[PATCH net-next v2 2/4] net: use indirect call helpers for dst_output

From: Brian Vazquez
Date: Fri Dec 11 2020 - 18:35:36 EST


From: brianvv <brianvv@xxxxxxxxxx>

This patch avoids the indirect call for the common case:
ip6_output and ip_output

Signed-off-by: brianvv <brianvv@xxxxxxxxxx>
---
include/net/dst.h | 8 +++++++-
net/ipv4/ip_output.c | 1 +
net/ipv6/ip6_output.c | 1 +
3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/include/net/dst.h b/include/net/dst.h
index 98cf6e8c06c4..3932e9931f08 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -436,10 +436,16 @@ static inline void dst_set_expires(struct dst_entry *dst, int timeout)
dst->expires = expires;
}

+INDIRECT_CALLABLE_DECLARE(int ip6_output(struct net *, struct sock *,
+ struct sk_buff *));
+INDIRECT_CALLABLE_DECLARE(int ip_output(struct net *, struct sock *,
+ struct sk_buff *));
/* Output packet to network from transport. */
static inline int dst_output(struct net *net, struct sock *sk, struct sk_buff *skb)
{
- return skb_dst(skb)->output(net, sk, skb);
+ return INDIRECT_CALL_INET(skb_dst(skb)->output,
+ ip6_output, ip_output,
+ net, sk, skb);
}

INDIRECT_CALLABLE_DECLARE(int ip6_input(struct sk_buff *));
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 879b76ae4435..356c89575b08 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -434,6 +434,7 @@ int ip_output(struct net *net, struct sock *sk, struct sk_buff *skb)
ip_finish_output,
!(IPCB(skb)->flags & IPSKB_REROUTED));
}
+EXPORT_SYMBOL(ip_output);

/*
* copy saddr and daddr, possibly using 64bit load/stores
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 749ad72386b2..1260c0cac592 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -178,6 +178,7 @@ int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
ip6_finish_output,
!(IP6CB(skb)->flags & IP6SKB_REROUTED));
}
+EXPORT_SYMBOL(ip6_output);

bool ip6_autoflowlabel(struct net *net, const struct ipv6_pinfo *np)
{
--
2.29.2.576.ga3fc446d84-goog