2 * Copyright (C) 2011 Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
6 * SPDX-License-Identifier: GPL-2.0-only
17 #include <sys/socket.h>
18 #include <sys/types.h>
24 #include <bin/lttng-consumerd/health-consumerd.h>
25 #include <common/common.h>
26 #include <common/kernel-ctl/kernel-ctl.h>
27 #include <common/sessiond-comm/sessiond-comm.h>
28 #include <common/sessiond-comm/relayd.h>
29 #include <common/compat/fcntl.h>
30 #include <common/compat/endian.h>
31 #include <common/pipe.h>
32 #include <common/relayd/relayd.h>
33 #include <common/utils.h>
34 #include <common/consumer/consumer-stream.h>
35 #include <common/index/index.h>
36 #include <common/consumer/consumer-timer.h>
37 #include <common/optional.h>
38 #include <common/buffer-view.h>
39 #include <common/consumer/consumer.h>
40 #include <common/consumer/metadata-bucket.h>
42 #include "kernel-consumer.h"
44 extern struct lttng_consumer_global_data consumer_data
;
45 extern int consumer_poll_timeout
;
48 * Take a snapshot for a specific fd
50 * Returns 0 on success, < 0 on error
52 int lttng_kconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
55 int infd
= stream
->wait_fd
;
57 ret
= kernctl_snapshot(infd
);
59 * -EAGAIN is not an error, it just means that there is no data to
62 if (ret
!= 0 && ret
!= -EAGAIN
) {
63 PERROR("Getting sub-buffer snapshot.");
70 * Sample consumed and produced positions for a specific fd.
72 * Returns 0 on success, < 0 on error.
74 int lttng_kconsumer_sample_snapshot_positions(
75 struct lttng_consumer_stream
*stream
)
79 return kernctl_snapshot_sample_positions(stream
->wait_fd
);
83 * Get the produced position
85 * Returns 0 on success, < 0 on error
87 int lttng_kconsumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
91 int infd
= stream
->wait_fd
;
93 ret
= kernctl_snapshot_get_produced(infd
, pos
);
95 PERROR("kernctl_snapshot_get_produced");
102 * Get the consumerd position
104 * Returns 0 on success, < 0 on error
106 int lttng_kconsumer_get_consumed_snapshot(struct lttng_consumer_stream
*stream
,
110 int infd
= stream
->wait_fd
;
112 ret
= kernctl_snapshot_get_consumed(infd
, pos
);
114 PERROR("kernctl_snapshot_get_consumed");
121 int get_current_subbuf_addr(struct lttng_consumer_stream
*stream
,
125 unsigned long mmap_offset
;
126 const char *mmap_base
= stream
->mmap_base
;
128 ret
= kernctl_get_mmap_read_offset(stream
->wait_fd
, &mmap_offset
);
130 PERROR("Failed to get mmap read offset");
134 *addr
= mmap_base
+ mmap_offset
;
140 * Take a snapshot of all the stream of a channel
141 * RCU read-side lock must be held across this function to ensure existence of
144 * Returns 0 on success, < 0 on error
146 static int lttng_kconsumer_snapshot_channel(
147 struct lttng_consumer_channel
*channel
,
148 uint64_t key
, char *path
, uint64_t relayd_id
,
149 uint64_t nb_packets_per_stream
,
150 struct lttng_consumer_local_data
*ctx
)
153 struct lttng_consumer_stream
*stream
;
155 DBG("Kernel consumer snapshot channel %" PRIu64
, key
);
157 /* Prevent channel modifications while we perform the snapshot.*/
158 pthread_mutex_lock(&channel
->lock
);
162 /* Splice is not supported yet for channel snapshot. */
163 if (channel
->output
!= CONSUMER_CHANNEL_MMAP
) {
164 ERR("Unsupported output type for channel \"%s\": mmap output is required to record a snapshot",
170 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
171 unsigned long consumed_pos
, produced_pos
;
173 health_code_update();
176 * Lock stream because we are about to change its state.
178 pthread_mutex_lock(&stream
->lock
);
180 assert(channel
->trace_chunk
);
181 if (!lttng_trace_chunk_get(channel
->trace_chunk
)) {
183 * Can't happen barring an internal error as the channel
184 * holds a reference to the trace chunk.
186 ERR("Failed to acquire reference to channel's trace chunk");
190 assert(!stream
->trace_chunk
);
191 stream
->trace_chunk
= channel
->trace_chunk
;
194 * Assign the received relayd ID so we can use it for streaming. The streams
195 * are not visible to anyone so this is OK to change it.
197 stream
->net_seq_idx
= relayd_id
;
198 channel
->relayd_id
= relayd_id
;
199 if (relayd_id
!= (uint64_t) -1ULL) {
200 ret
= consumer_send_relayd_stream(stream
, path
);
202 ERR("sending stream to relayd");
206 ret
= consumer_stream_create_output_files(stream
,
211 DBG("Kernel consumer snapshot stream (%" PRIu64
")",
215 ret
= kernctl_buffer_flush_empty(stream
->wait_fd
);
218 * Doing a buffer flush which does not take into
219 * account empty packets. This is not perfect
220 * for stream intersection, but required as a
221 * fall-back when "flush_empty" is not
222 * implemented by lttng-modules.
