Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753536Ab0AYOXf (ORCPT ); Mon, 25 Jan 2010 09:23:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752790Ab0AYOXe (ORCPT ); Mon, 25 Jan 2010 09:23:34 -0500 Received: from qw-out-2122.google.com ([74.125.92.26]:46525 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753423Ab0AYOXd (ORCPT ); Mon, 25 Jan 2010 09:23:33 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:cc:content-type; b=sqQ1CGY6Jk/Z62iMWZiX/2S3upFKBOw7YrsLj8ErS/oyA8pwpV+cCXhNTgLaOhYVKY DF5IlQPtZ195nKb9Y/l7UWH4vK0ksu33OpQhdKktgbv36W3/Vla+ICV91u0K/eRiWpoF EluvGaZVkFvfqKb+jsSd+pASSAdyCQrrp+l1E= MIME-Version: 1.0 In-Reply-To: <20100122164248.GA2651@redhat.com> References: <1264167553-6510-1-git-send-email-mitake@dcl.info.waseda.ac.jp> <20100122164248.GA2651@redhat.com> Date: Mon, 25 Jan 2010 23:15:33 +0900 X-Google-Sender-Auth: aa44257e972fb78e Message-ID: Subject: Re: [PATCH 00/12] perf lock: New subcommand "perf lock", for analyzing lock statistics From: Hitoshi Mitake To: Jason Baron Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Peter Zijlstra , Paul Mackerras , Tom Zanussi , Steven Rostedt , Thomas Gleixner , Greg Kroah-Hartman Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1453 Lines: 36 Hi Jason, thanks for your reply! On Sat, Jan 23, 2010 at 01:42, Jason Baron wrote: > On Fri, Jan 22, 2010 at 10:39:01PM +0900, Hitoshi Mitake wrote: >> Adding new subcommand "perf lock" to perf. >> > > looks like a really intresting patch! Does this patch mean that we can > potentially remove CONFIG_LOCK_STAT, now that the functionality is > available via 'perf'? Another desire for me has been to able to run > lockstat on production box. This has not been possible before without > incurring the performance penalty of lockdep. however, with 'perf' tools > ability to be turned on an off, perhaps there is (or we can build) a > mode for lockdep that is lower overhead for this usecase? > As Peter told, this patch series depends on lockdep. But, checking dependency and tracing lock events are essentially different things. So I think dividing these is possible. But, perf depends on debugfs. I don't know about production box well, does your production box turns on debugfs? It seems that debugfs is not a thing for production box... And I'm interesting in in-kernel histogram of locks. Is there requirement of it? I have some ideas (not done yet, completely). Thanks, Hitoshi -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/