Re: [dpdk-dev] [PATCH] cryptodev: mark experimental state

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

2015-11-27 15:09, Panu Matilainen:
> On 11/26/2015 03:51 PM, Doherty, Declan wrote:
> > From: Thomas Monjalon [mailto:thomas.monjalon@6wind.com]
> >> 2015-11-26 10:00, Panu Matilainen:
> >>> On 11/26/2015 09:39 AM, Panu Matilainen wrote:
> >>>> I think an experimental library which declares itself exempt from the
> >>>> ABI policy should not be compiled by default. That way anybody wanting
> >>>> to try it out will be forced to notice the experimental status.
> >>>>
> >>>> More generally / longer term, perhaps there should be a
> >>>> CONFIG_RTE_EXPERIMENTAL which wraps all experimental features and
> >>>> defaults to off.
> >>>
> >>> On a related note, librte_mbuf_offload cannot be built if
> >>> CONFIG_RTE_LIBRTE_CRYPTODEV is disabled. Which seems to suggest its (at
> >>> least currently) so tightly couple to cryptodev that perhaps it too
> >>> should be marked experimental and default to off.
> >>
> >> I think you are right.
> >> Declan, what is your opinion?
> >
> >
> > Hey Thomas, yes librte_mbuf_offload should also be set as experimental, it's
> > probably one of the areas which will most likely change in the future.
> >
> > On the issue of turning off experimental libraries in the build by default, my
> > preference would be not to turn them off unless the library has external
> > dependencies, otherwise the possibility of patches being submitted which
> > could break an experimental library will be much higher. In my opinion the
> > fewer build configurations developers have to test against the better.
> 
> What I'm more worried about is users and developers starting to rely on 
> it while still in experimental state, a single comment in the header is 
> really easy to miss.

There are some comments in the config, the header file, doxygen and the release notes.
When using a feature, you have to read the header or the doc.
So would it be better advertised by adding a comment in the doxygen section of
some of the mandatory functions or structures?

> So I'd like to see *some* mechanism which forces users and developers to 
> acknowledge the fact that they're dealing with experimental work. 
> Defaulting to off is one possibility, another one would be wrapping 
> experimental APIs behind a define which you have to set to be able to 
> use the API, eg:
> 
> #if defined(I_KNOW_THIS_IS_EXPERIMENTAL_AND_MAY_EAT_BABIES)
> [...]
> #endif

Are you sure about the babies? ;)