2 * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 * SPDX-License-Identifier: GPL-2.0-only
8 #include "lttng/action/action.h"
9 #include "lttng/trigger/trigger-internal.hpp"
12 #include <urcu/rculfhash.h>
14 #include <common/defaults.hpp>
15 #include <common/error.hpp>
16 #include <common/futex.hpp>
17 #include <common/unix.hpp>
18 #include <common/dynamic-buffer.hpp>
19 #include <common/hashtable/utils.hpp>
20 #include <common/sessiond-comm/sessiond-comm.hpp>
21 #include <common/macros.hpp>
22 #include <lttng/condition/condition.h>
23 #include <lttng/action/action-internal.hpp>
24 #include <lttng/action/list-internal.hpp>
25 #include <lttng/domain-internal.hpp>
26 #include <lttng/notification/notification-internal.hpp>
27 #include <lttng/condition/condition-internal.hpp>
28 #include <lttng/condition/buffer-usage-internal.hpp>
29 #include <lttng/condition/session-consumed-size-internal.hpp>
30 #include <lttng/condition/session-rotation-internal.hpp>
31 #include <lttng/condition/event-rule-matches-internal.hpp>
32 #include <lttng/domain-internal.hpp>
33 #include <lttng/notification/channel-internal.hpp>
34 #include <lttng/trigger/trigger-internal.hpp>
35 #include <lttng/event-rule/event-rule-internal.hpp>
36 #include <lttng/location-internal.hpp>
43 #include "condition-internal.hpp"
44 #include "event-notifier-error-accounting.hpp"
45 #include "notification-thread.hpp"
46 #include "notification-thread-events.hpp"
47 #include "notification-thread-commands.hpp"
48 #include "lttng-sessiond.hpp"
51 #define CLIENT_POLL_EVENTS_IN (LPOLLIN | LPOLLERR | LPOLLHUP | LPOLLRDHUP)
52 #define CLIENT_POLL_EVENTS_IN_OUT (CLIENT_POLL_EVENTS_IN | LPOLLOUT)
54 /* The tracers currently limit the capture size to PIPE_BUF (4kb on linux). */
55 #define MAX_CAPTURE_SIZE (PIPE_BUF)
57 enum lttng_object_type
{
58 LTTNG_OBJECT_TYPE_UNKNOWN
,
59 LTTNG_OBJECT_TYPE_NONE
,
60 LTTNG_OBJECT_TYPE_CHANNEL
,
61 LTTNG_OBJECT_TYPE_SESSION
,
64 struct lttng_channel_trigger_list
{
65 struct channel_key channel_key
;
66 /* List of struct lttng_trigger_list_element. */
67 struct cds_list_head list
;
68 /* Node in the channel_triggers_ht */
69 struct cds_lfht_node channel_triggers_ht_node
;
70 /* call_rcu delayed reclaim. */
71 struct rcu_head rcu_node
;
75 * List of triggers applying to a given session.
78 * - lttng_session_trigger_list_create()
79 * - lttng_session_trigger_list_build()
80 * - lttng_session_trigger_list_destroy()
81 * - lttng_session_trigger_list_add()
83 struct lttng_session_trigger_list
{
85 /* List of struct lttng_trigger_list_element. */
86 struct cds_list_head list
;
87 /* Node in the session_triggers_ht */
88 struct cds_lfht_node session_triggers_ht_node
;
90 * Weak reference to the notification system's session triggers
93 * The session trigger list structure structure is owned by
94 * the session's session_info.
96 * The session_info is kept alive the the channel_infos holding a
97 * reference to it (reference counting). When those channels are
98 * destroyed (at runtime or on teardown), the reference they hold
99 * to the session_info are released. On destruction of session_info,
100 * session_info_destroy() will remove the list of triggers applying
101 * to this session from the notification system's state.
103 * This implies that the session_triggers_ht must be destroyed
104 * after the channels.
106 struct cds_lfht
*session_triggers_ht
;
107 /* Used for delayed RCU reclaim. */
108 struct rcu_head rcu_node
;
112 struct lttng_trigger_list_element
{
113 /* No ownership of the trigger object is assumed. */
114 struct lttng_trigger
*trigger
;
115 struct cds_list_head node
;
118 struct lttng_trigger_ht_element
{
119 struct lttng_trigger
*trigger
;
120 struct cds_lfht_node node
;
121 struct cds_lfht_node node_by_name_uid
;
122 struct cds_list_head client_list_trigger_node
;
123 /* call_rcu delayed reclaim. */
124 struct rcu_head rcu_node
;
127 struct lttng_condition_list_element
{
128 struct lttng_condition
*condition
;
129 struct cds_list_head node
;
132 struct channel_state_sample
{
133 struct channel_key key
;
134 struct cds_lfht_node channel_state_ht_node
;
135 uint64_t highest_usage
;
136 uint64_t lowest_usage
;
137 /* call_rcu delayed reclaim. */
138 struct rcu_head rcu_node
;
142 static unsigned long hash_channel_key(struct channel_key
*key
);
143 static int evaluate_buffer_condition(const struct lttng_condition
*condition
,
144 struct lttng_evaluation
**evaluation
,
145 const struct notification_thread_state
*state
,
146 const struct channel_state_sample
*previous_sample
,
147 const struct channel_state_sample
*latest_sample
,
148 struct channel_info
*channel_info
);
150 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
151 const struct lttng_evaluation
*evaluation
,
152 struct notification_client_list
*client_list
,
153 struct notification_thread_state
*state
,
154 uid_t channel_uid
, gid_t channel_gid
);
157 /* session_info API */
159 void session_info_destroy(void *_data
);
161 void session_info_get(struct session_info
*session_info
);
163 void session_info_put(struct session_info
*session_info
);
165 struct session_info
*session_info_create(uint64_t id
,
169 struct lttng_session_trigger_list
*trigger_list
,
170 struct cds_lfht
*sessions_ht
);
171 static void session_info_add_channel(
172 struct session_info
*session_info
, struct channel_info
*channel_info
);
174 void session_info_remove_channel(struct session_info
*session_info
,
175 struct channel_info
*channel_info
);
177 /* lttng_session_trigger_list API */
179 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
180 const char *session_name
,
181 struct cds_lfht
*session_triggers_ht
);
183 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
184 const struct notification_thread_state
*state
,
185 const char *session_name
);
187 void lttng_session_trigger_list_destroy(
188 struct lttng_session_trigger_list
*list
);
190 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
191 struct lttng_trigger
*trigger
);
194 int client_handle_transmission_status(
195 struct notification_client
*client
,
196 enum client_transmission_status transmission_status
,
197 struct notification_thread_state
*state
);
200 int handle_one_event_notifier_notification(
201 struct notification_thread_state
*state
,
202 int pipe
, enum lttng_domain_type domain
);
205 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
);
208 int match_client_socket(struct cds_lfht_node
*node
, const void *key
)
210 /* This double-cast is intended to supress pointer-to-cast warning. */
211 const int socket
= (int) (intptr_t) key
;
212 const struct notification_client
*client
= caa_container_of(node
,
213 struct notification_client
, client_socket_ht_node
);
215 return client
->socket
== socket
;
219 int match_client_id(struct cds_lfht_node
*node
, const void *key
)
221 /* This double-cast is intended to supress pointer-to-cast warning. */
222 const notification_client_id id
= *((notification_client_id
*) key
);
223 const struct notification_client
*client
= lttng::utils::container_of(
224 node
, ¬ification_client::client_id_ht_node
);
226 return client
->id
== id
;
230 int match_channel_trigger_list(struct cds_lfht_node
*node
, const void *key
)
232 struct channel_key
*channel_key
= (struct channel_key
*) key
;
233 struct lttng_channel_trigger_list
*trigger_list
;
235 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
236 channel_triggers_ht_node
);
238 return !!((channel_key
->key
== trigger_list
->channel_key
.key
) &&
239 (channel_key
->domain
== trigger_list
->channel_key
.domain
));
243 int match_session_trigger_list(struct cds_lfht_node
*node
, const void *key
)
245 const char *session_name
= (const char *) key
;
246 struct lttng_session_trigger_list
*trigger_list
;
248 trigger_list
= caa_container_of(node
, struct lttng_session_trigger_list
,
249 session_triggers_ht_node
);
251 return !!(strcmp(trigger_list
->session_name
, session_name
) == 0);
255 int match_channel_state_sample(struct cds_lfht_node
*node
, const void *key
)
257 struct channel_key
*channel_key
= (struct channel_key
*) key
;
258 struct channel_state_sample
*sample
;
260 sample
= caa_container_of(node
, struct channel_state_sample
,
261 channel_state_ht_node
);
263 return !!((channel_key
->key
== sample
->key
.key
) &&
264 (channel_key
->domain
== sample
->key
.domain
));
268 int match_channel_info(struct cds_lfht_node
*node
, const void *key
)
270 struct channel_key
*channel_key
= (struct channel_key
*) key
;
271 struct channel_info
*channel_info
;
273 channel_info
= caa_container_of(node
, struct channel_info
,
276 return !!((channel_key
->key
== channel_info
->key
.key
) &&
277 (channel_key
->domain
== channel_info
->key
.domain
));
281 int match_trigger(struct cds_lfht_node
*node
, const void *key
)
283 struct lttng_trigger
*trigger_key
= (struct lttng_trigger
*) key
;
284 struct lttng_trigger_ht_element
*trigger_ht_element
;
286 trigger_ht_element
= caa_container_of(node
, struct lttng_trigger_ht_element
,
289 return !!lttng_trigger_is_equal(trigger_key
, trigger_ht_element
->trigger
);
293 int match_trigger_token(struct cds_lfht_node
*node
, const void *key
)
295 const uint64_t *_key
= (uint64_t *) key
;
296 struct notification_trigger_tokens_ht_element
*element
;
298 element
= caa_container_of(node
,
299 struct notification_trigger_tokens_ht_element
, node
);
300 return *_key
== element
->token
;
304 int match_client_list_condition(struct cds_lfht_node
*node
, const void *key
)
306 struct lttng_condition
*condition_key
= (struct lttng_condition
*) key
;
307 struct notification_client_list
*client_list
;
308 const struct lttng_condition
*condition
;
310 LTTNG_ASSERT(condition_key
);
312 client_list
= caa_container_of(node
, struct notification_client_list
,
313 notification_trigger_clients_ht_node
);
314 condition
= client_list
->condition
;
316 return !!lttng_condition_is_equal(condition_key
, condition
);
320 int match_session_info(struct cds_lfht_node
*node
, const void *key
)
322 const auto session_id
= *((uint64_t *) key
);
323 const auto *session_info
= lttng::utils::container_of(
324 node
, &session_info::sessions_ht_node
);
326 return session_id
== session_info
->id
;
330 unsigned long hash_session_info_id(uint64_t id
)
332 return hash_key_u64(&id
, lttng_ht_seed
);
336 unsigned long hash_session_info(const struct session_info
*session_info
)
338 return hash_session_info_id(session_info
->id
);
342 struct session_info
*get_session_info_by_id(
343 const struct notification_thread_state
*state
, uint64_t id
)
345 struct cds_lfht_iter iter
;
346 struct cds_lfht_node
*node
;
347 lttng::urcu::read_lock_guard read_lock_guard
;
349 cds_lfht_lookup(state
->sessions_ht
,
350 hash_session_info_id(id
),
354 node
= cds_lfht_iter_get_node(&iter
);
357 auto session_info
= lttng::utils::container_of(node
, &session_info::sessions_ht_node
);
359 session_info_get(session_info
);
367 struct session_info
*get_session_info_by_name(
368 const struct notification_thread_state
*state
, const char *name
)
371 const auto found
= sample_session_id_by_name(name
, &session_id
);
373 return found
? get_session_info_by_id(state
, session_id
) : NULL
;
377 const char *notification_command_type_str(
378 enum notification_thread_command_type type
)
381 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
382 return "REGISTER_TRIGGER";
383 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
384 return "UNREGISTER_TRIGGER";
385 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
386 return "ADD_CHANNEL";
387 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
388 return "REMOVE_CHANNEL";
389 case NOTIFICATION_COMMAND_TYPE_ADD_SESSION
:
390 return "ADD_SESSION";
391 case NOTIFICATION_COMMAND_TYPE_REMOVE_SESSION
:
392 return "REMOVE_SESSION";
393 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
394 return "SESSION_ROTATION_ONGOING";
395 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
396 return "SESSION_ROTATION_COMPLETED";
397 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
398 return "ADD_TRACER_EVENT_SOURCE";
399 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
400 return "REMOVE_TRACER_EVENT_SOURCE";
401 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
402 return "LIST_TRIGGERS";
403 case NOTIFICATION_COMMAND_TYPE_GET_TRIGGER
:
404 return "GET_TRIGGER";
405 case NOTIFICATION_COMMAND_TYPE_QUIT
:
407 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
408 return "CLIENT_COMMUNICATION_UPDATE";
415 * Match trigger based on name and credentials only.
416 * Name duplication is NOT allowed for the same uid.
419 int match_trigger_by_name_uid(struct cds_lfht_node
*node
,
423 const char *element_trigger_name
;
424 const char *key_name
;
425 enum lttng_trigger_status status
;
426 const struct lttng_credentials
*key_creds
;
427 const struct lttng_credentials
*node_creds
;
428 const struct lttng_trigger
*trigger_key
=
429 (const struct lttng_trigger
*) key
;
430 const struct lttng_trigger_ht_element
*trigger_ht_element
=
431 caa_container_of(node
,
432 struct lttng_trigger_ht_element
,
435 status
= lttng_trigger_get_name(trigger_ht_element
->trigger
,
436 &element_trigger_name
);
437 element_trigger_name
= status
== LTTNG_TRIGGER_STATUS_OK
?
438 element_trigger_name
: NULL
;
440 status
= lttng_trigger_get_name(trigger_key
, &key_name
);
441 key_name
= status
== LTTNG_TRIGGER_STATUS_OK
? key_name
: NULL
;
445 * Consider null names as not equal. This is to maintain backwards
446 * compatibility with pre-2.13 anonymous triggers. Multiples anonymous
447 * triggers are allowed for a given user.
449 if (!element_trigger_name
|| !key_name
) {
453 if (strcmp(element_trigger_name
, key_name
) != 0) {
457 /* Compare the owners' UIDs. */
458 key_creds
= lttng_trigger_get_credentials(trigger_key
);
459 node_creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
461 match
= lttng_credentials_is_equal_uid(key_creds
, node_creds
);
468 * Hash trigger based on name and credentials only.
471 unsigned long hash_trigger_by_name_uid(const struct lttng_trigger
*trigger
)
473 unsigned long hash
= 0;
474 const struct lttng_credentials
*trigger_creds
;
475 const char *trigger_name
;
476 enum lttng_trigger_status status
;
478 status
= lttng_trigger_get_name(trigger
, &trigger_name
);
479 if (status
== LTTNG_TRIGGER_STATUS_OK
) {
480 hash
= hash_key_str(trigger_name
, lttng_ht_seed
);
483 trigger_creds
= lttng_trigger_get_credentials(trigger
);
484 hash
^= hash_key_ulong((void *) (unsigned long) LTTNG_OPTIONAL_GET(trigger_creds
->uid
),
491 unsigned long hash_channel_key(struct channel_key
*key
)
493 unsigned long key_hash
= hash_key_u64(&key
->key
, lttng_ht_seed
);
494 unsigned long domain_hash
= hash_key_ulong(
495 (void *) (unsigned long) key
->domain
, lttng_ht_seed
);
497 return key_hash
^ domain_hash
;
501 unsigned long hash_client_socket(int socket
)
503 return hash_key_ulong((void *) (unsigned long) socket
, lttng_ht_seed
);
507 unsigned long hash_client_id(notification_client_id id
)
509 return hash_key_u64(&id
, lttng_ht_seed
);
513 * Get the type of object to which a given condition applies. Bindings let
514 * the notification system evaluate a trigger's condition when a given
515 * object's state is updated.
517 * For instance, a condition bound to a channel will be evaluated everytime
518 * the channel's state is changed by a channel monitoring sample.
