From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f178.google.com (mail-ig0-f178.google.com [209.85.213.178]) by kanga.kvack.org (Postfix) with ESMTP id CBD116B006E for ; Fri, 21 Nov 2014 18:38:43 -0500 (EST) Received: by mail-ig0-f178.google.com with SMTP id hl2so468656igb.17 for ; Fri, 21 Nov 2014 15:38:43 -0800 (PST) Received: from mail.linuxfoundation.org (mail.linuxfoundation.org. [140.211.169.12]) by mx.google.com with ESMTPS id f4si5470020icx.73.2014.11.21.15.38.42 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 21 Nov 2014 15:38:43 -0800 (PST) Date: Fri, 21 Nov 2014 15:38:41 -0800 From: Andrew Morton 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> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: 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 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, 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