Re: [dpdk-dev] [PATCH] net/i40e: fix multiple interrupt for VF

[Ferruh Yigit <ferruh.yigit@intel.com>]

On 2/17/2020 3:09 AM, Shougang Wang wrote:
> Interrupt mapping should be 1:n queue(s).This patch fixes the
> logic of interrupt bind by code reconstruction.
> 
> Fixes: 6a6cf5f88b4a ("net/i40e: enable multi-queue Rx interrupt for VF")
> 
> Signed-off-by: Shougang Wang <shougangx.wang@intel.com>
> ---
>  drivers/net/i40e/i40e_ethdev_vf.c | 63 ++++++++++++++++++++-----------
>  1 file changed, 42 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/net/i40e/i40e_ethdev_vf.c b/drivers/net/i40e/i40e_ethdev_vf.c
> index b84637309..868117508 100644
> --- a/drivers/net/i40e/i40e_ethdev_vf.c
> +++ b/drivers/net/i40e/i40e_ethdev_vf.c
> @@ -651,47 +651,68 @@ 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) * dev->data->nb_rx_queues];
> +	uint8_t *cmd_buffer = NULL;
>  	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;
> +	uint32_t vec, cmd_buffer_size, max_vectors, nb_msix, msix_base, i;
> +	uint16_t rxq_map[vf->vf_res->max_vectors];
> +	int err;
>  
>  	if (dev->data->dev_conf.intr_conf.rxq != 0 &&
> -	    rte_intr_allow_others(intr_handle))
> -		vector_id = I40E_RX_VEC_START;
> -	else
> -		vector_id = I40E_MISC_VEC_ID;
> +		rte_intr_allow_others(intr_handle)) {
> +		msix_base = I40E_RX_VEC_START;
> +		/* For interrupt mode, available vector id is from 1. */
> +		max_vectors = vf->vf_res->max_vectors - 1;
> +		nb_msix = RTE_MIN(max_vectors, intr_handle->nb_efd);
> +
> +		vec = msix_base;
> +		for (i = 0; i < dev->data->nb_rx_queues; i++) {
> +			rxq_map[vec] |= 1 << i;

ICC is causing following error [1] which looks like a valid one, what do you
thing memset the array before using it?

[1]
.../drivers/net/i40e/i40e_ethdev_vf.c(671): warning #3656: variable "rxq_map"
may be used before its value is set
        rxq_map[vec] |= 1 << i;
        ^