521 enum lttng_object_type
get_condition_binding_object(
522 const struct lttng_condition
*condition
)
524 switch (lttng_condition_get_type(condition
)) {
525 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
526 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
527 return LTTNG_OBJECT_TYPE_CHANNEL
;
528 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
529 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
530 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
531 return LTTNG_OBJECT_TYPE_SESSION
;
532 case LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES
:
533 return LTTNG_OBJECT_TYPE_NONE
;
535 return LTTNG_OBJECT_TYPE_UNKNOWN
;
540 void free_channel_info_rcu(struct rcu_head
*node
)
542 free(lttng::utils::container_of(node
, &channel_info::rcu_node
));
546 void channel_info_destroy(struct channel_info
*channel_info
)
552 if (channel_info
->session_info
) {
553 session_info_remove_channel(channel_info
->session_info
,
555 session_info_put(channel_info
->session_info
);
557 if (channel_info
->name
) {
558 free(channel_info
->name
);
560 call_rcu(&channel_info
->rcu_node
, free_channel_info_rcu
);
564 void free_session_info_rcu(struct rcu_head
*node
)
566 free(lttng::utils::container_of(node
, &session_info::rcu_node
));
569 /* Don't call directly, use the ref-counting mechanism. */
571 void session_info_destroy(void *_data
)
573 struct session_info
*session_info
= (struct session_info
*) _data
;
576 LTTNG_ASSERT(session_info
);
577 if (session_info
->channel_infos_ht
) {
578 ret
= cds_lfht_destroy(session_info
->channel_infos_ht
, NULL
);
580 ERR("Failed to destroy channel information hash table");
583 lttng_session_trigger_list_destroy(session_info
->trigger_list
);
586 cds_lfht_del(session_info
->sessions_ht
,
587 &session_info
->sessions_ht_node
);
589 free(session_info
->name
);
590 lttng_trace_archive_location_put(session_info
->last_state_sample
.rotation
.location
);
591 call_rcu(&session_info
->rcu_node
, free_session_info_rcu
);
595 void session_info_get(struct session_info
*session_info
)
600 lttng_ref_get(&session_info
->ref
);
604 void session_info_put(struct session_info
*session_info
)
609 lttng_ref_put(&session_info
->ref
);
613 struct session_info
*session_info_create(uint64_t id
,
617 struct lttng_session_trigger_list
*trigger_list
,
618 struct cds_lfht
*sessions_ht
)
620 struct session_info
*session_info
;
624 session_info
= zmalloc
<struct session_info
>();
629 lttng_ref_init(&session_info
->ref
, session_info_destroy
);
631 session_info
->channel_infos_ht
= cds_lfht_new(DEFAULT_HT_SIZE
,
632 1, 0, CDS_LFHT_AUTO_RESIZE
| CDS_LFHT_ACCOUNTING
, NULL
);
633 if (!session_info
->channel_infos_ht
) {
637 cds_lfht_node_init(&session_info
->sessions_ht_node
);
638 session_info
->id
= id
;
639 session_info
->name
= strdup(name
);
640 if (!session_info
->name
) {
644 session_info
->uid
= uid
;
645 session_info
->gid
= gid
;
646 session_info
->trigger_list
= trigger_list
;
647 session_info
->sessions_ht
= sessions_ht
;
651 session_info_put(session_info
);
656 void session_info_add_channel(struct session_info
*session_info
,
657 struct channel_info
*channel_info
)
660 cds_lfht_add(session_info
->channel_infos_ht
,
661 hash_channel_key(&channel_info
->key
),
662 &channel_info
->session_info_channels_ht_node
);
667 void session_info_remove_channel(struct session_info
*session_info
,
668 struct channel_info
*channel_info
)
671 cds_lfht_del(session_info
->channel_infos_ht
,
672 &channel_info
->session_info_channels_ht_node
);
677 struct channel_info
*channel_info_create(const char *channel_name
,
678 struct channel_key
*channel_key
, uint64_t channel_capacity
,
679 struct session_info
*session_info
)
681 struct channel_info
*channel_info
= zmalloc
<struct channel_info
>();
687 cds_lfht_node_init(&channel_info
->channels_ht_node
);
688 cds_lfht_node_init(&channel_info
->session_info_channels_ht_node
);
689 memcpy(&channel_info
->key
, channel_key
, sizeof(*channel_key
));
690 channel_info
->capacity
= channel_capacity
;
692 channel_info
->name
= strdup(channel_name
);
693 if (!channel_info
->name
) {
698 * Set the references between session and channel infos:
699 * - channel_info holds a strong reference to session_info
700 * - session_info holds a weak reference to channel_info
702 session_info_get(session_info
);
703 session_info_add_channel(session_info
, channel_info
);
704 channel_info
->session_info
= session_info
;
708 channel_info_destroy(channel_info
);
712 bool notification_client_list_get(struct notification_client_list
*list
)
714 return urcu_ref_get_unless_zero(&list
->ref
);
718 void free_notification_client_list_rcu(struct rcu_head
*node
)
720 free(caa_container_of(node
, struct notification_client_list
,
725 void notification_client_list_release(struct urcu_ref
*list_ref
)
727 struct notification_client_list
*list
=
728 lttng::utils::container_of(list_ref
, ¬ification_client_list::ref
);
729 struct notification_client_list_element
*client_list_element
, *tmp
;
731 lttng_condition_put(list
->condition
);
733 if (list
->notification_trigger_clients_ht
) {
736 cds_lfht_del(list
->notification_trigger_clients_ht
,
737 &list
->notification_trigger_clients_ht_node
);
739 list
->notification_trigger_clients_ht
= NULL
;
741 cds_list_for_each_entry_safe(client_list_element
, tmp
,
742 &list
->clients_list
, node
) {
743 free(client_list_element
);
746 LTTNG_ASSERT(cds_list_empty(&list
->triggers_list
));
748 pthread_mutex_destroy(&list
->lock
);
749 call_rcu(&list
->rcu_node
, free_notification_client_list_rcu
);
753 bool condition_applies_to_client(const struct lttng_condition
*condition
,
754 struct notification_client
*client
)
756 bool applies
= false;
757 struct lttng_condition_list_element
*condition_list_element
;
759 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
,
761 applies
= lttng_condition_is_equal(
762 condition_list_element
->condition
,
773 struct notification_client_list
*notification_client_list_create(
774 struct notification_thread_state
*state
,
775 const struct lttng_condition
*condition
)
777 struct notification_client
*client
;
778 struct cds_lfht_iter iter
;
779 struct notification_client_list
*client_list
;
781 client_list
= zmalloc
<notification_client_list
>();
783 PERROR("Failed to allocate notification client list");
787 pthread_mutex_init(&client_list
->lock
, NULL
);
789 * The trigger that owns the condition has the first reference to this
792 urcu_ref_init(&client_list
->ref
);
793 cds_lfht_node_init(&client_list
->notification_trigger_clients_ht_node
);
794 CDS_INIT_LIST_HEAD(&client_list
->clients_list
);
795 CDS_INIT_LIST_HEAD(&client_list
->triggers_list
);
798 * Create a copy of the condition so that it's independent of any
799 * trigger. The client list may outlive the trigger object (which owns
800 * the condition) that is used to create it.
802 client_list
->condition
= lttng_condition_copy(condition
);
804 /* Build a list of clients to which this new condition applies. */
805 cds_lfht_for_each_entry (state
->client_socket_ht
, &iter
, client
,
806 client_socket_ht_node
) {
807 struct notification_client_list_element
*client_list_element
;
809 if (!condition_applies_to_client(condition
, client
)) {
813 client_list_element
= zmalloc
<notification_client_list_element
>();
814 if (!client_list_element
) {
815 goto error_put_client_list
;
818 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
819 client_list_element
->client
= client
;
820 cds_list_add(&client_list_element
->node
, &client_list
->clients_list
);
823 client_list
->notification_trigger_clients_ht
=
824 state
->notification_trigger_clients_ht
;
828 * Add the client list to the global list of client list.
830 cds_lfht_add_unique(state
->notification_trigger_clients_ht
,
831 lttng_condition_hash(client_list
->condition
),
832 match_client_list_condition
,
833 client_list
->condition
,
834 &client_list
->notification_trigger_clients_ht_node
);
838 error_put_client_list
:
839 notification_client_list_put(client_list
);
846 void notification_client_list_put(struct notification_client_list
*list
)
851 return urcu_ref_put(&list
->ref
, notification_client_list_release
);
854 /* Provides a reference to the returned list. */
856 struct notification_client_list
*get_client_list_from_condition(
857 struct notification_thread_state
*state
,
858 const struct lttng_condition
*condition
)
860 struct cds_lfht_node
*node
;
861 struct cds_lfht_iter iter
;
862 struct notification_client_list
*list
= NULL
;
865 cds_lfht_lookup(state
->notification_trigger_clients_ht
,
866 lttng_condition_hash(condition
),
867 match_client_list_condition
,
870 node
= cds_lfht_iter_get_node(&iter
);
872 list
= lttng::utils::container_of(node
,
873 ¬ification_client_list::notification_trigger_clients_ht_node
);
874 list
= notification_client_list_get(list
) ? list
: NULL
;
882 int evaluate_channel_condition_for_client(
883 const struct lttng_condition
*condition
,
884 struct notification_thread_state
*state
,
885 struct lttng_evaluation
**evaluation
,
886 uid_t
*session_uid
, gid_t
*session_gid
)
889 struct cds_lfht_iter iter
;
890 struct cds_lfht_node
*node
;
891 struct channel_info
*channel_info
= NULL
;
892 struct channel_key
*channel_key
= NULL
;
893 struct channel_state_sample
*last_sample
= NULL
;
894 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
898 /* Find the channel associated with the condition. */
899 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
,
900 channel_trigger_list
, channel_triggers_ht_node
) {
901 struct lttng_trigger_list_element
*element
;
903 cds_list_for_each_entry(element
, &channel_trigger_list
->list
, node
) {
904 const struct lttng_condition
*current_condition
=
905 lttng_trigger_get_const_condition(
908 LTTNG_ASSERT(current_condition
);
909 if (!lttng_condition_is_equal(condition
,
910 current_condition
)) {
914 /* Found the trigger, save the channel key. */
915 channel_key
= &channel_trigger_list
->channel_key
;
919 /* The channel key was found stop iteration. */
925 /* No channel found; normal exit. */
926 DBG("No known channel associated with newly subscribed-to condition");
931 /* Fetch channel info for the matching channel. */
932 cds_lfht_lookup(state
->channels_ht
,
933 hash_channel_key(channel_key
),
937 node
= cds_lfht_iter_get_node(&iter
);
939 channel_info
= caa_container_of(node
, struct channel_info
,
942 /* Retrieve the channel's last sample, if it exists. */
943 cds_lfht_lookup(state
->channel_state_ht
,
944 hash_channel_key(channel_key
),
945 match_channel_state_sample
,
948 node
= cds_lfht_iter_get_node(&iter
);
950 last_sample
= caa_container_of(node
,
951 struct channel_state_sample
,
952 channel_state_ht_node
);
954 /* Nothing to evaluate, no sample was ever taken. Normal exit */
955 DBG("No channel sample associated with newly subscribed-to condition");
960 ret
= evaluate_buffer_condition(condition
, evaluation
, state
,
964 WARN("Fatal error occurred while evaluating a newly subscribed-to condition");
968 *session_uid
= channel_info
->session_info
->uid
;
969 *session_gid
= channel_info
->session_info
->gid
;
976 const char *get_condition_session_name(const struct lttng_condition
*condition
)
978 const char *session_name
= NULL
;
979 enum lttng_condition_status status
;
981 switch (lttng_condition_get_type(condition
)) {
982 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
983 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
984 status
= lttng_condition_buffer_usage_get_session_name(
985 condition
, &session_name
);
987 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
988 status
= lttng_condition_session_consumed_size_get_session_name(
989 condition
, &session_name
);
991 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
992 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
993 status
= lttng_condition_session_rotation_get_session_name(
994 condition
, &session_name
);
999 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
1000 ERR("Failed to retrieve session rotation condition's session name");
1004 return session_name
;
1008 bool evaluate_session_rotation_ongoing_condition(const struct lttng_condition
*condition
1009 __attribute__((unused
)),
1010 const struct session_state_sample
*sample
)
1012 return sample
->rotation
.ongoing
;
1016 bool evaluate_session_consumed_size_condition(
1017 const struct lttng_condition
*condition
,
1018 const struct session_state_sample
*sample
)
1021 const struct lttng_condition_session_consumed_size
*size_condition
=
1022 lttng::utils::container_of(condition
,
1023 <tng_condition_session_consumed_size::parent
);
1025 threshold
= size_condition
->consumed_threshold_bytes
.value
;
1026 DBG("Session consumed size condition being evaluated: threshold = %" PRIu64
", current size = %" PRIu64
,
1027 threshold
, sample
->consumed_data_size
);
1028 return sample
->consumed_data_size
>= threshold
;
1032 * `new_state` can be NULL to indicate that we are not evaluating a
1033 * state transition. A client subscribed or a trigger was registered and
1034 * we wish to perform an initial evaluation.
1037 int evaluate_session_condition(
1038 const struct lttng_condition
*condition
,
1039 const struct session_info
*session_info
,
1040 const struct session_state_sample
*new_state
,
1041 struct lttng_evaluation
**evaluation
)
1044 bool previous_result
, newest_result
;
1046 switch (lttng_condition_get_type(condition
)) {
1047 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1049 previous_result
= evaluate_session_rotation_ongoing_condition(
1050 condition
, &session_info
->last_state_sample
);
1051 newest_result
= evaluate_session_rotation_ongoing_condition(
1052 condition
, new_state
);
1054 previous_result
= false;
1055 newest_result
= evaluate_session_rotation_ongoing_condition(
1056 condition
, &session_info
->last_state_sample
);
1059 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
1061 previous_result
= evaluate_session_consumed_size_condition(
1062 condition
, &session_info
->last_state_sample
);
1063 newest_result
= evaluate_session_consumed_size_condition(
1064 condition
, new_state
);
1066 previous_result
= false;
1067 newest_result
= evaluate_session_consumed_size_condition(
1068 condition
, &session_info
->last_state_sample
);
1071 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1073 * Note that LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED is
1074 * evaluated differently to only consider state transitions without regard for the
1075 * initial state. This is a deliberate choice as it is unlikely that a user would
1076 * expect an action to occur for a rotation that occurred long before the trigger or
1077 * subscription occurred.
1084 previous_result
= !session_info
->last_state_sample
.rotation
.ongoing
;
1085 newest_result
= !new_state
->rotation
.ongoing
;
1092 if (!newest_result
|| (previous_result
== newest_result
)) {
1093 /* Not a state transition, evaluate to false. */
1098 switch (lttng_condition_get_type(condition
)) {
1099 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1101 const auto rotation_id
= new_state
?
1102 new_state
->rotation
.id
:
1103 session_info
->last_state_sample
.rotation
.id
;
1105 *evaluation
= lttng_evaluation_session_rotation_ongoing_create(rotation_id
);
1108 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1110 const auto rotation_id
= new_state
?
1111 new_state
->rotation
.id
:
1112 session_info
->last_state_sample
.rotation
.id
;
1114 /* Callee acquires a reference to location. */
1115 *evaluation
= lttng_evaluation_session_rotation_completed_create(
1116 rotation_id
, new_state
->rotation
.location
);
1119 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
1121 const auto latest_session_consumed_total
= new_state
?
1122 new_state
->consumed_data_size
:
1123 session_info
->last_state_sample
.consumed_data_size
;
1125 *evaluation
= lttng_evaluation_session_consumed_size_create(
1126 latest_session_consumed_total
);
1135 ERR("Failed to create session condition evaluation: session name = `%s`",
1136 session_info
->name
);
1147 int evaluate_condition_for_client(const struct lttng_trigger
*trigger
,
1148 const struct lttng_condition
*condition
,
1149 struct notification_client
*client
,
1150 struct notification_thread_state
*state
)
1153 struct lttng_evaluation
*evaluation
= NULL
;
1154 struct notification_client_list client_list
= {
1155 .lock
= PTHREAD_MUTEX_INITIALIZER
,
1158 .triggers_list
= {},
1160 .notification_trigger_clients_ht
= NULL
,
1161 .notification_trigger_clients_ht_node
= {},
1164 struct notification_client_list_element client_list_element
= {};
1165 uid_t object_uid
= 0;
1166 gid_t object_gid
= 0;
1168 LTTNG_ASSERT(trigger
);
1169 LTTNG_ASSERT(condition
);
1170 LTTNG_ASSERT(client
);
1171 LTTNG_ASSERT(state
);
1173 switch (get_condition_binding_object(condition
)) {
1174 case LTTNG_OBJECT_TYPE_SESSION
:
1176 /* Find the session associated with the condition. */
1177 const auto *session_name
= get_condition_session_name(condition
);
1178 auto session_info
= get_session_info_by_name(state
, session_name
);
1179 if (!session_info
) {
1180 /* Not an error, the session doesn't exist yet. */
1181 DBG("Session not found while evaluating session condition for client: session name = `%s`",
1187 object_uid
= session_info
->uid
;
1188 object_gid
= session_info
->gid
;
1190 ret
= evaluate_session_condition(condition
, session_info
, NULL
, &evaluation
);
1191 session_info_put(session_info
);
1194 case LTTNG_OBJECT_TYPE_CHANNEL
:
1195 ret
= evaluate_channel_condition_for_client(condition
, state
,
1196 &evaluation
, &object_uid
, &object_gid
);
1198 case LTTNG_OBJECT_TYPE_NONE
:
1199 DBG("Newly subscribed-to condition not bound to object, nothing to evaluate");
1202 case LTTNG_OBJECT_TYPE_UNKNOWN
:
1212 /* Evaluation yielded nothing. Normal exit. */
1213 DBG("Newly subscribed-to condition evaluated to false, nothing to report to client");
1219 * Create a temporary client list with the client currently
1222 cds_lfht_node_init(&client_list
.notification_trigger_clients_ht_node
);
1223 CDS_INIT_LIST_HEAD(&client_list
.clients_list
);
1225 CDS_INIT_LIST_HEAD(&client_list_element
.node
);
1226 client_list_element
.client
= client
;
1227 cds_list_add(&client_list_element
.node
, &client_list
.clients_list
);
1229 /* Send evaluation result to the newly-subscribed client. */
1230 DBG("Newly subscribed-to condition evaluated to true, notifying client");
1231 ret
= send_evaluation_to_clients(trigger
, evaluation
, &client_list
,
1232 state
, object_uid
, object_gid
);
1239 int notification_thread_client_subscribe(struct notification_client
*client
,
1240 struct lttng_condition
*condition
,
1241 struct notification_thread_state
*state
,
1242 enum lttng_notification_channel_status
*_status
)
1245 struct notification_client_list
*client_list
= NULL
;
1246 struct lttng_condition_list_element
*condition_list_element
= NULL
;
1247 struct notification_client_list_element
*client_list_element
= NULL
;
1248 struct lttng_trigger_ht_element
*trigger_ht_element
;
1249 enum lttng_notification_channel_status status
=
1250 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1253 * Ensure that the client has not already subscribed to this condition
1256 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
, node
) {
1257 if (lttng_condition_is_equal(condition_list_element
->condition
,
1259 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_ALREADY_SUBSCRIBED
;
1264 condition_list_element
= zmalloc
<lttng_condition_list_element
>();
1265 if (!condition_list_element
) {
1269 client_list_element
= zmalloc
<notification_client_list_element
>();
1270 if (!client_list_element
) {
1276 * Add the newly-subscribed condition to the client's subscription list.
1278 CDS_INIT_LIST_HEAD(&condition_list_element
->node
);
1279 condition_list_element
->condition
= condition
;
1281 cds_list_add(&condition_list_element
->node
, &client
->condition_list
);
1283 client_list
= get_client_list_from_condition(
1284 state
, condition_list_element
->condition
);
1287 * No notification-emiting trigger registered with this
1288 * condition. We don't evaluate the condition right away
1289 * since this trigger is not registered yet.
1291 free(client_list_element
);
1296 * The condition to which the client just subscribed is evaluated
1297 * at this point so that conditions that are already TRUE result
1298 * in a notification being sent out.
1300 * Note the iteration on all triggers which share an identical
1301 * `condition` than the one to which the client is registering. This is
1302 * done to ensure that the client receives a distinct notification for
1303 * all triggers that have a `notify` action that have this condition.
