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
);
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 net_seq_idx
= -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 (net_seq_idx
== -1ULL) {
583 net_seq_idx
= stream
->net_seq_idx
;
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 ustctl_flush_buffer(stream
->ustream
, 1);
779 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
780 * RCU read side lock MUST be acquired before calling this function.
782 * Return 0 on success else an LTTng error code.
784 static int close_metadata(uint64_t chan_key
)
787 struct lttng_consumer_channel
*channel
;
789 DBG("UST consumer close metadata key %" PRIu64
, chan_key
);
791 channel
= consumer_find_channel(chan_key
);
794 * This is possible if the metadata thread has issue a delete because
795 * the endpoint point of the stream hung up. There is no way the
796 * session daemon can know about it thus use a DBG instead of an actual
799 DBG("UST consumer close metadata %" PRIu64
" not found", chan_key
);
800 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
804 pthread_mutex_lock(&consumer_data
.lock
);
805 pthread_mutex_lock(&channel
->lock
);
807 if (cds_lfht_is_node_deleted(&channel
->node
.node
)) {
811 lttng_ustconsumer_close_metadata(channel
);
814 pthread_mutex_unlock(&channel
->lock
);
815 pthread_mutex_unlock(&consumer_data
.lock
);
821 * RCU read side lock MUST be acquired before calling this function.
823 * Return 0 on success else an LTTng error code.
825 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
828 struct lttng_consumer_channel
*metadata
;
830 DBG("UST consumer setup metadata key %" PRIu64
, key
);
832 metadata
= consumer_find_channel(key
);
834 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
835 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
840 * In no monitor mode, the metadata channel has no stream(s) so skip the
841 * ownership transfer to the metadata thread.
843 if (!metadata
->monitor
) {
844 DBG("Metadata channel in no monitor");
850 * Send metadata stream to relayd if one available. Availability is
851 * known if the stream is still in the list of the channel.
853 if (cds_list_empty(&metadata
->streams
.head
)) {
854 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
855 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
856 goto error_no_stream
;
859 /* Send metadata stream to relayd if needed. */
860 if (metadata
->metadata_stream
->net_seq_idx
!= (uint64_t) -1ULL) {
861 ret
= consumer_send_relayd_stream(metadata
->metadata_stream
,
864 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
867 ret
= consumer_send_relayd_streams_sent(
868 metadata
->metadata_stream
->net_seq_idx
);
870 ret
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
875 ret
= send_streams_to_thread(metadata
, ctx
);
878 * If we are unable to send the stream to the thread, there is
879 * a big problem so just stop everything.
881 ret
= LTTCOMM_CONSUMERD_FATAL
;
884 /* List MUST be empty after or else it could be reused. */
885 assert(cds_list_empty(&metadata
->streams
.head
));
892 * Delete metadata channel on error. At this point, the metadata stream can
893 * NOT be monitored by the metadata thread thus having the guarantee that
894 * the stream is still in the local stream list of the channel. This call
895 * will make sure to clean that list.
897 consumer_stream_destroy(metadata
->metadata_stream
, NULL
);
898 cds_list_del(&metadata
->metadata_stream
->send_node
);
899 metadata
->metadata_stream
= NULL
;
906 * Snapshot the whole metadata.
908 * Returns 0 on success, < 0 on error
910 static int snapshot_metadata(uint64_t key
, char *path
, uint64_t relayd_id
,
911 struct lttng_consumer_local_data
*ctx
)
914 struct lttng_consumer_channel
*metadata_channel
;
915 struct lttng_consumer_stream
*metadata_stream
;
920 DBG("UST consumer snapshot metadata with key %" PRIu64
" at path %s",
925 metadata_channel
= consumer_find_channel(key
);
926 if (!metadata_channel
) {
927 ERR("UST snapshot metadata channel not found for key %" PRIu64
,
932 assert(!metadata_channel
->monitor
);
934 health_code_update();
937 * Ask the sessiond if we have new metadata waiting and update the
938 * consumer metadata cache.
940 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata_channel
, 0, 1);
945 health_code_update();
948 * The metadata stream is NOT created in no monitor mode when the channel
949 * is created on a sessiond ask channel command.
951 ret
= create_ust_streams(metadata_channel
, ctx
);
956 metadata_stream
= metadata_channel
->metadata_stream
;
957 assert(metadata_stream
);
959 if (relayd_id
!= (uint64_t) -1ULL) {
960 metadata_stream
->net_seq_idx
= relayd_id
;
961 ret
= consumer_send_relayd_stream(metadata_stream
, path
);
966 ret
= utils_create_stream_file(path
, metadata_stream
->name
,
967 metadata_stream
->chan
->tracefile_size
,
968 metadata_stream
->tracefile_count_current
,
969 metadata_stream
->uid
, metadata_stream
->gid
, NULL
);
973 metadata_stream
->out_fd
= ret
;
974 metadata_stream
->tracefile_size_current
= 0;
978 health_code_update();
980 ret
= lttng_consumer_read_subbuffer(metadata_stream
, ctx
);
988 * Clean up the stream completly because the next snapshot will use a new
991 consumer_stream_destroy(metadata_stream
, NULL
);
992 cds_list_del(&metadata_stream
->send_node
);
993 metadata_channel
->metadata_stream
= NULL
;
1001 * Take a snapshot of all the stream of a channel.
