From mboxrd@z Thu Jan 1 00:00:00 1970 From: Xiao Guangrong Subject: Re: [PATCH 7/7] KVM: MMU: cache guest page number to guest frame number Date: Wed, 23 Feb 2011 09:38:31 +0800 Message-ID: <4D646517.8030702@cn.fujitsu.com> References: <4D636EF8.60800@cn.fujitsu.com> <4D6370E8.6080008@cn.fujitsu.com> <4D63C8F9.1020708@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Marcelo Tosatti , LKML , KVM To: Avi Kivity Return-path: In-Reply-To: <4D63C8F9.1020708@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org On 02/22/2011 10:32 PM, Avi Kivity wrote: > On 02/22/2011 10:16 AM, Xiao Guangrong wrote: >> Cache guest page number to guest frame number to avoid walk guest page table >> frequently, the 'vtlb' idea is from Xen. >> >> Note: >> we can't use vtlb in ept guests since the guest tlb invalid operation is not >> intercept(reload CR3, invlpg), also can't used in L2 nnpt guest for the same >> reason, but we can used it to cache L1's npt page table. >> > > I'm not so hot about introducing a new mechanism strictly for older hosts... EPT exists in three generations of Intel processors now (Sandy Bridge, Westmere, and Nehalem), and NPT is significantly older. > Um...so, do we should stop the new features for softmmu, only bug fix is welcome? :-)