Re: [PATCH] tsc: use kvmclock for calibration

[Avi Kivity <avi@redhat.com>]

On 08/09/2012 09:59 PM, Marcelo Tosatti wrote:
>> 
>> > +    wrmsr(msr, 0);
>> > +    if (time.version < 2 || time.tsc_to_system_mul == 0)
>> > +        return 0;
>> > +
>> > +    /* go figure tsc frequency */
>> > +    khz = pvclock_tsc_khz(&time);
>> > +    dprintf(1, "Using kvmclock, msr 0x%x, tsc %d MHz\n",
>> > +            msr, (u32)khz / 1000);
>> > +    return khz;
>> 
>> That's a meaningless number.  You can be migrated to a cpu or a machine
>> with very different tsc.
> 
> Thats why there exists hardware tsc frequency scaling and the software
> equivalent for that on kvm.
> 

The hardware is only available on a minority of processors in the field.
 The software equivalent isn't there.

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