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 <bin/lttng-consumerd/health-consumerd.h>
36 #include <common/common.h>
37 #include <common/sessiond-comm/sessiond-comm.h>
38 #include <common/relayd/relayd.h>
39 #include <common/compat/fcntl.h>
40 #include <common/compat/endian.h>
41 #include <common/consumer-metadata-cache.h>
42 #include <common/consumer-stream.h>
43 #include <common/consumer-timer.h>
44 #include <common/utils.h>
45 #include <common/index/index.h>
47 #include "ust-consumer.h"
49 extern struct lttng_consumer_global_data consumer_data
;
50 extern int consumer_poll_timeout
;
51 extern volatile int consumer_quit
;
54 * Free channel object and all streams associated with it. This MUST be used
55 * only and only if the channel has _NEVER_ been added to the global channel
58 static void destroy_channel(struct lttng_consumer_channel
*channel
)
60 struct lttng_consumer_stream
*stream
, *stmp
;
64 DBG("UST consumer cleaning stream list");
66 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
71 cds_list_del(&stream
->send_node
);
72 ustctl_destroy_stream(stream
->ustream
);
77 * If a channel is available meaning that was created before the streams
81 lttng_ustconsumer_del_channel(channel
);
82 lttng_ustconsumer_free_channel(channel
);
88 * Add channel to internal consumer state.
90 * Returns 0 on success or else a negative value.
92 static int add_channel(struct lttng_consumer_channel
*channel
,
93 struct lttng_consumer_local_data
*ctx
)
100 if (ctx
->on_recv_channel
!= NULL
) {
101 ret
= ctx
->on_recv_channel(channel
);
103 ret
= consumer_add_channel(channel
, ctx
);
104 } else if (ret
< 0) {
105 /* Most likely an ENOMEM. */
106 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
110 ret
= consumer_add_channel(channel
, ctx
);
113 DBG("UST consumer channel added (key: %" PRIu64
")", channel
->key
);
120 * Allocate and return a consumer channel object.
122 static struct lttng_consumer_channel
*allocate_channel(uint64_t session_id
,
123 const char *pathname
, const char *name
, uid_t uid
, gid_t gid
,
124 uint64_t relayd_id
, uint64_t key
, enum lttng_event_output output
,
125 uint64_t tracefile_size
, uint64_t tracefile_count
,
126 uint64_t session_id_per_pid
, unsigned int monitor
,
127 unsigned int live_timer_interval
)
132 return consumer_allocate_channel(key
, session_id
, pathname
, name
, uid
,
133 gid
, relayd_id
, output
, tracefile_size
,
134 tracefile_count
, session_id_per_pid
, monitor
, live_timer_interval
);
138 * Allocate and return a consumer stream object. If _alloc_ret is not NULL, the
139 * error value if applicable is set in it else it is kept untouched.
141 * Return NULL on error else the newly allocated stream object.
143 static struct lttng_consumer_stream
*allocate_stream(int cpu
, int key
,
144 struct lttng_consumer_channel
*channel
,
145 struct lttng_consumer_local_data
*ctx
, int *_alloc_ret
)
148 struct lttng_consumer_stream
*stream
= NULL
;
153 stream
= consumer_allocate_stream(channel
->key
,
155 LTTNG_CONSUMER_ACTIVE_STREAM
,
165 if (stream
== NULL
) {
169 * We could not find the channel. Can happen if cpu hotplug
170 * happens while tearing down.
172 DBG3("Could not find channel");
177 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
183 stream
->chan
= channel
;
187 *_alloc_ret
= alloc_ret
;
193 * Send the given stream pointer to the corresponding thread.
195 * Returns 0 on success else a negative value.
197 static int send_stream_to_thread(struct lttng_consumer_stream
*stream
,
198 struct lttng_consumer_local_data
*ctx
)
201 struct lttng_pipe
*stream_pipe
;
203 /* Get the right pipe where the stream will be sent. */
204 if (stream
->metadata_flag
) {
205 ret
= consumer_add_metadata_stream(stream
);
207 ERR("Consumer add metadata stream %" PRIu64
" failed.",
211 stream_pipe
= ctx
->consumer_metadata_pipe
;
213 ret
= consumer_add_data_stream(stream
);
215 ERR("Consumer add stream %" PRIu64
" failed.",
219 stream_pipe
= ctx
->consumer_data_pipe
;
223 * From this point on, the stream's ownership has been moved away from
224 * the channel and becomes globally visible.
226 stream
->globally_visible
= 1;
228 ret
= lttng_pipe_write(stream_pipe
, &stream
, sizeof(stream
));
230 ERR("Consumer write %s stream to pipe %d",
231 stream
->metadata_flag
? "metadata" : "data",
232 lttng_pipe_get_writefd(stream_pipe
));
233 if (stream
->metadata_flag
) {
234 consumer_del_stream_for_metadata(stream
);
236 consumer_del_stream_for_data(stream
);
244 * Create streams for the given channel using liblttng-ust-ctl.
246 * Return 0 on success else a negative value.
248 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
249 struct lttng_consumer_local_data
*ctx
)
252 struct ustctl_consumer_stream
*ustream
;
253 struct lttng_consumer_stream
*stream
;
259 * While a stream is available from ustctl. When NULL is returned, we've
260 * reached the end of the possible stream for the channel.
262 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
264 int ust_metadata_pipe
[2];
266 health_code_update();
268 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& channel
->monitor
) {
269 ret
= utils_create_pipe_cloexec_nonblock(ust_metadata_pipe
);
271 ERR("Create ust metadata poll pipe");
274 wait_fd
= ust_metadata_pipe
[0];
276 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
279 /* Allocate consumer stream object. */
280 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
284 stream
->ustream
= ustream
;
286 * Store it so we can save multiple function calls afterwards since
287 * this value is used heavily in the stream threads. This is UST
288 * specific so this is why it's done after allocation.
290 stream
->wait_fd
= wait_fd
;
293 * Increment channel refcount since the channel reference has now been
294 * assigned in the allocation process above.
296 if (stream
->chan
->monitor
) {
297 uatomic_inc(&stream
->chan
->refcount
);
301 * Order is important this is why a list is used. On error, the caller
302 * should clean this list.
304 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
306 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
307 &stream
->max_sb_size
);
309 ERR("ustctl_get_max_subbuf_size failed for stream %s",
314 /* Do actions once stream has been received. */
315 if (ctx
->on_recv_stream
) {
316 ret
= ctx
->on_recv_stream(stream
);
322 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
323 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
325 /* Set next CPU stream. */
326 channel
->streams
.count
= ++cpu
;
328 /* Keep stream reference when creating metadata. */
329 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
330 channel
->metadata_stream
= stream
;
331 if (channel
->monitor
) {
332 /* Set metadata poll pipe if we created one */
333 memcpy(stream
->ust_metadata_poll_pipe
,
335 sizeof(ust_metadata_pipe
));
348 * Create an UST channel with the given attributes and send it to the session
349 * daemon using the ust ctl API.
