Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760034Ab2JYSHE (ORCPT ); Thu, 25 Oct 2012 14:07:04 -0400 Received: from mail-pa0-f46.google.com ([209.85.220.46]:35322 "EHLO mail-pa0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759076Ab2JYSHA (ORCPT ); Thu, 25 Oct 2012 14:07:00 -0400 Date: Thu, 25 Oct 2012 11:06:52 -0700 From: Tejun Heo To: Glauber Costa Cc: JoonSoo Kim , linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Mel Gorman , Andrew Morton , Michal Hocko , Johannes Weiner , kamezawa.hiroyu@jp.fujitsu.com, Christoph Lameter , David Rientjes , Pekka Enberg , devel@openvz.org, Pekka Enberg , Suleiman Souhlal Subject: Re: [PATCH v5 08/18] memcg: infrastructure to match an allocation to the right cache Message-ID: <20121025180652.GM11442@htj.dyndns.org> References: <1350656442-1523-1-git-send-email-glommer@parallels.com> <1350656442-1523-9-git-send-email-glommer@parallels.com> <50891CF2.3030400@parallels.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <50891CF2.3030400@parallels.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 777 Lines: 26 Hello, Glauber. On Thu, Oct 25, 2012 at 03:05:22PM +0400, Glauber Costa wrote: > > Is there any rmb() pair? > > As far as I know, without rmb(), wmb() doesn't guarantee anything. > > > > There should be. But it seems I missed it. Speaking of which, I should You probably can use read_barrier_depends(). > wmb() after the NULL assignment in release cache as well. And you probably don't need that. dangling pointer is protected by RCU and there isn't any memory accesses which can paired with that anyway. Thanks. -- tejun -- 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/