Re: [dpdk-dev] [PATCH 04/32] net/ngbe: support TSO

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 9/8/2021 9:37 AM, Jiawen Wu wrote:
> Add transmit datapath with offloads, and support TCP segmentation
> offload.
> 
> Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>

<...>

> +/* Takes an ethdev and a queue and sets up the tx function to be used based on
> + * the queue parameters. Used in tx_queue_setup by primary process and then
> + * in dev_init by secondary process when attaching to an existing ethdev.
> + */
> +void
> +ngbe_set_tx_function(struct rte_eth_dev *dev, struct ngbe_tx_queue *txq)
> +{
> +	/* Use a simple Tx queue (no offloads, no multi segs) if possible */
> +	if (txq->offloads == 0 &&
> +			txq->tx_free_thresh >= RTE_PMD_NGBE_TX_MAX_BURST) {
> +		PMD_INIT_LOG(DEBUG, "Using simple tx code path");
> +		dev->tx_pkt_burst = ngbe_xmit_pkts_simple;
> +		dev->tx_pkt_prepare = NULL;
> +	} else {
> +		PMD_INIT_LOG(DEBUG, "Using full-featured tx code path");
> +		PMD_INIT_LOG(DEBUG,
> +				" - offloads = 0x%" PRIx64,
> +				txq->offloads);
> +		PMD_INIT_LOG(DEBUG,
> +				" - tx_free_thresh = %lu [RTE_PMD_NGBE_TX_MAX_BURST=%lu]",
> +				(unsigned long)txq->tx_free_thresh,
> +				(unsigned long)RTE_PMD_NGBE_TX_MAX_BURST);
> +		dev->tx_pkt_burst = ngbe_xmit_pkts;
> +		dev->tx_pkt_prepare = ngbe_prep_pkts;
> +	}
> +}

Since driver has multiple Rx/Tx functions now, you may want to implement new
APIs to get info about current burst function (in a separate patch):
'rte_eth_rx_burst_mode_get()'
'rte_eth_tx_burst_mode_get()'