[dpdk-dev] [RFC v4] net/i40e: enable multi-queue Rx interrupt for VF

["lunyuan.cui" <lunyuanx.cui@intel.com>]

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.
After PF sets the map to the register,
all Rx queue interrupts will be received.

In addition, vector id should less than the maximum vector value.
When queue number is more than vector value,
we set up a loop of interrupt vectors map.

Signed-off-by: Lunyuan Cui <lunyuanx.cui@intel.com>
---
v4:
* remove the orginal limit on the interrupt vector value,
  change the limit value with the maximum value which is provided
  by PF.

v3:
* combined 2 lines into 1 line
  before:
	map_info->vecmap[i].rxq_map = 0;
	map_info->vecmap[i].rxq_map |= 1 << i;
  after:
	map_info->vecmap[i].rxq_map = 1 << i;

v2:
* set up a loop of interrupt vectors map from 1 to 4, and sent
  message from VF to PF by one time.
---
 drivers/net/i40e/i40e_ethdev_vf.c | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/drivers/net/i40e/i40e_ethdev_vf.c b/drivers/net/i40e/i40e_ethdev_vf.c
index 308fb9835..406b54fff 100644
--- a/drivers/net/i40e/i40e_ethdev_vf.c
+++ b/drivers/net/i40e/i40e_ethdev_vf.c
@@ -651,12 +651,13 @@ 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;
 	uint32_t vector_id;
 	int i, err;
+	uint16_t nb_msix;
 
 	if (dev->data->dev_conf.intr_conf.rxq != 0 &&
 	    rte_intr_allow_others(intr_handle))
@@ -664,19 +665,25 @@ i40evf_config_irq_map(struct rte_eth_dev *dev)
 	else
 		vector_id = I40E_MISC_VEC_ID;
 
+	nb_msix = RTE_MIN(vf->vf_res->max_vectors,
+			intr_handle->nb_efd);
+
 	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 = 1 << i;
 		if (rte_intr_dp_is_en(intr_handle))
 			intr_handle->intr_vec[i] = vector_id;
+		if (vector_id > I40E_MISC_VEC_ID)
+			vector_id++;
+		if (vector_id > nb_msix)
+			vector_id = I40E_RX_VEC_START;
 	}
 
 	args.ops = VIRTCHNL_OP_CONFIG_IRQ_MAP;
-- 
2.17.1