224 ret
= kernctl_buffer_flush(stream
->wait_fd
);
226 ERR("Failed to flush kernel stream");
232 ret
= lttng_kconsumer_take_snapshot(stream
);
234 ERR("Taking kernel snapshot");
238 ret
= lttng_kconsumer_get_produced_snapshot(stream
, &produced_pos
);
240 ERR("Produced kernel snapshot position");
244 ret
= lttng_kconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
246 ERR("Consumerd kernel snapshot position");
250 consumed_pos
= consumer_get_consume_start_pos(consumed_pos
,
251 produced_pos
, nb_packets_per_stream
,
252 stream
->max_sb_size
);
254 while ((long) (consumed_pos
- produced_pos
) < 0) {
256 unsigned long len
, padded_len
;
257 const char *subbuf_addr
;
258 struct lttng_buffer_view subbuf_view
;
260 health_code_update();
261 DBG("Kernel consumer taking snapshot at pos %lu", consumed_pos
);
263 ret
= kernctl_get_subbuf(stream
->wait_fd
, &consumed_pos
);
265 if (ret
!= -EAGAIN
) {
266 PERROR("kernctl_get_subbuf snapshot");
269 DBG("Kernel consumer get subbuf failed. Skipping it.");
270 consumed_pos
+= stream
->max_sb_size
;
271 stream
->chan
->lost_packets
++;
275 ret
= kernctl_get_subbuf_size(stream
->wait_fd
, &len
);
277 ERR("Snapshot kernctl_get_subbuf_size");
278 goto error_put_subbuf
;
281 ret
= kernctl_get_padded_subbuf_size(stream
->wait_fd
, &padded_len
);
283 ERR("Snapshot kernctl_get_padded_subbuf_size");
284 goto error_put_subbuf
;
287 ret
= get_current_subbuf_addr(stream
, &subbuf_addr
);
289 goto error_put_subbuf
;
292 subbuf_view
= lttng_buffer_view_init(
293 subbuf_addr
, 0, padded_len
);
294 read_len
= lttng_consumer_on_read_subbuffer_mmap(
295 stream
, &subbuf_view
,
298 * We write the padded len in local tracefiles but the data len
299 * when using a relay. Display the error but continue processing
300 * to try to release the subbuffer.
302 if (relayd_id
!= (uint64_t) -1ULL) {
303 if (read_len
!= len
) {
304 ERR("Error sending to the relay (ret: %zd != len: %lu)",
308 if (read_len
!= padded_len
) {
309 ERR("Error writing to tracefile (ret: %zd != len: %lu)",
310 read_len
, padded_len
);
314 ret
= kernctl_put_subbuf(stream
->wait_fd
);
316 ERR("Snapshot kernctl_put_subbuf");
319 consumed_pos
+= stream
->max_sb_size
;
322 if (relayd_id
== (uint64_t) -1ULL) {
323 if (stream
->out_fd
>= 0) {
324 ret
= close(stream
->out_fd
);
326 PERROR("Kernel consumer snapshot close out_fd");
332 close_relayd_stream(stream
);
333 stream
->net_seq_idx
= (uint64_t) -1ULL;
335 lttng_trace_chunk_put(stream
->trace_chunk
);
336 stream
->trace_chunk
= NULL
;
337 pthread_mutex_unlock(&stream
->lock
);
345 ret
= kernctl_put_subbuf(stream
->wait_fd
);
347 ERR("Snapshot kernctl_put_subbuf error path");
350 pthread_mutex_unlock(&stream
->lock
);
353 pthread_mutex_unlock(&channel
->lock
);
358 * Read the whole metadata available for a snapshot.
359 * RCU read-side lock must be held across this function to ensure existence of
362 * Returns 0 on success, < 0 on error
364 static int lttng_kconsumer_snapshot_metadata(
365 struct lttng_consumer_channel
*metadata_channel
,
366 uint64_t key
, char *path
, uint64_t relayd_id
,
367 struct lttng_consumer_local_data
*ctx
)
369 int ret
, use_relayd
= 0;
371 struct lttng_consumer_stream
*metadata_stream
;
375 DBG("Kernel consumer snapshot metadata with key %" PRIu64
" at path %s",
380 metadata_stream
= metadata_channel
->metadata_stream
;
381 assert(metadata_stream
);
383 /* Take all the appropriate locks hehehe.*/
384 metadata_stream
->read_subbuffer_ops
.lock(metadata_stream
);
385 assert(metadata_channel
->trace_chunk
);
386 assert(metadata_stream
->trace_chunk
);
388 /* Flag once that we have a valid relayd for the stream. */
389 if (relayd_id
!= (uint64_t) -1ULL) {
394 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
399 ret
= consumer_stream_create_output_files(metadata_stream
,
407 health_code_update();
409 ret_read
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
, true);
411 ERR("Kernel snapshot reading metadata subbuffer (ret: %zd)",
416 } while (ret_read
> 0);
419 close_relayd_stream(metadata_stream
);
420 metadata_stream
->net_seq_idx
= (uint64_t) -1ULL;
422 if (metadata_stream
->out_fd
>= 0) {
423 ret
= close(metadata_stream
->out_fd
);
425 PERROR("Kernel consumer snapshot metadata close out_fd");
427 * Don't go on error here since the snapshot was successful at this
428 * point but somehow the close failed.
431 metadata_stream
->out_fd
= -1;
432 lttng_trace_chunk_put(metadata_stream
->trace_chunk
);
433 metadata_stream
->trace_chunk
= NULL
;
439 metadata_stream
->read_subbuffer_ops
.unlock(metadata_stream
);
440 cds_list_del(&metadata_stream
->send_node
);
441 consumer_stream_destroy(metadata_stream
, NULL
);
442 metadata_channel
->metadata_stream
= NULL
;
448 * Receive command from session daemon and process it.
450 * Return 1 on success else a negative value or 0.
452 int lttng_kconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
453 int sock
, struct pollfd
*consumer_sockpoll
)
456 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
457 struct lttcomm_consumer_msg msg
;
459 health_code_update();
461 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
462 if (ret
!= sizeof(msg
)) {
464 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
470 health_code_update();
472 /* Deprecated command */
473 assert(msg
.cmd_type
!= LTTNG_CONSUMER_STOP
);
475 health_code_update();
477 /* relayd needs RCU read-side protection */
480 switch (msg
.cmd_type
) {
481 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
483 /* Session daemon status message are handled in the following call. */
484 consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
485 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
486 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
,
487 msg
.u
.relayd_sock
.relayd_session_id
);
490 case LTTNG_CONSUMER_ADD_CHANNEL
:
492 struct lttng_consumer_channel
*new_channel
;
494 const uint64_t chunk_id
= msg
.u
.channel
.chunk_id
.value
;
496 health_code_update();
498 /* First send a status message before receiving the fds. */
499 ret
= consumer_send_status_msg(sock
, ret_code
);
501 /* Somehow, the session daemon is not responding anymore. */
505 health_code_update();
507 DBG("consumer_add_channel %" PRIu64
, msg
.u
.channel
.channel_key
);
508 new_channel
= consumer_allocate_channel(msg
.u
.channel
.channel_key
,
509 msg
.u
.channel
.session_id
,
510 msg
.u
.channel
.chunk_id
.is_set
?
