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-metadata-cache.h>
43 #include <common/consumer-stream.h>
44 #include <common/consumer-timer.h>
45 #include <common/utils.h>
46 #include <common/index/index.h>
48 #include "ust-consumer.h"
50 #define UINT_MAX_STR_LEN 11 /* 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
);
90 * Add channel to internal consumer state.
92 * Returns 0 on success or else a negative value.
94 static int add_channel(struct lttng_consumer_channel
*channel
,
95 struct lttng_consumer_local_data
*ctx
)
102 if (ctx
->on_recv_channel
!= NULL
) {
103 ret
= ctx
->on_recv_channel(channel
);
105 ret
= consumer_add_channel(channel
, ctx
);
106 } else if (ret
< 0) {
107 /* Most likely an ENOMEM. */
108 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
112 ret
= consumer_add_channel(channel
, ctx
);
115 DBG("UST consumer channel added (key: %" PRIu64
")", channel
->key
);
122 * Allocate and return a consumer channel object.
124 static struct lttng_consumer_channel
*allocate_channel(uint64_t session_id
,
125 const char *pathname
, const char *name
, uid_t uid
, gid_t gid
,
126 uint64_t relayd_id
, uint64_t key
, enum lttng_event_output output
,
127 uint64_t tracefile_size
, uint64_t tracefile_count
,
128 uint64_t session_id_per_pid
, unsigned int monitor
,
129 unsigned int live_timer_interval
,
130 const char *root_shm_path
, const char *shm_path
)
135 return consumer_allocate_channel(key
, session_id
, pathname
, name
, uid
,
136 gid
, relayd_id
, output
, tracefile_size
,
137 tracefile_count
, session_id_per_pid
, monitor
,
138 live_timer_interval
, root_shm_path
, shm_path
);
142 * Allocate and return a consumer stream object. If _alloc_ret is not NULL, the
143 * error value if applicable is set in it else it is kept untouched.
145 * Return NULL on error else the newly allocated stream object.
147 static struct lttng_consumer_stream
*allocate_stream(int cpu
, int key
,
148 struct lttng_consumer_channel
*channel
,
149 struct lttng_consumer_local_data
*ctx
, int *_alloc_ret
)
152 struct lttng_consumer_stream
*stream
= NULL
;
157 stream
= consumer_allocate_stream(channel
->key
,
159 LTTNG_CONSUMER_ACTIVE_STREAM
,
169 if (stream
== NULL
) {
173 * We could not find the channel. Can happen if cpu hotplug
174 * happens while tearing down.
176 DBG3("Could not find channel");
181 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
187 stream
->chan
= channel
;
191 *_alloc_ret
= alloc_ret
;
197 * Send the given stream pointer to the corresponding thread.
199 * Returns 0 on success else a negative value.
201 static int send_stream_to_thread(struct lttng_consumer_stream
*stream
,
202 struct lttng_consumer_local_data
*ctx
)
205 struct lttng_pipe
*stream_pipe
;
207 /* Get the right pipe where the stream will be sent. */
208 if (stream
->metadata_flag
) {
209 ret
= consumer_add_metadata_stream(stream
);
211 ERR("Consumer add metadata stream %" PRIu64
" failed.",
215 stream_pipe
= ctx
->consumer_metadata_pipe
;
217 ret
= consumer_add_data_stream(stream
);
219 ERR("Consumer add stream %" PRIu64
" failed.",
223 stream_pipe
= ctx
->consumer_data_pipe
;
227 * From this point on, the stream's ownership has been moved away from
228 * the channel and becomes globally visible.
230 stream
->globally_visible
= 1;
232 ret
= lttng_pipe_write(stream_pipe
, &stream
, sizeof(stream
));
234 ERR("Consumer write %s stream to pipe %d",
235 stream
->metadata_flag
? "metadata" : "data",
236 lttng_pipe_get_writefd(stream_pipe
));
237 if (stream
->metadata_flag
) {
238 consumer_del_stream_for_metadata(stream
);
240 consumer_del_stream_for_data(stream
);
248 int get_stream_shm_path(char *stream_shm_path
, const char *shm_path
, int cpu
)
250 char cpu_nr
[UINT_MAX_STR_LEN
]; /* unsigned int max len */
253 strncpy(stream_shm_path
, shm_path
, PATH_MAX
);
254 stream_shm_path
[PATH_MAX
- 1] = '\0';
255 ret
= snprintf(cpu_nr
, UINT_MAX_STR_LEN
, "%u", cpu
);
260 strncat(stream_shm_path
, cpu_nr
,
261 PATH_MAX
- strlen(stream_shm_path
) - 1);
268 * Create streams for the given channel using liblttng-ust-ctl.
270 * Return 0 on success else a negative value.
272 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
273 struct lttng_consumer_local_data
*ctx
)
276 struct ustctl_consumer_stream
*ustream
;
277 struct lttng_consumer_stream
*stream
;
283 * While a stream is available from ustctl. When NULL is returned, we've
284 * reached the end of the possible stream for the channel.
286 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
288 int ust_metadata_pipe
[2];
290 health_code_update();
292 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& channel
->monitor
) {
293 ret
= utils_create_pipe_cloexec_nonblock(ust_metadata_pipe
);
295 ERR("Create ust metadata poll pipe");
298 wait_fd
= ust_metadata_pipe
[0];
300 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
303 /* Allocate consumer stream object. */
304 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
308 stream
->ustream
= ustream
;
310 * Store it so we can save multiple function calls afterwards since
311 * this value is used heavily in the stream threads. This is UST
312 * specific so this is why it's done after allocation.
314 stream
->wait_fd
= wait_fd
;
317 * Increment channel refcount since the channel reference has now been
318 * assigned in the allocation process above.
320 if (stream
->chan
->monitor
) {
321 uatomic_inc(&stream
->chan
->refcount
);
325 * Order is important this is why a list is used. On error, the caller
326 * should clean this list.
328 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
330 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
331 &stream
->max_sb_size
);
333 ERR("ustctl_get_max_subbuf_size failed for stream %s",
338 /* Do actions once stream has been received. */
339 if (ctx
->on_recv_stream
) {
340 ret
= ctx
->on_recv_stream(stream
);
346 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
347 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
349 /* Set next CPU stream. */
350 channel
->streams
.count
= ++cpu
;
352 /* Keep stream reference when creating metadata. */
353 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
354 channel
->metadata_stream
= stream
;
355 if (channel
->monitor
) {
356 /* Set metadata poll pipe if we created one */
357 memcpy(stream
->ust_metadata_poll_pipe
,
359 sizeof(ust_metadata_pipe
));
372 * create_posix_shm is never called concurrently within a process.
