2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * 2012 - David Goulet <dgoulet@efficios.com>
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License, version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
27 #include <sys/socket.h>
28 #include <sys/types.h>
33 #include <common/common.h>
34 #include <common/utils.h>
35 #include <common/compat/poll.h>
36 #include <common/index/index.h>
37 #include <common/kernel-ctl/kernel-ctl.h>
38 #include <common/sessiond-comm/relayd.h>
39 #include <common/sessiond-comm/sessiond-comm.h>
40 #include <common/kernel-consumer/kernel-consumer.h>
41 #include <common/relayd/relayd.h>
42 #include <common/ust-consumer/ust-consumer.h>
43 #include <common/consumer-timer.h>
46 #include "consumer-stream.h"
48 struct lttng_consumer_global_data consumer_data
= {
51 .type
= LTTNG_CONSUMER_UNKNOWN
,
54 enum consumer_channel_action
{
57 CONSUMER_CHANNEL_QUIT
,
60 struct consumer_channel_msg
{
61 enum consumer_channel_action action
;
62 struct lttng_consumer_channel
*chan
; /* add */
63 uint64_t key
; /* del */
67 * Flag to inform the polling thread to quit when all fd hung up. Updated by
68 * the consumer_thread_receive_fds when it notices that all fds has hung up.
69 * Also updated by the signal handler (consumer_should_exit()). Read by the
72 volatile int consumer_quit
;
75 * Global hash table containing respectively metadata and data streams. The
76 * stream element in this ht should only be updated by the metadata poll thread
77 * for the metadata and the data poll thread for the data.
79 static struct lttng_ht
*metadata_ht
;
80 static struct lttng_ht
*data_ht
;
83 * Notify a thread lttng pipe to poll back again. This usually means that some
84 * global state has changed so we just send back the thread in a poll wait
87 static void notify_thread_lttng_pipe(struct lttng_pipe
*pipe
)
89 struct lttng_consumer_stream
*null_stream
= NULL
;
93 (void) lttng_pipe_write(pipe
, &null_stream
, sizeof(null_stream
));
96 static void notify_channel_pipe(struct lttng_consumer_local_data
*ctx
,
97 struct lttng_consumer_channel
*chan
,
99 enum consumer_channel_action action
)
101 struct consumer_channel_msg msg
;
104 memset(&msg
, 0, sizeof(msg
));
110 ret
= write(ctx
->consumer_channel_pipe
[1], &msg
, sizeof(msg
));
111 } while (ret
< 0 && errno
== EINTR
);
114 void notify_thread_del_channel(struct lttng_consumer_local_data
*ctx
,
117 notify_channel_pipe(ctx
, NULL
, key
, CONSUMER_CHANNEL_DEL
);
120 static int read_channel_pipe(struct lttng_consumer_local_data
*ctx
,
121 struct lttng_consumer_channel
**chan
,
123 enum consumer_channel_action
*action
)
125 struct consumer_channel_msg msg
;
129 ret
= read(ctx
->consumer_channel_pipe
[0], &msg
, sizeof(msg
));
130 } while (ret
< 0 && errno
== EINTR
);
132 *action
= msg
.action
;
140 * Find a stream. The consumer_data.lock must be locked during this
143 static struct lttng_consumer_stream
*find_stream(uint64_t key
,
146 struct lttng_ht_iter iter
;
147 struct lttng_ht_node_u64
*node
;
148 struct lttng_consumer_stream
*stream
= NULL
;
152 /* -1ULL keys are lookup failures */
153 if (key
== (uint64_t) -1ULL) {
159 lttng_ht_lookup(ht
, &key
, &iter
);
160 node
= lttng_ht_iter_get_node_u64(&iter
);
162 stream
= caa_container_of(node
, struct lttng_consumer_stream
, node
);
170 static void steal_stream_key(uint64_t key
, struct lttng_ht
*ht
)
172 struct lttng_consumer_stream
*stream
;
175 stream
= find_stream(key
, ht
);
177 stream
->key
= (uint64_t) -1ULL;
179 * We don't want the lookup to match, but we still need
180 * to iterate on this stream when iterating over the hash table. Just
181 * change the node key.
183 stream
->node
.key
= (uint64_t) -1ULL;
189 * Return a channel object for the given key.
191 * RCU read side lock MUST be acquired before calling this function and
192 * protects the channel ptr.
194 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
)
196 struct lttng_ht_iter iter
;
197 struct lttng_ht_node_u64
*node
;
198 struct lttng_consumer_channel
*channel
= NULL
;
200 /* -1ULL keys are lookup failures */
201 if (key
== (uint64_t) -1ULL) {
205 lttng_ht_lookup(consumer_data
.channel_ht
, &key
, &iter
);
206 node
= lttng_ht_iter_get_node_u64(&iter
);
208 channel
= caa_container_of(node
, struct lttng_consumer_channel
, node
);
214 static void free_stream_rcu(struct rcu_head
*head
)
216 struct lttng_ht_node_u64
*node
=
217 caa_container_of(head
, struct lttng_ht_node_u64
, head
);
218 struct lttng_consumer_stream
*stream
=
219 caa_container_of(node
, struct lttng_consumer_stream
, node
);
224 static void free_channel_rcu(struct rcu_head
*head
)
226 struct lttng_ht_node_u64
*node
=
227 caa_container_of(head
, struct lttng_ht_node_u64
, head
);
228 struct lttng_consumer_channel
*channel
=
229 caa_container_of(node
, struct lttng_consumer_channel
, node
);
235 * RCU protected relayd socket pair free.
237 static void free_relayd_rcu(struct rcu_head
*head
)
239 struct lttng_ht_node_u64
*node
=
240 caa_container_of(head
, struct lttng_ht_node_u64
, head
);
241 struct consumer_relayd_sock_pair
*relayd
=
242 caa_container_of(node
, struct consumer_relayd_sock_pair
, node
);
245 * Close all sockets. This is done in the call RCU since we don't want the
246 * socket fds to be reassigned thus potentially creating bad state of the
249 * We do not have to lock the control socket mutex here since at this stage
250 * there is no one referencing to this relayd object.
252 (void) relayd_close(&relayd
->control_sock
);
253 (void) relayd_close(&relayd
->data_sock
);
259 * Destroy and free relayd socket pair object.
261 void consumer_destroy_relayd(struct consumer_relayd_sock_pair
*relayd
)
264 struct lttng_ht_iter iter
;
266 if (relayd
== NULL
) {
270 DBG("Consumer destroy and close relayd socket pair");
272 iter
.iter
.node
= &relayd
->node
.node
;
273 ret
= lttng_ht_del(consumer_data
.relayd_ht
, &iter
);
275 /* We assume the relayd is being or is destroyed */
279 /* RCU free() call */
280 call_rcu(&relayd
->node
.head
, free_relayd_rcu
);
284 * Remove a channel from the global list protected by a mutex. This function is
285 * also responsible for freeing its data structures.
287 void consumer_del_channel(struct lttng_consumer_channel
*channel
)
290 struct lttng_ht_iter iter
;
291 struct lttng_consumer_stream
*stream
, *stmp
;
293 DBG("Consumer delete channel key %" PRIu64
, channel
->key
);
295 pthread_mutex_lock(&consumer_data
.lock
);
296 pthread_mutex_lock(&channel
->lock
);
298 /* Delete streams that might have been left in the stream list. */
299 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
301 cds_list_del(&stream
->send_node
);
303 * Once a stream is added to this list, the buffers were created so
304 * we have a guarantee that this call will succeed.
306 consumer_stream_destroy(stream
, NULL
);
309 if (channel
->live_timer_enabled
== 1) {
310 consumer_timer_live_stop(channel
);
313 switch (consumer_data
.type
) {
314 case LTTNG_CONSUMER_KERNEL
:
316 case LTTNG_CONSUMER32_UST
:
317 case LTTNG_CONSUMER64_UST
:
318 lttng_ustconsumer_del_channel(channel
);
321 ERR("Unknown consumer_data type");
327 iter
.iter
.node
= &channel
->node
.node
;
328 ret
= lttng_ht_del(consumer_data
.channel_ht
, &iter
);
332 call_rcu(&channel
->node
.head
, free_channel_rcu
);
334 pthread_mutex_unlock(&channel
->lock
);
335 pthread_mutex_unlock(&consumer_data
.lock
);
339 * Iterate over the relayd hash table and destroy each element. Finally,
340 * destroy the whole hash table.
342 static void cleanup_relayd_ht(void)
344 struct lttng_ht_iter iter
;
345 struct consumer_relayd_sock_pair
*relayd
;
349 cds_lfht_for_each_entry(consumer_data
.relayd_ht
->ht
, &iter
.iter
, relayd
,
351 consumer_destroy_relayd(relayd
);
356 lttng_ht_destroy(consumer_data
.relayd_ht
);
360 * Update the end point status of all streams having the given network sequence
361 * index (relayd index).
363 * It's atomically set without having the stream mutex locked which is fine
364 * because we handle the write/read race with a pipe wakeup for each thread.
366 static void update_endpoint_status_by_netidx(uint64_t net_seq_idx
,
367 enum consumer_endpoint_status status
)
369 struct lttng_ht_iter iter
;
370 struct lttng_consumer_stream
*stream
;
372 DBG("Consumer set delete flag on stream by idx %" PRIu64
, net_seq_idx
);
376 /* Let's begin with metadata */
377 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
, node
.node
) {
378 if (stream
->net_seq_idx
== net_seq_idx
) {
379 uatomic_set(&stream
->endpoint_status
, status
);
380 DBG("Delete flag set to metadata stream %d", stream
->wait_fd
);
384 /* Follow up by the data streams */
385 cds_lfht_for_each_entry(data_ht
->ht
, &iter
.iter
, stream
, node
.node
) {
386 if (stream
->net_seq_idx
== net_seq_idx
) {
387 uatomic_set(&stream
->endpoint_status
, status
);
388 DBG("Delete flag set to data stream %d", stream
->wait_fd
);
395 * Cleanup a relayd object by flagging every associated streams for deletion,
396 * destroying the object meaning removing it from the relayd hash table,
397 * closing the sockets and freeing the memory in a RCU call.
399 * If a local data context is available, notify the threads that the streams'
400 * state have changed.
402 static void cleanup_relayd(struct consumer_relayd_sock_pair
*relayd
,
403 struct lttng_consumer_local_data
*ctx
)
409 DBG("Cleaning up relayd sockets");
411 /* Save the net sequence index before destroying the object */
412 netidx
= relayd
->net_seq_idx
;
415 * Delete the relayd from the relayd hash table, close the sockets and free
416 * the object in a RCU call.
418 consumer_destroy_relayd(relayd
);
420 /* Set inactive endpoint to all streams */
421 update_endpoint_status_by_netidx(netidx
, CONSUMER_ENDPOINT_INACTIVE
);
424 * With a local data context, notify the threads that the streams' state
425 * have changed. The write() action on the pipe acts as an "implicit"
426 * memory barrier ordering the updates of the end point status from the
427 * read of this status which happens AFTER receiving this notify.
430 notify_thread_lttng_pipe(ctx
->consumer_data_pipe
);
431 notify_thread_lttng_pipe(ctx
->consumer_metadata_pipe
);
436 * Flag a relayd socket pair for destruction. Destroy it if the refcount
439 * RCU read side lock MUST be aquired before calling this function.
441 void consumer_flag_relayd_for_destroy(struct consumer_relayd_sock_pair
*relayd
)
445 /* Set destroy flag for this object */
446 uatomic_set(&relayd
->destroy_flag
, 1);
448 /* Destroy the relayd if refcount is 0 */
449 if (uatomic_read(&relayd
->refcount
) == 0) {
450 consumer_destroy_relayd(relayd
);
455 * Completly destroy stream from every visiable data structure and the given
458 * One this call returns, the stream object is not longer usable nor visible.
460 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
463 consumer_stream_destroy(stream
, ht
);
467 * XXX naming of del vs destroy is all mixed up.
