2 * Copyright (C) 2011 - Julien Desfossez <julien.desfossez@polymtl.ca>
3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2 only,
7 * as published by the Free Software Foundation.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
21 #include <lttng/ust-ctl.h>
27 #include <sys/socket.h>
29 #include <sys/types.h>
32 #include <urcu/list.h>
34 #include <common/common.h>
35 #include <common/sessiond-comm/sessiond-comm.h>
36 #include <common/relayd/relayd.h>
37 #include <common/compat/fcntl.h>
39 #include "ust-consumer.h"
41 extern struct lttng_consumer_global_data consumer_data
;
42 extern int consumer_poll_timeout
;
43 extern volatile int consumer_quit
;
46 * Free channel object and all streams associated with it. This MUST be used
47 * only and only if the channel has _NEVER_ been added to the global channel
50 static void destroy_channel(struct lttng_consumer_channel
*channel
)
52 struct lttng_consumer_stream
*stream
, *stmp
;
56 DBG("UST consumer cleaning stream list");
58 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
60 cds_list_del(&stream
->send_node
);
61 ustctl_destroy_stream(stream
->ustream
);
66 * If a channel is available meaning that was created before the streams
70 lttng_ustconsumer_del_channel(channel
);
76 * Add channel to internal consumer state.
78 * Returns 0 on success or else a negative value.
80 static int add_channel(struct lttng_consumer_channel
*channel
,
81 struct lttng_consumer_local_data
*ctx
)
88 if (ctx
->on_recv_channel
!= NULL
) {
89 ret
= ctx
->on_recv_channel(channel
);
91 ret
= consumer_add_channel(channel
);
93 /* Most likely an ENOMEM. */
94 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
98 ret
= consumer_add_channel(channel
);
101 DBG("UST consumer channel added (key: %" PRIu64
")", channel
->key
);
108 * Allocate and return a consumer channel object.
110 static struct lttng_consumer_channel
*allocate_channel(uint64_t session_id
,
111 const char *pathname
, const char *name
, uid_t uid
, gid_t gid
,
112 int relayd_id
, uint64_t key
, enum lttng_event_output output
)
117 return consumer_allocate_channel(key
, session_id
, pathname
, name
, uid
, gid
,
122 * Allocate and return a consumer stream object. If _alloc_ret is not NULL, the
123 * error value if applicable is set in it else it is kept untouched.
125 * Return NULL on error else the newly allocated stream object.
127 static struct lttng_consumer_stream
*allocate_stream(int cpu
, int key
,
128 struct lttng_consumer_channel
*channel
,
129 struct lttng_consumer_local_data
*ctx
, int *_alloc_ret
)
132 struct lttng_consumer_stream
*stream
= NULL
;
137 stream
= consumer_allocate_stream(channel
->key
,
139 LTTNG_CONSUMER_ACTIVE_STREAM
,
148 if (stream
== NULL
) {
152 * We could not find the channel. Can happen if cpu hotplug
153 * happens while tearing down.
155 DBG3("Could not find channel");
160 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_OUTFD_ERROR
);
166 stream
->chan
= channel
;
170 *_alloc_ret
= alloc_ret
;
176 * Send the given stream pointer to the corresponding thread.
178 * Returns 0 on success else a negative value.
180 static int send_stream_to_thread(struct lttng_consumer_stream
*stream
,
181 struct lttng_consumer_local_data
*ctx
)
183 int ret
, stream_pipe
;
185 /* Get the right pipe where the stream will be sent. */
186 if (stream
->metadata_flag
) {
187 stream_pipe
= ctx
->consumer_metadata_pipe
[1];
189 stream_pipe
= ctx
->consumer_data_pipe
[1];
193 ret
= write(stream_pipe
, &stream
, sizeof(stream
));
194 } while (ret
< 0 && errno
== EINTR
);
196 PERROR("Consumer write %s stream to pipe %d",
197 stream
->metadata_flag
? "metadata" : "data", stream_pipe
);
204 * Search for a relayd object related to the stream. If found, send the stream
207 * On success, returns 0 else a negative value.
