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
= (uint64_t *) 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
= (const char *) 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
= (struct 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
= (struct 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
= (struct 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
= (notification_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
= (notification_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
= (lttng_condition_list_element
*) zmalloc(sizeof(*condition_list_element
));
1120 if (!condition_list_element
) {
1124 client_list_element
= (notification_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 ASSERT_RCU_READ_LOCKED();
1318 cds_lfht_lookup(state
->client_socket_ht
,
1319 hash_client_socket(socket
),
1320 match_client_socket
,
1321 (void *) (unsigned long) socket
,
1323 node
= cds_lfht_iter_get_node(&iter
);
1328 client
= caa_container_of(node
, struct notification_client
,
1329 client_socket_ht_node
);
1335 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1339 struct notification_client
*get_client_from_id(notification_client_id id
,
1340 struct notification_thread_state
*state
)
1342 struct cds_lfht_iter iter
;
1343 struct cds_lfht_node
*node
;
1344 struct notification_client
*client
= NULL
;
1346 ASSERT_RCU_READ_LOCKED();
1348 cds_lfht_lookup(state
->client_id_ht
,
1353 node
= cds_lfht_iter_get_node(&iter
);
1358 client
= caa_container_of(node
, struct notification_client
,
1365 bool buffer_usage_condition_applies_to_channel(
1366 const struct lttng_condition
*condition
,
1367 const struct channel_info
*channel_info
)
1369 enum lttng_condition_status status
;
1370 enum lttng_domain_type condition_domain
;
1371 const char *condition_session_name
= NULL
;
1372 const char *condition_channel_name
= NULL
;
1374 status
= lttng_condition_buffer_usage_get_domain_type(condition
,
1376 LTTNG_ASSERT(status
== LTTNG_CONDITION_STATUS_OK
);
1377 if (channel_info
->key
.domain
!= condition_domain
) {
1381 status
= lttng_condition_buffer_usage_get_session_name(
1382 condition
, &condition_session_name
);
1383 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1385 status
= lttng_condition_buffer_usage_get_channel_name(
1386 condition
, &condition_channel_name
);
1387 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_channel_name
);
1389 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1392 if (strcmp(channel_info
->name
, condition_channel_name
)) {
1402 bool session_consumed_size_condition_applies_to_channel(
1403 const struct lttng_condition
*condition
,
1404 const struct channel_info
*channel_info
)
1406 enum lttng_condition_status status
;
1407 const char *condition_session_name
= NULL
;
1409 status
= lttng_condition_session_consumed_size_get_session_name(
1410 condition
, &condition_session_name
);
1411 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1413 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1423 bool trigger_applies_to_channel(const struct lttng_trigger
*trigger
,
1424 const struct channel_info
*channel_info
)
1426 const struct lttng_condition
*condition
;
1427 bool trigger_applies
;
1429 condition
= lttng_trigger_get_const_condition(trigger
);
1434 switch (lttng_condition_get_type(condition
)) {
1435 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
1436 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
1437 trigger_applies
= buffer_usage_condition_applies_to_channel(
1438 condition
, channel_info
);
1440 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
1441 trigger_applies
= session_consumed_size_condition_applies_to_channel(
1442 condition
, channel_info
);
1448 return trigger_applies
;
1453 /* Must be called with RCU read lock held. */
1455 struct lttng_session_trigger_list
*get_session_trigger_list(
1456 struct notification_thread_state
*state
,
1457 const char *session_name
)
1459 struct lttng_session_trigger_list
*list
= NULL
;
1460 struct cds_lfht_node
*node
;
1461 struct cds_lfht_iter iter
;
1463 ASSERT_RCU_READ_LOCKED();
1465 cds_lfht_lookup(state
->session_triggers_ht
,
1466 hash_key_str(session_name
, lttng_ht_seed
),
1467 match_session_trigger_list
,
1470 node
= cds_lfht_iter_get_node(&iter
);
1473 * Not an error, the list of triggers applying to that session
1474 * will be initialized when the session is created.
1476 DBG("No trigger list found for session \"%s\" as it is not yet known to the notification system",
1481 list
= caa_container_of(node
,
1482 struct lttng_session_trigger_list
,
1483 session_triggers_ht_node
);
1489 * Allocate an empty lttng_session_trigger_list for the session named
1492 * No ownership of 'session_name' is assumed by the session trigger list.
1493 * It is the caller's responsability to ensure the session name is alive
1494 * for as long as this list is.
1497 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
1498 const char *session_name
,
1499 struct cds_lfht
*session_triggers_ht
)
1501 struct lttng_session_trigger_list
*list
;
1503 list
= (lttng_session_trigger_list
*) zmalloc(sizeof(*list
));
1507 list
->session_name
= session_name
;
1508 CDS_INIT_LIST_HEAD(&list
->list
);
1509 cds_lfht_node_init(&list
->session_triggers_ht_node
);
1510 list
->session_triggers_ht
= session_triggers_ht
;
1513 /* Publish the list through the session_triggers_ht. */
1514 cds_lfht_add(session_triggers_ht
,
1515 hash_key_str(session_name
, lttng_ht_seed
),
1516 &list
->session_triggers_ht_node
);
1523 void free_session_trigger_list_rcu(struct rcu_head
*node
)
1525 free(caa_container_of(node
, struct lttng_session_trigger_list
,
1530 void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list
*list
)
1532 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1534 /* Empty the list element by element, and then free the list itself. */
1535 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1536 &list
->list
, node
) {
1537 cds_list_del(&trigger_list_element
->node
);
1538 free(trigger_list_element
);
1541 /* Unpublish the list from the session_triggers_ht. */
1542 cds_lfht_del(list
->session_triggers_ht
,
1543 &list
->session_triggers_ht_node
);
1545 call_rcu(&list
->rcu_node
, free_session_trigger_list_rcu
);
1549 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
1550 struct lttng_trigger
*trigger
)
1553 struct lttng_trigger_list_element
*new_element
=
1554 (lttng_trigger_list_element
*) zmalloc(sizeof(*new_element
));
1560 CDS_INIT_LIST_HEAD(&new_element
->node
);
1561 new_element
->trigger
= trigger
;
1562 cds_list_add(&new_element
->node
, &list
->list
);
1568 bool trigger_applies_to_session(const struct lttng_trigger
*trigger
,
1569 const char *session_name
)
1571 bool applies
= false;
1572 const struct lttng_condition
*condition
;
1574 condition
= lttng_trigger_get_const_condition(trigger
);
1575 switch (lttng_condition_get_type(condition
)) {
1576 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1577 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1579 enum lttng_condition_status condition_status
;
1580 const char *condition_session_name
;
1582 condition_status
= lttng_condition_session_rotation_get_session_name(
1583 condition
, &condition_session_name
);
1584 if (condition_status
!= LTTNG_CONDITION_STATUS_OK
) {
1585 ERR("Failed to retrieve session rotation condition's session name");
1589 LTTNG_ASSERT(condition_session_name
);
1590 applies
= !strcmp(condition_session_name
, session_name
);
1601 * Allocate and initialize an lttng_session_trigger_list which contains
1602 * all triggers that apply to the session named 'session_name'.
1604 * No ownership of 'session_name' is assumed by the session trigger list.
1605 * It is the caller's responsability to ensure the session name is alive
1606 * for as long as this list is.
1609 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
1610 const struct notification_thread_state
*state
,
1611 const char *session_name
)
1613 int trigger_count
= 0;
1614 struct lttng_session_trigger_list
*session_trigger_list
= NULL
;
1615 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1616 struct cds_lfht_iter iter
;
1618 session_trigger_list
= lttng_session_trigger_list_create(session_name
,
1619 state
->session_triggers_ht
);
1621 /* Add all triggers applying to the session named 'session_name'. */
1622 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1626 if (!trigger_applies_to_session(trigger_ht_element
->trigger
,
1631 ret
= lttng_session_trigger_list_add(session_trigger_list
,
1632 trigger_ht_element
->trigger
);
1640 DBG("Found %i triggers that apply to newly created session",
1642 return session_trigger_list
;
1644 lttng_session_trigger_list_destroy(session_trigger_list
);
1649 struct session_info
*find_or_create_session_info(
1650 struct notification_thread_state
*state
,
1651 const char *name
, uid_t uid
, gid_t gid
)
1653 struct session_info
*session
= NULL
;
1654 struct cds_lfht_node
*node
;
1655 struct cds_lfht_iter iter
;
1656 struct lttng_session_trigger_list
*trigger_list
;
1659 cds_lfht_lookup(state
->sessions_ht
,
1660 hash_key_str(name
, lttng_ht_seed
),
1664 node
= cds_lfht_iter_get_node(&iter
);
1666 DBG("Found session info of session \"%s\" (uid = %i, gid = %i)",
1668 session
= caa_container_of(node
, struct session_info
,
1670 LTTNG_ASSERT(session
->uid
== uid
);
1671 LTTNG_ASSERT(session
->gid
== gid
);
1672 session_info_get(session
);
1676 trigger_list
= lttng_session_trigger_list_build(state
, name
);
1677 if (!trigger_list
) {
1681 session
= session_info_create(name
, uid
, gid
, trigger_list
,
1682 state
->sessions_ht
);
1684 ERR("Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
1686 lttng_session_trigger_list_destroy(trigger_list
);
1689 trigger_list
= NULL
;
1691 cds_lfht_add(state
->sessions_ht
, hash_key_str(name
, lttng_ht_seed
),
1692 &session
->sessions_ht_node
);
1698 session_info_put(session
);
1703 int handle_notification_thread_command_add_channel(
1704 struct notification_thread_state
*state
,
1705 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1706 const char *channel_name
, enum lttng_domain_type channel_domain
,
1707 uint64_t channel_key_int
, uint64_t channel_capacity
,
1708 enum lttng_error_code
*cmd_result
)
1710 struct cds_list_head trigger_list
;
1711 struct channel_info
*new_channel_info
= NULL
;
1712 struct channel_key channel_key
= {
1713 .key
= channel_key_int
,
1714 .domain
= channel_domain
,
1716 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
1717 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1718 int trigger_count
= 0;
1719 struct cds_lfht_iter iter
;
1720 struct session_info
*session_info
= NULL
;
1722 DBG("Adding channel %s from session %s, channel key = %" PRIu64
" in %s domain",
1723 channel_name
, session_name
, channel_key_int
,
1724 lttng_domain_type_str(channel_domain
));
1726 CDS_INIT_LIST_HEAD(&trigger_list
);
1728 session_info
= find_or_create_session_info(state
, session_name
,
1729 session_uid
, session_gid
);
1730 if (!session_info
) {
1731 /* Allocation error or an internal error occurred. */
1735 new_channel_info
= channel_info_create(channel_name
, &channel_key
,
1736 channel_capacity
, session_info
);
1737 if (!new_channel_info
) {
1742 /* Build a list of all triggers applying to the new channel. */
1743 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1745 struct lttng_trigger_list_element
*new_element
;
1747 if (!trigger_applies_to_channel(trigger_ht_element
->trigger
,
1748 new_channel_info
)) {
1752 new_element
= (lttng_trigger_list_element
*) zmalloc(sizeof(*new_element
));
1757 CDS_INIT_LIST_HEAD(&new_element
->node
);
1758 new_element
->trigger
= trigger_ht_element
->trigger
;
1759 cds_list_add(&new_element
->node
, &trigger_list
);
1764 DBG("Found %i triggers that apply to newly added channel",
1766 channel_trigger_list
= (lttng_channel_trigger_list
*) zmalloc(sizeof(*channel_trigger_list
));
1767 if (!channel_trigger_list
) {
1770 channel_trigger_list
->channel_key
= new_channel_info
->key
;
1771 CDS_INIT_LIST_HEAD(&channel_trigger_list
->list
);
1772 cds_lfht_node_init(&channel_trigger_list
->channel_triggers_ht_node
);
1773 cds_list_splice(&trigger_list
, &channel_trigger_list
->list
);
1776 /* Add channel to the channel_ht which owns the channel_infos. */
1777 cds_lfht_add(state
->channels_ht
,
1778 hash_channel_key(&new_channel_info
->key
),
1779 &new_channel_info
->channels_ht_node
);
1781 * Add the list of triggers associated with this channel to the
1782 * channel_triggers_ht.
