Change the 0xdeadb hack to a flag called VDOOMED.

Introduce VFREE which indicates that vnode is on freelist.
Rename vholdrele() to vdrop().
Create vfree() and vbusy() to add/delete vnode from freelist.
Add vfree()/vbusy() to keep (v_holdcnt != 0 || v_usecount != 0)
  vnodes off the freelist.
Generalize vhold()/v_holdcnt to mean "do not recycle".
Fix reassignbuf()s lack of use of vhold().
Use vhold() instead of checking v_cache_src list.
Remove vtouch(), the vnodes are always vget'ed soon enough
  after for it to have any measuable effect.
Add sysctl debug.freevnodes to keep track of things.
Move cache_purge() up in getnewvnodes to avoid race.
Decrement v_usecount after VOP_INACTIVE(), put a vhold() on
  it during VOP_INACTIVE()
Unmacroize vhold()/vdrop()
Print out VDOOMED and VFREE flags (XXX: should use %b)

Reviewed by:		dyson

6 files changed, 163 insertions, 148 deletions

diff --git a/sys/kern/vfs_cache.c b/sys/kern/vfs_cache.c
index a1f94f4..f4f52bb 100644
--- a/sys/kern/vfs_cache.c
+++ b/sys/kern/vfs_cache.c
@@ -34,7 +34,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_cache.c	8.5 (Berkeley) 3/22/95
- * $Id: vfs_cache.c,v 1.26 1997/08/04 07:31:36 phk Exp $
+ * $Id: vfs_cache.c,v 1.27 1997/08/26 07:32:34 phk Exp $
  */
 
 #include <sys/param.h>
@@ -103,6 +103,8 @@ cache_zap(ncp)
 {
 	LIST_REMOVE(ncp, nc_hash);
 	LIST_REMOVE(ncp, nc_src);
+	if (LIST_EMPTY(&ncp->nc_dvp->v_cache_src)) 
+		vdrop(ncp->nc_dvp);
 	if (ncp->nc_vp) {
 		TAILQ_REMOVE(&ncp->nc_vp->v_cache_dst, ncp, nc_dst);
 	} else {
@@ -180,7 +182,6 @@ cache_lookup(dvp, vpp, cnp)
 	/* We found a "positive" match, return the vnode */
         if (ncp->nc_vp) {
 		nchstats.ncs_goodhits++;
-		vtouch(ncp->nc_vp);
 		*vpp = ncp->nc_vp;
 		return (-1);
 	}
@@ -239,8 +240,10 @@ cache_enter(dvp, vp, cnp)
 		malloc(sizeof *ncp + cnp->cn_namelen, M_CACHE, M_WAITOK);
 	bzero((char *)ncp, sizeof *ncp);
 	numcache++;
-	if (!vp)
+	if (!vp) {
 		numneg++;
+		ncp->nc_flag = cnp->cn_flags & ISWHITEOUT ? NCF_WHITE : 0;
+	}
 
 	/*
 	 * Fill in cache info, if vp is NULL this is a "negative" cache entry.
@@ -249,15 +252,13 @@ cache_enter(dvp, vp, cnp)
 	 * otherwise unused.
 	 */
 	ncp->nc_vp = vp;
-	if (vp)
-		vtouch(vp);
-	else
-		ncp->nc_flag = cnp->cn_flags & ISWHITEOUT ? NCF_WHITE : 0;
 	ncp->nc_dvp = dvp;
 	ncp->nc_nlen = cnp->cn_namelen;
 	bcopy(cnp->cn_nameptr, ncp->nc_name, (unsigned)ncp->nc_nlen);
 	ncpp = NCHHASH(dvp, cnp);
 	LIST_INSERT_HEAD(ncpp, ncp, nc_hash);
+	if (LIST_EMPTY(&dvp->v_cache_src))
+		vhold(dvp);
 	LIST_INSERT_HEAD(&dvp->v_cache_src, ncp, nc_src);
 	if (vp) {
 		TAILQ_INSERT_HEAD(&vp->v_cache_dst, ncp, nc_dst);
diff --git a/sys/kern/vfs_export.c b/sys/kern/vfs_export.c
index 143521c..6358781 100644
--- a/sys/kern/vfs_export.c
+++ b/sys/kern/vfs_export.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_subr.c	8.31 (Berkeley) 5/26/95
- * $Id: vfs_subr.c,v 1.94 1997/08/26 04:36:17 dyson Exp $
+ * $Id: vfs_subr.c,v 1.95 1997/08/26 11:59:20 bde Exp $
  */
 
