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Subject: [Qemu-devel] Re: [RfC PATCH 08/11] spice: add qxl device
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To: Paolo Bonzini <pbonzini@redhat.com>
Cc: Blue Swirl <blauwirbel@gmail.com>, Gerd Hoffmann <kraxel@redhat.com>, qemu-devel@nongnu.org

On 04/16/2010 05:18 AM, Paolo Bonzini wrote:
>>> I'd just use __sync_fetch_and_or here.
>>
>> Good idea.  I think we can zap the memory barrier and fix a small race
>> while being at it, see the incremental fix below.
>
> Not sure about the memory barrier semantics of __sync_* (rth?), but
> besides that the patch seems like a good idea.
>

The semantics of __sync_*, with only 2 exceptions, is full barrier.


r~