2 * Copyright (C) 2013 Julien Desfossez <jdesfossez@efficios.com>
3 * Copyright (C) 2013 David Goulet <dgoulet@efficios.com>
4 * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
6 * SPDX-License-Identifier: GPL-2.0-only
12 #include "connection.hpp"
13 #include "ctf-trace.hpp"
14 #include "health-relayd.hpp"
16 #include "lttng-relayd.hpp"
17 #include "session.hpp"
19 #include "testpoint.hpp"
21 #include "viewer-session.hpp"
22 #include "viewer-stream.hpp"
24 #include <common/common.hpp>
25 #include <common/compat/endian.hpp>
26 #include <common/compat/poll.hpp>
27 #include <common/compat/socket.hpp>
28 #include <common/defaults.hpp>
29 #include <common/fd-tracker/utils.hpp>
30 #include <common/fs-handle.hpp>
31 #include <common/futex.hpp>
32 #include <common/index/index.hpp>
33 #include <common/sessiond-comm/inet.hpp>
34 #include <common/sessiond-comm/relayd.hpp>
35 #include <common/sessiond-comm/sessiond-comm.hpp>
36 #include <common/uri.hpp>
37 #include <common/utils.hpp>
39 #include <lttng/lttng.h>
53 #include <sys/mount.h>
54 #include <sys/resource.h>
55 #include <sys/socket.h>
57 #include <sys/types.h>
60 #include <urcu/futex.h>
61 #include <urcu/rculist.h>
62 #include <urcu/uatomic.h>
64 #define SESSION_BUF_DEFAULT_COUNT 16
66 static struct lttng_uri
*live_uri
;
69 * This pipe is used to inform the worker thread that a command is queued and
70 * ready to be processed.
72 static int live_conn_pipe
[2] = { -1, -1 };
74 /* Shared between threads */
75 static int live_dispatch_thread_exit
;
77 static pthread_t live_listener_thread
;
78 static pthread_t live_dispatcher_thread
;
79 static pthread_t live_worker_thread
;
82 * Relay command queue.
84 * The live_thread_listener and live_thread_dispatcher communicate with this
87 static struct relay_conn_queue viewer_conn_queue
;
89 static uint64_t last_relay_viewer_session_id
;
90 static pthread_mutex_t last_relay_viewer_session_id_lock
= PTHREAD_MUTEX_INITIALIZER
;
92 static const char *lttng_viewer_command_str(lttng_viewer_command cmd
)
95 case LTTNG_VIEWER_CONNECT
:
97 case LTTNG_VIEWER_LIST_SESSIONS
:
98 return "LIST_SESSIONS";
99 case LTTNG_VIEWER_ATTACH_SESSION
:
100 return "ATTACH_SESSION";
101 case LTTNG_VIEWER_GET_NEXT_INDEX
:
102 return "GET_NEXT_INDEX";
103 case LTTNG_VIEWER_GET_PACKET
:
105 case LTTNG_VIEWER_GET_METADATA
:
106 return "GET_METADATA";
107 case LTTNG_VIEWER_GET_NEW_STREAMS
:
108 return "GET_NEW_STREAMS";
109 case LTTNG_VIEWER_CREATE_SESSION
:
110 return "CREATE_SESSION";
111 case LTTNG_VIEWER_DETACH_SESSION
:
112 return "DETACH_SESSION";
119 lttng_viewer_next_index_return_code_str(enum lttng_viewer_next_index_return_code code
)
122 case LTTNG_VIEWER_INDEX_OK
:
124 case LTTNG_VIEWER_INDEX_RETRY
:
125 return "INDEX_RETRY";
126 case LTTNG_VIEWER_INDEX_HUP
:
128 case LTTNG_VIEWER_INDEX_ERR
:
130 case LTTNG_VIEWER_INDEX_INACTIVE
:
131 return "INDEX_INACTIVE";
132 case LTTNG_VIEWER_INDEX_EOF
:
139 static const char *lttng_viewer_attach_return_code_str(enum lttng_viewer_attach_return_code code
)
142 case LTTNG_VIEWER_ATTACH_OK
:
144 case LTTNG_VIEWER_ATTACH_ALREADY
:
145 return "ATTACH_ALREADY";
146 case LTTNG_VIEWER_ATTACH_UNK
:
148 case LTTNG_VIEWER_ATTACH_NOT_LIVE
:
149 return "ATTACH_NOT_LIVE";
150 case LTTNG_VIEWER_ATTACH_SEEK_ERR
:
151 return "ATTACH_SEEK_ERR";
152 case LTTNG_VIEWER_ATTACH_NO_SESSION
:
153 return "ATTACH_NO_SESSION";
160 lttng_viewer_get_packet_return_code_str(enum lttng_viewer_get_packet_return_code code
)
163 case LTTNG_VIEWER_GET_PACKET_OK
:
164 return "GET_PACKET_OK";
165 case LTTNG_VIEWER_GET_PACKET_RETRY
:
166 return "GET_PACKET_RETRY";
167 case LTTNG_VIEWER_GET_PACKET_ERR
:
168 return "GET_PACKET_ERR";
169 case LTTNG_VIEWER_GET_PACKET_EOF
:
170 return "GET_PACKET_EOF";
179 static void cleanup_relayd_live()
187 * Receive a request buffer using a given socket, destination allocated buffer
190 * Return the size of the received message or else a negative value on error
191 * with errno being set by recvmsg() syscall.
193 static ssize_t
recv_request(struct lttcomm_sock
*sock
, void *buf
, size_t size
)
197 ret
= sock
->ops
->recvmsg(sock
, buf
, size
, 0);
198 if (ret
< 0 || ret
!= size
) {
200 /* Orderly shutdown. Not necessary to print an error. */
201 DBG("Socket %d did an orderly shutdown", sock
->fd
);
203 ERR("Relay failed to receive request.");
212 * Send a response buffer using a given socket, source allocated buffer of
215 * Return the size of the sent message or else a negative value on error with
216 * errno being set by sendmsg() syscall.
218 static ssize_t
send_response(struct lttcomm_sock
*sock
, void *buf
, size_t size
)
222 ret
= sock
->ops
->sendmsg(sock
, buf
, size
, 0);
224 ERR("Relayd failed to send response.");
231 * Atomically check if new streams got added in one of the sessions attached
232 * and reset the flag to 0.
234 * Returns 1 if new streams got added, 0 if nothing changed, a negative value
237 static int check_new_streams(struct relay_connection
*conn
)
239 struct relay_session
*session
;
240 unsigned long current_val
;
243 if (!conn
->viewer_session
) {
247 cds_list_for_each_entry_rcu(
248 session
, &conn
->viewer_session
->session_list
, viewer_session_node
)
250 if (!session_get(session
)) {
253 current_val
= uatomic_cmpxchg(&session
->new_streams
, 1, 0);
255 session_put(session
);
266 * Send viewer streams to the given socket. The ignore_sent_flag indicates if
267 * this function should ignore the sent flag or not.
269 * Return 0 on success or else a negative value.
272 send_viewer_streams(struct lttcomm_sock
*sock
, uint64_t session_id
, unsigned int ignore_sent_flag
)
275 struct lttng_ht_iter iter
;
276 struct relay_viewer_stream
*vstream
;
280 cds_lfht_for_each_entry (viewer_streams_ht
->ht
, &iter
.iter
, vstream
, stream_n
.node
) {
281 struct ctf_trace
*ctf_trace
;
282 struct lttng_viewer_stream send_stream
= {};
284 health_code_update();
286 if (!viewer_stream_get(vstream
)) {
290 pthread_mutex_lock(&vstream
->stream
->lock
);
291 /* Ignore if not the same session. */
292 if (vstream
->stream
->trace
->session
->id
!= session_id
||
293 (!ignore_sent_flag
&& vstream
->sent_flag
)) {
294 pthread_mutex_unlock(&vstream
->stream
->lock
);
295 viewer_stream_put(vstream
);
299 ctf_trace
= vstream
->stream
->trace
;
300 send_stream
.id
= htobe64(vstream
->stream
->stream_handle
);
301 send_stream
.ctf_trace_id
= htobe64(ctf_trace
->id
);
302 send_stream
.metadata_flag
= htobe32(vstream
->stream
->is_metadata
);
303 if (lttng_strncpy(send_stream
.path_name
,
305 sizeof(send_stream
.path_name
))) {
306 pthread_mutex_unlock(&vstream
->stream
->lock
);
307 viewer_stream_put(vstream
);
308 ret
= -1; /* Error. */
311 if (lttng_strncpy(send_stream
.channel_name
,
312 vstream
->channel_name
,
313 sizeof(send_stream
.channel_name
))) {
314 pthread_mutex_unlock(&vstream
->stream
->lock
);
315 viewer_stream_put(vstream
);
316 ret
= -1; /* Error. */
320 DBG("Sending stream %" PRIu64
" to viewer", vstream
->stream
->stream_handle
);
321 vstream
->sent_flag
= true;
322 pthread_mutex_unlock(&vstream
->stream
->lock
);
324 ret
= send_response(sock
, &send_stream
, sizeof(send_stream
));
325 viewer_stream_put(vstream
);
339 * Create every viewer stream possible for the given session with the seek
340 * type. Three counters *can* be return which are in order the total amount of
341 * viewer stream of the session, the number of unsent stream and the number of
342 * stream created. Those counters can be NULL and thus will be ignored.
344 * session must be locked to ensure that we see either none or all initial
345 * streams for a session, but no intermediate state..
347 * Return 0 on success or else a negative value.
349 static int make_viewer_streams(struct relay_session
*relay_session
,
350 struct relay_viewer_session
*viewer_session
,
351 enum lttng_viewer_seek seek_t
,
354 uint32_t *nb_created
,
358 struct lttng_ht_iter iter
;
359 struct ctf_trace
*ctf_trace
;
360 struct relay_stream
*relay_stream
= nullptr;
362 LTTNG_ASSERT(relay_session
);
363 ASSERT_LOCKED(relay_session
->lock
);
365 if (relay_session
->connection_closed
) {
370 * Create viewer streams for relay streams that are ready to be
371 * used for a the given session id only.
