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/group-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/on-event-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>
43 #include "condition-internal.h"
44 #include "event-notifier-error-accounting.h"
45 #include "notification-thread.h"
46 #include "notification-thread-events.h"
47 #include "notification-thread-commands.h"
48 #include "lttng-sessiond.h"
51 #define CLIENT_POLL_MASK_IN (LPOLLIN | LPOLLERR | LPOLLHUP | LPOLLRDHUP)
52 #define CLIENT_POLL_MASK_IN_OUT (CLIENT_POLL_MASK_IN | LPOLLOUT)
54 /* The tracers currently limit the capture size to PIPE_BUF (4kb on linux). */
55 #define MAX_CAPTURE_SIZE (PIPE_BUF)
57 enum lttng_object_type
{
58 LTTNG_OBJECT_TYPE_UNKNOWN
,
59 LTTNG_OBJECT_TYPE_NONE
,
60 LTTNG_OBJECT_TYPE_CHANNEL
,
61 LTTNG_OBJECT_TYPE_SESSION
,
64 struct lttng_trigger_list_element
{
65 /* No ownership of the trigger object is assumed. */
66 struct lttng_trigger
*trigger
;
67 struct cds_list_head node
;
70 struct lttng_channel_trigger_list
{
71 struct channel_key channel_key
;
72 /* List of struct lttng_trigger_list_element. */
73 struct cds_list_head list
;
74 /* Node in the channel_triggers_ht */
75 struct cds_lfht_node channel_triggers_ht_node
;
76 /* call_rcu delayed reclaim. */
77 struct rcu_head rcu_node
;
81 * List of triggers applying to a given session.
84 * - lttng_session_trigger_list_create()
85 * - lttng_session_trigger_list_build()
86 * - lttng_session_trigger_list_destroy()
87 * - lttng_session_trigger_list_add()
89 struct lttng_session_trigger_list
{
91 * Not owned by this; points to the session_info structure's
94 const char *session_name
;
95 /* List of struct lttng_trigger_list_element. */
96 struct cds_list_head list
;
97 /* Node in the session_triggers_ht */
98 struct cds_lfht_node session_triggers_ht_node
;
100 * Weak reference to the notification system's session triggers
103 * The session trigger list structure structure is owned by
104 * the session's session_info.
106 * The session_info is kept alive the the channel_infos holding a
107 * reference to it (reference counting). When those channels are
108 * destroyed (at runtime or on teardown), the reference they hold
109 * to the session_info are released. On destruction of session_info,
110 * session_info_destroy() will remove the list of triggers applying
111 * to this session from the notification system's state.
113 * This implies that the session_triggers_ht must be destroyed
114 * after the channels.
116 struct cds_lfht
*session_triggers_ht
;
117 /* Used for delayed RCU reclaim. */
118 struct rcu_head rcu_node
;
121 struct lttng_trigger_ht_element
{
122 struct lttng_trigger
*trigger
;
123 struct cds_lfht_node node
;
124 struct cds_lfht_node node_by_name_uid
;
125 /* call_rcu delayed reclaim. */
126 struct rcu_head rcu_node
;
129 struct lttng_condition_list_element
{
130 struct lttng_condition
*condition
;
131 struct cds_list_head node
;
134 struct channel_state_sample
{
135 struct channel_key key
;
136 struct cds_lfht_node channel_state_ht_node
;
137 uint64_t highest_usage
;
138 uint64_t lowest_usage
;
139 uint64_t channel_total_consumed
;
140 /* call_rcu delayed reclaim. */
141 struct rcu_head rcu_node
;
144 static unsigned long hash_channel_key(struct channel_key
*key
);
145 static int evaluate_buffer_condition(const struct lttng_condition
*condition
,
146 struct lttng_evaluation
**evaluation
,
147 const struct notification_thread_state
*state
,
148 const struct channel_state_sample
*previous_sample
,
149 const struct channel_state_sample
*latest_sample
,
150 uint64_t previous_session_consumed_total
,
151 uint64_t latest_session_consumed_total
,
152 struct channel_info
*channel_info
);
154 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
155 const struct lttng_evaluation
*evaluation
,
156 struct notification_client_list
*client_list
,
157 struct notification_thread_state
*state
,
158 uid_t channel_uid
, gid_t channel_gid
);
161 /* session_info API */
163 void session_info_destroy(void *_data
);
165 void session_info_get(struct session_info
*session_info
);
167 void session_info_put(struct session_info
*session_info
);
169 struct session_info
*session_info_create(const char *name
,
170 uid_t uid
, gid_t gid
,
171 struct lttng_session_trigger_list
*trigger_list
,
172 struct cds_lfht
*sessions_ht
);
174 void session_info_add_channel(struct session_info
*session_info
,
175 struct channel_info
*channel_info
);
177 void session_info_remove_channel(struct session_info
*session_info
,
178 struct channel_info
*channel_info
);
180 /* lttng_session_trigger_list API */
182 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
183 const char *session_name
,
184 struct cds_lfht
*session_triggers_ht
);
186 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
187 const struct notification_thread_state
*state
,
188 const char *session_name
);
190 void lttng_session_trigger_list_destroy(
191 struct lttng_session_trigger_list
*list
);
193 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
194 struct lttng_trigger
*trigger
);
197 int client_handle_transmission_status(
198 struct notification_client
*client
,
199 enum client_transmission_status transmission_status
,
200 struct notification_thread_state
*state
);
203 int handle_one_event_notifier_notification(
204 struct notification_thread_state
*state
,
205 int pipe
, enum lttng_domain_type domain
);
208 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
);
211 int match_client_socket(struct cds_lfht_node
*node
, const void *key
)
213 /* This double-cast is intended to supress pointer-to-cast warning. */
214 const int socket
= (int) (intptr_t) key
;
215 const struct notification_client
*client
= caa_container_of(node
,
216 struct notification_client
, client_socket_ht_node
);
218 return client
->socket
== socket
;
222 int match_client_id(struct cds_lfht_node
*node
, const void *key
)
224 /* This double-cast is intended to supress pointer-to-cast warning. */
225 const notification_client_id id
= *((notification_client_id
*) key
);
226 const struct notification_client
*client
= caa_container_of(
227 node
, struct notification_client
, client_id_ht_node
);
229 return client
->id
== id
;
233 int match_channel_trigger_list(struct cds_lfht_node
*node
, const void *key
)
235 struct channel_key
*channel_key
= (struct channel_key
*) key
;
236 struct lttng_channel_trigger_list
*trigger_list
;
238 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
239 channel_triggers_ht_node
);
241 return !!((channel_key
->key
== trigger_list
->channel_key
.key
) &&
242 (channel_key
->domain
== trigger_list
->channel_key
.domain
));
246 int match_session_trigger_list(struct cds_lfht_node
*node
, const void *key
)
248 const char *session_name
= (const char *) key
;
249 struct lttng_session_trigger_list
*trigger_list
;
251 trigger_list
= caa_container_of(node
, struct lttng_session_trigger_list
,
252 session_triggers_ht_node
);
254 return !!(strcmp(trigger_list
->session_name
, session_name
) == 0);
258 int match_channel_state_sample(struct cds_lfht_node
*node
, const void *key
)
260 struct channel_key
*channel_key
= (struct channel_key
*) key
;
261 struct channel_state_sample
*sample
;
263 sample
= caa_container_of(node
, struct channel_state_sample
,
264 channel_state_ht_node
);
266 return !!((channel_key
->key
== sample
->key
.key
) &&
267 (channel_key
->domain
== sample
->key
.domain
));
271 int match_channel_info(struct cds_lfht_node
*node
, const void *key
)
273 struct channel_key
*channel_key
= (struct channel_key
*) key
;
274 struct channel_info
*channel_info
;
276 channel_info
= caa_container_of(node
, struct channel_info
,
279 return !!((channel_key
->key
== channel_info
->key
.key
) &&
280 (channel_key
->domain
== channel_info
->key
.domain
));
284 int match_trigger(struct cds_lfht_node
*node
, const void *key
)
286 struct lttng_trigger
*trigger_key
= (struct lttng_trigger
*) key
;
287 struct lttng_trigger_ht_element
*trigger_ht_element
;
289 trigger_ht_element
= caa_container_of(node
, struct lttng_trigger_ht_element
,
292 return !!lttng_trigger_is_equal(trigger_key
, trigger_ht_element
->trigger
);
296 int match_trigger_token(struct cds_lfht_node
*node
, const void *key
)
298 const uint64_t *_key
= key
;
299 struct notification_trigger_tokens_ht_element
*element
;
301 element
= caa_container_of(node
,
302 struct notification_trigger_tokens_ht_element
, node
);
303 return *_key
== element
->token
;
307 int match_client_list_condition(struct cds_lfht_node
*node
, const void *key
)
309 struct lttng_condition
*condition_key
= (struct lttng_condition
*) key
;
310 struct notification_client_list
*client_list
;
311 const struct lttng_condition
*condition
;
313 assert(condition_key
);
315 client_list
= caa_container_of(node
, struct notification_client_list
,
316 notification_trigger_clients_ht_node
);
317 condition
= lttng_trigger_get_const_condition(client_list
->trigger
);
319 return !!lttng_condition_is_equal(condition_key
, condition
);
323 int match_session(struct cds_lfht_node
*node
, const void *key
)
325 const char *name
= key
;
326 struct session_info
*session_info
= caa_container_of(
327 node
, struct session_info
, sessions_ht_node
);
329 return !strcmp(session_info
->name
, name
);
333 const char *notification_command_type_str(
334 enum notification_thread_command_type type
)
337 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
338 return "REGISTER_TRIGGER";
339 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
340 return "UNREGISTER_TRIGGER";
341 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
342 return "ADD_CHANNEL";
343 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
344 return "REMOVE_CHANNEL";
345 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
346 return "SESSION_ROTATION_ONGOING";
347 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
348 return "SESSION_ROTATION_COMPLETED";
349 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
350 return "ADD_TRACER_EVENT_SOURCE";
351 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
352 return "REMOVE_TRACER_EVENT_SOURCE";
353 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
354 return "LIST_TRIGGERS";
355 case NOTIFICATION_COMMAND_TYPE_QUIT
:
357 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
358 return "CLIENT_COMMUNICATION_UPDATE";
365 * Match trigger based on name and credentials only.
366 * Name duplication is NOT allowed for the same uid.
369 int match_trigger_by_name_uid(struct cds_lfht_node
*node
,
374 const char *key_name
;
375 enum lttng_trigger_status status
;
376 const struct lttng_credentials
*key_creds
;
377 const struct lttng_credentials
*node_creds
;
378 const struct lttng_trigger
*trigger_key
=
379 (const struct lttng_trigger
*) key
;
380 const struct lttng_trigger_ht_element
*trigger_ht_element
=
381 caa_container_of(node
,
382 struct lttng_trigger_ht_element
,
385 status
= lttng_trigger_get_name(trigger_ht_element
->trigger
, &name
);
386 assert(status
== LTTNG_TRIGGER_STATUS_OK
);
388 status
= lttng_trigger_get_name(trigger_key
, &key_name
);
389 assert(status
== LTTNG_TRIGGER_STATUS_OK
);
391 /* Compare the names. */
392 if (strcmp(name
, key_name
) != 0) {
396 /* Compare the owners' UIDs. */
397 key_creds
= lttng_trigger_get_credentials(trigger_key
);
398 node_creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
400 match
= lttng_credentials_is_equal_uid(key_creds
, node_creds
);
407 * Hash trigger based on name and credentials only.
410 unsigned long hash_trigger_by_name_uid(const struct lttng_trigger
*trigger
)
412 unsigned long hash
= 0;
413 const struct lttng_credentials
*trigger_creds
;
414 const char *trigger_name
;
415 enum lttng_trigger_status status
;
417 status
= lttng_trigger_get_name(trigger
, &trigger_name
);
418 if (status
== LTTNG_TRIGGER_STATUS_OK
) {
419 hash
= hash_key_str(trigger_name
, lttng_ht_seed
);
422 trigger_creds
= lttng_trigger_get_credentials(trigger
);
423 hash
^= hash_key_ulong((void *) (unsigned long) LTTNG_OPTIONAL_GET(trigger_creds
->uid
),
430 unsigned long hash_channel_key(struct channel_key
*key
)
432 unsigned long key_hash
= hash_key_u64(&key
->key
, lttng_ht_seed
);
433 unsigned long domain_hash
= hash_key_ulong(
434 (void *) (unsigned long) key
->domain
, lttng_ht_seed
);
436 return key_hash
^ domain_hash
;
440 unsigned long hash_client_socket(int socket
)
442 return hash_key_ulong((void *) (unsigned long) socket
, lttng_ht_seed
);
446 unsigned long hash_client_id(notification_client_id id
)
448 return hash_key_u64(&id
, lttng_ht_seed
);
452 * Get the type of object to which a given condition applies. Bindings let
453 * the notification system evaluate a trigger's condition when a given
454 * object's state is updated.
456 * For instance, a condition bound to a channel will be evaluated everytime
457 * the channel's state is changed by a channel monitoring sample.
