From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f182.google.com (mail-ig0-f182.google.com [209.85.213.182]) by kanga.kvack.org (Postfix) with ESMTP id D94F16B006E for ; Wed, 8 Oct 2014 03:10:16 -0400 (EDT) Received: by mail-ig0-f182.google.com with SMTP id hn18so7366874igb.3 for ; Wed, 08 Oct 2014 00:10:16 -0700 (PDT) Received: from resqmta-po-11v.sys.comcast.net (resqmta-po-11v.sys.comcast.net. [2001:558:fe16:19:96:114:154:170]) by mx.google.com with ESMTPS id hs7si1573320igb.22.2014.10.08.00.10.14 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 08 Oct 2014 00:10:15 -0700 (PDT) Date: Wed, 8 Oct 2014 02:10:13 -0500 (CDT) From: Christoph Lameter Subject: Re: [PATCH 5/5] mm: poison page struct In-Reply-To: <5434630C.3070006@intel.com> Message-ID: References: <1412041639-23617-1-git-send-email-sasha.levin@oracle.com> <1412041639-23617-6-git-send-email-sasha.levin@oracle.com> <5434630C.3070006@intel.com> Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Dave Hansen Cc: Sasha Levin , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, hughd@google.com, mgorman@suse.de On Tue, 7 Oct 2014, Dave Hansen wrote: > Does this break slub's __cmpxchg_double_slab trick? I thought it > required page->freelist and page->counters to be doubleword-aligned. Sure that would be required for it to work. > It's not like we really require this optimization when we're debugging, > but trying to use it will unnecessarily slow things down. Debugging by inserting more data into the page struct will already cause a significant slow down because the cache footprint of key functions will increase significantly. I would think that using the fallback functions is reasonable in this scenario, -- 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