[PATCH net-next] tcp: move tcp_v4_early_demux() to net/ipv4/ip_input.c

[PATCH net-next] tcp: move tcp_v4_early_demux() to net/ipv4/ip_input.c

[Eric Dumazet]

tcp_v4_early_demux() has a single caller : ip_rcv_finish_core().

Move it to net/ipv4/ip_input.c and mark it static, for possible
compiler/linker optimizations.

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/net/tcp.h   |  1 -
 net/ipv4/ip_input.c | 39 +++++++++++++++++++++++++++++++++++++++
 net/ipv4/tcp_ipv4.c | 38 --------------------------------------
 3 files changed, 39 insertions(+), 39 deletions(-)

diff --git a/include/net/tcp.h b/include/net/tcp.h
index a6464142380696e4948a836145ac7aca4ca3ec15..f07aef7faa65f8bfcdf93c9fe943f9b4d4a0dddb 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -363,7 +363,6 @@ int tcp_v4_err(struct sk_buff *skb, u32);
 
 void tcp_shutdown(struct sock *sk, int how);
 
-int tcp_v4_early_demux(struct sk_buff *skb);
 int tcp_v4_rcv(struct sk_buff *skb);
 
 void tcp_remove_empty_skb(struct sock *sk);
diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 19d3141dad1f8b031981aea40c311509583e9256..9860178752b8ccd70fd97d2a713b7c1a981fcc71 100644
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -319,6 +319,45 @@ static bool ip_can_use_hint(const struct sk_buff *skb, const struct iphdr *iph,
 	       ip_hdr(hint)->tos == iph->tos;
 }
 
+static int tcp_v4_early_demux(struct sk_buff *skb)
+{
+	struct net *net = dev_net_rcu(skb->dev);
+	const struct iphdr *iph;
+	const struct tcphdr *th;
+	struct sock *sk;
+
+	if (skb->pkt_type != PACKET_HOST)
+		return 0;
+
+	if (!pskb_may_pull(skb, skb_transport_offset(skb) +
+				sizeof(struct tcphdr)))
+		return 0;
+
+	iph = ip_hdr(skb);
+	th = tcp_hdr(skb);
+
+	if (th->doff < sizeof(struct tcphdr) / 4)
+		return 0;
+
+	sk = __inet_lookup_established(net, iph->saddr, th->source,
+				       iph->daddr, ntohs(th->dest),
+				       skb->skb_iif, inet_sdif(skb));
+	if (sk) {
+		skb->sk = sk;
+		skb->destructor = sock_edemux;
+		if (sk_fullsock(sk)) {
+			struct dst_entry *dst = rcu_dereference(sk->sk_rx_dst);
+
+			if (dst)
+				dst = dst_check(dst, 0);
+			if (dst &&
+			    sk->sk_rx_dst_ifindex == skb->skb_iif)
+				skb_dst_set_noref(skb, dst);
+		}
+	}
+	return 0;
+}
+
 static int ip_rcv_finish_core(struct net *net,
 			      struct sk_buff *skb, struct net_device *dev,
 			      const struct sk_buff *hint)
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 190e8a238876d966822531c74f17b896181e359f..f27995a6456198866ec2f9860b18d911e8dc1bcd 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1914,44 +1914,6 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
 }
 EXPORT_SYMBOL(tcp_v4_do_rcv);
 
-int tcp_v4_early_demux(struct sk_buff *skb)
-{
-	struct net *net = dev_net_rcu(skb->dev);
-	const struct iphdr *iph;
-	const struct tcphdr *th;
-	struct sock *sk;
-
-	if (skb->pkt_type != PACKET_HOST)
-		return 0;
-
-	if (!pskb_may_pull(skb, skb_transport_offset(skb) + sizeof(struct tcphdr)))
-		return 0;
-
-	iph = ip_hdr(skb);
-	th = tcp_hdr(skb);
-
-	if (th->doff < sizeof(struct tcphdr) / 4)
-		return 0;
-
-	sk = __inet_lookup_established(net, iph->saddr, th->source,
-				       iph->daddr, ntohs(th->dest),
-				       skb->skb_iif, inet_sdif(skb));
-	if (sk) {
-		skb->sk = sk;
-		skb->destructor = sock_edemux;
-		if (sk_fullsock(sk)) {
-			struct dst_entry *dst = rcu_dereference(sk->sk_rx_dst);
-
-			if (dst)
-				dst = dst_check(dst, 0);
-			if (dst &&
-			    sk->sk_rx_dst_ifindex == skb->skb_iif)
-				skb_dst_set_noref(skb, dst);
-		}
-	}
-	return 0;
-}
-
 bool tcp_add_backlog(struct sock *sk, struct sk_buff *skb,
 		     enum skb_drop_reason *reason)
 {
-- 
2.53.0.473.g4a7958ca14-goog

Re: [PATCH net-next] tcp: move tcp_v4_early_demux() to net/ipv4/ip_input.c

[David Ahern]

On 3/6/26 6:11 AM, Eric Dumazet wrote:
> tcp_v4_early_demux() has a single caller : ip_rcv_finish_core().
> 
> Move it to net/ipv4/ip_input.c and mark it static, for possible
> compiler/linker optimizations.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> ---
>  include/net/tcp.h   |  1 -
>  net/ipv4/ip_input.c | 39 +++++++++++++++++++++++++++++++++++++++
>  net/ipv4/tcp_ipv4.c | 38 --------------------------------------
>  3 files changed, 39 insertions(+), 39 deletions(-)
> 


Reviewed-by: David Ahern <dsahern@kernel.org>

Re: [PATCH net-next] tcp: move tcp_v4_early_demux() to net/ipv4/ip_input.c

[Kuniyuki Iwashima]

On Fri, Mar 6, 2026 at 5:11 AM Eric Dumazet <edumazet@google.com> wrote:
>
> tcp_v4_early_demux() has a single caller : ip_rcv_finish_core().
>
> Move it to net/ipv4/ip_input.c and mark it static, for possible
> compiler/linker optimizations.
>
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>

Re: [PATCH net-next] tcp: move tcp_v4_early_demux() to net/ipv4/ip_input.c

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Fri,  6 Mar 2026 13:11:30 +0000 you wrote:
> tcp_v4_early_demux() has a single caller : ip_rcv_finish_core().
> 
> Move it to net/ipv4/ip_input.c and mark it static, for possible
> compiler/linker optimizations.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> 
> [...]

Here is the summary with links:
  - [net-next] tcp: move tcp_v4_early_demux() to net/ipv4/ip_input.c
    https://git.kernel.org/netdev/net-next/c/50636e5ff886

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html