[TCP]: Abstract out all write queue operations.
This allows the write queue implementation to be changed,
for example, to one which allows fast interval searching.
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index d0a3630..22d0bb0 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1044,7 +1044,7 @@
cached_skb = tp->fastpath_skb_hint;
cached_fack_count = tp->fastpath_cnt_hint;
if (!cached_skb) {
- cached_skb = sk->sk_write_queue.next;
+ cached_skb = tcp_write_queue_head(sk);
cached_fack_count = 0;
}
@@ -1061,10 +1061,13 @@
if (after(end_seq, tp->high_seq))
flag |= FLAG_DATA_LOST;
- sk_stream_for_retrans_queue_from(skb, sk) {
+ tcp_for_write_queue_from(skb, sk) {
int in_sack, pcount;
u8 sacked;
+ if (skb == tcp_send_head(sk))
+ break;
+
cached_skb = skb;
cached_fack_count = fack_count;
if (i == first_sack_index) {
@@ -1213,7 +1216,9 @@
if (lost_retrans && icsk->icsk_ca_state == TCP_CA_Recovery) {
struct sk_buff *skb;
- sk_stream_for_retrans_queue(skb, sk) {
+ tcp_for_write_queue(skb, sk) {
+ if (skb == tcp_send_head(sk))
+ break;
if (after(TCP_SKB_CB(skb)->seq, lost_retrans))
break;
if (!after(TCP_SKB_CB(skb)->end_seq, tp->snd_una))
@@ -1266,8 +1271,8 @@
const struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
- if (!sysctl_tcp_frto || !sk->sk_send_head ||
- after(TCP_SKB_CB(sk->sk_send_head)->end_seq,
+ if (!sysctl_tcp_frto || !tcp_send_head(sk) ||
+ after(TCP_SKB_CB(tcp_send_head(sk))->end_seq,
tp->snd_una + tp->snd_wnd))
return 0;
@@ -1278,8 +1283,11 @@
if (tp->retrans_out > 1)
return 0;
- skb = skb_peek(&sk->sk_write_queue)->next; /* Skips head */
- sk_stream_for_retrans_queue_from(skb, sk) {
+ skb = tcp_write_queue_head(sk);
+ skb = tcp_write_queue_next(sk, skb); /* Skips head */
+ tcp_for_write_queue_from(skb, sk) {
+ if (skb == tcp_send_head(sk))
+ break;
if (TCP_SKB_CB(skb)->sacked&TCPCB_RETRANS)
return 0;
/* Short-circuit when first non-SACKed skb has been checked */
@@ -1343,7 +1351,7 @@
tp->undo_marker = tp->snd_una;
tp->undo_retrans = 0;
- skb = skb_peek(&sk->sk_write_queue);
+ skb = tcp_write_queue_head(sk);
if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_RETRANS) {
TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS;
tp->retrans_out -= tcp_skb_pcount(skb);
@@ -1380,7 +1388,9 @@
tp->fackets_out = 0;
tp->retrans_out = 0;
- sk_stream_for_retrans_queue(skb, sk) {
+ tcp_for_write_queue(skb, sk) {
+ if (skb == tcp_send_head(sk))
+ break;
cnt += tcp_skb_pcount(skb);
/*
* Count the retransmission made on RTO correctly (only when
@@ -1468,7 +1478,9 @@
if (!how)
tp->undo_marker = tp->snd_una;
- sk_stream_for_retrans_queue(skb, sk) {
+ tcp_for_write_queue(skb, sk) {
+ if (skb == tcp_send_head(sk))
+ break;
cnt += tcp_skb_pcount(skb);
if (TCP_SKB_CB(skb)->sacked&TCPCB_RETRANS)
tp->undo_marker = 0;
@@ -1503,14 +1515,14 @@
* receiver _host_ is heavily congested (or buggy).
* Do processing similar to RTO timeout.