1784 cds_lfht_add(state
->channel_triggers_ht
,
1785 hash_channel_key(&new_channel_info
->key
),
1786 &channel_trigger_list
->channel_triggers_ht_node
);
1788 session_info_put(session_info
);
1789 *cmd_result
= LTTNG_OK
;
1792 channel_info_destroy(new_channel_info
);
1793 session_info_put(session_info
);
1798 void free_channel_trigger_list_rcu(struct rcu_head
*node
)
1800 free(caa_container_of(node
, struct lttng_channel_trigger_list
,
1805 void free_channel_state_sample_rcu(struct rcu_head
*node
)
1807 free(caa_container_of(node
, struct channel_state_sample
,
1812 int handle_notification_thread_command_remove_channel(
1813 struct notification_thread_state
*state
,
1814 uint64_t channel_key
, enum lttng_domain_type domain
,
1815 enum lttng_error_code
*cmd_result
)
1817 struct cds_lfht_node
*node
;
1818 struct cds_lfht_iter iter
;
1819 struct lttng_channel_trigger_list
*trigger_list
;
1820 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1821 struct channel_key key
= { .key
= channel_key
, .domain
= domain
};
1822 struct channel_info
*channel_info
;
1824 DBG("Removing channel key = %" PRIu64
" in %s domain",
1825 channel_key
, lttng_domain_type_str(domain
));
1829 cds_lfht_lookup(state
->channel_triggers_ht
,
1830 hash_channel_key(&key
),
1831 match_channel_trigger_list
,
1834 node
= cds_lfht_iter_get_node(&iter
);
1836 * There is a severe internal error if we are being asked to remove a
1837 * channel that doesn't exist.
1840 ERR("Channel being removed is unknown to the notification thread");
1844 /* Free the list of triggers associated with this channel. */
1845 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
1846 channel_triggers_ht_node
);
1847 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1848 &trigger_list
->list
, node
) {
1849 cds_list_del(&trigger_list_element
->node
);
1850 free(trigger_list_element
);
1852 cds_lfht_del(state
->channel_triggers_ht
, node
);
1853 call_rcu(&trigger_list
->rcu_node
, free_channel_trigger_list_rcu
);
1855 /* Free sampled channel state. */
1856 cds_lfht_lookup(state
->channel_state_ht
,
1857 hash_channel_key(&key
),
1858 match_channel_state_sample
,
1861 node
= cds_lfht_iter_get_node(&iter
);
1863 * This is expected to be NULL if the channel is destroyed before we
1864 * received a sample.
1867 struct channel_state_sample
*sample
= caa_container_of(node
,
1868 struct channel_state_sample
,
1869 channel_state_ht_node
);
1871 cds_lfht_del(state
->channel_state_ht
, node
);
1872 call_rcu(&sample
->rcu_node
, free_channel_state_sample_rcu
);
1875 /* Remove the channel from the channels_ht and free it. */
1876 cds_lfht_lookup(state
->channels_ht
,
1877 hash_channel_key(&key
),
1881 node
= cds_lfht_iter_get_node(&iter
);
1883 channel_info
= caa_container_of(node
, struct channel_info
,
1885 cds_lfht_del(state
->channels_ht
, node
);
1886 channel_info_destroy(channel_info
);
1889 *cmd_result
= LTTNG_OK
;
1894 int handle_notification_thread_command_session_rotation(
1895 struct notification_thread_state
*state
,
1896 enum notification_thread_command_type cmd_type
,
1897 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1898 uint64_t trace_archive_chunk_id
,
1899 struct lttng_trace_archive_location
*location
,
1900 enum lttng_error_code
*_cmd_result
)
1903 enum lttng_error_code cmd_result
= LTTNG_OK
;
1904 struct lttng_session_trigger_list
*trigger_list
;
1905 struct lttng_trigger_list_element
*trigger_list_element
;
1906 struct session_info
*session_info
;
1907 const struct lttng_credentials session_creds
= {
1908 .uid
= LTTNG_OPTIONAL_INIT_VALUE(session_uid
),
1909 .gid
= LTTNG_OPTIONAL_INIT_VALUE(session_gid
),
1914 session_info
= find_or_create_session_info(state
, session_name
,
1915 session_uid
, session_gid
);
1916 if (!session_info
) {
1917 /* Allocation error or an internal error occurred. */
1919 cmd_result
= LTTNG_ERR_NOMEM
;
1923 session_info
->rotation
.ongoing
=
1924 cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
;
1925 session_info
->rotation
.id
= trace_archive_chunk_id
;
1926 trigger_list
= get_session_trigger_list(state
, session_name
);
1927 if (!trigger_list
) {
1928 DBG("No triggers applying to session \"%s\" found",
1933 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
1935 const struct lttng_condition
*condition
;
1936 struct lttng_trigger
*trigger
;
1937 struct notification_client_list
*client_list
;
1938 struct lttng_evaluation
*evaluation
= NULL
;
1939 enum lttng_condition_type condition_type
;
1940 enum action_executor_status executor_status
;
1942 trigger
= trigger_list_element
->trigger
;
1943 condition
= lttng_trigger_get_const_condition(trigger
);
1944 LTTNG_ASSERT(condition
);
1945 condition_type
= lttng_condition_get_type(condition
);
1947 if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
&&
1948 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1950 } else if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
&&
1951 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
) {
1955 client_list
= get_client_list_from_condition(state
, condition
);
1956 if (cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1957 evaluation
= lttng_evaluation_session_rotation_ongoing_create(
1958 trace_archive_chunk_id
);
1960 evaluation
= lttng_evaluation_session_rotation_completed_create(
1961 trace_archive_chunk_id
, location
);
1965 /* Internal error */
1967 cmd_result
= LTTNG_ERR_UNK
;
1972 * Ownership of `evaluation` transferred to the action executor
1973 * no matter the result.
1975 executor_status
= action_executor_enqueue_trigger(
1976 state
->executor
, trigger
, evaluation
,
1977 &session_creds
, client_list
);
1979 switch (executor_status
) {
1980 case ACTION_EXECUTOR_STATUS_OK
:
1982 case ACTION_EXECUTOR_STATUS_ERROR
:
1983 case ACTION_EXECUTOR_STATUS_INVALID
:
1985 * TODO Add trigger identification (name/id) when
1986 * it is added to the API.
1988 ERR("Fatal error occurred while enqueuing action associated with session rotation trigger");
1991 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
1993 * TODO Add trigger identification (name/id) when
1994 * it is added to the API.
1996 * Not a fatal error.
1998 WARN("No space left when enqueuing action associated with session rotation trigger");
2006 notification_client_list_put(client_list
);
2007 if (caa_unlikely(ret
)) {
2012 session_info_put(session_info
);
2013 *_cmd_result
= cmd_result
;
2019 int handle_notification_thread_command_add_tracer_event_source(
2020 struct notification_thread_state
*state
,
2021 int tracer_event_source_fd
,
2022 enum lttng_domain_type domain_type
,
2023 enum lttng_error_code
*_cmd_result
)
2026 enum lttng_error_code cmd_result
= LTTNG_OK
;
2027 struct notification_event_tracer_event_source_element
*element
= NULL
;
2029 element
= (notification_event_tracer_event_source_element
*) zmalloc(sizeof(*element
));
2031 cmd_result
= LTTNG_ERR_NOMEM
;
2036 element
->fd
= tracer_event_source_fd
;
2037 element
->domain
= domain_type
;
2039 cds_list_add(&element
->node
, &state
->tracer_event_sources_list
);
2041 DBG3("Adding tracer event source fd to poll set: tracer_event_source_fd = %d, domain = '%s'",
2042 tracer_event_source_fd
,
2043 lttng_domain_type_str(domain_type
));
2045 /* Adding the read side pipe to the event poll. */
2046 ret
= lttng_poll_add(&state
->events
, tracer_event_source_fd
, LPOLLIN
| LPOLLERR
);
2048 ERR("Failed to add tracer event source to poll set: tracer_event_source_fd = %d, domain = '%s'",
2049 tracer_event_source_fd
,
2050 lttng_domain_type_str(element
->domain
));
2051 cds_list_del(&element
->node
);
2056 element
->is_fd_in_poll_set
= true;
2059 *_cmd_result
= cmd_result
;
2064 int drain_event_notifier_notification_pipe(
2065 struct notification_thread_state
*state
,
2066 int pipe
, enum lttng_domain_type domain
)
2068 struct lttng_poll_event events
= {0};
2071 ret
= lttng_poll_create(&events
, 1, LTTNG_CLOEXEC
);
2073 ERR("Error creating lttng_poll_event");
2077 ret
= lttng_poll_add(&events
, pipe
, LPOLLIN
);
2079 ERR("Error adding fd event notifier notification pipe to lttng_poll_event: fd = %d",
2086 * Continue to consume notifications as long as there are new
2087 * ones coming in. The tracer has been asked to stop producing
2090 * LPOLLIN is explicitly checked since LPOLLHUP is implicitly
2091 * monitored (on Linux, at least) and will be returned when
2092 * the pipe is closed but empty.
2094 ret
= lttng_poll_wait_interruptible(&events
, 0);
2095 if (ret
== 0 || (LTTNG_POLL_GETEV(&events
, 0) & LPOLLIN
) == 0) {
2096 /* No more notification to be read on this pipe. */
2099 } else if (ret
< 0) {
2100 PERROR("Failed on lttng_poll_wait_interruptible() call");
2105 ret
= handle_one_event_notifier_notification(state
, pipe
, domain
);
2107 ERR("Error consuming an event notifier notification from pipe: fd = %d",
2112 lttng_poll_clean(&events
);
2117 struct notification_event_tracer_event_source_element
*
2118 find_tracer_event_source_element(struct notification_thread_state
*state
,
2119 int tracer_event_source_fd
)
2121 struct notification_event_tracer_event_source_element
*source_element
;
2123 cds_list_for_each_entry(source_element
,
2124 &state
->tracer_event_sources_list
, node
) {
2125 if (source_element
->fd
== tracer_event_source_fd
) {
2130 source_element
= NULL
;
2132 return source_element
;
2136 int remove_tracer_event_source_from_pollset(
2137 struct notification_thread_state
*state
,
2138 struct notification_event_tracer_event_source_element
*source_element
)
2142 LTTNG_ASSERT(source_element
->is_fd_in_poll_set
);
2144 DBG3("Removing tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2146 lttng_domain_type_str(source_element
->domain
));
2148 /* Removing the fd from the event poll set. */
2149 ret
= lttng_poll_del(&state
->events
, source_element
->fd
);
2151 ERR("Failed to remove tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2153 lttng_domain_type_str(source_element
->domain
));
2158 source_element
->is_fd_in_poll_set
= false;
2161 * Force the notification thread to restart the poll() loop to ensure
2162 * that any events from the removed fd are removed.
2164 state
->restart_poll
= true;
2166 ret
= drain_event_notifier_notification_pipe(state
, source_element
->fd
,
2167 source_element
->domain
);
2169 ERR("Error draining event notifier notification: tracer_event_source_fd = %d, domain = %s",
2171 lttng_domain_type_str(source_element
->domain
));
2180 int handle_notification_thread_tracer_event_source_died(
2181 struct notification_thread_state
*state
,
2182 int tracer_event_source_fd
)
2185 struct notification_event_tracer_event_source_element
*source_element
;
2187 source_element
= find_tracer_event_source_element(state
,
2188 tracer_event_source_fd
);
2190 LTTNG_ASSERT(source_element
);
2192 ret
= remove_tracer_event_source_from_pollset(state
, source_element
);
2194 ERR("Failed to remove dead tracer event source from poll set");
2201 int handle_notification_thread_command_remove_tracer_event_source(
2202 struct notification_thread_state
*state
,
2203 int tracer_event_source_fd
,
2204 enum lttng_error_code
*_cmd_result
)
2207 enum lttng_error_code cmd_result
= LTTNG_OK
;
2208 struct notification_event_tracer_event_source_element
*source_element
= NULL
;
2210 source_element
= find_tracer_event_source_element(state
,
2211 tracer_event_source_fd
);
2213 LTTNG_ASSERT(source_element
);
2215 /* Remove the tracer source from the list. */
2216 cds_list_del(&source_element
->node
);
2218 if (!source_element
->is_fd_in_poll_set
) {
2219 /* Skip the poll set removal. */
2223 ret
= remove_tracer_event_source_from_pollset(state
, source_element
);
2225 ERR("Failed to remove tracer event source from poll set");
2226 cmd_result
= LTTNG_ERR_FATAL
;
2230 free(source_element
);
2231 *_cmd_result
= cmd_result
;
2235 static int handle_notification_thread_command_list_triggers(
2236 struct notification_thread_handle
*handle
,
2237 struct notification_thread_state
*state
,
2239 struct lttng_triggers
**triggers
,
2240 enum lttng_error_code
*_cmd_result
)
2243 enum lttng_error_code cmd_result
= LTTNG_OK
;
2244 struct cds_lfht_iter iter
;
2245 struct lttng_trigger_ht_element
*trigger_ht_element
;
2246 struct lttng_triggers
*local_triggers
= NULL
;
2247 const struct lttng_credentials
*creds
;
2251 local_triggers
= lttng_triggers_create();
2252 if (!local_triggers
) {
2253 /* Not a fatal error. */
2254 cmd_result
= LTTNG_ERR_NOMEM
;
2258 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
,
2259 trigger_ht_element
, node
) {
2261 * Only return the triggers to which the client has access.
