From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761426AbYFMHYn (ORCPT ); Fri, 13 Jun 2008 03:24:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754118AbYFMHYe (ORCPT ); Fri, 13 Jun 2008 03:24:34 -0400 Received: from mga02.intel.com ([134.134.136.20]:23442 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753852AbYFMHYd (ORCPT ); Fri, 13 Jun 2008 03:24:33 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.27,637,1204531200"; d="scan'208";a="292510611" Subject: Re: [BUGFIX] lockdep: output lock_class key instead of address for forward dependency output From: "Huang, Ying" To: Ingo Molnar Cc: Peter Zijlstra , linux-kernel@vger.kernel.org In-Reply-To: <20080613065809.GA28810@elte.hu> References: <1213339217.17201.6.camel@caritas-dev.intel.com> <20080613065809.GA28810@elte.hu> Content-Type: text/plain Content-Transfer-Encoding: 7bit Date: Fri, 13 Jun 2008 15:26:05 +0800 Message-Id: <1213341965.17201.15.camel@caritas-dev.intel.com> Mime-Version: 1.0 X-Mailer: Evolution 2.22.1 X-OriginalArrivalTime: 13 Jun 2008 07:24:04.0609 (UTC) FILETIME=[75A26F10:01C8CD26] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 2008-06-13 at 08:58 +0200, Ingo Molnar wrote: > * Huang, Ying wrote: > > > The key instead of address of lock_class should be output in > > /proc/lockdep when forward dependency is output, because key is > > output for lock_class itself as identifier too. > > > > This patch is based on x86/auto-latest branch of git-x86 tree, and has > > been tested on x86_64 platform. > > applied to tip/core/locking - thanks Ying. > > i'm wondering, can entry->class never be NULL here? As far as I know, it can never be NULL. Because entry is added into class->locks_after in following call chain: lock_acquire -> __lock_acquire -> validate_chain -> check_prevs_add -> check_prev_add -> add_lock_to_list in __lock_acquire the lock_class is look up or registered from lockdep_map and put in held_lock, which is used in following function in call chain. Best Regards, Huang Ying