 void ust_app_clean_list(void)
3053 struct ust_app
*app
;
3054 struct lttng_ht_iter iter
;
3056 DBG2("UST app cleaning registered apps hash table");
3060 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3061 ret
= lttng_ht_del(ust_app_ht
, &iter
);
3063 call_rcu(&app
->pid_n
.head
, delete_ust_app_rcu
);
3066 /* Cleanup socket hash table */
3067 cds_lfht_for_each_entry(ust_app_ht_by_sock
->ht
, &iter
.iter
, app
,
3069 ret
= lttng_ht_del(ust_app_ht_by_sock
, &iter
);
3073 /* Cleanup notify socket hash table */
3074 cds_lfht_for_each_entry(ust_app_ht_by_notify_sock
->ht
, &iter
.iter
, app
,
3075 notify_sock_n
.node
) {
3076 ret
= lttng_ht_del(ust_app_ht_by_notify_sock
, &iter
);
3080 /* Destroy is done only when the ht is empty */
3081 lttng_ht_destroy(ust_app_ht
);
3082 lttng_ht_destroy(ust_app_ht_by_sock
);
3083 lttng_ht_destroy(ust_app_ht_by_notify_sock
);
3089 * Init UST app hash table.
3091 void ust_app_ht_alloc(void)
3093 ust_app_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
3094 ust_app_ht_by_sock
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
3095 ust_app_ht_by_notify_sock
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
3099 * For a specific UST session, disable the channel for all registered apps.
3101 int ust_app_disable_channel_glb(struct ltt_ust_session
*usess
,
3102 struct ltt_ust_channel
*uchan
)
3105 struct lttng_ht_iter iter
;
3106 struct lttng_ht_node_str
*ua_chan_node
;
3107 struct ust_app
*app
;
3108 struct ust_app_session
*ua_sess
;
3109 struct ust_app_channel
*ua_chan
;
3111 if (usess
== NULL
|| uchan
== NULL
) {
3112 ERR("Disabling UST global channel with NULL values");
3117 DBG2("UST app disabling channel %s from global domain for session id %d",
3118 uchan
->name
, usess
->id
);
3122 /* For every registered applications */
3123 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3124 struct lttng_ht_iter uiter
;
3125 if (!app
->compatible
) {
3127 * TODO: In time, we should notice the caller of this error by
3128 * telling him that this is a version error.
3132 ua_sess
= lookup_session_by_app(usess
, app
);
3133 if (ua_sess
== NULL
) {
3138 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
3139 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
3140 /* If the session if found for the app, the channel must be there */
3141 assert(ua_chan_node
);
3143 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
3144 /* The channel must not be already disabled */
3145 assert(ua_chan
->enabled
== 1);
3147 /* Disable channel onto application */
3148 ret
= disable_ust_app_channel(ua_sess
, ua_chan
, app
);
3150 /* XXX: We might want to report this error at some point... */
3162 * For a specific UST session, enable the channel for all registered apps.
3164 int ust_app_enable_channel_glb(struct ltt_ust_session
*usess
,
3165 struct ltt_ust_channel
*uchan
)
3168 struct lttng_ht_iter iter
;
3169 struct ust_app
*app
;
3170 struct ust_app_session
*ua_sess
;
3172 if (usess
== NULL
|| uchan
== NULL
) {
3173 ERR("Adding UST global channel to NULL values");
3178 DBG2("UST app enabling channel %s to global domain for session id %d",
3179 uchan
->name
, usess
->id
);
3183 /* For every registered applications */
3184 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3185 if (!app
->compatible
) {
3187 * TODO: In time, we should notice the caller of this error by
3188 * telling him that this is a version error.
3192 ua_sess
= lookup_session_by_app(usess
, app
);
3193 if (ua_sess
== NULL
) {
3197 /* Enable channel onto application */
3198 ret
= enable_ust_app_channel(ua_sess
, uchan
, app
);
3200 /* XXX: We might want to report this error at some point... */
3212 * Disable an event in a channel and for a specific session.
3214 int ust_app_disable_event_glb(struct ltt_ust_session
*usess
,
3215 struct ltt_ust_channel
*uchan
, struct ltt_ust_event
*uevent
)
3218 struct lttng_ht_iter iter
, uiter
;
3219 struct lttng_ht_node_str
*ua_chan_node
, *ua_event_node
;
3220 struct ust_app
*app
;
3221 struct ust_app_session
*ua_sess
;
3222 struct ust_app_channel
*ua_chan
;
3223 struct ust_app_event
*ua_event
;
3225 DBG("UST app disabling event %s for all apps in channel "
3226 "%s for session id %d", uevent
->attr
.name
, uchan
->name
, usess
->id
);
3230 /* For all registered applications */
3231 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3232 if (!app
->compatible
) {
3234 * TODO: In time, we should notice the caller of this error by
3235 * telling him that this is a version error.
