2 * Copyright (C) 2011 Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Copyright (C) 2011 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
4 * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
6 * SPDX-License-Identifier: GPL-2.0-only
12 #include <lttng/ust-ctl.h>
18 #include <sys/socket.h>
20 #include <sys/types.h>
23 #include <urcu/list.h>
28 #include <bin/lttng-consumerd/health-consumerd.h>
29 #include <common/common.h>
30 #include <common/sessiond-comm/sessiond-comm.h>
31 #include <common/relayd/relayd.h>
32 #include <common/compat/fcntl.h>
33 #include <common/compat/endian.h>
34 #include <common/consumer/consumer-metadata-cache.h>
35 #include <common/consumer/consumer-stream.h>
36 #include <common/consumer/consumer-timer.h>
37 #include <common/utils.h>
38 #include <common/index/index.h>
39 #include <common/consumer/consumer.h>
40 #include <common/optional.h>
42 #include "ust-consumer.h"
44 #define INT_MAX_STR_LEN 12 /* includes \0 */
46 extern struct lttng_consumer_global_data consumer_data
;
47 extern int consumer_poll_timeout
;
50 * Free channel object and all streams associated with it. This MUST be used
51 * only and only if the channel has _NEVER_ been added to the global channel
54 static void destroy_channel(struct lttng_consumer_channel
*channel
)
56 struct lttng_consumer_stream
*stream
, *stmp
;
60 DBG("UST consumer cleaning stream list");
62 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
67 cds_list_del(&stream
->send_node
);
68 ustctl_destroy_stream(stream
->ustream
);
69 lttng_trace_chunk_put(stream
->trace_chunk
);
74 * If a channel is available meaning that was created before the streams
78 lttng_ustconsumer_del_channel(channel
);
79 lttng_ustconsumer_free_channel(channel
);
82 if (channel
->trace_chunk
) {
83 lttng_trace_chunk_put(channel
->trace_chunk
);
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 stream object. If _alloc_ret is not NULL, the
123 * error value if applicable is set in it else it is kept untouched.
125 * Return NULL on error else the newly allocated stream object.
127 static struct lttng_consumer_stream
*allocate_stream(int cpu
, int key
,
128 struct lttng_consumer_channel
*channel
,
129 struct lttng_consumer_local_data
*ctx
, int *_alloc_ret
)
132 struct lttng_consumer_stream
*stream
= NULL
;
137 stream
= consumer_stream_create(
144 channel
->trace_chunk
,
149 if (stream
== NULL
) {
153 * We could not find the channel. Can happen if cpu hotplug
154 * happens while tearing down.
156 DBG3("Could not find channel");
161 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
167 consumer_stream_update_channel_attributes(stream
, channel
);
171 *_alloc_ret
= alloc_ret
;
177 * Send the given stream pointer to the corresponding thread.
179 * Returns 0 on success else a negative value.
181 static int send_stream_to_thread(struct lttng_consumer_stream
*stream
,
182 struct lttng_consumer_local_data
*ctx
)
185 struct lttng_pipe
*stream_pipe
;
187 /* Get the right pipe where the stream will be sent. */
188 if (stream
->metadata_flag
) {
189 consumer_add_metadata_stream(stream
);
190 stream_pipe
= ctx
->consumer_metadata_pipe
;
192 consumer_add_data_stream(stream
);
193 stream_pipe
= ctx
->consumer_data_pipe
;
197 * From this point on, the stream's ownership has been moved away from
198 * the channel and it becomes globally visible. Hence, remove it from
199 * the local stream list to prevent the stream from being both local and
202 stream
->globally_visible
= 1;
203 cds_list_del(&stream
->send_node
);
205 ret
= lttng_pipe_write(stream_pipe
, &stream
, sizeof(stream
));
207 ERR("Consumer write %s stream to pipe %d",
208 stream
->metadata_flag
? "metadata" : "data",
209 lttng_pipe_get_writefd(stream_pipe
));
210 if (stream
->metadata_flag
) {
211 consumer_del_stream_for_metadata(stream
);
213 consumer_del_stream_for_data(stream
);
223 int get_stream_shm_path(char *stream_shm_path
, const char *shm_path
, int cpu
)
225 char cpu_nr
[INT_MAX_STR_LEN
]; /* int max len */
228 strncpy(stream_shm_path
, shm_path
, PATH_MAX
);
229 stream_shm_path
[PATH_MAX
- 1] = '\0';
230 ret
= snprintf(cpu_nr
, INT_MAX_STR_LEN
, "%i", cpu
);
235 strncat(stream_shm_path
, cpu_nr
,
236 PATH_MAX
- strlen(stream_shm_path
) - 1);
243 * Create streams for the given channel using liblttng-ust-ctl.
244 * The channel lock must be acquired by the caller.
246 * Return 0 on success else a negative value.
248 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
249 struct lttng_consumer_local_data
*ctx
)
252 struct ustctl_consumer_stream
*ustream
;
253 struct lttng_consumer_stream
*stream
;
254 pthread_mutex_t
*current_stream_lock
= NULL
;
260 * While a stream is available from ustctl. When NULL is returned, we've
261 * reached the end of the possible stream for the channel.
263 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
265 int ust_metadata_pipe
[2];
267 health_code_update();
269 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& channel
->monitor
) {
270 ret
= utils_create_pipe_cloexec_nonblock(ust_metadata_pipe
);
272 ERR("Create ust metadata poll pipe");
275 wait_fd
= ust_metadata_pipe
[0];
277 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
280 /* Allocate consumer stream object. */
281 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
285 stream
->ustream
= ustream
;
287 * Store it so we can save multiple function calls afterwards since
288 * this value is used heavily in the stream threads. This is UST
289 * specific so this is why it's done after allocation.
291 stream
->wait_fd
= wait_fd
;
294 * Increment channel refcount since the channel reference has now been
295 * assigned in the allocation process above.
297 if (stream
->chan
->monitor
) {
298 uatomic_inc(&stream
->chan
->refcount
);
301 pthread_mutex_lock(&stream
->lock
);
302 current_stream_lock
= &stream
->lock
;
304 * Order is important this is why a list is used. On error, the caller
305 * should clean this list.
307 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
309 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
310 &stream
->max_sb_size
);
312 ERR("ustctl_get_max_subbuf_size failed for stream %s",
317 /* Do actions once stream has been received. */
318 if (ctx
->on_recv_stream
) {
319 ret
= ctx
->on_recv_stream(stream
);
325 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
326 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
328 /* Set next CPU stream. */
329 channel
->streams
.count
= ++cpu
;
331 /* Keep stream reference when creating metadata. */
332 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
333 channel
->metadata_stream
= stream
;
334 if (channel
->monitor
) {
335 /* Set metadata poll pipe if we created one */
336 memcpy(stream
->ust_metadata_poll_pipe
,
338 sizeof(ust_metadata_pipe
));
341 pthread_mutex_unlock(&stream
->lock
);
342 current_stream_lock
= NULL
;
349 if (current_stream_lock
) {
350 pthread_mutex_unlock(current_stream_lock
);
356 * create_posix_shm is never called concurrently within a process.
359 int create_posix_shm(void)
361 char tmp_name
[NAME_MAX
];
364 ret
= snprintf(tmp_name
, NAME_MAX
, "/ust-shm-consumer-%d", getpid());
370 * Allocate shm, and immediately unlink its shm oject, keeping
371 * only the file descriptor as a reference to the object.
372 * We specifically do _not_ use the / at the beginning of the
373 * pathname so that some OS implementations can keep it local to
374 * the process (POSIX leaves this implementation-defined).
376 shmfd
= shm_open(tmp_name
, O_CREAT
| O_EXCL
| O_RDWR
, 0700);
381 ret
= shm_unlink(tmp_name
);
382 if (ret
< 0 && errno
!= ENOENT
) {
383 PERROR("shm_unlink");
384 goto error_shm_release
;
397 static int open_ust_stream_fd(struct lttng_consumer_channel
*channel
, int cpu
,
398 const struct lttng_credentials
*session_credentials
)
400 char shm_path
[PATH_MAX
];
403 if (!channel
->shm_path
[0]) {
404 return create_posix_shm();
406 ret
= get_stream_shm_path(shm_path
, channel
->shm_path
, cpu
);
410 return run_as_open(shm_path
,
411 O_RDWR
| O_CREAT
| O_EXCL
, S_IRUSR
| S_IWUSR
,
412 session_credentials
->uid
, session_credentials
->gid
);
419 * Create an UST channel with the given attributes and send it to the session
420 * daemon using the ust ctl API.
422 * Return 0 on success or else a negative value.
424 static int create_ust_channel(struct lttng_consumer_channel
*channel
,
425 struct ustctl_consumer_channel_attr
*attr
,
426 struct ustctl_consumer_channel
**ust_chanp
)
428 int ret
, nr_stream_fds
, i
, j
;
430 struct ustctl_consumer_channel
*ust_channel
;
435 assert(channel
->buffer_credentials
.is_set
);
437 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
438 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
439 "switch_timer_interval: %u, read_timer_interval: %u, "
440 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
441 attr
->num_subbuf
, attr
->switch_timer_interval
,
442 attr
->read_timer_interval
, attr
->output
, attr
->type
);
444 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
)
447 nr_stream_fds
= ustctl_get_nr_stream_per_channel();
448 stream_fds
= zmalloc(nr_stream_fds
* sizeof(*stream_fds
));
453 for (i
= 0; i
< nr_stream_fds
; i
++) {
454 stream_fds
[i
] = open_ust_stream_fd(channel
, i
,
455 &channel
->buffer_credentials
.value
);
456 if (stream_fds
[i
] < 0) {
461 ust_channel
= ustctl_create_channel(attr
, stream_fds
, nr_stream_fds
);
466 channel
->nr_stream_fds
= nr_stream_fds
;
467 channel
->stream_fds
= stream_fds
;
468 *ust_chanp
= ust_channel
;
474 for (j
= i
- 1; j
>= 0; j
--) {
477 closeret
= close(stream_fds
[j
]);
481 if (channel
->shm_path
[0]) {
482 char shm_path
[PATH_MAX
];
484 closeret
= get_stream_shm_path(shm_path
,
485 channel
->shm_path
, j
);
487 ERR("Cannot get stream shm path");
489 closeret
= run_as_unlink(shm_path
,
490 channel
->buffer_credentials
.value
.uid
,
491 channel
->buffer_credentials
.value
.gid
);
493 PERROR("unlink %s", shm_path
);
497 /* Try to rmdir all directories under shm_path root. */
498 if (channel
->root_shm_path
[0]) {
499 (void) run_as_rmdir_recursive(channel
->root_shm_path
,
500 channel
->buffer_credentials
.value
.uid
,
501 channel
->buffer_credentials
.value
.gid
,
502 LTTNG_DIRECTORY_HANDLE_SKIP_NON_EMPTY_FLAG
);
510 * Send a single given stream to the session daemon using the sock.