1305 pthread_mutex_lock(&client_list
->lock
);
1306 cds_list_for_each_entry(trigger_ht_element
,
1307 &client_list
->triggers_list
, client_list_trigger_node
) {
1308 if (evaluate_condition_for_client(trigger_ht_element
->trigger
, condition_list_element
->condition
,
1310 WARN("Evaluation of a condition on client subscription failed, aborting.");
1312 free(client_list_element
);
1313 pthread_mutex_unlock(&client_list
->lock
);
1317 pthread_mutex_unlock(&client_list
->lock
);
1320 * Add the client to the list of clients interested in a given trigger
1321 * if a "notification" trigger with a corresponding condition was
1324 client_list_element
->client
= client
;
1325 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
1327 pthread_mutex_lock(&client_list
->lock
);
1328 cds_list_add(&client_list_element
->node
, &client_list
->clients_list
);
1329 pthread_mutex_unlock(&client_list
->lock
);
1335 notification_client_list_put(client_list
);
1337 lttng_condition_destroy(condition
);
1340 free(condition_list_element
);
1341 free(client_list_element
);
1342 lttng_condition_destroy(condition
);
1347 int notification_thread_client_unsubscribe(
1348 struct notification_client
*client
,
1349 struct lttng_condition
*condition
,
1350 struct notification_thread_state
*state
,
1351 enum lttng_notification_channel_status
*_status
)
1353 struct notification_client_list
*client_list
;
1354 struct lttng_condition_list_element
*condition_list_element
,
1356 struct notification_client_list_element
*client_list_element
,
1358 bool condition_found
= false;
1359 enum lttng_notification_channel_status status
=
1360 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1362 /* Remove the condition from the client's condition list. */
1363 cds_list_for_each_entry_safe(condition_list_element
, condition_tmp
,
1364 &client
->condition_list
, node
) {
1365 if (!lttng_condition_is_equal(condition_list_element
->condition
,
1370 cds_list_del(&condition_list_element
->node
);
1372 * The caller may be iterating on the client's conditions to
1373 * tear down a client's connection. In this case, the condition
1374 * will be destroyed at the end.
1376 if (condition
!= condition_list_element
->condition
) {
1377 lttng_condition_destroy(
1378 condition_list_element
->condition
);
1380 free(condition_list_element
);
1381 condition_found
= true;
1385 if (!condition_found
) {
1386 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNKNOWN_CONDITION
;
1391 * Remove the client from the list of clients interested the trigger
1392 * matching the condition.
1394 client_list
= get_client_list_from_condition(state
, condition
);
1399 pthread_mutex_lock(&client_list
->lock
);
1400 cds_list_for_each_entry_safe(client_list_element
, client_tmp
,
1401 &client_list
->clients_list
, node
) {
1402 if (client_list_element
->client
->id
!= client
->id
) {
1405 cds_list_del(&client_list_element
->node
);
1406 free(client_list_element
);
1409 pthread_mutex_unlock(&client_list
->lock
);
1410 notification_client_list_put(client_list
);
1413 lttng_condition_destroy(condition
);
1421 void free_notification_client_rcu(struct rcu_head
*node
)
1423 free(lttng::utils::container_of(node
, ¬ification_client::rcu_node
));
1427 void notification_client_destroy(struct notification_client
*client
)
1434 * The client object is not reachable by other threads, no need to lock
1437 if (client
->socket
>= 0) {
1438 (void) lttcomm_close_unix_sock(client
->socket
);
1439 client
->socket
= -1;
1441 client
->communication
.active
= false;
1442 lttng_payload_reset(&client
->communication
.inbound
.payload
);
1443 lttng_payload_reset(&client
->communication
.outbound
.payload
);
1444 pthread_mutex_destroy(&client
->lock
);
1445 call_rcu(&client
->rcu_node
, free_notification_client_rcu
);
1449 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1453 struct notification_client
*get_client_from_socket(int socket
,
1454 struct notification_thread_state
*state
)
1456 struct cds_lfht_iter iter
;
1457 struct cds_lfht_node
*node
;
1458 struct notification_client
*client
= NULL
;
1460 ASSERT_RCU_READ_LOCKED();
1462 cds_lfht_lookup(state
->client_socket_ht
,
1463 hash_client_socket(socket
),
1464 match_client_socket
,
1465 (void *) (unsigned long) socket
,
1467 node
= cds_lfht_iter_get_node(&iter
);
1472 client
= caa_container_of(node
, struct notification_client
,
1473 client_socket_ht_node
);
1479 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1483 struct notification_client
*get_client_from_id(notification_client_id id
,
1484 struct notification_thread_state
*state
)
1486 struct cds_lfht_iter iter
;
1487 struct cds_lfht_node
*node
;
1488 struct notification_client
*client
= NULL
;
1490 ASSERT_RCU_READ_LOCKED();
1492 cds_lfht_lookup(state
->client_id_ht
,
1497 node
= cds_lfht_iter_get_node(&iter
);
1502 client
= caa_container_of(node
, struct notification_client
,
1509 bool buffer_usage_condition_applies_to_channel(
1510 const struct lttng_condition
*condition
,
1511 const struct channel_info
*channel_info
)
1513 enum lttng_condition_status status
;
1514 enum lttng_domain_type condition_domain
;
1515 const char *condition_session_name
= NULL
;
1516 const char *condition_channel_name
= NULL
;
1518 status
= lttng_condition_buffer_usage_get_domain_type(condition
,
1520 LTTNG_ASSERT(status
== LTTNG_CONDITION_STATUS_OK
);
1521 if (channel_info
->key
.domain
!= condition_domain
) {
1525 status
= lttng_condition_buffer_usage_get_session_name(
1526 condition
, &condition_session_name
);
1527 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1529 status
= lttng_condition_buffer_usage_get_channel_name(
1530 condition
, &condition_channel_name
);
1531 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_channel_name
);
1533 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1536 if (strcmp(channel_info
->name
, condition_channel_name
)) {
1546 bool trigger_applies_to_channel(const struct lttng_trigger
*trigger
,
1547 const struct channel_info
*channel_info
)
1549 const struct lttng_condition
*condition
;
1550 bool trigger_applies
;
1552 condition
= lttng_trigger_get_const_condition(trigger
);
1557 switch (lttng_condition_get_type(condition
)) {
1558 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
1559 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
1560 trigger_applies
= buffer_usage_condition_applies_to_channel(
1561 condition
, channel_info
);
1567 return trigger_applies
;
1572 /* Must be called with RCU read lock held. */
1574 struct lttng_session_trigger_list
*get_session_trigger_list(
1575 struct notification_thread_state
*state
,
1576 const char *session_name
)
1578 struct lttng_session_trigger_list
*list
= NULL
;
1579 struct cds_lfht_node
*node
;
1580 struct cds_lfht_iter iter
;
1582 ASSERT_RCU_READ_LOCKED();
1584 cds_lfht_lookup(state
->session_triggers_ht
,
1585 hash_key_str(session_name
, lttng_ht_seed
),
1586 match_session_trigger_list
,
1589 node
= cds_lfht_iter_get_node(&iter
);
1592 * Not an error, the list of triggers applying to that session
1593 * will be initialized when the session is created.
1595 DBG("No trigger list found for session \"%s\" as it is not yet known to the notification system",
1600 list
= caa_container_of(node
,
1601 struct lttng_session_trigger_list
,
1602 session_triggers_ht_node
);
1608 * Allocate an empty lttng_session_trigger_list for the session named
1612 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
1613 const char *session_name
,
1614 struct cds_lfht
*session_triggers_ht
)
1616 struct lttng_session_trigger_list
*list
= NULL
;
1617 char *session_name_copy
= strdup(session_name
);
1619 if (!session_name_copy
) {
1620 PERROR("Failed to allocate session name while building trigger list");
1624 list
= zmalloc
<lttng_session_trigger_list
>();
1626 PERROR("Failed to allocate session trigger list while building trigger list");
1630 list
->session_name
= session_name_copy
;
1631 CDS_INIT_LIST_HEAD(&list
->list
);
1632 cds_lfht_node_init(&list
->session_triggers_ht_node
);
1633 list
->session_triggers_ht
= session_triggers_ht
;
1636 /* Publish the list through the session_triggers_ht. */
1637 cds_lfht_add(session_triggers_ht
,
1638 hash_key_str(session_name
, lttng_ht_seed
),
1639 &list
->session_triggers_ht_node
);
1646 void free_session_trigger_list_rcu(struct rcu_head
*node
)
1648 struct lttng_session_trigger_list
*list
=
1649 caa_container_of(node
, struct lttng_session_trigger_list
, rcu_node
);
1651 free(list
->session_name
);
1656 void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list
*list
)
1658 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1660 /* Empty the list element by element, and then free the list itself. */
1661 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1662 &list
->list
, node
) {
1663 cds_list_del(&trigger_list_element
->node
);
1664 free(trigger_list_element
);
1667 /* Unpublish the list from the session_triggers_ht. */
1668 cds_lfht_del(list
->session_triggers_ht
,
1669 &list
->session_triggers_ht_node
);
1671 call_rcu(&list
->rcu_node
, free_session_trigger_list_rcu
);
1675 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
1676 struct lttng_trigger
*trigger
)
1679 struct lttng_trigger_list_element
*new_element
=
1680 zmalloc
<lttng_trigger_list_element
>();
1686 CDS_INIT_LIST_HEAD(&new_element
->node
);
1687 new_element
->trigger
= trigger
;
1688 cds_list_add(&new_element
->node
, &list
->list
);
1694 bool trigger_applies_to_session(const struct lttng_trigger
*trigger
,
1695 const char *session_name
)
1697 bool applies
= false;
1698 const struct lttng_condition
*condition
;
1700 condition
= lttng_trigger_get_const_condition(trigger
);
1701 switch (lttng_condition_get_type(condition
)) {
1702 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1703 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1704 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
1706 const char *condition_session_name
;
1708 condition_session_name
= get_condition_session_name(condition
);
1709 LTTNG_ASSERT(condition_session_name
);
1710 applies
= !strcmp(condition_session_name
, session_name
);
1721 * Allocate and initialize an lttng_session_trigger_list which contains
1722 * all triggers that apply to the session named 'session_name'.
1725 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
1726 const struct notification_thread_state
*state
,
1727 const char *session_name
)
1729 int trigger_count
= 0;
1730 struct lttng_session_trigger_list
*session_trigger_list
= NULL
;
1731 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1732 struct cds_lfht_iter iter
;
1734 session_trigger_list
= lttng_session_trigger_list_create(session_name
,
1735 state
->session_triggers_ht
);
1737 /* Add all triggers applying to the session named 'session_name'. */
1738 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1742 if (!trigger_applies_to_session(trigger_ht_element
->trigger
,
1747 ret
= lttng_session_trigger_list_add(session_trigger_list
,
1748 trigger_ht_element
->trigger
);
1756 DBG("Found %i triggers that apply to newly created session",
1758 return session_trigger_list
;
1760 lttng_session_trigger_list_destroy(session_trigger_list
);
1765 struct session_info
*create_and_publish_session_info(struct notification_thread_state
*state
,
1771 struct session_info
*session
= NULL
;
1772 struct lttng_session_trigger_list
*trigger_list
;
1775 trigger_list
= lttng_session_trigger_list_build(state
, name
);
1776 if (!trigger_list
) {
1780 session
= session_info_create(id
, name
, uid
, gid
, trigger_list
,
1781 state
->sessions_ht
);
1783 ERR("Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
1785 lttng_session_trigger_list_destroy(trigger_list
);
1789 /* Transferred ownership to the new session. */
1790 trigger_list
= NULL
;
1792 if (cds_lfht_add_unique(state
->sessions_ht
, hash_session_info(session
), match_session_info
,
1793 &id
, &session
->sessions_ht_node
) != &session
->sessions_ht_node
) {
1794 ERR("Duplicate session found: name = `%s`, id = %" PRIu64
, name
, id
);
1802 session_info_put(session
);
1807 int handle_notification_thread_command_add_channel(struct notification_thread_state
*state
,
1808 uint64_t session_id
,
1809 const char *channel_name
,
1810 enum lttng_domain_type channel_domain
,
1811 uint64_t channel_key_int
,
1812 uint64_t channel_capacity
,
1813 enum lttng_error_code
*cmd_result
)
1815 struct cds_list_head trigger_list
;
1816 struct channel_info
*new_channel_info
= NULL
;
1817 struct channel_key channel_key
= {
1818 .key
= channel_key_int
,
1819 .domain
= channel_domain
,
1821 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
1822 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1823 int trigger_count
= 0;
1824 struct cds_lfht_iter iter
;
1825 struct session_info
*session_info
= NULL
;
1827 DBG("Adding channel: channel name = `%s`, session id = %" PRIu64
", channel key = %" PRIu64
", domain = %s",
1828 channel_name
, session_id
, channel_key_int
,
1829 lttng_domain_type_str(channel_domain
));
1831 CDS_INIT_LIST_HEAD(&trigger_list
);
1833 session_info
= get_session_info_by_id(state
, session_id
);
1834 if (!session_info
) {
1835 /* Fatal logic error. */
1836 ERR("Failed to find session while adding channel: session id = %" PRIu64
,
1841 new_channel_info
= channel_info_create(channel_name
, &channel_key
,
1842 channel_capacity
, session_info
);
1843 if (!new_channel_info
) {
1848 /* Build a list of all triggers applying to the new channel. */
1849 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1851 struct lttng_trigger_list_element
*new_element
;
1853 if (!trigger_applies_to_channel(trigger_ht_element
->trigger
,
1854 new_channel_info
)) {
1858 new_element
= zmalloc
<lttng_trigger_list_element
>();
1863 CDS_INIT_LIST_HEAD(&new_element
->node
);
1864 new_element
->trigger
= trigger_ht_element
->trigger
;
1865 cds_list_add(&new_element
->node
, &trigger_list
);
1870 DBG("Found %i triggers that apply to newly added channel",
1872 channel_trigger_list
= zmalloc
<lttng_channel_trigger_list
>();
1873 if (!channel_trigger_list
) {
1876 channel_trigger_list
->channel_key
= new_channel_info
->key
;
1877 CDS_INIT_LIST_HEAD(&channel_trigger_list
->list
);
1878 cds_lfht_node_init(&channel_trigger_list
->channel_triggers_ht_node
);
1879 cds_list_splice(&trigger_list
, &channel_trigger_list
->list
);
1882 /* Add channel to the channel_ht which owns the channel_infos. */
1883 cds_lfht_add(state
->channels_ht
,
1884 hash_channel_key(&new_channel_info
->key
),
1885 &new_channel_info
->channels_ht_node
);
1887 * Add the list of triggers associated with this channel to the
1888 * channel_triggers_ht.
1890 cds_lfht_add(state
->channel_triggers_ht
,
1891 hash_channel_key(&new_channel_info
->key
),
1892 &channel_trigger_list
->channel_triggers_ht_node
);
1894 session_info_put(session_info
);
1895 *cmd_result
= LTTNG_OK
;
1898 channel_info_destroy(new_channel_info
);
1899 session_info_put(session_info
);
1904 int handle_notification_thread_command_add_session(struct notification_thread_state
*state
,
1905 uint64_t session_id
,
1906 const char *session_name
,
1909 enum lttng_error_code
*cmd_result
)
1913 DBG("Adding session: session name = `%s`, session id = %" PRIu64
", session uid = %d, session gid = %d",
1914 session_name
, session_id
, session_uid
, session_gid
);
1916 auto session
= create_and_publish_session_info(state
, session_id
, session_name
, session_uid
, session_gid
);
1918 PERROR("Failed to add session: session name = `%s`, session id = %" PRIu64
", session uid = %d, session gid = %d",
1919 session_name
, session_id
, session_uid
, session_gid
);
1921 *cmd_result
= LTTNG_ERR_NOMEM
;
1926 * Note that the reference to `session` is not released; this reference is
1927 * the "global" reference that is used to allow look-ups. This reference will
1928 * only be released when the session is removed. See
1929 * handle_notification_thread_command_remove_session.
1932 *cmd_result
= LTTNG_OK
;
1938 int handle_notification_thread_command_remove_session(
1939 struct notification_thread_state
*state
,
1940 uint64_t session_id
,
1941 enum lttng_error_code
*cmd_result
)
1945 DBG("Removing session: session id = %" PRIu64
, session_id
);
1947 auto session
= get_session_info_by_id(state
, session_id
);
1949 ERR("Failed to remove session: session id = %" PRIu64
, session_id
);
1951 *cmd_result
= LTTNG_ERR_NO_SESSION
;
1955 /* Release the reference returned by the look-up, and then release the global reference. */
1956 session_info_put(session
);
1957 session_info_put(session
);
1959 *cmd_result
= LTTNG_OK
;
1965 void free_channel_trigger_list_rcu(struct rcu_head
*node
)
1967 free(caa_container_of(node
, struct lttng_channel_trigger_list
,
1972 void free_channel_state_sample_rcu(struct rcu_head
*node
)
1974 free(caa_container_of(node
, struct channel_state_sample
,
1979 int handle_notification_thread_command_remove_channel(
1980 struct notification_thread_state
*state
,
1981 uint64_t channel_key
, enum lttng_domain_type domain
,
1982 enum lttng_error_code
*cmd_result
)
1984 struct cds_lfht_node
*node
;
1985 struct cds_lfht_iter iter
;
1986 struct lttng_channel_trigger_list
*trigger_list
;
1987 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1988 struct channel_key key
= { .key
= channel_key
, .domain
= domain
};
1989 struct channel_info
*channel_info
;
1991 DBG("Removing channel key = %" PRIu64
" in %s domain",
1992 channel_key
, lttng_domain_type_str(domain
));
1996 cds_lfht_lookup(state
->channel_triggers_ht
,
1997 hash_channel_key(&key
),
1998 match_channel_trigger_list
,
2001 node
= cds_lfht_iter_get_node(&iter
);
2003 * There is a severe internal error if we are being asked to remove a
2004 * channel that doesn't exist.
2007 ERR("Channel being removed is unknown to the notification thread");
2011 /* Free the list of triggers associated with this channel. */
2012 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
2013 channel_triggers_ht_node
);
2014 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
2015 &trigger_list
->list
, node
) {
2016 cds_list_del(&trigger_list_element
->node
);
2017 free(trigger_list_element
);
2019 cds_lfht_del(state
->channel_triggers_ht
, node
);
2020 call_rcu(&trigger_list
->rcu_node
, free_channel_trigger_list_rcu
);
2022 /* Free sampled channel state. */
2023 cds_lfht_lookup(state
->channel_state_ht
,
2024 hash_channel_key(&key
),
2025 match_channel_state_sample
,
2028 node
= cds_lfht_iter_get_node(&iter
);
2030 * This is expected to be NULL if the channel is destroyed before we
2031 * received a sample.
