Re: [PATCH nft 2/3] meta: add prandom matching

[Florian Westphal <fw@strlen.de>]

Florian Westphal <fw@strlen.de> wrote:
> Patrick McHardy <kaber@trash.net> wrote:
> > > > Any reason why you chose to add this type instead of a generic floating point type?
> > > 
> > > I wanted 0.9999 be tranlated to a value close to UINT32_MAX and 0.00001
> > > to something close to zero so that "meta random 0.999" can be translated to
> > > something like
> > > 
> > > reg1 = prandom_u32()
> > > reg1 <= 0xffffffee
> > > 
> > > I.e. this type cannot represent 5.2 (or whatever).
> > > 
> > > Does that answer your question?
> > 
> > Not really unless I'm misunderstanding your intention. That part is
> > related to the kernel internal representation and could be handled
> > during linearization.
> 
> So what would you suggest?
> Add support for translating double to mpz_t?
> What precisions would you support?

So I've started to generalize the proposed precision type
into type_float which would support 0.000000001 as smallest value.

Does that seem ok or would you use a different precision?
(If so, what & why?)

Thanks!

> What should happen when user asks for meta random 42.23 ?

That still stands, where would this error be detect best?