[NETPOLL]: Don't need rx_flags.

The rx_flags variable is redundant. Turning rx on/off is done
via setting the rx_np pointer.
Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/netpoll.h

@@ -25,7 +25,6 @@ struct netpoll {
 
 struct netpoll_info {
 	atomic_t refcnt;
-	int rx_flags;
 	spinlock_t rx_lock;
 	struct netpoll *rx_np; /* netpoll that registered an rx_hook */
 	struct sk_buff_head arp_tx; /* list of arp requests to reply to */
@@ -51,12 +50,12 @@ static inline int netpoll_rx(struct sk_buff *skb)
 	unsigned long flags;
 	int ret = 0;
 
-	if (!npinfo || (!npinfo->rx_np && !npinfo->rx_flags))
+	if (!npinfo || !npinfo->rx_np)
 		return 0;
 
 	spin_lock_irqsave(&npinfo->rx_lock, flags);
-	/* check rx_flags again with the lock held */
-	if (npinfo->rx_flags && __netpoll_rx(skb))
+	/* check rx_np again with the lock held */
+	if (npinfo->rx_np && __netpoll_rx(skb))
 		ret = 1;
 	spin_unlock_irqrestore(&npinfo->rx_lock, flags);
 

net/core/netpoll.c

@@ -39,7 +39,6 @@ static struct sk_buff_head skb_pool;
 static atomic_t trapped;
 
 #define USEC_PER_POLL	50
-#define NETPOLL_RX_ENABLED  1
 
 #define MAX_SKB_SIZE \
 		(MAX_UDP_CHUNK + sizeof(struct udphdr) + \
@@ -675,7 +674,6 @@ int netpoll_setup(struct netpoll *np)
 			goto release;
 		}
 
-		npinfo->rx_flags = 0;
 		npinfo->rx_np = NULL;
 
 		spin_lock_init(&npinfo->rx_lock);
@@ -757,7 +755,6 @@ int netpoll_setup(struct netpoll *np)
 
 	if (np->rx_hook) {
 		spin_lock_irqsave(&npinfo->rx_lock, flags);
-		npinfo->rx_flags |= NETPOLL_RX_ENABLED;
 		npinfo->rx_np = np;
 		spin_unlock_irqrestore(&npinfo->rx_lock, flags);
 	}
@@ -799,7 +796,6 @@ void netpoll_cleanup(struct netpoll *np)
 			if (npinfo->rx_np == np) {
 				spin_lock_irqsave(&npinfo->rx_lock, flags);
 				npinfo->rx_np = NULL;
-				npinfo->rx_flags &= ~NETPOLL_RX_ENABLED;
 				spin_unlock_irqrestore(&npinfo->rx_lock, flags);
 			}