Re: [PATCH RFC 1/2] kvm: Handle undercommitted guest case in PLEhandler

From: Avi Kivity
Date: Wed Oct 03 2012 - 11:01:28 EST


On 10/03/2012 04:17 PM, Raghavendra K T wrote:
> * Avi Kivity <avi@xxxxxxxxxx> [2012-09-30 13:13:09]:
>
>> On 09/30/2012 01:07 PM, Gleb Natapov wrote:
>> > On Sun, Sep 30, 2012 at 10:18:17AM +0200, Avi Kivity wrote:
>> >> On 09/28/2012 08:16 AM, Raghavendra K T wrote:
>> >> >
>> >> >>
>> >> >> +struct pv_sched_info {
>> >> >> + unsigned long sched_bitmap;
>> >> >
>> >> > Thinking, whether we need something similar to cpumask here?
>> >> > Only thing is we are representing guest (v)cpumask.
>> >> >
>> >>
>> >> DECLARE_BITMAP(sched_bitmap, KVM_MAX_VCPUS)
>> >>
>> > vcpu_id can be greater than KVM_MAX_VCPUS.
>>
>> Use the index into the vcpu table as the bitmap index then. In fact
>> it's better because then the lookup to get the vcpu pointer is trivial.
>
> Did you mean, while setting the bitmap,
>
> we should do
> for (i = 1..n)
> if (kvm->vcpus[i] == vcpu) set ith position in bitmap?

You can store i in the vcpu itself:

set_bit(vcpu->index, &kvm->preempted);

>
> I just wanted to know whether there is any easy way to convert from
> vcpu pointer to index in kvm vcpu table.
>



--
error compiling committee.c: too many arguments to function
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