4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Yousuk Seung <ysseung@xxxxxxxxxx>
[ Upstream commit c634e34f6ebfb75259e6ce467523fd3adf30d3d2 ]
Pass a boolean flag that tells the ECE state of the current ack to reno
sack functions. This is pure refactor for future patches to improve
tracking delivered counts.
Signed-off-by: Yousuk Seung <ysseung@xxxxxxxxxx>
Signed-off-by: Yuchung Cheng <ycheng@xxxxxxxxxx>
Acked-by: Eric Dumazet <edumazet@xxxxxxxxxx>
Acked-by: Neal Cardwell <ncardwell@xxxxxxxxxx>
Acked-by: Soheil Hassas Yeganeh <soheil@xxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Stable-dep-of: a6458ab7fd4f ("UPSTREAM: tcp: fix DSACK undo in fast recovery to call tcp_try_to_open()")
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/ipv4/tcp_input.c | 22 ++++++++++++----------
1 file changed, 12 insertions(+), 10 deletions(-)
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index e51aa5a149c0f..88216b87c986f 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -1897,7 +1897,7 @@ static void tcp_check_reno_reordering(struct sock *sk, const int addend)
/* Emulate SACKs for SACKless connection: account for a new dupack. */
-static void tcp_add_reno_sack(struct sock *sk, int num_dupack)
+static void tcp_add_reno_sack(struct sock *sk, int num_dupack, bool ece_ack)
{
if (num_dupack) {
struct tcp_sock *tp = tcp_sk(sk);
@@ -1915,7 +1915,7 @@ static void tcp_add_reno_sack(struct sock *sk, int num_dupack)
/* Account for ACK, ACKing some data in Reno Recovery phase. */
-static void tcp_remove_reno_sacks(struct sock *sk, int acked)
+static void tcp_remove_reno_sacks(struct sock *sk, int acked, bool ece_ack)
{
struct tcp_sock *tp = tcp_sk(sk);
@@ -2720,7 +2720,7 @@ static void tcp_process_loss(struct sock *sk, int flag, int num_dupack,
* delivered. Lower inflight to clock out (re)tranmissions.
*/
if (after(tp->snd_nxt, tp->high_seq) && num_dupack)
- tcp_add_reno_sack(sk, num_dupack);
+ tcp_add_reno_sack(sk, num_dupack, flag & FLAG_ECE);
else if (flag & FLAG_SND_UNA_ADVANCED)
tcp_reset_reno_sack(tp);
}
@@ -2803,6 +2803,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una,
struct inet_connection_sock *icsk = inet_csk(sk);
struct tcp_sock *tp = tcp_sk(sk);
int fast_rexmit = 0, flag = *ack_flag;
+ bool ece_ack = flag & FLAG_ECE;
bool do_lost = num_dupack || ((flag & FLAG_DATA_SACKED) &&
tcp_force_fast_retransmit(sk));
@@ -2811,7 +2812,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una,
/* Now state machine starts.
* A. ECE, hence prohibit cwnd undoing, the reduction is required. */
- if (flag & FLAG_ECE)
+ if (ece_ack)
tp->prior_ssthresh = 0;
/* B. In all the states check for reneging SACKs. */
@@ -2852,7 +2853,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una,
case TCP_CA_Recovery:
if (!(flag & FLAG_SND_UNA_ADVANCED)) {
if (tcp_is_reno(tp))
- tcp_add_reno_sack(sk, num_dupack);
+ tcp_add_reno_sack(sk, num_dupack, ece_ack);
} else {
if (tcp_try_undo_partial(sk, prior_snd_una))
return;
@@ -2877,7 +2878,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una,
if (tcp_is_reno(tp)) {
if (flag & FLAG_SND_UNA_ADVANCED)
tcp_reset_reno_sack(tp);
- tcp_add_reno_sack(sk, num_dupack);
+ tcp_add_reno_sack(sk, num_dupack, ece_ack);
}
if (icsk->icsk_ca_state <= TCP_CA_Disorder)
@@ -2901,7 +2902,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una,
}
/* Otherwise enter Recovery state */
- tcp_enter_recovery(sk, (flag & FLAG_ECE));
+ tcp_enter_recovery(sk, ece_ack);
fast_rexmit = 1;
}
@@ -3077,7 +3078,7 @@ static void tcp_ack_tstamp(struct sock *sk, struct sk_buff *skb,
*/
static int tcp_clean_rtx_queue(struct sock *sk, u32 prior_fack,
u32 prior_snd_una,
- struct tcp_sacktag_state *sack)
+ struct tcp_sacktag_state *sack, bool ece_ack)
{
const struct inet_connection_sock *icsk = inet_csk(sk);
u64 first_ackt, last_ackt;
@@ -3215,7 +3216,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, u32 prior_fack,
}
if (tcp_is_reno(tp)) {
- tcp_remove_reno_sacks(sk, pkts_acked);
+ tcp_remove_reno_sacks(sk, pkts_acked, ece_ack);
/* If any of the cumulatively ACKed segments was
* retransmitted, non-SACK case cannot confirm that
@@ -3720,7 +3721,8 @@ static int tcp_ack(struct sock *sk, const struct sk_buff *skb, int flag)
goto no_queue;
/* See if we can take anything off of the retransmit queue. */
- flag |= tcp_clean_rtx_queue(sk, prior_fack, prior_snd_una, &sack_state);
+ flag |= tcp_clean_rtx_queue(sk, prior_fack, prior_snd_una, &sack_state,
+ flag & FLAG_ECE);
tcp_rack_update_reo_wnd(sk, &rs);
--
2.43.0