3239 ua_sess
= lookup_session_by_app(usess
, app
);
3240 if (ua_sess
== NULL
) {
3245 /* Lookup channel in the ust app session */
3246 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
3247 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
3248 if (ua_chan_node
== NULL
) {
3249 DBG2("Channel %s not found in session id %d for app pid %d."
3250 "Skipping", uchan
->name
, usess
->id
, app
->pid
);
3253 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
3255 lttng_ht_lookup(ua_chan
->events
, (void *)uevent
->attr
.name
, &uiter
);
3256 ua_event_node
= lttng_ht_iter_get_node_str(&uiter
);
3257 if (ua_event_node
== NULL
) {
3258 DBG2("Event %s not found in channel %s for app pid %d."
3259 "Skipping", uevent
->attr
.name
, uchan
->name
, app
->pid
);
3262 ua_event
= caa_container_of(ua_event_node
, struct ust_app_event
, node
);
3264 ret
= disable_ust_app_event(ua_sess
, ua_event
, app
);
3266 /* XXX: Report error someday... */
3277 * For a specific UST session and UST channel, the event for all
3280 int ust_app_disable_all_event_glb(struct ltt_ust_session
*usess
,
3281 struct ltt_ust_channel
*uchan
)
3284 struct lttng_ht_iter iter
, uiter
;
3285 struct lttng_ht_node_str
*ua_chan_node
;
3286 struct ust_app
*app
;
3287 struct ust_app_session
*ua_sess
;
3288 struct ust_app_channel
*ua_chan
;
3289 struct ust_app_event
*ua_event
;
3291 DBG("UST app disabling all event for all apps in channel "
3292 "%s for session id %d", uchan
->name
, usess
->id
);
3296 /* For all registered applications */
3297 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3298 if (!app
->compatible
) {
3300 * TODO: In time, we should notice the caller of this error by
3301 * telling him that this is a version error.
3305 ua_sess
= lookup_session_by_app(usess
, app
);
3307 /* The application has problem or is probably dead. */
3311 /* Lookup channel in the ust app session */
3312 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
3313 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
3314 /* If the channel is not found, there is a code flow error */
3315 assert(ua_chan_node
);
3317 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
3319 /* Disable each events of channel */
3320 cds_lfht_for_each_entry(ua_chan
->events
->ht
, &uiter
.iter
, ua_event
,
3322 ret
= disable_ust_app_event(ua_sess
, ua_event
, app
);
3324 /* XXX: Report error someday... */
3336 * For a specific UST session, create the channel for all registered apps.
3338 int ust_app_create_channel_glb(struct ltt_ust_session
*usess
,
3339 struct ltt_ust_channel
*uchan
)
3341 int ret
= 0, created
;
3342 struct lttng_ht_iter iter
;
3343 struct ust_app
*app
;
3344 struct ust_app_session
*ua_sess
= NULL
;
3346 /* Very wrong code flow */
3350 DBG2("UST app adding channel %s to UST domain for session id %d",
3351 uchan
->name
, usess
->id
);
3355 /* For every registered applications */
3356 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3357 if (!app
->compatible
) {
3359 * TODO: In time, we should notice the caller of this error by
3360 * telling him that this is a version error.
3365 * Create session on the tracer side and add it to app session HT. Note
3366 * that if session exist, it will simply return a pointer to the ust
3369 ret
= create_ust_app_session(usess
, app
, &ua_sess
, &created
);
3374 * The application's socket is not valid. Either a bad socket
3375 * or a timeout on it. We can't inform the caller that for a
3376 * specific app, the session failed so lets continue here.
3381 goto error_rcu_unlock
;
3386 pthread_mutex_lock(&ua_sess
->lock
);
3387 if (!strncmp(uchan
->name
, DEFAULT_METADATA_NAME
,
3388 sizeof(uchan
->name
))) {
3389 struct ustctl_consumer_channel_attr attr
;
3390 copy_channel_attr_to_ustctl(&attr
, &uchan
->attr
);
3391 ret
= create_ust_app_metadata(ua_sess
, app
, usess
->consumer
,
3394 /* Create channel onto application. We don't need the chan ref. */
3395 ret
= create_ust_app_channel(ua_sess
, uchan
, app
,
3396 LTTNG_UST_CHAN_PER_CPU
, usess
, NULL
);
3398 pthread_mutex_unlock(&ua_sess
->lock
);
3400 if (ret
== -ENOMEM
) {
3401 /* No more memory is a fatal error. Stop right now. */
3402 goto error_rcu_unlock
;
3404 /* Cleanup the created session if it's the case. */
3406 destroy_app_session(app
, ua_sess
);
3417 * Enable event for a specific session and channel on the tracer.
3419 int ust_app_enable_event_glb(struct ltt_ust_session
*usess
,
3420 struct ltt_ust_channel
*uchan
, struct ltt_ust_event
*uevent
)
3423 struct lttng_ht_iter iter
, uiter
;
3424 struct lttng_ht_node_str
*ua_chan_node
;
3425 struct ust_app
*app
;
3426 struct ust_app_session
*ua_sess
;
3427 struct ust_app_channel
*ua_chan
;
3428 struct ust_app_event
*ua_event
;
3430 DBG("UST app enabling event %s for all apps for session id %d",
3431 uevent
->attr
.name
, usess
->id
);
3434 * NOTE: At this point, this function is called only if the session and
3435 * channel passed are already created for all apps. and enabled on the
3441 /* For all registered applications */
3442 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3443 if (!app
->compatible
) {
3445 * TODO: In time, we should notice the caller of this error by
3446 * telling him that this is a version error.
