From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with ESMTP id CF58E6B0099 for ; Mon, 23 Feb 2009 06:42:24 -0500 (EST) Date: Mon, 23 Feb 2009 11:42:21 +0000 From: Mel Gorman Subject: Re: [PATCH 11/20] Inline get_page_from_freelist() in the fast-path Message-ID: <20090223114221.GD6740@csn.ul.ie> References: <1235344649-18265-1-git-send-email-mel@csn.ul.ie> <1235344649-18265-12-git-send-email-mel@csn.ul.ie> <84144f020902222321q12f54ed8wae3865064bb6e43@mail.gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <84144f020902222321q12f54ed8wae3865064bb6e43@mail.gmail.com> Sender: owner-linux-mm@kvack.org To: Pekka Enberg Cc: Linux Memory Management List , Rik van Riel , KOSAKI Motohiro , Christoph Lameter , Johannes Weiner , Nick Piggin , Linux Kernel Mailing List , Lin Ming , Zhang Yanmin List-ID: On Mon, Feb 23, 2009 at 09:21:09AM +0200, Pekka Enberg wrote: > On Mon, Feb 23, 2009 at 1:17 AM, Mel Gorman wrote: > > In the best-case scenario, use an inlined version of > > get_page_from_freelist(). This increases the size of the text but avoids > > time spent pushing arguments onto the stack. > > > > Signed-off-by: Mel Gorman > > It's not obvious to me why this would be a huge win so I suppose this > patch description could use numbers. I don't have the exact numbers from the profiles any more but the function entry and exit was about 1/20th of the cost of the path when zeroing pages is not taken into account. > Note: we used to do tricks like > these in slab.c but got rid of most of them to reduce kernel text size > which is probably why the patch seems bit backwards to me. > I'll be rechecking this patch in particular because it's likely the biggest text bloat in the entire series. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org