*/
- if ((skb = skb_peek(&sk->sk_write_queue)) != NULL &&
+ if ((skb = tcp_write_queue_head(sk)) != NULL &&
(TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)) {
struct inet_connection_sock *icsk = inet_csk(sk);
NET_INC_STATS_BH(LINUX_MIB_TCPSACKRENEGING);
tcp_enter_loss(sk, 1);
icsk->icsk_retransmits++;
- tcp_retransmit_skb(sk, skb_peek(&sk->sk_write_queue));
+ tcp_retransmit_skb(sk, tcp_write_queue_head(sk));
inet_csk_reset_xmit_timer(sk, ICSK_TIME_RETRANS,
icsk->icsk_rto, TCP_RTO_MAX);
return 1;
@@ -1531,7 +1543,7 @@
static inline int tcp_head_timedout(struct sock *sk, struct tcp_sock *tp)
{
return tp->packets_out &&
- tcp_skb_timedout(sk, skb_peek(&sk->sk_write_queue));
+ tcp_skb_timedout(sk, tcp_write_queue_head(sk));
}
/* Linux NewReno/SACK/FACK/ECN state machine.
@@ -1726,11 +1738,13 @@
skb = tp->lost_skb_hint;
cnt = tp->lost_cnt_hint;
} else {
- skb = sk->sk_write_queue.next;
+ skb = tcp_write_queue_head(sk);
cnt = 0;
}
- sk_stream_for_retrans_queue_from(skb, sk) {
+ tcp_for_write_queue_from(skb, sk) {
+ if (skb == tcp_send_head(sk))
+ break;
/* TODO: do this better */
/* this is not the most efficient way to do this... */
tp->lost_skb_hint = skb;
@@ -1777,9 +1791,11 @@
struct sk_buff *skb;
skb = tp->scoreboard_skb_hint ? tp->scoreboard_skb_hint
- : sk->sk_write_queue.next;
+ : tcp_write_queue_head(sk);
- sk_stream_for_retrans_queue_from(skb, sk) {
+ tcp_for_write_queue_from(skb, sk) {
+ if (skb == tcp_send_head(sk))
+ break;
if (!tcp_skb_timedout(sk, skb))
break;
@@ -1970,7 +1986,9 @@
{
if (tcp_may_undo(tp)) {
struct sk_buff *skb;
- sk_stream_for_retrans_queue(skb, sk) {
+ tcp_for_write_queue(skb, sk) {
+ if (skb == tcp_send_head(sk))
+ break;
TCP_SKB_CB(skb)->sacked &= ~TCPCB_LOST;
}
@@ -2382,8 +2400,8 @@
= icsk->icsk_ca_ops->rtt_sample;
struct timeval tv = { .tv_sec = 0, .tv_usec = 0 };
- while ((skb = skb_peek(&sk->sk_write_queue)) &&
- skb != sk->sk_send_head) {
+ while ((skb = tcp_write_queue_head(sk)) &&
+ skb != tcp_send_head(sk)) {
struct tcp_skb_cb *scb = TCP_SKB_CB(skb);
__u8 sacked = scb->sacked;
@@ -2446,7 +2464,7 @@
}
tcp_dec_pcount_approx(&tp->fackets_out, skb);
tcp_packets_out_dec(tp, skb);
- __skb_unlink(skb, &sk->sk_write_queue);
+ tcp_unlink_write_queue(skb, sk);
sk_stream_free_skb(sk, skb);
clear_all_retrans_hints(tp);
}
@@ -2495,7 +2513,7 @@
/* Was it a usable window open? */
- if (!after(TCP_SKB_CB(sk->sk_send_head)->end_seq,
+ if (!after(TCP_SKB_CB(tcp_send_head(sk))->end_seq,
tp->snd_una + tp->snd_wnd)) {
icsk->icsk_backoff = 0;
inet_csk_clear_xmit_timer(sk, ICSK_TIME_PROBE0);
@@ -2795,7 +2813,7 @@
* being used to time the probes, and is probably far higher than
* it needs to be for normal retransmission.
*/
- if (sk->sk_send_head)
+ if (tcp_send_head(sk))
tcp_ack_probe(sk);
return 1;
