diff --git a/sys/coda/coda_vnops.c b/sys/coda/coda_vnops.c
index b401cd346744..c0cfa5e00f92 100644
--- a/sys/coda/coda_vnops.c
+++ b/sys/coda/coda_vnops.c
@@ -27,7 +27,7 @@
  * Mellon the rights to redistribute these changes without encumbrance.
  * 
  *  	@(#) src/sys/coda/coda_vnops.c,v 1.1.1.1 1998/08/29 21:14:52 rvb Exp $
- *  $Id: coda_vnops.c,v 1.11 1999/01/05 18:49:51 eivind Exp $
+ *  $Id: coda_vnops.c,v 1.12 1999/01/07 16:14:12 bde Exp $
  * 
  */
 
@@ -48,6 +48,11 @@
 /*
  * HISTORY
  * $Log: coda_vnops.c,v $
+ * Revision 1.12  1999/01/07 16:14:12  bde
+ * Don't pass unused unused timestamp args to UFS_UPDATE() or waste
+ * time initializing them.  This almost finishes centralizing (in-core)
+ * timestamp updates in ufs_itimes().
+ *
  * Revision 1.11  1999/01/05 18:49:51  eivind
  * Remove the 'waslocked' parameter to vfs_object_create().
  *
@@ -2037,7 +2042,12 @@ coda_lock(v)
 		  cp->c_fid.Volume, cp->c_fid.Vnode, cp->c_fid.Unique));
     }
 
+#ifndef	DEBUG_LOCKS
     return (lockmgr(&cp->c_lock, ap->a_flags, &vp->v_interlock, p));
+#else
+    return (debuglockmgr(&cp->c_lock, ap->a_flags, &vp->v_interlock, p,
+			 "coda_lock", vp->filename, vp->line));
+#endif
 }
 
 int
diff --git a/sys/conf/NOTES b/sys/conf/NOTES
index e151c090da04..762e124d525a 100644
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -2,7 +2,7 @@
 # LINT -- config file for checking all the sources, tries to pull in
 #	as much of the source tree as it can.
 #
-#	$Id: LINT,v 1.537 1999/01/19 15:11:46 des Exp $
+#	$Id: LINT,v 1.538 1999/01/20 03:29:51 msmith Exp $
 #
 # NB: You probably don't want to try running a kernel built from this
 # file.  Instead, you should start from GENERIC, and add options from
@@ -1844,6 +1844,14 @@ options         "PMAP_SHPGPERPROC=201"
 #
 options		"NSFBUFS=1024"
 
+#
+# Enable extra debugging code for locks.  This include storing the
+# filename and line of whatever aquired the lock in the lock itself,
+# and changing a number of function calls to pass around the relevant
+# data.  This is not at all useful unless you are debugging lock code.
+#
+options		DEBUG_LOCKS
+
 # More undocumented options for linting.
 
 options		CLK_CALIBRATION_LOOP
@@ -1853,6 +1861,7 @@ options		CLUSTERDEBUG
 options		COMPAT_LINUX
 options		CPU_UPGRADE_HW_CACHE
 options		DEBUG
+options		DEBUG_VFS_LOCKS
 options		"DEBUG_1284"
 #options	DISABLE_PSE
 options		"EXT2FS"
diff --git a/sys/conf/options b/sys/conf/options
index 6089840cf00b..35ceb1a53ffa 100644
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -1,4 +1,4 @@
-#	$Id: options,v 1.119 1999/01/15 10:00:10 bde Exp $
+#	$Id: options,v 1.120 1999/01/17 19:02:39 peter Exp $
 #
 #        On the handling of kernel options   
 # 
@@ -255,6 +255,7 @@ SI_DEBUG		opt_debug_si.h
 
