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
)
122 return consumer_allocate_channel(key
, session_id
, pathname
, name
, uid
, gid
,
123 relayd_id
, output
, tracefile_size
, tracefile_count
);
127 * Allocate and return a consumer stream object. If _alloc_ret is not NULL, the
128 * error value if applicable is set in it else it is kept untouched.
130 * Return NULL on error else the newly allocated stream object.
132 static struct lttng_consumer_stream
*allocate_stream(int cpu
, int key
,
133 struct lttng_consumer_channel
*channel
,
134 struct lttng_consumer_local_data
*ctx
, int *_alloc_ret
)
137 struct lttng_consumer_stream
*stream
= NULL
;
142 stream
= consumer_allocate_stream(channel
->key
,
144 LTTNG_CONSUMER_ACTIVE_STREAM
,
153 if (stream
== NULL
) {
157 * We could not find the channel. Can happen if cpu hotplug
158 * happens while tearing down.
160 DBG3("Could not find channel");
165 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
171 stream
->chan
= channel
;
175 *_alloc_ret
= alloc_ret
;
181 * Send the given stream pointer to the corresponding thread.
183 * Returns 0 on success else a negative value.
185 static int send_stream_to_thread(struct lttng_consumer_stream
*stream
,
186 struct lttng_consumer_local_data
*ctx
)
189 struct lttng_pipe
*stream_pipe
;
191 /* Get the right pipe where the stream will be sent. */
192 if (stream
->metadata_flag
) {
193 stream_pipe
= ctx
->consumer_metadata_pipe
;
195 stream_pipe
= ctx
->consumer_data_pipe
;
198 ret
= lttng_pipe_write(stream_pipe
, &stream
, sizeof(stream
));
200 ERR("Consumer write %s stream to pipe %d",
201 stream
->metadata_flag
? "metadata" : "data",
202 lttng_pipe_get_writefd(stream_pipe
));
209 * Search for a relayd object related to the stream. If found, send the stream
212 * On success, returns 0 else a negative value.
214 static int send_stream_to_relayd(struct lttng_consumer_stream
*stream
)
217 struct consumer_relayd_sock_pair
*relayd
;
221 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
222 if (relayd
!= NULL
) {
223 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
224 /* Add stream on the relayd */
225 ret
= relayd_add_stream(&relayd
->control_sock
, stream
->name
,
226 stream
->chan
->pathname
, &stream
->relayd_stream_id
,
227 stream
->chan
->tracefile_size
,
228 stream
->chan
->tracefile_count
);
229 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
233 } else if (stream
->net_seq_idx
!= (uint64_t) -1ULL) {
234 ERR("Network sequence index %" PRIu64
" unknown. Not adding stream.",
235 stream
->net_seq_idx
);
245 * Create streams for the given channel using liblttng-ust-ctl.
247 * Return 0 on success else a negative value.
249 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
250 struct lttng_consumer_local_data
*ctx
)
253 struct ustctl_consumer_stream
*ustream
;
254 struct lttng_consumer_stream
*stream
;
260 * While a stream is available from ustctl. When NULL is returned, we've
261 * reached the end of the possible stream for the channel.
263 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
266 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
268 /* Allocate consumer stream object. */
269 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
273 stream
->ustream
= ustream
;
275 * Store it so we can save multiple function calls afterwards since
276 * this value is used heavily in the stream threads. This is UST
277 * specific so this is why it's done after allocation.
279 stream
->wait_fd
= wait_fd
;
282 * Increment channel refcount since the channel reference has now been
283 * assigned in the allocation process above.
285 uatomic_inc(&stream
->chan
->refcount
);
288 * Order is important this is why a list is used. On error, the caller
289 * should clean this list.
291 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
293 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
294 &stream
->max_sb_size
);
296 ERR("ustctl_get_max_subbuf_size failed for stream %s",
301 /* Do actions once stream has been received. */
302 if (ctx
->on_recv_stream
) {
303 ret
= ctx
->on_recv_stream(stream
);
309 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
310 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
312 /* Set next CPU stream. */
313 channel
->streams
.count
= ++cpu
;
315 /* Keep stream reference when creating metadata. */
316 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
317 channel
->metadata_stream
= stream
;
329 * Create an UST channel with the given attributes and send it to the session
330 * daemon using the ust ctl API.
