Re: [dpdk-dev] [PATCH v3 1/3] fm10k: enable FTAG based forwarding

[Bruce Richardson <bruce.richardson@intel.com>]

On Thu, Feb 04, 2016 at 11:38:47AM +0800, Wang Xiao W wrote:
> This patch enables reading sglort info into mbuf for RX and inserting
> an FTAG at the beginning of the packet for TX. The vlan_tci_outer field
> selected from rte_mbuf structure for sglort is not used in fm10k now.
> In FTAG based forwarding mode, the switch will forward packets according
> to glort info in FTAG rather than mac and vlan table.
> 
> To activate this feature, user needs to turn ``CONFIG_RTE_LIBRTE_FM10K_FTAG_FWD``
> to y in common_linuxapp or common_bsdapp. Currently this feature is supported
> only on PF, because FM10K_PFVTCTL register is read-only for VF.
> 
> Signed-off-by: Wang Xiao W <xiao.w.wang@intel.com>

Any comments on this patch?

My thoughts: is there a way in which this could be done without adding in a new
build time config option?

/Bruce

> ---
>  config/common_bsdapp               |  1 +
>  config/common_linuxapp             |  1 +
>  drivers/net/fm10k/fm10k_ethdev.c   | 12 ++++++++++++
>  drivers/net/fm10k/fm10k_rxtx.c     | 17 +++++++++++++++++
>  drivers/net/fm10k/fm10k_rxtx_vec.c |  9 +++++++++
>  5 files changed, 40 insertions(+)
> 
> diff --git a/config/common_bsdapp b/config/common_bsdapp
> index ed7c31c..451f81a 100644
> --- a/config/common_bsdapp
> +++ b/config/common_bsdapp
> @@ -208,6 +208,7 @@ CONFIG_RTE_LIBRTE_FM10K_DEBUG_TX=n
>  CONFIG_RTE_LIBRTE_FM10K_DEBUG_TX_FREE=n
>  CONFIG_RTE_LIBRTE_FM10K_DEBUG_DRIVER=n
>  CONFIG_RTE_LIBRTE_FM10K_RX_OLFLAGS_ENABLE=y
> +CONFIG_RTE_LIBRTE_FM10K_FTAG_FWD=n
>  
>  #
>  # Compile burst-oriented Mellanox ConnectX-3 (MLX4) PMD
> diff --git a/config/common_linuxapp b/config/common_linuxapp
> index 74bc515..c928bce 100644
> --- a/config/common_linuxapp
> +++ b/config/common_linuxapp
> @@ -207,6 +207,7 @@ CONFIG_RTE_LIBRTE_FM10K_DEBUG_TX_FREE=n
>  CONFIG_RTE_LIBRTE_FM10K_DEBUG_DRIVER=n
>  CONFIG_RTE_LIBRTE_FM10K_RX_OLFLAGS_ENABLE=y
>  CONFIG_RTE_LIBRTE_FM10K_INC_VECTOR=y
> +CONFIG_RTE_LIBRTE_FM10K_FTAG_FWD=n
>  
>  #
>  # Compile burst-oriented Mellanox ConnectX-3 (MLX4) PMD
> diff --git a/drivers/net/fm10k/fm10k_ethdev.c b/drivers/net/fm10k/fm10k_ethdev.c
> index e4aed94..65d355e 100644
> --- a/drivers/net/fm10k/fm10k_ethdev.c
> +++ b/drivers/net/fm10k/fm10k_ethdev.c
> @@ -668,6 +668,18 @@ fm10k_dev_tx_init(struct rte_eth_dev *dev)
>  			PMD_INIT_LOG(ERR, "failed to disable queue %d", i);
>  			return -1;
>  		}
> +#ifdef RTE_LIBRTE_FM10K_FTAG_FWD
> +		/* Enable use of FTAG bit in TX descriptor, PFVTCTL
> +		 * register is read-only for VF.
> +		 */
> +		if (hw->mac.type == fm10k_mac_pf)
> +			FM10K_WRITE_REG(hw, FM10K_PFVTCTL(i),
