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 ret
= consumer_add_metadata_stream(stream
);
199 ERR("Consumer add metadata stream %" PRIu64
" failed.",
203 stream_pipe
= ctx
->consumer_metadata_pipe
;
205 ret
= consumer_add_data_stream(stream
);
207 ERR("Consumer add stream %" PRIu64
" failed.",
211 stream_pipe
= ctx
->consumer_data_pipe
;
215 * From this point on, the stream's ownership has been moved away from
216 * the channel and becomes globally visible.
218 stream
->globally_visible
= 1;
220 ret
= lttng_pipe_write(stream_pipe
, &stream
, sizeof(stream
));
222 ERR("Consumer write %s stream to pipe %d",
223 stream
->metadata_flag
? "metadata" : "data",
224 lttng_pipe_get_writefd(stream_pipe
));
225 if (stream
->metadata_flag
) {
226 consumer_del_stream_for_metadata(stream
);
228 consumer_del_stream_for_data(stream
);
236 * Create streams for the given channel using liblttng-ust-ctl.
238 * Return 0 on success else a negative value.
240 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
241 struct lttng_consumer_local_data
*ctx
)
244 struct ustctl_consumer_stream
*ustream
;
245 struct lttng_consumer_stream
*stream
;
251 * While a stream is available from ustctl. When NULL is returned, we've
252 * reached the end of the possible stream for the channel.
254 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
256 int ust_metadata_pipe
[2];
258 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& channel
->monitor
) {
259 ret
= utils_create_pipe_cloexec_nonblock(ust_metadata_pipe
);
261 ERR("Create ust metadata poll pipe");
264 wait_fd
= ust_metadata_pipe
[0];
266 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
269 /* Allocate consumer stream object. */
270 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
274 stream
->ustream
= ustream
;
276 * Store it so we can save multiple function calls afterwards since
277 * this value is used heavily in the stream threads. This is UST
278 * specific so this is why it's done after allocation.
280 stream
->wait_fd
= wait_fd
;
283 * Increment channel refcount since the channel reference has now been
284 * assigned in the allocation process above.
286 if (stream
->chan
->monitor
) {
287 uatomic_inc(&stream
->chan
->refcount
);
291 * Order is important this is why a list is used. On error, the caller
292 * should clean this list.
294 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
296 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
297 &stream
->max_sb_size
);
299 ERR("ustctl_get_max_subbuf_size failed for stream %s",
304 /* Do actions once stream has been received. */
305 if (ctx
->on_recv_stream
) {
306 ret
= ctx
->on_recv_stream(stream
);
312 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
313 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
315 /* Set next CPU stream. */
316 channel
->streams
.count
= ++cpu
;
318 /* Keep stream reference when creating metadata. */
319 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
320 channel
->metadata_stream
= stream
;
321 stream
->ust_metadata_poll_pipe
[0] = ust_metadata_pipe
[0];
322 stream
->ust_metadata_poll_pipe
[1] = ust_metadata_pipe
[1];
334 * Create an UST channel with the given attributes and send it to the session
335 * daemon using the ust ctl API.
337 * Return 0 on success or else a negative value.
339 static int create_ust_channel(struct ustctl_consumer_channel_attr
*attr
,
340 struct ustctl_consumer_channel
**chanp
)
343 struct ustctl_consumer_channel
*channel
;
348 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
349 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
350 "switch_timer_interval: %u, read_timer_interval: %u, "
351 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
352 attr
->num_subbuf
, attr
->switch_timer_interval
,
353 attr
->read_timer_interval
, attr
->output
, attr
->type
);
355 channel
= ustctl_create_channel(attr
);
370 * Send a single given stream to the session daemon using the sock.
372 * Return 0 on success else a negative value.
374 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
381 DBG("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
383 /* Send stream to session daemon. */
384 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
394 * Send channel to sessiond.
396 * Return 0 on success or else a negative value.
398 static int send_sessiond_channel(int sock
,
399 struct lttng_consumer_channel
*channel
,
400 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
402 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
403 struct lttng_consumer_stream
*stream
;
409 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
411 if (channel
->relayd_id
!= (uint64_t) -1ULL) {
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
= consumer_send_relayd_stream(stream
, stream
->chan
->pathname
);
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
;
428 /* Inform sessiond that we are about to send channel and streams. */
429 ret
= consumer_send_status_msg(sock
, ret_code
);
430 if (ret
< 0 || ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
432 * Either the session daemon is not responding or the relayd died so we
438 /* Send channel to sessiond. */
439 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
444 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
449 /* The channel was sent successfully to the sessiond at this point. */
450 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
451 /* Send stream to session daemon. */
452 ret
= send_sessiond_stream(sock
, stream
);
458 /* Tell sessiond there is no more stream. */
459 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
464 DBG("UST consumer NULL stream sent to sessiond");
469 if (ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
476 * Creates a channel and streams and add the channel it to the channel internal
477 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
480 * Return 0 on success or else, a negative value is returned and the channel
481 * MUST be destroyed by consumer_del_channel().
