Re: [RFC] virtio: use mandatory barriers for remote processor vdevs

From: Rusty Russell
Date: Wed Nov 30 2011 - 22:18:39 EST


On Thu, 1 Dec 2011 01:13:07 +0200, "Michael S. Tsirkin" <mst@xxxxxxxxxx> wrote:
> For x86, stores into memory are ordered. So I think that yes, smp_XXX
> can be selected at compile time.
>
> So let's forget the virtio strangeness for a minute,

Hmm, we got away with light barriers because we knew we were not
*really* talking to a device. But now with virtio-mmio, turns out we
are :)

I'm really tempted to revert d57ed95 for 3.2, and we can revisit this
optimization later if it proves worthwhile.

Thoughts?
Rusty.
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