2 * Copyright (C) 2013 - David Goulet <dgoulet@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.
21 #include <urcu/uatomic.h>
23 #include <common/common.h>
24 #include <common/sessiond-comm/agent.h>
26 #include <common/compat/endian.h>
33 #define AGENT_RET_CODE_INDEX(code) (code - AGENT_RET_CODE_SUCCESS)
36 * Human readable agent return code.
38 static const char *error_string_array
[] = {
39 [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_SUCCESS
) ] = "Success",
40 [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_INVALID
) ] = "Invalid command",
41 [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_UNKNOWN_NAME
) ] = "Unknown logger name",
44 [ AGENT_RET_CODE_INDEX(AGENT_RET_CODE_NR
) ] = "Unknown code",
48 void log_reply_code(uint32_t in_reply_ret_code
)
50 int level
= PRINT_DBG3
;
52 * reply_ret_code and in_reply_ret_code are kept separate to have a
53 * sanitized value (used to retrieve the human readable string) and the
54 * original value which is logged as-is.
56 uint32_t reply_ret_code
= in_reply_ret_code
;
58 if (reply_ret_code
< AGENT_RET_CODE_SUCCESS
||
59 reply_ret_code
>= AGENT_RET_CODE_NR
) {
60 reply_ret_code
= AGENT_RET_CODE_NR
;
64 LOG(level
, "Agent replied with retcode: %s (%"PRIu32
")",
65 error_string_array
[AGENT_RET_CODE_INDEX(
71 * Match function for the events hash table lookup by name.
73 static int ht_match_event_by_name(struct cds_lfht_node
*node
,
76 struct agent_event
*event
;
77 const struct agent_ht_key
*key
;
82 event
= caa_container_of(node
, struct agent_event
, node
.node
);
85 /* Match 1 elements of the key: name. */
88 if (strncmp(event
->name
, key
->name
, sizeof(event
->name
)) != 0) {
99 * Match function for the events hash table lookup by name and loglevel.
101 static int ht_match_event(struct cds_lfht_node
*node
,
104 struct agent_event
*event
;
105 const struct agent_ht_key
*key
;
110 event
= caa_container_of(node
, struct agent_event
, node
.node
);
113 /* Match 2 elements of the key: name and loglevel. */
116 if (strncmp(event
->name
, key
->name
, sizeof(event
->name
)) != 0) {
120 if (event
->loglevel
!= key
->loglevel
) {
121 if (event
->loglevel_type
== LTTNG_EVENT_LOGLEVEL_ALL
&&
122 key
->loglevel
== 0 && event
->loglevel
== -1) {
135 * Add unique agent event based on the event name and loglevel.
137 static void add_unique_agent_event(struct lttng_ht
*ht
,
138 struct agent_event
*event
)
140 struct cds_lfht_node
*node_ptr
;
141 struct agent_ht_key key
;
147 key
.name
= event
->name
;
148 key
.loglevel
= event
->loglevel
;
150 node_ptr
= cds_lfht_add_unique(ht
->ht
,
151 ht
->hash_fct(event
->node
.key
, lttng_ht_seed
),
152 ht_match_event
, &key
, &event
->node
.node
);
153 assert(node_ptr
== &event
->node
.node
);
157 * URCU delayed agent event reclaim.
159 static void destroy_event_agent_rcu(struct rcu_head
*head
)
161 struct lttng_ht_node_str
*node
=
162 caa_container_of(head
, struct lttng_ht_node_str
, head
);
163 struct agent_event
*event
=
164 caa_container_of(node
, struct agent_event
, node
);
170 * URCU delayed agent app reclaim.
172 static void destroy_app_agent_rcu(struct rcu_head
*head
)
174 struct lttng_ht_node_ulong
*node
=
175 caa_container_of(head
, struct lttng_ht_node_ulong
, head
);
176 struct agent_app
*app
=
177 caa_container_of(node
, struct agent_app
, node
);
183 * Communication with the agent. Send the message header to the given socket in
186 * Return 0 on success or else a negative errno message of sendmsg() op.
