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
11 #include <common/common.h>
12 #include <urcu/rculist.h>
14 #include "lttng-relayd.h"
15 #include "ctf-trace.h"
17 #include "viewer-session.h"
18 #include "viewer-stream.h"
21 struct relay_viewer_session
*viewer_session_create(void)
23 struct relay_viewer_session
*vsession
;
25 vsession
= zmalloc(sizeof(*vsession
));
29 CDS_INIT_LIST_HEAD(&vsession
->session_list
);
34 int viewer_session_set_trace_chunk_copy(struct relay_viewer_session
*vsession
,
35 struct lttng_trace_chunk
*relay_session_trace_chunk
)
38 struct lttng_trace_chunk
*viewer_chunk
;
40 assert(relay_session_trace_chunk
);
41 lttng_trace_chunk_put(vsession
->current_trace_chunk
);
42 vsession
->current_trace_chunk
= NULL
;
44 DBG("Copying relay session's current trace chunk to the viewer session");
45 viewer_chunk
= lttng_trace_chunk_copy(relay_session_trace_chunk
);
47 ERR("Failed to create a viewer trace chunk from the relay session's current chunk");
52 vsession
->current_trace_chunk
= viewer_chunk
;
57 /* The existence of session must be guaranteed by the caller. */
58 enum lttng_viewer_attach_return_code
viewer_session_attach(
59 struct relay_viewer_session
*vsession
,
60 struct relay_session
*session
)
62 enum lttng_viewer_attach_return_code viewer_attach_status
=
63 LTTNG_VIEWER_ATTACH_OK
;
65 ASSERT_LOCKED(session
->lock
);
67 /* Will not fail, as per the ownership guarantee. */
68 if (!session_get(session
)) {
69 viewer_attach_status
= LTTNG_VIEWER_ATTACH_UNK
;
72 if (session
->viewer_attached
) {
73 viewer_attach_status
= LTTNG_VIEWER_ATTACH_ALREADY
;
77 assert(session
->current_trace_chunk
);
78 assert(!vsession
->current_trace_chunk
);
79 session
->viewer_attached
= true;
81 ret
= viewer_session_set_trace_chunk_copy(vsession
,
82 session
->current_trace_chunk
);
85 * The live protocol does not define a generic error
86 * value for the "attach" command. The "unknown"
87 * status is used so that the viewer may handle this
88 * failure as if the session didn't exist anymore.
90 DBG("Failed to create a viewer trace chunk from the current trace chunk of session \"%s\", returning LTTNG_VIEWER_ATTACH_UNK",
91 session
->session_name
);
92 viewer_attach_status
= LTTNG_VIEWER_ATTACH_UNK
;
96 if (viewer_attach_status
== LTTNG_VIEWER_ATTACH_OK
) {
97 pthread_mutex_lock(&vsession
->session_list_lock
);
98 /* Ownership is transfered to the list. */
99 cds_list_add_rcu(&session
->viewer_session_node
,
100 &vsession
->session_list
);
101 pthread_mutex_unlock(&vsession
->session_list_lock
);
103 /* Put our local ref. */
104 session_put(session
);
107 return viewer_attach_status
;
110 /* The existence of session must be guaranteed by the caller. */
111 static int viewer_session_detach(struct relay_viewer_session
*vsession
,
112 struct relay_session
*session
)
116 pthread_mutex_lock(&session
->lock
);
117 if (!session
->viewer_attached
) {
120 session
->viewer_attached
= false;
124 pthread_mutex_lock(&vsession
->session_list_lock
);
125 cds_list_del_rcu(&session
->viewer_session_node
);
126 pthread_mutex_unlock(&vsession
->session_list_lock
);
127 /* Release reference held by the list. */
128 session_put(session
);
130 /* Safe since we know the session exists. */
131 pthread_mutex_unlock(&session
->lock
);
135 void viewer_session_destroy(struct relay_viewer_session
*vsession
)
137 lttng_trace_chunk_put(vsession
->current_trace_chunk
);
142 * Release ownership of all the streams of one session and detach the viewer.
144 void viewer_session_close_one_session(struct relay_viewer_session
*vsession
,
145 struct relay_session
*session
)
147 struct lttng_ht_iter iter
;
148 struct relay_viewer_stream
*vstream
;
151 * TODO: improvement: create more efficient list of
152 * vstream per session.
154 cds_lfht_for_each_entry(viewer_streams_ht
->ht
, &iter
.iter
,
155 vstream
, stream_n
.node
) {
156 if (!viewer_stream_get(vstream
)) {
159 if (vstream
->stream
->trace
->session
!= session
) {
160 viewer_stream_put(vstream
);
163 /* Put local reference. */
164 viewer_stream_put(vstream
);
166 * We have reached one of the viewer stream's lifetime
167 * end condition. This "put" will cause the proper
168 * teardown of the viewer stream.
170 viewer_stream_put(vstream
);
172 lttng_trace_chunk_put(vsession
->current_trace_chunk
);
173 vsession
->current_trace_chunk
= NULL
;
174 viewer_session_detach(vsession
, session
);
177 void viewer_session_close(struct relay_viewer_session
*vsession
)
179 struct relay_session
*session
;
182 cds_list_for_each_entry_rcu(session
,
183 &vsession
->session_list
, viewer_session_node
) {
184 viewer_session_close_one_session(vsession
, session
);
190 * Check if a connection is attached to a session.
191 * Return 1 if attached, 0 if not attached, a negative value on error.
193 int viewer_session_is_attached(struct relay_viewer_session
*vsession
,
194 struct relay_session
*session
)
196 struct relay_session
*iter
;
199 pthread_mutex_lock(&session
->lock
);
203 if (!session
->viewer_attached
) {
207 cds_list_for_each_entry_rcu(iter
,
208 &vsession
->session_list
,
209 viewer_session_node
) {
210 if (session
== iter
) {
218 pthread_mutex_unlock(&session
->lock
);