2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 #include <lttng/ust-ctl.h>
27 #include <sys/socket.h>
29 #include <sys/types.h>
32 #include <urcu/list.h>
35 #include <common/common.h>
36 #include <common/sessiond-comm/sessiond-comm.h>
37 #include <common/relayd/relayd.h>
38 #include <common/compat/fcntl.h>
39 #include <common/consumer-metadata-cache.h>
40 #include <common/consumer-stream.h>
41 #include <common/consumer-timer.h>
42 #include <common/utils.h>
44 #include "ust-consumer.h"
46 extern struct lttng_consumer_global_data consumer_data
;
47 extern int consumer_poll_timeout
;
48 extern volatile int consumer_quit
;
51 * Free channel object and all streams associated with it. This MUST be used
52 * only and only if the channel has _NEVER_ been added to the global channel
55 static void destroy_channel(struct lttng_consumer_channel
*channel
)
57 struct lttng_consumer_stream
*stream
, *stmp
;
61 DBG("UST consumer cleaning stream list");
63 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
65 cds_list_del(&stream
->send_node
);
66 ustctl_destroy_stream(stream
->ustream
);
71 * If a channel is available meaning that was created before the streams
75 lttng_ustconsumer_del_channel(channel
);
81 * Add channel to internal consumer state.
83 * Returns 0 on success or else a negative value.
85 static int add_channel(struct lttng_consumer_channel
*channel
,
86 struct lttng_consumer_local_data
*ctx
)
93 if (ctx
->on_recv_channel
!= NULL
) {
94 ret
= ctx
->on_recv_channel(channel
);
96 ret
= consumer_add_channel(channel
, ctx
);
98 /* Most likely an ENOMEM. */
99 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
103 ret
= consumer_add_channel(channel
, ctx
);
106 DBG("UST consumer channel added (key: %" PRIu64
")", channel
->key
);
113 * Allocate and return a consumer channel object.
115 static struct lttng_consumer_channel
*allocate_channel(uint64_t session_id
,
116 const char *pathname
, const char *name
, uid_t uid
, gid_t gid
,
117 uint64_t relayd_id
, uint64_t key
, enum lttng_event_output output
,
118 uint64_t tracefile_size
, uint64_t tracefile_count
,
119 uint64_t session_id_per_pid
, unsigned int monitor
)
124 return consumer_allocate_channel(key
, session_id
, pathname
, name
, uid
,
125 gid
, relayd_id
, output
, tracefile_size
,
126 tracefile_count
, session_id_per_pid
, monitor
);
130 * Allocate and return a consumer stream object. If _alloc_ret is not NULL, the
131 * error value if applicable is set in it else it is kept untouched.
133 * Return NULL on error else the newly allocated stream object.
135 static struct lttng_consumer_stream
*allocate_stream(int cpu
, int key
,
136 struct lttng_consumer_channel
*channel
,
137 struct lttng_consumer_local_data
*ctx
, int *_alloc_ret
)
140 struct lttng_consumer_stream
*stream
= NULL
;
145 stream
= consumer_allocate_stream(channel
->key
,
147 LTTNG_CONSUMER_ACTIVE_STREAM
,
157 if (stream
== NULL
) {
161 * We could not find the channel. Can happen if cpu hotplug
162 * happens while tearing down.
164 DBG3("Could not find channel");
169 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
175 stream
->chan
= channel
;
179 *_alloc_ret
= alloc_ret
;
185 * Send the given stream pointer to the corresponding thread.
187 * Returns 0 on success else a negative value.
189 static int send_stream_to_thread(struct lttng_consumer_stream
*stream
,
190 struct lttng_consumer_local_data
*ctx
)
193 struct lttng_pipe
*stream_pipe
;
195 /* Get the right pipe where the stream will be sent. */
196 if (stream
->metadata_flag
) {
197 stream_pipe
= ctx
->consumer_metadata_pipe
;
199 stream_pipe
= ctx
->consumer_data_pipe
;
202 ret
= lttng_pipe_write(stream_pipe
, &stream
, sizeof(stream
));
204 ERR("Consumer write %s stream to pipe %d",
205 stream
->metadata_flag
? "metadata" : "data",
206 lttng_pipe_get_writefd(stream_pipe
));
213 * Create streams for the given channel using liblttng-ust-ctl.
215 * Return 0 on success else a negative value.
217 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
218 struct lttng_consumer_local_data
*ctx
)
221 struct ustctl_consumer_stream
*ustream
;
222 struct lttng_consumer_stream
*stream
;
228 * While a stream is available from ustctl. When NULL is returned, we've
229 * reached the end of the possible stream for the channel.
231 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
233 int ust_metadata_pipe
[2];
235 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& channel
->monitor
) {
236 ret
= utils_create_pipe_cloexec_nonblock(ust_metadata_pipe
);
238 ERR("Create ust metadata poll pipe");
241 wait_fd
= ust_metadata_pipe
[0];
243 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
246 /* Allocate consumer stream object. */
247 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
251 stream
->ustream
= ustream
;
253 * Store it so we can save multiple function calls afterwards since
254 * this value is used heavily in the stream threads. This is UST
255 * specific so this is why it's done after allocation.
