Re: [dpdk-dev] [PATCH 2/3] ethdev: Add in data rxtx callback support

[Neil Horman <nhorman@tuxdriver.com>]

On Thu, Feb 12, 2015 at 07:57:56PM +0000, John McNamara wrote:
> From: Richardson, Bruce <bruce.richardson@intel.com>
> 
> Add in support for inline processing of packets inside the RX or
> TX call. For an RX callback, what happens is that we get a set of
> packets from the NIC and then pass them to a callback function, if
> configured, to allow additional processing to be done on them, e.g.
> filling in more mbuf fields, before passing back to the application.
> On TX, the packets are similarly post-processed before being handed
> to the NIC for transmission.
> 
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
> ---
>  lib/librte_ether/rte_ethdev.c |  165 +++++++++++++++++++++++++++++++++++++-
>  lib/librte_ether/rte_ethdev.h |  175 ++++++++++++++++++++++++++++++++++++++++-
>  2 files changed, 334 insertions(+), 6 deletions(-)
> 
> diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
> index e4b3315..944737e 100644
> --- a/lib/librte_ether/rte_ethdev.c
> +++ b/lib/librte_ether/rte_ethdev.c
> @@ -337,6 +337,15 @@ rte_eth_dev_rx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
>  			dev->data->nb_rx_queues = 0;
>  			return -(ENOMEM);
>  		}
> +		dev->rx_cbs = rte_zmalloc("ethdev->rx_cbs",
> +				sizeof(*dev->rx_cbs) * nb_queues,
> +				RTE_CACHE_LINE_SIZE);
> +		if (dev->rx_cbs == NULL) {
> +			rte_free(dev->data->rx_queues);
> +			dev->data->rx_queues = NULL;
> +			dev->data->nb_rx_queues = 0;
> +			return -(ENOMEM);
> +		}
>  	} else { /* re-configure */
>  		FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_release, -ENOTSUP);
>  
> @@ -348,10 +357,18 @@ rte_eth_dev_rx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
>  				RTE_CACHE_LINE_SIZE);
>  		if (rxq == NULL)
>  			return -(ENOMEM);
> +		dev->rx_cbs = rte_realloc(dev->rx_cbs, sizeof(*dev->rx_cbs) *
> +				nb_queues, RTE_CACHE_LINE_SIZE);
> +		if (dev->rx_cbs == NULL)
> +			return -(ENOMEM);
>  
> -		if (nb_queues > old_nb_queues)
> +		if (nb_queues > old_nb_queues) {
> +			uint16_t new_qs = nb_queues - old_nb_queues;
>  			memset(rxq + old_nb_queues, 0,
> -				sizeof(rxq[0]) * (nb_queues - old_nb_queues));
> +				sizeof(rxq[0]) * new_qs);
> +			memset(dev->rx_cbs + old_nb_queues, 0,
> +				sizeof(dev->rx_cbs[0]) * new_qs);
> +		}
>  
>  		dev->data->rx_queues = rxq;
>  
> @@ -479,6 +496,15 @@ rte_eth_dev_tx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
>  			dev->data->nb_tx_queues = 0;
>  			return -(ENOMEM);
>  		}
> +		dev->tx_cbs = rte_zmalloc("ethdev->tx_cbs",
> +				sizeof(*dev->tx_cbs) * nb_queues,
> +				RTE_CACHE_LINE_SIZE);
> +		if (dev->tx_cbs == NULL) {
> +			rte_free(dev->data->tx_queues);
> +			dev->data->tx_queues = NULL;
> +			dev->data->nb_tx_queues = 0;
> +			return -(ENOMEM);
> +		}
>  	} else { /* re-configure */
>  		FUNC_PTR_OR_ERR_RET(*dev->dev_ops->tx_queue_release, -ENOTSUP);
>  
> @@ -490,10 +516,19 @@ rte_eth_dev_tx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
>  				RTE_CACHE_LINE_SIZE);
>  		if (txq == NULL)
>  			return -(ENOMEM);
> +		dev->tx_cbs = rte_realloc(dev->tx_cbs, sizeof(*dev->tx_cbs) *
> +				nb_queues, RTE_CACHE_LINE_SIZE);
> +		if (dev->tx_cbs == NULL)
> +			return -(ENOMEM);
> +
>  
> -		if (nb_queues > old_nb_queues)
> +		if (nb_queues > old_nb_queues) {
> +			uint16_t new_qs = nb_queues - old_nb_queues;
>  			memset(txq + old_nb_queues, 0,
> -				sizeof(txq[0]) * (nb_queues - old_nb_queues));
> +				sizeof(txq[0]) * new_qs);
> +			memset(dev->tx_cbs + old_nb_queues, 0,
> +				sizeof(dev->tx_cbs[0]) * new_qs);
> +		}
>  
>  		dev->data->tx_queues = txq;
>  
> @@ -3253,3 +3288,125 @@ rte_eth_dev_filter_ctrl(uint8_t port_id, enum rte_filter_type filter_type,
>  	FUNC_PTR_OR_ERR_RET(*dev->dev_ops->filter_ctrl, -ENOTSUP);
>  	return (*dev->dev_ops->filter_ctrl)(dev, filter_type, filter_op, arg);
>  }
> +
> +void *
> +rte_eth_add_rx_callback(uint8_t port_id, uint16_t queue_id,
> +		rte_rxtx_callback_fn fn, void *user_param)
> +{
These, and its companion manipulator functions need to be added to the ABI
versioning scripts.  As it currently stands this won't be exposed in a shared
build, and so the examples won't build.

Neil