1003 * Returns 0 on success, < 0 on error
1005 static int snapshot_channel(uint64_t key
, char *path
, uint64_t relayd_id
,
1006 uint64_t nb_packets_per_stream
, struct lttng_consumer_local_data
*ctx
)
1009 unsigned use_relayd
= 0;
1010 unsigned long consumed_pos
, produced_pos
;
1011 struct lttng_consumer_channel
*channel
;
1012 struct lttng_consumer_stream
*stream
;
1019 if (relayd_id
!= (uint64_t) -1ULL) {
1023 channel
= consumer_find_channel(key
);
1025 ERR("UST snapshot channel not found for key %" PRIu64
, key
);
1029 assert(!channel
->monitor
);
1030 DBG("UST consumer snapshot channel %" PRIu64
, key
);
1032 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
1034 health_code_update();
1036 /* Lock stream because we are about to change its state. */
1037 pthread_mutex_lock(&stream
->lock
);
1038 stream
->net_seq_idx
= relayd_id
;
1041 ret
= consumer_send_relayd_stream(stream
, path
);
1046 ret
= utils_create_stream_file(path
, stream
->name
,
1047 stream
->chan
->tracefile_size
,
1048 stream
->tracefile_count_current
,
1049 stream
->uid
, stream
->gid
, NULL
);
1053 stream
->out_fd
= ret
;
1054 stream
->tracefile_size_current
= 0;
1056 DBG("UST consumer snapshot stream %s/%s (%" PRIu64
")", path
,
1057 stream
->name
, stream
->key
);
1059 if (relayd_id
!= -1ULL) {
1060 ret
= consumer_send_relayd_streams_sent(relayd_id
);
1066 ustctl_flush_buffer(stream
->ustream
, 1);
1068 ret
= lttng_ustconsumer_take_snapshot(stream
);
1070 ERR("Taking UST snapshot");
1074 ret
= lttng_ustconsumer_get_produced_snapshot(stream
, &produced_pos
);
1076 ERR("Produced UST snapshot position");
1080 ret
= lttng_ustconsumer_get_consumed_snapshot(stream
, &consumed_pos
);
1082 ERR("Consumerd UST snapshot position");
1087 * The original value is sent back if max stream size is larger than
1088 * the possible size of the snapshot. Also, we assume that the session
1089 * daemon should never send a maximum stream size that is lower than
1092 consumed_pos
= consumer_get_consume_start_pos(consumed_pos
,
1093 produced_pos
, nb_packets_per_stream
,
1094 stream
->max_sb_size
);
1096 while (consumed_pos
< produced_pos
) {
1098 unsigned long len
, padded_len
;
1100 health_code_update();
1102 DBG("UST consumer taking snapshot at pos %lu", consumed_pos
);
1104 ret
= ustctl_get_subbuf(stream
->ustream
, &consumed_pos
);
1106 if (ret
!= -EAGAIN
) {
1107 PERROR("ustctl_get_subbuf snapshot");
1108 goto error_close_stream
;
1110 DBG("UST consumer get subbuf failed. Skipping it.");
1111 consumed_pos
+= stream
->max_sb_size
;
1115 ret
= ustctl_get_subbuf_size(stream
->ustream
, &len
);
1117 ERR("Snapshot ustctl_get_subbuf_size");
1118 goto error_put_subbuf
;
1121 ret
= ustctl_get_padded_subbuf_size(stream
->ustream
, &padded_len
);
1123 ERR("Snapshot ustctl_get_padded_subbuf_size");
1124 goto error_put_subbuf
;
1127 read_len
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, len
,
1128 padded_len
- len
, NULL
);
1130 if (read_len
!= len
) {
1132 goto error_put_subbuf
;
1135 if (read_len
!= padded_len
) {
1137 goto error_put_subbuf
;
1141 ret
= ustctl_put_subbuf(stream
->ustream
);
1143 ERR("Snapshot ustctl_put_subbuf");
1144 goto error_close_stream
;
1146 consumed_pos
+= stream
->max_sb_size
;
1149 /* Simply close the stream so we can use it on the next snapshot. */
1150 consumer_stream_close(stream
);
1151 pthread_mutex_unlock(&stream
->lock
);
1158 if (ustctl_put_subbuf(stream
->ustream
) < 0) {
1159 ERR("Snapshot ustctl_put_subbuf");
1162 consumer_stream_close(stream
);
1164 pthread_mutex_unlock(&stream
->lock
);
1171 * Receive the metadata updates from the sessiond.
1173 int lttng_ustconsumer_recv_metadata(int sock
, uint64_t key
, uint64_t offset
,
1174 uint64_t len
, struct lttng_consumer_channel
*channel
,
1175 int timer
, int wait
)
1177 int ret
, ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1180 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
, len
);
1182 metadata_str
= zmalloc(len
* sizeof(char));
1183 if (!metadata_str
) {
1184 PERROR("zmalloc metadata string");
1185 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
1189 health_code_update();
1191 /* Receive metadata string. */
1192 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
1194 /* Session daemon is dead so return gracefully. */
1199 health_code_update();
1201 pthread_mutex_lock(&channel
->metadata_cache
->lock
);
1202 ret
= consumer_metadata_cache_write(channel
, offset
, len
, metadata_str
);
1204 /* Unable to handle metadata. Notify session daemon. */
1205 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1207 * Skip metadata flush on write error since the offset and len might
1208 * not have been updated which could create an infinite loop below when
1209 * waiting for the metadata cache to be flushed.
1211 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1214 pthread_mutex_unlock(&channel
->metadata_cache
->lock
);
1219 while (consumer_metadata_cache_flushed(channel
, offset
+ len
, timer
)) {
1220 DBG("Waiting for metadata to be flushed");
1222 health_code_update();
1224 usleep(DEFAULT_METADATA_AVAILABILITY_WAIT_TIME
);
1234 * Receive command from session daemon and process it.
