2 * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 * SPDX-License-Identifier: GPL-2.0-only
8 #include "lttng/action/action.h"
9 #include "lttng/trigger/trigger-internal.h"
12 #include <urcu/rculfhash.h>
14 #include <common/defaults.h>
15 #include <common/error.h>
16 #include <common/futex.h>
17 #include <common/unix.h>
18 #include <common/dynamic-buffer.h>
19 #include <common/hashtable/utils.h>
20 #include <common/sessiond-comm/sessiond-comm.h>
21 #include <common/macros.h>
22 #include <lttng/condition/condition.h>
23 #include <lttng/action/action-internal.h>
24 #include <lttng/action/group-internal.h>
25 #include <lttng/domain-internal.h>
26 #include <lttng/notification/notification-internal.h>
27 #include <lttng/condition/condition-internal.h>
28 #include <lttng/condition/buffer-usage-internal.h>
29 #include <lttng/condition/session-consumed-size-internal.h>
30 #include <lttng/condition/session-rotation-internal.h>
31 #include <lttng/condition/on-event-internal.h>
32 #include <lttng/domain-internal.h>
33 #include <lttng/notification/channel-internal.h>
34 #include <lttng/trigger/trigger-internal.h>
35 #include <lttng/event-rule/event-rule-internal.h>
43 #include "condition-internal.h"
44 #include "event-notifier-error-accounting.h"
45 #include "notification-thread.h"
46 #include "notification-thread-events.h"
47 #include "notification-thread-commands.h"
48 #include "lttng-sessiond.h"
51 #define CLIENT_POLL_MASK_IN (LPOLLIN | LPOLLERR | LPOLLHUP | LPOLLRDHUP)
52 #define CLIENT_POLL_MASK_IN_OUT (CLIENT_POLL_MASK_IN | LPOLLOUT)
54 /* The tracers currently limit the capture size to PIPE_BUF (4kb on linux). */
55 #define MAX_CAPTURE_SIZE (PIPE_BUF)
57 enum lttng_object_type
{
58 LTTNG_OBJECT_TYPE_UNKNOWN
,
59 LTTNG_OBJECT_TYPE_NONE
,
60 LTTNG_OBJECT_TYPE_CHANNEL
,
61 LTTNG_OBJECT_TYPE_SESSION
,
64 struct lttng_trigger_list_element
{
65 /* No ownership of the trigger object is assumed. */
66 struct lttng_trigger
*trigger
;
67 struct cds_list_head node
;
70 struct lttng_channel_trigger_list
{
71 struct channel_key channel_key
;
72 /* List of struct lttng_trigger_list_element. */
73 struct cds_list_head list
;
74 /* Node in the channel_triggers_ht */
75 struct cds_lfht_node channel_triggers_ht_node
;
76 /* call_rcu delayed reclaim. */
77 struct rcu_head rcu_node
;
81 * List of triggers applying to a given session.
84 * - lttng_session_trigger_list_create()
85 * - lttng_session_trigger_list_build()
86 * - lttng_session_trigger_list_destroy()
87 * - lttng_session_trigger_list_add()
89 struct lttng_session_trigger_list
{
91 * Not owned by this; points to the session_info structure's
94 const char *session_name
;
95 /* List of struct lttng_trigger_list_element. */
96 struct cds_list_head list
;
97 /* Node in the session_triggers_ht */
98 struct cds_lfht_node session_triggers_ht_node
;
100 * Weak reference to the notification system's session triggers
103 * The session trigger list structure structure is owned by
104 * the session's session_info.
106 * The session_info is kept alive the the channel_infos holding a
107 * reference to it (reference counting). When those channels are
108 * destroyed (at runtime or on teardown), the reference they hold
109 * to the session_info are released. On destruction of session_info,
110 * session_info_destroy() will remove the list of triggers applying
111 * to this session from the notification system's state.
113 * This implies that the session_triggers_ht must be destroyed
114 * after the channels.
116 struct cds_lfht
*session_triggers_ht
;
117 /* Used for delayed RCU reclaim. */
118 struct rcu_head rcu_node
;
121 struct lttng_trigger_ht_element
{
122 struct lttng_trigger
*trigger
;
123 struct cds_lfht_node node
;
124 struct cds_lfht_node node_by_name_uid
;
125 struct cds_list_head client_list_trigger_node
;
126 /* call_rcu delayed reclaim. */
127 struct rcu_head rcu_node
;
130 struct lttng_condition_list_element
{
131 struct lttng_condition
*condition
;
132 struct cds_list_head node
;
135 struct channel_state_sample
{
136 struct channel_key key
;
137 struct cds_lfht_node channel_state_ht_node
;
138 uint64_t highest_usage
;
139 uint64_t lowest_usage
;
140 uint64_t channel_total_consumed
;
141 /* call_rcu delayed reclaim. */
142 struct rcu_head rcu_node
;
145 static unsigned long hash_channel_key(struct channel_key
*key
);
146 static int evaluate_buffer_condition(const struct lttng_condition
*condition
,
147 struct lttng_evaluation
**evaluation
,
148 const struct notification_thread_state
*state
,
149 const struct channel_state_sample
*previous_sample
,
150 const struct channel_state_sample
*latest_sample
,
151 uint64_t previous_session_consumed_total
,
152 uint64_t latest_session_consumed_total
,
153 struct channel_info
*channel_info
);
155 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
156 const struct lttng_evaluation
*evaluation
,
157 struct notification_client_list
*client_list
,
158 struct notification_thread_state
*state
,
159 uid_t channel_uid
, gid_t channel_gid
);
162 /* session_info API */
164 void session_info_destroy(void *_data
);
166 void session_info_get(struct session_info
*session_info
);
168 void session_info_put(struct session_info
*session_info
);
170 struct session_info
*session_info_create(const char *name
,
171 uid_t uid
, gid_t gid
,
172 struct lttng_session_trigger_list
*trigger_list
,
173 struct cds_lfht
*sessions_ht
);
175 void session_info_add_channel(struct session_info
*session_info
,
176 struct channel_info
*channel_info
);
178 void session_info_remove_channel(struct session_info
*session_info
,
179 struct channel_info
*channel_info
);
181 /* lttng_session_trigger_list API */
183 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
184 const char *session_name
,
185 struct cds_lfht
*session_triggers_ht
);
187 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
188 const struct notification_thread_state
*state
,
189 const char *session_name
);
191 void lttng_session_trigger_list_destroy(
192 struct lttng_session_trigger_list
*list
);
194 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
195 struct lttng_trigger
*trigger
);
198 int client_handle_transmission_status(
199 struct notification_client
*client
,
200 enum client_transmission_status transmission_status
,
201 struct notification_thread_state
*state
);
204 int handle_one_event_notifier_notification(
205 struct notification_thread_state
*state
,
206 int pipe
, enum lttng_domain_type domain
);
209 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
);
212 int match_client_socket(struct cds_lfht_node
*node
, const void *key
)
214 /* This double-cast is intended to supress pointer-to-cast warning. */
215 const int socket
= (int) (intptr_t) key
;
216 const struct notification_client
*client
= caa_container_of(node
,
217 struct notification_client
, client_socket_ht_node
);
219 return client
->socket
== socket
;
223 int match_client_id(struct cds_lfht_node
*node
, const void *key
)
225 /* This double-cast is intended to supress pointer-to-cast warning. */
226 const notification_client_id id
= *((notification_client_id
*) key
);
227 const struct notification_client
*client
= caa_container_of(
228 node
, struct notification_client
, client_id_ht_node
);
230 return client
->id
== id
;
234 int match_channel_trigger_list(struct cds_lfht_node
*node
, const void *key
)
236 struct channel_key
*channel_key
= (struct channel_key
*) key
;
237 struct lttng_channel_trigger_list
*trigger_list
;
239 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
240 channel_triggers_ht_node
);
242 return !!((channel_key
->key
== trigger_list
->channel_key
.key
) &&
243 (channel_key
->domain
== trigger_list
->channel_key
.domain
));
247 int match_session_trigger_list(struct cds_lfht_node
*node
, const void *key
)
249 const char *session_name
= (const char *) key
;
250 struct lttng_session_trigger_list
*trigger_list
;
252 trigger_list
= caa_container_of(node
, struct lttng_session_trigger_list
,
253 session_triggers_ht_node
);
255 return !!(strcmp(trigger_list
->session_name
, session_name
) == 0);
259 int match_channel_state_sample(struct cds_lfht_node
*node
, const void *key
)
261 struct channel_key
*channel_key
= (struct channel_key
*) key
;
262 struct channel_state_sample
*sample
;
264 sample
= caa_container_of(node
, struct channel_state_sample
,
265 channel_state_ht_node
);
267 return !!((channel_key
->key
== sample
->key
.key
) &&
268 (channel_key
->domain
== sample
->key
.domain
));
272 int match_channel_info(struct cds_lfht_node
*node
, const void *key
)
274 struct channel_key
*channel_key
= (struct channel_key
*) key
;
275 struct channel_info
*channel_info
;
277 channel_info
= caa_container_of(node
, struct channel_info
,
280 return !!((channel_key
->key
== channel_info
->key
.key
) &&
281 (channel_key
->domain
== channel_info
->key
.domain
));
285 int match_trigger(struct cds_lfht_node
*node
, const void *key
)
287 struct lttng_trigger
*trigger_key
= (struct lttng_trigger
*) key
;
288 struct lttng_trigger_ht_element
*trigger_ht_element
;
290 trigger_ht_element
= caa_container_of(node
, struct lttng_trigger_ht_element
,
293 return !!lttng_trigger_is_equal(trigger_key
, trigger_ht_element
->trigger
);
297 int match_trigger_token(struct cds_lfht_node
*node
, const void *key
)
299 const uint64_t *_key
= key
;
300 struct notification_trigger_tokens_ht_element
*element
;
302 element
= caa_container_of(node
,
303 struct notification_trigger_tokens_ht_element
, node
);
304 return *_key
== element
->token
;
308 int match_client_list_condition(struct cds_lfht_node
*node
, const void *key
)
310 struct lttng_condition
*condition_key
= (struct lttng_condition
*) key
;
311 struct notification_client_list
*client_list
;
312 const struct lttng_condition
*condition
;
314 assert(condition_key
);
316 client_list
= caa_container_of(node
, struct notification_client_list
,
317 notification_trigger_clients_ht_node
);
318 condition
= client_list
->condition
;
320 return !!lttng_condition_is_equal(condition_key
, condition
);
324 int match_session(struct cds_lfht_node
*node
, const void *key
)
326 const char *name
= key
;
327 struct session_info
*session_info
= caa_container_of(
328 node
, struct session_info
, sessions_ht_node
);
330 return !strcmp(session_info
->name
, name
);
334 const char *notification_command_type_str(
335 enum notification_thread_command_type type
)
338 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
339 return "REGISTER_TRIGGER";
340 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
341 return "UNREGISTER_TRIGGER";
342 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
343 return "ADD_CHANNEL";
344 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
345 return "REMOVE_CHANNEL";
346 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
347 return "SESSION_ROTATION_ONGOING";
348 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
349 return "SESSION_ROTATION_COMPLETED";
350 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
351 return "ADD_TRACER_EVENT_SOURCE";
352 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
353 return "REMOVE_TRACER_EVENT_SOURCE";
354 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
355 return "LIST_TRIGGERS";
356 case NOTIFICATION_COMMAND_TYPE_QUIT
:
358 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
359 return "CLIENT_COMMUNICATION_UPDATE";
366 * Match trigger based on name and credentials only.
367 * Name duplication is NOT allowed for the same uid.
370 int match_trigger_by_name_uid(struct cds_lfht_node
*node
,
375 const char *key_name
;
376 enum lttng_trigger_status status
;
377 const struct lttng_credentials
*key_creds
;
378 const struct lttng_credentials
*node_creds
;
379 const struct lttng_trigger
*trigger_key
=
380 (const struct lttng_trigger
*) key
;
381 const struct lttng_trigger_ht_element
*trigger_ht_element
=
382 caa_container_of(node
,
383 struct lttng_trigger_ht_element
,
386 status
= lttng_trigger_get_name(trigger_ht_element
->trigger
, &name
);
387 assert(status
== LTTNG_TRIGGER_STATUS_OK
);
389 status
= lttng_trigger_get_name(trigger_key
, &key_name
);
390 assert(status
== LTTNG_TRIGGER_STATUS_OK
);
392 /* Compare the names. */
393 if (strcmp(name
, key_name
) != 0) {
397 /* Compare the owners' UIDs. */
398 key_creds
= lttng_trigger_get_credentials(trigger_key
);
399 node_creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
401 match
= lttng_credentials_is_equal_uid(key_creds
, node_creds
);
408 * Hash trigger based on name and credentials only.
411 unsigned long hash_trigger_by_name_uid(const struct lttng_trigger
*trigger
)
413 unsigned long hash
= 0;
414 const struct lttng_credentials
*trigger_creds
;
415 const char *trigger_name
;
416 enum lttng_trigger_status status
;
418 status
= lttng_trigger_get_name(trigger
, &trigger_name
);
419 if (status
== LTTNG_TRIGGER_STATUS_OK
) {
420 hash
= hash_key_str(trigger_name
, lttng_ht_seed
);
423 trigger_creds
= lttng_trigger_get_credentials(trigger
);
424 hash
^= hash_key_ulong((void *) (unsigned long) LTTNG_OPTIONAL_GET(trigger_creds
->uid
),
431 unsigned long hash_channel_key(struct channel_key
*key
)
433 unsigned long key_hash
= hash_key_u64(&key
->key
, lttng_ht_seed
);
434 unsigned long domain_hash
= hash_key_ulong(
435 (void *) (unsigned long) key
->domain
, lttng_ht_seed
);
437 return key_hash
^ domain_hash
;
441 unsigned long hash_client_socket(int socket
)
443 return hash_key_ulong((void *) (unsigned long) socket
, lttng_ht_seed
);
447 unsigned long hash_client_id(notification_client_id id
)
449 return hash_key_u64(&id
, lttng_ht_seed
);
453 * Get the type of object to which a given condition applies. Bindings let
454 * the notification system evaluate a trigger's condition when a given
455 * object's state is updated.
457 * For instance, a condition bound to a channel will be evaluated everytime
458 * the channel's state is changed by a channel monitoring sample.
