[PATCH 4/4] kvmppc: convert wrteei to wrtee as kvm guest optimization

[Arnd Bergmann]

On Tuesday 19 August 2008, ehrhardt at linux.vnet.ibm.com wrote:
> Dependent on the already existing CONFIG_KVM_GUEST config option this patch
> changes wrteei to wrtee allowing the hypervisor to rewrite those to nontrapping
> instructions. Maybe we should split the kvm guest otpimizations in two parts
> one for the overhead free optimizations and on for the rest that might add
> some complexity for non virtualized execution (like this one).
> 
> Signed-off-by: Christian Ehrhardt <ehrhardt at linux.vnet.ibm.com>

How significant is the performance impact of this change for non-virtualized
systems? If it's very low, maybe you should not bother with the #ifdef, and
if it's noticable, you might be better off using dynamic patching for this.

	Arnd <><