[PATCH net-next v3 09/12] net: vxlan: add drop reasons support to vxlan_xmit_one()

From: Menglong Dong
Date: Mon Sep 09 2024 - 03:26:36 EST


Replace kfree_skb/dev_kfree_skb with kfree_skb_reason in vxlan_xmit_one.
No drop reasons are introduced in this commit.

The only concern of mine is replacing dev_kfree_skb with
kfree_skb_reason. The dev_kfree_skb is equal to consume_skb, and I'm not
sure if we can change it to kfree_skb here. In my option, the skb is
"dropped" here, isn't it?

Signed-off-by: Menglong Dong <dongml2@xxxxxxxxxxxxxxx>
---
drivers/net/vxlan/vxlan_core.c | 19 ++++++++++++++-----
1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/drivers/net/vxlan/vxlan_core.c b/drivers/net/vxlan/vxlan_core.c
index 6f35448fbf3c..78e4a78a94f0 100644
--- a/drivers/net/vxlan/vxlan_core.c
+++ b/drivers/net/vxlan/vxlan_core.c
@@ -2374,13 +2374,16 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
bool use_cache;
bool udp_sum = false;
bool xnet = !net_eq(vxlan->net, dev_net(vxlan->dev));
+ enum skb_drop_reason reason;
bool no_eth_encap;
__be32 vni = 0;

no_eth_encap = flags & VXLAN_F_GPE && skb->protocol != htons(ETH_P_TEB);
- if (!skb_vlan_inet_prepare(skb, no_eth_encap))
+ reason = skb_vlan_inet_prepare_reason(skb, no_eth_encap);
+ if (reason)
goto drop;

+ reason = SKB_DROP_REASON_NOT_SPECIFIED;
old_iph = ip_hdr(skb);

info = skb_tunnel_info(skb);
@@ -2484,6 +2487,7 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
tos, use_cache ? dst_cache : NULL);
if (IS_ERR(rt)) {
err = PTR_ERR(rt);
+ reason = SKB_DROP_REASON_IP_OUTNOROUTES;
goto tx_error;
}

@@ -2535,8 +2539,10 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);
err = vxlan_build_skb(skb, ndst, sizeof(struct iphdr),
vni, md, flags, udp_sum);
- if (err < 0)
+ if (err < 0) {
+ reason = SKB_DROP_REASON_NOMEM;
goto tx_error;
+ }

udp_tunnel_xmit_skb(rt, sock4->sock->sk, skb, saddr,
pkey->u.ipv4.dst, tos, ttl, df,
@@ -2556,6 +2562,7 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
if (IS_ERR(ndst)) {
err = PTR_ERR(ndst);
ndst = NULL;
+ reason = SKB_DROP_REASON_IP_OUTNOROUTES;
goto tx_error;
}

@@ -2596,8 +2603,10 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
skb_scrub_packet(skb, xnet);
err = vxlan_build_skb(skb, ndst, sizeof(struct ipv6hdr),
vni, md, flags, udp_sum);
- if (err < 0)
+ if (err < 0) {
+ reason = SKB_DROP_REASON_NOMEM;
goto tx_error;
+ }

udp_tunnel6_xmit_skb(ndst, sock6->sock->sk, skb, dev,
&saddr, &pkey->u.ipv6.dst, tos, ttl,
@@ -2612,7 +2621,7 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
drop:
dev_core_stats_tx_dropped_inc(dev);
vxlan_vnifilter_count(vxlan, vni, NULL, VXLAN_VNI_STATS_TX_DROPS, 0);
- dev_kfree_skb(skb);
+ kfree_skb_reason(skb, reason);
return;

tx_error:
@@ -2624,7 +2633,7 @@ void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev,
dst_release(ndst);
DEV_STATS_INC(dev, tx_errors);
vxlan_vnifilter_count(vxlan, vni, NULL, VXLAN_VNI_STATS_TX_ERRORS, 0);
- kfree_skb(skb);
+ kfree_skb_reason(skb, reason);
}

static void vxlan_xmit_nh(struct sk_buff *skb, struct net_device *dev,
--
2.39.2