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/notification/notification-internal.h>
25 #include <lttng/condition/condition-internal.h>
26 #include <lttng/condition/buffer-usage-internal.h>
27 #include <lttng/condition/session-consumed-size-internal.h>
28 #include <lttng/condition/session-rotation-internal.h>
29 #include <lttng/condition/event-rule-internal.h>
30 #include <lttng/domain-internal.h>
31 #include <lttng/notification/channel-internal.h>
32 #include <lttng/trigger/trigger-internal.h>
33 #include <lttng/event-rule/event-rule-internal.h>
41 #include "condition-internal.h"
42 #include "notification-thread.h"
43 #include "notification-thread-events.h"
44 #include "notification-thread-commands.h"
45 #include "lttng-sessiond.h"
48 #define CLIENT_POLL_MASK_IN (LPOLLIN | LPOLLERR | LPOLLHUP | LPOLLRDHUP)
49 #define CLIENT_POLL_MASK_IN_OUT (CLIENT_POLL_MASK_IN | LPOLLOUT)
51 enum lttng_object_type
{
52 LTTNG_OBJECT_TYPE_UNKNOWN
,
53 LTTNG_OBJECT_TYPE_NONE
,
54 LTTNG_OBJECT_TYPE_CHANNEL
,
55 LTTNG_OBJECT_TYPE_SESSION
,
58 struct lttng_trigger_list_element
{
59 /* No ownership of the trigger object is assumed. */
60 struct lttng_trigger
*trigger
;
61 struct cds_list_head node
;
64 struct lttng_channel_trigger_list
{
65 struct channel_key channel_key
;
66 /* List of struct lttng_trigger_list_element. */
67 struct cds_list_head list
;
68 /* Node in the channel_triggers_ht */
69 struct cds_lfht_node channel_triggers_ht_node
;
70 /* call_rcu delayed reclaim. */
71 struct rcu_head rcu_node
;
75 * List of triggers applying to a given session.
78 * - lttng_session_trigger_list_create()
79 * - lttng_session_trigger_list_build()
80 * - lttng_session_trigger_list_destroy()
81 * - lttng_session_trigger_list_add()
83 struct lttng_session_trigger_list
{
85 * Not owned by this; points to the session_info structure's
88 const char *session_name
;
89 /* List of struct lttng_trigger_list_element. */
90 struct cds_list_head list
;
91 /* Node in the session_triggers_ht */
92 struct cds_lfht_node session_triggers_ht_node
;
94 * Weak reference to the notification system's session triggers
97 * The session trigger list structure structure is owned by
98 * the session's session_info.
100 * The session_info is kept alive the the channel_infos holding a
101 * reference to it (reference counting). When those channels are
102 * destroyed (at runtime or on teardown), the reference they hold
103 * to the session_info are released. On destruction of session_info,
104 * session_info_destroy() will remove the list of triggers applying
105 * to this session from the notification system's state.
107 * This implies that the session_triggers_ht must be destroyed
108 * after the channels.
110 struct cds_lfht
*session_triggers_ht
;
111 /* Used for delayed RCU reclaim. */
112 struct rcu_head rcu_node
;
115 struct lttng_trigger_ht_element
{
116 struct lttng_trigger
*trigger
;
117 struct cds_lfht_node node
;
118 struct cds_lfht_node node_by_name_uid
;
119 /* call_rcu delayed reclaim. */
120 struct rcu_head rcu_node
;
123 struct lttng_condition_list_element
{
124 struct lttng_condition
*condition
;
125 struct cds_list_head node
;
129 * Facilities to carry the different notifications type in the action processing
132 struct lttng_event_notifier_notification
{
134 struct lttng_ust_event_notifier_notification
*ust
;
135 struct lttng_kernel_event_notifier_notification
*kernel
;
138 enum lttng_domain_type type
;
141 struct channel_state_sample
{
142 struct channel_key key
;
143 struct cds_lfht_node channel_state_ht_node
;
144 uint64_t highest_usage
;
145 uint64_t lowest_usage
;
146 uint64_t channel_total_consumed
;
147 /* call_rcu delayed reclaim. */
148 struct rcu_head rcu_node
;
151 static unsigned long hash_channel_key(struct channel_key
*key
);
152 static int evaluate_buffer_condition(const struct lttng_condition
*condition
,
153 struct lttng_evaluation
**evaluation
,
154 const struct notification_thread_state
*state
,
155 const struct channel_state_sample
*previous_sample
,
156 const struct channel_state_sample
*latest_sample
,
157 uint64_t previous_session_consumed_total
,
158 uint64_t latest_session_consumed_total
,
159 struct channel_info
*channel_info
);
161 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
162 const struct lttng_evaluation
*evaluation
,
163 struct notification_client_list
*client_list
,
164 struct notification_thread_state
*state
,
165 uid_t channel_uid
, gid_t channel_gid
);
168 /* session_info API */
170 void session_info_destroy(void *_data
);
172 void session_info_get(struct session_info
*session_info
);
174 void session_info_put(struct session_info
*session_info
);
176 struct session_info
*session_info_create(const char *name
,
177 uid_t uid
, gid_t gid
,
178 struct lttng_session_trigger_list
*trigger_list
,
179 struct cds_lfht
*sessions_ht
);
181 void session_info_add_channel(struct session_info
*session_info
,
182 struct channel_info
*channel_info
);
184 void session_info_remove_channel(struct session_info
*session_info
,
185 struct channel_info
*channel_info
);
187 /* lttng_session_trigger_list API */
189 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
190 const char *session_name
,
191 struct cds_lfht
*session_triggers_ht
);
193 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
194 const struct notification_thread_state
*state
,
195 const char *session_name
);
197 void lttng_session_trigger_list_destroy(
198 struct lttng_session_trigger_list
*list
);
200 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
201 struct lttng_trigger
*trigger
);
204 int client_handle_transmission_status(
205 struct notification_client
*client
,
206 enum client_transmission_status transmission_status
,
207 struct notification_thread_state
*state
);
210 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
);
213 int match_client_socket(struct cds_lfht_node
*node
, const void *key
)
215 /* This double-cast is intended to supress pointer-to-cast warning. */
216 const int socket
= (int) (intptr_t) key
;
217 const struct notification_client
*client
= caa_container_of(node
,
218 struct notification_client
, client_socket_ht_node
);
220 return client
->socket
== socket
;
224 int match_client_id(struct cds_lfht_node
*node
, const void *key
)
226 /* This double-cast is intended to supress pointer-to-cast warning. */
227 const notification_client_id id
= *((notification_client_id
*) key
);
228 const struct notification_client
*client
= caa_container_of(
229 node
, struct notification_client
, client_id_ht_node
);
231 return client
->id
== id
;
235 int match_channel_trigger_list(struct cds_lfht_node
*node
, const void *key
)
237 struct channel_key
*channel_key
= (struct channel_key
*) key
;
238 struct lttng_channel_trigger_list
*trigger_list
;
240 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
241 channel_triggers_ht_node
);
243 return !!((channel_key
->key
== trigger_list
->channel_key
.key
) &&
244 (channel_key
->domain
== trigger_list
->channel_key
.domain
));
248 int match_session_trigger_list(struct cds_lfht_node
*node
, const void *key
)
250 const char *session_name
= (const char *) key
;
251 struct lttng_session_trigger_list
*trigger_list
;
253 trigger_list
= caa_container_of(node
, struct lttng_session_trigger_list
,
254 session_triggers_ht_node
);
256 return !!(strcmp(trigger_list
->session_name
, session_name
) == 0);
260 int match_channel_state_sample(struct cds_lfht_node
*node
, const void *key
)
262 struct channel_key
*channel_key
= (struct channel_key
*) key
;
263 struct channel_state_sample
*sample
;
265 sample
= caa_container_of(node
, struct channel_state_sample
,
266 channel_state_ht_node
);
268 return !!((channel_key
->key
== sample
->key
.key
) &&
269 (channel_key
->domain
== sample
->key
.domain
));
273 int match_channel_info(struct cds_lfht_node
*node
, const void *key
)
275 struct channel_key
*channel_key
= (struct channel_key
*) key
;
276 struct channel_info
*channel_info
;
278 channel_info
= caa_container_of(node
, struct channel_info
,
281 return !!((channel_key
->key
== channel_info
->key
.key
) &&
282 (channel_key
->domain
== channel_info
->key
.domain
));
286 int match_trigger(struct cds_lfht_node
*node
, const void *key
)
288 struct lttng_trigger
*trigger_key
= (struct lttng_trigger
*) key
;
289 struct lttng_trigger_ht_element
*trigger_ht_element
;
291 trigger_ht_element
= caa_container_of(node
, struct lttng_trigger_ht_element
,
294 return !!lttng_trigger_is_equal(trigger_key
, trigger_ht_element
->trigger
);
298 int match_trigger_token(struct cds_lfht_node
*node
, const void *key
)
300 const uint64_t *_key
= key
;
301 struct notification_trigger_tokens_ht_element
*element
;
303 element
= caa_container_of(node
,
304 struct notification_trigger_tokens_ht_element
, node
);
305 return *_key
== element
->token
;
309 int match_client_list_condition(struct cds_lfht_node
*node
, const void *key
)
311 struct lttng_condition
*condition_key
= (struct lttng_condition
*) key
;
312 struct notification_client_list
*client_list
;
313 const struct lttng_condition
*condition
;
315 assert(condition_key
);
317 client_list
= caa_container_of(node
, struct notification_client_list
,
318 notification_trigger_clients_ht_node
);
319 condition
= lttng_trigger_get_const_condition(client_list
->trigger
);
321 return !!lttng_condition_is_equal(condition_key
, condition
);
325 int match_session(struct cds_lfht_node
*node
, const void *key
)
327 const char *name
= key
;
328 struct session_info
*session_info
= caa_container_of(
329 node
, struct session_info
, sessions_ht_node
);
331 return !strcmp(session_info
->name
, name
);
335 const char *notification_command_type_str(
336 enum notification_thread_command_type type
)
339 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
340 return "REGISTER_TRIGGER";
341 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
342 return "UNREGISTER_TRIGGER";
343 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
344 return "ADD_CHANNEL";
345 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
346 return "REMOVE_CHANNEL";
347 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
348 return "SESSION_ROTATION_ONGOING";
349 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
350 return "SESSION_ROTATION_COMPLETED";
351 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
352 return "ADD_TRACER_EVENT_SOURCE";
353 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
354 return "REMOVE_TRACER_EVENT_SOURCE";
355 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
356 return "LIST_TRIGGERS";
357 case NOTIFICATION_COMMAND_TYPE_QUIT
:
359 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
360 return "CLIENT_COMMUNICATION_UPDATE";
367 * Match trigger based on name and credentials only.
368 * Name duplication is NOT allowed for the same uid.
371 int match_trigger_by_name_uid(struct cds_lfht_node
*node
,
376 const char *key_name
;
377 enum lttng_trigger_status status
;
378 const struct lttng_credentials
*key_creds
;
379 const struct lttng_credentials
*node_creds
;
380 const struct lttng_trigger
*trigger_key
=
381 (const struct lttng_trigger
*) key
;
382 const struct lttng_trigger_ht_element
*trigger_ht_element
=
383 caa_container_of(node
,
384 struct lttng_trigger_ht_element
,
387 status
= lttng_trigger_get_name(trigger_ht_element
->trigger
, &name
);
388 assert(status
== LTTNG_TRIGGER_STATUS_OK
);
390 status
= lttng_trigger_get_name(trigger_key
, &key_name
);
391 assert(status
== LTTNG_TRIGGER_STATUS_OK
);
393 /* Compare the names. */
394 if (strcmp(name
, key_name
) != 0) {
398 /* Compare the owners' UIDs. */
399 key_creds
= lttng_trigger_get_credentials(trigger_key
);
400 node_creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
402 match
= lttng_credentials_is_equal_uid(key_creds
, node_creds
);
409 * Hash trigger based on name and credentials only.
412 unsigned long hash_trigger_by_name_uid(const struct lttng_trigger
*trigger
)
414 unsigned long hash
= 0;
415 const struct lttng_credentials
*trigger_creds
;
416 const char *trigger_name
;
417 enum lttng_trigger_status status
;
419 status
= lttng_trigger_get_name(trigger
, &trigger_name
);
420 if (status
== LTTNG_TRIGGER_STATUS_OK
) {
421 hash
= hash_key_str(trigger_name
, lttng_ht_seed
);
424 trigger_creds
= lttng_trigger_get_credentials(trigger
);
425 hash
^= hash_key_ulong((void *) (unsigned long) LTTNG_OPTIONAL_GET(trigger_creds
->uid
),
432 unsigned long hash_channel_key(struct channel_key
*key
)
434 unsigned long key_hash
= hash_key_u64(&key
->key
, lttng_ht_seed
);
435 unsigned long domain_hash
= hash_key_ulong(
436 (void *) (unsigned long) key
->domain
, lttng_ht_seed
);
438 return key_hash
^ domain_hash
;
442 unsigned long hash_client_socket(int socket
)
444 return hash_key_ulong((void *) (unsigned long) socket
, lttng_ht_seed
);
448 unsigned long hash_client_id(notification_client_id id
)
450 return hash_key_u64(&id
, lttng_ht_seed
);
454 * Get the type of object to which a given condition applies. Bindings let
455 * the notification system evaluate a trigger's condition when a given
456 * object's state is updated.
458 * For instance, a condition bound to a channel will be evaluated everytime
459 * the channel's state is changed by a channel monitoring sample.
