2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@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,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
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.
22 #include <lttng/ust-ctl.h>
28 #include <sys/socket.h>
30 #include <sys/types.h>
33 #include <urcu/list.h>
36 #include <bin/lttng-consumerd/health-consumerd.h>
37 #include <common/common.h>
38 #include <common/sessiond-comm/sessiond-comm.h>
39 #include <common/relayd/relayd.h>
40 #include <common/compat/fcntl.h>
41 #include <common/compat/endian.h>
42 #include <common/consumer/consumer-metadata-cache.h>
43 #include <common/consumer/consumer-stream.h>
44 #include <common/consumer/consumer-timer.h>
45 #include <common/utils.h>
46 #include <common/index/index.h>
48 #include "ust-consumer.h"
50 #define INT_MAX_STR_LEN 12 /* includes \0 */
52 extern struct lttng_consumer_global_data consumer_data
;
53 extern int consumer_poll_timeout
;
56 * Free channel object and all streams associated with it. This MUST be used
57 * only and only if the channel has _NEVER_ been added to the global channel
60 static void destroy_channel(struct lttng_consumer_channel
*channel
)
62 struct lttng_consumer_stream
*stream
, *stmp
;
66 DBG("UST consumer cleaning stream list");
68 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
73 cds_list_del(&stream
->send_node
);
74 ustctl_destroy_stream(stream
->ustream
);
79 * If a channel is available meaning that was created before the streams
83 lttng_ustconsumer_del_channel(channel
);
84 lttng_ustconsumer_free_channel(channel
);
90 * Add channel to internal consumer state.
92 * Returns 0 on success or else a negative value.
94 static int add_channel(struct lttng_consumer_channel
*channel
,
95 struct lttng_consumer_local_data
*ctx
)
102 if (ctx
->on_recv_channel
!= NULL
) {
103 ret
= ctx
->on_recv_channel(channel
);
105 ret
= consumer_add_channel(channel
, ctx
);
106 } else if (ret
< 0) {
107 /* Most likely an ENOMEM. */
108 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
112 ret
= consumer_add_channel(channel
, ctx
);
115 DBG("UST consumer channel added (key: %" PRIu64
")", channel
->key
);
122 * Allocate and return a consumer channel object.
124 static struct lttng_consumer_channel
*allocate_channel(uint64_t session_id
,
125 const char *pathname
, const char *name
, uid_t uid
, gid_t gid
,
126 uint64_t relayd_id
, uint64_t key
, enum lttng_event_output output
,
127 uint64_t tracefile_size
, uint64_t tracefile_count
,
128 uint64_t session_id_per_pid
, unsigned int monitor
,
129 unsigned int live_timer_interval
,
130 const char *root_shm_path
, const char *shm_path
)
135 return consumer_allocate_channel(key
, session_id
, pathname
, name
, uid
,
136 gid
, relayd_id
, output
, tracefile_size
,
137 tracefile_count
, session_id_per_pid
, monitor
,
138 live_timer_interval
, root_shm_path
, shm_path
);
142 * Allocate and return a consumer stream object. If _alloc_ret is not NULL, the
143 * error value if applicable is set in it else it is kept untouched.
145 * Return NULL on error else the newly allocated stream object.
147 static struct lttng_consumer_stream
*allocate_stream(int cpu
, int key
,
148 struct lttng_consumer_channel
*channel
,
149 struct lttng_consumer_local_data
*ctx
, int *_alloc_ret
)
152 struct lttng_consumer_stream
*stream
= NULL
;
157 stream
= consumer_allocate_stream(channel
->key
,
159 LTTNG_CONSUMER_ACTIVE_STREAM
,
169 if (stream
== NULL
) {
173 * We could not find the channel. Can happen if cpu hotplug
174 * happens while tearing down.
176 DBG3("Could not find channel");
181 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
187 stream
->chan
= channel
;
191 *_alloc_ret
= alloc_ret
;
197 * Send the given stream pointer to the corresponding thread.
199 * Returns 0 on success else a negative value.
201 static int send_stream_to_thread(struct lttng_consumer_stream
*stream
,
202 struct lttng_consumer_local_data
*ctx
)
205 struct lttng_pipe
*stream_pipe
;
207 /* Get the right pipe where the stream will be sent. */
208 if (stream
->metadata_flag
) {
209 ret
= consumer_add_metadata_stream(stream
);
211 ERR("Consumer add metadata stream %" PRIu64
" failed.",
215 stream_pipe
= ctx
->consumer_metadata_pipe
;
217 ret
= consumer_add_data_stream(stream
);
219 ERR("Consumer add stream %" PRIu64
" failed.",
223 stream_pipe
= ctx
->consumer_data_pipe
;
227 * From this point on, the stream's ownership has been moved away from
228 * the channel and becomes globally visible.
230 stream
->globally_visible
= 1;
232 ret
= lttng_pipe_write(stream_pipe
, &stream
, sizeof(stream
));
234 ERR("Consumer write %s stream to pipe %d",
235 stream
->metadata_flag
? "metadata" : "data",
236 lttng_pipe_get_writefd(stream_pipe
));
237 if (stream
->metadata_flag
) {
238 consumer_del_stream_for_metadata(stream
);
240 consumer_del_stream_for_data(stream
);
248 int get_stream_shm_path(char *stream_shm_path
, const char *shm_path
, int cpu
)
250 char cpu_nr
[INT_MAX_STR_LEN
]; /* int max len */
253 strncpy(stream_shm_path
, shm_path
, PATH_MAX
);
254 stream_shm_path
[PATH_MAX
- 1] = '\0';
255 ret
= snprintf(cpu_nr
, INT_MAX_STR_LEN
, "%i", cpu
);
260 strncat(stream_shm_path
, cpu_nr
,
261 PATH_MAX
- strlen(stream_shm_path
) - 1);
268 * Create streams for the given channel using liblttng-ust-ctl.
270 * Return 0 on success else a negative value.
272 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
273 struct lttng_consumer_local_data
*ctx
)
276 struct ustctl_consumer_stream
*ustream
;
277 struct lttng_consumer_stream
*stream
;
283 * While a stream is available from ustctl. When NULL is returned, we've
284 * reached the end of the possible stream for the channel.
286 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
288 int ust_metadata_pipe
[2];
290 health_code_update();
292 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& channel
->monitor
) {
293 ret
= utils_create_pipe_cloexec_nonblock(ust_metadata_pipe
);
295 ERR("Create ust metadata poll pipe");
298 wait_fd
= ust_metadata_pipe
[0];
300 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
303 /* Allocate consumer stream object. */
304 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
308 stream
->ustream
= ustream
;
310 * Store it so we can save multiple function calls afterwards since
311 * this value is used heavily in the stream threads. This is UST
312 * specific so this is why it's done after allocation.
314 stream
->wait_fd
= wait_fd
;
317 * Increment channel refcount since the channel reference has now been
318 * assigned in the allocation process above.
320 if (stream
->chan
->monitor
) {
321 uatomic_inc(&stream
->chan
->refcount
);
325 * Order is important this is why a list is used. On error, the caller
326 * should clean this list.
328 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
330 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
331 &stream
->max_sb_size
);
333 ERR("ustctl_get_max_subbuf_size failed for stream %s",
338 /* Do actions once stream has been received. */
339 if (ctx
->on_recv_stream
) {
340 ret
= ctx
->on_recv_stream(stream
);
346 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
347 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
349 /* Set next CPU stream. */
350 channel
->streams
.count
= ++cpu
;
352 /* Keep stream reference when creating metadata. */
353 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
354 channel
->metadata_stream
= stream
;
355 if (channel
->monitor
) {
356 /* Set metadata poll pipe if we created one */
357 memcpy(stream
->ust_metadata_poll_pipe
,
359 sizeof(ust_metadata_pipe
));
372 * create_posix_shm is never called concurrently within a process.
375 int create_posix_shm(void)
377 char tmp_name
[NAME_MAX
];
380 ret
= snprintf(tmp_name
, NAME_MAX
, "/ust-shm-consumer-%d", getpid());
386 * Allocate shm, and immediately unlink its shm oject, keeping
387 * only the file descriptor as a reference to the object.
388 * We specifically do _not_ use the / at the beginning of the
389 * pathname so that some OS implementations can keep it local to
390 * the process (POSIX leaves this implementation-defined).
