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 <[email protected]> Signed-off-by: David S. Miller <[email protected]>
josf · Mar 4, 2022 · 7faef05 · 7faef05
1 parent 215b0f1
commit 7faef05
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Showing 3 changed files with 8 additions and 2 deletions.
diff --git 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
@@ -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
@@ -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 @@ static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
 	}
 	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;