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/urcu.hpp>
37 #include <common/uri.hpp>
38 #include <common/utils.hpp>
40 #include <lttng/lttng.h>
54 #include <sys/mount.h>
55 #include <sys/resource.h>
56 #include <sys/socket.h>
58 #include <sys/types.h>
61 #include <urcu/futex.h>
62 #include <urcu/rculist.h>
63 #include <urcu/uatomic.h>
65 #define SESSION_BUF_DEFAULT_COUNT 16
67 static struct lttng_uri
*live_uri
;
70 * This pipe is used to inform the worker thread that a command is queued and
71 * ready to be processed.
73 static int live_conn_pipe
[2] = { -1, -1 };
75 /* Shared between threads */
76 static int live_dispatch_thread_exit
;
78 static pthread_t live_listener_thread
;
79 static pthread_t live_dispatcher_thread
;
80 static pthread_t live_worker_thread
;
83 * Relay command queue.
85 * The live_thread_listener and live_thread_dispatcher communicate with this
88 static struct relay_conn_queue viewer_conn_queue
;
90 static uint64_t last_relay_viewer_session_id
;
91 static pthread_mutex_t last_relay_viewer_session_id_lock
= PTHREAD_MUTEX_INITIALIZER
;
93 static const char *lttng_viewer_command_str(lttng_viewer_command cmd
)
96 case LTTNG_VIEWER_CONNECT
:
98 case LTTNG_VIEWER_LIST_SESSIONS
:
99 return "LIST_SESSIONS";
100 case LTTNG_VIEWER_ATTACH_SESSION
:
101 return "ATTACH_SESSION";
102 case LTTNG_VIEWER_GET_NEXT_INDEX
:
103 return "GET_NEXT_INDEX";
104 case LTTNG_VIEWER_GET_PACKET
:
106 case LTTNG_VIEWER_GET_METADATA
:
107 return "GET_METADATA";
108 case LTTNG_VIEWER_GET_NEW_STREAMS
:
109 return "GET_NEW_STREAMS";
110 case LTTNG_VIEWER_CREATE_SESSION
:
111 return "CREATE_SESSION";
112 case LTTNG_VIEWER_DETACH_SESSION
:
113 return "DETACH_SESSION";
120 lttng_viewer_next_index_return_code_str(enum lttng_viewer_next_index_return_code code
)
123 case LTTNG_VIEWER_INDEX_OK
:
125 case LTTNG_VIEWER_INDEX_RETRY
:
126 return "INDEX_RETRY";
127 case LTTNG_VIEWER_INDEX_HUP
:
129 case LTTNG_VIEWER_INDEX_ERR
:
131 case LTTNG_VIEWER_INDEX_INACTIVE
:
132 return "INDEX_INACTIVE";
133 case LTTNG_VIEWER_INDEX_EOF
:
140 static const char *lttng_viewer_attach_return_code_str(enum lttng_viewer_attach_return_code code
)
143 case LTTNG_VIEWER_ATTACH_OK
:
145 case LTTNG_VIEWER_ATTACH_ALREADY
:
146 return "ATTACH_ALREADY";
147 case LTTNG_VIEWER_ATTACH_UNK
:
149 case LTTNG_VIEWER_ATTACH_NOT_LIVE
:
150 return "ATTACH_NOT_LIVE";
151 case LTTNG_VIEWER_ATTACH_SEEK_ERR
:
152 return "ATTACH_SEEK_ERR";
153 case LTTNG_VIEWER_ATTACH_NO_SESSION
:
154 return "ATTACH_NO_SESSION";
161 lttng_viewer_get_packet_return_code_str(enum lttng_viewer_get_packet_return_code code
)
164 case LTTNG_VIEWER_GET_PACKET_OK
:
165 return "GET_PACKET_OK";
166 case LTTNG_VIEWER_GET_PACKET_RETRY
:
167 return "GET_PACKET_RETRY";
168 case LTTNG_VIEWER_GET_PACKET_ERR
:
169 return "GET_PACKET_ERR";
170 case LTTNG_VIEWER_GET_PACKET_EOF
:
171 return "GET_PACKET_EOF";
180 static void cleanup_relayd_live()
188 * Receive a request buffer using a given socket, destination allocated buffer
191 * Return the size of the received message or else a negative value on error
192 * with errno being set by recvmsg() syscall.
194 static ssize_t
recv_request(struct lttcomm_sock
*sock
, void *buf
, size_t size
)
198 ret
= sock
->ops
->recvmsg(sock
, buf
, size
, 0);
199 if (ret
< 0 || ret
!= size
) {
201 /* Orderly shutdown. Not necessary to print an error. */
202 DBG("Socket %d did an orderly shutdown", sock
->fd
);
204 ERR("Relay failed to receive request.");
213 * Send a response buffer using a given socket, source allocated buffer of
216 * Return the size of the sent message or else a negative value on error with
217 * errno being set by sendmsg() syscall.
219 static ssize_t
send_response(struct lttcomm_sock
*sock
, void *buf
, size_t size
)
223 ret
= sock
->ops
->sendmsg(sock
, buf
, size
, 0);
225 ERR("Relayd failed to send response.");
232 * Atomically check if new streams got added in one of the sessions attached
233 * and reset the flag to 0.
235 * Returns 1 if new streams got added, 0 if nothing changed, a negative value
238 static int check_new_streams(struct relay_connection
*conn
)
240 struct relay_session
*session
;
243 if (!conn
->viewer_session
) {
248 lttng::urcu::read_lock_guard read_lock
;
249 cds_list_for_each_entry_rcu(
250 session
, &conn
->viewer_session
->session_list
, viewer_session_node
)
252 if (!session_get(session
)) {
256 ret
= uatomic_read(&session
->new_streams
);
257 session_put(session
);
265 DBG("Viewer connection has%s new streams: socket_fd = %d",
266 ret
== 0 ? " no" : "",
272 * Send viewer streams to the given socket. The ignore_sent_flag indicates if
273 * this function should ignore the sent flag or not.
275 * Return 0 on success or else a negative value.
278 send_viewer_streams(struct lttcomm_sock
*sock
, uint64_t session_id
, unsigned int ignore_sent_flag
)
281 struct lttng_ht_iter iter
;
282 struct relay_viewer_stream
*vstream
;
285 lttng::urcu::read_lock_guard read_lock
;
287 cds_lfht_for_each_entry (
288 viewer_streams_ht
->ht
, &iter
.iter
, vstream
, stream_n
.node
) {
289 struct ctf_trace
*ctf_trace
;
290 struct lttng_viewer_stream send_stream
= {};
292 health_code_update();
294 if (!viewer_stream_get(vstream
)) {
298 pthread_mutex_lock(&vstream
->stream
->lock
);
299 /* Ignore if not the same session. */
300 if (vstream
->stream
->trace
->session
->id
!= session_id
||
301 (!ignore_sent_flag
&& vstream
->sent_flag
)) {
302 pthread_mutex_unlock(&vstream
->stream
->lock
);
303 viewer_stream_put(vstream
);
307 ctf_trace
= vstream
->stream
->trace
;
308 send_stream
.id
= htobe64(vstream
->stream
->stream_handle
);
309 send_stream
.ctf_trace_id
= htobe64(ctf_trace
->id
);
310 send_stream
.metadata_flag
= htobe32(vstream
->stream
->is_metadata
);
311 if (lttng_strncpy(send_stream
.path_name
,
313 sizeof(send_stream
.path_name
))) {
314 pthread_mutex_unlock(&vstream
->stream
->lock
);
315 viewer_stream_put(vstream
);
316 ret
= -1; /* Error. */
319 if (lttng_strncpy(send_stream
.channel_name
,
320 vstream
->channel_name
,
321 sizeof(send_stream
.channel_name
))) {
322 pthread_mutex_unlock(&vstream
->stream
->lock
);
323 viewer_stream_put(vstream
);
324 ret
= -1; /* Error. */
328 DBG("Sending stream %" PRIu64
" to viewer", vstream
->stream
->stream_handle
);
329 vstream
->sent_flag
= true;
330 pthread_mutex_unlock(&vstream
->stream
->lock
);
332 ret
= send_response(sock
, &send_stream
, sizeof(send_stream
));
333 viewer_stream_put(vstream
);
347 * Create every viewer stream possible for the given session with the seek
348 * type. Three counters *can* be return which are in order the total amount of
349 * viewer stream of the session, the number of unsent stream and the number of
350 * stream created. Those counters can be NULL and thus will be ignored.
352 * session must be locked to ensure that we see either none or all initial
353 * streams for a session, but no intermediate state..
355 * Return 0 on success or else a negative value.
357 static int make_viewer_streams(struct relay_session
*relay_session
,
358 struct relay_viewer_session
*viewer_session
,
359 enum lttng_viewer_seek seek_t
,
362 uint32_t *nb_created
,
366 struct lttng_ht_iter iter
;
367 struct ctf_trace
*ctf_trace
;
368 struct relay_stream
*relay_stream
= nullptr;
370 LTTNG_ASSERT(relay_session
);
371 ASSERT_LOCKED(relay_session
->lock
);
373 if (relay_session
->connection_closed
) {
378 * Create viewer streams for relay streams that are ready to be
379 * used for a the given session id only.
382 lttng::urcu::read_lock_guard read_lock
;
384 cds_lfht_for_each_entry (
385 relay_session
->ctf_traces_ht
->ht
, &iter
.iter
, ctf_trace
, node
.node
) {
386 bool trace_has_metadata_stream
= false;
388 health_code_update();
390 if (!ctf_trace_get(ctf_trace
)) {
395 * Iterate over all the streams of the trace to see if we have a
398 cds_list_for_each_entry_rcu(
399 relay_stream
, &ctf_trace
->stream_list
, stream_node
)
401 bool is_metadata_stream
;
403 pthread_mutex_lock(&relay_stream
->lock
);
404 is_metadata_stream
= relay_stream
->is_metadata
;
405 pthread_mutex_unlock(&relay_stream
->lock
);
407 if (is_metadata_stream
) {
408 trace_has_metadata_stream
= true;
413 relay_stream
= nullptr;
416 * If there is no metadata stream in this trace at the moment
417 * and we never sent one to the viewer, skip the trace. We
418 * accept that the viewer will not see this trace at all.
