Re: [PATCH kvm-unit-tests 2/4] Introduce a C++ wrapper for the kvm APIs

[Anthony Liguori <anthony@codemonkey.ws>]

On 11/24/2010 06:59 AM, Alexander Graf wrote:
> On 24.11.2010, at 11:52, Avi Kivity wrote:
>
>    
>> Introduce exception-safe objects for calling system, vm, and vcpu ioctls.
>>
>> Signed-off-by: Avi Kivity<avi@redhat.com>
>>      
>
> FWIW, I still disagree with C++ and believe this code to be hardly readable.
>    

Take a look at http://repo.or.cz/w/qemupp.git

Start with test/test-mc146818a.cpp

This test infrastructure is arguably a bad place to start because it 
doesn't benefit really at all from C++.  The object hierarchy is 
extremely simple and most of the time you're interfacing with legacy C 
interfaces so a lot of effort is spent bridging those interfaces.

OTOH, the device models interact very little with the external world and 
the object model is complex is subtle ways.  I think C++ is a much 
better fit there.

In the above repo, I've converted the PIT, RTC, keyboard controller, and 
have started working on the i440fx.  The i440fx is a lot of work but 
it's also one of the more interesting devices to try and model correctly.

For all devices, there are very intensive unit tests that use fuzzing.  
I hope to have something postable for serious consideration by the end 
of the year.

BTW, given the ability to test programmatically, I ended up rewriting a 
good bit of the PIT and RTC.  The way that the unit conversion is 
handled right now in QEMU is a train wreck.  The new version is much 
more accurate and as a consequence, the interrupt catch up logic is much 
more precise.  There are also three different catch up algorithms that 
are selectable at run time.

This is all tested with a time simulation that can simulate random 
amounts of drift over random periods of time.

Regards,

Anthony Liguori

>
> Alex
>
>
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