374 cds_lfht_for_each_entry (
375 relay_session
->ctf_traces_ht
->ht
, &iter
.iter
, ctf_trace
, node
.node
) {
376 bool trace_has_metadata_stream
= false;
378 health_code_update();
380 if (!ctf_trace_get(ctf_trace
)) {
385 * Iterate over all the streams of the trace to see if we have a
388 cds_list_for_each_entry_rcu(relay_stream
, &ctf_trace
->stream_list
, stream_node
)
390 bool is_metadata_stream
;
392 pthread_mutex_lock(&relay_stream
->lock
);
393 is_metadata_stream
= relay_stream
->is_metadata
;
394 pthread_mutex_unlock(&relay_stream
->lock
);
396 if (is_metadata_stream
) {
397 trace_has_metadata_stream
= true;
402 relay_stream
= nullptr;
405 * If there is no metadata stream in this trace at the moment
406 * and we never sent one to the viewer, skip the trace. We
407 * accept that the viewer will not see this trace at all.
409 if (!trace_has_metadata_stream
&& !ctf_trace
->metadata_stream_sent_to_viewer
) {
410 ctf_trace_put(ctf_trace
);
414 cds_list_for_each_entry_rcu(relay_stream
, &ctf_trace
->stream_list
, stream_node
)
416 struct relay_viewer_stream
*viewer_stream
;
418 if (!stream_get(relay_stream
)) {
422 pthread_mutex_lock(&relay_stream
->lock
);
424 * stream published is protected by the session lock.
426 if (!relay_stream
->published
) {
429 viewer_stream
= viewer_stream_get_by_id(relay_stream
->stream_handle
);
430 if (!viewer_stream
) {
431 struct lttng_trace_chunk
*viewer_stream_trace_chunk
= nullptr;
434 * Save that we sent the metadata stream to the
435 * viewer. So that we know what trace the viewer
438 if (relay_stream
->is_metadata
) {
439 ctf_trace
->metadata_stream_sent_to_viewer
= true;
443 * If a rotation is ongoing, use a copy of the
444 * relay stream's chunk to ensure the stream
447 * Otherwise, the viewer session's current trace
448 * chunk can be used safely.
450 if ((relay_stream
->ongoing_rotation
.is_set
||
451 session_has_ongoing_rotation(relay_session
)) &&
452 relay_stream
->trace_chunk
) {
453 viewer_stream_trace_chunk
=
454 lttng_trace_chunk_copy(relay_stream
->trace_chunk
);
455 if (!viewer_stream_trace_chunk
) {
457 ctf_trace_put(ctf_trace
);
462 * Transition the viewer session into the newest trace chunk
465 if (!lttng_trace_chunk_ids_equal(
466 viewer_session
->current_trace_chunk
,
467 relay_stream
->trace_chunk
)) {
468 ret
= viewer_session_set_trace_chunk_copy(
469 viewer_session
, relay_stream
->trace_chunk
);
472 ctf_trace_put(ctf_trace
);
477 if (relay_stream
->trace_chunk
) {
479 * If the corresponding relay
480 * stream's trace chunk is set,
481 * the viewer stream will be
484 * Note that a relay stream can
485 * have a NULL output trace
486 * chunk (for instance, after a
487 * clear against a stopped
490 const bool reference_acquired
=
491 lttng_trace_chunk_get(
492 viewer_session
->current_trace_chunk
);
494 LTTNG_ASSERT(reference_acquired
);
495 viewer_stream_trace_chunk
=
496 viewer_session
->current_trace_chunk
;
500 viewer_stream
= viewer_stream_create(
501 relay_stream
, viewer_stream_trace_chunk
, seek_t
);
502 lttng_trace_chunk_put(viewer_stream_trace_chunk
);
503 viewer_stream_trace_chunk
= nullptr;
504 if (!viewer_stream
) {
506 ctf_trace_put(ctf_trace
);
511 /* Update number of created stream counter. */
515 * Ensure a self-reference is preserved even
516 * after we have put our local reference.
518 if (!viewer_stream_get(viewer_stream
)) {
519 ERR("Unable to get self-reference on viewer stream, logic error.");
523 if (!viewer_stream
->sent_flag
&& nb_unsent
) {
524 /* Update number of unsent stream counter. */
528 /* Update number of total stream counter. */
530 if (relay_stream
->is_metadata
) {
531 if (!relay_stream
->closed
||
532 relay_stream
->metadata_received
>
533 viewer_stream
->metadata_sent
) {
537 if (!relay_stream
->closed
||
538 !(((int64_t) (relay_stream
->prev_data_seq
-
539 relay_stream
->last_net_seq_num
)) >= 0)) {
544 /* Put local reference. */
545 viewer_stream_put(viewer_stream
);
547 pthread_mutex_unlock(&relay_stream
->lock
);
548 stream_put(relay_stream
);
550 relay_stream
= nullptr;
551 ctf_trace_put(ctf_trace
);
560 pthread_mutex_unlock(&relay_stream
->lock
);
561 stream_put(relay_stream
);
567 int relayd_live_stop()
569 /* Stop dispatch thread */
570 CMM_STORE_SHARED(live_dispatch_thread_exit
, 1);
571 futex_nto1_wake(&viewer_conn_queue
.futex
);
575 static int create_sock(void *data
, int *out_fd
)
578 struct lttcomm_sock
*sock
= (lttcomm_sock
*) data
;
580 ret
= lttcomm_create_sock(sock
);
590 static int close_sock(void *data
, int *in_fd
__attribute__((unused
)))
592 struct lttcomm_sock
*sock
= (lttcomm_sock
*) data
;
594 return sock
->ops
->close(sock
);
597 static int accept_sock(void *data
, int *out_fd
)
600 /* Socks is an array of in_sock, out_sock. */
601 struct lttcomm_sock
**socks
= (lttcomm_sock
**) data
;
602 struct lttcomm_sock
*in_sock
= socks
[0];
604 socks
[1] = in_sock
->ops
->accept(in_sock
);
609 *out_fd
= socks
[1]->fd
;
614 static struct lttcomm_sock
*accept_live_sock(struct lttcomm_sock
*listening_sock
, const char *name
)
617 struct lttcomm_sock
*socks
[2] = { listening_sock
, nullptr };
618 struct lttcomm_sock
*new_sock
= nullptr;
620 ret
= fd_tracker_open_unsuspendable_fd(
621 the_fd_tracker
, &out_fd
, (const char **) &name
, 1, accept_sock
, &socks
);
626 DBG("%s accepted, socket %d", name
, new_sock
->fd
);
632 * Create and init socket from uri.
634 static struct lttcomm_sock
*init_socket(struct lttng_uri
*uri
, const char *name
)
637 struct lttcomm_sock
*sock
= nullptr;
638 char uri_str
[LTTNG_PATH_MAX
];
639 char *formated_name
= nullptr;
641 sock
= lttcomm_alloc_sock_from_uri(uri
);
642 if (sock
== nullptr) {
643 ERR("Allocating socket");
648 * Don't fail to create the socket if the name can't be built as it is
649 * only used for debugging purposes.
651 ret
= uri_to_str_url(uri
, uri_str
, sizeof(uri_str
));
652 uri_str
[sizeof(uri_str
) - 1] = '\0';
654 ret
= asprintf(&formated_name
, "%s socket @ %s", name
, uri_str
);
656 formated_name
= nullptr;
660 ret
= fd_tracker_open_unsuspendable_fd(the_fd_tracker
,
662 (const char **) (formated_name
? &formated_name
:
668 PERROR("Failed to create \"%s\" socket", formated_name
?: "Unknown");
671 DBG("Listening on %s socket %d", name
, sock
->fd
);
673 ret
= sock
->ops
->bind(sock
);
675 PERROR("Failed to bind lttng-live socket");
679 ret
= sock
->ops
->listen(sock
, -1);
689 lttcomm_destroy_sock(sock
);
696 * This thread manages the listening for new connections on the network
698 static void *thread_listener(void *data
__attribute__((unused
)))
700 int i
, ret
, err
= -1;
702 struct lttng_poll_event events
;
703 struct lttcomm_sock
*live_control_sock
;
705 DBG("[thread] Relay live listener started");
707 rcu_register_thread();
708 health_register(health_relayd
, HEALTH_RELAYD_TYPE_LIVE_LISTENER
);
710 health_code_update();
712 live_control_sock
= init_socket(live_uri
, "Live listener");
713 if (!live_control_sock
) {
714 goto error_sock_control
;
717 /* Pass 2 as size here for the thread quit pipe and control sockets. */
718 ret
= create_named_thread_poll_set(&events
, 2, "Live listener thread epoll");
720 goto error_create_poll
;
723 /* Add the control socket */
724 ret
= lttng_poll_add(&events
, live_control_sock
->fd
, LPOLLIN
| LPOLLRDHUP
);
729 lttng_relay_notify_ready();
731 if (testpoint(relayd_thread_live_listener
)) {
732 goto error_testpoint
;
736 health_code_update();
738 DBG("Listener accepting live viewers connections");
742 ret
= lttng_poll_wait(&events
, -1);
746 * Restart interrupted system call.
748 if (errno
== EINTR
) {
755 DBG("Relay new viewer connection received");
756 for (i
= 0; i
< nb_fd
; i
++) {
757 /* Fetch once the poll data */
758 const auto revents
= LTTNG_POLL_GETEV(&events
, i
);
759 const auto pollfd
= LTTNG_POLL_GETFD(&events
, i
);
761 health_code_update();
763 /* Activity on thread quit pipe, exiting. */
764 if (relayd_is_thread_quit_pipe(pollfd
)) {
765 DBG("Activity on thread quit pipe");
770 if (revents
& LPOLLIN
) {
772 * A new connection is requested, therefore a
773 * viewer connection is allocated in this
774 * thread, enqueued to a global queue and
775 * dequeued (and freed) in the worker thread.
778 struct relay_connection
*new_conn
;
779 struct lttcomm_sock
*newsock
;
781 newsock
= accept_live_sock(live_control_sock
,
782 "Live socket to client");
784 PERROR("accepting control sock");
787 DBG("Relay viewer connection accepted socket %d", newsock
->fd
);
790 newsock
->fd
, SOL_SOCKET
, SO_REUSEADDR
, &val
, sizeof(val
));
792 PERROR("setsockopt inet");
793 lttcomm_destroy_sock(newsock
);
796 new_conn
= connection_create(newsock
, RELAY_CONNECTION_UNKNOWN
);
798 lttcomm_destroy_sock(newsock
);
801 /* Ownership assumed by the connection. */
804 /* Enqueue request for the dispatcher thread. */
805 cds_wfcq_head_ptr_t head
;
806 head
.h
= &viewer_conn_queue
.head
;
807 cds_wfcq_enqueue(head
, &viewer_conn_queue
.tail
, &new_conn
->qnode
);
810 * Wake the dispatch queue futex.
