Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934971AbXLNBLj (ORCPT ); Thu, 13 Dec 2007 20:11:39 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757085AbXLNBL1 (ORCPT ); Thu, 13 Dec 2007 20:11:27 -0500 Received: from smtp2.linux-foundation.org ([207.189.120.14]:57738 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751118AbXLNBLZ (ORCPT ); Thu, 13 Dec 2007 20:11:25 -0500 Date: Thu, 13 Dec 2007 17:11:03 -0800 From: Andrew Morton To: James Bottomley Cc: liml@rtr.ca, jens.axboe@oracle.com, lkml@rtr.ca, matthew@wil.cx, linux-ide@vger.kernel.org, linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org, linux-mm@kvack.org, mel@csn.ul.ie Subject: Re: [PATCH] fix page_alloc for larger I/O segments (improved) Message-Id: <20071213171103.17c3b924.akpm@linux-foundation.org> In-Reply-To: <1197593849.3154.62.camel@localhost.localdomain> References: <20071213185326.GQ26334@parisc-linux.org> <4761821F.3050602@rtr.ca> <20071213192633.GD10104@kernel.dk> <4761883A.7050908@rtr.ca> <476188C4.9030802@rtr.ca> <20071213193937.GG10104@kernel.dk> <47618B0B.8020203@rtr.ca> <20071213195350.GH10104@kernel.dk> <20071213200219.GI10104@kernel.dk> <476190BE.9010405@rtr.ca> <20071213200958.GK10104@kernel.dk> <20071213140207.111f94e2.akpm@linux-foundation.org> <1197584106.3154.55.camel@localhost.localdomain> <20071213142935.47ff19d9.akpm@linux-foundation.org> <4761B32A.3070201@rtr.ca> <4761BCB4.1060601@rtr.ca> <4761C8E4.2010900@rtr.ca> <4761CE88.9070406@rtr.ca> <20071213163726.3bb601fa.akpm@linux-foundation.org> <4761D160.7060603@rtr.ca> <4761D279.6050500@rtr.ca> <1197593849.3154.62.camel@localhost.localdomain> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1619 Lines: 48 On Thu, 13 Dec 2007 19:57:29 -0500 James Bottomley wrote: > > On Thu, 2007-12-13 at 19:46 -0500, Mark Lord wrote: > > "Improved version", more similar to the 2.6.23 code: > > > > Fix page allocator to give better chance of larger contiguous segments (again). > > > > Signed-off-by: Mark Lord > --- > > > > --- old/mm/page_alloc.c 2007-12-13 19:25:15.000000000 -0500 > > +++ linux-2.6/mm/page_alloc.c 2007-12-13 19:43:07.000000000 -0500 > > @@ -760,7 +760,7 @@ > > struct page *page = __rmqueue(zone, order, migratetype); > > if (unlikely(page == NULL)) > > break; > > - list_add(&page->lru, list); > > + list_add_tail(&page->lru, list); > > Could we put a big comment above this explaining to the would be vm > tweakers why this has to be a list_add_tail, so we don't end up back in > this position after another two years? > Already done ;) --- a/mm/page_alloc.c~fix-page_alloc-for-larger-i-o-segments-fix +++ a/mm/page_alloc.c @@ -847,6 +847,10 @@ static int rmqueue_bulk(struct zone *zon struct page *page = __rmqueue(zone, order, migratetype); if (unlikely(page == NULL)) break; + /* + * Doing a list_add_tail() here helps us to hand out pages in + * ascending physical-address order. + */ list_add_tail(&page->lru, list); set_page_private(page, migratetype); } _ -- 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/