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 <bin/lttng-consumerd/health-consumerd.h>
34 #include <common/common.h>
35 #include <common/utils.h>
36 #include <common/compat/poll.h>
37 #include <common/index/index.h>
38 #include <common/kernel-ctl/kernel-ctl.h>
39 #include <common/sessiond-comm/relayd.h>
40 #include <common/sessiond-comm/sessiond-comm.h>
41 #include <common/kernel-consumer/kernel-consumer.h>
42 #include <common/relayd/relayd.h>
43 #include <common/ust-consumer/ust-consumer.h>
44 #include <common/consumer-timer.h>
47 #include "consumer-stream.h"
49 struct lttng_consumer_global_data consumer_data
= {
52 .type
= LTTNG_CONSUMER_UNKNOWN
,
55 enum consumer_channel_action
{
58 CONSUMER_CHANNEL_QUIT
,
61 struct consumer_channel_msg
{
62 enum consumer_channel_action action
;
63 struct lttng_consumer_channel
*chan
; /* add */
64 uint64_t key
; /* del */
68 * Flag to inform the polling thread to quit when all fd hung up. Updated by
69 * the consumer_thread_receive_fds when it notices that all fds has hung up.
70 * Also updated by the signal handler (consumer_should_exit()). Read by the
73 volatile int consumer_quit
;
76 * Global hash table containing respectively metadata and data streams. The
77 * stream element in this ht should only be updated by the metadata poll thread
78 * for the metadata and the data poll thread for the data.
80 static struct lttng_ht
*metadata_ht
;
81 static struct lttng_ht
*data_ht
;
84 * Notify a thread lttng pipe to poll back again. This usually means that some
85 * global state has changed so we just send back the thread in a poll wait
88 static void notify_thread_lttng_pipe(struct lttng_pipe
*pipe
)
90 struct lttng_consumer_stream
*null_stream
= NULL
;
94 (void) lttng_pipe_write(pipe
, &null_stream
, sizeof(null_stream
));
97 static void notify_health_quit_pipe(int *pipe
)
101 ret
= lttng_write(pipe
[1], "4", 1);
103 PERROR("write consumer health quit");
107 static void notify_channel_pipe(struct lttng_consumer_local_data
*ctx
,
108 struct lttng_consumer_channel
*chan
,
110 enum consumer_channel_action action
)
112 struct consumer_channel_msg msg
;
115 memset(&msg
, 0, sizeof(msg
));
120 ret
= lttng_write(ctx
->consumer_channel_pipe
[1], &msg
, sizeof(msg
));
121 if (ret
< sizeof(msg
)) {
122 PERROR("notify_channel_pipe write error");
126 void notify_thread_del_channel(struct lttng_consumer_local_data
*ctx
,
129 notify_channel_pipe(ctx
, NULL
, key
, CONSUMER_CHANNEL_DEL
);
132 static int read_channel_pipe(struct lttng_consumer_local_data
*ctx
,
133 struct lttng_consumer_channel
**chan
,
135 enum consumer_channel_action
*action
)
137 struct consumer_channel_msg msg
;
140 ret
= lttng_read(ctx
->consumer_channel_pipe
[0], &msg
, sizeof(msg
));
141 if (ret
< sizeof(msg
)) {
145 *action
= msg
.action
;
153 * Find a stream. The consumer_data.lock must be locked during this
156 static struct lttng_consumer_stream
*find_stream(uint64_t key
,
159 struct lttng_ht_iter iter
;
160 struct lttng_ht_node_u64
*node
;
161 struct lttng_consumer_stream
*stream
= NULL
;
165 /* -1ULL keys are lookup failures */
166 if (key
== (uint64_t) -1ULL) {
172 lttng_ht_lookup(ht
, &key
, &iter
);
173 node
= lttng_ht_iter_get_node_u64(&iter
);
175 stream
= caa_container_of(node
, struct lttng_consumer_stream
, node
);
183 static void steal_stream_key(uint64_t key
, struct lttng_ht
*ht
)
185 struct lttng_consumer_stream
*stream
;
188 stream
= find_stream(key
, ht
);
190 stream
->key
= (uint64_t) -1ULL;
192 * We don't want the lookup to match, but we still need
193 * to iterate on this stream when iterating over the hash table. Just
194 * change the node key.
196 stream
->node
.key
= (uint64_t) -1ULL;
202 * Return a channel object for the given key.
204 * RCU read side lock MUST be acquired before calling this function and
205 * protects the channel ptr.
207 struct lttng_consumer_channel
*consumer_find_channel(uint64_t key
)
209 struct lttng_ht_iter iter
;
210 struct lttng_ht_node_u64
*node
;
211 struct lttng_consumer_channel
*channel
= NULL
;
213 /* -1ULL keys are lookup failures */
214 if (key
== (uint64_t) -1ULL) {
218 lttng_ht_lookup(consumer_data
.channel_ht
, &key
, &iter
);
219 node
= lttng_ht_iter_get_node_u64(&iter
);
221 channel
= caa_container_of(node
, struct lttng_consumer_channel
, node
);
227 static void free_stream_rcu(struct rcu_head
*head
)
229 struct lttng_ht_node_u64
*node
=
230 caa_container_of(head
, struct lttng_ht_node_u64
, head
);
231 struct lttng_consumer_stream
*stream
=
232 caa_container_of(node
, struct lttng_consumer_stream
, node
);
237 static void free_channel_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 lttng_consumer_channel
*channel
=
242 caa_container_of(node
, struct lttng_consumer_channel
, node
);
248 * RCU protected relayd socket pair free.
250 static void free_relayd_rcu(struct rcu_head
*head
)
252 struct lttng_ht_node_u64
*node
=
253 caa_container_of(head
, struct lttng_ht_node_u64
, head
);
254 struct consumer_relayd_sock_pair
*relayd
=
255 caa_container_of(node
, struct consumer_relayd_sock_pair
, node
);
258 * Close all sockets. This is done in the call RCU since we don't want the
259 * socket fds to be reassigned thus potentially creating bad state of the
262 * We do not have to lock the control socket mutex here since at this stage
263 * there is no one referencing to this relayd object.
265 (void) relayd_close(&relayd
->control_sock
);
266 (void) relayd_close(&relayd
->data_sock
);
272 * Destroy and free relayd socket pair object.
274 void consumer_destroy_relayd(struct consumer_relayd_sock_pair
*relayd
)
277 struct lttng_ht_iter iter
;
279 if (relayd
== NULL
) {
283 DBG("Consumer destroy and close relayd socket pair");
285 iter
.iter
.node
= &relayd
->node
.node
;
286 ret
= lttng_ht_del(consumer_data
.relayd_ht
, &iter
);
288 /* We assume the relayd is being or is destroyed */
292 /* RCU free() call */
293 call_rcu(&relayd
->node
.head
, free_relayd_rcu
);
297 * Remove a channel from the global list protected by a mutex. This function is
298 * also responsible for freeing its data structures.
300 void consumer_del_channel(struct lttng_consumer_channel
*channel
)
303 struct lttng_ht_iter iter
;
304 struct lttng_consumer_stream
*stream
, *stmp
;
306 DBG("Consumer delete channel key %" PRIu64
, channel
->key
);
308 pthread_mutex_lock(&consumer_data
.lock
);
309 pthread_mutex_lock(&channel
->lock
);
311 /* Delete streams that might have been left in the stream list. */
312 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
314 cds_list_del(&stream
->send_node
);
316 * Once a stream is added to this list, the buffers were created so
317 * we have a guarantee that this call will succeed.
319 consumer_stream_destroy(stream
, NULL
);
322 if (channel
->live_timer_enabled
== 1) {
323 consumer_timer_live_stop(channel
);
326 switch (consumer_data
.type
) {
327 case LTTNG_CONSUMER_KERNEL
:
329 case LTTNG_CONSUMER32_UST
:
330 case LTTNG_CONSUMER64_UST
:
331 lttng_ustconsumer_del_channel(channel
);
334 ERR("Unknown consumer_data type");
340 iter
.iter
.node
= &channel
->node
.node
;
341 ret
= lttng_ht_del(consumer_data
.channel_ht
, &iter
);
345 call_rcu(&channel
->node
.head
, free_channel_rcu
);
347 pthread_mutex_unlock(&channel
->lock
);
348 pthread_mutex_unlock(&consumer_data
.lock
);
352 * Iterate over the relayd hash table and destroy each element. Finally,
353 * destroy the whole hash table.
355 static void cleanup_relayd_ht(void)
357 struct lttng_ht_iter iter
;
358 struct consumer_relayd_sock_pair
*relayd
;
362 cds_lfht_for_each_entry(consumer_data
.relayd_ht
->ht
, &iter
.iter
, relayd
,
364 consumer_destroy_relayd(relayd
);
369 lttng_ht_destroy(consumer_data
.relayd_ht
);
373 * Update the end point status of all streams having the given network sequence
374 * index (relayd index).
376 * It's atomically set without having the stream mutex locked which is fine
377 * because we handle the write/read race with a pipe wakeup for each thread.
379 static void update_endpoint_status_by_netidx(uint64_t net_seq_idx
,
380 enum consumer_endpoint_status status
)
382 struct lttng_ht_iter iter
;
383 struct lttng_consumer_stream
*stream
;
385 DBG("Consumer set delete flag on stream by idx %" PRIu64
, net_seq_idx
);
389 /* Let's begin with metadata */
390 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
, node
.node
) {
391 if (stream
->net_seq_idx
== net_seq_idx
) {
392 uatomic_set(&stream
->endpoint_status
, status
);
393 DBG("Delete flag set to metadata stream %d", stream
->wait_fd
);
397 /* Follow up by the data streams */
398 cds_lfht_for_each_entry(data_ht
->ht
, &iter
.iter
, stream
, node
.node
) {
399 if (stream
->net_seq_idx
== net_seq_idx
) {
400 uatomic_set(&stream
->endpoint_status
, status
);
401 DBG("Delete flag set to data stream %d", stream
->wait_fd
);
408 * Cleanup a relayd object by flagging every associated streams for deletion,
409 * destroying the object meaning removing it from the relayd hash table,
410 * closing the sockets and freeing the memory in a RCU call.
412 * If a local data context is available, notify the threads that the streams'
413 * state have changed.
415 static void cleanup_relayd(struct consumer_relayd_sock_pair
*relayd
,
416 struct lttng_consumer_local_data
*ctx
)
422 DBG("Cleaning up relayd sockets");
424 /* Save the net sequence index before destroying the object */
425 netidx
= relayd
->net_seq_idx
;
428 * Delete the relayd from the relayd hash table, close the sockets and free
429 * the object in a RCU call.
431 consumer_destroy_relayd(relayd
);
433 /* Set inactive endpoint to all streams */
434 update_endpoint_status_by_netidx(netidx
, CONSUMER_ENDPOINT_INACTIVE
);
437 * With a local data context, notify the threads that the streams' state
438 * have changed. The write() action on the pipe acts as an "implicit"
439 * memory barrier ordering the updates of the end point status from the
440 * read of this status which happens AFTER receiving this notify.
443 notify_thread_lttng_pipe(ctx
->consumer_data_pipe
);
444 notify_thread_lttng_pipe(ctx
->consumer_metadata_pipe
);
449 * Flag a relayd socket pair for destruction. Destroy it if the refcount
452 * RCU read side lock MUST be aquired before calling this function.
454 void consumer_flag_relayd_for_destroy(struct consumer_relayd_sock_pair
*relayd
)
458 /* Set destroy flag for this object */
459 uatomic_set(&relayd
->destroy_flag
, 1);
461 /* Destroy the relayd if refcount is 0 */
462 if (uatomic_read(&relayd
->refcount
) == 0) {
463 consumer_destroy_relayd(relayd
);
468 * Completly destroy stream from every visiable data structure and the given
471 * One this call returns, the stream object is not longer usable nor visible.
473 void consumer_del_stream(struct lttng_consumer_stream
*stream
,
476 consumer_stream_destroy(stream
, ht
);
480 * XXX naming of del vs destroy is all mixed up.