811 * Implicit memory barrier with the
812 * exchange in cds_wfcq_enqueue.
814 futex_nto1_wake(&viewer_conn_queue
.futex
);
815 } else if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
816 ERR("socket poll error");
819 ERR("Unexpected poll events %u for sock %d", revents
, pollfd
);
829 (void) fd_tracker_util_poll_clean(the_fd_tracker
, &events
);
831 if (live_control_sock
->fd
>= 0) {
832 int sock_fd
= live_control_sock
->fd
;
834 ret
= fd_tracker_close_unsuspendable_fd(
835 the_fd_tracker
, &sock_fd
, 1, close_sock
, live_control_sock
);
839 live_control_sock
->fd
= -1;
841 lttcomm_destroy_sock(live_control_sock
);
845 DBG("Live viewer listener thread exited with error");
847 health_unregister(health_relayd
);
848 rcu_unregister_thread();
849 DBG("Live viewer listener thread cleanup complete");
850 if (lttng_relay_stop_threads()) {
851 ERR("Error stopping threads");
857 * This thread manages the dispatching of the requests to worker threads
859 static void *thread_dispatcher(void *data
__attribute__((unused
)))
863 struct cds_wfcq_node
*node
;
864 struct relay_connection
*conn
= nullptr;
866 DBG("[thread] Live viewer relay dispatcher started");
868 health_register(health_relayd
, HEALTH_RELAYD_TYPE_LIVE_DISPATCHER
);
870 if (testpoint(relayd_thread_live_dispatcher
)) {
871 goto error_testpoint
;
874 health_code_update();
877 health_code_update();
879 /* Atomically prepare the queue futex */
880 futex_nto1_prepare(&viewer_conn_queue
.futex
);
882 if (CMM_LOAD_SHARED(live_dispatch_thread_exit
)) {
887 health_code_update();
889 /* Dequeue commands */
890 node
= cds_wfcq_dequeue_blocking(&viewer_conn_queue
.head
,
891 &viewer_conn_queue
.tail
);
892 if (node
== nullptr) {
893 DBG("Woken up but nothing in the live-viewer "
894 "relay command queue");
895 /* Continue thread execution */
898 conn
= lttng::utils::container_of(node
, &relay_connection::qnode
);
899 DBG("Dispatching viewer request waiting on sock %d", conn
->sock
->fd
);
902 * Inform worker thread of the new request. This
903 * call is blocking so we can be assured that
904 * the data will be read at some point in time
905 * or wait to the end of the world :)
907 ret
= lttng_write(live_conn_pipe
[1], &conn
, sizeof(conn
)); /* NOLINT sizeof
911 PERROR("write conn pipe");
912 connection_put(conn
);
915 } while (node
!= nullptr);
917 /* Futex wait on queue. Blocking call on futex() */
919 futex_nto1_wait(&viewer_conn_queue
.futex
);
923 /* Normal exit, no error */
930 ERR("Health error occurred in %s", __func__
);
932 health_unregister(health_relayd
);
933 DBG("Live viewer dispatch thread dying");
934 if (lttng_relay_stop_threads()) {
935 ERR("Error stopping threads");
941 * Establish connection with the viewer and check the versions.
943 * Return 0 on success or else negative value.
945 static int viewer_connect(struct relay_connection
*conn
)
948 struct lttng_viewer_connect reply
, msg
;
950 conn
->version_check_done
= true;
952 health_code_update();
954 ret
= recv_request(conn
->sock
, &msg
, sizeof(msg
));
959 health_code_update();
961 memset(&reply
, 0, sizeof(reply
));
962 reply
.major
= RELAYD_VERSION_COMM_MAJOR
;
963 reply
.minor
= RELAYD_VERSION_COMM_MINOR
;
965 /* Major versions must be the same */
966 if (reply
.major
!= be32toh(msg
.major
)) {
967 DBG("Incompatible major versions ([relayd] %u vs [client] %u)",
974 conn
->major
= reply
.major
;
975 /* We adapt to the lowest compatible version */
976 if (reply
.minor
<= be32toh(msg
.minor
)) {
977 conn
->minor
= reply
.minor
;
979 conn
->minor
= be32toh(msg
.minor
);
982 if (be32toh(msg
.type
) == LTTNG_VIEWER_CLIENT_COMMAND
) {
983 conn
->type
= RELAY_VIEWER_COMMAND
;
984 } else if (be32toh(msg
.type
) == LTTNG_VIEWER_CLIENT_NOTIFICATION
) {
985 conn
->type
= RELAY_VIEWER_NOTIFICATION
;
987 ERR("Unknown connection type : %u", be32toh(msg
.type
));
992 reply
.major
= htobe32(reply
.major
);
993 reply
.minor
= htobe32(reply
.minor
);
994 if (conn
->type
== RELAY_VIEWER_COMMAND
) {
996 * Increment outside of htobe64 macro, because the argument can
997 * be used more than once within the macro, and thus the
998 * operation may be undefined.
1000 pthread_mutex_lock(&last_relay_viewer_session_id_lock
);
1001 last_relay_viewer_session_id
++;
1002 pthread_mutex_unlock(&last_relay_viewer_session_id_lock
);
1003 reply
.viewer_session_id
= htobe64(last_relay_viewer_session_id
);
1006 health_code_update();
1008 ret
= send_response(conn
->sock
, &reply
, sizeof(reply
));
1013 health_code_update();
1015 DBG("Version check done using protocol %u.%u", conn
->major
, conn
->minor
);
1023 * Send the viewer the list of current sessions.
1024 * We need to create a copy of the hash table content because otherwise
1025 * we cannot assume the number of entries stays the same between getting
1026 * the number of HT elements and iteration over the HT.
1028 * Return 0 on success or else a negative value.
1030 static int viewer_list_sessions(struct relay_connection
*conn
)
1033 struct lttng_viewer_list_sessions session_list
;
1034 struct lttng_ht_iter iter
;
1035 struct relay_session
*session
;
1036 struct lttng_viewer_session
*send_session_buf
= nullptr;
1037 uint32_t buf_count
= SESSION_BUF_DEFAULT_COUNT
;
1040 send_session_buf
= calloc
<lttng_viewer_session
>(SESSION_BUF_DEFAULT_COUNT
);
1041 if (!send_session_buf
) {
1046 cds_lfht_for_each_entry (sessions_ht
->ht
, &iter
.iter
, session
, session_n
.node
) {
1047 struct lttng_viewer_session
*send_session
;
1049 health_code_update();
1051 pthread_mutex_lock(&session
->lock
);
1052 if (session
->connection_closed
) {
1053 /* Skip closed session */
1057 if (count
>= buf_count
) {
1058 struct lttng_viewer_session
*newbuf
;
1059 uint32_t new_buf_count
= buf_count
<< 1;
1061 newbuf
= (lttng_viewer_session
*) realloc(
1062 send_session_buf
, new_buf_count
* sizeof(*send_session_buf
));
1067 send_session_buf
= newbuf
;
1068 buf_count
= new_buf_count
;
1070 send_session
= &send_session_buf
[count
];
1071 if (lttng_strncpy(send_session
->session_name
,
1072 session
->session_name
,
1073 sizeof(send_session
->session_name
))) {
1077 if (lttng_strncpy(send_session
->hostname
,
1079 sizeof(send_session
->hostname
))) {
1083 send_session
->id
= htobe64(session
->id
);
1084 send_session
->live_timer
= htobe32(session
->live_timer
);
1085 if (session
->viewer_attached
) {
1086 send_session
->clients
= htobe32(1);
1088 send_session
->clients
= htobe32(0);
1090 send_session
->streams
= htobe32(session
->stream_count
);
1093 pthread_mutex_unlock(&session
->lock
);
1096 pthread_mutex_unlock(&session
->lock
);
1104 session_list
.sessions_count
= htobe32(count
);
1106 health_code_update();
1108 ret
= send_response(conn
->sock
, &session_list
, sizeof(session_list
));
1113 health_code_update();
1115 ret
= send_response(conn
->sock
, send_session_buf
, count
* sizeof(*send_session_buf
));
1119 health_code_update();
1123 free(send_session_buf
);
1128 * Send the viewer the list of current streams.
1130 static int viewer_get_new_streams(struct relay_connection
*conn
)
1132 int ret
, send_streams
= 0;
1133 uint32_t nb_created
= 0, nb_unsent
= 0, nb_streams
= 0, nb_total
= 0;
1134 struct lttng_viewer_new_streams_request request
;
1135 struct lttng_viewer_new_streams_response response
;
1136 struct relay_session
*session
= nullptr;
1137 uint64_t session_id
;
1138 bool closed
= false;
1142 health_code_update();
1144 /* Receive the request from the connected client. */
1145 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
1149 session_id
= be64toh(request
.session_id
);
1151 health_code_update();
1153 memset(&response
, 0, sizeof(response
));
1155 session
= session_get_by_id(session_id
);
1157 DBG("Relay session %" PRIu64
" not found", session_id
);
1158 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR
);
1162 if (!viewer_session_is_attached(conn
->viewer_session
, session
)) {
1163 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR
);
1168 * For any new stream, create it with LTTNG_VIEWER_SEEK_BEGINNING since
1169 * that at this point the client is already attached to the session.Aany
1170 * initial stream will have been created with the seek type at attach
1171 * time (for now most readers use the LTTNG_VIEWER_SEEK_LAST on attach).
1172 * Otherwise any event happening in a new stream between the attach and
1173 * a call to viewer_get_new_streams will be "lost" (never received) from
1174 * the viewer's point of view.
1176 pthread_mutex_lock(&session
->lock
);
1178 * If a session rotation is ongoing, do not attempt to open any
1179 * stream, because the chunk can be in an intermediate state
1180 * due to directory renaming.
