Re: [Qemu-devel] Adding SMP support for Sparc Target

["Alex Bennée" <alex.bennee@linaro.org>]

Artyom Tarasenko <atar4qemu@gmail.com> writes:

> Hello Damien,
>
> On Thu, Nov 6, 2014 at 8:38 AM, Damien Hilloulin
> <damien.hilloulin@epfl.ch> wrote:
>> Hello everyone,
>>
>> I'm a newcomer in QEMU and my goal would be to port an existing system
>> simulator using another emulator to QEMU.
<snip>
>> However, it seems that the Sparc targets doesn't really support SMP/CMT as
>> of now. So I am considering two possibilities:
>> - adding SMP support in QEMU for the Sparc targets (and contribute it to
>> QEMU :) )
>
> Do you mean a) emulating multiple guest cores on in a single host
> thread, or b) emulating multiple guest cores in multiple host threads?
<snip>
> If you mean b), things get more complicated because TCG can currently
> utilize just one host thread. There was an attempt to do utilize
> multiple threads for an ARM target:
> http://sourceforge.net/p/coremu/home/Home
>
> It would be interesting to hear what the TCG experts would say. Adding
> Richard to CC.

There is a desire to fix this but a distinct lack of cycles. It's not a
small job and will require quite a bit of preparatory work to map out an
approach and then fix it.

Having said that I'm sure someone mentioned they had done some work on
this on one of the KVM conference calls. Unfortunately I didn't catch
their names as my phone kept dumping me of the call. Does anyone
remember who that was? 

-- 
Alex Bennée