209 static int send_stream_to_relayd(struct lttng_consumer_stream
*stream
)
212 struct consumer_relayd_sock_pair
*relayd
;
216 relayd
= consumer_find_relayd(stream
->net_seq_idx
);
217 if (relayd
!= NULL
) {
218 pthread_mutex_lock(&relayd
->ctrl_sock_mutex
);
219 /* Add stream on the relayd */
220 ret
= relayd_add_stream(&relayd
->control_sock
, stream
->name
,
221 stream
->chan
->pathname
, &stream
->relayd_stream_id
);
222 pthread_mutex_unlock(&relayd
->ctrl_sock_mutex
);
226 } else if (stream
->net_seq_idx
!= (uint64_t) -1ULL) {
227 ERR("Network sequence index %" PRIu64
" unknown. Not adding stream.",
228 stream
->net_seq_idx
);
238 * Create streams for the given channel using liblttng-ust-ctl.
240 * Return 0 on success else a negative value.
242 static int create_ust_streams(struct lttng_consumer_channel
*channel
,
243 struct lttng_consumer_local_data
*ctx
)
246 struct ustctl_consumer_stream
*ustream
;
247 struct lttng_consumer_stream
*stream
;
253 * While a stream is available from ustctl. When NULL is returned, we've
254 * reached the end of the possible stream for the channel.
256 while ((ustream
= ustctl_create_stream(channel
->uchan
, cpu
))) {
259 wait_fd
= ustctl_stream_get_wait_fd(ustream
);
261 /* Allocate consumer stream object. */
262 stream
= allocate_stream(cpu
, wait_fd
, channel
, ctx
, &ret
);
266 stream
->ustream
= ustream
;
268 * Store it so we can save multiple function calls afterwards since
269 * this value is used heavily in the stream threads. This is UST
270 * specific so this is why it's done after allocation.
272 stream
->wait_fd
= wait_fd
;
275 * Order is important this is why a list is used. On error, the caller
276 * should clean this list.
278 cds_list_add_tail(&stream
->send_node
, &channel
->streams
.head
);
280 ret
= ustctl_get_max_subbuf_size(stream
->ustream
,
281 &stream
->max_sb_size
);
283 ERR("ustctl_get_max_subbuf_size failed for stream %s",
288 /* Do actions once stream has been received. */
289 if (ctx
->on_recv_stream
) {
290 ret
= ctx
->on_recv_stream(stream
);
296 DBG("UST consumer add stream %s (key: %" PRIu64
") with relayd id %" PRIu64
,
297 stream
->name
, stream
->key
, stream
->relayd_stream_id
);
299 /* Set next CPU stream. */
300 channel
->streams
.count
= ++cpu
;
302 /* Keep stream reference when creating metadata. */
303 if (channel
->type
== CONSUMER_CHANNEL_TYPE_METADATA
) {
304 channel
->metadata_stream
= stream
;
316 * Create an UST channel with the given attributes and send it to the session
317 * daemon using the ust ctl API.
319 * Return 0 on success or else a negative value.
321 static int create_ust_channel(struct ustctl_consumer_channel_attr
*attr
,
322 struct ustctl_consumer_channel
**chanp
)
325 struct ustctl_consumer_channel
*channel
;
330 DBG3("Creating channel to ustctl with attr: [overwrite: %d, "
331 "subbuf_size: %" PRIu64
", num_subbuf: %" PRIu64
", "
332 "switch_timer_interval: %u, read_timer_interval: %u, "
333 "output: %d, type: %d", attr
->overwrite
, attr
->subbuf_size
,
334 attr
->num_subbuf
, attr
->switch_timer_interval
,
335 attr
->read_timer_interval
, attr
->output
, attr
->type
);
337 channel
= ustctl_create_channel(attr
);
352 * Send a single given stream to the session daemon using the sock.
354 * Return 0 on success else a negative value.
356 static int send_sessiond_stream(int sock
, struct lttng_consumer_stream
*stream
)
363 DBG2("UST consumer sending stream %" PRIu64
" to sessiond", stream
->key
);
365 /* Send stream to session daemon. */
366 ret
= ustctl_send_stream_to_sessiond(sock
, stream
->ustream
);
371 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
381 * Send channel to sessiond.
