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.
22 #include <lttng/ust-ctl.h>
28 #include <sys/socket.h>
30 #include <sys/types.h>
33 #include <urcu/list.h>
36 #include <bin/lttng-consumerd/health-consumerd.h>
37 #include <common/common.h>
38 #include <common/sessiond-comm/sessiond-comm.h>
39 #include <common/relayd/relayd.h>
40 #include <common/compat/fcntl.h>
41 #include <common/compat/endian.h>
42 #include <common/consumer-metadata-cache.h>
43 #include <common/consumer-stream.h>
44 #include <common/consumer-timer.h>
45 #include <common/utils.h>
46 #include <common/index/index.h>
48 #include "ust-consumer.h"
50 extern struct lttng_consumer_global_data consumer_data
;
51 extern int consumer_poll_timeout
;
52 extern volatile int consumer_quit
;
55 * Free channel object and all streams associated with it. This MUST be used
56 * only and only if the channel has _NEVER_ been added to the global channel
59 static void destroy_channel(struct lttng_consumer_channel
*channel
)
61 struct lttng_consumer_stream
*stream
, *stmp
;
65 DBG("UST consumer cleaning stream list");
67 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
72 cds_list_del(&stream
->send_node
);
73 ustctl_destroy_stream(stream
->ustream
);
78 * If a channel is available meaning that was created before the streams
82 lttng_ustconsumer_del_channel(channel
);
84 /* Try to rmdir all directories under shm_path root. */
85 if (channel
->root_shm_path
[0]) {
86 (void) utils_recursive_rmdir(channel
->root_shm_path
);
92 * Add channel to internal consumer state.
94 * Returns 0 on success or else a negative value.
96 static int add_channel(struct lttng_consumer_channel
*channel
,
97 struct lttng_consumer_local_data
*ctx
)
104 if (ctx
->on_recv_channel
!= NULL
) {
105 ret
= ctx
->on_recv_channel(channel
);
107 ret
= consumer_add_channel(channel
, ctx
);
108 } else if (ret
< 0) {
109 /* Most likely an ENOMEM. */
110 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
114 ret
= consumer_add_channel(channel
, ctx
);
117 DBG("UST consumer channel added (key: %" PRIu64
")", channel
->key
);
124 * Allocate and return a consumer channel object.
126 static struct lttng_consumer_channel
*allocate_channel(uint64_t session_id
,
127 const char *pathname
, const char *name
, uid_t uid
, gid_t gid
,
128 uint64_t relayd_id
, uint64_t key
, enum lttng_event_output output
,
129 uint64_t tracefile_size
, uint64_t tracefile_count
,
130 uint64_t session_id_per_pid
, unsigned int monitor
,
131 unsigned int live_timer_interval
,
132 const char *root_shm_path
, const char *shm_path
)
137 return consumer_allocate_channel(key
, session_id
, pathname
, name
, uid
,
138 gid
, relayd_id
, output
, tracefile_size
,
139 tracefile_count
, session_id_per_pid
, monitor
,
140 live_timer_interval
, root_shm_path
, shm_path
);
144 * Allocate and return a consumer stream object. If _alloc_ret is not NULL, the
145 * error value if applicable is set in it else it is kept untouched.
147 * Return NULL on error else the newly allocated stream object.
149 static struct lttng_consumer_stream
*allocate_stream(int cpu
, int key
,
150 struct lttng_consumer_channel
*channel
,
151 struct lttng_consumer_local_data
*ctx
, int *_alloc_ret
)
154 struct lttng_consumer_stream
*stream
= NULL
;
159 stream
= consumer_allocate_stream(channel
->key
,
161 LTTNG_CONSUMER_ACTIVE_STREAM
,
171 if (stream
== NULL
) {
175 * We could not find the channel. Can happen if cpu hotplug
176 * happens while tearing down.
178 DBG3("Could not find channel");
183 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
189 stream
->chan
= channel
;
193 *_alloc_ret
= alloc_ret
;
199 * Send the given stream pointer to the corresponding thread.
201 * Returns 0 on success else a negative value.
203 static int send_stream_to_thread(struct lttng_consumer_stream
*stream
,
204 struct lttng_consumer_local_data
*ctx
)
207 struct lttng_pipe
*stream_pipe
;
209 /* Get the right pipe where the stream will be sent. */
210 if (stream
->metadata_flag
) {
211 ret
= consumer_add_metadata_stream(stream
);
213 ERR("Consumer add metadata stream %" PRIu64
" failed.",
217 stream_pipe
= ctx
->consumer_metadata_pipe
;
219 ret
= consumer_add_data_stream(stream
);
221 ERR("Consumer add stream %" PRIu64
" failed.",
225 stream_pipe
= ctx
->consumer_data_pipe
;
229 * From this point on, the stream's ownership has been moved away from
230 * the channel and becomes globally visible.
232 stream
->globally_visible
= 1;
234 ret
= lttng_pipe_write(stream_pipe
, &stream
, sizeof(stream
));
236 ERR("Consumer write %s stream to pipe %d",
237 stream
->metadata_flag
? "metadata" : "data",
238 lttng_pipe_get_writefd(stream_pipe
));
239 if (stream
->metadata_flag
) {
240 consumer_del_stream_for_metadata(stream
);
242 consumer_del_stream_for_data(stream
);
250 * Create streams for the given channel using liblttng-ust-ctl.
252 * Return 0 on success else a negative value.
254 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
255 struct lttng_consumer_local_data
*ctx
)
258 struct ustctl_consumer_stream
*ustream
;
259 struct lttng_consumer_stream
*stream
;
265 * While a stream is available from ustctl. When NULL is returned, we've
266 * reached the end of the possible stream for the channel.
268 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
270 int ust_metadata_pipe
[2];
272 health_code_update();
274 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& channel
->monitor
) {
275 ret
= utils_create_pipe_cloexec_nonblock(ust_metadata_pipe
);
277 ERR("Create ust metadata poll pipe");
280 wait_fd
= ust_metadata_pipe
[0];
282 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
285 /* Allocate consumer stream object. */
286 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
290 stream
->ustream
= ustream
;
292 * Store it so we can save multiple function calls afterwards since
293 * this value is used heavily in the stream threads. This is UST
294 * specific so this is why it's done after allocation.