483 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
484 struct lttng_consumer_channel
*channel
,
485 struct ustctl_consumer_channel_attr
*attr
)
494 * This value is still used by the kernel consumer since for the kernel,
495 * the stream ownership is not IN the consumer so we need to have the
496 * number of left stream that needs to be initialized so we can know when
497 * to delete the channel (see consumer.c).
499 * As for the user space tracer now, the consumer creates and sends the
500 * stream to the session daemon which only sends them to the application
501 * once every stream of a channel is received making this value useless
502 * because we they will be added to the poll thread before the application
503 * receives them. This ensures that a stream can not hang up during
504 * initilization of a channel.
506 channel
->nb_init_stream_left
= 0;
508 /* The reply msg status is handled in the following call. */
509 ret
= create_ust_channel(attr
, &channel
->uchan
);
514 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
517 * For the snapshots (no monitor), we create the metadata streams
518 * on demand, not during the channel creation.
520 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& !channel
->monitor
) {
525 /* Open all streams for this channel. */
526 ret
= create_ust_streams(channel
, ctx
);
536 * Send all stream of a channel to the right thread handling it.
538 * On error, return a negative value else 0 on success.
540 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
541 struct lttng_consumer_local_data
*ctx
)
544 struct lttng_consumer_stream
*stream
, *stmp
;
549 /* Send streams to the corresponding thread. */
550 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
552 /* Sending the stream to the thread. */
553 ret
= send_stream_to_thread(stream
, ctx
);
556 * If we are unable to send the stream to the thread, there is
557 * a big problem so just stop everything.
559 /* Remove node from the channel stream list. */
560 cds_list_del(&stream
->send_node
);
564 /* Remove node from the channel stream list. */
565 cds_list_del(&stream
->send_node
);
574 * Flush channel's streams using the given key to retrieve the channel.
576 * Return 0 on success else an LTTng error code.
578 static int flush_channel(uint64_t chan_key
)
581 struct lttng_consumer_channel
*channel
;
582 struct lttng_consumer_stream
*stream
;
584 struct lttng_ht_iter iter
;
586 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
589 channel
= consumer_find_channel(chan_key
);
591 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
592 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
596 ht
= consumer_data
.stream_per_chan_id_ht
;
598 /* For each stream of the channel id, flush it. */
599 cds_lfht_for_each_entry_duplicate(ht
->ht
,
600 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
601 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
602 ustctl_flush_buffer(stream
->ustream
, 1);
609 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
610 * RCU read side lock MUST be acquired before calling this function.
612 * NOTE: This function does NOT take any channel nor stream lock.
614 * Return 0 on success else LTTng error code.
616 static int _close_metadata(struct lttng_consumer_channel
*channel
)
618 int ret
= LTTCOMM_CONSUMERD_SUCCESS
;
621 assert(channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
);
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");
640 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
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
);
675 pthread_mutex_lock(&channel
->lock
);
677 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
681 ret
= _close_metadata(channel
);
684 pthread_mutex_unlock(&channel
->lock
);
685 pthread_mutex_unlock(&consumer_data
.lock
);
691 * RCU read side lock MUST be acquired before calling this function.
693 * Return 0 on success else an LTTng error code.
695 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
698 struct lttng_consumer_channel
*metadata
;
700 DBG("UST consumer setup metadata key %" PRIu64
, key
);
702 metadata
= consumer_find_channel(key
);
704 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
705 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
710 * In no monitor mode, the metadata channel has no stream(s) so skip the
711 * ownership transfer to the metadata thread.
713 if (!metadata
->monitor
) {
714 DBG("Metadata channel in no monitor");
720 * Send metadata stream to relayd if one available. Availability is
721 * known if the stream is still in the list of the channel.
723 if (cds_list_empty(&metadata
->streams
.head
)) {
724 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
725 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
726 goto error_no_stream
;
729 /* Send metadata stream to relayd if needed. */
730 if (metadata
->metadata_stream
->net_seq_idx
!= (uint64_t) -1ULL) {
731 ret
= consumer_send_relayd_stream(metadata
->metadata_stream
,
734 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
739 ret
= send_streams_to_thread(metadata
, ctx
);
742 * If we are unable to send the stream to the thread, there is
743 * a big problem so just stop everything.