383 * Return 0 on success or else a negative value.
385 static int send_sessiond_channel(int sock
,
386 struct lttng_consumer_channel
*channel
,
387 struct lttng_consumer_local_data
*ctx
, int *relayd_error
)
390 struct lttng_consumer_stream
*stream
;
396 DBG("UST consumer sending channel %s to sessiond", channel
->name
);
398 /* Send channel to sessiond. */
399 ret
= ustctl_send_channel_to_sessiond(sock
, channel
->uchan
);
404 /* The channel was sent successfully to the sessiond at this point. */
405 cds_list_for_each_entry(stream
, &channel
->streams
.head
, send_node
) {
406 /* Try to send the stream to the relayd if one is available. */
407 ret
= send_stream_to_relayd(stream
);
410 * Flag that the relayd was the problem here probably due to a
411 * communicaton error on the socket.
419 /* Send stream to session daemon. */
420 ret
= send_sessiond_stream(sock
, stream
);
426 /* Tell sessiond there is no more stream. */
427 ret
= ustctl_send_stream_to_sessiond(sock
, NULL
);
432 DBG("UST consumer NULL stream sent to sessiond");
441 * Creates a channel and streams and add the channel it to the channel internal
442 * state. The created stream must ONLY be sent once the GET_CHANNEL command is
445 * Return 0 on success or else, a negative value is returned and the channel
446 * MUST be destroyed by consumer_del_channel().
448 static int ask_channel(struct lttng_consumer_local_data
*ctx
, int sock
,
449 struct lttng_consumer_channel
*channel
,
450 struct ustctl_consumer_channel_attr
*attr
)
459 * This value is still used by the kernel consumer since for the kernel,
460 * the stream ownership is not IN the consumer so we need to have the
461 * number of left stream that needs to be initialized so we can know when
462 * to delete the channel (see consumer.c).
464 * As for the user space tracer now, the consumer creates and sends the
465 * stream to the session daemon which only sends them to the application
466 * once every stream of a channel is received making this value useless
467 * because we they will be added to the poll thread before the application
468 * receives them. This ensures that a stream can not hang up during
469 * initilization of a channel.
471 channel
->nb_init_stream_left
= 0;
473 /* The reply msg status is handled in the following call. */
474 ret
= create_ust_channel(attr
, &channel
->uchan
);
479 /* Open all streams for this channel. */
480 ret
= create_ust_streams(channel
, ctx
);
490 * Send all stream of a channel to the right thread handling it.
492 * On error, return a negative value else 0 on success.
494 static int send_streams_to_thread(struct lttng_consumer_channel
*channel
,
495 struct lttng_consumer_local_data
*ctx
)
498 struct lttng_consumer_stream
*stream
, *stmp
;
503 /* Send streams to the corresponding thread. */
504 cds_list_for_each_entry_safe(stream
, stmp
, &channel
->streams
.head
,
506 /* Sending the stream to the thread. */
507 ret
= send_stream_to_thread(stream
, ctx
);
510 * If we are unable to send the stream to the thread, there is
511 * a big problem so just stop everything.
516 /* Remove node from the channel stream list. */
517 cds_list_del(&stream
->send_node
);
525 * Write metadata to the given channel using ustctl to convert the string to
528 * Return 0 on success else a negative value.
530 static int push_metadata(struct lttng_consumer_channel
*metadata
,
531 const char *metadata_str
, uint64_t target_offset
, uint64_t len
)
536 assert(metadata_str
);
538 DBG("UST consumer writing metadata to channel %s", metadata
->name
);
540 assert(target_offset
== metadata
->contig_metadata_written
);
541 ret
= ustctl_write_metadata_to_channel(metadata
->uchan
, metadata_str
, len
);
543 ERR("ustctl write metadata fail with ret %d, len %ld", ret
, len
);
546 metadata
->contig_metadata_written
+= len
;
548 ustctl_flush_buffer(metadata
->metadata_stream
->ustream
, 1);
555 * Close metadata stream wakeup_fd using the given key to retrieve the channel.
557 * Return 0 on success else an LTTng error code.