482 void consumer_del_stream_for_data(struct lttng_consumer_stream
*stream
)
484 consumer_stream_destroy(stream
, data_ht
);
487 void consumer_del_stream_for_metadata(struct lttng_consumer_stream
*stream
)
489 consumer_stream_destroy(stream
, metadata_ht
);
492 struct lttng_consumer_stream
*consumer_allocate_stream(uint64_t channel_key
,
494 enum lttng_consumer_stream_state state
,
495 const char *channel_name
,
502 enum consumer_channel_type type
,
503 unsigned int monitor
)
506 struct lttng_consumer_stream
*stream
;
508 stream
= zmalloc(sizeof(*stream
));
509 if (stream
== NULL
) {
510 PERROR("malloc struct lttng_consumer_stream");
517 stream
->key
= stream_key
;
519 stream
->out_fd_offset
= 0;
520 stream
->output_written
= 0;
521 stream
->state
= state
;
524 stream
->net_seq_idx
= relayd_id
;
525 stream
->session_id
= session_id
;
526 stream
->monitor
= monitor
;
527 stream
->endpoint_status
= CONSUMER_ENDPOINT_ACTIVE
;
528 stream
->index_fd
= -1;
529 pthread_mutex_init(&stream
->lock
, NULL
);
531 /* If channel is the metadata, flag this stream as metadata. */
532 if (type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
533 stream
->metadata_flag
= 1;
534 /* Metadata is flat out. */
535 strncpy(stream
->name
, DEFAULT_METADATA_NAME
, sizeof(stream
->name
));
536 /* Live rendez-vous point. */
537 pthread_cond_init(&stream
->metadata_rdv
, NULL
);
538 pthread_mutex_init(&stream
->metadata_rdv_lock
, NULL
);
540 /* Format stream name to <channel_name>_<cpu_number> */
541 ret
= snprintf(stream
->name
, sizeof(stream
->name
), "%s_%d",
544 PERROR("snprintf stream name");
549 /* Key is always the wait_fd for streams. */
550 lttng_ht_node_init_u64(&stream
->node
, stream
->key
);
552 /* Init node per channel id key */
553 lttng_ht_node_init_u64(&stream
->node_channel_id
, channel_key
);
555 /* Init session id node with the stream session id */
556 lttng_ht_node_init_u64(&stream
->node_session_id
, stream
->session_id
);
558 DBG3("Allocated stream %s (key %" PRIu64
", chan_key %" PRIu64
559 " relayd_id %" PRIu64
", session_id %" PRIu64
,
560 stream
->name
, stream
->key
, channel_key
,
561 stream
->net_seq_idx
, stream
->session_id
);
577 * Add a stream to the global list protected by a mutex.
579 int consumer_add_data_stream(struct lttng_consumer_stream
*stream
)
581 struct lttng_ht
*ht
= data_ht
;
587 DBG3("Adding consumer stream %" PRIu64
, stream
->key
);
589 pthread_mutex_lock(&consumer_data
.lock
);
590 pthread_mutex_lock(&stream
->chan
->lock
);
591 pthread_mutex_lock(&stream
->chan
->timer_lock
);
592 pthread_mutex_lock(&stream
->lock
);
595 /* Steal stream identifier to avoid having streams with the same key */
596 steal_stream_key(stream
->key
, ht
);
598 lttng_ht_add_unique_u64(ht
, &stream
->node
);
600 lttng_ht_add_u64(consumer_data
.stream_per_chan_id_ht
,
601 &stream
->node_channel_id
);
604 * Add stream to the stream_list_ht of the consumer data. No need to steal
605 * the key since the HT does not use it and we allow to add redundant keys
608 lttng_ht_add_u64(consumer_data
.stream_list_ht
, &stream
->node_session_id
);
611 * When nb_init_stream_left reaches 0, we don't need to trigger any action
612 * in terms of destroying the associated channel, because the action that
613 * causes the count to become 0 also causes a stream to be added. The
614 * channel deletion will thus be triggered by the following removal of this
617 if (uatomic_read(&stream
->chan
->nb_init_stream_left
) > 0) {
618 /* Increment refcount before decrementing nb_init_stream_left */
620 uatomic_dec(&stream
->chan
->nb_init_stream_left
);
623 /* Update consumer data once the node is inserted. */
624 consumer_data
.stream_count
++;
625 consumer_data
.need_update
= 1;
628 pthread_mutex_unlock(&stream
->lock
);
629 pthread_mutex_unlock(&stream
->chan
->timer_lock
);
630 pthread_mutex_unlock(&stream
->chan
->lock
);
631 pthread_mutex_unlock(&consumer_data
.lock
);
636 void consumer_del_data_stream(struct lttng_consumer_stream
*stream
)
638 consumer_del_stream(stream
, data_ht
);
642 * Add relayd socket to global consumer data hashtable. RCU read side lock MUST
643 * be acquired before calling this.
645 static int add_relayd(struct consumer_relayd_sock_pair
*relayd
)
648 struct lttng_ht_node_u64
*node
;
649 struct lttng_ht_iter iter
;
653 lttng_ht_lookup(consumer_data
.relayd_ht
,
654 &relayd
->net_seq_idx
, &iter
);
655 node
= lttng_ht_iter_get_node_u64(&iter
);
659 lttng_ht_add_unique_u64(consumer_data
.relayd_ht
, &relayd
->node
);
666 * Allocate and return a consumer relayd socket.
668 struct consumer_relayd_sock_pair
*consumer_allocate_relayd_sock_pair(
669 uint64_t net_seq_idx
)
671 struct consumer_relayd_sock_pair
*obj
= NULL
;
673 /* net sequence index of -1 is a failure */
674 if (net_seq_idx
== (uint64_t) -1ULL) {
678 obj
= zmalloc(sizeof(struct consumer_relayd_sock_pair
));
680 PERROR("zmalloc relayd sock");
684 obj
->net_seq_idx
= net_seq_idx
;
686 obj
->destroy_flag
= 0;
687 obj
->control_sock
.sock
.fd
= -1;
688 obj
->data_sock
.sock
.fd
= -1;
689 lttng_ht_node_init_u64(&obj
->node
, obj
->net_seq_idx
);
690 pthread_mutex_init(&obj
->ctrl_sock_mutex
, NULL
);
697 * Find a relayd socket pair in the global consumer data.
699 * Return the object if found else NULL.
700 * RCU read-side lock must be held across this call and while using the
703 struct consumer_relayd_sock_pair
*consumer_find_relayd(uint64_t key
)
705 struct lttng_ht_iter iter
;
706 struct lttng_ht_node_u64
*node
;
707 struct consumer_relayd_sock_pair
*relayd
= NULL
;
709 /* Negative keys are lookup failures */
710 if (key
== (uint64_t) -1ULL) {
714 lttng_ht_lookup(consumer_data
.relayd_ht
, &key
,
716 node
= lttng_ht_iter_get_node_u64(&iter
);
718 relayd
= caa_container_of(node
, struct consumer_relayd_sock_pair
, node
);
726 * Find a relayd and send the stream
728 * Returns 0 on success, < 0 on error
730 int consumer_send_relayd_stream(struct lttng_consumer_stream
*stream
,
734 struct consumer_relayd_sock_pair
*relayd
;
737 assert(stream
->net_seq_idx
!= -1ULL);
740 /* The stream is not metadata. Get relayd reference if exists. */
742 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
743 if (relayd
!= NULL
) {
744 /* Add stream on the relayd */
745 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
746 ret
= relayd_add_stream(&relayd
->control_sock
, stream
->name
,
747 path
, &stream
->relayd_stream_id
,
748 stream
->chan
->tracefile_size
, stream
->chan
->tracefile_count
);
749 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
754 uatomic_inc(&relayd
->refcount
);
755 stream
->sent_to_relayd
= 1;
757 ERR("Stream %" PRIu64
" relayd ID %" PRIu64
" unknown. Can't send it.",
758 stream
->key
, stream
->net_seq_idx
);
763 DBG("Stream %s with key %" PRIu64
" sent to relayd id %" PRIu64
,
764 stream
->name
, stream
->key
, stream
->net_seq_idx
);
772 * Find a relayd and send the streams sent message
774 * Returns 0 on success, < 0 on error
776 int consumer_send_relayd_streams_sent(uint64_t net_seq_idx
)
779 struct consumer_relayd_sock_pair
*relayd
;
781 assert(net_seq_idx
!= -1ULL);
783 /* The stream is not metadata. Get relayd reference if exists. */
785 relayd
= consumer_find_relayd(net_seq_idx
);
786 if (relayd
!= NULL
) {
787 /* Add stream on the relayd */
788 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
789 ret
= relayd_streams_sent(&relayd
->control_sock
);
790 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
795 ERR("Relayd ID %" PRIu64
" unknown. Can't send streams_sent.",
802 DBG("All streams sent relayd id %" PRIu64
, net_seq_idx
);
810 * Find a relayd and close the stream
812 void close_relayd_stream(struct lttng_consumer_stream
*stream
)
814 struct consumer_relayd_sock_pair
*relayd
;
816 /* The stream is not metadata. Get relayd reference if exists. */
818 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
820 consumer_stream_relayd_close(stream
, relayd
);
826 * Handle stream for relayd transmission if the stream applies for network
827 * streaming where the net sequence index is set.
829 * Return destination file descriptor or negative value on error.
831 static int write_relayd_stream_header(struct lttng_consumer_stream
*stream
,
832 size_t data_size
, unsigned long padding
,
833 struct consumer_relayd_sock_pair
*relayd
)
836 struct lttcomm_relayd_data_hdr data_hdr
;
842 /* Reset data header */
843 memset(&data_hdr
, 0, sizeof(data_hdr
));
845 if (stream
->metadata_flag
) {
846 /* Caller MUST acquire the relayd control socket lock */
847 ret
= relayd_send_metadata(&relayd
->control_sock
, data_size
);
852 /* Metadata are always sent on the control socket. */
853 outfd
= relayd
->control_sock
.sock
.fd
;
855 /* Set header with stream information */
856 data_hdr
.stream_id
= htobe64(stream
->relayd_stream_id
);
857 data_hdr
.data_size
= htobe32(data_size
);
858 data_hdr
.padding_size
= htobe32(padding
);
860 * Note that net_seq_num below is assigned with the *current* value of
861 * next_net_seq_num and only after that the next_net_seq_num will be
862 * increment. This is why when issuing a command on the relayd using
863 * this next value, 1 should always be substracted in order to compare
864 * the last seen sequence number on the relayd side to the last sent.
866 data_hdr
.net_seq_num
= htobe64(stream
->next_net_seq_num
);
867 /* Other fields are zeroed previously */
869 ret
= relayd_send_data_hdr(&relayd
->data_sock
, &data_hdr
,
875 ++stream
->next_net_seq_num
;
877 /* Set to go on data socket */
878 outfd
= relayd
->data_sock
.sock
.fd
;
886 * Allocate and return a new lttng_consumer_channel object using the given key
887 * to initialize the hash table node.
889 * On error, return NULL.
891 struct lttng_consumer_channel
*consumer_allocate_channel(uint64_t key
,
893 const char *pathname
,
898 enum lttng_event_output output
,
899 uint64_t tracefile_size
,
900 uint64_t tracefile_count
,
901 uint64_t session_id_per_pid
,
902 unsigned int monitor
,
903 unsigned int live_timer_interval
)
905 struct lttng_consumer_channel
*channel
;
907 channel
= zmalloc(sizeof(*channel
));
908 if (channel
== NULL
) {
909 PERROR("malloc struct lttng_consumer_channel");
914 channel
->refcount
= 0;
915 channel
->session_id
= session_id
;
916 channel
->session_id_per_pid
= session_id_per_pid
;
919 channel
->relayd_id
= relayd_id
;
920 channel
->tracefile_size
= tracefile_size
;
921 channel
->tracefile_count
= tracefile_count
;
922 channel
->monitor
= monitor
;
923 channel
->live_timer_interval
= live_timer_interval
;
924 pthread_mutex_init(&channel
->lock
, NULL
);
925 pthread_mutex_init(&channel
->timer_lock
, NULL
);
928 case LTTNG_EVENT_SPLICE
:
929 channel
->output
= CONSUMER_CHANNEL_SPLICE
;
931 case LTTNG_EVENT_MMAP
:
932 channel
->output
= CONSUMER_CHANNEL_MMAP
;
942 * In monitor mode, the streams associated with the channel will be put in
943 * a special list ONLY owned by this channel. So, the refcount is set to 1
944 * here meaning that the channel itself has streams that are referenced.
946 * On a channel deletion, once the channel is no longer visible, the
947 * refcount is decremented and checked for a zero value to delete it. With
948 * streams in no monitor mode, it will now be safe to destroy the channel.
950 if (!channel
->monitor
) {
951 channel
->refcount
= 1;
954 strncpy(channel
->pathname
, pathname
, sizeof(channel
->pathname
));
955 channel
->pathname
[sizeof(channel
->pathname
) - 1] = '\0';
957 strncpy(channel
->name
, name
, sizeof(channel
->name
));
958 channel
->name
[sizeof(channel
->name
) - 1] = '\0';
960 lttng_ht_node_init_u64(&channel
->node
, channel
->key
);
962 channel
->wait_fd
= -1;
964 CDS_INIT_LIST_HEAD(&channel
->streams
.head
);
966 DBG("Allocated channel (key %" PRIu64
")", channel
->key
)
973 * Add a channel to the global list protected by a mutex.
975 * On success 0 is returned else a negative value.
