RE: [Xen-ia64-devel]PATCH] Remove duplicate check is_running_on_xen

["Xu, Anthony" <anthony.xu@xxxxxxxxx>]

Alex Williamson write on 2007年1月17日 11:10:
> On Wed, 2007-01-17 at 10:17 +0800, Xu, Anthony wrote:
> 
>> There are two duplicate checks as below, so there are two way to
>> eliminate one check. 
>> 
>> 1. eliminate check in xen_get_tpr, then xen_get_tpr will never be
>>      called on bare metal, but it's a little perfomance impact, due
>> to there is another switch inside __ia64_getreg. 
>> 
>> 2. eliminate check in xen_ia64_getreg, then xen_get_tpr will be
>>    called both on para platform or bare metal, it can produce better
>> performance than option 1. so I prefer this. 
> 
>    Is the performance difference actually measurable?  I suspect it's
> effectively within the noise of any benchmark.  I prefer option 1
> because the leaf function when running on bare metal is the same as
> the native kernel, so we're not duplicating code.  Thanks,

Okey, I will do this.

Anthony
> 
>       Alex

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