virtio: virtio_net free transmit skbs in a timer

[deliverable/linux.git] / drivers / net / virtio_net.c

diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 9a3b85e55ccc4fa62c671b7f3dc7835e225e6e7a..156d76fee1646de6f3260d176f300218734dc246 100644 (file)
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -44,6 +44,8 @@ struct virtnet_info
        /* The skb we couldn't send because buffers were full. */
        struct sk_buff *last_xmit_skb;
 
+       struct timer_list xmit_free_timer;
+
        /* Number of input buffers, and max we've ever had. */
        unsigned int num, max;
 
@@ -240,9 +242,23 @@ static void free_old_xmit_skbs(struct virtnet_info *vi)
        }
 }
 
+static void xmit_free(unsigned long data)
+{
+       struct virtnet_info *vi = (void *)data;
+
+       netif_tx_lock(vi->dev);
+
+       free_old_xmit_skbs(vi);
+
+       if (!skb_queue_empty(&vi->send))
+               mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
+
+       netif_tx_unlock(vi->dev);
+}
+
 static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
 {
-       int num;
+       int num, err;
        struct scatterlist sg[2+MAX_SKB_FRAGS];
        struct virtio_net_hdr *hdr;
        const unsigned char *dest = ((struct ethhdr *)skb->data)->h_dest;
@@ -285,7 +301,11 @@ static int xmit_skb(struct virtnet_info *vi, struct sk_buff *skb)
        vnet_hdr_to_sg(sg, skb);
        num = skb_to_sgvec(skb, sg+1, 0, skb->len) + 1;
 
-       return vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
+       err = vi->svq->vq_ops->add_buf(vi->svq, sg, num, 0, skb);
+       if (!err)
+               mod_timer(&vi->xmit_free_timer, jiffies + (HZ/10));
+
+       return err;
 }
 
 static void xmit_tasklet(unsigned long data)
@@ -456,6 +476,8 @@ 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);
+
        err = register_netdev(dev);
        if (err) {
                pr_debug("virtio_net: registering device failed\n");
@@ -493,6 +515,8 @@ static void virtnet_remove(struct virtio_device *vdev)
        /* Stop all the virtqueues. */
        vdev->config->reset(vdev);
 
+       del_timer_sync(&vi->xmit_free_timer);
+
        /* Free our skbs in send and recv queues, if any. */
        while ((skb = __skb_dequeue(&vi->recv)) != NULL) {
                kfree_skb(skb);