461 enum lttng_object_type
get_condition_binding_object(
462 const struct lttng_condition
*condition
)
464 switch (lttng_condition_get_type(condition
)) {
465 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
466 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
467 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
468 return LTTNG_OBJECT_TYPE_CHANNEL
;
469 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
470 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
471 return LTTNG_OBJECT_TYPE_SESSION
;
472 case LTTNG_CONDITION_TYPE_ON_EVENT
:
473 return LTTNG_OBJECT_TYPE_NONE
;
475 return LTTNG_OBJECT_TYPE_UNKNOWN
;
480 void free_channel_info_rcu(struct rcu_head
*node
)
482 free(caa_container_of(node
, struct channel_info
, rcu_node
));
486 void channel_info_destroy(struct channel_info
*channel_info
)
492 if (channel_info
->session_info
) {
493 session_info_remove_channel(channel_info
->session_info
,
495 session_info_put(channel_info
->session_info
);
497 if (channel_info
->name
) {
498 free(channel_info
->name
);
500 call_rcu(&channel_info
->rcu_node
, free_channel_info_rcu
);
504 void free_session_info_rcu(struct rcu_head
*node
)
506 free(caa_container_of(node
, struct session_info
, rcu_node
));
509 /* Don't call directly, use the ref-counting mechanism. */
511 void session_info_destroy(void *_data
)
513 struct session_info
*session_info
= _data
;
516 assert(session_info
);
517 if (session_info
->channel_infos_ht
) {
518 ret
= cds_lfht_destroy(session_info
->channel_infos_ht
, NULL
);
520 ERR("[notification-thread] Failed to destroy channel information hash table");
523 lttng_session_trigger_list_destroy(session_info
->trigger_list
);
526 cds_lfht_del(session_info
->sessions_ht
,
527 &session_info
->sessions_ht_node
);
529 free(session_info
->name
);
530 call_rcu(&session_info
->rcu_node
, free_session_info_rcu
);
534 void session_info_get(struct session_info
*session_info
)
539 lttng_ref_get(&session_info
->ref
);
543 void session_info_put(struct session_info
*session_info
)
548 lttng_ref_put(&session_info
->ref
);
552 struct session_info
*session_info_create(const char *name
, uid_t uid
, gid_t gid
,
553 struct lttng_session_trigger_list
*trigger_list
,
554 struct cds_lfht
*sessions_ht
)
556 struct session_info
*session_info
;
560 session_info
= zmalloc(sizeof(*session_info
));
564 lttng_ref_init(&session_info
->ref
, session_info_destroy
);
566 session_info
->channel_infos_ht
= cds_lfht_new(DEFAULT_HT_SIZE
,
567 1, 0, CDS_LFHT_AUTO_RESIZE
| CDS_LFHT_ACCOUNTING
, NULL
);
568 if (!session_info
->channel_infos_ht
) {
572 cds_lfht_node_init(&session_info
->sessions_ht_node
);
573 session_info
->name
= strdup(name
);
574 if (!session_info
->name
) {
577 session_info
->uid
= uid
;
578 session_info
->gid
= gid
;
579 session_info
->trigger_list
= trigger_list
;
580 session_info
->sessions_ht
= sessions_ht
;
584 session_info_put(session_info
);
589 void session_info_add_channel(struct session_info
*session_info
,
590 struct channel_info
*channel_info
)
593 cds_lfht_add(session_info
->channel_infos_ht
,
594 hash_channel_key(&channel_info
->key
),
595 &channel_info
->session_info_channels_ht_node
);
600 void session_info_remove_channel(struct session_info
*session_info
,
601 struct channel_info
*channel_info
)
604 cds_lfht_del(session_info
->channel_infos_ht
,
605 &channel_info
->session_info_channels_ht_node
);
610 struct channel_info
*channel_info_create(const char *channel_name
,
611 struct channel_key
*channel_key
, uint64_t channel_capacity
,
612 struct session_info
*session_info
)
614 struct channel_info
*channel_info
= zmalloc(sizeof(*channel_info
));
620 cds_lfht_node_init(&channel_info
->channels_ht_node
);
621 cds_lfht_node_init(&channel_info
->session_info_channels_ht_node
);
622 memcpy(&channel_info
->key
, channel_key
, sizeof(*channel_key
));
623 channel_info
->capacity
= channel_capacity
;
625 channel_info
->name
= strdup(channel_name
);
626 if (!channel_info
->name
) {
631 * Set the references between session and channel infos:
632 * - channel_info holds a strong reference to session_info
633 * - session_info holds a weak reference to channel_info
635 session_info_get(session_info
);
636 session_info_add_channel(session_info
, channel_info
);
637 channel_info
->session_info
= session_info
;
641 channel_info_destroy(channel_info
);
646 bool notification_client_list_get(struct notification_client_list
*list
)
648 return urcu_ref_get_unless_zero(&list
->ref
);
652 void free_notification_client_list_rcu(struct rcu_head
*node
)
654 free(caa_container_of(node
, struct notification_client_list
,
659 void notification_client_list_release(struct urcu_ref
*list_ref
)
661 struct notification_client_list
*list
=
662 container_of(list_ref
, typeof(*list
), ref
);
663 struct notification_client_list_element
*client_list_element
, *tmp
;
665 lttng_condition_put(list
->condition
);
667 if (list
->notification_trigger_clients_ht
) {
670 cds_lfht_del(list
->notification_trigger_clients_ht
,
671 &list
->notification_trigger_clients_ht_node
);
673 list
->notification_trigger_clients_ht
= NULL
;
675 cds_list_for_each_entry_safe(client_list_element
, tmp
,
676 &list
->clients_list
, node
) {
677 free(client_list_element
);
680 assert(cds_list_empty(&list
->triggers_list
));
682 pthread_mutex_destroy(&list
->lock
);
683 call_rcu(&list
->rcu_node
, free_notification_client_list_rcu
);
687 bool condition_applies_to_client(const struct lttng_condition
*condition
,
688 struct notification_client
*client
)
690 bool applies
= false;
691 struct lttng_condition_list_element
*condition_list_element
;
693 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
,
695 applies
= lttng_condition_is_equal(
696 condition_list_element
->condition
,
707 struct notification_client_list
*notification_client_list_create(
708 struct notification_thread_state
*state
,
709 const struct lttng_condition
*condition
)
711 struct notification_client
*client
;
712 struct cds_lfht_iter iter
;
713 struct notification_client_list
*client_list
;
715 client_list
= zmalloc(sizeof(*client_list
));
717 PERROR("Failed to allocate notification client list");
721 pthread_mutex_init(&client_list
->lock
, NULL
);
723 * The trigger that owns the condition has the first reference to this
726 urcu_ref_init(&client_list
->ref
);
727 cds_lfht_node_init(&client_list
->notification_trigger_clients_ht_node
);
728 CDS_INIT_LIST_HEAD(&client_list
->clients_list
);
729 CDS_INIT_LIST_HEAD(&client_list
->triggers_list
);
732 * Create a copy of the condition so that it's independent of any
733 * trigger. The client list may outlive the trigger object (which owns
734 * the condition) that is used to create it.
736 client_list
->condition
= lttng_condition_copy(condition
);
738 /* Build a list of clients to which this new condition applies. */
739 cds_lfht_for_each_entry (state
->client_socket_ht
, &iter
, client
,
740 client_socket_ht_node
) {
741 struct notification_client_list_element
*client_list_element
;
743 if (!condition_applies_to_client(condition
, client
)) {
747 client_list_element
= zmalloc(sizeof(*client_list_element
));
748 if (!client_list_element
) {
749 goto error_put_client_list
;
752 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
753 client_list_element
->client
= client
;
754 cds_list_add(&client_list_element
->node
, &client_list
->clients_list
);
757 client_list
->notification_trigger_clients_ht
=
758 state
->notification_trigger_clients_ht
;
762 * Add the client list to the global list of client list.
764 cds_lfht_add_unique(state
->notification_trigger_clients_ht
,
765 lttng_condition_hash(client_list
->condition
),
766 match_client_list_condition
,
767 client_list
->condition
,
768 &client_list
->notification_trigger_clients_ht_node
);
772 error_put_client_list
:
773 notification_client_list_put(client_list
);
780 void notification_client_list_put(struct notification_client_list
*list
)
785 return urcu_ref_put(&list
->ref
, notification_client_list_release
);
788 /* Provides a reference to the returned list. */
790 struct notification_client_list
*get_client_list_from_condition(
791 struct notification_thread_state
*state
,
792 const struct lttng_condition
*condition
)
794 struct cds_lfht_node
*node
;
795 struct cds_lfht_iter iter
;
796 struct notification_client_list
*list
= NULL
;
799 cds_lfht_lookup(state
->notification_trigger_clients_ht
,
800 lttng_condition_hash(condition
),
801 match_client_list_condition
,
804 node
= cds_lfht_iter_get_node(&iter
);
806 list
= container_of(node
, struct notification_client_list
,
807 notification_trigger_clients_ht_node
);
808 list
= notification_client_list_get(list
) ? list
: NULL
;
816 int evaluate_channel_condition_for_client(
817 const struct lttng_condition
*condition
,
818 struct notification_thread_state
*state
,
819 struct lttng_evaluation
**evaluation
,
820 uid_t
*session_uid
, gid_t
*session_gid
)
823 struct cds_lfht_iter iter
;
824 struct cds_lfht_node
*node
;
825 struct channel_info
*channel_info
= NULL
;
826 struct channel_key
*channel_key
= NULL
;
827 struct channel_state_sample
*last_sample
= NULL
;
828 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
832 /* Find the channel associated with the condition. */
833 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
,
834 channel_trigger_list
, channel_triggers_ht_node
) {
835 struct lttng_trigger_list_element
*element
;
837 cds_list_for_each_entry(element
, &channel_trigger_list
->list
, node
) {
838 const struct lttng_condition
*current_condition
=
839 lttng_trigger_get_const_condition(
842 assert(current_condition
);
843 if (!lttng_condition_is_equal(condition
,
844 current_condition
)) {
848 /* Found the trigger, save the channel key. */
849 channel_key
= &channel_trigger_list
->channel_key
;
853 /* The channel key was found stop iteration. */
859 /* No channel found; normal exit. */
860 DBG("[notification-thread] No known channel associated with newly subscribed-to condition");
865 /* Fetch channel info for the matching channel. */
866 cds_lfht_lookup(state
->channels_ht
,
867 hash_channel_key(channel_key
),
871 node
= cds_lfht_iter_get_node(&iter
);
873 channel_info
= caa_container_of(node
, struct channel_info
,
876 /* Retrieve the channel's last sample, if it exists. */
877 cds_lfht_lookup(state
->channel_state_ht
,
878 hash_channel_key(channel_key
),
879 match_channel_state_sample
,
882 node
= cds_lfht_iter_get_node(&iter
);
884 last_sample
= caa_container_of(node
,
885 struct channel_state_sample
,
886 channel_state_ht_node
);
888 /* Nothing to evaluate, no sample was ever taken. Normal exit */
889 DBG("[notification-thread] No channel sample associated with newly subscribed-to condition");
894 ret
= evaluate_buffer_condition(condition
, evaluation
, state
,
896 0, channel_info
->session_info
->consumed_data_size
,
899 WARN("[notification-thread] Fatal error occurred while evaluating a newly subscribed-to condition");
903 *session_uid
= channel_info
->session_info
->uid
;
904 *session_gid
= channel_info
->session_info
->gid
;
911 const char *get_condition_session_name(const struct lttng_condition
*condition
)
913 const char *session_name
= NULL
;
914 enum lttng_condition_status status
;
916 switch (lttng_condition_get_type(condition
)) {
917 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
918 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
919 status
= lttng_condition_buffer_usage_get_session_name(
920 condition
, &session_name
);
922 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
923 status
= lttng_condition_session_consumed_size_get_session_name(
924 condition
, &session_name
);
926 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
927 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
928 status
= lttng_condition_session_rotation_get_session_name(
929 condition
, &session_name
);
934 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
935 ERR("[notification-thread] Failed to retrieve session rotation condition's session name");
943 int evaluate_session_condition_for_client(
944 const struct lttng_condition
*condition
,
945 struct notification_thread_state
*state
,
946 struct lttng_evaluation
**evaluation
,
947 uid_t
*session_uid
, gid_t
*session_gid
)
950 struct cds_lfht_iter iter
;
951 struct cds_lfht_node
*node
;
952 const char *session_name
;
953 struct session_info
*session_info
= NULL
;
956 session_name
= get_condition_session_name(condition
);
958 /* Find the session associated with the trigger. */
959 cds_lfht_lookup(state
->sessions_ht
,
960 hash_key_str(session_name
, lttng_ht_seed
),
964 node
= cds_lfht_iter_get_node(&iter
);
966 DBG("[notification-thread] No known session matching name \"%s\"",
972 session_info
= caa_container_of(node
, struct session_info
,
974 session_info_get(session_info
);
977 * Evaluation is performed in-line here since only one type of
978 * session-bound condition is handled for the moment.
980 switch (lttng_condition_get_type(condition
)) {
981 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
982 if (!session_info
->rotation
.ongoing
) {
984 goto end_session_put
;
987 *evaluation
= lttng_evaluation_session_rotation_ongoing_create(
988 session_info
->rotation
.id
);
991 ERR("[notification-thread] Failed to create session rotation ongoing evaluation for session \"%s\"",
994 goto end_session_put
;
1000 goto end_session_put
;
1003 *session_uid
= session_info
->uid
;
1004 *session_gid
= session_info
->gid
;
1007 session_info_put(session_info
);
1014 int evaluate_condition_for_client(const struct lttng_trigger
*trigger
,
1015 const struct lttng_condition
*condition
,
1016 struct notification_client
*client
,
1017 struct notification_thread_state
*state
)
1020 struct lttng_evaluation
*evaluation
= NULL
;
1021 struct notification_client_list client_list
= {
1022 .lock
= PTHREAD_MUTEX_INITIALIZER
,
1024 struct notification_client_list_element client_list_element
= { 0 };
1025 uid_t object_uid
= 0;
1026 gid_t object_gid
= 0;
1033 switch (get_condition_binding_object(condition
)) {
1034 case LTTNG_OBJECT_TYPE_SESSION
:
1035 ret
= evaluate_session_condition_for_client(condition
, state
,
1036 &evaluation
, &object_uid
, &object_gid
);
1038 case LTTNG_OBJECT_TYPE_CHANNEL
:
1039 ret
= evaluate_channel_condition_for_client(condition
, state
,
1040 &evaluation
, &object_uid
, &object_gid
);
1042 case LTTNG_OBJECT_TYPE_NONE
:
1043 DBG("[notification-thread] Newly subscribed-to condition not bound to object, nothing to evaluate");
1046 case LTTNG_OBJECT_TYPE_UNKNOWN
:
1056 /* Evaluation yielded nothing. Normal exit. */
1057 DBG("[notification-thread] Newly subscribed-to condition evaluated to false, nothing to report to client");
1063 * Create a temporary client list with the client currently
1066 cds_lfht_node_init(&client_list
.notification_trigger_clients_ht_node
);
1067 CDS_INIT_LIST_HEAD(&client_list
.clients_list
);
1069 CDS_INIT_LIST_HEAD(&client_list_element
.node
);
1070 client_list_element
.client
= client
;
1071 cds_list_add(&client_list_element
.node
, &client_list
.clients_list
);
1073 /* Send evaluation result to the newly-subscribed client. */
1074 DBG("[notification-thread] Newly subscribed-to condition evaluated to true, notifying client");
1075 ret
= send_evaluation_to_clients(trigger
, evaluation
, &client_list
,
1076 state
, object_uid
, object_gid
);
1083 int notification_thread_client_subscribe(struct notification_client
*client
,
1084 struct lttng_condition
*condition
,
1085 struct notification_thread_state
*state
,
1086 enum lttng_notification_channel_status
*_status
)
1089 struct notification_client_list
*client_list
= NULL
;
1090 struct lttng_condition_list_element
*condition_list_element
= NULL
;
1091 struct notification_client_list_element
*client_list_element
= NULL
;
1092 struct lttng_trigger_ht_element
*trigger_ht_element
;
1093 enum lttng_notification_channel_status status
=
1094 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1097 * Ensure that the client has not already subscribed to this condition
1100 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
, node
) {
1101 if (lttng_condition_is_equal(condition_list_element
->condition
,
1103 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_ALREADY_SUBSCRIBED
;
1108 condition_list_element
= zmalloc(sizeof(*condition_list_element
));
1109 if (!condition_list_element
) {
1113 client_list_element
= zmalloc(sizeof(*client_list_element
));
1114 if (!client_list_element
) {
1120 * Add the newly-subscribed condition to the client's subscription list.
1122 CDS_INIT_LIST_HEAD(&condition_list_element
->node
);
1123 condition_list_element
->condition
= condition
;
1124 cds_list_add(&condition_list_element
->node
, &client
->condition_list
);
1126 client_list
= get_client_list_from_condition(state
, condition
);
1129 * No notification-emiting trigger registered with this
1130 * condition. We don't evaluate the condition right away
1131 * since this trigger is not registered yet.
1133 free(client_list_element
);
1138 * The condition to which the client just subscribed is evaluated
1139 * at this point so that conditions that are already TRUE result
1140 * in a notification being sent out.
1142 * Note the iteration on all triggers which share an identical
1143 * `condition` than the one to which the client is registering. This is
1144 * done to ensure that the client receives a distinct notification for
1145 * all triggers that have a `notify` action that have this condition.
1147 pthread_mutex_lock(&client_list
->lock
);
1148 cds_list_for_each_entry(trigger_ht_element
,
1149 &client_list
->triggers_list
, client_list_trigger_node
) {
1150 if (evaluate_condition_for_client(trigger_ht_element
->trigger
, condition
,
1152 WARN("[notification-thread] Evaluation of a condition on client subscription failed, aborting.");
1154 free(client_list_element
);
1155 pthread_mutex_unlock(&client_list
->lock
);
1159 pthread_mutex_unlock(&client_list
->lock
);
1162 * Add the client to the list of clients interested in a given trigger
1163 * if a "notification" trigger with a corresponding condition was
1166 client_list_element
->client
= client
;
1167 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
1169 pthread_mutex_lock(&client_list
->lock
);
1170 cds_list_add(&client_list_element
->node
, &client_list
->clients_list
);
1171 pthread_mutex_unlock(&client_list
->lock
);
1177 notification_client_list_put(client_list
);
1181 free(condition_list_element
);
1182 free(client_list_element
);
1187 int notification_thread_client_unsubscribe(
1188 struct notification_client
*client
,
1189 struct lttng_condition
*condition
,
1190 struct notification_thread_state
*state
,
1191 enum lttng_notification_channel_status
*_status
)
1193 struct notification_client_list
*client_list
;
1194 struct lttng_condition_list_element
*condition_list_element
,
1196 struct notification_client_list_element
*client_list_element
,
1198 bool condition_found
= false;
1199 enum lttng_notification_channel_status status
=
1200 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1202 /* Remove the condition from the client's condition list. */
1203 cds_list_for_each_entry_safe(condition_list_element
, condition_tmp
,
1204 &client
->condition_list
, node
) {
1205 if (!lttng_condition_is_equal(condition_list_element
->condition
,
1210 cds_list_del(&condition_list_element
->node
);
1212 * The caller may be iterating on the client's conditions to
1213 * tear down a client's connection. In this case, the condition
1214 * will be destroyed at the end.
1216 if (condition
!= condition_list_element
->condition
) {
1217 lttng_condition_destroy(
1218 condition_list_element
->condition
);
1220 free(condition_list_element
);
1221 condition_found
= true;
1225 if (!condition_found
) {
1226 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNKNOWN_CONDITION
;
1231 * Remove the client from the list of clients interested the trigger
1232 * matching the condition.
