Re: [dpdk-dev] Poor device abstraction's

[Neil Horman <nhorman@tuxdriver.com>]

On Fri, Apr 11, 2014 at 10:33:31AM -0700, Stephen Hemminger wrote:
> One of my pet peeve's is that the device driver config does not abstract
> the properties of the Ethernet device. The existing parameters match those
> of Intel's Ethernet hardware but not much else. It also makes it hard
> to write generic applications.  If the application has to query the
> device driver name string and insert different parameters for igb, igbvf, ixgbe
> and vmxnet3 then the API was designed wrong.
> 
I agree.  I think the patches that recently got integrated from Olivier are a
step toward fixing that, but theres some more work to be done.

Neil

> Specific examples:
>   * the "descriptors" argument to rx/tx is interpreted as a hardware resource
>     not the number of packets. An application really wants to say "you may buffer
>     up to 100us of packets" not have to guess what the underlying driver does.
> 
>   * the rthresh/wthresh/pthresh are PCI device artifacts and correct value is
>     different for each HW device shouldn't be exposed to application. The API
>     should be something like "device may burst up to N packets and/or T latency".
> 
> These seems like issues of a transition from a cool toy to talk to Intel hardware
> to a useful application infrastructure.
> 
> That is why I would hate to see the existing Intel device centric API frozen.
>