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
)
1289 * The client object is not reachable by other threads, no need to lock
1292 if (client
->socket
>= 0) {
1293 (void) lttcomm_close_unix_sock(client
->socket
);
1294 client
->socket
= -1;
1296 client
->communication
.active
= false;
1297 lttng_payload_reset(&client
->communication
.inbound
.payload
);
1298 lttng_payload_reset(&client
->communication
.outbound
.payload
);
1299 pthread_mutex_destroy(&client
->lock
);
1300 call_rcu(&client
->rcu_node
, free_notification_client_rcu
);
1304 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1308 struct notification_client
*get_client_from_socket(int socket
,
1309 struct notification_thread_state
*state
)
1311 struct cds_lfht_iter iter
;
1312 struct cds_lfht_node
*node
;
1313 struct notification_client
*client
= NULL
;
1315 ASSERT_RCU_READ_LOCKED();
1317 cds_lfht_lookup(state
->client_socket_ht
,
1318 hash_client_socket(socket
),
1319 match_client_socket
,
1320 (void *) (unsigned long) socket
,
1322 node
= cds_lfht_iter_get_node(&iter
);
1327 client
= caa_container_of(node
, struct notification_client
,
1328 client_socket_ht_node
);
1334 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1338 struct notification_client
*get_client_from_id(notification_client_id id
,
1339 struct notification_thread_state
*state
)
1341 struct cds_lfht_iter iter
;
1342 struct cds_lfht_node
*node
;
1343 struct notification_client
*client
= NULL
;
1345 ASSERT_RCU_READ_LOCKED();
1347 cds_lfht_lookup(state
->client_id_ht
,
1352 node
= cds_lfht_iter_get_node(&iter
);
1357 client
= caa_container_of(node
, struct notification_client
,
1364 bool buffer_usage_condition_applies_to_channel(
1365 const struct lttng_condition
*condition
,
1366 const struct channel_info
*channel_info
)
1368 enum lttng_condition_status status
;
1369 enum lttng_domain_type condition_domain
;
1370 const char *condition_session_name
= NULL
;
1371 const char *condition_channel_name
= NULL
;
1373 status
= lttng_condition_buffer_usage_get_domain_type(condition
,
1375 LTTNG_ASSERT(status
== LTTNG_CONDITION_STATUS_OK
);
1376 if (channel_info
->key
.domain
!= condition_domain
) {
1380 status
= lttng_condition_buffer_usage_get_session_name(
1381 condition
, &condition_session_name
);
1382 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1384 status
= lttng_condition_buffer_usage_get_channel_name(
1385 condition
, &condition_channel_name
);
1386 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_channel_name
);
1388 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1391 if (strcmp(channel_info
->name
, condition_channel_name
)) {
1401 bool session_consumed_size_condition_applies_to_channel(
1402 const struct lttng_condition
*condition
,
1403 const struct channel_info
*channel_info
)
1405 enum lttng_condition_status status
;
1406 const char *condition_session_name
= NULL
;
1408 status
= lttng_condition_session_consumed_size_get_session_name(
1409 condition
, &condition_session_name
);
1410 LTTNG_ASSERT((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1412 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1422 bool trigger_applies_to_channel(const struct lttng_trigger
*trigger
,
1423 const struct channel_info
*channel_info
)
1425 const struct lttng_condition
*condition
;
1426 bool trigger_applies
;
1428 condition
= lttng_trigger_get_const_condition(trigger
);
1433 switch (lttng_condition_get_type(condition
)) {
1434 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
1435 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
1436 trigger_applies
= buffer_usage_condition_applies_to_channel(
1437 condition
, channel_info
);
1439 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
1440 trigger_applies
= session_consumed_size_condition_applies_to_channel(
1441 condition
, channel_info
);
1447 return trigger_applies
;
1452 /* Must be called with RCU read lock held. */
1454 struct lttng_session_trigger_list
*get_session_trigger_list(
1455 struct notification_thread_state
*state
,
1456 const char *session_name
)
1458 struct lttng_session_trigger_list
*list
= NULL
;
1459 struct cds_lfht_node
*node
;
1460 struct cds_lfht_iter iter
;
1462 ASSERT_RCU_READ_LOCKED();
1464 cds_lfht_lookup(state
->session_triggers_ht
,
1465 hash_key_str(session_name
, lttng_ht_seed
),
1466 match_session_trigger_list
,
1469 node
= cds_lfht_iter_get_node(&iter
);
1472 * Not an error, the list of triggers applying to that session
1473 * will be initialized when the session is created.
1475 DBG("No trigger list found for session \"%s\" as it is not yet known to the notification system",
1480 list
= caa_container_of(node
,
1481 struct lttng_session_trigger_list
,
1482 session_triggers_ht_node
);
1488 * Allocate an empty lttng_session_trigger_list for the session named
1491 * No ownership of 'session_name' is assumed by the session trigger list.
1492 * It is the caller's responsability to ensure the session name is alive
1493 * for as long as this list is.
1496 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
1497 const char *session_name
,
1498 struct cds_lfht
*session_triggers_ht
)
1500 struct lttng_session_trigger_list
*list
;
1502 list
= (lttng_session_trigger_list
*) zmalloc(sizeof(*list
));
1506 list
->session_name
= session_name
;
1507 CDS_INIT_LIST_HEAD(&list
->list
);
1508 cds_lfht_node_init(&list
->session_triggers_ht_node
);
1509 list
->session_triggers_ht
= session_triggers_ht
;
1512 /* Publish the list through the session_triggers_ht. */
1513 cds_lfht_add(session_triggers_ht
,
1514 hash_key_str(session_name
, lttng_ht_seed
),
1515 &list
->session_triggers_ht_node
);
1522 void free_session_trigger_list_rcu(struct rcu_head
*node
)
1524 free(caa_container_of(node
, struct lttng_session_trigger_list
,
1529 void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list
*list
)
1531 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1533 /* Empty the list element by element, and then free the list itself. */
1534 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1535 &list
->list
, node
) {
1536 cds_list_del(&trigger_list_element
->node
);
1537 free(trigger_list_element
);
1540 /* Unpublish the list from the session_triggers_ht. */
1541 cds_lfht_del(list
->session_triggers_ht
,
1542 &list
->session_triggers_ht_node
);
1544 call_rcu(&list
->rcu_node
, free_session_trigger_list_rcu
);
1548 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
1549 struct lttng_trigger
*trigger
)
1552 struct lttng_trigger_list_element
*new_element
=
1553 (lttng_trigger_list_element
*) zmalloc(sizeof(*new_element
));
1559 CDS_INIT_LIST_HEAD(&new_element
->node
);
1560 new_element
->trigger
= trigger
;
1561 cds_list_add(&new_element
->node
, &list
->list
);
1567 bool trigger_applies_to_session(const struct lttng_trigger
*trigger
,
1568 const char *session_name
)
1570 bool applies
= false;
1571 const struct lttng_condition
*condition
;
1573 condition
= lttng_trigger_get_const_condition(trigger
);
1574 switch (lttng_condition_get_type(condition
)) {
1575 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1576 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1578 enum lttng_condition_status condition_status
;
1579 const char *condition_session_name
;
1581 condition_status
= lttng_condition_session_rotation_get_session_name(
1582 condition
, &condition_session_name
);
1583 if (condition_status
!= LTTNG_CONDITION_STATUS_OK
) {
1584 ERR("Failed to retrieve session rotation condition's session name");
1588 LTTNG_ASSERT(condition_session_name
);
1589 applies
= !strcmp(condition_session_name
, session_name
);
1600 * Allocate and initialize an lttng_session_trigger_list which contains
1601 * all triggers that apply to the session named 'session_name'.
1603 * No ownership of 'session_name' is assumed by the session trigger list.
1604 * It is the caller's responsability to ensure the session name is alive
1605 * for as long as this list is.
1608 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
1609 const struct notification_thread_state
*state
,
1610 const char *session_name
)
1612 int trigger_count
= 0;
1613 struct lttng_session_trigger_list
*session_trigger_list
= NULL
;
1614 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1615 struct cds_lfht_iter iter
;
1617 session_trigger_list
= lttng_session_trigger_list_create(session_name
,
1618 state
->session_triggers_ht
);
1620 /* Add all triggers applying to the session named 'session_name'. */
1621 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1625 if (!trigger_applies_to_session(trigger_ht_element
->trigger
,
1630 ret
= lttng_session_trigger_list_add(session_trigger_list
,
1631 trigger_ht_element
->trigger
);
1639 DBG("Found %i triggers that apply to newly created session",
1641 return session_trigger_list
;
1643 lttng_session_trigger_list_destroy(session_trigger_list
);
1648 struct session_info
*find_or_create_session_info(
1649 struct notification_thread_state
*state
,
1650 const char *name
, uid_t uid
, gid_t gid
)
1652 struct session_info
*session
= NULL
;
1653 struct cds_lfht_node
*node
;
1654 struct cds_lfht_iter iter
;
1655 struct lttng_session_trigger_list
*trigger_list
;
1658 cds_lfht_lookup(state
->sessions_ht
,
1659 hash_key_str(name
, lttng_ht_seed
),
1663 node
= cds_lfht_iter_get_node(&iter
);
1665 DBG("Found session info of session \"%s\" (uid = %i, gid = %i)",
1667 session
= caa_container_of(node
, struct session_info
,
1669 LTTNG_ASSERT(session
->uid
== uid
);
1670 LTTNG_ASSERT(session
->gid
== gid
);
1671 session_info_get(session
);
1675 trigger_list
= lttng_session_trigger_list_build(state
, name
);
1676 if (!trigger_list
) {
1680 session
= session_info_create(name
, uid
, gid
, trigger_list
,
1681 state
->sessions_ht
);
1683 ERR("Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
1685 lttng_session_trigger_list_destroy(trigger_list
);
1688 trigger_list
= NULL
;
1690 cds_lfht_add(state
->sessions_ht
, hash_key_str(name
, lttng_ht_seed
),
1691 &session
->sessions_ht_node
);
1697 session_info_put(session
);
1702 int handle_notification_thread_command_add_channel(
1703 struct notification_thread_state
*state
,
1704 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1705 const char *channel_name
, enum lttng_domain_type channel_domain
,
1706 uint64_t channel_key_int
, uint64_t channel_capacity
,
1707 enum lttng_error_code
*cmd_result
)
1709 struct cds_list_head trigger_list
;
1710 struct channel_info
*new_channel_info
= NULL
;
1711 struct channel_key channel_key
= {
1712 .key
= channel_key_int
,
1713 .domain
= channel_domain
,
1715 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
1716 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1717 int trigger_count
= 0;
1718 struct cds_lfht_iter iter
;
1719 struct session_info
*session_info
= NULL
;
1721 DBG("Adding channel %s from session %s, channel key = %" PRIu64
" in %s domain",
1722 channel_name
, session_name
, channel_key_int
,
1723 lttng_domain_type_str(channel_domain
));
1725 CDS_INIT_LIST_HEAD(&trigger_list
);
1727 session_info
= find_or_create_session_info(state
, session_name
,
1728 session_uid
, session_gid
);
1729 if (!session_info
) {
1730 /* Allocation error or an internal error occurred. */
1734 new_channel_info
= channel_info_create(channel_name
, &channel_key
,
1735 channel_capacity
, session_info
);
1736 if (!new_channel_info
) {
1741 /* Build a list of all triggers applying to the new channel. */
1742 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1744 struct lttng_trigger_list_element
*new_element
;
1746 if (!trigger_applies_to_channel(trigger_ht_element
->trigger
,
1747 new_channel_info
)) {
1751 new_element
= (lttng_trigger_list_element
*) zmalloc(sizeof(*new_element
));
1756 CDS_INIT_LIST_HEAD(&new_element
->node
);
1757 new_element
->trigger
= trigger_ht_element
->trigger
;
1758 cds_list_add(&new_element
->node
, &trigger_list
);
1763 DBG("Found %i triggers that apply to newly added channel",
1765 channel_trigger_list
= (lttng_channel_trigger_list
*) zmalloc(sizeof(*channel_trigger_list
));
1766 if (!channel_trigger_list
) {
1769 channel_trigger_list
->channel_key
= new_channel_info
->key
;
1770 CDS_INIT_LIST_HEAD(&channel_trigger_list
->list
);
1771 cds_lfht_node_init(&channel_trigger_list
->channel_triggers_ht_node
);
1772 cds_list_splice(&trigger_list
, &channel_trigger_list
->list
);
1775 /* Add channel to the channel_ht which owns the channel_infos. */
1776 cds_lfht_add(state
->channels_ht
,
1777 hash_channel_key(&new_channel_info
->key
),
1778 &new_channel_info
->channels_ht_node
);
1780 * Add the list of triggers associated with this channel to the
1781 * channel_triggers_ht.
