struct sk_buff_head recv;
struct sk_buff_head send;
+ /* Work struct for refilling if we run low on memory. */
+ struct delayed_work refill;
+
/* Chain pages by the private ptr. */
struct page *pages;
};
dev_kfree_skb(skb);
}
-static void try_fill_recv_maxbufs(struct virtnet_info *vi)
+static bool try_fill_recv_maxbufs(struct virtnet_info *vi, gfp_t gfp)
{
struct sk_buff *skb;
struct scatterlist sg[2+MAX_SKB_FRAGS];
int num, err, i;
+ bool oom = false;
sg_init_table(sg, 2+MAX_SKB_FRAGS);
for (;;) {
struct virtio_net_hdr *hdr;
skb = netdev_alloc_skb(vi->dev, MAX_PACKET_LEN + NET_IP_ALIGN);
- if (unlikely(!skb))
+ if (unlikely(!skb)) {
+ oom = true;
break;
+ }
skb_reserve(skb, NET_IP_ALIGN);
skb_put(skb, MAX_PACKET_LEN);
if (vi->big_packets) {
for (i = 0; i < MAX_SKB_FRAGS; i++) {
skb_frag_t *f = &skb_shinfo(skb)->frags[i];
- f->page = get_a_page(vi, GFP_ATOMIC);
+ f->page = get_a_page(vi, gfp);
if (!f->page)
break;
if (unlikely(vi->num > vi->max))
vi->max = vi->num;
vi->rvq->vq_ops->kick(vi->rvq);
+ return !oom;
}
-static void try_fill_recv(struct virtnet_info *vi)
+/* Returns false if we couldn't fill entirely (OOM). */
+static bool try_fill_recv(struct virtnet_info *vi, gfp_t gfp)
{
struct sk_buff *skb;
struct scatterlist sg[1];
int err;
+ bool oom = false;
- if (!vi->mergeable_rx_bufs) {
- try_fill_recv_maxbufs(vi);
- return;
- }
+ if (!vi->mergeable_rx_bufs)
+ return try_fill_recv_maxbufs(vi, gfp);
for (;;) {
skb_frag_t *f;
skb = netdev_alloc_skb(vi->dev, GOOD_COPY_LEN + NET_IP_ALIGN);
- if (unlikely(!skb))
+ if (unlikely(!skb)) {
+ oom = true;
break;
+ }
skb_reserve(skb, NET_IP_ALIGN);
f = &skb_shinfo(skb)->frags[0];
- f->page = get_a_page(vi, GFP_ATOMIC);
+ f->page = get_a_page(vi, gfp);
if (!f->page) {
+ oom = true;
kfree_skb(skb);
break;
}
if (unlikely(vi->num > vi->max))
vi->max = vi->num;
vi->rvq->vq_ops->kick(vi->rvq);
+ return !oom;
}
static void skb_recv_done(struct virtqueue *rvq)
}
}
+static void refill_work(struct work_struct *work)
+{
+ struct virtnet_info *vi;
+ bool still_empty;
+
+ vi = container_of(work, struct virtnet_info, refill.work);
+ napi_disable(&vi->napi);
+ try_fill_recv(vi, GFP_KERNEL);
+ still_empty = (vi->num == 0);
+ napi_enable(&vi->napi);
+
+ /* In theory, this can happen: if we don't get any buffers in
+ * we will *never* try to fill again. */
+ if (still_empty)
+ schedule_delayed_work(&vi->refill, HZ/2);
+}
+
static int virtnet_poll(struct napi_struct *napi, int budget)
{
struct virtnet_info *vi = container_of(napi, struct virtnet_info, napi);
received++;
}
- /* FIXME: If we oom and completely run out of inbufs, we need
- * to start a timer trying to fill more. */
- if (vi->num < vi->max / 2)
- try_fill_recv(vi);
+ if (vi->num < vi->max / 2) {
+ if (!try_fill_recv(vi, GFP_ATOMIC))
+ schedule_delayed_work(&vi->refill, 0);
+ }
/* Out of packets? */
if (received < budget) {
dev_warn(&dev->dev, "Failed to kill VLAN ID %d.\n", vid);
}
-static struct ethtool_ops virtnet_ethtool_ops = {
+static const struct ethtool_ops virtnet_ethtool_ops = {
.set_tx_csum = virtnet_set_tx_csum,
.set_sg = ethtool_op_set_sg,
.set_tso = ethtool_op_set_tso,
vi->vdev = vdev;
vdev->priv = vi;
vi->pages = NULL;
+ INIT_DELAYED_WORK(&vi->refill, refill_work);
/* If they give us a callback when all buffers are done, we don't need
* the timer. */
}
/* Last of all, set up some receive buffers. */
- try_fill_recv(vi);
+ try_fill_recv(vi, GFP_KERNEL);
/* If we didn't even get one input buffer, we're useless. */
if (vi->num == 0) {
unregister:
unregister_netdev(dev);
+ cancel_delayed_work_sync(&vi->refill);
free_vqs:
vdev->config->del_vqs(vdev);
free:
BUG_ON(vi->num != 0);
unregister_netdev(vi->dev);
+ cancel_delayed_work_sync(&vi->refill);
vdev->config->del_vqs(vi->vdev);