[Xen-ia64-devel] RE: [PATCH 24/29] ia64/pv_ops/xen: implement xen pv_time_ops.

["Luck, Tony" <tony.luck@xxxxxxxxx>]

>+       if (!time_after(delta_itm + new_itm, ia64_get_itc()))
>+               stolentick = ia64_get_itc() - new_itm;
>+
>+       do_div(stolentick, NS_PER_TICK);
>
>
> Which makes me assume that ia64_get_itc() is returning nanoseconds; does
> it do the adjustment from the itc's actual rate to nanoseconds?  Could
> it also apply an offset?

No. ia64_get_itc() does no scaling it returns the raw value from
the cr.itc register which increments at a frequency that the OS
discovers using a PAL call.

I'm not quite sure what the above code thinks it is doing. NS_PER_TICK
may have been poorly named???

-Tony

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