1236 * Return 1 on success else a negative value or 0.
1238 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
1239 int sock
, struct pollfd
*consumer_sockpoll
)
1242 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
1243 struct lttcomm_consumer_msg msg
;
1244 struct lttng_consumer_channel
*channel
= NULL
;
1246 health_code_update();
1248 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
1249 if (ret
!= sizeof(msg
)) {
1250 DBG("Consumer received unexpected message size %zd (expects %zu)",
1253 * The ret value might 0 meaning an orderly shutdown but this is ok
1254 * since the caller handles this.
1257 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
1263 health_code_update();
1266 assert(msg
.cmd_type
!= LTTNG_CONSUMER_STOP
);
1268 health_code_update();
1270 /* relayd needs RCU read-side lock */
1273 switch (msg
.cmd_type
) {
1274 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
1276 /* Session daemon status message are handled in the following call. */
1277 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
1278 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
1279 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
,
1280 msg
.u
.relayd_sock
.relayd_session_id
);
1283 case LTTNG_CONSUMER_DESTROY_RELAYD
:
1285 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
1286 struct consumer_relayd_sock_pair
*relayd
;
1288 DBG("UST consumer destroying relayd %" PRIu64
, index
);
1290 /* Get relayd reference if exists. */
1291 relayd
= consumer_find_relayd(index
);
1292 if (relayd
== NULL
) {
1293 DBG("Unable to find relayd %" PRIu64
, index
);
1294 ret_code
= LTTCOMM_CONSUMERD_RELAYD_FAIL
;
1298 * Each relayd socket pair has a refcount of stream attached to it
1299 * which tells if the relayd is still active or not depending on the
1302 * This will set the destroy flag of the relayd object and destroy it
1303 * if the refcount reaches zero when called.
1305 * The destroy can happen either here or when a stream fd hangs up.
1308 consumer_flag_relayd_for_destroy(relayd
);
1311 goto end_msg_sessiond
;
1313 case LTTNG_CONSUMER_UPDATE_STREAM
:
1318 case LTTNG_CONSUMER_DATA_PENDING
:
1320 int ret
, is_data_pending
;
1321 uint64_t id
= msg
.u
.data_pending
.session_id
;
1323 DBG("UST consumer data pending command for id %" PRIu64
, id
);
1325 is_data_pending
= consumer_data_pending(id
);
1327 /* Send back returned value to session daemon */
1328 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
1329 sizeof(is_data_pending
));
1331 DBG("Error when sending the data pending ret code: %d", ret
);
1336 * No need to send back a status message since the data pending
1337 * returned value is the response.
1341 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
1344 struct ustctl_consumer_channel_attr attr
;
1346 /* Create a plain object and reserve a channel key. */
1347 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
1348 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
1349 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
1350 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
1351 (enum lttng_event_output
) msg
.u
.ask_channel
.output
,
1352 msg
.u
.ask_channel
.tracefile_size
,
1353 msg
.u
.ask_channel
.tracefile_count
,
1354 msg
.u
.ask_channel
.session_id_per_pid
,
1355 msg
.u
.ask_channel
.monitor
,
1356 msg
.u
.ask_channel
.live_timer_interval
,
1357 msg
.u
.ask_channel
.root_shm_path
,
1358 msg
.u
.ask_channel
.shm_path
);
1360 goto end_channel_error
;
1364 * Assign UST application UID to the channel. This value is ignored for
1365 * per PID buffers. This is specific to UST thus setting this after the
1368 channel
->ust_app_uid
= msg
.u
.ask_channel
.ust_app_uid
;
1370 /* Build channel attributes from received message. */
1371 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
1372 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
1373 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
1374 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
1375 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
1376 attr
.chan_id
= msg
.u
.ask_channel
.chan_id
;
1377 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
1379 /* Match channel buffer type to the UST abi. */
1380 switch (msg
.u
.ask_channel
.output
) {
1381 case LTTNG_EVENT_MMAP
:
1383 attr
.output
= LTTNG_UST_MMAP
;
1387 /* Translate and save channel type. */
1388 switch (msg
.u
.ask_channel
.type
) {
1389 case LTTNG_UST_CHAN_PER_CPU
:
1390 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
1391 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
1393 * Set refcount to 1 for owner. Below, we will
1394 * pass ownership to the
1395 * consumer_thread_channel_poll() thread.
1397 channel
->refcount
= 1;
1399 case LTTNG_UST_CHAN_METADATA
:
1400 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
1401 attr
.type
= LTTNG_UST_CHAN_METADATA
;
1408 health_code_update();
1410 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
1412 goto end_channel_error
;
1415 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1416 ret
= consumer_metadata_cache_allocate(channel
);
1418 ERR("Allocating metadata cache");
1419 goto end_channel_error
;
1421 consumer_timer_switch_start(channel
, attr
.switch_timer_interval
);
1422 attr
.switch_timer_interval
= 0;
1424 consumer_timer_live_start(channel
,
1425 msg
.u
.ask_channel
.live_timer_interval
);
1428 health_code_update();
1431 * Add the channel to the internal state AFTER all streams were created
1432 * and successfully sent to session daemon. This way, all streams must
1433 * be ready before this channel is visible to the threads.
1434 * If add_channel succeeds, ownership of the channel is
1435 * passed to consumer_thread_channel_poll().