 # These cause changes all over the kernel
 DEBUG			opt_global.h
+DEBUG_LOCKS		opt_global.h
 DEBUG_VFS_LOCKS		opt_global.h
 DIAGNOSTIC		opt_global.h
 ENABLE_VFS_IOOPT	opt_global.h
diff --git a/sys/fs/coda/coda_vnops.c b/sys/fs/coda/coda_vnops.c
index b401cd346744..c0cfa5e00f92 100644
--- a/sys/fs/coda/coda_vnops.c
+++ b/sys/fs/coda/coda_vnops.c
@@ -27,7 +27,7 @@
  * Mellon the rights to redistribute these changes without encumbrance.
  * 
  *  	@(#) src/sys/coda/coda_vnops.c,v 1.1.1.1 1998/08/29 21:14:52 rvb Exp $
- *  $Id: coda_vnops.c,v 1.11 1999/01/05 18:49:51 eivind Exp $
+ *  $Id: coda_vnops.c,v 1.12 1999/01/07 16:14:12 bde Exp $
  * 
  */
 
@@ -48,6 +48,11 @@
 /*
  * HISTORY
  * $Log: coda_vnops.c,v $
+ * Revision 1.12  1999/01/07 16:14:12  bde
+ * Don't pass unused unused timestamp args to UFS_UPDATE() or waste
+ * time initializing them.  This almost finishes centralizing (in-core)
+ * timestamp updates in ufs_itimes().
+ *
  * Revision 1.11  1999/01/05 18:49:51  eivind
  * Remove the 'waslocked' parameter to vfs_object_create().
  *
@@ -2037,7 +2042,12 @@ coda_lock(v)
 		  cp->c_fid.Volume, cp->c_fid.Vnode, cp->c_fid.Unique));
     }
 
+#ifndef	DEBUG_LOCKS
     return (lockmgr(&cp->c_lock, ap->a_flags, &vp->v_interlock, p));
+#else
+    return (debuglockmgr(&cp->c_lock, ap->a_flags, &vp->v_interlock, p,
+			 "coda_lock", vp->filename, vp->line));
+#endif
 }
 
 int
diff --git a/sys/i386/conf/LINT b/sys/i386/conf/LINT
index e151c090da04..762e124d525a 100644
--- a/sys/i386/conf/LINT
+++ b/sys/i386/conf/LINT
@@ -2,7 +2,7 @@
 # LINT -- config file for checking all the sources, tries to pull in
 #	as much of the source tree as it can.
 #
-#	$Id: LINT,v 1.537 1999/01/19 15:11:46 des Exp $
+#	$Id: LINT,v 1.538 1999/01/20 03:29:51 msmith Exp $
 #
 # NB: You probably don't want to try running a kernel built from this
 # file.  Instead, you should start from GENERIC, and add options from
@@ -1844,6 +1844,14 @@ options         "PMAP_SHPGPERPROC=201"
 #
 options		"NSFBUFS=1024"
 
+#
+# Enable extra debugging code for locks.  This include storing the
+# filename and line of whatever aquired the lock in the lock itself,
+# and changing a number of function calls to pass around the relevant
+# data.  This is not at all useful unless you are debugging lock code.
+#
+options		DEBUG_LOCKS
+
 # More undocumented options for linting.
 
 options		CLK_CALIBRATION_LOOP
@@ -1853,6 +1861,7 @@ options		CLUSTERDEBUG
 options		COMPAT_LINUX
 options		CPU_UPGRADE_HW_CACHE
 options		DEBUG
+options		DEBUG_VFS_LOCKS
 options		"DEBUG_1284"
 #options	DISABLE_PSE
 options		"EXT2FS"
diff --git a/sys/i386/conf/NOTES b/sys/i386/conf/NOTES
index e151c090da04..762e124d525a 100644
--- a/sys/i386/conf/NOTES
+++ b/sys/i386/conf/NOTES
@@ -2,7 +2,7 @@
 # LINT -- config file for checking all the sources, tries to pull in
 #	as much of the source tree as it can.
 #
-#	$Id: LINT,v 1.537 1999/01/19 15:11:46 des Exp $
+#	$Id: LINT,v 1.538 1999/01/20 03:29:51 msmith Exp $
 #
 # NB: You probably don't want to try running a kernel built from this
 # file.  Instead, you should start from GENERIC, and add options from
@@ -1844,6 +1844,14 @@ options         "PMAP_SHPGPERPROC=201"
 #
 options		"NSFBUFS=1024"
 