977 int consumer_add_channel(struct lttng_consumer_channel
*channel
,
978 struct lttng_consumer_local_data
*ctx
)
981 struct lttng_ht_node_u64
*node
;
982 struct lttng_ht_iter iter
;
984 pthread_mutex_lock(&consumer_data
.lock
);
985 pthread_mutex_lock(&channel
->lock
);
986 pthread_mutex_lock(&channel
->timer_lock
);
989 lttng_ht_lookup(consumer_data
.channel_ht
, &channel
->key
, &iter
);
990 node
= lttng_ht_iter_get_node_u64(&iter
);
992 /* Channel already exist. Ignore the insertion */
993 ERR("Consumer add channel key %" PRIu64
" already exists!",
999 lttng_ht_add_unique_u64(consumer_data
.channel_ht
, &channel
->node
);
1003 pthread_mutex_unlock(&channel
->timer_lock
);
1004 pthread_mutex_unlock(&channel
->lock
);
1005 pthread_mutex_unlock(&consumer_data
.lock
);
1007 if (!ret
&& channel
->wait_fd
!= -1 &&
1008 channel
->type
== CONSUMER_CHANNEL_TYPE_DATA
) {
1009 notify_channel_pipe(ctx
, channel
, -1, CONSUMER_CHANNEL_ADD
);
1015 * Allocate the pollfd structure and the local view of the out fds to avoid
1016 * doing a lookup in the linked list and concurrency issues when writing is
1017 * needed. Called with consumer_data.lock held.
1019 * Returns the number of fds in the structures.
1021 static int update_poll_array(struct lttng_consumer_local_data
*ctx
,
1022 struct pollfd
**pollfd
, struct lttng_consumer_stream
**local_stream
,
1023 struct lttng_ht
*ht
)
1026 struct lttng_ht_iter iter
;
1027 struct lttng_consumer_stream
*stream
;
1032 assert(local_stream
);
1034 DBG("Updating poll fd array");
1036 cds_lfht_for_each_entry(ht
->ht
, &iter
.iter
, stream
, node
.node
) {
1038 * Only active streams with an active end point can be added to the
1039 * poll set and local stream storage of the thread.
1041 * There is a potential race here for endpoint_status to be updated
1042 * just after the check. However, this is OK since the stream(s) will
1043 * be deleted once the thread is notified that the end point state has
1044 * changed where this function will be called back again.
1046 if (stream
->state
!= LTTNG_CONSUMER_ACTIVE_STREAM
||
1047 stream
->endpoint_status
== CONSUMER_ENDPOINT_INACTIVE
) {
1051 * This clobbers way too much the debug output. Uncomment that if you
1052 * need it for debugging purposes.
1054 * DBG("Active FD %d", stream->wait_fd);
1056 (*pollfd
)[i
].fd
= stream
->wait_fd
;
1057 (*pollfd
)[i
].events
= POLLIN
| POLLPRI
;
1058 local_stream
[i
] = stream
;
1064 * Insert the consumer_data_pipe at the end of the array and don't
1065 * increment i so nb_fd is the number of real FD.
1067 (*pollfd
)[i
].fd
= lttng_pipe_get_readfd(ctx
->consumer_data_pipe
);
1068 (*pollfd
)[i
].events
= POLLIN
| POLLPRI
;
1073 * Poll on the should_quit pipe and the command socket return -1 on error and
1074 * should exit, 0 if data is available on the command socket
1076 int lttng_consumer_poll_socket(struct pollfd
*consumer_sockpoll
)
1081 num_rdy
= poll(consumer_sockpoll
, 2, -1);
1082 if (num_rdy
== -1) {
1084 * Restart interrupted system call.
1086 if (errno
== EINTR
) {
1089 PERROR("Poll error");
1092 if (consumer_sockpoll
[0].revents
& (POLLIN
| POLLPRI
)) {
1093 DBG("consumer_should_quit wake up");
1103 * Set the error socket.
1105 void lttng_consumer_set_error_sock(struct lttng_consumer_local_data
*ctx
,
1108 ctx
->consumer_error_socket
= sock
;
1112 * Set the command socket path.
1114 void lttng_consumer_set_command_sock_path(
1115 struct lttng_consumer_local_data
*ctx
, char *sock
)
1117 ctx
->consumer_command_sock_path
= sock
;
1121 * Send return code to the session daemon.
1122 * If the socket is not defined, we return 0, it is not a fatal error
1124 int lttng_consumer_send_error(struct lttng_consumer_local_data
*ctx
, int cmd
)
1126 if (ctx
->consumer_error_socket
> 0) {
1127 return lttcomm_send_unix_sock(ctx
->consumer_error_socket
, &cmd
,
1128 sizeof(enum lttcomm_sessiond_command
));
1135 * Close all the tracefiles and stream fds and MUST be called when all
1136 * instances are destroyed i.e. when all threads were joined and are ended.
1138 void lttng_consumer_cleanup(void)
1140 struct lttng_ht_iter iter
;
1141 struct lttng_consumer_channel
*channel
;
1145 cds_lfht_for_each_entry(consumer_data
.channel_ht
->ht
, &iter
.iter
, channel
,
1147 consumer_del_channel(channel
);
1152 lttng_ht_destroy(consumer_data
.channel_ht
);
1154 cleanup_relayd_ht();
1156 lttng_ht_destroy(consumer_data
.stream_per_chan_id_ht
);
1159 * This HT contains streams that are freed by either the metadata thread or
1160 * the data thread so we do *nothing* on the hash table and simply destroy
1163 lttng_ht_destroy(consumer_data
.stream_list_ht
);
1167 * Called from signal handler.
1169 void lttng_consumer_should_exit(struct lttng_consumer_local_data
*ctx
)
1174 ret
= lttng_write(ctx
->consumer_should_quit
[1], "4", 1);
1176 PERROR("write consumer quit");
1179 DBG("Consumer flag that it should quit");
1182 void lttng_consumer_sync_trace_file(struct lttng_consumer_stream
*stream
,
1185 int outfd
= stream
->out_fd
;
1188 * This does a blocking write-and-wait on any page that belongs to the
1189 * subbuffer prior to the one we just wrote.
1190 * Don't care about error values, as these are just hints and ways to
1191 * limit the amount of page cache used.
1193 if (orig_offset
< stream
->max_sb_size
) {
1196 lttng_sync_file_range(outfd
, orig_offset
- stream
->max_sb_size
,
1197 stream
->max_sb_size
,
1198 SYNC_FILE_RANGE_WAIT_BEFORE
1199 | SYNC_FILE_RANGE_WRITE
1200 | SYNC_FILE_RANGE_WAIT_AFTER
);
1202 * Give hints to the kernel about how we access the file:
1203 * POSIX_FADV_DONTNEED : we won't re-access data in a near future after
1206 * We need to call fadvise again after the file grows because the
1207 * kernel does not seem to apply fadvise to non-existing parts of the
1210 * Call fadvise _after_ having waited for the page writeback to
1211 * complete because the dirty page writeback semantic is not well
1212 * defined. So it can be expected to lead to lower throughput in
1215 posix_fadvise(outfd
, orig_offset
- stream
->max_sb_size
,
1216 stream
->max_sb_size
, POSIX_FADV_DONTNEED
);
1220 * Initialise the necessary environnement :
1221 * - create a new context
1222 * - create the poll_pipe
1223 * - create the should_quit pipe (for signal handler)
1224 * - create the thread pipe (for splice)
1226 * Takes a function pointer as argument, this function is called when data is
1227 * available on a buffer. This function is responsible to do the
1228 * kernctl_get_next_subbuf, read the data with mmap or splice depending on the
1229 * buffer configuration and then kernctl_put_next_subbuf at the end.
1231 * Returns a pointer to the new context or NULL on error.
1233 struct lttng_consumer_local_data
*lttng_consumer_create(
1234 enum lttng_consumer_type type
,
1235 ssize_t (*buffer_ready
)(struct lttng_consumer_stream
*stream
,
1236 struct lttng_consumer_local_data
*ctx
),
1237 int (*recv_channel
)(struct lttng_consumer_channel
*channel
),
1238 int (*recv_stream
)(struct lttng_consumer_stream
*stream
),
1239 int (*update_stream
)(uint64_t stream_key
, uint32_t state
))
1242 struct lttng_consumer_local_data
*ctx
;
1244 assert(consumer_data
.type
== LTTNG_CONSUMER_UNKNOWN
||
1245 consumer_data
.type
== type
);
1246 consumer_data
.type
= type
;
1248 ctx
= zmalloc(sizeof(struct lttng_consumer_local_data
));
1250 PERROR("allocating context");
1254 ctx
->consumer_error_socket
= -1;
1255 ctx
->consumer_metadata_socket
= -1;
1256 pthread_mutex_init(&ctx
->metadata_socket_lock
, NULL
);
1257 /* assign the callbacks */
1258 ctx
->on_buffer_ready
= buffer_ready
;
1259 ctx
->on_recv_channel
= recv_channel
;
1260 ctx
->on_recv_stream
= recv_stream
;
1261 ctx
->on_update_stream
= update_stream
;
1263 ctx
->consumer_data_pipe
= lttng_pipe_open(0);
1264 if (!ctx
->consumer_data_pipe
) {
1265 goto error_poll_pipe
;
1268 ret
= pipe(ctx
->consumer_should_quit
);
1270 PERROR("Error creating recv pipe");
1271 goto error_quit_pipe
;
1274 ret
= pipe(ctx
->consumer_thread_pipe
);
1276 PERROR("Error creating thread pipe");
1277 goto error_thread_pipe
;
1280 ret
= pipe(ctx
->consumer_channel_pipe
);
1282 PERROR("Error creating channel pipe");
1283 goto error_channel_pipe
;
1286 ctx
->consumer_metadata_pipe
= lttng_pipe_open(0);
1287 if (!ctx
->consumer_metadata_pipe
) {
1288 goto error_metadata_pipe
;
1291 ret
= utils_create_pipe(ctx
->consumer_splice_metadata_pipe
);
1293 goto error_splice_pipe
;
1299 lttng_pipe_destroy(ctx
->consumer_metadata_pipe
);
1300 error_metadata_pipe
:
1301 utils_close_pipe(ctx
->consumer_channel_pipe
);
1303 utils_close_pipe(ctx
->consumer_thread_pipe
);
1305 utils_close_pipe(ctx
->consumer_should_quit
);
1307 lttng_pipe_destroy(ctx
->consumer_data_pipe
);
1315 * Iterate over all streams of the hashtable and free them properly.
1317 static void destroy_data_stream_ht(struct lttng_ht
*ht
)
1319 struct lttng_ht_iter iter
;
1320 struct lttng_consumer_stream
*stream
;
1327 cds_lfht_for_each_entry(ht
->ht
, &iter
.iter
, stream
, node
.node
) {
1329 * Ignore return value since we are currently cleaning up so any error
1332 (void) consumer_del_stream(stream
, ht
);
1336 lttng_ht_destroy(ht
);
1340 * Iterate over all streams of the metadata hashtable and free them
1343 static void destroy_metadata_stream_ht(struct lttng_ht
*ht
)
1345 struct lttng_ht_iter iter
;
1346 struct lttng_consumer_stream
*stream
;
1353 cds_lfht_for_each_entry(ht
->ht
, &iter
.iter
, stream
, node
.node
) {
1355 * Ignore return value since we are currently cleaning up so any error
1358 (void) consumer_del_metadata_stream(stream
, ht
);
1362 lttng_ht_destroy(ht
);
1366 * Close all fds associated with the instance and free the context.
1368 void lttng_consumer_destroy(struct lttng_consumer_local_data
*ctx
)
1372 DBG("Consumer destroying it. Closing everything.");
1374 destroy_data_stream_ht(data_ht
);
1375 destroy_metadata_stream_ht(metadata_ht
);
1377 ret
= close(ctx
->consumer_error_socket
);
1381 ret
= close(ctx
->consumer_metadata_socket
);
1385 utils_close_pipe(ctx
->consumer_thread_pipe
);
1386 utils_close_pipe(ctx
->consumer_channel_pipe
);
1387 lttng_pipe_destroy(ctx
->consumer_data_pipe
);
1388 lttng_pipe_destroy(ctx
->consumer_metadata_pipe
);
1389 utils_close_pipe(ctx
->consumer_should_quit
);
1390 utils_close_pipe(ctx
->consumer_splice_metadata_pipe
);
1392 unlink(ctx
->consumer_command_sock_path
);
1397 * Write the metadata stream id on the specified file descriptor.
1399 static int write_relayd_metadata_id(int fd
,
1400 struct lttng_consumer_stream
*stream
,
1401 struct consumer_relayd_sock_pair
*relayd
, unsigned long padding
)
1404 struct lttcomm_relayd_metadata_payload hdr
;
1406 hdr
.stream_id
= htobe64(stream
->relayd_stream_id
);
1407 hdr
.padding_size
= htobe32(padding
);
1408 ret
= lttng_write(fd
, (void *) &hdr
, sizeof(hdr
));
1409 if (ret
< sizeof(hdr
)) {
1411 * This error means that the fd's end is closed so ignore the perror
1412 * not to clubber the error output since this can happen in a normal
1415 if (errno
!= EPIPE
) {
1416 PERROR("write metadata stream id");
1418 DBG3("Consumer failed to write relayd metadata id (errno: %d)", errno
);
1420 * Set ret to a negative value because if ret != sizeof(hdr), we don't
1421 * handle writting the missing part so report that as an error and
1422 * don't lie to the caller.
