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[TCP]: Convert highest_sack to sk_buff to allow direct access

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It is going to replace the sack fastpath hint quite soon... :-)

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 2007-11-15 19:41:46 -08:00 committed by David S. Miller
parent 85cc391c0e
commit a47e5a988a
4 changed files with 30 additions and 17 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

6
include/linux/tcp.h
View file

@ -332,8 +332,10 @@ struct tcp_sock {
struct tcp_sack_block_wire recv_sack_cache[4]; struct tcp_sack_block_wire recv_sack_cache[4];
u32 highest_sack; /* Start seq of globally highest revd SACK struct sk_buff *highest_sack; /* highest skb with SACK received
* (validity guaranteed only if sacked_out > 0) */ * (validity guaranteed only if
* sacked_out > 0)
*/
/* from STCP, retrans queue hinting */ /* from STCP, retrans queue hinting */
struct sk_buff* lost_skb_hint; struct sk_buff* lost_skb_hint;

10
include/net/tcp.h
View file

@ -1312,6 +1312,16 @@ static inline int tcp_write_queue_empty(struct sock *sk)
return skb_queue_empty(&sk->sk_write_queue); return skb_queue_empty(&sk->sk_write_queue);
} }
/* Start sequence of the highest skb with SACKed bit, valid only if
* sacked > 0 or when the caller has ensured validity by itself.
*/
static inline u32 tcp_highest_sack_seq(struct tcp_sock *tp)
{
if (!tp->sacked_out)
return tp->snd_una;
return TCP_SKB_CB(tp->highest_sack)->seq;
}
/* /proc */ /* /proc */
enum tcp_seq_states { enum tcp_seq_states {
TCP_SEQ_STATE_LISTENING, TCP_SEQ_STATE_LISTENING,

12
net/ipv4/tcp_input.c
View file

@ -1245,7 +1245,7 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
int num_sacks = (ptr[1] - TCPOLEN_SACK_BASE)>>3; int num_sacks = (ptr[1] - TCPOLEN_SACK_BASE)>>3;
int reord = tp->packets_out; int reord = tp->packets_out;
int prior_fackets; int prior_fackets;
u32 highest_sack_end_seq = tp->lost_retrans_low; u32 highest_sack_end_seq;
int flag = 0; int flag = 0;
int found_dup_sack = 0; int found_dup_sack = 0;
int cached_fack_count; int cached_fack_count;
@ -1256,7 +1256,7 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
if (!tp->sacked_out) { if (!tp->sacked_out) {
if (WARN_ON(tp->fackets_out)) if (WARN_ON(tp->fackets_out))
tp->fackets_out = 0; tp->fackets_out = 0;
tp->highest_sack = tp->snd_una; tp->highest_sack = tcp_write_queue_head(sk);
} }
prior_fackets = tp->fackets_out; prior_fackets = tp->fackets_out;
@ -1483,10 +1483,9 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
if (fack_count > tp->fackets_out) if (fack_count > tp->fackets_out)
tp->fackets_out = fack_count; tp->fackets_out = fack_count;
if (after(TCP_SKB_CB(skb)->seq, tp->highest_sack)) { if (after(TCP_SKB_CB(skb)->seq, tcp_highest_sack_seq(tp)))
tp->highest_sack = TCP_SKB_CB(skb)->seq; tp->highest_sack = skb;
highest_sack_end_seq = TCP_SKB_CB(skb)->end_seq;
}
} else { } else {
if (dup_sack && (sacked&TCPCB_RETRANS)) if (dup_sack && (sacked&TCPCB_RETRANS))
reord = min(fack_count, reord); reord = min(fack_count, reord);
@ -1514,6 +1513,7 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_
flag &= ~FLAG_ONLY_ORIG_SACKED; flag &= ~FLAG_ONLY_ORIG_SACKED;
} }
highest_sack_end_seq = TCP_SKB_CB(tp->highest_sack)->end_seq;
if (tcp_is_fack(tp) && tp->retrans_out && if (tcp_is_fack(tp) && tp->retrans_out &&
after(highest_sack_end_seq, tp->lost_retrans_low) && after(highest_sack_end_seq, tp->lost_retrans_low) &&
icsk->icsk_ca_state == TCP_CA_Recovery) icsk->icsk_ca_state == TCP_CA_Recovery)

