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.h"
12 #include <urcu/rculfhash.h>
14 #include <common/defaults.h>
15 #include <common/error.h>
16 #include <common/futex.h>
17 #include <common/unix.h>
18 #include <common/dynamic-buffer.h>
19 #include <common/hashtable/utils.h>
20 #include <common/sessiond-comm/sessiond-comm.h>
21 #include <common/macros.h>
22 #include <lttng/condition/condition.h>
23 #include <lttng/action/action-internal.h>
24 #include <lttng/action/list-internal.h>
25 #include <lttng/domain-internal.h>
26 #include <lttng/notification/notification-internal.h>
27 #include <lttng/condition/condition-internal.h>
28 #include <lttng/condition/buffer-usage-internal.h>
29 #include <lttng/condition/session-consumed-size-internal.h>
30 #include <lttng/condition/session-rotation-internal.h>
31 #include <lttng/condition/event-rule-matches-internal.h>
32 #include <lttng/domain-internal.h>
33 #include <lttng/notification/channel-internal.h>
34 #include <lttng/trigger/trigger-internal.h>
35 #include <lttng/event-rule/event-rule-internal.h>
42 #include "condition-internal.h"
43 #include "event-notifier-error-accounting.h"
44 #include "notification-thread.h"
45 #include "notification-thread-events.h"
46 #include "notification-thread-commands.h"
47 #include "lttng-sessiond.h"
50 #define CLIENT_POLL_MASK_IN (LPOLLIN | LPOLLERR | LPOLLHUP | LPOLLRDHUP)
51 #define CLIENT_POLL_MASK_IN_OUT (CLIENT_POLL_MASK_IN | LPOLLOUT)
53 /* The tracers currently limit the capture size to PIPE_BUF (4kb on linux). */
54 #define MAX_CAPTURE_SIZE (PIPE_BUF)
56 enum lttng_object_type
{
57 LTTNG_OBJECT_TYPE_UNKNOWN
,
58 LTTNG_OBJECT_TYPE_NONE
,
59 LTTNG_OBJECT_TYPE_CHANNEL
,
60 LTTNG_OBJECT_TYPE_SESSION
,
63 struct lttng_trigger_list_element
{
64 /* No ownership of the trigger object is assumed. */
65 struct lttng_trigger
*trigger
;
66 struct cds_list_head node
;
69 struct lttng_channel_trigger_list
{
70 struct channel_key channel_key
;
71 /* List of struct lttng_trigger_list_element. */
72 struct cds_list_head list
;
73 /* Node in the channel_triggers_ht */
74 struct cds_lfht_node channel_triggers_ht_node
;
75 /* call_rcu delayed reclaim. */
76 struct rcu_head rcu_node
;
80 * List of triggers applying to a given session.
83 * - lttng_session_trigger_list_create()
84 * - lttng_session_trigger_list_build()
85 * - lttng_session_trigger_list_destroy()
86 * - lttng_session_trigger_list_add()
88 struct lttng_session_trigger_list
{
90 * Not owned by this; points to the session_info structure's
93 const char *session_name
;
94 /* List of struct lttng_trigger_list_element. */
95 struct cds_list_head list
;
96 /* Node in the session_triggers_ht */
97 struct cds_lfht_node session_triggers_ht_node
;
99 * Weak reference to the notification system's session triggers
102 * The session trigger list structure structure is owned by
103 * the session's session_info.
105 * The session_info is kept alive the the channel_infos holding a
106 * reference to it (reference counting). When those channels are
107 * destroyed (at runtime or on teardown), the reference they hold
108 * to the session_info are released. On destruction of session_info,
109 * session_info_destroy() will remove the list of triggers applying
110 * to this session from the notification system's state.
112 * This implies that the session_triggers_ht must be destroyed
113 * after the channels.
115 struct cds_lfht
*session_triggers_ht
;
116 /* Used for delayed RCU reclaim. */
117 struct rcu_head rcu_node
;
120 struct lttng_trigger_ht_element
{
121 struct lttng_trigger
*trigger
;
122 struct cds_lfht_node node
;
123 struct cds_lfht_node node_by_name_uid
;
124 struct cds_list_head client_list_trigger_node
;
125 /* call_rcu delayed reclaim. */
126 struct rcu_head rcu_node
;
129 struct lttng_condition_list_element
{
130 struct lttng_condition
*condition
;
131 struct cds_list_head node
;
134 struct channel_state_sample
{
135 struct channel_key key
;
136 struct cds_lfht_node channel_state_ht_node
;
137 uint64_t highest_usage
;
138 uint64_t lowest_usage
;
139 uint64_t channel_total_consumed
;
140 /* call_rcu delayed reclaim. */
141 struct rcu_head rcu_node
;
144 static unsigned long hash_channel_key(struct channel_key
*key
);
145 static int evaluate_buffer_condition(const struct lttng_condition
*condition
,
146 struct lttng_evaluation
**evaluation
,
147 const struct notification_thread_state
*state
,
148 const struct channel_state_sample
*previous_sample
,
149 const struct channel_state_sample
*latest_sample
,
150 uint64_t previous_session_consumed_total
,
151 uint64_t latest_session_consumed_total
,
152 struct channel_info
*channel_info
);
154 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
155 const struct lttng_evaluation
*evaluation
,
156 struct notification_client_list
*client_list
,
157 struct notification_thread_state
*state
,
158 uid_t channel_uid
, gid_t channel_gid
);
161 /* session_info API */
163 void session_info_destroy(void *_data
);
165 void session_info_get(struct session_info
*session_info
);
167 void session_info_put(struct session_info
*session_info
);
169 struct session_info
*session_info_create(const char *name
,
170 uid_t uid
, gid_t gid
,
171 struct lttng_session_trigger_list
*trigger_list
,
172 struct cds_lfht
*sessions_ht
);
174 void session_info_add_channel(struct session_info
*session_info
,
175 struct channel_info
*channel_info
);
177 void session_info_remove_channel(struct session_info
*session_info
,
178 struct channel_info
*channel_info
);
180 /* lttng_session_trigger_list API */
182 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
183 const char *session_name
,
184 struct cds_lfht
*session_triggers_ht
);
186 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
187 const struct notification_thread_state
*state
,
188 const char *session_name
);
190 void lttng_session_trigger_list_destroy(
191 struct lttng_session_trigger_list
*list
);
193 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
194 struct lttng_trigger
*trigger
);
197 int client_handle_transmission_status(
198 struct notification_client
*client
,
199 enum client_transmission_status transmission_status
,
200 struct notification_thread_state
*state
);
203 int handle_one_event_notifier_notification(
204 struct notification_thread_state
*state
,
205 int pipe
, enum lttng_domain_type domain
);
208 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
);
211 int match_client_socket(struct cds_lfht_node
*node
, const void *key
)
213 /* This double-cast is intended to supress pointer-to-cast warning. */
214 const int socket
= (int) (intptr_t) key
;
215 const struct notification_client
*client
= caa_container_of(node
,
216 struct notification_client
, client_socket_ht_node
);
218 return client
->socket
== socket
;
222 int match_client_id(struct cds_lfht_node
*node
, const void *key
)
224 /* This double-cast is intended to supress pointer-to-cast warning. */
225 const notification_client_id id
= *((notification_client_id
*) key
);
226 const struct notification_client
*client
= caa_container_of(
227 node
, struct notification_client
, client_id_ht_node
);
229 return client
->id
== id
;
233 int match_channel_trigger_list(struct cds_lfht_node
*node
, const void *key
)
235 struct channel_key
*channel_key
= (struct channel_key
*) key
;
236 struct lttng_channel_trigger_list
*trigger_list
;
238 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
239 channel_triggers_ht_node
);
241 return !!((channel_key
->key
== trigger_list
->channel_key
.key
) &&
242 (channel_key
->domain
== trigger_list
->channel_key
.domain
));
246 int match_session_trigger_list(struct cds_lfht_node
*node
, const void *key
)
248 const char *session_name
= (const char *) key
;
249 struct lttng_session_trigger_list
*trigger_list
;
251 trigger_list
= caa_container_of(node
, struct lttng_session_trigger_list
,
252 session_triggers_ht_node
);
254 return !!(strcmp(trigger_list
->session_name
, session_name
) == 0);
258 int match_channel_state_sample(struct cds_lfht_node
*node
, const void *key
)
260 struct channel_key
*channel_key
= (struct channel_key
*) key
;
261 struct channel_state_sample
*sample
;
263 sample
= caa_container_of(node
, struct channel_state_sample
,
264 channel_state_ht_node
);
266 return !!((channel_key
->key
== sample
->key
.key
) &&
267 (channel_key
->domain
== sample
->key
.domain
));
271 int match_channel_info(struct cds_lfht_node
*node
, const void *key
)
273 struct channel_key
*channel_key
= (struct channel_key
*) key
;
274 struct channel_info
*channel_info
;
276 channel_info
= caa_container_of(node
, struct channel_info
,
279 return !!((channel_key
->key
== channel_info
->key
.key
) &&
280 (channel_key
->domain
== channel_info
->key
.domain
));
284 int match_trigger(struct cds_lfht_node
*node
, const void *key
)
286 struct lttng_trigger
*trigger_key
= (struct lttng_trigger
*) key
;
287 struct lttng_trigger_ht_element
*trigger_ht_element
;
289 trigger_ht_element
= caa_container_of(node
, struct lttng_trigger_ht_element
,
292 return !!lttng_trigger_is_equal(trigger_key
, trigger_ht_element
->trigger
);
296 int match_trigger_token(struct cds_lfht_node
*node
, const void *key
)
298 const uint64_t *_key
= key
;
299 struct notification_trigger_tokens_ht_element
*element
;
301 element
= caa_container_of(node
,
302 struct notification_trigger_tokens_ht_element
, node
);
303 return *_key
== element
->token
;
307 int match_client_list_condition(struct cds_lfht_node
*node
, const void *key
)
309 struct lttng_condition
*condition_key
= (struct lttng_condition
*) key
;
310 struct notification_client_list
*client_list
;
311 const struct lttng_condition
*condition
;
313 LTTNG_ASSERT(condition_key
);
315 client_list
= caa_container_of(node
, struct notification_client_list
,
316 notification_trigger_clients_ht_node
);
317 condition
= client_list
->condition
;
319 return !!lttng_condition_is_equal(condition_key
, condition
);
323 int match_session(struct cds_lfht_node
*node
, const void *key
)
325 const char *name
= key
;
326 struct session_info
*session_info
= caa_container_of(
327 node
, struct session_info
, sessions_ht_node
);
329 return !strcmp(session_info
->name
, name
);
333 const char *notification_command_type_str(
334 enum notification_thread_command_type type
)
337 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
338 return "REGISTER_TRIGGER";
339 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
340 return "UNREGISTER_TRIGGER";
341 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
342 return "ADD_CHANNEL";
343 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
344 return "REMOVE_CHANNEL";
345 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
346 return "SESSION_ROTATION_ONGOING";
347 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
348 return "SESSION_ROTATION_COMPLETED";
349 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
350 return "ADD_TRACER_EVENT_SOURCE";
351 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
352 return "REMOVE_TRACER_EVENT_SOURCE";
353 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
354 return "LIST_TRIGGERS";
355 case NOTIFICATION_COMMAND_TYPE_GET_TRIGGER
:
356 return "GET_TRIGGER";
357 case NOTIFICATION_COMMAND_TYPE_QUIT
:
359 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
360 return "CLIENT_COMMUNICATION_UPDATE";
367 * Match trigger based on name and credentials only.
368 * Name duplication is NOT allowed for the same uid.
371 int match_trigger_by_name_uid(struct cds_lfht_node
*node
,
375 const char *element_trigger_name
;
376 const char *key_name
;
377 enum lttng_trigger_status status
;
378 const struct lttng_credentials
*key_creds
;
379 const struct lttng_credentials
*node_creds
;
380 const struct lttng_trigger
*trigger_key
=
381 (const struct lttng_trigger
*) key
;
382 const struct lttng_trigger_ht_element
*trigger_ht_element
=
383 caa_container_of(node
,
384 struct lttng_trigger_ht_element
,
387 status
= lttng_trigger_get_name(trigger_ht_element
->trigger
,
388 &element_trigger_name
);
389 element_trigger_name
= status
== LTTNG_TRIGGER_STATUS_OK
?
390 element_trigger_name
: NULL
;
392 status
= lttng_trigger_get_name(trigger_key
, &key_name
);
393 key_name
= status
== LTTNG_TRIGGER_STATUS_OK
? key_name
: NULL
;
397 * Consider null names as not equal. This is to maintain backwards
398 * compatibility with pre-2.13 anonymous triggers. Multiples anonymous
399 * triggers are allowed for a given user.
401 if (!element_trigger_name
|| !key_name
) {
405 if (strcmp(element_trigger_name
, key_name
) != 0) {
409 /* Compare the owners' UIDs. */
410 key_creds
= lttng_trigger_get_credentials(trigger_key
);
411 node_creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
413 match
= lttng_credentials_is_equal_uid(key_creds
, node_creds
);
420 * Hash trigger based on name and credentials only.
423 unsigned long hash_trigger_by_name_uid(const struct lttng_trigger
*trigger
)
425 unsigned long hash
= 0;
426 const struct lttng_credentials
*trigger_creds
;
427 const char *trigger_name
;
428 enum lttng_trigger_status status
;
430 status
= lttng_trigger_get_name(trigger
, &trigger_name
);
431 if (status
== LTTNG_TRIGGER_STATUS_OK
) {
432 hash
= hash_key_str(trigger_name
, lttng_ht_seed
);
435 trigger_creds
= lttng_trigger_get_credentials(trigger
);
436 hash
^= hash_key_ulong((void *) (unsigned long) LTTNG_OPTIONAL_GET(trigger_creds
->uid
),
443 unsigned long hash_channel_key(struct channel_key
*key
)
445 unsigned long key_hash
= hash_key_u64(&key
->key
, lttng_ht_seed
);
446 unsigned long domain_hash
= hash_key_ulong(
447 (void *) (unsigned long) key
->domain
, lttng_ht_seed
);
449 return key_hash
^ domain_hash
;
453 unsigned long hash_client_socket(int socket
)
455 return hash_key_ulong((void *) (unsigned long) socket
, lttng_ht_seed
);
459 unsigned long hash_client_id(notification_client_id id
)
461 return hash_key_u64(&id
, lttng_ht_seed
);
465 * Get the type of object to which a given condition applies. Bindings let
466 * the notification system evaluate a trigger's condition when a given
467 * object's state is updated.
469 * For instance, a condition bound to a channel will be evaluated everytime
470 * the channel's state is changed by a channel monitoring sample.