2262 * The root user has visibility over all triggers.
2264 creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
2265 if (client_uid
!= lttng_credentials_get_uid(creds
) && client_uid
!= 0) {
2269 ret
= lttng_triggers_add(local_triggers
,
2270 trigger_ht_element
->trigger
);
2272 /* Not a fatal error. */
2274 cmd_result
= LTTNG_ERR_NOMEM
;
2279 /* Transferring ownership to the caller. */
2280 *triggers
= local_triggers
;
2281 local_triggers
= NULL
;
2285 lttng_triggers_destroy(local_triggers
);
2286 *_cmd_result
= cmd_result
;
2290 static inline void get_trigger_info_for_log(const struct lttng_trigger
*trigger
,
2291 const char **trigger_name
,
2292 uid_t
*trigger_owner_uid
)
2294 enum lttng_trigger_status trigger_status
;
2296 trigger_status
= lttng_trigger_get_name(trigger
, trigger_name
);
2297 switch (trigger_status
) {
2298 case LTTNG_TRIGGER_STATUS_OK
:
2300 case LTTNG_TRIGGER_STATUS_UNSET
:
2301 *trigger_name
= "(anonymous)";
2307 trigger_status
= lttng_trigger_get_owner_uid(trigger
,
2309 LTTNG_ASSERT(trigger_status
== LTTNG_TRIGGER_STATUS_OK
);
2312 static int handle_notification_thread_command_get_trigger(
2313 struct notification_thread_state
*state
,
2314 const struct lttng_trigger
*trigger
,
2315 struct lttng_trigger
**registered_trigger
,
2316 enum lttng_error_code
*_cmd_result
)
2319 struct cds_lfht_iter iter
;
2320 struct lttng_trigger_ht_element
*trigger_ht_element
;
2321 enum lttng_error_code cmd_result
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
2322 const char *trigger_name
;
2323 uid_t trigger_owner_uid
;
2327 cds_lfht_for_each_entry(
2328 state
->triggers_ht
, &iter
, trigger_ht_element
, node
) {
2329 if (lttng_trigger_is_equal(
2330 trigger
, trigger_ht_element
->trigger
)) {
2331 /* Take one reference on the return trigger. */
2332 *registered_trigger
= trigger_ht_element
->trigger
;
2333 lttng_trigger_get(*registered_trigger
);
2335 cmd_result
= LTTNG_OK
;
2340 /* Not a fatal error if the trigger is not found. */
2341 get_trigger_info_for_log(trigger
, &trigger_name
, &trigger_owner_uid
);
2342 DBG("Failed to retrieve registered version of trigger: trigger name = '%s', trigger owner uid = %d",
2343 trigger_name
, (int) trigger_owner_uid
);
2349 *_cmd_result
= cmd_result
;
2354 bool condition_is_supported(struct lttng_condition
*condition
)
2358 switch (lttng_condition_get_type(condition
)) {
2359 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
2360 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
2363 enum lttng_domain_type domain
;
2365 ret
= lttng_condition_buffer_usage_get_domain_type(condition
,
2367 LTTNG_ASSERT(ret
== 0);
2369 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2370 is_supported
= true;
2375 * Older kernel tracers don't expose the API to monitor their
2376 * buffers. Therefore, we reject triggers that require that
2377 * mechanism to be available to be evaluated.
2379 * Assume unsupported on error.
2381 is_supported
= kernel_supports_ring_buffer_snapshot_sample_positions() == 1;
2384 case LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES
:
2386 const struct lttng_event_rule
*event_rule
;
2387 enum lttng_domain_type domain
;
2388 const enum lttng_condition_status status
=
2389 lttng_condition_event_rule_matches_get_rule(
2390 condition
, &event_rule
);
2392 LTTNG_ASSERT(status
== LTTNG_CONDITION_STATUS_OK
);
2394 domain
= lttng_event_rule_get_domain_type(event_rule
);
2395 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2396 is_supported
= true;
2401 * Older kernel tracers can't emit notification. Therefore, we
2402 * reject triggers that require that mechanism to be available
2405 * Assume unsupported on error.
2407 is_supported
= kernel_supports_event_notifiers() == 1;
2411 is_supported
= true;
2414 return is_supported
;
2417 /* Must be called with RCU read lock held. */
2419 int bind_trigger_to_matching_session(struct lttng_trigger
*trigger
,
2420 struct notification_thread_state
*state
)
2423 const struct lttng_condition
*condition
;
2424 const char *session_name
;
2425 struct lttng_session_trigger_list
*trigger_list
;
2427 ASSERT_RCU_READ_LOCKED();
2429 condition
= lttng_trigger_get_const_condition(trigger
);
2430 switch (lttng_condition_get_type(condition
)) {
2431 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
2432 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
2434 enum lttng_condition_status status
;
2436 status
= lttng_condition_session_rotation_get_session_name(
2437 condition
, &session_name
);
2438 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
2439 ERR("Failed to bind trigger to session: unable to get 'session_rotation' condition's session name");
2450 trigger_list
= get_session_trigger_list(state
, session_name
);
2451 if (!trigger_list
) {
2452 DBG("Unable to bind trigger applying to session \"%s\" as it is not yet known to the notification system",
2458 DBG("Newly registered trigger bound to session \"%s\"",
2460 ret
= lttng_session_trigger_list_add(trigger_list
, trigger
);
2465 /* Must be called with RCU read lock held. */
2467 int bind_trigger_to_matching_channels(struct lttng_trigger
*trigger
,
2468 struct notification_thread_state
*state
)
2471 struct cds_lfht_node
*node
;
2472 struct cds_lfht_iter iter
;
2473 struct channel_info
*channel
;
2475 ASSERT_RCU_READ_LOCKED();
2477 cds_lfht_for_each_entry(state
->channels_ht
, &iter
, channel
,
2479 struct lttng_trigger_list_element
*trigger_list_element
;
2480 struct lttng_channel_trigger_list
*trigger_list
;
2481 struct cds_lfht_iter lookup_iter
;
2483 if (!trigger_applies_to_channel(trigger
, channel
)) {
2487 cds_lfht_lookup(state
->channel_triggers_ht
,
2488 hash_channel_key(&channel
->key
),
2489 match_channel_trigger_list
,
2492 node
= cds_lfht_iter_get_node(&lookup_iter
);
2494 trigger_list
= caa_container_of(node
,
2495 struct lttng_channel_trigger_list
,
2496 channel_triggers_ht_node
);
2498 trigger_list_element
= (lttng_trigger_list_element
*) zmalloc(sizeof(*trigger_list_element
));
2499 if (!trigger_list_element
) {
2503 CDS_INIT_LIST_HEAD(&trigger_list_element
->node
);
2504 trigger_list_element
->trigger
= trigger
;
2505 cds_list_add(&trigger_list_element
->node
, &trigger_list
->list
);
2506 DBG("Newly registered trigger bound to channel \"%s\"",
2514 bool is_trigger_action_notify(const struct lttng_trigger
*trigger
)
2516 bool is_notify
= false;
2517 unsigned int i
, count
;
2518 enum lttng_action_status action_status
;
2519 const struct lttng_action
*action
=
2520 lttng_trigger_get_const_action(trigger
);
2521 enum lttng_action_type action_type
;
2523 LTTNG_ASSERT(action
);
2524 action_type
= lttng_action_get_type(action
);
2525 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2528 } else if (action_type
!= LTTNG_ACTION_TYPE_LIST
) {
2532 action_status
= lttng_action_list_get_count(action
, &count
);
2533 LTTNG_ASSERT(action_status
== LTTNG_ACTION_STATUS_OK
);
2535 for (i
= 0; i
< count
; i
++) {
2536 const struct lttng_action
*inner_action
=
2537 lttng_action_list_get_at_index(
2540 action_type
= lttng_action_get_type(inner_action
);
2541 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2551 static bool trigger_name_taken(struct notification_thread_state
*state
,
2552 const struct lttng_trigger
*trigger
)
2554 struct cds_lfht_iter iter
;
2557 * No duplicata is allowed in the triggers_by_name_uid_ht.
2558 * The match is done against the trigger name and uid.
2560 cds_lfht_lookup(state
->triggers_by_name_uid_ht
,
2561 hash_trigger_by_name_uid(trigger
),
2562 match_trigger_by_name_uid
,
2565 return !!cds_lfht_iter_get_node(&iter
);
2569 enum lttng_error_code
generate_trigger_name(
2570 struct notification_thread_state
*state
,
2571 struct lttng_trigger
*trigger
, const char **name
)
2573 enum lttng_error_code ret_code
= LTTNG_OK
;
2575 enum lttng_trigger_status status
;
2578 const int ret
= lttng_trigger_generate_name(trigger
,
2579 state
->trigger_id
.name_offset
++);
2581 /* The only reason this can fail right now. */
2582 ret_code
= LTTNG_ERR_NOMEM
;
2586 status
= lttng_trigger_get_name(trigger
, name
);
2587 LTTNG_ASSERT(status
== LTTNG_TRIGGER_STATUS_OK
);
2589 taken
= trigger_name_taken(state
, trigger
);
2590 } while (taken
|| state
->trigger_id
.name_offset
== UINT64_MAX
);
2596 void notif_thread_state_remove_trigger_ht_elem(
2597 struct notification_thread_state
*state
,
2598 struct lttng_trigger_ht_element
*trigger_ht_element
)
2600 LTTNG_ASSERT(state
);
2601 LTTNG_ASSERT(trigger_ht_element
);
2603 cds_lfht_del(state
->triggers_ht
, &trigger_ht_element
->node
);
2604 cds_lfht_del(state
->triggers_by_name_uid_ht
, &trigger_ht_element
->node_by_name_uid
);
2608 enum lttng_error_code
setup_tracer_notifier(
2609 struct notification_thread_state
*state
,
2610 struct lttng_trigger
*trigger
)
2612 enum lttng_error_code ret
;
2613 enum event_notifier_error_accounting_status error_accounting_status
;
2614 struct cds_lfht_node
*node
;
2615 uint64_t error_counter_index
= 0;
2616 struct lttng_condition
*condition
= lttng_trigger_get_condition(trigger
);
2617 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
= NULL
;
2619 trigger_tokens_ht_element
= (notification_trigger_tokens_ht_element
*) zmalloc(sizeof(*trigger_tokens_ht_element
));
2620 if (!trigger_tokens_ht_element
) {
2621 ret
= LTTNG_ERR_NOMEM
;
2625 /* Add trigger token to the trigger_tokens_ht. */
2626 cds_lfht_node_init(&trigger_tokens_ht_element
->node
);
2627 trigger_tokens_ht_element
->token
= LTTNG_OPTIONAL_GET(trigger
->tracer_token
);
2628 trigger_tokens_ht_element
->trigger
= trigger
;
2630 node
= cds_lfht_add_unique(state
->trigger_tokens_ht
,
2631 hash_key_u64(&trigger_tokens_ht_element
->token
, lttng_ht_seed
),
2632 match_trigger_token
,
2633 &trigger_tokens_ht_element
->token
,
2634 &trigger_tokens_ht_element
->node
);
2635 if (node
!= &trigger_tokens_ht_element
->node
) {
2636 ret
= LTTNG_ERR_TRIGGER_EXISTS
;
2637 goto error_free_ht_element
;
2640 error_accounting_status
= event_notifier_error_accounting_register_event_notifier(
2641 trigger
, &error_counter_index
);
2642 if (error_accounting_status
!= EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK
) {
2643 if (error_accounting_status
== EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_NO_INDEX_AVAILABLE
) {
2644 DBG("Trigger list error accounting counter full.");
2645 ret
= LTTNG_ERR_EVENT_NOTIFIER_ERROR_ACCOUNTING_FULL
;
2647 ERR("Error registering trigger for error accounting");
2648 ret
= LTTNG_ERR_EVENT_NOTIFIER_REGISTRATION
;
2651 goto error_remove_ht_element
;
2654 lttng_condition_event_rule_matches_set_error_counter_index(
2655 condition
, error_counter_index
);
2660 error_remove_ht_element
:
2661 cds_lfht_del(state
->trigger_tokens_ht
, &trigger_tokens_ht_element
->node
);
2662 error_free_ht_element
:
2663 free(trigger_tokens_ht_element
);
2669 * FIXME A client's credentials are not checked when registering a trigger.
2671 * The effects of this are benign since:
2672 * - The client will succeed in registering the trigger, as it is valid,
2673 * - The trigger will, internally, be bound to the channel/session,
2674 * - The notifications will not be sent since the client's credentials
2675 * are checked against the channel at that moment.
2677 * If this function returns a non-zero value, it means something is
2678 * fundamentally broken and the whole subsystem/thread will be torn down.