462 enum lttng_object_type
get_condition_binding_object(
463 const struct lttng_condition
*condition
)
465 switch (lttng_condition_get_type(condition
)) {
466 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
467 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
468 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
469 return LTTNG_OBJECT_TYPE_CHANNEL
;
470 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
471 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
472 return LTTNG_OBJECT_TYPE_SESSION
;
473 case LTTNG_CONDITION_TYPE_EVENT_RULE_HIT
:
474 return LTTNG_OBJECT_TYPE_NONE
;
476 return LTTNG_OBJECT_TYPE_UNKNOWN
;
481 void free_channel_info_rcu(struct rcu_head
*node
)
483 free(caa_container_of(node
, struct channel_info
, rcu_node
));
487 void channel_info_destroy(struct channel_info
*channel_info
)
493 if (channel_info
->session_info
) {
494 session_info_remove_channel(channel_info
->session_info
,
496 session_info_put(channel_info
->session_info
);
498 if (channel_info
->name
) {
499 free(channel_info
->name
);
501 call_rcu(&channel_info
->rcu_node
, free_channel_info_rcu
);
505 void free_session_info_rcu(struct rcu_head
*node
)
507 free(caa_container_of(node
, struct session_info
, rcu_node
));
510 /* Don't call directly, use the ref-counting mechanism. */
512 void session_info_destroy(void *_data
)
514 struct session_info
*session_info
= _data
;
517 assert(session_info
);
518 if (session_info
->channel_infos_ht
) {
519 ret
= cds_lfht_destroy(session_info
->channel_infos_ht
, NULL
);
521 ERR("[notification-thread] Failed to destroy channel information hash table");
524 lttng_session_trigger_list_destroy(session_info
->trigger_list
);
527 cds_lfht_del(session_info
->sessions_ht
,
528 &session_info
->sessions_ht_node
);
530 free(session_info
->name
);
531 call_rcu(&session_info
->rcu_node
, free_session_info_rcu
);
535 void session_info_get(struct session_info
*session_info
)
540 lttng_ref_get(&session_info
->ref
);
544 void session_info_put(struct session_info
*session_info
)
549 lttng_ref_put(&session_info
->ref
);
553 struct session_info
*session_info_create(const char *name
, uid_t uid
, gid_t gid
,
554 struct lttng_session_trigger_list
*trigger_list
,
555 struct cds_lfht
*sessions_ht
)
557 struct session_info
*session_info
;
561 session_info
= zmalloc(sizeof(*session_info
));
565 lttng_ref_init(&session_info
->ref
, session_info_destroy
);
567 session_info
->channel_infos_ht
= cds_lfht_new(DEFAULT_HT_SIZE
,
568 1, 0, CDS_LFHT_AUTO_RESIZE
| CDS_LFHT_ACCOUNTING
, NULL
);
569 if (!session_info
->channel_infos_ht
) {
573 cds_lfht_node_init(&session_info
->sessions_ht_node
);
574 session_info
->name
= strdup(name
);
575 if (!session_info
->name
) {
578 session_info
->uid
= uid
;
579 session_info
->gid
= gid
;
580 session_info
->trigger_list
= trigger_list
;
581 session_info
->sessions_ht
= sessions_ht
;
585 session_info_put(session_info
);
590 void session_info_add_channel(struct session_info
*session_info
,
591 struct channel_info
*channel_info
)
594 cds_lfht_add(session_info
->channel_infos_ht
,
595 hash_channel_key(&channel_info
->key
),
596 &channel_info
->session_info_channels_ht_node
);
601 void session_info_remove_channel(struct session_info
*session_info
,
602 struct channel_info
*channel_info
)
605 cds_lfht_del(session_info
->channel_infos_ht
,
606 &channel_info
->session_info_channels_ht_node
);
611 struct channel_info
*channel_info_create(const char *channel_name
,
612 struct channel_key
*channel_key
, uint64_t channel_capacity
,
613 struct session_info
*session_info
)
615 struct channel_info
*channel_info
= zmalloc(sizeof(*channel_info
));
621 cds_lfht_node_init(&channel_info
->channels_ht_node
);
622 cds_lfht_node_init(&channel_info
->session_info_channels_ht_node
);
623 memcpy(&channel_info
->key
, channel_key
, sizeof(*channel_key
));
624 channel_info
->capacity
= channel_capacity
;
626 channel_info
->name
= strdup(channel_name
);
627 if (!channel_info
->name
) {
632 * Set the references between session and channel infos:
633 * - channel_info holds a strong reference to session_info
634 * - session_info holds a weak reference to channel_info
636 session_info_get(session_info
);
637 session_info_add_channel(session_info
, channel_info
);
638 channel_info
->session_info
= session_info
;
642 channel_info_destroy(channel_info
);
647 bool notification_client_list_get(struct notification_client_list
*list
)
649 return urcu_ref_get_unless_zero(&list
->ref
);
653 void free_notification_client_list_rcu(struct rcu_head
*node
)
655 free(caa_container_of(node
, struct notification_client_list
,
660 void notification_client_list_release(struct urcu_ref
*list_ref
)
662 struct notification_client_list
*list
=
663 container_of(list_ref
, typeof(*list
), ref
);
664 struct notification_client_list_element
*client_list_element
, *tmp
;
666 if (list
->notification_trigger_clients_ht
) {
668 cds_lfht_del(list
->notification_trigger_clients_ht
,
669 &list
->notification_trigger_clients_ht_node
);
671 list
->notification_trigger_clients_ht
= NULL
;
673 cds_list_for_each_entry_safe(client_list_element
, tmp
,
675 free(client_list_element
);
677 pthread_mutex_destroy(&list
->lock
);
678 call_rcu(&list
->rcu_node
, free_notification_client_list_rcu
);
682 struct notification_client_list
*notification_client_list_create(
683 const struct lttng_trigger
*trigger
)
685 struct notification_client_list
*client_list
=
686 zmalloc(sizeof(*client_list
));
691 pthread_mutex_init(&client_list
->lock
, NULL
);
692 urcu_ref_init(&client_list
->ref
);
693 cds_lfht_node_init(&client_list
->notification_trigger_clients_ht_node
);
694 CDS_INIT_LIST_HEAD(&client_list
->list
);
695 client_list
->trigger
= trigger
;
701 void publish_notification_client_list(
702 struct notification_thread_state
*state
,
703 struct notification_client_list
*list
)
705 const struct lttng_condition
*condition
=
706 lttng_trigger_get_const_condition(list
->trigger
);
708 assert(!list
->notification_trigger_clients_ht
);
709 notification_client_list_get(list
);
711 list
->notification_trigger_clients_ht
=
712 state
->notification_trigger_clients_ht
;
715 cds_lfht_add(state
->notification_trigger_clients_ht
,
716 lttng_condition_hash(condition
),
717 &list
->notification_trigger_clients_ht_node
);
722 void notification_client_list_put(struct notification_client_list
*list
)
727 return urcu_ref_put(&list
->ref
, notification_client_list_release
);
730 /* Provides a reference to the returned list. */
732 struct notification_client_list
*get_client_list_from_condition(
733 struct notification_thread_state
*state
,
734 const struct lttng_condition
*condition
)
736 struct cds_lfht_node
*node
;
737 struct cds_lfht_iter iter
;
738 struct notification_client_list
*list
= NULL
;
741 cds_lfht_lookup(state
->notification_trigger_clients_ht
,
742 lttng_condition_hash(condition
),
743 match_client_list_condition
,
746 node
= cds_lfht_iter_get_node(&iter
);
748 list
= container_of(node
, struct notification_client_list
,
749 notification_trigger_clients_ht_node
);
750 list
= notification_client_list_get(list
) ? list
: NULL
;
758 int evaluate_channel_condition_for_client(
759 const struct lttng_condition
*condition
,
760 struct notification_thread_state
*state
,
761 struct lttng_evaluation
**evaluation
,
762 uid_t
*session_uid
, gid_t
*session_gid
)
765 struct cds_lfht_iter iter
;
766 struct cds_lfht_node
*node
;
767 struct channel_info
*channel_info
= NULL
;
768 struct channel_key
*channel_key
= NULL
;
769 struct channel_state_sample
*last_sample
= NULL
;
770 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
774 /* Find the channel associated with the condition. */
775 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
,
776 channel_trigger_list
, channel_triggers_ht_node
) {
777 struct lttng_trigger_list_element
*element
;
779 cds_list_for_each_entry(element
, &channel_trigger_list
->list
, node
) {
780 const struct lttng_condition
*current_condition
=
781 lttng_trigger_get_const_condition(
784 assert(current_condition
);
785 if (!lttng_condition_is_equal(condition
,
786 current_condition
)) {
790 /* Found the trigger, save the channel key. */
791 channel_key
= &channel_trigger_list
->channel_key
;
795 /* The channel key was found stop iteration. */
801 /* No channel found; normal exit. */
802 DBG("[notification-thread] No known channel associated with newly subscribed-to condition");
807 /* Fetch channel info for the matching channel. */
808 cds_lfht_lookup(state
->channels_ht
,
809 hash_channel_key(channel_key
),
813 node
= cds_lfht_iter_get_node(&iter
);
815 channel_info
= caa_container_of(node
, struct channel_info
,
818 /* Retrieve the channel's last sample, if it exists. */
819 cds_lfht_lookup(state
->channel_state_ht
,
820 hash_channel_key(channel_key
),
821 match_channel_state_sample
,
824 node
= cds_lfht_iter_get_node(&iter
);
826 last_sample
= caa_container_of(node
,
827 struct channel_state_sample
,
828 channel_state_ht_node
);
830 /* Nothing to evaluate, no sample was ever taken. Normal exit */
831 DBG("[notification-thread] No channel sample associated with newly subscribed-to condition");
836 ret
= evaluate_buffer_condition(condition
, evaluation
, state
,
838 0, channel_info
->session_info
->consumed_data_size
,
841 WARN("[notification-thread] Fatal error occurred while evaluating a newly subscribed-to condition");
845 *session_uid
= channel_info
->session_info
->uid
;
846 *session_gid
= channel_info
->session_info
->gid
;
853 const char *get_condition_session_name(const struct lttng_condition
*condition
)
855 const char *session_name
= NULL
;
856 enum lttng_condition_status status
;
858 switch (lttng_condition_get_type(condition
)) {
859 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
860 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
861 status
= lttng_condition_buffer_usage_get_session_name(
862 condition
, &session_name
);
864 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
865 status
= lttng_condition_session_consumed_size_get_session_name(
866 condition
, &session_name
);
868 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
869 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
870 status
= lttng_condition_session_rotation_get_session_name(
871 condition
, &session_name
);
876 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
877 ERR("[notification-thread] Failed to retrieve session rotation condition's session name");
885 int evaluate_session_condition_for_client(
886 const struct lttng_condition
*condition
,
887 struct notification_thread_state
*state
,
888 struct lttng_evaluation
**evaluation
,
889 uid_t
*session_uid
, gid_t
*session_gid
)
892 struct cds_lfht_iter iter
;
893 struct cds_lfht_node
*node
;
894 const char *session_name
;
895 struct session_info
*session_info
= NULL
;
898 session_name
= get_condition_session_name(condition
);
900 /* Find the session associated with the trigger. */
901 cds_lfht_lookup(state
->sessions_ht
,
902 hash_key_str(session_name
, lttng_ht_seed
),
906 node
= cds_lfht_iter_get_node(&iter
);
908 DBG("[notification-thread] No known session matching name \"%s\"",
914 session_info
= caa_container_of(node
, struct session_info
,
916 session_info_get(session_info
);
919 * Evaluation is performed in-line here since only one type of
920 * session-bound condition is handled for the moment.
922 switch (lttng_condition_get_type(condition
)) {
923 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
924 if (!session_info
->rotation
.ongoing
) {
926 goto end_session_put
;
929 *evaluation
= lttng_evaluation_session_rotation_ongoing_create(
930 session_info
->rotation
.id
);
933 ERR("[notification-thread] Failed to create session rotation ongoing evaluation for session \"%s\"",
936 goto end_session_put
;
942 goto end_session_put
;
945 *session_uid
= session_info
->uid
;
946 *session_gid
= session_info
->gid
;
949 session_info_put(session_info
);
956 int evaluate_condition_for_client(const struct lttng_trigger
*trigger
,
957 const struct lttng_condition
*condition
,
958 struct notification_client
*client
,
959 struct notification_thread_state
*state
)
962 struct lttng_evaluation
*evaluation
= NULL
;
963 struct notification_client_list client_list
= {
964 .lock
= PTHREAD_MUTEX_INITIALIZER
,
966 struct notification_client_list_element client_list_element
= { 0 };
967 uid_t object_uid
= 0;
968 gid_t object_gid
= 0;
975 switch (get_condition_binding_object(condition
)) {
976 case LTTNG_OBJECT_TYPE_SESSION
:
977 ret
= evaluate_session_condition_for_client(condition
, state
,
978 &evaluation
, &object_uid
, &object_gid
);
980 case LTTNG_OBJECT_TYPE_CHANNEL
:
981 ret
= evaluate_channel_condition_for_client(condition
, state
,
982 &evaluation
, &object_uid
, &object_gid
);
984 case LTTNG_OBJECT_TYPE_NONE
:
985 DBG("[notification-thread] Newly subscribed-to condition not bound to object, nothing to evaluate");
988 case LTTNG_OBJECT_TYPE_UNKNOWN
:
998 /* Evaluation yielded nothing. Normal exit. */
999 DBG("[notification-thread] Newly subscribed-to condition evaluated to false, nothing to report to client");
1005 * Create a temporary client list with the client currently
1008 cds_lfht_node_init(&client_list
.notification_trigger_clients_ht_node
);
1009 CDS_INIT_LIST_HEAD(&client_list
.list
);
1010 client_list
.trigger
= trigger
;
1012 CDS_INIT_LIST_HEAD(&client_list_element
.node
);
1013 client_list_element
.client
= client
;
1014 cds_list_add(&client_list_element
.node
, &client_list
.list
);
1016 /* Send evaluation result to the newly-subscribed client. */
1017 DBG("[notification-thread] Newly subscribed-to condition evaluated to true, notifying client");
1018 ret
= send_evaluation_to_clients(trigger
, evaluation
, &client_list
,
1019 state
, object_uid
, object_gid
);
1026 int notification_thread_client_subscribe(struct notification_client
*client
,
1027 struct lttng_condition
*condition
,
1028 struct notification_thread_state
*state
,
1029 enum lttng_notification_channel_status
*_status
)
1032 struct notification_client_list
*client_list
= NULL
;
1033 struct lttng_condition_list_element
*condition_list_element
= NULL
;
1034 struct notification_client_list_element
*client_list_element
= NULL
;
1035 enum lttng_notification_channel_status status
=
1036 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1039 * Ensure that the client has not already subscribed to this condition
1042 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
, node
) {
1043 if (lttng_condition_is_equal(condition_list_element
->condition
,
1045 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_ALREADY_SUBSCRIBED
;
1050 condition_list_element
= zmalloc(sizeof(*condition_list_element
));
1051 if (!condition_list_element
) {
1055 client_list_element
= zmalloc(sizeof(*client_list_element
));
1056 if (!client_list_element
) {
1062 * Add the newly-subscribed condition to the client's subscription list.
1064 CDS_INIT_LIST_HEAD(&condition_list_element
->node
);
1065 condition_list_element
->condition
= condition
;
1066 cds_list_add(&condition_list_element
->node
, &client
->condition_list
);
1068 client_list
= get_client_list_from_condition(state
, condition
);
1071 * No notification-emiting trigger registered with this
1072 * condition. We don't evaluate the condition right away
1073 * since this trigger is not registered yet.
1075 free(client_list_element
);
1080 * The condition to which the client just subscribed is evaluated
1081 * at this point so that conditions that are already TRUE result
1082 * in a notification being sent out.
1084 * The client_list's trigger is used without locking the list itself.
1085 * This is correct since the list doesn't own the trigger and the
1086 * object is immutable.
1088 if (evaluate_condition_for_client(client_list
->trigger
, condition
,
1090 WARN("[notification-thread] Evaluation of a condition on client subscription failed, aborting.");
1092 free(client_list_element
);
1097 * Add the client to the list of clients interested in a given trigger
1098 * if a "notification" trigger with a corresponding condition was
1101 client_list_element
->client
= client
;
1102 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
1104 pthread_mutex_lock(&client_list
->lock
);
1105 cds_list_add(&client_list_element
->node
, &client_list
->list
);
1106 pthread_mutex_unlock(&client_list
->lock
);
1112 notification_client_list_put(client_list
);
1116 free(condition_list_element
);
1117 free(client_list_element
);
1122 int notification_thread_client_unsubscribe(
1123 struct notification_client
*client
,
1124 struct lttng_condition
*condition
,
1125 struct notification_thread_state
*state
,
1126 enum lttng_notification_channel_status
*_status
)
1128 struct notification_client_list
*client_list
;
1129 struct lttng_condition_list_element
*condition_list_element
,
1131 struct notification_client_list_element
*client_list_element
,
1133 bool condition_found
= false;
1134 enum lttng_notification_channel_status status
=
1135 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1137 /* Remove the condition from the client's condition list. */
1138 cds_list_for_each_entry_safe(condition_list_element
, condition_tmp
,
1139 &client
->condition_list
, node
) {
1140 if (!lttng_condition_is_equal(condition_list_element
->condition
,
1145 cds_list_del(&condition_list_element
->node
);
1147 * The caller may be iterating on the client's conditions to
1148 * tear down a client's connection. In this case, the condition
1149 * will be destroyed at the end.