 /*
@@ -103,6 +103,7 @@ int vttoif_tab[9] = {
 }
 TAILQ_HEAD(freelst, vnode) vnode_free_list;	/* vnode free list */
 static u_long freevnodes = 0;
+SYSCTL_INT(_debug, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, "");
 
 struct mntlist mountlist;	/* mounted filesystem list */
 struct simplelock mountlist_slock;
@@ -380,11 +381,11 @@ getnewvnode(tag, mp, vops, vpp)
 	}
 
 	if (vp) {
+		vp->v_flag |= VDOOMED;
 		TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
 		freevnodes--;
-		/* see comment on why 0xdeadb is set at end of vgone (below) */
-		vp->v_freelist.tqe_prev = (struct vnode **) 0xdeadb;
 		simple_unlock(&vnode_free_list_slock);
+		cache_purge(vp);
 		vp->v_lease = NULL;
 		if (vp->v_type != VBAD)
 			vgonel(vp, p);
@@ -418,13 +419,13 @@ getnewvnode(tag, mp, vops, vpp)
 		    M_VNODE, M_WAITOK);
 		bzero((char *) vp, sizeof *vp);
 		vp->v_dd = vp;
+		cache_purge(vp);
 		LIST_INIT(&vp->v_cache_src);
 		TAILQ_INIT(&vp->v_cache_dst);
 		numvnodes++;
 	}
 
 	vp->v_type = VNON;
-	cache_purge(vp);
 	vp->v_tag = tag;
 	vp->v_op = vops;
 	insmntque(vp, mp);
@@ -582,7 +583,7 @@ bgetvp(vp, bp)
 
 	if (bp->b_vp)
 		panic("bgetvp: not free");
-	VHOLD(vp);
+	vhold(vp);
 	bp->b_vp = vp;
 	if (vp->v_type == VBLK || vp->v_type == VCHR)
 		bp->b_dev = vp->v_rdev;
@@ -618,7 +619,7 @@ brelvp(bp)
 
 	vp = bp->b_vp;
 	bp->b_vp = (struct vnode *) 0;
-	HOLDRELE(vp);
+	vdrop(vp);
 }
 
 /*
@@ -678,8 +679,10 @@ reassignbuf(bp, newvp)
 	/*
 	 * Delete from old vnode list, if on one.
 	 */
-	if (bp->b_vnbufs.le_next != NOLIST)
+	if (bp->b_vnbufs.le_next != NOLIST) {
 		bufremvn(bp);
+		vdrop(bp->b_vp);
+	}
 	/*
 	 * If dirty, put on list of dirty buffers; otherwise insert onto list
 	 * of clean buffers.
@@ -700,6 +703,8 @@ reassignbuf(bp, newvp)
 	} else {
 		bufinsvn(bp, &newvp->v_cleanblkhd);
 	}
+	bp->b_vp = newvp;
+	vhold(bp->b_vp);
 	splx(s);
 }
 
@@ -836,13 +841,9 @@ vget(vp, flags, p)
 		tsleep((caddr_t)vp, PINOD, "vget", 0);
 		return (ENOENT);
 	}
-	if (vp->v_usecount == 0) {
-		simple_lock(&vnode_free_list_slock);
-		TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
-		simple_unlock(&vnode_free_list_slock);
-		freevnodes--;
-	}
 	vp->v_usecount++;
+	if (VSHOULDBUSY(vp))
+		vbusy(vp);
 	/*
 	 * Create the VM object, if needed
 	 */
@@ -1089,11 +1090,11 @@ vputrele(vp, put)
 		panic("vputrele: null vp");
 #endif
 	simple_lock(&vp->v_interlock);
-	vp->v_usecount--;
 
