Re: [PATCH 2 of 2 RFC] xen, pod: Only sweep in an emergency, and only for 4k pages

[George Dunlap <George.Dunlap@eu.citrix.com>]

[re-including xen-devel in the cc]]

On Thu, Jun 14, 2012 at 2:13 PM, Tim Deegan <tim@xen.org> wrote:
> At 13:42 +0100 on 14 Jun (1339681375), George Dunlap wrote:
>> On Thu, Jun 14, 2012 at 10:11 AM, Tim Deegan <tim@xen.org> wrote:
>> > At 11:45 +0000 on 08 Jun (1339155933), George Dunlap wrote:
>> >> +    if ( p2m->pod.count == 0 )
>> >> +        goto out_of_memory;
>> >>
>> >>      /* Keep track of the highest gfn demand-populated by a guest fault */
>> >>      if ( gfn > p2m->pod.max_guest )
>> >>          p2m->pod.max_guest = gfn;
>> >>
>> >> -    if ( p2m->pod.count == 0 )
>> >> -        goto out_of_memory;
>> >> -
>> >
>> > Is this code motion just noise?  Since out_of_memory crasheds the guest,
>> > I assume so.
>>
>> It will have no practical effect, other than improving the efficiency
>> of crashing a guest by a few cycles, if that's what you're asking.
>> It's more about taste: it just seemed silly to make an assignment and
>> *then* see if you were going to crash. :-)
>
> Well, yes. :)  I don't think it quite falls under the description of the
> patch, though.  Can you split it out as a cleanup patch?

If that's what you meant, you should have said so. :-)  I shall do so
for the next series.

 -George