512 msg
.u
.channel
.pathname
,
514 msg
.u
.channel
.relayd_id
, msg
.u
.channel
.output
,
515 msg
.u
.channel
.tracefile_size
,
516 msg
.u
.channel
.tracefile_count
, 0,
517 msg
.u
.channel
.monitor
,
518 msg
.u
.channel
.live_timer_interval
,
519 msg
.u
.channel
.is_live
,
521 if (new_channel
== NULL
) {
522 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
525 new_channel
->nb_init_stream_left
= msg
.u
.channel
.nb_init_streams
;
526 switch (msg
.u
.channel
.output
) {
527 case LTTNG_EVENT_SPLICE
:
528 new_channel
->output
= CONSUMER_CHANNEL_SPLICE
;
530 case LTTNG_EVENT_MMAP
:
531 new_channel
->output
= CONSUMER_CHANNEL_MMAP
;
534 ERR("Channel output unknown %d", msg
.u
.channel
.output
);
538 /* Translate and save channel type. */
539 switch (msg
.u
.channel
.type
) {
540 case CONSUMER_CHANNEL_TYPE_DATA
:
541 case CONSUMER_CHANNEL_TYPE_METADATA
:
542 new_channel
->type
= msg
.u
.channel
.type
;
549 health_code_update();
551 if (ctx
->on_recv_channel
!= NULL
) {
552 ret_recv
= ctx
->on_recv_channel(new_channel
);
554 ret
= consumer_add_channel(new_channel
, ctx
);
555 } else if (ret_recv
< 0) {
559 ret
= consumer_add_channel(new_channel
, ctx
);
561 if (msg
.u
.channel
.type
== CONSUMER_CHANNEL_TYPE_DATA
&& !ret
) {
562 int monitor_start_ret
;
564 DBG("Consumer starting monitor timer");
565 consumer_timer_live_start(new_channel
,
566 msg
.u
.channel
.live_timer_interval
);
567 monitor_start_ret
= consumer_timer_monitor_start(
569 msg
.u
.channel
.monitor_timer_interval
);
570 if (monitor_start_ret
< 0) {
571 ERR("Starting channel monitoring timer failed");
577 health_code_update();
579 /* If we received an error in add_channel, we need to report it. */
581 ret
= consumer_send_status_msg(sock
, ret
);
590 case LTTNG_CONSUMER_ADD_STREAM
:
593 struct lttng_pipe
*stream_pipe
;
594 struct lttng_consumer_stream
*new_stream
;
595 struct lttng_consumer_channel
*channel
;
599 * Get stream's channel reference. Needed when adding the stream to the
602 channel
= consumer_find_channel(msg
.u
.stream
.channel_key
);
605 * We could not find the channel. Can happen if cpu hotplug
606 * happens while tearing down.
608 ERR("Unable to find channel key %" PRIu64
, msg
.u
.stream
.channel_key
);
609 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
612 health_code_update();
614 /* First send a status message before receiving the fds. */
615 ret
= consumer_send_status_msg(sock
, ret_code
);
617 /* Somehow, the session daemon is not responding anymore. */
618 goto error_add_stream_fatal
;
621 health_code_update();
623 if (ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
624 /* Channel was not found. */
625 goto error_add_stream_nosignal
;
630 ret
= lttng_consumer_poll_socket(consumer_sockpoll
);
633 goto error_add_stream_fatal
;
636 health_code_update();
638 /* Get stream file descriptor from socket */
639 ret
= lttcomm_recv_fds_unix_sock(sock
, &fd
, 1);
640 if (ret
!= sizeof(fd
)) {
641 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_FD
);
645 health_code_update();
648 * Send status code to session daemon only if the recv works. If the
649 * above recv() failed, the session daemon is notified through the
650 * error socket and the teardown is eventually done.
652 ret
= consumer_send_status_msg(sock
, ret_code
);
654 /* Somehow, the session daemon is not responding anymore. */
655 goto error_add_stream_nosignal
;
658 health_code_update();
660 pthread_mutex_lock(&channel
->lock
);
661 new_stream
= consumer_stream_create(
668 channel
->trace_chunk
,
673 if (new_stream
== NULL
) {
678 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
681 pthread_mutex_unlock(&channel
->lock
);
682 goto error_add_stream_nosignal
;
685 new_stream
->wait_fd
= fd
;
686 ret
= kernctl_get_max_subbuf_size(new_stream
->wait_fd
,
687 &new_stream
->max_sb_size
);
689 pthread_mutex_unlock(&channel
->lock
);
690 ERR("Failed to get kernel maximal subbuffer size");
691 goto error_add_stream_nosignal
;
694 consumer_stream_update_channel_attributes(new_stream
,
698 * We've just assigned the channel to the stream so increment the
699 * refcount right now. We don't need to increment the refcount for
700 * streams in no monitor because we handle manually the cleanup of
701 * those. It is very important to make sure there is NO prior
702 * consumer_del_stream() calls or else the refcount will be unbalanced.
704 if (channel
->monitor
) {
705 uatomic_inc(&new_stream
->chan
->refcount
);
709 * The buffer flush is done on the session daemon side for the kernel
710 * so no need for the stream "hangup_flush_done" variable to be
711 * tracked. This is important for a kernel stream since we don't rely
712 * on the flush state of the stream to read data. It's not the case for
713 * user space tracing.