-	if ((vp->v_usecount == 1) &&
+	if ((vp->v_usecount == 2) &&
 		vp->v_object &&
 		(vp->v_object->flags & OBJ_VFS_REF)) {
+		vp->v_usecount--;
 		vp->v_object->flags &= ~OBJ_VFS_REF;
 		if (put) {
 			VOP_UNLOCK(vp, LK_INTERLOCK, p);
@@ -1104,7 +1105,8 @@ vputrele(vp, put)
 		return;
 	}
 
-	if (vp->v_usecount > 0) {
+	if (vp->v_usecount > 1) {
+		vp->v_usecount--;
 		if (put) {
 			VOP_UNLOCK(vp, LK_INTERLOCK, p);
 		} else {
@@ -1113,23 +1115,14 @@ vputrele(vp, put)
 		return;
 	}
 
-	if (vp->v_usecount < 0) {
+	if (vp->v_usecount < 1) {
 #ifdef DIAGNOSTIC
 		vprint("vputrele: negative ref count", vp);
 #endif
 		panic("vputrele: negative ref cnt");
 	}
-	simple_lock(&vnode_free_list_slock);
-	if (vp->v_flag & VAGE) {
-		vp->v_flag &= ~VAGE;
-		if(vp->v_tag != VT_TFS)
-			TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
-	} else {
-		if(vp->v_tag != VT_TFS)
-			TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
-	}
-	freevnodes++;
-	simple_unlock(&vnode_free_list_slock);
+
+	vp->v_holdcnt++; 	/* Make sure vnode isn't recycled */
 
 	/*
 	 * If we are doing a vput, the node is already locked, and we must
@@ -1139,8 +1132,18 @@ vputrele(vp, put)
 	if (put) {
 		simple_unlock(&vp->v_interlock);
 		VOP_INACTIVE(vp, p);
+		simple_lock(&vp->v_interlock);
+		vp->v_usecount--;
+		vp->v_holdcnt--;
+		if (VSHOULDFREE(vp))
+			vfree(vp);
+		simple_unlock(&vp->v_interlock);
 	} else if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK, p) == 0) {
 		VOP_INACTIVE(vp, p);
+		vp->v_usecount--;
+		vp->v_holdcnt--;
+		if (VSHOULDFREE(vp))
+			vfree(vp);
 	}
 }
 
@@ -1161,9 +1164,8 @@ vrele(vp)
 	vputrele(vp, 0);
 }
 
-#ifdef DIAGNOSTIC
 /*
- * Page or buffer structure gets a reference.
+ * Somebody doesn't want the vnode recycled.
  */
 void
 vhold(vp)
@@ -1172,14 +1174,16 @@ vhold(vp)
 
 	simple_lock(&vp->v_interlock);
 	vp->v_holdcnt++;
+	if (VSHOULDBUSY(vp))
+		vbusy(vp);
 	simple_unlock(&vp->v_interlock);
 }
 
 /*
- * Page or buffer structure frees a reference.
+ * One less who cares about this vnode.
  */
 void
-holdrele(vp)
+vdrop(vp)
 	register struct vnode *vp;
 {
 
@@ -1187,9 +1191,10 @@ holdrele(vp)
 	if (vp->v_holdcnt <= 0)
 		panic("holdrele: holdcnt");
 	vp->v_holdcnt--;
+	if (VSHOULDFREE(vp))
+		vfree(vp);
 	simple_unlock(&vp->v_interlock);
 }
-#endif /* DIAGNOSTIC */
 