2680 * If a non-fatal error occurs, just set the cmd_result to the appropriate
2684 int handle_notification_thread_command_register_trigger(
2685 struct notification_thread_state
*state
,
2686 struct lttng_trigger
*trigger
,
2687 bool is_trigger_anonymous
,
2688 enum lttng_error_code
*cmd_result
)
2691 struct lttng_condition
*condition
;
2692 struct notification_client_list
*client_list
= NULL
;
2693 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2694 struct cds_lfht_node
*node
;
2695 const char* trigger_name
;
2696 bool free_trigger
= true;
2697 struct lttng_evaluation
*evaluation
= NULL
;
2698 struct lttng_credentials object_creds
;
2701 enum action_executor_status executor_status
;
2702 const uint64_t trigger_tracer_token
=
2703 state
->trigger_id
.next_tracer_token
++;
2707 /* Set the trigger's tracer token. */
2708 lttng_trigger_set_tracer_token(trigger
, trigger_tracer_token
);
2710 if (!is_trigger_anonymous
) {
2711 if (lttng_trigger_get_name(trigger
, &trigger_name
) ==
2712 LTTNG_TRIGGER_STATUS_UNSET
) {
2713 const enum lttng_error_code ret_code
=
2714 generate_trigger_name(state
, trigger
,
2717 if (ret_code
!= LTTNG_OK
) {
2720 *cmd_result
= ret_code
;
2723 } else if (trigger_name_taken(state
, trigger
)) {
2724 /* Not a fatal error. */
2725 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2730 trigger_name
= "(anonymous)";
2733 condition
= lttng_trigger_get_condition(trigger
);
2734 LTTNG_ASSERT(condition
);
2736 /* Some conditions require tracers to implement a minimal ABI version. */
2737 if (!condition_is_supported(condition
)) {
2738 *cmd_result
= LTTNG_ERR_NOT_SUPPORTED
;
2742 trigger_ht_element
= (lttng_trigger_ht_element
*) zmalloc(sizeof(*trigger_ht_element
));
2743 if (!trigger_ht_element
) {
2748 /* Add trigger to the trigger_ht. */
2749 cds_lfht_node_init(&trigger_ht_element
->node
);
2750 cds_lfht_node_init(&trigger_ht_element
->node_by_name_uid
);
2751 trigger_ht_element
->trigger
= trigger
;
2753 node
= cds_lfht_add_unique(state
->triggers_ht
,
2754 lttng_condition_hash(condition
),
2757 &trigger_ht_element
->node
);
2758 if (node
!= &trigger_ht_element
->node
) {
2759 /* Not a fatal error, simply report it to the client. */
2760 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2761 goto error_free_ht_element
;
2764 node
= cds_lfht_add_unique(state
->triggers_by_name_uid_ht
,
2765 hash_trigger_by_name_uid(trigger
),
2766 match_trigger_by_name_uid
,
2768 &trigger_ht_element
->node_by_name_uid
);
2769 if (node
!= &trigger_ht_element
->node_by_name_uid
) {
2770 /* Internal error: add to triggers_ht should have failed. */
2772 goto error_free_ht_element
;
2775 /* From this point consider the trigger registered. */
2776 lttng_trigger_set_as_registered(trigger
);
2779 * Some triggers might need a tracer notifier depending on its
2780 * condition and actions.
2782 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
2783 enum lttng_error_code error_code
;
2785 error_code
= setup_tracer_notifier(state
, trigger
);
2786 if (error_code
!= LTTNG_OK
) {
2787 notif_thread_state_remove_trigger_ht_elem(state
,
2788 trigger_ht_element
);
2789 if (error_code
== LTTNG_ERR_NOMEM
) {
2792 *cmd_result
= error_code
;
2796 goto error_free_ht_element
;
2801 * The rest only applies to triggers that have a "notify" action.
2802 * It is not skipped as this is the only action type currently
2805 if (is_trigger_action_notify(trigger
)) {
2807 * Find or create the client list of this condition. It may
2808 * already be present if another trigger is already registered
2809 * with the same condition.
2811 client_list
= get_client_list_from_condition(state
, condition
);
2814 * No client list for this condition yet. We create new
2815 * one and build it up.
2817 client_list
= notification_client_list_create(state
, condition
);
2819 ERR("Error creating notification client list for trigger %s", trigger
->name
);
2820 goto error_free_ht_element
;
2824 CDS_INIT_LIST_HEAD(&trigger_ht_element
->client_list_trigger_node
);
2826 pthread_mutex_lock(&client_list
->lock
);
2827 cds_list_add(&trigger_ht_element
->client_list_trigger_node
, &client_list
->triggers_list
);
2828 pthread_mutex_unlock(&client_list
->lock
);
2832 * Ownership of the trigger and of its wrapper was transfered to
2833 * the triggers_ht. Same for token ht element if necessary.
2835 trigger_ht_element
= NULL
;
2836 free_trigger
= false;
2838 switch (get_condition_binding_object(condition
)) {
2839 case LTTNG_OBJECT_TYPE_SESSION
:
2840 /* Add the trigger to the list if it matches a known session. */
2841 ret
= bind_trigger_to_matching_session(trigger
, state
);
2843 goto error_free_ht_element
;
2846 case LTTNG_OBJECT_TYPE_CHANNEL
:
2848 * Add the trigger to list of triggers bound to the channels
2851 ret
= bind_trigger_to_matching_channels(trigger
, state
);
2853 goto error_free_ht_element
;
2856 case LTTNG_OBJECT_TYPE_NONE
:
2859 ERR("Unknown object type on which to bind a newly registered trigger was encountered");
2861 goto error_free_ht_element
;
2865 * The new trigger's condition must be evaluated against the current
2868 * In the case of `notify` action, nothing preventing clients from
2869 * subscribing to a condition before the corresponding trigger is
2870 * registered, we have to evaluate this new condition right away.
2872 * At some point, we were waiting for the next "evaluation" (e.g. on
2873 * reception of a channel sample) to evaluate this new condition, but
2876 * The reason it was broken is that waiting for the next sample
2877 * does not allow us to properly handle transitions for edge-triggered
2880 * Consider this example: when we handle a new channel sample, we
2881 * evaluate each conditions twice: once with the previous state, and
2882 * again with the newest state. We then use those two results to
2883 * determine whether a state change happened: a condition was false and
2884 * became true. If a state change happened, we have to notify clients.
2886 * Now, if a client subscribes to a given notification and registers
2887 * a trigger *after* that subscription, we have to make sure the
2888 * condition is evaluated at this point while considering only the
2889 * current state. Otherwise, the next evaluation cycle may only see
2890 * that the evaluations remain the same (true for samples n-1 and n) and
2891 * the client will never know that the condition has been met.
2893 switch (get_condition_binding_object(condition
)) {
2894 case LTTNG_OBJECT_TYPE_SESSION
:
2895 ret
= evaluate_session_condition_for_client(condition
, state
,
2896 &evaluation
, &object_uid
,
2898 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2899 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2901 case LTTNG_OBJECT_TYPE_CHANNEL
:
2902 ret
= evaluate_channel_condition_for_client(condition
, state
,
2903 &evaluation
, &object_uid
,
2905 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2906 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2908 case LTTNG_OBJECT_TYPE_NONE
:
2911 case LTTNG_OBJECT_TYPE_UNKNOWN
:
2919 goto error_free_ht_element
;
2922 DBG("Newly registered trigger's condition evaluated to %s",
2923 evaluation
? "true" : "false");
2925 /* Evaluation yielded nothing. Normal exit. */
2931 * Ownership of `evaluation` transferred to the action executor
2932 * no matter the result.
2934 executor_status
= action_executor_enqueue_trigger(state
->executor
,
2935 trigger
, evaluation
, &object_creds
, client_list
);
2937 switch (executor_status
) {
2938 case ACTION_EXECUTOR_STATUS_OK
:
2940 case ACTION_EXECUTOR_STATUS_ERROR
:
2941 case ACTION_EXECUTOR_STATUS_INVALID
:
2943 * TODO Add trigger identification (name/id) when
2944 * it is added to the API.
2946 ERR("Fatal error occurred while enqueuing action associated to newly registered trigger");
2948 goto error_free_ht_element
;
2949 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
2951 * TODO Add trigger identification (name/id) when
2952 * it is added to the API.
2954 * Not a fatal error.
2956 WARN("No space left when enqueuing action associated to newly registered trigger");
2964 *cmd_result
= LTTNG_OK
;
2965 DBG("Registered trigger: name = `%s`, tracer token = %" PRIu64
,
2966 trigger_name
, trigger_tracer_token
);
2969 error_free_ht_element
:
2970 if (trigger_ht_element
) {
2971 /* Delayed removal due to RCU constraint on delete. */
2972 call_rcu(&trigger_ht_element
->rcu_node
,
2973 free_lttng_trigger_ht_element_rcu
);
2978 * Other objects might have a reference to the trigger, mark it
2981 lttng_trigger_set_as_unregistered(trigger
);
2982 lttng_trigger_destroy(trigger
);
2990 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
)
2992 free(caa_container_of(node
, struct lttng_trigger_ht_element
,
2997 void free_notification_trigger_tokens_ht_element_rcu(struct rcu_head
*node
)
2999 free(caa_container_of(node
, struct notification_trigger_tokens_ht_element
,
3004 void teardown_tracer_notifier(struct notification_thread_state
*state
,
3005 const struct lttng_trigger
*trigger
)
3007 struct cds_lfht_iter iter
;
3008 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
;
3010 cds_lfht_for_each_entry(state
->trigger_tokens_ht
, &iter
,
3011 trigger_tokens_ht_element
, node
) {
3013 if (!lttng_trigger_is_equal(trigger
,
3014 trigger_tokens_ht_element
->trigger
)) {
3018 event_notifier_error_accounting_unregister_event_notifier(
3019 trigger_tokens_ht_element
->trigger
);
3021 /* TODO talk to all app and remove it */
3022 DBG("Removed trigger from tokens_ht");
3023 cds_lfht_del(state
->trigger_tokens_ht
,
3024 &trigger_tokens_ht_element
->node
);
3026 call_rcu(&trigger_tokens_ht_element
->rcu_node
,
3027 free_notification_trigger_tokens_ht_element_rcu
);
3034 int handle_notification_thread_command_unregister_trigger(
3035 struct notification_thread_state
*state
,
3036 const struct lttng_trigger
*trigger
,
3037 enum lttng_error_code
*_cmd_reply
)
3039 struct cds_lfht_iter iter
;
3040 struct cds_lfht_node
*triggers_ht_node
;
3041 struct lttng_channel_trigger_list
*trigger_list
;
3042 struct notification_client_list
*client_list
;
3043 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
3044 const struct lttng_condition
*condition
= lttng_trigger_get_const_condition(
3046 enum lttng_error_code cmd_reply
;
3050 cds_lfht_lookup(state
->triggers_ht
,
3051 lttng_condition_hash(condition
),
3055 triggers_ht_node
= cds_lfht_iter_get_node(&iter
);
3056 if (!triggers_ht_node
) {
3057 cmd_reply
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
3060 cmd_reply
= LTTNG_OK
;
3063 trigger_ht_element
= caa_container_of(triggers_ht_node
,
3064 struct lttng_trigger_ht_element
, node
);
3066 /* Remove trigger from channel_triggers_ht. */
3067 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
, trigger_list
,
3068 channel_triggers_ht_node
) {
3069 struct lttng_trigger_list_element
*trigger_element
, *tmp
;
3071 cds_list_for_each_entry_safe(trigger_element
, tmp
,
3072 &trigger_list
->list
, node
) {
3073 if (!lttng_trigger_is_equal(trigger
, trigger_element
->trigger
)) {
3077 DBG("Removed trigger from channel_triggers_ht");
3078 cds_list_del(&trigger_element
->node
);
3079 /* A trigger can only appear once per channel */
3084 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
3085 teardown_tracer_notifier(state
, trigger
);
3088 if (is_trigger_action_notify(trigger
)) {
3090 * Remove and release the client list from
3091 * notification_trigger_clients_ht.