473 enum lttng_object_type
get_condition_binding_object(
474 const struct lttng_condition
*condition
)
476 switch (lttng_condition_get_type(condition
)) {
477 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
478 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
479 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
480 return LTTNG_OBJECT_TYPE_CHANNEL
;
481 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
482 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
483 return LTTNG_OBJECT_TYPE_SESSION
;
484 case LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES
:
485 return LTTNG_OBJECT_TYPE_NONE
;
487 return LTTNG_OBJECT_TYPE_UNKNOWN
;
492 void free_channel_info_rcu(struct rcu_head
*node
)
494 free(caa_container_of(node
, struct channel_info
, rcu_node
));
498 void channel_info_destroy(struct channel_info
*channel_info
)
504 if (channel_info
->session_info
) {
505 session_info_remove_channel(channel_info
->session_info
,
507 session_info_put(channel_info
->session_info
);
509 if (channel_info
->name
) {
510 free(channel_info
->name
);
512 call_rcu(&channel_info
->rcu_node
, free_channel_info_rcu
);
516 void free_session_info_rcu(struct rcu_head
*node
)
518 free(caa_container_of(node
, struct session_info
, rcu_node
));
521 /* Don't call directly, use the ref-counting mechanism. */
523 void session_info_destroy(void *_data
)
525 struct session_info
*session_info
= _data
;
528 LTTNG_ASSERT(session_info
);
529 if (session_info
->channel_infos_ht
) {
530 ret
= cds_lfht_destroy(session_info
->channel_infos_ht
, NULL
);
532 ERR("Failed to destroy channel information hash table");
535 lttng_session_trigger_list_destroy(session_info
->trigger_list
);
538 cds_lfht_del(session_info
->sessions_ht
,
539 &session_info
->sessions_ht_node
);
541 free(session_info
->name
);
542 call_rcu(&session_info
->rcu_node
, free_session_info_rcu
);
546 void session_info_get(struct session_info
*session_info
)
551 lttng_ref_get(&session_info
->ref
);
555 void session_info_put(struct session_info
*session_info
)
560 lttng_ref_put(&session_info
->ref
);
564 struct session_info
*session_info_create(const char *name
, uid_t uid
, gid_t gid
,
565 struct lttng_session_trigger_list
*trigger_list
,
566 struct cds_lfht
*sessions_ht
)
568 struct session_info
*session_info
;
572 session_info
= zmalloc(sizeof(*session_info
));
576 lttng_ref_init(&session_info
->ref
, session_info_destroy
);
578 session_info
->channel_infos_ht
= cds_lfht_new(DEFAULT_HT_SIZE
,
579 1, 0, CDS_LFHT_AUTO_RESIZE
| CDS_LFHT_ACCOUNTING
, NULL
);
580 if (!session_info
->channel_infos_ht
) {
584 cds_lfht_node_init(&session_info
->sessions_ht_node
);
585 session_info
->name
= strdup(name
);
586 if (!session_info
->name
) {
589 session_info
->uid
= uid
;
590 session_info
->gid
= gid
;
591 session_info
->trigger_list
= trigger_list
;
592 session_info
->sessions_ht
= sessions_ht
;
596 session_info_put(session_info
);
601 void session_info_add_channel(struct session_info
*session_info
,
602 struct channel_info
*channel_info
)
605 cds_lfht_add(session_info
->channel_infos_ht
,
606 hash_channel_key(&channel_info
->key
),
607 &channel_info
->session_info_channels_ht_node
);
612 void session_info_remove_channel(struct session_info
*session_info
,
613 struct channel_info
*channel_info
)
616 cds_lfht_del(session_info
->channel_infos_ht
,
617 &channel_info
->session_info_channels_ht_node
);
622 struct channel_info
*channel_info_create(const char *channel_name
,
623 struct channel_key
*channel_key
, uint64_t channel_capacity
,
624 struct session_info
*session_info
)
626 struct channel_info
*channel_info
= zmalloc(sizeof(*channel_info
));
632 cds_lfht_node_init(&channel_info
->channels_ht_node
);
633 cds_lfht_node_init(&channel_info
->session_info_channels_ht_node
);
634 memcpy(&channel_info
->key
, channel_key
, sizeof(*channel_key
));
635 channel_info
->capacity
= channel_capacity
;
637 channel_info
->name
= strdup(channel_name
);
638 if (!channel_info
->name
) {
643 * Set the references between session and channel infos:
644 * - channel_info holds a strong reference to session_info
645 * - session_info holds a weak reference to channel_info
647 session_info_get(session_info
);
648 session_info_add_channel(session_info
, channel_info
);
649 channel_info
->session_info
= session_info
;
653 channel_info_destroy(channel_info
);
657 bool notification_client_list_get(struct notification_client_list
*list
)
659 return urcu_ref_get_unless_zero(&list
->ref
);
663 void free_notification_client_list_rcu(struct rcu_head
*node
)
665 free(caa_container_of(node
, struct notification_client_list
,
670 void notification_client_list_release(struct urcu_ref
*list_ref
)
672 struct notification_client_list
*list
=
673 container_of(list_ref
, typeof(*list
), ref
);
674 struct notification_client_list_element
*client_list_element
, *tmp
;
676 lttng_condition_put(list
->condition
);
678 if (list
->notification_trigger_clients_ht
) {
681 cds_lfht_del(list
->notification_trigger_clients_ht
,
682 &list
->notification_trigger_clients_ht_node
);
684 list
->notification_trigger_clients_ht
= NULL
;
686 cds_list_for_each_entry_safe(client_list_element
, tmp
,
687 &list
->clients_list
, node
) {
688 free(client_list_element
);
691 LTTNG_ASSERT(cds_list_empty(&list
->triggers_list
));
693 pthread_mutex_destroy(&list
->lock
);
694 call_rcu(&list
->rcu_node
, free_notification_client_list_rcu
);
698 bool condition_applies_to_client(const struct lttng_condition
*condition
,
699 struct notification_client
*client
)
701 bool applies
= false;
702 struct lttng_condition_list_element
*condition_list_element
;
704 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
,
706 applies
= lttng_condition_is_equal(
707 condition_list_element
->condition
,
718 struct notification_client_list
*notification_client_list_create(
719 struct notification_thread_state
*state
,
720 const struct lttng_condition
*condition
)
722 struct notification_client
*client
;
723 struct cds_lfht_iter iter
;
724 struct notification_client_list
*client_list
;
726 client_list
= zmalloc(sizeof(*client_list
));
728 PERROR("Failed to allocate notification client list");
732 pthread_mutex_init(&client_list
->lock
, NULL
);
734 * The trigger that owns the condition has the first reference to this
737 urcu_ref_init(&client_list
->ref
);
738 cds_lfht_node_init(&client_list
->notification_trigger_clients_ht_node
);
739 CDS_INIT_LIST_HEAD(&client_list
->clients_list
);
740 CDS_INIT_LIST_HEAD(&client_list
->triggers_list
);
743 * Create a copy of the condition so that it's independent of any
744 * trigger. The client list may outlive the trigger object (which owns
745 * the condition) that is used to create it.
747 client_list
->condition
= lttng_condition_copy(condition
);
749 /* Build a list of clients to which this new condition applies. */
750 cds_lfht_for_each_entry (state
->client_socket_ht
, &iter
, client
,
751 client_socket_ht_node
) {
752 struct notification_client_list_element
*client_list_element
;
754 if (!condition_applies_to_client(condition
, client
)) {
758 client_list_element
= zmalloc(sizeof(*client_list_element
));
759 if (!client_list_element
) {
760 goto error_put_client_list
;
763 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
764 client_list_element
->client
= client
;
765 cds_list_add(&client_list_element
->node
, &client_list
->clients_list
);
768 client_list
->notification_trigger_clients_ht
=
769 state
->notification_trigger_clients_ht
;
773 * Add the client list to the global list of client list.
775 cds_lfht_add_unique(state
->notification_trigger_clients_ht
,
776 lttng_condition_hash(client_list
->condition
),
777 match_client_list_condition
,
778 client_list
->condition
,
779 &client_list
->notification_trigger_clients_ht_node
);
783 error_put_client_list
:
784 notification_client_list_put(client_list
);
791 void notification_client_list_put(struct notification_client_list
*list
)
796 return urcu_ref_put(&list
->ref
, notification_client_list_release
);
799 /* Provides a reference to the returned list. */
801 struct notification_client_list
*get_client_list_from_condition(
802 struct notification_thread_state
*state
,
803 const struct lttng_condition
*condition
)
805 struct cds_lfht_node
*node
;
806 struct cds_lfht_iter iter
;
807 struct notification_client_list
*list
= NULL
;
810 cds_lfht_lookup(state
->notification_trigger_clients_ht
,
811 lttng_condition_hash(condition
),
812 match_client_list_condition
,
815 node
= cds_lfht_iter_get_node(&iter
);
817 list
= container_of(node
, struct notification_client_list
,
818 notification_trigger_clients_ht_node
);
819 list
= notification_client_list_get(list
) ? list
: NULL
;
827 int evaluate_channel_condition_for_client(
828 const struct lttng_condition
*condition
,
829 struct notification_thread_state
*state
,
830 struct lttng_evaluation
**evaluation
,
831 uid_t
*session_uid
, gid_t
*session_gid
)
834 struct cds_lfht_iter iter
;
835 struct cds_lfht_node
*node
;
836 struct channel_info
*channel_info
= NULL
;
837 struct channel_key
*channel_key
= NULL
;
838 struct channel_state_sample
*last_sample
= NULL
;
839 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
843 /* Find the channel associated with the condition. */
844 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
,
845 channel_trigger_list
, channel_triggers_ht_node
) {
846 struct lttng_trigger_list_element
*element
;
848 cds_list_for_each_entry(element
, &channel_trigger_list
->list
, node
) {
849 const struct lttng_condition
*current_condition
=
850 lttng_trigger_get_const_condition(
853 LTTNG_ASSERT(current_condition
);
854 if (!lttng_condition_is_equal(condition
,
855 current_condition
)) {
859 /* Found the trigger, save the channel key. */
860 channel_key
= &channel_trigger_list
->channel_key
;
864 /* The channel key was found stop iteration. */
870 /* No channel found; normal exit. */
871 DBG("No known channel associated with newly subscribed-to condition");
876 /* Fetch channel info for the matching channel. */
877 cds_lfht_lookup(state
->channels_ht
,
878 hash_channel_key(channel_key
),
882 node
= cds_lfht_iter_get_node(&iter
);
884 channel_info
= caa_container_of(node
, struct channel_info
,
887 /* Retrieve the channel's last sample, if it exists. */
888 cds_lfht_lookup(state
->channel_state_ht
,
889 hash_channel_key(channel_key
),
890 match_channel_state_sample
,
893 node
= cds_lfht_iter_get_node(&iter
);
895 last_sample
= caa_container_of(node
,
896 struct channel_state_sample
,
897 channel_state_ht_node
);
899 /* Nothing to evaluate, no sample was ever taken. Normal exit */
900 DBG("No channel sample associated with newly subscribed-to condition");
905 ret
= evaluate_buffer_condition(condition
, evaluation
, state
,
907 0, channel_info
->session_info
->consumed_data_size
,
910 WARN("Fatal error occurred while evaluating a newly subscribed-to condition");
914 *session_uid
= channel_info
->session_info
->uid
;
915 *session_gid
= channel_info
->session_info
->gid
;
922 const char *get_condition_session_name(const struct lttng_condition
*condition
)
924 const char *session_name
= NULL
;
925 enum lttng_condition_status status
;
927 switch (lttng_condition_get_type(condition
)) {
928 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
929 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
930 status
= lttng_condition_buffer_usage_get_session_name(
931 condition
, &session_name
);
933 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
934 status
= lttng_condition_session_consumed_size_get_session_name(
935 condition
, &session_name
);
937 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
938 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
939 status
= lttng_condition_session_rotation_get_session_name(
940 condition
, &session_name
);
945 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
946 ERR("Failed to retrieve session rotation condition's session name");
954 int evaluate_session_condition_for_client(
955 const struct lttng_condition
*condition
,
956 struct notification_thread_state
*state
,
957 struct lttng_evaluation
**evaluation
,
958 uid_t
*session_uid
, gid_t
*session_gid
)
961 struct cds_lfht_iter iter
;
962 struct cds_lfht_node
*node
;
963 const char *session_name
;
964 struct session_info
*session_info
= NULL
;
967 session_name
= get_condition_session_name(condition
);
969 /* Find the session associated with the trigger. */
970 cds_lfht_lookup(state
->sessions_ht
,
971 hash_key_str(session_name
, lttng_ht_seed
),
975 node
= cds_lfht_iter_get_node(&iter
);
977 DBG("No known session matching name \"%s\"",
983 session_info
= caa_container_of(node
, struct session_info
,
985 session_info_get(session_info
);
988 * Evaluation is performed in-line here since only one type of
989 * session-bound condition is handled for the moment.
991 switch (lttng_condition_get_type(condition
)) {
992 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
993 if (!session_info
->rotation
.ongoing
) {
995 goto end_session_put
;
998 *evaluation
= lttng_evaluation_session_rotation_ongoing_create(
999 session_info
->rotation
.id
);
1002 ERR("Failed to create session rotation ongoing evaluation for session \"%s\"",
1003 session_info
->name
);
1005 goto end_session_put
;
1011 goto end_session_put
;
1014 *session_uid
= session_info
->uid
;
1015 *session_gid
= session_info
->gid
;
1018 session_info_put(session_info
);
1025 int evaluate_condition_for_client(const struct lttng_trigger
*trigger
,
1026 const struct lttng_condition
*condition
,
1027 struct notification_client
*client
,
1028 struct notification_thread_state
*state
)
1031 struct lttng_evaluation
*evaluation
= NULL
;
1032 struct notification_client_list client_list
= {
1033 .lock
= PTHREAD_MUTEX_INITIALIZER
,
1035 struct notification_client_list_element client_list_element
= { 0 };
1036 uid_t object_uid
= 0;
1037 gid_t object_gid
= 0;
1039 LTTNG_ASSERT(trigger
);
1040 LTTNG_ASSERT(condition
);
1041 LTTNG_ASSERT(client
);
1042 LTTNG_ASSERT(state
);
1044 switch (get_condition_binding_object(condition
)) {
1045 case LTTNG_OBJECT_TYPE_SESSION
:
1046 ret
= evaluate_session_condition_for_client(condition
, state
,
1047 &evaluation
, &object_uid
, &object_gid
);
1049 case LTTNG_OBJECT_TYPE_CHANNEL
:
1050 ret
= evaluate_channel_condition_for_client(condition
, state
,
1051 &evaluation
, &object_uid
, &object_gid
);
1053 case LTTNG_OBJECT_TYPE_NONE
:
1054 DBG("Newly subscribed-to condition not bound to object, nothing to evaluate");
1057 case LTTNG_OBJECT_TYPE_UNKNOWN
:
1067 /* Evaluation yielded nothing. Normal exit. */
1068 DBG("Newly subscribed-to condition evaluated to false, nothing to report to client");
1074 * Create a temporary client list with the client currently
1077 cds_lfht_node_init(&client_list
.notification_trigger_clients_ht_node
);
1078 CDS_INIT_LIST_HEAD(&client_list
.clients_list
);
1080 CDS_INIT_LIST_HEAD(&client_list_element
.node
);
1081 client_list_element
.client
= client
;
1082 cds_list_add(&client_list_element
.node
, &client_list
.clients_list
);
1084 /* Send evaluation result to the newly-subscribed client. */
1085 DBG("Newly subscribed-to condition evaluated to true, notifying client");
1086 ret
= send_evaluation_to_clients(trigger
, evaluation
, &client_list
,
1087 state
, object_uid
, object_gid
);
1094 int notification_thread_client_subscribe(struct notification_client
*client
,
1095 struct lttng_condition
*condition
,
1096 struct notification_thread_state
*state
,
1097 enum lttng_notification_channel_status
*_status
)
1100 struct notification_client_list
*client_list
= NULL
;
1101 struct lttng_condition_list_element
*condition_list_element
= NULL
;
1102 struct notification_client_list_element
*client_list_element
= NULL
;
1103 struct lttng_trigger_ht_element
*trigger_ht_element
;
1104 enum lttng_notification_channel_status status
=
1105 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1108 * Ensure that the client has not already subscribed to this condition
1111 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
, node
) {
1112 if (lttng_condition_is_equal(condition_list_element
->condition
,
1114 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_ALREADY_SUBSCRIBED
;
1119 condition_list_element
= zmalloc(sizeof(*condition_list_element
));
1120 if (!condition_list_element
) {
1124 client_list_element
= zmalloc(sizeof(*client_list_element
));
1125 if (!client_list_element
) {
1131 * Add the newly-subscribed condition to the client's subscription list.
1133 CDS_INIT_LIST_HEAD(&condition_list_element
->node
);
1134 condition_list_element
->condition
= condition
;
1136 cds_list_add(&condition_list_element
->node
, &client
->condition_list
);
1138 client_list
= get_client_list_from_condition(
1139 state
, condition_list_element
->condition
);
1142 * No notification-emiting trigger registered with this
1143 * condition. We don't evaluate the condition right away
1144 * since this trigger is not registered yet.
1146 free(client_list_element
);
1151 * The condition to which the client just subscribed is evaluated
1152 * at this point so that conditions that are already TRUE result
1153 * in a notification being sent out.
1155 * Note the iteration on all triggers which share an identical
1156 * `condition` than the one to which the client is registering. This is
1157 * done to ensure that the client receives a distinct notification for
1158 * all triggers that have a `notify` action that have this condition.
1160 pthread_mutex_lock(&client_list
->lock
);
1161 cds_list_for_each_entry(trigger_ht_element
,
1162 &client_list
->triggers_list
, client_list_trigger_node
) {
1163 if (evaluate_condition_for_client(trigger_ht_element
->trigger
, condition_list_element
->condition
,
1165 WARN("Evaluation of a condition on client subscription failed, aborting.");
1167 free(client_list_element
);
1168 pthread_mutex_unlock(&client_list
->lock
);
1172 pthread_mutex_unlock(&client_list
->lock
);
1175 * Add the client to the list of clients interested in a given trigger
1176 * if a "notification" trigger with a corresponding condition was
1179 client_list_element
->client
= client
;
1180 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
1182 pthread_mutex_lock(&client_list
->lock
);
1183 cds_list_add(&client_list_element
->node
, &client_list
->clients_list
);
1184 pthread_mutex_unlock(&client_list
->lock
);
1190 notification_client_list_put(client_list
);
1192 lttng_condition_destroy(condition
);
1195 free(condition_list_element
);
1196 free(client_list_element
);
1197 lttng_condition_destroy(condition
);
1202 int notification_thread_client_unsubscribe(
1203 struct notification_client
*client
,
1204 struct lttng_condition
*condition
,
1205 struct notification_thread_state
*state
,
1206 enum lttng_notification_channel_status
*_status
)
1208 struct notification_client_list
*client_list
;
1209 struct lttng_condition_list_element
*condition_list_element
,
1211 struct notification_client_list_element
*client_list_element
,
1213 bool condition_found
= false;
1214 enum lttng_notification_channel_status status
=
1215 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1217 /* Remove the condition from the client's condition list. */
1218 cds_list_for_each_entry_safe(condition_list_element
, condition_tmp
,
1219 &client
->condition_list
, node
) {
1220 if (!lttng_condition_is_equal(condition_list_element
->condition
,
1225 cds_list_del(&condition_list_element
->node
);
1227 * The caller may be iterating on the client's conditions to
1228 * tear down a client's connection. In this case, the condition
1229 * will be destroyed at the end.
