2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 #include <lttng/ust-ctl.h>
27 #include <sys/socket.h>
29 #include <sys/types.h>
32 #include <urcu/list.h>
35 #include <common/common.h>
36 #include <common/sessiond-comm/sessiond-comm.h>
37 #include <common/relayd/relayd.h>
38 #include <common/compat/fcntl.h>
39 #include <common/consumer-metadata-cache.h>
40 #include <common/consumer-timer.h>
41 #include <common/utils.h>
43 #include "ust-consumer.h"
45 extern struct lttng_consumer_global_data consumer_data
;
46 extern int consumer_poll_timeout
;
47 extern volatile int consumer_quit
;
50 * Free channel object and all streams associated with it. This MUST be used
51 * only and only if the channel has _NEVER_ been added to the global channel
54 static void destroy_channel(struct lttng_consumer_channel
*channel
)
56 struct lttng_consumer_stream
*stream
, *stmp
;
60 DBG("UST consumer cleaning stream list");
62 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
64 cds_list_del(&stream
->send_node
);
65 ustctl_destroy_stream(stream
->ustream
);
70 * If a channel is available meaning that was created before the streams
74 lttng_ustconsumer_del_channel(channel
);
80 * Add channel to internal consumer state.
82 * Returns 0 on success or else a negative value.
84 static int add_channel(struct lttng_consumer_channel
*channel
,
85 struct lttng_consumer_local_data
*ctx
)
92 if (ctx
->on_recv_channel
!= NULL
) {
93 ret
= ctx
->on_recv_channel(channel
);
95 ret
= consumer_add_channel(channel
, ctx
);
97 /* Most likely an ENOMEM. */
98 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
102 ret
= consumer_add_channel(channel
, ctx
);
105 DBG("UST consumer channel added (key: %" PRIu64
")", channel
->key
);
112 * Allocate and return a consumer channel object.
114 static struct lttng_consumer_channel
*allocate_channel(uint64_t session_id
,
115 const char *pathname
, const char *name
, uid_t uid
, gid_t gid
,
116 int relayd_id
, uint64_t key
, enum lttng_event_output output
,
117 uint64_t tracefile_size
, uint64_t tracefile_count
,
118 unsigned int monitor
)
123 return consumer_allocate_channel(key
, session_id
, pathname
, name
, uid
, gid
,
124 relayd_id
, output
, tracefile_size
, tracefile_count
, monitor
);
128 * Allocate and return a consumer stream object. If _alloc_ret is not NULL, the
129 * error value if applicable is set in it else it is kept untouched.
131 * Return NULL on error else the newly allocated stream object.
133 static struct lttng_consumer_stream
*allocate_stream(int cpu
, int key
,
134 struct lttng_consumer_channel
*channel
,
135 struct lttng_consumer_local_data
*ctx
, int *_alloc_ret
)
138 struct lttng_consumer_stream
*stream
= NULL
;
143 stream
= consumer_allocate_stream(channel
->key
,
145 LTTNG_CONSUMER_ACTIVE_STREAM
,
154 if (stream
== NULL
) {
158 * We could not find the channel. Can happen if cpu hotplug
159 * happens while tearing down.
161 DBG3("Could not find channel");
166 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
172 stream
->chan
= channel
;
176 *_alloc_ret
= alloc_ret
;
182 * Send the given stream pointer to the corresponding thread.
184 * Returns 0 on success else a negative value.
186 static int send_stream_to_thread(struct lttng_consumer_stream
*stream
,
187 struct lttng_consumer_local_data
*ctx
)
190 struct lttng_pipe
*stream_pipe
;
192 /* Get the right pipe where the stream will be sent. */
193 if (stream
->metadata_flag
) {
194 stream_pipe
= ctx
->consumer_metadata_pipe
;
196 stream_pipe
= ctx
->consumer_data_pipe
;
199 ret
= lttng_pipe_write(stream_pipe
, &stream
, sizeof(stream
));
201 ERR("Consumer write %s stream to pipe %d",
202 stream
->metadata_flag
? "metadata" : "data",
203 lttng_pipe_get_writefd(stream_pipe
));
210 * Search for a relayd object related to the stream. If found, send the stream
213 * On success, returns 0 else a negative value.
