Re: [dpdk-dev] [RFC v2] net/i40e: enable multi-queue Rx interrupt for VF

[Ye Xiaolong <xiaolong.ye@intel.com>]

On 09/09, lunyuan.cui wrote:
>This patch enables VF to support multi-queue Rx interrupt.
>
>Current implementation is that only one Rx queue can support interrupt,
>because all queues are mapped in the same vector id in vfio_enable_msix().
>So VF can not support multi-queue Rx interrupt in the interrupt mode.
>
>In this patch, if the packet I/O interrupt on datapath is
>enabled (rte_intr_dp_is_en(intr_handle) is true),
>we map different interrupt vectors to each queue
>and send this map to PF everytime.
>After PF sets the map to the register,
>all Rx queue interrupts will be received.
>
>In addition, because of the i40e performance in ioctl(),
>the maximum supported interrupt vector id is 4.
>If vector id is more than 4, i40e driver will fail to start.
>So when queue number is more than 4,
>we set up a loop of interrupt vectors map from 1 to 4.
>
>Signed-off-by: Lunyuan Cui <lunyuanx.cui@intel.com>
>---
> drivers/net/i40e/i40e_ethdev_vf.c | 28 ++++++++++++++++++----------
> 1 file changed, 18 insertions(+), 10 deletions(-)
>
>diff --git a/drivers/net/i40e/i40e_ethdev_vf.c b/drivers/net/i40e/i40e_ethdev_vf.c
>index 308fb9835..ecfec46f8 100644
>--- a/drivers/net/i40e/i40e_ethdev_vf.c
>+++ b/drivers/net/i40e/i40e_ethdev_vf.c
>@@ -645,13 +645,15 @@ i40evf_configure_vsi_queues(struct rte_eth_dev *dev)
> 	return ret;
> }
> 
>+#define RTE_LIBRTE_I40E_IRQ_NUM_PER_VF  4
>+
> static int
> i40evf_config_irq_map(struct rte_eth_dev *dev)
> {
> 	struct i40e_vf *vf = I40EVF_DEV_PRIVATE_TO_VF(dev->data->dev_private);
> 	struct vf_cmd_info args;
> 	uint8_t cmd_buffer[sizeof(struct virtchnl_irq_map_info) + \
>-		sizeof(struct virtchnl_vector_map)];
>+		sizeof(struct virtchnl_vector_map) * dev->data->nb_rx_queues];
> 	struct virtchnl_irq_map_info *map_info;
> 	struct rte_pci_device *pci_dev = RTE_ETH_DEV_TO_PCI(dev);
> 	struct rte_intr_handle *intr_handle = &pci_dev->intr_handle;
>@@ -665,18 +667,24 @@ i40evf_config_irq_map(struct rte_eth_dev *dev)
> 		vector_id = I40E_MISC_VEC_ID;
> 
> 	map_info = (struct virtchnl_irq_map_info *)cmd_buffer;
>-	map_info->num_vectors = 1;
>-	map_info->vecmap[0].rxitr_idx = I40E_ITR_INDEX_DEFAULT;
>-	map_info->vecmap[0].vsi_id = vf->vsi_res->vsi_id;
>-	/* Alway use default dynamic MSIX interrupt */
>-	map_info->vecmap[0].vector_id = vector_id;
>-	/* Don't map any tx queue */
>-	map_info->vecmap[0].txq_map = 0;
>-	map_info->vecmap[0].rxq_map = 0;
>+	map_info->num_vectors = dev->data->nb_rx_queues;
> 	for (i = 0; i < dev->data->nb_rx_queues; i++) {
>-		map_info->vecmap[0].rxq_map |= 1 << i;
>+		map_info->vecmap[i].rxitr_idx = I40E_ITR_INDEX_DEFAULT;
>+		map_info->vecmap[i].vsi_id = vf->vsi_res->vsi_id;
>+		/* Alway use default dynamic MSIX interrupt */
>+		map_info->vecmap[i].vector_id = vector_id;
>+		/* Don't map any tx queue */
>+		map_info->vecmap[i].txq_map = 0;
>+		map_info->vecmap[i].rxq_map = 0;
>+		map_info->vecmap[i].rxq_map |= 1 << i;

Above 2 lines can combined into

		map_info->vecmap[i].rxq_map = 1 << i;

> 		if (rte_intr_dp_is_en(intr_handle))
> 			intr_handle->intr_vec[i] = vector_id;
>+		if (vector_id > I40E_MISC_VEC_ID) {
>+			if (vector_id < RTE_LIBRTE_I40E_IRQ_NUM_PER_VF)
>+				vector_id++;
>+			else
>+				vector_id = I40E_RX_VEC_START;
>+		}
> 	}
> 
> 	args.ops = VIRTCHNL_OP_CONFIG_IRQ_MAP;
>-- 
>2.17.1
>