Re: [PATCH] MMIO: Make coalesced mmio use a device per zone

[Avi Kivity <avi@redhat.com>]

On 07/19/2011 08:14 PM, Jan Kiszka wrote:
>
> Another improvement - unfortunately less transparent for user space -
> would be to overcome the single ring buffer that forces us to hold a
> central lock in user space while processing the entries. We rather need
> per-device rings. While waiting for coalesced VGA MMIO being processed,
> way too many kittens are killed.
>
> I have this on our agenda, but I wouldn't be disappointed as well if
> someone else is faster.

The socket mmio would have accomplished this as well.  One thing to 
beware of is to preserve correctness:

1) write to 0xa0000 (queued)
2) write to 0xa0002 (queued)
3) remap 0xa0000 region (executed)
4) write to 0xa000 (queued)
5) drain queue

writes 1 and 2 go to the wrong place.

-- 
error compiling committee.c: too many arguments to function