[PATCH v3 for-4.13 2/6] mlx5: move affinity hints assignments to generic code

[Sagi Grimberg]

>>> is there any reason you want to start assining vectors on the local
>>> node?  This is doable, but would complicate the code quite a bit
>>> so it needs a good argument.
>>
>>
>> My interpretation is that mlx5 tried to do this for the (rather esoteric
>> in my mind) case where the platform does not have enough vectors for the
>> driver to allocate percpu. In this case, the next best thing is to stay
>> as close to the device affinity as possible.
>>
> 
> No, we did it for the reason that mlx5e netdevice assumes that
> IRQ[0]..IRQ[#num_numa/#cpu_per_numa]
> are always bound to the numa close to the device. and the mlx5e driver
> choose those IRQs to spread
> the RSS hash only into them and never uses other IRQs/Cores

OK, that explains a lot of weirdness I've seen with mlx5e.

Can you explain why you're using only a single numa node for your RSS
table? What does it buy you? You open RX rings for _all_ cpus but
only spread on part of them? I must be missing something here...