215 static int send_stream_to_relayd(struct lttng_consumer_stream
*stream
)
218 struct consumer_relayd_sock_pair
*relayd
;
222 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
223 if (relayd
!= NULL
) {
224 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
225 /* Add stream on the relayd */
226 ret
= relayd_add_stream(&relayd
->control_sock
, stream
->name
,
227 stream
->chan
->pathname
, &stream
->relayd_stream_id
,
228 stream
->chan
->tracefile_size
,
229 stream
->chan
->tracefile_count
);
230 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
234 } else if (stream
->net_seq_idx
!= (uint64_t) -1ULL) {
235 ERR("Network sequence index %" PRIu64
" unknown. Not adding stream.",
236 stream
->net_seq_idx
);
246 * Create streams for the given channel using liblttng-ust-ctl.
248 * Return 0 on success else a negative value.
250 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
251 struct lttng_consumer_local_data
*ctx
)
254 struct ustctl_consumer_stream
*ustream
;
255 struct lttng_consumer_stream
*stream
;
261 * While a stream is available from ustctl. When NULL is returned, we've
262 * reached the end of the possible stream for the channel.
264 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
267 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
269 /* Allocate consumer stream object. */
270 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
274 stream
->ustream
= ustream
;
276 * Store it so we can save multiple function calls afterwards since
277 * this value is used heavily in the stream threads. This is UST
278 * specific so this is why it's done after allocation.
280 stream
->wait_fd
= wait_fd
;
283 * Increment channel refcount since the channel reference has now been
284 * assigned in the allocation process above.
286 uatomic_inc(&stream
->chan
->refcount
);
289 * Order is important this is why a list is used. On error, the caller
290 * should clean this list.
292 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
294 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
295 &stream
->max_sb_size
);
297 ERR("ustctl_get_max_subbuf_size failed for stream %s",
302 /* Do actions once stream has been received. */
303 if (ctx
->on_recv_stream
) {
304 ret
= ctx
->on_recv_stream(stream
);
310 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
311 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
313 /* Set next CPU stream. */
314 channel
->streams
.count
= ++cpu
;
316 /* Keep stream reference when creating metadata. */
317 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
318 channel
->metadata_stream
= stream
;
330 * Create an UST channel with the given attributes and send it to the session
331 * daemon using the ust ctl API.
333 * Return 0 on success or else a negative value.
335 static int create_ust_channel(struct ustctl_consumer_channel_attr
*attr
,
336 struct ustctl_consumer_channel
**chanp
)
339 struct ustctl_consumer_channel
*channel
;
344 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
345 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
346 "switch_timer_interval: %u, read_timer_interval: %u, "
347 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
348 attr
->num_subbuf
, attr
->switch_timer_interval
,
349 attr
->read_timer_interval
, attr
->output
, attr
->type
);
351 channel
= ustctl_create_channel(attr
);
366 * Send a single given stream to the session daemon using the sock.
368 * Return 0 on success else a negative value.
370 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
377 DBG2("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
379 /* Send stream to session daemon. */
380 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
390 * Send channel to sessiond.
392 * Return 0 on success or else a negative value.
394 static int send_sessiond_channel(int sock
,
395 struct lttng_consumer_channel
*channel
,
396 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
398 int ret
, ret_code
= LTTNG_OK
;
399 struct lttng_consumer_stream
*stream
;
405 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
407 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
408 /* Try to send the stream to the relayd if one is available. */
409 ret
= send_stream_to_relayd(stream
);
412 * Flag that the relayd was the problem here probably due to a
413 * communicaton error on the socket.