392 shmfd
= shm_open(tmp_name
, O_CREAT
| O_EXCL
| O_RDWR
, 0700);
397 ret
= shm_unlink(tmp_name
);
398 if (ret
< 0 && errno
!= ENOENT
) {
399 PERROR("shm_unlink");
400 goto error_shm_release
;
413 static int open_ust_stream_fd(struct lttng_consumer_channel
*channel
,
414 struct ustctl_consumer_channel_attr
*attr
,
417 char shm_path
[PATH_MAX
];
420 if (!channel
->shm_path
[0]) {
421 return create_posix_shm();
423 ret
= get_stream_shm_path(shm_path
, channel
->shm_path
, cpu
);
427 return run_as_open(shm_path
,
428 O_RDWR
| O_CREAT
| O_EXCL
, S_IRUSR
| S_IWUSR
,
429 channel
->uid
, channel
->gid
);
436 * Create an UST channel with the given attributes and send it to the session
437 * daemon using the ust ctl API.
439 * Return 0 on success or else a negative value.
441 static int create_ust_channel(struct lttng_consumer_channel
*channel
,
442 struct ustctl_consumer_channel_attr
*attr
,
443 struct ustctl_consumer_channel
**ust_chanp
)
445 int ret
, nr_stream_fds
, i
, j
;
447 struct ustctl_consumer_channel
*ust_channel
;
453 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
454 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
455 "switch_timer_interval: %u, read_timer_interval: %u, "
456 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
457 attr
->num_subbuf
, attr
->switch_timer_interval
,
458 attr
->read_timer_interval
, attr
->output
, attr
->type
);
460 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
)
463 nr_stream_fds
= ustctl_get_nr_stream_per_channel();
464 stream_fds
= zmalloc(nr_stream_fds
* sizeof(*stream_fds
));
469 for (i
= 0; i
< nr_stream_fds
; i
++) {
470 stream_fds
[i
] = open_ust_stream_fd(channel
, attr
, i
);
471 if (stream_fds
[i
] < 0) {
476 ust_channel
= ustctl_create_channel(attr
, stream_fds
, nr_stream_fds
);
481 channel
->nr_stream_fds
= nr_stream_fds
;
482 channel
->stream_fds
= stream_fds
;
483 *ust_chanp
= ust_channel
;
489 for (j
= i
- 1; j
>= 0; j
--) {
492 closeret
= close(stream_fds
[j
]);
496 if (channel
->shm_path
[0]) {
497 char shm_path
[PATH_MAX
];
499 closeret
= get_stream_shm_path(shm_path
,
500 channel
->shm_path
, j
);
502 ERR("Cannot get stream shm path");
504 closeret
= run_as_unlink(shm_path
,
505 channel
->uid
, channel
->gid
);
507 PERROR("unlink %s", shm_path
);
511 /* Try to rmdir all directories under shm_path root. */
512 if (channel
->root_shm_path
[0]) {
513 (void) run_as_rmdir_recursive(channel
->root_shm_path
,
514 channel
->uid
, channel
->gid
);
522 * Send a single given stream to the session daemon using the sock.
524 * Return 0 on success else a negative value.
526 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
533 DBG("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
535 /* Send stream to session daemon. */
536 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
546 * Send channel to sessiond.
548 * Return 0 on success or else a negative value.
550 static int send_sessiond_channel(int sock
,
551 struct lttng_consumer_channel
*channel
,
552 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
554 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
555 struct lttng_consumer_stream
*stream
;
556 uint64_t net_seq_idx
= -1ULL;
562 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
564 if (channel
->relayd_id
!= (uint64_t) -1ULL) {
565 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
567 health_code_update();
569 /* Try to send the stream to the relayd if one is available. */
570 ret
= consumer_send_relayd_stream(stream
, stream
->chan
->pathname
);
573 * Flag that the relayd was the problem here probably due to a
574 * communicaton error on the socket.
579 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
581 if (net_seq_idx
== -1ULL) {
582 net_seq_idx
= stream
->net_seq_idx
;
587 /* Inform sessiond that we are about to send channel and streams. */
588 ret
= consumer_send_status_msg(sock
, ret_code
);
589 if (ret
< 0 || ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
591 * Either the session daemon is not responding or the relayd died so we
597 /* Send channel to sessiond. */
598 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
603 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
608 /* The channel was sent successfully to the sessiond at this point. */
609 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
611 health_code_update();
613 /* Send stream to session daemon. */
614 ret
= send_sessiond_stream(sock
, stream
);
620 /* Tell sessiond there is no more stream. */
621 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
626 DBG("UST consumer NULL stream sent to sessiond");
631 if (ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
638 * Creates a channel and streams and add the channel it to the channel internal
639 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
642 * Return 0 on success or else, a negative value is returned and the channel
643 * MUST be destroyed by consumer_del_channel().
645 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
646 struct lttng_consumer_channel
*channel
,
647 struct ustctl_consumer_channel_attr
*attr
)
656 * This value is still used by the kernel consumer since for the kernel,
657 * the stream ownership is not IN the consumer so we need to have the
658 * number of left stream that needs to be initialized so we can know when
659 * to delete the channel (see consumer.c).
661 * As for the user space tracer now, the consumer creates and sends the
662 * stream to the session daemon which only sends them to the application
663 * once every stream of a channel is received making this value useless
664 * because we they will be added to the poll thread before the application
665 * receives them. This ensures that a stream can not hang up during
666 * initilization of a channel.
668 channel
->nb_init_stream_left
= 0;
670 /* The reply msg status is handled in the following call. */
671 ret
= create_ust_channel(channel
, attr
, &channel
->uchan
);
676 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
679 * For the snapshots (no monitor), we create the metadata streams
680 * on demand, not during the channel creation.
682 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& !channel
->monitor
) {
687 /* Open all streams for this channel. */
688 ret
= create_ust_streams(channel
, ctx
);
698 * Send all stream of a channel to the right thread handling it.
700 * On error, return a negative value else 0 on success.
702 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
703 struct lttng_consumer_local_data
*ctx
)
706 struct lttng_consumer_stream
*stream
, *stmp
;
711 /* Send streams to the corresponding thread. */
712 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
715 health_code_update();
717 /* Sending the stream to the thread. */
718 ret
= send_stream_to_thread(stream
, ctx
);
721 * If we are unable to send the stream to the thread, there is
722 * a big problem so just stop everything.
724 /* Remove node from the channel stream list. */
725 cds_list_del(&stream
->send_node
);
729 /* Remove node from the channel stream list. */
730 cds_list_del(&stream
->send_node
);
739 * Flush channel's streams using the given key to retrieve the channel.
741 * Return 0 on success else an LTTng error code.
743 static int flush_channel(uint64_t chan_key
)
746 struct lttng_consumer_channel
*channel
;
747 struct lttng_consumer_stream
*stream
;
749 struct lttng_ht_iter iter
;
751 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
754 channel
= consumer_find_channel(chan_key
);
756 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
757 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
761 ht
= consumer_data
.stream_per_chan_id_ht
;
763 /* For each stream of the channel id, flush it. */
764 cds_lfht_for_each_entry_duplicate(ht
->ht
,
765 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
766 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
768 health_code_update();
770 pthread_mutex_lock(&stream
->lock
);
773 * Protect against concurrent teardown of a stream.
775 if (cds_lfht_is_node_deleted(&stream
->node
.node
)) {
779 if (!stream
->quiescent
) {
780 ustctl_flush_buffer(stream
->ustream
, 0);
781 stream
->quiescent
= true;
784 pthread_mutex_unlock(&stream
->lock
);
792 * Clear quiescent state from channel's streams using the given key to
793 * retrieve the channel.
795 * Return 0 on success else an LTTng error code.
797 static int clear_quiescent_channel(uint64_t chan_key
)
800 struct lttng_consumer_channel
*channel
;
801 struct lttng_consumer_stream
*stream
;
803 struct lttng_ht_iter iter
;
805 DBG("UST consumer clear quiescent channel key %" PRIu64
, chan_key
);
808 channel
= consumer_find_channel(chan_key
);
810 ERR("UST consumer clear quiescent channel %" PRIu64
" not found", chan_key
);
811 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
815 ht
= consumer_data
.stream_per_chan_id_ht
;
817 /* For each stream of the channel id, clear quiescent state. */
818 cds_lfht_for_each_entry_duplicate(ht
->ht
,
819 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
820 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
822 health_code_update();
824 pthread_mutex_lock(&stream
->lock
);
825 stream
->quiescent
= false;
826 pthread_mutex_unlock(&stream
->lock
);
834 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
835 * RCU read side lock MUST be acquired before calling this function.
837 * Return 0 on success else an LTTng error code.