332 * Return 0 on success or else a negative value.
334 static int create_ust_channel(struct ustctl_consumer_channel_attr
*attr
,
335 struct ustctl_consumer_channel
**chanp
)
338 struct ustctl_consumer_channel
*channel
;
343 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
344 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
345 "switch_timer_interval: %u, read_timer_interval: %u, "
346 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
347 attr
->num_subbuf
, attr
->switch_timer_interval
,
348 attr
->read_timer_interval
, attr
->output
, attr
->type
);
350 channel
= ustctl_create_channel(attr
);
365 * Send a single given stream to the session daemon using the sock.
367 * Return 0 on success else a negative value.
369 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
376 DBG2("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
378 /* Send stream to session daemon. */
379 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
389 * Send channel to sessiond.
391 * Return 0 on success or else a negative value.
393 static int send_sessiond_channel(int sock
,
394 struct lttng_consumer_channel
*channel
,
395 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
398 struct lttng_consumer_stream
*stream
;
404 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
406 /* Send channel to sessiond. */
407 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
412 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
417 /* The channel was sent successfully to the sessiond at this point. */
418 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
419 /* Try to send the stream to the relayd if one is available. */
420 ret
= send_stream_to_relayd(stream
);
423 * Flag that the relayd was the problem here probably due to a
424 * communicaton error on the socket.
432 /* Send stream to session daemon. */
433 ret
= send_sessiond_stream(sock
, stream
);
439 /* Tell sessiond there is no more stream. */
440 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
445 DBG("UST consumer NULL stream sent to sessiond");
454 * Creates a channel and streams and add the channel it to the channel internal
455 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
458 * Return 0 on success or else, a negative value is returned and the channel
459 * MUST be destroyed by consumer_del_channel().
461 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
462 struct lttng_consumer_channel
*channel
,
463 struct ustctl_consumer_channel_attr
*attr
)
472 * This value is still used by the kernel consumer since for the kernel,
473 * the stream ownership is not IN the consumer so we need to have the
474 * number of left stream that needs to be initialized so we can know when
475 * to delete the channel (see consumer.c).
477 * As for the user space tracer now, the consumer creates and sends the
478 * stream to the session daemon which only sends them to the application
479 * once every stream of a channel is received making this value useless
480 * because we they will be added to the poll thread before the application
481 * receives them. This ensures that a stream can not hang up during
482 * initilization of a channel.
484 channel
->nb_init_stream_left
= 0;
486 /* The reply msg status is handled in the following call. */
487 ret
= create_ust_channel(attr
, &channel
->uchan
);
492 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
494 /* Open all streams for this channel. */
495 ret
= create_ust_streams(channel
, ctx
);
505 * Send all stream of a channel to the right thread handling it.
507 * On error, return a negative value else 0 on success.
509 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
510 struct lttng_consumer_local_data
*ctx
)
513 struct lttng_consumer_stream
*stream
, *stmp
;
518 /* Send streams to the corresponding thread. */
519 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
521 /* Sending the stream to the thread. */
522 ret
= send_stream_to_thread(stream
, ctx
);
525 * If we are unable to send the stream to the thread, there is
526 * a big problem so just stop everything.
531 /* Remove node from the channel stream list. */
532 cds_list_del(&stream
->send_node
);
540 * Write metadata to the given channel using ustctl to convert the string to
542 * Called only from consumer_metadata_cache_write.
543 * The metadata cache lock MUST be acquired to write in the cache.
545 * Return 0 on success else a negative value.
547 int lttng_ustconsumer_push_metadata(struct lttng_consumer_channel
*metadata
,
548 const char *metadata_str
, uint64_t target_offset
, uint64_t len
)
553 assert(metadata_str
);
555 DBG("UST consumer writing metadata to channel %s", metadata
->name
);
557 if (!metadata
->metadata_stream
) {
562 assert(target_offset
<= metadata
->metadata_cache
->max_offset
);
563 ret
= ustctl_write_metadata_to_channel(metadata
->uchan
,
564 metadata_str
+ target_offset
, len
);
566 ERR("ustctl write metadata fail with ret %d, len %" PRIu64
, ret
, len
);
570 ustctl_flush_buffer(metadata
->metadata_stream
->ustream
, 1);
577 * Flush channel's streams using the given key to retrieve the channel.
