Re: [PATCH V2 6/6] virtio-pci: implement dirty page tracking

["Zhu, Lingshan" <lingshan.zhu@intel.com>]

On 11/6/2023 7:21 PM, Parav Pandit wrote:
> > From: Michael S. Tsirkin <mst@redhat.com>
> > Sent: Monday, November 6, 2023 4:00 PM
> >
> > On Mon, Nov 06, 2023 at 04:34:44AM +0000, Parav Pandit wrote:
> > > > Do you know there are locked transaction and atomic operations in PCI???
> > > Can you explain how PCI does RMW locked transaction?
> > > Is it one TLP or multiple?
> > Parav what are you asking about here?
> > pcie supports CAS and Swap which likely
> > can work for this use-case - these are non posted writes. It's in the pcie spec.
> PCI spec do not have atomic OR operation.
> Lingshan in above comment suggested some unknown locked transaction and atomic operation.
> So I was asking him which is that atomic operation and how PCI does it?
> I don't know if any that can do PCI atomic OR without a workaround.
6.15 Atomic Operations (AtomicOps)