提交 058dc334 编写于 作者: I Ilpo Järvinen 提交者: David S. Miller

[TCP]: reduce tcp_output's indentation levels a bit

Signed-off-by: NIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
上级 4828e7f4
......@@ -1673,75 +1673,77 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int m
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *next_skb = tcp_write_queue_next(sk, skb);
int skb_size, next_skb_size;
u16 flags;
/* The first test we must make is that neither of these two
* SKB's are still referenced by someone else.
*/
if (!skb_cloned(skb) && !skb_cloned(next_skb)) {
int skb_size = skb->len, next_skb_size = next_skb->len;
u16 flags = TCP_SKB_CB(skb)->flags;
if (skb_cloned(skb) || skb_cloned(next_skb))
return;
/* Also punt if next skb has been SACK'd. */
if (TCP_SKB_CB(next_skb)->sacked & TCPCB_SACKED_ACKED)
return;
skb_size = skb->len;
next_skb_size = next_skb->len;
flags = TCP_SKB_CB(skb)->flags;
/* Next skb is out of window. */
if (after(TCP_SKB_CB(next_skb)->end_seq, tcp_wnd_end(tp)))
return;
/* Also punt if next skb has been SACK'd. */
if (TCP_SKB_CB(next_skb)->sacked & TCPCB_SACKED_ACKED)
return;
/* Punt if not enough space exists in the first SKB for
* the data in the second, or the total combined payload
* would exceed the MSS.
*/
if ((next_skb_size > skb_tailroom(skb)) ||
((skb_size + next_skb_size) > mss_now))
return;
/* Next skb is out of window. */
if (after(TCP_SKB_CB(next_skb)->end_seq, tcp_wnd_end(tp)))
return;
BUG_ON(tcp_skb_pcount(skb) != 1 ||
tcp_skb_pcount(next_skb) != 1);
/* Punt if not enough space exists in the first SKB for
* the data in the second, or the total combined payload
* would exceed the MSS.
*/
if ((next_skb_size > skb_tailroom(skb)) ||
((skb_size + next_skb_size) > mss_now))
return;
tcp_highest_sack_combine(sk, next_skb, skb);
BUG_ON(tcp_skb_pcount(skb) != 1 || tcp_skb_pcount(next_skb) != 1);
/* Ok. We will be able to collapse the packet. */
tcp_unlink_write_queue(next_skb, sk);
tcp_highest_sack_combine(sk, next_skb, skb);
skb_copy_from_linear_data(next_skb,
skb_put(skb, next_skb_size),
next_skb_size);
/* Ok. We will be able to collapse the packet. */
tcp_unlink_write_queue(next_skb, sk);
if (next_skb->ip_summed == CHECKSUM_PARTIAL)
skb->ip_summed = CHECKSUM_PARTIAL;
skb_copy_from_linear_data(next_skb, skb_put(skb, next_skb_size),
next_skb_size);
if (skb->ip_summed != CHECKSUM_PARTIAL)
skb->csum = csum_block_add(skb->csum, next_skb->csum, skb_size);
if (next_skb->ip_summed == CHECKSUM_PARTIAL)
skb->ip_summed = CHECKSUM_PARTIAL;
/* Update sequence range on original skb. */
TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(next_skb)->end_seq;
if (skb->ip_summed != CHECKSUM_PARTIAL)
skb->csum = csum_block_add(skb->csum, next_skb->csum, skb_size);
/* Merge over control information. */
flags |= TCP_SKB_CB(next_skb)->flags; /* This moves PSH/FIN etc. over */
TCP_SKB_CB(skb)->flags = flags;
/* Update sequence range on original skb. */
TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(next_skb)->end_seq;
/* All done, get rid of second SKB and account for it so
* packet counting does not break.