+#
+# Enable extra debugging code for locks.  This include storing the
+# filename and line of whatever aquired the lock in the lock itself,
+# and changing a number of function calls to pass around the relevant
+# data.  This is not at all useful unless you are debugging lock code.
+#
+options		DEBUG_LOCKS
+
 # More undocumented options for linting.
 
 options		CLK_CALIBRATION_LOOP
@@ -1853,6 +1861,7 @@ options		CLUSTERDEBUG
 options		COMPAT_LINUX
 options		CPU_UPGRADE_HW_CACHE
 options		DEBUG
+options		DEBUG_VFS_LOCKS
 options		"DEBUG_1284"
 #options	DISABLE_PSE
 options		"EXT2FS"
diff --git a/sys/kern/kern_lock.c b/sys/kern/kern_lock.c
index 0903f6e1e035..e832acff84a2 100644
--- a/sys/kern/kern_lock.c
+++ b/sys/kern/kern_lock.c
@@ -38,7 +38,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)kern_lock.c	8.18 (Berkeley) 5/21/95
- * $Id: kern_lock.c,v 1.21 1999/01/08 17:31:08 eivind Exp $
+ * $Id: kern_lock.c,v 1.22 1999/01/10 01:58:24 eivind Exp $
  */
 
 #include "opt_lint.h"
@@ -171,11 +171,20 @@ acquire(struct lock *lkp, int extflags, int wanted) {
  * accepted shared locks and shared-to-exclusive upgrades to go away.
  */
 int
+#ifndef	DEBUG_LOCKS
 lockmgr(lkp, flags, interlkp, p)
+#else
+debuglockmgr(lkp, flags, interlkp, p, name, file, line)
+#endif
 	struct lock *lkp;
 	u_int flags;
 	struct simplelock *interlkp;
 	struct proc *p;
+#ifdef	DEBUG_LOCKS
+	const char *name;	/* Name of lock function */
+	const char *file;	/* Name of file call is from */
+	int line;		/* Line number in file */
+#endif
 {
 	int error;
 	pid_t pid;
@@ -283,6 +292,11 @@ lockmgr(lkp, flags, interlkp, p)
 				panic("lockmgr: non-zero exclusive count");
 #endif
 			lkp->lk_exclusivecount = 1;
+#if defined(DEBUG_LOCKS)
+			lkp->lk_filename = file;
+			lkp->lk_lineno = line;
+			lkp->lk_lockername = name;
+#endif
 			COUNT(p, 1);
 			break;
 		}
@@ -338,6 +352,11 @@ lockmgr(lkp, flags, interlkp, p)
 			panic("lockmgr: non-zero exclusive count");
 #endif
 		lkp->lk_exclusivecount = 1;
+#if defined(DEBUG_LOCKS)
+			lkp->lk_filename = file;
+			lkp->lk_lineno = line;
+			lkp->lk_lockername = name;
+#endif
 		COUNT(p, 1);
 		break;
 
@@ -383,6 +402,11 @@ lockmgr(lkp, flags, interlkp, p)
 		lkp->lk_flags |= LK_DRAINING | LK_HAVE_EXCL;
 		lkp->lk_lockholder = pid;
 		lkp->lk_exclusivecount = 1;
+#if defined(DEBUG_LOCKS)
+			lkp->lk_filename = file;
+			lkp->lk_lineno = line;
+			lkp->lk_lockername = name;
+#endif
 		COUNT(p, 1);
 		break;
 
diff --git a/sys/kern/vfs_default.c b/sys/kern/vfs_default.c
index 47545c3b87c8..b73b126a82cc 100644
--- a/sys/kern/vfs_default.c
+++ b/sys/kern/vfs_default.c
@@ -205,7 +205,12 @@ vop_stdlock(ap)
 		return 0;
 	}
 
