2 * Copyright (C) 2013 - David Goulet <dgoulet@efficios.com>
3 * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License, version 2 only, as
7 * published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc., 51
16 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 #include <urcu/uatomic.h>
22 #include <urcu/rculist.h>
24 #include <common/common.h>
25 #include <common/sessiond-comm/agent.h>
27 #include <common/compat/endian.h>
34 #define AGENT_RET_CODE_INDEX(code) (code - AGENT_RET_CODE_SUCCESS)
37 * Agent application context representation.
39 struct agent_app_ctx
{
43 /* agent_app_ctx are part of the agent app_ctx_list. */
44 struct cds_list_head list_node
;
46 /* For call_rcu teardown. */
47 struct rcu_head rcu_node
;
51 * Human readable agent return code.
53 static const char *error_string_array
[] = {
54 [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_SUCCESS
) ] = "Success",
55 [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_INVALID
) ] = "Invalid command",
56 [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_UNKNOWN_NAME
) ] = "Unknown logger name",
59 [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_NR
) ] = "Unknown code",
63 void log_reply_code(uint32_t in_reply_ret_code
)
65 int level
= PRINT_DBG3
;
67 * reply_ret_code and in_reply_ret_code are kept separate to have a
68 * sanitized value (used to retrieve the human readable string) and the
69 * original value which is logged as-is.
71 uint32_t reply_ret_code
= in_reply_ret_code
;
73 if (reply_ret_code
< AGENT_RET_CODE_SUCCESS
||
74 reply_ret_code
>= AGENT_RET_CODE_NR
) {
75 reply_ret_code
= AGENT_RET_CODE_NR
;
79 LOG(level
, "Agent replied with retcode: %s (%"PRIu32
")",
80 error_string_array
[AGENT_RET_CODE_INDEX(
86 * Match function for the events hash table lookup by name.
88 static int ht_match_event_by_name(struct cds_lfht_node
*node
,
91 struct agent_event
*event
;
92 const struct agent_ht_key
*key
;
97 event
= caa_container_of(node
, struct agent_event
, node
.node
);
100 /* Match 1 elements of the key: name. */
103 if (strncmp(event
->name
, key
->name
, sizeof(event
->name
)) != 0) {
114 * Match function for the events hash table lookup by name and loglevel.
116 static int ht_match_event(struct cds_lfht_node
*node
,
119 struct agent_event
*event
;
120 const struct agent_ht_key
*key
;
126 event
= caa_container_of(node
, struct agent_event
, node
.node
);
129 /* Match 2 elements of the key: name and loglevel. */
132 if (strncmp(event
->name
, key
->name
, sizeof(event
->name
)) != 0) {
136 /* Event loglevel value and type. */
137 ll_match
= loglevels_match(event
->loglevel_type
,
138 event
->loglevel_value
, key
->loglevel_type
,
139 key
->loglevel_value
, LTTNG_EVENT_LOGLEVEL_ALL
);
145 /* Filter expression */
146 if (strncmp(event
->filter_expression
, key
->filter_expression
,
147 strlen(event
->filter_expression
)) != 0) {
158 * Add unique agent event based on the event name and loglevel.
160 static void add_unique_agent_event(struct lttng_ht
*ht
,
161 struct agent_event
*event
)
163 struct cds_lfht_node
*node_ptr
;
164 struct agent_ht_key key
;
170 key
.name
= event
->name
;
171 key
.loglevel_value
= event
->loglevel_value
;
172 key
.loglevel_type
= event
->loglevel_type
;
173 key
.filter_expression
= event
->filter_expression
;
175 node_ptr
= cds_lfht_add_unique(ht
->ht
,
176 ht
->hash_fct(event
->node
.key
, lttng_ht_seed
),
177 ht_match_event
, &key
, &event
->node
.node
);
178 assert(node_ptr
== &event
->node
.node
);
182 * URCU delayed agent event reclaim.
184 static void destroy_event_agent_rcu(struct rcu_head
*head
)
186 struct lttng_ht_node_str
*node
=
187 caa_container_of(head
, struct lttng_ht_node_str
, head
);
188 struct agent_event
*event
=
189 caa_container_of(node
, struct agent_event
, node
);
191 agent_destroy_event(event
);
195 * URCU delayed agent app reclaim.
