Re: [Qemu-devel] [RFC][PATCH 28/45] qemu-kvm: msix: Drop tracking of used vectors

[Michael S. Tsirkin]

On Fri, Oct 21, 2011 at 09:09:10AM +0200, Jan Kiszka wrote:
> On 2011-10-21 00:02, Michael S. Tsirkin wrote:
> >>> Yes. But this still makes an API for acquiring per-vector resources a 
> >>> requirement.
> >>
> >> Yes, but a different one than current use/unuse.
> > 
> > What's wrong with use/unuse as an API? It's already in place
> > and virtio calls it.
> 
> Not for that purpose.
> It remains a useless API in the absence of KVM's
> requirements.
> 

Sorry, I don't understand. This can acquire whatever resources
necessary. It does not seem to make sense to rip it out
only to add a different one back in.

> > 
> >> And it will be an
> >> optional one, only for those devices that need to establish irq/eventfd
> >> channels.
> >>
> >> Jan
> > 
> > Not sure this should be up to the device.
> 
> The device provides the fd. At least it acquires and associates it.
> 
> Jan

It would surely be beneficial to be able to have a uniform
API so that devices don't need to be recoded to be moved
in this way.

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