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.
27 #include <sys/types.h>
30 #include <common/common.h>
31 #include <common/utils.h>
32 #include <common/trace-chunk.h>
33 #include <common/sessiond-comm/sessiond-comm.h>
34 #include <lttng/location-internal.h>
35 #include "lttng-sessiond.h"
40 #include "trace-ust.h"
43 struct ltt_session_destroy_notifier_element
{
44 ltt_session_destroy_notifier notifier
;
51 * No ltt_session.lock is taken here because those data structure are widely
52 * spread across the lttng-tools code base so before caling functions below
53 * that can read/write a session, the caller MUST acquire the session lock
54 * using session_lock() and session_unlock().
58 * Init tracing session list.
60 * Please see session.h for more explanation and correct usage of the list.
62 static struct ltt_session_list ltt_session_list
= {
63 .head
= CDS_LIST_HEAD_INIT(ltt_session_list
.head
),
64 .lock
= PTHREAD_MUTEX_INITIALIZER
,
65 .removal_cond
= PTHREAD_COND_INITIALIZER
,
69 /* These characters are forbidden in a session name. Used by validate_name. */
70 static const char *forbidden_name_chars
= "/";
72 /* Global hash table to keep the sessions, indexed by id. */
73 static struct lttng_ht
*ltt_sessions_ht_by_id
= NULL
;
76 * Validate the session name for forbidden characters.
78 * Return 0 on success else -1 meaning a forbidden char. has been found.
80 static int validate_name(const char *name
)
87 tmp_name
= strdup(name
);
94 tok
= strpbrk(tmp_name
, forbidden_name_chars
);
96 DBG("Session name %s contains a forbidden character", name
);
97 /* Forbidden character has been found. */
109 * Add a ltt_session structure to the global list.
111 * The caller MUST acquire the session list lock before.
112 * Returns the unique identifier for the session.
114 static uint64_t add_session_list(struct ltt_session
*ls
)
118 cds_list_add(&ls
->list
, <t_session_list
.head
);
119 return ltt_session_list
.next_uuid
++;
123 * Delete a ltt_session structure to the global list.
125 * The caller MUST acquire the session list lock before.
127 static void del_session_list(struct ltt_session
*ls
)
131 cds_list_del(&ls
->list
);
135 * Return a pointer to the session list.
137 struct ltt_session_list
*session_get_list(void)
139 return <t_session_list
;
143 * Returns once the session list is empty.
145 void session_list_wait_empty(void)
147 pthread_mutex_lock(<t_session_list
.lock
);
148 while (!cds_list_empty(<t_session_list
.head
)) {
149 pthread_cond_wait(<t_session_list
.removal_cond
,
150 <t_session_list
.lock
);
152 pthread_mutex_unlock(<t_session_list
.lock
);
156 * Acquire session list lock
158 void session_lock_list(void)
160 pthread_mutex_lock(<t_session_list
.lock
);
164 * Try to acquire session list lock
166 int session_trylock_list(void)
168 return pthread_mutex_trylock(<t_session_list
.lock
);
172 * Release session list lock
174 void session_unlock_list(void)
176 pthread_mutex_unlock(<t_session_list
.lock
);
180 * Get the session's consumer destination type.
182 * The caller must hold the session lock.
184 enum consumer_dst_type
session_get_consumer_destination_type(
185 const struct ltt_session
*session
)
188 * The output information is duplicated in both of those session types.
189 * Hence, it doesn't matter from which it is retrieved. However, it is
190 * possible for only one of them to be set.
192 return session
->kernel_session
?
193 session
->kernel_session
->consumer
->type
:
194 session
->ust_session
->consumer
->type
;
198 * Get the session's consumer network hostname.
199 * The caller must ensure that the destination is of type "net".
201 * The caller must hold the session lock.
203 const char *session_get_net_consumer_hostname(const struct ltt_session
*session
)
205 const char *hostname
= NULL
;
206 const struct consumer_output
*output
;
208 output
= session
->kernel_session
?
