Re: [Qemu-devel] [PATCH] Add a memory barrier to guest memory access functions

[Benjamin Herrenschmidt]

On Tue, 2012-05-22 at 01:44 +0300, Michael S. Tsirkin wrote:
> 
> OK. Just not another level of indirect function callbacks please.  Make
> it a library so each bus can do the right thing.  There are not so many
> buses. 

I think we are a long way from having to deal with subtly different
ordering rules, at this stage I'm keen on just sticking it in the inline
dma_ accessor, period.

We can always have flags in the dma context to indicate the sort of
ordering, avoids indirect pointer calls which can be costly (often
mispredicted).

Ben.