579 * Return 0 on success else an LTTng error code.
581 static int flush_channel(uint64_t chan_key
)
584 struct lttng_consumer_channel
*channel
;
585 struct lttng_consumer_stream
*stream
;
587 struct lttng_ht_iter iter
;
589 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
592 channel
= consumer_find_channel(chan_key
);
594 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
595 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
599 ht
= consumer_data
.stream_per_chan_id_ht
;
601 /* For each stream of the channel id, flush it. */
602 cds_lfht_for_each_entry_duplicate(ht
->ht
,
603 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
604 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
605 ustctl_flush_buffer(stream
->ustream
, 1);
613 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
614 * RCU read side lock MUST be acquired before calling this function.
616 * Return 0 on success else an LTTng error code.
618 static int close_metadata(uint64_t chan_key
)
621 struct lttng_consumer_channel
*channel
;
623 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
625 channel
= consumer_find_channel(chan_key
);
627 ERR("UST consumer close metadata %" PRIu64
" not found", chan_key
);
628 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
632 pthread_mutex_lock(&consumer_data
.lock
);
634 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
638 if (channel
->switch_timer_enabled
== 1) {
639 DBG("Deleting timer on metadata channel");
640 consumer_timer_switch_stop(channel
);
643 if (channel
->metadata_stream
) {
644 ret
= ustctl_stream_close_wakeup_fd(channel
->metadata_stream
->ustream
);
646 ERR("UST consumer unable to close fd of metadata (ret: %d)", ret
);
647 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
653 pthread_mutex_unlock(&consumer_data
.lock
);
659 * RCU read side lock MUST be acquired before calling this function.
661 * Return 0 on success else an LTTng error code.
663 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
666 struct lttng_consumer_channel
*metadata
;
668 DBG("UST consumer setup metadata key %" PRIu64
, key
);
670 metadata
= consumer_find_channel(key
);
672 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
673 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
678 * Send metadata stream to relayd if one available. Availability is
679 * known if the stream is still in the list of the channel.
681 if (cds_list_empty(&metadata
->streams
.head
)) {
682 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
683 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
687 /* Send metadata stream to relayd if needed. */
688 ret
= send_stream_to_relayd(metadata
->metadata_stream
);
690 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
694 ret
= send_streams_to_thread(metadata
, ctx
);
697 * If we are unable to send the stream to the thread, there is
698 * a big problem so just stop everything.
700 ret
= LTTCOMM_CONSUMERD_FATAL
;
703 /* List MUST be empty after or else it could be reused. */
704 assert(cds_list_empty(&metadata
->streams
.head
));
713 * Receive the metadata updates from the sessiond.
715 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
716 uint64_t len
, struct lttng_consumer_channel
*channel
)
718 int ret
, ret_code
= LTTNG_OK
;
721 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
723 metadata_str
= zmalloc(len
* sizeof(char));
725 PERROR("zmalloc metadata string");
726 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
730 /* Receive metadata string. */
731 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
733 /* Session daemon is dead so return gracefully. */
739 * XXX: The consumer data lock is acquired before calling metadata cache
740 * write which calls push metadata that MUST be protected by the consumer
741 * lock in order to be able to check the validity of the metadata stream of
744 * Note that this will be subject to change to better fine grained locking
745 * and ultimately try to get rid of this global consumer data lock.
747 pthread_mutex_lock(&consumer_data
.lock
);
749 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
750 ret
= consumer_metadata_cache_write(channel
, offset
, len
, metadata_str
);
752 /* Unable to handle metadata. Notify session daemon. */
753 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
755 * Skip metadata flush on write error since the offset and len might
756 * not have been updated which could create an infinite loop below when
757 * waiting for the metadata cache to be flushed.
