sctp: deduplicate identical skb_checksum_ops (c3e933a5) · Commits · 戴 / test

The same skb_checksum_ops struct is defined twice in two different places, leading to code duplication. Declare it as a global variable into a common header instead of allocating it on the stack on each function call. bloat-o-meter reports a slight code shrink. add/remove: 1/1 grow/shrink: 0/10 up/down: 128/-1282 (-1154) Function old new delta sctp_csum_ops - 128 +128 crc32c_csum_ops 16 - -16 sctp_rcv 6616 6583 -33 sctp_packet_pack 4542 4504 -38 nf_conntrack_sctp_packet 4980 4926 -54 execute_masked_set_action 6453 6389 -64 tcf_csum_sctp 575 428 -147 sctp_gso_segment 1292 1126 -166 sctp_csum_check 579 412 -167 sctp_snat_handler 957 772 -185 sctp_dnat_handler 1321 1132 -189 l4proto_manip_pkt 2536 2313 -223 Total: Before=359297613, After=359296459, chg -0.00% Reviewed-by:

Xin Long <lucien.xin@gmail.com> Signed-off-by:

Matteo Croce <mcroce@redhat.com> Acked-by:

Neil Horman <nhorman@tuxdriver.com> Acked-by:

Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

include/net/sctp/checksum.h

+7 −5

Original line number	Diff line number	Diff line
		@@ -58,19 +58,21 @@ static inline __wsum sctp_csum_combine(__wsum csum, __wsum csum2,
		(__force __u32)csum2, len);
		}

		static const struct skb_checksum_ops sctp_csum_ops = {
		.update = sctp_csum_update,
		.combine = sctp_csum_combine,
		};

		static inline __le32 sctp_compute_cksum(const struct sk_buff *skb,
		unsigned int offset)
		{
		struct sctphdr sh = (struct sctphdr )(skb->data + offset);
		const struct skb_checksum_ops ops = {
		.update = sctp_csum_update,
		.combine = sctp_csum_combine,
		};
		__le32 old = sh->checksum;
		__wsum new;

		sh->checksum = 0;
		new = ~__skb_checksum(skb, offset, skb->len - offset, ~(__wsum)0, &ops);
		new = ~__skb_checksum(skb, offset, skb->len - offset, ~(__wsum)0,
		&sctp_csum_ops);
		sh->checksum = old;

		return cpu_to_le32((__force __u32)new);

net/sctp/offload.c

+1 −6

Original line number	Diff line number	Diff line
		@@ -103,11 +103,6 @@ static const struct net_offload sctp6_offload = {
		},
		};

		static const struct skb_checksum_ops crc32c_csum_ops = {
		.update = sctp_csum_update,
		.combine = sctp_csum_combine,
		};

		int __init sctp_offload_init(void)
		{
		int ret;
		@@ -120,7 +115,7 @@ int __init sctp_offload_init(void)
		if (ret)
		goto ipv4;

		crc32c_csum_stub = &crc32c_csum_ops;
		crc32c_csum_stub = &sctp_csum_ops;
		return ret;

		ipv4:

Admin message