1151 if (condition
!= condition_list_element
->condition
) {
1152 lttng_condition_destroy(
1153 condition_list_element
->condition
);
1155 free(condition_list_element
);
1156 condition_found
= true;
1160 if (!condition_found
) {
1161 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNKNOWN_CONDITION
;
1166 * Remove the client from the list of clients interested the trigger
1167 * matching the condition.
1169 client_list
= get_client_list_from_condition(state
, condition
);
1174 pthread_mutex_lock(&client_list
->lock
);
1175 cds_list_for_each_entry_safe(client_list_element
, client_tmp
,
1176 &client_list
->list
, node
) {
1177 if (client_list_element
->client
->id
!= client
->id
) {
1180 cds_list_del(&client_list_element
->node
);
1181 free(client_list_element
);
1184 pthread_mutex_unlock(&client_list
->lock
);
1185 notification_client_list_put(client_list
);
1188 lttng_condition_destroy(condition
);
1196 void free_notification_client_rcu(struct rcu_head
*node
)
1198 free(caa_container_of(node
, struct notification_client
, rcu_node
));
1202 void notification_client_destroy(struct notification_client
*client
,
1203 struct notification_thread_state
*state
)
1210 * The client object is not reachable by other threads, no need to lock
1213 if (client
->socket
>= 0) {
1214 (void) lttcomm_close_unix_sock(client
->socket
);
1215 client
->socket
= -1;
1217 client
->communication
.active
= false;
1218 lttng_payload_reset(&client
->communication
.inbound
.payload
);
1219 lttng_payload_reset(&client
->communication
.outbound
.payload
);
1220 pthread_mutex_destroy(&client
->lock
);
1221 call_rcu(&client
->rcu_node
, free_notification_client_rcu
);
1225 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1229 struct notification_client
*get_client_from_socket(int socket
,
1230 struct notification_thread_state
*state
)
1232 struct cds_lfht_iter iter
;
1233 struct cds_lfht_node
*node
;
1234 struct notification_client
*client
= NULL
;
1236 cds_lfht_lookup(state
->client_socket_ht
,
1237 hash_client_socket(socket
),
1238 match_client_socket
,
1239 (void *) (unsigned long) socket
,
1241 node
= cds_lfht_iter_get_node(&iter
);
1246 client
= caa_container_of(node
, struct notification_client
,
1247 client_socket_ht_node
);
1253 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1257 struct notification_client
*get_client_from_id(notification_client_id id
,
1258 struct notification_thread_state
*state
)
1260 struct cds_lfht_iter iter
;
1261 struct cds_lfht_node
*node
;
1262 struct notification_client
*client
= NULL
;
1264 cds_lfht_lookup(state
->client_id_ht
,
1269 node
= cds_lfht_iter_get_node(&iter
);
1274 client
= caa_container_of(node
, struct notification_client
,
1281 bool buffer_usage_condition_applies_to_channel(
1282 const struct lttng_condition
*condition
,
1283 const struct channel_info
*channel_info
)
1285 enum lttng_condition_status status
;
1286 enum lttng_domain_type condition_domain
;
1287 const char *condition_session_name
= NULL
;
1288 const char *condition_channel_name
= NULL
;
1290 status
= lttng_condition_buffer_usage_get_domain_type(condition
,
1292 assert(status
== LTTNG_CONDITION_STATUS_OK
);
1293 if (channel_info
->key
.domain
!= condition_domain
) {
1297 status
= lttng_condition_buffer_usage_get_session_name(
1298 condition
, &condition_session_name
);
1299 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1301 status
= lttng_condition_buffer_usage_get_channel_name(
1302 condition
, &condition_channel_name
);
1303 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_channel_name
);
1305 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1308 if (strcmp(channel_info
->name
, condition_channel_name
)) {
1318 bool session_consumed_size_condition_applies_to_channel(
1319 const struct lttng_condition
*condition
,
1320 const struct channel_info
*channel_info
)
1322 enum lttng_condition_status status
;
1323 const char *condition_session_name
= NULL
;
1325 status
= lttng_condition_session_consumed_size_get_session_name(
1326 condition
, &condition_session_name
);
1327 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1329 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1339 bool trigger_applies_to_channel(const struct lttng_trigger
*trigger
,
1340 const struct channel_info
*channel_info
)
1342 const struct lttng_condition
*condition
;
1343 bool trigger_applies
;
1345 condition
= lttng_trigger_get_const_condition(trigger
);
1350 switch (lttng_condition_get_type(condition
)) {
1351 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
1352 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
1353 trigger_applies
= buffer_usage_condition_applies_to_channel(
1354 condition
, channel_info
);
1356 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
1357 trigger_applies
= session_consumed_size_condition_applies_to_channel(
1358 condition
, channel_info
);
1364 return trigger_applies
;
1370 bool trigger_applies_to_client(struct lttng_trigger
*trigger
,
1371 struct notification_client
*client
)
1373 bool applies
= false;
1374 struct lttng_condition_list_element
*condition_list_element
;
1376 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
,
1378 applies
= lttng_condition_is_equal(
1379 condition_list_element
->condition
,
1380 lttng_trigger_get_condition(trigger
));
1388 /* Must be called with RCU read lock held. */
1390 struct lttng_session_trigger_list
*get_session_trigger_list(
1391 struct notification_thread_state
*state
,
1392 const char *session_name
)
1394 struct lttng_session_trigger_list
*list
= NULL
;
1395 struct cds_lfht_node
*node
;
1396 struct cds_lfht_iter iter
;
1398 cds_lfht_lookup(state
->session_triggers_ht
,
1399 hash_key_str(session_name
, lttng_ht_seed
),
1400 match_session_trigger_list
,
1403 node
= cds_lfht_iter_get_node(&iter
);
1406 * Not an error, the list of triggers applying to that session
1407 * will be initialized when the session is created.
1409 DBG("[notification-thread] No trigger list found for session \"%s\" as it is not yet known to the notification system",
1414 list
= caa_container_of(node
,
1415 struct lttng_session_trigger_list
,
1416 session_triggers_ht_node
);
1422 * Allocate an empty lttng_session_trigger_list for the session named
1425 * No ownership of 'session_name' is assumed by the session trigger list.
1426 * It is the caller's responsability to ensure the session name is alive
1427 * for as long as this list is.
1430 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
1431 const char *session_name
,
1432 struct cds_lfht
*session_triggers_ht
)
1434 struct lttng_session_trigger_list
*list
;
1436 list
= zmalloc(sizeof(*list
));
1440 list
->session_name
= session_name
;
1441 CDS_INIT_LIST_HEAD(&list
->list
);
1442 cds_lfht_node_init(&list
->session_triggers_ht_node
);
1443 list
->session_triggers_ht
= session_triggers_ht
;
1446 /* Publish the list through the session_triggers_ht. */
1447 cds_lfht_add(session_triggers_ht
,
1448 hash_key_str(session_name
, lttng_ht_seed
),
1449 &list
->session_triggers_ht_node
);
1456 void free_session_trigger_list_rcu(struct rcu_head
*node
)
1458 free(caa_container_of(node
, struct lttng_session_trigger_list
,
1463 void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list
*list
)
1465 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1467 /* Empty the list element by element, and then free the list itself. */
1468 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1469 &list
->list
, node
) {
1470 cds_list_del(&trigger_list_element
->node
);
1471 free(trigger_list_element
);
1474 /* Unpublish the list from the session_triggers_ht. */
1475 cds_lfht_del(list
->session_triggers_ht
,
1476 &list
->session_triggers_ht_node
);
1478 call_rcu(&list
->rcu_node
, free_session_trigger_list_rcu
);
1482 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
1483 struct lttng_trigger
*trigger
)
1486 struct lttng_trigger_list_element
*new_element
=
1487 zmalloc(sizeof(*new_element
));
1493 CDS_INIT_LIST_HEAD(&new_element
->node
);
1494 new_element
->trigger
= trigger
;
1495 cds_list_add(&new_element
->node
, &list
->list
);
1501 bool trigger_applies_to_session(const struct lttng_trigger
*trigger
,
1502 const char *session_name
)
1504 bool applies
= false;
1505 const struct lttng_condition
*condition
;
1507 condition
= lttng_trigger_get_const_condition(trigger
);
1508 switch (lttng_condition_get_type(condition
)) {
1509 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1510 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1512 enum lttng_condition_status condition_status
;
1513 const char *condition_session_name
;
1515 condition_status
= lttng_condition_session_rotation_get_session_name(
1516 condition
, &condition_session_name
);
1517 if (condition_status
!= LTTNG_CONDITION_STATUS_OK
) {
1518 ERR("[notification-thread] Failed to retrieve session rotation condition's session name");
1522 assert(condition_session_name
);
1523 applies
= !strcmp(condition_session_name
, session_name
);
1534 * Allocate and initialize an lttng_session_trigger_list which contains
1535 * all triggers that apply to the session named 'session_name'.
1537 * No ownership of 'session_name' is assumed by the session trigger list.
1538 * It is the caller's responsability to ensure the session name is alive
1539 * for as long as this list is.
1542 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
1543 const struct notification_thread_state
*state
,
1544 const char *session_name
)
1546 int trigger_count
= 0;
1547 struct lttng_session_trigger_list
*session_trigger_list
= NULL
;
1548 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1549 struct cds_lfht_iter iter
;
1551 session_trigger_list
= lttng_session_trigger_list_create(session_name
,
1552 state
->session_triggers_ht
);
1554 /* Add all triggers applying to the session named 'session_name'. */
1555 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1559 if (!trigger_applies_to_session(trigger_ht_element
->trigger
,
1564 ret
= lttng_session_trigger_list_add(session_trigger_list
,
1565 trigger_ht_element
->trigger
);
1573 DBG("[notification-thread] Found %i triggers that apply to newly created session",
1575 return session_trigger_list
;
1577 lttng_session_trigger_list_destroy(session_trigger_list
);
1582 struct session_info
*find_or_create_session_info(
1583 struct notification_thread_state
*state
,
1584 const char *name
, uid_t uid
, gid_t gid
)
1586 struct session_info
*session
= NULL
;
1587 struct cds_lfht_node
*node
;
1588 struct cds_lfht_iter iter
;
1589 struct lttng_session_trigger_list
*trigger_list
;
1592 cds_lfht_lookup(state
->sessions_ht
,
1593 hash_key_str(name
, lttng_ht_seed
),
1597 node
= cds_lfht_iter_get_node(&iter
);
1599 DBG("[notification-thread] Found session info of session \"%s\" (uid = %i, gid = %i)",
1601 session
= caa_container_of(node
, struct session_info
,
1603 assert(session
->uid
== uid
);
1604 assert(session
->gid
== gid
);
1605 session_info_get(session
);
1609 trigger_list
= lttng_session_trigger_list_build(state
, name
);
1610 if (!trigger_list
) {
1614 session
= session_info_create(name
, uid
, gid
, trigger_list
,
1615 state
->sessions_ht
);
1617 ERR("[notification-thread] Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
1619 lttng_session_trigger_list_destroy(trigger_list
);
1622 trigger_list
= NULL
;
1624 cds_lfht_add(state
->sessions_ht
, hash_key_str(name
, lttng_ht_seed
),
1625 &session
->sessions_ht_node
);
1631 session_info_put(session
);
1636 int handle_notification_thread_command_add_channel(
1637 struct notification_thread_state
*state
,
1638 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1639 const char *channel_name
, enum lttng_domain_type channel_domain
,
1640 uint64_t channel_key_int
, uint64_t channel_capacity
,
1641 enum lttng_error_code
*cmd_result
)
1643 struct cds_list_head trigger_list
;
1644 struct channel_info
*new_channel_info
= NULL
;
1645 struct channel_key channel_key
= {
1646 .key
= channel_key_int
,
1647 .domain
= channel_domain
,
1649 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
1650 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1651 int trigger_count
= 0;
1652 struct cds_lfht_iter iter
;
1653 struct session_info
*session_info
= NULL
;
1655 DBG("[notification-thread] Adding channel %s from session %s, channel key = %" PRIu64
" in %s domain",
1656 channel_name
, session_name
, channel_key_int
,
1657 channel_domain
== LTTNG_DOMAIN_KERNEL
? "kernel" : "user space");
1659 CDS_INIT_LIST_HEAD(&trigger_list
);
1661 session_info
= find_or_create_session_info(state
, session_name
,
1662 session_uid
, session_gid
);
1663 if (!session_info
) {
1664 /* Allocation error or an internal error occurred. */
1668 new_channel_info
= channel_info_create(channel_name
, &channel_key
,
1669 channel_capacity
, session_info
);
1670 if (!new_channel_info
) {
1675 /* Build a list of all triggers applying to the new channel. */
1676 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1678 struct lttng_trigger_list_element
*new_element
;
1680 if (!trigger_applies_to_channel(trigger_ht_element
->trigger
,
1681 new_channel_info
)) {
1685 new_element
= zmalloc(sizeof(*new_element
));
1690 CDS_INIT_LIST_HEAD(&new_element
->node
);
1691 new_element
->trigger
= trigger_ht_element
->trigger
;
1692 cds_list_add(&new_element
->node
, &trigger_list
);
1697 DBG("[notification-thread] Found %i triggers that apply to newly added channel",
1699 channel_trigger_list
= zmalloc(sizeof(*channel_trigger_list
));
1700 if (!channel_trigger_list
) {
1703 channel_trigger_list
->channel_key
= new_channel_info
->key
;
1704 CDS_INIT_LIST_HEAD(&channel_trigger_list
->list
);
1705 cds_lfht_node_init(&channel_trigger_list
->channel_triggers_ht_node
);
1706 cds_list_splice(&trigger_list
, &channel_trigger_list
->list
);
1709 /* Add channel to the channel_ht which owns the channel_infos. */
1710 cds_lfht_add(state
->channels_ht
,
1711 hash_channel_key(&new_channel_info
->key
),
1712 &new_channel_info
->channels_ht_node
);
1714 * Add the list of triggers associated with this channel to the
1715 * channel_triggers_ht.
1717 cds_lfht_add(state
->channel_triggers_ht
,
1718 hash_channel_key(&new_channel_info
->key
),
1719 &channel_trigger_list
->channel_triggers_ht_node
);
1721 session_info_put(session_info
);
1722 *cmd_result
= LTTNG_OK
;
1725 channel_info_destroy(new_channel_info
);
1726 session_info_put(session_info
);
1731 void free_channel_trigger_list_rcu(struct rcu_head
*node
)
1733 free(caa_container_of(node
, struct lttng_channel_trigger_list
,
1738 void free_channel_state_sample_rcu(struct rcu_head
*node
)
1740 free(caa_container_of(node
, struct channel_state_sample
,
1745 int handle_notification_thread_command_remove_channel(
1746 struct notification_thread_state
*state
,
1747 uint64_t channel_key
, enum lttng_domain_type domain
,
1748 enum lttng_error_code
*cmd_result
)
1750 struct cds_lfht_node
*node
;
1751 struct cds_lfht_iter iter
;
1752 struct lttng_channel_trigger_list
*trigger_list
;
1753 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1754 struct channel_key key
= { .key
= channel_key
, .domain
= domain
};
1755 struct channel_info
*channel_info
;
1757 DBG("[notification-thread] Removing channel key = %" PRIu64
" in %s domain",
1758 channel_key
, domain
== LTTNG_DOMAIN_KERNEL
? "kernel" : "user space");
1762 cds_lfht_lookup(state
->channel_triggers_ht
,
1763 hash_channel_key(&key
),
1764 match_channel_trigger_list
,
1767 node
= cds_lfht_iter_get_node(&iter
);
1769 * There is a severe internal error if we are being asked to remove a
1770 * channel that doesn't exist.