839 static int close_metadata(uint64_t chan_key
)
842 struct lttng_consumer_channel
*channel
;
843 unsigned int channel_monitor
;
845 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
847 channel
= consumer_find_channel(chan_key
);
850 * This is possible if the metadata thread has issue a delete because
851 * the endpoint point of the stream hung up. There is no way the
852 * session daemon can know about it thus use a DBG instead of an actual
855 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
856 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
860 pthread_mutex_lock(&consumer_data
.lock
);
861 pthread_mutex_lock(&channel
->lock
);
862 channel_monitor
= channel
->monitor
;
863 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
867 lttng_ustconsumer_close_metadata(channel
);
868 pthread_mutex_unlock(&channel
->lock
);
869 pthread_mutex_unlock(&consumer_data
.lock
);
872 * The ownership of a metadata channel depends on the type of
873 * session to which it belongs. In effect, the monitor flag is checked
874 * to determine if this metadata channel is in "snapshot" mode or not.
876 * In the non-snapshot case, the metadata channel is created along with
877 * a single stream which will remain present until the metadata channel
878 * is destroyed (on the destruction of its session). In this case, the
879 * metadata stream in "monitored" by the metadata poll thread and holds
880 * the ownership of its channel.
882 * Closing the metadata will cause the metadata stream's "metadata poll
883 * pipe" to be closed. Closing this pipe will wake-up the metadata poll
884 * thread which will teardown the metadata stream which, in return,
885 * deletes the metadata channel.
887 * In the snapshot case, the metadata stream is created and destroyed
888 * on every snapshot record. Since the channel doesn't have an owner
889 * other than the session daemon, it is safe to destroy it immediately
890 * on reception of the CLOSE_METADATA command.
892 if (!channel_monitor
) {
894 * The channel and consumer_data locks must be
895 * released before this call since consumer_del_channel
896 * re-acquires the channel and consumer_data locks to teardown
897 * the channel and queue its reclamation by the "call_rcu"
900 consumer_del_channel(channel
);
905 pthread_mutex_unlock(&channel
->lock
);
906 pthread_mutex_unlock(&consumer_data
.lock
);
912 * RCU read side lock MUST be acquired before calling this function.
914 * Return 0 on success else an LTTng error code.
916 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
919 struct lttng_consumer_channel
*metadata
;
921 DBG("UST consumer setup metadata key %" PRIu64
, key
);
923 metadata
= consumer_find_channel(key
);
925 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
926 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
931 * In no monitor mode, the metadata channel has no stream(s) so skip the
932 * ownership transfer to the metadata thread.
934 if (!metadata
->monitor
) {
935 DBG("Metadata channel in no monitor");
941 * Send metadata stream to relayd if one available. Availability is
942 * known if the stream is still in the list of the channel.
944 if (cds_list_empty(&metadata
->streams
.head
)) {
945 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
946 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
947 goto error_no_stream
;
950 /* Send metadata stream to relayd if needed. */
951 if (metadata
->metadata_stream
->net_seq_idx
!= (uint64_t) -1ULL) {
952 ret
= consumer_send_relayd_stream(metadata
->metadata_stream
,
955 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
958 ret
= consumer_send_relayd_streams_sent(
959 metadata
->metadata_stream
->net_seq_idx
);
961 ret
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
966 ret
= send_streams_to_thread(metadata
, ctx
);
969 * If we are unable to send the stream to the thread, there is
970 * a big problem so just stop everything.
972 ret
= LTTCOMM_CONSUMERD_FATAL
;
975 /* List MUST be empty after or else it could be reused. */
976 assert(cds_list_empty(&metadata
->streams
.head
));
983 * Delete metadata channel on error. At this point, the metadata stream can
984 * NOT be monitored by the metadata thread thus having the guarantee that
985 * the stream is still in the local stream list of the channel. This call
986 * will make sure to clean that list.
988 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
989 cds_list_del(&metadata
->metadata_stream
->send_node
);
990 metadata
->metadata_stream
= NULL
;
997 * Snapshot the whole metadata.
999 * Returns 0 on success, < 0 on error
1001 static int snapshot_metadata(uint64_t key
, char *path
, uint64_t relayd_id
,
1002 struct lttng_consumer_local_data
*ctx
)
1005 struct lttng_consumer_channel
*metadata_channel
;
1006 struct lttng_consumer_stream
*metadata_stream
;
1011 DBG("UST consumer snapshot metadata with key %" PRIu64
" at path %s",
1016 metadata_channel
= consumer_find_channel(key
);
1017 if (!metadata_channel
) {
1018 ERR("UST snapshot metadata channel not found for key %" PRIu64
,
1023 assert(!metadata_channel
->monitor
);
1025 health_code_update();
1028 * Ask the sessiond if we have new metadata waiting and update the
1029 * consumer metadata cache.
1031 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
, 0, 1);
1036 health_code_update();
1039 * The metadata stream is NOT created in no monitor mode when the channel
1040 * is created on a sessiond ask channel command.
1042 ret
= create_ust_streams(metadata_channel
, ctx
);
1047 metadata_stream
= metadata_channel
->metadata_stream
;
1048 assert(metadata_stream
);
1050 if (relayd_id
!= (uint64_t) -1ULL) {
1051 metadata_stream
->net_seq_idx
= relayd_id
;
1052 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
1057 ret
= utils_create_stream_file(path
, metadata_stream
->name
,
1058 metadata_stream
->chan
->tracefile_size
,
1059 metadata_stream
->tracefile_count_current
,
1060 metadata_stream
->uid
, metadata_stream
->gid
, NULL
);
1064 metadata_stream
->out_fd
= ret
;
1065 metadata_stream
->tracefile_size_current
= 0;
1069 health_code_update();
1071 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
);
1079 * Clean up the stream completly because the next snapshot will use a new
1082 consumer_stream_destroy(metadata_stream
, NULL
);
1083 cds_list_del(&metadata_stream
->send_node
);
1084 metadata_channel
->metadata_stream
= NULL
;
1092 * Take a snapshot of all the stream of a channel.
1094 * Returns 0 on success, < 0 on error
1096 static int snapshot_channel(uint64_t key
, char *path
, uint64_t relayd_id
,
1097 uint64_t nb_packets_per_stream
, struct lttng_consumer_local_data
*ctx
)
1100 unsigned use_relayd
= 0;
1101 unsigned long consumed_pos
, produced_pos
;
1102 struct lttng_consumer_channel
*channel
;
1103 struct lttng_consumer_stream
*stream
;
1110 if (relayd_id
!= (uint64_t) -1ULL) {
1114 channel
= consumer_find_channel(key
);
1116 ERR("UST snapshot channel not found for key %" PRIu64
, key
);
1120 assert(!channel
->monitor
);
1121 DBG("UST consumer snapshot channel %" PRIu64
, key
);
1123 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
1124 health_code_update();
1126 /* Lock stream because we are about to change its state. */
1127 pthread_mutex_lock(&stream
->lock
);
1128 stream
->net_seq_idx
= relayd_id
;
1131 ret
= consumer_send_relayd_stream(stream
, path
);
1136 ret
= utils_create_stream_file(path
, stream
->name
,
1137 stream
->chan
->tracefile_size
,
1138 stream
->tracefile_count_current
,
1139 stream
->uid
, stream
->gid
, NULL
);
1143 stream
->out_fd
= ret
;
1144 stream
->tracefile_size_current
= 0;
1146 DBG("UST consumer snapshot stream %s/%s (%" PRIu64
")", path
,
1147 stream
->name
, stream
->key
);
1151 * If tracing is active, we want to perform a "full" buffer flush.
1152 * Else, if quiescent, it has already been done by the prior stop.
