+ 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:
+ rcu_read_unlock();
+ return ret;
+}
+
+/*
+ * Clear quiescent state from channel's streams using the given key to
+ * retrieve the channel.
+ *
+ * Return 0 on success else an LTTng error code.
+ */
+static int clear_quiescent_channel(uint64_t chan_key)
+{
+ int ret = 0;
+ struct lttng_consumer_channel *channel;
+ struct lttng_consumer_stream *stream;
+ struct lttng_ht *ht;
+ struct lttng_ht_iter iter;
+
+ DBG("UST consumer clear quiescent channel key %" PRIu64, chan_key);
+
+ rcu_read_lock();
+ channel = consumer_find_channel(chan_key);
+ if (!channel) {
+ ERR("UST consumer clear quiescent channel %" PRIu64 " not found", chan_key);
+ ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
+ goto error;
+ }
+
+ ht = consumer_data.stream_per_chan_id_ht;
+
+ /* For each stream of the channel id, clear quiescent state. */
+ cds_lfht_for_each_entry_duplicate(ht->ht,
+ ht->hash_fct(&channel->key, lttng_ht_seed), ht->match_fct,
+ &channel->key, &iter.iter, stream, node_channel_id.node) {
+
+ health_code_update();
+
+ pthread_mutex_lock(&stream->lock);
+ stream->quiescent = false;
+ pthread_mutex_unlock(&stream->lock);