375 int create_posix_shm(void)
377 char tmp_name
[NAME_MAX
];
380 ret
= snprintf(tmp_name
, NAME_MAX
, "/ust-shm-consumer-%d", getpid());
386 * Allocate shm, and immediately unlink its shm oject, keeping
387 * only the file descriptor as a reference to the object.
388 * We specifically do _not_ use the / at the beginning of the
389 * pathname so that some OS implementations can keep it local to
390 * the process (POSIX leaves this implementation-defined).
392 shmfd
= shm_open(tmp_name
, O_CREAT
| O_EXCL
| O_RDWR
, 0700);
397 ret
= shm_unlink(tmp_name
);
398 if (ret
< 0 && errno
!= ENOENT
) {
399 PERROR("shm_unlink");
400 goto error_shm_release
;
413 static int open_ust_stream_fd(struct lttng_consumer_channel
*channel
,
414 struct ustctl_consumer_channel_attr
*attr
,
417 char shm_path
[PATH_MAX
];
420 if (!channel
->shm_path
[0]) {
421 return create_posix_shm();
423 ret
= get_stream_shm_path(shm_path
, channel
->shm_path
, cpu
);
427 return run_as_open(shm_path
,
428 O_RDWR
| O_CREAT
| O_EXCL
, S_IRUSR
| S_IWUSR
,
429 channel
->uid
, channel
->gid
);
436 * Create an UST channel with the given attributes and send it to the session
437 * daemon using the ust ctl API.
439 * Return 0 on success or else a negative value.
441 static int create_ust_channel(struct lttng_consumer_channel
*channel
,
442 struct ustctl_consumer_channel_attr
*attr
,
443 struct ustctl_consumer_channel
**ust_chanp
)
445 int ret
, nr_stream_fds
, i
, j
;
447 struct ustctl_consumer_channel
*ust_channel
;
453 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
454 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
455 "switch_timer_interval: %u, read_timer_interval: %u, "
456 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
457 attr
->num_subbuf
, attr
->switch_timer_interval
,
458 attr
->read_timer_interval
, attr
->output
, attr
->type
);
460 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
)
463 nr_stream_fds
= ustctl_get_nr_stream_per_channel();
464 stream_fds
= zmalloc(nr_stream_fds
* sizeof(*stream_fds
));
469 for (i
= 0; i
< nr_stream_fds
; i
++) {
470 stream_fds
[i
] = open_ust_stream_fd(channel
, attr
, i
);
471 if (stream_fds
[i
] < 0) {
476 ust_channel
= ustctl_create_channel(attr
, stream_fds
, nr_stream_fds
);
481 channel
->nr_stream_fds
= nr_stream_fds
;
482 channel
->stream_fds
= stream_fds
;
483 *ust_chanp
= ust_channel
;
489 for (j
= i
- 1; j
>= 0; j
--) {
492 closeret
= close(stream_fds
[j
]);
496 if (channel
->shm_path
[0]) {
497 char shm_path
[PATH_MAX
];
499 closeret
= get_stream_shm_path(shm_path
,
500 channel
->shm_path
, j
);
502 ERR("Cannot get stream shm path");
504 closeret
= run_as_unlink(shm_path
,
505 channel
->uid
, channel
->gid
);
507 PERROR("unlink %s", shm_path
);
511 /* Try to rmdir all directories under shm_path root. */
512 if (channel
->root_shm_path
[0]) {
513 (void) run_as_recursive_rmdir(channel
->root_shm_path
,
514 channel
->uid
, channel
->gid
);
522 * Send a single given stream to the session daemon using the sock.
524 * Return 0 on success else a negative value.
526 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
533 DBG("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
535 /* Send stream to session daemon. */
536 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
546 * Send channel to sessiond.
548 * Return 0 on success or else a negative value.
550 static int send_sessiond_channel(int sock
,
551 struct lttng_consumer_channel
*channel
,
552 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
554 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
555 struct lttng_consumer_stream
*stream
;
556 uint64_t net_seq_idx
= -1ULL;
562 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
564 if (channel
->relayd_id
!= (uint64_t) -1ULL) {
565 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
567 health_code_update();
569 /* Try to send the stream to the relayd if one is available. */
570 ret
= consumer_send_relayd_stream(stream
, stream
->chan
->pathname
);
573 * Flag that the relayd was the problem here probably due to a
574 * communicaton error on the socket.
579 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
581 if (net_seq_idx
== -1ULL) {
582 net_seq_idx
= stream
->net_seq_idx
;
587 /* Inform sessiond that we are about to send channel and streams. */
588 ret
= consumer_send_status_msg(sock
, ret_code
);
589 if (ret
< 0 || ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
591 * Either the session daemon is not responding or the relayd died so we
597 /* Send channel to sessiond. */
598 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
603 ret
= ustctl_channel_close_wakeup_fd(channel
->uchan
);
608 /* The channel was sent successfully to the sessiond at this point. */
609 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
611 health_code_update();
613 /* Send stream to session daemon. */
614 ret
= send_sessiond_stream(sock
, stream
);
620 /* Tell sessiond there is no more stream. */
621 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
626 DBG("UST consumer NULL stream sent to sessiond");
631 if (ret_code
!= LTTCOMM_CONSUMERD_SUCCESS
) {
638 * Creates a channel and streams and add the channel it to the channel internal
639 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
642 * Return 0 on success or else, a negative value is returned and the channel
643 * MUST be destroyed by consumer_del_channel().
645 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
646 struct lttng_consumer_channel
*channel
,
647 struct ustctl_consumer_channel_attr
*attr
)
656 * This value is still used by the kernel consumer since for the kernel,
657 * the stream ownership is not IN the consumer so we need to have the
658 * number of left stream that needs to be initialized so we can know when
659 * to delete the channel (see consumer.c).
661 * As for the user space tracer now, the consumer creates and sends the
662 * stream to the session daemon which only sends them to the application
663 * once every stream of a channel is received making this value useless
664 * because we they will be added to the poll thread before the application
665 * receives them. This ensures that a stream can not hang up during
666 * initilization of a channel.
668 channel
->nb_init_stream_left
= 0;
670 /* The reply msg status is handled in the following call. */
671 ret
= create_ust_channel(channel
, attr
, &channel
->uchan
);
676 channel
->wait_fd
= ustctl_channel_get_wait_fd(channel
->uchan
);
679 * For the snapshots (no monitor), we create the metadata streams
680 * on demand, not during the channel creation.
682 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
&& !channel
->monitor
) {
687 /* Open all streams for this channel. */
688 ret
= create_ust_streams(channel
, ctx
);
698 * Send all stream of a channel to the right thread handling it.
700 * On error, return a negative value else 0 on success.
702 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
703 struct lttng_consumer_local_data
*ctx
)
706 struct lttng_consumer_stream
*stream
, *stmp
;
711 /* Send streams to the corresponding thread. */
712 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
715 health_code_update();
717 /* Sending the stream to the thread. */
718 ret
= send_stream_to_thread(stream
, ctx
);
721 * If we are unable to send the stream to the thread, there is
722 * a big problem so just stop everything.
