svn commit: r225388 - stable/8/sys/vm

[Konstantin Belousov]

Author: kib
Date: Mon Sep  5 08:41:57 2011
New Revision: 225388
URL: http://svn.freebsd.org/changeset/base/225388

Log:
  MFC r225076:
  Apply the limit to avoid the overflows in the radix tree subr_blist.c
  after the conversion of the swap device size to the page size units,
  not before.

Modified:
  stable/8/sys/vm/swap_pager.c
Directory Properties:
  stable/8/sys/   (props changed)
  stable/8/sys/amd64/include/xen/   (props changed)
  stable/8/sys/cddl/contrib/opensolaris/   (props changed)
  stable/8/sys/contrib/dev/acpica/   (props changed)
  stable/8/sys/contrib/pf/   (props changed)

Modified: stable/8/sys/vm/swap_pager.c
==============================================================================
--- stable/8/sys/vm/swap_pager.c	Mon Sep  5 07:59:23 2011	(r225387)
+++ stable/8/sys/vm/swap_pager.c	Mon Sep  5 08:41:57 2011	(r225388)
@@ -2083,16 +2083,6 @@ swaponsomething(struct vnode *vp, void *
 	u_long mblocks;
 
 	/*
-	 * If we go beyond this, we get overflows in the radix
-	 * tree bitmap code.
-	 */
-	mblocks = 0x40000000 / BLIST_META_RADIX;
-	if (nblks > mblocks) {
-		printf("WARNING: reducing size to maximum of %lu blocks per swap unit\n",
-			mblocks);
-		nblks = mblocks;
-	}
-	/*
 	 * nblks is in DEV_BSIZE'd chunks, convert to PAGE_SIZE'd chunks.
 	 * First chop nblks off to page-align it, then convert.
 	 * 
@@ -2101,6 +2091,18 @@ swaponsomething(struct vnode *vp, void *
 	nblks &= ~(ctodb(1) - 1);
 	nblks = dbtoc(nblks);
 
+	/*
+	 * If we go beyond this, we get overflows in the radix
+	 * tree bitmap code.
+	 */
+	mblocks = 0x40000000 / BLIST_META_RADIX;
+	if (nblks > mblocks) {
+		printf(
+    "WARNING: reducing swap size to maximum of %luMB per unit\n",
+		    mblocks / 1024 / 1024 * PAGE_SIZE);
+		nblks = mblocks;
+	}
+
 	sp = malloc(sizeof *sp, M_VMPGDATA, M_WAITOK | M_ZERO);
 	sp->sw_vp = vp;
 	sp->sw_id = id;