From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1422726AbWATBqk (ORCPT ); Thu, 19 Jan 2006 20:46:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1422727AbWATBqk (ORCPT ); Thu, 19 Jan 2006 20:46:40 -0500 Received: from omx1-ext.sgi.com ([192.48.179.11]:34785 "EHLO omx1.americas.sgi.com") by vger.kernel.org with ESMTP id S1422726AbWATBqj (ORCPT ); Thu, 19 Jan 2006 20:46:39 -0500 Date: Thu, 19 Jan 2006 17:46:29 -0800 (PST) From: Christoph Lameter To: Andrew Morton cc: linux-kernel@vger.kernel.org Subject: Re: [PATCH] shrink_list: Use of && instead || leads to unintended writing of pages In-Reply-To: <20060119172032.04bad017.akpm@osdl.org> Message-ID: References: <20060119164341.0fb9c7e3.akpm@osdl.org> <20060119172032.04bad017.akpm@osdl.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org This is all crap. may_writepage needs to do as it says and control write behavior .... We can set the proper writemode in try_to_free_pages based on the laptop mode. Then everything falls into the proper place. [PATCH] Implement sane function of sc->may_writepage Make sc->may_writepage control the writeout behavior of shrink_list. Remove the laptop_mode trick from shrink_list and instead set may_writepage in try_to_free_pages properly. Signed-off-by: Christoph Lameter Index: linux-2.6.16-rc1-mm1/mm/vmscan.c =================================================================== --- linux-2.6.16-rc1-mm1.orig/mm/vmscan.c 2006-01-19 15:50:19.000000000 -0800 +++ linux-2.6.16-rc1-mm1/mm/vmscan.c 2006-01-19 17:42:07.000000000 -0800 @@ -491,7 +491,7 @@ static int shrink_list(struct list_head goto keep_locked; if (!may_enter_fs) goto keep_locked; - if (laptop_mode && !sc->may_writepage) + if (!sc->may_writepage) goto keep_locked; /* Page is dirty, try to write it out here */ @@ -1409,7 +1409,7 @@ int try_to_free_pages(struct zone **zone int i; sc.gfp_mask = gfp_mask; - sc.may_writepage = 0; + sc.may_writepage = !laptop_mode; sc.may_swap = 1; inc_page_state(allocstall); @@ -1512,7 +1512,7 @@ loop_again: total_scanned = 0; total_reclaimed = 0; sc.gfp_mask = GFP_KERNEL; - sc.may_writepage = 0; + sc.may_writepage = 1; sc.may_swap = 1; sc.nr_mapped = read_page_state(nr_mapped);