1154 if (!stream
->quiescent
) {
1155 ustctl_flush_buffer(stream
->ustream
, 0);
1158 ret
= lttng_ustconsumer_take_snapshot(stream
);
1160 ERR("Taking UST snapshot");
1164 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
1166 ERR("Produced UST snapshot position");
1170 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
1172 ERR("Consumerd UST snapshot position");
1177 * The original value is sent back if max stream size is larger than
1178 * the possible size of the snapshot. Also, we assume that the session
1179 * daemon should never send a maximum stream size that is lower than
1182 consumed_pos
= consumer_get_consume_start_pos(consumed_pos
,
1183 produced_pos
, nb_packets_per_stream
,
1184 stream
->max_sb_size
);
1186 while ((long) (consumed_pos
- produced_pos
) < 0) {
1188 unsigned long len
, padded_len
;
1190 health_code_update();
1192 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
1194 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
1196 if (ret
!= -EAGAIN
) {
1197 PERROR("ustctl_get_subbuf snapshot");
1198 goto error_close_stream
;
1200 DBG("UST consumer get subbuf failed. Skipping it.");
1201 consumed_pos
+= stream
->max_sb_size
;
1202 stream
->chan
->lost_packets
++;
1206 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
1208 ERR("Snapshot ustctl_get_subbuf_size");
1209 goto error_put_subbuf
;
1212 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
1214 ERR("Snapshot ustctl_get_padded_subbuf_size");
1215 goto error_put_subbuf
;
1218 read_len
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, len
,
1219 padded_len
- len
, NULL
);
1221 if (read_len
!= len
) {
1223 goto error_put_subbuf
;
1226 if (read_len
!= padded_len
) {
1228 goto error_put_subbuf
;
1232 ret
= ustctl_put_subbuf(stream
->ustream
);
1234 ERR("Snapshot ustctl_put_subbuf");
1235 goto error_close_stream
;
1237 consumed_pos
+= stream
->max_sb_size
;
1240 /* Simply close the stream so we can use it on the next snapshot. */
1241 consumer_stream_close(stream
);
1242 pthread_mutex_unlock(&stream
->lock
);
1249 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
1250 ERR("Snapshot ustctl_put_subbuf");
1253 consumer_stream_close(stream
);
1255 pthread_mutex_unlock(&stream
->lock
);
1262 * Receive the metadata updates from the sessiond. Supports receiving
1263 * overlapping metadata, but is needs to always belong to a contiguous
1264 * range starting from 0.
1265 * Be careful about the locks held when calling this function: it needs
1266 * the metadata cache flush to concurrently progress in order to
1269 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
1270 uint64_t len
, uint64_t version
,
1271 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
1273 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1276 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
1278 metadata_str
= zmalloc(len
* sizeof(char));
1279 if (!metadata_str
) {
1280 PERROR("zmalloc metadata string");
1281 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
1285 health_code_update();
1287 /* Receive metadata string. */
1288 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1290 /* Session daemon is dead so return gracefully. */
1295 health_code_update();
1297 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1298 ret
= consumer_metadata_cache_write(channel
, offset
, len
, version
,
1301 /* Unable to handle metadata. Notify session daemon. */
1302 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1304 * Skip metadata flush on write error since the offset and len might
1305 * not have been updated which could create an infinite loop below when
1306 * waiting for the metadata cache to be flushed.
1308 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1311 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1316 while (consumer_metadata_cache_flushed(channel
, offset
+ len
, timer
)) {
1317 DBG("Waiting for metadata to be flushed");
1319 health_code_update();
1321 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1331 * Receive command from session daemon and process it.
1333 * Return 1 on success else a negative value or 0.
1335 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1336 int sock
, struct pollfd
*consumer_sockpoll
)
1339 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1340 struct lttcomm_consumer_msg msg
;
1341 struct lttng_consumer_channel
*channel
= NULL
;
1343 health_code_update();
1345 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1346 if (ret
!= sizeof(msg
)) {
1347 DBG("Consumer received unexpected message size %zd (expects %zu)",
1350 * The ret value might 0 meaning an orderly shutdown but this is ok
1351 * since the caller handles this.
1354 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1360 health_code_update();
1363 assert(msg
.cmd_type
!= LTTNG_CONSUMER_STOP
);
1365 health_code_update();
1367 /* relayd needs RCU read-side lock */
1370 switch (msg
.cmd_type
) {
1371 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1373 /* Session daemon status message are handled in the following call. */
1374 consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1375 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1376 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
,
1377 msg
.u
.relayd_sock
.relayd_session_id
);
1380 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1382 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1383 struct consumer_relayd_sock_pair
*relayd
;
1385 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1387 /* Get relayd reference if exists. */
1388 relayd
= consumer_find_relayd(index
);
1389 if (relayd
== NULL
) {
1390 DBG("Unable to find relayd %" PRIu64
, index
);
1391 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
1395 * Each relayd socket pair has a refcount of stream attached to it
1396 * which tells if the relayd is still active or not depending on the
1399 * This will set the destroy flag of the relayd object and destroy it
1400 * if the refcount reaches zero when called.
1402 * The destroy can happen either here or when a stream fd hangs up.
1405 consumer_flag_relayd_for_destroy(relayd
);
1408 goto end_msg_sessiond
;
1410 case LTTNG_CONSUMER_UPDATE_STREAM
:
1415 case LTTNG_CONSUMER_DATA_PENDING
:
1417 int ret
, is_data_pending
;
1418 uint64_t id
= msg
.u
.data_pending
.session_id
;
1420 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1422 is_data_pending
= consumer_data_pending(id
);
1424 /* Send back returned value to session daemon */
1425 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1426 sizeof(is_data_pending
));
1428 DBG("Error when sending the data pending ret code: %d", ret
);
1433 * No need to send back a status message since the data pending
1434 * returned value is the response.
1438 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1441 struct ustctl_consumer_channel_attr attr
;
1443 /* Create a plain object and reserve a channel key. */
1444 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
1445 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
1446 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
1447 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
1448 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1449 msg
.u
.ask_channel
.tracefile_size
,
1450 msg
.u
.ask_channel
.tracefile_count
,
1451 msg
.u
.ask_channel
.session_id_per_pid
,
1452 msg
.u
.ask_channel
.monitor
,
1453 msg
.u
.ask_channel
.live_timer_interval
,
1454 msg
.u
.ask_channel
.root_shm_path
,
1455 msg
.u
.ask_channel
.shm_path
);
1457 goto end_channel_error
;
1461 * Assign UST application UID to the channel. This value is ignored for
1462 * per PID buffers. This is specific to UST thus setting this after the
1465 channel
->ust_app_uid
= msg
.u
.ask_channel
.ust_app_uid
;
1467 /* Build channel attributes from received message. */
1468 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1469 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1470 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1471 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1472 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1473 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1474 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1475 attr
.blocking_timeout
= msg
.u
.ask_channel
.blocking_timeout
;
1477 /* Match channel buffer type to the UST abi. */
1478 switch (msg
.u
.ask_channel
.output
) {
1479 case LTTNG_EVENT_MMAP
:
1481 attr
.output
= LTTNG_UST_MMAP
;
1485 /* Translate and save channel type. */
1486 switch (msg
.u
.ask_channel
.type
) {
1487 case LTTNG_UST_CHAN_PER_CPU
:
1488 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1489 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1491 * Set refcount to 1 for owner. Below, we will
1492 * pass ownership to the
1493 * consumer_thread_channel_poll() thread.
1495 channel
->refcount
= 1;
1497 case LTTNG_UST_CHAN_METADATA
:
1498 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1499 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1506 health_code_update();
1508 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
1510 goto end_channel_error
;
1513 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1514 ret
= consumer_metadata_cache_allocate(channel
);
1516 ERR("Allocating metadata cache");
1517 goto end_channel_error
;
1519 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1520 attr
.switch_timer_interval
= 0;
1522 int monitor_start_ret
;
1524 consumer_timer_live_start(channel
,
1525 msg
.u
.ask_channel
.live_timer_interval
);
1526 monitor_start_ret
= consumer_timer_monitor_start(
1528 msg
.u
.ask_channel
.monitor_timer_interval
);
1529 if (monitor_start_ret
< 0) {
1530 ERR("Starting channel monitoring timer failed");
1531 goto end_channel_error
;
1535 health_code_update();
1538 * Add the channel to the internal state AFTER all streams were created
1539 * and successfully sent to session daemon. This way, all streams must
1540 * be ready before this channel is visible to the threads.
1541 * If add_channel succeeds, ownership of the channel is
1542 * passed to consumer_thread_channel_poll().
1544 ret
= add_channel(channel
, ctx
);
1546 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1547 if (channel
->switch_timer_enabled
== 1) {
1548 consumer_timer_switch_stop(channel
);
1550 consumer_metadata_cache_destroy(channel
);
1552 if (channel
->live_timer_enabled
== 1) {
1553 consumer_timer_live_stop(channel
);
1555 if (channel
->monitor_timer_enabled
== 1) {
1556 consumer_timer_monitor_stop(channel
);
1558 goto end_channel_error
;
1561 health_code_update();
1564 * Channel and streams are now created. Inform the session daemon that
1565 * everything went well and should wait to receive the channel and
1566 * streams with ustctl API.
1568 ret
= consumer_send_status_channel(sock
, channel
);
1571 * There is probably a problem on the socket.
1578 case LTTNG_CONSUMER_GET_CHANNEL
:
1580 int ret
, relayd_err
= 0;
1581 uint64_t key
= msg
.u
.get_channel
.key
;
1582 struct lttng_consumer_channel
*channel
;
1584 channel
= consumer_find_channel(key
);
1586 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1587 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1588 goto end_msg_sessiond
;
1591 health_code_update();
1593 /* Send everything to sessiond. */
1594 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1598 * We were unable to send to the relayd the stream so avoid
1599 * sending back a fatal error to the thread since this is OK
1600 * and the consumer can continue its work. The above call
1601 * has sent the error status message to the sessiond.
