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Subject: Re: Question about naive XOR hash in DPDK
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To: Bili Dong <qobilidop@gmail.com>, dev@dpdk.org
Cc: cristian.dumitrescu@intel.com
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On 2022-11-07 19:57, Bili Dong wrote:
> Dear DPDK devs,
> 
> We are using DPDK as the backend target of a P4 pipeline 
> (https://github.com/p4lang/p4-dpdk-target 
> <https://github.com/p4lang/p4-dpdk-target>). A recent issue we are 
> trying to solve is to support a naive XOR hash (something like this 
> <https://github.com/p4lang/behavioral-model/blob/b7a5c105e5c21414ac07f7f2879b45c000ab2aa4/src/bm_sim/calculations.cpp#L380-L399>) in this pipeline. This requires an XOR hash implementation in DPDK.I have the following questions:


Why would it *require* an xor hash function in DPDK?

> 
>  1. Is there already an XOR hash implementation in DPDK? I haven't found
>     it myself, but I could have missed it.
>  2. If it doesn't exist, I'm willing to contribute one, as the
>     implementation is quite straightforward. But I might need your help
>     on where to put the code, as I'm not that familiar with the code
>     organization.
> 
> Any help would be appreciated!
> 
> Thanks,
> Bili
>