Home Home > GIT Browse
summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorIlpo Järvinen <ilpo.jarvinen@helsinki.fi>2007-09-20 13:10:25 -0700
committerGreg Kroah-Hartman <gregkh@suse.de>2007-09-26 10:54:43 -0700
commiteb7bdad82e8af48e1ed1b650268dc85ca7e9ff39 (patch)
treec06db70f54caf938fe52938c459d2f5ea453d687
parent8f67cd4be96512bc7b415e55be2e061dcce5664a (diff)
Handle snd_una in tcp_cwnd_down()
commit 6ee8009e38006da81d2a53da1aaa27365552553e in mainline Subject: [PATCH 1/1] [TCP]: Also handle snd_una changes in tcp_cwnd_down tcp_cwnd_down must check for it too as it should be conservative in case of collapse stuff and also when receiver is trying to lie (though it wouldn't be successful anyway). Note: - Separated also is_dupack and do_lost in fast_retransalert * Much cleaner look-and-feel now * This time it really fixes cumulative ACK + many new SACK blocks recovery entry (I claimed this fixes with last patch but it wasn't). TCP will now call tcp_update_scoreboard regardless of is_dupack when in recovery as long as there is enough fackets_out. - Introduce FLAG_SND_UNA_ADVANCED * Some prior_snd_una arguments are unnecessary after it - Added helper FLAG_ANY_PROGRESS to avoid long FLAG...|FLAG... constructs This is a reduced version of a mainline patch. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Cc: David Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r--net/ipv4/tcp_input.c18
1 files changed, 11 insertions, 7 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 13abf4eaa051..091b0617d5b7 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -102,11 +102,13 @@ int sysctl_tcp_abc __read_mostly;
#define FLAG_DATA_LOST 0x80 /* SACK detected data lossage. */
#define FLAG_SLOWPATH 0x100 /* Do not skip RFC checks for window update.*/
#define FLAG_ONLY_ORIG_SACKED 0x200 /* SACKs only non-rexmit sent before RTO */
+#define FLAG_SND_UNA_ADVANCED 0x400 /* Snd_una was changed (!= FLAG_DATA_ACKED) */
#define FLAG_ACKED (FLAG_DATA_ACKED|FLAG_SYN_ACKED)
#define FLAG_NOT_DUP (FLAG_DATA|FLAG_WIN_UPDATE|FLAG_ACKED)
#define FLAG_CA_ALERT (FLAG_DATA_SACKED|FLAG_ECE)
#define FLAG_FORWARD_PROGRESS (FLAG_ACKED|FLAG_DATA_SACKED)
+#define FLAG_ANY_PROGRESS (FLAG_FORWARD_PROGRESS|FLAG_SND_UNA_ADVANCED)
#define IsReno(tp) ((tp)->rx_opt.sack_ok == 0)
#define IsFack(tp) ((tp)->rx_opt.sack_ok & 2)
@@ -1856,7 +1858,7 @@ static void tcp_cwnd_down(struct sock *sk, int flag)
struct tcp_sock *tp = tcp_sk(sk);
int decr = tp->snd_cwnd_cnt + 1;
- if ((flag&FLAG_FORWARD_PROGRESS) ||
+ if ((flag&FLAG_ANY_PROGRESS) ||
(IsReno(tp) && !(flag&FLAG_NOT_DUP))) {
tp->snd_cwnd_cnt = decr&1;
decr >>= 1;
@@ -2112,10 +2114,9 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
{
struct inet_connection_sock *icsk = inet_csk(sk);
struct tcp_sock *tp = tcp_sk(sk);
- int is_dupack = (tp->snd_una == prior_snd_una &&
- (!(flag&FLAG_NOT_DUP) ||
- ((flag&FLAG_DATA_SACKED) &&
- (tp->fackets_out > tp->reordering))));
+ int is_dupack = !(flag&(FLAG_SND_UNA_ADVANCED|FLAG_NOT_DUP));
+ int do_lost = is_dupack || ((flag&FLAG_DATA_SACKED) &&
+ (tp->fackets_out > tp->reordering));
/* Some technical things:
* 1. Reno does not count dupacks (sacked_out) automatically. */
@@ -2199,7 +2200,7 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
int acked = prior_packets - tp->packets_out;
if (IsReno(tp))
tcp_remove_reno_sacks(sk, acked);
- is_dupack = tcp_try_undo_partial(sk, acked);
+ do_lost = tcp_try_undo_partial(sk, acked);
}
break;
case TCP_CA_Loss:
@@ -2264,7 +2265,7 @@ tcp_fastretrans_alert(struct sock *sk, u32 prior_snd_una,
tcp_set_ca_state(sk, TCP_CA_Recovery);
}
- if (is_dupack || tcp_head_timedout(sk))
+ if (do_lost || tcp_head_timedout(sk))
tcp_update_scoreboard(sk);
tcp_cwnd_down(sk, flag);
tcp_xmit_retransmit_queue(sk);
@@ -2774,6 +2775,9 @@ static int tcp_ack(struct sock *sk, struct sk_buff *skb, int flag)
if (before(ack, prior_snd_una))
goto old_ack;
+ if (after(ack, prior_snd_una))
+ flag |= FLAG_SND_UNA_ADVANCED;
+
if (sysctl_tcp_abc) {
if (icsk->icsk_ca_state < TCP_CA_CWR)
tp->bytes_acked += ack - prior_snd_una;