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.
22 #include <lttng/ust-ctl.h>
28 #include <sys/socket.h>
30 #include <sys/types.h>
33 #include <urcu/list.h>
36 #include <bin/lttng-consumerd/health-consumerd.h>
37 #include <common/common.h>
38 #include <common/sessiond-comm/sessiond-comm.h>
39 #include <common/relayd/relayd.h>
40 #include <common/compat/fcntl.h>
41 #include <common/compat/endian.h>
42 #include <common/consumer/consumer-metadata-cache.h>
43 #include <common/consumer/consumer-stream.h>
44 #include <common/consumer/consumer-timer.h>
45 #include <common/utils.h>
46 #include <common/index/index.h>
48 #include "ust-consumer.h"
50 #define INT_MAX_STR_LEN 12 /* includes \0 */
52 extern struct lttng_consumer_global_data consumer_data
;
53 extern int consumer_poll_timeout
;
54 extern volatile int consumer_quit
;
57 * Free channel object and all streams associated with it. This MUST be used
58 * only and only if the channel has _NEVER_ been added to the global channel
61 static void destroy_channel(struct lttng_consumer_channel
*channel
)
63 struct lttng_consumer_stream
*stream
, *stmp
;
67 DBG("UST consumer cleaning stream list");
69 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
74 cds_list_del(&stream
->send_node
);
75 ustctl_destroy_stream(stream
->ustream
);
80 * If a channel is available meaning that was created before the streams
84 lttng_ustconsumer_del_channel(channel
);
85 lttng_ustconsumer_free_channel(channel
);
91 * Add channel to internal consumer state.
93 * Returns 0 on success or else a negative value.
95 static int add_channel(struct lttng_consumer_channel
*channel
,
96 struct lttng_consumer_local_data
*ctx
)
103 if (ctx
->on_recv_channel
!= NULL
) {
104 ret
= ctx
->on_recv_channel(channel
);
106 ret
= consumer_add_channel(channel
, ctx
);
107 } else if (ret
< 0) {
108 /* Most likely an ENOMEM. */
109 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
113 ret
= consumer_add_channel(channel
, ctx
);
116 DBG("UST consumer channel added (key: %" PRIu64
")", channel
->key
);
123 * Allocate and return a consumer channel object.
125 static struct lttng_consumer_channel
*allocate_channel(uint64_t session_id
,
126 const char *pathname
, const char *name
, uid_t uid
, gid_t gid
,
127 uint64_t relayd_id
, uint64_t key
, enum lttng_event_output output
,
128 uint64_t tracefile_size
, uint64_t tracefile_count
,
129 uint64_t session_id_per_pid
, unsigned int monitor
,
130 unsigned int live_timer_interval
,
131 const char *root_shm_path
, const char *shm_path
)
136 return consumer_allocate_channel(key
, session_id
, pathname
, name
, uid
,
137 gid
, relayd_id
, output
, tracefile_size
,
138 tracefile_count
, session_id_per_pid
, monitor
,
139 live_timer_interval
, root_shm_path
, shm_path
);
143 * Allocate and return a consumer stream object. If _alloc_ret is not NULL, the
144 * error value if applicable is set in it else it is kept untouched.
146 * Return NULL on error else the newly allocated stream object.
148 static struct lttng_consumer_stream
*allocate_stream(int cpu
, int key
,
149 struct lttng_consumer_channel
*channel
,
150 struct lttng_consumer_local_data
*ctx
, int *_alloc_ret
)
153 struct lttng_consumer_stream
*stream
= NULL
;
158 stream
= consumer_allocate_stream(channel
->key
,
160 LTTNG_CONSUMER_ACTIVE_STREAM
,
170 if (stream
== NULL
) {
174 * We could not find the channel. Can happen if cpu hotplug
175 * happens while tearing down.
177 DBG3("Could not find channel");
182 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
188 stream
->chan
= channel
;
192 *_alloc_ret
= alloc_ret
;
198 * Send the given stream pointer to the corresponding thread.
200 * Returns 0 on success else a negative value.
202 static int send_stream_to_thread(struct lttng_consumer_stream
*stream
,
203 struct lttng_consumer_local_data
*ctx
)
206 struct lttng_pipe
*stream_pipe
;
208 /* Get the right pipe where the stream will be sent. */
209 if (stream
->metadata_flag
) {
210 ret
= consumer_add_metadata_stream(stream
);
212 ERR("Consumer add metadata stream %" PRIu64
" failed.",
216 stream_pipe
= ctx
->consumer_metadata_pipe
;
218 ret
= consumer_add_data_stream(stream
);
220 ERR("Consumer add stream %" PRIu64
" failed.",
224 stream_pipe
= ctx
->consumer_data_pipe
;
228 * From this point on, the stream's ownership has been moved away from
229 * the channel and becomes globally visible.
231 stream
->globally_visible
= 1;
233 ret
= lttng_pipe_write(stream_pipe
, &stream
, sizeof(stream
));
235 ERR("Consumer write %s stream to pipe %d",
236 stream
->metadata_flag
? "metadata" : "data",
237 lttng_pipe_get_writefd(stream_pipe
));
238 if (stream
->metadata_flag
) {
239 consumer_del_stream_for_metadata(stream
);
241 consumer_del_stream_for_data(stream
);
249 int get_stream_shm_path(char *stream_shm_path
, const char *shm_path
, int cpu
)
251 char cpu_nr
[INT_MAX_STR_LEN
]; /* int max len */
254 strncpy(stream_shm_path
, shm_path
, PATH_MAX
);
255 stream_shm_path
[PATH_MAX
- 1] = '\0';
256 ret
= snprintf(cpu_nr
, INT_MAX_STR_LEN
, "%i", cpu
);
261 strncat(stream_shm_path
, cpu_nr
,
262 PATH_MAX
- strlen(stream_shm_path
) - 1);
269 * Create streams for the given channel using liblttng-ust-ctl.
271 * Return 0 on success else a negative value.
273 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
274 struct lttng_consumer_local_data
*ctx
)
277 struct ustctl_consumer_stream
*ustream
;
278 struct lttng_consumer_stream
*stream
;
284 * While a stream is available from ustctl. When NULL is returned, we've
285 * reached the end of the possible stream for the channel.
287 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
289 int ust_metadata_pipe
[2];
291 health_code_update();
293 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& channel
->monitor
) {
294 ret
= utils_create_pipe_cloexec_nonblock(ust_metadata_pipe
);
296 ERR("Create ust metadata poll pipe");
299 wait_fd
= ust_metadata_pipe
[0];
301 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
304 /* Allocate consumer stream object. */
305 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
309 stream
->ustream
= ustream
;
311 * Store it so we can save multiple function calls afterwards since
312 * this value is used heavily in the stream threads. This is UST
313 * specific so this is why it's done after allocation.
315 stream
->wait_fd
= wait_fd
;
318 * Increment channel refcount since the channel reference has now been
319 * assigned in the allocation process above.
321 if (stream
->chan
->monitor
) {
322 uatomic_inc(&stream
->chan
->refcount
);
326 * Order is important this is why a list is used. On error, the caller
327 * should clean this list.
329 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
331 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
332 &stream
->max_sb_size
);
334 ERR("ustctl_get_max_subbuf_size failed for stream %s",
339 /* Do actions once stream has been received. */
340 if (ctx
->on_recv_stream
) {
341 ret
= ctx
->on_recv_stream(stream
);
347 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
348 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
350 /* Set next CPU stream. */
351 channel
->streams
.count
= ++cpu
;
353 /* Keep stream reference when creating metadata. */
354 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
355 channel
->metadata_stream
= stream
;
356 if (channel
->monitor
) {
357 /* Set metadata poll pipe if we created one */
358 memcpy(stream
->ust_metadata_poll_pipe
,
360 sizeof(ust_metadata_pipe
));
373 * create_posix_shm is never called concurrently within a process.
376 int create_posix_shm(void)
378 char tmp_name
[NAME_MAX
];
381 ret
= snprintf(tmp_name
, NAME_MAX
, "/ust-shm-consumer-%d", getpid());
387 * Allocate shm, and immediately unlink its shm oject, keeping
388 * only the file descriptor as a reference to the object.
389 * We specifically do _not_ use the / at the beginning of the
390 * pathname so that some OS implementations can keep it local to
391 * the process (POSIX leaves this implementation-defined).