559 static int close_metadata(uint64_t chan_key
)
562 struct lttng_consumer_channel
*channel
;
564 DBG("UST consumer close metadata key %lu", chan_key
);
566 channel
= consumer_find_channel(chan_key
);
568 ERR("UST consumer close metadata %lu not found", chan_key
);
569 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
573 ret
= ustctl_stream_close_wakeup_fd(channel
->metadata_stream
->ustream
);
575 ERR("UST consumer unable to close fd of metadata (ret: %d)", ret
);
576 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
585 * RCU read side lock MUST be acquired before calling this function.
587 * Return 0 on success else an LTTng error code.
589 static int setup_metadata(struct lttng_consumer_local_data
*ctx
, uint64_t key
)
592 struct lttng_consumer_channel
*metadata
;
594 DBG("UST consumer setup metadata key %lu", key
);
596 metadata
= consumer_find_channel(key
);
598 ERR("UST consumer push metadata %" PRIu64
" not found", key
);
599 ret
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
604 * Send metadata stream to relayd if one available. Availability is
605 * known if the stream is still in the list of the channel.
607 if (cds_list_empty(&metadata
->streams
.head
)) {
608 ERR("Metadata channel key %" PRIu64
", no stream available.", key
);
609 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
613 /* Send metadata stream to relayd if needed. */
614 ret
= send_stream_to_relayd(metadata
->metadata_stream
);
616 ret
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
620 ret
= send_streams_to_thread(metadata
, ctx
);
623 * If we are unable to send the stream to the thread, there is
624 * a big problem so just stop everything.
626 ret
= LTTCOMM_CONSUMERD_FATAL
;
629 /* List MUST be empty after or else it could be reused. */
630 assert(cds_list_empty(&metadata
->streams
.head
));
639 * Receive command from session daemon and process it.
641 * Return 1 on success else a negative value or 0.
643 int lttng_ustconsumer_recv_cmd(struct lttng_consumer_local_data
*ctx
,
644 int sock
, struct pollfd
*consumer_sockpoll
)
647 enum lttng_error_code ret_code
= LTTNG_OK
;
648 struct lttcomm_consumer_msg msg
;
649 struct lttng_consumer_channel
*channel
= NULL
;
651 ret
= lttcomm_recv_unix_sock(sock
, &msg
, sizeof(msg
));
652 if (ret
!= sizeof(msg
)) {
653 DBG("Consumer received unexpected message size %zd (expects %zu)",
655 lttng_consumer_send_error(ctx
, LTTCOMM_CONSUMERD_ERROR_RECV_CMD
);
657 * The ret value might 0 meaning an orderly shutdown but this is ok
658 * since the caller handles this.
662 if (msg
.cmd_type
== LTTNG_CONSUMER_STOP
) {
664 * Notify the session daemon that the command is completed.
666 * On transport layer error, the function call will print an error
667 * message so handling the returned code is a bit useless since we
668 * return an error code anyway.
670 (void) consumer_send_status_msg(sock
, ret_code
);
674 /* relayd needs RCU read-side lock */
677 switch (msg
.cmd_type
) {
678 case LTTNG_CONSUMER_ADD_RELAYD_SOCKET
:
680 /* Session daemon status message are handled in the following call. */
681 ret
= consumer_add_relayd_socket(msg
.u
.relayd_sock
.net_index
,
682 msg
.u
.relayd_sock
.type
, ctx
, sock
, consumer_sockpoll
,
683 &msg
.u
.relayd_sock
.sock
, msg
.u
.relayd_sock
.session_id
);
686 case LTTNG_CONSUMER_DESTROY_RELAYD
:
688 uint64_t index
= msg
.u
.destroy_relayd
.net_seq_idx
;
689 struct consumer_relayd_sock_pair
*relayd
;
691 DBG("UST consumer destroying relayd %" PRIu64
, index
);
693 /* Get relayd reference if exists. */
694 relayd
= consumer_find_relayd(index
);
695 if (relayd
== NULL
) {
696 DBG("Unable to find relayd %" PRIu64
, index
);
697 ret_code
= LTTNG_ERR_NO_CONSUMER
;
701 * Each relayd socket pair has a refcount of stream attached to it
702 * which tells if the relayd is still active or not depending on the
705 * This will set the destroy flag of the relayd object and destroy it
706 * if the refcount reaches zero when called.