351 * Return 0 on success or else a negative value.
353 static int create_ust_channel(struct ustctl_consumer_channel_attr
*attr
,
354 struct ustctl_consumer_channel
**chanp
)
357 struct ustctl_consumer_channel
*channel
;
362 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
363 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
364 "switch_timer_interval: %u, read_timer_interval: %u, "
365 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
366 attr
->num_subbuf
, attr
->switch_timer_interval
,
367 attr
->read_timer_interval
, attr
->output
, attr
->type
);
369 channel
= ustctl_create_channel(attr
);
384 * Send a single given stream to the session daemon using the sock.
386 * Return 0 on success else a negative value.
388 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
395 DBG("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
397 /* Send stream to session daemon. */
398 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
408 * Send channel to sessiond.
410 * Return 0 on success or else a negative value.
412 static int send_sessiond_channel(int sock
,
413 struct lttng_consumer_channel
*channel
,
414 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
416 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
417 struct lttng_consumer_stream
*stream
;
418 uint64_t net_seq_idx
= -1ULL;
424 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
426 if (channel
->relayd_id
!= (uint64_t) -1ULL) {
427 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
429 health_code_update();
431 /* Try to send the stream to the relayd if one is available. */
432 ret
= consumer_send_relayd_stream(stream
, stream
->chan
->pathname
);
435 * Flag that the relayd was the problem here probably due to a
436 * communicaton error on the socket.
441 ret_code
= LTTNG_ERR_RELAYD_CONNECT_FAIL
;
443 if (net_seq_idx
== -1ULL) {
444 net_seq_idx
= stream
->net_seq_idx
;
449 /* Inform sessiond that we are about to send channel and streams. */
450 ret
= consumer_send_status_msg(sock
, ret_code
);
451 if (ret
< 0 || ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
453 * Either the session daemon is not responding or the relayd died so we
459 /* Send channel to sessiond. */
460 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
465 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
470 /* The channel was sent successfully to the sessiond at this point. */
471 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
473 health_code_update();
475 /* Send stream to session daemon. */
476 ret
= send_sessiond_stream(sock
, stream
);
482 /* Tell sessiond there is no more stream. */
483 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
488 DBG("UST consumer NULL stream sent to sessiond");
493 if (ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
500 * Creates a channel and streams and add the channel it to the channel internal
501 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
504 * Return 0 on success or else, a negative value is returned and the channel
505 * MUST be destroyed by consumer_del_channel().
507 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
508 struct lttng_consumer_channel
*channel
,
509 struct ustctl_consumer_channel_attr
*attr
)
518 * This value is still used by the kernel consumer since for the kernel,
519 * the stream ownership is not IN the consumer so we need to have the
520 * number of left stream that needs to be initialized so we can know when
521 * to delete the channel (see consumer.c).
523 * As for the user space tracer now, the consumer creates and sends the
524 * stream to the session daemon which only sends them to the application
525 * once every stream of a channel is received making this value useless
526 * because we they will be added to the poll thread before the application
527 * receives them. This ensures that a stream can not hang up during
528 * initilization of a channel.
530 channel
->nb_init_stream_left
= 0;
532 /* The reply msg status is handled in the following call. */
533 ret
= create_ust_channel(attr
, &channel
->uchan
);
538 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
541 * For the snapshots (no monitor), we create the metadata streams
542 * on demand, not during the channel creation.
544 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& !channel
->monitor
) {
549 /* Open all streams for this channel. */
550 ret
= create_ust_streams(channel
, ctx
);
560 * Send all stream of a channel to the right thread handling it.
562 * On error, return a negative value else 0 on success.
564 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
565 struct lttng_consumer_local_data
*ctx
)
568 struct lttng_consumer_stream
*stream
, *stmp
;
573 /* Send streams to the corresponding thread. */
574 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
577 health_code_update();
579 /* Sending the stream to the thread. */
580 ret
= send_stream_to_thread(stream
, ctx
);
583 * If we are unable to send the stream to the thread, there is
584 * a big problem so just stop everything.
586 /* Remove node from the channel stream list. */
587 cds_list_del(&stream
->send_node
);
591 /* Remove node from the channel stream list. */
592 cds_list_del(&stream
->send_node
);
601 * Flush channel's streams using the given key to retrieve the channel.
603 * Return 0 on success else an LTTng error code.
605 static int flush_channel(uint64_t chan_key
)
608 struct lttng_consumer_channel
*channel
;
609 struct lttng_consumer_stream
*stream
;
611 struct lttng_ht_iter iter
;
613 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
616 channel
= consumer_find_channel(chan_key
);
618 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
619 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
623 ht
= consumer_data
.stream_per_chan_id_ht
;
625 /* For each stream of the channel id, flush it. */
626 cds_lfht_for_each_entry_duplicate(ht
->ht
,
627 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
628 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
630 health_code_update();
632 pthread_mutex_lock(&stream
->lock
);
633 if (!stream
->quiescent
) {
634 ustctl_flush_buffer(stream
->ustream
, 0);
635 stream
->quiescent
= true;
637 pthread_mutex_unlock(&stream
->lock
);
645 * Clear quiescent state from channel's streams using the given key to
646 * retrieve the channel.
648 * Return 0 on success else an LTTng error code.
650 static int clear_quiescent_channel(uint64_t chan_key
)
653 struct lttng_consumer_channel
*channel
;
654 struct lttng_consumer_stream
*stream
;
656 struct lttng_ht_iter iter
;
658 DBG("UST consumer clear quiescent channel key %" PRIu64
, chan_key
);
661 channel
= consumer_find_channel(chan_key
);
663 ERR("UST consumer clear quiescent channel %" PRIu64
" not found", chan_key
);
664 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
668 ht
= consumer_data
.stream_per_chan_id_ht
;
670 /* For each stream of the channel id, clear quiescent state. */
671 cds_lfht_for_each_entry_duplicate(ht
->ht
,
672 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
673 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
675 health_code_update();
677 pthread_mutex_lock(&stream
->lock
);
678 stream
->quiescent
= false;
679 pthread_mutex_unlock(&stream
->lock
);
687 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
688 * RCU read side lock MUST be acquired before calling this function.
690 * Return 0 on success else an LTTng error code.
