Re: [PATCH 09/25] xen: Account for time stolen by Xen

On Wednesday 25 April 2007 20:13:34 Jeremy Fitzhardinge wrote:
> Andi Kleen wrote:
> >> +
> >> +	do {
> >> +		state_time = state->state_entry_time;
> >> +		barrier();
> >>     
> >
> > Should be likely rmb
> 
> We discussed this, and decided that it wasn't necessary.  The state is
> always updated by the current CPU, so if it changes under our feet it
> will be because we were preempted, and so that should shoot down any
> speculated reads.

Then the barrier shouldn't be needed at all? 

Anyways needs comments

-Andi
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Follow-Ups:
- Re: [PATCH 09/25] xen: Account for time stolen by Xen
  - From: Jeremy Fitzhardinge <[email protected]>

References:
- [PATCH 00/25] xen: Xen implementation for paravirt_ops
  - From: Jeremy Fitzhardinge <[email protected]>
- Re: [PATCH 09/25] xen: Account for time stolen by Xen
  - From: Andi Kleen <[email protected]>
- Re: [PATCH 09/25] xen: Account for time stolen by Xen
  - From: Jeremy Fitzhardinge <[email protected]>

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