1783 cds_lfht_add(state
->channel_triggers_ht
,
1784 hash_channel_key(&new_channel_info
->key
),
1785 &channel_trigger_list
->channel_triggers_ht_node
);
1787 session_info_put(session_info
);
1788 *cmd_result
= LTTNG_OK
;
1791 channel_info_destroy(new_channel_info
);
1792 session_info_put(session_info
);
1797 void free_channel_trigger_list_rcu(struct rcu_head
*node
)
1799 free(caa_container_of(node
, struct lttng_channel_trigger_list
,
1804 void free_channel_state_sample_rcu(struct rcu_head
*node
)
1806 free(caa_container_of(node
, struct channel_state_sample
,
1811 int handle_notification_thread_command_remove_channel(
1812 struct notification_thread_state
*state
,
1813 uint64_t channel_key
, enum lttng_domain_type domain
,
1814 enum lttng_error_code
*cmd_result
)
1816 struct cds_lfht_node
*node
;
1817 struct cds_lfht_iter iter
;
1818 struct lttng_channel_trigger_list
*trigger_list
;
1819 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1820 struct channel_key key
= { .key
= channel_key
, .domain
= domain
};
1821 struct channel_info
*channel_info
;
1823 DBG("Removing channel key = %" PRIu64
" in %s domain",
1824 channel_key
, lttng_domain_type_str(domain
));
1828 cds_lfht_lookup(state
->channel_triggers_ht
,
1829 hash_channel_key(&key
),
1830 match_channel_trigger_list
,
1833 node
= cds_lfht_iter_get_node(&iter
);
1835 * There is a severe internal error if we are being asked to remove a
1836 * channel that doesn't exist.
1839 ERR("Channel being removed is unknown to the notification thread");
1843 /* Free the list of triggers associated with this channel. */
1844 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
1845 channel_triggers_ht_node
);
1846 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1847 &trigger_list
->list
, node
) {
1848 cds_list_del(&trigger_list_element
->node
);
1849 free(trigger_list_element
);
1851 cds_lfht_del(state
->channel_triggers_ht
, node
);
1852 call_rcu(&trigger_list
->rcu_node
, free_channel_trigger_list_rcu
);
1854 /* Free sampled channel state. */
1855 cds_lfht_lookup(state
->channel_state_ht
,
1856 hash_channel_key(&key
),
1857 match_channel_state_sample
,
1860 node
= cds_lfht_iter_get_node(&iter
);
1862 * This is expected to be NULL if the channel is destroyed before we
1863 * received a sample.
1866 struct channel_state_sample
*sample
= caa_container_of(node
,
1867 struct channel_state_sample
,
1868 channel_state_ht_node
);
1870 cds_lfht_del(state
->channel_state_ht
, node
);
1871 call_rcu(&sample
->rcu_node
, free_channel_state_sample_rcu
);
1874 /* Remove the channel from the channels_ht and free it. */
1875 cds_lfht_lookup(state
->channels_ht
,
1876 hash_channel_key(&key
),
1880 node
= cds_lfht_iter_get_node(&iter
);
1882 channel_info
= caa_container_of(node
, struct channel_info
,
1884 cds_lfht_del(state
->channels_ht
, node
);
1885 channel_info_destroy(channel_info
);
1888 *cmd_result
= LTTNG_OK
;
1893 int handle_notification_thread_command_session_rotation(
1894 struct notification_thread_state
*state
,
1895 enum notification_thread_command_type cmd_type
,
1896 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1897 uint64_t trace_archive_chunk_id
,
1898 struct lttng_trace_archive_location
*location
,
1899 enum lttng_error_code
*_cmd_result
)
1902 enum lttng_error_code cmd_result
= LTTNG_OK
;
1903 struct lttng_session_trigger_list
*trigger_list
;
1904 struct lttng_trigger_list_element
*trigger_list_element
;
1905 struct session_info
*session_info
;
1906 const struct lttng_credentials session_creds
= {
1907 .uid
= LTTNG_OPTIONAL_INIT_VALUE(session_uid
),
1908 .gid
= LTTNG_OPTIONAL_INIT_VALUE(session_gid
),
1913 session_info
= find_or_create_session_info(state
, session_name
,
1914 session_uid
, session_gid
);
1915 if (!session_info
) {
1916 /* Allocation error or an internal error occurred. */
1918 cmd_result
= LTTNG_ERR_NOMEM
;
1922 session_info
->rotation
.ongoing
=
1923 cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
;
1924 session_info
->rotation
.id
= trace_archive_chunk_id
;
1925 trigger_list
= get_session_trigger_list(state
, session_name
);
1926 if (!trigger_list
) {
1927 DBG("No triggers applying to session \"%s\" found",
1932 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
1934 const struct lttng_condition
*condition
;
1935 struct lttng_trigger
*trigger
;
1936 struct notification_client_list
*client_list
;
1937 struct lttng_evaluation
*evaluation
= NULL
;
1938 enum lttng_condition_type condition_type
;
1939 enum action_executor_status executor_status
;
1941 trigger
= trigger_list_element
->trigger
;
1942 condition
= lttng_trigger_get_const_condition(trigger
);
1943 LTTNG_ASSERT(condition
);
1944 condition_type
= lttng_condition_get_type(condition
);
1946 if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
&&
1947 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1949 } else if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
&&
1950 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
) {
1954 client_list
= get_client_list_from_condition(state
, condition
);
1955 if (cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1956 evaluation
= lttng_evaluation_session_rotation_ongoing_create(
1957 trace_archive_chunk_id
);
1959 evaluation
= lttng_evaluation_session_rotation_completed_create(
1960 trace_archive_chunk_id
, location
);
1964 /* Internal error */
1966 cmd_result
= LTTNG_ERR_UNK
;
1971 * Ownership of `evaluation` transferred to the action executor
1972 * no matter the result.
1974 executor_status
= action_executor_enqueue_trigger(
1975 state
->executor
, trigger
, evaluation
,
1976 &session_creds
, client_list
);
1978 switch (executor_status
) {
1979 case ACTION_EXECUTOR_STATUS_OK
:
1981 case ACTION_EXECUTOR_STATUS_ERROR
:
1982 case ACTION_EXECUTOR_STATUS_INVALID
:
1984 * TODO Add trigger identification (name/id) when
1985 * it is added to the API.
1987 ERR("Fatal error occurred while enqueuing action associated with session rotation trigger");
1990 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
1992 * TODO Add trigger identification (name/id) when
1993 * it is added to the API.
1995 * Not a fatal error.
1997 WARN("No space left when enqueuing action associated with session rotation trigger");
2005 notification_client_list_put(client_list
);
2006 if (caa_unlikely(ret
)) {
2011 session_info_put(session_info
);
2012 *_cmd_result
= cmd_result
;
2018 int handle_notification_thread_command_add_tracer_event_source(
2019 struct notification_thread_state
*state
,
2020 int tracer_event_source_fd
,
2021 enum lttng_domain_type domain_type
,
2022 enum lttng_error_code
*_cmd_result
)
2025 enum lttng_error_code cmd_result
= LTTNG_OK
;
2026 struct notification_event_tracer_event_source_element
*element
= NULL
;
2028 element
= (notification_event_tracer_event_source_element
*) zmalloc(sizeof(*element
));
2030 cmd_result
= LTTNG_ERR_NOMEM
;
2035 element
->fd
= tracer_event_source_fd
;
2036 element
->domain
= domain_type
;
2038 cds_list_add(&element
->node
, &state
->tracer_event_sources_list
);
2040 DBG3("Adding tracer event source fd to poll set: tracer_event_source_fd = %d, domain = '%s'",
2041 tracer_event_source_fd
,
2042 lttng_domain_type_str(domain_type
));
2044 /* Adding the read side pipe to the event poll. */
2045 ret
= lttng_poll_add(&state
->events
, tracer_event_source_fd
, LPOLLIN
| LPOLLERR
);
2047 ERR("Failed to add tracer event source to poll set: tracer_event_source_fd = %d, domain = '%s'",
2048 tracer_event_source_fd
,
2049 lttng_domain_type_str(element
->domain
));
2050 cds_list_del(&element
->node
);
2055 element
->is_fd_in_poll_set
= true;
2058 *_cmd_result
= cmd_result
;
2063 int drain_event_notifier_notification_pipe(
2064 struct notification_thread_state
*state
,
2065 int pipe
, enum lttng_domain_type domain
)
2067 struct lttng_poll_event events
= {0};
2070 ret
= lttng_poll_create(&events
, 1, LTTNG_CLOEXEC
);
2072 ERR("Error creating lttng_poll_event");
2076 ret
= lttng_poll_add(&events
, pipe
, LPOLLIN
);
2078 ERR("Error adding fd event notifier notification pipe to lttng_poll_event: fd = %d",
2085 * Continue to consume notifications as long as there are new
2086 * ones coming in. The tracer has been asked to stop producing
2089 * LPOLLIN is explicitly checked since LPOLLHUP is implicitly
2090 * monitored (on Linux, at least) and will be returned when
2091 * the pipe is closed but empty.
2093 ret
= lttng_poll_wait_interruptible(&events
, 0);
2094 if (ret
== 0 || (LTTNG_POLL_GETEV(&events
, 0) & LPOLLIN
) == 0) {
2095 /* No more notification to be read on this pipe. */
2098 } else if (ret
< 0) {
2099 PERROR("Failed on lttng_poll_wait_interruptible() call");
2104 ret
= handle_one_event_notifier_notification(state
, pipe
, domain
);
2106 ERR("Error consuming an event notifier notification from pipe: fd = %d",
2111 lttng_poll_clean(&events
);
2116 struct notification_event_tracer_event_source_element
*
2117 find_tracer_event_source_element(struct notification_thread_state
*state
,
2118 int tracer_event_source_fd
)
2120 struct notification_event_tracer_event_source_element
*source_element
;
2122 cds_list_for_each_entry(source_element
,
2123 &state
->tracer_event_sources_list
, node
) {
2124 if (source_element
->fd
== tracer_event_source_fd
) {
2129 source_element
= NULL
;
2131 return source_element
;
2135 int remove_tracer_event_source_from_pollset(
2136 struct notification_thread_state
*state
,
2137 struct notification_event_tracer_event_source_element
*source_element
)
2141 LTTNG_ASSERT(source_element
->is_fd_in_poll_set
);
2143 DBG3("Removing tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2145 lttng_domain_type_str(source_element
->domain
));
2147 /* Removing the fd from the event poll set. */
2148 ret
= lttng_poll_del(&state
->events
, source_element
->fd
);
2150 ERR("Failed to remove tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2152 lttng_domain_type_str(source_element
->domain
));
2157 source_element
->is_fd_in_poll_set
= false;
2160 * Force the notification thread to restart the poll() loop to ensure
2161 * that any events from the removed fd are removed.
2163 state
->restart_poll
= true;
2165 ret
= drain_event_notifier_notification_pipe(state
, source_element
->fd
,
2166 source_element
->domain
);
2168 ERR("Error draining event notifier notification: tracer_event_source_fd = %d, domain = %s",
2170 lttng_domain_type_str(source_element
->domain
));
2179 int handle_notification_thread_tracer_event_source_died(
2180 struct notification_thread_state
*state
,
2181 int tracer_event_source_fd
)
2184 struct notification_event_tracer_event_source_element
*source_element
;
2186 source_element
= find_tracer_event_source_element(state
,
2187 tracer_event_source_fd
);
2189 LTTNG_ASSERT(source_element
);
2191 ret
= remove_tracer_event_source_from_pollset(state
, source_element
);
2193 ERR("Failed to remove dead tracer event source from poll set");
2200 int handle_notification_thread_command_remove_tracer_event_source(
2201 struct notification_thread_state
*state
,
2202 int tracer_event_source_fd
,
2203 enum lttng_error_code
*_cmd_result
)
2206 enum lttng_error_code cmd_result
= LTTNG_OK
;
2207 struct notification_event_tracer_event_source_element
*source_element
= NULL
;
2209 source_element
= find_tracer_event_source_element(state
,
2210 tracer_event_source_fd
);
2212 LTTNG_ASSERT(source_element
);
2214 /* Remove the tracer source from the list. */
2215 cds_list_del(&source_element
->node
);
2217 if (!source_element
->is_fd_in_poll_set
) {
2218 /* Skip the poll set removal. */
2222 ret
= remove_tracer_event_source_from_pollset(state
, source_element
);
2224 ERR("Failed to remove tracer event source from poll set");
2225 cmd_result
= LTTNG_ERR_FATAL
;
2229 free(source_element
);
2230 *_cmd_result
= cmd_result
;
2234 static int handle_notification_thread_command_list_triggers(
2235 struct notification_thread_handle
*handle
__attribute__((unused
)),
2236 struct notification_thread_state
*state
,
2238 struct lttng_triggers
**triggers
,
2239 enum lttng_error_code
*_cmd_result
)
2242 enum lttng_error_code cmd_result
= LTTNG_OK
;
2243 struct cds_lfht_iter iter
;
2244 struct lttng_trigger_ht_element
*trigger_ht_element
;
2245 struct lttng_triggers
*local_triggers
= NULL
;
2246 const struct lttng_credentials
*creds
;
2250 local_triggers
= lttng_triggers_create();
2251 if (!local_triggers
) {
2252 /* Not a fatal error. */
2253 cmd_result
= LTTNG_ERR_NOMEM
;
2257 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
,
2258 trigger_ht_element
, node
) {
2260 * Only return the triggers to which the client has access.