3093 client_list
= get_client_list_from_condition(state
, condition
);
3094 LTTNG_ASSERT(client_list
);
3096 pthread_mutex_lock(&client_list
->lock
);
3097 cds_list_del(&trigger_ht_element
->client_list_trigger_node
);
3098 pthread_mutex_unlock(&client_list
->lock
);
3100 /* Put new reference and the hashtable's reference. */
3101 notification_client_list_put(client_list
);
3102 notification_client_list_put(client_list
);
3106 /* Remove trigger from triggers_ht. */
3107 notif_thread_state_remove_trigger_ht_elem(state
, trigger_ht_element
);
3109 /* Release the ownership of the trigger. */
3110 lttng_trigger_destroy(trigger_ht_element
->trigger
);
3111 call_rcu(&trigger_ht_element
->rcu_node
, free_lttng_trigger_ht_element_rcu
);
3115 *_cmd_reply
= cmd_reply
;
3120 /* Returns 0 on success, 1 on exit requested, negative value on error. */
3121 int handle_notification_thread_command(
3122 struct notification_thread_handle
*handle
,
3123 struct notification_thread_state
*state
)
3127 struct notification_thread_command
*cmd
;
3129 /* Read the event pipe to put it back into a quiescent state. */
3130 ret
= lttng_read(lttng_pipe_get_readfd(handle
->cmd_queue
.event_pipe
), &counter
,
3132 if (ret
!= sizeof(counter
)) {
3136 pthread_mutex_lock(&handle
->cmd_queue
.lock
);
3137 cmd
= cds_list_first_entry(&handle
->cmd_queue
.list
,
3138 struct notification_thread_command
, cmd_list_node
);
3139 cds_list_del(&cmd
->cmd_list_node
);
3140 pthread_mutex_unlock(&handle
->cmd_queue
.lock
);
3142 DBG("Received `%s` command",
3143 notification_command_type_str(cmd
->type
));
3144 switch (cmd
->type
) {
3145 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
3146 ret
= handle_notification_thread_command_register_trigger(state
,
3147 cmd
->parameters
.register_trigger
.trigger
,
3148 cmd
->parameters
.register_trigger
.is_trigger_anonymous
,
3151 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
3152 ret
= handle_notification_thread_command_unregister_trigger(
3154 cmd
->parameters
.unregister_trigger
.trigger
,
3157 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
3158 ret
= handle_notification_thread_command_add_channel(
3160 cmd
->parameters
.add_channel
.session
.name
,
3161 cmd
->parameters
.add_channel
.session
.uid
,
3162 cmd
->parameters
.add_channel
.session
.gid
,
3163 cmd
->parameters
.add_channel
.channel
.name
,
3164 cmd
->parameters
.add_channel
.channel
.domain
,
3165 cmd
->parameters
.add_channel
.channel
.key
,
3166 cmd
->parameters
.add_channel
.channel
.capacity
,
3169 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
3170 ret
= handle_notification_thread_command_remove_channel(
3171 state
, cmd
->parameters
.remove_channel
.key
,
3172 cmd
->parameters
.remove_channel
.domain
,
3175 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
3176 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
3177 ret
= handle_notification_thread_command_session_rotation(
3180 cmd
->parameters
.session_rotation
.session_name
,
3181 cmd
->parameters
.session_rotation
.uid
,
3182 cmd
->parameters
.session_rotation
.gid
,
3183 cmd
->parameters
.session_rotation
.trace_archive_chunk_id
,
3184 cmd
->parameters
.session_rotation
.location
,
3187 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
3188 ret
= handle_notification_thread_command_add_tracer_event_source(
3190 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3191 cmd
->parameters
.tracer_event_source
.domain
,
3194 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
3195 ret
= handle_notification_thread_command_remove_tracer_event_source(
3197 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3200 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
3202 struct lttng_triggers
*triggers
= NULL
;
3204 ret
= handle_notification_thread_command_list_triggers(
3207 cmd
->parameters
.list_triggers
.uid
,
3210 cmd
->reply
.list_triggers
.triggers
= triggers
;
3214 case NOTIFICATION_COMMAND_TYPE_QUIT
:
3215 cmd
->reply_code
= LTTNG_OK
;
3218 case NOTIFICATION_COMMAND_TYPE_GET_TRIGGER
:
3220 struct lttng_trigger
*trigger
= NULL
;
3222 ret
= handle_notification_thread_command_get_trigger(state
,
3223 cmd
->parameters
.get_trigger
.trigger
, &trigger
,
3225 cmd
->reply
.get_trigger
.trigger
= trigger
;
3228 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
3230 const enum client_transmission_status client_status
=
3231 cmd
->parameters
.client_communication_update
3233 const notification_client_id client_id
=
3234 cmd
->parameters
.client_communication_update
.id
;
3235 struct notification_client
*client
;
3238 client
= get_client_from_id(client_id
, state
);
3242 * Client error was probably already picked-up by the
3243 * notification thread or it has disconnected
3244 * gracefully while this command was queued.
3246 DBG("Failed to find notification client to update communication status, client id = %" PRIu64
,
3250 ret
= client_handle_transmission_status(
3251 client
, client_status
, state
);
3257 ERR("Unknown internal command received");
3265 if (cmd
->is_async
) {
3269 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3273 /* Wake-up and return a fatal error to the calling thread. */
3274 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3275 cmd
->reply_code
= LTTNG_ERR_FATAL
;
3277 /* Indicate a fatal error to the caller. */
3282 int socket_set_non_blocking(int socket
)
3286 /* Set the pipe as non-blocking. */
3287 ret
= fcntl(socket
, F_GETFL
, 0);
3289 PERROR("fcntl get socket flags");
3294 ret
= fcntl(socket
, F_SETFL
, flags
| O_NONBLOCK
);
3296 PERROR("fcntl set O_NONBLOCK socket flag");
3299 DBG("Client socket (fd = %i) set as non-blocking", socket
);
3305 int client_reset_inbound_state(struct notification_client
*client
)
3310 lttng_payload_clear(&client
->communication
.inbound
.payload
);
3312 client
->communication
.inbound
.bytes_to_receive
=
3313 sizeof(struct lttng_notification_channel_message
);
3314 client
->communication
.inbound
.msg_type
=
3315 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
;
3316 LTTNG_SOCK_SET_UID_CRED(&client
->communication
.inbound
.creds
, -1);
3317 LTTNG_SOCK_SET_GID_CRED(&client
->communication
.inbound
.creds
, -1);
3318 ret
= lttng_dynamic_buffer_set_size(
3319 &client
->communication
.inbound
.payload
.buffer
,
3320 client
->communication
.inbound
.bytes_to_receive
);
3325 int handle_notification_thread_client_connect(
3326 struct notification_thread_state
*state
)
3329 struct notification_client
*client
;
3331 DBG("Handling new notification channel client connection");
3333 client
= (notification_client
*) zmalloc(sizeof(*client
));
3340 pthread_mutex_init(&client
->lock
, NULL
);
3341 client
->id
= state
->next_notification_client_id
++;
3342 CDS_INIT_LIST_HEAD(&client
->condition_list
);
3343 lttng_payload_init(&client
->communication
.inbound
.payload
);
3344 lttng_payload_init(&client
->communication
.outbound
.payload
);
3345 client
->communication
.inbound
.expect_creds
= true;
3347 ret
= client_reset_inbound_state(client
);
3349 ERR("Failed to reset client communication's inbound state");
3354 ret
= lttcomm_accept_unix_sock(state
->notification_channel_socket
);
3356 ERR("Failed to accept new notification channel client connection");
3361 client
->socket
= ret
;
3363 ret
= socket_set_non_blocking(client
->socket
);
3365 ERR("Failed to set new notification channel client connection socket as non-blocking");
3369 ret
= lttcomm_setsockopt_creds_unix_sock(client
->socket
);
3371 ERR("Failed to set socket options on new notification channel client socket");
3376 ret
= lttng_poll_add(&state
->events
, client
->socket
,
3377 LPOLLIN
| LPOLLERR
|
3378 LPOLLHUP
| LPOLLRDHUP
);
3380 ERR("Failed to add notification channel client socket to poll set");
3384 DBG("Added new notification channel client socket (%i) to poll set",
3388 cds_lfht_add(state
->client_socket_ht
,
3389 hash_client_socket(client
->socket
),
3390 &client
->client_socket_ht_node
);
3391 cds_lfht_add(state
->client_id_ht
,
3392 hash_client_id(client
->id
),
3393 &client
->client_id_ht_node
);
3399 notification_client_destroy(client
, state
);
3404 * RCU read-lock must be held by the caller.
3405 * Client lock must _not_ be held by the caller.
3408 int notification_thread_client_disconnect(
3409 struct notification_client
*client
,
3410 struct notification_thread_state
*state
)
3413 struct lttng_condition_list_element
*condition_list_element
, *tmp
;
3415 ASSERT_RCU_READ_LOCKED();
3417 /* Acquire the client lock to disable its communication atomically. */
3418 pthread_mutex_lock(&client
->lock
);
3419 client
->communication
.active
= false;
3420 cds_lfht_del(state
->client_socket_ht
, &client
->client_socket_ht_node
);
3421 cds_lfht_del(state
->client_id_ht
, &client
->client_id_ht_node
);
3422 pthread_mutex_unlock(&client
->lock
);
3424 ret
= lttng_poll_del(&state
->events
, client
->socket
);
3426 ERR("Failed to remove client socket %d from poll set",
3430 /* Release all conditions to which the client was subscribed. */
3431 cds_list_for_each_entry_safe(condition_list_element
, tmp
,
3432 &client
->condition_list
, node
) {
3433 (void) notification_thread_client_unsubscribe(client
,
3434 condition_list_element
->condition
, state
, NULL
);
3438 * Client no longer accessible to other threads (through the
3441 notification_client_destroy(client
, state
);
3445 int handle_notification_thread_client_disconnect(
3446 int client_socket
, struct notification_thread_state
*state
)
3449 struct notification_client
*client
;
3452 DBG("Closing client connection (socket fd = %i)",
3454 client
= get_client_from_socket(client_socket
, state
);
3456 /* Internal state corruption, fatal error. */
3457 ERR("Unable to find client (socket fd = %i)",
3463 ret
= notification_thread_client_disconnect(client
, state
);
3469 int handle_notification_thread_client_disconnect_all(
3470 struct notification_thread_state
*state
)
3472 struct cds_lfht_iter iter
;
3473 struct notification_client
*client
;
3474 bool error_encoutered
= false;
3477 DBG("Closing all client connections");
3478 cds_lfht_for_each_entry(state
->client_socket_ht
, &iter
, client
,
3479 client_socket_ht_node
) {
3482 ret
= notification_thread_client_disconnect(
3485 error_encoutered
= true;
3489 return error_encoutered
? 1 : 0;
3492 int handle_notification_thread_trigger_unregister_all(
3493 struct notification_thread_state
*state
)
3495 bool error_occurred
= false;
3496 struct cds_lfht_iter iter
;
3497 struct lttng_trigger_ht_element
*trigger_ht_element
;
3500 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
3502 int ret
= handle_notification_thread_command_unregister_trigger(
3503 state
, trigger_ht_element
->trigger
, NULL
);
3505 error_occurred
= true;
3509 return error_occurred
? -1 : 0;
3513 int client_handle_transmission_status(
3514 struct notification_client
*client
,
3515 enum client_transmission_status transmission_status
,
3516 struct notification_thread_state
*state
)
3520 switch (transmission_status
) {
3521 case CLIENT_TRANSMISSION_STATUS_COMPLETE
:
3522 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3523 CLIENT_POLL_MASK_IN
);
3529 case CLIENT_TRANSMISSION_STATUS_QUEUED
:
3531 * We want to be notified whenever there is buffer space
3532 * available to send the rest of the payload.
3534 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3535 CLIENT_POLL_MASK_IN_OUT
);
3540 case CLIENT_TRANSMISSION_STATUS_FAIL
:
3541 ret
= notification_thread_client_disconnect(client
, state
);
3546 case CLIENT_TRANSMISSION_STATUS_ERROR
:
3556 /* Client lock must be acquired by caller. */
3558 enum client_transmission_status
client_flush_outgoing_queue(
3559 struct notification_client
*client
)
3562 size_t to_send_count
;
3563 enum client_transmission_status status
;
3564 struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3565 &client
->communication
.outbound
.payload
, 0, -1);
3566 const int fds_to_send_count
=
3567 lttng_payload_view_get_fd_handle_count(&pv
);
3569 ASSERT_LOCKED(client
->lock
);
3571 if (!client
->communication
.active
) {
3572 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3576 if (pv
.buffer
.size
== 0) {
3578 * If both data and fds are equal to zero, we are in an invalid
3581 LTTNG_ASSERT(fds_to_send_count
!= 0);
3586 to_send_count
= pv
.buffer
.size
;
3587 DBG("Flushing client (socket fd = %i) outgoing queue",
3590 ret
= lttcomm_send_unix_sock_non_block(client
->socket
,
3593 if ((ret
>= 0 && ret
< to_send_count
)) {
3594 DBG("Client (socket fd = %i) outgoing queue could not be completely flushed",
3596 to_send_count
-= std::max(ret
, (ssize_t
) 0);
3598 memmove(client
->communication
.outbound
.payload
.buffer
.data
,
3600 pv
.buffer
.size
- to_send_count
,
3602 ret
= lttng_dynamic_buffer_set_size(
3603 &client
->communication
.outbound
.payload
.buffer
,
3609 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3611 } else if (ret
< 0) {
3612 /* Generic error, disable the client's communication. */
3613 ERR("Failed to flush outgoing queue, disconnecting client (socket fd = %i)",
3615 client
->communication
.active
= false;
3616 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3620 * No error and flushed the queue completely.