188 static int send_header(struct lttcomm_sock
*sock
, uint64_t data_size
,
189 uint32_t cmd
, uint32_t cmd_version
)
193 struct lttcomm_agent_hdr msg
;
197 memset(&msg
, 0, sizeof(msg
));
198 msg
.data_size
= htobe64(data_size
);
199 msg
.cmd
= htobe32(cmd
);
200 msg
.cmd_version
= htobe32(cmd_version
);
202 size
= sock
->ops
->sendmsg(sock
, &msg
, sizeof(msg
), 0);
203 if (size
< sizeof(msg
)) {
214 * Communication call with the agent. Send the payload to the given socket. The
215 * header MUST be sent prior to this call.
217 * Return 0 on success or else a negative errno value of sendmsg() op.
219 static int send_payload(struct lttcomm_sock
*sock
, void *data
,
228 len
= sock
->ops
->sendmsg(sock
, data
, size
, 0);
240 * Communication call with the agent. Receive reply from the agent using the
243 * Return 0 on success or else a negative errno value from recvmsg() op.
245 static int recv_reply(struct lttcomm_sock
*sock
, void *buf
, size_t size
)
253 len
= sock
->ops
->recvmsg(sock
, buf
, size
, 0);
265 * Internal event listing for a given app. Populate events.
267 * Return number of element in the list or else a negative LTTNG_ERR* code.
268 * On success, the caller is responsible for freeing the memory
269 * allocated for "events".
271 static ssize_t
list_events(struct agent_app
*app
, struct lttng_event
**events
)
273 int ret
, i
, len
= 0, offset
= 0;
276 struct lttng_event
*tmp_events
= NULL
;
277 struct lttcomm_agent_list_reply
*reply
= NULL
;
278 struct lttcomm_agent_list_reply_hdr reply_hdr
;
284 DBG2("Agent listing events for app pid: %d and socket %d", app
->pid
,
287 ret
= send_header(app
->sock
, 0, AGENT_CMD_LIST
, 0);
292 /* Get list header so we know how much we'll receive. */
293 ret
= recv_reply(app
->sock
, &reply_hdr
, sizeof(reply_hdr
));
298 switch (be32toh(reply_hdr
.ret_code
)) {
299 case AGENT_RET_CODE_SUCCESS
:
300 data_size
= be32toh(reply_hdr
.data_size
) + sizeof(*reply
);
303 ERR("Agent returned an unknown code: %" PRIu32
,
304 be32toh(reply_hdr
.ret_code
));
305 ret
= LTTNG_ERR_FATAL
;
309 reply
= zmalloc(data_size
);
311 ret
= LTTNG_ERR_NOMEM
;
315 /* Get the list with the appropriate data size. */
316 ret
= recv_reply(app
->sock
, reply
, data_size
);
321 nb_event
= be32toh(reply
->nb_event
);
322 tmp_events
= zmalloc(sizeof(*tmp_events
) * nb_event
);
324 ret
= LTTNG_ERR_NOMEM
;
328 for (i
= 0; i
< nb_event
; i
++) {
330 strncpy(tmp_events
[i
].name
, reply
->payload
+ offset
,
331 sizeof(tmp_events
[i
].name
));
332 tmp_events
[i
].pid
= app
->pid
;
333 tmp_events
[i
].enabled
= -1;
334 len
= strlen(reply
->payload
+ offset
) + 1;
337 *events
= tmp_events
;
343 ret
= LTTNG_ERR_UST_LIST_FAIL
;
352 * Internal enable agent event on a agent application. This function
353 * communicates with the agent to enable a given event.
