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 * Search for a relayd object related to the stream. If found, send the stream
216 * On success, returns 0 else a negative value.
218 static int send_stream_to_relayd(struct lttng_consumer_stream
*stream
)
221 struct consumer_relayd_sock_pair
*relayd
;
225 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
226 if (relayd
!= NULL
) {
227 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
228 /* Add stream on the relayd */
229 ret
= relayd_add_stream(&relayd
->control_sock
, stream
->name
,
230 stream
->chan
->pathname
, &stream
->relayd_stream_id
,
231 stream
->chan
->tracefile_size
,
232 stream
->chan
->tracefile_count
);
233 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
237 } else if (stream
->net_seq_idx
!= (uint64_t) -1ULL) {
238 ERR("Network sequence index %" PRIu64
" unknown. Not adding stream.",
239 stream
->net_seq_idx
);
249 * Create streams for the given channel using liblttng-ust-ctl.
251 * Return 0 on success else a negative value.
253 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
254 struct lttng_consumer_local_data
*ctx
)
257 struct ustctl_consumer_stream
*ustream
;
258 struct lttng_consumer_stream
*stream
;
264 * While a stream is available from ustctl. When NULL is returned, we've
265 * reached the end of the possible stream for the channel.
267 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
270 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
272 /* Allocate consumer stream object. */
273 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
277 stream
->ustream
= ustream
;
279 * Store it so we can save multiple function calls afterwards since
280 * this value is used heavily in the stream threads. This is UST
281 * specific so this is why it's done after allocation.
283 stream
->wait_fd
= wait_fd
;
286 * Increment channel refcount since the channel reference has now been
287 * assigned in the allocation process above.
289 if (stream
->chan
->monitor
) {
290 uatomic_inc(&stream
->chan
->refcount
);
294 * Order is important this is why a list is used. On error, the caller
295 * should clean this list.
297 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
299 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
300 &stream
->max_sb_size
);
302 ERR("ustctl_get_max_subbuf_size failed for stream %s",
307 /* Do actions once stream has been received. */
308 if (ctx
->on_recv_stream
) {
309 ret
= ctx
->on_recv_stream(stream
);
315 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
316 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
318 /* Set next CPU stream. */
319 channel
->streams
.count
= ++cpu
;
321 /* Keep stream reference when creating metadata. */
322 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
323 channel
->metadata_stream
= stream
;
335 * Create an UST channel with the given attributes and send it to the session
336 * daemon using the ust ctl API.
338 * Return 0 on success or else a negative value.
340 static int create_ust_channel(struct ustctl_consumer_channel_attr
*attr
,
341 struct ustctl_consumer_channel
**chanp
)
344 struct ustctl_consumer_channel
*channel
;
349 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
350 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
351 "switch_timer_interval: %u, read_timer_interval: %u, "
352 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
353 attr
->num_subbuf
, attr
->switch_timer_interval
,
354 attr
->read_timer_interval
, attr
->output
, attr
->type
);
356 channel
= ustctl_create_channel(attr
);
371 * Send a single given stream to the session daemon using the sock.
373 * Return 0 on success else a negative value.
375 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
382 DBG2("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
384 /* Send stream to session daemon. */
385 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
395 * Send channel to sessiond.
397 * Return 0 on success or else a negative value.
399 static int send_sessiond_channel(int sock
,
400 struct lttng_consumer_channel
*channel
,
401 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
403 int ret
, ret_code
= LTTNG_OK
;
404 struct lttng_consumer_stream
*stream
;
410 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
412 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
413 /* Try to send the stream to the relayd if one is available. */
414 ret
= send_stream_to_relayd(stream
);
417 * Flag that the relayd was the problem here probably due to a
418 * communicaton error on the socket.
423 ret_code
= LTTNG_ERR_RELAYD_CONNECT_FAIL
;
427 /* Inform sessiond that we are about to send channel and streams. */
428 ret
= consumer_send_status_msg(sock
, ret_code
);
429 if (ret
< 0 || ret_code
!= LTTNG_OK
) {
431 * Either the session daemon is not responding or the relayd died so we
437 /* Send channel to sessiond. */
438 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
443 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
448 /* The channel was sent successfully to the sessiond at this point. */
449 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
450 /* Send stream to session daemon. */
451 ret
= send_sessiond_stream(sock
, stream
);
457 /* Tell sessiond there is no more stream. */
458 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
463 DBG("UST consumer NULL stream sent to sessiond");
468 if (ret_code
!= LTTNG_OK
) {
475 * Creates a channel and streams and add the channel it to the channel internal
476 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
479 * Return 0 on success or else, a negative value is returned and the channel
480 * MUST be destroyed by consumer_del_channel().