197 static void destroy_app_agent_rcu(struct rcu_head
*head
)
199 struct lttng_ht_node_ulong
*node
=
200 caa_container_of(head
, struct lttng_ht_node_ulong
, head
);
201 struct agent_app
*app
=
202 caa_container_of(node
, struct agent_app
, node
);
208 * Communication with the agent. Send the message header to the given socket in
211 * Return 0 on success or else a negative errno message of sendmsg() op.
213 static int send_header(struct lttcomm_sock
*sock
, uint64_t data_size
,
214 uint32_t cmd
, uint32_t cmd_version
)
218 struct lttcomm_agent_hdr msg
;
222 memset(&msg
, 0, sizeof(msg
));
223 msg
.data_size
= htobe64(data_size
);
224 msg
.cmd
= htobe32(cmd
);
225 msg
.cmd_version
= htobe32(cmd_version
);
227 size
= sock
->ops
->sendmsg(sock
, &msg
, sizeof(msg
), 0);
228 if (size
< sizeof(msg
)) {
239 * Communication call with the agent. Send the payload to the given socket. The
240 * header MUST be sent prior to this call.
242 * Return 0 on success or else a negative errno value of sendmsg() op.
244 static int send_payload(struct lttcomm_sock
*sock
, const void *data
,
253 len
= sock
->ops
->sendmsg(sock
, data
, size
, 0);
265 * Communication call with the agent. Receive reply from the agent using the
268 * Return 0 on success or else a negative errno value from recvmsg() op.
270 static int recv_reply(struct lttcomm_sock
*sock
, void *buf
, size_t size
)
278 len
= sock
->ops
->recvmsg(sock
, buf
, size
, 0);
290 * Internal event listing for a given app. Populate events.
292 * Return number of element in the list or else a negative LTTNG_ERR* code.
293 * On success, the caller is responsible for freeing the memory
294 * allocated for "events".
296 static ssize_t
list_events(struct agent_app
*app
, struct lttng_event
**events
)
298 int ret
, i
, len
= 0, offset
= 0;
301 uint32_t reply_ret_code
;
302 struct lttng_event
*tmp_events
= NULL
;
303 struct lttcomm_agent_list_reply
*reply
= NULL
;
304 struct lttcomm_agent_list_reply_hdr reply_hdr
;
310 DBG2("Agent listing events for app pid: %d and socket %d", app
->pid
,
313 ret
= send_header(app
->sock
, 0, AGENT_CMD_LIST
, 0);
318 /* Get list header so we know how much we'll receive. */
319 ret
= recv_reply(app
->sock
, &reply_hdr
, sizeof(reply_hdr
));
324 reply_ret_code
= be32toh(reply_hdr
.ret_code
);
325 log_reply_code(reply_ret_code
);
326 switch (reply_ret_code
) {
327 case AGENT_RET_CODE_SUCCESS
:
328 data_size
= be32toh(reply_hdr
.data_size
) + sizeof(*reply
);
335 reply
= zmalloc(data_size
);
337 ret
= LTTNG_ERR_NOMEM
;
341 /* Get the list with the appropriate data size. */
342 ret
= recv_reply(app
->sock
, reply
, data_size
);
347 nb_event
= be32toh(reply
->nb_event
);
348 tmp_events
= zmalloc(sizeof(*tmp_events
) * nb_event
);
350 ret
= LTTNG_ERR_NOMEM
;
354 for (i
= 0; i
< nb_event
; i
++) {
356 strncpy(tmp_events
[i
].name
, reply
->payload
+ offset
,
357 sizeof(tmp_events
[i
].name
));
358 tmp_events
[i
].pid
= app
->pid
;
359 tmp_events
[i
].enabled
= -1;
360 len
= strlen(reply
->payload
+ offset
) + 1;
363 *events
= tmp_events
;
369 ret
= LTTNG_ERR_UST_LIST_FAIL
;
378 * Internal enable agent event on a agent application. This function
379 * communicates with the agent to enable a given event.
