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
));
909 PERROR("write conn pipe");
910 connection_put(conn
);
913 } while (node
!= nullptr);
915 /* Futex wait on queue. Blocking call on futex() */
917 futex_nto1_wait(&viewer_conn_queue
.futex
);
921 /* Normal exit, no error */
928 ERR("Health error occurred in %s", __func__
);
930 health_unregister(health_relayd
);
931 DBG("Live viewer dispatch thread dying");
932 if (lttng_relay_stop_threads()) {
933 ERR("Error stopping threads");
939 * Establish connection with the viewer and check the versions.
941 * Return 0 on success or else negative value.
943 static int viewer_connect(struct relay_connection
*conn
)
946 struct lttng_viewer_connect reply
, msg
;
948 conn
->version_check_done
= true;
950 health_code_update();
952 ret
= recv_request(conn
->sock
, &msg
, sizeof(msg
));
957 health_code_update();
959 memset(&reply
, 0, sizeof(reply
));
960 reply
.major
= RELAYD_VERSION_COMM_MAJOR
;
961 reply
.minor
= RELAYD_VERSION_COMM_MINOR
;
963 /* Major versions must be the same */
964 if (reply
.major
!= be32toh(msg
.major
)) {
965 DBG("Incompatible major versions ([relayd] %u vs [client] %u)",
972 conn
->major
= reply
.major
;
973 /* We adapt to the lowest compatible version */
974 if (reply
.minor
<= be32toh(msg
.minor
)) {
975 conn
->minor
= reply
.minor
;
977 conn
->minor
= be32toh(msg
.minor
);
980 if (be32toh(msg
.type
) == LTTNG_VIEWER_CLIENT_COMMAND
) {
981 conn
->type
= RELAY_VIEWER_COMMAND
;
982 } else if (be32toh(msg
.type
) == LTTNG_VIEWER_CLIENT_NOTIFICATION
) {
983 conn
->type
= RELAY_VIEWER_NOTIFICATION
;
985 ERR("Unknown connection type : %u", be32toh(msg
.type
));
990 reply
.major
= htobe32(reply
.major
);
991 reply
.minor
= htobe32(reply
.minor
);
992 if (conn
->type
== RELAY_VIEWER_COMMAND
) {
994 * Increment outside of htobe64 macro, because the argument can
995 * be used more than once within the macro, and thus the
996 * operation may be undefined.
998 pthread_mutex_lock(&last_relay_viewer_session_id_lock
);
999 last_relay_viewer_session_id
++;
1000 pthread_mutex_unlock(&last_relay_viewer_session_id_lock
);
1001 reply
.viewer_session_id
= htobe64(last_relay_viewer_session_id
);
1004 health_code_update();
1006 ret
= send_response(conn
->sock
, &reply
, sizeof(reply
));
1011 health_code_update();
1013 DBG("Version check done using protocol %u.%u", conn
->major
, conn
->minor
);
1021 * Send the viewer the list of current sessions.
1022 * We need to create a copy of the hash table content because otherwise
1023 * we cannot assume the number of entries stays the same between getting
1024 * the number of HT elements and iteration over the HT.
1026 * Return 0 on success or else a negative value.
1028 static int viewer_list_sessions(struct relay_connection
*conn
)
1031 struct lttng_viewer_list_sessions session_list
;
1032 struct lttng_ht_iter iter
;
1033 struct relay_session
*session
;
1034 struct lttng_viewer_session
*send_session_buf
= nullptr;
1035 uint32_t buf_count
= SESSION_BUF_DEFAULT_COUNT
;
1038 send_session_buf
= calloc
<lttng_viewer_session
>(SESSION_BUF_DEFAULT_COUNT
);
1039 if (!send_session_buf
) {
1044 cds_lfht_for_each_entry (sessions_ht
->ht
, &iter
.iter
, session
, session_n
.node
) {
1045 struct lttng_viewer_session
*send_session
;
1047 health_code_update();
1049 pthread_mutex_lock(&session
->lock
);
1050 if (session
->connection_closed
) {
1051 /* Skip closed session */
1055 if (count
>= buf_count
) {
1056 struct lttng_viewer_session
*newbuf
;
1057 uint32_t new_buf_count
= buf_count
<< 1;
1059 newbuf
= (lttng_viewer_session
*) realloc(
1060 send_session_buf
, new_buf_count
* sizeof(*send_session_buf
));
1065 send_session_buf
= newbuf
;
1066 buf_count
= new_buf_count
;
1068 send_session
= &send_session_buf
[count
];
1069 if (lttng_strncpy(send_session
->session_name
,
1070 session
->session_name
,
1071 sizeof(send_session
->session_name
))) {
1075 if (lttng_strncpy(send_session
->hostname
,
1077 sizeof(send_session
->hostname
))) {
1081 send_session
->id
= htobe64(session
->id
);
1082 send_session
->live_timer
= htobe32(session
->live_timer
);
1083 if (session
->viewer_attached
) {
1084 send_session
->clients
= htobe32(1);
1086 send_session
->clients
= htobe32(0);
1088 send_session
->streams
= htobe32(session
->stream_count
);
1091 pthread_mutex_unlock(&session
->lock
);
1094 pthread_mutex_unlock(&session
->lock
);
1102 session_list
.sessions_count
= htobe32(count
);
1104 health_code_update();
1106 ret
= send_response(conn
->sock
, &session_list
, sizeof(session_list
));
1111 health_code_update();
1113 ret
= send_response(conn
->sock
, send_session_buf
, count
* sizeof(*send_session_buf
));
1117 health_code_update();
1121 free(send_session_buf
);
1126 * Send the viewer the list of current streams.
1128 static int viewer_get_new_streams(struct relay_connection
*conn
)
1130 int ret
, send_streams
= 0;
1131 uint32_t nb_created
= 0, nb_unsent
= 0, nb_streams
= 0, nb_total
= 0;
1132 struct lttng_viewer_new_streams_request request
;
1133 struct lttng_viewer_new_streams_response response
;
1134 struct relay_session
*session
= nullptr;
1135 uint64_t session_id
;
1136 bool closed
= false;
1140 health_code_update();
1142 /* Receive the request from the connected client. */
1143 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
1147 session_id
= be64toh(request
.session_id
);
1149 health_code_update();
1151 memset(&response
, 0, sizeof(response
));
1153 session
= session_get_by_id(session_id
);
1155 DBG("Relay session %" PRIu64
" not found", session_id
);
1156 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR
);
1160 if (!viewer_session_is_attached(conn
->viewer_session
, session
)) {
1161 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR
);
1166 * For any new stream, create it with LTTNG_VIEWER_SEEK_BEGINNING since
1167 * that at this point the client is already attached to the session.Aany
1168 * initial stream will have been created with the seek type at attach
1169 * time (for now most readers use the LTTNG_VIEWER_SEEK_LAST on attach).
1170 * Otherwise any event happening in a new stream between the attach and
1171 * a call to viewer_get_new_streams will be "lost" (never received) from
1172 * the viewer's point of view.
1174 pthread_mutex_lock(&session
->lock
);
1176 * If a session rotation is ongoing, do not attempt to open any
1177 * stream, because the chunk can be in an intermediate state
1178 * due to directory renaming.