209 session
->kernel_session
->consumer
:
210 session
->ust_session
->consumer
;
213 * hostname is assumed to be the same for both control and data
216 switch (output
->dst
.net
.control
.dtype
) {
218 hostname
= output
->dst
.net
.control
.dst
.ipv4
;
221 hostname
= output
->dst
.net
.control
.dst
.ipv6
;
230 * Get the session's consumer network control and data ports.
231 * The caller must ensure that the destination is of type "net".
233 * The caller must hold the session lock.
235 void session_get_net_consumer_ports(const struct ltt_session
*session
,
236 uint16_t *control_port
, uint16_t *data_port
)
238 const struct consumer_output
*output
;
240 output
= session
->kernel_session
?
241 session
->kernel_session
->consumer
:
242 session
->ust_session
->consumer
;
243 *control_port
= output
->dst
.net
.control
.port
;
244 *data_port
= output
->dst
.net
.data
.port
;
248 * Get the location of the latest trace archive produced by a rotation.
250 * The caller must hold the session lock.
252 struct lttng_trace_archive_location
*session_get_trace_archive_location(
253 const struct ltt_session
*session
)
256 struct lttng_trace_archive_location
*location
= NULL
;
257 char *chunk_path
= NULL
;
259 if (session
->rotation_state
!= LTTNG_ROTATION_STATE_COMPLETED
||
260 !session
->last_archived_chunk_name
) {
264 ret
= asprintf(&chunk_path
, "%s/" DEFAULT_ARCHIVED_TRACE_CHUNKS_DIRECTORY
"/%s",
265 session_get_base_path(session
),
266 session
->last_archived_chunk_name
);
271 switch (session_get_consumer_destination_type(session
)) {
272 case CONSUMER_DST_LOCAL
:
273 location
= lttng_trace_archive_location_local_create(
276 case CONSUMER_DST_NET
:
278 const char *hostname
;
279 uint16_t control_port
, data_port
;
281 hostname
= session_get_net_consumer_hostname(session
);
282 session_get_net_consumer_ports(session
,
285 location
= lttng_trace_archive_location_relay_create(
287 LTTNG_TRACE_ARCHIVE_LOCATION_RELAY_PROTOCOL_TYPE_TCP
,
288 control_port
, data_port
, chunk_path
);
300 * Allocate the ltt_sessions_ht_by_id HT.
302 * The session list lock must be held.
304 int ltt_sessions_ht_alloc(void)
308 DBG("Allocating ltt_sessions_ht_by_id");
309 ltt_sessions_ht_by_id
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
310 if (!ltt_sessions_ht_by_id
) {
312 ERR("Failed to allocate ltt_sessions_ht_by_id");
320 * Destroy the ltt_sessions_ht_by_id HT.
322 * The session list lock must be held.
324 static void ltt_sessions_ht_destroy(void)
326 if (!ltt_sessions_ht_by_id
) {
329 ht_cleanup_push(ltt_sessions_ht_by_id
);
330 ltt_sessions_ht_by_id
= NULL
;
334 * Add a ltt_session to the ltt_sessions_ht_by_id.
335 * If unallocated, the ltt_sessions_ht_by_id HT is allocated.
336 * The session list lock must be held.
338 static void add_session_ht(struct ltt_session
*ls
)
344 if (!ltt_sessions_ht_by_id
) {
345 ret
= ltt_sessions_ht_alloc();
347 ERR("Error allocating the sessions HT");
351 lttng_ht_node_init_u64(&ls
->node
, ls
->id
);
352 lttng_ht_add_unique_u64(ltt_sessions_ht_by_id
, &ls
->node
);
359 * Test if ltt_sessions_ht_by_id is empty.
360 * Return 1 if empty, 0 if not empty.
361 * The session list lock must be held.
