tcp/dccp: remove icsk->icsk_timeout

icsk->icsk_timeout can be replaced by icsk->icsk_retransmit_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/20250324203607.703850-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

6 files changed, 15 insertions, 14 deletions

diff --git a/net/dccp/timer.c b/net/dccp/timer.c
index a4cfb47b60e5..9fd14a336189 100644
--- a/net/dccp/timer.c
+++ b/net/dccp/timer.c
@@ -139,9 +139,9 @@ static void dccp_write_timer(struct timer_list *t)
 	if (sk->sk_state == DCCP_CLOSED || !icsk->icsk_pending)
 		goto out;
 
-	if (time_after(icsk->icsk_timeout, jiffies)) {
+	if (time_after(icsk_timeout(icsk), jiffies)) {
 		sk_reset_timer(sk, &icsk->icsk_retransmit_timer,
-			       icsk->icsk_timeout);
+			       icsk_timeout(icsk));
 		goto out;
 	}
 
diff --git a/net/ipv4/inet_diag.c b/net/ipv4/inet_diag.c
index efe2a085cf68..c2bb91d9e9ff 100644
--- a/net/ipv4/inet_diag.c
+++ b/net/ipv4/inet_diag.c
@@ -315,12 +315,12 @@ int inet_sk_diag_fill(struct sock *sk, struct inet_connection_sock *icsk,
 		r->idiag_timer = 1;
 		r->idiag_retrans = icsk->icsk_retransmits;
 		r->idiag_expires =
-			jiffies_delta_to_msecs(icsk->icsk_timeout - jiffies);
+			jiffies_delta_to_msecs(icsk_timeout(icsk) - jiffies);
 	} else if (icsk_pending == ICSK_TIME_PROBE0) {
 		r->idiag_timer = 4;
 		r->idiag_retrans = icsk->icsk_probes_out;
 		r->idiag_expires =
-			jiffies_delta_to_msecs(icsk->icsk_timeout - jiffies);
+			jiffies_delta_to_msecs(icsk_timeout(icsk) - jiffies);
 	} else if (timer_pending(&sk->sk_timer)) {
 		r->idiag_timer = 2;
 		r->idiag_retrans = icsk->icsk_probes_out;
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 1cd0938d47e0..8cce0d5489da 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -2923,10 +2923,10 @@ static void get_tcp4_sock(struct sock *sk, struct seq_file *f, int i)
 	    icsk_pending == ICSK_TIME_REO_TIMEOUT ||
 	    icsk_pending == ICSK_TIME_LOSS_PROBE) {
 		timer_active	= 1;
-		timer_expires	= icsk->icsk_timeout;
+		timer_expires	= icsk_timeout(icsk);
 	} else if (icsk_pending == ICSK_TIME_PROBE0) {
 		timer_active	= 4;
-		timer_expires	= icsk->icsk_timeout;
+		timer_expires	= icsk_timeout(icsk);
 	} else if (timer_pending(&sk->sk_timer)) {
 		timer_active	= 2;
 		timer_expires	= sk->sk_timer.expires;
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 728bce01ccd3..d828b74c3e73 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -509,7 +509,7 @@ static bool tcp_rtx_probe0_timed_out(const struct sock *sk,
 	 * and tp->rcv_tstamp might very well have been written recently.
 	 * rcv_delta can thus be negative.
 	 */
-	rcv_delta = icsk->icsk_timeout - tp->rcv_tstamp;
+	rcv_delta = icsk_timeout(icsk) - tp->rcv_tstamp;
 	if (rcv_delta <= timeout)
 		return false;
 
@@ -685,7 +685,8 @@ out:;
 }
 
 /* Called with bottom-half processing disabled.
-   Called by tcp_write_timer() */
+ * Called by tcp_write_timer() and tcp_release_cb().
+ */
 void tcp_write_timer_handler(struct sock *sk)
 {
 	struct inet_connection_sock *icsk = inet_csk(sk);
@@ -695,11 +696,11 @@ void tcp_write_timer_handler(struct sock *sk)
 	    !icsk->icsk_pending)
 		return;
 
-	if (time_after(icsk->icsk_timeout, jiffies)) {
-		sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout);
+	if (time_after(icsk_timeout(icsk), jiffies)) {
+		sk_reset_timer(sk, &icsk->icsk_retransmit_timer,
+			       icsk_timeout(icsk));
 		return;
 	}
-
 	tcp_mstamp_refresh(tcp_sk(sk));
 	event = icsk->icsk_pending;
 
diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c
index c134cf1a603a..b03c223eda4f 100644
--- a/net/ipv6/tcp_ipv6.c
+++ b/net/ipv6/tcp_ipv6.c
@@ -2195,10 +2195,10 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
 	    icsk_pending == ICSK_TIME_REO_TIMEOUT ||
 	    icsk_pending == ICSK_TIME_LOSS_PROBE) {
 		timer_active	= 1;
-		timer_expires	= icsk->icsk_timeout;
+		timer_expires	= icsk_timeout(icsk);
 	} else if (icsk_pending == ICSK_TIME_PROBE0) {
 		timer_active	= 4;
-		timer_expires	= icsk->icsk_timeout;
+		timer_expires	= icsk_timeout(icsk);
 	} else if (timer_pending(&sp->sk_timer)) {
 		timer_active	= 2;
 		timer_expires	= sp->sk_timer.expires;
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index ad780ae1d30d..1ac378ba1d67 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -422,7 +422,7 @@ static long mptcp_timeout_from_subflow(const struct mptcp_subflow_context *subfl
 	const struct sock *ssk = mptcp_subflow_tcp_sock(subflow);
 
 	return inet_csk(ssk)->icsk_pending && !subflow->stale_count ?
-	       inet_csk(ssk)->icsk_timeout - jiffies : 0;
+	       icsk_timeout(inet_csk(ssk)) - jiffies : 0;
 }
 
 static void mptcp_set_timeout(struct sock *sk)