From patchwork Tue Aug 2 11:10:54 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiao Guangrong X-Patchwork-Id: 1029072 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by demeter2.kernel.org (8.14.4/8.14.4) with ESMTP id p72B9GvK015662 for ; Tue, 2 Aug 2011 11:09:16 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753484Ab1HBLI4 (ORCPT ); Tue, 2 Aug 2011 07:08:56 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:50472 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1753239Ab1HBLIy (ORCPT ); Tue, 2 Aug 2011 07:08:54 -0400 Received: from tang.cn.fujitsu.com (tang.cn.fujitsu.com [10.167.250.3]) by song.cn.fujitsu.com (Postfix) with ESMTP id 9155C170124; Tue, 2 Aug 2011 19:08:53 +0800 (CST) Received: from mailserver.fnst.cn.fujitsu.com (tang.cn.fujitsu.com [127.0.0.1]) by tang.cn.fujitsu.com (8.14.3/8.13.1) with ESMTP id p72B8rXU003368; Tue, 2 Aug 2011 19:08:53 +0800 Received: from localhost.localdomain ([10.167.225.99]) by mailserver.fnst.cn.fujitsu.com (Lotus Domino Release 8.5.1FP4) with ESMTP id 2011080219075529-26108 ; Tue, 2 Aug 2011 19:07:55 +0800 Message-ID: <4E37DB3E.2040306@cn.fujitsu.com> Date: Tue, 02 Aug 2011 19:10:54 +0800 From: Xiao Guangrong User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.17) Gecko/20110428 Fedora/3.1.10-1.fc15 Thunderbird/3.1.10 MIME-Version: 1.0 To: Avi Kivity CC: Marcelo Tosatti , LKML , KVM Subject: [PATCH v2 08/12] KVM: MMU: fast prefetch spte on invlpg path References: <4E37DA49.1040000@cn.fujitsu.com> In-Reply-To: <4E37DA49.1040000@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at 2011-08-02 19:07:55, Serialize by Router on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at 2011-08-02 19:07:56, Serialize complete at 2011-08-02 19:07:56 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.6 (demeter2.kernel.org [140.211.167.43]); Tue, 02 Aug 2011 11:09:17 +0000 (UTC) Fast prefetch spte for the unsync shadow page on invlpg path Signed-off-by: Xiao Guangrong --- arch/x86/include/asm/kvm_host.h | 3 +-- arch/x86/kvm/mmu.c | 37 +++++++++++++++---------------------- arch/x86/kvm/paging_tmpl.h | 23 ++++++++++------------- arch/x86/kvm/x86.c | 4 ++-- 4 files changed, 28 insertions(+), 39 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index b256660..2c08458 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -456,7 +456,6 @@ struct kvm_arch { unsigned int n_requested_mmu_pages; unsigned int n_max_mmu_pages; unsigned int indirect_shadow_pages; - atomic_t invlpg_counter; struct hlist_head mmu_page_hash[KVM_NUM_MMU_PAGES]; /* * Hash table of struct kvm_mmu_page. @@ -749,7 +748,7 @@ int fx_init(struct kvm_vcpu *vcpu); void kvm_mmu_flush_tlb(struct kvm_vcpu *vcpu); void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, const u8 *new, int bytes, - bool guest_initiated, bool page_table_written); + bool page_table_written); int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva); void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu); int kvm_mmu_load(struct kvm_vcpu *vcpu); diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 8e97ffa..5517115 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -3526,7 +3526,7 @@ static bool last_updated_pte_accessed(struct kvm_vcpu *vcpu) void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, const u8 *new, int bytes, - bool guest_initiated, bool page_table_written) + bool page_table_written) { gfn_t gfn = gpa >> PAGE_SHIFT; union kvm_mmu_page_role mask = { .word = 0 }; @@ -3535,7 +3535,7 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, LIST_HEAD(invalid_list); u64 entry, gentry, *spte; unsigned pte_size, page_offset, misaligned, quadrant, offset; - int level, npte, invlpg_counter, r, flooded = 0; + int level, npte, r, flooded = 0; bool remote_flush, local_flush, zap_page; /* @@ -3550,19 +3550,16 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, pgprintk("%s: gpa %llx bytes %d\n", __func__, gpa, bytes); - invlpg_counter = atomic_read(&vcpu->kvm->arch.invlpg_counter); - /* * Assume that the pte write on a page table of the same type * as the current vcpu paging mode since we update the sptes only * when they have the same mode. */ - if ((is_pae(vcpu) && bytes == 4) || !new) { + if (is_pae(vcpu) && bytes == 4) { /* Handle a 32-bit guest writing two halves of a 64-bit gpte */ - if (is_pae(vcpu)) { - gpa &= ~(gpa_t)7; - bytes = 8; - } + gpa &= ~(gpa_t)7; + bytes = 8; + r = kvm_read_guest(vcpu->kvm, gpa, &gentry, min(bytes, 8)); if (r) gentry = 0; @@ -3588,22 +3585,18 @@ void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, */ mmu_topup_memory_caches(vcpu); spin_lock(&vcpu->kvm->mmu_lock); - if (atomic_read(&vcpu->kvm->arch.invlpg_counter) != invlpg_counter) - gentry = 0; kvm_mmu_free_some_pages(vcpu); ++vcpu->kvm->stat.mmu_pte_write; trace_kvm_mmu_audit(vcpu, AUDIT_PRE_PTE_WRITE); - if (guest_initiated) { - if (gfn == vcpu->arch.last_pt_write_gfn - && !last_updated_pte_accessed(vcpu)) { - ++vcpu->arch.last_pt_write_count; - if (vcpu->arch.last_pt_write_count >= 3) - flooded = 1; - } else { - vcpu->arch.last_pt_write_gfn = gfn; - vcpu->arch.last_pt_write_count = 1; - vcpu->arch.last_pte_updated = NULL; - } + if (gfn == vcpu->arch.last_pt_write_gfn + && !last_updated_pte_accessed(vcpu)) { + ++vcpu->arch.last_pt_write_count; + if (vcpu->arch.last_pt_write_count >= 3) + flooded = 1; + } else { + vcpu->arch.last_pt_write_gfn = gfn; + vcpu->arch.last_pt_write_count = 1; + vcpu->arch.last_pte_updated = NULL; } mask.cr0_wp = mask.cr4_pae = mask.nxe = 1; diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h index 0f915b5..3466229 100644 --- a/arch/x86/kvm/paging_tmpl.h +++ b/arch/x86/kvm/paging_tmpl.h @@ -666,20 +666,22 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva) { struct kvm_shadow_walk_iterator iterator; struct kvm_mmu_page *sp; - gpa_t pte_gpa = -1; int level; u64 *sptep; vcpu_clear_mmio_info(vcpu, gva); + mmu_topup_memory_caches(vcpu); spin_lock(&vcpu->kvm->mmu_lock); - for_each_shadow_entry(vcpu, gva, iterator) { level = iterator.level; sptep = iterator.sptep; sp = page_header(__pa(sptep)); if (is_last_spte(*sptep, level)) { + pt_element_t gpte; + gpa_t pte_gpa; + if (!sp->unsync) break; @@ -688,23 +690,18 @@ static void FNAME(invlpg)(struct kvm_vcpu *vcpu, gva_t gva) if (mmu_page_zap_pte(vcpu->kvm, sp, sptep)) kvm_flush_remote_tlbs(vcpu->kvm); + + if (kvm_read_guest_atomic(vcpu->kvm, pte_gpa, &gpte, + sizeof(pt_element_t))) + break; + + FNAME(update_pte)(vcpu, sp, sptep, &gpte); } if (!is_shadow_present_pte(*sptep) || !sp->unsync_children) break; } - - atomic_inc(&vcpu->kvm->arch.invlpg_counter); - spin_unlock(&vcpu->kvm->mmu_lock); - - if (pte_gpa == -1) - return; - - if (mmu_topup_memory_caches(vcpu)) - return; - kvm_mmu_pte_write(vcpu, pte_gpa, NULL, sizeof(pt_element_t), - false, true); } static gpa_t FNAME(gva_to_gpa)(struct kvm_vcpu *vcpu, gva_t vaddr, u32 access, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 64f920d..fd83f3c 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4065,7 +4065,7 @@ int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa, ret = kvm_write_guest(vcpu->kvm, gpa, val, bytes); if (ret < 0) return 0; - kvm_mmu_pte_write(vcpu, gpa, val, bytes, true, page_table_written); + kvm_mmu_pte_write(vcpu, gpa, val, bytes, page_table_written); return 1; } @@ -4326,7 +4326,7 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, if (!exchanged) return X86EMUL_CMPXCHG_FAILED; - kvm_mmu_pte_write(vcpu, gpa, new, bytes, true, true); + kvm_mmu_pte_write(vcpu, gpa, new, bytes, true); return X86EMUL_CONTINUE;