257 stream
->wait_fd
= wait_fd
;
260 * Increment channel refcount since the channel reference has now been
261 * assigned in the allocation process above.
263 if (stream
->chan
->monitor
) {
264 uatomic_inc(&stream
->chan
->refcount
);
268 * Order is important this is why a list is used. On error, the caller
269 * should clean this list.
271 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
273 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
274 &stream
->max_sb_size
);
276 ERR("ustctl_get_max_subbuf_size failed for stream %s",
281 /* Do actions once stream has been received. */
282 if (ctx
->on_recv_stream
) {
283 ret
= ctx
->on_recv_stream(stream
);
289 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
290 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
292 /* Set next CPU stream. */
293 channel
->streams
.count
= ++cpu
;
295 /* Keep stream reference when creating metadata. */
296 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
297 channel
->metadata_stream
= stream
;
298 stream
->ust_metadata_poll_pipe
[0] = ust_metadata_pipe
[0];
299 stream
->ust_metadata_poll_pipe
[1] = ust_metadata_pipe
[1];
311 * Create an UST channel with the given attributes and send it to the session
312 * daemon using the ust ctl API.
314 * Return 0 on success or else a negative value.
316 static int create_ust_channel(struct ustctl_consumer_channel_attr
*attr
,
317 struct ustctl_consumer_channel
**chanp
)
320 struct ustctl_consumer_channel
*channel
;
325 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
326 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
327 "switch_timer_interval: %u, read_timer_interval: %u, "
328 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
329 attr
->num_subbuf
, attr
->switch_timer_interval
,
330 attr
->read_timer_interval
, attr
->output
, attr
->type
);
332 channel
= ustctl_create_channel(attr
);
347 * Send a single given stream to the session daemon using the sock.
349 * Return 0 on success else a negative value.
351 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
358 DBG("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
360 /* Send stream to session daemon. */
361 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
371 * Send channel to sessiond.
373 * Return 0 on success or else a negative value.
375 static int send_sessiond_channel(int sock
,
376 struct lttng_consumer_channel
*channel
,
377 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
379 int ret
, ret_code
= LTTNG_OK
;
380 struct lttng_consumer_stream
*stream
;
386 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
388 if (channel
->relayd_id
!= (uint64_t) -1ULL) {
389 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
390 /* Try to send the stream to the relayd if one is available. */
391 ret
= consumer_send_relayd_stream(stream
, stream
->chan
->pathname
);
394 * Flag that the relayd was the problem here probably due to a
395 * communicaton error on the socket.
400 ret_code
= LTTNG_ERR_RELAYD_CONNECT_FAIL
;
405 /* Inform sessiond that we are about to send channel and streams. */
406 ret
= consumer_send_status_msg(sock
, ret_code
);
407 if (ret
< 0 || ret_code
!= LTTNG_OK
) {
409 * Either the session daemon is not responding or the relayd died so we
415 /* Send channel to sessiond. */
416 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
421 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
426 /* The channel was sent successfully to the sessiond at this point. */
427 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
428 /* Send stream to session daemon. */
429 ret
= send_sessiond_stream(sock
, stream
);
435 /* Tell sessiond there is no more stream. */
436 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
441 DBG("UST consumer NULL stream sent to sessiond");
446 if (ret_code
!= LTTNG_OK
) {
453 * Creates a channel and streams and add the channel it to the channel internal
454 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
457 * Return 0 on success or else, a negative value is returned and the channel
458 * MUST be destroyed by consumer_del_channel().
460 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
461 struct lttng_consumer_channel
*channel
,
462 struct ustctl_consumer_channel_attr
*attr
)
471 * This value is still used by the kernel consumer since for the kernel,
472 * the stream ownership is not IN the consumer so we need to have the
473 * number of left stream that needs to be initialized so we can know when
474 * to delete the channel (see consumer.c).
476 * As for the user space tracer now, the consumer creates and sends the
477 * stream to the session daemon which only sends them to the application
478 * once every stream of a channel is received making this value useless
479 * because we they will be added to the poll thread before the application
480 * receives them. This ensures that a stream can not hang up during
481 * initilization of a channel.
483 channel
->nb_init_stream_left
= 0;
485 /* The reply msg status is handled in the following call. */
486 ret
= create_ust_channel(attr
, &channel
->uchan
);
491 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
494 * For the snapshots (no monitor), we create the metadata streams
495 * on demand, not during the channel creation.
497 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& !channel
->monitor
) {
502 /* Open all streams for this channel. */
503 ret
= create_ust_streams(channel
, ctx
);
513 * Send all stream of a channel to the right thread handling it.
515 * On error, return a negative value else 0 on success.
517 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
518 struct lttng_consumer_local_data
*ctx
)
521 struct lttng_consumer_stream
*stream
, *stmp
;
526 /* Send streams to the corresponding thread. */
527 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
529 /* Sending the stream to the thread. */
530 ret
= send_stream_to_thread(stream
, ctx
);
533 * If we are unable to send the stream to the thread, there is
534 * a big problem so just stop everything.
