Each time we re-fill the recv queue with buffers, we allocate
one too many skbs and free it again when adding fails. We should
recycle the pages allocated in this case.
A previous version of this patch made trim_pages() trim trailing
unused pages from skbs with some paged data, but this actually
caused a barely measurable slowdown.
Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> (use netdev_priv)
Signed-off-by: David S. Miller <davem@davemloft.net>
+static void trim_pages(struct virtnet_info *vi, struct sk_buff *skb)
+{
+ unsigned int i;
+
+ for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
+ give_a_page(vi, skb_shinfo(skb)->frags[i].page);
+ skb_shinfo(skb)->nr_frags = 0;
+ skb->data_len = 0;
+}
+
static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask)
{
struct page *p = vi->pages;
static struct page *get_a_page(struct virtnet_info *vi, gfp_t gfp_mask)
{
struct page *p = vi->pages;
}
len -= sizeof(struct virtio_net_hdr);
}
len -= sizeof(struct virtio_net_hdr);
- if (len <= MAX_PACKET_LEN) {
- unsigned int i;
-
- for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
- give_a_page(netdev_priv(dev),
- skb_shinfo(skb)->frags[i].page);
- skb->data_len = 0;
- skb_shinfo(skb)->nr_frags = 0;
- }
+ if (len <= MAX_PACKET_LEN)
+ trim_pages(netdev_priv(dev), skb);
err = pskb_trim(skb, len);
if (err) {
err = pskb_trim(skb, len);
if (err) {
err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
if (err) {
skb_unlink(skb, &vi->recv);
err = vi->rvq->vq_ops->add_buf(vi->rvq, sg, 0, num, skb);
if (err) {
skb_unlink(skb, &vi->recv);