692 static int close_metadata(uint64_t chan_key
)
695 struct lttng_consumer_channel
*channel
;
697 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
699 channel
= consumer_find_channel(chan_key
);
702 * This is possible if the metadata thread has issue a delete because
703 * the endpoint point of the stream hung up. There is no way the
704 * session daemon can know about it thus use a DBG instead of an actual
707 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
708 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
712 pthread_mutex_lock(&consumer_data
.lock
);
713 pthread_mutex_lock(&channel
->lock
);
715 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
719 lttng_ustconsumer_close_metadata(channel
);
722 pthread_mutex_unlock(&channel
->lock
);
723 pthread_mutex_unlock(&consumer_data
.lock
);
729 * RCU read side lock MUST be acquired before calling this function.
731 * Return 0 on success else an LTTng error code.
733 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
736 struct lttng_consumer_channel
*metadata
;
738 DBG("UST consumer setup metadata key %" PRIu64
, key
);
740 metadata
= consumer_find_channel(key
);
742 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
743 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
748 * In no monitor mode, the metadata channel has no stream(s) so skip the
749 * ownership transfer to the metadata thread.
751 if (!metadata
->monitor
) {
752 DBG("Metadata channel in no monitor");
758 * Send metadata stream to relayd if one available. Availability is
759 * known if the stream is still in the list of the channel.
761 if (cds_list_empty(&metadata
->streams
.head
)) {
762 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
763 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
764 goto error_no_stream
;
767 /* Send metadata stream to relayd if needed. */
768 if (metadata
->metadata_stream
->net_seq_idx
!= (uint64_t) -1ULL) {
769 ret
= consumer_send_relayd_stream(metadata
->metadata_stream
,
772 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
775 ret
= consumer_send_relayd_streams_sent(
776 metadata
->metadata_stream
->net_seq_idx
);
778 ret
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
783 ret
= send_streams_to_thread(metadata
, ctx
);
786 * If we are unable to send the stream to the thread, there is
787 * a big problem so just stop everything.
789 ret
= LTTCOMM_CONSUMERD_FATAL
;
792 /* List MUST be empty after or else it could be reused. */
793 assert(cds_list_empty(&metadata
->streams
.head
));
800 * Delete metadata channel on error. At this point, the metadata stream can
801 * NOT be monitored by the metadata thread thus having the guarantee that
802 * the stream is still in the local stream list of the channel. This call
803 * will make sure to clean that list.
805 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
806 cds_list_del(&metadata
->metadata_stream
->send_node
);
807 metadata
->metadata_stream
= NULL
;
814 * Snapshot the whole metadata.
816 * Returns 0 on success, < 0 on error
818 static int snapshot_metadata(uint64_t key
, char *path
, uint64_t relayd_id
,
819 struct lttng_consumer_local_data
*ctx
)
822 struct lttng_consumer_channel
*metadata_channel
;
823 struct lttng_consumer_stream
*metadata_stream
;
828 DBG("UST consumer snapshot metadata with key %" PRIu64
" at path %s",
833 metadata_channel
= consumer_find_channel(key
);
834 if (!metadata_channel
) {
835 ERR("UST snapshot metadata channel not found for key %" PRIu64
,
840 assert(!metadata_channel
->monitor
);
842 health_code_update();
845 * Ask the sessiond if we have new metadata waiting and update the
846 * consumer metadata cache.
848 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
, 0, 1);
853 health_code_update();
856 * The metadata stream is NOT created in no monitor mode when the channel
857 * is created on a sessiond ask channel command.
859 ret
= create_ust_streams(metadata_channel
, ctx
);
864 metadata_stream
= metadata_channel
->metadata_stream
;
865 assert(metadata_stream
);
867 if (relayd_id
!= (uint64_t) -1ULL) {
868 metadata_stream
->net_seq_idx
= relayd_id
;
869 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
874 ret
= utils_create_stream_file(path
, metadata_stream
->name
,
875 metadata_stream
->chan
->tracefile_size
,
876 metadata_stream
->tracefile_count_current
,
877 metadata_stream
->uid
, metadata_stream
->gid
, NULL
);
881 metadata_stream
->out_fd
= ret
;
882 metadata_stream
->tracefile_size_current
= 0;
886 health_code_update();
888 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
);
896 * Clean up the stream completly because the next snapshot will use a new
899 consumer_stream_destroy(metadata_stream
, NULL
);
900 cds_list_del(&metadata_stream
->send_node
);
901 metadata_channel
->metadata_stream
= NULL
;
909 * Take a snapshot of all the stream of a channel.
911 * Returns 0 on success, < 0 on error
913 static int snapshot_channel(uint64_t key
, char *path
, uint64_t relayd_id
,
914 uint64_t nb_packets_per_stream
, struct lttng_consumer_local_data
*ctx
)
917 unsigned use_relayd
= 0;
918 unsigned long consumed_pos
, produced_pos
;
919 struct lttng_consumer_channel
*channel
;
920 struct lttng_consumer_stream
*stream
;
927 if (relayd_id
!= (uint64_t) -1ULL) {
931 channel
= consumer_find_channel(key
);
933 ERR("UST snapshot channel not found for key %" PRIu64
, key
);
937 assert(!channel
->monitor
);
938 DBG("UST consumer snapshot channel %" PRIu64
, key
);
940 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
942 health_code_update();
944 /* Lock stream because we are about to change its state. */
945 pthread_mutex_lock(&stream
->lock
);
946 stream
->net_seq_idx
= relayd_id
;
949 ret
= consumer_send_relayd_stream(stream
, path
);
954 ret
= utils_create_stream_file(path
, stream
->name
,
955 stream
->chan
->tracefile_size
,
956 stream
->tracefile_count_current
,
957 stream
->uid
, stream
->gid
, NULL
);
961 stream
->out_fd
= ret
;
962 stream
->tracefile_size_current
= 0;
964 DBG("UST consumer snapshot stream %s/%s (%" PRIu64
")", path
,
965 stream
->name
, stream
->key
);
967 if (relayd_id
!= -1ULL) {
968 ret
= consumer_send_relayd_streams_sent(relayd_id
);
974 ustctl_flush_buffer(stream
->ustream
, 1);
976 ret
= lttng_ustconsumer_take_snapshot(stream
);
978 ERR("Taking UST snapshot");
982 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
984 ERR("Produced UST snapshot position");
988 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
990 ERR("Consumerd UST snapshot position");
995 * The original value is sent back if max stream size is larger than
996 * the possible size of the snapshot. Also, we assume that the session
997 * daemon should never send a maximum stream size that is lower than
1000 consumed_pos
= consumer_get_consume_start_pos(consumed_pos
,
1001 produced_pos
, nb_packets_per_stream
,
1002 stream
->max_sb_size
);
1004 while (consumed_pos
< produced_pos
) {
1006 unsigned long len
, padded_len
;
1008 health_code_update();
1010 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
1012 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
1014 if (ret
!= -EAGAIN
) {
1015 PERROR("ustctl_get_subbuf snapshot");
1016 goto error_close_stream
;
1018 DBG("UST consumer get subbuf failed. Skipping it.");
1019 consumed_pos
+= stream
->max_sb_size
;
1023 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
1025 ERR("Snapshot ustctl_get_subbuf_size");
1026 goto error_put_subbuf
;
1029 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
1031 ERR("Snapshot ustctl_get_padded_subbuf_size");
1032 goto error_put_subbuf
;
1035 read_len
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, len
,
1036 padded_len
- len
, NULL
);
1038 if (read_len
!= len
) {
1040 goto error_put_subbuf
;
1043 if (read_len
!= padded_len
) {
1045 goto error_put_subbuf
;
1049 ret
= ustctl_put_subbuf(stream
->ustream
);
1051 ERR("Snapshot ustctl_put_subbuf");
1052 goto error_close_stream
;
1054 consumed_pos
+= stream
->max_sb_size
;
1057 /* Simply close the stream so we can use it on the next snapshot. */
1058 consumer_stream_close(stream
);
1059 pthread_mutex_unlock(&stream
->lock
);
1066 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
1067 ERR("Snapshot ustctl_put_subbuf");
1070 consumer_stream_close(stream
);
1072 pthread_mutex_unlock(&stream
->lock
);
1079 * Receive the metadata updates from the sessiond. Supports receiving
1080 * overlapping metadata, but is needs to always belong to a contiguous
1081 * range starting from 0.