381 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
383 static int enable_event(struct agent_app
*app
, struct agent_event
*event
)
388 size_t filter_expression_length
;
389 uint32_t reply_ret_code
;
390 struct lttcomm_agent_enable_event msg
;
391 struct lttcomm_agent_generic_reply reply
;
397 DBG2("Agent enabling event %s for app pid: %d and socket %d", event
->name
,
398 app
->pid
, app
->sock
->fd
);
401 * Calculate the payload's size, which is the fixed-size struct followed
402 * by the variable-length filter expression (+1 for the ending \0).
404 if (!event
->filter_expression
) {
405 filter_expression_length
= 0;
407 filter_expression_length
= strlen(event
->filter_expression
) + 1;
409 data_size
= sizeof(msg
) + filter_expression_length
;
411 memset(&msg
, 0, sizeof(msg
));
412 msg
.loglevel_value
= htobe32(event
->loglevel_value
);
413 msg
.loglevel_type
= htobe32(event
->loglevel_type
);
414 if (lttng_strncpy(msg
.name
, event
->name
, sizeof(msg
.name
))) {
415 ret
= LTTNG_ERR_INVALID
;
418 msg
.filter_expression_length
= htobe32(filter_expression_length
);
420 ret
= send_header(app
->sock
, data_size
, AGENT_CMD_ENABLE
, 0);
425 bytes_to_send
= zmalloc(data_size
);
426 if (!bytes_to_send
) {
427 ret
= LTTNG_ERR_NOMEM
;
431 memcpy(bytes_to_send
, &msg
, sizeof(msg
));
432 if (filter_expression_length
> 0) {
433 memcpy(bytes_to_send
+ sizeof(msg
), event
->filter_expression
,
434 filter_expression_length
);
437 ret
= send_payload(app
->sock
, bytes_to_send
, data_size
);
443 ret
= recv_reply(app
->sock
, &reply
, sizeof(reply
));
448 reply_ret_code
= be32toh(reply
.ret_code
);
449 log_reply_code(reply_ret_code
);
450 switch (reply_ret_code
) {
451 case AGENT_RET_CODE_SUCCESS
:
453 case AGENT_RET_CODE_UNKNOWN_NAME
:
454 ret
= LTTNG_ERR_UST_EVENT_NOT_FOUND
;
464 ret
= LTTNG_ERR_UST_ENABLE_FAIL
;
470 * Send Pascal-style string. Size is sent as a 32-bit big endian integer.
473 int send_pstring(struct lttcomm_sock
*sock
, const char *str
, uint32_t len
)
478 len_be
= htobe32(len
);
479 ret
= send_payload(sock
, &len_be
, sizeof(len_be
));
484 ret
= send_payload(sock
, str
, len
);
493 * Internal enable application context on an agent application. This function
494 * communicates with the agent to enable a given application context.
496 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
498 static int app_context_op(struct agent_app
*app
,
499 struct agent_app_ctx
*ctx
, enum lttcomm_agent_command cmd
)
502 uint32_t reply_ret_code
;
503 struct lttcomm_agent_generic_reply reply
;
504 size_t app_ctx_provider_name_len
, app_ctx_name_len
, data_size
;
509 assert(cmd
== AGENT_CMD_APP_CTX_ENABLE
||
510 cmd
== AGENT_CMD_APP_CTX_DISABLE
);
512 DBG2("Agent %s application %s:%s for app pid: %d and socket %d",
513 cmd
== AGENT_CMD_APP_CTX_ENABLE
? "enabling" : "disabling",
514 ctx
->provider_name
, ctx
->ctx_name
,
515 app
->pid
, app
->sock
->fd
);
518 * Calculate the payload's size, which consists of the size (u32, BE)
519 * of the provider name, the NULL-terminated provider name string, the
520 * size (u32, BE) of the context name, followed by the NULL-terminated
521 * context name string.
