From patchwork Wed Dec 26 10:52:26 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Michael S. Tsirkin" X-Patchwork-Id: 208161 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 892FB2C00B9 for ; Wed, 26 Dec 2012 22:08:50 +1100 (EST) Received: from localhost ([::1]:40440 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TnoYi-0000Qi-33 for incoming@patchwork.ozlabs.org; Wed, 26 Dec 2012 05:50:00 -0500 Received: from eggs.gnu.org ([208.118.235.92]:52876) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TnoY1-00074c-Jm for qemu-devel@nongnu.org; Wed, 26 Dec 2012 05:49:20 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1TnoXx-0004bk-Sl for qemu-devel@nongnu.org; Wed, 26 Dec 2012 05:49:17 -0500 Received: from mx1.redhat.com ([209.132.183.28]:9333) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1TnoXx-0004bf-L0 for qemu-devel@nongnu.org; Wed, 26 Dec 2012 05:49:13 -0500 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id qBQAnDhc031418 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Wed, 26 Dec 2012 05:49:13 -0500 Received: from redhat.com (vpn1-4-149.ams2.redhat.com [10.36.4.149]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with SMTP id qBQAnA2W015260; Wed, 26 Dec 2012 05:49:11 -0500 Date: Wed, 26 Dec 2012 12:52:26 +0200 From: "Michael S. Tsirkin" To: qemu-devel@nongnu.org, asias@redhat.com, stefanha@redhat.com Message-ID: References: MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: X-Mutt-Fcc: =sent X-Scanned-By: MIMEDefang 2.68 on 10.5.11.25 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Subject: [Qemu-devel] [PATCH 4/8] virtio-pci: cache msix messages X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Some guests mask a vector then unmask without changing it. Store vectors to avoid kvm system calls in this case. Signed-off-by: Michael S. Tsirkin --- hw/virtio-pci.c | 119 ++++++++++++++++++++++++++++++++++++++++++++++---------- hw/virtio-pci.h | 1 + 2 files changed, 100 insertions(+), 20 deletions(-) diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c index 3c258a4..1d77146 100644 --- a/hw/virtio-pci.c +++ b/hw/virtio-pci.c @@ -487,8 +487,6 @@ static int kvm_virtio_pci_vq_vector_use(VirtIOPCIProxy *proxy, unsigned int vector, MSIMessage msg) { - VirtQueue *vq = virtio_get_queue(proxy->vdev, queue_no); - EventNotifier *n = virtio_queue_get_guest_notifier(vq); VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector]; int ret; @@ -500,18 +498,94 @@ static int kvm_virtio_pci_vq_vector_use(VirtIOPCIProxy *proxy, irqfd->virq = ret; } irqfd->users++; + return 0; +} - ret = kvm_irqchip_add_irqfd_notifier(kvm_state, n, irqfd->virq); - if (ret < 0) { - if (--irqfd->users == 0) { - kvm_irqchip_release_virq(kvm_state, irqfd->virq); +static void kvm_virtio_pci_vq_vector_release(VirtIOPCIProxy *proxy, + unsigned int vector) +{ + VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector]; + if (--irqfd->users == 0) { + kvm_irqchip_release_virq(kvm_state, irqfd->virq); + } +} + +static int kvm_virtio_pci_vector_use(VirtIOPCIProxy *proxy, int nvqs) +{ + PCIDevice *dev = &proxy->pci_dev; + VirtIODevice *vdev = proxy->vdev; + unsigned int vector; + int ret, queue_no; + MSIMessage msg; + + for (queue_no = 0; queue_no < nvqs; queue_no++) { + if (!virtio_queue_get_num(vdev, queue_no)) { + break; + } + vector = virtio_queue_vector(vdev, queue_no); + if (vector >= msix_nr_vectors_allocated(dev)) { + continue; + } + msg = msix_get_message(dev, vector); + ret = kvm_virtio_pci_vq_vector_use(proxy, queue_no, vector, msg); + if (ret < 0) { + goto undo; } - return ret; } return 0; + +undo: + while (--queue_no >= 0) { + vector = virtio_queue_vector(vdev, queue_no); + if (vector >= msix_nr_vectors_allocated(dev)) { + continue; + } + kvm_virtio_pci_vq_vector_release(proxy, vector); + } + return ret; } -static void kvm_virtio_pci_vq_vector_release(VirtIOPCIProxy *proxy, +static void kvm_virtio_pci_vector_release(VirtIOPCIProxy *proxy, int nvqs) +{ + PCIDevice *dev = &proxy->pci_dev; + VirtIODevice *vdev = proxy->vdev; + unsigned