482 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
483 struct lttng_consumer_channel
*channel
,
484 struct ustctl_consumer_channel_attr
*attr
)
493 * This value is still used by the kernel consumer since for the kernel,
494 * the stream ownership is not IN the consumer so we need to have the
495 * number of left stream that needs to be initialized so we can know when
496 * to delete the channel (see consumer.c).
498 * As for the user space tracer now, the consumer creates and sends the
499 * stream to the session daemon which only sends them to the application
500 * once every stream of a channel is received making this value useless
501 * because we they will be added to the poll thread before the application
502 * receives them. This ensures that a stream can not hang up during
503 * initilization of a channel.
505 channel
->nb_init_stream_left
= 0;
507 /* The reply msg status is handled in the following call. */
508 ret
= create_ust_channel(attr
, &channel
->uchan
);
513 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
516 * For the snapshots (no monitor), we create the metadata streams
517 * on demand, not during the channel creation.
519 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& !channel
->monitor
) {
524 /* Open all streams for this channel. */
525 ret
= create_ust_streams(channel
, ctx
);
535 * Send all stream of a channel to the right thread handling it.
537 * On error, return a negative value else 0 on success.
539 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
540 struct lttng_consumer_local_data
*ctx
)
543 struct lttng_consumer_stream
*stream
, *stmp
;
548 /* Send streams to the corresponding thread. */
549 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
551 /* Sending the stream to the thread. */
552 ret
= send_stream_to_thread(stream
, ctx
);
555 * If we are unable to send the stream to the thread, there is
556 * a big problem so just stop everything.
561 /* Remove node from the channel stream list. */
562 cds_list_del(&stream
->send_node
);
565 * From this point on, the stream's ownership has been moved away from
566 * the channel and becomes globally visible.
568 stream
->globally_visible
= 1;
576 * Write metadata to the given channel using ustctl to convert the string to
578 * Called only from consumer_metadata_cache_write.
579 * The metadata cache lock MUST be acquired to write in the cache.
581 * Return 0 on success else a negative value.
583 int lttng_ustconsumer_push_metadata(struct lttng_consumer_channel
*metadata
,
584 const char *metadata_str
, uint64_t target_offset
, uint64_t len
)
589 assert(metadata_str
);
591 DBG("UST consumer writing metadata to channel %s", metadata
->name
);
593 if (!metadata
->metadata_stream
) {
598 assert(target_offset
<= metadata
->metadata_cache
->max_offset
);
599 ret
= ustctl_write_metadata_to_channel(metadata
->uchan
,
600 metadata_str
+ target_offset
, len
);
602 ERR("ustctl write metadata fail with ret %d, len %" PRIu64
, ret
, len
);
606 ustctl_flush_buffer(metadata
->metadata_stream
->ustream
, 1);
613 * Flush channel's streams using the given key to retrieve the channel.
615 * Return 0 on success else an LTTng error code.
617 static int flush_channel(uint64_t chan_key
)
620 struct lttng_consumer_channel
*channel
;
621 struct lttng_consumer_stream
*stream
;
623 struct lttng_ht_iter iter
;
625 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
628 channel
= consumer_find_channel(chan_key
);
630 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
631 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
635 ht
= consumer_data
.stream_per_chan_id_ht
;
637 /* For each stream of the channel id, flush it. */
638 cds_lfht_for_each_entry_duplicate(ht
->ht
,
639 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
640 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
641 ustctl_flush_buffer(stream
->ustream
, 1);
649 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
650 * RCU read side lock MUST be acquired before calling this function.
652 * Return 0 on success else an LTTng error code.
654 static int close_metadata(uint64_t chan_key
)
657 struct lttng_consumer_channel
*channel
;
659 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
661 channel
= consumer_find_channel(chan_key
);
664 * This is possible if the metadata thread has issue a delete because
665 * the endpoint point of the stream hung up. There is no way the
666 * session daemon can know about it thus use a DBG instead of an actual
669 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
670 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
674 pthread_mutex_lock(&consumer_data
.lock
);
676 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
680 if (channel
->switch_timer_enabled
== 1) {
681 DBG("Deleting timer on metadata channel");
682 consumer_timer_switch_stop(channel
);
685 if (channel
->metadata_stream
) {
686 ret
= ustctl_stream_close_wakeup_fd(channel
->metadata_stream
->ustream
);
688 ERR("UST consumer unable to close fd of metadata (ret: %d)", ret
);
689 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
695 pthread_mutex_unlock(&consumer_data
.lock
);
701 * RCU read side lock MUST be acquired before calling this function.