523 app_ctx_provider_name_len
= strlen(ctx
->provider_name
) + 1;
524 app_ctx_name_len
= strlen(ctx
->ctx_name
) + 1;
525 data_size
= sizeof(uint32_t) + app_ctx_provider_name_len
+
526 sizeof(uint32_t) + app_ctx_name_len
;
528 ret
= send_header(app
->sock
, data_size
, cmd
, 0);
533 if (app_ctx_provider_name_len
> UINT32_MAX
||
534 app_ctx_name_len
> UINT32_MAX
) {
535 ERR("Application context name > MAX_UINT32");
536 ret
= LTTNG_ERR_INVALID
;
540 ret
= send_pstring(app
->sock
, ctx
->provider_name
,
541 (uint32_t) app_ctx_provider_name_len
);
546 ret
= send_pstring(app
->sock
, ctx
->ctx_name
,
547 (uint32_t) app_ctx_name_len
);
552 ret
= recv_reply(app
->sock
, &reply
, sizeof(reply
));
557 reply_ret_code
= be32toh(reply
.ret_code
);
558 log_reply_code(reply_ret_code
);
559 switch (reply_ret_code
) {
560 case AGENT_RET_CODE_SUCCESS
:
570 ret
= LTTNG_ERR_UST_ENABLE_FAIL
;
576 * Internal disable agent event call on a agent application. This function
577 * communicates with the agent to disable a given event.
579 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
581 static int disable_event(struct agent_app
*app
, struct agent_event
*event
)
585 uint32_t reply_ret_code
;
586 struct lttcomm_agent_disable_event msg
;
587 struct lttcomm_agent_generic_reply reply
;
593 DBG2("Agent disabling event %s for app pid: %d and socket %d", event
->name
,
594 app
->pid
, app
->sock
->fd
);
596 data_size
= sizeof(msg
);
598 ret
= send_header(app
->sock
, data_size
, AGENT_CMD_DISABLE
, 0);
603 memset(&msg
, 0, sizeof(msg
));
604 strncpy(msg
.name
, event
->name
, sizeof(msg
.name
));
605 ret
= send_payload(app
->sock
, &msg
, sizeof(msg
));
610 ret
= recv_reply(app
->sock
, &reply
, sizeof(reply
));
615 reply_ret_code
= be32toh(reply
.ret_code
);
616 log_reply_code(reply_ret_code
);
617 switch (reply_ret_code
) {
618 case AGENT_RET_CODE_SUCCESS
:
620 case AGENT_RET_CODE_UNKNOWN_NAME
:
621 ret
= LTTNG_ERR_UST_EVENT_NOT_FOUND
;
631 ret
= LTTNG_ERR_UST_DISABLE_FAIL
;
637 * Send back the registration DONE command to a given agent application.
639 * Return 0 on success or else a negative value.
641 int agent_send_registration_done(struct agent_app
*app
)
646 DBG("Agent sending registration done to app socket %d", app
->sock
->fd
);
648 return send_header(app
->sock
, 0, AGENT_CMD_REG_DONE
, 0);
652 * Enable agent event on every agent applications registered with the session
655 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
657 int agent_enable_event(struct agent_event
*event
,
658 enum lttng_domain_type domain
)
661 struct agent_app
*app
;
662 struct lttng_ht_iter iter
;
668 cds_lfht_for_each_entry(agent_apps_ht_by_sock
->ht
, &iter
.iter
, app
,
670 if (app
->domain
!= domain
) {
674 /* Enable event on agent application through TCP socket. */
675 ret
= enable_event(app
, event
);
676 if (ret
!= LTTNG_OK
) {
690 void destroy_app_ctx(struct agent_app_ctx
*ctx
)
692 free(ctx
->provider_name
);
698 struct agent_app_ctx
*create_app_ctx(struct lttng_event_context
*ctx
)
700 struct agent_app_ctx
*agent_ctx
= NULL
;
706 assert(ctx
->ctx
== LTTNG_EVENT_CONTEXT_APP_CONTEXT
);
707 agent_ctx
= zmalloc(sizeof(*ctx
));
712 agent_ctx
->provider_name
= strdup(ctx
->u
.app_ctx
.provider_name
);
713 agent_ctx
->ctx_name
= strdup(ctx
->u
.app_ctx
.ctx_name
);
714 if (!agent_ctx
->provider_name
|| !agent_ctx
->ctx_name
) {
715 destroy_app_ctx(agent_ctx
);
723 * Enable agent context on every agent applications registered with the session
726 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
728 int agent_enable_context(struct lttng_event_context
*ctx
,
729 enum lttng_domain_type domain
)
732 struct agent_app
*app
;
733 struct lttng_ht_iter iter