1437 ret
= add_channel(channel
, ctx
);
1439 if (msg
.u
.ask_channel
.type
== LTTNG_UST_CHAN_METADATA
) {
1440 if (channel
->switch_timer_enabled
== 1) {
1441 consumer_timer_switch_stop(channel
);
1443 consumer_metadata_cache_destroy(channel
);
1445 if (channel
->live_timer_enabled
== 1) {
1446 consumer_timer_live_stop(channel
);
1448 goto end_channel_error
;
1451 health_code_update();
1454 * Channel and streams are now created. Inform the session daemon that
1455 * everything went well and should wait to receive the channel and
1456 * streams with ustctl API.
1458 ret
= consumer_send_status_channel(sock
, channel
);
1461 * There is probably a problem on the socket.
1468 case LTTNG_CONSUMER_GET_CHANNEL
:
1470 int ret
, relayd_err
= 0;
1471 uint64_t key
= msg
.u
.get_channel
.key
;
1472 struct lttng_consumer_channel
*channel
;
1474 channel
= consumer_find_channel(key
);
1476 ERR("UST consumer get channel key %" PRIu64
" not found", key
);
1477 ret_code
= LTTCOMM_CONSUMERD_CHAN_NOT_FOUND
;
1478 goto end_msg_sessiond
;
1481 health_code_update();
1483 /* Send everything to sessiond. */
1484 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
1488 * We were unable to send to the relayd the stream so avoid
1489 * sending back a fatal error to the thread since this is OK
1490 * and the consumer can continue its work. The above call
1491 * has sent the error status message to the sessiond.
1496 * The communicaton was broken hence there is a bad state between
1497 * the consumer and sessiond so stop everything.
1502 health_code_update();
1505 * In no monitor mode, the streams ownership is kept inside the channel
1506 * so don't send them to the data thread.
1508 if (!channel
->monitor
) {
1509 goto end_msg_sessiond
;
1512 ret
= send_streams_to_thread(channel
, ctx
);
1515 * If we are unable to send the stream to the thread, there is
1516 * a big problem so just stop everything.
1520 /* List MUST be empty after or else it could be reused. */
1521 assert(cds_list_empty(&channel
->streams
.head
));
1522 goto end_msg_sessiond
;
1524 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
1526 uint64_t key
= msg
.u
.destroy_channel
.key
;
1529 * Only called if streams have not been sent to stream
1530 * manager thread. However, channel has been sent to
1531 * channel manager thread.
1533 notify_thread_del_channel(ctx
, key
);
1534 goto end_msg_sessiond
;
1536 case LTTNG_CONSUMER_CLOSE_METADATA
:
1540 ret
= close_metadata(msg
.u
.close_metadata
.key
);
1545 goto end_msg_sessiond
;
1547 case LTTNG_CONSUMER_FLUSH_CHANNEL
:
1551 ret
= flush_channel(msg
.u
.flush_channel
.key
);
1556 goto end_msg_sessiond
;
1558 case LTTNG_CONSUMER_PUSH_METADATA
:
1561 uint64_t len
= msg
.u
.push_metadata
.len
;
1562 uint64_t key
= msg
.u
.push_metadata
.key
;
1563 uint64_t offset
= msg
.u
.push_metadata
.target_offset
;
1564 struct lttng_consumer_channel
*channel
;
1566 DBG("UST consumer push metadata key %" PRIu64
" of len %" PRIu64
, key
,
1569 channel
= consumer_find_channel(key
);
1572 * This is possible if the metadata creation on the consumer side
1573 * is in flight vis-a-vis a concurrent push metadata from the
1574 * session daemon. Simply return that the channel failed and the
1575 * session daemon will handle that message correctly considering
1576 * that this race is acceptable thus the DBG() statement here.
1578 DBG("UST consumer push metadata %" PRIu64
" not found", key
);
1579 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1580 goto end_msg_sessiond
;
1583 health_code_update();
1585 /* Tell session daemon we are ready to receive the metadata. */
1586 ret
= consumer_send_status_msg(sock
, LTTCOMM_CONSUMERD_SUCCESS
);
1588 /* Somehow, the session daemon is not responding anymore. */
1592 health_code_update();
1594 /* Wait for more data. */
1595 health_poll_entry();
1596 ret
= lttng_consumer_poll_socket(consumer_sockpoll
);
1602 health_code_update();
1604 ret
= lttng_ustconsumer_recv_metadata(sock
, key
, offset
,
1605 len
, channel
, 0, 1);
1607 /* error receiving from sessiond */
1611 goto end_msg_sessiond
;
1614 case LTTNG_CONSUMER_SETUP_METADATA
:
1618 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
1622 goto end_msg_sessiond
;
1624 case LTTNG_CONSUMER_SNAPSHOT_CHANNEL
:
1626 if (msg
.u
.snapshot_channel
.metadata
) {
1627 ret
= snapshot_metadata(msg
.u
.snapshot_channel
.key
,
1628 msg
.u
.snapshot_channel
.pathname
,
1629 msg
.u
.snapshot_channel
.relayd_id
,
1632 ERR("Snapshot metadata failed");
1633 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
1636 ret
= snapshot_channel(msg
.u
.snapshot_channel
.key
,
1637 msg
.u
.snapshot_channel
.pathname
,
1638 msg
.u
.snapshot_channel
.relayd_id
,
1639 msg
.u
.snapshot_channel
.nb_packets_per_stream
,
1642 ERR("Snapshot channel failed");
1643 ret_code
= LTTCOMM_CONSUMERD_CHANNEL_FAIL
;
1647 health_code_update();
1648 ret
= consumer_send_status_msg(sock
, ret_code
);
1650 /* Somehow, the session daemon is not responding anymore. */
1653 health_code_update();
1663 health_code_update();
1666 * Return 1 to indicate success since the 0 value can be a socket
1667 * shutdown during the recv() or send() call.