3450 ua_sess
= lookup_session_by_app(usess
, app
);
3452 /* The application has problem or is probably dead. */
3456 pthread_mutex_lock(&ua_sess
->lock
);
3458 /* Lookup channel in the ust app session */
3459 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
3460 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
3461 /* If the channel is not found, there is a code flow error */
3462 assert(ua_chan_node
);
3464 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
3466 /* Get event node */
3467 ua_event
= find_ust_app_event(ua_chan
->events
, uevent
->attr
.name
,
3468 uevent
->filter
, uevent
->attr
.loglevel
);
3469 if (ua_event
== NULL
) {
3470 DBG3("UST app enable event %s not found for app PID %d."
3471 "Skipping app", uevent
->attr
.name
, app
->pid
);
3475 ret
= enable_ust_app_event(ua_sess
, ua_event
, app
);
3477 pthread_mutex_unlock(&ua_sess
->lock
);
3481 pthread_mutex_unlock(&ua_sess
->lock
);
3490 * For a specific existing UST session and UST channel, creates the event for
3491 * all registered apps.
3493 int ust_app_create_event_glb(struct ltt_ust_session
*usess
,
3494 struct ltt_ust_channel
*uchan
, struct ltt_ust_event
*uevent
)
3497 struct lttng_ht_iter iter
, uiter
;
3498 struct lttng_ht_node_str
*ua_chan_node
;
3499 struct ust_app
*app
;
3500 struct ust_app_session
*ua_sess
;
3501 struct ust_app_channel
*ua_chan
;
3503 DBG("UST app creating event %s for all apps for session id %d",
3504 uevent
->attr
.name
, usess
->id
);
3508 /* For all registered applications */
3509 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3510 if (!app
->compatible
) {
3512 * TODO: In time, we should notice the caller of this error by
3513 * telling him that this is a version error.
3517 ua_sess
= lookup_session_by_app(usess
, app
);
3519 /* The application has problem or is probably dead. */
3523 pthread_mutex_lock(&ua_sess
->lock
);
3524 /* Lookup channel in the ust app session */
3525 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
3526 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
3527 /* If the channel is not found, there is a code flow error */
3528 assert(ua_chan_node
);
3530 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
3532 ret
= create_ust_app_event(ua_sess
, ua_chan
, uevent
, app
);
3533 pthread_mutex_unlock(&ua_sess
->lock
);
3535 if (ret
!= -LTTNG_UST_ERR_EXIST
) {
3536 /* Possible value at this point: -ENOMEM. If so, we stop! */
3539 DBG2("UST app event %s already exist on app PID %d",
3540 uevent
->attr
.name
, app
->pid
);
3551 * Start tracing for a specific UST session and app.
3553 int ust_app_start_trace(struct ltt_ust_session
*usess
, struct ust_app
*app
)
3556 struct ust_app_session
*ua_sess
;
3558 DBG("Starting tracing for ust app pid %d", app
->pid
);
3562 if (!app
->compatible
) {
3566 ua_sess
= lookup_session_by_app(usess
, app
);
3567 if (ua_sess
== NULL
) {
3568 /* The session is in teardown process. Ignore and continue. */
3572 pthread_mutex_lock(&ua_sess
->lock
);
3574 /* Upon restart, we skip the setup, already done */
3575 if (ua_sess
->started
) {
3579 /* Create directories if consumer is LOCAL and has a path defined. */
3580 if (usess
->consumer
->type
== CONSUMER_DST_LOCAL
&&
3581 strlen(usess
->consumer
->dst
.trace_path
) > 0) {
3582 ret
= run_as_mkdir_recursive(usess
->consumer
->dst
.trace_path
,
3583 S_IRWXU
| S_IRWXG
, ua_sess
->euid
, ua_sess
->egid
);
3585 if (ret
!= -EEXIST
) {
3586 ERR("Trace directory creation error");
3593 * Create the metadata for the application. This returns gracefully if a
3594 * metadata was already set for the session.
3596 ret
= create_ust_app_metadata(ua_sess
, app
, usess
->consumer
, NULL
);
3601 health_code_update();
3604 /* This start the UST tracing */
3605 ret
= ustctl_start_session(app
->sock
, ua_sess
->handle
);
3607 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3608 ERR("Error starting tracing for app pid: %d (ret: %d)",
3611 DBG("UST app start session failed. Application is dead.");
3616 /* Indicate that the session has been started once */
3617 ua_sess
->started
= 1;
3619 pthread_mutex_unlock(&ua_sess
->lock
);
3621 health_code_update();
3623 /* Quiescent wait after starting trace */
3624 ret
= ustctl_wait_quiescent(app
->sock
);
3625 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3626 ERR("UST app wait quiescent failed for app pid %d ret %d",
3632 health_code_update();
3636 pthread_mutex_unlock(&ua_sess
->lock
);
3638 health_code_update();
3643 * Stop tracing for a specific UST session and app.
3645 int ust_app_stop_trace(struct ltt_ust_session
*usess
, struct ust_app
*app
)
3648 struct lttng_ht_iter iter
;
3649 struct ust_app_session
*ua_sess
;
3650 struct ust_app_channel
*ua_chan
;
3651 struct ust_registry_session
*registry
;
3653 DBG("Stopping tracing for ust app pid %d", app
->pid
);
3657 if (!app
->compatible
) {
3658 goto end_no_session
;
3661 ua_sess
= lookup_session_by_app(usess
, app
);
3662 if (ua_sess
== NULL
) {
3663 goto end_no_session
;
3666 pthread_mutex_lock(&ua_sess
->lock
);
3669 * If started = 0, it means that stop trace has been called for a session
3670 * that was never started. It's possible since we can have a fail start
3671 * from either the application manager thread or the command thread. Simply
3672 * indicate that this is a stop error.