355 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
357 static int enable_event(struct agent_app
*app
, struct agent_event
*event
)
361 struct lttcomm_agent_enable msg
;
362 struct lttcomm_agent_generic_reply reply
;
368 DBG2("Agent enabling event %s for app pid: %d and socket %d", event
->name
,
369 app
->pid
, app
->sock
->fd
);
371 data_size
= sizeof(msg
);
373 ret
= send_header(app
->sock
, data_size
, AGENT_CMD_ENABLE
, 0);
378 memset(&msg
, 0, sizeof(msg
));
379 msg
.loglevel
= event
->loglevel
;
380 msg
.loglevel_type
= event
->loglevel_type
;
381 strncpy(msg
.name
, event
->name
, sizeof(msg
.name
));
382 ret
= send_payload(app
->sock
, &msg
, sizeof(msg
));
387 ret
= recv_reply(app
->sock
, &reply
, sizeof(reply
));
392 switch (be32toh(reply
.ret_code
)) {
393 case AGENT_RET_CODE_SUCCESS
:
395 case AGENT_RET_CODE_UNKNOWN_NAME
:
396 ret
= LTTNG_ERR_UST_EVENT_NOT_FOUND
;
399 ERR("Agent returned an unknown code: %" PRIu32
,
400 be32toh(reply
.ret_code
));
401 ret
= LTTNG_ERR_FATAL
;
408 ret
= LTTNG_ERR_UST_ENABLE_FAIL
;
414 * Internal disable agent event call on a agent application. This function
415 * communicates with the agent to disable a given event.
417 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
419 static int disable_event(struct agent_app
*app
, struct agent_event
*event
)
423 struct lttcomm_agent_disable msg
;
424 struct lttcomm_agent_generic_reply reply
;
430 DBG2("Agent disabling event %s for app pid: %d and socket %d", event
->name
,
431 app
->pid
, app
->sock
->fd
);
433 data_size
= sizeof(msg
);
435 ret
= send_header(app
->sock
, data_size
, AGENT_CMD_DISABLE
, 0);
440 memset(&msg
, 0, sizeof(msg
));
441 strncpy(msg
.name
, event
->name
, sizeof(msg
.name
));
442 ret
= send_payload(app
->sock
, &msg
, sizeof(msg
));
447 ret
= recv_reply(app
->sock
, &reply
, sizeof(reply
));
452 switch (be32toh(reply
.ret_code
)) {
453 case AGENT_RET_CODE_SUCCESS
:
455 case AGENT_RET_CODE_UNKNOWN_NAME
:
456 ret
= LTTNG_ERR_UST_EVENT_NOT_FOUND
;
459 ERR("Agent returned an unknown code: %" PRIu32
,
460 be32toh(reply
.ret_code
));
461 ret
= LTTNG_ERR_FATAL
;
468 ret
= LTTNG_ERR_UST_DISABLE_FAIL
;
474 * Send back the registration DONE command to a given agent application.
476 * Return 0 on success or else a negative value.
478 int agent_send_registration_done(struct agent_app
*app
)
483 DBG("Agent sending registration done to app socket %d", app
->sock
->fd
);
485 return send_header(app
->sock
, 0, AGENT_CMD_REG_DONE
, 0);
489 * Enable agent event on every agent applications registered with the session
492 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
494 int agent_enable_event(struct agent_event
*event
,
495 enum lttng_domain_type domain
)
498 struct agent_app
*app
;
499 struct lttng_ht_iter iter
;
505 cds_lfht_for_each_entry(agent_apps_ht_by_sock
->ht
, &iter
.iter
, app
,
507 if (app
->domain
!= domain
) {
511 /* Enable event on agent application through TCP socket. */
512 ret
= enable_event(app
, event
);
513 if (ret
!= LTTNG_OK
) {
527 * Disable agent event on every agent applications registered with the session
530 * Return LTTNG_OK on success or else a LTTNG_ERR* code.