1673 * The returned value here is not useful since either way we'll return 1 to
1674 * the caller because the session daemon socket management is done
1675 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
1677 ret
= consumer_send_status_msg(sock
, ret_code
);
1683 health_code_update();
1689 * Free channel here since no one has a reference to it. We don't
1690 * free after that because a stream can store this pointer.
1692 destroy_channel(channel
);
1694 /* We have to send a status channel message indicating an error. */
1695 ret
= consumer_send_status_channel(sock
, NULL
);
1697 /* Stop everything if session daemon can not be notified. */
1702 health_code_update();
1707 /* This will issue a consumer stop. */
1712 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1713 * compiled out, we isolate it in this library.
1715 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1719 assert(stream
->ustream
);
1721 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1725 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1726 * compiled out, we isolate it in this library.
1728 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1731 assert(stream
->ustream
);
1733 return ustctl_get_mmap_base(stream
->ustream
);
1737 * Take a snapshot for a specific fd
1739 * Returns 0 on success, < 0 on error
1741 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1744 assert(stream
->ustream
);
1746 return ustctl_snapshot(stream
->ustream
);
1750 * Get the produced position
1752 * Returns 0 on success, < 0 on error
1754 int lttng_ustconsumer_get_produced_snapshot(
1755 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1758 assert(stream
->ustream
);
1761 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1765 * Get the consumed position
1767 * Returns 0 on success, < 0 on error
1769 int lttng_ustconsumer_get_consumed_snapshot(
1770 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1773 assert(stream
->ustream
);
1776 return ustctl_snapshot_get_consumed(stream
->ustream
, pos
);
1779 void lttng_ustconsumer_flush_buffer(struct lttng_consumer_stream
*stream
,
1783 assert(stream
->ustream
);
1785 ustctl_flush_buffer(stream
->ustream
, producer
);
1788 int lttng_ustconsumer_get_current_timestamp(
1789 struct lttng_consumer_stream
*stream
, uint64_t *ts
)
1792 assert(stream
->ustream
);
1795 return ustctl_get_current_timestamp(stream
->ustream
, ts
);
1799 * Called when the stream signal the consumer that it has hang up.
1801 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1804 assert(stream
->ustream
);
1806 ustctl_flush_buffer(stream
->ustream
, 0);
1807 stream
->hangup_flush_done
= 1;
1810 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1815 assert(chan
->uchan
);
1817 if (chan
->switch_timer_enabled
== 1) {
1818 consumer_timer_switch_stop(chan
);
1820 consumer_metadata_cache_destroy(chan
);
1821 ustctl_destroy_channel(chan
->uchan
);
1822 for (i
= 0; i
< chan
->nr_stream_fds
; i
++) {
1825 ret
= close(chan
->stream_fds
[i
]);
1829 if (chan
->shm_path
[0]) {
1830 char shm_path
[PATH_MAX
];
1832 ret
= get_stream_shm_path(shm_path
, chan
->shm_path
, i
);
1834 ERR("Cannot get stream shm path");
1836 ret
= run_as_unlink(shm_path
, chan
->uid
, chan
->gid
);
1839 PERROR("unlink %s", shm_path
);
1843 free(chan
->stream_fds
);
1844 /* Try to rmdir all directories under shm_path root. */
1845 if (chan
->root_shm_path
[0]) {
1846 (void) run_as_recursive_rmdir(chan
->root_shm_path
,
1847 chan
->uid
, chan
->gid
);
1851 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
1854 assert(stream
->ustream
);
1856 if (stream
->chan
->switch_timer_enabled
== 1) {
1857 consumer_timer_switch_stop(stream
->chan
);
1859 ustctl_destroy_stream(stream
->ustream
);
1862 int lttng_ustconsumer_get_wakeup_fd(struct lttng_consumer_stream
*stream
)
1865 assert(stream
->ustream
);
1867 return ustctl_stream_get_wakeup_fd(stream
->ustream
);
1870 int lttng_ustconsumer_close_wakeup_fd(struct lttng_consumer_stream
*stream
)
1873 assert(stream
->ustream
);
1875 return ustctl_stream_close_wakeup_fd(stream
->ustream
);
1879 * Populate index values of a UST stream. Values are set in big endian order.
1881 * Return 0 on success or else a negative value.
1883 static int get_index_values(struct ctf_packet_index
*index
,
1884 struct ustctl_consumer_stream
*ustream
)
1888 ret
= ustctl_get_timestamp_begin(ustream
, &index
->timestamp_begin
);
1890 PERROR("ustctl_get_timestamp_begin");
1893 index
->timestamp_begin
= htobe64(index
->timestamp_begin
);
1895 ret
= ustctl_get_timestamp_end(ustream
, &index
->timestamp_end
);
1897 PERROR("ustctl_get_timestamp_end");
1900 index
->timestamp_end
= htobe64(index
->timestamp_end
);
1902 ret
= ustctl_get_events_discarded(ustream
, &index
->events_discarded
);
1904 PERROR("ustctl_get_events_discarded");
1907 index
->events_discarded
= htobe64(index
->events_discarded
);
1909 ret
= ustctl_get_content_size(ustream
, &index
->content_size
);
1911 PERROR("ustctl_get_content_size");
1914 index
->content_size
= htobe64(index
->content_size
);
1916 ret
= ustctl_get_packet_size(ustream
, &index
->packet_size
);
1918 PERROR("ustctl_get_packet_size");
1921 index
->packet_size
= htobe64(index
->packet_size
);
1923 ret
= ustctl_get_stream_id(ustream
, &index
->stream_id
);
1925 PERROR("ustctl_get_stream_id");
1928 index
->stream_id
= htobe64(index
->stream_id
);
1935 * Write up to one packet from the metadata cache to the channel.