393 shmfd
= shm_open(tmp_name
, O_CREAT
| O_EXCL
| O_RDWR
, 0700);
398 ret
= shm_unlink(tmp_name
);
399 if (ret
< 0 && errno
!= ENOENT
) {
400 PERROR("shm_unlink");
401 goto error_shm_release
;
414 static int open_ust_stream_fd(struct lttng_consumer_channel
*channel
,
415 struct ustctl_consumer_channel_attr
*attr
,
418 char shm_path
[PATH_MAX
];
421 if (!channel
->shm_path
[0]) {
422 return create_posix_shm();
424 ret
= get_stream_shm_path(shm_path
, channel
->shm_path
, cpu
);
428 return run_as_open(shm_path
,
429 O_RDWR
| O_CREAT
| O_EXCL
, S_IRUSR
| S_IWUSR
,
430 channel
->uid
, channel
->gid
);
437 * Create an UST channel with the given attributes and send it to the session
438 * daemon using the ust ctl API.
440 * Return 0 on success or else a negative value.
442 static int create_ust_channel(struct lttng_consumer_channel
*channel
,
443 struct ustctl_consumer_channel_attr
*attr
,
444 struct ustctl_consumer_channel
**ust_chanp
)
446 int ret
, nr_stream_fds
, i
, j
;
448 struct ustctl_consumer_channel
*ust_channel
;
454 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
455 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
456 "switch_timer_interval: %u, read_timer_interval: %u, "
457 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
458 attr
->num_subbuf
, attr
->switch_timer_interval
,
459 attr
->read_timer_interval
, attr
->output
, attr
->type
);
461 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
)
464 nr_stream_fds
= ustctl_get_nr_stream_per_channel();
465 stream_fds
= zmalloc(nr_stream_fds
* sizeof(*stream_fds
));
470 for (i
= 0; i
< nr_stream_fds
; i
++) {
471 stream_fds
[i
] = open_ust_stream_fd(channel
, attr
, i
);
472 if (stream_fds
[i
] < 0) {
477 ust_channel
= ustctl_create_channel(attr
, stream_fds
, nr_stream_fds
);
482 channel
->nr_stream_fds
= nr_stream_fds
;
483 channel
->stream_fds
= stream_fds
;
484 *ust_chanp
= ust_channel
;
490 for (j
= i
- 1; j
>= 0; j
--) {
493 closeret
= close(stream_fds
[j
]);
497 if (channel
->shm_path
[0]) {
498 char shm_path
[PATH_MAX
];
500 closeret
= get_stream_shm_path(shm_path
,
501 channel
->shm_path
, j
);
503 ERR("Cannot get stream shm path");
505 closeret
= run_as_unlink(shm_path
,
506 channel
->uid
, channel
->gid
);
508 PERROR("unlink %s", shm_path
);
512 /* Try to rmdir all directories under shm_path root. */
513 if (channel
->root_shm_path
[0]) {
514 (void) run_as_recursive_rmdir(channel
->root_shm_path
,
515 channel
->uid
, channel
->gid
);
523 * Send a single given stream to the session daemon using the sock.
525 * Return 0 on success else a negative value.
527 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
534 DBG("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
536 /* Send stream to session daemon. */
537 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
547 * Send channel to sessiond.
549 * Return 0 on success or else a negative value.
551 static int send_sessiond_channel(int sock
,
552 struct lttng_consumer_channel
*channel
,
553 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
555 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
556 struct lttng_consumer_stream
*stream
;
557 uint64_t relayd_id
= -1ULL;
563 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
565 if (channel
->relayd_id
!= (uint64_t) -1ULL) {
566 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
568 health_code_update();
570 /* Try to send the stream to the relayd if one is available. */
571 ret
= consumer_send_relayd_stream(stream
, stream
->chan
->pathname
);
574 * Flag that the relayd was the problem here probably due to a
575 * communicaton error on the socket.
580 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
582 if (relayd_id
== -1ULL) {
583 relayd_id
= stream
->relayd_id
;
588 /* Inform sessiond that we are about to send channel and streams. */
589 ret
= consumer_send_status_msg(sock
, ret_code
);
590 if (ret
< 0 || ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
592 * Either the session daemon is not responding or the relayd died so we
598 /* Send channel to sessiond. */
599 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
604 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
609 /* The channel was sent successfully to the sessiond at this point. */
610 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
612 health_code_update();
614 /* Send stream to session daemon. */
615 ret
= send_sessiond_stream(sock
, stream
);
621 /* Tell sessiond there is no more stream. */
622 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
627 DBG("UST consumer NULL stream sent to sessiond");
632 if (ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
639 * Creates a channel and streams and add the channel it to the channel internal
640 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
643 * Return 0 on success or else, a negative value is returned and the channel
644 * MUST be destroyed by consumer_del_channel().
646 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
647 struct lttng_consumer_channel
*channel
,
648 struct ustctl_consumer_channel_attr
*attr
)
657 * This value is still used by the kernel consumer since for the kernel,
658 * the stream ownership is not IN the consumer so we need to have the
659 * number of left stream that needs to be initialized so we can know when
660 * to delete the channel (see consumer.c).
662 * As for the user space tracer now, the consumer creates and sends the
663 * stream to the session daemon which only sends them to the application
664 * once every stream of a channel is received making this value useless
665 * because we they will be added to the poll thread before the application
666 * receives them. This ensures that a stream can not hang up during
667 * initilization of a channel.
669 channel
->nb_init_stream_left
= 0;
671 /* The reply msg status is handled in the following call. */
672 ret
= create_ust_channel(channel
, attr
, &channel
->uchan
);
677 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
680 * For the snapshots (no monitor), we create the metadata streams
681 * on demand, not during the channel creation.
683 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& !channel
->monitor
) {
688 /* Open all streams for this channel. */
689 ret
= create_ust_streams(channel
, ctx
);
699 * Send all stream of a channel to the right thread handling it.
701 * On error, return a negative value else 0 on success.
703 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
704 struct lttng_consumer_local_data
*ctx
)
707 struct lttng_consumer_stream
*stream
, *stmp
;
712 /* Send streams to the corresponding thread. */
713 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
716 health_code_update();
718 /* Sending the stream to the thread. */
719 ret
= send_stream_to_thread(stream
, ctx
);
722 * If we are unable to send the stream to the thread, there is
723 * a big problem so just stop everything.
725 /* Remove node from the channel stream list. */
726 cds_list_del(&stream
->send_node
);
730 /* Remove node from the channel stream list. */
731 cds_list_del(&stream
->send_node
);
740 * Flush channel's streams using the given key to retrieve the channel.
742 * Return 0 on success else an LTTng error code.
744 static int flush_channel(uint64_t chan_key
)
747 struct lttng_consumer_channel
*channel
;
748 struct lttng_consumer_stream
*stream
;
750 struct lttng_ht_iter iter
;
752 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
755 channel
= consumer_find_channel(chan_key
);
757 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
758 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
762 ht
= consumer_data
.stream_per_chan_id_ht
;
764 /* For each stream of the channel id, flush it. */
765 cds_lfht_for_each_entry_duplicate(ht
->ht
,
766 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
767 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
769 health_code_update();
771 pthread_mutex_lock(&stream
->lock
);
774 * Protect against concurrent teardown of a stream.
776 if (cds_lfht_is_node_deleted(&stream
->node
.node
)) {
780 if (!stream
->quiescent
) {
781 ustctl_flush_buffer(stream
->ustream
, 0);
782 stream
->quiescent
= true;
785 pthread_mutex_unlock(&stream
->lock
);
793 * Clear quiescent state from channel's streams using the given key to
794 * retrieve the channel.
796 * Return 0 on success else an LTTng error code.
798 static int clear_quiescent_channel(uint64_t chan_key
)
801 struct lttng_consumer_channel
*channel
;
802 struct lttng_consumer_stream
*stream
;
804 struct lttng_ht_iter iter
;
806 DBG("UST consumer clear quiescent channel key %" PRIu64
, chan_key
);
809 channel
= consumer_find_channel(chan_key
);
811 ERR("UST consumer clear quiescent channel %" PRIu64
" not found", chan_key
);
812 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
816 ht
= consumer_data
.stream_per_chan_id_ht
;
818 /* For each stream of the channel id, clear quiescent state. */
819 cds_lfht_for_each_entry_duplicate(ht
->ht
,
820 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
821 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
823 health_code_update();
825 pthread_mutex_lock(&stream
->lock
);
826 stream
->quiescent
= false;
827 pthread_mutex_unlock(&stream
->lock
);
835 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
836 * RCU read side lock MUST be acquired before calling this function.