745 ret
= LTTCOMM_CONSUMERD_FATAL
;
748 /* List MUST be empty after or else it could be reused. */
749 assert(cds_list_empty(&metadata
->streams
.head
));
756 * Delete metadata channel on error. At this point, the metadata stream can
757 * NOT be monitored by the metadata thread thus having the guarantee that
758 * the stream is still in the local stream list of the channel. This call
759 * will make sure to clean that list.
761 cds_list_del(&metadata
->metadata_stream
->send_node
);
762 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
769 * Snapshot the whole metadata.
771 * Returns 0 on success, < 0 on error
773 static int snapshot_metadata(uint64_t key
, char *path
, uint64_t relayd_id
,
774 struct lttng_consumer_local_data
*ctx
)
777 struct lttng_consumer_channel
*metadata_channel
;
778 struct lttng_consumer_stream
*metadata_stream
;
783 DBG("UST consumer snapshot metadata with key %" PRIu64
" at path %s",
788 metadata_channel
= consumer_find_channel(key
);
789 if (!metadata_channel
) {
790 ERR("UST snapshot metadata channel not found for key %" PRIu64
,
795 assert(!metadata_channel
->monitor
);
798 * Ask the sessiond if we have new metadata waiting and update the
799 * consumer metadata cache.
801 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
, 0);
807 * The metadata stream is NOT created in no monitor mode when the channel
808 * is created on a sessiond ask channel command.
810 ret
= create_ust_streams(metadata_channel
, ctx
);
815 metadata_stream
= metadata_channel
->metadata_stream
;
816 assert(metadata_stream
);
818 if (relayd_id
!= (uint64_t) -1ULL) {
819 metadata_stream
->net_seq_idx
= relayd_id
;
820 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
825 ret
= utils_create_stream_file(path
, metadata_stream
->name
,
826 metadata_stream
->chan
->tracefile_size
,
827 metadata_stream
->tracefile_count_current
,
828 metadata_stream
->uid
, metadata_stream
->gid
);
832 metadata_stream
->out_fd
= ret
;
833 metadata_stream
->tracefile_size_current
= 0;
836 pthread_mutex_lock(&metadata_channel
->metadata_cache
->lock
);
839 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
);
846 pthread_mutex_unlock(&metadata_channel
->metadata_cache
->lock
);
850 * Clean up the stream completly because the next snapshot will use a new
853 cds_list_del(&metadata_stream
->send_node
);
854 consumer_stream_destroy(metadata_stream
, NULL
);
855 metadata_channel
->metadata_stream
= NULL
;
863 * Take a snapshot of all the stream of a channel.
865 * Returns 0 on success, < 0 on error
867 static int snapshot_channel(uint64_t key
, char *path
, uint64_t relayd_id
,
868 uint64_t max_stream_size
, struct lttng_consumer_local_data
*ctx
)
871 unsigned use_relayd
= 0;
872 unsigned long consumed_pos
, produced_pos
;
873 struct lttng_consumer_channel
*channel
;
874 struct lttng_consumer_stream
*stream
;
881 if (relayd_id
!= (uint64_t) -1ULL) {
885 channel
= consumer_find_channel(key
);
887 ERR("UST snapshot channel not found for key %" PRIu64
, key
);
891 assert(!channel
->monitor
);
892 DBG("UST consumer snapshot channel %" PRIu64
, key
);
894 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
895 /* Lock stream because we are about to change its state. */
896 pthread_mutex_lock(&stream
->lock
);
897 stream
->net_seq_idx
= relayd_id
;
900 ret
= consumer_send_relayd_stream(stream
, path
);
905 ret
= utils_create_stream_file(path
, stream
->name
,
906 stream
->chan
->tracefile_size
,
907 stream
->tracefile_count_current
,
908 stream
->uid
, stream
->gid
);
912 stream
->out_fd
= ret
;
913 stream
->tracefile_size_current
= 0;
915 DBG("UST consumer snapshot stream %s/%s (%" PRIu64
")", path
,
916 stream
->name
, stream
->key
);
919 ustctl_flush_buffer(stream
->ustream
, 1);
921 ret
= lttng_ustconsumer_take_snapshot(stream
);
923 ERR("Taking UST snapshot");
927 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
929 ERR("Produced UST snapshot position");
933 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
935 ERR("Consumerd UST snapshot position");
940 * The original value is sent back if max stream size is larger than
941 * the possible size of the snapshot. Also, we asume that the session
942 * daemon should never send a maximum stream size that is lower than
945 consumed_pos
= consumer_get_consumed_maxsize(consumed_pos
,
946 produced_pos
, max_stream_size
);
948 while (consumed_pos
< produced_pos
) {
950 unsigned long len
, padded_len
;
952 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
954 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
956 if (ret
!= -EAGAIN
) {
957 PERROR("ustctl_get_subbuf snapshot");
958 goto error_close_stream
;
960 DBG("UST consumer get subbuf failed. Skipping it.");
961 consumed_pos
+= stream
->max_sb_size
;
965 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
967 ERR("Snapshot ustctl_get_subbuf_size");
968 goto error_put_subbuf
;
971 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
973 ERR("Snapshot ustctl_get_padded_subbuf_size");