3622 * The payload buffer size is used later to
3623 * check if there is notifications queued. So albeit that the
3624 * direct caller knows that the transmission is complete, we
3625 * need to set the buffer size to zero.
3627 ret
= lttng_dynamic_buffer_set_size(
3628 &client
->communication
.outbound
.payload
.buffer
, 0);
3635 /* No fds to send, transmission is complete. */
3636 if (fds_to_send_count
== 0) {
3637 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3641 ret
= lttcomm_send_payload_view_fds_unix_sock_non_block(
3642 client
->socket
, &pv
);
3644 /* Generic error, disable the client's communication. */
3645 ERR("Failed to flush outgoing fds queue, disconnecting client (socket fd = %i)",
3647 client
->communication
.active
= false;
3648 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3650 } else if (ret
== 0) {
3651 /* Nothing could be sent. */
3652 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3654 /* Fd passing is an all or nothing kind of thing. */
3655 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3657 * The payload _fd_array count is used later to
3658 * check if there is notifications queued. So although the
3659 * direct caller knows that the transmission is complete, we
3660 * need to clear the _fd_array for the queuing check.
3662 lttng_dynamic_pointer_array_clear(
3663 &client
->communication
.outbound
.payload
3668 if (status
== CLIENT_TRANSMISSION_STATUS_COMPLETE
) {
3669 client
->communication
.outbound
.queued_command_reply
= false;
3670 client
->communication
.outbound
.dropped_notification
= false;
3671 lttng_payload_clear(&client
->communication
.outbound
.payload
);
3676 return CLIENT_TRANSMISSION_STATUS_ERROR
;
3680 bool client_has_outbound_data_left(
3681 const struct notification_client
*client
)
3683 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3684 &client
->communication
.outbound
.payload
, 0, -1);
3685 const bool has_data
= pv
.buffer
.size
!= 0;
3686 const bool has_fds
= lttng_payload_view_get_fd_handle_count(&pv
);
3688 return has_data
|| has_fds
;
3691 /* Client lock must _not_ be held by the caller. */
3693 int client_send_command_reply(struct notification_client
*client
,
3694 struct notification_thread_state
*state
,
3695 enum lttng_notification_channel_status status
)
3698 struct lttng_notification_channel_command_reply reply
= {
3699 .status
= (int8_t) status
,
3701 struct lttng_notification_channel_message msg
= {
3702 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY
,
3703 .size
= sizeof(reply
),
3705 char buffer
[sizeof(msg
) + sizeof(reply
)];
3706 enum client_transmission_status transmission_status
;
3708 memcpy(buffer
, &msg
, sizeof(msg
));
3709 memcpy(buffer
+ sizeof(msg
), &reply
, sizeof(reply
));
3710 DBG("Send command reply (%i)", (int) status
);
3712 pthread_mutex_lock(&client
->lock
);
3713 if (client
->communication
.outbound
.queued_command_reply
) {
3714 /* Protocol error. */
3718 /* Enqueue buffer to outgoing queue and flush it. */
3719 ret
= lttng_dynamic_buffer_append(
3720 &client
->communication
.outbound
.payload
.buffer
,
3721 buffer
, sizeof(buffer
));
3726 transmission_status
= client_flush_outgoing_queue(client
);
3728 if (client_has_outbound_data_left(client
)) {
3729 /* Queue could not be emptied. */
3730 client
->communication
.outbound
.queued_command_reply
= true;
3733 pthread_mutex_unlock(&client
->lock
);
3734 ret
= client_handle_transmission_status(
3735 client
, transmission_status
, state
);
3742 pthread_mutex_unlock(&client
->lock
);
3748 int client_handle_message_unknown(struct notification_client
*client
,
3749 struct notification_thread_state
*state
)
3753 * Receiving message header. The function will be called again
3754 * once the rest of the message as been received and can be
3757 const struct lttng_notification_channel_message
*msg
;
3759 LTTNG_ASSERT(sizeof(*msg
) == client
->communication
.inbound
.payload
.buffer
.size
);
3760 msg
= (const struct lttng_notification_channel_message
*)
3761 client
->communication
.inbound
.payload
.buffer
.data
;
3763 if (msg
->size
== 0 ||
3764 msg
->size
> DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE
) {
3765 ERR("Invalid notification channel message: length = %u",
3771 switch (msg
->type
) {
3772 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3773 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3774 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3778 ERR("Invalid notification channel message: unexpected message type");
3782 client
->communication
.inbound
.bytes_to_receive
= msg
->size
;
3783 client
->communication
.inbound
.fds_to_receive
= msg
->fds
;
3784 client
->communication
.inbound
.msg_type
=
3785 (enum lttng_notification_channel_message_type
) msg
->type
;
3786 ret
= lttng_dynamic_buffer_set_size(
3787 &client
->communication
.inbound
.payload
.buffer
, msg
->size
);
3789 /* msg is not valid anymore due to lttng_dynamic_buffer_set_size. */
3796 int client_handle_message_handshake(struct notification_client
*client
,
3797 struct notification_thread_state
*state
)
3800 struct lttng_notification_channel_command_handshake
*handshake_client
;
3801 const struct lttng_notification_channel_command_handshake handshake_reply
= {
3802 .major
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
,
3803 .minor
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR
,
3805 const struct lttng_notification_channel_message msg_header
= {
3806 .type
= LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
,
3807 .size
= sizeof(handshake_reply
),
3809 enum lttng_notification_channel_status status
=
3810 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3811 char send_buffer
[sizeof(msg_header
) + sizeof(handshake_reply
)];
3813 memcpy(send_buffer
, &msg_header
, sizeof(msg_header
));
3814 memcpy(send_buffer
+ sizeof(msg_header
), &handshake_reply
,
3815 sizeof(handshake_reply
));
3818 (struct lttng_notification_channel_command_handshake
*)
3819 client
->communication
.inbound
.payload
.buffer
3821 client
->major
= handshake_client
->major
;
3822 client
->minor
= handshake_client
->minor
;
3823 if (!client
->communication
.inbound
.creds_received
) {
3824 ERR("No credentials received from client");
3829 client
->uid
= LTTNG_SOCK_GET_UID_CRED(
3830 &client
->communication
.inbound
.creds
);
3831 client
->gid
= LTTNG_SOCK_GET_GID_CRED(
3832 &client
->communication
.inbound
.creds
);
3833 client
->is_sessiond
= LTTNG_SOCK_GET_PID_CRED(&client
->communication
.inbound
.creds
) == getpid();
3834 DBG("Received handshake from client: uid = %u, gid = %u, protocol version = %i.%i, client is sessiond = %s",
3835 client
->uid
, client
->gid
, (int) client
->major
,
3836 (int) client
->minor
,
3837 client
->is_sessiond
? "true" : "false");
3839 if (handshake_client
->major
!=
3840 LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
) {
3841 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION
;
3844 pthread_mutex_lock(&client
->lock
);
3845 /* Outgoing queue will be flushed when the command reply is sent. */
3846 ret
= lttng_dynamic_buffer_append(
3847 &client
->communication
.outbound
.payload
.buffer
, send_buffer
,
3848 sizeof(send_buffer
));
3850 ERR("Failed to send protocol version to notification channel client");
3854 client
->validated
= true;
3855 client
->communication
.active
= true;
3856 pthread_mutex_unlock(&client
->lock
);
3858 /* Set reception state to receive the next message header. */
3859 ret
= client_reset_inbound_state(client
);
3861 ERR("Failed to reset client communication's inbound state");
3865 /* Flushes the outgoing queue. */
3866 ret
= client_send_command_reply(client
, state
, status
);
3868 ERR("Failed to send reply to notification channel client");
3874 pthread_mutex_unlock(&client
->lock
);
3880 int client_handle_message_subscription(
3881 struct notification_client
*client
,
3882 enum lttng_notification_channel_message_type msg_type
,
3883 struct notification_thread_state
*state
)
3886 struct lttng_condition
*condition
;
3887 enum lttng_notification_channel_status status
=
3888 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3889 struct lttng_payload_view condition_view
=
3890 lttng_payload_view_from_payload(
3891 &client
->communication
.inbound
.payload
,
3893 size_t expected_condition_size
;
3896 * No need to lock client to sample the inbound state as the only
3897 * other thread accessing clients (action executor) only uses the
3900 expected_condition_size
= client
->communication
.inbound
.payload
.buffer
.size
;
3901 ret
= lttng_condition_create_from_payload(&condition_view
, &condition
);
3902 if (ret
!= expected_condition_size
) {
3903 ERR("Malformed condition received from client");
3907 /* Ownership of condition is always transferred. */
3908 if (msg_type
== LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
) {
3909 ret
= notification_thread_client_subscribe(
3910 client
, condition
, state
, &status
);
3912 ret
= notification_thread_client_unsubscribe(
3913 client
, condition
, state
, &status
);
3920 /* Set reception state to receive the next message header. */
3921 ret
= client_reset_inbound_state(client
);
3923 ERR("Failed to reset client communication's inbound state");
3927 ret
= client_send_command_reply(client
, state
, status
);
3929 ERR("Failed to send reply to notification channel client");
3938 int client_dispatch_message(struct notification_client
*client
,
3939 struct notification_thread_state
*state
)
3943 if (client
->communication
.inbound
.msg_type
!=
3944 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
&&
3945 client
->communication
.inbound
.msg_type
!=
3946 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
&&
3947 !client
->validated
) {
3948 WARN("client attempted a command before handshake");
3953 switch (client
->communication
.inbound
.msg_type
) {
3954 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
:
3956 ret
= client_handle_message_unknown(client
, state
);
3959 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3961 ret
= client_handle_message_handshake(client
, state
);
3964 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3965 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3967 ret
= client_handle_message_subscription(client
,
3968 client
->communication
.inbound
.msg_type
, state
);
3978 /* Incoming data from client. */
3979 int handle_notification_thread_client_in(
3980 struct notification_thread_state
*state
, int socket
)
3983 struct notification_client
*client
;
3988 client
= get_client_from_socket(socket
, state
);
3990 /* Internal error, abort. */
3995 if (client
->communication
.inbound
.bytes_to_receive
== 0 &&
3996 client
->communication
.inbound
.fds_to_receive
!= 0) {
3997 /* Only FDs left to receive. */
4001 offset
= client
->communication
.inbound
.payload
.buffer
.size
-
4002 client
->communication
.inbound
.bytes_to_receive
;
4003 if (client
->communication
.inbound
.expect_creds
) {
4004 recv_ret
= lttcomm_recv_creds_unix_sock(socket
,
4005 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
4006 client
->communication
.inbound
.bytes_to_receive
,
4007 &client
->communication
.inbound
.creds
);
4009 client
->communication
.inbound
.expect_creds
= false;
4010 client
->communication
.inbound
.creds_received
= true;
4013 recv_ret
= lttcomm_recv_unix_sock_non_block(socket
,
4014 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
4015 client
->communication
.inbound
.bytes_to_receive
);
4017 if (recv_ret
>= 0) {
4018 client
->communication
.inbound
.bytes_to_receive
-= recv_ret
;
4020 goto error_disconnect_client
;
4023 if (client
->communication
.inbound
.bytes_to_receive
!= 0) {
4024 /* Message incomplete wait for more data. */
4030 LTTNG_ASSERT(client
->communication
.inbound
.bytes_to_receive
== 0);
4033 if (client
->communication
.inbound
.fds_to_receive
!= 0) {
4034 ret
= lttcomm_recv_payload_fds_unix_sock_non_block(
4036 client
->communication
.inbound
.fds_to_receive
,
4037 &client
->communication
.inbound
.payload
);
4040 * Fds received. non blocking fds passing is all
4043 ssize_t expected_size
;
4045 expected_size
= sizeof(int) *
4046 client
->communication
.inbound
4048 LTTNG_ASSERT(ret
== expected_size
);
4049 client
->communication
.inbound
.fds_to_receive
= 0;
4050 } else if (ret
== 0) {
4051 /* Received nothing. */
4055 goto error_disconnect_client
;
4059 /* At this point the message is complete.*/
4060 LTTNG_ASSERT(client
->communication
.inbound
.bytes_to_receive
== 0 &&
4061 client
->communication
.inbound
.fds_to_receive
== 0);
4062 ret
= client_dispatch_message(client
, state
);
4065 * Only returns an error if this client must be
4068 goto error_disconnect_client
;
4075 error_disconnect_client
:
4076 ret
= notification_thread_client_disconnect(client
, state
);
4080 /* Client ready to receive outgoing data. */
4081 int handle_notification_thread_client_out(
4082 struct notification_thread_state
*state
, int socket
)
4085 struct notification_client
*client
;
4086 enum client_transmission_status transmission_status
;
4089 client
= get_client_from_socket(socket
, state
);
4091 /* Internal error, abort. */
4096 pthread_mutex_lock(&client
->lock
);
4097 transmission_status
= client_flush_outgoing_queue(client
);
4098 pthread_mutex_unlock(&client
->lock
);
4100 ret
= client_handle_transmission_status(
4101 client
, transmission_status
, state
);
4111 bool evaluate_buffer_usage_condition(const struct lttng_condition
*condition
,
4112 const struct channel_state_sample
*sample
,
4113 uint64_t buffer_capacity
)
4115 bool result
= false;
4117 enum lttng_condition_type condition_type
;
4118 const struct lttng_condition_buffer_usage
*use_condition
= container_of(
4119 condition
, struct lttng_condition_buffer_usage
,
4122 if (use_condition
->threshold_bytes
.set
) {
4123 threshold
= use_condition
->threshold_bytes
.value
;
4126 * Threshold was expressed as a ratio.
