Re: [Qemu-devel] [RFC PATCH] target-arm: protect cpu_exclusive_*.

[Frederic Konrad]

On 16/12/2014 17:37, Peter Maydell wrote:
> On 16 December 2014 at 09:13,  <address@hidden> wrote:
> > From: KONRAD Frederic <address@hidden>
> >
> > This adds a lock to avoid multiple exclusive access at the same time in case of
> > TCG multithread.
Hi Peter,

> This feels to me like it's not really possible to review on
> its own, since you can't see how it fits into the design of
> the rest of the multithreading support.
true the only thing we observe is that it didn't change anything right now.

> The other approach here rather than having a pile of mutexes
> in the target-* code would be to have TCG IR support for
> "begin critical section"/"end critical section". Then you
> could have the main loop ensure that no other CPU is running
> at the same time as the critical-section code. (linux-user
> already has an ad-hoc implementation of this for the
> exclusives.)
>
> -- PMM
What do you mean by TCG IR?

Thanks,
Fred