[dpdk-dev] DPDK and HW offloads

[Thomas Monjalon]

2016-03-18 10:16, Stephen Hemminger:
> As I look at how the ethernet device interface in DPDK has exploded in complexity;

Yes I would like to start addressing this complexity in 16.07.

> it makes life very hard for end users.  The goal has been to enable all the cool hardware
> features, but it has put blinders on the driver devlopers; they are ignoring the fact
> that real applications can't just work on one kind of hardware.

+1

> The DPDK is doing a terrible job at providing abstractions.  There needs to be a
> real generic set of operations, and every hardware offload feature must:
>   * have a clear well defined API

+1

>   * if feature is not available in software, then the DPDK must provide
>     a software equivalent feature.

I'm not against this idea. Looking for more opinions.

>   * any difference in API must be hidden from application.
>   * no compile config options about offload.
>   * tests and documentation must work for both hw and sw version
> 
> Right now, all those offload features are pretty much unusable in a real product
> without lots and lots of extra codes and huge bug surface. It bothers me enough
> that I would recommend removing much of the filter/offload/ptype stuff from DPDK!

One of the biggest challenge is to think about a good filtering API.
The offloading has some interaction with the mbuf struct.

I would like to suggest rewriting ethdev API by keeping it as is for some time for
compatibility while creating a new one. What about the prefix dpdk_netdev_ to
progressively replace rte_eth_dev?