forked from ~ljy/RK356X_SDK_RELEASE

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hc
2024-01-03 2f7c68cb55ecb7331f2381deb497c27155f32faf 
 kernel/net/ipv4/tcp_input.c
....@@ -243,6 +243,19 @@
243243 		if (unlikely(len > icsk->icsk_ack.rcv_mss +
244244 				   MAX_TCP_OPTION_SPACE))
245245 			tcp_gro_dev_warn(sk, skb, len);
246
+		/* If the skb has a len of exactly 1*MSS and has the PSH bit
247
+		 * set then it is likely the end of an application write. So
248
+		 * more data may not be arriving soon, and yet the data sender
249
+		 * may be waiting for an ACK if cwnd-bound or using TX zero
250
+		 * copy. So we set ICSK_ACK_PUSHED here so that
251
+		 * tcp_cleanup_rbuf() will send an ACK immediately if the app
252
+		 * reads all of the data and is not ping-pong. If len > MSS
253
+		 * then this logic does not matter (and does not hurt) because
254
+		 * tcp_cleanup_rbuf() will always ACK immediately if the app
255
+		 * reads data and there is more than an MSS of unACKed data.
256
+		 */
257
+		if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_PSH)
258
+			icsk->icsk_ack.pending |= ICSK_ACK_PUSHED;
246259 	} else {
247260 		/* Otherwise, we make more careful check taking into account,
248261 		 * that SACKs block is variable.
....@@ -287,7 +300,7 @@
287300 		icsk->icsk_ack.quick = quickacks;
288301 }
289302 
290
-void tcp_enter_quickack_mode(struct sock *sk, unsigned int max_quickacks)
303
+static void tcp_enter_quickack_mode(struct sock *sk, unsigned int max_quickacks)
291304 {
292305 	struct inet_connection_sock *icsk = inet_csk(sk);
293306 
....@@ -295,7 +308,6 @@
295308 	inet_csk_exit_pingpong_mode(sk);
296309 	icsk->icsk_ack.ato = TCP_ATO_MIN;
297310 }
298
-EXPORT_SYMBOL(tcp_enter_quickack_mode);
299311 
300312 /* Send ACKs quickly, if "quick" count is not exhausted
301313  * and the session is not interactive.
....@@ -3561,8 +3573,11 @@
35613573 static bool __tcp_oow_rate_limited(struct net *net, int mib_idx,
35623574 				   u32 *last_oow_ack_time)
35633575 {
3564
-	if (*last_oow_ack_time) {
3565
-		s32 elapsed = (s32)(tcp_jiffies32 - *last_oow_ack_time);
3576
+	/* Paired with the WRITE_ONCE() in this function. */
3577
+	u32 val = READ_ONCE(*last_oow_ack_time);
3578
+
3579
+	if (val) {
3580
+		s32 elapsed = (s32)(tcp_jiffies32 - val);
35663581 
35673582 		if (0 <= elapsed &&
35683583 		    elapsed < READ_ONCE(net->ipv4.sysctl_tcp_invalid_ratelimit)) {
....@@ -3571,7 +3586,10 @@
35713586 		}
35723587 	}
35733588 
3574
-	*last_oow_ack_time = tcp_jiffies32;
3589
+	/* Paired with the prior READ_ONCE() and with itself,
3590
+	 * as we might be lockless.
3591
+	 */
3592
+	WRITE_ONCE(*last_oow_ack_time, tcp_jiffies32);
35753593 
35763594 	return false;	/* not rate-limited: go ahead, send dupack now! */
35773595 }
....@@ -4324,7 +4342,7 @@
43244342 
43254343 	inet_csk_schedule_ack(sk);
43264344 
4327
-	sk->sk_shutdown |= RCV_SHUTDOWN;
4345
+	WRITE_ONCE(sk->sk_shutdown, sk->sk_shutdown | RCV_SHUTDOWN);
43284346 	sock_set_flag(sk, SOCK_DONE);
43294347 
43304348 	switch (sk->sk_state) {
....@@ -6506,7 +6524,7 @@
65066524 			break;
65076525 
65086526 		tcp_set_state(sk, TCP_FIN_WAIT2);
6509
-		sk->sk_shutdown |= SEND_SHUTDOWN;
6527
+		WRITE_ONCE(sk->sk_shutdown, sk->sk_shutdown | SEND_SHUTDOWN);
65106528 
65116529 		sk_dst_confirm(sk);
65126530