1231 if (condition
!= condition_list_element
->condition
) {
1232 lttng_condition_destroy(
1233 condition_list_element
->condition
);
1235 free(condition_list_element
);
1236 condition_found
= true;
1240 if (!condition_found
) {
1241 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNKNOWN_CONDITION
;
1246 * Remove the client from the list of clients interested the trigger
1247 * matching the condition.
1249 client_list
= get_client_list_from_condition(state
, condition
);
1254 pthread_mutex_lock(&client_list
->lock
);
1255 cds_list_for_each_entry_safe(client_list_element
, client_tmp
,
1256 &client_list
->clients_list
, node
) {
1257 if (client_list_element
->client
->id
!= client
->id
) {
1260 cds_list_del(&client_list_element
->node
);
1261 free(client_list_element
);
1264 pthread_mutex_unlock(&client_list
->lock
);
1265 notification_client_list_put(client_list
);
1268 lttng_condition_destroy(condition
);
1276 void free_notification_client_rcu(struct rcu_head
*node
)
1278 free(caa_container_of(node
, struct notification_client
, rcu_node
));
1282 void notification_client_destroy(struct notification_client
*client
,
1283 struct notification_thread_state
*state
)
1290 * The client object is not reachable by other threads, no need to lock
1293 if (client
->socket
>= 0) {
1294 (void) lttcomm_close_unix_sock(client
->socket
);
1295 client
->socket
= -1;
1297 client
->communication
.active
= false;
1298 lttng_payload_reset(&client
->communication
.inbound
.payload
);
1299 lttng_payload_reset(&client
->communication
.outbound
.payload
);
1300 pthread_mutex_destroy(&client
->lock
);
1301 call_rcu(&client
->rcu_node
, free_notification_client_rcu
);
1305 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1309 struct notification_client
*get_client_from_socket(int socket
,
1310 struct notification_thread_state
*state
)
1312 struct cds_lfht_iter iter
;
1313 struct cds_lfht_node
*node
;
1314 struct notification_client
*client
= NULL
;
1316 cds_lfht_lookup(state
->client_socket_ht
,
1317 hash_client_socket(socket
),
1318 match_client_socket
,
1319 (void *) (unsigned long) socket
,
1321 node
= cds_lfht_iter_get_node(&iter
);
1326 client
= caa_container_of(node
, struct notification_client
,
1327 client_socket_ht_node
);
1333 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1337 struct notification_client
*get_client_from_id(notification_client_id id
,
1338 struct notification_thread_state
*state
)
1340 struct cds_lfht_iter iter
;
1341 struct cds_lfht_node
*node
;
1342 struct notification_client
*client
= NULL
;
1344 cds_lfht_lookup(state
->client_id_ht
,
1349 node
= cds_lfht_iter_get_node(&iter
);
1354 client
= caa_container_of(node
, struct notification_client
,
1361 bool buffer_usage_condition_applies_to_channel(
1362 const struct lttng_condition
*condition
,
1363 const struct channel_info
*channel_info
)
1365 enum lttng_condition_status status
;
1366 enum lttng_domain_type condition_domain
;
1367 const char *condition_session_name
= NULL
;
1368 const char *condition_channel_name
= NULL
;
1370 status
= lttng_condition_buffer_usage_get_domain_type(condition
,
1372 LTTNG_ASSERT(status
== LTTNG_CONDITION_STATUS_OK
);
1373 if (channel_info
->key
.domain
!= condition_domain
) {
1377 status
= lttng_condition_buffer_usage_get_session_name(
1378 condition
, &condition_session_name
);
1379 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1381 status
= lttng_condition_buffer_usage_get_channel_name(
1382 condition
, &condition_channel_name
);
1383 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_channel_name
);
1385 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1388 if (strcmp(channel_info
->name
, condition_channel_name
)) {
1398 bool session_consumed_size_condition_applies_to_channel(
1399 const struct lttng_condition
*condition
,
1400 const struct channel_info
*channel_info
)
1402 enum lttng_condition_status status
;
1403 const char *condition_session_name
= NULL
;
1405 status
= lttng_condition_session_consumed_size_get_session_name(
1406 condition
, &condition_session_name
);
1407 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1409 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1419 bool trigger_applies_to_channel(const struct lttng_trigger
*trigger
,
1420 const struct channel_info
*channel_info
)
1422 const struct lttng_condition
*condition
;
1423 bool trigger_applies
;
1425 condition
= lttng_trigger_get_const_condition(trigger
);
1430 switch (lttng_condition_get_type(condition
)) {
1431 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
1432 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
1433 trigger_applies
= buffer_usage_condition_applies_to_channel(
1434 condition
, channel_info
);
1436 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
1437 trigger_applies
= session_consumed_size_condition_applies_to_channel(
1438 condition
, channel_info
);
1444 return trigger_applies
;
1449 /* Must be called with RCU read lock held. */
1451 struct lttng_session_trigger_list
*get_session_trigger_list(
1452 struct notification_thread_state
*state
,
1453 const char *session_name
)
1455 struct lttng_session_trigger_list
*list
= NULL
;
1456 struct cds_lfht_node
*node
;
1457 struct cds_lfht_iter iter
;
1459 cds_lfht_lookup(state
->session_triggers_ht
,
1460 hash_key_str(session_name
, lttng_ht_seed
),
1461 match_session_trigger_list
,
1464 node
= cds_lfht_iter_get_node(&iter
);
1467 * Not an error, the list of triggers applying to that session
1468 * will be initialized when the session is created.
1470 DBG("No trigger list found for session \"%s\" as it is not yet known to the notification system",
1475 list
= caa_container_of(node
,
1476 struct lttng_session_trigger_list
,
1477 session_triggers_ht_node
);
1483 * Allocate an empty lttng_session_trigger_list for the session named
1486 * No ownership of 'session_name' is assumed by the session trigger list.
1487 * It is the caller's responsability to ensure the session name is alive
1488 * for as long as this list is.
1491 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
1492 const char *session_name
,
1493 struct cds_lfht
*session_triggers_ht
)
1495 struct lttng_session_trigger_list
*list
;
1497 list
= zmalloc(sizeof(*list
));
1501 list
->session_name
= session_name
;
1502 CDS_INIT_LIST_HEAD(&list
->list
);
1503 cds_lfht_node_init(&list
->session_triggers_ht_node
);
1504 list
->session_triggers_ht
= session_triggers_ht
;
1507 /* Publish the list through the session_triggers_ht. */
1508 cds_lfht_add(session_triggers_ht
,
1509 hash_key_str(session_name
, lttng_ht_seed
),
1510 &list
->session_triggers_ht_node
);
1517 void free_session_trigger_list_rcu(struct rcu_head
*node
)
1519 free(caa_container_of(node
, struct lttng_session_trigger_list
,
1524 void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list
*list
)
1526 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1528 /* Empty the list element by element, and then free the list itself. */
1529 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1530 &list
->list
, node
) {
1531 cds_list_del(&trigger_list_element
->node
);
1532 free(trigger_list_element
);
1535 /* Unpublish the list from the session_triggers_ht. */
1536 cds_lfht_del(list
->session_triggers_ht
,
1537 &list
->session_triggers_ht_node
);
1539 call_rcu(&list
->rcu_node
, free_session_trigger_list_rcu
);
1543 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
1544 struct lttng_trigger
*trigger
)
1547 struct lttng_trigger_list_element
*new_element
=
1548 zmalloc(sizeof(*new_element
));
1554 CDS_INIT_LIST_HEAD(&new_element
->node
);
1555 new_element
->trigger
= trigger
;
1556 cds_list_add(&new_element
->node
, &list
->list
);
1562 bool trigger_applies_to_session(const struct lttng_trigger
*trigger
,
1563 const char *session_name
)
1565 bool applies
= false;
1566 const struct lttng_condition
*condition
;
1568 condition
= lttng_trigger_get_const_condition(trigger
);
1569 switch (lttng_condition_get_type(condition
)) {
1570 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1571 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1573 enum lttng_condition_status condition_status
;
1574 const char *condition_session_name
;
1576 condition_status
= lttng_condition_session_rotation_get_session_name(
1577 condition
, &condition_session_name
);
1578 if (condition_status
!= LTTNG_CONDITION_STATUS_OK
) {
1579 ERR("Failed to retrieve session rotation condition's session name");
1583 LTTNG_ASSERT(condition_session_name
);
1584 applies
= !strcmp(condition_session_name
, session_name
);
1595 * Allocate and initialize an lttng_session_trigger_list which contains
1596 * all triggers that apply to the session named 'session_name'.
1598 * No ownership of 'session_name' is assumed by the session trigger list.
1599 * It is the caller's responsability to ensure the session name is alive
1600 * for as long as this list is.
1603 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
1604 const struct notification_thread_state
*state
,
1605 const char *session_name
)
1607 int trigger_count
= 0;
1608 struct lttng_session_trigger_list
*session_trigger_list
= NULL
;
1609 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1610 struct cds_lfht_iter iter
;
1612 session_trigger_list
= lttng_session_trigger_list_create(session_name
,
1613 state
->session_triggers_ht
);
1615 /* Add all triggers applying to the session named 'session_name'. */
1616 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1620 if (!trigger_applies_to_session(trigger_ht_element
->trigger
,
1625 ret
= lttng_session_trigger_list_add(session_trigger_list
,
1626 trigger_ht_element
->trigger
);
1634 DBG("Found %i triggers that apply to newly created session",
1636 return session_trigger_list
;
1638 lttng_session_trigger_list_destroy(session_trigger_list
);
1643 struct session_info
*find_or_create_session_info(
1644 struct notification_thread_state
*state
,
1645 const char *name
, uid_t uid
, gid_t gid
)
1647 struct session_info
*session
= NULL
;
1648 struct cds_lfht_node
*node
;
1649 struct cds_lfht_iter iter
;
1650 struct lttng_session_trigger_list
*trigger_list
;
1653 cds_lfht_lookup(state
->sessions_ht
,
1654 hash_key_str(name
, lttng_ht_seed
),
1658 node
= cds_lfht_iter_get_node(&iter
);
1660 DBG("Found session info of session \"%s\" (uid = %i, gid = %i)",
1662 session
= caa_container_of(node
, struct session_info
,
1664 LTTNG_ASSERT(session
->uid
== uid
);
1665 LTTNG_ASSERT(session
->gid
== gid
);
1666 session_info_get(session
);
1670 trigger_list
= lttng_session_trigger_list_build(state
, name
);
1671 if (!trigger_list
) {
1675 session
= session_info_create(name
, uid
, gid
, trigger_list
,
1676 state
->sessions_ht
);
1678 ERR("Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
1680 lttng_session_trigger_list_destroy(trigger_list
);
1683 trigger_list
= NULL
;
1685 cds_lfht_add(state
->sessions_ht
, hash_key_str(name
, lttng_ht_seed
),
1686 &session
->sessions_ht_node
);
1692 session_info_put(session
);
1697 int handle_notification_thread_command_add_channel(
1698 struct notification_thread_state
*state
,
1699 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1700 const char *channel_name
, enum lttng_domain_type channel_domain
,
1701 uint64_t channel_key_int
, uint64_t channel_capacity
,
1702 enum lttng_error_code
*cmd_result
)
1704 struct cds_list_head trigger_list
;
1705 struct channel_info
*new_channel_info
= NULL
;
1706 struct channel_key channel_key
= {
1707 .key
= channel_key_int
,
1708 .domain
= channel_domain
,
1710 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
1711 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1712 int trigger_count
= 0;
1713 struct cds_lfht_iter iter
;
1714 struct session_info
*session_info
= NULL
;
1716 DBG("Adding channel %s from session %s, channel key = %" PRIu64
" in %s domain",
1717 channel_name
, session_name
, channel_key_int
,
1718 lttng_domain_type_str(channel_domain
));
1720 CDS_INIT_LIST_HEAD(&trigger_list
);
1722 session_info
= find_or_create_session_info(state
, session_name
,
1723 session_uid
, session_gid
);
1724 if (!session_info
) {
1725 /* Allocation error or an internal error occurred. */
1729 new_channel_info
= channel_info_create(channel_name
, &channel_key
,
1730 channel_capacity
, session_info
);
1731 if (!new_channel_info
) {
1736 /* Build a list of all triggers applying to the new channel. */
1737 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1739 struct lttng_trigger_list_element
*new_element
;
1741 if (!trigger_applies_to_channel(trigger_ht_element
->trigger
,
1742 new_channel_info
)) {
1746 new_element
= zmalloc(sizeof(*new_element
));
1751 CDS_INIT_LIST_HEAD(&new_element
->node
);
1752 new_element
->trigger
= trigger_ht_element
->trigger
;
1753 cds_list_add(&new_element
->node
, &trigger_list
);
1758 DBG("Found %i triggers that apply to newly added channel",
1760 channel_trigger_list
= zmalloc(sizeof(*channel_trigger_list
));
1761 if (!channel_trigger_list
) {
1764 channel_trigger_list
->channel_key
= new_channel_info
->key
;
1765 CDS_INIT_LIST_HEAD(&channel_trigger_list
->list
);
1766 cds_lfht_node_init(&channel_trigger_list
->channel_triggers_ht_node
);
1767 cds_list_splice(&trigger_list
, &channel_trigger_list
->list
);
1770 /* Add channel to the channel_ht which owns the channel_infos. */
1771 cds_lfht_add(state
->channels_ht
,
1772 hash_channel_key(&new_channel_info
->key
),
1773 &new_channel_info
->channels_ht_node
);
1775 * Add the list of triggers associated with this channel to the
1776 * channel_triggers_ht.
1778 cds_lfht_add(state
->channel_triggers_ht
,
1779 hash_channel_key(&new_channel_info
->key
),
1780 &channel_trigger_list
->channel_triggers_ht_node
);
1782 session_info_put(session_info
);
1783 *cmd_result
= LTTNG_OK
;
1786 channel_info_destroy(new_channel_info
);
1787 session_info_put(session_info
);
1792 void free_channel_trigger_list_rcu(struct rcu_head
*node
)
1794 free(caa_container_of(node
, struct lttng_channel_trigger_list
,
1799 void free_channel_state_sample_rcu(struct rcu_head
*node
)
1801 free(caa_container_of(node
, struct channel_state_sample
,
1806 int handle_notification_thread_command_remove_channel(
1807 struct notification_thread_state
*state
,
1808 uint64_t channel_key
, enum lttng_domain_type domain
,
1809 enum lttng_error_code
*cmd_result
)
1811 struct cds_lfht_node
*node
;
1812 struct cds_lfht_iter iter
;
1813 struct lttng_channel_trigger_list
*trigger_list
;
1814 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1815 struct channel_key key
= { .key
= channel_key
, .domain
= domain
};
1816 struct channel_info
*channel_info
;
1818 DBG("Removing channel key = %" PRIu64
" in %s domain",
1819 channel_key
, lttng_domain_type_str(domain
));
1823 cds_lfht_lookup(state
->channel_triggers_ht
,
1824 hash_channel_key(&key
),
1825 match_channel_trigger_list
,
1828 node
= cds_lfht_iter_get_node(&iter
);
1830 * There is a severe internal error if we are being asked to remove a
1831 * channel that doesn't exist.
1834 ERR("Channel being removed is unknown to the notification thread");
1838 /* Free the list of triggers associated with this channel. */
1839 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
1840 channel_triggers_ht_node
);
1841 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1842 &trigger_list
->list
, node
) {
1843 cds_list_del(&trigger_list_element
->node
);
1844 free(trigger_list_element
);
1846 cds_lfht_del(state
->channel_triggers_ht
, node
);
1847 call_rcu(&trigger_list
->rcu_node
, free_channel_trigger_list_rcu
);
1849 /* Free sampled channel state. */
1850 cds_lfht_lookup(state
->channel_state_ht
,
1851 hash_channel_key(&key
),
1852 match_channel_state_sample
,
1855 node
= cds_lfht_iter_get_node(&iter
);
1857 * This is expected to be NULL if the channel is destroyed before we
1858 * received a sample.
