[PATCH v2 net-next 3/3] gro: inline tcp6_gro_complete()

[Eric Dumazet <edumazet@google.com>]

Remove one function call from GRO stack for native IPv6 + TCP packets.

$ scripts/bloat-o-meter -t vmlinux.2 vmlinux.3
add/remove: 0/0 grow/shrink: 1/1 up/down: 298/-5 (293)
Function                                     old     new   delta
ipv6_gro_complete                            435     733    +298
tcp6_gro_complete                            311     306      -5
Total: Before=22593532, After=22593825, chg +0.00%

Signed-off-by: Eric Dumazet <edumazet@google.com>
---
 include/net/gro.h        |  2 +-
 include/net/tcp.h        |  1 -
 net/ipv6/ip6_offload.c   | 21 +++++++++------------
 net/ipv6/tcpv6_offload.c |  2 +-
 4 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/include/net/gro.h b/include/net/gro.h
index 85e5eeed4c90feef9440c57af9382b0e9ead1219..2300b6da05b2728ec40f42228f8fa9c195d8479c 100644
--- a/include/net/gro.h
+++ b/include/net/gro.h
@@ -406,7 +406,7 @@ INDIRECT_CALLABLE_DECLARE(struct sk_buff *udp4_gro_receive(struct list_head *,
 INDIRECT_CALLABLE_DECLARE(int udp4_gro_complete(struct sk_buff *, int));
 
 struct sk_buff *udp6_gro_receive(struct list_head *, struct sk_buff *);
-INDIRECT_CALLABLE_DECLARE(int udp6_gro_complete(struct sk_buff *, int));
+int udp6_gro_complete(struct sk_buff *, int);
 
 #define indirect_call_gro_receive_inet(cb, f2, f1, head, skb)	\
 ({								\
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 3b94c84888a884d9ca8eb602ad1f7d4f941f3ef9..ebdf59d435b8002ca9b90803f40720a58ce3e809 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -2326,7 +2326,6 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb,
 				struct tcphdr *th);
 INDIRECT_CALLABLE_DECLARE(int tcp4_gro_complete(struct sk_buff *skb, int thoff));
 INDIRECT_CALLABLE_DECLARE(struct sk_buff *tcp4_gro_receive(struct list_head *head, struct sk_buff *skb));
-INDIRECT_CALLABLE_DECLARE(int tcp6_gro_complete(struct sk_buff *skb, int thoff));
 #ifdef CONFIG_INET
 void tcp_gro_complete(struct sk_buff *skb);
 #else
diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c
index 4d96154c0dcd019322908ab6ddaa663a2a565e44..32a104ead8760d33e152e0b0a6a6896d70d155b5 100644
--- a/net/ipv6/ip6_offload.c
+++ b/net/ipv6/ip6_offload.c
@@ -21,16 +21,6 @@
 #include "ip6_offload.h"
 #include "tcpv6_offload.c"
 
-/* All GRO functions are always builtin, except UDP over ipv6, which lays in
- * ipv6 module, as it depends on UDPv6 lookup function, so we need special care
- * when ipv6 is built as a module
- */
-#if IS_BUILTIN(CONFIG_IPV6)
-#define INDIRECT_CALL_L4(f, f2, f1, ...) INDIRECT_CALL_2(f, f2, f1, __VA_ARGS__)
-#else
-#define INDIRECT_CALL_L4(f, f2, f1, ...) INDIRECT_CALL_1(f, f2, __VA_ARGS__)
-#endif
-
 static int ipv6_gro_pull_exthdrs(struct sk_buff *skb, int off, int proto)
 {
 	const struct net_offload *ops = NULL;
@@ -383,11 +373,18 @@ INDIRECT_CALLABLE_SCOPE int ipv6_gro_complete(struct sk_buff *skb, int nhoff)
 	}
 
 	nhoff += sizeof(*iph) + ipv6_exthdrs_len(iph, &ops);
+
+	if (likely(ops == &net_hotdata.tcpv6_offload))
+		return tcp6_gro_complete(skb, nhoff);
+#if IS_BUILTIN(CONFIG_IPV6)
+	if (ops == &net_hotdata.udpv6_offload)
+		return udp6_gro_complete(skb, nhoff);
+#endif
+
 	if (WARN_ON(!ops || !ops->callbacks.gro_complete))
 		goto out;
 
-	err = INDIRECT_CALL_L4(ops->callbacks.gro_complete, tcp6_gro_complete,
-			       udp6_gro_complete, skb, nhoff);
+	err = ops->callbacks.gro_complete(skb, nhoff);
 
 out:
 	return err;
diff --git a/net/ipv6/tcpv6_offload.c b/net/ipv6/tcpv6_offload.c
index 7f19ce423058870f285b7f8ae2a4d116d783f9fb..46fa2069d321663ed232e2836db77e3fcb1f4f07 100644
--- a/net/ipv6/tcpv6_offload.c
+++ b/net/ipv6/tcpv6_offload.c
@@ -67,7 +67,7 @@ static __always_inline struct sk_buff *tcp6_gro_receive(struct list_head *head,
 	return NULL;
 }
 
-INDIRECT_CALLABLE_SCOPE int tcp6_gro_complete(struct sk_buff *skb, int thoff)
+static __always_inline int tcp6_gro_complete(struct sk_buff *skb, int thoff)
 {
 	const u16 offset = NAPI_GRO_CB(skb)->network_offsets[skb->encapsulation];
 	const struct ipv6hdr *iph = (struct ipv6hdr *)(skb->data + offset);
-- 
2.52.0.457.g6b5491de43-goog