539 /* Remove node from the channel stream list. */
540 cds_list_del(&stream
->send_node
);
543 * From this point on, the stream's ownership has been moved away from
544 * the channel and becomes globally visible.
546 stream
->globally_visible
= 1;
554 * Flush channel's streams using the given key to retrieve the channel.
556 * Return 0 on success else an LTTng error code.
558 static int flush_channel(uint64_t chan_key
)
561 struct lttng_consumer_channel
*channel
;
562 struct lttng_consumer_stream
*stream
;
564 struct lttng_ht_iter iter
;
566 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
569 channel
= consumer_find_channel(chan_key
);
571 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
572 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
576 ht
= consumer_data
.stream_per_chan_id_ht
;
578 /* For each stream of the channel id, flush it. */
579 cds_lfht_for_each_entry_duplicate(ht
->ht
,
580 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
581 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
582 ustctl_flush_buffer(stream
->ustream
, 1);
590 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
591 * RCU read side lock MUST be acquired before calling this function.
593 * Return 0 on success else an LTTng error code.
595 static int close_metadata(uint64_t chan_key
)
598 struct lttng_consumer_channel
*channel
;
600 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
602 channel
= consumer_find_channel(chan_key
);
605 * This is possible if the metadata thread has issue a delete because
606 * the endpoint point of the stream hung up. There is no way the
607 * session daemon can know about it thus use a DBG instead of an actual
610 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
611 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
615 pthread_mutex_lock(&consumer_data
.lock
);
616 pthread_mutex_lock(&channel
->lock
);
617 pthread_mutex_lock(&channel
->timer_lock
);
619 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
623 if (channel
->switch_timer_enabled
== 1) {
624 DBG("Deleting timer on metadata channel");
625 consumer_timer_switch_stop(channel
);
628 if (channel
->metadata_stream
) {
629 ret
= ustctl_stream_close_wakeup_fd(channel
->metadata_stream
->ustream
);
631 ERR("UST consumer unable to close fd of metadata (ret: %d)", ret
);
632 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
635 if (channel
->monitor
) {
636 /* close the read-side in consumer_del_metadata_stream */
637 ret
= close(channel
->metadata_stream
->ust_metadata_poll_pipe
[1]);
639 PERROR("Close UST metadata write-side poll pipe");
645 pthread_mutex_unlock(&channel
->timer_lock
);
646 pthread_mutex_unlock(&channel
->lock
);
647 pthread_mutex_unlock(&consumer_data
.lock
);
653 * RCU read side lock MUST be acquired before calling this function.
655 * Return 0 on success else an LTTng error code.
657 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
660 struct lttng_consumer_channel
*metadata
;
662 DBG("UST consumer setup metadata key %" PRIu64
, key
);
664 metadata
= consumer_find_channel(key
);
666 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
667 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
672 * In no monitor mode, the metadata channel has no stream(s) so skip the
673 * ownership transfer to the metadata thread.
675 if (!metadata
->monitor
) {
676 DBG("Metadata channel in no monitor");
682 * Send metadata stream to relayd if one available. Availability is
683 * known if the stream is still in the list of the channel.
685 if (cds_list_empty(&metadata
->streams
.head
)) {
686 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
687 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
688 goto error_no_stream
;
691 /* Send metadata stream to relayd if needed. */
692 if (metadata
->metadata_stream
->net_seq_idx
!= (uint64_t) -1ULL) {
693 ret
= consumer_send_relayd_stream(metadata
->metadata_stream
,
696 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
701 ret
= send_streams_to_thread(metadata
, ctx
);
704 * If we are unable to send the stream to the thread, there is
705 * a big problem so just stop everything.
707 ret
= LTTCOMM_CONSUMERD_FATAL
;
710 /* List MUST be empty after or else it could be reused. */
711 assert(cds_list_empty(&metadata
->streams
.head
));
718 * Delete metadata channel on error. At this point, the metadata stream can
719 * NOT be monitored by the metadata thread thus having the guarantee that
720 * the stream is still in the local stream list of the channel. This call
721 * will make sure to clean that list.
723 cds_list_del(&metadata
->metadata_stream
->send_node
);
724 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
731 * Snapshot the whole metadata.
733 * Returns 0 on success, < 0 on error
735 static int snapshot_metadata(uint64_t key
, char *path
, uint64_t relayd_id
,
736 struct lttng_consumer_local_data
*ctx
)
739 struct lttng_consumer_channel
*metadata_channel
;
740 struct lttng_consumer_stream
*metadata_stream
;
745 DBG("UST consumer snapshot metadata with key %" PRIu64
" at path %s",
750 metadata_channel
= consumer_find_channel(key
);
751 if (!metadata_channel
) {
752 ERR("UST snapshot metadata channel not found for key %lu", key
);
756 assert(!metadata_channel
->monitor
);
759 * Ask the sessiond if we have new metadata waiting and update the
760 * consumer metadata cache.