974 goto error_put_subbuf
;
977 read_len
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, len
,
980 if (read_len
!= len
) {
982 goto error_put_subbuf
;
985 if (read_len
!= padded_len
) {
987 goto error_put_subbuf
;
991 ret
= ustctl_put_subbuf(stream
->ustream
);
993 ERR("Snapshot ustctl_put_subbuf");
994 goto error_close_stream
;
996 consumed_pos
+= stream
->max_sb_size
;
999 /* Simply close the stream so we can use it on the next snapshot. */
1000 consumer_stream_close(stream
);
1001 pthread_mutex_unlock(&stream
->lock
);
1008 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
1009 ERR("Snapshot ustctl_put_subbuf");
1012 consumer_stream_close(stream
);
1014 pthread_mutex_unlock(&stream
->lock
);
1021 * Receive the metadata updates from the sessiond.
1023 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
1024 uint64_t len
, struct lttng_consumer_channel
*channel
,
1027 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1030 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
1032 metadata_str
= zmalloc(len
* sizeof(char));
1033 if (!metadata_str
) {
1034 PERROR("zmalloc metadata string");
1035 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
1039 /* Receive metadata string. */
1040 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1042 /* Session daemon is dead so return gracefully. */
1047 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1048 ret
= consumer_metadata_cache_write(channel
, offset
, len
, metadata_str
);
1050 /* Unable to handle metadata. Notify session daemon. */
1051 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1053 * Skip metadata flush on write error since the offset and len might
1054 * not have been updated which could create an infinite loop below when
1055 * waiting for the metadata cache to be flushed.
1057 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1060 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1062 while (consumer_metadata_cache_flushed(channel
, offset
+ len
, timer
)) {
1063 DBG("Waiting for metadata to be flushed");
1064 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1074 * Receive command from session daemon and process it.
1076 * Return 1 on success else a negative value or 0.
1078 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1079 int sock
, struct pollfd
*consumer_sockpoll
)
1082 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1083 struct lttcomm_consumer_msg msg
;
1084 struct lttng_consumer_channel
*channel
= NULL
;
1086 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1087 if (ret
!= sizeof(msg
)) {
1088 DBG("Consumer received unexpected message size %zd (expects %zu)",
1091 * The ret value might 0 meaning an orderly shutdown but this is ok
1092 * since the caller handles this.
1095 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1100 if (msg
.cmd_type
== LTTNG_CONSUMER_STOP
) {
1102 * Notify the session daemon that the command is completed.
1104 * On transport layer error, the function call will print an error
1105 * message so handling the returned code is a bit useless since we
1106 * return an error code anyway.
1108 (void) consumer_send_status_msg(sock
, ret_code
);
1112 /* relayd needs RCU read-side lock */
1115 switch (msg
.cmd_type
) {
1116 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1118 /* Session daemon status message are handled in the following call. */
1119 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1120 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1121 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
);
1124 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1126 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1127 struct consumer_relayd_sock_pair
*relayd
;
1129 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1131 /* Get relayd reference if exists. */
1132 relayd
= consumer_find_relayd(index
);
1133 if (relayd
== NULL
) {
1134 DBG("Unable to find relayd %" PRIu64
, index
);
1135 ret_code
= LTTNG_ERR_NO_CONSUMER
;
1139 * Each relayd socket pair has a refcount of stream attached to it
1140 * which tells if the relayd is still active or not depending on the
1143 * This will set the destroy flag of the relayd object and destroy it
1144 * if the refcount reaches zero when called.
1146 * The destroy can happen either here or when a stream fd hangs up.
1149 consumer_flag_relayd_for_destroy(relayd
);
1152 goto end_msg_sessiond
;
1154 case LTTNG_CONSUMER_UPDATE_STREAM
:
1159 case LTTNG_CONSUMER_DATA_PENDING
:
1161 int ret
, is_data_pending
;
1162 uint64_t id
= msg
.u
.data_pending
.session_id
;
1164 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1166 is_data_pending
= consumer_data_pending(id
);
1168 /* Send back returned value to session daemon */
1169 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1170 sizeof(is_data_pending
));
1172 DBG("Error when sending the data pending ret code: %d", ret
);
1177 * No need to send back a status message since the data pending
1178 * returned value is the response.
