2 * Copyright (C) 2013 - Julien Desfossez <jdesfossez@efficios.com>
3 * David Goulet <dgoulet@efficios.com>
4 * 2015 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License, version 2 only, as
8 * published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc., 51
17 * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
24 #include <common/common.h>
25 #include <common/utils.h>
26 #include <urcu/rculist.h>
28 #include "ctf-trace.h"
29 #include "lttng-relayd.h"
32 static uint64_t last_relay_ctf_trace_id
;
33 static pthread_mutex_t last_relay_ctf_trace_id_lock
= PTHREAD_MUTEX_INITIALIZER
;
35 static void rcu_destroy_ctf_trace(struct rcu_head
*rcu_head
)
37 struct ctf_trace
*trace
=
38 caa_container_of(rcu_head
, struct ctf_trace
, rcu_node
);
44 * Destroy a ctf trace and all stream contained in it.
46 * MUST be called with the RCU read side lock.
48 void ctf_trace_destroy(struct ctf_trace
*trace
)
51 * Getting to this point, every stream referenced by that trace
52 * have put back their ref since the've been closed by the
55 assert(cds_list_empty(&trace
->stream_list
));
56 session_put(trace
->session
);
57 trace
->session
= NULL
;
58 call_rcu(&trace
->rcu_node
, rcu_destroy_ctf_trace
);
61 void ctf_trace_release(struct urcu_ref
*ref
)
63 struct ctf_trace
*trace
=
64 caa_container_of(ref
, struct ctf_trace
, ref
);
66 struct lttng_ht_iter iter
;
68 iter
.iter
.node
= &trace
->node
.node
;
69 ret
= lttng_ht_del(trace
->session
->ctf_traces_ht
, &iter
);
71 ctf_trace_destroy(trace
);
75 * Should be called with RCU read-side lock held.
77 bool ctf_trace_get(struct ctf_trace
*trace
)
81 /* Confirm that the trace refcount has not reached 0. */
82 pthread_mutex_lock(&trace
->reflock
);
83 if (trace
->ref
.refcount
!= 0) {
85 urcu_ref_get(&trace
->ref
);
87 pthread_mutex_unlock(&trace
->reflock
);
93 * Create and return an allocated ctf_trace. NULL on error.
94 * There is no "open" and "close" for a ctf_trace, but rather just a
95 * create and refcounting. Whenever all the streams belonging to a trace
96 * put their reference, its refcount drops to 0.
98 static struct ctf_trace
*ctf_trace_create(struct relay_session
*session
,
101 struct ctf_trace
*trace
;
103 trace
= zmalloc(sizeof(*trace
));
105 PERROR("ctf_trace alloc");
109 if (!session_get(session
)) {
110 ERR("Cannot get session");
115 trace
->session
= session
;
117 CDS_INIT_LIST_HEAD(&trace
->stream_list
);
119 pthread_mutex_lock(&last_relay_ctf_trace_id_lock
);
120 trace
->id
= ++last_relay_ctf_trace_id
;
121 pthread_mutex_unlock(&last_relay_ctf_trace_id_lock
);
123 lttng_ht_node_init_str(&trace
->node
, path_name
);
124 trace
->session
= session
;
125 urcu_ref_init(&trace
->ref
);
126 pthread_mutex_init(&trace
->lock
, NULL
);
127 pthread_mutex_init(&trace
->reflock
, NULL
);
128 pthread_mutex_init(&trace
->stream_list_lock
, NULL
);
129 lttng_ht_add_str(session
->ctf_traces_ht
, &trace
->node
);
131 DBG("Created ctf_trace %" PRIu64
" with path: %s", trace
->id
, path_name
);
138 * Return a ctf_trace if found by id in the given hash table else NULL.
139 * Hold a reference on the ctf_trace, and must be paired with
142 struct ctf_trace
*ctf_trace_get_by_path_or_create(struct relay_session
*session
,
145 struct lttng_ht_node_str
*node
;
146 struct lttng_ht_iter iter
;
147 struct ctf_trace
*trace
= NULL
;
150 lttng_ht_lookup(session
->ctf_traces_ht
, (void *) path_name
, &iter
);
151 node
= lttng_ht_iter_get_node_str(&iter
);
153 DBG("CTF Trace path %s not found", path_name
);
156 trace
= caa_container_of(node
, struct ctf_trace
, node
);
157 if (!ctf_trace_get(trace
)) {
164 trace
= ctf_trace_create(session
, path_name
);
169 void ctf_trace_put(struct ctf_trace
*trace
)
172 pthread_mutex_lock(&trace
->reflock
);
173 urcu_ref_put(&trace
->ref
, ctf_trace_release
);
174 pthread_mutex_unlock(&trace
->reflock
);
178 int ctf_trace_close(struct ctf_trace
*trace
)
180 struct relay_stream
*stream
;
183 cds_list_for_each_entry_rcu(stream
, &trace
->stream_list
,
186 * Close stream since the connection owning the trace is being
189 try_stream_close(stream
);
193 * Since all references to the trace are held by its streams, we
194 * don't need to do any self-ref put.
199 struct relay_viewer_stream
*ctf_trace_get_viewer_metadata_stream(struct ctf_trace
*trace
)
201 struct relay_viewer_stream
*vstream
;
204 vstream
= rcu_dereference(trace
->viewer_metadata_stream
);
208 if (!viewer_stream_get(vstream
)) {