From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sasha Levin <levinsasha928@gmail.com>
Subject: Re: ioeventfd question
Date: Fri, 27 May 2011 11:39:37 +0300
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References: <1306436620.3065.43.camel@lappy>  <4DDF6118.9030103@redhat.com>
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Cc: kvm <kvm@vger.kernel.org>, Ingo Molnar <mingo@elte.hu>,
	Pekka Enberg <penberg@kernel.org>,
	Asias He <asias.hejun@gmail.com>,
	Prasad Joshi <prasadjoshi124@gmail.com>,
	Cyrill Gorcunov <gorcunov@gmail.com>
To: Avi Kivity <avi@redhat.com>
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On Fri, 2011-05-27 at 11:30 +0300, Avi Kivity wrote:
> On 05/26/2011 10:03 PM, Sasha Levin wrote:
> > Hi Avi,
> >
> > I'm working on adding ioeventfd support into tools/kvm/.
> > Currently the implementation creates ioeventfd entries at the
> > 'VIRTIO_PCI_QUEUE_NOTIFY' of each device and waits on all of them using
> > epoll().
> > The basics are working - when IO is triggered I receive a notification
> > using the event instead of an exit.
> >
> > I couldn't find a way to retrieve the value written to the PIO port -
> > the guest memory at that location doesn't change, 'reading' the event
> > just returns 1 (as expected) and I couldn't find anything else which
> > might suggest what value was written to the PIO port.
> 
> You can use KVM_IOEVENTFD_FLAG_DATAMATCH for that.
> 

Oh, so I need to create one for each vq instead of one for each device.

Thanks!

-- 

Sasha.