1606 * The communicaton was broken hence there is a bad state between
1607 * the consumer and sessiond so stop everything.
1612 health_code_update();
1615 * In no monitor mode, the streams ownership is kept inside the channel
1616 * so don't send them to the data thread.
1618 if (!channel
->monitor
) {
1619 goto end_msg_sessiond
;
1622 ret
= send_streams_to_thread(channel
, ctx
);
1625 * If we are unable to send the stream to the thread, there is
1626 * a big problem so just stop everything.
1630 /* List MUST be empty after or else it could be reused. */
1631 assert(cds_list_empty(&channel
->streams
.head
));
1632 goto end_msg_sessiond
;
1634 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1636 uint64_t key
= msg
.u
.destroy_channel
.key
;
1639 * Only called if streams have not been sent to stream
1640 * manager thread. However, channel has been sent to
1641 * channel manager thread.
1643 notify_thread_del_channel(ctx
, key
);
1644 goto end_msg_sessiond
;
1646 case LTTNG_CONSUMER_CLOSE_METADATA
:
1650 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1655 goto end_msg_sessiond
;
1657 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1661 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1666 goto end_msg_sessiond
;
1668 case LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL
:
1672 ret
= clear_quiescent_channel(
1673 msg
.u
.clear_quiescent_channel
.key
);
1678 goto end_msg_sessiond
;
1680 case LTTNG_CONSUMER_PUSH_METADATA
:
1683 uint64_t len
= msg
.u
.push_metadata
.len
;
1684 uint64_t key
= msg
.u
.push_metadata
.key
;
1685 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1686 uint64_t version
= msg
.u
.push_metadata
.version
;
1687 struct lttng_consumer_channel
*channel
;
1689 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1692 channel
= consumer_find_channel(key
);
1695 * This is possible if the metadata creation on the consumer side
1696 * is in flight vis-a-vis a concurrent push metadata from the
1697 * session daemon. Simply return that the channel failed and the
1698 * session daemon will handle that message correctly considering
1699 * that this race is acceptable thus the DBG() statement here.
1701 DBG("UST consumer push metadata %" PRIu64
" not found", key
);
1702 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1703 goto end_msg_sessiond
;
1706 health_code_update();
1710 * There is nothing to receive. We have simply
1711 * checked whether the channel can be found.
1713 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1714 goto end_msg_sessiond
;
1717 /* Tell session daemon we are ready to receive the metadata. */
1718 ret
= consumer_send_status_msg(sock
, LTTCOMM_CONSUMERD_SUCCESS
);
1720 /* Somehow, the session daemon is not responding anymore. */
1724 health_code_update();
1726 /* Wait for more data. */
1727 health_poll_entry();
1728 ret
= lttng_consumer_poll_socket(consumer_sockpoll
);
1734 health_code_update();
1736 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1737 len
, version
, channel
, 0, 1);
1739 /* error receiving from sessiond */
1743 goto end_msg_sessiond
;
1746 case LTTNG_CONSUMER_SETUP_METADATA
:
1750 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1754 goto end_msg_sessiond
;
1756 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1758 if (msg
.u
.snapshot_channel
.metadata
) {
1759 ret
= snapshot_metadata(msg
.u
.snapshot_channel
.key
,
1760 msg
.u
.snapshot_channel
.pathname
,
1761 msg
.u
.snapshot_channel
.relayd_id
,
1764 ERR("Snapshot metadata failed");
1765 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1768 ret
= snapshot_channel(msg
.u
.snapshot_channel
.key
,
1769 msg
.u
.snapshot_channel
.pathname
,
1770 msg
.u
.snapshot_channel
.relayd_id
,
1771 msg
.u
.snapshot_channel
.nb_packets_per_stream
,
1774 ERR("Snapshot channel failed");
1775 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1779 health_code_update();
1780 ret
= consumer_send_status_msg(sock
, ret_code
);
1782 /* Somehow, the session daemon is not responding anymore. */
1785 health_code_update();
1788 case LTTNG_CONSUMER_DISCARDED_EVENTS
:
1791 uint64_t discarded_events
;
1792 struct lttng_ht_iter iter
;
1793 struct lttng_ht
*ht
;
1794 struct lttng_consumer_stream
*stream
;
1795 uint64_t id
= msg
.u
.discarded_events
.session_id
;
1796 uint64_t key
= msg
.u
.discarded_events
.channel_key
;
1798 DBG("UST consumer discarded events command for session id %"
1801 pthread_mutex_lock(&consumer_data
.lock
);
1803 ht
= consumer_data
.stream_list_ht
;
1806 * We only need a reference to the channel, but they are not
1807 * directly indexed, so we just use the first matching stream
1808 * to extract the information we need, we default to 0 if not
1809 * found (no events are dropped if the channel is not yet in
1812 discarded_events
= 0;
1813 cds_lfht_for_each_entry_duplicate(ht
->ht
,
1814 ht
->hash_fct(&id
, lttng_ht_seed
),
1816 &iter
.iter
, stream
, node_session_id
.node
) {
1817 if (stream
->chan
->key
== key
) {
1818 discarded_events
= stream
->chan
->discarded_events
;
1822 pthread_mutex_unlock(&consumer_data
.lock
);
1825 DBG("UST consumer discarded events command for session id %"
1826 PRIu64
", channel key %" PRIu64
, id
, key
);
1828 health_code_update();
1830 /* Send back returned value to session daemon */
1831 ret
= lttcomm_send_unix_sock(sock
, &discarded_events
, sizeof(discarded_events
));
1833 PERROR("send discarded events");
1839 case LTTNG_CONSUMER_LOST_PACKETS
:
1842 uint64_t lost_packets
;
1843 struct lttng_ht_iter iter
;
1844 struct lttng_ht
*ht
;
1845 struct lttng_consumer_stream
*stream
;
1846 uint64_t id
= msg
.u
.lost_packets
.session_id
;
1847 uint64_t key
= msg
.u
.lost_packets
.channel_key
;
1849 DBG("UST consumer lost packets command for session id %"
1852 pthread_mutex_lock(&consumer_data
.lock
);
1854 ht
= consumer_data
.stream_list_ht
;
1857 * We only need a reference to the channel, but they are not
1858 * directly indexed, so we just use the first matching stream
1859 * to extract the information we need, we default to 0 if not
1860 * found (no packets lost if the channel is not yet in use).
1863 cds_lfht_for_each_entry_duplicate(ht
->ht
,
1864 ht
->hash_fct(&id
, lttng_ht_seed
),
1866 &iter
.iter
, stream
, node_session_id
.node
) {
1867 if (stream
->chan
->key
== key
) {
1868 lost_packets
= stream
->chan
->lost_packets
;
1872 pthread_mutex_unlock(&consumer_data
.lock
);
1875 DBG("UST consumer lost packets command for session id %"
1876 PRIu64
", channel key %" PRIu64
, id
, key
);
1878 health_code_update();
1880 /* Send back returned value to session daemon */
1881 ret
= lttcomm_send_unix_sock(sock
, &lost_packets
,
1882 sizeof(lost_packets
));
1884 PERROR("send lost packets");
1890 case LTTNG_CONSUMER_SET_CHANNEL_MONITOR_PIPE
:
1892 int channel_monitor_pipe
;
1894 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1895 /* Successfully received the command's type. */
1896 ret
= consumer_send_status_msg(sock
, ret_code
);
1901 ret
= lttcomm_recv_fds_unix_sock(sock
, &channel_monitor_pipe
,
1903 if (ret
!= sizeof(channel_monitor_pipe
)) {
1904 ERR("Failed to receive channel monitor pipe");
1908 DBG("Received channel monitor pipe (%d)", channel_monitor_pipe
);
1909 ret
= consumer_timer_thread_set_channel_monitor_pipe(
1910 channel_monitor_pipe
);
1914 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1915 /* Set the pipe as non-blocking. */
1916 ret
= fcntl(channel_monitor_pipe
, F_GETFL
, 0);
1918 PERROR("fcntl get flags of the channel monitoring pipe");
1923 ret
= fcntl(channel_monitor_pipe
, F_SETFL
,
1924 flags
| O_NONBLOCK
);
1926 PERROR("fcntl set O_NONBLOCK flag of the channel monitoring pipe");
1929 DBG("Channel monitor pipe set as non-blocking");
1931 ret_code
= LTTCOMM_CONSUMERD_ALREADY_SET
;
1933 goto end_msg_sessiond
;
1942 health_code_update();
1945 * Return 1 to indicate success since the 0 value can be a socket
1946 * shutdown during the recv() or send() call.