724 /* Remove node from the channel stream list. */
725 cds_list_del(&stream
->send_node
);
729 /* Remove node from the channel stream list. */
730 cds_list_del(&stream
->send_node
);
739 * Flush channel's streams using the given key to retrieve the channel.
741 * Return 0 on success else an LTTng error code.
743 static int flush_channel(uint64_t chan_key
)
746 struct lttng_consumer_channel
*channel
;
747 struct lttng_consumer_stream
*stream
;
749 struct lttng_ht_iter iter
;
751 DBG("UST consumer flush channel key %" PRIu64
, chan_key
);
754 channel
= consumer_find_channel(chan_key
);
756 ERR("UST consumer flush channel %" PRIu64
" not found", chan_key
);
757 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
761 ht
= consumer_data
.stream_per_chan_id_ht
;
763 /* For each stream of the channel id, flush it. */
764 cds_lfht_for_each_entry_duplicate(ht
->ht
,
765 ht
->hash_fct(&channel
->key
, lttng_ht_seed
), ht
->match_fct
,
766 &channel
->key
, &iter
.iter
, stream
, node_channel_id
.node
) {
768 health_code_update();
770 ustctl_flush_buffer(stream
->ustream
, 1);
778 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
779 * RCU read side lock MUST be acquired before calling this function.
781 * Return 0 on success else an LTTng error code.
783 static int close_metadata(uint64_t chan_key
)
786 struct lttng_consumer_channel
*channel
;
788 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
790 channel
= consumer_find_channel(chan_key
);
793 * This is possible if the metadata thread has issue a delete because
794 * the endpoint point of the stream hung up. There is no way the
795 * session daemon can know about it thus use a DBG instead of an actual
798 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
799 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
803 pthread_mutex_lock(&consumer_data
.lock
);
804 pthread_mutex_lock(&channel
->lock
);
806 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
810 lttng_ustconsumer_close_metadata(channel
);
813 pthread_mutex_unlock(&channel
->lock
);
814 pthread_mutex_unlock(&consumer_data
.lock
);
820 * RCU read side lock MUST be acquired before calling this function.
822 * Return 0 on success else an LTTng error code.
824 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
827 struct lttng_consumer_channel
*metadata
;
829 DBG("UST consumer setup metadata key %" PRIu64
, key
);
831 metadata
= consumer_find_channel(key
);
833 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
834 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
839 * In no monitor mode, the metadata channel has no stream(s) so skip the
840 * ownership transfer to the metadata thread.
842 if (!metadata
->monitor
) {
843 DBG("Metadata channel in no monitor");
849 * Send metadata stream to relayd if one available. Availability is
850 * known if the stream is still in the list of the channel.
852 if (cds_list_empty(&metadata
->streams
.head
)) {
853 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
854 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
855 goto error_no_stream
;
858 /* Send metadata stream to relayd if needed. */
859 if (metadata
->metadata_stream
->net_seq_idx
!= (uint64_t) -1ULL) {
860 ret
= consumer_send_relayd_stream(metadata
->metadata_stream
,
863 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
866 ret
= consumer_send_relayd_streams_sent(
867 metadata
->metadata_stream
->net_seq_idx
);
869 ret
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
874 ret
= send_streams_to_thread(metadata
, ctx
);
877 * If we are unable to send the stream to the thread, there is
878 * a big problem so just stop everything.
880 ret
= LTTCOMM_CONSUMERD_FATAL
;
883 /* List MUST be empty after or else it could be reused. */
884 assert(cds_list_empty(&metadata
->streams
.head
));
891 * Delete metadata channel on error. At this point, the metadata stream can
892 * NOT be monitored by the metadata thread thus having the guarantee that
893 * the stream is still in the local stream list of the channel. This call
894 * will make sure to clean that list.
896 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
897 cds_list_del(&metadata
->metadata_stream
->send_node
);
898 metadata
->metadata_stream
= NULL
;
905 * Snapshot the whole metadata.
907 * Returns 0 on success, < 0 on error
909 static int snapshot_metadata(uint64_t key
, char *path
, uint64_t relayd_id
,
910 struct lttng_consumer_local_data
*ctx
)
913 struct lttng_consumer_channel
*metadata_channel
;
914 struct lttng_consumer_stream
*metadata_stream
;
919 DBG("UST consumer snapshot metadata with key %" PRIu64
" at path %s",
924 metadata_channel
= consumer_find_channel(key
);
925 if (!metadata_channel
) {
926 ERR("UST snapshot metadata channel not found for key %" PRIu64
,
931 assert(!metadata_channel
->monitor
);
933 health_code_update();
936 * Ask the sessiond if we have new metadata waiting and update the
937 * consumer metadata cache.
939 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
, 0, 1);
944 health_code_update();
947 * The metadata stream is NOT created in no monitor mode when the channel
948 * is created on a sessiond ask channel command.
950 ret
= create_ust_streams(metadata_channel
, ctx
);
955 metadata_stream
= metadata_channel
->metadata_stream
;
956 assert(metadata_stream
);
958 if (relayd_id
!= (uint64_t) -1ULL) {
959 metadata_stream
->net_seq_idx
= relayd_id
;
960 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
965 ret
= utils_create_stream_file(path
, metadata_stream
->name
,
966 metadata_stream
->chan
->tracefile_size
,
967 metadata_stream
->tracefile_count_current
,
968 metadata_stream
->uid
, metadata_stream
->gid
, NULL
);
972 metadata_stream
->out_fd
= ret
;
973 metadata_stream
->tracefile_size_current
= 0;
977 health_code_update();
979 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
);
987 * Clean up the stream completly because the next snapshot will use a new
990 consumer_stream_destroy(metadata_stream
, NULL
);
991 cds_list_del(&metadata_stream
->send_node
);
992 metadata_channel
->metadata_stream
= NULL
;
1000 * Take a snapshot of all the stream of a channel.