512 * Return 0 on success else a negative value.
514 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
521 DBG("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
523 /* Send stream to session daemon. */
524 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
534 * Send channel to sessiond and relayd if applicable.
536 * Return 0 on success or else a negative value.
538 static int send_channel_to_sessiond_and_relayd(int sock
,
539 struct lttng_consumer_channel
*channel
,
540 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
542 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
543 struct lttng_consumer_stream
*stream
;
544 uint64_t net_seq_idx
= -1ULL;
550 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
552 if (channel
->relayd_id
!= (uint64_t) -1ULL) {
553 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
555 health_code_update();
557 /* Try to send the stream to the relayd if one is available. */
558 DBG("Sending stream %" PRIu64
" of channel \"%s\" to relayd",
559 stream
->key
, channel
->name
);
560 ret
= consumer_send_relayd_stream(stream
, stream
->chan
->pathname
);
563 * Flag that the relayd was the problem here probably due to a
564 * communicaton error on the socket.
569 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
571 if (net_seq_idx
== -1ULL) {
572 net_seq_idx
= stream
->net_seq_idx
;
577 /* Inform sessiond that we are about to send channel and streams. */
578 ret
= consumer_send_status_msg(sock
, ret_code
);
579 if (ret
< 0 || ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
581 * Either the session daemon is not responding or the relayd died so we
587 /* Send channel to sessiond. */
588 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
593 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
598 /* The channel was sent successfully to the sessiond at this point. */
599 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
601 health_code_update();
603 /* Send stream to session daemon. */
604 ret
= send_sessiond_stream(sock
, stream
);
610 /* Tell sessiond there is no more stream. */
611 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
616 DBG("UST consumer NULL stream sent to sessiond");
621 if (ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
628 * Creates a channel and streams and add the channel it to the channel internal
629 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
632 * Return 0 on success or else, a negative value is returned and the channel
633 * MUST be destroyed by consumer_del_channel().
635 static int ask_channel(struct lttng_consumer_local_data
*ctx
,
636 struct lttng_consumer_channel
*channel
,
637 struct ustctl_consumer_channel_attr
*attr
)
646 * This value is still used by the kernel consumer since for the kernel,
647 * the stream ownership is not IN the consumer so we need to have the
648 * number of left stream that needs to be initialized so we can know when
649 * to delete the channel (see consumer.c).
651 * As for the user space tracer now, the consumer creates and sends the
652 * stream to the session daemon which only sends them to the application
653 * once every stream of a channel is received making this value useless
654 * because we they will be added to the poll thread before the application
655 * receives them. This ensures that a stream can not hang up during
656 * initilization of a channel.
658 channel
->nb_init_stream_left
= 0;
660 /* The reply msg status is handled in the following call. */
661 ret
= create_ust_channel(channel
, attr
, &channel
->uchan
);
666 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
669 * For the snapshots (no monitor), we create the metadata streams
670 * on demand, not during the channel creation.
672 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& !channel
->monitor
) {
677 /* Open all streams for this channel. */
678 pthread_mutex_lock(&channel
->lock
);
679 ret
= create_ust_streams(channel
, ctx
);
680 pthread_mutex_unlock(&channel
->lock
);
690 * Send all stream of a channel to the right thread handling it.
692 * On error, return a negative value else 0 on success.
694 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
695 struct lttng_consumer_local_data
*ctx
)
698 struct lttng_consumer_stream
*stream
, *stmp
;
703 /* Send streams to the corresponding thread. */
704 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
707 health_code_update();
709 /* Sending the stream to the thread. */
710 ret
= send_stream_to_thread(stream
, ctx
);
713 * If we are unable to send the stream to the thread, there is
714 * a big problem so just stop everything.
725 * Flush channel's streams using the given key to retrieve the channel.
727 * Return 0 on success else an LTTng error code.
729 static int flush_channel(uint64_t chan_key
)
732 struct lttng_consumer_channel
*channel
;
733 struct lttng_consumer_stream
*stream
;
735 struct lttng_ht_iter iter
;
737 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
740 channel
= consumer_find_channel(chan_key
);
742 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
743 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
747 ht
= consumer_data
.stream_per_chan_id_ht
;
749 /* For each stream of the channel id, flush it. */
750 cds_lfht_for_each_entry_duplicate(ht
->ht
,
751 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
752 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
754 health_code_update();
756 pthread_mutex_lock(&stream
->lock
);
759 * Protect against concurrent teardown of a stream.
761 if (cds_lfht_is_node_deleted(&stream
->node
.node
)) {
765 if (!stream
->quiescent
) {
766 ustctl_flush_buffer(stream
->ustream
, 0);
767 stream
->quiescent
= true;
770 pthread_mutex_unlock(&stream
->lock
);
778 * Clear quiescent state from channel's streams using the given key to
779 * retrieve the channel.
781 * Return 0 on success else an LTTng error code.
783 static int clear_quiescent_channel(uint64_t chan_key
)
786 struct lttng_consumer_channel
*channel
;
787 struct lttng_consumer_stream
*stream
;
789 struct lttng_ht_iter iter
;
791 DBG("UST consumer clear quiescent channel key %" PRIu64
, chan_key
);
794 channel
= consumer_find_channel(chan_key
);
796 ERR("UST consumer clear quiescent channel %" PRIu64
" not found", chan_key
);
797 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
801 ht
= consumer_data
.stream_per_chan_id_ht
;
803 /* For each stream of the channel id, clear quiescent state. */
804 cds_lfht_for_each_entry_duplicate(ht
->ht
,
805 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
806 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
808 health_code_update();
810 pthread_mutex_lock(&stream
->lock
);
811 stream
->quiescent
= false;
812 pthread_mutex_unlock(&stream
->lock
);
820 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
822 * Return 0 on success else an LTTng error code.
824 static int close_metadata(uint64_t chan_key
)
827 struct lttng_consumer_channel
*channel
;
828 unsigned int channel_monitor
;
830 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
832 channel
= consumer_find_channel(chan_key
);
835 * This is possible if the metadata thread has issue a delete because
836 * the endpoint point of the stream hung up. There is no way the
837 * session daemon can know about it thus use a DBG instead of an actual
840 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
841 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
845 pthread_mutex_lock(&consumer_data
.lock
);
846 pthread_mutex_lock(&channel
->lock
);
847 channel_monitor
= channel
->monitor
;
848 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
852 lttng_ustconsumer_close_metadata(channel
);
853 pthread_mutex_unlock(&channel
->lock
);
854 pthread_mutex_unlock(&consumer_data
.lock
);
857 * The ownership of a metadata channel depends on the type of
858 * session to which it belongs. In effect, the monitor flag is checked
859 * to determine if this metadata channel is in "snapshot" mode or not.
861 * In the non-snapshot case, the metadata channel is created along with
862 * a single stream which will remain present until the metadata channel
863 * is destroyed (on the destruction of its session). In this case, the
864 * metadata stream in "monitored" by the metadata poll thread and holds
865 * the ownership of its channel.
867 * Closing the metadata will cause the metadata stream's "metadata poll
868 * pipe" to be closed. Closing this pipe will wake-up the metadata poll
869 * thread which will teardown the metadata stream which, in return,
870 * deletes the metadata channel.
872 * In the snapshot case, the metadata stream is created and destroyed
873 * on every snapshot record. Since the channel doesn't have an owner
874 * other than the session daemon, it is safe to destroy it immediately
875 * on reception of the CLOSE_METADATA command.
877 if (!channel_monitor
) {
879 * The channel and consumer_data locks must be
880 * released before this call since consumer_del_channel
881 * re-acquires the channel and consumer_data locks to teardown
882 * the channel and queue its reclamation by the "call_rcu"
885 consumer_del_channel(channel
);
890 pthread_mutex_unlock(&channel
->lock
);
891 pthread_mutex_unlock(&consumer_data
.lock
);
897 * RCU read side lock MUST be acquired before calling this function.
899 * Return 0 on success else an LTTng error code.
901 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
904 struct lttng_consumer_channel
*metadata
;
906 DBG("UST consumer setup metadata key %" PRIu64
, key
);
908 metadata
= consumer_find_channel(key
);
910 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
911 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
916 * In no monitor mode, the metadata channel has no stream(s) so skip the
917 * ownership transfer to the metadata thread.
919 if (!metadata
->monitor
) {
920 DBG("Metadata channel in no monitor");
926 * Send metadata stream to relayd if one available. Availability is
927 * known if the stream is still in the list of the channel.
929 if (cds_list_empty(&metadata
->streams
.head
)) {
930 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
931 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
932 goto error_no_stream
;
935 /* Send metadata stream to relayd if needed. */
936 if (metadata
->metadata_stream
->net_seq_idx
!= (uint64_t) -1ULL) {
937 ret
= consumer_send_relayd_stream(metadata
->metadata_stream
,
940 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
943 ret
= consumer_send_relayd_streams_sent(
944 metadata
->metadata_stream
->net_seq_idx
);
946 ret
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
952 * Ownership of metadata stream is passed along. Freeing is handled by
955 ret
= send_streams_to_thread(metadata
, ctx
);
958 * If we are unable to send the stream to the thread, there is
959 * a big problem so just stop everything.
