2 * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License, version 2 only, as
6 * published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc., 51
15 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
20 #include <urcu/rculfhash.h>
22 #include <common/defaults.h>
23 #include <common/error.h>
24 #include <common/futex.h>
25 #include <common/unix.h>
26 #include <common/dynamic-buffer.h>
27 #include <common/hashtable/utils.h>
28 #include <common/sessiond-comm/sessiond-comm.h>
29 #include <common/macros.h>
30 #include <lttng/condition/condition.h>
31 #include <lttng/action/action-internal.h>
32 #include <lttng/notification/notification-internal.h>
33 #include <lttng/condition/condition-internal.h>
34 #include <lttng/condition/buffer-usage-internal.h>
35 #include <lttng/condition/session-consumed-size-internal.h>
36 #include <lttng/condition/session-rotation-internal.h>
37 #include <lttng/notification/channel-internal.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 enum lttng_object_type
{
55 LTTNG_OBJECT_TYPE_UNKNOWN
,
56 LTTNG_OBJECT_TYPE_NONE
,
57 LTTNG_OBJECT_TYPE_CHANNEL
,
58 LTTNG_OBJECT_TYPE_SESSION
,
61 struct lttng_trigger_list_element
{
62 /* No ownership of the trigger object is assumed. */
63 const struct lttng_trigger
*trigger
;
64 struct cds_list_head node
;
67 struct lttng_channel_trigger_list
{
68 struct channel_key channel_key
;
69 /* List of struct lttng_trigger_list_element. */
70 struct cds_list_head list
;
71 /* Node in the channel_triggers_ht */
72 struct cds_lfht_node channel_triggers_ht_node
;
73 /* call_rcu delayed reclaim. */
74 struct rcu_head rcu_node
;
78 * List of triggers applying to a given session.
81 * - lttng_session_trigger_list_create()
82 * - lttng_session_trigger_list_build()
83 * - lttng_session_trigger_list_destroy()
84 * - lttng_session_trigger_list_add()
86 struct lttng_session_trigger_list
{
88 * Not owned by this; points to the session_info structure's
91 const char *session_name
;
92 /* List of struct lttng_trigger_list_element. */
93 struct cds_list_head list
;
94 /* Node in the session_triggers_ht */
95 struct cds_lfht_node session_triggers_ht_node
;
97 * Weak reference to the notification system's session triggers
100 * The session trigger list structure structure is owned by
101 * the session's session_info.
103 * The session_info is kept alive the the channel_infos holding a
104 * reference to it (reference counting). When those channels are
105 * destroyed (at runtime or on teardown), the reference they hold
106 * to the session_info are released. On destruction of session_info,
107 * session_info_destroy() will remove the list of triggers applying
108 * to this session from the notification system's state.
110 * This implies that the session_triggers_ht must be destroyed
111 * after the channels.
113 struct cds_lfht
*session_triggers_ht
;
114 /* Used for delayed RCU reclaim. */
115 struct rcu_head rcu_node
;
118 struct lttng_trigger_ht_element
{
119 struct lttng_trigger
*trigger
;
120 struct cds_lfht_node node
;
121 /* call_rcu delayed reclaim. */
122 struct rcu_head rcu_node
;
125 struct lttng_condition_list_element
{
126 struct lttng_condition
*condition
;
127 struct cds_list_head node
;
130 struct notification_client_list_element
{
131 struct notification_client
*client
;
132 struct cds_list_head node
;
135 struct notification_client_list
{
136 const struct lttng_trigger
*trigger
;
137 struct cds_list_head list
;
138 struct cds_lfht_node notification_trigger_ht_node
;
139 /* call_rcu delayed reclaim. */
140 struct rcu_head rcu_node
;
143 struct notification_client
{
145 /* Client protocol version. */
146 uint8_t major
, minor
;
150 * Indicates if the credentials and versions of the client have been
155 * Conditions to which the client's notification channel is subscribed.
156 * List of struct lttng_condition_list_node. The condition member is
157 * owned by the client.
159 struct cds_list_head condition_list
;
160 struct cds_lfht_node client_socket_ht_node
;
164 * During the reception of a message, the reception
165 * buffers' "size" is set to contain the current
166 * message's complete payload.
168 struct lttng_dynamic_buffer buffer
;
169 /* Bytes left to receive for the current message. */
170 size_t bytes_to_receive
;
171 /* Type of the message being received. */
172 enum lttng_notification_channel_message_type msg_type
;
174 * Indicates whether or not credentials are expected
179 * Indicates whether or not credentials were received
183 /* Only used during credentials reception. */
184 lttng_sock_cred creds
;
188 * Indicates whether or not a notification addressed to
189 * this client was dropped because a command reply was
192 * A notification is dropped whenever the buffer is not
195 bool dropped_notification
;
197 * Indicates whether or not a command reply is already
198 * buffered. In this case, it means that the client is
199 * not consuming command replies before emitting a new
200 * one. This could be caused by a protocol error or a
201 * misbehaving/malicious client.
203 bool queued_command_reply
;
204 struct lttng_dynamic_buffer buffer
;
207 /* call_rcu delayed reclaim. */
208 struct rcu_head rcu_node
;
211 struct channel_state_sample
{
212 struct channel_key key
;
213 struct cds_lfht_node channel_state_ht_node
;
214 uint64_t highest_usage
;
215 uint64_t lowest_usage
;
216 uint64_t channel_total_consumed
;
217 /* call_rcu delayed reclaim. */
218 struct rcu_head rcu_node
;
221 static unsigned long hash_channel_key(struct channel_key
*key
);
222 static int evaluate_buffer_condition(const struct lttng_condition
*condition
,
223 struct lttng_evaluation
**evaluation
,
224 const struct notification_thread_state
*state
,
225 const struct channel_state_sample
*previous_sample
,
226 const struct channel_state_sample
*latest_sample
,
227 uint64_t previous_session_consumed_total
,
228 uint64_t latest_session_consumed_total
,
229 struct channel_info
*channel_info
);
231 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
232 const struct lttng_evaluation
*evaluation
,
233 struct notification_client_list
*client_list
,
234 struct notification_thread_state
*state
,
235 uid_t channel_uid
, gid_t channel_gid
);
238 /* session_info API */
240 void session_info_destroy(void *_data
);
242 void session_info_get(struct session_info
*session_info
);
244 void session_info_put(struct session_info
*session_info
);
246 struct session_info
*session_info_create(const char *name
,
247 uid_t uid
, gid_t gid
,
248 struct lttng_session_trigger_list
*trigger_list
,
249 struct cds_lfht
*sessions_ht
);
251 void session_info_add_channel(struct session_info
*session_info
,
252 struct channel_info
*channel_info
);
254 void session_info_remove_channel(struct session_info
*session_info
,
255 struct channel_info
*channel_info
);
257 /* lttng_session_trigger_list API */
259 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
260 const char *session_name
,
261 struct cds_lfht
*session_triggers_ht
);
263 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
264 const struct notification_thread_state
*state
,
265 const char *session_name
);
267 void lttng_session_trigger_list_destroy(
268 struct lttng_session_trigger_list
*list
);
270 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
271 const struct lttng_trigger
*trigger
);
275 int match_client(struct cds_lfht_node
*node
, const void *key
)
277 /* This double-cast is intended to supress pointer-to-cast warning. */
278 int socket
= (int) (intptr_t) key
;
279 struct notification_client
*client
;
281 client
= caa_container_of(node
, struct notification_client
,
282 client_socket_ht_node
);
284 return !!(client
->socket
== socket
);
288 int match_channel_trigger_list(struct cds_lfht_node
*node
, const void *key
)
290 struct channel_key
*channel_key
= (struct channel_key
*) key
;
291 struct lttng_channel_trigger_list
*trigger_list
;
293 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
294 channel_triggers_ht_node
);
296 return !!((channel_key
->key
== trigger_list
->channel_key
.key
) &&
297 (channel_key
->domain
== trigger_list
->channel_key
.domain
));
301 int match_session_trigger_list(struct cds_lfht_node
*node
, const void *key
)
303 const char *session_name
= (const char *) key
;
304 struct lttng_session_trigger_list
*trigger_list
;
306 trigger_list
= caa_container_of(node
, struct lttng_session_trigger_list
,
307 session_triggers_ht_node
);
309 return !!(strcmp(trigger_list
->session_name
, session_name
) == 0);
313 int match_channel_state_sample(struct cds_lfht_node
*node
, const void *key
)
315 struct channel_key
*channel_key
= (struct channel_key
*) key
;
316 struct channel_state_sample
*sample
;
318 sample
= caa_container_of(node
, struct channel_state_sample
,
319 channel_state_ht_node
);
321 return !!((channel_key
->key
== sample
->key
.key
) &&
322 (channel_key
->domain
== sample
->key
.domain
));
326 int match_channel_info(struct cds_lfht_node
*node
, const void *key
)
328 struct channel_key
*channel_key
= (struct channel_key
*) key
;
329 struct channel_info
*channel_info
;
331 channel_info
= caa_container_of(node
, struct channel_info
,
334 return !!((channel_key
->key
== channel_info
->key
.key
) &&
335 (channel_key
->domain
== channel_info
->key
.domain
));
339 int match_condition(struct cds_lfht_node
*node
, const void *key
)
341 struct lttng_condition
*condition_key
= (struct lttng_condition
*) key
;
342 struct lttng_trigger_ht_element
*trigger
;
343 struct lttng_condition
*condition
;
345 trigger
= caa_container_of(node
, struct lttng_trigger_ht_element
,
347 condition
= lttng_trigger_get_condition(trigger
->trigger
);
350 return !!lttng_condition_is_equal(condition_key
, condition
);
354 int match_client_list_condition(struct cds_lfht_node
*node
, const void *key
)
356 struct lttng_condition
*condition_key
= (struct lttng_condition
*) key
;
357 struct notification_client_list
*client_list
;
358 const struct lttng_condition
*condition
;
360 assert(condition_key
);
362 client_list
= caa_container_of(node
, struct notification_client_list
,
363 notification_trigger_ht_node
);
364 condition
= lttng_trigger_get_const_condition(client_list
->trigger
);
366 return !!lttng_condition_is_equal(condition_key
, condition
);
370 int match_session(struct cds_lfht_node
*node
, const void *key
)
372 const char *name
= key
;
373 struct session_info
*session_info
= caa_container_of(
374 node
, struct session_info
, sessions_ht_node
);
376 return !strcmp(session_info
->name
, name
);
380 unsigned long lttng_condition_buffer_usage_hash(
381 const struct lttng_condition
*_condition
)
384 unsigned long condition_type
;
385 struct lttng_condition_buffer_usage
*condition
;
387 condition
= container_of(_condition
,
388 struct lttng_condition_buffer_usage
, parent
);
390 condition_type
= (unsigned long) condition
->parent
.type
;
391 hash
= hash_key_ulong((void *) condition_type
, lttng_ht_seed
);
392 if (condition
->session_name
) {
393 hash
^= hash_key_str(condition
->session_name
, lttng_ht_seed
);
395 if (condition
->channel_name
) {
396 hash
^= hash_key_str(condition
->channel_name
, lttng_ht_seed
);
398 if (condition
->domain
.set
) {
399 hash
^= hash_key_ulong(
400 (void *) condition
->domain
.type
,
403 if (condition
->threshold_ratio
.set
) {
406 val
= condition
->threshold_ratio
.value
* (double) UINT32_MAX
;
407 hash
^= hash_key_u64(&val
, lttng_ht_seed
);
408 } else if (condition
->threshold_bytes
.set
) {
411 val
= condition
->threshold_bytes
.value
;
412 hash
^= hash_key_u64(&val
, lttng_ht_seed
);
418 unsigned long lttng_condition_session_consumed_size_hash(
419 const struct lttng_condition
*_condition
)
422 unsigned long condition_type
=
423 (unsigned long) LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
;
424 struct lttng_condition_session_consumed_size
*condition
;
427 condition
= container_of(_condition
,
428 struct lttng_condition_session_consumed_size
, parent
);
430 hash
= hash_key_ulong((void *) condition_type
, lttng_ht_seed
);
431 if (condition
->session_name
) {
432 hash
^= hash_key_str(condition
->session_name
, lttng_ht_seed
);
434 val
= condition
->consumed_threshold_bytes
.value
;
435 hash
^= hash_key_u64(&val
, lttng_ht_seed
);
440 unsigned long lttng_condition_session_rotation_hash(
441 const struct lttng_condition
*_condition
)
443 unsigned long hash
, condition_type
;
444 struct lttng_condition_session_rotation
*condition
;
446 condition
= container_of(_condition
,
447 struct lttng_condition_session_rotation
, parent
);
448 condition_type
= (unsigned long) condition
->parent
.type
;
449 hash
= hash_key_ulong((void *) condition_type
, lttng_ht_seed
);
450 assert(condition
->session_name
);
451 hash
^= hash_key_str(condition
->session_name
, lttng_ht_seed
);
456 * The lttng_condition hashing code is kept in this file (rather than
457 * condition.c) since it makes use of GPLv2 code (hashtable utils), which we
458 * don't want to link in liblttng-ctl.