420 if (!trace_has_metadata_stream
&&
421 !ctf_trace
->metadata_stream_sent_to_viewer
) {
422 ctf_trace_put(ctf_trace
);
426 cds_list_for_each_entry_rcu(
427 relay_stream
, &ctf_trace
->stream_list
, stream_node
)
429 struct relay_viewer_stream
*viewer_stream
;
431 if (!stream_get(relay_stream
)) {
435 pthread_mutex_lock(&relay_stream
->lock
);
437 * stream published is protected by the session lock.
439 if (!relay_stream
->published
) {
443 viewer_stream_get_by_id(relay_stream
->stream_handle
);
444 if (!viewer_stream
) {
445 struct lttng_trace_chunk
*viewer_stream_trace_chunk
=
449 * Save that we sent the metadata stream to the
450 * viewer. So that we know what trace the viewer
453 if (relay_stream
->is_metadata
) {
454 ctf_trace
->metadata_stream_sent_to_viewer
= true;
458 * If a rotation is ongoing, use a copy of the
459 * relay stream's chunk to ensure the stream
462 * Otherwise, the viewer session's current trace
463 * chunk can be used safely.
465 if ((relay_stream
->ongoing_rotation
.is_set
||
466 session_has_ongoing_rotation(relay_session
)) &&
467 relay_stream
->trace_chunk
) {
468 viewer_stream_trace_chunk
= lttng_trace_chunk_copy(
469 relay_stream
->trace_chunk
);
470 if (!viewer_stream_trace_chunk
) {
472 ctf_trace_put(ctf_trace
);
477 * Transition the viewer session into the newest
478 * trace chunk available.
480 if (!lttng_trace_chunk_ids_equal(
481 viewer_session
->current_trace_chunk
,
482 relay_stream
->trace_chunk
)) {
483 ret
= viewer_session_set_trace_chunk_copy(
485 relay_stream
->trace_chunk
);
488 ctf_trace_put(ctf_trace
);
493 if (relay_stream
->trace_chunk
) {
495 * If the corresponding relay
496 * stream's trace chunk is set,
497 * the viewer stream will be
500 * Note that a relay stream can
501 * have a NULL output trace
502 * chunk (for instance, after a
503 * clear against a stopped
506 const bool reference_acquired
=
507 lttng_trace_chunk_get(
509 ->current_trace_chunk
);
511 LTTNG_ASSERT(reference_acquired
);
512 viewer_stream_trace_chunk
=
513 viewer_session
->current_trace_chunk
;
517 viewer_stream
= viewer_stream_create(
518 relay_stream
, viewer_stream_trace_chunk
, seek_t
);
519 lttng_trace_chunk_put(viewer_stream_trace_chunk
);
520 viewer_stream_trace_chunk
= nullptr;
521 if (!viewer_stream
) {
523 ctf_trace_put(ctf_trace
);
528 /* Update number of created stream counter. */
532 * Ensure a self-reference is preserved even
533 * after we have put our local reference.
535 if (!viewer_stream_get(viewer_stream
)) {
536 ERR("Unable to get self-reference on viewer stream, logic error.");
540 if (!viewer_stream
->sent_flag
&& nb_unsent
) {
541 /* Update number of unsent stream counter. */
545 /* Update number of total stream counter. */
547 if (relay_stream
->is_metadata
) {
548 if (!relay_stream
->closed
||
549 relay_stream
->metadata_received
>
550 viewer_stream
->metadata_sent
) {
554 if (!relay_stream
->closed
||
555 !(((int64_t) (relay_stream
->prev_data_seq
-
556 relay_stream
->last_net_seq_num
)) >=
562 /* Put local reference. */
563 viewer_stream_put(viewer_stream
);
565 pthread_mutex_unlock(&relay_stream
->lock
);
566 stream_put(relay_stream
);
568 relay_stream
= nullptr;
569 ctf_trace_put(ctf_trace
);
578 pthread_mutex_unlock(&relay_stream
->lock
);
579 stream_put(relay_stream
);
585 int relayd_live_stop()
587 /* Stop dispatch thread */
588 CMM_STORE_SHARED(live_dispatch_thread_exit
, 1);
589 futex_nto1_wake(&viewer_conn_queue
.futex
);
593 static int create_sock(void *data
, int *out_fd
)
596 struct lttcomm_sock
*sock
= (lttcomm_sock
*) data
;
598 ret
= lttcomm_create_sock(sock
);
608 static int close_sock(void *data
, int *in_fd
__attribute__((unused
)))
610 struct lttcomm_sock
*sock
= (lttcomm_sock
*) data
;
612 return sock
->ops
->close(sock
);
615 static int accept_sock(void *data
, int *out_fd
)
618 /* Socks is an array of in_sock, out_sock. */
619 struct lttcomm_sock
**socks
= (lttcomm_sock
**) data
;
620 struct lttcomm_sock
*in_sock
= socks
[0];
622 socks
[1] = in_sock
->ops
->accept(in_sock
);
627 *out_fd
= socks
[1]->fd
;
632 static struct lttcomm_sock
*accept_live_sock(struct lttcomm_sock
*listening_sock
, const char *name
)
635 struct lttcomm_sock
*socks
[2] = { listening_sock
, nullptr };
636 struct lttcomm_sock
*new_sock
= nullptr;
638 ret
= fd_tracker_open_unsuspendable_fd(
639 the_fd_tracker
, &out_fd
, (const char **) &name
, 1, accept_sock
, &socks
);
644 DBG("%s accepted, socket %d", name
, new_sock
->fd
);
650 * Create and init socket from uri.
652 static struct lttcomm_sock
*init_socket(struct lttng_uri
*uri
, const char *name
)
655 struct lttcomm_sock
*sock
= nullptr;
656 char uri_str
[LTTNG_PATH_MAX
];
657 char *formated_name
= nullptr;
659 sock
= lttcomm_alloc_sock_from_uri(uri
);
660 if (sock
== nullptr) {
661 ERR("Allocating socket");
666 * Don't fail to create the socket if the name can't be built as it is
667 * only used for debugging purposes.
669 ret
= uri_to_str_url(uri
, uri_str
, sizeof(uri_str
));
670 uri_str
[sizeof(uri_str
) - 1] = '\0';
672 ret
= asprintf(&formated_name
, "%s socket @ %s", name
, uri_str
);
674 formated_name
= nullptr;
678 ret
= fd_tracker_open_unsuspendable_fd(the_fd_tracker
,
680 (const char **) (formated_name
? &formated_name
:
686 PERROR("Failed to create \"%s\" socket", formated_name
?: "Unknown");
689 DBG("Listening on %s socket %d", name
, sock
->fd
);
691 ret
= sock
->ops
->bind(sock
);
693 PERROR("Failed to bind lttng-live socket");
697 ret
= sock
->ops
->listen(sock
, -1);
707 lttcomm_destroy_sock(sock
);
714 * This thread manages the listening for new connections on the network
716 static void *thread_listener(void *data
__attribute__((unused
)))
718 int i
, ret
, err
= -1;
720 struct lttng_poll_event events
;
721 struct lttcomm_sock
*live_control_sock
;
723 DBG("[thread] Relay live listener started");
725 rcu_register_thread();
726 health_register(health_relayd
, HEALTH_RELAYD_TYPE_LIVE_LISTENER
);
728 health_code_update();
730 live_control_sock
= init_socket(live_uri
, "Live listener");
731 if (!live_control_sock
) {
732 goto error_sock_control
;
735 /* Pass 2 as size here for the thread quit pipe and control sockets. */
736 ret
= create_named_thread_poll_set(&events
, 2, "Live listener thread epoll");
738 goto error_create_poll
;
741 /* Add the control socket */
742 ret
= lttng_poll_add(&events
, live_control_sock
->fd
, LPOLLIN
| LPOLLRDHUP
);
747 lttng_relay_notify_ready();
749 if (testpoint(relayd_thread_live_listener
)) {
750 goto error_testpoint
;
754 health_code_update();
756 DBG("Listener accepting live viewers connections");
760 ret
= lttng_poll_wait(&events
, -1);
764 * Restart interrupted system call.
766 if (errno
== EINTR
) {
773 DBG("Relay new viewer connection received");
774 for (i
= 0; i
< nb_fd
; i
++) {
775 /* Fetch once the poll data */
776 const auto revents
= LTTNG_POLL_GETEV(&events
, i
);
777 const auto pollfd
= LTTNG_POLL_GETFD(&events
, i
);
779 health_code_update();
781 /* Activity on thread quit pipe, exiting. */
782 if (relayd_is_thread_quit_pipe(pollfd
)) {
783 DBG("Activity on thread quit pipe");
788 if (revents
& LPOLLIN
) {
790 * A new connection is requested, therefore a
791 * viewer connection is allocated in this
792 * thread, enqueued to a global queue and
793 * dequeued (and freed) in the worker thread.
796 struct relay_connection
*new_conn
;
797 struct lttcomm_sock
*newsock
;
799 newsock
= accept_live_sock(live_control_sock
,
800 "Live socket to client");
802 PERROR("accepting control sock");
805 DBG("Relay viewer connection accepted socket %d", newsock
->fd
);
808 newsock
->fd
, SOL_SOCKET
, SO_REUSEADDR
, &val
, sizeof(val
));
810 PERROR("setsockopt inet");
811 lttcomm_destroy_sock(newsock
);
814 new_conn
= connection_create(newsock
, RELAY_CONNECTION_UNKNOWN
);
816 lttcomm_destroy_sock(newsock
);
819 /* Ownership assumed by the connection. */
822 /* Enqueue request for the dispatcher thread. */
823 cds_wfcq_head_ptr_t head
;
824 head
.h
= &viewer_conn_queue
.head
;
825 cds_wfcq_enqueue(head
, &viewer_conn_queue
.tail
, &new_conn
->qnode
);
828 * Wake the dispatch queue futex.
829 * Implicit memory barrier with the
830 * exchange in cds_wfcq_enqueue.
