Re: [Qemu-devel] [RFC v2 08/11] tcg: add options for enabling MTTCG

[Alex Bennée]

Pavel Dovgalyuk <address@hidden> writes:

>> From: address@hidden [mailto:address@hidden
>> On 12/04/16 15:50, KONRAD Frederic wrote:
>> >> Yes, but users may like to have an option to disable MTTCG for some
>> >> reason. I'm also concerned about icount mode: not sure how to account
>> >> virtual time when all vCPUs run in parallel.
>> >
>> > I'm thinking the same, we don't have a solution for icount yet.
>> > The reverse execution support is probably badly broken as well.
>>
>> Reverse execution doesn't even seem to support more than a single core.
>> As of icount, it looks like to be incompatible with MTTCG.
>
> It doesn't, because there is no multicore support for tcg yet.
> I think, that we have to find some solution for icount (even if it
> will be slow).

Well one of the reasons I'm keeping single thread behaviour is so things
like icount/replay support can continue to work. The two options will be
incompatible to start with.

I'm also expecting people will want to rule out mttcg as a problem at
least in the early days.

--
Alex Bennée