 /*
  * Remove any vnodes in the vnode table belonging to mount point mp.
@@ -1572,17 +1577,11 @@ vgonel(vp, p)
 	 * after calling vgone. If the reference count were
 	 * incremented first, vgone would (incorrectly) try to
 	 * close the previous instance of the underlying object.
-	 * So, the back pointer is explicitly set to `0xdeadb' in
-	 * getnewvnode after removing it from the freelist to ensure
-	 * that we do not try to move it here.
 	 */
-	if (vp->v_usecount == 0) {
+	if (vp->v_usecount == 0 && !(vp->v_flag & VDOOMED)) {
 		simple_lock(&vnode_free_list_slock);
-		if ((vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb) &&
-			vnode_free_list.tqh_first != vp) {
-			TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
-			TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
-		}
+		TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
+		TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
 		simple_unlock(&vnode_free_list_slock);
 	}
 
@@ -1680,6 +1679,10 @@ vprint(label, vp)
 		strcat(buf, "|VBWAIT");
 	if (vp->v_flag & VALIASED)
 		strcat(buf, "|VALIASED");
+	if (vp->v_flag & VDOOMED)
+		strcat(buf, "|VDOOMED");
+	if (vp->v_flag & VFREE)
+		strcat(buf, "|VFREE");
 	if (buf[0] != '\0')
 		printf(" flags (%s)", &buf[1]);
 	if (vp->v_data == NULL) {
@@ -2255,20 +2258,28 @@ retn:
 }
 
 void
-vtouch(vp)
+vfree(vp)
 	struct vnode *vp;
 {
-	simple_lock(&vp->v_interlock);
-	if (vp->v_usecount) {
-		simple_unlock(&vp->v_interlock);
-		return;
-	}
-	if (simple_lock_try(&vnode_free_list_slock)) {
-		if (vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb) {
-			TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
-			TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
-		}
-		simple_unlock(&vnode_free_list_slock);
+	simple_lock(&vnode_free_list_slock);
+	if (vp->v_flag & VAGE) {
+		TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
+	} else {
+		TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
 	}
-	simple_unlock(&vp->v_interlock);
+	freevnodes++;
+	simple_unlock(&vnode_free_list_slock);
+	vp->v_flag &= ~VAGE;
+	vp->v_flag |= VFREE;
+}
+
+void
+vbusy(vp)
+	struct vnode *vp;
+{
+	simple_lock(&vnode_free_list_slock);
+	TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
+	freevnodes--;
+	simple_unlock(&vnode_free_list_slock);
+	vp->v_flag &= ~VFREE;
 }
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index 143521c..6358781 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -36,7 +36,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vfs_subr.c	8.31 (Berkeley) 5/26/95
- * $Id: vfs_subr.c,v 1.94 1997/08/26 04:36:17 dyson Exp $
+ * $Id: vfs_subr.c,v 1.95 1997/08/26 11:59:20 bde Exp $
  */
 
 /*
@@ -103,6 +103,7 @@ int vttoif_tab[9] = {
 }
 TAILQ_HEAD(freelst, vnode) vnode_free_list;	/* vnode free list */
 static u_long freevnodes = 0;
+SYSCTL_INT(_debug, OID_AUTO, freevnodes, CTLFLAG_RD, &freevnodes, 0, "");
 
 struct mntlist mountlist;	/* mounted filesystem list */
 struct simplelock mountlist_slock;
@@ -380,11 +381,11 @@ getnewvnode(tag, mp, vops, vpp)
 	}
 
 	if (vp) {
+		vp->v_flag |= VDOOMED;
 		TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
 		freevnodes--;
-		/* see comment on why 0xdeadb is set at end of vgone (below) */
-		vp->v_freelist.tqe_prev = (struct vnode **) 0xdeadb;
 		simple_unlock(&vnode_free_list_slock);
+		cache_purge(vp);
 		vp->v_lease = NULL;
 		if (vp->v_type != VBAD)
 			vgonel(vp, p);
@@ -418,13 +419,13 @@ getnewvnode(tag, mp, vops, vpp)
 		    M_VNODE, M_WAITOK);
 		bzero((char *) vp, sizeof *vp);
 		vp->v_dd = vp;
+		cache_purge(vp);
 		LIST_INIT(&vp->v_cache_src);
 		TAILQ_INIT(&vp->v_cache_dst);
 		numvnodes++;
 	}
 