2261 * The root user has visibility over all triggers.
2263 creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
2264 if (client_uid
!= lttng_credentials_get_uid(creds
) && client_uid
!= 0) {
2268 ret
= lttng_triggers_add(local_triggers
,
2269 trigger_ht_element
->trigger
);
2271 /* Not a fatal error. */
2273 cmd_result
= LTTNG_ERR_NOMEM
;
2278 /* Transferring ownership to the caller. */
2279 *triggers
= local_triggers
;
2280 local_triggers
= NULL
;
2284 lttng_triggers_destroy(local_triggers
);
2285 *_cmd_result
= cmd_result
;
2289 static inline void get_trigger_info_for_log(const struct lttng_trigger
*trigger
,
2290 const char **trigger_name
,
2291 uid_t
*trigger_owner_uid
)
2293 enum lttng_trigger_status trigger_status
;
2295 trigger_status
= lttng_trigger_get_name(trigger
, trigger_name
);
2296 switch (trigger_status
) {
2297 case LTTNG_TRIGGER_STATUS_OK
:
2299 case LTTNG_TRIGGER_STATUS_UNSET
:
2300 *trigger_name
= "(anonymous)";
2306 trigger_status
= lttng_trigger_get_owner_uid(trigger
,
2308 LTTNG_ASSERT(trigger_status
== LTTNG_TRIGGER_STATUS_OK
);
2311 static int handle_notification_thread_command_get_trigger(
2312 struct notification_thread_state
*state
,
2313 const struct lttng_trigger
*trigger
,
2314 struct lttng_trigger
**registered_trigger
,
2315 enum lttng_error_code
*_cmd_result
)
2318 struct cds_lfht_iter iter
;
2319 struct lttng_trigger_ht_element
*trigger_ht_element
;
2320 enum lttng_error_code cmd_result
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
2321 const char *trigger_name
;
2322 uid_t trigger_owner_uid
;
2326 cds_lfht_for_each_entry(
2327 state
->triggers_ht
, &iter
, trigger_ht_element
, node
) {
2328 if (lttng_trigger_is_equal(
2329 trigger
, trigger_ht_element
->trigger
)) {
2330 /* Take one reference on the return trigger. */
2331 *registered_trigger
= trigger_ht_element
->trigger
;
2332 lttng_trigger_get(*registered_trigger
);
2334 cmd_result
= LTTNG_OK
;
2339 /* Not a fatal error if the trigger is not found. */
2340 get_trigger_info_for_log(trigger
, &trigger_name
, &trigger_owner_uid
);
2341 DBG("Failed to retrieve registered version of trigger: trigger name = '%s', trigger owner uid = %d",
2342 trigger_name
, (int) trigger_owner_uid
);
2348 *_cmd_result
= cmd_result
;
2353 bool condition_is_supported(struct lttng_condition
*condition
)
2357 switch (lttng_condition_get_type(condition
)) {
2358 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
2359 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
2362 enum lttng_domain_type domain
;
2364 ret
= lttng_condition_buffer_usage_get_domain_type(condition
,
2366 LTTNG_ASSERT(ret
== 0);
2368 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2369 is_supported
= true;
2374 * Older kernel tracers don't expose the API to monitor their
2375 * buffers. Therefore, we reject triggers that require that
2376 * mechanism to be available to be evaluated.
2378 * Assume unsupported on error.
2380 is_supported
= kernel_supports_ring_buffer_snapshot_sample_positions() == 1;
2383 case LTTNG_CONDITION_TYPE_EVENT_RULE_MATCHES
:
2385 const struct lttng_event_rule
*event_rule
;
2386 enum lttng_domain_type domain
;
2387 const enum lttng_condition_status status
=
2388 lttng_condition_event_rule_matches_get_rule(
2389 condition
, &event_rule
);
2391 LTTNG_ASSERT(status
== LTTNG_CONDITION_STATUS_OK
);
2393 domain
= lttng_event_rule_get_domain_type(event_rule
);
2394 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2395 is_supported
= true;
2400 * Older kernel tracers can't emit notification. Therefore, we
2401 * reject triggers that require that mechanism to be available
2404 * Assume unsupported on error.
2406 is_supported
= kernel_supports_event_notifiers() == 1;
2410 is_supported
= true;
2413 return is_supported
;
2416 /* Must be called with RCU read lock held. */
2418 int bind_trigger_to_matching_session(struct lttng_trigger
*trigger
,
2419 struct notification_thread_state
*state
)
2422 const struct lttng_condition
*condition
;
2423 const char *session_name
;
2424 struct lttng_session_trigger_list
*trigger_list
;
2426 ASSERT_RCU_READ_LOCKED();
2428 condition
= lttng_trigger_get_const_condition(trigger
);
2429 switch (lttng_condition_get_type(condition
)) {
2430 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
2431 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
2433 enum lttng_condition_status status
;
2435 status
= lttng_condition_session_rotation_get_session_name(
2436 condition
, &session_name
);
2437 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
2438 ERR("Failed to bind trigger to session: unable to get 'session_rotation' condition's session name");
2449 trigger_list
= get_session_trigger_list(state
, session_name
);
2450 if (!trigger_list
) {
2451 DBG("Unable to bind trigger applying to session \"%s\" as it is not yet known to the notification system",
2457 DBG("Newly registered trigger bound to session \"%s\"",
2459 ret
= lttng_session_trigger_list_add(trigger_list
, trigger
);
2464 /* Must be called with RCU read lock held. */
2466 int bind_trigger_to_matching_channels(struct lttng_trigger
*trigger
,
2467 struct notification_thread_state
*state
)
2470 struct cds_lfht_node
*node
;
2471 struct cds_lfht_iter iter
;
2472 struct channel_info
*channel
;
2474 ASSERT_RCU_READ_LOCKED();
2476 cds_lfht_for_each_entry(state
->channels_ht
, &iter
, channel
,
2478 struct lttng_trigger_list_element
*trigger_list_element
;
2479 struct lttng_channel_trigger_list
*trigger_list
;
2480 struct cds_lfht_iter lookup_iter
;
2482 if (!trigger_applies_to_channel(trigger
, channel
)) {
2486 cds_lfht_lookup(state
->channel_triggers_ht
,
2487 hash_channel_key(&channel
->key
),
2488 match_channel_trigger_list
,
2491 node
= cds_lfht_iter_get_node(&lookup_iter
);
2493 trigger_list
= caa_container_of(node
,
2494 struct lttng_channel_trigger_list
,
2495 channel_triggers_ht_node
);
2497 trigger_list_element
= (lttng_trigger_list_element
*) zmalloc(sizeof(*trigger_list_element
));
2498 if (!trigger_list_element
) {
2502 CDS_INIT_LIST_HEAD(&trigger_list_element
->node
);
2503 trigger_list_element
->trigger
= trigger
;
2504 cds_list_add(&trigger_list_element
->node
, &trigger_list
->list
);
2505 DBG("Newly registered trigger bound to channel \"%s\"",
2513 bool is_trigger_action_notify(const struct lttng_trigger
*trigger
)
2515 bool is_notify
= false;
2516 unsigned int i
, count
;
2517 enum lttng_action_status action_status
;
2518 const struct lttng_action
*action
=
2519 lttng_trigger_get_const_action(trigger
);
2520 enum lttng_action_type action_type
;
2522 LTTNG_ASSERT(action
);
2523 action_type
= lttng_action_get_type(action
);
2524 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2527 } else if (action_type
!= LTTNG_ACTION_TYPE_LIST
) {
2531 action_status
= lttng_action_list_get_count(action
, &count
);
2532 LTTNG_ASSERT(action_status
== LTTNG_ACTION_STATUS_OK
);
2534 for (i
= 0; i
< count
; i
++) {
2535 const struct lttng_action
*inner_action
=
2536 lttng_action_list_get_at_index(
2539 action_type
= lttng_action_get_type(inner_action
);
2540 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2550 static bool trigger_name_taken(struct notification_thread_state
*state
,
2551 const struct lttng_trigger
*trigger
)
2553 struct cds_lfht_iter iter
;
2556 * No duplicata is allowed in the triggers_by_name_uid_ht.
2557 * The match is done against the trigger name and uid.
2559 cds_lfht_lookup(state
->triggers_by_name_uid_ht
,
2560 hash_trigger_by_name_uid(trigger
),
2561 match_trigger_by_name_uid
,
2564 return !!cds_lfht_iter_get_node(&iter
);
2568 enum lttng_error_code
generate_trigger_name(
2569 struct notification_thread_state
*state
,
2570 struct lttng_trigger
*trigger
, const char **name
)
2572 enum lttng_error_code ret_code
= LTTNG_OK
;
2574 enum lttng_trigger_status status
;
2577 const int ret
= lttng_trigger_generate_name(trigger
,
2578 state
->trigger_id
.name_offset
++);
2580 /* The only reason this can fail right now. */
2581 ret_code
= LTTNG_ERR_NOMEM
;
2585 status
= lttng_trigger_get_name(trigger
, name
);
2586 LTTNG_ASSERT(status
== LTTNG_TRIGGER_STATUS_OK
);
2588 taken
= trigger_name_taken(state
, trigger
);
2589 } while (taken
|| state
->trigger_id
.name_offset
== UINT64_MAX
);
2595 void notif_thread_state_remove_trigger_ht_elem(
2596 struct notification_thread_state
*state
,
2597 struct lttng_trigger_ht_element
*trigger_ht_element
)
2599 LTTNG_ASSERT(state
);
2600 LTTNG_ASSERT(trigger_ht_element
);
2602 cds_lfht_del(state
->triggers_ht
, &trigger_ht_element
->node
);
2603 cds_lfht_del(state
->triggers_by_name_uid_ht
, &trigger_ht_element
->node_by_name_uid
);
2607 enum lttng_error_code
setup_tracer_notifier(
2608 struct notification_thread_state
*state
,
2609 struct lttng_trigger
*trigger
)
2611 enum lttng_error_code ret
;
2612 enum event_notifier_error_accounting_status error_accounting_status
;
2613 struct cds_lfht_node
*node
;
2614 uint64_t error_counter_index
= 0;
2615 struct lttng_condition
*condition
= lttng_trigger_get_condition(trigger
);
2616 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
= NULL
;
2618 trigger_tokens_ht_element
= (notification_trigger_tokens_ht_element
*) zmalloc(sizeof(*trigger_tokens_ht_element
));
2619 if (!trigger_tokens_ht_element
) {
2620 ret
= LTTNG_ERR_NOMEM
;
2624 /* Add trigger token to the trigger_tokens_ht. */
2625 cds_lfht_node_init(&trigger_tokens_ht_element
->node
);
2626 trigger_tokens_ht_element
->token
= LTTNG_OPTIONAL_GET(trigger
->tracer_token
);
2627 trigger_tokens_ht_element
->trigger
= trigger
;
2629 node
= cds_lfht_add_unique(state
->trigger_tokens_ht
,
2630 hash_key_u64(&trigger_tokens_ht_element
->token
, lttng_ht_seed
),
2631 match_trigger_token
,
2632 &trigger_tokens_ht_element
->token
,
2633 &trigger_tokens_ht_element
->node
);
2634 if (node
!= &trigger_tokens_ht_element
->node
) {
2635 ret
= LTTNG_ERR_TRIGGER_EXISTS
;
2636 goto error_free_ht_element
;
2639 error_accounting_status
= event_notifier_error_accounting_register_event_notifier(
2640 trigger
, &error_counter_index
);
2641 if (error_accounting_status
!= EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK
) {
2642 if (error_accounting_status
== EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_NO_INDEX_AVAILABLE
) {
2643 DBG("Trigger list error accounting counter full.");
2644 ret
= LTTNG_ERR_EVENT_NOTIFIER_ERROR_ACCOUNTING_FULL
;
2646 ERR("Error registering trigger for error accounting");
2647 ret
= LTTNG_ERR_EVENT_NOTIFIER_REGISTRATION
;
2650 goto error_remove_ht_element
;
2653 lttng_condition_event_rule_matches_set_error_counter_index(
2654 condition
, error_counter_index
);
2659 error_remove_ht_element
:
2660 cds_lfht_del(state
->trigger_tokens_ht
, &trigger_tokens_ht_element
->node
);
2661 error_free_ht_element
:
2662 free(trigger_tokens_ht_element
);
2668 * FIXME A client's credentials are not checked when registering a trigger.
2670 * The effects of this are benign since:
2671 * - The client will succeed in registering the trigger, as it is valid,
2672 * - The trigger will, internally, be bound to the channel/session,
2673 * - The notifications will not be sent since the client's credentials
2674 * are checked against the channel at that moment.