296 stream
->wait_fd
= wait_fd
;
299 * Increment channel refcount since the channel reference has now been
300 * assigned in the allocation process above.
302 if (stream
->chan
->monitor
) {
303 uatomic_inc(&stream
->chan
->refcount
);
307 * Order is important this is why a list is used. On error, the caller
308 * should clean this list.
310 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
312 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
313 &stream
->max_sb_size
);
315 ERR("ustctl_get_max_subbuf_size failed for stream %s",
320 /* Do actions once stream has been received. */
321 if (ctx
->on_recv_stream
) {
322 ret
= ctx
->on_recv_stream(stream
);
328 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
329 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
331 /* Set next CPU stream. */
332 channel
->streams
.count
= ++cpu
;
334 /* Keep stream reference when creating metadata. */
335 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
336 channel
->metadata_stream
= stream
;
337 stream
->ust_metadata_poll_pipe
[0] = ust_metadata_pipe
[0];
338 stream
->ust_metadata_poll_pipe
[1] = ust_metadata_pipe
[1];
350 * Create an UST channel with the given attributes and send it to the session
351 * daemon using the ust ctl API.
353 * Return 0 on success or else a negative value.
355 static int create_ust_channel(struct ustctl_consumer_channel_attr
*attr
,
356 struct ustctl_consumer_channel
**chanp
)
359 struct ustctl_consumer_channel
*channel
;
364 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
365 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
366 "switch_timer_interval: %u, read_timer_interval: %u, "
367 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
368 attr
->num_subbuf
, attr
->switch_timer_interval
,
369 attr
->read_timer_interval
, attr
->output
, attr
->type
);
371 channel
= ustctl_create_channel(attr
);
386 * Send a single given stream to the session daemon using the sock.
388 * Return 0 on success else a negative value.
390 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
397 DBG("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
399 /* Send stream to session daemon. */
400 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
410 * Send channel to sessiond.
412 * Return 0 on success or else a negative value.
414 static int send_sessiond_channel(int sock
,
415 struct lttng_consumer_channel
*channel
,
416 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
418 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
419 struct lttng_consumer_stream
*stream
;
420 uint64_t net_seq_idx
= -1ULL;
426 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
428 if (channel
->relayd_id
!= (uint64_t) -1ULL) {
429 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
431 health_code_update();
433 /* Try to send the stream to the relayd if one is available. */
434 ret
= consumer_send_relayd_stream(stream
, stream
->chan
->pathname
);
437 * Flag that the relayd was the problem here probably due to a
438 * communicaton error on the socket.
443 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
445 if (net_seq_idx
== -1ULL) {
446 net_seq_idx
= stream
->net_seq_idx
;
451 /* Inform sessiond that we are about to send channel and streams. */
452 ret
= consumer_send_status_msg(sock
, ret_code
);
453 if (ret
< 0 || ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
455 * Either the session daemon is not responding or the relayd died so we
461 /* Send channel to sessiond. */
462 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
467 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
472 /* The channel was sent successfully to the sessiond at this point. */
473 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
475 health_code_update();
477 /* Send stream to session daemon. */
478 ret
= send_sessiond_stream(sock
, stream
);
484 /* Tell sessiond there is no more stream. */
485 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
490 DBG("UST consumer NULL stream sent to sessiond");
495 if (ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
502 * Creates a channel and streams and add the channel it to the channel internal
503 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
506 * Return 0 on success or else, a negative value is returned and the channel
507 * MUST be destroyed by consumer_del_channel().
509 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
510 struct lttng_consumer_channel
*channel
,
511 struct ustctl_consumer_channel_attr
*attr
)
520 * This value is still used by the kernel consumer since for the kernel,
521 * the stream ownership is not IN the consumer so we need to have the
522 * number of left stream that needs to be initialized so we can know when
523 * to delete the channel (see consumer.c).
525 * As for the user space tracer now, the consumer creates and sends the
526 * stream to the session daemon which only sends them to the application
527 * once every stream of a channel is received making this value useless
528 * because we they will be added to the poll thread before the application
529 * receives them. This ensures that a stream can not hang up during
530 * initilization of a channel.
532 channel
->nb_init_stream_left
= 0;
534 /* The reply msg status is handled in the following call. */
535 ret
= create_ust_channel(attr
, &channel
->uchan
);
540 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
543 * For the snapshots (no monitor), we create the metadata streams
544 * on demand, not during the channel creation.
546 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& !channel
->monitor
) {
551 /* Open all streams for this channel. */
552 ret
= create_ust_streams(channel
, ctx
);
562 * Send all stream of a channel to the right thread handling it.
564 * On error, return a negative value else 0 on success.
566 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
567 struct lttng_consumer_local_data
*ctx
)
570 struct lttng_consumer_stream
*stream
, *stmp
;
575 /* Send streams to the corresponding thread. */
576 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
579 health_code_update();
581 /* Sending the stream to the thread. */
582 ret
= send_stream_to_thread(stream
, ctx
);
585 * If we are unable to send the stream to the thread, there is
586 * a big problem so just stop everything.
588 /* Remove node from the channel stream list. */
589 cds_list_del(&stream
->send_node
);
593 /* Remove node from the channel stream list. */
594 cds_list_del(&stream
->send_node
);
603 * Flush channel's streams using the given key to retrieve the channel.
605 * Return 0 on success else an LTTng error code.
607 static int flush_channel(uint64_t chan_key
)
610 struct lttng_consumer_channel
*channel
;
611 struct lttng_consumer_stream
*stream
;
613 struct lttng_ht_iter iter
;
615 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
618 channel
= consumer_find_channel(chan_key
);
620 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
621 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
625 ht
= consumer_data
.stream_per_chan_id_ht
;
627 /* For each stream of the channel id, flush it. */
628 cds_lfht_for_each_entry_duplicate(ht
->ht
,
629 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
630 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
632 health_code_update();
634 ustctl_flush_buffer(stream
->ustream
, 1);
642 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
643 * RCU read side lock MUST be acquired before calling this function.
645 * Return 0 on success else an LTTng error code.