1427 DBG("Metadata stream id %" PRIu64
" with padding %lu written before data",
1428 stream
->relayd_stream_id
, padding
);
1435 * Mmap the ring buffer, read it and write the data to the tracefile. This is a
1436 * core function for writing trace buffers to either the local filesystem or
1439 * It must be called with the stream lock held.
1441 * Careful review MUST be put if any changes occur!
1443 * Returns the number of bytes written
1445 ssize_t
lttng_consumer_on_read_subbuffer_mmap(
1446 struct lttng_consumer_local_data
*ctx
,
1447 struct lttng_consumer_stream
*stream
, unsigned long len
,
1448 unsigned long padding
,
1449 struct ctf_packet_index
*index
)
1451 unsigned long mmap_offset
;
1453 ssize_t ret
= 0, written
= 0;
1454 off_t orig_offset
= stream
->out_fd_offset
;
1455 /* Default is on the disk */
1456 int outfd
= stream
->out_fd
;
1457 struct consumer_relayd_sock_pair
*relayd
= NULL
;
1458 unsigned int relayd_hang_up
= 0;
1460 /* RCU lock for the relayd pointer */
1463 /* Flag that the current stream if set for network streaming. */
1464 if (stream
->net_seq_idx
!= (uint64_t) -1ULL) {
1465 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
1466 if (relayd
== NULL
) {
1472 /* get the offset inside the fd to mmap */
1473 switch (consumer_data
.type
) {
1474 case LTTNG_CONSUMER_KERNEL
:
1475 mmap_base
= stream
->mmap_base
;
1476 ret
= kernctl_get_mmap_read_offset(stream
->wait_fd
, &mmap_offset
);
1478 PERROR("tracer ctl get_mmap_read_offset");
1483 case LTTNG_CONSUMER32_UST
:
1484 case LTTNG_CONSUMER64_UST
:
1485 mmap_base
= lttng_ustctl_get_mmap_base(stream
);
1487 ERR("read mmap get mmap base for stream %s", stream
->name
);
1491 ret
= lttng_ustctl_get_mmap_read_offset(stream
, &mmap_offset
);
1493 PERROR("tracer ctl get_mmap_read_offset");
1499 ERR("Unknown consumer_data type");
1503 /* Handle stream on the relayd if the output is on the network */
1505 unsigned long netlen
= len
;
1508 * Lock the control socket for the complete duration of the function
1509 * since from this point on we will use the socket.
1511 if (stream
->metadata_flag
) {
1512 /* Metadata requires the control socket. */
1513 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
1514 netlen
+= sizeof(struct lttcomm_relayd_metadata_payload
);
1517 ret
= write_relayd_stream_header(stream
, netlen
, padding
, relayd
);
1519 /* Use the returned socket. */
1522 /* Write metadata stream id before payload */
1523 if (stream
->metadata_flag
) {
1524 ret
= write_relayd_metadata_id(outfd
, stream
, relayd
, padding
);
1527 /* Socket operation failed. We consider the relayd dead */
1528 if (ret
== -EPIPE
|| ret
== -EINVAL
) {
1536 /* Socket operation failed. We consider the relayd dead */
1537 if (ret
== -EPIPE
|| ret
== -EINVAL
) {
1541 /* Else, use the default set before which is the filesystem. */
1544 /* No streaming, we have to set the len with the full padding */
1548 * Check if we need to change the tracefile before writing the packet.
1550 if (stream
->chan
->tracefile_size
> 0 &&
1551 (stream
->tracefile_size_current
+ len
) >
1552 stream
->chan
->tracefile_size
) {
1553 ret
= utils_rotate_stream_file(stream
->chan
->pathname
,
1554 stream
->name
, stream
->chan
->tracefile_size
,
1555 stream
->chan
->tracefile_count
, stream
->uid
, stream
->gid
,
1556 stream
->out_fd
, &(stream
->tracefile_count_current
),
1559 ERR("Rotating output file");
1562 outfd
= stream
->out_fd
;
1564 if (stream
->index_fd
>= 0) {
1565 ret
= index_create_file(stream
->chan
->pathname
,
1566 stream
->name
, stream
->uid
, stream
->gid
,
1567 stream
->chan
->tracefile_size
,
1568 stream
->tracefile_count_current
);
1572 stream
->index_fd
= ret
;
1575 /* Reset current size because we just perform a rotation. */
1576 stream
->tracefile_size_current
= 0;
1577 stream
->out_fd_offset
= 0;
1580 stream
->tracefile_size_current
+= len
;
1582 index
->offset
= htobe64(stream
->out_fd_offset
);
1587 ret
= lttng_write(outfd
, mmap_base
+ mmap_offset
, len
);
1588 DBG("Consumer mmap write() ret %zd (len %lu)", ret
, len
);
1591 * This is possible if the fd is closed on the other side (outfd)
1592 * or any write problem. It can be verbose a bit for a normal
1593 * execution if for instance the relayd is stopped abruptly. This
1594 * can happen so set this to a DBG statement.
1596 DBG("Error in file write mmap");
1600 /* Socket operation failed. We consider the relayd dead */
1601 if (errno
== EPIPE
|| errno
== EINVAL
) {
1606 } else if (ret
> len
) {
1607 PERROR("Error in file write (ret %zd > len %lu)", ret
, len
);
1615 /* This call is useless on a socket so better save a syscall. */
1617 /* This won't block, but will start writeout asynchronously */
1618 lttng_sync_file_range(outfd
, stream
->out_fd_offset
, ret
,
1619 SYNC_FILE_RANGE_WRITE
);
1620 stream
->out_fd_offset
+= ret
;
1622 stream
->output_written
+= ret
;
1625 lttng_consumer_sync_trace_file(stream
, orig_offset
);
1629 * This is a special case that the relayd has closed its socket. Let's
1630 * cleanup the relayd object and all associated streams.
1632 if (relayd
&& relayd_hang_up
) {
1633 cleanup_relayd(relayd
, ctx
);
1637 /* Unlock only if ctrl socket used */
1638 if (relayd
&& stream
->metadata_flag
) {
1639 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
1647 * Splice the data from the ring buffer to the tracefile.
1649 * It must be called with the stream lock held.
1651 * Returns the number of bytes spliced.
1653 ssize_t
lttng_consumer_on_read_subbuffer_splice(
1654 struct lttng_consumer_local_data
*ctx
,
1655 struct lttng_consumer_stream
*stream
, unsigned long len
,
1656 unsigned long padding
,
1657 struct ctf_packet_index
*index
)
1659 ssize_t ret
= 0, written
= 0, ret_splice
= 0;
1661 off_t orig_offset
= stream
->out_fd_offset
;
1662 int fd
= stream
->wait_fd
;
1663 /* Default is on the disk */
1664 int outfd
= stream
->out_fd
;
1665 struct consumer_relayd_sock_pair
*relayd
= NULL
;
1667 unsigned int relayd_hang_up
= 0;
1669 switch (consumer_data
.type
) {
1670 case LTTNG_CONSUMER_KERNEL
:
1672 case LTTNG_CONSUMER32_UST
:
1673 case LTTNG_CONSUMER64_UST
:
1674 /* Not supported for user space tracing */
1677 ERR("Unknown consumer_data type");
1681 /* RCU lock for the relayd pointer */
1684 /* Flag that the current stream if set for network streaming. */
1685 if (stream
->net_seq_idx
!= (uint64_t) -1ULL) {
1686 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
1687 if (relayd
== NULL
) {
1694 * Choose right pipe for splice. Metadata and trace data are handled by
1695 * different threads hence the use of two pipes in order not to race or
1696 * corrupt the written data.
1698 if (stream
->metadata_flag
) {
1699 splice_pipe
= ctx
->consumer_splice_metadata_pipe
;
1701 splice_pipe
= ctx
->consumer_thread_pipe
;
1704 /* Write metadata stream id before payload */
1706 int total_len
= len
;
1708 if (stream
->metadata_flag
) {
1710 * Lock the control socket for the complete duration of the function
1711 * since from this point on we will use the socket.
1713 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
1715 ret
= write_relayd_metadata_id(splice_pipe
[1], stream
, relayd
,
1719 /* Socket operation failed. We consider the relayd dead */
1720 if (ret
== -EBADF
) {
1721 WARN("Remote relayd disconnected. Stopping");
1728 total_len
+= sizeof(struct lttcomm_relayd_metadata_payload
);
1731 ret
= write_relayd_stream_header(stream
, total_len
, padding
, relayd
);
1733 /* Use the returned socket. */
1736 /* Socket operation failed. We consider the relayd dead */
1737 if (ret
== -EBADF
) {
1738 WARN("Remote relayd disconnected. Stopping");
1745 /* No streaming, we have to set the len with the full padding */
1749 * Check if we need to change the tracefile before writing the packet.
1751 if (stream
->chan
->tracefile_size
> 0 &&
1752 (stream
->tracefile_size_current
+ len
) >
1753 stream
->chan
->tracefile_size
) {
1754 ret
= utils_rotate_stream_file(stream
->chan
->pathname
,
1755 stream
->name
, stream
->chan
->tracefile_size
,
1756 stream
->chan
->tracefile_count
, stream
->uid
, stream
->gid
,
1757 stream
->out_fd
, &(stream
->tracefile_count_current
),
1760 ERR("Rotating output file");
1763 outfd
= stream
->out_fd
;
1765 if (stream
->index_fd
>= 0) {
1766 ret
= index_create_file(stream
->chan
->pathname
,
1767 stream
->name
, stream
->uid
, stream
->gid
,
1768 stream
->chan
->tracefile_size
,
1769 stream
->tracefile_count_current
);
1773 stream
->index_fd
= ret
;
1776 /* Reset current size because we just perform a rotation. */
1777 stream
->tracefile_size_current
= 0;
1778 stream
->out_fd_offset
= 0;
1781 stream
->tracefile_size_current
+= len
;
1782 index
->offset
= htobe64(stream
->out_fd_offset
);
1786 DBG("splice chan to pipe offset %lu of len %lu (fd : %d, pipe: %d)",
1787 (unsigned long)offset
, len
, fd
, splice_pipe
[1]);
1788 ret_splice
= splice(fd
, &offset
, splice_pipe
[1], NULL
, len
,
1789 SPLICE_F_MOVE
| SPLICE_F_MORE
);
1790 DBG("splice chan to pipe, ret %zd", ret_splice
);
1791 if (ret_splice
< 0) {
1792 PERROR("Error in relay splice");
1794 written
= ret_splice
;
1800 /* Handle stream on the relayd if the output is on the network */
1802 if (stream
->metadata_flag
) {
1803 size_t metadata_payload_size
=
1804 sizeof(struct lttcomm_relayd_metadata_payload
);
1806 /* Update counter to fit the spliced data */
1807 ret_splice
+= metadata_payload_size
;
1808 len
+= metadata_payload_size
;
1810 * We do this so the return value can match the len passed as
1811 * argument to this function.
1813 written
-= metadata_payload_size
;
1817 /* Splice data out */
1818 ret_splice
= splice(splice_pipe
[0], NULL
, outfd
, NULL
,
1819 ret_splice
, SPLICE_F_MOVE
| SPLICE_F_MORE
);
1820 DBG("Consumer splice pipe to file, ret %zd", ret_splice
);
1821 if (ret_splice
< 0) {
1822 PERROR("Error in file splice");
1824 written
= ret_splice
;
1826 /* Socket operation failed. We consider the relayd dead */
1827 if (errno
== EBADF
|| errno
== EPIPE
) {
1828 WARN("Remote relayd disconnected. Stopping");
1834 } else if (ret_splice
> len
) {
1836 PERROR("Wrote more data than requested %zd (len: %lu)",
1838 written
+= ret_splice
;
1844 /* This call is useless on a socket so better save a syscall. */
1846 /* This won't block, but will start writeout asynchronously */
1847 lttng_sync_file_range(outfd
, stream
->out_fd_offset
, ret_splice
,
1848 SYNC_FILE_RANGE_WRITE
);
1849 stream
->out_fd_offset
+= ret_splice
;
1851 stream
->output_written
+= ret_splice
;
1852 written
+= ret_splice
;
1854 lttng_consumer_sync_trace_file(stream
, orig_offset
);
1862 * This is a special case that the relayd has closed its socket. Let's
1863 * cleanup the relayd object and all associated streams.