4128 * TODO the threshold (in bytes) of conditions expressed
4129 * as a ratio of total buffer size could be cached to
4130 * forego this double-multiplication or it could be performed
4131 * as fixed-point math.
4133 * Note that caching should accommodates the case where the
4134 * condition applies to multiple channels (i.e. don't assume
4135 * that all channels matching my_chann* have the same size...)
4137 threshold
= (uint64_t) (use_condition
->threshold_ratio
.value
*
4138 (double) buffer_capacity
);
4141 condition_type
= lttng_condition_get_type(condition
);
4142 if (condition_type
== LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
) {
4143 DBG("Low buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4144 threshold
, sample
->highest_usage
);
4147 * The low condition should only be triggered once _all_ of the
4148 * streams in a channel have gone below the "low" threshold.
4150 if (sample
->highest_usage
<= threshold
) {
4154 DBG("High buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4155 threshold
, sample
->highest_usage
);
4158 * For high buffer usage scenarios, we want to trigger whenever
4159 * _any_ of the streams has reached the "high" threshold.
4161 if (sample
->highest_usage
>= threshold
) {
4170 bool evaluate_session_consumed_size_condition(
4171 const struct lttng_condition
*condition
,
4172 uint64_t session_consumed_size
)
4175 const struct lttng_condition_session_consumed_size
*size_condition
=
4176 container_of(condition
,
4177 struct lttng_condition_session_consumed_size
,
4180 threshold
= size_condition
->consumed_threshold_bytes
.value
;
4181 DBG("Session consumed size condition being evaluated: threshold = %" PRIu64
", current size = %" PRIu64
,
4182 threshold
, session_consumed_size
);
4183 return session_consumed_size
>= threshold
;
4187 int evaluate_buffer_condition(const struct lttng_condition
*condition
,
4188 struct lttng_evaluation
**evaluation
,
4189 const struct notification_thread_state
*state
,
4190 const struct channel_state_sample
*previous_sample
,
4191 const struct channel_state_sample
*latest_sample
,
4192 uint64_t previous_session_consumed_total
,
4193 uint64_t latest_session_consumed_total
,
4194 struct channel_info
*channel_info
)
4197 enum lttng_condition_type condition_type
;
4198 const bool previous_sample_available
= !!previous_sample
;
4199 bool previous_sample_result
= false;
4200 bool latest_sample_result
;
4202 condition_type
= lttng_condition_get_type(condition
);
4204 switch (condition_type
) {
4205 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4206 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4207 if (caa_likely(previous_sample_available
)) {
4208 previous_sample_result
=
4209 evaluate_buffer_usage_condition(condition
,
4210 previous_sample
, channel_info
->capacity
);
4212 latest_sample_result
= evaluate_buffer_usage_condition(
4213 condition
, latest_sample
,
4214 channel_info
->capacity
);
4216 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
4217 if (caa_likely(previous_sample_available
)) {
4218 previous_sample_result
=
4219 evaluate_session_consumed_size_condition(
4221 previous_session_consumed_total
);
4223 latest_sample_result
=
4224 evaluate_session_consumed_size_condition(
4226 latest_session_consumed_total
);
4229 /* Unknown condition type; internal error. */
4233 if (!latest_sample_result
||
4234 (previous_sample_result
== latest_sample_result
)) {
4236 * Only trigger on a condition evaluation transition.
4238 * NOTE: This edge-triggered logic may not be appropriate for
4239 * future condition types.
4244 if (!evaluation
|| !latest_sample_result
) {
4248 switch (condition_type
) {
4249 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4250 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4251 *evaluation
= lttng_evaluation_buffer_usage_create(
4253 latest_sample
->highest_usage
,
4254 channel_info
->capacity
);
4256 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
4257 *evaluation
= lttng_evaluation_session_consumed_size_create(
4258 latest_session_consumed_total
);
4273 int client_notification_overflow(struct notification_client
*client
)
4276 const struct lttng_notification_channel_message msg
= {
4277 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED
,
4280 ASSERT_LOCKED(client
->lock
);
4282 DBG("Dropping notification addressed to client (socket fd = %i)",
4284 if (client
->communication
.outbound
.dropped_notification
) {
4286 * The client already has a "notification dropped" message
4287 * in its outgoing queue. Nothing to do since all
4288 * of those messages are coalesced.
4293 client
->communication
.outbound
.dropped_notification
= true;
4294 ret
= lttng_dynamic_buffer_append(
4295 &client
->communication
.outbound
.payload
.buffer
, &msg
,
4298 PERROR("Failed to enqueue \"dropped notification\" message in client's (socket fd = %i) outgoing queue",
4305 static int client_handle_transmission_status_wrapper(
4306 struct notification_client
*client
,
4307 enum client_transmission_status status
,
4310 return client_handle_transmission_status(client
, status
,
4311 (struct notification_thread_state
*) user_data
);
4315 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
4316 const struct lttng_evaluation
*evaluation
,
4317 struct notification_client_list
* client_list
,
4318 struct notification_thread_state
*state
,
4319 uid_t object_uid
, gid_t object_gid
)
4321 const struct lttng_credentials creds
= {
4322 .uid
= LTTNG_OPTIONAL_INIT_VALUE(object_uid
),
4323 .gid
= LTTNG_OPTIONAL_INIT_VALUE(object_gid
),
4326 return notification_client_list_send_evaluation(client_list
,
4327 trigger
, evaluation
,
4329 client_handle_transmission_status_wrapper
, state
);
4333 * Permission checks relative to notification channel clients are performed
4334 * here. Notice how object, client, and trigger credentials are involved in
4337 * The `object` credentials are the credentials associated with the "subject"
4338 * of a condition. For instance, a `rotation completed` condition applies
4339 * to a session. When that condition is met, it will produce an evaluation
4340 * against a session. Hence, in this case, the `object` credentials are the
4341 * credentials of the "subject" session.
4343 * The `trigger` credentials are the credentials of the user that registered the
4346 * The `client` credentials are the credentials of the user that created a given
4347 * notification channel.
4349 * In terms of visibility, it is expected that non-privilieged users can only
4350 * register triggers against "their" objects (their own sessions and
4351 * applications they are allowed to interact with). They can then open a
4352 * notification channel and subscribe to notifications associated with those
4355 * As for privilieged users, they can register triggers against the objects of
4356 * other users. They can then subscribe to the notifications associated to their
4357 * triggers. Privilieged users _can't_ subscribe to the notifications of
4358 * triggers owned by other users; they must create their own triggers.
4360 * This is more a concern of usability than security. It would be difficult for
4361 * a root user reliably subscribe to a specific set of conditions without
4362 * interference from external users (those could, for instance, unregister
4365 int notification_client_list_send_evaluation(
4366 struct notification_client_list
*client_list
,
4367 const struct lttng_trigger
*trigger
,
4368 const struct lttng_evaluation
*evaluation
,
4369 const struct lttng_credentials
*source_object_creds
,
4370 report_client_transmission_result_cb client_report
,
4374 struct lttng_payload msg_payload
;
4375 struct notification_client_list_element
*client_list_element
, *tmp
;
4376 const struct lttng_notification notification
= {
4377 .trigger
= (struct lttng_trigger
*) trigger
,
4378 .evaluation
= (struct lttng_evaluation
*) evaluation
,
4380 struct lttng_notification_channel_message msg_header
= {
4381 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION
,
4383 const struct lttng_credentials
*trigger_creds
=
4384 lttng_trigger_get_credentials(trigger
);
4386 lttng_payload_init(&msg_payload
);
4388 ret
= lttng_dynamic_buffer_append(&msg_payload
.buffer
, &msg_header
,
4389 sizeof(msg_header
));
4394 ret
= lttng_notification_serialize(¬ification
, &msg_payload
);
4396 ERR("Failed to serialize notification");
4401 /* Update payload size. */
4402 ((struct lttng_notification_channel_message
*) msg_payload
.buffer
.data
)
4403 ->size
= (uint32_t)(
4404 msg_payload
.buffer
.size
- sizeof(msg_header
));
4406 /* Update the payload number of fds. */
4408 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
4409 &msg_payload
, 0, -1);
4411 ((struct lttng_notification_channel_message
*)
4412 msg_payload
.buffer
.data
)->fds
= (uint32_t)
4413 lttng_payload_view_get_fd_handle_count(&pv
);
4416 pthread_mutex_lock(&client_list
->lock
);
4417 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4418 &client_list
->clients_list
, node
) {
4419 enum client_transmission_status transmission_status
;
4420 struct notification_client
*client
=
4421 client_list_element
->client
;
4424 pthread_mutex_lock(&client
->lock
);
4425 if (!client
->communication
.active
) {
4427 * Skip inactive client (protocol error or
4430 DBG("Skipping client at it is marked as inactive");
4434 if (lttng_trigger_is_hidden(trigger
) && !client
->is_sessiond
) {
4436 * Notifications resulting from an hidden trigger are
4437 * only sent to the session daemon.
4439 DBG("Skipping client as the trigger is hidden and the client is not the session daemon");
4443 if (source_object_creds
) {
4444 if (client
->uid
!= lttng_credentials_get_uid(source_object_creds
) &&
4445 client
->gid
!= lttng_credentials_get_gid(source_object_creds
) &&
4448 * Client is not allowed to monitor this
4451 DBG("Skipping client at it does not have the object permission to receive notification for this trigger");
4456 if (client
->uid
!= lttng_credentials_get_uid(trigger_creds
)) {
4457 DBG("Skipping client at it does not have the permission to receive notification for this trigger");
4461 DBG("Sending notification to client (fd = %i, %zu bytes)",
4462 client
->socket
, msg_payload
.buffer
.size
);
4464 if (client_has_outbound_data_left(client
)) {
4466 * Outgoing data is already buffered for this client;
4467 * drop the notification and enqueue a "dropped
4468 * notification" message if this is the first dropped
4469 * notification since the socket spilled-over to the
4472 ret
= client_notification_overflow(client
);
4479 ret
= lttng_payload_copy(&msg_payload
, &client
->communication
.outbound
.payload
);
4485 transmission_status
= client_flush_outgoing_queue(client
);
4486 pthread_mutex_unlock(&client
->lock
);
4487 ret
= client_report(client
, transmission_status
, user_data
);
4490 goto end_unlock_list
;
4496 pthread_mutex_unlock(&client
->lock
);
4499 goto end_unlock_list
;
4505 pthread_mutex_unlock(&client_list
->lock
);
4507 lttng_payload_reset(&msg_payload
);
4512 struct lttng_event_notifier_notification
*recv_one_event_notifier_notification(
4513 int notification_pipe_read_fd
, enum lttng_domain_type domain
)
4517 struct lttng_event_notifier_notification
*notification
= NULL
;
4518 char *capture_buffer
= NULL
;
4519 size_t capture_buffer_size
;
4520 void *reception_buffer
;
4521 size_t reception_size
;
4523 struct lttng_ust_abi_event_notifier_notification ust_notification
;
4524 struct lttng_kernel_abi_event_notifier_notification kernel_notification
;
4526 /* Init lttng_event_notifier_notification */
4528 case LTTNG_DOMAIN_UST
:
4529 reception_buffer
= (void *) &ust_notification
;
4530 reception_size
= sizeof(ust_notification
);
4532 case LTTNG_DOMAIN_KERNEL
:
4533 reception_buffer
= (void *) &kernel_notification
;
4534 reception_size
= sizeof(kernel_notification
);
4541 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4542 * ensuring that read/write of tracer notifications are atomic.
