From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Auger Subject: [PATCH v9 4/5] KVM: arm/arm64: remove coarse grain dist locking at kvm_vgic_sync_hwstate Date: Wed, 4 Mar 2015 11:14:35 +0100 Message-ID: <1425464076-20558-5-git-send-email-eric.auger@linaro.org> References: <1425464076-20558-1-git-send-email-eric.auger@linaro.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 4C6A547959 for ; Wed, 4 Mar 2015 05:11:25 -0500 (EST) Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id YE5x5iOhn6h2 for ; Wed, 4 Mar 2015 05:11:24 -0500 (EST) Received: from mail-wi0-f182.google.com (mail-wi0-f182.google.com [209.85.212.182]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 68D4F47975 for ; Wed, 4 Mar 2015 05:11:24 -0500 (EST) Received: by wibhm9 with SMTP id hm9so6105175wib.2 for ; Wed, 04 Mar 2015 02:17:25 -0800 (PST) In-Reply-To: <1425464076-20558-1-git-send-email-eric.auger@linaro.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu To: eric.auger@st.com, eric.auger@linaro.org, christoffer.dall@linaro.org, marc.zyngier@arm.com, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org Cc: gleb@kernel.org, andre.przywara@arm.com, pbonzini@redhat.com, linux-kernel@vger.kernel.org, patches@linaro.org List-Id: kvmarm@lists.cs.columbia.edu To prepare for irqfd addition, coarse grain locking is removed at kvm_vgic_sync_hwstate level and finer grain locking is introduced in vgic_process_maintenance only. Signed-off-by: Eric Auger Acked-by: Christoffer Dall --- virt/kvm/arm/vgic.c | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-) diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 0cc6ab6..4e9b6d3 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1081,6 +1081,7 @@ epilog: static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) { u32 status = vgic_get_interrupt_status(vcpu); + struct vgic_dist *dist = &vcpu->kvm->arch.vgic; bool level_pending = false; kvm_debug("STATUS = %08x\n", status); @@ -1098,6 +1099,7 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) struct vgic_lr vlr = vgic_get_lr(vcpu, lr); WARN_ON(vgic_irq_is_edge(vcpu, vlr.irq)); + spin_lock(&dist->lock); vgic_irq_clear_queued(vcpu, vlr.irq); WARN_ON(vlr.state & LR_STATE_MASK); vlr.state = 0; @@ -1125,6 +1127,8 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) vgic_cpu_irq_clear(vcpu, vlr.irq); } + spin_unlock(&dist->lock); + /* * Despite being EOIed, the LR may not have * been marked as empty. @@ -1139,10 +1143,7 @@ static bool vgic_process_maintenance(struct kvm_vcpu *vcpu) return level_pending; } -/* - * Sync back the VGIC state after a guest run. The distributor lock is - * needed so we don't get preempted in the middle of the state processing. - */ +/* Sync back the VGIC state after a guest run */ static void __kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) { struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; @@ -1189,14 +1190,10 @@ void kvm_vgic_flush_hwstate(struct kvm_vcpu *vcpu) void kvm_vgic_sync_hwstate(struct kvm_vcpu *vcpu) { - struct vgic_dist *dist = &vcpu->kvm->arch.vgic; - if (!irqchip_in_kernel(vcpu->kvm)) return; - spin_lock(&dist->lock); __kvm_vgic_sync_hwstate(vcpu); - spin_unlock(&dist->lock); } int kvm_vgic_vcpu_pending_irq(struct kvm_vcpu *vcpu) -- 1.9.1