1180 if (session_has_ongoing_rotation(session
)) {
1181 DBG("Relay session %" PRIu64
" rotation ongoing", session_id
);
1182 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_NO_NEW
);
1183 goto send_reply_unlock
;
1185 ret
= make_viewer_streams(session
,
1186 conn
->viewer_session
,
1187 LTTNG_VIEWER_SEEK_BEGINNING
,
1194 * This is caused by an internal error; propagate the negative
1195 * 'ret' to close the connection.
1197 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR
);
1198 goto send_reply_unlock
;
1201 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_OK
);
1203 /* Only send back the newly created streams with the unsent ones. */
1204 nb_streams
= nb_created
+ nb_unsent
;
1205 response
.streams_count
= htobe32(nb_streams
);
1208 * If the session is closed, HUP when there are no more streams
1211 if (closed
&& nb_total
== 0) {
1213 response
.streams_count
= 0;
1214 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_HUP
);
1215 goto send_reply_unlock
;
1218 pthread_mutex_unlock(&session
->lock
);
1221 health_code_update();
1222 ret
= send_response(conn
->sock
, &response
, sizeof(response
));
1224 goto end_put_session
;
1226 health_code_update();
1229 * Unknown or empty session, just return gracefully, the viewer
1230 * knows what is happening.
1232 if (!send_streams
|| !nb_streams
) {
1234 goto end_put_session
;
1238 * Send stream and *DON'T* ignore the sent flag so every viewer
1239 * streams that were not sent from that point will be sent to
1242 ret
= send_viewer_streams(conn
->sock
, session_id
, 0);
1244 goto end_put_session
;
1249 session_put(session
);
1256 * Send the viewer the list of current sessions.
1258 static int viewer_attach_session(struct relay_connection
*conn
)
1260 int send_streams
= 0;
1262 uint32_t nb_streams
= 0;
1263 enum lttng_viewer_seek seek_type
;
1264 struct lttng_viewer_attach_session_request request
;
1265 struct lttng_viewer_attach_session_response response
;
1266 struct relay_session
*session
= nullptr;
1267 enum lttng_viewer_attach_return_code viewer_attach_status
;
1268 bool closed
= false;
1269 uint64_t session_id
;
1273 health_code_update();
1275 /* Receive the request from the connected client. */
1276 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
1281 session_id
= be64toh(request
.session_id
);
1283 health_code_update();
1285 memset(&response
, 0, sizeof(response
));
1287 if (!conn
->viewer_session
) {
1288 viewer_attach_status
= LTTNG_VIEWER_ATTACH_NO_SESSION
;
1289 DBG("Client trying to attach before creating a live viewer session, returning status=%s",
1290 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1294 session
= session_get_by_id(session_id
);
1296 viewer_attach_status
= LTTNG_VIEWER_ATTACH_UNK
;
1297 DBG("Relay session %" PRIu64
" not found, returning status=%s",
1299 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1302 DBG("Attach relay session ID %" PRIu64
" received", session_id
);
1304 pthread_mutex_lock(&session
->lock
);
1305 if (session
->live_timer
== 0) {
1306 viewer_attach_status
= LTTNG_VIEWER_ATTACH_NOT_LIVE
;
1307 DBG("Relay session ID %" PRIu64
" is not a live session, returning status=%s",
1309 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1314 viewer_attach_status
= viewer_session_attach(conn
->viewer_session
, session
);
1315 if (viewer_attach_status
!= LTTNG_VIEWER_ATTACH_OK
) {
1316 DBG("Error attaching to relay session %" PRIu64
", returning status=%s",
1318 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1322 switch (be32toh(request
.seek
)) {
1323 case LTTNG_VIEWER_SEEK_BEGINNING
:
1324 case LTTNG_VIEWER_SEEK_LAST
:
1325 viewer_attach_status
= LTTNG_VIEWER_ATTACH_OK
;
1326 seek_type
= (lttng_viewer_seek
) be32toh(request
.seek
);
1329 ERR("Wrong seek parameter for relay session %" PRIu64
", returning status=%s",
1331 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1332 viewer_attach_status
= LTTNG_VIEWER_ATTACH_SEEK_ERR
;
1338 * If a session rotation is ongoing, do not attempt to open any
1339 * stream, because the chunk can be in an intermediate state
1340 * due to directory renaming.
1342 if (session_has_ongoing_rotation(session
)) {
1343 DBG("Relay session %" PRIu64
" rotation ongoing", session_id
);
1348 ret
= make_viewer_streams(
1349 session
, conn
->viewer_session
, seek_type
, &nb_streams
, nullptr, nullptr, &closed
);
1351 goto end_put_session
;
1353 pthread_mutex_unlock(&session
->lock
);
1354 session_put(session
);
1357 response
.streams_count
= htobe32(nb_streams
);
1359 * If the session is closed when the viewer is attaching, it
1360 * means some of the streams may have been concurrently removed,
1361 * so we don't allow the viewer to attach, even if there are
1362 * streams available.
1366 response
.streams_count
= 0;
1367 viewer_attach_status
= LTTNG_VIEWER_ATTACH_UNK
;
1368 ERR("Session %" PRIu64
" is closed, returning status=%s",
1370 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1375 health_code_update();
1377 response
.status
= htobe32((uint32_t) viewer_attach_status
);
1379 ret
= send_response(conn
->sock
, &response
, sizeof(response
));
1381 goto end_put_session
;
1383 health_code_update();
1386 * Unknown or empty session, just return gracefully, the viewer
1387 * knows what is happening.
1389 if (!send_streams
|| !nb_streams
) {
1391 goto end_put_session
;
1394 /* Send stream and ignore the sent flag. */
1395 ret
= send_viewer_streams(conn
->sock
, session_id
, 1);
1397 goto end_put_session
;
1402 pthread_mutex_unlock(&session
->lock
);
1403 session_put(session
);
1410 * Open the index file if needed for the given vstream.
1412 * If an index file is successfully opened, the vstream will set it as its
1413 * current index file.
1415 * Return 0 on success, a negative value on error (-ENOENT if not ready yet).
1417 * Called with rstream lock held.
1419 static int try_open_index(struct relay_viewer_stream
*vstream
, struct relay_stream
*rstream
)
1422 const uint32_t connection_major
= rstream
->trace
->session
->major
;
1423 const uint32_t connection_minor
= rstream
->trace
->session
->minor
;
1424 enum lttng_trace_chunk_status chunk_status
;
1426 if (vstream
->index_file
) {
1431 * First time, we open the index file and at least one index is ready.
1433 if (rstream
->index_received_seqcount
== 0 || !vstream
->stream_file
.trace_chunk
) {
1438 chunk_status
= lttng_index_file_create_from_trace_chunk_read_only(
1439 vstream
->stream_file
.trace_chunk
,
1441 rstream
->channel_name
,
1442 rstream
->tracefile_size
,
1443 vstream
->current_tracefile_id
,
1444 lttng_to_index_major(connection_major
, connection_minor
),
1445 lttng_to_index_minor(connection_major
, connection_minor
),
1447 &vstream
->index_file
);
1448 if (chunk_status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
1449 if (chunk_status
== LTTNG_TRACE_CHUNK_STATUS_NO_FILE
) {
1461 * Check the status of the index for the given stream. This function
1462 * updates the index structure if needed and can put (close) the vstream
1463 * in the HUP situation.
1465 * Return 0 means that we can proceed with the index. A value of 1 means
1466 * that the index has been updated and is ready to be sent to the
1467 * client. A negative value indicates an error that can't be handled.
1469 * Called with rstream lock held.
