net: dev: add skb drop reasons to __dev_xmit_skb()

Add reasons for skb drops to __dev_xmit_skb() by replacing
kfree_skb_list() with kfree_skb_list_reason(). The drop reason of
SKB_DROP_REASON_QDISC_DROP is introduced for qdisc enqueue fails.

Signed-off-by: Menglong Dong <imagedong@tencent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 1f2de15..769d54b 100644 (file)
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -395,6 +395,10 @@ enum skb_drop_reason {
                                                 */
        SKB_DROP_REASON_NEIGH_DEAD,     /* neigh entry is dead */
        SKB_DROP_REASON_TC_EGRESS,      /* dropped in TC egress HOOK */
+       SKB_DROP_REASON_QDISC_DROP,     /* dropped by qdisc when packet
+                                        * outputting (failed to enqueue to
+                                        * current qdisc)
+                                        */
        SKB_DROP_REASON_MAX,
 };
 

diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h
index 53755e8..dbf3e2e 100644 (file)
--- a/include/trace/events/skb.h
+++ b/include/trace/events/skb.h
@@ -46,6 +46,7 @@
        EM(SKB_DROP_REASON_NEIGH_QUEUEFULL, NEIGH_QUEUEFULL)    \
        EM(SKB_DROP_REASON_NEIGH_DEAD, NEIGH_DEAD)              \
        EM(SKB_DROP_REASON_TC_EGRESS, TC_EGRESS)                \
+       EM(SKB_DROP_REASON_QDISC_DROP, QDISC_DROP)              \
        EMe(SKB_DROP_REASON_MAX, MAX)
 
 #undef EM

diff --git a/net/core/dev.c b/net/core/dev.c
index ef0b199..e2c1076 100644 (file)
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3759,7 +3759,8 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
 
 no_lock_out:
                if (unlikely(to_free))
-                       kfree_skb_list(to_free);
+                       kfree_skb_list_reason(to_free,
+                                             SKB_DROP_REASON_QDISC_DROP);
                return rc;
        }
 
@@ -3814,7 +3815,7 @@ no_lock_out:
        }
        spin_unlock(root_lock);
        if (unlikely(to_free))
-               kfree_skb_list(to_free);
+               kfree_skb_list_reason(to_free, SKB_DROP_REASON_QDISC_DROP);
        if (unlikely(contended))
                spin_unlock(&q->busylock);
        return rc;