Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757303Ab3FSRkc (ORCPT ); Wed, 19 Jun 2013 13:40:32 -0400 Received: from mail-wi0-f182.google.com ([209.85.212.182]:36218 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756805Ab3FSRka (ORCPT ); Wed, 19 Jun 2013 13:40:30 -0400 Message-ID: <51C1ED05.9040604@redhat.com> Date: Wed, 19 Jun 2013 19:40:21 +0200 From: Paolo Bonzini User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130514 Thunderbird/17.0.6 MIME-Version: 1.0 To: Xiao Guangrong CC: gleb@redhat.com, avi.kivity@gmail.com, mtosatti@redhat.com, linux-kernel@vger.kernel.org, kvm@vger.kernel.org Subject: Re: [PATCH v3 0/6] KVM: MMU: fast invalidate all mmio sptes References: <1370595088-3315-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com> In-Reply-To: <1370595088-3315-1-git-send-email-xiaoguangrong@linux.vnet.ibm.com> X-Enigmail-Version: 1.5.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2661 Lines: 63 Il 07/06/2013 10:51, Xiao Guangrong ha scritto: > Changelog: > V3: > All of these changes are from Gleb's review: > 1) rename RET_MMIO_PF_EMU to RET_MMIO_PF_EMULATE. > 2) smartly adjust kvm generation number in kvm_current_mmio_generatio() > to avoid kvm_memslots->generation overflow. > > V2: > - rename kvm_mmu_invalid_mmio_spte to kvm_mmu_invalid_mmio_sptes > - use kvm->memslots->generation as kvm global generation-number > - fix comment and codestyle > - init kvm generation close to mmio wrap-around value > - keep kvm_mmu_zap_mmio_sptes > > The current way is holding hot mmu-lock and walking all shadow pages, this > is not scale. This patchset tries to introduce a very simple and scale way > to fast invalidate all mmio sptes - it need not walk any shadow pages and hold > any locks. > > The idea is simple: > KVM maintains a global mmio valid generation-number which is stored in > kvm->memslots.generation and every mmio spte stores the current global > generation-number into his available bits when it is created > > When KVM need zap all mmio sptes, it just simply increase the global > generation-number. When guests do mmio access, KVM intercepts a MMIO #PF > then it walks the shadow page table and get the mmio spte. If the > generation-number on the spte does not equal the global generation-number, > it will go to the normal #PF handler to update the mmio spte > > Since 19 bits are used to store generation-number on mmio spte, we zap all > mmio sptes when the number is round > > Xiao Guangrong (6): > KVM: MMU: retain more available bits on mmio spte > KVM: MMU: store generation-number into mmio spte > KVM: MMU: make return value of mmio page fault handler more readable > KVM: MMU: fast invalidate all mmio sptes > KVM: MMU: add tracepoint for check_mmio_spte > KVM: MMU: init kvm generation close to mmio wrap-around value > > arch/x86/include/asm/kvm_host.h | 2 +- > arch/x86/kvm/mmu.c | 131 ++++++++++++++++++++++++++++++++-------- > arch/x86/kvm/mmu.h | 17 ++++++ > arch/x86/kvm/mmutrace.h | 34 +++++++++-- > arch/x86/kvm/paging_tmpl.h | 10 ++- > arch/x86/kvm/vmx.c | 12 ++-- > arch/x86/kvm/x86.c | 11 +++- > 7 files changed, 177 insertions(+), 40 deletions(-) > Applied all to queue for now. Will graduate to next after doing some more tests. Thanks! Paolo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/