418 ret_code
= LTTNG_ERR_RELAYD_CONNECT_FAIL
;
422 /* Inform sessiond that we are about to send channel and streams. */
423 ret
= consumer_send_status_msg(sock
, ret_code
);
424 if (ret
< 0 || ret_code
!= LTTNG_OK
) {
426 * Either the session daemon is not responding or the relayd died so we
432 /* Send channel to sessiond. */
433 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
438 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
443 /* The channel was sent successfully to the sessiond at this point. */
444 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
445 /* Send stream to session daemon. */
446 ret
= send_sessiond_stream(sock
, stream
);
452 /* Tell sessiond there is no more stream. */
453 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
458 DBG("UST consumer NULL stream sent to sessiond");
463 if (ret_code
!= LTTNG_OK
) {
470 * Creates a channel and streams and add the channel it to the channel internal
471 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
474 * Return 0 on success or else, a negative value is returned and the channel
475 * MUST be destroyed by consumer_del_channel().
477 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
478 struct lttng_consumer_channel
*channel
,
479 struct ustctl_consumer_channel_attr
*attr
)
488 * This value is still used by the kernel consumer since for the kernel,
489 * the stream ownership is not IN the consumer so we need to have the
490 * number of left stream that needs to be initialized so we can know when
491 * to delete the channel (see consumer.c).
493 * As for the user space tracer now, the consumer creates and sends the
494 * stream to the session daemon which only sends them to the application
495 * once every stream of a channel is received making this value useless
496 * because we they will be added to the poll thread before the application
497 * receives them. This ensures that a stream can not hang up during
498 * initilization of a channel.
500 channel
->nb_init_stream_left
= 0;
502 /* The reply msg status is handled in the following call. */
503 ret
= create_ust_channel(attr
, &channel
->uchan
);
508 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
510 /* Open all streams for this channel. */
511 ret
= create_ust_streams(channel
, ctx
);
521 * Send all stream of a channel to the right thread handling it.
523 * On error, return a negative value else 0 on success.
525 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
526 struct lttng_consumer_local_data
*ctx
)
529 struct lttng_consumer_stream
*stream
, *stmp
;
534 /* Send streams to the corresponding thread. */
535 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
537 /* Sending the stream to the thread. */
538 ret
= send_stream_to_thread(stream
, ctx
);
541 * If we are unable to send the stream to the thread, there is
542 * a big problem so just stop everything.
547 /* Remove node from the channel stream list. */
548 cds_list_del(&stream
->send_node
);
556 * Write metadata to the given channel using ustctl to convert the string to
558 * Called only from consumer_metadata_cache_write.
559 * The metadata cache lock MUST be acquired to write in the cache.
561 * Return 0 on success else a negative value.
563 int lttng_ustconsumer_push_metadata(struct lttng_consumer_channel
*metadata
,
564 const char *metadata_str
, uint64_t target_offset
, uint64_t len
)
569 assert(metadata_str
);
571 DBG("UST consumer writing metadata to channel %s", metadata
->name
);
573 if (!metadata
->metadata_stream
) {
578 assert(target_offset
<= metadata
->metadata_cache
->max_offset
);
579 ret
= ustctl_write_metadata_to_channel(metadata
->uchan
,
580 metadata_str
+ target_offset
, len
);
582 ERR("ustctl write metadata fail with ret %d, len %" PRIu64
, ret
, len
);
586 ustctl_flush_buffer(metadata
->metadata_stream
->ustream
, 1);
593 * Flush channel's streams using the given key to retrieve the channel.
595 * Return 0 on success else an LTTng error code.
597 static int flush_channel(uint64_t chan_key
)
600 struct lttng_consumer_channel
*channel
;
601 struct lttng_consumer_stream
*stream
;
603 struct lttng_ht_iter iter
;
605 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
608 channel
= consumer_find_channel(chan_key
);
610 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
611 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
615 ht
= consumer_data
.stream_per_chan_id_ht
;
617 /* For each stream of the channel id, flush it. */
618 cds_lfht_for_each_entry_duplicate(ht
->ht
,
619 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
620 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
621 ustctl_flush_buffer(stream
->ustream
, 1);
629 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
630 * RCU read side lock MUST be acquired before calling this function.