363 static int ltt_sessions_ht_empty(void)
367 if (!ltt_sessions_ht_by_id
) {
372 ret
= lttng_ht_get_count(ltt_sessions_ht_by_id
) ? 0 : 1;
378 * Remove a ltt_session from the ltt_sessions_ht_by_id.
379 * If empty, the ltt_sessions_ht_by_id HT is freed.
380 * The session list lock must be held.
382 static void del_session_ht(struct ltt_session
*ls
)
384 struct lttng_ht_iter iter
;
388 assert(ltt_sessions_ht_by_id
);
390 iter
.iter
.node
= &ls
->node
.node
;
391 ret
= lttng_ht_del(ltt_sessions_ht_by_id
, &iter
);
394 if (ltt_sessions_ht_empty()) {
395 DBG("Empty ltt_sessions_ht_by_id, destroying it");
396 ltt_sessions_ht_destroy();
401 * Acquire session lock
403 void session_lock(struct ltt_session
*session
)
407 pthread_mutex_lock(&session
->lock
);
411 * Release session lock
413 void session_unlock(struct ltt_session
*session
)
417 pthread_mutex_unlock(&session
->lock
);
421 int _session_set_trace_chunk_no_lock_check(struct ltt_session
*session
,
422 struct lttng_trace_chunk
*new_trace_chunk
,
423 struct lttng_trace_chunk
**_current_trace_chunk
)
426 unsigned int i
, refs_to_acquire
= 0, refs_acquired
= 0, refs_to_release
= 0;
427 struct cds_lfht_iter iter
;
428 struct consumer_socket
*socket
;
429 struct lttng_trace_chunk
*current_trace_chunk
;
431 enum lttng_trace_chunk_status chunk_status
;
435 * Ownership of current trace chunk is transferred to
436 * `current_trace_chunk`.
438 current_trace_chunk
= session
->current_trace_chunk
;
439 session
->current_trace_chunk
= NULL
;
440 if (session
->ust_session
) {
441 lttng_trace_chunk_put(
442 session
->ust_session
->current_trace_chunk
);
443 session
->ust_session
->current_trace_chunk
= NULL
;
445 if (session
->kernel_session
) {
446 lttng_trace_chunk_put(
447 session
->kernel_session
->current_trace_chunk
);
448 session
->kernel_session
->current_trace_chunk
= NULL
;
450 if (!new_trace_chunk
) {
454 chunk_status
= lttng_trace_chunk_get_id(new_trace_chunk
, &chunk_id
);
455 assert(chunk_status
== LTTNG_TRACE_CHUNK_STATUS_OK
);
458 refs_to_acquire
+= !!session
->ust_session
;
459 refs_to_acquire
+= !!session
->kernel_session
;
461 for (refs_acquired
= 0; refs_acquired
< refs_to_acquire
;
463 if (!lttng_trace_chunk_get(new_trace_chunk
)) {
464 ERR("Failed to acquire reference to new trace chunk of session \"%s\"",
470 if (session
->ust_session
) {
471 const uint64_t relayd_id
=
472 session
->ust_session
->consumer
->net_seq_index
;
473 const bool is_local_trace
=
474 session
->ust_session
->consumer
->type
==
477 session
->ust_session
->current_trace_chunk
= new_trace_chunk
;
478 if (is_local_trace
) {
479 enum lttng_error_code ret_error_code
;
481 ret_error_code
= ust_app_create_channel_subdirectories(
482 session
->ust_session
);
483 if (ret_error_code
!= LTTNG_OK
) {
484 ret
= -ret_error_code
;
488 cds_lfht_for_each_entry(
489 session
->ust_session
->consumer
->socks
->ht
,
490 &iter
, socket
, node
.node
) {
491 pthread_mutex_lock(socket
->lock
);
492 ret
= consumer_create_trace_chunk(socket
,
494 session
->id
, new_trace_chunk
);
495 pthread_mutex_unlock(socket
->lock
);
501 if (session
->kernel_session
) {
502 const uint64_t relayd_id
=
503 session
->kernel_session
->consumer
->net_seq_index
;
504 const bool is_local_trace
=
505 session
->kernel_session
->consumer
->type
==
508 session
->kernel_session
->current_trace_chunk
= new_trace_chunk
;
509 if (is_local_trace
) {
510 enum lttng_error_code ret_error_code
;
512 ret_error_code
= kernel_create_channel_subdirectories(
513 session
->kernel_session
);
514 if (ret_error_code
!= LTTNG_OK
) {
515 ret
= -ret_error_code
;
519 cds_lfht_for_each_entry(
520 session
->kernel_session
->consumer
->socks
->ht
,
521 &iter
, socket
, node
.node
) {
522 pthread_mutex_lock(socket
->lock
);
523 ret
= consumer_create_trace_chunk(socket
,
525 session
->id
, new_trace_chunk
);
526 pthread_mutex_unlock(socket
->lock
);
534 * Update local current trace chunk state last, only if all remote
535 * creations succeeded.