762 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
);
768 * The metadata stream is NOT created in no monitor mode when the channel
769 * is created on a sessiond ask channel command.
771 ret
= create_ust_streams(metadata_channel
, ctx
);
776 metadata_stream
= metadata_channel
->metadata_stream
;
777 assert(metadata_stream
);
779 if (relayd_id
!= (uint64_t) -1ULL) {
780 metadata_stream
->net_seq_idx
= relayd_id
;
781 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
786 ret
= utils_create_stream_file(path
, metadata_stream
->name
,
787 metadata_stream
->chan
->tracefile_size
,
788 metadata_stream
->tracefile_count_current
,
789 metadata_stream
->uid
, metadata_stream
->gid
);
793 metadata_stream
->out_fd
= ret
;
794 metadata_stream
->tracefile_size_current
= 0;
797 pthread_mutex_lock(&metadata_channel
->metadata_cache
->lock
);
800 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
);
807 pthread_mutex_unlock(&metadata_channel
->metadata_cache
->lock
);
811 * Clean up the stream completly because the next snapshot will use a new
814 cds_list_del(&metadata_stream
->send_node
);
815 consumer_stream_destroy(metadata_stream
, NULL
);
816 metadata_channel
->metadata_stream
= NULL
;
824 * Take a snapshot of all the stream of a channel.
826 * Returns 0 on success, < 0 on error
828 static int snapshot_channel(uint64_t key
, char *path
, uint64_t relayd_id
,
829 uint64_t max_stream_size
, struct lttng_consumer_local_data
*ctx
)
832 unsigned use_relayd
= 0;
833 unsigned long consumed_pos
, produced_pos
;
834 struct lttng_consumer_channel
*channel
;
835 struct lttng_consumer_stream
*stream
;
842 if (relayd_id
!= (uint64_t) -1ULL) {
846 channel
= consumer_find_channel(key
);
848 ERR("UST snapshot channel not found for key %lu", key
);
852 assert(!channel
->monitor
);
853 DBG("UST consumer snapshot channel %lu", key
);
855 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
856 /* Lock stream because we are about to change its state. */
857 pthread_mutex_lock(&stream
->lock
);
858 stream
->net_seq_idx
= relayd_id
;
861 ret
= consumer_send_relayd_stream(stream
, path
);
866 ret
= utils_create_stream_file(path
, stream
->name
,
867 stream
->chan
->tracefile_size
,
868 stream
->tracefile_count_current
,
869 stream
->uid
, stream
->gid
);
873 stream
->out_fd
= ret
;
874 stream
->tracefile_size_current
= 0;
876 DBG("UST consumer snapshot stream %s/%s (%" PRIu64
")", path
,
877 stream
->name
, stream
->key
);
880 ustctl_flush_buffer(stream
->ustream
, 1);
882 ret
= lttng_ustconsumer_take_snapshot(stream
);
884 ERR("Taking UST snapshot");
888 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
890 ERR("Produced UST snapshot position");
894 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
896 ERR("Consumerd UST snapshot position");
901 * The original value is sent back if max stream size is larger than
902 * the possible size of the snapshot. Also, we asume that the session
903 * daemon should never send a maximum stream size that is lower than
906 consumed_pos
= consumer_get_consumed_maxsize(consumed_pos
,
907 produced_pos
, max_stream_size
);
909 while (consumed_pos
< produced_pos
) {
911 unsigned long len
, padded_len
;
913 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
915 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
917 if (ret
!= -EAGAIN
) {
918 PERROR("ustctl_get_subbuf snapshot");
919 goto error_close_stream
;
921 DBG("UST consumer get subbuf failed. Skipping it.");
922 consumed_pos
+= stream
->max_sb_size
;
926 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
928 ERR("Snapshot ustctl_get_subbuf_size");
929 goto error_put_subbuf
;
932 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
934 ERR("Snapshot ustctl_get_padded_subbuf_size");
935 goto error_put_subbuf
;
938 read_len
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, len
,
941 if (read_len
!= len
) {
943 goto error_put_subbuf
;
946 if (read_len
!= padded_len
) {
948 goto error_put_subbuf
;
952 ret
= ustctl_put_subbuf(stream
->ustream
);
954 ERR("Snapshot ustctl_put_subbuf");
955 goto error_close_stream
;
957 consumed_pos
+= stream
->max_sb_size
;
960 /* Simply close the stream so we can use it on the next snapshot. */
961 consumer_stream_close(stream
);
962 pthread_mutex_unlock(&stream
->lock
);
969 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
970 ERR("Snapshot ustctl_put_subbuf");
973 consumer_stream_close(stream
);
975 pthread_mutex_unlock(&stream
->lock
);
982 * Receive the metadata updates from the sessiond.
