Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752866Ab0DYHEW (ORCPT ); Sun, 25 Apr 2010 03:04:22 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:51043 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751890Ab0DYHES (ORCPT ); Sun, 25 Apr 2010 03:04:18 -0400 Message-ID: <4BD3E8B3.5030704@cn.fujitsu.com> Date: Sun, 25 Apr 2010 15:01:07 +0800 From: Xiao Guangrong User-Agent: Thunderbird 2.0.0.24 (Windows/20100228) MIME-Version: 1.0 To: Avi Kivity CC: Marcelo Tosatti , KVM list , LKML Subject: [PATCH v2 7/10] KVM MMU: allow more page become unsync at gfn mapping time References: <4BD3E306.4020202@cn.fujitsu.com> In-Reply-To: <4BD3E306.4020202@cn.fujitsu.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3940 Lines: 137 In current code, shadow page can become asynchronous only if one shadow page for a gfn, this rule is too strict, in fact, we can let all last mapping page(i.e, it's the pte page) become unsync, and sync them at invlpg or flush tlb time. This patch allow more page become asynchronous at gfn mapping time Signed-off-by: Xiao Guangrong --- arch/x86/kvm/mmu.c | 81 +++++++++++++++++++++++---------------------------- 1 files changed, 37 insertions(+), 44 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index b946a5f..5198fc9 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1166,26 +1166,6 @@ static int mmu_unsync_walk(struct kvm_mmu_page *sp, return __mmu_unsync_walk(sp, pvec); } -static struct kvm_mmu_page *kvm_mmu_lookup_page(struct kvm *kvm, gfn_t gfn) -{ - unsigned index; - struct hlist_head *bucket; - struct kvm_mmu_page *sp; - struct hlist_node *node; - - pgprintk("%s: looking for gfn %lx\n", __func__, gfn); - index = kvm_page_table_hashfn(gfn); - bucket = &kvm->arch.mmu_page_hash[index]; - hlist_for_each_entry(sp, node, bucket, hash_link) - if (sp->gfn == gfn && !sp->role.direct - && !sp->role.invalid) { - pgprintk("%s: found role %x\n", - __func__, sp->role.word); - return sp; - } - return NULL; -} - static void kvm_unlink_unsync_page(struct kvm *kvm, struct kvm_mmu_page *sp) { WARN_ON(!sp->unsync); @@ -1748,47 +1728,60 @@ u8 kvm_get_guest_memory_type(struct kvm_vcpu *vcpu, gfn_t gfn) } EXPORT_SYMBOL_GPL(kvm_get_guest_memory_type); -static int kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) +static void __kvm_unsync_page(struct kvm_vcpu *vcpu, struct kvm_mmu_page *sp) +{ + trace_kvm_mmu_unsync_page(sp); + ++vcpu->kvm->stat.mmu_unsync; + sp->unsync = 1; + + kvm_mmu_mark_parents_unsync(sp); + mmu_convert_notrap(sp); +} + +static void kvm_unsync_pages(struct kvm_vcpu *vcpu, gfn_t gfn) { - unsigned index; struct hlist_head *bucket; struct kvm_mmu_page *s; struct hlist_node *node, *n; + unsigned index; - index = kvm_page_table_hashfn(sp->gfn); + index = kvm_page_table_hashfn(gfn); bucket = &vcpu->kvm->arch.mmu_page_hash[index]; - /* don't unsync if pagetable is shadowed with multiple roles */ + hlist_for_each_entry_safe(s, node, n, bucket, hash_link) { - if (s->gfn != sp->gfn || s->role.direct) + if (s->gfn != gfn || s->role.direct || s->unsync) continue; - if (s->role.word != sp->role.word) - return 1; + WARN_ON(s->role.level != PT_PAGE_TABLE_LEVEL); + __kvm_unsync_page(vcpu, s); } - trace_kvm_mmu_unsync_page(sp); - ++vcpu->kvm->stat.mmu_unsync; - sp->unsync = 1; - - kvm_mmu_mark_parents_unsync(sp); - - mmu_convert_notrap(sp); - return 0; } static int mmu_need_write_protect(struct kvm_vcpu *vcpu, gfn_t gfn, bool can_unsync) { - struct kvm_mmu_page *shadow; + unsigned index; + struct hlist_head *bucket; + struct kvm_mmu_page *s; + struct hlist_node *node, *n; + bool need_unsync = false; + + index = kvm_page_table_hashfn(gfn); + bucket = &vcpu->kvm->arch.mmu_page_hash[index]; + hlist_for_each_entry_safe(s, node, n, bucket, hash_link) { + if (s->gfn != gfn || s->role.direct) + continue; - shadow = kvm_mmu_lookup_page(vcpu->kvm, gfn); - if (shadow) { - if (shadow->role.level != PT_PAGE_TABLE_LEVEL) + if (s->role.level != PT_PAGE_TABLE_LEVEL) return 1; - if (shadow->unsync) - return 0; - if (can_unsync && oos_shadow) - return kvm_unsync_page(vcpu, shadow); - return 1; + + if (!need_unsync && !s->unsync) { + if (!can_unsync || !oos_shadow) + return 1; + need_unsync = true; + } } + if (need_unsync) + kvm_unsync_pages(vcpu, gfn); return 0; } -- 1.6.1.2 -- 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/