1952 * The returned value here is not useful since either way we'll return 1 to
1953 * the caller because the session daemon socket management is done
1954 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1956 ret
= consumer_send_status_msg(sock
, ret_code
);
1962 health_code_update();
1968 * Free channel here since no one has a reference to it. We don't
1969 * free after that because a stream can store this pointer.
1971 destroy_channel(channel
);
1973 /* We have to send a status channel message indicating an error. */
1974 ret
= consumer_send_status_channel(sock
, NULL
);
1976 /* Stop everything if session daemon can not be notified. */
1981 health_code_update();
1986 /* This will issue a consumer stop. */
1991 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1992 * compiled out, we isolate it in this library.
1994 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1998 assert(stream
->ustream
);
2000 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
2004 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
2005 * compiled out, we isolate it in this library.
2007 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
2010 assert(stream
->ustream
);
2012 return ustctl_get_mmap_base(stream
->ustream
);
2016 * Take a snapshot for a specific stream.
2018 * Returns 0 on success, < 0 on error
2020 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
2023 assert(stream
->ustream
);
2025 return ustctl_snapshot(stream
->ustream
);
2029 * Sample consumed and produced positions for a specific stream.
2031 * Returns 0 on success, < 0 on error.
2033 int lttng_ustconsumer_sample_snapshot_positions(
2034 struct lttng_consumer_stream
*stream
)
2037 assert(stream
->ustream
);
2039 return ustctl_snapshot_sample_positions(stream
->ustream
);
2043 * Get the produced position
2045 * Returns 0 on success, < 0 on error
2047 int lttng_ustconsumer_get_produced_snapshot(
2048 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
2051 assert(stream
->ustream
);
2054 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
2058 * Get the consumed position
2060 * Returns 0 on success, < 0 on error
2062 int lttng_ustconsumer_get_consumed_snapshot(
2063 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
2066 assert(stream
->ustream
);
2069 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
2072 void lttng_ustconsumer_flush_buffer(struct lttng_consumer_stream
*stream
,
2076 assert(stream
->ustream
);
2078 ustctl_flush_buffer(stream
->ustream
, producer
);
2081 int lttng_ustconsumer_get_current_timestamp(
2082 struct lttng_consumer_stream
*stream
, uint64_t *ts
)
2085 assert(stream
->ustream
);
2088 return ustctl_get_current_timestamp(stream
->ustream
, ts
);
2091 int lttng_ustconsumer_get_sequence_number(
2092 struct lttng_consumer_stream
*stream
, uint64_t *seq
)
2095 assert(stream
->ustream
);
2098 return ustctl_get_sequence_number(stream
->ustream
, seq
);
2102 * Called when the stream signals the consumer that it has hung up.
2104 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
2107 assert(stream
->ustream
);
2109 pthread_mutex_lock(&stream
->lock
);
2110 if (!stream
->quiescent
) {
2111 ustctl_flush_buffer(stream
->ustream
, 0);
2112 stream
->quiescent
= true;
2114 pthread_mutex_unlock(&stream
->lock
);
2115 stream
->hangup_flush_done
= 1;
2118 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
2123 assert(chan
->uchan
);
2125 if (chan
->switch_timer_enabled
== 1) {
2126 consumer_timer_switch_stop(chan
);
2128 for (i
= 0; i
< chan
->nr_stream_fds
; i
++) {
2131 ret
= close(chan
->stream_fds
[i
]);
2135 if (chan
->shm_path
[0]) {
2136 char shm_path
[PATH_MAX
];
2138 ret
= get_stream_shm_path(shm_path
, chan
->shm_path
, i
);
2140 ERR("Cannot get stream shm path");
2142 ret
= run_as_unlink(shm_path
, chan
->uid
, chan
->gid
);
2144 PERROR("unlink %s", shm_path
);
2150 void lttng_ustconsumer_free_channel(struct lttng_consumer_channel
*chan
)
2153 assert(chan
->uchan
);
2155 consumer_metadata_cache_destroy(chan
);
2156 ustctl_destroy_channel(chan
->uchan
);
2157 /* Try to rmdir all directories under shm_path root. */
2158 if (chan
->root_shm_path
[0]) {
2159 (void) run_as_rmdir_recursive(chan
->root_shm_path
,
2160 chan
->uid
, chan
->gid
);
2162 free(chan
->stream_fds
);
2165 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
2168 assert(stream
->ustream
);
2170 if (stream
->chan
->switch_timer_enabled
== 1) {
2171 consumer_timer_switch_stop(stream
->chan
);
2173 ustctl_destroy_stream(stream
->ustream
);
2176 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream
*stream
)
2179 assert(stream
->ustream
);
2181 return ustctl_stream_get_wakeup_fd(stream
->ustream
);
2184 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream
*stream
)
2187 assert(stream
->ustream
);
2189 return ustctl_stream_close_wakeup_fd(stream
->ustream
);
2193 * Populate index values of a UST stream. Values are set in big endian order.
2195 * Return 0 on success or else a negative value.
2197 static int get_index_values(struct ctf_packet_index
*index
,
2198 struct ustctl_consumer_stream
*ustream
)
2202 ret
= ustctl_get_timestamp_begin(ustream
, &index
->timestamp_begin
);
2204 PERROR("ustctl_get_timestamp_begin");
2207 index
->timestamp_begin
= htobe64(index
->timestamp_begin
);
2209 ret
= ustctl_get_timestamp_end(ustream
, &index
->timestamp_end
);
2211 PERROR("ustctl_get_timestamp_end");
2214 index
->timestamp_end
= htobe64(index
->timestamp_end
);
2216 ret
= ustctl_get_events_discarded(ustream
, &index
->events_discarded
);
2218 PERROR("ustctl_get_events_discarded");
2221 index
->events_discarded
= htobe64(index
->events_discarded
);
2223 ret
= ustctl_get_content_size(ustream
, &index
->content_size
);
2225 PERROR("ustctl_get_content_size");
2228 index
->content_size
= htobe64(index
->content_size
);
2230 ret
= ustctl_get_packet_size(ustream
, &index
->packet_size
);
2232 PERROR("ustctl_get_packet_size");
2235 index
->packet_size
= htobe64(index
->packet_size
);
2237 ret
= ustctl_get_stream_id(ustream
, &index
->stream_id
);
2239 PERROR("ustctl_get_stream_id");
2242 index
->stream_id
= htobe64(index
->stream_id
);
2244 ret
= ustctl_get_instance_id(ustream
, &index
->stream_instance_id
);
2246 PERROR("ustctl_get_instance_id");
2249 index
->stream_instance_id
= htobe64(index
->stream_instance_id
);
2251 ret
= ustctl_get_sequence_number(ustream
, &index
->packet_seq_num
);
2253 PERROR("ustctl_get_sequence_number");
2256 index
->packet_seq_num
= htobe64(index
->packet_seq_num
);
2263 void metadata_stream_reset_cache(struct lttng_consumer_stream
*stream
,
2264 struct consumer_metadata_cache
*cache
)
2266 DBG("Metadata stream update to version %" PRIu64
,
2268 stream
->ust_metadata_pushed
= 0;
2269 stream
->metadata_version
= cache
->version
;
2270 stream
->reset_metadata_flag
= 1;
2274 * Check if the version of the metadata stream and metadata cache match.
2275 * If the cache got updated, reset the metadata stream.
2276 * The stream lock and metadata cache lock MUST be held.
2277 * Return 0 on success, a negative value on error.
2280 int metadata_stream_check_version(struct lttng_consumer_stream
*stream
)
2283 struct consumer_metadata_cache
*cache
= stream
->chan
->metadata_cache
;
2285 if (cache
->version
== stream
->metadata_version
) {
2288 metadata_stream_reset_cache(stream
, cache
);
2295 * Write up to one packet from the metadata cache to the channel.
