Re: [dpdk-stable] [PATCH v1] net/ice: calculate TCP header size for offload

["Yang, Qiming" <qiming.yang@intel.com>]

> -----Original Message-----
> From: Wang, Haiyue <haiyue.wang@intel.com>
> Sent: Wednesday, July 29, 2020 15:51
> To: dev@dpdk.org; Yang, Qiming <qiming.yang@intel.com>; Zhang, Qi Z
> <qi.z.zhang@intel.com>
> Cc: Wang, Yinan <yinan.wang@intel.com>; Xu, Ting <ting.xu@intel.com>;
> Wang, Haiyue <haiyue.wang@intel.com>; stable@dpdk.org
> Subject: [PATCH v1] net/ice: calculate TCP header size for offload
> 
> The ice needs the exact TCP header size including options for TCP checksum
> offload, but according to PKT_TX_TCP_CKSUM note, l4_len is not required to
> be set, so it needs to calculate the TCP header size if not set.
> 
> Fixes: 17c7d0f9d6a4 ("net/ice: support basic Rx/Tx")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
> ---
>  drivers/net/ice/ice_rxtx.c | 27 +++++++++++++++++++++++++++
>  1 file changed, 27 insertions(+)
> 
> diff --git a/drivers/net/ice/ice_rxtx.c b/drivers/net/ice/ice_rxtx.c index
> ddf6a93fb2..bcb67ec251 100644
> --- a/drivers/net/ice/ice_rxtx.c
> +++ b/drivers/net/ice/ice_rxtx.c
> @@ -2371,6 +2371,28 @@ ice_calc_pkt_desc(struct rte_mbuf *tx_pkt)
>  	return count;
>  }
> 
> +/* Calculate TCP header length for PKT_TX_TCP_CKSUM if not provided */
> +static inline uint16_t ice_calc_pkt_tcp_hdr(struct rte_mbuf *tx_pkt,
> +union ice_tx_offload tx_offload) {
> +	uint16_t tcpoff = tx_offload.l2_len + tx_offload.l3_len;
> +	const struct rte_tcp_hdr *tcp_hdr;
> +	struct rte_tcp_hdr _tcp_hdr;
> +
> +	if (tcpoff + sizeof(struct rte_tcp_hdr) < tx_pkt->data_len) {
> +		tcp_hdr = rte_pktmbuf_mtod_offset(tx_pkt, struct
> rte_tcp_hdr *,
> +						  tcpoff);
> +
No need blank line?
> +		return (tcp_hdr->data_off & 0xf0) >> 2;
> +	}
> +
> +	tcp_hdr = rte_pktmbuf_read(tx_pkt, tcpoff, sizeof(_tcp_hdr),
> &_tcp_hdr);
> +	if (tcp_hdr)
> +		return (tcp_hdr->data_off & 0xf0) >> 2;
> +	else
> +		return 0;
> +}
> +
>  uint16_t
>  ice_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t
> nb_pkts)  { @@ -2468,6 +2490,11 @@ ice_xmit_pkts(void *tx_queue, struct
> rte_mbuf **tx_pkts, uint16_t nb_pkts)
> 
>  		/* Enable checksum offloading */
>  		if (ol_flags & ICE_TX_CKSUM_OFFLOAD_MASK) {
> +			if ((ol_flags & PKT_TX_L4_MASK) ==
> PKT_TX_TCP_CKSUM &&
> +			    !tx_offload.l4_len)
> +				tx_offload.l4_len =
> +				     ice_calc_pkt_tcp_hdr(tx_pkt, tx_offload);
> +
>  			ice_txd_enable_checksum(ol_flags, &td_cmd,
>  						&td_offset, tx_offload);
>  		}
> --
> 2.28.0

Acked-by: Qiming Yang <qiming.yang@intel.com>