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>

diff --git a/Documentation/networking/net_cachelines/inet_connection_sock.rst b/Documentation/networking/net_cachelines/inet_connection_sock.rst
index b2401aa7c45090b07c2262ac31a3584725f92233..5fb0dd70c9af76ca68b3406ce76d4b61957c7da9 100644 (file)
--- a/Documentation/networking/net_cachelines/inet_connection_sock.rst
+++ b/Documentation/networking/net_cachelines/inet_connection_sock.rst
@@ -12,8 +12,7 @@ struct inet_sock                    icsk_inet              read_mostly         r
 struct request_sock_queue           icsk_accept_queue
 struct inet_bind_bucket             icsk_bind_hash         read_mostly                             tcp_set_state
 struct inet_bind2_bucket            icsk_bind2_hash        read_mostly                             tcp_set_state,inet_put_port
-unsigned_long                       icsk_timeout           read_mostly                             inet_csk_reset_xmit_timer,tcp_connect
-struct timer_list                   icsk_retransmit_timer  read_mostly                             inet_csk_reset_xmit_timer,tcp_connect
+struct timer_list                   icsk_retransmit_timer  read_write                              inet_csk_reset_xmit_timer,tcp_connect
 struct timer_list                   icsk_delack_timer      read_mostly                             inet_csk_reset_xmit_timer,tcp_connect
 u32                                 icsk_rto               read_write                              tcp_cwnd_validate,tcp_schedule_loss_probe,tcp_connect_init,tcp_connect,tcp_write_xmit,tcp_push_one
 u32                                 icsk_rto_min

diff --git a/include/net/inet_connection_sock.h b/include/net/inet_connection_sock.h
index 09a9d333fa42a6bf119eb98d75e88315d8c40079..6dca0ac6fbc6f50be447e2a554593c77bd9cf1b6 100644 (file)
--- a/include/net/inet_connection_sock.h
+++ b/include/net/inet_connection_sock.h
@@ -56,7 +56,6 @@ struct inet_connection_sock_af_ops {
  * @icsk_accept_queue:    FIFO of established children
  * @icsk_bind_hash:       Bind node
  * @icsk_bind2_hash:      Bind node in the bhash2 table
- * @icsk_timeout:         Timeout
  * @icsk_retransmit_timer: Resend (no ack)
  * @icsk_rto:             Retransmit timeout
  * @icsk_pmtu_cookie      Last pmtu seen by socket
@@ -82,7 +81,6 @@ struct inet_connection_sock {
        struct request_sock_queue icsk_accept_queue;
        struct inet_bind_bucket   *icsk_bind_hash;
        struct inet_bind2_bucket  *icsk_bind2_hash;
-       unsigned long             icsk_timeout;
        struct timer_list         icsk_retransmit_timer;
        struct timer_list         icsk_delack_timer;
        __u32                     icsk_rto;
@@ -187,6 +185,12 @@ static inline void inet_csk_delack_init(struct sock *sk)
        memset(&inet_csk(sk)->icsk_ack, 0, sizeof(inet_csk(sk)->icsk_ack));
 }
 
+static inline unsigned long
+icsk_timeout(const struct inet_connection_sock *icsk)
+{
+       return READ_ONCE(icsk->icsk_retransmit_timer.expires);
+}
+
 static inline void inet_csk_clear_xmit_timer(struct sock *sk, const int what)
 {
        struct inet_connection_sock *icsk = inet_csk(sk);
@@ -225,8 +229,8 @@ static inline void inet_csk_reset_xmit_timer(struct sock *sk, const int what,
        if (what == ICSK_TIME_RETRANS || what == ICSK_TIME_PROBE0 ||
            what == ICSK_TIME_LOSS_PROBE || what == ICSK_TIME_REO_TIMEOUT) {
                smp_store_release(&icsk->icsk_pending, what);
-               icsk->icsk_timeout = jiffies + when;
-               sk_reset_timer(sk, &icsk->icsk_retransmit_timer, icsk->icsk_timeout);
+               when += jiffies;
+               sk_reset_timer(sk, &icsk->icsk_retransmit_timer, when);
        } else if (what == ICSK_TIME_DACK) {
                smp_store_release(&icsk->icsk_ack.pending,
                                  icsk->icsk_ack.pending | ICSK_ACK_TIMER);

diff --git a/net/dccp/timer.c b/net/dccp/timer.c
index a4cfb47b60e523bd4a8f1f47cfedc11e633945c6..9fd14a3361893d5f2d9f0ad18a65cff963cc7e22 100644 (file)
--- 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 efe2a085cf68e90cd1e79b5556e667a0fd044bfd..c2bb91d9e9ffd1fc7dc9bf048c1d6bbd75462997 100644 (file)
--- 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 1cd0938d47e07e062a14cef1442edfb8a12c6140..8cce0d5489daeb21c3384e44752acd84ec0eb3e9 100644 (file)
--- 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 728bce01ccd3ddb1f374fa96b86434a415dbe2cb..d828b74c3e73d75cdae777645e8e8856c0751201 100644 (file)
--- 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 c134cf1a603a0aae462399813b2132c8c2897837..b03c223eda4fa3f4ad47a84224a24c32f02571fc 100644 (file)
--- 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 ad780ae1d30dcb6ff72960b340e1472a1400618a..1ac378ba1d67cd17449ab6c4b4793b65d520ec44 100644 (file)
--- 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)

diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_tcp4.c b/tools/testing/selftests/bpf/progs/bpf_iter_tcp4.c
index d22449c69363afe3c3aaae158f0ef0c6ef65916c..164640db3a29cf720e193453cab79f4bc317917c 100644 (file)
--- a/tools/testing/selftests/bpf/progs/bpf_iter_tcp4.c
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_tcp4.c
@@ -99,10 +99,10 @@ static int dump_tcp_sock(struct seq_file *seq, struct tcp_sock *tp,
            icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT ||
            icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {
                timer_active = 1;
-               timer_expires = icsk->icsk_timeout;
+               timer_expires = icsk->icsk_retransmit_timer.expires;
        } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
                timer_active = 4;
-               timer_expires = icsk->icsk_timeout;
+               timer_expires = icsk->icsk_retransmit_timer.expires;
        } else if (timer_pending(&sp->sk_timer)) {
                timer_active = 2;
                timer_expires = sp->sk_timer.expires;

diff --git a/tools/testing/selftests/bpf/progs/bpf_iter_tcp6.c b/tools/testing/selftests/bpf/progs/bpf_iter_tcp6.c
index 8b072666f9d9a0ce023e7cb2c2716bf4a5bd3905..591c703f5032f024e4b511a6af8d63d1233a042a 100644 (file)
--- a/tools/testing/selftests/bpf/progs/bpf_iter_tcp6.c
+++ b/tools/testing/selftests/bpf/progs/bpf_iter_tcp6.c
@@ -99,10 +99,10 @@ static int dump_tcp6_sock(struct seq_file *seq, struct tcp6_sock *tp,
            icsk->icsk_pending == ICSK_TIME_REO_TIMEOUT ||
            icsk->icsk_pending == ICSK_TIME_LOSS_PROBE) {
                timer_active = 1;
-               timer_expires = icsk->icsk_timeout;
+               timer_expires = icsk->icsk_retransmit_timer.expires;
        } else if (icsk->icsk_pending == ICSK_TIME_PROBE0) {
                timer_active = 4;
-               timer_expires = icsk->icsk_timeout;
+               timer_expires = icsk->icsk_retransmit_timer.expires;
        } else if (timer_pending(&sp->sk_timer)) {
                timer_active = 2;
                timer_expires = sp->sk_timer.expires;