From: Rafał Miłecki <ra...@milecki.pl>
Netfilter allows disabling checksum verification of incoming packets by
setting nf_conntrack_checksum variable. That feature is very useful for
home routers which:
1. Most of the time just /forward/ network traffic
2. Have slow CPU(s) and csum calculation is a challenge
Some projects like OpenWrt set nf_conntrack_checksum to 0 by default.
It would be nice to allow similar optimization in the GRO code paths.
This patch simply reuses nf_conntrack_checksum variable to skip
skb_gro_checksum_validate() calls if applicable.
Signed-off-by: Rafał Miłecki <ra...@milecki.pl>
---
Hi guys,
I'm not very familiar with net subsystem, please let me know if there is
a better way of implementing such a feature.
---
net/ipv4/tcp_offload.c | 3 +++
net/ipv6/tcpv6_offload.c | 3 +++
2 files changed, 6 insertions(+)
diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c
index 30abde86db45..734a3c0f3d4a 100644
--- a/net/ipv4/tcp_offload.c
+++ b/net/ipv4/tcp_offload.c
@@ -311,6 +311,9 @@ struct sk_buff *tcp4_gro_receive(struct list_head *head,
struct sk_buff *skb)
{
/* Don't bother verifying checksum if we're going to flush anyway. */
if (!NAPI_GRO_CB(skb)->flush &&
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
+ dev_net(skb->dev)->ct.sysctl_checksum &&
+#endif
skb_gro_checksum_validate(skb, IPPROTO_TCP,
inet_gro_compute_pseudo)) {
NAPI_GRO_CB(skb)->flush = 1;
diff --git a/net/ipv6/tcpv6_offload.c b/net/ipv6/tcpv6_offload.c
index 39db5a226855..2144afa56fa3 100644
--- a/net/ipv6/tcpv6_offload.c
+++ b/net/ipv6/tcpv6_offload.c
@@ -18,6 +18,9 @@ struct sk_buff *tcp6_gro_receive(struct list_head *head,
struct sk_buff *skb)
{
/* Don't bother verifying checksum if we're going to flush anyway. */
if (!NAPI_GRO_CB(skb)->flush &&
+#if IS_ENABLED(CONFIG_NF_CONNTRACK)
+ dev_net(skb->dev)->ct.sysctl_checksum &&
+#endif
skb_gro_checksum_validate(skb, IPPROTO_TCP,
ip6_gro_compute_pseudo)) {
NAPI_GRO_CB(skb)->flush = 1;
--
2.34.1
_______________________________________________
openwrt-devel mailing list
openwrt-devel@lists.openwrt.org
https://lists.openwrt.org/mailman/listinfo/openwrt-devel
