tcp: Namespace-ify sysctl_tcp_thin_linear_timeouts

Note that sysctl_tcp_thin_dupack was not used, I deleted it.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_timer.c b/net/ipv4/tcp_timer.c
index 804a8d3..035a1ef 100644
--- a/net/ipv4/tcp_timer.c
+++ b/net/ipv4/tcp_timer.c
@@ -22,8 +22,6 @@
 #include <linux/gfp.h>
 #include <net/tcp.h>
 
-int sysctl_tcp_thin_linear_timeouts __read_mostly;
-
 /**
  *  tcp_write_err() - close socket and save error info
  *  @sk:  The socket the error has appeared on.
@@ -522,7 +520,7 @@ void tcp_retransmit_timer(struct sock *sk)
 	 * linear-timeout retransmissions into a black hole
 	 */
 	if (sk->sk_state == TCP_ESTABLISHED &&
-	    (tp->thin_lto || sysctl_tcp_thin_linear_timeouts) &&
+	    (tp->thin_lto || net->ipv4.sysctl_tcp_thin_linear_timeouts) &&
 	    tcp_stream_is_thin(tp) &&
 	    icsk->icsk_retransmits <= TCP_THIN_LINEAR_RETRIES) {
 		icsk->icsk_backoff = 0;