469 void consumer_del_stream_for_data(struct lttng_consumer_stream
*stream
)
471 consumer_stream_destroy(stream
, data_ht
);
474 void consumer_del_stream_for_metadata(struct lttng_consumer_stream
*stream
)
476 consumer_stream_destroy(stream
, metadata_ht
);
479 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
481 enum lttng_consumer_stream_state state
,
482 const char *channel_name
,
489 enum consumer_channel_type type
,
490 unsigned int monitor
)
493 struct lttng_consumer_stream
*stream
;
495 stream
= zmalloc(sizeof(*stream
));
496 if (stream
== NULL
) {
497 PERROR("malloc struct lttng_consumer_stream");
504 stream
->key
= stream_key
;
506 stream
->out_fd_offset
= 0;
507 stream
->output_written
= 0;
508 stream
->state
= state
;
511 stream
->net_seq_idx
= relayd_id
;
512 stream
->session_id
= session_id
;
513 stream
->monitor
= monitor
;
514 stream
->endpoint_status
= CONSUMER_ENDPOINT_ACTIVE
;
515 stream
->index_fd
= -1;
516 pthread_mutex_init(&stream
->lock
, NULL
);
518 /* If channel is the metadata, flag this stream as metadata. */
519 if (type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
520 stream
->metadata_flag
= 1;
521 /* Metadata is flat out. */
522 strncpy(stream
->name
, DEFAULT_METADATA_NAME
, sizeof(stream
->name
));
523 /* Live rendez-vous point. */
524 pthread_cond_init(&stream
->metadata_rdv
, NULL
);
525 pthread_mutex_init(&stream
->metadata_rdv_lock
, NULL
);
527 /* Format stream name to <channel_name>_<cpu_number> */
528 ret
= snprintf(stream
->name
, sizeof(stream
->name
), "%s_%d",
531 PERROR("snprintf stream name");
536 /* Key is always the wait_fd for streams. */
537 lttng_ht_node_init_u64(&stream
->node
, stream
->key
);
539 /* Init node per channel id key */
540 lttng_ht_node_init_u64(&stream
->node_channel_id
, channel_key
);
542 /* Init session id node with the stream session id */
543 lttng_ht_node_init_u64(&stream
->node_session_id
, stream
->session_id
);
545 DBG3("Allocated stream %s (key %" PRIu64
", chan_key %" PRIu64
546 " relayd_id %" PRIu64
", session_id %" PRIu64
,
547 stream
->name
, stream
->key
, channel_key
,
548 stream
->net_seq_idx
, stream
->session_id
);
564 * Add a stream to the global list protected by a mutex.
566 int consumer_add_data_stream(struct lttng_consumer_stream
*stream
)
568 struct lttng_ht
*ht
= data_ht
;
574 DBG3("Adding consumer stream %" PRIu64
, stream
->key
);
576 pthread_mutex_lock(&consumer_data
.lock
);
577 pthread_mutex_lock(&stream
->chan
->lock
);
578 pthread_mutex_lock(&stream
->chan
->timer_lock
);
579 pthread_mutex_lock(&stream
->lock
);
582 /* Steal stream identifier to avoid having streams with the same key */
583 steal_stream_key(stream
->key
, ht
);
585 lttng_ht_add_unique_u64(ht
, &stream
->node
);
587 lttng_ht_add_u64(consumer_data
.stream_per_chan_id_ht
,
588 &stream
->node_channel_id
);
591 * Add stream to the stream_list_ht of the consumer data. No need to steal
592 * the key since the HT does not use it and we allow to add redundant keys
595 lttng_ht_add_u64(consumer_data
.stream_list_ht
, &stream
->node_session_id
);
598 * When nb_init_stream_left reaches 0, we don't need to trigger any action
599 * in terms of destroying the associated channel, because the action that
600 * causes the count to become 0 also causes a stream to be added. The
601 * channel deletion will thus be triggered by the following removal of this
604 if (uatomic_read(&stream
->chan
->nb_init_stream_left
) > 0) {
605 /* Increment refcount before decrementing nb_init_stream_left */
607 uatomic_dec(&stream
->chan
->nb_init_stream_left
);
610 /* Update consumer data once the node is inserted. */
611 consumer_data
.stream_count
++;
612 consumer_data
.need_update
= 1;
615 pthread_mutex_unlock(&stream
->lock
);
616 pthread_mutex_unlock(&stream
->chan
->timer_lock
);
617 pthread_mutex_unlock(&stream
->chan
->lock
);
618 pthread_mutex_unlock(&consumer_data
.lock
);
623 void consumer_del_data_stream(struct lttng_consumer_stream
*stream
)
625 consumer_del_stream(stream
, data_ht
);
629 * Add relayd socket to global consumer data hashtable. RCU read side lock MUST
630 * be acquired before calling this.
632 static int add_relayd(struct consumer_relayd_sock_pair
*relayd
)
635 struct lttng_ht_node_u64
*node
;
636 struct lttng_ht_iter iter
;
640 lttng_ht_lookup(consumer_data
.relayd_ht
,
641 &relayd
->net_seq_idx
, &iter
);
642 node
= lttng_ht_iter_get_node_u64(&iter
);
646 lttng_ht_add_unique_u64(consumer_data
.relayd_ht
, &relayd
->node
);
653 * Allocate and return a consumer relayd socket.
655 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
656 uint64_t net_seq_idx
)
658 struct consumer_relayd_sock_pair
*obj
= NULL
;
660 /* net sequence index of -1 is a failure */
661 if (net_seq_idx
== (uint64_t) -1ULL) {
665 obj
= zmalloc(sizeof(struct consumer_relayd_sock_pair
));
667 PERROR("zmalloc relayd sock");
671 obj
->net_seq_idx
= net_seq_idx
;
673 obj
->destroy_flag
= 0;
674 obj
->control_sock
.sock
.fd
= -1;
675 obj
->data_sock
.sock
.fd
= -1;
676 lttng_ht_node_init_u64(&obj
->node
, obj
->net_seq_idx
);
677 pthread_mutex_init(&obj
->ctrl_sock_mutex
, NULL
);
684 * Find a relayd socket pair in the global consumer data.
686 * Return the object if found else NULL.
687 * RCU read-side lock must be held across this call and while using the
690 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
)
692 struct lttng_ht_iter iter
;
693 struct lttng_ht_node_u64
*node
;
694 struct consumer_relayd_sock_pair
*relayd
= NULL
;
696 /* Negative keys are lookup failures */
697 if (key
== (uint64_t) -1ULL) {
701 lttng_ht_lookup(consumer_data
.relayd_ht
, &key
,
703 node
= lttng_ht_iter_get_node_u64(&iter
);
705 relayd
= caa_container_of(node
, struct consumer_relayd_sock_pair
, node
);
713 * Find a relayd and send the stream
715 * Returns 0 on success, < 0 on error
717 int consumer_send_relayd_stream(struct lttng_consumer_stream
*stream
,
721 struct consumer_relayd_sock_pair
*relayd
;
724 assert(stream
->net_seq_idx
!= -1ULL);
727 /* The stream is not metadata. Get relayd reference if exists. */
729 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
730 if (relayd
!= NULL
) {
731 /* Add stream on the relayd */
732 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
733 ret
= relayd_add_stream(&relayd
->control_sock
, stream
->name
,
734 path
, &stream
->relayd_stream_id
,
735 stream
->chan
->tracefile_size
, stream
->chan
->tracefile_count
);
736 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
741 uatomic_inc(&relayd
->refcount
);
742 stream
->sent_to_relayd
= 1;
744 ERR("Stream %" PRIu64
" relayd ID %" PRIu64
" unknown. Can't send it.",
745 stream
->key
, stream
->net_seq_idx
);
750 DBG("Stream %s with key %" PRIu64
" sent to relayd id %" PRIu64
,
751 stream
->name
, stream
->key
, stream
->net_seq_idx
);
759 * Find a relayd and close the stream
761 void close_relayd_stream(struct lttng_consumer_stream
*stream
)
763 struct consumer_relayd_sock_pair
*relayd
;
765 /* The stream is not metadata. Get relayd reference if exists. */
767 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
769 consumer_stream_relayd_close(stream
, relayd
);
775 * Handle stream for relayd transmission if the stream applies for network
776 * streaming where the net sequence index is set.
778 * Return destination file descriptor or negative value on error.
780 static int write_relayd_stream_header(struct lttng_consumer_stream
*stream
,
781 size_t data_size
, unsigned long padding
,
782 struct consumer_relayd_sock_pair
*relayd
)
785 struct lttcomm_relayd_data_hdr data_hdr
;
791 /* Reset data header */
792 memset(&data_hdr
, 0, sizeof(data_hdr
));
794 if (stream
->metadata_flag
) {
795 /* Caller MUST acquire the relayd control socket lock */
796 ret
= relayd_send_metadata(&relayd
->control_sock
, data_size
);
801 /* Metadata are always sent on the control socket. */
802 outfd
= relayd
->control_sock
.sock
.fd
;
804 /* Set header with stream information */
805 data_hdr
.stream_id
= htobe64(stream
->relayd_stream_id
);
806 data_hdr
.data_size
= htobe32(data_size
);
807 data_hdr
.padding_size
= htobe32(padding
);
809 * Note that net_seq_num below is assigned with the *current* value of
810 * next_net_seq_num and only after that the next_net_seq_num will be
811 * increment. This is why when issuing a command on the relayd using
812 * this next value, 1 should always be substracted in order to compare
813 * the last seen sequence number on the relayd side to the last sent.
815 data_hdr
.net_seq_num
= htobe64(stream
->next_net_seq_num
);
816 /* Other fields are zeroed previously */
818 ret
= relayd_send_data_hdr(&relayd
->data_sock
, &data_hdr
,
824 ++stream
->next_net_seq_num
;
826 /* Set to go on data socket */
827 outfd
= relayd
->data_sock
.sock
.fd
;
835 * Allocate and return a new lttng_consumer_channel object using the given key
836 * to initialize the hash table node.
838 * On error, return NULL.
840 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
842 const char *pathname
,
847 enum lttng_event_output output
,
848 uint64_t tracefile_size
,
849 uint64_t tracefile_count
,
850 uint64_t session_id_per_pid
,
851 unsigned int monitor
,
852 unsigned int live_timer_interval
)
854 struct lttng_consumer_channel
*channel
;
856 channel
= zmalloc(sizeof(*channel
));
857 if (channel
== NULL
) {
858 PERROR("malloc struct lttng_consumer_channel");
863 channel
->refcount
= 0;
864 channel
->session_id
= session_id
;
865 channel
->session_id_per_pid
= session_id_per_pid
;
868 channel
->relayd_id
= relayd_id
;
869 channel
->output
= output
;
870 channel
->tracefile_size
= tracefile_size
;
871 channel
->tracefile_count
= tracefile_count
;
872 channel
->monitor
= monitor
;
873 channel
->live_timer_interval
= live_timer_interval
;
874 pthread_mutex_init(&channel
->lock
, NULL
);
875 pthread_mutex_init(&channel
->timer_lock
, NULL
);
878 * In monitor mode, the streams associated with the channel will be put in
879 * a special list ONLY owned by this channel. So, the refcount is set to 1
880 * here meaning that the channel itself has streams that are referenced.
882 * On a channel deletion, once the channel is no longer visible, the
883 * refcount is decremented and checked for a zero value to delete it. With
884 * streams in no monitor mode, it will now be safe to destroy the channel.
886 if (!channel
->monitor
) {
887 channel
->refcount
= 1;
890 strncpy(channel
->pathname
, pathname
, sizeof(channel
->pathname
));
891 channel
->pathname
[sizeof(channel
->pathname
) - 1] = '\0';
893 strncpy(channel
->name
, name
, sizeof(channel
->name
));
894 channel
->name
[sizeof(channel
->name
) - 1] = '\0';
896 lttng_ht_node_init_u64(&channel
->node
, channel
->key
);
898 channel
->wait_fd
= -1;
900 CDS_INIT_LIST_HEAD(&channel
->streams
.head
);
902 DBG("Allocated channel (key %" PRIu64
")", channel
->key
)
909 * Add a channel to the global list protected by a mutex.
911 * On success 0 is returned else a negative value.
