1 files changed, 62 insertions, 29 deletions

diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index bbb3d39c69af..6ab82e1a1d41 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -292,7 +292,7 @@ EXPORT_PER_CPU_SYMBOL_GPL(tcp_orphan_count);
 long sysctl_tcp_mem[3] __read_mostly;
 EXPORT_SYMBOL(sysctl_tcp_mem);
 
-atomic_long_t tcp_memory_allocated;	/* Current allocated memory. */
+atomic_long_t tcp_memory_allocated ____cacheline_aligned_in_smp;	/* Current allocated memory. */
 EXPORT_SYMBOL(tcp_memory_allocated);
 
 #if IS_ENABLED(CONFIG_SMC)
@@ -303,7 +303,7 @@ EXPORT_SYMBOL(tcp_have_smc);
 /*
  * Current number of TCP sockets.
  */
-struct percpu_counter tcp_sockets_allocated;
+struct percpu_counter tcp_sockets_allocated ____cacheline_aligned_in_smp;
 EXPORT_SYMBOL(tcp_sockets_allocated);
 
 /*
@@ -456,7 +456,6 @@ void tcp_init_sock(struct sock *sk)
 	WRITE_ONCE(sk->sk_rcvbuf, sock_net(sk)->ipv4.sysctl_tcp_rmem[1]);
 
 	sk_sockets_allocated_inc(sk);
-	sk->sk_route_forced_caps = NETIF_F_GSO;
 }
 EXPORT_SYMBOL(tcp_init_sock);
 
@@ -546,10 +545,11 @@ __poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
 	if (state != TCP_SYN_SENT &&
 	    (state != TCP_SYN_RECV || rcu_access_pointer(tp->fastopen_rsk))) {
 		int target = sock_rcvlowat(sk, 0, INT_MAX);
+		u16 urg_data = READ_ONCE(tp->urg_data);
 
-		if (READ_ONCE(tp->urg_seq) == READ_ONCE(tp->copied_seq) &&
-		    !sock_flag(sk, SOCK_URGINLINE) &&
-		    tp->urg_data)
+		if (unlikely(urg_data) &&
+		    READ_ONCE(tp->urg_seq) == READ_ONCE(tp->copied_seq) &&
+		    !sock_flag(sk, SOCK_URGINLINE))
 			target++;
 
 		if (tcp_stream_is_readable(sk, target))
@@ -574,7 +574,7 @@ __poll_t tcp_poll(struct file *file, struct socket *sock, poll_table *wait)
 		} else
 			mask |= EPOLLOUT | EPOLLWRNORM;
 
-		if (tp->urg_data & TCP_URG_VALID)
+		if (urg_data & TCP_URG_VALID)
 			mask |= EPOLLPRI;
 	} else if (state == TCP_SYN_SENT && inet_sk(sk)->defer_connect) {
 		/* Active TCP fastopen socket with defer_connect
@@ -608,7 +608,7 @@ int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg)
 		unlock_sock_fast(sk, slow);
 		break;
 	case SIOCATMARK:
-		answ = tp->urg_data &&
+		answ = READ_ONCE(tp->urg_data) &&
 		       READ_ONCE(tp->urg_seq) == READ_ONCE(tp->copied_seq);
 		break;
 	case SIOCOUTQ:
@@ -1466,7 +1466,7 @@ static int tcp_recv_urg(struct sock *sk, struct msghdr *msg, int len, int flags)
 		char c = tp->urg_data;
 
 		if (!(flags & MSG_PEEK))
-			tp->urg_data = TCP_URG_READ;
+			WRITE_ONCE(tp->urg_data, TCP_URG_READ);
 
 		/* Read urgent data. */
 		msg->msg_flags |= MSG_OOB;
@@ -1580,6 +1580,36 @@ void tcp_cleanup_rbuf(struct sock *sk, int copied)
 		tcp_send_ack(sk);
 }
 