838 * Return 0 on success else an LTTng error code.
840 static int close_metadata(uint64_t chan_key
)
843 struct lttng_consumer_channel
*channel
;
844 unsigned int channel_monitor
;
846 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
848 channel
= consumer_find_channel(chan_key
);
851 * This is possible if the metadata thread has issue a delete because
852 * the endpoint point of the stream hung up. There is no way the
853 * session daemon can know about it thus use a DBG instead of an actual
856 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
857 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
861 pthread_mutex_lock(&consumer_data
.lock
);
862 pthread_mutex_lock(&channel
->lock
);
863 channel_monitor
= channel
->monitor
;
864 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
868 lttng_ustconsumer_close_metadata(channel
);
869 pthread_mutex_unlock(&channel
->lock
);
870 pthread_mutex_unlock(&consumer_data
.lock
);
873 * The ownership of a metadata channel depends on the type of
874 * session to which it belongs. In effect, the monitor flag is checked
875 * to determine if this metadata channel is in "snapshot" mode or not.
877 * In the non-snapshot case, the metadata channel is created along with
878 * a single stream which will remain present until the metadata channel
879 * is destroyed (on the destruction of its session). In this case, the
880 * metadata stream in "monitored" by the metadata poll thread and holds
881 * the ownership of its channel.
883 * Closing the metadata will cause the metadata stream's "metadata poll
884 * pipe" to be closed. Closing this pipe will wake-up the metadata poll
885 * thread which will teardown the metadata stream which, in return,
886 * deletes the metadata channel.
888 * In the snapshot case, the metadata stream is created and destroyed
889 * on every snapshot record. Since the channel doesn't have an owner
890 * other than the session daemon, it is safe to destroy it immediately
891 * on reception of the CLOSE_METADATA command.
893 if (!channel_monitor
) {
895 * The channel and consumer_data locks must be
896 * released before this call since consumer_del_channel
897 * re-acquires the channel and consumer_data locks to teardown
898 * the channel and queue its reclamation by the "call_rcu"
901 consumer_del_channel(channel
);
906 pthread_mutex_unlock(&channel
->lock
);
907 pthread_mutex_unlock(&consumer_data
.lock
);
913 * RCU read side lock MUST be acquired before calling this function.
915 * Return 0 on success else an LTTng error code.
917 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
920 struct lttng_consumer_channel
*metadata
;
922 DBG("UST consumer setup metadata key %" PRIu64
, key
);
924 metadata
= consumer_find_channel(key
);
926 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
927 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
932 * In no monitor mode, the metadata channel has no stream(s) so skip the
933 * ownership transfer to the metadata thread.
935 if (!metadata
->monitor
) {
936 DBG("Metadata channel in no monitor");
942 * Send metadata stream to relayd if one available. Availability is
943 * known if the stream is still in the list of the channel.
945 if (cds_list_empty(&metadata
->streams
.head
)) {
946 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
947 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
948 goto error_no_stream
;
951 /* Send metadata stream to relayd if needed. */
952 if (metadata
->metadata_stream
->relayd_id
!= (uint64_t) -1ULL) {
953 ret
= consumer_send_relayd_stream(metadata
->metadata_stream
,
956 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
959 ret
= consumer_send_relayd_streams_sent(
960 metadata
->metadata_stream
->relayd_id
);
962 ret
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
967 ret
= send_streams_to_thread(metadata
, ctx
);
970 * If we are unable to send the stream to the thread, there is
971 * a big problem so just stop everything.
973 ret
= LTTCOMM_CONSUMERD_FATAL
;
976 /* List MUST be empty after or else it could be reused. */
977 assert(cds_list_empty(&metadata
->streams
.head
));
984 * Delete metadata channel on error. At this point, the metadata stream can
985 * NOT be monitored by the metadata thread thus having the guarantee that
986 * the stream is still in the local stream list of the channel. This call
987 * will make sure to clean that list.
989 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
990 cds_list_del(&metadata
->metadata_stream
->send_node
);
991 metadata
->metadata_stream
= NULL
;
998 * Snapshot the whole metadata.
1000 * Returns 0 on success, < 0 on error
1002 static int snapshot_metadata(uint64_t key
, char *path
, uint64_t relayd_id
,
1003 struct lttng_consumer_local_data
*ctx
)
1006 struct lttng_consumer_channel
*metadata_channel
;
1007 struct lttng_consumer_stream
*metadata_stream
;
1012 DBG("UST consumer snapshot metadata with key %" PRIu64
" at path %s",
1017 metadata_channel
= consumer_find_channel(key
);
1018 if (!metadata_channel
) {
1019 ERR("UST snapshot metadata channel not found for key %" PRIu64
,
1024 assert(!metadata_channel
->monitor
);
1026 health_code_update();
1029 * Ask the sessiond if we have new metadata waiting and update the
1030 * consumer metadata cache.
1032 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
, 0, 1);
1037 health_code_update();
1040 * The metadata stream is NOT created in no monitor mode when the channel
1041 * is created on a sessiond ask channel command.
1043 ret
= create_ust_streams(metadata_channel
, ctx
);
1048 metadata_stream
= metadata_channel
->metadata_stream
;
1049 assert(metadata_stream
);
1051 if (relayd_id
!= (uint64_t) -1ULL) {
1052 metadata_stream
->relayd_id
= relayd_id
;
1053 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
1058 ret
= utils_create_stream_file(path
, metadata_stream
->name
,
1059 metadata_stream
->chan
->tracefile_size
,
1060 metadata_stream
->tracefile_count_current
,
1061 metadata_stream
->uid
, metadata_stream
->gid
, NULL
);
1065 metadata_stream
->out_fd
= ret
;
1066 metadata_stream
->tracefile_size_current
= 0;
1070 health_code_update();
1072 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
);
1080 * Clean up the stream completly because the next snapshot will use a new
1083 consumer_stream_destroy(metadata_stream
, NULL
);
1084 cds_list_del(&metadata_stream
->send_node
);
1085 metadata_channel
->metadata_stream
= NULL
;
1093 int get_current_subbuf_addr(struct lttng_consumer_stream
*stream
,
1097 unsigned long mmap_offset
;
1098 const char *mmap_base
;
1100 mmap_base
= ustctl_get_mmap_base(stream
->ustream
);
1102 ERR("Failed to get mmap base for stream `%s`",
1108 ret
= ustctl_get_mmap_read_offset(stream
->ustream
, &mmap_offset
);
1110 ERR("Failed to get mmap offset for stream `%s`", stream
->name
);
1115 *addr
= mmap_base
+ mmap_offset
;
1122 * Take a snapshot of all the stream of a channel.
1124 * Returns 0 on success, < 0 on error
1126 static int snapshot_channel(uint64_t key
, char *path
, uint64_t relayd_id
,
1127 uint64_t nb_packets_per_stream
, struct lttng_consumer_local_data
*ctx
)
1130 unsigned use_relayd
= 0;
1131 unsigned long consumed_pos
, produced_pos
;
1132 struct lttng_consumer_channel
*channel
;
1133 struct lttng_consumer_stream
*stream
;
1140 if (relayd_id
!= (uint64_t) -1ULL) {
1144 channel
= consumer_find_channel(key
);
1146 ERR("UST snapshot channel not found for key %" PRIu64
, key
);
1150 assert(!channel
->monitor
);
1151 DBG("UST consumer snapshot channel %" PRIu64
, key
);
1153 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
1154 health_code_update();
1156 /* Lock stream because we are about to change its state. */
1157 pthread_mutex_lock(&stream
->lock
);
1158 stream
->relayd_id
= relayd_id
;
1161 ret
= consumer_send_relayd_stream(stream
, path
);
1166 ret
= utils_create_stream_file(path
, stream
->name
,
1167 stream
->chan
->tracefile_size
,
1168 stream
->tracefile_count_current
,
1169 stream
->uid
, stream
->gid
, NULL
);
1173 stream
->out_fd
= ret
;
1174 stream
->tracefile_size_current
= 0;
1176 DBG("UST consumer snapshot stream %s/%s (%" PRIu64
")", path
,
1177 stream
->name
, stream
->key
);
1179 if (relayd_id
!= -1ULL) {
1180 ret
= consumer_send_relayd_streams_sent(relayd_id
);
1187 * If tracing is active, we want to perform a "full" buffer flush.
1188 * Else, if quiescent, it has already been done by the prior stop.