832 futex_nto1_wake(&viewer_conn_queue
.futex
);
833 } else if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
834 ERR("socket poll error");
837 ERR("Unexpected poll events %u for sock %d", revents
, pollfd
);
847 (void) fd_tracker_util_poll_clean(the_fd_tracker
, &events
);
849 if (live_control_sock
->fd
>= 0) {
850 int sock_fd
= live_control_sock
->fd
;
852 ret
= fd_tracker_close_unsuspendable_fd(
853 the_fd_tracker
, &sock_fd
, 1, close_sock
, live_control_sock
);
857 live_control_sock
->fd
= -1;
859 lttcomm_destroy_sock(live_control_sock
);
863 DBG("Live viewer listener thread exited with error");
865 health_unregister(health_relayd
);
866 rcu_unregister_thread();
867 DBG("Live viewer listener thread cleanup complete");
868 if (lttng_relay_stop_threads()) {
869 ERR("Error stopping threads");
875 * This thread manages the dispatching of the requests to worker threads
877 static void *thread_dispatcher(void *data
__attribute__((unused
)))
881 struct cds_wfcq_node
*node
;
882 struct relay_connection
*conn
= nullptr;
884 DBG("[thread] Live viewer relay dispatcher started");
886 health_register(health_relayd
, HEALTH_RELAYD_TYPE_LIVE_DISPATCHER
);
888 if (testpoint(relayd_thread_live_dispatcher
)) {
889 goto error_testpoint
;
892 health_code_update();
895 health_code_update();
897 /* Atomically prepare the queue futex */
898 futex_nto1_prepare(&viewer_conn_queue
.futex
);
900 if (CMM_LOAD_SHARED(live_dispatch_thread_exit
)) {
905 health_code_update();
907 /* Dequeue commands */
908 node
= cds_wfcq_dequeue_blocking(&viewer_conn_queue
.head
,
909 &viewer_conn_queue
.tail
);
910 if (node
== nullptr) {
911 DBG("Woken up but nothing in the live-viewer "
912 "relay command queue");
913 /* Continue thread execution */
916 conn
= lttng::utils::container_of(node
, &relay_connection::qnode
);
917 DBG("Dispatching viewer request waiting on sock %d", conn
->sock
->fd
);
920 * Inform worker thread of the new request. This
921 * call is blocking so we can be assured that
922 * the data will be read at some point in time
923 * or wait to the end of the world :)
925 ret
= lttng_write(live_conn_pipe
[1], &conn
, sizeof(conn
)); /* NOLINT sizeof
929 PERROR("write conn pipe");
930 connection_put(conn
);
933 } while (node
!= nullptr);
935 /* Futex wait on queue. Blocking call on futex() */
937 futex_nto1_wait(&viewer_conn_queue
.futex
);
941 /* Normal exit, no error */
948 ERR("Health error occurred in %s", __func__
);
950 health_unregister(health_relayd
);
951 DBG("Live viewer dispatch thread dying");
952 if (lttng_relay_stop_threads()) {
953 ERR("Error stopping threads");
959 * Establish connection with the viewer and check the versions.
961 * Return 0 on success or else negative value.
963 static int viewer_connect(struct relay_connection
*conn
)
966 struct lttng_viewer_connect reply
, msg
;
968 conn
->version_check_done
= true;
970 health_code_update();
972 ret
= recv_request(conn
->sock
, &msg
, sizeof(msg
));
977 health_code_update();
979 memset(&reply
, 0, sizeof(reply
));
980 reply
.major
= RELAYD_VERSION_COMM_MAJOR
;
981 reply
.minor
= RELAYD_VERSION_COMM_MINOR
;
983 /* Major versions must be the same */
984 if (reply
.major
!= be32toh(msg
.major
)) {
985 DBG("Incompatible major versions ([relayd] %u vs [client] %u)",
992 conn
->major
= reply
.major
;
993 /* We adapt to the lowest compatible version */
994 if (reply
.minor
<= be32toh(msg
.minor
)) {
995 conn
->minor
= reply
.minor
;
997 conn
->minor
= be32toh(msg
.minor
);
1000 if (be32toh(msg
.type
) == LTTNG_VIEWER_CLIENT_COMMAND
) {
1001 conn
->type
= RELAY_VIEWER_COMMAND
;
1002 } else if (be32toh(msg
.type
) == LTTNG_VIEWER_CLIENT_NOTIFICATION
) {
1003 conn
->type
= RELAY_VIEWER_NOTIFICATION
;
1005 ERR("Unknown connection type : %u", be32toh(msg
.type
));
1010 reply
.major
= htobe32(reply
.major
);
1011 reply
.minor
= htobe32(reply
.minor
);
1012 if (conn
->type
== RELAY_VIEWER_COMMAND
) {
1014 * Increment outside of htobe64 macro, because the argument can
1015 * be used more than once within the macro, and thus the
1016 * operation may be undefined.
1018 pthread_mutex_lock(&last_relay_viewer_session_id_lock
);
1019 last_relay_viewer_session_id
++;
1020 pthread_mutex_unlock(&last_relay_viewer_session_id_lock
);
1021 reply
.viewer_session_id
= htobe64(last_relay_viewer_session_id
);
1024 health_code_update();
1026 ret
= send_response(conn
->sock
, &reply
, sizeof(reply
));
1031 health_code_update();
1033 DBG("Version check done using protocol %u.%u", conn
->major
, conn
->minor
);
1041 * Send the viewer the list of current sessions.
1042 * We need to create a copy of the hash table content because otherwise
1043 * we cannot assume the number of entries stays the same between getting
1044 * the number of HT elements and iteration over the HT.
1046 * Return 0 on success or else a negative value.
1048 static int viewer_list_sessions(struct relay_connection
*conn
)
1051 struct lttng_viewer_list_sessions session_list
;
1052 struct lttng_ht_iter iter
;
1053 struct relay_session
*session
;
1054 struct lttng_viewer_session
*send_session_buf
= nullptr;
1055 uint32_t buf_count
= SESSION_BUF_DEFAULT_COUNT
;
1058 send_session_buf
= calloc
<lttng_viewer_session
>(SESSION_BUF_DEFAULT_COUNT
);
1059 if (!send_session_buf
) {
1064 lttng::urcu::read_lock_guard read_lock
;
1066 cds_lfht_for_each_entry (sessions_ht
->ht
, &iter
.iter
, session
, session_n
.node
) {
1067 struct lttng_viewer_session
*send_session
;
1069 health_code_update();
1071 pthread_mutex_lock(&session
->lock
);
1072 if (session
->connection_closed
) {
1073 /* Skip closed session */
1077 if (count
>= buf_count
) {
1078 struct lttng_viewer_session
*newbuf
;
1079 uint32_t new_buf_count
= buf_count
<< 1;
1081 newbuf
= (lttng_viewer_session
*) realloc(
1083 new_buf_count
* sizeof(*send_session_buf
));
1088 send_session_buf
= newbuf
;
1089 buf_count
= new_buf_count
;
1091 send_session
= &send_session_buf
[count
];
1092 if (lttng_strncpy(send_session
->session_name
,
1093 session
->session_name
,
1094 sizeof(send_session
->session_name
))) {
1098 if (lttng_strncpy(send_session
->hostname
,
1100 sizeof(send_session
->hostname
))) {
1104 send_session
->id
= htobe64(session
->id
);
1105 send_session
->live_timer
= htobe32(session
->live_timer
);
1106 if (session
->viewer_attached
) {
1107 send_session
->clients
= htobe32(1);
1109 send_session
->clients
= htobe32(0);
1111 send_session
->streams
= htobe32(session
->stream_count
);
1114 pthread_mutex_unlock(&session
->lock
);
1117 pthread_mutex_unlock(&session
->lock
);
1126 session_list
.sessions_count
= htobe32(count
);
1128 health_code_update();
1130 ret
= send_response(conn
->sock
, &session_list
, sizeof(session_list
));
1135 health_code_update();
1137 ret
= send_response(conn
->sock
, send_session_buf
, count
* sizeof(*send_session_buf
));
1141 health_code_update();
1145 free(send_session_buf
);
1150 * Send the viewer the list of current streams.
1152 static int viewer_get_new_streams(struct relay_connection
*conn
)
1154 int ret
, send_streams
= 0;
1155 uint32_t nb_created
= 0, nb_unsent
= 0, nb_streams
= 0, nb_total
= 0;
1156 struct lttng_viewer_new_streams_request request
;
1157 struct lttng_viewer_new_streams_response response
;
1158 struct relay_session
*session
= nullptr;
1159 uint64_t session_id
;
1160 bool closed
= false;
1164 health_code_update();
1166 /* Receive the request from the connected client. */
1167 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
1171 session_id
= be64toh(request
.session_id
);
1173 health_code_update();
1175 memset(&response
, 0, sizeof(response
));
1177 session
= session_get_by_id(session_id
);
1179 DBG("Relay session %" PRIu64
" not found", session_id
);
1180 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR
);
1184 if (!viewer_session_is_attached(conn
->viewer_session
, session
)) {
1185 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR
);
1190 * For any new stream, create it with LTTNG_VIEWER_SEEK_BEGINNING since
1191 * that at this point the client is already attached to the session.Aany
1192 * initial stream will have been created with the seek type at attach
1193 * time (for now most readers use the LTTNG_VIEWER_SEEK_LAST on attach).
1194 * Otherwise any event happening in a new stream between the attach and
1195 * a call to viewer_get_new_streams will be "lost" (never received) from
1196 * the viewer's point of view.
1198 pthread_mutex_lock(&session
->lock
);
1200 * If a session rotation is ongoing, do not attempt to open any
1201 * stream, because the chunk can be in an intermediate state
1202 * due to directory renaming.
1204 if (session_has_ongoing_rotation(session
)) {
1205 DBG("Relay session %" PRIu64
" rotation ongoing", session_id
);
1206 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_NO_NEW
);
1207 goto send_reply_unlock
;
1209 ret
= make_viewer_streams(session
,
1210 conn
->viewer_session
,
1211 LTTNG_VIEWER_SEEK_BEGINNING
,
1218 * This is caused by an internal error; propagate the negative
1219 * 'ret' to close the connection.
1221 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR
);
1222 goto send_reply_unlock
;
1225 uatomic_set(&session
->new_streams
, 0);
1227 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_OK
);
1229 /* Only send back the newly created streams with the unsent ones. */
1230 nb_streams
= nb_created
+ nb_unsent
;
1231 response
.streams_count
= htobe32(nb_streams
);
1234 * If the session is closed, HUP when there are no more streams
1237 if (closed
&& nb_total
== 0) {
1239 response
.streams_count
= 0;
1240 response
.status
= htobe32(LTTNG_VIEWER_NEW_STREAMS_HUP
);
1241 goto send_reply_unlock
;
1244 pthread_mutex_unlock(&session
->lock
);
1247 health_code_update();
1248 ret
= send_response(conn
->sock
, &response
, sizeof(response
));
1250 goto end_put_session
;
1252 health_code_update();
1255 * Unknown or empty session, just return gracefully, the viewer
1256 * knows what is happening.