1865 if (relayd
&& relayd_hang_up
) {
1866 cleanup_relayd(relayd
, ctx
);
1867 /* Skip splice error so the consumer does not fail */
1872 /* send the appropriate error description to sessiond */
1875 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_SPLICE_EINVAL
);
1878 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_SPLICE_ENOMEM
);
1881 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_SPLICE_ESPIPE
);
1886 if (relayd
&& stream
->metadata_flag
) {
1887 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
1895 * Take a snapshot for a specific fd
1897 * Returns 0 on success, < 0 on error
1899 int lttng_consumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1901 switch (consumer_data
.type
) {
1902 case LTTNG_CONSUMER_KERNEL
:
1903 return lttng_kconsumer_take_snapshot(stream
);
1904 case LTTNG_CONSUMER32_UST
:
1905 case LTTNG_CONSUMER64_UST
:
1906 return lttng_ustconsumer_take_snapshot(stream
);
1908 ERR("Unknown consumer_data type");
1915 * Get the produced position
1917 * Returns 0 on success, < 0 on error
1919 int lttng_consumer_get_produced_snapshot(struct lttng_consumer_stream
*stream
,
1922 switch (consumer_data
.type
) {
1923 case LTTNG_CONSUMER_KERNEL
:
1924 return lttng_kconsumer_get_produced_snapshot(stream
, pos
);
1925 case LTTNG_CONSUMER32_UST
:
1926 case LTTNG_CONSUMER64_UST
:
1927 return lttng_ustconsumer_get_produced_snapshot(stream
, pos
);
1929 ERR("Unknown consumer_data type");
1935 int lttng_consumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1936 int sock
, struct pollfd
*consumer_sockpoll
)
1938 switch (consumer_data
.type
) {
1939 case LTTNG_CONSUMER_KERNEL
:
1940 return lttng_kconsumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
1941 case LTTNG_CONSUMER32_UST
:
1942 case LTTNG_CONSUMER64_UST
:
1943 return lttng_ustconsumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
1945 ERR("Unknown consumer_data type");
1951 void lttng_consumer_close_metadata(void)
1953 switch (consumer_data
.type
) {
1954 case LTTNG_CONSUMER_KERNEL
:
1956 * The Kernel consumer has a different metadata scheme so we don't
1957 * close anything because the stream will be closed by the session
1961 case LTTNG_CONSUMER32_UST
:
1962 case LTTNG_CONSUMER64_UST
:
1964 * Close all metadata streams. The metadata hash table is passed and
1965 * this call iterates over it by closing all wakeup fd. This is safe
1966 * because at this point we are sure that the metadata producer is
1967 * either dead or blocked.
1969 lttng_ustconsumer_close_metadata(metadata_ht
);
1972 ERR("Unknown consumer_data type");
1978 * Clean up a metadata stream and free its memory.
1980 void consumer_del_metadata_stream(struct lttng_consumer_stream
*stream
,
1981 struct lttng_ht
*ht
)
1984 struct lttng_ht_iter iter
;
1985 struct lttng_consumer_channel
*free_chan
= NULL
;
1986 struct consumer_relayd_sock_pair
*relayd
;
1990 * This call should NEVER receive regular stream. It must always be
1991 * metadata stream and this is crucial for data structure synchronization.
1993 assert(stream
->metadata_flag
);
1995 DBG3("Consumer delete metadata stream %d", stream
->wait_fd
);
1998 /* Means the stream was allocated but not successfully added */
1999 goto free_stream_rcu
;
2002 pthread_mutex_lock(&consumer_data
.lock
);
2003 pthread_mutex_lock(&stream
->chan
->lock
);
2004 pthread_mutex_lock(&stream
->lock
);
2006 switch (consumer_data
.type
) {
2007 case LTTNG_CONSUMER_KERNEL
:
2008 if (stream
->mmap_base
!= NULL
) {
2009 ret
= munmap(stream
->mmap_base
, stream
->mmap_len
);
2011 PERROR("munmap metadata stream");
2014 if (stream
->wait_fd
>= 0) {
2015 ret
= close(stream
->wait_fd
);
2017 PERROR("close kernel metadata wait_fd");
2021 case LTTNG_CONSUMER32_UST
:
2022 case LTTNG_CONSUMER64_UST
:
2023 if (stream
->monitor
) {
2024 /* close the write-side in close_metadata */
2025 ret
= close(stream
->ust_metadata_poll_pipe
[0]);
2027 PERROR("Close UST metadata read-side poll pipe");
2030 lttng_ustconsumer_del_stream(stream
);
2033 ERR("Unknown consumer_data type");
2039 iter
.iter
.node
= &stream
->node
.node
;
2040 ret
= lttng_ht_del(ht
, &iter
);
2043 iter
.iter
.node
= &stream
->node_channel_id
.node
;
2044 ret
= lttng_ht_del(consumer_data
.stream_per_chan_id_ht
, &iter
);
2047 iter
.iter
.node
= &stream
->node_session_id
.node
;
2048 ret
= lttng_ht_del(consumer_data
.stream_list_ht
, &iter
);
2052 if (stream
->out_fd
>= 0) {
2053 ret
= close(stream
->out_fd
);
2059 /* Check and cleanup relayd */
2061 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
2062 if (relayd
!= NULL
) {
2063 uatomic_dec(&relayd
->refcount
);
2064 assert(uatomic_read(&relayd
->refcount
) >= 0);
2066 /* Closing streams requires to lock the control socket. */
2067 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
2068 ret
= relayd_send_close_stream(&relayd
->control_sock
,
2069 stream
->relayd_stream_id
, stream
->next_net_seq_num
- 1);
2070 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
2072 DBG("Unable to close stream on the relayd. Continuing");
2074 * Continue here. There is nothing we can do for the relayd.
2075 * Chances are that the relayd has closed the socket so we just
2076 * continue cleaning up.
2080 /* Both conditions are met, we destroy the relayd. */
2081 if (uatomic_read(&relayd
->refcount
) == 0 &&
2082 uatomic_read(&relayd
->destroy_flag
)) {
2083 consumer_destroy_relayd(relayd
);
2088 /* Atomically decrement channel refcount since other threads can use it. */
2089 if (!uatomic_sub_return(&stream
->chan
->refcount
, 1)
2090 && !uatomic_read(&stream
->chan
->nb_init_stream_left
)) {
2091 /* Go for channel deletion! */
2092 free_chan
= stream
->chan
;
2097 * Nullify the stream reference so it is not used after deletion. The
2098 * channel lock MUST be acquired before being able to check for
2099 * a NULL pointer value.
2101 stream
->chan
->metadata_stream
= NULL
;
2103 pthread_mutex_unlock(&stream
->lock
);
2104 pthread_mutex_unlock(&stream
->chan
->lock
);
2105 pthread_mutex_unlock(&consumer_data
.lock
);
2108 consumer_del_channel(free_chan
);
2112 call_rcu(&stream
->node
.head
, free_stream_rcu
);
2116 * Action done with the metadata stream when adding it to the consumer internal
2117 * data structures to handle it.
2119 int consumer_add_metadata_stream(struct lttng_consumer_stream
*stream
)
2121 struct lttng_ht
*ht
= metadata_ht
;
2123 struct lttng_ht_iter iter
;
2124 struct lttng_ht_node_u64
*node
;
2129 DBG3("Adding metadata stream %" PRIu64
" to hash table", stream
->key
);
2131 pthread_mutex_lock(&consumer_data
.lock
);
2132 pthread_mutex_lock(&stream
->chan
->lock
);
2133 pthread_mutex_lock(&stream
->chan
->timer_lock
);
2134 pthread_mutex_lock(&stream
->lock
);
2137 * From here, refcounts are updated so be _careful_ when returning an error
2144 * Lookup the stream just to make sure it does not exist in our internal
2145 * state. This should NEVER happen.
2147 lttng_ht_lookup(ht
, &stream
->key
, &iter
);
2148 node
= lttng_ht_iter_get_node_u64(&iter
);
2152 * When nb_init_stream_left reaches 0, we don't need to trigger any action
2153 * in terms of destroying the associated channel, because the action that
2154 * causes the count to become 0 also causes a stream to be added. The
2155 * channel deletion will thus be triggered by the following removal of this
2158 if (uatomic_read(&stream
->chan
->nb_init_stream_left
) > 0) {
2159 /* Increment refcount before decrementing nb_init_stream_left */
2161 uatomic_dec(&stream
->chan
->nb_init_stream_left
);
2164 lttng_ht_add_unique_u64(ht
, &stream
->node
);
2166 lttng_ht_add_unique_u64(consumer_data
.stream_per_chan_id_ht
,
2167 &stream
->node_channel_id
);
2170 * Add stream to the stream_list_ht of the consumer data. No need to steal
2171 * the key since the HT does not use it and we allow to add redundant keys
2174 lttng_ht_add_u64(consumer_data
.stream_list_ht
, &stream
->node_session_id
);
2178 pthread_mutex_unlock(&stream
->lock
);
2179 pthread_mutex_unlock(&stream
->chan
->lock
);
2180 pthread_mutex_unlock(&stream
->chan
->timer_lock
);
2181 pthread_mutex_unlock(&consumer_data
.lock
);
2186 * Delete data stream that are flagged for deletion (endpoint_status).
2188 static void validate_endpoint_status_data_stream(void)
2190 struct lttng_ht_iter iter
;
2191 struct lttng_consumer_stream
*stream
;
2193 DBG("Consumer delete flagged data stream");
2196 cds_lfht_for_each_entry(data_ht
->ht
, &iter
.iter
, stream
, node
.node
) {
2197 /* Validate delete flag of the stream */
2198 if (stream
->endpoint_status
== CONSUMER_ENDPOINT_ACTIVE
) {
2201 /* Delete it right now */
2202 consumer_del_stream(stream
, data_ht
);
2208 * Delete metadata stream that are flagged for deletion (endpoint_status).
2210 static void validate_endpoint_status_metadata_stream(
2211 struct lttng_poll_event
*pollset
)
2213 struct lttng_ht_iter iter
;
2214 struct lttng_consumer_stream
*stream
;
2216 DBG("Consumer delete flagged metadata stream");
2221 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
, node
.node
) {
2222 /* Validate delete flag of the stream */
2223 if (stream
->endpoint_status
== CONSUMER_ENDPOINT_ACTIVE
) {
2227 * Remove from pollset so the metadata thread can continue without
2228 * blocking on a deleted stream.
2230 lttng_poll_del(pollset
, stream
->wait_fd
);
2232 /* Delete it right now */
2233 consumer_del_metadata_stream(stream
, metadata_ht
);
2239 * Thread polls on metadata file descriptor and write them on disk or on the
2242 void *consumer_thread_metadata_poll(void *data
)
2244 int ret
, i
, pollfd
, err
= -1;
2245 uint32_t revents
, nb_fd
;
2246 struct lttng_consumer_stream
*stream
= NULL
;
2247 struct lttng_ht_iter iter
;
2248 struct lttng_ht_node_u64
*node
;
2249 struct lttng_poll_event events
;
2250 struct lttng_consumer_local_data
*ctx
= data
;
2253 rcu_register_thread();
2255 health_register(health_consumerd
, HEALTH_CONSUMERD_TYPE_METADATA
);
2257 health_code_update();
2259 DBG("Thread metadata poll started");
2261 /* Size is set to 1 for the consumer_metadata pipe */
2262 ret
= lttng_poll_create(&events
, 2, LTTNG_CLOEXEC
);
2264 ERR("Poll set creation failed");
2268 ret
= lttng_poll_add(&events
,
2269 lttng_pipe_get_readfd(ctx
->consumer_metadata_pipe
), LPOLLIN
);
2275 DBG("Metadata main loop started");
2278 health_code_update();
2280 /* Only the metadata pipe is set */
2281 if (LTTNG_POLL_GETNB(&events
) == 0 && consumer_quit
== 1) {
2282 err
= 0; /* All is OK */
2287 DBG("Metadata poll wait with %d fd(s)", LTTNG_POLL_GETNB(&events
));
2288 health_poll_entry();
2289 ret
= lttng_poll_wait(&events
, -1);
2291 DBG("Metadata event catched in thread");
2293 if (errno
== EINTR
) {
2294 ERR("Poll EINTR catched");
2302 /* From here, the event is a metadata wait fd */
2303 for (i
= 0; i
< nb_fd
; i
++) {
2304 health_code_update();
2306 revents
= LTTNG_POLL_GETEV(&events
, i
);
2307 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2309 if (pollfd
== lttng_pipe_get_readfd(ctx
->consumer_metadata_pipe
)) {
2310 if (revents
& (LPOLLERR
| LPOLLHUP
)) {
2311 DBG("Metadata thread pipe hung up");
2313 * Remove the pipe from the poll set and continue the loop
2314 * since their might be data to consume.