647 static int close_metadata(uint64_t chan_key
)
650 struct lttng_consumer_channel
*channel
;
652 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
654 channel
= consumer_find_channel(chan_key
);
657 * This is possible if the metadata thread has issue a delete because
658 * the endpoint point of the stream hung up. There is no way the
659 * session daemon can know about it thus use a DBG instead of an actual
662 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
663 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
667 pthread_mutex_lock(&consumer_data
.lock
);
668 pthread_mutex_lock(&channel
->lock
);
670 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
674 lttng_ustconsumer_close_metadata(channel
);
677 pthread_mutex_unlock(&channel
->lock
);
678 pthread_mutex_unlock(&consumer_data
.lock
);
684 * RCU read side lock MUST be acquired before calling this function.
686 * Return 0 on success else an LTTng error code.
688 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
691 struct lttng_consumer_channel
*metadata
;
693 DBG("UST consumer setup metadata key %" PRIu64
, key
);
695 metadata
= consumer_find_channel(key
);
697 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
698 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
703 * In no monitor mode, the metadata channel has no stream(s) so skip the
704 * ownership transfer to the metadata thread.
706 if (!metadata
->monitor
) {
707 DBG("Metadata channel in no monitor");
713 * Send metadata stream to relayd if one available. Availability is
714 * known if the stream is still in the list of the channel.
716 if (cds_list_empty(&metadata
->streams
.head
)) {
717 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
718 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
719 goto error_no_stream
;
722 /* Send metadata stream to relayd if needed. */
723 if (metadata
->metadata_stream
->net_seq_idx
!= (uint64_t) -1ULL) {
724 ret
= consumer_send_relayd_stream(metadata
->metadata_stream
,
727 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
730 ret
= consumer_send_relayd_streams_sent(
731 metadata
->metadata_stream
->net_seq_idx
);
733 ret
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
738 ret
= send_streams_to_thread(metadata
, ctx
);
741 * If we are unable to send the stream to the thread, there is
742 * a big problem so just stop everything.
744 ret
= LTTCOMM_CONSUMERD_FATAL
;
747 /* List MUST be empty after or else it could be reused. */
748 assert(cds_list_empty(&metadata
->streams
.head
));
755 * Delete metadata channel on error. At this point, the metadata stream can
756 * NOT be monitored by the metadata thread thus having the guarantee that
757 * the stream is still in the local stream list of the channel. This call
758 * will make sure to clean that list.
760 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
761 cds_list_del(&metadata
->metadata_stream
->send_node
);
762 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
);
797 health_code_update();
800 * Ask the sessiond if we have new metadata waiting and update the
801 * consumer metadata cache.
803 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
, 0, 1);
808 health_code_update();
811 * The metadata stream is NOT created in no monitor mode when the channel
812 * is created on a sessiond ask channel command.
814 ret
= create_ust_streams(metadata_channel
, ctx
);
819 metadata_stream
= metadata_channel
->metadata_stream
;
820 assert(metadata_stream
);
822 if (relayd_id
!= (uint64_t) -1ULL) {
823 metadata_stream
->net_seq_idx
= relayd_id
;
824 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
829 ret
= utils_create_stream_file(path
, metadata_stream
->name
,
830 metadata_stream
->chan
->tracefile_size
,
831 metadata_stream
->tracefile_count_current
,
832 metadata_stream
->uid
, metadata_stream
->gid
, NULL
);
836 metadata_stream
->out_fd
= ret
;
837 metadata_stream
->tracefile_size_current
= 0;
841 health_code_update();
843 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
);
851 * Clean up the stream completly because the next snapshot will use a new
854 consumer_stream_destroy(metadata_stream
, NULL
);
855 cds_list_del(&metadata_stream
->send_node
);
856 metadata_channel
->metadata_stream
= NULL
;
864 * Take a snapshot of all the stream of a channel.
866 * Returns 0 on success, < 0 on error
868 static int snapshot_channel(uint64_t key
, char *path
, uint64_t relayd_id
,
869 uint64_t nb_packets_per_stream
, struct lttng_consumer_local_data
*ctx
)
872 unsigned use_relayd
= 0;
873 unsigned long consumed_pos
, produced_pos
;
874 struct lttng_consumer_channel
*channel
;
875 struct lttng_consumer_stream
*stream
;
882 if (relayd_id
!= (uint64_t) -1ULL) {
886 channel
= consumer_find_channel(key
);
888 ERR("UST snapshot channel not found for key %" PRIu64
, key
);
892 assert(!channel
->monitor
);
893 DBG("UST consumer snapshot channel %" PRIu64
, key
);
895 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
897 health_code_update();
899 /* Lock stream because we are about to change its state. */
900 pthread_mutex_lock(&stream
->lock
);
901 stream
->net_seq_idx
= relayd_id
;
904 ret
= consumer_send_relayd_stream(stream
, path
);
909 ret
= utils_create_stream_file(path
, stream
->name
,
910 stream
->chan
->tracefile_size
,
911 stream
->tracefile_count_current
,
912 stream
->uid
, stream
->gid
, NULL
);
916 stream
->out_fd
= ret
;
917 stream
->tracefile_size_current
= 0;
919 DBG("UST consumer snapshot stream %s/%s (%" PRIu64
")", path
,
920 stream
->name
, stream
->key
);
922 if (relayd_id
!= -1ULL) {
923 ret
= consumer_send_relayd_streams_sent(relayd_id
);
929 ustctl_flush_buffer(stream
->ustream
, 1);
931 ret
= lttng_ustconsumer_take_snapshot(stream
);
933 ERR("Taking UST snapshot");
937 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
939 ERR("Produced UST snapshot position");
943 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
945 ERR("Consumerd UST snapshot position");
950 * The original value is sent back if max stream size is larger than
951 * the possible size of the snapshot. Also, we assume that the session
952 * daemon should never send a maximum stream size that is lower than
955 consumed_pos
= consumer_get_consume_start_pos(consumed_pos
,
956 produced_pos
, nb_packets_per_stream
,
957 stream
->max_sb_size
);
959 while (consumed_pos
< produced_pos
) {
961 unsigned long len
, padded_len
;
963 health_code_update();
965 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
967 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
969 if (ret
!= -EAGAIN
) {
970 PERROR("ustctl_get_subbuf snapshot");
971 goto error_close_stream
;
973 DBG("UST consumer get subbuf failed. Skipping it.");
974 consumed_pos
+= stream
->max_sb_size
;
978 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
980 ERR("Snapshot ustctl_get_subbuf_size");
981 goto error_put_subbuf
;
984 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
986 ERR("Snapshot ustctl_get_padded_subbuf_size");
987 goto error_put_subbuf
;
990 read_len
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, len
,
991 padded_len
- len
, NULL
);
993 if (read_len
!= len
) {
995 goto error_put_subbuf
;
998 if (read_len
!= padded_len
) {
1000 goto error_put_subbuf
;
1004 ret
= ustctl_put_subbuf(stream
->ustream
);
1006 ERR("Snapshot ustctl_put_subbuf");
1007 goto error_close_stream
;
1009 consumed_pos
+= stream
->max_sb_size
;
1012 /* Simply close the stream so we can use it on the next snapshot. */
1013 consumer_stream_close(stream
);
1014 pthread_mutex_unlock(&stream
->lock
);
1021 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
1022 ERR("Snapshot ustctl_put_subbuf");
1025 consumer_stream_close(stream
);
1027 pthread_mutex_unlock(&stream
->lock
);
1034 * Receive the metadata updates from the sessiond.
