From patchwork Thu Sep 26 19:01:30 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoffer Dall X-Patchwork-Id: 2950941 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 57F2E9F289 for ; Thu, 26 Sep 2013 19:07:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id CD944202EB for ; Thu, 26 Sep 2013 19:07:55 +0000 (UTC) Received: from casper.infradead.org (casper.infradead.org [85.118.1.10]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 1BF4E201E9 for ; Thu, 26 Sep 2013 19:07:52 +0000 (UTC) Received: from merlin.infradead.org ([2001:4978:20e::2]) by casper.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VPGui-0003mN-Aa; Thu, 26 Sep 2013 19:07:48 +0000 Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1VPGuf-0000Pm-Rw; Thu, 26 Sep 2013 19:07:45 +0000 Received: from mail-pb0-f47.google.com ([209.85.160.47]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VPGua-0000PN-T4 for linux-arm-kernel@lists.infradead.org; Thu, 26 Sep 2013 19:07:44 +0000 Received: by mail-pb0-f47.google.com with SMTP id rr4so1534973pbb.34 for ; Thu, 26 Sep 2013 12:07:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=FXuARIGidSc4aPQnYjjqijtmjhdPU4HlRfKna7ntV5o=; b=aPUu/ctjj1tVS+jlmInPpqs/Q5RNOim8xA8zXhODF6PWR+Kt/z+rswTddb6oDWjzqw de8qM5wWbkAnzLx8YA5bpc8Ksv3dROMMWC8EtvV2EU7oF8S3ZHZrLs0pTDVWsXhA1imC pii8moKBS7LHn2XpqRCkkXjyTTg9wKeK/hIugnSuJQjGpnoLBf+umKaz/pI1OUcEb2YH fYUW6+om45gPUfCi9C8lkKAD5ePS+Qso6ysjGBeGT0fC/+3tTrp3SLbzvmPsUm2OnKVU xGKCoWvg9qLGgZdEFNpD/VJwzH99JzHZJNmse530pY3iUJTWDGh5ocN+7LFxzO6c3rk2 5Xwg== X-Gm-Message-State: ALoCoQlWp/kRzS2gEle5shCyV2ZKshVuDuVLfa8nApU2o7I6YmzDUB4eTa4346b75Df3Wti6lRER X-Received: by 10.66.148.97 with SMTP id tr1mr6985173pab.163.1380222092683; Thu, 26 Sep 2013 12:01:32 -0700 (PDT) Received: from localhost.localdomain (c-67-169-181-221.hsd1.ca.comcast.net. [67.169.181.221]) by mx.google.com with ESMTPSA id k4sm3870767pbd.11.1969.12.31.16.00.00 (version=TLSv1.1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Thu, 26 Sep 2013 12:01:31 -0700 (PDT) From: Christoffer Dall To: kvmarm@lists.cs.columbia.edu Subject: [PATCH v2 1/8] ARM: KVM: Allow creating the VGIC after VCPUs Date: Thu, 26 Sep 2013 12:01:30 -0700 Message-Id: <1380222097-20251-2-git-send-email-christoffer.dall@linaro.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1380222097-20251-1-git-send-email-christoffer.dall@linaro.org> References: <1380222097-20251-1-git-send-email-christoffer.dall@linaro.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20130926_150741_029874_6F022E2E X-CRM114-Status: GOOD ( 19.87 ) X-Spam-Score: -0.1 (/) Cc: Christoffer Dall , linaro-kernel@lists.linaro.org, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, patches@linaro.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.1 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD, SUSPICIOUS_RECIPS, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Rework the VGIC initialization slightly to allow initialization of the vgic cpu-specific state even if the irqchip (the VGIC) hasn't been created by user space yet. This is safe, because the vgic data structures are already allocated when the CPU is allocated if VGIC support is compiled into the kernel. Further, the init process does not depend on any other information and the sacrifice is a slight performance degradation for creating VMs in the no-VGIC case. The reason is that the new device control API doesn't mandate creating the VGIC before creating the VCPU and it is unreasonable to require user space to create the VGIC before creating the VCPUs. At the same time move the irqchip_in_kernel check out of kvm_vcpu_first_run_init and into the init function to make the per-vcpu and global init functions symmetric and add comments on the exported functions making it a bit easier to understand the init flow by only looking at vgic.c. Signed-off-by: Christoffer Dall Reviewed-by: Alexander Graf --- arch/arm/kvm/arm.c | 7 ++++--- virt/kvm/arm/vgic.c | 22 +++++++++++++++++++--- 2 files changed, 23 insertions(+), 6 deletions(-) diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 9c697db..2b1091a 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -461,6 +461,8 @@ static void update_vttbr(struct kvm *kvm) static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) { + int ret; + if (likely(vcpu->arch.has_run_once)) return 0; @@ -470,9 +472,8 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) * Initialize the VGIC before running a vcpu the first time on * this VM. */ - if (irqchip_in_kernel(vcpu->kvm) && - unlikely(!vgic_initialized(vcpu->kvm))) { - int ret = kvm_vgic_init(vcpu->kvm); + if (unlikely(!vgic_initialized(vcpu->kvm))) { + ret = kvm_vgic_init(vcpu->kvm); if (ret) return ret; } diff --git a/virt/kvm/arm/vgic.c b/virt/kvm/arm/vgic.c index 685fc72..5ce100f 100644 --- a/virt/kvm/arm/vgic.c +++ b/virt/kvm/arm/vgic.c @@ -1243,15 +1243,19 @@ static irqreturn_t vgic_maintenance_handler(int irq, void *data) return IRQ_HANDLED; } +/** + * kvm_vgic_vcpu_init - Initialize per-vcpu VGIC state + * @vcpu: pointer to the vcpu struct + * + * Initialize the vgic_cpu struct and vgic_dist struct fields pertaining to + * this vcpu and enable the VGIC for this VCPU + */ int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu) { struct vgic_cpu *vgic_cpu = &vcpu->arch.vgic_cpu; struct vgic_dist *dist = &vcpu->kvm->arch.vgic; int i; - if (!irqchip_in_kernel(vcpu->kvm)) - return 0; - if (vcpu->vcpu_id >= VGIC_MAX_CPUS) return -EBUSY; @@ -1383,10 +1387,22 @@ out: return ret; } +/** + * kvm_vgic_init - Initialize global VGIC state before running any VCPUs + * @kvm: pointer to the kvm struct + * + * Map the virtual CPU interface into the VM before running any VCPUs. We + * can't do this at creation time, because user space must first set the + * virtual CPU interface address in the guest physical address space. Also + * initialize the ITARGETSRn regs to 0 on the emulated distributor. + */ int kvm_vgic_init(struct kvm *kvm) { int ret = 0, i; + if (!irqchip_in_kernel(kvm)) + return 0; + mutex_lock(&kvm->lock); if (vgic_initialized(kvm))