715 new_stream
->hangup_flush_done
= 0;
717 health_code_update();
719 pthread_mutex_lock(&new_stream
->lock
);
720 if (ctx
->on_recv_stream
) {
721 ret
= ctx
->on_recv_stream(new_stream
);
723 pthread_mutex_unlock(&new_stream
->lock
);
724 pthread_mutex_unlock(&channel
->lock
);
725 consumer_stream_free(new_stream
);
726 goto error_add_stream_nosignal
;
729 health_code_update();
731 if (new_stream
->metadata_flag
) {
732 channel
->metadata_stream
= new_stream
;
735 /* Do not monitor this stream. */
736 if (!channel
->monitor
) {
737 DBG("Kernel consumer add stream %s in no monitor mode with "
738 "relayd id %" PRIu64
, new_stream
->name
,
739 new_stream
->net_seq_idx
);
740 cds_list_add(&new_stream
->send_node
, &channel
->streams
.head
);
741 pthread_mutex_unlock(&new_stream
->lock
);
742 pthread_mutex_unlock(&channel
->lock
);
746 /* Send stream to relayd if the stream has an ID. */
747 if (new_stream
->net_seq_idx
!= (uint64_t) -1ULL) {
748 ret
= consumer_send_relayd_stream(new_stream
,
749 new_stream
->chan
->pathname
);
751 pthread_mutex_unlock(&new_stream
->lock
);
752 pthread_mutex_unlock(&channel
->lock
);
753 consumer_stream_free(new_stream
);
754 goto error_add_stream_nosignal
;
758 * If adding an extra stream to an already
759 * existing channel (e.g. cpu hotplug), we need
760 * to send the "streams_sent" command to relayd.
762 if (channel
->streams_sent_to_relayd
) {
763 ret
= consumer_send_relayd_streams_sent(
764 new_stream
->net_seq_idx
);
766 pthread_mutex_unlock(&new_stream
->lock
);
767 pthread_mutex_unlock(&channel
->lock
);
768 goto error_add_stream_nosignal
;
772 pthread_mutex_unlock(&new_stream
->lock
);
773 pthread_mutex_unlock(&channel
->lock
);
775 /* Get the right pipe where the stream will be sent. */
776 if (new_stream
->metadata_flag
) {
777 consumer_add_metadata_stream(new_stream
);
778 stream_pipe
= ctx
->consumer_metadata_pipe
;
780 consumer_add_data_stream(new_stream
);
781 stream_pipe
= ctx
->consumer_data_pipe
;
784 /* Visible to other threads */
785 new_stream
->globally_visible
= 1;
787 health_code_update();
789 ret
= lttng_pipe_write(stream_pipe
, &new_stream
, sizeof(new_stream
));
791 ERR("Consumer write %s stream to pipe %d",
792 new_stream
->metadata_flag
? "metadata" : "data",
793 lttng_pipe_get_writefd(stream_pipe
));
794 if (new_stream
->metadata_flag
) {
795 consumer_del_stream_for_metadata(new_stream
);
797 consumer_del_stream_for_data(new_stream
);
799 goto error_add_stream_nosignal
;
802 DBG("Kernel consumer ADD_STREAM %s (fd: %d) %s with relayd id %" PRIu64
,
803 new_stream
->name
, fd
, new_stream
->chan
->pathname
, new_stream
->relayd_stream_id
);
806 error_add_stream_nosignal
:
808 error_add_stream_fatal
:
811 case LTTNG_CONSUMER_STREAMS_SENT
:
813 struct lttng_consumer_channel
*channel
;
816 * Get stream's channel reference. Needed when adding the stream to the
819 channel
= consumer_find_channel(msg
.u
.sent_streams
.channel_key
);
822 * We could not find the channel. Can happen if cpu hotplug
823 * happens while tearing down.
825 ERR("Unable to find channel key %" PRIu64
,
826 msg
.u
.sent_streams
.channel_key
);
827 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
830 health_code_update();
833 * Send status code to session daemon.
835 ret
= consumer_send_status_msg(sock
, ret_code
);
836 if (ret
< 0 || ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
837 /* Somehow, the session daemon is not responding anymore. */
838 goto error_streams_sent_nosignal
;
841 health_code_update();
844 * We should not send this message if we don't monitor the
845 * streams in this channel.
847 if (!channel
->monitor
) {
848 goto end_error_streams_sent
;
851 health_code_update();
852 /* Send stream to relayd if the stream has an ID. */
853 if (msg
.u
.sent_streams
.net_seq_idx
!= (uint64_t) -1ULL) {
854 ret
= consumer_send_relayd_streams_sent(
855 msg
.u
.sent_streams
.net_seq_idx
);
857 goto error_streams_sent_nosignal
;
859 channel
->streams_sent_to_relayd
= true;
861 end_error_streams_sent
:
863 error_streams_sent_nosignal
:
866 case LTTNG_CONSUMER_UPDATE_STREAM
:
871 case LTTNG_CONSUMER_DESTROY_RELAYD
:
873 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
874 struct consumer_relayd_sock_pair
*relayd
;
876 DBG("Kernel consumer destroying relayd %" PRIu64
, index
);
878 /* Get relayd reference if exists. */
879 relayd
= consumer_find_relayd(index
);
880 if (relayd
== NULL
) {
881 DBG("Unable to find relayd %" PRIu64
, index
);
882 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
886 * Each relayd socket pair has a refcount of stream attached to it
887 * which tells if the relayd is still active or not depending on the
890 * This will set the destroy flag of the relayd object and destroy it
891 * if the refcount reaches zero when called.
893 * The destroy can happen either here or when a stream fd hangs up.
896 consumer_flag_relayd_for_destroy(relayd
);
899 health_code_update();
901 ret
= consumer_send_status_msg(sock
, ret_code
);
903 /* Somehow, the session daemon is not responding anymore. */
909 case LTTNG_CONSUMER_DATA_PENDING
:
912 uint64_t id
= msg
.u
.data_pending
.session_id
;
914 DBG("Kernel consumer data pending command for id %" PRIu64
, id
);
916 ret
= consumer_data_pending(id
);
918 health_code_update();
920 /* Send back returned value to session daemon */
921 ret
= lttcomm_send_unix_sock(sock
, &ret
, sizeof(ret
));
923 PERROR("send data pending ret code");
928 * No need to send back a status message since the data pending
929 * returned value is the response.
