From 57034e740759febe61830aa21cffd7a733dd2b3c Mon Sep 17 00:00:00 2001
From: Garrett Wollman <wollman@FreeBSD.org>
Date: Mon, 8 Aug 1994 15:41:08 +0000
Subject: [PATCH] Run-time configuration of VFS update interval.  Old
 UPDATE_INTERVAL configuration option is no longer supported.

---
 sys/kern/kern_sysctl.c | 16 +++++++++++++++-
 sys/kern/vfs_bio.c     |  6 +-----
 sys/sys/sysctl.h       |  6 ++++--
 3 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/sys/kern/kern_sysctl.c b/sys/kern/kern_sysctl.c
index c1308cdd1315..d9cd27c9e80e 100644
--- a/sys/kern/kern_sysctl.c
+++ b/sys/kern/kern_sysctl.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_sysctl.c	8.4 (Berkeley) 4/14/94
- * $Id: kern_sysctl.c,v 1.3 1994/08/02 07:42:19 davidg Exp $
+ * $Id: kern_sysctl.c,v 1.4 1994/08/08 00:30:03 wollman Exp $
  */
 
 /*
@@ -180,6 +180,8 @@ char domainname[MAXHOSTNAMELEN];
 int domainnamelen;
 long hostid;
 int securelevel;
+extern int vfs_update_wakeup;
+extern int vfs_update_interval;
 
 /*
  * kernel related system variables.
@@ -216,6 +218,18 @@ kern_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
 		return (sysctl_int(oldp, oldlenp, newp, newlen, &maxproc));
 	case KERN_MAXFILES:
 		return (sysctl_int(oldp, oldlenp, newp, newlen, &maxfiles));
+	case KERN_UPDATEINTERVAL:
+		/*
+		 * NB: this simple-minded approach only works because
+		 * `tsleep' takes a timeout argument of 0 as meaning
+		 * `no timeout'.
+		 */
+		error = sysctl_int(oldp, oldlenp, newp, newlen, 
+				   &vfs_update_interval);
+		if(!error) {
+			wakeup(&vfs_update_wakeup);
+		}
+		return error;
 	case KERN_ARGMAX:
 		return (sysctl_rdint(oldp, oldlenp, newp, ARG_MAX));
 	case KERN_SECURELVL:
diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c
index 61a347612e1c..810e28d1371e 100644
--- a/sys/kern/vfs_bio.c
+++ b/sys/kern/vfs_bio.c
@@ -16,7 +16,7 @@
  * 4. Modifications may be freely made to this file if the above conditions
  *    are met.
  *
- * $Id: vfs_bio.c,v 1.6 1994/08/06 09:15:28 davidg Exp $
+ * $Id: vfs_bio.c,v 1.7 1994/08/07 14:53:20 davidg Exp $
  */
 
 #include <sys/param.h>
@@ -646,11 +646,7 @@ count_lock_queue()
 	return(count);
 }
 
-#ifndef UPDATE_INTERVAL
 int vfs_update_interval = 30;
-#else
-int vfs_update_interval = UPDATE_INTERVAL;
-#endif
 
 void
 vfs_update() {
diff --git a/sys/sys/sysctl.h b/sys/sys/sysctl.h
index e4e40bd48a45..590e579369f5 100644
--- a/sys/sys/sysctl.h
+++ b/sys/sys/sysctl.h
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)sysctl.h	8.1 (Berkeley) 6/2/93
- * $Id: sysctl.h,v 1.2 1994/08/02 07:53:41 davidg Exp $
+ * $Id: sysctl.h,v 1.3 1994/08/08 00:30:12 wollman Exp $
  */
 
 #ifndef _SYS_SYSCTL_H_
@@ -129,7 +129,8 @@ struct ctlname {
 #define	KERN_SAVED_IDS		20	/* int: saved set-user/group-ID */
 #define	KERN_BOOTTIME		21	/* struct: time kernel was booted */
 #define KERN_DOMAINNAME		22	/* string: YP domain name */
-#define	KERN_MAXID		23	/* number of valid kern ids */
+#define KERN_UPDATEINTERVAL	23	/* int: update process sleep time */
+#define	KERN_MAXID		24	/* number of valid kern ids */
 
 #define CTL_KERN_NAMES { \
 	{ 0, 0 }, \
@@ -155,6 +156,7 @@ struct ctlname {
 	{ "saved_ids", CTLTYPE_INT }, \
 	{ "boottime", CTLTYPE_STRUCT }, \
 	{ "domainname", CTLTYPE_STRING }, \
+	{ "update", CTLTYPE_INT }, \
 }
 
 /*