1258 if (!send_streams
|| !nb_streams
) {
1260 goto end_put_session
;
1264 * Send stream and *DON'T* ignore the sent flag so every viewer
1265 * streams that were not sent from that point will be sent to
1268 ret
= send_viewer_streams(conn
->sock
, session_id
, 0);
1270 goto end_put_session
;
1275 session_put(session
);
1282 * Send the viewer the list of current sessions.
1284 static int viewer_attach_session(struct relay_connection
*conn
)
1286 int send_streams
= 0;
1288 uint32_t nb_streams
= 0;
1289 enum lttng_viewer_seek seek_type
;
1290 struct lttng_viewer_attach_session_request request
;
1291 struct lttng_viewer_attach_session_response response
;
1292 struct relay_session
*session
= nullptr;
1293 enum lttng_viewer_attach_return_code viewer_attach_status
;
1294 bool closed
= false;
1295 uint64_t session_id
;
1299 health_code_update();
1301 /* Receive the request from the connected client. */
1302 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
1307 session_id
= be64toh(request
.session_id
);
1309 health_code_update();
1311 memset(&response
, 0, sizeof(response
));
1313 if (!conn
->viewer_session
) {
1314 viewer_attach_status
= LTTNG_VIEWER_ATTACH_NO_SESSION
;
1315 DBG("Client trying to attach before creating a live viewer session, returning status=%s",
1316 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1320 session
= session_get_by_id(session_id
);
1322 viewer_attach_status
= LTTNG_VIEWER_ATTACH_UNK
;
1323 DBG("Relay session %" PRIu64
" not found, returning status=%s",
1325 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1328 DBG("Attach relay session ID %" PRIu64
" received", session_id
);
1330 pthread_mutex_lock(&session
->lock
);
1331 if (session
->live_timer
== 0) {
1332 viewer_attach_status
= LTTNG_VIEWER_ATTACH_NOT_LIVE
;
1333 DBG("Relay session ID %" PRIu64
" is not a live session, returning status=%s",
1335 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1340 viewer_attach_status
= viewer_session_attach(conn
->viewer_session
, session
);
1341 if (viewer_attach_status
!= LTTNG_VIEWER_ATTACH_OK
) {
1342 DBG("Error attaching to relay session %" PRIu64
", returning status=%s",
1344 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1348 switch (be32toh(request
.seek
)) {
1349 case LTTNG_VIEWER_SEEK_BEGINNING
:
1350 case LTTNG_VIEWER_SEEK_LAST
:
1351 viewer_attach_status
= LTTNG_VIEWER_ATTACH_OK
;
1352 seek_type
= (lttng_viewer_seek
) be32toh(request
.seek
);
1355 ERR("Wrong seek parameter for relay session %" PRIu64
", returning status=%s",
1357 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1358 viewer_attach_status
= LTTNG_VIEWER_ATTACH_SEEK_ERR
;
1364 * If a session rotation is ongoing, do not attempt to open any
1365 * stream, because the chunk can be in an intermediate state
1366 * due to directory renaming.
1368 if (session_has_ongoing_rotation(session
)) {
1369 DBG("Relay session %" PRIu64
" rotation ongoing", session_id
);
1374 ret
= make_viewer_streams(
1375 session
, conn
->viewer_session
, seek_type
, &nb_streams
, nullptr, nullptr, &closed
);
1377 goto end_put_session
;
1379 pthread_mutex_unlock(&session
->lock
);
1380 session_put(session
);
1383 response
.streams_count
= htobe32(nb_streams
);
1385 * If the session is closed when the viewer is attaching, it
1386 * means some of the streams may have been concurrently removed,
1387 * so we don't allow the viewer to attach, even if there are
1388 * streams available.
1392 response
.streams_count
= 0;
1393 viewer_attach_status
= LTTNG_VIEWER_ATTACH_UNK
;
1394 ERR("Session %" PRIu64
" is closed, returning status=%s",
1396 lttng_viewer_attach_return_code_str(viewer_attach_status
));
1401 health_code_update();
1403 response
.status
= htobe32((uint32_t) viewer_attach_status
);
1405 ret
= send_response(conn
->sock
, &response
, sizeof(response
));
1407 goto end_put_session
;
1409 health_code_update();
1412 * Unknown or empty session, just return gracefully, the viewer
1413 * knows what is happening.
1415 if (!send_streams
|| !nb_streams
) {
1417 goto end_put_session
;
1420 /* Send stream and ignore the sent flag. */
1421 ret
= send_viewer_streams(conn
->sock
, session_id
, 1);
1423 goto end_put_session
;
1428 pthread_mutex_unlock(&session
->lock
);
1429 session_put(session
);
1436 * Open the index file if needed for the given vstream.
1438 * If an index file is successfully opened, the vstream will set it as its
1439 * current index file.
1441 * Return 0 on success, a negative value on error (-ENOENT if not ready yet).
1443 * Called with rstream lock held.
1445 static int try_open_index(struct relay_viewer_stream
*vstream
, struct relay_stream
*rstream
)
1448 const uint32_t connection_major
= rstream
->trace
->session
->major
;
1449 const uint32_t connection_minor
= rstream
->trace
->session
->minor
;
1450 enum lttng_trace_chunk_status chunk_status
;
1452 if (vstream
->index_file
) {
1457 * First time, we open the index file and at least one index is ready.
1459 if (rstream
->index_received_seqcount
== 0 || !vstream
->stream_file
.trace_chunk
) {
1464 chunk_status
= lttng_index_file_create_from_trace_chunk_read_only(
1465 vstream
->stream_file
.trace_chunk
,
1467 rstream
->channel_name
,
1468 rstream
->tracefile_size
,
1469 vstream
->current_tracefile_id
,
1470 lttng_to_index_major(connection_major
, connection_minor
),
1471 lttng_to_index_minor(connection_major
, connection_minor
),
1473 &vstream
->index_file
);
1474 if (chunk_status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
1475 if (chunk_status
== LTTNG_TRACE_CHUNK_STATUS_NO_FILE
) {
1487 * Check the status of the index for the given stream. This function
1488 * updates the index structure if needed and can put (close) the vstream
1489 * in the HUP situation.
1491 * Return 0 means that we can proceed with the index. A value of 1 means
1492 * that the index has been updated and is ready to be sent to the
1493 * client. A negative value indicates an error that can't be handled.
1495 * Called with rstream lock held.
1497 static int check_index_status(struct relay_viewer_stream
*vstream
,
1498 struct relay_stream
*rstream
,
1499 struct ctf_trace
*trace
,
1500 struct lttng_viewer_index
*index
)
1504 DBG("Check index status: index_received_seqcount %" PRIu64
" "
1505 "index_sent_seqcount %" PRIu64
" "
1506 "for stream %" PRIu64
,
1507 rstream
->index_received_seqcount
,
1508 vstream
->index_sent_seqcount
,
1509 vstream
->stream
->stream_handle
);
1510 if ((trace
->session
->connection_closed
|| rstream
->closed
) &&
1511 rstream
->index_received_seqcount
== vstream
->index_sent_seqcount
) {
1513 * Last index sent and session connection or relay
1514 * stream are closed.
1516 index
->status
= LTTNG_VIEWER_INDEX_HUP
;
1517 DBG("Check index status: Connection or stream are closed, stream %" PRIu64
1518 ",connection-closed=%d, relay-stream-closed=%d, returning status=%s",
1519 vstream
->stream
->stream_handle
,
1520 trace
->session
->connection_closed
,
1522 lttng_viewer_next_index_return_code_str(
1523 (enum lttng_viewer_next_index_return_code
) index
->status
));
1525 } else if (rstream
->beacon_ts_end
!= -1ULL &&
1526 (rstream
->index_received_seqcount
== 0 ||
1527 (vstream
->index_sent_seqcount
!= 0 &&
1528 rstream
->index_received_seqcount
<= vstream
->index_sent_seqcount
))) {
1530 * We've received a synchronization beacon and the last index
1531 * available has been sent, the index for now is inactive.
1533 * In this case, we have received a beacon which allows us to
1534 * inform the client of a time interval during which we can
1535 * guarantee that there are no events to read (and never will
1538 * The sent seqcount can grow higher than receive seqcount on
1539 * clear because the rotation performed by clear will push
1540 * the index_sent_seqcount ahead (see
1541 * viewer_stream_sync_tracefile_array_tail) and skip over
1542 * packet sequence numbers.
1544 index
->status
= LTTNG_VIEWER_INDEX_INACTIVE
;
1545 index
->timestamp_end
= htobe64(rstream
->beacon_ts_end
);
1546 index
->stream_id
= htobe64(rstream
->ctf_stream_id
);
1547 DBG("Check index status: inactive with beacon, for stream %" PRIu64
1548 ", returning status=%s",
1549 vstream
->stream
->stream_handle
,
1550 lttng_viewer_next_index_return_code_str(
1551 (enum lttng_viewer_next_index_return_code
) index
->status
));
1553 } else if (rstream
->index_received_seqcount
== 0 ||
1554 (vstream
->index_sent_seqcount
!= 0 &&
1555 rstream
->index_received_seqcount
<= vstream
->index_sent_seqcount
)) {
1557 * This checks whether received <= sent seqcount. In
1558 * this case, we have not received a beacon. Therefore,
1559 * we can only ask the client to retry later.
1561 * The sent seqcount can grow higher than receive seqcount on
1562 * clear because the rotation performed by clear will push
1563 * the index_sent_seqcount ahead (see
1564 * viewer_stream_sync_tracefile_array_tail) and skip over
1565 * packet sequence numbers.
1567 index
->status
= LTTNG_VIEWER_INDEX_RETRY
;
1568 DBG("Check index status:"
1569 "did not received beacon for stream %" PRIu64
", returning status=%s",
1570 vstream
->stream
->stream_handle
,
1571 lttng_viewer_next_index_return_code_str(
1572 (enum lttng_viewer_next_index_return_code
) index
->status
));
1574 } else if (!tracefile_array_seq_in_file(rstream
->tfa
,
1575 vstream
->current_tracefile_id
,
1576 vstream
->index_sent_seqcount
)) {
1578 * The next index we want to send cannot be read either
1579 * because we need to perform a rotation, or due to
1580 * the producer having overwritten its trace file.