532 int agent_disable_event(struct agent_event
*event
,
533 enum lttng_domain_type domain
)
536 struct agent_app
*app
;
537 struct lttng_ht_iter iter
;
540 if (!event
->enabled
) {
546 cds_lfht_for_each_entry(agent_apps_ht_by_sock
->ht
, &iter
.iter
, app
,
548 if (app
->domain
!= domain
) {
552 /* Enable event on agent application through TCP socket. */
553 ret
= disable_event(app
, event
);
554 if (ret
!= LTTNG_OK
) {
568 * Ask every agent for the list of possible event. Events is allocated with the
569 * events of every agent application.
571 * Return the number of events or else a negative value.
573 int agent_list_events(struct lttng_event
**events
,
574 enum lttng_domain_type domain
)
577 size_t nbmem
, count
= 0;
578 struct agent_app
*app
;
579 struct lttng_event
*tmp_events
= NULL
;
580 struct lttng_ht_iter iter
;
584 DBG2("Agent listing events for domain %d", domain
);
586 nbmem
= UST_APP_EVENT_LIST_SIZE
;
587 tmp_events
= zmalloc(nbmem
* sizeof(*tmp_events
));
589 PERROR("zmalloc agent list events");
595 cds_lfht_for_each_entry(agent_apps_ht_by_sock
->ht
, &iter
.iter
, app
,
598 struct lttng_event
*agent_events
;
600 /* Skip domain not asked by the list. */
601 if (app
->domain
!= domain
) {
605 nb_ev
= list_events(app
, &agent_events
);
611 if (count
+ nb_ev
> nbmem
) {
612 /* In case the realloc fails, we free the memory */
613 struct lttng_event
*new_tmp_events
;
616 new_nbmem
= max_t(size_t, count
+ nb_ev
, nbmem
<< 1);
617 DBG2("Reallocating agent event list from %zu to %zu entries",
619 new_tmp_events
= realloc(tmp_events
,
620 new_nbmem
* sizeof(*new_tmp_events
));
621 if (!new_tmp_events
) {
622 PERROR("realloc agent events");
627 /* Zero the new memory */
628 memset(new_tmp_events
+ nbmem
, 0,
629 (new_nbmem
- nbmem
) * sizeof(*new_tmp_events
));
631 tmp_events
= new_tmp_events
;
633 memcpy(tmp_events
+ count
, agent_events
,
634 nb_ev
* sizeof(*tmp_events
));
641 *events
= tmp_events
;
652 * Create a agent app object using the given PID.
654 * Return newly allocated object or else NULL on error.
656 struct agent_app
*agent_create_app(pid_t pid
, enum lttng_domain_type domain
,
657 struct lttcomm_sock
*sock
)
659 struct agent_app
*app
;
663 app
= zmalloc(sizeof(*app
));
665 PERROR("zmalloc agent create");
670 app
->domain
= domain
;
672 lttng_ht_node_init_ulong(&app
->node
, (unsigned long) app
->sock
->fd
);
679 * Lookup agent app by socket in the global hash table.
681 * RCU read side lock MUST be acquired.
683 * Return object if found else NULL.
685 struct agent_app
*agent_find_app_by_sock(int sock
)
687 struct lttng_ht_node_ulong
*node
;
688 struct lttng_ht_iter iter
;
689 struct agent_app
*app
;
693 lttng_ht_lookup(agent_apps_ht_by_sock
, (void *)((unsigned long) sock
), &iter
);
694 node
= lttng_ht_iter_get_node_ulong(&iter
);
698 app
= caa_container_of(node
, struct agent_app
, node
);
700 DBG3("Agent app pid %d found by sock %d.", app
->pid
, sock
);
704 DBG3("Agent app NOT found by sock %d.", sock
);
709 * Add agent application object to the global hash table.
711 void agent_add_app(struct agent_app
*app
)
715 DBG3("Agent adding app sock: %d and pid: %d to ht", app
->sock
->fd
, app
->pid
);
718 lttng_ht_add_unique_ulong(agent_apps_ht_by_sock
, &app
->node
);
723 * Delete agent application from the global hash table.
725 * rcu_read_lock() must be held by the caller.