1471 static int check_index_status(struct relay_viewer_stream
*vstream
,
1472 struct relay_stream
*rstream
,
1473 struct ctf_trace
*trace
,
1474 struct lttng_viewer_index
*index
)
1478 DBG("Check index status: index_received_seqcount %" PRIu64
" "
1479 "index_sent_seqcount %" PRIu64
" "
1480 "for stream %" PRIu64
,
1481 rstream
->index_received_seqcount
,
1482 vstream
->index_sent_seqcount
,
1483 vstream
->stream
->stream_handle
);
1484 if ((trace
->session
->connection_closed
|| rstream
->closed
) &&
1485 rstream
->index_received_seqcount
== vstream
->index_sent_seqcount
) {
1487 * Last index sent and session connection or relay
1488 * stream are closed.
1490 index
->status
= LTTNG_VIEWER_INDEX_HUP
;
1491 DBG("Check index status: Connection or stream are closed, stream %" PRIu64
1492 ",connection-closed=%d, relay-stream-closed=%d, returning status=%s",
1493 vstream
->stream
->stream_handle
,
1494 trace
->session
->connection_closed
,
1496 lttng_viewer_next_index_return_code_str(
1497 (enum lttng_viewer_next_index_return_code
) index
->status
));
1499 } else if (rstream
->beacon_ts_end
!= -1ULL &&
1500 (rstream
->index_received_seqcount
== 0 ||
1501 (vstream
->index_sent_seqcount
!= 0 &&
1502 rstream
->index_received_seqcount
<= vstream
->index_sent_seqcount
))) {
1504 * We've received a synchronization beacon and the last index
1505 * available has been sent, the index for now is inactive.
1507 * In this case, we have received a beacon which allows us to
1508 * inform the client of a time interval during which we can
1509 * guarantee that there are no events to read (and never will
1512 * The sent seqcount can grow higher than receive seqcount on
1513 * clear because the rotation performed by clear will push
1514 * the index_sent_seqcount ahead (see
1515 * viewer_stream_sync_tracefile_array_tail) and skip over
1516 * packet sequence numbers.
1518 index
->status
= LTTNG_VIEWER_INDEX_INACTIVE
;
1519 index
->timestamp_end
= htobe64(rstream
->beacon_ts_end
);
1520 index
->stream_id
= htobe64(rstream
->ctf_stream_id
);
1521 DBG("Check index status: inactive with beacon, for stream %" PRIu64
1522 ", returning status=%s",
1523 vstream
->stream
->stream_handle
,
1524 lttng_viewer_next_index_return_code_str(
1525 (enum lttng_viewer_next_index_return_code
) index
->status
));
1527 } else if (rstream
->index_received_seqcount
== 0 ||
1528 (vstream
->index_sent_seqcount
!= 0 &&
1529 rstream
->index_received_seqcount
<= vstream
->index_sent_seqcount
)) {
1531 * This checks whether received <= sent seqcount. In
1532 * this case, we have not received a beacon. Therefore,
1533 * we can only ask the client to retry later.
1535 * The sent seqcount can grow higher than receive seqcount on
1536 * clear because the rotation performed by clear will push
1537 * the index_sent_seqcount ahead (see
1538 * viewer_stream_sync_tracefile_array_tail) and skip over
1539 * packet sequence numbers.
1541 index
->status
= LTTNG_VIEWER_INDEX_RETRY
;
1542 DBG("Check index status:"
1543 "did not received beacon for stream %" PRIu64
", returning status=%s",
1544 vstream
->stream
->stream_handle
,
1545 lttng_viewer_next_index_return_code_str(
1546 (enum lttng_viewer_next_index_return_code
) index
->status
));
1548 } else if (!tracefile_array_seq_in_file(rstream
->tfa
,
1549 vstream
->current_tracefile_id
,
1550 vstream
->index_sent_seqcount
)) {
1552 * The next index we want to send cannot be read either
1553 * because we need to perform a rotation, or due to
1554 * the producer having overwritten its trace file.
1556 DBG("Viewer stream %" PRIu64
" rotation", vstream
->stream
->stream_handle
);
1557 ret
= viewer_stream_rotate(vstream
);
1559 /* EOF across entire stream. */
1560 index
->status
= LTTNG_VIEWER_INDEX_HUP
;
1561 DBG("Check index status:"
1562 "reached end of file for stream %" PRIu64
", returning status=%s",
1563 vstream
->stream
->stream_handle
,
1564 lttng_viewer_next_index_return_code_str(
1565 (enum lttng_viewer_next_index_return_code
) index
->status
));
1569 * If we have been pushed due to overwrite, it
1570 * necessarily means there is data that can be read in
1571 * the stream. If we rotated because we reached the end
1572 * of a tracefile, it means the following tracefile
1573 * needs to contain at least one index, else we would
1574 * have already returned LTTNG_VIEWER_INDEX_RETRY to the
1575 * viewer. The updated index_sent_seqcount needs to
1576 * point to a readable index entry now.
1578 * In the case where we "rotate" on a single file, we
1579 * can end up in a case where the requested index is
1580 * still unavailable.
1582 if (rstream
->tracefile_count
== 1 &&
1583 !tracefile_array_seq_in_file(rstream
->tfa
,
1584 vstream
->current_tracefile_id
,
1585 vstream
->index_sent_seqcount
)) {
1586 index
->status
= LTTNG_VIEWER_INDEX_RETRY
;
1587 DBG("Check index status:"
1588 "tracefile array sequence number %" PRIu64
1589 " not in file for stream %" PRIu64
", returning status=%s",
1590 vstream
->index_sent_seqcount
,
1591 vstream
->stream
->stream_handle
,
1592 lttng_viewer_next_index_return_code_str(
1593 (enum lttng_viewer_next_index_return_code
) index
->status
));
1596 LTTNG_ASSERT(tracefile_array_seq_in_file(
1597 rstream
->tfa
, vstream
->current_tracefile_id
, vstream
->index_sent_seqcount
));
1599 /* ret == 0 means successful so we continue. */
1604 viewer_stream_put(vstream
);
1609 static void viewer_stream_rotate_to_trace_chunk(struct relay_viewer_stream
*vstream
,
1610 struct lttng_trace_chunk
*new_trace_chunk
)
1612 lttng_trace_chunk_put(vstream
->stream_file
.trace_chunk
);
1614 if (new_trace_chunk
) {
1615 const bool acquired_reference
= lttng_trace_chunk_get(new_trace_chunk
);
1617 LTTNG_ASSERT(acquired_reference
);
1620 vstream
->stream_file
.trace_chunk
= new_trace_chunk
;
1621 viewer_stream_sync_tracefile_array_tail(vstream
);
1622 viewer_stream_close_files(vstream
);
1626 * Send the next index for a stream.
1628 * Return 0 on success or else a negative value.