2676 * If this function returns a non-zero value, it means something is
2677 * fundamentally broken and the whole subsystem/thread will be torn down.
2679 * If a non-fatal error occurs, just set the cmd_result to the appropriate
2683 int handle_notification_thread_command_register_trigger(
2684 struct notification_thread_state
*state
,
2685 struct lttng_trigger
*trigger
,
2686 bool is_trigger_anonymous
,
2687 enum lttng_error_code
*cmd_result
)
2690 struct lttng_condition
*condition
;
2691 struct notification_client_list
*client_list
= NULL
;
2692 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2693 struct cds_lfht_node
*node
;
2694 const char* trigger_name
;
2695 bool free_trigger
= true;
2696 struct lttng_evaluation
*evaluation
= NULL
;
2697 struct lttng_credentials object_creds
;
2700 enum action_executor_status executor_status
;
2701 const uint64_t trigger_tracer_token
=
2702 state
->trigger_id
.next_tracer_token
++;
2706 /* Set the trigger's tracer token. */
2707 lttng_trigger_set_tracer_token(trigger
, trigger_tracer_token
);
2709 if (!is_trigger_anonymous
) {
2710 if (lttng_trigger_get_name(trigger
, &trigger_name
) ==
2711 LTTNG_TRIGGER_STATUS_UNSET
) {
2712 const enum lttng_error_code ret_code
=
2713 generate_trigger_name(state
, trigger
,
2716 if (ret_code
!= LTTNG_OK
) {
2719 *cmd_result
= ret_code
;
2722 } else if (trigger_name_taken(state
, trigger
)) {
2723 /* Not a fatal error. */
2724 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2729 trigger_name
= "(anonymous)";
2732 condition
= lttng_trigger_get_condition(trigger
);
2733 LTTNG_ASSERT(condition
);
2735 /* Some conditions require tracers to implement a minimal ABI version. */
2736 if (!condition_is_supported(condition
)) {
2737 *cmd_result
= LTTNG_ERR_NOT_SUPPORTED
;
2741 trigger_ht_element
= (lttng_trigger_ht_element
*) zmalloc(sizeof(*trigger_ht_element
));
2742 if (!trigger_ht_element
) {
2747 /* Add trigger to the trigger_ht. */
2748 cds_lfht_node_init(&trigger_ht_element
->node
);
2749 cds_lfht_node_init(&trigger_ht_element
->node_by_name_uid
);
2750 trigger_ht_element
->trigger
= trigger
;
2752 node
= cds_lfht_add_unique(state
->triggers_ht
,
2753 lttng_condition_hash(condition
),
2756 &trigger_ht_element
->node
);
2757 if (node
!= &trigger_ht_element
->node
) {
2758 /* Not a fatal error, simply report it to the client. */
2759 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2760 goto error_free_ht_element
;
2763 node
= cds_lfht_add_unique(state
->triggers_by_name_uid_ht
,
2764 hash_trigger_by_name_uid(trigger
),
2765 match_trigger_by_name_uid
,
2767 &trigger_ht_element
->node_by_name_uid
);
2768 if (node
!= &trigger_ht_element
->node_by_name_uid
) {
2769 /* Internal error: add to triggers_ht should have failed. */
2771 goto error_free_ht_element
;
2774 /* From this point consider the trigger registered. */
2775 lttng_trigger_set_as_registered(trigger
);
2778 * Some triggers might need a tracer notifier depending on its
2779 * condition and actions.
2781 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
2782 enum lttng_error_code error_code
;
2784 error_code
= setup_tracer_notifier(state
, trigger
);
2785 if (error_code
!= LTTNG_OK
) {
2786 notif_thread_state_remove_trigger_ht_elem(state
,
2787 trigger_ht_element
);
2788 if (error_code
== LTTNG_ERR_NOMEM
) {
2791 *cmd_result
= error_code
;
2795 goto error_free_ht_element
;
2800 * The rest only applies to triggers that have a "notify" action.
2801 * It is not skipped as this is the only action type currently
2804 if (is_trigger_action_notify(trigger
)) {
2806 * Find or create the client list of this condition. It may
2807 * already be present if another trigger is already registered
2808 * with the same condition.
2810 client_list
= get_client_list_from_condition(state
, condition
);
2813 * No client list for this condition yet. We create new
2814 * one and build it up.
2816 client_list
= notification_client_list_create(state
, condition
);
2818 ERR("Error creating notification client list for trigger %s", trigger
->name
);
2819 goto error_free_ht_element
;
2823 CDS_INIT_LIST_HEAD(&trigger_ht_element
->client_list_trigger_node
);
2825 pthread_mutex_lock(&client_list
->lock
);
2826 cds_list_add(&trigger_ht_element
->client_list_trigger_node
, &client_list
->triggers_list
);
2827 pthread_mutex_unlock(&client_list
->lock
);
2831 * Ownership of the trigger and of its wrapper was transfered to
2832 * the triggers_ht. Same for token ht element if necessary.
2834 trigger_ht_element
= NULL
;
2835 free_trigger
= false;
2837 switch (get_condition_binding_object(condition
)) {
2838 case LTTNG_OBJECT_TYPE_SESSION
:
2839 /* Add the trigger to the list if it matches a known session. */
2840 ret
= bind_trigger_to_matching_session(trigger
, state
);
2842 goto error_free_ht_element
;
2845 case LTTNG_OBJECT_TYPE_CHANNEL
:
2847 * Add the trigger to list of triggers bound to the channels
2850 ret
= bind_trigger_to_matching_channels(trigger
, state
);
2852 goto error_free_ht_element
;
2855 case LTTNG_OBJECT_TYPE_NONE
:
2858 ERR("Unknown object type on which to bind a newly registered trigger was encountered");
2860 goto error_free_ht_element
;
2864 * The new trigger's condition must be evaluated against the current
2867 * In the case of `notify` action, nothing preventing clients from
2868 * subscribing to a condition before the corresponding trigger is
2869 * registered, we have to evaluate this new condition right away.
2871 * At some point, we were waiting for the next "evaluation" (e.g. on
2872 * reception of a channel sample) to evaluate this new condition, but
2875 * The reason it was broken is that waiting for the next sample
2876 * does not allow us to properly handle transitions for edge-triggered
2879 * Consider this example: when we handle a new channel sample, we
2880 * evaluate each conditions twice: once with the previous state, and
2881 * again with the newest state. We then use those two results to
2882 * determine whether a state change happened: a condition was false and
2883 * became true. If a state change happened, we have to notify clients.
2885 * Now, if a client subscribes to a given notification and registers
2886 * a trigger *after* that subscription, we have to make sure the
2887 * condition is evaluated at this point while considering only the
2888 * current state. Otherwise, the next evaluation cycle may only see
2889 * that the evaluations remain the same (true for samples n-1 and n) and
2890 * the client will never know that the condition has been met.
2892 switch (get_condition_binding_object(condition
)) {
2893 case LTTNG_OBJECT_TYPE_SESSION
:
2894 ret
= evaluate_session_condition_for_client(condition
, state
,
2895 &evaluation
, &object_uid
,
2897 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2898 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2900 case LTTNG_OBJECT_TYPE_CHANNEL
:
2901 ret
= evaluate_channel_condition_for_client(condition
, state
,
2902 &evaluation
, &object_uid
,
2904 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2905 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2907 case LTTNG_OBJECT_TYPE_NONE
:
2910 case LTTNG_OBJECT_TYPE_UNKNOWN
:
2918 goto error_free_ht_element
;
2921 DBG("Newly registered trigger's condition evaluated to %s",
2922 evaluation
? "true" : "false");
2924 /* Evaluation yielded nothing. Normal exit. */
2930 * Ownership of `evaluation` transferred to the action executor
2931 * no matter the result.
2933 executor_status
= action_executor_enqueue_trigger(state
->executor
,
2934 trigger
, evaluation
, &object_creds
, client_list
);
2936 switch (executor_status
) {
2937 case ACTION_EXECUTOR_STATUS_OK
:
2939 case ACTION_EXECUTOR_STATUS_ERROR
:
2940 case ACTION_EXECUTOR_STATUS_INVALID
:
2942 * TODO Add trigger identification (name/id) when
2943 * it is added to the API.
2945 ERR("Fatal error occurred while enqueuing action associated to newly registered trigger");
2947 goto error_free_ht_element
;
2948 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
2950 * TODO Add trigger identification (name/id) when
2951 * it is added to the API.
2953 * Not a fatal error.
2955 WARN("No space left when enqueuing action associated to newly registered trigger");
2963 *cmd_result
= LTTNG_OK
;
2964 DBG("Registered trigger: name = `%s`, tracer token = %" PRIu64
,
2965 trigger_name
, trigger_tracer_token
);
2968 error_free_ht_element
:
2969 if (trigger_ht_element
) {
2970 /* Delayed removal due to RCU constraint on delete. */
2971 call_rcu(&trigger_ht_element
->rcu_node
,
2972 free_lttng_trigger_ht_element_rcu
);
2977 * Other objects might have a reference to the trigger, mark it
2980 lttng_trigger_set_as_unregistered(trigger
);
2981 lttng_trigger_destroy(trigger
);
2989 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
)
2991 free(caa_container_of(node
, struct lttng_trigger_ht_element
,
2996 void free_notification_trigger_tokens_ht_element_rcu(struct rcu_head
*node
)
2998 free(caa_container_of(node
, struct notification_trigger_tokens_ht_element
,
3003 void teardown_tracer_notifier(struct notification_thread_state
*state
,
3004 const struct lttng_trigger
*trigger
)
3006 struct cds_lfht_iter iter
;
3007 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
;
3009 cds_lfht_for_each_entry(state
->trigger_tokens_ht
, &iter
,
3010 trigger_tokens_ht_element
, node
) {
3012 if (!lttng_trigger_is_equal(trigger
,
3013 trigger_tokens_ht_element
->trigger
)) {
3017 event_notifier_error_accounting_unregister_event_notifier(
3018 trigger_tokens_ht_element
->trigger
);
3020 /* TODO talk to all app and remove it */
3021 DBG("Removed trigger from tokens_ht");
3022 cds_lfht_del(state
->trigger_tokens_ht
,
3023 &trigger_tokens_ht_element
->node
);
3025 call_rcu(&trigger_tokens_ht_element
->rcu_node
,
3026 free_notification_trigger_tokens_ht_element_rcu
);
3033 int handle_notification_thread_command_unregister_trigger(
3034 struct notification_thread_state
*state
,
3035 const struct lttng_trigger
*trigger
,
3036 enum lttng_error_code
*_cmd_reply
)
3038 struct cds_lfht_iter iter
;
3039 struct cds_lfht_node
*triggers_ht_node
;
3040 struct lttng_channel_trigger_list
*trigger_list
;
3041 struct notification_client_list
*client_list
;
3042 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
3043 const struct lttng_condition
*condition
= lttng_trigger_get_const_condition(
3045 enum lttng_error_code cmd_reply
;
3049 cds_lfht_lookup(state
->triggers_ht
,
3050 lttng_condition_hash(condition
),
3054 triggers_ht_node
= cds_lfht_iter_get_node(&iter
);
3055 if (!triggers_ht_node
) {
3056 cmd_reply
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
3059 cmd_reply
= LTTNG_OK
;
3062 trigger_ht_element
= caa_container_of(triggers_ht_node
,
3063 struct lttng_trigger_ht_element
, node
);
3065 /* Remove trigger from channel_triggers_ht. */
3066 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
, trigger_list
,
3067 channel_triggers_ht_node
) {
3068 struct lttng_trigger_list_element
*trigger_element
, *tmp
;
3070 cds_list_for_each_entry_safe(trigger_element
, tmp
,
3071 &trigger_list
->list
, node
) {
3072 if (!lttng_trigger_is_equal(trigger
, trigger_element
->trigger
)) {
3076 DBG("Removed trigger from channel_triggers_ht");
3077 cds_list_del(&trigger_element
->node
);
3078 /* A trigger can only appear once per channel */
3083 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
3084 teardown_tracer_notifier(state
, trigger
);
3087 if (is_trigger_action_notify(trigger
)) {
3089 * Remove and release the client list from
3090 * notification_trigger_clients_ht.