3674 if (!ua_sess
->started
) {
3675 goto error_rcu_unlock
;
3678 health_code_update();
3680 /* This inhibits UST tracing */
3681 ret
= ustctl_stop_session(app
->sock
, ua_sess
->handle
);
3683 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3684 ERR("Error stopping tracing for app pid: %d (ret: %d)",
3687 DBG("UST app stop session failed. Application is dead.");
3689 goto error_rcu_unlock
;
3692 health_code_update();
3694 /* Quiescent wait after stopping trace */
3695 ret
= ustctl_wait_quiescent(app
->sock
);
3696 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3697 ERR("UST app wait quiescent failed for app pid %d ret %d",
3701 health_code_update();
3703 /* Flushing buffers */
3704 cds_lfht_for_each_entry(ua_sess
->channels
->ht
, &iter
.iter
, ua_chan
,
3706 health_code_update();
3707 assert(ua_chan
->is_sent
);
3708 ret
= ustctl_sock_flush_buffer(app
->sock
, ua_chan
->obj
);
3710 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3711 ERR("UST app PID %d channel %s flush failed with ret %d",
3712 app
->pid
, ua_chan
->name
, ret
);
3714 DBG3("UST app failed to flush %s. Application is dead.",
3716 /* No need to continue. */
3719 /* Continuing flushing all buffers */
3724 health_code_update();
3726 registry
= get_session_registry(ua_sess
);
3728 /* Push metadata for application before freeing the application. */
3729 (void) push_metadata(registry
, ua_sess
->consumer
);
3731 pthread_mutex_unlock(&ua_sess
->lock
);
3734 health_code_update();
3738 pthread_mutex_unlock(&ua_sess
->lock
);
3740 health_code_update();
3745 * Destroy a specific UST session in apps.
3747 static int destroy_trace(struct ltt_ust_session
*usess
, struct ust_app
*app
)
3750 struct ust_app_session
*ua_sess
;
3751 struct lttng_ht_iter iter
;
3752 struct lttng_ht_node_ulong
*node
;
3754 DBG("Destroy tracing for ust app pid %d", app
->pid
);
3758 if (!app
->compatible
) {
3762 __lookup_session_by_app(usess
, app
, &iter
);
3763 node
= lttng_ht_iter_get_node_ulong(&iter
);
3765 /* Session is being or is deleted. */
3768 ua_sess
= caa_container_of(node
, struct ust_app_session
, node
);
3770 health_code_update();
3771 destroy_app_session(app
, ua_sess
);
3773 health_code_update();
3775 /* Quiescent wait after stopping trace */
3776 ret
= ustctl_wait_quiescent(app
->sock
);
3777 if (ret
< 0 && ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
3778 ERR("UST app wait quiescent failed for app pid %d ret %d",
3783 health_code_update();
3788 * Start tracing for the UST session.
3790 int ust_app_start_trace_all(struct ltt_ust_session
*usess
)
3793 struct lttng_ht_iter iter
;
3794 struct ust_app
*app
;
3796 DBG("Starting all UST traces");
3800 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3801 ret
= ust_app_start_trace(usess
, app
);
3803 /* Continue to next apps even on error */
3814 * Start tracing for the UST session.
3816 int ust_app_stop_trace_all(struct ltt_ust_session
*usess
)
3819 struct lttng_ht_iter iter
;
3820 struct ust_app
*app
;
3822 DBG("Stopping all UST traces");
3826 /* Flush all per UID buffers associated to that session. */
3827 if (usess
->buffer_type
== LTTNG_BUFFER_PER_UID
) {
3828 struct buffer_reg_uid
*reg
;
3829 cds_list_for_each_entry(reg
, &usess
->buffer_reg_uid_list
, lnode
) {
3830 struct buffer_reg_channel
*reg_chan
;
3831 struct consumer_socket
*socket
;
3833 /* Get consumer socket to use to push the metadata.*/
3834 socket
= consumer_find_socket_by_bitness(reg
->bits_per_long
,
3837 /* Ignore request if no consumer is found for the session. */
3841 cds_lfht_for_each_entry(reg
->registry
->channels
->ht
, &iter
.iter
,
3842 reg_chan
, node
.node
) {
3844 * The following call will print error values so the return
3845 * code is of little importance because whatever happens, we
3846 * have to try them all.
3848 (void) consumer_flush_channel(socket
, reg_chan
->consumer_key
);
3853 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3854 ret
= ust_app_stop_trace(usess
, app
);
3856 /* Continue to next apps even on error */
3867 * Destroy app UST session.
3869 int ust_app_destroy_trace_all(struct ltt_ust_session
*usess
)
3872 struct lttng_ht_iter iter
;
3873 struct ust_app
*app
;
3875 DBG("Destroy all UST traces");
3879 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
3880 ret
= destroy_trace(usess
, app
);
3882 /* Continue to next apps even on error */
3893 * Add channels/events from UST global domain to registered apps at sock.