1773 ERR("[notification-thread] Channel being removed is unknown to the notification thread");
1777 /* Free the list of triggers associated with this channel. */
1778 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
1779 channel_triggers_ht_node
);
1780 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1781 &trigger_list
->list
, node
) {
1782 cds_list_del(&trigger_list_element
->node
);
1783 free(trigger_list_element
);
1785 cds_lfht_del(state
->channel_triggers_ht
, node
);
1786 call_rcu(&trigger_list
->rcu_node
, free_channel_trigger_list_rcu
);
1788 /* Free sampled channel state. */
1789 cds_lfht_lookup(state
->channel_state_ht
,
1790 hash_channel_key(&key
),
1791 match_channel_state_sample
,
1794 node
= cds_lfht_iter_get_node(&iter
);
1796 * This is expected to be NULL if the channel is destroyed before we
1797 * received a sample.
1800 struct channel_state_sample
*sample
= caa_container_of(node
,
1801 struct channel_state_sample
,
1802 channel_state_ht_node
);
1804 cds_lfht_del(state
->channel_state_ht
, node
);
1805 call_rcu(&sample
->rcu_node
, free_channel_state_sample_rcu
);
1808 /* Remove the channel from the channels_ht and free it. */
1809 cds_lfht_lookup(state
->channels_ht
,
1810 hash_channel_key(&key
),
1814 node
= cds_lfht_iter_get_node(&iter
);
1816 channel_info
= caa_container_of(node
, struct channel_info
,
1818 cds_lfht_del(state
->channels_ht
, node
);
1819 channel_info_destroy(channel_info
);
1822 *cmd_result
= LTTNG_OK
;
1827 int handle_notification_thread_command_session_rotation(
1828 struct notification_thread_state
*state
,
1829 enum notification_thread_command_type cmd_type
,
1830 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1831 uint64_t trace_archive_chunk_id
,
1832 struct lttng_trace_archive_location
*location
,
1833 enum lttng_error_code
*_cmd_result
)
1836 enum lttng_error_code cmd_result
= LTTNG_OK
;
1837 struct lttng_session_trigger_list
*trigger_list
;
1838 struct lttng_trigger_list_element
*trigger_list_element
;
1839 struct session_info
*session_info
;
1840 const struct lttng_credentials session_creds
= {
1841 .uid
= LTTNG_OPTIONAL_INIT_VALUE(session_uid
),
1842 .gid
= LTTNG_OPTIONAL_INIT_VALUE(session_gid
),
1847 session_info
= find_or_create_session_info(state
, session_name
,
1848 session_uid
, session_gid
);
1849 if (!session_info
) {
1850 /* Allocation error or an internal error occurred. */
1852 cmd_result
= LTTNG_ERR_NOMEM
;
1856 session_info
->rotation
.ongoing
=
1857 cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
;
1858 session_info
->rotation
.id
= trace_archive_chunk_id
;
1859 trigger_list
= get_session_trigger_list(state
, session_name
);
1860 if (!trigger_list
) {
1861 DBG("[notification-thread] No triggers applying to session \"%s\" found",
1866 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
1868 const struct lttng_condition
*condition
;
1869 struct lttng_trigger
*trigger
;
1870 struct notification_client_list
*client_list
;
1871 struct lttng_evaluation
*evaluation
= NULL
;
1872 enum lttng_condition_type condition_type
;
1873 enum action_executor_status executor_status
;
1875 trigger
= trigger_list_element
->trigger
;
1876 condition
= lttng_trigger_get_const_condition(trigger
);
1878 condition_type
= lttng_condition_get_type(condition
);
1880 if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
&&
1881 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1883 } else if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
&&
1884 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
) {
1888 client_list
= get_client_list_from_condition(state
, condition
);
1889 if (cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1890 evaluation
= lttng_evaluation_session_rotation_ongoing_create(
1891 trace_archive_chunk_id
);
1893 evaluation
= lttng_evaluation_session_rotation_completed_create(
1894 trace_archive_chunk_id
, location
);
1898 /* Internal error */
1900 cmd_result
= LTTNG_ERR_UNK
;
1905 * Ownership of `evaluation` transferred to the action executor
1906 * no matter the result.
1908 executor_status
= action_executor_enqueue(state
->executor
,
1909 trigger
, evaluation
, &session_creds
,
1912 switch (executor_status
) {
1913 case ACTION_EXECUTOR_STATUS_OK
:
1915 case ACTION_EXECUTOR_STATUS_ERROR
:
1916 case ACTION_EXECUTOR_STATUS_INVALID
:
1918 * TODO Add trigger identification (name/id) when
1919 * it is added to the API.
1921 ERR("Fatal error occurred while enqueuing action associated with session rotation trigger");
1924 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
1926 * TODO Add trigger identification (name/id) when
1927 * it is added to the API.
1929 * Not a fatal error.
1931 WARN("No space left when enqueuing action associated with session rotation trigger");
1939 notification_client_list_put(client_list
);
1940 if (caa_unlikely(ret
)) {
1945 session_info_put(session_info
);
1946 *_cmd_result
= cmd_result
;
1952 int handle_notification_thread_command_add_tracer_event_source(
1953 struct notification_thread_state
*state
,
1954 int tracer_event_source_fd
,
1955 enum lttng_domain_type domain_type
,
1956 enum lttng_error_code
*_cmd_result
)
1959 enum lttng_error_code cmd_result
= LTTNG_OK
;
1960 struct notification_event_tracer_event_source_element
*element
= NULL
;
1962 element
= zmalloc(sizeof(*element
));
1964 cmd_result
= LTTNG_ERR_NOMEM
;
1969 element
->fd
= tracer_event_source_fd
;
1970 element
->domain
= domain_type
;
1972 cds_list_add(&element
->node
, &state
->tracer_event_sources_list
);
1974 DBG3("[notification-thread] Adding tracer event source fd to poll set: tracer_event_source_fd = %d, domain = '%s'",
1975 tracer_event_source_fd
,
1976 lttng_domain_type_str(domain_type
));
1978 /* Adding the read side pipe to the event poll. */
1979 ret
= lttng_poll_add(&state
->events
, tracer_event_source_fd
, LPOLLIN
| LPOLLERR
);
1981 ERR("[notification-thread] Failed to add tracer event source to poll set: tracer_event_source_fd = %d, domain = '%s'",
1982 tracer_event_source_fd
,
1983 lttng_domain_type_str(element
->domain
));
1984 cds_list_del(&element
->node
);
1989 element
->is_fd_in_poll_set
= true;
1992 *_cmd_result
= cmd_result
;
1997 int handle_notification_thread_command_remove_tracer_event_source(
1998 struct notification_thread_state
*state
,
1999 int tracer_event_source_fd
,
2000 enum lttng_error_code
*_cmd_result
)
2004 enum lttng_error_code cmd_result
= LTTNG_OK
;
2005 struct notification_event_tracer_event_source_element
*source_element
= NULL
, *tmp
;
2007 cds_list_for_each_entry_safe(source_element
, tmp
,
2008 &state
->tracer_event_sources_list
, node
) {
2009 if (source_element
->fd
!= tracer_event_source_fd
) {
2013 DBG("[notification-thread] Removed tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2014 tracer_event_source_fd
,
2015 lttng_domain_type_str(source_element
->domain
));
2016 cds_list_del(&source_element
->node
);
2023 * This is temporarily allowed since the poll activity set is
2024 * not properly cleaned-up for the moment. This is adressed in
2027 source_element
= NULL
;
2031 if (!source_element
->is_fd_in_poll_set
) {
2032 /* Skip the poll set removal. */
2036 DBG3("[notification-thread] Removing tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2037 tracer_event_source_fd
,
2038 lttng_domain_type_str(source_element
->domain
));
2040 /* Removing the fd from the event poll set. */
2041 ret
= lttng_poll_del(&state
->events
, tracer_event_source_fd
);
2043 ERR("[notification-thread] Failed to remove tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2044 tracer_event_source_fd
,
2045 lttng_domain_type_str(source_element
->domain
));
2046 cmd_result
= LTTNG_ERR_FATAL
;
2050 source_element
->is_fd_in_poll_set
= false;
2053 free(source_element
);
2054 *_cmd_result
= cmd_result
;
2058 int handle_notification_thread_remove_tracer_event_source_no_result(
2059 struct notification_thread_state
*state
,
2060 int tracer_event_source_fd
)
2063 enum lttng_error_code cmd_result
;
2065 ret
= handle_notification_thread_command_remove_tracer_event_source(
2066 state
, tracer_event_source_fd
, &cmd_result
);
2071 static int handle_notification_thread_command_list_triggers(
2072 struct notification_thread_handle
*handle
,
2073 struct notification_thread_state
*state
,
2075 struct lttng_triggers
**triggers
,
2076 enum lttng_error_code
*_cmd_result
)
2079 enum lttng_error_code cmd_result
= LTTNG_OK
;
2080 struct cds_lfht_iter iter
;
2081 struct lttng_trigger_ht_element
*trigger_ht_element
;
2082 struct lttng_triggers
*local_triggers
= NULL
;
2083 const struct lttng_credentials
*creds
;
2087 local_triggers
= lttng_triggers_create();
2088 if (!local_triggers
) {
2089 /* Not a fatal error. */
2090 cmd_result
= LTTNG_ERR_NOMEM
;
2094 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
,
2095 trigger_ht_element
, node
) {
2097 * Only return the triggers to which the client has access.
2098 * The root user has visibility over all triggers.
2100 creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
2101 if (client_uid
!= lttng_credentials_get_uid(creds
) && client_uid
!= 0) {
2105 ret
= lttng_triggers_add(local_triggers
,
2106 trigger_ht_element
->trigger
);
2108 /* Not a fatal error. */
2110 cmd_result
= LTTNG_ERR_NOMEM
;
2115 /* Transferring ownership to the caller. */
2116 *triggers
= local_triggers
;
2117 local_triggers
= NULL
;
2121 lttng_triggers_destroy(local_triggers
);
2122 *_cmd_result
= cmd_result
;
2127 bool condition_is_supported(struct lttng_condition
*condition
)
2131 switch (lttng_condition_get_type(condition
)) {
2132 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
2133 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
2136 enum lttng_domain_type domain
;
2138 ret
= lttng_condition_buffer_usage_get_domain_type(condition
,
2142 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2143 is_supported
= true;
2148 * Older kernel tracers don't expose the API to monitor their
2149 * buffers. Therefore, we reject triggers that require that
2150 * mechanism to be available to be evaluated.
2152 * Assume unsupported on error.
2154 is_supported
= kernel_supports_ring_buffer_snapshot_sample_positions() == 1;
2157 case LTTNG_CONDITION_TYPE_EVENT_RULE_HIT
:
2159 const struct lttng_event_rule
*event_rule
;
2160 enum lttng_domain_type domain
;
2161 const enum lttng_condition_status status
=
2162 lttng_condition_event_rule_get_rule(
2163 condition
, &event_rule
);
2165 assert(status
== LTTNG_CONDITION_STATUS_OK
);
2167 domain
= lttng_event_rule_get_domain_type(event_rule
);
2168 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2169 is_supported
= true;
2174 * Older kernel tracers can't emit notification. Therefore, we
2175 * reject triggers that require that mechanism to be available
2178 * Assume unsupported on error.
2180 is_supported
= kernel_supports_event_notifiers() == 1;
2184 is_supported
= true;
2187 return is_supported
;
2190 /* Must be called with RCU read lock held. */
2192 int bind_trigger_to_matching_session(struct lttng_trigger
*trigger
,
2193 struct notification_thread_state
*state
)
2196 const struct lttng_condition
*condition
;
2197 const char *session_name
;
2198 struct lttng_session_trigger_list
*trigger_list
;
2200 condition
= lttng_trigger_get_const_condition(trigger
);
2201 switch (lttng_condition_get_type(condition
)) {
2202 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
2203 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
2205 enum lttng_condition_status status
;
2207 status
= lttng_condition_session_rotation_get_session_name(
2208 condition
, &session_name
);
2209 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
2210 ERR("[notification-thread] Failed to bind trigger to session: unable to get 'session_rotation' condition's session name");
2221 trigger_list
= get_session_trigger_list(state
, session_name
);
2222 if (!trigger_list
) {
2223 DBG("[notification-thread] Unable to bind trigger applying to session \"%s\" as it is not yet known to the notification system",
2229 DBG("[notification-thread] Newly registered trigger bound to session \"%s\"",
2231 ret
= lttng_session_trigger_list_add(trigger_list
, trigger
);
2236 /* Must be called with RCU read lock held. */
2238 int bind_trigger_to_matching_channels(struct lttng_trigger
*trigger
,
2239 struct notification_thread_state
*state
)
2242 struct cds_lfht_node
*node
;
2243 struct cds_lfht_iter iter
;
2244 struct channel_info
*channel
;
2246 cds_lfht_for_each_entry(state
->channels_ht
, &iter
, channel
,
2248 struct lttng_trigger_list_element
*trigger_list_element
;
2249 struct lttng_channel_trigger_list
*trigger_list
;
2250 struct cds_lfht_iter lookup_iter
;
2252 if (!trigger_applies_to_channel(trigger
, channel
)) {
2256 cds_lfht_lookup(state
->channel_triggers_ht
,
2257 hash_channel_key(&channel
->key
),
2258 match_channel_trigger_list
,
2261 node
= cds_lfht_iter_get_node(&lookup_iter
);
2263 trigger_list
= caa_container_of(node
,
2264 struct lttng_channel_trigger_list
,
2265 channel_triggers_ht_node
);
2267 trigger_list_element
= zmalloc(sizeof(*trigger_list_element
));
2268 if (!trigger_list_element
) {
2272 CDS_INIT_LIST_HEAD(&trigger_list_element
->node
);
2273 trigger_list_element
->trigger
= trigger
;
2274 cds_list_add(&trigger_list_element
->node
, &trigger_list
->list
);
2275 DBG("[notification-thread] Newly registered trigger bound to channel \"%s\"",
2283 bool is_trigger_action_notify(const struct lttng_trigger
*trigger
)
2285 bool is_notify
= false;
2286 unsigned int i
, count
;
2287 enum lttng_action_status action_status
;
2288 const struct lttng_action
*action
=
2289 lttng_trigger_get_const_action(trigger
);
2290 enum lttng_action_type action_type
;
2293 action_type
= lttng_action_get_type(action
);
2294 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2297 } else if (action_type
!= LTTNG_ACTION_TYPE_GROUP
) {
2301 action_status
= lttng_action_group_get_count(action
, &count
);
2302 assert(action_status
== LTTNG_ACTION_STATUS_OK
);
2304 for (i
= 0; i
< count
; i
++) {
2305 const struct lttng_action
*inner_action
=
2306 lttng_action_group_get_at_index(
2309 action_type
= lttng_action_get_type(inner_action
);
2310 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2320 static bool trigger_name_taken(struct notification_thread_state
*state
,
2321 const struct lttng_trigger
*trigger
)
2323 struct cds_lfht_iter iter
;
2326 * No duplicata is allowed in the triggers_by_name_uid_ht.