2316 lttng_poll_del(&events
,
2317 lttng_pipe_get_readfd(ctx
->consumer_metadata_pipe
));
2318 lttng_pipe_read_close(ctx
->consumer_metadata_pipe
);
2320 } else if (revents
& LPOLLIN
) {
2323 pipe_len
= lttng_pipe_read(ctx
->consumer_metadata_pipe
,
2324 &stream
, sizeof(stream
));
2325 if (pipe_len
< sizeof(stream
)) {
2326 PERROR("read metadata stream");
2328 * Continue here to handle the rest of the streams.
2333 /* A NULL stream means that the state has changed. */
2334 if (stream
== NULL
) {
2335 /* Check for deleted streams. */
2336 validate_endpoint_status_metadata_stream(&events
);
2340 DBG("Adding metadata stream %d to poll set",
2343 /* Add metadata stream to the global poll events list */
2344 lttng_poll_add(&events
, stream
->wait_fd
,
2345 LPOLLIN
| LPOLLPRI
);
2348 /* Handle other stream */
2354 uint64_t tmp_id
= (uint64_t) pollfd
;
2356 lttng_ht_lookup(metadata_ht
, &tmp_id
, &iter
);
2358 node
= lttng_ht_iter_get_node_u64(&iter
);
2361 stream
= caa_container_of(node
, struct lttng_consumer_stream
,
2364 /* Check for error event */
2365 if (revents
& (LPOLLERR
| LPOLLHUP
)) {
2366 DBG("Metadata fd %d is hup|err.", pollfd
);
2367 if (!stream
->hangup_flush_done
2368 && (consumer_data
.type
== LTTNG_CONSUMER32_UST
2369 || consumer_data
.type
== LTTNG_CONSUMER64_UST
)) {
2370 DBG("Attempting to flush and consume the UST buffers");
2371 lttng_ustconsumer_on_stream_hangup(stream
);
2373 /* We just flushed the stream now read it. */
2375 health_code_update();
2377 len
= ctx
->on_buffer_ready(stream
, ctx
);
2379 * We don't check the return value here since if we get
2380 * a negative len, it means an error occured thus we
2381 * simply remove it from the poll set and free the
2387 lttng_poll_del(&events
, stream
->wait_fd
);
2389 * This call update the channel states, closes file descriptors
2390 * and securely free the stream.
2392 consumer_del_metadata_stream(stream
, metadata_ht
);
2393 } else if (revents
& (LPOLLIN
| LPOLLPRI
)) {
2394 /* Get the data out of the metadata file descriptor */
2395 DBG("Metadata available on fd %d", pollfd
);
2396 assert(stream
->wait_fd
== pollfd
);
2399 health_code_update();
2401 len
= ctx
->on_buffer_ready(stream
, ctx
);
2403 * We don't check the return value here since if we get
2404 * a negative len, it means an error occured thus we
2405 * simply remove it from the poll set and free the
2410 /* It's ok to have an unavailable sub-buffer */
2411 if (len
< 0 && len
!= -EAGAIN
&& len
!= -ENODATA
) {
2412 /* Clean up stream from consumer and free it. */
2413 lttng_poll_del(&events
, stream
->wait_fd
);
2414 consumer_del_metadata_stream(stream
, metadata_ht
);
2418 /* Release RCU lock for the stream looked up */
2427 DBG("Metadata poll thread exiting");
2429 lttng_poll_clean(&events
);
2433 ERR("Health error occurred in %s", __func__
);
2435 health_unregister(health_consumerd
);
2436 rcu_unregister_thread();
2441 * This thread polls the fds in the set to consume the data and write
2442 * it to tracefile if necessary.
2444 void *consumer_thread_data_poll(void *data
)
2446 int num_rdy
, num_hup
, high_prio
, ret
, i
, err
= -1;
2447 struct pollfd
*pollfd
= NULL
;
2448 /* local view of the streams */
2449 struct lttng_consumer_stream
**local_stream
= NULL
, *new_stream
= NULL
;
2450 /* local view of consumer_data.fds_count */
2452 struct lttng_consumer_local_data
*ctx
= data
;
2455 rcu_register_thread();
2457 health_register(health_consumerd
, HEALTH_CONSUMERD_TYPE_DATA
);
2459 health_code_update();
2461 local_stream
= zmalloc(sizeof(struct lttng_consumer_stream
*));
2462 if (local_stream
== NULL
) {
2463 PERROR("local_stream malloc");
2468 health_code_update();
2474 * the fds set has been updated, we need to update our
2475 * local array as well
2477 pthread_mutex_lock(&consumer_data
.lock
);
2478 if (consumer_data
.need_update
) {
2483 local_stream
= NULL
;
2485 /* allocate for all fds + 1 for the consumer_data_pipe */
2486 pollfd
= zmalloc((consumer_data
.stream_count
+ 1) * sizeof(struct pollfd
));
2487 if (pollfd
== NULL
) {
2488 PERROR("pollfd malloc");
2489 pthread_mutex_unlock(&consumer_data
.lock
);
2493 /* allocate for all fds + 1 for the consumer_data_pipe */
2494 local_stream
= zmalloc((consumer_data
.stream_count
+ 1) *
2495 sizeof(struct lttng_consumer_stream
*));
2496 if (local_stream
== NULL
) {
2497 PERROR("local_stream malloc");
2498 pthread_mutex_unlock(&consumer_data
.lock
);
2501 ret
= update_poll_array(ctx
, &pollfd
, local_stream
,
2504 ERR("Error in allocating pollfd or local_outfds");
2505 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_POLL_ERROR
);
2506 pthread_mutex_unlock(&consumer_data
.lock
);
2510 consumer_data
.need_update
= 0;
2512 pthread_mutex_unlock(&consumer_data
.lock
);
2514 /* No FDs and consumer_quit, consumer_cleanup the thread */
2515 if (nb_fd
== 0 && consumer_quit
== 1) {
2516 err
= 0; /* All is OK */
2519 /* poll on the array of fds */
2521 DBG("polling on %d fd", nb_fd
+ 1);
2522 health_poll_entry();
2523 num_rdy
= poll(pollfd
, nb_fd
+ 1, -1);
2525 DBG("poll num_rdy : %d", num_rdy
);
2526 if (num_rdy
== -1) {
2528 * Restart interrupted system call.
2530 if (errno
== EINTR
) {
2533 PERROR("Poll error");
2534 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_POLL_ERROR
);
2536 } else if (num_rdy
== 0) {
2537 DBG("Polling thread timed out");
2542 * If the consumer_data_pipe triggered poll go directly to the
2543 * beginning of the loop to update the array. We want to prioritize
2544 * array update over low-priority reads.
2546 if (pollfd
[nb_fd
].revents
& (POLLIN
| POLLPRI
)) {
2547 ssize_t pipe_readlen
;
2549 DBG("consumer_data_pipe wake up");
2550 pipe_readlen
= lttng_pipe_read(ctx
->consumer_data_pipe
,
2551 &new_stream
, sizeof(new_stream
));
2552 if (pipe_readlen
< sizeof(new_stream
)) {
2553 PERROR("Consumer data pipe");
2554 /* Continue so we can at least handle the current stream(s). */
2559 * If the stream is NULL, just ignore it. It's also possible that
2560 * the sessiond poll thread changed the consumer_quit state and is
2561 * waking us up to test it.
2563 if (new_stream
== NULL
) {
2564 validate_endpoint_status_data_stream();
2568 /* Continue to update the local streams and handle prio ones */
2572 /* Take care of high priority channels first. */
2573 for (i
= 0; i
< nb_fd
; i
++) {
2574 health_code_update();
2576 if (local_stream
[i
] == NULL
) {
2579 if (pollfd
[i
].revents
& POLLPRI
) {
2580 DBG("Urgent read on fd %d", pollfd
[i
].fd
);
2582 len
= ctx
->on_buffer_ready(local_stream
[i
], ctx
);
2583 /* it's ok to have an unavailable sub-buffer */
2584 if (len
< 0 && len
!= -EAGAIN
&& len
!= -ENODATA
) {
2585 /* Clean the stream and free it. */
2586 consumer_del_stream(local_stream
[i
], data_ht
);
2587 local_stream
[i
] = NULL
;
2588 } else if (len
> 0) {
2589 local_stream
[i
]->data_read
= 1;
2595 * If we read high prio channel in this loop, try again
2596 * for more high prio data.
2602 /* Take care of low priority channels. */
2603 for (i
= 0; i
< nb_fd
; i
++) {
2604 health_code_update();
2606 if (local_stream
[i
] == NULL
) {
2609 if ((pollfd
[i
].revents
& POLLIN
) ||
2610 local_stream
[i
]->hangup_flush_done
) {
2611 DBG("Normal read on fd %d", pollfd
[i
].fd
);
2612 len
= ctx
->on_buffer_ready(local_stream
[i
], ctx
);
2613 /* it's ok to have an unavailable sub-buffer */
2614 if (len
< 0 && len
!= -EAGAIN
&& len
!= -ENODATA
) {
2615 /* Clean the stream and free it. */
2616 consumer_del_stream(local_stream
[i
], data_ht
);
2617 local_stream
[i
] = NULL
;
2618 } else if (len
> 0) {
2619 local_stream
[i
]->data_read
= 1;
2624 /* Handle hangup and errors */
2625 for (i
= 0; i
< nb_fd
; i
++) {
2626 health_code_update();
2628 if (local_stream
[i
] == NULL
) {
2631 if (!local_stream
[i
]->hangup_flush_done
2632 && (pollfd
[i
].revents
& (POLLHUP
| POLLERR
| POLLNVAL
))
2633 && (consumer_data
.type
== LTTNG_CONSUMER32_UST
2634 || consumer_data
.type
== LTTNG_CONSUMER64_UST
)) {
2635 DBG("fd %d is hup|err|nval. Attempting flush and read.",
2637 lttng_ustconsumer_on_stream_hangup(local_stream
[i
]);
2638 /* Attempt read again, for the data we just flushed. */
2639 local_stream
[i
]->data_read
= 1;
2642 * If the poll flag is HUP/ERR/NVAL and we have
2643 * read no data in this pass, we can remove the
2644 * stream from its hash table.
2646 if ((pollfd
[i
].revents
& POLLHUP
)) {
2647 DBG("Polling fd %d tells it has hung up.", pollfd
[i
].fd
);
2648 if (!local_stream
[i
]->data_read
) {
2649 consumer_del_stream(local_stream
[i
], data_ht
);
2650 local_stream
[i
] = NULL
;
2653 } else if (pollfd
[i
].revents
& POLLERR
) {
2654 ERR("Error returned in polling fd %d.", pollfd
[i
].fd
);
2655 if (!local_stream
[i
]->data_read
) {
2656 consumer_del_stream(local_stream
[i
], data_ht
);
2657 local_stream
[i
] = NULL
;
2660 } else if (pollfd
[i
].revents
& POLLNVAL
) {
2661 ERR("Polling fd %d tells fd is not open.", pollfd
[i
].fd
);
2662 if (!local_stream
[i
]->data_read
) {
2663 consumer_del_stream(local_stream
[i
], data_ht
);
2664 local_stream
[i
] = NULL
;
2668 if (local_stream
[i
] != NULL
) {
2669 local_stream
[i
]->data_read
= 0;
2676 DBG("polling thread exiting");
2681 * Close the write side of the pipe so epoll_wait() in
2682 * consumer_thread_metadata_poll can catch it. The thread is monitoring the
2683 * read side of the pipe. If we close them both, epoll_wait strangely does
2684 * not return and could create a endless wait period if the pipe is the
2685 * only tracked fd in the poll set. The thread will take care of closing
2688 (void) lttng_pipe_write_close(ctx
->consumer_metadata_pipe
);
2692 ERR("Health error occurred in %s", __func__
);
2694 health_unregister(health_consumerd
);
2696 rcu_unregister_thread();
2701 * Close wake-up end of each stream belonging to the channel. This will
2702 * allow the poll() on the stream read-side to detect when the
2703 * write-side (application) finally closes them.
2706 void consumer_close_channel_streams(struct lttng_consumer_channel
*channel
)
2708 struct lttng_ht
*ht
;
2709 struct lttng_consumer_stream
*stream
;
2710 struct lttng_ht_iter iter
;
2712 ht
= consumer_data
.stream_per_chan_id_ht
;
2715 cds_lfht_for_each_entry_duplicate(ht
->ht
,
2716 ht
->hash_fct(&channel
->key
, lttng_ht_seed
),
2717 ht
->match_fct
, &channel
->key
,
2718 &iter
.iter
, stream
, node_channel_id
.node
) {
2720 * Protect against teardown with mutex.
2722 pthread_mutex_lock(&stream
->lock
);
2723 if (cds_lfht_is_node_deleted(&stream
->node
.node
)) {
2726 switch (consumer_data
.type
) {
2727 case LTTNG_CONSUMER_KERNEL
:
2729 case LTTNG_CONSUMER32_UST
:
2730 case LTTNG_CONSUMER64_UST
:
2732 * Note: a mutex is taken internally within
2733 * liblttng-ust-ctl to protect timer wakeup_fd
2734 * use from concurrent close.