2297 * Returns the number of bytes pushed in the cache, or a negative value
2301 int commit_one_metadata_packet(struct lttng_consumer_stream
*stream
)
2306 pthread_mutex_lock(&stream
->chan
->metadata_cache
->lock
);
2307 ret
= metadata_stream_check_version(stream
);
2311 if (stream
->chan
->metadata_cache
->max_offset
2312 == stream
->ust_metadata_pushed
) {
2317 write_len
= ustctl_write_one_packet_to_channel(stream
->chan
->uchan
,
2318 &stream
->chan
->metadata_cache
->data
[stream
->ust_metadata_pushed
],
2319 stream
->chan
->metadata_cache
->max_offset
2320 - stream
->ust_metadata_pushed
);
2321 assert(write_len
!= 0);
2322 if (write_len
< 0) {
2323 ERR("Writing one metadata packet");
2327 stream
->ust_metadata_pushed
+= write_len
;
2329 assert(stream
->chan
->metadata_cache
->max_offset
>=
2330 stream
->ust_metadata_pushed
);
2334 pthread_mutex_unlock(&stream
->chan
->metadata_cache
->lock
);
2340 * Sync metadata meaning request them to the session daemon and snapshot to the
2341 * metadata thread can consumer them.
2343 * Metadata stream lock is held here, but we need to release it when
2344 * interacting with sessiond, else we cause a deadlock with live
2345 * awaiting on metadata to be pushed out.
2347 * Return 0 if new metadatda is available, EAGAIN if the metadata stream
2348 * is empty or a negative value on error.
2350 int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data
*ctx
,
2351 struct lttng_consumer_stream
*metadata
)
2359 pthread_mutex_unlock(&metadata
->lock
);
2361 * Request metadata from the sessiond, but don't wait for the flush
2362 * because we locked the metadata thread.
2364 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata
->chan
, 0, 0);
2365 pthread_mutex_lock(&metadata
->lock
);
2370 ret
= commit_one_metadata_packet(metadata
);
2373 } else if (ret
> 0) {
2377 ustctl_flush_buffer(metadata
->ustream
, 1);
2378 ret
= ustctl_snapshot(metadata
->ustream
);
2380 if (errno
!= EAGAIN
) {
2381 ERR("Sync metadata, taking UST snapshot");
2384 DBG("No new metadata when syncing them.");
2385 /* No new metadata, exit. */
2391 * After this flush, we still need to extract metadata.
2402 * Return 0 on success else a negative value.
2404 static int notify_if_more_data(struct lttng_consumer_stream
*stream
,
2405 struct lttng_consumer_local_data
*ctx
)
2408 struct ustctl_consumer_stream
*ustream
;
2413 ustream
= stream
->ustream
;
2416 * First, we are going to check if there is a new subbuffer available
2417 * before reading the stream wait_fd.
2419 /* Get the next subbuffer */
2420 ret
= ustctl_get_next_subbuf(ustream
);
2422 /* No more data found, flag the stream. */
2423 stream
->has_data
= 0;
2428 ret
= ustctl_put_subbuf(ustream
);
2431 /* This stream still has data. Flag it and wake up the data thread. */
2432 stream
->has_data
= 1;
2434 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !ctx
->has_wakeup
) {
2437 writelen
= lttng_pipe_write(ctx
->consumer_wakeup_pipe
, "!", 1);
2438 if (writelen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2443 /* The wake up pipe has been notified. */
2444 ctx
->has_wakeup
= 1;
2453 int update_stream_stats(struct lttng_consumer_stream
*stream
)
2456 uint64_t seq
, discarded
;
2458 ret
= ustctl_get_sequence_number(stream
->ustream
, &seq
);
2460 PERROR("ustctl_get_sequence_number");
2464 * Start the sequence when we extract the first packet in case we don't
2465 * start at 0 (for example if a consumer is not connected to the
2466 * session immediately after the beginning).
2468 if (stream
->last_sequence_number
== -1ULL) {
2469 stream
->last_sequence_number
= seq
;
2470 } else if (seq
> stream
->last_sequence_number
) {
2471 stream
->chan
->lost_packets
+= seq
-
2472 stream
->last_sequence_number
- 1;
2474 /* seq <= last_sequence_number */
2475 ERR("Sequence number inconsistent : prev = %" PRIu64
2476 ", current = %" PRIu64
,
2477 stream
->last_sequence_number
, seq
);
2481 stream
->last_sequence_number
= seq
;
2483 ret
= ustctl_get_events_discarded(stream
->ustream
, &discarded
);
2485 PERROR("kernctl_get_events_discarded");
2488 if (discarded
< stream
->last_discarded_events
) {
2490 * Overflow has occurred. We assume only one wrap-around
2493 stream
->chan
->discarded_events
+=
2494 (1ULL << (CAA_BITS_PER_LONG
- 1)) -
2495 stream
->last_discarded_events
+ discarded
;
2497 stream
->chan
->discarded_events
+= discarded
-
2498 stream
->last_discarded_events
;
2500 stream
->last_discarded_events
= discarded
;
2508 * Read subbuffer from the given stream.
2510 * Stream lock MUST be acquired.
2512 * Return 0 on success else a negative value.
2514 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
2515 struct lttng_consumer_local_data
*ctx
)
2517 unsigned long len
, subbuf_size
, padding
;
2518 int err
, write_index
= 1;
2520 struct ustctl_consumer_stream
*ustream
;
2521 struct ctf_packet_index index
;
2524 assert(stream
->ustream
);
2527 DBG("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
2530 /* Ease our life for what's next. */
2531 ustream
= stream
->ustream
;
2534 * We can consume the 1 byte written into the wait_fd by UST. Don't trigger
2535 * error if we cannot read this one byte (read returns 0), or if the error
2536 * is EAGAIN or EWOULDBLOCK.
2538 * This is only done when the stream is monitored by a thread, before the
2539 * flush is done after a hangup and if the stream is not flagged with data
2540 * since there might be nothing to consume in the wait fd but still have
2541 * data available flagged by the consumer wake up pipe.
2543 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !stream
->has_data
) {
2547 readlen
= lttng_read(stream
->wait_fd
, &dummy
, 1);
2548 if (readlen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2555 /* Get the next subbuffer */
2556 err
= ustctl_get_next_subbuf(ustream
);
2559 * Populate metadata info if the existing info has
2560 * already been read.
2562 if (stream
->metadata_flag
) {
2563 ret
= commit_one_metadata_packet(stream
);
2567 ustctl_flush_buffer(stream
->ustream
, 1);
2571 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
2573 * This is a debug message even for single-threaded consumer,
2574 * because poll() have more relaxed criterions than get subbuf,
2575 * so get_subbuf may fail for short race windows where poll()
2576 * would issue wakeups.
2578 DBG("Reserving sub buffer failed (everything is normal, "
2579 "it is due to concurrency) [ret: %d]", err
);
2582 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
2584 if (!stream
->metadata_flag
) {
2585 index
.offset
= htobe64(stream
->out_fd_offset
);
2586 ret
= get_index_values(&index
, ustream
);
2588 err
= ustctl_put_subbuf(ustream
);
2593 /* Update the stream's sequence and discarded events count. */
2594 ret
= update_stream_stats(stream
);
2596 PERROR("kernctl_get_events_discarded");
2597 err
= ustctl_put_subbuf(ustream
);
2605 /* Get the full padded subbuffer size */
2606 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
2609 /* Get subbuffer data size (without padding) */
2610 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
2613 /* Make sure we don't get a subbuffer size bigger than the padded */
2614 assert(len
>= subbuf_size
);
2616 padding
= len
- subbuf_size
;
2617 /* write the subbuffer to the tracefile */
2618 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
, &index
);
2620 * The mmap operation should write subbuf_size amount of data when network
2621 * streaming or the full padding (len) size when we are _not_ streaming.
2623 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
2624 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
2626 * Display the error but continue processing to try to release the
2627 * subbuffer. This is a DBG statement since any unexpected kill or
2628 * signal, the application gets unregistered, relayd gets closed or
2629 * anything that affects the buffer lifetime will trigger this error.
2630 * So, for the sake of the user, don't print this error since it can
2631 * happen and it is OK with the code flow.
2633 DBG("Error writing to tracefile "
2634 "(ret: %ld != len: %lu != subbuf_size: %lu)",
2635 ret
, len
, subbuf_size
);
2638 err
= ustctl_put_next_subbuf(ustream
);
2642 * This will consumer the byte on the wait_fd if and only if there is not
2643 * next subbuffer to be acquired.
2645 if (!stream
->metadata_flag
) {
2646 ret
= notify_if_more_data(stream
, ctx
);
2652 /* Write index if needed. */
2657 if (stream
->chan
->live_timer_interval
&& !stream
->metadata_flag
) {
2659 * In live, block until all the metadata is sent.
