diff options
| author | Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> | 2007-12-31 04:49:21 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-01-28 15:00:23 -0800 |
| commit | cadbd0313bc897f5917d013174cdf9077edf4aa5 (patch) | |
| tree | d9e147c4ef0bf944d642f269db34050d5ee0fc89 /net/ipv4/tcp_input.c | |
| parent | 90840defabbd819180c7528e12d550776848f833 (diff) | |
[TCP]: Dropped unnecessary skb/sacked accessing in reneging
SACK reneging can be precalculated to a FLAG in clean_rtx_queue
which has the right skb looked up. This will help a bit in
future because skb->sacked access will be changed eventually,
changing it already won't hurt any.
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/tcp_input.c')
| -rw-r--r-- | net/ipv4/tcp_input.c | 25 |
1 files changed, 13 insertions, 12 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 366f63ae4d5c..7bac1fac065f 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -105,6 +105,7 @@ int sysctl_tcp_abc __read_mostly; #define FLAG_SND_UNA_ADVANCED 0x400 /* Snd_una was changed (!= FLAG_DATA_ACKED) */ #define FLAG_DSACKING_ACK 0x800 /* SACK blocks contained D-SACK info */ #define FLAG_NONHEAD_RETRANS_ACKED 0x1000 /* Non-head rexmitted data was ACKed */ +#define FLAG_SACK_RENEGING 0x2000 /* snd_una advanced to a sacked seq */ #define FLAG_ACKED (FLAG_DATA_ACKED|FLAG_SYN_ACKED) #define FLAG_NOT_DUP (FLAG_DATA|FLAG_WIN_UPDATE|FLAG_ACKED) @@ -1918,18 +1919,15 @@ void tcp_enter_loss(struct sock *sk, int how) tp->frto_counter = 0; } -static int tcp_check_sack_reneging(struct sock *sk) +/* If ACK arrived pointing to a remembered SACK, it means that our + * remembered SACKs do not reflect real state of receiver i.e. + * receiver _host_ is heavily congested (or buggy). + * + * Do processing similar to RTO timeout. + */ +static int tcp_check_sack_reneging(struct sock *sk, int flag) { - struct sk_buff *skb; - - /* If ACK arrived pointing to a remembered SACK, - * it means that our remembered SACKs do not reflect - * real state of receiver i.e. - * receiver _host_ is heavily congested (or buggy). - * Do processing similar to RTO timeout. - */ - if ((skb = tcp_write_queue_head(sk)) != NULL && - (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)) { + if (flag & FLAG_SACK_RENEGING) { struct inet_connection_sock *icsk = inet_csk(sk); NET_INC_STATS_BH(LINUX_MIB_TCPSACKRENEGING); @@ -2515,7 +2513,7 @@ tcp_fastretrans_alert(struct sock *sk, int pkts_acked, int flag) tp->prior_ssthresh = 0; /* B. In all the states check for reneging SACKs. */ - if (tp->sacked_out && tcp_check_sack_reneging(sk)) + if (tcp_check_sack_reneging(sk, flag)) return; /* C. Process data loss notification, provided it is valid. */ @@ -2852,6 +2850,9 @@ static int tcp_clean_rtx_queue(struct sock *sk, int prior_fackets) tcp_clear_all_retrans_hints(tp); } + if (skb && (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)) + flag |= FLAG_SACK_RENEGING; + if (flag & FLAG_ACKED) { const struct tcp_congestion_ops *ca_ops = inet_csk(sk)->icsk_ca_ops; |