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

[Peter Maydell]

On 17 December 2014 at 16:29, Mark Burton <address@hidden> wrote:
>> On 17 Dec 2014, at 17:27, Peter Maydell <address@hidden> wrote:
>> I think a mutex is fine, personally -- I just don't want
>> to see fifteen hand-hacked mutexes in the target-* code.
>>
>
> Which would seem to favour the helper function approach?
> Or am I missing something?

You need at least some support from QEMU core -- consider
what happens with this patch if the ldrex takes a data
abort, for instance.

And if you need the "stop all other CPUs while I do this"
semantics linux-user currently uses then that definitely needs
core code support. (Maybe linux-user is being over-zealous
there; I haven't thought about it.)

-- PMM