1937 * Returns the number of bytes pushed in the cache, or a negative value
1941 int commit_one_metadata_packet(struct lttng_consumer_stream
*stream
)
1946 pthread_mutex_lock(&stream
->chan
->metadata_cache
->lock
);
1947 if (stream
->chan
->metadata_cache
->contiguous
1948 == stream
->ust_metadata_pushed
) {
1953 write_len
= ustctl_write_one_packet_to_channel(stream
->chan
->uchan
,
1954 &stream
->chan
->metadata_cache
->data
[stream
->ust_metadata_pushed
],
1955 stream
->chan
->metadata_cache
->contiguous
1956 - stream
->ust_metadata_pushed
);
1957 assert(write_len
!= 0);
1958 if (write_len
< 0) {
1959 ERR("Writing one metadata packet");
1963 stream
->ust_metadata_pushed
+= write_len
;
1965 assert(stream
->chan
->metadata_cache
->contiguous
>=
1966 stream
->ust_metadata_pushed
);
1970 pthread_mutex_unlock(&stream
->chan
->metadata_cache
->lock
);
1976 * Sync metadata meaning request them to the session daemon and snapshot to the
1977 * metadata thread can consumer them.
1979 * Metadata stream lock MUST be acquired.
1981 * Return 0 if new metadatda is available, EAGAIN if the metadata stream
1982 * is empty or a negative value on error.
1984 int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data
*ctx
,
1985 struct lttng_consumer_stream
*metadata
)
1994 * Request metadata from the sessiond, but don't wait for the flush
1995 * because we locked the metadata thread.
1997 ret
= lttng_ustconsumer_request_metadata(ctx
, metadata
->chan
, 0, 0);
2002 ret
= commit_one_metadata_packet(metadata
);
2005 } else if (ret
> 0) {
2009 ustctl_flush_buffer(metadata
->ustream
, 1);
2010 ret
= ustctl_snapshot(metadata
->ustream
);
2012 if (errno
!= EAGAIN
) {
2013 ERR("Sync metadata, taking UST snapshot");
2016 DBG("No new metadata when syncing them.");
2017 /* No new metadata, exit. */
2023 * After this flush, we still need to extract metadata.
2034 * Return 0 on success else a negative value.
2036 static int notify_if_more_data(struct lttng_consumer_stream
*stream
,
2037 struct lttng_consumer_local_data
*ctx
)
2040 struct ustctl_consumer_stream
*ustream
;
2045 ustream
= stream
->ustream
;
2048 * First, we are going to check if there is a new subbuffer available
2049 * before reading the stream wait_fd.
2051 /* Get the next subbuffer */
2052 ret
= ustctl_get_next_subbuf(ustream
);
2054 /* No more data found, flag the stream. */
2055 stream
->has_data
= 0;
2060 ret
= ustctl_put_subbuf(ustream
);
2063 /* This stream still has data. Flag it and wake up the data thread. */
2064 stream
->has_data
= 1;
2066 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !ctx
->has_wakeup
) {
2069 writelen
= lttng_pipe_write(ctx
->consumer_wakeup_pipe
, "!", 1);
2070 if (writelen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2075 /* The wake up pipe has been notified. */
2076 ctx
->has_wakeup
= 1;
2085 * Read subbuffer from the given stream.
2087 * Stream lock MUST be acquired.
2089 * Return 0 on success else a negative value.
2091 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
2092 struct lttng_consumer_local_data
*ctx
)
2094 unsigned long len
, subbuf_size
, padding
;
2095 int err
, write_index
= 1;
2097 struct ustctl_consumer_stream
*ustream
;
2098 struct ctf_packet_index index
;
2101 assert(stream
->ustream
);
2104 DBG("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
2107 /* Ease our life for what's next. */
2108 ustream
= stream
->ustream
;
2111 * We can consume the 1 byte written into the wait_fd by UST. Don't trigger
2112 * error if we cannot read this one byte (read returns 0), or if the error
2113 * is EAGAIN or EWOULDBLOCK.
2115 * This is only done when the stream is monitored by a thread, before the
2116 * flush is done after a hangup and if the stream is not flagged with data
2117 * since there might be nothing to consume in the wait fd but still have
2118 * data available flagged by the consumer wake up pipe.
2120 if (stream
->monitor
&& !stream
->hangup_flush_done
&& !stream
->has_data
) {
2124 readlen
= lttng_read(stream
->wait_fd
, &dummy
, 1);
2125 if (readlen
< 0 && errno
!= EAGAIN
&& errno
!= EWOULDBLOCK
) {
2132 /* Get the next subbuffer */
2133 err
= ustctl_get_next_subbuf(ustream
);
2136 * Populate metadata info if the existing info has
2137 * already been read.
2139 if (stream
->metadata_flag
) {
2140 ret
= commit_one_metadata_packet(stream
);
2144 ustctl_flush_buffer(stream
->ustream
, 1);
2148 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
2150 * This is a debug message even for single-threaded consumer,
2151 * because poll() have more relaxed criterions than get subbuf,
2152 * so get_subbuf may fail for short race windows where poll()
2153 * would issue wakeups.