1182 if (session_has_ongoing_rotation(session
)) {
1183 DBG("Relay session %" PRIu64
" rotation ongoing", session_id
);
1184 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_NO_NEW
);
1185 goto send_reply_unlock
;
1187 ret
= make_viewer_streams(session
,
1188 conn
->viewer_session
,
1189 LTTNG_VIEWER_SEEK_BEGINNING
,
1196 * This is caused by an internal error; propagate the negative
1197 * 'ret' to close the connection.
1199 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR
);
1200 goto send_reply_unlock
;
1203 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_OK
);
1205 /* Only send back the newly created streams with the unsent ones. */
1206 nb_streams
= nb_created
+ nb_unsent
;
1207 response
.streams_count
= htobe32(nb_streams
);
1210 * If the session is closed, HUP when there are no more streams
1213 if (closed
&& nb_total
== 0) {
1215 response
.streams_count
= 0;
1216 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_HUP
);
1217 goto send_reply_unlock
;
1220 pthread_mutex_unlock(&session
->lock
);
1223 health_code_update();
1224 ret
= send_response(conn
->sock
, &response
, sizeof(response
));
1226 goto end_put_session
;
1228 health_code_update();
1231 * Unknown or empty session, just return gracefully, the viewer
1232 * knows what is happening.
1234 if (!send_streams
|| !nb_streams
) {
1236 goto end_put_session
;
1240 * Send stream and *DON'T* ignore the sent flag so every viewer
1241 * streams that were not sent from that point will be sent to
1244 ret
= send_viewer_streams(conn
->sock
, session_id
, 0);
1246 goto end_put_session
;
1251 session_put(session
);
1258 * Send the viewer the list of current sessions.
1260 static int viewer_attach_session(struct relay_connection
*conn
)
1262 int send_streams
= 0;
1264 uint32_t nb_streams
= 0;
1265 enum lttng_viewer_seek seek_type
;
1266 struct lttng_viewer_attach_session_request request
;
1267 struct lttng_viewer_attach_session_response response
;
1268 struct relay_session
*session
= nullptr;
1269 enum lttng_viewer_attach_return_code viewer_attach_status
;
1270 bool closed
= false;
1271 uint64_t session_id
;
1275 health_code_update();
1277 /* Receive the request from the connected client. */
1278 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
1283 session_id
= be64toh(request
.session_id
);
1285 health_code_update();
1287 memset(&response
, 0, sizeof(response
));
1289 if (!conn
->viewer_session
) {
1290 viewer_attach_status
= LTTNG_VIEWER_ATTACH_NO_SESSION
;
1291 DBG("Client trying to attach before creating a live viewer session, returning status=%s",
1292 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1296 session
= session_get_by_id(session_id
);
1298 viewer_attach_status
= LTTNG_VIEWER_ATTACH_UNK
;
1299 DBG("Relay session %" PRIu64
" not found, returning status=%s",
1301 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1304 DBG("Attach relay session ID %" PRIu64
" received", session_id
);
1306 pthread_mutex_lock(&session
->lock
);
1307 if (session
->live_timer
== 0) {
1308 viewer_attach_status
= LTTNG_VIEWER_ATTACH_NOT_LIVE
;
1309 DBG("Relay session ID %" PRIu64
" is not a live session, returning status=%s",
1311 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1316 viewer_attach_status
= viewer_session_attach(conn
->viewer_session
, session
);
1317 if (viewer_attach_status
!= LTTNG_VIEWER_ATTACH_OK
) {
1318 DBG("Error attaching to relay session %" PRIu64
", returning status=%s",
1320 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1324 switch (be32toh(request
.seek
)) {
1325 case LTTNG_VIEWER_SEEK_BEGINNING
:
1326 case LTTNG_VIEWER_SEEK_LAST
:
1327 viewer_attach_status
= LTTNG_VIEWER_ATTACH_OK
;
1328 seek_type
= (lttng_viewer_seek
) be32toh(request
.seek
);
1331 ERR("Wrong seek parameter for relay session %" PRIu64
", returning status=%s",
1333 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1334 viewer_attach_status
= LTTNG_VIEWER_ATTACH_SEEK_ERR
;
1340 * If a session rotation is ongoing, do not attempt to open any
1341 * stream, because the chunk can be in an intermediate state
1342 * due to directory renaming.
1344 if (session_has_ongoing_rotation(session
)) {
1345 DBG("Relay session %" PRIu64
" rotation ongoing", session_id
);
1350 ret
= make_viewer_streams(
1351 session
, conn
->viewer_session
, seek_type
, &nb_streams
, nullptr, nullptr, &closed
);
1353 goto end_put_session
;
1355 pthread_mutex_unlock(&session
->lock
);
1356 session_put(session
);
1359 response
.streams_count
= htobe32(nb_streams
);
1361 * If the session is closed when the viewer is attaching, it
1362 * means some of the streams may have been concurrently removed,
1363 * so we don't allow the viewer to attach, even if there are
1364 * streams available.
1368 response
.streams_count
= 0;
1369 viewer_attach_status
= LTTNG_VIEWER_ATTACH_UNK
;
1370 ERR("Session %" PRIu64
" is closed, returning status=%s",
1372 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1377 health_code_update();
1379 response
.status
= htobe32((uint32_t) viewer_attach_status
);
1381 ret
= send_response(conn
->sock
, &response
, sizeof(response
));
1383 goto end_put_session
;
1385 health_code_update();
1388 * Unknown or empty session, just return gracefully, the viewer
1389 * knows what is happening.
1391 if (!send_streams
|| !nb_streams
) {
1393 goto end_put_session
;
1396 /* Send stream and ignore the sent flag. */
1397 ret
= send_viewer_streams(conn
->sock
, session_id
, 1);
1399 goto end_put_session
;
1404 pthread_mutex_unlock(&session
->lock
);
1405 session_put(session
);
1412 * Open the index file if needed for the given vstream.
1414 * If an index file is successfully opened, the vstream will set it as its
1415 * current index file.
1417 * Return 0 on success, a negative value on error (-ENOENT if not ready yet).
1419 * Called with rstream lock held.
1421 static int try_open_index(struct relay_viewer_stream
*vstream
, struct relay_stream
*rstream
)
1424 const uint32_t connection_major
= rstream
->trace
->session
->major
;
1425 const uint32_t connection_minor
= rstream
->trace
->session
->minor
;
1426 enum lttng_trace_chunk_status chunk_status
;
1428 if (vstream
->index_file
) {
1433 * First time, we open the index file and at least one index is ready.
1435 if (rstream
->index_received_seqcount
== 0 || !vstream
->stream_file
.trace_chunk
) {
1440 chunk_status
= lttng_index_file_create_from_trace_chunk_read_only(
1441 vstream
->stream_file
.trace_chunk
,
1443 rstream
->channel_name
,
1444 rstream
->tracefile_size
,
1445 vstream
->current_tracefile_id
,
1446 lttng_to_index_major(connection_major
, connection_minor
),
1447 lttng_to_index_minor(connection_major
, connection_minor
),
1449 &vstream
->index_file
);
1450 if (chunk_status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
1451 if (chunk_status
== LTTNG_TRACE_CHUNK_STATUS_NO_FILE
) {
1463 * Check the status of the index for the given stream. This function
1464 * updates the index structure if needed and can put (close) the vstream
1465 * in the HUP situation.
1467 * Return 0 means that we can proceed with the index. A value of 1 means
1468 * that the index has been updated and is ready to be sent to the
1469 * client. A negative value indicates an error that can't be handled.
1471 * Called with rstream lock held.
1473 static int check_index_status(struct relay_viewer_stream
*vstream
,
1474 struct relay_stream
*rstream
,
1475 struct ctf_trace
*trace
,
1476 struct lttng_viewer_index
*index
)
1480 DBG("Check index status: index_received_seqcount %" PRIu64
" "
1481 "index_sent_seqcount %" PRIu64
" "
1482 "for stream %" PRIu64
,
1483 rstream
->index_received_seqcount
,
1484 vstream
->index_sent_seqcount
,
1485 vstream
->stream
->stream_handle
);
1486 if ((trace
->session
->connection_closed
|| rstream
->closed
) &&
1487 rstream
->index_received_seqcount
== vstream
->index_sent_seqcount
) {
1489 * Last index sent and session connection or relay
1490 * stream are closed.
1492 index
->status
= LTTNG_VIEWER_INDEX_HUP
;
1493 DBG("Check index status: Connection or stream are closed, stream %" PRIu64
1494 ",connection-closed=%d, relay-stream-closed=%d, returning status=%s",
1495 vstream
->stream
->stream_handle
,
1496 trace
->session
->connection_closed
,
1498 lttng_viewer_next_index_return_code_str(
1499 (enum lttng_viewer_next_index_return_code
) index
->status
));
1501 } else if (rstream
->beacon_ts_end
!= -1ULL &&
1502 (rstream
->index_received_seqcount
== 0 ||
1503 (vstream
->index_sent_seqcount
!= 0 &&
1504 rstream
->index_received_seqcount
<= vstream
->index_sent_seqcount
))) {
1506 * We've received a synchronization beacon and the last index
1507 * available has been sent, the index for now is inactive.
1509 * In this case, we have received a beacon which allows us to
1510 * inform the client of a time interval during which we can
1511 * guarantee that there are no events to read (and never will
1514 * The sent seqcount can grow higher than receive seqcount on
1515 * clear because the rotation performed by clear will push
1516 * the index_sent_seqcount ahead (see
1517 * viewer_stream_sync_tracefile_array_tail) and skip over
1518 * packet sequence numbers.
1520 index
->status
= LTTNG_VIEWER_INDEX_INACTIVE
;
1521 index
->timestamp_end
= htobe64(rstream
->beacon_ts_end
);
1522 index
->stream_id
= htobe64(rstream
->ctf_stream_id
);
1523 DBG("Check index status: inactive with beacon, for stream %" PRIu64
1524 ", returning status=%s",
1525 vstream
->stream
->stream_handle
,
1526 lttng_viewer_next_index_return_code_str(
1527 (enum lttng_viewer_next_index_return_code
) index
->status
));
1529 } else if (rstream
->index_received_seqcount
== 0 ||
1530 (vstream
->index_sent_seqcount
!= 0 &&
1531 rstream
->index_received_seqcount
<= vstream
->index_sent_seqcount
)) {
1533 * This checks whether received <= sent seqcount. In
1534 * this case, we have not received a beacon. Therefore,
1535 * we can only ask the client to retry later.