708 * The destroy can happen either here or when a stream fd hangs up.
711 consumer_flag_relayd_for_destroy(relayd
);
714 goto end_msg_sessiond
;
716 case LTTNG_CONSUMER_UPDATE_STREAM
:
721 case LTTNG_CONSUMER_DATA_PENDING
:
723 int ret
, is_data_pending
;
724 uint64_t id
= msg
.u
.data_pending
.session_id
;
726 DBG("UST consumer data pending command for id %" PRIu64
, id
);
728 is_data_pending
= consumer_data_pending(id
);
730 /* Send back returned value to session daemon */
731 ret
= lttcomm_send_unix_sock(sock
, &is_data_pending
,
732 sizeof(is_data_pending
));
734 DBG("Error when sending the data pending ret code: %d", ret
);
738 * No need to send back a status message since the data pending
739 * returned value is the response.
743 case LTTNG_CONSUMER_ASK_CHANNEL_CREATION
:
746 struct ustctl_consumer_channel_attr attr
;
748 /* Create a plain object and reserve a channel key. */
749 channel
= allocate_channel(msg
.u
.ask_channel
.session_id
,
750 msg
.u
.ask_channel
.pathname
, msg
.u
.ask_channel
.name
,
751 msg
.u
.ask_channel
.uid
, msg
.u
.ask_channel
.gid
,
752 msg
.u
.ask_channel
.relayd_id
, msg
.u
.ask_channel
.key
,
753 (enum lttng_event_output
) msg
.u
.ask_channel
.output
);
755 goto end_channel_error
;
758 /* Build channel attributes from received message. */
759 attr
.subbuf_size
= msg
.u
.ask_channel
.subbuf_size
;
760 attr
.num_subbuf
= msg
.u
.ask_channel
.num_subbuf
;
761 attr
.overwrite
= msg
.u
.ask_channel
.overwrite
;
762 attr
.switch_timer_interval
= msg
.u
.ask_channel
.switch_timer_interval
;
763 attr
.read_timer_interval
= msg
.u
.ask_channel
.read_timer_interval
;
764 memcpy(attr
.uuid
, msg
.u
.ask_channel
.uuid
, sizeof(attr
.uuid
));
766 /* Translate the event output type to UST. */
767 switch (channel
->output
) {
768 case LTTNG_EVENT_SPLICE
:
769 /* Splice not supported so fallback on mmap(). */
770 case LTTNG_EVENT_MMAP
:
772 attr
.output
= CONSUMER_CHANNEL_MMAP
;
776 /* Translate and save channel type. */
777 switch (msg
.u
.ask_channel
.type
) {
778 case LTTNG_UST_CHAN_PER_CPU
:
779 channel
->type
= CONSUMER_CHANNEL_TYPE_DATA
;
780 attr
.type
= LTTNG_UST_CHAN_PER_CPU
;
782 case LTTNG_UST_CHAN_METADATA
:
783 channel
->type
= CONSUMER_CHANNEL_TYPE_METADATA
;
784 attr
.type
= LTTNG_UST_CHAN_METADATA
;
791 ret
= ask_channel(ctx
, sock
, channel
, &attr
);
793 goto end_channel_error
;
797 * Add the channel to the internal state AFTER all streams were created
798 * and successfully sent to session daemon. This way, all streams must
799 * be ready before this channel is visible to the threads.
801 ret
= add_channel(channel
, ctx
);
803 goto end_channel_error
;
807 * Channel and streams are now created. Inform the session daemon that
808 * everything went well and should wait to receive the channel and
809 * streams with ustctl API.
811 ret
= consumer_send_status_channel(sock
, channel
);
814 * There is probably a problem on the socket so the poll will get
815 * it and clean everything up.