1082 * Be careful about the locks held when calling this function: it needs
1083 * the metadata cache flush to concurrently progress in order to
1086 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
1087 uint64_t len
, struct lttng_consumer_channel
*channel
,
1088 int timer
, int wait
)
1090 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1093 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
1095 metadata_str
= zmalloc(len
* sizeof(char));
1096 if (!metadata_str
) {
1097 PERROR("zmalloc metadata string");
1098 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
1102 health_code_update();
1104 /* Receive metadata string. */
1105 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1107 /* Session daemon is dead so return gracefully. */
1112 health_code_update();
1114 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1115 ret
= consumer_metadata_cache_write(channel
, offset
, len
, metadata_str
);
1117 /* Unable to handle metadata. Notify session daemon. */
1118 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1120 * Skip metadata flush on write error since the offset and len might
1121 * not have been updated which could create an infinite loop below when
1122 * waiting for the metadata cache to be flushed.
1124 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1127 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1132 while (consumer_metadata_cache_flushed(channel
, offset
+ len
, timer
)) {
1133 DBG("Waiting for metadata to be flushed");
1135 health_code_update();
1137 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1147 * Receive command from session daemon and process it.
1149 * Return 1 on success else a negative value or 0.
1151 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1152 int sock
, struct pollfd
*consumer_sockpoll
)
1155 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1156 struct lttcomm_consumer_msg msg
;
1157 struct lttng_consumer_channel
*channel
= NULL
;
1159 health_code_update();
1161 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1162 if (ret
!= sizeof(msg
)) {
1163 DBG("Consumer received unexpected message size %zd (expects %zu)",
1166 * The ret value might 0 meaning an orderly shutdown but this is ok
1167 * since the caller handles this.
1170 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1176 health_code_update();
1179 assert(msg
.cmd_type
!= LTTNG_CONSUMER_STOP
);
1181 health_code_update();
1183 /* relayd needs RCU read-side lock */
1186 switch (msg
.cmd_type
) {
1187 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1189 /* Session daemon status message are handled in the following call. */
1190 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1191 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1192 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
,
1193 msg
.u
.relayd_sock
.relayd_session_id
);
1196 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1198 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1199 struct consumer_relayd_sock_pair
*relayd
;
1201 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1203 /* Get relayd reference if exists. */
1204 relayd
= consumer_find_relayd(index
);
1205 if (relayd
== NULL
) {
1206 DBG("Unable to find relayd %" PRIu64
, index
);
1207 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
1211 * Each relayd socket pair has a refcount of stream attached to it
1212 * which tells if the relayd is still active or not depending on the
1215 * This will set the destroy flag of the relayd object and destroy it
1216 * if the refcount reaches zero when called.
1218 * The destroy can happen either here or when a stream fd hangs up.
1221 consumer_flag_relayd_for_destroy(relayd
);
1224 goto end_msg_sessiond
;
1226 case LTTNG_CONSUMER_UPDATE_STREAM
:
1231 case LTTNG_CONSUMER_DATA_PENDING
:
1233 int ret
, is_data_pending
;
1234 uint64_t id
= msg
.u
.data_pending
.session_id
;
1236 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1238 is_data_pending
= consumer_data_pending(id
);
1240 /* Send back returned value to session daemon */
1241 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1242 sizeof(is_data_pending
));
1244 DBG("Error when sending the data pending ret code: %d", ret
);
1249 * No need to send back a status message since the data pending
1250 * returned value is the response.
1254 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1257 struct ustctl_consumer_channel_attr attr
;
1259 /* Create a plain object and reserve a channel key. */
1260 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
1261 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
1262 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
1263 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
1264 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1265 msg
.u
.ask_channel
.tracefile_size
,
1266 msg
.u
.ask_channel
.tracefile_count
,
1267 msg
.u
.ask_channel
.session_id_per_pid
,
1268 msg
.u
.ask_channel
.monitor
,
1269 msg
.u
.ask_channel
.live_timer_interval
);
1271 goto end_channel_error
;
1275 * Assign UST application UID to the channel. This value is ignored for
1276 * per PID buffers. This is specific to UST thus setting this after the
1279 channel
->ust_app_uid
= msg
.u
.ask_channel
.ust_app_uid
;
1281 /* Build channel attributes from received message. */
1282 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1283 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1284 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1285 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1286 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1287 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1288 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1290 /* Match channel buffer type to the UST abi. */
1291 switch (msg
.u
.ask_channel
.output
) {
1292 case LTTNG_EVENT_MMAP
:
1294 attr
.output
= LTTNG_UST_MMAP
;
1298 /* Translate and save channel type. */
1299 switch (msg
.u
.ask_channel
.type
) {
1300 case LTTNG_UST_CHAN_PER_CPU
:
1301 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1302 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1304 * Set refcount to 1 for owner. Below, we will
1305 * pass ownership to the
1306 * consumer_thread_channel_poll() thread.