1002 * Returns 0 on success, < 0 on error
1004 static int snapshot_channel(uint64_t key
, char *path
, uint64_t relayd_id
,
1005 uint64_t nb_packets_per_stream
, struct lttng_consumer_local_data
*ctx
)
1008 unsigned use_relayd
= 0;
1009 unsigned long consumed_pos
, produced_pos
;
1010 struct lttng_consumer_channel
*channel
;
1011 struct lttng_consumer_stream
*stream
;
1018 if (relayd_id
!= (uint64_t) -1ULL) {
1022 channel
= consumer_find_channel(key
);
1024 ERR("UST snapshot channel not found for key %" PRIu64
, key
);
1028 assert(!channel
->monitor
);
1029 DBG("UST consumer snapshot channel %" PRIu64
, key
);
1031 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
1033 health_code_update();
1035 /* Lock stream because we are about to change its state. */
1036 pthread_mutex_lock(&stream
->lock
);
1037 stream
->net_seq_idx
= relayd_id
;
1040 ret
= consumer_send_relayd_stream(stream
, path
);
1045 ret
= utils_create_stream_file(path
, stream
->name
,
1046 stream
->chan
->tracefile_size
,
1047 stream
->tracefile_count_current
,
1048 stream
->uid
, stream
->gid
, NULL
);
1052 stream
->out_fd
= ret
;
1053 stream
->tracefile_size_current
= 0;
1055 DBG("UST consumer snapshot stream %s/%s (%" PRIu64
")", path
,
1056 stream
->name
, stream
->key
);
1058 if (relayd_id
!= -1ULL) {
1059 ret
= consumer_send_relayd_streams_sent(relayd_id
);
1065 ustctl_flush_buffer(stream
->ustream
, 1);
1067 ret
= lttng_ustconsumer_take_snapshot(stream
);
1069 ERR("Taking UST snapshot");
1073 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
1075 ERR("Produced UST snapshot position");
1079 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
1081 ERR("Consumerd UST snapshot position");
1086 * The original value is sent back if max stream size is larger than
1087 * the possible size of the snapshot. Also, we assume that the session
1088 * daemon should never send a maximum stream size that is lower than
1091 consumed_pos
= consumer_get_consume_start_pos(consumed_pos
,
1092 produced_pos
, nb_packets_per_stream
,
1093 stream
->max_sb_size
);
1095 while (consumed_pos
< produced_pos
) {
1097 unsigned long len
, padded_len
;
1099 health_code_update();
1101 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
1103 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
1105 if (ret
!= -EAGAIN
) {
1106 PERROR("ustctl_get_subbuf snapshot");
1107 goto error_close_stream
;
1109 DBG("UST consumer get subbuf failed. Skipping it.");
1110 consumed_pos
+= stream
->max_sb_size
;
1114 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
1116 ERR("Snapshot ustctl_get_subbuf_size");
1117 goto error_put_subbuf
;
1120 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
1122 ERR("Snapshot ustctl_get_padded_subbuf_size");
1123 goto error_put_subbuf
;
1126 read_len
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, len
,
1127 padded_len
- len
, NULL
);
1129 if (read_len
!= len
) {
1131 goto error_put_subbuf
;
1134 if (read_len
!= padded_len
) {
1136 goto error_put_subbuf
;
1140 ret
= ustctl_put_subbuf(stream
->ustream
);
1142 ERR("Snapshot ustctl_put_subbuf");
1143 goto error_close_stream
;
1145 consumed_pos
+= stream
->max_sb_size
;
1148 /* Simply close the stream so we can use it on the next snapshot. */
1149 consumer_stream_close(stream
);
1150 pthread_mutex_unlock(&stream
->lock
);
1157 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
1158 ERR("Snapshot ustctl_put_subbuf");
1161 consumer_stream_close(stream
);
1163 pthread_mutex_unlock(&stream
->lock
);
1170 * Receive the metadata updates from the sessiond.
1172 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
1173 uint64_t len
, struct lttng_consumer_channel
*channel
,
1174 int timer
, int wait
)
1176 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1179 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
1181 metadata_str
= zmalloc(len
* sizeof(char));
1182 if (!metadata_str
) {
1183 PERROR("zmalloc metadata string");
1184 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
1188 health_code_update();
1190 /* Receive metadata string. */
1191 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1193 /* Session daemon is dead so return gracefully. */
1198 health_code_update();
1200 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1201 ret
= consumer_metadata_cache_write(channel
, offset
, len
, metadata_str
);
1203 /* Unable to handle metadata. Notify session daemon. */
1204 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1206 * Skip metadata flush on write error since the offset and len might
1207 * not have been updated which could create an infinite loop below when
1208 * waiting for the metadata cache to be flushed.
1210 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1213 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1218 while (consumer_metadata_cache_flushed(channel
, offset
+ len
, timer
)) {
1219 DBG("Waiting for metadata to be flushed");
1221 health_code_update();
1223 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1233 * Receive command from session daemon and process it.
1235 * Return 1 on success else a negative value or 0.
1237 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1238 int sock
, struct pollfd
*consumer_sockpoll
)
1241 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1242 struct lttcomm_consumer_msg msg
;
1243 struct lttng_consumer_channel
*channel
= NULL
;
1245 health_code_update();
1247 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1248 if (ret
!= sizeof(msg
)) {
1249 DBG("Consumer received unexpected message size %zd (expects %zu)",
1252 * The ret value might 0 meaning an orderly shutdown but this is ok
1253 * since the caller handles this.
1256 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1262 health_code_update();
1265 assert(msg
.cmd_type
!= LTTNG_CONSUMER_STOP
);
1267 health_code_update();
1269 /* relayd needs RCU read-side lock */
1272 switch (msg
.cmd_type
) {
1273 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1275 /* Session daemon status message are handled in the following call. */
1276 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1277 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1278 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
,
1279 msg
.u
.relayd_sock
.relayd_session_id
);
1282 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1284 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1285 struct consumer_relayd_sock_pair
*relayd
;
1287 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1289 /* Get relayd reference if exists. */
1290 relayd
= consumer_find_relayd(index
);
1291 if (relayd
== NULL
) {
1292 DBG("Unable to find relayd %" PRIu64
, index
);
1293 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
1297 * Each relayd socket pair has a refcount of stream attached to it
1298 * which tells if the relayd is still active or not depending on the
1301 * This will set the destroy flag of the relayd object and destroy it
1302 * if the refcount reaches zero when called.
1304 * The destroy can happen either here or when a stream fd hangs up.
1307 consumer_flag_relayd_for_destroy(relayd
);
1310 goto end_msg_sessiond
;
1312 case LTTNG_CONSUMER_UPDATE_STREAM
:
1317 case LTTNG_CONSUMER_DATA_PENDING
:
1319 int ret
, is_data_pending
;
1320 uint64_t id
= msg
.u
.data_pending
.session_id
;
1322 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1324 is_data_pending
= consumer_data_pending(id
);
1326 /* Send back returned value to session daemon */
1327 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1328 sizeof(is_data_pending
));
1330 DBG("Error when sending the data pending ret code: %d", ret
);
1335 * No need to send back a status message since the data pending
1336 * returned value is the response.