984 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
985 uint64_t len
, struct lttng_consumer_channel
*channel
)
987 int ret
, ret_code
= LTTNG_OK
;
990 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
992 metadata_str
= zmalloc(len
* sizeof(char));
994 PERROR("zmalloc metadata string");
995 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
999 /* Receive metadata string. */
1000 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1002 /* Session daemon is dead so return gracefully. */
1007 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1008 ret
= consumer_metadata_cache_write(channel
, offset
, len
, metadata_str
);
1010 /* Unable to handle metadata. Notify session daemon. */
1011 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1013 * Skip metadata flush on write error since the offset and len might
1014 * not have been updated which could create an infinite loop below when
1015 * waiting for the metadata cache to be flushed.
1017 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1020 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1022 while (consumer_metadata_cache_flushed(channel
, offset
+ len
)) {
1023 DBG("Waiting for metadata to be flushed");
1024 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1034 * Receive command from session daemon and process it.
1036 * Return 1 on success else a negative value or 0.
1038 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1039 int sock
, struct pollfd
*consumer_sockpoll
)
1042 enum lttng_error_code ret_code
= LTTNG_OK
;
1043 struct lttcomm_consumer_msg msg
;
1044 struct lttng_consumer_channel
*channel
= NULL
;
1046 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1047 if (ret
!= sizeof(msg
)) {
1048 DBG("Consumer received unexpected message size %zd (expects %zu)",
1051 * The ret value might 0 meaning an orderly shutdown but this is ok
1052 * since the caller handles this.
1055 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1060 if (msg
.cmd_type
== LTTNG_CONSUMER_STOP
) {
1062 * Notify the session daemon that the command is completed.
1064 * On transport layer error, the function call will print an error
1065 * message so handling the returned code is a bit useless since we
1066 * return an error code anyway.
1068 (void) consumer_send_status_msg(sock
, ret_code
);
1072 /* relayd needs RCU read-side lock */
1075 switch (msg
.cmd_type
) {
1076 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1078 /* Session daemon status message are handled in the following call. */
1079 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1080 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1081 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
);
1084 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1086 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1087 struct consumer_relayd_sock_pair
*relayd
;
1089 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1091 /* Get relayd reference if exists. */
1092 relayd
= consumer_find_relayd(index
);
1093 if (relayd
== NULL
) {
1094 DBG("Unable to find relayd %" PRIu64
, index
);
1095 ret_code
= LTTNG_ERR_NO_CONSUMER
;
1099 * Each relayd socket pair has a refcount of stream attached to it
1100 * which tells if the relayd is still active or not depending on the
1103 * This will set the destroy flag of the relayd object and destroy it
1104 * if the refcount reaches zero when called.
1106 * The destroy can happen either here or when a stream fd hangs up.
1109 consumer_flag_relayd_for_destroy(relayd
);
1112 goto end_msg_sessiond
;
1114 case LTTNG_CONSUMER_UPDATE_STREAM
:
1119 case LTTNG_CONSUMER_DATA_PENDING
:
1121 int ret
, is_data_pending
;
1122 uint64_t id
= msg
.u
.data_pending
.session_id
;
1124 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1126 is_data_pending
= consumer_data_pending(id
);
1128 /* Send back returned value to session daemon */
1129 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1130 sizeof(is_data_pending
));
1132 DBG("Error when sending the data pending ret code: %d", ret
);
1137 * No need to send back a status message since the data pending
1138 * returned value is the response.
1142 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1145 struct ustctl_consumer_channel_attr attr
;
1147 /* Create a plain object and reserve a channel key. */
1148 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
1149 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
1150 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
1151 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
1152 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1153 msg
.u
.ask_channel
.tracefile_size
,
1154 msg
.u
.ask_channel
.tracefile_count
,
1155 msg
.u
.ask_channel
.session_id_per_pid
,
1156 msg
.u
.ask_channel
.monitor
);
1158 goto end_channel_error
;
1161 /* Build channel attributes from received message. */
1162 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1163 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1164 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1165 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1166 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1167 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1168 attr
.output
= msg
.u
.ask_channel
.output
;
1169 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1171 /* Translate and save channel type. */
1172 switch (msg
.u
.ask_channel
.type
) {
1173 case LTTNG_UST_CHAN_PER_CPU
:
1174 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1175 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1177 * Set refcount to 1 for owner. Below, we will
1178 * pass ownership to the
1179 * consumer_thread_channel_poll() thread.
1181 channel
->refcount
= 1;
1183 case LTTNG_UST_CHAN_METADATA
:
1184 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1185 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1192 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
1194 goto end_channel_error
;
1197 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1198 ret
= consumer_metadata_cache_allocate(channel
);
1200 ERR("Allocating metadata cache");
1201 goto end_channel_error
;
1203 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1204 attr
.switch_timer_interval
= 0;
1208 * Add the channel to the internal state AFTER all streams were created
1209 * and successfully sent to session daemon. This way, all streams must
1210 * be ready before this channel is visible to the threads.
1211 * If add_channel succeeds, ownership of the channel is
1212 * passed to consumer_thread_channel_poll().
1214 ret
= add_channel(channel
, ctx
);
1216 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1217 if (channel
->switch_timer_enabled
== 1) {
1218 consumer_timer_switch_stop(channel
);
1220 consumer_metadata_cache_destroy(channel
);
1222 goto end_channel_error
;
1226 * Channel and streams are now created. Inform the session daemon that
1227 * everything went well and should wait to receive the channel and
1228 * streams with ustctl API.