2034 struct channel_state_sample
*sample
= caa_container_of(node
,
2035 struct channel_state_sample
,
2036 channel_state_ht_node
);
2038 cds_lfht_del(state
->channel_state_ht
, node
);
2039 call_rcu(&sample
->rcu_node
, free_channel_state_sample_rcu
);
2042 /* Remove the channel from the channels_ht and free it. */
2043 cds_lfht_lookup(state
->channels_ht
,
2044 hash_channel_key(&key
),
2048 node
= cds_lfht_iter_get_node(&iter
);
2050 channel_info
= caa_container_of(node
, struct channel_info
,
2052 cds_lfht_del(state
->channels_ht
, node
);
2053 channel_info_destroy(channel_info
);
2056 *cmd_result
= LTTNG_OK
;
2061 int handle_notification_thread_command_session_rotation(
2062 struct notification_thread_state
*state
,
2063 enum notification_thread_command_type cmd_type
,
2064 uint64_t session_id
,
2065 uint64_t trace_archive_chunk_id
,
2066 struct lttng_trace_archive_location
*location
,
2067 enum lttng_error_code
*_cmd_result
)
2070 enum lttng_error_code cmd_result
= LTTNG_OK
;
2071 struct lttng_session_trigger_list
*trigger_list
;
2072 struct lttng_trigger_list_element
*trigger_list_element
;
2073 struct session_info
*session_info
;
2074 struct lttng_credentials session_creds
;
2075 struct session_state_sample new_session_state
;
2079 session_info
= get_session_info_by_id(state
, session_id
);
2080 if (!session_info
) {
2081 /* Fatal logic error. */
2082 ERR("Failed to find session while handling rotation state change: session id = %" PRIu64
,
2085 cmd_result
= LTTNG_ERR_FATAL
;
2089 new_session_state
= session_info
->last_state_sample
;
2091 lttng_trace_archive_location_get(location
);
2092 new_session_state
.rotation
.location
= location
;
2094 new_session_state
.rotation
.location
= NULL
;
2098 .uid
= LTTNG_OPTIONAL_INIT_VALUE(session_info
->uid
),
2099 .gid
= LTTNG_OPTIONAL_INIT_VALUE(session_info
->gid
),
2102 new_session_state
.rotation
.ongoing
= cmd_type
==
2103 NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
;
2104 new_session_state
.rotation
.id
= trace_archive_chunk_id
;
2106 trigger_list
= get_session_trigger_list(state
, session_info
->name
);
2107 LTTNG_ASSERT(trigger_list
);
2109 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
2111 const struct lttng_condition
*condition
;
2112 struct lttng_trigger
*trigger
;
2113 struct notification_client_list
*client_list
;
2114 struct lttng_evaluation
*evaluation
= NULL
;
2115 enum action_executor_status executor_status
;
2117 trigger
= trigger_list_element
->trigger
;
2118 condition
= lttng_trigger_get_const_condition(trigger
);
2119 LTTNG_ASSERT(condition
);
2121 ret
= evaluate_session_condition(
2122 condition
, session_info
, &new_session_state
, &evaluation
);
2125 cmd_result
= LTTNG_ERR_NOMEM
;
2134 * Ownership of `evaluation` transferred to the action executor
2135 * no matter the result. The callee acquires a reference to the
2136 * client list: we can release our own.
2138 client_list
= get_client_list_from_condition(state
, condition
);
2139 executor_status
= action_executor_enqueue_trigger(
2140 state
->executor
, trigger
, evaluation
,
2141 &session_creds
, client_list
);
2142 notification_client_list_put(client_list
);
2144 switch (executor_status
) {
2145 case ACTION_EXECUTOR_STATUS_OK
:
2147 case ACTION_EXECUTOR_STATUS_ERROR
:
2148 case ACTION_EXECUTOR_STATUS_INVALID
:
2150 * TODO Add trigger identification (name/id) when
2151 * it is added to the API.
2153 ERR("Fatal error occurred while enqueuing action associated with session rotation trigger");
2156 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
2158 * TODO Add trigger identification (name/id) when
2159 * it is added to the API.
2161 * Not a fatal error.
2163 WARN("No space left when enqueuing action associated with session rotation trigger");
2173 /* Ownership of new_session_state::location is transferred. */
2174 lttng_trace_archive_location_put(session_info
->last_state_sample
.rotation
.location
);
2175 session_info
->last_state_sample
= new_session_state
;
2178 session_info_put(session_info
);
2179 *_cmd_result
= cmd_result
;
2185 int handle_notification_thread_command_add_tracer_event_source(
2186 struct notification_thread_state
*state
,
2187 int tracer_event_source_fd
,
2188 enum lttng_domain_type domain_type
,
2189 enum lttng_error_code
*_cmd_result
)
2192 enum lttng_error_code cmd_result
= LTTNG_OK
;
2193 struct notification_event_tracer_event_source_element
*element
= NULL
;
2195 element
= zmalloc
<notification_event_tracer_event_source_element
>();
2197 cmd_result
= LTTNG_ERR_NOMEM
;
2202 element
->fd
= tracer_event_source_fd
;
2203 element
->domain
= domain_type
;
2205 cds_list_add(&element
->node
, &state
->tracer_event_sources_list
);
2207 DBG3("Adding tracer event source fd to poll set: tracer_event_source_fd = %d, domain = '%s'",
2208 tracer_event_source_fd
,
2209 lttng_domain_type_str(domain_type
));
2211 /* Adding the read side pipe to the event poll. */
2212 ret
= lttng_poll_add(&state
->events
, tracer_event_source_fd
, LPOLLPRI
| LPOLLIN
| LPOLLERR
);
2214 ERR("Failed to add tracer event source to poll set: tracer_event_source_fd = %d, domain = '%s'",
2215 tracer_event_source_fd
,
2216 lttng_domain_type_str(element
->domain
));
2217 cds_list_del(&element
->node
);
2222 element
->is_fd_in_poll_set
= true;
2225 *_cmd_result
= cmd_result
;
2230 int drain_event_notifier_notification_pipe(
2231 struct notification_thread_state
*state
,
2232 int pipe
, enum lttng_domain_type domain
)
2234 struct lttng_poll_event events
= {};
2237 ret
= lttng_poll_create(&events
, 1, LTTNG_CLOEXEC
);
2239 ERR("Error creating lttng_poll_event");
2243 ret
= lttng_poll_add(&events
, pipe
, LPOLLIN
);
2245 ERR("Error adding fd event notifier notification pipe to lttng_poll_event: fd = %d",
2252 * Continue to consume notifications as long as there are new
2253 * ones coming in. The tracer has been asked to stop producing
2256 * LPOLLIN is explicitly checked since LPOLLHUP is implicitly
2257 * monitored (on Linux, at least) and will be returned when
2258 * the pipe is closed but empty.
2260 ret
= lttng_poll_wait_interruptible(&events
, 0);
2261 if (ret
== 0 || (LTTNG_POLL_GETEV(&events
, 0) & LPOLLIN
) == 0) {
2262 /* No more notification to be read on this pipe. */
2265 } else if (ret
< 0) {
2266 PERROR("Failed on lttng_poll_wait_interruptible() call");
2271 ret
= handle_one_event_notifier_notification(state
, pipe
, domain
);
2273 ERR("Error consuming an event notifier notification from pipe: fd = %d",
2278 lttng_poll_clean(&events
);
2283 struct notification_event_tracer_event_source_element
*
2284 find_tracer_event_source_element(struct notification_thread_state
*state
,
2285 int tracer_event_source_fd
)
2287 struct notification_event_tracer_event_source_element
*source_element
;
2289 cds_list_for_each_entry(source_element
,
2290 &state
->tracer_event_sources_list
, node
) {
2291 if (source_element
->fd
== tracer_event_source_fd
) {
2296 source_element
= NULL
;
2298 return source_element
;
2302 int remove_tracer_event_source_from_pollset(
2303 struct notification_thread_state
*state
,
2304 struct notification_event_tracer_event_source_element
*source_element
)
2308 LTTNG_ASSERT(source_element
->is_fd_in_poll_set
);
2310 DBG3("Removing tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2312 lttng_domain_type_str(source_element
->domain
));
2314 /* Removing the fd from the event poll set. */
2315 ret
= lttng_poll_del(&state
->events
, source_element
->fd
);
2317 ERR("Failed to remove tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2319 lttng_domain_type_str(source_element
->domain
));
2324 source_element
->is_fd_in_poll_set
= false;
2327 * Force the notification thread to restart the poll() loop to ensure
2328 * that any events from the removed fd are removed.
2330 state
->restart_poll
= true;
2332 ret
= drain_event_notifier_notification_pipe(state
, source_element
->fd
,
2333 source_element
->domain
);
2335 ERR("Error draining event notifier notification: tracer_event_source_fd = %d, domain = %s",
2337 lttng_domain_type_str(source_element
->domain
));
2346 int handle_notification_thread_tracer_event_source_died(
2347 struct notification_thread_state
*state
,
2348 int tracer_event_source_fd
)
2351 struct notification_event_tracer_event_source_element
*source_element
;
2353 source_element
= find_tracer_event_source_element(state
,
2354 tracer_event_source_fd
);
2356 LTTNG_ASSERT(source_element
);
2358 ret
= remove_tracer_event_source_from_pollset(state
, source_element
);
2360 ERR("Failed to remove dead tracer event source from poll set");
2367 int handle_notification_thread_command_remove_tracer_event_source(
2368 struct notification_thread_state
*state
,
2369 int tracer_event_source_fd
,
2370 enum lttng_error_code
*_cmd_result
)
2373 enum lttng_error_code cmd_result
= LTTNG_OK
;
2374 struct notification_event_tracer_event_source_element
*source_element
= NULL
;
2376 source_element
= find_tracer_event_source_element(state
,
2377 tracer_event_source_fd
);
2379 LTTNG_ASSERT(source_element
);
2381 /* Remove the tracer source from the list. */
2382 cds_list_del(&source_element
->node
);
2384 if (!source_element
->is_fd_in_poll_set
) {
2385 /* Skip the poll set removal. */
2389 ret
= remove_tracer_event_source_from_pollset(state
, source_element
);
2391 ERR("Failed to remove tracer event source from poll set");
2392 cmd_result
= LTTNG_ERR_FATAL
;
2396 free(source_element
);
2397 *_cmd_result
= cmd_result
;
2401 static int handle_notification_thread_command_list_triggers(
2402 struct notification_thread_handle
*handle
__attribute__((unused
)),
2403 struct notification_thread_state
*state
,
2405 struct lttng_triggers
**triggers
,
2406 enum lttng_error_code
*_cmd_result
)
2409 enum lttng_error_code cmd_result
= LTTNG_OK
;
2410 struct cds_lfht_iter iter
;
2411 struct lttng_trigger_ht_element
*trigger_ht_element
;
2412 struct lttng_triggers
*local_triggers
= NULL
;
2413 const struct lttng_credentials
*creds
;
2417 local_triggers
= lttng_triggers_create();
2418 if (!local_triggers
) {
2419 /* Not a fatal error. */
2420 cmd_result
= LTTNG_ERR_NOMEM
;
2424 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
,
2425 trigger_ht_element
, node
) {
2427 * Only return the triggers to which the client has access.
2428 * The root user has visibility over all triggers.
2430 creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
2431 if (client_uid
!= lttng_credentials_get_uid(creds
) && client_uid
!= 0) {
2435 ret
= lttng_triggers_add(local_triggers
,
2436 trigger_ht_element
->trigger
);
2438 /* Not a fatal error. */
2440 cmd_result
= LTTNG_ERR_NOMEM
;
2445 /* Transferring ownership to the caller. */
2446 *triggers
= local_triggers
;
2447 local_triggers
= NULL
;
2451 lttng_triggers_destroy(local_triggers
);
2452 *_cmd_result
= cmd_result
;
2456 static inline void get_trigger_info_for_log(const struct lttng_trigger
*trigger
,
2457 const char **trigger_name
,
2458 uid_t
*trigger_owner_uid
)
2460 enum lttng_trigger_status trigger_status
;
2462 trigger_status
= lttng_trigger_get_name(trigger
, trigger_name
);
2463 switch (trigger_status
) {
2464 case LTTNG_TRIGGER_STATUS_OK
:
2466 case LTTNG_TRIGGER_STATUS_UNSET
:
2467 *trigger_name
= "(anonymous)";
2473 trigger_status
= lttng_trigger_get_owner_uid(trigger
,
2475 LTTNG_ASSERT(trigger_status
== LTTNG_TRIGGER_STATUS_OK
);
2478 static int handle_notification_thread_command_get_trigger(
2479 struct notification_thread_state
*state
,
2480 const struct lttng_trigger
*trigger
,
2481 struct lttng_trigger
**registered_trigger
,
2482 enum lttng_error_code
*_cmd_result
)
2485 struct cds_lfht_iter iter
;
2486 struct lttng_trigger_ht_element
*trigger_ht_element
;
2487 enum lttng_error_code cmd_result
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
2488 const char *trigger_name
;
2489 uid_t trigger_owner_uid
;
2493 cds_lfht_for_each_entry(
2494 state
->triggers_ht
, &iter
, trigger_ht_element
, node
) {
2495 if (lttng_trigger_is_equal(
2496 trigger
, trigger_ht_element
->trigger
)) {
2497 /* Take one reference on the return trigger. */
2498 *registered_trigger
= trigger_ht_element
->trigger
;
2499 lttng_trigger_get(*registered_trigger
);
2501 cmd_result
= LTTNG_OK
;
2506 /* Not a fatal error if the trigger is not found. */
2507 get_trigger_info_for_log(trigger
, &trigger_name
, &trigger_owner_uid
);
2508 DBG("Failed to retrieve registered version of trigger: trigger name = '%s', trigger owner uid = %d",
2509 trigger_name
, (int) trigger_owner_uid
);
2515 *_cmd_result
= cmd_result
;
2520 bool condition_is_supported(struct lttng_condition
*condition
)
2524 switch (lttng_condition_get_type(condition
)) {
2525 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
2526 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
2529 enum lttng_domain_type domain
;
2531 ret
= lttng_condition_buffer_usage_get_domain_type(condition
,
2533 LTTNG_ASSERT(ret
== 0);
2535 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2536 is_supported
= true;
2541 * Older kernel tracers don't expose the API to monitor their
2542 * buffers. Therefore, we reject triggers that require that
2543 * mechanism to be available to be evaluated.
2545 * Assume unsupported on error.
2547 is_supported
= kernel_supports_ring_buffer_snapshot_sample_positions() == 1;
2550 case LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES
:
2552 const struct lttng_event_rule
*event_rule
;
2553 enum lttng_domain_type domain
;
2554 const enum lttng_condition_status status
=
2555 lttng_condition_event_rule_matches_get_rule(
2556 condition
, &event_rule
);
2558 LTTNG_ASSERT(status
== LTTNG_CONDITION_STATUS_OK
);
2560 domain
= lttng_event_rule_get_domain_type(event_rule
);
2561 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2562 is_supported
= true;
2567 * Older kernel tracers can't emit notification. Therefore, we
2568 * reject triggers that require that mechanism to be available
2571 * Assume unsupported on error.
2573 is_supported
= kernel_supports_event_notifiers() == 1;
2577 is_supported
= true;
2580 return is_supported
;
2583 /* Must be called with RCU read lock held. */
2585 int bind_trigger_to_matching_session(struct lttng_trigger
*trigger
,
2586 struct notification_thread_state
*state
)
2589 const struct lttng_condition
*condition
;
2590 const char *session_name
;
2591 struct lttng_session_trigger_list
*trigger_list
;
2593 ASSERT_RCU_READ_LOCKED();
2595 condition
= lttng_trigger_get_const_condition(trigger
);
2596 session_name
= get_condition_session_name(condition
);
2598 trigger_list
= get_session_trigger_list(state
, session_name
);
2599 if (!trigger_list
) {
2600 DBG("Unable to bind trigger applying to session \"%s\" as it is not yet known to the notification system",
2606 DBG("Newly registered trigger bound to session \"%s\"",
2608 ret
= lttng_session_trigger_list_add(trigger_list
, trigger
);
2613 /* Must be called with RCU read lock held. */
2615 int bind_trigger_to_matching_channels(struct lttng_trigger
*trigger
,
2616 struct notification_thread_state
*state
)
2619 struct cds_lfht_node
*node
;
2620 struct cds_lfht_iter iter
;
2621 struct channel_info
*channel
;
2623 ASSERT_RCU_READ_LOCKED();
2625 cds_lfht_for_each_entry(state
->channels_ht
, &iter
, channel
,
2627 struct lttng_trigger_list_element
*trigger_list_element
;
2628 struct lttng_channel_trigger_list
*trigger_list
;
2629 struct cds_lfht_iter lookup_iter
;
2631 if (!trigger_applies_to_channel(trigger
, channel
)) {
2635 cds_lfht_lookup(state
->channel_triggers_ht
,
2636 hash_channel_key(&channel
->key
),
2637 match_channel_trigger_list
,
2640 node
= cds_lfht_iter_get_node(&lookup_iter
);
2642 trigger_list
= caa_container_of(node
,
2643 struct lttng_channel_trigger_list
,
2644 channel_triggers_ht_node
);
2646 trigger_list_element
= zmalloc
<lttng_trigger_list_element
>();
2647 if (!trigger_list_element
) {
2651 CDS_INIT_LIST_HEAD(&trigger_list_element
->node
);
2652 trigger_list_element
->trigger
= trigger
;
2653 cds_list_add(&trigger_list_element
->node
, &trigger_list
->list
);
2654 DBG("Newly registered trigger bound to channel \"%s\"",
2662 bool is_trigger_action_notify(const struct lttng_trigger
*trigger
)
2664 bool is_notify
= false;
2665 unsigned int i
, count
;
2666 enum lttng_action_status action_status
;
2667 const struct lttng_action
*action
=
2668 lttng_trigger_get_const_action(trigger
);
2669 enum lttng_action_type action_type
;
2671 LTTNG_ASSERT(action
);
2672 action_type
= lttng_action_get_type(action
);
2673 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2676 } else if (action_type
!= LTTNG_ACTION_TYPE_LIST
) {
2680 action_status
= lttng_action_list_get_count(action
, &count
);
2681 LTTNG_ASSERT(action_status
== LTTNG_ACTION_STATUS_OK
);
2683 for (i
= 0; i
< count
; i
++) {
2684 const struct lttng_action
*inner_action
=
2685 lttng_action_list_get_at_index(
2688 action_type
= lttng_action_get_type(inner_action
);
2689 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2699 static bool trigger_name_taken(struct notification_thread_state
*state
,
2700 const struct lttng_trigger
*trigger
)
2702 struct cds_lfht_iter iter
;
2705 * No duplicata is allowed in the triggers_by_name_uid_ht.
2706 * The match is done against the trigger name and uid.
