From: Eric Dumazet edumazet@google.com
mainline inclusion from mainline-v5.17-rc1 commit 3df684c1a3d08a4f649689053a3d527b3b5fda9e category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I65HYE
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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TCP uses sk_eat_skb() when skbs can be removed from receive queue. However, the call to skb_orphan() from __kfree_skb() incurs an indirect call so sock_rfee(), which is more expensive than a direct call, especially for CONFIG_RETPOLINE=y.
Add tcp_eat_recv_skb() function to make the call before __kfree_skb().
Signed-off-by: Eric Dumazet edumazet@google.com Signed-off-by: David S. Miller davem@davemloft.net (cherry picked from commit 3df684c1a3d08a4f649689053a3d527b3b5fda9e) Signed-off-by: Liu Jian liujian56@huawei.com --- net/ipv4/tcp.c | 20 +++++++++++++++----- 1 file changed, 15 insertions(+), 5 deletions(-)
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 81693b83a8515..e1cc494b5c78e 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -1596,6 +1596,16 @@ void tcp_cleanup_rbuf(struct sock *sk, int copied) tcp_send_ack(sk); }
+static void tcp_eat_recv_skb(struct sock *sk, struct sk_buff *skb) +{ + if (likely(skb->destructor == sock_rfree)) { + sock_rfree(skb); + skb->destructor = NULL; + skb->sk = NULL; + } + sk_eat_skb(sk, skb); +} + static struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off) { struct sk_buff *skb; @@ -1615,7 +1625,7 @@ static struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off) * splitted a fat GRO packet, while we released socket lock * in skb_splice_bits() */ - sk_eat_skb(sk, skb); + tcp_eat_recv_skb(sk, skb); } return NULL; } @@ -1683,11 +1693,11 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, continue; } if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) { - sk_eat_skb(sk, skb); + tcp_eat_recv_skb(sk, skb); ++seq; break; } - sk_eat_skb(sk, skb); + tcp_eat_recv_skb(sk, skb); if (!desc->count) break; WRITE_ONCE(tp->copied_seq, seq); @@ -2317,14 +2327,14 @@ int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock, if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) goto found_fin_ok; if (!(flags & MSG_PEEK)) - sk_eat_skb(sk, skb); + tcp_eat_recv_skb(sk, skb); continue;
found_fin_ok: /* Process the FIN. */ WRITE_ONCE(*seq, *seq + 1); if (!(flags & MSG_PEEK)) - sk_eat_skb(sk, skb); + tcp_eat_recv_skb(sk, skb); break; } while (len > 0);