Re: [dpdk-dev] [PATCH V5 1/2] net/tap: use new Tx offloads API

[Pascal Mazon <pascal.mazon@6wind.com>]

Acked-by: Pascal Mazon <pascal.mazon@6wind.com> for the series.

On 17/01/2018 15:04, Moti Haimovsky wrote:
> Ethdev Tx offloads API has changed since:
> commit cba7f53b717d ("ethdev: introduce Tx queue offloads API")
> This commit adds support for the new Tx offloads API.
>
> Signed-off-by: Moti Haimovsky <motih@mellanox.com>
> ---
> V5:
> * Fixed compilation errors caused by not using PRIx64 in log messages
>   when displaying uint64_t values. 
> * Modified patch name
>
> V3:
> * Fixed coding style warnings
>
> V2:
> * Fixed coding style warnings
> ---
>
>  drivers/net/tap/rte_eth_tap.c | 97 +++++++++++++++++++++++++++++++++++++------
>  drivers/net/tap/rte_eth_tap.h |  1 +
>  2 files changed, 86 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
> index be73f93..7357dce 100644
> --- a/drivers/net/tap/rte_eth_tap.c
> +++ b/drivers/net/tap/rte_eth_tap.c
> @@ -24,6 +24,7 @@
>  #include <sys/mman.h>
>  #include <errno.h>
>  #include <signal.h>
> +#include <stdbool.h>
>  #include <stdint.h>
>  #include <sys/uio.h>
>  #include <unistd.h>
> @@ -346,6 +347,42 @@ enum ioctl_mode {
>  	return num_rx;
>  }
>  
> +static uint64_t
> +tap_tx_offload_get_port_capa(void)
> +{
> +	/*
> +	 * In order to support legacy apps,
> +	 * report capabilities also as port capabilities.
> +	 */
> +	return DEV_TX_OFFLOAD_IPV4_CKSUM |
> +	       DEV_TX_OFFLOAD_UDP_CKSUM |
> +	       DEV_TX_OFFLOAD_TCP_CKSUM;
> +}
> +
> +static uint64_t
> +tap_tx_offload_get_queue_capa(void)
> +{
> +	return DEV_TX_OFFLOAD_IPV4_CKSUM |
> +	       DEV_TX_OFFLOAD_UDP_CKSUM |
> +	       DEV_TX_OFFLOAD_TCP_CKSUM;
> +}
> +
> +static bool
> +tap_txq_are_offloads_valid(struct rte_eth_dev *dev, uint64_t offloads)
> +{
> +	uint64_t port_offloads = dev->data->dev_conf.txmode.offloads;
> +	uint64_t queue_supp_offloads = tap_tx_offload_get_queue_capa();
> +	uint64_t port_supp_offloads = tap_tx_offload_get_port_capa();
> +
> +	if ((offloads & (queue_supp_offloads | port_supp_offloads)) !=
> +	    offloads)
> +		return false;
> +	/* Verify we have no conflict with port offloads */
> +	if ((port_offloads ^ offloads) & port_supp_offloads)
> +		return false;
> +	return true;
> +}
> +
>  static void
>  tap_tx_offload(char *packet, uint64_t ol_flags, unsigned int l2_len,
>  	       unsigned int l3_len)
> @@ -432,9 +469,10 @@ enum ioctl_mode {
>  				rte_pktmbuf_mtod(seg, void *);
>  			seg = seg->next;
>  		}
> -		if (mbuf->ol_flags & (PKT_TX_IP_CKSUM | PKT_TX_IPV4) ||
> -		    (mbuf->ol_flags & PKT_TX_L4_MASK) == PKT_TX_UDP_CKSUM ||
> -		    (mbuf->ol_flags & PKT_TX_L4_MASK) == PKT_TX_TCP_CKSUM) {
> +		if (txq->csum &&
> +		    ((mbuf->ol_flags & (PKT_TX_IP_CKSUM | PKT_TX_IPV4) ||
> +		     (mbuf->ol_flags & PKT_TX_L4_MASK) == PKT_TX_UDP_CKSUM ||
> +		     (mbuf->ol_flags & PKT_TX_L4_MASK) == PKT_TX_TCP_CKSUM))) {
>  			/* Support only packets with all data in the same seg */
>  			if (mbuf->nb_segs > 1)
>  				break;
> @@ -572,6 +610,17 @@ enum ioctl_mode {
>  static int
>  tap_dev_configure(struct rte_eth_dev *dev)
>  {
> +	uint64_t supp_tx_offloads = tap_tx_offload_get_port_capa();
