net: add netif_tx_queue_frozen_or_stopped

When testing struct netdev_queue state against FROZEN bit, we also test
XOFF bit. We can test both bits at once and save some cycles.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

include/linux/netdevice.h

@@ -493,6 +493,8 @@ static inline void napi_synchronize(const struct napi_struct *n)
 enum netdev_queue_state_t {
 	__QUEUE_STATE_XOFF,
 	__QUEUE_STATE_FROZEN,
+#define QUEUE_STATE_XOFF_OR_FROZEN ((1 << __QUEUE_STATE_XOFF)		| \
+				    (1 << __QUEUE_STATE_FROZEN))
 };
 
 struct netdev_queue {
@@ -1629,9 +1631,9 @@ static inline int netif_queue_stopped(const struct net_device *dev)
 	return netif_tx_queue_stopped(netdev_get_tx_queue(dev, 0));
 }
 
-static inline int netif_tx_queue_frozen(const struct netdev_queue *dev_queue)
+static inline int netif_tx_queue_frozen_or_stopped(const struct netdev_queue *dev_queue)
 {
-	return test_bit(__QUEUE_STATE_FROZEN, &dev_queue->state);
+	return dev_queue->state & QUEUE_STATE_XOFF_OR_FROZEN;
 }
 
 /**

net/core/netpoll.c

@@ -76,8 +76,7 @@ static void queue_process(struct work_struct *work)
 
 		local_irq_save(flags);
 		__netif_tx_lock(txq, smp_processor_id());
-		if (netif_tx_queue_stopped(txq) ||
-		    netif_tx_queue_frozen(txq) ||
+		if (netif_tx_queue_frozen_or_stopped(txq) ||
 		    ops->ndo_start_xmit(skb, dev) != NETDEV_TX_OK) {
 			skb_queue_head(&npinfo->txq, skb);
 			__netif_tx_unlock(txq);

net/core/pktgen.c

@@ -3527,7 +3527,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
 
 	__netif_tx_lock_bh(txq);
 
-	if (unlikely(netif_tx_queue_stopped(txq) || netif_tx_queue_frozen(txq))) {
+	if (unlikely(netif_tx_queue_frozen_or_stopped(txq))) {
 		ret = NETDEV_TX_BUSY;
 		pkt_dev->last_ok = 0;
 		goto unlock;

net/sched/sch_generic.c

@@ -60,8 +60,7 @@ static inline struct sk_buff *dequeue_skb(struct Qdisc *q)
 
 		/* check the reason of requeuing without tx lock first */
 		txq = netdev_get_tx_queue(dev, skb_get_queue_mapping(skb));
-		if (!netif_tx_queue_stopped(txq) &&
-		    !netif_tx_queue_frozen(txq)) {
+		if (!netif_tx_queue_frozen_or_stopped(txq)) {
 			q->gso_skb = NULL;
 			q->q.qlen--;
 		} else
@@ -122,7 +121,7 @@ int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 	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_frozen_or_stopped(txq))
 		ret = dev_hard_start_xmit(skb, dev, txq);
 
 	HARD_TX_UNLOCK(dev, txq);
@@ -144,8 +143,7 @@ int sch_direct_xmit(struct sk_buff *skb, struct Qdisc *q,
 		ret = dev_requeue_skb(skb, q);
 	}
 
-	if (ret && (netif_tx_queue_stopped(txq) ||
-		    netif_tx_queue_frozen(txq)))
+	if (ret && netif_tx_queue_frozen_or_stopped(txq))
 		ret = 0;
 
 	return ret;

net/sched/sch_teql.c

@@ -309,8 +309,7 @@ static netdev_tx_t teql_master_xmit(struct sk_buff *skb, struct net_device *dev)
 			if (__netif_tx_trylock(slave_txq)) {
 				unsigned int length = qdisc_pkt_len(skb);
 
-				if (!netif_tx_queue_stopped(slave_txq) &&
-				    !netif_tx_queue_frozen(slave_txq) &&
+				if (!netif_tx_queue_frozen_or_stopped(slave_txq) &&
 				    slave_ops->ndo_start_xmit(skb, slave) == NETDEV_TX_OK) {
 					txq_trans_update(slave_txq);
 					__netif_tx_unlock(slave_txq);