1182 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1185 struct ustctl_consumer_channel_attr attr
;
1187 /* Create a plain object and reserve a channel key. */
1188 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
1189 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
1190 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
1191 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
1192 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1193 msg
.u
.ask_channel
.tracefile_size
,
1194 msg
.u
.ask_channel
.tracefile_count
,
1195 msg
.u
.ask_channel
.session_id_per_pid
,
1196 msg
.u
.ask_channel
.monitor
);
1198 goto end_channel_error
;
1202 * Assign UST application UID to the channel. This value is ignored for
1203 * per PID buffers. This is specific to UST thus setting this after the
1206 channel
->ust_app_uid
= msg
.u
.ask_channel
.ust_app_uid
;
1208 /* Build channel attributes from received message. */
1209 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1210 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1211 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1212 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1213 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1214 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1215 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1217 /* Match channel buffer type to the UST abi. */
1218 switch (msg
.u
.ask_channel
.output
) {
1219 case LTTNG_EVENT_MMAP
:
1221 attr
.output
= LTTNG_UST_MMAP
;
1225 /* Translate and save channel type. */
1226 switch (msg
.u
.ask_channel
.type
) {
1227 case LTTNG_UST_CHAN_PER_CPU
:
1228 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1229 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1231 * Set refcount to 1 for owner. Below, we will
1232 * pass ownership to the
1233 * consumer_thread_channel_poll() thread.
1235 channel
->refcount
= 1;
1237 case LTTNG_UST_CHAN_METADATA
:
1238 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1239 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1246 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
1248 goto end_channel_error
;
1251 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1252 ret
= consumer_metadata_cache_allocate(channel
);
1254 ERR("Allocating metadata cache");
1255 goto end_channel_error
;
1257 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1258 attr
.switch_timer_interval
= 0;
1262 * Add the channel to the internal state AFTER all streams were created
1263 * and successfully sent to session daemon. This way, all streams must
1264 * be ready before this channel is visible to the threads.
1265 * If add_channel succeeds, ownership of the channel is
1266 * passed to consumer_thread_channel_poll().
1268 ret
= add_channel(channel
, ctx
);
1270 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1271 if (channel
->switch_timer_enabled
== 1) {
1272 consumer_timer_switch_stop(channel
);
1274 consumer_metadata_cache_destroy(channel
);
1276 goto end_channel_error
;
1280 * Channel and streams are now created. Inform the session daemon that
1281 * everything went well and should wait to receive the channel and
1282 * streams with ustctl API.
1284 ret
= consumer_send_status_channel(sock
, channel
);
1287 * There is probably a problem on the socket.
1294 case LTTNG_CONSUMER_GET_CHANNEL
:
1296 int ret
, relayd_err
= 0;
1297 uint64_t key
= msg
.u
.get_channel
.key
;
1298 struct lttng_consumer_channel
*channel
;
1300 channel
= consumer_find_channel(key
);
1302 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1303 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
1304 goto end_msg_sessiond
;
1307 /* Send everything to sessiond. */
1308 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1312 * We were unable to send to the relayd the stream so avoid
1313 * sending back a fatal error to the thread since this is OK
1314 * and the consumer can continue its work. The above call
1315 * has sent the error status message to the sessiond.
1320 * The communicaton was broken hence there is a bad state between
1321 * the consumer and sessiond so stop everything.
1327 * In no monitor mode, the streams ownership is kept inside the channel
1328 * so don't send them to the data thread.
1330 if (!channel
->monitor
) {
1331 goto end_msg_sessiond
;
1334 ret
= send_streams_to_thread(channel
, ctx
);
1337 * If we are unable to send the stream to the thread, there is
1338 * a big problem so just stop everything.
1342 /* List MUST be empty after or else it could be reused. */
1343 assert(cds_list_empty(&channel
->streams
.head
));
1344 goto end_msg_sessiond
;
1346 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1348 uint64_t key
= msg
.u
.destroy_channel
.key
;
1351 * Only called if streams have not been sent to stream
1352 * manager thread. However, channel has been sent to
1353 * channel manager thread.