537 session
->current_trace_chunk
= new_trace_chunk
;
538 LTTNG_OPTIONAL_SET(&session
->most_recent_chunk_id
, chunk_id
);
540 if (_current_trace_chunk
) {
541 *_current_trace_chunk
= current_trace_chunk
;
542 current_trace_chunk
= NULL
;
546 lttng_trace_chunk_put(current_trace_chunk
);
549 if (session
->ust_session
) {
550 session
->ust_session
->current_trace_chunk
= NULL
;
552 if (session
->kernel_session
) {
553 session
->kernel_session
->current_trace_chunk
= NULL
;
556 * Release references taken in the case where all references could not
559 refs_to_release
= refs_to_acquire
- refs_acquired
;
560 for (i
= 0; i
< refs_to_release
; i
++) {
561 lttng_trace_chunk_put(new_trace_chunk
);
568 bool output_supports_trace_chunks(const struct consumer_output
*output
)
570 if (output
->type
== CONSUMER_DST_LOCAL
) {
573 if (output
->relay_major_version
> 2) {
575 } else if (output
->relay_major_version
== 2 &&
576 output
->relay_minor_version
>= 11) {
583 struct lttng_trace_chunk
*session_create_new_trace_chunk(
584 const struct ltt_session
*session
,
585 const struct consumer_output
*consumer_output_override
,
586 const char *session_base_path_override
,
587 const char *chunk_name_override
)
590 struct lttng_trace_chunk
*trace_chunk
= NULL
;
591 enum lttng_trace_chunk_status chunk_status
;
592 const time_t chunk_creation_ts
= time(NULL
);
594 const char *base_path
;
595 struct lttng_directory_handle session_output_directory
;
596 const struct lttng_credentials session_credentials
= {
600 uint64_t next_chunk_id
;
601 const struct consumer_output
*output
;
603 if (consumer_output_override
) {
604 output
= consumer_output_override
;
606 assert(session
->ust_session
|| session
->kernel_session
);
607 output
= session
->ust_session
?
608 session
->ust_session
->consumer
:
609 session
->kernel_session
->consumer
;
612 is_local_trace
= output
->type
== CONSUMER_DST_LOCAL
;
613 base_path
= session_base_path_override
? :
614 consumer_output_get_base_path(output
);
616 if (chunk_creation_ts
== (time_t) -1) {
617 PERROR("Failed to sample time while creation session \"%s\" trace chunk",
622 if (!output_supports_trace_chunks(output
)) {
625 next_chunk_id
= session
->most_recent_chunk_id
.is_set
?
626 session
->most_recent_chunk_id
.value
+ 1 : 0;
628 trace_chunk
= lttng_trace_chunk_create(next_chunk_id
,
634 if (chunk_name_override
) {
635 chunk_status
= lttng_trace_chunk_override_name(trace_chunk
,
636 chunk_name_override
);
637 if (chunk_status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
642 if (!is_local_trace
) {
644 * No need to set crendentials and output directory
645 * for remote trace chunks.
