Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754911AbYJWHKZ (ORCPT ); Thu, 23 Oct 2008 03:10:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751974AbYJWHKJ (ORCPT ); Thu, 23 Oct 2008 03:10:09 -0400 Received: from courier.cs.helsinki.fi ([128.214.9.1]:52388 "EHLO mail.cs.helsinki.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751872AbYJWHKH (ORCPT ); Thu, 23 Oct 2008 03:10:07 -0400 Subject: Re: SLUB defrag pull request? From: Pekka Enberg To: Miklos Szeredi Cc: cl@linux-foundation.org, nickpiggin@yahoo.com.au, hugh@veritas.com, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org In-Reply-To: References: <1223883004.31587.15.camel@penberg-laptop> <48FE6306.6020806@linux-foundation.org> <84144f020810221348j536f0d84vca039ff32676e2cc@mail.gmail.com> Content-Type: text/plain; charset=UTF-8 Date: Thu, 23 Oct 2008 10:10:31 +0300 Message-Id: <1224745831.25814.21.camel@penberg-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1054 Lines: 27 Hi Miklos, On Thu, 2008-10-23 at 00:10 +0200, Miklos Szeredi wrote: > Actually, no: looking at the slub code it already makes sure that > objects are neither poisoned, nor touched in any way _if_ there is a > constructor for the object. And for good reason too, otherwise a > reused object would contain rubbish after a second allocation. There's no inherent reason why we cannot poison slab caches with a constructor. As a matter of fact SLAB does it which is probably why I got confused here. The only thing that needs to disable slab poisoning by design is SLAB_DESTROY_BY_RCU. But for SLUB, you're obviously right. On Thu, 2008-10-23 at 00:10 +0200, Miklos Szeredi wrote: > Come on guys, you should be the experts in this thing! Yeah, I know. Yet you're stuck with us. That's sad. Pekka -- 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/