2327 * The match is done against the trigger name and uid.
2329 cds_lfht_lookup(state
->triggers_by_name_uid_ht
,
2330 hash_trigger_by_name_uid(trigger
),
2331 match_trigger_by_name_uid
,
2334 return !!cds_lfht_iter_get_node(&iter
);
2338 enum lttng_error_code
generate_trigger_name(
2339 struct notification_thread_state
*state
,
2340 struct lttng_trigger
*trigger
, const char **name
)
2342 enum lttng_error_code ret_code
= LTTNG_OK
;
2344 enum lttng_trigger_status status
;
2347 const int ret
= lttng_trigger_generate_name(trigger
,
2348 state
->trigger_id
.name_offset
++);
2350 /* The only reason this can fail right now. */
2351 ret_code
= LTTNG_ERR_NOMEM
;
2355 status
= lttng_trigger_get_name(trigger
, name
);
2356 assert(status
== LTTNG_TRIGGER_STATUS_OK
);
2358 taken
= trigger_name_taken(state
, trigger
);
2359 } while (taken
|| state
->trigger_id
.name_offset
== UINT64_MAX
);
2365 * FIXME A client's credentials are not checked when registering a trigger.
2367 * The effects of this are benign since:
2368 * - The client will succeed in registering the trigger, as it is valid,
2369 * - The trigger will, internally, be bound to the channel/session,
2370 * - The notifications will not be sent since the client's credentials
2371 * are checked against the channel at that moment.
2373 * If this function returns a non-zero value, it means something is
2374 * fundamentally broken and the whole subsystem/thread will be torn down.
2376 * If a non-fatal error occurs, just set the cmd_result to the appropriate
2380 int handle_notification_thread_command_register_trigger(
2381 struct notification_thread_state
*state
,
2382 struct lttng_trigger
*trigger
,
2383 enum lttng_error_code
*cmd_result
)
2386 struct lttng_condition
*condition
;
2387 struct notification_client
*client
;
2388 struct notification_client_list
*client_list
= NULL
;
2389 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2390 struct notification_client_list_element
*client_list_element
;
2391 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
= NULL
;
2392 struct cds_lfht_node
*node
;
2393 struct cds_lfht_iter iter
;
2394 const char* trigger_name
;
2395 bool free_trigger
= true;
2396 struct lttng_evaluation
*evaluation
= NULL
;
2397 struct lttng_credentials object_creds
;
2400 enum action_executor_status executor_status
;
2401 const uint64_t trigger_tracer_token
=
2402 state
->trigger_id
.next_tracer_token
++;
2406 /* Set the trigger's tracer token. */
2407 lttng_trigger_set_tracer_token(trigger
, trigger_tracer_token
);
2409 if (lttng_trigger_get_name(trigger
, &trigger_name
) ==
2410 LTTNG_TRIGGER_STATUS_UNSET
) {
2411 const enum lttng_error_code ret_code
= generate_trigger_name(
2412 state
, trigger
, &trigger_name
);
2414 if (ret_code
!= LTTNG_OK
) {
2417 *cmd_result
= ret_code
;
2420 } else if (trigger_name_taken(state
, trigger
)) {
2421 /* Not a fatal error. */
2422 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2427 condition
= lttng_trigger_get_condition(trigger
);
2430 /* Some conditions require tracers to implement a minimal ABI version. */
2431 if (!condition_is_supported(condition
)) {
2432 *cmd_result
= LTTNG_ERR_NOT_SUPPORTED
;
2436 trigger_ht_element
= zmalloc(sizeof(*trigger_ht_element
));
2437 if (!trigger_ht_element
) {
2442 /* Add trigger to the trigger_ht. */
2443 cds_lfht_node_init(&trigger_ht_element
->node
);
2444 cds_lfht_node_init(&trigger_ht_element
->node_by_name_uid
);
2445 trigger_ht_element
->trigger
= trigger
;
2447 node
= cds_lfht_add_unique(state
->triggers_ht
,
2448 lttng_condition_hash(condition
),
2451 &trigger_ht_element
->node
);
2452 if (node
!= &trigger_ht_element
->node
) {
2453 /* Not a fatal error, simply report it to the client. */
2454 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2455 goto error_free_ht_element
;
2458 node
= cds_lfht_add_unique(state
->triggers_by_name_uid_ht
,
2459 hash_trigger_by_name_uid(trigger
),
2460 match_trigger_by_name_uid
,
2462 &trigger_ht_element
->node_by_name_uid
);
2463 if (node
!= &trigger_ht_element
->node_by_name_uid
) {
2464 /* Not a fatal error, simply report it to the client. */
2465 cds_lfht_del(state
->triggers_ht
, &trigger_ht_element
->node
);
2466 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2467 goto error_free_ht_element
;
2470 if (lttng_condition_get_type(condition
) == LTTNG_CONDITION_TYPE_EVENT_RULE_HIT
) {
2471 trigger_tokens_ht_element
= zmalloc(sizeof(*trigger_tokens_ht_element
));
2472 if (!trigger_tokens_ht_element
) {
2475 cds_lfht_del(state
->triggers_ht
,
2476 &trigger_ht_element
->node
);
2477 cds_lfht_del(state
->triggers_by_name_uid_ht
,
2478 &trigger_ht_element
->node_by_name_uid
);
2479 goto error_free_ht_element
;
2482 /* Add trigger token to the trigger_tokens_ht. */
2483 cds_lfht_node_init(&trigger_tokens_ht_element
->node
);
2484 trigger_tokens_ht_element
->token
=
2485 LTTNG_OPTIONAL_GET(trigger
->tracer_token
);
2486 trigger_tokens_ht_element
->trigger
= trigger
;
2488 node
= cds_lfht_add_unique(state
->trigger_tokens_ht
,
2489 hash_key_u64(&trigger_tokens_ht_element
->token
,
2491 match_trigger_token
,
2492 &trigger_tokens_ht_element
->token
,
2493 &trigger_tokens_ht_element
->node
);
2494 if (node
!= &trigger_tokens_ht_element
->node
) {
2495 /* Internal corruption, fatal error. */
2497 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2498 cds_lfht_del(state
->triggers_ht
,
2499 &trigger_ht_element
->node
);
2500 cds_lfht_del(state
->triggers_by_name_uid_ht
,
2501 &trigger_ht_element
->node_by_name_uid
);
2502 goto error_free_ht_element
;
2507 * Ownership of the trigger and of its wrapper was transfered to
2508 * the triggers_ht. Same for token ht element if necessary.
2510 trigger_tokens_ht_element
= NULL
;
2511 trigger_ht_element
= NULL
;
2512 free_trigger
= false;
2515 * The rest only applies to triggers that have a "notify" action.
2516 * It is not skipped as this is the only action type currently
2519 if (is_trigger_action_notify(trigger
)) {
2520 client_list
= notification_client_list_create(trigger
);
2523 goto error_free_ht_element
;
2526 /* Build a list of clients to which this new trigger applies. */
2527 cds_lfht_for_each_entry (state
->client_socket_ht
, &iter
, client
,
2528 client_socket_ht_node
) {
2529 if (!trigger_applies_to_client(trigger
, client
)) {
2533 client_list_element
=
2534 zmalloc(sizeof(*client_list_element
));
2535 if (!client_list_element
) {
2537 goto error_put_client_list
;
2540 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
2541 client_list_element
->client
= client
;
2542 cds_list_add(&client_list_element
->node
,
2543 &client_list
->list
);
2547 * Client list ownership transferred to the
2548 * notification_trigger_clients_ht.
2550 publish_notification_client_list(state
, client_list
);
2553 switch (get_condition_binding_object(condition
)) {
2554 case LTTNG_OBJECT_TYPE_SESSION
:
2555 /* Add the trigger to the list if it matches a known session. */
2556 ret
= bind_trigger_to_matching_session(trigger
, state
);
2558 goto error_put_client_list
;
2561 case LTTNG_OBJECT_TYPE_CHANNEL
:
2563 * Add the trigger to list of triggers bound to the channels
2566 ret
= bind_trigger_to_matching_channels(trigger
, state
);
2568 goto error_put_client_list
;
2571 case LTTNG_OBJECT_TYPE_NONE
:
2574 ERR("Unknown object type on which to bind a newly registered trigger was encountered");
2576 goto error_put_client_list
;
2580 * The new trigger's condition must be evaluated against the current
2583 * In the case of `notify` action, nothing preventing clients from
2584 * subscribing to a condition before the corresponding trigger is
2585 * registered, we have to evaluate this new condition right away.
2587 * At some point, we were waiting for the next "evaluation" (e.g. on
2588 * reception of a channel sample) to evaluate this new condition, but
2591 * The reason it was broken is that waiting for the next sample
2592 * does not allow us to properly handle transitions for edge-triggered
2595 * Consider this example: when we handle a new channel sample, we
2596 * evaluate each conditions twice: once with the previous state, and
2597 * again with the newest state. We then use those two results to
2598 * determine whether a state change happened: a condition was false and
2599 * became true. If a state change happened, we have to notify clients.
2601 * Now, if a client subscribes to a given notification and registers
2602 * a trigger *after* that subscription, we have to make sure the
2603 * condition is evaluated at this point while considering only the
2604 * current state. Otherwise, the next evaluation cycle may only see
2605 * that the evaluations remain the same (true for samples n-1 and n) and
2606 * the client will never know that the condition has been met.
2608 switch (get_condition_binding_object(condition
)) {
2609 case LTTNG_OBJECT_TYPE_SESSION
:
2610 ret
= evaluate_session_condition_for_client(condition
, state
,
2611 &evaluation
, &object_uid
,
2614 case LTTNG_OBJECT_TYPE_CHANNEL
:
2615 ret
= evaluate_channel_condition_for_client(condition
, state
,
2616 &evaluation
, &object_uid
,
2619 case LTTNG_OBJECT_TYPE_NONE
:
2622 case LTTNG_OBJECT_TYPE_UNKNOWN
:
2630 goto error_put_client_list
;
2633 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2634 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2636 DBG("Newly registered trigger's condition evaluated to %s",
2637 evaluation
? "true" : "false");
2639 /* Evaluation yielded nothing. Normal exit. */
2645 * Ownership of `evaluation` transferred to the action executor
2646 * no matter the result.
2648 executor_status
= action_executor_enqueue(state
->executor
, trigger
,
2649 evaluation
, &object_creds
, client_list
);
2651 switch (executor_status
) {
2652 case ACTION_EXECUTOR_STATUS_OK
:
2654 case ACTION_EXECUTOR_STATUS_ERROR
:
2655 case ACTION_EXECUTOR_STATUS_INVALID
:
2657 * TODO Add trigger identification (name/id) when
2658 * it is added to the API.
2660 ERR("Fatal error occurred while enqueuing action associated to newly registered trigger");
2662 goto error_put_client_list
;
2663 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
2665 * TODO Add trigger identification (name/id) when
2666 * it is added to the API.
2668 * Not a fatal error.
2670 WARN("No space left when enqueuing action associated to newly registered trigger");
2678 *cmd_result
= LTTNG_OK
;
2679 DBG("Registered trigger: name = `%s`, tracer token = %" PRIu64
,
2680 trigger_name
, trigger_tracer_token
);
2682 error_put_client_list
:
2683 notification_client_list_put(client_list
);
2685 error_free_ht_element
:
2686 if (trigger_ht_element
) {
2687 /* Delayed removal due to RCU constraint on delete. */
2688 call_rcu(&trigger_ht_element
->rcu_node
,
2689 free_lttng_trigger_ht_element_rcu
);
2692 free(trigger_tokens_ht_element
);
2695 lttng_trigger_destroy(trigger
);
2702 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
)
2704 free(caa_container_of(node
, struct lttng_trigger_ht_element
,
2709 void free_notification_trigger_tokens_ht_element_rcu(struct rcu_head
*node
)
2711 free(caa_container_of(node
, struct notification_trigger_tokens_ht_element
,
2716 int handle_notification_thread_command_unregister_trigger(
2717 struct notification_thread_state
*state
,
2718 const struct lttng_trigger
*trigger
,
2719 enum lttng_error_code
*_cmd_reply
)
2721 struct cds_lfht_iter iter
;
2722 struct cds_lfht_node
*triggers_ht_node
;
2723 struct lttng_channel_trigger_list
*trigger_list
;
2724 struct notification_client_list
*client_list
;
2725 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2726 const struct lttng_condition
*condition
= lttng_trigger_get_const_condition(
2728 enum lttng_error_code cmd_reply
;
2732 cds_lfht_lookup(state
->triggers_ht
,
2733 lttng_condition_hash(condition
),
2737 triggers_ht_node
= cds_lfht_iter_get_node(&iter
);
2738 if (!triggers_ht_node
) {
2739 cmd_reply
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
2742 cmd_reply
= LTTNG_OK
;
2745 /* Remove trigger from channel_triggers_ht. */
2746 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
, trigger_list
,
2747 channel_triggers_ht_node
) {
2748 struct lttng_trigger_list_element
*trigger_element
, *tmp
;
2750 cds_list_for_each_entry_safe(trigger_element
, tmp
,
2751 &trigger_list
->list
, node
) {
2752 if (!lttng_trigger_is_equal(trigger
, trigger_element
->trigger
)) {
2756 DBG("[notification-thread] Removed trigger from channel_triggers_ht");
2757 cds_list_del(&trigger_element
->node
);
2758 /* A trigger can only appear once per channel */
2763 if (lttng_condition_get_type(condition
) ==
2764 LTTNG_CONDITION_TYPE_EVENT_RULE_HIT
) {
2765 struct notification_trigger_tokens_ht_element
2766 *trigger_tokens_ht_element
;
2768 cds_lfht_for_each_entry (state
->trigger_tokens_ht
, &iter
,
2769 trigger_tokens_ht_element
, node
) {
2770 if (!lttng_trigger_is_equal(trigger
,
2771 trigger_tokens_ht_element
->trigger
)) {
2775 DBG("[notification-thread] Removed trigger from tokens_ht");
2776 cds_lfht_del(state
->trigger_tokens_ht
,
2777 &trigger_tokens_ht_element
->node
);
2778 call_rcu(&trigger_tokens_ht_element
->rcu_node
,
2779 free_notification_trigger_tokens_ht_element_rcu
);
2785 if (is_trigger_action_notify(trigger
)) {
2787 * Remove and release the client list from
2788 * notification_trigger_clients_ht.
