Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit a47e5a98 authored by Ilpo Järvinen's avatar Ilpo Järvinen Committed by David S. Miller
Browse files

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



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

Signed-off-by: default avatarIlpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 85cc391c

include/linux/tcp.h

+4 −2
Original line number Diff line number Diff line
@@ -332,8 +332,10 @@ struct tcp_sock { 


	struct tcp_sack_block_wire recv_sack_cache[4];



	u32	highest_sack;	/* Start seq of globally highest revd SACK

				 * (validity guaranteed only if sacked_out > 0) */

	struct sk_buff *highest_sack;   /* highest skb with SACK received

					 * (validity guaranteed only if

					 * sacked_out > 0)

					 */



	/* from STCP, retrans queue hinting */

	struct sk_buff* lost_skb_hint;

include/net/tcp.h

+10 −0
Original line number Diff line number Diff line
@@ -1312,6 +1312,16 @@ static inline int tcp_write_queue_empty(struct sock *sk) 
	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 */

enum tcp_seq_states {

	TCP_SEQ_STATE_LISTENING,

net/ipv4/tcp_input.c

+6 −6
Original line number Diff line number Diff line
@@ -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 reord = tp->packets_out;

	int prior_fackets;

	u32 highest_sack_end_seq = tp->lost_retrans_low;

	u32 highest_sack_end_seq;

	int flag = 0;

	int found_dup_sack = 0;

	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 (WARN_ON(tp->fackets_out))

			tp->fackets_out = 0;

		tp->highest_sack = tp->snd_una;

		tp->highest_sack = tcp_write_queue_head(sk);

	}

	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)

					tp->fackets_out = fack_count;



				if (after(TCP_SKB_CB(skb)->seq, tp->highest_sack)) {

					tp->highest_sack = TCP_SKB_CB(skb)->seq;

					highest_sack_end_seq = TCP_SKB_CB(skb)->end_seq;

				}

				if (after(TCP_SKB_CB(skb)->seq, tcp_highest_sack_seq(tp)))

					tp->highest_sack = skb;



			} else {

				if (dup_sack && (sacked&TCPCB_RETRANS))

					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;

	}



	highest_sack_end_seq = TCP_SKB_CB(tp->highest_sack)->end_seq;

	if (tcp_is_fack(tp) && tp->retrans_out &&

	    after(highest_sack_end_seq, tp->lost_retrans_low) &&

	    icsk->icsk_ca_state == TCP_CA_Recovery)

net/ipv4/tcp_output.c

+10 −9
Original line number Diff line number Diff line
@@ -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

 * 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)

{

	struct tcp_sock *tp = tcp_sk(sk);



	if (!tp->sacked_out || tcp_is_reno(tp))

		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;



	/* 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(skb)->end_seq = TCP_SKB_CB(buff)->seq;



	if (tcp_is_sack(tp) && tp->sacked_out &&

	    (TCP_SKB_CB(skb)->seq == tp->highest_sack))

		tp->highest_sack = TCP_SKB_CB(buff)->seq;

	if (tcp_is_sack(tp) && tp->sacked_out && (skb == tp->highest_sack))

		tp->highest_sack = buff;



	/* PSH and FIN should only be set in the second packet. */

	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_verify_left_out(tp);

		}

		tcp_adjust_fackets_out(tp, skb, diff);

		tcp_adjust_fackets_out(sk, skb, diff);

	}



	/* 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);



		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;



		/* 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)

			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);



		/* changed transmit queue under us so clear hints */
@@ -2028,7 +2029,7 @@ void tcp_xmit_retransmit_queue(struct sock *sk) 
			break;

		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;



		if (tcp_packets_in_flight(tp) >= tp->snd_cwnd)