913 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
914 struct lttng_consumer_local_data
*ctx
)
917 struct lttng_ht_node_u64
*node
;
918 struct lttng_ht_iter iter
;
920 pthread_mutex_lock(&consumer_data
.lock
);
921 pthread_mutex_lock(&channel
->lock
);
922 pthread_mutex_lock(&channel
->timer_lock
);
925 lttng_ht_lookup(consumer_data
.channel_ht
, &channel
->key
, &iter
);
926 node
= lttng_ht_iter_get_node_u64(&iter
);
928 /* Channel already exist. Ignore the insertion */
929 ERR("Consumer add channel key %" PRIu64
" already exists!",
935 lttng_ht_add_unique_u64(consumer_data
.channel_ht
, &channel
->node
);
939 pthread_mutex_unlock(&channel
->timer_lock
);
940 pthread_mutex_unlock(&channel
->lock
);
941 pthread_mutex_unlock(&consumer_data
.lock
);
943 if (!ret
&& channel
->wait_fd
!= -1 &&
944 channel
->type
== CONSUMER_CHANNEL_TYPE_DATA
) {
945 notify_channel_pipe(ctx
, channel
, -1, CONSUMER_CHANNEL_ADD
);
951 * Allocate the pollfd structure and the local view of the out fds to avoid
952 * doing a lookup in the linked list and concurrency issues when writing is
953 * needed. Called with consumer_data.lock held.
955 * Returns the number of fds in the structures.
957 static int update_poll_array(struct lttng_consumer_local_data
*ctx
,
958 struct pollfd
**pollfd
, struct lttng_consumer_stream
**local_stream
,
962 struct lttng_ht_iter iter
;
963 struct lttng_consumer_stream
*stream
;
968 assert(local_stream
);
970 DBG("Updating poll fd array");
972 cds_lfht_for_each_entry(ht
->ht
, &iter
.iter
, stream
, node
.node
) {
974 * Only active streams with an active end point can be added to the
975 * poll set and local stream storage of the thread.
977 * There is a potential race here for endpoint_status to be updated
978 * just after the check. However, this is OK since the stream(s) will
979 * be deleted once the thread is notified that the end point state has
980 * changed where this function will be called back again.
982 if (stream
->state
!= LTTNG_CONSUMER_ACTIVE_STREAM
||
983 stream
->endpoint_status
== CONSUMER_ENDPOINT_INACTIVE
) {
987 * This clobbers way too much the debug output. Uncomment that if you
988 * need it for debugging purposes.
990 * DBG("Active FD %d", stream->wait_fd);
992 (*pollfd
)[i
].fd
= stream
->wait_fd
;
993 (*pollfd
)[i
].events
= POLLIN
| POLLPRI
;
994 local_stream
[i
] = stream
;
1000 * Insert the consumer_data_pipe at the end of the array and don't
1001 * increment i so nb_fd is the number of real FD.
1003 (*pollfd
)[i
].fd
= lttng_pipe_get_readfd(ctx
->consumer_data_pipe
);
1004 (*pollfd
)[i
].events
= POLLIN
| POLLPRI
;
1009 * Poll on the should_quit pipe and the command socket return -1 on error and
1010 * should exit, 0 if data is available on the command socket
1012 int lttng_consumer_poll_socket(struct pollfd
*consumer_sockpoll
)
1017 num_rdy
= poll(consumer_sockpoll
, 2, -1);
1018 if (num_rdy
== -1) {
1020 * Restart interrupted system call.
1022 if (errno
== EINTR
) {
1025 PERROR("Poll error");
1028 if (consumer_sockpoll
[0].revents
& (POLLIN
| POLLPRI
)) {
1029 DBG("consumer_should_quit wake up");
1039 * Set the error socket.
1041 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
1044 ctx
->consumer_error_socket
= sock
;
1048 * Set the command socket path.
1050 void lttng_consumer_set_command_sock_path(
1051 struct lttng_consumer_local_data
*ctx
, char *sock
)
1053 ctx
->consumer_command_sock_path
= sock
;
1057 * Send return code to the session daemon.
1058 * If the socket is not defined, we return 0, it is not a fatal error
1060 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
)
1062 if (ctx
->consumer_error_socket
> 0) {
1063 return lttcomm_send_unix_sock(ctx
->consumer_error_socket
, &cmd
,
1064 sizeof(enum lttcomm_sessiond_command
));
1071 * Close all the tracefiles and stream fds and MUST be called when all
1072 * instances are destroyed i.e. when all threads were joined and are ended.
1074 void lttng_consumer_cleanup(void)
1076 struct lttng_ht_iter iter
;
1077 struct lttng_consumer_channel
*channel
;
1081 cds_lfht_for_each_entry(consumer_data
.channel_ht
->ht
, &iter
.iter
, channel
,
1083 consumer_del_channel(channel
);
1088 lttng_ht_destroy(consumer_data
.channel_ht
);
1090 cleanup_relayd_ht();
1092 lttng_ht_destroy(consumer_data
.stream_per_chan_id_ht
);
1095 * This HT contains streams that are freed by either the metadata thread or
1096 * the data thread so we do *nothing* on the hash table and simply destroy
1099 lttng_ht_destroy(consumer_data
.stream_list_ht
);
1103 * Called from signal handler.
1105 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
)
1110 ret
= write(ctx
->consumer_should_quit
[1], "4", 1);
1111 } while (ret
< 0 && errno
== EINTR
);
1112 if (ret
< 0 || ret
!= 1) {
1113 PERROR("write consumer quit");
1116 DBG("Consumer flag that it should quit");
1119 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
1122 int outfd
= stream
->out_fd
;
1125 * This does a blocking write-and-wait on any page that belongs to the
1126 * subbuffer prior to the one we just wrote.
1127 * Don't care about error values, as these are just hints and ways to
1128 * limit the amount of page cache used.
1130 if (orig_offset
< stream
->max_sb_size
) {
1133 lttng_sync_file_range(outfd
, orig_offset
- stream
->max_sb_size
,
1134 stream
->max_sb_size
,
1135 SYNC_FILE_RANGE_WAIT_BEFORE
1136 | SYNC_FILE_RANGE_WRITE
1137 | SYNC_FILE_RANGE_WAIT_AFTER
);
1139 * Give hints to the kernel about how we access the file:
1140 * POSIX_FADV_DONTNEED : we won't re-access data in a near future after
1143 * We need to call fadvise again after the file grows because the
1144 * kernel does not seem to apply fadvise to non-existing parts of the
1147 * Call fadvise _after_ having waited for the page writeback to
1148 * complete because the dirty page writeback semantic is not well
1149 * defined. So it can be expected to lead to lower throughput in
1152 posix_fadvise(outfd
, orig_offset
- stream
->max_sb_size
,
1153 stream
->max_sb_size
, POSIX_FADV_DONTNEED
);
1157 * Initialise the necessary environnement :
1158 * - create a new context
1159 * - create the poll_pipe
1160 * - create the should_quit pipe (for signal handler)
1161 * - create the thread pipe (for splice)
1163 * Takes a function pointer as argument, this function is called when data is
1164 * available on a buffer. This function is responsible to do the
1165 * kernctl_get_next_subbuf, read the data with mmap or splice depending on the
1166 * buffer configuration and then kernctl_put_next_subbuf at the end.
1168 * Returns a pointer to the new context or NULL on error.
1170 struct lttng_consumer_local_data
*lttng_consumer_create(
1171 enum lttng_consumer_type type
,
1172 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
1173 struct lttng_consumer_local_data
*ctx
),
1174 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
1175 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
1176 int (*update_stream
)(uint64_t stream_key
, uint32_t state
))
1179 struct lttng_consumer_local_data
*ctx
;
1181 assert(consumer_data
.type
== LTTNG_CONSUMER_UNKNOWN
||
1182 consumer_data
.type
== type
);
1183 consumer_data
.type
= type
;
1185 ctx
= zmalloc(sizeof(struct lttng_consumer_local_data
));
1187 PERROR("allocating context");
1191 ctx
->consumer_error_socket
= -1;
1192 ctx
->consumer_metadata_socket
= -1;
1193 pthread_mutex_init(&ctx
->metadata_socket_lock
, NULL
);
1194 /* assign the callbacks */
1195 ctx
->on_buffer_ready
= buffer_ready
;
1196 ctx
->on_recv_channel
= recv_channel
;
1197 ctx
->on_recv_stream
= recv_stream
;
1198 ctx
->on_update_stream
= update_stream
;
1200 ctx
->consumer_data_pipe
= lttng_pipe_open(0);
1201 if (!ctx
->consumer_data_pipe
) {
1202 goto error_poll_pipe
;
1205 ret
= pipe(ctx
->consumer_should_quit
);
1207 PERROR("Error creating recv pipe");
1208 goto error_quit_pipe
;
1211 ret
= pipe(ctx
->consumer_thread_pipe
);
1213 PERROR("Error creating thread pipe");
1214 goto error_thread_pipe
;
1217 ret
= pipe(ctx
->consumer_channel_pipe
);
1219 PERROR("Error creating channel pipe");
1220 goto error_channel_pipe
;
1223 ctx
->consumer_metadata_pipe
= lttng_pipe_open(0);
1224 if (!ctx
->consumer_metadata_pipe
) {
1225 goto error_metadata_pipe
;
1228 ret
= utils_create_pipe(ctx
->consumer_splice_metadata_pipe
);
1230 goto error_splice_pipe
;
1236 lttng_pipe_destroy(ctx
->consumer_metadata_pipe
);
1237 error_metadata_pipe
:
1238 utils_close_pipe(ctx
->consumer_channel_pipe
);
1240 utils_close_pipe(ctx
->consumer_thread_pipe
);
1242 utils_close_pipe(ctx
->consumer_should_quit
);
1244 lttng_pipe_destroy(ctx
->consumer_data_pipe
);
1252 * Close all fds associated with the instance and free the context.
1254 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
)
1258 DBG("Consumer destroying it. Closing everything.");
1260 ret
= close(ctx
->consumer_error_socket
);
1264 ret
= close(ctx
->consumer_metadata_socket
);
1268 utils_close_pipe(ctx
->consumer_thread_pipe
);
1269 utils_close_pipe(ctx
->consumer_channel_pipe
);
1270 lttng_pipe_destroy(ctx
->consumer_data_pipe
);
1271 lttng_pipe_destroy(ctx
->consumer_metadata_pipe
);
1272 utils_close_pipe(ctx
->consumer_should_quit
);
1273 utils_close_pipe(ctx
->consumer_splice_metadata_pipe
);
1275 unlink(ctx
->consumer_command_sock_path
);
1280 * Write the metadata stream id on the specified file descriptor.
1282 static int write_relayd_metadata_id(int fd
,
1283 struct lttng_consumer_stream
*stream
,
1284 struct consumer_relayd_sock_pair
*relayd
, unsigned long padding
)
1287 struct lttcomm_relayd_metadata_payload hdr
;
1289 hdr
.stream_id
= htobe64(stream
->relayd_stream_id
);
1290 hdr
.padding_size
= htobe32(padding
);
1292 ret
= write(fd
, (void *) &hdr
, sizeof(hdr
));
1293 } while (ret
< 0 && errno
== EINTR
);
1294 if (ret
< 0 || ret
!= sizeof(hdr
)) {
1296 * This error means that the fd's end is closed so ignore the perror
1297 * not to clubber the error output since this can happen in a normal
1300 if (errno
!= EPIPE
) {
1301 PERROR("write metadata stream id");
1303 DBG3("Consumer failed to write relayd metadata id (errno: %d)", errno
);
1305 * Set ret to a negative value because if ret != sizeof(hdr), we don't
1306 * handle writting the missing part so report that as an error and
1307 * don't lie to the caller.
1312 DBG("Metadata stream id %" PRIu64
" with padding %lu written before data",
1313 stream
->relayd_stream_id
, padding
);
1320 * Mmap the ring buffer, read it and write the data to the tracefile. This is a
1321 * core function for writing trace buffers to either the local filesystem or
1324 * It must be called with the stream lock held.
1326 * Careful review MUST be put if any changes occur!
