Now we can easily use vq->num_free to determine if there are descriptors
left in the queue, we're about to change virtqueue_add_buf() to return 0
on success. The virtio_net driver is the only one which actually uses
the return value, so change that.
Signed-off-by: Rusty Russell <ru...@rustcorp.com.au>
---
drivers/net/virtio_net.c | 33 +++++++++++++--------------------
1 file changed, 13 insertions(+), 20 deletions(-)
diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c
index 6c094c8..7c7f5a9 100644
--- a/drivers/net/virtio_net.c
+++ b/drivers/net/virtio_net.c
@@ -471,10 +471,11 @@ static bool try_fill_recv(struct virtnet_info *vi, gfp_t
gfp)
err = add_recvbuf_small(vi, gfp);
oom = err == -ENOMEM;
- if (err < 0)
+ if (err)
break;
++vi->num;
- } while (err > 0);
+ } while (vi->rvq->num_free);
+
if (unlikely(vi->num > vi->max))
vi->max = vi->num;
virtqueue_kick(vi->rvq);
@@ -625,27 +626,20 @@ static int xmit_skb(struct virtnet_info *vi, struct
sk_buff *skb)
static netdev_tx_t start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct virtnet_info *vi = netdev_priv(dev);
- int capacity;
+ int err;
/* Free up any pending old buffers before queueing new ones. */
free_old_xmit_skbs(vi);
/* Try to transmit */
- capacity = xmit_skb(vi, skb);
+ err = xmit_skb(vi, skb);
- /* This can happen with OOM and indirect buffers. */
- if (unlikely(capacity < 0)) {
- if (likely(capacity == -ENOMEM)) {
- if (net_ratelimit())
- dev_warn(&dev->dev,
- "TX queue failure: out of memory\n");
- } else {
- dev->stats.tx_fifo_errors++;
- if (net_ratelimit())
- dev_warn(&dev->dev,
- "Unexpected TX queue failure: %d\n",
- capacity);
- }
+ /* This should not happen! */
+ if (unlikely(err < 0)) {
+ dev->stats.tx_fifo_errors++;
+ if (net_ratelimit())
+ dev_warn(&dev->dev,
+ "Unexpected TX queue failure: %d\n", err);
dev->stats.tx_dropped++;
kfree_skb(skb);
return NETDEV_TX_OK;
@@ -658,13 +652,12 @@ static netdev_tx_t start_xmit(struct sk_buff *skb, struct
net_device *dev)
/* Apparently nice girls don't return TX_BUSY; stop the queue
* before it gets out of hand. Naturally, this wastes entries. */
- if (capacity < 2+MAX_SKB_FRAGS) {
+ if (vi->svq->num_free < 2+MAX_SKB_FRAGS) {
netif_stop_queue(dev);
if (unlikely(!virtqueue_enable_cb_delayed(vi->svq))) {
/* More just got used, free them then recheck. */
free_old_xmit_skbs(vi);
- capacity = vi->svq->num_free;
- if (capacity >= 2+MAX_SKB_FRAGS) {
+ if (vi->svq->num_free >= 2+MAX_SKB_FRAGS) {
netif_start_queue(dev);
virtqueue_disable_cb(vi->svq);
}
--
1.7.9.5
_______________________________________________
Virtualization mailing list
Virtualization@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/virtualization