+void __sk_defer_free_flush(struct sock *sk)
+{
+	struct llist_node *head;
+	struct sk_buff *skb, *n;
+
+	head = llist_del_all(&sk->defer_list);
+	llist_for_each_entry_safe(skb, n, head, ll_node) {
+		prefetch(n);
+		skb_mark_not_on_list(skb);
+		__kfree_skb(skb);
+	}
+}
+EXPORT_SYMBOL(__sk_defer_free_flush);
+
+static void tcp_eat_recv_skb(struct sock *sk, struct sk_buff *skb)
+{
+	__skb_unlink(skb, &sk->sk_receive_queue);
+	if (likely(skb->destructor == sock_rfree)) {
+		sock_rfree(skb);
+		skb->destructor = NULL;
+		skb->sk = NULL;
+		if (!skb_queue_empty(&sk->sk_receive_queue) ||
+		    !llist_empty(&sk->defer_list)) {
+			llist_add(&skb->ll_node, &sk->defer_list);
+			return;
+		}
+	}
+	__kfree_skb(skb);
+}
+
 static struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off)
 {
 	struct sk_buff *skb;
@@ -1599,7 +1629,7 @@ static struct sk_buff *tcp_recv_skb(struct sock *sk, u32 seq, u32 *off)
 		 * splitted a fat GRO packet, while we released socket lock
 		 * in skb_splice_bits()
 		 */
-		sk_eat_skb(sk, skb);
+		tcp_eat_recv_skb(sk, skb);
 	}
 	return NULL;
 }
@@ -1633,7 +1663,7 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
 
 			len = skb->len - offset;
 			/* Stop reading if we hit a patch of urgent data */
-			if (tp->urg_data) {
+			if (unlikely(tp->urg_data)) {
 				u32 urg_offset = tp->urg_seq - seq;
 				if (urg_offset < len)
 					len = urg_offset;
@@ -1665,11 +1695,11 @@ int tcp_read_sock(struct sock *sk, read_descriptor_t *desc,
 				continue;
 		}
 		if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN) {
-			sk_eat_skb(sk, skb);
+			tcp_eat_recv_skb(sk, skb);
 			++seq;
 			break;
 		}
-		sk_eat_skb(sk, skb);
+		tcp_eat_recv_skb(sk, skb);
 		if (!desc->count)
 			break;
 		WRITE_ONCE(tp->copied_seq, seq);
@@ -2329,7 +2359,7 @@ static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len,
 		u32 offset;
 
 		/* Are we at urgent data? Stop if we have read anything or have SIGURG pending. */
-		if (tp->urg_data && tp->urg_seq == *seq) {
+		if (unlikely(tp->urg_data) && tp->urg_seq == *seq) {
 			if (copied)
 				break;
 			if (signal_pending(current)) {
@@ -2372,10 +2402,10 @@ static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len,
 			break;
 
 		if (copied) {
-			if (sk->sk_err ||
+			if (!timeo ||
+			    sk->sk_err ||
 			    sk->sk_state == TCP_CLOSE ||
 			    (sk->sk_shutdown & RCV_SHUTDOWN) ||
-			    !timeo ||
 			    signal_pending(current))
 				break;
 		} else {
@@ -2409,13 +2439,12 @@ static int tcp_recvmsg_locked(struct sock *sk, struct msghdr *msg, size_t len,
 			}
 		}
 
-		tcp_cleanup_rbuf(sk, copied);
-
 		if (copied >= target) {
 			/* Do not sleep, just process backlog. */
-			release_sock(sk);
-			lock_sock(sk);
+			__sk_flush_backlog(sk);
 		} else {
+			tcp_cleanup_rbuf(sk, copied);
+			sk_defer_free_flush(sk);
 			sk_wait_data(sk, &timeo, last);
 		}
 
@@ -2435,7 +2464,7 @@ found_ok_skb:
 			used = len;
 