1036 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
1037 uint64_t len
, struct lttng_consumer_channel
*channel
,
1038 int timer
, int wait
)
1040 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1043 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
1045 metadata_str
= zmalloc(len
* sizeof(char));
1046 if (!metadata_str
) {
1047 PERROR("zmalloc metadata string");
1048 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
1052 health_code_update();
1054 /* Receive metadata string. */
1055 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1057 /* Session daemon is dead so return gracefully. */
1062 health_code_update();
1064 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1065 ret
= consumer_metadata_cache_write(channel
, offset
, len
, metadata_str
);
1067 /* Unable to handle metadata. Notify session daemon. */
1068 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1070 * Skip metadata flush on write error since the offset and len might
1071 * not have been updated which could create an infinite loop below when
1072 * waiting for the metadata cache to be flushed.
1074 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1077 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1082 while (consumer_metadata_cache_flushed(channel
, offset
+ len
, timer
)) {
1083 DBG("Waiting for metadata to be flushed");
1085 health_code_update();
1087 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1097 * Receive command from session daemon and process it.
1099 * Return 1 on success else a negative value or 0.
1101 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1102 int sock
, struct pollfd
*consumer_sockpoll
)
1105 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1106 struct lttcomm_consumer_msg msg
;
1107 struct lttng_consumer_channel
*channel
= NULL
;
1109 health_code_update();
1111 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1112 if (ret
!= sizeof(msg
)) {
1113 DBG("Consumer received unexpected message size %zd (expects %zu)",
1116 * The ret value might 0 meaning an orderly shutdown but this is ok
1117 * since the caller handles this.
1120 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1126 health_code_update();
1129 assert(msg
.cmd_type
!= LTTNG_CONSUMER_STOP
);
1131 health_code_update();
1133 /* relayd needs RCU read-side lock */
1136 switch (msg
.cmd_type
) {
1137 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1139 /* Session daemon status message are handled in the following call. */
1140 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1141 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1142 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
,
1143 msg
.u
.relayd_sock
.relayd_session_id
);
1146 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1148 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1149 struct consumer_relayd_sock_pair
*relayd
;
1151 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1153 /* Get relayd reference if exists. */
1154 relayd
= consumer_find_relayd(index
);
1155 if (relayd
== NULL
) {
1156 DBG("Unable to find relayd %" PRIu64
, index
);
1157 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
1161 * Each relayd socket pair has a refcount of stream attached to it
1162 * which tells if the relayd is still active or not depending on the
1165 * This will set the destroy flag of the relayd object and destroy it
1166 * if the refcount reaches zero when called.
1168 * The destroy can happen either here or when a stream fd hangs up.
1171 consumer_flag_relayd_for_destroy(relayd
);
1174 goto end_msg_sessiond
;
1176 case LTTNG_CONSUMER_UPDATE_STREAM
:
1181 case LTTNG_CONSUMER_DATA_PENDING
:
1183 int ret
, is_data_pending
;
1184 uint64_t id
= msg
.u
.data_pending
.session_id
;
1186 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1188 is_data_pending
= consumer_data_pending(id
);
1190 /* Send back returned value to session daemon */
1191 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1192 sizeof(is_data_pending
));
1194 DBG("Error when sending the data pending ret code: %d", ret
);
1199 * No need to send back a status message since the data pending
1200 * returned value is the response.
1204 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1207 struct ustctl_consumer_channel_attr attr
;
1209 /* Create a plain object and reserve a channel key. */
1210 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
1211 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
1212 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
1213 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
1214 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1215 msg
.u
.ask_channel
.tracefile_size
,
1216 msg
.u
.ask_channel
.tracefile_count
,
1217 msg
.u
.ask_channel
.session_id_per_pid
,
1218 msg
.u
.ask_channel
.monitor
,
1219 msg
.u
.ask_channel
.live_timer_interval
,
1220 msg
.u
.ask_channel
.root_shm_path
,
1221 msg
.u
.ask_channel
.shm_path
);
1223 goto end_channel_error
;
1227 * Assign UST application UID to the channel. This value is ignored for
1228 * per PID buffers. This is specific to UST thus setting this after the
1231 channel
->ust_app_uid
= msg
.u
.ask_channel
.ust_app_uid
;
1233 /* Build channel attributes from received message. */
1234 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1235 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1236 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1237 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1238 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1239 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1240 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1241 strncpy(attr
.shm_path
, channel
->shm_path
,
1242 sizeof(attr
.shm_path
));
1243 attr
.shm_path
[sizeof(attr
.shm_path
) - 1] = '\0';
1245 /* Match channel buffer type to the UST abi. */
1246 switch (msg
.u
.ask_channel
.output
) {
1247 case LTTNG_EVENT_MMAP
:
1249 attr
.output
= LTTNG_UST_MMAP
;
1253 /* Translate and save channel type. */
1254 switch (msg
.u
.ask_channel
.type
) {
1255 case LTTNG_UST_CHAN_PER_CPU
:
1256 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1257 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1259 * Set refcount to 1 for owner. Below, we will
1260 * pass ownership to the
1261 * consumer_thread_channel_poll() thread.
