+/**
+ * Configure default RSS reta.
+ *
+ * @param dev
+ * Pointer to Ethernet device structure.
+ *
+ * @return
+ * 0 on success, a negative errno value otherwise and rte_errno is set.
+ */
+int
+mlx5_dev_configure_rss_reta(struct rte_eth_dev *dev)
+{
+ struct mlx5_priv *priv = dev->data->dev_private;
+ unsigned int rxqs_n = dev->data->nb_rx_queues;
+ unsigned int i;
+ unsigned int j;
+ unsigned int reta_idx_n;
+ int ret = 0;
+ unsigned int *rss_queue_arr = NULL;
+ unsigned int rss_queue_n = 0;
+
+ if (priv->skip_default_rss_reta)
+ return ret;
+ rss_queue_arr = rte_malloc("", rxqs_n * sizeof(unsigned int), 0);
+ if (!rss_queue_arr) {
+ DRV_LOG(ERR, "port %u cannot allocate RSS queue list (%u)",
+ dev->data->port_id, rxqs_n);
+ rte_errno = ENOMEM;
+ return -rte_errno;
+ }
+ for (i = 0, j = 0; i < rxqs_n; i++) {
+ struct mlx5_rxq_data *rxq_data;
+ struct mlx5_rxq_ctrl *rxq_ctrl;
+
+ rxq_data = (*priv->rxqs)[i];
+ rxq_ctrl = container_of(rxq_data, struct mlx5_rxq_ctrl, rxq);
+ if (rxq_ctrl && rxq_ctrl->type == MLX5_RXQ_TYPE_STANDARD)
+ rss_queue_arr[j++] = i;
+ }
+ rss_queue_n = j;
+ if (rss_queue_n > priv->config.ind_table_max_size) {
+ DRV_LOG(ERR, "port %u cannot handle this many Rx queues (%u)",
+ dev->data->port_id, rss_queue_n);
+ rte_errno = EINVAL;
+ rte_free(rss_queue_arr);
+ return -rte_errno;
+ }
+ DRV_LOG(INFO, "port %u Rx queues number update: %u -> %u",
+ dev->data->port_id, priv->rxqs_n, rxqs_n);
+ priv->rxqs_n = rxqs_n;
+ /*
+ * If the requested number of RX queues is not a power of two,
+ * use the maximum indirection table size for better balancing.
+ * The result is always rounded to the next power of two.
+ */
+ reta_idx_n = (1 << log2above((rss_queue_n & (rss_queue_n - 1)) ?
+ priv->config.ind_table_max_size :
+ rss_queue_n));
+ ret = mlx5_rss_reta_index_resize(dev, reta_idx_n);
+ if (ret) {
+ rte_free(rss_queue_arr);
+ return ret;
+ }
+ /*
+ * When the number of RX queues is not a power of two,
+ * the remaining table entries are padded with reused WQs
+ * and hashes are not spread uniformly.
+ */
+ for (i = 0, j = 0; (i != reta_idx_n); ++i) {
+ (*priv->reta_idx)[i] = rss_queue_arr[j];
+ if (++j == rss_queue_n)
+ j = 0;
+ }
+ rte_free(rss_queue_arr);
+ return ret;
+}
+