1537 * The sent seqcount can grow higher than receive seqcount on
1538 * clear because the rotation performed by clear will push
1539 * the index_sent_seqcount ahead (see
1540 * viewer_stream_sync_tracefile_array_tail) and skip over
1541 * packet sequence numbers.
1543 index
->status
= LTTNG_VIEWER_INDEX_RETRY
;
1544 DBG("Check index status:"
1545 "did not received beacon for stream %" PRIu64
", returning status=%s",
1546 vstream
->stream
->stream_handle
,
1547 lttng_viewer_next_index_return_code_str(
1548 (enum lttng_viewer_next_index_return_code
) index
->status
));
1550 } else if (!tracefile_array_seq_in_file(rstream
->tfa
,
1551 vstream
->current_tracefile_id
,
1552 vstream
->index_sent_seqcount
)) {
1554 * The next index we want to send cannot be read either
1555 * because we need to perform a rotation, or due to
1556 * the producer having overwritten its trace file.
1558 DBG("Viewer stream %" PRIu64
" rotation", vstream
->stream
->stream_handle
);
1559 ret
= viewer_stream_rotate(vstream
);
1561 /* EOF across entire stream. */
1562 index
->status
= LTTNG_VIEWER_INDEX_HUP
;
1563 DBG("Check index status:"
1564 "reached end of file for stream %" PRIu64
", returning status=%s",
1565 vstream
->stream
->stream_handle
,
1566 lttng_viewer_next_index_return_code_str(
1567 (enum lttng_viewer_next_index_return_code
) index
->status
));
1571 * If we have been pushed due to overwrite, it
1572 * necessarily means there is data that can be read in
1573 * the stream. If we rotated because we reached the end
1574 * of a tracefile, it means the following tracefile
1575 * needs to contain at least one index, else we would
1576 * have already returned LTTNG_VIEWER_INDEX_RETRY to the
1577 * viewer. The updated index_sent_seqcount needs to
1578 * point to a readable index entry now.
1580 * In the case where we "rotate" on a single file, we
1581 * can end up in a case where the requested index is
1582 * still unavailable.
1584 if (rstream
->tracefile_count
== 1 &&
1585 !tracefile_array_seq_in_file(rstream
->tfa
,
1586 vstream
->current_tracefile_id
,
1587 vstream
->index_sent_seqcount
)) {
1588 index
->status
= LTTNG_VIEWER_INDEX_RETRY
;
1589 DBG("Check index status:"
1590 "tracefile array sequence number %" PRIu64
1591 " not in file for stream %" PRIu64
", returning status=%s",
1592 vstream
->index_sent_seqcount
,
1593 vstream
->stream
->stream_handle
,
1594 lttng_viewer_next_index_return_code_str(
1595 (enum lttng_viewer_next_index_return_code
) index
->status
));
1598 LTTNG_ASSERT(tracefile_array_seq_in_file(
1599 rstream
->tfa
, vstream
->current_tracefile_id
, vstream
->index_sent_seqcount
));
1601 /* ret == 0 means successful so we continue. */
1606 viewer_stream_put(vstream
);
1611 static void viewer_stream_rotate_to_trace_chunk(struct relay_viewer_stream
*vstream
,
1612 struct lttng_trace_chunk
*new_trace_chunk
)
1614 lttng_trace_chunk_put(vstream
->stream_file
.trace_chunk
);
1616 if (new_trace_chunk
) {
1617 const bool acquired_reference
= lttng_trace_chunk_get(new_trace_chunk
);
1619 LTTNG_ASSERT(acquired_reference
);
1622 vstream
->stream_file
.trace_chunk
= new_trace_chunk
;
1623 viewer_stream_sync_tracefile_array_tail(vstream
);
1624 viewer_stream_close_files(vstream
);
1628 * Send the next index for a stream.
1630 * Return 0 on success or else a negative value.
1632 static int viewer_get_next_index(struct relay_connection
*conn
)
1635 struct lttng_viewer_get_next_index request_index
;
1636 struct lttng_viewer_index viewer_index
;
1637 struct ctf_packet_index packet_index
;
1638 struct relay_viewer_stream
*vstream
= nullptr;
1639 struct relay_stream
*rstream
= nullptr;
1640 struct ctf_trace
*ctf_trace
= nullptr;
1641 struct relay_viewer_stream
*metadata_viewer_stream
= nullptr;
1642 bool viewer_stream_and_session_in_same_chunk
, viewer_stream_one_rotation_behind
;
1643 uint64_t stream_file_chunk_id
= -1ULL, viewer_session_chunk_id
= -1ULL;
1644 enum lttng_trace_chunk_status status
;
1648 memset(&viewer_index
, 0, sizeof(viewer_index
));
1649 health_code_update();
1651 ret
= recv_request(conn
->sock
, &request_index
, sizeof(request_index
));
1655 health_code_update();
1657 vstream
= viewer_stream_get_by_id(be64toh(request_index
.stream_id
));
1659 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1660 DBG("Client requested index of unknown stream id %" PRIu64
", returning status=%s",
1661 (uint64_t) be64toh(request_index
.stream_id
),
1662 lttng_viewer_next_index_return_code_str(
1663 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1667 /* Use back. ref. Protected by refcounts. */
1668 rstream
= vstream
->stream
;
1669 ctf_trace
= rstream
->trace
;
1671 /* metadata_viewer_stream may be NULL. */
1672 metadata_viewer_stream
= ctf_trace_get_viewer_metadata_stream(ctf_trace
);
1675 * Hold the session lock to protect against concurrent changes
1676 * to the chunk files (e.g. rename done by clear), which are
1677 * protected by the session ongoing rotation state. Those are
1678 * synchronized with the session lock.
1680 pthread_mutex_lock(&rstream
->trace
->session
->lock
);
1681 pthread_mutex_lock(&rstream
->lock
);
1684 * The viewer should not ask for index on metadata stream.
1686 if (rstream
->is_metadata
) {
1687 viewer_index
.status
= LTTNG_VIEWER_INDEX_HUP
;
1688 DBG("Client requested index of a metadata stream id %" PRIu64
1689 ", returning status=%s",
1690 (uint64_t) be64toh(request_index
.stream_id
),
1691 lttng_viewer_next_index_return_code_str(
1692 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1696 if (rstream
->ongoing_rotation
.is_set
) {
1697 /* Rotation is ongoing, try again later. */
1698 viewer_index
.status
= LTTNG_VIEWER_INDEX_RETRY
;
1699 DBG("Client requested index for stream id %" PRIu64
1700 " while a stream rotation is ongoing, returning status=%s",
1701 (uint64_t) be64toh(request_index
.stream_id
),
1702 lttng_viewer_next_index_return_code_str(
1703 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1707 if (session_has_ongoing_rotation(rstream
->trace
->session
)) {
1708 /* Rotation is ongoing, try again later. */
1709 viewer_index
.status
= LTTNG_VIEWER_INDEX_RETRY
;
1710 DBG("Client requested index for stream id %" PRIu64
1711 " while a session rotation is ongoing, returning status=%s",
1712 (uint64_t) be64toh(request_index
.stream_id
),
1713 lttng_viewer_next_index_return_code_str(
1714 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1719 * Transition the viewer session into the newest trace chunk available.
1721 if (!lttng_trace_chunk_ids_equal(conn
->viewer_session
->current_trace_chunk
,
1722 rstream
->trace_chunk
)) {
1723 DBG("Relay stream and viewer chunk ids differ");
1725 ret
= viewer_session_set_trace_chunk_copy(conn
->viewer_session
,
1726 rstream
->trace_chunk
);
1728 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1729 ERR("Error copying trace chunk for stream id %" PRIu64
1730 ", returning status=%s",
1731 (uint64_t) be64toh(request_index
.stream_id
),
1732 lttng_viewer_next_index_return_code_str(
1733 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1739 * Transition the viewer stream into the latest trace chunk available.
1741 * Note that the stream must _not_ rotate in one precise condition:
1742 * the relay stream has rotated to a NULL trace chunk and the viewer
1743 * stream is consuming the trace chunk that was active just before
1744 * that rotation to NULL.
1746 * This allows clients to consume all the packets of a trace chunk
1747 * after a session's destruction.
1749 if (vstream
->stream_file
.trace_chunk
) {
1750 status
= lttng_trace_chunk_get_id(vstream
->stream_file
.trace_chunk
,
1751 &stream_file_chunk_id
);
1752 LTTNG_ASSERT(status
== LTTNG_TRACE_CHUNK_STATUS_OK
);
1754 if (conn
->viewer_session
->current_trace_chunk
) {
1755 status
= lttng_trace_chunk_get_id(conn
->viewer_session
->current_trace_chunk
,
1756 &viewer_session_chunk_id
);
1757 LTTNG_ASSERT(status
== LTTNG_TRACE_CHUNK_STATUS_OK
);
1760 viewer_stream_and_session_in_same_chunk
= lttng_trace_chunk_ids_equal(
1761 conn
->viewer_session
->current_trace_chunk
, vstream
->stream_file
.trace_chunk
);
1762 viewer_stream_one_rotation_behind
= rstream
->completed_rotation_count
==
1763 vstream
->last_seen_rotation_count
+ 1;
1765 if (viewer_stream_and_session_in_same_chunk
) {
1766 DBG("Transition to latest chunk check (%s -> %s): Same chunk, no need to rotate",
1767 vstream
->stream_file
.trace_chunk
?
1768 std::to_string(stream_file_chunk_id
).c_str() :
1770 conn
->viewer_session
->current_trace_chunk
?
1771 std::to_string(viewer_session_chunk_id
).c_str() :
1773 } else if (viewer_stream_one_rotation_behind
&& !rstream
->trace_chunk
) {
1774 DBG("Transition to latest chunk check (%s -> %s): One chunk behind relay stream which is being destroyed, no need to rotate",
1775 vstream
->stream_file
.trace_chunk
?
1776 std::to_string(stream_file_chunk_id
).c_str() :
1778 conn
->viewer_session
->current_trace_chunk
?
1779 std::to_string(viewer_session_chunk_id
).c_str() :
1782 DBG("Transition to latest chunk check (%s -> %s): Viewer stream chunk ID and viewer session chunk ID differ, rotating viewer stream",
1783 vstream
->stream_file
.trace_chunk
?
1784 std::to_string(stream_file_chunk_id
).c_str() :
1786 conn
->viewer_session
->current_trace_chunk
?