19
net/ipv4/tcp_output.c
View file

@ -657,13 +657,15 @@ static void tcp_set_skb_tso_segs(struct sock *sk, struct sk_buff *skb, unsigned
* tweak SACK fastpath hint too as it would overwrite all changes unless * tweak SACK fastpath hint too as it would overwrite all changes unless
* hint is also changed. * hint is also changed.
*/ */
static void tcp_adjust_fackets_out(struct tcp_sock *tp, struct sk_buff *skb, static void tcp_adjust_fackets_out(struct sock *sk, struct sk_buff *skb,
int decr) int decr)
{ {
struct tcp_sock *tp = tcp_sk(sk);
if (!tp->sacked_out || tcp_is_reno(tp)) if (!tp->sacked_out || tcp_is_reno(tp))
return; return;
if (!before(tp->highest_sack, TCP_SKB_CB(skb)->seq)) if (!before(tcp_highest_sack_seq(tp), TCP_SKB_CB(skb)->seq))
tp->fackets_out -= decr; tp->fackets_out -= decr;
/* cnt_hint is "off-by-one" compared with fackets_out (see sacktag) */ /* cnt_hint is "off-by-one" compared with fackets_out (see sacktag) */
@ -712,9 +714,8 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss
TCP_SKB_CB(buff)->end_seq = TCP_SKB_CB(skb)->end_seq; TCP_SKB_CB(buff)->end_seq = TCP_SKB_CB(skb)->end_seq;
TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(buff)->seq; TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(buff)->seq;
if (tcp_is_sack(tp) && tp->sacked_out && if (tcp_is_sack(tp) && tp->sacked_out && (skb == tp->highest_sack))
(TCP_SKB_CB(skb)->seq == tp->highest_sack)) tp->highest_sack = buff;
tp->highest_sack = TCP_SKB_CB(buff)->seq;
/* PSH and FIN should only be set in the second packet. */ /* PSH and FIN should only be set in the second packet. */
flags = TCP_SKB_CB(skb)->flags; flags = TCP_SKB_CB(skb)->flags;
@ -772,7 +773,7 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss
tcp_dec_pcount_approx_int(&tp->sacked_out, diff); tcp_dec_pcount_approx_int(&tp->sacked_out, diff);
tcp_verify_left_out(tp); tcp_verify_left_out(tp);
} }
tcp_adjust_fackets_out(tp, skb, diff); tcp_adjust_fackets_out(sk, skb, diff);
} }
/* Link BUFF into the send queue. */ /* Link BUFF into the send queue. */
@ -1712,7 +1713,7 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int m
tcp_skb_pcount(next_skb) != 1); tcp_skb_pcount(next_skb) != 1);
if (WARN_ON(tcp_is_sack(tp) && tp->sacked_out && if (WARN_ON(tcp_is_sack(tp) && tp->sacked_out &&
(TCP_SKB_CB(next_skb)->seq == tp->highest_sack))) (next_skb == tp->highest_sack)))
return; return;
/* Ok. We will be able to collapse the packet. */ /* Ok. We will be able to collapse the packet. */
@ -1747,7 +1748,7 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int m
if (tcp_is_reno(tp) && tp->sacked_out) if (tcp_is_reno(tp) && tp->sacked_out)
tcp_dec_pcount_approx(&tp->sacked_out, next_skb); tcp_dec_pcount_approx(&tp->sacked_out, next_skb);
tcp_adjust_fackets_out(tp, next_skb, tcp_skb_pcount(next_skb)); tcp_adjust_fackets_out(sk, next_skb, tcp_skb_pcount(next_skb));
tp->packets_out -= tcp_skb_pcount(next_skb); tp->packets_out -= tcp_skb_pcount(next_skb);
/* changed transmit queue under us so clear hints */ /* changed transmit queue under us so clear hints */
@ -2028,7 +2029,7 @@ void tcp_xmit_retransmit_queue(struct sock *sk)
break; break;
tp->forward_skb_hint = skb; tp->forward_skb_hint = skb;
if (after(TCP_SKB_CB(skb)->seq, tp->highest_sack)) if (after(TCP_SKB_CB(skb)->seq, tcp_highest_sack_seq(tp)))
break; break;
if (tcp_packets_in_flight(tp) >= tp->snd_cwnd) if (tcp_packets_in_flight(tp) >= tp->snd_cwnd)