461 unsigned long lttng_condition_hash(const struct lttng_condition
*condition
)
463 switch (condition
->type
) {
464 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
465 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
466 return lttng_condition_buffer_usage_hash(condition
);
467 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
468 return lttng_condition_session_consumed_size_hash(condition
);
469 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
470 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
471 return lttng_condition_session_rotation_hash(condition
);
473 ERR("[notification-thread] Unexpected condition type caught");
479 unsigned long hash_channel_key(struct channel_key
*key
)
481 unsigned long key_hash
= hash_key_u64(&key
->key
, lttng_ht_seed
);
482 unsigned long domain_hash
= hash_key_ulong(
483 (void *) (unsigned long) key
->domain
, lttng_ht_seed
);
485 return key_hash
^ domain_hash
;
489 * Get the type of object to which a given condition applies. Bindings let
490 * the notification system evaluate a trigger's condition when a given
491 * object's state is updated.
493 * For instance, a condition bound to a channel will be evaluated everytime
494 * the channel's state is changed by a channel monitoring sample.
497 enum lttng_object_type
get_condition_binding_object(
498 const struct lttng_condition
*condition
)
500 switch (lttng_condition_get_type(condition
)) {
501 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
502 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
503 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
504 return LTTNG_OBJECT_TYPE_CHANNEL
;
505 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
506 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
507 return LTTNG_OBJECT_TYPE_SESSION
;
509 return LTTNG_OBJECT_TYPE_UNKNOWN
;
514 void free_channel_info_rcu(struct rcu_head
*node
)
516 free(caa_container_of(node
, struct channel_info
, rcu_node
));
520 void channel_info_destroy(struct channel_info
*channel_info
)
526 if (channel_info
->session_info
) {
527 session_info_remove_channel(channel_info
->session_info
,
529 session_info_put(channel_info
->session_info
);
531 if (channel_info
->name
) {
532 free(channel_info
->name
);
534 call_rcu(&channel_info
->rcu_node
, free_channel_info_rcu
);
538 void free_session_info_rcu(struct rcu_head
*node
)
540 free(caa_container_of(node
, struct session_info
, rcu_node
));
543 /* Don't call directly, use the ref-counting mechanism. */
545 void session_info_destroy(void *_data
)
547 struct session_info
*session_info
= _data
;
550 assert(session_info
);
551 if (session_info
->channel_infos_ht
) {
552 ret
= cds_lfht_destroy(session_info
->channel_infos_ht
, NULL
);
554 ERR("[notification-thread] Failed to destroy channel information hash table");
557 lttng_session_trigger_list_destroy(session_info
->trigger_list
);
560 cds_lfht_del(session_info
->sessions_ht
,
561 &session_info
->sessions_ht_node
);
563 free(session_info
->name
);
564 call_rcu(&session_info
->rcu_node
, free_session_info_rcu
);
568 void session_info_get(struct session_info
*session_info
)
573 lttng_ref_get(&session_info
->ref
);
577 void session_info_put(struct session_info
*session_info
)
582 lttng_ref_put(&session_info
->ref
);
586 struct session_info
*session_info_create(const char *name
, uid_t uid
, gid_t gid
,
587 struct lttng_session_trigger_list
*trigger_list
,
588 struct cds_lfht
*sessions_ht
)
590 struct session_info
*session_info
;
594 session_info
= zmalloc(sizeof(*session_info
));
598 lttng_ref_init(&session_info
->ref
, session_info_destroy
);
600 session_info
->channel_infos_ht
= cds_lfht_new(DEFAULT_HT_SIZE
,
601 1, 0, CDS_LFHT_AUTO_RESIZE
| CDS_LFHT_ACCOUNTING
, NULL
);
602 if (!session_info
->channel_infos_ht
) {
606 cds_lfht_node_init(&session_info
->sessions_ht_node
);
607 session_info
->name
= strdup(name
);
608 if (!session_info
->name
) {
611 session_info
->uid
= uid
;
612 session_info
->gid
= gid
;
613 session_info
->trigger_list
= trigger_list
;
614 session_info
->sessions_ht
= sessions_ht
;
618 session_info_put(session_info
);
623 void session_info_add_channel(struct session_info
*session_info
,
624 struct channel_info
*channel_info
)
627 cds_lfht_add(session_info
->channel_infos_ht
,
628 hash_channel_key(&channel_info
->key
),
629 &channel_info
->session_info_channels_ht_node
);
634 void session_info_remove_channel(struct session_info
*session_info
,
635 struct channel_info
*channel_info
)
638 cds_lfht_del(session_info
->channel_infos_ht
,
639 &channel_info
->session_info_channels_ht_node
);
644 struct channel_info
*channel_info_create(const char *channel_name
,
645 struct channel_key
*channel_key
, uint64_t channel_capacity
,
646 struct session_info
*session_info
)
648 struct channel_info
*channel_info
= zmalloc(sizeof(*channel_info
));
654 cds_lfht_node_init(&channel_info
->channels_ht_node
);
655 cds_lfht_node_init(&channel_info
->session_info_channels_ht_node
);
656 memcpy(&channel_info
->key
, channel_key
, sizeof(*channel_key
));
657 channel_info
->capacity
= channel_capacity
;
659 channel_info
->name
= strdup(channel_name
);
660 if (!channel_info
->name
) {
665 * Set the references between session and channel infos:
666 * - channel_info holds a strong reference to session_info
667 * - session_info holds a weak reference to channel_info
669 session_info_get(session_info
);
670 session_info_add_channel(session_info
, channel_info
);
671 channel_info
->session_info
= session_info
;
675 channel_info_destroy(channel_info
);
679 /* RCU read lock must be held by the caller. */
681 struct notification_client_list
*get_client_list_from_condition(
682 struct notification_thread_state
*state
,
683 const struct lttng_condition
*condition
)
685 struct cds_lfht_node
*node
;
686 struct cds_lfht_iter iter
;
688 cds_lfht_lookup(state
->notification_trigger_clients_ht
,
689 lttng_condition_hash(condition
),
690 match_client_list_condition
,
693 node
= cds_lfht_iter_get_node(&iter
);
695 return node
? caa_container_of(node
,
696 struct notification_client_list
,
697 notification_trigger_ht_node
) : NULL
;
700 /* This function must be called with the RCU read lock held. */
702 int evaluate_channel_condition_for_client(
703 const struct lttng_condition
*condition
,
704 struct notification_thread_state
*state
,
705 struct lttng_evaluation
**evaluation
,
706 uid_t
*session_uid
, gid_t
*session_gid
)
709 struct cds_lfht_iter iter
;
710 struct cds_lfht_node
*node
;
711 struct channel_info
*channel_info
= NULL
;
712 struct channel_key
*channel_key
= NULL
;
713 struct channel_state_sample
*last_sample
= NULL
;
714 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
716 /* Find the channel associated with the condition. */
717 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
,
718 channel_trigger_list
, channel_triggers_ht_node
) {
719 struct lttng_trigger_list_element
*element
;
721 cds_list_for_each_entry(element
, &channel_trigger_list
->list
, node
) {
722 const struct lttng_condition
*current_condition
=
723 lttng_trigger_get_const_condition(
726 assert(current_condition
);
727 if (!lttng_condition_is_equal(condition
,
728 current_condition
)) {
732 /* Found the trigger, save the channel key. */
733 channel_key
= &channel_trigger_list
->channel_key
;
737 /* The channel key was found stop iteration. */
743 /* No channel found; normal exit. */
744 DBG("[notification-thread] No known channel associated with newly subscribed-to condition");
749 /* Fetch channel info for the matching channel. */
750 cds_lfht_lookup(state
->channels_ht
,
751 hash_channel_key(channel_key
),
755 node
= cds_lfht_iter_get_node(&iter
);
757 channel_info
= caa_container_of(node
, struct channel_info
,
760 /* Retrieve the channel's last sample, if it exists. */
761 cds_lfht_lookup(state
->channel_state_ht
,
762 hash_channel_key(channel_key
),
763 match_channel_state_sample
,
766 node
= cds_lfht_iter_get_node(&iter
);
768 last_sample
= caa_container_of(node
,
769 struct channel_state_sample
,
770 channel_state_ht_node
);
772 /* Nothing to evaluate, no sample was ever taken. Normal exit */
773 DBG("[notification-thread] No channel sample associated with newly subscribed-to condition");
778 ret
= evaluate_buffer_condition(condition
, evaluation
, state
,
780 0, channel_info
->session_info
->consumed_data_size
,
783 WARN("[notification-thread] Fatal error occurred while evaluating a newly subscribed-to condition");
787 *session_uid
= channel_info
->session_info
->uid
;
788 *session_gid
= channel_info
->session_info
->gid
;
794 const char *get_condition_session_name(const struct lttng_condition
*condition
)
796 const char *session_name
= NULL
;
797 enum lttng_condition_status status
;
799 switch (lttng_condition_get_type(condition
)) {
800 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
801 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
802 status
= lttng_condition_buffer_usage_get_session_name(
803 condition
, &session_name
);
805 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
806 status
= lttng_condition_session_consumed_size_get_session_name(
807 condition
, &session_name
);
809 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
810 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
811 status
= lttng_condition_session_rotation_get_session_name(
812 condition
, &session_name
);
817 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
818 ERR("[notification-thread] Failed to retrieve session rotation condition's session name");
825 /* This function must be called with the RCU read lock held. */
827 int evaluate_session_condition_for_client(
828 const struct lttng_condition
*condition
,
829 struct notification_thread_state
*state
,
830 struct lttng_evaluation
**evaluation
,
831 uid_t
*session_uid
, gid_t
*session_gid
)
834 struct cds_lfht_iter iter
;
835 struct cds_lfht_node
*node
;
836 const char *session_name
;
837 struct session_info
*session_info
= NULL
;
839 session_name
= get_condition_session_name(condition
);
841 /* Find the session associated with the trigger. */
842 cds_lfht_lookup(state
->sessions_ht
,
843 hash_key_str(session_name
, lttng_ht_seed
),
847 node
= cds_lfht_iter_get_node(&iter
);
849 DBG("[notification-thread] No known session matching name \"%s\"",
855 session_info
= caa_container_of(node
, struct session_info
,
857 session_info_get(session_info
);
860 * Evaluation is performed in-line here since only one type of
861 * session-bound condition is handled for the moment.
