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 <bin/lttng-consumerd/health-consumerd.h>
36 #include <common/common.h>
37 #include <common/sessiond-comm/sessiond-comm.h>
38 #include <common/relayd/relayd.h>
39 #include <common/compat/fcntl.h>
40 #include <common/compat/endian.h>
41 #include <common/consumer/consumer-metadata-cache.h>
42 #include <common/consumer/consumer-stream.h>
43 #include <common/consumer/consumer-timer.h>
44 #include <common/utils.h>
45 #include <common/index/index.h>
47 #include "ust-consumer.h"
49 #define INT_MAX_STR_LEN 12 /* includes \0 */
51 extern struct lttng_consumer_global_data consumer_data
;
52 extern int consumer_poll_timeout
;
53 extern volatile int consumer_quit
;
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_recursive_rmdir(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 ustctl_flush_buffer(stream
->ustream
, 1);
778 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
779 * RCU read side lock MUST be acquired before calling this function.
781 * Return 0 on success else an LTTng error code.
783 static int close_metadata(uint64_t chan_key
)
786 struct lttng_consumer_channel
*channel
;
788 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
790 channel
= consumer_find_channel(chan_key
);
793 * This is possible if the metadata thread has issue a delete because
794 * the endpoint point of the stream hung up. There is no way the
795 * session daemon can know about it thus use a DBG instead of an actual
798 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
799 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
803 pthread_mutex_lock(&consumer_data
.lock
);
804 pthread_mutex_lock(&channel
->lock
);
806 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
810 lttng_ustconsumer_close_metadata(channel
);
813 pthread_mutex_unlock(&channel
->lock
);
814 pthread_mutex_unlock(&consumer_data
.lock
);
820 * RCU read side lock MUST be acquired before calling this function.
822 * Return 0 on success else an LTTng error code.
824 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
827 struct lttng_consumer_channel
*metadata
;
829 DBG("UST consumer setup metadata key %" PRIu64
, key
);
831 metadata
= consumer_find_channel(key
);
833 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
834 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
839 * In no monitor mode, the metadata channel has no stream(s) so skip the
840 * ownership transfer to the metadata thread.
842 if (!metadata
->monitor
) {
843 DBG("Metadata channel in no monitor");
849 * Send metadata stream to relayd if one available. Availability is
850 * known if the stream is still in the list of the channel.
852 if (cds_list_empty(&metadata
->streams
.head
)) {
853 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
854 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
855 goto error_no_stream
;
858 /* Send metadata stream to relayd if needed. */
859 if (metadata
->metadata_stream
->net_seq_idx
!= (uint64_t) -1ULL) {
860 ret
= consumer_send_relayd_stream(metadata
->metadata_stream
,
863 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
866 ret
= consumer_send_relayd_streams_sent(
867 metadata
->metadata_stream
->net_seq_idx
);
869 ret
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
874 ret
= send_streams_to_thread(metadata
, ctx
);
877 * If we are unable to send the stream to the thread, there is
878 * a big problem so just stop everything.
880 ret
= LTTCOMM_CONSUMERD_FATAL
;
883 /* List MUST be empty after or else it could be reused. */
884 assert(cds_list_empty(&metadata
->streams
.head
));
891 * Delete metadata channel on error. At this point, the metadata stream can
892 * NOT be monitored by the metadata thread thus having the guarantee that
893 * the stream is still in the local stream list of the channel. This call
894 * will make sure to clean that list.
896 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
897 cds_list_del(&metadata
->metadata_stream
->send_node
);
898 metadata
->metadata_stream
= NULL
;
905 * Snapshot the whole metadata.
907 * Returns 0 on success, < 0 on error
909 static int snapshot_metadata(uint64_t key
, char *path
, uint64_t relayd_id
,
910 struct lttng_consumer_local_data
*ctx
)
913 struct lttng_consumer_channel
*metadata_channel
;
914 struct lttng_consumer_stream
*metadata_stream
;
919 DBG("UST consumer snapshot metadata with key %" PRIu64
" at path %s",
924 metadata_channel
= consumer_find_channel(key
);
925 if (!metadata_channel
) {
926 ERR("UST snapshot metadata channel not found for key %" PRIu64
,
931 assert(!metadata_channel
->monitor
);
933 health_code_update();
936 * Ask the sessiond if we have new metadata waiting and update the
937 * consumer metadata cache.
939 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
, 0, 1);
944 health_code_update();
947 * The metadata stream is NOT created in no monitor mode when the channel
948 * is created on a sessiond ask channel command.
950 ret
= create_ust_streams(metadata_channel
, ctx
);
955 metadata_stream
= metadata_channel
->metadata_stream
;
956 assert(metadata_stream
);
958 if (relayd_id
!= (uint64_t) -1ULL) {
959 metadata_stream
->net_seq_idx
= relayd_id
;
960 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
965 ret
= utils_create_stream_file(path
, metadata_stream
->name
,
966 metadata_stream
->chan
->tracefile_size
,
967 metadata_stream
->tracefile_count_current
,
968 metadata_stream
->uid
, metadata_stream
->gid
, NULL
);
972 metadata_stream
->out_fd
= ret
;
973 metadata_stream
->tracefile_size_current
= 0;
977 health_code_update();
979 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
);
987 * Clean up the stream completly because the next snapshot will use a new
990 consumer_stream_destroy(metadata_stream
, NULL
);
991 cds_list_del(&metadata_stream
->send_node
);
992 metadata_channel
->metadata_stream
= NULL
;
1000 * Take a snapshot of all the stream of a channel.