933 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
935 struct lttng_consumer_channel
*channel
;
936 uint64_t key
= msg
.u
.snapshot_channel
.key
;
938 channel
= consumer_find_channel(key
);
940 ERR("Channel %" PRIu64
" not found", key
);
941 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
943 if (msg
.u
.snapshot_channel
.metadata
== 1) {
944 ret
= lttng_kconsumer_snapshot_metadata(channel
, key
,
945 msg
.u
.snapshot_channel
.pathname
,
946 msg
.u
.snapshot_channel
.relayd_id
, ctx
);
948 ERR("Snapshot metadata failed");
949 ret_code
= LTTCOMM_CONSUMERD_SNAPSHOT_FAILED
;
952 ret
= lttng_kconsumer_snapshot_channel(channel
, key
,
953 msg
.u
.snapshot_channel
.pathname
,
954 msg
.u
.snapshot_channel
.relayd_id
,
955 msg
.u
.snapshot_channel
.nb_packets_per_stream
,
958 ERR("Snapshot channel failed");
959 ret_code
= LTTCOMM_CONSUMERD_SNAPSHOT_FAILED
;
963 health_code_update();
965 ret
= consumer_send_status_msg(sock
, ret_code
);
967 /* Somehow, the session daemon is not responding anymore. */
972 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
974 uint64_t key
= msg
.u
.destroy_channel
.key
;
975 struct lttng_consumer_channel
*channel
;
977 channel
= consumer_find_channel(key
);
979 ERR("Kernel consumer destroy channel %" PRIu64
" not found", key
);
980 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
983 health_code_update();
985 ret
= consumer_send_status_msg(sock
, ret_code
);
987 /* Somehow, the session daemon is not responding anymore. */
988 goto end_destroy_channel
;
991 health_code_update();
993 /* Stop right now if no channel was found. */
995 goto end_destroy_channel
;
999 * This command should ONLY be issued for channel with streams set in
1002 assert(!channel
->monitor
);
1005 * The refcount should ALWAYS be 0 in the case of a channel in no
1008 assert(!uatomic_sub_return(&channel
->refcount
, 1));
1010 consumer_del_channel(channel
);
1011 end_destroy_channel
:
1014 case LTTNG_CONSUMER_DISCARDED_EVENTS
:
1018 struct lttng_consumer_channel
*channel
;
1019 uint64_t id
= msg
.u
.discarded_events
.session_id
;
1020 uint64_t key
= msg
.u
.discarded_events
.channel_key
;
1022 DBG("Kernel consumer discarded events command for session id %"
1023 PRIu64
", channel key %" PRIu64
, id
, key
);
1025 channel
= consumer_find_channel(key
);
1027 ERR("Kernel consumer discarded events channel %"
1028 PRIu64
" not found", key
);
1031 count
= channel
->discarded_events
;
1034 health_code_update();
1036 /* Send back returned value to session daemon */
1037 ret
= lttcomm_send_unix_sock(sock
, &count
, sizeof(count
));
1039 PERROR("send discarded events");
1045 case LTTNG_CONSUMER_LOST_PACKETS
:
1049 struct lttng_consumer_channel
*channel
;
1050 uint64_t id
= msg
.u
.lost_packets
.session_id
;
1051 uint64_t key
= msg
.u
.lost_packets
.channel_key
;
1053 DBG("Kernel consumer lost packets command for session id %"
1054 PRIu64
", channel key %" PRIu64
, id
, key
);
1056 channel
= consumer_find_channel(key
);
1058 ERR("Kernel consumer lost packets channel %"
1059 PRIu64
" not found", key
);
1062 count
= channel
->lost_packets
;
1065 health_code_update();
1067 /* Send back returned value to session daemon */
1068 ret
= lttcomm_send_unix_sock(sock
, &count
, sizeof(count
));
1070 PERROR("send lost packets");
1076 case LTTNG_CONSUMER_SET_CHANNEL_MONITOR_PIPE
:
1078 int channel_monitor_pipe
;
1080 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1081 /* Successfully received the command's type. */
1082 ret
= consumer_send_status_msg(sock
, ret_code
);
1087 ret
= lttcomm_recv_fds_unix_sock(sock
, &channel_monitor_pipe
,
1089 if (ret
!= sizeof(channel_monitor_pipe
)) {
1090 ERR("Failed to receive channel monitor pipe");
1094 DBG("Received channel monitor pipe (%d)", channel_monitor_pipe
);
1095 ret
= consumer_timer_thread_set_channel_monitor_pipe(
1096 channel_monitor_pipe
);
1100 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1101 /* Set the pipe as non-blocking. */
1102 ret
= fcntl(channel_monitor_pipe
, F_GETFL
, 0);
1104 PERROR("fcntl get flags of the channel monitoring pipe");
1109 ret
= fcntl(channel_monitor_pipe
, F_SETFL
,
1110 flags
| O_NONBLOCK
);
1112 PERROR("fcntl set O_NONBLOCK flag of the channel monitoring pipe");
1115 DBG("Channel monitor pipe set as non-blocking");
1117 ret_code
= LTTCOMM_CONSUMERD_ALREADY_SET
;
1119 ret
= consumer_send_status_msg(sock
, ret_code
);
1125 case LTTNG_CONSUMER_ROTATE_CHANNEL
:
1127 struct lttng_consumer_channel
*channel
;
1128 uint64_t key
= msg
.u
.rotate_channel
.key
;
1130 DBG("Consumer rotate channel %" PRIu64
, key
);
1132 channel
= consumer_find_channel(key
);
1134 ERR("Channel %" PRIu64
" not found", key
);
1135 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1138 * Sample the rotate position of all the streams in this channel.