1308 channel
->refcount
= 1;
1310 case LTTNG_UST_CHAN_METADATA
:
1311 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1312 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1319 health_code_update();
1321 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
1323 goto end_channel_error
;
1326 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1327 ret
= consumer_metadata_cache_allocate(channel
);
1329 ERR("Allocating metadata cache");
1330 goto end_channel_error
;
1332 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1333 attr
.switch_timer_interval
= 0;
1335 consumer_timer_live_start(channel
,
1336 msg
.u
.ask_channel
.live_timer_interval
);
1339 health_code_update();
1342 * Add the channel to the internal state AFTER all streams were created
1343 * and successfully sent to session daemon. This way, all streams must
1344 * be ready before this channel is visible to the threads.
1345 * If add_channel succeeds, ownership of the channel is
1346 * passed to consumer_thread_channel_poll().
1348 ret
= add_channel(channel
, ctx
);
1350 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1351 if (channel
->switch_timer_enabled
== 1) {
1352 consumer_timer_switch_stop(channel
);
1354 consumer_metadata_cache_destroy(channel
);
1356 if (channel
->live_timer_enabled
== 1) {
1357 consumer_timer_live_stop(channel
);
1359 goto end_channel_error
;
1362 health_code_update();
1365 * Channel and streams are now created. Inform the session daemon that
1366 * everything went well and should wait to receive the channel and
1367 * streams with ustctl API.
1369 ret
= consumer_send_status_channel(sock
, channel
);
1372 * There is probably a problem on the socket.
1379 case LTTNG_CONSUMER_GET_CHANNEL
:
1381 int ret
, relayd_err
= 0;
1382 uint64_t key
= msg
.u
.get_channel
.key
;
1383 struct lttng_consumer_channel
*channel
;
1385 channel
= consumer_find_channel(key
);
1387 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1388 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1389 goto end_msg_sessiond
;
1392 health_code_update();
1394 /* Send everything to sessiond. */
1395 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1399 * We were unable to send to the relayd the stream so avoid
1400 * sending back a fatal error to the thread since this is OK
1401 * and the consumer can continue its work. The above call
1402 * has sent the error status message to the sessiond.
1407 * The communicaton was broken hence there is a bad state between
1408 * the consumer and sessiond so stop everything.
1413 health_code_update();
1416 * In no monitor mode, the streams ownership is kept inside the channel
1417 * so don't send them to the data thread.
1419 if (!channel
->monitor
) {
1420 goto end_msg_sessiond
;
1423 ret
= send_streams_to_thread(channel
, ctx
);
1426 * If we are unable to send the stream to the thread, there is
1427 * a big problem so just stop everything.
1431 /* List MUST be empty after or else it could be reused. */
1432 assert(cds_list_empty(&channel
->streams
.head
));
1433 goto end_msg_sessiond
;
1435 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1437 uint64_t key
= msg
.u
.destroy_channel
.key
;
1440 * Only called if streams have not been sent to stream
1441 * manager thread. However, channel has been sent to
1442 * channel manager thread.
1444 notify_thread_del_channel(ctx
, key
);
1445 goto end_msg_sessiond
;
1447 case LTTNG_CONSUMER_CLOSE_METADATA
:
1451 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1456 goto end_msg_sessiond
;
1458 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1462 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1467 goto end_msg_sessiond
;
1469 case LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL
:
1473 ret
= clear_quiescent_channel(
1474 msg
.u
.clear_quiescent_channel
.key
);
1479 goto end_msg_sessiond
;
1481 case LTTNG_CONSUMER_PUSH_METADATA
:
1484 uint64_t len
= msg
.u
.push_metadata
.len
;
1485 uint64_t key
= msg
.u
.push_metadata
.key
;
1486 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1487 struct lttng_consumer_channel
*channel
;
1489 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1492 channel
= consumer_find_channel(key
);
1495 * This is possible if the metadata creation on the consumer side
1496 * is in flight vis-a-vis a concurrent push metadata from the
1497 * session daemon. Simply return that the channel failed and the
1498 * session daemon will handle that message correctly considering
1499 * that this race is acceptable thus the DBG() statement here.
1501 DBG("UST consumer push metadata %" PRIu64
" not found", key
);
1502 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1503 goto end_msg_sessiond
;
1506 health_code_update();
1510 * There is nothing to receive. We have simply
1511 * checked whether the channel can be found.
1513 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1514 goto end_msg_sessiond
;
1517 /* Tell session daemon we are ready to receive the metadata. */
1518 ret
= consumer_send_status_msg(sock
, LTTCOMM_CONSUMERD_SUCCESS
);
1520 /* Somehow, the session daemon is not responding anymore. */
1524 health_code_update();
1526 /* Wait for more data. */
1527 health_poll_entry();
1528 ret
= lttng_consumer_poll_socket(consumer_sockpoll
);
1534 health_code_update();
1536 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1537 len
, channel
, 0, 1);
1539 /* error receiving from sessiond */
1543 goto end_msg_sessiond
;
1546 case LTTNG_CONSUMER_SETUP_METADATA
:
1550 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1554 goto end_msg_sessiond
;
1556 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1558 if (msg
.u
.snapshot_channel
.metadata
) {
1559 ret
= snapshot_metadata(msg
.u
.snapshot_channel
.key
,
1560 msg
.u
.snapshot_channel
.pathname
,
1561 msg
.u
.snapshot_channel
.relayd_id
,
1564 ERR("Snapshot metadata failed");
1565 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1568 ret
= snapshot_channel(msg
.u
.snapshot_channel
.key
,
1569 msg
.u
.snapshot_channel
.pathname
,
1570 msg
.u
.snapshot_channel
.relayd_id
,
1571 msg
.u
.snapshot_channel
.nb_packets_per_stream
,
1574 ERR("Snapshot channel failed");
1575 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1579 health_code_update();
1580 ret
= consumer_send_status_msg(sock
, ret_code
);
1582 /* Somehow, the session daemon is not responding anymore. */
1585 health_code_update();
1595 health_code_update();
1598 * Return 1 to indicate success since the 0 value can be a socket
1599 * shutdown during the recv() or send() call.
1605 * The returned value here is not useful since either way we'll return 1 to
1606 * the caller because the session daemon socket management is done
1607 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1609 ret
= consumer_send_status_msg(sock
, ret_code
);
1615 health_code_update();
1621 * Free channel here since no one has a reference to it. We don't
1622 * free after that because a stream can store this pointer.
1624 destroy_channel(channel
);
1626 /* We have to send a status channel message indicating an error. */
1627 ret
= consumer_send_status_channel(sock
, NULL
);
1629 /* Stop everything if session daemon can not be notified. */
1634 health_code_update();
1639 /* This will issue a consumer stop. */
1644 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1645 * compiled out, we isolate it in this library.