*/
TCP_SKB_CB(skb)->sacked |= TCP_SKB_CB(next_skb)->sacked & TCPCB_EVER_RETRANS;
if (TCP_SKB_CB(next_skb)->sacked&TCPCB_SACKED_RETRANS)
tp->retrans_out -= tcp_skb_pcount(next_skb);
if (TCP_SKB_CB(next_skb)->sacked&TCPCB_LOST)
tp->lost_out -= tcp_skb_pcount(next_skb);
/* Reno case is special. Sigh... */
if (tcp_is_reno(tp) && tp->sacked_out)
tcp_dec_pcount_approx(&tp->sacked_out, next_skb);
tcp_adjust_fackets_out(sk, next_skb, tcp_skb_pcount(next_skb));
tp->packets_out -= tcp_skb_pcount(next_skb);
/* changed transmit queue under us so clear hints */
tcp_clear_retrans_hints_partial(tp);
sk_wmem_free_skb(sk, next_skb);
}
/* Merge over control information. */
flags |= TCP_SKB_CB(next_skb)->flags; /* This moves PSH/FIN etc. over */
TCP_SKB_CB(skb)->flags = flags;
/* All done, get rid of second SKB and account for it so
* packet counting does not break.
*/
TCP_SKB_CB(skb)->sacked |= TCP_SKB_CB(next_skb)->sacked & TCPCB_EVER_RETRANS;
if (TCP_SKB_CB(next_skb)->sacked & TCPCB_SACKED_RETRANS)
tp->retrans_out -= tcp_skb_pcount(next_skb);
if (TCP_SKB_CB(next_skb)->sacked & TCPCB_LOST)
tp->lost_out -= tcp_skb_pcount(next_skb);
/* Reno case is special. Sigh... */
if (tcp_is_reno(tp) && tp->sacked_out)
tcp_dec_pcount_approx(&tp->sacked_out, next_skb);
tcp_adjust_fackets_out(sk, next_skb, tcp_skb_pcount(next_skb));
tp->packets_out -= tcp_skb_pcount(next_skb);
/* changed transmit queue under us so clear hints */
tcp_clear_retrans_hints_partial(tp);
sk_wmem_free_skb(sk, next_skb);
}
/* Do a simple retransmit without using the backoff mechanisms in
......@@ -2416,37 +2418,38 @@ void tcp_send_delayed_ack(struct sock *sk)
/* This routine sends an ack and also updates the window. */
void tcp_send_ack(struct sock *sk)
{
/* If we have been reset, we may not send again. */
if (sk->sk_state != TCP_CLOSE) {
struct sk_buff *buff;
struct sk_buff *buff;
/* We are not putting this on the write queue, so
* tcp_transmit_skb() will set the ownership to this
* sock.
*/
buff = alloc_skb(MAX_TCP_HEADER, GFP_ATOMIC);
if (buff == NULL) {
inet_csk_schedule_ack(sk);
inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN;
inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
TCP_DELACK_MAX, TCP_RTO_MAX);
return;
}
/* If we have been reset, we may not send again. */
if (sk->sk_state == TCP_CLOSE)
return;
/* Reserve space for headers and prepare control bits. */
skb_reserve(buff, MAX_TCP_HEADER);
buff->csum = 0;
TCP_SKB_CB(buff)->flags = TCPCB_FLAG_ACK;
TCP_SKB_CB(buff)->sacked = 0;
skb_shinfo(buff)->gso_segs = 1;
skb_shinfo(buff)->gso_size = 0;
skb_shinfo(buff)->gso_type = 0;
/* Send it off, this clears delayed acks for us. */
TCP_SKB_CB(buff)->seq = TCP_SKB_CB(buff)->end_seq = tcp_acceptable_seq(sk);
TCP_SKB_CB(buff)->when = tcp_time_stamp;
tcp_transmit_skb(sk, buff, 0, GFP_ATOMIC);
/* We are not putting this on the write queue, so
* tcp_transmit_skb() will set the ownership to this
* sock.