1340 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1343 struct ustctl_consumer_channel_attr attr
;
1345 /* Create a plain object and reserve a channel key. */
1346 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
1347 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
1348 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
1349 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
1350 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1351 msg
.u
.ask_channel
.tracefile_size
,
1352 msg
.u
.ask_channel
.tracefile_count
,
1353 msg
.u
.ask_channel
.session_id_per_pid
,
1354 msg
.u
.ask_channel
.monitor
,
1355 msg
.u
.ask_channel
.live_timer_interval
,
1356 msg
.u
.ask_channel
.root_shm_path
,
1357 msg
.u
.ask_channel
.shm_path
);
1359 goto end_channel_error
;
1363 * Assign UST application UID to the channel. This value is ignored for
1364 * per PID buffers. This is specific to UST thus setting this after the
1367 channel
->ust_app_uid
= msg
.u
.ask_channel
.ust_app_uid
;
1369 /* Build channel attributes from received message. */
1370 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1371 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1372 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1373 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1374 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1375 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1376 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1378 /* Match channel buffer type to the UST abi. */
1379 switch (msg
.u
.ask_channel
.output
) {
1380 case LTTNG_EVENT_MMAP
:
1382 attr
.output
= LTTNG_UST_MMAP
;
1386 /* Translate and save channel type. */
1387 switch (msg
.u
.ask_channel
.type
) {
1388 case LTTNG_UST_CHAN_PER_CPU
:
1389 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1390 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1392 * Set refcount to 1 for owner. Below, we will
1393 * pass ownership to the
1394 * consumer_thread_channel_poll() thread.
1396 channel
->refcount
= 1;
1398 case LTTNG_UST_CHAN_METADATA
:
1399 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1400 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1407 health_code_update();
1409 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
1411 goto end_channel_error
;
1414 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1415 ret
= consumer_metadata_cache_allocate(channel
);
1417 ERR("Allocating metadata cache");
1418 goto end_channel_error
;
1420 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1421 attr
.switch_timer_interval
= 0;
1423 consumer_timer_live_start(channel
,
1424 msg
.u
.ask_channel
.live_timer_interval
);
1427 health_code_update();
1430 * Add the channel to the internal state AFTER all streams were created
1431 * and successfully sent to session daemon. This way, all streams must
1432 * be ready before this channel is visible to the threads.
1433 * If add_channel succeeds, ownership of the channel is
1434 * passed to consumer_thread_channel_poll().
1436 ret
= add_channel(channel
, ctx
);
1438 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1439 if (channel
->switch_timer_enabled
== 1) {
1440 consumer_timer_switch_stop(channel
);
1442 consumer_metadata_cache_destroy(channel
);
1444 if (channel
->live_timer_enabled
== 1) {
1445 consumer_timer_live_stop(channel
);
1447 goto end_channel_error
;
1450 health_code_update();
1453 * Channel and streams are now created. Inform the session daemon that
1454 * everything went well and should wait to receive the channel and
1455 * streams with ustctl API.
1457 ret
= consumer_send_status_channel(sock
, channel
);
1460 * There is probably a problem on the socket.
1467 case LTTNG_CONSUMER_GET_CHANNEL
:
1469 int ret
, relayd_err
= 0;
1470 uint64_t key
= msg
.u
.get_channel
.key
;
1471 struct lttng_consumer_channel
*channel
;
1473 channel
= consumer_find_channel(key
);
1475 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1476 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1477 goto end_msg_sessiond
;
1480 health_code_update();
1482 /* Send everything to sessiond. */
1483 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1487 * We were unable to send to the relayd the stream so avoid
1488 * sending back a fatal error to the thread since this is OK
1489 * and the consumer can continue its work. The above call
1490 * has sent the error status message to the sessiond.
1495 * The communicaton was broken hence there is a bad state between
1496 * the consumer and sessiond so stop everything.
1501 health_code_update();
1504 * In no monitor mode, the streams ownership is kept inside the channel
1505 * so don't send them to the data thread.
1507 if (!channel
->monitor
) {
1508 goto end_msg_sessiond
;
1511 ret
= send_streams_to_thread(channel
, ctx
);
1514 * If we are unable to send the stream to the thread, there is
1515 * a big problem so just stop everything.
1519 /* List MUST be empty after or else it could be reused. */
1520 assert(cds_list_empty(&channel
->streams
.head
));
1521 goto end_msg_sessiond
;
1523 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1525 uint64_t key
= msg
.u
.destroy_channel
.key
;
1528 * Only called if streams have not been sent to stream
1529 * manager thread. However, channel has been sent to
1530 * channel manager thread.
1532 notify_thread_del_channel(ctx
, key
);
1533 goto end_msg_sessiond
;
1535 case LTTNG_CONSUMER_CLOSE_METADATA
:
1539 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1544 goto end_msg_sessiond
;
1546 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1550 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1555 goto end_msg_sessiond
;
1557 case LTTNG_CONSUMER_PUSH_METADATA
:
1560 uint64_t len
= msg
.u
.push_metadata
.len
;
1561 uint64_t key
= msg
.u
.push_metadata
.key
;
1562 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1563 struct lttng_consumer_channel
*channel
;
1565 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1568 channel
= consumer_find_channel(key
);
1571 * This is possible if the metadata creation on the consumer side
1572 * is in flight vis-a-vis a concurrent push metadata from the
1573 * session daemon. Simply return that the channel failed and the
1574 * session daemon will handle that message correctly considering
1575 * that this race is acceptable thus the DBG() statement here.
1577 DBG("UST consumer push metadata %" PRIu64
" not found", key
);
1578 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1579 goto end_msg_sessiond
;
1582 health_code_update();
1584 /* Tell session daemon we are ready to receive the metadata. */
1585 ret
= consumer_send_status_msg(sock
, LTTCOMM_CONSUMERD_SUCCESS
);
1587 /* Somehow, the session daemon is not responding anymore. */
1591 health_code_update();
1593 /* Wait for more data. */
1594 health_poll_entry();
1595 ret
= lttng_consumer_poll_socket(consumer_sockpoll
);
1601 health_code_update();
1603 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1604 len
, channel
, 0, 1);
1606 /* error receiving from sessiond */
1610 goto end_msg_sessiond
;
1613 case LTTNG_CONSUMER_SETUP_METADATA
:
1617 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1621 goto end_msg_sessiond
;
1623 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1625 if (msg
.u
.snapshot_channel
.metadata
) {
1626 ret
= snapshot_metadata(msg
.u
.snapshot_channel
.key
,
1627 msg
.u
.snapshot_channel
.pathname
,
1628 msg
.u
.snapshot_channel
.relayd_id
,
1631 ERR("Snapshot metadata failed");
1632 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1635 ret
= snapshot_channel(msg
.u
.snapshot_channel
.key
,
1636 msg
.u
.snapshot_channel
.pathname
,
1637 msg
.u
.snapshot_channel
.relayd_id
,
1638 msg
.u
.snapshot_channel
.nb_packets_per_stream
,
1641 ERR("Snapshot channel failed");
1642 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1646 health_code_update();
1647 ret
= consumer_send_status_msg(sock
, ret_code
);
1649 /* Somehow, the session daemon is not responding anymore. */
1652 health_code_update();
1662 health_code_update();
1665 * Return 1 to indicate success since the 0 value can be a socket
1666 * shutdown during the recv() or send() call.