822 case LTTNG_CONSUMER_GET_CHANNEL
:
824 int ret
, relayd_err
= 0;
825 uint64_t key
= msg
.u
.get_channel
.key
;
826 struct lttng_consumer_channel
*channel
;
828 channel
= consumer_find_channel(key
);
830 ERR("UST consumer get channel key %lu not found", key
);
831 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
832 goto end_msg_sessiond
;
835 /* Inform sessiond that we are about to send channel and streams. */
836 ret
= consumer_send_status_msg(sock
, LTTNG_OK
);
838 /* Somehow, the session daemon is not responding anymore. */
842 /* Send everything to sessiond. */
843 ret
= send_sessiond_channel(sock
, channel
, ctx
, &relayd_err
);
847 * We were unable to send to the relayd the stream so avoid
848 * sending back a fatal error to the thread since this is OK
849 * and the consumer can continue its work.
851 ret_code
= LTTNG_ERR_RELAYD_CONNECT_FAIL
;
852 goto end_msg_sessiond
;
855 * The communicaton was broken hence there is a bad state between
856 * the consumer and sessiond so stop everything.
861 ret
= send_streams_to_thread(channel
, ctx
);
864 * If we are unable to send the stream to the thread, there is
865 * a big problem so just stop everything.
869 /* List MUST be empty after or else it could be reused. */
870 assert(cds_list_empty(&channel
->streams
.head
));
872 goto end_msg_sessiond
;
874 case LTTNG_CONSUMER_DESTROY_CHANNEL
:
876 uint64_t key
= msg
.u
.destroy_channel
.key
;
877 struct lttng_consumer_channel
*channel
;
879 channel
= consumer_find_channel(key
);
881 ERR("UST consumer get channel key %lu not found", key
);
882 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
883 goto end_msg_sessiond
;
886 destroy_channel(channel
);
888 goto end_msg_sessiond
;
890 case LTTNG_CONSUMER_CLOSE_METADATA
:
894 ret
= close_metadata(msg
.u
.close_metadata
.key
);
899 goto end_msg_sessiond
;
901 case LTTNG_CONSUMER_PUSH_METADATA
:
904 uint64_t len
= msg
.u
.push_metadata
.len
;
905 uint64_t target_offset
= msg
.u
.push_metadata
.target_offset
;
906 uint64_t key
= msg
.u
.push_metadata
.key
;
907 struct lttng_consumer_channel
*channel
;
910 DBG("UST consumer push metadata key %lu of len %lu", key
, len
);
912 channel
= consumer_find_channel(key
);
914 ERR("UST consumer push metadata %lu not found", key
);
915 ret_code
= LTTNG_ERR_UST_CHAN_NOT_FOUND
;
918 metadata_str
= zmalloc(len
* sizeof(char));
920 PERROR("zmalloc metadata string");
921 ret_code
= LTTCOMM_CONSUMERD_ENOMEM
;
922 goto end_msg_sessiond
;
925 /* Tell session daemon we are ready to receive the metadata. */
926 ret
= consumer_send_status_msg(sock
, LTTNG_OK
);
928 /* Somehow, the session daemon is not responding anymore. */
932 /* Wait for more data. */
933 if (lttng_consumer_poll_socket(consumer_sockpoll
) < 0) {
937 /* Receive metadata string. */
938 ret
= lttcomm_recv_unix_sock(sock
, metadata_str
, len
);
940 /* Session daemon is dead so return gracefully. */
944 ret
= push_metadata(channel
, metadata_str
, target_offset
, len
);
947 /* Unable to handle metadata. Notify session daemon. */
948 ret_code
= LTTCOMM_CONSUMERD_ERROR_METADATA
;
949 goto end_msg_sessiond
;
952 goto end_msg_sessiond
;
954 case LTTNG_CONSUMER_SETUP_METADATA
:
958 ret
= setup_metadata(ctx
, msg
.u
.setup_metadata
.key
);
962 goto end_msg_sessiond
;
972 * Return 1 to indicate success since the 0 value can be a socket
973 * shutdown during the recv() or send() call.
979 * The returned value here is not useful since either way we'll return 1 to
980 * the caller because the session daemon socket management is done
981 * elsewhere. Returning a negative code or 0 will shutdown the consumer.
983 (void) consumer_send_status_msg(sock
, ret_code
);
989 * Free channel here since no one has a reference to it. We don't
990 * free after that because a stream can store this pointer.