3092 client_list
= get_client_list_from_condition(state
, condition
);
3093 LTTNG_ASSERT(client_list
);
3095 pthread_mutex_lock(&client_list
->lock
);
3096 cds_list_del(&trigger_ht_element
->client_list_trigger_node
);
3097 pthread_mutex_unlock(&client_list
->lock
);
3099 /* Put new reference and the hashtable's reference. */
3100 notification_client_list_put(client_list
);
3101 notification_client_list_put(client_list
);
3105 /* Remove trigger from triggers_ht. */
3106 notif_thread_state_remove_trigger_ht_elem(state
, trigger_ht_element
);
3108 /* Release the ownership of the trigger. */
3109 lttng_trigger_destroy(trigger_ht_element
->trigger
);
3110 call_rcu(&trigger_ht_element
->rcu_node
, free_lttng_trigger_ht_element_rcu
);
3114 *_cmd_reply
= cmd_reply
;
3119 /* Returns 0 on success, 1 on exit requested, negative value on error. */
3120 int handle_notification_thread_command(
3121 struct notification_thread_handle
*handle
,
3122 struct notification_thread_state
*state
)
3126 struct notification_thread_command
*cmd
;
3128 /* Read the event pipe to put it back into a quiescent state. */
3129 ret
= lttng_read(lttng_pipe_get_readfd(handle
->cmd_queue
.event_pipe
), &counter
,
3131 if (ret
!= sizeof(counter
)) {
3135 pthread_mutex_lock(&handle
->cmd_queue
.lock
);
3136 cmd
= cds_list_first_entry(&handle
->cmd_queue
.list
,
3137 struct notification_thread_command
, cmd_list_node
);
3138 cds_list_del(&cmd
->cmd_list_node
);
3139 pthread_mutex_unlock(&handle
->cmd_queue
.lock
);
3141 DBG("Received `%s` command",
3142 notification_command_type_str(cmd
->type
));
3143 switch (cmd
->type
) {
3144 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
3145 ret
= handle_notification_thread_command_register_trigger(state
,
3146 cmd
->parameters
.register_trigger
.trigger
,
3147 cmd
->parameters
.register_trigger
.is_trigger_anonymous
,
3150 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
3151 ret
= handle_notification_thread_command_unregister_trigger(
3153 cmd
->parameters
.unregister_trigger
.trigger
,
3156 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
3157 ret
= handle_notification_thread_command_add_channel(
3159 cmd
->parameters
.add_channel
.session
.name
,
3160 cmd
->parameters
.add_channel
.session
.uid
,
3161 cmd
->parameters
.add_channel
.session
.gid
,
3162 cmd
->parameters
.add_channel
.channel
.name
,
3163 cmd
->parameters
.add_channel
.channel
.domain
,
3164 cmd
->parameters
.add_channel
.channel
.key
,
3165 cmd
->parameters
.add_channel
.channel
.capacity
,
3168 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
3169 ret
= handle_notification_thread_command_remove_channel(
3170 state
, cmd
->parameters
.remove_channel
.key
,
3171 cmd
->parameters
.remove_channel
.domain
,
3174 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
3175 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
3176 ret
= handle_notification_thread_command_session_rotation(
3179 cmd
->parameters
.session_rotation
.session_name
,
3180 cmd
->parameters
.session_rotation
.uid
,
3181 cmd
->parameters
.session_rotation
.gid
,
3182 cmd
->parameters
.session_rotation
.trace_archive_chunk_id
,
3183 cmd
->parameters
.session_rotation
.location
,
3186 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
3187 ret
= handle_notification_thread_command_add_tracer_event_source(
3189 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3190 cmd
->parameters
.tracer_event_source
.domain
,
3193 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
3194 ret
= handle_notification_thread_command_remove_tracer_event_source(
3196 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3199 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
3201 struct lttng_triggers
*triggers
= NULL
;
3203 ret
= handle_notification_thread_command_list_triggers(
3206 cmd
->parameters
.list_triggers
.uid
,
3209 cmd
->reply
.list_triggers
.triggers
= triggers
;
3213 case NOTIFICATION_COMMAND_TYPE_QUIT
:
3214 cmd
->reply_code
= LTTNG_OK
;
3217 case NOTIFICATION_COMMAND_TYPE_GET_TRIGGER
:
3219 struct lttng_trigger
*trigger
= NULL
;
3221 ret
= handle_notification_thread_command_get_trigger(state
,
3222 cmd
->parameters
.get_trigger
.trigger
, &trigger
,
3224 cmd
->reply
.get_trigger
.trigger
= trigger
;
3227 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
3229 const enum client_transmission_status client_status
=
3230 cmd
->parameters
.client_communication_update
3232 const notification_client_id client_id
=
3233 cmd
->parameters
.client_communication_update
.id
;
3234 struct notification_client
*client
;
3237 client
= get_client_from_id(client_id
, state
);
3241 * Client error was probably already picked-up by the
3242 * notification thread or it has disconnected
3243 * gracefully while this command was queued.
3245 DBG("Failed to find notification client to update communication status, client id = %" PRIu64
,
3249 ret
= client_handle_transmission_status(
3250 client
, client_status
, state
);
3256 ERR("Unknown internal command received");
3264 if (cmd
->is_async
) {
3268 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3272 /* Wake-up and return a fatal error to the calling thread. */
3273 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3274 cmd
->reply_code
= LTTNG_ERR_FATAL
;
3276 /* Indicate a fatal error to the caller. */
3281 int socket_set_non_blocking(int socket
)
3285 /* Set the pipe as non-blocking. */
3286 ret
= fcntl(socket
, F_GETFL
, 0);
3288 PERROR("fcntl get socket flags");
3293 ret
= fcntl(socket
, F_SETFL
, flags
| O_NONBLOCK
);
3295 PERROR("fcntl set O_NONBLOCK socket flag");
3298 DBG("Client socket (fd = %i) set as non-blocking", socket
);
3304 int client_reset_inbound_state(struct notification_client
*client
)
3309 lttng_payload_clear(&client
->communication
.inbound
.payload
);
3311 client
->communication
.inbound
.bytes_to_receive
=
3312 sizeof(struct lttng_notification_channel_message
);
3313 client
->communication
.inbound
.msg_type
=
3314 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
;
3315 LTTNG_SOCK_SET_UID_CRED(&client
->communication
.inbound
.creds
, -1);
3316 LTTNG_SOCK_SET_GID_CRED(&client
->communication
.inbound
.creds
, -1);
3317 ret
= lttng_dynamic_buffer_set_size(
3318 &client
->communication
.inbound
.payload
.buffer
,
3319 client
->communication
.inbound
.bytes_to_receive
);
3324 int handle_notification_thread_client_connect(
3325 struct notification_thread_state
*state
)
3328 struct notification_client
*client
;
3330 DBG("Handling new notification channel client connection");
3332 client
= (notification_client
*) zmalloc(sizeof(*client
));
3339 pthread_mutex_init(&client
->lock
, NULL
);
3340 client
->id
= state
->next_notification_client_id
++;
3341 CDS_INIT_LIST_HEAD(&client
->condition_list
);
3342 lttng_payload_init(&client
->communication
.inbound
.payload
);
3343 lttng_payload_init(&client
->communication
.outbound
.payload
);
3344 client
->communication
.inbound
.expect_creds
= true;
3346 ret
= client_reset_inbound_state(client
);
3348 ERR("Failed to reset client communication's inbound state");
3353 ret
= lttcomm_accept_unix_sock(state
->notification_channel_socket
);
3355 ERR("Failed to accept new notification channel client connection");
3360 client
->socket
= ret
;
3362 ret
= socket_set_non_blocking(client
->socket
);
3364 ERR("Failed to set new notification channel client connection socket as non-blocking");
3368 ret
= lttcomm_setsockopt_creds_unix_sock(client
->socket
);
3370 ERR("Failed to set socket options on new notification channel client socket");
3375 ret
= lttng_poll_add(&state
->events
, client
->socket
,
3376 LPOLLIN
| LPOLLERR
|
3377 LPOLLHUP
| LPOLLRDHUP
);
3379 ERR("Failed to add notification channel client socket to poll set");
3383 DBG("Added new notification channel client socket (%i) to poll set",
3387 cds_lfht_add(state
->client_socket_ht
,
3388 hash_client_socket(client
->socket
),
3389 &client
->client_socket_ht_node
);
3390 cds_lfht_add(state
->client_id_ht
,
3391 hash_client_id(client
->id
),
3392 &client
->client_id_ht_node
);
3398 notification_client_destroy(client
);
3403 * RCU read-lock must be held by the caller.
3404 * Client lock must _not_ be held by the caller.
3407 int notification_thread_client_disconnect(
3408 struct notification_client
*client
,
3409 struct notification_thread_state
*state
)
3412 struct lttng_condition_list_element
*condition_list_element
, *tmp
;
3414 ASSERT_RCU_READ_LOCKED();
3416 /* Acquire the client lock to disable its communication atomically. */
3417 pthread_mutex_lock(&client
->lock
);
3418 client
->communication
.active
= false;
3419 cds_lfht_del(state
->client_socket_ht
, &client
->client_socket_ht_node
);
3420 cds_lfht_del(state
->client_id_ht
, &client
->client_id_ht_node
);
3421 pthread_mutex_unlock(&client
->lock
);
3423 ret
= lttng_poll_del(&state
->events
, client
->socket
);
3425 ERR("Failed to remove client socket %d from poll set",
3429 /* Release all conditions to which the client was subscribed. */
3430 cds_list_for_each_entry_safe(condition_list_element
, tmp
,
3431 &client
->condition_list
, node
) {
3432 (void) notification_thread_client_unsubscribe(client
,
3433 condition_list_element
->condition
, state
, NULL
);
3437 * Client no longer accessible to other threads (through the
3440 notification_client_destroy(client
);
3444 int handle_notification_thread_client_disconnect(
3445 int client_socket
, struct notification_thread_state
*state
)
3448 struct notification_client
*client
;
3451 DBG("Closing client connection (socket fd = %i)",
3453 client
= get_client_from_socket(client_socket
, state
);
3455 /* Internal state corruption, fatal error. */
3456 ERR("Unable to find client (socket fd = %i)",
3462 ret
= notification_thread_client_disconnect(client
, state
);
3468 int handle_notification_thread_client_disconnect_all(
3469 struct notification_thread_state
*state
)
3471 struct cds_lfht_iter iter
;
3472 struct notification_client
*client
;
3473 bool error_encoutered
= false;
3476 DBG("Closing all client connections");
3477 cds_lfht_for_each_entry(state
->client_socket_ht
, &iter
, client
,
3478 client_socket_ht_node
) {
3481 ret
= notification_thread_client_disconnect(
3484 error_encoutered
= true;
3488 return error_encoutered
? 1 : 0;
3491 int handle_notification_thread_trigger_unregister_all(
3492 struct notification_thread_state
*state
)
3494 bool error_occurred
= false;
3495 struct cds_lfht_iter iter
;
3496 struct lttng_trigger_ht_element
*trigger_ht_element
;
3499 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
3501 int ret
= handle_notification_thread_command_unregister_trigger(
3502 state
, trigger_ht_element
->trigger
, NULL
);
3504 error_occurred
= true;
3508 return error_occurred
? -1 : 0;
3512 int client_handle_transmission_status(
3513 struct notification_client
*client
,
3514 enum client_transmission_status transmission_status
,
3515 struct notification_thread_state
*state
)
3519 switch (transmission_status
) {
3520 case CLIENT_TRANSMISSION_STATUS_COMPLETE
:
3521 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3522 CLIENT_POLL_MASK_IN
);
3528 case CLIENT_TRANSMISSION_STATUS_QUEUED
:
3530 * We want to be notified whenever there is buffer space
3531 * available to send the rest of the payload.
3533 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3534 CLIENT_POLL_MASK_IN_OUT
);
3539 case CLIENT_TRANSMISSION_STATUS_FAIL
:
3540 ret
= notification_thread_client_disconnect(client
, state
);
3545 case CLIENT_TRANSMISSION_STATUS_ERROR
:
3555 /* Client lock must be acquired by caller. */
3557 enum client_transmission_status
client_flush_outgoing_queue(
3558 struct notification_client
*client
)
3561 size_t to_send_count
;
3562 enum client_transmission_status status
;
3563 struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3564 &client
->communication
.outbound
.payload
, 0, -1);
3565 const int fds_to_send_count
=
3566 lttng_payload_view_get_fd_handle_count(&pv
);
3568 ASSERT_LOCKED(client
->lock
);
3570 if (!client
->communication
.active
) {
3571 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3575 if (pv
.buffer
.size
== 0) {
3577 * If both data and fds are equal to zero, we are in an invalid
3580 LTTNG_ASSERT(fds_to_send_count
!= 0);
3585 to_send_count
= pv
.buffer
.size
;
3586 DBG("Flushing client (socket fd = %i) outgoing queue",
3589 ret
= lttcomm_send_unix_sock_non_block(client
->socket
,
3592 if ((ret
>= 0 && ret
< to_send_count
)) {
3593 DBG("Client (socket fd = %i) outgoing queue could not be completely flushed",
3595 to_send_count
-= std::max(ret
, (ssize_t
) 0);
3597 memmove(client
->communication
.outbound
.payload
.buffer
.data
,
3599 pv
.buffer
.size
- to_send_count
,
3601 ret
= lttng_dynamic_buffer_set_size(
3602 &client
->communication
.outbound
.payload
.buffer
,
3608 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3610 } else if (ret
< 0) {
3611 /* Generic error, disable the client's communication. */
3612 ERR("Failed to flush outgoing queue, disconnecting client (socket fd = %i)",
3614 client
->communication
.active
= false;
3615 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3619 * No error and flushed the queue completely.
