Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751474AbZL1DSn (ORCPT ); Sun, 27 Dec 2009 22:18:43 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751340AbZL1DSm (ORCPT ); Sun, 27 Dec 2009 22:18:42 -0500 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:35335 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751282AbZL1DSm (ORCPT ); Sun, 27 Dec 2009 22:18:42 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Minchan Kim Subject: Re: [PATCH -mmotm-2009-12-10-17-19] Prevent churning of zero page in LRU list. Cc: kosaki.motohiro@jp.fujitsu.com, Andrew Morton , lkml , linux-mm , Hugh Dickins , Rik van Riel In-Reply-To: <20091228115315.76b1ecd0.minchan.kim@barrios-desktop> References: <20091228115315.76b1ecd0.minchan.kim@barrios-desktop> Message-Id: <20091228121758.A67E.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.50.07 [ja] Date: Mon, 28 Dec 2009 12:18:38 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 707 Lines: 22 > > VM doesn't add zero page to LRU list. > It means zero page's churning in LRU list is pointless. > > As a matter of fact, zero page can't be promoted by mark_page_accessed > since it doesn't have PG_lru. > > This patch prevent unecessary mark_page_accessed call of zero page > alghouth caller want FOLL_TOUCH. > > Signed-off-by: Minchan Kim Looks good to me. Reviewed-by: KOSAKI Motohiro -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/