759 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
760 pthread_mutex_unlock(&consumer_data
.lock
);
763 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
764 pthread_mutex_unlock(&consumer_data
.lock
);
766 while (consumer_metadata_cache_flushed(channel
, offset
+ len
)) {
767 DBG("Waiting for metadata to be flushed");
768 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
778 * Receive command from session daemon and process it.
780 * Return 1 on success else a negative value or 0.
782 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
783 int sock
, struct pollfd
*consumer_sockpoll
)
786 enum lttng_error_code ret_code
= LTTNG_OK
;
787 struct lttcomm_consumer_msg msg
;
788 struct lttng_consumer_channel
*channel
= NULL
;
790 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
791 if (ret
!= sizeof(msg
)) {
792 DBG("Consumer received unexpected message size %zd (expects %zu)",
794 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
796 * The ret value might 0 meaning an orderly shutdown but this is ok
797 * since the caller handles this.
804 if (msg
.cmd_type
== LTTNG_CONSUMER_STOP
) {
806 * Notify the session daemon that the command is completed.
808 * On transport layer error, the function call will print an error
809 * message so handling the returned code is a bit useless since we
810 * return an error code anyway.
812 (void) consumer_send_status_msg(sock
, ret_code
);
816 /* relayd needs RCU read-side lock */
819 switch (msg
.cmd_type
) {
820 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
822 /* Session daemon status message are handled in the following call. */
823 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
824 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
825 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
);
828 case LTTNG_CONSUMER_DESTROY_RELAYD
:
830 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
831 struct consumer_relayd_sock_pair
*relayd
;
833 DBG("UST consumer destroying relayd %" PRIu64
, index
);
835 /* Get relayd reference if exists. */
836 relayd
= consumer_find_relayd(index
);
837 if (relayd
== NULL
) {
838 DBG("Unable to find relayd %" PRIu64
, index
);
839 ret_code
= LTTNG_ERR_NO_CONSUMER
;
843 * Each relayd socket pair has a refcount of stream attached to it
844 * which tells if the relayd is still active or not depending on the
847 * This will set the destroy flag of the relayd object and destroy it
848 * if the refcount reaches zero when called.
850 * The destroy can happen either here or when a stream fd hangs up.
853 consumer_flag_relayd_for_destroy(relayd
);
856 goto end_msg_sessiond
;
858 case LTTNG_CONSUMER_UPDATE_STREAM
:
863 case LTTNG_CONSUMER_DATA_PENDING
:
865 int ret
, is_data_pending
;
866 uint64_t id
= msg
.u
.data_pending
.session_id
;
868 DBG("UST consumer data pending command for id %" PRIu64
, id
);
870 is_data_pending
= consumer_data_pending(id
);
872 /* Send back returned value to session daemon */
873 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
874 sizeof(is_data_pending
));
876 DBG("Error when sending the data pending ret code: %d", ret
);
881 * No need to send back a status message since the data pending
882 * returned value is the response.
886 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
889 struct ustctl_consumer_channel_attr attr
;
891 /* Create a plain object and reserve a channel key. */
892 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
893 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
894 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
895 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
896 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
897 msg
.u
.ask_channel
.tracefile_size
,
898 msg
.u
.ask_channel
.tracefile_count
);
900 goto end_channel_error
;
903 /* Build channel attributes from received message. */
904 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
905 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
906 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
907 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
908 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
909 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
910 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
912 /* Translate the event output type to UST. */
913 switch (channel
->output
) {
914 case LTTNG_EVENT_SPLICE
:
915 /* Splice not supported so fallback on mmap(). */
916 case LTTNG_EVENT_MMAP
:
918 attr
.output
= CONSUMER_CHANNEL_MMAP
;
922 /* Translate and save channel type. */
923 switch (msg
.u
.ask_channel
.type
) {
924 case LTTNG_UST_CHAN_PER_CPU
:
925 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
926 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
928 * Set refcount to 1 for owner. Below, we will
929 * pass ownership to the
930 * consumer_thread_channel_poll() thread.