1263 channel
->refcount
= 1;
1265 case LTTNG_UST_CHAN_METADATA
:
1266 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1267 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1274 health_code_update();
1276 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
1278 goto end_channel_error
;
1281 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1282 ret
= consumer_metadata_cache_allocate(channel
);
1284 ERR("Allocating metadata cache");
1285 goto end_channel_error
;
1287 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1288 attr
.switch_timer_interval
= 0;
1290 consumer_timer_live_start(channel
,
1291 msg
.u
.ask_channel
.live_timer_interval
);
1294 health_code_update();
1297 * Add the channel to the internal state AFTER all streams were created
1298 * and successfully sent to session daemon. This way, all streams must
1299 * be ready before this channel is visible to the threads.
1300 * If add_channel succeeds, ownership of the channel is
1301 * passed to consumer_thread_channel_poll().
1303 ret
= add_channel(channel
, ctx
);
1305 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1306 if (channel
->switch_timer_enabled
== 1) {
1307 consumer_timer_switch_stop(channel
);
1309 consumer_metadata_cache_destroy(channel
);
1311 if (channel
->live_timer_enabled
== 1) {
1312 consumer_timer_live_stop(channel
);
1314 goto end_channel_error
;
1317 health_code_update();
1320 * Channel and streams are now created. Inform the session daemon that
1321 * everything went well and should wait to receive the channel and
1322 * streams with ustctl API.
1324 ret
= consumer_send_status_channel(sock
, channel
);
1327 * There is probably a problem on the socket.
1334 case LTTNG_CONSUMER_GET_CHANNEL
:
1336 int ret
, relayd_err
= 0;
1337 uint64_t key
= msg
.u
.get_channel
.key
;
1338 struct lttng_consumer_channel
*channel
;
1340 channel
= consumer_find_channel(key
);
1342 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1343 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1344 goto end_msg_sessiond
;
1347 health_code_update();
1349 /* Send everything to sessiond. */
1350 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1354 * We were unable to send to the relayd the stream so avoid
1355 * sending back a fatal error to the thread since this is OK
1356 * and the consumer can continue its work. The above call
1357 * has sent the error status message to the sessiond.
1362 * The communicaton was broken hence there is a bad state between
1363 * the consumer and sessiond so stop everything.
1368 health_code_update();
1371 * In no monitor mode, the streams ownership is kept inside the channel
1372 * so don't send them to the data thread.
1374 if (!channel
->monitor
) {
1375 goto end_msg_sessiond
;
1378 ret
= send_streams_to_thread(channel
, ctx
);
1381 * If we are unable to send the stream to the thread, there is
1382 * a big problem so just stop everything.
1386 /* List MUST be empty after or else it could be reused. */
1387 assert(cds_list_empty(&channel
->streams
.head
));
1388 goto end_msg_sessiond
;
1390 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1392 uint64_t key
= msg
.u
.destroy_channel
.key
;
1395 * Only called if streams have not been sent to stream
1396 * manager thread. However, channel has been sent to
1397 * channel manager thread.
1399 notify_thread_del_channel(ctx
, key
);
1400 goto end_msg_sessiond
;
1402 case LTTNG_CONSUMER_CLOSE_METADATA
:
1406 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1411 goto end_msg_sessiond
;
1413 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1417 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1422 goto end_msg_sessiond
;
1424 case LTTNG_CONSUMER_PUSH_METADATA
:
1427 uint64_t len
= msg
.u
.push_metadata
.len
;
1428 uint64_t key
= msg
.u
.push_metadata
.key
;
1429 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1430 struct lttng_consumer_channel
*channel
;
1432 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1435 channel
= consumer_find_channel(key
);
1438 * This is possible if the metadata creation on the consumer side
1439 * is in flight vis-a-vis a concurrent push metadata from the
1440 * session daemon. Simply return that the channel failed and the
1441 * session daemon will handle that message correctly considering
1442 * that this race is acceptable thus the DBG() statement here.
1444 DBG("UST consumer push metadata %" PRIu64
" not found", key
);
1445 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1446 goto end_msg_sessiond
;
1449 health_code_update();
1451 /* Tell session daemon we are ready to receive the metadata. */
1452 ret
= consumer_send_status_msg(sock
, LTTCOMM_CONSUMERD_SUCCESS
);
1454 /* Somehow, the session daemon is not responding anymore. */
1458 health_code_update();
1460 /* Wait for more data. */
1461 health_poll_entry();
1462 ret
= lttng_consumer_poll_socket(consumer_sockpoll
);
1468 health_code_update();
1470 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1471 len
, channel
, 0, 1);
1473 /* error receiving from sessiond */
1477 goto end_msg_sessiond
;
1480 case LTTNG_CONSUMER_SETUP_METADATA
:
1484 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1488 goto end_msg_sessiond
;
1490 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1492 if (msg
.u
.snapshot_channel
.metadata
) {
1493 ret
= snapshot_metadata(msg
.u
.snapshot_channel
.key
,
1494 msg
.u
.snapshot_channel
.pathname
,
1495 msg
.u
.snapshot_channel
.relayd_id
,
1498 ERR("Snapshot metadata failed");
1499 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1502 ret
= snapshot_channel(msg
.u
.snapshot_channel
.key
,
1503 msg
.u
.snapshot_channel
.pathname
,
1504 msg
.u
.snapshot_channel
.relayd_id
,
1505 msg
.u
.snapshot_channel
.nb_packets_per_stream
,
1508 ERR("Snapshot channel failed");
1509 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1513 health_code_update();
1514 ret
= consumer_send_status_msg(sock
, ret_code
);
1516 /* Somehow, the session daemon is not responding anymore. */
1519 health_code_update();
1529 health_code_update();
1532 * Return 1 to indicate success since the 0 value can be a socket
1533 * shutdown during the recv() or send() call.
1539 * The returned value here is not useful since either way we'll return 1 to
1540 * the caller because the session daemon socket management is done
1541 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1543 ret
= consumer_send_status_msg(sock
, ret_code
);
1549 health_code_update();
1555 * Free channel here since no one has a reference to it. We don't
1556 * free after that because a stream can store this pointer.
1558 destroy_channel(channel
);
1560 /* We have to send a status channel message indicating an error. */
1561 ret
= consumer_send_status_channel(sock
, NULL
);
1563 /* Stop everything if session daemon can not be notified. */
1568 health_code_update();
1573 /* This will issue a consumer stop. */
1578 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1579 * compiled out, we isolate it in this library.
