[PATCH v6 05/16] vdpa/ifc: add vDPA interrupt for blk device

[Xia, Chenbo]

Hi Andy,

> -----Original Message-----
> From: Pei, Andy <andy.pei at intel.com>
> Sent: Thursday, April 21, 2022 4:34 PM
> To: dev at dpdk.org
> Cc: Xia, Chenbo <chenbo.xia at intel.com>; maxime.coquelin at redhat.com; Cao,
> Gang <gang.cao at intel.com>; Liu, Changpeng <changpeng.liu at intel.com>
> Subject: [PATCH v6 05/16] vdpa/ifc: add vDPA interrupt for blk device
> 
> For the block device type, we have to relay
> the commands on all queues.

It's a bit short... although I can understand, please add some background
on current implementation for others to easily understand.

> 
> Signed-off-by: Andy Pei <andy.pei at intel.com>
> ---
>  drivers/vdpa/ifc/ifcvf_vdpa.c | 46 ++++++++++++++++++++++++++++++++------
> -----
>  1 file changed, 35 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/vdpa/ifc/ifcvf_vdpa.c b/drivers/vdpa/ifc/ifcvf_vdpa.c
> index 8ee041f..8d104b7 100644
> --- a/drivers/vdpa/ifc/ifcvf_vdpa.c
> +++ b/drivers/vdpa/ifc/ifcvf_vdpa.c
> @@ -370,24 +370,48 @@ struct rte_vdpa_dev_info {
>  	irq_set->index = VFIO_PCI_MSIX_IRQ_INDEX;
>  	irq_set->start = 0;
>  	fd_ptr = (int *)&irq_set->data;
> +	/* The first interrupt is for the configure space change
> notification */
>  	fd_ptr[RTE_INTR_VEC_ZERO_OFFSET] =
>  		rte_intr_fd_get(internal->pdev->intr_handle);
> 
>  	for (i = 0; i < nr_vring; i++)
>  		internal->intr_fd[i] = -1;
> 
> -	for (i = 0; i < nr_vring; i++) {
> -		rte_vhost_get_vhost_vring(internal->vid, i, &vring);
> -		fd_ptr[RTE_INTR_VEC_RXTX_OFFSET + i] = vring.callfd;
> -		if ((i & 1) == 0 && m_rx == true) {
> -			fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
> -			if (fd < 0) {
> -				DRV_LOG(ERR, "can't setup eventfd: %s",
> -					strerror(errno));
> -				return -1;
> +	if (internal->device_type == IFCVF_NET) {
> +		for (i = 0; i < nr_vring; i++) {
> +			rte_vhost_get_vhost_vring(internal->vid, i, &vring);
> +			fd_ptr[RTE_INTR_VEC_RXTX_OFFSET + i] = vring.callfd;
> +			if ((i & 1) == 0 && m_rx == true) {
> +				/* For the net we only need to relay rx queue,
> +				 * which will change the mem of VM.
> +				 */
> +				fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
> +				if (fd < 0) {
> +					DRV_LOG(ERR, "can't setup eventfd: %s",
> +						strerror(errno));
> +					return -1;
> +				}
> +				internal->intr_fd[i] = fd;
> +				fd_ptr[RTE_INTR_VEC_RXTX_OFFSET + i] = fd;
> +			}
> +		}
> +	} else if (internal->device_type == IFCVF_BLK) {
> +		for (i = 0; i < nr_vring; i++) {
> +			rte_vhost_get_vhost_vring(internal->vid, i, &vring);
> +			fd_ptr[RTE_INTR_VEC_RXTX_OFFSET + i] = vring.callfd;
> +			if (m_rx == true) {
> +				/* For the blk we need to relay all the read cmd
> +				 * of each queue
> +				 */
> +				fd = eventfd(0, EFD_NONBLOCK | EFD_CLOEXEC);
> +				if (fd < 0) {
> +					DRV_LOG(ERR, "can't setup eventfd: %s",
> +						strerror(errno));
> +					return -1;
> +				}
> +				internal->intr_fd[i] = fd;
> +				fd_ptr[RTE_INTR_VEC_RXTX_OFFSET + i] = fd;

Many duplicated code here for blk and net. What if we use this condition to know
creating eventfd or not:

if (m_rx == true && (is_blk_dev || (i & 1) == 0)) {
	/* create eventfd and save now */
}

Thanks,
Chenbo

>  			}
> -			internal->intr_fd[i] = fd;
> -			fd_ptr[RTE_INTR_VEC_RXTX_OFFSET + i] = fd;
>  		}
>  	}
> 
> --
> 1.8.3.1