From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755841AbZLUKuR (ORCPT ); Mon, 21 Dec 2009 05:50:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754748AbZLUKuQ (ORCPT ); Mon, 21 Dec 2009 05:50:16 -0500 Received: from one.firstfloor.org ([213.235.205.2]:59034 "EHLO one.firstfloor.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754616AbZLUKuP (ORCPT ); Mon, 21 Dec 2009 05:50:15 -0500 Date: Mon, 21 Dec 2009 11:50:10 +0100 From: Andi Kleen To: Alexey Dobriyan Cc: andi@firstfloor.org, linux-kernel@vger.kernel.org, ebiederm@xmission.com, paulmck@linux.vnet.ibm.com Subject: Re: [PATCH] [0/11] SYSCTL: Use RCU to avoid races with string sysctls Message-ID: <20091221105010.GC25372@basil.fritz.box> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Dec 21, 2009 at 09:57:32AM +0200, Alexey Dobriyan wrote: > > new = alloc_rcu_string(MAX_GLOBAL_SIZE, GFP_KERNEL); > > I think adding failure mode is not right. > We can get away with per-sysctl-string spinlock and not introduce yet > another API. You mean when running out of memory here? When this runs out of memory the system will be not usable anyways and on the last legs and likely in a deadly swap storm. -Andi -- ak@linux.intel.com -- Speaking for myself only.