netpoll per device txq

When the netpoll beast got really busy, it tended to clog
things, so it stored them for later. But the beast was putting
all it's skb's in one basket. This was bad because maybe some
pipes were clogged and others were not.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>

1 files changed, 15 insertions, 35 deletions

diff --git a/net/core/netpoll.c b/net/core/netpoll.c
index c66df2f45d2..ac4e8b8f57d 100644
--- a/net/core/netpoll.c
+++ b/net/core/netpoll.c
@@ -38,10 +38,6 @@
 
 static struct sk_buff_head skb_pool;
 
-static DEFINE_SPINLOCK(queue_lock);
-static int queue_depth;
-static struct sk_buff *queue_head, *queue_tail;
-
 static atomic_t trapped;
 
 #define NETPOLL_RX_ENABLED  1
@@ -56,46 +52,25 @@ static void arp_reply(struct sk_buff *skb);
 
 static void queue_process(void *p)
 {
-	unsigned long flags;
+	struct netpoll_info *npinfo = p;
 	struct sk_buff *skb;
 
-	while (queue_head) {
-		spin_lock_irqsave(&queue_lock, flags);
-
-		skb = queue_head;
-		queue_head = skb->next;
-		if (skb == queue_tail)
-			queue_head = NULL;
-
-		queue_depth--;
-
-		spin_unlock_irqrestore(&queue_lock, flags);
-
+	while ((skb = skb_dequeue(&npinfo->txq)))
 		dev_queue_xmit(skb);
-	}
-}
 
-static DECLARE_WORK(send_queue, queue_process, NULL);
+}
 
 void netpoll_queue(struct sk_buff *skb)
 {
-	unsigned long flags;
+	struct net_device *dev = skb->dev;
+	struct netpoll_info *npinfo = dev->npinfo;
 
-	if (queue_depth == MAX_QUEUE_DEPTH) {
-		__kfree_skb(skb);
-		return;
+	if (!npinfo)
+		kfree_skb(skb);
+	else {
+		skb_queue_tail(&npinfo->txq, skb);
+		schedule_work(&npinfo->tx_work);
 	}
-
-	spin_lock_irqsave(&queue_lock, flags);
-	if (!queue_head)
-		queue_head = skb;
-	else
-		queue_tail->next = skb;
-	queue_tail = skb;
-	queue_depth++;
-	spin_unlock_irqrestore(&queue_lock, flags);
-
-	schedule_work(&send_queue);
 }
 
 static int checksum_udp(struct sk_buff *skb, struct udphdr *uh,
@@ -658,6 +633,9 @@ int netpoll_setup(struct netpoll *np)
 		npinfo->tries = MAX_RETRIES;
 		spin_lock_init(&npinfo->rx_lock);
 		skb_queue_head_init(&npinfo->arp_tx);
+		skb_queue_head_init(&npinfo->txq);
+		INIT_WORK(&npinfo->tx_work, queue_process, npinfo);
+
 		atomic_set(&npinfo->refcnt, 1);
 	} else {
 		npinfo = ndev->npinfo;
@@ -780,6 +758,8 @@ void netpoll_cleanup(struct netpoll *np)
 			np->dev->npinfo = NULL;
 			if (atomic_dec_and_test(&npinfo->refcnt)) {
 				skb_queue_purge(&npinfo->arp_tx);
+ 				skb_queue_purge(&npinfo->txq);
+ 				flush_scheduled_work();
 
 				kfree(npinfo);
 			}