650 chunk_status
= lttng_trace_chunk_set_credentials(trace_chunk
,
651 &session_credentials
);
652 if (chunk_status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
656 DBG("Creating base output directory of session \"%s\" at %s",
657 session
->name
, base_path
);
658 ret
= utils_mkdir_recursive(base_path
, S_IRWXU
| S_IRWXG
,
659 session
->uid
, session
->gid
);
663 ret
= lttng_directory_handle_init(&session_output_directory
,
668 chunk_status
= lttng_trace_chunk_set_as_owner(trace_chunk
,
669 &session_output_directory
);
670 lttng_directory_handle_fini(&session_output_directory
);
671 if (chunk_status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
677 lttng_trace_chunk_put(trace_chunk
);
682 int session_close_trace_chunk(const struct ltt_session
*session
,
683 struct lttng_trace_chunk
*trace_chunk
,
684 const enum lttng_trace_chunk_command_type
*close_command
)
687 bool error_occurred
= false;
688 struct cds_lfht_iter iter
;
689 struct consumer_socket
*socket
;
690 enum lttng_trace_chunk_status chunk_status
;
691 const time_t chunk_close_timestamp
= time(NULL
);
694 chunk_status
= lttng_trace_chunk_set_close_command(
695 trace_chunk
, *close_command
);
696 if (chunk_status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
702 if (chunk_close_timestamp
== (time_t) -1) {
703 ERR("Failed to sample the close timestamp of the current trace chunk of session \"%s\"",
708 chunk_status
= lttng_trace_chunk_set_close_timestamp(trace_chunk
,
709 chunk_close_timestamp
);
710 if (chunk_status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
711 ERR("Failed to set the close timestamp of the current trace chunk of session \"%s\"",
717 if (session
->ust_session
) {
718 cds_lfht_for_each_entry(
719 session
->ust_session
->consumer
->socks
->ht
,
720 &iter
, socket
, node
.node
) {
721 pthread_mutex_lock(socket
->lock
);
722 ret
= consumer_close_trace_chunk(socket
,
723 session
->consumer
->net_seq_index
,
726 pthread_mutex_unlock(socket
->lock
);
728 ERR("Failed to close trace chunk on user space consumer");
729 error_occurred
= true;
733 if (session
->kernel_session
) {
734 cds_lfht_for_each_entry(
735 session
->kernel_session
->consumer
->socks
->ht
,
736 &iter
, socket
, node
.node
) {
737 pthread_mutex_lock(socket
->lock
);
738 ret
= consumer_close_trace_chunk(socket
,
739 session
->consumer
->net_seq_index
,
742 pthread_mutex_unlock(socket
->lock
);
744 ERR("Failed to close trace chunk on kernel consumer");
745 error_occurred
= true;
749 ret
= error_occurred
? -1 : 0;
755 * Set a session's current trace chunk.
757 * Must be called with the session lock held.