863 switch (lttng_condition_get_type(condition
)) {
864 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
865 if (!session_info
->rotation
.ongoing
) {
867 goto end_session_put
;
870 *evaluation
= lttng_evaluation_session_rotation_ongoing_create(
871 session_info
->rotation
.id
);
874 ERR("[notification-thread] Failed to create session rotation ongoing evaluation for session \"%s\"",
877 goto end_session_put
;
883 goto end_session_put
;
886 *session_uid
= session_info
->uid
;
887 *session_gid
= session_info
->gid
;
890 session_info_put(session_info
);
895 /* This function must be called with the RCU read lock held. */
897 int evaluate_condition_for_client(const struct lttng_trigger
*trigger
,
898 const struct lttng_condition
*condition
,
899 struct notification_client
*client
,
900 struct notification_thread_state
*state
)
903 struct lttng_evaluation
*evaluation
= NULL
;
904 struct notification_client_list client_list
= { 0 };
905 struct notification_client_list_element client_list_element
= { 0 };
906 uid_t object_uid
= 0;
907 gid_t object_gid
= 0;
914 switch (get_condition_binding_object(condition
)) {
915 case LTTNG_OBJECT_TYPE_SESSION
:
916 ret
= evaluate_session_condition_for_client(condition
, state
,
917 &evaluation
, &object_uid
, &object_gid
);
919 case LTTNG_OBJECT_TYPE_CHANNEL
:
920 ret
= evaluate_channel_condition_for_client(condition
, state
,
921 &evaluation
, &object_uid
, &object_gid
);
923 case LTTNG_OBJECT_TYPE_NONE
:
926 case LTTNG_OBJECT_TYPE_UNKNOWN
:
933 /* Evaluation yielded nothing. Normal exit. */
934 DBG("[notification-thread] Newly subscribed-to condition evaluated to false, nothing to report to client");
940 * Create a temporary client list with the client currently
943 cds_lfht_node_init(&client_list
.notification_trigger_ht_node
);
944 CDS_INIT_LIST_HEAD(&client_list
.list
);
945 client_list
.trigger
= trigger
;
947 CDS_INIT_LIST_HEAD(&client_list_element
.node
);
948 client_list_element
.client
= client
;
949 cds_list_add(&client_list_element
.node
, &client_list
.list
);
951 /* Send evaluation result to the newly-subscribed client. */
952 DBG("[notification-thread] Newly subscribed-to condition evaluated to true, notifying client");
953 ret
= send_evaluation_to_clients(trigger
, evaluation
, &client_list
,
954 state
, object_uid
, object_gid
);
961 int notification_thread_client_subscribe(struct notification_client
*client
,
962 struct lttng_condition
*condition
,
963 struct notification_thread_state
*state
,
964 enum lttng_notification_channel_status
*_status
)
967 struct notification_client_list
*client_list
;
968 struct lttng_condition_list_element
*condition_list_element
= NULL
;
969 struct notification_client_list_element
*client_list_element
= NULL
;
970 enum lttng_notification_channel_status status
=
971 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
974 * Ensure that the client has not already subscribed to this condition
977 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
, node
) {
978 if (lttng_condition_is_equal(condition_list_element
->condition
,
980 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_ALREADY_SUBSCRIBED
;
985 condition_list_element
= zmalloc(sizeof(*condition_list_element
));
986 if (!condition_list_element
) {
990 client_list_element
= zmalloc(sizeof(*client_list_element
));
991 if (!client_list_element
) {
999 * Add the newly-subscribed condition to the client's subscription list.
1001 CDS_INIT_LIST_HEAD(&condition_list_element
->node
);
1002 condition_list_element
->condition
= condition
;
1003 cds_list_add(&condition_list_element
->node
, &client
->condition_list
);
1005 client_list
= get_client_list_from_condition(state
, condition
);
1008 * No notification-emiting trigger registered with this
1009 * condition. We don't evaluate the condition right away
1010 * since this trigger is not registered yet.
1012 free(client_list_element
);
1017 * The condition to which the client just subscribed is evaluated
1018 * at this point so that conditions that are already TRUE result
1019 * in a notification being sent out.
1021 if (evaluate_condition_for_client(client_list
->trigger
, condition
,
1023 WARN("[notification-thread] Evaluation of a condition on client subscription failed, aborting.");
1025 free(client_list_element
);
1030 * Add the client to the list of clients interested in a given trigger
1031 * if a "notification" trigger with a corresponding condition was
1034 client_list_element
->client
= client
;
1035 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
1036 cds_list_add(&client_list_element
->node
, &client_list
->list
);
1045 free(condition_list_element
);
1046 free(client_list_element
);
1051 int notification_thread_client_unsubscribe(
1052 struct notification_client
*client
,
1053 struct lttng_condition
*condition
,
1054 struct notification_thread_state
*state
,
1055 enum lttng_notification_channel_status
*_status
)
1057 struct notification_client_list
*client_list
;
1058 struct lttng_condition_list_element
*condition_list_element
,
1060 struct notification_client_list_element
*client_list_element
,
1062 bool condition_found
= false;
1063 enum lttng_notification_channel_status status
=
1064 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
1066 /* Remove the condition from the client's condition list. */
1067 cds_list_for_each_entry_safe(condition_list_element
, condition_tmp
,
1068 &client
->condition_list
, node
) {
1069 if (!lttng_condition_is_equal(condition_list_element
->condition
,
1074 cds_list_del(&condition_list_element
->node
);
1076 * The caller may be iterating on the client's conditions to
1077 * tear down a client's connection. In this case, the condition
1078 * will be destroyed at the end.
1080 if (condition
!= condition_list_element
->condition
) {
1081 lttng_condition_destroy(
1082 condition_list_element
->condition
);
1084 free(condition_list_element
);
1085 condition_found
= true;
1089 if (!condition_found
) {
1090 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNKNOWN_CONDITION
;
1095 * Remove the client from the list of clients interested the trigger
1096 * matching the condition.
1099 client_list
= get_client_list_from_condition(state
, condition
);
1104 cds_list_for_each_entry_safe(client_list_element
, client_tmp
,
1105 &client_list
->list
, node
) {
1106 if (client_list_element
->client
->socket
!= client
->socket
) {
1109 cds_list_del(&client_list_element
->node
);
1110 free(client_list_element
);
1116 lttng_condition_destroy(condition
);
1124 void free_notification_client_rcu(struct rcu_head
*node
)
1126 free(caa_container_of(node
, struct notification_client
, rcu_node
));
1130 void notification_client_destroy(struct notification_client
*client
,
1131 struct notification_thread_state
*state
)
1133 struct lttng_condition_list_element
*condition_list_element
, *tmp
;
1139 /* Release all conditions to which the client was subscribed. */
1140 cds_list_for_each_entry_safe(condition_list_element
, tmp
,
1141 &client
->condition_list
, node
) {
1142 (void) notification_thread_client_unsubscribe(client
,
1143 condition_list_element
->condition
, state
, NULL
);
1146 if (client
->socket
>= 0) {
1147 (void) lttcomm_close_unix_sock(client
->socket
);
1149 lttng_dynamic_buffer_reset(&client
->communication
.inbound
.buffer
);
1150 lttng_dynamic_buffer_reset(&client
->communication
.outbound
.buffer
);
1151 call_rcu(&client
->rcu_node
, free_notification_client_rcu
);
1155 * Call with rcu_read_lock held (and hold for the lifetime of the returned
1159 struct notification_client
*get_client_from_socket(int socket
,
1160 struct notification_thread_state
*state
)
1162 struct cds_lfht_iter iter
;
1163 struct cds_lfht_node
*node
;
1164 struct notification_client
*client
= NULL
;
1166 cds_lfht_lookup(state
->client_socket_ht
,
1167 hash_key_ulong((void *) (unsigned long) socket
, lttng_ht_seed
),
1169 (void *) (unsigned long) socket
,
1171 node
= cds_lfht_iter_get_node(&iter
);
1176 client
= caa_container_of(node
, struct notification_client
,
1177 client_socket_ht_node
);
1183 bool buffer_usage_condition_applies_to_channel(
1184 const struct lttng_condition
*condition
,
1185 const struct channel_info
*channel_info
)
1187 enum lttng_condition_status status
;
1188 enum lttng_domain_type condition_domain
;
1189 const char *condition_session_name
= NULL
;
1190 const char *condition_channel_name
= NULL
;
1192 status
= lttng_condition_buffer_usage_get_domain_type(condition
,
1194 assert(status
== LTTNG_CONDITION_STATUS_OK
);
1195 if (channel_info
->key
.domain
!= condition_domain
) {
1199 status
= lttng_condition_buffer_usage_get_session_name(
1200 condition
, &condition_session_name
);
1201 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1203 status
= lttng_condition_buffer_usage_get_channel_name(
1204 condition
, &condition_channel_name
);
1205 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_channel_name
);
1207 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1210 if (strcmp(channel_info
->name
, condition_channel_name
)) {
1220 bool session_consumed_size_condition_applies_to_channel(
1221 const struct lttng_condition
*condition
,
1222 const struct channel_info
*channel_info
)
1224 enum lttng_condition_status status
;
1225 const char *condition_session_name
= NULL
;
1227 status
= lttng_condition_session_consumed_size_get_session_name(
1228 condition
, &condition_session_name
);
1229 assert((status
== LTTNG_CONDITION_STATUS_OK
) && condition_session_name
);
1231 if (strcmp(channel_info
->session_info
->name
, condition_session_name
)) {
1241 bool trigger_applies_to_channel(const struct lttng_trigger
*trigger
,
1242 const struct channel_info
*channel_info
)
1244 const struct lttng_condition
*condition
;
1245 bool trigger_applies
;
1247 condition
= lttng_trigger_get_const_condition(trigger
);
1252 switch (lttng_condition_get_type(condition
)) {
1253 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
1254 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
1255 trigger_applies
= buffer_usage_condition_applies_to_channel(
1256 condition
, channel_info
);
1258 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
1259 trigger_applies
= session_consumed_size_condition_applies_to_channel(
1260 condition
, channel_info
);
1266 return trigger_applies
;
1272 bool trigger_applies_to_client(struct lttng_trigger
*trigger
,
1273 struct notification_client
*client
)
1275 bool applies
= false;
1276 struct lttng_condition_list_element
*condition_list_element
;
1278 cds_list_for_each_entry(condition_list_element
, &client
->condition_list
,
1280 applies
= lttng_condition_is_equal(
1281 condition_list_element
->condition
,
1282 lttng_trigger_get_condition(trigger
));
1290 /* Must be called with RCU read lock held. */
1292 struct lttng_session_trigger_list
*get_session_trigger_list(
1293 struct notification_thread_state
*state
,
1294 const char *session_name
)
1296 struct lttng_session_trigger_list
*list
= NULL
;
1297 struct cds_lfht_node
*node
;
1298 struct cds_lfht_iter iter
;
1300 cds_lfht_lookup(state
->session_triggers_ht
,
1301 hash_key_str(session_name
, lttng_ht_seed
),
1302 match_session_trigger_list
,
1305 node
= cds_lfht_iter_get_node(&iter
);
1308 * Not an error, the list of triggers applying to that session
1309 * will be initialized when the session is created.
1311 DBG("[notification-thread] No trigger list found for session \"%s\" as it is not yet known to the notification system",
1316 list
= caa_container_of(node
,
1317 struct lttng_session_trigger_list
,
1318 session_triggers_ht_node
);
1324 * Allocate an empty lttng_session_trigger_list for the session named
1327 * No ownership of 'session_name' is assumed by the session trigger list.
1328 * It is the caller's responsability to ensure the session name is alive
1329 * for as long as this list is.