632 * Return 0 on success else an LTTng error code.
634 static int close_metadata(uint64_t chan_key
)
637 struct lttng_consumer_channel
*channel
;
639 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
641 channel
= consumer_find_channel(chan_key
);
644 * This is possible if the metadata thread has issue a delete because
645 * the endpoint point of the stream hung up. There is no way the
646 * session daemon can know about it thus use a DBG instead of an actual
649 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
650 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
654 pthread_mutex_lock(&consumer_data
.lock
);
656 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
660 if (channel
->switch_timer_enabled
== 1) {
661 DBG("Deleting timer on metadata channel");
662 consumer_timer_switch_stop(channel
);
665 if (channel
->metadata_stream
) {
666 ret
= ustctl_stream_close_wakeup_fd(channel
->metadata_stream
->ustream
);
668 ERR("UST consumer unable to close fd of metadata (ret: %d)", ret
);
669 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
675 pthread_mutex_unlock(&consumer_data
.lock
);
681 * RCU read side lock MUST be acquired before calling this function.
683 * Return 0 on success else an LTTng error code.
685 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
688 struct lttng_consumer_channel
*metadata
;
690 DBG("UST consumer setup metadata key %" PRIu64
, key
);
692 metadata
= consumer_find_channel(key
);
694 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
695 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
700 * Send metadata stream to relayd if one available. Availability is
701 * known if the stream is still in the list of the channel.
703 if (cds_list_empty(&metadata
->streams
.head
)) {
704 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
705 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
709 /* Send metadata stream to relayd if needed. */
710 ret
= send_stream_to_relayd(metadata
->metadata_stream
);
712 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
716 ret
= send_streams_to_thread(metadata
, ctx
);
719 * If we are unable to send the stream to the thread, there is
720 * a big problem so just stop everything.
722 ret
= LTTCOMM_CONSUMERD_FATAL
;
725 /* List MUST be empty after or else it could be reused. */
726 assert(cds_list_empty(&metadata
->streams
.head
));
732 * Delete metadata channel on error. At this point, the metadata stream can
733 * NOT be monitored by the metadata thread thus having the guarantee that
734 * the stream is still in the local stream list of the channel. This call
735 * will make sure to clean that list.
737 consumer_del_channel(metadata
);
743 * Receive the metadata updates from the sessiond.
745 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
746 uint64_t len
, struct lttng_consumer_channel
*channel
)
748 int ret
, ret_code
= LTTNG_OK
;
751 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
753 metadata_str
= zmalloc(len
* sizeof(char));
755 PERROR("zmalloc metadata string");
756 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
760 /* Receive metadata string. */
761 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
763 /* Session daemon is dead so return gracefully. */
769 * XXX: The consumer data lock is acquired before calling metadata cache
770 * write which calls push metadata that MUST be protected by the consumer
771 * lock in order to be able to check the validity of the metadata stream of
774 * Note that this will be subject to change to better fine grained locking
775 * and ultimately try to get rid of this global consumer data lock.
777 pthread_mutex_lock(&consumer_data
.lock
);
779 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
780 ret
= consumer_metadata_cache_write(channel
, offset
, len
, metadata_str
);
782 /* Unable to handle metadata. Notify session daemon. */
783 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
785 * Skip metadata flush on write error since the offset and len might
786 * not have been updated which could create an infinite loop below when
787 * waiting for the metadata cache to be flushed.
789 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
790 pthread_mutex_unlock(&consumer_data
.lock
);
793 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
794 pthread_mutex_unlock(&consumer_data
.lock
);
796 while (consumer_metadata_cache_flushed(channel
, offset
+ len
)) {
797 DBG("Waiting for metadata to be flushed");
798 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
808 * Receive command from session daemon and process it.
810 * Return 1 on success else a negative value or 0.
