From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1033692AbXEID1j (ORCPT ); Tue, 8 May 2007 23:27:39 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S968834AbXEID1L (ORCPT ); Tue, 8 May 2007 23:27:11 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:54770 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S969557AbXEID1J (ORCPT ); Tue, 8 May 2007 23:27:09 -0400 Date: Tue, 8 May 2007 20:27:09 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Nick Piggin cc: Matt Mackall , David Miller , akpm@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: + fix-spellings-of-slab-allocator-section-in-init-kconfig.patch added to -mm tree In-Reply-To: <46413D6A.6000502@yahoo.com.au> Message-ID: References: <20070509012725.GZ11115@waste.org> <20070508.185141.85412154.davem@davemloft.net> <46412BB5.1060605@yahoo.com.au> <20070509025634.GC11115@waste.org> <46413D6A.6000502@yahoo.com.au> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 9 May 2007, Nick Piggin wrote: > SLAB_DESTROY_BY_RCU is quite a nice way to mitigate some RCU freeing > overheads for small objects, so I'd expect it may see wider use in > future. Maybe all those users would be fine too, but it's a bit nasty > to have already tricky RCU semantics deviate... Signal handling is using RCU too right? > > I think if we want RCU to actually work, we want to run ->dtor in > > __kmem_cache_free? > > Yeah, thinko... thanks. According to SLAB code: RCU cannot have a dtor. kmem_cache_create() if (flags & SLAB_DESTROY_BY_RCU) BUG_ON(dtor);