From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753492AbWKFUVy (ORCPT ); Mon, 6 Nov 2006 15:21:54 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753493AbWKFUVy (ORCPT ); Mon, 6 Nov 2006 15:21:54 -0500 Received: from sj-iport-3-in.cisco.com ([171.71.176.72]:51849 "EHLO sj-iport-3.cisco.com") by vger.kernel.org with ESMTP id S1753492AbWKFUVx (ORCPT ); Mon, 6 Nov 2006 15:21:53 -0500 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AgAAADooT0WrR7PDh2dsb2JhbACMSQEBAQgOKg X-IronPort-AV: i="4.09,392,1157353200"; d="scan'208"; a="448365265:sNHT26637512" To: Ingo Molnar Cc: Jason Baron , linux-kernel@vger.kernel.org, arjan@infradead.org Subject: Re: locking hierarchy based on lockdep X-Message-Flag: Warning: May contain useful information References: <20061106200529.GA15370@elte.hu> From: Roland Dreier Date: Mon, 06 Nov 2006 12:21:50 -0800 In-Reply-To: <20061106200529.GA15370@elte.hu> (Ingo Molnar's message of "Mon, 6 Nov 2006 21:05:29 +0100") Message-ID: User-Agent: Gnus/5.1007 (Gnus v5.10.7) XEmacs/21.4.19 (linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-OriginalArrivalTime: 06 Nov 2006 20:21:51.0056 (UTC) FILETIME=[31596500:01C701E1] Authentication-Results: sj-dkim-3.cisco.com; header.From=rdreier@cisco.com; dkim=pass ( sig from cisco.com verified; ); Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > i like your idea of using lockdep to document locking hierarchies. Yes, it's definitely a cool idea. I think the current implementation is not that useful, since it jams all the unrelated kernel locks into a single ordered list, when in fact many locks simply have no ordering relationship at all because they're never both taken. This makes the list hard to read and in fact loses the information of which locks have been taken together. - R.