1861 struct channel_state_sample
*sample
= caa_container_of(node
,
1862 struct channel_state_sample
,
1863 channel_state_ht_node
);
1865 cds_lfht_del(state
->channel_state_ht
, node
);
1866 call_rcu(&sample
->rcu_node
, free_channel_state_sample_rcu
);
1869 /* Remove the channel from the channels_ht and free it. */
1870 cds_lfht_lookup(state
->channels_ht
,
1871 hash_channel_key(&key
),
1875 node
= cds_lfht_iter_get_node(&iter
);
1877 channel_info
= caa_container_of(node
, struct channel_info
,
1879 cds_lfht_del(state
->channels_ht
, node
);
1880 channel_info_destroy(channel_info
);
1883 *cmd_result
= LTTNG_OK
;
1888 int handle_notification_thread_command_session_rotation(
1889 struct notification_thread_state
*state
,
1890 enum notification_thread_command_type cmd_type
,
1891 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1892 uint64_t trace_archive_chunk_id
,
1893 struct lttng_trace_archive_location
*location
,
1894 enum lttng_error_code
*_cmd_result
)
1897 enum lttng_error_code cmd_result
= LTTNG_OK
;
1898 struct lttng_session_trigger_list
*trigger_list
;
1899 struct lttng_trigger_list_element
*trigger_list_element
;
1900 struct session_info
*session_info
;
1901 const struct lttng_credentials session_creds
= {
1902 .uid
= LTTNG_OPTIONAL_INIT_VALUE(session_uid
),
1903 .gid
= LTTNG_OPTIONAL_INIT_VALUE(session_gid
),
1908 session_info
= find_or_create_session_info(state
, session_name
,
1909 session_uid
, session_gid
);
1910 if (!session_info
) {
1911 /* Allocation error or an internal error occurred. */
1913 cmd_result
= LTTNG_ERR_NOMEM
;
1917 session_info
->rotation
.ongoing
=
1918 cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
;
1919 session_info
->rotation
.id
= trace_archive_chunk_id
;
1920 trigger_list
= get_session_trigger_list(state
, session_name
);
1921 if (!trigger_list
) {
1922 DBG("No triggers applying to session \"%s\" found",
1927 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
1929 const struct lttng_condition
*condition
;
1930 struct lttng_trigger
*trigger
;
1931 struct notification_client_list
*client_list
;
1932 struct lttng_evaluation
*evaluation
= NULL
;
1933 enum lttng_condition_type condition_type
;
1934 enum action_executor_status executor_status
;
1936 trigger
= trigger_list_element
->trigger
;
1937 condition
= lttng_trigger_get_const_condition(trigger
);
1938 LTTNG_ASSERT(condition
);
1939 condition_type
= lttng_condition_get_type(condition
);
1941 if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
&&
1942 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1944 } else if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
&&
1945 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
) {
1949 client_list
= get_client_list_from_condition(state
, condition
);
1950 if (cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1951 evaluation
= lttng_evaluation_session_rotation_ongoing_create(
1952 trace_archive_chunk_id
);
1954 evaluation
= lttng_evaluation_session_rotation_completed_create(
1955 trace_archive_chunk_id
, location
);
1959 /* Internal error */
1961 cmd_result
= LTTNG_ERR_UNK
;
1966 * Ownership of `evaluation` transferred to the action executor
1967 * no matter the result.
1969 executor_status
= action_executor_enqueue_trigger(
1970 state
->executor
, trigger
, evaluation
,
1971 &session_creds
, client_list
);
1973 switch (executor_status
) {
1974 case ACTION_EXECUTOR_STATUS_OK
:
1976 case ACTION_EXECUTOR_STATUS_ERROR
:
1977 case ACTION_EXECUTOR_STATUS_INVALID
:
1979 * TODO Add trigger identification (name/id) when
1980 * it is added to the API.
1982 ERR("Fatal error occurred while enqueuing action associated with session rotation trigger");
1985 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
1987 * TODO Add trigger identification (name/id) when
1988 * it is added to the API.
1990 * Not a fatal error.
1992 WARN("No space left when enqueuing action associated with session rotation trigger");
2000 notification_client_list_put(client_list
);
2001 if (caa_unlikely(ret
)) {
2006 session_info_put(session_info
);
2007 *_cmd_result
= cmd_result
;
2013 int handle_notification_thread_command_add_tracer_event_source(
2014 struct notification_thread_state
*state
,
2015 int tracer_event_source_fd
,
2016 enum lttng_domain_type domain_type
,
2017 enum lttng_error_code
*_cmd_result
)
2020 enum lttng_error_code cmd_result
= LTTNG_OK
;
2021 struct notification_event_tracer_event_source_element
*element
= NULL
;
2023 element
= zmalloc(sizeof(*element
));
2025 cmd_result
= LTTNG_ERR_NOMEM
;
2030 element
->fd
= tracer_event_source_fd
;
2031 element
->domain
= domain_type
;
2033 cds_list_add(&element
->node
, &state
->tracer_event_sources_list
);
2035 DBG3("Adding tracer event source fd to poll set: tracer_event_source_fd = %d, domain = '%s'",
2036 tracer_event_source_fd
,
2037 lttng_domain_type_str(domain_type
));
2039 /* Adding the read side pipe to the event poll. */
2040 ret
= lttng_poll_add(&state
->events
, tracer_event_source_fd
, LPOLLIN
| LPOLLERR
);
2042 ERR("Failed to add tracer event source to poll set: tracer_event_source_fd = %d, domain = '%s'",
2043 tracer_event_source_fd
,
2044 lttng_domain_type_str(element
->domain
));
2045 cds_list_del(&element
->node
);
2050 element
->is_fd_in_poll_set
= true;
2053 *_cmd_result
= cmd_result
;
2058 int drain_event_notifier_notification_pipe(
2059 struct notification_thread_state
*state
,
2060 int pipe
, enum lttng_domain_type domain
)
2062 struct lttng_poll_event events
= {0};
2065 ret
= lttng_poll_create(&events
, 1, LTTNG_CLOEXEC
);
2067 ERR("Error creating lttng_poll_event");
2071 ret
= lttng_poll_add(&events
, pipe
, LPOLLIN
);
2073 ERR("Error adding fd event notifier notification pipe to lttng_poll_event: fd = %d",
2080 * Continue to consume notifications as long as there are new
2081 * ones coming in. The tracer has been asked to stop producing
2084 * LPOLLIN is explicitly checked since LPOLLHUP is implicitly
2085 * monitored (on Linux, at least) and will be returned when
2086 * the pipe is closed but empty.
2088 ret
= lttng_poll_wait_interruptible(&events
, 0);
2089 if (ret
== 0 || (LTTNG_POLL_GETEV(&events
, 0) & LPOLLIN
) == 0) {
2090 /* No more notification to be read on this pipe. */
2093 } else if (ret
< 0) {
2094 PERROR("Failed on lttng_poll_wait_interruptible() call");
2099 ret
= handle_one_event_notifier_notification(state
, pipe
, domain
);
2101 ERR("Error consuming an event notifier notification from pipe: fd = %d",
2106 lttng_poll_clean(&events
);
2111 struct notification_event_tracer_event_source_element
*
2112 find_tracer_event_source_element(struct notification_thread_state
*state
,
2113 int tracer_event_source_fd
)
2115 struct notification_event_tracer_event_source_element
*source_element
;
2117 cds_list_for_each_entry(source_element
,
2118 &state
->tracer_event_sources_list
, node
) {
2119 if (source_element
->fd
== tracer_event_source_fd
) {
2124 source_element
= NULL
;
2126 return source_element
;
2130 int remove_tracer_event_source_from_pollset(
2131 struct notification_thread_state
*state
,
2132 struct notification_event_tracer_event_source_element
*source_element
)
2136 LTTNG_ASSERT(source_element
->is_fd_in_poll_set
);
2138 DBG3("Removing tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2140 lttng_domain_type_str(source_element
->domain
));
2142 /* Removing the fd from the event poll set. */
2143 ret
= lttng_poll_del(&state
->events
, source_element
->fd
);
2145 ERR("Failed to remove tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2147 lttng_domain_type_str(source_element
->domain
));
2152 source_element
->is_fd_in_poll_set
= false;
2155 * Force the notification thread to restart the poll() loop to ensure
2156 * that any events from the removed fd are removed.
2158 state
->restart_poll
= true;
2160 ret
= drain_event_notifier_notification_pipe(state
, source_element
->fd
,
2161 source_element
->domain
);
2163 ERR("Error draining event notifier notification: tracer_event_source_fd = %d, domain = %s",
2165 lttng_domain_type_str(source_element
->domain
));
2174 int handle_notification_thread_tracer_event_source_died(
2175 struct notification_thread_state
*state
,
2176 int tracer_event_source_fd
)
2179 struct notification_event_tracer_event_source_element
*source_element
;
2181 source_element
= find_tracer_event_source_element(state
,
2182 tracer_event_source_fd
);
2184 LTTNG_ASSERT(source_element
);
2186 ret
= remove_tracer_event_source_from_pollset(state
, source_element
);
2188 ERR("Failed to remove dead tracer event source from poll set");
2195 int handle_notification_thread_command_remove_tracer_event_source(
2196 struct notification_thread_state
*state
,
2197 int tracer_event_source_fd
,
2198 enum lttng_error_code
*_cmd_result
)
2201 enum lttng_error_code cmd_result
= LTTNG_OK
;
2202 struct notification_event_tracer_event_source_element
*source_element
= NULL
;
2204 source_element
= find_tracer_event_source_element(state
,
2205 tracer_event_source_fd
);
2207 LTTNG_ASSERT(source_element
);
2209 /* Remove the tracer source from the list. */
2210 cds_list_del(&source_element
->node
);
2212 if (!source_element
->is_fd_in_poll_set
) {
2213 /* Skip the poll set removal. */
2217 ret
= remove_tracer_event_source_from_pollset(state
, source_element
);
2219 ERR("Failed to remove tracer event source from poll set");
2220 cmd_result
= LTTNG_ERR_FATAL
;
2224 free(source_element
);
2225 *_cmd_result
= cmd_result
;
2229 static int handle_notification_thread_command_list_triggers(
2230 struct notification_thread_handle
*handle
,
2231 struct notification_thread_state
*state
,
2233 struct lttng_triggers
**triggers
,
2234 enum lttng_error_code
*_cmd_result
)
2237 enum lttng_error_code cmd_result
= LTTNG_OK
;
2238 struct cds_lfht_iter iter
;
2239 struct lttng_trigger_ht_element
*trigger_ht_element
;
2240 struct lttng_triggers
*local_triggers
= NULL
;
2241 const struct lttng_credentials
*creds
;
2245 local_triggers
= lttng_triggers_create();
2246 if (!local_triggers
) {
2247 /* Not a fatal error. */
2248 cmd_result
= LTTNG_ERR_NOMEM
;
2252 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
,
2253 trigger_ht_element
, node
) {
2255 * Only return the triggers to which the client has access.
2256 * The root user has visibility over all triggers.
2258 creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
2259 if (client_uid
!= lttng_credentials_get_uid(creds
) && client_uid
!= 0) {
2263 ret
= lttng_triggers_add(local_triggers
,
2264 trigger_ht_element
->trigger
);
2266 /* Not a fatal error. */
2268 cmd_result
= LTTNG_ERR_NOMEM
;
2273 /* Transferring ownership to the caller. */
2274 *triggers
= local_triggers
;
2275 local_triggers
= NULL
;
2279 lttng_triggers_destroy(local_triggers
);
2280 *_cmd_result
= cmd_result
;
2284 static inline void get_trigger_info_for_log(const struct lttng_trigger
*trigger
,
2285 const char **trigger_name
,
2286 uid_t
*trigger_owner_uid
)
2288 enum lttng_trigger_status trigger_status
;
2290 trigger_status
= lttng_trigger_get_name(trigger
, trigger_name
);
2291 switch (trigger_status
) {
2292 case LTTNG_TRIGGER_STATUS_OK
:
2294 case LTTNG_TRIGGER_STATUS_UNSET
:
2295 *trigger_name
= "(anonymous)";
2301 trigger_status
= lttng_trigger_get_owner_uid(trigger
,
2303 LTTNG_ASSERT(trigger_status
== LTTNG_TRIGGER_STATUS_OK
);
2306 static int handle_notification_thread_command_get_trigger(
2307 struct notification_thread_state
*state
,
2308 const struct lttng_trigger
*trigger
,
2309 struct lttng_trigger
**registered_trigger
,
2310 enum lttng_error_code
*_cmd_result
)
2313 struct cds_lfht_iter iter
;
2314 struct lttng_trigger_ht_element
*trigger_ht_element
;
2315 enum lttng_error_code cmd_result
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
2316 const char *trigger_name
;
2317 uid_t trigger_owner_uid
;
2321 cds_lfht_for_each_entry(
2322 state
->triggers_ht
, &iter
, trigger_ht_element
, node
) {
2323 if (lttng_trigger_is_equal(
2324 trigger
, trigger_ht_element
->trigger
)) {
2325 /* Take one reference on the return trigger. */
2326 *registered_trigger
= trigger_ht_element
->trigger
;
2327 lttng_trigger_get(*registered_trigger
);
2329 cmd_result
= LTTNG_OK
;
2334 /* Not a fatal error if the trigger is not found. */
2335 get_trigger_info_for_log(trigger
, &trigger_name
, &trigger_owner_uid
);
2336 DBG("Failed to retrieve registered version of trigger: trigger name = '%s', trigger owner uid = %d",
2337 trigger_name
, (int) trigger_owner_uid
);
2343 *_cmd_result
= cmd_result
;
2348 bool condition_is_supported(struct lttng_condition
*condition
)
2352 switch (lttng_condition_get_type(condition
)) {
2353 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
2354 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
2357 enum lttng_domain_type domain
;
2359 ret
= lttng_condition_buffer_usage_get_domain_type(condition
,
2361 LTTNG_ASSERT(ret
== 0);
2363 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2364 is_supported
= true;
2369 * Older kernel tracers don't expose the API to monitor their
2370 * buffers. Therefore, we reject triggers that require that
2371 * mechanism to be available to be evaluated.
2373 * Assume unsupported on error.
2375 is_supported
= kernel_supports_ring_buffer_snapshot_sample_positions() == 1;
2378 case LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES
:
2380 const struct lttng_event_rule
*event_rule
;
2381 enum lttng_domain_type domain
;
2382 const enum lttng_condition_status status
=
2383 lttng_condition_event_rule_matches_get_rule(
2384 condition
, &event_rule
);
2386 LTTNG_ASSERT(status
== LTTNG_CONDITION_STATUS_OK
);
2388 domain
= lttng_event_rule_get_domain_type(event_rule
);
2389 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2390 is_supported
= true;
2395 * Older kernel tracers can't emit notification. Therefore, we
2396 * reject triggers that require that mechanism to be available
2399 * Assume unsupported on error.
2401 is_supported
= kernel_supports_event_notifiers() == 1;
2405 is_supported
= true;
2408 return is_supported
;
2411 /* Must be called with RCU read lock held. */
2413 int bind_trigger_to_matching_session(struct lttng_trigger
*trigger
,
2414 struct notification_thread_state
*state
)
2417 const struct lttng_condition
*condition
;
2418 const char *session_name
;
2419 struct lttng_session_trigger_list
*trigger_list
;
2421 condition
= lttng_trigger_get_const_condition(trigger
);
2422 switch (lttng_condition_get_type(condition
)) {
2423 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
2424 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
2426 enum lttng_condition_status status
;
2428 status
= lttng_condition_session_rotation_get_session_name(
2429 condition
, &session_name
);
2430 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
2431 ERR("Failed to bind trigger to session: unable to get 'session_rotation' condition's session name");
2442 trigger_list
= get_session_trigger_list(state
, session_name
);
2443 if (!trigger_list
) {
2444 DBG("Unable to bind trigger applying to session \"%s\" as it is not yet known to the notification system",
2450 DBG("Newly registered trigger bound to session \"%s\"",
2452 ret
= lttng_session_trigger_list_add(trigger_list
, trigger
);
2457 /* Must be called with RCU read lock held. */
2459 int bind_trigger_to_matching_channels(struct lttng_trigger
*trigger
,
2460 struct notification_thread_state
*state
)
2463 struct cds_lfht_node
*node
;
2464 struct cds_lfht_iter iter
;
2465 struct channel_info
*channel
;
2467 cds_lfht_for_each_entry(state
->channels_ht
, &iter
, channel
,
2469 struct lttng_trigger_list_element
*trigger_list_element
;
2470 struct lttng_channel_trigger_list
*trigger_list
;
2471 struct cds_lfht_iter lookup_iter
;
2473 if (!trigger_applies_to_channel(trigger
, channel
)) {
2477 cds_lfht_lookup(state
->channel_triggers_ht
,
2478 hash_channel_key(&channel
->key
),
2479 match_channel_trigger_list
,
2482 node
= cds_lfht_iter_get_node(&lookup_iter
);
2484 trigger_list
= caa_container_of(node
,
2485 struct lttng_channel_trigger_list
,
2486 channel_triggers_ht_node
);
2488 trigger_list_element
= zmalloc(sizeof(*trigger_list_element
));
2489 if (!trigger_list_element
) {
2493 CDS_INIT_LIST_HEAD(&trigger_list_element
->node
);
2494 trigger_list_element
->trigger
= trigger
;
2495 cds_list_add(&trigger_list_element
->node
, &trigger_list
->list
);
2496 DBG("Newly registered trigger bound to channel \"%s\"",
2504 bool is_trigger_action_notify(const struct lttng_trigger
*trigger
)
2506 bool is_notify
= false;
2507 unsigned int i
, count
;
2508 enum lttng_action_status action_status
;
2509 const struct lttng_action
*action
=
2510 lttng_trigger_get_const_action(trigger
);
2511 enum lttng_action_type action_type
;
2513 LTTNG_ASSERT(action
);
2514 action_type
= lttng_action_get_type(action
);
2515 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2518 } else if (action_type
!= LTTNG_ACTION_TYPE_LIST
) {
2522 action_status
= lttng_action_list_get_count(action
, &count
);
2523 LTTNG_ASSERT(action_status
== LTTNG_ACTION_STATUS_OK
);
2525 for (i
= 0; i
< count
; i
++) {
2526 const struct lttng_action
*inner_action
=
2527 lttng_action_list_get_at_index(
2530 action_type
= lttng_action_get_type(inner_action
);
2531 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2541 static bool trigger_name_taken(struct notification_thread_state
*state
,
2542 const struct lttng_trigger
*trigger
)
2544 struct cds_lfht_iter iter
;
2547 * No duplicata is allowed in the triggers_by_name_uid_ht.