1328 * Returns the number of bytes written
1330 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
1331 struct lttng_consumer_local_data
*ctx
,
1332 struct lttng_consumer_stream
*stream
, unsigned long len
,
1333 unsigned long padding
,
1334 struct lttng_packet_index
*index
)
1336 unsigned long mmap_offset
;
1338 ssize_t ret
= 0, written
= 0;
1339 off_t orig_offset
= stream
->out_fd_offset
;
1340 /* Default is on the disk */
1341 int outfd
= stream
->out_fd
;
1342 struct consumer_relayd_sock_pair
*relayd
= NULL
;
1343 unsigned int relayd_hang_up
= 0;
1345 /* RCU lock for the relayd pointer */
1348 /* Flag that the current stream if set for network streaming. */
1349 if (stream
->net_seq_idx
!= (uint64_t) -1ULL) {
1350 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
1351 if (relayd
== NULL
) {
1357 /* get the offset inside the fd to mmap */
1358 switch (consumer_data
.type
) {
1359 case LTTNG_CONSUMER_KERNEL
:
1360 mmap_base
= stream
->mmap_base
;
1361 ret
= kernctl_get_mmap_read_offset(stream
->wait_fd
, &mmap_offset
);
1363 PERROR("tracer ctl get_mmap_read_offset");
1368 case LTTNG_CONSUMER32_UST
:
1369 case LTTNG_CONSUMER64_UST
:
1370 mmap_base
= lttng_ustctl_get_mmap_base(stream
);
1372 ERR("read mmap get mmap base for stream %s", stream
->name
);
1376 ret
= lttng_ustctl_get_mmap_read_offset(stream
, &mmap_offset
);
1378 PERROR("tracer ctl get_mmap_read_offset");
1384 ERR("Unknown consumer_data type");
1388 /* Handle stream on the relayd if the output is on the network */
1390 unsigned long netlen
= len
;
1393 * Lock the control socket for the complete duration of the function
1394 * since from this point on we will use the socket.
1396 if (stream
->metadata_flag
) {
1397 /* Metadata requires the control socket. */
1398 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
1399 netlen
+= sizeof(struct lttcomm_relayd_metadata_payload
);
1402 ret
= write_relayd_stream_header(stream
, netlen
, padding
, relayd
);
1404 /* Use the returned socket. */
1407 /* Write metadata stream id before payload */
1408 if (stream
->metadata_flag
) {
1409 ret
= write_relayd_metadata_id(outfd
, stream
, relayd
, padding
);
1412 /* Socket operation failed. We consider the relayd dead */
1413 if (ret
== -EPIPE
|| ret
== -EINVAL
) {
1421 /* Socket operation failed. We consider the relayd dead */
1422 if (ret
== -EPIPE
|| ret
== -EINVAL
) {
1426 /* Else, use the default set before which is the filesystem. */
1429 /* No streaming, we have to set the len with the full padding */
1433 * Check if we need to change the tracefile before writing the packet.
1435 if (stream
->chan
->tracefile_size
> 0 &&
1436 (stream
->tracefile_size_current
+ len
) >
1437 stream
->chan
->tracefile_size
) {
1438 ret
= utils_rotate_stream_file(stream
->chan
->pathname
,
1439 stream
->name
, stream
->chan
->tracefile_size
,
1440 stream
->chan
->tracefile_count
, stream
->uid
, stream
->gid
,
1441 stream
->out_fd
, &(stream
->tracefile_count_current
),
1444 ERR("Rotating output file");
1447 outfd
= stream
->out_fd
;
1449 if (stream
->index_fd
>= 0) {
1450 ret
= index_create_file(stream
->chan
->pathname
,
1451 stream
->name
, stream
->uid
, stream
->gid
,
1452 stream
->chan
->tracefile_size
,
1453 stream
->tracefile_count_current
);
1457 stream
->index_fd
= ret
;
1460 /* Reset current size because we just perform a rotation. */
1461 stream
->tracefile_size_current
= 0;
1462 stream
->out_fd_offset
= 0;
1465 stream
->tracefile_size_current
+= len
;
1467 index
->offset
= htobe64(stream
->out_fd_offset
);
1473 ret
= write(outfd
, mmap_base
+ mmap_offset
, len
);
1474 } while (ret
< 0 && errno
== EINTR
);
1475 DBG("Consumer mmap write() ret %zd (len %lu)", ret
, len
);
1478 * This is possible if the fd is closed on the other side (outfd)
1479 * or any write problem. It can be verbose a bit for a normal
1480 * execution if for instance the relayd is stopped abruptly. This
1481 * can happen so set this to a DBG statement.
1483 DBG("Error in file write mmap");
1487 /* Socket operation failed. We consider the relayd dead */
1488 if (errno
== EPIPE
|| errno
== EINVAL
) {
1493 } else if (ret
> len
) {
1494 PERROR("Error in file write (ret %zd > len %lu)", ret
, len
);
1502 /* This call is useless on a socket so better save a syscall. */
1504 /* This won't block, but will start writeout asynchronously */
1505 lttng_sync_file_range(outfd
, stream
->out_fd_offset
, ret
,
1506 SYNC_FILE_RANGE_WRITE
);
1507 stream
->out_fd_offset
+= ret
;
1509 stream
->output_written
+= ret
;
1512 lttng_consumer_sync_trace_file(stream
, orig_offset
);
1516 * This is a special case that the relayd has closed its socket. Let's
1517 * cleanup the relayd object and all associated streams.
1519 if (relayd
&& relayd_hang_up
) {
1520 cleanup_relayd(relayd
, ctx
);
1524 /* Unlock only if ctrl socket used */
1525 if (relayd
&& stream
->metadata_flag
) {
1526 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
1534 * Splice the data from the ring buffer to the tracefile.
1536 * It must be called with the stream lock held.
1538 * Returns the number of bytes spliced.
1540 ssize_t
lttng_consumer_on_read_subbuffer_splice(
1541 struct lttng_consumer_local_data
*ctx
,
1542 struct lttng_consumer_stream
*stream
, unsigned long len
,
1543 unsigned long padding
,
1544 struct lttng_packet_index
*index
)
1546 ssize_t ret
= 0, written
= 0, ret_splice
= 0;
1548 off_t orig_offset
= stream
->out_fd_offset
;
1549 int fd
= stream
->wait_fd
;
1550 /* Default is on the disk */
1551 int outfd
= stream
->out_fd
;
1552 struct consumer_relayd_sock_pair
*relayd
= NULL
;
1554 unsigned int relayd_hang_up
= 0;
1556 switch (consumer_data
.type
) {
1557 case LTTNG_CONSUMER_KERNEL
:
1559 case LTTNG_CONSUMER32_UST
:
1560 case LTTNG_CONSUMER64_UST
:
1561 /* Not supported for user space tracing */
1564 ERR("Unknown consumer_data type");
1568 /* RCU lock for the relayd pointer */
1571 /* Flag that the current stream if set for network streaming. */
1572 if (stream
->net_seq_idx
!= (uint64_t) -1ULL) {
1573 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
1574 if (relayd
== NULL
) {
1581 * Choose right pipe for splice. Metadata and trace data are handled by
1582 * different threads hence the use of two pipes in order not to race or
1583 * corrupt the written data.
1585 if (stream
->metadata_flag
) {
1586 splice_pipe
= ctx
->consumer_splice_metadata_pipe
;
1588 splice_pipe
= ctx
->consumer_thread_pipe
;
1591 /* Write metadata stream id before payload */
1593 int total_len
= len
;
1595 if (stream
->metadata_flag
) {
1597 * Lock the control socket for the complete duration of the function
1598 * since from this point on we will use the socket.
1600 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
1602 ret
= write_relayd_metadata_id(splice_pipe
[1], stream
, relayd
,
1606 /* Socket operation failed. We consider the relayd dead */
1607 if (ret
== -EBADF
) {
1608 WARN("Remote relayd disconnected. Stopping");
1615 total_len
+= sizeof(struct lttcomm_relayd_metadata_payload
);
1618 ret
= write_relayd_stream_header(stream
, total_len
, padding
, relayd
);
1620 /* Use the returned socket. */
1623 /* Socket operation failed. We consider the relayd dead */
1624 if (ret
== -EBADF
) {
1625 WARN("Remote relayd disconnected. Stopping");
1632 /* No streaming, we have to set the len with the full padding */
1636 * Check if we need to change the tracefile before writing the packet.
1638 if (stream
->chan
->tracefile_size
> 0 &&
1639 (stream
->tracefile_size_current
+ len
) >
1640 stream
->chan
->tracefile_size
) {
1641 ret
= utils_rotate_stream_file(stream
->chan
->pathname
,
1642 stream
->name
, stream
->chan
->tracefile_size
,
1643 stream
->chan
->tracefile_count
, stream
->uid
, stream
->gid
,
1644 stream
->out_fd
, &(stream
->tracefile_count_current
),
1647 ERR("Rotating output file");
1650 outfd
= stream
->out_fd
;
1652 if (stream
->index_fd
>= 0) {
1653 ret
= index_create_file(stream
->chan
->pathname
,
1654 stream
->name
, stream
->uid
, stream
->gid
,
1655 stream
->chan
->tracefile_size
,
1656 stream
->tracefile_count_current
);
1660 stream
->index_fd
= ret
;
1663 /* Reset current size because we just perform a rotation. */
1664 stream
->tracefile_size_current
= 0;
1665 stream
->out_fd_offset
= 0;
1668 stream
->tracefile_size_current
+= len
;
1669 index
->offset
= htobe64(stream
->out_fd_offset
);
1673 DBG("splice chan to pipe offset %lu of len %lu (fd : %d, pipe: %d)",
1674 (unsigned long)offset
, len
, fd
, splice_pipe
[1]);
1675 ret_splice
= splice(fd
, &offset
, splice_pipe
[1], NULL
, len
,
1676 SPLICE_F_MOVE
| SPLICE_F_MORE
);
1677 DBG("splice chan to pipe, ret %zd", ret_splice
);
1678 if (ret_splice
< 0) {
1679 PERROR("Error in relay splice");
1681 written
= ret_splice
;
1687 /* Handle stream on the relayd if the output is on the network */
1689 if (stream
->metadata_flag
) {
1690 size_t metadata_payload_size
=
1691 sizeof(struct lttcomm_relayd_metadata_payload
);
1693 /* Update counter to fit the spliced data */
1694 ret_splice
+= metadata_payload_size
;
1695 len
+= metadata_payload_size
;
1697 * We do this so the return value can match the len passed as
1698 * argument to this function.
1700 written
-= metadata_payload_size
;
1704 /* Splice data out */
1705 ret_splice
= splice(splice_pipe
[0], NULL
, outfd
, NULL
,
1706 ret_splice
, SPLICE_F_MOVE
| SPLICE_F_MORE
);
1707 DBG("Consumer splice pipe to file, ret %zd", ret_splice
);
1708 if (ret_splice
< 0) {
1709 PERROR("Error in file splice");
1711 written
= ret_splice
;
1713 /* Socket operation failed. We consider the relayd dead */
1714 if (errno
== EBADF
|| errno
== EPIPE
) {
1715 WARN("Remote relayd disconnected. Stopping");
1721 } else if (ret_splice
> len
) {
1723 PERROR("Wrote more data than requested %zd (len: %lu)",
1725 written
+= ret_splice
;
1731 /* This call is useless on a socket so better save a syscall. */
1733 /* This won't block, but will start writeout asynchronously */
1734 lttng_sync_file_range(outfd
, stream
->out_fd_offset
, ret_splice
,
1735 SYNC_FILE_RANGE_WRITE
);
1736 stream
->out_fd_offset
+= ret_splice
;
1738 stream
->output_written
+= ret_splice
;
1739 written
+= ret_splice
;
1741 lttng_consumer_sync_trace_file(stream
, orig_offset
);
1749 * This is a special case that the relayd has closed its socket. Let's
1750 * cleanup the relayd object and all associated streams.
1752 if (relayd
&& relayd_hang_up
) {
1753 cleanup_relayd(relayd
, ctx
);
1754 /* Skip splice error so the consumer does not fail */
1759 /* send the appropriate error description to sessiond */
1762 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_SPLICE_EINVAL
);
1765 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_SPLICE_ENOMEM
);
1768 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_SPLICE_ESPIPE
);
1773 if (relayd
&& stream
->metadata_flag
) {
1774 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
1782 * Take a snapshot for a specific fd
1784 * Returns 0 on success, < 0 on error
1786 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1788 switch (consumer_data
.type
) {
1789 case LTTNG_CONSUMER_KERNEL
:
1790 return lttng_kconsumer_take_snapshot(stream
);
1791 case LTTNG_CONSUMER32_UST
:
1792 case LTTNG_CONSUMER64_UST
:
1793 return lttng_ustconsumer_take_snapshot(stream
);
1795 ERR("Unknown consumer_data type");
1802 * Get the produced position
1804 * Returns 0 on success, < 0 on error
1806 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
1809 switch (consumer_data
.type
) {
1810 case LTTNG_CONSUMER_KERNEL
:
1811 return lttng_kconsumer_get_produced_snapshot(stream
, pos
);
1812 case LTTNG_CONSUMER32_UST
:
1813 case LTTNG_CONSUMER64_UST
:
1814 return lttng_ustconsumer_get_produced_snapshot(stream
, pos
);
1816 ERR("Unknown consumer_data type");
1822 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1823 int sock
, struct pollfd
*consumer_sockpoll
)
1825 switch (consumer_data
.type
) {
1826 case LTTNG_CONSUMER_KERNEL
:
1827 return lttng_kconsumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
1828 case LTTNG_CONSUMER32_UST
:
1829 case LTTNG_CONSUMER64_UST
:
1830 return lttng_ustconsumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
1832 ERR("Unknown consumer_data type");
1839 * Iterate over all streams of the hashtable and free them properly.