1230 ret
= consumer_send_status_channel(sock
, channel
);
1233 * There is probably a problem on the socket.
1240 case LTTNG_CONSUMER_GET_CHANNEL
:
1242 int ret
, relayd_err
= 0;
1243 uint64_t key
= msg
.u
.get_channel
.key
;
1244 struct lttng_consumer_channel
*channel
;
1246 channel
= consumer_find_channel(key
);
1248 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1249 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
1250 goto end_msg_sessiond
;
1253 /* Send everything to sessiond. */
1254 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1258 * We were unable to send to the relayd the stream so avoid
1259 * sending back a fatal error to the thread since this is OK
1260 * and the consumer can continue its work. The above call
1261 * has sent the error status message to the sessiond.
1266 * The communicaton was broken hence there is a bad state between
1267 * the consumer and sessiond so stop everything.
1273 * In no monitor mode, the streams ownership is kept inside the channel
1274 * so don't send them to the data thread.
1276 if (!channel
->monitor
) {
1277 goto end_msg_sessiond
;
1280 ret
= send_streams_to_thread(channel
, ctx
);
1283 * If we are unable to send the stream to the thread, there is
1284 * a big problem so just stop everything.
1288 /* List MUST be empty after or else it could be reused. */
1289 assert(cds_list_empty(&channel
->streams
.head
));
1290 goto end_msg_sessiond
;
1292 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1294 uint64_t key
= msg
.u
.destroy_channel
.key
;
1297 * Only called if streams have not been sent to stream
1298 * manager thread. However, channel has been sent to
1299 * channel manager thread.
1301 notify_thread_del_channel(ctx
, key
);
1302 goto end_msg_sessiond
;
1304 case LTTNG_CONSUMER_CLOSE_METADATA
:
1308 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1313 goto end_msg_sessiond
;
1315 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1319 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1324 goto end_msg_sessiond
;
1326 case LTTNG_CONSUMER_PUSH_METADATA
:
1329 uint64_t len
= msg
.u
.push_metadata
.len
;
1330 uint64_t key
= msg
.u
.push_metadata
.key
;
1331 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1332 struct lttng_consumer_channel
*channel
;
1334 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1337 channel
= consumer_find_channel(key
);
1339 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
1340 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
1341 goto end_msg_sessiond
;
1344 /* Tell session daemon we are ready to receive the metadata. */
1345 ret
= consumer_send_status_msg(sock
, LTTNG_OK
);
1347 /* Somehow, the session daemon is not responding anymore. */
1351 /* Wait for more data. */
1352 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
1356 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1359 /* error receiving from sessiond */
1363 goto end_msg_sessiond
;
1366 case LTTNG_CONSUMER_SETUP_METADATA
:
1370 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1374 goto end_msg_sessiond
;
1376 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1378 if (msg
.u
.snapshot_channel
.metadata
) {
1379 ret
= snapshot_metadata(msg
.u
.snapshot_channel
.key
,
1380 msg
.u
.snapshot_channel
.pathname
,
1381 msg
.u
.snapshot_channel
.relayd_id
,
1384 ERR("Snapshot metadata failed");
1385 ret_code
= LTTNG_ERR_UST_META_FAIL
;
1388 ret
= snapshot_channel(msg
.u
.snapshot_channel
.key
,
1389 msg
.u
.snapshot_channel
.pathname
,
1390 msg
.u
.snapshot_channel
.relayd_id
,
1391 msg
.u
.snapshot_channel
.max_stream_size
,
1394 ERR("Snapshot channel failed");
1395 ret_code
= LTTNG_ERR_UST_CHAN_FAIL
;
1399 ret
= consumer_send_status_msg(sock
, ret_code
);
1401 /* Somehow, the session daemon is not responding anymore. */
1414 * Return 1 to indicate success since the 0 value can be a socket
1415 * shutdown during the recv() or send() call.
1421 * The returned value here is not useful since either way we'll return 1 to
1422 * the caller because the session daemon socket management is done
1423 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1425 ret
= consumer_send_status_msg(sock
, ret_code
);
1434 * Free channel here since no one has a reference to it. We don't
1435 * free after that because a stream can store this pointer.
1437 destroy_channel(channel
);
1439 /* We have to send a status channel message indicating an error. */
1440 ret
= consumer_send_status_channel(sock
, NULL
);
1442 /* Stop everything if session daemon can not be notified. */
1449 /* This will issue a consumer stop. */
1454 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1455 * compiled out, we isolate it in this library.
1457 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1461 assert(stream
->ustream
);
1463 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1467 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1468 * compiled out, we isolate it in this library.
