Use a lockmgr lock for keeping down the vslocked memory in sysctl

instead of a home-brew equivalent.

3 files changed, 21 insertions, 20 deletions

diff --git a/sys/kern/init_main.c b/sys/kern/init_main.c
index 919bcf2be12..b309b6f8d8a 100644
--- a/sys/kern/init_main.c
+++ b/sys/kern/init_main.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: init_main.c,v 1.58 2001/02/05 21:28:06 mickey Exp $	*/
+/*	$OpenBSD: init_main.c,v 1.59 2001/03/16 08:49:09 art Exp $	*/
 /*	$NetBSD: init_main.c,v 1.84.4.1 1996/06/02 09:08:06 mrg Exp $	*/
 
 /*
@@ -222,6 +222,9 @@ main(framep)
 	tty_init();		/* initialise tty's */
 	cpu_startup();
 
+	/* Initialize sysctls (must be done before any processes run) */
+	sysctl_init();
+
 	/*
 	 * Initialize process and pgrp structures.
 	 */
diff --git a/sys/kern/kern_sysctl.c b/sys/kern/kern_sysctl.c
index 1a049ad54d0..1af6d28fd50 100644
--- a/sys/kern/kern_sysctl.c
+++ b/sys/kern/kern_sysctl.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_sysctl.c,v 1.38 2001/01/31 09:59:51 deraadt Exp $	*/
+/*	$OpenBSD: kern_sysctl.c,v 1.39 2001/03/16 08:49:09 art Exp $	*/
 /*	$NetBSD: kern_sysctl.c,v 1.17 1996/05/20 17:49:05 mrg Exp $	*/
 
 /*-
@@ -74,13 +74,16 @@
 #endif
 
 /*
- * Locking and stats
+ * Lock to avoid too many processes vslocking a large amount of memory
+ * at the same time.
  */
-static struct sysctl_lock {
-	int	sl_lock;
-	int	sl_want;
-	int	sl_locked;
-} memlock;
+struct lock sysctl_lock;
+
+void
+sysctl_init()
+{
+	lockinit(&sysctl_lock, PLOCK|PCATCH, "sysctl", 0, 0);
+}
 
 int
 sys___sysctl(p, v, retval)
@@ -166,12 +169,8 @@ sys___sysctl(p, v, retval)
 		if (!useracc(SCARG(uap, old), oldlen, B_WRITE))
 #endif
 			return (EFAULT);
-		while (memlock.sl_lock) {
-			memlock.sl_want = 1;
-			sleep((caddr_t)&memlock, PRIBIO+1);
-			memlock.sl_locked++;
-		}
-		memlock.sl_lock = 1;
+		if ((error = lockmgr(&sysctl_lock, LK_EXCLUSIVE, NULL, p)) != 0)
+			return (error);
 		if (dolock)
 #if defined(UVM)
 			uvm_vslock(p, SCARG(uap, old), oldlen, VM_PROT_NONE);
@@ -189,11 +188,7 @@ sys___sysctl(p, v, retval)
 #else
 			vsunlock(SCARG(uap, old), savelen);
 #endif
-		memlock.sl_lock = 0;
-		if (memlock.sl_want) {
-			memlock.sl_want = 0;
-			wakeup((caddr_t)&memlock);
-		}
+		lockmgr(&sysctl_lock, LK_RELEASE, NULL, p);
 	}
 	if (error)
 		return (error);
diff --git a/sys/sys/sysctl.h b/sys/sys/sysctl.h
index a842f83af6c..f68d920ca51 100644
--- a/sys/sys/sysctl.h
+++ b/sys/sys/sysctl.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: sysctl.h,v 1.34 2001/01/31 09:59:50 deraadt Exp $	*/
+/*	$OpenBSD: sysctl.h,v 1.35 2001/03/16 08:49:08 art Exp $	*/
 /*	$NetBSD: sysctl.h,v 1.16 1996/04/09 20:55:36 cgd Exp $	*/
 
 /*
@@ -437,6 +437,9 @@ int cpu_sysctl __P((int *, u_int, void *, size_t *, void *, size_t,
 		    struct proc *));
 int vfs_sysctl __P((int *, u_int, void *, size_t *, void *, size_t,
 		    struct proc *));
+
+void sysctl_init __P((void));
+
 #else	/* !_KERNEL */
 #include <sys/cdefs.h>