1841 * WARNING: *MUST* be used with data stream only.
1843 static void destroy_data_stream_ht(struct lttng_ht
*ht
)
1845 struct lttng_ht_iter iter
;
1846 struct lttng_consumer_stream
*stream
;
1853 cds_lfht_for_each_entry(ht
->ht
, &iter
.iter
, stream
, node
.node
) {
1855 * Ignore return value since we are currently cleaning up so any error
1858 (void) consumer_del_stream(stream
, ht
);
1862 lttng_ht_destroy(ht
);
1866 * Iterate over all streams of the hashtable and free them properly.
1868 * XXX: Should not be only for metadata stream or else use an other name.
1870 static void destroy_stream_ht(struct lttng_ht
*ht
)
1872 struct lttng_ht_iter iter
;
1873 struct lttng_consumer_stream
*stream
;
1880 cds_lfht_for_each_entry(ht
->ht
, &iter
.iter
, stream
, node
.node
) {
1882 * Ignore return value since we are currently cleaning up so any error
1885 (void) consumer_del_metadata_stream(stream
, ht
);
1889 lttng_ht_destroy(ht
);
1892 void lttng_consumer_close_metadata(void)
1894 switch (consumer_data
.type
) {
1895 case LTTNG_CONSUMER_KERNEL
:
1897 * The Kernel consumer has a different metadata scheme so we don't
1898 * close anything because the stream will be closed by the session
1902 case LTTNG_CONSUMER32_UST
:
1903 case LTTNG_CONSUMER64_UST
:
1905 * Close all metadata streams. The metadata hash table is passed and
1906 * this call iterates over it by closing all wakeup fd. This is safe
1907 * because at this point we are sure that the metadata producer is
1908 * either dead or blocked.
1910 lttng_ustconsumer_close_metadata(metadata_ht
);
1913 ERR("Unknown consumer_data type");
1919 * Clean up a metadata stream and free its memory.
1921 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
1922 struct lttng_ht
*ht
)
1925 struct lttng_ht_iter iter
;
1926 struct lttng_consumer_channel
*free_chan
= NULL
;
1927 struct consumer_relayd_sock_pair
*relayd
;
1931 * This call should NEVER receive regular stream. It must always be
1932 * metadata stream and this is crucial for data structure synchronization.
1934 assert(stream
->metadata_flag
);
1936 DBG3("Consumer delete metadata stream %d", stream
->wait_fd
);
1939 /* Means the stream was allocated but not successfully added */
1940 goto free_stream_rcu
;
1943 pthread_mutex_lock(&consumer_data
.lock
);
1944 pthread_mutex_lock(&stream
->chan
->lock
);
1945 pthread_mutex_lock(&stream
->lock
);
1947 switch (consumer_data
.type
) {
1948 case LTTNG_CONSUMER_KERNEL
:
1949 if (stream
->mmap_base
!= NULL
) {
1950 ret
= munmap(stream
->mmap_base
, stream
->mmap_len
);
1952 PERROR("munmap metadata stream");
1955 if (stream
->wait_fd
>= 0) {
1956 ret
= close(stream
->wait_fd
);
1958 PERROR("close kernel metadata wait_fd");
1962 case LTTNG_CONSUMER32_UST
:
1963 case LTTNG_CONSUMER64_UST
:
1964 if (stream
->monitor
) {
1965 /* close the write-side in close_metadata */
1966 ret
= close(stream
->ust_metadata_poll_pipe
[0]);
1968 PERROR("Close UST metadata read-side poll pipe");
1971 lttng_ustconsumer_del_stream(stream
);
1974 ERR("Unknown consumer_data type");
1980 iter
.iter
.node
= &stream
->node
.node
;
1981 ret
= lttng_ht_del(ht
, &iter
);
1984 iter
.iter
.node
= &stream
->node_channel_id
.node
;
1985 ret
= lttng_ht_del(consumer_data
.stream_per_chan_id_ht
, &iter
);
1988 iter
.iter
.node
= &stream
->node_session_id
.node
;
1989 ret
= lttng_ht_del(consumer_data
.stream_list_ht
, &iter
);
1993 if (stream
->out_fd
>= 0) {
1994 ret
= close(stream
->out_fd
);
2000 /* Check and cleanup relayd */
2002 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
2003 if (relayd
!= NULL
) {
2004 uatomic_dec(&relayd
->refcount
);
2005 assert(uatomic_read(&relayd
->refcount
) >= 0);
2007 /* Closing streams requires to lock the control socket. */
2008 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
2009 ret
= relayd_send_close_stream(&relayd
->control_sock
,
2010 stream
->relayd_stream_id
, stream
->next_net_seq_num
- 1);
2011 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
2013 DBG("Unable to close stream on the relayd. Continuing");
2015 * Continue here. There is nothing we can do for the relayd.
2016 * Chances are that the relayd has closed the socket so we just
2017 * continue cleaning up.
2021 /* Both conditions are met, we destroy the relayd. */
2022 if (uatomic_read(&relayd
->refcount
) == 0 &&
2023 uatomic_read(&relayd
->destroy_flag
)) {
2024 consumer_destroy_relayd(relayd
);
2029 /* Atomically decrement channel refcount since other threads can use it. */
2030 if (!uatomic_sub_return(&stream
->chan
->refcount
, 1)
2031 && !uatomic_read(&stream
->chan
->nb_init_stream_left
)) {
2032 /* Go for channel deletion! */
2033 free_chan
= stream
->chan
;
2038 * Nullify the stream reference so it is not used after deletion. The
2039 * channel lock MUST be acquired before being able to check for
2040 * a NULL pointer value.
2042 stream
->chan
->metadata_stream
= NULL
;
2044 pthread_mutex_unlock(&stream
->lock
);
2045 pthread_mutex_unlock(&stream
->chan
->lock
);
2046 pthread_mutex_unlock(&consumer_data
.lock
);
2049 consumer_del_channel(free_chan
);
2053 call_rcu(&stream
->node
.head
, free_stream_rcu
);
2057 * Action done with the metadata stream when adding it to the consumer internal
2058 * data structures to handle it.
2060 int consumer_add_metadata_stream(struct lttng_consumer_stream
*stream
)
2062 struct lttng_ht
*ht
= metadata_ht
;
2064 struct lttng_ht_iter iter
;
2065 struct lttng_ht_node_u64
*node
;
2070 DBG3("Adding metadata stream %" PRIu64
" to hash table", stream
->key
);
2072 pthread_mutex_lock(&consumer_data
.lock
);
2073 pthread_mutex_lock(&stream
->chan
->lock
);
2074 pthread_mutex_lock(&stream
->chan
->timer_lock
);
2075 pthread_mutex_lock(&stream
->lock
);
2078 * From here, refcounts are updated so be _careful_ when returning an error
2085 * Lookup the stream just to make sure it does not exist in our internal
2086 * state. This should NEVER happen.
2088 lttng_ht_lookup(ht
, &stream
->key
, &iter
);
2089 node
= lttng_ht_iter_get_node_u64(&iter
);
2093 * When nb_init_stream_left reaches 0, we don't need to trigger any action
2094 * in terms of destroying the associated channel, because the action that
2095 * causes the count to become 0 also causes a stream to be added. The
2096 * channel deletion will thus be triggered by the following removal of this
2099 if (uatomic_read(&stream
->chan
->nb_init_stream_left
) > 0) {
2100 /* Increment refcount before decrementing nb_init_stream_left */
2102 uatomic_dec(&stream
->chan
->nb_init_stream_left
);
2105 lttng_ht_add_unique_u64(ht
, &stream
->node
);
2107 lttng_ht_add_unique_u64(consumer_data
.stream_per_chan_id_ht
,
2108 &stream
->node_channel_id
);
2111 * Add stream to the stream_list_ht of the consumer data. No need to steal
2112 * the key since the HT does not use it and we allow to add redundant keys
2115 lttng_ht_add_u64(consumer_data
.stream_list_ht
, &stream
->node_session_id
);
2119 pthread_mutex_unlock(&stream
->lock
);
2120 pthread_mutex_unlock(&stream
->chan
->lock
);
2121 pthread_mutex_unlock(&stream
->chan
->timer_lock
);
2122 pthread_mutex_unlock(&consumer_data
.lock
);
2127 * Delete data stream that are flagged for deletion (endpoint_status).
2129 static void validate_endpoint_status_data_stream(void)
2131 struct lttng_ht_iter iter
;
2132 struct lttng_consumer_stream
*stream
;
2134 DBG("Consumer delete flagged data stream");
2137 cds_lfht_for_each_entry(data_ht
->ht
, &iter
.iter
, stream
, node
.node
) {
2138 /* Validate delete flag of the stream */
2139 if (stream
->endpoint_status
== CONSUMER_ENDPOINT_ACTIVE
) {
2142 /* Delete it right now */
2143 consumer_del_stream(stream
, data_ht
);
2149 * Delete metadata stream that are flagged for deletion (endpoint_status).
2151 static void validate_endpoint_status_metadata_stream(
2152 struct lttng_poll_event
*pollset
)
2154 struct lttng_ht_iter iter
;
2155 struct lttng_consumer_stream
*stream
;
2157 DBG("Consumer delete flagged metadata stream");
2162 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
, node
.node
) {
2163 /* Validate delete flag of the stream */
2164 if (stream
->endpoint_status
== CONSUMER_ENDPOINT_ACTIVE
) {
2168 * Remove from pollset so the metadata thread can continue without
2169 * blocking on a deleted stream.
2171 lttng_poll_del(pollset
, stream
->wait_fd
);
2173 /* Delete it right now */
2174 consumer_del_metadata_stream(stream
, metadata_ht
);
2180 * Thread polls on metadata file descriptor and write them on disk or on the
2183 void *consumer_thread_metadata_poll(void *data
)
2186 uint32_t revents
, nb_fd
;
2187 struct lttng_consumer_stream
*stream
= NULL
;
2188 struct lttng_ht_iter iter
;
2189 struct lttng_ht_node_u64
*node
;
2190 struct lttng_poll_event events
;
2191 struct lttng_consumer_local_data
*ctx
= data
;
2194 rcu_register_thread();
2196 metadata_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
2198 /* ENOMEM at this point. Better to bail out. */
2202 DBG("Thread metadata poll started");
2204 /* Size is set to 1 for the consumer_metadata pipe */
2205 ret
= lttng_poll_create(&events
, 2, LTTNG_CLOEXEC
);
2207 ERR("Poll set creation failed");
2211 ret
= lttng_poll_add(&events
,
2212 lttng_pipe_get_readfd(ctx
->consumer_metadata_pipe
), LPOLLIN
);
2218 DBG("Metadata main loop started");
2221 /* Only the metadata pipe is set */
2222 if (LTTNG_POLL_GETNB(&events
) == 0 && consumer_quit
== 1) {
2227 DBG("Metadata poll wait with %d fd(s)", LTTNG_POLL_GETNB(&events
));
2228 ret
= lttng_poll_wait(&events
, -1);
2229 DBG("Metadata event catched in thread");
2231 if (errno
== EINTR
) {
2232 ERR("Poll EINTR catched");
2240 /* From here, the event is a metadata wait fd */
2241 for (i
= 0; i
< nb_fd
; i
++) {
2242 revents
= LTTNG_POLL_GETEV(&events
, i
);
2243 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2245 if (pollfd
== lttng_pipe_get_readfd(ctx
->consumer_metadata_pipe
)) {
2246 if (revents
& (LPOLLERR
| LPOLLHUP
)) {
2247 DBG("Metadata thread pipe hung up");
2249 * Remove the pipe from the poll set and continue the loop
2250 * since their might be data to consume.