+#ifndef	DEBUG_LOCKS
 	return (lockmgr(l, ap->a_flags, &ap->a_vp->v_interlock, ap->a_p));
+#else
+	return (debuglockmgr(l, ap->a_flags, &ap->a_vp->v_interlock, ap->a_p,
+	    "vop_stdlock", ap->a_vp->filename, ap->a_vp->line));
+#endif
 }
 
 int
@@ -355,7 +360,12 @@ vop_sharedlock(ap)
 	}
 	if (flags & LK_INTERLOCK)
 		vnflags |= LK_INTERLOCK;
-	return(lockmgr(vp->v_vnlock, vnflags, &vp->v_interlock, ap->a_p));
+#ifndef	DEBUG_LOCKS
+	return (lockmgr(vp->v_vnlock, vnflags, &vp->v_interlock, ap->a_p));
+#else
+	return (debuglockmgr(vp->v_vnlock, vnflags, &vp->v_interlock, ap->a_p,
+	    "vop_sharedlock", vp->filename, vp->line));
+#endif
 }
 
 /*
diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
index 756c94555d34..0b32a7d1950c 100644
--- a/sys/kern/vfs_vnops.c
+++ b/sys/kern/vfs_vnops.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_vnops.c	8.2 (Berkeley) 1/21/94
- * $Id: vfs_vnops.c,v 1.60 1998/11/02 02:36:16 peter Exp $
+ * $Id: vfs_vnops.c,v 1.61 1999/01/05 18:49:56 eivind Exp $
  */
 
 #include <sys/param.h>
@@ -510,10 +510,18 @@ vn_poll(fp, events, cred, p)
  * acquire requested lock.
  */
 int
+#ifndef	DEBUG_LOCKS
 vn_lock(vp, flags, p)
+#else
+debug_vn_lock(vp, flags, p, filename, line)
+#endif
 	struct vnode *vp;
 	int flags;
 	struct proc *p;
+#ifdef	DEBUG_LOCKS
+	const char *filename;
+	int line;
+#endif
 {
 	int error;
 	
@@ -526,7 +534,12 @@ vn_lock(vp, flags, p)
 			tsleep((caddr_t)vp, PINOD, "vn_lock", 0);
 			error = ENOENT;
 		} else {
-			error = VOP_LOCK(vp, flags | LK_NOPAUSE | LK_INTERLOCK, p);
+#ifdef	DEBUG_LOCKS
+			vp->filename = filename;
+			vp->line = line;
+#endif
+			error = VOP_LOCK(vp,
+				    flags | LK_NOPAUSE | LK_INTERLOCK, p);
 			if (error == 0)
 				return (error);
 		}
diff --git a/sys/sys/lock.h b/sys/sys/lock.h
index 592a705afa6e..c9c287d120c6 100644
--- a/sys/sys/lock.h
+++ b/sys/sys/lock.h
@@ -35,7 +35,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)lock.h	8.12 (Berkeley) 5/19/95
- * $Id: lock.h,v 1.11 1998/01/06 05:22:48 dyson Exp $
+ * $Id: lock.h,v 1.12 1999/01/02 11:34:56 bde Exp $
  */
 
 #ifndef	_LOCK_H_
@@ -59,6 +59,11 @@ struct lock {
 	char	*lk_wmesg;		/* resource sleeping (for tsleep) */
 	int	lk_timo;		/* maximum sleep time (for tsleep) */
 	pid_t	lk_lockholder;		/* pid of exclusive lock holder */
+#ifdef	DEBUG_LOCKS
+	const char *lk_filename;
+	const char *lk_lockername;
+	int     lk_lineno;
+#endif
 };
 /*
  * Lock request types:
@@ -169,8 +174,19 @@ struct proc;
 
 void	lockinit __P((struct lock *, int prio, char *wmesg, int timo,
 			int flags));
+#ifdef DEBUG_LOCKS
+int	debuglockmgr __P((struct lock *, u_int flags,
+			struct simplelock *, struct proc *p,
+			const char *,
+			const char *,
+			int));
+#define lockmgr(lockp, flags, slockp, proc) \
+	debuglockmgr((lockp), (flags), (slockp), (proc), \
+	    "lockmgr", __FILE__, __LINE__)
+#else
 int	lockmgr __P((struct lock *, u_int flags,
 			struct simplelock *, struct proc *p));
+#endif
 void	lockmgr_printinfo __P((struct lock *));
 int	lockstatus __P((struct lock *));
 
