summaryrefslogtreecommitdiff
path: root/drivers
diff options
context:
space:
mode:
Diffstat (limited to 'drivers')
-rw-r--r--drivers/net/virtio_net.c22
1 files changed, 17 insertions, 5 deletions
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 156d76fee16..4452306d532 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -44,6 +44,7 @@ struct virtnet_info
/* The skb we couldn't send because buffers were full. */
struct sk_buff *last_xmit_skb;
+ /* If we need to free in a timer, this is it. */
struct timer_list xmit_free_timer;
/* Number of input buffers, and max we've ever had. */
@@ -51,6 +52,7 @@ struct virtnet_info
/* For cleaning up after transmission. */
struct tasklet_struct tasklet;
+ bool free_in_tasklet;
/* Receive & send queues. */
struct sk_buff_head recv;
@@ -74,7 +76,7 @@ static void skb_xmit_done(struct virtqueue *svq)
/* Suppress further interrupts. */
svq->vq_ops->disable_cb(svq);
- /* We were waiting for more output buffers. */
+ /* We were probably waiting for more output buffers. */
netif_wake_queue(vi->dev);
/* Make sure we re-xmit last_xmit_skb: if there are no more packets
@@ -242,6 +244,8 @@ static void free_old_xmit_skbs(struct virtnet_info *vi)
}
}
+/* If the virtio transport doesn't always notify us when all in-flight packets
+ * are consumed, we fall back to using this function on a timer to free them. */
static void xmit_free(unsigned long data)
{
struct virtnet_info *vi = (void *)data;
@@ -302,7 +306,7 @@ static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
- if (!err)
+ if (!err && !vi->free_in_tasklet)
mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
return err;
@@ -317,6 +321,8 @@ static void xmit_tasklet(unsigned long data)
vi->svq->vq_ops->kick(vi->svq);
vi->last_xmit_skb = NULL;
}
+ if (vi->free_in_tasklet)
+ free_old_xmit_skbs(vi);
netif_tx_unlock_bh(vi->dev);
}
@@ -457,6 +463,10 @@ static int virtnet_probe(struct virtio_device *vdev)
vi->vdev = vdev;
vdev->priv = vi;
+ /* If they give us a callback when all buffers are done, we don't need
+ * the timer. */
+ vi->free_in_tasklet = virtio_has_feature(vdev,VIRTIO_F_NOTIFY_ON_EMPTY);
+
/* We expect two virtqueues, receive then send. */
vi->rvq = vdev->config->find_vq(vdev, 0, skb_recv_done);
if (IS_ERR(vi->rvq)) {
@@ -476,7 +486,8 @@ static int virtnet_probe(struct virtio_device *vdev)
tasklet_init(&vi->tasklet, xmit_tasklet, (unsigned long)vi);
- setup_timer(&vi->xmit_free_timer, xmit_free, (unsigned long)vi);
+ if (!vi->free_in_tasklet)
+ setup_timer(&vi->xmit_free_timer, xmit_free, (unsigned long)vi);
err = register_netdev(dev);
if (err) {
@@ -515,7 +526,8 @@ static void virtnet_remove(struct virtio_device *vdev)
/* Stop all the virtqueues. */
vdev->config->reset(vdev);
- del_timer_sync(&vi->xmit_free_timer);
+ if (!vi->free_in_tasklet)
+ del_timer_sync(&vi->xmit_free_timer);
/* Free our skbs in send and recv queues, if any. */
while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
@@ -540,7 +552,7 @@ static struct virtio_device_id id_table[] = {
static unsigned int features[] = {
VIRTIO_NET_F_CSUM, VIRTIO_NET_F_GSO, VIRTIO_NET_F_MAC,
VIRTIO_NET_F_HOST_TSO4, VIRTIO_NET_F_HOST_UFO, VIRTIO_NET_F_HOST_TSO6,
- VIRTIO_NET_F_HOST_ECN,
+ VIRTIO_NET_F_HOST_ECN, VIRTIO_F_NOTIFY_ON_EMPTY,
};
static struct virtio_driver virtio_net = {