2736 lttng_ustconsumer_close_stream_wakeup(stream
);
2739 ERR("Unknown consumer_data type");
2743 pthread_mutex_unlock(&stream
->lock
);
2748 static void destroy_channel_ht(struct lttng_ht
*ht
)
2750 struct lttng_ht_iter iter
;
2751 struct lttng_consumer_channel
*channel
;
2759 cds_lfht_for_each_entry(ht
->ht
, &iter
.iter
, channel
, wait_fd_node
.node
) {
2760 ret
= lttng_ht_del(ht
, &iter
);
2765 lttng_ht_destroy(ht
);
2769 * This thread polls the channel fds to detect when they are being
2770 * closed. It closes all related streams if the channel is detected as
2771 * closed. It is currently only used as a shim layer for UST because the
2772 * consumerd needs to keep the per-stream wakeup end of pipes open for
2775 void *consumer_thread_channel_poll(void *data
)
2777 int ret
, i
, pollfd
, err
= -1;
2778 uint32_t revents
, nb_fd
;
2779 struct lttng_consumer_channel
*chan
= NULL
;
2780 struct lttng_ht_iter iter
;
2781 struct lttng_ht_node_u64
*node
;
2782 struct lttng_poll_event events
;
2783 struct lttng_consumer_local_data
*ctx
= data
;
2784 struct lttng_ht
*channel_ht
;
2786 rcu_register_thread();
2788 health_register(health_consumerd
, HEALTH_CONSUMERD_TYPE_CHANNEL
);
2790 health_code_update();
2792 channel_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
2794 /* ENOMEM at this point. Better to bail out. */
2798 DBG("Thread channel poll started");
2800 /* Size is set to 1 for the consumer_channel pipe */
2801 ret
= lttng_poll_create(&events
, 2, LTTNG_CLOEXEC
);
2803 ERR("Poll set creation failed");
2807 ret
= lttng_poll_add(&events
, ctx
->consumer_channel_pipe
[0], LPOLLIN
);
2813 DBG("Channel main loop started");
2816 health_code_update();
2818 /* Only the channel pipe is set */
2819 if (LTTNG_POLL_GETNB(&events
) == 0 && consumer_quit
== 1) {
2820 err
= 0; /* All is OK */
2825 DBG("Channel poll wait with %d fd(s)", LTTNG_POLL_GETNB(&events
));
2826 health_poll_entry();
2827 ret
= lttng_poll_wait(&events
, -1);
2829 DBG("Channel event catched in thread");
2831 if (errno
== EINTR
) {
2832 ERR("Poll EINTR catched");
2840 /* From here, the event is a channel wait fd */
2841 for (i
= 0; i
< nb_fd
; i
++) {
2842 health_code_update();
2844 revents
= LTTNG_POLL_GETEV(&events
, i
);
2845 pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2847 /* Just don't waste time if no returned events for the fd */
2851 if (pollfd
== ctx
->consumer_channel_pipe
[0]) {
2852 if (revents
& (LPOLLERR
| LPOLLHUP
)) {
2853 DBG("Channel thread pipe hung up");
2855 * Remove the pipe from the poll set and continue the loop
2856 * since their might be data to consume.
2858 lttng_poll_del(&events
, ctx
->consumer_channel_pipe
[0]);
2860 } else if (revents
& LPOLLIN
) {
2861 enum consumer_channel_action action
;
2864 ret
= read_channel_pipe(ctx
, &chan
, &key
, &action
);
2866 ERR("Error reading channel pipe");
2871 case CONSUMER_CHANNEL_ADD
:
2872 DBG("Adding channel %d to poll set",
2875 lttng_ht_node_init_u64(&chan
->wait_fd_node
,
2878 lttng_ht_add_unique_u64(channel_ht
,
2879 &chan
->wait_fd_node
);
2881 /* Add channel to the global poll events list */
2882 lttng_poll_add(&events
, chan
->wait_fd
,
2883 LPOLLIN
| LPOLLPRI
);
2885 case CONSUMER_CHANNEL_DEL
:
2887 struct lttng_consumer_stream
*stream
, *stmp
;
2890 chan
= consumer_find_channel(key
);
2893 ERR("UST consumer get channel key %" PRIu64
" not found for del channel", key
);
2896 lttng_poll_del(&events
, chan
->wait_fd
);
2897 iter
.iter
.node
= &chan
->wait_fd_node
.node
;
2898 ret
= lttng_ht_del(channel_ht
, &iter
);
2900 consumer_close_channel_streams(chan
);
2902 switch (consumer_data
.type
) {
2903 case LTTNG_CONSUMER_KERNEL
:
2905 case LTTNG_CONSUMER32_UST
:
2906 case LTTNG_CONSUMER64_UST
:
2907 /* Delete streams that might have been left in the stream list. */
2908 cds_list_for_each_entry_safe(stream
, stmp
, &chan
->streams
.head
,
2910 health_code_update();
2912 cds_list_del(&stream
->send_node
);
2913 lttng_ustconsumer_del_stream(stream
);
2914 uatomic_sub(&stream
->chan
->refcount
, 1);
2915 assert(&chan
->refcount
);
2920 ERR("Unknown consumer_data type");
2925 * Release our own refcount. Force channel deletion even if
2926 * streams were not initialized.
2928 if (!uatomic_sub_return(&chan
->refcount
, 1)) {
2929 consumer_del_channel(chan
);
2934 case CONSUMER_CHANNEL_QUIT
:
2936 * Remove the pipe from the poll set and continue the loop
2937 * since their might be data to consume.
2939 lttng_poll_del(&events
, ctx
->consumer_channel_pipe
[0]);
2942 ERR("Unknown action");
2947 /* Handle other stream */
2953 uint64_t tmp_id
= (uint64_t) pollfd
;
2955 lttng_ht_lookup(channel_ht
, &tmp_id
, &iter
);
2957 node
= lttng_ht_iter_get_node_u64(&iter
);
2960 chan
= caa_container_of(node
, struct lttng_consumer_channel
,
2963 /* Check for error event */
2964 if (revents
& (LPOLLERR
| LPOLLHUP
)) {
2965 DBG("Channel fd %d is hup|err.", pollfd
);
2967 lttng_poll_del(&events
, chan
->wait_fd
);
2968 ret
= lttng_ht_del(channel_ht
, &iter
);
2970 consumer_close_channel_streams(chan
);
2972 /* Release our own refcount */
2973 if (!uatomic_sub_return(&chan
->refcount
, 1)
2974 && !uatomic_read(&chan
->nb_init_stream_left
)) {
2975 consumer_del_channel(chan
);
2979 /* Release RCU lock for the channel looked up */
2987 lttng_poll_clean(&events
);
2989 destroy_channel_ht(channel_ht
);
2991 DBG("Channel poll thread exiting");
2994 ERR("Health error occurred in %s", __func__
);
2996 health_unregister(health_consumerd
);
2997 rcu_unregister_thread();
3001 static int set_metadata_socket(struct lttng_consumer_local_data
*ctx
,
3002 struct pollfd
*sockpoll
, int client_socket
)
3009 if (lttng_consumer_poll_socket(sockpoll
) < 0) {
3013 DBG("Metadata connection on client_socket");
3015 /* Blocking call, waiting for transmission */
3016 ctx
->consumer_metadata_socket
= lttcomm_accept_unix_sock(client_socket
);
3017 if (ctx
->consumer_metadata_socket
< 0) {
3018 WARN("On accept metadata");
3029 * This thread listens on the consumerd socket and receives the file
3030 * descriptors from the session daemon.
3032 void *consumer_thread_sessiond_poll(void *data
)
3034 int sock
= -1, client_socket
, ret
, err
= -1;
3036 * structure to poll for incoming data on communication socket avoids
3037 * making blocking sockets.
3039 struct pollfd consumer_sockpoll
[2];
3040 struct lttng_consumer_local_data
*ctx
= data
;
3042 rcu_register_thread();
3044 health_register(health_consumerd
, HEALTH_CONSUMERD_TYPE_SESSIOND
);
3046 health_code_update();
3048 DBG("Creating command socket %s", ctx
->consumer_command_sock_path
);
3049 unlink(ctx
->consumer_command_sock_path
);
3050 client_socket
= lttcomm_create_unix_sock(ctx
->consumer_command_sock_path
);
3051 if (client_socket
< 0) {
3052 ERR("Cannot create command socket");
3056 ret
= lttcomm_listen_unix_sock(client_socket
);
3061 DBG("Sending ready command to lttng-sessiond");
3062 ret
= lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_COMMAND_SOCK_READY
);
3063 /* return < 0 on error, but == 0 is not fatal */
3065 ERR("Error sending ready command to lttng-sessiond");
3069 /* prepare the FDs to poll : to client socket and the should_quit pipe */
3070 consumer_sockpoll
[0].fd
= ctx
->consumer_should_quit
[0];
3071 consumer_sockpoll
[0].events
= POLLIN
| POLLPRI
;
3072 consumer_sockpoll
[1].fd
= client_socket
;
3073 consumer_sockpoll
[1].events
= POLLIN
| POLLPRI
;
3075 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
3078 DBG("Connection on client_socket");
3080 /* Blocking call, waiting for transmission */
3081 sock
= lttcomm_accept_unix_sock(client_socket
);
3088 * Setup metadata socket which is the second socket connection on the
3089 * command unix socket.
3091 ret
= set_metadata_socket(ctx
, consumer_sockpoll
, client_socket
);
3096 /* This socket is not useful anymore. */
3097 ret
= close(client_socket
);
3099 PERROR("close client_socket");
3103 /* update the polling structure to poll on the established socket */
3104 consumer_sockpoll
[1].fd
= sock
;
3105 consumer_sockpoll
[1].events
= POLLIN
| POLLPRI
;
3108 health_code_update();
3110 health_poll_entry();
3111 ret
= lttng_consumer_poll_socket(consumer_sockpoll
);
3116 DBG("Incoming command on sock");
3117 ret
= lttng_consumer_recv_cmd(ctx
, sock
, consumer_sockpoll
);
3118 if (ret
== -ENOENT
) {
3119 DBG("Received STOP command");
3124 * This could simply be a session daemon quitting. Don't output
3127 DBG("Communication interrupted on command socket");
3131 if (consumer_quit
) {
3132 DBG("consumer_thread_receive_fds received quit from signal");
3133 err
= 0; /* All is OK */
3136 DBG("received command on sock");
3142 DBG("Consumer thread sessiond poll exiting");
3145 * Close metadata streams since the producer is the session daemon which
3148 * NOTE: for now, this only applies to the UST tracer.
3150 lttng_consumer_close_metadata();
3153 * when all fds have hung up, the polling thread
3159 * Notify the data poll thread to poll back again and test the
3160 * consumer_quit state that we just set so to quit gracefully.
3162 notify_thread_lttng_pipe(ctx
->consumer_data_pipe
);
3164 notify_channel_pipe(ctx
, NULL
, -1, CONSUMER_CHANNEL_QUIT
);
3166 notify_health_quit_pipe(health_quit_pipe
);
3168 /* Cleaning up possibly open sockets. */
3172 PERROR("close sock sessiond poll");
3175 if (client_socket
>= 0) {
3176 ret
= close(client_socket
);
3178 PERROR("close client_socket sessiond poll");
3184 ERR("Health error occurred in %s", __func__
);
3186 health_unregister(health_consumerd
);
3188 rcu_unregister_thread();
3192 ssize_t
lttng_consumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
3193 struct lttng_consumer_local_data
*ctx
)
3197 pthread_mutex_lock(&stream
->lock
);
3198 if (stream
->metadata_flag
) {
3199 pthread_mutex_lock(&stream
->metadata_rdv_lock
);
3202 switch (consumer_data
.type
) {
3203 case LTTNG_CONSUMER_KERNEL
:
3204 ret
= lttng_kconsumer_read_subbuffer(stream
, ctx
);
3206 case LTTNG_CONSUMER32_UST
:
3207 case LTTNG_CONSUMER64_UST
:
3208 ret
= lttng_ustconsumer_read_subbuffer(stream
, ctx
);
3211 ERR("Unknown consumer_data type");
3217 if (stream
->metadata_flag
) {
3218 pthread_cond_broadcast(&stream
->metadata_rdv
);
3219 pthread_mutex_unlock(&stream
->metadata_rdv_lock
);
3221 pthread_mutex_unlock(&stream
->lock
);
3225 int lttng_consumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
3227 switch (consumer_data
.type
) {
3228 case LTTNG_CONSUMER_KERNEL
:
3229 return lttng_kconsumer_on_recv_stream(stream
);
3230 case LTTNG_CONSUMER32_UST
:
3231 case LTTNG_CONSUMER64_UST
:
3232 return lttng_ustconsumer_on_recv_stream(stream
);
3234 ERR("Unknown consumer_data type");
3241 * Allocate and set consumer data hash tables.