1581 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1585 assert(stream
->ustream
);
1587 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1591 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1592 * compiled out, we isolate it in this library.
1594 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1597 assert(stream
->ustream
);
1599 return ustctl_get_mmap_base(stream
->ustream
);
1603 * Take a snapshot for a specific fd
1605 * Returns 0 on success, < 0 on error
1607 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1610 assert(stream
->ustream
);
1612 return ustctl_snapshot(stream
->ustream
);
1616 * Get the produced position
1618 * Returns 0 on success, < 0 on error
1620 int lttng_ustconsumer_get_produced_snapshot(
1621 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1624 assert(stream
->ustream
);
1627 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1631 * Get the consumed position
1633 * Returns 0 on success, < 0 on error
1635 int lttng_ustconsumer_get_consumed_snapshot(
1636 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1639 assert(stream
->ustream
);
1642 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
1645 void lttng_ustconsumer_flush_buffer(struct lttng_consumer_stream
*stream
,
1649 assert(stream
->ustream
);
1651 ustctl_flush_buffer(stream
->ustream
, producer
);
1654 int lttng_ustconsumer_get_current_timestamp(
1655 struct lttng_consumer_stream
*stream
, uint64_t *ts
)
1658 assert(stream
->ustream
);
1661 return ustctl_get_current_timestamp(stream
->ustream
, ts
);
1665 * Called when the stream signal the consumer that it has hang up.
1667 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1670 assert(stream
->ustream
);
1672 ustctl_flush_buffer(stream
->ustream
, 0);
1673 stream
->hangup_flush_done
= 1;
1676 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1679 assert(chan
->uchan
);
1681 if (chan
->switch_timer_enabled
== 1) {
1682 consumer_timer_switch_stop(chan
);
1684 consumer_metadata_cache_destroy(chan
);
1685 ustctl_destroy_channel(chan
->uchan
);
1686 /* Try to rmdir all directories under shm_path root. */
1687 if (chan
->root_shm_path
[0]) {
1688 (void) utils_recursive_rmdir(chan
->root_shm_path
);
1692 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
1695 assert(stream
->ustream
);
1697 if (stream
->chan
->switch_timer_enabled
== 1) {
1698 consumer_timer_switch_stop(stream
->chan
);
1700 ustctl_destroy_stream(stream
->ustream
);
1703 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream
*stream
)
1706 assert(stream
->ustream
);
1708 return ustctl_stream_get_wakeup_fd(stream
->ustream
);
1711 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream
*stream
)
1714 assert(stream
->ustream
);
1716 return ustctl_stream_close_wakeup_fd(stream
->ustream
);
1720 * Populate index values of a UST stream. Values are set in big endian order.
1722 * Return 0 on success or else a negative value.
1724 static int get_index_values(struct ctf_packet_index
*index
,
1725 struct ustctl_consumer_stream
*ustream
)
1729 ret
= ustctl_get_timestamp_begin(ustream
, &index
->timestamp_begin
);
1731 PERROR("ustctl_get_timestamp_begin");
1734 index
->timestamp_begin
= htobe64(index
->timestamp_begin
);
1736 ret
= ustctl_get_timestamp_end(ustream
, &index
->timestamp_end
);
1738 PERROR("ustctl_get_timestamp_end");
1741 index
->timestamp_end
= htobe64(index
->timestamp_end
);
1743 ret
= ustctl_get_events_discarded(ustream
, &index
->events_discarded
);
1745 PERROR("ustctl_get_events_discarded");
1748 index
->events_discarded
= htobe64(index
->events_discarded
);
1750 ret
= ustctl_get_content_size(ustream
, &index
->content_size
);
1752 PERROR("ustctl_get_content_size");
1755 index
->content_size
= htobe64(index
->content_size
);
1757 ret
= ustctl_get_packet_size(ustream
, &index
->packet_size
);
1759 PERROR("ustctl_get_packet_size");
1762 index
->packet_size
= htobe64(index
->packet_size
);
1764 ret
= ustctl_get_stream_id(ustream
, &index
->stream_id
);
1766 PERROR("ustctl_get_stream_id");
1769 index
->stream_id
= htobe64(index
->stream_id
);
1776 * Write up to one packet from the metadata cache to the channel.
1778 * Returns the number of bytes pushed in the cache, or a negative value
1782 int commit_one_metadata_packet(struct lttng_consumer_stream
*stream
)
1787 pthread_mutex_lock(&stream
->chan
->metadata_cache
->lock
);
1788 if (stream
->chan
->metadata_cache
->contiguous
1789 == stream
->ust_metadata_pushed
) {
1794 write_len
= ustctl_write_one_packet_to_channel(stream
->chan
->uchan
,
1795 &stream
->chan
->metadata_cache
->data
[stream
->ust_metadata_pushed
],
1796 stream
->chan
->metadata_cache
->contiguous
1797 - stream
->ust_metadata_pushed
);
1798 assert(write_len
!= 0);
1799 if (write_len
< 0) {
1800 ERR("Writing one metadata packet");
1804 stream
->ust_metadata_pushed
+= write_len
;
1806 assert(stream
->chan
->metadata_cache
->contiguous
>=
1807 stream
->ust_metadata_pushed
);
1811 pthread_mutex_unlock(&stream
->chan
->metadata_cache
->lock
);
1817 * Sync metadata meaning request them to the session daemon and snapshot to the
1818 * metadata thread can consumer them.
1820 * Metadata stream lock MUST be acquired.
1822 * Return 0 if new metadatda is available, EAGAIN if the metadata stream
1823 * is empty or a negative value on error.
1825 int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data
*ctx
,
1826 struct lttng_consumer_stream
*metadata
)
1835 * Request metadata from the sessiond, but don't wait for the flush
1836 * because we locked the metadata thread.
1838 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata
->chan
, 0, 0);
1843 ret
= commit_one_metadata_packet(metadata
);
1846 } else if (ret
> 0) {
1850 ustctl_flush_buffer(metadata
->ustream
, 1);
1851 ret
= ustctl_snapshot(metadata
->ustream
);
1853 if (errno
!= EAGAIN
) {
1854 ERR("Sync metadata, taking UST snapshot");
1857 DBG("No new metadata when syncing them.");
1858 /* No new metadata, exit. */
1864 * After this flush, we still need to extract metadata.
1875 * Return 0 on success else a negative value.
