Commit 701b9519 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'tcp-tx-side-cleanups' 



Eric Dumazet says:

====================
tcp: tx side cleanups

We no longer need to set skb->reserved_tailroom because
TCP sendmsg() do not put payload in skb->head anymore.

Also do some cleanups around skb->ip_summed/csum,
and CP_SKB_CB(skb)->sacked for fresh skbs.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 911e3a46 8b7d8c2b

include/net/tcp.h

+1 −1
Original line number Diff line number Diff line
@@ -311,7 +311,7 @@ void tcp_shutdown(struct sock *sk, int how); 
int tcp_v4_early_demux(struct sk_buff *skb);

int tcp_v4_rcv(struct sk_buff *skb);



void tcp_remove_empty_skb(struct sock *sk, struct sk_buff *skb);

void tcp_remove_empty_skb(struct sock *sk);

int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw);

int tcp_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);

int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size);

net/ipv4/tcp.c

+7 −22
Original line number Diff line number Diff line
@@ -658,10 +658,8 @@ void tcp_skb_entail(struct sock *sk, struct sk_buff *skb) 
	struct tcp_sock *tp = tcp_sk(sk);

	struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);



	skb->csum    = 0;

	tcb->seq     = tcb->end_seq = tp->write_seq;

	tcb->tcp_flags = TCPHDR_ACK;

	tcb->sacked  = 0;

	__skb_header_release(skb);

	tcp_add_write_queue_tail(sk, skb);

	sk_wmem_queued_add(sk, skb->truesize);
@@ -876,11 +874,7 @@ struct sk_buff *tcp_stream_alloc_skb(struct sock *sk, int size, gfp_t gfp, 
		}

		if (likely(mem_scheduled)) {

			skb_reserve(skb, MAX_TCP_HEADER);

			/*

			 * Make sure that we have exactly size bytes

			 * available to the caller, no more, no less.

			 */

			skb->reserved_tailroom = skb->end - skb->tail - size;

			skb->ip_summed = CHECKSUM_PARTIAL;

			INIT_LIST_HEAD(&skb->tcp_tsorted_anchor);

			return skb;

		}
@@ -933,8 +927,10 @@ int tcp_send_mss(struct sock *sk, int *size_goal, int flags) 
 * importantly be able to generate EPOLLOUT for Edge Trigger epoll()

 * users.

 */

void tcp_remove_empty_skb(struct sock *sk, struct sk_buff *skb)

void tcp_remove_empty_skb(struct sock *sk)

{

	struct sk_buff *skb = tcp_write_queue_tail(sk);



	if (skb && TCP_SKB_CB(skb)->seq == TCP_SKB_CB(skb)->end_seq) {

		tcp_unlink_write_queue(skb, sk);

		if (tcp_write_queue_empty(sk))
@@ -996,7 +992,6 @@ static struct sk_buff *tcp_build_frag(struct sock *sk, int size_goal, int flags, 
	skb->truesize += copy;

	sk_wmem_queued_add(sk, copy);

	sk_mem_charge(sk, copy);

	skb->ip_summed = CHECKSUM_PARTIAL;

	WRITE_ONCE(tp->write_seq, tp->write_seq + copy);

	TCP_SKB_CB(skb)->end_seq += copy;

	tcp_skb_pcount_set(skb, 0);
@@ -1087,7 +1082,7 @@ ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset, 
	return copied;



do_error:

	tcp_remove_empty_skb(sk, tcp_write_queue_tail(sk));

	tcp_remove_empty_skb(sk);

	if (copied)

		goto out;

out_err:
@@ -1292,7 +1287,6 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) 
				goto wait_for_space;



			process_backlog++;

			skb->ip_summed = CHECKSUM_PARTIAL;



			tcp_skb_entail(sk, skb);

			copy = size_goal;
@@ -1309,14 +1303,7 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) 
		if (copy > msg_data_left(msg))

			copy = msg_data_left(msg);



		/* Where to copy to? */

		if (skb_availroom(skb) > 0 && !zc) {

			/* We have some space in skb head. Superb! */

			copy = min_t(int, copy, skb_availroom(skb));

			err = skb_add_data_nocache(sk, skb, &msg->msg_iter, copy);

			if (err)

				goto do_fault;

		} else if (!zc) {

		if (!zc) {

			bool merge = true;

			int i = skb_shinfo(skb)->nr_frags;

			struct page_frag *pfrag = sk_page_frag(sk);
@@ -1415,9 +1402,7 @@ int tcp_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) 
	return copied + copied_syn;



do_error:

	skb = tcp_write_queue_tail(sk);

do_fault:

	tcp_remove_empty_skb(sk, skb);

	tcp_remove_empty_skb(sk);



	if (copied + copied_syn)

		goto out;

net/ipv4/tcp_output.c

+3 −19
Original line number Diff line number Diff line
@@ -394,7 +394,6 @@ static void tcp_init_nondata_skb(struct sk_buff *skb, u32 seq, u8 flags) 
	skb->ip_summed = CHECKSUM_PARTIAL;



	TCP_SKB_CB(skb)->tcp_flags = flags;

