Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753678Ab0KLG7w (ORCPT ); Fri, 12 Nov 2010 01:59:52 -0500 Received: from cn.fujitsu.com ([222.73.24.84]:52951 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1751771Ab0KLG7t (ORCPT ); Fri, 12 Nov 2010 01:59:49 -0500 Message-ID: <4CDCE3C2.9030107@cn.fujitsu.com> Date: Fri, 12 Nov 2010 14:50:42 +0800 From: Xiao Guangrong User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.11) Gecko/20100713 Thunderbird/3.0.6 MIME-Version: 1.0 To: Avi Kivity CC: Marcelo Tosatti , Gleb Natapov , LKML , KVM Subject: [PATCH v2 5/5] KVM: MMU: retry #PF for softmmu References: <4CDCE2B0.7000601@cn.fujitsu.com> In-Reply-To: <4CDCE2B0.7000601@cn.fujitsu.com> X-MIMETrack: Itemize by SMTP Server on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at 2010-11-12 14:46:49, Serialize by Router on mailserver/fnst(Release 8.5.1FP4|July 25, 2010) at 2010-11-12 15:00:14, Serialize complete at 2010-11-12 15:00:14 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5978 Lines: 191 Retry #PF for softmmu only when the current vcpu has the same root shadow page as the time when #PF occurs. it means they have same paging environment Signed-off-by: Xiao Guangrong --- arch/x86/include/asm/kvm_host.h | 6 ++++++ arch/x86/kvm/mmu.c | 35 ++++++++++++++++++++++++++++++++++- arch/x86/kvm/x86.c | 15 ++++++++++++++- virt/kvm/async_pf.c | 1 + 4 files changed, 55 insertions(+), 2 deletions(-) diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h index b04c0fa..2cefe00 100644 --- a/arch/x86/include/asm/kvm_host.h +++ b/arch/x86/include/asm/kvm_host.h @@ -192,6 +192,8 @@ struct kvm_mmu_page { struct list_head link; struct hlist_node hash_link; + struct kref apfs_counter; + /* * The following two entries are used to key the shadow page in the * hash table. @@ -600,6 +602,7 @@ struct kvm_x86_ops { struct kvm_arch_async_pf { u32 token; gfn_t gfn; + struct kvm_mmu_page *root_sp; bool direct_map; }; @@ -698,6 +701,8 @@ void kvm_inject_nmi(struct kvm_vcpu *vcpu); int fx_init(struct kvm_vcpu *vcpu); +struct kvm_mmu_page *get_vcpu_root_sp(struct kvm_vcpu *vcpu, gva_t gva); +void kvm_mmu_release_apf_sp(struct kvm_mmu_page *sp); 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, @@ -816,6 +821,7 @@ void kvm_set_shared_msr(unsigned index, u64 val, u64 mask); bool kvm_is_linear_rip(struct kvm_vcpu *vcpu, unsigned long linear_rip); +void kvm_arch_clear_async_pf(struct kvm_async_pf *work); void kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu, struct kvm_async_pf *work); void kvm_arch_async_page_present(struct kvm_vcpu *vcpu, diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index bdb9fa9..4b6d54c 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -993,6 +993,19 @@ static inline void kvm_mod_used_mmu_pages(struct kvm *kvm, int nr) percpu_counter_add(&kvm_total_used_mmu_pages, nr); } +static void free_shadow_page(struct kref *kref) +{ + struct kvm_mmu_page *sp; + + sp = container_of(kref, struct kvm_mmu_page, apfs_counter); + kmem_cache_free(mmu_page_header_cache, sp); +} + +void kvm_mmu_release_apf_sp(struct kvm_mmu_page *sp) +{ + kref_put(&sp->apfs_counter, free_shadow_page); +} + static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp) { ASSERT(is_empty_shadow_page(sp->spt)); @@ -1001,7 +1014,7 @@ static void kvm_mmu_free_page(struct kvm *kvm, struct kvm_mmu_page *sp) __free_page(virt_to_page(sp->spt)); if (!sp->role.direct) __free_page(virt_to_page(sp->gfns)); - kmem_cache_free(mmu_page_header_cache, sp); + kvm_mmu_release_apf_sp(sp); kvm_mod_used_mmu_pages(kvm, -1); } @@ -1026,6 +1039,8 @@ static struct kvm_mmu_page *kvm_mmu_alloc_page(struct kvm_vcpu *vcpu, sp->multimapped = 0; sp->parent_pte = parent_pte; kvm_mod_used_mmu_pages(vcpu->kvm, +1); + kref_init(&sp->apfs_counter); + return sp; } @@ -2603,13 +2618,31 @@ static int nonpaging_page_fault(struct kvm_vcpu *vcpu, gva_t gva, error_code & PFERR_WRITE_MASK, gfn, no_apf); } +struct kvm_mmu_page *get_vcpu_root_sp(struct kvm_vcpu *vcpu, gva_t gva) +{ + struct kvm_shadow_walk_iterator iterator; + bool ret; + + shadow_walk_init(&iterator, vcpu, gva); + ret = shadow_walk_okay(&iterator); + WARN_ON(!ret); + + return page_header(__pa(iterator.sptep)); +} + static int kvm_arch_setup_async_pf(struct kvm_vcpu *vcpu, gva_t gva, gfn_t gfn) { struct kvm_arch_async_pf arch; + arch.token = (vcpu->arch.apf.id++ << 12) | vcpu->vcpu_id; arch.gfn = gfn; arch.direct_map = vcpu->arch.mmu.direct_map; + if (!arch.direct_map) { + arch.root_sp = get_vcpu_root_sp(vcpu, gva); + kref_get(&arch.root_sp->apfs_counter); + } + return kvm_setup_async_pf(vcpu, gva, gfn, &arch); } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 003a0ca..1ecc1a9 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6169,7 +6169,7 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work) { int r; - if (!vcpu->arch.mmu.direct_map || !work->arch.direct_map || + if (vcpu->arch.mmu.direct_map != work->arch.direct_map || is_error_page(work->page)) return; @@ -6177,6 +6177,10 @@ void kvm_arch_async_page_ready(struct kvm_vcpu *vcpu, struct kvm_async_pf *work) if (unlikely(r)) return; + if (!vcpu->arch.mmu.direct_map && + get_vcpu_root_sp(vcpu, work->gva) != work->arch.root_sp) + return; + vcpu->arch.mmu.page_fault(vcpu, work->gva, 0, true); } @@ -6248,6 +6252,12 @@ static int apf_put_user(struct kvm_vcpu *vcpu, u32 val) sizeof(val)); } +void kvm_arch_clear_async_pf(struct kvm_async_pf *work) +{ + if (!work->arch.direct_map) + kvm_mmu_release_apf_sp(work->arch.root_sp); +} + void kvm_arch_async_page_not_present(struct kvm_vcpu *vcpu, struct kvm_async_pf *work) { @@ -6269,6 +6279,9 @@ void kvm_arch_async_page_present(struct kvm_vcpu *vcpu, struct kvm_async_pf *work) { trace_kvm_async_pf_ready(work->arch.token, work->gva); + + kvm_arch_clear_async_pf(work); + if (is_error_page(work->page)) work->arch.token = ~0; /* broadcast wakeup */ else diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c index 74268b4..c3d4788 100644 --- a/virt/kvm/async_pf.c +++ b/virt/kvm/async_pf.c @@ -101,6 +101,7 @@ void kvm_clear_async_pf_completion_queue(struct kvm_vcpu *vcpu) typeof(*work), queue); cancel_work_sync(&work->work); list_del(&work->queue); + kvm_arch_clear_async_pf(work); if (!work->done) /* work was canceled */ kmem_cache_free(async_pf_cache, work); } -- 1.7.0.4 -- 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/