3895 void ust_app_global_update(struct ltt_ust_session
*usess
, int sock
)
3898 struct lttng_ht_iter iter
, uiter
, iter_ctx
;
3899 struct ust_app
*app
;
3900 struct ust_app_session
*ua_sess
= NULL
;
3901 struct ust_app_channel
*ua_chan
;
3902 struct ust_app_event
*ua_event
;
3903 struct ust_app_ctx
*ua_ctx
;
3908 DBG2("UST app global update for app sock %d for session id %d", sock
,
3913 app
= find_app_by_sock(sock
);
3916 * Application can be unregistered before so this is possible hence
3917 * simply stopping the update.
3919 DBG3("UST app update failed to find app sock %d", sock
);
3923 if (!app
->compatible
) {
3927 ret
= create_ust_app_session(usess
, app
, &ua_sess
, NULL
);
3929 /* Tracer is probably gone or ENOMEM. */
3934 pthread_mutex_lock(&ua_sess
->lock
);
3937 * We can iterate safely here over all UST app session since the create ust
3938 * app session above made a shadow copy of the UST global domain from the
3941 cds_lfht_for_each_entry(ua_sess
->channels
->ht
, &iter
.iter
, ua_chan
,
3944 * For a metadata channel, handle it differently.
3946 if (!strncmp(ua_chan
->name
, DEFAULT_METADATA_NAME
,
3947 sizeof(ua_chan
->name
))) {
3948 ret
= create_ust_app_metadata(ua_sess
, app
, usess
->consumer
,
3953 /* Remove it from the hash table and continue!. */
3954 ret
= lttng_ht_del(ua_sess
->channels
, &iter
);
3956 delete_ust_app_channel(-1, ua_chan
, app
);
3959 ret
= do_create_channel(app
, usess
, ua_sess
, ua_chan
);
3962 * Stop everything. On error, the application failed, no more
3963 * file descriptor are available or ENOMEM so stopping here is
3964 * the only thing we can do for now.
3970 cds_lfht_for_each_entry(ua_chan
->ctx
->ht
, &iter_ctx
.iter
, ua_ctx
,
3972 ret
= create_ust_channel_context(ua_chan
, ua_ctx
, app
);
3979 /* For each events */
3980 cds_lfht_for_each_entry(ua_chan
->events
->ht
, &uiter
.iter
, ua_event
,
3982 ret
= create_ust_event(app
, ua_sess
, ua_chan
, ua_event
);
3989 pthread_mutex_unlock(&ua_sess
->lock
);
3991 if (usess
->start_trace
) {
3992 ret
= ust_app_start_trace(usess
, app
);
3997 DBG2("UST trace started for app pid %d", app
->pid
);
4000 /* Everything went well at this point. */
4005 pthread_mutex_unlock(&ua_sess
->lock
);
4008 destroy_app_session(app
, ua_sess
);
4015 * Add context to a specific channel for global UST domain.
4017 int ust_app_add_ctx_channel_glb(struct ltt_ust_session
*usess
,
4018 struct ltt_ust_channel
*uchan
, struct ltt_ust_context
*uctx
)
4021 struct lttng_ht_node_str
*ua_chan_node
;
4022 struct lttng_ht_iter iter
, uiter
;
4023 struct ust_app_channel
*ua_chan
= NULL
;
4024 struct ust_app_session
*ua_sess
;
4025 struct ust_app
*app
;
4029 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
4030 if (!app
->compatible
) {
4032 * TODO: In time, we should notice the caller of this error by
4033 * telling him that this is a version error.
4037 ua_sess
= lookup_session_by_app(usess
, app
);
4038 if (ua_sess
== NULL
) {
4042 pthread_mutex_lock(&ua_sess
->lock
);
4043 /* Lookup channel in the ust app session */
4044 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &uiter
);
4045 ua_chan_node
= lttng_ht_iter_get_node_str(&uiter
);
4046 if (ua_chan_node
== NULL
) {
4049 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
,
4051 ret
= create_ust_app_channel_context(ua_sess
, ua_chan
, &uctx
->ctx
, app
);
4056 pthread_mutex_unlock(&ua_sess
->lock
);
4064 * Enable event for a channel from a UST session for a specific PID.
4066 int ust_app_enable_event_pid(struct ltt_ust_session
*usess
,
4067 struct ltt_ust_channel
*uchan
, struct ltt_ust_event
*uevent
, pid_t pid
)
4070 struct lttng_ht_iter iter
;
4071 struct lttng_ht_node_str
*ua_chan_node
;
4072 struct ust_app
*app
;
4073 struct ust_app_session
*ua_sess
;
4074 struct ust_app_channel
*ua_chan
;
4075 struct ust_app_event
*ua_event
;
4077 DBG("UST app enabling event %s for PID %d", uevent
->attr
.name
, pid
);
4081 app
= ust_app_find_by_pid(pid
);
4083 ERR("UST app enable event per PID %d not found", pid
);
4088 if (!app
->compatible
) {
4093 ua_sess
= lookup_session_by_app(usess
, app
);
4095 /* The application has problem or is probably dead. */
4100 pthread_mutex_lock(&ua_sess
->lock
);
4101 /* Lookup channel in the ust app session */
4102 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &iter
);
4103 ua_chan_node
= lttng_ht_iter_get_node_str(&iter
);
4104 /* If the channel is not found, there is a code flow error */
4105 assert(ua_chan_node
);
4107 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
4109 ua_event
= find_ust_app_event(ua_chan
->events
, uevent
->attr
.name
,
4110 uevent
->filter
, uevent
->attr
.loglevel
);
4111 if (ua_event
== NULL
) {
4112 ret
= create_ust_app_event(ua_sess
, ua_chan
, uevent
, app
);
4117 ret
= enable_ust_app_event(ua_sess
, ua_event
, app
);
4124 pthread_mutex_unlock(&ua_sess
->lock
);
4131 * Disable event for a channel from a UST session for a specific PID.