1630 static int viewer_get_next_index(struct relay_connection
*conn
)
1633 struct lttng_viewer_get_next_index request_index
;
1634 struct lttng_viewer_index viewer_index
;
1635 struct ctf_packet_index packet_index
;
1636 struct relay_viewer_stream
*vstream
= nullptr;
1637 struct relay_stream
*rstream
= nullptr;
1638 struct ctf_trace
*ctf_trace
= nullptr;
1639 struct relay_viewer_stream
*metadata_viewer_stream
= nullptr;
1640 bool viewer_stream_and_session_in_same_chunk
, viewer_stream_one_rotation_behind
;
1641 uint64_t stream_file_chunk_id
= -1ULL, viewer_session_chunk_id
= -1ULL;
1642 enum lttng_trace_chunk_status status
;
1646 memset(&viewer_index
, 0, sizeof(viewer_index
));
1647 health_code_update();
1649 ret
= recv_request(conn
->sock
, &request_index
, sizeof(request_index
));
1653 health_code_update();
1655 vstream
= viewer_stream_get_by_id(be64toh(request_index
.stream_id
));
1657 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1658 DBG("Client requested index of unknown stream id %" PRIu64
", returning status=%s",
1659 (uint64_t) be64toh(request_index
.stream_id
),
1660 lttng_viewer_next_index_return_code_str(
1661 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1665 /* Use back. ref. Protected by refcounts. */
1666 rstream
= vstream
->stream
;
1667 ctf_trace
= rstream
->trace
;
1669 /* metadata_viewer_stream may be NULL. */
1670 metadata_viewer_stream
= ctf_trace_get_viewer_metadata_stream(ctf_trace
);
1673 * Hold the session lock to protect against concurrent changes
1674 * to the chunk files (e.g. rename done by clear), which are
1675 * protected by the session ongoing rotation state. Those are
1676 * synchronized with the session lock.
1678 pthread_mutex_lock(&rstream
->trace
->session
->lock
);
1679 pthread_mutex_lock(&rstream
->lock
);
1682 * The viewer should not ask for index on metadata stream.
1684 if (rstream
->is_metadata
) {
1685 viewer_index
.status
= LTTNG_VIEWER_INDEX_HUP
;
1686 DBG("Client requested index of a metadata stream id %" PRIu64
1687 ", returning status=%s",
1688 (uint64_t) be64toh(request_index
.stream_id
),
1689 lttng_viewer_next_index_return_code_str(
1690 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1694 if (rstream
->ongoing_rotation
.is_set
) {
1695 /* Rotation is ongoing, try again later. */
1696 viewer_index
.status
= LTTNG_VIEWER_INDEX_RETRY
;
1697 DBG("Client requested index for stream id %" PRIu64
1698 " while a stream rotation is ongoing, returning status=%s",
1699 (uint64_t) be64toh(request_index
.stream_id
),
1700 lttng_viewer_next_index_return_code_str(
1701 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1705 if (session_has_ongoing_rotation(rstream
->trace
->session
)) {
1706 /* Rotation is ongoing, try again later. */
1707 viewer_index
.status
= LTTNG_VIEWER_INDEX_RETRY
;
1708 DBG("Client requested index for stream id %" PRIu64
1709 " while a session rotation is ongoing, returning status=%s",
1710 (uint64_t) be64toh(request_index
.stream_id
),
1711 lttng_viewer_next_index_return_code_str(
1712 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1717 * Transition the viewer session into the newest trace chunk available.
1719 if (!lttng_trace_chunk_ids_equal(conn
->viewer_session
->current_trace_chunk
,
1720 rstream
->trace_chunk
)) {
1721 DBG("Relay stream and viewer chunk ids differ");
1723 ret
= viewer_session_set_trace_chunk_copy(conn
->viewer_session
,
1724 rstream
->trace_chunk
);
1726 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1727 ERR("Error copying trace chunk for stream id %" PRIu64
1728 ", returning status=%s",
1729 (uint64_t) be64toh(request_index
.stream_id
),
1730 lttng_viewer_next_index_return_code_str(
1731 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1737 * Transition the viewer stream into the latest trace chunk available.
1739 * Note that the stream must _not_ rotate in one precise condition:
1740 * the relay stream has rotated to a NULL trace chunk and the viewer
1741 * stream is consuming the trace chunk that was active just before
1742 * that rotation to NULL.
1744 * This allows clients to consume all the packets of a trace chunk
1745 * after a session's destruction.
1747 if (vstream
->stream_file
.trace_chunk
) {
1748 status
= lttng_trace_chunk_get_id(vstream
->stream_file
.trace_chunk
,
1749 &stream_file_chunk_id
);
1750 LTTNG_ASSERT(status
== LTTNG_TRACE_CHUNK_STATUS_OK
);
1752 if (conn
->viewer_session
->current_trace_chunk
) {
1753 status
= lttng_trace_chunk_get_id(conn
->viewer_session
->current_trace_chunk
,
1754 &viewer_session_chunk_id
);
1755 LTTNG_ASSERT(status
== LTTNG_TRACE_CHUNK_STATUS_OK
);
1758 viewer_stream_and_session_in_same_chunk
= lttng_trace_chunk_ids_equal(
1759 conn
->viewer_session
->current_trace_chunk
, vstream
->stream_file
.trace_chunk
);
1760 viewer_stream_one_rotation_behind
= rstream
->completed_rotation_count
==
1761 vstream
->last_seen_rotation_count
+ 1;
1763 if (viewer_stream_and_session_in_same_chunk
) {
1764 DBG("Transition to latest chunk check (%s -> %s): Same chunk, no need to rotate",
1765 vstream
->stream_file
.trace_chunk
?
1766 std::to_string(stream_file_chunk_id
).c_str() :
1768 conn
->viewer_session
->current_trace_chunk
?
1769 std::to_string(viewer_session_chunk_id
).c_str() :
1771 } else if (viewer_stream_one_rotation_behind
&& !rstream
->trace_chunk
) {
1772 DBG("Transition to latest chunk check (%s -> %s): One chunk behind relay stream which is being destroyed, no need to rotate",
1773 vstream
->stream_file
.trace_chunk
?
1774 std::to_string(stream_file_chunk_id
).c_str() :
1776 conn
->viewer_session
->current_trace_chunk
?
1777 std::to_string(viewer_session_chunk_id
).c_str() :
1780 DBG("Transition to latest chunk check (%s -> %s): Viewer stream chunk ID and viewer session chunk ID differ, rotating viewer stream",
1781 vstream
->stream_file
.trace_chunk
?
1782 std::to_string(stream_file_chunk_id
).c_str() :
1784 conn
->viewer_session
->current_trace_chunk
?
1785 std::to_string(viewer_session_chunk_id
).c_str() :
1788 viewer_stream_rotate_to_trace_chunk(vstream
,
1789 conn
->viewer_session
->current_trace_chunk
);
1790 vstream
->last_seen_rotation_count
= rstream
->completed_rotation_count
;
1793 ret
= check_index_status(vstream
, rstream
, ctf_trace
, &viewer_index
);
1796 } else if (ret
== 1) {
1798 * We have no index to send and check_index_status has populated
1799 * viewer_index's status.
1803 /* At this point, ret is 0 thus we will be able to read the index. */
1806 /* Try to open an index if one is needed for that stream. */
1807 ret
= try_open_index(vstream
, rstream
);
1808 if (ret
== -ENOENT
) {
1809 if (rstream
->closed
) {
1810 viewer_index
.status
= LTTNG_VIEWER_INDEX_HUP
;
1811 DBG("Cannot open index for stream id %" PRIu64
1812 "stream is closed, returning status=%s",
1813 (uint64_t) be64toh(request_index
.stream_id
),
1814 lttng_viewer_next_index_return_code_str(
1815 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1818 viewer_index
.status
= LTTNG_VIEWER_INDEX_RETRY
;
1819 DBG("Cannot open index for stream id %" PRIu64
", returning status=%s",
1820 (uint64_t) be64toh(request_index
.stream_id
),
1821 lttng_viewer_next_index_return_code_str(
1822 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1827 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1828 ERR("Error opening index for stream id %" PRIu64
", returning status=%s",
1829 (uint64_t) be64toh(request_index
.stream_id
),
1830 lttng_viewer_next_index_return_code_str(
1831 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1836 * vstream->stream_fd may be NULL if it has been closed by
1837 * tracefile rotation, or if we are at the beginning of the
1838 * stream. We open the data stream file here to protect against
1839 * overwrite caused by tracefile rotation (in association with
1840 * unlink performed before overwrite).