1470 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1473 assert(stream
->ustream
);
1475 return ustctl_get_mmap_base(stream
->ustream
);
1479 * Take a snapshot for a specific fd
1481 * Returns 0 on success, < 0 on error
1483 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1486 assert(stream
->ustream
);
1488 return ustctl_snapshot(stream
->ustream
);
1492 * Get the produced position
1494 * Returns 0 on success, < 0 on error
1496 int lttng_ustconsumer_get_produced_snapshot(
1497 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1500 assert(stream
->ustream
);
1503 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1507 * Get the consumed position
1509 * Returns 0 on success, < 0 on error
1511 int lttng_ustconsumer_get_consumed_snapshot(
1512 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1515 assert(stream
->ustream
);
1518 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
1522 * Called when the stream signal the consumer that it has hang up.
1524 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1527 assert(stream
->ustream
);
1529 ustctl_flush_buffer(stream
->ustream
, 0);
1530 stream
->hangup_flush_done
= 1;
1533 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1536 assert(chan
->uchan
);
1538 if (chan
->switch_timer_enabled
== 1) {
1539 consumer_timer_switch_stop(chan
);
1541 consumer_metadata_cache_destroy(chan
);
1542 ustctl_destroy_channel(chan
->uchan
);
1545 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
1548 assert(stream
->ustream
);
1550 if (stream
->chan
->switch_timer_enabled
== 1) {
1551 consumer_timer_switch_stop(stream
->chan
);
1553 ustctl_destroy_stream(stream
->ustream
);
1556 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
1557 struct lttng_consumer_local_data
*ctx
)
1559 unsigned long len
, subbuf_size
, padding
;
1563 struct ustctl_consumer_stream
*ustream
;
1566 assert(stream
->ustream
);
1569 DBG("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
1572 /* Ease our life for what's next. */
1573 ustream
= stream
->ustream
;
1575 /* We can consume the 1 byte written into the wait_fd by UST */
1576 if (stream
->monitor
&& !stream
->hangup_flush_done
) {
1580 readlen
= read(stream
->wait_fd
, &dummy
, 1);
1581 } while (readlen
== -1 && errno
== EINTR
);
1582 if (readlen
== -1 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
1589 /* Get the next subbuffer */
1590 err
= ustctl_get_next_subbuf(ustream
);
1593 * Populate metadata info if the existing info has
1594 * already been read.
1596 if (stream
->metadata_flag
) {
1599 if (stream
->chan
->metadata_cache
->contiguous
1600 == stream
->ust_metadata_pushed
) {
1605 write_len
= ustctl_write_one_packet_to_channel(stream
->chan
->uchan
,
1606 &stream
->chan
->metadata_cache
->data
[stream
->ust_metadata_pushed
],
1607 stream
->chan
->metadata_cache
->contiguous
1608 - stream
->ust_metadata_pushed
);
1609 assert(write_len
!= 0);
1610 if (write_len
< 0) {
1611 ERR("Writing one metadata packet");
1615 stream
->ust_metadata_pushed
+= write_len
;
1616 ustctl_flush_buffer(stream
->ustream
, 1);
1620 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
1622 * This is a debug message even for single-threaded consumer,
1623 * because poll() have more relaxed criterions than get subbuf,
1624 * so get_subbuf may fail for short race windows where poll()
1625 * would issue wakeups.
1627 DBG("Reserving sub buffer failed (everything is normal, "
1628 "it is due to concurrency) [ret: %d]", err
);
1631 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
1632 /* Get the full padded subbuffer size */
1633 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
1636 /* Get subbuffer data size (without padding) */
1637 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
1640 /* Make sure we don't get a subbuffer size bigger than the padded */
1641 assert(len
>= subbuf_size
);
1643 padding
= len
- subbuf_size
;
1644 /* write the subbuffer to the tracefile */
1645 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
);
1647 * The mmap operation should write subbuf_size amount of data when network
1648 * streaming or the full padding (len) size when we are _not_ streaming.
1650 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
1651 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
1653 * Display the error but continue processing to try to release the
1654 * subbuffer. This is a DBG statement since any unexpected kill or
1655 * signal, the application gets unregistered, relayd gets closed or
1656 * anything that affects the buffer lifetime will trigger this error.
1657 * So, for the sake of the user, don't print this error since it can
1658 * happen and it is OK with the code flow.
1660 DBG("Error writing to tracefile "
1661 "(ret: %ld != len: %lu != subbuf_size: %lu)",
1662 ret
, len
, subbuf_size
);
1664 err
= ustctl_put_next_subbuf(ustream
);
1672 * Called when a stream is created.
1674 * Return 0 on success or else a negative value.
1676 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
1682 /* Don't create anything if this is set for streaming. */
1683 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
) {
1684 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
1685 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
1686 stream
->uid
, stream
->gid
);
1690 stream
->out_fd
= ret
;
1691 stream
->tracefile_size_current
= 0;
1700 * Check if data is still being extracted from the buffers for a specific
1701 * stream. Consumer data lock MUST be acquired before calling this function
1702 * and the stream lock.
1704 * Return 1 if the traced data are still getting read else 0 meaning that the
1705 * data is available for trace viewer reading.
