Re: [Qemu-devel] [PATCH v3 6/6] vhost-user: support registering external host notifiers

[Paolo Bonzini]

On 19/04/2018 17:42, Michael S. Tsirkin wrote:
>> A compiler barrier is enough on strongly-ordered memory platform.
>> As it doesn't re-order store, PCI device won't see a stale index
>> value. But a weakly-ordered memory needs sfence.
> 
> Oh you are right.
> 
> So it's only needed for non-intel platforms or when packets are in
> WC memory then. And I don't know whether dpdk ever puts packets in WC
> memory.
> 
> I guess we'll cross this bridge when we get to it.

Non-TSO architectures seem important...

Paolo