1 files changed, 28 insertions, 10 deletions

diff --git a/include/net/sch_generic.h b/include/net/sch_generic.h
index 3fe49d808957..f8c47429044a 100644
--- a/include/net/sch_generic.h
+++ b/include/net/sch_generic.h
@@ -53,7 +53,6 @@ struct Qdisc
         atomic_t                refcnt;
         unsigned long           state;
         struct sk_buff          *gso_skb;
-        struct sk_buff_head     requeue;
         struct sk_buff_head     q;
         struct netdev_queue     *dev_queue;
         struct Qdisc            *next_sched;
@@ -111,7 +110,7 @@ struct Qdisc_ops
 
         int                     (*enqueue)(struct sk_buff *, struct Qdisc *);
         struct sk_buff *        (*dequeue)(struct Qdisc *);
-        int                     (*requeue)(struct sk_buff *, struct Qdisc *);
+        struct sk_buff *        (*peek)(struct Qdisc *);
         unsigned int            (*drop)(struct Qdisc *);
 
         int                     (*init)(struct Qdisc *, struct nlattr *arg);
@@ -432,19 +431,38 @@ static inline struct sk_buff *qdisc_dequeue_tail(struct Qdisc *sch)
         return __qdisc_dequeue_tail(sch, &sch->q);
 }
 
-static inline int __qdisc_requeue(struct sk_buff *skb, struct Qdisc *sch,
-                                  struct sk_buff_head *list)
+static inline struct sk_buff *qdisc_peek_head(struct Qdisc *sch)
 {
-        __skb_queue_head(list, skb);
-        sch->qstats.backlog += qdisc_pkt_len(skb);
-        sch->qstats.requeues++;
+        return skb_peek(&sch->q);
+}
 
-        return NET_XMIT_SUCCESS;
+/* generic pseudo peek method for non-work-conserving qdisc */
+static inline struct sk_buff *qdisc_peek_dequeued(struct Qdisc *sch)
+{
+        /* we can reuse ->gso_skb because peek isn't called for root qdiscs */
+        if (!sch->gso_skb) {
+                sch->gso_skb = sch->dequeue(sch);
+                if (sch->gso_skb)
+                        /* it's still part of the queue */
+                        sch->q.qlen++;
+        }
+
+        return sch->gso_skb;
 }
 
-static inline int qdisc_requeue(struct sk_buff *skb, struct Qdisc *sch)
+/* use instead of qdisc->dequeue() for all qdiscs queried with ->peek() */
+static inline struct sk_buff *qdisc_dequeue_peeked(struct Qdisc *sch)
 {
-        return __qdisc_requeue(skb, sch, &sch->q);
+        struct sk_buff *skb = sch->gso_skb;
+
+        if (skb) {
+                sch->gso_skb = NULL;
+                sch->q.qlen--;
+        } else {
+                skb = sch->dequeue(sch);
+        }
+
+        return skb;
 }
 
 static inline void __qdisc_reset_queue(struct Qdisc *sch,