Function virtio_dev_rss_hash_update

dpdk/drivers/net/virtio/virtio_ethdev.c:1555–1600

}

static int
virtio_dev_rss_hash_update(struct rte_eth_dev *dev,
		struct rte_eth_rss_conf *rss_conf)
{
	struct virtio_hw *hw = dev->data->dev_private;
	char old_rss_key[VIRTIO_NET_RSS_KEY_SIZE];
	uint32_t old_hash_types;
	uint16_t nb_queues;
	int ret;

	if (!virtio_with_feature(hw, VIRTIO_NET_F_RSS))
		return -ENOTSUP;

	if (rss_conf->rss_hf & ~virtio_to_ethdev_rss_offloads(VIRTIO_NET_HASH_TYPE_MASK))
		return -EINVAL;

	old_hash_types = hw->rss_hash_types;
	hw->rss_hash_types = ethdev_to_virtio_rss_offloads(rss_conf->rss_hf);

	if (rss_conf->rss_key && rss_conf->rss_key_len) {
		if (rss_conf->rss_key_len != VIRTIO_NET_RSS_KEY_SIZE) {
			PMD_INIT_LOG(ERR, "Driver only supports %u RSS key length",
					VIRTIO_NET_RSS_KEY_SIZE);
			ret = -EINVAL;
			goto restore_types;
		}
		memcpy(old_rss_key, hw->rss_key, VIRTIO_NET_RSS_KEY_SIZE);
		memcpy(hw->rss_key, rss_conf->rss_key, VIRTIO_NET_RSS_KEY_SIZE);
	}

	nb_queues = RTE_MAX(dev->data->nb_rx_queues, dev->data->nb_tx_queues);
	ret = virtio_set_multiple_queues_rss(dev, nb_queues);
	if (ret < 0) {
		PMD_INIT_LOG(ERR, "Failed to apply new RSS config to the device");
		goto restore_key;
	}

	return 0;
restore_key:
	if (rss_conf->rss_key && rss_conf->rss_key_len)
		memcpy(hw->rss_key, old_rss_key, VIRTIO_NET_RSS_KEY_SIZE);
restore_types:
	hw->rss_hash_types = old_hash_types;

	return ret;
}

static int
virtio_dev_rss_hash_conf_get(struct rte_eth_dev *dev,