[dpdk-dev] [PATCH v2 08/16] fm10k: add Vector RX scatter function

[Liang, Cunming]

Hi,

On 10/22/2015 5:44 PM, Chen Jing D(Mark) wrote:
> From: "Chen Jing D(Mark)" <jing.d.chen at intel.com>
>
> Add func fm10k_recv_scattered_pkts_vec to receive chained packets
> with SSE instructions.
>
> Signed-off-by: Chen Jing D(Mark) <jing.d.chen at intel.com>
> ---
>   drivers/net/fm10k/fm10k.h          |    2 +
>   drivers/net/fm10k/fm10k_rxtx_vec.c |   88 ++++++++++++++++++++++++++++++++++++
>   2 files changed, 90 insertions(+), 0 deletions(-)
>
[...]
> +
> +/*
> + * vPMD receive routine that reassembles scattered packets
> + *
> + * Notice:
> + * - don't support ol_flags for rss and csum err
> + * - nb_pkts < RTE_IXGBE_DESCS_PER_LOOP, just return no packet
> + * - nb_pkts > RTE_IXGBE_MAX_RX_BURST, only scan RTE_IXGBE_MAX_RX_BURST
> + *   numbers of DD bit
In order to make sure nb_pkts > RTE_IXGBE_MAX_RX_BURST, it's necessary 
to do RTE_MIN().
> + * - floor align nb_pkts to a RTE_IXGBE_DESC_PER_LOOP power-of-two
> + */
> +uint16_t
> +fm10k_recv_scattered_pkts_vec(void *rx_queue,
> +				struct rte_mbuf **rx_pkts,
> +				uint16_t nb_pkts)
> +{
> +	struct fm10k_rx_queue *rxq = rx_queue;
> +	uint8_t split_flags[RTE_FM10K_MAX_RX_BURST] = {0};
> +	unsigned i = 0;
> +
> +	/* get some new buffers */
> +	uint16_t nb_bufs = fm10k_recv_raw_pkts_vec(rxq, rx_pkts, nb_pkts,
> +			split_flags);
> +	if (nb_bufs == 0)
> +		return 0;
> +
> +	/* happy day case, full burst + no packets to be joined */
> +	const uint64_t *split_fl64 = (uint64_t *)split_flags;
> +	if (rxq->pkt_first_seg == NULL &&
> +			split_fl64[0] == 0 && split_fl64[1] == 0 &&
> +			split_fl64[2] == 0 && split_fl64[3] == 0)
> +		return nb_bufs;
> +
> +	/* reassemble any packets that need reassembly*/
> +	if (rxq->pkt_first_seg == NULL) {
> +		/* find the first split flag, and only reassemble then*/
> +		while (i < nb_bufs && !split_flags[i])
> +			i++;
> +		if (i == nb_bufs)
> +			return nb_bufs;
> +	}
> +	return i + fm10k_reassemble_packets(rxq, &rx_pkts[i], nb_bufs - i,
> +		&split_flags[i]);
> +}