From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756695Ab0ITPUL (ORCPT ); Mon, 20 Sep 2010 11:20:11 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55389 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752119Ab0ITPUK (ORCPT ); Mon, 20 Sep 2010 11:20:10 -0400 Message-ID: <4C977B9E.6030208@redhat.com> Date: Mon, 20 Sep 2010 17:19:58 +0200 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.9) Gecko/20100907 Fedora/3.1.3-1.fc13 Lightning/1.0b3pre Thunderbird/3.1.3 MIME-Version: 1.0 To: Xiao Guangrong CC: Marcelo Tosatti , LKML , KVM Subject: Re: [PATCH 2/4] KVM: MMU: support unsync sp out of the protection of 'mmu_lock' References: <4C976D48.6020400@cn.fujitsu.com> <4C976D7C.7090707@cn.fujitsu.com> In-Reply-To: <4C976D7C.7090707@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/20/2010 04:19 PM, Xiao Guangrong wrote: > It allows keep unsync sp alive while it's out of the protection, later we can use > kvm_mmu_free_page() to free it if !sp->active_count Don't understand. Of course unsync pages exist outside mmu_lock...? > > diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c > index 839852d..4b7af3f 100644 > --- a/arch/x86/kvm/mmu.c > +++ b/arch/x86/kvm/mmu.c > @@ -996,7 +996,6 @@ static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp) > { > ASSERT(is_empty_shadow_page(sp->spt)); > hlist_del(&sp->hash_link); > - list_del(&sp->link); > __free_page(virt_to_page(sp->spt)); > if (!sp->role.direct) > __free_page(virt_to_page(sp->gfns)); > @@ -1681,9 +1680,8 @@ static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp, > kvm_mmu_unlink_parents(kvm, sp); > if (!sp->role.invalid&& !sp->role.direct) > unaccount_shadowed(kvm, sp->gfn); > - if (sp->unsync) > - kvm_unlink_unsync_page(kvm, sp); > - if (!sp->active_count) { > + > + if (!sp->active_count || sp->unsync) { > /* Count self */ > ret++; > list_move(&sp->link, invalid_list); How can you drop an active unsync page? I'm missing something here. > @@ -1692,6 +1690,8 @@ static int kvm_mmu_prepare_zap_page(struct kvm *kvm, struct kvm_mmu_page *sp, > kvm_reload_remote_mmus(kvm); > } > > + if (sp->unsync) > + kvm_unlink_unsync_page(kvm, sp); > sp->role.invalid = 1; > kvm_mmu_reset_last_pte_updated(kvm); > return ret; > @@ -1709,8 +1709,12 @@ static void kvm_mmu_commit_zap_page(struct kvm *kvm, > > do { > sp = list_first_entry(invalid_list, struct kvm_mmu_page, link); > - WARN_ON(!sp->role.invalid || sp->active_count); > - kvm_mmu_free_page(kvm, sp); > + WARN_ON(!sp->role.invalid); > + list_del(&sp->link); > + if (sp->active_count) > + WARN_ON(!sp->unsync); > + else > + kvm_mmu_free_page(kvm, sp); > } while (!list_empty(invalid_list)); > > } -- error compiling committee.c: too many arguments to function