> +					FM10K_PFVTCTL_FTAG_DESC_ENABLE);
> +		else {
> +			PMD_INIT_LOG(ERR, "FTAG is not supported in VF.");
> +			return -ENOTSUP;
> +		}
> +#endif
>  
>  		/* set location and size for descriptor ring */
>  		FM10K_WRITE_REG(hw, FM10K_TDBAL(i),
> diff --git a/drivers/net/fm10k/fm10k_rxtx.c b/drivers/net/fm10k/fm10k_rxtx.c
> index e958865..f87987d 100644
> --- a/drivers/net/fm10k/fm10k_rxtx.c
> +++ b/drivers/net/fm10k/fm10k_rxtx.c
> @@ -152,6 +152,13 @@ fm10k_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
>  		 */
>  		mbuf->ol_flags |= PKT_RX_VLAN_PKT;
>  		mbuf->vlan_tci = desc.w.vlan;
> +#ifdef RTE_LIBRTE_FM10K_FTAG_FWD
> +		/**
> +		 * mbuf->vlan_tci_outer is an idle field in fm10k driver,
> +		 * so it can be selected to store sglort value.
> +		 */
> +		mbuf->vlan_tci_outer = rte_le_to_cpu_16(desc.w.sglort);
> +#endif
>  
>  		rx_pkts[count] = mbuf;
>  		if (++next_dd == q->nb_desc) {
> @@ -307,6 +314,13 @@ fm10k_recv_scattered_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
>  		 */
>  		mbuf->ol_flags |= PKT_RX_VLAN_PKT;
>  		first_seg->vlan_tci = desc.w.vlan;
> +#ifdef RTE_LIBRTE_FM10K_FTAG_FWD
> +		/**
> +		 * mbuf->vlan_tci_outer is an idle field in fm10k driver,
> +		 * so it can be selected to store sglort value.
> +		 */
> +		first_seg->vlan_tci_outer = rte_le_to_cpu_16(desc.w.sglort);
> +#endif
>  
>  		/* Prefetch data of first segment, if configured to do so. */
>  		rte_packet_prefetch((char *)first_seg->buf_addr +
> @@ -432,6 +446,9 @@ static inline void tx_xmit_pkt(struct fm10k_tx_queue *q, struct rte_mbuf *mb)
>  	q->nb_free -= mb->nb_segs;
>  
>  	q->hw_ring[q->next_free].flags = 0;
> +#ifdef RTE_LIBRTE_FM10K_FTAG_FWD
> +	q->hw_ring[q->next_free].flags |= FM10K_TXD_FLAG_FTAG;
> +#endif
>  	/* set checksum flags on first descriptor of packet. SCTP checksum
>  	 * offload is not supported, but we do not explicitly check for this
>  	 * case in favor of greatly simplified processing. */
> diff --git a/drivers/net/fm10k/fm10k_rxtx_vec.c b/drivers/net/fm10k/fm10k_rxtx_vec.c
> index 2a57eef..0b0f2e3 100644
> --- a/drivers/net/fm10k/fm10k_rxtx_vec.c
> +++ b/drivers/net/fm10k/fm10k_rxtx_vec.c
> @@ -198,7 +198,12 @@ fm10k_rx_vec_condition_check(struct rte_eth_dev *dev)
>  	    rxmode->header_split == 1)
>  		return -1;
>  
> +#ifdef RTE_LIBRTE_FM10K_FTAG_FWD
> +	return -1;
> +#else
>  	return 0;
> +#endif
> +
>  #else
>  	RTE_SET_USED(dev);
>  	return -1;
> @@ -648,7 +653,11 @@ fm10k_tx_vec_condition_check(struct fm10k_tx_queue *txq)
>  	if ((txq->txq_flags & FM10K_SIMPLE_TX_FLAG) != FM10K_SIMPLE_TX_FLAG)
>  		return -1;
>  
> +#ifdef RTE_LIBRTE_FM10K_FTAG_FWD
> +	return -1;
> +#else
>  	return 0;
> +#endif
>  }
>  
>  static inline void
> -- 
> 1.9.3
>