Commit 31f1fbcb authored by Peilin Ye's avatar Peilin Ye Committed by Jakub Kicinski
Browse files

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: default avatarCong Wang <cong.wang@bytedance.com>
Signed-off-by: default avatarPeilin Ye <peilin.ye@bytedance.com>
Link: https://lore.kernel.org/r/343b5d8090a3eb764068e9f1d392939e2b423747.1663909008.git.peilin.ye@bytedance.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent c52add61

net/ipv4/udp.c

+17 −29
Original line number Diff line number Diff line
@@ -1801,40 +1801,28 @@ 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;

	int err, copied;



try_again:

	skb = skb_recv_udp(sk, MSG_DONTWAIT, &err);

	if (!skb)

		return err;



	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));

		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);

			continue;

		goto try_again;

	}



	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;

		}



	copied = recv_actor(sk, skb);

	kfree_skb(skb);

		break;

	}



	return copied;

}