 	vp->v_type = VNON;
-	cache_purge(vp);
 	vp->v_tag = tag;
 	vp->v_op = vops;
 	insmntque(vp, mp);
@@ -582,7 +583,7 @@ bgetvp(vp, bp)
 
 	if (bp->b_vp)
 		panic("bgetvp: not free");
-	VHOLD(vp);
+	vhold(vp);
 	bp->b_vp = vp;
 	if (vp->v_type == VBLK || vp->v_type == VCHR)
 		bp->b_dev = vp->v_rdev;
@@ -618,7 +619,7 @@ brelvp(bp)
 
 	vp = bp->b_vp;
 	bp->b_vp = (struct vnode *) 0;
-	HOLDRELE(vp);
+	vdrop(vp);
 }
 
 /*
@@ -678,8 +679,10 @@ reassignbuf(bp, newvp)
 	/*
 	 * Delete from old vnode list, if on one.
 	 */
-	if (bp->b_vnbufs.le_next != NOLIST)
+	if (bp->b_vnbufs.le_next != NOLIST) {
 		bufremvn(bp);
+		vdrop(bp->b_vp);
+	}
 	/*
 	 * If dirty, put on list of dirty buffers; otherwise insert onto list
 	 * of clean buffers.
@@ -700,6 +703,8 @@ reassignbuf(bp, newvp)
 	} else {
 		bufinsvn(bp, &newvp->v_cleanblkhd);
 	}
+	bp->b_vp = newvp;
+	vhold(bp->b_vp);
 	splx(s);
 }
 
@@ -836,13 +841,9 @@ vget(vp, flags, p)
 		tsleep((caddr_t)vp, PINOD, "vget", 0);
 		return (ENOENT);
 	}
-	if (vp->v_usecount == 0) {
-		simple_lock(&vnode_free_list_slock);
-		TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
-		simple_unlock(&vnode_free_list_slock);
-		freevnodes--;
-	}
 	vp->v_usecount++;
+	if (VSHOULDBUSY(vp))
+		vbusy(vp);
 	/*
 	 * Create the VM object, if needed
 	 */
@@ -1089,11 +1090,11 @@ vputrele(vp, put)
 		panic("vputrele: null vp");
 #endif
 	simple_lock(&vp->v_interlock);
-	vp->v_usecount--;
 
-	if ((vp->v_usecount == 1) &&
+	if ((vp->v_usecount == 2) &&
 		vp->v_object &&
 		(vp->v_object->flags & OBJ_VFS_REF)) {
+		vp->v_usecount--;
 		vp->v_object->flags &= ~OBJ_VFS_REF;
 		if (put) {
 			VOP_UNLOCK(vp, LK_INTERLOCK, p);
@@ -1104,7 +1105,8 @@ vputrele(vp, put)
 		return;
 	}
 
-	if (vp->v_usecount > 0) {
+	if (vp->v_usecount > 1) {
+		vp->v_usecount--;
 		if (put) {
 			VOP_UNLOCK(vp, LK_INTERLOCK, p);
 		} else {
@@ -1113,23 +1115,14 @@ vputrele(vp, put)
 		return;
 	}
 
-	if (vp->v_usecount < 0) {
+	if (vp->v_usecount < 1) {
 #ifdef DIAGNOSTIC
 		vprint("vputrele: negative ref count", vp);
 #endif
 		panic("vputrele: negative ref cnt");
 	}
-	simple_lock(&vnode_free_list_slock);
-	if (vp->v_flag & VAGE) {
-		vp->v_flag &= ~VAGE;
-		if(vp->v_tag != VT_TFS)
-			TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
-	} else {
-		if(vp->v_tag != VT_TFS)
-			TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
-	}
-	freevnodes++;
-	simple_unlock(&vnode_free_list_slock);
+
+	vp->v_holdcnt++; 	/* Make sure vnode isn't recycled */
 