1842 if (!vstream
->stream_file
.handle
) {
1843 char file_path
[LTTNG_PATH_MAX
];
1844 struct fs_handle
*fs_handle
;
1846 ret
= utils_stream_file_path(rstream
->path_name
,
1847 rstream
->channel_name
,
1848 rstream
->tracefile_size
,
1849 vstream
->current_tracefile_id
,
1858 * It is possible the the file we are trying to open is
1859 * missing if the stream has been closed (application exits with
1860 * per-pid buffers) and a clear command has been performed.
1862 status
= lttng_trace_chunk_open_fs_handle(
1863 vstream
->stream_file
.trace_chunk
, file_path
, O_RDONLY
, 0, &fs_handle
, true);
1864 if (status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
1865 if (status
== LTTNG_TRACE_CHUNK_STATUS_NO_FILE
&& rstream
->closed
) {
1866 viewer_index
.status
= LTTNG_VIEWER_INDEX_HUP
;
1867 DBG("Cannot find trace chunk file and stream is closed for stream id %" PRIu64
1868 ", returning status=%s",
1869 (uint64_t) be64toh(request_index
.stream_id
),
1870 lttng_viewer_next_index_return_code_str(
1871 (enum lttng_viewer_next_index_return_code
)
1872 viewer_index
.status
));
1875 PERROR("Failed to open trace file for viewer stream");
1878 vstream
->stream_file
.handle
= fs_handle
;
1881 ret
= check_new_streams(conn
);
1883 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1884 ERR("Error checking for new streams before sending new index to stream id %" PRIu64
1885 ", returning status=%s",
1886 (uint64_t) be64toh(request_index
.stream_id
),
1887 lttng_viewer_next_index_return_code_str(
1888 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1890 } else if (ret
== 1) {
1891 viewer_index
.flags
|= LTTNG_VIEWER_FLAG_NEW_STREAM
;
1894 ret
= lttng_index_file_read(vstream
->index_file
, &packet_index
);
1896 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1897 ERR("Relay error reading index file for stream id %" PRIu64
", returning status=%s",
1898 (uint64_t) be64toh(request_index
.stream_id
),
1899 lttng_viewer_next_index_return_code_str(
1900 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1903 viewer_index
.status
= LTTNG_VIEWER_INDEX_OK
;
1904 DBG("Read index file for stream id %" PRIu64
", returning status=%s",
1905 (uint64_t) be64toh(request_index
.stream_id
),
1906 lttng_viewer_next_index_return_code_str(
1907 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1908 vstream
->index_sent_seqcount
++;
1912 * Indexes are stored in big endian, no need to switch before sending.
1914 DBG("Sending viewer index for stream %" PRIu64
" offset %" PRIu64
,
1915 rstream
->stream_handle
,
1916 (uint64_t) be64toh(packet_index
.offset
));
1917 viewer_index
.offset
= packet_index
.offset
;
1918 viewer_index
.packet_size
= packet_index
.packet_size
;
1919 viewer_index
.content_size
= packet_index
.content_size
;
1920 viewer_index
.timestamp_begin
= packet_index
.timestamp_begin
;
1921 viewer_index
.timestamp_end
= packet_index
.timestamp_end
;
1922 viewer_index
.events_discarded
= packet_index
.events_discarded
;
1923 viewer_index
.stream_id
= packet_index
.stream_id
;
1927 pthread_mutex_unlock(&rstream
->lock
);
1928 pthread_mutex_unlock(&rstream
->trace
->session
->lock
);
1931 if (metadata_viewer_stream
) {
1932 pthread_mutex_lock(&metadata_viewer_stream
->stream
->lock
);
1933 DBG("get next index metadata check: recv %" PRIu64
" sent %" PRIu64
,
1934 metadata_viewer_stream
->stream
->metadata_received
,
1935 metadata_viewer_stream
->metadata_sent
);
1936 if (!metadata_viewer_stream
->stream
->metadata_received
||
1937 metadata_viewer_stream
->stream
->metadata_received
>
1938 metadata_viewer_stream
->metadata_sent
) {
1939 viewer_index
.flags
|= LTTNG_VIEWER_FLAG_NEW_METADATA
;
1941 pthread_mutex_unlock(&metadata_viewer_stream
->stream
->lock
);
1944 viewer_index
.flags
= htobe32(viewer_index
.flags
);
1945 viewer_index
.status
= htobe32(viewer_index
.status
);
1946 health_code_update();
1948 ret
= send_response(conn
->sock
, &viewer_index
, sizeof(viewer_index
));
1952 health_code_update();
1955 DBG("Index %" PRIu64
" for stream %" PRIu64
" sent",
1956 vstream
->index_sent_seqcount
,
1957 vstream
->stream
->stream_handle
);
1960 if (metadata_viewer_stream
) {
1961 viewer_stream_put(metadata_viewer_stream
);
1964 viewer_stream_put(vstream
);
1969 pthread_mutex_unlock(&rstream
->lock
);
1970 pthread_mutex_unlock(&rstream
->trace
->session
->lock
);
1971 if (metadata_viewer_stream
) {
1972 viewer_stream_put(metadata_viewer_stream
);
1974 viewer_stream_put(vstream
);
1979 * Send the next index for a stream
1981 * Return 0 on success or else a negative value.
1983 static int viewer_get_packet(struct relay_connection
*conn
)
1987 char *reply
= nullptr;
1988 struct lttng_viewer_get_packet get_packet_info
;
1989 struct lttng_viewer_trace_packet reply_header
;
1990 struct relay_viewer_stream
*vstream
= nullptr;
1991 uint32_t reply_size
= sizeof(reply_header
);
1992 uint32_t packet_data_len
= 0;
1995 enum lttng_viewer_get_packet_return_code get_packet_status
;
1997 health_code_update();
1999 ret
= recv_request(conn
->sock
, &get_packet_info
, sizeof(get_packet_info
));
2003 health_code_update();
2005 /* From this point on, the error label can be reached. */
2006 memset(&reply_header
, 0, sizeof(reply_header
));
2007 stream_id
= (uint64_t) be64toh(get_packet_info
.stream_id
);
2009 vstream
= viewer_stream_get_by_id(stream_id
);
2011 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2012 DBG("Client requested packet of unknown stream id %" PRIu64
", returning status=%s",
2014 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2015 goto send_reply_nolock
;
2017 packet_data_len
= be32toh(get_packet_info
.len
);
2018 reply_size
+= packet_data_len
;
2021 reply
= zmalloc
<char>(reply_size
);
2023 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2024 PERROR("Falled to allocate reply, returning status=%s",
2025 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2029 pthread_mutex_lock(&vstream
->stream
->lock
);
2030 lseek_ret
= fs_handle_seek(
2031 vstream
->stream_file
.handle
, be64toh(get_packet_info
.offset
), SEEK_SET
);
2032 if (lseek_ret
< 0) {
2033 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2034 PERROR("Failed to seek file system handle of viewer stream %" PRIu64
2035 " to offset %" PRIu64
", returning status=%s",
2037 (uint64_t) be64toh(get_packet_info
.offset
),
2038 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2041 read_len
= fs_handle_read(
2042 vstream
->stream_file
.handle
, reply
+ sizeof(reply_header
), packet_data_len
);
2043 if (read_len
< packet_data_len
) {
2044 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2045 PERROR("Failed to read from file system handle of viewer stream id %" PRIu64
2046 ", offset: %" PRIu64
", returning status=%s",
2048 (uint64_t) be64toh(get_packet_info
.offset
),
2049 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2053 get_packet_status
= LTTNG_VIEWER_GET_PACKET_OK
;
2054 reply_header
.len
= htobe32(packet_data_len
);
2058 /* No payload to send on error. */
2059 reply_size
= sizeof(reply_header
);
2063 pthread_mutex_unlock(&vstream
->stream
->lock
);
2067 health_code_update();
2069 reply_header
.status
= htobe32(get_packet_status
);
2071 memcpy(reply
, &reply_header
, sizeof(reply_header
));
2072 ret
= send_response(conn
->sock
, reply
, reply_size
);
2074 /* No reply to send. */
2075 ret
= send_response(conn
->sock
, &reply_header
, reply_size
);
2078 health_code_update();
2080 PERROR("sendmsg of packet data failed");
2084 DBG("Sent %u bytes for stream %" PRIu64
, reply_size
, stream_id
);
2090 viewer_stream_put(vstream
);
2096 * Send the session's metadata
2098 * Return 0 on success else a negative value.