4133 int ust_app_disable_event_pid(struct ltt_ust_session
*usess
,
4134 struct ltt_ust_channel
*uchan
, struct ltt_ust_event
*uevent
, pid_t pid
)
4137 struct lttng_ht_iter iter
;
4138 struct lttng_ht_node_str
*ua_chan_node
, *ua_event_node
;
4139 struct ust_app
*app
;
4140 struct ust_app_session
*ua_sess
;
4141 struct ust_app_channel
*ua_chan
;
4142 struct ust_app_event
*ua_event
;
4144 DBG("UST app disabling event %s for PID %d", uevent
->attr
.name
, pid
);
4148 app
= ust_app_find_by_pid(pid
);
4150 ERR("UST app disable event per PID %d not found", pid
);
4155 if (!app
->compatible
) {
4160 ua_sess
= lookup_session_by_app(usess
, app
);
4162 /* The application has problem or is probably dead. */
4166 /* Lookup channel in the ust app session */
4167 lttng_ht_lookup(ua_sess
->channels
, (void *)uchan
->name
, &iter
);
4168 ua_chan_node
= lttng_ht_iter_get_node_str(&iter
);
4169 if (ua_chan_node
== NULL
) {
4170 /* Channel does not exist, skip disabling */
4173 ua_chan
= caa_container_of(ua_chan_node
, struct ust_app_channel
, node
);
4175 lttng_ht_lookup(ua_chan
->events
, (void *)uevent
->attr
.name
, &iter
);
4176 ua_event_node
= lttng_ht_iter_get_node_str(&iter
);
4177 if (ua_event_node
== NULL
) {
4178 /* Event does not exist, skip disabling */
4181 ua_event
= caa_container_of(ua_event_node
, struct ust_app_event
, node
);
4183 ret
= disable_ust_app_event(ua_sess
, ua_event
, app
);
4194 * Calibrate registered applications.
4196 int ust_app_calibrate_glb(struct lttng_ust_calibrate
*calibrate
)
4199 struct lttng_ht_iter iter
;
4200 struct ust_app
*app
;
4204 cds_lfht_for_each_entry(ust_app_ht
->ht
, &iter
.iter
, app
, pid_n
.node
) {
4205 if (!app
->compatible
) {
4207 * TODO: In time, we should notice the caller of this error by
4208 * telling him that this is a version error.
4213 health_code_update();
4215 ret
= ustctl_calibrate(app
->sock
, calibrate
);
4219 /* Means that it's not implemented on the tracer side. */
4223 DBG2("Calibrate app PID %d returned with error %d",
4230 DBG("UST app global domain calibration finished");
4234 health_code_update();
4240 * Receive registration and populate the given msg structure.
4242 * On success return 0 else a negative value returned by the ustctl call.
4244 int ust_app_recv_registration(int sock
, struct ust_register_msg
*msg
)
4247 uint32_t pid
, ppid
, uid
, gid
;
4251 ret
= ustctl_recv_reg_msg(sock
, &msg
->type
, &msg
->major
, &msg
->minor
,
4252 &pid
, &ppid
, &uid
, &gid
,
4253 &msg
->bits_per_long
,
4254 &msg
->uint8_t_alignment
,
4255 &msg
->uint16_t_alignment
,
4256 &msg
->uint32_t_alignment
,
4257 &msg
->uint64_t_alignment
,
4258 &msg
->long_alignment
,
4265 case LTTNG_UST_ERR_EXITING
:
4266 DBG3("UST app recv reg message failed. Application died");
4268 case LTTNG_UST_ERR_UNSUP_MAJOR
:
4269 ERR("UST app recv reg unsupported version %d.%d. Supporting %d.%d",
4270 msg
->major
, msg
->minor
, LTTNG_UST_ABI_MAJOR_VERSION
,
4271 LTTNG_UST_ABI_MINOR_VERSION
);
4274 ERR("UST app recv reg message failed with ret %d", ret
);
4279 msg
->pid
= (pid_t
) pid
;
4280 msg
->ppid
= (pid_t
) ppid
;
4281 msg
->uid
= (uid_t
) uid
;
4282 msg
->gid
= (gid_t
) gid
;
4289 * Return a ust app channel object using the application object and the channel
4290 * object descriptor has a key. If not found, NULL is returned. A RCU read side
4291 * lock MUST be acquired before calling this function.