 	/*
 	 * If we are doing a vput, the node is already locked, and we must
@@ -1139,8 +1132,18 @@ vputrele(vp, put)
 	if (put) {
 		simple_unlock(&vp->v_interlock);
 		VOP_INACTIVE(vp, p);
+		simple_lock(&vp->v_interlock);
+		vp->v_usecount--;
+		vp->v_holdcnt--;
+		if (VSHOULDFREE(vp))
+			vfree(vp);
+		simple_unlock(&vp->v_interlock);
 	} else if (vn_lock(vp, LK_EXCLUSIVE | LK_INTERLOCK, p) == 0) {
 		VOP_INACTIVE(vp, p);
+		vp->v_usecount--;
+		vp->v_holdcnt--;
+		if (VSHOULDFREE(vp))
+			vfree(vp);
 	}
 }
 
@@ -1161,9 +1164,8 @@ vrele(vp)
 	vputrele(vp, 0);
 }
 
-#ifdef DIAGNOSTIC
 /*
- * Page or buffer structure gets a reference.
+ * Somebody doesn't want the vnode recycled.
  */
 void
 vhold(vp)
@@ -1172,14 +1174,16 @@ vhold(vp)
 
 	simple_lock(&vp->v_interlock);
 	vp->v_holdcnt++;
+	if (VSHOULDBUSY(vp))
+		vbusy(vp);
 	simple_unlock(&vp->v_interlock);
 }
 
 /*
- * Page or buffer structure frees a reference.
+ * One less who cares about this vnode.
  */
 void
-holdrele(vp)
+vdrop(vp)
 	register struct vnode *vp;
 {
 
@@ -1187,9 +1191,10 @@ holdrele(vp)
 	if (vp->v_holdcnt <= 0)
 		panic("holdrele: holdcnt");
 	vp->v_holdcnt--;
+	if (VSHOULDFREE(vp))
+		vfree(vp);
 	simple_unlock(&vp->v_interlock);
 }
-#endif /* DIAGNOSTIC */
 
 /*
  * Remove any vnodes in the vnode table belonging to mount point mp.
@@ -1572,17 +1577,11 @@ vgonel(vp, p)
 	 * after calling vgone. If the reference count were
 	 * incremented first, vgone would (incorrectly) try to
 	 * close the previous instance of the underlying object.
-	 * So, the back pointer is explicitly set to `0xdeadb' in
-	 * getnewvnode after removing it from the freelist to ensure
-	 * that we do not try to move it here.
 	 */
-	if (vp->v_usecount == 0) {
+	if (vp->v_usecount == 0 && !(vp->v_flag & VDOOMED)) {
 		simple_lock(&vnode_free_list_slock);
-		if ((vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb) &&
-			vnode_free_list.tqh_first != vp) {
-			TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
-			TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
-		}
+		TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
+		TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
 		simple_unlock(&vnode_free_list_slock);
 	}
 
@@ -1680,6 +1679,10 @@ vprint(label, vp)
 		strcat(buf, "|VBWAIT");
 	if (vp->v_flag & VALIASED)
 		strcat(buf, "|VALIASED");
+	if (vp->v_flag & VDOOMED)
+		strcat(buf, "|VDOOMED");
+	if (vp->v_flag & VFREE)
+		strcat(buf, "|VFREE");
 	if (buf[0] != '\0')
 		printf(" flags (%s)", &buf[1]);
 	if (vp->v_data == NULL) {
@@ -2255,20 +2258,28 @@ retn:
 }
 