1672 * The returned value here is not useful since either way we'll return 1 to
1673 * the caller because the session daemon socket management is done
1674 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1676 ret
= consumer_send_status_msg(sock
, ret_code
);
1682 health_code_update();
1688 * Free channel here since no one has a reference to it. We don't
1689 * free after that because a stream can store this pointer.
1691 destroy_channel(channel
);
1693 /* We have to send a status channel message indicating an error. */
1694 ret
= consumer_send_status_channel(sock
, NULL
);
1696 /* Stop everything if session daemon can not be notified. */
1701 health_code_update();
1706 /* This will issue a consumer stop. */
1711 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1712 * compiled out, we isolate it in this library.
1714 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1718 assert(stream
->ustream
);
1720 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1724 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1725 * compiled out, we isolate it in this library.
1727 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1730 assert(stream
->ustream
);
1732 return ustctl_get_mmap_base(stream
->ustream
);
1736 * Take a snapshot for a specific fd
1738 * Returns 0 on success, < 0 on error
1740 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1743 assert(stream
->ustream
);
1745 return ustctl_snapshot(stream
->ustream
);
1749 * Get the produced position
1751 * Returns 0 on success, < 0 on error
1753 int lttng_ustconsumer_get_produced_snapshot(
1754 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1757 assert(stream
->ustream
);
1760 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1764 * Get the consumed position
1766 * Returns 0 on success, < 0 on error
1768 int lttng_ustconsumer_get_consumed_snapshot(
1769 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1772 assert(stream
->ustream
);
1775 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
1778 void lttng_ustconsumer_flush_buffer(struct lttng_consumer_stream
*stream
,
1782 assert(stream
->ustream
);
1784 ustctl_flush_buffer(stream
->ustream
, producer
);
1787 int lttng_ustconsumer_get_current_timestamp(
1788 struct lttng_consumer_stream
*stream
, uint64_t *ts
)
1791 assert(stream
->ustream
);
1794 return ustctl_get_current_timestamp(stream
->ustream
, ts
);
1798 * Called when the stream signal the consumer that it has hang up.
1800 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1803 assert(stream
->ustream
);
1805 ustctl_flush_buffer(stream
->ustream
, 0);
1806 stream
->hangup_flush_done
= 1;
1809 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1814 assert(chan
->uchan
);
1816 if (chan
->switch_timer_enabled
== 1) {
1817 consumer_timer_switch_stop(chan
);
1819 consumer_metadata_cache_destroy(chan
);
1820 ustctl_destroy_channel(chan
->uchan
);
1821 for (i
= 0; i
< chan
->nr_stream_fds
; i
++) {
1824 ret
= close(chan
->stream_fds
[i
]);
1828 if (chan
->shm_path
[0]) {
1829 char shm_path
[PATH_MAX
];
1831 ret
= get_stream_shm_path(shm_path
, chan
->shm_path
, i
);
1833 ERR("Cannot get stream shm path");
1835 ret
= run_as_unlink(shm_path
, chan
->uid
, chan
->gid
);
1837 PERROR("unlink %s", shm_path
);
1841 free(chan
->stream_fds
);
1842 /* Try to rmdir all directories under shm_path root. */
1843 if (chan
->root_shm_path
[0]) {
1844 (void) run_as_recursive_rmdir(chan
->root_shm_path
,
1845 chan
->uid
, chan
->gid
);
1849 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
1852 assert(stream
->ustream
);
1854 if (stream
->chan
->switch_timer_enabled
== 1) {
1855 consumer_timer_switch_stop(stream
->chan
);
1857 ustctl_destroy_stream(stream
->ustream
);
1860 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream
*stream
)
1863 assert(stream
->ustream
);
1865 return ustctl_stream_get_wakeup_fd(stream
->ustream
);
1868 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream
*stream
)
1871 assert(stream
->ustream
);
1873 return ustctl_stream_close_wakeup_fd(stream
->ustream
);
1877 * Populate index values of a UST stream. Values are set in big endian order.
1879 * Return 0 on success or else a negative value.
1881 static int get_index_values(struct ctf_packet_index
*index
,
1882 struct ustctl_consumer_stream
*ustream
)
1886 ret
= ustctl_get_timestamp_begin(ustream
, &index
->timestamp_begin
);
1888 PERROR("ustctl_get_timestamp_begin");
1891 index
->timestamp_begin
= htobe64(index
->timestamp_begin
);
1893 ret
= ustctl_get_timestamp_end(ustream
, &index
->timestamp_end
);
1895 PERROR("ustctl_get_timestamp_end");
1898 index
->timestamp_end
= htobe64(index
->timestamp_end
);
1900 ret
= ustctl_get_events_discarded(ustream
, &index
->events_discarded
);
1902 PERROR("ustctl_get_events_discarded");
1905 index
->events_discarded
= htobe64(index
->events_discarded
);
1907 ret
= ustctl_get_content_size(ustream
, &index
->content_size
);
1909 PERROR("ustctl_get_content_size");
1912 index
->content_size
= htobe64(index
->content_size
);
1914 ret
= ustctl_get_packet_size(ustream
, &index
->packet_size
);
1916 PERROR("ustctl_get_packet_size");
1919 index
->packet_size
= htobe64(index
->packet_size
);
1921 ret
= ustctl_get_stream_id(ustream
, &index
->stream_id
);
1923 PERROR("ustctl_get_stream_id");
1926 index
->stream_id
= htobe64(index
->stream_id
);
1933 * Write up to one packet from the metadata cache to the channel.
1935 * Returns the number of bytes pushed in the cache, or a negative value
1939 int commit_one_metadata_packet(struct lttng_consumer_stream
*stream
)
1944 pthread_mutex_lock(&stream
->chan
->metadata_cache
->lock
);
1945 if (stream
->chan
->metadata_cache
->contiguous
1946 == stream
->ust_metadata_pushed
) {
1951 write_len
= ustctl_write_one_packet_to_channel(stream
->chan
->uchan
,
1952 &stream
->chan
->metadata_cache
->data
[stream
->ust_metadata_pushed
],
1953 stream
->chan
->metadata_cache
->contiguous
1954 - stream
->ust_metadata_pushed
);
1955 assert(write_len
!= 0);
1956 if (write_len
< 0) {
1957 ERR("Writing one metadata packet");
1961 stream
->ust_metadata_pushed
+= write_len
;
1963 assert(stream
->chan
->metadata_cache
->contiguous
>=
1964 stream
->ust_metadata_pushed
);
1968 pthread_mutex_unlock(&stream
->chan
->metadata_cache
->lock
);
1974 * Sync metadata meaning request them to the session daemon and snapshot to the
1975 * metadata thread can consumer them.