diff --git a/sys/sys/lockmgr.h b/sys/sys/lockmgr.h
index 592a705afa6e..c9c287d120c6 100644
--- a/sys/sys/lockmgr.h
+++ b/sys/sys/lockmgr.h
@@ -35,7 +35,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)lock.h	8.12 (Berkeley) 5/19/95
- * $Id: lock.h,v 1.11 1998/01/06 05:22:48 dyson Exp $
+ * $Id: lock.h,v 1.12 1999/01/02 11:34:56 bde Exp $
  */
 
 #ifndef	_LOCK_H_
@@ -59,6 +59,11 @@ struct lock {
 	char	*lk_wmesg;		/* resource sleeping (for tsleep) */
 	int	lk_timo;		/* maximum sleep time (for tsleep) */
 	pid_t	lk_lockholder;		/* pid of exclusive lock holder */
+#ifdef	DEBUG_LOCKS
+	const char *lk_filename;
+	const char *lk_lockername;
+	int     lk_lineno;
+#endif
 };
 /*
  * Lock request types:
@@ -169,8 +174,19 @@ struct proc;
 
 void	lockinit __P((struct lock *, int prio, char *wmesg, int timo,
 			int flags));
+#ifdef DEBUG_LOCKS
+int	debuglockmgr __P((struct lock *, u_int flags,
+			struct simplelock *, struct proc *p,
+			const char *,
+			const char *,
+			int));
+#define lockmgr(lockp, flags, slockp, proc) \
+	debuglockmgr((lockp), (flags), (slockp), (proc), \
+	    "lockmgr", __FILE__, __LINE__)
+#else
 int	lockmgr __P((struct lock *, u_int flags,
 			struct simplelock *, struct proc *p));
+#endif
 void	lockmgr_printinfo __P((struct lock *));
 int	lockstatus __P((struct lock *));
 
diff --git a/sys/sys/vnode.h b/sys/sys/vnode.h
index 3df713ef0090..f5c54b11c533 100644
--- a/sys/sys/vnode.h
+++ b/sys/sys/vnode.h
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vnode.h	8.7 (Berkeley) 2/4/94
- * $Id: vnode.h,v 1.78 1998/11/10 09:04:09 peter Exp $
+ * $Id: vnode.h,v 1.79 1999/01/05 18:50:01 eivind Exp $
  */
 
 #ifndef _SYS_VNODE_H_
@@ -125,6 +125,10 @@ struct vnode {
 		short	vpi_events;		/* what they are looking for */
 		short	vpi_revents;		/* what has happened */
 	} v_pollinfo;
+#ifdef	DEBUG_LOCKS
+	const char *filename;			/* Source file doing locking */
+	int line;				/* Line number doing locking */
+#endif
 };
 #define	v_mountedhere	v_un.vu_mountedhere
 #define	v_socket	v_un.vu_socket
@@ -505,6 +509,11 @@ int	vrecycle __P((struct vnode *vp, struct simplelock *inter_lkp,
 int 	vn_close __P((struct vnode *vp,
 	    int flags, struct ucred *cred, struct proc *p));
 int	vn_lock __P((struct vnode *vp, int flags, struct proc *p));
+#ifdef	DEBUG_LOCKS
+int	debug_vn_lock __P((struct vnode *vp, int flags, struct proc *p,
+	    const char *filename, int line));
+#define vn_lock(vp,flags,p) debug_vn_lock(vp,flags,p,__FILE__,__LINE__)
+#endif
 int 	vn_open __P((struct nameidata *ndp, int fmode, int cmode));
 void	vn_pollevent __P((struct vnode *vp, int events));
 void	vn_pollgone __P((struct vnode *vp));