727 void agent_delete_app(struct agent_app
*app
)
730 struct lttng_ht_iter iter
;
734 DBG3("Agent deleting app pid: %d and sock: %d", app
->pid
, app
->sock
->fd
);
736 iter
.iter
.node
= &app
->node
.node
;
737 ret
= lttng_ht_del(agent_apps_ht_by_sock
, &iter
);
742 * Destroy an agent application object by detaching it from its corresponding
743 * UST app if one is connected by closing the socket. Finally, perform a
744 * delayed memory reclaim.
746 void agent_destroy_app(struct agent_app
*app
)
751 app
->sock
->ops
->close(app
->sock
);
752 lttcomm_destroy_sock(app
->sock
);
755 call_rcu(&app
->node
.head
, destroy_app_agent_rcu
);
759 * Initialize an already allocated agent object.
761 * Return 0 on success or else a negative errno value.
763 int agent_init(struct agent
*agt
)
769 agt
->events
= lttng_ht_new(0, LTTNG_HT_TYPE_STRING
);
774 lttng_ht_node_init_u64(&agt
->node
, agt
->domain
);
783 * Add agent object to the given hash table.
785 void agent_add(struct agent
*agt
, struct lttng_ht
*ht
)
790 DBG3("Agent adding from domain %d", agt
->domain
);
793 lttng_ht_add_unique_u64(ht
, &agt
->node
);
798 * Create an agent object for the given domain.
800 * Return the allocated agent or NULL on error.
802 struct agent
*agent_create(enum lttng_domain_type domain
)
807 agt
= zmalloc(sizeof(*agt
));
811 agt
->domain
= domain
;
813 ret
= agent_init(agt
);
825 * Create a newly allocated agent event data structure. If name is valid, it's
826 * copied into the created event.
828 * Return a new object else NULL on error.
830 struct agent_event
*agent_create_event(const char *name
,
831 struct lttng_filter_bytecode
*filter
)
833 struct agent_event
*event
;
835 DBG3("Agent create new event with name %s", name
);
837 event
= zmalloc(sizeof(*event
));
843 strncpy(event
->name
, name
, sizeof(event
->name
));
844 event
->name
[sizeof(event
->name
) - 1] = '\0';
845 lttng_ht_node_init_str(&event
->node
, event
->name
);
849 event
->filter
= filter
;
857 * Unique add of a agent event to an agent object.
859 void agent_add_event(struct agent_event
*event
, struct agent
*agt
)
865 DBG3("Agent adding event %s", event
->name
);
868 add_unique_agent_event(agt
->events
, event
);
874 * Find a agent event in the given agent using name.
876 * RCU read side lock MUST be acquired.
878 * Return object if found else NULL.
880 struct agent_event
*agent_find_event_by_name(const char *name
,
883 struct lttng_ht_node_str
*node
;
884 struct lttng_ht_iter iter
;
886 struct agent_ht_key key
;
895 cds_lfht_lookup(ht
->ht
, ht
->hash_fct((void *) name
, lttng_ht_seed
),
896 ht_match_event_by_name
, &key
, &iter
.iter
);
897 node
= lttng_ht_iter_get_node_str(&iter
);
902 DBG3("Agent event found %s by name.", name
);
903 return caa_container_of(node
, struct agent_event
, node
);
906 DBG3("Agent NOT found by name %s.", name
);
911 * Find a agent event in the given agent using name and loglevel.
913 * RCU read side lock MUST be acquired.
915 * Return object if found else NULL.
917 struct agent_event
*agent_find_event(const char *name
, int loglevel
,
920 struct lttng_ht_node_str
*node
;
921 struct lttng_ht_iter iter
;
923 struct agent_ht_key key
;
931 key
.loglevel
= loglevel
;
933 cds_lfht_lookup(ht
->ht
, ht
->hash_fct((void *) name
, lttng_ht_seed
),
934 ht_match_event
, &key
, &iter
.iter
);
935 node
= lttng_ht_iter_get_node_str(&iter
);
940 DBG3("Agent event found %s.", name
);
941 return caa_container_of(node
, struct agent_event
, node
);
944 DBG3("Agent event NOT found %s.", name
);
949 * Free given agent event. This event must not be globally visible at this
950 * point (only expected to be used on failure just after event creation). After
951 * this call, the pointer is not usable anymore.