1582 DBG("Viewer stream %" PRIu64
" rotation", vstream
->stream
->stream_handle
);
1583 ret
= viewer_stream_rotate(vstream
);
1585 /* EOF across entire stream. */
1586 index
->status
= LTTNG_VIEWER_INDEX_HUP
;
1587 DBG("Check index status:"
1588 "reached end of file for stream %" PRIu64
", returning status=%s",
1589 vstream
->stream
->stream_handle
,
1590 lttng_viewer_next_index_return_code_str(
1591 (enum lttng_viewer_next_index_return_code
) index
->status
));
1595 * If we have been pushed due to overwrite, it
1596 * necessarily means there is data that can be read in
1597 * the stream. If we rotated because we reached the end
1598 * of a tracefile, it means the following tracefile
1599 * needs to contain at least one index, else we would
1600 * have already returned LTTNG_VIEWER_INDEX_RETRY to the
1601 * viewer. The updated index_sent_seqcount needs to
1602 * point to a readable index entry now.
1604 * In the case where we "rotate" on a single file, we
1605 * can end up in a case where the requested index is
1606 * still unavailable.
1608 if (rstream
->tracefile_count
== 1 &&
1609 !tracefile_array_seq_in_file(rstream
->tfa
,
1610 vstream
->current_tracefile_id
,
1611 vstream
->index_sent_seqcount
)) {
1612 index
->status
= LTTNG_VIEWER_INDEX_RETRY
;
1613 DBG("Check index status:"
1614 "tracefile array sequence number %" PRIu64
1615 " not in file for stream %" PRIu64
", returning status=%s",
1616 vstream
->index_sent_seqcount
,
1617 vstream
->stream
->stream_handle
,
1618 lttng_viewer_next_index_return_code_str(
1619 (enum lttng_viewer_next_index_return_code
) index
->status
));
1622 LTTNG_ASSERT(tracefile_array_seq_in_file(
1623 rstream
->tfa
, vstream
->current_tracefile_id
, vstream
->index_sent_seqcount
));
1625 /* ret == 0 means successful so we continue. */
1630 viewer_stream_put(vstream
);
1635 static void viewer_stream_rotate_to_trace_chunk(struct relay_viewer_stream
*vstream
,
1636 struct lttng_trace_chunk
*new_trace_chunk
)
1638 lttng_trace_chunk_put(vstream
->stream_file
.trace_chunk
);
1640 if (new_trace_chunk
) {
1641 const bool acquired_reference
= lttng_trace_chunk_get(new_trace_chunk
);
1643 LTTNG_ASSERT(acquired_reference
);
1646 vstream
->stream_file
.trace_chunk
= new_trace_chunk
;
1647 viewer_stream_sync_tracefile_array_tail(vstream
);
1648 viewer_stream_close_files(vstream
);
1652 * Send the next index for a stream.
1654 * Return 0 on success or else a negative value.
1656 static int viewer_get_next_index(struct relay_connection
*conn
)
1659 struct lttng_viewer_get_next_index request_index
;
1660 struct lttng_viewer_index viewer_index
;
1661 struct ctf_packet_index packet_index
;
1662 struct relay_viewer_stream
*vstream
= nullptr;
1663 struct relay_stream
*rstream
= nullptr;
1664 struct ctf_trace
*ctf_trace
= nullptr;
1665 struct relay_viewer_stream
*metadata_viewer_stream
= nullptr;
1666 bool viewer_stream_and_session_in_same_chunk
, viewer_stream_one_rotation_behind
;
1667 uint64_t stream_file_chunk_id
= -1ULL, viewer_session_chunk_id
= -1ULL;
1668 enum lttng_trace_chunk_status status
;
1669 bool attached_sessions_have_new_streams
= false;
1673 memset(&viewer_index
, 0, sizeof(viewer_index
));
1674 health_code_update();
1676 ret
= recv_request(conn
->sock
, &request_index
, sizeof(request_index
));
1680 health_code_update();
1682 vstream
= viewer_stream_get_by_id(be64toh(request_index
.stream_id
));
1684 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1685 DBG("Client requested index of unknown stream id %" PRIu64
", returning status=%s",
1686 (uint64_t) be64toh(request_index
.stream_id
),
1687 lttng_viewer_next_index_return_code_str(
1688 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1692 /* Use back. ref. Protected by refcounts. */
1693 rstream
= vstream
->stream
;
1694 ctf_trace
= rstream
->trace
;
1696 /* metadata_viewer_stream may be NULL. */
1697 metadata_viewer_stream
= ctf_trace_get_viewer_metadata_stream(ctf_trace
);
1700 * Hold the session lock to protect against concurrent changes
1701 * to the chunk files (e.g. rename done by clear), which are
1702 * protected by the session ongoing rotation state. Those are
1703 * synchronized with the session lock.
1705 pthread_mutex_lock(&rstream
->trace
->session
->lock
);
1706 pthread_mutex_lock(&rstream
->lock
);
1709 * The viewer should not ask for index on metadata stream.
1711 if (rstream
->is_metadata
) {
1712 viewer_index
.status
= LTTNG_VIEWER_INDEX_HUP
;
1713 DBG("Client requested index of a metadata stream id %" PRIu64
1714 ", returning status=%s",
1715 (uint64_t) be64toh(request_index
.stream_id
),
1716 lttng_viewer_next_index_return_code_str(
1717 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1721 ret
= check_new_streams(conn
);
1723 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1724 ERR("Error checking for new streams in the attached sessions, returning status=%s",
1725 lttng_viewer_next_index_return_code_str(
1726 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1728 } else if (ret
== 1) {
1729 attached_sessions_have_new_streams
= true;
1732 if (rstream
->ongoing_rotation
.is_set
) {
1733 /* Rotation is ongoing, try again later. */
1734 viewer_index
.status
= LTTNG_VIEWER_INDEX_RETRY
;
1735 DBG("Client requested index for stream id %" PRIu64
1736 " while a stream rotation is ongoing, returning status=%s",
1737 (uint64_t) be64toh(request_index
.stream_id
),
1738 lttng_viewer_next_index_return_code_str(
1739 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1743 if (session_has_ongoing_rotation(rstream
->trace
->session
)) {
1744 /* Rotation is ongoing, try again later. */
1745 viewer_index
.status
= LTTNG_VIEWER_INDEX_RETRY
;
1746 DBG("Client requested index for stream id %" PRIu64
1747 " while a session rotation is ongoing, returning status=%s",
1748 (uint64_t) be64toh(request_index
.stream_id
),
1749 lttng_viewer_next_index_return_code_str(
1750 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1755 * Transition the viewer session into the newest trace chunk available.
1757 if (!lttng_trace_chunk_ids_equal(conn
->viewer_session
->current_trace_chunk
,
1758 rstream
->trace_chunk
)) {
1759 DBG("Relay stream and viewer chunk ids differ");
1761 ret
= viewer_session_set_trace_chunk_copy(conn
->viewer_session
,
1762 rstream
->trace_chunk
);
1764 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1765 ERR("Error copying trace chunk for stream id %" PRIu64
1766 ", returning status=%s",
1767 (uint64_t) be64toh(request_index
.stream_id
),
1768 lttng_viewer_next_index_return_code_str(
1769 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1775 * Transition the viewer stream into the latest trace chunk available.
1777 * Note that the stream must _not_ rotate in one precise condition:
1778 * the relay stream has rotated to a NULL trace chunk and the viewer
1779 * stream is consuming the trace chunk that was active just before
1780 * that rotation to NULL.
1782 * This allows clients to consume all the packets of a trace chunk
1783 * after a session's destruction.
1785 if (vstream
->stream_file
.trace_chunk
) {
1786 status
= lttng_trace_chunk_get_id(vstream
->stream_file
.trace_chunk
,
1787 &stream_file_chunk_id
);
1788 LTTNG_ASSERT(status
== LTTNG_TRACE_CHUNK_STATUS_OK
);
1790 if (conn
->viewer_session
->current_trace_chunk
) {
1791 status
= lttng_trace_chunk_get_id(conn
->viewer_session
->current_trace_chunk
,
1792 &viewer_session_chunk_id
);
1793 LTTNG_ASSERT(status
== LTTNG_TRACE_CHUNK_STATUS_OK
);
1796 viewer_stream_and_session_in_same_chunk
= lttng_trace_chunk_ids_equal(
1797 conn
->viewer_session
->current_trace_chunk
, vstream
->stream_file
.trace_chunk
);
1798 viewer_stream_one_rotation_behind
= rstream
->completed_rotation_count
==
1799 vstream
->last_seen_rotation_count
+ 1;
1801 if (viewer_stream_and_session_in_same_chunk
) {
1802 DBG("Transition to latest chunk check (%s -> %s): Same chunk, no need to rotate",
1803 vstream
->stream_file
.trace_chunk
?
1804 std::to_string(stream_file_chunk_id
).c_str() :
1806 conn
->viewer_session
->current_trace_chunk
?
1807 std::to_string(viewer_session_chunk_id
).c_str() :
1809 } else if (viewer_stream_one_rotation_behind
&& !rstream
->trace_chunk
) {
1810 DBG("Transition to latest chunk check (%s -> %s): One chunk behind relay stream which is being destroyed, no need to rotate",
1811 vstream
->stream_file
.trace_chunk
?
1812 std::to_string(stream_file_chunk_id
).c_str() :
1814 conn
->viewer_session
->current_trace_chunk
?
1815 std::to_string(viewer_session_chunk_id
).c_str() :
1818 DBG("Transition to latest chunk check (%s -> %s): Viewer stream chunk ID and viewer session chunk ID differ, rotating viewer stream",
1819 vstream
->stream_file
.trace_chunk
?
1820 std::to_string(stream_file_chunk_id
).c_str() :
1822 conn
->viewer_session
->current_trace_chunk
?
1823 std::to_string(viewer_session_chunk_id
).c_str() :
1826 viewer_stream_rotate_to_trace_chunk(vstream
,
1827 conn
->viewer_session
->current_trace_chunk
);
1828 vstream
->last_seen_rotation_count
= rstream
->completed_rotation_count
;
1831 ret
= check_index_status(vstream
, rstream
, ctf_trace
, &viewer_index
);
1834 } else if (ret
== 1) {
1836 * We have no index to send and check_index_status has populated
1837 * viewer_index's status.
