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Subject: Re: [Qemu-devel]
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To: Laurent Desnogues <laurent.desnogues@gmail.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, =?UTF-8?B?6Kej5aOB5Lyf?= <xiebiwei@ict.ac.cn>, qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@gmail.com>

Il 13/03/2013 10:56, Laurent Desnogues ha scritto:
>> > There has been some other research work with QEMU in this
>> > area, you should probably look it up. However it has all been
>> > "we fixed enough of the big problems to be able to run some
>> > benchmarks and write our research paper", so none of this is
>> > actually in the QEMU sources. (The short answer I think is
>> > "probably but it will depend a lot on workload, and there's
>> > a lot of software engineering required to do it reliably".)
> I know of two such variants: COREMU and HQEMU, but as far
> as I know the latter isn't freely available.

COREMU had one code generator per VCPU, if I remember correctly.

Jan Kiszka also posted an RFC patch that removed the "lockstep" behavior
of TCG, where the VCPU will always block the iothread even when it is
not executing MMIO.  Getting this upstream would be an even bigger step
than making the code generator thread-safe.

Paolo