1002 * Returns 0 on success, < 0 on error
1004 static int snapshot_channel(uint64_t key
, char *path
, uint64_t relayd_id
,
1005 uint64_t nb_packets_per_stream
, struct lttng_consumer_local_data
*ctx
)
1008 unsigned use_relayd
= 0;
1009 unsigned long consumed_pos
, produced_pos
;
1010 struct lttng_consumer_channel
*channel
;
1011 struct lttng_consumer_stream
*stream
;
1018 if (relayd_id
!= (uint64_t) -1ULL) {
1022 channel
= consumer_find_channel(key
);
1024 ERR("UST snapshot channel not found for key %" PRIu64
, key
);
1028 assert(!channel
->monitor
);
1029 DBG("UST consumer snapshot channel %" PRIu64
, key
);
1031 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
1032 /* Are we at a position _before_ the first available packet ? */
1033 bool before_first_packet
= true;
1035 health_code_update();
1037 /* Lock stream because we are about to change its state. */
1038 pthread_mutex_lock(&stream
->lock
);
1039 stream
->net_seq_idx
= relayd_id
;
1042 ret
= consumer_send_relayd_stream(stream
, path
);
1047 ret
= utils_create_stream_file(path
, stream
->name
,
1048 stream
->chan
->tracefile_size
,
1049 stream
->tracefile_count_current
,
1050 stream
->uid
, stream
->gid
, NULL
);
1054 stream
->out_fd
= ret
;
1055 stream
->tracefile_size_current
= 0;
1057 DBG("UST consumer snapshot stream %s/%s (%" PRIu64
")", path
,
1058 stream
->name
, stream
->key
);
1060 if (relayd_id
!= -1ULL) {
1061 ret
= consumer_send_relayd_streams_sent(relayd_id
);
1067 ustctl_flush_buffer(stream
->ustream
, 1);
1069 ret
= lttng_ustconsumer_take_snapshot(stream
);
1071 ERR("Taking UST snapshot");
1075 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
1077 ERR("Produced UST snapshot position");
1081 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
1083 ERR("Consumerd UST snapshot position");
1088 * The original value is sent back if max stream size is larger than
1089 * the possible size of the snapshot. Also, we assume that the session
1090 * daemon should never send a maximum stream size that is lower than
1093 consumed_pos
= consumer_get_consume_start_pos(consumed_pos
,
1094 produced_pos
, nb_packets_per_stream
,
1095 stream
->max_sb_size
);
1097 while (consumed_pos
< produced_pos
) {
1099 unsigned long len
, padded_len
;
1100 int lost_packet
= 0;
1102 health_code_update();
1104 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
1106 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
1108 if (ret
!= -EAGAIN
) {
1109 PERROR("ustctl_get_subbuf snapshot");
1110 goto error_close_stream
;
1112 DBG("UST consumer get subbuf failed. Skipping it.");
1113 consumed_pos
+= stream
->max_sb_size
;
1116 * Start accounting lost packets only when we
1117 * already have extracted packets (to match the
1118 * content of the final snapshot).
1120 if (!before_first_packet
) {
1126 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
1128 ERR("Snapshot ustctl_get_subbuf_size");
1129 goto error_put_subbuf
;
1132 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
1134 ERR("Snapshot ustctl_get_padded_subbuf_size");
1135 goto error_put_subbuf
;
1138 read_len
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, len
,
1139 padded_len
- len
, NULL
);
1141 if (read_len
!= len
) {
1143 goto error_put_subbuf
;
1146 if (read_len
!= padded_len
) {
1148 goto error_put_subbuf
;
1152 ret
= ustctl_put_subbuf(stream
->ustream
);
1154 ERR("Snapshot ustctl_put_subbuf");
1155 goto error_close_stream
;
1157 consumed_pos
+= stream
->max_sb_size
;
1160 * Only account lost packets located between
1161 * succesfully extracted packets (do not account before
1162 * and after since they are not visible in the
1163 * resulting snapshot).
1165 stream
->chan
->lost_packets
+= lost_packet
;
1167 before_first_packet
= false;
1170 /* Simply close the stream so we can use it on the next snapshot. */
1171 consumer_stream_close(stream
);
1172 pthread_mutex_unlock(&stream
->lock
);
1179 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
1180 ERR("Snapshot ustctl_put_subbuf");
1183 consumer_stream_close(stream
);
1185 pthread_mutex_unlock(&stream
->lock
);
1192 * Receive the metadata updates from the sessiond. Supports receiving
1193 * overlapping metadata, but is needs to always belong to a contiguous
1194 * range starting from 0.
1195 * Be careful about the locks held when calling this function: it needs
1196 * the metadata cache flush to concurrently progress in order to
1199 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
1200 uint64_t len
, uint64_t version
,
1201 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
1203 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1206 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
1208 metadata_str
= zmalloc(len
* sizeof(char));
1209 if (!metadata_str
) {
1210 PERROR("zmalloc metadata string");
1211 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
1215 health_code_update();
1217 /* Receive metadata string. */
1218 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1220 /* Session daemon is dead so return gracefully. */
1225 health_code_update();
1227 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1228 ret
= consumer_metadata_cache_write(channel
, offset
, len
, version
,
1231 /* Unable to handle metadata. Notify session daemon. */
1232 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1234 * Skip metadata flush on write error since the offset and len might
1235 * not have been updated which could create an infinite loop below when
1236 * waiting for the metadata cache to be flushed.
1238 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1241 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1246 while (consumer_metadata_cache_flushed(channel
, offset
+ len
, timer
)) {
1247 DBG("Waiting for metadata to be flushed");
1249 health_code_update();
1251 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1261 * Receive command from session daemon and process it.
1263 * Return 1 on success else a negative value or 0.
1265 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1266 int sock
, struct pollfd
*consumer_sockpoll
)
1269 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1270 struct lttcomm_consumer_msg msg
;
1271 struct lttng_consumer_channel
*channel
= NULL
;
1273 health_code_update();
1275 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1276 if (ret
!= sizeof(msg
)) {
1277 DBG("Consumer received unexpected message size %zd (expects %zu)",
1280 * The ret value might 0 meaning an orderly shutdown but this is ok
1281 * since the caller handles this.
1284 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1290 health_code_update();
1293 assert(msg
.cmd_type
!= LTTNG_CONSUMER_STOP
);
1295 health_code_update();
1297 /* relayd needs RCU read-side lock */
1300 switch (msg
.cmd_type
) {
1301 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1303 /* Session daemon status message are handled in the following call. */
1304 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1305 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1306 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
,
1307 msg
.u
.relayd_sock
.relayd_session_id
);
1310 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1312 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1313 struct consumer_relayd_sock_pair
*relayd
;
1315 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1317 /* Get relayd reference if exists. */
1318 relayd
= consumer_find_relayd(index
);
1319 if (relayd
== NULL
) {
1320 DBG("Unable to find relayd %" PRIu64
, index
);
1321 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
1325 * Each relayd socket pair has a refcount of stream attached to it
1326 * which tells if the relayd is still active or not depending on the
1329 * This will set the destroy flag of the relayd object and destroy it
1330 * if the refcount reaches zero when called.