 		/* Do we have urgent data here? */
-		if (tp->urg_data) {
+		if (unlikely(tp->urg_data)) {
 			u32 urg_offset = tp->urg_seq - *seq;
 			if (urg_offset < used) {
 				if (!urg_offset) {
@@ -2469,8 +2498,8 @@ found_ok_skb:
 		tcp_rcv_space_adjust(sk);
 
 skip_copy:
-		if (tp->urg_data && after(tp->copied_seq, tp->urg_seq)) {
-			tp->urg_data = 0;
+		if (unlikely(tp->urg_data) && after(tp->copied_seq, tp->urg_seq)) {
+			WRITE_ONCE(tp->urg_data, 0);
 			tcp_fast_path_check(sk);
 		}
 
@@ -2485,14 +2514,14 @@ skip_copy:
 		if (TCP_SKB_CB(skb)->tcp_flags & TCPHDR_FIN)
 			goto found_fin_ok;
 		if (!(flags & MSG_PEEK))
-			sk_eat_skb(sk, skb);
+			tcp_eat_recv_skb(sk, skb);
 		continue;
 
 found_fin_ok:
 		/* Process the FIN. */
 		WRITE_ONCE(*seq, *seq + 1);
 		if (!(flags & MSG_PEEK))
-			sk_eat_skb(sk, skb);
+			tcp_eat_recv_skb(sk, skb);
 		break;
 	} while (len > 0);
 
@@ -2534,6 +2563,7 @@ int tcp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int nonblock,
 	ret = tcp_recvmsg_locked(sk, msg, len, nonblock, flags, &tss,
 				 &cmsg_flags);
 	release_sock(sk);
+	sk_defer_free_flush(sk);
 
 	if (cmsg_flags && ret >= 0) {
 		if (cmsg_flags & TCP_CMSG_TS)
@@ -2964,7 +2994,7 @@ int tcp_disconnect(struct sock *sk, int flags)
 	tcp_clear_xmit_timers(sk);
 	__skb_queue_purge(&sk->sk_receive_queue);
 	WRITE_ONCE(tp->copied_seq, tp->rcv_nxt);
-	tp->urg_data = 0;
+	WRITE_ONCE(tp->urg_data, 0);
 	tcp_write_queue_purge(sk);
 	tcp_fastopen_active_disable_ofo_check(sk);
 	skb_rbtree_purge(&tp->out_of_order_queue);
@@ -3059,7 +3089,7 @@ int tcp_disconnect(struct sock *sk, int flags)
 		sk->sk_frag.page = NULL;
 		sk->sk_frag.offset = 0;
 	}
-
+	sk_defer_free_flush(sk);
 	sk_error_report(sk);
 	return 0;
 }
@@ -3774,10 +3804,12 @@ void tcp_get_info(struct sock *sk, struct tcp_info *info)
 	tcp_get_info_chrono_stats(tp, info);
 
 	info->tcpi_segs_out = tp->segs_out;
-	info->tcpi_segs_in = tp->segs_in;
+
+	/* segs_in and data_segs_in can be updated from tcp_segs_in() from BH */
+	info->tcpi_segs_in = READ_ONCE(tp->segs_in);
+	info->tcpi_data_segs_in = READ_ONCE(tp->data_segs_in);
 
 	info->tcpi_min_rtt = tcp_min_rtt(tp);
-	info->tcpi_data_segs_in = tp->data_segs_in;
 	info->tcpi_data_segs_out = tp->data_segs_out;
 
 	info->tcpi_delivery_rate_app_limited = tp->rate_app_limited ? 1 : 0;
@@ -4186,6 +4218,7 @@ static int do_tcp_getsockopt(struct sock *sk, int level,
 		err = BPF_CGROUP_RUN_PROG_GETSOCKOPT_KERN(sk, level, optname,
 							  &zc, &len, err);
 		release_sock(sk);
+		sk_defer_free_flush(sk);
 		if (len >= offsetofend(struct tcp_zerocopy_receive, msg_flags))
 			goto zerocopy_rcv_cmsg;
 		switch (len) {