2708 cds_lfht_lookup(state
->triggers_by_name_uid_ht
,
2709 hash_trigger_by_name_uid(trigger
),
2710 match_trigger_by_name_uid
,
2713 return !!cds_lfht_iter_get_node(&iter
);
2717 enum lttng_error_code
generate_trigger_name(
2718 struct notification_thread_state
*state
,
2719 struct lttng_trigger
*trigger
, const char **name
)
2721 enum lttng_error_code ret_code
= LTTNG_OK
;
2723 enum lttng_trigger_status status
;
2726 const int ret
= lttng_trigger_generate_name(trigger
,
2727 state
->trigger_id
.name_offset
++);
2729 /* The only reason this can fail right now. */
2730 ret_code
= LTTNG_ERR_NOMEM
;
2734 status
= lttng_trigger_get_name(trigger
, name
);
2735 LTTNG_ASSERT(status
== LTTNG_TRIGGER_STATUS_OK
);
2737 taken
= trigger_name_taken(state
, trigger
);
2738 } while (taken
|| state
->trigger_id
.name_offset
== UINT64_MAX
);
2744 void notif_thread_state_remove_trigger_ht_elem(
2745 struct notification_thread_state
*state
,
2746 struct lttng_trigger_ht_element
*trigger_ht_element
)
2748 LTTNG_ASSERT(state
);
2749 LTTNG_ASSERT(trigger_ht_element
);
2751 cds_lfht_del(state
->triggers_ht
, &trigger_ht_element
->node
);
2752 cds_lfht_del(state
->triggers_by_name_uid_ht
, &trigger_ht_element
->node_by_name_uid
);
2756 enum lttng_error_code
setup_tracer_notifier(
2757 struct notification_thread_state
*state
,
2758 struct lttng_trigger
*trigger
)
2760 enum lttng_error_code ret
;
2761 enum event_notifier_error_accounting_status error_accounting_status
;
2762 struct cds_lfht_node
*node
;
2763 uint64_t error_counter_index
= 0;
2764 struct lttng_condition
*condition
= lttng_trigger_get_condition(trigger
);
2765 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
= NULL
;
2767 trigger_tokens_ht_element
= zmalloc
<notification_trigger_tokens_ht_element
>();
2768 if (!trigger_tokens_ht_element
) {
2769 ret
= LTTNG_ERR_NOMEM
;
2773 /* Add trigger token to the trigger_tokens_ht. */
2774 cds_lfht_node_init(&trigger_tokens_ht_element
->node
);
2775 trigger_tokens_ht_element
->token
= LTTNG_OPTIONAL_GET(trigger
->tracer_token
);
2776 trigger_tokens_ht_element
->trigger
= trigger
;
2778 node
= cds_lfht_add_unique(state
->trigger_tokens_ht
,
2779 hash_key_u64(&trigger_tokens_ht_element
->token
, lttng_ht_seed
),
2780 match_trigger_token
,
2781 &trigger_tokens_ht_element
->token
,
2782 &trigger_tokens_ht_element
->node
);
2783 if (node
!= &trigger_tokens_ht_element
->node
) {
2784 ret
= LTTNG_ERR_TRIGGER_EXISTS
;
2785 goto error_free_ht_element
;
2788 error_accounting_status
= event_notifier_error_accounting_register_event_notifier(
2789 trigger
, &error_counter_index
);
2790 if (error_accounting_status
!= EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK
) {
2791 if (error_accounting_status
== EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_NO_INDEX_AVAILABLE
) {
2792 DBG("Trigger list error accounting counter full.");
2793 ret
= LTTNG_ERR_EVENT_NOTIFIER_ERROR_ACCOUNTING_FULL
;
2795 ERR("Error registering trigger for error accounting");
2796 ret
= LTTNG_ERR_EVENT_NOTIFIER_REGISTRATION
;
2799 goto error_remove_ht_element
;
2802 lttng_condition_event_rule_matches_set_error_counter_index(
2803 condition
, error_counter_index
);
2808 error_remove_ht_element
:
2809 cds_lfht_del(state
->trigger_tokens_ht
, &trigger_tokens_ht_element
->node
);
2810 error_free_ht_element
:
2811 free(trigger_tokens_ht_element
);
2817 * FIXME A client's credentials are not checked when registering a trigger.
2819 * The effects of this are benign since:
2820 * - The client will succeed in registering the trigger, as it is valid,
2821 * - The trigger will, internally, be bound to the channel/session,
2822 * - The notifications will not be sent since the client's credentials
2823 * are checked against the channel at that moment.
2825 * If this function returns a non-zero value, it means something is
2826 * fundamentally broken and the whole subsystem/thread will be torn down.
2828 * If a non-fatal error occurs, just set the cmd_result to the appropriate
2832 int handle_notification_thread_command_register_trigger(
2833 struct notification_thread_state
*state
,
2834 struct lttng_trigger
*trigger
,
2835 bool is_trigger_anonymous
,
2836 enum lttng_error_code
*cmd_result
)
2839 struct lttng_condition
*condition
;
2840 struct notification_client_list
*client_list
= NULL
;
2841 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2842 struct cds_lfht_node
*node
;
2843 const char* trigger_name
;
2844 bool free_trigger
= true;
2845 struct lttng_evaluation
*evaluation
= NULL
;
2846 struct lttng_credentials object_creds
;
2849 enum action_executor_status executor_status
;
2850 const uint64_t trigger_tracer_token
=
2851 state
->trigger_id
.next_tracer_token
++;
2855 /* Set the trigger's tracer token. */
2856 lttng_trigger_set_tracer_token(trigger
, trigger_tracer_token
);
2858 if (!is_trigger_anonymous
) {
2859 if (lttng_trigger_get_name(trigger
, &trigger_name
) ==
2860 LTTNG_TRIGGER_STATUS_UNSET
) {
2861 const enum lttng_error_code ret_code
=
2862 generate_trigger_name(state
, trigger
,
2865 if (ret_code
!= LTTNG_OK
) {
2868 *cmd_result
= ret_code
;
2871 } else if (trigger_name_taken(state
, trigger
)) {
2872 /* Not a fatal error. */
2873 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2878 trigger_name
= "(anonymous)";
2881 condition
= lttng_trigger_get_condition(trigger
);
2882 LTTNG_ASSERT(condition
);
2884 /* Some conditions require tracers to implement a minimal ABI version. */
2885 if (!condition_is_supported(condition
)) {
2886 *cmd_result
= LTTNG_ERR_NOT_SUPPORTED
;
2890 trigger_ht_element
= zmalloc
<lttng_trigger_ht_element
>();
2891 if (!trigger_ht_element
) {
2896 /* Add trigger to the trigger_ht. */
2897 cds_lfht_node_init(&trigger_ht_element
->node
);
2898 cds_lfht_node_init(&trigger_ht_element
->node_by_name_uid
);
2899 trigger_ht_element
->trigger
= trigger
;
2901 node
= cds_lfht_add_unique(state
->triggers_ht
,
2902 lttng_condition_hash(condition
),
2905 &trigger_ht_element
->node
);
2906 if (node
!= &trigger_ht_element
->node
) {
2907 /* Not a fatal error, simply report it to the client. */
2908 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2909 goto error_free_ht_element
;
2912 node
= cds_lfht_add_unique(state
->triggers_by_name_uid_ht
,
2913 hash_trigger_by_name_uid(trigger
),
2914 match_trigger_by_name_uid
,
2916 &trigger_ht_element
->node_by_name_uid
);
2917 if (node
!= &trigger_ht_element
->node_by_name_uid
) {
2918 /* Internal error: add to triggers_ht should have failed. */
2920 goto error_free_ht_element
;
2923 /* From this point consider the trigger registered. */
2924 lttng_trigger_set_as_registered(trigger
);
2927 * Some triggers might need a tracer notifier depending on its
2928 * condition and actions.
2930 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
2931 enum lttng_error_code error_code
;
2933 error_code
= setup_tracer_notifier(state
, trigger
);
2934 if (error_code
!= LTTNG_OK
) {
2935 notif_thread_state_remove_trigger_ht_elem(state
,
2936 trigger_ht_element
);
2937 if (error_code
== LTTNG_ERR_NOMEM
) {
2940 *cmd_result
= error_code
;
2944 goto error_free_ht_element
;
2949 * The rest only applies to triggers that have a "notify" action.
2950 * It is not skipped as this is the only action type currently
2953 if (is_trigger_action_notify(trigger
)) {
2955 * Find or create the client list of this condition. It may
2956 * already be present if another trigger is already registered
2957 * with the same condition.
2959 client_list
= get_client_list_from_condition(state
, condition
);
2962 * No client list for this condition yet. We create new
2963 * one and build it up.
2965 client_list
= notification_client_list_create(state
, condition
);
2967 ERR("Error creating notification client list for trigger %s", trigger
->name
);
2968 goto error_free_ht_element
;
2972 CDS_INIT_LIST_HEAD(&trigger_ht_element
->client_list_trigger_node
);
2974 pthread_mutex_lock(&client_list
->lock
);
2975 cds_list_add(&trigger_ht_element
->client_list_trigger_node
, &client_list
->triggers_list
);
2976 pthread_mutex_unlock(&client_list
->lock
);
2980 * Ownership of the trigger and of its wrapper was transfered to
2981 * the triggers_ht. Same for token ht element if necessary.
2983 trigger_ht_element
= NULL
;
2984 free_trigger
= false;
2986 switch (get_condition_binding_object(condition
)) {
2987 case LTTNG_OBJECT_TYPE_SESSION
:
2988 /* Add the trigger to the list if it matches a known session. */
2989 ret
= bind_trigger_to_matching_session(trigger
, state
);
2991 goto error_free_ht_element
;
2994 case LTTNG_OBJECT_TYPE_CHANNEL
:
2996 * Add the trigger to list of triggers bound to the channels
2999 ret
= bind_trigger_to_matching_channels(trigger
, state
);
3001 goto error_free_ht_element
;
3004 case LTTNG_OBJECT_TYPE_NONE
:
3007 ERR("Unknown object type on which to bind a newly registered trigger was encountered");
3009 goto error_free_ht_element
;
3013 * The new trigger's condition must be evaluated against the current
3016 * In the case of `notify` action, nothing preventing clients from
3017 * subscribing to a condition before the corresponding trigger is
3018 * registered, we have to evaluate this new condition right away.
3020 * At some point, we were waiting for the next "evaluation" (e.g. on
3021 * reception of a channel sample) to evaluate this new condition, but
3024 * The reason it was broken is that waiting for the next sample
3025 * does not allow us to properly handle transitions for edge-triggered
3028 * Consider this example: when we handle a new channel sample, we
3029 * evaluate each conditions twice: once with the previous state, and
3030 * again with the newest state. We then use those two results to
3031 * determine whether a state change happened: a condition was false and
3032 * became true. If a state change happened, we have to notify clients.
3034 * Now, if a client subscribes to a given notification and registers
3035 * a trigger *after* that subscription, we have to make sure the
3036 * condition is evaluated at this point while considering only the
3037 * current state. Otherwise, the next evaluation cycle may only see
3038 * that the evaluations remain the same (true for samples n-1 and n) and
3039 * the client will never know that the condition has been met.
3041 switch (get_condition_binding_object(condition
)) {
3042 case LTTNG_OBJECT_TYPE_SESSION
:
3044 /* Find the session associated with the condition. */
3045 const auto *session_name
= get_condition_session_name(condition
);
3046 auto session_info
= get_session_info_by_name(state
, session_name
);
3047 if (!session_info
) {
3048 /* Not an error, the session doesn't exist yet. */
3049 DBG("Session not found while evaluating session condition during registration of trigger: session name = `%s`",
3055 LTTNG_OPTIONAL_SET(&object_creds
.uid
, session_info
->uid
);
3056 LTTNG_OPTIONAL_SET(&object_creds
.gid
, session_info
->gid
);
3058 ret
= evaluate_session_condition(condition
, session_info
, NULL
, &evaluation
);
3059 session_info_put(session_info
);
3062 case LTTNG_OBJECT_TYPE_CHANNEL
:
3063 ret
= evaluate_channel_condition_for_client(condition
, state
,
3064 &evaluation
, &object_uid
,
3066 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
3067 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
3069 case LTTNG_OBJECT_TYPE_NONE
:
3072 case LTTNG_OBJECT_TYPE_UNKNOWN
:
3080 goto error_free_ht_element
;
3083 DBG("Newly registered trigger's condition evaluated to %s",
3084 evaluation
? "true" : "false");
3086 /* Evaluation yielded nothing. Normal exit. */
3092 * Ownership of `evaluation` transferred to the action executor
3093 * no matter the result.
3095 executor_status
= action_executor_enqueue_trigger(state
->executor
,
3096 trigger
, evaluation
, &object_creds
, client_list
);
3098 switch (executor_status
) {
3099 case ACTION_EXECUTOR_STATUS_OK
:
3101 case ACTION_EXECUTOR_STATUS_ERROR
:
3102 case ACTION_EXECUTOR_STATUS_INVALID
:
3104 * TODO Add trigger identification (name/id) when
3105 * it is added to the API.
3107 ERR("Fatal error occurred while enqueuing action associated to newly registered trigger");
3109 goto error_free_ht_element
;
3110 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
3112 * TODO Add trigger identification (name/id) when
3113 * it is added to the API.
3115 * Not a fatal error.
3117 WARN("No space left when enqueuing action associated to newly registered trigger");
3125 *cmd_result
= LTTNG_OK
;
3126 DBG("Registered trigger: name = `%s`, tracer token = %" PRIu64
,
3127 trigger_name
, trigger_tracer_token
);
3130 error_free_ht_element
:
3131 if (trigger_ht_element
) {
3132 /* Delayed removal due to RCU constraint on delete. */
3133 call_rcu(&trigger_ht_element
->rcu_node
,
3134 free_lttng_trigger_ht_element_rcu
);
3139 * Other objects might have a reference to the trigger, mark it
3142 lttng_trigger_set_as_unregistered(trigger
);
3143 lttng_trigger_destroy(trigger
);
3151 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
)
3153 free(caa_container_of(node
, struct lttng_trigger_ht_element
,
3158 void free_notification_trigger_tokens_ht_element_rcu(struct rcu_head
*node
)
3160 free(caa_container_of(node
, struct notification_trigger_tokens_ht_element
,
3165 void teardown_tracer_notifier(struct notification_thread_state
*state
,
3166 const struct lttng_trigger
*trigger
)
3168 struct cds_lfht_iter iter
;
3169 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
;
3171 cds_lfht_for_each_entry(state
->trigger_tokens_ht
, &iter
,
3172 trigger_tokens_ht_element
, node
) {
3174 if (!lttng_trigger_is_equal(trigger
,
3175 trigger_tokens_ht_element
->trigger
)) {
3179 event_notifier_error_accounting_unregister_event_notifier(
3180 trigger_tokens_ht_element
->trigger
);
3182 /* TODO talk to all app and remove it */
3183 DBG("Removed trigger from tokens_ht");
3184 cds_lfht_del(state
->trigger_tokens_ht
,
3185 &trigger_tokens_ht_element
->node
);
3187 call_rcu(&trigger_tokens_ht_element
->rcu_node
,
3188 free_notification_trigger_tokens_ht_element_rcu
);
3195 void remove_trigger_from_session_trigger_list(
3196 struct lttng_session_trigger_list
*trigger_list
,
3197 const struct lttng_trigger
*trigger
)
3200 struct lttng_trigger_list_element
*trigger_element
, *tmp
;
3202 cds_list_for_each_entry_safe (trigger_element
, tmp
, &trigger_list
->list
, node
) {
3203 if (!lttng_trigger_is_equal(trigger
, trigger_element
->trigger
)) {
3207 DBG("Removed trigger from session_triggers_ht");
3208 cds_list_del(&trigger_element
->node
);
3209 free(trigger_element
);
3210 /* A trigger can only appear once per session. */
3216 ERR("Failed to find trigger associated with session: session name = `%s`",
3217 trigger_list
->session_name
);
3220 LTTNG_ASSERT(found
);
3224 int handle_notification_thread_command_unregister_trigger(
3225 struct notification_thread_state
*state
,
3226 const struct lttng_trigger
*trigger
,
3227 enum lttng_error_code
*_cmd_reply
)
3229 struct cds_lfht_iter iter
;
3230 struct cds_lfht_node
*triggers_ht_node
;
3231 struct notification_client_list
*client_list
;
3232 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
3233 const struct lttng_condition
*condition
= lttng_trigger_get_const_condition(
3235 enum lttng_error_code cmd_reply
;
3239 cds_lfht_lookup(state
->triggers_ht
,
3240 lttng_condition_hash(condition
),
3244 triggers_ht_node
= cds_lfht_iter_get_node(&iter
);
3245 if (!triggers_ht_node
) {
3246 cmd_reply
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
3249 cmd_reply
= LTTNG_OK
;
3252 trigger_ht_element
= caa_container_of(triggers_ht_node
,
3253 struct lttng_trigger_ht_element
, node
);
3255 switch (get_condition_binding_object(condition
)) {
3256 case LTTNG_OBJECT_TYPE_CHANNEL
:
3258 struct lttng_channel_trigger_list
*trigger_list
;
3261 * Remove trigger from channel_triggers_ht.
3263 * Note that multiple channels may have matched the trigger's
3264 * condition (e.g. all instances of a given channel in per-pid buffering
3267 * Iterate on all lists since we don't know the target channels' keys.
3269 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
, trigger_list
,
3270 channel_triggers_ht_node
) {
3271 struct lttng_trigger_list_element
*trigger_element
, *tmp
;
3273 cds_list_for_each_entry_safe(
3274 trigger_element
, tmp
, &trigger_list
->list
, node
) {
3275 if (!lttng_trigger_is_equal(trigger
, trigger_element
->trigger
)) {
3279 DBG("Removed trigger from channel_triggers_ht");
3280 cds_list_del(&trigger_element
->node
);
3281 free(trigger_element
);
3282 /* A trigger can only appear once per channel */
3288 case LTTNG_OBJECT_TYPE_SESSION
:
3290 auto session
= get_session_info_by_name(
3291 state
, get_condition_session_name(condition
));
3293 /* Session doesn't exist, no trigger to remove. */
3298 auto session_trigger_list
= get_session_trigger_list(state
, session
->name
);
3299 remove_trigger_from_session_trigger_list(session_trigger_list
, trigger
);
3300 session_info_put(session
);
3302 case LTTNG_OBJECT_TYPE_NONE
:
3308 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
3309 teardown_tracer_notifier(state
, trigger
);
3312 if (is_trigger_action_notify(trigger
)) {
3314 * Remove and release the client list from
3315 * notification_trigger_clients_ht.