;
736 if (ctx
->ctx
!= LTTNG_EVENT_CONTEXT_APP_CONTEXT
) {
737 ret
= LTTNG_ERR_INVALID
;
743 cds_lfht_for_each_entry(agent_apps_ht_by_sock
->ht
, &iter
.iter
, app
,
745 struct agent_app_ctx
*agent_ctx
;
747 if (app
->domain
!= domain
) {
751 agent_ctx
= create_app_ctx(ctx
);
753 ret
= LTTNG_ERR_NOMEM
;
757 /* Enable event on agent application through TCP socket. */
758 ret
= app_context_op(app
, agent_ctx
, AGENT_CMD_APP_CTX_ENABLE
);
759 destroy_app_ctx(agent_ctx
);
760 if (ret
!= LTTNG_OK
) {
774 * Disable agent event on every agent application registered with the session
777 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
779 int agent_disable_event(struct agent_event
*event
,
780 enum lttng_domain_type domain
)
783 struct agent_app
*app
;
784 struct lttng_ht_iter iter
;
787 if (!event
->enabled
) {
793 cds_lfht_for_each_entry(agent_apps_ht_by_sock
->ht
, &iter
.iter
, app
,
795 if (app
->domain
!= domain
) {
799 /* Enable event on agent application through TCP socket. */
800 ret
= disable_event(app
, event
);
801 if (ret
!= LTTNG_OK
) {
815 * Disable agent context on every agent application registered with the session
818 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
820 int disable_context(struct agent_app_ctx
*ctx
, enum lttng_domain_type domain
)
823 struct agent_app
*app
;
824 struct lttng_ht_iter iter
;
829 DBG2("Disabling agent application context %s:%s",
830 ctx
->provider_name
, ctx
->ctx_name
);
831 cds_lfht_for_each_entry(agent_apps_ht_by_sock
->ht
, &iter
.iter
, app
,
833 if (app
->domain
!= domain
) {
837 ret
= app_context_op(app
, ctx
, AGENT_CMD_APP_CTX_DISABLE
);
838 if (ret
!= LTTNG_OK
) {
848 * Ask every agent for the list of possible event. Events is allocated with the
849 * events of every agent application.
851 * Return the number of events or else a negative value.
853 int agent_list_events(struct lttng_event
**events
,
854 enum lttng_domain_type domain
)
857 size_t nbmem
, count
= 0;
858 struct agent_app
*app
;
859 struct lttng_event
*tmp_events
= NULL
;
860 struct lttng_ht_iter iter
;
864 DBG2("Agent listing events for domain %d", domain
);
866 nbmem
= UST_APP_EVENT_LIST_SIZE
;
867 tmp_events
= zmalloc(nbmem
* sizeof(*tmp_events
));
869 PERROR("zmalloc agent list events");
875 cds_lfht_for_each_entry(agent_apps_ht_by_sock
->ht
, &iter
.iter
, app
,
878 struct lttng_event
*agent_events
;
880 /* Skip domain not asked by the list. */
881 if (app
->domain
!= domain
) {
885 nb_ev
= list_events(app
, &agent_events
);
891 if (count
+ nb_ev
> nbmem
) {
892 /* In case the realloc fails, we free the memory */
893 struct lttng_event
*new_tmp_events
;
896 new_nbmem
= max_t(size_t, count
+ nb_ev
, nbmem
<< 1);
897 DBG2("Reallocating agent event list from %zu to %zu entries",
899 new_tmp_events
= realloc(tmp_events
,
900 new_nbmem
* sizeof(*new_tmp_events
));
901 if (!new_tmp_events
) {
902 PERROR("realloc agent events");
907 /* Zero the new memory */
908 memset(new_tmp_events
+ nbmem
, 0,
909 (new_nbmem
- nbmem
) * sizeof(*new_tmp_events
));
911 tmp_events
= new_tmp_events
;
913 memcpy(tmp_events
+ count
, agent_events
,
914 nb_ev
* sizeof(*tmp_events
));
921 *events
= tmp_events
;
932 * Create a agent app object using the given PID.
934 * Return newly allocated object or else NULL on error.
936 struct agent_app
*agent_create_app(pid_t pid
, enum lttng_domain_type domain
,
937 struct lttcomm_sock
*sock
)
939 struct agent_app
*app
;
943 app
= zmalloc(sizeof(*app
));
945 PERROR("zmalloc agent create");
950 app
->domain
= domain
;
952 lttng_ht_node_init_ulong(&app
->node
, (unsigned long) app
->sock
->fd
);
959 * Lookup agent app by socket in the global hash table.