1332 * The destroy can happen either here or when a stream fd hangs up.
1335 consumer_flag_relayd_for_destroy(relayd
);
1338 goto end_msg_sessiond
;
1340 case LTTNG_CONSUMER_UPDATE_STREAM
:
1345 case LTTNG_CONSUMER_DATA_PENDING
:
1347 int ret
, is_data_pending
;
1348 uint64_t id
= msg
.u
.data_pending
.session_id
;
1350 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1352 is_data_pending
= consumer_data_pending(id
);
1354 /* Send back returned value to session daemon */
1355 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1356 sizeof(is_data_pending
));
1358 DBG("Error when sending the data pending ret code: %d", ret
);
1363 * No need to send back a status message since the data pending
1364 * returned value is the response.
1368 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1371 struct ustctl_consumer_channel_attr attr
;
1373 /* Create a plain object and reserve a channel key. */
1374 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
1375 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
1376 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
1377 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
1378 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1379 msg
.u
.ask_channel
.tracefile_size
,
1380 msg
.u
.ask_channel
.tracefile_count
,
1381 msg
.u
.ask_channel
.session_id_per_pid
,
1382 msg
.u
.ask_channel
.monitor
,
1383 msg
.u
.ask_channel
.live_timer_interval
,
1384 msg
.u
.ask_channel
.root_shm_path
,
1385 msg
.u
.ask_channel
.shm_path
);
1387 goto end_channel_error
;
1391 * Assign UST application UID to the channel. This value is ignored for
1392 * per PID buffers. This is specific to UST thus setting this after the
1395 channel
->ust_app_uid
= msg
.u
.ask_channel
.ust_app_uid
;
1397 /* Build channel attributes from received message. */
1398 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1399 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1400 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1401 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1402 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1403 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1404 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1406 /* Match channel buffer type to the UST abi. */
1407 switch (msg
.u
.ask_channel
.output
) {
1408 case LTTNG_EVENT_MMAP
:
1410 attr
.output
= LTTNG_UST_MMAP
;
1414 /* Translate and save channel type. */
1415 switch (msg
.u
.ask_channel
.type
) {
1416 case LTTNG_UST_CHAN_PER_CPU
:
1417 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1418 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1420 * Set refcount to 1 for owner. Below, we will
1421 * pass ownership to the
1422 * consumer_thread_channel_poll() thread.
1424 channel
->refcount
= 1;
1426 case LTTNG_UST_CHAN_METADATA
:
1427 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1428 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1435 health_code_update();
1437 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
1439 goto end_channel_error
;
1442 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1443 ret
= consumer_metadata_cache_allocate(channel
);
1445 ERR("Allocating metadata cache");
1446 goto end_channel_error
;
1448 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1449 attr
.switch_timer_interval
= 0;
1451 consumer_timer_live_start(channel
,
1452 msg
.u
.ask_channel
.live_timer_interval
);
1455 health_code_update();
1458 * Add the channel to the internal state AFTER all streams were created
1459 * and successfully sent to session daemon. This way, all streams must
1460 * be ready before this channel is visible to the threads.
1461 * If add_channel succeeds, ownership of the channel is
1462 * passed to consumer_thread_channel_poll().
1464 ret
= add_channel(channel
, ctx
);
1466 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1467 if (channel
->switch_timer_enabled
== 1) {
1468 consumer_timer_switch_stop(channel
);
1470 consumer_metadata_cache_destroy(channel
);
1472 if (channel
->live_timer_enabled
== 1) {
1473 consumer_timer_live_stop(channel
);
1475 goto end_channel_error
;
1478 health_code_update();
1481 * Channel and streams are now created. Inform the session daemon that
1482 * everything went well and should wait to receive the channel and
1483 * streams with ustctl API.
1485 ret
= consumer_send_status_channel(sock
, channel
);
1488 * There is probably a problem on the socket.
1495 case LTTNG_CONSUMER_GET_CHANNEL
:
1497 int ret
, relayd_err
= 0;
1498 uint64_t key
= msg
.u
.get_channel
.key
;
1499 struct lttng_consumer_channel
*channel
;
1501 channel
= consumer_find_channel(key
);
1503 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1504 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1505 goto end_msg_sessiond
;
1508 health_code_update();
1510 /* Send everything to sessiond. */
1511 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1515 * We were unable to send to the relayd the stream so avoid
1516 * sending back a fatal error to the thread since this is OK
1517 * and the consumer can continue its work. The above call
1518 * has sent the error status message to the sessiond.
1523 * The communicaton was broken hence there is a bad state between
1524 * the consumer and sessiond so stop everything.
1529 health_code_update();
1532 * In no monitor mode, the streams ownership is kept inside the channel
1533 * so don't send them to the data thread.
1535 if (!channel
->monitor
) {
1536 goto end_msg_sessiond
;
1539 ret
= send_streams_to_thread(channel
, ctx
);
1542 * If we are unable to send the stream to the thread, there is
1543 * a big problem so just stop everything.
1547 /* List MUST be empty after or else it could be reused. */
1548 assert(cds_list_empty(&channel
->streams
.head
));
1549 goto end_msg_sessiond
;
1551 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1553 uint64_t key
= msg
.u
.destroy_channel
.key
;
1556 * Only called if streams have not been sent to stream
1557 * manager thread. However, channel has been sent to
1558 * channel manager thread.
