X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-relayd%2Fmain.c;h=7e5733ec8c3253432bd61dbac17b0968fefef21a;hp=b46c1628079b05619f564cbfe9f45969674d9a59;hb=a4baae1b0463bc4ce65c2a458c4a941e7fabc594;hpb=8966b2b03f62a03e132f504853e9699152e9399b

diff --git a/src/bin/lttng-relayd/main.c b/src/bin/lttng-relayd/main.c
index b46c16280..7e5733ec8 100644
--- a/src/bin/lttng-relayd/main.c
+++ b/src/bin/lttng-relayd/main.c
@@ -1147,6 +1147,70 @@ error:
 	return ret;
 }
 
+/*
+ * When we have received all the streams and the metadata for a channel,
+ * we make them visible to the viewer threads.
+ */
+static
+void set_viewer_ready_flag(struct relay_command *cmd)
+{
+	struct relay_stream_recv_handle *node, *tmp_node;
+
+	cds_list_for_each_entry_safe(node, tmp_node, &cmd->recv_head, node) {
+		struct relay_stream *stream;
+
+		rcu_read_lock();
+		stream = relay_stream_find_by_id(node->id);
+		if (!stream) {
+			/*
+			 * Stream is most probably being cleaned up by the data thread thus
+			 * simply continue to the next one.
+			 */
+			continue;
+		}
+
+		/*
+		 * If any of the streams in the list doesn't have a ctf_trace assigned,
+		 * it means that we never received the metadata stream, so we have to
+		 * wait until it arrives to make the streams available to the viewer.
+		 */
+		if (!stream->ctf_trace) {
+			goto end;
+		}
+
+		stream->viewer_ready = 1;
+		rcu_read_unlock();
+
+		/* Clean stream handle node. */
+		cds_list_del(&node->node);
+		free(node);
+	}
+
+end:
+	return;
+}
+
+/*
+ * Add a recv handle node to the connection recv list with the given stream
+ * handle. A new node is allocated thus must be freed when the node is deleted
+ * from the list.
+ */
+static void queue_stream_handle(uint64_t handle, struct relay_command *cmd)
+{
+	struct relay_stream_recv_handle *node;
+
+	assert(cmd);
+
+	node = zmalloc(sizeof(*node));
+	if (!node) {
+		PERROR("zmalloc queue stream handle");
+		return;
+	}
+
+	node->id = handle;
+	cds_list_add(&node->node, &cmd->recv_head);
+}
+
 /*
  * relay_add_stream: allocate a new stream for a session
  */
@@ -1239,6 +1303,13 @@ int relay_add_stream(struct lttcomm_relayd_hdr *recv_hdr,
 	ctf_trace_assign(cmd->ctf_traces_ht, stream);
 	stream->ctf_traces_ht = cmd->ctf_traces_ht;
 
+	/*
+	 * Add the stream handle in the recv list of the connection. Once the end
+	 * stream message is received, this list is emptied and streams are set
+	 * with the viewer ready flag.
+	 */
+	queue_stream_handle(stream->stream_handle, cmd);
+
 	lttng_ht_node_init_ulong(&stream->stream_n,
 			(unsigned long) stream->stream_handle);
 	lttng_ht_add_unique_ulong(relay_streams_ht,
@@ -1987,6 +2058,48 @@ end_no_session:
 	return ret;
 }
 
+/*
+ * Receive the streams_sent message.
+ *
+ * Return 0 on success else a negative value.
+ */
+static
+int relay_streams_sent(struct lttcomm_relayd_hdr *recv_hdr,
+		struct relay_command *cmd)
+{
+	int ret, send_ret;
+	struct lttcomm_relayd_generic_reply reply;
+
+	assert(cmd);
+
+	DBG("Relay receiving streams_sent");
+
+	if (!cmd->session || cmd->version_check_done == 0) {
+		ERR("Trying to close a stream before version check");
+		ret = -1;
+		goto end_no_session;
+	}
+
+	/*
+	 * Flag every pending stream in the connection recv list that they are
+	 * ready to be used by the viewer.
+	 */
+	set_viewer_ready_flag(cmd);
+
+	reply.ret_code = htobe32(LTTNG_OK);
+	send_ret = cmd->sock->ops->sendmsg(cmd->sock, &reply, sizeof(reply), 0);
+	if (send_ret < 0) {
+		ERR("Relay sending sent_stream reply");
+		ret = send_ret;
+	} else {
+		/* Success. */
+		ret = 0;
+	}
+
+end_no_session:
+	return ret;
+}
+
 /*
  * Process the commands received on the control socket
  */
@@ -2030,6 +2143,9 @@ int relay_process_control(struct lttcomm_relayd_hdr *recv_hdr,
 	case RELAYD_SEND_INDEX:
 		ret = relay_recv_index(recv_hdr, cmd);
 		break;
+	case RELAYD_STREAMS_SENT:
+		ret = relay_streams_sent(recv_hdr, cmd);
+		break;
 	case RELAYD_UPDATE_SYNC_INFO:
 	default:
 		ERR("Received unknown command (%u)", be32toh(recv_hdr->cmd));
@@ -2322,6 +2438,7 @@ int relay_add_connection(int fd, struct lttng_poll_event *events,
 		PERROR("read relay cmd pipe");
 		goto error_read;
 	}
+	CDS_INIT_LIST_HEAD(&relay_connection->recv_head);
 
 	/*
 	 * Only used by the control side and the reference is copied inside each
@@ -2373,8 +2490,17 @@ void relay_del_connection(struct lttng_ht *relay_connections_ht,
 	assert(!ret);
 
 	if (relay_connection->type == RELAY_CONTROL) {
+		struct relay_stream_recv_handle *node, *tmp_node;
+
 		relay_delete_session(relay_connection, sessions_ht);
 		lttng_ht_destroy(relay_connection->ctf_traces_ht);
+
+		/* Clean up recv list. */
+		cds_list_for_each_entry_safe(node, tmp_node,
+				&relay_connection->recv_head, node) {
+			cds_list_del(&node->node);
+			free(node);
+		}
 	}
 
 	call_rcu(&relay_connection->rcu_node, deferred_free_connection);