tcp/dccp: remove icsk->icsk_ack.timeout

icsk->icsk_ack.timeout can be replaced by icsk->csk_delack_timer.expires

This saves 8 bytes in TCP/DCCP sockets and helps for better cache locality.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20250324203607.703850-3-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

6 files changed, 10 insertions, 13 deletions

diff --git a/net/dccp/output.c b/net/dccp/output.c
index 5c2e24f3c39b..39cf3430177a 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -627,11 +627,10 @@ void dccp_send_delayed_ack(struct sock *sk)
 			return;
 		}
 
-		if (!time_before(timeout, icsk->icsk_ack.timeout))
-			timeout = icsk->icsk_ack.timeout;
+		if (!time_before(timeout, icsk_delack_timeout(icsk)))
+			timeout = icsk_delack_timeout(icsk);
 	}
 	icsk->icsk_ack.pending |= ICSK_ACK_SCHED | ICSK_ACK_TIMER;
-	icsk->icsk_ack.timeout = timeout;
 	sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout);
 }
 #endif
diff --git a/net/dccp/timer.c b/net/dccp/timer.c
index 9fd14a336189..232ac4ae0a73 100644
--- a/net/dccp/timer.c
+++ b/net/dccp/timer.c
@@ -185,9 +185,9 @@ static void dccp_delack_timer(struct timer_list *t)
 	if (sk->sk_state == DCCP_CLOSED ||
 	    !(icsk->icsk_ack.pending & ICSK_ACK_TIMER))
 		goto out;
-	if (time_after(icsk->icsk_ack.timeout, jiffies)) {
+	if (time_after(icsk_delack_timeout(icsk), jiffies)) {
 		sk_reset_timer(sk, &icsk->icsk_delack_timer,
-			       icsk->icsk_ack.timeout);
+			       icsk_delack_timeout(icsk));
 		goto out;
 	}
 
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index 9a6061017114..13295a59d22e 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -4225,17 +4225,16 @@ void tcp_send_delayed_ack(struct sock *sk)
 	/* Use new timeout only if there wasn't a older one earlier. */
 	if (icsk->icsk_ack.pending & ICSK_ACK_TIMER) {
 		/* If delack timer is about to expire, send ACK now. */
-		if (time_before_eq(icsk->icsk_ack.timeout, jiffies + (ato >> 2))) {
+		if (time_before_eq(icsk_delack_timeout(icsk), jiffies + (ato >> 2))) {
 			tcp_send_ack(sk);
 			return;
 		}
 
-		if (!time_before(timeout, icsk->icsk_ack.timeout))
-			timeout = icsk->icsk_ack.timeout;
+		if (!time_before(timeout, icsk_delack_timeout(icsk)))
+			timeout = icsk_delack_timeout(icsk);
 	}
 	smp_store_release(&icsk->icsk_ack.pending,
 			  icsk->icsk_ack.pending | ICSK_ACK_SCHED | ICSK_ACK_TIMER);
-	icsk->icsk_ack.timeout = timeout;
 	sk_reset_timer(sk, &icsk->icsk_delack_timer, timeout);
 }
 
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index d828b74c3e73..d64383b06a29 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -322,8 +322,9 @@ void tcp_delack_timer_handler(struct sock *sk)
 	if (!(icsk->icsk_ack.pending & ICSK_ACK_TIMER))
 		return;
 
-	if (time_after(icsk->icsk_ack.timeout, jiffies)) {
-		sk_reset_timer(sk, &icsk->icsk_delack_timer, icsk->icsk_ack.timeout);
+	if (time_after(icsk_delack_timeout(icsk), jiffies)) {
+		sk_reset_timer(sk, &icsk->icsk_delack_timer,
+			       icsk_delack_timeout(icsk));
 		return;
 	}
 	icsk->icsk_ack.pending &= ~ICSK_ACK_TIMER;
diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 23949ae2a3a8..421ced031289 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -432,7 +432,6 @@ static void clear_3rdack_retransmission(struct sock *sk)
 	struct inet_connection_sock *icsk = inet_csk(sk);
 
 	sk_stop_timer(sk, &icsk->icsk_delack_timer);
-	icsk->icsk_ack.timeout = 0;
 	icsk->icsk_ack.ato = 0;
 	icsk->icsk_ack.pending &= ~(ICSK_ACK_SCHED | ICSK_ACK_TIMER);
 }
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 1ac378ba1d67..44f7ab463d75 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -3420,7 +3420,6 @@ static void schedule_3rdack_retransmission(struct sock *ssk)
 	WARN_ON_ONCE(icsk->icsk_ack.pending & ICSK_ACK_TIMER);
 	smp_store_release(&icsk->icsk_ack.pending,
 			  icsk->icsk_ack.pending | ICSK_ACK_SCHED | ICSK_ACK_TIMER);
-	icsk->icsk_ack.timeout = timeout;
 	sk_reset_timer(ssk, &icsk->icsk_delack_timer, timeout);
 }