703 * Return 0 on success else an LTTng error code.
705 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
708 struct lttng_consumer_channel
*metadata
;
710 DBG("UST consumer setup metadata key %" PRIu64
, key
);
712 metadata
= consumer_find_channel(key
);
714 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
715 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
720 * In no monitor mode, the metadata channel has no stream(s) so skip the
721 * ownership transfer to the metadata thread.
723 if (!metadata
->monitor
) {
724 DBG("Metadata channel in no monitor");
730 * Send metadata stream to relayd if one available. Availability is
731 * known if the stream is still in the list of the channel.
733 if (cds_list_empty(&metadata
->streams
.head
)) {
734 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
735 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
736 goto error_no_stream
;
739 /* Send metadata stream to relayd if needed. */
740 ret
= send_stream_to_relayd(metadata
->metadata_stream
);
742 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
746 ret
= send_streams_to_thread(metadata
, ctx
);
749 * If we are unable to send the stream to the thread, there is
750 * a big problem so just stop everything.
752 ret
= LTTCOMM_CONSUMERD_FATAL
;
755 /* List MUST be empty after or else it could be reused. */
756 assert(cds_list_empty(&metadata
->streams
.head
));
763 * Delete metadata channel on error. At this point, the metadata stream can
764 * NOT be monitored by the metadata thread thus having the guarantee that
765 * the stream is still in the local stream list of the channel. This call
766 * will make sure to clean that list.
768 cds_list_del(&metadata
->metadata_stream
->send_node
);
769 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
776 * Snapshot the whole metadata.
778 * Returns 0 on success, < 0 on error
780 static int snapshot_metadata(uint64_t key
, char *path
, uint64_t relayd_id
,
781 struct lttng_consumer_local_data
*ctx
)
785 uint64_t total_len
= 0;
786 struct lttng_consumer_channel
*metadata_channel
;
787 struct lttng_consumer_stream
*metadata_stream
;
792 DBG("UST consumer snapshot metadata with key %" PRIu64
" at path %s",
797 metadata_channel
= consumer_find_channel(key
);
798 if (!metadata_channel
) {
799 ERR("UST snapshot metadata channel not found for key %lu", key
);
803 assert(!metadata_channel
->monitor
);
806 * Ask the sessiond if we have new metadata waiting and update the
807 * consumer metadata cache.
809 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
);
815 * The metadata stream is NOT created in no monitor mode when the channel
816 * is created on a sessiond ask channel command.
818 ret
= create_ust_streams(metadata_channel
, ctx
);
823 metadata_stream
= metadata_channel
->metadata_stream
;
824 assert(metadata_stream
);
826 if (relayd_id
!= (uint64_t) -1ULL) {
827 metadata_stream
->net_seq_idx
= relayd_id
;
828 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
833 ret
= utils_create_stream_file(path
, metadata_stream
->name
,
834 metadata_stream
->chan
->tracefile_size
,
835 metadata_stream
->tracefile_count_current
,
836 metadata_stream
->uid
, metadata_stream
->gid
);
840 metadata_stream
->out_fd
= ret
;
841 metadata_stream
->tracefile_size_current
= 0;
844 pthread_mutex_lock(&metadata_channel
->metadata_cache
->lock
);
845 while (total_len
< metadata_channel
->metadata_cache
->total_bytes_written
) {
847 * Write at most one packet of metadata into the channel
848 * to avoid blocking here.
850 write_len
= ustctl_write_one_packet_to_channel(metadata_channel
->uchan
,
851 metadata_channel
->metadata_cache
->data
,
852 metadata_channel
->metadata_cache
->total_bytes_written
);
854 ERR("UST consumer snapshot writing metadata packet");
858 total_len
+= write_len
;
860 DBG("Written %" PRIu64
" bytes to metadata (left: %" PRIu64
")",
862 metadata_channel
->metadata_cache
->total_bytes_written
- write_len
);
863 ustctl_flush_buffer(metadata_stream
->ustream
, 1);
864 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
);
871 pthread_mutex_unlock(&metadata_channel
->metadata_cache
->lock
);
875 * Clean up the stream completly because the next snapshot will use a new
878 cds_list_del(&metadata_stream
->send_node
);
879 consumer_stream_destroy(metadata_stream
, NULL
);
880 metadata_channel
->metadata_stream
= NULL
;
888 * Take a snapshot of all the stream of a channel.
