net: Optimize hard_start_xmit() return checking
Recent changes in the TX error propagation require additional checking
and masking of values returned from hard_start_xmit(), mainly to
separate cases where skb was consumed. This aim can be simplified by
changing the order of NETDEV_TX and NET_XMIT codes, because the latter
are treated similarly to negative (ERRNO) values.
After this change much simpler dev_xmit_complete() is also used in
sch_direct_xmit(), so it is moved to netdevice.h.
Additionally NET_RX definitions in netdevice.h are moved up from
between TX codes to avoid confusion while reading the TX comment.
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index b13821a..5173c1e 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -119,39 +119,26 @@
spin_unlock(root_lock);
HARD_TX_LOCK(dev, txq, smp_processor_id());
- if (!netif_tx_queue_stopped(txq) &&
- !netif_tx_queue_frozen(txq)) {
+ if (!netif_tx_queue_stopped(txq) && !netif_tx_queue_frozen(txq))
ret = dev_hard_start_xmit(skb, dev, txq);
- /* an error implies that the skb was consumed */
- if (ret < 0)
- ret = NETDEV_TX_OK;
- /* all NET_XMIT codes map to NETDEV_TX_OK */
- ret &= ~NET_XMIT_MASK;
- }
HARD_TX_UNLOCK(dev, txq);
spin_lock(root_lock);
- switch (ret) {
- case NETDEV_TX_OK:
- /* Driver sent out skb successfully */
+ if (dev_xmit_complete(ret)) {
+ /* Driver sent out skb successfully or skb was consumed */
ret = qdisc_qlen(q);
- break;
-
- case NETDEV_TX_LOCKED:
+ } else if (ret == NETDEV_TX_LOCKED) {
/* Driver try lock failed */
ret = handle_dev_cpu_collision(skb, txq, q);
- break;
-
- default:
+ } else {
/* Driver returned NETDEV_TX_BUSY - requeue skb */
if (unlikely (ret != NETDEV_TX_BUSY && net_ratelimit()))
printk(KERN_WARNING "BUG %s code %d qlen %d\n",
dev->name, ret, q->q.qlen);
ret = dev_requeue_skb(skb, q);
- break;
}
if (ret && (netif_tx_queue_stopped(txq) ||