Re: [Xen-ia64-devel] [PATCH][3/3] Steal time accounting forPVdomain/IA64 TAKE2

[Atsushi SAKAI <sakaia@xxxxxxxxxxxxxx>]

Hi, Isaku

  Thank you for commenting this.

1)about new_itm  value.
"new_itm" is set from local_cpu_data->itm_next
(later I use this as itm_next) 
at header part of timer_interrupt.

So it does not effect itm_next changes in
consider_steal_time().

2)The difference of following time 
> > > ia64_get_itc() - (the itc of the last time 
> > >                   the timer interrupt handler was invoked)

Every time should set next ITM like follows.
local_cpu_data->itm_next(itm_next)+local_cpu_data->itm_delta(itm_delta).

So "guessed last itc" should be itm_next - itm_delta
This itm_delta effect is already considered on stolentick++;

Thanks
Atsushi SAKAI



Isaku Yamahata <yamahata@xxxxxxxxxxxxx> wrote:

> On Fri, May 09, 2008 at 03:48:24PM +0900, Atsushi SAKAI wrote:
> 
> > Isaku Yamahata <yamahata@xxxxxxxxxxxxx> wrote:
> > 
> > > 
> > > >         do_div(stolentick, NS_PER_TICK);
> > > >         stolentick++;
> > > > 
> > > >         do_div(stolen, NS_PER_TICK);
> > > > 
> > > >         if (stolen > stolentick)
> > > >                 stolen = stolentick;
> > > > 
> > > >         stolentick -= stolen;
> > > >         do_div(blocked, NS_PER_TICK);
> > > > 
> > > >         if (blocked > stolentick)
> > > >                 blocked = stolentick;
> > > 
> > > Could you please explain the above logic?
> > > I guess that stolentick should be
> > > ia64_get_itc() - (the itc of the last time 
> > >                   the timer interrupt handler was invoked)
> > > or something like that.
> > 
> > your suggested value is new_itm.
> > That variable keeps as "local_cpu_data->itm_next" in the ia64 time code.
> 
> No. local_cpu_data->itm_next doesn't hold such value because
> the valuable is updated by consider_steal_time() so that the
> wanted value is lost.
> 
> -- 
> yamahata



_______________________________________________
Xen-ia64-devel mailing list
Xen-ia64-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-ia64-devel