1647 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1651 assert(stream
->ustream
);
1653 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1657 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1658 * compiled out, we isolate it in this library.
1660 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1663 assert(stream
->ustream
);
1665 return ustctl_get_mmap_base(stream
->ustream
);
1669 * Take a snapshot for a specific fd
1671 * Returns 0 on success, < 0 on error
1673 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1676 assert(stream
->ustream
);
1678 return ustctl_snapshot(stream
->ustream
);
1682 * Get the produced position
1684 * Returns 0 on success, < 0 on error
1686 int lttng_ustconsumer_get_produced_snapshot(
1687 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1690 assert(stream
->ustream
);
1693 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1697 * Get the consumed position
1699 * Returns 0 on success, < 0 on error
1701 int lttng_ustconsumer_get_consumed_snapshot(
1702 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1705 assert(stream
->ustream
);
1708 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
1711 void lttng_ustconsumer_flush_buffer(struct lttng_consumer_stream
*stream
,
1715 assert(stream
->ustream
);
1717 ustctl_flush_buffer(stream
->ustream
, producer
);
1720 int lttng_ustconsumer_get_current_timestamp(
1721 struct lttng_consumer_stream
*stream
, uint64_t *ts
)
1724 assert(stream
->ustream
);
1727 return ustctl_get_current_timestamp(stream
->ustream
, ts
);
1731 * Called when the stream signals the consumer that it has hung up.
1733 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1736 assert(stream
->ustream
);
1738 pthread_mutex_lock(&stream
->lock
);
1739 if (!stream
->quiescent
) {
1740 ustctl_flush_buffer(stream
->ustream
, 0);
1741 stream
->quiescent
= true;
1743 pthread_mutex_unlock(&stream
->lock
);
1744 stream
->hangup_flush_done
= 1;
1747 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1750 assert(chan
->uchan
);
1752 if (chan
->switch_timer_enabled
== 1) {
1753 consumer_timer_switch_stop(chan
);
1757 void lttng_ustconsumer_free_channel(struct lttng_consumer_channel
*chan
)
1760 assert(chan
->uchan
);
1762 consumer_metadata_cache_destroy(chan
);
1763 ustctl_destroy_channel(chan
->uchan
);
1766 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
1769 assert(stream
->ustream
);
1771 if (stream
->chan
->switch_timer_enabled
== 1) {
1772 consumer_timer_switch_stop(stream
->chan
);
1774 ustctl_destroy_stream(stream
->ustream
);
1777 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream
*stream
)
1780 assert(stream
->ustream
);
1782 return ustctl_stream_get_wakeup_fd(stream
->ustream
);
1785 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream
*stream
)
1788 assert(stream
->ustream
);
1790 return ustctl_stream_close_wakeup_fd(stream
->ustream
);
1794 * Populate index values of a UST stream. Values are set in big endian order.
1796 * Return 0 on success or else a negative value.
1798 static int get_index_values(struct ctf_packet_index
*index
,
1799 struct ustctl_consumer_stream
*ustream
)
1803 ret
= ustctl_get_timestamp_begin(ustream
, &index
->timestamp_begin
);
1805 PERROR("ustctl_get_timestamp_begin");
1808 index
->timestamp_begin
= htobe64(index
->timestamp_begin
);
1810 ret
= ustctl_get_timestamp_end(ustream
, &index
->timestamp_end
);
1812 PERROR("ustctl_get_timestamp_end");
1815 index
->timestamp_end
= htobe64(index
->timestamp_end
);
1817 ret
= ustctl_get_events_discarded(ustream
, &index
->events_discarded
);
1819 PERROR("ustctl_get_events_discarded");
1822 index
->events_discarded
= htobe64(index
->events_discarded
);
1824 ret
= ustctl_get_content_size(ustream
, &index
->content_size
);
1826 PERROR("ustctl_get_content_size");
1829 index
->content_size
= htobe64(index
->content_size
);
1831 ret
= ustctl_get_packet_size(ustream
, &index
->packet_size
);
1833 PERROR("ustctl_get_packet_size");
1836 index
->packet_size
= htobe64(index
->packet_size
);
1838 ret
= ustctl_get_stream_id(ustream
, &index
->stream_id
);
1840 PERROR("ustctl_get_stream_id");
1843 index
->stream_id
= htobe64(index
->stream_id
);
1850 * Write up to one packet from the metadata cache to the channel.
1852 * Returns the number of bytes pushed in the cache, or a negative value
1856 int commit_one_metadata_packet(struct lttng_consumer_stream
*stream
)
1861 pthread_mutex_lock(&stream
->chan
->metadata_cache
->lock
);
1862 if (stream
->chan
->metadata_cache
->max_offset
1863 == stream
->ust_metadata_pushed
) {
1868 write_len
= ustctl_write_one_packet_to_channel(stream
->chan
->uchan
,
1869 &stream
->chan
->metadata_cache
->data
[stream
->ust_metadata_pushed
],
1870 stream
->chan
->metadata_cache
->max_offset
1871 - stream
->ust_metadata_pushed
);
1872 assert(write_len
!= 0);
1873 if (write_len
< 0) {
1874 ERR("Writing one metadata packet");
1878 stream
->ust_metadata_pushed
+= write_len
;
1880 assert(stream
->chan
->metadata_cache
->max_offset
>=
1881 stream
->ust_metadata_pushed
);
1885 pthread_mutex_unlock(&stream
->chan
->metadata_cache
->lock
);
1891 * Sync metadata meaning request them to the session daemon and snapshot to the
1892 * metadata thread can consumer them.
1894 * Metadata stream lock is held here, but we need to release it when
1895 * interacting with sessiond, else we cause a deadlock with live
1896 * awaiting on metadata to be pushed out.
1898 * Return 0 if new metadatda is available, EAGAIN if the metadata stream
1899 * is empty or a negative value on error.
1901 int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data
*ctx
,
1902 struct lttng_consumer_stream
*metadata
)
1910 pthread_mutex_unlock(&metadata
->lock
);
1912 * Request metadata from the sessiond, but don't wait for the flush
1913 * because we locked the metadata thread.
1915 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata
->chan
, 0, 0);
1919 pthread_mutex_lock(&metadata
->lock
);
1921 ret
= commit_one_metadata_packet(metadata
);
1924 } else if (ret
> 0) {
1928 ustctl_flush_buffer(metadata
->ustream
, 1);
1929 ret
= ustctl_snapshot(metadata
->ustream
);
1931 if (errno
!= EAGAIN
) {
1932 ERR("Sync metadata, taking UST snapshot");
1935 DBG("No new metadata when syncing them.");
1936 /* No new metadata, exit. */
1942 * After this flush, we still need to extract metadata.
