mirror of https://gitee.com/openkylin/linux.git
[TCP]: reduce tcp_output's indentation levels a bit
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ilpo Järvinen
David S. Miller
parent
4828e7f49a
commit
058dc3342b
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@ -1673,75 +1673,77 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int m
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{
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struct tcp_sock *tp = tcp_sk(sk);
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struct sk_buff *next_skb = tcp_write_queue_next(sk, skb);
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int skb_size, next_skb_size;
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u16 flags;
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/* The first test we must make is that neither of these two
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* SKB's are still referenced by someone else.
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*/
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if (!skb_cloned(skb) && !skb_cloned(next_skb)) {
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int skb_size = skb->len, next_skb_size = next_skb->len;
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u16 flags = TCP_SKB_CB(skb)->flags;
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if (skb_cloned(skb) || skb_cloned(next_skb))
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return;
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/* Also punt if next skb has been SACK'd. */
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if (TCP_SKB_CB(next_skb)->sacked & TCPCB_SACKED_ACKED)
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return;
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skb_size = skb->len;
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next_skb_size = next_skb->len;
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flags = TCP_SKB_CB(skb)->flags;
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/* Next skb is out of window. */
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if (after(TCP_SKB_CB(next_skb)->end_seq, tcp_wnd_end(tp)))
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return;
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/* Also punt if next skb has been SACK'd. */
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if (TCP_SKB_CB(next_skb)->sacked & TCPCB_SACKED_ACKED)
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return;
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/* Punt if not enough space exists in the first SKB for
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* the data in the second, or the total combined payload
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* would exceed the MSS.
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*/
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if ((next_skb_size > skb_tailroom(skb)) ||
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((skb_size + next_skb_size) > mss_now))
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return;
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/* Next skb is out of window. */
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if (after(TCP_SKB_CB(next_skb)->end_seq, tcp_wnd_end(tp)))
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return;
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BUG_ON(tcp_skb_pcount(skb) != 1 ||
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tcp_skb_pcount(next_skb) != 1);
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/* Punt if not enough space exists in the first SKB for
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* the data in the second, or the total combined payload
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* would exceed the MSS.
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*/
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if ((next_skb_size > skb_tailroom(skb)) ||
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((skb_size + next_skb_size) > mss_now))
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return;
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tcp_highest_sack_combine(sk, next_skb, skb);
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BUG_ON(tcp_skb_pcount(skb) != 1 || tcp_skb_pcount(next_skb) != 1);
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/* Ok. We will be able to collapse the packet. */
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tcp_unlink_write_queue(next_skb, sk);
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tcp_highest_sack_combine(sk, next_skb, skb);
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skb_copy_from_linear_data(next_skb,
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skb_put(skb, next_skb_size),
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next_skb_size);
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/* Ok. We will be able to collapse the packet. */
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tcp_unlink_write_queue(next_skb, sk);
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if (next_skb->ip_summed == CHECKSUM_PARTIAL)
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skb->ip_summed = CHECKSUM_PARTIAL;
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skb_copy_from_linear_data(next_skb, skb_put(skb, next_skb_size),
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next_skb_size);
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if (skb->ip_summed != CHECKSUM_PARTIAL)
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skb->csum = csum_block_add(skb->csum, next_skb->csum, skb_size);
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if (next_skb->ip_summed == CHECKSUM_PARTIAL)
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skb->ip_summed = CHECKSUM_PARTIAL;
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/* Update sequence range on original skb. */
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TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(next_skb)->end_seq;
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if (skb->ip_summed != CHECKSUM_PARTIAL)
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skb->csum = csum_block_add(skb->csum, next_skb->csum, skb_size);
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/* Merge over control information. */
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flags |= TCP_SKB_CB(next_skb)->flags; /* This moves PSH/FIN etc. over */
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TCP_SKB_CB(skb)->flags = flags;
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/* Update sequence range on original skb. */
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TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(next_skb)->end_seq;
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/* All done, get rid of second SKB and account for it so
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* packet counting does not break.