3243 int lttng_consumer_init(void)
3245 consumer_data
.channel_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
3246 if (!consumer_data
.channel_ht
) {
3250 consumer_data
.relayd_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
3251 if (!consumer_data
.relayd_ht
) {
3255 consumer_data
.stream_list_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
3256 if (!consumer_data
.stream_list_ht
) {
3260 consumer_data
.stream_per_chan_id_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
3261 if (!consumer_data
.stream_per_chan_id_ht
) {
3265 data_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
3270 metadata_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_U64
);
3282 * Process the ADD_RELAYD command receive by a consumer.
3284 * This will create a relayd socket pair and add it to the relayd hash table.
3285 * The caller MUST acquire a RCU read side lock before calling it.
3287 int consumer_add_relayd_socket(uint64_t net_seq_idx
, int sock_type
,
3288 struct lttng_consumer_local_data
*ctx
, int sock
,
3289 struct pollfd
*consumer_sockpoll
,
3290 struct lttcomm_relayd_sock
*relayd_sock
, uint64_t sessiond_id
,
3291 uint64_t relayd_session_id
)
3293 int fd
= -1, ret
= -1, relayd_created
= 0;
3294 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
3295 struct consumer_relayd_sock_pair
*relayd
= NULL
;
3298 assert(relayd_sock
);
3300 DBG("Consumer adding relayd socket (idx: %" PRIu64
")", net_seq_idx
);
3302 /* Get relayd reference if exists. */
3303 relayd
= consumer_find_relayd(net_seq_idx
);
3304 if (relayd
== NULL
) {
3305 assert(sock_type
== LTTNG_STREAM_CONTROL
);
3306 /* Not found. Allocate one. */
3307 relayd
= consumer_allocate_relayd_sock_pair(net_seq_idx
);
3308 if (relayd
== NULL
) {
3310 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
3313 relayd
->sessiond_session_id
= sessiond_id
;
3318 * This code path MUST continue to the consumer send status message to
3319 * we can notify the session daemon and continue our work without
3320 * killing everything.
3324 * relayd key should never be found for control socket.
3326 assert(sock_type
!= LTTNG_STREAM_CONTROL
);
3329 /* First send a status message before receiving the fds. */
3330 ret
= consumer_send_status_msg(sock
, LTTCOMM_CONSUMERD_SUCCESS
);
3332 /* Somehow, the session daemon is not responding anymore. */
3333 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_FATAL
);
3334 goto error_nosignal
;
3337 /* Poll on consumer socket. */
3338 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
3339 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_POLL_ERROR
);
3341 goto error_nosignal
;
3344 /* Get relayd socket from session daemon */
3345 ret
= lttcomm_recv_fds_unix_sock(sock
, &fd
, 1);
3346 if (ret
!= sizeof(fd
)) {
3348 fd
= -1; /* Just in case it gets set with an invalid value. */
3351 * Failing to receive FDs might indicate a major problem such as
3352 * reaching a fd limit during the receive where the kernel returns a
3353 * MSG_CTRUNC and fails to cleanup the fd in the queue. Any case, we
3354 * don't take any chances and stop everything.
3356 * XXX: Feature request #558 will fix that and avoid this possible
3357 * issue when reaching the fd limit.
3359 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_FD
);
3360 ret_code
= LTTCOMM_CONSUMERD_ERROR_RECV_FD
;
3364 /* Copy socket information and received FD */
3365 switch (sock_type
) {
3366 case LTTNG_STREAM_CONTROL
:
3367 /* Copy received lttcomm socket */
3368 lttcomm_copy_sock(&relayd
->control_sock
.sock
, &relayd_sock
->sock
);
3369 ret
= lttcomm_create_sock(&relayd
->control_sock
.sock
);
3370 /* Handle create_sock error. */
3372 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
3376 * Close the socket created internally by
3377 * lttcomm_create_sock, so we can replace it by the one
3378 * received from sessiond.
3380 if (close(relayd
->control_sock
.sock
.fd
)) {
3384 /* Assign new file descriptor */
3385 relayd
->control_sock
.sock
.fd
= fd
;
3386 fd
= -1; /* For error path */
3387 /* Assign version values. */
3388 relayd
->control_sock
.major
= relayd_sock
->major
;
3389 relayd
->control_sock
.minor
= relayd_sock
->minor
;
3391 relayd
->relayd_session_id
= relayd_session_id
;
3394 case LTTNG_STREAM_DATA
:
3395 /* Copy received lttcomm socket */
3396 lttcomm_copy_sock(&relayd
->data_sock
.sock
, &relayd_sock
->sock
);
3397 ret
= lttcomm_create_sock(&relayd
->data_sock
.sock
);
3398 /* Handle create_sock error. */
3400 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
3404 * Close the socket created internally by
3405 * lttcomm_create_sock, so we can replace it by the one
3406 * received from sessiond.
3408 if (close(relayd
->data_sock
.sock
.fd
)) {
3412 /* Assign new file descriptor */
3413 relayd
->data_sock
.sock
.fd
= fd
;
3414 fd
= -1; /* for eventual error paths */
3415 /* Assign version values. */
3416 relayd
->data_sock
.major
= relayd_sock
->major
;
3417 relayd
->data_sock
.minor
= relayd_sock
->minor
;
3420 ERR("Unknown relayd socket type (%d)", sock_type
);
3422 ret_code
= LTTCOMM_CONSUMERD_FATAL
;
3426 DBG("Consumer %s socket created successfully with net idx %" PRIu64
" (fd: %d)",
3427 sock_type
== LTTNG_STREAM_CONTROL
? "control" : "data",
3428 relayd
->net_seq_idx
, fd
);
3430 /* We successfully added the socket. Send status back. */
3431 ret
= consumer_send_status_msg(sock
, ret_code
);
3433 /* Somehow, the session daemon is not responding anymore. */
3434 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_FATAL
);
3435 goto error_nosignal
;
3439 * Add relayd socket pair to consumer data hashtable. If object already
3440 * exists or on error, the function gracefully returns.
3448 if (consumer_send_status_msg(sock
, ret_code
) < 0) {
3449 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_FATAL
);
3453 /* Close received socket if valid. */
3456 PERROR("close received socket");
3460 if (relayd_created
) {
3468 * Try to lock the stream mutex.
3470 * On success, 1 is returned else 0 indicating that the mutex is NOT lock.
3472 static int stream_try_lock(struct lttng_consumer_stream
*stream
)
3479 * Try to lock the stream mutex. On failure, we know that the stream is
3480 * being used else where hence there is data still being extracted.
3482 ret
= pthread_mutex_trylock(&stream
->lock
);
3484 /* For both EBUSY and EINVAL error, the mutex is NOT locked. */
3496 * Search for a relayd associated to the session id and return the reference.
3498 * A rcu read side lock MUST be acquire before calling this function and locked
3499 * until the relayd object is no longer necessary.
3501 static struct consumer_relayd_sock_pair
*find_relayd_by_session_id(uint64_t id
)
3503 struct lttng_ht_iter iter
;
3504 struct consumer_relayd_sock_pair
*relayd
= NULL
;
3506 /* Iterate over all relayd since they are indexed by net_seq_idx. */
3507 cds_lfht_for_each_entry(consumer_data
.relayd_ht
->ht
, &iter
.iter
, relayd
,
3510 * Check by sessiond id which is unique here where the relayd session
3511 * id might not be when having multiple relayd.
3513 if (relayd
->sessiond_session_id
== id
) {
3514 /* Found the relayd. There can be only one per id. */
3526 * Check if for a given session id there is still data needed to be extract
3529 * Return 1 if data is pending or else 0 meaning ready to be read.
3531 int consumer_data_pending(uint64_t id
)
3534 struct lttng_ht_iter iter
;
3535 struct lttng_ht
*ht
;
3536 struct lttng_consumer_stream
*stream
;
3537 struct consumer_relayd_sock_pair
*relayd
= NULL
;
3538 int (*data_pending
)(struct lttng_consumer_stream
*);
3540 DBG("Consumer data pending command on session id %" PRIu64
, id
);
3543 pthread_mutex_lock(&consumer_data
.lock
);
3545 switch (consumer_data
.type
) {
3546 case LTTNG_CONSUMER_KERNEL
:
3547 data_pending
= lttng_kconsumer_data_pending
;
3549 case LTTNG_CONSUMER32_UST
:
3550 case LTTNG_CONSUMER64_UST
:
3551 data_pending
= lttng_ustconsumer_data_pending
;
3554 ERR("Unknown consumer data type");
3558 /* Ease our life a bit */
3559 ht
= consumer_data
.stream_list_ht
;
3561 relayd
= find_relayd_by_session_id(id
);
3563 /* Send init command for data pending. */
3564 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
3565 ret
= relayd_begin_data_pending(&relayd
->control_sock
,
3566 relayd
->relayd_session_id
);
3567 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
3569 /* Communication error thus the relayd so no data pending. */
3570 goto data_not_pending
;
3574 cds_lfht_for_each_entry_duplicate(ht
->ht
,
3575 ht
->hash_fct(&id
, lttng_ht_seed
),
3577 &iter
.iter
, stream
, node_session_id
.node
) {
3578 /* If this call fails, the stream is being used hence data pending. */
3579 ret
= stream_try_lock(stream
);
3585 * A removed node from the hash table indicates that the stream has
3586 * been deleted thus having a guarantee that the buffers are closed
3587 * on the consumer side. However, data can still be transmitted
3588 * over the network so don't skip the relayd check.
3590 ret
= cds_lfht_is_node_deleted(&stream
->node
.node
);
3593 * An empty output file is not valid. We need at least one packet
3594 * generated per stream, even if it contains no event, so it
3595 * contains at least one packet header.
3597 if (stream
->output_written
== 0) {
3598 pthread_mutex_unlock(&stream
->lock
);
3601 /* Check the stream if there is data in the buffers. */
3602 ret
= data_pending(stream
);
3604 pthread_mutex_unlock(&stream
->lock
);
3611 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
3612 if (stream
->metadata_flag
) {
3613 ret
= relayd_quiescent_control(&relayd
->control_sock
,
3614 stream
->relayd_stream_id
);
3616 ret
= relayd_data_pending(&relayd
->control_sock
,
3617 stream
->relayd_stream_id
,
3618 stream
->next_net_seq_num
- 1);
3620 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
3622 pthread_mutex_unlock(&stream
->lock
);
3626 pthread_mutex_unlock(&stream
->lock
);
3630 unsigned int is_data_inflight
= 0;
3632 /* Send init command for data pending. */
3633 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
3634 ret
= relayd_end_data_pending(&relayd
->control_sock
,
3635 relayd
->relayd_session_id
, &is_data_inflight
);
3636 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
3638 goto data_not_pending
;
3640 if (is_data_inflight
) {
3646 * Finding _no_ node in the hash table and no inflight data means that the
3647 * stream(s) have been removed thus data is guaranteed to be available for
3648 * analysis from the trace files.
3652 /* Data is available to be read by a viewer. */
3653 pthread_mutex_unlock(&consumer_data
.lock
);
3658 /* Data is still being extracted from buffers. */
3659 pthread_mutex_unlock(&consumer_data
.lock
);
3665 * Send a ret code status message to the sessiond daemon.
3667 * Return the sendmsg() return value.
3669 int consumer_send_status_msg(int sock
, int ret_code
)
3671 struct lttcomm_consumer_status_msg msg
;
3673 msg
.ret_code
= ret_code
;
3675 return lttcomm_send_unix_sock(sock
, &msg
, sizeof(msg
));
3679 * Send a channel status message to the sessiond daemon.
3681 * Return the sendmsg() return value.
3683 int consumer_send_status_channel(int sock
,
3684 struct lttng_consumer_channel
*channel
)
3686 struct lttcomm_consumer_status_channel msg
;
3691 msg
.ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
3693 msg
.ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
3694 msg
.key
= channel
->key
;
3695 msg
.stream_count
= channel
->streams
.count
;
3698 return lttcomm_send_unix_sock(sock
, &msg
, sizeof(msg
));
3702 * Using a maximum stream size with the produced and consumed position of a
3703 * stream, computes the new consumed position to be as close as possible to the
3704 * maximum possible stream size.
3706 * If maximum stream size is lower than the possible buffer size (produced -
3707 * consumed), the consumed_pos given is returned untouched else the new value
3710 unsigned long consumer_get_consumed_maxsize(unsigned long consumed_pos
,
3711 unsigned long produced_pos
, uint64_t max_stream_size
)
3713 if (max_stream_size
&& max_stream_size
< (produced_pos
- consumed_pos
)) {
3714 /* Offset from the produced position to get the latest buffers. */
3715 return produced_pos
- max_stream_size
;
3718 return consumed_pos
;