3621 * The payload buffer size is used later to
3622 * check if there is notifications queued. So albeit that the
3623 * direct caller knows that the transmission is complete, we
3624 * need to set the buffer size to zero.
3626 ret
= lttng_dynamic_buffer_set_size(
3627 &client
->communication
.outbound
.payload
.buffer
, 0);
3634 /* No fds to send, transmission is complete. */
3635 if (fds_to_send_count
== 0) {
3636 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3640 ret
= lttcomm_send_payload_view_fds_unix_sock_non_block(
3641 client
->socket
, &pv
);
3643 /* Generic error, disable the client's communication. */
3644 ERR("Failed to flush outgoing fds queue, disconnecting client (socket fd = %i)",
3646 client
->communication
.active
= false;
3647 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3649 } else if (ret
== 0) {
3650 /* Nothing could be sent. */
3651 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3653 /* Fd passing is an all or nothing kind of thing. */
3654 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3656 * The payload _fd_array count is used later to
3657 * check if there is notifications queued. So although the
3658 * direct caller knows that the transmission is complete, we
3659 * need to clear the _fd_array for the queuing check.
3661 lttng_dynamic_pointer_array_clear(
3662 &client
->communication
.outbound
.payload
3667 if (status
== CLIENT_TRANSMISSION_STATUS_COMPLETE
) {
3668 client
->communication
.outbound
.queued_command_reply
= false;
3669 client
->communication
.outbound
.dropped_notification
= false;
3670 lttng_payload_clear(&client
->communication
.outbound
.payload
);
3675 return CLIENT_TRANSMISSION_STATUS_ERROR
;
3679 bool client_has_outbound_data_left(
3680 const struct notification_client
*client
)
3682 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3683 &client
->communication
.outbound
.payload
, 0, -1);
3684 const bool has_data
= pv
.buffer
.size
!= 0;
3685 const bool has_fds
= lttng_payload_view_get_fd_handle_count(&pv
);
3687 return has_data
|| has_fds
;
3690 /* Client lock must _not_ be held by the caller. */
3692 int client_send_command_reply(struct notification_client
*client
,
3693 struct notification_thread_state
*state
,
3694 enum lttng_notification_channel_status status
)
3697 struct lttng_notification_channel_command_reply reply
= {
3698 .status
= (int8_t) status
,
3700 struct lttng_notification_channel_message msg
= {
3701 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY
,
3702 .size
= sizeof(reply
),
3704 char buffer
[sizeof(msg
) + sizeof(reply
)];
3705 enum client_transmission_status transmission_status
;
3707 memcpy(buffer
, &msg
, sizeof(msg
));
3708 memcpy(buffer
+ sizeof(msg
), &reply
, sizeof(reply
));
3709 DBG("Send command reply (%i)", (int) status
);
3711 pthread_mutex_lock(&client
->lock
);
3712 if (client
->communication
.outbound
.queued_command_reply
) {
3713 /* Protocol error. */
3717 /* Enqueue buffer to outgoing queue and flush it. */
3718 ret
= lttng_dynamic_buffer_append(
3719 &client
->communication
.outbound
.payload
.buffer
,
3720 buffer
, sizeof(buffer
));
3725 transmission_status
= client_flush_outgoing_queue(client
);
3727 if (client_has_outbound_data_left(client
)) {
3728 /* Queue could not be emptied. */
3729 client
->communication
.outbound
.queued_command_reply
= true;
3732 pthread_mutex_unlock(&client
->lock
);
3733 ret
= client_handle_transmission_status(
3734 client
, transmission_status
, state
);
3741 pthread_mutex_unlock(&client
->lock
);
3747 int client_handle_message_unknown(struct notification_client
*client
,
3748 struct notification_thread_state
*state
__attribute__((unused
)))
3752 * Receiving message header. The function will be called again
3753 * once the rest of the message as been received and can be
3756 const struct lttng_notification_channel_message
*msg
;
3758 LTTNG_ASSERT(sizeof(*msg
) == client
->communication
.inbound
.payload
.buffer
.size
);
3759 msg
= (const struct lttng_notification_channel_message
*)
3760 client
->communication
.inbound
.payload
.buffer
.data
;
3762 if (msg
->size
== 0 ||
3763 msg
->size
> DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE
) {
3764 ERR("Invalid notification channel message: length = %u",
3770 switch (msg
->type
) {
3771 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3772 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3773 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3777 ERR("Invalid notification channel message: unexpected message type");
3781 client
->communication
.inbound
.bytes_to_receive
= msg
->size
;
3782 client
->communication
.inbound
.fds_to_receive
= msg
->fds
;
3783 client
->communication
.inbound
.msg_type
=
3784 (enum lttng_notification_channel_message_type
) msg
->type
;
3785 ret
= lttng_dynamic_buffer_set_size(
3786 &client
->communication
.inbound
.payload
.buffer
, msg
->size
);
3788 /* msg is not valid anymore due to lttng_dynamic_buffer_set_size. */
3795 int client_handle_message_handshake(struct notification_client
*client
,
3796 struct notification_thread_state
*state
)
3799 struct lttng_notification_channel_command_handshake
*handshake_client
;
3800 const struct lttng_notification_channel_command_handshake handshake_reply
= {
3801 .major
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
,
3802 .minor
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR
,
3804 const struct lttng_notification_channel_message msg_header
= {
3805 .type
= LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
,
3806 .size
= sizeof(handshake_reply
),
3808 enum lttng_notification_channel_status status
=
3809 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3810 char send_buffer
[sizeof(msg_header
) + sizeof(handshake_reply
)];
3812 memcpy(send_buffer
, &msg_header
, sizeof(msg_header
));
3813 memcpy(send_buffer
+ sizeof(msg_header
), &handshake_reply
,
3814 sizeof(handshake_reply
));
3817 (struct lttng_notification_channel_command_handshake
*)
3818 client
->communication
.inbound
.payload
.buffer
3820 client
->major
= handshake_client
->major
;
3821 client
->minor
= handshake_client
->minor
;
3822 if (!client
->communication
.inbound
.creds_received
) {
3823 ERR("No credentials received from client");
3828 client
->uid
= LTTNG_SOCK_GET_UID_CRED(
3829 &client
->communication
.inbound
.creds
);
3830 client
->gid
= LTTNG_SOCK_GET_GID_CRED(
3831 &client
->communication
.inbound
.creds
);
3832 client
->is_sessiond
= LTTNG_SOCK_GET_PID_CRED(&client
->communication
.inbound
.creds
) == getpid();
3833 DBG("Received handshake from client: uid = %u, gid = %u, protocol version = %i.%i, client is sessiond = %s",
3834 client
->uid
, client
->gid
, (int) client
->major
,
3835 (int) client
->minor
,
3836 client
->is_sessiond
? "true" : "false");
3838 if (handshake_client
->major
!=
3839 LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
) {
3840 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION
;
3843 pthread_mutex_lock(&client
->lock
);
3844 /* Outgoing queue will be flushed when the command reply is sent. */
3845 ret
= lttng_dynamic_buffer_append(
3846 &client
->communication
.outbound
.payload
.buffer
, send_buffer
,
3847 sizeof(send_buffer
));
3849 ERR("Failed to send protocol version to notification channel client");
3853 client
->validated
= true;
3854 client
->communication
.active
= true;
3855 pthread_mutex_unlock(&client
->lock
);
3857 /* Set reception state to receive the next message header. */
3858 ret
= client_reset_inbound_state(client
);
3860 ERR("Failed to reset client communication's inbound state");
3864 /* Flushes the outgoing queue. */
3865 ret
= client_send_command_reply(client
, state
, status
);
3867 ERR("Failed to send reply to notification channel client");
3873 pthread_mutex_unlock(&client
->lock
);
3879 int client_handle_message_subscription(
3880 struct notification_client
*client
,
3881 enum lttng_notification_channel_message_type msg_type
,
3882 struct notification_thread_state
*state
)
3885 struct lttng_condition
*condition
;
3886 enum lttng_notification_channel_status status
=
3887 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3888 struct lttng_payload_view condition_view
=
3889 lttng_payload_view_from_payload(
3890 &client
->communication
.inbound
.payload
,
3892 size_t expected_condition_size
;
3895 * No need to lock client to sample the inbound state as the only
3896 * other thread accessing clients (action executor) only uses the
3899 expected_condition_size
= client
->communication
.inbound
.payload
.buffer
.size
;
3900 ret
= lttng_condition_create_from_payload(&condition_view
, &condition
);
3901 if (ret
!= expected_condition_size
) {
3902 ERR("Malformed condition received from client");
3906 /* Ownership of condition is always transferred. */
3907 if (msg_type
== LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
) {
3908 ret
= notification_thread_client_subscribe(
3909 client
, condition
, state
, &status
);
3911 ret
= notification_thread_client_unsubscribe(
3912 client
, condition
, state
, &status
);
3919 /* Set reception state to receive the next message header. */
3920 ret
= client_reset_inbound_state(client
);
3922 ERR("Failed to reset client communication's inbound state");
3926 ret
= client_send_command_reply(client
, state
, status
);
3928 ERR("Failed to send reply to notification channel client");
3937 int client_dispatch_message(struct notification_client
*client
,
3938 struct notification_thread_state
*state
)
3942 if (client
->communication
.inbound
.msg_type
!=
3943 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
&&
3944 client
->communication
.inbound
.msg_type
!=
3945 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
&&
3946 !client
->validated
) {
3947 WARN("client attempted a command before handshake");
3952 switch (client
->communication
.inbound
.msg_type
) {
3953 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
:
3955 ret
= client_handle_message_unknown(client
, state
);
3958 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3960 ret
= client_handle_message_handshake(client
, state
);
3963 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3964 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3966 ret
= client_handle_message_subscription(client
,
3967 client
->communication
.inbound
.msg_type
, state
);
3977 /* Incoming data from client. */
3978 int handle_notification_thread_client_in(
3979 struct notification_thread_state
*state
, int socket
)
3982 struct notification_client
*client
;
3987 client
= get_client_from_socket(socket
, state
);
3989 /* Internal error, abort. */
3994 if (client
->communication
.inbound
.bytes_to_receive
== 0 &&
3995 client
->communication
.inbound
.fds_to_receive
!= 0) {
3996 /* Only FDs left to receive. */
4000 offset
= client
->communication
.inbound
.payload
.buffer
.size
-
4001 client
->communication
.inbound
.bytes_to_receive
;
4002 if (client
->communication
.inbound
.expect_creds
) {
4003 recv_ret
= lttcomm_recv_creds_unix_sock(socket
,
4004 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
4005 client
->communication
.inbound
.bytes_to_receive
,
4006 &client
->communication
.inbound
.creds
);
4008 client
->communication
.inbound
.expect_creds
= false;
4009 client
->communication
.inbound
.creds_received
= true;
4012 recv_ret
= lttcomm_recv_unix_sock_non_block(socket
,
4013 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
4014 client
->communication
.inbound
.bytes_to_receive
);
4016 if (recv_ret
>= 0) {
4017 client
->communication
.inbound
.bytes_to_receive
-= recv_ret
;
4019 goto error_disconnect_client
;
4022 if (client
->communication
.inbound
.bytes_to_receive
!= 0) {
4023 /* Message incomplete wait for more data. */
4029 LTTNG_ASSERT(client
->communication
.inbound
.bytes_to_receive
== 0);
4032 if (client
->communication
.inbound
.fds_to_receive
!= 0) {
4033 ret
= lttcomm_recv_payload_fds_unix_sock_non_block(
4035 client
->communication
.inbound
.fds_to_receive
,
4036 &client
->communication
.inbound
.payload
);
4039 * Fds received. non blocking fds passing is all
4042 ssize_t expected_size
;
4044 expected_size
= sizeof(int) *
4045 client
->communication
.inbound
4047 LTTNG_ASSERT(ret
== expected_size
);
4048 client
->communication
.inbound
.fds_to_receive
= 0;
4049 } else if (ret
== 0) {
4050 /* Received nothing. */
4054 goto error_disconnect_client
;
4058 /* At this point the message is complete.*/
4059 LTTNG_ASSERT(client
->communication
.inbound
.bytes_to_receive
== 0 &&
4060 client
->communication
.inbound
.fds_to_receive
== 0);
4061 ret
= client_dispatch_message(client
, state
);
4064 * Only returns an error if this client must be
4067 goto error_disconnect_client
;
4074 error_disconnect_client
:
4075 ret
= notification_thread_client_disconnect(client
, state
);
4079 /* Client ready to receive outgoing data. */
4080 int handle_notification_thread_client_out(
4081 struct notification_thread_state
*state
, int socket
)
4084 struct notification_client
*client
;
4085 enum client_transmission_status transmission_status
;
4088 client
= get_client_from_socket(socket
, state
);
4090 /* Internal error, abort. */
4095 pthread_mutex_lock(&client
->lock
);
4096 transmission_status
= client_flush_outgoing_queue(client
);
4097 pthread_mutex_unlock(&client
->lock
);
4099 ret
= client_handle_transmission_status(
4100 client
, transmission_status
, state
);
4110 bool evaluate_buffer_usage_condition(const struct lttng_condition
*condition
,
4111 const struct channel_state_sample
*sample
,
4112 uint64_t buffer_capacity
)
4114 bool result
= false;
4116 enum lttng_condition_type condition_type
;
4117 const struct lttng_condition_buffer_usage
*use_condition
= container_of(
4118 condition
, struct lttng_condition_buffer_usage
,
4121 if (use_condition
->threshold_bytes
.set
) {
4122 threshold
= use_condition
->threshold_bytes
.value
;
4125 * Threshold was expressed as a ratio.