1234 client_list
= get_client_list_from_condition(state
, condition
);
1239 pthread_mutex_lock(&client_list
->lock
);
1240 cds_list_for_each_entry_safe(client_list_element
, client_tmp
,
1241 &client_list
->clients_list
, node
) {
1242 if (client_list_element
->client
->id
!= client
->id
) {
1245 cds_list_del(&client_list_element
->node
);
1246 free(client_list_element
);
1249 pthread_mutex_unlock(&client_list
->lock
);
1250 notification_client_list_put(client_list
);
1253 lttng_condition_destroy(condition
);
1261 void free_notification_client_rcu(struct rcu_head
*node
)
1263 free(caa_container_of(node
, struct notification_client
, rcu_node
));
1267 void notification_client_destroy(struct notification_client
*client
,
1268 struct notification_thread_state
*state
)
1275 * The client object is not reachable by other threads, no need to lock
1278 if (client
->socket
>= 0) {
1279 (void) lttcomm_close_unix_sock(client
->socket
);
1280 client
->socket
= -1;
1282 client
->communication
.active
= false;
1283 lttng_payload_reset(&client
->communication
.inbound
.payload
);
1284 lttng_payload_reset(&client
->communication
.outbound
.payload
);
1285 pthread_mutex_destroy(&client
->lock
);
1286 call_rcu(&client
->rcu_node
, free_notification_client_rcu
);
1290 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1294 struct notification_client
*get_client_from_socket(int socket
,
1295 struct notification_thread_state
*state
)
1297 struct cds_lfht_iter iter
;
1298 struct cds_lfht_node
*node
;
1299 struct notification_client
*client
= NULL
;
1301 cds_lfht_lookup(state
->client_socket_ht
,
1302 hash_client_socket(socket
),
1303 match_client_socket
,
1304 (void *) (unsigned long) socket
,
1306 node
= cds_lfht_iter_get_node(&iter
);
1311 client
= caa_container_of(node
, struct notification_client
,
1312 client_socket_ht_node
);
1318 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1322 struct notification_client
*get_client_from_id(notification_client_id id
,
1323 struct notification_thread_state
*state
)
1325 struct cds_lfht_iter iter
;
1326 struct cds_lfht_node
*node
;
1327 struct notification_client
*client
= NULL
;
1329 cds_lfht_lookup(state
->client_id_ht
,
1334 node
= cds_lfht_iter_get_node(&iter
);
1339 client
= caa_container_of(node
, struct notification_client
,
1346 bool buffer_usage_condition_applies_to_channel(
1347 const struct lttng_condition
*condition
,
1348 const struct channel_info
*channel_info
)
1350 enum lttng_condition_status status
;
1351 enum lttng_domain_type condition_domain
;
1352 const char *condition_session_name
= NULL
;
1353 const char *condition_channel_name
= NULL
;
1355 status
= lttng_condition_buffer_usage_get_domain_type(condition
,
1357 assert(status
== LTTNG_CONDITION_STATUS_OK
);
1358 if (channel_info
->key
.domain
!= condition_domain
) {
1362 status
= lttng_condition_buffer_usage_get_session_name(
1363 condition
, &condition_session_name
);
1364 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1366 status
= lttng_condition_buffer_usage_get_channel_name(
1367 condition
, &condition_channel_name
);
1368 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_channel_name
);
1370 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1373 if (strcmp(channel_info
->name
, condition_channel_name
)) {
1383 bool session_consumed_size_condition_applies_to_channel(
1384 const struct lttng_condition
*condition
,
1385 const struct channel_info
*channel_info
)
1387 enum lttng_condition_status status
;
1388 const char *condition_session_name
= NULL
;
1390 status
= lttng_condition_session_consumed_size_get_session_name(
1391 condition
, &condition_session_name
);
1392 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1394 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1404 bool trigger_applies_to_channel(const struct lttng_trigger
*trigger
,
1405 const struct channel_info
*channel_info
)
1407 const struct lttng_condition
*condition
;
1408 bool trigger_applies
;
1410 condition
= lttng_trigger_get_const_condition(trigger
);
1415 switch (lttng_condition_get_type(condition
)) {
1416 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
1417 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
1418 trigger_applies
= buffer_usage_condition_applies_to_channel(
1419 condition
, channel_info
);
1421 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
1422 trigger_applies
= session_consumed_size_condition_applies_to_channel(
1423 condition
, channel_info
);
1429 return trigger_applies
;
1434 /* Must be called with RCU read lock held. */
1436 struct lttng_session_trigger_list
*get_session_trigger_list(
1437 struct notification_thread_state
*state
,
1438 const char *session_name
)
1440 struct lttng_session_trigger_list
*list
= NULL
;
1441 struct cds_lfht_node
*node
;
1442 struct cds_lfht_iter iter
;
1444 cds_lfht_lookup(state
->session_triggers_ht
,
1445 hash_key_str(session_name
, lttng_ht_seed
),
1446 match_session_trigger_list
,
1449 node
= cds_lfht_iter_get_node(&iter
);
1452 * Not an error, the list of triggers applying to that session
1453 * will be initialized when the session is created.
1455 DBG("[notification-thread] No trigger list found for session \"%s\" as it is not yet known to the notification system",
1460 list
= caa_container_of(node
,
1461 struct lttng_session_trigger_list
,
1462 session_triggers_ht_node
);
1468 * Allocate an empty lttng_session_trigger_list for the session named
1471 * No ownership of 'session_name' is assumed by the session trigger list.
1472 * It is the caller's responsability to ensure the session name is alive
1473 * for as long as this list is.
1476 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
1477 const char *session_name
,
1478 struct cds_lfht
*session_triggers_ht
)
1480 struct lttng_session_trigger_list
*list
;
1482 list
= zmalloc(sizeof(*list
));
1486 list
->session_name
= session_name
;
1487 CDS_INIT_LIST_HEAD(&list
->list
);
1488 cds_lfht_node_init(&list
->session_triggers_ht_node
);
1489 list
->session_triggers_ht
= session_triggers_ht
;
1492 /* Publish the list through the session_triggers_ht. */
1493 cds_lfht_add(session_triggers_ht
,
1494 hash_key_str(session_name
, lttng_ht_seed
),
1495 &list
->session_triggers_ht_node
);
1502 void free_session_trigger_list_rcu(struct rcu_head
*node
)
1504 free(caa_container_of(node
, struct lttng_session_trigger_list
,
1509 void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list
*list
)
1511 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1513 /* Empty the list element by element, and then free the list itself. */
1514 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1515 &list
->list
, node
) {
1516 cds_list_del(&trigger_list_element
->node
);
1517 free(trigger_list_element
);
1520 /* Unpublish the list from the session_triggers_ht. */
1521 cds_lfht_del(list
->session_triggers_ht
,
1522 &list
->session_triggers_ht_node
);
1524 call_rcu(&list
->rcu_node
, free_session_trigger_list_rcu
);
1528 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
1529 struct lttng_trigger
*trigger
)
1532 struct lttng_trigger_list_element
*new_element
=
1533 zmalloc(sizeof(*new_element
));
1539 CDS_INIT_LIST_HEAD(&new_element
->node
);
1540 new_element
->trigger
= trigger
;
1541 cds_list_add(&new_element
->node
, &list
->list
);
1547 bool trigger_applies_to_session(const struct lttng_trigger
*trigger
,
1548 const char *session_name
)
1550 bool applies
= false;
1551 const struct lttng_condition
*condition
;
1553 condition
= lttng_trigger_get_const_condition(trigger
);
1554 switch (lttng_condition_get_type(condition
)) {
1555 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1556 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1558 enum lttng_condition_status condition_status
;
1559 const char *condition_session_name
;
1561 condition_status
= lttng_condition_session_rotation_get_session_name(
1562 condition
, &condition_session_name
);
1563 if (condition_status
!= LTTNG_CONDITION_STATUS_OK
) {
1564 ERR("[notification-thread] Failed to retrieve session rotation condition's session name");
1568 assert(condition_session_name
);
1569 applies
= !strcmp(condition_session_name
, session_name
);
1580 * Allocate and initialize an lttng_session_trigger_list which contains
1581 * all triggers that apply to the session named 'session_name'.
1583 * No ownership of 'session_name' is assumed by the session trigger list.
1584 * It is the caller's responsability to ensure the session name is alive
1585 * for as long as this list is.
1588 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
1589 const struct notification_thread_state
*state
,
1590 const char *session_name
)
1592 int trigger_count
= 0;
1593 struct lttng_session_trigger_list
*session_trigger_list
= NULL
;
1594 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1595 struct cds_lfht_iter iter
;
1597 session_trigger_list
= lttng_session_trigger_list_create(session_name
,
1598 state
->session_triggers_ht
);
1600 /* Add all triggers applying to the session named 'session_name'. */
1601 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1605 if (!trigger_applies_to_session(trigger_ht_element
->trigger
,
1610 ret
= lttng_session_trigger_list_add(session_trigger_list
,
1611 trigger_ht_element
->trigger
);
1619 DBG("[notification-thread] Found %i triggers that apply to newly created session",
1621 return session_trigger_list
;
1623 lttng_session_trigger_list_destroy(session_trigger_list
);
1628 struct session_info
*find_or_create_session_info(
1629 struct notification_thread_state
*state
,
1630 const char *name
, uid_t uid
, gid_t gid
)
1632 struct session_info
*session
= NULL
;
1633 struct cds_lfht_node
*node
;
1634 struct cds_lfht_iter iter
;
1635 struct lttng_session_trigger_list
*trigger_list
;
1638 cds_lfht_lookup(state
->sessions_ht
,
1639 hash_key_str(name
, lttng_ht_seed
),
1643 node
= cds_lfht_iter_get_node(&iter
);
1645 DBG("[notification-thread] Found session info of session \"%s\" (uid = %i, gid = %i)",
1647 session
= caa_container_of(node
, struct session_info
,
1649 assert(session
->uid
== uid
);
1650 assert(session
->gid
== gid
);
1651 session_info_get(session
);
1655 trigger_list
= lttng_session_trigger_list_build(state
, name
);
1656 if (!trigger_list
) {
1660 session
= session_info_create(name
, uid
, gid
, trigger_list
,
1661 state
->sessions_ht
);
1663 ERR("[notification-thread] Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
1665 lttng_session_trigger_list_destroy(trigger_list
);
1668 trigger_list
= NULL
;
1670 cds_lfht_add(state
->sessions_ht
, hash_key_str(name
, lttng_ht_seed
),
1671 &session
->sessions_ht_node
);
1677 session_info_put(session
);
1682 int handle_notification_thread_command_add_channel(
1683 struct notification_thread_state
*state
,
1684 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1685 const char *channel_name
, enum lttng_domain_type channel_domain
,
1686 uint64_t channel_key_int
, uint64_t channel_capacity
,
1687 enum lttng_error_code
*cmd_result
)
1689 struct cds_list_head trigger_list
;
1690 struct channel_info
*new_channel_info
= NULL
;
1691 struct channel_key channel_key
= {
1692 .key
= channel_key_int
,
1693 .domain
= channel_domain
,
1695 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
1696 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1697 int trigger_count
= 0;
1698 struct cds_lfht_iter iter
;
1699 struct session_info
*session_info
= NULL
;
1701 DBG("[notification-thread] Adding channel %s from session %s, channel key = %" PRIu64
" in %s domain",
1702 channel_name
, session_name
, channel_key_int
,
1703 lttng_domain_type_str(channel_domain
));
1705 CDS_INIT_LIST_HEAD(&trigger_list
);
1707 session_info
= find_or_create_session_info(state
, session_name
,
1708 session_uid
, session_gid
);
1709 if (!session_info
) {
1710 /* Allocation error or an internal error occurred. */
1714 new_channel_info
= channel_info_create(channel_name
, &channel_key
,
1715 channel_capacity
, session_info
);
1716 if (!new_channel_info
) {
1721 /* Build a list of all triggers applying to the new channel. */
1722 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1724 struct lttng_trigger_list_element
*new_element
;
1726 if (!trigger_applies_to_channel(trigger_ht_element
->trigger
,
1727 new_channel_info
)) {
1731 new_element
= zmalloc(sizeof(*new_element
));
1736 CDS_INIT_LIST_HEAD(&new_element
->node
);
1737 new_element
->trigger
= trigger_ht_element
->trigger
;
1738 cds_list_add(&new_element
->node
, &trigger_list
);
1743 DBG("[notification-thread] Found %i triggers that apply to newly added channel",
1745 channel_trigger_list
= zmalloc(sizeof(*channel_trigger_list
));
1746 if (!channel_trigger_list
) {
1749 channel_trigger_list
->channel_key
= new_channel_info
->key
;
1750 CDS_INIT_LIST_HEAD(&channel_trigger_list
->list
);
1751 cds_lfht_node_init(&channel_trigger_list
->channel_triggers_ht_node
);
1752 cds_list_splice(&trigger_list
, &channel_trigger_list
->list
);
1755 /* Add channel to the channel_ht which owns the channel_infos. */
1756 cds_lfht_add(state
->channels_ht
,
1757 hash_channel_key(&new_channel_info
->key
),
1758 &new_channel_info
->channels_ht_node
);
1760 * Add the list of triggers associated with this channel to the
1761 * channel_triggers_ht.
1763 cds_lfht_add(state
->channel_triggers_ht
,
1764 hash_channel_key(&new_channel_info
->key
),
1765 &channel_trigger_list
->channel_triggers_ht_node
);
1767 session_info_put(session_info
);
1768 *cmd_result
= LTTNG_OK
;
1771 channel_info_destroy(new_channel_info
);
1772 session_info_put(session_info
);
1777 void free_channel_trigger_list_rcu(struct rcu_head
*node
)
1779 free(caa_container_of(node
, struct lttng_channel_trigger_list
,
1784 void free_channel_state_sample_rcu(struct rcu_head
*node
)
1786 free(caa_container_of(node
, struct channel_state_sample
,
1791 int handle_notification_thread_command_remove_channel(
1792 struct notification_thread_state
*state
,
1793 uint64_t channel_key
, enum lttng_domain_type domain
,
1794 enum lttng_error_code
*cmd_result
)
1796 struct cds_lfht_node
*node
;
1797 struct cds_lfht_iter iter
;
1798 struct lttng_channel_trigger_list
*trigger_list
;
1799 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1800 struct channel_key key
= { .key
= channel_key
, .domain
= domain
};
1801 struct channel_info
*channel_info
;
1803 DBG("[notification-thread] Removing channel key = %" PRIu64
" in %s domain",
1804 channel_key
, lttng_domain_type_str(domain
));
1808 cds_lfht_lookup(state
->channel_triggers_ht
,
1809 hash_channel_key(&key
),
1810 match_channel_trigger_list
,
1813 node
= cds_lfht_iter_get_node(&iter
);
1815 * There is a severe internal error if we are being asked to remove a
1816 * channel that doesn't exist.
1819 ERR("[notification-thread] Channel being removed is unknown to the notification thread");
1823 /* Free the list of triggers associated with this channel. */
1824 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
1825 channel_triggers_ht_node
);
1826 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1827 &trigger_list
->list
, node
) {
1828 cds_list_del(&trigger_list_element
->node
);
1829 free(trigger_list_element
);
1831 cds_lfht_del(state
->channel_triggers_ht
, node
);
1832 call_rcu(&trigger_list
->rcu_node
, free_channel_trigger_list_rcu
);
1834 /* Free sampled channel state. */
1835 cds_lfht_lookup(state
->channel_state_ht
,
1836 hash_channel_key(&key
),
1837 match_channel_state_sample
,
1840 node
= cds_lfht_iter_get_node(&iter
);
1842 * This is expected to be NULL if the channel is destroyed before we
1843 * received a sample.
1846 struct channel_state_sample
*sample
= caa_container_of(node
,
1847 struct channel_state_sample
,
1848 channel_state_ht_node
);
1850 cds_lfht_del(state
->channel_state_ht
, node
);
1851 call_rcu(&sample
->rcu_node
, free_channel_state_sample_rcu
);
1854 /* Remove the channel from the channels_ht and free it. */
1855 cds_lfht_lookup(state
->channels_ht
,
1856 hash_channel_key(&key
),
1860 node
= cds_lfht_iter_get_node(&iter
);
1862 channel_info
= caa_container_of(node
, struct channel_info
,
1864 cds_lfht_del(state
->channels_ht
, node
);
1865 channel_info_destroy(channel_info
);
1868 *cmd_result
= LTTNG_OK
;
1873 int handle_notification_thread_command_session_rotation(
1874 struct notification_thread_state
*state
,
1875 enum notification_thread_command_type cmd_type
,
1876 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1877 uint64_t trace_archive_chunk_id
,
1878 struct lttng_trace_archive_location
*location
,
1879 enum lttng_error_code
*_cmd_result
)
1882 enum lttng_error_code cmd_result
= LTTNG_OK
;
1883 struct lttng_session_trigger_list
*trigger_list
;
1884 struct lttng_trigger_list_element
*trigger_list_element
;
1885 struct session_info
*session_info
;
1886 const struct lttng_credentials session_creds
= {
1887 .uid
= LTTNG_OPTIONAL_INIT_VALUE(session_uid
),
1888 .gid
= LTTNG_OPTIONAL_INIT_VALUE(session_gid
),
1893 session_info
= find_or_create_session_info(state
, session_name
,
1894 session_uid
, session_gid
);
1895 if (!session_info
) {
1896 /* Allocation error or an internal error occurred. */
1898 cmd_result
= LTTNG_ERR_NOMEM
;
1902 session_info
->rotation
.ongoing
=
1903 cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
;
1904 session_info
->rotation
.id
= trace_archive_chunk_id
;
1905 trigger_list
= get_session_trigger_list(state
, session_name
);
1906 if (!trigger_list
) {
1907 DBG("[notification-thread] No triggers applying to session \"%s\" found",
1912 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
1914 const struct lttng_condition
*condition
;
1915 struct lttng_trigger
*trigger
;
1916 struct notification_client_list
*client_list
;
1917 struct lttng_evaluation
*evaluation
= NULL
;
1918 enum lttng_condition_type condition_type
;
1919 enum action_executor_status executor_status
;
1921 trigger
= trigger_list_element
->trigger
;
1922 condition
= lttng_trigger_get_const_condition(trigger
);
1924 condition_type
= lttng_condition_get_type(condition
);
1926 if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
&&
1927 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1929 } else if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
&&
1930 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
) {
1934 client_list
= get_client_list_from_condition(state
, condition
);
1935 if (cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1936 evaluation
= lttng_evaluation_session_rotation_ongoing_create(
1937 trace_archive_chunk_id
);
1939 evaluation
= lttng_evaluation_session_rotation_completed_create(
1940 trace_archive_chunk_id
, location
);
1944 /* Internal error */
1946 cmd_result
= LTTNG_ERR_UNK
;
1951 * Ownership of `evaluation` transferred to the action executor
1952 * no matter the result.
