[PATCH net-next 1/7] net: dev: use kfree_skb_reason() for sch_handle_egress()

From: menglong8 . dong
Date: Thu Mar 03 2022 - 12:48:36 EST


From: Menglong Dong <imagedong@xxxxxxxxxxx>

Replace kfree_skb() used in sch_handle_egress() with kfree_skb_reason().
The drop reason SKB_DROP_REASON_QDISC_EGRESS is introduced. Considering
the code path of qdisc egerss, we make it distinct with the drop reason
of SKB_DROP_REASON_QDISC_DROP in the next commit.

Signed-off-by: Menglong Dong <imagedong@xxxxxxxxxxx>
---
include/linux/skbuff.h | 4 ++++
include/trace/events/skb.h | 1 +
net/core/dev.c | 2 +-
3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index d67941f78b92..ebd18850b63e 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -394,6 +394,10 @@ enum skb_drop_reason {
* entry is full
*/
SKB_DROP_REASON_NEIGH_DEAD, /* neigh entry is dead */
+ SKB_DROP_REASON_QDISC_EGRESS, /* qdisc of type egress check
+ * failed (mapbe an eBPF program
+ * is tricking?)
+ */
SKB_DROP_REASON_MAX,
};

diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h
index 1977f301260d..3cadf13448c6 100644
--- a/include/trace/events/skb.h
+++ b/include/trace/events/skb.h
@@ -45,6 +45,7 @@
EM(SKB_DROP_REASON_NEIGH_FAILED, NEIGH_FAILED) \
EM(SKB_DROP_REASON_NEIGH_QUEUEFULL, NEIGH_QUEUEFULL) \
EM(SKB_DROP_REASON_NEIGH_DEAD, NEIGH_DEAD) \
+ EM(SKB_DROP_REASON_QDISC_EGRESS, QDISC_EGRESS) \
EMe(SKB_DROP_REASON_MAX, MAX)

#undef EM
diff --git a/net/core/dev.c b/net/core/dev.c
index 2d6771075720..828946d74a19 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -3860,7 +3860,7 @@ sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
case TC_ACT_SHOT:
mini_qdisc_qstats_cpu_drop(miniq);
*ret = NET_XMIT_DROP;
- kfree_skb(skb);
+ kfree_skb_reason(skb, SKB_DROP_REASON_QDISC_EGRESS);
return NULL;
case TC_ACT_STOLEN:
case TC_ACT_QUEUED:
--
2.35.1