tcp: Remove debug macro of TCP_CHECK_TIMER

Now, TCP_CHECK_TIMER is not used for debuging, it does nothing.
And, it has been there for several years, maybe 6 years.

Remove it to keep code clearer.

Signed-off-by: Shan Wei <shanwei@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/tcp.h

@@ -1068,8 +1068,6 @@ static inline int tcp_paws_reject(const struct tcp_options_received *rx_opt,
 	return 1;
 }
 
-#define TCP_CHECK_TIMER(sk) do { } while (0)
-
 static inline void tcp_mib_init(struct net *net)
 {
 	/* See RFC 2012 */

net/ipv4/tcp.c

@@ -873,9 +873,7 @@ int tcp_sendpage(struct sock *sk, struct page *page, int offset,
 					flags);
 
 	lock_sock(sk);
-	TCP_CHECK_TIMER(sk);
 	res = do_tcp_sendpages(sk, &page, offset, size, flags);
-	TCP_CHECK_TIMER(sk);
 	release_sock(sk);
 	return res;
 }
@@ -916,7 +914,6 @@ int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 	long timeo;
 
 	lock_sock(sk);
-	TCP_CHECK_TIMER(sk);
 
 	flags = msg->msg_flags;
 	timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
@@ -1104,7 +1101,6 @@ wait_for_memory:
 out:
 	if (copied)
 		tcp_push(sk, flags, mss_now, tp->nonagle);
-	TCP_CHECK_TIMER(sk);
 	release_sock(sk);
 	return copied;
 
@@ -1123,7 +1119,6 @@ do_error:
 		goto out;
 out_err:
 	err = sk_stream_error(sk, flags, err);
-	TCP_CHECK_TIMER(sk);
 	release_sock(sk);
 	return err;
 }
@@ -1415,8 +1410,6 @@ int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg,
 
 	lock_sock(sk);
 
-	TCP_CHECK_TIMER(sk);
-
 	err = -ENOTCONN;
 	if (sk->sk_state == TCP_LISTEN)
 		goto out;
@@ -1767,12 +1760,10 @@ skip_copy:
 	/* Clean up data we have read: This will do ACK frames. */
 	tcp_cleanup_rbuf(sk, copied);
 
-	TCP_CHECK_TIMER(sk);
 	release_sock(sk);
 	return copied;
 
 out:
-	TCP_CHECK_TIMER(sk);
 	release_sock(sk);
 	return err;
 

net/ipv4/tcp_ipv4.c

@@ -1556,12 +1556,10 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
 
 	if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
 		sock_rps_save_rxhash(sk, skb->rxhash);
-		TCP_CHECK_TIMER(sk);
 		if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len)) {
 			rsk = sk;
 			goto reset;
 		}
-		TCP_CHECK_TIMER(sk);
 		return 0;
 	}
 
@@ -1583,13 +1581,10 @@ int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb)
 	} else
 		sock_rps_save_rxhash(sk, skb->rxhash);
 
-
-	TCP_CHECK_TIMER(sk);
 	if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len)) {
 		rsk = sk;
 		goto reset;
 	}
-	TCP_CHECK_TIMER(sk);
 	return 0;
 
 reset:

net/ipv4/tcp_timer.c

@@ -259,7 +259,6 @@ static void tcp_delack_timer(unsigned long data)
 		tcp_send_ack(sk);
 		NET_INC_STATS_BH(sock_net(sk), LINUX_MIB_DELAYEDACKS);
 	}
-	TCP_CHECK_TIMER(sk);
 
 out:
 	if (tcp_memory_pressure)
@@ -481,7 +480,6 @@ static void tcp_write_timer(unsigned long data)
 		tcp_probe_timer(sk);
 		break;
 	}
-	TCP_CHECK_TIMER(sk);
 
 out:
 	sk_mem_reclaim(sk);
@@ -589,7 +587,6 @@ static void tcp_keepalive_timer (unsigned long data)
 		elapsed = keepalive_time_when(tp) - elapsed;
 	}
 
-	TCP_CHECK_TIMER(sk);
 	sk_mem_reclaim(sk);
 
 resched:

net/ipv6/tcp_ipv6.c

@@ -1636,10 +1636,8 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
 		opt_skb = skb_clone(skb, GFP_ATOMIC);
 
 	if (sk->sk_state == TCP_ESTABLISHED) { /* Fast path */
-		TCP_CHECK_TIMER(sk);
 		if (tcp_rcv_established(sk, skb, tcp_hdr(skb), skb->len))
 			goto reset;
-		TCP_CHECK_TIMER(sk);
 		if (opt_skb)
 			goto ipv6_pktoptions;
 		return 0;
@@ -1667,10 +1665,8 @@ static int tcp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
 		}
 	}
 
-	TCP_CHECK_TIMER(sk);
 	if (tcp_rcv_state_process(sk, skb, tcp_hdr(skb), skb->len))
 		goto reset;
-	TCP_CHECK_TIMER(sk);
 	if (opt_skb)
 		goto ipv6_pktoptions;
 	return 0;