Re: [dpdk-dev] [PATCH v4 3/6] app/testpmd: remove restriction on txpkts set

[Slava Ovsiienko <viacheslavo@nvidia.com>]

Hi,  Wei

It was found this patch rejects the --txpkts command line settings.
set_tx_pkt_segments() is called before device started and
we have failure chain:

set_tx_pkt_segments()
  nb_segs_is_invalid()
    get_tx_ring_size ()
     rte_eth_tx_queue_info_get()

It causes --txpkts testpmd command line option is ignored.

With best regards, Slava

> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Wei Hu (Xavier)
> Sent: Friday, September 25, 2020 15:47
> To: dev@dpdk.org
> Cc: xavier.huwei@huawei.com
> Subject: [dpdk-dev] [PATCH v4 3/6] app/testpmd: remove restriction on txpkts
> set
> 
> 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>
> ---
> v3 -> v4:
> 	 add check 'rte_eth_rx_queue_info_get()' return value and
> 	 if it is '-ENOSTUP' calculate the 'ring_size'.
> v3:      initial version.
> ---
>  app/test-pmd/config.c | 64
> +++++++++++++++++++++++++++++++++++++++++++++++----
>  1 file changed, 60 insertions(+), 4 deletions(-)
> 
> diff --git a/app/test-pmd/config.c b/app/test-pmd/config.c index
> 6496d2f..8ebb927 100644
> --- a/app/test-pmd/config.c
> +++ b/app/test-pmd/config.c
> @@ -1893,6 +1893,38 @@ tx_queue_id_is_invalid(queueid_t txq_id)  }
> 
>  static int
> +get_tx_ring_size(portid_t port_id, queueid_t txq_id, uint16_t
> +*ring_size) {
> +	struct rte_port *port = &ports[port_id];
> +	struct rte_eth_txq_info tx_qinfo;
> +	int ret;
> +
> +	ret = rte_eth_tx_queue_info_get(port_id, txq_id, &tx_qinfo);
> +	if (ret == 0) {
> +		*ring_size = tx_qinfo.nb_desc;
> +		return ret;
> +	}
> +
> +	if (ret != -ENOTSUP)
> +		return ret;
> +	/*
> +	 * If the rte_eth_tx_queue_info_get is not support for this PMD,
> +	 * ring_size stored in testpmd will be used for validity verification.
> +	 * 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.
> +	 */
> +	if (port->nb_tx_desc[txq_id])
> +		*ring_size = port->nb_tx_desc[txq_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;
> +	return 0;
> +}
> +
> +static int
>  rx_desc_id_is_invalid(uint16_t rxdesc_id)  {
>  	if (rxdesc_id < nb_rxd)
> @@ -2986,17 +3018,41 @@ show_tx_pkt_segments(void)
>  	printf("Split packet: %s\n", split);
>  }
> 
> +static bool
> +nb_segs_is_invalid(unsigned int nb_segs) {
> +	uint16_t ring_size;
> +	uint16_t queue_id;
> +	uint16_t port_id;
> +	int ret;
> +
> +	RTE_ETH_FOREACH_DEV(port_id) {
> +		for (queue_id = 0; queue_id < nb_txq; queue_id++) {
> +			ret = get_tx_ring_size(port_id, queue_id, &ring_size);
> +
> +			if (ret)
> +				return true;
> +
> +			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;
> +			}
> +		}
> +	}
> +
> +	return false;
> +}
> +
>  void
>  set_tx_pkt_segments(unsigned *seg_lengths, unsigned nb_segs)  {
>  	uint16_t tx_pkt_len;
>  	unsigned i;
> 
> -	if (nb_segs >= (unsigned) nb_txd) {
> -		printf("nb segments per TX packets=%u >= nb_txd=%u -
> ignored\n",
> -		       nb_segs, (unsigned int) nb_txd);
> +	if (nb_segs_is_invalid(nb_segs))
>  		return;
> -	}
> 
>  	/*
>  	 * Check that each segment length is greater or equal than
> --
> 2.9.5