460 enum lttng_object_type
get_condition_binding_object(
461 const struct lttng_condition
*condition
)
463 switch (lttng_condition_get_type(condition
)) {
464 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
465 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
466 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
467 return LTTNG_OBJECT_TYPE_CHANNEL
;
468 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
469 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
470 return LTTNG_OBJECT_TYPE_SESSION
;
471 case LTTNG_CONDITION_TYPE_ON_EVENT
:
472 return LTTNG_OBJECT_TYPE_NONE
;
474 return LTTNG_OBJECT_TYPE_UNKNOWN
;
479 void free_channel_info_rcu(struct rcu_head
*node
)
481 free(caa_container_of(node
, struct channel_info
, rcu_node
));
485 void channel_info_destroy(struct channel_info
*channel_info
)
491 if (channel_info
->session_info
) {
492 session_info_remove_channel(channel_info
->session_info
,
494 session_info_put(channel_info
->session_info
);
496 if (channel_info
->name
) {
497 free(channel_info
->name
);
499 call_rcu(&channel_info
->rcu_node
, free_channel_info_rcu
);
503 void free_session_info_rcu(struct rcu_head
*node
)
505 free(caa_container_of(node
, struct session_info
, rcu_node
));
508 /* Don't call directly, use the ref-counting mechanism. */
510 void session_info_destroy(void *_data
)
512 struct session_info
*session_info
= _data
;
515 assert(session_info
);
516 if (session_info
->channel_infos_ht
) {
517 ret
= cds_lfht_destroy(session_info
->channel_infos_ht
, NULL
);
519 ERR("[notification-thread] Failed to destroy channel information hash table");
522 lttng_session_trigger_list_destroy(session_info
->trigger_list
);
525 cds_lfht_del(session_info
->sessions_ht
,
526 &session_info
->sessions_ht_node
);
528 free(session_info
->name
);
529 call_rcu(&session_info
->rcu_node
, free_session_info_rcu
);
533 void session_info_get(struct session_info
*session_info
)
538 lttng_ref_get(&session_info
->ref
);
542 void session_info_put(struct session_info
*session_info
)
547 lttng_ref_put(&session_info
->ref
);
551 struct session_info
*session_info_create(const char *name
, uid_t uid
, gid_t gid
,
552 struct lttng_session_trigger_list
*trigger_list
,
553 struct cds_lfht
*sessions_ht
)
555 struct session_info
*session_info
;
559 session_info
= zmalloc(sizeof(*session_info
));
563 lttng_ref_init(&session_info
->ref
, session_info_destroy
);
565 session_info
->channel_infos_ht
= cds_lfht_new(DEFAULT_HT_SIZE
,
566 1, 0, CDS_LFHT_AUTO_RESIZE
| CDS_LFHT_ACCOUNTING
, NULL
);
567 if (!session_info
->channel_infos_ht
) {
571 cds_lfht_node_init(&session_info
->sessions_ht_node
);
572 session_info
->name
= strdup(name
);
573 if (!session_info
->name
) {
576 session_info
->uid
= uid
;
577 session_info
->gid
= gid
;
578 session_info
->trigger_list
= trigger_list
;
579 session_info
->sessions_ht
= sessions_ht
;
583 session_info_put(session_info
);
588 void session_info_add_channel(struct session_info
*session_info
,
589 struct channel_info
*channel_info
)
592 cds_lfht_add(session_info
->channel_infos_ht
,
593 hash_channel_key(&channel_info
->key
),
594 &channel_info
->session_info_channels_ht_node
);
599 void session_info_remove_channel(struct session_info
*session_info
,
600 struct channel_info
*channel_info
)
603 cds_lfht_del(session_info
->channel_infos_ht
,
604 &channel_info
->session_info_channels_ht_node
);
609 struct channel_info
*channel_info_create(const char *channel_name
,
610 struct channel_key
*channel_key
, uint64_t channel_capacity
,
611 struct session_info
*session_info
)
613 struct channel_info
*channel_info
= zmalloc(sizeof(*channel_info
));
619 cds_lfht_node_init(&channel_info
->channels_ht_node
);
620 cds_lfht_node_init(&channel_info
->session_info_channels_ht_node
);
621 memcpy(&channel_info
->key
, channel_key
, sizeof(*channel_key
));
622 channel_info
->capacity
= channel_capacity
;
624 channel_info
->name
= strdup(channel_name
);
625 if (!channel_info
->name
) {
630 * Set the references between session and channel infos:
631 * - channel_info holds a strong reference to session_info
632 * - session_info holds a weak reference to channel_info
634 session_info_get(session_info
);
635 session_info_add_channel(session_info
, channel_info
);
636 channel_info
->session_info
= session_info
;
640 channel_info_destroy(channel_info
);
645 bool notification_client_list_get(struct notification_client_list
*list
)
647 return urcu_ref_get_unless_zero(&list
->ref
);
651 void free_notification_client_list_rcu(struct rcu_head
*node
)
653 free(caa_container_of(node
, struct notification_client_list
,
658 void notification_client_list_release(struct urcu_ref
*list_ref
)
660 struct notification_client_list
*list
=
661 container_of(list_ref
, typeof(*list
), ref
);
662 struct notification_client_list_element
*client_list_element
, *tmp
;
664 if (list
->notification_trigger_clients_ht
) {
666 cds_lfht_del(list
->notification_trigger_clients_ht
,
667 &list
->notification_trigger_clients_ht_node
);
669 list
->notification_trigger_clients_ht
= NULL
;
671 cds_list_for_each_entry_safe(client_list_element
, tmp
,
673 free(client_list_element
);
675 pthread_mutex_destroy(&list
->lock
);
676 call_rcu(&list
->rcu_node
, free_notification_client_list_rcu
);
680 struct notification_client_list
*notification_client_list_create(
681 const struct lttng_trigger
*trigger
)
683 struct notification_client_list
*client_list
=
684 zmalloc(sizeof(*client_list
));
689 pthread_mutex_init(&client_list
->lock
, NULL
);
690 urcu_ref_init(&client_list
->ref
);
691 cds_lfht_node_init(&client_list
->notification_trigger_clients_ht_node
);
692 CDS_INIT_LIST_HEAD(&client_list
->list
);
693 client_list
->trigger
= trigger
;
699 void publish_notification_client_list(
700 struct notification_thread_state
*state
,
701 struct notification_client_list
*list
)
703 const struct lttng_condition
*condition
=
704 lttng_trigger_get_const_condition(list
->trigger
);
706 assert(!list
->notification_trigger_clients_ht
);
707 notification_client_list_get(list
);
709 list
->notification_trigger_clients_ht
=
710 state
->notification_trigger_clients_ht
;
713 cds_lfht_add(state
->notification_trigger_clients_ht
,
714 lttng_condition_hash(condition
),
715 &list
->notification_trigger_clients_ht_node
);
720 void notification_client_list_put(struct notification_client_list
*list
)
725 return urcu_ref_put(&list
->ref
, notification_client_list_release
);
728 /* Provides a reference to the returned list. */
730 struct notification_client_list
*get_client_list_from_condition(
731 struct notification_thread_state
*state
,
732 const struct lttng_condition
*condition
)
734 struct cds_lfht_node
*node
;
735 struct cds_lfht_iter iter
;
736 struct notification_client_list
*list
= NULL
;
739 cds_lfht_lookup(state
->notification_trigger_clients_ht
,
740 lttng_condition_hash(condition
),
741 match_client_list_condition
,
744 node
= cds_lfht_iter_get_node(&iter
);
746 list
= container_of(node
, struct notification_client_list
,
747 notification_trigger_clients_ht_node
);
748 list
= notification_client_list_get(list
) ? list
: NULL
;
756 int evaluate_channel_condition_for_client(
757 const struct lttng_condition
*condition
,
758 struct notification_thread_state
*state
,
759 struct lttng_evaluation
**evaluation
,
760 uid_t
*session_uid
, gid_t
*session_gid
)
763 struct cds_lfht_iter iter
;
764 struct cds_lfht_node
*node
;
765 struct channel_info
*channel_info
= NULL
;
766 struct channel_key
*channel_key
= NULL
;
767 struct channel_state_sample
*last_sample
= NULL
;
768 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
772 /* Find the channel associated with the condition. */
773 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
,
774 channel_trigger_list
, channel_triggers_ht_node
) {
775 struct lttng_trigger_list_element
*element
;
777 cds_list_for_each_entry(element
, &channel_trigger_list
->list
, node
) {
778 const struct lttng_condition
*current_condition
=
779 lttng_trigger_get_const_condition(
782 assert(current_condition
);
783 if (!lttng_condition_is_equal(condition
,
784 current_condition
)) {
788 /* Found the trigger, save the channel key. */
789 channel_key
= &channel_trigger_list
->channel_key
;
793 /* The channel key was found stop iteration. */
799 /* No channel found; normal exit. */
800 DBG("[notification-thread] No known channel associated with newly subscribed-to condition");
805 /* Fetch channel info for the matching channel. */
806 cds_lfht_lookup(state
->channels_ht
,
807 hash_channel_key(channel_key
),
811 node
= cds_lfht_iter_get_node(&iter
);
813 channel_info
= caa_container_of(node
, struct channel_info
,
816 /* Retrieve the channel's last sample, if it exists. */
817 cds_lfht_lookup(state
->channel_state_ht
,
818 hash_channel_key(channel_key
),
819 match_channel_state_sample
,
822 node
= cds_lfht_iter_get_node(&iter
);
824 last_sample
= caa_container_of(node
,
825 struct channel_state_sample
,
826 channel_state_ht_node
);
828 /* Nothing to evaluate, no sample was ever taken. Normal exit */
829 DBG("[notification-thread] No channel sample associated with newly subscribed-to condition");
834 ret
= evaluate_buffer_condition(condition
, evaluation
, state
,
836 0, channel_info
->session_info
->consumed_data_size
,
839 WARN("[notification-thread] Fatal error occurred while evaluating a newly subscribed-to condition");
843 *session_uid
= channel_info
->session_info
->uid
;
844 *session_gid
= channel_info
->session_info
->gid
;
851 const char *get_condition_session_name(const struct lttng_condition
*condition
)
853 const char *session_name
= NULL
;
854 enum lttng_condition_status status
;
856 switch (lttng_condition_get_type(condition
)) {
857 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
858 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
859 status
= lttng_condition_buffer_usage_get_session_name(
860 condition
, &session_name
);
862 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
863 status
= lttng_condition_session_consumed_size_get_session_name(
864 condition
, &session_name
);
866 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
867 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
868 status
= lttng_condition_session_rotation_get_session_name(
869 condition
, &session_name
);
874 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
875 ERR("[notification-thread] Failed to retrieve session rotation condition's session name");
883 int evaluate_session_condition_for_client(
884 const struct lttng_condition
*condition
,
885 struct notification_thread_state
*state
,
886 struct lttng_evaluation
**evaluation
,
887 uid_t
*session_uid
, gid_t
*session_gid
)
890 struct cds_lfht_iter iter
;
891 struct cds_lfht_node
*node
;
892 const char *session_name
;
893 struct session_info
*session_info
= NULL
;
896 session_name
= get_condition_session_name(condition
);
898 /* Find the session associated with the trigger. */
899 cds_lfht_lookup(state
->sessions_ht
,
900 hash_key_str(session_name
, lttng_ht_seed
),
904 node
= cds_lfht_iter_get_node(&iter
);
906 DBG("[notification-thread] No known session matching name \"%s\"",
912 session_info
= caa_container_of(node
, struct session_info
,
914 session_info_get(session_info
);
917 * Evaluation is performed in-line here since only one type of
918 * session-bound condition is handled for the moment.
920 switch (lttng_condition_get_type(condition
)) {
921 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
922 if (!session_info
->rotation
.ongoing
) {
924 goto end_session_put
;
927 *evaluation
= lttng_evaluation_session_rotation_ongoing_create(
928 session_info
->rotation
.id
);
931 ERR("[notification-thread] Failed to create session rotation ongoing evaluation for session \"%s\"",
934 goto end_session_put
;
940 goto end_session_put
;
943 *session_uid
= session_info
->uid
;
944 *session_gid
= session_info
->gid
;
947 session_info_put(session_info
);
954 int evaluate_condition_for_client(const struct lttng_trigger
*trigger
,
955 const struct lttng_condition
*condition
,
956 struct notification_client
*client
,
957 struct notification_thread_state
*state
)
960 struct lttng_evaluation
*evaluation
= NULL
;
961 struct notification_client_list client_list
= {
962 .lock
= PTHREAD_MUTEX_INITIALIZER
,
964 struct notification_client_list_element client_list_element
= { 0 };
965 uid_t object_uid
= 0;
966 gid_t object_gid
= 0;
973 switch (get_condition_binding_object(condition
)) {
974 case LTTNG_OBJECT_TYPE_SESSION
:
975 ret
= evaluate_session_condition_for_client(condition
, state
,
976 &evaluation
, &object_uid
, &object_gid
);
978 case LTTNG_OBJECT_TYPE_CHANNEL
:
979 ret
= evaluate_channel_condition_for_client(condition
, state
,
980 &evaluation
, &object_uid
, &object_gid
);
982 case LTTNG_OBJECT_TYPE_NONE
:
983 DBG("[notification-thread] Newly subscribed-to condition not bound to object, nothing to evaluate");
986 case LTTNG_OBJECT_TYPE_UNKNOWN
:
996 /* Evaluation yielded nothing. Normal exit. */
997 DBG("[notification-thread] Newly subscribed-to condition evaluated to false, nothing to report to client");
1003 * Create a temporary client list with the client currently
1006 cds_lfht_node_init(&client_list
.notification_trigger_clients_ht_node
);
1007 CDS_INIT_LIST_HEAD(&client_list
.list
);
1008 client_list
.trigger
= trigger
;
1010 CDS_INIT_LIST_HEAD(&client_list_element
.node
);
1011 client_list_element
.client
= client
;
1012 cds_list_add(&client_list_element
.node
, &client_list
.list
);
1014 /* Send evaluation result to the newly-subscribed client. */
1015 DBG("[notification-thread] Newly subscribed-to condition evaluated to true, notifying client");
1016 ret
= send_evaluation_to_clients(trigger
, evaluation
, &client_list
,
1017 state
, object_uid
, object_gid
);
1024 int notification_thread_client_subscribe(struct notification_client
*client
,
1025 struct lttng_condition
*condition
,
1026 struct notification_thread_state
*state
,
1027 enum lttng_notification_channel_status
*_status
)
1030 struct notification_client_list
*client_list
= NULL
;
1031 struct lttng_condition_list_element
*condition_list_element
= NULL
;
1032 struct notification_client_list_element
*client_list_element
= NULL
;
1033 enum lttng_notification_channel_status status
=
1034 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1037 * Ensure that the client has not already subscribed to this condition
1040 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
, node
) {
1041 if (lttng_condition_is_equal(condition_list_element
->condition
,
1043 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_ALREADY_SUBSCRIBED
;
1048 condition_list_element
= zmalloc(sizeof(*condition_list_element
));
1049 if (!condition_list_element
) {
1053 client_list_element
= zmalloc(sizeof(*client_list_element
));
1054 if (!client_list_element
) {
1060 * Add the newly-subscribed condition to the client's subscription list.
1062 CDS_INIT_LIST_HEAD(&condition_list_element
->node
);
1063 condition_list_element
->condition
= condition
;
1064 cds_list_add(&condition_list_element
->node
, &client
->condition_list
);
1066 client_list
= get_client_list_from_condition(state
, condition
);
1069 * No notification-emiting trigger registered with this
1070 * condition. We don't evaluate the condition right away
1071 * since this trigger is not registered yet.
1073 free(client_list_element
);
1078 * The condition to which the client just subscribed is evaluated
1079 * at this point so that conditions that are already TRUE result
1080 * in a notification being sent out.
1082 * The client_list's trigger is used without locking the list itself.
1083 * This is correct since the list doesn't own the trigger and the
1084 * object is immutable.
1086 if (evaluate_condition_for_client(client_list
->trigger
, condition
,
1088 WARN("[notification-thread] Evaluation of a condition on client subscription failed, aborting.");
1090 free(client_list_element
);
1095 * Add the client to the list of clients interested in a given trigger
1096 * if a "notification" trigger with a corresponding condition was
1099 client_list_element
->client
= client
;
1100 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
1102 pthread_mutex_lock(&client_list
->lock
);
1103 cds_list_add(&client_list_element
->node
, &client_list
->list
);
1104 pthread_mutex_unlock(&client_list
->lock
);
1110 notification_client_list_put(client_list
);
1114 free(condition_list_element
);
1115 free(client_list_element
);
1120 int notification_thread_client_unsubscribe(
1121 struct notification_client
*client
,
1122 struct lttng_condition
*condition
,
1123 struct notification_thread_state
*state
,
1124 enum lttng_notification_channel_status
*_status
)
1126 struct notification_client_list
*client_list
;
1127 struct lttng_condition_list_element
*condition_list_element
,
1129 struct notification_client_list_element
*client_list_element
,
1131 bool condition_found
= false;
1132 enum lttng_notification_channel_status status
=
1133 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1135 /* Remove the condition from the client's condition list. */
1136 cds_list_for_each_entry_safe(condition_list_element
, condition_tmp
,
1137 &client
->condition_list
, node
) {
1138 if (!lttng_condition_is_equal(condition_list_element
->condition
,
1143 cds_list_del(&condition_list_element
->node
);
1145 * The caller may be iterating on the client's conditions to
1146 * tear down a client's connection. In this case, the condition
1147 * will be destroyed at the end.
1149 if (condition
!= condition_list_element
->condition
) {
1150 lttng_condition_destroy(
1151 condition_list_element
->condition
);
1153 free(condition_list_element
);
1154 condition_found
= true;
1158 if (!condition_found
) {
1159 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNKNOWN_CONDITION
;
1164 * Remove the client from the list of clients interested the trigger
1165 * matching the condition.