1707 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
1712 assert(stream
->ustream
);
1714 DBG("UST consumer checking data pending");
1716 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
1721 if (stream
->chan
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
1723 * We can simply check whether all contiguously available data
1724 * has been pushed to the ring buffer, since the push operation
1725 * is performed within get_next_subbuf(), and because both
1726 * get_next_subbuf() and put_next_subbuf() are issued atomically
1727 * thanks to the stream lock within
1728 * lttng_ustconsumer_read_subbuffer(). This basically means that
1729 * whetnever ust_metadata_pushed is incremented, the associated
1730 * metadata has been consumed from the metadata stream.
1732 DBG("UST consumer metadata pending check: contiguous %" PRIu64
" vs pushed %" PRIu64
,
1733 stream
->chan
->metadata_cache
->contiguous
,
1734 stream
->ust_metadata_pushed
);
1735 if (stream
->chan
->metadata_cache
->contiguous
1736 != stream
->ust_metadata_pushed
) {
1737 ret
= 1; /* Data is pending */
1741 ret
= ustctl_get_next_subbuf(stream
->ustream
);
1744 * There is still data so let's put back this
1747 ret
= ustctl_put_subbuf(stream
->ustream
);
1749 ret
= 1; /* Data is pending */
1754 /* Data is NOT pending so ready to be read. */
1762 * Close every metadata stream wait fd of the metadata hash table. This
1763 * function MUST be used very carefully so not to run into a race between the
1764 * metadata thread handling streams and this function closing their wait fd.
1766 * For UST, this is used when the session daemon hangs up. Its the metadata
1767 * producer so calling this is safe because we are assured that no state change
1768 * can occur in the metadata thread for the streams in the hash table.
1770 void lttng_ustconsumer_close_metadata(struct lttng_ht
*metadata_ht
)
1773 struct lttng_ht_iter iter
;
1774 struct lttng_consumer_stream
*stream
;
1776 assert(metadata_ht
);
1777 assert(metadata_ht
->ht
);
1779 DBG("UST consumer closing all metadata streams");
1782 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
1784 int fd
= stream
->wait_fd
;
1787 * Whatever happens here we have to continue to try to close every
1788 * streams. Let's report at least the error on failure.
1790 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
1792 ERR("Unable to close metadata stream fd %d ret %d", fd
, ret
);
1794 DBG("Metadata wait fd %d closed", fd
);
1799 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
1803 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
1805 ERR("Unable to close wakeup fd");
1810 * Please refer to consumer-timer.c before adding any lock within this
1811 * function or any of its callees. Timers have a very strict locking
1812 * semantic with respect to teardown. Failure to respect this semantic
1813 * introduces deadlocks.
1815 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
1816 struct lttng_consumer_channel
*channel
)
1818 struct lttcomm_metadata_request_msg request
;
1819 struct lttcomm_consumer_msg msg
;
1820 enum lttng_error_code ret_code
= LTTNG_OK
;
1821 uint64_t len
, key
, offset
;
1825 assert(channel
->metadata_cache
);
1827 /* send the metadata request to sessiond */
1828 switch (consumer_data
.type
) {
1829 case LTTNG_CONSUMER64_UST
:
1830 request
.bits_per_long
= 64;
1832 case LTTNG_CONSUMER32_UST
:
1833 request
.bits_per_long
= 32;
1836 request
.bits_per_long
= 0;
1840 request
.session_id
= channel
->session_id
;
1841 request
.session_id_per_pid
= channel
->session_id_per_pid
;
1842 request
.uid
= channel
->uid
;
1843 request
.key
= channel
->key
;
1844 DBG("Sending metadata request to sessiond, session id %" PRIu64
1845 ", per-pid %" PRIu64
,
1846 channel
->session_id
,
1847 channel
->session_id_per_pid
);
1849 pthread_mutex_lock(&ctx
->metadata_socket_lock
);
1850 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
1853 ERR("Asking metadata to sessiond");
1857 /* Receive the metadata from sessiond */
1858 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
1860 if (ret
!= sizeof(msg
)) {
1861 DBG("Consumer received unexpected message size %d (expects %zu)",
1863 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1865 * The ret value might 0 meaning an orderly shutdown but this is ok
1866 * since the caller handles this.
1871 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
1872 /* No registry found */
1873 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
1877 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
1878 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
1883 len
= msg
.u
.push_metadata
.len
;
1884 key
= msg
.u
.push_metadata
.key
;
1885 offset
= msg
.u
.push_metadata
.target_offset
;
1887 assert(key
== channel
->key
);
1889 DBG("No new metadata to receive for key %" PRIu64
, key
);
1892 /* Tell session daemon we are ready to receive the metadata. */
1893 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
1895 if (ret
< 0 || len
== 0) {
1897 * Somehow, the session daemon is not responding anymore or there is
1898 * nothing to receive.
1903 ret_code
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
1904 key
, offset
, len
, channel
);
1905 if (ret_code
>= 0) {
1907 * Only send the status msg if the sessiond is alive meaning a positive
1910 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret_code
);
1915 pthread_mutex_unlock(&ctx
->metadata_socket_lock
);