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

From
Michael S. Tsirkin <>
Date
2018-04-19T16:35:15+00:00
ID
Thread
Re: [PATCH v3 6/6] vhost-user: support registering external host notifiers
On Thu, Apr 19, 2018 at 05:52:23PM +0200, Paolo Bonzini wrote:
> 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

Only if there are virtio offload engines on platforms with these
architectures :) Worth working on for sure but doesn't have to block
this patchset.

-- 
MST