Re: [Qemu-devel] [PULL 42/43] piix4: add acpi pci hotplug support

[Gleb Natapov]

On Thu, Oct 17, 2013 at 08:32:14AM +0300, Michael S. Tsirkin wrote:
> On Thu, Oct 17, 2013 at 12:25:32AM +0200, Paolo Bonzini wrote:
> > Il 17/10/2013 00:03, Michael S. Tsirkin ha scritto:
> > > On Wed, Oct 16, 2013 at 11:26:11PM +0200, Paolo Bonzini wrote:
> > >> Il 16/10/2013 20:37, Michael S. Tsirkin ha scritto:
> > >>> Gleb, Paolo, what do you think? OK to merge kvm unit test
> > >>> into qemu? It depends on qemu anyway, in-tree will make it easier.
> > >>> Maybe someone's looking at this already?
> > >>
> > >> I think merging KVM unit tests doesn't make much sense because, with
> > >> some small exceptions, it is mostly a test or a benchmark for KVM.
> > > 
> > > But why keep them separate? They need qemu to work, don't they?
> > 
> > Not necessarily.  They need a userspace component of course, but most of
> > them do not need something as big as QEMU.  Most tests, perhaps all,
> > only write to a handful of ports and use no BIOS services.
> 
> Well all of them use the test device to report status, right?
> Do they work on e.g. kvmtool?
> If anyone uses these tests outside QEMU then maybe it's
> worth it to be nice and keep it separate.
> If not it's just extra pain and compatibility worries without
> any real gain - and if someone starts using it
> this way down the line we'll be able to use something
> like git subtree to extract it again.
> 
Same logic can be used to argue that unittest should be part of Linux
tree. Unittest was part of qemu-kvm and it was decided that having
separate repository for it is much better. Time showed that this is
true. Look at unittests commits and see how much of them have something
to do with QEMU changes and how much do not, and now look at the same
commit and see how much of them has something to do with kernel. See? The
argument for putting unittest into kernel repo is much stronger.

> For example I think it might be nice to switch everyone
> to use pci device instead of fixed ports - less magic
> numbers this way. But if I need to keep it working on
> old qemu and keep two versions of code around, I'd
> probably not bother.
> 
Nothing nice about it. Test device is all about simplicity. If separate
repository stops one from even attempting it the separation was already
a win :)

--
                        Gleb.