812 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
813 int sock
, struct pollfd
*consumer_sockpoll
)
816 enum lttng_error_code ret_code
= LTTNG_OK
;
817 struct lttcomm_consumer_msg msg
;
818 struct lttng_consumer_channel
*channel
= NULL
;
820 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
821 if (ret
!= sizeof(msg
)) {
822 DBG("Consumer received unexpected message size %zd (expects %zu)",
824 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
826 * The ret value might 0 meaning an orderly shutdown but this is ok
827 * since the caller handles this.
834 if (msg
.cmd_type
== LTTNG_CONSUMER_STOP
) {
836 * Notify the session daemon that the command is completed.
838 * On transport layer error, the function call will print an error
839 * message so handling the returned code is a bit useless since we
840 * return an error code anyway.
842 (void) consumer_send_status_msg(sock
, ret_code
);
846 /* relayd needs RCU read-side lock */
849 switch (msg
.cmd_type
) {
850 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
852 /* Session daemon status message are handled in the following call. */
853 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
854 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
855 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
);
858 case LTTNG_CONSUMER_DESTROY_RELAYD
:
860 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
861 struct consumer_relayd_sock_pair
*relayd
;
863 DBG("UST consumer destroying relayd %" PRIu64
, index
);
865 /* Get relayd reference if exists. */
866 relayd
= consumer_find_relayd(index
);
867 if (relayd
== NULL
) {
868 DBG("Unable to find relayd %" PRIu64
, index
);
869 ret_code
= LTTNG_ERR_NO_CONSUMER
;
873 * Each relayd socket pair has a refcount of stream attached to it
874 * which tells if the relayd is still active or not depending on the
877 * This will set the destroy flag of the relayd object and destroy it
878 * if the refcount reaches zero when called.
880 * The destroy can happen either here or when a stream fd hangs up.
883 consumer_flag_relayd_for_destroy(relayd
);
886 goto end_msg_sessiond
;
888 case LTTNG_CONSUMER_UPDATE_STREAM
:
893 case LTTNG_CONSUMER_DATA_PENDING
:
895 int ret
, is_data_pending
;
896 uint64_t id
= msg
.u
.data_pending
.session_id
;
898 DBG("UST consumer data pending command for id %" PRIu64
, id
);
900 is_data_pending
= consumer_data_pending(id
);
902 /* Send back returned value to session daemon */
903 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
904 sizeof(is_data_pending
));
906 DBG("Error when sending the data pending ret code: %d", ret
);
911 * No need to send back a status message since the data pending
912 * returned value is the response.
916 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
919 struct ustctl_consumer_channel_attr attr
;
921 /* Create a plain object and reserve a channel key. */
922 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
923 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
924 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
925 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
926 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
927 msg
.u
.ask_channel
.tracefile_size
,
928 msg
.u
.ask_channel
.tracefile_count
,
929 msg
.u
.ask_channel
.monitor
);
931 goto end_channel_error
;
934 /* Build channel attributes from received message. */
935 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
936 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
937 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
938 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
939 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
940 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
941 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
943 /* Translate the event output type to UST. */
944 switch (channel
->output
) {
945 case LTTNG_EVENT_SPLICE
:
946 /* Splice not supported so fallback on mmap(). */
947 case LTTNG_EVENT_MMAP
:
949 attr
.output
= CONSUMER_CHANNEL_MMAP
;
953 /* Translate and save channel type. */
954 switch (msg
.u
.ask_channel
.type
) {
955 case LTTNG_UST_CHAN_PER_CPU
:
956 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
957 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
959 * Set refcount to 1 for owner. Below, we will
960 * pass ownership to the
961 * consumer_thread_channel_poll() thread.
963 channel
->refcount
= 1;
965 case LTTNG_UST_CHAN_METADATA
:
966 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
967 attr
.type
= LTTNG_UST_CHAN_METADATA
;
974 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
976 goto end_channel_error
;
979 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
980 ret
= consumer_metadata_cache_allocate(channel
);
982 ERR("Allocating metadata cache");
983 goto end_channel_error
;
985 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
986 attr
.switch_timer_interval
= 0;
990 * Add the channel to the internal state AFTER all streams were created
991 * and successfully sent to session daemon. This way, all streams must
992 * be ready before this channel is visible to the threads.