1190 if (!stream
->quiescent
) {
1191 ustctl_flush_buffer(stream
->ustream
, 0);
1194 ret
= lttng_ustconsumer_take_snapshot(stream
);
1196 ERR("Taking UST snapshot");
1200 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
1202 ERR("Produced UST snapshot position");
1206 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
1208 ERR("Consumerd UST snapshot position");
1213 * The original value is sent back if max stream size is larger than
1214 * the possible size of the snapshot. Also, we assume that the session
1215 * daemon should never send a maximum stream size that is lower than
1218 consumed_pos
= consumer_get_consume_start_pos(consumed_pos
,
1219 produced_pos
, nb_packets_per_stream
,
1220 stream
->max_sb_size
);
1222 while (consumed_pos
< produced_pos
) {
1224 unsigned long len
, padded_len
;
1225 const char *subbuf_addr
;
1226 struct lttng_buffer_view subbuf_view
;
1228 health_code_update();
1230 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
1232 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
1234 if (ret
!= -EAGAIN
) {
1235 PERROR("ustctl_get_subbuf snapshot");
1236 goto error_close_stream
;
1238 DBG("UST consumer get subbuf failed. Skipping it.");
1239 consumed_pos
+= stream
->max_sb_size
;
1240 stream
->chan
->lost_packets
++;
1244 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
1246 ERR("Snapshot ustctl_get_subbuf_size");
1247 goto error_put_subbuf
;
1250 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
1252 ERR("Snapshot ustctl_get_padded_subbuf_size");
1253 goto error_put_subbuf
;
1256 ret
= get_current_subbuf_addr(stream
, &subbuf_addr
);
1258 goto error_put_subbuf
;
1261 subbuf_view
= lttng_buffer_view_init(
1262 subbuf_addr
, 0, padded_len
);
1263 read_len
= lttng_consumer_on_read_subbuffer_mmap(ctx
,
1264 stream
, &subbuf_view
, padded_len
- len
,
1267 if (read_len
!= len
) {
1269 goto error_put_subbuf
;
1272 if (read_len
!= padded_len
) {
1274 goto error_put_subbuf
;
1278 ret
= ustctl_put_subbuf(stream
->ustream
);
1280 ERR("Snapshot ustctl_put_subbuf");
1281 goto error_close_stream
;
1283 consumed_pos
+= stream
->max_sb_size
;
1286 /* Simply close the stream so we can use it on the next snapshot. */
1287 consumer_stream_close(stream
);
1288 pthread_mutex_unlock(&stream
->lock
);
1295 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
1296 ERR("Snapshot ustctl_put_subbuf");
1299 consumer_stream_close(stream
);
1301 pthread_mutex_unlock(&stream
->lock
);
1308 * Receive the metadata updates from the sessiond. Supports receiving
1309 * overlapping metadata, but is needs to always belong to a contiguous
1310 * range starting from 0.
1311 * Be careful about the locks held when calling this function: it needs
1312 * the metadata cache flush to concurrently progress in order to
1315 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
1316 uint64_t len
, uint64_t version
,
1317 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
1319 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1322 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
1324 metadata_str
= zmalloc(len
* sizeof(char));
1325 if (!metadata_str
) {
1326 PERROR("zmalloc metadata string");
1327 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
1331 health_code_update();
1333 /* Receive metadata string. */
1334 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1336 /* Session daemon is dead so return gracefully. */
1341 health_code_update();
1343 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1344 ret
= consumer_metadata_cache_write(channel
, offset
, len
, version
,
1347 /* Unable to handle metadata. Notify session daemon. */
1348 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1350 * Skip metadata flush on write error since the offset and len might
1351 * not have been updated which could create an infinite loop below when
1352 * waiting for the metadata cache to be flushed.
1354 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1357 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1362 while (consumer_metadata_cache_flushed(channel
, offset
+ len
, timer
)) {
1363 DBG("Waiting for metadata to be flushed");
1365 health_code_update();
1367 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1377 * Receive command from session daemon and process it.
1379 * Return 1 on success else a negative value or 0.
1381 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1382 int sock
, struct pollfd
*consumer_sockpoll
)
1385 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1386 struct lttcomm_consumer_msg msg
;
1387 struct lttng_consumer_channel
*channel
= NULL
;
1389 health_code_update();
1391 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1392 if (ret
!= sizeof(msg
)) {
1393 DBG("Consumer received unexpected message size %zd (expects %zu)",
1396 * The ret value might 0 meaning an orderly shutdown but this is ok
1397 * since the caller handles this.
1400 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1406 health_code_update();
1409 assert(msg
.cmd_type
!= LTTNG_CONSUMER_STOP
);
1411 health_code_update();
1413 /* relayd needs RCU read-side lock */
1416 switch (msg
.cmd_type
) {
1417 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1419 /* Session daemon status message are handled in the following call. */
1420 consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1421 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1422 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
,
1423 msg
.u
.relayd_sock
.relayd_session_id
);
1426 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1428 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1429 struct consumer_relayd_sock_pair
*relayd
;
1431 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1433 /* Get relayd reference if exists. */
1434 relayd
= consumer_find_relayd(index
);
1435 if (relayd
== NULL
) {
1436 DBG("Unable to find relayd %" PRIu64
, index
);
1437 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
1441 * Each relayd socket pair has a refcount of stream attached to it
1442 * which tells if the relayd is still active or not depending on the
1445 * This will set the destroy flag of the relayd object and destroy it
1446 * if the refcount reaches zero when called.
1448 * The destroy can happen either here or when a stream fd hangs up.
1451 consumer_flag_relayd_for_destroy(relayd
);
1454 goto end_msg_sessiond
;
1456 case LTTNG_CONSUMER_UPDATE_STREAM
:
1461 case LTTNG_CONSUMER_DATA_PENDING
:
1463 int ret
, is_data_pending
;
1464 uint64_t id
= msg
.u
.data_pending
.session_id
;
1466 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1468 is_data_pending
= consumer_data_pending(id
);
1470 /* Send back returned value to session daemon */
1471 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1472 sizeof(is_data_pending
));
1474 DBG("Error when sending the data pending ret code: %d", ret
);
1479 * No need to send back a status message since the data pending
1480 * returned value is the response.
1484 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1487 struct ustctl_consumer_channel_attr attr
;
1489 /* Create a plain object and reserve a channel key. */
1490 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
1491 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
1492 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
1493 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
1494 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1495 msg
.u
.ask_channel
.tracefile_size
,
1496 msg
.u
.ask_channel
.tracefile_count
,
1497 msg
.u
.ask_channel
.session_id_per_pid
,
1498 msg
.u
.ask_channel
.monitor
,
1499 msg
.u
.ask_channel
.live_timer_interval
,
1500 msg
.u
.ask_channel
.root_shm_path
,
1501 msg
.u
.ask_channel
.shm_path
);
1503 goto end_channel_error
;
1507 * Assign UST application UID to the channel. This value is ignored for
1508 * per PID buffers. This is specific to UST thus setting this after the
1511 channel
->ust_app_uid
= msg
.u
.ask_channel
.ust_app_uid
;
1513 /* Build channel attributes from received message. */
1514 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1515 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1516 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1517 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1518 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1519 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1520 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1522 /* Match channel buffer type to the UST abi. */
1523 switch (msg
.u
.ask_channel
.output
) {
1524 case LTTNG_EVENT_MMAP
:
1526 attr
.output
= LTTNG_UST_MMAP
;
1530 /* Translate and save channel type. */
1531 switch (msg
.u
.ask_channel
.type
) {
1532 case LTTNG_UST_CHAN_PER_CPU
:
1533 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1534 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1536 * Set refcount to 1 for owner. Below, we will
1537 * pass ownership to the
1538 * consumer_thread_channel_poll() thread.
1540 channel
->refcount
= 1;
1542 case LTTNG_UST_CHAN_METADATA
:
1543 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1544 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1551 health_code_update();
1553 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
1555 goto end_channel_error
;
1558 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1559 ret
= consumer_metadata_cache_allocate(channel
);
1561 ERR("Allocating metadata cache");
1562 goto end_channel_error
;
1564 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1565 attr
.switch_timer_interval
= 0;
1567 consumer_timer_live_start(channel
,
1568 msg
.u
.ask_channel
.live_timer_interval
);
1571 health_code_update();
1574 * Add the channel to the internal state AFTER all streams were created
1575 * and successfully sent to session daemon. This way, all streams must
1576 * be ready before this channel is visible to the threads.
1577 * If add_channel succeeds, ownership of the channel is
1578 * passed to consumer_thread_channel_poll().
