From patchwork Sun Aug 5 12:58:32 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gleb Natapov X-Patchwork-Id: 1274851 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 78F07DF27F for ; Sun, 5 Aug 2012 12:59:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754512Ab2HEM7F (ORCPT ); Sun, 5 Aug 2012 08:59:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45684 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754476Ab2HEM65 (ORCPT ); Sun, 5 Aug 2012 08:58:57 -0400 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q75CwvdX016076 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Sun, 5 Aug 2012 08:58:57 -0400 Received: from dhcp-1-237.tlv.redhat.com (dhcp-4-26.tlv.redhat.com [10.35.4.26]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id q75Cwucr021733; Sun, 5 Aug 2012 08:58:56 -0400 Received: by dhcp-1-237.tlv.redhat.com (Postfix, from userid 13519) id 0D91818D480; Sun, 5 Aug 2012 15:58:56 +0300 (IDT) From: Gleb Natapov To: kvm@vger.kernel.org Cc: avi@redhat.com, mtosatti@redhat.com Subject: [PATCH 7/8] KVM: use jump label to optimize checking for in kernel local apic presence. Date: Sun, 5 Aug 2012 15:58:32 +0300 Message-Id: <1344171513-4659-8-git-send-email-gleb@redhat.com> In-Reply-To: <1344171513-4659-1-git-send-email-gleb@redhat.com> References: <1344171513-4659-1-git-send-email-gleb@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Usually all vcpus have local apic pointer initialized, so the check may be completely skipped. Signed-off-by: Gleb Natapov --- arch/x86/kvm/lapic.c | 62 +++++++++++++++++++++++++++----------------------- arch/x86/kvm/x86.c | 7 +++++- arch/x86/kvm/x86.h | 1 + 3 files changed, 41 insertions(+), 29 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 952774c..c97284b 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -152,6 +152,13 @@ static inline int apic_enabled(struct kvm_lapic *apic) return apic_sw_enabled(apic) && apic_hw_enabled(apic); } +static inline bool vcpu_has_lapic(struct kvm_vcpu *vcpu) +{ + if (static_key_false(&kvm_no_apic_vcpu)) + return vcpu->arch.apic; + return true; +} + #define LVT_MASK \ (APIC_LVT_MASKED | APIC_SEND_PENDING | APIC_VECTOR_MASK) @@ -204,7 +211,7 @@ void kvm_apic_set_version(struct kvm_vcpu *vcpu) struct kvm_cpuid_entry2 *feat; u32 v = APIC_VERSION; - if (!irqchip_in_kernel(vcpu->kvm)) + if (!vcpu_has_lapic(vcpu)) return; feat = kvm_find_cpuid_entry(apic->vcpu, 0x1, 0); @@ -305,7 +312,6 @@ static inline void apic_clear_isr(int vec, struct kvm_lapic *apic) int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu) { - struct kvm_lapic *apic = vcpu->arch.apic; int highest_irr; /* This may race with setting of irr in __apic_accept_irq() and @@ -313,9 +319,9 @@ int kvm_lapic_find_highest_irr(struct kvm_vcpu *vcpu) * will cause vmexit immediately and the value will be recalculated * on the next vmentry. */ - if (!apic) + if (!vcpu_has_lapic(vcpu)) return 0; - highest_irr = apic_find_highest_irr(apic); + highest_irr = apic_find_highest_irr(vcpu->arch.apic); return highest_irr; } @@ -1061,9 +1067,7 @@ static int apic_mmio_write(struct kvm_io_device *this, void kvm_lapic_set_eoi(struct kvm_vcpu *vcpu) { - struct kvm_lapic *apic = vcpu->arch.apic; - - if (apic) + if (vcpu_has_lapic(vcpu)) apic_reg_write(vcpu->arch.apic, APIC_EOI, 0); } EXPORT_SYMBOL_GPL(kvm_lapic_set_eoi); @@ -1098,10 +1102,9 @@ void kvm_free_lapic(struct kvm_vcpu *vcpu) u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu) { struct kvm_lapic *apic = vcpu->arch.apic; - if (!apic) - return 0; - if (apic_lvtt_oneshot(apic) || apic_lvtt_period(apic)) + if (!vcpu_has_lapic(vcpu) || apic_lvtt_oneshot(apic) || + apic_lvtt_period(apic)) return 0; return apic->lapic_timer.tscdeadline; @@ -1110,10 +1113,9 @@ u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu) void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data) { struct kvm_lapic *apic = vcpu->arch.apic; - if (!apic) - return; - if (apic_lvtt_oneshot(apic) || apic_lvtt_period(apic)) + if (!vcpu_has_lapic(vcpu) || apic_lvtt_oneshot(apic) || + apic_lvtt_period(apic)) return; hrtimer_cancel(&apic->lapic_timer.timer); @@ -1125,20 +1127,21 @@ void kvm_lapic_set_tpr(struct kvm_vcpu *vcpu, unsigned long cr8) { struct kvm_lapic *apic = vcpu->arch.apic; - if (!apic) + if (!vcpu_has_lapic(vcpu)) return; + apic_set_tpr(apic, ((cr8 & 0x0f) << 4) | (apic_get_reg(apic, APIC_TASKPRI) & 4)); } u64 kvm_lapic_get_cr8(struct kvm_vcpu *vcpu) { - struct kvm_lapic *apic = vcpu->arch.apic; u64 tpr; - if (!apic) + if (!vcpu_has_lapic(vcpu)) return 0; - tpr = (u64) apic_get_reg(apic, APIC_TASKPRI); + + tpr = (u64) apic_get_reg(vcpu->arch.apic, APIC_TASKPRI); return (tpr & 0xf0) >> 4; } @@ -1237,7 +1240,7 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu) bool kvm_apic_present(struct kvm_vcpu *vcpu) { - return vcpu->arch.apic && apic_hw_enabled(vcpu->arch.apic); + return vcpu_has_lapic(vcpu) && apic_hw_enabled(vcpu->arch.apic); } int kvm_lapic_enabled(struct kvm_vcpu *vcpu) @@ -1258,10 +1261,11 @@ static bool lapic_is_periodic(struct kvm_lapic *apic) int apic_has_pending_timer(struct kvm_vcpu *vcpu) { - struct kvm_lapic *lapic = vcpu->arch.apic; + struct kvm_lapic *apic = vcpu->arch.apic; - if (lapic && apic_enabled(lapic) && apic_lvt_enabled(lapic, APIC_LVTT)) - return atomic_read(&lapic->lapic_timer.pending); + if (vcpu_has_lapic(vcpu) && apic_enabled(apic) && + apic_lvt_enabled(apic, APIC_LVTT)) + return atomic_read(&apic->lapic_timer.pending); return 0; } @@ -1371,7 +1375,7 @@ int kvm_apic_has_interrupt(struct kvm_vcpu *vcpu) struct kvm_lapic *apic = vcpu->arch.apic; int highest_irr; - if (!apic || !apic_enabled(apic)) + if (!vcpu_has_lapic(vcpu) || !apic_enabled(apic)) return -1; apic_update_ppr(apic); @@ -1399,7 +1403,10 @@ void kvm_inject_apic_timer_irqs(struct kvm_vcpu *vcpu) { struct kvm_lapic *apic = vcpu->arch.apic; - if (apic && atomic_read(&apic->lapic_timer.pending) > 0) { + if (!vcpu_has_lapic(vcpu)) + return; + + if (atomic_read(&apic->lapic_timer.pending) > 0) { if (kvm_apic_local_deliver(apic, APIC_LVTT)) atomic_dec(&apic->lapic_timer.pending); } @@ -1439,13 +1446,12 @@ void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu) void __kvm_migrate_apic_timer(struct kvm_vcpu *vcpu) { - struct kvm_lapic *apic = vcpu->arch.apic; struct hrtimer *timer; - if (!apic) + if (!vcpu_has_lapic(vcpu)) return; - timer = &apic->lapic_timer.timer; + timer = &vcpu->arch.apic->lapic_timer.timer; if (hrtimer_cancel(timer)) hrtimer_start_expires(timer, HRTIMER_MODE_ABS); } @@ -1602,7 +1608,7 @@ int kvm_hv_vapic_msr_write(struct kvm_vcpu *vcpu, u32 reg, u64 data) { struct kvm_lapic *apic = vcpu->arch.apic; - if (!irqchip_in_kernel(vcpu->kvm)) + if (!vcpu_has_lapic(vcpu)) return 1; /* if this is ICR write vector before command */ @@ -1616,7 +1622,7 @@ int kvm_hv_vapic_msr_read(struct kvm_vcpu *vcpu, u32 reg, u64 *data) struct kvm_lapic *apic = vcpu->arch.apic; u32 low, high = 0; - if (!irqchip_in_kernel(vcpu->kvm)) + if (!vcpu_has_lapic(vcpu)) return 1; if (apic_reg_read(apic, reg, 4, &low)) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 12812db..042754b 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6169,6 +6169,8 @@ bool kvm_vcpu_compatible(struct kvm_vcpu *vcpu) return irqchip_in_kernel(vcpu->kvm) == (vcpu->arch.apic != NULL); } +struct static_key kvm_no_apic_vcpu __read_mostly; + int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) { struct page *page; @@ -6201,7 +6203,8 @@ int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) r = kvm_create_lapic(vcpu); if (r < 0) goto fail_mmu_destroy; - } + } else + static_key_slow_inc(&kvm_no_apic_vcpu); vcpu->arch.mce_banks = kzalloc(KVM_MAX_MCE_BANKS * sizeof(u64) * 4, GFP_KERNEL); @@ -6241,6 +6244,8 @@ void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) kvm_mmu_destroy(vcpu); srcu_read_unlock(&vcpu->kvm->srcu, idx); free_page((unsigned long)vcpu->arch.pio_data); + if (!irqchip_in_kernel(vcpu->kvm)) + static_key_slow_dec(&kvm_no_apic_vcpu); } int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 3d1134d..2b5219c 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -124,4 +124,5 @@ int kvm_write_guest_virt_system(struct x86_emulate_ctxt *ctxt, extern u64 host_xcr0; +extern struct static_key kvm_no_apic_vcpu; #endif