Re: [Qemu-devel] Re: TCG flow vs dyngen

[Lluís]

Stefano Bonifazi writes:

> Now, the final goal is to get multiple instances of qemu-ppc driven by a 
> systemc
> project executing on a x86 machine, with the different qemu-ppc instances used
> as emulators for power-pc binaries.. I would get the results of the run of the
> various ppc binaries back to the systemc project and work with the results 
> then.

If I understand this correctly, the execution of one of your PPC cores
is oblivious of the others (they share no guest physical memory).

If that's true, it would be extremely more simple to make systemc launch
a separate process with a modified version of linux-user. This modified
version would just change the main loop in a way that it can communicate
with systemc, e.g., using shared memory.

Of course, depending on the granularity of synchronization that you
want, this might not prove useful: if systemc and the linux-user
processes all execute in the finest possible synchronization (e.g.,
comunicate after each TB or even after each instruction), the
communication overhead might prove too high.

Still, if you want a somewhat looser synchronization, you could take a
look at how COTSon [1] does it.


[1] http://sites.google.com/site/hplabscotson/

Lluis

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