1332 struct lttng_session_trigger_list
*lttng_session_trigger_list_create(
1333 const char *session_name
,
1334 struct cds_lfht
*session_triggers_ht
)
1336 struct lttng_session_trigger_list
*list
;
1338 list
= zmalloc(sizeof(*list
));
1342 list
->session_name
= session_name
;
1343 CDS_INIT_LIST_HEAD(&list
->list
);
1344 cds_lfht_node_init(&list
->session_triggers_ht_node
);
1345 list
->session_triggers_ht
= session_triggers_ht
;
1348 /* Publish the list through the session_triggers_ht. */
1349 cds_lfht_add(session_triggers_ht
,
1350 hash_key_str(session_name
, lttng_ht_seed
),
1351 &list
->session_triggers_ht_node
);
1358 void free_session_trigger_list_rcu(struct rcu_head
*node
)
1360 free(caa_container_of(node
, struct lttng_session_trigger_list
,
1365 void lttng_session_trigger_list_destroy(struct lttng_session_trigger_list
*list
)
1367 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1369 /* Empty the list element by element, and then free the list itself. */
1370 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1371 &list
->list
, node
) {
1372 cds_list_del(&trigger_list_element
->node
);
1373 free(trigger_list_element
);
1376 /* Unpublish the list from the session_triggers_ht. */
1377 cds_lfht_del(list
->session_triggers_ht
,
1378 &list
->session_triggers_ht_node
);
1380 call_rcu(&list
->rcu_node
, free_session_trigger_list_rcu
);
1384 int lttng_session_trigger_list_add(struct lttng_session_trigger_list
*list
,
1385 const struct lttng_trigger
*trigger
)
1388 struct lttng_trigger_list_element
*new_element
=
1389 zmalloc(sizeof(*new_element
));
1395 CDS_INIT_LIST_HEAD(&new_element
->node
);
1396 new_element
->trigger
= trigger
;
1397 cds_list_add(&new_element
->node
, &list
->list
);
1403 bool trigger_applies_to_session(const struct lttng_trigger
*trigger
,
1404 const char *session_name
)
1406 bool applies
= false;
1407 const struct lttng_condition
*condition
;
1409 condition
= lttng_trigger_get_const_condition(trigger
);
1410 switch (lttng_condition_get_type(condition
)) {
1411 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1412 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1414 enum lttng_condition_status condition_status
;
1415 const char *condition_session_name
;
1417 condition_status
= lttng_condition_session_rotation_get_session_name(
1418 condition
, &condition_session_name
);
1419 if (condition_status
!= LTTNG_CONDITION_STATUS_OK
) {
1420 ERR("[notification-thread] Failed to retrieve session rotation condition's session name");
1424 assert(condition_session_name
);
1425 applies
= !strcmp(condition_session_name
, session_name
);
1436 * Allocate and initialize an lttng_session_trigger_list which contains
1437 * all triggers that apply to the session named 'session_name'.
1439 * No ownership of 'session_name' is assumed by the session trigger list.
1440 * It is the caller's responsability to ensure the session name is alive
1441 * for as long as this list is.
1444 struct lttng_session_trigger_list
*lttng_session_trigger_list_build(
1445 const struct notification_thread_state
*state
,
1446 const char *session_name
)
1448 int trigger_count
= 0;
1449 struct lttng_session_trigger_list
*session_trigger_list
= NULL
;
1450 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1451 struct cds_lfht_iter iter
;
1453 session_trigger_list
= lttng_session_trigger_list_create(session_name
,
1454 state
->session_triggers_ht
);
1456 /* Add all triggers applying to the session named 'session_name'. */
1457 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1461 if (!trigger_applies_to_session(trigger_ht_element
->trigger
,
1466 ret
= lttng_session_trigger_list_add(session_trigger_list
,
1467 trigger_ht_element
->trigger
);
1475 DBG("[notification-thread] Found %i triggers that apply to newly created session",
1477 return session_trigger_list
;
1479 lttng_session_trigger_list_destroy(session_trigger_list
);
1484 struct session_info
*find_or_create_session_info(
1485 struct notification_thread_state
*state
,
1486 const char *name
, uid_t uid
, gid_t gid
)
1488 struct session_info
*session
= NULL
;
1489 struct cds_lfht_node
*node
;
1490 struct cds_lfht_iter iter
;
1491 struct lttng_session_trigger_list
*trigger_list
;
1494 cds_lfht_lookup(state
->sessions_ht
,
1495 hash_key_str(name
, lttng_ht_seed
),
1499 node
= cds_lfht_iter_get_node(&iter
);
1501 DBG("[notification-thread] Found session info of session \"%s\" (uid = %i, gid = %i)",
1503 session
= caa_container_of(node
, struct session_info
,
1505 assert(session
->uid
== uid
);
1506 assert(session
->gid
== gid
);
1507 session_info_get(session
);
1511 trigger_list
= lttng_session_trigger_list_build(state
, name
);
1512 if (!trigger_list
) {
1516 session
= session_info_create(name
, uid
, gid
, trigger_list
,
1517 state
->sessions_ht
);
1519 ERR("[notification-thread] Failed to allocation session info for session \"%s\" (uid = %i, gid = %i)",
1523 trigger_list
= NULL
;
1525 cds_lfht_add(state
->sessions_ht
, hash_key_str(name
, lttng_ht_seed
),
1526 &session
->sessions_ht_node
);
1532 session_info_put(session
);
1537 int handle_notification_thread_command_add_channel(
1538 struct notification_thread_state
*state
,
1539 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1540 const char *channel_name
, enum lttng_domain_type channel_domain
,
1541 uint64_t channel_key_int
, uint64_t channel_capacity
,
1542 enum lttng_error_code
*cmd_result
)
1544 struct cds_list_head trigger_list
;
1545 struct channel_info
*new_channel_info
= NULL
;
1546 struct channel_key channel_key
= {
1547 .key
= channel_key_int
,
1548 .domain
= channel_domain
,
1550 struct lttng_channel_trigger_list
*channel_trigger_list
= NULL
;
1551 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1552 int trigger_count
= 0;
1553 struct cds_lfht_iter iter
;
1554 struct session_info
*session_info
= NULL
;
1556 DBG("[notification-thread] Adding channel %s from session %s, channel key = %" PRIu64
" in %s domain",
1557 channel_name
, session_name
, channel_key_int
,
1558 channel_domain
== LTTNG_DOMAIN_KERNEL
? "kernel" : "user space");
1560 CDS_INIT_LIST_HEAD(&trigger_list
);
1562 session_info
= find_or_create_session_info(state
, session_name
,
1563 session_uid
, session_gid
);
1564 if (!session_info
) {
1565 /* Allocation error or an internal error occurred. */
1569 new_channel_info
= channel_info_create(channel_name
, &channel_key
,
1570 channel_capacity
, session_info
);
1571 if (!new_channel_info
) {
1576 /* Build a list of all triggers applying to the new channel. */
1577 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
1579 struct lttng_trigger_list_element
*new_element
;
1581 if (!trigger_applies_to_channel(trigger_ht_element
->trigger
,
1582 new_channel_info
)) {
1586 new_element
= zmalloc(sizeof(*new_element
));
1591 CDS_INIT_LIST_HEAD(&new_element
->node
);
1592 new_element
->trigger
= trigger_ht_element
->trigger
;
1593 cds_list_add(&new_element
->node
, &trigger_list
);
1598 DBG("[notification-thread] Found %i triggers that apply to newly added channel",
1600 channel_trigger_list
= zmalloc(sizeof(*channel_trigger_list
));
1601 if (!channel_trigger_list
) {
1604 channel_trigger_list
->channel_key
= new_channel_info
->key
;
1605 CDS_INIT_LIST_HEAD(&channel_trigger_list
->list
);
1606 cds_lfht_node_init(&channel_trigger_list
->channel_triggers_ht_node
);
1607 cds_list_splice(&trigger_list
, &channel_trigger_list
->list
);
1610 /* Add channel to the channel_ht which owns the channel_infos. */
1611 cds_lfht_add(state
->channels_ht
,
1612 hash_channel_key(&new_channel_info
->key
),
1613 &new_channel_info
->channels_ht_node
);
1615 * Add the list of triggers associated with this channel to the
1616 * channel_triggers_ht.
1618 cds_lfht_add(state
->channel_triggers_ht
,
1619 hash_channel_key(&new_channel_info
->key
),
1620 &channel_trigger_list
->channel_triggers_ht_node
);
1622 session_info_put(session_info
);
1623 *cmd_result
= LTTNG_OK
;
1626 channel_info_destroy(new_channel_info
);
1627 session_info_put(session_info
);
1632 void free_channel_trigger_list_rcu(struct rcu_head
*node
)
1634 free(caa_container_of(node
, struct lttng_channel_trigger_list
,
1639 void free_channel_state_sample_rcu(struct rcu_head
*node
)
1641 free(caa_container_of(node
, struct channel_state_sample
,
1646 int handle_notification_thread_command_remove_channel(
1647 struct notification_thread_state
*state
,
1648 uint64_t channel_key
, enum lttng_domain_type domain
,
1649 enum lttng_error_code
*cmd_result
)
1651 struct cds_lfht_node
*node
;
1652 struct cds_lfht_iter iter
;
1653 struct lttng_channel_trigger_list
*trigger_list
;
1654 struct lttng_trigger_list_element
*trigger_list_element
, *tmp
;
1655 struct channel_key key
= { .key
= channel_key
, .domain
= domain
};
1656 struct channel_info
*channel_info
;
1658 DBG("[notification-thread] Removing channel key = %" PRIu64
" in %s domain",
1659 channel_key
, domain
== LTTNG_DOMAIN_KERNEL
? "kernel" : "user space");
1663 cds_lfht_lookup(state
->channel_triggers_ht
,
1664 hash_channel_key(&key
),
1665 match_channel_trigger_list
,
1668 node
= cds_lfht_iter_get_node(&iter
);
1670 * There is a severe internal error if we are being asked to remove a
1671 * channel that doesn't exist.
1674 ERR("[notification-thread] Channel being removed is unknown to the notification thread");
1678 /* Free the list of triggers associated with this channel. */
1679 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
1680 channel_triggers_ht_node
);
1681 cds_list_for_each_entry_safe(trigger_list_element
, tmp
,
1682 &trigger_list
->list
, node
) {
1683 cds_list_del(&trigger_list_element
->node
);
1684 free(trigger_list_element
);
1686 cds_lfht_del(state
->channel_triggers_ht
, node
);
1687 call_rcu(&trigger_list
->rcu_node
, free_channel_trigger_list_rcu
);
1689 /* Free sampled channel state. */
1690 cds_lfht_lookup(state
->channel_state_ht
,
1691 hash_channel_key(&key
),
1692 match_channel_state_sample
,
1695 node
= cds_lfht_iter_get_node(&iter
);
1697 * This is expected to be NULL if the channel is destroyed before we
1698 * received a sample.
1701 struct channel_state_sample
*sample
= caa_container_of(node
,
1702 struct channel_state_sample
,
1703 channel_state_ht_node
);
1705 cds_lfht_del(state
->channel_state_ht
, node
);
1706 call_rcu(&sample
->rcu_node
, free_channel_state_sample_rcu
);
1709 /* Remove the channel from the channels_ht and free it. */
1710 cds_lfht_lookup(state
->channels_ht
,
1711 hash_channel_key(&key
),
1715 node
= cds_lfht_iter_get_node(&iter
);
1717 channel_info
= caa_container_of(node
, struct channel_info
,
1719 cds_lfht_del(state
->channels_ht
, node
);
1720 channel_info_destroy(channel_info
);
1723 *cmd_result
= LTTNG_OK
;
1728 int handle_notification_thread_command_session_rotation(
1729 struct notification_thread_state
*state
,
1730 enum notification_thread_command_type cmd_type
,
1731 const char *session_name
, uid_t session_uid
, gid_t session_gid
,
1732 uint64_t trace_archive_chunk_id
,
1733 struct lttng_trace_archive_location
*location
,
1734 enum lttng_error_code
*_cmd_result
)
1737 enum lttng_error_code cmd_result
= LTTNG_OK
;
1738 struct lttng_session_trigger_list
*trigger_list
;
1739 struct lttng_trigger_list_element
*trigger_list_element
;
1740 struct session_info
*session_info
;
1744 session_info
= find_or_create_session_info(state
, session_name
,
1745 session_uid
, session_gid
);
1746 if (!session_info
) {
1747 /* Allocation error or an internal error occurred. */
1749 cmd_result
= LTTNG_ERR_NOMEM
;
1753 session_info
->rotation
.ongoing
=
1754 cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
;
1755 session_info
->rotation
.id
= trace_archive_chunk_id
;
1756 trigger_list
= get_session_trigger_list(state
, session_name
);
1757 if (!trigger_list
) {
1758 DBG("[notification-thread] No triggers applying to session \"%s\" found",
1763 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
1765 const struct lttng_condition
*condition
;
1766 const struct lttng_action
*action
;
1767 const struct lttng_trigger
*trigger
;
1768 struct notification_client_list
*client_list
;
1769 struct lttng_evaluation
*evaluation
= NULL
;
1770 enum lttng_condition_type condition_type
;
1772 trigger
= trigger_list_element
->trigger
;
1773 condition
= lttng_trigger_get_const_condition(trigger
);
1775 condition_type
= lttng_condition_get_type(condition
);
1777 if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
&&
1778 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1780 } else if (condition_type
== LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
&&
1781 cmd_type
!= NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
) {
1785 action
= lttng_trigger_get_const_action(trigger
);
1787 /* Notify actions are the only type currently supported. */
1788 assert(lttng_action_get_type_const(action
) ==
1789 LTTNG_ACTION_TYPE_NOTIFY
);
1791 client_list
= get_client_list_from_condition(state
, condition
);
1792 assert(client_list
);
1794 if (cds_list_empty(&client_list
->list
)) {
1796 * No clients interested in the evaluation's result,
1802 if (cmd_type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
) {
1803 evaluation
= lttng_evaluation_session_rotation_ongoing_create(
1804 trace_archive_chunk_id
);
1806 evaluation
= lttng_evaluation_session_rotation_completed_create(
1807 trace_archive_chunk_id
, location
);
1811 /* Internal error */
1813 cmd_result
= LTTNG_ERR_UNK
;
1817 /* Dispatch evaluation result to all clients. */
1818 ret
= send_evaluation_to_clients(trigger_list_element
->trigger
,
1819 evaluation
, client_list
, state
,
1822 lttng_evaluation_destroy(evaluation
);
1823 if (caa_unlikely(ret
)) {
1828 session_info_put(session_info
);
1829 *_cmd_result
= cmd_result
;
1835 int condition_is_supported(struct lttng_condition
*condition
)
1839 switch (lttng_condition_get_type(condition
)) {
1840 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
1841 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
1843 enum lttng_domain_type domain
;
1845 ret
= lttng_condition_buffer_usage_get_domain_type(condition
,
1852 if (domain
!= LTTNG_DOMAIN_KERNEL
) {
1858 * Older kernel tracers don't expose the API to monitor their
1859 * buffers. Therefore, we reject triggers that require that
1860 * mechanism to be available to be evaluated.
