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From: Paolo Bonzini <pbonzini@redhat.com>
To: Francois WELLENREITER <francois.wellenreiter@bull.net>
Cc: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] PCI CAS implementation in qemu
Date: Tue, 20 Nov 2012 17:48:18 +0100	[thread overview]
Message-ID: <50ABB452.4070401@redhat.com> (raw)
In-Reply-To: <50ABB0A4.9030600@bull.net>

Il 20/11/2012 17:32, Francois WELLENREITER ha scritto:
> 
> I order to develop a qemu module, I aim to use the PCI CAS (compare
> and swap) function to guarantee an atomic access somewhere in the
> guest memory (in a multi-core emulation case).
> 
> Nevertheless, I did not find any routine in qemu implementing this
> function.
> 
> Could anyone on this list tell me if this is implemented and if that's
> not the case, if this would be hard to get implemented ?

(I know nothing about PCI CAS).

Can you just use a compare-and-swap in the QEMU device model (via
__sync_val_compare_and_swap for example)?

Paolo

      reply	other threads:[~2012-11-20 16:48 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-11-20 16:32 [Qemu-devel] PCI CAS implementation in qemu Francois WELLENREITER
2012-11-20 16:48 ` Paolo Bonzini [this message]

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