1167 client_list
= get_client_list_from_condition(state
, condition
);
1172 pthread_mutex_lock(&client_list
->lock
);
1173 cds_list_for_each_entry_safe(client_list_element
, client_tmp
,
1174 &client_list
->list
, node
) {
1175 if (client_list_element
->client
->id
!= client
->id
) {
1178 cds_list_del(&client_list_element
->node
);
1179 free(client_list_element
);
1182 pthread_mutex_unlock(&client_list
->lock
);
1183 notification_client_list_put(client_list
);
1186 lttng_condition_destroy(condition
);
1194 void free_notification_client_rcu(struct rcu_head
*node
)
1196 free(caa_container_of(node
, struct notification_client
, rcu_node
));
1200 void notification_client_destroy(struct notification_client
*client
,
1201 struct notification_thread_state
*state
)
1208 * The client object is not reachable by other threads, no need to lock
1211 if (client
->socket
>= 0) {
1212 (void) lttcomm_close_unix_sock(client
->socket
);
1213 client
->socket
= -1;
1215 client
->communication
.active
= false;
1216 lttng_payload_reset(&client
->communication
.inbound
.payload
);
1217 lttng_payload_reset(&client
->communication
.outbound
.payload
);
1218 pthread_mutex_destroy(&client
->lock
);
1219 call_rcu(&client
->rcu_node
, free_notification_client_rcu
);
1223 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1227 struct notification_client
*get_client_from_socket(int socket
,
1228 struct notification_thread_state
*state
)
1230 struct cds_lfht_iter iter
;
1231 struct cds_lfht_node
*node
;
1232 struct notification_client
*client
= NULL
;
1234 cds_lfht_lookup(state
->client_socket_ht
,
1235 hash_client_socket(socket
),
1236 match_client_socket
,
1237 (void *) (unsigned long) socket
,
1239 node
= cds_lfht_iter_get_node(&iter
);
1244 client
= caa_container_of(node
, struct notification_client
,
1245 client_socket_ht_node
);
1251 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1255 struct notification_client
*get_client_from_id(notification_client_id id
,
1256 struct notification_thread_state
*state
)
1258 struct cds_lfht_iter iter
;
1259 struct cds_lfht_node
*node
;
1260 struct notification_client
*client
= NULL
;
1262 cds_lfht_lookup(state
->client_id_ht
,
1267 node
= cds_lfht_iter_get_node(&iter
);
1272 client
= caa_container_of(node
, struct notification_client
,
1279 bool buffer_usage_condition_applies_to_channel(
1280 const struct lttng_condition
*condition
,
1281 const struct channel_info
*channel_info
)
1283 enum lttng_condition_status status
;
1284 enum lttng_domain_type condition_domain
;
1285 const char *condition_session_name
= NULL
;
1286 const char *condition_channel_name
= NULL
;
1288 status
= lttng_condition_buffer_usage_get_domain_type(condition
,
1290 assert(status
== LTTNG_CONDITION_STATUS_OK
);
1291 if (channel_info
->key
.domain
!= condition_domain
) {
1295 status
= lttng_condition_buffer_usage_get_session_name(
1296 condition
, &condition_session_name
);
1297 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1299 status
= lttng_condition_buffer_usage_get_channel_name(
1300 condition
, &condition_channel_name
);
1301 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_channel_name
);
1303 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1306 if (strcmp(channel_info
->name
, condition_channel_name
)) {
1316 bool session_consumed_size_condition_applies_to_channel(
1317 const struct lttng_condition
*condition
,
1318 const struct channel_info
*channel_info
)
1320 enum lttng_condition_status status
;
1321 const char *condition_session_name
= NULL
;
1323 status
= lttng_condition_session_consumed_size_get_session_name(
1324 condition
, &condition_session_name
);
1325 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1327 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1337 bool trigger_applies_to_channel(const struct lttng_trigger
*trigger
,
1338 const struct channel_info
*channel_info
)
1340 const struct lttng_condition
*condition
;
1341 bool trigger_applies
;
1343 condition
= lttng_trigger_get_const_condition(trigger
);
1348 switch (lttng_condition_get_type(condition
)) {
1349 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
1350 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
1351 trigger_applies
= buffer_usage_condition_applies_to_channel(
1352 condition
, channel_info
);
1354 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
1355 trigger_applies
= session_consumed_size_condition_applies_to_channel(
1356 condition
, channel_info
);
1362 return trigger_applies
;
1368 bool trigger_applies_to_client(struct lttng_trigger
*trigger
,
1369 struct notification_client
*client
)
1371 bool applies
= false;
1372 struct lttng_condition_list_element
*condition_list_element
;
1374 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
,
1376 applies
= lttng_condition_is_equal(
1377 condition_list_element
->condition
,
1378 lttng_trigger_get_condition(trigger
));
1386 /* Must be called with RCU read lock held. */
1388 struct lttng_session_trigger_list
*get_session_trigger_list(
1389 struct notification_thread_state
*state
,
1390 const char *session_name
)
1392 struct lttng_session_trigger_list
*list
= NULL
;
1393 struct cds_lfht_node
*node
;
1394 struct cds_lfht_iter iter
;
1396 cds_lfht_lookup(state
->session_triggers_ht
,
1397 hash_key_str(session_name
, lttng_ht_seed
),
1398 match_session_trigger_list
,
1401 node
= cds_lfht_iter_get_node(&iter
);
1404 * Not an error, the list of triggers applying to that session
1405 * will be initialized when the session is created.
1407 DBG("[notification-thread] No trigger list found for session \"%s\" as it is not yet known to the notification system",
1412 list
= caa_container_of(node
,
1413 struct lttng_session_trigger_list
,
1414 session_triggers_ht_node
);
1420 * Allocate an empty lttng_session_trigger_list for the session named
1423 * No ownership of 'session_name' is assumed by the session trigger list.
1424 * It is the caller's responsability to ensure the session name is alive
1425 * for as long as this list is.
1428 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
1429 const char *session_name
,
1430 struct cds_lfht
*session_triggers_ht
)
1432 struct lttng_session_trigger_list
*list
;
1434 list
= zmalloc(sizeof(*list
));
1438 list
->session_name
= session_name
;
1439 CDS_INIT_LIST_HEAD(&list
->list
);
1440 cds_lfht_node_init(&list
->session_triggers_ht_node
);
1441 list
->session_triggers_ht
= session_triggers_ht
;
1444 /* Publish the list through the session_triggers_ht. */
1445 cds_lfht_add(session_triggers_ht
,
1446 hash_key_str(session_name
, lttng_ht_seed
),
1447 &list
->session_triggers_ht_node
);
1454 void free_session_trigger_list_rcu(struct rcu_head
*node
)
1456 free(caa_container_of(node
, struct lttng_session_trigger_list
,
1461 void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list
*list
)
1463 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1465 /* Empty the list element by element, and then free the list itself. */
1466 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1467 &list
->list
, node
) {
1468 cds_list_del(&trigger_list_element
->node
);
1469 free(trigger_list_element
);
1472 /* Unpublish the list from the session_triggers_ht. */
1473 cds_lfht_del(list
->session_triggers_ht
,
1474 &list
->session_triggers_ht_node
);
1476 call_rcu(&list
->rcu_node
, free_session_trigger_list_rcu
);
1480 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
1481 struct lttng_trigger
*trigger
)
1484 struct lttng_trigger_list_element
*new_element
=
1485 zmalloc(sizeof(*new_element
));
1491 CDS_INIT_LIST_HEAD(&new_element
->node
);
1492 new_element
->trigger
= trigger
;
1493 cds_list_add(&new_element
->node
, &list
->list
);
1499 bool trigger_applies_to_session(const struct lttng_trigger
*trigger
,
1500 const char *session_name
)
1502 bool applies
= false;
1503 const struct lttng_condition
*condition
;
1505 condition
= lttng_trigger_get_const_condition(trigger
);
1506 switch (lttng_condition_get_type(condition
)) {
1507 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1508 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1510 enum lttng_condition_status condition_status
;
1511 const char *condition_session_name
;
1513 condition_status
= lttng_condition_session_rotation_get_session_name(
1514 condition
, &condition_session_name
);
1515 if (condition_status
!= LTTNG_CONDITION_STATUS_OK
) {
1516 ERR("[notification-thread] Failed to retrieve session rotation condition's session name");
1520 assert(condition_session_name
);
1521 applies
= !strcmp(condition_session_name
, session_name
);
1532 * Allocate and initialize an lttng_session_trigger_list which contains
1533 * all triggers that apply to the session named 'session_name'.
1535 * No ownership of 'session_name' is assumed by the session trigger list.
1536 * It is the caller's responsability to ensure the session name is alive
1537 * for as long as this list is.
1540 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
1541 const struct notification_thread_state
*state
,
1542 const char *session_name
)
1544 int trigger_count
= 0;
1545 struct lttng_session_trigger_list
*session_trigger_list
= NULL
;
1546 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1547 struct cds_lfht_iter iter
;
1549 session_trigger_list
= lttng_session_trigger_list_create(session_name
,
1550 state
->session_triggers_ht
);
1552 /* Add all triggers applying to the session named 'session_name'. */
1553 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1557 if (!trigger_applies_to_session(trigger_ht_element
->trigger
,
1562 ret
= lttng_session_trigger_list_add(session_trigger_list
,
1563 trigger_ht_element
->trigger
);
1571 DBG("[notification-thread] Found %i triggers that apply to newly created session",
1573 return session_trigger_list
;
1575 lttng_session_trigger_list_destroy(session_trigger_list
);
1580 struct session_info
*find_or_create_session_info(
1581 struct notification_thread_state
*state
,
1582 const char *name
, uid_t uid
, gid_t gid
)
1584 struct session_info
*session
= NULL
;
1585 struct cds_lfht_node
*node
;
1586 struct cds_lfht_iter iter
;
1587 struct lttng_session_trigger_list
*trigger_list
;
1590 cds_lfht_lookup(state
->sessions_ht
,
1591 hash_key_str(name
, lttng_ht_seed
),
1595 node
= cds_lfht_iter_get_node(&iter
);
1597 DBG("[notification-thread] Found session info of session \"%s\" (uid = %i, gid = %i)",
1599 session
= caa_container_of(node
, struct session_info
,
1601 assert(session
->uid
== uid
);
1602 assert(session
->gid
== gid
);
1603 session_info_get(session
);
1607 trigger_list
= lttng_session_trigger_list_build(state
, name
);
1608 if (!trigger_list
) {
1612 session
= session_info_create(name
, uid
, gid
, trigger_list
,
1613 state
->sessions_ht
);
1615 ERR("[notification-thread] Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
1617 lttng_session_trigger_list_destroy(trigger_list
);
1620 trigger_list
= NULL
;
1622 cds_lfht_add(state
->sessions_ht
, hash_key_str(name
, lttng_ht_seed
),
1623 &session
->sessions_ht_node
);
1629 session_info_put(session
);
1634 int handle_notification_thread_command_add_channel(
1635 struct notification_thread_state
*state
,
1636 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1637 const char *channel_name
, enum lttng_domain_type channel_domain
,
1638 uint64_t channel_key_int
, uint64_t channel_capacity
,
1639 enum lttng_error_code
*cmd_result
)
1641 struct cds_list_head trigger_list
;
1642 struct channel_info
*new_channel_info
= NULL
;
1643 struct channel_key channel_key
= {
1644 .key
= channel_key_int
,
1645 .domain
= channel_domain
,
1647 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
1648 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1649 int trigger_count
= 0;
1650 struct cds_lfht_iter iter
;
1651 struct session_info
*session_info
= NULL
;
1653 DBG("[notification-thread] Adding channel %s from session %s, channel key = %" PRIu64
" in %s domain",
1654 channel_name
, session_name
, channel_key_int
,
1655 lttng_domain_type_str(channel_domain
));
1657 CDS_INIT_LIST_HEAD(&trigger_list
);
1659 session_info
= find_or_create_session_info(state
, session_name
,
1660 session_uid
, session_gid
);
1661 if (!session_info
) {
1662 /* Allocation error or an internal error occurred. */
1666 new_channel_info
= channel_info_create(channel_name
, &channel_key
,
1667 channel_capacity
, session_info
);
1668 if (!new_channel_info
) {
1673 /* Build a list of all triggers applying to the new channel. */
1674 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1676 struct lttng_trigger_list_element
*new_element
;
1678 if (!trigger_applies_to_channel(trigger_ht_element
->trigger
,
1679 new_channel_info
)) {
1683 new_element
= zmalloc(sizeof(*new_element
));
1688 CDS_INIT_LIST_HEAD(&new_element
->node
);
1689 new_element
->trigger
= trigger_ht_element
->trigger
;
1690 cds_list_add(&new_element
->node
, &trigger_list
);
1695 DBG("[notification-thread] Found %i triggers that apply to newly added channel",
1697 channel_trigger_list
= zmalloc(sizeof(*channel_trigger_list
));
1698 if (!channel_trigger_list
) {
1701 channel_trigger_list
->channel_key
= new_channel_info
->key
;
1702 CDS_INIT_LIST_HEAD(&channel_trigger_list
->list
);
1703 cds_lfht_node_init(&channel_trigger_list
->channel_triggers_ht_node
);
1704 cds_list_splice(&trigger_list
, &channel_trigger_list
->list
);
1707 /* Add channel to the channel_ht which owns the channel_infos. */
1708 cds_lfht_add(state
->channels_ht
,
1709 hash_channel_key(&new_channel_info
->key
),
1710 &new_channel_info
->channels_ht_node
);
1712 * Add the list of triggers associated with this channel to the
1713 * channel_triggers_ht.
1715 cds_lfht_add(state
->channel_triggers_ht
,
1716 hash_channel_key(&new_channel_info
->key
),
1717 &channel_trigger_list
->channel_triggers_ht_node
);
1719 session_info_put(session_info
);
1720 *cmd_result
= LTTNG_OK
;
1723 channel_info_destroy(new_channel_info
);
1724 session_info_put(session_info
);
1729 void free_channel_trigger_list_rcu(struct rcu_head
*node
)
1731 free(caa_container_of(node
, struct lttng_channel_trigger_list
,
1736 void free_channel_state_sample_rcu(struct rcu_head
*node
)
1738 free(caa_container_of(node
, struct channel_state_sample
,
1743 int handle_notification_thread_command_remove_channel(
1744 struct notification_thread_state
*state
,
1745 uint64_t channel_key
, enum lttng_domain_type domain
,
1746 enum lttng_error_code
*cmd_result
)
1748 struct cds_lfht_node
*node
;
1749 struct cds_lfht_iter iter
;
1750 struct lttng_channel_trigger_list
*trigger_list
;
1751 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1752 struct channel_key key
= { .key
= channel_key
, .domain
= domain
};
1753 struct channel_info
*channel_info
;
1755 DBG("[notification-thread] Removing channel key = %" PRIu64
" in %s domain",
1756 channel_key
, lttng_domain_type_str(domain
));
1760 cds_lfht_lookup(state
->channel_triggers_ht
,
1761 hash_channel_key(&key
),
1762 match_channel_trigger_list
,
1765 node
= cds_lfht_iter_get_node(&iter
);
1767 * There is a severe internal error if we are being asked to remove a
1768 * channel that doesn't exist.
1771 ERR("[notification-thread] Channel being removed is unknown to the notification thread");
1775 /* Free the list of triggers associated with this channel. */
1776 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
1777 channel_triggers_ht_node
);
1778 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1779 &trigger_list
->list
, node
) {
1780 cds_list_del(&trigger_list_element
->node
);
1781 free(trigger_list_element
);
1783 cds_lfht_del(state
->channel_triggers_ht
, node
);
1784 call_rcu(&trigger_list
->rcu_node
, free_channel_trigger_list_rcu
);
1786 /* Free sampled channel state. */
1787 cds_lfht_lookup(state
->channel_state_ht
,
1788 hash_channel_key(&key
),
1789 match_channel_state_sample
,
1792 node
= cds_lfht_iter_get_node(&iter
);
1794 * This is expected to be NULL if the channel is destroyed before we
1795 * received a sample.
1798 struct channel_state_sample
*sample
= caa_container_of(node
,
1799 struct channel_state_sample
,
1800 channel_state_ht_node
);
1802 cds_lfht_del(state
->channel_state_ht
, node
);
1803 call_rcu(&sample
->rcu_node
, free_channel_state_sample_rcu
);
1806 /* Remove the channel from the channels_ht and free it. */
1807 cds_lfht_lookup(state
->channels_ht
,
1808 hash_channel_key(&key
),
1812 node
= cds_lfht_iter_get_node(&iter
);
1814 channel_info
= caa_container_of(node
, struct channel_info
,
1816 cds_lfht_del(state
->channels_ht
, node
);
1817 channel_info_destroy(channel_info
);
1820 *cmd_result
= LTTNG_OK
;
1825 int handle_notification_thread_command_session_rotation(
1826 struct notification_thread_state
*state
,
1827 enum notification_thread_command_type cmd_type
,
1828 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1829 uint64_t trace_archive_chunk_id
,
1830 struct lttng_trace_archive_location
*location
,
1831 enum lttng_error_code
*_cmd_result
)
1834 enum lttng_error_code cmd_result
= LTTNG_OK
;
1835 struct lttng_session_trigger_list
*trigger_list
;
1836 struct lttng_trigger_list_element
*trigger_list_element
;
1837 struct session_info
*session_info
;
1838 const struct lttng_credentials session_creds
= {
1839 .uid
= LTTNG_OPTIONAL_INIT_VALUE(session_uid
),
1840 .gid
= LTTNG_OPTIONAL_INIT_VALUE(session_gid
),
1845 session_info
= find_or_create_session_info(state
, session_name
,
1846 session_uid
, session_gid
);
1847 if (!session_info
) {
1848 /* Allocation error or an internal error occurred. */
1850 cmd_result
= LTTNG_ERR_NOMEM
;
1854 session_info
->rotation
.ongoing
=
1855 cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
;
1856 session_info
->rotation
.id
= trace_archive_chunk_id
;
1857 trigger_list
= get_session_trigger_list(state
, session_name
);
1858 if (!trigger_list
) {
1859 DBG("[notification-thread] No triggers applying to session \"%s\" found",
1864 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
1866 const struct lttng_condition
*condition
;
1867 struct lttng_trigger
*trigger
;
1868 struct notification_client_list
*client_list
;
1869 struct lttng_evaluation
*evaluation
= NULL
;
1870 enum lttng_condition_type condition_type
;
1871 enum action_executor_status executor_status
;
1873 trigger
= trigger_list_element
->trigger
;
1874 condition
= lttng_trigger_get_const_condition(trigger
);
1876 condition_type
= lttng_condition_get_type(condition
);
1878 if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
&&
1879 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1881 } else if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
&&
1882 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
) {
1886 client_list
= get_client_list_from_condition(state
, condition
);
1887 if (cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1888 evaluation
= lttng_evaluation_session_rotation_ongoing_create(
1889 trace_archive_chunk_id
);
1891 evaluation
= lttng_evaluation_session_rotation_completed_create(
1892 trace_archive_chunk_id
, location
);
1896 /* Internal error */
1898 cmd_result
= LTTNG_ERR_UNK
;
1903 * Ownership of `evaluation` transferred to the action executor
1904 * no matter the result.
