On Wed, Dec 09, 2015 at 01:58:57PM +0100, Thomas Graf wrote:

So if the goal is to make the intent available to the hardware in
a format which both the kernel and the hardware can draw the same
conclusions from, wouldn't something like P4 + BPF derived from P4
be a possibly better fit? There is discussion on stateful P4
processing now.

p4 is a high level language and absolutely not suitable for such purpose.
bpf as intermediate representation can be generated from p4 or C or other
language. There is room to innovate in the language definition on top
and in HW design at the bottom. That's the most flexible model.