992 destroy_channel(channel
);
994 /* We have to send a status channel message indicating an error. */
995 ret
= consumer_send_status_channel(sock
, NULL
);
997 /* Stop everything if session daemon can not be notified. */
1004 /* This will issue a consumer stop. */
1009 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1010 * compiled out, we isolate it in this library.
1012 int lttng_ustctl_get_mmap_read_offset(struct lttng_consumer_stream
*stream
,
1016 assert(stream
->ustream
);
1018 return ustctl_get_mmap_read_offset(stream
->ustream
, off
);
1022 * Wrapper over the mmap() read offset from ust-ctl library. Since this can be
1023 * compiled out, we isolate it in this library.
1025 void *lttng_ustctl_get_mmap_base(struct lttng_consumer_stream
*stream
)
1028 assert(stream
->ustream
);
1030 return ustctl_get_mmap_base(stream
->ustream
);
1034 * Take a snapshot for a specific fd
1036 * Returns 0 on success, < 0 on error
1038 int lttng_ustconsumer_take_snapshot(struct lttng_consumer_stream
*stream
)
1041 assert(stream
->ustream
);
1043 return ustctl_snapshot(stream
->ustream
);
1047 * Get the produced position
1049 * Returns 0 on success, < 0 on error
1051 int lttng_ustconsumer_get_produced_snapshot(
1052 struct lttng_consumer_stream
*stream
, unsigned long *pos
)
1055 assert(stream
->ustream
);
1058 return ustctl_snapshot_get_produced(stream
->ustream
, pos
);
1062 * Called when the stream signal the consumer that it has hang up.
1064 void lttng_ustconsumer_on_stream_hangup(struct lttng_consumer_stream
*stream
)
1067 assert(stream
->ustream
);
1069 ustctl_flush_buffer(stream
->ustream
, 0);
1070 stream
->hangup_flush_done
= 1;
1073 void lttng_ustconsumer_del_channel(struct lttng_consumer_channel
*chan
)
1076 assert(chan
->uchan
);
1078 ustctl_destroy_channel(chan
->uchan
);
1081 void lttng_ustconsumer_del_stream(struct lttng_consumer_stream
*stream
)
1084 assert(stream
->ustream
);
1086 ustctl_destroy_stream(stream
->ustream
);
1089 int lttng_ustconsumer_read_subbuffer(struct lttng_consumer_stream
*stream
,
1090 struct lttng_consumer_local_data
*ctx
)
1092 unsigned long len
, subbuf_size
, padding
;
1096 struct ustctl_consumer_stream
*ustream
;
1099 assert(stream
->ustream
);
1102 DBG2("In UST read_subbuffer (wait_fd: %d, name: %s)", stream
->wait_fd
,
1105 /* Ease our life for what's next. */
1106 ustream
= stream
->ustream
;
1108 /* We can consume the 1 byte written into the wait_fd by UST */
1109 if (!stream
->hangup_flush_done
) {
1113 readlen
= read(stream
->wait_fd
, &dummy
, 1);
1114 } while (readlen
== -1 && errno
== EINTR
);
1115 if (readlen
== -1) {
1121 /* Get the next subbuffer */
1122 err
= ustctl_get_next_subbuf(ustream
);
1124 ret
= err
; /* ustctl_get_next_subbuf returns negative, caller expect positive. */
1126 * This is a debug message even for single-threaded consumer,
1127 * because poll() have more relaxed criterions than get subbuf,
1128 * so get_subbuf may fail for short race windows where poll()
1129 * would issue wakeups.
1131 DBG("Reserving sub buffer failed (everything is normal, "
1132 "it is due to concurrency) [ret: %d]", err
);
1135 assert(stream
->chan
->output
== CONSUMER_CHANNEL_MMAP
);
1136 /* Get the full padded subbuffer size */
1137 err
= ustctl_get_padded_subbuf_size(ustream
, &len
);
1140 /* Get subbuffer data size (without padding) */
1141 err
= ustctl_get_subbuf_size(ustream
, &subbuf_size
);
1144 /* Make sure we don't get a subbuffer size bigger than the padded */
1145 assert(len
>= subbuf_size
);
1147 padding
= len
- subbuf_size
;
1148 /* write the subbuffer to the tracefile */
1149 ret
= lttng_consumer_on_read_subbuffer_mmap(ctx
, stream
, subbuf_size
, padding
);
1151 * The mmap operation should write subbuf_size amount of data when network
1152 * streaming or the full padding (len) size when we are _not_ streaming.