3317 client_list
= get_client_list_from_condition(state
, condition
);
3318 LTTNG_ASSERT(client_list
);
3320 pthread_mutex_lock(&client_list
->lock
);
3321 cds_list_del(&trigger_ht_element
->client_list_trigger_node
);
3322 pthread_mutex_unlock(&client_list
->lock
);
3324 /* Put new reference and the hashtable's reference. */
3325 notification_client_list_put(client_list
);
3326 notification_client_list_put(client_list
);
3330 /* Remove trigger from triggers_ht. */
3331 notif_thread_state_remove_trigger_ht_elem(state
, trigger_ht_element
);
3333 /* Release the ownership of the trigger. */
3334 lttng_trigger_destroy(trigger_ht_element
->trigger
);
3335 call_rcu(&trigger_ht_element
->rcu_node
, free_lttng_trigger_ht_element_rcu
);
3339 *_cmd_reply
= cmd_reply
;
3345 int pop_cmd_queue(struct notification_thread_handle
*handle
,
3346 struct notification_thread_command
**cmd
)
3351 pthread_mutex_lock(&handle
->cmd_queue
.lock
);
3352 ret
= lttng_read(handle
->cmd_queue
.event_fd
, &counter
, sizeof(counter
));
3353 if (ret
!= sizeof(counter
)) {
3358 *cmd
= cds_list_first_entry(&handle
->cmd_queue
.list
,
3359 struct notification_thread_command
, cmd_list_node
);
3360 cds_list_del(&((*cmd
)->cmd_list_node
));
3364 pthread_mutex_unlock(&handle
->cmd_queue
.lock
);
3368 /* Returns 0 on success, 1 on exit requested, negative value on error. */
3369 int handle_notification_thread_command(
3370 struct notification_thread_handle
*handle
,
3371 struct notification_thread_state
*state
)
3374 struct notification_thread_command
*cmd
;
3376 ret
= pop_cmd_queue(handle
, &cmd
);
3381 DBG("Received `%s` command",
3382 notification_command_type_str(cmd
->type
));
3383 switch (cmd
->type
) {
3384 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
3385 ret
= handle_notification_thread_command_register_trigger(state
,
3386 cmd
->parameters
.register_trigger
.trigger
,
3387 cmd
->parameters
.register_trigger
.is_trigger_anonymous
,
3390 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
3391 ret
= handle_notification_thread_command_unregister_trigger(
3393 cmd
->parameters
.unregister_trigger
.trigger
,
3396 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
3397 ret
= handle_notification_thread_command_add_channel(
3399 cmd
->parameters
.add_channel
.session
.id
,
3400 cmd
->parameters
.add_channel
.channel
.name
,
3401 cmd
->parameters
.add_channel
.channel
.domain
,
3402 cmd
->parameters
.add_channel
.channel
.key
,
3403 cmd
->parameters
.add_channel
.channel
.capacity
,
3406 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
3407 ret
= handle_notification_thread_command_remove_channel(
3408 state
, cmd
->parameters
.remove_channel
.key
,
3409 cmd
->parameters
.remove_channel
.domain
,
3412 case NOTIFICATION_COMMAND_TYPE_ADD_SESSION
:
3413 ret
= handle_notification_thread_command_add_session(state
,
3414 cmd
->parameters
.add_session
.session_id
,
3415 cmd
->parameters
.add_session
.session_name
,
3416 cmd
->parameters
.add_session
.session_uid
,
3417 cmd
->parameters
.add_session
.session_gid
, &cmd
->reply_code
);
3419 case NOTIFICATION_COMMAND_TYPE_REMOVE_SESSION
:
3420 ret
= handle_notification_thread_command_remove_session(
3421 state
, cmd
->parameters
.remove_session
.session_id
, &cmd
->reply_code
);
3423 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
3424 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
3425 ret
= handle_notification_thread_command_session_rotation(
3428 cmd
->parameters
.session_rotation
.session_id
,
3429 cmd
->parameters
.session_rotation
.trace_archive_chunk_id
,
3430 cmd
->parameters
.session_rotation
.location
,
3433 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
3434 ret
= handle_notification_thread_command_add_tracer_event_source(
3436 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3437 cmd
->parameters
.tracer_event_source
.domain
,
3440 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
3441 ret
= handle_notification_thread_command_remove_tracer_event_source(
3443 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3446 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
3448 struct lttng_triggers
*triggers
= NULL
;
3450 ret
= handle_notification_thread_command_list_triggers(
3453 cmd
->parameters
.list_triggers
.uid
,
3456 cmd
->reply
.list_triggers
.triggers
= triggers
;
3460 case NOTIFICATION_COMMAND_TYPE_QUIT
:
3461 cmd
->reply_code
= LTTNG_OK
;
3464 case NOTIFICATION_COMMAND_TYPE_GET_TRIGGER
:
3466 struct lttng_trigger
*trigger
= NULL
;
3468 ret
= handle_notification_thread_command_get_trigger(state
,
3469 cmd
->parameters
.get_trigger
.trigger
, &trigger
,
3471 cmd
->reply
.get_trigger
.trigger
= trigger
;
3474 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
3476 const enum client_transmission_status client_status
=
3477 cmd
->parameters
.client_communication_update
3479 const notification_client_id client_id
=
3480 cmd
->parameters
.client_communication_update
.id
;
3481 struct notification_client
*client
;
3484 client
= get_client_from_id(client_id
, state
);
3488 * Client error was probably already picked-up by the
3489 * notification thread or it has disconnected
3490 * gracefully while this command was queued.
3492 DBG("Failed to find notification client to update communication status, client id = %" PRIu64
,
3496 ret
= client_handle_transmission_status(
3497 client
, client_status
, state
);
3503 ERR("Unknown internal command received");
3511 if (cmd
->is_async
) {
3515 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3519 /* Wake-up and return a fatal error to the calling thread. */
3520 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3521 cmd
->reply_code
= LTTNG_ERR_FATAL
;
3523 /* Indicate a fatal error to the caller. */
3528 int socket_set_non_blocking(int socket
)
3532 /* Set the pipe as non-blocking. */
3533 ret
= fcntl(socket
, F_GETFL
, 0);
3535 PERROR("fcntl get socket flags");
3540 ret
= fcntl(socket
, F_SETFL
, flags
| O_NONBLOCK
);
3542 PERROR("fcntl set O_NONBLOCK socket flag");
3545 DBG("Client socket (fd = %i) set as non-blocking", socket
);
3551 int client_reset_inbound_state(struct notification_client
*client
)
3556 lttng_payload_clear(&client
->communication
.inbound
.payload
);
3558 client
->communication
.inbound
.bytes_to_receive
=
3559 sizeof(struct lttng_notification_channel_message
);
3560 client
->communication
.inbound
.msg_type
=
3561 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
;
3562 LTTNG_SOCK_SET_UID_CRED(&client
->communication
.inbound
.creds
, -1);
3563 LTTNG_SOCK_SET_GID_CRED(&client
->communication
.inbound
.creds
, -1);
3564 ret
= lttng_dynamic_buffer_set_size(
3565 &client
->communication
.inbound
.payload
.buffer
,
3566 client
->communication
.inbound
.bytes_to_receive
);
3571 int handle_notification_thread_client_connect(
3572 struct notification_thread_state
*state
)
3575 struct notification_client
*client
;
3577 DBG("Handling new notification channel client connection");
3579 client
= zmalloc
<notification_client
>();
3586 pthread_mutex_init(&client
->lock
, NULL
);
3587 client
->id
= state
->next_notification_client_id
++;
3588 CDS_INIT_LIST_HEAD(&client
->condition_list
);
3589 lttng_payload_init(&client
->communication
.inbound
.payload
);
3590 lttng_payload_init(&client
->communication
.outbound
.payload
);
3591 client
->communication
.inbound
.expect_creds
= true;
3593 ret
= client_reset_inbound_state(client
);
3595 ERR("Failed to reset client communication's inbound state");
3600 ret
= lttcomm_accept_unix_sock(state
->notification_channel_socket
);
3602 ERR("Failed to accept new notification channel client connection");
3607 client
->socket
= ret
;
3609 ret
= socket_set_non_blocking(client
->socket
);
3611 ERR("Failed to set new notification channel client connection socket as non-blocking");
3615 ret
= lttcomm_setsockopt_creds_unix_sock(client
->socket
);
3617 ERR("Failed to set socket options on new notification channel client socket");
3622 client
->communication
.current_poll_events
= CLIENT_POLL_EVENTS_IN
;
3623 ret
= lttng_poll_add(&state
->events
, client
->socket
,
3624 client
->communication
.current_poll_events
);
3626 ERR("Failed to add notification channel client socket to poll set");
3630 DBG("Added new notification channel client socket (%i) to poll set",
3634 cds_lfht_add(state
->client_socket_ht
,
3635 hash_client_socket(client
->socket
),
3636 &client
->client_socket_ht_node
);
3637 cds_lfht_add(state
->client_id_ht
,
3638 hash_client_id(client
->id
),
3639 &client
->client_id_ht_node
);
3645 notification_client_destroy(client
);
3650 * RCU read-lock must be held by the caller.
3651 * Client lock must _not_ be held by the caller.
3654 int notification_thread_client_disconnect(
3655 struct notification_client
*client
,
3656 struct notification_thread_state
*state
)
3659 struct lttng_condition_list_element
*condition_list_element
, *tmp
;
3661 ASSERT_RCU_READ_LOCKED();
3663 /* Acquire the client lock to disable its communication atomically. */
3664 pthread_mutex_lock(&client
->lock
);
3665 client
->communication
.active
= false;
3666 cds_lfht_del(state
->client_socket_ht
, &client
->client_socket_ht_node
);
3667 cds_lfht_del(state
->client_id_ht
, &client
->client_id_ht_node
);
3668 pthread_mutex_unlock(&client
->lock
);
3670 ret
= lttng_poll_del(&state
->events
, client
->socket
);
3672 ERR("Failed to remove client socket %d from poll set",
3676 /* Release all conditions to which the client was subscribed. */
3677 cds_list_for_each_entry_safe(condition_list_element
, tmp
,
3678 &client
->condition_list
, node
) {
3679 (void) notification_thread_client_unsubscribe(client
,
3680 condition_list_element
->condition
, state
, NULL
);
3684 * Client no longer accessible to other threads (through the
3687 notification_client_destroy(client
);
3691 int handle_notification_thread_client_disconnect(
3692 int client_socket
, struct notification_thread_state
*state
)
3695 struct notification_client
*client
;
3698 DBG("Closing client connection (socket fd = %i)",
3700 client
= get_client_from_socket(client_socket
, state
);
3702 /* Internal state corruption, fatal error. */
3703 ERR("Unable to find client (socket fd = %i)",
3709 ret
= notification_thread_client_disconnect(client
, state
);
3715 int handle_notification_thread_client_disconnect_all(
3716 struct notification_thread_state
*state
)
3718 struct cds_lfht_iter iter
;
3719 struct notification_client
*client
;
3720 bool error_encoutered
= false;
3723 DBG("Closing all client connections");
3724 cds_lfht_for_each_entry(state
->client_socket_ht
, &iter
, client
,
3725 client_socket_ht_node
) {
3728 ret
= notification_thread_client_disconnect(
3731 error_encoutered
= true;
3735 return error_encoutered
? 1 : 0;
3738 int handle_notification_thread_trigger_unregister_all(
3739 struct notification_thread_state
*state
)
3741 bool error_occurred
= false;
3742 struct cds_lfht_iter iter
;
3743 struct lttng_trigger_ht_element
*trigger_ht_element
;
3746 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
3748 int ret
= handle_notification_thread_command_unregister_trigger(
3749 state
, trigger_ht_element
->trigger
, NULL
);
3751 error_occurred
= true;
3755 return error_occurred
? -1 : 0;
3759 bool client_has_outbound_data_left(
3760 const struct notification_client
*client
)
3762 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3763 &client
->communication
.outbound
.payload
, 0, -1);
3764 const bool has_data
= pv
.buffer
.size
!= 0;
3765 const bool has_fds
= lttng_payload_view_get_fd_handle_count(&pv
);
3767 return has_data
|| has_fds
;
3771 int client_handle_transmission_status(
3772 struct notification_client
*client
,
3773 enum client_transmission_status transmission_status
,
3774 struct notification_thread_state
*state
)
3778 switch (transmission_status
) {
3779 case CLIENT_TRANSMISSION_STATUS_COMPLETE
:
3780 case CLIENT_TRANSMISSION_STATUS_QUEUED
:
3782 int current_poll_events
;
3783 int new_poll_events
;
3785 * We want to be notified whenever there is buffer space
3786 * available to send the rest of the payload if we are
3787 * waiting to send data to the client.
3789 * The state of the outbound queue being sampled here is
3791 * - it is okay to wake-up "for nothing" in case we see
3792 * that data is left, but another thread succeeds in
3793 * flushing it before us when handling the client "out"
3794 * event. We will simply stop monitoring that event the next
3795 * time it wakes us up and we see no data left to be sent,
3796 * - if another thread fails to flush the entire client
3797 * outgoing queue, it will issue a "communication update"
3798 * command and cause the client's (e)poll mask to be
3801 * The situation we seek to avoid would be to disable the
3802 * monitoring of "out" client events indefinitely when there is
3803 * data to be sent, which can't happen because of the
3804 * aforementioned "communication update" mechanism.
3806 pthread_mutex_lock(&client
->lock
);
3807 current_poll_events
= client
->communication
.current_poll_events
;
3808 new_poll_events
= client_has_outbound_data_left(client
) ?
3809 CLIENT_POLL_EVENTS_IN_OUT
:
3810 CLIENT_POLL_EVENTS_IN
;
3811 client
->communication
.current_poll_events
= new_poll_events
;
3812 pthread_mutex_unlock(&client
->lock
);
3814 /* Update the monitored event set only if it changed. */
3815 if (current_poll_events
!= new_poll_events
) {
3816 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3825 case CLIENT_TRANSMISSION_STATUS_FAIL
:
3826 ret
= notification_thread_client_disconnect(client
, state
);
3831 case CLIENT_TRANSMISSION_STATUS_ERROR
:
3841 /* Client lock must be acquired by caller. */
3843 enum client_transmission_status
client_flush_outgoing_queue(
3844 struct notification_client
*client
)
3847 size_t to_send_count
;
3848 enum client_transmission_status status
;
3849 struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3850 &client
->communication
.outbound
.payload
, 0, -1);
3851 const int fds_to_send_count
=
3852 lttng_payload_view_get_fd_handle_count(&pv
);
3854 ASSERT_LOCKED(client
->lock
);
3856 if (!client
->communication
.active
) {
3857 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3861 if (pv
.buffer
.size
== 0) {
3863 * If both data and fds are equal to zero, we are in an invalid
3866 LTTNG_ASSERT(fds_to_send_count
!= 0);
3871 to_send_count
= pv
.buffer
.size
;
3872 DBG("Flushing client (socket fd = %i) outgoing queue",
3875 ret
= lttcomm_send_unix_sock_non_block(client
->socket
,
3878 if ((ret
>= 0 && ret
< to_send_count
)) {
3879 DBG("Client (socket fd = %i) outgoing queue could not be completely flushed",
3881 to_send_count
-= std::max(ret
, (ssize_t
) 0);
3883 memmove(client
->communication
.outbound
.payload
.buffer
.data
,
3885 pv
.buffer
.size
- to_send_count
,
3887 ret
= lttng_dynamic_buffer_set_size(
3888 &client
->communication
.outbound
.payload
.buffer
,
3894 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3896 } else if (ret
< 0) {
3897 /* Generic error, disable the client's communication. */
3898 ERR("Failed to flush outgoing queue, disconnecting client (socket fd = %i)",
3900 client
->communication
.active
= false;
3901 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3905 * No error and flushed the queue completely.
3907 * The payload buffer size is used later to
3908 * check if there is notifications queued. So albeit that the
3909 * direct caller knows that the transmission is complete, we
3910 * need to set the buffer size to zero.
3912 ret
= lttng_dynamic_buffer_set_size(
3913 &client
->communication
.outbound
.payload
.buffer
, 0);
3920 /* No fds to send, transmission is complete. */
3921 if (fds_to_send_count
== 0) {
3922 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3926 ret
= lttcomm_send_payload_view_fds_unix_sock_non_block(
3927 client
->socket
, &pv
);
3929 /* Generic error, disable the client's communication. */
3930 ERR("Failed to flush outgoing fds queue, disconnecting client (socket fd = %i)",
3932 client
->communication
.active
= false;
3933 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3935 } else if (ret
== 0) {
3936 /* Nothing could be sent. */
3937 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3939 /* Fd passing is an all or nothing kind of thing. */
3940 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3942 * The payload _fd_array count is used later to
3943 * check if there is notifications queued. So although the
3944 * direct caller knows that the transmission is complete, we
3945 * need to clear the _fd_array for the queuing check.
