qemu/hw/virtio/virtio-net-pci.c
Jason Wang 51a81a2118 virtio-net: calculating proper msix vectors on init
Currently, the default msix vectors for virtio-net-pci is 3 which is
obvious not suitable for multiqueue guest, so we depends on the user
or management tools to pass a correct vectors parameter. In fact, we
can simplifying this by calculating the number of vectors on realize.

Consider we have N queues, the number of vectors needed is 2*N + 2
(#queue pairs + plus one config interrupt and control vq). We didn't
check whether or not host support control vq because it was added
unconditionally by qemu to avoid breaking legacy guests such as Minix.

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2021-03-15 16:41:22 +08:00

109 lines
3.3 KiB
C

/*
* Virtio net PCI Bindings
*
* Copyright IBM, Corp. 2007
* Copyright (c) 2009 CodeSourcery
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
* Paul Brook <paul@codesourcery.com>
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
* Contributions after 2012-01-13 are licensed under the terms of the
* GNU GPL, version 2 or (at your option) any later version.
*/
#include "qemu/osdep.h"
#include "hw/qdev-properties.h"
#include "hw/virtio/virtio-net.h"
#include "virtio-pci.h"
#include "qapi/error.h"
#include "qemu/module.h"
#include "qom/object.h"
typedef struct VirtIONetPCI VirtIONetPCI;
/*
* virtio-net-pci: This extends VirtioPCIProxy.
*/
#define TYPE_VIRTIO_NET_PCI "virtio-net-pci-base"
DECLARE_INSTANCE_CHECKER(VirtIONetPCI, VIRTIO_NET_PCI,
TYPE_VIRTIO_NET_PCI)
struct VirtIONetPCI {
VirtIOPCIProxy parent_obj;
VirtIONet vdev;
};
static Property virtio_net_properties[] = {
DEFINE_PROP_BIT("ioeventfd", VirtIOPCIProxy, flags,
VIRTIO_PCI_FLAG_USE_IOEVENTFD_BIT, true),
DEFINE_PROP_UINT32("vectors", VirtIOPCIProxy, nvectors,
DEV_NVECTORS_UNSPECIFIED),
DEFINE_PROP_END_OF_LIST(),
};
static void virtio_net_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
{
DeviceState *qdev = DEVICE(vpci_dev);
VirtIONetPCI *dev = VIRTIO_NET_PCI(vpci_dev);
DeviceState *vdev = DEVICE(&dev->vdev);
VirtIONet *net = VIRTIO_NET(vdev);
if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) {
vpci_dev->nvectors = 2 * MAX(net->nic_conf.peers.queues, 1)
+ 1 /* Config interrupt */
+ 1 /* Control vq */;
}
virtio_net_set_netclient_name(&dev->vdev, qdev->id,
object_get_typename(OBJECT(qdev)));
qdev_realize(vdev, BUS(&vpci_dev->bus), errp);
}
static void virtio_net_pci_class_init(ObjectClass *klass, void *data)
{
DeviceClass *dc = DEVICE_CLASS(klass);
PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
VirtioPCIClass *vpciklass = VIRTIO_PCI_CLASS(klass);
k->romfile = "efi-virtio.rom";
k->vendor_id = PCI_VENDOR_ID_REDHAT_QUMRANET;
k->device_id = PCI_DEVICE_ID_VIRTIO_NET;
k->revision = VIRTIO_PCI_ABI_VERSION;
k->class_id = PCI_CLASS_NETWORK_ETHERNET;
set_bit(DEVICE_CATEGORY_NETWORK, dc->categories);
device_class_set_props(dc, virtio_net_properties);
vpciklass->realize = virtio_net_pci_realize;
}
static void virtio_net_pci_instance_init(Object *obj)
{
VirtIONetPCI *dev = VIRTIO_NET_PCI(obj);
virtio_instance_init_common(obj, &dev->vdev, sizeof(dev->vdev),
TYPE_VIRTIO_NET);
object_property_add_alias(obj, "bootindex", OBJECT(&dev->vdev),
"bootindex");
}
static const VirtioPCIDeviceTypeInfo virtio_net_pci_info = {
.base_name = TYPE_VIRTIO_NET_PCI,
.generic_name = "virtio-net-pci",
.transitional_name = "virtio-net-pci-transitional",
.non_transitional_name = "virtio-net-pci-non-transitional",
.instance_size = sizeof(VirtIONetPCI),
.instance_init = virtio_net_pci_instance_init,
.class_init = virtio_net_pci_class_init,
};
static void virtio_net_pci_register(void)
{
virtio_pci_types_register(&virtio_net_pci_info);
}
type_init(virtio_net_pci_register)