961 * RCU read side lock MUST be acquired.
963 * Return object if found else NULL.
965 struct agent_app
*agent_find_app_by_sock(int sock
)
967 struct lttng_ht_node_ulong
*node
;
968 struct lttng_ht_iter iter
;
969 struct agent_app
*app
;
973 lttng_ht_lookup(agent_apps_ht_by_sock
, (void *)((unsigned long) sock
), &iter
);
974 node
= lttng_ht_iter_get_node_ulong(&iter
);
978 app
= caa_container_of(node
, struct agent_app
, node
);
980 DBG3("Agent app pid %d found by sock %d.", app
->pid
, sock
);
984 DBG3("Agent app NOT found by sock %d.", sock
);
989 * Add agent application object to the global hash table.
991 void agent_add_app(struct agent_app
*app
)
995 DBG3("Agent adding app sock: %d and pid: %d to ht", app
->sock
->fd
, app
->pid
);
996 lttng_ht_add_unique_ulong(agent_apps_ht_by_sock
, &app
->node
);
1000 * Delete agent application from the global hash table.
1002 * rcu_read_lock() must be held by the caller.
1004 void agent_delete_app(struct agent_app
*app
)
1007 struct lttng_ht_iter iter
;
1011 DBG3("Agent deleting app pid: %d and sock: %d", app
->pid
, app
->sock
->fd
);
1013 iter
.iter
.node
= &app
->node
.node
;
1014 ret
= lttng_ht_del(agent_apps_ht_by_sock
, &iter
);
1019 * Destroy an agent application object by detaching it from its corresponding
1020 * UST app if one is connected by closing the socket. Finally, perform a
1021 * delayed memory reclaim.
1023 void agent_destroy_app(struct agent_app
*app
)
1028 app
->sock
->ops
->close(app
->sock
);
1029 lttcomm_destroy_sock(app
->sock
);
1032 call_rcu(&app
->node
.head
, destroy_app_agent_rcu
);
1036 * Initialize an already allocated agent object.
1038 * Return 0 on success or else a negative errno value.
1040 int agent_init(struct agent
*agt
)
1046 agt
->events
= lttng_ht_new(0, LTTNG_HT_TYPE_STRING
);
1051 lttng_ht_node_init_u64(&agt
->node
, agt
->domain
);
1053 CDS_INIT_LIST_HEAD(&agt
->app_ctx_list
);
1061 * Add agent object to the given hash table.
1063 void agent_add(struct agent
*agt
, struct lttng_ht
*ht
)
1068 DBG3("Agent adding from domain %d", agt
->domain
);
1070 lttng_ht_add_unique_u64(ht
, &agt
->node
);
1074 * Create an agent object for the given domain.
1076 * Return the allocated agent or NULL on error.
1078 struct agent
*agent_create(enum lttng_domain_type domain
)
1083 agt
= zmalloc(sizeof(struct agent
));
1087 agt
->domain
= domain
;
1089 ret
= agent_init(agt
);
1101 * Create a newly allocated agent event data structure.
1102 * Ownership of filter_expression is taken.
1104 * Return a new object else NULL on error.
1106 struct agent_event
*agent_create_event(const char *name
,
1107 enum lttng_loglevel_type loglevel_type
, int loglevel_value
,
1108 struct lttng_filter_bytecode
*filter
, char *filter_expression
)
1110 struct agent_event
*event
= NULL
;
1112 DBG3("Agent create new event with name %s, loglevel type %d, \
1113 loglevel value %d and filter %s",
1114 name
, loglevel_type
, loglevel_value
,
1115 filter_expression
? filter_expression
: "NULL");
1118 ERR("Failed to create agent event; no name provided.");
1122 event
= zmalloc(sizeof(*event
));
1127 strncpy(event
->name
, name
, sizeof(event
->name
));
1128 event
->name
[sizeof(event
->name
) - 1] = '\0';
1129 lttng_ht_node_init_str(&event
->node
, event
->name
);
1131 event
->loglevel_value
= loglevel_value
;
1132 event
->loglevel_type
= loglevel_type
;
1133 event
->filter
= filter
;
1134 event
->filter_expression
= filter_expression
;
1140 * Unique add of a agent event to an agent object.