993 * If add_channel succeeds, ownership of the channel is
994 * passed to consumer_thread_channel_poll().
996 ret
= add_channel(channel
, ctx
);
998 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
999 if (channel
->switch_timer_enabled
== 1) {
1000 consumer_timer_switch_stop(channel
);
1002 consumer_metadata_cache_destroy(channel
);
1004 goto end_channel_error
;
1008 * Channel and streams are now created. Inform the session daemon that
1009 * everything went well and should wait to receive the channel and
1010 * streams with ustctl API.
1012 ret
= consumer_send_status_channel(sock
, channel
);
1015 * There is probably a problem on the socket.
1022 case LTTNG_CONSUMER_GET_CHANNEL
:
1024 int ret
, relayd_err
= 0;
1025 uint64_t key
= msg
.u
.get_channel
.key
;
1026 struct lttng_consumer_channel
*channel
;
1028 channel
= consumer_find_channel(key
);
1030 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1031 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
1032 goto end_msg_sessiond
;
1035 /* Send everything to sessiond. */
1036 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1040 * We were unable to send to the relayd the stream so avoid
1041 * sending back a fatal error to the thread since this is OK
1042 * and the consumer can continue its work. The above call
1043 * has sent the error status message to the sessiond.
1048 * The communicaton was broken hence there is a bad state between
1049 * the consumer and sessiond so stop everything.
1054 ret
= send_streams_to_thread(channel
, ctx
);
1057 * If we are unable to send the stream to the thread, there is
1058 * a big problem so just stop everything.
1062 /* List MUST be empty after or else it could be reused. */
1063 assert(cds_list_empty(&channel
->streams
.head
));
1065 goto end_msg_sessiond
;
1067 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1069 uint64_t key
= msg
.u
.destroy_channel
.key
;
1072 * Only called if streams have not been sent to stream
1073 * manager thread. However, channel has been sent to
1074 * channel manager thread.
1076 notify_thread_del_channel(ctx
, key
);
1077 goto end_msg_sessiond
;
1079 case LTTNG_CONSUMER_CLOSE_METADATA
:
1083 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1088 goto end_msg_sessiond
;
1090 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1094 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1099 goto end_msg_sessiond
;
1101 case LTTNG_CONSUMER_PUSH_METADATA
:
1104 uint64_t len
= msg
.u
.push_metadata
.len
;
1105 uint64_t key
= msg
.u
.push_metadata
.key
;
1106 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1107 struct lttng_consumer_channel
*channel
;
1109 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1112 channel
= consumer_find_channel(key
);
1114 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
1115 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
1116 goto end_msg_sessiond
;
1119 /* Tell session daemon we are ready to receive the metadata. */
1120 ret
= consumer_send_status_msg(sock
, LTTNG_OK
);
1122 /* Somehow, the session daemon is not responding anymore. */
1126 /* Wait for more data. */
1127 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
1131 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1134 /* error receiving from sessiond */
1138 goto end_msg_sessiond
;
1141 case LTTNG_CONSUMER_SETUP_METADATA
:
1145 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1149 goto end_msg_sessiond
;
1151 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1153 ret
= consumer_send_status_msg(sock
, ret_code
);
1155 /* Somehow, the session daemon is not responding anymore. */
1168 * Return 1 to indicate success since the 0 value can be a socket
1169 * shutdown during the recv() or send() call.
1175 * The returned value here is not useful since either way we'll return 1 to
1176 * the caller because the session daemon socket management is done
1177 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1179 ret
= consumer_send_status_msg(sock
, ret_code
);
1188 * Free channel here since no one has a reference to it. We don't
1189 * free after that because a stream can store this pointer.
1191 destroy_channel(channel
);
1193 /* We have to send a status channel message indicating an error. */
1194 ret
= consumer_send_status_channel(sock
, NULL
);
1196 /* Stop everything if session daemon can not be notified. */
1203 /* This will issue a consumer stop. */
1208 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1209 * compiled out, we isolate it in this library.