1954 executor_status
= action_executor_enqueue(state
->executor
,
1955 trigger
, evaluation
, &session_creds
,
1958 switch (executor_status
) {
1959 case ACTION_EXECUTOR_STATUS_OK
:
1961 case ACTION_EXECUTOR_STATUS_ERROR
:
1962 case ACTION_EXECUTOR_STATUS_INVALID
:
1964 * TODO Add trigger identification (name/id) when
1965 * it is added to the API.
1967 ERR("Fatal error occurred while enqueuing action associated with session rotation trigger");
1970 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
1972 * TODO Add trigger identification (name/id) when
1973 * it is added to the API.
1975 * Not a fatal error.
1977 WARN("No space left when enqueuing action associated with session rotation trigger");
1985 notification_client_list_put(client_list
);
1986 if (caa_unlikely(ret
)) {
1991 session_info_put(session_info
);
1992 *_cmd_result
= cmd_result
;
1998 int handle_notification_thread_command_add_tracer_event_source(
1999 struct notification_thread_state
*state
,
2000 int tracer_event_source_fd
,
2001 enum lttng_domain_type domain_type
,
2002 enum lttng_error_code
*_cmd_result
)
2005 enum lttng_error_code cmd_result
= LTTNG_OK
;
2006 struct notification_event_tracer_event_source_element
*element
= NULL
;
2008 element
= zmalloc(sizeof(*element
));
2010 cmd_result
= LTTNG_ERR_NOMEM
;
2015 element
->fd
= tracer_event_source_fd
;
2016 element
->domain
= domain_type
;
2018 cds_list_add(&element
->node
, &state
->tracer_event_sources_list
);
2020 DBG3("[notification-thread] Adding tracer event source fd to poll set: tracer_event_source_fd = %d, domain = '%s'",
2021 tracer_event_source_fd
,
2022 lttng_domain_type_str(domain_type
));
2024 /* Adding the read side pipe to the event poll. */
2025 ret
= lttng_poll_add(&state
->events
, tracer_event_source_fd
, LPOLLIN
| LPOLLERR
);
2027 ERR("[notification-thread] Failed to add tracer event source to poll set: tracer_event_source_fd = %d, domain = '%s'",
2028 tracer_event_source_fd
,
2029 lttng_domain_type_str(element
->domain
));
2030 cds_list_del(&element
->node
);
2035 element
->is_fd_in_poll_set
= true;
2038 *_cmd_result
= cmd_result
;
2043 int drain_event_notifier_notification_pipe(
2044 struct notification_thread_state
*state
,
2045 int pipe
, enum lttng_domain_type domain
)
2047 struct lttng_poll_event events
= {0};
2050 ret
= lttng_poll_create(&events
, 1, LTTNG_CLOEXEC
);
2052 ERR("[notification-thread] Error creating lttng_poll_event");
2056 ret
= lttng_poll_add(&events
, pipe
, LPOLLIN
);
2058 ERR("[notification-thread] Error adding fd event notifier notification pipe to lttng_poll_event: fd = %d",
2065 * Continue to consume notifications as long as there are new
2066 * ones coming in. The tracer has been asked to stop producing
2069 * LPOLLIN is explicitly checked since LPOLLHUP is implicitly
2070 * monitored (on Linux, at least) and will be returned when
2071 * the pipe is closed but empty.
2073 ret
= lttng_poll_wait_interruptible(&events
, 0);
2074 if (ret
== 0 || (LTTNG_POLL_GETEV(&events
, 0) & LPOLLIN
) == 0) {
2075 /* No more notification to be read on this pipe. */
2078 } else if (ret
< 0) {
2079 PERROR("Failed on lttng_poll_wait_interruptible() call");
2084 ret
= handle_one_event_notifier_notification(state
, pipe
, domain
);
2086 ERR("[notification-thread] Error consuming an event notifier notification from pipe: fd = %d",
2091 lttng_poll_clean(&events
);
2096 int handle_notification_thread_command_remove_tracer_event_source(
2097 struct notification_thread_state
*state
,
2098 int tracer_event_source_fd
,
2099 enum lttng_error_code
*_cmd_result
)
2103 enum lttng_error_code cmd_result
= LTTNG_OK
;
2104 struct notification_event_tracer_event_source_element
*source_element
= NULL
, *tmp
;
2106 cds_list_for_each_entry_safe(source_element
, tmp
,
2107 &state
->tracer_event_sources_list
, node
) {
2108 if (source_element
->fd
!= tracer_event_source_fd
) {
2112 DBG("[notification-thread] Removed tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2113 tracer_event_source_fd
,
2114 lttng_domain_type_str(source_element
->domain
));
2115 cds_list_del(&source_element
->node
);
2122 * This is temporarily allowed since the poll activity set is
2123 * not properly cleaned-up for the moment. This is adressed in
2126 source_element
= NULL
;
2130 if (!source_element
->is_fd_in_poll_set
) {
2131 /* Skip the poll set removal. */
2135 DBG3("[notification-thread] Removing tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2136 tracer_event_source_fd
,
2137 lttng_domain_type_str(source_element
->domain
));
2139 /* Removing the fd from the event poll set. */
2140 ret
= lttng_poll_del(&state
->events
, tracer_event_source_fd
);
2142 ERR("[notification-thread] Failed to remove tracer event source from poll set: tracer_event_source_fd = %d, domain = '%s'",
2143 tracer_event_source_fd
,
2144 lttng_domain_type_str(source_element
->domain
));
2145 cmd_result
= LTTNG_ERR_FATAL
;
2149 source_element
->is_fd_in_poll_set
= false;
2151 ret
= drain_event_notifier_notification_pipe(state
, tracer_event_source_fd
,
2152 source_element
->domain
);
2154 ERR("[notification-thread] Error draining event notifier notification: tracer_event_source_fd = %d, domain = %s",
2155 tracer_event_source_fd
,
2156 lttng_domain_type_str(source_element
->domain
));
2157 cmd_result
= LTTNG_ERR_FATAL
;
2162 * The drain_event_notifier_notification_pipe() call might have read
2163 * data from an fd that we received in event in the latest _poll_wait()
2164 * call. Make sure the thread call poll_wait() again to ensure we have
2167 state
->restart_poll
= true;
2170 free(source_element
);
2171 *_cmd_result
= cmd_result
;
2176 int condition_on_event_update_error_count(struct lttng_trigger
*trigger
)
2179 uint64_t error_count
= 0;
2180 struct lttng_condition
*condition
;
2181 enum event_notifier_error_accounting_status status
;
2183 condition
= lttng_trigger_get_condition(trigger
);
2184 assert(lttng_condition_get_type(condition
) ==
2185 LTTNG_CONDITION_TYPE_ON_EVENT
);
2187 status
= event_notifier_error_accounting_get_count(trigger
, &error_count
);
2188 if (status
!= EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK
) {
2189 uid_t trigger_owner_uid
;
2190 const char *trigger_name
;
2191 const enum lttng_trigger_status trigger_status
=
2192 lttng_trigger_get_owner_uid(
2193 trigger
, &trigger_owner_uid
);
2195 assert(trigger_status
== LTTNG_TRIGGER_STATUS_OK
);
2196 if (lttng_trigger_get_name(trigger
, &trigger_name
) != LTTNG_TRIGGER_STATUS_OK
) {
2197 trigger_name
= "(unnamed)";
2200 ERR("Failed to get event notifier error count of trigger for update: trigger owner = %d, trigger name = '%s'",
2201 trigger_owner_uid
, trigger_name
);
2205 lttng_condition_on_event_set_error_count(condition
, error_count
);
2209 int handle_notification_thread_remove_tracer_event_source_no_result(
2210 struct notification_thread_state
*state
,
2211 int tracer_event_source_fd
)
2214 enum lttng_error_code cmd_result
;
2216 ret
= handle_notification_thread_command_remove_tracer_event_source(
2217 state
, tracer_event_source_fd
, &cmd_result
);
2222 static int handle_notification_thread_command_list_triggers(
2223 struct notification_thread_handle
*handle
,
2224 struct notification_thread_state
*state
,
2226 struct lttng_triggers
**triggers
,
2227 enum lttng_error_code
*_cmd_result
)
2230 enum lttng_error_code cmd_result
= LTTNG_OK
;
2231 struct cds_lfht_iter iter
;
2232 struct lttng_trigger_ht_element
*trigger_ht_element
;
2233 struct lttng_triggers
*local_triggers
= NULL
;
2234 const struct lttng_credentials
*creds
;
2238 local_triggers
= lttng_triggers_create();
2239 if (!local_triggers
) {
2240 /* Not a fatal error. */
2241 cmd_result
= LTTNG_ERR_NOMEM
;
2245 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
,
2246 trigger_ht_element
, node
) {
2248 * Only return the triggers to which the client has access.
2249 * The root user has visibility over all triggers.
2251 creds
= lttng_trigger_get_credentials(trigger_ht_element
->trigger
);
2252 if (client_uid
!= lttng_credentials_get_uid(creds
) && client_uid
!= 0) {
2256 if (lttng_trigger_needs_tracer_notifier(trigger_ht_element
->trigger
)) {
2257 ret
= condition_on_event_update_error_count(
2258 trigger_ht_element
->trigger
);
2262 ret
= lttng_triggers_add(local_triggers
,
2263 trigger_ht_element
->trigger
);
2265 /* Not a fatal error. */
2267 cmd_result
= LTTNG_ERR_NOMEM
;
2272 /* Transferring ownership to the caller. */
2273 *triggers
= local_triggers
;
2274 local_triggers
= NULL
;
2278 lttng_triggers_destroy(local_triggers
);
2279 *_cmd_result
= cmd_result
;
2284 bool condition_is_supported(struct lttng_condition
*condition
)
2288 switch (lttng_condition_get_type(condition
)) {
2289 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
2290 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
2293 enum lttng_domain_type domain
;
2295 ret
= lttng_condition_buffer_usage_get_domain_type(condition
,
2299 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2300 is_supported
= true;
2305 * Older kernel tracers don't expose the API to monitor their
2306 * buffers. Therefore, we reject triggers that require that
2307 * mechanism to be available to be evaluated.
2309 * Assume unsupported on error.
2311 is_supported
= kernel_supports_ring_buffer_snapshot_sample_positions() == 1;
2314 case LTTNG_CONDITION_TYPE_ON_EVENT
:
2316 const struct lttng_event_rule
*event_rule
;
2317 enum lttng_domain_type domain
;
2318 const enum lttng_condition_status status
=
2319 lttng_condition_on_event_get_rule(
2320 condition
, &event_rule
);
2322 assert(status
== LTTNG_CONDITION_STATUS_OK
);
2324 domain
= lttng_event_rule_get_domain_type(event_rule
);
2325 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
2326 is_supported
= true;
2331 * Older kernel tracers can't emit notification. Therefore, we
2332 * reject triggers that require that mechanism to be available
2335 * Assume unsupported on error.
2337 is_supported
= kernel_supports_event_notifiers() == 1;
2341 is_supported
= true;
2344 return is_supported
;
2347 /* Must be called with RCU read lock held. */
2349 int bind_trigger_to_matching_session(struct lttng_trigger
*trigger
,
2350 struct notification_thread_state
*state
)
2353 const struct lttng_condition
*condition
;
2354 const char *session_name
;
2355 struct lttng_session_trigger_list
*trigger_list
;
2357 condition
= lttng_trigger_get_const_condition(trigger
);
2358 switch (lttng_condition_get_type(condition
)) {
2359 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
2360 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
2362 enum lttng_condition_status status
;
2364 status
= lttng_condition_session_rotation_get_session_name(
2365 condition
, &session_name
);
2366 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
2367 ERR("[notification-thread] Failed to bind trigger to session: unable to get 'session_rotation' condition's session name");
2378 trigger_list
= get_session_trigger_list(state
, session_name
);
2379 if (!trigger_list
) {
2380 DBG("[notification-thread] Unable to bind trigger applying to session \"%s\" as it is not yet known to the notification system",
2386 DBG("[notification-thread] Newly registered trigger bound to session \"%s\"",
2388 ret
= lttng_session_trigger_list_add(trigger_list
, trigger
);
2393 /* Must be called with RCU read lock held. */
2395 int bind_trigger_to_matching_channels(struct lttng_trigger
*trigger
,
2396 struct notification_thread_state
*state
)
2399 struct cds_lfht_node
*node
;
2400 struct cds_lfht_iter iter
;
2401 struct channel_info
*channel
;
2403 cds_lfht_for_each_entry(state
->channels_ht
, &iter
, channel
,
2405 struct lttng_trigger_list_element
*trigger_list_element
;
2406 struct lttng_channel_trigger_list
*trigger_list
;
2407 struct cds_lfht_iter lookup_iter
;
2409 if (!trigger_applies_to_channel(trigger
, channel
)) {
2413 cds_lfht_lookup(state
->channel_triggers_ht
,
2414 hash_channel_key(&channel
->key
),
2415 match_channel_trigger_list
,
2418 node
= cds_lfht_iter_get_node(&lookup_iter
);
2420 trigger_list
= caa_container_of(node
,
2421 struct lttng_channel_trigger_list
,
2422 channel_triggers_ht_node
);
2424 trigger_list_element
= zmalloc(sizeof(*trigger_list_element
));
2425 if (!trigger_list_element
) {
2429 CDS_INIT_LIST_HEAD(&trigger_list_element
->node
);
2430 trigger_list_element
->trigger
= trigger
;
2431 cds_list_add(&trigger_list_element
->node
, &trigger_list
->list
);
2432 DBG("[notification-thread] Newly registered trigger bound to channel \"%s\"",
2440 bool is_trigger_action_notify(const struct lttng_trigger
*trigger
)
2442 bool is_notify
= false;
2443 unsigned int i
, count
;
2444 enum lttng_action_status action_status
;
2445 const struct lttng_action
*action
=
2446 lttng_trigger_get_const_action(trigger
);
2447 enum lttng_action_type action_type
;
2450 action_type
= lttng_action_get_type(action
);
2451 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2454 } else if (action_type
!= LTTNG_ACTION_TYPE_GROUP
) {
2458 action_status
= lttng_action_group_get_count(action
, &count
);
2459 assert(action_status
== LTTNG_ACTION_STATUS_OK
);
2461 for (i
= 0; i
< count
; i
++) {
2462 const struct lttng_action
*inner_action
=
2463 lttng_action_group_get_at_index(
2466 action_type
= lttng_action_get_type(inner_action
);
2467 if (action_type
== LTTNG_ACTION_TYPE_NOTIFY
) {
2477 static bool trigger_name_taken(struct notification_thread_state
*state
,
2478 const struct lttng_trigger
*trigger
)
2480 struct cds_lfht_iter iter
;
2483 * No duplicata is allowed in the triggers_by_name_uid_ht.
2484 * The match is done against the trigger name and uid.