1560 notify_thread_del_channel(ctx
, key
);
1561 goto end_msg_sessiond
;
1563 case LTTNG_CONSUMER_CLOSE_METADATA
:
1567 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1572 goto end_msg_sessiond
;
1574 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1578 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1583 goto end_msg_sessiond
;
1585 case LTTNG_CONSUMER_PUSH_METADATA
:
1588 uint64_t len
= msg
.u
.push_metadata
.len
;
1589 uint64_t key
= msg
.u
.push_metadata
.key
;
1590 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1591 uint64_t version
= msg
.u
.push_metadata
.version
;
1592 struct lttng_consumer_channel
*channel
;
1594 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1597 channel
= consumer_find_channel(key
);
1600 * This is possible if the metadata creation on the consumer side
1601 * is in flight vis-a-vis a concurrent push metadata from the
1602 * session daemon. Simply return that the channel failed and the
1603 * session daemon will handle that message correctly considering
1604 * that this race is acceptable thus the DBG() statement here.
1606 DBG("UST consumer push metadata %" PRIu64
" not found", key
);
1607 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1608 goto end_msg_sessiond
;
1611 health_code_update();
1615 * There is nothing to receive. We have simply
1616 * checked whether the channel can be found.
1618 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1619 goto end_msg_sessiond
;
1622 /* Tell session daemon we are ready to receive the metadata. */
1623 ret
= consumer_send_status_msg(sock
, LTTCOMM_CONSUMERD_SUCCESS
);
1625 /* Somehow, the session daemon is not responding anymore. */
1629 health_code_update();
1631 /* Wait for more data. */
1632 health_poll_entry();
1633 ret
= lttng_consumer_poll_socket(consumer_sockpoll
);
1639 health_code_update();
1641 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1642 len
, version
, channel
, 0, 1);
1644 /* error receiving from sessiond */
1648 goto end_msg_sessiond
;
1651 case LTTNG_CONSUMER_SETUP_METADATA
:
1655 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1659 goto end_msg_sessiond
;
1661 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1663 if (msg
.u
.snapshot_channel
.metadata
) {
1664 ret
= snapshot_metadata(msg
.u
.snapshot_channel
.key
,
1665 msg
.u
.snapshot_channel
.pathname
,
1666 msg
.u
.snapshot_channel
.relayd_id
,
1669 ERR("Snapshot metadata failed");
1670 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1673 ret
= snapshot_channel(msg
.u
.snapshot_channel
.key
,
1674 msg
.u
.snapshot_channel
.pathname
,
1675 msg
.u
.snapshot_channel
.relayd_id
,
1676 msg
.u
.snapshot_channel
.nb_packets_per_stream
,
1679 ERR("Snapshot channel failed");
1680 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1684 health_code_update();
1685 ret
= consumer_send_status_msg(sock
, ret_code
);
1687 /* Somehow, the session daemon is not responding anymore. */
1690 health_code_update();
1693 case LTTNG_CONSUMER_DISCARDED_EVENTS
:
1696 uint64_t discarded_events
;
1697 struct lttng_ht_iter iter
;
1698 struct lttng_ht
*ht
;
1699 struct lttng_consumer_stream
*stream
;
1700 uint64_t id
= msg
.u
.discarded_events
.session_id
;
1701 uint64_t key
= msg
.u
.discarded_events
.channel_key
;
1703 DBG("UST consumer discarded events command for session id %"
1706 pthread_mutex_lock(&consumer_data
.lock
);
1708 ht
= consumer_data
.stream_list_ht
;
1711 * We only need a reference to the channel, but they are not
1712 * directly indexed, so we just use the first matching stream
1713 * to extract the information we need, we default to 0 if not
1714 * found (no events are dropped if the channel is not yet in
1717 discarded_events
= 0;
1718 cds_lfht_for_each_entry_duplicate(ht
->ht
,
1719 ht
->hash_fct(&id
, lttng_ht_seed
),
1721 &iter
.iter
, stream
, node_session_id
.node
) {
1722 if (stream
->chan
->key
== key
) {
1723 discarded_events
= stream
->chan
->discarded_events
;
1727 pthread_mutex_unlock(&consumer_data
.lock
);
1730 DBG("UST consumer discarded events command for session id %"
1731 PRIu64
", channel key %" PRIu64
, id
, key
);
1733 health_code_update();
1735 /* Send back returned value to session daemon */
1736 ret
= lttcomm_send_unix_sock(sock
, &discarded_events
, sizeof(discarded_events
));
1738 PERROR("send discarded events");
1744 case LTTNG_CONSUMER_LOST_PACKETS
:
1747 uint64_t lost_packets
;
1748 struct lttng_ht_iter iter
;
1749 struct lttng_ht
*ht
;
1750 struct lttng_consumer_stream
*stream
;
1751 uint64_t id
= msg
.u
.lost_packets
.session_id
;
1752 uint64_t key
= msg
.u
.lost_packets
.channel_key
;
1754 DBG("UST consumer lost packets command for session id %"
1757 pthread_mutex_lock(&consumer_data
.lock
);
1759 ht
= consumer_data
.stream_list_ht
;
1762 * We only need a reference to the channel, but they are not
1763 * directly indexed, so we just use the first matching stream
1764 * to extract the information we need, we default to 0 if not
1765 * found (no packets lost if the channel is not yet in use).
1768 cds_lfht_for_each_entry_duplicate(ht
->ht
,
1769 ht
->hash_fct(&id
, lttng_ht_seed
),
1771 &iter
.iter
, stream
, node_session_id
.node
) {
1772 if (stream
->chan
->key
== key
) {
1773 lost_packets
= stream
->chan
->lost_packets
;
1777 pthread_mutex_unlock(&consumer_data
.lock
);
1780 DBG("UST consumer lost packets command for session id %"
1781 PRIu64
", channel key %" PRIu64
, id
, key
);
1783 health_code_update();
1785 /* Send back returned value to session daemon */
1786 ret
= lttcomm_send_unix_sock(sock
, &lost_packets
,
1787 sizeof(lost_packets
));
1789 PERROR("send lost packets");
1802 health_code_update();
1805 * Return 1 to indicate success since the 0 value can be a socket
1806 * shutdown during the recv() or send() call.
1812 * The returned value here is not useful since either way we'll return 1 to
1813 * the caller because the session daemon socket management is done
1814 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1816 ret
= consumer_send_status_msg(sock
, ret_code
);
1822 health_code_update();
1828 * Free channel here since no one has a reference to it. We don't
1829 * free after that because a stream can store this pointer.
