Re: [dpdk-dev] [PATCH v3 3/6] app/testpmd: remove restriction on txpkts set

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

On 9/19/2020 11:47 AM, Wei Hu (Xavier) wrote:
> From: Chengchang Tang <tangchengchang@huawei.com>
> 
> Currently, if nb_txd is not set, the txpkts is not allowed to be set
> because the nb_txd is used to avoid the numer of segments exceed the Tx
> ring size and the default value of nb_txd is 0. And there is a bug that
> nb_txd is the global configuration for Tx ring size and the ring size
> could be changed by some command per queue. So these valid check is
> unreliable and introduced unnecessary constraints.
> 
> This patch adds a valid check function to use the real Tx ring size to
> check the validity of txpkts.
> 
> Fixes: af75078fece3 ("first public release")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Chengchang Tang <tangchengchang@huawei.com>
> Signed-off-by: Wei Hu (Xavier) <xavier.huwei@huawei.com>
> ---
>   app/test-pmd/config.c | 42 ++++++++++++++++++++++++++++++++++++++----
>   1 file changed, 38 insertions(+), 4 deletions(-)
> 
> diff --git a/app/test-pmd/config.c b/app/test-pmd/config.c
> index 4e33208..882de2d 100644
> --- a/app/test-pmd/config.c
> +++ b/app/test-pmd/config.c
> @@ -2984,17 +2984,51 @@ show_tx_pkt_segments(void)
>   	printf("Split packet: %s\n", split);
>   }
>   
> +static bool
> +nb_segs_is_invalid(unsigned int nb_segs)
> +{
> +	uint16_t port_id;
> +
> +	RTE_ETH_FOREACH_DEV(port_id) {
> +		struct rte_port *port = &ports[port_id];
> +		uint16_t ring_size;
> +		uint16_t queue_id;
> +
> +		/*
> +		 * When configure the txq by rte_eth_tx_queue_setup with
> +		 * nb_tx_desc being 0, it will use a default value provided by
> +		 * PMDs to setup this txq. If the default value is 0, it will
> +		 * use the RTE_ETH_DEV_FALLBACK_TX_RINGSIZE to setup this txq.
> +		 */
> +		for (queue_id = 0; queue_id < nb_txq; queue_id++) {
> +			if (port->nb_tx_desc[queue_id])
> +				ring_size = port->nb_tx_desc[queue_id];
> +			else if (port->dev_info.default_txportconf.ring_size)
> +				ring_size =
> +				    port->dev_info.default_txportconf.ring_size;
> +			else
> +				ring_size = RTE_ETH_DEV_FALLBACK_TX_RINGSIZE;
> +
> +			if (ring_size < nb_segs) {
> +				printf("nb segments per TX packets=%u >= TX "
> +				       "queue(%u) ring_size=%u - ignored\n",
> +					nb_segs, queue_id, ring_size);
> +				return true;
> +			}
> +		}

What do you think calling 'rte_eth_rx_queue_info_get()' & 
'rte_eth_tx_queue_info_get()' to get the 'nb_desc'?