932 channel
->refcount
= 1;
934 case LTTNG_UST_CHAN_METADATA
:
935 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
936 attr
.type
= LTTNG_UST_CHAN_METADATA
;
943 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
945 goto end_channel_error
;
948 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
949 ret
= consumer_metadata_cache_allocate(channel
);
951 ERR("Allocating metadata cache");
952 goto end_channel_error
;
954 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
955 attr
.switch_timer_interval
= 0;
959 * Add the channel to the internal state AFTER all streams were created
960 * and successfully sent to session daemon. This way, all streams must
961 * be ready before this channel is visible to the threads.
962 * If add_channel succeeds, ownership of the channel is
963 * passed to consumer_thread_channel_poll().
965 ret
= add_channel(channel
, ctx
);
967 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
968 if (channel
->switch_timer_enabled
== 1) {
969 consumer_timer_switch_stop(channel
);
971 consumer_metadata_cache_destroy(channel
);
973 goto end_channel_error
;
977 * Channel and streams are now created. Inform the session daemon that
978 * everything went well and should wait to receive the channel and
979 * streams with ustctl API.
981 ret
= consumer_send_status_channel(sock
, channel
);
984 * There is probably a problem on the socket.
991 case LTTNG_CONSUMER_GET_CHANNEL
:
993 int ret
, relayd_err
= 0;
994 uint64_t key
= msg
.u
.get_channel
.key
;
995 struct lttng_consumer_channel
*channel
;
997 channel
= consumer_find_channel(key
);
999 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1000 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
1001 goto end_msg_sessiond
;
1004 /* Inform sessiond that we are about to send channel and streams. */
1005 ret
= consumer_send_status_msg(sock
, LTTNG_OK
);
1007 /* Somehow, the session daemon is not responding anymore. */
1011 /* Send everything to sessiond. */
1012 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1016 * We were unable to send to the relayd the stream so avoid
1017 * sending back a fatal error to the thread since this is OK
1018 * and the consumer can continue its work.
1020 ret_code
= LTTNG_ERR_RELAYD_CONNECT_FAIL
;
1021 goto end_msg_sessiond
;
1024 * The communicaton was broken hence there is a bad state between
1025 * the consumer and sessiond so stop everything.
1030 ret
= send_streams_to_thread(channel
, ctx
);
1033 * If we are unable to send the stream to the thread, there is
1034 * a big problem so just stop everything.
1038 /* List MUST be empty after or else it could be reused. */
1039 assert(cds_list_empty(&channel
->streams
.head
));
1041 goto end_msg_sessiond
;
1043 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1045 uint64_t key
= msg
.u
.destroy_channel
.key
;
1048 * Only called if streams have not been sent to stream
1049 * manager thread. However, channel has been sent to
1050 * channel manager thread.
1052 notify_thread_del_channel(ctx
, key
);
1053 goto end_msg_sessiond
;
1055 case LTTNG_CONSUMER_CLOSE_METADATA
:
1059 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1064 goto end_msg_sessiond
;
1066 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1070 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1075 goto end_msg_sessiond
;
1077 case LTTNG_CONSUMER_PUSH_METADATA
:
1080 uint64_t len
= msg
.u
.push_metadata
.len
;
1081 uint64_t key
= msg
.u
.push_metadata
.key
;
1082 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1083 struct lttng_consumer_channel
*channel
;
1085 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1088 channel
= consumer_find_channel(key
);
1090 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
1091 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
1092 goto end_msg_sessiond
;
1095 /* Tell session daemon we are ready to receive the metadata. */
1096 ret
= consumer_send_status_msg(sock
, LTTNG_OK
);
1098 /* Somehow, the session daemon is not responding anymore. */
1102 /* Wait for more data. */
1103 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
1107 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1110 /* error receiving from sessiond */
1114 goto end_msg_sessiond
;
1117 case LTTNG_CONSUMER_SETUP_METADATA
:
1121 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1125 goto end_msg_sessiond
;
1135 * Return 1 to indicate success since the 0 value can be a socket
1136 * shutdown during the recv() or send() call.
1142 * The returned value here is not useful since either way we'll return 1 to
1143 * the caller because the session daemon socket management is done
1144 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1146 ret
= consumer_send_status_msg(sock
, ret_code
);
1155 * Free channel here since no one has a reference to it. We don't
1156 * free after that because a stream can store this pointer.