1140 ret
= lttng_consumer_rotate_channel(channel
, key
,
1141 msg
.u
.rotate_channel
.relayd_id
,
1142 msg
.u
.rotate_channel
.metadata
,
1145 ERR("Rotate channel failed");
1146 ret_code
= LTTCOMM_CONSUMERD_ROTATION_FAIL
;
1149 health_code_update();
1151 ret
= consumer_send_status_msg(sock
, ret_code
);
1153 /* Somehow, the session daemon is not responding anymore. */
1154 goto error_rotate_channel
;
1157 /* Rotate the streams that are ready right now. */
1158 ret
= lttng_consumer_rotate_ready_streams(
1161 ERR("Rotate ready streams failed");
1165 error_rotate_channel
:
1168 case LTTNG_CONSUMER_CLEAR_CHANNEL
:
1170 struct lttng_consumer_channel
*channel
;
1171 uint64_t key
= msg
.u
.clear_channel
.key
;
1173 channel
= consumer_find_channel(key
);
1175 DBG("Channel %" PRIu64
" not found", key
);
1176 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1178 ret
= lttng_consumer_clear_channel(channel
);
1180 ERR("Clear channel failed");
1184 health_code_update();
1186 ret
= consumer_send_status_msg(sock
, ret_code
);
1188 /* Somehow, the session daemon is not responding anymore. */
1194 case LTTNG_CONSUMER_INIT
:
1196 ret_code
= lttng_consumer_init_command(ctx
,
1197 msg
.u
.init
.sessiond_uuid
);
1198 health_code_update();
1199 ret
= consumer_send_status_msg(sock
, ret_code
);
1201 /* Somehow, the session daemon is not responding anymore. */
1206 case LTTNG_CONSUMER_CREATE_TRACE_CHUNK
:
1208 const struct lttng_credentials credentials
= {
1209 .uid
= msg
.u
.create_trace_chunk
.credentials
.value
.uid
,
1210 .gid
= msg
.u
.create_trace_chunk
.credentials
.value
.gid
,
1212 const bool is_local_trace
=
1213 !msg
.u
.create_trace_chunk
.relayd_id
.is_set
;
1214 const uint64_t relayd_id
=
1215 msg
.u
.create_trace_chunk
.relayd_id
.value
;
1216 const char *chunk_override_name
=
1217 *msg
.u
.create_trace_chunk
.override_name
?
1218 msg
.u
.create_trace_chunk
.override_name
:
1220 struct lttng_directory_handle
*chunk_directory_handle
= NULL
;
1223 * The session daemon will only provide a chunk directory file
1224 * descriptor for local traces.
1226 if (is_local_trace
) {
1229 /* Acnowledge the reception of the command. */
1230 ret
= consumer_send_status_msg(sock
,
1231 LTTCOMM_CONSUMERD_SUCCESS
);
1233 /* Somehow, the session daemon is not responding anymore. */
1237 ret
= lttcomm_recv_fds_unix_sock(sock
, &chunk_dirfd
, 1);
1238 if (ret
!= sizeof(chunk_dirfd
)) {
1239 ERR("Failed to receive trace chunk directory file descriptor");
1243 DBG("Received trace chunk directory fd (%d)",
1245 chunk_directory_handle
= lttng_directory_handle_create_from_dirfd(
1247 if (!chunk_directory_handle
) {
1248 ERR("Failed to initialize chunk directory handle from directory file descriptor");
1249 if (close(chunk_dirfd
)) {
1250 PERROR("Failed to close chunk directory file descriptor");
1256 ret_code
= lttng_consumer_create_trace_chunk(
1257 !is_local_trace
? &relayd_id
: NULL
,
1258 msg
.u
.create_trace_chunk
.session_id
,
1259 msg
.u
.create_trace_chunk
.chunk_id
,
1260 (time_t) msg
.u
.create_trace_chunk
1261 .creation_timestamp
,
1262 chunk_override_name
,
1263 msg
.u
.create_trace_chunk
.credentials
.is_set
?
1266 chunk_directory_handle
);
1267 lttng_directory_handle_put(chunk_directory_handle
);
1268 goto end_msg_sessiond
;
1270 case LTTNG_CONSUMER_CLOSE_TRACE_CHUNK
:
1272 enum lttng_trace_chunk_command_type close_command
=
1273 msg
.u
.close_trace_chunk
.close_command
.value
;
1274 const uint64_t relayd_id
=
1275 msg
.u
.close_trace_chunk
.relayd_id
.value
;
1276 struct lttcomm_consumer_close_trace_chunk_reply reply
;
1277 char path
[LTTNG_PATH_MAX
];
1279 ret_code
= lttng_consumer_close_trace_chunk(
1280 msg
.u
.close_trace_chunk
.relayd_id
.is_set
?
1283 msg
.u
.close_trace_chunk
.session_id
,
1284 msg
.u
.close_trace_chunk
.chunk_id
,
1285 (time_t) msg
.u
.close_trace_chunk
.close_timestamp
,
1286 msg
.u
.close_trace_chunk
.close_command
.is_set
?
1289 reply
.ret_code
= ret_code
;
1290 reply
.path_length
= strlen(path
) + 1;
1291 ret
= lttcomm_send_unix_sock(sock
, &reply
, sizeof(reply
));
1292 if (ret
!= sizeof(reply
)) {
1295 ret
= lttcomm_send_unix_sock(sock
, path
, reply
.path_length
);
1296 if (ret
!= reply
.path_length
) {
1301 case LTTNG_CONSUMER_TRACE_CHUNK_EXISTS
:
1303 const uint64_t relayd_id
=
1304 msg
.u
.trace_chunk_exists
.relayd_id
.value
;
1306 ret_code
= lttng_consumer_trace_chunk_exists(
1307 msg
.u
.trace_chunk_exists
.relayd_id
.is_set
?
1309 msg
.u
.trace_chunk_exists
.session_id
,
1310 msg
.u
.trace_chunk_exists
.chunk_id
);
1311 goto end_msg_sessiond
;
1313 case LTTNG_CONSUMER_OPEN_CHANNEL_PACKETS
:
1315 const uint64_t key
= msg
.u
.open_channel_packets
.key
;
1316 struct lttng_consumer_channel
*channel
=
1317 consumer_find_channel(key
);
1320 pthread_mutex_lock(&channel
->lock
);
1321 ret_code
= lttng_consumer_open_channel_packets(channel
);
1322 pthread_mutex_unlock(&channel
->lock
);
1324 WARN("Channel %" PRIu64
" not found", key
);
1325 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1328 health_code_update();
1329 goto end_msg_sessiond
;
1337 * Return 1 to indicate success since the 0 value can be a socket
1338 * shutdown during the recv() or send() call.