1211 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1215 assert(stream
->ustream
);
1217 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1221 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1222 * compiled out, we isolate it in this library.
1224 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1227 assert(stream
->ustream
);
1229 return ustctl_get_mmap_base(stream
->ustream
);
1233 * Take a snapshot for a specific fd
1235 * Returns 0 on success, < 0 on error
1237 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1240 assert(stream
->ustream
);
1242 return ustctl_snapshot(stream
->ustream
);
1246 * Get the produced position
1248 * Returns 0 on success, < 0 on error
1250 int lttng_ustconsumer_get_produced_snapshot(
1251 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1254 assert(stream
->ustream
);
1257 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1261 * Called when the stream signal the consumer that it has hang up.
1263 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1266 assert(stream
->ustream
);
1268 ustctl_flush_buffer(stream
->ustream
, 0);
1269 stream
->hangup_flush_done
= 1;
1272 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1275 assert(chan
->uchan
);
1277 if (chan
->switch_timer_enabled
== 1) {
1278 consumer_timer_switch_stop(chan
);
1280 consumer_metadata_cache_destroy(chan
);
1281 ustctl_destroy_channel(chan
->uchan
);
1284 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
1287 assert(stream
->ustream
);
1289 if (stream
->chan
->switch_timer_enabled
== 1) {
1290 consumer_timer_switch_stop(stream
->chan
);
1292 ustctl_destroy_stream(stream
->ustream
);
1295 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
1296 struct lttng_consumer_local_data
*ctx
)
1298 unsigned long len
, subbuf_size
, padding
;
1302 struct ustctl_consumer_stream
*ustream
;
1305 assert(stream
->ustream
);
1308 DBG2("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
1311 /* Ease our life for what's next. */
1312 ustream
= stream
->ustream
;
1314 /* We can consume the 1 byte written into the wait_fd by UST */
1315 if (!stream
->hangup_flush_done
) {
1319 readlen
= read(stream
->wait_fd
, &dummy
, 1);
1320 } while (readlen
== -1 && errno
== EINTR
);
1321 if (readlen
== -1) {
1327 /* Get the next subbuffer */
1328 err
= ustctl_get_next_subbuf(ustream
);
1330 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
1332 * This is a debug message even for single-threaded consumer,
1333 * because poll() have more relaxed criterions than get subbuf,
1334 * so get_subbuf may fail for short race windows where poll()
1335 * would issue wakeups.
1337 DBG("Reserving sub buffer failed (everything is normal, "
1338 "it is due to concurrency) [ret: %d]", err
);
1341 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
1342 /* Get the full padded subbuffer size */
1343 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
1346 /* Get subbuffer data size (without padding) */
1347 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
1350 /* Make sure we don't get a subbuffer size bigger than the padded */
1351 assert(len
>= subbuf_size
);
1353 padding
= len
- subbuf_size
;
1354 /* write the subbuffer to the tracefile */
1355 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
);
1357 * The mmap operation should write subbuf_size amount of data when network
1358 * streaming or the full padding (len) size when we are _not_ streaming.
1360 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
1361 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
1363 * Display the error but continue processing to try to release the
1364 * subbuffer. This is a DBG statement since any unexpected kill or
1365 * signal, the application gets unregistered, relayd gets closed or
1366 * anything that affects the buffer lifetime will trigger this error.
1367 * So, for the sake of the user, don't print this error since it can
1368 * happen and it is OK with the code flow.
1370 DBG("Error writing to tracefile "
1371 "(ret: %ld != len: %lu != subbuf_size: %lu)",
1372 ret
, len
, subbuf_size
);
1374 err
= ustctl_put_next_subbuf(ustream
);
1382 * Called when a stream is created.
1384 * Return 0 on success or else a negative value.
1386 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
1390 /* Don't create anything if this is set for streaming. */
1391 if (stream
->net_seq_idx
== (uint64_t) -1ULL) {
1392 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
1393 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
1394 stream
->uid
, stream
->gid
);
1398 stream
->out_fd
= ret
;
1399 stream
->tracefile_size_current
= 0;
1408 * Check if data is still being extracted from the buffers for a specific
1409 * stream. Consumer data lock MUST be acquired before calling this function
1410 * and the stream lock.