961 ret
= LTTCOMM_CONSUMERD_FATAL
;
962 goto send_streams_error
;
964 /* List MUST be empty after or else it could be reused. */
965 assert(cds_list_empty(&metadata
->streams
.head
));
972 * Delete metadata channel on error. At this point, the metadata stream can
973 * NOT be monitored by the metadata thread thus having the guarantee that
974 * the stream is still in the local stream list of the channel. This call
975 * will make sure to clean that list.
977 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
978 cds_list_del(&metadata
->metadata_stream
->send_node
);
979 metadata
->metadata_stream
= NULL
;
987 * Snapshot the whole metadata.
988 * RCU read-side lock must be held by the caller.
990 * Returns 0 on success, < 0 on error
992 static int snapshot_metadata(struct lttng_consumer_channel
*metadata_channel
,
993 uint64_t key
, char *path
, uint64_t relayd_id
,
994 struct lttng_consumer_local_data
*ctx
)
997 struct lttng_consumer_stream
*metadata_stream
;
1002 DBG("UST consumer snapshot metadata with key %" PRIu64
" at path %s",
1007 assert(!metadata_channel
->monitor
);
1009 health_code_update();
1012 * Ask the sessiond if we have new metadata waiting and update the
1013 * consumer metadata cache.
1015 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
, 0, 1);
1020 health_code_update();
1023 * The metadata stream is NOT created in no monitor mode when the channel
1024 * is created on a sessiond ask channel command.
1026 ret
= create_ust_streams(metadata_channel
, ctx
);
1031 metadata_stream
= metadata_channel
->metadata_stream
;
1032 assert(metadata_stream
);
1034 pthread_mutex_lock(&metadata_stream
->lock
);
1035 if (relayd_id
!= (uint64_t) -1ULL) {
1036 metadata_stream
->net_seq_idx
= relayd_id
;
1037 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
1039 ret
= consumer_stream_create_output_files(metadata_stream
,
1042 pthread_mutex_unlock(&metadata_stream
->lock
);
1048 health_code_update();
1050 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
, true);
1058 * Clean up the stream completly because the next snapshot will use a new
1061 consumer_stream_destroy(metadata_stream
, NULL
);
1062 cds_list_del(&metadata_stream
->send_node
);
1063 metadata_channel
->metadata_stream
= NULL
;
1071 int get_current_subbuf_addr(struct lttng_consumer_stream
*stream
,
1075 unsigned long mmap_offset
;
1076 const char *mmap_base
;
1078 mmap_base
= ustctl_get_mmap_base(stream
->ustream
);
1080 ERR("Failed to get mmap base for stream `%s`",
1086 ret
= ustctl_get_mmap_read_offset(stream
->ustream
, &mmap_offset
);
1088 ERR("Failed to get mmap offset for stream `%s`", stream
->name
);
1093 *addr
= mmap_base
+ mmap_offset
;
1100 * Take a snapshot of all the stream of a channel.
1101 * RCU read-side lock and the channel lock must be held by the caller.
1103 * Returns 0 on success, < 0 on error
1105 static int snapshot_channel(struct lttng_consumer_channel
*channel
,
1106 uint64_t key
, char *path
, uint64_t relayd_id
,
1107 uint64_t nb_packets_per_stream
,
1108 struct lttng_consumer_local_data
*ctx
)
1111 unsigned use_relayd
= 0;
1112 unsigned long consumed_pos
, produced_pos
;
1113 struct lttng_consumer_stream
*stream
;
1120 if (relayd_id
!= (uint64_t) -1ULL) {
1124 assert(!channel
->monitor
);
1125 DBG("UST consumer snapshot channel %" PRIu64
, key
);
1127 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
1128 health_code_update();
1130 /* Lock stream because we are about to change its state. */
1131 pthread_mutex_lock(&stream
->lock
);
1132 assert(channel
->trace_chunk
);
1133 if (!lttng_trace_chunk_get(channel
->trace_chunk
)) {
1135 * Can't happen barring an internal error as the channel
1136 * holds a reference to the trace chunk.
1138 ERR("Failed to acquire reference to channel's trace chunk");
1142 assert(!stream
->trace_chunk
);
1143 stream
->trace_chunk
= channel
->trace_chunk
;
1145 stream
->net_seq_idx
= relayd_id
;
1148 ret
= consumer_send_relayd_stream(stream
, path
);
1153 ret
= consumer_stream_create_output_files(stream
,
1158 DBG("UST consumer snapshot stream (%" PRIu64
")",
1163 * If tracing is active, we want to perform a "full" buffer flush.
1164 * Else, if quiescent, it has already been done by the prior stop.
1166 if (!stream
->quiescent
) {
1167 ustctl_flush_buffer(stream
->ustream
, 0);
1170 ret
= lttng_ustconsumer_take_snapshot(stream
);
1172 ERR("Taking UST snapshot");
1176 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
1178 ERR("Produced UST snapshot position");
1182 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
1184 ERR("Consumerd UST snapshot position");
1189 * The original value is sent back if max stream size is larger than
1190 * the possible size of the snapshot. Also, we assume that the session
1191 * daemon should never send a maximum stream size that is lower than
1194 consumed_pos
= consumer_get_consume_start_pos(consumed_pos
,
1195 produced_pos
, nb_packets_per_stream
,
1196 stream
->max_sb_size
);
1198 while ((long) (consumed_pos
- produced_pos
) < 0) {
1200 unsigned long len
, padded_len
;
1201 const char *subbuf_addr
;
1202 struct lttng_buffer_view subbuf_view
;
1204 health_code_update();
1206 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
1208 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
1210 if (ret
!= -EAGAIN
) {
1211 PERROR("ustctl_get_subbuf snapshot");
1212 goto error_close_stream
;
1214 DBG("UST consumer get subbuf failed. Skipping it.");
1215 consumed_pos
+= stream
->max_sb_size
;
1216 stream
->chan
->lost_packets
++;
1220 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
1222 ERR("Snapshot ustctl_get_subbuf_size");
1223 goto error_put_subbuf
;
1226 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
1228 ERR("Snapshot ustctl_get_padded_subbuf_size");
1229 goto error_put_subbuf
;
1232 ret
= get_current_subbuf_addr(stream
, &subbuf_addr
);
1234 goto error_put_subbuf
;
1237 subbuf_view
= lttng_buffer_view_init(
1238 subbuf_addr
, 0, padded_len
);
1239 read_len
= lttng_consumer_on_read_subbuffer_mmap(
1240 stream
, &subbuf_view
, padded_len
- len
);
1242 if (read_len
!= len
) {
1244 goto error_put_subbuf
;
1247 if (read_len
!= padded_len
) {
1249 goto error_put_subbuf
;
1253 ret
= ustctl_put_subbuf(stream
->ustream
);
1255 ERR("Snapshot ustctl_put_subbuf");
1256 goto error_close_stream
;
1258 consumed_pos
+= stream
->max_sb_size
;
1261 /* Simply close the stream so we can use it on the next snapshot. */
1262 consumer_stream_close(stream
);
1263 pthread_mutex_unlock(&stream
->lock
);
1270 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
1271 ERR("Snapshot ustctl_put_subbuf");
1274 consumer_stream_close(stream
);
1276 pthread_mutex_unlock(&stream
->lock
);
1282 * Receive the metadata updates from the sessiond. Supports receiving
1283 * overlapping metadata, but is needs to always belong to a contiguous
1284 * range starting from 0.
1285 * Be careful about the locks held when calling this function: it needs
1286 * the metadata cache flush to concurrently progress in order to
1289 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
1290 uint64_t len
, uint64_t version
,
1291 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
1293 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1296 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
1298 metadata_str
= zmalloc(len
* sizeof(char));
1299 if (!metadata_str
) {
1300 PERROR("zmalloc metadata string");
1301 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
1305 health_code_update();
1307 /* Receive metadata string. */
1308 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1310 /* Session daemon is dead so return gracefully. */
1315 health_code_update();
1317 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1318 ret
= consumer_metadata_cache_write(channel
, offset
, len
, version
,
1320 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1322 /* Unable to handle metadata. Notify session daemon. */
1323 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1325 * Skip metadata flush on write error since the offset and len might
1326 * not have been updated which could create an infinite loop below when
1327 * waiting for the metadata cache to be flushed.
1335 while (consumer_metadata_cache_flushed(channel
, offset
+ len
, timer
)) {
1336 DBG("Waiting for metadata to be flushed");
1338 health_code_update();
1340 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1350 * Receive command from session daemon and process it.
1352 * Return 1 on success else a negative value or 0.
1354 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1355 int sock
, struct pollfd
*consumer_sockpoll
)
1358 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1359 struct lttcomm_consumer_msg msg
;
1360 struct lttng_consumer_channel
*channel
= NULL
;
1362 health_code_update();
1364 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1365 if (ret
!= sizeof(msg
)) {
1366 DBG("Consumer received unexpected message size %zd (expects %zu)",
1369 * The ret value might 0 meaning an orderly shutdown but this is ok
1370 * since the caller handles this.
1373 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1379 health_code_update();
1382 assert(msg
.cmd_type
!= LTTNG_CONSUMER_STOP
);
1384 health_code_update();
1386 /* relayd needs RCU read-side lock */
1389 switch (msg
.cmd_type
) {
1390 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1392 /* Session daemon status message are handled in the following call. */
1393 consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1394 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1395 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
,
1396 msg
.u
.relayd_sock
.relayd_session_id
);
1399 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1401 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1402 struct consumer_relayd_sock_pair
*relayd
;
1404 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1406 /* Get relayd reference if exists. */
1407 relayd
= consumer_find_relayd(index
);
1408 if (relayd
== NULL
) {
1409 DBG("Unable to find relayd %" PRIu64
, index
);
1410 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
1414 * Each relayd socket pair has a refcount of stream attached to it
1415 * which tells if the relayd is still active or not depending on the
1418 * This will set the destroy flag of the relayd object and destroy it
1419 * if the refcount reaches zero when called.
1421 * The destroy can happen either here or when a stream fd hangs up.