759 int session_set_trace_chunk(struct ltt_session
*session
,
760 struct lttng_trace_chunk
*new_trace_chunk
,
761 struct lttng_trace_chunk
**current_trace_chunk
)
763 ASSERT_LOCKED(session
->lock
);
764 return _session_set_trace_chunk_no_lock_check(session
, new_trace_chunk
,
765 current_trace_chunk
);
769 void session_notify_destruction(const struct ltt_session
*session
)
772 const size_t count
= lttng_dynamic_array_get_count(
773 &session
->destroy_notifiers
);
775 for (i
= 0; i
< count
; i
++) {
776 const struct ltt_session_destroy_notifier_element
*element
=
777 lttng_dynamic_array_get_element(
778 &session
->destroy_notifiers
, i
);
780 element
->notifier(session
, element
->user_data
);
785 void session_release(struct urcu_ref
*ref
)
788 struct ltt_ust_session
*usess
;
789 struct ltt_kernel_session
*ksess
;
790 struct ltt_session
*session
= container_of(ref
, typeof(*session
), ref
);
792 assert(!session
->chunk_being_archived
);
794 usess
= session
->ust_session
;
795 ksess
= session
->kernel_session
;
797 session_notify_destruction(session
);
798 lttng_dynamic_array_reset(&session
->destroy_notifiers
);
799 if (session
->current_trace_chunk
) {
800 ret
= session_close_trace_chunk(session
, session
->current_trace_chunk
, NULL
);
802 ERR("Failed to close the current trace chunk of session \"%s\" during its release",
805 ret
= _session_set_trace_chunk_no_lock_check(session
, NULL
, NULL
);
807 ERR("Failed to release the current trace chunk of session \"%s\" during its release",
812 /* Clean kernel session teardown */
813 kernel_destroy_session(ksess
);
814 session
->kernel_session
= NULL
;
816 /* UST session teardown */
818 /* Close any relayd session */
819 consumer_output_send_destroy_relayd(usess
->consumer
);
821 /* Destroy every UST application related to this session. */
822 ret
= ust_app_destroy_trace_all(usess
);
824 ERR("Error in ust_app_destroy_trace_all");
827 /* Clean up the rest. */
828 trace_ust_destroy_session(usess
);
829 session
->ust_session
= NULL
;
833 * Must notify the kernel thread here to update it's poll set in order to
834 * remove the channel(s)' fd just destroyed.
836 ret
= notify_thread_pipe(kernel_poll_pipe
[1]);
838 PERROR("write kernel poll pipe");
841 DBG("Destroying session %s (id %" PRIu64
")", session
->name
, session
->id
);
843 consumer_output_put(session
->consumer
);
844 snapshot_destroy(&session
->snapshot
);
846 pthread_mutex_destroy(&session
->lock
);
848 if (session
->published
) {
849 ASSERT_LOCKED(ltt_session_list
.lock
);
850 del_session_list(session
);
851 del_session_ht(session
);
852 pthread_cond_broadcast(<t_session_list
.removal_cond
);
854 free(session
->last_archived_chunk_name
);
859 * Acquire a reference to a session.
860 * This function may fail (return false); its return value must be checked.
862 bool session_get(struct ltt_session
*session
)
864 return urcu_ref_get_unless_zero(&session
->ref
);
868 * Release a reference to a session.
870 void session_put(struct ltt_session
*session
)
876 * The session list lock must be held as any session_put()
877 * may cause the removal of the session from the session_list.
879 ASSERT_LOCKED(ltt_session_list
.lock
);
880 assert(session
->ref
.refcount
);
881 urcu_ref_put(&session
->ref
, session_release
);
887 * This method does not immediately release/free the session as other
888 * components may still hold a reference to the session. However,
889 * the session should no longer be presented to the user.
891 * Releases the session list's reference to the session
892 * and marks it as destroyed. Iterations on the session list should be
893 * mindful of the "destroyed" flag.
895 void session_destroy(struct ltt_session
*session
)
897 assert(!session
->destroyed
);
898 session
->destroyed
= true;
899 session_put(session
);
902 int session_add_destroy_notifier(struct ltt_session
*session
,
903 ltt_session_destroy_notifier notifier
, void *user_data
)
905 const struct ltt_session_destroy_notifier_element element
= {
906 .notifier
= notifier
,
907 .user_data
= user_data
910 return lttng_dynamic_array_add_element(&session
->destroy_notifiers
,
915 * Return a ltt_session structure ptr that matches name. If no session found,
916 * NULL is returned. This must be called with the session list lock held using
917 * session_lock_list and session_unlock_list.
918 * A reference to the session is implicitly acquired by this function.
920 struct ltt_session
*session_find_by_name(const char *name
)
922 struct ltt_session
*iter
;
925 ASSERT_LOCKED(ltt_session_list
.lock
);
927 DBG2("Trying to find session by name %s", name
);
929 cds_list_for_each_entry(iter
, <t_session_list
.head
, list
) {
930 if (!strncmp(iter
->name
, name
, NAME_MAX
) &&
938 return session_get(iter
) ? iter
: NULL
;
942 * Return an ltt_session that matches the id. If no session is found,
943 * NULL is returned. This must be called with rcu_read_lock and
944 * session list lock held (to guarantee the lifetime of the session).
