X-Git-Url: http://git.efficios.com/?a=blobdiff_plain;f=src%2Fbin%2Flttng-relayd%2Flive.c;h=1b25671d5f76a82ad83a33ceceb3691e8794457c;hb=cc280027af4d65437a30613bb63421ae8d7b199a;hp=3ca1797ed9b07b12468840f0bcd963709f72a92b;hpb=dbd6665b396de85a4d6b311c8942f82ea9813891;p=lttng-tools.git

diff --git a/src/bin/lttng-relayd/live.c b/src/bin/lttng-relayd/live.c
index 3ca1797ed..1b25671d5 100644
--- a/src/bin/lttng-relayd/live.c
+++ b/src/bin/lttng-relayd/live.c
@@ -309,6 +309,7 @@ static int make_viewer_streams(struct relay_session *session,
 	rcu_read_lock();
 	cds_lfht_for_each_entry(session->ctf_traces_ht->ht, &iter.iter, ctf_trace,
 			node.node) {
+		bool trace_has_metadata_stream = false;
 		struct relay_stream *stream;
 
 		health_code_update();
@@ -317,6 +318,30 @@ static int make_viewer_streams(struct relay_session *session,
 			continue;
 		}
 
+		/*
+		 * Iterate over all the streams of the trace to see if we have a
+		 * metadata stream.
+		 */
+		cds_list_for_each_entry_rcu(
+				stream, &ctf_trace->stream_list, stream_node)
+		{
+			if (stream->is_metadata) {
+				trace_has_metadata_stream = true;
+				break;
+			}
+		}
+
+		/*
+		 * If there is no metadata stream in this trace at the moment
+		 * and we never sent one to the viewer, skip the trace. We
+		 * accept that the viewer will not see this trace at all.
+		 */
+		if (!trace_has_metadata_stream &&
+				!ctf_trace->metadata_stream_sent_to_viewer) {
+			ctf_trace_put(ctf_trace);
+			continue;
+		}
+
 		cds_list_for_each_entry_rcu(stream, &ctf_trace->stream_list, stream_node) {
 			struct relay_viewer_stream *vstream;
 
@@ -331,6 +356,15 @@ static int make_viewer_streams(struct relay_session *session,
 			}
 			vstream = viewer_stream_get_by_id(stream->stream_handle);
 			if (!vstream) {
+				/*
+				 * Save that we sent the metadata stream to the
+				 * viewer. So that we know what trace the viewer
+				 * is aware of.
+				 */
+				if (stream->is_metadata) {
+					ctf_trace->metadata_stream_sent_to_viewer =
+							true;
+				}
 				vstream = viewer_stream_create(stream,
 						viewer_trace_chunk, seek_t);
 				if (!vstream) {
@@ -1690,7 +1724,23 @@ int viewer_get_metadata(struct relay_connection *conn)
 
 	len = vstream->stream->metadata_received - vstream->metadata_sent;
 	if (len == 0) {
+		/*
+		 * The live viewers expect to receive a NO_NEW_METADATA
+		 * status before a stream disappears, otherwise they abort the
+		 * entire live connection when receiving an error status.
+		 */
 		reply.status = htobe32(LTTNG_VIEWER_NO_NEW_METADATA);
+		/*
+		 * The live viewer considers a closed 0 byte metadata stream as
+		 * an error.
+		 */
+		if (vstream->metadata_sent > 0) {
+			vstream->stream->no_new_metadata_notified = true;
+			if (vstream->stream->closed) {
+				/* Release ownership for the viewer metadata stream. */
+				viewer_stream_put(vstream);
+			}
+		}
 		goto send_reply;
 	}
 
@@ -1738,12 +1788,6 @@ int viewer_get_metadata(struct relay_connection *conn)
 		goto error;
 	}
 	vstream->metadata_sent += read_len;
-	if (vstream->metadata_sent == vstream->stream->metadata_received
-			&& vstream->stream->closed) {
-		/* Release ownership for the viewer metadata stream. */
-		viewer_stream_put(vstream);
-	}
-
 	reply.status = htobe32(LTTNG_VIEWER_METADATA_OK);
 
 	goto send_reply;