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[52.52.7.82]) by smtp.gmail.com with ESMTPSA id g26-20020ac842da000000b0035bb4805309sm1191561qtm.42.2022.09.14.01.15.34 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 14 Sep 2022 01:15:36 -0700 (PDT) From: Peilin Ye To: Eric Dumazet , "David S. Miller" , Hideaki YOSHIFUJI , David Ahern , Jakub Kicinski , Paolo Abeni Cc: Peilin Ye , Cong Wang , Kuniyuki Iwashima , Alexei Starovoitov , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Peilin Ye Subject: [PATCH net-next 1/2] udp: Refactor udp_read_skb() Date: Wed, 14 Sep 2022 01:15:30 -0700 Message-Id: <03db9765fe1ef0f61bfc87fc68b5a95b4126aa4e.1663143016.git.peilin.ye@bytedance.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Peilin Ye 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 --- Depends on: "[PATCH net v2] net: Use WARN_ON_ONCE() in {tcp,udp}_read_skb()" https://lore.kernel.org/all/20220913184016.16095-1-yepeilin.cs@gmail.com/ Thanks, Peilin Ye net/ipv4/udp.c | 46 +++++++++++++++++----------------------------- 1 file changed, 17 insertions(+), 29 deletions(-) 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);