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To: "Hunt, David" <david.hunt@intel.com>,
 Thomas Monjalon <thomas.monjalon@6wind.com>,
 "Wiles, Keith" <keith.wiles@intel.com>
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From: Olivier MATZ <olivier.matz@6wind.com>
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Date: Mon, 15 Feb 2016 11:15:22 +0100
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Cc: dev@dpdk.org
Subject: Re: [dpdk-dev] [PATCH v3] mempool: reduce rte_mempool structure size
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Hi David,

On 02/15/2016 10:58 AM, Hunt, David wrote:
> On 12/02/2016 15:50, Olivier MATZ wrote:
>> - NEXT_ABI does make the code harder to read in this case, and I'm
>>    thinking about the patchset from David Hunt (external mempool handler)
>>    that will be in the same situation, and maybe also another patchset
>>    I'm working on.
> 
> Olivier,
>     I'm working on that at the moment with the external mempool handler
> code. However, it crossed my mind that we have a choice to use symbol
> versioning OR use NEXT_ABI. Would one method be preferred over the other?

I think symbol versioning should always be preferred when possible.

In your case, as far as I remember, your are updating the rte_mempool
structure, which is accessed by static inline functions. I don't think
it is easily manageable with symbol versioning. Moreover, the ABI will
already be broken by Keith's patch, so I think it's less problematic
to have other patches breaking the ABI at the same time.

Regards,
Olivier