2548 * The match is done against the trigger name and uid.
2550 cds_lfht_lookup(state
->triggers_by_name_uid_ht
,
2551 hash_trigger_by_name_uid(trigger
),
2552 match_trigger_by_name_uid
,
2555 return !!cds_lfht_iter_get_node(&iter
);
2559 enum lttng_error_code
generate_trigger_name(
2560 struct notification_thread_state
*state
,
2561 struct lttng_trigger
*trigger
, const char **name
)
2563 enum lttng_error_code ret_code
= LTTNG_OK
;
2565 enum lttng_trigger_status status
;
2568 const int ret
= lttng_trigger_generate_name(trigger
,
2569 state
->trigger_id
.name_offset
++);
2571 /* The only reason this can fail right now. */
2572 ret_code
= LTTNG_ERR_NOMEM
;
2576 status
= lttng_trigger_get_name(trigger
, name
);
2577 LTTNG_ASSERT(status
== LTTNG_TRIGGER_STATUS_OK
);
2579 taken
= trigger_name_taken(state
, trigger
);
2580 } while (taken
|| state
->trigger_id
.name_offset
== UINT64_MAX
);
2586 void notif_thread_state_remove_trigger_ht_elem(
2587 struct notification_thread_state
*state
,
2588 struct lttng_trigger_ht_element
*trigger_ht_element
)
2590 LTTNG_ASSERT(state
);
2591 LTTNG_ASSERT(trigger_ht_element
);
2593 cds_lfht_del(state
->triggers_ht
, &trigger_ht_element
->node
);
2594 cds_lfht_del(state
->triggers_by_name_uid_ht
, &trigger_ht_element
->node_by_name_uid
);
2598 enum lttng_error_code
setup_tracer_notifier(
2599 struct notification_thread_state
*state
,
2600 struct lttng_trigger
*trigger
)
2602 enum lttng_error_code ret
;
2603 enum event_notifier_error_accounting_status error_accounting_status
;
2604 struct cds_lfht_node
*node
;
2605 uint64_t error_counter_index
= 0;
2606 struct lttng_condition
*condition
= lttng_trigger_get_condition(trigger
);
2607 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
= NULL
;
2609 trigger_tokens_ht_element
= zmalloc(sizeof(*trigger_tokens_ht_element
));
2610 if (!trigger_tokens_ht_element
) {
2611 ret
= LTTNG_ERR_NOMEM
;
2615 /* Add trigger token to the trigger_tokens_ht. */
2616 cds_lfht_node_init(&trigger_tokens_ht_element
->node
);
2617 trigger_tokens_ht_element
->token
= LTTNG_OPTIONAL_GET(trigger
->tracer_token
);
2618 trigger_tokens_ht_element
->trigger
= trigger
;
2620 node
= cds_lfht_add_unique(state
->trigger_tokens_ht
,
2621 hash_key_u64(&trigger_tokens_ht_element
->token
, lttng_ht_seed
),
2622 match_trigger_token
,
2623 &trigger_tokens_ht_element
->token
,
2624 &trigger_tokens_ht_element
->node
);
2625 if (node
!= &trigger_tokens_ht_element
->node
) {
2626 ret
= LTTNG_ERR_TRIGGER_EXISTS
;
2627 goto error_free_ht_element
;
2630 error_accounting_status
= event_notifier_error_accounting_register_event_notifier(
2631 trigger
, &error_counter_index
);
2632 if (error_accounting_status
!= EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK
) {
2633 if (error_accounting_status
== EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_NO_INDEX_AVAILABLE
) {
2634 DBG("Trigger list error accounting counter full.");
2635 ret
= LTTNG_ERR_EVENT_NOTIFIER_ERROR_ACCOUNTING_FULL
;
2637 ERR("Error registering trigger for error accounting");
2638 ret
= LTTNG_ERR_EVENT_NOTIFIER_REGISTRATION
;
2641 goto error_remove_ht_element
;
2644 lttng_condition_event_rule_matches_set_error_counter_index(
2645 condition
, error_counter_index
);
2650 error_remove_ht_element
:
2651 cds_lfht_del(state
->trigger_tokens_ht
, &trigger_tokens_ht_element
->node
);
2652 error_free_ht_element
:
2653 free(trigger_tokens_ht_element
);
2659 * FIXME A client's credentials are not checked when registering a trigger.
2661 * The effects of this are benign since:
2662 * - The client will succeed in registering the trigger, as it is valid,
2663 * - The trigger will, internally, be bound to the channel/session,
2664 * - The notifications will not be sent since the client's credentials
2665 * are checked against the channel at that moment.
2667 * If this function returns a non-zero value, it means something is
2668 * fundamentally broken and the whole subsystem/thread will be torn down.
2670 * If a non-fatal error occurs, just set the cmd_result to the appropriate
2674 int handle_notification_thread_command_register_trigger(
2675 struct notification_thread_state
*state
,
2676 struct lttng_trigger
*trigger
,
2677 bool is_trigger_anonymous
,
2678 enum lttng_error_code
*cmd_result
)
2681 struct lttng_condition
*condition
;
2682 struct notification_client_list
*client_list
= NULL
;
2683 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2684 struct cds_lfht_node
*node
;
2685 const char* trigger_name
;
2686 bool free_trigger
= true;
2687 struct lttng_evaluation
*evaluation
= NULL
;
2688 struct lttng_credentials object_creds
;
2691 enum action_executor_status executor_status
;
2692 const uint64_t trigger_tracer_token
=
2693 state
->trigger_id
.next_tracer_token
++;
2697 /* Set the trigger's tracer token. */
2698 lttng_trigger_set_tracer_token(trigger
, trigger_tracer_token
);
2700 if (!is_trigger_anonymous
) {
2701 if (lttng_trigger_get_name(trigger
, &trigger_name
) ==
2702 LTTNG_TRIGGER_STATUS_UNSET
) {
2703 const enum lttng_error_code ret_code
=
2704 generate_trigger_name(state
, trigger
,
2707 if (ret_code
!= LTTNG_OK
) {
2710 *cmd_result
= ret_code
;
2713 } else if (trigger_name_taken(state
, trigger
)) {
2714 /* Not a fatal error. */
2715 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2720 trigger_name
= "(anonymous)";
2723 condition
= lttng_trigger_get_condition(trigger
);
2724 LTTNG_ASSERT(condition
);
2726 /* Some conditions require tracers to implement a minimal ABI version. */
2727 if (!condition_is_supported(condition
)) {
2728 *cmd_result
= LTTNG_ERR_NOT_SUPPORTED
;
2732 trigger_ht_element
= zmalloc(sizeof(*trigger_ht_element
));
2733 if (!trigger_ht_element
) {
2738 /* Add trigger to the trigger_ht. */
2739 cds_lfht_node_init(&trigger_ht_element
->node
);
2740 cds_lfht_node_init(&trigger_ht_element
->node_by_name_uid
);
2741 trigger_ht_element
->trigger
= trigger
;
2743 node
= cds_lfht_add_unique(state
->triggers_ht
,
2744 lttng_condition_hash(condition
),
2747 &trigger_ht_element
->node
);
2748 if (node
!= &trigger_ht_element
->node
) {
2749 /* Not a fatal error, simply report it to the client. */
2750 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2751 goto error_free_ht_element
;
2754 node
= cds_lfht_add_unique(state
->triggers_by_name_uid_ht
,
2755 hash_trigger_by_name_uid(trigger
),
2756 match_trigger_by_name_uid
,
2758 &trigger_ht_element
->node_by_name_uid
);
2759 if (node
!= &trigger_ht_element
->node_by_name_uid
) {
2760 /* Internal error: add to triggers_ht should have failed. */
2762 goto error_free_ht_element
;
2765 /* From this point consider the trigger registered. */
2766 lttng_trigger_set_as_registered(trigger
);
2769 * Some triggers might need a tracer notifier depending on its
2770 * condition and actions.
2772 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
2773 enum lttng_error_code error_code
;
2775 error_code
= setup_tracer_notifier(state
, trigger
);
2776 if (error_code
!= LTTNG_OK
) {
2777 notif_thread_state_remove_trigger_ht_elem(state
,
2778 trigger_ht_element
);
2779 if (error_code
== LTTNG_ERR_NOMEM
) {
2782 *cmd_result
= error_code
;
2786 goto error_free_ht_element
;
2791 * The rest only applies to triggers that have a "notify" action.
2792 * It is not skipped as this is the only action type currently
2795 if (is_trigger_action_notify(trigger
)) {
2797 * Find or create the client list of this condition. It may
2798 * already be present if another trigger is already registered
2799 * with the same condition.
2801 client_list
= get_client_list_from_condition(state
, condition
);
2804 * No client list for this condition yet. We create new
2805 * one and build it up.
2807 client_list
= notification_client_list_create(state
, condition
);
2809 ERR("Error creating notification client list for trigger %s", trigger
->name
);
2810 goto error_free_ht_element
;
2814 CDS_INIT_LIST_HEAD(&trigger_ht_element
->client_list_trigger_node
);
2816 pthread_mutex_lock(&client_list
->lock
);
2817 cds_list_add(&trigger_ht_element
->client_list_trigger_node
, &client_list
->triggers_list
);
2818 pthread_mutex_unlock(&client_list
->lock
);
2822 * Ownership of the trigger and of its wrapper was transfered to
2823 * the triggers_ht. Same for token ht element if necessary.
2825 trigger_ht_element
= NULL
;
2826 free_trigger
= false;
2828 switch (get_condition_binding_object(condition
)) {
2829 case LTTNG_OBJECT_TYPE_SESSION
:
2830 /* Add the trigger to the list if it matches a known session. */
2831 ret
= bind_trigger_to_matching_session(trigger
, state
);
2833 goto error_free_ht_element
;
2836 case LTTNG_OBJECT_TYPE_CHANNEL
:
2838 * Add the trigger to list of triggers bound to the channels
2841 ret
= bind_trigger_to_matching_channels(trigger
, state
);
2843 goto error_free_ht_element
;
2846 case LTTNG_OBJECT_TYPE_NONE
:
2849 ERR("Unknown object type on which to bind a newly registered trigger was encountered");
2851 goto error_free_ht_element
;
2855 * The new trigger's condition must be evaluated against the current
2858 * In the case of `notify` action, nothing preventing clients from
2859 * subscribing to a condition before the corresponding trigger is
2860 * registered, we have to evaluate this new condition right away.
2862 * At some point, we were waiting for the next "evaluation" (e.g. on
2863 * reception of a channel sample) to evaluate this new condition, but
2866 * The reason it was broken is that waiting for the next sample
2867 * does not allow us to properly handle transitions for edge-triggered
2870 * Consider this example: when we handle a new channel sample, we
2871 * evaluate each conditions twice: once with the previous state, and
2872 * again with the newest state. We then use those two results to
2873 * determine whether a state change happened: a condition was false and
2874 * became true. If a state change happened, we have to notify clients.
2876 * Now, if a client subscribes to a given notification and registers
2877 * a trigger *after* that subscription, we have to make sure the
2878 * condition is evaluated at this point while considering only the
2879 * current state. Otherwise, the next evaluation cycle may only see
2880 * that the evaluations remain the same (true for samples n-1 and n) and
2881 * the client will never know that the condition has been met.
2883 switch (get_condition_binding_object(condition
)) {
2884 case LTTNG_OBJECT_TYPE_SESSION
:
2885 ret
= evaluate_session_condition_for_client(condition
, state
,
2886 &evaluation
, &object_uid
,
2888 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2889 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2891 case LTTNG_OBJECT_TYPE_CHANNEL
:
2892 ret
= evaluate_channel_condition_for_client(condition
, state
,
2893 &evaluation
, &object_uid
,
2895 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2896 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2898 case LTTNG_OBJECT_TYPE_NONE
:
2901 case LTTNG_OBJECT_TYPE_UNKNOWN
:
2909 goto error_free_ht_element
;
2912 DBG("Newly registered trigger's condition evaluated to %s",
2913 evaluation
? "true" : "false");
2915 /* Evaluation yielded nothing. Normal exit. */
2921 * Ownership of `evaluation` transferred to the action executor
2922 * no matter the result.
2924 executor_status
= action_executor_enqueue_trigger(state
->executor
,
2925 trigger
, evaluation
, &object_creds
, client_list
);
2927 switch (executor_status
) {
2928 case ACTION_EXECUTOR_STATUS_OK
:
2930 case ACTION_EXECUTOR_STATUS_ERROR
:
2931 case ACTION_EXECUTOR_STATUS_INVALID
:
2933 * TODO Add trigger identification (name/id) when
2934 * it is added to the API.
2936 ERR("Fatal error occurred while enqueuing action associated to newly registered trigger");
2938 goto error_free_ht_element
;
2939 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
2941 * TODO Add trigger identification (name/id) when
2942 * it is added to the API.
2944 * Not a fatal error.
2946 WARN("No space left when enqueuing action associated to newly registered trigger");
2954 *cmd_result
= LTTNG_OK
;
2955 DBG("Registered trigger: name = `%s`, tracer token = %" PRIu64
,
2956 trigger_name
, trigger_tracer_token
);
2959 error_free_ht_element
:
2960 if (trigger_ht_element
) {
2961 /* Delayed removal due to RCU constraint on delete. */
2962 call_rcu(&trigger_ht_element
->rcu_node
,
2963 free_lttng_trigger_ht_element_rcu
);
2968 * Other objects might have a reference to the trigger, mark it
2971 lttng_trigger_set_as_unregistered(trigger
);
2972 lttng_trigger_destroy(trigger
);
2980 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
)
2982 free(caa_container_of(node
, struct lttng_trigger_ht_element
,
2987 void free_notification_trigger_tokens_ht_element_rcu(struct rcu_head
*node
)
2989 free(caa_container_of(node
, struct notification_trigger_tokens_ht_element
,
2994 void teardown_tracer_notifier(struct notification_thread_state
*state
,
2995 const struct lttng_trigger
*trigger
)
2997 struct cds_lfht_iter iter
;
2998 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
;
3000 cds_lfht_for_each_entry(state
->trigger_tokens_ht
, &iter
,
3001 trigger_tokens_ht_element
, node
) {
3003 if (!lttng_trigger_is_equal(trigger
,
3004 trigger_tokens_ht_element
->trigger
)) {
3008 event_notifier_error_accounting_unregister_event_notifier(
3009 trigger_tokens_ht_element
->trigger
);
3011 /* TODO talk to all app and remove it */
3012 DBG("Removed trigger from tokens_ht");
3013 cds_lfht_del(state
->trigger_tokens_ht
,
3014 &trigger_tokens_ht_element
->node
);
3016 call_rcu(&trigger_tokens_ht_element
->rcu_node
,
3017 free_notification_trigger_tokens_ht_element_rcu
);
3024 int handle_notification_thread_command_unregister_trigger(
3025 struct notification_thread_state
*state
,
3026 const struct lttng_trigger
*trigger
,
3027 enum lttng_error_code
*_cmd_reply
)
3029 struct cds_lfht_iter iter
;
3030 struct cds_lfht_node
*triggers_ht_node
;
3031 struct lttng_channel_trigger_list
*trigger_list
;
3032 struct notification_client_list
*client_list
;
3033 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
3034 const struct lttng_condition
*condition
= lttng_trigger_get_const_condition(
3036 enum lttng_error_code cmd_reply
;
3040 cds_lfht_lookup(state
->triggers_ht
,
3041 lttng_condition_hash(condition
),
3045 triggers_ht_node
= cds_lfht_iter_get_node(&iter
);
3046 if (!triggers_ht_node
) {
3047 cmd_reply
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
3050 cmd_reply
= LTTNG_OK
;
3053 trigger_ht_element
= caa_container_of(triggers_ht_node
,
3054 struct lttng_trigger_ht_element
, node
);
3056 /* Remove trigger from channel_triggers_ht. */
3057 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
, trigger_list
,
3058 channel_triggers_ht_node
) {
3059 struct lttng_trigger_list_element
*trigger_element
, *tmp
;
3061 cds_list_for_each_entry_safe(trigger_element
, tmp
,
3062 &trigger_list
->list
, node
) {
3063 if (!lttng_trigger_is_equal(trigger
, trigger_element
->trigger
)) {
3067 DBG("Removed trigger from channel_triggers_ht");
3068 cds_list_del(&trigger_element
->node
);
3069 /* A trigger can only appear once per channel */
3074 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
3075 teardown_tracer_notifier(state
, trigger
);
3078 if (is_trigger_action_notify(trigger
)) {
3080 * Remove and release the client list from
3081 * notification_trigger_clients_ht.