2790 client_list
= get_client_list_from_condition(state
, condition
);
2791 assert(client_list
);
2793 /* Put new reference and the hashtable's reference. */
2794 notification_client_list_put(client_list
);
2795 notification_client_list_put(client_list
);
2799 /* Remove trigger from triggers_ht. */
2800 trigger_ht_element
= caa_container_of(triggers_ht_node
,
2801 struct lttng_trigger_ht_element
, node
);
2802 cds_lfht_del(state
->triggers_by_name_uid_ht
, &trigger_ht_element
->node_by_name_uid
);
2803 cds_lfht_del(state
->triggers_ht
, triggers_ht_node
);
2805 /* Release the ownership of the trigger. */
2806 lttng_trigger_destroy(trigger_ht_element
->trigger
);
2807 call_rcu(&trigger_ht_element
->rcu_node
, free_lttng_trigger_ht_element_rcu
);
2811 *_cmd_reply
= cmd_reply
;
2816 /* Returns 0 on success, 1 on exit requested, negative value on error. */
2817 int handle_notification_thread_command(
2818 struct notification_thread_handle
*handle
,
2819 struct notification_thread_state
*state
)
2823 struct notification_thread_command
*cmd
;
2825 /* Read the event pipe to put it back into a quiescent state. */
2826 ret
= lttng_read(lttng_pipe_get_readfd(handle
->cmd_queue
.event_pipe
), &counter
,
2828 if (ret
!= sizeof(counter
)) {
2832 pthread_mutex_lock(&handle
->cmd_queue
.lock
);
2833 cmd
= cds_list_first_entry(&handle
->cmd_queue
.list
,
2834 struct notification_thread_command
, cmd_list_node
);
2835 cds_list_del(&cmd
->cmd_list_node
);
2836 pthread_mutex_unlock(&handle
->cmd_queue
.lock
);
2838 DBG("[notification-thread] Received `%s` command",
2839 notification_command_type_str(cmd
->type
));
2840 switch (cmd
->type
) {
2841 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
2842 ret
= handle_notification_thread_command_register_trigger(state
,
2843 cmd
->parameters
.register_trigger
.trigger
,
2846 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
2847 ret
= handle_notification_thread_command_unregister_trigger(
2849 cmd
->parameters
.unregister_trigger
.trigger
,
2852 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
2853 ret
= handle_notification_thread_command_add_channel(
2855 cmd
->parameters
.add_channel
.session
.name
,
2856 cmd
->parameters
.add_channel
.session
.uid
,
2857 cmd
->parameters
.add_channel
.session
.gid
,
2858 cmd
->parameters
.add_channel
.channel
.name
,
2859 cmd
->parameters
.add_channel
.channel
.domain
,
2860 cmd
->parameters
.add_channel
.channel
.key
,
2861 cmd
->parameters
.add_channel
.channel
.capacity
,
2864 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
2865 ret
= handle_notification_thread_command_remove_channel(
2866 state
, cmd
->parameters
.remove_channel
.key
,
2867 cmd
->parameters
.remove_channel
.domain
,
2870 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
2871 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
2872 ret
= handle_notification_thread_command_session_rotation(
2875 cmd
->parameters
.session_rotation
.session_name
,
2876 cmd
->parameters
.session_rotation
.uid
,
2877 cmd
->parameters
.session_rotation
.gid
,
2878 cmd
->parameters
.session_rotation
.trace_archive_chunk_id
,
2879 cmd
->parameters
.session_rotation
.location
,
2882 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
2883 ret
= handle_notification_thread_command_add_tracer_event_source(
2885 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
2886 cmd
->parameters
.tracer_event_source
.domain
,
2889 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
2890 ret
= handle_notification_thread_command_remove_tracer_event_source(
2892 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
2895 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
2897 struct lttng_triggers
*triggers
= NULL
;
2899 ret
= handle_notification_thread_command_list_triggers(
2902 cmd
->parameters
.list_triggers
.uid
,
2905 cmd
->reply
.list_triggers
.triggers
= triggers
;
2909 case NOTIFICATION_COMMAND_TYPE_QUIT
:
2910 cmd
->reply_code
= LTTNG_OK
;
2913 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
2915 const enum client_transmission_status client_status
=
2916 cmd
->parameters
.client_communication_update
2918 const notification_client_id client_id
=
2919 cmd
->parameters
.client_communication_update
.id
;
2920 struct notification_client
*client
;
2923 client
= get_client_from_id(client_id
, state
);
2927 * Client error was probably already picked-up by the
2928 * notification thread or it has disconnected
2929 * gracefully while this command was queued.
2931 DBG("Failed to find notification client to update communication status, client id = %" PRIu64
,
2935 ret
= client_handle_transmission_status(
2936 client
, client_status
, state
);
2942 ERR("[notification-thread] Unknown internal command received");
2950 if (cmd
->is_async
) {
2954 lttng_waiter_wake_up(&cmd
->reply_waiter
);
2958 /* Wake-up and return a fatal error to the calling thread. */
2959 lttng_waiter_wake_up(&cmd
->reply_waiter
);
2960 cmd
->reply_code
= LTTNG_ERR_FATAL
;
2962 /* Indicate a fatal error to the caller. */
2967 int socket_set_non_blocking(int socket
)
2971 /* Set the pipe as non-blocking. */
2972 ret
= fcntl(socket
, F_GETFL
, 0);
2974 PERROR("fcntl get socket flags");
2979 ret
= fcntl(socket
, F_SETFL
, flags
| O_NONBLOCK
);
2981 PERROR("fcntl set O_NONBLOCK socket flag");
2984 DBG("Client socket (fd = %i) set as non-blocking", socket
);
2990 int client_reset_inbound_state(struct notification_client
*client
)
2995 lttng_payload_clear(&client
->communication
.inbound
.payload
);
2997 client
->communication
.inbound
.bytes_to_receive
=
2998 sizeof(struct lttng_notification_channel_message
);
2999 client
->communication
.inbound
.msg_type
=
3000 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
;
3001 LTTNG_SOCK_SET_UID_CRED(&client
->communication
.inbound
.creds
, -1);
3002 LTTNG_SOCK_SET_GID_CRED(&client
->communication
.inbound
.creds
, -1);
3003 ret
= lttng_dynamic_buffer_set_size(
3004 &client
->communication
.inbound
.payload
.buffer
,
3005 client
->communication
.inbound
.bytes_to_receive
);
3010 int handle_notification_thread_client_connect(
3011 struct notification_thread_state
*state
)
3014 struct notification_client
*client
;
3016 DBG("[notification-thread] Handling new notification channel client connection");
3018 client
= zmalloc(sizeof(*client
));
3025 pthread_mutex_init(&client
->lock
, NULL
);
3026 client
->id
= state
->next_notification_client_id
++;
3027 CDS_INIT_LIST_HEAD(&client
->condition_list
);
3028 lttng_payload_init(&client
->communication
.inbound
.payload
);
3029 lttng_payload_init(&client
->communication
.outbound
.payload
);
3030 client
->communication
.inbound
.expect_creds
= true;
3032 ret
= client_reset_inbound_state(client
);
3034 ERR("[notification-thread] Failed to reset client communication's inbound state");
3039 ret
= lttcomm_accept_unix_sock(state
->notification_channel_socket
);
3041 ERR("[notification-thread] Failed to accept new notification channel client connection");
3046 client
->socket
= ret
;
3048 ret
= socket_set_non_blocking(client
->socket
);
3050 ERR("[notification-thread] Failed to set new notification channel client connection socket as non-blocking");
3054 ret
= lttcomm_setsockopt_creds_unix_sock(client
->socket
);
3056 ERR("[notification-thread] Failed to set socket options on new notification channel client socket");
3061 ret
= lttng_poll_add(&state
->events
, client
->socket
,
3062 LPOLLIN
| LPOLLERR
|
3063 LPOLLHUP
| LPOLLRDHUP
);
3065 ERR("[notification-thread] Failed to add notification channel client socket to poll set");
3069 DBG("[notification-thread] Added new notification channel client socket (%i) to poll set",
3073 cds_lfht_add(state
->client_socket_ht
,
3074 hash_client_socket(client
->socket
),
3075 &client
->client_socket_ht_node
);
3076 cds_lfht_add(state
->client_id_ht
,
3077 hash_client_id(client
->id
),
3078 &client
->client_id_ht_node
);
3084 notification_client_destroy(client
, state
);
3089 * RCU read-lock must be held by the caller.
3090 * Client lock must _not_ be held by the caller.
3093 int notification_thread_client_disconnect(
3094 struct notification_client
*client
,
3095 struct notification_thread_state
*state
)
3098 struct lttng_condition_list_element
*condition_list_element
, *tmp
;
3100 /* Acquire the client lock to disable its communication atomically. */
3101 pthread_mutex_lock(&client
->lock
);
3102 client
->communication
.active
= false;
3103 cds_lfht_del(state
->client_socket_ht
, &client
->client_socket_ht_node
);
3104 cds_lfht_del(state
->client_id_ht
, &client
->client_id_ht_node
);
3105 pthread_mutex_unlock(&client
->lock
);
3107 ret
= lttng_poll_del(&state
->events
, client
->socket
);
3109 ERR("[notification-thread] Failed to remove client socket %d from poll set",
3113 /* Release all conditions to which the client was subscribed. */
3114 cds_list_for_each_entry_safe(condition_list_element
, tmp
,
3115 &client
->condition_list
, node
) {
3116 (void) notification_thread_client_unsubscribe(client
,
3117 condition_list_element
->condition
, state
, NULL
);
3121 * Client no longer accessible to other threads (through the
3124 notification_client_destroy(client
, state
);
3128 int handle_notification_thread_client_disconnect(
3129 int client_socket
, struct notification_thread_state
*state
)
3132 struct notification_client
*client
;
3135 DBG("[notification-thread] Closing client connection (socket fd = %i)",
3137 client
= get_client_from_socket(client_socket
, state
);
3139 /* Internal state corruption, fatal error. */
3140 ERR("[notification-thread] Unable to find client (socket fd = %i)",
3146 ret
= notification_thread_client_disconnect(client
, state
);
3152 int handle_notification_thread_client_disconnect_all(
3153 struct notification_thread_state
*state
)
3155 struct cds_lfht_iter iter
;
3156 struct notification_client
*client
;
3157 bool error_encoutered
= false;
3160 DBG("[notification-thread] Closing all client connections");
3161 cds_lfht_for_each_entry(state
->client_socket_ht
, &iter
, client
,
3162 client_socket_ht_node
) {
3165 ret
= notification_thread_client_disconnect(
3168 error_encoutered
= true;
3172 return error_encoutered
? 1 : 0;
3175 int handle_notification_thread_trigger_unregister_all(
3176 struct notification_thread_state
*state
)
3178 bool error_occurred
= false;
3179 struct cds_lfht_iter iter
;
3180 struct lttng_trigger_ht_element
*trigger_ht_element
;
3183 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
3185 int ret
= handle_notification_thread_command_unregister_trigger(
3186 state
, trigger_ht_element
->trigger
, NULL
);
3188 error_occurred
= true;
3192 return error_occurred
? -1 : 0;
3196 int client_handle_transmission_status(
3197 struct notification_client
*client
,
3198 enum client_transmission_status transmission_status
,
3199 struct notification_thread_state
*state
)
3203 switch (transmission_status
) {
3204 case CLIENT_TRANSMISSION_STATUS_COMPLETE
:
3205 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3206 CLIENT_POLL_MASK_IN
);
3212 case CLIENT_TRANSMISSION_STATUS_QUEUED
:
3214 * We want to be notified whenever there is buffer space
3215 * available to send the rest of the payload.
3217 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3218 CLIENT_POLL_MASK_IN_OUT
);
3223 case CLIENT_TRANSMISSION_STATUS_FAIL
:
3224 ret
= notification_thread_client_disconnect(client
, state
);
3229 case CLIENT_TRANSMISSION_STATUS_ERROR
:
3239 /* Client lock must be acquired by caller. */
3241 enum client_transmission_status
client_flush_outgoing_queue(
3242 struct notification_client
*client
)
3245 size_t to_send_count
;
3246 enum client_transmission_status status
;
3247 struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3248 &client
->communication
.outbound
.payload
, 0, -1);
3249 const int fds_to_send_count
=
3250 lttng_payload_view_get_fd_handle_count(&pv
);
3252 ASSERT_LOCKED(client
->lock
);
3254 if (!client
->communication
.active
) {
3255 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3259 if (pv
.buffer
.size
== 0) {
3261 * If both data and fds are equal to zero, we are in an invalid
3264 assert(fds_to_send_count
!= 0);
3269 to_send_count
= pv
.buffer
.size
;
3270 DBG("[notification-thread] Flushing client (socket fd = %i) outgoing queue",
3273 ret
= lttcomm_send_unix_sock_non_block(client
->socket
,
3276 if ((ret
>= 0 && ret
< to_send_count
)) {
3277 DBG("[notification-thread] Client (socket fd = %i) outgoing queue could not be completely flushed",
3279 to_send_count
-= max(ret
, 0);
3281 memmove(client
->communication
.outbound
.payload
.buffer
.data
,
3283 pv
.buffer
.size
- to_send_count
,
3285 ret
= lttng_dynamic_buffer_set_size(
3286 &client
->communication
.outbound
.payload
.buffer
,
3292 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3294 } else if (ret
< 0) {
3295 /* Generic error, disable the client's communication. */
3296 ERR("[notification-thread] Failed to flush outgoing queue, disconnecting client (socket fd = %i)",
3298 client
->communication
.active
= false;
3299 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3303 * No error and flushed the queue completely.
3305 * The payload buffer size is used later to
3306 * check if there is notifications queued. So albeit that the
3307 * direct caller knows that the transmission is complete, we
3308 * need to set the buffer size to zero.
3310 ret
= lttng_dynamic_buffer_set_size(
3311 &client
->communication
.outbound
.payload
.buffer
, 0);
3318 /* No fds to send, transmission is complete. */
3319 if (fds_to_send_count
== 0) {
3320 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3324 ret
= lttcomm_send_payload_view_fds_unix_sock_non_block(
3325 client
->socket
, &pv
);
3327 /* Generic error, disable the client's communication. */
3328 ERR("[notification-thread] Failed to flush outgoing fds queue, disconnecting client (socket fd = %i)",
3330 client
->communication
.active
= false;
3331 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3333 } else if (ret
== 0) {
3334 /* Nothing could be sent. */
3335 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3337 /* Fd passing is an all or nothing kind of thing. */
3338 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3340 * The payload _fd_array count is used later to
3341 * check if there is notifications queued. So although the
3342 * direct caller knows that the transmission is complete, we
3343 * need to clear the _fd_array for the queuing check.