1953 * Return 0 on success else a negative value.
1955 static int notify_if_more_data(struct lttng_consumer_stream
*stream
,
1956 struct lttng_consumer_local_data
*ctx
)
1959 struct ustctl_consumer_stream
*ustream
;
1964 ustream
= stream
->ustream
;
1967 * First, we are going to check if there is a new subbuffer available
1968 * before reading the stream wait_fd.
1970 /* Get the next subbuffer */
1971 ret
= ustctl_get_next_subbuf(ustream
);
1973 /* No more data found, flag the stream. */
1974 stream
->has_data
= 0;
1979 ret
= ustctl_put_subbuf(ustream
);
1982 /* This stream still has data. Flag it and wake up the data thread. */
1983 stream
->has_data
= 1;
1985 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !ctx
->has_wakeup
) {
1988 writelen
= lttng_pipe_write(ctx
->consumer_wakeup_pipe
, "!", 1);
1989 if (writelen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
1994 /* The wake up pipe has been notified. */
1995 ctx
->has_wakeup
= 1;
2004 * Read subbuffer from the given stream.
2006 * Stream lock MUST be acquired.
2008 * Return 0 on success else a negative value.
2010 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
2011 struct lttng_consumer_local_data
*ctx
)
2013 unsigned long len
, subbuf_size
, padding
;
2014 int err
, write_index
= 1;
2016 struct ustctl_consumer_stream
*ustream
;
2017 struct ctf_packet_index index
;
2020 assert(stream
->ustream
);
2023 DBG("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
2026 /* Ease our life for what's next. */
2027 ustream
= stream
->ustream
;
2030 * We can consume the 1 byte written into the wait_fd by UST. Don't trigger
2031 * error if we cannot read this one byte (read returns 0), or if the error
2032 * is EAGAIN or EWOULDBLOCK.
2034 * This is only done when the stream is monitored by a thread, before the
2035 * flush is done after a hangup and if the stream is not flagged with data
2036 * since there might be nothing to consume in the wait fd but still have
2037 * data available flagged by the consumer wake up pipe.
2039 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !stream
->has_data
) {
2043 readlen
= lttng_read(stream
->wait_fd
, &dummy
, 1);
2044 if (readlen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2051 /* Get the next subbuffer */
2052 err
= ustctl_get_next_subbuf(ustream
);
2055 * Populate metadata info if the existing info has
2056 * already been read.
2058 if (stream
->metadata_flag
) {
2059 ret
= commit_one_metadata_packet(stream
);
2063 ustctl_flush_buffer(stream
->ustream
, 1);
2067 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
2069 * This is a debug message even for single-threaded consumer,
2070 * because poll() have more relaxed criterions than get subbuf,
2071 * so get_subbuf may fail for short race windows where poll()
2072 * would issue wakeups.
2074 DBG("Reserving sub buffer failed (everything is normal, "
2075 "it is due to concurrency) [ret: %d]", err
);
2078 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
2080 if (!stream
->metadata_flag
) {
2081 index
.offset
= htobe64(stream
->out_fd_offset
);
2082 ret
= get_index_values(&index
, ustream
);
2090 /* Get the full padded subbuffer size */
2091 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
2094 /* Get subbuffer data size (without padding) */
2095 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
2098 /* Make sure we don't get a subbuffer size bigger than the padded */
2099 assert(len
>= subbuf_size
);
2101 padding
= len
- subbuf_size
;
2102 /* write the subbuffer to the tracefile */
2103 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
, &index
);
2105 * The mmap operation should write subbuf_size amount of data when network
2106 * streaming or the full padding (len) size when we are _not_ streaming.
2108 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
2109 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
2111 * Display the error but continue processing to try to release the
2112 * subbuffer. This is a DBG statement since any unexpected kill or
2113 * signal, the application gets unregistered, relayd gets closed or
2114 * anything that affects the buffer lifetime will trigger this error.
2115 * So, for the sake of the user, don't print this error since it can
2116 * happen and it is OK with the code flow.
2118 DBG("Error writing to tracefile "
2119 "(ret: %ld != len: %lu != subbuf_size: %lu)",
2120 ret
, len
, subbuf_size
);
2123 err
= ustctl_put_next_subbuf(ustream
);
2127 * This will consumer the byte on the wait_fd if and only if there is not
2128 * next subbuffer to be acquired.
2130 if (!stream
->metadata_flag
) {
2131 ret
= notify_if_more_data(stream
, ctx
);
2137 /* Write index if needed. */
2142 if (stream
->chan
->live_timer_interval
&& !stream
->metadata_flag
) {
2144 * In live, block until all the metadata is sent.
2146 pthread_mutex_lock(&stream
->metadata_timer_lock
);
2147 assert(!stream
->missed_metadata_flush
);
2148 stream
->waiting_on_metadata
= true;
2149 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2151 err
= consumer_stream_sync_metadata(ctx
, stream
->session_id
);
2153 pthread_mutex_lock(&stream
->metadata_timer_lock
);
2154 stream
->waiting_on_metadata
= false;
2155 if (stream
->missed_metadata_flush
) {
2156 stream
->missed_metadata_flush
= false;
2157 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2158 (void) consumer_flush_ust_index(stream
);
2160 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2168 assert(!stream
->metadata_flag
);
2169 err
= consumer_stream_write_index(stream
, &index
);
2179 * Called when a stream is created.
2181 * Return 0 on success or else a negative value.
2183 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
2189 /* Don't create anything if this is set for streaming. */
2190 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
) {
2191 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
2192 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
2193 stream
->uid
, stream
->gid
, NULL
);
2197 stream
->out_fd
= ret
;
2198 stream
->tracefile_size_current
= 0;
2200 if (!stream
->metadata_flag
) {
2201 ret
= index_create_file(stream
->chan
->pathname
,
2202 stream
->name
, stream
->uid
, stream
->gid
,
2203 stream
->chan
->tracefile_size
,
2204 stream
->tracefile_count_current
);
2208 stream
->index_fd
= ret
;
2218 * Check if data is still being extracted from the buffers for a specific
2219 * stream. Consumer data lock MUST be acquired before calling this function
2220 * and the stream lock.
2222 * Return 1 if the traced data are still getting read else 0 meaning that the
2223 * data is available for trace viewer reading.