1906 executor_status
= action_executor_enqueue(state
->executor
,
1907 trigger
, evaluation
, &session_creds
,
1910 switch (executor_status
) {
1911 case ACTION_EXECUTOR_STATUS_OK
:
1913 case ACTION_EXECUTOR_STATUS_ERROR
:
1914 case ACTION_EXECUTOR_STATUS_INVALID
:
1916 * TODO Add trigger identification (name/id) when
1917 * it is added to the API.
1919 ERR("Fatal error occurred while enqueuing action associated with session rotation trigger");
1922 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
1924 * TODO Add trigger identification (name/id) when
1925 * it is added to the API.
1927 * Not a fatal error.
1929 WARN("No space left when enqueuing action associated with session rotation trigger");
1937 notification_client_list_put(client_list
);
1938 if (caa_unlikely(ret
)) {
1943 session_info_put(session_info
);
1944 *_cmd_result
= cmd_result
;
1950 int handle_notification_thread_command_add_tracer_event_source(
1951 struct notification_thread_state
*state
,
1952 int tracer_event_source_fd
,
1953 enum lttng_domain_type domain_type
,
1954 enum lttng_error_code
*_cmd_result
)
1957 enum lttng_error_code cmd_result
= LTTNG_OK
;
1958 struct notification_event_tracer_event_source_element
*element
= NULL
;
1960 element
= zmalloc(sizeof(*element
));
1962 cmd_result
= LTTNG_ERR_NOMEM
;
1967 element
->fd
= tracer_event_source_fd
;
1968 element
->domain
= domain_type
;
1970 cds_list_add(&element
->node
, &state
->tracer_event_sources_list
);
1972 DBG3("[notification-thread] Adding tracer event source fd to poll set: tracer_event_source_fd = %d, domain = '%s'",
1973 tracer_event_source_fd
,
1974 lttng_domain_type_str(domain_type
));
1976 /* Adding the read side pipe to the event poll. */
1977 ret
= lttng_poll_add(&state
->events
, tracer_event_source_fd
, LPOLLIN
| LPOLLERR
);
1979 ERR("[notification-thread] Failed to add tracer event source to poll set: tracer_event_source_fd = %d, domain = '%s'",
1980 tracer_event_source_fd
,
1981 lttng_domain_type_str(element
->domain
));
1982 cds_list_del(&element
->node
);
1987 element
->is_fd_in_poll_set
= true;
1990 *_cmd_result
= cmd_result
;
1995 int drain_event_notifier_notification_pipe(
1996 struct notification_thread_state
*state
,
1997 int pipe
, enum lttng_domain_type domain
)
1999 struct lttng_poll_event events
= {0};
2002 ret
= lttng_poll_create(&events
, 1, LTTNG_CLOEXEC
);
2004 ERR("[notification-thread] Error creating lttng_poll_event");
2008 ret
= lttng_poll_add(&events
, pipe
, LPOLLIN
);
2010 ERR("[notification-thread] Error adding fd event notifier notification pipe to lttng_poll_event: fd = %d",
2017 * Continue to consume notifications as long as there are new
2018 * ones coming in. The tracer has been asked to stop producing
2021 * LPOLLIN is explicitly checked since LPOLLHUP is implicitly
2022 * monitored (on Linux, at least) and will be returned when
2023 * the pipe is closed but empty.
2025 ret
= lttng_poll_wait_interruptible(&events
, 0);
2026 if (ret
== 0 || (LTTNG_POLL_GETEV(&events
, 0) & LPOLLIN
) == 0) {
2027 /* No more notification to be read on this pipe. */
2030 } else if (ret
< 0) {
2031 PERROR("Failed on lttng_poll_wait_interruptible() call");
2036 ret
= handle_one_event_notifier_notification(state
, pipe
, domain
);
2038 ERR("[notification-thread] Error consuming an event notifier notification from pipe: fd = %d",
2043 lttng_poll_clean(&events
);
2048 int handle_notification_thread_command_remove_tracer_event_source(
2049 struct notification_thread_state
*state
,
2050 int tracer_event_source_fd
,
2051 enum lttng_error_code
*_cmd_result
)
2055 enum lttng_error_code cmd_result
= LTTNG_OK
;
2056 struct notification_event_tracer_event_source_element
*source_element
= NULL
, *tmp
;
2058 cds_list_for_each_entry_safe(source_element
, tmp
,
2059 &state
->tracer_event_sources_list
, node
) {
2060 if (source_element
->fd
!= tracer_event_source_fd
) {
2064 DBG("[notification-thread] Removed tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2065 tracer_event_source_fd
,
2066 lttng_domain_type_str(source_element
->domain
));
2067 cds_list_del(&source_element
->node
);
2074 * This is temporarily allowed since the poll activity set is
2075 * not properly cleaned-up for the moment. This is adressed in
2078 source_element
= NULL
;
2082 if (!source_element
->is_fd_in_poll_set
) {
2083 /* Skip the poll set removal. */
2087 DBG3("[notification-thread] Removing tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2088 tracer_event_source_fd
,
2089 lttng_domain_type_str(source_element
->domain
));
2091 /* Removing the fd from the event poll set. */
2092 ret
= lttng_poll_del(&state
->events
, tracer_event_source_fd
);
2094 ERR("[notification-thread] Failed to remove tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2095 tracer_event_source_fd
,
2096 lttng_domain_type_str(source_element
->domain
));
2097 cmd_result
= LTTNG_ERR_FATAL
;
2101 source_element
->is_fd_in_poll_set
= false;
2103 ret
= drain_event_notifier_notification_pipe(state
, tracer_event_source_fd
,
2104 source_element
->domain
);
2106 ERR("[notification-thread] Error draining event notifier notification: tracer_event_source_fd = %d, domain = %s",
2107 tracer_event_source_fd
,
2108 lttng_domain_type_str(source_element
->domain
));
2109 cmd_result
= LTTNG_ERR_FATAL
;
2114 * The drain_event_notifier_notification_pipe() call might have read
2115 * data from an fd that we received in event in the latest _poll_wait()
2116 * call. Make sure the thread call poll_wait() again to ensure we have
2119 state
->restart_poll
= true;
2122 free(source_element
);
2123 *_cmd_result
= cmd_result
;
2128 int condition_on_event_update_error_count(struct lttng_trigger
*trigger
)
2131 uint64_t error_count
= 0;
2132 struct lttng_condition
*condition
;
2133 enum event_notifier_error_accounting_status status
;
2135 condition
= lttng_trigger_get_condition(trigger
);
2136 assert(lttng_condition_get_type(condition
) ==
2137 LTTNG_CONDITION_TYPE_ON_EVENT
);
2139 status
= event_notifier_error_accounting_get_count(trigger
, &error_count
);
2140 if (status
!= EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK
) {
2141 uid_t trigger_owner_uid
;
2142 const char *trigger_name
;
2143 const enum lttng_trigger_status trigger_status
=
2144 lttng_trigger_get_owner_uid(
2145 trigger
, &trigger_owner_uid
);
2147 assert(trigger_status
== LTTNG_TRIGGER_STATUS_OK
);
2148 if (lttng_trigger_get_name(trigger
, &trigger_name
) != LTTNG_TRIGGER_STATUS_OK
) {
2149 trigger_name
= "(unnamed)";
2152 ERR("Failed to get event notifier error count of trigger for update: trigger owner = %d, trigger name = '%s'",
2153 trigger_owner_uid
, trigger_name
);
2157 lttng_condition_on_event_set_error_count(condition
, error_count
);
2161 int handle_notification_thread_remove_tracer_event_source_no_result(
2162 struct notification_thread_state
*state
,
2163 int tracer_event_source_fd
)
2166 enum lttng_error_code cmd_result
;
2168 ret
= handle_notification_thread_command_remove_tracer_event_source(
2169 state
, tracer_event_source_fd
, &cmd_result
);
2174 static int handle_notification_thread_command_list_triggers(
2175 struct notification_thread_handle
*handle
,
2176 struct notification_thread_state
*state
,
2178 struct lttng_triggers
**triggers
,
2179 enum lttng_error_code
*_cmd_result
)
2182 enum lttng_error_code cmd_result
= LTTNG_OK
;
2183 struct cds_lfht_iter iter
;
2184 struct lttng_trigger_ht_element
*trigger_ht_element
;
2185 struct lttng_triggers
*local_triggers
= NULL
;
2186 const struct lttng_credentials
*creds
;
2190 local_triggers
= lttng_triggers_create();
2191 if (!local_triggers
) {
2192 /* Not a fatal error. */
2193 cmd_result
= LTTNG_ERR_NOMEM
;
2197 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
,
2198 trigger_ht_element
, node
) {
2200 * Only return the triggers to which the client has access.
2201 * The root user has visibility over all triggers.
2203 creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
2204 if (client_uid
!= lttng_credentials_get_uid(creds
) && client_uid
!= 0) {
2208 if (lttng_trigger_needs_tracer_notifier(trigger_ht_element
->trigger
)) {
2209 ret
= condition_on_event_update_error_count(
2210 trigger_ht_element
->trigger
);
2214 ret
= lttng_triggers_add(local_triggers
,
2215 trigger_ht_element
->trigger
);
2217 /* Not a fatal error. */
2219 cmd_result
= LTTNG_ERR_NOMEM
;
2224 /* Transferring ownership to the caller. */
2225 *triggers
= local_triggers
;
2226 local_triggers
= NULL
;
2230 lttng_triggers_destroy(local_triggers
);
2231 *_cmd_result
= cmd_result
;
2236 bool condition_is_supported(struct lttng_condition
*condition
)
2240 switch (lttng_condition_get_type(condition
)) {
2241 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
2242 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
2245 enum lttng_domain_type domain
;
2247 ret
= lttng_condition_buffer_usage_get_domain_type(condition
,
2251 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2252 is_supported
= true;
2257 * Older kernel tracers don't expose the API to monitor their
2258 * buffers. Therefore, we reject triggers that require that
2259 * mechanism to be available to be evaluated.
2261 * Assume unsupported on error.
2263 is_supported
= kernel_supports_ring_buffer_snapshot_sample_positions() == 1;
2266 case LTTNG_CONDITION_TYPE_ON_EVENT
:
2268 const struct lttng_event_rule
*event_rule
;
2269 enum lttng_domain_type domain
;
2270 const enum lttng_condition_status status
=
2271 lttng_condition_on_event_get_rule(
2272 condition
, &event_rule
);
2274 assert(status
== LTTNG_CONDITION_STATUS_OK
);
2276 domain
= lttng_event_rule_get_domain_type(event_rule
);
2277 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2278 is_supported
= true;
2283 * Older kernel tracers can't emit notification. Therefore, we
2284 * reject triggers that require that mechanism to be available
2287 * Assume unsupported on error.
2289 is_supported
= kernel_supports_event_notifiers() == 1;
2293 is_supported
= true;
2296 return is_supported
;
2299 /* Must be called with RCU read lock held. */
2301 int bind_trigger_to_matching_session(struct lttng_trigger
*trigger
,
2302 struct notification_thread_state
*state
)
2305 const struct lttng_condition
*condition
;
2306 const char *session_name
;
2307 struct lttng_session_trigger_list
*trigger_list
;
2309 condition
= lttng_trigger_get_const_condition(trigger
);
2310 switch (lttng_condition_get_type(condition
)) {
2311 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
2312 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
2314 enum lttng_condition_status status
;
2316 status
= lttng_condition_session_rotation_get_session_name(
2317 condition
, &session_name
);
2318 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
2319 ERR("[notification-thread] Failed to bind trigger to session: unable to get 'session_rotation' condition's session name");
2330 trigger_list
= get_session_trigger_list(state
, session_name
);
2331 if (!trigger_list
) {
2332 DBG("[notification-thread] Unable to bind trigger applying to session \"%s\" as it is not yet known to the notification system",
2338 DBG("[notification-thread] Newly registered trigger bound to session \"%s\"",
2340 ret
= lttng_session_trigger_list_add(trigger_list
, trigger
);
2345 /* Must be called with RCU read lock held. */
2347 int bind_trigger_to_matching_channels(struct lttng_trigger
*trigger
,
2348 struct notification_thread_state
*state
)
2351 struct cds_lfht_node
*node
;
2352 struct cds_lfht_iter iter
;
2353 struct channel_info
*channel
;
2355 cds_lfht_for_each_entry(state
->channels_ht
, &iter
, channel
,
2357 struct lttng_trigger_list_element
*trigger_list_element
;
2358 struct lttng_channel_trigger_list
*trigger_list
;
2359 struct cds_lfht_iter lookup_iter
;
2361 if (!trigger_applies_to_channel(trigger
, channel
)) {
2365 cds_lfht_lookup(state
->channel_triggers_ht
,
2366 hash_channel_key(&channel
->key
),
2367 match_channel_trigger_list
,
2370 node
= cds_lfht_iter_get_node(&lookup_iter
);
2372 trigger_list
= caa_container_of(node
,
2373 struct lttng_channel_trigger_list
,
2374 channel_triggers_ht_node
);
2376 trigger_list_element
= zmalloc(sizeof(*trigger_list_element
));
2377 if (!trigger_list_element
) {
2381 CDS_INIT_LIST_HEAD(&trigger_list_element
->node
);
2382 trigger_list_element
->trigger
= trigger
;
2383 cds_list_add(&trigger_list_element
->node
, &trigger_list
->list
);
2384 DBG("[notification-thread] Newly registered trigger bound to channel \"%s\"",
2392 bool is_trigger_action_notify(const struct lttng_trigger
*trigger
)
2394 bool is_notify
= false;
2395 unsigned int i
, count
;
2396 enum lttng_action_status action_status
;
2397 const struct lttng_action
*action
=
2398 lttng_trigger_get_const_action(trigger
);
2399 enum lttng_action_type action_type
;
2402 action_type
= lttng_action_get_type(action
);
2403 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2406 } else if (action_type
!= LTTNG_ACTION_TYPE_GROUP
) {
2410 action_status
= lttng_action_group_get_count(action
, &count
);
2411 assert(action_status
== LTTNG_ACTION_STATUS_OK
);
2413 for (i
= 0; i
< count
; i
++) {
2414 const struct lttng_action
*inner_action
=
2415 lttng_action_group_get_at_index(
2418 action_type
= lttng_action_get_type(inner_action
);
2419 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2429 static bool trigger_name_taken(struct notification_thread_state
*state
,
2430 const struct lttng_trigger
*trigger
)
2432 struct cds_lfht_iter iter
;
2435 * No duplicata is allowed in the triggers_by_name_uid_ht.
2436 * The match is done against the trigger name and uid.
