From patchwork Mon Aug 24 12:06:23 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gleb Natapov X-Patchwork-Id: 43604 Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by demeter.kernel.org (8.14.2/8.14.2) with ESMTP id n7OC6U6f025813 for ; Mon, 24 Aug 2009 12:06:30 GMT Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752222AbZHXMGY (ORCPT ); Mon, 24 Aug 2009 08:06:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752009AbZHXMGY (ORCPT ); Mon, 24 Aug 2009 08:06:24 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50476 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751850AbZHXMGY (ORCPT ); Mon, 24 Aug 2009 08:06:24 -0400 Received: from int-mx07.intmail.prod.int.phx2.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.20]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id n7OC6Pdf004077 for ; Mon, 24 Aug 2009 08:06:25 -0400 Received: from dhcp-1-237.tlv.redhat.com (dhcp-1-237.tlv.redhat.com [10.35.1.237]) by int-mx07.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id n7OC6NLV001770; Mon, 24 Aug 2009 08:06:24 -0400 Received: by dhcp-1-237.tlv.redhat.com (Postfix, from userid 13519) id 2DDE718D467; Mon, 24 Aug 2009 15:06:23 +0300 (IDT) Date: Mon, 24 Aug 2009 15:06:23 +0300 From: Gleb Natapov To: kvm@vger.kernel.org Cc: avi@redhat.com, mtosatti@redhat.com Subject: [PATCH][RFC] Use return value from kvm_set_irq() to re-inject PIT interrupts. Message-ID: <20090824120623.GC30093@redhat.com> MIME-Version: 1.0 Content-Disposition: inline X-Scanned-By: MIMEDefang 2.67 on 10.5.11.20 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Use return value from kvm_set_irq() to track coalesced PIT interrupts instead of ack/mask notifiers. Signed-off-by: Gleb Natapov --- Gleb. -- 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 diff --git a/arch/x86/kvm/i8254.c b/arch/x86/kvm/i8254.c index b857ca3..0b63991 100644 --- a/arch/x86/kvm/i8254.c +++ b/arch/x86/kvm/i8254.c @@ -231,20 +231,7 @@ int pit_has_pending_timer(struct kvm_vcpu *vcpu) { struct kvm_pit *pit = vcpu->kvm->arch.vpit; - if (pit && kvm_vcpu_is_bsp(vcpu) && pit->pit_state.irq_ack) - return atomic_read(&pit->pit_state.pit_timer.pending); - return 0; -} - -static void kvm_pit_ack_irq(struct kvm_irq_ack_notifier *kian) -{ - struct kvm_kpit_state *ps = container_of(kian, struct kvm_kpit_state, - irq_ack_notifier); - spin_lock(&ps->inject_lock); - if (atomic_dec_return(&ps->pit_timer.pending) < 0) - atomic_inc(&ps->pit_timer.pending); - ps->irq_ack = 1; - spin_unlock(&ps->inject_lock); + return atomic_read(&pit->pit_state.pit_timer.pending); } void __kvm_migrate_pit_timer(struct kvm_vcpu *vcpu) @@ -297,7 +284,6 @@ static void create_pit_timer(struct kvm_kpit_state *ps, u32 val, int is_period) pt->vcpu = pt->kvm->bsp_vcpu; atomic_set(&pt->pending, 0); - ps->irq_ack = 1; hrtimer_start(&pt->timer, ktime_add_ns(ktime_get(), interval), HRTIMER_MODE_ABS); @@ -577,17 +563,6 @@ void kvm_pit_reset(struct kvm_pit *pit) mutex_unlock(&pit->pit_state.lock); atomic_set(&pit->pit_state.pit_timer.pending, 0); - pit->pit_state.irq_ack = 1; -} - -static void pit_mask_notifer(struct kvm_irq_mask_notifier *kimn, bool mask) -{ - struct kvm_pit *pit = container_of(kimn, struct kvm_pit, mask_notifier); - - if (!mask) { - atomic_set(&pit->pit_state.pit_timer.pending, 0); - pit->pit_state.irq_ack = 1; - } } static const struct kvm_io_device_ops pit_dev_ops = { @@ -619,7 +594,6 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) mutex_init(&pit->pit_state.lock); mutex_lock(&pit->pit_state.lock); - spin_lock_init(&pit->pit_state.inject_lock); kvm->arch.vpit = pit; pit->kvm = kvm; @@ -628,17 +602,11 @@ struct kvm_pit *kvm_create_pit(struct kvm *kvm, u32 flags) pit_state->pit = pit; hrtimer_init(&pit_state->pit_timer.timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS); - pit_state->irq_ack_notifier.gsi = 0; - pit_state->irq_ack_notifier.irq_acked = kvm_pit_ack_irq; - kvm_register_irq_ack_notifier(kvm, &pit_state->irq_ack_notifier); pit_state->pit_timer.reinject = true; mutex_unlock(&pit->pit_state.lock); kvm_pit_reset(pit); - pit->mask_notifier.func = pit_mask_notifer; - kvm_register_irq_mask_notifier(kvm, 0, &pit->mask_notifier); - kvm_iodevice_init(&pit->dev, &pit_dev_ops); ret = __kvm_io_bus_register_dev(&kvm->pio_bus, &pit->dev); if (ret < 0) @@ -670,10 +638,6 @@ void kvm_free_pit(struct kvm *kvm) struct hrtimer *timer; if (kvm->arch.vpit) { - kvm_unregister_irq_mask_notifier(kvm, 0, - &kvm->arch.vpit->mask_notifier); - kvm_unregister_irq_ack_notifier(kvm, - &kvm->arch.vpit->pit_state.irq_ack_notifier); mutex_lock(&kvm->arch.vpit->pit_state.lock); timer = &kvm->arch.vpit->pit_state.pit_timer.timer; hrtimer_cancel(timer); @@ -683,12 +647,12 @@ void kvm_free_pit(struct kvm *kvm) } } -static void __inject_pit_timer_intr(struct kvm *kvm) +static int __inject_pit_timer_intr(struct kvm *kvm) { struct kvm_vcpu *vcpu; - int i; + int i, r; - kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1); + r = kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 1); kvm_set_irq(kvm, kvm->arch.vpit->irq_source_id, 0, 0); /* @@ -703,6 +667,8 @@ static void __inject_pit_timer_intr(struct kvm *kvm) if (kvm->arch.vapics_in_nmi_mode > 0) kvm_for_each_vcpu(i, vcpu, kvm) kvm_apic_nmi_wd_deliver(vcpu); + + return r; } void kvm_inject_pit_timer_irqs(struct kvm_vcpu *vcpu) @@ -711,20 +677,14 @@ void kvm_inject_pit_timer_irqs(struct kvm_vcpu *vcpu) struct kvm *kvm = vcpu->kvm; struct kvm_kpit_state *ps; - if (pit) { - int inject = 0; - ps = &pit->pit_state; - - /* Try to inject pending interrupts when - * last one has been acked. - */ - spin_lock(&ps->inject_lock); - if (atomic_read(&ps->pit_timer.pending) && ps->irq_ack) { - ps->irq_ack = 0; - inject = 1; - } - spin_unlock(&ps->inject_lock); - if (inject) - __inject_pit_timer_intr(kvm); - } + if (!pit) + return; + + ps = &pit->pit_state; + + if (!atomic_read(&ps->pit_timer.pending)) + return; + + if (__inject_pit_timer_intr(kvm)) + atomic_dec(&ps->pit_timer.pending); } diff --git a/arch/x86/kvm/i8254.h b/arch/x86/kvm/i8254.h index d4c1c7f..19937da 100644 --- a/arch/x86/kvm/i8254.h +++ b/arch/x86/kvm/i8254.h @@ -28,8 +28,6 @@ struct kvm_kpit_state { struct mutex lock; struct kvm_pit *pit; spinlock_t inject_lock; - unsigned long irq_ack; - struct kvm_irq_ack_notifier irq_ack_notifier; }; struct kvm_pit { @@ -39,7 +37,6 @@ struct kvm_pit { struct kvm *kvm; struct kvm_kpit_state pit_state; int irq_source_id; - struct kvm_irq_mask_notifier mask_notifier; }; #define KVM_PIT_BASE_ADDRESS 0x40