3947 lttng_dynamic_pointer_array_clear(
3948 &client
->communication
.outbound
.payload
3953 if (status
== CLIENT_TRANSMISSION_STATUS_COMPLETE
) {
3954 client
->communication
.outbound
.queued_command_reply
= false;
3955 client
->communication
.outbound
.dropped_notification
= false;
3956 lttng_payload_clear(&client
->communication
.outbound
.payload
);
3961 return CLIENT_TRANSMISSION_STATUS_ERROR
;
3964 /* Client lock must _not_ be held by the caller. */
3966 int client_send_command_reply(struct notification_client
*client
,
3967 struct notification_thread_state
*state
,
3968 enum lttng_notification_channel_status status
)
3971 struct lttng_notification_channel_command_reply reply
= {
3972 .status
= (int8_t) status
,
3974 struct lttng_notification_channel_message msg
;
3975 char buffer
[sizeof(msg
) + sizeof(reply
)];
3976 enum client_transmission_status transmission_status
;
3978 msg
.type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY
;
3979 msg
.size
= sizeof(reply
);
3982 memcpy(buffer
, &msg
, sizeof(msg
));
3983 memcpy(buffer
+ sizeof(msg
), &reply
, sizeof(reply
));
3984 DBG("Send command reply (%i)", (int) status
);
3986 pthread_mutex_lock(&client
->lock
);
3987 if (client
->communication
.outbound
.queued_command_reply
) {
3988 /* Protocol error. */
3992 /* Enqueue buffer to outgoing queue and flush it. */
3993 ret
= lttng_dynamic_buffer_append(
3994 &client
->communication
.outbound
.payload
.buffer
,
3995 buffer
, sizeof(buffer
));
4000 transmission_status
= client_flush_outgoing_queue(client
);
4002 if (client_has_outbound_data_left(client
)) {
4003 /* Queue could not be emptied. */
4004 client
->communication
.outbound
.queued_command_reply
= true;
4007 pthread_mutex_unlock(&client
->lock
);
4008 ret
= client_handle_transmission_status(
4009 client
, transmission_status
, state
);
4016 pthread_mutex_unlock(&client
->lock
);
4022 int client_handle_message_unknown(struct notification_client
*client
,
4023 struct notification_thread_state
*state
__attribute__((unused
)))
4027 * Receiving message header. The function will be called again
4028 * once the rest of the message as been received and can be
4031 const struct lttng_notification_channel_message
*msg
;
4033 LTTNG_ASSERT(sizeof(*msg
) == client
->communication
.inbound
.payload
.buffer
.size
);
4034 msg
= (const struct lttng_notification_channel_message
*)
4035 client
->communication
.inbound
.payload
.buffer
.data
;
4037 if (msg
->size
== 0 ||
4038 msg
->size
> DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE
) {
4039 ERR("Invalid notification channel message: length = %u",
4045 switch (msg
->type
) {
4046 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
4047 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
4048 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
4052 ERR("Invalid notification channel message: unexpected message type");
4056 client
->communication
.inbound
.bytes_to_receive
= msg
->size
;
4057 client
->communication
.inbound
.fds_to_receive
= msg
->fds
;
4058 client
->communication
.inbound
.msg_type
=
4059 (enum lttng_notification_channel_message_type
) msg
->type
;
4060 ret
= lttng_dynamic_buffer_set_size(
4061 &client
->communication
.inbound
.payload
.buffer
, msg
->size
);
4063 /* msg is not valid anymore due to lttng_dynamic_buffer_set_size. */
4070 int client_handle_message_handshake(struct notification_client
*client
,
4071 struct notification_thread_state
*state
)
4074 struct lttng_notification_channel_command_handshake
*handshake_client
;
4075 const struct lttng_notification_channel_command_handshake handshake_reply
= {
4076 .major
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
,
4077 .minor
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR
,
4079 struct lttng_notification_channel_message msg_header
;
4080 enum lttng_notification_channel_status status
=
4081 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
4082 char send_buffer
[sizeof(msg_header
) + sizeof(handshake_reply
)];
4084 msg_header
.type
= LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
;
4085 msg_header
.size
= sizeof(handshake_reply
);
4088 memcpy(send_buffer
, &msg_header
, sizeof(msg_header
));
4089 memcpy(send_buffer
+ sizeof(msg_header
), &handshake_reply
,
4090 sizeof(handshake_reply
));
4093 (struct lttng_notification_channel_command_handshake
*)
4094 client
->communication
.inbound
.payload
.buffer
4096 client
->major
= handshake_client
->major
;
4097 client
->minor
= handshake_client
->minor
;
4098 if (!client
->communication
.inbound
.creds_received
) {
4099 ERR("No credentials received from client");
4104 client
->uid
= LTTNG_SOCK_GET_UID_CRED(
4105 &client
->communication
.inbound
.creds
);
4106 client
->gid
= LTTNG_SOCK_GET_GID_CRED(
4107 &client
->communication
.inbound
.creds
);
4108 client
->is_sessiond
= LTTNG_SOCK_GET_PID_CRED(&client
->communication
.inbound
.creds
) == getpid();
4109 DBG("Received handshake from client: uid = %u, gid = %u, protocol version = %i.%i, client is sessiond = %s",
4110 client
->uid
, client
->gid
, (int) client
->major
,
4111 (int) client
->minor
,
4112 client
->is_sessiond
? "true" : "false");
4114 if (handshake_client
->major
!=
4115 LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
) {
4116 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION
;
4119 pthread_mutex_lock(&client
->lock
);
4120 /* Outgoing queue will be flushed when the command reply is sent. */
4121 ret
= lttng_dynamic_buffer_append(
4122 &client
->communication
.outbound
.payload
.buffer
, send_buffer
,
4123 sizeof(send_buffer
));
4125 ERR("Failed to send protocol version to notification channel client");
4129 client
->validated
= true;
4130 client
->communication
.active
= true;
4131 pthread_mutex_unlock(&client
->lock
);
4133 /* Set reception state to receive the next message header. */
4134 ret
= client_reset_inbound_state(client
);
4136 ERR("Failed to reset client communication's inbound state");
4140 /* Flushes the outgoing queue. */
4141 ret
= client_send_command_reply(client
, state
, status
);
4143 ERR("Failed to send reply to notification channel client");
4149 pthread_mutex_unlock(&client
->lock
);
4155 int client_handle_message_subscription(
4156 struct notification_client
*client
,
4157 enum lttng_notification_channel_message_type msg_type
,
4158 struct notification_thread_state
*state
)
4161 struct lttng_condition
*condition
;
4162 enum lttng_notification_channel_status status
=
4163 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
4164 struct lttng_payload_view condition_view
=
4165 lttng_payload_view_from_payload(
4166 &client
->communication
.inbound
.payload
,
4168 size_t expected_condition_size
;
4171 * No need to lock client to sample the inbound state as the only
4172 * other thread accessing clients (action executor) only uses the
4175 expected_condition_size
= client
->communication
.inbound
.payload
.buffer
.size
;
4176 ret
= lttng_condition_create_from_payload(&condition_view
, &condition
);
4177 if (ret
!= expected_condition_size
) {
4178 ERR("Malformed condition received from client");
4182 /* Ownership of condition is always transferred. */
4183 if (msg_type
== LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
) {
4184 ret
= notification_thread_client_subscribe(
4185 client
, condition
, state
, &status
);
4187 ret
= notification_thread_client_unsubscribe(
4188 client
, condition
, state
, &status
);
4195 /* Set reception state to receive the next message header. */
4196 ret
= client_reset_inbound_state(client
);
4198 ERR("Failed to reset client communication's inbound state");
4202 ret
= client_send_command_reply(client
, state
, status
);
4204 ERR("Failed to send reply to notification channel client");
4213 int client_dispatch_message(struct notification_client
*client
,
4214 struct notification_thread_state
*state
)
4218 if (client
->communication
.inbound
.msg_type
!=
4219 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
&&
4220 client
->communication
.inbound
.msg_type
!=
4221 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
&&
4222 !client
->validated
) {
4223 WARN("client attempted a command before handshake");
4228 switch (client
->communication
.inbound
.msg_type
) {
4229 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
:
4231 ret
= client_handle_message_unknown(client
, state
);
4234 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
4236 ret
= client_handle_message_handshake(client
, state
);
4239 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
4240 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
4242 ret
= client_handle_message_subscription(client
,
4243 client
->communication
.inbound
.msg_type
, state
);
4253 /* Incoming data from client. */
4254 int handle_notification_thread_client_in(
4255 struct notification_thread_state
*state
, int socket
)
4258 struct notification_client
*client
;
4263 client
= get_client_from_socket(socket
, state
);
4265 /* Internal error, abort. */
4270 if (client
->communication
.inbound
.bytes_to_receive
== 0 &&
4271 client
->communication
.inbound
.fds_to_receive
!= 0) {
4272 /* Only FDs left to receive. */
4276 offset
= client
->communication
.inbound
.payload
.buffer
.size
-
4277 client
->communication
.inbound
.bytes_to_receive
;
4278 if (client
->communication
.inbound
.expect_creds
) {
4279 recv_ret
= lttcomm_recv_creds_unix_sock(socket
,
4280 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
4281 client
->communication
.inbound
.bytes_to_receive
,
4282 &client
->communication
.inbound
.creds
);
4284 client
->communication
.inbound
.expect_creds
= false;
4285 client
->communication
.inbound
.creds_received
= true;
4288 recv_ret
= lttcomm_recv_unix_sock_non_block(socket
,
4289 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
4290 client
->communication
.inbound
.bytes_to_receive
);
4292 if (recv_ret
>= 0) {
4293 client
->communication
.inbound
.bytes_to_receive
-= recv_ret
;
4295 goto error_disconnect_client
;
4298 if (client
->communication
.inbound
.bytes_to_receive
!= 0) {
4299 /* Message incomplete wait for more data. */
4305 LTTNG_ASSERT(client
->communication
.inbound
.bytes_to_receive
== 0);
4308 if (client
->communication
.inbound
.fds_to_receive
!= 0) {
4309 ret
= lttcomm_recv_payload_fds_unix_sock_non_block(
4311 client
->communication
.inbound
.fds_to_receive
,
4312 &client
->communication
.inbound
.payload
);
4315 * Fds received. non blocking fds passing is all
4318 ssize_t expected_size
;
4320 expected_size
= sizeof(int) *
4321 client
->communication
.inbound
4323 LTTNG_ASSERT(ret
== expected_size
);
4324 client
->communication
.inbound
.fds_to_receive
= 0;
4325 } else if (ret
== 0) {
4326 /* Received nothing. */
4330 goto error_disconnect_client
;
4334 /* At this point the message is complete.*/
4335 LTTNG_ASSERT(client
->communication
.inbound
.bytes_to_receive
== 0 &&
4336 client
->communication
.inbound
.fds_to_receive
== 0);
4337 ret
= client_dispatch_message(client
, state
);
4340 * Only returns an error if this client must be
4343 goto error_disconnect_client
;
4350 error_disconnect_client
:
4351 ret
= notification_thread_client_disconnect(client
, state
);
4355 /* Client ready to receive outgoing data. */
4356 int handle_notification_thread_client_out(
4357 struct notification_thread_state
*state
, int socket
)
4360 struct notification_client
*client
;
4361 enum client_transmission_status transmission_status
;
4364 client
= get_client_from_socket(socket
, state
);
4366 /* Internal error, abort. */
4371 pthread_mutex_lock(&client
->lock
);
4372 if (!client_has_outbound_data_left(client
)) {
4374 * A client "out" event can be received when no payload is left
4375 * to send under some circumstances.
4377 * Many threads can flush a client's outgoing queue and, if they
4378 * had to queue their message (socket was full), will use the
4379 * "communication update" command to signal the (e)poll thread
4380 * to monitor for space being made available in the socket.
4382 * Commands are sent over an internal pipe serviced by the same
4383 * thread as the client sockets.
4385 * When space is made available in the socket, there is a race
4386 * between the (e)poll thread and the other threads that may
4387 * wish to use the client's socket to flush its outgoing queue.
4389 * A non-(e)poll thread may attempt (and succeed) in flushing
4390 * the queue before the (e)poll thread gets a chance to service
4391 * the client's "out" event.
4393 * In this situation, the (e)poll thread processing the client
4394 * out event will see an empty payload: there is nothing to do
4395 * except unsubscribing (e)poll "out" events.
4397 * Note that this thread is the (e)poll thread so it can modify
4398 * the (e)poll mask directly without using a communication
4399 * update command. Other threads that flush the outgoing queue
4400 * will use the "communication update" command to wake up this
4401 * thread and force it to monitor "out" events.
4403 * When other threads succeed in emptying the outgoing queue,
4404 * they don't need to update the (e)poll mask: if the "out"
4405 * event is monitored, it will fire once and the (e)poll
4406 * thread will reach this condition, causing the event to
4407 * stop being monitored.
4409 transmission_status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
4411 transmission_status
= client_flush_outgoing_queue(client
);
4413 pthread_mutex_unlock(&client
->lock
);
4415 ret
= client_handle_transmission_status(
4416 client
, transmission_status
, state
);
4426 bool evaluate_buffer_usage_condition(const struct lttng_condition
*condition
,
4427 const struct channel_state_sample
*sample
,
4428 uint64_t buffer_capacity
)
4430 bool result
= false;
4432 enum lttng_condition_type condition_type
;
4433 const struct lttng_condition_buffer_usage
*use_condition
= lttng::utils::container_of(
4434 condition
, <tng_condition_buffer_usage::parent
);
4436 if (use_condition
->threshold_bytes
.set
) {
4437 threshold
= use_condition
->threshold_bytes
.value
;
4440 * Threshold was expressed as a ratio.
4442 * TODO the threshold (in bytes) of conditions expressed
4443 * as a ratio of total buffer size could be cached to
4444 * forego this double-multiplication or it could be performed
4445 * as fixed-point math.
4447 * Note that caching should accommodates the case where the
4448 * condition applies to multiple channels (i.e. don't assume
4449 * that all channels matching my_chann* have the same size...)
4451 threshold
= (uint64_t) (use_condition
->threshold_ratio
.value
*
4452 (double) buffer_capacity
);
4455 condition_type
= lttng_condition_get_type(condition
);
4456 if (condition_type
== LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
) {
4457 DBG("Low buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4458 threshold
, sample
->highest_usage
);
4461 * The low condition should only be triggered once _all_ of the
4462 * streams in a channel have gone below the "low" threshold.
4464 if (sample
->highest_usage
<= threshold
) {
4468 DBG("High buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4469 threshold
, sample
->highest_usage
);
4472 * For high buffer usage scenarios, we want to trigger whenever
4473 * _any_ of the streams has reached the "high" threshold.
4475 if (sample
->highest_usage
>= threshold
) {
4484 int evaluate_buffer_condition(const struct lttng_condition
*condition
,
4485 struct lttng_evaluation
**evaluation
,
4486 const struct notification_thread_state
*state
__attribute__((unused
)),
4487 const struct channel_state_sample
*previous_sample
,
4488 const struct channel_state_sample
*latest_sample
,
4489 struct channel_info
*channel_info
)
4492 enum lttng_condition_type condition_type
;
4493 const bool previous_sample_available
= !!previous_sample
;
4494 bool previous_sample_result
= false;
4495 bool latest_sample_result
;
4497 condition_type
= lttng_condition_get_type(condition
);
4499 switch (condition_type
) {
4500 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4501 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4502 if (caa_likely(previous_sample_available
)) {
4503 previous_sample_result
=
4504 evaluate_buffer_usage_condition(condition
,
4505 previous_sample
, channel_info
->capacity
);
4507 latest_sample_result
= evaluate_buffer_usage_condition(
4508 condition
, latest_sample
,
4509 channel_info
->capacity
);
4512 /* Unknown condition type; internal error. */
4516 if (!latest_sample_result
||
4517 (previous_sample_result
== latest_sample_result
)) {
4519 * Only trigger on a condition evaluation transition.
4521 * NOTE: This edge-triggered logic may not be appropriate for
4522 * future condition types.
4527 if (!evaluation
|| !latest_sample_result
) {
4531 switch (condition_type
) {
4532 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4533 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4534 *evaluation
= lttng_evaluation_buffer_usage_create(
4536 latest_sample
->highest_usage
,
4537 channel_info
->capacity
);
4552 int client_notification_overflow(struct notification_client
*client
)
4555 struct lttng_notification_channel_message msg
;
4557 msg
.type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED
;
4561 ASSERT_LOCKED(client
->lock
);
4563 DBG("Dropping notification addressed to client (socket fd = %i)",
4565 if (client
->communication
.outbound
.dropped_notification
) {
4567 * The client already has a "notification dropped" message
4568 * in its outgoing queue. Nothing to do since all
4569 * of those messages are coalesced.
4574 client
->communication
.outbound
.dropped_notification
= true;
4575 ret
= lttng_dynamic_buffer_append(
4576 &client
->communication
.outbound
.payload
.buffer
, &msg
,
4579 PERROR("Failed to enqueue \"dropped notification\" message in client's (socket fd = %i) outgoing queue",
4586 static int client_handle_transmission_status_wrapper(
4587 struct notification_client
*client
,
4588 enum client_transmission_status status
,
4591 return client_handle_transmission_status(client
, status
,
4592 (struct notification_thread_state
*) user_data
);
4596 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
4597 const struct lttng_evaluation
*evaluation
,
4598 struct notification_client_list
* client_list
,
4599 struct notification_thread_state
*state
,
4600 uid_t object_uid
, gid_t object_gid
)
4602 const struct lttng_credentials creds
= {
4603 .uid
= LTTNG_OPTIONAL_INIT_VALUE(object_uid
),
4604 .gid
= LTTNG_OPTIONAL_INIT_VALUE(object_gid
),
4607 return notification_client_list_send_evaluation(client_list
,
4608 trigger
, evaluation
,
4610 client_handle_transmission_status_wrapper
, state
);
4614 * Permission checks relative to notification channel clients are performed
4615 * here. Notice how object, client, and trigger credentials are involved in
4618 * The `object` credentials are the credentials associated with the "subject"
4619 * of a condition. For instance, a `rotation completed` condition applies
4620 * to a session. When that condition is met, it will produce an evaluation
4621 * against a session. Hence, in this case, the `object` credentials are the
4622 * credentials of the "subject" session.
4624 * The `trigger` credentials are the credentials of the user that registered the
4627 * The `client` credentials are the credentials of the user that created a given
4628 * notification channel.
4630 * In terms of visibility, it is expected that non-privilieged users can only
4631 * register triggers against "their" objects (their own sessions and
4632 * applications they are allowed to interact with). They can then open a
4633 * notification channel and subscribe to notifications associated with those
4636 * As for privilieged users, they can register triggers against the objects of
4637 * other users. They can then subscribe to the notifications associated to their
4638 * triggers. Privilieged users _can't_ subscribe to the notifications of
4639 * triggers owned by other users; they must create their own triggers.
4641 * This is more a concern of usability than security. It would be difficult for
4642 * a root user reliably subscribe to a specific set of conditions without
4643 * interference from external users (those could, for instance, unregister
4646 int notification_client_list_send_evaluation(
4647 struct notification_client_list
*client_list
,
4648 const struct lttng_trigger
*trigger
,
4649 const struct lttng_evaluation
*evaluation
,
4650 const struct lttng_credentials
*source_object_creds
,
4651 report_client_transmission_result_cb client_report
,
4655 struct lttng_payload msg_payload
;
4656 struct notification_client_list_element
*client_list_element
, *tmp
;
4657 const struct lttng_notification notification
= {
4658 .trigger
= (struct lttng_trigger
*) trigger
,
4659 .evaluation
= (struct lttng_evaluation
*) evaluation
,
4661 struct lttng_notification_channel_message msg_header
;
4662 const struct lttng_credentials
*trigger_creds
=
4663 lttng_trigger_get_credentials(trigger
);
4665 lttng_payload_init(&msg_payload
);
4667 msg_header
.type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION
;
4668 msg_header
.size
= 0;
4671 ret
= lttng_dynamic_buffer_append(&msg_payload
.buffer
, &msg_header
,
4672 sizeof(msg_header
));
4677 ret
= lttng_notification_serialize(¬ification
, &msg_payload
);
4679 ERR("Failed to serialize notification");
4684 /* Update payload size. */
4685 ((struct lttng_notification_channel_message
*) msg_payload
.buffer
.data
)
4686 ->size
= (uint32_t)(
4687 msg_payload
.buffer
.size
- sizeof(msg_header
));
4689 /* Update the payload number of fds. */
4691 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
4692 &msg_payload
, 0, -1);
4694 ((struct lttng_notification_channel_message
*)
4695 msg_payload
.buffer
.data
)->fds
= (uint32_t)
4696 lttng_payload_view_get_fd_handle_count(&pv
);
4699 pthread_mutex_lock(&client_list
->lock
);
4700 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4701 &client_list
->clients_list
, node
) {
4702 enum client_transmission_status transmission_status
;
4703 struct notification_client
*client
=
4704 client_list_element
->client
;
4707 pthread_mutex_lock(&client
->lock
);
4708 if (!client
->communication
.active
) {
4710 * Skip inactive client (protocol error or
4713 DBG("Skipping client at it is marked as inactive");
4717 if (lttng_trigger_is_hidden(trigger
) && !client
->is_sessiond
) {
4719 * Notifications resulting from an hidden trigger are
4720 * only sent to the session daemon.
