Re: [dpdk-stable] [PATCH] bus/pci: fix Windows kernel driver categories

[Ranjit Menon <ranjit.menon@intel.com>]

Hi Thomas,

On 3/16/2021 4:11 PM, Thomas Monjalon wrote:
> In Windows probing, the value RTE_PCI_KDRV_NONE was used
> instead of RTE_PCI_KDRV_UNKNOWN (mlx case),
> and RTE_PCI_KDRV_NIC_UIO (FreeBSD) was re-used
> instead of having a new RTE_PCI_KDRV_NET_UIO for Windows NetUIO.
Shouldn't the mlx case actually remain RTE_PCI_KDRV_NONE?

mlx does not require a UIO-like kernel driver...No? And NONE implies that no kernel driver is used/required.
Not sure what is correct here.

> While adding the new value RTE_PCI_KDRV_NET_UIO,
> the enum of kernel driver categories is annotated.
>
> Fixes: b762221ac24f ("bus/pci: support Windows with bifurcated drivers")
> Fixes: c76ec01b4591 ("bus/pci: support netuio on Windows")
> Cc: stable@dpdk.org
>
> Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
> ---
>   drivers/bus/pci/rte_bus_pci.h | 13 +++++++------
>   drivers/bus/pci/windows/pci.c | 14 +++++++-------
>   2 files changed, 14 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/bus/pci/rte_bus_pci.h b/drivers/bus/pci/rte_bus_pci.h
> index fdda046515..3d009cc74b 100644
> --- a/drivers/bus/pci/rte_bus_pci.h
> +++ b/drivers/bus/pci/rte_bus_pci.h
> @@ -52,12 +52,13 @@ TAILQ_HEAD(rte_pci_driver_list, rte_pci_driver);
>   struct rte_devargs;
>   
>   enum rte_pci_kernel_driver {
> -	RTE_PCI_KDRV_UNKNOWN = 0,
> -	RTE_PCI_KDRV_IGB_UIO,
> -	RTE_PCI_KDRV_VFIO,
> -	RTE_PCI_KDRV_UIO_GENERIC,
> -	RTE_PCI_KDRV_NIC_UIO,
> -	RTE_PCI_KDRV_NONE,
> +	RTE_PCI_KDRV_UNKNOWN = 0,  /* not listed - may be a bifurcated driver */
> +	RTE_PCI_KDRV_IGB_UIO,      /* igb_uio for Linux */
> +	RTE_PCI_KDRV_VFIO,         /* VFIO for Linux */
> +	RTE_PCI_KDRV_UIO_GENERIC,  /* uio_generic for Linux */
> +	RTE_PCI_KDRV_NIC_UIO,      /* nic_uio for FreeBSD */
> +	RTE_PCI_KDRV_NONE,         /* error */
> +	RTE_PCI_KDRV_NET_UIO,      /* NetUIO for Windows */
>   };
>   

Any chance we can re-order the enums, so that _NONE and _UNKNOWN are at 
the top?

This will change the value, and break code where this value was 
hard-coded. But how likely is that...?

ranjit m.

>   /**
> diff --git a/drivers/bus/pci/windows/pci.c b/drivers/bus/pci/windows/pci.c
> index 8f906097f4..3f0ce1fb83 100644
> --- a/drivers/bus/pci/windows/pci.c
> +++ b/drivers/bus/pci/windows/pci.c
> @@ -38,7 +38,7 @@ rte_pci_map_device(struct rte_pci_device *dev)
>   	 * Devices that are bound to netuio are mapped at
>   	 * the bus probing stage.
>   	 */
> -	if (dev->kdrv == RTE_PCI_KDRV_NIC_UIO)
> +	if (dev->kdrv == RTE_PCI_KDRV_NET_UIO)
>   		return 0;
>   	else
>   		return -1;
> @@ -207,14 +207,14 @@ get_device_resource_info(HDEVINFO dev_info,
>   	int ret;
>   
>   	switch (dev->kdrv) {
> -	case RTE_PCI_KDRV_NONE:
> -		/* mem_resource - Unneeded for RTE_PCI_KDRV_NONE */
> +	case RTE_PCI_KDRV_UNKNOWN:
> +		/* mem_resource is unneeded */
>   		dev->mem_resource[0].phys_addr = 0;
>   		dev->mem_resource[0].len = 0;
>   		dev->mem_resource[0].addr = NULL;
>   		break;
> -	case RTE_PCI_KDRV_NIC_UIO:
> -		/* get device info from netuio kernel driver */
> +	case RTE_PCI_KDRV_NET_UIO:
> +		/* get device info from NetUIO kernel driver */
>   		ret = get_netuio_device_info(dev_info, dev_info_data, dev);
>   		if (ret != 0) {
>   			RTE_LOG(DEBUG, EAL,
> @@ -323,9 +323,9 @@ set_kernel_driver_type(PSP_DEVINFO_DATA device_info_data,
>   {
>   	/* set kernel driver type based on device class */
>   	if (IsEqualGUID(&(device_info_data->ClassGuid), &GUID_DEVCLASS_NETUIO))
> -		dev->kdrv = RTE_PCI_KDRV_NIC_UIO;
> +		dev->kdrv = RTE_PCI_KDRV_NET_UIO;
>   	else
> -		dev->kdrv = RTE_PCI_KDRV_NONE;
> +		dev->kdrv = RTE_PCI_KDRV_UNKNOWN;
>   }
>   
>   static int