1831 destroy_channel(channel
);
1833 /* We have to send a status channel message indicating an error. */
1834 ret
= consumer_send_status_channel(sock
, NULL
);
1836 /* Stop everything if session daemon can not be notified. */
1841 health_code_update();
1846 /* This will issue a consumer stop. */
1851 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1852 * compiled out, we isolate it in this library.
1854 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1858 assert(stream
->ustream
);
1860 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1864 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1865 * compiled out, we isolate it in this library.
1867 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1870 assert(stream
->ustream
);
1872 return ustctl_get_mmap_base(stream
->ustream
);
1876 * Take a snapshot for a specific fd
1878 * Returns 0 on success, < 0 on error
1880 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1883 assert(stream
->ustream
);
1885 return ustctl_snapshot(stream
->ustream
);
1889 * Get the produced position
1891 * Returns 0 on success, < 0 on error
1893 int lttng_ustconsumer_get_produced_snapshot(
1894 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1897 assert(stream
->ustream
);
1900 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1904 * Get the consumed position
1906 * Returns 0 on success, < 0 on error
1908 int lttng_ustconsumer_get_consumed_snapshot(
1909 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1912 assert(stream
->ustream
);
1915 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
1918 void lttng_ustconsumer_flush_buffer(struct lttng_consumer_stream
*stream
,
1922 assert(stream
->ustream
);
1924 ustctl_flush_buffer(stream
->ustream
, producer
);
1927 int lttng_ustconsumer_get_current_timestamp(
1928 struct lttng_consumer_stream
*stream
, uint64_t *ts
)
1931 assert(stream
->ustream
);
1934 return ustctl_get_current_timestamp(stream
->ustream
, ts
);
1937 int lttng_ustconsumer_get_sequence_number(
1938 struct lttng_consumer_stream
*stream
, uint64_t *seq
)
1941 assert(stream
->ustream
);
1944 return ustctl_get_sequence_number(stream
->ustream
, seq
);
1948 * Called when the stream signal the consumer that it has hang up.
1950 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1953 assert(stream
->ustream
);
1955 ustctl_flush_buffer(stream
->ustream
, 0);
1956 stream
->hangup_flush_done
= 1;
1959 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1964 assert(chan
->uchan
);
1966 if (chan
->switch_timer_enabled
== 1) {
1967 consumer_timer_switch_stop(chan
);
1969 for (i
= 0; i
< chan
->nr_stream_fds
; i
++) {
1972 ret
= close(chan
->stream_fds
[i
]);
1976 if (chan
->shm_path
[0]) {
1977 char shm_path
[PATH_MAX
];
1979 ret
= get_stream_shm_path(shm_path
, chan
->shm_path
, i
);
1981 ERR("Cannot get stream shm path");
1983 ret
= run_as_unlink(shm_path
, chan
->uid
, chan
->gid
);
1985 PERROR("unlink %s", shm_path
);
1991 void lttng_ustconsumer_free_channel(struct lttng_consumer_channel
*chan
)
1994 assert(chan
->uchan
);
1996 consumer_metadata_cache_destroy(chan
);
1997 ustctl_destroy_channel(chan
->uchan
);
1998 /* Try to rmdir all directories under shm_path root. */
1999 if (chan
->root_shm_path
[0]) {
2000 (void) run_as_recursive_rmdir(chan
->root_shm_path
,
2001 chan
->uid
, chan
->gid
);
2003 free(chan
->stream_fds
);
2006 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
2009 assert(stream
->ustream
);
2011 if (stream
->chan
->switch_timer_enabled
== 1) {
2012 consumer_timer_switch_stop(stream
->chan
);
2014 ustctl_destroy_stream(stream
->ustream
);
2017 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream
*stream
)
2020 assert(stream
->ustream
);
2022 return ustctl_stream_get_wakeup_fd(stream
->ustream
);
2025 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream
*stream
)
2028 assert(stream
->ustream
);
2030 return ustctl_stream_close_wakeup_fd(stream
->ustream
);
2034 * Populate index values of a UST stream. Values are set in big endian order.
2036 * Return 0 on success or else a negative value.
2038 static int get_index_values(struct ctf_packet_index
*index
,
2039 struct ustctl_consumer_stream
*ustream
)
2043 ret
= ustctl_get_timestamp_begin(ustream
, &index
->timestamp_begin
);
2045 PERROR("ustctl_get_timestamp_begin");
2048 index
->timestamp_begin
= htobe64(index
->timestamp_begin
);
2050 ret
= ustctl_get_timestamp_end(ustream
, &index
->timestamp_end
);
2052 PERROR("ustctl_get_timestamp_end");
2055 index
->timestamp_end
= htobe64(index
->timestamp_end
);
2057 ret
= ustctl_get_events_discarded(ustream
, &index
->events_discarded
);
2059 PERROR("ustctl_get_events_discarded");
2062 index
->events_discarded
= htobe64(index
->events_discarded
);
2064 ret
= ustctl_get_content_size(ustream
, &index
->content_size
);
2066 PERROR("ustctl_get_content_size");
2069 index
->content_size
= htobe64(index
->content_size
);
2071 ret
= ustctl_get_packet_size(ustream
, &index
->packet_size
);
2073 PERROR("ustctl_get_packet_size");
2076 index
->packet_size
= htobe64(index
->packet_size
);
2078 ret
= ustctl_get_stream_id(ustream
, &index
->stream_id
);
2080 PERROR("ustctl_get_stream_id");
2083 index
->stream_id
= htobe64(index
->stream_id
);
2085 ret
= ustctl_get_instance_id(ustream
, &index
->stream_instance_id
);
2087 PERROR("ustctl_get_instance_id");
2090 index
->stream_instance_id
= htobe64(index
->stream_instance_id
);
2092 ret
= ustctl_get_sequence_number(ustream
, &index
->packet_seq_num
);
2094 PERROR("ustctl_get_sequence_number");
2097 index
->packet_seq_num
= htobe64(index
->packet_seq_num
);
2104 void metadata_stream_reset_cache(struct lttng_consumer_stream
*stream
,
2105 struct consumer_metadata_cache
*cache
)
2107 DBG("Metadata stream update to version %" PRIu64
,
2109 stream
->ust_metadata_pushed
= 0;
2110 stream
->metadata_version
= cache
->version
;
2111 stream
->reset_metadata_flag
= 1;
2115 * Check if the version of the metadata stream and metadata cache match.