1424 consumer_flag_relayd_for_destroy(relayd
);
1427 goto end_msg_sessiond
;
1429 case LTTNG_CONSUMER_UPDATE_STREAM
:
1434 case LTTNG_CONSUMER_DATA_PENDING
:
1436 int ret
, is_data_pending
;
1437 uint64_t id
= msg
.u
.data_pending
.session_id
;
1439 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1441 is_data_pending
= consumer_data_pending(id
);
1443 /* Send back returned value to session daemon */
1444 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1445 sizeof(is_data_pending
));
1447 DBG("Error when sending the data pending ret code: %d", ret
);
1452 * No need to send back a status message since the data pending
1453 * returned value is the response.
1457 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1460 struct ustctl_consumer_channel_attr attr
;
1461 const uint64_t chunk_id
= msg
.u
.ask_channel
.chunk_id
.value
;
1462 const struct lttng_credentials buffer_credentials
= {
1463 .uid
= msg
.u
.ask_channel
.buffer_credentials
.uid
,
1464 .gid
= msg
.u
.ask_channel
.buffer_credentials
.gid
,
1467 /* Create a plain object and reserve a channel key. */
1468 channel
= consumer_allocate_channel(
1469 msg
.u
.ask_channel
.key
,
1470 msg
.u
.ask_channel
.session_id
,
1471 msg
.u
.ask_channel
.chunk_id
.is_set
?
1473 msg
.u
.ask_channel
.pathname
,
1474 msg
.u
.ask_channel
.name
,
1475 msg
.u
.ask_channel
.relayd_id
,
1476 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1477 msg
.u
.ask_channel
.tracefile_size
,
1478 msg
.u
.ask_channel
.tracefile_count
,
1479 msg
.u
.ask_channel
.session_id_per_pid
,
1480 msg
.u
.ask_channel
.monitor
,
1481 msg
.u
.ask_channel
.live_timer_interval
,
1482 msg
.u
.ask_channel
.is_live
,
1483 msg
.u
.ask_channel
.root_shm_path
,
1484 msg
.u
.ask_channel
.shm_path
);
1486 goto end_channel_error
;
1489 LTTNG_OPTIONAL_SET(&channel
->buffer_credentials
,
1490 buffer_credentials
);
1493 * Assign UST application UID to the channel. This value is ignored for
1494 * per PID buffers. This is specific to UST thus setting this after the
1497 channel
->ust_app_uid
= msg
.u
.ask_channel
.ust_app_uid
;
1499 /* Build channel attributes from received message. */
1500 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1501 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1502 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1503 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1504 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1505 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1506 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1507 attr
.blocking_timeout
= msg
.u
.ask_channel
.blocking_timeout
;
1509 /* Match channel buffer type to the UST abi. */
1510 switch (msg
.u
.ask_channel
.output
) {
1511 case LTTNG_EVENT_MMAP
:
1513 attr
.output
= LTTNG_UST_MMAP
;
1517 /* Translate and save channel type. */
1518 switch (msg
.u
.ask_channel
.type
) {
1519 case LTTNG_UST_CHAN_PER_CPU
:
1520 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1521 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1523 * Set refcount to 1 for owner. Below, we will
1524 * pass ownership to the
1525 * consumer_thread_channel_poll() thread.
1527 channel
->refcount
= 1;
1529 case LTTNG_UST_CHAN_METADATA
:
1530 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1531 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1538 health_code_update();
1540 ret
= ask_channel(ctx
, channel
, &attr
);
1542 goto end_channel_error
;
1545 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1546 ret
= consumer_metadata_cache_allocate(channel
);
1548 ERR("Allocating metadata cache");
1549 goto end_channel_error
;
1551 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1552 attr
.switch_timer_interval
= 0;
1554 int monitor_start_ret
;
1556 consumer_timer_live_start(channel
,
1557 msg
.u
.ask_channel
.live_timer_interval
);
1558 monitor_start_ret
= consumer_timer_monitor_start(
1560 msg
.u
.ask_channel
.monitor_timer_interval
);
1561 if (monitor_start_ret
< 0) {
1562 ERR("Starting channel monitoring timer failed");
1563 goto end_channel_error
;
1567 health_code_update();
1570 * Add the channel to the internal state AFTER all streams were created
1571 * and successfully sent to session daemon. This way, all streams must
1572 * be ready before this channel is visible to the threads.
1573 * If add_channel succeeds, ownership of the channel is
1574 * passed to consumer_thread_channel_poll().
1576 ret
= add_channel(channel
, ctx
);
1578 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1579 if (channel
->switch_timer_enabled
== 1) {
1580 consumer_timer_switch_stop(channel
);
1582 consumer_metadata_cache_destroy(channel
);
1584 if (channel
->live_timer_enabled
== 1) {
1585 consumer_timer_live_stop(channel
);
1587 if (channel
->monitor_timer_enabled
== 1) {
1588 consumer_timer_monitor_stop(channel
);
1590 goto end_channel_error
;
1593 health_code_update();
1596 * Channel and streams are now created. Inform the session daemon that
1597 * everything went well and should wait to receive the channel and
1598 * streams with ustctl API.
1600 ret
= consumer_send_status_channel(sock
, channel
);
1603 * There is probably a problem on the socket.
1610 case LTTNG_CONSUMER_GET_CHANNEL
:
1612 int ret
, relayd_err
= 0;
1613 uint64_t key
= msg
.u
.get_channel
.key
;
1614 struct lttng_consumer_channel
*channel
;
1616 channel
= consumer_find_channel(key
);
1618 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1619 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1620 goto end_get_channel
;
1623 health_code_update();
1625 /* Send the channel to sessiond (and relayd, if applicable). */
1626 ret
= send_channel_to_sessiond_and_relayd(sock
, channel
, ctx
,
1631 * We were unable to send to the relayd the stream so avoid
1632 * sending back a fatal error to the thread since this is OK
1633 * and the consumer can continue its work. The above call
1634 * has sent the error status message to the sessiond.
1636 goto end_get_channel_nosignal
;
1639 * The communicaton was broken hence there is a bad state between
1640 * the consumer and sessiond so stop everything.
1642 goto error_get_channel_fatal
;
1645 health_code_update();
1648 * In no monitor mode, the streams ownership is kept inside the channel
1649 * so don't send them to the data thread.
1651 if (!channel
->monitor
) {
1652 goto end_get_channel
;
1655 ret
= send_streams_to_thread(channel
, ctx
);
1658 * If we are unable to send the stream to the thread, there is
1659 * a big problem so just stop everything.
1661 goto error_get_channel_fatal
;
1663 /* List MUST be empty after or else it could be reused. */
1664 assert(cds_list_empty(&channel
->streams
.head
));
1666 goto end_msg_sessiond
;
1667 error_get_channel_fatal
:
1669 end_get_channel_nosignal
:
1672 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1674 uint64_t key
= msg
.u
.destroy_channel
.key
;
1677 * Only called if streams have not been sent to stream
1678 * manager thread. However, channel has been sent to
1679 * channel manager thread.
1681 notify_thread_del_channel(ctx
, key
);
1682 goto end_msg_sessiond
;
1684 case LTTNG_CONSUMER_CLOSE_METADATA
:
1688 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1693 goto end_msg_sessiond
;
1695 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1699 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1704 goto end_msg_sessiond
;
1706 case LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL
:
1710 ret
= clear_quiescent_channel(
1711 msg
.u
.clear_quiescent_channel
.key
);
1716 goto end_msg_sessiond
;
1718 case LTTNG_CONSUMER_PUSH_METADATA
:
1721 uint64_t len
= msg
.u
.push_metadata
.len
;
1722 uint64_t key
= msg
.u
.push_metadata
.key
;
1723 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1724 uint64_t version
= msg
.u
.push_metadata
.version
;
1725 struct lttng_consumer_channel
*channel
;
1727 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1730 channel
= consumer_find_channel(key
);
1733 * This is possible if the metadata creation on the consumer side
1734 * is in flight vis-a-vis a concurrent push metadata from the
1735 * session daemon. Simply return that the channel failed and the
1736 * session daemon will handle that message correctly considering
1737 * that this race is acceptable thus the DBG() statement here.
1739 DBG("UST consumer push metadata %" PRIu64
" not found", key
);
1740 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1741 goto end_push_metadata_msg_sessiond
;
1744 health_code_update();
1748 * There is nothing to receive. We have simply
1749 * checked whether the channel can be found.
