@@ -2908,6 +2908,11 @@ static inline void netif_tx_unlock_bh(struct net_device *dev)
} \
}
+#define HARD_TX_TRYLOCK(dev, txq) \
+ (((dev->features & NETIF_F_LLTX) == 0) ? \
+ __netif_tx_trylock(txq) : \
+ true )
+
#define HARD_TX_UNLOCK(dev, txq) { \
if ((dev->features & NETIF_F_LLTX) == 0) { \
__netif_tx_unlock(txq); \
@@ -119,17 +119,17 @@ static void queue_process(struct work_struct *work)
txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
local_irq_save(flags);
- __netif_tx_lock(txq, smp_processor_id());
+ HARD_TX_LOCK(dev, txq, smp_processor_id());
if (netif_xmit_frozen_or_stopped(txq) ||
netpoll_start_xmit(skb, dev, txq) != NETDEV_TX_OK) {
skb_queue_head(&npinfo->txq, skb);
- __netif_tx_unlock(txq);
+ HARD_TX_UNLOCK(dev, txq);
local_irq_restore(flags);
schedule_delayed_work(&npinfo->tx_work, HZ/10);
return;
}
- __netif_tx_unlock(txq);
+ HARD_TX_UNLOCK(dev, txq);
local_irq_restore(flags);
}
}
@@ -345,11 +345,11 @@ void netpoll_send_skb_on_dev(struct netpoll *np, struct sk_buff *skb,
/* try until next clock tick */
for (tries = jiffies_to_usecs(1)/USEC_PER_POLL;
tries > 0; --tries) {
- if (__netif_tx_trylock(txq)) {
+ if (HARD_TX_TRYLOCK(dev, txq)) {
if (!netif_xmit_stopped(txq))
status = netpoll_start_xmit(skb, dev, txq);
- __netif_tx_unlock(txq);
+ HARD_TX_UNLOCK(dev, txq);
if (status == NETDEV_TX_OK)
break;
Stop taking the transmit lock when a network device has specified NETIF_F_LLTX. If no locks needed to trasnmit a packet this is the ideal scenario for netpoll as all packets can be trasnmitted immediately. Even if some locks are needed in ndo_start_xmit skipping any unnecessary serialization is desirable for netpoll as it makes it more likely a debugging packet may be trasnmitted immediately instead of being deferred until later. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> --- include/linux/netdevice.h | 5 +++++ net/core/netpoll.c | 10 +++++----- 2 files changed, 10 insertions(+), 5 deletions(-)