4722 DBG("Skipping client as the trigger is hidden and the client is not the session daemon");
4726 if (source_object_creds
) {
4727 if (client
->uid
!= lttng_credentials_get_uid(source_object_creds
) &&
4728 client
->gid
!= lttng_credentials_get_gid(source_object_creds
) &&
4731 * Client is not allowed to monitor this
4734 DBG("Skipping client at it does not have the object permission to receive notification for this trigger");
4739 if (client
->uid
!= lttng_credentials_get_uid(trigger_creds
)) {
4740 DBG("Skipping client at it does not have the permission to receive notification for this trigger");
4744 DBG("Sending notification to client (fd = %i, %zu bytes)",
4745 client
->socket
, msg_payload
.buffer
.size
);
4747 if (client_has_outbound_data_left(client
)) {
4749 * Outgoing data is already buffered for this client;
4750 * drop the notification and enqueue a "dropped
4751 * notification" message if this is the first dropped
4752 * notification since the socket spilled-over to the
4755 ret
= client_notification_overflow(client
);
4762 ret
= lttng_payload_copy(&msg_payload
, &client
->communication
.outbound
.payload
);
4768 transmission_status
= client_flush_outgoing_queue(client
);
4769 pthread_mutex_unlock(&client
->lock
);
4770 ret
= client_report(client
, transmission_status
, user_data
);
4773 goto end_unlock_list
;
4779 pthread_mutex_unlock(&client
->lock
);
4782 goto end_unlock_list
;
4788 pthread_mutex_unlock(&client_list
->lock
);
4790 lttng_payload_reset(&msg_payload
);
4795 struct lttng_event_notifier_notification
*recv_one_event_notifier_notification(
4796 int notification_pipe_read_fd
, enum lttng_domain_type domain
)
4800 struct lttng_event_notifier_notification
*notification
= NULL
;
4801 char *capture_buffer
= NULL
;
4802 size_t capture_buffer_size
;
4803 void *reception_buffer
;
4804 size_t reception_size
;
4806 struct lttng_ust_abi_event_notifier_notification ust_notification
;
4807 struct lttng_kernel_abi_event_notifier_notification kernel_notification
;
4809 /* Init lttng_event_notifier_notification */
4811 case LTTNG_DOMAIN_UST
:
4812 reception_buffer
= (void *) &ust_notification
;
4813 reception_size
= sizeof(ust_notification
);
4815 case LTTNG_DOMAIN_KERNEL
:
4816 reception_buffer
= (void *) &kernel_notification
;
4817 reception_size
= sizeof(kernel_notification
);
4824 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4825 * ensuring that read/write of tracer notifications are atomic.
4827 ret
= lttng_read(notification_pipe_read_fd
, reception_buffer
,
4829 if (ret
!= reception_size
) {
4830 PERROR("Failed to read from event source notification pipe: fd = %d, size to read = %zu, ret = %d",
4831 notification_pipe_read_fd
, reception_size
, ret
);
4837 case LTTNG_DOMAIN_UST
:
4838 token
= ust_notification
.token
;
4839 capture_buffer_size
= ust_notification
.capture_buf_size
;
4841 case LTTNG_DOMAIN_KERNEL
:
4842 token
= kernel_notification
.token
;
4843 capture_buffer_size
= kernel_notification
.capture_buf_size
;
4849 if (capture_buffer_size
== 0) {
4850 capture_buffer
= NULL
;
4854 if (capture_buffer_size
> MAX_CAPTURE_SIZE
) {
4855 ERR("Event notifier has a capture payload size which exceeds the maximum allowed size: capture_payload_size = %zu bytes, max allowed size = %d bytes",
4856 capture_buffer_size
, MAX_CAPTURE_SIZE
);
4860 capture_buffer
= calloc
<char>(capture_buffer_size
);
4861 if (!capture_buffer
) {
4862 ERR("Failed to allocate capture buffer");
4866 /* Fetch additional payload (capture). */
4867 ret
= lttng_read(notification_pipe_read_fd
, capture_buffer
, capture_buffer_size
);
4868 if (ret
!= capture_buffer_size
) {
4869 ERR("Failed to read from event source pipe (fd = %i)",
4870 notification_pipe_read_fd
);
4875 notification
= lttng_event_notifier_notification_create(token
, domain
,
4876 capture_buffer
, capture_buffer_size
);
4877 if (notification
== NULL
) {
4882 * Ownership transfered to the lttng_event_notifier_notification object.
4884 capture_buffer
= NULL
;
4887 free(capture_buffer
);
4888 return notification
;
4892 int dispatch_one_event_notifier_notification(struct notification_thread_state
*state
,
4893 struct lttng_event_notifier_notification
*notification
)
4895 struct cds_lfht_node
*node
;
4896 struct cds_lfht_iter iter
;
4897 struct notification_trigger_tokens_ht_element
*element
;
4898 struct lttng_evaluation
*evaluation
= NULL
;
4899 enum action_executor_status executor_status
;
4900 struct notification_client_list
*client_list
= NULL
;
4902 unsigned int capture_count
= 0;
4904 /* Find triggers associated with this token. */
4906 cds_lfht_lookup(state
->trigger_tokens_ht
,
4907 hash_key_u64(¬ification
->tracer_token
, lttng_ht_seed
),
4908 match_trigger_token
, ¬ification
->tracer_token
, &iter
);
4909 node
= cds_lfht_iter_get_node(&iter
);
4910 if (caa_unlikely(!node
)) {
4912 * This is not an error, slow consumption of the tracer
4913 * notifications can lead to situations where a trigger is
4914 * removed but we still get tracer notifications matching a
4915 * trigger that no longer exists.
4921 element
= caa_container_of(node
,
4922 struct notification_trigger_tokens_ht_element
,
4925 if (lttng_condition_event_rule_matches_get_capture_descriptor_count(
4926 lttng_trigger_get_const_condition(element
->trigger
),
4927 &capture_count
) != LTTNG_CONDITION_STATUS_OK
) {
4928 ERR("Failed to get capture count");
4933 if (!notification
->capture_buffer
&& capture_count
!= 0) {
4934 ERR("Expected capture but capture buffer is null");
4939 evaluation
= lttng_evaluation_event_rule_matches_create(
4940 lttng::utils::container_of(lttng_trigger_get_const_condition(
4942 <tng_condition_event_rule_matches::parent
),
4943 notification
->capture_buffer
,
4944 notification
->capture_buf_size
, false);
4946 if (evaluation
== NULL
) {
4947 ERR("Failed to create event rule matches evaluation while creating and enqueuing action executor job");
4952 client_list
= get_client_list_from_condition(state
,
4953 lttng_trigger_get_const_condition(element
->trigger
));
4954 executor_status
= action_executor_enqueue_trigger(state
->executor
,
4955 element
->trigger
, evaluation
, NULL
, client_list
);
4956 switch (executor_status
) {
4957 case ACTION_EXECUTOR_STATUS_OK
:
4960 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4962 struct notification_client_list_element
*client_list_element
,
4966 * Not a fatal error; this is expected and simply means the
4967 * executor has too much work queued already.
4971 /* No clients subscribed to notifications for this trigger. */
4976 /* Warn clients that a notification (or more) was dropped. */
4977 pthread_mutex_lock(&client_list
->lock
);
4978 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4979 &client_list
->clients_list
, node
) {
4980 enum client_transmission_status transmission_status
;
4981 struct notification_client
*client
=
4982 client_list_element
->client
;
4984 pthread_mutex_lock(&client
->lock
);
4985 ret
= client_notification_overflow(client
);
4991 transmission_status
=
4992 client_flush_outgoing_queue(client
);
4993 ret
= client_handle_transmission_status(
4994 client
, transmission_status
, state
);
5000 pthread_mutex_unlock(&client
->lock
);
5006 pthread_mutex_unlock(&client_list
->lock
);
5009 case ACTION_EXECUTOR_STATUS_INVALID
:
5010 case ACTION_EXECUTOR_STATUS_ERROR
:
5011 /* Fatal error, shut down everything. */
5012 ERR("Fatal error encoutered while enqueuing action to the action executor");
5016 /* Unhandled error. */
5021 notification_client_list_put(client_list
);
5028 int handle_one_event_notifier_notification(
5029 struct notification_thread_state
*state
,
5030 int pipe
, enum lttng_domain_type domain
)
5033 struct lttng_event_notifier_notification
*notification
= NULL
;
5035 notification
= recv_one_event_notifier_notification(pipe
, domain
);
5036 if (notification
== NULL
) {
5037 /* Reception failed, don't consider it fatal. */
5038 ERR("Error receiving an event notifier notification from tracer: fd = %i, domain = %s",
5039 pipe
, lttng_domain_type_str(domain
));
5043 ret
= dispatch_one_event_notifier_notification(state
, notification
);
5045 ERR("Error dispatching an event notifier notification from tracer: fd = %i, domain = %s",
5046 pipe
, lttng_domain_type_str(domain
));
5051 lttng_event_notifier_notification_destroy(notification
);
5055 int handle_notification_thread_event_notification(struct notification_thread_state
*state
,
5056 int pipe
, enum lttng_domain_type domain
)
5058 return handle_one_event_notifier_notification(state
, pipe
, domain
);
5061 int handle_notification_thread_channel_sample(
5062 struct notification_thread_state
*state
, int pipe
,
5063 enum lttng_domain_type domain
)
5066 struct lttcomm_consumer_channel_monitor_msg sample_msg
;
5067 struct channel_info
*channel_info
= NULL
;
5068 struct cds_lfht_node
*node
;
5069 struct cds_lfht_iter iter
;
5070 struct lttng_channel_trigger_list
*channel_trigger_list
;
5071 struct lttng_session_trigger_list
*session_trigger_list
;
5072 struct lttng_trigger_list_element
*trigger_list_element
;
5073 bool previous_sample_available
= false;
5074 struct channel_state_sample channel_previous_sample
, channel_new_sample
;
5075 struct session_state_sample session_new_sample
;
5076 struct lttng_credentials channel_creds
= {};
5077 struct lttng_credentials session_creds
= {};
5078 struct session_info
*session
;
5081 * The monitoring pipe only holds messages smaller than PIPE_BUF,
5082 * ensuring that read/write of sampling messages are atomic.
5084 ret
= lttng_read(pipe
, &sample_msg
, sizeof(sample_msg
));
5085 if (ret
!= sizeof(sample_msg
)) {
5086 ERR("Failed to read from monitoring pipe (fd = %i)",
5093 channel_new_sample
.key
.key
= sample_msg
.key
;
5094 channel_new_sample
.key
.domain
= domain
;
5095 channel_new_sample
.highest_usage
= sample_msg
.highest
;
5096 channel_new_sample
.lowest_usage
= sample_msg
.lowest
;
5100 session
= get_session_info_by_id(state
, sample_msg
.session_id
);
5102 DBG("Received a sample for an unknown session from consumerd: session id = %" PRIu64
,
5103 sample_msg
.session_id
);
5107 session_new_sample
= session
->last_state_sample
;
5108 session_new_sample
.consumed_data_size
+= sample_msg
.consumed_since_last_sample
;
5110 .uid
= LTTNG_OPTIONAL_INIT_VALUE(session
->uid
),
5111 .gid
= LTTNG_OPTIONAL_INIT_VALUE(session
->gid
),
5114 session_trigger_list
= get_session_trigger_list(state
, session
->name
);
5115 LTTNG_ASSERT(session_trigger_list
);
5116 cds_list_for_each_entry(trigger_list_element
, &session_trigger_list
->list
,
5118 const struct lttng_condition
*condition
;
5119 struct lttng_trigger
*trigger
;
5120 struct notification_client_list
*client_list
= NULL
;
5121 struct lttng_evaluation
*evaluation
= NULL
;
5122 enum action_executor_status executor_status
;
5125 trigger
= trigger_list_element
->trigger
;
5126 condition
= lttng_trigger_get_const_condition(trigger
);
5127 LTTNG_ASSERT(condition
);
5129 ret
= evaluate_session_condition(
5130 condition
, session
, &session_new_sample
, &evaluation
);
5131 if (caa_unlikely(ret
)) {
5135 if (caa_likely(!evaluation
)) {
5140 * Ownership of `evaluation` transferred to the action executor
5141 * no matter the result. The callee acquires a reference to the
5142 * client list: we can release our own.
5144 client_list
= get_client_list_from_condition(state
, condition
);
5145 executor_status
= action_executor_enqueue_trigger(
5146 state
->executor
, trigger
, evaluation
,
5147 &session_creds
, client_list
);
5148 notification_client_list_put(client_list
);
5150 switch (executor_status
) {
5151 case ACTION_EXECUTOR_STATUS_OK
:
5153 case ACTION_EXECUTOR_STATUS_ERROR
:
5154 case ACTION_EXECUTOR_STATUS_INVALID
:
5156 * TODO Add trigger identification (name/id) when
5157 * it is added to the API.
5159 ERR("Fatal error occurred while enqueuing action associated with buffer-condition trigger");
5162 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
5164 * TODO Add trigger identification (name/id) when
5165 * it is added to the API.
5167 * Not a fatal error.
5169 WARN("No space left when enqueuing action associated with buffer-condition trigger");
5177 /* Retrieve the channel's informations */
5178 cds_lfht_lookup(state
->channels_ht
,
5179 hash_channel_key(&channel_new_sample
.key
),
5181 &channel_new_sample
.key
,
5183 node
= cds_lfht_iter_get_node(&iter
);
5184 if (caa_unlikely(!node
)) {
5186 * Not an error since the consumer can push a sample to the pipe
5187 * and the rest of the session daemon could notify us of the
5188 * channel's destruction before we get a chance to process that
5191 DBG("Received a sample for an unknown channel from consumerd, key = %" PRIu64
" in %s domain",
5192 channel_new_sample
.key
.key
,
5193 lttng_domain_type_str(domain
));
5197 channel_info
= caa_container_of(node
, struct channel_info
,
5199 DBG("Handling channel sample for channel %s (key = %" PRIu64
") in session %s (highest usage = %" PRIu64
", lowest usage = %" PRIu64
", consumed since last sample = %" PRIu64
")",
5201 channel_new_sample
.key
.key
,
5202 channel_info
->session_info
->name
,
5203 channel_new_sample
.highest_usage
,
5204 channel_new_sample
.lowest_usage
,
5205 sample_msg
.consumed_since_last_sample
);
5207 /* Retrieve the channel's last sample, if it exists, and update it. */
5208 cds_lfht_lookup(state
->channel_state_ht
,
5209 hash_channel_key(&channel_new_sample
.key
),
5210 match_channel_state_sample
,
5211 &channel_new_sample
.key
,
5213 node
= cds_lfht_iter_get_node(&iter
);
5214 if (caa_likely(node
)) {
5215 struct channel_state_sample
*stored_sample
;
5217 /* Update the sample stored. */
5218 stored_sample
= caa_container_of(node
,
5219 struct channel_state_sample
,
5220 channel_state_ht_node
);
5222 memcpy(&channel_previous_sample
, stored_sample
,
5223 sizeof(channel_previous_sample
));
5224 stored_sample
->highest_usage
= channel_new_sample
.highest_usage
;
5225 stored_sample
->lowest_usage
= channel_new_sample
.lowest_usage
;
5226 previous_sample_available
= true;
5229 * This is the channel's first sample, allocate space for and
5230 * store the new sample.
5232 struct channel_state_sample
*stored_sample
;
5234 stored_sample
= zmalloc
<channel_state_sample
>();
5235 if (!stored_sample
) {
5240 memcpy(stored_sample
, &channel_new_sample
, sizeof(*stored_sample
));
5241 cds_lfht_node_init(&stored_sample
->channel_state_ht_node
);
5242 cds_lfht_add(state
->channel_state_ht
,
5243 hash_channel_key(&stored_sample
->key
),
5244 &stored_sample
->channel_state_ht_node
);
5247 /* Find triggers associated with this channel. */
5248 cds_lfht_lookup(state
->channel_triggers_ht
,
5249 hash_channel_key(&channel_new_sample
.key
),
5250 match_channel_trigger_list
,
5251 &channel_new_sample
.key
,
5253 node
= cds_lfht_iter_get_node(&iter
);
5256 channel_creds
= (typeof(channel_creds
)) {
5257 .uid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->uid
),
5258 .gid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->gid
),
5261 channel_trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
5262 channel_triggers_ht_node
);
5263 cds_list_for_each_entry(trigger_list_element
, &channel_trigger_list
->list
,
5265 const struct lttng_condition
*condition
;
5266 struct lttng_trigger
*trigger
;
5267 struct notification_client_list
*client_list
= NULL
;
5268 struct lttng_evaluation
*evaluation
= NULL
;
5269 enum action_executor_status executor_status
;
5272 trigger
= trigger_list_element
->trigger
;
5273 condition
= lttng_trigger_get_const_condition(trigger
);
5274 LTTNG_ASSERT(condition
);
5276 ret
= evaluate_buffer_condition(condition
, &evaluation
, state
,
5277 previous_sample_available
? &channel_previous_sample
: NULL
,
5278 &channel_new_sample
,
5280 if (caa_unlikely(ret
)) {
5284 if (caa_likely(!evaluation
)) {
5289 * Ownership of `evaluation` transferred to the action executor
5290 * no matter the result. The callee acquires a reference to the
5291 * client list: we can release our own.
5293 client_list
= get_client_list_from_condition(state
, condition
);
5294 executor_status
= action_executor_enqueue_trigger(
5295 state
->executor
, trigger
, evaluation
,
5296 &channel_creds
, client_list
);
5297 notification_client_list_put(client_list
);
5299 switch (executor_status
) {
5300 case ACTION_EXECUTOR_STATUS_OK
:
5302 case ACTION_EXECUTOR_STATUS_ERROR
:
5303 case ACTION_EXECUTOR_STATUS_INVALID
:
5305 * TODO Add trigger identification (name/id) when
5306 * it is added to the API.
5308 ERR("Fatal error occurred while enqueuing action associated with buffer-condition trigger");
5311 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
5313 * TODO Add trigger identification (name/id) when
5314 * it is added to the API.
5316 * Not a fatal error.
5318 WARN("No space left when enqueuing action associated with buffer-condition trigger");
5327 session
->last_state_sample
= session_new_sample
;
5329 session_info_put(session
);