1343 /* This will issue a consumer stop. */
1348 * The returned value here is not useful since either way we'll return 1 to
1349 * the caller because the session daemon socket management is done
1350 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1352 ret
= consumer_send_status_msg(sock
, ret_code
);
1358 health_code_update();
1364 * Sync metadata meaning request them to the session daemon and snapshot to the
1365 * metadata thread can consumer them.
1367 * Metadata stream lock MUST be acquired.
1369 enum sync_metadata_status
lttng_kconsumer_sync_metadata(
1370 struct lttng_consumer_stream
*metadata
)
1373 enum sync_metadata_status status
;
1377 ret
= kernctl_buffer_flush(metadata
->wait_fd
);
1379 ERR("Failed to flush kernel stream");
1380 status
= SYNC_METADATA_STATUS_ERROR
;
1384 ret
= kernctl_snapshot(metadata
->wait_fd
);
1386 if (errno
== EAGAIN
) {
1387 /* No new metadata, exit. */
1388 DBG("Sync metadata, no new kernel metadata");
1389 status
= SYNC_METADATA_STATUS_NO_DATA
;
1391 ERR("Sync metadata, taking kernel snapshot failed.");
1392 status
= SYNC_METADATA_STATUS_ERROR
;
1395 status
= SYNC_METADATA_STATUS_NEW_DATA
;
1403 int extract_common_subbuffer_info(struct lttng_consumer_stream
*stream
,
1404 struct stream_subbuffer
*subbuf
)
1408 ret
= kernctl_get_subbuf_size(
1409 stream
->wait_fd
, &subbuf
->info
.data
.subbuf_size
);
1414 ret
= kernctl_get_padded_subbuf_size(
1415 stream
->wait_fd
, &subbuf
->info
.data
.padded_subbuf_size
);
1425 int extract_metadata_subbuffer_info(struct lttng_consumer_stream
*stream
,
1426 struct stream_subbuffer
*subbuf
)
1430 ret
= extract_common_subbuffer_info(stream
, subbuf
);
1435 ret
= kernctl_get_metadata_version(
1436 stream
->wait_fd
, &subbuf
->info
.metadata
.version
);
1446 int extract_data_subbuffer_info(struct lttng_consumer_stream
*stream
,
1447 struct stream_subbuffer
*subbuf
)
1451 ret
= extract_common_subbuffer_info(stream
, subbuf
);
1456 ret
= kernctl_get_packet_size(
1457 stream
->wait_fd
, &subbuf
->info
.data
.packet_size
);
1459 PERROR("Failed to get sub-buffer packet size");
1463 ret
= kernctl_get_content_size(
1464 stream
->wait_fd
, &subbuf
->info
.data
.content_size
);
1466 PERROR("Failed to get sub-buffer content size");
1470 ret
= kernctl_get_timestamp_begin(
1471 stream
->wait_fd
, &subbuf
->info
.data
.timestamp_begin
);
1473 PERROR("Failed to get sub-buffer begin timestamp");
1477 ret
= kernctl_get_timestamp_end(
1478 stream
->wait_fd
, &subbuf
->info
.data
.timestamp_end
);
1480 PERROR("Failed to get sub-buffer end timestamp");
1484 ret
= kernctl_get_events_discarded(
1485 stream
->wait_fd
, &subbuf
->info
.data
.events_discarded
);
1487 PERROR("Failed to get sub-buffer events discarded count");
1491 ret
= kernctl_get_sequence_number(stream
->wait_fd
,
1492 &subbuf
->info
.data
.sequence_number
.value
);
1494 /* May not be supported by older LTTng-modules. */
1495 if (ret
!= -ENOTTY
) {
1496 PERROR("Failed to get sub-buffer sequence number");
1500 subbuf
->info
.data
.sequence_number
.is_set
= true;
1503 ret
= kernctl_get_stream_id(
1504 stream
->wait_fd
, &subbuf
->info
.data
.stream_id
);
1506 PERROR("Failed to get stream id");
1510 ret
= kernctl_get_instance_id(stream
->wait_fd
,
1511 &subbuf
->info
.data
.stream_instance_id
.value
);
1513 /* May not be supported by older LTTng-modules. */
1514 if (ret
!= -ENOTTY
) {
1515 PERROR("Failed to get stream instance id");
1519 subbuf
->info
.data
.stream_instance_id
.is_set
= true;
1526 int get_subbuffer_common(struct lttng_consumer_stream
*stream
,
1527 struct stream_subbuffer
*subbuffer
)
1531 ret
= kernctl_get_next_subbuf(stream
->wait_fd
);
1534 * The caller only expects -ENODATA when there is no data to
1535 * read, but the kernel tracer returns -EAGAIN when there is
1536 * currently no data for a non-finalized stream, and -ENODATA
1537 * when there is no data for a finalized stream. Those can be
1538 * combined into a -ENODATA return value.
1540 if (ret
== -EAGAIN
) {
1547 ret
= stream
->read_subbuffer_ops
.extract_subbuffer_info(
1554 int get_next_subbuffer_splice(struct lttng_consumer_stream
*stream
,
1555 struct stream_subbuffer
*subbuffer
)
1559 ret
= get_subbuffer_common(stream
, subbuffer
);
1564 subbuffer
->buffer
.fd
= stream
->wait_fd
;
1570 int get_next_subbuffer_mmap(struct lttng_consumer_stream
*stream
,
1571 struct stream_subbuffer
*subbuffer
)
1576 ret
= get_subbuffer_common(stream
, subbuffer
);
1581 ret
= get_current_subbuf_addr(stream
, &addr
);
1586 subbuffer
->buffer
.buffer
= lttng_buffer_view_init(
1587 addr
, 0, subbuffer
->info
.data
.padded_subbuf_size
);
1593 int get_next_subbuffer_metadata_check(struct lttng_consumer_stream
*stream
,
1594 struct stream_subbuffer
*subbuffer
)
1600 ret
= kernctl_get_next_subbuf_metadata_check(stream
->wait_fd
,
1606 ret
= stream
->read_subbuffer_ops
.extract_subbuffer_info(
1612 LTTNG_OPTIONAL_SET(&subbuffer
->info
.metadata
.coherent
, coherent
);
1614 ret
= get_current_subbuf_addr(stream
, &addr
);
1619 subbuffer
->buffer
.buffer
= lttng_buffer_view_init(
1620 addr
, 0, subbuffer
->info
.data
.padded_subbuf_size
);
1621 DBG("Got metadata packet with padded_subbuf_size = %lu, coherent = %s",
1622 subbuffer
->info
.metadata
.padded_subbuf_size
,
1623 coherent
? "true" : "false");
1626 * The caller only expects -ENODATA when there is no data to read, but
1627 * the kernel tracer returns -EAGAIN when there is currently no data
1628 * for a non-finalized stream, and -ENODATA when there is no data for a
1629 * finalized stream. Those can be combined into a -ENODATA return value.