2661 pthread_mutex_lock(&stream
->metadata_timer_lock
);
2662 assert(!stream
->missed_metadata_flush
);
2663 stream
->waiting_on_metadata
= true;
2664 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2666 err
= consumer_stream_sync_metadata(ctx
, stream
->session_id
);
2668 pthread_mutex_lock(&stream
->metadata_timer_lock
);
2669 stream
->waiting_on_metadata
= false;
2670 if (stream
->missed_metadata_flush
) {
2671 stream
->missed_metadata_flush
= false;
2672 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2673 (void) consumer_flush_ust_index(stream
);
2675 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2683 assert(!stream
->metadata_flag
);
2684 err
= consumer_stream_write_index(stream
, &index
);
2694 * Called when a stream is created.
2696 * Return 0 on success or else a negative value.
2698 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
2704 /* Don't create anything if this is set for streaming. */
2705 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
) {
2706 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
2707 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
2708 stream
->uid
, stream
->gid
, NULL
);
2712 stream
->out_fd
= ret
;
2713 stream
->tracefile_size_current
= 0;
2715 if (!stream
->metadata_flag
) {
2716 struct lttng_index_file
*index_file
;
2718 index_file
= lttng_index_file_create(stream
->chan
->pathname
,
2719 stream
->name
, stream
->uid
, stream
->gid
,
2720 stream
->chan
->tracefile_size
,
2721 stream
->tracefile_count_current
,
2722 CTF_INDEX_MAJOR
, CTF_INDEX_MINOR
);
2726 assert(!stream
->index_file
);
2727 stream
->index_file
= index_file
;
2737 * Check if data is still being extracted from the buffers for a specific
2738 * stream. Consumer data lock MUST be acquired before calling this function
2739 * and the stream lock.
2741 * Return 1 if the traced data are still getting read else 0 meaning that the
2742 * data is available for trace viewer reading.
2744 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
2749 assert(stream
->ustream
);
2751 DBG("UST consumer checking data pending");
2753 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
2758 if (stream
->chan
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
2759 uint64_t contiguous
, pushed
;
2761 /* Ease our life a bit. */
2762 contiguous
= stream
->chan
->metadata_cache
->max_offset
;
2763 pushed
= stream
->ust_metadata_pushed
;
2766 * We can simply check whether all contiguously available data
2767 * has been pushed to the ring buffer, since the push operation
2768 * is performed within get_next_subbuf(), and because both
2769 * get_next_subbuf() and put_next_subbuf() are issued atomically
2770 * thanks to the stream lock within
2771 * lttng_ustconsumer_read_subbuffer(). This basically means that
2772 * whetnever ust_metadata_pushed is incremented, the associated
2773 * metadata has been consumed from the metadata stream.
2775 DBG("UST consumer metadata pending check: contiguous %" PRIu64
" vs pushed %" PRIu64
,
2776 contiguous
, pushed
);
2777 assert(((int64_t) (contiguous
- pushed
)) >= 0);
2778 if ((contiguous
!= pushed
) ||
2779 (((int64_t) contiguous
- pushed
) > 0 || contiguous
== 0)) {
2780 ret
= 1; /* Data is pending */
2784 ret
= ustctl_get_next_subbuf(stream
->ustream
);
2787 * There is still data so let's put back this
2790 ret
= ustctl_put_subbuf(stream
->ustream
);
2792 ret
= 1; /* Data is pending */
2797 /* Data is NOT pending so ready to be read. */
2805 * Stop a given metadata channel timer if enabled and close the wait fd which
2806 * is the poll pipe of the metadata stream.
2808 * This MUST be called with the metadata channel acquired.
2810 void lttng_ustconsumer_close_metadata(struct lttng_consumer_channel
*metadata
)
2815 assert(metadata
->type
== CONSUMER_CHANNEL_TYPE_METADATA
);
2817 DBG("Closing metadata channel key %" PRIu64
, metadata
->key
);
2819 if (metadata
->switch_timer_enabled
== 1) {
2820 consumer_timer_switch_stop(metadata
);
2823 if (!metadata
->metadata_stream
) {
2828 * Closing write side so the thread monitoring the stream wakes up if any
2829 * and clean the metadata stream.
2831 if (metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] >= 0) {
2832 ret
= close(metadata
->metadata_stream
->ust_metadata_poll_pipe
[1]);
2834 PERROR("closing metadata pipe write side");
2836 metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] = -1;
2844 * Close every metadata stream wait fd of the metadata hash table. This
2845 * function MUST be used very carefully so not to run into a race between the
2846 * metadata thread handling streams and this function closing their wait fd.
2848 * For UST, this is used when the session daemon hangs up. Its the metadata
2849 * producer so calling this is safe because we are assured that no state change
2850 * can occur in the metadata thread for the streams in the hash table.
2852 void lttng_ustconsumer_close_all_metadata(struct lttng_ht
*metadata_ht
)
2854 struct lttng_ht_iter iter
;
2855 struct lttng_consumer_stream
*stream
;
2857 assert(metadata_ht
);
2858 assert(metadata_ht
->ht
);
2860 DBG("UST consumer closing all metadata streams");
2863 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
2866 health_code_update();
2868 pthread_mutex_lock(&stream
->chan
->lock
);
2869 lttng_ustconsumer_close_metadata(stream
->chan
);
2870 pthread_mutex_unlock(&stream
->chan
->lock
);
2876 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
2880 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
2882 ERR("Unable to close wakeup fd");
2887 * Please refer to consumer-timer.c before adding any lock within this
2888 * function or any of its callees. Timers have a very strict locking
2889 * semantic with respect to teardown. Failure to respect this semantic
2890 * introduces deadlocks.
2892 * DON'T hold the metadata lock when calling this function, else this
2893 * can cause deadlock involving consumer awaiting for metadata to be
2894 * pushed out due to concurrent interaction with the session daemon.
2896 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
2897 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
2899 struct lttcomm_metadata_request_msg request
;
2900 struct lttcomm_consumer_msg msg
;
2901 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
2902 uint64_t len
, key
, offset
, version
;
2906 assert(channel
->metadata_cache
);
2908 memset(&request
, 0, sizeof(request
));
2910 /* send the metadata request to sessiond */
2911 switch (consumer_data
.type
) {
2912 case LTTNG_CONSUMER64_UST
:
2913 request
.bits_per_long
= 64;
2915 case LTTNG_CONSUMER32_UST
:
2916 request
.bits_per_long
= 32;
2919 request
.bits_per_long
= 0;
2923 request
.session_id
= channel
->session_id
;
2924 request
.session_id_per_pid
= channel
->session_id_per_pid
;
2926 * Request the application UID here so the metadata of that application can
2927 * be sent back. The channel UID corresponds to the user UID of the session
2928 * used for the rights on the stream file(s).
2930 request
.uid
= channel
->ust_app_uid
;
2931 request
.key
= channel
->key
;
2933 DBG("Sending metadata request to sessiond, session id %" PRIu64
2934 ", per-pid %" PRIu64
", app UID %u and channel key %" PRIu64
,
2935 request
.session_id
, request
.session_id_per_pid
, request
.uid
,
2938 pthread_mutex_lock(&ctx
->metadata_socket_lock
);
2940 health_code_update();
2942 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
2945 ERR("Asking metadata to sessiond");
2949 health_code_update();
2951 /* Receive the metadata from sessiond */
2952 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
2954 if (ret
!= sizeof(msg
)) {
2955 DBG("Consumer received unexpected message size %d (expects %zu)",
2957 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
2959 * The ret value might 0 meaning an orderly shutdown but this is ok
2960 * since the caller handles this.
2965 health_code_update();
2967 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
2968 /* No registry found */
2969 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2973 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
2974 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
2979 len
= msg
.u
.push_metadata
.len
;
2980 key
= msg
.u
.push_metadata
.key
;
2981 offset
= msg
.u
.push_metadata
.target_offset
;
2982 version
= msg
.u
.push_metadata
.version
;
2984 assert(key
== channel
->key
);
2986 DBG("No new metadata to receive for key %" PRIu64
, key
);
2989 health_code_update();
2991 /* Tell session daemon we are ready to receive the metadata. */
2992 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2993 LTTCOMM_CONSUMERD_SUCCESS
);
2994 if (ret
< 0 || len
== 0) {
2996 * Somehow, the session daemon is not responding anymore or there is
2997 * nothing to receive.
3002 health_code_update();
3004 ret
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
3005 key
, offset
, len
, version
, channel
, timer
, wait
);
3008 * Only send the status msg if the sessiond is alive meaning a positive
3011 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret
);
3016 health_code_update();
3018 pthread_mutex_unlock(&ctx
->metadata_socket_lock
);
3023 * Return the ustctl call for the get stream id.
3025 int lttng_ustconsumer_get_stream_id(struct lttng_consumer_stream
*stream
,
3026 uint64_t *stream_id
)
3031 return ustctl_get_stream_id(stream
->ustream
, stream_id
);