890 * Returns 0 on success, < 0 on error
892 static int snapshot_channel(uint64_t key
, char *path
, uint64_t relayd_id
,
893 struct lttng_consumer_local_data
*ctx
)
896 unsigned use_relayd
= 0;
897 unsigned long consumed_pos
, produced_pos
;
898 struct lttng_consumer_channel
*channel
;
899 struct lttng_consumer_stream
*stream
;
906 if (relayd_id
!= (uint64_t) -1ULL) {
910 channel
= consumer_find_channel(key
);
912 ERR("UST snapshot channel not found for key %lu", key
);
916 assert(!channel
->monitor
);
917 DBG("UST consumer snapshot channel %lu", key
);
919 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
920 /* Lock stream because we are about to change its state. */
921 pthread_mutex_lock(&stream
->lock
);
922 stream
->net_seq_idx
= relayd_id
;
925 ret
= consumer_send_relayd_stream(stream
, path
);
930 ret
= utils_create_stream_file(path
, stream
->name
,
931 stream
->chan
->tracefile_size
,
932 stream
->tracefile_count_current
,
933 stream
->uid
, stream
->gid
);
937 stream
->out_fd
= ret
;
938 stream
->tracefile_size_current
= 0;
940 DBG("UST consumer snapshot stream %s/%s (%" PRIu64
")", path
,
941 stream
->name
, stream
->key
);
944 ustctl_flush_buffer(stream
->ustream
, 1);
946 ret
= lttng_ustconsumer_take_snapshot(stream
);
948 ERR("Taking UST snapshot");
952 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
954 ERR("Produced UST snapshot position");
958 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
960 ERR("Consumerd UST snapshot position");
964 while (consumed_pos
< produced_pos
) {
966 unsigned long len
, padded_len
;
968 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
970 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
972 if (ret
!= -EAGAIN
) {
973 PERROR("ustctl_get_subbuf snapshot");
974 goto error_close_stream
;
976 DBG("UST consumer get subbuf failed. Skipping it.");
977 consumed_pos
+= stream
->max_sb_size
;
981 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
983 ERR("Snapshot ustctl_get_subbuf_size");
984 goto error_put_subbuf
;
987 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
989 ERR("Snapshot ustctl_get_padded_subbuf_size");
990 goto error_put_subbuf
;
993 read_len
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, len
,
996 if (read_len
!= len
) {
998 goto error_put_subbuf
;
1001 if (read_len
!= padded_len
) {
1003 goto error_put_subbuf
;
1007 ret
= ustctl_put_subbuf(stream
->ustream
);
1009 ERR("Snapshot ustctl_put_subbuf");
1010 goto error_close_stream
;
1012 consumed_pos
+= stream
->max_sb_size
;
1015 /* Simply close the stream so we can use it on the next snapshot. */
1016 consumer_stream_close(stream
);
1017 pthread_mutex_unlock(&stream
->lock
);
1024 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
1025 ERR("Snapshot ustctl_put_subbuf");
1028 consumer_stream_close(stream
);
1030 pthread_mutex_unlock(&stream
->lock
);
1037 * Receive the metadata updates from the sessiond.
1039 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
1040 uint64_t len
, struct lttng_consumer_channel
*channel
)
1042 int ret
, ret_code
= LTTNG_OK
;
1045 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
1047 metadata_str
= zmalloc(len
* sizeof(char));
1048 if (!metadata_str
) {
1049 PERROR("zmalloc metadata string");
1050 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
1054 /* Receive metadata string. */
1055 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1057 /* Session daemon is dead so return gracefully. */
1063 * XXX: The consumer data lock is acquired before calling metadata cache
1064 * write which calls push metadata that MUST be protected by the consumer
1065 * lock in order to be able to check the validity of the metadata stream of
1068 * Note that this will be subject to change to better fine grained locking
1069 * and ultimately try to get rid of this global consumer data lock.
1071 pthread_mutex_lock(&consumer_data
.lock
);
1073 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1074 ret
= consumer_metadata_cache_write(channel
, offset
, len
, metadata_str
);
1076 /* Unable to handle metadata. Notify session daemon. */
1077 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1079 * Skip metadata flush on write error since the offset and len might
1080 * not have been updated which could create an infinite loop below when
1081 * waiting for the metadata cache to be flushed.
