net: Add and use skb_mark_not_on_list().

An SKB is not on a list if skb->next is NULL.

Codify this convention into a helper function and use it
where we are dequeueing an SKB and need to mark it as such.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 4 insertions, 4 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index ca78dc5a79a3..f76dd7e14dd6 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3231,7 +3231,7 @@ struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *de
         while (skb) {
                 struct sk_buff *next = skb->next;
 
-                skb->next = NULL;
+                skb_mark_not_on_list(skb);
                 rc = xmit_one(skb, dev, txq, next != NULL);
                 if (unlikely(!dev_xmit_complete(rc))) {
                         skb->next = next;
@@ -3331,7 +3331,7 @@ struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *d
 
         for (; skb != NULL; skb = next) {
                 next = skb->next;
-                skb->next = NULL;
+                skb_mark_not_on_list(skb);
 
                 /* in case skb wont be segmented, point to itself */
                 skb->prev = skb;
@@ -5296,7 +5296,7 @@ static void __napi_gro_flush_chain(struct napi_struct *napi, u32 index,
                 if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
                         return;
                 list_del(&skb->list);
-                skb->next = NULL;
+                skb_mark_not_on_list(skb);
                 napi_gro_complete(skb);
                 napi->gro_hash[index].count--;
         }
@@ -5482,7 +5482,7 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
 
         if (pp) {
                 list_del(&pp->list);
-                pp->next = NULL;
+                skb_mark_not_on_list(pp);
                 napi_gro_complete(pp);
                 napi->gro_hash[hash].count--;
         }