Re: [Xen-devel] [PATCH RFC V5 2/6] kvm hypervisor : Add a hypercall to KVM hypervisor to support pv-ticketlocks

[Raghavendra K T <raghavendra.kt@xxxxxxxxxxxxxxxxxx>]

On 04/12/2012 05:59 AM, Marcelo Tosatti wrote:
> On Wed, Apr 11, 2012 at 09:06:29PM -0300, Marcelo Tosatti wrote:
> > On Fri, Mar 23, 2012 at 01:37:04PM +0530, Raghavendra K T wrote:
> > > From: Srivatsa Vaddagiri<vatsa@xxxxxxxxxxxxxxxxxx>
[...]

                barrier();
> > Is it always OK to erase the notification, even in case an unrelated
> > event such as interrupt was the source of wakeup?
> Note i am only asking whether it is OK to lose a notification, not
> requesting a change to atomic test-and-clear.
Yes.. got your point.
IMO, this is the only (safe) place where it can clear
kicked(pv_unhalted) flag. Since it is going to be runnable.

and you are also right in having concern on unwanted clear of flag
since that would result in vcpu /vm hangs eventually.

Hope I did not miss anything.

> It would be nice to have a comment explaining it.
Sure will do that

> >

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