1158 destroy_channel(channel
);
1160 /* We have to send a status channel message indicating an error. */
1161 ret
= consumer_send_status_channel(sock
, NULL
);
1163 /* Stop everything if session daemon can not be notified. */
1170 /* This will issue a consumer stop. */
1175 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1176 * compiled out, we isolate it in this library.
1178 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1182 assert(stream
->ustream
);
1184 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1188 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1189 * compiled out, we isolate it in this library.
1191 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1194 assert(stream
->ustream
);
1196 return ustctl_get_mmap_base(stream
->ustream
);
1200 * Take a snapshot for a specific fd
1202 * Returns 0 on success, < 0 on error
1204 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1207 assert(stream
->ustream
);
1209 return ustctl_snapshot(stream
->ustream
);
1213 * Get the produced position
1215 * Returns 0 on success, < 0 on error
1217 int lttng_ustconsumer_get_produced_snapshot(
1218 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1221 assert(stream
->ustream
);
1224 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1228 * Called when the stream signal the consumer that it has hang up.
1230 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1233 assert(stream
->ustream
);
1235 ustctl_flush_buffer(stream
->ustream
, 0);
1236 stream
->hangup_flush_done
= 1;
1239 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1242 assert(chan
->uchan
);
1244 if (chan
->switch_timer_enabled
== 1) {
1245 consumer_timer_switch_stop(chan
);
1247 consumer_metadata_cache_destroy(chan
);
1248 ustctl_destroy_channel(chan
->uchan
);
1251 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
1254 assert(stream
->ustream
);
1256 if (stream
->chan
->switch_timer_enabled
== 1) {
1257 consumer_timer_switch_stop(stream
->chan
);
1259 ustctl_destroy_stream(stream
->ustream
);
1262 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
1263 struct lttng_consumer_local_data
*ctx
)
1265 unsigned long len
, subbuf_size
, padding
;
1269 struct ustctl_consumer_stream
*ustream
;
1272 assert(stream
->ustream
);
1275 DBG2("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
1278 /* Ease our life for what's next. */
1279 ustream
= stream
->ustream
;
1281 /* We can consume the 1 byte written into the wait_fd by UST */
1282 if (!stream
->hangup_flush_done
) {
1286 readlen
= read(stream
->wait_fd
, &dummy
, 1);
1287 } while (readlen
== -1 && errno
== EINTR
);
1288 if (readlen
== -1) {
1294 /* Get the next subbuffer */
1295 err
= ustctl_get_next_subbuf(ustream
);
1297 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
1299 * This is a debug message even for single-threaded consumer,
1300 * because poll() have more relaxed criterions than get subbuf,
1301 * so get_subbuf may fail for short race windows where poll()
1302 * would issue wakeups.
1304 DBG("Reserving sub buffer failed (everything is normal, "
1305 "it is due to concurrency) [ret: %d]", err
);
1308 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
1309 /* Get the full padded subbuffer size */
1310 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
1313 /* Get subbuffer data size (without padding) */
1314 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
1317 /* Make sure we don't get a subbuffer size bigger than the padded */
1318 assert(len
>= subbuf_size
);
1320 padding
= len
- subbuf_size
;
1321 /* write the subbuffer to the tracefile */
1322 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
);
1324 * The mmap operation should write subbuf_size amount of data when network
1325 * streaming or the full padding (len) size when we are _not_ streaming.
1327 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
1328 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
1330 * Display the error but continue processing to try to release the
1331 * subbuffer. This is a DBG statement since any unexpected kill or
1332 * signal, the application gets unregistered, relayd gets closed or
1333 * anything that affects the buffer lifetime will trigger this error.
1334 * So, for the sake of the user, don't print this error since it can
1335 * happen and it is OK with the code flow.
1337 DBG("Error writing to tracefile "
1338 "(ret: %ld != len: %lu != subbuf_size: %lu)",
1339 ret
, len
, subbuf_size
);
1341 err
= ustctl_put_next_subbuf(ustream
);
1349 * Called when a stream is created.
1351 * Return 0 on success or else a negative value.