2438 cds_lfht_lookup(state
->triggers_by_name_uid_ht
,
2439 hash_trigger_by_name_uid(trigger
),
2440 match_trigger_by_name_uid
,
2443 return !!cds_lfht_iter_get_node(&iter
);
2447 enum lttng_error_code
generate_trigger_name(
2448 struct notification_thread_state
*state
,
2449 struct lttng_trigger
*trigger
, const char **name
)
2451 enum lttng_error_code ret_code
= LTTNG_OK
;
2453 enum lttng_trigger_status status
;
2456 const int ret
= lttng_trigger_generate_name(trigger
,
2457 state
->trigger_id
.name_offset
++);
2459 /* The only reason this can fail right now. */
2460 ret_code
= LTTNG_ERR_NOMEM
;
2464 status
= lttng_trigger_get_name(trigger
, name
);
2465 assert(status
== LTTNG_TRIGGER_STATUS_OK
);
2467 taken
= trigger_name_taken(state
, trigger
);
2468 } while (taken
|| state
->trigger_id
.name_offset
== UINT64_MAX
);
2474 void notif_thread_state_remove_trigger_ht_elem(
2475 struct notification_thread_state
*state
,
2476 struct lttng_trigger_ht_element
*trigger_ht_element
)
2479 assert(trigger_ht_element
);
2481 cds_lfht_del(state
->triggers_ht
, &trigger_ht_element
->node
);
2482 cds_lfht_del(state
->triggers_by_name_uid_ht
, &trigger_ht_element
->node_by_name_uid
);
2486 enum lttng_error_code
setup_tracer_notifier(
2487 struct notification_thread_state
*state
,
2488 struct lttng_trigger
*trigger
)
2490 enum lttng_error_code ret
;
2491 enum event_notifier_error_accounting_status error_accounting_status
;
2492 struct cds_lfht_node
*node
;
2493 uint64_t error_counter_index
= 0;
2494 struct lttng_condition
*condition
= lttng_trigger_get_condition(trigger
);
2495 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
= NULL
;
2497 trigger_tokens_ht_element
= zmalloc(sizeof(*trigger_tokens_ht_element
));
2498 if (!trigger_tokens_ht_element
) {
2499 ret
= LTTNG_ERR_NOMEM
;
2503 /* Add trigger token to the trigger_tokens_ht. */
2504 cds_lfht_node_init(&trigger_tokens_ht_element
->node
);
2505 trigger_tokens_ht_element
->token
= LTTNG_OPTIONAL_GET(trigger
->tracer_token
);
2506 trigger_tokens_ht_element
->trigger
= trigger
;
2508 node
= cds_lfht_add_unique(state
->trigger_tokens_ht
,
2509 hash_key_u64(&trigger_tokens_ht_element
->token
, lttng_ht_seed
),
2510 match_trigger_token
,
2511 &trigger_tokens_ht_element
->token
,
2512 &trigger_tokens_ht_element
->node
);
2513 if (node
!= &trigger_tokens_ht_element
->node
) {
2514 ret
= LTTNG_ERR_TRIGGER_EXISTS
;
2515 goto error_free_ht_element
;
2518 error_accounting_status
= event_notifier_error_accounting_register_event_notifier(
2519 trigger
, &error_counter_index
);
2520 if (error_accounting_status
!= EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK
) {
2521 if (error_accounting_status
== EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_NO_INDEX_AVAILABLE
) {
2522 DBG("Trigger group error accounting counter full.");
2523 ret
= LTTNG_ERR_EVENT_NOTIFIER_ERROR_ACCOUNTING_FULL
;
2525 ERR("Error registering trigger for error accounting");
2526 ret
= LTTNG_ERR_EVENT_NOTIFIER_REGISTRATION
;
2529 goto error_remove_ht_element
;
2532 lttng_condition_on_event_set_error_counter_index(
2533 condition
, error_counter_index
);
2538 error_remove_ht_element
:
2539 cds_lfht_del(state
->trigger_tokens_ht
, &trigger_tokens_ht_element
->node
);
2540 error_free_ht_element
:
2541 free(trigger_tokens_ht_element
);
2547 * FIXME A client's credentials are not checked when registering a trigger.
2549 * The effects of this are benign since:
2550 * - The client will succeed in registering the trigger, as it is valid,
2551 * - The trigger will, internally, be bound to the channel/session,
2552 * - The notifications will not be sent since the client's credentials
2553 * are checked against the channel at that moment.
2555 * If this function returns a non-zero value, it means something is
2556 * fundamentally broken and the whole subsystem/thread will be torn down.
2558 * If a non-fatal error occurs, just set the cmd_result to the appropriate
2562 int handle_notification_thread_command_register_trigger(
2563 struct notification_thread_state
*state
,
2564 struct lttng_trigger
*trigger
,
2565 enum lttng_error_code
*cmd_result
)
2568 struct lttng_condition
*condition
;
2569 struct notification_client
*client
;
2570 struct notification_client_list
*client_list
= NULL
;
2571 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2572 struct notification_client_list_element
*client_list_element
;
2573 struct cds_lfht_node
*node
;
2574 struct cds_lfht_iter iter
;
2575 const char* trigger_name
;
2576 bool free_trigger
= true;
2577 struct lttng_evaluation
*evaluation
= NULL
;
2578 struct lttng_credentials object_creds
;
2581 enum action_executor_status executor_status
;
2582 const uint64_t trigger_tracer_token
=
2583 state
->trigger_id
.next_tracer_token
++;
2587 /* Set the trigger's tracer token. */
2588 lttng_trigger_set_tracer_token(trigger
, trigger_tracer_token
);
2590 if (lttng_trigger_get_name(trigger
, &trigger_name
) ==
2591 LTTNG_TRIGGER_STATUS_UNSET
) {
2592 const enum lttng_error_code ret_code
= generate_trigger_name(
2593 state
, trigger
, &trigger_name
);
2595 if (ret_code
!= LTTNG_OK
) {
2598 *cmd_result
= ret_code
;
2601 } else if (trigger_name_taken(state
, trigger
)) {
2602 /* Not a fatal error. */
2603 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2608 condition
= lttng_trigger_get_condition(trigger
);
2611 /* Some conditions require tracers to implement a minimal ABI version. */
2612 if (!condition_is_supported(condition
)) {
2613 *cmd_result
= LTTNG_ERR_NOT_SUPPORTED
;
2617 trigger_ht_element
= zmalloc(sizeof(*trigger_ht_element
));
2618 if (!trigger_ht_element
) {
2623 /* Add trigger to the trigger_ht. */
2624 cds_lfht_node_init(&trigger_ht_element
->node
);
2625 cds_lfht_node_init(&trigger_ht_element
->node_by_name_uid
);
2626 trigger_ht_element
->trigger
= trigger
;
2628 node
= cds_lfht_add_unique(state
->triggers_ht
,
2629 lttng_condition_hash(condition
),
2632 &trigger_ht_element
->node
);
2633 if (node
!= &trigger_ht_element
->node
) {
2634 /* Not a fatal error, simply report it to the client. */
2635 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2636 goto error_free_ht_element
;
2639 node
= cds_lfht_add_unique(state
->triggers_by_name_uid_ht
,
2640 hash_trigger_by_name_uid(trigger
),
2641 match_trigger_by_name_uid
,
2643 &trigger_ht_element
->node_by_name_uid
);
2644 if (node
!= &trigger_ht_element
->node_by_name_uid
) {
2645 /* Not a fatal error, simply report it to the client. */
2646 cds_lfht_del(state
->triggers_ht
, &trigger_ht_element
->node
);
2647 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2648 goto error_free_ht_element
;
2652 * Some triggers might need a tracer notifier depending on its
2653 * condition and actions.
2655 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
2656 enum lttng_error_code error_code
;
2658 error_code
= setup_tracer_notifier(state
, trigger
);
2659 if (error_code
!= LTTNG_OK
) {
2660 notif_thread_state_remove_trigger_ht_elem(state
,
2661 trigger_ht_element
);
2662 if (error_code
== LTTNG_ERR_NOMEM
) {
2665 *cmd_result
= error_code
;
2669 goto error_free_ht_element
;
2674 * Ownership of the trigger and of its wrapper was transfered to
2675 * the triggers_ht. Same for token ht element if necessary.
2677 trigger_ht_element
= NULL
;
2678 free_trigger
= false;
2681 * The rest only applies to triggers that have a "notify" action.
2682 * It is not skipped as this is the only action type currently
2685 if (is_trigger_action_notify(trigger
)) {
2686 client_list
= notification_client_list_create(trigger
);
2689 goto error_free_ht_element
;
2692 /* Build a list of clients to which this new trigger applies. */
2693 cds_lfht_for_each_entry (state
->client_socket_ht
, &iter
, client
,
2694 client_socket_ht_node
) {
2695 if (!trigger_applies_to_client(trigger
, client
)) {
2699 client_list_element
=
2700 zmalloc(sizeof(*client_list_element
));
2701 if (!client_list_element
) {
2703 goto error_put_client_list
;
2706 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
2707 client_list_element
->client
= client
;
2708 cds_list_add(&client_list_element
->node
,
2709 &client_list
->list
);
2713 * Client list ownership transferred to the
2714 * notification_trigger_clients_ht.
2716 publish_notification_client_list(state
, client_list
);
2719 switch (get_condition_binding_object(condition
)) {
2720 case LTTNG_OBJECT_TYPE_SESSION
:
2721 /* Add the trigger to the list if it matches a known session. */
2722 ret
= bind_trigger_to_matching_session(trigger
, state
);
2724 goto error_put_client_list
;
2727 case LTTNG_OBJECT_TYPE_CHANNEL
:
2729 * Add the trigger to list of triggers bound to the channels
2732 ret
= bind_trigger_to_matching_channels(trigger
, state
);
2734 goto error_put_client_list
;
2737 case LTTNG_OBJECT_TYPE_NONE
:
2740 ERR("Unknown object type on which to bind a newly registered trigger was encountered");
2742 goto error_put_client_list
;
2746 * The new trigger's condition must be evaluated against the current
2749 * In the case of `notify` action, nothing preventing clients from
2750 * subscribing to a condition before the corresponding trigger is
2751 * registered, we have to evaluate this new condition right away.
2753 * At some point, we were waiting for the next "evaluation" (e.g. on
2754 * reception of a channel sample) to evaluate this new condition, but
2757 * The reason it was broken is that waiting for the next sample
2758 * does not allow us to properly handle transitions for edge-triggered
2761 * Consider this example: when we handle a new channel sample, we
2762 * evaluate each conditions twice: once with the previous state, and
2763 * again with the newest state. We then use those two results to
2764 * determine whether a state change happened: a condition was false and
2765 * became true. If a state change happened, we have to notify clients.
2767 * Now, if a client subscribes to a given notification and registers
2768 * a trigger *after* that subscription, we have to make sure the
2769 * condition is evaluated at this point while considering only the
2770 * current state. Otherwise, the next evaluation cycle may only see
2771 * that the evaluations remain the same (true for samples n-1 and n) and
2772 * the client will never know that the condition has been met.
2774 switch (get_condition_binding_object(condition
)) {
2775 case LTTNG_OBJECT_TYPE_SESSION
:
2776 ret
= evaluate_session_condition_for_client(condition
, state
,
2777 &evaluation
, &object_uid
,
2779 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2780 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2782 case LTTNG_OBJECT_TYPE_CHANNEL
:
2783 ret
= evaluate_channel_condition_for_client(condition
, state
,
2784 &evaluation
, &object_uid
,
2786 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2787 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2789 case LTTNG_OBJECT_TYPE_NONE
:
2792 case LTTNG_OBJECT_TYPE_UNKNOWN
:
2800 goto error_put_client_list
;
2803 DBG("Newly registered trigger's condition evaluated to %s",
2804 evaluation
? "true" : "false");
2806 /* Evaluation yielded nothing. Normal exit. */
2812 * Ownership of `evaluation` transferred to the action executor
2813 * no matter the result.
2815 executor_status
= action_executor_enqueue(state
->executor
, trigger
,
2816 evaluation
, &object_creds
, client_list
);
2818 switch (executor_status
) {
2819 case ACTION_EXECUTOR_STATUS_OK
:
2821 case ACTION_EXECUTOR_STATUS_ERROR
:
2822 case ACTION_EXECUTOR_STATUS_INVALID
:
2824 * TODO Add trigger identification (name/id) when
2825 * it is added to the API.
2827 ERR("Fatal error occurred while enqueuing action associated to newly registered trigger");
2829 goto error_put_client_list
;
2830 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
2832 * TODO Add trigger identification (name/id) when
2833 * it is added to the API.
2835 * Not a fatal error.
2837 WARN("No space left when enqueuing action associated to newly registered trigger");
2845 *cmd_result
= LTTNG_OK
;
2846 DBG("Registered trigger: name = `%s`, tracer token = %" PRIu64
,
2847 trigger_name
, trigger_tracer_token
);
2849 error_put_client_list
:
2850 notification_client_list_put(client_list
);
2852 error_free_ht_element
:
2853 if (trigger_ht_element
) {
2854 /* Delayed removal due to RCU constraint on delete. */
2855 call_rcu(&trigger_ht_element
->rcu_node
,
2856 free_lttng_trigger_ht_element_rcu
);
2860 lttng_trigger_destroy(trigger
);
2867 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
)
2869 free(caa_container_of(node
, struct lttng_trigger_ht_element
,
2874 void free_notification_trigger_tokens_ht_element_rcu(struct rcu_head
*node
)
2876 free(caa_container_of(node
, struct notification_trigger_tokens_ht_element
,
2881 void teardown_tracer_notifier(struct notification_thread_state
*state
,
2882 const struct lttng_trigger
*trigger
)
2884 struct cds_lfht_iter iter
;
2885 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
;
2887 cds_lfht_for_each_entry(state
->trigger_tokens_ht
, &iter
,
2888 trigger_tokens_ht_element
, node
) {
2890 if (!lttng_trigger_is_equal(trigger
,
2891 trigger_tokens_ht_element
->trigger
)) {
2895 event_notifier_error_accounting_unregister_event_notifier(
2896 trigger_tokens_ht_element
->trigger
);
2898 /* TODO talk to all app and remove it */
2899 DBG("[notification-thread] Removed trigger from tokens_ht");
2900 cds_lfht_del(state
->trigger_tokens_ht
,
2901 &trigger_tokens_ht_element
->node
);
2903 call_rcu(&trigger_tokens_ht_element
->rcu_node
,
2904 free_notification_trigger_tokens_ht_element_rcu
);
2911 int handle_notification_thread_command_unregister_trigger(
2912 struct notification_thread_state
*state
,
2913 const struct lttng_trigger
*trigger
,
2914 enum lttng_error_code
*_cmd_reply
)
2916 struct cds_lfht_iter iter
;
2917 struct cds_lfht_node
*triggers_ht_node
;
2918 struct lttng_channel_trigger_list
*trigger_list
;
2919 struct notification_client_list
*client_list
;
2920 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2921 const struct lttng_condition
*condition
= lttng_trigger_get_const_condition(
2923 enum lttng_error_code cmd_reply
;
2927 cds_lfht_lookup(state
->triggers_ht
,
2928 lttng_condition_hash(condition
),
2932 triggers_ht_node
= cds_lfht_iter_get_node(&iter
);
2933 if (!triggers_ht_node
) {
2934 cmd_reply
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
2937 cmd_reply
= LTTNG_OK
;
2940 /* Remove trigger from channel_triggers_ht. */
2941 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
, trigger_list
,
2942 channel_triggers_ht_node
) {
2943 struct lttng_trigger_list_element
*trigger_element
, *tmp
;
2945 cds_list_for_each_entry_safe(trigger_element
, tmp
,
2946 &trigger_list
->list
, node
) {
2947 if (!lttng_trigger_is_equal(trigger
, trigger_element
->trigger
)) {
2951 DBG("[notification-thread] Removed trigger from channel_triggers_ht");
2952 cds_list_del(&trigger_element
->node
);
2953 /* A trigger can only appear once per channel */
2958 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
2959 teardown_tracer_notifier(state
, trigger
);
2962 if (is_trigger_action_notify(trigger
)) {
2964 * Remove and release the client list from
2965 * notification_trigger_clients_ht.