1631 if (ret
== -EAGAIN
) {
1639 int put_next_subbuffer(struct lttng_consumer_stream
*stream
,
1640 struct stream_subbuffer
*subbuffer
)
1642 const int ret
= kernctl_put_next_subbuf(stream
->wait_fd
);
1645 if (ret
== -EFAULT
) {
1646 PERROR("Error in unreserving sub buffer");
1647 } else if (ret
== -EIO
) {
1648 /* Should never happen with newer LTTng versions */
1649 PERROR("Reader has been pushed by the writer, last sub-buffer corrupted");
1657 bool is_get_next_check_metadata_available(int tracer_fd
)
1659 const int ret
= kernctl_get_next_subbuf_metadata_check(tracer_fd
, NULL
);
1660 const bool available
= ret
!= -ENOTTY
;
1663 /* get succeeded, make sure to put the subbuffer. */
1664 kernctl_put_subbuf(tracer_fd
);
1671 int signal_metadata(struct lttng_consumer_stream
*stream
,
1672 struct lttng_consumer_local_data
*ctx
)
1674 ASSERT_LOCKED(stream
->metadata_rdv_lock
);
1675 return pthread_cond_broadcast(&stream
->metadata_rdv
) ? -errno
: 0;
1679 int lttng_kconsumer_set_stream_ops(
1680 struct lttng_consumer_stream
*stream
)
1684 if (stream
->metadata_flag
&& stream
->chan
->is_live
) {
1685 DBG("Attempting to enable metadata bucketization for live consumers");
1686 if (is_get_next_check_metadata_available(stream
->wait_fd
)) {
1687 DBG("Kernel tracer supports get_next_subbuffer_metadata_check, metadata will be accumulated until a coherent state is reached");
1688 stream
->read_subbuffer_ops
.get_next_subbuffer
=
1689 get_next_subbuffer_metadata_check
;
1690 ret
= consumer_stream_enable_metadata_bucketization(
1697 * The kernel tracer version is too old to indicate
1698 * when the metadata stream has reached a "coherent"
1699 * (parseable) point.
1701 * This means that a live viewer may see an incoherent
1702 * sequence of metadata and fail to parse it.
1704 WARN("Kernel tracer does not support get_next_subbuffer_metadata_check which may cause live clients to fail to parse the metadata stream");
1705 metadata_bucket_destroy(stream
->metadata_bucket
);
1706 stream
->metadata_bucket
= NULL
;
1709 stream
->read_subbuffer_ops
.on_sleep
= signal_metadata
;
1712 if (!stream
->read_subbuffer_ops
.get_next_subbuffer
) {
1713 if (stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
) {
1714 stream
->read_subbuffer_ops
.get_next_subbuffer
=
1715 get_next_subbuffer_mmap
;
1717 stream
->read_subbuffer_ops
.get_next_subbuffer
=
1718 get_next_subbuffer_splice
;
1722 if (stream
->metadata_flag
) {
1723 stream
->read_subbuffer_ops
.extract_subbuffer_info
=
1724 extract_metadata_subbuffer_info
;
1726 stream
->read_subbuffer_ops
.extract_subbuffer_info
=
1727 extract_data_subbuffer_info
;
1728 if (stream
->chan
->is_live
) {
1729 stream
->read_subbuffer_ops
.send_live_beacon
=
1730 consumer_flush_kernel_index
;
1734 stream
->read_subbuffer_ops
.put_next_subbuffer
= put_next_subbuffer
;
1739 int lttng_kconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
1746 * Don't create anything if this is set for streaming or if there is
1747 * no current trace chunk on the parent channel.
1749 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
&&
1750 stream
->chan
->trace_chunk
) {
1751 ret
= consumer_stream_create_output_files(stream
, true);
1757 if (stream
->output
== LTTNG_EVENT_MMAP
) {
1758 /* get the len of the mmap region */
1759 unsigned long mmap_len
;
1761 ret
= kernctl_get_mmap_len(stream
->wait_fd
, &mmap_len
);
1763 PERROR("kernctl_get_mmap_len");
1764 goto error_close_fd
;
1766 stream
->mmap_len
= (size_t) mmap_len
;
1768 stream
->mmap_base
= mmap(NULL
, stream
->mmap_len
, PROT_READ
,
1769 MAP_PRIVATE
, stream
->wait_fd
, 0);
1770 if (stream
->mmap_base
== MAP_FAILED
) {
1771 PERROR("Error mmaping");
1773 goto error_close_fd
;
1777 ret
= lttng_kconsumer_set_stream_ops(stream
);
1779 goto error_close_fd
;
1782 /* we return 0 to let the library handle the FD internally */
1786 if (stream
->out_fd
>= 0) {
1789 err
= close(stream
->out_fd
);
1791 stream
->out_fd
= -1;
1798 * Check if data is still being extracted from the buffers for a specific
1799 * stream. Consumer data lock MUST be acquired before calling this function
1800 * and the stream lock.
1802 * Return 1 if the traced data are still getting read else 0 meaning that the
1803 * data is available for trace viewer reading.
1805 int lttng_kconsumer_data_pending(struct lttng_consumer_stream
*stream
)
1811 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
1816 ret
= kernctl_get_next_subbuf(stream
->wait_fd
);
1818 /* There is still data so let's put back this subbuffer. */
1819 ret
= kernctl_put_subbuf(stream
->wait_fd
);
1821 ret
= 1; /* Data is pending */
1825 /* Data is NOT pending and ready to be read. */