From bd5e5e1d41d316c47dd9001104b62033992daf6e Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Mon, 23 Feb 2026 10:07:27 +0000 Subject: tcp: inline __tcp_v4_send_check() Inline __tcp_v4_send_check(), like __tcp_v6_send_check(). Move tcp_v4_send_check() to tcp_output.c close to its fast path caller (__tcp_transmit_skb()). Note __tcp_v4_send_check() is still out-of-line for tcp4_gso_segment() because it is called in an unlikely() section. $ scripts/bloat-o-meter -t vmlinux.0 vmlinux.1 add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-9 (-9) Function old new delta __tcp_v4_send_check 130 121 -9 Total: Before=25143100, After=25143091, chg -0.00% Signed-off-by: Eric Dumazet Reviewed-by: Kuniyuki Iwashima Link: https://patch.msgid.link/20260223100729.3761597-2-edumazet@google.com Signed-off-by: Jakub Kicinski --- include/net/tcp.h | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/net/tcp.h b/include/net/tcp.h index 40e72b9cb85f..3c84433f3d57 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -2382,7 +2382,15 @@ void tcp_gro_complete(struct sk_buff *skb); static inline void tcp_gro_complete(struct sk_buff *skb) { } #endif -void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, __be32 daddr); +static inline void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, + __be32 daddr) +{ + struct tcphdr *th = tcp_hdr(skb); + + th->check = ~tcp_v4_check(skb->len, saddr, daddr, 0); + skb->csum_start = skb_transport_header(skb) - skb->head; + skb->csum_offset = offsetof(struct tcphdr, check); +} static inline u32 tcp_notsent_lowat(const struct tcp_sock *tp) { -- cgit v1.2.3