 void
-vtouch(vp)
+vfree(vp)
 	struct vnode *vp;
 {
-	simple_lock(&vp->v_interlock);
-	if (vp->v_usecount) {
-		simple_unlock(&vp->v_interlock);
-		return;
-	}
-	if (simple_lock_try(&vnode_free_list_slock)) {
-		if (vp->v_freelist.tqe_prev != (struct vnode **)0xdeadb) {
-			TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
-			TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
-		}
-		simple_unlock(&vnode_free_list_slock);
+	simple_lock(&vnode_free_list_slock);
+	if (vp->v_flag & VAGE) {
+		TAILQ_INSERT_HEAD(&vnode_free_list, vp, v_freelist);
+	} else {
+		TAILQ_INSERT_TAIL(&vnode_free_list, vp, v_freelist);
 	}
-	simple_unlock(&vp->v_interlock);
+	freevnodes++;
+	simple_unlock(&vnode_free_list_slock);
+	vp->v_flag &= ~VAGE;
+	vp->v_flag |= VFREE;
+}
+
+void
+vbusy(vp)
+	struct vnode *vp;
+{
+	simple_lock(&vnode_free_list_slock);
+	TAILQ_REMOVE(&vnode_free_list, vp, v_freelist);
+	freevnodes--;
+	simple_unlock(&vnode_free_list_slock);
+	vp->v_flag &= ~VFREE;
 }
diff --git a/sys/sys/vnode.h b/sys/sys/vnode.h
index 4c5225d..fac5979 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 1.45 1997/08/18 03:29:08 fsmp Exp $
+ * $Id: vnode.h,v 1.46 1997/08/26 07:32:46 phk Exp $
  */
 
 #ifndef _SYS_VNODE_H_
@@ -141,6 +141,8 @@ struct vnode {
 #define	VAGE		0x08000	/* Insert vnode at head of free list */
 #define	VOLOCK		0x10000	/* vnode is locked waiting for an object */
 #define	VOWANT		0x20000	/* a process is waiting for VOLOCK */
+#define	VDOOMED		0x40000	/* This vnode is being recycled */
+#define	VFREE		0x80000	/* This vnode is on the freelist */
 
 /*
  * Vnode attributes.  A field value of VNOVAL represents a field whose value
@@ -221,35 +223,12 @@ extern int		vttoif_tab[];
 #define	V_SAVEMETA	0x0002		/* vinvalbuf: leave indirect blocks */
 #define	REVOKEALL	0x0001		/* vop_revoke: revoke all aliases */
 
-#ifdef DIAGNOSTIC
-#define	HOLDRELE(vp)	holdrele(vp)
-#define	VATTR_NULL(vap)	vattr_null(vap)
-#define	VHOLD(vp)	vhold(vp)
 #define	VREF(vp)	vref(vp)
 
-void	holdrele __P((struct vnode *));
-void	vhold __P((struct vnode *));
-void 	vref __P((struct vnode *vp));
+#ifdef DIAGNOSTIC
+#define	VATTR_NULL(vap)	vattr_null(vap)
 #else
 #define	VATTR_NULL(vap)	(*(vap) = va_null)	/* initialize a vattr */
-#define	HOLDRELE(vp)	holdrele(vp)		/* decrease buf or page ref */
-static __inline void
-holdrele(struct vnode *vp)
-{
-	simple_lock(&vp->v_interlock);
-	vp->v_holdcnt--;
-	simple_unlock(&vp->v_interlock);
-}
-#define	VHOLD(vp)	vhold(vp)		/* increase buf or page ref */
-static __inline void
-vhold(struct vnode *vp)
-{
-	simple_lock(&vp->v_interlock);
-	vp->v_holdcnt++;
-	simple_unlock(&vp->v_interlock);
-}
-#define	VREF(vp)	vref(vp)		/* increase reference */
-void 	vref __P((struct vnode *vp));
 #endif /* DIAGNOSTIC */
 
 #define	NULLVP	((struct vnode *)NULL)
@@ -288,6 +267,15 @@ extern void	(*lease_updatetime) __P((int deltat));
 	do { if(lease_updatetime) lease_updatetime(dt); } while(0)
 #endif /* NFS */
 
