From 31f1fbcb346c9342f6860c322b3f33b2acbc640b Mon Sep 17 00:00:00 2001 From: Peilin Ye Date: Thu, 22 Sep 2022 21:59:13 -0700 Subject: udp: Refactor udp_read_skb() Delete the unnecessary while loop in udp_read_skb() for readability. Additionally, since recv_actor() cannot return a value greater than skb->len (see sk_psock_verdict_recv()), remove the redundant check. Suggested-by: Cong Wang Signed-off-by: Peilin Ye Link: https://lore.kernel.org/r/343b5d8090a3eb764068e9f1d392939e2b423747.1663909008.git.peilin.ye@bytedance.com Signed-off-by: Jakub Kicinski --- net/ipv4/udp.c | 46 +++++++++++++++++----------------------------- 1 file changed, 17 insertions(+), 29 deletions(-) (limited to 'net/ipv4') diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c index 560d9eadeaa5..d63118ce5900 100644 --- a/net/ipv4/udp.c +++ b/net/ipv4/udp.c @@ -1801,41 +1801,29 @@ EXPORT_SYMBOL(__skb_recv_udp); int udp_read_skb(struct sock *sk, skb_read_actor_t recv_actor) { - int copied = 0; - - while (1) { - struct sk_buff *skb; - int err, used; - - skb = skb_recv_udp(sk, MSG_DONTWAIT, &err); - if (!skb) - return err; + struct sk_buff *skb; + int err, copied; - if (udp_lib_checksum_complete(skb)) { - __UDP_INC_STATS(sock_net(sk), UDP_MIB_CSUMERRORS, - IS_UDPLITE(sk)); - __UDP_INC_STATS(sock_net(sk), UDP_MIB_INERRORS, - IS_UDPLITE(sk)); - atomic_inc(&sk->sk_drops); - kfree_skb(skb); - continue; - } +try_again: + skb = skb_recv_udp(sk, MSG_DONTWAIT, &err); + if (!skb) + return err; - WARN_ON_ONCE(!skb_set_owner_sk_safe(skb, sk)); - used = recv_actor(sk, skb); - if (used <= 0) { - if (!copied) - copied = used; - kfree_skb(skb); - break; - } else if (used <= skb->len) { - copied += used; - } + if (udp_lib_checksum_complete(skb)) { + int is_udplite = IS_UDPLITE(sk); + struct net *net = sock_net(sk); + __UDP_INC_STATS(net, UDP_MIB_CSUMERRORS, is_udplite); + __UDP_INC_STATS(net, UDP_MIB_INERRORS, is_udplite); + atomic_inc(&sk->sk_drops); kfree_skb(skb); - break; + goto try_again; } + WARN_ON_ONCE(!skb_set_owner_sk_safe(skb, sk)); + copied = recv_actor(sk, skb); + kfree_skb(skb); + return copied; } EXPORT_SYMBOL(udp_read_skb); -- cgit v1.2.3