From mboxrd@z Thu Jan 1 00:00:00 1970 From: lantianyu1986@gmail.com Subject: [Resend PATCH V5 8/10] KVM/MMU: Move tlb flush in kvm_set_pte_rmapp() to kvm_mmu_notifier_change_pte() Date: Thu, 6 Dec 2018 21:21:11 +0800 Message-ID: <20181206132113.2691-9-Tianyu.Lan@microsoft.com> References: <20181206132113.2691-1-Tianyu.Lan@microsoft.com> Cc: Lan Tianyu , pbonzini@redhat.com, rkrcmar@redhat.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, x86@kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, michael.h.kelley@microsoft.com, kys@microsoft.com, vkuznets@redhat.com, linux@armlinux.org.uk To: unlisted-recipients:; (no To-header on input) Return-path: In-Reply-To: <20181206132113.2691-1-Tianyu.Lan@microsoft.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: kvm.vger.kernel.org From: Lan Tianyu This patch is to move tlb flush in kvm_set_pte_rmapp() to kvm_mmu_notifier_change_pte() in order to avoid redundant tlb flush. Signed-off-by: Lan Tianyu --- arch/x86/kvm/mmu.c | 8 ++------ virt/kvm/kvm_main.c | 5 ++++- 2 files changed, 6 insertions(+), 7 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index dfef49f1e7a6..3b0f60e88f54 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1776,10 +1776,7 @@ static int kvm_set_pte_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head, } } - if (need_flush) - kvm_flush_remote_tlbs(kvm); - - return 0; + return need_flush; } struct slot_rmap_walk_iterator { @@ -1915,8 +1912,7 @@ int kvm_unmap_hva_range(struct kvm *kvm, unsigned long start, unsigned long end) int kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte) { - kvm_handle_hva(kvm, hva, (unsigned long)&pte, kvm_set_pte_rmapp); - return 0; + return kvm_handle_hva(kvm, hva, (unsigned long)&pte, kvm_set_pte_rmapp); } static int kvm_age_rmapp(struct kvm *kvm, struct kvm_rmap_head *rmap_head, diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 2679e476b6c3..dac4b0446aed 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -354,7 +354,10 @@ static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn, idx = srcu_read_lock(&kvm->srcu); spin_lock(&kvm->mmu_lock); kvm->mmu_notifier_seq++; - kvm_set_spte_hva(kvm, address, pte); + + if (kvm_set_spte_hva(kvm, address, pte)) + kvm_flush_remote_tlbs(kvm); + spin_unlock(&kvm->mmu_lock); srcu_read_unlock(&kvm->srcu, idx); } -- 2.14.4