2967 client_list
= get_client_list_from_condition(state
, condition
);
2968 assert(client_list
);
2970 /* Put new reference and the hashtable's reference. */
2971 notification_client_list_put(client_list
);
2972 notification_client_list_put(client_list
);
2976 trigger_ht_element
= caa_container_of(triggers_ht_node
,
2977 struct lttng_trigger_ht_element
, node
);
2979 /* Remove trigger from triggers_ht. */
2980 notif_thread_state_remove_trigger_ht_elem(state
, trigger_ht_element
);
2982 /* Release the ownership of the trigger. */
2983 lttng_trigger_destroy(trigger_ht_element
->trigger
);
2984 call_rcu(&trigger_ht_element
->rcu_node
, free_lttng_trigger_ht_element_rcu
);
2988 *_cmd_reply
= cmd_reply
;
2993 /* Returns 0 on success, 1 on exit requested, negative value on error. */
2994 int handle_notification_thread_command(
2995 struct notification_thread_handle
*handle
,
2996 struct notification_thread_state
*state
)
3000 struct notification_thread_command
*cmd
;
3002 /* Read the event pipe to put it back into a quiescent state. */
3003 ret
= lttng_read(lttng_pipe_get_readfd(handle
->cmd_queue
.event_pipe
), &counter
,
3005 if (ret
!= sizeof(counter
)) {
3009 pthread_mutex_lock(&handle
->cmd_queue
.lock
);
3010 cmd
= cds_list_first_entry(&handle
->cmd_queue
.list
,
3011 struct notification_thread_command
, cmd_list_node
);
3012 cds_list_del(&cmd
->cmd_list_node
);
3013 pthread_mutex_unlock(&handle
->cmd_queue
.lock
);
3015 DBG("[notification-thread] Received `%s` command",
3016 notification_command_type_str(cmd
->type
));
3017 switch (cmd
->type
) {
3018 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
3019 ret
= handle_notification_thread_command_register_trigger(state
,
3020 cmd
->parameters
.register_trigger
.trigger
,
3023 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
3024 ret
= handle_notification_thread_command_unregister_trigger(
3026 cmd
->parameters
.unregister_trigger
.trigger
,
3029 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
3030 ret
= handle_notification_thread_command_add_channel(
3032 cmd
->parameters
.add_channel
.session
.name
,
3033 cmd
->parameters
.add_channel
.session
.uid
,
3034 cmd
->parameters
.add_channel
.session
.gid
,
3035 cmd
->parameters
.add_channel
.channel
.name
,
3036 cmd
->parameters
.add_channel
.channel
.domain
,
3037 cmd
->parameters
.add_channel
.channel
.key
,
3038 cmd
->parameters
.add_channel
.channel
.capacity
,
3041 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
3042 ret
= handle_notification_thread_command_remove_channel(
3043 state
, cmd
->parameters
.remove_channel
.key
,
3044 cmd
->parameters
.remove_channel
.domain
,
3047 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
3048 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
3049 ret
= handle_notification_thread_command_session_rotation(
3052 cmd
->parameters
.session_rotation
.session_name
,
3053 cmd
->parameters
.session_rotation
.uid
,
3054 cmd
->parameters
.session_rotation
.gid
,
3055 cmd
->parameters
.session_rotation
.trace_archive_chunk_id
,
3056 cmd
->parameters
.session_rotation
.location
,
3059 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
3060 ret
= handle_notification_thread_command_add_tracer_event_source(
3062 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3063 cmd
->parameters
.tracer_event_source
.domain
,
3066 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
3067 ret
= handle_notification_thread_command_remove_tracer_event_source(
3069 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3072 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
3074 struct lttng_triggers
*triggers
= NULL
;
3076 ret
= handle_notification_thread_command_list_triggers(
3079 cmd
->parameters
.list_triggers
.uid
,
3082 cmd
->reply
.list_triggers
.triggers
= triggers
;
3086 case NOTIFICATION_COMMAND_TYPE_QUIT
:
3087 cmd
->reply_code
= LTTNG_OK
;
3090 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
3092 const enum client_transmission_status client_status
=
3093 cmd
->parameters
.client_communication_update
3095 const notification_client_id client_id
=
3096 cmd
->parameters
.client_communication_update
.id
;
3097 struct notification_client
*client
;
3100 client
= get_client_from_id(client_id
, state
);
3104 * Client error was probably already picked-up by the
3105 * notification thread or it has disconnected
3106 * gracefully while this command was queued.
3108 DBG("Failed to find notification client to update communication status, client id = %" PRIu64
,
3112 ret
= client_handle_transmission_status(
3113 client
, client_status
, state
);
3119 ERR("[notification-thread] Unknown internal command received");
3127 if (cmd
->is_async
) {
3131 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3135 /* Wake-up and return a fatal error to the calling thread. */
3136 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3137 cmd
->reply_code
= LTTNG_ERR_FATAL
;
3139 /* Indicate a fatal error to the caller. */
3144 int socket_set_non_blocking(int socket
)
3148 /* Set the pipe as non-blocking. */
3149 ret
= fcntl(socket
, F_GETFL
, 0);
3151 PERROR("fcntl get socket flags");
3156 ret
= fcntl(socket
, F_SETFL
, flags
| O_NONBLOCK
);
3158 PERROR("fcntl set O_NONBLOCK socket flag");
3161 DBG("Client socket (fd = %i) set as non-blocking", socket
);
3167 int client_reset_inbound_state(struct notification_client
*client
)
3172 lttng_payload_clear(&client
->communication
.inbound
.payload
);
3174 client
->communication
.inbound
.bytes_to_receive
=
3175 sizeof(struct lttng_notification_channel_message
);
3176 client
->communication
.inbound
.msg_type
=
3177 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
;
3178 LTTNG_SOCK_SET_UID_CRED(&client
->communication
.inbound
.creds
, -1);
3179 LTTNG_SOCK_SET_GID_CRED(&client
->communication
.inbound
.creds
, -1);
3180 ret
= lttng_dynamic_buffer_set_size(
3181 &client
->communication
.inbound
.payload
.buffer
,
3182 client
->communication
.inbound
.bytes_to_receive
);
3187 int handle_notification_thread_client_connect(
3188 struct notification_thread_state
*state
)
3191 struct notification_client
*client
;
3193 DBG("[notification-thread] Handling new notification channel client connection");
3195 client
= zmalloc(sizeof(*client
));
3202 pthread_mutex_init(&client
->lock
, NULL
);
3203 client
->id
= state
->next_notification_client_id
++;
3204 CDS_INIT_LIST_HEAD(&client
->condition_list
);
3205 lttng_payload_init(&client
->communication
.inbound
.payload
);
3206 lttng_payload_init(&client
->communication
.outbound
.payload
);
3207 client
->communication
.inbound
.expect_creds
= true;
3209 ret
= client_reset_inbound_state(client
);
3211 ERR("[notification-thread] Failed to reset client communication's inbound state");
3216 ret
= lttcomm_accept_unix_sock(state
->notification_channel_socket
);
3218 ERR("[notification-thread] Failed to accept new notification channel client connection");
3223 client
->socket
= ret
;
3225 ret
= socket_set_non_blocking(client
->socket
);
3227 ERR("[notification-thread] Failed to set new notification channel client connection socket as non-blocking");
3231 ret
= lttcomm_setsockopt_creds_unix_sock(client
->socket
);
3233 ERR("[notification-thread] Failed to set socket options on new notification channel client socket");
3238 ret
= lttng_poll_add(&state
->events
, client
->socket
,
3239 LPOLLIN
| LPOLLERR
|
3240 LPOLLHUP
| LPOLLRDHUP
);
3242 ERR("[notification-thread] Failed to add notification channel client socket to poll set");
3246 DBG("[notification-thread] Added new notification channel client socket (%i) to poll set",
3250 cds_lfht_add(state
->client_socket_ht
,
3251 hash_client_socket(client
->socket
),
3252 &client
->client_socket_ht_node
);
3253 cds_lfht_add(state
->client_id_ht
,
3254 hash_client_id(client
->id
),
3255 &client
->client_id_ht_node
);
3261 notification_client_destroy(client
, state
);
3266 * RCU read-lock must be held by the caller.
3267 * Client lock must _not_ be held by the caller.
3270 int notification_thread_client_disconnect(
3271 struct notification_client
*client
,
3272 struct notification_thread_state
*state
)
3275 struct lttng_condition_list_element
*condition_list_element
, *tmp
;
3277 /* Acquire the client lock to disable its communication atomically. */
3278 pthread_mutex_lock(&client
->lock
);
3279 client
->communication
.active
= false;
3280 cds_lfht_del(state
->client_socket_ht
, &client
->client_socket_ht_node
);
3281 cds_lfht_del(state
->client_id_ht
, &client
->client_id_ht_node
);
3282 pthread_mutex_unlock(&client
->lock
);
3284 ret
= lttng_poll_del(&state
->events
, client
->socket
);
3286 ERR("[notification-thread] Failed to remove client socket %d from poll set",
3290 /* Release all conditions to which the client was subscribed. */
3291 cds_list_for_each_entry_safe(condition_list_element
, tmp
,
3292 &client
->condition_list
, node
) {
3293 (void) notification_thread_client_unsubscribe(client
,
3294 condition_list_element
->condition
, state
, NULL
);
3298 * Client no longer accessible to other threads (through the
3301 notification_client_destroy(client
, state
);
3305 int handle_notification_thread_client_disconnect(
3306 int client_socket
, struct notification_thread_state
*state
)
3309 struct notification_client
*client
;
3312 DBG("[notification-thread] Closing client connection (socket fd = %i)",
3314 client
= get_client_from_socket(client_socket
, state
);
3316 /* Internal state corruption, fatal error. */
3317 ERR("[notification-thread] Unable to find client (socket fd = %i)",
3323 ret
= notification_thread_client_disconnect(client
, state
);
3329 int handle_notification_thread_client_disconnect_all(
3330 struct notification_thread_state
*state
)
3332 struct cds_lfht_iter iter
;
3333 struct notification_client
*client
;
3334 bool error_encoutered
= false;
3337 DBG("[notification-thread] Closing all client connections");
3338 cds_lfht_for_each_entry(state
->client_socket_ht
, &iter
, client
,
3339 client_socket_ht_node
) {
3342 ret
= notification_thread_client_disconnect(
3345 error_encoutered
= true;
3349 return error_encoutered
? 1 : 0;
3352 int handle_notification_thread_trigger_unregister_all(
3353 struct notification_thread_state
*state
)
3355 bool error_occurred
= false;
3356 struct cds_lfht_iter iter
;
3357 struct lttng_trigger_ht_element
*trigger_ht_element
;
3360 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
3362 int ret
= handle_notification_thread_command_unregister_trigger(
3363 state
, trigger_ht_element
->trigger
, NULL
);
3365 error_occurred
= true;
3369 return error_occurred
? -1 : 0;
3373 int client_handle_transmission_status(
3374 struct notification_client
*client
,
3375 enum client_transmission_status transmission_status
,
3376 struct notification_thread_state
*state
)
3380 switch (transmission_status
) {
3381 case CLIENT_TRANSMISSION_STATUS_COMPLETE
:
3382 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3383 CLIENT_POLL_MASK_IN
);
3389 case CLIENT_TRANSMISSION_STATUS_QUEUED
:
3391 * We want to be notified whenever there is buffer space
3392 * available to send the rest of the payload.
3394 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3395 CLIENT_POLL_MASK_IN_OUT
);
3400 case CLIENT_TRANSMISSION_STATUS_FAIL
:
3401 ret
= notification_thread_client_disconnect(client
, state
);
3406 case CLIENT_TRANSMISSION_STATUS_ERROR
:
3416 /* Client lock must be acquired by caller. */
3418 enum client_transmission_status
client_flush_outgoing_queue(
3419 struct notification_client
*client
)
3422 size_t to_send_count
;
3423 enum client_transmission_status status
;
3424 struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3425 &client
->communication
.outbound
.payload
, 0, -1);
3426 const int fds_to_send_count
=
3427 lttng_payload_view_get_fd_handle_count(&pv
);
3429 ASSERT_LOCKED(client
->lock
);
3431 if (!client
->communication
.active
) {
3432 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3436 if (pv
.buffer
.size
== 0) {
3438 * If both data and fds are equal to zero, we are in an invalid
3441 assert(fds_to_send_count
!= 0);
3446 to_send_count
= pv
.buffer
.size
;
3447 DBG("[notification-thread] Flushing client (socket fd = %i) outgoing queue",
3450 ret
= lttcomm_send_unix_sock_non_block(client
->socket
,
3453 if ((ret
>= 0 && ret
< to_send_count
)) {
3454 DBG("[notification-thread] Client (socket fd = %i) outgoing queue could not be completely flushed",
3456 to_send_count
-= max(ret
, 0);
3458 memmove(client
->communication
.outbound
.payload
.buffer
.data
,
3460 pv
.buffer
.size
- to_send_count
,
3462 ret
= lttng_dynamic_buffer_set_size(
3463 &client
->communication
.outbound
.payload
.buffer
,
3469 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3471 } else if (ret
< 0) {
3472 /* Generic error, disable the client's communication. */
3473 ERR("[notification-thread] Failed to flush outgoing queue, disconnecting client (socket fd = %i)",
3475 client
->communication
.active
= false;
3476 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3480 * No error and flushed the queue completely.
3482 * The payload buffer size is used later to
3483 * check if there is notifications queued. So albeit that the
3484 * direct caller knows that the transmission is complete, we
3485 * need to set the buffer size to zero.
3487 ret
= lttng_dynamic_buffer_set_size(
3488 &client
->communication
.outbound
.payload
.buffer
, 0);
3495 /* No fds to send, transmission is complete. */
3496 if (fds_to_send_count
== 0) {
3497 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3501 ret
= lttcomm_send_payload_view_fds_unix_sock_non_block(
3502 client
->socket
, &pv
);
3504 /* Generic error, disable the client's communication. */
3505 ERR("[notification-thread] Failed to flush outgoing fds queue, disconnecting client (socket fd = %i)",
3507 client
->communication
.active
= false;
3508 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3510 } else if (ret
== 0) {
3511 /* Nothing could be sent. */
3512 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3514 /* Fd passing is an all or nothing kind of thing. */
3515 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3517 * The payload _fd_array count is used later to
3518 * check if there is notifications queued. So although the
3519 * direct caller knows that the transmission is complete, we
3520 * need to clear the _fd_array for the queuing check.
