From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753668Ab3F0JG0 (ORCPT ); Thu, 27 Jun 2013 05:06:26 -0400 Received: from mail-ea0-f175.google.com ([209.85.215.175]:37901 "EHLO mail-ea0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752781Ab3F0JF5 (ORCPT ); Thu, 27 Jun 2013 05:05:57 -0400 Date: Thu, 27 Jun 2013 11:05:52 +0200 From: Ingo Molnar To: Sasha Levin Cc: Peter Zijlstra , torvalds@linux-foundation.org, linux-kernel@vger.kernel.org Subject: Re: [Patch v5 0/9] liblockdep: userspace lockdep Message-ID: <20130627090552.GB4398@gmail.com> References: <1371163284-6346-1-git-send-email-sasha.levin@oracle.com> <20130626122408.GJ28407@twins.programming.kicks-ass.net> <20130626155325.GB7399@gmail.com> <51CB4328.7010006@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <51CB4328.7010006@oracle.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 * Sasha Levin wrote: > On 06/26/2013 11:53 AM, Ingo Molnar wrote: > >>Ingo, I don't think I see anything holding this back; however I remember > >>>reading some email about people not liking stuff like this living in the > >>>tools/ directory or such. > >>> > >>>Will you pick this up? > >So I'd really be interested in how interesting/useful this is to userspace > >developers? Does it work for something complex as Firefox, or Apache, to > >the extent they make use of these locking APIs? > > So far I've tested it on Firefox, Apache, QEMU, LKVM, GCC and random > smallish programs. I haven't really done full testing for each of those, > but just made sure that liblockdep behaves as it supposed to. I'm > guessing that with further work it will dig up actual issues. Would it be possible to collect and print some stats about lock API usages, a'ka /proc/lockdep_stats et al? Also, Xorg might be something that uses rather involved locking. It might not use many pthread mutexes though. Thanks, Ingo