2225 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
2230 assert(stream
->ustream
);
2232 DBG("UST consumer checking data pending");
2234 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
2239 if (stream
->chan
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
2240 uint64_t contiguous
, pushed
;
2242 /* Ease our life a bit. */
2243 contiguous
= stream
->chan
->metadata_cache
->max_offset
;
2244 pushed
= stream
->ust_metadata_pushed
;
2247 * We can simply check whether all contiguously available data
2248 * has been pushed to the ring buffer, since the push operation
2249 * is performed within get_next_subbuf(), and because both
2250 * get_next_subbuf() and put_next_subbuf() are issued atomically
2251 * thanks to the stream lock within
2252 * lttng_ustconsumer_read_subbuffer(). This basically means that
2253 * whetnever ust_metadata_pushed is incremented, the associated
2254 * metadata has been consumed from the metadata stream.
2256 DBG("UST consumer metadata pending check: contiguous %" PRIu64
" vs pushed %" PRIu64
,
2257 contiguous
, pushed
);
2258 assert(((int64_t) (contiguous
- pushed
)) >= 0);
2259 if ((contiguous
!= pushed
) ||
2260 (((int64_t) contiguous
- pushed
) > 0 || contiguous
== 0)) {
2261 ret
= 1; /* Data is pending */
2265 ret
= ustctl_get_next_subbuf(stream
->ustream
);
2268 * There is still data so let's put back this
2271 ret
= ustctl_put_subbuf(stream
->ustream
);
2273 ret
= 1; /* Data is pending */
2278 /* Data is NOT pending so ready to be read. */
2286 * Stop a given metadata channel timer if enabled and close the wait fd which
2287 * is the poll pipe of the metadata stream.
2289 * This MUST be called with the metadata channel acquired.
2291 void lttng_ustconsumer_close_metadata(struct lttng_consumer_channel
*metadata
)
2296 assert(metadata
->type
== CONSUMER_CHANNEL_TYPE_METADATA
);
2298 DBG("Closing metadata channel key %" PRIu64
, metadata
->key
);
2300 if (metadata
->switch_timer_enabled
== 1) {
2301 consumer_timer_switch_stop(metadata
);
2304 if (!metadata
->metadata_stream
) {
2309 * Closing write side so the thread monitoring the stream wakes up if any
2310 * and clean the metadata stream.
2312 if (metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] >= 0) {
2313 ret
= close(metadata
->metadata_stream
->ust_metadata_poll_pipe
[1]);
2315 PERROR("closing metadata pipe write side");
2317 metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] = -1;
2325 * Close every metadata stream wait fd of the metadata hash table. This
2326 * function MUST be used very carefully so not to run into a race between the
2327 * metadata thread handling streams and this function closing their wait fd.
2329 * For UST, this is used when the session daemon hangs up. Its the metadata
2330 * producer so calling this is safe because we are assured that no state change
2331 * can occur in the metadata thread for the streams in the hash table.
2333 void lttng_ustconsumer_close_all_metadata(struct lttng_ht
*metadata_ht
)
2335 struct lttng_ht_iter iter
;
2336 struct lttng_consumer_stream
*stream
;
2338 assert(metadata_ht
);
2339 assert(metadata_ht
->ht
);
2341 DBG("UST consumer closing all metadata streams");
2344 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
2347 health_code_update();
2349 pthread_mutex_lock(&stream
->chan
->lock
);
2350 lttng_ustconsumer_close_metadata(stream
->chan
);
2351 pthread_mutex_unlock(&stream
->chan
->lock
);
2357 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
2361 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
2363 ERR("Unable to close wakeup fd");
2368 * Please refer to consumer-timer.c before adding any lock within this
2369 * function or any of its callees. Timers have a very strict locking
2370 * semantic with respect to teardown. Failure to respect this semantic
2371 * introduces deadlocks.
2373 * DON'T hold the metadata lock when calling this function, else this
2374 * can cause deadlock involving consumer awaiting for metadata to be
2375 * pushed out due to concurrent interaction with the session daemon.
2377 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
2378 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
2380 struct lttcomm_metadata_request_msg request
;
2381 struct lttcomm_consumer_msg msg
;
2382 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
2383 uint64_t len
, key
, offset
;
2387 assert(channel
->metadata_cache
);
2389 memset(&request
, 0, sizeof(request
));
2391 /* send the metadata request to sessiond */
2392 switch (consumer_data
.type
) {
2393 case LTTNG_CONSUMER64_UST
:
2394 request
.bits_per_long
= 64;
2396 case LTTNG_CONSUMER32_UST
:
2397 request
.bits_per_long
= 32;
2400 request
.bits_per_long
= 0;
2404 request
.session_id
= channel
->session_id
;
2405 request
.session_id_per_pid
= channel
->session_id_per_pid
;
2407 * Request the application UID here so the metadata of that application can
2408 * be sent back. The channel UID corresponds to the user UID of the session
2409 * used for the rights on the stream file(s).
2411 request
.uid
= channel
->ust_app_uid
;
2412 request
.key
= channel
->key
;
2414 DBG("Sending metadata request to sessiond, session id %" PRIu64
2415 ", per-pid %" PRIu64
", app UID %u and channek key %" PRIu64
,
2416 request
.session_id
, request
.session_id_per_pid
, request
.uid
,
2419 pthread_mutex_lock(&ctx
->metadata_socket_lock
);
2421 health_code_update();
2423 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
2426 ERR("Asking metadata to sessiond");
2430 health_code_update();
2432 /* Receive the metadata from sessiond */
2433 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
2435 if (ret
!= sizeof(msg
)) {
2436 DBG("Consumer received unexpected message size %d (expects %zu)",
2438 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
2440 * The ret value might 0 meaning an orderly shutdown but this is ok
2441 * since the caller handles this.
2446 health_code_update();
2448 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
2449 /* No registry found */
2450 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2454 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
2455 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
2460 len
= msg
.u
.push_metadata
.len
;
2461 key
= msg
.u
.push_metadata
.key
;
2462 offset
= msg
.u
.push_metadata
.target_offset
;
2464 assert(key
== channel
->key
);
2466 DBG("No new metadata to receive for key %" PRIu64
, key
);
2469 health_code_update();
2471 /* Tell session daemon we are ready to receive the metadata. */
2472 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2473 LTTCOMM_CONSUMERD_SUCCESS
);
2474 if (ret
< 0 || len
== 0) {
2476 * Somehow, the session daemon is not responding anymore or there is
2477 * nothing to receive.
2482 health_code_update();
2484 ret
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
2485 key
, offset
, len
, channel
, timer
, wait
);
2488 * Only send the status msg if the sessiond is alive meaning a positive
2491 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret
);
2496 health_code_update();
2498 pthread_mutex_unlock(&ctx
->metadata_socket_lock
);
2503 * Return the ustctl call for the get stream id.
2505 int lttng_ustconsumer_get_stream_id(struct lttng_consumer_stream
*stream
,
2506 uint64_t *stream_id
)
2511 return ustctl_get_stream_id(stream
->ustream
, stream_id
);