Re: [dpdk-users] How L2 broadcast is handled under rte_flow?

[Hideyuki Yamashita <yamashita.hideyuki@ntt-tx.co.jp>]

Hello Experts,

Can somebody help me?
(Or many people still enjoy summer vacation?)

I think it is very interesting question
how NIC handles L2 broadcast when multiple queues are setup.

Or are there any way(DPDK API) to set NIC to assign all rx queues
when receiving L2 broadcast?

Thanks in advance.
BR,
Hideyuki Yamashita
NTT TechnoCross


> Hello Experts,
> 
> I have basic questions on how L2 broadcast is handled under rte_flow.
> 
> [Question1]
> 
> To which queue L2 broadcast packet will be received?
> 
> testpmd> flow create 0 ingress pattern eth dst is 11:22:33:44:55:66 type mask 0xffff / end actions queue index 1 / end
> testpmd> flow create 0 ingress pattern eth dst is 22:33:44:55:66:77 type mask 0xffff / end actions queue index 2 / end
> 
> My expectation is both queue 1 and queue 2 receive broadcast(dst MAC is
> FF:FF:FF:FF:FF:FF).
> Or only default queue (queue 0 ) receive the packet?
> 
> If we assume NIC act as switching hub and queues are ports,
> broadcast packets will be flooded to all available ports.
> Let us assume the situation that there exists software switch
> which act like switching hub (deliver packets based on dst MAC),
> and I want the function offload to NIC via rte_flow.
> 
> [Question2]
> What happens if VLAN is involved?
> 
> My expectation is as following:
> If receive broadcast packet (dst is FF:FF:FF:FF:FF:FF) for specific vlan,
> all queues related to this vlan id will receive the broadcast packet.
> Is my understanding correct?
> 
> It may depends on each rte_flow implementations.
> But if there is a rule in common among various NICs, I want to know.