2116 * If the cache got updated, reset the metadata stream.
2117 * The stream lock and metadata cache lock MUST be held.
2118 * Return 0 on success, a negative value on error.
2121 int metadata_stream_check_version(struct lttng_consumer_stream
*stream
)
2124 struct consumer_metadata_cache
*cache
= stream
->chan
->metadata_cache
;
2126 if (cache
->version
== stream
->metadata_version
) {
2129 metadata_stream_reset_cache(stream
, cache
);
2136 * Write up to one packet from the metadata cache to the channel.
2138 * Returns the number of bytes pushed in the cache, or a negative value
2142 int commit_one_metadata_packet(struct lttng_consumer_stream
*stream
)
2147 pthread_mutex_lock(&stream
->chan
->metadata_cache
->lock
);
2148 ret
= metadata_stream_check_version(stream
);
2152 if (stream
->chan
->metadata_cache
->max_offset
2153 == stream
->ust_metadata_pushed
) {
2158 write_len
= ustctl_write_one_packet_to_channel(stream
->chan
->uchan
,
2159 &stream
->chan
->metadata_cache
->data
[stream
->ust_metadata_pushed
],
2160 stream
->chan
->metadata_cache
->max_offset
2161 - stream
->ust_metadata_pushed
);
2162 assert(write_len
!= 0);
2163 if (write_len
< 0) {
2164 ERR("Writing one metadata packet");
2168 stream
->ust_metadata_pushed
+= write_len
;
2170 assert(stream
->chan
->metadata_cache
->max_offset
>=
2171 stream
->ust_metadata_pushed
);
2175 pthread_mutex_unlock(&stream
->chan
->metadata_cache
->lock
);
2181 * Sync metadata meaning request them to the session daemon and snapshot to the
2182 * metadata thread can consumer them.
2184 * Metadata stream lock is held here, but we need to release it when
2185 * interacting with sessiond, else we cause a deadlock with live
2186 * awaiting on metadata to be pushed out.
2188 * Return 0 if new metadatda is available, EAGAIN if the metadata stream
2189 * is empty or a negative value on error.
2191 int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data
*ctx
,
2192 struct lttng_consumer_stream
*metadata
)
2200 pthread_mutex_unlock(&metadata
->lock
);
2202 * Request metadata from the sessiond, but don't wait for the flush
2203 * because we locked the metadata thread.
2205 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata
->chan
, 0, 0);
2209 pthread_mutex_lock(&metadata
->lock
);
2211 ret
= commit_one_metadata_packet(metadata
);
2214 } else if (ret
> 0) {
2218 ustctl_flush_buffer(metadata
->ustream
, 1);
2219 ret
= ustctl_snapshot(metadata
->ustream
);
2221 if (errno
!= EAGAIN
) {
2222 ERR("Sync metadata, taking UST snapshot");
2225 DBG("No new metadata when syncing them.");
2226 /* No new metadata, exit. */
2232 * After this flush, we still need to extract metadata.
2243 * Return 0 on success else a negative value.
2245 static int notify_if_more_data(struct lttng_consumer_stream
*stream
,
2246 struct lttng_consumer_local_data
*ctx
)
2249 struct ustctl_consumer_stream
*ustream
;
2254 ustream
= stream
->ustream
;
2257 * First, we are going to check if there is a new subbuffer available
2258 * before reading the stream wait_fd.
2260 /* Get the next subbuffer */
2261 ret
= ustctl_get_next_subbuf(ustream
);
2263 /* No more data found, flag the stream. */
2264 stream
->has_data
= 0;
2269 ret
= ustctl_put_subbuf(ustream
);
2272 /* This stream still has data. Flag it and wake up the data thread. */
2273 stream
->has_data
= 1;
2275 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !ctx
->has_wakeup
) {
2278 writelen
= lttng_pipe_write(ctx
->consumer_wakeup_pipe
, "!", 1);
2279 if (writelen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2284 /* The wake up pipe has been notified. */
2285 ctx
->has_wakeup
= 1;
2294 int update_stream_stats(struct lttng_consumer_stream
*stream
)
2297 uint64_t seq
, discarded
;
2299 ret
= ustctl_get_sequence_number(stream
->ustream
, &seq
);
2301 PERROR("ustctl_get_sequence_number");
2305 * Start the sequence when we extract the first packet in case we don't
2306 * start at 0 (for example if a consumer is not connected to the
2307 * session immediately after the beginning).
2309 if (stream
->last_sequence_number
== -1ULL) {
2310 stream
->last_sequence_number
= seq
;
2311 } else if (seq
> stream
->last_sequence_number
) {
2312 stream
->chan
->lost_packets
+= seq
-
2313 stream
->last_sequence_number
- 1;
2315 /* seq <= last_sequence_number */
2316 ERR("Sequence number inconsistent : prev = %" PRIu64
2317 ", current = %" PRIu64
,
2318 stream
->last_sequence_number
, seq
);
2322 stream
->last_sequence_number
= seq
;
2324 ret
= ustctl_get_events_discarded(stream
->ustream
, &discarded
);
2326 PERROR("kernctl_get_events_discarded");
2329 if (discarded
< stream
->last_discarded_events
) {
2331 * Overflow has occured. We assume only one wrap-around
2334 stream
->chan
->discarded_events
+=
2335 (1ULL << (CAA_BITS_PER_LONG
- 1)) -
2336 stream
->last_discarded_events
+ discarded
;
2338 stream
->chan
->discarded_events
+= discarded
-
2339 stream
->last_discarded_events
;
2341 stream
->last_discarded_events
= discarded
;
2349 * Read subbuffer from the given stream.
2351 * Stream lock MUST be acquired.
2353 * Return 0 on success else a negative value.