2486 cds_lfht_lookup(state
->triggers_by_name_uid_ht
,
2487 hash_trigger_by_name_uid(trigger
),
2488 match_trigger_by_name_uid
,
2491 return !!cds_lfht_iter_get_node(&iter
);
2495 enum lttng_error_code
generate_trigger_name(
2496 struct notification_thread_state
*state
,
2497 struct lttng_trigger
*trigger
, const char **name
)
2499 enum lttng_error_code ret_code
= LTTNG_OK
;
2501 enum lttng_trigger_status status
;
2504 const int ret
= lttng_trigger_generate_name(trigger
,
2505 state
->trigger_id
.name_offset
++);
2507 /* The only reason this can fail right now. */
2508 ret_code
= LTTNG_ERR_NOMEM
;
2512 status
= lttng_trigger_get_name(trigger
, name
);
2513 assert(status
== LTTNG_TRIGGER_STATUS_OK
);
2515 taken
= trigger_name_taken(state
, trigger
);
2516 } while (taken
|| state
->trigger_id
.name_offset
== UINT64_MAX
);
2522 void notif_thread_state_remove_trigger_ht_elem(
2523 struct notification_thread_state
*state
,
2524 struct lttng_trigger_ht_element
*trigger_ht_element
)
2527 assert(trigger_ht_element
);
2529 cds_lfht_del(state
->triggers_ht
, &trigger_ht_element
->node
);
2530 cds_lfht_del(state
->triggers_by_name_uid_ht
, &trigger_ht_element
->node_by_name_uid
);
2534 enum lttng_error_code
setup_tracer_notifier(
2535 struct notification_thread_state
*state
,
2536 struct lttng_trigger
*trigger
)
2538 enum lttng_error_code ret
;
2539 enum event_notifier_error_accounting_status error_accounting_status
;
2540 struct cds_lfht_node
*node
;
2541 uint64_t error_counter_index
= 0;
2542 struct lttng_condition
*condition
= lttng_trigger_get_condition(trigger
);
2543 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
= NULL
;
2545 trigger_tokens_ht_element
= zmalloc(sizeof(*trigger_tokens_ht_element
));
2546 if (!trigger_tokens_ht_element
) {
2547 ret
= LTTNG_ERR_NOMEM
;
2551 /* Add trigger token to the trigger_tokens_ht. */
2552 cds_lfht_node_init(&trigger_tokens_ht_element
->node
);
2553 trigger_tokens_ht_element
->token
= LTTNG_OPTIONAL_GET(trigger
->tracer_token
);
2554 trigger_tokens_ht_element
->trigger
= trigger
;
2556 node
= cds_lfht_add_unique(state
->trigger_tokens_ht
,
2557 hash_key_u64(&trigger_tokens_ht_element
->token
, lttng_ht_seed
),
2558 match_trigger_token
,
2559 &trigger_tokens_ht_element
->token
,
2560 &trigger_tokens_ht_element
->node
);
2561 if (node
!= &trigger_tokens_ht_element
->node
) {
2562 ret
= LTTNG_ERR_TRIGGER_EXISTS
;
2563 goto error_free_ht_element
;
2566 error_accounting_status
= event_notifier_error_accounting_register_event_notifier(
2567 trigger
, &error_counter_index
);
2568 if (error_accounting_status
!= EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_OK
) {
2569 if (error_accounting_status
== EVENT_NOTIFIER_ERROR_ACCOUNTING_STATUS_NO_INDEX_AVAILABLE
) {
2570 DBG("Trigger group error accounting counter full.");
2571 ret
= LTTNG_ERR_EVENT_NOTIFIER_ERROR_ACCOUNTING_FULL
;
2573 ERR("Error registering trigger for error accounting");
2574 ret
= LTTNG_ERR_EVENT_NOTIFIER_REGISTRATION
;
2577 goto error_remove_ht_element
;
2580 lttng_condition_on_event_set_error_counter_index(
2581 condition
, error_counter_index
);
2586 error_remove_ht_element
:
2587 cds_lfht_del(state
->trigger_tokens_ht
, &trigger_tokens_ht_element
->node
);
2588 error_free_ht_element
:
2589 free(trigger_tokens_ht_element
);
2595 * FIXME A client's credentials are not checked when registering a trigger.
2597 * The effects of this are benign since:
2598 * - The client will succeed in registering the trigger, as it is valid,
2599 * - The trigger will, internally, be bound to the channel/session,
2600 * - The notifications will not be sent since the client's credentials
2601 * are checked against the channel at that moment.
2603 * If this function returns a non-zero value, it means something is
2604 * fundamentally broken and the whole subsystem/thread will be torn down.
2606 * If a non-fatal error occurs, just set the cmd_result to the appropriate
2610 int handle_notification_thread_command_register_trigger(
2611 struct notification_thread_state
*state
,
2612 struct lttng_trigger
*trigger
,
2613 enum lttng_error_code
*cmd_result
)
2616 struct lttng_condition
*condition
;
2617 struct notification_client_list
*client_list
= NULL
;
2618 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2619 struct cds_lfht_node
*node
;
2620 const char* trigger_name
;
2621 bool free_trigger
= true;
2622 struct lttng_evaluation
*evaluation
= NULL
;
2623 struct lttng_credentials object_creds
;
2626 enum action_executor_status executor_status
;
2627 const uint64_t trigger_tracer_token
=
2628 state
->trigger_id
.next_tracer_token
++;
2632 /* Set the trigger's tracer token. */
2633 lttng_trigger_set_tracer_token(trigger
, trigger_tracer_token
);
2635 if (lttng_trigger_get_name(trigger
, &trigger_name
) ==
2636 LTTNG_TRIGGER_STATUS_UNSET
) {
2637 const enum lttng_error_code ret_code
= generate_trigger_name(
2638 state
, trigger
, &trigger_name
);
2640 if (ret_code
!= LTTNG_OK
) {
2643 *cmd_result
= ret_code
;
2646 } else if (trigger_name_taken(state
, trigger
)) {
2647 /* Not a fatal error. */
2648 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2653 condition
= lttng_trigger_get_condition(trigger
);
2656 /* Some conditions require tracers to implement a minimal ABI version. */
2657 if (!condition_is_supported(condition
)) {
2658 *cmd_result
= LTTNG_ERR_NOT_SUPPORTED
;
2662 trigger_ht_element
= zmalloc(sizeof(*trigger_ht_element
));
2663 if (!trigger_ht_element
) {
2668 /* Add trigger to the trigger_ht. */
2669 cds_lfht_node_init(&trigger_ht_element
->node
);
2670 cds_lfht_node_init(&trigger_ht_element
->node_by_name_uid
);
2671 trigger_ht_element
->trigger
= trigger
;
2673 node
= cds_lfht_add_unique(state
->triggers_ht
,
2674 lttng_condition_hash(condition
),
2677 &trigger_ht_element
->node
);
2678 if (node
!= &trigger_ht_element
->node
) {
2679 /* Not a fatal error, simply report it to the client. */
2680 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2681 goto error_free_ht_element
;
2684 node
= cds_lfht_add_unique(state
->triggers_by_name_uid_ht
,
2685 hash_trigger_by_name_uid(trigger
),
2686 match_trigger_by_name_uid
,
2688 &trigger_ht_element
->node_by_name_uid
);
2689 if (node
!= &trigger_ht_element
->node_by_name_uid
) {
2690 /* Not a fatal error, simply report it to the client. */
2691 cds_lfht_del(state
->triggers_ht
, &trigger_ht_element
->node
);
2692 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2693 goto error_free_ht_element
;
2696 /* From this point consider the trigger registered. */
2697 lttng_trigger_set_as_registered(trigger
);
2700 * Some triggers might need a tracer notifier depending on its
2701 * condition and actions.
2703 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
2704 enum lttng_error_code error_code
;
2706 error_code
= setup_tracer_notifier(state
, trigger
);
2707 if (error_code
!= LTTNG_OK
) {
2708 notif_thread_state_remove_trigger_ht_elem(state
,
2709 trigger_ht_element
);
2710 if (error_code
== LTTNG_ERR_NOMEM
) {
2713 *cmd_result
= error_code
;
2717 goto error_free_ht_element
;
2722 * The rest only applies to triggers that have a "notify" action.
2723 * It is not skipped as this is the only action type currently
2726 if (is_trigger_action_notify(trigger
)) {
2728 * Find or create the client list of this condition. It may
2729 * already be present if another trigger is already registered
2730 * with the same condition.
2732 client_list
= get_client_list_from_condition(state
, condition
);
2735 * No client list for this condition yet. We create new
2736 * one and build it up.
2738 client_list
= notification_client_list_create(state
, condition
);
2740 ERR("Error creating notification client list for trigger %s", trigger
->name
);
2741 goto error_free_ht_element
;
2745 CDS_INIT_LIST_HEAD(&trigger_ht_element
->client_list_trigger_node
);
2747 pthread_mutex_lock(&client_list
->lock
);
2748 cds_list_add(&trigger_ht_element
->client_list_trigger_node
, &client_list
->triggers_list
);
2749 pthread_mutex_unlock(&client_list
->lock
);
2753 * Ownership of the trigger and of its wrapper was transfered to
2754 * the triggers_ht. Same for token ht element if necessary.
2756 trigger_ht_element
= NULL
;
2757 free_trigger
= false;
2759 switch (get_condition_binding_object(condition
)) {
2760 case LTTNG_OBJECT_TYPE_SESSION
:
2761 /* Add the trigger to the list if it matches a known session. */
2762 ret
= bind_trigger_to_matching_session(trigger
, state
);
2764 goto error_free_ht_element
;
2767 case LTTNG_OBJECT_TYPE_CHANNEL
:
2769 * Add the trigger to list of triggers bound to the channels
2772 ret
= bind_trigger_to_matching_channels(trigger
, state
);
2774 goto error_free_ht_element
;
2777 case LTTNG_OBJECT_TYPE_NONE
:
2780 ERR("Unknown object type on which to bind a newly registered trigger was encountered");
2782 goto error_free_ht_element
;
2786 * The new trigger's condition must be evaluated against the current
2789 * In the case of `notify` action, nothing preventing clients from
2790 * subscribing to a condition before the corresponding trigger is
2791 * registered, we have to evaluate this new condition right away.
2793 * At some point, we were waiting for the next "evaluation" (e.g. on
2794 * reception of a channel sample) to evaluate this new condition, but
2797 * The reason it was broken is that waiting for the next sample
2798 * does not allow us to properly handle transitions for edge-triggered
2801 * Consider this example: when we handle a new channel sample, we
2802 * evaluate each conditions twice: once with the previous state, and
2803 * again with the newest state. We then use those two results to
2804 * determine whether a state change happened: a condition was false and
2805 * became true. If a state change happened, we have to notify clients.
2807 * Now, if a client subscribes to a given notification and registers
2808 * a trigger *after* that subscription, we have to make sure the
2809 * condition is evaluated at this point while considering only the
2810 * current state. Otherwise, the next evaluation cycle may only see
2811 * that the evaluations remain the same (true for samples n-1 and n) and
2812 * the client will never know that the condition has been met.
2814 switch (get_condition_binding_object(condition
)) {
2815 case LTTNG_OBJECT_TYPE_SESSION
:
2816 ret
= evaluate_session_condition_for_client(condition
, state
,
2817 &evaluation
, &object_uid
,
2819 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2820 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2822 case LTTNG_OBJECT_TYPE_CHANNEL
:
2823 ret
= evaluate_channel_condition_for_client(condition
, state
,
2824 &evaluation
, &object_uid
,
2826 LTTNG_OPTIONAL_SET(&object_creds
.uid
, object_uid
);
2827 LTTNG_OPTIONAL_SET(&object_creds
.gid
, object_gid
);
2829 case LTTNG_OBJECT_TYPE_NONE
:
2832 case LTTNG_OBJECT_TYPE_UNKNOWN
:
2840 goto error_free_ht_element
;
2843 DBG("Newly registered trigger's condition evaluated to %s",
2844 evaluation
? "true" : "false");
2846 /* Evaluation yielded nothing. Normal exit. */
2852 * Ownership of `evaluation` transferred to the action executor
2853 * no matter the result.
2855 executor_status
= action_executor_enqueue(state
->executor
, trigger
,
2856 evaluation
, &object_creds
, client_list
);
2858 switch (executor_status
) {
2859 case ACTION_EXECUTOR_STATUS_OK
:
2861 case ACTION_EXECUTOR_STATUS_ERROR
:
2862 case ACTION_EXECUTOR_STATUS_INVALID
:
2864 * TODO Add trigger identification (name/id) when
2865 * it is added to the API.
2867 ERR("Fatal error occurred while enqueuing action associated to newly registered trigger");
2869 goto error_free_ht_element
;
2870 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
2872 * TODO Add trigger identification (name/id) when
2873 * it is added to the API.
2875 * Not a fatal error.
2877 WARN("No space left when enqueuing action associated to newly registered trigger");
2885 *cmd_result
= LTTNG_OK
;
2886 DBG("Registered trigger: name = `%s`, tracer token = %" PRIu64
,
2887 trigger_name
, trigger_tracer_token
);
2890 error_free_ht_element
:
2891 if (trigger_ht_element
) {
2892 /* Delayed removal due to RCU constraint on delete. */
2893 call_rcu(&trigger_ht_element
->rcu_node
,
2894 free_lttng_trigger_ht_element_rcu
);
2899 * Other objects might have a reference to the trigger, mark it
2902 lttng_trigger_set_as_unregistered(trigger
);
2903 lttng_trigger_destroy(trigger
);
2911 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
)
2913 free(caa_container_of(node
, struct lttng_trigger_ht_element
,
2918 void free_notification_trigger_tokens_ht_element_rcu(struct rcu_head
*node
)
2920 free(caa_container_of(node
, struct notification_trigger_tokens_ht_element
,
2925 void teardown_tracer_notifier(struct notification_thread_state
*state
,
2926 const struct lttng_trigger
*trigger
)
2928 struct cds_lfht_iter iter
;
2929 struct notification_trigger_tokens_ht_element
*trigger_tokens_ht_element
;
2931 cds_lfht_for_each_entry(state
->trigger_tokens_ht
, &iter
,
2932 trigger_tokens_ht_element
, node
) {
2934 if (!lttng_trigger_is_equal(trigger
,
2935 trigger_tokens_ht_element
->trigger
)) {
2939 event_notifier_error_accounting_unregister_event_notifier(
2940 trigger_tokens_ht_element
->trigger
);
2942 /* TODO talk to all app and remove it */
2943 DBG("[notification-thread] Removed trigger from tokens_ht");
2944 cds_lfht_del(state
->trigger_tokens_ht
,
2945 &trigger_tokens_ht_element
->node
);
2947 call_rcu(&trigger_tokens_ht_element
->rcu_node
,
2948 free_notification_trigger_tokens_ht_element_rcu
);
2955 int handle_notification_thread_command_unregister_trigger(
2956 struct notification_thread_state
*state
,
2957 const struct lttng_trigger
*trigger
,
2958 enum lttng_error_code
*_cmd_reply
)
2960 struct cds_lfht_iter iter
;
2961 struct cds_lfht_node
*triggers_ht_node
;
2962 struct lttng_channel_trigger_list
*trigger_list
;
2963 struct notification_client_list
*client_list
;
2964 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2965 const struct lttng_condition
*condition
= lttng_trigger_get_const_condition(
2967 enum lttng_error_code cmd_reply
;
2971 cds_lfht_lookup(state
->triggers_ht
,
2972 lttng_condition_hash(condition
),
2976 triggers_ht_node
= cds_lfht_iter_get_node(&iter
);
2977 if (!triggers_ht_node
) {
2978 cmd_reply
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
2981 cmd_reply
= LTTNG_OK
;
2984 trigger_ht_element
= caa_container_of(triggers_ht_node
,
2985 struct lttng_trigger_ht_element
, node
);
2987 /* From this point, consider the trigger unregistered no matter what. */
2988 lttng_trigger_set_as_unregistered(trigger_ht_element
->trigger
);
2990 /* Remove trigger from channel_triggers_ht. */
2991 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
, trigger_list
,
2992 channel_triggers_ht_node
) {
2993 struct lttng_trigger_list_element
*trigger_element
, *tmp
;
2995 cds_list_for_each_entry_safe(trigger_element
, tmp
,
2996 &trigger_list
->list
, node
) {
2997 if (!lttng_trigger_is_equal(trigger
, trigger_element
->trigger
)) {
3001 DBG("[notification-thread] Removed trigger from channel_triggers_ht");
3002 cds_list_del(&trigger_element
->node
);
3003 /* A trigger can only appear once per channel */
3008 if (lttng_trigger_needs_tracer_notifier(trigger
)) {
3009 teardown_tracer_notifier(state
, trigger
);
3012 if (is_trigger_action_notify(trigger
)) {
3014 * Remove and release the client list from
3015 * notification_trigger_clients_ht.