4127 * TODO the threshold (in bytes) of conditions expressed
4128 * as a ratio of total buffer size could be cached to
4129 * forego this double-multiplication or it could be performed
4130 * as fixed-point math.
4132 * Note that caching should accommodates the case where the
4133 * condition applies to multiple channels (i.e. don't assume
4134 * that all channels matching my_chann* have the same size...)
4136 threshold
= (uint64_t) (use_condition
->threshold_ratio
.value
*
4137 (double) buffer_capacity
);
4140 condition_type
= lttng_condition_get_type(condition
);
4141 if (condition_type
== LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
) {
4142 DBG("Low buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4143 threshold
, sample
->highest_usage
);
4146 * The low condition should only be triggered once _all_ of the
4147 * streams in a channel have gone below the "low" threshold.
4149 if (sample
->highest_usage
<= threshold
) {
4153 DBG("High buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4154 threshold
, sample
->highest_usage
);
4157 * For high buffer usage scenarios, we want to trigger whenever
4158 * _any_ of the streams has reached the "high" threshold.
4160 if (sample
->highest_usage
>= threshold
) {
4169 bool evaluate_session_consumed_size_condition(
4170 const struct lttng_condition
*condition
,
4171 uint64_t session_consumed_size
)
4174 const struct lttng_condition_session_consumed_size
*size_condition
=
4175 container_of(condition
,
4176 struct lttng_condition_session_consumed_size
,
4179 threshold
= size_condition
->consumed_threshold_bytes
.value
;
4180 DBG("Session consumed size condition being evaluated: threshold = %" PRIu64
", current size = %" PRIu64
,
4181 threshold
, session_consumed_size
);
4182 return session_consumed_size
>= threshold
;
4186 int evaluate_buffer_condition(const struct lttng_condition
*condition
,
4187 struct lttng_evaluation
**evaluation
,
4188 const struct notification_thread_state
*state
__attribute__((unused
)),
4189 const struct channel_state_sample
*previous_sample
,
4190 const struct channel_state_sample
*latest_sample
,
4191 uint64_t previous_session_consumed_total
,
4192 uint64_t latest_session_consumed_total
,
4193 struct channel_info
*channel_info
)
4196 enum lttng_condition_type condition_type
;
4197 const bool previous_sample_available
= !!previous_sample
;
4198 bool previous_sample_result
= false;
4199 bool latest_sample_result
;
4201 condition_type
= lttng_condition_get_type(condition
);
4203 switch (condition_type
) {
4204 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4205 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4206 if (caa_likely(previous_sample_available
)) {
4207 previous_sample_result
=
4208 evaluate_buffer_usage_condition(condition
,
4209 previous_sample
, channel_info
->capacity
);
4211 latest_sample_result
= evaluate_buffer_usage_condition(
4212 condition
, latest_sample
,
4213 channel_info
->capacity
);
4215 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
4216 if (caa_likely(previous_sample_available
)) {
4217 previous_sample_result
=
4218 evaluate_session_consumed_size_condition(
4220 previous_session_consumed_total
);
4222 latest_sample_result
=
4223 evaluate_session_consumed_size_condition(
4225 latest_session_consumed_total
);
4228 /* Unknown condition type; internal error. */
4232 if (!latest_sample_result
||
4233 (previous_sample_result
== latest_sample_result
)) {
4235 * Only trigger on a condition evaluation transition.
4237 * NOTE: This edge-triggered logic may not be appropriate for
4238 * future condition types.
4243 if (!evaluation
|| !latest_sample_result
) {
4247 switch (condition_type
) {
4248 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4249 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4250 *evaluation
= lttng_evaluation_buffer_usage_create(
4252 latest_sample
->highest_usage
,
4253 channel_info
->capacity
);
4255 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
4256 *evaluation
= lttng_evaluation_session_consumed_size_create(
4257 latest_session_consumed_total
);
4272 int client_notification_overflow(struct notification_client
*client
)
4275 const struct lttng_notification_channel_message msg
= {
4276 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED
,
4279 ASSERT_LOCKED(client
->lock
);
4281 DBG("Dropping notification addressed to client (socket fd = %i)",
4283 if (client
->communication
.outbound
.dropped_notification
) {
4285 * The client already has a "notification dropped" message
4286 * in its outgoing queue. Nothing to do since all
4287 * of those messages are coalesced.
4292 client
->communication
.outbound
.dropped_notification
= true;
4293 ret
= lttng_dynamic_buffer_append(
4294 &client
->communication
.outbound
.payload
.buffer
, &msg
,
4297 PERROR("Failed to enqueue \"dropped notification\" message in client's (socket fd = %i) outgoing queue",
4304 static int client_handle_transmission_status_wrapper(
4305 struct notification_client
*client
,
4306 enum client_transmission_status status
,
4309 return client_handle_transmission_status(client
, status
,
4310 (struct notification_thread_state
*) user_data
);
4314 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
4315 const struct lttng_evaluation
*evaluation
,
4316 struct notification_client_list
* client_list
,
4317 struct notification_thread_state
*state
,
4318 uid_t object_uid
, gid_t object_gid
)
4320 const struct lttng_credentials creds
= {
4321 .uid
= LTTNG_OPTIONAL_INIT_VALUE(object_uid
),
4322 .gid
= LTTNG_OPTIONAL_INIT_VALUE(object_gid
),
4325 return notification_client_list_send_evaluation(client_list
,
4326 trigger
, evaluation
,
4328 client_handle_transmission_status_wrapper
, state
);
4332 * Permission checks relative to notification channel clients are performed
4333 * here. Notice how object, client, and trigger credentials are involved in
4336 * The `object` credentials are the credentials associated with the "subject"
4337 * of a condition. For instance, a `rotation completed` condition applies
4338 * to a session. When that condition is met, it will produce an evaluation
4339 * against a session. Hence, in this case, the `object` credentials are the
4340 * credentials of the "subject" session.
4342 * The `trigger` credentials are the credentials of the user that registered the
4345 * The `client` credentials are the credentials of the user that created a given
4346 * notification channel.
4348 * In terms of visibility, it is expected that non-privilieged users can only
4349 * register triggers against "their" objects (their own sessions and
4350 * applications they are allowed to interact with). They can then open a
4351 * notification channel and subscribe to notifications associated with those
4354 * As for privilieged users, they can register triggers against the objects of
4355 * other users. They can then subscribe to the notifications associated to their
4356 * triggers. Privilieged users _can't_ subscribe to the notifications of
4357 * triggers owned by other users; they must create their own triggers.
4359 * This is more a concern of usability than security. It would be difficult for
4360 * a root user reliably subscribe to a specific set of conditions without
4361 * interference from external users (those could, for instance, unregister
4364 int notification_client_list_send_evaluation(
4365 struct notification_client_list
*client_list
,
4366 const struct lttng_trigger
*trigger
,
4367 const struct lttng_evaluation
*evaluation
,
4368 const struct lttng_credentials
*source_object_creds
,
4369 report_client_transmission_result_cb client_report
,
4373 struct lttng_payload msg_payload
;
4374 struct notification_client_list_element
*client_list_element
, *tmp
;
4375 const struct lttng_notification notification
= {
4376 .trigger
= (struct lttng_trigger
*) trigger
,
4377 .evaluation
= (struct lttng_evaluation
*) evaluation
,
4379 struct lttng_notification_channel_message msg_header
= {
4380 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION
,
4382 const struct lttng_credentials
*trigger_creds
=
4383 lttng_trigger_get_credentials(trigger
);
4385 lttng_payload_init(&msg_payload
);
4387 ret
= lttng_dynamic_buffer_append(&msg_payload
.buffer
, &msg_header
,
4388 sizeof(msg_header
));
4393 ret
= lttng_notification_serialize(¬ification
, &msg_payload
);
4395 ERR("Failed to serialize notification");
4400 /* Update payload size. */
4401 ((struct lttng_notification_channel_message
*) msg_payload
.buffer
.data
)
4402 ->size
= (uint32_t)(
4403 msg_payload
.buffer
.size
- sizeof(msg_header
));
4405 /* Update the payload number of fds. */
4407 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
4408 &msg_payload
, 0, -1);
4410 ((struct lttng_notification_channel_message
*)
4411 msg_payload
.buffer
.data
)->fds
= (uint32_t)
4412 lttng_payload_view_get_fd_handle_count(&pv
);
4415 pthread_mutex_lock(&client_list
->lock
);
4416 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4417 &client_list
->clients_list
, node
) {
4418 enum client_transmission_status transmission_status
;
4419 struct notification_client
*client
=
4420 client_list_element
->client
;
4423 pthread_mutex_lock(&client
->lock
);
4424 if (!client
->communication
.active
) {
4426 * Skip inactive client (protocol error or
4429 DBG("Skipping client at it is marked as inactive");
4433 if (lttng_trigger_is_hidden(trigger
) && !client
->is_sessiond
) {
4435 * Notifications resulting from an hidden trigger are
4436 * only sent to the session daemon.
4438 DBG("Skipping client as the trigger is hidden and the client is not the session daemon");
4442 if (source_object_creds
) {
4443 if (client
->uid
!= lttng_credentials_get_uid(source_object_creds
) &&
4444 client
->gid
!= lttng_credentials_get_gid(source_object_creds
) &&
4447 * Client is not allowed to monitor this
4450 DBG("Skipping client at it does not have the object permission to receive notification for this trigger");
4455 if (client
->uid
!= lttng_credentials_get_uid(trigger_creds
)) {
4456 DBG("Skipping client at it does not have the permission to receive notification for this trigger");
4460 DBG("Sending notification to client (fd = %i, %zu bytes)",
4461 client
->socket
, msg_payload
.buffer
.size
);
4463 if (client_has_outbound_data_left(client
)) {
4465 * Outgoing data is already buffered for this client;
4466 * drop the notification and enqueue a "dropped
4467 * notification" message if this is the first dropped
4468 * notification since the socket spilled-over to the
4471 ret
= client_notification_overflow(client
);
4478 ret
= lttng_payload_copy(&msg_payload
, &client
->communication
.outbound
.payload
);
4484 transmission_status
= client_flush_outgoing_queue(client
);
4485 pthread_mutex_unlock(&client
->lock
);
4486 ret
= client_report(client
, transmission_status
, user_data
);
4489 goto end_unlock_list
;
4495 pthread_mutex_unlock(&client
->lock
);
4498 goto end_unlock_list
;
4504 pthread_mutex_unlock(&client_list
->lock
);
4506 lttng_payload_reset(&msg_payload
);
4511 struct lttng_event_notifier_notification
*recv_one_event_notifier_notification(
4512 int notification_pipe_read_fd
, enum lttng_domain_type domain
)
4516 struct lttng_event_notifier_notification
*notification
= NULL
;
4517 char *capture_buffer
= NULL
;
4518 size_t capture_buffer_size
;
4519 void *reception_buffer
;
4520 size_t reception_size
;
4522 struct lttng_ust_abi_event_notifier_notification ust_notification
;
4523 struct lttng_kernel_abi_event_notifier_notification kernel_notification
;
4525 /* Init lttng_event_notifier_notification */
4527 case LTTNG_DOMAIN_UST
:
4528 reception_buffer
= (void *) &ust_notification
;
4529 reception_size
= sizeof(ust_notification
);
4531 case LTTNG_DOMAIN_KERNEL
:
4532 reception_buffer
= (void *) &kernel_notification
;
4533 reception_size
= sizeof(kernel_notification
);
4540 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4541 * ensuring that read/write of tracer notifications are atomic.