1862 ret
= kernel_supports_ring_buffer_snapshot_sample_positions(
1873 /* Must be called with RCU read lock held. */
1875 int bind_trigger_to_matching_session(const struct lttng_trigger
*trigger
,
1876 struct notification_thread_state
*state
)
1879 const struct lttng_condition
*condition
;
1880 const char *session_name
;
1881 struct lttng_session_trigger_list
*trigger_list
;
1883 condition
= lttng_trigger_get_const_condition(trigger
);
1884 switch (lttng_condition_get_type(condition
)) {
1885 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_ONGOING
:
1886 case LTTNG_CONDITION_TYPE_SESSION_ROTATION_COMPLETED
:
1888 enum lttng_condition_status status
;
1890 status
= lttng_condition_session_rotation_get_session_name(
1891 condition
, &session_name
);
1892 if (status
!= LTTNG_CONDITION_STATUS_OK
) {
1893 ERR("[notification-thread] Failed to bind trigger to session: unable to get 'session_rotation' condition's session name");
1904 trigger_list
= get_session_trigger_list(state
, session_name
);
1905 if (!trigger_list
) {
1906 DBG("[notification-thread] Unable to bind trigger applying to session \"%s\" as it is not yet known to the notification system",
1912 DBG("[notification-thread] Newly registered trigger bound to session \"%s\"",
1914 ret
= lttng_session_trigger_list_add(trigger_list
, trigger
);
1919 /* Must be called with RCU read lock held. */
1921 int bind_trigger_to_matching_channels(const struct lttng_trigger
*trigger
,
1922 struct notification_thread_state
*state
)
1925 struct cds_lfht_node
*node
;
1926 struct cds_lfht_iter iter
;
1927 struct channel_info
*channel
;
1929 cds_lfht_for_each_entry(state
->channels_ht
, &iter
, channel
,
1931 struct lttng_trigger_list_element
*trigger_list_element
;
1932 struct lttng_channel_trigger_list
*trigger_list
;
1934 if (!trigger_applies_to_channel(trigger
, channel
)) {
1938 cds_lfht_lookup(state
->channel_triggers_ht
,
1939 hash_channel_key(&channel
->key
),
1940 match_channel_trigger_list
,
1943 node
= cds_lfht_iter_get_node(&iter
);
1945 trigger_list
= caa_container_of(node
,
1946 struct lttng_channel_trigger_list
,
1947 channel_triggers_ht_node
);
1949 trigger_list_element
= zmalloc(sizeof(*trigger_list_element
));
1950 if (!trigger_list_element
) {
1954 CDS_INIT_LIST_HEAD(&trigger_list_element
->node
);
1955 trigger_list_element
->trigger
= trigger
;
1956 cds_list_add(&trigger_list_element
->node
, &trigger_list
->list
);
1957 DBG("[notification-thread] Newly registered trigger bound to channel \"%s\"",
1965 * FIXME A client's credentials are not checked when registering a trigger, nor
1966 * are they stored alongside with the trigger.
1968 * The effects of this are benign since:
1969 * - The client will succeed in registering the trigger, as it is valid,
1970 * - The trigger will, internally, be bound to the channel/session,
1971 * - The notifications will not be sent since the client's credentials
1972 * are checked against the channel at that moment.
1974 * If this function returns a non-zero value, it means something is
1975 * fundamentally broken and the whole subsystem/thread will be torn down.
1977 * If a non-fatal error occurs, just set the cmd_result to the appropriate
1981 int handle_notification_thread_command_register_trigger(
1982 struct notification_thread_state
*state
,
1983 struct lttng_trigger
*trigger
,
1984 enum lttng_error_code
*cmd_result
)
1987 struct lttng_condition
*condition
;
1988 struct notification_client
*client
;
1989 struct notification_client_list
*client_list
= NULL
;
1990 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
1991 struct notification_client_list_element
*client_list_element
, *tmp
;
1992 struct cds_lfht_node
*node
;
1993 struct cds_lfht_iter iter
;
1994 bool free_trigger
= true;
1998 condition
= lttng_trigger_get_condition(trigger
);
2001 ret
= condition_is_supported(condition
);
2004 } else if (ret
== 0) {
2005 *cmd_result
= LTTNG_ERR_NOT_SUPPORTED
;
2008 /* Feature is supported, continue. */
2012 trigger_ht_element
= zmalloc(sizeof(*trigger_ht_element
));
2013 if (!trigger_ht_element
) {
2018 /* Add trigger to the trigger_ht. */
2019 cds_lfht_node_init(&trigger_ht_element
->node
);
2020 trigger_ht_element
->trigger
= trigger
;
2022 node
= cds_lfht_add_unique(state
->triggers_ht
,
2023 lttng_condition_hash(condition
),
2026 &trigger_ht_element
->node
);
2027 if (node
!= &trigger_ht_element
->node
) {
2028 /* Not a fatal error, simply report it to the client. */
2029 *cmd_result
= LTTNG_ERR_TRIGGER_EXISTS
;
2030 goto error_free_ht_element
;
2034 * Ownership of the trigger and of its wrapper was transfered to
2037 trigger_ht_element
= NULL
;
2038 free_trigger
= false;
2041 * The rest only applies to triggers that have a "notify" action.
2042 * It is not skipped as this is the only action type currently
2045 client_list
= zmalloc(sizeof(*client_list
));
2048 goto error_free_ht_element
;
2050 cds_lfht_node_init(&client_list
->notification_trigger_ht_node
);
2051 CDS_INIT_LIST_HEAD(&client_list
->list
);
2052 client_list
->trigger
= trigger
;
2054 /* Build a list of clients to which this new trigger applies. */
2055 cds_lfht_for_each_entry(state
->client_socket_ht
, &iter
, client
,
2056 client_socket_ht_node
) {
2057 if (!trigger_applies_to_client(trigger
, client
)) {
2061 client_list_element
= zmalloc(sizeof(*client_list_element
));
2062 if (!client_list_element
) {
2064 goto error_free_client_list
;
2066 CDS_INIT_LIST_HEAD(&client_list_element
->node
);
2067 client_list_element
->client
= client
;
2068 cds_list_add(&client_list_element
->node
, &client_list
->list
);
2071 cds_lfht_add(state
->notification_trigger_clients_ht
,
2072 lttng_condition_hash(condition
),
2073 &client_list
->notification_trigger_ht_node
);
2075 switch (get_condition_binding_object(condition
)) {
2076 case LTTNG_OBJECT_TYPE_SESSION
:
2077 /* Add the trigger to the list if it matches a known session. */
2078 ret
= bind_trigger_to_matching_session(trigger
, state
);
2080 goto error_free_client_list
;
2083 case LTTNG_OBJECT_TYPE_CHANNEL
:
2085 * Add the trigger to list of triggers bound to the channels
2088 ret
= bind_trigger_to_matching_channels(trigger
, state
);
2090 goto error_free_client_list
;
2093 case LTTNG_OBJECT_TYPE_NONE
:
2096 ERR("[notification-thread] Unknown object type on which to bind a newly registered trigger was encountered");
2098 goto error_free_client_list
;
2102 * Since there is nothing preventing clients from subscribing to a
2103 * condition before the corresponding trigger is registered, we have
2104 * to evaluate this new condition right away.
2106 * At some point, we were waiting for the next "evaluation" (e.g. on
2107 * reception of a channel sample) to evaluate this new condition, but
2110 * The reason it was broken is that waiting for the next sample
2111 * does not allow us to properly handle transitions for edge-triggered
2114 * Consider this example: when we handle a new channel sample, we
2115 * evaluate each conditions twice: once with the previous state, and
2116 * again with the newest state. We then use those two results to
2117 * determine whether a state change happened: a condition was false and
2118 * became true. If a state change happened, we have to notify clients.
2120 * Now, if a client subscribes to a given notification and registers
2121 * a trigger *after* that subscription, we have to make sure the
2122 * condition is evaluated at this point while considering only the
2123 * current state. Otherwise, the next evaluation cycle may only see
2124 * that the evaluations remain the same (true for samples n-1 and n) and
2125 * the client will never know that the condition has been met.
2127 cds_list_for_each_entry_safe(client_list_element
, tmp
,
2128 &client_list
->list
, node
) {
2129 ret
= evaluate_condition_for_client(trigger
, condition
,
2130 client_list_element
->client
, state
);
2132 goto error_free_client_list
;
2137 * Client list ownership transferred to the
2138 * notification_trigger_clients_ht.
2142 *cmd_result
= LTTNG_OK
;
2143 error_free_client_list
:
2145 cds_list_for_each_entry_safe(client_list_element
, tmp
,
2146 &client_list
->list
, node
) {
2147 free(client_list_element
);
2151 error_free_ht_element
:
2152 free(trigger_ht_element
);
2155 struct lttng_action
*action
= lttng_trigger_get_action(trigger
);
2157 lttng_condition_destroy(condition
);
2158 lttng_action_destroy(action
);
2159 lttng_trigger_destroy(trigger
);
2166 void free_notification_client_list_rcu(struct rcu_head
*node
)
2168 free(caa_container_of(node
, struct notification_client_list
,
2173 void free_lttng_trigger_ht_element_rcu(struct rcu_head
*node
)
2175 free(caa_container_of(node
, struct lttng_trigger_ht_element
,
2180 int handle_notification_thread_command_unregister_trigger(
2181 struct notification_thread_state
*state
,
2182 struct lttng_trigger
*trigger
,
2183 enum lttng_error_code
*_cmd_reply
)
2185 struct cds_lfht_iter iter
;
2186 struct cds_lfht_node
*triggers_ht_node
;
2187 struct lttng_channel_trigger_list
*trigger_list
;
2188 struct notification_client_list
*client_list
;
2189 struct notification_client_list_element
*client_list_element
, *tmp
;
2190 struct lttng_trigger_ht_element
*trigger_ht_element
= NULL
;
2191 struct lttng_condition
*condition
= lttng_trigger_get_condition(
2193 struct lttng_action
*action
;
2194 enum lttng_error_code cmd_reply
;
2198 cds_lfht_lookup(state
->triggers_ht
,
2199 lttng_condition_hash(condition
),
2203 triggers_ht_node
= cds_lfht_iter_get_node(&iter
);
2204 if (!triggers_ht_node
) {
2205 cmd_reply
= LTTNG_ERR_TRIGGER_NOT_FOUND
;
2208 cmd_reply
= LTTNG_OK
;
2211 /* Remove trigger from channel_triggers_ht. */
2212 cds_lfht_for_each_entry(state
->channel_triggers_ht
, &iter
, trigger_list
,
2213 channel_triggers_ht_node
) {
2214 struct lttng_trigger_list_element
*trigger_element
, *tmp
;
2216 cds_list_for_each_entry_safe(trigger_element
, tmp
,
2217 &trigger_list
->list
, node
) {
2218 const struct lttng_condition
*current_condition
=
2219 lttng_trigger_get_const_condition(
2220 trigger_element
->trigger
);
2222 assert(current_condition
);
2223 if (!lttng_condition_is_equal(condition
,
2224 current_condition
)) {
2228 DBG("[notification-thread] Removed trigger from channel_triggers_ht");
2229 cds_list_del(&trigger_element
->node
);
2230 /* A trigger can only appear once per channel */
2236 * Remove and release the client list from
2237 * notification_trigger_clients_ht.