1877 static int notify_if_more_data(struct lttng_consumer_stream
*stream
,
1878 struct lttng_consumer_local_data
*ctx
)
1881 struct ustctl_consumer_stream
*ustream
;
1886 ustream
= stream
->ustream
;
1889 * First, we are going to check if there is a new subbuffer available
1890 * before reading the stream wait_fd.
1892 /* Get the next subbuffer */
1893 ret
= ustctl_get_next_subbuf(ustream
);
1895 /* No more data found, flag the stream. */
1896 stream
->has_data
= 0;
1901 ret
= ustctl_put_subbuf(ustream
);
1904 /* This stream still has data. Flag it and wake up the data thread. */
1905 stream
->has_data
= 1;
1907 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !ctx
->has_wakeup
) {
1910 writelen
= lttng_pipe_write(ctx
->consumer_wakeup_pipe
, "!", 1);
1911 if (writelen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
1916 /* The wake up pipe has been notified. */
1917 ctx
->has_wakeup
= 1;
1926 * Read subbuffer from the given stream.
1928 * Stream lock MUST be acquired.
1930 * Return 0 on success else a negative value.
1932 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
1933 struct lttng_consumer_local_data
*ctx
)
1935 unsigned long len
, subbuf_size
, padding
;
1936 int err
, write_index
= 1;
1938 struct ustctl_consumer_stream
*ustream
;
1939 struct ctf_packet_index index
;
1942 assert(stream
->ustream
);
1945 DBG("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
1948 /* Ease our life for what's next. */
1949 ustream
= stream
->ustream
;
1952 * We can consume the 1 byte written into the wait_fd by UST. Don't trigger
1953 * error if we cannot read this one byte (read returns 0), or if the error
1954 * is EAGAIN or EWOULDBLOCK.
1956 * This is only done when the stream is monitored by a thread, before the
1957 * flush is done after a hangup and if the stream is not flagged with data
1958 * since there might be nothing to consume in the wait fd but still have
1959 * data available flagged by the consumer wake up pipe.
1961 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !stream
->has_data
) {
1965 readlen
= lttng_read(stream
->wait_fd
, &dummy
, 1);
1966 if (readlen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
1973 /* Get the next subbuffer */
1974 err
= ustctl_get_next_subbuf(ustream
);
1977 * Populate metadata info if the existing info has
1978 * already been read.
1980 if (stream
->metadata_flag
) {
1981 ret
= commit_one_metadata_packet(stream
);
1985 ustctl_flush_buffer(stream
->ustream
, 1);
1989 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
1991 * This is a debug message even for single-threaded consumer,
1992 * because poll() have more relaxed criterions than get subbuf,
1993 * so get_subbuf may fail for short race windows where poll()
1994 * would issue wakeups.
1996 DBG("Reserving sub buffer failed (everything is normal, "
1997 "it is due to concurrency) [ret: %d]", err
);
2000 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
2002 if (!stream
->metadata_flag
) {
2003 index
.offset
= htobe64(stream
->out_fd_offset
);
2004 ret
= get_index_values(&index
, ustream
);
2012 /* Get the full padded subbuffer size */
2013 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
2016 /* Get subbuffer data size (without padding) */
2017 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
2020 /* Make sure we don't get a subbuffer size bigger than the padded */
2021 assert(len
>= subbuf_size
);
2023 padding
= len
- subbuf_size
;
2024 /* write the subbuffer to the tracefile */
2025 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
, &index
);
2027 * The mmap operation should write subbuf_size amount of data when network
2028 * streaming or the full padding (len) size when we are _not_ streaming.
2030 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
2031 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
2033 * Display the error but continue processing to try to release the
2034 * subbuffer. This is a DBG statement since any unexpected kill or
2035 * signal, the application gets unregistered, relayd gets closed or
2036 * anything that affects the buffer lifetime will trigger this error.
2037 * So, for the sake of the user, don't print this error since it can
2038 * happen and it is OK with the code flow.
2040 DBG("Error writing to tracefile "
2041 "(ret: %ld != len: %lu != subbuf_size: %lu)",
2042 ret
, len
, subbuf_size
);
2045 err
= ustctl_put_next_subbuf(ustream
);
2049 * This will consumer the byte on the wait_fd if and only if there is not
2050 * next subbuffer to be acquired.
2052 if (!stream
->metadata_flag
) {
2053 ret
= notify_if_more_data(stream
, ctx
);
2059 /* Write index if needed. */
2064 if (stream
->chan
->live_timer_interval
&& !stream
->metadata_flag
) {
2066 * In live, block until all the metadata is sent.
2068 err
= consumer_stream_sync_metadata(ctx
, stream
->session_id
);
2074 assert(!stream
->metadata_flag
);
2075 err
= consumer_stream_write_index(stream
, &index
);
2085 * Called when a stream is created.
2087 * Return 0 on success or else a negative value.
2089 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
2095 /* Don't create anything if this is set for streaming. */
2096 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
) {
2097 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
2098 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
2099 stream
->uid
, stream
->gid
, NULL
);
2103 stream
->out_fd
= ret
;
2104 stream
->tracefile_size_current
= 0;
2106 if (!stream
->metadata_flag
) {
2107 ret
= index_create_file(stream
->chan
->pathname
,
2108 stream
->name
, stream
->uid
, stream
->gid
,
2109 stream
->chan
->tracefile_size
,
2110 stream
->tracefile_count_current
);
2114 stream
->index_fd
= ret
;
2124 * Check if data is still being extracted from the buffers for a specific
2125 * stream. Consumer data lock MUST be acquired before calling this function
2126 * and the stream lock.
2128 * Return 1 if the traced data are still getting read else 0 meaning that the
2129 * data is available for trace viewer reading.
2131 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
2136 assert(stream
->ustream
);
2138 DBG("UST consumer checking data pending");
2140 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
2145 if (stream
->chan
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
2146 uint64_t contiguous
, pushed
;
2148 /* Ease our life a bit. */
2149 contiguous
= stream
->chan
->metadata_cache
->contiguous
;
2150 pushed
= stream
->ust_metadata_pushed
;
2153 * We can simply check whether all contiguously available data
2154 * has been pushed to the ring buffer, since the push operation
2155 * is performed within get_next_subbuf(), and because both
2156 * get_next_subbuf() and put_next_subbuf() are issued atomically
2157 * thanks to the stream lock within
2158 * lttng_ustconsumer_read_subbuffer(). This basically means that
2159 * whetnever ust_metadata_pushed is incremented, the associated
2160 * metadata has been consumed from the metadata stream.