2100 static int viewer_get_metadata(struct relay_connection
*conn
)
2106 char *data
= nullptr;
2107 struct lttng_viewer_get_metadata request
;
2108 struct lttng_viewer_metadata_packet reply
;
2109 struct relay_viewer_stream
*vstream
= nullptr;
2113 health_code_update();
2115 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
2119 health_code_update();
2121 memset(&reply
, 0, sizeof(reply
));
2123 vstream
= viewer_stream_get_by_id(be64toh(request
.stream_id
));
2126 * The metadata stream can be closed by a CLOSE command
2127 * just before we attach. It can also be closed by
2128 * per-pid tracing during tracing. Therefore, it is
2129 * possible that we cannot find this viewer stream.
2130 * Reply back to the client with an error if we cannot
2133 DBG("Client requested metadata of unknown stream id %" PRIu64
,
2134 (uint64_t) be64toh(request
.stream_id
));
2135 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2138 pthread_mutex_lock(&vstream
->stream
->lock
);
2139 if (!vstream
->stream
->is_metadata
) {
2140 ERR("Invalid metadata stream");
2144 if (vstream
->metadata_sent
>= vstream
->stream
->metadata_received
) {
2146 * The live viewers expect to receive a NO_NEW_METADATA
2147 * status before a stream disappears, otherwise they abort the
2148 * entire live connection when receiving an error status.
2150 * Clear feature resets the metadata_sent to 0 until the
2151 * same metadata is received again.
2153 reply
.status
= htobe32(LTTNG_VIEWER_NO_NEW_METADATA
);
2155 * The live viewer considers a closed 0 byte metadata stream as
2158 if (vstream
->metadata_sent
> 0) {
2159 if (vstream
->stream
->closed
&& vstream
->stream
->no_new_metadata_notified
) {
2161 * Release ownership for the viewer metadata
2162 * stream. Note that this reference is the
2163 * viewer's reference. The vstream still exists
2164 * until the end of the function as
2165 * viewer_stream_get_by_id() took a reference.
2167 viewer_stream_put(vstream
);
2170 vstream
->stream
->no_new_metadata_notified
= true;
2175 if (vstream
->stream
->trace_chunk
&&
2176 !lttng_trace_chunk_ids_equal(conn
->viewer_session
->current_trace_chunk
,
2177 vstream
->stream
->trace_chunk
)) {
2178 /* A rotation has occurred on the relay stream. */
2179 DBG("Metadata relay stream and viewer chunk ids differ");
2181 ret
= viewer_session_set_trace_chunk_copy(conn
->viewer_session
,
2182 vstream
->stream
->trace_chunk
);
2184 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2189 if (conn
->viewer_session
->current_trace_chunk
&&
2190 !lttng_trace_chunk_ids_equal(conn
->viewer_session
->current_trace_chunk
,
2191 vstream
->stream_file
.trace_chunk
)) {
2192 bool acquired_reference
;
2194 DBG("Viewer session and viewer stream chunk differ: "
2195 "vsession chunk %p vstream chunk %p",
2196 conn
->viewer_session
->current_trace_chunk
,
2197 vstream
->stream_file
.trace_chunk
);
2198 lttng_trace_chunk_put(vstream
->stream_file
.trace_chunk
);
2199 acquired_reference
=
2200 lttng_trace_chunk_get(conn
->viewer_session
->current_trace_chunk
);
2201 LTTNG_ASSERT(acquired_reference
);
2202 vstream
->stream_file
.trace_chunk
= conn
->viewer_session
->current_trace_chunk
;
2203 viewer_stream_close_files(vstream
);
2206 len
= vstream
->stream
->metadata_received
- vstream
->metadata_sent
;
2208 if (!vstream
->stream_file
.trace_chunk
) {
2209 reply
.status
= htobe32(LTTNG_VIEWER_NO_NEW_METADATA
);
2212 } else if (vstream
->stream_file
.trace_chunk
&& !vstream
->stream_file
.handle
&& len
> 0) {
2214 * Either this is the first time the metadata file is read, or a
2215 * rotation of the corresponding relay stream has occurred.
2217 struct fs_handle
*fs_handle
;
2218 char file_path
[LTTNG_PATH_MAX
];
2219 enum lttng_trace_chunk_status status
;
2220 struct relay_stream
*rstream
= vstream
->stream
;
2222 ret
= utils_stream_file_path(rstream
->path_name
,
2223 rstream
->channel_name
,
2224 rstream
->tracefile_size
,
2225 vstream
->current_tracefile_id
,
2234 * It is possible the the metadata file we are trying to open is
2235 * missing if the stream has been closed (application exits with
2236 * per-pid buffers) and a clear command has been performed.
2238 status
= lttng_trace_chunk_open_fs_handle(
2239 vstream
->stream_file
.trace_chunk
, file_path
, O_RDONLY
, 0, &fs_handle
, true);
2240 if (status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
2241 if (status
== LTTNG_TRACE_CHUNK_STATUS_NO_FILE
) {
2242 reply
.status
= htobe32(LTTNG_VIEWER_NO_NEW_METADATA
);
2244 if (vstream
->stream
->closed
) {
2245 viewer_stream_put(vstream
);
2249 PERROR("Failed to open metadata file for viewer stream");
2252 vstream
->stream_file
.handle
= fs_handle
;
2254 if (vstream
->metadata_sent
!= 0) {
2256 * The client does not expect to receive any metadata
2257 * it has received and metadata files in successive
2258 * chunks must be a strict superset of one another.
2260 * Skip the first `metadata_sent` bytes to ensure
2261 * they are not sent a second time to the client.
2263 * Baring a block layer error or an internal error,
2264 * this seek should not fail as
2265 * `vstream->stream->metadata_received` is reset when
2266 * a relay stream is rotated. If this is reached, it is
2267 * safe to assume that
2268 * `metadata_received` > `metadata_sent`.