2239 client_list
= get_client_list_from_condition(state
, condition
);
2240 assert(client_list
);
2242 cds_list_for_each_entry_safe(client_list_element
, tmp
,
2243 &client_list
->list
, node
) {
2244 free(client_list_element
);
2246 cds_lfht_del(state
->notification_trigger_clients_ht
,
2247 &client_list
->notification_trigger_ht_node
);
2248 call_rcu(&client_list
->rcu_node
, free_notification_client_list_rcu
);
2250 /* Remove trigger from triggers_ht. */
2251 trigger_ht_element
= caa_container_of(triggers_ht_node
,
2252 struct lttng_trigger_ht_element
, node
);
2253 cds_lfht_del(state
->triggers_ht
, triggers_ht_node
);
2255 condition
= lttng_trigger_get_condition(trigger_ht_element
->trigger
);
2256 lttng_condition_destroy(condition
);
2257 action
= lttng_trigger_get_action(trigger_ht_element
->trigger
);
2258 lttng_action_destroy(action
);
2259 lttng_trigger_destroy(trigger_ht_element
->trigger
);
2260 call_rcu(&trigger_ht_element
->rcu_node
, free_lttng_trigger_ht_element_rcu
);
2264 *_cmd_reply
= cmd_reply
;
2269 /* Returns 0 on success, 1 on exit requested, negative value on error. */
2270 int handle_notification_thread_command(
2271 struct notification_thread_handle
*handle
,
2272 struct notification_thread_state
*state
)
2276 struct notification_thread_command
*cmd
;
2278 /* Read the event pipe to put it back into a quiescent state. */
2279 ret
= read(lttng_pipe_get_readfd(handle
->cmd_queue
.event_pipe
), &counter
,
2285 pthread_mutex_lock(&handle
->cmd_queue
.lock
);
2286 cmd
= cds_list_first_entry(&handle
->cmd_queue
.list
,
2287 struct notification_thread_command
, cmd_list_node
);
2288 switch (cmd
->type
) {
2289 case NOTIFICATION_COMMAND_TYPE_REGISTER_TRIGGER
:
2290 DBG("[notification-thread] Received register trigger command");
2291 ret
= handle_notification_thread_command_register_trigger(
2292 state
, cmd
->parameters
.trigger
,
2295 case NOTIFICATION_COMMAND_TYPE_UNREGISTER_TRIGGER
:
2296 DBG("[notification-thread] Received unregister trigger command");
2297 ret
= handle_notification_thread_command_unregister_trigger(
2298 state
, cmd
->parameters
.trigger
,
2301 case NOTIFICATION_COMMAND_TYPE_ADD_CHANNEL
:
2302 DBG("[notification-thread] Received add channel command");
2303 ret
= handle_notification_thread_command_add_channel(
2305 cmd
->parameters
.add_channel
.session
.name
,
2306 cmd
->parameters
.add_channel
.session
.uid
,
2307 cmd
->parameters
.add_channel
.session
.gid
,
2308 cmd
->parameters
.add_channel
.channel
.name
,
2309 cmd
->parameters
.add_channel
.channel
.domain
,
2310 cmd
->parameters
.add_channel
.channel
.key
,
2311 cmd
->parameters
.add_channel
.channel
.capacity
,
2314 case NOTIFICATION_COMMAND_TYPE_REMOVE_CHANNEL
:
2315 DBG("[notification-thread] Received remove channel command");
2316 ret
= handle_notification_thread_command_remove_channel(
2317 state
, cmd
->parameters
.remove_channel
.key
,
2318 cmd
->parameters
.remove_channel
.domain
,
2321 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
:
2322 case NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_COMPLETED
:
2323 DBG("[notification-thread] Received session rotation %s command",
2324 cmd
->type
== NOTIFICATION_COMMAND_TYPE_SESSION_ROTATION_ONGOING
?
2325 "ongoing" : "completed");
2326 ret
= handle_notification_thread_command_session_rotation(
2329 cmd
->parameters
.session_rotation
.session_name
,
2330 cmd
->parameters
.session_rotation
.uid
,
2331 cmd
->parameters
.session_rotation
.gid
,
2332 cmd
->parameters
.session_rotation
.trace_archive_chunk_id
,
2333 cmd
->parameters
.session_rotation
.location
,
2336 case NOTIFICATION_COMMAND_TYPE_QUIT
:
2337 DBG("[notification-thread] Received quit command");
2338 cmd
->reply_code
= LTTNG_OK
;
2342 ERR("[notification-thread] Unknown internal command received");
2350 cds_list_del(&cmd
->cmd_list_node
);
2351 lttng_waiter_wake_up(&cmd
->reply_waiter
);
2352 pthread_mutex_unlock(&handle
->cmd_queue
.lock
);
2355 /* Wake-up and return a fatal error to the calling thread. */
2356 lttng_waiter_wake_up(&cmd
->reply_waiter
);
2357 pthread_mutex_unlock(&handle
->cmd_queue
.lock
);
2358 cmd
->reply_code
= LTTNG_ERR_FATAL
;
2360 /* Indicate a fatal error to the caller. */
2365 unsigned long hash_client_socket(int socket
)
2367 return hash_key_ulong((void *) (unsigned long) socket
, lttng_ht_seed
);
2371 int socket_set_non_blocking(int socket
)
2375 /* Set the pipe as non-blocking. */
2376 ret
= fcntl(socket
, F_GETFL
, 0);
2378 PERROR("fcntl get socket flags");
2383 ret
= fcntl(socket
, F_SETFL
, flags
| O_NONBLOCK
);
2385 PERROR("fcntl set O_NONBLOCK socket flag");
2388 DBG("Client socket (fd = %i) set as non-blocking", socket
);
2394 int client_reset_inbound_state(struct notification_client
*client
)
2398 ret
= lttng_dynamic_buffer_set_size(
2399 &client
->communication
.inbound
.buffer
, 0);
2402 client
->communication
.inbound
.bytes_to_receive
=
2403 sizeof(struct lttng_notification_channel_message
);
2404 client
->communication
.inbound
.msg_type
=
2405 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
;
2406 LTTNG_SOCK_SET_UID_CRED(&client
->communication
.inbound
.creds
, -1);
2407 LTTNG_SOCK_SET_GID_CRED(&client
->communication
.inbound
.creds
, -1);
2408 ret
= lttng_dynamic_buffer_set_size(
2409 &client
->communication
.inbound
.buffer
,
2410 client
->communication
.inbound
.bytes_to_receive
);
2414 int handle_notification_thread_client_connect(
2415 struct notification_thread_state
*state
)
2418 struct notification_client
*client
;
2420 DBG("[notification-thread] Handling new notification channel client connection");
2422 client
= zmalloc(sizeof(*client
));
2428 CDS_INIT_LIST_HEAD(&client
->condition_list
);
2429 lttng_dynamic_buffer_init(&client
->communication
.inbound
.buffer
);
2430 lttng_dynamic_buffer_init(&client
->communication
.outbound
.buffer
);
2431 client
->communication
.inbound
.expect_creds
= true;
2432 ret
= client_reset_inbound_state(client
);
2434 ERR("[notification-thread] Failed to reset client communication's inbound state");
2439 ret
= lttcomm_accept_unix_sock(state
->notification_channel_socket
);
2441 ERR("[notification-thread] Failed to accept new notification channel client connection");
2446 client
->socket
= ret
;
2448 ret
= socket_set_non_blocking(client
->socket
);
2450 ERR("[notification-thread] Failed to set new notification channel client connection socket as non-blocking");
2454 ret
= lttcomm_setsockopt_creds_unix_sock(client
->socket
);
2456 ERR("[notification-thread] Failed to set socket options on new notification channel client socket");
2461 ret
= lttng_poll_add(&state
->events
, client
->socket
,
2462 LPOLLIN
| LPOLLERR
|
2463 LPOLLHUP
| LPOLLRDHUP
);
2465 ERR("[notification-thread] Failed to add notification channel client socket to poll set");
2469 DBG("[notification-thread] Added new notification channel client socket (%i) to poll set",
2473 cds_lfht_add(state
->client_socket_ht
,
2474 hash_client_socket(client
->socket
),
2475 &client
->client_socket_ht_node
);
2480 notification_client_destroy(client
, state
);
2484 int handle_notification_thread_client_disconnect(
2486 struct notification_thread_state
*state
)
2489 struct notification_client
*client
;
2492 DBG("[notification-thread] Closing client connection (socket fd = %i)",
2494 client
= get_client_from_socket(client_socket
, state
);
2496 /* Internal state corruption, fatal error. */
2497 ERR("[notification-thread] Unable to find client (socket fd = %i)",
2503 ret
= lttng_poll_del(&state
->events
, client_socket
);
2505 ERR("[notification-thread] Failed to remove client socket from poll set");
2507 cds_lfht_del(state
->client_socket_ht
,
2508 &client
->client_socket_ht_node
);
2509 notification_client_destroy(client
, state
);
2515 int handle_notification_thread_client_disconnect_all(
2516 struct notification_thread_state
*state
)
2518 struct cds_lfht_iter iter
;
2519 struct notification_client
*client
;
2520 bool error_encoutered
= false;
2523 DBG("[notification-thread] Closing all client connections");
2524 cds_lfht_for_each_entry(state
->client_socket_ht
, &iter
, client
,
2525 client_socket_ht_node
) {
2528 ret
= handle_notification_thread_client_disconnect(
2529 client
->socket
, state
);
2531 error_encoutered
= true;
2535 return error_encoutered
? 1 : 0;
2538 int handle_notification_thread_trigger_unregister_all(
2539 struct notification_thread_state
*state
)
2541 bool error_occurred
= false;
2542 struct cds_lfht_iter iter
;
2543 struct lttng_trigger_ht_element
*trigger_ht_element
;
2545 cds_lfht_for_each_entry(state
->triggers_ht
, &iter
, trigger_ht_element
,
2547 int ret
= handle_notification_thread_command_unregister_trigger(
2548 state
, trigger_ht_element
->trigger
, NULL
);
2550 error_occurred
= true;
2553 return error_occurred
? -1 : 0;
2557 int client_flush_outgoing_queue(struct notification_client
*client
,
2558 struct notification_thread_state
*state
)
2561 size_t to_send_count
;
2563 assert(client
->communication
.outbound
.buffer
.size
!= 0);
2564 to_send_count
= client
->communication
.outbound
.buffer
.size
;
2565 DBG("[notification-thread] Flushing client (socket fd = %i) outgoing queue",
2568 ret
= lttcomm_send_unix_sock_non_block(client
->socket
,
2569 client
->communication
.outbound
.buffer
.data
,
2571 if ((ret
< 0 && (errno
== EAGAIN
|| errno
== EWOULDBLOCK
)) ||
2572 (ret
> 0 && ret
< to_send_count
)) {
2573 DBG("[notification-thread] Client (socket fd = %i) outgoing queue could not be completely flushed",
2575 to_send_count
-= max(ret
, 0);
2577 memcpy(client
->communication
.outbound
.buffer
.data
,
2578 client
->communication
.outbound
.buffer
.data
+
2579 client
->communication
.outbound
.buffer
.size
- to_send_count
,
2581 ret
= lttng_dynamic_buffer_set_size(
2582 &client
->communication
.outbound
.buffer
,
2589 * We want to be notified whenever there is buffer space
2590 * available to send the rest of the payload.
