Re: [dpdk-dev] [PATCH] cryptodev: version rte_cryptodev_info_get function

[Ray Kinsella <mdr@ashroe.eu>]

On 17/04/2020 11:17, Thomas Monjalon wrote:
> 17/04/2020 11:42, Ray Kinsella:
>> On 17/04/2020 10:31, Bruce Richardson wrote:
>>> On Fri, Apr 17, 2020 at 08:24:30AM +0100, Ray Kinsella wrote:
>>>> On 16/04/2020 11:01, Thomas Monjalon wrote:
>>>>> 16/04/2020 11:51, Bruce Richardson:
>>>>>> On Wed, Apr 15, 2020 at 06:24:19PM +0100, Trahe, Fiona wrote:
>>>>>>> 5a. If in 20.05 we add a version of a fn which breaks ABI 20.0, what should the name of the original function be? fn_v20, or fn_v20.0
>>>>>>
>>>>>> In technical terms it really doesn't matter, it's just a name that will be
>>>>>> looked up in a table. I don't think we strictly enforce the naming, so
>>>>>> whatever is clearest is best. I'd suggest the former.
>>>>>
>>>>> Each release can have a new ABI.
>>>>
>>>> How many ABI's do we want to support?
>>>>
>>> It's not how many we want to support, but for me it's a matter of how many
>>> do we need to support. If an API is part of the stable set, it can't just
>>> drop to being experimental for one or two releases - it's always stable
>>> until deprecated. We also shouldn't have a situation where release 20.08 is
>>> ABI compatible with 19.11 but not 20.02 and 20.05.
>>
>> True. Let me say it differently.
>>
>> Our only commitment is to support v20 - 19.11
>> However you are correct, if something gets committed as v21 in 20.02, in practise should also be there in 20.05+ also.
>> Because if it is committed as v21 and not as experimental, it should not be changing once committed.  
>>
>> In answering Thomas, 
>> I was more commenting on the proliferation of ABI numbers & symbols we need to track in the build.
>> With v20, v21 & Experimental we need to keep track of 3.
>> If we start allowing quarterly builds to have managed ABI's, it will get confusing. 
> 
> I don't remember why we are using intermediate ABI versions
> between v20 and v21.
> If we can use v21 for new ABI and make sure compatibility is maintained
> between all versions from 19.11 to 20.08, I'm fine.
> 

Well I guess we missed this in 20.02, so I recommend that we fix in 20.05.

It will mean that a couple of symbols versioned 20.0.2 in DPDK 20.02, 
Will becomes 21.0 in DPDK 20.05 ... ABI checker will complain.

Apart from that I doubt anyone will notice?

Ray K