From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail202.messagelabs.com (mail202.messagelabs.com [216.82.254.227]) by kanga.kvack.org (Postfix) with ESMTP id A6A3C6B0078 for ; Thu, 21 Jan 2010 12:43:38 -0500 (EST) Received: from d01relay05.pok.ibm.com (d01relay05.pok.ibm.com [9.56.227.237]) by e3.ny.us.ibm.com (8.14.3/8.13.1) with ESMTP id o0LHXTKh030921 for ; Thu, 21 Jan 2010 12:33:29 -0500 Received: from d01av01.pok.ibm.com (d01av01.pok.ibm.com [9.56.224.215]) by d01relay05.pok.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o0LHhajZ137352 for ; Thu, 21 Jan 2010 12:43:36 -0500 Received: from d01av01.pok.ibm.com (loopback [127.0.0.1]) by d01av01.pok.ibm.com (8.14.3/8.13.1/NCO v10.0 AVout) with ESMTP id o0LHhZDT010999 for ; Thu, 21 Jan 2010 12:43:36 -0500 Subject: Re: [PATCH 04 of 30] clear compound mapping From: Dave Hansen In-Reply-To: References: Content-Type: text/plain Date: Thu, 21 Jan 2010 09:43:30 -0800 Message-Id: <1264095810.32717.34483.camel@nimitz> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Andrea Arcangeli Cc: linux-mm@kvack.org, Marcelo Tosatti , Adam Litke , Avi Kivity , Izik Eidus , Hugh Dickins , Nick Piggin , Rik van Riel , Mel Gorman , Andi Kleen , Benjamin Herrenschmidt , Ingo Molnar , Mike Travis , KAMEZAWA Hiroyuki , Christoph Lameter , Chris Wright , Andrew Morton List-ID: On Thu, 2010-01-21 at 07:20 +0100, Andrea Arcangeli wrote: > Clear compound mapping for anonymous compound pages like it already happens for > regular anonymous pages. > diff --git a/mm/page_alloc.c b/mm/page_alloc.c > --- a/mm/page_alloc.c > +++ b/mm/page_alloc.c > @@ -584,6 +584,8 @@ static void __free_pages_ok(struct page > > kmemcheck_free_shadow(page, order); > > + if (PageAnon(page)) > + page->mapping = NULL; > for (i = 0 ; i < (1 << order) ; ++i) > bad += free_pages_check(page + i); > if (bad) This one may at least need a bit of an enhanced patch description. I didn't immediately remember that __free_pages_ok() is only actually called for compound pages. Would it make more sense to pull the page->mapping=NULL out of free_hot_cold_page(), and just put a single one in __free_pages()? I guess we'd also need one in free_compound_page() since it calls __free_pages_ok() directly. But, if this patch were putting modifying free_compound_page() it would at least be super obvious what was going on. -- Dave -- 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