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*/
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TCP_SKB_CB(skb)->sacked |= TCP_SKB_CB(next_skb)->sacked & TCPCB_EVER_RETRANS;
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if (TCP_SKB_CB(next_skb)->sacked&TCPCB_SACKED_RETRANS)
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tp->retrans_out -= tcp_skb_pcount(next_skb);
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if (TCP_SKB_CB(next_skb)->sacked&TCPCB_LOST)
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tp->lost_out -= tcp_skb_pcount(next_skb);
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/* Reno case is special. Sigh... */
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if (tcp_is_reno(tp) && tp->sacked_out)
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tcp_dec_pcount_approx(&tp->sacked_out, next_skb);
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/* Merge over control information. */
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flags |= TCP_SKB_CB(next_skb)->flags; /* This moves PSH/FIN etc. over */
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TCP_SKB_CB(skb)->flags = flags;
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tcp_adjust_fackets_out(sk, next_skb, tcp_skb_pcount(next_skb));
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tp->packets_out -= tcp_skb_pcount(next_skb);
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/* All done, get rid of second SKB and account for it so
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* packet counting does not break.
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*/
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TCP_SKB_CB(skb)->sacked |= TCP_SKB_CB(next_skb)->sacked & TCPCB_EVER_RETRANS;
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if (TCP_SKB_CB(next_skb)->sacked & TCPCB_SACKED_RETRANS)
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tp->retrans_out -= tcp_skb_pcount(next_skb);
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if (TCP_SKB_CB(next_skb)->sacked & TCPCB_LOST)
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tp->lost_out -= tcp_skb_pcount(next_skb);
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/* Reno case is special. Sigh... */
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if (tcp_is_reno(tp) && tp->sacked_out)
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tcp_dec_pcount_approx(&tp->sacked_out, next_skb);
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/* changed transmit queue under us so clear hints */
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tcp_clear_retrans_hints_partial(tp);
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tcp_adjust_fackets_out(sk, next_skb, tcp_skb_pcount(next_skb));
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tp->packets_out -= tcp_skb_pcount(next_skb);
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sk_wmem_free_skb(sk, next_skb);
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}
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/* changed transmit queue under us so clear hints */
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tcp_clear_retrans_hints_partial(tp);
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sk_wmem_free_skb(sk, next_skb);
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}
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/* Do a simple retransmit without using the backoff mechanisms in
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@ -2416,37 +2418,38 @@ void tcp_send_delayed_ack(struct sock *sk)
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/* This routine sends an ack and also updates the window. */
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void tcp_send_ack(struct sock *sk)
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{
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struct sk_buff *buff;
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/* If we have been reset, we may not send again. */
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if (sk->sk_state != TCP_CLOSE) {
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struct sk_buff *buff;
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if (sk->sk_state == TCP_CLOSE)
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return;
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/* We are not putting this on the write queue, so
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* tcp_transmit_skb() will set the ownership to this
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* sock.
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*/
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buff = alloc_skb(MAX_TCP_HEADER, GFP_ATOMIC);
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if (buff == NULL) {
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inet_csk_schedule_ack(sk);
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inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN;
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inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
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TCP_DELACK_MAX, TCP_RTO_MAX);
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return;
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}
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/* Reserve space for headers and prepare control bits. */
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skb_reserve(buff, MAX_TCP_HEADER);
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buff->csum = 0;
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TCP_SKB_CB(buff)->flags = TCPCB_FLAG_ACK;
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TCP_SKB_CB(buff)->sacked = 0;
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skb_shinfo(buff)->gso_segs = 1;
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skb_shinfo(buff)->gso_size = 0;
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skb_shinfo(buff)->gso_type = 0;
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/* Send it off, this clears delayed acks for us. */
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TCP_SKB_CB(buff)->seq = TCP_SKB_CB(buff)->end_seq = tcp_acceptable_seq(sk);
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TCP_SKB_CB(buff)->when = tcp_time_stamp;
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tcp_transmit_skb(sk, buff, 0, GFP_ATOMIC);
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/* We are not putting this on the write queue, so
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* tcp_transmit_skb() will set the ownership to this
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* sock.
