From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752227AbcGGKX4 (ORCPT ); Thu, 7 Jul 2016 06:23:56 -0400 Received: from LGEAMRELO11.lge.com ([156.147.23.51]:39258 "EHLO lgeamrelo11.lge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751560AbcGGKXy (ORCPT ); Thu, 7 Jul 2016 06:23:54 -0400 X-Original-SENDERIP: 156.147.1.121 X-Original-MAILFROM: byungchul.park@lge.com X-Original-SENDERIP: 10.177.222.33 X-Original-MAILFROM: byungchul.park@lge.com Date: Thu, 7 Jul 2016 19:22:06 +0900 From: Byungchul Park To: Peter Zijlstra Cc: mingo@kernel.org, linux-kernel@vger.kernel.org, npiggin@suse.de, sergey.senozhatsky@gmail.com, gregkh@linuxfoundation.org, minchan@kernel.org Subject: Re: [PATCH 1/5] lockdep: Implement bitlock map allocator Message-ID: <20160707102206.GG2279@X58A-UD3R> References: <1466398515-1005-1-git-send-email-byungchul.park@lge.com> <1466398515-1005-2-git-send-email-byungchul.park@lge.com> <20160630125919.GD30154@twins.programming.kicks-ass.net> <20160701002444.GV2279@X58A-UD3R> <20160701075312.GL30921@twins.programming.kicks-ass.net> <20160704072925.GY2279@X58A-UD3R> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160704072925.GY2279@X58A-UD3R> 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 On Mon, Jul 04, 2016 at 04:29:25PM +0900, Byungchul Park wrote: > > > 3. I think this is more general approach because _any_ random bit in > > > memory can be used as a lock. Do we need to restrict where the bit > > > is so that we can place lockdep_map explicitly around the bit? > > > > Again, yuck! > > You mean we should never provide lockdep checking mechanism tranparently, > but the user of bit-based lock must add lockdep_map manually, case by > case. Right? Do I understand correctly? If so, I wonder why? I will stop it if it cannot provide any valuable things even I wonder. I seriously asked it since I wonder it. What do you think about my question? Is there something I missed? Or can I proceed it after fixing my bug you pointed?