Re: [Qemu-devel] [PATCH 4/6] Handle CPU interrupts by inline checking of a flag

[Peter Maydell]

On 23 February 2013 10:03, Peter Maydell <address@hidden> wrote:
> On 22 February 2013 21:15, Paul Brook <address@hidden> wrote:
>>> @@ -100,6 +102,7 @@ struct CPUState {
>>>      bool stop;
>>>      bool stopped;
>>>      volatile sig_atomic_t exit_request;
>>> +    volatile sig_atomic_t tcg_exit_req;
>>
>> Do we really need annother variable/check?  It seems like this should be at
>> least partially redundant with the existing icount code. I have a simialr
>> patch to that effect.
>
> I wanted to keep the code simple and easy to review for correctness
> and obvious non-interaction with other features.

Also the icount check code does comparatively complicated operations
on the icount which would be awkward to make atomic or otherwise
safe against a signal handler or other thread coming in and
changing something.

-- PMM