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*/
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buff = alloc_skb(MAX_TCP_HEADER, GFP_ATOMIC);
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if (buff == NULL) {
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inet_csk_schedule_ack(sk);
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inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN;
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inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
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TCP_DELACK_MAX, TCP_RTO_MAX);
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return;
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}
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/* Reserve space for headers and prepare control bits. */
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skb_reserve(buff, MAX_TCP_HEADER);
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buff->csum = 0;
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TCP_SKB_CB(buff)->flags = TCPCB_FLAG_ACK;
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TCP_SKB_CB(buff)->sacked = 0;
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skb_shinfo(buff)->gso_segs = 1;
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skb_shinfo(buff)->gso_size = 0;
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skb_shinfo(buff)->gso_type = 0;
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/* Send it off, this clears delayed acks for us. */
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TCP_SKB_CB(buff)->seq = TCP_SKB_CB(buff)->end_seq = tcp_acceptable_seq(sk);
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TCP_SKB_CB(buff)->when = tcp_time_stamp;
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tcp_transmit_skb(sk, buff, 0, GFP_ATOMIC);
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}
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/* This routine sends a packet with an out of date sequence
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@ -2491,46 +2494,46 @@ static int tcp_xmit_probe_skb(struct sock *sk, int urgent)
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int tcp_write_wakeup(struct sock *sk)
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{
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if (sk->sk_state != TCP_CLOSE) {
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struct tcp_sock *tp = tcp_sk(sk);
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struct sk_buff *skb;
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struct tcp_sock *tp = tcp_sk(sk);
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struct sk_buff *skb;
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if ((skb = tcp_send_head(sk)) != NULL &&
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before(TCP_SKB_CB(skb)->seq, tcp_wnd_end(tp))) {
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int err;
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unsigned int mss = tcp_current_mss(sk, 0);
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unsigned int seg_size = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq;
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if (sk->sk_state == TCP_CLOSE)
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return -1;
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if (before(tp->pushed_seq, TCP_SKB_CB(skb)->end_seq))
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tp->pushed_seq = TCP_SKB_CB(skb)->end_seq;
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if ((skb = tcp_send_head(sk)) != NULL &&
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before(TCP_SKB_CB(skb)->seq, tcp_wnd_end(tp))) {
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int err;
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unsigned int mss = tcp_current_mss(sk, 0);
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unsigned int seg_size = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq;
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/* We are probing the opening of a window
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* but the window size is != 0
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* must have been a result SWS avoidance ( sender )
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*/
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if (seg_size < TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq ||
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skb->len > mss) {
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seg_size = min(seg_size, mss);
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TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
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if (tcp_fragment(sk, skb, seg_size, mss))
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return -1;
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} else if (!tcp_skb_pcount(skb))
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tcp_set_skb_tso_segs(sk, skb, mss);
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if (before(tp->pushed_seq, TCP_SKB_CB(skb)->end_seq))
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tp->pushed_seq = TCP_SKB_CB(skb)->end_seq;
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/* We are probing the opening of a window
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* but the window size is != 0
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* must have been a result SWS avoidance ( sender )
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*/
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if (seg_size < TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq ||
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skb->len > mss) {
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seg_size = min(seg_size, mss);
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TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
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TCP_SKB_CB(skb)->when = tcp_time_stamp;
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err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC);
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if (!err)
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tcp_event_new_data_sent(sk, skb);
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return err;
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} else {
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if (tp->urg_mode &&
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between(tp->snd_up, tp->snd_una+1, tp->snd_una+0xFFFF))
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tcp_xmit_probe_skb(sk, 1);
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return tcp_xmit_probe_skb(sk, 0);
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}
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if (tcp_fragment(sk, skb, seg_size, mss))
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return -1;
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} else if (!tcp_skb_pcount(skb))
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tcp_set_skb_tso_segs(sk, skb, mss);
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TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
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TCP_SKB_CB(skb)->when = tcp_time_stamp;
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err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC);
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if (!err)
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tcp_event_new_data_sent(sk, skb);
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return err;
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} else {
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if (tp->urg_mode &&
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between(tp->snd_up, tp->snd_una + 1, tp->snd_una + 0xFFFF))
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tcp_xmit_probe_skb(sk, 1);
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return tcp_xmit_probe_skb(sk, 0);
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}
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return -1;
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}
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/* A window probe timeout has occurred. If window is not closed send
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