3017 client_list
= get_client_list_from_condition(state
, condition
);
3018 assert(client_list
);
3020 pthread_mutex_lock(&client_list
->lock
);
3021 cds_list_del(&trigger_ht_element
->client_list_trigger_node
);
3022 pthread_mutex_unlock(&client_list
->lock
);
3024 /* Put new reference and the hashtable's reference. */
3025 notification_client_list_put(client_list
);
3026 notification_client_list_put(client_list
);
3030 /* Remove trigger from triggers_ht. */
3031 notif_thread_state_remove_trigger_ht_elem(state
, trigger_ht_element
);
3033 /* Release the ownership of the trigger. */
3034 lttng_trigger_destroy(trigger_ht_element
->trigger
);
3035 call_rcu(&trigger_ht_element
->rcu_node
, free_lttng_trigger_ht_element_rcu
);
3039 *_cmd_reply
= cmd_reply
;
3044 /* Returns 0 on success, 1 on exit requested, negative value on error. */
3045 int handle_notification_thread_command(
3046 struct notification_thread_handle
*handle
,
3047 struct notification_thread_state
*state
)
3051 struct notification_thread_command
*cmd
;
3053 /* Read the event pipe to put it back into a quiescent state. */
3054 ret
= lttng_read(lttng_pipe_get_readfd(handle
->cmd_queue
.event_pipe
), &counter
,
3056 if (ret
!= sizeof(counter
)) {
3060 pthread_mutex_lock(&handle
->cmd_queue
.lock
);
3061 cmd
= cds_list_first_entry(&handle
->cmd_queue
.list
,
3062 struct notification_thread_command
, cmd_list_node
);
3063 cds_list_del(&cmd
->cmd_list_node
);
3064 pthread_mutex_unlock(&handle
->cmd_queue
.lock
);
3066 DBG("[notification-thread] Received `%s` command",
3067 notification_command_type_str(cmd
->type
));
3068 switch (cmd
->type
) {
3069 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
3070 ret
= handle_notification_thread_command_register_trigger(state
,
3071 cmd
->parameters
.register_trigger
.trigger
,
3074 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
3075 ret
= handle_notification_thread_command_unregister_trigger(
3077 cmd
->parameters
.unregister_trigger
.trigger
,
3080 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
3081 ret
= handle_notification_thread_command_add_channel(
3083 cmd
->parameters
.add_channel
.session
.name
,
3084 cmd
->parameters
.add_channel
.session
.uid
,
3085 cmd
->parameters
.add_channel
.session
.gid
,
3086 cmd
->parameters
.add_channel
.channel
.name
,
3087 cmd
->parameters
.add_channel
.channel
.domain
,
3088 cmd
->parameters
.add_channel
.channel
.key
,
3089 cmd
->parameters
.add_channel
.channel
.capacity
,
3092 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
3093 ret
= handle_notification_thread_command_remove_channel(
3094 state
, cmd
->parameters
.remove_channel
.key
,
3095 cmd
->parameters
.remove_channel
.domain
,
3098 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
3099 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
3100 ret
= handle_notification_thread_command_session_rotation(
3103 cmd
->parameters
.session_rotation
.session_name
,
3104 cmd
->parameters
.session_rotation
.uid
,
3105 cmd
->parameters
.session_rotation
.gid
,
3106 cmd
->parameters
.session_rotation
.trace_archive_chunk_id
,
3107 cmd
->parameters
.session_rotation
.location
,
3110 case NOTIFICATION_COMMAND_TYPE_ADD_TRACER_EVENT_SOURCE
:
3111 ret
= handle_notification_thread_command_add_tracer_event_source(
3113 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3114 cmd
->parameters
.tracer_event_source
.domain
,
3117 case NOTIFICATION_COMMAND_TYPE_REMOVE_TRACER_EVENT_SOURCE
:
3118 ret
= handle_notification_thread_command_remove_tracer_event_source(
3120 cmd
->parameters
.tracer_event_source
.tracer_event_source_fd
,
3123 case NOTIFICATION_COMMAND_TYPE_LIST_TRIGGERS
:
3125 struct lttng_triggers
*triggers
= NULL
;
3127 ret
= handle_notification_thread_command_list_triggers(
3130 cmd
->parameters
.list_triggers
.uid
,
3133 cmd
->reply
.list_triggers
.triggers
= triggers
;
3137 case NOTIFICATION_COMMAND_TYPE_QUIT
:
3138 cmd
->reply_code
= LTTNG_OK
;
3141 case NOTIFICATION_COMMAND_TYPE_CLIENT_COMMUNICATION_UPDATE
:
3143 const enum client_transmission_status client_status
=
3144 cmd
->parameters
.client_communication_update
3146 const notification_client_id client_id
=
3147 cmd
->parameters
.client_communication_update
.id
;
3148 struct notification_client
*client
;
3151 client
= get_client_from_id(client_id
, state
);
3155 * Client error was probably already picked-up by the
3156 * notification thread or it has disconnected
3157 * gracefully while this command was queued.
3159 DBG("Failed to find notification client to update communication status, client id = %" PRIu64
,
3163 ret
= client_handle_transmission_status(
3164 client
, client_status
, state
);
3170 ERR("[notification-thread] Unknown internal command received");
3178 if (cmd
->is_async
) {
3182 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3186 /* Wake-up and return a fatal error to the calling thread. */
3187 lttng_waiter_wake_up(&cmd
->reply_waiter
);
3188 cmd
->reply_code
= LTTNG_ERR_FATAL
;
3190 /* Indicate a fatal error to the caller. */
3195 int socket_set_non_blocking(int socket
)
3199 /* Set the pipe as non-blocking. */
3200 ret
= fcntl(socket
, F_GETFL
, 0);
3202 PERROR("fcntl get socket flags");
3207 ret
= fcntl(socket
, F_SETFL
, flags
| O_NONBLOCK
);
3209 PERROR("fcntl set O_NONBLOCK socket flag");
3212 DBG("Client socket (fd = %i) set as non-blocking", socket
);
3218 int client_reset_inbound_state(struct notification_client
*client
)
3223 lttng_payload_clear(&client
->communication
.inbound
.payload
);
3225 client
->communication
.inbound
.bytes_to_receive
=
3226 sizeof(struct lttng_notification_channel_message
);
3227 client
->communication
.inbound
.msg_type
=
3228 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
;
3229 LTTNG_SOCK_SET_UID_CRED(&client
->communication
.inbound
.creds
, -1);
3230 LTTNG_SOCK_SET_GID_CRED(&client
->communication
.inbound
.creds
, -1);
3231 ret
= lttng_dynamic_buffer_set_size(
3232 &client
->communication
.inbound
.payload
.buffer
,
3233 client
->communication
.inbound
.bytes_to_receive
);
3238 int handle_notification_thread_client_connect(
3239 struct notification_thread_state
*state
)
3242 struct notification_client
*client
;
3244 DBG("[notification-thread] Handling new notification channel client connection");
3246 client
= zmalloc(sizeof(*client
));
3253 pthread_mutex_init(&client
->lock
, NULL
);
3254 client
->id
= state
->next_notification_client_id
++;
3255 CDS_INIT_LIST_HEAD(&client
->condition_list
);
3256 lttng_payload_init(&client
->communication
.inbound
.payload
);
3257 lttng_payload_init(&client
->communication
.outbound
.payload
);
3258 client
->communication
.inbound
.expect_creds
= true;
3260 ret
= client_reset_inbound_state(client
);
3262 ERR("[notification-thread] Failed to reset client communication's inbound state");
3267 ret
= lttcomm_accept_unix_sock(state
->notification_channel_socket
);
3269 ERR("[notification-thread] Failed to accept new notification channel client connection");
3274 client
->socket
= ret
;
3276 ret
= socket_set_non_blocking(client
->socket
);
3278 ERR("[notification-thread] Failed to set new notification channel client connection socket as non-blocking");
3282 ret
= lttcomm_setsockopt_creds_unix_sock(client
->socket
);
3284 ERR("[notification-thread] Failed to set socket options on new notification channel client socket");
3289 ret
= lttng_poll_add(&state
->events
, client
->socket
,
3290 LPOLLIN
| LPOLLERR
|
3291 LPOLLHUP
| LPOLLRDHUP
);
3293 ERR("[notification-thread] Failed to add notification channel client socket to poll set");
3297 DBG("[notification-thread] Added new notification channel client socket (%i) to poll set",
3301 cds_lfht_add(state
->client_socket_ht
,
3302 hash_client_socket(client
->socket
),
3303 &client
->client_socket_ht_node
);
3304 cds_lfht_add(state
->client_id_ht
,
3305 hash_client_id(client
->id
),
3306 &client
->client_id_ht_node
);
3312 notification_client_destroy(client
, state
);
3317 * RCU read-lock must be held by the caller.
3318 * Client lock must _not_ be held by the caller.
3321 int notification_thread_client_disconnect(
3322 struct notification_client
*client
,
3323 struct notification_thread_state
*state
)
3326 struct lttng_condition_list_element
*condition_list_element
, *tmp
;
3328 /* Acquire the client lock to disable its communication atomically. */
3329 pthread_mutex_lock(&client
->lock
);
3330 client
->communication
.active
= false;
3331 cds_lfht_del(state
->client_socket_ht
, &client
->client_socket_ht_node
);
3332 cds_lfht_del(state
->client_id_ht
, &client
->client_id_ht_node
);
3333 pthread_mutex_unlock(&client
->lock
);
3335 ret
= lttng_poll_del(&state
->events
, client
->socket
);
3337 ERR("[notification-thread] Failed to remove client socket %d from poll set",
3341 /* Release all conditions to which the client was subscribed. */
3342 cds_list_for_each_entry_safe(condition_list_element
, tmp
,
3343 &client
->condition_list
, node
) {
3344 (void) notification_thread_client_unsubscribe(client
,
3345 condition_list_element
->condition
, state
, NULL
);
3349 * Client no longer accessible to other threads (through the
3352 notification_client_destroy(client
, state
);
3356 int handle_notification_thread_client_disconnect(
3357 int client_socket
, struct notification_thread_state
*state
)
3360 struct notification_client
*client
;
3363 DBG("[notification-thread] Closing client connection (socket fd = %i)",
3365 client
= get_client_from_socket(client_socket
, state
);
3367 /* Internal state corruption, fatal error. */
3368 ERR("[notification-thread] Unable to find client (socket fd = %i)",
3374 ret
= notification_thread_client_disconnect(client
, state
);
3380 int handle_notification_thread_client_disconnect_all(
3381 struct notification_thread_state
*state
)
3383 struct cds_lfht_iter iter
;
3384 struct notification_client
*client
;
3385 bool error_encoutered
= false;
3388 DBG("[notification-thread] Closing all client connections");
3389 cds_lfht_for_each_entry(state
->client_socket_ht
, &iter
, client
,
3390 client_socket_ht_node
) {
3393 ret
= notification_thread_client_disconnect(
3396 error_encoutered
= true;
3400 return error_encoutered
? 1 : 0;
3403 int handle_notification_thread_trigger_unregister_all(
3404 struct notification_thread_state
*state
)
3406 bool error_occurred
= false;
3407 struct cds_lfht_iter iter
;
3408 struct lttng_trigger_ht_element
*trigger_ht_element
;
3411 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
3413 int ret
= handle_notification_thread_command_unregister_trigger(
3414 state
, trigger_ht_element
->trigger
, NULL
);
3416 error_occurred
= true;
3420 return error_occurred
? -1 : 0;
3424 int client_handle_transmission_status(
3425 struct notification_client
*client
,
3426 enum client_transmission_status transmission_status
,
3427 struct notification_thread_state
*state
)
3431 switch (transmission_status
) {
3432 case CLIENT_TRANSMISSION_STATUS_COMPLETE
:
3433 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3434 CLIENT_POLL_MASK_IN
);
3440 case CLIENT_TRANSMISSION_STATUS_QUEUED
:
3442 * We want to be notified whenever there is buffer space
3443 * available to send the rest of the payload.
3445 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
3446 CLIENT_POLL_MASK_IN_OUT
);
3451 case CLIENT_TRANSMISSION_STATUS_FAIL
:
3452 ret
= notification_thread_client_disconnect(client
, state
);
3457 case CLIENT_TRANSMISSION_STATUS_ERROR
:
3467 /* Client lock must be acquired by caller. */
3469 enum client_transmission_status
client_flush_outgoing_queue(
3470 struct notification_client
*client
)
3473 size_t to_send_count
;
3474 enum client_transmission_status status
;
3475 struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3476 &client
->communication
.outbound
.payload
, 0, -1);
3477 const int fds_to_send_count
=
3478 lttng_payload_view_get_fd_handle_count(&pv
);
3480 ASSERT_LOCKED(client
->lock
);
3482 if (!client
->communication
.active
) {
3483 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3487 if (pv
.buffer
.size
== 0) {
3489 * If both data and fds are equal to zero, we are in an invalid
3492 assert(fds_to_send_count
!= 0);
3497 to_send_count
= pv
.buffer
.size
;
3498 DBG("[notification-thread] Flushing client (socket fd = %i) outgoing queue",
3501 ret
= lttcomm_send_unix_sock_non_block(client
->socket
,
3504 if ((ret
>= 0 && ret
< to_send_count
)) {
3505 DBG("[notification-thread] Client (socket fd = %i) outgoing queue could not be completely flushed",
3507 to_send_count
-= max(ret
, 0);
3509 memmove(client
->communication
.outbound
.payload
.buffer
.data
,
3511 pv
.buffer
.size
- to_send_count
,
3513 ret
= lttng_dynamic_buffer_set_size(
3514 &client
->communication
.outbound
.payload
.buffer
,
3520 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3522 } else if (ret
< 0) {
3523 /* Generic error, disable the client's communication. */
3524 ERR("[notification-thread] Failed to flush outgoing queue, disconnecting client (socket fd = %i)",
3526 client
->communication
.active
= false;
3527 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3531 * No error and flushed the queue completely.
3533 * The payload buffer size is used later to
3534 * check if there is notifications queued. So albeit that the
3535 * direct caller knows that the transmission is complete, we
3536 * need to set the buffer size to zero.
3538 ret
= lttng_dynamic_buffer_set_size(
3539 &client
->communication
.outbound
.payload
.buffer
, 0);
3546 /* No fds to send, transmission is complete. */
3547 if (fds_to_send_count
== 0) {
3548 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3552 ret
= lttcomm_send_payload_view_fds_unix_sock_non_block(
3553 client
->socket
, &pv
);
3555 /* Generic error, disable the client's communication. */
3556 ERR("[notification-thread] Failed to flush outgoing fds queue, disconnecting client (socket fd = %i)",
3558 client
->communication
.active
= false;
3559 status
= CLIENT_TRANSMISSION_STATUS_FAIL
;
3561 } else if (ret
== 0) {
3562 /* Nothing could be sent. */
3563 status
= CLIENT_TRANSMISSION_STATUS_QUEUED
;
3565 /* Fd passing is an all or nothing kind of thing. */
3566 status
= CLIENT_TRANSMISSION_STATUS_COMPLETE
;
3568 * The payload _fd_array count is used later to
3569 * check if there is notifications queued. So although the
3570 * direct caller knows that the transmission is complete, we
3571 * need to clear the _fd_array for the queuing check.
