From: Eric Dumazet <edumazet@google.com>
Date: Tue, 14 Oct 2025 17:19:03 +0000 (+0000)
Subject: net: add add indirect call wrapper in skb_release_head_state()
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=5b2b7dec05f3ab80d7bb7fa09acd43222fab6aa2;p=thirdparty%2Fkernel%2Flinux.git

net: add add indirect call wrapper in skb_release_head_state()

While stress testing UDP senders on a host with expensive indirect
calls, I found cpus processing TX completions where showing
a very high cost (20%) in sock_wfree() due to
CONFIG_MITIGATION_RETPOLINE=y.

Take care of TCP and UDP TX destructors and use INDIRECT_CALL_3() macro.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com>
Tested-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://patch.msgid.link/20251014171907.3554413-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 6be01454f262..8eb3c5820724 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -1136,7 +1136,16 @@ void skb_release_head_state(struct sk_buff *skb)
 	skb_dst_drop(skb);
 	if (skb->destructor) {
 		DEBUG_NET_WARN_ON_ONCE(in_hardirq());
-		skb->destructor(skb);
+#ifdef CONFIG_INET
+		INDIRECT_CALL_3(skb->destructor,
+				tcp_wfree, __sock_wfree, sock_wfree,
+				skb);
+#else
+		INDIRECT_CALL_1(skb->destructor,
+				sock_wfree,
+				skb);
+
+#endif
 	}
 #if IS_ENABLED(CONFIG_NF_CONNTRACK)
 	nf_conntrack_put(skb_nfct(skb));