1842 /* At this point, ret is 0 thus we will be able to read the index. */
1845 /* Try to open an index if one is needed for that stream. */
1846 ret
= try_open_index(vstream
, rstream
);
1847 if (ret
== -ENOENT
) {
1848 if (rstream
->closed
) {
1849 viewer_index
.status
= LTTNG_VIEWER_INDEX_HUP
;
1850 DBG("Cannot open index for stream id %" PRIu64
1851 "stream is closed, returning status=%s",
1852 (uint64_t) be64toh(request_index
.stream_id
),
1853 lttng_viewer_next_index_return_code_str(
1854 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1857 viewer_index
.status
= LTTNG_VIEWER_INDEX_RETRY
;
1858 DBG("Cannot open index for stream id %" PRIu64
", returning status=%s",
1859 (uint64_t) be64toh(request_index
.stream_id
),
1860 lttng_viewer_next_index_return_code_str(
1861 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1866 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1867 ERR("Error opening index for stream id %" PRIu64
", returning status=%s",
1868 (uint64_t) be64toh(request_index
.stream_id
),
1869 lttng_viewer_next_index_return_code_str(
1870 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1875 * vstream->stream_fd may be NULL if it has been closed by
1876 * tracefile rotation, or if we are at the beginning of the
1877 * stream. We open the data stream file here to protect against
1878 * overwrite caused by tracefile rotation (in association with
1879 * unlink performed before overwrite).
1881 if (!vstream
->stream_file
.handle
) {
1882 char file_path
[LTTNG_PATH_MAX
];
1883 struct fs_handle
*fs_handle
;
1885 ret
= utils_stream_file_path(rstream
->path_name
,
1886 rstream
->channel_name
,
1887 rstream
->tracefile_size
,
1888 vstream
->current_tracefile_id
,
1897 * It is possible the the file we are trying to open is
1898 * missing if the stream has been closed (application exits with
1899 * per-pid buffers) and a clear command has been performed.
1901 status
= lttng_trace_chunk_open_fs_handle(
1902 vstream
->stream_file
.trace_chunk
, file_path
, O_RDONLY
, 0, &fs_handle
, true);
1903 if (status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
1904 if (status
== LTTNG_TRACE_CHUNK_STATUS_NO_FILE
&& rstream
->closed
) {
1905 viewer_index
.status
= LTTNG_VIEWER_INDEX_HUP
;
1906 DBG("Cannot find trace chunk file and stream is closed for stream id %" PRIu64
1907 ", returning status=%s",
1908 (uint64_t) be64toh(request_index
.stream_id
),
1909 lttng_viewer_next_index_return_code_str(
1910 (enum lttng_viewer_next_index_return_code
)
1911 viewer_index
.status
));
1914 PERROR("Failed to open trace file for viewer stream");
1917 vstream
->stream_file
.handle
= fs_handle
;
1920 ret
= lttng_index_file_read(vstream
->index_file
, &packet_index
);
1922 viewer_index
.status
= LTTNG_VIEWER_INDEX_ERR
;
1923 ERR("Relay error reading index file for stream id %" PRIu64
", returning status=%s",
1924 (uint64_t) be64toh(request_index
.stream_id
),
1925 lttng_viewer_next_index_return_code_str(
1926 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1929 viewer_index
.status
= LTTNG_VIEWER_INDEX_OK
;
1930 DBG("Read index file for stream id %" PRIu64
", returning status=%s",
1931 (uint64_t) be64toh(request_index
.stream_id
),
1932 lttng_viewer_next_index_return_code_str(
1933 (enum lttng_viewer_next_index_return_code
) viewer_index
.status
));
1934 vstream
->index_sent_seqcount
++;
1938 * Indexes are stored in big endian, no need to switch before sending.
1940 DBG("Sending viewer index for stream %" PRIu64
" offset %" PRIu64
,
1941 rstream
->stream_handle
,
1942 (uint64_t) be64toh(packet_index
.offset
));
1943 viewer_index
.offset
= packet_index
.offset
;
1944 viewer_index
.packet_size
= packet_index
.packet_size
;
1945 viewer_index
.content_size
= packet_index
.content_size
;
1946 viewer_index
.timestamp_begin
= packet_index
.timestamp_begin
;
1947 viewer_index
.timestamp_end
= packet_index
.timestamp_end
;
1948 viewer_index
.events_discarded
= packet_index
.events_discarded
;
1949 viewer_index
.stream_id
= packet_index
.stream_id
;
1953 pthread_mutex_unlock(&rstream
->lock
);
1954 pthread_mutex_unlock(&rstream
->trace
->session
->lock
);
1957 if (metadata_viewer_stream
) {
1958 pthread_mutex_lock(&metadata_viewer_stream
->stream
->lock
);
1959 DBG("get next index metadata check: recv %" PRIu64
" sent %" PRIu64
,
1960 metadata_viewer_stream
->stream
->metadata_received
,
1961 metadata_viewer_stream
->metadata_sent
);
1962 if (!metadata_viewer_stream
->stream
->metadata_received
||
1963 metadata_viewer_stream
->stream
->metadata_received
>
1964 metadata_viewer_stream
->metadata_sent
) {
1965 viewer_index
.flags
|= LTTNG_VIEWER_FLAG_NEW_METADATA
;
1967 pthread_mutex_unlock(&metadata_viewer_stream
->stream
->lock
);
1970 if (attached_sessions_have_new_streams
) {
1971 viewer_index
.flags
|= LTTNG_VIEWER_FLAG_NEW_STREAM
;
1974 viewer_index
.flags
= htobe32(viewer_index
.flags
);
1975 viewer_index
.status
= htobe32(viewer_index
.status
);
1976 health_code_update();
1978 ret
= send_response(conn
->sock
, &viewer_index
, sizeof(viewer_index
));
1982 health_code_update();
1985 DBG("Index %" PRIu64
" for stream %" PRIu64
" sent",
1986 vstream
->index_sent_seqcount
,
1987 vstream
->stream
->stream_handle
);
1990 if (metadata_viewer_stream
) {
1991 viewer_stream_put(metadata_viewer_stream
);
1994 viewer_stream_put(vstream
);
1999 pthread_mutex_unlock(&rstream
->lock
);
2000 pthread_mutex_unlock(&rstream
->trace
->session
->lock
);
2001 if (metadata_viewer_stream
) {
2002 viewer_stream_put(metadata_viewer_stream
);
2004 viewer_stream_put(vstream
);
2009 * Send the next index for a stream
2011 * Return 0 on success or else a negative value.
2013 static int viewer_get_packet(struct relay_connection
*conn
)
2017 char *reply
= nullptr;
2018 struct lttng_viewer_get_packet get_packet_info
;
2019 struct lttng_viewer_trace_packet reply_header
;
2020 struct relay_viewer_stream
*vstream
= nullptr;
2021 uint32_t reply_size
= sizeof(reply_header
);
2022 uint32_t packet_data_len
= 0;
2025 enum lttng_viewer_get_packet_return_code get_packet_status
;
2027 health_code_update();
2029 ret
= recv_request(conn
->sock
, &get_packet_info
, sizeof(get_packet_info
));
2033 health_code_update();
2035 /* From this point on, the error label can be reached. */
2036 memset(&reply_header
, 0, sizeof(reply_header
));
2037 stream_id
= (uint64_t) be64toh(get_packet_info
.stream_id
);
2039 vstream
= viewer_stream_get_by_id(stream_id
);
2041 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2042 DBG("Client requested packet of unknown stream id %" PRIu64
", returning status=%s",
2044 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2045 goto send_reply_nolock
;
2047 packet_data_len
= be32toh(get_packet_info
.len
);
2048 reply_size
+= packet_data_len
;
2051 reply
= zmalloc
<char>(reply_size
);
2053 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2054 PERROR("Falled to allocate reply, returning status=%s",
2055 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2059 pthread_mutex_lock(&vstream
->stream
->lock
);
2060 lseek_ret
= fs_handle_seek(
2061 vstream
->stream_file
.handle
, be64toh(get_packet_info
.offset
), SEEK_SET
);
2062 if (lseek_ret
< 0) {
2063 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2064 PERROR("Failed to seek file system handle of viewer stream %" PRIu64
2065 " to offset %" PRIu64
", returning status=%s",
2067 (uint64_t) be64toh(get_packet_info
.offset
),
2068 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2071 read_len
= fs_handle_read(
2072 vstream
->stream_file
.handle
, reply
+ sizeof(reply_header
), packet_data_len
);
2073 if (read_len
< packet_data_len
) {
2074 get_packet_status
= LTTNG_VIEWER_GET_PACKET_ERR
;
2075 PERROR("Failed to read from file system handle of viewer stream id %" PRIu64
2076 ", offset: %" PRIu64
", returning status=%s",
2078 (uint64_t) be64toh(get_packet_info
.offset
),
2079 lttng_viewer_get_packet_return_code_str(get_packet_status
));
2083 get_packet_status
= LTTNG_VIEWER_GET_PACKET_OK
;
2084 reply_header
.len
= htobe32(packet_data_len
);
2088 /* No payload to send on error. */
2089 reply_size
= sizeof(reply_header
);
2093 pthread_mutex_unlock(&vstream
->stream
->lock
);
2097 health_code_update();
2099 reply_header
.status
= htobe32(get_packet_status
);
2101 memcpy(reply
, &reply_header
, sizeof(reply_header
));
2102 ret
= send_response(conn
->sock
, reply
, reply_size
);
2104 /* No reply to send. */
2105 ret
= send_response(conn
->sock
, &reply_header
, reply_size
);
2108 health_code_update();
2110 PERROR("sendmsg of packet data failed");
2114 DBG("Sent %u bytes for stream %" PRIu64
, reply_size
, stream_id
);
2120 viewer_stream_put(vstream
);
2126 * Send the session's metadata
2128 * Return 0 on success else a negative value.
2130 static int viewer_get_metadata(struct relay_connection
*conn
)
2136 char *data
= nullptr;
2137 struct lttng_viewer_get_metadata request
;
2138 struct lttng_viewer_metadata_packet reply
;
2139 struct relay_viewer_stream
*vstream
= nullptr;
2140 bool dispose_of_stream
= false;
2144 health_code_update();
2146 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
2150 health_code_update();
2152 memset(&reply
, 0, sizeof(reply
));
2154 vstream
= viewer_stream_get_by_id(be64toh(request
.stream_id
));
2157 * The metadata stream can be closed by a CLOSE command
2158 * just before we attach. It can also be closed by
2159 * per-pid tracing during tracing. Therefore, it is
2160 * possible that we cannot find this viewer stream.