1751 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1752 goto end_push_metadata_msg_sessiond
;
1755 /* Tell session daemon we are ready to receive the metadata. */
1756 ret
= consumer_send_status_msg(sock
, LTTCOMM_CONSUMERD_SUCCESS
);
1758 /* Somehow, the session daemon is not responding anymore. */
1759 goto error_push_metadata_fatal
;
1762 health_code_update();
1764 /* Wait for more data. */
1765 health_poll_entry();
1766 ret
= lttng_consumer_poll_socket(consumer_sockpoll
);
1769 goto error_push_metadata_fatal
;
1772 health_code_update();
1774 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1775 len
, version
, channel
, 0, 1);
1777 /* error receiving from sessiond */
1778 goto error_push_metadata_fatal
;
1781 goto end_push_metadata_msg_sessiond
;
1783 end_push_metadata_msg_sessiond
:
1784 goto end_msg_sessiond
;
1785 error_push_metadata_fatal
:
1788 case LTTNG_CONSUMER_SETUP_METADATA
:
1792 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1796 goto end_msg_sessiond
;
1798 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1800 struct lttng_consumer_channel
*channel
;
1801 uint64_t key
= msg
.u
.snapshot_channel
.key
;
1803 channel
= consumer_find_channel(key
);
1805 DBG("UST snapshot channel not found for key %" PRIu64
, key
);
1806 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1808 if (msg
.u
.snapshot_channel
.metadata
) {
1809 ret
= snapshot_metadata(channel
, key
,
1810 msg
.u
.snapshot_channel
.pathname
,
1811 msg
.u
.snapshot_channel
.relayd_id
,
1814 ERR("Snapshot metadata failed");
1815 ret_code
= LTTCOMM_CONSUMERD_SNAPSHOT_FAILED
;
1818 ret
= snapshot_channel(channel
, key
,
1819 msg
.u
.snapshot_channel
.pathname
,
1820 msg
.u
.snapshot_channel
.relayd_id
,
1821 msg
.u
.snapshot_channel
.nb_packets_per_stream
,
1824 ERR("Snapshot channel failed");
1825 ret_code
= LTTCOMM_CONSUMERD_SNAPSHOT_FAILED
;
1829 health_code_update();
1830 ret
= consumer_send_status_msg(sock
, ret_code
);
1832 /* Somehow, the session daemon is not responding anymore. */
1835 health_code_update();
1838 case LTTNG_CONSUMER_DISCARDED_EVENTS
:
1841 uint64_t discarded_events
;
1842 struct lttng_ht_iter iter
;
1843 struct lttng_ht
*ht
;
1844 struct lttng_consumer_stream
*stream
;
1845 uint64_t id
= msg
.u
.discarded_events
.session_id
;
1846 uint64_t key
= msg
.u
.discarded_events
.channel_key
;
1848 DBG("UST consumer discarded events command for session id %"
1851 pthread_mutex_lock(&consumer_data
.lock
);
1853 ht
= consumer_data
.stream_list_ht
;
1856 * We only need a reference to the channel, but they are not
1857 * directly indexed, so we just use the first matching stream
1858 * to extract the information we need, we default to 0 if not
1859 * found (no events are dropped if the channel is not yet in
1862 discarded_events
= 0;
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 discarded_events
= stream
->chan
->discarded_events
;
1872 pthread_mutex_unlock(&consumer_data
.lock
);
1875 DBG("UST consumer discarded events 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
, &discarded_events
, sizeof(discarded_events
));
1883 PERROR("send discarded events");
1889 case LTTNG_CONSUMER_LOST_PACKETS
:
1892 uint64_t lost_packets
;
1893 struct lttng_ht_iter iter
;
1894 struct lttng_ht
*ht
;
1895 struct lttng_consumer_stream
*stream
;
1896 uint64_t id
= msg
.u
.lost_packets
.session_id
;
1897 uint64_t key
= msg
.u
.lost_packets
.channel_key
;
1899 DBG("UST consumer lost packets command for session id %"
1902 pthread_mutex_lock(&consumer_data
.lock
);
1904 ht
= consumer_data
.stream_list_ht
;
1907 * We only need a reference to the channel, but they are not
1908 * directly indexed, so we just use the first matching stream
1909 * to extract the information we need, we default to 0 if not
1910 * found (no packets lost if the channel is not yet in use).
1913 cds_lfht_for_each_entry_duplicate(ht
->ht
,
1914 ht
->hash_fct(&id
, lttng_ht_seed
),
1916 &iter
.iter
, stream
, node_session_id
.node
) {
1917 if (stream
->chan
->key
== key
) {
1918 lost_packets
= stream
->chan
->lost_packets
;
1922 pthread_mutex_unlock(&consumer_data
.lock
);
1925 DBG("UST consumer lost packets command for session id %"
1926 PRIu64
", channel key %" PRIu64
, id
, key
);
1928 health_code_update();
1930 /* Send back returned value to session daemon */
1931 ret
= lttcomm_send_unix_sock(sock
, &lost_packets
,
1932 sizeof(lost_packets
));
1934 PERROR("send lost packets");
1940 case LTTNG_CONSUMER_SET_CHANNEL_MONITOR_PIPE
:
1942 int channel_monitor_pipe
;
1944 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1945 /* Successfully received the command's type. */
1946 ret
= consumer_send_status_msg(sock
, ret_code
);
1951 ret
= lttcomm_recv_fds_unix_sock(sock
, &channel_monitor_pipe
,
1953 if (ret
!= sizeof(channel_monitor_pipe
)) {
1954 ERR("Failed to receive channel monitor pipe");
1958 DBG("Received channel monitor pipe (%d)", channel_monitor_pipe
);
1959 ret
= consumer_timer_thread_set_channel_monitor_pipe(
1960 channel_monitor_pipe
);
1964 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1965 /* Set the pipe as non-blocking. */
1966 ret
= fcntl(channel_monitor_pipe
, F_GETFL
, 0);
1968 PERROR("fcntl get flags of the channel monitoring pipe");
1973 ret
= fcntl(channel_monitor_pipe
, F_SETFL
,
1974 flags
| O_NONBLOCK
);
1976 PERROR("fcntl set O_NONBLOCK flag of the channel monitoring pipe");
1979 DBG("Channel monitor pipe set as non-blocking");
1981 ret_code
= LTTCOMM_CONSUMERD_ALREADY_SET
;
1983 goto end_msg_sessiond
;
1985 case LTTNG_CONSUMER_ROTATE_CHANNEL
:
1987 struct lttng_consumer_channel
*channel
;
1988 uint64_t key
= msg
.u
.rotate_channel
.key
;
1990 channel
= consumer_find_channel(key
);
1992 DBG("Channel %" PRIu64
" not found", key
);
1993 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1996 * Sample the rotate position of all the streams in
1999 ret
= lttng_consumer_rotate_channel(channel
, key
,
2000 msg
.u
.rotate_channel
.relayd_id
,
2001 msg
.u
.rotate_channel
.metadata
,
2004 ERR("Rotate channel failed");
2005 ret_code
= LTTCOMM_CONSUMERD_ROTATION_FAIL
;
2008 health_code_update();
2010 ret
= consumer_send_status_msg(sock
, ret_code
);
2012 /* Somehow, the session daemon is not responding anymore. */
2013 goto end_rotate_channel_nosignal
;
2017 * Rotate the streams that are ready right now.
2018 * FIXME: this is a second consecutive iteration over the
2019 * streams in a channel, there is probably a better way to
2020 * handle this, but it needs to be after the
2021 * consumer_send_status_msg() call.
2024 ret
= lttng_consumer_rotate_ready_streams(
2027 ERR("Rotate channel failed");
2031 end_rotate_channel_nosignal
:
2034 case LTTNG_CONSUMER_CLEAR_CHANNEL
:
2036 struct lttng_consumer_channel
*channel
;
2037 uint64_t key
= msg
.u
.clear_channel
.key
;
2039 channel
= consumer_find_channel(key
);
2041 DBG("Channel %" PRIu64
" not found", key
);
2042 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
2044 ret
= lttng_consumer_clear_channel(channel
);
2046 ERR("Clear channel failed key %" PRIu64
, key
);
2050 health_code_update();
2052 ret
= consumer_send_status_msg(sock
, ret_code
);
2054 /* Somehow, the session daemon is not responding anymore. */
2059 case LTTNG_CONSUMER_INIT
:
2061 ret_code
= lttng_consumer_init_command(ctx
,
2062 msg
.u
.init
.sessiond_uuid
);
2063 health_code_update();
2064 ret
= consumer_send_status_msg(sock
, ret_code
);
2066 /* Somehow, the session daemon is not responding anymore. */
2071 case LTTNG_CONSUMER_CREATE_TRACE_CHUNK
:
2073 const struct lttng_credentials credentials
= {
2074 .uid
= msg
.u
.create_trace_chunk
.credentials
.value
.uid
,
2075 .gid
= msg
.u
.create_trace_chunk
.credentials
.value
.gid
,
2077 const bool is_local_trace
=
2078 !msg
.u
.create_trace_chunk
.relayd_id
.is_set
;
2079 const uint64_t relayd_id
=
2080 msg
.u
.create_trace_chunk
.relayd_id
.value
;
2081 const char *chunk_override_name
=
2082 *msg
.u
.create_trace_chunk
.override_name
?
2083 msg
.u
.create_trace_chunk
.override_name
:
2085 struct lttng_directory_handle
*chunk_directory_handle
= NULL
;
2088 * The session daemon will only provide a chunk directory file
2089 * descriptor for local traces.
2091 if (is_local_trace
) {
2094 /* Acnowledge the reception of the command. */
2095 ret
= consumer_send_status_msg(sock
,
2096 LTTCOMM_CONSUMERD_SUCCESS
);
2098 /* Somehow, the session daemon is not responding anymore. */
2103 * Receive trace chunk domain dirfd.
2105 ret
= lttcomm_recv_fds_unix_sock(sock
, &chunk_dirfd
, 1);
2106 if (ret
!= sizeof(chunk_dirfd
)) {
2107 ERR("Failed to receive trace chunk domain directory file descriptor");
2111 DBG("Received trace chunk domain directory fd (%d)",
2113 chunk_directory_handle
= lttng_directory_handle_create_from_dirfd(
2115 if (!chunk_directory_handle
) {
2116 ERR("Failed to initialize chunk domain directory handle from directory file descriptor");
2117 if (close(chunk_dirfd
)) {
2118 PERROR("Failed to close chunk directory file descriptor");
2124 ret_code
= lttng_consumer_create_trace_chunk(
2125 !is_local_trace
? &relayd_id
: NULL
,
2126 msg
.u
.create_trace_chunk
.session_id
,
2127 msg
.u
.create_trace_chunk
.chunk_id
,
2128 (time_t) msg
.u
.create_trace_chunk
2129 .creation_timestamp
,
2130 chunk_override_name
,
2131 msg
.u
.create_trace_chunk
.credentials
.is_set
?
2134 chunk_directory_handle
);
2135 lttng_directory_handle_put(chunk_directory_handle
);
2136 goto end_msg_sessiond
;
2138 case LTTNG_CONSUMER_CLOSE_TRACE_CHUNK
:
2140 enum lttng_trace_chunk_command_type close_command
=
2141 msg
.u
.close_trace_chunk
.close_command
.value
;
2142 const uint64_t relayd_id
=
2143 msg
.u
.close_trace_chunk
.relayd_id
.value
;
2144 struct lttcomm_consumer_close_trace_chunk_reply reply
;
2145 char closed_trace_chunk_path
[LTTNG_PATH_MAX
];
2148 ret_code
= lttng_consumer_close_trace_chunk(
2149 msg
.u
.close_trace_chunk
.relayd_id
.is_set
?