3345 lttng_dynamic_pointer_array_clear(
3346 &client
->communication
.outbound
.payload
3351 if (status
== CLIENT_TRANSMISSION_STATUS_COMPLETE
) {
3352 client
->communication
.outbound
.queued_command_reply
= false;
3353 client
->communication
.outbound
.dropped_notification
= false;
3354 lttng_payload_clear(&client
->communication
.outbound
.payload
);
3359 return CLIENT_TRANSMISSION_STATUS_ERROR
;
3363 bool client_has_outbound_data_left(
3364 const struct notification_client
*client
)
3366 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3367 &client
->communication
.outbound
.payload
, 0, -1);
3368 const bool has_data
= pv
.buffer
.size
!= 0;
3369 const bool has_fds
= lttng_payload_view_get_fd_handle_count(&pv
);
3371 return has_data
|| has_fds
;
3374 /* Client lock must _not_ be held by the caller. */
3376 int client_send_command_reply(struct notification_client
*client
,
3377 struct notification_thread_state
*state
,
3378 enum lttng_notification_channel_status status
)
3381 struct lttng_notification_channel_command_reply reply
= {
3382 .status
= (int8_t) status
,
3384 struct lttng_notification_channel_message msg
= {
3385 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY
,
3386 .size
= sizeof(reply
),
3388 char buffer
[sizeof(msg
) + sizeof(reply
)];
3389 enum client_transmission_status transmission_status
;
3391 memcpy(buffer
, &msg
, sizeof(msg
));
3392 memcpy(buffer
+ sizeof(msg
), &reply
, sizeof(reply
));
3393 DBG("[notification-thread] Send command reply (%i)", (int) status
);
3395 pthread_mutex_lock(&client
->lock
);
3396 if (client
->communication
.outbound
.queued_command_reply
) {
3397 /* Protocol error. */
3401 /* Enqueue buffer to outgoing queue and flush it. */
3402 ret
= lttng_dynamic_buffer_append(
3403 &client
->communication
.outbound
.payload
.buffer
,
3404 buffer
, sizeof(buffer
));
3409 transmission_status
= client_flush_outgoing_queue(client
);
3411 if (client_has_outbound_data_left(client
)) {
3412 /* Queue could not be emptied. */
3413 client
->communication
.outbound
.queued_command_reply
= true;
3416 pthread_mutex_unlock(&client
->lock
);
3417 ret
= client_handle_transmission_status(
3418 client
, transmission_status
, state
);
3425 pthread_mutex_unlock(&client
->lock
);
3431 int client_handle_message_unknown(struct notification_client
*client
,
3432 struct notification_thread_state
*state
)
3436 * Receiving message header. The function will be called again
3437 * once the rest of the message as been received and can be
3440 const struct lttng_notification_channel_message
*msg
;
3442 assert(sizeof(*msg
) == client
->communication
.inbound
.payload
.buffer
.size
);
3443 msg
= (const struct lttng_notification_channel_message
*)
3444 client
->communication
.inbound
.payload
.buffer
.data
;
3446 if (msg
->size
== 0 ||
3447 msg
->size
> DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE
) {
3448 ERR("[notification-thread] Invalid notification channel message: length = %u",
3454 switch (msg
->type
) {
3455 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3456 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3457 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3461 ERR("[notification-thread] Invalid notification channel message: unexpected message type");
3465 client
->communication
.inbound
.bytes_to_receive
= msg
->size
;
3466 client
->communication
.inbound
.fds_to_receive
= msg
->fds
;
3467 client
->communication
.inbound
.msg_type
=
3468 (enum lttng_notification_channel_message_type
) msg
->type
;
3469 ret
= lttng_dynamic_buffer_set_size(
3470 &client
->communication
.inbound
.payload
.buffer
, msg
->size
);
3472 /* msg is not valid anymore due to lttng_dynamic_buffer_set_size. */
3479 int client_handle_message_handshake(struct notification_client
*client
,
3480 struct notification_thread_state
*state
)
3483 struct lttng_notification_channel_command_handshake
*handshake_client
;
3484 const struct lttng_notification_channel_command_handshake handshake_reply
= {
3485 .major
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
,
3486 .minor
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR
,
3488 const struct lttng_notification_channel_message msg_header
= {
3489 .type
= LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
,
3490 .size
= sizeof(handshake_reply
),
3492 enum lttng_notification_channel_status status
=
3493 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3494 char send_buffer
[sizeof(msg_header
) + sizeof(handshake_reply
)];
3496 memcpy(send_buffer
, &msg_header
, sizeof(msg_header
));
3497 memcpy(send_buffer
+ sizeof(msg_header
), &handshake_reply
,
3498 sizeof(handshake_reply
));
3501 (struct lttng_notification_channel_command_handshake
*)
3502 client
->communication
.inbound
.payload
.buffer
3504 client
->major
= handshake_client
->major
;
3505 client
->minor
= handshake_client
->minor
;
3506 if (!client
->communication
.inbound
.creds_received
) {
3507 ERR("[notification-thread] No credentials received from client");
3512 client
->uid
= LTTNG_SOCK_GET_UID_CRED(
3513 &client
->communication
.inbound
.creds
);
3514 client
->gid
= LTTNG_SOCK_GET_GID_CRED(
3515 &client
->communication
.inbound
.creds
);
3516 DBG("[notification-thread] Received handshake from client (uid = %u, gid = %u) with version %i.%i",
3517 client
->uid
, client
->gid
, (int) client
->major
,
3518 (int) client
->minor
);
3520 if (handshake_client
->major
!=
3521 LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
) {
3522 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION
;
3525 pthread_mutex_lock(&client
->lock
);
3526 /* Outgoing queue will be flushed when the command reply is sent. */
3527 ret
= lttng_dynamic_buffer_append(
3528 &client
->communication
.outbound
.payload
.buffer
, send_buffer
,
3529 sizeof(send_buffer
));
3531 ERR("[notification-thread] Failed to send protocol version to notification channel client");
3535 client
->validated
= true;
3536 client
->communication
.active
= true;
3537 pthread_mutex_unlock(&client
->lock
);
3539 /* Set reception state to receive the next message header. */
3540 ret
= client_reset_inbound_state(client
);
3542 ERR("[notification-thread] Failed to reset client communication's inbound state");
3546 /* Flushes the outgoing queue. */
3547 ret
= client_send_command_reply(client
, state
, status
);
3549 ERR("[notification-thread] Failed to send reply to notification channel client");
3555 pthread_mutex_unlock(&client
->lock
);
3561 int client_handle_message_subscription(
3562 struct notification_client
*client
,
3563 enum lttng_notification_channel_message_type msg_type
,
3564 struct notification_thread_state
*state
)
3567 struct lttng_condition
*condition
;
3568 enum lttng_notification_channel_status status
=
3569 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3570 struct lttng_payload_view condition_view
=
3571 lttng_payload_view_from_payload(
3572 &client
->communication
.inbound
.payload
,
3574 size_t expected_condition_size
;
3577 * No need to lock client to sample the inbound state as the only
3578 * other thread accessing clients (action executor) only uses the
3581 expected_condition_size
= client
->communication
.inbound
.payload
.buffer
.size
;
3582 ret
= lttng_condition_create_from_payload(&condition_view
, &condition
);
3583 if (ret
!= expected_condition_size
) {
3584 ERR("[notification-thread] Malformed condition received from client");
3588 if (msg_type
== LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
) {
3589 ret
= notification_thread_client_subscribe(
3590 client
, condition
, state
, &status
);
3592 ret
= notification_thread_client_unsubscribe(
3593 client
, condition
, state
, &status
);
3600 /* Set reception state to receive the next message header. */
3601 ret
= client_reset_inbound_state(client
);
3603 ERR("[notification-thread] Failed to reset client communication's inbound state");
3607 ret
= client_send_command_reply(client
, state
, status
);
3609 ERR("[notification-thread] Failed to send reply to notification channel client");
3618 int client_dispatch_message(struct notification_client
*client
,
3619 struct notification_thread_state
*state
)
3623 if (client
->communication
.inbound
.msg_type
!=
3624 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
&&
3625 client
->communication
.inbound
.msg_type
!=
3626 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
&&
3627 !client
->validated
) {
3628 WARN("[notification-thread] client attempted a command before handshake");
3633 switch (client
->communication
.inbound
.msg_type
) {
3634 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
:
3636 ret
= client_handle_message_unknown(client
, state
);
3639 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3641 ret
= client_handle_message_handshake(client
, state
);
3644 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3645 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3647 ret
= client_handle_message_subscription(client
,
3648 client
->communication
.inbound
.msg_type
, state
);
3658 /* Incoming data from client. */
3659 int handle_notification_thread_client_in(
3660 struct notification_thread_state
*state
, int socket
)
3663 struct notification_client
*client
;
3668 client
= get_client_from_socket(socket
, state
);
3670 /* Internal error, abort. */
3675 offset
= client
->communication
.inbound
.payload
.buffer
.size
-
3676 client
->communication
.inbound
.bytes_to_receive
;
3677 if (client
->communication
.inbound
.expect_creds
) {
3678 recv_ret
= lttcomm_recv_creds_unix_sock(socket
,
3679 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
3680 client
->communication
.inbound
.bytes_to_receive
,
3681 &client
->communication
.inbound
.creds
);
3683 client
->communication
.inbound
.expect_creds
= false;
3684 client
->communication
.inbound
.creds_received
= true;
3687 recv_ret
= lttcomm_recv_unix_sock_non_block(socket
,
3688 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
3689 client
->communication
.inbound
.bytes_to_receive
);
3691 if (recv_ret
>= 0) {
3692 client
->communication
.inbound
.bytes_to_receive
-= recv_ret
;
3694 goto error_disconnect_client
;
3697 if (client
->communication
.inbound
.bytes_to_receive
!= 0) {
3698 /* Message incomplete wait for more data. */
3703 assert(client
->communication
.inbound
.bytes_to_receive
== 0);
3706 if (client
->communication
.inbound
.fds_to_receive
!= 0) {
3707 ret
= lttcomm_recv_payload_fds_unix_sock_non_block(
3709 client
->communication
.inbound
.fds_to_receive
,
3710 &client
->communication
.inbound
.payload
);
3713 * Fds received. non blocking fds passing is all
3716 ssize_t expected_size
;
3718 expected_size
= sizeof(int) *
3719 client
->communication
.inbound
3721 assert(ret
== expected_size
);
3722 client
->communication
.inbound
.fds_to_receive
= 0;
3723 } else if (ret
== 0) {
3724 /* Received nothing. */
3728 goto error_disconnect_client
;
3732 /* At this point the message is complete.*/
3733 assert(client
->communication
.inbound
.bytes_to_receive
== 0 &&
3734 client
->communication
.inbound
.fds_to_receive
== 0);
3735 ret
= client_dispatch_message(client
, state
);
3738 * Only returns an error if this client must be
3741 goto error_disconnect_client
;
3748 error_disconnect_client
:
3749 ret
= notification_thread_client_disconnect(client
, state
);
3753 /* Client ready to receive outgoing data. */
3754 int handle_notification_thread_client_out(
3755 struct notification_thread_state
*state
, int socket
)
3758 struct notification_client
*client
;
3759 enum client_transmission_status transmission_status
;
3762 client
= get_client_from_socket(socket
, state
);
3764 /* Internal error, abort. */
3769 pthread_mutex_lock(&client
->lock
);
3770 transmission_status
= client_flush_outgoing_queue(client
);
3771 pthread_mutex_unlock(&client
->lock
);
3773 ret
= client_handle_transmission_status(
3774 client
, transmission_status
, state
);
3784 bool evaluate_buffer_usage_condition(const struct lttng_condition
*condition
,
3785 const struct channel_state_sample
*sample
,
3786 uint64_t buffer_capacity
)
3788 bool result
= false;
3790 enum lttng_condition_type condition_type
;
3791 const struct lttng_condition_buffer_usage
*use_condition
= container_of(
3792 condition
, struct lttng_condition_buffer_usage
,
3795 if (use_condition
->threshold_bytes
.set
) {
3796 threshold
= use_condition
->threshold_bytes
.value
;
3799 * Threshold was expressed as a ratio.
3801 * TODO the threshold (in bytes) of conditions expressed
3802 * as a ratio of total buffer size could be cached to
3803 * forego this double-multiplication or it could be performed
3804 * as fixed-point math.
3806 * Note that caching should accommodates the case where the
3807 * condition applies to multiple channels (i.e. don't assume
3808 * that all channels matching my_chann* have the same size...)
3810 threshold
= (uint64_t) (use_condition
->threshold_ratio
.value
*
3811 (double) buffer_capacity
);
3814 condition_type
= lttng_condition_get_type(condition
);
3815 if (condition_type
== LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
) {
3816 DBG("[notification-thread] Low buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
3817 threshold
, sample
->highest_usage
);
3820 * The low condition should only be triggered once _all_ of the
3821 * streams in a channel have gone below the "low" threshold.
3823 if (sample
->highest_usage
<= threshold
) {
3827 DBG("[notification-thread] High buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
3828 threshold
, sample
->highest_usage
);
3831 * For high buffer usage scenarios, we want to trigger whenever
3832 * _any_ of the streams has reached the "high" threshold.
3834 if (sample
->highest_usage
>= threshold
) {
3843 bool evaluate_session_consumed_size_condition(
3844 const struct lttng_condition
*condition
,
3845 uint64_t session_consumed_size
)
3848 const struct lttng_condition_session_consumed_size
*size_condition
=
3849 container_of(condition
,
3850 struct lttng_condition_session_consumed_size
,
3853 threshold
= size_condition
->consumed_threshold_bytes
.value
;
3854 DBG("[notification-thread] Session consumed size condition being evaluated: threshold = %" PRIu64
", current size = %" PRIu64
,
3855 threshold
, session_consumed_size
);
3856 return session_consumed_size
>= threshold
;
3860 int evaluate_buffer_condition(const struct lttng_condition
*condition
,
3861 struct lttng_evaluation
**evaluation
,
3862 const struct notification_thread_state
*state
,
3863 const struct channel_state_sample
*previous_sample
,
3864 const struct channel_state_sample
*latest_sample
,
3865 uint64_t previous_session_consumed_total
,
3866 uint64_t latest_session_consumed_total
,
3867 struct channel_info
*channel_info
)
3870 enum lttng_condition_type condition_type
;
3871 const bool previous_sample_available
= !!previous_sample
;
3872 bool previous_sample_result
= false;
3873 bool latest_sample_result
;
3875 condition_type
= lttng_condition_get_type(condition
);
3877 switch (condition_type
) {
3878 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
3879 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
3880 if (caa_likely(previous_sample_available
)) {
3881 previous_sample_result
=
3882 evaluate_buffer_usage_condition(condition
,
3883 previous_sample
, channel_info
->capacity
);
3885 latest_sample_result
= evaluate_buffer_usage_condition(
3886 condition
, latest_sample
,
3887 channel_info
->capacity
);
3889 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
3890 if (caa_likely(previous_sample_available
)) {
3891 previous_sample_result
=
3892 evaluate_session_consumed_size_condition(
3894 previous_session_consumed_total
);
3896 latest_sample_result
=
3897 evaluate_session_consumed_size_condition(
3899 latest_session_consumed_total
);
3902 /* Unknown condition type; internal error. */
3906 if (!latest_sample_result
||
3907 (previous_sample_result
== latest_sample_result
)) {
3909 * Only trigger on a condition evaluation transition.
3911 * NOTE: This edge-triggered logic may not be appropriate for
3912 * future condition types.
3917 if (!evaluation
|| !latest_sample_result
) {
3921 switch (condition_type
) {
3922 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
3923 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
3924 *evaluation
= lttng_evaluation_buffer_usage_create(
3926 latest_sample
->highest_usage
,
3927 channel_info
->capacity
);
3929 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
3930 *evaluation
= lttng_evaluation_session_consumed_size_create(
3931 latest_session_consumed_total
);
3946 int client_notification_overflow(struct notification_client
*client
)
3949 const struct lttng_notification_channel_message msg
= {
3950 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED
,
3953 ASSERT_LOCKED(client
->lock
);
3955 DBG("Dropping notification addressed to client (socket fd = %i)",
3957 if (client
->communication
.outbound
.dropped_notification
) {
3959 * The client already has a "notification dropped" message
3960 * in its outgoing queue. Nothing to do since all
3961 * of those messages are coalesced.