> +	uint64_t tx_offloads = dev->data->dev_conf.txmode.offloads;
> +
> +	if ((tx_offloads & supp_tx_offloads) != tx_offloads) {
> +		rte_errno = ENOTSUP;
> +		RTE_LOG(ERR, PMD,
> +			"Some Tx offloads are not supported "
> +			"requested 0x%" PRIx64 " supported 0x%" PRIx64 "\n",
> +			tx_offloads, supp_tx_offloads);
> +		return -rte_errno;
> +	}
>  	if (dev->data->nb_rx_queues > RTE_PMD_TAP_MAX_QUEUES) {
>  		RTE_LOG(ERR, PMD,
>  			"%s: number of rx queues %d exceeds max num of queues %d\n",
> @@ -648,10 +697,9 @@ enum ioctl_mode {
>  	dev_info->rx_offload_capa = (DEV_RX_OFFLOAD_IPV4_CKSUM |
>  				     DEV_RX_OFFLOAD_UDP_CKSUM |
>  				     DEV_RX_OFFLOAD_TCP_CKSUM);
> -	dev_info->tx_offload_capa =
> -		(DEV_TX_OFFLOAD_IPV4_CKSUM |
> -		 DEV_TX_OFFLOAD_UDP_CKSUM |
> -		 DEV_TX_OFFLOAD_TCP_CKSUM);
> +	dev_info->tx_queue_offload_capa = tap_tx_offload_get_queue_capa();
> +	dev_info->tx_offload_capa = dev_info->tx_queue_offload_capa |
> +				    tap_tx_offload_get_port_capa();
>  }
>  
>  static int
> @@ -1025,21 +1073,46 @@ enum ioctl_mode {
>  		   uint16_t tx_queue_id,
>  		   uint16_t nb_tx_desc __rte_unused,
>  		   unsigned int socket_id __rte_unused,
> -		   const struct rte_eth_txconf *tx_conf __rte_unused)
> +		   const struct rte_eth_txconf *tx_conf)
>  {
>  	struct pmd_internals *internals = dev->data->dev_private;
> +	struct tx_queue *txq;
>  	int ret;
>  
>  	if (tx_queue_id >= dev->data->nb_tx_queues)
>  		return -1;
> -
>  	dev->data->tx_queues[tx_queue_id] = &internals->txq[tx_queue_id];
> +	txq = dev->data->tx_queues[tx_queue_id];
> +	/*
> +	 * Don't verify port offloads for application which
> +	 * use the old API.
> +	 */
> +	if (tx_conf != NULL &&
> +	    !!(tx_conf->txq_flags & ETH_TXQ_FLAGS_IGNORE)) {
> +		if (tap_txq_are_offloads_valid(dev, tx_conf->offloads)) {
> +			txq->csum = !!(tx_conf->offloads &
> +					(DEV_TX_OFFLOAD_IPV4_CKSUM |
> +					 DEV_TX_OFFLOAD_UDP_CKSUM |
> +					 DEV_TX_OFFLOAD_TCP_CKSUM));
> +		} else {
> +			rte_errno = ENOTSUP;
> +			RTE_LOG(ERR, PMD,
> +				"%p: Tx queue offloads 0x%" PRIx64
> +				" don't match port offloads 0x%" PRIx64
> +				" or supported offloads 0x%" PRIx64,
> +				(void *)dev, tx_conf->offloads,
> +				dev->data->dev_conf.txmode.offloads,
> +				tap_tx_offload_get_port_capa());
> +			return -rte_errno;
> +		}
> +	}
>  	ret = tap_setup_queue(dev, internals, tx_queue_id, 0);
>  	if (ret == -1)
>  		return -1;
> -
> -	RTE_LOG(DEBUG, PMD, "  TX TAP device name %s, qid %d on fd %d\n",
> -		internals->name, tx_queue_id, internals->txq[tx_queue_id].fd);
> +	RTE_LOG(DEBUG, PMD,
> +		"  TX TAP device name %s, qid %d on fd %d csum %s\n",
> +		internals->name, tx_queue_id, internals->txq[tx_queue_id].fd,
> +		txq->csum ? "on" : "off");
>  
>  	return 0;
>  }
> diff --git a/drivers/net/tap/rte_eth_tap.h b/drivers/net/tap/rte_eth_tap.h
> index 829f32f..69a1a08 100644
> --- a/drivers/net/tap/rte_eth_tap.h
> +++ b/drivers/net/tap/rte_eth_tap.h
> @@ -76,6 +76,7 @@ struct rx_queue {
>  struct tx_queue {
>  	int fd;
>  	uint16_t *mtu;                  /* Pointer to MTU from dev_data */
> +	uint16_t csum:1;                /* Enable checksum offloading */
>  	struct pkt_stats stats;         /* Stats for this TX queue */
>  };
>