int vector; + int queue_no; + + for (queue_no = 0; queue_no < nvqs; queue_no++) { + if (!virtio_queue_get_num(vdev, queue_no)) { + break; + } + vector = virtio_queue_vector(vdev, queue_no); + if (vector >= msix_nr_vectors_allocated(dev)) { + continue; + } + kvm_virtio_pci_vq_vector_release(proxy, vector); + } +} + +static int kvm_virtio_pci_vq_vector_unmask(VirtIOPCIProxy *proxy, + unsigned int queue_no, + unsigned int vector, + MSIMessage msg) +{ + VirtQueue *vq = virtio_get_queue(proxy->vdev, queue_no); + EventNotifier *n = virtio_queue_get_guest_notifier(vq); + VirtIOIRQFD *irqfd = &proxy->vector_irqfd[vector]; + int ret; + + if (irqfd->msg.data != msg.data || irqfd->msg.address != msg.address) { + ret = kvm_irqchip_update_msi_route(kvm_state, irqfd->virq, msg); + if (ret < 0) { + return ret; + } + } + + ret = kvm_irqchip_add_irqfd_notifier(kvm_state, n, irqfd->virq); + return ret; +} + +static void kvm_virtio_pci_vq_vector_mask(VirtIOPCIProxy *proxy, unsigned int queue_no, unsigned int vector) { @@ -522,13 +596,9 @@ static void kvm_virtio_pci_vq_vector_release(VirtIOPCIProxy *proxy, ret = kvm_irqchip_remove_irqfd_notifier(kvm_state, n, irqfd->virq); assert(ret == 0); - - if (--irqfd->users == 0) { - kvm_irqchip_release_virq(kvm_state, irqfd->virq); - } } -static int kvm_virtio_pci_vector_use(PCIDevice *dev, unsigned vector, +static int kvm_virtio_pci_vector_unmask(PCIDevice *dev, unsigned vector, MSIMessage msg) { VirtIOPCIProxy *proxy = container_of(dev, VirtIOPCIProxy, pci_dev); @@ -542,7 +612,7 @@ static int kvm_virtio_pci_vector_use(PCIDevice *dev, unsigned vector, if (virtio_queue_vector(vdev, queue_no) != vector) { continue; } - ret = kvm_virtio_pci_vq_vector_use(proxy, queue_no, vector, msg); + ret = kvm_virtio_pci_vq_vector_unmask(proxy, queue_no, vector, msg); if (ret < 0) { goto undo; } @@ -554,12 +624,12 @@ undo: if (virtio_queue_vector(vdev, queue_no) != vector) { continue; } - kvm_virtio_pci_vq_vector_release(proxy, queue_no, vector); + kvm_virtio_pci_vq_vector_mask(proxy, queue_no, vector); } return ret; } -static void kvm_virtio_pci_vector_release(PCIDevice *dev, unsigned vector) +static void kvm_virtio_pci_vector_mask(PCIDevice *dev, unsigned vector) { VirtIOPCIProxy *proxy = container_of(dev, VirtIOPCIProxy, pci_dev); VirtIODevice *vdev = proxy->vdev; @@ -572,7 +642,7 @@ static void kvm_virtio_pci_vector_release(PCIDevice *dev, unsigned vector) if (virtio_queue_vector(vdev, queue_no) != vector) { continue; } - kvm_virtio_pci_vq_vector_release(proxy, queue_no, vector); + kvm_virtio_pci_vq_vector_mask(proxy, queue_no, vector); } } @@ -651,6 +721,7 @@ static int virtio_pci_set_guest_notifiers(DeviceState *d, int nvqs, bool assign) /* Must unset vector notifier while guest notifier is still assigned */ if (proxy->vector_irqfd && !assign) { msix_unset_vector_notifiers(&proxy->pci_dev); + kvm_virtio_pci_vector_release(proxy, nvqs); g_free(proxy->vector_irqfd); proxy->vector_irqfd = NULL; } @@ -672,17 +743,25 @@ static int virtio_pci_set_guest_notifiers(DeviceState *d, int nvqs, bool assign) proxy->vector_irqfd = g_malloc0(sizeof(*proxy->vector_irqfd) * msix_nr_vectors_allocated(&proxy->pci_dev)); + r = kvm_virtio_pci_vector_use(proxy, nvqs); + if (r < 0) { + goto assign_error; + } r = msix_set_vector_notifiers(&proxy->pci_dev, - kvm_virtio_pci_vector_use, - kvm_virtio_pci_vector_release, + kvm_virtio_pci_vector_unmask, + kvm_virtio_pci_vector_mask, kvm_virtio_pci_vector_poll); if (r < 0) { - goto assign_error; + goto notifiers_error; } } return 0; +notifiers_error: + assert(assign); + kvm_virtio_pci_vector_release(proxy, nvqs); + assign_error: /* We get here on assignment failure. Recover by undoing for VQs 0 .. n. */ assert(assign); diff --git a/hw/virtio-pci.h b/hw/virtio-pci.h index b0f17e2..9ff3139 100644 --- a/hw/virtio-pci.h +++ b/hw/virtio-pci.h @@ -27,6 +27,7 @@ #define VIRTIO_PCI_FLAG_USE_IOEVENTFD (1 << VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT) typedef struct { + MSIMessage msg; int virq; unsigned int users; } VirtIOIRQFD;