X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=src%2Fbin%2Flttng-relayd%2Flive.c;h=0355cf9d91f06cf95c62a84efd61ccb07fa29f60;hb=883b91c5a6b247de16c816e7772a945fd43cc216;hp=7a62059ee8f7a9dadf8d84005e642f746eb7d806;hpb=c6446a541f7c281f1c7f957d0cb945282efbec0b;p=lttng-tools.git

diff --git a/src/bin/lttng-relayd/live.c b/src/bin/lttng-relayd/live.c
index 7a62059ee..0355cf9d9 100644
--- a/src/bin/lttng-relayd/live.c
+++ b/src/bin/lttng-relayd/live.c
@@ -1180,7 +1180,12 @@ int viewer_get_new_streams(struct relay_connection *conn)
 			LTTNG_VIEWER_SEEK_BEGINNING, &nb_total, &nb_unsent,
 			&nb_created, &closed);
 	if (ret < 0) {
-		goto error_unlock_session;
+		/*
+		 * This is caused by an internal error; propagate the negative
+		 * 'ret' to close the connection.
+		 */
+		response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_ERR);
+		goto send_reply_unlock;
 	}
 	send_streams = 1;
 	response.status = htobe32(LTTNG_VIEWER_NEW_STREAMS_OK);
@@ -1235,10 +1240,6 @@ end_put_session:
 	}
 error:
 	return ret;
-error_unlock_session:
-	pthread_mutex_unlock(&session->lock);
-	session_put(session);
-	return ret;
 }
 
 /*
@@ -1983,6 +1984,7 @@ int viewer_get_metadata(struct relay_connection *conn)
 	struct lttng_viewer_get_metadata request;
 	struct lttng_viewer_metadata_packet reply;
 	struct relay_viewer_stream *vstream = NULL;
+	bool dispose_of_stream = false;
 
 	assert(conn);
 
@@ -2013,6 +2015,9 @@ int viewer_get_metadata(struct relay_connection *conn)
 		reply.status = htobe32(LTTNG_VIEWER_METADATA_ERR);
 		goto send_reply;
 	}
+
+	pthread_mutex_lock(&vstream->stream->trace->session->lock);
+	pthread_mutex_lock(&vstream->stream->trace->lock);
 	pthread_mutex_lock(&vstream->stream->lock);
 	if (!vstream->stream->is_metadata) {
 		ERR("Invalid metadata stream");
@@ -2021,11 +2026,7 @@ int viewer_get_metadata(struct relay_connection *conn)
 
 	if (vstream->metadata_sent >= vstream->stream->metadata_received) {
 		/*
-		 * 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.
-		 *
-		 * Clear feature resets the metadata_sent to 0 until the
+		 * Clear feature resets the metadata_received to 0 until the
 		 * same metadata is received again.
 		 */
 		reply.status = htobe32(LTTNG_VIEWER_NO_NEW_METADATA);
@@ -2033,13 +2034,7 @@ int viewer_get_metadata(struct relay_connection *conn)
 		 * The live viewer considers a closed 0 byte metadata stream as
 		 * an error.
 		 */
-		if (vstream->metadata_sent > 0) {
-			if (vstream->stream->closed && vstream->stream->no_new_metadata_notified) {
-				/* Release ownership for the viewer metadata stream. */
-				viewer_stream_put(vstream);
-			}
-			vstream->stream->no_new_metadata_notified = true;
-		}
+		dispose_of_stream = vstream->metadata_sent > 0 && vstream->stream->closed;
 		goto send_reply;
 	}
 
@@ -2079,6 +2074,19 @@ int viewer_get_metadata(struct relay_connection *conn)
 	len = vstream->stream->metadata_received - vstream->metadata_sent;
 
 	if (!vstream->stream_file.trace_chunk) {
+		if (vstream->stream->trace->session->connection_closed) {
+			/*
+			 * If the connection is closed, there is no way for the metadata stream
+			 * to ever transition back to an active chunk. As such, signal to the viewer
+			 * that there is no new metadata available.
+			 *
+			 * The stream can be disposed-of. On the next execution of this command,
+			 * the relay daemon will reply with an error status since the stream can't
+			 * be found.
+			 */
+			dispose_of_stream = true;
+		}
+
 		reply.status = htobe32(LTTNG_VIEWER_NO_NEW_METADATA);
 		len = 0;
 		goto send_reply;
@@ -2208,6 +2216,8 @@ send_reply:
 	health_code_update();
 	if (vstream) {
 		pthread_mutex_unlock(&vstream->stream->lock);
+		pthread_mutex_unlock(&vstream->stream->trace->lock);
+		pthread_mutex_unlock(&vstream->stream->trace->session->lock);
 	}
 	ret = send_response(conn->sock, &reply, sizeof(reply));
 	if (ret < 0) {
@@ -2232,7 +2242,22 @@ end_free:
 end:
 	if (vstream) {
 		viewer_stream_put(vstream);
+		if (dispose_of_stream) {
+			/*
+			 * Trigger the destruction of the viewer stream
+			 * by releasing its global reference.
+			 *
+			 * 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.
+			 *
+			 * On the next query for this stream, an error will be reported to the
+			 * client.
+			 */
+			viewer_stream_put(vstream);
+		}
 	}
+
 	return ret;
 }