From fb8d5c6dd08d24fd5b9446fcab778124489e30b8 Mon Sep 17 00:00:00 2001
From: Sepherosa Ziehau <sephe@dragonflybsd.org>
Date: Thu, 19 Apr 2012 15:16:39 +0800
Subject: [PATCH] tcp: Reimplement TCP_FASTKEEP socket option using per-pcb
 keepidle

Retired now used TF_FASTKEEP
---
 sys/netinet/tcp_input.c  |    4 ++--
 sys/netinet/tcp_timer.c  |   10 +++-------
 sys/netinet/tcp_timer2.h |   13 -------------
 sys/netinet/tcp_usrreq.c |   13 +++++--------
 sys/netinet/tcp_var.h    |    2 +-
 5 files changed, 11 insertions(+), 31 deletions(-)

diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c
index 84b20bf..d6773cc 100644
--- a/sys/netinet/tcp_input.c
+++ b/sys/netinet/tcp_input.c
@@ -3167,7 +3167,7 @@ tcp_timer_keep_activity(struct tcpcb *tp, int thflags)
 			tp->t_rcvtime = ticks;
 			tp->t_flags &= ~TF_KEEPALIVE;
 			tcp_callout_reset(tp, tp->tt_keep,
-					  tcp_getkeepidle(tp),
+					  tp->t_keepidle,
 					  tcp_timer_keep);
 		}
 	}
@@ -3203,7 +3203,7 @@ static void
 tcp_established(struct tcpcb *tp)
 {
 	tp->t_state = TCPS_ESTABLISHED;
-	tcp_callout_reset(tp, tp->tt_keep, tcp_getkeepidle(tp), tcp_timer_keep);
+	tcp_callout_reset(tp, tp->tt_keep, tp->t_keepidle, tcp_timer_keep);
 
 	if (tp->t_rxtsyn > 0) {
 		/*
diff --git a/sys/netinet/tcp_timer.c b/sys/netinet/tcp_timer.c
index aecddc9..66180d0 100644
--- a/sys/netinet/tcp_timer.c
+++ b/sys/netinet/tcp_timer.c
@@ -316,13 +316,9 @@ tcp_timer_keep_handler(struct tcpcb *tp)
 {
 	struct tcptemp *t_template;
 #ifdef TCPDEBUG
-	int ostate;
+	int ostate = tp->t_state;
 #endif
-	int keepidle = tcp_getkeepidle(tp);
 
-#ifdef TCPDEBUG
-	ostate = tp->t_state;
-#endif
 	/*
 	 * Keep-alive timer went off; send something
 	 * or drop connection if idle for too long.
@@ -333,7 +329,7 @@ tcp_timer_keep_handler(struct tcpcb *tp)
 	if ((always_keepalive || (tp->t_flags & TF_KEEPALIVE) ||
 	     (tp->t_inpcb->inp_socket->so_options & SO_KEEPALIVE)) &&
 	    tp->t_state <= TCPS_CLOSING) {
-		if ((ticks - tp->t_rcvtime) >= keepidle + tp->t_maxidle)
+		if ((ticks - tp->t_rcvtime) >= tp->t_keepidle + tp->t_maxidle)
 			goto dropit;
 		/*
 		 * Send a packet designed to force a response
@@ -358,7 +354,7 @@ tcp_timer_keep_handler(struct tcpcb *tp)
 		tcp_callout_reset(tp, tp->tt_keep, tp->t_keepintvl,
 				  tcp_timer_keep);
 	} else {
-		tcp_callout_reset(tp, tp->tt_keep, keepidle,
+		tcp_callout_reset(tp, tp->tt_keep, tp->t_keepidle,
 				  tcp_timer_keep);
 	}
 
diff --git a/sys/netinet/tcp_timer2.h b/sys/netinet/tcp_timer2.h
index 1f17080..32abc96 100644
--- a/sys/netinet/tcp_timer2.h
+++ b/sys/netinet/tcp_timer2.h
@@ -64,19 +64,6 @@
 #include <netinet/tcp_timer.h>
 #endif
 
-/*
- * The TCP_FASTKEEP option uses keepintvl for the initial keepidle timeout
- * instead of keepidle.
- */
-static __inline int
-tcp_getkeepidle(struct tcpcb *_tp)
-{
-	if (_tp->t_flags & TF_FASTKEEP)
-		return (_tp->t_keepintvl);
-	else
-		return (_tp->t_keepidle);
-}
-
 static __inline void
 tcp_callout_stop(struct tcpcb *_tp, struct tcp_callout *_tc)
 {
diff --git a/sys/netinet/tcp_usrreq.c b/sys/netinet/tcp_usrreq.c
index 1b3eb0c..74ca197 100644
--- a/sys/netinet/tcp_usrreq.c
+++ b/sys/netinet/tcp_usrreq.c
@@ -1342,14 +1342,11 @@ tcp_ctloutput(netmsg_t msg)
 			break;
 		switch (sopt->sopt_name) {
 		case TCP_FASTKEEP:
-			if (optval > 0) {
-				if ((tp->t_flags & TF_FASTKEEP) == 0) {
-					tp->t_flags |= TF_FASTKEEP;
-					tcp_timer_keep_activity(tp, 0);
-				}
-			} else {
-				tp->t_flags &= ~TF_FASTKEEP;
-			}
+			if (optval > 0)
+				tp->t_keepidle = tp->t_keepintvl;
+			else
+				tp->t_keepidle = tcp_keepidle;
+			tcp_timer_keep_activity(tp, 0);
 			break;
 #ifdef TCP_SIGNATURE
 		case TCP_SIGNATURE_ENABLE:
diff --git a/sys/netinet/tcp_var.h b/sys/netinet/tcp_var.h
index f041c1f..523ddfc 100644
--- a/sys/netinet/tcp_var.h
+++ b/sys/netinet/tcp_var.h
@@ -162,7 +162,7 @@ struct tcpcb {
 #define	TF_NOPUSH	0x00001000	/* don't push */
 #define TF_LISTEN	0x00002000	/* listen(2) has been called */
 #define TF_SIGNATURE	0x00004000	/* require MD5 digests (RFC2385) */
-#define TF_FASTKEEP	0x00008000	/* use a faster tcp_keepidle */
+#define TF_UNUSED01	0x00008000	/* unused */
 #define	TF_MORETOCOME	0x00010000	/* More data to be appended to sock */
 #define	TF_UNUSED00	0x00020000	/* unused */
 #define	TF_LASTIDLE	0x00040000	/* connection was previously idle */
-- 
1.7.7.2