From owner-svn-src-head@FreeBSD.ORG  Tue Jan  3 03:29:01 2012
Return-Path: <owner-svn-src-head@FreeBSD.ORG>
Delivered-To: svn-src-head@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id CD8F61065673;
	Tue,  3 Jan 2012 03:29:01 +0000 (UTC) (envelope-from alc@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id B7C128FC0A;
	Tue,  3 Jan 2012 03:29:01 +0000 (UTC)
Received: from svn.freebsd.org (localhost [127.0.0.1])
	by svn.freebsd.org (8.14.4/8.14.4) with ESMTP id q033T1CT003058;
	Tue, 3 Jan 2012 03:29:01 GMT (envelope-from alc@svn.freebsd.org)
Received: (from alc@localhost)
	by svn.freebsd.org (8.14.4/8.14.4/Submit) id q033T1wF003056;
	Tue, 3 Jan 2012 03:29:01 GMT (envelope-from alc@svn.freebsd.org)
Message-Id: <201201030329.q033T1wF003056@svn.freebsd.org>
From: Alan Cox <alc@FreeBSD.org>
Date: Tue, 3 Jan 2012 03:29:01 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-all@freebsd.org,
	svn-src-head@freebsd.org
X-SVN-Group: head
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r229363 - head/sys/fs/tmpfs
X-BeenThere: svn-src-head@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: SVN commit messages for the src tree for head/-current
	<svn-src-head.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-head>,
	<mailto:svn-src-head-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-head>
List-Post: <mailto:svn-src-head@freebsd.org>
List-Help: <mailto:svn-src-head-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-head>,
	<mailto:svn-src-head-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 03 Jan 2012 03:29:01 -0000

Author: alc
Date: Tue Jan  3 03:29:01 2012
New Revision: 229363
URL: http://svn.freebsd.org/changeset/base/229363

Log:
  Don't pass VM_ALLOC_ZERO to vm_page_grab() in tmpfs_mappedwrite() and
  tmpfs_nocacheread().  It is both unnecessary and a pessimization.  It
  results in either the page being zeroed twice or zeroed first and then
  overwritten by an I/O operation.
  
  MFC after:	3 weeks

Modified:
  head/sys/fs/tmpfs/tmpfs_vnops.c

Modified: head/sys/fs/tmpfs/tmpfs_vnops.c
==============================================================================
--- head/sys/fs/tmpfs/tmpfs_vnops.c	Tue Jan  3 01:07:02 2012	(r229362)
+++ head/sys/fs/tmpfs/tmpfs_vnops.c	Tue Jan  3 03:29:01 2012	(r229363)
@@ -442,7 +442,7 @@ tmpfs_nocacheread(vm_object_t tobj, vm_p
 	VM_OBJECT_LOCK(tobj);
 	vm_object_pip_add(tobj, 1);
 	m = vm_page_grab(tobj, idx, VM_ALLOC_WIRED |
-	    VM_ALLOC_ZERO | VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
+	    VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
 	if (m->valid != VM_PAGE_BITS_ALL) {
 		if (vm_pager_has_page(tobj, idx, NULL, NULL)) {
 			error = vm_pager_get_pages(tobj, &m, 1, 0);
@@ -666,7 +666,7 @@ nocache:
 	VM_OBJECT_LOCK(tobj);
 	vm_object_pip_add(tobj, 1);
 	tpg = vm_page_grab(tobj, idx, VM_ALLOC_WIRED |
-	    VM_ALLOC_ZERO | VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
+	    VM_ALLOC_NORMAL | VM_ALLOC_RETRY);
 	if (tpg->valid != VM_PAGE_BITS_ALL) {
 		if (vm_pager_has_page(tobj, idx, NULL, NULL)) {
 			error = vm_pager_get_pages(tobj, &tpg, 1, 0);