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

2008-08-22 Thread Scott Wood
On Fri, Aug 22, 2008 at 09:56:16AM -0400, Jimi Xenidis wrote: Sorry, I have not really been following this, I assume you are replacing SPR accesses with load/stores that do not trap. I believe thats fine for reading any SPR, but not true for modifying some SPRs, particularly MSR. IMHO you

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

2008-08-21 Thread Kumar Gala
On Aug 19, 2008, at 5:36 AM, [EMAIL PROTECTED] wrote: From: Christian Ehrhardt [EMAIL PROTECTED] 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

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

2008-08-21 Thread Christian Ehrhardt
Kumar Gala wrote: On Aug 19, 2008, at 5:36 AM, [EMAIL PROTECTED] wrote: From: Christian Ehrhardt [EMAIL PROTECTED] 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

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

2008-08-20 Thread Hollis Blanchard
On Wed, 2008-08-20 at 14:53 +0200, Christian Ehrhardt wrote: Arnd Bergmann wrote: On Tuesday 19 August 2008, [EMAIL PROTECTED] wrote: Dependent on the already existing CONFIG_KVM_GUEST config option this patch changes wrteei to wrtee allowing the hypervisor to rewrite those to

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

2008-08-20 Thread Hollis Blanchard
On Wed, 2008-08-20 at 14:52 -0400, Josh Boyer wrote: On Wed, 2008-08-20 at 13:30 -0500, Hollis Blanchard wrote: On Wed, 2008-08-20 at 14:53 +0200, Christian Ehrhardt wrote: Arnd Bergmann wrote: On Tuesday 19 August 2008, [EMAIL PROTECTED] wrote: Dependent on the already

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

2008-08-20 Thread Josh Boyer
On Wed, 20 Aug 2008 14:06:51 -0500 Hollis Blanchard [EMAIL PROTECTED] wrote: To be honest I unfortunately don't know how big the impact for non-virtualized systems is. I would like to test it, but without hardware performance counters on the core I have I'm not sure (yet) how

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

2008-08-19 Thread Arnd Bergmann
On Tuesday 19 August 2008, [EMAIL PROTECTED] 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