1787 std::to_string(viewer_session_chunk_id
).c_str() :
1790 viewer_stream_rotate_to_trace_chunk(vstream
,
1791 conn
->viewer_session
->current_trace_chunk
);
1792 vstream
->last_seen_rotation_count
= rstream
->completed_rotation_count
;
1795 ret
= check_index_status(vstream
, rstream
, ctf_trace
, &viewer_index
);
1798 } else if (ret
== 1) {
1800 * We have no index to send and check_index_status has populated
1801 * viewer_index's status.
1805 /* At this point, ret is 0 thus we will be able to read the index. */
1808 /* Try to open an index if one is needed for that stream. */
1809 ret
= try_open_index(vstream
, rstream
);
1810 if (ret
== -ENOENT
) {
1811 if (rstream
->closed
) {
1812 viewer_index
.status
= LTTNG_VIEWER_INDEX_HUP
;
1813 DBG("Cannot open index for stream id %" PRIu64
1814 "stream is closed, returning status=%s",
1815 (uint64_t) be64toh(request_index
.stream_id
),
1816 lttng_viewer_next_index_return_code_str(
1817 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1820 viewer_index
.status
= LTTNG_VIEWER_INDEX_RETRY
;
1821 DBG("Cannot open index for stream id %" PRIu64
", returning status=%s",
1822 (uint64_t) be64toh(request_index
.stream_id
),
1823 lttng_viewer_next_index_return_code_str(
1824 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1829 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1830 ERR("Error opening index for stream id %" PRIu64
", returning status=%s",
1831 (uint64_t) be64toh(request_index
.stream_id
),
1832 lttng_viewer_next_index_return_code_str(
1833 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1838 * vstream->stream_fd may be NULL if it has been closed by
1839 * tracefile rotation, or if we are at the beginning of the
1840 * stream. We open the data stream file here to protect against
1841 * overwrite caused by tracefile rotation (in association with
1842 * unlink performed before overwrite).
1844 if (!vstream
->stream_file
.handle
) {
1845 char file_path
[LTTNG_PATH_MAX
];
1846 struct fs_handle
*fs_handle
;
1848 ret
= utils_stream_file_path(rstream
->path_name
,
1849 rstream
->channel_name
,
1850 rstream
->tracefile_size
,
1851 vstream
->current_tracefile_id
,
1860 * It is possible the the file we are trying to open is
1861 * missing if the stream has been closed (application exits with
1862 * per-pid buffers) and a clear command has been performed.
1864 status
= lttng_trace_chunk_open_fs_handle(
1865 vstream
->stream_file
.trace_chunk
, file_path
, O_RDONLY
, 0, &fs_handle
, true);
1866 if (status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
1867 if (status
== LTTNG_TRACE_CHUNK_STATUS_NO_FILE
&& rstream
->closed
) {
1868 viewer_index
.status
= LTTNG_VIEWER_INDEX_HUP
;
1869 DBG("Cannot find trace chunk file and stream is closed for stream id %" PRIu64
1870 ", returning status=%s",
1871 (uint64_t) be64toh(request_index
.stream_id
),
1872 lttng_viewer_next_index_return_code_str(
1873 (enum lttng_viewer_next_index_return_code
)
1874 viewer_index
.status
));
1877 PERROR("Failed to open trace file for viewer stream");
1880 vstream
->stream_file
.handle
= fs_handle
;
1883 ret
= check_new_streams(conn
);
1885 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1886 ERR("Error checking for new streams before sending new index to stream id %" PRIu64
1887 ", returning status=%s",
1888 (uint64_t) be64toh(request_index
.stream_id
),
1889 lttng_viewer_next_index_return_code_str(
1890 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1892 } else if (ret
== 1) {
1893 viewer_index
.flags
|= LTTNG_VIEWER_FLAG_NEW_STREAM
;
1896 ret
= lttng_index_file_read(vstream
->index_file
, &packet_index
);
1898 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1899 ERR("Relay error reading index file for stream id %" PRIu64
", returning status=%s",
1900 (uint64_t) be64toh(request_index
.stream_id
),
1901 lttng_viewer_next_index_return_code_str(
1902 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1905 viewer_index
.status
= LTTNG_VIEWER_INDEX_OK
;
1906 DBG("Read index file for stream id %" PRIu64
", returning status=%s",
1907 (uint64_t) be64toh(request_index
.stream_id
),
1908 lttng_viewer_next_index_return_code_str(
1909 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1910 vstream
->index_sent_seqcount
++;
1914 * Indexes are stored in big endian, no need to switch before sending.
1916 DBG("Sending viewer index for stream %" PRIu64
" offset %" PRIu64
,
1917 rstream
->stream_handle
,
1918 (uint64_t) be64toh(packet_index
.offset
));
1919 viewer_index
.offset
= packet_index
.offset
;
1920 viewer_index
.packet_size
= packet_index
.packet_size
;
1921 viewer_index
.content_size
= packet_index
.content_size
;
1922 viewer_index
.timestamp_begin
= packet_index
.timestamp_begin
;
1923 viewer_index
.timestamp_end
= packet_index
.timestamp_end
;
1924 viewer_index
.events_discarded
= packet_index
.events_discarded
;
1925 viewer_index
.stream_id
= packet_index
.stream_id
;
1929 pthread_mutex_unlock(&rstream
->lock
);
1930 pthread_mutex_unlock(&rstream
->trace
->session
->lock
);
1933 if (metadata_viewer_stream
) {
1934 pthread_mutex_lock(&metadata_viewer_stream
->stream
->lock
);
1935 DBG("get next index metadata check: recv %" PRIu64
" sent %" PRIu64
,
1936 metadata_viewer_stream
->stream
->metadata_received
,
1937 metadata_viewer_stream
->metadata_sent
);
1938 if (!metadata_viewer_stream
->stream
->metadata_received
||
1939 metadata_viewer_stream
->stream
->metadata_received
>
1940 metadata_viewer_stream
->metadata_sent
) {
1941 viewer_index
.flags
|= LTTNG_VIEWER_FLAG_NEW_METADATA
;
1943 pthread_mutex_unlock(&metadata_viewer_stream
->stream
->lock
);
1946 viewer_index
.flags
= htobe32(viewer_index
.flags
);
1947 viewer_index
.status
= htobe32(viewer_index
.status
);
1948 health_code_update();
1950 ret
= send_response(conn
->sock
, &viewer_index
, sizeof(viewer_index
));
1954 health_code_update();
1957 DBG("Index %" PRIu64
" for stream %" PRIu64
" sent",
1958 vstream
->index_sent_seqcount
,
1959 vstream
->stream
->stream_handle
);
1962 if (metadata_viewer_stream
) {
1963 viewer_stream_put(metadata_viewer_stream
);
1966 viewer_stream_put(vstream
);
1971 pthread_mutex_unlock(&rstream
->lock
);
1972 pthread_mutex_unlock(&rstream
->trace
->session
->lock
);
1973 if (metadata_viewer_stream
) {
1974 viewer_stream_put(metadata_viewer_stream
);
1976 viewer_stream_put(vstream
);
1981 * Send the next index for a stream
1983 * Return 0 on success or else a negative value.
1985 static int viewer_get_packet(struct relay_connection
*conn
)
1989 char *reply
= nullptr;
1990 struct lttng_viewer_get_packet get_packet_info
;
1991 struct lttng_viewer_trace_packet reply_header
;
1992 struct relay_viewer_stream
*vstream
= nullptr;
1993 uint32_t reply_size
= sizeof(reply_header
);
1994 uint32_t packet_data_len
= 0;
1997 enum lttng_viewer_get_packet_return_code get_packet_status
;
1999 health_code_update();
2001 ret
= recv_request(conn
->sock
, &get_packet_info
, sizeof(get_packet_info
));
2005 health_code_update();
2007 /* From this point on, the error label can be reached. */
2008 memset(&reply_header
, 0, sizeof(reply_header
));
2009 stream_id
= (uint64_t) be64toh(get_packet_info
.stream_id
);
2011 vstream
= viewer_stream_get_by_id(stream_id
);
2013 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2014 DBG("Client requested packet of unknown stream id %" PRIu64
", returning status=%s",
2016 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2017 goto send_reply_nolock
;
2019 packet_data_len
= be32toh(get_packet_info
.len
);
2020 reply_size
+= packet_data_len
;
2023 reply
= zmalloc
<char>(reply_size
);
2025 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2026 PERROR("Falled to allocate reply, returning status=%s",
2027 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2031 pthread_mutex_lock(&vstream
->stream
->lock
);
2032 lseek_ret
= fs_handle_seek(
2033 vstream
->stream_file
.handle
, be64toh(get_packet_info
.offset
), SEEK_SET
);
2034 if (lseek_ret
< 0) {
2035 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2036 PERROR("Failed to seek file system handle of viewer stream %" PRIu64
2037 " to offset %" PRIu64
", returning status=%s",
2039 (uint64_t) be64toh(get_packet_info
.offset
),
2040 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2043 read_len
= fs_handle_read(
2044 vstream
->stream_file
.handle
, reply
+ sizeof(reply_header
), packet_data_len
);
2045 if (read_len
< packet_data_len
) {
2046 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2047 PERROR("Failed to read from file system handle of viewer stream id %" PRIu64
2048 ", offset: %" PRIu64
", returning status=%s",
2050 (uint64_t) be64toh(get_packet_info
.offset
),
2051 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2055 get_packet_status
= LTTNG_VIEWER_GET_PACKET_OK
;
2056 reply_header
.len
= htobe32(packet_data_len
);
2060 /* No payload to send on error. */
2061 reply_size
= sizeof(reply_header
);
2065 pthread_mutex_unlock(&vstream
->stream
->lock
);
2069 health_code_update();
2071 reply_header
.status
= htobe32(get_packet_status
);
2073 memcpy(reply
, &reply_header
, sizeof(reply_header
));
2074 ret
= send_response(conn
->sock
, reply
, reply_size
);
2076 /* No reply to send. */
2077 ret
= send_response(conn
->sock
, &reply_header
, reply_size
);
2080 health_code_update();
2082 PERROR("sendmsg of packet data failed");
2086 DBG("Sent %u bytes for stream %" PRIu64
, reply_size
, stream_id
);
2092 viewer_stream_put(vstream
);
2098 * Send the session's metadata
2100 * Return 0 on success else a negative value.