1083 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1084 pthread_mutex_unlock(&consumer_data
.lock
);
1087 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1088 pthread_mutex_unlock(&consumer_data
.lock
);
1090 while (consumer_metadata_cache_flushed(channel
, offset
+ len
)) {
1091 DBG("Waiting for metadata to be flushed");
1092 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1102 * Receive command from session daemon and process it.
1104 * Return 1 on success else a negative value or 0.
1106 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1107 int sock
, struct pollfd
*consumer_sockpoll
)
1110 enum lttng_error_code ret_code
= LTTNG_OK
;
1111 struct lttcomm_consumer_msg msg
;
1112 struct lttng_consumer_channel
*channel
= NULL
;
1114 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1115 if (ret
!= sizeof(msg
)) {
1116 DBG("Consumer received unexpected message size %zd (expects %zu)",
1118 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1120 * The ret value might 0 meaning an orderly shutdown but this is ok
1121 * since the caller handles this.
1128 if (msg
.cmd_type
== LTTNG_CONSUMER_STOP
) {
1130 * Notify the session daemon that the command is completed.
1132 * On transport layer error, the function call will print an error
1133 * message so handling the returned code is a bit useless since we
1134 * return an error code anyway.
1136 (void) consumer_send_status_msg(sock
, ret_code
);
1140 /* relayd needs RCU read-side lock */
1143 switch (msg
.cmd_type
) {
1144 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1146 /* Session daemon status message are handled in the following call. */
1147 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1148 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1149 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
);
1152 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1154 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1155 struct consumer_relayd_sock_pair
*relayd
;
1157 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1159 /* Get relayd reference if exists. */
1160 relayd
= consumer_find_relayd(index
);
1161 if (relayd
== NULL
) {
1162 DBG("Unable to find relayd %" PRIu64
, index
);
1163 ret_code
= LTTNG_ERR_NO_CONSUMER
;
1167 * Each relayd socket pair has a refcount of stream attached to it
1168 * which tells if the relayd is still active or not depending on the
1171 * This will set the destroy flag of the relayd object and destroy it
1172 * if the refcount reaches zero when called.
1174 * The destroy can happen either here or when a stream fd hangs up.
1177 consumer_flag_relayd_for_destroy(relayd
);
1180 goto end_msg_sessiond
;
1182 case LTTNG_CONSUMER_UPDATE_STREAM
:
1187 case LTTNG_CONSUMER_DATA_PENDING
:
1189 int ret
, is_data_pending
;
1190 uint64_t id
= msg
.u
.data_pending
.session_id
;
1192 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1194 is_data_pending
= consumer_data_pending(id
);
1196 /* Send back returned value to session daemon */
1197 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1198 sizeof(is_data_pending
));
1200 DBG("Error when sending the data pending ret code: %d", ret
);
1205 * No need to send back a status message since the data pending
1206 * returned value is the response.
1210 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1213 struct ustctl_consumer_channel_attr attr
;
1215 /* Create a plain object and reserve a channel key. */
1216 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
1217 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
1218 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
1219 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
1220 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1221 msg
.u
.ask_channel
.tracefile_size
,
1222 msg
.u
.ask_channel
.tracefile_count
,
1223 msg
.u
.ask_channel
.session_id_per_pid
,
1224 msg
.u
.ask_channel
.monitor
);
1226 goto end_channel_error
;
1229 /* Build channel attributes from received message. */
1230 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1231 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1232 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1233 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1234 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1235 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1236 attr
.output
= msg
.u
.ask_channel
.output
;
1237 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1239 /* Translate and save channel type. */
1240 switch (msg
.u
.ask_channel
.type
) {
1241 case LTTNG_UST_CHAN_PER_CPU
:
1242 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1243 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1245 * Set refcount to 1 for owner. Below, we will
1246 * pass ownership to the
1247 * consumer_thread_channel_poll() thread.
1249 channel
->refcount
= 1;
1251 case LTTNG_UST_CHAN_METADATA
:
1252 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1253 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1260 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
1262 goto end_channel_error
;
1265 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1266 ret
= consumer_metadata_cache_allocate(channel
);
1268 ERR("Allocating metadata cache");
1269 goto end_channel_error
;
1271 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1272 attr
.switch_timer_interval
= 0;
1276 * Add the channel to the internal state AFTER all streams were created
1277 * and successfully sent to session daemon. This way, all streams must
1278 * be ready before this channel is visible to the threads.
