Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753429AbbG3DjO (ORCPT ); Wed, 29 Jul 2015 23:39:14 -0400 Received: from mail-pd0-f181.google.com ([209.85.192.181]:35117 "EHLO mail-pd0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753150AbbG3DjM (ORCPT ); Wed, 29 Jul 2015 23:39:12 -0400 Date: Wed, 29 Jul 2015 20:39:09 -0700 From: Steve Rutherford To: Paolo Bonzini Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, alex.williamson@redhat.com, yang.z.zhang@intel.com, srutherford@intel.com Subject: Re: [PATCH 1/2] KVM: x86: set TMR when the interrupt is accepted Message-ID: <20150730033909.GD15229@google.com> References: <1438177055-26764-1-git-send-email-pbonzini@redhat.com> <1438177055-26764-2-git-send-email-pbonzini@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1438177055-26764-2-git-send-email-pbonzini@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5615 Lines: 148 On Wed, Jul 29, 2015 at 03:37:34PM +0200, Paolo Bonzini wrote: > Do not compute TMR in advance. Instead, set the TMR just before the interrupt > is accepted into the IRR. This limits the coupling between IOAPIC and LAPIC. > > Signed-off-by: Paolo Bonzini > --- > arch/x86/kvm/ioapic.c | 9 ++------- > arch/x86/kvm/ioapic.h | 3 +-- > arch/x86/kvm/lapic.c | 19 ++++++++++--------- > arch/x86/kvm/lapic.h | 1 - > arch/x86/kvm/x86.c | 5 +---- > 5 files changed, 14 insertions(+), 23 deletions(-) > > diff --git a/arch/x86/kvm/ioapic.c b/arch/x86/kvm/ioapic.c > index 856f79105bb5..eaf4ec38d980 100644 > --- a/arch/x86/kvm/ioapic.c > +++ b/arch/x86/kvm/ioapic.c > @@ -246,8 +246,7 @@ static void update_handled_vectors(struct kvm_ioapic *ioapic) > smp_wmb(); > } > > -void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap, > - u32 *tmr) > +void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap) > { > struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic; > union kvm_ioapic_redirect_entry *e; > @@ -260,13 +259,9 @@ void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap, > kvm_irq_has_notifier(ioapic->kvm, KVM_IRQCHIP_IOAPIC, index) || > index == RTC_GSI) { > if (kvm_apic_match_dest(vcpu, NULL, 0, > - e->fields.dest_id, e->fields.dest_mode)) { > + e->fields.dest_id, e->fields.dest_mode)) > __set_bit(e->fields.vector, > (unsigned long *)eoi_exit_bitmap); > - if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG) > - __set_bit(e->fields.vector, > - (unsigned long *)tmr); > - } > } > } > spin_unlock(&ioapic->lock); > diff --git a/arch/x86/kvm/ioapic.h b/arch/x86/kvm/ioapic.h > index ca0b0b4e6256..3dbd0e2aac4e 100644 > --- a/arch/x86/kvm/ioapic.h > +++ b/arch/x86/kvm/ioapic.h > @@ -120,7 +120,6 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src, > struct kvm_lapic_irq *irq, unsigned long *dest_map); > int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state); > int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state); > -void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap, > - u32 *tmr); > +void kvm_ioapic_scan_entry(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap); > > #endif > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c > index 2a5ca97c263b..9be64c77d6db 100644 > --- a/arch/x86/kvm/lapic.c > +++ b/arch/x86/kvm/lapic.c > @@ -551,15 +551,6 @@ static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu) > __clear_bit(KVM_APIC_PV_EOI_PENDING, &vcpu->arch.apic_attention); > } > > -void kvm_apic_update_tmr(struct kvm_vcpu *vcpu, u32 *tmr) > -{ > - struct kvm_lapic *apic = vcpu->arch.apic; > - int i; > - > - for (i = 0; i < 8; i++) > - apic_set_reg(apic, APIC_TMR + 0x10 * i, tmr[i]); > -} > - > static void apic_update_ppr(struct kvm_lapic *apic) > { > u32 tpr, isrv, ppr, old_ppr; > @@ -781,6 +772,9 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode, > case APIC_DM_LOWEST: > vcpu->arch.apic_arb_prio++; > case APIC_DM_FIXED: > + if (unlikely(trig_mode && !level)) > + break; > + > /* FIXME add logic for vcpu on reset */ > if (unlikely(!apic_enabled(apic))) > break; > @@ -790,6 +784,13 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode, > if (dest_map) > __set_bit(vcpu->vcpu_id, dest_map); > > + if (apic_test_vector(vector, apic->regs + APIC_TMR) != !!trig_mode) { > + if (trig_mode) > + apic_set_vector(vector, apic->regs + APIC_TMR); > + else > + apic_clear_vector(vector, apic->regs + APIC_TMR); > + } > + > if (kvm_x86_ops->deliver_posted_interrupt) > kvm_x86_ops->deliver_posted_interrupt(vcpu, vector); > else { > diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h > index 764037991d26..eb46d6bcaa75 100644 > --- a/arch/x86/kvm/lapic.h > +++ b/arch/x86/kvm/lapic.h > @@ -57,7 +57,6 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value); > u64 kvm_lapic_get_base(struct kvm_vcpu *vcpu); > void kvm_apic_set_version(struct kvm_vcpu *vcpu); > > -void kvm_apic_update_tmr(struct kvm_vcpu *vcpu, u32 *tmr); > void __kvm_apic_update_irr(u32 *pir, void *regs); > void kvm_apic_update_irr(struct kvm_vcpu *vcpu, u32 *pir); > int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq, > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index 23e47a0b054b..48dc954542db 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -6149,17 +6149,14 @@ static void process_smi(struct kvm_vcpu *vcpu) > static void vcpu_scan_ioapic(struct kvm_vcpu *vcpu) > { > u64 eoi_exit_bitmap[4]; > - u32 tmr[8]; > > if (!kvm_apic_hw_enabled(vcpu->arch.apic)) > return; > > memset(eoi_exit_bitmap, 0, 32); > - memset(tmr, 0, 32); > > - kvm_ioapic_scan_entry(vcpu, eoi_exit_bitmap, tmr); > + kvm_ioapic_scan_entry(vcpu, eoi_exit_bitmap); > kvm_x86_ops->load_eoi_exitmap(vcpu, eoi_exit_bitmap); > - kvm_apic_update_tmr(vcpu, tmr); > } > > static void kvm_vcpu_flush_tlb(struct kvm_vcpu *vcpu) > -- > 1.8.3.1 > > > -- > To unsubscribe from this list: send the line "unsubscribe kvm" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Thanks for writing this. This makes TMR handling far cleaner. -- 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/