2102 static int viewer_get_metadata(struct relay_connection
*conn
)
2108 char *data
= nullptr;
2109 struct lttng_viewer_get_metadata request
;
2110 struct lttng_viewer_metadata_packet reply
;
2111 struct relay_viewer_stream
*vstream
= nullptr;
2115 health_code_update();
2117 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
2121 health_code_update();
2123 memset(&reply
, 0, sizeof(reply
));
2125 vstream
= viewer_stream_get_by_id(be64toh(request
.stream_id
));
2128 * The metadata stream can be closed by a CLOSE command
2129 * just before we attach. It can also be closed by
2130 * per-pid tracing during tracing. Therefore, it is
2131 * possible that we cannot find this viewer stream.
2132 * Reply back to the client with an error if we cannot
2135 DBG("Client requested metadata of unknown stream id %" PRIu64
,
2136 (uint64_t) be64toh(request
.stream_id
));
2137 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2140 pthread_mutex_lock(&vstream
->stream
->lock
);
2141 if (!vstream
->stream
->is_metadata
) {
2142 ERR("Invalid metadata stream");
2146 if (vstream
->metadata_sent
>= vstream
->stream
->metadata_received
) {
2148 * The live viewers expect to receive a NO_NEW_METADATA
2149 * status before a stream disappears, otherwise they abort the
2150 * entire live connection when receiving an error status.
2152 * Clear feature resets the metadata_sent to 0 until the
2153 * same metadata is received again.
2155 reply
.status
= htobe32(LTTNG_VIEWER_NO_NEW_METADATA
);
2157 * The live viewer considers a closed 0 byte metadata stream as
2160 if (vstream
->metadata_sent
> 0) {
2161 if (vstream
->stream
->closed
&& vstream
->stream
->no_new_metadata_notified
) {
2163 * Release ownership for the viewer metadata
2164 * stream. Note that this reference is the
2165 * viewer's reference. The vstream still exists
2166 * until the end of the function as
2167 * viewer_stream_get_by_id() took a reference.
2169 viewer_stream_put(vstream
);
2172 vstream
->stream
->no_new_metadata_notified
= true;
2177 if (vstream
->stream
->trace_chunk
&&
2178 !lttng_trace_chunk_ids_equal(conn
->viewer_session
->current_trace_chunk
,
2179 vstream
->stream
->trace_chunk
)) {
2180 /* A rotation has occurred on the relay stream. */
2181 DBG("Metadata relay stream and viewer chunk ids differ");
2183 ret
= viewer_session_set_trace_chunk_copy(conn
->viewer_session
,
2184 vstream
->stream
->trace_chunk
);
2186 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2191 if (conn
->viewer_session
->current_trace_chunk
&&
2192 !lttng_trace_chunk_ids_equal(conn
->viewer_session
->current_trace_chunk
,
2193 vstream
->stream_file
.trace_chunk
)) {
2194 bool acquired_reference
;
2196 DBG("Viewer session and viewer stream chunk differ: "
2197 "vsession chunk %p vstream chunk %p",
2198 conn
->viewer_session
->current_trace_chunk
,
2199 vstream
->stream_file
.trace_chunk
);
2200 lttng_trace_chunk_put(vstream
->stream_file
.trace_chunk
);
2201 acquired_reference
=
2202 lttng_trace_chunk_get(conn
->viewer_session
->current_trace_chunk
);
2203 LTTNG_ASSERT(acquired_reference
);
2204 vstream
->stream_file
.trace_chunk
= conn
->viewer_session
->current_trace_chunk
;
2205 viewer_stream_close_files(vstream
);
2208 len
= vstream
->stream
->metadata_received
- vstream
->metadata_sent
;
2210 if (!vstream
->stream_file
.trace_chunk
) {
2211 reply
.status
= htobe32(LTTNG_VIEWER_NO_NEW_METADATA
);
2214 } else if (vstream
->stream_file
.trace_chunk
&& !vstream
->stream_file
.handle
&& len
> 0) {
2216 * Either this is the first time the metadata file is read, or a
2217 * rotation of the corresponding relay stream has occurred.
2219 struct fs_handle
*fs_handle
;
2220 char file_path
[LTTNG_PATH_MAX
];
2221 enum lttng_trace_chunk_status status
;
2222 struct relay_stream
*rstream
= vstream
->stream
;
2224 ret
= utils_stream_file_path(rstream
->path_name
,
2225 rstream
->channel_name
,
2226 rstream
->tracefile_size
,
2227 vstream
->current_tracefile_id
,
2236 * It is possible the the metadata file we are trying to open is
2237 * missing if the stream has been closed (application exits with
2238 * per-pid buffers) and a clear command has been performed.
2240 status
= lttng_trace_chunk_open_fs_handle(
2241 vstream
->stream_file
.trace_chunk
, file_path
, O_RDONLY
, 0, &fs_handle
, true);
2242 if (status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
2243 if (status
== LTTNG_TRACE_CHUNK_STATUS_NO_FILE
) {
2244 reply
.status
= htobe32(LTTNG_VIEWER_NO_NEW_METADATA
);
2246 if (vstream
->stream
->closed
) {
2247 viewer_stream_put(vstream
);
2251 PERROR("Failed to open metadata file for viewer stream");
2254 vstream
->stream_file
.handle
= fs_handle
;
2256 if (vstream
->metadata_sent
!= 0) {
2258 * The client does not expect to receive any metadata
2259 * it has received and metadata files in successive
2260 * chunks must be a strict superset of one another.
2262 * Skip the first `metadata_sent` bytes to ensure
2263 * they are not sent a second time to the client.
2265 * Baring a block layer error or an internal error,
2266 * this seek should not fail as
2267 * `vstream->stream->metadata_received` is reset when
2268 * a relay stream is rotated. If this is reached, it is
2269 * safe to assume that
2270 * `metadata_received` > `metadata_sent`.
2272 const off_t seek_ret
=
2273 fs_handle_seek(fs_handle
, vstream
->metadata_sent
, SEEK_SET
);
2276 PERROR("Failed to seek metadata viewer stream file to `sent` position: pos = %" PRId64
,
2277 vstream
->metadata_sent
);
2278 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2284 reply
.len
= htobe64(len
);
2285 data
= zmalloc
<char>(len
);
2287 PERROR("viewer metadata zmalloc");
2291 fd
= fs_handle_get_fd(vstream
->stream_file
.handle
);
2293 ERR("Failed to restore viewer stream file system handle");
2296 read_len
= lttng_read(fd
, data
, len
);
2297 fs_handle_put_fd(vstream
->stream_file
.handle
);
2299 if (read_len
< len
) {
2301 PERROR("Failed to read metadata file");
2305 * A clear has been performed which prevents the relay
2306 * from sending `len` bytes of metadata.
2308 * It is important not to send any metadata if we
2309 * couldn't read all the available metadata in one shot:
2310 * sending partial metadata can cause the client to
2311 * attempt to parse an incomplete (incoherent) metadata
2312 * stream, which would result in an error.
2314 const off_t seek_ret
=
2315 fs_handle_seek(vstream
->stream_file
.handle
, -read_len
, SEEK_CUR
);
2317 DBG("Failed to read metadata: requested = %" PRIu64
", got = %zd",
2323 PERROR("Failed to restore metadata file position after partial read");
2329 vstream
->metadata_sent
+= read_len
;
2330 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_OK
);
2335 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2338 health_code_update();
2340 pthread_mutex_unlock(&vstream
->stream
->lock
);
2342 ret
= send_response(conn
->sock
, &reply
, sizeof(reply
));
2346 health_code_update();
2349 ret
= send_response(conn
->sock
, data
, len
);
2355 DBG("Sent %" PRIu64
" bytes of metadata for stream %" PRIu64
,
2357 (uint64_t) be64toh(request
.stream_id
));
2359 DBG("Metadata sent");
2365 viewer_stream_put(vstream
);
2371 * Create a viewer session.
2373 * Return 0 on success or else a negative value.
2375 static int viewer_create_session(struct relay_connection
*conn
)
2378 struct lttng_viewer_create_session_response resp
;
2380 memset(&resp
, 0, sizeof(resp
));
2381 resp
.status
= htobe32(LTTNG_VIEWER_CREATE_SESSION_OK
);
2382 conn
->viewer_session
= viewer_session_create();
2383 if (!conn
->viewer_session
) {
2384 ERR("Allocation viewer session");
2385 resp
.status
= htobe32(LTTNG_VIEWER_CREATE_SESSION_ERR
);
2390 health_code_update();
2391 ret
= send_response(conn
->sock
, &resp
, sizeof(resp
));
2395 health_code_update();
2403 * Detach a viewer session.
2405 * Return 0 on success or else a negative value.
2407 static int viewer_detach_session(struct relay_connection
*conn
)
2410 struct lttng_viewer_detach_session_response response
;
2411 struct lttng_viewer_detach_session_request request
;
2412 struct relay_session
*session
= nullptr;
2413 uint64_t viewer_session_to_close
;
2417 health_code_update();
2419 /* Receive the request from the connected client. */
2420 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
2424 viewer_session_to_close
= be64toh(request
.session_id
);
2426 if (!conn
->viewer_session
) {
2427 DBG("Client trying to detach before creating a live viewer session");
2428 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR
);
2432 health_code_update();
2434 memset(&response
, 0, sizeof(response
));
2435 DBG("Detaching from session ID %" PRIu64
, viewer_session_to_close
);
2437 session
= session_get_by_id(be64toh(request
.session_id
));
2439 DBG("Relay session %" PRIu64
" not found", (uint64_t) be64toh(request
.session_id
));
2440 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_UNK
);
2444 ret
= viewer_session_is_attached(conn
->viewer_session
, session
);
2446 DBG("Not attached to this session");
2447 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR
);
2448 goto send_reply_put
;
2451 viewer_session_close_one_session(conn
->viewer_session
, session
);
2452 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_OK
);
2453 DBG("Session %" PRIu64
" detached.", viewer_session_to_close
);
2456 session_put(session
);
2459 health_code_update();
2460 ret
= send_response(conn
->sock
, &response
, sizeof(response
));
2464 health_code_update();
2472 * live_relay_unknown_command: send -1 if received unknown command
2474 static void live_relay_unknown_command(struct relay_connection
*conn
)
2476 struct lttcomm_relayd_generic_reply reply
;
2478 memset(&reply
, 0, sizeof(reply
));
2479 reply
.ret_code
= htobe32(LTTNG_ERR_UNK
);
2480 (void) send_response(conn
->sock
, &reply
, sizeof(reply
));
2484 * Process the commands received on the control socket
2486 static int process_control(struct lttng_viewer_cmd
*recv_hdr
, struct relay_connection
*conn
)
2489 lttng_viewer_command cmd
= (lttng_viewer_command
) be32toh(recv_hdr
->cmd
);
2492 * Make sure we've done the version check before any command other then
2493 * a new client connection.
