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From: Anthony Liguori <anthony@codemonkey.ws>
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Date: Mon, 08 Oct 2012 15:53:37 -0500
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Subject: Re: [Qemu-devel] Building QEMU with multiple CPU targets.
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: "qemu-devel@nongnu.org Developers" <qemu-devel@nongnu.org>, Peter Crosthwaite <peter.crosthwaite@petalogix.com>, John Williams <john.williams@xilinx.com>, Paolo Bonzini <pbonzini@redhat.com>, "Edgar E. Iglesias" <edgar.iglesias@gmail.com>, Andreas =?utf-8?Q?F=C3=A4rber?= <afaerber@suse.de>

Peter Maydell <peter.maydell@linaro.org> writes:

> On 8 October 2012 21:23, Anthony Liguori <anthony@codemonkey.ws> wrote:
>> It may be possible to cheat and compile the TCG + CPU code multiple
>> times as dynamic libraries.  You can then load the libraries with
>> dlopen() with local symbol resolution.
>
> ...and when the common code wants to (say) call cpu_exit() on a
> particular core, how does it know which DLL's version to call?
> That said, I have a feeling I've heard about people trying this
> kind of approach before, so it's probably possible to get something
> that works on at least one host OS. I think doing it "properly"
> would be less of a hack, though...

I think you basically need to treat a "foreign" CPU separately from a
local CPU.  You would load foreign CPUs as libraries and interact with
it separately.

I think the initial focus should be on hacking something to work.  Then
we can figure out what's the best path to merging.

Regards,

Anthony Liguori

>
> -- PMM