3083 client_list
= get_client_list_from_condition(state
, condition
);
3084 LTTNG_ASSERT(client_list
);
3086 pthread_mutex_lock(&client_list
->lock
);
3087 cds_list_del(&trigger_ht_element
->client_list_trigger_node
);
3088 pthread_mutex_unlock(&client_list
->lock
);
3090 /* Put new reference and the hashtable's reference. */
3091 notification_client_list_put(client_list
);
3092 notification_client_list_put(client_list
);
3096 /* Remove trigger from triggers_ht. */
3097 notif_thread_state_remove_trigger_ht_elem(state
, trigger_ht_element
);
3099 /* Release the ownership of the trigger. */
3100 lttng_trigger_destroy(trigger_ht_element
->trigger
);
3101 call_rcu(&trigger_ht_element
->rcu_node
, free_lttng_trigger_ht_element_rcu
);
3105 *_cmd_reply
= cmd_reply
;
3110 /* Returns 0 on success, 1 on exit requested, negative value on error. */
3111 int handle_notification_thread_command(
3112 struct notification_thread_handle
*handle
,
3113 struct notification_thread_state
*state
)
3117 struct notification_thread_command
*cmd
;
3119 /* Read the event pipe to put it back into a quiescent state. */
3120 ret
= lttng_read(lttng_pipe_get_readfd(handle
->cmd_queue
.event_pipe
), &counter
,
3122 if (ret
!= sizeof(counter
)) {
3126 pthread_mutex_lock(&handle
->cmd_queue
.lock
);
3127 cmd
= cds_list_first_entry(&handle
->cmd_queue
.list
,
3128 struct notification_thread_command
, cmd_list_node
);
3129 cds_list_del(&cmd
->cmd_list_node
);
3130 pthread_mutex_unlock(&handle
->cmd_queue
.lock
);
3132 DBG("Received `%s` command",
3133 notification_command_type_str(cmd
->type
));
3134 switch (cmd
->type
) {
3135 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
3136 ret
= handle_notification_thread_command_register_trigger(state
,
3137 cmd
->parameters
.register_trigger
.trigger
,
3138 cmd
->parameters
.register_trigger
.is_trigger_anonymous
,
3141 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
3142 ret
= handle_notification_thread_command_unregister_trigger(
3144 cmd
->parameters
.unregister_trigger
.trigger
,
3147 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
3148 ret
= handle_notification_thread_command_add_channel(
3150 cmd
->parameters
.add_channel
.session
.name
,
3151 cmd
->parameters
.add_channel
.session
.uid
,
3152 cmd
->parameters
.add_channel
.session
.gid
,
3153 cmd
->parameters
.add_channel
.channel
.name
,
3154 cmd
->parameters
.add_channel
.channel
.domain
,
3155 cmd
->parameters
.add_channel
.channel
.key
,
3156 cmd
->parameters
.add_channel
.channel
.capacity
,
3159 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
3160 ret
= handle_notification_thread_command_remove_channel(
3161 state
, cmd
->parameters
.remove_channel
.key
,
3162 cmd
->parameters
.remove_channel
.domain
,
3165 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
3166 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
3167 ret
= handle_notification_thread_command_session_rotation(
3170 cmd
->parameters
.session_rotation
.session_name
,
3171 cmd
->parameters
.session_rotation
.uid
,
3172 cmd
->parameters
.session_rotation
.gid
,
3173 cmd
->parameters
.session_rotation
.trace_archive_chunk_id
,
3174 cmd
->parameters
.session_rotation
.location
,
3177 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
3178 ret
= handle_notification_thread_command_add_tracer_event_source(
3180 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3181 cmd
->parameters
.tracer_event_source
.domain
,
3184 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
3185 ret
= handle_notification_thread_command_remove_tracer_event_source(
3187 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3190 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
3192 struct lttng_triggers
*triggers
= NULL
;
3194 ret
= handle_notification_thread_command_list_triggers(
3197 cmd
->parameters
.list_triggers
.uid
,
3200 cmd
->reply
.list_triggers
.triggers
= triggers
;
3204 case NOTIFICATION_COMMAND_TYPE_QUIT
:
3205 cmd
->reply_code
= LTTNG_OK
;
3208 case NOTIFICATION_COMMAND_TYPE_GET_TRIGGER
:
3210 struct lttng_trigger
*trigger
= NULL
;
3212 ret
= handle_notification_thread_command_get_trigger(state
,
3213 cmd
->parameters
.get_trigger
.trigger
, &trigger
,
3215 cmd
->reply
.get_trigger
.trigger
= trigger
;
3218 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
3220 const enum client_transmission_status client_status
=
3221 cmd
->parameters
.client_communication_update
3223 const notification_client_id client_id
=
3224 cmd
->parameters
.client_communication_update
.id
;
3225 struct notification_client
*client
;
3228 client
= get_client_from_id(client_id
, state
);
3232 * Client error was probably already picked-up by the
3233 * notification thread or it has disconnected
3234 * gracefully while this command was queued.
3236 DBG("Failed to find notification client to update communication status, client id = %" PRIu64
,
3240 ret
= client_handle_transmission_status(
3241 client
, client_status
, state
);
3247 ERR("Unknown internal command received");
3255 if (cmd
->is_async
) {
3259 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3263 /* Wake-up and return a fatal error to the calling thread. */
3264 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3265 cmd
->reply_code
= LTTNG_ERR_FATAL
;
3267 /* Indicate a fatal error to the caller. */
3272 int socket_set_non_blocking(int socket
)
3276 /* Set the pipe as non-blocking. */
3277 ret
= fcntl(socket
, F_GETFL
, 0);
3279 PERROR("fcntl get socket flags");
3284 ret
= fcntl(socket
, F_SETFL
, flags
| O_NONBLOCK
);
3286 PERROR("fcntl set O_NONBLOCK socket flag");
3289 DBG("Client socket (fd = %i) set as non-blocking", socket
);
3295 int client_reset_inbound_state(struct notification_client
*client
)
3300 lttng_payload_clear(&client
->communication
.inbound
.payload
);
3302 client
->communication
.inbound
.bytes_to_receive
=
3303 sizeof(struct lttng_notification_channel_message
);
3304 client
->communication
.inbound
.msg_type
=
3305 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
;
3306 LTTNG_SOCK_SET_UID_CRED(&client
->communication
.inbound
.creds
, -1);
3307 LTTNG_SOCK_SET_GID_CRED(&client
->communication
.inbound
.creds
, -1);
3308 ret
= lttng_dynamic_buffer_set_size(
3309 &client
->communication
.inbound
.payload
.buffer
,
3310 client
->communication
.inbound
.bytes_to_receive
);
3315 int handle_notification_thread_client_connect(
3316 struct notification_thread_state
*state
)
3319 struct notification_client
*client
;
3321 DBG("Handling new notification channel client connection");
3323 client
= zmalloc(sizeof(*client
));
3330 pthread_mutex_init(&client
->lock
, NULL
);
3331 client
->id
= state
->next_notification_client_id
++;
3332 CDS_INIT_LIST_HEAD(&client
->condition_list
);
3333 lttng_payload_init(&client
->communication
.inbound
.payload
);
3334 lttng_payload_init(&client
->communication
.outbound
.payload
);
3335 client
->communication
.inbound
.expect_creds
= true;
3337 ret
= client_reset_inbound_state(client
);
3339 ERR("Failed to reset client communication's inbound state");
3344 ret
= lttcomm_accept_unix_sock(state
->notification_channel_socket
);
3346 ERR("Failed to accept new notification channel client connection");
3351 client
->socket
= ret
;
3353 ret
= socket_set_non_blocking(client
->socket
);
3355 ERR("Failed to set new notification channel client connection socket as non-blocking");
3359 ret
= lttcomm_setsockopt_creds_unix_sock(client
->socket
);
3361 ERR("Failed to set socket options on new notification channel client socket");
3366 ret
= lttng_poll_add(&state
->events
, client
->socket
,
3367 LPOLLIN
| LPOLLERR
|
3368 LPOLLHUP
| LPOLLRDHUP
);
3370 ERR("Failed to add notification channel client socket to poll set");
3374 DBG("Added new notification channel client socket (%i) to poll set",
3378 cds_lfht_add(state
->client_socket_ht
,
3379 hash_client_socket(client
->socket
),
3380 &client
->client_socket_ht_node
);
3381 cds_lfht_add(state
->client_id_ht
,
3382 hash_client_id(client
->id
),
3383 &client
->client_id_ht_node
);
3389 notification_client_destroy(client
, state
);
3394 * RCU read-lock must be held by the caller.
3395 * Client lock must _not_ be held by the caller.
3398 int notification_thread_client_disconnect(
3399 struct notification_client
*client
,
3400 struct notification_thread_state
*state
)
3403 struct lttng_condition_list_element
*condition_list_element
, *tmp
;
3405 /* Acquire the client lock to disable its communication atomically. */
3406 pthread_mutex_lock(&client
->lock
);
3407 client
->communication
.active
= false;
3408 cds_lfht_del(state
->client_socket_ht
, &client
->client_socket_ht_node
);
3409 cds_lfht_del(state
->client_id_ht
, &client
->client_id_ht_node
);
3410 pthread_mutex_unlock(&client
->lock
);
3412 ret
= lttng_poll_del(&state
->events
, client
->socket
);
3414 ERR("Failed to remove client socket %d from poll set",
3418 /* Release all conditions to which the client was subscribed. */
3419 cds_list_for_each_entry_safe(condition_list_element
, tmp
,
3420 &client
->condition_list
, node
) {
3421 (void) notification_thread_client_unsubscribe(client
,
3422 condition_list_element
->condition
, state
, NULL
);
3426 * Client no longer accessible to other threads (through the
3429 notification_client_destroy(client
, state
);
3433 int handle_notification_thread_client_disconnect(
3434 int client_socket
, struct notification_thread_state
*state
)
3437 struct notification_client
*client
;
3440 DBG("Closing client connection (socket fd = %i)",
3442 client
= get_client_from_socket(client_socket
, state
);
3444 /* Internal state corruption, fatal error. */
3445 ERR("Unable to find client (socket fd = %i)",
3451 ret
= notification_thread_client_disconnect(client
, state
);
3457 int handle_notification_thread_client_disconnect_all(
3458 struct notification_thread_state
*state
)
3460 struct cds_lfht_iter iter
;
3461 struct notification_client
*client
;
3462 bool error_encoutered
= false;
3465 DBG("Closing all client connections");
3466 cds_lfht_for_each_entry(state
->client_socket_ht
, &iter
, client
,
3467 client_socket_ht_node
) {
3470 ret
= notification_thread_client_disconnect(
3473 error_encoutered
= true;
3477 return error_encoutered
? 1 : 0;
3480 int handle_notification_thread_trigger_unregister_all(
3481 struct notification_thread_state
*state
)
3483 bool error_occurred
= false;
3484 struct cds_lfht_iter iter
;
3485 struct lttng_trigger_ht_element
*trigger_ht_element
;
3488 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
3490 int ret
= handle_notification_thread_command_unregister_trigger(
3491 state
, trigger_ht_element
->trigger
, NULL
);
3493 error_occurred
= true;
3497 return error_occurred
? -1 : 0;
3501 int client_handle_transmission_status(
3502 struct notification_client
*client
,
3503 enum client_transmission_status transmission_status
,
3504 struct notification_thread_state
*state
)
3508 switch (transmission_status
) {
3509 case CLIENT_TRANSMISSION_STATUS_COMPLETE
:
3510 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3511 CLIENT_POLL_MASK_IN
);
3517 case CLIENT_TRANSMISSION_STATUS_QUEUED
:
3519 * We want to be notified whenever there is buffer space
3520 * available to send the rest of the payload.
3522 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3523 CLIENT_POLL_MASK_IN_OUT
);
3528 case CLIENT_TRANSMISSION_STATUS_FAIL
:
3529 ret
= notification_thread_client_disconnect(client
, state
);
3534 case CLIENT_TRANSMISSION_STATUS_ERROR
:
3544 /* Client lock must be acquired by caller. */
3546 enum client_transmission_status
client_flush_outgoing_queue(
3547 struct notification_client
*client
)
3550 size_t to_send_count
;
3551 enum client_transmission_status status
;
3552 struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3553 &client
->communication
.outbound
.payload
, 0, -1);
3554 const int fds_to_send_count
=
3555 lttng_payload_view_get_fd_handle_count(&pv
);
3557 ASSERT_LOCKED(client
->lock
);
3559 if (!client
->communication
.active
) {
3560 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3564 if (pv
.buffer
.size
== 0) {
3566 * If both data and fds are equal to zero, we are in an invalid
3569 LTTNG_ASSERT(fds_to_send_count
!= 0);
3574 to_send_count
= pv
.buffer
.size
;
3575 DBG("Flushing client (socket fd = %i) outgoing queue",
3578 ret
= lttcomm_send_unix_sock_non_block(client
->socket
,
3581 if ((ret
>= 0 && ret
< to_send_count
)) {
3582 DBG("Client (socket fd = %i) outgoing queue could not be completely flushed",
3584 to_send_count
-= max(ret
, 0);
3586 memmove(client
->communication
.outbound
.payload
.buffer
.data
,
3588 pv
.buffer
.size
- to_send_count
,
3590 ret
= lttng_dynamic_buffer_set_size(
3591 &client
->communication
.outbound
.payload
.buffer
,
3597 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3599 } else if (ret
< 0) {
3600 /* Generic error, disable the client's communication. */
3601 ERR("Failed to flush outgoing queue, disconnecting client (socket fd = %i)",
3603 client
->communication
.active
= false;
3604 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3608 * No error and flushed the queue completely.
3610 * The payload buffer size is used later to
3611 * check if there is notifications queued. So albeit that the
3612 * direct caller knows that the transmission is complete, we
3613 * need to set the buffer size to zero.
3615 ret
= lttng_dynamic_buffer_set_size(
3616 &client
->communication
.outbound
.payload
.buffer
, 0);
3623 /* No fds to send, transmission is complete. */
3624 if (fds_to_send_count
== 0) {
3625 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3629 ret
= lttcomm_send_payload_view_fds_unix_sock_non_block(
3630 client
->socket
, &pv
);
3632 /* Generic error, disable the client's communication. */
3633 ERR("Failed to flush outgoing fds queue, disconnecting client (socket fd = %i)",
3635 client
->communication
.active
= false;
3636 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3638 } else if (ret
== 0) {
3639 /* Nothing could be sent. */
3640 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3642 /* Fd passing is an all or nothing kind of thing. */
3643 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3645 * The payload _fd_array count is used later to
3646 * check if there is notifications queued. So although the
3647 * direct caller knows that the transmission is complete, we
3648 * need to clear the _fd_array for the queuing check.
