Re: [dpdk-dev] [PATCH] librte_pmd_packet: add PMD for AF_PACKET-based virtual devices

[Thomas Monjalon <thomas.monjalon@6wind.com>]

2014-07-10 16:32, John W. Linville:
> This is a Linux-specific virtual PMD driver backed by an AF_PACKET
> socket.  This implementation uses mmap'ed ring buffers to limit copying
> and user/kernel transitions.  The PACKET_FANOUT_HASH behavior of
> AF_PACKET is used for frame reception.  In the current implementation,
> Tx and Rx queues are always paired, and therefore are always equal
> in number -- changing this would be a Simple Matter Of Programming.
> 
> Interfaces of this type are created with a command line option like
> "--vdev=eth_packet0,iface=...".  There are a number of options availabe
> as arguments:
> 
>  - Interface is chosen by "iface" (required)
>  - Number of queue pairs set by "qpairs" (optional, default: 16)
>  - AF_PACKET MMAP block size set by "blocksz" (optional, default: 4096)
>  - AF_PACKET MMAP frame size set by "framesz" (optional, default: 2048)
>  - AF_PACKET MMAP frame count set by "framecnt" (optional, default: 512)
> 
> Signed-off-by: John W. Linville <linville@tuxdriver.com>
> ---
> This PMD is intended to provide a means for using DPDK on a broad
> range of hardware without hardware-specific PMDs and (hopefully)
> with better performance than what PCAP offers in Linux.  This might
> be useful as a development platform for DPDK applications when
> DPDK-supported hardware is expensive or unavailable.

Thank you for this nice work.

I think it would be well suited to host this PMD as an external one in order 
to make it work also with DPDK 1.7.0.

-- 
Thomas