1977 * Metadata stream lock MUST be acquired.
1979 * Return 0 if new metadatda is available, EAGAIN if the metadata stream
1980 * is empty or a negative value on error.
1982 int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data
*ctx
,
1983 struct lttng_consumer_stream
*metadata
)
1992 * Request metadata from the sessiond, but don't wait for the flush
1993 * because we locked the metadata thread.
1995 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata
->chan
, 0, 0);
2000 ret
= commit_one_metadata_packet(metadata
);
2003 } else if (ret
> 0) {
2007 ustctl_flush_buffer(metadata
->ustream
, 1);
2008 ret
= ustctl_snapshot(metadata
->ustream
);
2010 if (errno
!= EAGAIN
) {
2011 ERR("Sync metadata, taking UST snapshot");
2014 DBG("No new metadata when syncing them.");
2015 /* No new metadata, exit. */
2021 * After this flush, we still need to extract metadata.
2032 * Return 0 on success else a negative value.
2034 static int notify_if_more_data(struct lttng_consumer_stream
*stream
,
2035 struct lttng_consumer_local_data
*ctx
)
2038 struct ustctl_consumer_stream
*ustream
;
2043 ustream
= stream
->ustream
;
2046 * First, we are going to check if there is a new subbuffer available
2047 * before reading the stream wait_fd.
2049 /* Get the next subbuffer */
2050 ret
= ustctl_get_next_subbuf(ustream
);
2052 /* No more data found, flag the stream. */
2053 stream
->has_data
= 0;
2058 ret
= ustctl_put_subbuf(ustream
);
2061 /* This stream still has data. Flag it and wake up the data thread. */
2062 stream
->has_data
= 1;
2064 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !ctx
->has_wakeup
) {
2067 writelen
= lttng_pipe_write(ctx
->consumer_wakeup_pipe
, "!", 1);
2068 if (writelen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2073 /* The wake up pipe has been notified. */
2074 ctx
->has_wakeup
= 1;
2083 * Read subbuffer from the given stream.
2085 * Stream lock MUST be acquired.
2087 * Return 0 on success else a negative value.
2089 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
2090 struct lttng_consumer_local_data
*ctx
)
2092 unsigned long len
, subbuf_size
, padding
;
2093 int err
, write_index
= 1;
2095 struct ustctl_consumer_stream
*ustream
;
2096 struct ctf_packet_index index
;
2099 assert(stream
->ustream
);
2102 DBG("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
2105 /* Ease our life for what's next. */
2106 ustream
= stream
->ustream
;
2109 * We can consume the 1 byte written into the wait_fd by UST. Don't trigger
2110 * error if we cannot read this one byte (read returns 0), or if the error
2111 * is EAGAIN or EWOULDBLOCK.
2113 * This is only done when the stream is monitored by a thread, before the
2114 * flush is done after a hangup and if the stream is not flagged with data
2115 * since there might be nothing to consume in the wait fd but still have
2116 * data available flagged by the consumer wake up pipe.
2118 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !stream
->has_data
) {
2122 readlen
= lttng_read(stream
->wait_fd
, &dummy
, 1);
2123 if (readlen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2130 /* Get the next subbuffer */
2131 err
= ustctl_get_next_subbuf(ustream
);
2134 * Populate metadata info if the existing info has
2135 * already been read.
2137 if (stream
->metadata_flag
) {
2138 ret
= commit_one_metadata_packet(stream
);
2142 ustctl_flush_buffer(stream
->ustream
, 1);
2146 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
2148 * This is a debug message even for single-threaded consumer,
2149 * because poll() have more relaxed criterions than get subbuf,
2150 * so get_subbuf may fail for short race windows where poll()
2151 * would issue wakeups.
2153 DBG("Reserving sub buffer failed (everything is normal, "
2154 "it is due to concurrency) [ret: %d]", err
);
2157 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
2159 if (!stream
->metadata_flag
) {
2160 index
.offset
= htobe64(stream
->out_fd_offset
);
2161 ret
= get_index_values(&index
, ustream
);
2169 /* Get the full padded subbuffer size */
2170 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
2173 /* Get subbuffer data size (without padding) */
2174 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
2177 /* Make sure we don't get a subbuffer size bigger than the padded */
2178 assert(len
>= subbuf_size
);
2180 padding
= len
- subbuf_size
;
2181 /* write the subbuffer to the tracefile */
2182 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
, &index
);
2184 * The mmap operation should write subbuf_size amount of data when network
2185 * streaming or the full padding (len) size when we are _not_ streaming.
2187 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
2188 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
2190 * Display the error but continue processing to try to release the
2191 * subbuffer. This is a DBG statement since any unexpected kill or
2192 * signal, the application gets unregistered, relayd gets closed or
2193 * anything that affects the buffer lifetime will trigger this error.
2194 * So, for the sake of the user, don't print this error since it can
2195 * happen and it is OK with the code flow.
2197 DBG("Error writing to tracefile "
2198 "(ret: %ld != len: %lu != subbuf_size: %lu)",
2199 ret
, len
, subbuf_size
);
2202 err
= ustctl_put_next_subbuf(ustream
);
2206 * This will consumer the byte on the wait_fd if and only if there is not
2207 * next subbuffer to be acquired.
2209 if (!stream
->metadata_flag
) {
2210 ret
= notify_if_more_data(stream
, ctx
);
2216 /* Write index if needed. */
2221 if (stream
->chan
->live_timer_interval
&& !stream
->metadata_flag
) {
2223 * In live, block until all the metadata is sent.
2225 err
= consumer_stream_sync_metadata(ctx
, stream
->session_id
);
2231 assert(!stream
->metadata_flag
);
2232 err
= consumer_stream_write_index(stream
, &index
);
2242 * Called when a stream is created.
2244 * Return 0 on success or else a negative value.
2246 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
2252 /* Don't create anything if this is set for streaming. */
2253 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
) {
2254 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
2255 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
2256 stream
->uid
, stream
->gid
, NULL
);
2260 stream
->out_fd
= ret
;
2261 stream
->tracefile_size_current
= 0;
2263 if (!stream
->metadata_flag
) {
2264 ret
= index_create_file(stream
->chan
->pathname
,
2265 stream
->name
, stream
->uid
, stream
->gid
,
2266 stream
->chan
->tracefile_size
,
2267 stream
->tracefile_count_current
);
2271 stream
->index_fd
= ret
;
2281 * Check if data is still being extracted from the buffers for a specific
2282 * stream. Consumer data lock MUST be acquired before calling this function
2283 * and the stream lock.
2285 * Return 1 if the traced data are still getting read else 0 meaning that the
2286 * data is available for trace viewer reading.