1412 * Return 1 if the traced data are still getting read else 0 meaning that the
1413 * data is available for trace viewer reading.
1415 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
1420 assert(stream
->ustream
);
1422 DBG("UST consumer checking data pending");
1424 ret
= ustctl_get_next_subbuf(stream
->ustream
);
1426 /* There is still data so let's put back this subbuffer. */
1427 ret
= ustctl_put_subbuf(stream
->ustream
);
1429 ret
= 1; /* Data is pending */
1433 /* Data is NOT pending so ready to be read. */
1441 * Close every metadata stream wait fd of the metadata hash table. This
1442 * function MUST be used very carefully so not to run into a race between the
1443 * metadata thread handling streams and this function closing their wait fd.
1445 * For UST, this is used when the session daemon hangs up. Its the metadata
1446 * producer so calling this is safe because we are assured that no state change
1447 * can occur in the metadata thread for the streams in the hash table.
1449 void lttng_ustconsumer_close_metadata(struct lttng_ht
*metadata_ht
)
1452 struct lttng_ht_iter iter
;
1453 struct lttng_consumer_stream
*stream
;
1455 assert(metadata_ht
);
1456 assert(metadata_ht
->ht
);
1458 DBG("UST consumer closing all metadata streams");
1461 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
1463 int fd
= stream
->wait_fd
;
1466 * Whatever happens here we have to continue to try to close every
1467 * streams. Let's report at least the error on failure.
1469 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
1471 ERR("Unable to close metadata stream fd %d ret %d", fd
, ret
);
1473 DBG("Metadata wait fd %d closed", fd
);
1478 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
1482 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
1484 ERR("Unable to close wakeup fd");
1488 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
1489 struct lttng_consumer_channel
*channel
)
1491 struct lttcomm_metadata_request_msg request
;
1492 struct lttcomm_consumer_msg msg
;
1493 enum lttng_error_code ret_code
= LTTNG_OK
;
1494 uint64_t len
, key
, offset
;
1498 assert(channel
->metadata_cache
);
1500 /* send the metadata request to sessiond */
1501 switch (consumer_data
.type
) {
1502 case LTTNG_CONSUMER64_UST
:
1503 request
.bits_per_long
= 64;
1505 case LTTNG_CONSUMER32_UST
:
1506 request
.bits_per_long
= 32;
1509 request
.bits_per_long
= 0;
1513 request
.session_id
= channel
->session_id
;
1514 request
.uid
= channel
->uid
;
1515 request
.key
= channel
->key
;
1516 DBG("Sending metadata request to sessiond, session %" PRIu64
,
1517 channel
->session_id
);
1519 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
1522 ERR("Asking metadata to sessiond");
1526 /* Receive the metadata from sessiond */
1527 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
1529 if (ret
!= sizeof(msg
)) {
1530 DBG("Consumer received unexpected message size %d (expects %zu)",
1532 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1534 * The ret value might 0 meaning an orderly shutdown but this is ok
1535 * since the caller handles this.
1540 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
1541 /* No registry found */
1542 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
1546 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
1547 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
1552 len
= msg
.u
.push_metadata
.len
;
1553 key
= msg
.u
.push_metadata
.key
;
1554 offset
= msg
.u
.push_metadata
.target_offset
;
1556 assert(key
== channel
->key
);
1558 DBG("No new metadata to receive for key %" PRIu64
, key
);
1561 /* Tell session daemon we are ready to receive the metadata. */
1562 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
1564 if (ret
< 0 || len
== 0) {
1566 * Somehow, the session daemon is not responding anymore or there is
1567 * nothing to receive.
1572 ret_code
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
1573 key
, offset
, len
, channel
);
1574 if (ret_code
>= 0) {
1576 * Only send the status msg if the sessiond is alive meaning a positive
1579 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret_code
);