4293 static struct ust_app_channel
*find_channel_by_objd(struct ust_app
*app
,
4296 struct lttng_ht_node_ulong
*node
;
4297 struct lttng_ht_iter iter
;
4298 struct ust_app_channel
*ua_chan
= NULL
;
4302 lttng_ht_lookup(app
->ust_objd
, (void *)((unsigned long) objd
), &iter
);
4303 node
= lttng_ht_iter_get_node_ulong(&iter
);
4305 DBG2("UST app channel find by objd %d not found", objd
);
4309 ua_chan
= caa_container_of(node
, struct ust_app_channel
, ust_objd_node
);
4316 * Reply to a register channel notification from an application on the notify
4317 * socket. The channel metadata is also created.
4319 * The session UST registry lock is acquired in this function.
4321 * On success 0 is returned else a negative value.
4323 static int reply_ust_register_channel(int sock
, int sobjd
, int cobjd
,
4324 size_t nr_fields
, struct ustctl_field
*fields
)
4326 int ret
, ret_code
= 0;
4327 uint32_t chan_id
, reg_count
;
4328 uint64_t chan_reg_key
;
4329 enum ustctl_channel_header type
;
4330 struct ust_app
*app
;
4331 struct ust_app_channel
*ua_chan
;
4332 struct ust_app_session
*ua_sess
;
4333 struct ust_registry_session
*registry
;
4334 struct ust_registry_channel
*chan_reg
;
4338 /* Lookup application. If not found, there is a code flow error. */
4339 app
= find_app_by_notify_sock(sock
);
4341 DBG("Application socket %d is being teardown. Abort event notify",
4344 goto error_rcu_unlock
;
4347 /* Lookup channel by UST object descriptor. Should always be found. */
4348 ua_chan
= find_channel_by_objd(app
, cobjd
);
4350 assert(ua_chan
->session
);
4351 ua_sess
= ua_chan
->session
;
4353 /* Get right session registry depending on the session buffer type. */
4354 registry
= get_session_registry(ua_sess
);
4357 /* Depending on the buffer type, a different channel key is used. */
4358 if (ua_sess
->buffer_type
== LTTNG_BUFFER_PER_UID
) {
4359 chan_reg_key
= ua_chan
->tracing_channel_id
;
4361 chan_reg_key
= ua_chan
->key
;
4364 pthread_mutex_lock(®istry
->lock
);
4366 chan_reg
= ust_registry_channel_find(registry
, chan_reg_key
);
4369 if (!chan_reg
->register_done
) {
4370 reg_count
= ust_registry_get_event_count(chan_reg
);
4371 if (reg_count
< 31) {
4372 type
= USTCTL_CHANNEL_HEADER_COMPACT
;
4374 type
= USTCTL_CHANNEL_HEADER_LARGE
;
4377 chan_reg
->nr_ctx_fields
= nr_fields
;
4378 chan_reg
->ctx_fields
= fields
;
4379 chan_reg
->header_type
= type
;
4381 /* Get current already assigned values. */
4382 type
= chan_reg
->header_type
;
4384 /* Channel id is set during the object creation. */
4385 chan_id
= chan_reg
->chan_id
;
4387 /* Append to metadata */
4388 if (!chan_reg
->metadata_dumped
) {
4389 ret_code
= ust_metadata_channel_statedump(registry
, chan_reg
);
4391 ERR("Error appending channel metadata (errno = %d)", ret_code
);
4397 DBG3("UST app replying to register channel key %" PRIu64
4398 " with id %u, type: %d, ret: %d", chan_reg_key
, chan_id
, type
,
4401 ret
= ustctl_reply_register_channel(sock
, chan_id
, type
, ret_code
);
4403 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
4404 ERR("UST app reply channel failed with ret %d", ret
);
4406 DBG3("UST app reply channel failed. Application died");
4411 /* This channel registry registration is completed. */
4412 chan_reg
->register_done
= 1;
4415 pthread_mutex_unlock(®istry
->lock
);
4422 * Add event to the UST channel registry. When the event is added to the
4423 * registry, the metadata is also created. Once done, this replies to the
4424 * application with the appropriate error code.
4426 * The session UST registry lock is acquired in the function.
4428 * On success 0 is returned else a negative value.
4430 static int add_event_ust_registry(int sock
, int sobjd
, int cobjd
, char *name
,
4431 char *sig
, size_t nr_fields
, struct ustctl_field
*fields
, int loglevel
,
4432 char *model_emf_uri
)
4435 uint32_t event_id
= 0;
4436 uint64_t chan_reg_key
;
4437 struct ust_app
*app
;
4438 struct ust_app_channel
*ua_chan
;
4439 struct ust_app_session
*ua_sess
;
4440 struct ust_registry_session
*registry
;
4444 /* Lookup application. If not found, there is a code flow error. */
4445 app
= find_app_by_notify_sock(sock
);
4447 DBG("Application socket %d is being teardown. Abort event notify",
4450 goto error_rcu_unlock
;
4453 /* Lookup channel by UST object descriptor. Should always be found. */
4454 ua_chan
= find_channel_by_objd(app
, cobjd
);
4456 assert(ua_chan
->session
);
4457 ua_sess
= ua_chan
->session
;
4459 registry
= get_session_registry(ua_sess
);
4462 if (ua_sess
->buffer_type
== LTTNG_BUFFER_PER_UID
) {
4463 chan_reg_key
= ua_chan
->tracing_channel_id
;
4465 chan_reg_key
= ua_chan
->key
;
4468 pthread_mutex_lock(®istry
->lock
);
4470 ret_code
= ust_registry_create_event(registry
, chan_reg_key
,
4471 sobjd
, cobjd
, name
, sig
, nr_fields
, fields
, loglevel
,
4472 model_emf_uri
, ua_sess
->buffer_type
, &event_id
);
4475 * The return value is returned to ustctl so in case of an error, the
4476 * application can be notified. In case of an error, it's important not to
4477 * return a negative error or else the application will get closed.