1154 if ((ret
!= subbuf_size
&& stream
->net_seq_idx
!= (uint64_t) -1ULL) ||
1155 (ret
!= len
&& stream
->net_seq_idx
== (uint64_t) -1ULL)) {
1157 * Display the error but continue processing to try to release the
1158 * subbuffer. This is a DBG statement since any unexpected kill or
1159 * signal, the application gets unregistered, relayd gets closed or
1160 * anything that affects the buffer lifetime will trigger this error.
1161 * So, for the sake of the user, don't print this error since it can
1162 * happen and it is OK with the code flow.
1164 DBG("Error writing to tracefile "
1165 "(ret: %zd != len: %lu != subbuf_size: %lu)",
1166 ret
, len
, subbuf_size
);
1168 err
= ustctl_put_next_subbuf(ustream
);
1175 * Called when a stream is created.
1177 int lttng_ustconsumer_on_recv_stream(struct lttng_consumer_stream
*stream
)
1180 char full_path
[PATH_MAX
];
1182 /* Opening the tracefile in write mode */
1183 if (stream
->net_seq_idx
!= (uint64_t) -1ULL) {
1187 ret
= snprintf(full_path
, sizeof(full_path
), "%s/%s",
1188 stream
->chan
->pathname
, stream
->name
);
1190 PERROR("snprintf on_recv_stream");
1194 ret
= run_as_open(full_path
, O_WRONLY
| O_CREAT
| O_TRUNC
,
1195 S_IRWXU
| S_IRWXG
| S_IRWXO
, stream
->uid
, stream
->gid
);
1197 PERROR("open stream path %s", full_path
);
1200 stream
->out_fd
= ret
;
1203 /* we return 0 to let the library handle the FD internally */
1211 * Check if data is still being extracted from the buffers for a specific
1212 * stream. Consumer data lock MUST be acquired before calling this function
1213 * and the stream lock.
1215 * Return 1 if the traced data are still getting read else 0 meaning that the
1216 * data is available for trace viewer reading.
1218 int lttng_ustconsumer_data_pending(struct lttng_consumer_stream
*stream
)
1223 assert(stream
->ustream
);
1225 DBG("UST consumer checking data pending");
1227 ret
= ustctl_get_next_subbuf(stream
->ustream
);
1229 /* There is still data so let's put back this subbuffer. */
1230 ret
= ustctl_put_subbuf(stream
->ustream
);
1232 ret
= 1; /* Data is pending */
1236 /* Data is NOT pending so ready to be read. */
1244 * Close every metadata stream wait fd of the metadata hash table. This
1245 * function MUST be used very carefully so not to run into a race between the
1246 * metadata thread handling streams and this function closing their wait fd.
1248 * For UST, this is used when the session daemon hangs up. Its the metadata
1249 * producer so calling this is safe because we are assured that no state change
1250 * can occur in the metadata thread for the streams in the hash table.
1252 void lttng_ustconsumer_close_metadata(struct lttng_ht
*metadata_ht
)
1255 struct lttng_ht_iter iter
;
1256 struct lttng_consumer_stream
*stream
;
1258 assert(metadata_ht
);
1259 assert(metadata_ht
->ht
);
1261 DBG("UST consumer closing all metadata streams");
1264 cds_lfht_for_each_entry(metadata_ht
->ht
, &iter
.iter
, stream
,
1266 int fd
= stream
->wait_fd
;
1269 * Whatever happens here we have to continue to try to close every
1270 * streams. Let's report at least the error on failure.
1272 ret
= ustctl_stream_close_wakeup_fd(stream
->ustream
);
1274 ERR("Unable to close metadata stream fd %d ret %d", fd
, ret
);
1276 DBG("Metadata wait fd %d closed", fd
);