2270 const off_t seek_ret
=
2271 fs_handle_seek(fs_handle
, vstream
->metadata_sent
, SEEK_SET
);
2274 PERROR("Failed to seek metadata viewer stream file to `sent` position: pos = %" PRId64
,
2275 vstream
->metadata_sent
);
2276 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2282 reply
.len
= htobe64(len
);
2283 data
= zmalloc
<char>(len
);
2285 PERROR("viewer metadata zmalloc");
2289 fd
= fs_handle_get_fd(vstream
->stream_file
.handle
);
2291 ERR("Failed to restore viewer stream file system handle");
2294 read_len
= lttng_read(fd
, data
, len
);
2295 fs_handle_put_fd(vstream
->stream_file
.handle
);
2297 if (read_len
< len
) {
2299 PERROR("Failed to read metadata file");
2303 * A clear has been performed which prevents the relay
2304 * from sending `len` bytes of metadata.
2306 * It is important not to send any metadata if we
2307 * couldn't read all the available metadata in one shot:
2308 * sending partial metadata can cause the client to
2309 * attempt to parse an incomplete (incoherent) metadata
2310 * stream, which would result in an error.
2312 const off_t seek_ret
=
2313 fs_handle_seek(vstream
->stream_file
.handle
, -read_len
, SEEK_CUR
);
2315 DBG("Failed to read metadata: requested = %" PRIu64
", got = %zd",
2321 PERROR("Failed to restore metadata file position after partial read");
2327 vstream
->metadata_sent
+= read_len
;
2328 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_OK
);
2333 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2336 health_code_update();
2338 pthread_mutex_unlock(&vstream
->stream
->lock
);
2340 ret
= send_response(conn
->sock
, &reply
, sizeof(reply
));
2344 health_code_update();
2347 ret
= send_response(conn
->sock
, data
, len
);
2353 DBG("Sent %" PRIu64
" bytes of metadata for stream %" PRIu64
,
2355 (uint64_t) be64toh(request
.stream_id
));
2357 DBG("Metadata sent");
2363 viewer_stream_put(vstream
);
2369 * Create a viewer session.
2371 * Return 0 on success or else a negative value.
2373 static int viewer_create_session(struct relay_connection
*conn
)
2376 struct lttng_viewer_create_session_response resp
;
2378 memset(&resp
, 0, sizeof(resp
));
2379 resp
.status
= htobe32(LTTNG_VIEWER_CREATE_SESSION_OK
);
2380 conn
->viewer_session
= viewer_session_create();
2381 if (!conn
->viewer_session
) {
2382 ERR("Allocation viewer session");
2383 resp
.status
= htobe32(LTTNG_VIEWER_CREATE_SESSION_ERR
);
2388 health_code_update();
2389 ret
= send_response(conn
->sock
, &resp
, sizeof(resp
));
2393 health_code_update();
2401 * Detach a viewer session.
2403 * Return 0 on success or else a negative value.
2405 static int viewer_detach_session(struct relay_connection
*conn
)
2408 struct lttng_viewer_detach_session_response response
;
2409 struct lttng_viewer_detach_session_request request
;
2410 struct relay_session
*session
= nullptr;
2411 uint64_t viewer_session_to_close
;
2415 health_code_update();
2417 /* Receive the request from the connected client. */
2418 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
2422 viewer_session_to_close
= be64toh(request
.session_id
);
2424 if (!conn
->viewer_session
) {
2425 DBG("Client trying to detach before creating a live viewer session");
2426 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR
);
2430 health_code_update();
2432 memset(&response
, 0, sizeof(response
));
2433 DBG("Detaching from session ID %" PRIu64
, viewer_session_to_close
);
2435 session
= session_get_by_id(be64toh(request
.session_id
));
2437 DBG("Relay session %" PRIu64
" not found", (uint64_t) be64toh(request
.session_id
));
2438 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_UNK
);
2442 ret
= viewer_session_is_attached(conn
->viewer_session
, session
);
2444 DBG("Not attached to this session");
2445 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR
);
2446 goto send_reply_put
;
2449 viewer_session_close_one_session(conn
->viewer_session
, session
);
2450 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_OK
);
2451 DBG("Session %" PRIu64
" detached.", viewer_session_to_close
);
2454 session_put(session
);
2457 health_code_update();
2458 ret
= send_response(conn
->sock
, &response
, sizeof(response
));
2462 health_code_update();
2470 * live_relay_unknown_command: send -1 if received unknown command
2472 static void live_relay_unknown_command(struct relay_connection
*conn
)
2474 struct lttcomm_relayd_generic_reply reply
;
2476 memset(&reply
, 0, sizeof(reply
));
2477 reply
.ret_code
= htobe32(LTTNG_ERR_UNK
);
2478 (void) send_response(conn
->sock
, &reply
, sizeof(reply
));
2482 * Process the commands received on the control socket
2484 static int process_control(struct lttng_viewer_cmd
*recv_hdr
, struct relay_connection
*conn
)
2487 lttng_viewer_command cmd
= (lttng_viewer_command
) be32toh(recv_hdr
->cmd
);
2490 * Make sure we've done the version check before any command other then
2491 * a new client connection.
2493 if (cmd
!= LTTNG_VIEWER_CONNECT
&& !conn
->version_check_done
) {
2494 ERR("Viewer on connection %d requested %s command before version check",
2496 lttng_viewer_command_str(cmd
));
2501 DBG("Processing %s viewer command from connection %d",
2502 lttng_viewer_command_str(cmd
),
2506 case LTTNG_VIEWER_CONNECT
:
2507 ret
= viewer_connect(conn
);
2509 case LTTNG_VIEWER_LIST_SESSIONS
:
2510 ret
= viewer_list_sessions(conn
);
2512 case LTTNG_VIEWER_ATTACH_SESSION
:
2513 ret
= viewer_attach_session(conn
);
2515 case LTTNG_VIEWER_GET_NEXT_INDEX
:
2516 ret
= viewer_get_next_index(conn
);
2518 case LTTNG_VIEWER_GET_PACKET
:
2519 ret
= viewer_get_packet(conn
);
2521 case LTTNG_VIEWER_GET_METADATA
:
2522 ret
= viewer_get_metadata(conn
);
2524 case LTTNG_VIEWER_GET_NEW_STREAMS
:
2525 ret
= viewer_get_new_streams(conn
);
2527 case LTTNG_VIEWER_CREATE_SESSION
:
2528 ret
= viewer_create_session(conn
);
2530 case LTTNG_VIEWER_DETACH_SESSION
:
2531 ret
= viewer_detach_session(conn
);
2534 ERR("Received unknown viewer command (%u)", be32toh(recv_hdr
->cmd
));
2535 live_relay_unknown_command(conn
);
2544 static void cleanup_connection_pollfd(struct lttng_poll_event
*events
, int pollfd
)
2548 (void) lttng_poll_del(events
, pollfd
);
2550 ret
= fd_tracker_close_unsuspendable_fd(
2551 the_fd_tracker
, &pollfd
, 1, fd_tracker_util_close_fd
, nullptr);
2553 ERR("Closing pollfd %d", pollfd
);
2558 * This thread does the actual work
2560 static void *thread_worker(void *data
__attribute__((unused
)))
2564 struct lttng_poll_event events
;
2565 struct lttng_ht
*viewer_connections_ht
;
2566 struct lttng_ht_iter iter
;
2567 struct lttng_viewer_cmd recv_hdr
;
2568 struct relay_connection
*destroy_conn
;
2570 DBG("[thread] Live viewer relay worker started");
2572 rcu_register_thread();
2574 health_register(health_relayd
, HEALTH_RELAYD_TYPE_LIVE_WORKER
);
2576 if (testpoint(relayd_thread_live_worker
)) {
2577 goto error_testpoint
;
2580 /* table of connections indexed on socket */
2581 viewer_connections_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
2582 if (!viewer_connections_ht
) {
2583 goto viewer_connections_ht_error
;
2586 ret
= create_named_thread_poll_set(&events
, 2, "Live viewer worker thread epoll");
2588 goto error_poll_create
;
2591 ret
= lttng_poll_add(&events
, live_conn_pipe
[0], LPOLLIN
| LPOLLRDHUP
);
2600 health_code_update();
2602 /* Infinite blocking call, waiting for transmission */
2603 DBG3("Relayd live viewer worker thread polling...");
2604 health_poll_entry();
2605 ret
= lttng_poll_wait(&events
, -1);
2609 * Restart interrupted system call.
