diff options
| author | Eric Dumazet <edumazet@google.com> | 2025-03-20 15:16:04 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-03-25 17:37:16 +0300 |
| commit | 0de2a5c4b824da2205658ebebb99a55c43cdf60f (patch) | |
| tree | 35c86479d8dd4f78f78c63164a17f70fc9e72b3a /include | |
| parent | c1dacb45778ca9749cb2a5dd61c2d196979ecfce (diff) | |
| download | linux-0de2a5c4b824da2205658ebebb99a55c43cdf60f.tar.xz | |
tcp: avoid atomic operations on sk->sk_rmem_alloc
TCP uses generic skb_set_owner_r() and sock_rfree()
for received packets, with socket lock being owned.
Switch to private versions, avoiding two atomic operations
per packet.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250320121604.3342831-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/net/tcp.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h index 4450c384ef17..df04dc09c519 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -779,6 +779,7 @@ static inline int tcp_bound_to_half_wnd(struct tcp_sock *tp, int pktsize) /* tcp.c */ void tcp_get_info(struct sock *, struct tcp_info *); +void tcp_sock_rfree(struct sk_buff *skb); /* Read 'sendfile()'-style from a TCP socket */ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, @@ -2898,4 +2899,18 @@ enum skb_drop_reason tcp_inbound_hash(struct sock *sk, const void *saddr, const void *daddr, int family, int dif, int sdif); +/* version of skb_set_owner_r() avoiding one atomic_add() */ +static inline void tcp_skb_set_owner_r(struct sk_buff *skb, struct sock *sk) +{ + skb_orphan(skb); + skb->sk = sk; + skb->destructor = tcp_sock_rfree; + + sock_owned_by_me(sk); + atomic_set(&sk->sk_rmem_alloc, + atomic_read(&sk->sk_rmem_alloc) + skb->truesize); + + sk_forward_alloc_add(sk, -skb->truesize); +} + #endif /* _TCP_H */ |