3573 lttng_dynamic_pointer_array_clear(
3574 &client
->communication
.outbound
.payload
3579 if (status
== CLIENT_TRANSMISSION_STATUS_COMPLETE
) {
3580 client
->communication
.outbound
.queued_command_reply
= false;
3581 client
->communication
.outbound
.dropped_notification
= false;
3582 lttng_payload_clear(&client
->communication
.outbound
.payload
);
3587 return CLIENT_TRANSMISSION_STATUS_ERROR
;
3591 bool client_has_outbound_data_left(
3592 const struct notification_client
*client
)
3594 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
3595 &client
->communication
.outbound
.payload
, 0, -1);
3596 const bool has_data
= pv
.buffer
.size
!= 0;
3597 const bool has_fds
= lttng_payload_view_get_fd_handle_count(&pv
);
3599 return has_data
|| has_fds
;
3602 /* Client lock must _not_ be held by the caller. */
3604 int client_send_command_reply(struct notification_client
*client
,
3605 struct notification_thread_state
*state
,
3606 enum lttng_notification_channel_status status
)
3609 struct lttng_notification_channel_command_reply reply
= {
3610 .status
= (int8_t) status
,
3612 struct lttng_notification_channel_message msg
= {
3613 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY
,
3614 .size
= sizeof(reply
),
3616 char buffer
[sizeof(msg
) + sizeof(reply
)];
3617 enum client_transmission_status transmission_status
;
3619 memcpy(buffer
, &msg
, sizeof(msg
));
3620 memcpy(buffer
+ sizeof(msg
), &reply
, sizeof(reply
));
3621 DBG("[notification-thread] Send command reply (%i)", (int) status
);
3623 pthread_mutex_lock(&client
->lock
);
3624 if (client
->communication
.outbound
.queued_command_reply
) {
3625 /* Protocol error. */
3629 /* Enqueue buffer to outgoing queue and flush it. */
3630 ret
= lttng_dynamic_buffer_append(
3631 &client
->communication
.outbound
.payload
.buffer
,
3632 buffer
, sizeof(buffer
));
3637 transmission_status
= client_flush_outgoing_queue(client
);
3639 if (client_has_outbound_data_left(client
)) {
3640 /* Queue could not be emptied. */
3641 client
->communication
.outbound
.queued_command_reply
= true;
3644 pthread_mutex_unlock(&client
->lock
);
3645 ret
= client_handle_transmission_status(
3646 client
, transmission_status
, state
);
3653 pthread_mutex_unlock(&client
->lock
);
3659 int client_handle_message_unknown(struct notification_client
*client
,
3660 struct notification_thread_state
*state
)
3664 * Receiving message header. The function will be called again
3665 * once the rest of the message as been received and can be
3668 const struct lttng_notification_channel_message
*msg
;
3670 assert(sizeof(*msg
) == client
->communication
.inbound
.payload
.buffer
.size
);
3671 msg
= (const struct lttng_notification_channel_message
*)
3672 client
->communication
.inbound
.payload
.buffer
.data
;
3674 if (msg
->size
== 0 ||
3675 msg
->size
> DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE
) {
3676 ERR("[notification-thread] Invalid notification channel message: length = %u",
3682 switch (msg
->type
) {
3683 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3684 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3685 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3689 ERR("[notification-thread] Invalid notification channel message: unexpected message type");
3693 client
->communication
.inbound
.bytes_to_receive
= msg
->size
;
3694 client
->communication
.inbound
.fds_to_receive
= msg
->fds
;
3695 client
->communication
.inbound
.msg_type
=
3696 (enum lttng_notification_channel_message_type
) msg
->type
;
3697 ret
= lttng_dynamic_buffer_set_size(
3698 &client
->communication
.inbound
.payload
.buffer
, msg
->size
);
3700 /* msg is not valid anymore due to lttng_dynamic_buffer_set_size. */
3707 int client_handle_message_handshake(struct notification_client
*client
,
3708 struct notification_thread_state
*state
)
3711 struct lttng_notification_channel_command_handshake
*handshake_client
;
3712 const struct lttng_notification_channel_command_handshake handshake_reply
= {
3713 .major
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
,
3714 .minor
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR
,
3716 const struct lttng_notification_channel_message msg_header
= {
3717 .type
= LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
,
3718 .size
= sizeof(handshake_reply
),
3720 enum lttng_notification_channel_status status
=
3721 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3722 char send_buffer
[sizeof(msg_header
) + sizeof(handshake_reply
)];
3724 memcpy(send_buffer
, &msg_header
, sizeof(msg_header
));
3725 memcpy(send_buffer
+ sizeof(msg_header
), &handshake_reply
,
3726 sizeof(handshake_reply
));
3729 (struct lttng_notification_channel_command_handshake
*)
3730 client
->communication
.inbound
.payload
.buffer
3732 client
->major
= handshake_client
->major
;
3733 client
->minor
= handshake_client
->minor
;
3734 if (!client
->communication
.inbound
.creds_received
) {
3735 ERR("[notification-thread] No credentials received from client");
3740 client
->uid
= LTTNG_SOCK_GET_UID_CRED(
3741 &client
->communication
.inbound
.creds
);
3742 client
->gid
= LTTNG_SOCK_GET_GID_CRED(
3743 &client
->communication
.inbound
.creds
);
3744 DBG("[notification-thread] Received handshake from client (uid = %u, gid = %u) with version %i.%i",
3745 client
->uid
, client
->gid
, (int) client
->major
,
3746 (int) client
->minor
);
3748 if (handshake_client
->major
!=
3749 LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
) {
3750 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION
;
3753 pthread_mutex_lock(&client
->lock
);
3754 /* Outgoing queue will be flushed when the command reply is sent. */
3755 ret
= lttng_dynamic_buffer_append(
3756 &client
->communication
.outbound
.payload
.buffer
, send_buffer
,
3757 sizeof(send_buffer
));
3759 ERR("[notification-thread] Failed to send protocol version to notification channel client");
3763 client
->validated
= true;
3764 client
->communication
.active
= true;
3765 pthread_mutex_unlock(&client
->lock
);
3767 /* Set reception state to receive the next message header. */
3768 ret
= client_reset_inbound_state(client
);
3770 ERR("[notification-thread] Failed to reset client communication's inbound state");
3774 /* Flushes the outgoing queue. */
3775 ret
= client_send_command_reply(client
, state
, status
);
3777 ERR("[notification-thread] Failed to send reply to notification channel client");
3783 pthread_mutex_unlock(&client
->lock
);
3789 int client_handle_message_subscription(
3790 struct notification_client
*client
,
3791 enum lttng_notification_channel_message_type msg_type
,
3792 struct notification_thread_state
*state
)
3795 struct lttng_condition
*condition
;
3796 enum lttng_notification_channel_status status
=
3797 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
3798 struct lttng_payload_view condition_view
=
3799 lttng_payload_view_from_payload(
3800 &client
->communication
.inbound
.payload
,
3802 size_t expected_condition_size
;
3805 * No need to lock client to sample the inbound state as the only
3806 * other thread accessing clients (action executor) only uses the
3809 expected_condition_size
= client
->communication
.inbound
.payload
.buffer
.size
;
3810 ret
= lttng_condition_create_from_payload(&condition_view
, &condition
);
3811 if (ret
!= expected_condition_size
) {
3812 ERR("[notification-thread] Malformed condition received from client");
3816 if (msg_type
== LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
) {
3817 ret
= notification_thread_client_subscribe(
3818 client
, condition
, state
, &status
);
3820 ret
= notification_thread_client_unsubscribe(
3821 client
, condition
, state
, &status
);
3828 /* Set reception state to receive the next message header. */
3829 ret
= client_reset_inbound_state(client
);
3831 ERR("[notification-thread] Failed to reset client communication's inbound state");
3835 ret
= client_send_command_reply(client
, state
, status
);
3837 ERR("[notification-thread] Failed to send reply to notification channel client");
3846 int client_dispatch_message(struct notification_client
*client
,
3847 struct notification_thread_state
*state
)
3851 if (client
->communication
.inbound
.msg_type
!=
3852 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
&&
3853 client
->communication
.inbound
.msg_type
!=
3854 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
&&
3855 !client
->validated
) {
3856 WARN("[notification-thread] client attempted a command before handshake");
3861 switch (client
->communication
.inbound
.msg_type
) {
3862 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
:
3864 ret
= client_handle_message_unknown(client
, state
);
3867 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
3869 ret
= client_handle_message_handshake(client
, state
);
3872 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
3873 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
3875 ret
= client_handle_message_subscription(client
,
3876 client
->communication
.inbound
.msg_type
, state
);
3886 /* Incoming data from client. */
3887 int handle_notification_thread_client_in(
3888 struct notification_thread_state
*state
, int socket
)
3891 struct notification_client
*client
;
3896 client
= get_client_from_socket(socket
, state
);
3898 /* Internal error, abort. */
3903 offset
= client
->communication
.inbound
.payload
.buffer
.size
-
3904 client
->communication
.inbound
.bytes_to_receive
;
3905 if (client
->communication
.inbound
.expect_creds
) {
3906 recv_ret
= lttcomm_recv_creds_unix_sock(socket
,
3907 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
3908 client
->communication
.inbound
.bytes_to_receive
,
3909 &client
->communication
.inbound
.creds
);
3911 client
->communication
.inbound
.expect_creds
= false;
3912 client
->communication
.inbound
.creds_received
= true;
3915 recv_ret
= lttcomm_recv_unix_sock_non_block(socket
,
3916 client
->communication
.inbound
.payload
.buffer
.data
+ offset
,
3917 client
->communication
.inbound
.bytes_to_receive
);
3919 if (recv_ret
>= 0) {
3920 client
->communication
.inbound
.bytes_to_receive
-= recv_ret
;
3922 goto error_disconnect_client
;
3925 if (client
->communication
.inbound
.bytes_to_receive
!= 0) {
3926 /* Message incomplete wait for more data. */
3931 assert(client
->communication
.inbound
.bytes_to_receive
== 0);
3934 if (client
->communication
.inbound
.fds_to_receive
!= 0) {
3935 ret
= lttcomm_recv_payload_fds_unix_sock_non_block(
3937 client
->communication
.inbound
.fds_to_receive
,
3938 &client
->communication
.inbound
.payload
);
3941 * Fds received. non blocking fds passing is all
3944 ssize_t expected_size
;
3946 expected_size
= sizeof(int) *
3947 client
->communication
.inbound
3949 assert(ret
== expected_size
);
3950 client
->communication
.inbound
.fds_to_receive
= 0;
3951 } else if (ret
== 0) {
3952 /* Received nothing. */
3956 goto error_disconnect_client
;
3960 /* At this point the message is complete.*/
3961 assert(client
->communication
.inbound
.bytes_to_receive
== 0 &&
3962 client
->communication
.inbound
.fds_to_receive
== 0);
3963 ret
= client_dispatch_message(client
, state
);
3966 * Only returns an error if this client must be
3969 goto error_disconnect_client
;
3976 error_disconnect_client
:
3977 ret
= notification_thread_client_disconnect(client
, state
);
3981 /* Client ready to receive outgoing data. */
3982 int handle_notification_thread_client_out(
3983 struct notification_thread_state
*state
, int socket
)
3986 struct notification_client
*client
;
3987 enum client_transmission_status transmission_status
;
3990 client
= get_client_from_socket(socket
, state
);
3992 /* Internal error, abort. */
3997 pthread_mutex_lock(&client
->lock
);
3998 transmission_status
= client_flush_outgoing_queue(client
);
3999 pthread_mutex_unlock(&client
->lock
);
4001 ret
= client_handle_transmission_status(
4002 client
, transmission_status
, state
);
4012 bool evaluate_buffer_usage_condition(const struct lttng_condition
*condition
,
4013 const struct channel_state_sample
*sample
,
4014 uint64_t buffer_capacity
)
4016 bool result
= false;
4018 enum lttng_condition_type condition_type
;
4019 const struct lttng_condition_buffer_usage
*use_condition
= container_of(
4020 condition
, struct lttng_condition_buffer_usage
,
4023 if (use_condition
->threshold_bytes
.set
) {
4024 threshold
= use_condition
->threshold_bytes
.value
;
4027 * Threshold was expressed as a ratio.
4029 * TODO the threshold (in bytes) of conditions expressed
4030 * as a ratio of total buffer size could be cached to
4031 * forego this double-multiplication or it could be performed
4032 * as fixed-point math.
4034 * Note that caching should accommodates the case where the
4035 * condition applies to multiple channels (i.e. don't assume
4036 * that all channels matching my_chann* have the same size...)
4038 threshold
= (uint64_t) (use_condition
->threshold_ratio
.value
*
4039 (double) buffer_capacity
);
4042 condition_type
= lttng_condition_get_type(condition
);
4043 if (condition_type
== LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
) {
4044 DBG("[notification-thread] Low buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4045 threshold
, sample
->highest_usage
);
4048 * The low condition should only be triggered once _all_ of the
4049 * streams in a channel have gone below the "low" threshold.
4051 if (sample
->highest_usage
<= threshold
) {
4055 DBG("[notification-thread] High buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
4056 threshold
, sample
->highest_usage
);
4059 * For high buffer usage scenarios, we want to trigger whenever
4060 * _any_ of the streams has reached the "high" threshold.
4062 if (sample
->highest_usage
>= threshold
) {
4071 bool evaluate_session_consumed_size_condition(
4072 const struct lttng_condition
*condition
,
4073 uint64_t session_consumed_size
)
4076 const struct lttng_condition_session_consumed_size
*size_condition
=
4077 container_of(condition
,
4078 struct lttng_condition_session_consumed_size
,
4081 threshold
= size_condition
->consumed_threshold_bytes
.value
;
4082 DBG("[notification-thread] Session consumed size condition being evaluated: threshold = %" PRIu64
", current size = %" PRIu64
,
4083 threshold
, session_consumed_size
);
4084 return session_consumed_size
>= threshold
;
4088 int evaluate_buffer_condition(const struct lttng_condition
*condition
,
4089 struct lttng_evaluation
**evaluation
,
4090 const struct notification_thread_state
*state
,
4091 const struct channel_state_sample
*previous_sample
,
4092 const struct channel_state_sample
*latest_sample
,
4093 uint64_t previous_session_consumed_total
,
4094 uint64_t latest_session_consumed_total
,
4095 struct channel_info
*channel_info
)
4098 enum lttng_condition_type condition_type
;
4099 const bool previous_sample_available
= !!previous_sample
;
4100 bool previous_sample_result
= false;
4101 bool latest_sample_result
;
4103 condition_type
= lttng_condition_get_type(condition
);
4105 switch (condition_type
) {
4106 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4107 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4108 if (caa_likely(previous_sample_available
)) {
4109 previous_sample_result
=
4110 evaluate_buffer_usage_condition(condition
,
4111 previous_sample
, channel_info
->capacity
);
4113 latest_sample_result
= evaluate_buffer_usage_condition(
4114 condition
, latest_sample
,
4115 channel_info
->capacity
);
4117 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
4118 if (caa_likely(previous_sample_available
)) {
4119 previous_sample_result
=
4120 evaluate_session_consumed_size_condition(
4122 previous_session_consumed_total
);
4124 latest_sample_result
=
4125 evaluate_session_consumed_size_condition(
4127 latest_session_consumed_total
);
4130 /* Unknown condition type; internal error. */
4134 if (!latest_sample_result
||
4135 (previous_sample_result
== latest_sample_result
)) {
4137 * Only trigger on a condition evaluation transition.
4139 * NOTE: This edge-triggered logic may not be appropriate for
4140 * future condition types.
4145 if (!evaluation
|| !latest_sample_result
) {
4149 switch (condition_type
) {
4150 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
4151 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
4152 *evaluation
= lttng_evaluation_buffer_usage_create(
4154 latest_sample
->highest_usage
,
4155 channel_info
->capacity
);
4157 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
4158 *evaluation
= lttng_evaluation_session_consumed_size_create(
4159 latest_session_consumed_total
);
4174 int client_notification_overflow(struct notification_client
*client
)
4177 const struct lttng_notification_channel_message msg
= {
4178 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED
,
4181 ASSERT_LOCKED(client
->lock
);
4183 DBG("Dropping notification addressed to client (socket fd = %i)",
4185 if (client
->communication
.outbound
.dropped_notification
) {
4187 * The client already has a "notification dropped" message
4188 * in its outgoing queue. Nothing to do since all
4189 * of those messages are coalesced.
4194 client
->communication
.outbound
.dropped_notification
= true;
4195 ret
= lttng_dynamic_buffer_append(
4196 &client
->communication
.outbound
.payload
.buffer
, &msg
,
4199 PERROR("Failed to enqueue \"dropped notification\" message in client's (socket fd = %i) outgoing queue",
4206 static int client_handle_transmission_status_wrapper(
4207 struct notification_client
*client
,
4208 enum client_transmission_status status
,
4211 return client_handle_transmission_status(client
, status
,
4212 (struct notification_thread_state
*) user_data
);
4216 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
4217 const struct lttng_evaluation
*evaluation
,
4218 struct notification_client_list
* client_list
,
4219 struct notification_thread_state
*state
,
4220 uid_t object_uid
, gid_t object_gid
)
4222 const struct lttng_credentials creds
= {
4223 .uid
= LTTNG_OPTIONAL_INIT_VALUE(object_uid
),
4224 .gid
= LTTNG_OPTIONAL_INIT_VALUE(object_gid
),
4227 return notification_client_list_send_evaluation(client_list
,
4228 trigger
, evaluation
,
4230 client_handle_transmission_status_wrapper
, state
);
4234 * Permission checks relative to notification channel clients are performed
4235 * here. Notice how object, client, and trigger credentials are involved in
4238 * The `object` credentials are the credentials associated with the "subject"
4239 * of a condition. For instance, a `rotation completed` condition applies
4240 * to a session. When that condition is met, it will produce an evaluation
4241 * against a session. Hence, in this case, the `object` credentials are the
4242 * credentials of the "subject" session.
4244 * The `trigger` credentials are the credentials of the user that registered the
4247 * The `client` credentials are the credentials of the user that created a given
4248 * notification channel.
4250 * In terms of visibility, it is expected that non-privilieged users can only
4251 * register triggers against "their" objects (their own sessions and
4252 * applications they are allowed to interact with). They can then open a
4253 * notification channel and subscribe to notifications associated with those
4256 * As for privilieged users, they can register triggers against the objects of
4257 * other users. They can then subscribe to the notifications associated to their
4258 * triggers. Privilieged users _can't_ subscribe to the notifications of
4259 * triggers owned by other users; they must create their own triggers.
