X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fbin%2Flttng-relayd%2Flive.c;h=250d85c6fb39fde7558004f95c198b216b009a6d;hp=3ca1797ed9b07b12468840f0bcd963709f72a92b;hb=3ff5c5db220d92baf64280ba54713fcafe76142e;hpb=dbd6665b396de85a4d6b311c8942f82ea9813891

diff --git a/src/bin/lttng-relayd/live.c b/src/bin/lttng-relayd/live.c
index 3ca1797ed..250d85c6f 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) {
@@ -1188,6 +1222,7 @@ static int try_open_index(struct relay_viewer_stream *vstream,
 	int ret = 0;
 	const uint32_t connection_major = rstream->trace->session->major;
 	const uint32_t connection_minor = rstream->trace->session->minor;
+	enum lttng_trace_chunk_status chunk_status;
 
 	if (vstream->index_file) {
 		goto end;
@@ -1200,14 +1235,19 @@ static int try_open_index(struct relay_viewer_stream *vstream,
 		ret = -ENOENT;
 		goto end;
 	}
-	vstream->index_file = lttng_index_file_create_from_trace_chunk_read_only(
+	chunk_status = lttng_index_file_create_from_trace_chunk_read_only(
 			vstream->stream_file.trace_chunk, rstream->path_name,
 			rstream->channel_name, rstream->tracefile_size,
 			vstream->current_tracefile_id,
 			lttng_to_index_major(connection_major, connection_minor),
-			lttng_to_index_minor(connection_major, connection_minor));
-	if (!vstream->index_file) {
-		ret = -1;
+			lttng_to_index_minor(connection_major, connection_minor),
+			true, &vstream->index_file);
+	if (chunk_status != LTTNG_TRACE_CHUNK_STATUS_OK) {
+		if (chunk_status == LTTNG_TRACE_CHUNK_STATUS_NO_FILE) {
+			ret = -ENOENT;
+		} else {
+			ret = -1;
+		}
 	}
 
 end:
@@ -1426,9 +1466,14 @@ int viewer_get_next_index(struct relay_connection *conn)
 			goto error_put;
 		}
 
+		/*
+		 * It is possible the the file we are trying to open is
+		 * missing if the stream has been closed (application exits with
+		 * per-pid buffers) and a clear command has been performed.
+		 */
 		status = lttng_trace_chunk_open_file(
 				vstream->stream_file.trace_chunk,
-				file_path, O_RDONLY, 0, &fd);
+				file_path, O_RDONLY, 0, &fd, true);
 		if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
 			PERROR("Failed to open trace file for viewer stream");
 			goto error_put;
@@ -1690,7 +1735,23 @@ 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;
 	}
 
@@ -1709,9 +1770,14 @@ int viewer_get_metadata(struct relay_connection *conn)
 			goto error;
 		}
 
+		/*
+		 * It is possible the the metadata file we are trying to open is
+		 * missing if the stream has been closed (application exits with
+		 * per-pid buffers) and a clear command has been performed.
+		 */
 		status = lttng_trace_chunk_open_file(
 				vstream->stream_file.trace_chunk,
-				file_path, O_RDONLY, 0, &fd);
+				file_path, O_RDONLY, 0, &fd, true);
 		if (status != LTTNG_TRACE_CHUNK_STATUS_OK) {
 			PERROR("Failed to open metadata file for viewer stream");
 			goto error;
@@ -1738,12 +1804,6 @@ 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;