2592 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
2593 CLIENT_POLL_MASK_IN_OUT
);
2597 } else if (ret
< 0) {
2598 /* Generic error, disconnect the client. */
2599 ERR("[notification-thread] Failed to send flush outgoing queue, disconnecting client (socket fd = %i)",
2601 ret
= handle_notification_thread_client_disconnect(
2602 client
->socket
, state
);
2607 /* No error and flushed the queue completely. */
2608 ret
= lttng_dynamic_buffer_set_size(
2609 &client
->communication
.outbound
.buffer
, 0);
2613 ret
= lttng_poll_mod(&state
->events
, client
->socket
,
2614 CLIENT_POLL_MASK_IN
);
2619 client
->communication
.outbound
.queued_command_reply
= false;
2620 client
->communication
.outbound
.dropped_notification
= false;
2629 int client_send_command_reply(struct notification_client
*client
,
2630 struct notification_thread_state
*state
,
2631 enum lttng_notification_channel_status status
)
2634 struct lttng_notification_channel_command_reply reply
= {
2635 .status
= (int8_t) status
,
2637 struct lttng_notification_channel_message msg
= {
2638 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_COMMAND_REPLY
,
2639 .size
= sizeof(reply
),
2641 char buffer
[sizeof(msg
) + sizeof(reply
)];
2643 if (client
->communication
.outbound
.queued_command_reply
) {
2644 /* Protocol error. */
2648 memcpy(buffer
, &msg
, sizeof(msg
));
2649 memcpy(buffer
+ sizeof(msg
), &reply
, sizeof(reply
));
2650 DBG("[notification-thread] Send command reply (%i)", (int) status
);
2652 /* Enqueue buffer to outgoing queue and flush it. */
2653 ret
= lttng_dynamic_buffer_append(
2654 &client
->communication
.outbound
.buffer
,
2655 buffer
, sizeof(buffer
));
2660 ret
= client_flush_outgoing_queue(client
, state
);
2665 if (client
->communication
.outbound
.buffer
.size
!= 0) {
2666 /* Queue could not be emptied. */
2667 client
->communication
.outbound
.queued_command_reply
= true;
2676 int client_dispatch_message(struct notification_client
*client
,
2677 struct notification_thread_state
*state
)
2681 if (client
->communication
.inbound
.msg_type
!=
2682 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
&&
2683 client
->communication
.inbound
.msg_type
!=
2684 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
&&
2685 !client
->validated
) {
2686 WARN("[notification-thread] client attempted a command before handshake");
2691 switch (client
->communication
.inbound
.msg_type
) {
2692 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNKNOWN
:
2695 * Receiving message header. The function will be called again
2696 * once the rest of the message as been received and can be
2699 const struct lttng_notification_channel_message
*msg
;
2701 assert(sizeof(*msg
) ==
2702 client
->communication
.inbound
.buffer
.size
);
2703 msg
= (const struct lttng_notification_channel_message
*)
2704 client
->communication
.inbound
.buffer
.data
;
2706 if (msg
->size
== 0 || msg
->size
> DEFAULT_MAX_NOTIFICATION_CLIENT_MESSAGE_PAYLOAD_SIZE
) {
2707 ERR("[notification-thread] Invalid notification channel message: length = %u", msg
->size
);
2712 switch (msg
->type
) {
2713 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
2714 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
2715 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
2719 ERR("[notification-thread] Invalid notification channel message: unexpected message type");
2723 client
->communication
.inbound
.bytes_to_receive
= msg
->size
;
2724 client
->communication
.inbound
.msg_type
=
2725 (enum lttng_notification_channel_message_type
) msg
->type
;
2726 ret
= lttng_dynamic_buffer_set_size(
2727 &client
->communication
.inbound
.buffer
, msg
->size
);
2733 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
:
2735 struct lttng_notification_channel_command_handshake
*handshake_client
;
2736 struct lttng_notification_channel_command_handshake handshake_reply
= {
2737 .major
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
,
2738 .minor
= LTTNG_NOTIFICATION_CHANNEL_VERSION_MINOR
,
2740 struct lttng_notification_channel_message msg_header
= {
2741 .type
= LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_HANDSHAKE
,
2742 .size
= sizeof(handshake_reply
),
2744 enum lttng_notification_channel_status status
=
2745 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
2746 char send_buffer
[sizeof(msg_header
) + sizeof(handshake_reply
)];
2748 memcpy(send_buffer
, &msg_header
, sizeof(msg_header
));
2749 memcpy(send_buffer
+ sizeof(msg_header
), &handshake_reply
,
2750 sizeof(handshake_reply
));
2753 (struct lttng_notification_channel_command_handshake
*)
2754 client
->communication
.inbound
.buffer
.data
;
2755 client
->major
= handshake_client
->major
;
2756 client
->minor
= handshake_client
->minor
;
2757 if (!client
->communication
.inbound
.creds_received
) {
2758 ERR("[notification-thread] No credentials received from client");
2763 client
->uid
= LTTNG_SOCK_GET_UID_CRED(
2764 &client
->communication
.inbound
.creds
);
2765 client
->gid
= LTTNG_SOCK_GET_GID_CRED(
2766 &client
->communication
.inbound
.creds
);
2767 DBG("[notification-thread] Received handshake from client (uid = %u, gid = %u) with version %i.%i",
2768 client
->uid
, client
->gid
, (int) client
->major
,
2769 (int) client
->minor
);
2771 if (handshake_client
->major
!= LTTNG_NOTIFICATION_CHANNEL_VERSION_MAJOR
) {
2772 status
= LTTNG_NOTIFICATION_CHANNEL_STATUS_UNSUPPORTED_VERSION
;
2775 ret
= lttng_dynamic_buffer_append(&client
->communication
.outbound
.buffer
,
2776 send_buffer
, sizeof(send_buffer
));
2778 ERR("[notification-thread] Failed to send protocol version to notification channel client");
2782 ret
= client_flush_outgoing_queue(client
, state
);
2787 ret
= client_send_command_reply(client
, state
, status
);
2789 ERR("[notification-thread] Failed to send reply to notification channel client");
2793 /* Set reception state to receive the next message header. */
2794 ret
= client_reset_inbound_state(client
);
2796 ERR("[notification-thread] Failed to reset client communication's inbound state");
2799 client
->validated
= true;
2802 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
:
2803 case LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_UNSUBSCRIBE
:
2805 struct lttng_condition
*condition
;
2806 enum lttng_notification_channel_status status
=
2807 LTTNG_NOTIFICATION_CHANNEL_STATUS_OK
;
2808 const struct lttng_buffer_view condition_view
=
2809 lttng_buffer_view_from_dynamic_buffer(
2810 &client
->communication
.inbound
.buffer
,
2812 size_t expected_condition_size
=
2813 client
->communication
.inbound
.buffer
.size
;
2815 ret
= lttng_condition_create_from_buffer(&condition_view
,
2817 if (ret
!= expected_condition_size
) {
2818 ERR("[notification-thread] Malformed condition received from client");
2822 if (client
->communication
.inbound
.msg_type
==
2823 LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_SUBSCRIBE
) {
2824 ret
= notification_thread_client_subscribe(client
,
2825 condition
, state
, &status
);
2827 ret
= notification_thread_client_unsubscribe(client
,
2828 condition
, state
, &status
);
2834 ret
= client_send_command_reply(client
, state
, status
);
2836 ERR("[notification-thread] Failed to send reply to notification channel client");
2840 /* Set reception state to receive the next message header. */
2841 ret
= client_reset_inbound_state(client
);
2843 ERR("[notification-thread] Failed to reset client communication's inbound state");
2855 /* Incoming data from client. */
2856 int handle_notification_thread_client_in(
2857 struct notification_thread_state
*state
, int socket
)
2860 struct notification_client
*client
;
2864 client
= get_client_from_socket(socket
, state
);
2866 /* Internal error, abort. */
2871 offset
= client
->communication
.inbound
.buffer
.size
-
2872 client
->communication
.inbound
.bytes_to_receive
;
2873 if (client
->communication
.inbound
.expect_creds
) {
2874 recv_ret
= lttcomm_recv_creds_unix_sock(socket
,
2875 client
->communication
.inbound
.buffer
.data
+ offset
,
2876 client
->communication
.inbound
.bytes_to_receive
,
2877 &client
->communication
.inbound
.creds
);
2879 client
->communication
.inbound
.expect_creds
= false;
2880 client
->communication
.inbound
.creds_received
= true;
2883 recv_ret
= lttcomm_recv_unix_sock_non_block(socket
,
2884 client
->communication
.inbound
.buffer
.data
+ offset
,
2885 client
->communication
.inbound
.bytes_to_receive
);
2888 goto error_disconnect_client
;
2891 client
->communication
.inbound
.bytes_to_receive
-= recv_ret
;
2892 if (client
->communication
.inbound
.bytes_to_receive
== 0) {
2893 ret
= client_dispatch_message(client
, state
);
2896 * Only returns an error if this client must be
2899 goto error_disconnect_client
;
2906 error_disconnect_client
:
2907 ret
= handle_notification_thread_client_disconnect(socket
, state
);
2911 /* Client ready to receive outgoing data. */
2912 int handle_notification_thread_client_out(
2913 struct notification_thread_state
*state
, int socket
)
2916 struct notification_client
*client
;
2918 client
= get_client_from_socket(socket
, state
);
2920 /* Internal error, abort. */
2925 ret
= client_flush_outgoing_queue(client
, state
);
2934 bool evaluate_buffer_usage_condition(const struct lttng_condition
*condition
,
2935 const struct channel_state_sample
*sample
,
2936 uint64_t buffer_capacity
)
2938 bool result
= false;
2940 enum lttng_condition_type condition_type
;
2941 const struct lttng_condition_buffer_usage
*use_condition
= container_of(
2942 condition
, struct lttng_condition_buffer_usage
,
2945 if (use_condition
->threshold_bytes
.set
) {
2946 threshold
= use_condition
->threshold_bytes
.value
;
2949 * Threshold was expressed as a ratio.
2951 * TODO the threshold (in bytes) of conditions expressed
2952 * as a ratio of total buffer size could be cached to
2953 * forego this double-multiplication or it could be performed
2954 * as fixed-point math.
2956 * Note that caching should accomodate the case where the
2957 * condition applies to multiple channels (i.e. don't assume
2958 * that all channels matching my_chann* have the same size...)
2960 threshold
= (uint64_t) (use_condition
->threshold_ratio
.value
*
2961 (double) buffer_capacity
);
2964 condition_type
= lttng_condition_get_type(condition
);
2965 if (condition_type
== LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
) {
2966 DBG("[notification-thread] Low buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
2967 threshold
, sample
->highest_usage
);
2970 * The low condition should only be triggered once _all_ of the
2971 * streams in a channel have gone below the "low" threshold.
2973 if (sample
->highest_usage
<= threshold
) {
2977 DBG("[notification-thread] High buffer usage condition being evaluated: threshold = %" PRIu64
", highest usage = %" PRIu64
,
2978 threshold
, sample
->highest_usage
);
2981 * For high buffer usage scenarios, we want to trigger whenever
2982 * _any_ of the streams has reached the "high" threshold.