4479 ret
= ustctl_reply_register_event(sock
, event_id
, ret_code
);
4481 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
4482 ERR("UST app reply event failed with ret %d", ret
);
4484 DBG3("UST app reply event failed. Application died");
4487 * No need to wipe the create event since the application socket will
4488 * get close on error hence cleaning up everything by itself.
4493 DBG3("UST registry event %s with id %" PRId32
" added successfully",
4497 pthread_mutex_unlock(®istry
->lock
);
4504 * Handle application notification through the given notify socket.
4506 * Return 0 on success or else a negative value.
4508 int ust_app_recv_notify(int sock
)
4511 enum ustctl_notify_cmd cmd
;
4513 DBG3("UST app receiving notify from sock %d", sock
);
4515 ret
= ustctl_recv_notify(sock
, &cmd
);
4517 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
4518 ERR("UST app recv notify failed with ret %d", ret
);
4520 DBG3("UST app recv notify failed. Application died");
4526 case USTCTL_NOTIFY_CMD_EVENT
:
4528 int sobjd
, cobjd
, loglevel
;
4529 char name
[LTTNG_UST_SYM_NAME_LEN
], *sig
, *model_emf_uri
;
4531 struct ustctl_field
*fields
;
4533 DBG2("UST app ustctl register event received");
4535 ret
= ustctl_recv_register_event(sock
, &sobjd
, &cobjd
, name
, &loglevel
,
4536 &sig
, &nr_fields
, &fields
, &model_emf_uri
);
4538 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
4539 ERR("UST app recv event failed with ret %d", ret
);
4541 DBG3("UST app recv event failed. Application died");
4546 /* Add event to the UST registry coming from the notify socket. */
4547 ret
= add_event_ust_registry(sock
, sobjd
, cobjd
, name
, sig
, nr_fields
,
4548 fields
, loglevel
, model_emf_uri
);
4555 case USTCTL_NOTIFY_CMD_CHANNEL
:
4559 struct ustctl_field
*fields
;
4561 DBG2("UST app ustctl register channel received");
4563 ret
= ustctl_recv_register_channel(sock
, &sobjd
, &cobjd
, &nr_fields
,
4566 if (ret
!= -EPIPE
&& ret
!= -LTTNG_UST_ERR_EXITING
) {
4567 ERR("UST app recv channel failed with ret %d", ret
);
4569 DBG3("UST app recv channel failed. Application died");
4574 ret
= reply_ust_register_channel(sock
, sobjd
, cobjd
, nr_fields
,
4583 /* Should NEVER happen. */
4592 * Once the notify socket hangs up, this is called. First, it tries to find the
4593 * corresponding application. On failure, the call_rcu to close the socket is
4594 * executed. If an application is found, it tries to delete it from the notify
4595 * socket hash table. Whathever the result, it proceeds to the call_rcu.
4597 * Note that an object needs to be allocated here so on ENOMEM failure, the
4598 * call RCU is not done but the rest of the cleanup is.
4600 void ust_app_notify_sock_unregister(int sock
)
4603 struct lttng_ht_iter iter
;
4604 struct ust_app
*app
;
4605 struct ust_app_notify_sock_obj
*obj
;
4611 obj
= zmalloc(sizeof(*obj
));
4614 * An ENOMEM is kind of uncool. If this strikes we continue the
4615 * procedure but the call_rcu will not be called. In this case, we
4616 * accept the fd leak rather than possibly creating an unsynchronized
4617 * state between threads.
4619 * TODO: The notify object should be created once the notify socket is
4620 * registered and stored independantely from the ust app object. The
4621 * tricky part is to synchronize the teardown of the application and
4622 * this notify object. Let's keep that in mind so we can avoid this
4623 * kind of shenanigans with ENOMEM in the teardown path.
4630 DBG("UST app notify socket unregister %d", sock
);
4633 * Lookup application by notify socket. If this fails, this means that the
4634 * hash table delete has already been done by the application
4635 * unregistration process so we can safely close the notify socket in a
4638 app
= find_app_by_notify_sock(sock
);
4643 iter
.iter
.node
= &app
->notify_sock_n
.node
;
4646 * Whatever happens here either we fail or succeed, in both cases we have
4647 * to close the socket after a grace period to continue to the call RCU
4648 * here. If the deletion is successful, the application is not visible
4649 * anymore by other threads and is it fails it means that it was already
4650 * deleted from the hash table so either way we just have to close the
4653 (void) lttng_ht_del(ust_app_ht_by_notify_sock
, &iter
);
4659 * Close socket after a grace period to avoid for the socket to be reused
4660 * before the application object is freed creating potential race between
4661 * threads trying to add unique in the global hash table.
4664 call_rcu(&obj
->head
, close_notify_sock_rcu
);