1355 notify_thread_del_channel(ctx
, key
);
1356 goto end_msg_sessiond
;
1358 case LTTNG_CONSUMER_CLOSE_METADATA
:
1362 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1367 goto end_msg_sessiond
;
1369 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1373 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1378 goto end_msg_sessiond
;
1380 case LTTNG_CONSUMER_PUSH_METADATA
:
1383 uint64_t len
= msg
.u
.push_metadata
.len
;
1384 uint64_t key
= msg
.u
.push_metadata
.key
;
1385 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1386 struct lttng_consumer_channel
*channel
;
1388 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1391 channel
= consumer_find_channel(key
);
1394 * This is possible if the metadata creation on the consumer side
1395 * is in flight vis-a-vis a concurrent push metadata from the
1396 * session daemon. Simply return that the channel failed and the
1397 * session daemon will handle that message correctly considering
1398 * that this race is acceptable thus the DBG() statement here.
1400 DBG("UST consumer push metadata %" PRIu64
" not found", key
);
1401 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1402 goto end_msg_sessiond
;
1405 /* Tell session daemon we are ready to receive the metadata. */
1406 ret
= consumer_send_status_msg(sock
, LTTCOMM_CONSUMERD_SUCCESS
);
1408 /* Somehow, the session daemon is not responding anymore. */
1412 /* Wait for more data. */
1413 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
1417 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1420 /* error receiving from sessiond */
1424 goto end_msg_sessiond
;
1427 case LTTNG_CONSUMER_SETUP_METADATA
:
1431 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1435 goto end_msg_sessiond
;
1437 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1439 if (msg
.u
.snapshot_channel
.metadata
) {
1440 ret
= snapshot_metadata(msg
.u
.snapshot_channel
.key
,
1441 msg
.u
.snapshot_channel
.pathname
,
1442 msg
.u
.snapshot_channel
.relayd_id
,
1445 ERR("Snapshot metadata failed");
1446 ret_code
= LTTNG_ERR_UST_META_FAIL
;
1449 ret
= snapshot_channel(msg
.u
.snapshot_channel
.key
,
1450 msg
.u
.snapshot_channel
.pathname
,
1451 msg
.u
.snapshot_channel
.relayd_id
,
1452 msg
.u
.snapshot_channel
.max_stream_size
,
1455 ERR("Snapshot channel failed");
1456 ret_code
= LTTNG_ERR_UST_CHAN_FAIL
;
1460 ret
= consumer_send_status_msg(sock
, ret_code
);
1462 /* Somehow, the session daemon is not responding anymore. */
1475 * Return 1 to indicate success since the 0 value can be a socket
1476 * shutdown during the recv() or send() call.
1482 * The returned value here is not useful since either way we'll return 1 to
1483 * the caller because the session daemon socket management is done
1484 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1486 ret
= consumer_send_status_msg(sock
, ret_code
);
1495 * Free channel here since no one has a reference to it. We don't
1496 * free after that because a stream can store this pointer.
1498 destroy_channel(channel
);
1500 /* We have to send a status channel message indicating an error. */
1501 ret
= consumer_send_status_channel(sock
, NULL
);
1503 /* Stop everything if session daemon can not be notified. */
1510 /* This will issue a consumer stop. */
1515 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1516 * compiled out, we isolate it in this library.
1518 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1522 assert(stream
->ustream
);
1524 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1528 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1529 * compiled out, we isolate it in this library.
1531 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1534 assert(stream
->ustream
);
1536 return ustctl_get_mmap_base(stream
->ustream
);
1540 * Take a snapshot for a specific fd
1542 * Returns 0 on success, < 0 on error
1544 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1547 assert(stream
->ustream
);
1549 return ustctl_snapshot(stream
->ustream
);
1553 * Get the produced position
1555 * Returns 0 on success, < 0 on error
1557 int lttng_ustconsumer_get_produced_snapshot(
1558 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1561 assert(stream
->ustream
);
1564 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1568 * Get the consumed position
1570 * Returns 0 on success, < 0 on error
1572 int lttng_ustconsumer_get_consumed_snapshot(
1573 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1576 assert(stream
->ustream
);
1579 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
1583 * Called when the stream signal the consumer that it has hang up.
1585 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1588 assert(stream
->ustream
);
1590 ustctl_flush_buffer(stream
->ustream
, 0);
1591 stream
->hangup_flush_done
= 1;
1594 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1597 assert(chan
->uchan
);
1599 if (chan
->switch_timer_enabled
== 1) {
1600 consumer_timer_switch_stop(chan
);
1602 consumer_metadata_cache_destroy(chan
);
1603 ustctl_destroy_channel(chan
->uchan
);
1606 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
1609 assert(stream
->ustream
);
1611 if (stream
->chan
->switch_timer_enabled
== 1) {
1612 consumer_timer_switch_stop(stream
->chan
);
1614 ustctl_destroy_stream(stream
->ustream
);
1617 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
1618 struct lttng_consumer_local_data
*ctx
)
1620 unsigned long len
, subbuf_size
, padding
;
1624 struct ustctl_consumer_stream
*ustream
;
1627 assert(stream
->ustream
);
1630 DBG("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
1633 /* Ease our life for what's next. */
1634 ustream
= stream
->ustream
;
1636 /* We can consume the 1 byte written into the wait_fd by UST */
1637 if (stream
->monitor
&& !stream
->hangup_flush_done
) {
1641 readlen
= read(stream
->wait_fd
, &dummy
, 1);
1642 } while (readlen
== -1 && errno
== EINTR
);
1643 if (readlen
== -1 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
1650 /* Get the next subbuffer */
1651 err
= ustctl_get_next_subbuf(ustream
);
1654 * Populate metadata info if the existing info has
1655 * already been read.