2155 DBG("Reserving sub buffer failed (everything is normal, "
2156 "it is due to concurrency) [ret: %d]", err
);
2159 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
2161 if (!stream
->metadata_flag
) {
2162 index
.offset
= htobe64(stream
->out_fd_offset
);
2163 ret
= get_index_values(&index
, ustream
);
2171 /* Get the full padded subbuffer size */
2172 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
2175 /* Get subbuffer data size (without padding) */
2176 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
2179 /* Make sure we don't get a subbuffer size bigger than the padded */
2180 assert(len
>= subbuf_size
);
2182 padding
= len
- subbuf_size
;
2183 /* write the subbuffer to the tracefile */
2184 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
, &index
);
2186 * The mmap operation should write subbuf_size amount of data when network
2187 * streaming or the full padding (len) size when we are _not_ streaming.
2189 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
2190 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
2192 * Display the error but continue processing to try to release the
2193 * subbuffer. This is a DBG statement since any unexpected kill or
2194 * signal, the application gets unregistered, relayd gets closed or
2195 * anything that affects the buffer lifetime will trigger this error.
2196 * So, for the sake of the user, don't print this error since it can
2197 * happen and it is OK with the code flow.
2199 DBG("Error writing to tracefile "
2200 "(ret: %ld != len: %lu != subbuf_size: %lu)",
2201 ret
, len
, subbuf_size
);
2204 err
= ustctl_put_next_subbuf(ustream
);
2208 * This will consumer the byte on the wait_fd if and only if there is not
2209 * next subbuffer to be acquired.
2211 if (!stream
->metadata_flag
) {
2212 ret
= notify_if_more_data(stream
, ctx
);
2218 /* Write index if needed. */
2223 if (stream
->chan
->live_timer_interval
&& !stream
->metadata_flag
) {
2225 * In live, block until all the metadata is sent.
2227 err
= consumer_stream_sync_metadata(ctx
, stream
->session_id
);
2233 assert(!stream
->metadata_flag
);
2234 err
= consumer_stream_write_index(stream
, &index
);
2244 * Called when a stream is created.
2246 * Return 0 on success or else a negative value.
2248 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
2254 /* Don't create anything if this is set for streaming. */
2255 if (stream
->net_seq_idx
== (uint64_t) -1ULL && stream
->chan
->monitor
) {
2256 ret
= utils_create_stream_file(stream
->chan
->pathname
, stream
->name
,
2257 stream
->chan
->tracefile_size
, stream
->tracefile_count_current
,
2258 stream
->uid
, stream
->gid
, NULL
);
2262 stream
->out_fd
= ret
;
2263 stream
->tracefile_size_current
= 0;
2265 if (!stream
->metadata_flag
) {
2266 ret
= index_create_file(stream
->chan
->pathname
,
2267 stream
->name
, stream
->uid
, stream
->gid
,
2268 stream
->chan
->tracefile_size
,
2269 stream
->tracefile_count_current
);
2273 stream
->index_fd
= ret
;
2283 * Check if data is still being extracted from the buffers for a specific
2284 * stream. Consumer data lock MUST be acquired before calling this function
2285 * and the stream lock.
2287 * Return 1 if the traced data are still getting read else 0 meaning that the
2288 * data is available for trace viewer reading.
2290 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
2295 assert(stream
->ustream
);
2297 DBG("UST consumer checking data pending");
2299 if (stream
->endpoint_status
!= CONSUMER_ENDPOINT_ACTIVE
) {
2304 if (stream
->chan
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
2305 uint64_t contiguous
, pushed
;
2307 /* Ease our life a bit. */
2308 contiguous
= stream
->chan
->metadata_cache
->contiguous
;
2309 pushed
= stream
->ust_metadata_pushed
;
2312 * We can simply check whether all contiguously available data
2313 * has been pushed to the ring buffer, since the push operation
2314 * is performed within get_next_subbuf(), and because both
2315 * get_next_subbuf() and put_next_subbuf() are issued atomically
2316 * thanks to the stream lock within
2317 * lttng_ustconsumer_read_subbuffer(). This basically means that
2318 * whetnever ust_metadata_pushed is incremented, the associated
2319 * metadata has been consumed from the metadata stream.
2321 DBG("UST consumer metadata pending check: contiguous %" PRIu64
" vs pushed %" PRIu64
,
2322 contiguous
, pushed
);
2323 assert(((int64_t) (contiguous
- pushed
)) >= 0);
2324 if ((contiguous
!= pushed
) ||
2325 (((int64_t) contiguous
- pushed
) > 0 || contiguous
== 0)) {
2326 ret
= 1; /* Data is pending */
2330 ret
= ustctl_get_next_subbuf(stream
->ustream
);
2333 * There is still data so let's put back this
2336 ret
= ustctl_put_subbuf(stream
->ustream
);
2338 ret
= 1; /* Data is pending */
2343 /* Data is NOT pending so ready to be read. */
2351 * Stop a given metadata channel timer if enabled and close the wait fd which
2352 * is the poll pipe of the metadata stream.
2354 * This MUST be called with the metadata channel acquired.
2356 void lttng_ustconsumer_close_metadata(struct lttng_consumer_channel
*metadata
)
2361 assert(metadata
->type
== CONSUMER_CHANNEL_TYPE_METADATA
);
2363 DBG("Closing metadata channel key %" PRIu64
, metadata
->key
);
2365 if (metadata
->switch_timer_enabled
== 1) {
2366 consumer_timer_switch_stop(metadata
);
2369 if (!metadata
->metadata_stream
) {
2374 * Closing write side so the thread monitoring the stream wakes up if any
2375 * and clean the metadata stream.