1580 ret
= add_channel(channel
, ctx
);
1582 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1583 if (channel
->switch_timer_enabled
== 1) {
1584 consumer_timer_switch_stop(channel
);
1586 consumer_metadata_cache_destroy(channel
);
1588 if (channel
->live_timer_enabled
== 1) {
1589 consumer_timer_live_stop(channel
);
1591 goto end_channel_error
;
1594 health_code_update();
1597 * Channel and streams are now created. Inform the session daemon that
1598 * everything went well and should wait to receive the channel and
1599 * streams with ustctl API.
1601 ret
= consumer_send_status_channel(sock
, channel
);
1604 * There is probably a problem on the socket.
1611 case LTTNG_CONSUMER_GET_CHANNEL
:
1613 int ret
, relayd_err
= 0;
1614 uint64_t key
= msg
.u
.get_channel
.key
;
1615 struct lttng_consumer_channel
*channel
;
1617 channel
= consumer_find_channel(key
);
1619 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1620 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1621 goto end_msg_sessiond
;
1624 health_code_update();
1626 /* Send everything to sessiond. */
1627 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
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.
1639 * The communicaton was broken hence there is a bad state between
1640 * the consumer and sessiond so stop everything.
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_msg_sessiond
;
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.
1663 /* List MUST be empty after or else it could be reused. */
1664 assert(cds_list_empty(&channel
->streams
.head
));
1665 goto end_msg_sessiond
;
1667 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1669 uint64_t key
= msg
.u
.destroy_channel
.key
;
1672 * Only called if streams have not been sent to stream
1673 * manager thread. However, channel has been sent to
1674 * channel manager thread.
1676 notify_thread_del_channel(ctx
, key
);
1677 goto end_msg_sessiond
;
1679 case LTTNG_CONSUMER_CLOSE_METADATA
:
1683 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1688 goto end_msg_sessiond
;
1690 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1694 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1699 goto end_msg_sessiond
;
1701 case LTTNG_CONSUMER_CLEAR_QUIESCENT_CHANNEL
:
1705 ret
= clear_quiescent_channel(
1706 msg
.u
.clear_quiescent_channel
.key
);
1711 goto end_msg_sessiond
;
1713 case LTTNG_CONSUMER_PUSH_METADATA
:
1716 uint64_t len
= msg
.u
.push_metadata
.len
;
1717 uint64_t key
= msg
.u
.push_metadata
.key
;
1718 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1719 uint64_t version
= msg
.u
.push_metadata
.version
;
1720 struct lttng_consumer_channel
*channel
;
1722 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1725 channel
= consumer_find_channel(key
);
1728 * This is possible if the metadata creation on the consumer side
1729 * is in flight vis-a-vis a concurrent push metadata from the
1730 * session daemon. Simply return that the channel failed and the
1731 * session daemon will handle that message correctly considering
1732 * that this race is acceptable thus the DBG() statement here.
1734 DBG("UST consumer push metadata %" PRIu64
" not found", key
);
1735 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1736 goto end_msg_sessiond
;
1739 health_code_update();
1743 * There is nothing to receive. We have simply
1744 * checked whether the channel can be found.
1746 ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1747 goto end_msg_sessiond
;
1750 /* Tell session daemon we are ready to receive the metadata. */
1751 ret
= consumer_send_status_msg(sock
, LTTCOMM_CONSUMERD_SUCCESS
);
1753 /* Somehow, the session daemon is not responding anymore. */
1757 health_code_update();
1759 /* Wait for more data. */
1760 health_poll_entry();
1761 ret
= lttng_consumer_poll_socket(consumer_sockpoll
);
1767 health_code_update();
1769 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1770 len
, version
, channel
, 0, 1);
1772 /* error receiving from sessiond */
1776 goto end_msg_sessiond
;
1779 case LTTNG_CONSUMER_SETUP_METADATA
:
1783 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1787 goto end_msg_sessiond
;
1789 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1791 if (msg
.u
.snapshot_channel
.metadata
) {
1792 ret
= snapshot_metadata(msg
.u
.snapshot_channel
.key
,
1793 msg
.u
.snapshot_channel
.pathname
,
1794 msg
.u
.snapshot_channel
.relayd_id
,
1797 ERR("Snapshot metadata failed");
1798 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1801 ret
= snapshot_channel(msg
.u
.snapshot_channel
.key
,
1802 msg
.u
.snapshot_channel
.pathname
,
1803 msg
.u
.snapshot_channel
.relayd_id
,
1804 msg
.u
.snapshot_channel
.nb_packets_per_stream
,
1807 ERR("Snapshot channel failed");
1808 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1812 health_code_update();
1813 ret
= consumer_send_status_msg(sock
, ret_code
);
1815 /* Somehow, the session daemon is not responding anymore. */
1818 health_code_update();
1821 case LTTNG_CONSUMER_DISCARDED_EVENTS
:
1824 uint64_t discarded_events
;
1825 struct lttng_ht_iter iter
;
1826 struct lttng_ht
*ht
;
1827 struct lttng_consumer_stream
*stream
;
1828 uint64_t id
= msg
.u
.discarded_events
.session_id
;
1829 uint64_t key
= msg
.u
.discarded_events
.channel_key
;
1831 DBG("UST consumer discarded events command for session id %"
1834 pthread_mutex_lock(&consumer_data
.lock
);
1836 ht
= consumer_data
.stream_list_ht
;
1839 * We only need a reference to the channel, but they are not
1840 * directly indexed, so we just use the first matching stream
1841 * to extract the information we need, we default to 0 if not
1842 * found (no events are dropped if the channel is not yet in
1845 discarded_events
= 0;
1846 cds_lfht_for_each_entry_duplicate(ht
->ht
,
1847 ht
->hash_fct(&id
, lttng_ht_seed
),
1849 &iter
.iter
, stream
, node_session_id
.node
) {
1850 if (stream
->chan
->key
== key
) {
1851 discarded_events
= stream
->chan
->discarded_events
;
1855 pthread_mutex_unlock(&consumer_data
.lock
);
1858 DBG("UST consumer discarded events command for session id %"
1859 PRIu64
", channel key %" PRIu64
, id
, key
);
1861 health_code_update();
1863 /* Send back returned value to session daemon */
1864 ret
= lttcomm_send_unix_sock(sock
, &discarded_events
, sizeof(discarded_events
));
1866 PERROR("send discarded events");
1872 case LTTNG_CONSUMER_LOST_PACKETS
:
1875 uint64_t lost_packets
;
1876 struct lttng_ht_iter iter
;
1877 struct lttng_ht
*ht
;
1878 struct lttng_consumer_stream
*stream
;
1879 uint64_t id
= msg
.u
.lost_packets
.session_id
;
1880 uint64_t key
= msg
.u
.lost_packets
.channel_key
;
1882 DBG("UST consumer lost packets command for session id %"
1885 pthread_mutex_lock(&consumer_data
.lock
);
1887 ht
= consumer_data
.stream_list_ht
;
1890 * We only need a reference to the channel, but they are not
1891 * directly indexed, so we just use the first matching stream
1892 * to extract the information we need, we default to 0 if not
1893 * found (no packets lost if the channel is not yet in use).
1896 cds_lfht_for_each_entry_duplicate(ht
->ht
,
1897 ht
->hash_fct(&id
, lttng_ht_seed
),
1899 &iter
.iter
, stream
, node_session_id
.node
) {
1900 if (stream
->chan
->key
== key
) {
1901 lost_packets
= stream
->chan
->lost_packets
;
1905 pthread_mutex_unlock(&consumer_data
.lock
);
1908 DBG("UST consumer lost packets command for session id %"
1909 PRIu64
", channel key %" PRIu64
, id
, key
);
1911 health_code_update();
1913 /* Send back returned value to session daemon */
1914 ret
= lttcomm_send_unix_sock(sock
, &lost_packets
,
1915 sizeof(lost_packets
));
1917 PERROR("send lost packets");
1930 health_code_update();
1933 * Return 1 to indicate success since the 0 value can be a socket
1934 * shutdown during the recv() or send() call.
1940 * The returned value here is not useful since either way we'll return 1 to
1941 * the caller because the session daemon socket management is done
1942 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1944 ret
= consumer_send_status_msg(sock
, ret_code
);
1950 health_code_update();
1956 * Free channel here since no one has a reference to it. We don't
1957 * free after that because a stream can store this pointer.