946 struct ltt_session
*session_find_by_id(uint64_t id
)
948 struct lttng_ht_node_u64
*node
;
949 struct lttng_ht_iter iter
;
950 struct ltt_session
*ls
;
952 ASSERT_LOCKED(ltt_session_list
.lock
);
954 if (!ltt_sessions_ht_by_id
) {
958 lttng_ht_lookup(ltt_sessions_ht_by_id
, &id
, &iter
);
959 node
= lttng_ht_iter_get_node_u64(&iter
);
963 ls
= caa_container_of(node
, struct ltt_session
, node
);
965 DBG3("Session %" PRIu64
" found by id.", id
);
966 return session_get(ls
) ? ls
: NULL
;
969 DBG3("Session %" PRIu64
" NOT found by id", id
);
974 * Create a new session and add it to the session list.
975 * Session list lock must be held by the caller.
977 enum lttng_error_code
session_create(const char *name
, uid_t uid
, gid_t gid
,
978 struct ltt_session
**out_session
)
981 enum lttng_error_code ret_code
;
982 struct ltt_session
*new_session
= NULL
;
984 ASSERT_LOCKED(ltt_session_list
.lock
);
986 struct ltt_session
*clashing_session
;
988 clashing_session
= session_find_by_name(name
);
989 if (clashing_session
) {
990 session_put(clashing_session
);
991 ret_code
= LTTNG_ERR_EXIST_SESS
;
995 new_session
= zmalloc(sizeof(struct ltt_session
));
997 PERROR("Failed to allocate an ltt_session structure");
998 ret_code
= LTTNG_ERR_NOMEM
;
1002 lttng_dynamic_array_init(&new_session
->destroy_notifiers
,
1003 sizeof(struct ltt_session_destroy_notifier_element
),
1005 urcu_ref_init(&new_session
->ref
);
1006 pthread_mutex_init(&new_session
->lock
, NULL
);
1008 new_session
->creation_time
= time(NULL
);
1009 if (new_session
->creation_time
== (time_t) -1) {
1010 PERROR("Failed to sample session creation time");
1011 ret_code
= LTTNG_ERR_SESSION_FAIL
;
1015 /* Create default consumer output. */
1016 new_session
->consumer
= consumer_create_output(CONSUMER_DST_LOCAL
);
1017 if (new_session
->consumer
== NULL
) {
1018 ret_code
= LTTNG_ERR_NOMEM
;
1023 ret
= lttng_strncpy(new_session
->name
, name
, sizeof(new_session
->name
));
1025 ret_code
= LTTNG_ERR_SESSION_INVALID_CHAR
;
1028 ret
= validate_name(name
);
1030 ret_code
= LTTNG_ERR_SESSION_INVALID_CHAR
;
1035 bool found_name
= false;
1037 struct tm
*timeinfo
;
1039 timeinfo
= localtime(&new_session
->creation_time
);
1041 ret_code
= LTTNG_ERR_SESSION_FAIL
;
1044 strftime(datetime
, sizeof(datetime
), "%Y%m%d-%H%M%S", timeinfo
);
1045 for (i
= 0; i
< INT_MAX
; i
++) {
1046 struct ltt_session
*clashing_session
;
1049 ret
= snprintf(new_session
->name
,
1050 sizeof(new_session
->name
),
1052 DEFAULT_SESSION_NAME
,
1055 ret
= snprintf(new_session
->name
,
1056 sizeof(new_session
->name
),
1058 DEFAULT_SESSION_NAME
, i
,
1061 if (ret
== -1 || ret
>= sizeof(new_session
->name
)) {
1063 * Null-terminate in case the name is used
1064 * in logging statements.