1657 if (stream
->metadata_flag
) {
1660 if (stream
->chan
->metadata_cache
->contiguous
1661 == stream
->ust_metadata_pushed
) {
1666 write_len
= ustctl_write_one_packet_to_channel(stream
->chan
->uchan
,
1667 &stream
->chan
->metadata_cache
->data
[stream
->ust_metadata_pushed
],
1668 stream
->chan
->metadata_cache
->contiguous
1669 - stream
->ust_metadata_pushed
);
1670 assert(write_len
!= 0);
1671 if (write_len
< 0) {
1672 ERR("Writing one metadata packet");
1676 stream
->ust_metadata_pushed
+= write_len
;
1677 ustctl_flush_buffer(stream
->ustream
, 1);
1681 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
1683 * This is a debug message even for single-threaded consumer,
1684 * because poll() have more relaxed criterions than get subbuf,
1685 * so get_subbuf may fail for short race windows where poll()
1686 * would issue wakeups.
1688 DBG("Reserving sub buffer failed (everything is normal, "
1689 "it is due to concurrency) [ret: %d]", err
);
1692 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
1693 /* Get the full padded subbuffer size */
1694 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
1697 /* Get subbuffer data size (without padding) */
1698 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
1701 /* Make sure we don't get a subbuffer size bigger than the padded */
1702 assert(len
>= subbuf_size
);
1704 padding
= len
- subbuf_size
;
1705 /* write the subbuffer to the tracefile */
1706 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
);
1708 * The mmap operation should write subbuf_size amount of data when network
1709 * streaming or the full padding (len) size when we are _not_ streaming.
1711 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
1712 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
1714 * Display the error but continue processing to try to release the
1715 * subbuffer. This is a DBG statement since any unexpected kill or
1716 * signal, the application gets unregistered, relayd gets closed or
1717 * anything that affects the buffer lifetime will trigger this error.
1718 * So, for the sake of the user, don't print this error since it can
1719 * happen and it is OK with the code flow.
1721 DBG("Error writing to tracefile "
1722 "(ret: %ld != len: %lu != subbuf_size: %lu)",
1723 ret
, len
, subbuf_size
);
1725 err
= ustctl_put_next_subbuf(ustream
);
1733 * Called when a stream is created.
1735 * Return 0 on success or else a negative value.
1737 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
1743 /* Don't create anything if this is set for streaming. */
1744 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
) {
1745 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
1746 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
1747 stream
->uid
, stream
->gid
);
1751 stream
->out_fd
= ret
;
1752 stream
->tracefile_size_current
= 0;
1761 * Check if data is still being extracted from the buffers for a specific
1762 * stream. Consumer data lock MUST be acquired before calling this function
1763 * and the stream lock.
1765 * Return 1 if the traced data are still getting read else 0 meaning that the
1766 * data is available for trace viewer reading.
1768 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
1773 assert(stream
->ustream
);
1775 DBG("UST consumer checking data pending");
1777 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
1782 if (stream
->chan
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
1783 uint64_t contiguous
, pushed
;
1785 /* Ease our life a bit. */
1786 contiguous
= stream
->chan
->metadata_cache
->contiguous
;
1787 pushed
= stream
->ust_metadata_pushed
;
1790 * We can simply check whether all contiguously available data
1791 * has been pushed to the ring buffer, since the push operation
1792 * is performed within get_next_subbuf(), and because both
1793 * get_next_subbuf() and put_next_subbuf() are issued atomically
1794 * thanks to the stream lock within
1795 * lttng_ustconsumer_read_subbuffer(). This basically means that
1796 * whetnever ust_metadata_pushed is incremented, the associated
1797 * metadata has been consumed from the metadata stream.
