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Date: Wed, 10 Jul 2013 13:42:53 +0300
From: Gleb Natapov <gleb@redhat.com>
To: Alexander Graf <agraf@suse.de>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>,
        Dominik Dingel <dingel@linux.vnet.ibm.com>,
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On Wed, Jul 10, 2013 at 12:39:01PM +0200, Alexander Graf wrote:
> 
> On 09.07.2013, at 18:01, Christian Borntraeger wrote:
> 
> > On 09/07/13 15:56, Dominik Dingel wrote:
> >> By setting a Kconfig option, the architecture can control when
> >> guest notifications will be presented by the apf backend.
> >> So there is the default batch mechanism, working as before, where the vcpu thread
> >> should pull in this information. On the other hand there is now the direct
> >> mechanism, this will directly push the information to the guest.
> >> 
> >> Still the vcpu thread should call check_completion to cleanup leftovers,
> >> that leaves most of the common code untouched.
> >> 
> >> Signed-off-by: Dominik Dingel <dingel@linux.vnet.ibm.com>
> > 
> > Acked-by: Christian Borntraeger <borntraeger@de.ibm.com> 
> > for the "why". We want to use the existing architectured interface.
> 
> Shouldn't this be a runtime option?
> 
Why? What is the advantage of using sync delivery when HW can do it
async?

--
			Gleb.