1142 void agent_add_event(struct agent_event
*event
, struct agent
*agt
)
1146 assert(agt
->events
);
1148 DBG3("Agent adding event %s", event
->name
);
1149 add_unique_agent_event(agt
->events
, event
);
1150 agt
->being_used
= 1;
1154 * Unique add of a agent context to an agent object.
1156 int agent_add_context(struct lttng_event_context
*ctx
, struct agent
*agt
)
1159 struct agent_app_ctx
*agent_ctx
= NULL
;
1163 assert(agt
->events
);
1164 assert(ctx
->ctx
== LTTNG_EVENT_CONTEXT_APP_CONTEXT
);
1166 agent_ctx
= create_app_ctx(ctx
);
1168 ret
= LTTNG_ERR_NOMEM
;
1172 DBG3("Agent adding context %s:%s", ctx
->u
.app_ctx
.provider_name
,
1173 ctx
->u
.app_ctx
.ctx_name
);
1174 cds_list_add_tail_rcu(&agent_ctx
->list_node
, &agt
->app_ctx_list
);
1180 * Find multiple agent events sharing the given name.
1182 * RCU read side lock MUST be acquired. It must be held for the
1183 * duration of the iteration.
1185 * Sets the given iterator.
1187 void agent_find_events_by_name(const char *name
, struct agent
*agt
,
1188 struct lttng_ht_iter
* iter
)
1190 struct lttng_ht
*ht
;
1191 struct agent_ht_key key
;
1195 assert(agt
->events
);
1201 cds_lfht_lookup(ht
->ht
, ht
->hash_fct((void *) name
, lttng_ht_seed
),
1202 ht_match_event_by_name
, &key
, &iter
->iter
);
1206 * Get the next agent event duplicate by name. This should be called
1207 * after a call to agent_find_events_by_name() to iterate on events.
1209 * The RCU read lock must be held during the iteration and for as long
1210 * as the object the iterator points to remains in use.
1212 void agent_event_next_duplicate(const char *name
,
1213 struct agent
*agt
, struct lttng_ht_iter
* iter
)
1215 struct agent_ht_key key
;
1219 cds_lfht_next_duplicate(agt
->events
->ht
, ht_match_event_by_name
,
1224 * Find a agent event in the given agent using name, loglevel and filter.
1226 * RCU read side lock MUST be acquired. It must be kept for as long as
1227 * the returned agent_event is used.
1229 * Return object if found else NULL.
1231 struct agent_event
*agent_find_event(const char *name
,
1232 enum lttng_loglevel_type loglevel_type
, int loglevel_value
,
1233 char *filter_expression
, struct agent
*agt
)
1235 struct lttng_ht_node_str
*node
;
1236 struct lttng_ht_iter iter
;
1237 struct lttng_ht
*ht
;
1238 struct agent_ht_key key
;
1242 assert(agt
->events
);
1246 key
.loglevel_value
= loglevel_value
;
1247 key
.loglevel_type
= loglevel_type
;
1248 key
.filter_expression
= filter_expression
;
1250 cds_lfht_lookup(ht
->ht
, ht
->hash_fct((void *) name
, lttng_ht_seed
),
1251 ht_match_event
, &key
, &iter
.iter
);
1252 node
= lttng_ht_iter_get_node_str(&iter
);
1257 DBG3("Agent event found %s.", name
);
1258 return caa_container_of(node
, struct agent_event
, node
);
1261 DBG3("Agent event NOT found %s.", name
);
1266 * Free given agent event. This event must not be globally visible at this
1267 * point (only expected to be used on failure just after event creation). After
1268 * this call, the pointer is not usable anymore.
1270 void agent_destroy_event(struct agent_event
*event
)
1274 free(event
->filter
);
1275 free(event
->filter_expression
);
1276 free(event
->exclusion
);
1281 void destroy_app_ctx_rcu(struct rcu_head
*head
)
1283 struct agent_app_ctx
*ctx
=
1284 caa_container_of(head
, struct agent_app_ctx
, rcu_node
);
1286 destroy_app_ctx(ctx
);
1290 * Destroy an agent completely.