*/
buff = alloc_skb(MAX_TCP_HEADER, GFP_ATOMIC);
if (buff == NULL) {
inet_csk_schedule_ack(sk);
inet_csk(sk)->icsk_ack.ato = TCP_ATO_MIN;
inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,
TCP_DELACK_MAX, TCP_RTO_MAX);
return;
}
/* Reserve space for headers and prepare control bits. */
skb_reserve(buff, MAX_TCP_HEADER);
buff->csum = 0;
TCP_SKB_CB(buff)->flags = TCPCB_FLAG_ACK;
TCP_SKB_CB(buff)->sacked = 0;
skb_shinfo(buff)->gso_segs = 1;
skb_shinfo(buff)->gso_size = 0;
skb_shinfo(buff)->gso_type = 0;
/* Send it off, this clears delayed acks for us. */
TCP_SKB_CB(buff)->seq = TCP_SKB_CB(buff)->end_seq = tcp_acceptable_seq(sk);
TCP_SKB_CB(buff)->when = tcp_time_stamp;
tcp_transmit_skb(sk, buff, 0, GFP_ATOMIC);
}
/* This routine sends a packet with an out of date sequence
......@@ -2491,46 +2494,46 @@ static int tcp_xmit_probe_skb(struct sock *sk, int urgent)
int tcp_write_wakeup(struct sock *sk)
{
if (sk->sk_state != TCP_CLOSE) {
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
if ((skb = tcp_send_head(sk)) != NULL &&
before(TCP_SKB_CB(skb)->seq, tcp_wnd_end(tp))) {
int err;
unsigned int mss = tcp_current_mss(sk, 0);
unsigned int seg_size = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq;
if (before(tp->pushed_seq, TCP_SKB_CB(skb)->end_seq))
tp->pushed_seq = TCP_SKB_CB(skb)->end_seq;
/* We are probing the opening of a window
* but the window size is != 0
* must have been a result SWS avoidance ( sender )
*/
if (seg_size < TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq ||
skb->len > mss) {
seg_size = min(seg_size, mss);
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
if (tcp_fragment(sk, skb, seg_size, mss))
return -1;
} else if (!tcp_skb_pcount(skb))
tcp_set_skb_tso_segs(sk, skb, mss);
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
if (sk->sk_state == TCP_CLOSE)
return -1;
if ((skb = tcp_send_head(sk)) != NULL &&
before(TCP_SKB_CB(skb)->seq, tcp_wnd_end(tp))) {
int err;
unsigned int mss = tcp_current_mss(sk, 0);
unsigned int seg_size = tcp_wnd_end(tp) - TCP_SKB_CB(skb)->seq;
if (before(tp->pushed_seq, TCP_SKB_CB(skb)->end_seq))
tp->pushed_seq = TCP_SKB_CB(skb)->end_seq;
/* We are probing the opening of a window
* but the window size is != 0
* must have been a result SWS avoidance ( sender )
*/
if (seg_size < TCP_SKB_CB(skb)->end_seq - TCP_SKB_CB(skb)->seq ||
skb->len > mss) {
seg_size = min(seg_size, mss);
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
TCP_SKB_CB(skb)->when = tcp_time_stamp;
err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC);
if (!err)
tcp_event_new_data_sent(sk, skb);
return err;
} else {
if (tp->urg_mode &&
between(tp->snd_up, tp->snd_una+1, tp->snd_una+0xFFFF))
tcp_xmit_probe_skb(sk, 1);
return tcp_xmit_probe_skb(sk, 0);
}
if (tcp_fragment(sk, skb, seg_size, mss))
return -1;
} else if (!tcp_skb_pcount(skb))
tcp_set_skb_tso_segs(sk, skb, mss);
TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_PSH;
TCP_SKB_CB(skb)->when = tcp_time_stamp;
err = tcp_transmit_skb(sk, skb, 1, GFP_ATOMIC);
if (!err)
tcp_event_new_data_sent(sk, skb);
return err;
} else {
if (tp->urg_mode &&
between(tp->snd_up, tp->snd_una + 1, tp->snd_una + 0xFFFF))
tcp_xmit_probe_skb(sk, 1);
return tcp_xmit_probe_skb(sk, 0);
}
return -1;
}
/* A window probe timeout has occurred. If window is not closed send
......
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