Keep track of how many pages a vnode hold with vhold and vholdrele

so that we can get back the old behavior where a vnode with cached data
is less likely to be recycled than a vnode without cached data.

XXX - This is a brute-force solution - we do it where uvmexp.vnodepages
 are changed, I am not really sure it is correct but people have been
 very happy with the diff so far and want this in the tree.

2 files changed, 14 insertions, 6 deletions

diff --git a/sys/uvm/uvm_page.c b/sys/uvm/uvm_page.c
index 0da38fc51ed..ed2a8c6f601 100644
--- a/sys/uvm/uvm_page.c
+++ b/sys/uvm/uvm_page.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_page.c,v 1.37 2001/12/04 23:22:42 art Exp $	*/
+/*	$OpenBSD: uvm_page.c,v 1.38 2001/12/06 12:43:20 art Exp $	*/
 /*	$NetBSD: uvm_page.c,v 1.66 2001/09/10 21:19:43 chris Exp $	*/
 
 /*
@@ -197,10 +197,14 @@ uvm_pageremove(pg)
 	simple_unlock(&uvm.hashlock);
 	splx(s);
 
-	if (UVM_OBJ_IS_VTEXT(pg->uobject)) {
-		uvmexp.vtextpages--;
-	} else if (UVM_OBJ_IS_VNODE(pg->uobject)) {
-		uvmexp.vnodepages--;
+	if (UVM_OBJ_IS_VTEXT(pg->uobject) || UVM_OBJ_IS_VNODE(pg->uobject)) {
+		if (UVM_OBJ_IS_VNODE(pg->uobject))
+			uvmexp.vnodepages--;
+		else
+			uvmexp.vtextpages--;
+		s = splbio();
+		vholdrele((struct vnode *)pg->uobject);
+		splx(s);
 	}
 
 	/* object should be locked */
diff --git a/sys/uvm/uvm_vnode.c b/sys/uvm/uvm_vnode.c
index 180acc16e66..67ccf7d605c 100644
--- a/sys/uvm/uvm_vnode.c
+++ b/sys/uvm/uvm_vnode.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: uvm_vnode.c,v 1.29 2001/12/04 23:22:42 art Exp $	*/
+/*	$OpenBSD: uvm_vnode.c,v 1.30 2001/12/06 12:43:20 art Exp $	*/
 /*	$NetBSD: uvm_vnode.c,v 1.51 2001/08/17 05:53:02 chs Exp $	*/
 
 /*
@@ -899,6 +899,7 @@ uvn_findpage(uobj, offset, pgp, flags)
 	int flags;
 {
 	struct vm_page *pg;
+	int s;
 	UVMHIST_FUNC("uvn_findpage"); UVMHIST_CALLED(ubchist);
 	UVMHIST_LOG(ubchist, "vp %p off 0x%lx", uobj, offset,0,0);
 
@@ -932,6 +933,9 @@ uvn_findpage(uobj, offset, pgp, flags)
 			} else {
 				uvmexp.vnodepages++;
 			}
+			s = splbio();
+			vhold((struct vnode *)uobj);
+			splx(s);
 			UVMHIST_LOG(ubchist, "alloced",0,0,0,0);
 			break;
 		} else if (flags & UFP_NOCACHE) {