3650 lttng_dynamic_pointer_array_clear(
3651 &client
->communication
.outbound
.payload
3656 if (status
== CLIENT_TRANSMISSION_STATUS_COMPLETE
) {
3657 client
->communication
.outbound
.queued_command_reply
= false;
3658 client
->communication
.outbound
.dropped_notification
= false;
3659 lttng_payload_clear(&client
->communication
.outbound
.payload
);
3664 return CLIENT_TRANSMISSION_STATUS_ERROR
;
3668 bool client_has_outbound_data_left(
3669 const struct notification_client
*client
)
3671 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3672 &client
->communication
.outbound
.payload
, 0, -1);
3673 const bool has_data
= pv
.buffer
.size
!= 0;
3674 const bool has_fds
= lttng_payload_view_get_fd_handle_count(&pv
);
3676 return has_data
|| has_fds
;
3679 /* Client lock must _not_ be held by the caller. */
3681 int client_send_command_reply(struct notification_client
*client
,
3682 struct notification_thread_state
*state
,
3683 enum lttng_notification_channel_status status
)
3686 struct lttng_notification_channel_command_reply reply
= {
3687 .status
= (int8_t) status
,
3689 struct lttng_notification_channel_message msg
= {
3690 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY
,
3691 .size
= sizeof(reply
),
3693 char buffer
[sizeof(msg
) + sizeof(reply
)];
3694 enum client_transmission_status transmission_status
;
3696 memcpy(buffer
, &msg
, sizeof(msg
));
3697 memcpy(buffer
+ sizeof(msg
), &reply
, sizeof(reply
));
3698 DBG("Send command reply (%i)", (int) status
);
3700 pthread_mutex_lock(&client
->lock
);
3701 if (client
->communication
.outbound
.queued_command_reply
) {
3702 /* Protocol error. */
3706 /* Enqueue buffer to outgoing queue and flush it. */
3707 ret
= lttng_dynamic_buffer_append(
3708 &client
->communication
.outbound
.payload
.buffer
,
3709 buffer
, sizeof(buffer
));
3714 transmission_status
= client_flush_outgoing_queue(client
);
3716 if (client_has_outbound_data_left(client
)) {
3717 /* Queue could not be emptied. */
3718 client
->communication
.outbound
.queued_command_reply
= true;
3721 pthread_mutex_unlock(&client
->lock
);
3722 ret
= client_handle_transmission_status(
3723 client
, transmission_status
, state
);
3730 pthread_mutex_unlock(&client
->lock
);
3736 int client_handle_message_unknown(struct notification_client
*client
,
3737 struct notification_thread_state
*state
)
3741 * Receiving message header. The function will be called again
3742 * once the rest of the message as been received and can be
3745 const struct lttng_notification_channel_message
*msg
;
3747 LTTNG_ASSERT(sizeof(*msg
) == client
->communication
.inbound
.payload
.buffer
.size
);
3748 msg
= (const struct lttng_notification_channel_message
*)
3749 client
->communication
.inbound
.payload
.buffer
.data
;
3751 if (msg
->size
== 0 ||
3752 msg
->size
> DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE
) {
3753 ERR("Invalid notification channel message: length = %u",
3759 switch (msg
->type
) {
3760 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3761 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3762 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3766 ERR("Invalid notification channel message: unexpected message type");
3770 client
->communication
.inbound
.bytes_to_receive
= msg
->size
;
3771 client
->communication
.inbound
.fds_to_receive
= msg
->fds
;
3772 client
->communication
.inbound
.msg_type
=
3773 (enum lttng_notification_channel_message_type
) msg
->type
;
3774 ret
= lttng_dynamic_buffer_set_size(
3775 &client
->communication
.inbound
.payload
.buffer
, msg
->size
);
3777 /* msg is not valid anymore due to lttng_dynamic_buffer_set_size. */
3784 int client_handle_message_handshake(struct notification_client
*client
,
3785 struct notification_thread_state
*state
)
3788 struct lttng_notification_channel_command_handshake
*handshake_client
;
3789 const struct lttng_notification_channel_command_handshake handshake_reply
= {
3790 .major
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
,
3791 .minor
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR
,
3793 const struct lttng_notification_channel_message msg_header
= {
3794 .type
= LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
,
3795 .size
= sizeof(handshake_reply
),
3797 enum lttng_notification_channel_status status
=
3798 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3799 char send_buffer
[sizeof(msg_header
) + sizeof(handshake_reply
)];
3801 memcpy(send_buffer
, &msg_header
, sizeof(msg_header
));
3802 memcpy(send_buffer
+ sizeof(msg_header
), &handshake_reply
,
3803 sizeof(handshake_reply
));
3806 (struct lttng_notification_channel_command_handshake
*)
3807 client
->communication
.inbound
.payload
.buffer
3809 client
->major
= handshake_client
->major
;
3810 client
->minor
= handshake_client
->minor
;
3811 if (!client
->communication
.inbound
.creds_received
) {
3812 ERR("No credentials received from client");
3817 client
->uid
= LTTNG_SOCK_GET_UID_CRED(
3818 &client
->communication
.inbound
.creds
);
3819 client
->gid
= LTTNG_SOCK_GET_GID_CRED(
3820 &client
->communication
.inbound
.creds
);
3821 client
->is_sessiond
= LTTNG_SOCK_GET_PID_CRED(&client
->communication
.inbound
.creds
) == getpid();
3822 DBG("Received handshake from client: uid = %u, gid = %u, protocol version = %i.%i, client is sessiond = %s",
3823 client
->uid
, client
->gid
, (int) client
->major
,
3824 (int) client
->minor
,
3825 client
->is_sessiond
? "true" : "false");
3827 if (handshake_client
->major
!=
3828 LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
) {
3829 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION
;
3832 pthread_mutex_lock(&client
->lock
);
3833 /* Outgoing queue will be flushed when the command reply is sent. */
3834 ret
= lttng_dynamic_buffer_append(
3835 &client
->communication
.outbound
.payload
.buffer
, send_buffer
,
3836 sizeof(send_buffer
));
3838 ERR("Failed to send protocol version to notification channel client");
3842 client
->validated
= true;
3843 client
->communication
.active
= true;
3844 pthread_mutex_unlock(&client
->lock
);
3846 /* Set reception state to receive the next message header. */
3847 ret
= client_reset_inbound_state(client
);
3849 ERR("Failed to reset client communication's inbound state");
3853 /* Flushes the outgoing queue. */
3854 ret
= client_send_command_reply(client
, state
, status
);
3856 ERR("Failed to send reply to notification channel client");
3862 pthread_mutex_unlock(&client
->lock
);
3868 int client_handle_message_subscription(
3869 struct notification_client
*client
,
3870 enum lttng_notification_channel_message_type msg_type
,
3871 struct notification_thread_state
*state
)
3874 struct lttng_condition
*condition
;
3875 enum lttng_notification_channel_status status
=
3876 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3877 struct lttng_payload_view condition_view
=
3878 lttng_payload_view_from_payload(
3879 &client
->communication
.inbound
.payload
,
3881 size_t expected_condition_size
;
3884 * No need to lock client to sample the inbound state as the only
3885 * other thread accessing clients (action executor) only uses the
3888 expected_condition_size
= client
->communication
.inbound
.payload
.buffer
.size
;
3889 ret
= lttng_condition_create_from_payload(&condition_view
, &condition
);
3890 if (ret
!= expected_condition_size
) {
3891 ERR("Malformed condition received from client");
3895 /* Ownership of condition is always transferred. */
3896 if (msg_type
== LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
) {
3897 ret
= notification_thread_client_subscribe(
3898 client
, condition
, state
, &status
);
3900 ret
= notification_thread_client_unsubscribe(
3901 client
, condition
, state
, &status
);
3908 /* Set reception state to receive the next message header. */
3909 ret
= client_reset_inbound_state(client
);
3911 ERR("Failed to reset client communication's inbound state");
3915 ret
= client_send_command_reply(client
, state
, status
);
3917 ERR("Failed to send reply to notification channel client");
3926 int client_dispatch_message(struct notification_client
*client
,
3927 struct notification_thread_state
*state
)
3931 if (client
->communication
.inbound
.msg_type
!=
3932 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
&&
3933 client
->communication
.inbound
.msg_type
!=
3934 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
&&
3935 !client
->validated
) {
3936 WARN("client attempted a command before handshake");
3941 switch (client
->communication
.inbound
.msg_type
) {
3942 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
:
3944 ret
= client_handle_message_unknown(client
, state
);
3947 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3949 ret
= client_handle_message_handshake(client
, state
);
3952 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3953 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3955 ret
= client_handle_message_subscription(client
,
3956 client
->communication
.inbound
.msg_type
, state
);
3966 /* Incoming data from client. */
3967 int handle_notification_thread_client_in(
3968 struct notification_thread_state
*state
, int socket
)
3971 struct notification_client
*client
;
3976 client
= get_client_from_socket(socket
, state
);
3978 /* Internal error, abort. */
3983 if (client
->communication
.inbound
.bytes_to_receive
== 0 &&
3984 client
->communication
.inbound
.fds_to_receive
!= 0) {
3985 /* Only FDs left to receive. */
3989 offset
= client
->communication
.inbound
.payload
.buffer
.size
-
3990 client
->communication
.inbound
.bytes_to_receive
;
3991 if (client
->communication
.inbound
.expect_creds
) {
3992 recv_ret
= lttcomm_recv_creds_unix_sock(socket
,
3993 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
3994 client
->communication
.inbound
.bytes_to_receive
,
3995 &client
->communication
.inbound
.creds
);
3997 client
->communication
.inbound
.expect_creds
= false;
3998 client
->communication
.inbound
.creds_received
= true;
4001 recv_ret
= lttcomm_recv_unix_sock_non_block(socket
,
4002 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
4003 client
->communication
.inbound
.bytes_to_receive
);
4005 if (recv_ret
>= 0) {
4006 client
->communication
.inbound
.bytes_to_receive
-= recv_ret
;
4008 goto error_disconnect_client
;
4011 if (client
->communication
.inbound
.bytes_to_receive
!= 0) {
4012 /* Message incomplete wait for more data. */
4018 LTTNG_ASSERT(client
->communication
.inbound
.bytes_to_receive
== 0);
4021 if (client
->communication
.inbound
.fds_to_receive
!= 0) {
4022 ret
= lttcomm_recv_payload_fds_unix_sock_non_block(
4024 client
->communication
.inbound
.fds_to_receive
,
4025 &client
->communication
.inbound
.payload
);
4028 * Fds received. non blocking fds passing is all
4031 ssize_t expected_size
;
4033 expected_size
= sizeof(int) *
4034 client
->communication
.inbound
4036 LTTNG_ASSERT(ret
== expected_size
);
4037 client
->communication
.inbound
.fds_to_receive
= 0;
4038 } else if (ret
== 0) {
4039 /* Received nothing. */
4043 goto error_disconnect_client
;
4047 /* At this point the message is complete.*/
4048 LTTNG_ASSERT(client
->communication
.inbound
.bytes_to_receive
== 0 &&
4049 client
->communication
.inbound
.fds_to_receive
== 0);
4050 ret
= client_dispatch_message(client
, state
);
4053 * Only returns an error if this client must be
4056 goto error_disconnect_client
;
4063 error_disconnect_client
:
4064 ret
= notification_thread_client_disconnect(client
, state
);
4068 /* Client ready to receive outgoing data. */
4069 int handle_notification_thread_client_out(
4070 struct notification_thread_state
*state
, int socket
)
4073 struct notification_client
*client
;
4074 enum client_transmission_status transmission_status
;
4077 client
= get_client_from_socket(socket
, state
);
4079 /* Internal error, abort. */
4084 pthread_mutex_lock(&client
->lock
);
4085 transmission_status
= client_flush_outgoing_queue(client
);
4086 pthread_mutex_unlock(&client
->lock
);
4088 ret
= client_handle_transmission_status(
4089 client
, transmission_status
, state
);
4099 bool evaluate_buffer_usage_condition(const struct lttng_condition
*condition
,
4100 const struct channel_state_sample
*sample
,
4101 uint64_t buffer_capacity
)
4103 bool result
= false;
4105 enum lttng_condition_type condition_type
;
4106 const struct lttng_condition_buffer_usage
*use_condition
= container_of(
4107 condition
, struct lttng_condition_buffer_usage
,
4110 if (use_condition
->threshold_bytes
.set
) {
4111 threshold
= use_condition
->threshold_bytes
.value
;
4114 * Threshold was expressed as a ratio.
4116 * TODO the threshold (in bytes) of conditions expressed
4117 * as a ratio of total buffer size could be cached to
4118 * forego this double-multiplication or it could be performed
4119 * as fixed-point math.
4121 * Note that caching should accommodates the case where the
4122 * condition applies to multiple channels (i.e. don't assume
4123 * that all channels matching my_chann* have the same size...)
4125 threshold
= (uint64_t) (use_condition
->threshold_ratio
.value
*
4126 (double) buffer_capacity
);
4129 condition_type
= lttng_condition_get_type(condition
);
4130 if (condition_type
== LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
) {
4131 DBG("Low buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4132 threshold
, sample
->highest_usage
);
4135 * The low condition should only be triggered once _all_ of the
4136 * streams in a channel have gone below the "low" threshold.
4138 if (sample
->highest_usage
<= threshold
) {
4142 DBG("High buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4143 threshold
, sample
->highest_usage
);
4146 * For high buffer usage scenarios, we want to trigger whenever
4147 * _any_ of the streams has reached the "high" threshold.
4149 if (sample
->highest_usage
>= threshold
) {
4158 bool evaluate_session_consumed_size_condition(
4159 const struct lttng_condition
*condition
,
4160 uint64_t session_consumed_size
)
4163 const struct lttng_condition_session_consumed_size
*size_condition
=
4164 container_of(condition
,
4165 struct lttng_condition_session_consumed_size
,
4168 threshold
= size_condition
->consumed_threshold_bytes
.value
;
4169 DBG("Session consumed size condition being evaluated: threshold = %" PRIu64
", current size = %" PRIu64
,
4170 threshold
, session_consumed_size
);
4171 return session_consumed_size
>= threshold
;
4175 int evaluate_buffer_condition(const struct lttng_condition
*condition
,
4176 struct lttng_evaluation
**evaluation
,
4177 const struct notification_thread_state
*state
,
4178 const struct channel_state_sample
*previous_sample
,
4179 const struct channel_state_sample
*latest_sample
,
4180 uint64_t previous_session_consumed_total
,
4181 uint64_t latest_session_consumed_total
,
4182 struct channel_info
*channel_info
)
4185 enum lttng_condition_type condition_type
;
4186 const bool previous_sample_available
= !!previous_sample
;
4187 bool previous_sample_result
= false;
4188 bool latest_sample_result
;
4190 condition_type
= lttng_condition_get_type(condition
);
4192 switch (condition_type
) {
4193 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4194 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4195 if (caa_likely(previous_sample_available
)) {
4196 previous_sample_result
=
4197 evaluate_buffer_usage_condition(condition
,
4198 previous_sample
, channel_info
->capacity
);
4200 latest_sample_result
= evaluate_buffer_usage_condition(
4201 condition
, latest_sample
,
4202 channel_info
->capacity
);
4204 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
4205 if (caa_likely(previous_sample_available
)) {
4206 previous_sample_result
=
4207 evaluate_session_consumed_size_condition(
4209 previous_session_consumed_total
);
4211 latest_sample_result
=
4212 evaluate_session_consumed_size_condition(
4214 latest_session_consumed_total
);
4217 /* Unknown condition type; internal error. */
4221 if (!latest_sample_result
||
4222 (previous_sample_result
== latest_sample_result
)) {
4224 * Only trigger on a condition evaluation transition.
4226 * NOTE: This edge-triggered logic may not be appropriate for
4227 * future condition types.
4232 if (!evaluation
|| !latest_sample_result
) {
4236 switch (condition_type
) {
4237 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4238 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4239 *evaluation
= lttng_evaluation_buffer_usage_create(
4241 latest_sample
->highest_usage
,
4242 channel_info
->capacity
);
4244 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
4245 *evaluation
= lttng_evaluation_session_consumed_size_create(
4246 latest_session_consumed_total
);
4261 int client_notification_overflow(struct notification_client
*client
)
4264 const struct lttng_notification_channel_message msg
= {
4265 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED
,
4268 ASSERT_LOCKED(client
->lock
);
4270 DBG("Dropping notification addressed to client (socket fd = %i)",
4272 if (client
->communication
.outbound
.dropped_notification
) {
4274 * The client already has a "notification dropped" message
4275 * in its outgoing queue. Nothing to do since all
4276 * of those messages are coalesced.
4281 client
->communication
.outbound
.dropped_notification
= true;
4282 ret
= lttng_dynamic_buffer_append(
4283 &client
->communication
.outbound
.payload
.buffer
, &msg
,
4286 PERROR("Failed to enqueue \"dropped notification\" message in client's (socket fd = %i) outgoing queue",
4293 static int client_handle_transmission_status_wrapper(
4294 struct notification_client
*client
,
4295 enum client_transmission_status status
,
4298 return client_handle_transmission_status(client
, status
,
4299 (struct notification_thread_state
*) user_data
);
4303 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
4304 const struct lttng_evaluation
*evaluation
,
4305 struct notification_client_list
* client_list
,
4306 struct notification_thread_state
*state
,
4307 uid_t object_uid
, gid_t object_gid
)
4309 const struct lttng_credentials creds
= {
4310 .uid
= LTTNG_OPTIONAL_INIT_VALUE(object_uid
),
4311 .gid
= LTTNG_OPTIONAL_INIT_VALUE(object_gid
),
4314 return notification_client_list_send_evaluation(client_list
,
4315 trigger
, evaluation
,
4317 client_handle_transmission_status_wrapper
, state
);
4321 * Permission checks relative to notification channel clients are performed
4322 * here. Notice how object, client, and trigger credentials are involved in
4325 * The `object` credentials are the credentials associated with the "subject"
4326 * of a condition. For instance, a `rotation completed` condition applies
4327 * to a session. When that condition is met, it will produce an evaluation
4328 * against a session. Hence, in this case, the `object` credentials are the
4329 * credentials of the "subject" session.
4331 * The `trigger` credentials are the credentials of the user that registered the
4334 * The `client` credentials are the credentials of the user that created a given
4335 * notification channel.
4337 * In terms of visibility, it is expected that non-privilieged users can only
4338 * register triggers against "their" objects (their own sessions and
4339 * applications they are allowed to interact with). They can then open a
4340 * notification channel and subscribe to notifications associated with those
4343 * As for privilieged users, they can register triggers against the objects of
4344 * other users. They can then subscribe to the notifications associated to their
4345 * triggers. Privilieged users _can't_ subscribe to the notifications of
4346 * triggers owned by other users; they must create their own triggers.
4348 * This is more a concern of usability than security. It would be difficult for
4349 * a root user reliably subscribe to a specific set of conditions without
4350 * interference from external users (those could, for instance, unregister
4353 int notification_client_list_send_evaluation(
4354 struct notification_client_list
*client_list
,
4355 const struct lttng_trigger
*trigger
,
4356 const struct lttng_evaluation
*evaluation
,
4357 const struct lttng_credentials
*source_object_creds
,
4358 report_client_transmission_result_cb client_report
,
4362 struct lttng_payload msg_payload
;
4363 struct notification_client_list_element
*client_list_element
, *tmp
;
4364 const struct lttng_notification notification
= {
4365 .trigger
= (struct lttng_trigger
*) trigger
,
4366 .evaluation
= (struct lttng_evaluation
*) evaluation
,
4368 struct lttng_notification_channel_message msg_header
= {
4369 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION
,
4371 const struct lttng_credentials
*trigger_creds
=
4372 lttng_trigger_get_credentials(trigger
);
4374 lttng_payload_init(&msg_payload
);
4376 ret
= lttng_dynamic_buffer_append(&msg_payload
.buffer
, &msg_header
,
4377 sizeof(msg_header
));
4382 ret
= lttng_notification_serialize(¬ification
, &msg_payload
);
4384 ERR("Failed to serialize notification");
4389 /* Update payload size. */
4390 ((struct lttng_notification_channel_message
*) msg_payload
.buffer
.data
)
4391 ->size
= (uint32_t)(
4392 msg_payload
.buffer
.size
- sizeof(msg_header
));
4394 /* Update the payload number of fds. */
4396 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
4397 &msg_payload
, 0, -1);
4399 ((struct lttng_notification_channel_message
*)
4400 msg_payload
.buffer
.data
)->fds
= (uint32_t)
4401 lttng_payload_view_get_fd_handle_count(&pv
);
4404 pthread_mutex_lock(&client_list
->lock
);
4405 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4406 &client_list
->clients_list
, node
) {
4407 enum client_transmission_status transmission_status
;
4408 struct notification_client
*client
=
4409 client_list_element
->client
;
4412 pthread_mutex_lock(&client
->lock
);
4413 if (!client
->communication
.active
) {
4415 * Skip inactive client (protocol error or
4418 DBG("Skipping client at it is marked as inactive");
4422 if (lttng_trigger_is_hidden(trigger
) && !client
->is_sessiond
) {
4424 * Notifications resulting from an hidden trigger are
4425 * only sent to the session daemon.
