Re: ethdev: hide internal structures

[Tyler Retzlaff <roretzla@linux.microsoft.com>]

On Tue, Nov 16, 2021 at 09:32:15AM +0000, Ferruh Yigit wrote:
> 
> Hi Tyler,
> 
> It shouldn't be an API change, which API is changed?

exported declarations that were consumed by the application were removed
from an installed header. anything making reference to rte_eth_devices[]
will no longer compile.

any change that removes any identifier or macro visible to the application
from an installed header is an api break.

> Existing binaries won't run and needs recompile, but shouldn't need to change
> the code.
> Unless application is accessing *internal* DPDK structs (which were exposed
> to application because of some technical issues that above commit fixes).

the application was, but the access was to a symbol and identifier that
had not been previously marked __rte_internal or __rte_experimental and thus
assumed to be public.

just to be clear i agree with the change making these internal but there
was virtually no warning.

https://doc.dpdk.org/guides-19.11/contributing/abi_policy.html

the exports and declarations need to be marked deprecated to give ample
time before being removed in accordance with the abi policy.

i will ask that work be scheduled to identify the gap in the public api
surface that access to these structures was providing rather than
backing the change out. fortunately it is only schedule rather
than service impacting since the application hadn't been deployed yet.

i thought someone was responsible for reviewing abi/api related changes
on the board to understand the implications of changes like this?

thanks