[PATCH v3] net/af_xdp: re-enable secondary process support

[Ferruh Yigit]

On 2/8/2022 5:45 PM, Stephen Hemminger wrote:
> On Tue,  8 Feb 2022 13:48:00 +0000
> Ciara Loftus <ciara.loftus at intel.com> wrote:
> 
>> +- **Secondary Processes**
>> +
>> +  Rx and Tx are not supported for secondary processes due to the single-producer
>> +  single-consumer nature of the AF_XDP rings. However other operations including
>> +  statistics retrieval are permitted.
>> +  The maximum number of queues permitted for PMDs operating in this model is 8
>> +  as this is the maximum number of fds that can be sent through the IPC APIs as
>> +  defined by RTE_MP_MAX_FD_NUM.
>> +
> 
> This seems like a restriction that is true for most devices in DPDK.
> Most other devices also have restriction that on queues;
> the hardware descriptor ring can only be used by one thread at a time.
> Is this different with AF_XDP?

I asked the same on v2 :) and Ciara explained the reason, it is on v2 discussion thread.