diff options
| author | Stefan Hajnoczi <stefanha@redhat.com> | 2020-08-18 15:33:46 +0100 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2020-08-27 08:29:13 -0400 |
| commit | 6a558822849fab604a1fcb71e7c4e528cafa21d9 (patch) | |
| tree | baeec7fcfa10f0b0ff3a3290c614453adc0f5e02 /hw/virtio/virtio-scsi-pci.c | |
| parent | 4e5163bd844429711b4d60d51030ab83048d80cd (diff) | |
virtio-scsi-pci: default num_queues to -smp N
Automatically size the number of virtio-scsi-pci, vhost-scsi-pci, and
vhost-user-scsi-pci request virtqueues to match the number of vCPUs.
Other transports continue to default to 1 request virtqueue.
A 1:1 virtqueue:vCPU mapping ensures that completion interrupts are
handled on the same vCPU that submitted the request. No IPI is
necessary to complete an I/O request and performance is improved. The
maximum number of MSI-X vectors and virtqueues limit are respected.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200818143348.310613-6-stefanha@redhat.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'hw/virtio/virtio-scsi-pci.c')
| -rw-r--r-- | hw/virtio/virtio-scsi-pci.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/hw/virtio/virtio-scsi-pci.c b/hw/virtio/virtio-scsi-pci.c index 3ff9eb7ef6..fa4b3bfb50 100644 --- a/hw/virtio/virtio-scsi-pci.c +++ b/hw/virtio/virtio-scsi-pci.c @@ -46,13 +46,17 @@ static void virtio_scsi_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp) { VirtIOSCSIPCI *dev = VIRTIO_SCSI_PCI(vpci_dev); DeviceState *vdev = DEVICE(&dev->vdev); - VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(vdev); DeviceState *proxy = DEVICE(vpci_dev); + VirtIOSCSIConf *conf = &dev->vdev.parent_obj.conf; char *bus_name; + if (conf->num_queues == VIRTIO_SCSI_AUTO_NUM_QUEUES) { + conf->num_queues = + virtio_pci_optimal_num_queues(VIRTIO_SCSI_VQ_NUM_FIXED); + } + if (vpci_dev->nvectors == DEV_NVECTORS_UNSPECIFIED) { - vpci_dev->nvectors = vs->conf.num_queues + - VIRTIO_SCSI_VQ_NUM_FIXED + 1; + vpci_dev->nvectors = conf->num_queues + VIRTIO_SCSI_VQ_NUM_FIXED + 1; } /* |