[TCP]: Reduce sacked_out with reno when purging write_queue
Previously TCP had a transitional state during which reno counted segments that are already below the current window into sacked_out, which is now prevented. In addition, re-try now the unconditional S+L skb catching. This approach conservatively calls just remove_sack and leaves reset_sack() calls alone. The best solution to the whole problem would be to first calculate the new sacked_out fully (this patch does not move reno_sack_reset calls from original sites and thus does not implement this). However, that would require very invasive change to fastretrans_alert (perhaps even slicing it to two halves). Alternatively, all callers of tcp_packets_in_flight (i.e., users that depend on sacked_out) should be postponed until the new sacked_out has been calculated but it isn't any simpler alternative. Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@helsinki.fi> Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
parent
d02596e329
commit
1b6d427bb7
|
@ -759,8 +759,7 @@ static inline __u32 tcp_current_ssthresh(const struct sock *sk)
|
|||
}
|
||||
|
||||
/* Use define here intentionally to get BUG_ON location shown at the caller */
|
||||
#define tcp_verify_left_out(tp) \
|
||||
BUG_ON(tp->rx_opt.sack_ok && (tcp_left_out(tp) > tp->packets_out))
|
||||
#define tcp_verify_left_out(tp) BUG_ON(tcp_left_out(tp) > tp->packets_out)
|
||||
|
||||
extern void tcp_enter_cwr(struct sock *sk, const int set_ssthresh);
|
||||
extern __u32 tcp_init_cwnd(struct tcp_sock *tp, struct dst_entry *dst);
|
||||
|
|
|
@ -2187,7 +2187,7 @@ static void tcp_mtup_probe_success(struct sock *sk, struct sk_buff *skb)
|
|||
* tcp_xmit_retransmit_queue().
|
||||
*/
|
||||
static void
|
||||
tcp_fastretrans_alert(struct sock *sk, int prior_packets, int flag)
|
||||
tcp_fastretrans_alert(struct sock *sk, int pkts_acked, int flag)
|
||||
{
|
||||
struct inet_connection_sock *icsk = inet_csk(sk);
|
||||
struct tcp_sock *tp = tcp_sk(sk);
|
||||
|
@ -2273,12 +2273,8 @@ tcp_fastretrans_alert(struct sock *sk, int prior_packets, int flag)
|
|||
if (!(flag & FLAG_SND_UNA_ADVANCED)) {
|
||||
if (IsReno(tp) && is_dupack)
|
||||
tcp_add_reno_sack(sk);
|
||||
} else {
|
||||
int acked = prior_packets - tp->packets_out;
|
||||
if (IsReno(tp))
|
||||
tcp_remove_reno_sacks(sk, acked);
|
||||
do_lost = tcp_try_undo_partial(sk, acked);
|
||||
}
|
||||
} else
|
||||
do_lost = tcp_try_undo_partial(sk, pkts_acked);
|
||||
break;
|
||||
case TCP_CA_Loss:
|
||||
if (flag&FLAG_DATA_ACKED)
|
||||
|
@ -2577,6 +2573,9 @@ static int tcp_clean_rtx_queue(struct sock *sk, __s32 *seq_rtt_p)
|
|||
tcp_ack_update_rtt(sk, acked, seq_rtt);
|
||||
tcp_ack_packets_out(sk);
|
||||
|
||||
if (IsReno(tp))
|
||||
tcp_remove_reno_sacks(sk, pkts_acked);
|
||||
|
||||
if (ca_ops->pkts_acked) {
|
||||
s32 rtt_us = -1;
|
||||
|
||||
|
@ -2927,7 +2926,7 @@ static int tcp_ack(struct sock *sk, struct sk_buff *skb, int flag)
|
|||
if ((flag & FLAG_DATA_ACKED) && !frto_cwnd &&
|
||||
tcp_may_raise_cwnd(sk, flag))
|
||||
tcp_cong_avoid(sk, ack, prior_in_flight, 0);
|
||||
tcp_fastretrans_alert(sk, prior_packets, flag);
|
||||
tcp_fastretrans_alert(sk, prior_packets - tp->packets_out, flag);
|
||||
} else {
|
||||
if ((flag & FLAG_DATA_ACKED) && !frto_cwnd)
|
||||
tcp_cong_avoid(sk, ack, prior_in_flight, 1);
|
||||
|
|
Loading…
Reference in a new issue