From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757293AbcBWEtD (ORCPT ); Mon, 22 Feb 2016 23:49:03 -0500 Received: from mga14.intel.com ([192.55.52.115]:26590 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756675AbcBWEtA (ORCPT ); Mon, 22 Feb 2016 23:49:00 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,488,1449561600"; d="scan'208";a="751365624" Subject: Re: [PATCH v3 11/11] KVM: MMU: apply page track notifier To: Paolo Bonzini References: <1455449503-20993-1-git-send-email-guangrong.xiao@linux.intel.com> <1455449503-20993-12-git-send-email-guangrong.xiao@linux.intel.com> <56C702F9.3070309@redhat.com> Cc: gleb@kernel.org, mtosatti@redhat.com, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, kai.huang@linux.intel.com, jike.song@intel.com From: Xiao Guangrong Message-ID: <56CBE2C2.7020005@linux.intel.com> Date: Tue, 23 Feb 2016 12:40:34 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <56C702F9.3070309@redhat.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 02/19/2016 07:56 PM, Paolo Bonzini wrote: > > > On 14/02/2016 12:31, Xiao Guangrong wrote: >> Register the notifier to receive write track event so that we can update >> our shadow page table >> >> It makes kvm_mmu_pte_write() be the callback of the notifier, no function >> is changed >> >> Signed-off-by: Xiao Guangrong >> --- >> arch/x86/include/asm/kvm_host.h | 5 +++-- >> arch/x86/kvm/mmu.c | 19 +++++++++++++++++-- >> arch/x86/kvm/x86.c | 4 ++-- >> 3 files changed, 22 insertions(+), 6 deletions(-) >> >> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h >> index 254d103..5246f07 100644 >> --- a/arch/x86/include/asm/kvm_host.h >> +++ b/arch/x86/include/asm/kvm_host.h >> @@ -696,6 +696,7 @@ struct kvm_arch { >> */ >> struct list_head active_mmu_pages; >> struct list_head zapped_obsolete_pages; >> + struct kvm_page_track_notifier_node mmu_sp_tracker; >> struct kvm_page_track_notifier_head track_notifier_head; >> >> struct list_head assigned_dev_head; >> @@ -994,6 +995,8 @@ void kvm_mmu_module_exit(void); >> void kvm_mmu_destroy(struct kvm_vcpu *vcpu); >> int kvm_mmu_create(struct kvm_vcpu *vcpu); >> void kvm_mmu_setup(struct kvm_vcpu *vcpu); >> +void kvm_mmu_init_vm(struct kvm *kvm); >> +void kvm_mmu_uninit_vm(struct kvm *kvm); >> void kvm_mmu_set_mask_ptes(u64 user_mask, u64 accessed_mask, >> u64 dirty_mask, u64 nx_mask, u64 x_mask); >> >> @@ -1133,8 +1136,6 @@ void kvm_pic_clear_all(struct kvm_pic *pic, int irq_source_id); >> >> void kvm_inject_nmi(struct kvm_vcpu *vcpu); >> >> -void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, >> - const u8 *new, int bytes); >> int kvm_mmu_unprotect_page(struct kvm *kvm, gfn_t gfn); >> int kvm_mmu_unprotect_page_virt(struct kvm_vcpu *vcpu, gva_t gva); >> void __kvm_mmu_free_some_pages(struct kvm_vcpu *vcpu); >> diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c >> index f924e6c..57cf30b 100644 >> --- a/arch/x86/kvm/mmu.c >> +++ b/arch/x86/kvm/mmu.c >> @@ -4316,8 +4316,8 @@ static u64 *get_written_sptes(struct kvm_mmu_page *sp, gpa_t gpa, int *nspte) >> return spte; >> } >> >> -void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, >> - const u8 *new, int bytes) >> +static void kvm_mmu_pte_write(struct kvm_vcpu *vcpu, gpa_t gpa, >> + const u8 *new, int bytes) >> { >> gfn_t gfn = gpa >> PAGE_SHIFT; >> struct kvm_mmu_page *sp; >> @@ -4531,6 +4531,21 @@ void kvm_mmu_setup(struct kvm_vcpu *vcpu) >> init_kvm_mmu(vcpu); >> } >> >> +void kvm_mmu_init_vm(struct kvm *kvm) >> +{ >> + struct kvm_page_track_notifier_node *node = &kvm->arch.mmu_sp_tracker; >> + >> + node->track_write = kvm_mmu_pte_write; >> + kvm_page_track_register_notifier(kvm, node); >> +} >> + >> +void kvm_mmu_uninit_vm(struct kvm *kvm) >> +{ >> + struct kvm_page_track_notifier_node *node = &kvm->arch.mmu_sp_tracker; >> + >> + kvm_page_track_unregister_notifier(kvm, node); >> +} >> + >> /* The return value indicates if tlb flush on all vcpus is needed. */ >> typedef bool (*slot_level_handler) (struct kvm *kvm, struct kvm_rmap_head *rmap_head); >> >> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c >> index 98019b6..319d572 100644 >> --- a/arch/x86/kvm/x86.c >> +++ b/arch/x86/kvm/x86.c >> @@ -4369,7 +4369,6 @@ int emulator_write_phys(struct kvm_vcpu *vcpu, gpa_t gpa, >> ret = kvm_vcpu_write_guest(vcpu, gpa, val, bytes); >> if (ret < 0) >> return 0; >> - kvm_mmu_pte_write(vcpu, gpa, val, bytes); >> kvm_page_track_write(vcpu, gpa, val, bytes); >> return 1; >> } >> @@ -4628,7 +4627,6 @@ static int emulator_cmpxchg_emulated(struct x86_emulate_ctxt *ctxt, >> return X86EMUL_CMPXCHG_FAILED; >> >> kvm_vcpu_mark_page_dirty(vcpu, gpa >> PAGE_SHIFT); >> - kvm_mmu_pte_write(vcpu, gpa, new, bytes); >> kvm_page_track_write(vcpu, gpa, new, bytes); >> >> return X86EMUL_CONTINUE; >> @@ -7751,6 +7749,7 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) >> INIT_DELAYED_WORK(&kvm->arch.kvmclock_sync_work, kvmclock_sync_fn); >> >> kvm_page_track_init(kvm); >> + kvm_mmu_init_vm(kvm); >> >> return 0; >> } >> @@ -7878,6 +7877,7 @@ void kvm_arch_destroy_vm(struct kvm *kvm) >> kfree(kvm->arch.vioapic); >> kvm_free_vcpus(kvm); >> kfree(rcu_dereference_check(kvm->arch.apic_map, 1)); >> + kvm_mmu_uninit_vm(kvm); > > This function is not necessary, since the VM is disappearing anyway and > the page tracker is not going to be called. I think it is still necessary, as we are using srcu to protect the notifier, so we should wait all the callers of notifier callbacks gone, i.e, synchronize_srcu() is needed anyway.