net: create tcp_gro_lookup helper function

This pulls the flow port matching out of tcp_gro_receive, so that it can be
reused for the next change, which adds the TCP fraglist GRO heuristic.

Acked-by: Paolo Abeni <pabeni@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Reviewed-by: David Ahern <dsahern@kernel.org>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/include/net/tcp.h b/include/net/tcp.h
index 0a51e6a45bce9b9b7c5e458c23e1a337b20a1f26..79c4e8947b5d2f64662b2290e1866a1748866c6c 100644 (file)
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -2191,6 +2191,7 @@ void tcp_v4_destroy_sock(struct sock *sk);
 
 struct sk_buff *tcp_gso_segment(struct sk_buff *skb,
                                netdev_features_t features);
+struct sk_buff *tcp_gro_lookup(struct list_head *head, struct tcphdr *th);
 struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb);
 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));

diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c
index aa75086763156a85f0f34d549e9fe987c1e0a3fe..4a194a9d36cda974bf3af5a1ff260c854ef4cc81 100644 (file)
--- a/net/ipv4/tcp_offload.c
+++ b/net/ipv4/tcp_offload.c
@@ -245,6 +245,27 @@ out:
        return segs;
 }
 
+struct sk_buff *tcp_gro_lookup(struct list_head *head, struct tcphdr *th)
+{
+       struct tcphdr *th2;
+       struct sk_buff *p;
+
+       list_for_each_entry(p, head, list) {
+               if (!NAPI_GRO_CB(p)->same_flow)
+                       continue;
+
+               th2 = tcp_hdr(p);
+               if (*(u32 *)&th->source ^ *(u32 *)&th2->source) {
+                       NAPI_GRO_CB(p)->same_flow = 0;
+                       continue;
+               }
+
+               return p;
+       }
+
+       return NULL;
+}
+
 struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb)
 {
        struct sk_buff *pp = NULL;
@@ -282,24 +303,12 @@ struct sk_buff *tcp_gro_receive(struct list_head *head, struct sk_buff *skb)
        len = skb_gro_len(skb);
        flags = tcp_flag_word(th);
 
-       list_for_each_entry(p, head, list) {
-               if (!NAPI_GRO_CB(p)->same_flow)
-                       continue;
-
-               th2 = tcp_hdr(p);
-
-               if (*(u32 *)&th->source ^ *(u32 *)&th2->source) {
-                       NAPI_GRO_CB(p)->same_flow = 0;
-                       continue;
-               }
-
-               goto found;
-       }
-       p = NULL;
-       goto out_check_final;
+       p = tcp_gro_lookup(head, th);
+       if (!p)
+               goto out_check_final;
 
-found:
        /* Include the IP ID check below from the inner most IP hdr */
+       th2 = tcp_hdr(p);
        flush = NAPI_GRO_CB(p)->flush;
        flush |= (__force int)(flags & TCP_FLAG_CWR);
        flush |= (__force int)((flags ^ tcp_flag_word(th2)) &