leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

[TCP]: Avoid clearing sacktag hint in trivial situations

Browse Source 
There's no reason to clear the sacktag skb hint when small part
of the rexmit queue changes. Account changes (if any) instead when
fragmenting/collapsing. RTO/FRTO do not touch SACKED_ACKED bits so
no need to discard SACK tag hint at all.

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 2007-09-20 11:37:19 -07:00 committed by David S. Miller
parent c96fd3d461
commit b76892051c
3 changed files with 21 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
include/net/tcp.h
View File

@ -1067,11 +1067,15 @@ static inline void tcp_mib_init(void)
}
/* from STCP */
static inline void tcp_clear_all_retrans_hints(struct tcp_sock *tp) {
static inline void tcp_clear_retrans_hints_partial(struct tcp_sock *tp) {
tp->lost_skb_hint = NULL;
tp->scoreboard_skb_hint = NULL;
tp->retransmit_skb_hint = NULL;
tp->forward_skb_hint = NULL;
}
static inline void tcp_clear_all_retrans_hints(struct tcp_sock *tp) {
tcp_clear_retrans_hints_partial(tp);
tp->fastpath_skb_hint = NULL;
}

14
net/ipv4/tcp_input.c
View File

@ -1671,7 +1671,7 @@ static void tcp_enter_frto_loss(struct sock *sk, int allowed_segments, int flag)
tp->high_seq = tp->frto_highmark;
TCP_ECN_queue_cwr(tp);
tcp_clear_all_retrans_hints(tp);
tcp_clear_retrans_hints_partial(tp);
}
void tcp_clear_retrans(struct tcp_sock *tp)
@ -1711,10 +1711,14 @@ void tcp_enter_loss(struct sock *sk, int how)
tp->bytes_acked = 0;
tcp_clear_retrans(tp);
/* Push undo marker, if it was plain RTO and nothing
* was retransmitted. */
if (!how)
if (!how) {
/* Push undo marker, if it was plain RTO and nothing
* was retransmitted. */
tp->undo_marker = tp->snd_una;
tcp_clear_retrans_hints_partial(tp);
} else {
tcp_clear_all_retrans_hints(tp);
}
tcp_for_write_queue(skb, sk) {
if (skb == tcp_send_head(sk))
@ -1741,8 +1745,6 @@ void tcp_enter_loss(struct sock *sk, int how)
TCP_ECN_queue_cwr(tp);
/* Abort FRTO algorithm if one is in progress */
tp->frto_counter = 0;
tcp_clear_all_retrans_hints(tp);
}
static int tcp_check_sack_reneging(struct sock *sk)

12
net/ipv4/tcp_output.c
View File

@ -687,7 +687,7 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss
BUG_ON(len > skb->len);
tcp_clear_all_retrans_hints(tp);
tcp_clear_retrans_hints_partial(tp);
nsize = skb_headlen(skb) - len;
if (nsize < 0)
nsize = 0;
@ -1718,9 +1718,6 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int m
BUG_ON(tcp_skb_pcount(skb) != 1 ||
tcp_skb_pcount(next_skb) != 1);
/* changing transmit queue under us so clear hints */
tcp_clear_all_retrans_hints(tp);
/* Ok. We will be able to collapse the packet. */
tcp_unlink_write_queue(next_skb, sk);
@ -1759,6 +1756,13 @@ static void tcp_retrans_try_collapse(struct sock *sk, struct sk_buff *skb, int m
tcp_adjust_fackets_out(tp, 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);
/* manually tune sacktag skb hint */
if (tp->fastpath_skb_hint == next_skb)
tp->fastpath_skb_hint = skb;
sk_stream_free_skb(sk, next_skb);
}
}