From 7951e36ac620a9ba1bae0ac0ddd62d2e82285725 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 9 May 2024 09:35:01 -0600 Subject: net: pass back whether socket was empty post accept This adds an 'is_empty' argument to struct proto_accept_arg, which can be used to pass back information on whether or not the given socket has more connections to accept post the one just accepted. To utilize this information, the caller should initialize the 'is_empty' field to, eg, -1 and then check for 0/1 after the accept. If the field has been set, the caller knows whether there are more pending connections or not. If the field remains -1 after the accept call, the protocol doesn't support passing back this information. This patch wires it up for ipv4/6 TCP. Acked-by: Jakub Kicinski Signed-off-by: Jens Axboe --- include/net/sock.h | 1 + net/ipv4/inet_connection_sock.c | 1 + 2 files changed, 2 insertions(+) diff --git a/include/net/sock.h b/include/net/sock.h index 217079b3e3e8..5f4d0629348f 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -1197,6 +1197,7 @@ static inline void sk_prot_clear_nulls(struct sock *sk, int size) struct proto_accept_arg { int flags; int err; + int is_empty; bool kern; }; diff --git a/net/ipv4/inet_connection_sock.c b/net/ipv4/inet_connection_sock.c index 7734d189c66b..d81f74ce0f02 100644 --- a/net/ipv4/inet_connection_sock.c +++ b/net/ipv4/inet_connection_sock.c @@ -692,6 +692,7 @@ struct sock *inet_csk_accept(struct sock *sk, struct proto_accept_arg *arg) goto out_err; } req = reqsk_queue_remove(queue, sk); + arg->is_empty = reqsk_queue_empty(queue); newsk = req->sk; if (sk->sk_protocol == IPPROTO_TCP && -- cgit v1.2.3