X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=src%2Fcommon%2Fust-consumer%2Fust-consumer.c;h=878e2e2212b6613d2de394783462248526d57529;hb=fd9b5d0f402623ffdc908a2fecc9d088f82110e9;hp=5b8e9431f9ca15d2dbba787442863650fe343453;hpb=85aa60d7724d9398c1c0c958056bc38009cf0381;p=lttng-tools.git

diff --git a/src/common/ust-consumer/ust-consumer.c b/src/common/ust-consumer/ust-consumer.c
index 5b8e9431f..878e2e221 100644
--- a/src/common/ust-consumer/ust-consumer.c
+++ b/src/common/ust-consumer/ust-consumer.c
@@ -768,10 +768,19 @@ static int flush_channel(uint64_t chan_key)
 		health_code_update();
 
 		pthread_mutex_lock(&stream->lock);
+
+		/*
+		 * Protect against concurrent teardown of a stream.
+		 */
+		if (cds_lfht_is_node_deleted(&stream->node.node)) {
+			goto next;
+		}
+
 		if (!stream->quiescent) {
 			ustctl_flush_buffer(stream->ustream, 0);
 			stream->quiescent = true;
 		}
+next:
 		pthread_mutex_unlock(&stream->lock);
 	}
 error:
@@ -1174,7 +1183,7 @@ static int snapshot_channel(uint64_t key, char *path, uint64_t relayd_id,
 				produced_pos, nb_packets_per_stream,
 				stream->max_sb_size);
 
-		while (consumed_pos < produced_pos) {
+		while ((long) (consumed_pos - produced_pos) < 0) {
 			ssize_t read_len;
 			unsigned long len, padded_len;
 
@@ -2321,6 +2330,13 @@ int commit_one_metadata_packet(struct lttng_consumer_stream *stream)
 			stream->ust_metadata_pushed);
 	ret = write_len;
 
+	/*
+	 * Switch packet (but don't open the next one) on every commit of
+	 * a metadata packet. Since the subbuffer is fully filled (with padding,
+	 * if needed), the stream is "quiescent" after this commit.
+	 */
+	ustctl_flush_buffer(stream->ustream, 1);
+	stream->quiescent = true;
 end:
 	pthread_mutex_unlock(&stream->chan->metadata_cache->lock);
 	return ret;
@@ -2365,7 +2381,6 @@ int lttng_ustconsumer_sync_metadata(struct lttng_consumer_local_data *ctx,
 		retry = 1;
 	}
 
-	ustctl_flush_buffer(metadata->ustream, 1);
 	ret = ustctl_snapshot(metadata->ustream);
 	if (ret < 0) {
 		if (errno != EAGAIN) {
@@ -2555,7 +2570,6 @@ retry:
 			if (ret <= 0) {
 				goto end;
 			}
-			ustctl_flush_buffer(stream->ustream, 1);
 			goto retry;
 		}
 
@@ -2922,7 +2936,7 @@ int lttng_ustconsumer_request_metadata(struct lttng_consumer_local_data *ctx,
 	request.key = channel->key;
 
 	DBG("Sending metadata request to sessiond, session id %" PRIu64
-			", per-pid %" PRIu64 ", app UID %u and channek key %" PRIu64,
+			", per-pid %" PRIu64 ", app UID %u and channel key %" PRIu64,
 			request.session_id, request.session_id_per_pid, request.uid,
 			request.key);