+#define VSHOULDFREE(vp)	\
+	(!((vp)->v_flag & (VFREE|VDOOMED)) && \
+	 !(vp)->v_holdcnt && !(vp)->v_usecount)
+
+#define VSHOULDBUSY(vp)	\
+	(((vp)->v_flag & VFREE) && \
+	 ((vp)->v_holdcnt || (vp)->v_usecount))
+
+
 #endif /* KERNEL */
 
 
@@ -482,12 +470,16 @@ int 	getnewvnode __P((enum vtagtype tag,
 void	insmntque __P((struct vnode *vp, struct mount *mp));
 int	lease_check __P((struct vop_lease_args *ap));
 void 	vattr_null __P((struct vattr *vap));
+void	vbusy __P((struct vnode *));
 int 	vcount __P((struct vnode *vp));
+void	vdrop __P((struct vnode *));
 int	vfinddev __P((dev_t dev, enum vtype type, struct vnode **vpp));
+void	vfree __P((struct vnode *));
 void	vfs_opv_init __P((struct vnodeopv_desc **them));
 int	vflush __P((struct mount *mp, struct vnode *skipvp, int flags));
 int 	vget __P((struct vnode *vp, int lockflag, struct proc *p));
 void 	vgone __P((struct vnode *vp));
+void	vhold __P((struct vnode *));
 int	vinvalbuf __P((struct vnode *vp, int save, struct ucred *cred,
 	    struct proc *p, int slpflag, int slptimeo));
 void	vprint __P((char *label, struct vnode *vp));
@@ -514,8 +506,8 @@ int	vop_revoke __P((struct vop_revoke_args *));
 struct vnode *
 	checkalias __P((struct vnode *vp, dev_t nvp_rdev, struct mount *mp));
 void 	vput __P((struct vnode *vp));
+void 	vref __P((struct vnode *vp));
 void 	vrele __P((struct vnode *vp));
-void	vtouch __P((struct vnode *vp));
 #endif /* KERNEL */
 
 #endif /* !_SYS_VNODE_H_ */
diff --git a/sys/ufs/lfs/lfs_segment.c b/sys/ufs/lfs/lfs_segment.c
index d09a185..59206c4 100644
--- a/sys/ufs/lfs/lfs_segment.c
+++ b/sys/ufs/lfs/lfs_segment.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)lfs_segment.c	8.10 (Berkeley) 6/10/95
- * $Id: lfs_segment.c,v 1.22 1997/06/15 17:56:46 dyson Exp $
+ * $Id: lfs_segment.c,v 1.23 1997/08/02 14:33:20 bde Exp $
  */
 
 #include <sys/param.h>
@@ -1222,7 +1222,7 @@ lfs_vref(vp)
 
 	if ((vp->v_flag & VXLOCK) ||	/* XXX */
 	    (vp->v_usecount == 0 &&
-	     vp->v_freelist.tqe_prev == (struct vnode **)0xdeadb))
+	     vp->v_flag & VDOOMED))
 		return(1);
 	return (vget(vp, 0, p));
 }
diff --git a/sys/vm/vm_swap.c b/sys/vm/vm_swap.c
index 6082278..9fc4935 100644
--- a/sys/vm/vm_swap.c
+++ b/sys/vm/vm_swap.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)vm_swap.c	8.5 (Berkeley) 2/17/94
- * $Id: vm_swap.c,v 1.42 1997/02/22 09:48:40 peter Exp $
+ * $Id: vm_swap.c,v 1.43 1997/03/23 03:37:54 bde Exp $
  */
 
 #include <sys/param.h>
@@ -136,7 +136,7 @@ swstrategy(bp)
 		biodone(bp);
 		return;
 	}
-	VHOLD(sp->sw_vp);
+	vhold(sp->sw_vp);
 	if ((bp->b_flags & B_READ) == 0) {
 		vp = bp->b_vp;
 		if (vp) {