2495 if (cmd
!= LTTNG_VIEWER_CONNECT
&& !conn
->version_check_done
) {
2496 ERR("Viewer on connection %d requested %s command before version check",
2498 lttng_viewer_command_str(cmd
));
2503 DBG("Processing %s viewer command from connection %d",
2504 lttng_viewer_command_str(cmd
),
2508 case LTTNG_VIEWER_CONNECT
:
2509 ret
= viewer_connect(conn
);
2511 case LTTNG_VIEWER_LIST_SESSIONS
:
2512 ret
= viewer_list_sessions(conn
);
2514 case LTTNG_VIEWER_ATTACH_SESSION
:
2515 ret
= viewer_attach_session(conn
);
2517 case LTTNG_VIEWER_GET_NEXT_INDEX
:
2518 ret
= viewer_get_next_index(conn
);
2520 case LTTNG_VIEWER_GET_PACKET
:
2521 ret
= viewer_get_packet(conn
);
2523 case LTTNG_VIEWER_GET_METADATA
:
2524 ret
= viewer_get_metadata(conn
);
2526 case LTTNG_VIEWER_GET_NEW_STREAMS
:
2527 ret
= viewer_get_new_streams(conn
);
2529 case LTTNG_VIEWER_CREATE_SESSION
:
2530 ret
= viewer_create_session(conn
);
2532 case LTTNG_VIEWER_DETACH_SESSION
:
2533 ret
= viewer_detach_session(conn
);
2536 ERR("Received unknown viewer command (%u)", be32toh(recv_hdr
->cmd
));
2537 live_relay_unknown_command(conn
);
2546 static void cleanup_connection_pollfd(struct lttng_poll_event
*events
, int pollfd
)
2550 (void) lttng_poll_del(events
, pollfd
);
2552 ret
= fd_tracker_close_unsuspendable_fd(
2553 the_fd_tracker
, &pollfd
, 1, fd_tracker_util_close_fd
, nullptr);
2555 ERR("Closing pollfd %d", pollfd
);
2560 * This thread does the actual work
2562 static void *thread_worker(void *data
__attribute__((unused
)))
2566 struct lttng_poll_event events
;
2567 struct lttng_ht
*viewer_connections_ht
;
2568 struct lttng_ht_iter iter
;
2569 struct lttng_viewer_cmd recv_hdr
;
2570 struct relay_connection
*destroy_conn
;
2572 DBG("[thread] Live viewer relay worker started");
2574 rcu_register_thread();
2576 health_register(health_relayd
, HEALTH_RELAYD_TYPE_LIVE_WORKER
);
2578 if (testpoint(relayd_thread_live_worker
)) {
2579 goto error_testpoint
;
2582 /* table of connections indexed on socket */
2583 viewer_connections_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
2584 if (!viewer_connections_ht
) {
2585 goto viewer_connections_ht_error
;
2588 ret
= create_named_thread_poll_set(&events
, 2, "Live viewer worker thread epoll");
2590 goto error_poll_create
;
2593 ret
= lttng_poll_add(&events
, live_conn_pipe
[0], LPOLLIN
| LPOLLRDHUP
);
2602 health_code_update();
2604 /* Infinite blocking call, waiting for transmission */
2605 DBG3("Relayd live viewer worker thread polling...");
2606 health_poll_entry();
2607 ret
= lttng_poll_wait(&events
, -1);
2611 * Restart interrupted system call.
2613 if (errno
== EINTR
) {
2622 * Process control. The control connection is prioritised so we don't
2623 * starve it with high throughput tracing data on the data
2626 for (i
= 0; i
< nb_fd
; i
++) {
2627 /* Fetch once the poll data */
2628 const auto revents
= LTTNG_POLL_GETEV(&events
, i
);
2629 const auto pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2631 health_code_update();
2633 /* Activity on thread quit pipe, exiting. */
2634 if (relayd_is_thread_quit_pipe(pollfd
)) {
2635 DBG("Activity on thread quit pipe");
2640 /* Inspect the relay conn pipe for new connection. */
2641 if (pollfd
== live_conn_pipe
[0]) {
2642 if (revents
& LPOLLIN
) {
2643 struct relay_connection
*conn
;
2645 ret
= lttng_read(live_conn_pipe
[0],
2647 sizeof(conn
)); /* NOLINT sizeof used on a
2652 ret
= lttng_poll_add(
2653 &events
, conn
->sock
->fd
, LPOLLIN
| LPOLLRDHUP
);
2655 ERR("Failed to add new live connection file descriptor to poll set");
2658 connection_ht_add(viewer_connections_ht
, conn
);
2659 DBG("Connection socket %d added to poll", conn
->sock
->fd
);
2660 } else if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2661 ERR("Relay live pipe error");
2664 ERR("Unexpected poll events %u for sock %d",
2670 /* Connection activity. */
2671 struct relay_connection
*conn
;
2673 conn
= connection_get_by_sock(viewer_connections_ht
, pollfd
);
2678 if (revents
& LPOLLIN
) {
2679 ret
= conn
->sock
->ops
->recvmsg(
2680 conn
->sock
, &recv_hdr
, sizeof(recv_hdr
), 0);
2682 /* Connection closed. */
2683 cleanup_connection_pollfd(&events
, pollfd
);
2684 /* Put "create" ownership reference. */
2685 connection_put(conn
);
2686 DBG("Viewer control conn closed with %d", pollfd
);
2688 ret
= process_control(&recv_hdr
, conn
);
2690 /* Clear the session on error. */
2691 cleanup_connection_pollfd(&events
, pollfd
);
2692 /* Put "create" ownership reference. */
2693 connection_put(conn
);
2694 DBG("Viewer connection closed with %d",
2698 } else if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2699 cleanup_connection_pollfd(&events
, pollfd
);
2700 /* Put "create" ownership reference. */
2701 connection_put(conn
);
2703 ERR("Unexpected poll events %u for sock %d",
2706 connection_put(conn
);
2709 /* Put local "get_by_sock" reference. */
2710 connection_put(conn
);
2717 (void) fd_tracker_util_poll_clean(the_fd_tracker
, &events
);
2719 /* Cleanup remaining connection object. */
2721 cds_lfht_for_each_entry (viewer_connections_ht
->ht
, &iter
.iter
, destroy_conn
, sock_n
.node
) {
2722 health_code_update();
2723 connection_put(destroy_conn
);
2727 lttng_ht_destroy(viewer_connections_ht
);
2728 viewer_connections_ht_error
:
2729 /* Close relay conn pipes */
2730 (void) fd_tracker_util_pipe_close(the_fd_tracker
, live_conn_pipe
);
2732 DBG("Viewer worker thread exited with error");
2734 DBG("Viewer worker thread cleanup complete");
2738 ERR("Health error occurred in %s", __func__
);
2740 health_unregister(health_relayd
);
2741 if (lttng_relay_stop_threads()) {
2742 ERR("Error stopping threads");
2744 rcu_unregister_thread();
2749 * Create the relay command pipe to wake thread_manage_apps.
2750 * Closed in cleanup().
2752 static int create_conn_pipe()
2754 return fd_tracker_util_pipe_open_cloexec(
2755 the_fd_tracker
, "Live connection pipe", live_conn_pipe
);
2758 int relayd_live_join()
2760 int ret
, retval
= 0;
2763 ret
= pthread_join(live_listener_thread
, &status
);
2766 PERROR("pthread_join live listener");
2770 ret
= pthread_join(live_worker_thread
, &status
);
2773 PERROR("pthread_join live worker");
2777 ret
= pthread_join(live_dispatcher_thread
, &status
);
2780 PERROR("pthread_join live dispatcher");
2784 cleanup_relayd_live();
2792 int relayd_live_create(struct lttng_uri
*uri
)
2794 int ret
= 0, retval
= 0;
2800 goto exit_init_data
;
2804 /* Check if daemon is UID = 0 */
2805 is_root
= !getuid();
2808 if (live_uri
->port
< 1024) {
2809 ERR("Need to be root to use ports < 1024");
2811 goto exit_init_data
;
2815 /* Setup the thread apps communication pipe. */
2816 if (create_conn_pipe()) {
2818 goto exit_init_data
;
2821 /* Init relay command queue. */
2822 cds_wfcq_init(&viewer_conn_queue
.head
, &viewer_conn_queue
.tail
);
2824 /* Set up max poll set size */
2825 if (lttng_poll_set_max_size()) {
2827 goto exit_init_data
;
2830 /* Setup the dispatcher thread */
2831 ret
= pthread_create(&live_dispatcher_thread
,
2832 default_pthread_attr(),
2837 PERROR("pthread_create viewer dispatcher");
2839 goto exit_dispatcher_thread
;
2842 /* Setup the worker thread */
2843 ret
= pthread_create(&live_worker_thread
, default_pthread_attr(), thread_worker
, nullptr);
2846 PERROR("pthread_create viewer worker");
2848 goto exit_worker_thread
;
2851 /* Setup the listener thread */
2852 ret
= pthread_create(
2853 &live_listener_thread
, default_pthread_attr(), thread_listener
, (void *) nullptr);
2856 PERROR("pthread_create viewer listener");
2858 goto exit_listener_thread
;
2862 * All OK, started all threads.
2867 * Join on the live_listener_thread should anything be added after
2868 * the live_listener thread's creation.
2871 exit_listener_thread
:
2873 ret
= pthread_join(live_worker_thread
, &status
);
2876 PERROR("pthread_join live worker");
2881 ret
= pthread_join(live_dispatcher_thread
, &status
);
2884 PERROR("pthread_join live dispatcher");
2887 exit_dispatcher_thread
:
2890 cleanup_relayd_live();