	TCP_SKB_CB(skb)->sacked = 0;



	tcp_skb_pcount_set(skb, 1);
@@ -1590,8 +1589,6 @@ int tcp_fragment(struct sock *sk, enum tcp_queue tcp_queue, 


	skb_split(skb, buff, len);



	buff->ip_summed = CHECKSUM_PARTIAL;



	buff->tstamp = skb->tstamp;

	tcp_fragment_tstamp(skb, buff);
@@ -1676,7 +1673,6 @@ int tcp_trim_head(struct sock *sk, struct sk_buff *skb, u32 len) 
	delta_truesize = __pskb_trim_head(skb, len);



	TCP_SKB_CB(skb)->seq += len;

	skb->ip_summed = CHECKSUM_PARTIAL;



	if (delta_truesize) {

		skb->truesize	   -= delta_truesize;
@@ -2142,12 +2138,8 @@ static int tso_fragment(struct sock *sk, struct sk_buff *skb, unsigned int len, 
	TCP_SKB_CB(skb)->tcp_flags = flags & ~(TCPHDR_FIN | TCPHDR_PSH);

	TCP_SKB_CB(buff)->tcp_flags = flags;



	/* This packet was never sent out yet, so no SACK bits. */

	TCP_SKB_CB(buff)->sacked = 0;



	tcp_skb_fragment_eor(skb, buff);



	buff->ip_summed = CHECKSUM_PARTIAL;

	skb_split(skb, buff, len);

	tcp_fragment_tstamp(skb, buff);
@@ -2401,9 +2393,6 @@ static int tcp_mtu_probe(struct sock *sk) 
	TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(skb)->seq;

	TCP_SKB_CB(nskb)->end_seq = TCP_SKB_CB(skb)->seq + probe_size;

	TCP_SKB_CB(nskb)->tcp_flags = TCPHDR_ACK;

	TCP_SKB_CB(nskb)->sacked = 0;

	nskb->csum = 0;

	nskb->ip_summed = CHECKSUM_PARTIAL;



	tcp_insert_write_queue_before(nskb, skb, sk);

	tcp_highest_sack_replace(sk, skb, nskb);
@@ -3045,13 +3034,9 @@ static bool tcp_collapse_retrans(struct sock *sk, struct sk_buff *skb) 


	BUG_ON(tcp_skb_pcount(skb) != 1 || tcp_skb_pcount(next_skb) != 1);



	if (next_skb_size) {

		if (next_skb_size <= skb_availroom(skb))

			skb_copy_bits(next_skb, 0, skb_put(skb, next_skb_size),

				      next_skb_size);

		else if (!tcp_skb_shift(skb, next_skb, 1, next_skb_size))

	if (next_skb_size && !tcp_skb_shift(skb, next_skb, 1, next_skb_size))

		return false;

	}



	tcp_highest_sack_replace(sk, next_skb, skb);



	/* Update sequence range on original skb. */
@@ -3757,7 +3742,6 @@ static int tcp_send_syn_data(struct sock *sk, struct sk_buff *syn) 
	syn_data = tcp_stream_alloc_skb(sk, space, sk->sk_allocation, false);

	if (!syn_data)

		goto fallback;

	syn_data->ip_summed = CHECKSUM_PARTIAL;

	memcpy(syn_data->cb, syn->cb, sizeof(syn->cb));

	if (space) {

		int copied = copy_from_iter(skb_put(syn_data, space), space,

net/ipv6/tcp_ipv6.c

+0 −1
Original line number Diff line number Diff line
@@ -969,7 +969,6 @@ static void tcp_v6_send_response(const struct sock *sk, struct sk_buff *skb, u32 
	fl6.flowlabel = label;



	buff->ip_summed = CHECKSUM_PARTIAL;

	buff->csum = 0;



	__tcp_v6_send_check(buff, &fl6.saddr, &fl6.daddr);

net/mptcp/protocol.c

+3 −4
Original line number Diff line number Diff line
@@ -1174,7 +1174,7 @@ static struct sk_buff *__mptcp_do_alloc_tx_skb(struct sock *sk, gfp_t gfp) 
	if (likely(skb)) {

		if (likely(__mptcp_add_ext(skb, gfp))) {

			skb_reserve(skb, MAX_TCP_HEADER);

			skb->reserved_tailroom = skb->end - skb->tail;

			skb->ip_summed = CHECKSUM_PARTIAL;

			INIT_LIST_HEAD(&skb->tcp_tsorted_anchor);

			return skb;

		}
@@ -1291,7 +1291,7 @@ static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, 
		u64 snd_una = READ_ONCE(msk->snd_una);



		if (snd_una != msk->snd_nxt) {

			tcp_remove_empty_skb(ssk, tcp_write_queue_tail(ssk));

			tcp_remove_empty_skb(ssk);

			return 0;

		}
@@ -1307,7 +1307,7 @@ static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, 


	copy = min_t(size_t, copy, info->limit - info->sent);

	if (!sk_wmem_schedule(ssk, copy)) {

		tcp_remove_empty_skb(ssk, tcp_write_queue_tail(ssk));

		tcp_remove_empty_skb(ssk);

		return -ENOMEM;

	}
@@ -1323,7 +1323,6 @@ static int mptcp_sendmsg_frag(struct sock *sk, struct sock *ssk, 
	skb->truesize += copy;

	sk_wmem_queued_add(ssk, copy);

	sk_mem_charge(ssk, copy);

	skb->ip_summed = CHECKSUM_PARTIAL;

	WRITE_ONCE(tcp_sk(ssk)->write_seq, tcp_sk(ssk)->write_seq + copy);

	TCP_SKB_CB(skb)->end_seq += copy;

	tcp_skb_pcount_set(skb, 0);