2252 lttng_poll_del(&events
,
2253 lttng_pipe_get_readfd(ctx
->consumer_metadata_pipe
));
2254 lttng_pipe_read_close(ctx
->consumer_metadata_pipe
);
2256 } else if (revents
& LPOLLIN
) {
2259 pipe_len
= lttng_pipe_read(ctx
->consumer_metadata_pipe
,
2260 &stream
, sizeof(stream
));
2262 ERR("read metadata stream, ret: %zd", pipe_len
);
2264 * Continue here to handle the rest of the streams.
2269 /* A NULL stream means that the state has changed. */
2270 if (stream
== NULL
) {
2271 /* Check for deleted streams. */
2272 validate_endpoint_status_metadata_stream(&events
);
2276 DBG("Adding metadata stream %d to poll set",
2279 /* Add metadata stream to the global poll events list */
2280 lttng_poll_add(&events
, stream
->wait_fd
,
2281 LPOLLIN
| LPOLLPRI
);
2284 /* Handle other stream */
2290 uint64_t tmp_id
= (uint64_t) pollfd
;
2292 lttng_ht_lookup(metadata_ht
, &tmp_id
, &iter
);
2294 node
= lttng_ht_iter_get_node_u64(&iter
);
2297 stream
= caa_container_of(node
, struct lttng_consumer_stream
,
2300 /* Check for error event */
2301 if (revents
& (LPOLLERR
| LPOLLHUP
)) {
2302 DBG("Metadata fd %d is hup|err.", pollfd
);
2303 if (!stream
->hangup_flush_done
2304 && (consumer_data
.type
== LTTNG_CONSUMER32_UST
2305 || consumer_data
.type
== LTTNG_CONSUMER64_UST
)) {
2306 DBG("Attempting to flush and consume the UST buffers");
2307 lttng_ustconsumer_on_stream_hangup(stream
);
2309 /* We just flushed the stream now read it. */
2311 len
= ctx
->on_buffer_ready(stream
, ctx
);
2313 * We don't check the return value here since if we get
2314 * a negative len, it means an error occured thus we
2315 * simply remove it from the poll set and free the
2321 lttng_poll_del(&events
, stream
->wait_fd
);
2323 * This call update the channel states, closes file descriptors
2324 * and securely free the stream.
2326 consumer_del_metadata_stream(stream
, metadata_ht
);
2327 } else if (revents
& (LPOLLIN
| LPOLLPRI
)) {
2328 /* Get the data out of the metadata file descriptor */
2329 DBG("Metadata available on fd %d", pollfd
);
2330 assert(stream
->wait_fd
== pollfd
);
2333 len
= ctx
->on_buffer_ready(stream
, ctx
);
2335 * We don't check the return value here since if we get
2336 * a negative len, it means an error occured thus we
2337 * simply remove it from the poll set and free the
2342 /* It's ok to have an unavailable sub-buffer */
2343 if (len
< 0 && len
!= -EAGAIN
&& len
!= -ENODATA
) {
2344 /* Clean up stream from consumer and free it. */
2345 lttng_poll_del(&events
, stream
->wait_fd
);
2346 consumer_del_metadata_stream(stream
, metadata_ht
);
2350 /* Release RCU lock for the stream looked up */
2357 DBG("Metadata poll thread exiting");
2359 lttng_poll_clean(&events
);
2361 destroy_stream_ht(metadata_ht
);
2363 rcu_unregister_thread();
2368 * This thread polls the fds in the set to consume the data and write
2369 * it to tracefile if necessary.
2371 void *consumer_thread_data_poll(void *data
)
2373 int num_rdy
, num_hup
, high_prio
, ret
, i
;
2374 struct pollfd
*pollfd
= NULL
;
2375 /* local view of the streams */
2376 struct lttng_consumer_stream
**local_stream
= NULL
, *new_stream
= NULL
;
2377 /* local view of consumer_data.fds_count */
2379 struct lttng_consumer_local_data
*ctx
= data
;
2382 rcu_register_thread();
2384 data_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
2385 if (data_ht
== NULL
) {
2386 /* ENOMEM at this point. Better to bail out. */
2390 local_stream
= zmalloc(sizeof(struct lttng_consumer_stream
*));
2391 if (local_stream
== NULL
) {
2392 PERROR("local_stream malloc");
2401 * the fds set has been updated, we need to update our
2402 * local array as well
2404 pthread_mutex_lock(&consumer_data
.lock
);
2405 if (consumer_data
.need_update
) {
2410 local_stream
= NULL
;
2412 /* allocate for all fds + 1 for the consumer_data_pipe */
2413 pollfd
= zmalloc((consumer_data
.stream_count
+ 1) * sizeof(struct pollfd
));
2414 if (pollfd
== NULL
) {
2415 PERROR("pollfd malloc");
2416 pthread_mutex_unlock(&consumer_data
.lock
);
2420 /* allocate for all fds + 1 for the consumer_data_pipe */
2421 local_stream
= zmalloc((consumer_data
.stream_count
+ 1) *
2422 sizeof(struct lttng_consumer_stream
*));
2423 if (local_stream
== NULL
) {
2424 PERROR("local_stream malloc");
2425 pthread_mutex_unlock(&consumer_data
.lock
);
2428 ret
= update_poll_array(ctx
, &pollfd
, local_stream
,
2431 ERR("Error in allocating pollfd or local_outfds");
2432 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_POLL_ERROR
);
2433 pthread_mutex_unlock(&consumer_data
.lock
);
2437 consumer_data
.need_update
= 0;
2439 pthread_mutex_unlock(&consumer_data
.lock
);
2441 /* No FDs and consumer_quit, consumer_cleanup the thread */
2442 if (nb_fd
== 0 && consumer_quit
== 1) {
2445 /* poll on the array of fds */
2447 DBG("polling on %d fd", nb_fd
+ 1);
2448 num_rdy
= poll(pollfd
, nb_fd
+ 1, -1);
2449 DBG("poll num_rdy : %d", num_rdy
);
2450 if (num_rdy
== -1) {
2452 * Restart interrupted system call.
2454 if (errno
== EINTR
) {
2457 PERROR("Poll error");
2458 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_POLL_ERROR
);
2460 } else if (num_rdy
== 0) {
2461 DBG("Polling thread timed out");
2466 * If the consumer_data_pipe triggered poll go directly to the
2467 * beginning of the loop to update the array. We want to prioritize
2468 * array update over low-priority reads.
2470 if (pollfd
[nb_fd
].revents
& (POLLIN
| POLLPRI
)) {
2471 ssize_t pipe_readlen
;
2473 DBG("consumer_data_pipe wake up");
2474 pipe_readlen
= lttng_pipe_read(ctx
->consumer_data_pipe
,
2475 &new_stream
, sizeof(new_stream
));
2476 if (pipe_readlen
< 0) {
2477 ERR("Consumer data pipe ret %zd", pipe_readlen
);
2478 /* Continue so we can at least handle the current stream(s). */
2483 * If the stream is NULL, just ignore it. It's also possible that
2484 * the sessiond poll thread changed the consumer_quit state and is
2485 * waking us up to test it.
2487 if (new_stream
== NULL
) {
2488 validate_endpoint_status_data_stream();
2492 /* Continue to update the local streams and handle prio ones */
2496 /* Take care of high priority channels first. */
2497 for (i
= 0; i
< nb_fd
; i
++) {
2498 if (local_stream
[i
] == NULL
) {
2501 if (pollfd
[i
].revents
& POLLPRI
) {
2502 DBG("Urgent read on fd %d", pollfd
[i
].fd
);
2504 len
= ctx
->on_buffer_ready(local_stream
[i
], ctx
);
2505 /* it's ok to have an unavailable sub-buffer */
2506 if (len
< 0 && len
!= -EAGAIN
&& len
!= -ENODATA
) {
2507 /* Clean the stream and free it. */
2508 consumer_del_stream(local_stream
[i
], data_ht
);
2509 local_stream
[i
] = NULL
;
2510 } else if (len
> 0) {
2511 local_stream
[i
]->data_read
= 1;
2517 * If we read high prio channel in this loop, try again
2518 * for more high prio data.
2524 /* Take care of low priority channels. */
2525 for (i
= 0; i
< nb_fd
; i
++) {
2526 if (local_stream
[i
] == NULL
) {
2529 if ((pollfd
[i
].revents
& POLLIN
) ||
2530 local_stream
[i
]->hangup_flush_done
) {
2531 DBG("Normal read on fd %d", pollfd
[i
].fd
);
2532 len
= ctx
->on_buffer_ready(local_stream
[i
], ctx
);
2533 /* it's ok to have an unavailable sub-buffer */
2534 if (len
< 0 && len
!= -EAGAIN
&& len
!= -ENODATA
) {
2535 /* Clean the stream and free it. */
2536 consumer_del_stream(local_stream
[i
], data_ht
);
2537 local_stream
[i
] = NULL
;
2538 } else if (len
> 0) {
2539 local_stream
[i
]->data_read
= 1;
2544 /* Handle hangup and errors */
2545 for (i
= 0; i
< nb_fd
; i
++) {
2546 if (local_stream
[i
] == NULL
) {
2549 if (!local_stream
[i
]->hangup_flush_done
2550 && (pollfd
[i
].revents
& (POLLHUP
| POLLERR
| POLLNVAL
))
2551 && (consumer_data
.type
== LTTNG_CONSUMER32_UST
2552 || consumer_data
.type
== LTTNG_CONSUMER64_UST
)) {
2553 DBG("fd %d is hup|err|nval. Attempting flush and read.",
2555 lttng_ustconsumer_on_stream_hangup(local_stream
[i
]);
2556 /* Attempt read again, for the data we just flushed. */
2557 local_stream
[i
]->data_read
= 1;
2560 * If the poll flag is HUP/ERR/NVAL and we have
2561 * read no data in this pass, we can remove the
2562 * stream from its hash table.
2564 if ((pollfd
[i
].revents
& POLLHUP
)) {
2565 DBG("Polling fd %d tells it has hung up.", pollfd
[i
].fd
);
2566 if (!local_stream
[i
]->data_read
) {
2567 consumer_del_stream(local_stream
[i
], data_ht
);
2568 local_stream
[i
] = NULL
;
2571 } else if (pollfd
[i
].revents
& POLLERR
) {
2572 ERR("Error returned in polling fd %d.", pollfd
[i
].fd
);
2573 if (!local_stream
[i
]->data_read
) {
2574 consumer_del_stream(local_stream
[i
], data_ht
);
2575 local_stream
[i
] = NULL
;
2578 } else if (pollfd
[i
].revents
& POLLNVAL
) {
2579 ERR("Polling fd %d tells fd is not open.", pollfd
[i
].fd
);
2580 if (!local_stream
[i
]->data_read
) {
2581 consumer_del_stream(local_stream
[i
], data_ht
);
2582 local_stream
[i
] = NULL
;
2586 if (local_stream
[i
] != NULL
) {
2587 local_stream
[i
]->data_read
= 0;
2592 DBG("polling thread exiting");
2597 * Close the write side of the pipe so epoll_wait() in
2598 * consumer_thread_metadata_poll can catch it. The thread is monitoring the
2599 * read side of the pipe. If we close them both, epoll_wait strangely does
2600 * not return and could create a endless wait period if the pipe is the
2601 * only tracked fd in the poll set. The thread will take care of closing
2604 (void) lttng_pipe_write_close(ctx
->consumer_metadata_pipe
);
2606 destroy_data_stream_ht(data_ht
);
2608 rcu_unregister_thread();
2613 * Close wake-up end of each stream belonging to the channel. This will
2614 * allow the poll() on the stream read-side to detect when the
2615 * write-side (application) finally closes them.
2618 void consumer_close_channel_streams(struct lttng_consumer_channel
*channel
)
2620 struct lttng_ht
*ht
;
2621 struct lttng_consumer_stream
*stream
;
2622 struct lttng_ht_iter iter
;
2624 ht
= consumer_data
.stream_per_chan_id_ht
;
2627 cds_lfht_for_each_entry_duplicate(ht
->ht
,
2628 ht
->hash_fct(&channel
->key
, lttng_ht_seed
),
2629 ht
->match_fct
, &channel
->key
,
2630 &iter
.iter
, stream
, node_channel_id
.node
) {
2632 * Protect against teardown with mutex.