1279 * If add_channel succeeds, ownership of the channel is
1280 * passed to consumer_thread_channel_poll().
1282 ret
= add_channel(channel
, ctx
);
1284 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1285 if (channel
->switch_timer_enabled
== 1) {
1286 consumer_timer_switch_stop(channel
);
1288 consumer_metadata_cache_destroy(channel
);
1290 goto end_channel_error
;
1294 * Channel and streams are now created. Inform the session daemon that
1295 * everything went well and should wait to receive the channel and
1296 * streams with ustctl API.
1298 ret
= consumer_send_status_channel(sock
, channel
);
1301 * There is probably a problem on the socket.
1308 case LTTNG_CONSUMER_GET_CHANNEL
:
1310 int ret
, relayd_err
= 0;
1311 uint64_t key
= msg
.u
.get_channel
.key
;
1312 struct lttng_consumer_channel
*channel
;
1314 channel
= consumer_find_channel(key
);
1316 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1317 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
1318 goto end_msg_sessiond
;
1321 /* Send everything to sessiond. */
1322 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1326 * We were unable to send to the relayd the stream so avoid
1327 * sending back a fatal error to the thread since this is OK
1328 * and the consumer can continue its work. The above call
1329 * has sent the error status message to the sessiond.
1334 * The communicaton was broken hence there is a bad state between
1335 * the consumer and sessiond so stop everything.
1341 * In no monitor mode, the streams ownership is kept inside the channel
1342 * so don't send them to the data thread.
1344 if (!channel
->monitor
) {
1345 goto end_msg_sessiond
;
1348 ret
= send_streams_to_thread(channel
, ctx
);
1351 * If we are unable to send the stream to the thread, there is
1352 * a big problem so just stop everything.
1356 /* List MUST be empty after or else it could be reused. */
1357 assert(cds_list_empty(&channel
->streams
.head
));
1358 goto end_msg_sessiond
;
1360 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1362 uint64_t key
= msg
.u
.destroy_channel
.key
;
1365 * Only called if streams have not been sent to stream
1366 * manager thread. However, channel has been sent to
1367 * channel manager thread.
1369 notify_thread_del_channel(ctx
, key
);
1370 goto end_msg_sessiond
;
1372 case LTTNG_CONSUMER_CLOSE_METADATA
:
1376 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1381 goto end_msg_sessiond
;
1383 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1387 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1392 goto end_msg_sessiond
;
1394 case LTTNG_CONSUMER_PUSH_METADATA
:
1397 uint64_t len
= msg
.u
.push_metadata
.len
;
1398 uint64_t key
= msg
.u
.push_metadata
.key
;
1399 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1400 struct lttng_consumer_channel
*channel
;
1402 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1405 channel
= consumer_find_channel(key
);
1407 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
1408 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
1409 goto end_msg_sessiond
;
1412 /* Tell session daemon we are ready to receive the metadata. */
1413 ret
= consumer_send_status_msg(sock
, LTTNG_OK
);
1415 /* Somehow, the session daemon is not responding anymore. */
1419 /* Wait for more data. */
1420 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
1424 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1427 /* error receiving from sessiond */
1431 goto end_msg_sessiond
;
1434 case LTTNG_CONSUMER_SETUP_METADATA
:
1438 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1442 goto end_msg_sessiond
;
1444 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1446 if (msg
.u
.snapshot_channel
.metadata
) {
1447 ret
= snapshot_metadata(msg
.u
.snapshot_channel
.key
,
1448 msg
.u
.snapshot_channel
.pathname
,
1449 msg
.u
.snapshot_channel
.relayd_id
,
1452 ERR("Snapshot metadata failed");
1453 ret_code
= LTTNG_ERR_UST_META_FAIL
;
1456 ret
= snapshot_channel(msg
.u
.snapshot_channel
.key
,
1457 msg
.u
.snapshot_channel
.pathname
,
1458 msg
.u
.snapshot_channel
.relayd_id
,
1461 ERR("Snapshot channel failed");
1462 ret_code
= LTTNG_ERR_UST_CHAN_FAIL
;
1466 ret
= consumer_send_status_msg(sock
, ret_code
);
1468 /* Somehow, the session daemon is not responding anymore. */
1481 * Return 1 to indicate success since the 0 value can be a socket
1482 * shutdown during the recv() or send() call.