3966 client
->communication
.outbound
.dropped_notification
= true;
3967 ret
= lttng_dynamic_buffer_append(
3968 &client
->communication
.outbound
.payload
.buffer
, &msg
,
3971 PERROR("Failed to enqueue \"dropped notification\" message in client's (socket fd = %i) outgoing queue",
3978 static int client_handle_transmission_status_wrapper(
3979 struct notification_client
*client
,
3980 enum client_transmission_status status
,
3983 return client_handle_transmission_status(client
, status
,
3984 (struct notification_thread_state
*) user_data
);
3988 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
3989 const struct lttng_evaluation
*evaluation
,
3990 struct notification_client_list
* client_list
,
3991 struct notification_thread_state
*state
,
3992 uid_t object_uid
, gid_t object_gid
)
3994 const struct lttng_credentials creds
= {
3995 .uid
= LTTNG_OPTIONAL_INIT_VALUE(object_uid
),
3996 .gid
= LTTNG_OPTIONAL_INIT_VALUE(object_gid
),
3999 return notification_client_list_send_evaluation(client_list
,
4000 lttng_trigger_get_const_condition(trigger
), evaluation
,
4001 lttng_trigger_get_credentials(trigger
),
4003 client_handle_transmission_status_wrapper
, state
);
4007 * Permission checks relative to notification channel clients are performed
4008 * here. Notice how object, client, and trigger credentials are involved in
4011 * The `object` credentials are the credentials associated with the "subject"
4012 * of a condition. For instance, a `rotation completed` condition applies
4013 * to a session. When that condition is met, it will produce an evaluation
4014 * against a session. Hence, in this case, the `object` credentials are the
4015 * credentials of the "subject" session.
4017 * The `trigger` credentials are the credentials of the user that registered the
4020 * The `client` credentials are the credentials of the user that created a given
4021 * notification channel.
4023 * In terms of visibility, it is expected that non-privilieged users can only
4024 * register triggers against "their" objects (their own sessions and
4025 * applications they are allowed to interact with). They can then open a
4026 * notification channel and subscribe to notifications associated with those
4029 * As for privilieged users, they can register triggers against the objects of
4030 * other users. They can then subscribe to the notifications associated to their
4031 * triggers. Privilieged users _can't_ subscribe to the notifications of
4032 * triggers owned by other users; they must create their own triggers.
4034 * This is more a concern of usability than security. It would be difficult for
4035 * a root user reliably subscribe to a specific set of conditions without
4036 * interference from external users (those could, for instance, unregister
4040 int notification_client_list_send_evaluation(
4041 struct notification_client_list
*client_list
,
4042 const struct lttng_condition
*condition
,
4043 const struct lttng_evaluation
*evaluation
,
4044 const struct lttng_credentials
*trigger_creds
,
4045 const struct lttng_credentials
*source_object_creds
,
4046 report_client_transmission_result_cb client_report
,
4050 struct lttng_payload msg_payload
;
4051 struct notification_client_list_element
*client_list_element
, *tmp
;
4052 const struct lttng_notification notification
= {
4053 .condition
= (struct lttng_condition
*) condition
,
4054 .evaluation
= (struct lttng_evaluation
*) evaluation
,
4056 struct lttng_notification_channel_message msg_header
= {
4057 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION
,
4060 lttng_payload_init(&msg_payload
);
4062 ret
= lttng_dynamic_buffer_append(&msg_payload
.buffer
, &msg_header
,
4063 sizeof(msg_header
));
4068 ret
= lttng_notification_serialize(¬ification
, &msg_payload
);
4070 ERR("[notification-thread] Failed to serialize notification");
4075 /* Update payload size. */
4076 ((struct lttng_notification_channel_message
*) msg_payload
.buffer
.data
)
4077 ->size
= (uint32_t)(
4078 msg_payload
.buffer
.size
- sizeof(msg_header
));
4080 /* Update the payload number of fds. */
4082 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
4083 &msg_payload
, 0, -1);
4085 ((struct lttng_notification_channel_message
*)
4086 msg_payload
.buffer
.data
)->fds
= (uint32_t)
4087 lttng_payload_view_get_fd_handle_count(&pv
);
4090 pthread_mutex_lock(&client_list
->lock
);
4091 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4092 &client_list
->list
, node
) {
4093 enum client_transmission_status transmission_status
;
4094 struct notification_client
*client
=
4095 client_list_element
->client
;
4098 pthread_mutex_lock(&client
->lock
);
4099 if (!client
->communication
.active
) {
4101 * Skip inactive client (protocol error or
4104 DBG("Skipping client at it is marked as inactive");
4108 if (source_object_creds
) {
4109 if (client
->uid
!= lttng_credentials_get_uid(source_object_creds
) &&
4110 client
->gid
!= lttng_credentials_get_gid(source_object_creds
) &&
4113 * Client is not allowed to monitor this
4116 DBG("[notification-thread] Skipping client at it does not have the object permission to receive notification for this trigger");
4121 if (client
->uid
!= lttng_credentials_get_uid(trigger_creds
) && client
->gid
!= lttng_credentials_get_gid(trigger_creds
)) {
4122 DBG("[notification-thread] Skipping client at it does not have the permission to receive notification for this trigger");
4126 DBG("[notification-thread] Sending notification to client (fd = %i, %zu bytes)",
4127 client
->socket
, msg_payload
.buffer
.size
);
4129 if (client_has_outbound_data_left(client
)) {
4131 * Outgoing data is already buffered for this client;
4132 * drop the notification and enqueue a "dropped
4133 * notification" message if this is the first dropped
4134 * notification since the socket spilled-over to the
4137 ret
= client_notification_overflow(client
);
4144 ret
= lttng_payload_copy(&msg_payload
, &client
->communication
.outbound
.payload
);
4150 transmission_status
= client_flush_outgoing_queue(client
);
4151 pthread_mutex_unlock(&client
->lock
);
4152 ret
= client_report(client
, transmission_status
, user_data
);
4155 goto end_unlock_list
;
4161 pthread_mutex_unlock(&client
->lock
);
4164 goto end_unlock_list
;
4170 pthread_mutex_unlock(&client_list
->lock
);
4172 lttng_payload_reset(&msg_payload
);
4176 int handle_notification_thread_event_notification(struct notification_thread_state
*state
,
4177 int notification_pipe_read_fd
,
4178 enum lttng_domain_type domain
)
4181 struct lttng_ust_event_notifier_notification ust_notification
;
4182 struct lttng_kernel_event_notifier_notification kernel_notification
;
4183 struct cds_lfht_node
*node
;
4184 struct cds_lfht_iter iter
;
4185 struct notification_trigger_tokens_ht_element
*element
;
4186 enum lttng_action_type action_type
;
4187 const struct lttng_action
*action
;
4188 struct lttng_event_notifier_notification notification
;
4189 void *reception_buffer
;
4190 size_t reception_size
;
4192 notification
.type
= domain
;
4195 case LTTNG_DOMAIN_UST
:
4196 reception_buffer
= (void *) &ust_notification
;
4197 reception_size
= sizeof(ust_notification
);
4198 notification
.notification
.ust
= &ust_notification
;
4200 case LTTNG_DOMAIN_KERNEL
:
4201 reception_buffer
= (void *) &kernel_notification
;
4202 reception_size
= sizeof(kernel_notification
);
4203 notification
.notification
.kernel
= &kernel_notification
;
4210 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4211 * ensuring that read/write of tracer notifications are atomic.
4213 ret
= lttng_read(notification_pipe_read_fd
, reception_buffer
,
4215 if (ret
!= reception_size
) {
4216 PERROR("Failed to read from event source notification pipe: fd = %d, size to read = %zu, ret = %d",
4217 notification_pipe_read_fd
, reception_size
, ret
);
4223 case LTTNG_DOMAIN_UST
:
4224 notification
.token
= ust_notification
.token
;
4226 case LTTNG_DOMAIN_KERNEL
:
4227 notification
.token
= kernel_notification
.token
;
4233 /* Find triggers associated with this token. */
4235 cds_lfht_lookup(state
->trigger_tokens_ht
,
4236 hash_key_u64(¬ification
.token
, lttng_ht_seed
),
4237 match_trigger_token
, ¬ification
.token
, &iter
);
4238 node
= cds_lfht_iter_get_node(&iter
);
4239 if (caa_likely(!node
)) {
4241 * This is not an error, slow consumption of the pipe can lead
4242 * to situations where a trigger is removed but we still get
4243 * tracer notification matching to a previous trigger.
4249 element
= caa_container_of(node
,
4250 struct notification_trigger_tokens_ht_element
,
4253 action
= lttng_trigger_get_const_action(element
->trigger
);
4254 action_type
= lttng_action_get_type(action
);
4255 DBG("Received message from tracer event source: event source fd = %d, token = %" PRIu64
", action type = '%s'",
4256 notification_pipe_read_fd
, notification
.token
,
4257 lttng_action_type_string(action_type
));
4259 /* TODO: Perform actions */
4269 int handle_notification_thread_channel_sample(
4270 struct notification_thread_state
*state
, int pipe
,
4271 enum lttng_domain_type domain
)
4274 struct lttcomm_consumer_channel_monitor_msg sample_msg
;
4275 struct channel_info
*channel_info
;
4276 struct cds_lfht_node
*node
;
4277 struct cds_lfht_iter iter
;
4278 struct lttng_channel_trigger_list
*trigger_list
;
4279 struct lttng_trigger_list_element
*trigger_list_element
;
4280 bool previous_sample_available
= false;
4281 struct channel_state_sample previous_sample
, latest_sample
;
4282 uint64_t previous_session_consumed_total
, latest_session_consumed_total
;
4283 struct lttng_credentials channel_creds
;
4286 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4287 * ensuring that read/write of sampling messages are atomic.
4289 ret
= lttng_read(pipe
, &sample_msg
, sizeof(sample_msg
));
4290 if (ret
!= sizeof(sample_msg
)) {
4291 ERR("[notification-thread] Failed to read from monitoring pipe (fd = %i)",
4298 latest_sample
.key
.key
= sample_msg
.key
;
4299 latest_sample
.key
.domain
= domain
;
4300 latest_sample
.highest_usage
= sample_msg
.highest
;
4301 latest_sample
.lowest_usage
= sample_msg
.lowest
;
4302 latest_sample
.channel_total_consumed
= sample_msg
.total_consumed
;
4306 /* Retrieve the channel's informations */
4307 cds_lfht_lookup(state
->channels_ht
,
4308 hash_channel_key(&latest_sample
.key
),
4312 node
= cds_lfht_iter_get_node(&iter
);
4313 if (caa_unlikely(!node
)) {
4315 * Not an error since the consumer can push a sample to the pipe
4316 * and the rest of the session daemon could notify us of the
4317 * channel's destruction before we get a chance to process that
4320 DBG("[notification-thread] Received a sample for an unknown channel from consumerd, key = %" PRIu64
" in %s domain",
4321 latest_sample
.key
.key
,
4322 domain
== LTTNG_DOMAIN_KERNEL
? "kernel" :
4326 channel_info
= caa_container_of(node
, struct channel_info
,
4328 DBG("[notification-thread] Handling channel sample for channel %s (key = %" PRIu64
") in session %s (highest usage = %" PRIu64
", lowest usage = %" PRIu64
", total consumed = %" PRIu64
")",
4330 latest_sample
.key
.key
,
4331 channel_info
->session_info
->name
,
4332 latest_sample
.highest_usage
,
4333 latest_sample
.lowest_usage
,
4334 latest_sample
.channel_total_consumed
);
4336 previous_session_consumed_total
=
4337 channel_info
->session_info
->consumed_data_size
;
4339 /* Retrieve the channel's last sample, if it exists, and update it. */
4340 cds_lfht_lookup(state
->channel_state_ht
,
4341 hash_channel_key(&latest_sample
.key
),
4342 match_channel_state_sample
,
4345 node
= cds_lfht_iter_get_node(&iter
);
4346 if (caa_likely(node
)) {
4347 struct channel_state_sample
*stored_sample
;
4349 /* Update the sample stored. */
4350 stored_sample
= caa_container_of(node
,
4351 struct channel_state_sample
,
4352 channel_state_ht_node
);
4354 memcpy(&previous_sample
, stored_sample
,
4355 sizeof(previous_sample
));
4356 stored_sample
->highest_usage
= latest_sample
.highest_usage
;
4357 stored_sample
->lowest_usage
= latest_sample
.lowest_usage
;
4358 stored_sample
->channel_total_consumed
= latest_sample
.channel_total_consumed
;
4359 previous_sample_available
= true;
4361 latest_session_consumed_total
=
4362 previous_session_consumed_total
+
4363 (latest_sample
.channel_total_consumed
- previous_sample
.channel_total_consumed
);
4366 * This is the channel's first sample, allocate space for and
4367 * store the new sample.
4369 struct channel_state_sample
*stored_sample
;
4371 stored_sample
= zmalloc(sizeof(*stored_sample
));
4372 if (!stored_sample
) {
4377 memcpy(stored_sample
, &latest_sample
, sizeof(*stored_sample
));
4378 cds_lfht_node_init(&stored_sample
->channel_state_ht_node
);
4379 cds_lfht_add(state
->channel_state_ht
,
4380 hash_channel_key(&stored_sample
->key
),
4381 &stored_sample
->channel_state_ht_node
);
4383 latest_session_consumed_total
=
4384 previous_session_consumed_total
+
4385 latest_sample
.channel_total_consumed
;
4388 channel_info
->session_info
->consumed_data_size
=
4389 latest_session_consumed_total
;
4391 /* Find triggers associated with this channel. */
4392 cds_lfht_lookup(state
->channel_triggers_ht
,
4393 hash_channel_key(&latest_sample
.key
),
4394 match_channel_trigger_list
,
4397 node
= cds_lfht_iter_get_node(&iter
);
4398 if (caa_likely(!node
)) {
4402 channel_creds
= (typeof(channel_creds
)) {
4403 .uid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->uid
),
4404 .gid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->gid
),
4407 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
4408 channel_triggers_ht_node
);
4409 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
4411 const struct lttng_condition
*condition
;
4412 struct lttng_trigger
*trigger
;
4413 struct notification_client_list
*client_list
= NULL
;
4414 struct lttng_evaluation
*evaluation
= NULL
;
4415 enum action_executor_status executor_status
;
4418 trigger
= trigger_list_element
->trigger
;
4419 condition
= lttng_trigger_get_const_condition(trigger
);
4423 * Check if any client is subscribed to the result of this
4426 client_list
= get_client_list_from_condition(state
, condition
);
4428 ret
= evaluate_buffer_condition(condition
, &evaluation
, state
,
4429 previous_sample_available
? &previous_sample
: NULL
,
4431 previous_session_consumed_total
,
4432 latest_session_consumed_total
,
4434 if (caa_unlikely(ret
)) {
4438 if (caa_likely(!evaluation
)) {
4442 if (!lttng_trigger_should_fire(trigger
)) {
4446 lttng_trigger_fire(trigger
);
4449 * Ownership of `evaluation` transferred to the action executor
4450 * no matter the result.
4452 executor_status
= action_executor_enqueue(state
->executor
,
4453 trigger
, evaluation
, &channel_creds
,
4456 switch (executor_status
) {
4457 case ACTION_EXECUTOR_STATUS_OK
:
4459 case ACTION_EXECUTOR_STATUS_ERROR
:
4460 case ACTION_EXECUTOR_STATUS_INVALID
:
4462 * TODO Add trigger identification (name/id) when
4463 * it is added to the API.
4465 ERR("Fatal error occurred while enqueuing action associated with buffer-condition trigger");
4468 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4470 * TODO Add trigger identification (name/id) when
4471 * it is added to the API.
4473 * Not a fatal error.
4475 WARN("No space left when enqueuing action associated with buffer-condition trigger");
4483 notification_client_list_put(client_list
);
4484 if (caa_unlikely(ret
)) {