2611 if (errno
== EINTR
) {
2620 * Process control. The control connection is prioritised so we don't
2621 * starve it with high throughput tracing data on the data
2624 for (i
= 0; i
< nb_fd
; i
++) {
2625 /* Fetch once the poll data */
2626 const auto revents
= LTTNG_POLL_GETEV(&events
, i
);
2627 const auto pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2629 health_code_update();
2631 /* Activity on thread quit pipe, exiting. */
2632 if (relayd_is_thread_quit_pipe(pollfd
)) {
2633 DBG("Activity on thread quit pipe");
2638 /* Inspect the relay conn pipe for new connection. */
2639 if (pollfd
== live_conn_pipe
[0]) {
2640 if (revents
& LPOLLIN
) {
2641 struct relay_connection
*conn
;
2643 ret
= lttng_read(live_conn_pipe
[0], &conn
, sizeof(conn
));
2647 ret
= lttng_poll_add(
2648 &events
, conn
->sock
->fd
, LPOLLIN
| LPOLLRDHUP
);
2650 ERR("Failed to add new live connection file descriptor to poll set");
2653 connection_ht_add(viewer_connections_ht
, conn
);
2654 DBG("Connection socket %d added to poll", conn
->sock
->fd
);
2655 } else if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2656 ERR("Relay live pipe error");
2659 ERR("Unexpected poll events %u for sock %d",
2665 /* Connection activity. */
2666 struct relay_connection
*conn
;
2668 conn
= connection_get_by_sock(viewer_connections_ht
, pollfd
);
2673 if (revents
& LPOLLIN
) {
2674 ret
= conn
->sock
->ops
->recvmsg(
2675 conn
->sock
, &recv_hdr
, sizeof(recv_hdr
), 0);
2677 /* Connection closed. */
2678 cleanup_connection_pollfd(&events
, pollfd
);
2679 /* Put "create" ownership reference. */
2680 connection_put(conn
);
2681 DBG("Viewer control conn closed with %d", pollfd
);
2683 ret
= process_control(&recv_hdr
, conn
);
2685 /* Clear the session on error. */
2686 cleanup_connection_pollfd(&events
, pollfd
);
2687 /* Put "create" ownership reference. */
2688 connection_put(conn
);
2689 DBG("Viewer connection closed with %d",
2693 } else if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2694 cleanup_connection_pollfd(&events
, pollfd
);
2695 /* Put "create" ownership reference. */
2696 connection_put(conn
);
2698 ERR("Unexpected poll events %u for sock %d",
2701 connection_put(conn
);
2704 /* Put local "get_by_sock" reference. */
2705 connection_put(conn
);
2712 (void) fd_tracker_util_poll_clean(the_fd_tracker
, &events
);
2714 /* Cleanup remaining connection object. */
2716 cds_lfht_for_each_entry (viewer_connections_ht
->ht
, &iter
.iter
, destroy_conn
, sock_n
.node
) {
2717 health_code_update();
2718 connection_put(destroy_conn
);
2722 lttng_ht_destroy(viewer_connections_ht
);
2723 viewer_connections_ht_error
:
2724 /* Close relay conn pipes */
2725 (void) fd_tracker_util_pipe_close(the_fd_tracker
, live_conn_pipe
);
2727 DBG("Viewer worker thread exited with error");
2729 DBG("Viewer worker thread cleanup complete");
2733 ERR("Health error occurred in %s", __func__
);
2735 health_unregister(health_relayd
);
2736 if (lttng_relay_stop_threads()) {
2737 ERR("Error stopping threads");
2739 rcu_unregister_thread();
2744 * Create the relay command pipe to wake thread_manage_apps.
2745 * Closed in cleanup().
2747 static int create_conn_pipe()
2749 return fd_tracker_util_pipe_open_cloexec(
2750 the_fd_tracker
, "Live connection pipe", live_conn_pipe
);
2753 int relayd_live_join()
2755 int ret
, retval
= 0;
2758 ret
= pthread_join(live_listener_thread
, &status
);
2761 PERROR("pthread_join live listener");
2765 ret
= pthread_join(live_worker_thread
, &status
);
2768 PERROR("pthread_join live worker");
2772 ret
= pthread_join(live_dispatcher_thread
, &status
);
2775 PERROR("pthread_join live dispatcher");
2779 cleanup_relayd_live();
2787 int relayd_live_create(struct lttng_uri
*uri
)
2789 int ret
= 0, retval
= 0;
2795 goto exit_init_data
;
2799 /* Check if daemon is UID = 0 */
2800 is_root
= !getuid();
2803 if (live_uri
->port
< 1024) {
2804 ERR("Need to be root to use ports < 1024");
2806 goto exit_init_data
;
2810 /* Setup the thread apps communication pipe. */
2811 if (create_conn_pipe()) {
2813 goto exit_init_data
;
2816 /* Init relay command queue. */
2817 cds_wfcq_init(&viewer_conn_queue
.head
, &viewer_conn_queue
.tail
);
2819 /* Set up max poll set size */
2820 if (lttng_poll_set_max_size()) {
2822 goto exit_init_data
;
2825 /* Setup the dispatcher thread */
2826 ret
= pthread_create(&live_dispatcher_thread
,
2827 default_pthread_attr(),
2832 PERROR("pthread_create viewer dispatcher");
2834 goto exit_dispatcher_thread
;
2837 /* Setup the worker thread */
2838 ret
= pthread_create(&live_worker_thread
, default_pthread_attr(), thread_worker
, nullptr);
2841 PERROR("pthread_create viewer worker");
2843 goto exit_worker_thread
;
2846 /* Setup the listener thread */
2847 ret
= pthread_create(
2848 &live_listener_thread
, default_pthread_attr(), thread_listener
, (void *) nullptr);
2851 PERROR("pthread_create viewer listener");
2853 goto exit_listener_thread
;
2857 * All OK, started all threads.
2862 * Join on the live_listener_thread should anything be added after
2863 * the live_listener thread's creation.
2866 exit_listener_thread
:
2868 ret
= pthread_join(live_worker_thread
, &status
);
2871 PERROR("pthread_join live worker");
2876 ret
= pthread_join(live_dispatcher_thread
, &status
);
2879 PERROR("pthread_join live dispatcher");
2882 exit_dispatcher_thread
:
2885 cleanup_relayd_live();