2634 pthread_mutex_lock(&stream
->lock
);
2635 if (cds_lfht_is_node_deleted(&stream
->node
.node
)) {
2638 switch (consumer_data
.type
) {
2639 case LTTNG_CONSUMER_KERNEL
:
2641 case LTTNG_CONSUMER32_UST
:
2642 case LTTNG_CONSUMER64_UST
:
2644 * Note: a mutex is taken internally within
2645 * liblttng-ust-ctl to protect timer wakeup_fd
2646 * use from concurrent close.
2648 lttng_ustconsumer_close_stream_wakeup(stream
);
2651 ERR("Unknown consumer_data type");
2655 pthread_mutex_unlock(&stream
->lock
);
2660 static void destroy_channel_ht(struct lttng_ht
*ht
)
2662 struct lttng_ht_iter iter
;
2663 struct lttng_consumer_channel
*channel
;
2671 cds_lfht_for_each_entry(ht
->ht
, &iter
.iter
, channel
, wait_fd_node
.node
) {
2672 ret
= lttng_ht_del(ht
, &iter
);
2677 lttng_ht_destroy(ht
);
2681 * This thread polls the channel fds to detect when they are being
2682 * closed. It closes all related streams if the channel is detected as
2683 * closed. It is currently only used as a shim layer for UST because the
2684 * consumerd needs to keep the per-stream wakeup end of pipes open for
2687 void *consumer_thread_channel_poll(void *data
)
2690 uint32_t revents
, nb_fd
;
2691 struct lttng_consumer_channel
*chan
= NULL
;
2692 struct lttng_ht_iter iter
;
2693 struct lttng_ht_node_u64
*node
;
2694 struct lttng_poll_event events
;
2695 struct lttng_consumer_local_data
*ctx
= data
;
2696 struct lttng_ht
*channel_ht
;
2698 rcu_register_thread();
2700 channel_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
2702 /* ENOMEM at this point. Better to bail out. */
2706 DBG("Thread channel poll started");
2708 /* Size is set to 1 for the consumer_channel pipe */
2709 ret
= lttng_poll_create(&events
, 2, LTTNG_CLOEXEC
);
2711 ERR("Poll set creation failed");
2715 ret
= lttng_poll_add(&events
, ctx
->consumer_channel_pipe
[0], LPOLLIN
);
2721 DBG("Channel main loop started");
2724 /* Only the channel pipe is set */
2725 if (LTTNG_POLL_GETNB(&events
) == 0 && consumer_quit
== 1) {
2730 DBG("Channel poll wait with %d fd(s)", LTTNG_POLL_GETNB(&events
));
2731 ret
= lttng_poll_wait(&events
, -1);
2732 DBG("Channel event catched in thread");
2734 if (errno
== EINTR
) {
2735 ERR("Poll EINTR catched");
2743 /* From here, the event is a channel wait fd */
2744 for (i
= 0; i
< nb_fd
; i
++) {
2745 revents
= LTTNG_POLL_GETEV(&events
, i
);
2746 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2748 /* Just don't waste time if no returned events for the fd */
2752 if (pollfd
== ctx
->consumer_channel_pipe
[0]) {
2753 if (revents
& (LPOLLERR
| LPOLLHUP
)) {
2754 DBG("Channel thread pipe hung up");
2756 * Remove the pipe from the poll set and continue the loop
2757 * since their might be data to consume.
2759 lttng_poll_del(&events
, ctx
->consumer_channel_pipe
[0]);
2761 } else if (revents
& LPOLLIN
) {
2762 enum consumer_channel_action action
;
2765 ret
= read_channel_pipe(ctx
, &chan
, &key
, &action
);
2767 ERR("Error reading channel pipe");
2772 case CONSUMER_CHANNEL_ADD
:
2773 DBG("Adding channel %d to poll set",
2776 lttng_ht_node_init_u64(&chan
->wait_fd_node
,
2779 lttng_ht_add_unique_u64(channel_ht
,
2780 &chan
->wait_fd_node
);
2782 /* Add channel to the global poll events list */
2783 lttng_poll_add(&events
, chan
->wait_fd
,
2784 LPOLLIN
| LPOLLPRI
);
2786 case CONSUMER_CHANNEL_DEL
:
2788 struct lttng_consumer_stream
*stream
, *stmp
;
2791 chan
= consumer_find_channel(key
);
2794 ERR("UST consumer get channel key %" PRIu64
" not found for del channel", key
);
2797 lttng_poll_del(&events
, chan
->wait_fd
);
2798 iter
.iter
.node
= &chan
->wait_fd_node
.node
;
2799 ret
= lttng_ht_del(channel_ht
, &iter
);
2801 consumer_close_channel_streams(chan
);
2803 switch (consumer_data
.type
) {
2804 case LTTNG_CONSUMER_KERNEL
:
2806 case LTTNG_CONSUMER32_UST
:
2807 case LTTNG_CONSUMER64_UST
:
2808 /* Delete streams that might have been left in the stream list. */
2809 cds_list_for_each_entry_safe(stream
, stmp
, &chan
->streams
.head
,
2811 cds_list_del(&stream
->send_node
);
2812 lttng_ustconsumer_del_stream(stream
);
2813 uatomic_sub(&stream
->chan
->refcount
, 1);
2814 assert(&chan
->refcount
);
2819 ERR("Unknown consumer_data type");
2824 * Release our own refcount. Force channel deletion even if
2825 * streams were not initialized.
2827 if (!uatomic_sub_return(&chan
->refcount
, 1)) {
2828 consumer_del_channel(chan
);
2833 case CONSUMER_CHANNEL_QUIT
:
2835 * Remove the pipe from the poll set and continue the loop
2836 * since their might be data to consume.
2838 lttng_poll_del(&events
, ctx
->consumer_channel_pipe
[0]);
2841 ERR("Unknown action");
2846 /* Handle other stream */
2852 uint64_t tmp_id
= (uint64_t) pollfd
;
2854 lttng_ht_lookup(channel_ht
, &tmp_id
, &iter
);
2856 node
= lttng_ht_iter_get_node_u64(&iter
);
2859 chan
= caa_container_of(node
, struct lttng_consumer_channel
,
2862 /* Check for error event */
2863 if (revents
& (LPOLLERR
| LPOLLHUP
)) {
2864 DBG("Channel fd %d is hup|err.", pollfd
);
2866 lttng_poll_del(&events
, chan
->wait_fd
);
2867 ret
= lttng_ht_del(channel_ht
, &iter
);
2869 consumer_close_channel_streams(chan
);
2871 /* Release our own refcount */
2872 if (!uatomic_sub_return(&chan
->refcount
, 1)
2873 && !uatomic_read(&chan
->nb_init_stream_left
)) {
2874 consumer_del_channel(chan
);
2878 /* Release RCU lock for the channel looked up */
2884 lttng_poll_clean(&events
);
2886 destroy_channel_ht(channel_ht
);
2888 DBG("Channel poll thread exiting");
2889 rcu_unregister_thread();
2893 static int set_metadata_socket(struct lttng_consumer_local_data
*ctx
,
2894 struct pollfd
*sockpoll
, int client_socket
)
2901 if (lttng_consumer_poll_socket(sockpoll
) < 0) {
2905 DBG("Metadata connection on client_socket");
2907 /* Blocking call, waiting for transmission */
2908 ctx
->consumer_metadata_socket
= lttcomm_accept_unix_sock(client_socket
);
2909 if (ctx
->consumer_metadata_socket
< 0) {
2910 WARN("On accept metadata");
2921 * This thread listens on the consumerd socket and receives the file
2922 * descriptors from the session daemon.
2924 void *consumer_thread_sessiond_poll(void *data
)
2926 int sock
= -1, client_socket
, ret
;
2928 * structure to poll for incoming data on communication socket avoids
2929 * making blocking sockets.
2931 struct pollfd consumer_sockpoll
[2];
2932 struct lttng_consumer_local_data
*ctx
= data
;
2934 rcu_register_thread();
2936 DBG("Creating command socket %s", ctx
->consumer_command_sock_path
);
2937 unlink(ctx
->consumer_command_sock_path
);
2938 client_socket
= lttcomm_create_unix_sock(ctx
->consumer_command_sock_path
);
2939 if (client_socket
< 0) {
2940 ERR("Cannot create command socket");
2944 ret
= lttcomm_listen_unix_sock(client_socket
);
2949 DBG("Sending ready command to lttng-sessiond");
2950 ret
= lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_COMMAND_SOCK_READY
);
2951 /* return < 0 on error, but == 0 is not fatal */
2953 ERR("Error sending ready command to lttng-sessiond");
2957 /* prepare the FDs to poll : to client socket and the should_quit pipe */
2958 consumer_sockpoll
[0].fd
= ctx
->consumer_should_quit
[0];
2959 consumer_sockpoll
[0].events
= POLLIN
| POLLPRI
;
2960 consumer_sockpoll
[1].fd
= client_socket
;
2961 consumer_sockpoll
[1].events
= POLLIN
| POLLPRI
;
2963 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
2966 DBG("Connection on client_socket");
2968 /* Blocking call, waiting for transmission */
2969 sock
= lttcomm_accept_unix_sock(client_socket
);
2976 * Setup metadata socket which is the second socket connection on the
2977 * command unix socket.
2979 ret
= set_metadata_socket(ctx
, consumer_sockpoll
, client_socket
);
2984 /* This socket is not useful anymore. */
2985 ret
= close(client_socket
);
2987 PERROR("close client_socket");
2991 /* update the polling structure to poll on the established socket */
2992 consumer_sockpoll
[1].fd
= sock
;
2993 consumer_sockpoll
[1].events
= POLLIN
| POLLPRI
;
2996 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
2999 DBG("Incoming command on sock");
3000 ret
= lttng_consumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
3001 if (ret
== -ENOENT
) {
3002 DBG("Received STOP command");
3007 * This could simply be a session daemon quitting. Don't output
3010 DBG("Communication interrupted on command socket");
3013 if (consumer_quit
) {
3014 DBG("consumer_thread_receive_fds received quit from signal");
3017 DBG("received command on sock");
3020 DBG("Consumer thread sessiond poll exiting");
3023 * Close metadata streams since the producer is the session daemon which
3026 * NOTE: for now, this only applies to the UST tracer.
3028 lttng_consumer_close_metadata();
3031 * when all fds have hung up, the polling thread
3037 * Notify the data poll thread to poll back again and test the
3038 * consumer_quit state that we just set so to quit gracefully.
3040 notify_thread_lttng_pipe(ctx
->consumer_data_pipe
);
3042 notify_channel_pipe(ctx
, NULL
, -1, CONSUMER_CHANNEL_QUIT
);
3044 /* Cleaning up possibly open sockets. */
3048 PERROR("close sock sessiond poll");
3051 if (client_socket
>= 0) {
3052 ret
= close(client_socket
);
3054 PERROR("close client_socket sessiond poll");
3058 rcu_unregister_thread();
3062 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
3063 struct lttng_consumer_local_data
*ctx
)
3067 pthread_mutex_lock(&stream
->lock
);
3068 if (stream
->metadata_flag
) {
3069 pthread_mutex_lock(&stream
->metadata_rdv_lock
);
3072 switch (consumer_data
.type
) {
3073 case LTTNG_CONSUMER_KERNEL
:
3074 ret
= lttng_kconsumer_read_subbuffer(stream
, ctx
);
3076 case LTTNG_CONSUMER32_UST
:
3077 case LTTNG_CONSUMER64_UST
:
3078 ret
= lttng_ustconsumer_read_subbuffer(stream
, ctx
);
3081 ERR("Unknown consumer_data type");
3087 if (stream
->metadata_flag
) {
3088 pthread_cond_broadcast(&stream
->metadata_rdv
);
3089 pthread_mutex_unlock(&stream
->metadata_rdv_lock
);
3091 pthread_mutex_unlock(&stream
->lock
);
3095 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
3097 switch (consumer_data
.type
) {
3098 case LTTNG_CONSUMER_KERNEL
:
3099 return lttng_kconsumer_on_recv_stream(stream
);
3100 case LTTNG_CONSUMER32_UST
:
3101 case LTTNG_CONSUMER64_UST
:
3102 return lttng_ustconsumer_on_recv_stream(stream
);
3104 ERR("Unknown consumer_data type");
3111 * Allocate and set consumer data hash tables.
3113 void lttng_consumer_init(void)
3115 consumer_data
.channel_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
3116 consumer_data
.relayd_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
3117 consumer_data
.stream_list_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
3118 consumer_data
.stream_per_chan_id_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
3122 * Process the ADD_RELAYD command receive by a consumer.
