Re: [PATCH 3/6] KVM MMU: optimize/cleanup for marking parent unsync

On Wed, Apr 14, 2010 at 11:23:38AM +0800, Xiao Guangrong wrote: Marcelo Tosatti wrote: I'd prefer to not touch it. This patch avoids walk all parents and i think this overload is really unnecessary. It has other tricks in this codepath but i not noticed? :-) My point is that

Re: [PATCH 3/6] KVM MMU: optimize/cleanup for marking parent unsync

On Tue, Apr 13, 2010 at 09:53:07AM +0800, Xiao Guangrong wrote: Marcelo Tosatti wrote: Xiao, Did you actually see this codepath as being performance sensitive? Actually, i not run benchmarks to contrast the performance before this patch and after this patch. I'd prefer to

Re: [PATCH 3/6] KVM MMU: optimize/cleanup for marking parent unsync

Marcelo Tosatti wrote: I'd prefer to not touch it. This patch avoids walk all parents and i think this overload is really unnecessary. It has other tricks in this codepath but i not noticed? :-) My point is that there is no point in optimizing something unless its performance

[PATCH 3/6] KVM MMU: optimize/cleanup for marking parent unsync

- 'vcpu' is not used while mark parent unsync, so remove it - if it has alread marked unsync, no need to walk it's parent Signed-off-by: Xiao Guangrong xiaoguangr...@cn.fujitsu.com --- arch/x86/kvm/mmu.c | 69 +-- 1 files changed, 23

Re: [PATCH 3/6] KVM MMU: optimize/cleanup for marking parent unsync

On 04/12/2010 11:02 AM, Xiao Guangrong wrote: - 'vcpu' is not used while mark parent unsync, so remove it - if it has alread marked unsync, no need to walk it's parent Please separate these two changes. The optimization looks good. Perhaps it can be done even nicer using mutually

Re: [PATCH 3/6] KVM MMU: optimize/cleanup for marking parent unsync

Avi Kivity wrote: On 04/12/2010 11:02 AM, Xiao Guangrong wrote: - 'vcpu' is not used while mark parent unsync, so remove it - if it has alread marked unsync, no need to walk it's parent Please separate these two changes. The optimization looks good. Perhaps it can be done even

Re: [PATCH 3/6] KVM MMU: optimize/cleanup for marking parent unsync

On Mon, Apr 12, 2010 at 04:02:24PM +0800, Xiao Guangrong wrote: - 'vcpu' is not used while mark parent unsync, so remove it - if it has alread marked unsync, no need to walk it's parent Signed-off-by: Xiao Guangrong xiaoguangr...@cn.fujitsu.com Xiao, Did you actually see this codepath as

Re: [PATCH 3/6] KVM MMU: optimize/cleanup for marking parent unsync

Marcelo Tosatti wrote: Xiao, Did you actually see this codepath as being performance sensitive? Actually, i not run benchmarks to contrast the performance before this patch and after this patch. I'd prefer to not touch it. This patch avoids walk all parents and i think this overload