1066 new_session
->name
[sizeof(new_session
->name
) - 1] = '\0';
1067 ret_code
= LTTNG_ERR_SESSION_FAIL
;
1072 session_find_by_name(new_session
->name
);
1073 session_put(clashing_session
);
1074 if (!clashing_session
) {
1080 DBG("Generated session name \"%s\"", new_session
->name
);
1081 new_session
->has_auto_generated_name
= true;
1083 ERR("Failed to auto-generate a session name");
1084 ret_code
= LTTNG_ERR_SESSION_FAIL
;
1089 ret
= gethostname(new_session
->hostname
, sizeof(new_session
->hostname
));
1091 if (errno
== ENAMETOOLONG
) {
1092 new_session
->hostname
[sizeof(new_session
->hostname
) - 1] = '\0';
1093 ERR("Hostname exceeds the maximal permitted length and has been truncated to %s",
1094 new_session
->hostname
);
1096 ret_code
= LTTNG_ERR_SESSION_FAIL
;
1101 new_session
->uid
= uid
;
1102 new_session
->gid
= gid
;
1104 ret
= snapshot_init(&new_session
->snapshot
);
1106 ret_code
= LTTNG_ERR_NOMEM
;
1110 new_session
->rotation_state
= LTTNG_ROTATION_STATE_NO_ROTATION
;
1112 /* Add new session to the session list. */
1113 new_session
->id
= add_session_list(new_session
);
1116 * Add the new session to the ltt_sessions_ht_by_id.
1117 * No ownership is taken by the hash table; it is merely
1118 * a wrapper around the session list used for faster access
1121 add_session_ht(new_session
);
1122 new_session
->published
= true;
1125 * Consumer is left to NULL since the create_session_uri command will
1126 * set it up and, if valid, assign it to the session.
1128 DBG("Tracing session %s created with ID %" PRIu64
" by uid = %d, gid = %d",
1129 new_session
->name
, new_session
->id
, new_session
->uid
,
1131 ret_code
= LTTNG_OK
;
1134 (void) session_get(new_session
);
1135 *out_session
= new_session
;
1139 session_put(new_session
);
1145 * Check if the UID or GID match the session. Root user has access to all
1148 int session_access_ok(struct ltt_session
*session
, uid_t uid
, gid_t gid
)
1152 if (uid
!= session
->uid
&& gid
!= session
->gid
&& uid
!= 0) {
1160 * Set a session's rotation state and reset all associated state.
1162 * This function resets the rotation state (check timers, pending
1163 * flags, etc.) and sets the result of the last rotation. The result
1164 * can be queries by a liblttng-ctl client.
1166 * Be careful of the result passed to this function. For instance,
1167 * on failure to launch a rotation, a client will expect the rotation
1168 * state to be set to "NO_ROTATION". If an error occured while the
1169 * rotation was "ONGOING", result should be set to "ERROR", which will
1170 * allow a client to report it.
1172 * Must be called with the session and session_list locks held.
1174 int session_reset_rotation_state(struct ltt_session
*session
,
1175 enum lttng_rotation_state result
)
1179 ASSERT_LOCKED(ltt_session_list
.lock
);
1180 ASSERT_LOCKED(session
->lock
);
1182 session
->rotation_state
= result
;
1183 if (session
->rotation_pending_check_timer_enabled
) {
1184 ret
= timer_session_rotation_pending_check_stop(session
);
1186 if (session
->chunk_being_archived
) {
1188 enum lttng_trace_chunk_status chunk_status
;
1190 chunk_status
= lttng_trace_chunk_get_id(
1191 session
->chunk_being_archived
,
1193 assert(chunk_status
== LTTNG_TRACE_CHUNK_STATUS_OK
);
1194 LTTNG_OPTIONAL_SET(&session
->last_archived_chunk_id
,
1196 lttng_trace_chunk_put(session
->chunk_being_archived
);
1197 session
->chunk_being_archived
= NULL
;