1799 DBG("UST consumer metadata pending check: contiguous %" PRIu64
" vs pushed %" PRIu64
,
1800 contiguous
, pushed
);
1801 assert(((int64_t) contiguous
- pushed
) >= 0);
1802 if ((contiguous
!= pushed
) ||
1803 (((int64_t) contiguous
- pushed
) > 0 || contiguous
== 0)) {
1804 ret
= 1; /* Data is pending */
1808 ret
= ustctl_get_next_subbuf(stream
->ustream
);
1811 * There is still data so let's put back this
1814 ret
= ustctl_put_subbuf(stream
->ustream
);
1816 ret
= 1; /* Data is pending */
1821 /* Data is NOT pending so ready to be read. */
1829 * Close every metadata stream wait fd of the metadata hash table. This
1830 * function MUST be used very carefully so not to run into a race between the
1831 * metadata thread handling streams and this function closing their wait fd.
1833 * For UST, this is used when the session daemon hangs up. Its the metadata
1834 * producer so calling this is safe because we are assured that no state change
1835 * can occur in the metadata thread for the streams in the hash table.
1837 void lttng_ustconsumer_close_metadata(struct lttng_ht
*metadata_ht
)
1839 struct lttng_ht_iter iter
;
1840 struct lttng_consumer_stream
*stream
;
1842 assert(metadata_ht
);
1843 assert(metadata_ht
->ht
);
1845 DBG("UST consumer closing all metadata streams");
1848 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
1850 pthread_mutex_lock(&stream
->chan
->lock
);
1852 * Whatever returned value, we must continue to try to close everything
1855 (void) _close_metadata(stream
->chan
);
1856 DBG("Metadata wait fd %d and poll pipe fd %d closed", stream
->wait_fd
,
1857 stream
->ust_metadata_poll_pipe
[1]);
1858 pthread_mutex_unlock(&stream
->chan
->lock
);
1864 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
1868 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
1870 ERR("Unable to close wakeup fd");
1875 * Please refer to consumer-timer.c before adding any lock within this
1876 * function or any of its callees. Timers have a very strict locking
1877 * semantic with respect to teardown. Failure to respect this semantic
1878 * introduces deadlocks.
1880 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
1881 struct lttng_consumer_channel
*channel
, int timer
)
1883 struct lttcomm_metadata_request_msg request
;
1884 struct lttcomm_consumer_msg msg
;
1885 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1886 uint64_t len
, key
, offset
;
1890 assert(channel
->metadata_cache
);
1892 /* send the metadata request to sessiond */
1893 switch (consumer_data
.type
) {
1894 case LTTNG_CONSUMER64_UST
:
1895 request
.bits_per_long
= 64;
1897 case LTTNG_CONSUMER32_UST
:
1898 request
.bits_per_long
= 32;
1901 request
.bits_per_long
= 0;
1905 request
.session_id
= channel
->session_id
;
1906 request
.session_id_per_pid
= channel
->session_id_per_pid
;
1908 * Request the application UID here so the metadata of that application can
1909 * be sent back. The channel UID corresponds to the user UID of the session
1910 * used for the rights on the stream file(s).
1912 request
.uid
= channel
->ust_app_uid
;
1913 request
.key
= channel
->key
;
1915 DBG("Sending metadata request to sessiond, session id %" PRIu64
1916 ", per-pid %" PRIu64
", app UID %u and channek key %" PRIu64
,
1917 request
.session_id
, request
.session_id_per_pid
, request
.uid
,
1920 pthread_mutex_lock(&ctx
->metadata_socket_lock
);
1921 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
1924 ERR("Asking metadata to sessiond");
1928 /* Receive the metadata from sessiond */
1929 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
1931 if (ret
!= sizeof(msg
)) {
1932 DBG("Consumer received unexpected message size %d (expects %zu)",
1934 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1936 * The ret value might 0 meaning an orderly shutdown but this is ok
1937 * since the caller handles this.
1942 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
1943 /* No registry found */
1944 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
1948 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
1949 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
1954 len
= msg
.u
.push_metadata
.len
;
1955 key
= msg
.u
.push_metadata
.key
;
1956 offset
= msg
.u
.push_metadata
.target_offset
;
1958 assert(key
== channel
->key
);
1960 DBG("No new metadata to receive for key %" PRIu64
, key
);
1963 /* Tell session daemon we are ready to receive the metadata. */
1964 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
1965 LTTCOMM_CONSUMERD_SUCCESS
);
1966 if (ret
< 0 || len
== 0) {
1968 * Somehow, the session daemon is not responding anymore or there is
1969 * nothing to receive.
1974 ret
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
1975 key
, offset
, len
, channel
, timer
);
1978 * Only send the status msg if the sessiond is alive meaning a positive
1981 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret
);
1986 pthread_mutex_unlock(&ctx
->metadata_socket_lock
);