2161 * Reply back to the client with an error if we cannot
2164 DBG("Client requested metadata of unknown stream id %" PRIu64
,
2165 (uint64_t) be64toh(request
.stream_id
));
2166 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2170 pthread_mutex_lock(&vstream
->stream
->trace
->session
->lock
);
2171 pthread_mutex_lock(&vstream
->stream
->trace
->lock
);
2172 pthread_mutex_lock(&vstream
->stream
->lock
);
2173 if (!vstream
->stream
->is_metadata
) {
2174 ERR("Invalid metadata stream");
2178 if (vstream
->metadata_sent
>= vstream
->stream
->metadata_received
) {
2180 * Clear feature resets the metadata_received to 0 until the
2181 * same metadata is received again.
2183 reply
.status
= htobe32(LTTNG_VIEWER_NO_NEW_METADATA
);
2185 * The live viewer considers a closed 0 byte metadata stream as
2188 dispose_of_stream
= vstream
->metadata_sent
> 0 && vstream
->stream
->closed
;
2192 if (vstream
->stream
->trace_chunk
&&
2193 !lttng_trace_chunk_ids_equal(conn
->viewer_session
->current_trace_chunk
,
2194 vstream
->stream
->trace_chunk
)) {
2195 /* A rotation has occurred on the relay stream. */
2196 DBG("Metadata relay stream and viewer chunk ids differ");
2198 ret
= viewer_session_set_trace_chunk_copy(conn
->viewer_session
,
2199 vstream
->stream
->trace_chunk
);
2201 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2206 if (conn
->viewer_session
->current_trace_chunk
&&
2207 !lttng_trace_chunk_ids_equal(conn
->viewer_session
->current_trace_chunk
,
2208 vstream
->stream_file
.trace_chunk
)) {
2209 bool acquired_reference
;
2211 DBG("Viewer session and viewer stream chunk differ: "
2212 "vsession chunk %p vstream chunk %p",
2213 conn
->viewer_session
->current_trace_chunk
,
2214 vstream
->stream_file
.trace_chunk
);
2215 lttng_trace_chunk_put(vstream
->stream_file
.trace_chunk
);
2216 acquired_reference
=
2217 lttng_trace_chunk_get(conn
->viewer_session
->current_trace_chunk
);
2218 LTTNG_ASSERT(acquired_reference
);
2219 vstream
->stream_file
.trace_chunk
= conn
->viewer_session
->current_trace_chunk
;
2220 viewer_stream_close_files(vstream
);
2223 len
= vstream
->stream
->metadata_received
- vstream
->metadata_sent
;
2225 if (!vstream
->stream_file
.trace_chunk
) {
2226 if (vstream
->stream
->trace
->session
->connection_closed
) {
2228 * If the connection is closed, there is no way for the metadata stream
2229 * to ever transition back to an active chunk. As such, signal to the viewer
2230 * that there is no new metadata available.
2232 * The stream can be disposed-of. On the next execution of this command,
2233 * the relay daemon will reply with an error status since the stream can't
2236 dispose_of_stream
= true;
2239 reply
.status
= htobe32(LTTNG_VIEWER_NO_NEW_METADATA
);
2242 } else if (vstream
->stream_file
.trace_chunk
&& !vstream
->stream_file
.handle
&& len
> 0) {
2244 * Either this is the first time the metadata file is read, or a
2245 * rotation of the corresponding relay stream has occurred.
2247 struct fs_handle
*fs_handle
;
2248 char file_path
[LTTNG_PATH_MAX
];
2249 enum lttng_trace_chunk_status status
;
2250 struct relay_stream
*rstream
= vstream
->stream
;
2252 ret
= utils_stream_file_path(rstream
->path_name
,
2253 rstream
->channel_name
,
2254 rstream
->tracefile_size
,
2255 vstream
->current_tracefile_id
,
2264 * It is possible the the metadata file we are trying to open is
2265 * missing if the stream has been closed (application exits with
2266 * per-pid buffers) and a clear command has been performed.
2268 status
= lttng_trace_chunk_open_fs_handle(
2269 vstream
->stream_file
.trace_chunk
, file_path
, O_RDONLY
, 0, &fs_handle
, true);
2270 if (status
!= LTTNG_TRACE_CHUNK_STATUS_OK
) {
2271 if (status
== LTTNG_TRACE_CHUNK_STATUS_NO_FILE
) {
2272 reply
.status
= htobe32(LTTNG_VIEWER_NO_NEW_METADATA
);
2274 if (vstream
->stream
->closed
) {
2275 viewer_stream_put(vstream
);
2279 PERROR("Failed to open metadata file for viewer stream");
2282 vstream
->stream_file
.handle
= fs_handle
;
2284 if (vstream
->metadata_sent
!= 0) {
2286 * The client does not expect to receive any metadata
2287 * it has received and metadata files in successive
2288 * chunks must be a strict superset of one another.
2290 * Skip the first `metadata_sent` bytes to ensure
2291 * they are not sent a second time to the client.
2293 * Baring a block layer error or an internal error,
2294 * this seek should not fail as
2295 * `vstream->stream->metadata_received` is reset when
2296 * a relay stream is rotated. If this is reached, it is
2297 * safe to assume that
2298 * `metadata_received` > `metadata_sent`.
2300 const off_t seek_ret
=
2301 fs_handle_seek(fs_handle
, vstream
->metadata_sent
, SEEK_SET
);
2304 PERROR("Failed to seek metadata viewer stream file to `sent` position: pos = %" PRId64
,
2305 vstream
->metadata_sent
);
2306 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2312 reply
.len
= htobe64(len
);
2313 data
= zmalloc
<char>(len
);
2315 PERROR("viewer metadata zmalloc");
2319 fd
= fs_handle_get_fd(vstream
->stream_file
.handle
);
2321 ERR("Failed to restore viewer stream file system handle");
2324 read_len
= lttng_read(fd
, data
, len
);
2325 fs_handle_put_fd(vstream
->stream_file
.handle
);
2327 if (read_len
< len
) {
2329 PERROR("Failed to read metadata file");
2333 * A clear has been performed which prevents the relay
2334 * from sending `len` bytes of metadata.
2336 * It is important not to send any metadata if we
2337 * couldn't read all the available metadata in one shot:
2338 * sending partial metadata can cause the client to
2339 * attempt to parse an incomplete (incoherent) metadata
2340 * stream, which would result in an error.
2342 const off_t seek_ret
=
2343 fs_handle_seek(vstream
->stream_file
.handle
, -read_len
, SEEK_CUR
);
2345 DBG("Failed to read metadata: requested = %" PRIu64
", got = %zd",
2351 PERROR("Failed to restore metadata file position after partial read");
2357 vstream
->metadata_sent
+= read_len
;
2358 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_OK
);
2363 reply
.status
= htobe32(LTTNG_VIEWER_METADATA_ERR
);
2366 health_code_update();
2368 pthread_mutex_unlock(&vstream
->stream
->lock
);
2369 pthread_mutex_unlock(&vstream
->stream
->trace
->lock
);
2370 pthread_mutex_unlock(&vstream
->stream
->trace
->session
->lock
);
2372 ret
= send_response(conn
->sock
, &reply
, sizeof(reply
));
2376 health_code_update();
2379 ret
= send_response(conn
->sock
, data
, len
);
2385 DBG("Sent %" PRIu64
" bytes of metadata for stream %" PRIu64
,
2387 (uint64_t) be64toh(request
.stream_id
));
2389 DBG("Metadata sent");
2395 viewer_stream_put(vstream
);
2396 if (dispose_of_stream
) {
2398 * Trigger the destruction of the viewer stream
2399 * by releasing its global reference.
2401 * The live viewers expect to receive a NO_NEW_METADATA
2402 * status before a stream disappears, otherwise they abort the
2403 * entire live connection when receiving an error status.
2405 * On the next query for this stream, an error will be reported to the
2408 viewer_stream_put(vstream
);
2416 * Create a viewer session.
2418 * Return 0 on success or else a negative value.
2420 static int viewer_create_session(struct relay_connection
*conn
)
2423 struct lttng_viewer_create_session_response resp
;
2425 memset(&resp
, 0, sizeof(resp
));
2426 resp
.status
= htobe32(LTTNG_VIEWER_CREATE_SESSION_OK
);
2427 conn
->viewer_session
= viewer_session_create();
2428 if (!conn
->viewer_session
) {
2429 ERR("Allocation viewer session");
2430 resp
.status
= htobe32(LTTNG_VIEWER_CREATE_SESSION_ERR
);
2435 health_code_update();
2436 ret
= send_response(conn
->sock
, &resp
, sizeof(resp
));
2440 health_code_update();
2448 * Detach a viewer session.
2450 * Return 0 on success or else a negative value.
2452 static int viewer_detach_session(struct relay_connection
*conn
)
2455 struct lttng_viewer_detach_session_response response
;
2456 struct lttng_viewer_detach_session_request request
;
2457 struct relay_session
*session
= nullptr;
2458 uint64_t viewer_session_to_close
;
2462 health_code_update();
2464 /* Receive the request from the connected client. */
2465 ret
= recv_request(conn
->sock
, &request
, sizeof(request
));
2469 viewer_session_to_close
= be64toh(request
.session_id
);
2471 if (!conn
->viewer_session
) {
2472 DBG("Client trying to detach before creating a live viewer session");
2473 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR
);
2477 health_code_update();
2479 memset(&response
, 0, sizeof(response
));
2480 DBG("Detaching from session ID %" PRIu64
, viewer_session_to_close
);
2482 session
= session_get_by_id(be64toh(request
.session_id
));
2484 DBG("Relay session %" PRIu64
" not found", (uint64_t) be64toh(request
.session_id
));
2485 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_UNK
);
2489 ret
= viewer_session_is_attached(conn
->viewer_session
, session
);
2491 DBG("Not attached to this session");
2492 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_ERR
);
2493 goto send_reply_put
;
2496 viewer_session_close_one_session(conn
->viewer_session
, session
);
2497 response
.status
= htobe32(LTTNG_VIEWER_DETACH_SESSION_OK
);
2498 DBG("Session %" PRIu64
" detached.", viewer_session_to_close
);
2501 session_put(session
);
2504 health_code_update();
2505 ret
= send_response(conn
->sock
, &response
, sizeof(response
));
2509 health_code_update();
2517 * live_relay_unknown_command: send -1 if received unknown command
2519 static void live_relay_unknown_command(struct relay_connection
*conn
)
2521 struct lttcomm_relayd_generic_reply reply
;
2523 memset(&reply
, 0, sizeof(reply
));
2524 reply
.ret_code
= htobe32(LTTNG_ERR_UNK
);
2525 (void) send_response(conn
->sock
, &reply
, sizeof(reply
));
2529 * Process the commands received on the control socket
2531 static int process_control(struct lttng_viewer_cmd
*recv_hdr
, struct relay_connection
*conn
)
2534 lttng_viewer_command cmd
= (lttng_viewer_command
) be32toh(recv_hdr
->cmd
);
2537 * Make sure we've done the version check before any command other then
2538 * a new client connection.