2152 msg
.u
.close_trace_chunk
.session_id
,
2153 msg
.u
.close_trace_chunk
.chunk_id
,
2154 (time_t) msg
.u
.close_trace_chunk
.close_timestamp
,
2155 msg
.u
.close_trace_chunk
.close_command
.is_set
?
2157 NULL
, closed_trace_chunk_path
);
2158 reply
.ret_code
= ret_code
;
2159 reply
.path_length
= strlen(closed_trace_chunk_path
) + 1;
2160 ret
= lttcomm_send_unix_sock(sock
, &reply
, sizeof(reply
));
2161 if (ret
!= sizeof(reply
)) {
2164 ret
= lttcomm_send_unix_sock(sock
, closed_trace_chunk_path
,
2166 if (ret
!= reply
.path_length
) {
2171 case LTTNG_CONSUMER_TRACE_CHUNK_EXISTS
:
2173 const uint64_t relayd_id
=
2174 msg
.u
.trace_chunk_exists
.relayd_id
.value
;
2176 ret_code
= lttng_consumer_trace_chunk_exists(
2177 msg
.u
.trace_chunk_exists
.relayd_id
.is_set
?
2179 msg
.u
.trace_chunk_exists
.session_id
,
2180 msg
.u
.trace_chunk_exists
.chunk_id
);
2181 goto end_msg_sessiond
;
2183 case LTTNG_CONSUMER_OPEN_CHANNEL_PACKETS
:
2185 const uint64_t key
= msg
.u
.open_channel_packets
.key
;
2186 struct lttng_consumer_channel
*channel
=
2187 consumer_find_channel(key
);
2190 pthread_mutex_lock(&channel
->lock
);
2191 ret_code
= lttng_consumer_open_channel_packets(channel
);
2192 pthread_mutex_unlock(&channel
->lock
);
2195 * The channel could have disappeared in per-pid
2198 DBG("Channel %" PRIu64
" not found", key
);
2199 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
2202 health_code_update();
2203 goto end_msg_sessiond
;
2211 * Return 1 to indicate success since the 0 value can be a socket
2212 * shutdown during the recv() or send() call.
2219 * The returned value here is not useful since either way we'll return 1 to
2220 * the caller because the session daemon socket management is done
2221 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
2223 ret
= consumer_send_status_msg(sock
, ret_code
);
2233 * Free channel here since no one has a reference to it. We don't
2234 * free after that because a stream can store this pointer.
2236 destroy_channel(channel
);
2238 /* We have to send a status channel message indicating an error. */
2239 ret
= consumer_send_status_channel(sock
, NULL
);
2241 /* Stop everything if session daemon can not be notified. */
2248 /* This will issue a consumer stop. */
2254 health_code_update();
2258 void lttng_ustctl_flush_buffer(struct lttng_consumer_stream
*stream
,
2259 int producer_active
)
2262 assert(stream
->ustream
);
2264 ustctl_flush_buffer(stream
->ustream
, producer_active
);
2268 * Take a snapshot for a specific stream.
2270 * Returns 0 on success, < 0 on error
2272 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
2275 assert(stream
->ustream
);
2277 return ustctl_snapshot(stream
->ustream
);
2281 * Sample consumed and produced positions for a specific stream.
2283 * Returns 0 on success, < 0 on error.
2285 int lttng_ustconsumer_sample_snapshot_positions(
2286 struct lttng_consumer_stream
*stream
)
2289 assert(stream
->ustream
);
2291 return ustctl_snapshot_sample_positions(stream
->ustream
);
2295 * Get the produced position
2297 * Returns 0 on success, < 0 on error
2299 int lttng_ustconsumer_get_produced_snapshot(
2300 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
2303 assert(stream
->ustream
);
2306 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
2310 * Get the consumed position
2312 * Returns 0 on success, < 0 on error
2314 int lttng_ustconsumer_get_consumed_snapshot(
2315 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
2318 assert(stream
->ustream
);
2321 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
2324 void lttng_ustconsumer_flush_buffer(struct lttng_consumer_stream
*stream
,
2328 assert(stream
->ustream
);
2330 ustctl_flush_buffer(stream
->ustream
, producer
);
2333 void lttng_ustconsumer_clear_buffer(struct lttng_consumer_stream
*stream
)
2336 assert(stream
->ustream
);
2338 ustctl_clear_buffer(stream
->ustream
);
2341 int lttng_ustconsumer_get_current_timestamp(
2342 struct lttng_consumer_stream
*stream
, uint64_t *ts
)
2345 assert(stream
->ustream
);
2348 return ustctl_get_current_timestamp(stream
->ustream
, ts
);
2351 int lttng_ustconsumer_get_sequence_number(
2352 struct lttng_consumer_stream
*stream
, uint64_t *seq
)
2355 assert(stream
->ustream
);
2358 return ustctl_get_sequence_number(stream
->ustream
, seq
);
2362 * Called when the stream signals the consumer that it has hung up.
2364 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
2367 assert(stream
->ustream
);
2369 pthread_mutex_lock(&stream
->lock
);
2370 if (!stream
->quiescent
) {
2371 ustctl_flush_buffer(stream
->ustream
, 0);
2372 stream
->quiescent
= true;
2374 pthread_mutex_unlock(&stream
->lock
);
2375 stream
->hangup_flush_done
= 1;
2378 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
2383 assert(chan
->uchan
);
2384 assert(chan
->buffer_credentials
.is_set
);
2386 if (chan
->switch_timer_enabled
== 1) {
2387 consumer_timer_switch_stop(chan
);
2389 for (i
= 0; i
< chan
->nr_stream_fds
; i
++) {
2392 ret
= close(chan
->stream_fds
[i
]);
2396 if (chan
->shm_path
[0]) {
2397 char shm_path
[PATH_MAX
];
2399 ret
= get_stream_shm_path(shm_path
, chan
->shm_path
, i
);
2401 ERR("Cannot get stream shm path");
2403 ret
= run_as_unlink(shm_path
,
2404 chan
->buffer_credentials
.value
.uid
,
2405 chan
->buffer_credentials
.value
.gid
);
2407 PERROR("unlink %s", shm_path
);
2413 void lttng_ustconsumer_free_channel(struct lttng_consumer_channel
*chan
)
2416 assert(chan
->uchan
);
2417 assert(chan
->buffer_credentials
.is_set
);
2419 consumer_metadata_cache_destroy(chan
);
2420 ustctl_destroy_channel(chan
->uchan
);
2421 /* Try to rmdir all directories under shm_path root. */
2422 if (chan
->root_shm_path
[0]) {
2423 (void) run_as_rmdir_recursive(chan
->root_shm_path
,
2424 chan
->buffer_credentials
.value
.uid
,
2425 chan
->buffer_credentials
.value
.gid
,
2426 LTTNG_DIRECTORY_HANDLE_SKIP_NON_EMPTY_FLAG
);
2428 free(chan
->stream_fds
);
2431 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
2434 assert(stream
->ustream
);
2436 if (stream
->chan
->switch_timer_enabled
== 1) {
2437 consumer_timer_switch_stop(stream
->chan
);
2439 ustctl_destroy_stream(stream
->ustream
);
2442 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream
*stream
)
2445 assert(stream
->ustream
);
2447 return ustctl_stream_get_wakeup_fd(stream
->ustream
);
2450 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream
*stream
)
2453 assert(stream
->ustream
);
2455 return ustctl_stream_close_wakeup_fd(stream
->ustream
);
2459 void metadata_stream_reset_cache_consumed_position(
2460 struct lttng_consumer_stream
*stream
)
2462 DBG("Reset metadata cache of session %" PRIu64
,
2463 stream
->chan
->session_id
);
2464 stream
->ust_metadata_pushed
= 0;
2468 * Write up to one packet from the metadata cache to the channel.
2470 * Returns the number of bytes pushed from the cache into the ring buffer, or a
2471 * negative value on error.
2474 int commit_one_metadata_packet(struct lttng_consumer_stream
*stream
)
2479 pthread_mutex_lock(&stream
->chan
->metadata_cache
->lock
);
2480 if (stream
->chan
->metadata_cache
->max_offset
==
2481 stream
->ust_metadata_pushed
) {
2483 * In the context of a user space metadata channel, a
2484 * change in version can be detected in two ways:
2485 * 1) During the pre-consume of the `read_subbuffer` loop,
2486 * 2) When populating the metadata ring buffer (i.e. here).
2488 * This function is invoked when there is no metadata
2489 * available in the ring-buffer. If all data was consumed
2490 * up to the size of the metadata cache, there is no metadata
2491 * to insert in the ring-buffer.
2493 * However, the metadata version could still have changed (a
2494 * regeneration without any new data will yield the same cache
2497 * The cache's version is checked for a version change and the
2498 * consumed position is reset if one occurred.
2500 * This check is only necessary for the user space domain as
2501 * it has to manage the cache explicitly. If this reset was not
2502 * performed, no metadata would be consumed (and no reset would
2503 * occur as part of the pre-consume) until the metadata size
2504 * exceeded the cache size.
2506 if (stream
->metadata_version
!=
2507 stream
->chan
->metadata_cache
->version
) {
2508 metadata_stream_reset_cache_consumed_position(stream
);
2509 consumer_stream_metadata_set_version(stream
,
2510 stream
->chan
->metadata_cache
->version
);
2517 write_len
= ustctl_write_one_packet_to_channel(stream
->chan
->uchan
,
2518 &stream
->chan
->metadata_cache
->data
[stream
->ust_metadata_pushed
],
2519 stream
->chan
->metadata_cache
->max_offset
2520 - stream
->ust_metadata_pushed
);
2521 assert(write_len
!= 0);
2522 if (write_len
< 0) {
2523 ERR("Writing one metadata packet");
2527 stream
->ust_metadata_pushed
+= write_len
;
2529 assert(stream
->chan
->metadata_cache
->max_offset
>=
2530 stream
->ust_metadata_pushed
);
2534 * Switch packet (but don't open the next one) on every commit of
2535 * a metadata packet. Since the subbuffer is fully filled (with padding,
2536 * if needed), the stream is "quiescent" after this commit.