1959 destroy_channel(channel
);
1961 /* We have to send a status channel message indicating an error. */
1962 ret
= consumer_send_status_channel(sock
, NULL
);
1964 /* Stop everything if session daemon can not be notified. */
1969 health_code_update();
1974 /* This will issue a consumer stop. */
1978 void lttng_ustctl_flush_buffer(struct lttng_consumer_stream
*stream
,
1979 int producer_active
)
1982 assert(stream
->ustream
);
1984 ustctl_flush_buffer(stream
->ustream
, producer_active
);
1988 * Take a snapshot for a specific fd
1990 * Returns 0 on success, < 0 on error
1992 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1995 assert(stream
->ustream
);
1997 return ustctl_snapshot(stream
->ustream
);
2001 * Get the produced position
2003 * Returns 0 on success, < 0 on error
2005 int lttng_ustconsumer_get_produced_snapshot(
2006 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
2009 assert(stream
->ustream
);
2012 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
2016 * Get the consumed position
2018 * Returns 0 on success, < 0 on error
2020 int lttng_ustconsumer_get_consumed_snapshot(
2021 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
2024 assert(stream
->ustream
);
2027 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
2030 void lttng_ustconsumer_flush_buffer(struct lttng_consumer_stream
*stream
,
2034 assert(stream
->ustream
);
2036 ustctl_flush_buffer(stream
->ustream
, producer
);
2039 int lttng_ustconsumer_get_current_timestamp(
2040 struct lttng_consumer_stream
*stream
, uint64_t *ts
)
2043 assert(stream
->ustream
);
2046 return ustctl_get_current_timestamp(stream
->ustream
, ts
);
2049 int lttng_ustconsumer_get_sequence_number(
2050 struct lttng_consumer_stream
*stream
, uint64_t *seq
)
2053 assert(stream
->ustream
);
2056 return ustctl_get_sequence_number(stream
->ustream
, seq
);
2060 * Called when the stream signals the consumer that it has hung up.
2062 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
2065 assert(stream
->ustream
);
2067 pthread_mutex_lock(&stream
->lock
);
2068 if (!stream
->quiescent
) {
2069 ustctl_flush_buffer(stream
->ustream
, 0);
2070 stream
->quiescent
= true;
2072 pthread_mutex_unlock(&stream
->lock
);
2073 stream
->hangup_flush_done
= 1;
2076 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
2081 assert(chan
->uchan
);
2083 if (chan
->switch_timer_enabled
== 1) {
2084 consumer_timer_switch_stop(chan
);
2086 for (i
= 0; i
< chan
->nr_stream_fds
; i
++) {
2089 ret
= close(chan
->stream_fds
[i
]);
2093 if (chan
->shm_path
[0]) {
2094 char shm_path
[PATH_MAX
];
2096 ret
= get_stream_shm_path(shm_path
, chan
->shm_path
, i
);
2098 ERR("Cannot get stream shm path");
2100 ret
= run_as_unlink(shm_path
, chan
->uid
, chan
->gid
);
2102 PERROR("unlink %s", shm_path
);
2108 void lttng_ustconsumer_free_channel(struct lttng_consumer_channel
*chan
)
2111 assert(chan
->uchan
);
2113 consumer_metadata_cache_destroy(chan
);
2114 ustctl_destroy_channel(chan
->uchan
);
2115 /* Try to rmdir all directories under shm_path root. */
2116 if (chan
->root_shm_path
[0]) {
2117 (void) run_as_recursive_rmdir(chan
->root_shm_path
,
2118 chan
->uid
, chan
->gid
);
2120 free(chan
->stream_fds
);
2123 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
2126 assert(stream
->ustream
);
2128 if (stream
->chan
->switch_timer_enabled
== 1) {
2129 consumer_timer_switch_stop(stream
->chan
);
2131 ustctl_destroy_stream(stream
->ustream
);
2134 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream
*stream
)
2137 assert(stream
->ustream
);
2139 return ustctl_stream_get_wakeup_fd(stream
->ustream
);
2142 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream
*stream
)
2145 assert(stream
->ustream
);
2147 return ustctl_stream_close_wakeup_fd(stream
->ustream
);
2151 * Populate index values of a UST stream. Values are set in big endian order.
2153 * Return 0 on success or else a negative value.
2155 static int get_index_values(struct ctf_packet_index
*index
,
2156 struct ustctl_consumer_stream
*ustream
)
2160 ret
= ustctl_get_timestamp_begin(ustream
, &index
->timestamp_begin
);
2162 PERROR("ustctl_get_timestamp_begin");
2165 index
->timestamp_begin
= htobe64(index
->timestamp_begin
);
2167 ret
= ustctl_get_timestamp_end(ustream
, &index
->timestamp_end
);
2169 PERROR("ustctl_get_timestamp_end");
2172 index
->timestamp_end
= htobe64(index
->timestamp_end
);
2174 ret
= ustctl_get_events_discarded(ustream
, &index
->events_discarded
);
2176 PERROR("ustctl_get_events_discarded");
2179 index
->events_discarded
= htobe64(index
->events_discarded
);
2181 ret
= ustctl_get_content_size(ustream
, &index
->content_size
);
2183 PERROR("ustctl_get_content_size");
2186 index
->content_size
= htobe64(index
->content_size
);
2188 ret
= ustctl_get_packet_size(ustream
, &index
->packet_size
);
2190 PERROR("ustctl_get_packet_size");
2193 index
->packet_size
= htobe64(index
->packet_size
);
2195 ret
= ustctl_get_stream_id(ustream
, &index
->stream_id
);
2197 PERROR("ustctl_get_stream_id");
2200 index
->stream_id
= htobe64(index
->stream_id
);
2202 ret
= ustctl_get_instance_id(ustream
, &index
->stream_instance_id
);
2204 PERROR("ustctl_get_instance_id");
2207 index
->stream_instance_id
= htobe64(index
->stream_instance_id
);
2209 ret
= ustctl_get_sequence_number(ustream
, &index
->packet_seq_num
);
2211 PERROR("ustctl_get_sequence_number");
2214 index
->packet_seq_num
= htobe64(index
->packet_seq_num
);
2221 void metadata_stream_reset_cache(struct lttng_consumer_stream
*stream
,
2222 struct consumer_metadata_cache
*cache
)
2224 DBG("Metadata stream update to version %" PRIu64
,
2226 stream
->ust_metadata_pushed
= 0;
2227 stream
->metadata_version
= cache
->version
;
2228 stream
->reset_metadata_flag
= 1;
2232 * Check if the version of the metadata stream and metadata cache match.
2233 * If the cache got updated, reset the metadata stream.
2234 * The stream lock and metadata cache lock MUST be held.
2235 * Return 0 on success, a negative value on error.
2238 int metadata_stream_check_version(struct lttng_consumer_stream
*stream
)
2241 struct consumer_metadata_cache
*cache
= stream
->chan
->metadata_cache
;
2243 if (cache
->version
== stream
->metadata_version
) {
2246 metadata_stream_reset_cache(stream
, cache
);
2253 * Write up to one packet from the metadata cache to the channel.
2255 * Returns the number of bytes pushed in the cache, or a negative value
2259 int commit_one_metadata_packet(struct lttng_consumer_stream
*stream
)
2264 pthread_mutex_lock(&stream
->chan
->metadata_cache
->lock
);
2265 ret
= metadata_stream_check_version(stream
);
2269 if (stream
->chan
->metadata_cache
->max_offset
2270 == stream
->ust_metadata_pushed
) {
2275 write_len
= ustctl_write_one_packet_to_channel(stream
->chan
->uchan
,
2276 &stream
->chan
->metadata_cache
->data
[stream
->ust_metadata_pushed
],
2277 stream
->chan
->metadata_cache
->max_offset
2278 - stream
->ust_metadata_pushed
);
2279 assert(write_len
!= 0);
2280 if (write_len
< 0) {
2281 ERR("Writing one metadata packet");
2285 stream
->ust_metadata_pushed
+= write_len
;
2287 assert(stream
->chan
->metadata_cache
->max_offset
>=
2288 stream
->ust_metadata_pushed
);
2292 pthread_mutex_unlock(&stream
->chan
->metadata_cache
->lock
);
2298 * Sync metadata meaning request them to the session daemon and snapshot to the
2299 * metadata thread can consumer them.
2301 * Metadata stream lock is held here, but we need to release it when
2302 * interacting with sessiond, else we cause a deadlock with live
2303 * awaiting on metadata to be pushed out.
2305 * Return 0 if new metadatda is available, EAGAIN if the metadata stream
2306 * is empty or a negative value on error.