1292 void agent_destroy(struct agent
*agt
)
1294 struct lttng_ht_node_str
*node
;
1295 struct lttng_ht_iter iter
;
1296 struct agent_app_ctx
*ctx
;
1300 DBG3("Agent destroy");
1303 cds_lfht_for_each_entry(agt
->events
->ht
, &iter
.iter
, node
, node
) {
1305 struct agent_event
*event
;
1308 * When destroying an event, we have to try to disable it on the
1309 * agent side so the event stops generating data. The return
1310 * value is not important since we have to continue anyway
1311 * destroying the object.
1313 event
= caa_container_of(node
, struct agent_event
, node
);
1314 (void) agent_disable_event(event
, agt
->domain
);
1316 ret
= lttng_ht_del(agt
->events
, &iter
);
1318 call_rcu(&node
->head
, destroy_event_agent_rcu
);
1321 cds_list_for_each_entry_rcu(ctx
, &agt
->app_ctx_list
, list_node
) {
1322 (void) disable_context(ctx
, agt
->domain
);
1323 cds_list_del(&ctx
->list_node
);
1324 call_rcu(&ctx
->rcu_node
, destroy_app_ctx_rcu
);
1327 ht_cleanup_push(agt
->events
);
1332 * Allocate agent_apps_ht_by_sock.
1334 int agent_app_ht_alloc(void)
1338 agent_apps_ht_by_sock
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
1339 if (!agent_apps_ht_by_sock
) {
1347 * Destroy a agent application by socket.
1349 void agent_destroy_app_by_sock(int sock
)
1351 struct agent_app
*app
;
1356 * Not finding an application is a very important error that should NEVER
1357 * happen. The hash table deletion is ONLY done through this call when the
1358 * main sessiond thread is torn down.
1361 app
= agent_find_app_by_sock(sock
);
1364 /* RCU read side lock is assumed to be held by this function. */
1365 agent_delete_app(app
);
1367 /* The application is freed in a RCU call but the socket is closed here. */
1368 agent_destroy_app(app
);
1373 * Clean-up the agent app hash table and destroy it.
1375 void agent_app_ht_clean(void)
1377 struct lttng_ht_node_ulong
*node
;
1378 struct lttng_ht_iter iter
;
1380 if (!agent_apps_ht_by_sock
) {
1384 cds_lfht_for_each_entry(agent_apps_ht_by_sock
->ht
, &iter
.iter
, node
, node
) {
1385 struct agent_app
*app
;
1387 app
= caa_container_of(node
, struct agent_app
, node
);
1388 agent_destroy_app_by_sock(app
->sock
->fd
);
1392 lttng_ht_destroy(agent_apps_ht_by_sock
);
1396 * Update a agent application (given socket) using the given agent.
1398 * Note that this function is most likely to be used with a tracing session
1399 * thus the caller should make sure to hold the appropriate lock(s).
1401 void agent_update(struct agent
*agt
, int sock
)
1404 struct agent_app
*app
;
1405 struct agent_event
*event
;
1406 struct lttng_ht_iter iter
;
1407 struct agent_app_ctx
*ctx
;
1412 DBG("Agent updating app socket %d", sock
);
1415 app
= agent_find_app_by_sock(sock
);
1417 * We are in the registration path thus if the application is gone,
1418 * there is a serious code flow error.
1421 cds_lfht_for_each_entry(agt
->events
->ht
, &iter
.iter
, event
, node
.node
) {
1422 /* Skip event if disabled. */
1423 if (!event
->enabled
) {
1427 ret
= enable_event(app
, event
);
1428 if (ret
!= LTTNG_OK
) {
1429 DBG2("Agent update unable to enable event %s on app pid: %d sock %d",
1430 event
->name
, app
->pid
, app
->sock
->fd
);
1431 /* Let's try the others here and don't assume the app is dead. */
1436 cds_list_for_each_entry_rcu(ctx
, &agt
->app_ctx_list
, list_node
) {
1437 ret
= app_context_op(app
, ctx
, AGENT_CMD_APP_CTX_ENABLE
);
1438 if (ret
!= LTTNG_OK
) {
1439 DBG2("Agent update unable to add application context %s:%s on app pid: %d sock %d",
1440 ctx
->provider_name
, ctx
->ctx_name
,
1441 app
->pid
, app
->sock
->fd
);