2538 ustctl_flush_buffer(stream
->ustream
, 1);
2539 stream
->quiescent
= true;
2541 pthread_mutex_unlock(&stream
->chan
->metadata_cache
->lock
);
2547 * Sync metadata meaning request them to the session daemon and snapshot to the
2548 * metadata thread can consumer them.
2550 * Metadata stream lock is held here, but we need to release it when
2551 * interacting with sessiond, else we cause a deadlock with live
2552 * awaiting on metadata to be pushed out.
2554 * The RCU read side lock must be held by the caller.
2556 enum sync_metadata_status
lttng_ustconsumer_sync_metadata(
2557 struct lttng_consumer_local_data
*ctx
,
2558 struct lttng_consumer_stream
*metadata_stream
)
2561 enum sync_metadata_status status
;
2562 struct lttng_consumer_channel
*metadata_channel
;
2565 assert(metadata_stream
);
2567 metadata_channel
= metadata_stream
->chan
;
2568 pthread_mutex_unlock(&metadata_stream
->lock
);
2570 * Request metadata from the sessiond, but don't wait for the flush
2571 * because we locked the metadata thread.
2573 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
, 0, 0);
2574 pthread_mutex_lock(&metadata_stream
->lock
);
2576 status
= SYNC_METADATA_STATUS_ERROR
;
2581 * The metadata stream and channel can be deleted while the
2582 * metadata stream lock was released. The streamed is checked
2583 * for deletion before we use it further.
2585 * Note that it is safe to access a logically-deleted stream since its
2586 * existence is still guaranteed by the RCU read side lock. However,
2587 * it should no longer be used. The close/deletion of the metadata
2588 * channel and stream already guarantees that all metadata has been
2589 * consumed. Therefore, there is nothing left to do in this function.
2591 if (consumer_stream_is_deleted(metadata_stream
)) {
2592 DBG("Metadata stream %" PRIu64
" was deleted during the metadata synchronization",
2593 metadata_stream
->key
);
2594 status
= SYNC_METADATA_STATUS_NO_DATA
;
2598 ret
= commit_one_metadata_packet(metadata_stream
);
2600 status
= SYNC_METADATA_STATUS_ERROR
;
2602 } else if (ret
> 0) {
2603 status
= SYNC_METADATA_STATUS_NEW_DATA
;
2604 } else /* ret == 0 */ {
2605 status
= SYNC_METADATA_STATUS_NO_DATA
;
2609 ret
= ustctl_snapshot(metadata_stream
->ustream
);
2611 ERR("Failed to take a snapshot of the metadata ring-buffer positions, ret = %d", ret
);
2612 status
= SYNC_METADATA_STATUS_ERROR
;
2621 * Return 0 on success else a negative value.
2623 static int notify_if_more_data(struct lttng_consumer_stream
*stream
,
2624 struct lttng_consumer_local_data
*ctx
)
2627 struct ustctl_consumer_stream
*ustream
;
2632 ustream
= stream
->ustream
;
2635 * First, we are going to check if there is a new subbuffer available
2636 * before reading the stream wait_fd.
2638 /* Get the next subbuffer */
2639 ret
= ustctl_get_next_subbuf(ustream
);
2641 /* No more data found, flag the stream. */
2642 stream
->has_data
= 0;
2647 ret
= ustctl_put_subbuf(ustream
);
2650 /* This stream still has data. Flag it and wake up the data thread. */
2651 stream
->has_data
= 1;
2653 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !ctx
->has_wakeup
) {
2656 writelen
= lttng_pipe_write(ctx
->consumer_wakeup_pipe
, "!", 1);
2657 if (writelen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2662 /* The wake up pipe has been notified. */
2663 ctx
->has_wakeup
= 1;
2671 static int consumer_stream_ust_on_wake_up(struct lttng_consumer_stream
*stream
)
2676 * We can consume the 1 byte written into the wait_fd by
2677 * UST. Don't trigger error if we cannot read this one byte
2678 * (read returns 0), or if the error is EAGAIN or EWOULDBLOCK.
2680 * This is only done when the stream is monitored by a thread,
2681 * before the flush is done after a hangup and if the stream
2682 * is not flagged with data since there might be nothing to
2683 * consume in the wait fd but still have data available
2684 * flagged by the consumer wake up pipe.
2686 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !stream
->has_data
) {
2690 readlen
= lttng_read(stream
->wait_fd
, &dummy
, 1);
2691 if (readlen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2699 static int extract_common_subbuffer_info(struct lttng_consumer_stream
*stream
,
2700 struct stream_subbuffer
*subbuf
)
2704 ret
= ustctl_get_subbuf_size(
2705 stream
->ustream
, &subbuf
->info
.data
.subbuf_size
);
2710 ret
= ustctl_get_padded_subbuf_size(
2711 stream
->ustream
, &subbuf
->info
.data
.padded_subbuf_size
);
2720 static int extract_metadata_subbuffer_info(struct lttng_consumer_stream
*stream
,
2721 struct stream_subbuffer
*subbuf
)
2725 ret
= extract_common_subbuffer_info(stream
, subbuf
);
2730 subbuf
->info
.metadata
.version
= stream
->metadata_version
;
2736 static int extract_data_subbuffer_info(struct lttng_consumer_stream
*stream
,
2737 struct stream_subbuffer
*subbuf
)
2741 ret
= extract_common_subbuffer_info(stream
, subbuf
);
2746 ret
= ustctl_get_packet_size(
2747 stream
->ustream
, &subbuf
->info
.data
.packet_size
);
2749 PERROR("Failed to get sub-buffer packet size");
2753 ret
= ustctl_get_content_size(
2754 stream
->ustream
, &subbuf
->info
.data
.content_size
);
2756 PERROR("Failed to get sub-buffer content size");
2760 ret
= ustctl_get_timestamp_begin(
2761 stream
->ustream
, &subbuf
->info
.data
.timestamp_begin
);
2763 PERROR("Failed to get sub-buffer begin timestamp");
2767 ret
= ustctl_get_timestamp_end(
2768 stream
->ustream
, &subbuf
->info
.data
.timestamp_end
);
2770 PERROR("Failed to get sub-buffer end timestamp");
2774 ret
= ustctl_get_events_discarded(
2775 stream
->ustream
, &subbuf
->info
.data
.events_discarded
);
2777 PERROR("Failed to get sub-buffer events discarded count");
2781 ret
= ustctl_get_sequence_number(stream
->ustream
,
2782 &subbuf
->info
.data
.sequence_number
.value
);
2784 /* May not be supported by older LTTng-modules. */
2785 if (ret
!= -ENOTTY
) {
2786 PERROR("Failed to get sub-buffer sequence number");
2790 subbuf
->info
.data
.sequence_number
.is_set
= true;
2793 ret
= ustctl_get_stream_id(
2794 stream
->ustream
, &subbuf
->info
.data
.stream_id
);
2796 PERROR("Failed to get stream id");
2800 ret
= ustctl_get_instance_id(stream
->ustream
,
2801 &subbuf
->info
.data
.stream_instance_id
.value
);
2803 /* May not be supported by older LTTng-modules. */
2804 if (ret
!= -ENOTTY
) {
2805 PERROR("Failed to get stream instance id");
2809 subbuf
->info
.data
.stream_instance_id
.is_set
= true;
2815 static int get_next_subbuffer_common(struct lttng_consumer_stream
*stream
,
2816 struct stream_subbuffer
*subbuffer
)
2821 ret
= stream
->read_subbuffer_ops
.extract_subbuffer_info(
2827 ret
= get_current_subbuf_addr(stream
, &addr
);
2832 subbuffer
->buffer
.buffer
= lttng_buffer_view_init(
2833 addr
, 0, subbuffer
->info
.data
.padded_subbuf_size
);
2834 assert(subbuffer
->buffer
.buffer
.data
!= NULL
);
2839 static int get_next_subbuffer(struct lttng_consumer_stream
*stream
,
2840 struct stream_subbuffer
*subbuffer
)
2844 ret
= ustctl_get_next_subbuf(stream
->ustream
);
2849 ret
= get_next_subbuffer_common(stream
, subbuffer
);
2857 static int get_next_subbuffer_metadata(struct lttng_consumer_stream
*stream
,
2858 struct stream_subbuffer
*subbuffer
)
2865 unsigned long consumed_pos
, produced_pos
;
2868 ret
= ustctl_get_next_subbuf(stream
->ustream
);
2870 got_subbuffer
= true;
2872 got_subbuffer
= false;
2873 if (ret
!= -EAGAIN
) {
2880 * Determine if the cache is empty and ensure that a sub-buffer
2881 * is made available if the cache is not empty.
2883 if (!got_subbuffer
) {
2884 ret
= commit_one_metadata_packet(stream
);
2885 if (ret
< 0 && ret
!= -ENOBUFS
) {
2887 } else if (ret
== 0) {
2888 /* Not an error, the cache is empty. */
2893 cache_empty
= false;
2896 pthread_mutex_lock(&stream
->chan
->metadata_cache
->lock
);
2897 cache_empty
= stream
->chan
->metadata_cache
->max_offset
==
2898 stream
->ust_metadata_pushed
;
2899 pthread_mutex_unlock(&stream
->chan
->metadata_cache
->lock
);
2901 } while (!got_subbuffer
);
2903 /* Populate sub-buffer infos and view. */
2904 ret
= get_next_subbuffer_common(stream
, subbuffer
);
2909 ret
= lttng_ustconsumer_sample_snapshot_positions(stream
);
2912 * -EAGAIN is not expected since we got a sub-buffer and haven't
2913 * pushed the consumption position yet (on put_next).
2915 PERROR("Failed to take a snapshot of metadata buffer positions");
2919 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
2921 PERROR("Failed to get metadata consumed position");
2925 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
2927 PERROR("Failed to get metadata produced position");
2931 /* Last sub-buffer of the ring buffer ? */
2932 buffer_empty
= (consumed_pos
+ stream
->max_sb_size
) == produced_pos
;
2935 * The sessiond registry lock ensures that coherent units of metadata
2936 * are pushed to the consumer daemon at once. Hence, if a sub-buffer is
2937 * acquired, the cache is empty, and it is the only available sub-buffer
2938 * available, it is safe to assume that it is "coherent".