2308 int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data
*ctx
,
2309 struct lttng_consumer_stream
*metadata
)
2317 pthread_mutex_unlock(&metadata
->lock
);
2319 * Request metadata from the sessiond, but don't wait for the flush
2320 * because we locked the metadata thread.
2322 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata
->chan
, 0, 0);
2323 pthread_mutex_lock(&metadata
->lock
);
2328 ret
= commit_one_metadata_packet(metadata
);
2331 } else if (ret
> 0) {
2335 ustctl_flush_buffer(metadata
->ustream
, 1);
2336 ret
= ustctl_snapshot(metadata
->ustream
);
2338 if (errno
!= EAGAIN
) {
2339 ERR("Sync metadata, taking UST snapshot");
2342 DBG("No new metadata when syncing them.");
2343 /* No new metadata, exit. */
2349 * After this flush, we still need to extract metadata.
2360 * Return 0 on success else a negative value.
2362 static int notify_if_more_data(struct lttng_consumer_stream
*stream
,
2363 struct lttng_consumer_local_data
*ctx
)
2366 struct ustctl_consumer_stream
*ustream
;
2371 ustream
= stream
->ustream
;
2374 * First, we are going to check if there is a new subbuffer available
2375 * before reading the stream wait_fd.
2377 /* Get the next subbuffer */
2378 ret
= ustctl_get_next_subbuf(ustream
);
2380 /* No more data found, flag the stream. */
2381 stream
->has_data
= 0;
2386 ret
= ustctl_put_subbuf(ustream
);
2389 /* This stream still has data. Flag it and wake up the data thread. */
2390 stream
->has_data
= 1;
2392 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !ctx
->has_wakeup
) {
2395 writelen
= lttng_pipe_write(ctx
->consumer_wakeup_pipe
, "!", 1);
2396 if (writelen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2401 /* The wake up pipe has been notified. */
2402 ctx
->has_wakeup
= 1;
2411 int update_stream_stats(struct lttng_consumer_stream
*stream
)
2414 uint64_t seq
, discarded
;
2416 ret
= ustctl_get_sequence_number(stream
->ustream
, &seq
);
2418 PERROR("ustctl_get_sequence_number");
2422 * Start the sequence when we extract the first packet in case we don't
2423 * start at 0 (for example if a consumer is not connected to the
2424 * session immediately after the beginning).
2426 if (stream
->last_sequence_number
== -1ULL) {
2427 stream
->last_sequence_number
= seq
;
2428 } else if (seq
> stream
->last_sequence_number
) {
2429 stream
->chan
->lost_packets
+= seq
-
2430 stream
->last_sequence_number
- 1;
2432 /* seq <= last_sequence_number */
2433 ERR("Sequence number inconsistent : prev = %" PRIu64
2434 ", current = %" PRIu64
,
2435 stream
->last_sequence_number
, seq
);
2439 stream
->last_sequence_number
= seq
;
2441 ret
= ustctl_get_events_discarded(stream
->ustream
, &discarded
);
2443 PERROR("kernctl_get_events_discarded");
2446 if (discarded
< stream
->last_discarded_events
) {
2448 * Overflow has occurred. We assume only one wrap-around
2451 stream
->chan
->discarded_events
+=
2452 (1ULL << (CAA_BITS_PER_LONG
- 1)) -
2453 stream
->last_discarded_events
+ discarded
;
2455 stream
->chan
->discarded_events
+= discarded
-
2456 stream
->last_discarded_events
;
2458 stream
->last_discarded_events
= discarded
;
2466 * Read subbuffer from the given stream.
2468 * Stream lock MUST be acquired.
2470 * Return 0 on success else a negative value.
2472 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
2473 struct lttng_consumer_local_data
*ctx
)
2475 unsigned long len
, subbuf_size
, padding
;
2476 int err
, write_index
= 1;
2478 struct ustctl_consumer_stream
*ustream
;
2479 struct ctf_packet_index index
;
2480 const char *subbuf_addr
;
2481 struct lttng_buffer_view subbuf_view
;
2484 assert(stream
->ustream
);
2487 DBG("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
2490 /* Ease our life for what's next. */
2491 ustream
= stream
->ustream
;
2494 * We can consume the 1 byte written into the wait_fd by UST. Don't trigger
2495 * error if we cannot read this one byte (read returns 0), or if the error
2496 * is EAGAIN or EWOULDBLOCK.
2498 * This is only done when the stream is monitored by a thread, before the
2499 * flush is done after a hangup and if the stream is not flagged with data
2500 * since there might be nothing to consume in the wait fd but still have
2501 * data available flagged by the consumer wake up pipe.
2503 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !stream
->has_data
) {
2507 readlen
= lttng_read(stream
->wait_fd
, &dummy
, 1);
2508 if (readlen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2515 /* Get the next subbuffer */
2516 err
= ustctl_get_next_subbuf(ustream
);
2519 * Populate metadata info if the existing info has
2520 * already been read.
2522 if (stream
->metadata_flag
) {
2523 ret
= commit_one_metadata_packet(stream
);
2527 ustctl_flush_buffer(stream
->ustream
, 1);
2531 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
2533 * This is a debug message even for single-threaded consumer,
2534 * because poll() have more relaxed criterions than get subbuf,
2535 * so get_subbuf may fail for short race windows where poll()
2536 * would issue wakeups.
2538 DBG("Reserving sub buffer failed (everything is normal, "
2539 "it is due to concurrency) [ret: %d]", err
);
2542 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
2544 if (!stream
->metadata_flag
) {
2545 index
.offset
= htobe64(stream
->out_fd_offset
);
2546 ret
= get_index_values(&index
, ustream
);
2548 err
= ustctl_put_subbuf(ustream
);
2553 /* Update the stream's sequence and discarded events count. */
2554 ret
= update_stream_stats(stream
);
2556 PERROR("kernctl_get_events_discarded");
2557 err
= ustctl_put_subbuf(ustream
);
2565 /* Get the full padded subbuffer size */
2566 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
2569 /* Get subbuffer data size (without padding) */
2570 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
2573 /* Make sure we don't get a subbuffer size bigger than the padded */
2574 assert(len
>= subbuf_size
);
2576 padding
= len
- subbuf_size
;
2578 ret
= get_current_subbuf_addr(stream
, &subbuf_addr
);
2581 goto error_put_subbuf
;
2584 subbuf_view
= lttng_buffer_view_init(subbuf_addr
, 0, len
);
2586 /* write the subbuffer to the tracefile */
2587 ret
= lttng_consumer_on_read_subbuffer_mmap(
2588 ctx
, stream
, &subbuf_view
, padding
, &index
);
2590 * The mmap operation should write subbuf_size amount of data when
2591 * network streaming or the full padding (len) size when we are _not_
2594 if ((ret
!= subbuf_size
&& stream
->relayd_id
!= (uint64_t) -1ULL) ||
2595 (ret
!= len
&& stream
->relayd_id
== (uint64_t) -1ULL)) {
2597 * Display the error but continue processing to try to release the
2598 * subbuffer. This is a DBG statement since any unexpected kill or
2599 * signal, the application gets unregistered, relayd gets closed or
2600 * anything that affects the buffer lifetime will trigger this error.
2601 * So, for the sake of the user, don't print this error since it can
2602 * happen and it is OK with the code flow.
2604 DBG("Error writing to tracefile "
2605 "(ret: %ld != len: %lu != subbuf_size: %lu)",
2606 ret
, len
, subbuf_size
);
2610 err
= ustctl_put_next_subbuf(ustream
);
2614 * This will consumer the byte on the wait_fd if and only if there is not
2615 * next subbuffer to be acquired.
2617 if (!stream
->metadata_flag
) {
2618 ret
= notify_if_more_data(stream
, ctx
);
2624 /* Write index if needed. */
2629 if (stream
->chan
->live_timer_interval
&& !stream
->metadata_flag
) {
2631 * In live, block until all the metadata is sent.
2633 pthread_mutex_lock(&stream
->metadata_timer_lock
);
2634 assert(!stream
->missed_metadata_flush
);
2635 stream
->waiting_on_metadata
= true;
2636 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2638 err
= consumer_stream_sync_metadata(ctx
, stream
->session_id
);
2640 pthread_mutex_lock(&stream
->metadata_timer_lock
);
2641 stream
->waiting_on_metadata
= false;
2642 if (stream
->missed_metadata_flush
) {
2643 stream
->missed_metadata_flush
= false;
2644 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2645 (void) consumer_flush_ust_index(stream
);
2647 pthread_mutex_unlock(&stream
->metadata_timer_lock
);
2655 assert(!stream
->metadata_flag
);
2656 err
= consumer_stream_write_index(stream
, &index
);
2666 * Called when a stream is created.