2377 if (metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] >= 0) {
2378 ret
= close(metadata
->metadata_stream
->ust_metadata_poll_pipe
[1]);
2380 PERROR("closing metadata pipe write side");
2382 metadata
->metadata_stream
->ust_metadata_poll_pipe
[1] = -1;
2390 * Close every metadata stream wait fd of the metadata hash table. This
2391 * function MUST be used very carefully so not to run into a race between the
2392 * metadata thread handling streams and this function closing their wait fd.
2394 * For UST, this is used when the session daemon hangs up. Its the metadata
2395 * producer so calling this is safe because we are assured that no state change
2396 * can occur in the metadata thread for the streams in the hash table.
2398 void lttng_ustconsumer_close_all_metadata(struct lttng_ht
*metadata_ht
)
2400 struct lttng_ht_iter iter
;
2401 struct lttng_consumer_stream
*stream
;
2403 assert(metadata_ht
);
2404 assert(metadata_ht
->ht
);
2406 DBG("UST consumer closing all metadata streams");
2409 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
2412 health_code_update();
2414 pthread_mutex_lock(&stream
->chan
->lock
);
2415 lttng_ustconsumer_close_metadata(stream
->chan
);
2416 pthread_mutex_unlock(&stream
->chan
->lock
);
2422 void lttng_ustconsumer_close_stream_wakeup(struct lttng_consumer_stream
*stream
)
2426 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
2428 ERR("Unable to close wakeup fd");
2433 * Please refer to consumer-timer.c before adding any lock within this
2434 * function or any of its callees. Timers have a very strict locking
2435 * semantic with respect to teardown. Failure to respect this semantic
2436 * introduces deadlocks.
2438 int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data
*ctx
,
2439 struct lttng_consumer_channel
*channel
, int timer
, int wait
)
2441 struct lttcomm_metadata_request_msg request
;
2442 struct lttcomm_consumer_msg msg
;
2443 enum lttcomm_return_code ret_code
= LTTCOMM_CONSUMERD_SUCCESS
;
2444 uint64_t len
, key
, offset
;
2448 assert(channel
->metadata_cache
);
2450 memset(&request
, 0, sizeof(request
));
2452 /* send the metadata request to sessiond */
2453 switch (consumer_data
.type
) {
2454 case LTTNG_CONSUMER64_UST
:
2455 request
.bits_per_long
= 64;
2457 case LTTNG_CONSUMER32_UST
:
2458 request
.bits_per_long
= 32;
2461 request
.bits_per_long
= 0;
2465 request
.session_id
= channel
->session_id
;
2466 request
.session_id_per_pid
= channel
->session_id_per_pid
;
2468 * Request the application UID here so the metadata of that application can
2469 * be sent back. The channel UID corresponds to the user UID of the session
2470 * used for the rights on the stream file(s).
2472 request
.uid
= channel
->ust_app_uid
;
2473 request
.key
= channel
->key
;
2475 DBG("Sending metadata request to sessiond, session id %" PRIu64
2476 ", per-pid %" PRIu64
", app UID %u and channek key %" PRIu64
,
2477 request
.session_id
, request
.session_id_per_pid
, request
.uid
,
2480 pthread_mutex_lock(&ctx
->metadata_socket_lock
);
2482 health_code_update();
2484 ret
= lttcomm_send_unix_sock(ctx
->consumer_metadata_socket
, &request
,
2487 ERR("Asking metadata to sessiond");
2491 health_code_update();
2493 /* Receive the metadata from sessiond */
2494 ret
= lttcomm_recv_unix_sock(ctx
->consumer_metadata_socket
, &msg
,
2496 if (ret
!= sizeof(msg
)) {
2497 DBG("Consumer received unexpected message size %d (expects %zu)",
2499 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
2501 * The ret value might 0 meaning an orderly shutdown but this is ok
2502 * since the caller handles this.
2507 health_code_update();
2509 if (msg
.cmd_type
== LTTNG_ERR_UND
) {
2510 /* No registry found */
2511 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2515 } else if (msg
.cmd_type
!= LTTNG_CONSUMER_PUSH_METADATA
) {
2516 ERR("Unexpected cmd_type received %d", msg
.cmd_type
);
2521 len
= msg
.u
.push_metadata
.len
;
2522 key
= msg
.u
.push_metadata
.key
;
2523 offset
= msg
.u
.push_metadata
.target_offset
;
2525 assert(key
== channel
->key
);
2527 DBG("No new metadata to receive for key %" PRIu64
, key
);
2530 health_code_update();
2532 /* Tell session daemon we are ready to receive the metadata. */
2533 ret
= consumer_send_status_msg(ctx
->consumer_metadata_socket
,
2534 LTTCOMM_CONSUMERD_SUCCESS
);
2535 if (ret
< 0 || len
== 0) {
2537 * Somehow, the session daemon is not responding anymore or there is
2538 * nothing to receive.
2543 health_code_update();
2545 ret
= lttng_ustconsumer_recv_metadata(ctx
->consumer_metadata_socket
,
2546 key
, offset
, len
, channel
, timer
, wait
);
2549 * Only send the status msg if the sessiond is alive meaning a positive
2552 (void) consumer_send_status_msg(ctx
->consumer_metadata_socket
, ret
);
2557 health_code_update();
2559 pthread_mutex_unlock(&ctx
->metadata_socket_lock
);
2564 * Return the ustctl call for the get stream id.
2566 int lttng_ustconsumer_get_stream_id(struct lttng_consumer_stream
*stream
,
2567 uint64_t *stream_id
)
2572 return ustctl_get_stream_id(stream
->ustream
, stream_id
);