4543 ret
= lttng_read(notification_pipe_read_fd
, reception_buffer
,
4545 if (ret
!= reception_size
) {
4546 PERROR("Failed to read from event source notification pipe: fd = %d, size to read = %zu, ret = %d",
4547 notification_pipe_read_fd
, reception_size
, ret
);
4553 case LTTNG_DOMAIN_UST
:
4554 token
= ust_notification
.token
;
4555 capture_buffer_size
= ust_notification
.capture_buf_size
;
4557 case LTTNG_DOMAIN_KERNEL
:
4558 token
= kernel_notification
.token
;
4559 capture_buffer_size
= kernel_notification
.capture_buf_size
;
4565 if (capture_buffer_size
== 0) {
4566 capture_buffer
= NULL
;
4570 if (capture_buffer_size
> MAX_CAPTURE_SIZE
) {
4571 ERR("Event notifier has a capture payload size which exceeds the maximum allowed size: capture_payload_size = %zu bytes, max allowed size = %d bytes",
4572 capture_buffer_size
, MAX_CAPTURE_SIZE
);
4576 capture_buffer
= (char *) zmalloc(capture_buffer_size
);
4577 if (!capture_buffer
) {
4578 ERR("Failed to allocate capture buffer");
4582 /* Fetch additional payload (capture). */
4583 ret
= lttng_read(notification_pipe_read_fd
, capture_buffer
, capture_buffer_size
);
4584 if (ret
!= capture_buffer_size
) {
4585 ERR("Failed to read from event source pipe (fd = %i)",
4586 notification_pipe_read_fd
);
4591 notification
= lttng_event_notifier_notification_create(token
, domain
,
4592 capture_buffer
, capture_buffer_size
);
4593 if (notification
== NULL
) {
4598 * Ownership transfered to the lttng_event_notifier_notification object.
4600 capture_buffer
= NULL
;
4603 free(capture_buffer
);
4604 return notification
;
4608 int dispatch_one_event_notifier_notification(struct notification_thread_state
*state
,
4609 struct lttng_event_notifier_notification
*notification
)
4611 struct cds_lfht_node
*node
;
4612 struct cds_lfht_iter iter
;
4613 struct notification_trigger_tokens_ht_element
*element
;
4614 struct lttng_evaluation
*evaluation
= NULL
;
4615 enum action_executor_status executor_status
;
4616 struct notification_client_list
*client_list
= NULL
;
4618 unsigned int capture_count
= 0;
4620 /* Find triggers associated with this token. */
4622 cds_lfht_lookup(state
->trigger_tokens_ht
,
4623 hash_key_u64(¬ification
->tracer_token
, lttng_ht_seed
),
4624 match_trigger_token
, ¬ification
->tracer_token
, &iter
);
4625 node
= cds_lfht_iter_get_node(&iter
);
4626 if (caa_unlikely(!node
)) {
4628 * This is not an error, slow consumption of the tracer
4629 * notifications can lead to situations where a trigger is
4630 * removed but we still get tracer notifications matching a
4631 * trigger that no longer exists.
4637 element
= caa_container_of(node
,
4638 struct notification_trigger_tokens_ht_element
,
4641 if (lttng_condition_event_rule_matches_get_capture_descriptor_count(
4642 lttng_trigger_get_const_condition(element
->trigger
),
4643 &capture_count
) != LTTNG_CONDITION_STATUS_OK
) {
4644 ERR("Failed to get capture count");
4649 if (!notification
->capture_buffer
&& capture_count
!= 0) {
4650 ERR("Expected capture but capture buffer is null");
4655 evaluation
= lttng_evaluation_event_rule_matches_create(
4656 container_of(lttng_trigger_get_const_condition(
4658 struct lttng_condition_event_rule_matches
,
4660 notification
->capture_buffer
,
4661 notification
->capture_buf_size
, false);
4663 if (evaluation
== NULL
) {
4664 ERR("Failed to create event rule matches evaluation while creating and enqueuing action executor job");
4669 client_list
= get_client_list_from_condition(state
,
4670 lttng_trigger_get_const_condition(element
->trigger
));
4671 executor_status
= action_executor_enqueue_trigger(state
->executor
,
4672 element
->trigger
, evaluation
, NULL
, client_list
);
4673 switch (executor_status
) {
4674 case ACTION_EXECUTOR_STATUS_OK
:
4677 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4679 struct notification_client_list_element
*client_list_element
,
4683 * Not a fatal error; this is expected and simply means the
4684 * executor has too much work queued already.
4688 /* No clients subscribed to notifications for this trigger. */
4693 /* Warn clients that a notification (or more) was dropped. */
4694 pthread_mutex_lock(&client_list
->lock
);
4695 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4696 &client_list
->clients_list
, node
) {
4697 enum client_transmission_status transmission_status
;
4698 struct notification_client
*client
=
4699 client_list_element
->client
;
4701 pthread_mutex_lock(&client
->lock
);
4702 ret
= client_notification_overflow(client
);
4708 transmission_status
=
4709 client_flush_outgoing_queue(client
);
4710 ret
= client_handle_transmission_status(
4711 client
, transmission_status
, state
);
4717 pthread_mutex_unlock(&client
->lock
);
4723 pthread_mutex_unlock(&client_list
->lock
);
4726 case ACTION_EXECUTOR_STATUS_INVALID
:
4727 case ACTION_EXECUTOR_STATUS_ERROR
:
4728 /* Fatal error, shut down everything. */
4729 ERR("Fatal error encoutered while enqueuing action to the action executor");
4733 /* Unhandled error. */
4738 notification_client_list_put(client_list
);
4745 int handle_one_event_notifier_notification(
4746 struct notification_thread_state
*state
,
4747 int pipe
, enum lttng_domain_type domain
)
4750 struct lttng_event_notifier_notification
*notification
= NULL
;
4752 notification
= recv_one_event_notifier_notification(pipe
, domain
);
4753 if (notification
== NULL
) {
4754 /* Reception failed, don't consider it fatal. */
4755 ERR("Error receiving an event notifier notification from tracer: fd = %i, domain = %s",
4756 pipe
, lttng_domain_type_str(domain
));
4760 ret
= dispatch_one_event_notifier_notification(state
, notification
);
4762 ERR("Error dispatching an event notifier notification from tracer: fd = %i, domain = %s",
4763 pipe
, lttng_domain_type_str(domain
));
4768 lttng_event_notifier_notification_destroy(notification
);
4772 int handle_notification_thread_event_notification(struct notification_thread_state
*state
,
4773 int pipe
, enum lttng_domain_type domain
)
4775 return handle_one_event_notifier_notification(state
, pipe
, domain
);
4778 int handle_notification_thread_channel_sample(
4779 struct notification_thread_state
*state
, int pipe
,
4780 enum lttng_domain_type domain
)
4783 struct lttcomm_consumer_channel_monitor_msg sample_msg
;
4784 struct channel_info
*channel_info
;
4785 struct cds_lfht_node
*node
;
4786 struct cds_lfht_iter iter
;
4787 struct lttng_channel_trigger_list
*trigger_list
;
4788 struct lttng_trigger_list_element
*trigger_list_element
;
4789 bool previous_sample_available
= false;
4790 struct channel_state_sample previous_sample
, latest_sample
;
4791 uint64_t previous_session_consumed_total
, latest_session_consumed_total
;
4792 struct lttng_credentials channel_creds
;
4795 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4796 * ensuring that read/write of sampling messages are atomic.
4798 ret
= lttng_read(pipe
, &sample_msg
, sizeof(sample_msg
));
4799 if (ret
!= sizeof(sample_msg
)) {
4800 ERR("Failed to read from monitoring pipe (fd = %i)",
4807 latest_sample
.key
.key
= sample_msg
.key
;
4808 latest_sample
.key
.domain
= domain
;
4809 latest_sample
.highest_usage
= sample_msg
.highest
;
4810 latest_sample
.lowest_usage
= sample_msg
.lowest
;
4811 latest_sample
.channel_total_consumed
= sample_msg
.total_consumed
;
4815 /* Retrieve the channel's informations */
4816 cds_lfht_lookup(state
->channels_ht
,
4817 hash_channel_key(&latest_sample
.key
),
4821 node
= cds_lfht_iter_get_node(&iter
);
4822 if (caa_unlikely(!node
)) {
4824 * Not an error since the consumer can push a sample to the pipe
4825 * and the rest of the session daemon could notify us of the
4826 * channel's destruction before we get a chance to process that
4829 DBG("Received a sample for an unknown channel from consumerd, key = %" PRIu64
" in %s domain",
4830 latest_sample
.key
.key
,
4831 lttng_domain_type_str(domain
));
4834 channel_info
= caa_container_of(node
, struct channel_info
,
4836 DBG("Handling channel sample for channel %s (key = %" PRIu64
") in session %s (highest usage = %" PRIu64
", lowest usage = %" PRIu64
", total consumed = %" PRIu64
")",
4838 latest_sample
.key
.key
,
4839 channel_info
->session_info
->name
,
4840 latest_sample
.highest_usage
,
4841 latest_sample
.lowest_usage
,
4842 latest_sample
.channel_total_consumed
);
4844 previous_session_consumed_total
=
4845 channel_info
->session_info
->consumed_data_size
;
4847 /* Retrieve the channel's last sample, if it exists, and update it. */
4848 cds_lfht_lookup(state
->channel_state_ht
,
4849 hash_channel_key(&latest_sample
.key
),
4850 match_channel_state_sample
,
4853 node
= cds_lfht_iter_get_node(&iter
);
4854 if (caa_likely(node
)) {
4855 struct channel_state_sample
*stored_sample
;
4857 /* Update the sample stored. */
4858 stored_sample
= caa_container_of(node
,
4859 struct channel_state_sample
,
4860 channel_state_ht_node
);
4862 memcpy(&previous_sample
, stored_sample
,
4863 sizeof(previous_sample
));
4864 stored_sample
->highest_usage
= latest_sample
.highest_usage
;
4865 stored_sample
->lowest_usage
= latest_sample
.lowest_usage
;
4866 stored_sample
->channel_total_consumed
= latest_sample
.channel_total_consumed
;
4867 previous_sample_available
= true;
4869 latest_session_consumed_total
=
4870 previous_session_consumed_total
+
4871 (latest_sample
.channel_total_consumed
- previous_sample
.channel_total_consumed
);
4874 * This is the channel's first sample, allocate space for and
4875 * store the new sample.
4877 struct channel_state_sample
*stored_sample
;
4879 stored_sample
= (channel_state_sample
*) zmalloc(sizeof(*stored_sample
));
4880 if (!stored_sample
) {
4885 memcpy(stored_sample
, &latest_sample
, sizeof(*stored_sample
));
4886 cds_lfht_node_init(&stored_sample
->channel_state_ht_node
);
4887 cds_lfht_add(state
->channel_state_ht
,
4888 hash_channel_key(&stored_sample
->key
),
4889 &stored_sample
->channel_state_ht_node
);
4891 latest_session_consumed_total
=
4892 previous_session_consumed_total
+
4893 latest_sample
.channel_total_consumed
;
4896 channel_info
->session_info
->consumed_data_size
=
4897 latest_session_consumed_total
;
4899 /* Find triggers associated with this channel. */
4900 cds_lfht_lookup(state
->channel_triggers_ht
,
4901 hash_channel_key(&latest_sample
.key
),
4902 match_channel_trigger_list
,
4905 node
= cds_lfht_iter_get_node(&iter
);
4906 if (caa_likely(!node
)) {
4910 channel_creds
= (typeof(channel_creds
)) {
4911 .uid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->uid
),
4912 .gid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->gid
),
4915 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
4916 channel_triggers_ht_node
);
4917 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
4919 const struct lttng_condition
*condition
;
4920 struct lttng_trigger
*trigger
;
4921 struct notification_client_list
*client_list
= NULL
;
4922 struct lttng_evaluation
*evaluation
= NULL
;
4923 enum action_executor_status executor_status
;
4926 trigger
= trigger_list_element
->trigger
;
4927 condition
= lttng_trigger_get_const_condition(trigger
);
4928 LTTNG_ASSERT(condition
);
4931 * Check if any client is subscribed to the result of this
4934 client_list
= get_client_list_from_condition(state
, condition
);
4936 ret
= evaluate_buffer_condition(condition
, &evaluation
, state
,
4937 previous_sample_available
? &previous_sample
: NULL
,
4939 previous_session_consumed_total
,
4940 latest_session_consumed_total
,
4942 if (caa_unlikely(ret
)) {
4946 if (caa_likely(!evaluation
)) {
4951 * Ownership of `evaluation` transferred to the action executor
4952 * no matter the result.
4954 executor_status
= action_executor_enqueue_trigger(
4955 state
->executor
, trigger
, evaluation
,
4956 &channel_creds
, client_list
);
4958 switch (executor_status
) {
4959 case ACTION_EXECUTOR_STATUS_OK
:
4961 case ACTION_EXECUTOR_STATUS_ERROR
:
4962 case ACTION_EXECUTOR_STATUS_INVALID
:
4964 * TODO Add trigger identification (name/id) when
4965 * it is added to the API.
4967 ERR("Fatal error occurred while enqueuing action associated with buffer-condition trigger");
4970 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4972 * TODO Add trigger identification (name/id) when
4973 * it is added to the API.
4975 * Not a fatal error.
4977 WARN("No space left when enqueuing action associated with buffer-condition trigger");
4985 notification_client_list_put(client_list
);
4986 if (caa_unlikely(ret
)) {