diff options
| author | Feng Yang <yangfeng@kylinos.cn> | 2025-07-08 13:40:53 +0800 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2025-07-09 19:25:57 -0700 |
| commit | 76d727ae02b527426c73a446b9291df376db8944 (patch) | |
| tree | afb7f6ca02242b253841d75b1f1cff070937ebaa | |
| parent | fb6045762901d37b28b90a01228c25dbb99bcc7c (diff) | |
skbuff: Add MSG_MORE flag to optimize tcp large packet transmission
When using sockmap for forwarding, the average latency for different packet sizes
after sending 10,000 packets is as follows:
size old(us) new(us)
512 56 55
1472 58 58
1600 106 81
3000 145 105
5000 182 125
Suggested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Feng Yang <yangfeng@kylinos.cn>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250708054053.39551-1-yangfeng59949@163.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/core/skbuff.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index a6efabff2173..ee0274417948 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -3230,6 +3230,7 @@ typedef int (*sendmsg_func)(struct sock *sk, struct msghdr *msg); static int __skb_send_sock(struct sock *sk, struct sk_buff *skb, int offset, int len, sendmsg_func sendmsg, int flags) { + int more_hint = sk_is_tcp(sk) ? MSG_MORE : 0; unsigned int orig_len = len; struct sk_buff *head = skb; unsigned short fragidx; @@ -3247,6 +3248,8 @@ do_frag_list: kv.iov_len = slen; memset(&msg, 0, sizeof(msg)); msg.msg_flags = MSG_DONTWAIT | flags; + if (slen < len) + msg.msg_flags |= more_hint; iov_iter_kvec(&msg.msg_iter, ITER_SOURCE, &kv, 1, slen); ret = INDIRECT_CALL_2(sendmsg, sendmsg_locked, @@ -3287,6 +3290,8 @@ do_frag_list: flags, }; + if (slen < len) + msg.msg_flags |= more_hint; bvec_set_page(&bvec, skb_frag_page(frag), slen, skb_frag_off(frag) + offset); iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, |