3522 lttng_dynamic_pointer_array_clear(
3523 &client
->communication
.outbound
.payload
3528 if (status
== CLIENT_TRANSMISSION_STATUS_COMPLETE
) {
3529 client
->communication
.outbound
.queued_command_reply
= false;
3530 client
->communication
.outbound
.dropped_notification
= false;
3531 lttng_payload_clear(&client
->communication
.outbound
.payload
);
3536 return CLIENT_TRANSMISSION_STATUS_ERROR
;
3540 bool client_has_outbound_data_left(
3541 const struct notification_client
*client
)
3543 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3544 &client
->communication
.outbound
.payload
, 0, -1);
3545 const bool has_data
= pv
.buffer
.size
!= 0;
3546 const bool has_fds
= lttng_payload_view_get_fd_handle_count(&pv
);
3548 return has_data
|| has_fds
;
3551 /* Client lock must _not_ be held by the caller. */
3553 int client_send_command_reply(struct notification_client
*client
,
3554 struct notification_thread_state
*state
,
3555 enum lttng_notification_channel_status status
)
3558 struct lttng_notification_channel_command_reply reply
= {
3559 .status
= (int8_t) status
,
3561 struct lttng_notification_channel_message msg
= {
3562 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY
,
3563 .size
= sizeof(reply
),
3565 char buffer
[sizeof(msg
) + sizeof(reply
)];
3566 enum client_transmission_status transmission_status
;
3568 memcpy(buffer
, &msg
, sizeof(msg
));
3569 memcpy(buffer
+ sizeof(msg
), &reply
, sizeof(reply
));
3570 DBG("[notification-thread] Send command reply (%i)", (int) status
);
3572 pthread_mutex_lock(&client
->lock
);
3573 if (client
->communication
.outbound
.queued_command_reply
) {
3574 /* Protocol error. */
3578 /* Enqueue buffer to outgoing queue and flush it. */
3579 ret
= lttng_dynamic_buffer_append(
3580 &client
->communication
.outbound
.payload
.buffer
,
3581 buffer
, sizeof(buffer
));
3586 transmission_status
= client_flush_outgoing_queue(client
);
3588 if (client_has_outbound_data_left(client
)) {
3589 /* Queue could not be emptied. */
3590 client
->communication
.outbound
.queued_command_reply
= true;
3593 pthread_mutex_unlock(&client
->lock
);
3594 ret
= client_handle_transmission_status(
3595 client
, transmission_status
, state
);
3602 pthread_mutex_unlock(&client
->lock
);
3608 int client_handle_message_unknown(struct notification_client
*client
,
3609 struct notification_thread_state
*state
)
3613 * Receiving message header. The function will be called again
3614 * once the rest of the message as been received and can be
3617 const struct lttng_notification_channel_message
*msg
;
3619 assert(sizeof(*msg
) == client
->communication
.inbound
.payload
.buffer
.size
);
3620 msg
= (const struct lttng_notification_channel_message
*)
3621 client
->communication
.inbound
.payload
.buffer
.data
;
3623 if (msg
->size
== 0 ||
3624 msg
->size
> DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE
) {
3625 ERR("[notification-thread] Invalid notification channel message: length = %u",
3631 switch (msg
->type
) {
3632 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3633 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3634 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3638 ERR("[notification-thread] Invalid notification channel message: unexpected message type");
3642 client
->communication
.inbound
.bytes_to_receive
= msg
->size
;
3643 client
->communication
.inbound
.fds_to_receive
= msg
->fds
;
3644 client
->communication
.inbound
.msg_type
=
3645 (enum lttng_notification_channel_message_type
) msg
->type
;
3646 ret
= lttng_dynamic_buffer_set_size(
3647 &client
->communication
.inbound
.payload
.buffer
, msg
->size
);
3649 /* msg is not valid anymore due to lttng_dynamic_buffer_set_size. */
3656 int client_handle_message_handshake(struct notification_client
*client
,
3657 struct notification_thread_state
*state
)
3660 struct lttng_notification_channel_command_handshake
*handshake_client
;
3661 const struct lttng_notification_channel_command_handshake handshake_reply
= {
3662 .major
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
,
3663 .minor
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR
,
3665 const struct lttng_notification_channel_message msg_header
= {
3666 .type
= LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
,
3667 .size
= sizeof(handshake_reply
),
3669 enum lttng_notification_channel_status status
=
3670 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3671 char send_buffer
[sizeof(msg_header
) + sizeof(handshake_reply
)];
3673 memcpy(send_buffer
, &msg_header
, sizeof(msg_header
));
3674 memcpy(send_buffer
+ sizeof(msg_header
), &handshake_reply
,
3675 sizeof(handshake_reply
));
3678 (struct lttng_notification_channel_command_handshake
*)
3679 client
->communication
.inbound
.payload
.buffer
3681 client
->major
= handshake_client
->major
;
3682 client
->minor
= handshake_client
->minor
;
3683 if (!client
->communication
.inbound
.creds_received
) {
3684 ERR("[notification-thread] No credentials received from client");
3689 client
->uid
= LTTNG_SOCK_GET_UID_CRED(
3690 &client
->communication
.inbound
.creds
);
3691 client
->gid
= LTTNG_SOCK_GET_GID_CRED(
3692 &client
->communication
.inbound
.creds
);
3693 DBG("[notification-thread] Received handshake from client (uid = %u, gid = %u) with version %i.%i",
3694 client
->uid
, client
->gid
, (int) client
->major
,
3695 (int) client
->minor
);
3697 if (handshake_client
->major
!=
3698 LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
) {
3699 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION
;
3702 pthread_mutex_lock(&client
->lock
);
3703 /* Outgoing queue will be flushed when the command reply is sent. */
3704 ret
= lttng_dynamic_buffer_append(
3705 &client
->communication
.outbound
.payload
.buffer
, send_buffer
,
3706 sizeof(send_buffer
));
3708 ERR("[notification-thread] Failed to send protocol version to notification channel client");
3712 client
->validated
= true;
3713 client
->communication
.active
= true;
3714 pthread_mutex_unlock(&client
->lock
);
3716 /* Set reception state to receive the next message header. */
3717 ret
= client_reset_inbound_state(client
);
3719 ERR("[notification-thread] Failed to reset client communication's inbound state");
3723 /* Flushes the outgoing queue. */
3724 ret
= client_send_command_reply(client
, state
, status
);
3726 ERR("[notification-thread] Failed to send reply to notification channel client");
3732 pthread_mutex_unlock(&client
->lock
);
3738 int client_handle_message_subscription(
3739 struct notification_client
*client
,
3740 enum lttng_notification_channel_message_type msg_type
,
3741 struct notification_thread_state
*state
)
3744 struct lttng_condition
*condition
;
3745 enum lttng_notification_channel_status status
=
3746 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3747 struct lttng_payload_view condition_view
=
3748 lttng_payload_view_from_payload(
3749 &client
->communication
.inbound
.payload
,
3751 size_t expected_condition_size
;
3754 * No need to lock client to sample the inbound state as the only
3755 * other thread accessing clients (action executor) only uses the
3758 expected_condition_size
= client
->communication
.inbound
.payload
.buffer
.size
;
3759 ret
= lttng_condition_create_from_payload(&condition_view
, &condition
);
3760 if (ret
!= expected_condition_size
) {
3761 ERR("[notification-thread] Malformed condition received from client");
3765 if (msg_type
== LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
) {
3766 ret
= notification_thread_client_subscribe(
3767 client
, condition
, state
, &status
);
3769 ret
= notification_thread_client_unsubscribe(
3770 client
, condition
, state
, &status
);
3777 /* Set reception state to receive the next message header. */
3778 ret
= client_reset_inbound_state(client
);
3780 ERR("[notification-thread] Failed to reset client communication's inbound state");
3784 ret
= client_send_command_reply(client
, state
, status
);
3786 ERR("[notification-thread] Failed to send reply to notification channel client");
3795 int client_dispatch_message(struct notification_client
*client
,
3796 struct notification_thread_state
*state
)
3800 if (client
->communication
.inbound
.msg_type
!=
3801 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
&&
3802 client
->communication
.inbound
.msg_type
!=
3803 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
&&
3804 !client
->validated
) {
3805 WARN("[notification-thread] client attempted a command before handshake");
3810 switch (client
->communication
.inbound
.msg_type
) {
3811 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
:
3813 ret
= client_handle_message_unknown(client
, state
);
3816 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3818 ret
= client_handle_message_handshake(client
, state
);
3821 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3822 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3824 ret
= client_handle_message_subscription(client
,
3825 client
->communication
.inbound
.msg_type
, state
);
3835 /* Incoming data from client. */
3836 int handle_notification_thread_client_in(
3837 struct notification_thread_state
*state
, int socket
)
3840 struct notification_client
*client
;
3845 client
= get_client_from_socket(socket
, state
);
3847 /* Internal error, abort. */
3852 offset
= client
->communication
.inbound
.payload
.buffer
.size
-
3853 client
->communication
.inbound
.bytes_to_receive
;
3854 if (client
->communication
.inbound
.expect_creds
) {
3855 recv_ret
= lttcomm_recv_creds_unix_sock(socket
,
3856 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
3857 client
->communication
.inbound
.bytes_to_receive
,
3858 &client
->communication
.inbound
.creds
);
3860 client
->communication
.inbound
.expect_creds
= false;
3861 client
->communication
.inbound
.creds_received
= true;
3864 recv_ret
= lttcomm_recv_unix_sock_non_block(socket
,
3865 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
3866 client
->communication
.inbound
.bytes_to_receive
);
3868 if (recv_ret
>= 0) {
3869 client
->communication
.inbound
.bytes_to_receive
-= recv_ret
;
3871 goto error_disconnect_client
;
3874 if (client
->communication
.inbound
.bytes_to_receive
!= 0) {
3875 /* Message incomplete wait for more data. */
3880 assert(client
->communication
.inbound
.bytes_to_receive
== 0);
3883 if (client
->communication
.inbound
.fds_to_receive
!= 0) {
3884 ret
= lttcomm_recv_payload_fds_unix_sock_non_block(
3886 client
->communication
.inbound
.fds_to_receive
,
3887 &client
->communication
.inbound
.payload
);
3890 * Fds received. non blocking fds passing is all
3893 ssize_t expected_size
;
3895 expected_size
= sizeof(int) *
3896 client
->communication
.inbound
3898 assert(ret
== expected_size
);
3899 client
->communication
.inbound
.fds_to_receive
= 0;
3900 } else if (ret
== 0) {
3901 /* Received nothing. */
3905 goto error_disconnect_client
;
3909 /* At this point the message is complete.*/
3910 assert(client
->communication
.inbound
.bytes_to_receive
== 0 &&
3911 client
->communication
.inbound
.fds_to_receive
== 0);
3912 ret
= client_dispatch_message(client
, state
);
3915 * Only returns an error if this client must be
3918 goto error_disconnect_client
;
3925 error_disconnect_client
:
3926 ret
= notification_thread_client_disconnect(client
, state
);
3930 /* Client ready to receive outgoing data. */
3931 int handle_notification_thread_client_out(
3932 struct notification_thread_state
*state
, int socket
)
3935 struct notification_client
*client
;
3936 enum client_transmission_status transmission_status
;
3939 client
= get_client_from_socket(socket
, state
);
3941 /* Internal error, abort. */
3946 pthread_mutex_lock(&client
->lock
);
3947 transmission_status
= client_flush_outgoing_queue(client
);
3948 pthread_mutex_unlock(&client
->lock
);
3950 ret
= client_handle_transmission_status(
3951 client
, transmission_status
, state
);
3961 bool evaluate_buffer_usage_condition(const struct lttng_condition
*condition
,
3962 const struct channel_state_sample
*sample
,
3963 uint64_t buffer_capacity
)
3965 bool result
= false;
3967 enum lttng_condition_type condition_type
;
3968 const struct lttng_condition_buffer_usage
*use_condition
= container_of(
3969 condition
, struct lttng_condition_buffer_usage
,
3972 if (use_condition
->threshold_bytes
.set
) {
3973 threshold
= use_condition
->threshold_bytes
.value
;
3976 * Threshold was expressed as a ratio.
3978 * TODO the threshold (in bytes) of conditions expressed
3979 * as a ratio of total buffer size could be cached to
3980 * forego this double-multiplication or it could be performed
3981 * as fixed-point math.
3983 * Note that caching should accommodates the case where the
3984 * condition applies to multiple channels (i.e. don't assume
3985 * that all channels matching my_chann* have the same size...)
3987 threshold
= (uint64_t) (use_condition
->threshold_ratio
.value
*
3988 (double) buffer_capacity
);
3991 condition_type
= lttng_condition_get_type(condition
);
3992 if (condition_type
== LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
) {
3993 DBG("[notification-thread] Low buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
3994 threshold
, sample
->highest_usage
);
3997 * The low condition should only be triggered once _all_ of the
3998 * streams in a channel have gone below the "low" threshold.
4000 if (sample
->highest_usage
<= threshold
) {
4004 DBG("[notification-thread] High buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4005 threshold
, sample
->highest_usage
);
4008 * For high buffer usage scenarios, we want to trigger whenever
4009 * _any_ of the streams has reached the "high" threshold.
4011 if (sample
->highest_usage
>= threshold
) {
4020 bool evaluate_session_consumed_size_condition(
4021 const struct lttng_condition
*condition
,
4022 uint64_t session_consumed_size
)
4025 const struct lttng_condition_session_consumed_size
*size_condition
=
4026 container_of(condition
,
4027 struct lttng_condition_session_consumed_size
,
4030 threshold
= size_condition
->consumed_threshold_bytes
.value
;
4031 DBG("[notification-thread] Session consumed size condition being evaluated: threshold = %" PRIu64
", current size = %" PRIu64
,
4032 threshold
, session_consumed_size
);
4033 return session_consumed_size
>= threshold
;
4037 int evaluate_buffer_condition(const struct lttng_condition
*condition
,
4038 struct lttng_evaluation
**evaluation
,
4039 const struct notification_thread_state
*state
,
4040 const struct channel_state_sample
*previous_sample
,
4041 const struct channel_state_sample
*latest_sample
,
4042 uint64_t previous_session_consumed_total
,
4043 uint64_t latest_session_consumed_total
,
4044 struct channel_info
*channel_info
)
4047 enum lttng_condition_type condition_type
;
4048 const bool previous_sample_available
= !!previous_sample
;
4049 bool previous_sample_result
= false;
4050 bool latest_sample_result
;
4052 condition_type
= lttng_condition_get_type(condition
);
4054 switch (condition_type
) {
4055 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4056 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4057 if (caa_likely(previous_sample_available
)) {
4058 previous_sample_result
=
4059 evaluate_buffer_usage_condition(condition
,
4060 previous_sample
, channel_info
->capacity
);
4062 latest_sample_result
= evaluate_buffer_usage_condition(
4063 condition
, latest_sample
,
4064 channel_info
->capacity
);
4066 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
4067 if (caa_likely(previous_sample_available
)) {
4068 previous_sample_result
=
4069 evaluate_session_consumed_size_condition(
4071 previous_session_consumed_total
);
4073 latest_sample_result
=
4074 evaluate_session_consumed_size_condition(
4076 latest_session_consumed_total
);
4079 /* Unknown condition type; internal error. */
4083 if (!latest_sample_result
||
4084 (previous_sample_result
== latest_sample_result
)) {
4086 * Only trigger on a condition evaluation transition.
4088 * NOTE: This edge-triggered logic may not be appropriate for
4089 * future condition types.
4094 if (!evaluation
|| !latest_sample_result
) {
4098 switch (condition_type
) {
4099 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4100 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4101 *evaluation
= lttng_evaluation_buffer_usage_create(
4103 latest_sample
->highest_usage
,
4104 channel_info
->capacity
);
4106 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
4107 *evaluation
= lttng_evaluation_session_consumed_size_create(
4108 latest_session_consumed_total
);
4123 int client_notification_overflow(struct notification_client
*client
)
4126 const struct lttng_notification_channel_message msg
= {
4127 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED
,
4130 ASSERT_LOCKED(client
->lock
);
4132 DBG("Dropping notification addressed to client (socket fd = %i)",
4134 if (client
->communication
.outbound
.dropped_notification
) {
4136 * The client already has a "notification dropped" message
4137 * in its outgoing queue. Nothing to do since all
4138 * of those messages are coalesced.
4143 client
->communication
.outbound
.dropped_notification
= true;
4144 ret
= lttng_dynamic_buffer_append(
4145 &client
->communication
.outbound
.payload
.buffer
, &msg
,
4148 PERROR("Failed to enqueue \"dropped notification\" message in client's (socket fd = %i) outgoing queue",
4155 static int client_handle_transmission_status_wrapper(
4156 struct notification_client
*client
,
4157 enum client_transmission_status status
,
4160 return client_handle_transmission_status(client
, status
,
4161 (struct notification_thread_state
*) user_data
);
4165 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
4166 const struct lttng_evaluation
*evaluation
,
4167 struct notification_client_list
* client_list
,
4168 struct notification_thread_state
*state
,
4169 uid_t object_uid
, gid_t object_gid
)
4171 const struct lttng_credentials creds
= {
4172 .uid
= LTTNG_OPTIONAL_INIT_VALUE(object_uid
),
4173 .gid
= LTTNG_OPTIONAL_INIT_VALUE(object_gid
),
4176 return notification_client_list_send_evaluation(client_list
,
4177 lttng_trigger_get_const_condition(trigger
), evaluation
,
4178 lttng_trigger_get_credentials(trigger
),
4180 client_handle_transmission_status_wrapper
, state
);
4184 * Permission checks relative to notification channel clients are performed
4185 * here. Notice how object, client, and trigger credentials are involved in
4188 * The `object` credentials are the credentials associated with the "subject"
4189 * of a condition. For instance, a `rotation completed` condition applies
4190 * to a session. When that condition is met, it will produce an evaluation
4191 * against a session. Hence, in this case, the `object` credentials are the
4192 * credentials of the "subject" session.
4194 * The `trigger` credentials are the credentials of the user that registered the
4197 * The `client` credentials are the credentials of the user that created a given
4198 * notification channel.
4200 * In terms of visibility, it is expected that non-privilieged users can only
4201 * register triggers against "their" objects (their own sessions and
4202 * applications they are allowed to interact with). They can then open a
4203 * notification channel and subscribe to notifications associated with those
4206 * As for privilieged users, they can register triggers against the objects of
4207 * other users. They can then subscribe to the notifications associated to their
4208 * triggers. Privilieged users _can't_ subscribe to the notifications of
4209 * triggers owned by other users; they must create their own triggers.
