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Date: Wed, 07 Dec 2011 22:16:51 +0530
From: Raghavendra K T <raghukt@linux.vnet.ibm.com>
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To: Avi Kivity <avi@redhat.com>
CC: Marcelo Tosatti <mtosatti@redhat.com>,
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Subject: Re: [PATCH RFC V3 2/4] kvm hypervisor : Add a hypercall to KVM hypervisor
 to support pv-ticketlocks
References: <20111130085921.23386.89708.sendpatchset@oc5400248562.ibm.com> <20111130085959.23386.69166.sendpatchset@oc5400248562.ibm.com> <20111207104849.GA24849@amt.cnet> <4EDF5413.1030107@linux.vnet.ibm.com> <20111207123330.GA32212@amt.cnet> <4EDF6049.2030204@redhat.com> <20111207133947.GA1708@amt.cnet> <4EDF7DC5.5010504@redhat.com>
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On 12/07/2011 08:22 PM, Avi Kivity wrote:
> On 12/07/2011 03:39 PM, Marcelo Tosatti wrote:
>>> Also I think we can keep the kicked flag in vcpu->requests, no need for
>>> new storage.
>>
>> Was going to suggest it but it violates the currently organized
>> processing of entries at the beginning of vcpu_enter_guest.
>>
>> That is, this "kicked" flag is different enough from vcpu->requests
>> processing that a separate variable seems worthwhile (even more
>> different with convertion to MP_STATE at KVM_GET_MP_STATE).
>
> IMO, it's similar to KVM_REQ_EVENT (which can also cause mpstate to
> change due to apic re-evaluation).
>

Ok, So what I understand is we have to either :
1. retain current kick flag AS-IS but would have to make it migration 
friendly. [I still have to get more familiar with migration side]
or
2. introduce notion similar to KVM_REQ_PVLOCK_KICK(??) to be part of
vcpu->requests.

So what would be better? Please let me know.