4544 ret
= lttng_read(notification_pipe_read_fd
, reception_buffer
,
4546 if (ret
!= reception_size
) {
4547 PERROR("Failed to read from event source notification pipe: fd = %d, size to read = %zu, ret = %d",
4548 notification_pipe_read_fd
, reception_size
, ret
);
4554 case LTTNG_DOMAIN_UST
:
4555 token
= ust_notification
.token
;
4556 capture_buffer_size
= ust_notification
.capture_buf_size
;
4558 case LTTNG_DOMAIN_KERNEL
:
4559 token
= kernel_notification
.token
;
4560 capture_buffer_size
= kernel_notification
.capture_buf_size
;
4566 if (capture_buffer_size
== 0) {
4567 capture_buffer
= NULL
;
4571 if (capture_buffer_size
> MAX_CAPTURE_SIZE
) {
4572 ERR("Event notifier has a capture payload size which exceeds the maximum allowed size: capture_payload_size = %zu bytes, max allowed size = %d bytes",
4573 capture_buffer_size
, MAX_CAPTURE_SIZE
);
4577 capture_buffer
= (char *) zmalloc(capture_buffer_size
);
4578 if (!capture_buffer
) {
4579 ERR("Failed to allocate capture buffer");
4583 /* Fetch additional payload (capture). */
4584 ret
= lttng_read(notification_pipe_read_fd
, capture_buffer
, capture_buffer_size
);
4585 if (ret
!= capture_buffer_size
) {
4586 ERR("Failed to read from event source pipe (fd = %i)",
4587 notification_pipe_read_fd
);
4592 notification
= lttng_event_notifier_notification_create(token
, domain
,
4593 capture_buffer
, capture_buffer_size
);
4594 if (notification
== NULL
) {
4599 * Ownership transfered to the lttng_event_notifier_notification object.
4601 capture_buffer
= NULL
;
4604 free(capture_buffer
);
4605 return notification
;
4609 int dispatch_one_event_notifier_notification(struct notification_thread_state
*state
,
4610 struct lttng_event_notifier_notification
*notification
)
4612 struct cds_lfht_node
*node
;
4613 struct cds_lfht_iter iter
;
4614 struct notification_trigger_tokens_ht_element
*element
;
4615 struct lttng_evaluation
*evaluation
= NULL
;
4616 enum action_executor_status executor_status
;
4617 struct notification_client_list
*client_list
= NULL
;
4619 unsigned int capture_count
= 0;
4621 /* Find triggers associated with this token. */
4623 cds_lfht_lookup(state
->trigger_tokens_ht
,
4624 hash_key_u64(¬ification
->tracer_token
, lttng_ht_seed
),
4625 match_trigger_token
, ¬ification
->tracer_token
, &iter
);
4626 node
= cds_lfht_iter_get_node(&iter
);
4627 if (caa_unlikely(!node
)) {
4629 * This is not an error, slow consumption of the tracer
4630 * notifications can lead to situations where a trigger is
4631 * removed but we still get tracer notifications matching a
4632 * trigger that no longer exists.
4638 element
= caa_container_of(node
,
4639 struct notification_trigger_tokens_ht_element
,
4642 if (lttng_condition_event_rule_matches_get_capture_descriptor_count(
4643 lttng_trigger_get_const_condition(element
->trigger
),
4644 &capture_count
) != LTTNG_CONDITION_STATUS_OK
) {
4645 ERR("Failed to get capture count");
4650 if (!notification
->capture_buffer
&& capture_count
!= 0) {
4651 ERR("Expected capture but capture buffer is null");
4656 evaluation
= lttng_evaluation_event_rule_matches_create(
4657 container_of(lttng_trigger_get_const_condition(
4659 struct lttng_condition_event_rule_matches
,
4661 notification
->capture_buffer
,
4662 notification
->capture_buf_size
, false);
4664 if (evaluation
== NULL
) {
4665 ERR("Failed to create event rule matches evaluation while creating and enqueuing action executor job");
4670 client_list
= get_client_list_from_condition(state
,
4671 lttng_trigger_get_const_condition(element
->trigger
));
4672 executor_status
= action_executor_enqueue_trigger(state
->executor
,
4673 element
->trigger
, evaluation
, NULL
, client_list
);
4674 switch (executor_status
) {
4675 case ACTION_EXECUTOR_STATUS_OK
:
4678 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4680 struct notification_client_list_element
*client_list_element
,
4684 * Not a fatal error; this is expected and simply means the
4685 * executor has too much work queued already.
4689 /* No clients subscribed to notifications for this trigger. */
4694 /* Warn clients that a notification (or more) was dropped. */
4695 pthread_mutex_lock(&client_list
->lock
);
4696 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4697 &client_list
->clients_list
, node
) {
4698 enum client_transmission_status transmission_status
;
4699 struct notification_client
*client
=
4700 client_list_element
->client
;
4702 pthread_mutex_lock(&client
->lock
);
4703 ret
= client_notification_overflow(client
);
4709 transmission_status
=
4710 client_flush_outgoing_queue(client
);
4711 ret
= client_handle_transmission_status(
4712 client
, transmission_status
, state
);
4718 pthread_mutex_unlock(&client
->lock
);
4724 pthread_mutex_unlock(&client_list
->lock
);
4727 case ACTION_EXECUTOR_STATUS_INVALID
:
4728 case ACTION_EXECUTOR_STATUS_ERROR
:
4729 /* Fatal error, shut down everything. */
4730 ERR("Fatal error encoutered while enqueuing action to the action executor");
4734 /* Unhandled error. */
4739 notification_client_list_put(client_list
);
4746 int handle_one_event_notifier_notification(
4747 struct notification_thread_state
*state
,
4748 int pipe
, enum lttng_domain_type domain
)
4751 struct lttng_event_notifier_notification
*notification
= NULL
;
4753 notification
= recv_one_event_notifier_notification(pipe
, domain
);
4754 if (notification
== NULL
) {
4755 /* Reception failed, don't consider it fatal. */
4756 ERR("Error receiving an event notifier notification from tracer: fd = %i, domain = %s",
4757 pipe
, lttng_domain_type_str(domain
));
4761 ret
= dispatch_one_event_notifier_notification(state
, notification
);
4763 ERR("Error dispatching an event notifier notification from tracer: fd = %i, domain = %s",
4764 pipe
, lttng_domain_type_str(domain
));
4769 lttng_event_notifier_notification_destroy(notification
);
4773 int handle_notification_thread_event_notification(struct notification_thread_state
*state
,
4774 int pipe
, enum lttng_domain_type domain
)
4776 return handle_one_event_notifier_notification(state
, pipe
, domain
);
4779 int handle_notification_thread_channel_sample(
4780 struct notification_thread_state
*state
, int pipe
,
4781 enum lttng_domain_type domain
)
4784 struct lttcomm_consumer_channel_monitor_msg sample_msg
;
4785 struct channel_info
*channel_info
;
4786 struct cds_lfht_node
*node
;
4787 struct cds_lfht_iter iter
;
4788 struct lttng_channel_trigger_list
*trigger_list
;
4789 struct lttng_trigger_list_element
*trigger_list_element
;
4790 bool previous_sample_available
= false;
4791 struct channel_state_sample previous_sample
, latest_sample
;
4792 uint64_t previous_session_consumed_total
, latest_session_consumed_total
;
4793 struct lttng_credentials channel_creds
;
4796 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4797 * ensuring that read/write of sampling messages are atomic.
4799 ret
= lttng_read(pipe
, &sample_msg
, sizeof(sample_msg
));
4800 if (ret
!= sizeof(sample_msg
)) {
4801 ERR("Failed to read from monitoring pipe (fd = %i)",
4808 latest_sample
.key
.key
= sample_msg
.key
;
4809 latest_sample
.key
.domain
= domain
;
4810 latest_sample
.highest_usage
= sample_msg
.highest
;
4811 latest_sample
.lowest_usage
= sample_msg
.lowest
;
4812 latest_sample
.channel_total_consumed
= sample_msg
.total_consumed
;
4816 /* Retrieve the channel's informations */
4817 cds_lfht_lookup(state
->channels_ht
,
4818 hash_channel_key(&latest_sample
.key
),
4822 node
= cds_lfht_iter_get_node(&iter
);
4823 if (caa_unlikely(!node
)) {
4825 * Not an error since the consumer can push a sample to the pipe
4826 * and the rest of the session daemon could notify us of the
4827 * channel's destruction before we get a chance to process that
4830 DBG("Received a sample for an unknown channel from consumerd, key = %" PRIu64
" in %s domain",
4831 latest_sample
.key
.key
,
4832 lttng_domain_type_str(domain
));
4835 channel_info
= caa_container_of(node
, struct channel_info
,
4837 DBG("Handling channel sample for channel %s (key = %" PRIu64
") in session %s (highest usage = %" PRIu64
", lowest usage = %" PRIu64
", total consumed = %" PRIu64
")",
4839 latest_sample
.key
.key
,
4840 channel_info
->session_info
->name
,
4841 latest_sample
.highest_usage
,
4842 latest_sample
.lowest_usage
,
4843 latest_sample
.channel_total_consumed
);
4845 previous_session_consumed_total
=
4846 channel_info
->session_info
->consumed_data_size
;
4848 /* Retrieve the channel's last sample, if it exists, and update it. */
4849 cds_lfht_lookup(state
->channel_state_ht
,
4850 hash_channel_key(&latest_sample
.key
),
4851 match_channel_state_sample
,
4854 node
= cds_lfht_iter_get_node(&iter
);
4855 if (caa_likely(node
)) {
4856 struct channel_state_sample
*stored_sample
;
4858 /* Update the sample stored. */
4859 stored_sample
= caa_container_of(node
,
4860 struct channel_state_sample
,
4861 channel_state_ht_node
);
4863 memcpy(&previous_sample
, stored_sample
,
4864 sizeof(previous_sample
));
4865 stored_sample
->highest_usage
= latest_sample
.highest_usage
;
4866 stored_sample
->lowest_usage
= latest_sample
.lowest_usage
;
4867 stored_sample
->channel_total_consumed
= latest_sample
.channel_total_consumed
;
4868 previous_sample_available
= true;
4870 latest_session_consumed_total
=
4871 previous_session_consumed_total
+
4872 (latest_sample
.channel_total_consumed
- previous_sample
.channel_total_consumed
);
4875 * This is the channel's first sample, allocate space for and
4876 * store the new sample.
4878 struct channel_state_sample
*stored_sample
;
4880 stored_sample
= (channel_state_sample
*) zmalloc(sizeof(*stored_sample
));
4881 if (!stored_sample
) {
4886 memcpy(stored_sample
, &latest_sample
, sizeof(*stored_sample
));
4887 cds_lfht_node_init(&stored_sample
->channel_state_ht_node
);
4888 cds_lfht_add(state
->channel_state_ht
,
4889 hash_channel_key(&stored_sample
->key
),
4890 &stored_sample
->channel_state_ht_node
);
4892 latest_session_consumed_total
=
4893 previous_session_consumed_total
+
4894 latest_sample
.channel_total_consumed
;
4897 channel_info
->session_info
->consumed_data_size
=
4898 latest_session_consumed_total
;
4900 /* Find triggers associated with this channel. */
4901 cds_lfht_lookup(state
->channel_triggers_ht
,
4902 hash_channel_key(&latest_sample
.key
),
4903 match_channel_trigger_list
,
4906 node
= cds_lfht_iter_get_node(&iter
);
4907 if (caa_likely(!node
)) {
4911 channel_creds
= (typeof(channel_creds
)) {
4912 .uid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->uid
),
4913 .gid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->gid
),
4916 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
4917 channel_triggers_ht_node
);
4918 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
4920 const struct lttng_condition
*condition
;
4921 struct lttng_trigger
*trigger
;
4922 struct notification_client_list
*client_list
= NULL
;
4923 struct lttng_evaluation
*evaluation
= NULL
;
4924 enum action_executor_status executor_status
;
4927 trigger
= trigger_list_element
->trigger
;
4928 condition
= lttng_trigger_get_const_condition(trigger
);
4929 LTTNG_ASSERT(condition
);
4932 * Check if any client is subscribed to the result of this
4935 client_list
= get_client_list_from_condition(state
, condition
);
4937 ret
= evaluate_buffer_condition(condition
, &evaluation
, state
,
4938 previous_sample_available
? &previous_sample
: NULL
,
4940 previous_session_consumed_total
,
4941 latest_session_consumed_total
,
4943 if (caa_unlikely(ret
)) {
4947 if (caa_likely(!evaluation
)) {
4952 * Ownership of `evaluation` transferred to the action executor
4953 * no matter the result.
4955 executor_status
= action_executor_enqueue_trigger(
4956 state
->executor
, trigger
, evaluation
,
4957 &channel_creds
, client_list
);
4959 switch (executor_status
) {
4960 case ACTION_EXECUTOR_STATUS_OK
:
4962 case ACTION_EXECUTOR_STATUS_ERROR
:
4963 case ACTION_EXECUTOR_STATUS_INVALID
:
4965 * TODO Add trigger identification (name/id) when
4966 * it is added to the API.
4968 ERR("Fatal error occurred while enqueuing action associated with buffer-condition trigger");
4971 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4973 * TODO Add trigger identification (name/id) when
4974 * it is added to the API.
4976 * Not a fatal error.
4978 WARN("No space left when enqueuing action associated with buffer-condition trigger");
4986 notification_client_list_put(client_list
);
4987 if (caa_unlikely(ret
)) {