2355 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
2356 struct lttng_consumer_local_data
*ctx
)
2358 unsigned long len
, subbuf_size
, padding
;
2359 int err
, write_index
= 1;
2361 struct ustctl_consumer_stream
*ustream
;
2362 struct ctf_packet_index index
;
2365 assert(stream
->ustream
);
2368 DBG("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
2371 /* Ease our life for what's next. */
2372 ustream
= stream
->ustream
;
2375 * We can consume the 1 byte written into the wait_fd by UST. Don't trigger
2376 * error if we cannot read this one byte (read returns 0), or if the error
2377 * is EAGAIN or EWOULDBLOCK.
2379 * This is only done when the stream is monitored by a thread, before the
2380 * flush is done after a hangup and if the stream is not flagged with data
2381 * since there might be nothing to consume in the wait fd but still have
2382 * data available flagged by the consumer wake up pipe.
2384 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !stream
->has_data
) {
2388 readlen
= lttng_read(stream
->wait_fd
, &dummy
, 1);
2389 if (readlen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2396 /* Get the next subbuffer */
2397 err
= ustctl_get_next_subbuf(ustream
);
2400 * Populate metadata info if the existing info has
2401 * already been read.
2403 if (stream
->metadata_flag
) {
2404 ret
= commit_one_metadata_packet(stream
);
2408 ustctl_flush_buffer(stream
->ustream
, 1);
2412 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
2414 * This is a debug message even for single-threaded consumer,
2415 * because poll() have more relaxed criterions than get subbuf,
2416 * so get_subbuf may fail for short race windows where poll()
2417 * would issue wakeups.
2419 DBG("Reserving sub buffer failed (everything is normal, "
2420 "it is due to concurrency) [ret: %d]", err
);
2423 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
2425 if (!stream
->metadata_flag
) {
2426 index
.offset
= htobe64(stream
->out_fd_offset
);
2427 ret
= get_index_values(&index
, ustream
);
2432 /* Update the stream's sequence and discarded events count. */
2433 ret
= update_stream_stats(stream
);
2435 PERROR("kernctl_get_events_discarded");
2442 /* Get the full padded subbuffer size */
2443 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
2446 /* Get subbuffer data size (without padding) */
2447 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
2450 /* Make sure we don't get a subbuffer size bigger than the padded */
2451 assert(len
>= subbuf_size
);
2453 padding
= len
- subbuf_size
;
2454 /* write the subbuffer to the tracefile */
2455 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
, &index
);
2457 * The mmap operation should write subbuf_size amount of data when network
2458 * streaming or the full padding (len) size when we are _not_ streaming.
2460 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
2461 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
2463 * Display the error but continue processing to try to release the
2464 * subbuffer. This is a DBG statement since any unexpected kill or
2465 * signal, the application gets unregistered, relayd gets closed or
2466 * anything that affects the buffer lifetime will trigger this error.
2467 * So, for the sake of the user, don't print this error since it can
2468 * happen and it is OK with the code flow.
2470 DBG("Error writing to tracefile "
2471 "(ret: %ld != len: %lu != subbuf_size: %lu)",
2472 ret
, len
, subbuf_size
);
2475 err
= ustctl_put_next_subbuf(ustream
);
2479 * This will consumer the byte on the wait_fd if and only if there is not
2480 * next subbuffer to be acquired.
2482 if (!stream
->metadata_flag
) {
2483 ret
= notify_if_more_data(stream
, ctx
);
2489 /* Write index if needed. */
2494 if (stream
->chan
->live_timer_interval
&& !stream
->metadata_flag
) {
2496 * In live, block until all the metadata is sent.
2498 pthread_mutex_lock(&stream
->metadata_timer_lock
);
2499 assert(!stream
->missed_metadata_flush
);
2500 stream
->waiting_on_metadata
= true;
2501 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2503 err
= consumer_stream_sync_metadata(ctx
, stream
->session_id
);
2505 pthread_mutex_lock(&stream
->metadata_timer_lock
);
2506 stream
->waiting_on_metadata
= false;
2507 if (stream
->missed_metadata_flush
) {
2508 stream
->missed_metadata_flush
= false;
2509 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2510 (void) consumer_flush_ust_index(stream
);
2512 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2520 assert(!stream
->metadata_flag
);
2521 err
= consumer_stream_write_index(stream
, &index
);
2531 * Called when a stream is created.
2533 * Return 0 on success or else a negative value.
2535 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
2541 /* Don't create anything if this is set for streaming. */
2542 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
) {
2543 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
2544 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
2545 stream
->uid
, stream
->gid
, NULL
);
2549 stream
->out_fd
= ret
;
2550 stream
->tracefile_size_current
= 0;
2552 if (!stream
->metadata_flag
) {
2553 ret
= index_create_file(stream
->chan
->pathname
,
2554 stream
->name
, stream
->uid
, stream
->gid
,
2555 stream
->chan
->tracefile_size
,
2556 stream
->tracefile_count_current
);
2560 stream
->index_fd
= ret
;
2570 * Check if data is still being extracted from the buffers for a specific
2571 * stream. Consumer data lock MUST be acquired before calling this function
2572 * and the stream lock.
2574 * Return 1 if the traced data are still getting read else 0 meaning that the
2575 * data is available for trace viewer reading.
2577 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
2582 assert(stream
->ustream
);
2584 DBG("UST consumer checking data pending");
2586 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
2591 if (stream
->chan
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
2592 uint64_t contiguous
, pushed
;
2594 /* Ease our life a bit. */
2595 contiguous
= stream
->chan
->metadata_cache
->max_offset
;
2596 pushed
= stream
->ust_metadata_pushed
;
2599 * We can simply check whether all contiguously available data
2600 * has been pushed to the ring buffer, since the push operation
2601 * is performed within get_next_subbuf(), and because both
2602 * get_next_subbuf() and put_next_subbuf() are issued atomically
2603 * thanks to the stream lock within
2604 * lttng_ustconsumer_read_subbuffer(). This basically means that
2605 * whetnever ust_metadata_pushed is incremented, the associated
2606 * metadata has been consumed from the metadata stream.
