[v6,1/2] app/testpmd: fix max rx packet length for VLAN packets

  When the max rx packet length is smaller than the sum of mtu size and
ether overhead size, it should be enlarged, otherwise the VLAN packets
will be dropped.

Fixes: 35b2d13fd6fd ("net: add rte prefix to ether defines")

Signed-off-by: SteveX Yang <stevex.yang@intel.com>
---
 app/test-pmd/testpmd.c | 52 ++++++++++++++++++++++++++++++------------
 1 file changed, 38 insertions(+), 14 deletions(-)
  

On 10/22/2020 9:48 AM, SteveX Yang wrote:
> When the max rx packet length is smaller than the sum of mtu size and
> ether overhead size, it should be enlarged, otherwise the VLAN packets
> will be dropped.
> 
> Fixes: 35b2d13fd6fd ("net: add rte prefix to ether defines")
> 
> Signed-off-by: SteveX Yang <stevex.yang@intel.com>
> ---
>   app/test-pmd/testpmd.c | 52 ++++++++++++++++++++++++++++++------------
>   1 file changed, 38 insertions(+), 14 deletions(-)
> 
> diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c
> index 33fc0fddf..9031c6145 100644
> --- a/app/test-pmd/testpmd.c
> +++ b/app/test-pmd/testpmd.c
> @@ -1418,9 +1418,13 @@ init_config(void)
>   	unsigned int nb_mbuf_per_pool;
>   	lcoreid_t  lc_id;
>   	uint8_t port_per_socket[RTE_MAX_NUMA_NODES];
> +	struct rte_eth_dev_info *dev_info;
> +	struct rte_eth_conf *dev_conf;
>   	struct rte_gro_param gro_param;
>   	uint32_t gso_types;
>   	uint16_t data_size;
> +	uint16_t overhead_len;
> +	uint16_t frame_size;
>   	bool warning = 0;
>   	int k;
>   	int ret;
> @@ -1448,18 +1452,40 @@ init_config(void)
>   
>   	RTE_ETH_FOREACH_DEV(pid) {
>   		port = &ports[pid];
> +
> +		dev_info = &port->dev_info;
> +		dev_conf = &port->dev_conf;
> +
>   		/* Apply default TxRx configuration for all ports */
> -		port->dev_conf.txmode = tx_mode;
> -		port->dev_conf.rxmode = rx_mode;
> +		dev_conf->txmode = tx_mode;
> +		dev_conf->rxmode = rx_mode;

Hi Steve,

This patch does a small refactoring ('dev_info' & 'dev_conf') and a small 
update, but the refactoring shows the patch more complex than it actually is, if 
you think that is required can you please seperate these two?

>   
> -		ret = eth_dev_info_get_print_err(pid, &port->dev_info);
> +		ret = eth_dev_info_get_print_err(pid, dev_info);
>   		if (ret != 0)
>   			rte_exit(EXIT_FAILURE,
>   				 "rte_eth_dev_info_get() failed\n");
>   
> -		if (!(port->dev_info.tx_offload_capa &
> +		/*
> +		 * Update the max_rx_pkt_len to ensure that its size equals the
> +		 * sum of default mtu size and ether overhead length at least.
> +		 */

What about simplifying the above comment like:
" Update the max_rx_pkt_len to have MTU as RTE_ETHER_MTU "

> +		if (dev_info->max_rx_pktlen && dev_info->max_mtu)
> +			overhead_len =
> +				dev_info->max_rx_pktlen - dev_info->max_mtu;
> +		else
> +			overhead_len =
> +				RTE_ETHER_HDR_LEN + RTE_ETHER_CRC_LEN;
> +
> +		frame_size = RTE_ETHER_MTU + overhead_len;
> +		if (frame_size > RTE_ETHER_MAX_LEN) {
> +			dev_conf->rxmode.max_rx_pkt_len = frame_size;
> +			dev_conf->rxmode.offloads |=
> +				DEV_RX_OFFLOAD_JUMBO_FRAME;

I am not sure the jumbo frame asignment is always true.
'frame_size' can be bigger than 'RTE_ETHER_MAX_LEN', but mtu still can be <= 
1500. What about dropping this?

> +		}
> +
> +		if (!(dev_info->tx_offload_capa &
>   		      DEV_TX_OFFLOAD_MBUF_FAST_FREE))
> -			port->dev_conf.txmode.offloads &=
> +			dev_conf->txmode.offloads &=
>   				~DEV_TX_OFFLOAD_MBUF_FAST_FREE;
>   		if (numa_support) {
>   			if (port_numa[pid] != NUMA_NO_CONFIG)
> @@ -1478,13 +1504,11 @@ init_config(void)
>   		}
>   
>   		/* Apply Rx offloads configuration */
> -		for (k = 0; k < port->dev_info.max_rx_queues; k++)
> -			port->rx_conf[k].offloads =
> -				port->dev_conf.rxmode.offloads;
> +		for (k = 0; k < dev_info->max_rx_queues; k++)
> +			port->rx_conf[k].offloads = dev_conf->rxmode.offloads;
>   		/* Apply Tx offloads configuration */
> -		for (k = 0; k < port->dev_info.max_tx_queues; k++)
> -			port->tx_conf[k].offloads =
> -				port->dev_conf.txmode.offloads;
> +		for (k = 0; k < dev_info->max_tx_queues; k++)
> +			port->tx_conf[k].offloads = dev_conf->txmode.offloads;
>   
>   		/* set flag to initialize port/queue */
>   		port->need_reconfig = 1;
> @@ -1494,10 +1518,10 @@ init_config(void)
>   		/* Check for maximum number of segments per MTU. Accordingly
>   		 * update the mbuf data size.
>   		 */
> -		if (port->dev_info.rx_desc_lim.nb_mtu_seg_max != UINT16_MAX &&
> -				port->dev_info.rx_desc_lim.nb_mtu_seg_max != 0) {
> +		if (dev_info->rx_desc_lim.nb_mtu_seg_max != UINT16_MAX &&
> +				dev_info->rx_desc_lim.nb_mtu_seg_max != 0) {
>   			data_size = rx_mode.max_rx_pkt_len /
> -				port->dev_info.rx_desc_lim.nb_mtu_seg_max;
> +				dev_info->rx_desc_lim.nb_mtu_seg_max;
>   
>   			if ((data_size + RTE_PKTMBUF_HEADROOM) >
>   							mbuf_data_size[0]) {
>