WLAN subsystem: Sysctl support for key TCP/IP parameters

It has been observed that default values for some of key tcp/ip
parameters are affecting the tput/performance of the system. Hence
extending configuration capabilities to TCP/Ip stack through
sysctl interface.

Change-Id: I0c99d5b50cbe0d6496e40d391eacc12b0c62dbed
CRs-Fixed: 507581
Signed-off-by: Mahesh A Saptasagar <msapta@codeaurora.org>
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 257b617..7c3612b 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -5047,7 +5047,8 @@
 	struct tcp_sock *tp = tcp_sk(sk);
 
 	    /* More than one full frame received... */
-	if (((tp->rcv_nxt - tp->rcv_wup) > inet_csk(sk)->icsk_ack.rcv_mss &&
+	if (((tp->rcv_nxt - tp->rcv_wup) > (inet_csk(sk)->icsk_ack.rcv_mss) *
+					sysctl_tcp_delack_seg &&
 	     /* ... and right edge of window advances far enough.
 	      * (tcp_recvmsg() will send ACK otherwise). Or...
 	      */