2288 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
2293 assert(stream
->ustream
);
2295 DBG("UST consumer checking data pending");
2297 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
2302 if (stream
->chan
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
2303 uint64_t contiguous
, pushed
;
2305 /* Ease our life a bit. */
2306 contiguous
= stream
->chan
->metadata_cache
->contiguous
;
2307 pushed
= stream
->ust_metadata_pushed
;
2310 * We can simply check whether all contiguously available data
2311 * has been pushed to the ring buffer, since the push operation
2312 * is performed within get_next_subbuf(), and because both
2313 * get_next_subbuf() and put_next_subbuf() are issued atomically
2314 * thanks to the stream lock within
2315 * lttng_ustconsumer_read_subbuffer(). This basically means that
2316 * whetnever ust_metadata_pushed is incremented, the associated
2317 * metadata has been consumed from the metadata stream.
2319 DBG("UST consumer metadata pending check: contiguous %" PRIu64
" vs pushed %" PRIu64
,
2320 contiguous
, pushed
);
2321 assert(((int64_t) (contiguous
- pushed
)) >= 0);
2322 if ((contiguous
!= pushed
) ||
2323 (((int64_t) contiguous
- pushed
) > 0 || contiguous
== 0)) {
2324 ret
= 1; /* Data is pending */
2328 ret
= ustctl_get_next_subbuf(stream
->ustream
);
2331 * There is still data so let's put back this
2334 ret
= ustctl_put_subbuf(stream
->ustream
);
2336 ret
= 1; /* Data is pending */
2341 /* Data is NOT pending so ready to be read. */
2349 * Stop a given metadata channel timer if enabled and close the wait fd which
2350 * is the poll pipe of the metadata stream.
2352 * This MUST be called with the metadata channel acquired.
2354 void lttng_ustconsumer_close_metadata(struct lttng_consumer_channel
*metadata
)
2359 assert(metadata
->type
== CONSUMER_CHANNEL_TYPE_METADATA
);
2361 DBG("Closing metadata channel key %" PRIu64
, metadata
->key
);
2363 if (metadata
->switch_timer_enabled
== 1) {
2364 consumer_timer_switch_stop(metadata
);
2367 if (!metadata
->metadata_stream
) {
2372 * Closing write side so the thread monitoring the stream wakes up if any
2373 * and clean the metadata stream.
2375 if (metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] >= 0) {
2376 ret
= close(metadata
->metadata_stream
->ust_metadata_poll_pipe
[1]);
2378 PERROR("closing metadata pipe write side");
2380 metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] = -1;
2388 * Close every metadata stream wait fd of the metadata hash table. This
2389 * function MUST be used very carefully so not to run into a race between the
2390 * metadata thread handling streams and this function closing their wait fd.
2392 * For UST, this is used when the session daemon hangs up. Its the metadata
2393 * producer so calling this is safe because we are assured that no state change
2394 * can occur in the metadata thread for the streams in the hash table.
2396 void lttng_ustconsumer_close_all_metadata(struct lttng_ht
*metadata_ht
)
2398 struct lttng_ht_iter iter
;
2399 struct lttng_consumer_stream
*stream
;
2401 assert(metadata_ht
);
2402 assert(metadata_ht
->ht
);
2404 DBG("UST consumer closing all metadata streams");
2407 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
2410 health_code_update();
2412 pthread_mutex_lock(&stream
->chan
->lock
);
2413 lttng_ustconsumer_close_metadata(stream
->chan
);
2414 pthread_mutex_unlock(&stream
->chan
->lock
);
2420 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
2424 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
2426 ERR("Unable to close wakeup fd");
2431 * Please refer to consumer-timer.c before adding any lock within this
2432 * function or any of its callees. Timers have a very strict locking
2433 * semantic with respect to teardown. Failure to respect this semantic
2434 * introduces deadlocks.
2436 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
2437 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
2439 struct lttcomm_metadata_request_msg request
;
2440 struct lttcomm_consumer_msg msg
;
2441 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
2442 uint64_t len
, key
, offset
;
2446 assert(channel
->metadata_cache
);
2448 memset(&request
, 0, sizeof(request
));
2450 /* send the metadata request to sessiond */
2451 switch (consumer_data
.type
) {
2452 case LTTNG_CONSUMER64_UST
:
2453 request
.bits_per_long
= 64;
2455 case LTTNG_CONSUMER32_UST
:
2456 request
.bits_per_long
= 32;
2459 request
.bits_per_long
= 0;
2463 request
.session_id
= channel
->session_id
;
2464 request
.session_id_per_pid
= channel
->session_id_per_pid
;
2466 * Request the application UID here so the metadata of that application can
2467 * be sent back. The channel UID corresponds to the user UID of the session
2468 * used for the rights on the stream file(s).
2470 request
.uid
= channel
->ust_app_uid
;
2471 request
.key
= channel
->key
;
2473 DBG("Sending metadata request to sessiond, session id %" PRIu64
2474 ", per-pid %" PRIu64
", app UID %u and channek key %" PRIu64
,
2475 request
.session_id
, request
.session_id_per_pid
, request
.uid
,
2478 pthread_mutex_lock(&ctx
->metadata_socket_lock
);
2480 health_code_update();
2482 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
2485 ERR("Asking metadata to sessiond");
2489 health_code_update();
2491 /* Receive the metadata from sessiond */
2492 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
2494 if (ret
!= sizeof(msg
)) {
2495 DBG("Consumer received unexpected message size %d (expects %zu)",
2497 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
2499 * The ret value might 0 meaning an orderly shutdown but this is ok
2500 * since the caller handles this.
2505 health_code_update();
2507 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
2508 /* No registry found */
2509 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2513 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
2514 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
2519 len
= msg
.u
.push_metadata
.len
;
2520 key
= msg
.u
.push_metadata
.key
;
2521 offset
= msg
.u
.push_metadata
.target_offset
;
2523 assert(key
== channel
->key
);
2525 DBG("No new metadata to receive for key %" PRIu64
, key
);
2528 health_code_update();
2530 /* Tell session daemon we are ready to receive the metadata. */
2531 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2532 LTTCOMM_CONSUMERD_SUCCESS
);
2533 if (ret
< 0 || len
== 0) {
2535 * Somehow, the session daemon is not responding anymore or there is
2536 * nothing to receive.
2541 health_code_update();
2543 ret
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
2544 key
, offset
, len
, channel
, timer
, wait
);
2547 * Only send the status msg if the sessiond is alive meaning a positive
2550 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret
);
2555 health_code_update();
2557 pthread_mutex_unlock(&ctx
->metadata_socket_lock
);
2562 * Return the ustctl call for the get stream id.
2564 int lttng_ustconsumer_get_stream_id(struct lttng_consumer_stream
*stream
,
2565 uint64_t *stream_id
)
2570 return ustctl_get_stream_id(stream
->ustream
, stream_id
);