Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752854AbaKUXio (ORCPT ); Fri, 21 Nov 2014 18:38:44 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:58344 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752100AbaKUXim (ORCPT ); Fri, 21 Nov 2014 18:38:42 -0500 Date: Fri, 21 Nov 2014 15:38:41 -0800 From: Andrew Morton To: Joonsoo Kim Cc: Mel Gorman , Johannes Weiner , Minchan Kim , Dave Hansen , Michal Nazarewicz , Jungsoo Son , Ingo Molnar , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 7/7] mm/page_owner: correct owner information for early allocated pages Message-Id: <20141121153841.c15fa400fd5c76d3946523a8@linux-foundation.org> In-Reply-To: <1416557646-21755-8-git-send-email-iamjoonsoo.kim@lge.com> References: <1416557646-21755-1-git-send-email-iamjoonsoo.kim@lge.com> <1416557646-21755-8-git-send-email-iamjoonsoo.kim@lge.com> X-Mailer: Sylpheed 3.4.0beta7 (GTK+ 2.24.23; x86_64-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 On Fri, 21 Nov 2014 17:14:06 +0900 Joonsoo Kim wrote: > Extended memory to store page owner information is initialized some time > later than that page allocator starts. Until initialization, many pages > can be allocated and they have no owner information. This make debugging > using page owner harder, so some fixup will be helpful. > > This patch fix up this situation by setting fake owner information > immediately after page extension is initialized. Information doesn't > tell the right owner, but, at least, it can tell whether page is > allocated or not, more correctly. > > On my testing, this patch catches 13343 early allocated pages, although > they are mostly allocated from page extension feature. Anyway, after then, > there is no page left that it is allocated and has no page owner flag. We really should have a Documentation/vm/page_owner.txt which explains all this stuff, provides examples, etc. -- 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/