4261 * This is more a concern of usability than security. It would be difficult for
4262 * a root user reliably subscribe to a specific set of conditions without
4263 * interference from external users (those could, for instance, unregister
4267 int notification_client_list_send_evaluation(
4268 struct notification_client_list
*client_list
,
4269 const struct lttng_trigger
*trigger
,
4270 const struct lttng_evaluation
*evaluation
,
4271 const struct lttng_credentials
*source_object_creds
,
4272 report_client_transmission_result_cb client_report
,
4276 struct lttng_payload msg_payload
;
4277 struct notification_client_list_element
*client_list_element
, *tmp
;
4278 const struct lttng_notification notification
= {
4279 .trigger
= (struct lttng_trigger
*) trigger
,
4280 .evaluation
= (struct lttng_evaluation
*) evaluation
,
4282 struct lttng_notification_channel_message msg_header
= {
4283 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION
,
4285 const struct lttng_credentials
*trigger_creds
=
4286 lttng_trigger_get_credentials(trigger
);
4288 lttng_payload_init(&msg_payload
);
4290 ret
= lttng_dynamic_buffer_append(&msg_payload
.buffer
, &msg_header
,
4291 sizeof(msg_header
));
4296 ret
= lttng_notification_serialize(¬ification
, &msg_payload
);
4298 ERR("[notification-thread] Failed to serialize notification");
4303 /* Update payload size. */
4304 ((struct lttng_notification_channel_message
*) msg_payload
.buffer
.data
)
4305 ->size
= (uint32_t)(
4306 msg_payload
.buffer
.size
- sizeof(msg_header
));
4308 /* Update the payload number of fds. */
4310 const struct lttng_payload_view pv
= lttng_payload_view_from_payload(
4311 &msg_payload
, 0, -1);
4313 ((struct lttng_notification_channel_message
*)
4314 msg_payload
.buffer
.data
)->fds
= (uint32_t)
4315 lttng_payload_view_get_fd_handle_count(&pv
);
4318 pthread_mutex_lock(&client_list
->lock
);
4319 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4320 &client_list
->clients_list
, node
) {
4321 enum client_transmission_status transmission_status
;
4322 struct notification_client
*client
=
4323 client_list_element
->client
;
4326 pthread_mutex_lock(&client
->lock
);
4327 if (!client
->communication
.active
) {
4329 * Skip inactive client (protocol error or
4332 DBG("Skipping client at it is marked as inactive");
4336 if (source_object_creds
) {
4337 if (client
->uid
!= lttng_credentials_get_uid(source_object_creds
) &&
4338 client
->gid
!= lttng_credentials_get_gid(source_object_creds
) &&
4341 * Client is not allowed to monitor this
4344 DBG("[notification-thread] Skipping client at it does not have the object permission to receive notification for this trigger");
4349 if (client
->uid
!= lttng_credentials_get_uid(trigger_creds
)) {
4350 DBG("[notification-thread] Skipping client at it does not have the permission to receive notification for this trigger");
4354 DBG("[notification-thread] Sending notification to client (fd = %i, %zu bytes)",
4355 client
->socket
, msg_payload
.buffer
.size
);
4357 if (client_has_outbound_data_left(client
)) {
4359 * Outgoing data is already buffered for this client;
4360 * drop the notification and enqueue a "dropped
4361 * notification" message if this is the first dropped
4362 * notification since the socket spilled-over to the
4365 ret
= client_notification_overflow(client
);
4372 ret
= lttng_payload_copy(&msg_payload
, &client
->communication
.outbound
.payload
);
4378 transmission_status
= client_flush_outgoing_queue(client
);
4379 pthread_mutex_unlock(&client
->lock
);
4380 ret
= client_report(client
, transmission_status
, user_data
);
4383 goto end_unlock_list
;
4389 pthread_mutex_unlock(&client
->lock
);
4392 goto end_unlock_list
;
4398 pthread_mutex_unlock(&client_list
->lock
);
4400 lttng_payload_reset(&msg_payload
);
4405 struct lttng_event_notifier_notification
*recv_one_event_notifier_notification(
4406 int notification_pipe_read_fd
, enum lttng_domain_type domain
)
4410 struct lttng_event_notifier_notification
*notification
= NULL
;
4411 char *capture_buffer
= NULL
;
4412 size_t capture_buffer_size
;
4413 void *reception_buffer
;
4414 size_t reception_size
;
4416 struct lttng_ust_abi_event_notifier_notification ust_notification
;
4417 struct lttng_kernel_event_notifier_notification kernel_notification
;
4419 /* Init lttng_event_notifier_notification */
4421 case LTTNG_DOMAIN_UST
:
4422 reception_buffer
= (void *) &ust_notification
;
4423 reception_size
= sizeof(ust_notification
);
4425 case LTTNG_DOMAIN_KERNEL
:
4426 reception_buffer
= (void *) &kernel_notification
;
4427 reception_size
= sizeof(kernel_notification
);
4434 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4435 * ensuring that read/write of tracer notifications are atomic.
4437 ret
= lttng_read(notification_pipe_read_fd
, reception_buffer
,
4439 if (ret
!= reception_size
) {
4440 PERROR("Failed to read from event source notification pipe: fd = %d, size to read = %zu, ret = %d",
4441 notification_pipe_read_fd
, reception_size
, ret
);
4447 case LTTNG_DOMAIN_UST
:
4448 token
= ust_notification
.token
;
4449 capture_buffer_size
= ust_notification
.capture_buf_size
;
4451 case LTTNG_DOMAIN_KERNEL
:
4452 token
= kernel_notification
.token
;
4453 capture_buffer_size
= kernel_notification
.capture_buf_size
;
4459 if (capture_buffer_size
== 0) {
4460 capture_buffer
= NULL
;
4464 if (capture_buffer_size
> MAX_CAPTURE_SIZE
) {
4465 ERR("[notification-thread] Event notifier has a capture payload size which exceeds the maximum allowed size: capture_payload_size = %zu bytes, max allowed size = %d bytes",
4466 capture_buffer_size
, MAX_CAPTURE_SIZE
);
4470 capture_buffer
= zmalloc(capture_buffer_size
);
4471 if (!capture_buffer
) {
4472 ERR("[notification-thread] Failed to allocate capture buffer");
4476 /* Fetch additional payload (capture). */
4477 ret
= lttng_read(notification_pipe_read_fd
, capture_buffer
, capture_buffer_size
);
4478 if (ret
!= capture_buffer_size
) {
4479 ERR("[notification-thread] Failed to read from event source pipe (fd = %i)",
4480 notification_pipe_read_fd
);
4485 notification
= lttng_event_notifier_notification_create(token
, domain
,
4486 capture_buffer
, capture_buffer_size
);
4487 if (notification
== NULL
) {
4492 * Ownership transfered to the lttng_event_notifier_notification object.
4494 capture_buffer
= NULL
;
4497 free(capture_buffer
);
4498 return notification
;
4502 int dispatch_one_event_notifier_notification(struct notification_thread_state
*state
,
4503 struct lttng_event_notifier_notification
*notification
)
4505 struct cds_lfht_node
*node
;
4506 struct cds_lfht_iter iter
;
4507 struct notification_trigger_tokens_ht_element
*element
;
4508 enum lttng_trigger_status trigger_status
;
4509 struct lttng_evaluation
*evaluation
= NULL
;
4510 enum action_executor_status executor_status
;
4511 struct notification_client_list
*client_list
= NULL
;
4512 const char *trigger_name
;
4514 unsigned int capture_count
= 0;
4516 /* Find triggers associated with this token. */
4518 cds_lfht_lookup(state
->trigger_tokens_ht
,
4519 hash_key_u64(¬ification
->tracer_token
, lttng_ht_seed
),
4520 match_trigger_token
, ¬ification
->tracer_token
, &iter
);
4521 node
= cds_lfht_iter_get_node(&iter
);
4522 if (caa_unlikely(!node
)) {
4524 * This is not an error, slow consumption of the tracer
4525 * notifications can lead to situations where a trigger is
4526 * removed but we still get tracer notifications matching a
4527 * trigger that no longer exists.
4533 element
= caa_container_of(node
,
4534 struct notification_trigger_tokens_ht_element
,
4537 trigger_status
= lttng_trigger_get_name(element
->trigger
, &trigger_name
);
4538 assert(trigger_status
== LTTNG_TRIGGER_STATUS_OK
);
4540 if (lttng_condition_on_event_get_capture_descriptor_count(
4541 lttng_trigger_get_const_condition(element
->trigger
),
4542 &capture_count
) != LTTNG_CONDITION_STATUS_OK
) {
4543 ERR("Failed to get capture count");
4548 if (!notification
->capture_buffer
&& capture_count
!= 0) {
4549 ERR("Expected capture but capture buffer is null");
4554 evaluation
= lttng_evaluation_on_event_create(
4555 container_of(lttng_trigger_get_const_condition(
4557 struct lttng_condition_on_event
,
4559 notification
->capture_buffer
,
4560 notification
->capture_buf_size
, false);
4562 if (evaluation
== NULL
) {
4563 ERR("[notification-thread] Failed to create event rule hit evaluation while creating and enqueuing action executor job");
4567 client_list
= get_client_list_from_condition(state
,
4568 lttng_trigger_get_const_condition(element
->trigger
));
4569 executor_status
= action_executor_enqueue(state
->executor
,
4570 element
->trigger
, evaluation
, NULL
, client_list
);
4571 switch (executor_status
) {
4572 case ACTION_EXECUTOR_STATUS_OK
:
4575 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4577 struct notification_client_list_element
*client_list_element
,
4581 * Not a fatal error; this is expected and simply means the
4582 * executor has too much work queued already.
4586 /* No clients subscribed to notifications for this trigger. */
4591 /* Warn clients that a notification (or more) was dropped. */
4592 pthread_mutex_lock(&client_list
->lock
);
4593 cds_list_for_each_entry_safe(client_list_element
, tmp
,
4594 &client_list
->clients_list
, node
) {
4595 enum client_transmission_status transmission_status
;
4596 struct notification_client
*client
=
4597 client_list_element
->client
;
4599 pthread_mutex_lock(&client
->lock
);
4600 ret
= client_notification_overflow(client
);
4606 transmission_status
=
4607 client_flush_outgoing_queue(client
);
4608 ret
= client_handle_transmission_status(
4609 client
, transmission_status
, state
);
4615 pthread_mutex_unlock(&client
->lock
);
4621 pthread_mutex_unlock(&client_list
->lock
);
4624 case ACTION_EXECUTOR_STATUS_INVALID
:
4625 case ACTION_EXECUTOR_STATUS_ERROR
:
4626 /* Fatal error, shut down everything. */
4627 ERR("Fatal error encoutered while enqueuing action to the action executor");
4631 /* Unhandled error. */
4636 notification_client_list_put(client_list
);
4643 int handle_one_event_notifier_notification(
4644 struct notification_thread_state
*state
,
4645 int pipe
, enum lttng_domain_type domain
)
4648 struct lttng_event_notifier_notification
*notification
= NULL
;
4650 notification
= recv_one_event_notifier_notification(pipe
, domain
);
4651 if (notification
== NULL
) {
4652 /* Reception failed, don't consider it fatal. */
4653 ERR("[notification-thread] Error receiving an event notifier notification from tracer: fd = %i, domain = %s",
4654 pipe
, lttng_domain_type_str(domain
));
4658 ret
= dispatch_one_event_notifier_notification(state
, notification
);
4660 ERR("[notification-thread] Error dispatching an event notifier notification from tracer: fd = %i, domain = %s",
4661 pipe
, lttng_domain_type_str(domain
));
4666 lttng_event_notifier_notification_destroy(notification
);
4670 int handle_notification_thread_event_notification(struct notification_thread_state
*state
,
4671 int pipe
, enum lttng_domain_type domain
)
4673 return handle_one_event_notifier_notification(state
, pipe
, domain
);
4676 int handle_notification_thread_channel_sample(
4677 struct notification_thread_state
*state
, int pipe
,
4678 enum lttng_domain_type domain
)
4681 struct lttcomm_consumer_channel_monitor_msg sample_msg
;
4682 struct channel_info
*channel_info
;
4683 struct cds_lfht_node
*node
;
4684 struct cds_lfht_iter iter
;
4685 struct lttng_channel_trigger_list
*trigger_list
;
4686 struct lttng_trigger_list_element
*trigger_list_element
;
4687 bool previous_sample_available
= false;
4688 struct channel_state_sample previous_sample
, latest_sample
;
4689 uint64_t previous_session_consumed_total
, latest_session_consumed_total
;
4690 struct lttng_credentials channel_creds
;
4693 * The monitoring pipe only holds messages smaller than PIPE_BUF,
4694 * ensuring that read/write of sampling messages are atomic.
4696 ret
= lttng_read(pipe
, &sample_msg
, sizeof(sample_msg
));
4697 if (ret
!= sizeof(sample_msg
)) {
4698 ERR("[notification-thread] Failed to read from monitoring pipe (fd = %i)",
4705 latest_sample
.key
.key
= sample_msg
.key
;
4706 latest_sample
.key
.domain
= domain
;
4707 latest_sample
.highest_usage
= sample_msg
.highest
;
4708 latest_sample
.lowest_usage
= sample_msg
.lowest
;
4709 latest_sample
.channel_total_consumed
= sample_msg
.total_consumed
;
4713 /* Retrieve the channel's informations */
4714 cds_lfht_lookup(state
->channels_ht
,
4715 hash_channel_key(&latest_sample
.key
),
4719 node
= cds_lfht_iter_get_node(&iter
);
4720 if (caa_unlikely(!node
)) {
4722 * Not an error since the consumer can push a sample to the pipe
4723 * and the rest of the session daemon could notify us of the
4724 * channel's destruction before we get a chance to process that
4727 DBG("[notification-thread] Received a sample for an unknown channel from consumerd, key = %" PRIu64
" in %s domain",
4728 latest_sample
.key
.key
,
4729 lttng_domain_type_str(domain
));
4732 channel_info
= caa_container_of(node
, struct channel_info
,
4734 DBG("[notification-thread] Handling channel sample for channel %s (key = %" PRIu64
") in session %s (highest usage = %" PRIu64
", lowest usage = %" PRIu64
", total consumed = %" PRIu64
")",
4736 latest_sample
.key
.key
,
4737 channel_info
->session_info
->name
,
4738 latest_sample
.highest_usage
,
4739 latest_sample
.lowest_usage
,
4740 latest_sample
.channel_total_consumed
);
4742 previous_session_consumed_total
=
4743 channel_info
->session_info
->consumed_data_size
;
4745 /* Retrieve the channel's last sample, if it exists, and update it. */
4746 cds_lfht_lookup(state
->channel_state_ht
,
4747 hash_channel_key(&latest_sample
.key
),
4748 match_channel_state_sample
,
4751 node
= cds_lfht_iter_get_node(&iter
);
4752 if (caa_likely(node
)) {
4753 struct channel_state_sample
*stored_sample
;
4755 /* Update the sample stored. */
4756 stored_sample
= caa_container_of(node
,
4757 struct channel_state_sample
,
4758 channel_state_ht_node
);
4760 memcpy(&previous_sample
, stored_sample
,
4761 sizeof(previous_sample
));
4762 stored_sample
->highest_usage
= latest_sample
.highest_usage
;
4763 stored_sample
->lowest_usage
= latest_sample
.lowest_usage
;
4764 stored_sample
->channel_total_consumed
= latest_sample
.channel_total_consumed
;
4765 previous_sample_available
= true;
4767 latest_session_consumed_total
=
4768 previous_session_consumed_total
+
4769 (latest_sample
.channel_total_consumed
- previous_sample
.channel_total_consumed
);
4772 * This is the channel's first sample, allocate space for and
4773 * store the new sample.
4775 struct channel_state_sample
*stored_sample
;
4777 stored_sample
= zmalloc(sizeof(*stored_sample
));
4778 if (!stored_sample
) {
4783 memcpy(stored_sample
, &latest_sample
, sizeof(*stored_sample
));
4784 cds_lfht_node_init(&stored_sample
->channel_state_ht_node
);
4785 cds_lfht_add(state
->channel_state_ht
,
4786 hash_channel_key(&stored_sample
->key
),
4787 &stored_sample
->channel_state_ht_node
);
4789 latest_session_consumed_total
=
4790 previous_session_consumed_total
+
4791 latest_sample
.channel_total_consumed
;
4794 channel_info
->session_info
->consumed_data_size
=
4795 latest_session_consumed_total
;
4797 /* Find triggers associated with this channel. */
4798 cds_lfht_lookup(state
->channel_triggers_ht
,
4799 hash_channel_key(&latest_sample
.key
),
4800 match_channel_trigger_list
,
4803 node
= cds_lfht_iter_get_node(&iter
);
4804 if (caa_likely(!node
)) {
4808 channel_creds
= (typeof(channel_creds
)) {
4809 .uid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->uid
),
4810 .gid
= LTTNG_OPTIONAL_INIT_VALUE(channel_info
->session_info
->gid
),
4813 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
4814 channel_triggers_ht_node
);
4815 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
4817 const struct lttng_condition
*condition
;
4818 struct lttng_trigger
*trigger
;
4819 struct notification_client_list
*client_list
= NULL
;
4820 struct lttng_evaluation
*evaluation
= NULL
;
4821 enum action_executor_status executor_status
;
4824 trigger
= trigger_list_element
->trigger
;
4825 condition
= lttng_trigger_get_const_condition(trigger
);
4829 * Check if any client is subscribed to the result of this
4832 client_list
= get_client_list_from_condition(state
, condition
);
4834 ret
= evaluate_buffer_condition(condition
, &evaluation
, state
,
4835 previous_sample_available
? &previous_sample
: NULL
,
4837 previous_session_consumed_total
,
4838 latest_session_consumed_total
,
4840 if (caa_unlikely(ret
)) {
4844 if (caa_likely(!evaluation
)) {
4849 * Ownership of `evaluation` transferred to the action executor
4850 * no matter the result.
4852 executor_status
= action_executor_enqueue(state
->executor
,
4853 trigger
, evaluation
, &channel_creds
,
4856 switch (executor_status
) {
4857 case ACTION_EXECUTOR_STATUS_OK
:
4859 case ACTION_EXECUTOR_STATUS_ERROR
:
4860 case ACTION_EXECUTOR_STATUS_INVALID
:
4862 * TODO Add trigger identification (name/id) when
4863 * it is added to the API.
4865 ERR("Fatal error occurred while enqueuing action associated with buffer-condition trigger");
4868 case ACTION_EXECUTOR_STATUS_OVERFLOW
:
4870 * TODO Add trigger identification (name/id) when
4871 * it is added to the API.
4873 * Not a fatal error.
4875 WARN("No space left when enqueuing action associated with buffer-condition trigger");
4883 notification_client_list_put(client_list
);
4884 if (caa_unlikely(ret
)) {