4427 DBG("Skipping client as the trigger is hidden and the client is not the session daemon");
4431 if (source_object_creds
) {
4432 if (client
->uid
!= lttng_credentials_get_uid(source_object_creds
) &&
4433 client
->gid
!= lttng_credentials_get_gid(source_object_creds
) &&
4436 * Client is not allowed to monitor this
4439 DBG("Skipping client at it does not have the object permission to receive notification for this trigger");
4444 if (client
->uid
!= lttng_credentials_get_uid(trigger_creds
)) {
4445 DBG("Skipping client at it does not have the permission to receive notification for this trigger");
4449 DBG("Sending notification to client (fd = %i, %zu bytes)",
4450 client
->socket
, msg_payload
.buffer
.size
);
4452 if (client_has_outbound_data_left(client
)) {
4454 * Outgoing data is already buffered for this client;
4455 * drop the notification and enqueue a "dropped
4456 * notification" message if this is the first dropped
4457 * notification since the socket spilled-over to the
4460 ret
= client_notification_overflow(client
);
4467 ret
= lttng_payload_copy(&msg_payload
, &client
->communication
.outbound
.payload
);
4473 transmission_status
= client_flush_outgoing_queue(client
);
4474 pthread_mutex_unlock(&client
->lock
);
4475 ret
= client_report(client
, transmission_status
, user_data
);
4478 goto end_unlock_list
;
4484 pthread_mutex_unlock(&client
->lock
);
4487 goto end_unlock_list
;
4493 pthread_mutex_unlock(&client_list
->lock
);
4495 lttng_payload_reset(&msg_payload
);
4500 struct lttng_event_notifier_notification
*recv_one_event_notifier_notification(
4501 int notification_pipe_read_fd
, enum lttng_domain_type domain
)
4505 struct lttng_event_notifier_notification
*notification
= NULL
;
4506 char *capture_buffer
= NULL
;
4507 size_t capture_buffer_size
;
4508 void *reception_buffer
;
4509 size_t reception_size
;
4511 struct lttng_ust_abi_event_notifier_notification ust_notification
;
4512 struct lttng_kernel_abi_event_notifier_notification kernel_notification
;
4514 /* Init lttng_event_notifier_notification */
4516 case LTTNG_DOMAIN_UST
:
4517 reception_buffer
= (void *) &ust_notification
;
4518 reception_size
= sizeof(ust_notification
);
4520 case LTTNG_DOMAIN_KERNEL
:
4521 reception_buffer
= (void *) &kernel_notification
;
4522 reception_size
= sizeof(kernel_notification
);
4529 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4530 * ensuring that read/write of tracer notifications are atomic.
4532 ret
= lttng_read(notification_pipe_read_fd
, reception_buffer
,
4534 if (ret
!= reception_size
) {
4535 PERROR("Failed to read from event source notification pipe: fd = %d, size to read = %zu, ret = %d",
4536 notification_pipe_read_fd
, reception_size
, ret
);
4542 case LTTNG_DOMAIN_UST
:
4543 token
= ust_notification
.token
;
4544 capture_buffer_size
= ust_notification
.capture_buf_size
;
4546 case LTTNG_DOMAIN_KERNEL
:
4547 token
= kernel_notification
.token
;
4548 capture_buffer_size
= kernel_notification
.capture_buf_size
;
4554 if (capture_buffer_size
== 0) {
4555 capture_buffer
= NULL
;
4559 if (capture_buffer_size
> MAX_CAPTURE_SIZE
) {
4560 ERR("Event notifier has a capture payload size which exceeds the maximum allowed size: capture_payload_size = %zu bytes, max allowed size = %d bytes",
4561 capture_buffer_size
, MAX_CAPTURE_SIZE
);
4565 capture_buffer
= zmalloc(capture_buffer_size
);
4566 if (!capture_buffer
) {
4567 ERR("Failed to allocate capture buffer");
4571 /* Fetch additional payload (capture). */
4572 ret
= lttng_read(notification_pipe_read_fd
, capture_buffer
, capture_buffer_size
);
4573 if (ret
!= capture_buffer_size
) {
4574 ERR("Failed to read from event source pipe (fd = %i)",
4575 notification_pipe_read_fd
);
4580 notification
= lttng_event_notifier_notification_create(token
, domain
,
4581 capture_buffer
, capture_buffer_size
);
4582 if (notification
== NULL
) {
4587 * Ownership transfered to the lttng_event_notifier_notification object.
4589 capture_buffer
= NULL
;
4592 free(capture_buffer
);
4593 return notification
;
4597 int dispatch_one_event_notifier_notification(struct notification_thread_state
*state
,
4598 struct lttng_event_notifier_notification
*notification
)
4600 struct cds_lfht_node
*node
;
4601 struct cds_lfht_iter iter
;
4602 struct notification_trigger_tokens_ht_element
*element
;
4603 struct lttng_evaluation
*evaluation
= NULL
;
4604 enum action_executor_status executor_status
;
4605 struct notification_client_list
*client_list
= NULL
;
4607 unsigned int capture_count
= 0;
4609 /* Find triggers associated with this token. */
4611 cds_lfht_lookup(state
->trigger_tokens_ht
,
4612 hash_key_u64(¬ification
->tracer_token
, lttng_ht_seed
),
4613 match_trigger_token
, ¬ification
->tracer_token
, &iter
);
4614 node
= cds_lfht_iter_get_node(&iter
);
4615 if (caa_unlikely(!node
)) {
4617 * This is not an error, slow consumption of the tracer
4618 * notifications can lead to situations where a trigger is
4619 * removed but we still get tracer notifications matching a
4620 * trigger that no longer exists.
4626 element
= caa_container_of(node
,
4627 struct notification_trigger_tokens_ht_element
,
4630 if (lttng_condition_event_rule_matches_get_capture_descriptor_count(
4631 lttng_trigger_get_const_condition(element
->trigger
),
4632 &capture_count
) != LTTNG_CONDITION_STATUS_OK
) {
4633 ERR("Failed to get capture count");
4638 if (!notification
->capture_buffer
&& capture_count
!= 0) {
4639 ERR("Expected capture but capture buffer is null");
4644 evaluation
= lttng_evaluation_event_rule_matches_create(
4645 container_of(lttng_trigger_get_const_condition(
4647 struct lttng_condition_event_rule_matches
,
4649 notification
->capture_buffer
,
4650 notification
->capture_buf_size
, false);
4652 if (evaluation
== NULL
) {
4653 ERR("Failed to create event rule matches evaluation while creating and enqueuing action executor job");
4658 client_list
= get_client_list_from_condition(state
,
4659 lttng_trigger_get_const_condition(element
->trigger
));
4660 executor_status
= action_executor_enqueue_trigger(state
->executor
,
4661 element
->trigger
, evaluation
, NULL
, client_list
);
4662 switch (executor_status
) {
4663 case ACTION_EXECUTOR_STATUS_OK
:
4666 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4668 struct notification_client_list_element
*client_list_element
,
4672 * Not a fatal error; this is expected and simply means the
4673 * executor has too much work queued already.
4677 /* No clients subscribed to notifications for this trigger. */
4682 /* Warn clients that a notification (or more) was dropped. */
4683 pthread_mutex_lock(&client_list
->lock
);
4684 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4685 &client_list
->clients_list
, node
) {
4686 enum client_transmission_status transmission_status
;
4687 struct notification_client
*client
=
4688 client_list_element
->client
;
4690 pthread_mutex_lock(&client
->lock
);
4691 ret
= client_notification_overflow(client
);
4697 transmission_status
=
4698 client_flush_outgoing_queue(client
);
4699 ret
= client_handle_transmission_status(
4700 client
, transmission_status
, state
);
4706 pthread_mutex_unlock(&client
->lock
);
4712 pthread_mutex_unlock(&client_list
->lock
);
4715 case ACTION_EXECUTOR_STATUS_INVALID
:
4716 case ACTION_EXECUTOR_STATUS_ERROR
:
4717 /* Fatal error, shut down everything. */
4718 ERR("Fatal error encoutered while enqueuing action to the action executor");
4722 /* Unhandled error. */
4727 notification_client_list_put(client_list
);
4734 int handle_one_event_notifier_notification(
4735 struct notification_thread_state
*state
,
4736 int pipe
, enum lttng_domain_type domain
)
4739 struct lttng_event_notifier_notification
*notification
= NULL
;
4741 notification
= recv_one_event_notifier_notification(pipe
, domain
);
4742 if (notification
== NULL
) {
4743 /* Reception failed, don't consider it fatal. */
4744 ERR("Error receiving an event notifier notification from tracer: fd = %i, domain = %s",
4745 pipe
, lttng_domain_type_str(domain
));
4749 ret
= dispatch_one_event_notifier_notification(state
, notification
);
4751 ERR("Error dispatching an event notifier notification from tracer: fd = %i, domain = %s",
4752 pipe
, lttng_domain_type_str(domain
));
4757 lttng_event_notifier_notification_destroy(notification
);
4761 int handle_notification_thread_event_notification(struct notification_thread_state
*state
,
4762 int pipe
, enum lttng_domain_type domain
)
4764 return handle_one_event_notifier_notification(state
, pipe
, domain
);
4767 int handle_notification_thread_channel_sample(
4768 struct notification_thread_state
*state
, int pipe
,
4769 enum lttng_domain_type domain
)
4772 struct lttcomm_consumer_channel_monitor_msg sample_msg
;
4773 struct channel_info
*channel_info
;
4774 struct cds_lfht_node
*node
;
4775 struct cds_lfht_iter iter
;
4776 struct lttng_channel_trigger_list
*trigger_list
;
4777 struct lttng_trigger_list_element
*trigger_list_element
;
4778 bool previous_sample_available
= false;
4779 struct channel_state_sample previous_sample
, latest_sample
;
4780 uint64_t previous_session_consumed_total
, latest_session_consumed_total
;
4781 struct lttng_credentials channel_creds
;
4784 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4785 * ensuring that read/write of sampling messages are atomic.
4787 ret
= lttng_read(pipe
, &sample_msg
, sizeof(sample_msg
));
4788 if (ret
!= sizeof(sample_msg
)) {
4789 ERR("Failed to read from monitoring pipe (fd = %i)",
4796 latest_sample
.key
.key
= sample_msg
.key
;
4797 latest_sample
.key
.domain
= domain
;
4798 latest_sample
.highest_usage
= sample_msg
.highest
;
4799 latest_sample
.lowest_usage
= sample_msg
.lowest
;
4800 latest_sample
.channel_total_consumed
= sample_msg
.total_consumed
;
4804 /* Retrieve the channel's informations */
4805 cds_lfht_lookup(state
->channels_ht
,
4806 hash_channel_key(&latest_sample
.key
),
4810 node
= cds_lfht_iter_get_node(&iter
);
4811 if (caa_unlikely(!node
)) {
4813 * Not an error since the consumer can push a sample to the pipe
4814 * and the rest of the session daemon could notify us of the
4815 * channel's destruction before we get a chance to process that
4818 DBG("Received a sample for an unknown channel from consumerd, key = %" PRIu64
" in %s domain",
4819 latest_sample
.key
.key
,
4820 lttng_domain_type_str(domain
));
4823 channel_info
= caa_container_of(node
, struct channel_info
,
4825 DBG("Handling channel sample for channel %s (key = %" PRIu64
") in session %s (highest usage = %" PRIu64
", lowest usage = %" PRIu64
", total consumed = %" PRIu64
")",
4827 latest_sample
.key
.key
,
4828 channel_info
->session_info
->name
,
4829 latest_sample
.highest_usage
,
4830 latest_sample
.lowest_usage
,
4831 latest_sample
.channel_total_consumed
);
4833 previous_session_consumed_total
=
4834 channel_info
->session_info
->consumed_data_size
;
4836 /* Retrieve the channel's last sample, if it exists, and update it. */
4837 cds_lfht_lookup(state
->channel_state_ht
,
4838 hash_channel_key(&latest_sample
.key
),
4839 match_channel_state_sample
,
4842 node
= cds_lfht_iter_get_node(&iter
);
4843 if (caa_likely(node
)) {
4844 struct channel_state_sample
*stored_sample
;
4846 /* Update the sample stored. */
4847 stored_sample
= caa_container_of(node
,
4848 struct channel_state_sample
,
4849 channel_state_ht_node
);
4851 memcpy(&previous_sample
, stored_sample
,
4852 sizeof(previous_sample
));
4853 stored_sample
->highest_usage
= latest_sample
.highest_usage
;
4854 stored_sample
->lowest_usage
= latest_sample
.lowest_usage
;
4855 stored_sample
->channel_total_consumed
= latest_sample
.channel_total_consumed
;
4856 previous_sample_available
= true;
4858 latest_session_consumed_total
=
4859 previous_session_consumed_total
+
4860 (latest_sample
.channel_total_consumed
- previous_sample
.channel_total_consumed
);
4863 * This is the channel's first sample, allocate space for and
4864 * store the new sample.
4866 struct channel_state_sample
*stored_sample
;
4868 stored_sample
= zmalloc(sizeof(*stored_sample
));
4869 if (!stored_sample
) {
4874 memcpy(stored_sample
, &latest_sample
, sizeof(*stored_sample
));
4875 cds_lfht_node_init(&stored_sample
->channel_state_ht_node
);
4876 cds_lfht_add(state
->channel_state_ht
,
4877 hash_channel_key(&stored_sample
->key
),
4878 &stored_sample
->channel_state_ht_node
);
4880 latest_session_consumed_total
=
4881 previous_session_consumed_total
+
4882 latest_sample
.channel_total_consumed
;
4885 channel_info
->session_info
->consumed_data_size
=
4886 latest_session_consumed_total
;
4888 /* Find triggers associated with this channel. */
4889 cds_lfht_lookup(state
->channel_triggers_ht
,
4890 hash_channel_key(&latest_sample
.key
),
4891 match_channel_trigger_list
,
4894 node
= cds_lfht_iter_get_node(&iter
);
4895 if (caa_likely(!node
)) {
4899 channel_creds
= (typeof(channel_creds
)) {
4900 .uid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->uid
),
4901 .gid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->gid
),
4904 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
4905 channel_triggers_ht_node
);
4906 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
4908 const struct lttng_condition
*condition
;
4909 struct lttng_trigger
*trigger
;
4910 struct notification_client_list
*client_list
= NULL
;
4911 struct lttng_evaluation
*evaluation
= NULL
;
4912 enum action_executor_status executor_status
;
4915 trigger
= trigger_list_element
->trigger
;
4916 condition
= lttng_trigger_get_const_condition(trigger
);
4917 LTTNG_ASSERT(condition
);
4920 * Check if any client is subscribed to the result of this
4923 client_list
= get_client_list_from_condition(state
, condition
);
4925 ret
= evaluate_buffer_condition(condition
, &evaluation
, state
,
4926 previous_sample_available
? &previous_sample
: NULL
,
4928 previous_session_consumed_total
,
4929 latest_session_consumed_total
,
4931 if (caa_unlikely(ret
)) {
4935 if (caa_likely(!evaluation
)) {
4940 * Ownership of `evaluation` transferred to the action executor
4941 * no matter the result.
4943 executor_status
= action_executor_enqueue_trigger(
4944 state
->executor
, trigger
, evaluation
,
4945 &channel_creds
, client_list
);
4947 switch (executor_status
) {
4948 case ACTION_EXECUTOR_STATUS_OK
:
4950 case ACTION_EXECUTOR_STATUS_ERROR
:
4951 case ACTION_EXECUTOR_STATUS_INVALID
:
4953 * TODO Add trigger identification (name/id) when
4954 * it is added to the API.
4956 ERR("Fatal error occurred while enqueuing action associated with buffer-condition trigger");
4959 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4961 * TODO Add trigger identification (name/id) when
4962 * it is added to the API.
4964 * Not a fatal error.
4966 WARN("No space left when enqueuing action associated with buffer-condition trigger");
4974 notification_client_list_put(client_list
);
4975 if (caa_unlikely(ret
)) {