2162 DBG("UST consumer metadata pending check: contiguous %" PRIu64
" vs pushed %" PRIu64
,
2163 contiguous
, pushed
);
2164 assert(((int64_t) (contiguous
- pushed
)) >= 0);
2165 if ((contiguous
!= pushed
) ||
2166 (((int64_t) contiguous
- pushed
) > 0 || contiguous
== 0)) {
2167 ret
= 1; /* Data is pending */
2171 ret
= ustctl_get_next_subbuf(stream
->ustream
);
2174 * There is still data so let's put back this
2177 ret
= ustctl_put_subbuf(stream
->ustream
);
2179 ret
= 1; /* Data is pending */
2184 /* Data is NOT pending so ready to be read. */
2192 * Stop a given metadata channel timer if enabled and close the wait fd which
2193 * is the poll pipe of the metadata stream.
2195 * This MUST be called with the metadata channel acquired.
2197 void lttng_ustconsumer_close_metadata(struct lttng_consumer_channel
*metadata
)
2202 assert(metadata
->type
== CONSUMER_CHANNEL_TYPE_METADATA
);
2204 DBG("Closing metadata channel key %" PRIu64
, metadata
->key
);
2206 if (metadata
->switch_timer_enabled
== 1) {
2207 consumer_timer_switch_stop(metadata
);
2210 if (!metadata
->metadata_stream
) {
2215 * Closing write side so the thread monitoring the stream wakes up if any
2216 * and clean the metadata stream.
2218 if (metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] >= 0) {
2219 ret
= close(metadata
->metadata_stream
->ust_metadata_poll_pipe
[1]);
2221 PERROR("closing metadata pipe write side");
2223 metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] = -1;
2231 * Close every metadata stream wait fd of the metadata hash table. This
2232 * function MUST be used very carefully so not to run into a race between the
2233 * metadata thread handling streams and this function closing their wait fd.
2235 * For UST, this is used when the session daemon hangs up. Its the metadata
2236 * producer so calling this is safe because we are assured that no state change
2237 * can occur in the metadata thread for the streams in the hash table.
2239 void lttng_ustconsumer_close_all_metadata(struct lttng_ht
*metadata_ht
)
2241 struct lttng_ht_iter iter
;
2242 struct lttng_consumer_stream
*stream
;
2244 assert(metadata_ht
);
2245 assert(metadata_ht
->ht
);
2247 DBG("UST consumer closing all metadata streams");
2250 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
2253 health_code_update();
2255 pthread_mutex_lock(&stream
->chan
->lock
);
2256 lttng_ustconsumer_close_metadata(stream
->chan
);
2257 pthread_mutex_unlock(&stream
->chan
->lock
);
2263 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
2267 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
2269 ERR("Unable to close wakeup fd");
2274 * Please refer to consumer-timer.c before adding any lock within this
2275 * function or any of its callees. Timers have a very strict locking
2276 * semantic with respect to teardown. Failure to respect this semantic
2277 * introduces deadlocks.
2279 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
2280 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
2282 struct lttcomm_metadata_request_msg request
;
2283 struct lttcomm_consumer_msg msg
;
2284 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
2285 uint64_t len
, key
, offset
;
2289 assert(channel
->metadata_cache
);
2291 memset(&request
, 0, sizeof(request
));
2293 /* send the metadata request to sessiond */
2294 switch (consumer_data
.type
) {
2295 case LTTNG_CONSUMER64_UST
:
2296 request
.bits_per_long
= 64;
2298 case LTTNG_CONSUMER32_UST
:
2299 request
.bits_per_long
= 32;
2302 request
.bits_per_long
= 0;
2306 request
.session_id
= channel
->session_id
;
2307 request
.session_id_per_pid
= channel
->session_id_per_pid
;
2309 * Request the application UID here so the metadata of that application can
2310 * be sent back. The channel UID corresponds to the user UID of the session
2311 * used for the rights on the stream file(s).
2313 request
.uid
= channel
->ust_app_uid
;
2314 request
.key
= channel
->key
;
2316 DBG("Sending metadata request to sessiond, session id %" PRIu64
2317 ", per-pid %" PRIu64
", app UID %u and channek key %" PRIu64
,
2318 request
.session_id
, request
.session_id_per_pid
, request
.uid
,
2321 pthread_mutex_lock(&ctx
->metadata_socket_lock
);
2323 health_code_update();
2325 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
2328 ERR("Asking metadata to sessiond");
2332 health_code_update();
2334 /* Receive the metadata from sessiond */
2335 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
2337 if (ret
!= sizeof(msg
)) {
2338 DBG("Consumer received unexpected message size %d (expects %zu)",
2340 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
2342 * The ret value might 0 meaning an orderly shutdown but this is ok
2343 * since the caller handles this.
2348 health_code_update();
2350 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
2351 /* No registry found */
2352 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2356 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
2357 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
2362 len
= msg
.u
.push_metadata
.len
;
2363 key
= msg
.u
.push_metadata
.key
;
2364 offset
= msg
.u
.push_metadata
.target_offset
;
2366 assert(key
== channel
->key
);
2368 DBG("No new metadata to receive for key %" PRIu64
, key
);
2371 health_code_update();
2373 /* Tell session daemon we are ready to receive the metadata. */
2374 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2375 LTTCOMM_CONSUMERD_SUCCESS
);
2376 if (ret
< 0 || len
== 0) {
2378 * Somehow, the session daemon is not responding anymore or there is
2379 * nothing to receive.
2384 health_code_update();
2386 ret
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
2387 key
, offset
, len
, channel
, timer
, wait
);
2390 * Only send the status msg if the sessiond is alive meaning a positive
2393 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret
);
2398 health_code_update();
2400 pthread_mutex_unlock(&ctx
->metadata_socket_lock
);
2405 * Return the ustctl call for the get stream id.
2407 int lttng_ustconsumer_get_stream_id(struct lttng_consumer_stream
*stream
,
2408 uint64_t *stream_id
)
2413 return ustctl_get_stream_id(stream
->ustream
, stream_id
);