1353 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
1357 /* Don't create anything if this is set for streaming. */
1358 if (stream
->net_seq_idx
== (uint64_t) -1ULL) {
1359 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
1360 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
1361 stream
->uid
, stream
->gid
);
1365 stream
->out_fd
= ret
;
1366 stream
->tracefile_size_current
= 0;
1375 * Check if data is still being extracted from the buffers for a specific
1376 * stream. Consumer data lock MUST be acquired before calling this function
1377 * and the stream lock.
1379 * Return 1 if the traced data are still getting read else 0 meaning that the
1380 * data is available for trace viewer reading.
1382 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
1387 assert(stream
->ustream
);
1389 DBG("UST consumer checking data pending");
1391 ret
= ustctl_get_next_subbuf(stream
->ustream
);
1393 /* There is still data so let's put back this subbuffer. */
1394 ret
= ustctl_put_subbuf(stream
->ustream
);
1396 ret
= 1; /* Data is pending */
1400 /* Data is NOT pending so ready to be read. */
1408 * Close every metadata stream wait fd of the metadata hash table. This
1409 * function MUST be used very carefully so not to run into a race between the
1410 * metadata thread handling streams and this function closing their wait fd.
1412 * For UST, this is used when the session daemon hangs up. Its the metadata
1413 * producer so calling this is safe because we are assured that no state change
1414 * can occur in the metadata thread for the streams in the hash table.
1416 void lttng_ustconsumer_close_metadata(struct lttng_ht
*metadata_ht
)
1419 struct lttng_ht_iter iter
;
1420 struct lttng_consumer_stream
*stream
;
1422 assert(metadata_ht
);
1423 assert(metadata_ht
->ht
);
1425 DBG("UST consumer closing all metadata streams");
1428 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
1430 int fd
= stream
->wait_fd
;
1433 * Whatever happens here we have to continue to try to close every
1434 * streams. Let's report at least the error on failure.
1436 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
1438 ERR("Unable to close metadata stream fd %d ret %d", fd
, ret
);
1440 DBG("Metadata wait fd %d closed", fd
);
1445 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
1449 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
1451 ERR("Unable to close wakeup fd");
1455 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
1456 struct lttng_consumer_channel
*channel
)
1458 struct lttcomm_metadata_request_msg request
;
1459 struct lttcomm_consumer_msg msg
;
1460 enum lttng_error_code ret_code
= LTTNG_OK
;
1461 uint64_t len
, key
, offset
;
1465 assert(channel
->metadata_cache
);
1467 /* send the metadata request to sessiond */
1468 switch (consumer_data
.type
) {
1469 case LTTNG_CONSUMER64_UST
:
1470 request
.bits_per_long
= 64;
1472 case LTTNG_CONSUMER32_UST
:
1473 request
.bits_per_long
= 32;
1476 request
.bits_per_long
= 0;
1480 request
.session_id
= channel
->session_id
;
1481 request
.uid
= channel
->uid
;
1482 request
.key
= channel
->key
;
1483 DBG("Sending metadata request to sessiond, session %" PRIu64
,
1484 channel
->session_id
);
1486 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
1489 ERR("Asking metadata to sessiond");
1493 /* Receive the metadata from sessiond */
1494 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
1496 if (ret
!= sizeof(msg
)) {
1497 DBG("Consumer received unexpected message size %d (expects %zu)",
1499 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1501 * The ret value might 0 meaning an orderly shutdown but this is ok
1502 * since the caller handles this.
1507 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
1508 /* No registry found */
1509 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
1513 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
1514 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
1519 len
= msg
.u
.push_metadata
.len
;
1520 key
= msg
.u
.push_metadata
.key
;
1521 offset
= msg
.u
.push_metadata
.target_offset
;
1523 assert(key
== channel
->key
);
1525 DBG("No new metadata to receive for key %" PRIu64
, key
);
1528 /* Tell session daemon we are ready to receive the metadata. */
1529 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
1531 if (ret
< 0 || len
== 0) {
1533 * Somehow, the session daemon is not responding anymore or there is
1534 * nothing to receive.
1539 ret_code
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
1540 key
, offset
, len
, channel
);
1541 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret_code
);