Back out tcp_timer.c:1.93 and associated changes that reimplemented the many

TCP timers as a single timer, but retain the API changes necessary to
reintroduce this change.  This will back out the source of at least two
reported problems: lock leaks in certain timer edge cases, and TCP timers
continuing to fire after a connection has closed (a bug previously fixed and
then reintroduced with the timer rewrite).

In a follow-up commit, some minor restylings and comment changes performed
after the TCP timer rewrite will be reapplied, and a further change to allow
the TCP timer rewrite to be added back without disturbing the ABI.  The new
design is believed to be a good thing, but the outstanding issues are
leading to significant stability/correctness problems that are holding
up 7.0.

This patch was generated by silby, but is being committed by proxy due to
poor network connectivity for silby this week.

Approved by:	re (kensmith)
Submitted by:	silby
Tested by:	rwatson, kris
Problems reported by:	peter, kris, others

1 files changed, 5 insertions, 10 deletions

diff --git a/sys/netinet/tcp_timer.h b/sys/netinet/tcp_timer.h
index f4392dd16336..83b495842ab3 100644
--- a/sys/netinet/tcp_timer.h
+++ b/sys/netinet/tcp_timer.h
@@ -141,21 +141,11 @@ static const char *tcptimers[] =
 
 #ifdef _KERNEL
 
-struct tcp_timer {
-	struct callout	tt_timer;
-	int		tt_nextc;	/* next callout time in time_uptime */
-	int		tt_active;	/* engaged callouts */
 #define TT_DELACK	0x01
 #define TT_REXMT	0x02
 #define TT_PERSIST	0x04
 #define TT_KEEP		0x08
 #define TT_2MSL		0x10
-	int             tt_delack;
-	int             tt_rexmt;
-	int             tt_persist;
-	int             tt_keep;
-	int             tt_2msl;
-};
 
 extern int tcp_keepinit;		/* time to establish connection */
 extern int tcp_keepidle;		/* time before keepalive probes begin */
@@ -173,8 +163,13 @@ extern int tcp_finwait2_timeout;
 extern int tcp_fast_finwait2_recycle;
 
 void	tcp_timer_init(void);
+void	tcp_timer_2msl(void *xtp);
 struct tcptw *
 	tcp_tw_2msl_scan(int _reuse);		/* XXX temporary */
+void	tcp_timer_keep(void *xtp);
+void	tcp_timer_persist(void *xtp);
+void	tcp_timer_rexmt(void *xtp);
+void	tcp_timer_delack(void *xtp);
 
 #endif /* _KERNEL */