1488 * The returned value here is not useful since either way we'll return 1 to
1489 * the caller because the session daemon socket management is done
1490 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1492 ret
= consumer_send_status_msg(sock
, ret_code
);
1501 * Free channel here since no one has a reference to it. We don't
1502 * free after that because a stream can store this pointer.
1504 destroy_channel(channel
);
1506 /* We have to send a status channel message indicating an error. */
1507 ret
= consumer_send_status_channel(sock
, NULL
);
1509 /* Stop everything if session daemon can not be notified. */
1516 /* This will issue a consumer stop. */
1521 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1522 * compiled out, we isolate it in this library.
1524 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1528 assert(stream
->ustream
);
1530 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1534 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1535 * compiled out, we isolate it in this library.
1537 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1540 assert(stream
->ustream
);
1542 return ustctl_get_mmap_base(stream
->ustream
);
1546 * Take a snapshot for a specific fd
1548 * Returns 0 on success, < 0 on error
1550 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1553 assert(stream
->ustream
);
1555 return ustctl_snapshot(stream
->ustream
);
1559 * Get the produced position
1561 * Returns 0 on success, < 0 on error
1563 int lttng_ustconsumer_get_produced_snapshot(
1564 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1567 assert(stream
->ustream
);
1570 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1574 * Get the consumed position
1576 * Returns 0 on success, < 0 on error
1578 int lttng_ustconsumer_get_consumed_snapshot(
1579 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1582 assert(stream
->ustream
);
1585 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
1589 * Called when the stream signal the consumer that it has hang up.
1591 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1594 assert(stream
->ustream
);
1596 ustctl_flush_buffer(stream
->ustream
, 0);
1597 stream
->hangup_flush_done
= 1;
1600 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1603 assert(chan
->uchan
);
1605 if (chan
->switch_timer_enabled
== 1) {
1606 consumer_timer_switch_stop(chan
);
1608 consumer_metadata_cache_destroy(chan
);
1609 ustctl_destroy_channel(chan
->uchan
);
1612 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
1615 assert(stream
->ustream
);
1617 if (stream
->chan
->switch_timer_enabled
== 1) {
1618 consumer_timer_switch_stop(stream
->chan
);
1620 ustctl_destroy_stream(stream
->ustream
);
1623 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
1624 struct lttng_consumer_local_data
*ctx
)
1626 unsigned long len
, subbuf_size
, padding
;
1630 struct ustctl_consumer_stream
*ustream
;
1633 assert(stream
->ustream
);
1636 DBG2("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
1639 /* Ease our life for what's next. */
1640 ustream
= stream
->ustream
;
1642 /* We can consume the 1 byte written into the wait_fd by UST */
1643 if (!stream
->hangup_flush_done
) {
1647 readlen
= read(stream
->wait_fd
, &dummy
, 1);
1648 } while (readlen
== -1 && errno
== EINTR
);
1649 if (readlen
== -1) {
1655 /* Get the next subbuffer */
1656 err
= ustctl_get_next_subbuf(ustream
);
1658 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
1660 * This is a debug message even for single-threaded consumer,
1661 * because poll() have more relaxed criterions than get subbuf,
1662 * so get_subbuf may fail for short race windows where poll()
1663 * would issue wakeups.
1665 DBG("Reserving sub buffer failed (everything is normal, "
1666 "it is due to concurrency) [ret: %d]", err
);
1669 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
1670 /* Get the full padded subbuffer size */
1671 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
1674 /* Get subbuffer data size (without padding) */
1675 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
1678 /* Make sure we don't get a subbuffer size bigger than the padded */
1679 assert(len
>= subbuf_size
);
1681 padding
= len
- subbuf_size
;
1682 /* write the subbuffer to the tracefile */
1683 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
);
1685 * The mmap operation should write subbuf_size amount of data when network
1686 * streaming or the full padding (len) size when we are _not_ streaming.
1688 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
1689 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
1691 * Display the error but continue processing to try to release the
1692 * subbuffer. This is a DBG statement since any unexpected kill or
1693 * signal, the application gets unregistered, relayd gets closed or
1694 * anything that affects the buffer lifetime will trigger this error.
1695 * So, for the sake of the user, don't print this error since it can
1696 * happen and it is OK with the code flow.
1698 DBG("Error writing to tracefile "
1699 "(ret: %ld != len: %lu != subbuf_size: %lu)",
1700 ret
, len
, subbuf_size
);
1702 err
= ustctl_put_next_subbuf(ustream
);
1710 * Called when a stream is created.