4211 * This is more a concern of usability than security. It would be difficult for
4212 * a root user reliably subscribe to a specific set of conditions without
4213 * interference from external users (those could, for instance, unregister
4217 int notification_client_list_send_evaluation(
4218 struct notification_client_list
*client_list
,
4219 const struct lttng_condition
*condition
,
4220 const struct lttng_evaluation
*evaluation
,
4221 const struct lttng_credentials
*trigger_creds
,
4222 const struct lttng_credentials
*source_object_creds
,
4223 report_client_transmission_result_cb client_report
,
4227 struct lttng_payload msg_payload
;
4228 struct notification_client_list_element
*client_list_element
, *tmp
;
4229 const struct lttng_notification notification
= {
4230 .condition
= (struct lttng_condition
*) condition
,
4231 .evaluation
= (struct lttng_evaluation
*) evaluation
,
4233 struct lttng_notification_channel_message msg_header
= {
4234 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION
,
4237 lttng_payload_init(&msg_payload
);
4239 ret
= lttng_dynamic_buffer_append(&msg_payload
.buffer
, &msg_header
,
4240 sizeof(msg_header
));
4245 ret
= lttng_notification_serialize(¬ification
, &msg_payload
);
4247 ERR("[notification-thread] Failed to serialize notification");
4252 /* Update payload size. */
4253 ((struct lttng_notification_channel_message
*) msg_payload
.buffer
.data
)
4254 ->size
= (uint32_t)(
4255 msg_payload
.buffer
.size
- sizeof(msg_header
));
4257 /* Update the payload number of fds. */
4259 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
4260 &msg_payload
, 0, -1);
4262 ((struct lttng_notification_channel_message
*)
4263 msg_payload
.buffer
.data
)->fds
= (uint32_t)
4264 lttng_payload_view_get_fd_handle_count(&pv
);
4267 pthread_mutex_lock(&client_list
->lock
);
4268 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4269 &client_list
->list
, node
) {
4270 enum client_transmission_status transmission_status
;
4271 struct notification_client
*client
=
4272 client_list_element
->client
;
4275 pthread_mutex_lock(&client
->lock
);
4276 if (!client
->communication
.active
) {
4278 * Skip inactive client (protocol error or
4281 DBG("Skipping client at it is marked as inactive");
4285 if (source_object_creds
) {
4286 if (client
->uid
!= lttng_credentials_get_uid(source_object_creds
) &&
4287 client
->gid
!= lttng_credentials_get_gid(source_object_creds
) &&
4290 * Client is not allowed to monitor this
4293 DBG("[notification-thread] Skipping client at it does not have the object permission to receive notification for this trigger");
4298 if (client
->uid
!= lttng_credentials_get_uid(trigger_creds
) && client
->gid
!= lttng_credentials_get_gid(trigger_creds
)) {
4299 DBG("[notification-thread] Skipping client at it does not have the permission to receive notification for this trigger");
4303 DBG("[notification-thread] Sending notification to client (fd = %i, %zu bytes)",
4304 client
->socket
, msg_payload
.buffer
.size
);
4306 if (client_has_outbound_data_left(client
)) {
4308 * Outgoing data is already buffered for this client;
4309 * drop the notification and enqueue a "dropped
4310 * notification" message if this is the first dropped
4311 * notification since the socket spilled-over to the
4314 ret
= client_notification_overflow(client
);
4321 ret
= lttng_payload_copy(&msg_payload
, &client
->communication
.outbound
.payload
);
4327 transmission_status
= client_flush_outgoing_queue(client
);
4328 pthread_mutex_unlock(&client
->lock
);
4329 ret
= client_report(client
, transmission_status
, user_data
);
4332 goto end_unlock_list
;
4338 pthread_mutex_unlock(&client
->lock
);
4341 goto end_unlock_list
;
4347 pthread_mutex_unlock(&client_list
->lock
);
4349 lttng_payload_reset(&msg_payload
);
4354 struct lttng_event_notifier_notification
*recv_one_event_notifier_notification(
4355 int notification_pipe_read_fd
, enum lttng_domain_type domain
)
4359 struct lttng_event_notifier_notification
*notification
= NULL
;
4360 char *capture_buffer
= NULL
;
4361 size_t capture_buffer_size
;
4362 void *reception_buffer
;
4363 size_t reception_size
;
4365 struct lttng_ust_abi_event_notifier_notification ust_notification
;
4366 struct lttng_kernel_event_notifier_notification kernel_notification
;
4368 /* Init lttng_event_notifier_notification */
4370 case LTTNG_DOMAIN_UST
:
4371 reception_buffer
= (void *) &ust_notification
;
4372 reception_size
= sizeof(ust_notification
);
4374 case LTTNG_DOMAIN_KERNEL
:
4375 reception_buffer
= (void *) &kernel_notification
;
4376 reception_size
= sizeof(kernel_notification
);
4383 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4384 * ensuring that read/write of tracer notifications are atomic.
4386 ret
= lttng_read(notification_pipe_read_fd
, reception_buffer
,
4388 if (ret
!= reception_size
) {
4389 PERROR("Failed to read from event source notification pipe: fd = %d, size to read = %zu, ret = %d",
4390 notification_pipe_read_fd
, reception_size
, ret
);
4396 case LTTNG_DOMAIN_UST
:
4397 token
= ust_notification
.token
;
4398 capture_buffer_size
= ust_notification
.capture_buf_size
;
4400 case LTTNG_DOMAIN_KERNEL
:
4401 token
= kernel_notification
.token
;
4402 capture_buffer_size
= kernel_notification
.capture_buf_size
;
4408 if (capture_buffer_size
== 0) {
4409 capture_buffer
= NULL
;
4413 if (capture_buffer_size
> MAX_CAPTURE_SIZE
) {
4414 ERR("[notification-thread] Event notifier has a capture payload size which exceeds the maximum allowed size: capture_payload_size = %zu bytes, max allowed size = %d bytes",
4415 capture_buffer_size
, MAX_CAPTURE_SIZE
);
4419 capture_buffer
= zmalloc(capture_buffer_size
);
4420 if (!capture_buffer
) {
4421 ERR("[notification-thread] Failed to allocate capture buffer");
4425 /* Fetch additional payload (capture). */
4426 ret
= lttng_read(notification_pipe_read_fd
, capture_buffer
, capture_buffer_size
);
4427 if (ret
!= capture_buffer_size
) {
4428 ERR("[notification-thread] Failed to read from event source pipe (fd = %i)",
4429 notification_pipe_read_fd
);
4434 notification
= lttng_event_notifier_notification_create(token
, domain
,
4435 capture_buffer
, capture_buffer_size
);
4436 if (notification
== NULL
) {
4441 * Ownership transfered to the lttng_event_notifier_notification object.
4443 capture_buffer
= NULL
;
4446 free(capture_buffer
);
4447 return notification
;
4451 int dispatch_one_event_notifier_notification(struct notification_thread_state
*state
,
4452 struct lttng_event_notifier_notification
*notification
)
4454 struct cds_lfht_node
*node
;
4455 struct cds_lfht_iter iter
;
4456 struct notification_trigger_tokens_ht_element
*element
;
4457 enum lttng_trigger_status trigger_status
;
4458 struct lttng_evaluation
*evaluation
= NULL
;
4459 enum action_executor_status executor_status
;
4460 struct notification_client_list
*client_list
= NULL
;
4461 const char *trigger_name
;
4463 unsigned int capture_count
= 0;
4465 /* Find triggers associated with this token. */
4467 cds_lfht_lookup(state
->trigger_tokens_ht
,
4468 hash_key_u64(¬ification
->tracer_token
, lttng_ht_seed
),
4469 match_trigger_token
, ¬ification
->tracer_token
, &iter
);
4470 node
= cds_lfht_iter_get_node(&iter
);
4471 if (caa_unlikely(!node
)) {
4473 * This is not an error, slow consumption of the tracer
4474 * notifications can lead to situations where a trigger is
4475 * removed but we still get tracer notifications matching a
4476 * trigger that no longer exists.
4482 element
= caa_container_of(node
,
4483 struct notification_trigger_tokens_ht_element
,
4486 if (!lttng_trigger_should_fire(element
->trigger
)) {
4491 lttng_trigger_fire(element
->trigger
);
4493 trigger_status
= lttng_trigger_get_name(element
->trigger
, &trigger_name
);
4494 assert(trigger_status
== LTTNG_TRIGGER_STATUS_OK
);
4496 if (lttng_condition_on_event_get_capture_descriptor_count(
4497 lttng_trigger_get_const_condition(element
->trigger
),
4498 &capture_count
) != LTTNG_CONDITION_STATUS_OK
) {
4499 ERR("Failed to get capture count");
4504 if (!notification
->capture_buffer
&& capture_count
!= 0) {
4505 ERR("Expected capture but capture buffer is null");
4510 evaluation
= lttng_evaluation_on_event_create(
4511 container_of(lttng_trigger_get_const_condition(
4513 struct lttng_condition_on_event
,
4516 notification
->capture_buffer
,
4517 notification
->capture_buf_size
, false);
4519 if (evaluation
== NULL
) {
4520 ERR("[notification-thread] Failed to create event rule hit evaluation while creating and enqueuing action executor job");
4524 client_list
= get_client_list_from_condition(state
,
4525 lttng_trigger_get_const_condition(element
->trigger
));
4526 executor_status
= action_executor_enqueue(state
->executor
,
4527 element
->trigger
, evaluation
, NULL
, client_list
);
4528 switch (executor_status
) {
4529 case ACTION_EXECUTOR_STATUS_OK
:
4532 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4534 struct notification_client_list_element
*client_list_element
,
4538 * Not a fatal error; this is expected and simply means the
4539 * executor has too much work queued already.
4543 /* No clients subscribed to notifications for this trigger. */
4548 /* Warn clients that a notification (or more) was dropped. */
4549 pthread_mutex_lock(&client_list
->lock
);
4550 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4551 &client_list
->list
, node
) {
4552 enum client_transmission_status transmission_status
;
4553 struct notification_client
*client
=
4554 client_list_element
->client
;
4556 pthread_mutex_lock(&client
->lock
);
4557 ret
= client_notification_overflow(client
);
4563 transmission_status
=
4564 client_flush_outgoing_queue(client
);
4565 ret
= client_handle_transmission_status(
4566 client
, transmission_status
, state
);
4572 pthread_mutex_unlock(&client
->lock
);
4578 pthread_mutex_unlock(&client_list
->lock
);
4581 case ACTION_EXECUTOR_STATUS_INVALID
:
4582 case ACTION_EXECUTOR_STATUS_ERROR
:
4583 /* Fatal error, shut down everything. */
4584 ERR("Fatal error encoutered while enqueuing action to the action executor");
4588 /* Unhandled error. */
4593 notification_client_list_put(client_list
);
4600 int handle_one_event_notifier_notification(
4601 struct notification_thread_state
*state
,
4602 int pipe
, enum lttng_domain_type domain
)
4605 struct lttng_event_notifier_notification
*notification
= NULL
;
4607 notification
= recv_one_event_notifier_notification(pipe
, domain
);
4608 if (notification
== NULL
) {
4609 /* Reception failed, don't consider it fatal. */
4610 ERR("[notification-thread] Error receiving an event notifier notification from tracer: fd = %i, domain = %s",
4611 pipe
, lttng_domain_type_str(domain
));
4615 ret
= dispatch_one_event_notifier_notification(state
, notification
);
4617 ERR("[notification-thread] Error dispatching an event notifier notification from tracer: fd = %i, domain = %s",
4618 pipe
, lttng_domain_type_str(domain
));
4623 lttng_event_notifier_notification_destroy(notification
);
4627 int handle_notification_thread_event_notification(struct notification_thread_state
*state
,
4628 int pipe
, enum lttng_domain_type domain
)
4630 return handle_one_event_notifier_notification(state
, pipe
, domain
);
4633 int handle_notification_thread_channel_sample(
4634 struct notification_thread_state
*state
, int pipe
,
4635 enum lttng_domain_type domain
)
4638 struct lttcomm_consumer_channel_monitor_msg sample_msg
;
4639 struct channel_info
*channel_info
;
4640 struct cds_lfht_node
*node
;
4641 struct cds_lfht_iter iter
;
4642 struct lttng_channel_trigger_list
*trigger_list
;
4643 struct lttng_trigger_list_element
*trigger_list_element
;
4644 bool previous_sample_available
= false;
4645 struct channel_state_sample previous_sample
, latest_sample
;
4646 uint64_t previous_session_consumed_total
, latest_session_consumed_total
;
4647 struct lttng_credentials channel_creds
;
4650 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4651 * ensuring that read/write of sampling messages are atomic.
4653 ret
= lttng_read(pipe
, &sample_msg
, sizeof(sample_msg
));
4654 if (ret
!= sizeof(sample_msg
)) {
4655 ERR("[notification-thread] Failed to read from monitoring pipe (fd = %i)",
4662 latest_sample
.key
.key
= sample_msg
.key
;
4663 latest_sample
.key
.domain
= domain
;
4664 latest_sample
.highest_usage
= sample_msg
.highest
;
4665 latest_sample
.lowest_usage
= sample_msg
.lowest
;
4666 latest_sample
.channel_total_consumed
= sample_msg
.total_consumed
;
4670 /* Retrieve the channel's informations */
4671 cds_lfht_lookup(state
->channels_ht
,
4672 hash_channel_key(&latest_sample
.key
),
4676 node
= cds_lfht_iter_get_node(&iter
);
4677 if (caa_unlikely(!node
)) {
4679 * Not an error since the consumer can push a sample to the pipe
4680 * and the rest of the session daemon could notify us of the
4681 * channel's destruction before we get a chance to process that
4684 DBG("[notification-thread] Received a sample for an unknown channel from consumerd, key = %" PRIu64
" in %s domain",
4685 latest_sample
.key
.key
,
4686 lttng_domain_type_str(domain
));
4689 channel_info
= caa_container_of(node
, struct channel_info
,
4691 DBG("[notification-thread] Handling channel sample for channel %s (key = %" PRIu64
") in session %s (highest usage = %" PRIu64
", lowest usage = %" PRIu64
", total consumed = %" PRIu64
")",
4693 latest_sample
.key
.key
,
4694 channel_info
->session_info
->name
,
4695 latest_sample
.highest_usage
,
4696 latest_sample
.lowest_usage
,
4697 latest_sample
.channel_total_consumed
);
4699 previous_session_consumed_total
=
4700 channel_info
->session_info
->consumed_data_size
;
4702 /* Retrieve the channel's last sample, if it exists, and update it. */
4703 cds_lfht_lookup(state
->channel_state_ht
,
4704 hash_channel_key(&latest_sample
.key
),
4705 match_channel_state_sample
,
4708 node
= cds_lfht_iter_get_node(&iter
);
4709 if (caa_likely(node
)) {
4710 struct channel_state_sample
*stored_sample
;
4712 /* Update the sample stored. */
4713 stored_sample
= caa_container_of(node
,
4714 struct channel_state_sample
,
4715 channel_state_ht_node
);
4717 memcpy(&previous_sample
, stored_sample
,
4718 sizeof(previous_sample
));
4719 stored_sample
->highest_usage
= latest_sample
.highest_usage
;
4720 stored_sample
->lowest_usage
= latest_sample
.lowest_usage
;
4721 stored_sample
->channel_total_consumed
= latest_sample
.channel_total_consumed
;
4722 previous_sample_available
= true;
4724 latest_session_consumed_total
=
4725 previous_session_consumed_total
+
4726 (latest_sample
.channel_total_consumed
- previous_sample
.channel_total_consumed
);
4729 * This is the channel's first sample, allocate space for and
4730 * store the new sample.
4732 struct channel_state_sample
*stored_sample
;
4734 stored_sample
= zmalloc(sizeof(*stored_sample
));
4735 if (!stored_sample
) {
4740 memcpy(stored_sample
, &latest_sample
, sizeof(*stored_sample
));
4741 cds_lfht_node_init(&stored_sample
->channel_state_ht_node
);
4742 cds_lfht_add(state
->channel_state_ht
,
4743 hash_channel_key(&stored_sample
->key
),
4744 &stored_sample
->channel_state_ht_node
);
4746 latest_session_consumed_total
=
4747 previous_session_consumed_total
+
4748 latest_sample
.channel_total_consumed
;
4751 channel_info
->session_info
->consumed_data_size
=
4752 latest_session_consumed_total
;
4754 /* Find triggers associated with this channel. */
4755 cds_lfht_lookup(state
->channel_triggers_ht
,
4756 hash_channel_key(&latest_sample
.key
),
4757 match_channel_trigger_list
,
4760 node
= cds_lfht_iter_get_node(&iter
);
4761 if (caa_likely(!node
)) {
4765 channel_creds
= (typeof(channel_creds
)) {
4766 .uid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->uid
),
4767 .gid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->gid
),
4770 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
4771 channel_triggers_ht_node
);
4772 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
4774 const struct lttng_condition
*condition
;
4775 struct lttng_trigger
*trigger
;
4776 struct notification_client_list
*client_list
= NULL
;
4777 struct lttng_evaluation
*evaluation
= NULL
;
4778 enum action_executor_status executor_status
;
4781 trigger
= trigger_list_element
->trigger
;
4782 condition
= lttng_trigger_get_const_condition(trigger
);
4786 * Check if any client is subscribed to the result of this
4789 client_list
= get_client_list_from_condition(state
, condition
);
4791 ret
= evaluate_buffer_condition(condition
, &evaluation
, state
,
4792 previous_sample_available
? &previous_sample
: NULL
,
4794 previous_session_consumed_total
,
4795 latest_session_consumed_total
,
4797 if (caa_unlikely(ret
)) {
4801 if (caa_likely(!evaluation
)) {
4805 if (!lttng_trigger_should_fire(trigger
)) {
4809 lttng_trigger_fire(trigger
);
4812 * Ownership of `evaluation` transferred to the action executor
4813 * no matter the result.
4815 executor_status
= action_executor_enqueue(state
->executor
,
4816 trigger
, evaluation
, &channel_creds
,
4819 switch (executor_status
) {
4820 case ACTION_EXECUTOR_STATUS_OK
:
4822 case ACTION_EXECUTOR_STATUS_ERROR
:
4823 case ACTION_EXECUTOR_STATUS_INVALID
:
4825 * TODO Add trigger identification (name/id) when
4826 * it is added to the API.
4828 ERR("Fatal error occurred while enqueuing action associated with buffer-condition trigger");
4831 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4833 * TODO Add trigger identification (name/id) when
4834 * it is added to the API.
4836 * Not a fatal error.
4838 WARN("No space left when enqueuing action associated with buffer-condition trigger");
4846 notification_client_list_put(client_list
);
4847 if (caa_unlikely(ret
)) {