Re: [dpdk-stable] [PATCH] examples/ip_fragmentation: support big packets

[Yongseok Koh <yskoh@mellanox.com>]

> On Dec 26, 2018, at 4:15 AM, Noa Ezra <noae@mellanox.com> wrote:
> 
> In some vendors the RX and TX configuration must be the same,
> therefore the MTU size need to be equal to max_rx_pkt_len.
> The MTU is the largest size packet in bytes that can be sent
> on the network, therefore before changing this parameter,
> the NIC could not receive packets larger than 1500 bytes,
> which is the default MTU size.
> In addition, scatter-gather need to be enabled in order to
> receive frames bigger than mbuf size.
> 
> Cc: stable@dpdk.org
> 
> Signed-off-by: Noa Ezra <noae@mellanox.com>
> ---

Hi Noa,

I can see the same patch in the dev mailing list. You don't need to send the
same fix to stable mailing list separately but you just need to add "Fixes: ..."
tag and "Cc: stable@dpdk.org" to your original patch. Please refer to the
contribution guideline.


Thanks,
Yongseok


> examples/ip_fragmentation/main.c | 17 +++++++++++++----
> 1 file changed, 13 insertions(+), 4 deletions(-)
> 
> diff --git a/examples/ip_fragmentation/main.c b/examples/ip_fragmentation/main.c
> index 17a877d..7420420 100644
> --- a/examples/ip_fragmentation/main.c
> +++ b/examples/ip_fragmentation/main.c
> @@ -141,6 +141,7 @@ struct lcore_queue_conf {
> 		.max_rx_pkt_len = JUMBO_FRAME_MAX_SIZE,
> 		.split_hdr_size = 0,
> 		.offloads = (DEV_RX_OFFLOAD_CHECKSUM |
> +			     DEV_RX_OFFLOAD_SCATTER |
> 			     DEV_RX_OFFLOAD_JUMBO_FRAME),
> 	},
> 	.txmode = {
> @@ -425,7 +426,6 @@ struct rte_lpm6_config lpm6_config = {
> 		 * Read packet from RX queues
> 		 */
> 		for (i = 0; i < qconf->n_rx_queue; i++) {
> -
> 			portid = qconf->rx_queue_list[i].portid;
> 			nb_rx = rte_eth_rx_burst(portid, 0, pkts_burst,
> 						 MAX_PKT_BURST);
> @@ -777,7 +777,6 @@ struct rte_lpm6_config lpm6_config = {
> 			RTE_LOG(INFO, IP_FRAG, "Creating direct mempool on socket %i\n",
> 					socket);
> 			snprintf(buf, sizeof(buf), "pool_direct_%i", socket);
> -
> 			mp = rte_pktmbuf_pool_create(buf, NB_MBUF, 32,
> 				0, RTE_MBUF_DEFAULT_BUF_SIZE, socket);
> 			if (mp == NULL) {
> @@ -892,6 +891,16 @@ struct rte_lpm6_config lpm6_config = {
> 		    dev_info.max_rx_pktlen,
> 		    local_port_conf.rxmode.max_rx_pkt_len);
> 
> +		/* set the mtu to the maximum received packet size */
> +		ret = rte_eth_dev_set_mtu(portid,
> +			local_port_conf.rxmode.max_rx_pkt_len);
> +		if (ret < 0) {
> +			printf("\n");
> +			rte_exit(EXIT_FAILURE, "Set MTU failed: "
> +				"err=%d, port=%d\n",
> +			ret, portid);
> +		}
> +
> 		/* get the lcore_id for this port */
> 		while (rte_lcore_is_enabled(rx_lcore_id) == 0 ||
> 		       qconf->n_rx_queue == (unsigned)rx_queue_per_lcore) {
> @@ -927,7 +936,7 @@ struct rte_lpm6_config lpm6_config = {
> 			local_port_conf.txmode.offloads |=
> 				DEV_TX_OFFLOAD_MBUF_FAST_FREE;
> 		ret = rte_eth_dev_configure(portid, 1, (uint16_t)n_tx_queue,
> -					    &local_port_conf);
> +						&local_port_conf);
> 		if (ret < 0) {
> 			printf("\n");
> 			rte_exit(EXIT_FAILURE, "Cannot configure device: "
> @@ -936,7 +945,7 @@ struct rte_lpm6_config lpm6_config = {
> 		}
> 
> 		ret = rte_eth_dev_adjust_nb_rx_tx_desc(portid, &nb_rxd,
> -					    &nb_txd);
> +					&nb_txd);
> 		if (ret < 0) {
> 			printf("\n");
> 			rte_exit(EXIT_FAILURE, "Cannot adjust number of "
> -- 
> 1.8.3.1
>