2608 DBG("UST consumer metadata pending check: contiguous %" PRIu64
" vs pushed %" PRIu64
,
2609 contiguous
, pushed
);
2610 assert(((int64_t) (contiguous
- pushed
)) >= 0);
2611 if ((contiguous
!= pushed
) ||
2612 (((int64_t) contiguous
- pushed
) > 0 || contiguous
== 0)) {
2613 ret
= 1; /* Data is pending */
2617 ret
= ustctl_get_next_subbuf(stream
->ustream
);
2620 * There is still data so let's put back this
2623 ret
= ustctl_put_subbuf(stream
->ustream
);
2625 ret
= 1; /* Data is pending */
2630 /* Data is NOT pending so ready to be read. */
2638 * Stop a given metadata channel timer if enabled and close the wait fd which
2639 * is the poll pipe of the metadata stream.
2641 * This MUST be called with the metadata channel acquired.
2643 void lttng_ustconsumer_close_metadata(struct lttng_consumer_channel
*metadata
)
2648 assert(metadata
->type
== CONSUMER_CHANNEL_TYPE_METADATA
);
2650 DBG("Closing metadata channel key %" PRIu64
, metadata
->key
);
2652 if (metadata
->switch_timer_enabled
== 1) {
2653 consumer_timer_switch_stop(metadata
);
2656 if (!metadata
->metadata_stream
) {
2661 * Closing write side so the thread monitoring the stream wakes up if any
2662 * and clean the metadata stream.
2664 if (metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] >= 0) {
2665 ret
= close(metadata
->metadata_stream
->ust_metadata_poll_pipe
[1]);
2667 PERROR("closing metadata pipe write side");
2669 metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] = -1;
2677 * Close every metadata stream wait fd of the metadata hash table. This
2678 * function MUST be used very carefully so not to run into a race between the
2679 * metadata thread handling streams and this function closing their wait fd.
2681 * For UST, this is used when the session daemon hangs up. Its the metadata
2682 * producer so calling this is safe because we are assured that no state change
2683 * can occur in the metadata thread for the streams in the hash table.
2685 void lttng_ustconsumer_close_all_metadata(struct lttng_ht
*metadata_ht
)
2687 struct lttng_ht_iter iter
;
2688 struct lttng_consumer_stream
*stream
;
2690 assert(metadata_ht
);
2691 assert(metadata_ht
->ht
);
2693 DBG("UST consumer closing all metadata streams");
2696 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
2699 health_code_update();
2701 pthread_mutex_lock(&stream
->chan
->lock
);
2702 lttng_ustconsumer_close_metadata(stream
->chan
);
2703 pthread_mutex_unlock(&stream
->chan
->lock
);
2709 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
2713 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
2715 ERR("Unable to close wakeup fd");
2720 * Please refer to consumer-timer.c before adding any lock within this
2721 * function or any of its callees. Timers have a very strict locking
2722 * semantic with respect to teardown. Failure to respect this semantic
2723 * introduces deadlocks.
2725 * DON'T hold the metadata lock when calling this function, else this
2726 * can cause deadlock involving consumer awaiting for metadata to be
2727 * pushed out due to concurrent interaction with the session daemon.
2729 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
2730 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
2732 struct lttcomm_metadata_request_msg request
;
2733 struct lttcomm_consumer_msg msg
;
2734 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
2735 uint64_t len
, key
, offset
, version
;
2739 assert(channel
->metadata_cache
);
2741 memset(&request
, 0, sizeof(request
));
2743 /* send the metadata request to sessiond */
2744 switch (consumer_data
.type
) {
2745 case LTTNG_CONSUMER64_UST
:
2746 request
.bits_per_long
= 64;
2748 case LTTNG_CONSUMER32_UST
:
2749 request
.bits_per_long
= 32;
2752 request
.bits_per_long
= 0;
2756 request
.session_id
= channel
->session_id
;
2757 request
.session_id_per_pid
= channel
->session_id_per_pid
;
2759 * Request the application UID here so the metadata of that application can
2760 * be sent back. The channel UID corresponds to the user UID of the session
2761 * used for the rights on the stream file(s).
2763 request
.uid
= channel
->ust_app_uid
;
2764 request
.key
= channel
->key
;
2766 DBG("Sending metadata request to sessiond, session id %" PRIu64
2767 ", per-pid %" PRIu64
", app UID %u and channek key %" PRIu64
,
2768 request
.session_id
, request
.session_id_per_pid
, request
.uid
,
2771 pthread_mutex_lock(&ctx
->metadata_socket_lock
);
2773 health_code_update();
2775 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
2778 ERR("Asking metadata to sessiond");
2782 health_code_update();
2784 /* Receive the metadata from sessiond */
2785 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
2787 if (ret
!= sizeof(msg
)) {
2788 DBG("Consumer received unexpected message size %d (expects %zu)",
2790 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
2792 * The ret value might 0 meaning an orderly shutdown but this is ok
2793 * since the caller handles this.
2798 health_code_update();
2800 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
2801 /* No registry found */
2802 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2806 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
2807 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
2812 len
= msg
.u
.push_metadata
.len
;
2813 key
= msg
.u
.push_metadata
.key
;
2814 offset
= msg
.u
.push_metadata
.target_offset
;
2815 version
= msg
.u
.push_metadata
.version
;
2817 assert(key
== channel
->key
);
2819 DBG("No new metadata to receive for key %" PRIu64
, key
);
2822 health_code_update();
2824 /* Tell session daemon we are ready to receive the metadata. */
2825 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2826 LTTCOMM_CONSUMERD_SUCCESS
);
2827 if (ret
< 0 || len
== 0) {
2829 * Somehow, the session daemon is not responding anymore or there is
2830 * nothing to receive.
2835 health_code_update();
2837 ret
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
2838 key
, offset
, len
, version
, channel
, timer
, wait
);
2841 * Only send the status msg if the sessiond is alive meaning a positive
2844 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret
);
2849 health_code_update();
2851 pthread_mutex_unlock(&ctx
->metadata_socket_lock
);
2856 * Return the ustctl call for the get stream id.
2858 int lttng_ustconsumer_get_stream_id(struct lttng_consumer_stream
*stream
,
2859 uint64_t *stream_id
)
2864 return ustctl_get_stream_id(stream
->ustream
, stream_id
);