Re: [dpdk-dev] doc: deprecation notice for ethdev ops?

["Dumitrescu, Cristian" <cristian.dumitrescu@intel.com>]

> -----Original Message-----
> From: Yigit, Ferruh
> Sent: Monday, February 13, 2017 4:46 PM
> To: Thomas Monjalon <thomas.monjalon@6wind.com>; Dumitrescu, Cristian
> <cristian.dumitrescu@intel.com>
> Cc: dev@dpdk.org; Richardson, Bruce <bruce.richardson@intel.com>; Wiles,
> Keith <keith.wiles@intel.com>
> Subject: Re: [dpdk-dev] doc: deprecation notice for ethdev ops?
> 
> On 2/13/2017 4:09 PM, Thomas Monjalon wrote:
> > 2017-02-13 16:02, Dumitrescu, Cristian:
> >> Hi Thomas,
> >>
> >> When a new member (function pointer) is added to struct eth_dev_ops
> (as the last member), does it need to go through ABI chance process (e.g.
> chance notice one release before)?
> >>
> >> IMO the answer is no: struct eth_dev_ops is marked as internal and its
> instances are only accessed through pointers, so the rte_eth_devices array
> should not be impacted by the ops structure expanding at its end. Unless
> there is something that I am missing?
> >
> > You are right, it is an internal struct.
> > So no need of a deprecation notice.
> 
> When dpdk compiled as dynamic library, application will load PMDs
> dynamically as plugin.
> Is this use case cause ABI compatibility issue?
> 
> I think drivers <--> libraries interface can cause ABI breakages for
> dynamic library case, although not sure how common use case this is.
> 

Do you have a specific example that might cause an issue when adding a new function at the end of the ethdev ops structure? I cannot think of any, given that the ops structure is marked as internal and it is only accessed through pointers.

> 
> >
> > We must clearly separate API and internal code in ethdev.
> >
> >> My question is in the context of this patch under review for 17.5 release:
> http://www.dpdk.org/ml/archives/dev/2017-February/057367.html.
> >
> > I did not look at it yet. Will do after the release.
> >
> >