2540 if (cmd
!= LTTNG_VIEWER_CONNECT
&& !conn
->version_check_done
) {
2541 ERR("Viewer on connection %d requested %s command before version check",
2543 lttng_viewer_command_str(cmd
));
2548 DBG("Processing %s viewer command from connection %d",
2549 lttng_viewer_command_str(cmd
),
2553 case LTTNG_VIEWER_CONNECT
:
2554 ret
= viewer_connect(conn
);
2556 case LTTNG_VIEWER_LIST_SESSIONS
:
2557 ret
= viewer_list_sessions(conn
);
2559 case LTTNG_VIEWER_ATTACH_SESSION
:
2560 ret
= viewer_attach_session(conn
);
2562 case LTTNG_VIEWER_GET_NEXT_INDEX
:
2563 ret
= viewer_get_next_index(conn
);
2565 case LTTNG_VIEWER_GET_PACKET
:
2566 ret
= viewer_get_packet(conn
);
2568 case LTTNG_VIEWER_GET_METADATA
:
2569 ret
= viewer_get_metadata(conn
);
2571 case LTTNG_VIEWER_GET_NEW_STREAMS
:
2572 ret
= viewer_get_new_streams(conn
);
2574 case LTTNG_VIEWER_CREATE_SESSION
:
2575 ret
= viewer_create_session(conn
);
2577 case LTTNG_VIEWER_DETACH_SESSION
:
2578 ret
= viewer_detach_session(conn
);
2581 ERR("Received unknown viewer command (%u)", be32toh(recv_hdr
->cmd
));
2582 live_relay_unknown_command(conn
);
2591 static void cleanup_connection_pollfd(struct lttng_poll_event
*events
, int pollfd
)
2595 (void) lttng_poll_del(events
, pollfd
);
2597 ret
= fd_tracker_close_unsuspendable_fd(
2598 the_fd_tracker
, &pollfd
, 1, fd_tracker_util_close_fd
, nullptr);
2600 ERR("Closing pollfd %d", pollfd
);
2605 * This thread does the actual work
2607 static void *thread_worker(void *data
__attribute__((unused
)))
2611 struct lttng_poll_event events
;
2612 struct lttng_ht
*viewer_connections_ht
;
2613 struct lttng_ht_iter iter
;
2614 struct lttng_viewer_cmd recv_hdr
;
2615 struct relay_connection
*destroy_conn
;
2617 DBG("[thread] Live viewer relay worker started");
2619 rcu_register_thread();
2621 health_register(health_relayd
, HEALTH_RELAYD_TYPE_LIVE_WORKER
);
2623 if (testpoint(relayd_thread_live_worker
)) {
2624 goto error_testpoint
;
2627 /* table of connections indexed on socket */
2628 viewer_connections_ht
= lttng_ht_new(0, LTTNG_HT_TYPE_ULONG
);
2629 if (!viewer_connections_ht
) {
2630 goto viewer_connections_ht_error
;
2633 ret
= create_named_thread_poll_set(&events
, 2, "Live viewer worker thread epoll");
2635 goto error_poll_create
;
2638 ret
= lttng_poll_add(&events
, live_conn_pipe
[0], LPOLLIN
| LPOLLRDHUP
);
2647 health_code_update();
2649 /* Infinite blocking call, waiting for transmission */
2650 DBG3("Relayd live viewer worker thread polling...");
2651 health_poll_entry();
2652 ret
= lttng_poll_wait(&events
, -1);
2656 * Restart interrupted system call.
2658 if (errno
== EINTR
) {
2667 * Process control. The control connection is prioritised so we don't
2668 * starve it with high throughput tracing data on the data
2671 for (i
= 0; i
< nb_fd
; i
++) {
2672 /* Fetch once the poll data */
2673 const auto revents
= LTTNG_POLL_GETEV(&events
, i
);
2674 const auto pollfd
= LTTNG_POLL_GETFD(&events
, i
);
2676 health_code_update();
2678 /* Activity on thread quit pipe, exiting. */
2679 if (relayd_is_thread_quit_pipe(pollfd
)) {
2680 DBG("Activity on thread quit pipe");
2685 /* Inspect the relay conn pipe for new connection. */
2686 if (pollfd
== live_conn_pipe
[0]) {
2687 if (revents
& LPOLLIN
) {
2688 struct relay_connection
*conn
;
2690 ret
= lttng_read(live_conn_pipe
[0],
2692 sizeof(conn
)); /* NOLINT sizeof used on a
2697 ret
= lttng_poll_add(
2698 &events
, conn
->sock
->fd
, LPOLLIN
| LPOLLRDHUP
);
2700 ERR("Failed to add new live connection file descriptor to poll set");
2703 connection_ht_add(viewer_connections_ht
, conn
);
2704 DBG("Connection socket %d added to poll", conn
->sock
->fd
);
2705 } else if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2706 ERR("Relay live pipe error");
2709 ERR("Unexpected poll events %u for sock %d",
2715 /* Connection activity. */
2716 struct relay_connection
*conn
;
2718 conn
= connection_get_by_sock(viewer_connections_ht
, pollfd
);
2723 if (revents
& LPOLLIN
) {
2724 ret
= conn
->sock
->ops
->recvmsg(
2725 conn
->sock
, &recv_hdr
, sizeof(recv_hdr
), 0);
2727 /* Connection closed. */
2728 cleanup_connection_pollfd(&events
, pollfd
);
2729 /* Put "create" ownership reference. */
2730 connection_put(conn
);
2731 DBG("Viewer control conn closed with %d", pollfd
);
2733 ret
= process_control(&recv_hdr
, conn
);
2735 /* Clear the session on error. */
2736 cleanup_connection_pollfd(&events
, pollfd
);
2737 /* Put "create" ownership reference. */
2738 connection_put(conn
);
2739 DBG("Viewer connection closed with %d",
2743 } else if (revents
& (LPOLLERR
| LPOLLHUP
| LPOLLRDHUP
)) {
2744 cleanup_connection_pollfd(&events
, pollfd
);
2745 /* Put "create" ownership reference. */
2746 connection_put(conn
);
2748 ERR("Unexpected poll events %u for sock %d",
2751 connection_put(conn
);
2754 /* Put local "get_by_sock" reference. */
2755 connection_put(conn
);
2762 (void) fd_tracker_util_poll_clean(the_fd_tracker
, &events
);
2764 /* Cleanup remaining connection object. */
2766 lttng::urcu::read_lock_guard read_lock
;
2768 cds_lfht_for_each_entry (
2769 viewer_connections_ht
->ht
, &iter
.iter
, destroy_conn
, sock_n
.node
) {
2770 health_code_update();
2771 connection_put(destroy_conn
);
2775 lttng_ht_destroy(viewer_connections_ht
);
2776 viewer_connections_ht_error
:
2777 /* Close relay conn pipes */
2778 (void) fd_tracker_util_pipe_close(the_fd_tracker
, live_conn_pipe
);
2780 DBG("Viewer worker thread exited with error");
2782 DBG("Viewer worker thread cleanup complete");
2786 ERR("Health error occurred in %s", __func__
);
2788 health_unregister(health_relayd
);
2789 if (lttng_relay_stop_threads()) {
2790 ERR("Error stopping threads");
2792 rcu_unregister_thread();
2797 * Create the relay command pipe to wake thread_manage_apps.
2798 * Closed in cleanup().
2800 static int create_conn_pipe()
2802 return fd_tracker_util_pipe_open_cloexec(
2803 the_fd_tracker
, "Live connection pipe", live_conn_pipe
);
2806 int relayd_live_join()
2808 int ret
, retval
= 0;
2811 ret
= pthread_join(live_listener_thread
, &status
);
2814 PERROR("pthread_join live listener");
2818 ret
= pthread_join(live_worker_thread
, &status
);
2821 PERROR("pthread_join live worker");
2825 ret
= pthread_join(live_dispatcher_thread
, &status
);
2828 PERROR("pthread_join live dispatcher");
2832 cleanup_relayd_live();
2840 int relayd_live_create(struct lttng_uri
*uri
)
2842 int ret
= 0, retval
= 0;
2848 goto exit_init_data
;
2852 /* Check if daemon is UID = 0 */
2853 is_root
= !getuid();
2856 if (live_uri
->port
< 1024) {
2857 ERR("Need to be root to use ports < 1024");
2859 goto exit_init_data
;
2863 /* Setup the thread apps communication pipe. */
2864 if (create_conn_pipe()) {
2866 goto exit_init_data
;
2869 /* Init relay command queue. */
2870 cds_wfcq_init(&viewer_conn_queue
.head
, &viewer_conn_queue
.tail
);
2872 /* Set up max poll set size */
2873 if (lttng_poll_set_max_size()) {
2875 goto exit_init_data
;
2878 /* Setup the dispatcher thread */
2879 ret
= pthread_create(&live_dispatcher_thread
,
2880 default_pthread_attr(),
2885 PERROR("pthread_create viewer dispatcher");
2887 goto exit_dispatcher_thread
;
2890 /* Setup the worker thread */
2891 ret
= pthread_create(&live_worker_thread
, default_pthread_attr(), thread_worker
, nullptr);
2894 PERROR("pthread_create viewer worker");
2896 goto exit_worker_thread
;
2899 /* Setup the listener thread */
2900 ret
= pthread_create(
2901 &live_listener_thread
, default_pthread_attr(), thread_listener
, (void *) nullptr);
2904 PERROR("pthread_create viewer listener");
2906 goto exit_listener_thread
;
2910 * All OK, started all threads.
2915 * Join on the live_listener_thread should anything be added after
2916 * the live_listener thread's creation.
2919 exit_listener_thread
:
2921 ret
= pthread_join(live_worker_thread
, &status
);
2924 PERROR("pthread_join live worker");
2929 ret
= pthread_join(live_dispatcher_thread
, &status
);
2932 PERROR("pthread_join live dispatcher");
2935 exit_dispatcher_thread
:
2938 cleanup_relayd_live();