We don't need to go from vq to vq info on
data path, so using direct vq->priv pointer for that
seems like a waste.
Let's build an array of vq infos, then we can use vq->index
for that lookup.
Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
---
drivers/virtio/virtio_pci.c | 38 +++++++++++++++++++++++---------------
1 file changed, 23 insertions(+), 15 deletions(-)
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 40b4d47..91b479b 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -47,6 +58,9 @@ struct virtio_pci_device {
spinlock_t lock;
struct list_head virtqueues;
+ /* array of all queues for house-keeping */
+ struct virtio_pci_vq_info **vqs;
+
/* MSI-X support */
int msix_enabled;
int intx_enabled;
@@ -429,7 +432,6 @@ static struct virtqueue *setup_vq(struct virtio_device
*vdev, unsigned index,
goto out_activate_queue;
}
- vq->priv = info;
info->vq = vq;
if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
@@ -449,6 +451,7 @@ static struct virtqueue *setup_vq(struct virtio_device
*vdev, unsigned index,
INIT_LIST_HEAD(&info->node);
}
+ vp_dev->vqs[index] = info;
return vq;
out_assign:
@@ -464,7 +467,7 @@ out_info:
static void vp_del_vq(struct virtqueue *vq)
{
struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
- struct virtio_pci_vq_info *info = vq->priv;
+ struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index];
unsigned int num = vring_get_num(vq);
void *queue = vring_get_pages(vq);
unsigned long flags, size;
@@ -501,7 +504,7 @@ static void vp_del_vqs(struct virtio_device *vdev)
struct virtio_pci_vq_info *info;
list_for_each_entry_safe(vq, n, &vdev->vqs, list) {
- info = vq->priv;
+ info = vp_dev->vqs[vq->index];
if (vp_dev->per_vq_vectors &&
info->msix_vector != VIRTIO_MSI_NO_VECTOR)
free_irq(vp_dev->msix_entries[info->msix_vector].vector,
@@ -511,6 +514,7 @@ static void vp_del_vqs(struct virtio_device *vdev)
vp_dev->per_vq_vectors = false;
vp_free_vectors(vdev);
+ kfree(vp_dev->vqs);
}
static int vp_try_to_find_vqs(struct virtio_device *vdev, unsigned nvqs,
@@ -524,6 +528,10 @@ static int vp_try_to_find_vqs(struct virtio_device *vdev,
unsigned nvqs,
u16 msix_vec;
int i, err, nvectors, allocated_vectors;
+ vp_dev->vqs = kmalloc(nvqs * sizeof *vp_dev->vqs, GFP_KERNEL);
+ if (!vdev->vqs)
+ return -ENOMEM;
+
if (!use_msix) {
/* Old style: one normal interrupt for change and all vqs. */
err = vp_request_intx(vdev);
@@ -628,7 +636,7 @@ static int vp_set_vq_affinity(struct virtqueue *vq, int cpu)
{
struct virtio_device *vdev = vq->vdev;
struct virtio_pci_device *vp_dev = to_vp_device(vdev);
- struct virtio_pci_vq_info *info = vq->priv;
+ struct virtio_pci_vq_info *info = vp_dev->vqs[vq->index];
struct cpumask *mask;
unsigned int irq;
--
MST
Michael S. Tsirkin
2014-Dec-03 16:14 UTC
[PATCH RFC 2/2] virtio_pci: use priv for vq notification
slightly reduce the amount of pointer chasing this needs to do.
More importantly, this will easily generalize to virtio 1.0.
Signed-off-by: Michael S. Tsirkin <mst at redhat.com>
---
drivers/virtio/virtio_pci.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/virtio/virtio_pci.c b/drivers/virtio/virtio_pci.c
index 91b479b..5791a93 100644
--- a/drivers/virtio/virtio_pci.c
+++ b/drivers/virtio/virtio_pci.c
@@ -198,11 +198,9 @@ static void vp_reset(struct virtio_device *vdev)
/* the notify function used when creating a virt queue */
static bool vp_notify(struct virtqueue *vq)
{
- struct virtio_pci_device *vp_dev = to_vp_device(vq->vdev);
-
/* we write the queue's selector into the notification register to
* signal the other end */
- iowrite16(vq->index, vp_dev->ioaddr + VIRTIO_PCI_QUEUE_NOTIFY);
+ iowrite16(vq->index, (void __iomem *)vq->priv);
return true;
}
@@ -432,6 +430,8 @@ static struct virtqueue *setup_vq(struct virtio_device
*vdev, unsigned index,
goto out_activate_queue;
}
+ vq->priv = (void __force *)vp_dev->ioaddr +
+ VIRTIO_PCI_QUEUE_NOTIFY;
info->vq = vq;
if (msix_vec != VIRTIO_MSI_NO_VECTOR) {
--
MST