953 void agent_destroy_event(struct agent_event
*event
)
962 * Destroy an agent completely. Note that the given pointer is NOT freed
963 * thus a reference to static or stack data can be passed to this function.
965 void agent_destroy(struct agent
*agt
)
967 struct lttng_ht_node_str
*node
;
968 struct lttng_ht_iter iter
;
972 DBG3("Agent destroy");
975 * Just ignore if no events hash table exists. This is possible if for
976 * instance an agent object was allocated but not initialized.
983 cds_lfht_for_each_entry(agt
->events
->ht
, &iter
.iter
, node
, node
) {
985 struct agent_event
*event
;
988 * When destroying an event, we have to try to disable it on the agent
989 * side so the event stops generating data. The return value is not
990 * important since we have to continue anyway destroying the object.
992 event
= caa_container_of(node
, struct agent_event
, node
);
993 (void) agent_disable_event(event
, agt
->domain
);
995 ret
= lttng_ht_del(agt
->events
, &iter
);
997 call_rcu(&node
->head
, destroy_event_agent_rcu
);
1001 ht_cleanup_push(agt
->events
);
1005 * Allocate agent_apps_ht_by_sock.
1007 int agent_app_ht_alloc(void)
1011 agent_apps_ht_by_sock
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
1012 if (!agent_apps_ht_by_sock
) {
1020 * Destroy a agent application by socket.
1022 void agent_destroy_app_by_sock(int sock
)
1024 struct agent_app
*app
;
1029 * Not finding an application is a very important error that should NEVER
1030 * happen. The hash table deletion is ONLY done through this call when the
1031 * main sessiond thread is torn down.
1034 app
= agent_find_app_by_sock(sock
);
1037 /* RCU read side lock is assumed to be held by this function. */
1038 agent_delete_app(app
);
1040 /* The application is freed in a RCU call but the socket is closed here. */
1041 agent_destroy_app(app
);
1046 * Clean-up the agent app hash table and destroy it.
1048 void agent_app_ht_clean(void)
1050 struct lttng_ht_node_ulong
*node
;
1051 struct lttng_ht_iter iter
;
1053 if (!agent_apps_ht_by_sock
) {
1057 cds_lfht_for_each_entry(agent_apps_ht_by_sock
->ht
, &iter
.iter
, node
, node
) {
1058 struct agent_app
*app
;
1060 app
= caa_container_of(node
, struct agent_app
, node
);
1061 agent_destroy_app_by_sock(app
->sock
->fd
);
1065 lttng_ht_destroy(agent_apps_ht_by_sock
);
1069 * Update a agent application (given socket) using the given agent.
1071 * Note that this function is most likely to be used with a tracing session
1072 * thus the caller should make sure to hold the appropriate lock(s).
1074 void agent_update(struct agent
*agt
, int sock
)
1077 struct agent_app
*app
;
1078 struct agent_event
*event
;
1079 struct lttng_ht_iter iter
;
1084 DBG("Agent updating app socket %d", sock
);
1087 cds_lfht_for_each_entry(agt
->events
->ht
, &iter
.iter
, event
, node
.node
) {
1088 /* Skip event if disabled. */
1089 if (!event
->enabled
) {
1093 app
= agent_find_app_by_sock(sock
);
1095 * We are in the registration path thus if the application is gone,
1096 * there is a serious code flow error.
1100 ret
= enable_event(app
, event
);
1101 if (ret
!= LTTNG_OK
) {
1102 DBG2("Agent update unable to enable event %s on app pid: %d sock %d",
1103 event
->name
, app
->pid
, app
->sock
->fd
);
1104 /* Let's try the others here and don't assume the app is dead. */