3124 * This will create a relayd socket pair and add it to the relayd hash table.
3125 * The caller MUST acquire a RCU read side lock before calling it.
3127 int consumer_add_relayd_socket(uint64_t net_seq_idx
, int sock_type
,
3128 struct lttng_consumer_local_data
*ctx
, int sock
,
3129 struct pollfd
*consumer_sockpoll
,
3130 struct lttcomm_relayd_sock
*relayd_sock
, uint64_t sessiond_id
,
3131 uint64_t relayd_session_id
)
3133 int fd
= -1, ret
= -1, relayd_created
= 0;
3134 enum lttng_error_code ret_code
= LTTNG_OK
;
3135 struct consumer_relayd_sock_pair
*relayd
= NULL
;
3138 assert(relayd_sock
);
3140 DBG("Consumer adding relayd socket (idx: %" PRIu64
")", net_seq_idx
);
3142 /* Get relayd reference if exists. */
3143 relayd
= consumer_find_relayd(net_seq_idx
);
3144 if (relayd
== NULL
) {
3145 assert(sock_type
== LTTNG_STREAM_CONTROL
);
3146 /* Not found. Allocate one. */
3147 relayd
= consumer_allocate_relayd_sock_pair(net_seq_idx
);
3148 if (relayd
== NULL
) {
3150 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
3153 relayd
->sessiond_session_id
= sessiond_id
;
3158 * This code path MUST continue to the consumer send status message to
3159 * we can notify the session daemon and continue our work without
3160 * killing everything.
3164 * relayd key should never be found for control socket.
3166 assert(sock_type
!= LTTNG_STREAM_CONTROL
);
3169 /* First send a status message before receiving the fds. */
3170 ret
= consumer_send_status_msg(sock
, LTTNG_OK
);
3172 /* Somehow, the session daemon is not responding anymore. */
3173 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_FATAL
);
3174 goto error_nosignal
;
3177 /* Poll on consumer socket. */
3178 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
3179 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_POLL_ERROR
);
3181 goto error_nosignal
;
3184 /* Get relayd socket from session daemon */
3185 ret
= lttcomm_recv_fds_unix_sock(sock
, &fd
, 1);
3186 if (ret
!= sizeof(fd
)) {
3188 fd
= -1; /* Just in case it gets set with an invalid value. */
3191 * Failing to receive FDs might indicate a major problem such as
3192 * reaching a fd limit during the receive where the kernel returns a
3193 * MSG_CTRUNC and fails to cleanup the fd in the queue. Any case, we
3194 * don't take any chances and stop everything.
3196 * XXX: Feature request #558 will fix that and avoid this possible
3197 * issue when reaching the fd limit.
3199 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_FD
);
3200 ret_code
= LTTCOMM_CONSUMERD_ERROR_RECV_FD
;
3204 /* Copy socket information and received FD */
3205 switch (sock_type
) {
3206 case LTTNG_STREAM_CONTROL
:
3207 /* Copy received lttcomm socket */
3208 lttcomm_copy_sock(&relayd
->control_sock
.sock
, &relayd_sock
->sock
);
3209 ret
= lttcomm_create_sock(&relayd
->control_sock
.sock
);
3210 /* Handle create_sock error. */
3212 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
3216 * Close the socket created internally by
3217 * lttcomm_create_sock, so we can replace it by the one
3218 * received from sessiond.
3220 if (close(relayd
->control_sock
.sock
.fd
)) {
3224 /* Assign new file descriptor */
3225 relayd
->control_sock
.sock
.fd
= fd
;
3226 fd
= -1; /* For error path */
3227 /* Assign version values. */
3228 relayd
->control_sock
.major
= relayd_sock
->major
;
3229 relayd
->control_sock
.minor
= relayd_sock
->minor
;
3231 relayd
->relayd_session_id
= relayd_session_id
;
3234 case LTTNG_STREAM_DATA
:
3235 /* Copy received lttcomm socket */
3236 lttcomm_copy_sock(&relayd
->data_sock
.sock
, &relayd_sock
->sock
);
3237 ret
= lttcomm_create_sock(&relayd
->data_sock
.sock
);
3238 /* Handle create_sock error. */
3240 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
3244 * Close the socket created internally by
3245 * lttcomm_create_sock, so we can replace it by the one
3246 * received from sessiond.
3248 if (close(relayd
->data_sock
.sock
.fd
)) {
3252 /* Assign new file descriptor */
3253 relayd
->data_sock
.sock
.fd
= fd
;
3254 fd
= -1; /* for eventual error paths */
3255 /* Assign version values. */
3256 relayd
->data_sock
.major
= relayd_sock
->major
;
3257 relayd
->data_sock
.minor
= relayd_sock
->minor
;
3260 ERR("Unknown relayd socket type (%d)", sock_type
);
3262 ret_code
= LTTCOMM_CONSUMERD_FATAL
;
3266 DBG("Consumer %s socket created successfully with net idx %" PRIu64
" (fd: %d)",
3267 sock_type
== LTTNG_STREAM_CONTROL
? "control" : "data",
3268 relayd
->net_seq_idx
, fd
);
3270 /* We successfully added the socket. Send status back. */
3271 ret
= consumer_send_status_msg(sock
, ret_code
);
3273 /* Somehow, the session daemon is not responding anymore. */
3274 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_FATAL
);
3275 goto error_nosignal
;
3279 * Add relayd socket pair to consumer data hashtable. If object already
3280 * exists or on error, the function gracefully returns.
3288 if (consumer_send_status_msg(sock
, ret_code
) < 0) {
3289 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_FATAL
);
3293 /* Close received socket if valid. */
3296 PERROR("close received socket");
3300 if (relayd_created
) {
3308 * Try to lock the stream mutex.
3310 * On success, 1 is returned else 0 indicating that the mutex is NOT lock.
3312 static int stream_try_lock(struct lttng_consumer_stream
*stream
)
3319 * Try to lock the stream mutex. On failure, we know that the stream is
3320 * being used else where hence there is data still being extracted.
3322 ret
= pthread_mutex_trylock(&stream
->lock
);
3324 /* For both EBUSY and EINVAL error, the mutex is NOT locked. */
3336 * Search for a relayd associated to the session id and return the reference.
3338 * A rcu read side lock MUST be acquire before calling this function and locked
3339 * until the relayd object is no longer necessary.
3341 static struct consumer_relayd_sock_pair
*find_relayd_by_session_id(uint64_t id
)
3343 struct lttng_ht_iter iter
;
3344 struct consumer_relayd_sock_pair
*relayd
= NULL
;
3346 /* Iterate over all relayd since they are indexed by net_seq_idx. */
3347 cds_lfht_for_each_entry(consumer_data
.relayd_ht
->ht
, &iter
.iter
, relayd
,
3350 * Check by sessiond id which is unique here where the relayd session
3351 * id might not be when having multiple relayd.
3353 if (relayd
->sessiond_session_id
== id
) {
3354 /* Found the relayd. There can be only one per id. */
3366 * Check if for a given session id there is still data needed to be extract
3369 * Return 1 if data is pending or else 0 meaning ready to be read.
3371 int consumer_data_pending(uint64_t id
)
3374 struct lttng_ht_iter iter
;
3375 struct lttng_ht
*ht
;
3376 struct lttng_consumer_stream
*stream
;
3377 struct consumer_relayd_sock_pair
*relayd
= NULL
;
3378 int (*data_pending
)(struct lttng_consumer_stream
*);
3380 DBG("Consumer data pending command on session id %" PRIu64
, id
);
3383 pthread_mutex_lock(&consumer_data
.lock
);
3385 switch (consumer_data
.type
) {
3386 case LTTNG_CONSUMER_KERNEL
:
3387 data_pending
= lttng_kconsumer_data_pending
;
3389 case LTTNG_CONSUMER32_UST
:
3390 case LTTNG_CONSUMER64_UST
:
3391 data_pending
= lttng_ustconsumer_data_pending
;
3394 ERR("Unknown consumer data type");
3398 /* Ease our life a bit */
3399 ht
= consumer_data
.stream_list_ht
;
3401 relayd
= find_relayd_by_session_id(id
);
3403 /* Send init command for data pending. */
3404 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
3405 ret
= relayd_begin_data_pending(&relayd
->control_sock
,
3406 relayd
->relayd_session_id
);
3407 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
3409 /* Communication error thus the relayd so no data pending. */
3410 goto data_not_pending
;
3414 cds_lfht_for_each_entry_duplicate(ht
->ht
,
3415 ht
->hash_fct(&id
, lttng_ht_seed
),
3417 &iter
.iter
, stream
, node_session_id
.node
) {
3418 /* If this call fails, the stream is being used hence data pending. */
3419 ret
= stream_try_lock(stream
);
3425 * A removed node from the hash table indicates that the stream has
3426 * been deleted thus having a guarantee that the buffers are closed
3427 * on the consumer side. However, data can still be transmitted
3428 * over the network so don't skip the relayd check.
3430 ret
= cds_lfht_is_node_deleted(&stream
->node
.node
);
3433 * An empty output file is not valid. We need at least one packet
3434 * generated per stream, even if it contains no event, so it
3435 * contains at least one packet header.
3437 if (stream
->output_written
== 0) {
3438 pthread_mutex_unlock(&stream
->lock
);
3441 /* Check the stream if there is data in the buffers. */
3442 ret
= data_pending(stream
);
3444 pthread_mutex_unlock(&stream
->lock
);
3451 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
3452 if (stream
->metadata_flag
) {
3453 ret
= relayd_quiescent_control(&relayd
->control_sock
,
3454 stream
->relayd_stream_id
);
3456 ret
= relayd_data_pending(&relayd
->control_sock
,
3457 stream
->relayd_stream_id
,
3458 stream
->next_net_seq_num
- 1);
3460 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
3462 pthread_mutex_unlock(&stream
->lock
);
3466 pthread_mutex_unlock(&stream
->lock
);
3470 unsigned int is_data_inflight
= 0;
3472 /* Send init command for data pending. */
3473 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
3474 ret
= relayd_end_data_pending(&relayd
->control_sock
,
3475 relayd
->relayd_session_id
, &is_data_inflight
);
3476 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
3478 goto data_not_pending
;
3480 if (is_data_inflight
) {
3486 * Finding _no_ node in the hash table and no inflight data means that the
3487 * stream(s) have been removed thus data is guaranteed to be available for
3488 * analysis from the trace files.
3492 /* Data is available to be read by a viewer. */
3493 pthread_mutex_unlock(&consumer_data
.lock
);
3498 /* Data is still being extracted from buffers. */
3499 pthread_mutex_unlock(&consumer_data
.lock
);
3505 * Send a ret code status message to the sessiond daemon.
3507 * Return the sendmsg() return value.
3509 int consumer_send_status_msg(int sock
, int ret_code
)
3511 struct lttcomm_consumer_status_msg msg
;
3513 msg
.ret_code
= ret_code
;
3515 return lttcomm_send_unix_sock(sock
, &msg
, sizeof(msg
));
3519 * Send a channel status message to the sessiond daemon.
3521 * Return the sendmsg() return value.
3523 int consumer_send_status_channel(int sock
,
3524 struct lttng_consumer_channel
*channel
)
3526 struct lttcomm_consumer_status_channel msg
;
3531 msg
.ret_code
= -LTTNG_ERR_UST_CHAN_FAIL
;
3533 msg
.ret_code
= LTTNG_OK
;
3534 msg
.key
= channel
->key
;
3535 msg
.stream_count
= channel
->streams
.count
;
3538 return lttcomm_send_unix_sock(sock
, &msg
, sizeof(msg
));
3542 * Using a maximum stream size with the produced and consumed position of a
3543 * stream, computes the new consumed position to be as close as possible to the
3544 * maximum possible stream size.
3546 * If maximum stream size is lower than the possible buffer size (produced -
3547 * consumed), the consumed_pos given is returned untouched else the new value
3550 unsigned long consumer_get_consumed_maxsize(unsigned long consumed_pos
,
3551 unsigned long produced_pos
, uint64_t max_stream_size
)
3553 if (max_stream_size
&& max_stream_size
< (produced_pos
- consumed_pos
)) {
3554 /* Offset from the produced position to get the latest buffers. */
3555 return produced_pos
- max_stream_size
;
3558 return consumed_pos
;