1712 * Return 0 on success or else a negative value.
1714 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
1720 /* Don't create anything if this is set for streaming. */
1721 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
) {
1722 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
1723 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
1724 stream
->uid
, stream
->gid
);
1728 stream
->out_fd
= ret
;
1729 stream
->tracefile_size_current
= 0;
1738 * Check if data is still being extracted from the buffers for a specific
1739 * stream. Consumer data lock MUST be acquired before calling this function
1740 * and the stream lock.
1742 * Return 1 if the traced data are still getting read else 0 meaning that the
1743 * data is available for trace viewer reading.
1745 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
1750 assert(stream
->ustream
);
1752 DBG("UST consumer checking data pending");
1754 ret
= ustctl_get_next_subbuf(stream
->ustream
);
1756 /* There is still data so let's put back this subbuffer. */
1757 ret
= ustctl_put_subbuf(stream
->ustream
);
1759 ret
= 1; /* Data is pending */
1763 /* Data is NOT pending so ready to be read. */
1771 * Close every metadata stream wait fd of the metadata hash table. This
1772 * function MUST be used very carefully so not to run into a race between the
1773 * metadata thread handling streams and this function closing their wait fd.
1775 * For UST, this is used when the session daemon hangs up. Its the metadata
1776 * producer so calling this is safe because we are assured that no state change
1777 * can occur in the metadata thread for the streams in the hash table.
1779 void lttng_ustconsumer_close_metadata(struct lttng_ht
*metadata_ht
)
1782 struct lttng_ht_iter iter
;
1783 struct lttng_consumer_stream
*stream
;
1785 assert(metadata_ht
);
1786 assert(metadata_ht
->ht
);
1788 DBG("UST consumer closing all metadata streams");
1791 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
1793 int fd
= stream
->wait_fd
;
1796 * Whatever happens here we have to continue to try to close every
1797 * streams. Let's report at least the error on failure.
1799 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
1801 ERR("Unable to close metadata stream fd %d ret %d", fd
, ret
);
1803 DBG("Metadata wait fd %d closed", fd
);
1808 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
1812 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
1814 ERR("Unable to close wakeup fd");
1818 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
1819 struct lttng_consumer_channel
*channel
)
1821 struct lttcomm_metadata_request_msg request
;
1822 struct lttcomm_consumer_msg msg
;
1823 enum lttng_error_code ret_code
= LTTNG_OK
;
1824 uint64_t len
, key
, offset
;
1828 assert(channel
->metadata_cache
);
1830 /* send the metadata request to sessiond */
1831 switch (consumer_data
.type
) {
1832 case LTTNG_CONSUMER64_UST
:
1833 request
.bits_per_long
= 64;
1835 case LTTNG_CONSUMER32_UST
:
1836 request
.bits_per_long
= 32;
1839 request
.bits_per_long
= 0;
1843 request
.session_id
= channel
->session_id
;
1844 request
.session_id_per_pid
= channel
->session_id_per_pid
;
1845 request
.uid
= channel
->uid
;
1846 request
.key
= channel
->key
;
1847 DBG("Sending metadata request to sessiond, session id %" PRIu64
1848 ", per-pid %" PRIu64
,
1849 channel
->session_id
,
1850 channel
->session_id_per_pid
);
1852 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
1855 ERR("Asking metadata to sessiond");
1859 /* Receive the metadata from sessiond */
1860 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
1862 if (ret
!= sizeof(msg
)) {
1863 DBG("Consumer received unexpected message size %d (expects %zu)",
1865 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1867 * The ret value might 0 meaning an orderly shutdown but this is ok
1868 * since the caller handles this.
1873 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
1874 /* No registry found */
1875 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
1879 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
1880 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
1885 len
= msg
.u
.push_metadata
.len
;
1886 key
= msg
.u
.push_metadata
.key
;
1887 offset
= msg
.u
.push_metadata
.target_offset
;
1889 assert(key
== channel
->key
);
1891 DBG("No new metadata to receive for key %" PRIu64
, key
);
1894 /* Tell session daemon we are ready to receive the metadata. */
1895 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
1897 if (ret
< 0 || len
== 0) {
1899 * Somehow, the session daemon is not responding anymore or there is
1900 * nothing to receive.
1905 ret_code
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
1906 key
, offset
, len
, channel
);
1907 if (ret_code
>= 0) {
1909 * Only send the status msg if the sessiond is alive meaning a positive
1912 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret_code
);