2984 if (sample
->highest_usage
>= threshold
) {
2993 bool evaluate_session_consumed_size_condition(
2994 const struct lttng_condition
*condition
,
2995 uint64_t session_consumed_size
)
2998 const struct lttng_condition_session_consumed_size
*size_condition
=
2999 container_of(condition
,
3000 struct lttng_condition_session_consumed_size
,
3003 threshold
= size_condition
->consumed_threshold_bytes
.value
;
3004 DBG("[notification-thread] Session consumed size condition being evaluated: threshold = %" PRIu64
", current size = %" PRIu64
,
3005 threshold
, session_consumed_size
);
3006 return session_consumed_size
>= threshold
;
3010 int evaluate_buffer_condition(const struct lttng_condition
*condition
,
3011 struct lttng_evaluation
**evaluation
,
3012 const struct notification_thread_state
*state
,
3013 const struct channel_state_sample
*previous_sample
,
3014 const struct channel_state_sample
*latest_sample
,
3015 uint64_t previous_session_consumed_total
,
3016 uint64_t latest_session_consumed_total
,
3017 struct channel_info
*channel_info
)
3020 enum lttng_condition_type condition_type
;
3021 const bool previous_sample_available
= !!previous_sample
;
3022 bool previous_sample_result
= false;
3023 bool latest_sample_result
;
3025 condition_type
= lttng_condition_get_type(condition
);
3027 switch (condition_type
) {
3028 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
3029 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
3030 if (caa_likely(previous_sample_available
)) {
3031 previous_sample_result
=
3032 evaluate_buffer_usage_condition(condition
,
3033 previous_sample
, channel_info
->capacity
);
3035 latest_sample_result
= evaluate_buffer_usage_condition(
3036 condition
, latest_sample
,
3037 channel_info
->capacity
);
3039 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
3040 if (caa_likely(previous_sample_available
)) {
3041 previous_sample_result
=
3042 evaluate_session_consumed_size_condition(
3044 previous_session_consumed_total
);
3046 latest_sample_result
=
3047 evaluate_session_consumed_size_condition(
3049 latest_session_consumed_total
);
3052 /* Unknown condition type; internal error. */
3056 if (!latest_sample_result
||
3057 (previous_sample_result
== latest_sample_result
)) {
3059 * Only trigger on a condition evaluation transition.
3061 * NOTE: This edge-triggered logic may not be appropriate for
3062 * future condition types.
3067 if (!evaluation
|| !latest_sample_result
) {
3071 switch (condition_type
) {
3072 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_LOW
:
3073 case LTTNG_CONDITION_TYPE_BUFFER_USAGE_HIGH
:
3074 *evaluation
= lttng_evaluation_buffer_usage_create(
3076 latest_sample
->highest_usage
,
3077 channel_info
->capacity
);
3079 case LTTNG_CONDITION_TYPE_SESSION_CONSUMED_SIZE
:
3080 *evaluation
= lttng_evaluation_session_consumed_size_create(
3081 latest_session_consumed_total
);
3096 int client_enqueue_dropped_notification(struct notification_client
*client
,
3097 struct notification_thread_state
*state
)
3100 struct lttng_notification_channel_message msg
= {
3101 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION_DROPPED
,
3105 ret
= lttng_dynamic_buffer_append(
3106 &client
->communication
.outbound
.buffer
, &msg
,
3112 int send_evaluation_to_clients(const struct lttng_trigger
*trigger
,
3113 const struct lttng_evaluation
*evaluation
,
3114 struct notification_client_list
* client_list
,
3115 struct notification_thread_state
*state
,
3116 uid_t channel_uid
, gid_t channel_gid
)
3119 struct lttng_dynamic_buffer msg_buffer
;
3120 struct notification_client_list_element
*client_list_element
, *tmp
;
3121 const struct lttng_notification notification
= {
3122 .condition
= (struct lttng_condition
*) lttng_trigger_get_const_condition(trigger
),
3123 .evaluation
= (struct lttng_evaluation
*) evaluation
,
3125 struct lttng_notification_channel_message msg_header
= {
3126 .type
= (int8_t) LTTNG_NOTIFICATION_CHANNEL_MESSAGE_TYPE_NOTIFICATION
,
3129 lttng_dynamic_buffer_init(&msg_buffer
);
3131 ret
= lttng_dynamic_buffer_append(&msg_buffer
, &msg_header
,
3132 sizeof(msg_header
));
3137 ret
= lttng_notification_serialize(¬ification
, &msg_buffer
);
3139 ERR("[notification-thread] Failed to serialize notification");
3144 /* Update payload size. */
3145 ((struct lttng_notification_channel_message
* ) msg_buffer
.data
)->size
=
3146 (uint32_t) (msg_buffer
.size
- sizeof(msg_header
));
3148 cds_list_for_each_entry_safe(client_list_element
, tmp
,
3149 &client_list
->list
, node
) {
3150 struct notification_client
*client
=
3151 client_list_element
->client
;
3153 if (client
->uid
!= channel_uid
&& client
->gid
!= channel_gid
&&
3155 /* Client is not allowed to monitor this channel. */
3156 DBG("[notification-thread] Skipping client at it does not have the permission to receive notification for this channel");
3160 DBG("[notification-thread] Sending notification to client (fd = %i, %zu bytes)",
3161 client
->socket
, msg_buffer
.size
);
3162 if (client
->communication
.outbound
.buffer
.size
) {
3164 * Outgoing data is already buffered for this client;
3165 * drop the notification and enqueue a "dropped
3166 * notification" message if this is the first dropped
3167 * notification since the socket spilled-over to the
3170 DBG("[notification-thread] Dropping notification addressed to client (socket fd = %i)",
3172 if (!client
->communication
.outbound
.dropped_notification
) {
3173 client
->communication
.outbound
.dropped_notification
= true;
3174 ret
= client_enqueue_dropped_notification(
3183 ret
= lttng_dynamic_buffer_append_buffer(
3184 &client
->communication
.outbound
.buffer
,
3190 ret
= client_flush_outgoing_queue(client
, state
);
3197 lttng_dynamic_buffer_reset(&msg_buffer
);
3201 int handle_notification_thread_channel_sample(
3202 struct notification_thread_state
*state
, int pipe
,
3203 enum lttng_domain_type domain
)
3206 struct lttcomm_consumer_channel_monitor_msg sample_msg
;
3207 struct channel_info
*channel_info
;
3208 struct cds_lfht_node
*node
;
3209 struct cds_lfht_iter iter
;
3210 struct lttng_channel_trigger_list
*trigger_list
;
3211 struct lttng_trigger_list_element
*trigger_list_element
;
3212 bool previous_sample_available
= false;
3213 struct channel_state_sample previous_sample
, latest_sample
;
3214 uint64_t previous_session_consumed_total
, latest_session_consumed_total
;
3217 * The monitoring pipe only holds messages smaller than PIPE_BUF,
3218 * ensuring that read/write of sampling messages are atomic.
3220 ret
= lttng_read(pipe
, &sample_msg
, sizeof(sample_msg
));
3221 if (ret
!= sizeof(sample_msg
)) {
3222 ERR("[notification-thread] Failed to read from monitoring pipe (fd = %i)",
3229 latest_sample
.key
.key
= sample_msg
.key
;
3230 latest_sample
.key
.domain
= domain
;
3231 latest_sample
.highest_usage
= sample_msg
.highest
;
3232 latest_sample
.lowest_usage
= sample_msg
.lowest
;
3233 latest_sample
.channel_total_consumed
= sample_msg
.total_consumed
;
3237 /* Retrieve the channel's informations */
3238 cds_lfht_lookup(state
->channels_ht
,
3239 hash_channel_key(&latest_sample
.key
),
3243 node
= cds_lfht_iter_get_node(&iter
);
3244 if (caa_unlikely(!node
)) {
3246 * Not an error since the consumer can push a sample to the pipe
3247 * and the rest of the session daemon could notify us of the
3248 * channel's destruction before we get a chance to process that
3251 DBG("[notification-thread] Received a sample for an unknown channel from consumerd, key = %" PRIu64
" in %s domain",
3252 latest_sample
.key
.key
,
3253 domain
== LTTNG_DOMAIN_KERNEL
? "kernel" :
3257 channel_info
= caa_container_of(node
, struct channel_info
,
3259 DBG("[notification-thread] Handling channel sample for channel %s (key = %" PRIu64
") in session %s (highest usage = %" PRIu64
", lowest usage = %" PRIu64
", total consumed = %" PRIu64
")",
3261 latest_sample
.key
.key
,
3262 channel_info
->session_info
->name
,
3263 latest_sample
.highest_usage
,
3264 latest_sample
.lowest_usage
,
3265 latest_sample
.channel_total_consumed
);
3267 previous_session_consumed_total
=
3268 channel_info
->session_info
->consumed_data_size
;
3270 /* Retrieve the channel's last sample, if it exists, and update it. */
3271 cds_lfht_lookup(state
->channel_state_ht
,
3272 hash_channel_key(&latest_sample
.key
),
3273 match_channel_state_sample
,
3276 node
= cds_lfht_iter_get_node(&iter
);
3277 if (caa_likely(node
)) {
3278 struct channel_state_sample
*stored_sample
;
3280 /* Update the sample stored. */
3281 stored_sample
= caa_container_of(node
,
3282 struct channel_state_sample
,
3283 channel_state_ht_node
);
3285 memcpy(&previous_sample
, stored_sample
,
3286 sizeof(previous_sample
));
3287 stored_sample
->highest_usage
= latest_sample
.highest_usage
;
3288 stored_sample
->lowest_usage
= latest_sample
.lowest_usage
;
3289 stored_sample
->channel_total_consumed
= latest_sample
.channel_total_consumed
;
3290 previous_sample_available
= true;
3292 latest_session_consumed_total
=
3293 previous_session_consumed_total
+
3294 (latest_sample
.channel_total_consumed
- previous_sample
.channel_total_consumed
);
3297 * This is the channel's first sample, allocate space for and
3298 * store the new sample.
3300 struct channel_state_sample
*stored_sample
;
3302 stored_sample
= zmalloc(sizeof(*stored_sample
));
3303 if (!stored_sample
) {
3308 memcpy(stored_sample
, &latest_sample
, sizeof(*stored_sample
));
3309 cds_lfht_node_init(&stored_sample
->channel_state_ht_node
);
3310 cds_lfht_add(state
->channel_state_ht
,
3311 hash_channel_key(&stored_sample
->key
),
3312 &stored_sample
->channel_state_ht_node
);
3314 latest_session_consumed_total
=
3315 previous_session_consumed_total
+
3316 latest_sample
.channel_total_consumed
;
3319 channel_info
->session_info
->consumed_data_size
=
3320 latest_session_consumed_total
;
3322 /* Find triggers associated with this channel. */
3323 cds_lfht_lookup(state
->channel_triggers_ht
,
3324 hash_channel_key(&latest_sample
.key
),
3325 match_channel_trigger_list
,
3328 node
= cds_lfht_iter_get_node(&iter
);
3329 if (caa_likely(!node
)) {
3333 trigger_list
= caa_container_of(node
, struct lttng_channel_trigger_list
,
3334 channel_triggers_ht_node
);
3335 cds_list_for_each_entry(trigger_list_element
, &trigger_list
->list
,
3337 const struct lttng_condition
*condition
;
3338 const struct lttng_action
*action
;
3339 const struct lttng_trigger
*trigger
;
3340 struct notification_client_list
*client_list
;
3341 struct lttng_evaluation
*evaluation
= NULL
;
3343 trigger
= trigger_list_element
->trigger
;
3344 condition
= lttng_trigger_get_const_condition(trigger
);
3346 action
= lttng_trigger_get_const_action(trigger
);
3348 /* Notify actions are the only type currently supported. */
3349 assert(lttng_action_get_type_const(action
) ==
3350 LTTNG_ACTION_TYPE_NOTIFY
);
3353 * Check if any client is subscribed to the result of this
3356 client_list
= get_client_list_from_condition(state
, condition
);
3357 assert(client_list
);
3358 if (cds_list_empty(&client_list
->list
)) {
3360 * No clients interested in the evaluation's result,
3366 ret
= evaluate_buffer_condition(condition
, &evaluation
, state
,
3367 previous_sample_available
? &previous_sample
: NULL
,
3369 previous_session_consumed_total
,
3370 latest_session_consumed_total
,
3372 if (caa_unlikely(ret
)) {
3376 if (caa_likely(!evaluation
)) {
3380 /* Dispatch evaluation result to all clients. */
3381 ret
= send_evaluation_to_clients(trigger_list_element
->trigger
,
3382 evaluation
, client_list
, state
,
3383 channel_info
->session_info
->uid
,
3384 channel_info
->session_info
->gid
);
3385 lttng_evaluation_destroy(evaluation
);
3386 if (caa_unlikely(ret
)) {