From a5736edda10ca2ba075606baad1dda3f2426766d Mon Sep 17 00:00:00 2001
From: Menglong Dong <imagedong@tencent.com>
Date: Sat, 26 Feb 2022 12:18:30 +0800
Subject: [PATCH] net: neigh: use kfree_skb_reason() for __neigh_event_send()
Replace kfree_skb() used in __neigh_event_send() with
kfree_skb_reason(). Following drop reasons are added:
SKB_DROP_REASON_NEIGH_FAILED
SKB_DROP_REASON_NEIGH_QUEUEFULL
SKB_DROP_REASON_NEIGH_DEAD
The first two reasons above should be the hot path that skb drops
in neighbour subsystem.
Reviewed-by: Mengen Sun <mengensun@tencent.com>
Reviewed-by: Hao Peng <flyingpeng@tencent.com>
Signed-off-by: Menglong Dong <imagedong@tencent.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
include/linux/skbuff.h | 5 +++++
include/trace/events/skb.h | 3 +++
net/core/neighbour.c | 6 +++---
3 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 62b4bed1b7bc..d67941f78b92 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -389,6 +389,11 @@ enum skb_drop_reason {
SKB_DROP_REASON_NEIGH_CREATEFAIL, /* failed to create neigh
* entry
*/
+ SKB_DROP_REASON_NEIGH_FAILED, /* neigh entry in failed state */
+ SKB_DROP_REASON_NEIGH_QUEUEFULL, /* arp_queue for neigh
+ * entry is full
+ */
+ SKB_DROP_REASON_NEIGH_DEAD, /* neigh entry is dead */
SKB_DROP_REASON_MAX,
};
diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h
index 97f8097651da..1977f301260d 100644
--- a/include/trace/events/skb.h
+++ b/include/trace/events/skb.h
@@ -42,6 +42,9 @@
BPF_CGROUP_EGRESS) \
EM(SKB_DROP_REASON_IPV6DISABLED, IPV6DISABLED) \
EM(SKB_DROP_REASON_NEIGH_CREATEFAIL, NEIGH_CREATEFAIL) \
+ EM(SKB_DROP_REASON_NEIGH_FAILED, NEIGH_FAILED) \
+ EM(SKB_DROP_REASON_NEIGH_QUEUEFULL, NEIGH_QUEUEFULL) \
+ EM(SKB_DROP_REASON_NEIGH_DEAD, NEIGH_DEAD) \
EMe(SKB_DROP_REASON_MAX, MAX)
#undef EM
diff --git a/net/core/neighbour.c b/net/core/neighbour.c
index ec0bf737b076..f64ebd050f6c 100644
--- a/net/core/neighbour.c
+++ b/net/core/neighbour.c
@@ -1171,7 +1171,7 @@ int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb,
neigh->updated = jiffies;
write_unlock_bh(&neigh->lock);
- kfree_skb(skb);
+ kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_FAILED);
return 1;
}
} else if (neigh->nud_state & NUD_STALE) {
@@ -1193,7 +1193,7 @@ int __neigh_event_send(struct neighbour *neigh, struct sk_buff *skb,
if (!buff)
break;
neigh->arp_queue_len_bytes -= buff->truesize;
- kfree_skb(buff);
+ kfree_skb_reason(buff, SKB_DROP_REASON_NEIGH_QUEUEFULL);
NEIGH_CACHE_STAT_INC(neigh->tbl, unres_discards);
}
skb_dst_force(skb);
@@ -1215,7 +1215,7 @@ out_dead:
if (neigh->nud_state & NUD_STALE)
goto out_unlock_bh;
write_unlock_bh(&neigh->lock);
- kfree_skb(skb);
+ kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_DEAD);
trace_neigh_event_send_dead(neigh, 1);
return 1;
}