2668 * Return 0 on success or else a negative value.
2670 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
2676 /* Don't create anything if this is set for streaming. */
2677 if (stream
->relayd_id
== (uint64_t) -1ULL && stream
->chan
->monitor
) {
2678 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
2679 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
2680 stream
->uid
, stream
->gid
, NULL
);
2684 stream
->out_fd
= ret
;
2685 stream
->tracefile_size_current
= 0;
2687 if (!stream
->metadata_flag
) {
2688 struct lttng_index_file
*index_file
;
2690 index_file
= lttng_index_file_create(stream
->chan
->pathname
,
2691 stream
->name
, stream
->uid
, stream
->gid
,
2692 stream
->chan
->tracefile_size
,
2693 stream
->tracefile_count_current
,
2694 CTF_INDEX_MAJOR
, CTF_INDEX_MINOR
);
2698 stream
->index_file
= index_file
;
2708 * Check if data is still being extracted from the buffers for a specific
2709 * stream. Consumer data lock MUST be acquired before calling this function
2710 * and the stream lock.
2712 * Return 1 if the traced data are still getting read else 0 meaning that the
2713 * data is available for trace viewer reading.
2715 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
2720 assert(stream
->ustream
);
2722 DBG("UST consumer checking data pending");
2724 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
2729 if (stream
->chan
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
2730 uint64_t contiguous
, pushed
;
2732 /* Ease our life a bit. */
2733 contiguous
= stream
->chan
->metadata_cache
->max_offset
;
2734 pushed
= stream
->ust_metadata_pushed
;
2737 * We can simply check whether all contiguously available data
2738 * has been pushed to the ring buffer, since the push operation
2739 * is performed within get_next_subbuf(), and because both
2740 * get_next_subbuf() and put_next_subbuf() are issued atomically
2741 * thanks to the stream lock within
2742 * lttng_ustconsumer_read_subbuffer(). This basically means that
2743 * whetnever ust_metadata_pushed is incremented, the associated
2744 * metadata has been consumed from the metadata stream.
2746 DBG("UST consumer metadata pending check: contiguous %" PRIu64
" vs pushed %" PRIu64
,
2747 contiguous
, pushed
);
2748 assert(((int64_t) (contiguous
- pushed
)) >= 0);
2749 if ((contiguous
!= pushed
) ||
2750 (((int64_t) contiguous
- pushed
) > 0 || contiguous
== 0)) {
2751 ret
= 1; /* Data is pending */
2755 ret
= ustctl_get_next_subbuf(stream
->ustream
);
2758 * There is still data so let's put back this
2761 ret
= ustctl_put_subbuf(stream
->ustream
);
2763 ret
= 1; /* Data is pending */
2768 /* Data is NOT pending so ready to be read. */
2776 * Stop a given metadata channel timer if enabled and close the wait fd which
2777 * is the poll pipe of the metadata stream.
2779 * This MUST be called with the metadata channel acquired.
2781 void lttng_ustconsumer_close_metadata(struct lttng_consumer_channel
*metadata
)
2786 assert(metadata
->type
== CONSUMER_CHANNEL_TYPE_METADATA
);
2788 DBG("Closing metadata channel key %" PRIu64
, metadata
->key
);
2790 if (metadata
->switch_timer_enabled
== 1) {
2791 consumer_timer_switch_stop(metadata
);
2794 if (!metadata
->metadata_stream
) {
2799 * Closing write side so the thread monitoring the stream wakes up if any
2800 * and clean the metadata stream.
2802 if (metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] >= 0) {
2803 ret
= close(metadata
->metadata_stream
->ust_metadata_poll_pipe
[1]);
2805 PERROR("closing metadata pipe write side");
2807 metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] = -1;
2815 * Close every metadata stream wait fd of the metadata hash table. This
2816 * function MUST be used very carefully so not to run into a race between the
2817 * metadata thread handling streams and this function closing their wait fd.
2819 * For UST, this is used when the session daemon hangs up. Its the metadata
2820 * producer so calling this is safe because we are assured that no state change
2821 * can occur in the metadata thread for the streams in the hash table.
2823 void lttng_ustconsumer_close_all_metadata(struct lttng_ht
*metadata_ht
)
2825 struct lttng_ht_iter iter
;
2826 struct lttng_consumer_stream
*stream
;
2828 assert(metadata_ht
);
2829 assert(metadata_ht
->ht
);
2831 DBG("UST consumer closing all metadata streams");
2834 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
2837 health_code_update();
2839 pthread_mutex_lock(&stream
->chan
->lock
);
2840 lttng_ustconsumer_close_metadata(stream
->chan
);
2841 pthread_mutex_unlock(&stream
->chan
->lock
);
2847 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
2851 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
2853 ERR("Unable to close wakeup fd");
2858 * Please refer to consumer-timer.c before adding any lock within this
2859 * function or any of its callees. Timers have a very strict locking
2860 * semantic with respect to teardown. Failure to respect this semantic
2861 * introduces deadlocks.
2863 * DON'T hold the metadata lock when calling this function, else this
2864 * can cause deadlock involving consumer awaiting for metadata to be
2865 * pushed out due to concurrent interaction with the session daemon.
2867 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
2868 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
2870 struct lttcomm_metadata_request_msg request
;
2871 struct lttcomm_consumer_msg msg
;
2872 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
2873 uint64_t len
, key
, offset
, version
;
2877 assert(channel
->metadata_cache
);
2879 memset(&request
, 0, sizeof(request
));
2881 /* send the metadata request to sessiond */
2882 switch (consumer_data
.type
) {
2883 case LTTNG_CONSUMER64_UST
:
2884 request
.bits_per_long
= 64;
2886 case LTTNG_CONSUMER32_UST
:
2887 request
.bits_per_long
= 32;
2890 request
.bits_per_long
= 0;
2894 request
.session_id
= channel
->session_id
;
2895 request
.session_id_per_pid
= channel
->session_id_per_pid
;
2897 * Request the application UID here so the metadata of that application can
2898 * be sent back. The channel UID corresponds to the user UID of the session
2899 * used for the rights on the stream file(s).
2901 request
.uid
= channel
->ust_app_uid
;
2902 request
.key
= channel
->key
;
2904 DBG("Sending metadata request to sessiond, session id %" PRIu64
2905 ", per-pid %" PRIu64
", app UID %u and channel key %" PRIu64
,
2906 request
.session_id
, request
.session_id_per_pid
, request
.uid
,
2909 pthread_mutex_lock(&ctx
->metadata_socket_lock
);
2911 health_code_update();
2913 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
2916 ERR("Asking metadata to sessiond");
2920 health_code_update();
2922 /* Receive the metadata from sessiond */
2923 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
2925 if (ret
!= sizeof(msg
)) {
2926 DBG("Consumer received unexpected message size %d (expects %zu)",
2928 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
2930 * The ret value might 0 meaning an orderly shutdown but this is ok
2931 * since the caller handles this.
2936 health_code_update();
2938 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
2939 /* No registry found */
2940 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2944 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
2945 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
2950 len
= msg
.u
.push_metadata
.len
;
2951 key
= msg
.u
.push_metadata
.key
;
2952 offset
= msg
.u
.push_metadata
.target_offset
;
2953 version
= msg
.u
.push_metadata
.version
;
2955 assert(key
== channel
->key
);
2957 DBG("No new metadata to receive for key %" PRIu64
, key
);
2960 health_code_update();
2962 /* Tell session daemon we are ready to receive the metadata. */
2963 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2964 LTTCOMM_CONSUMERD_SUCCESS
);
2965 if (ret
< 0 || len
== 0) {
2967 * Somehow, the session daemon is not responding anymore or there is
2968 * nothing to receive.
2973 health_code_update();
2975 ret
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
2976 key
, offset
, len
, version
, channel
, timer
, wait
);
2979 * Only send the status msg if the sessiond is alive meaning a positive
2982 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret
);
2987 health_code_update();
2989 pthread_mutex_unlock(&ctx
->metadata_socket_lock
);
2994 * Return the ustctl call for the get stream id.
2996 int lttng_ustconsumer_get_stream_id(struct lttng_consumer_stream
*stream
,
2997 uint64_t *stream_id
)
3002 return ustctl_get_stream_id(stream
->ustream
, stream_id
);