2940 coherent
= got_subbuffer
&& cache_empty
&& buffer_empty
;
2942 LTTNG_OPTIONAL_SET(&subbuffer
->info
.metadata
.coherent
, coherent
);
2947 static int put_next_subbuffer(struct lttng_consumer_stream
*stream
,
2948 struct stream_subbuffer
*subbuffer
)
2950 const int ret
= ustctl_put_next_subbuf(stream
->ustream
);
2956 static int signal_metadata(struct lttng_consumer_stream
*stream
,
2957 struct lttng_consumer_local_data
*ctx
)
2959 return pthread_cond_broadcast(&stream
->metadata_rdv
) ? -errno
: 0;
2962 static int lttng_ustconsumer_set_stream_ops(
2963 struct lttng_consumer_stream
*stream
)
2967 stream
->read_subbuffer_ops
.on_wake_up
= consumer_stream_ust_on_wake_up
;
2968 if (stream
->metadata_flag
) {
2969 stream
->read_subbuffer_ops
.get_next_subbuffer
=
2970 get_next_subbuffer_metadata
;
2971 stream
->read_subbuffer_ops
.extract_subbuffer_info
=
2972 extract_metadata_subbuffer_info
;
2973 stream
->read_subbuffer_ops
.reset_metadata
=
2974 metadata_stream_reset_cache_consumed_position
;
2975 if (stream
->chan
->is_live
) {
2976 stream
->read_subbuffer_ops
.on_sleep
= signal_metadata
;
2977 ret
= consumer_stream_enable_metadata_bucketization(
2984 stream
->read_subbuffer_ops
.get_next_subbuffer
=
2986 stream
->read_subbuffer_ops
.extract_subbuffer_info
=
2987 extract_data_subbuffer_info
;
2988 stream
->read_subbuffer_ops
.on_sleep
= notify_if_more_data
;
2989 if (stream
->chan
->is_live
) {
2990 stream
->read_subbuffer_ops
.send_live_beacon
=
2991 consumer_flush_ust_index
;
2995 stream
->read_subbuffer_ops
.put_next_subbuffer
= put_next_subbuffer
;
3001 * Called when a stream is created.
3003 * Return 0 on success or else a negative value.
3005 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
3012 * Don't create anything if this is set for streaming or if there is
3013 * no current trace chunk on the parent channel.
3015 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
&&
3016 stream
->chan
->trace_chunk
) {
3017 ret
= consumer_stream_create_output_files(stream
, true);
3023 lttng_ustconsumer_set_stream_ops(stream
);
3031 * Check if data is still being extracted from the buffers for a specific
3032 * stream. Consumer data lock MUST be acquired before calling this function
3033 * and the stream lock.
3035 * Return 1 if the traced data are still getting read else 0 meaning that the
3036 * data is available for trace viewer reading.
3038 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
3043 assert(stream
->ustream
);
3045 DBG("UST consumer checking data pending");
3047 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
3052 if (stream
->chan
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
3053 uint64_t contiguous
, pushed
;
3055 /* Ease our life a bit. */
3056 pthread_mutex_lock(&stream
->chan
->metadata_cache
->lock
);
3057 contiguous
= stream
->chan
->metadata_cache
->max_offset
;
3058 pthread_mutex_unlock(&stream
->chan
->metadata_cache
->lock
);
3059 pushed
= stream
->ust_metadata_pushed
;
3062 * We can simply check whether all contiguously available data
3063 * has been pushed to the ring buffer, since the push operation
3064 * is performed within get_next_subbuf(), and because both
3065 * get_next_subbuf() and put_next_subbuf() are issued atomically
3066 * thanks to the stream lock within
3067 * lttng_ustconsumer_read_subbuffer(). This basically means that
3068 * whetnever ust_metadata_pushed is incremented, the associated
3069 * metadata has been consumed from the metadata stream.
3071 DBG("UST consumer metadata pending check: contiguous %" PRIu64
" vs pushed %" PRIu64
,
3072 contiguous
, pushed
);
3073 assert(((int64_t) (contiguous
- pushed
)) >= 0);
3074 if ((contiguous
!= pushed
) ||
3075 (((int64_t) contiguous
- pushed
) > 0 || contiguous
== 0)) {
3076 ret
= 1; /* Data is pending */
3080 ret
= ustctl_get_next_subbuf(stream
->ustream
);
3083 * There is still data so let's put back this
3086 ret
= ustctl_put_subbuf(stream
->ustream
);
3088 ret
= 1; /* Data is pending */
3093 /* Data is NOT pending so ready to be read. */
3101 * Stop a given metadata channel timer if enabled and close the wait fd which
3102 * is the poll pipe of the metadata stream.
3104 * This MUST be called with the metadata channel lock acquired.
3106 void lttng_ustconsumer_close_metadata(struct lttng_consumer_channel
*metadata
)
3111 assert(metadata
->type
== CONSUMER_CHANNEL_TYPE_METADATA
);
3113 DBG("Closing metadata channel key %" PRIu64
, metadata
->key
);
3115 if (metadata
->switch_timer_enabled
== 1) {
3116 consumer_timer_switch_stop(metadata
);
3119 if (!metadata
->metadata_stream
) {
3124 * Closing write side so the thread monitoring the stream wakes up if any
3125 * and clean the metadata stream.
3127 if (metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] >= 0) {
3128 ret
= close(metadata
->metadata_stream
->ust_metadata_poll_pipe
[1]);
3130 PERROR("closing metadata pipe write side");
3132 metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] = -1;
3140 * Close every metadata stream wait fd of the metadata hash table. This
3141 * function MUST be used very carefully so not to run into a race between the
3142 * metadata thread handling streams and this function closing their wait fd.
3144 * For UST, this is used when the session daemon hangs up. Its the metadata
3145 * producer so calling this is safe because we are assured that no state change
3146 * can occur in the metadata thread for the streams in the hash table.
3148 void lttng_ustconsumer_close_all_metadata(struct lttng_ht
*metadata_ht
)
3150 struct lttng_ht_iter iter
;
3151 struct lttng_consumer_stream
*stream
;
3153 assert(metadata_ht
);
3154 assert(metadata_ht
->ht
);
3156 DBG("UST consumer closing all metadata streams");
3159 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
3162 health_code_update();
3164 pthread_mutex_lock(&stream
->chan
->lock
);
3165 lttng_ustconsumer_close_metadata(stream
->chan
);
3166 pthread_mutex_unlock(&stream
->chan
->lock
);
3172 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
3176 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
3178 ERR("Unable to close wakeup fd");
3183 * Please refer to consumer-timer.c before adding any lock within this
3184 * function or any of its callees. Timers have a very strict locking
3185 * semantic with respect to teardown. Failure to respect this semantic
3186 * introduces deadlocks.
3188 * DON'T hold the metadata lock when calling this function, else this
3189 * can cause deadlock involving consumer awaiting for metadata to be
3190 * pushed out due to concurrent interaction with the session daemon.
3192 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
3193 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
3195 struct lttcomm_metadata_request_msg request
;
3196 struct lttcomm_consumer_msg msg
;
3197 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
3198 uint64_t len
, key
, offset
, version
;
3202 assert(channel
->metadata_cache
);
3204 memset(&request
, 0, sizeof(request
));
3206 /* send the metadata request to sessiond */
3207 switch (consumer_data
.type
) {
3208 case LTTNG_CONSUMER64_UST
:
3209 request
.bits_per_long
= 64;
3211 case LTTNG_CONSUMER32_UST
:
3212 request
.bits_per_long
= 32;
3215 request
.bits_per_long
= 0;
3219 request
.session_id
= channel
->session_id
;
3220 request
.session_id_per_pid
= channel
->session_id_per_pid
;
3222 * Request the application UID here so the metadata of that application can
3223 * be sent back. The channel UID corresponds to the user UID of the session
3224 * used for the rights on the stream file(s).
3226 request
.uid
= channel
->ust_app_uid
;
3227 request
.key
= channel
->key
;
3229 DBG("Sending metadata request to sessiond, session id %" PRIu64
3230 ", per-pid %" PRIu64
", app UID %u and channel key %" PRIu64
,
3231 request
.session_id
, request
.session_id_per_pid
, request
.uid
,
3234 pthread_mutex_lock(&ctx
->metadata_socket_lock
);
3236 health_code_update();
3238 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
3241 ERR("Asking metadata to sessiond");
3245 health_code_update();
3247 /* Receive the metadata from sessiond */
3248 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
3250 if (ret
!= sizeof(msg
)) {
3251 DBG("Consumer received unexpected message size %d (expects %zu)",
3253 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
3255 * The ret value might 0 meaning an orderly shutdown but this is ok
3256 * since the caller handles this.
3261 health_code_update();
3263 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
3264 /* No registry found */
3265 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
3269 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
3270 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
3275 len
= msg
.u
.push_metadata
.len
;
3276 key
= msg
.u
.push_metadata
.key
;
3277 offset
= msg
.u
.push_metadata
.target_offset
;
3278 version
= msg
.u
.push_metadata
.version
;
3280 assert(key
== channel
->key
);
3282 DBG("No new metadata to receive for key %" PRIu64
, key
);
3285 health_code_update();
3287 /* Tell session daemon we are ready to receive the metadata. */
3288 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
3289 LTTCOMM_CONSUMERD_SUCCESS
);
3290 if (ret
< 0 || len
== 0) {
3292 * Somehow, the session daemon is not responding anymore or there is
3293 * nothing to receive.
3298 health_code_update();
3300 ret
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
3301 key
, offset
, len
, version
, channel
, timer
, wait
);
3304 * Only send the status msg if the sessiond is alive meaning a positive
3307 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret
);
3312 health_code_update();
3314 pthread_mutex_unlock(&ctx
->metadata_socket_lock
);
3319 * Return the ustctl call for the get stream id.
3321 int lttng_ustconsumer_get_stream_id(struct lttng_consumer_stream
*stream
,
3322 uint64_t *stream_id
)
3327 return ustctl_get_stream_id(stream
->ustream
, stream_id
);