Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760661AbXEUTSD (ORCPT ); Mon, 21 May 2007 15:18:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757133AbXEUTRy (ORCPT ); Mon, 21 May 2007 15:17:54 -0400 Received: from adsl-69-232-92-238.dsl.sndg02.pacbell.net ([69.232.92.238]:35663 "EHLO gnuppy.monkey.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757037AbXEUTRx (ORCPT ); Mon, 21 May 2007 15:17:53 -0400 Date: Mon, 21 May 2007 12:17:21 -0700 To: Ingo Molnar Cc: Christoph Hellwig , Peter Zijlstra , linux-kernel@vger.kernel.org, Jason Baron , Steven Rostedt , "Bill Huey (hui)" Subject: Re: [PATCH] lockdep: lock contention tracking Message-ID: <20070521191721.GD4442@gnuppy.monkey.org> References: <1179657026.5915.10.camel@lappy> <20070521060446.GA4593@gnuppy.monkey.org> <20070521060828.GB20277@elte.hu> <20070521064150.GC4442@gnuppy.monkey.org> <20070521075013.GA9419@elte.hu> <20070521091848.GB4593@gnuppy.monkey.org> <20070521093639.GA29025@elte.hu> <20070521095547.GA10697@infradead.org> <20070521105803.GA17096@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20070521105803.GA17096@elte.hu> User-Agent: Mutt/1.5.13 (2006-08-11) From: Bill Huey (hui) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1152 Lines: 24 On Mon, May 21, 2007 at 12:58:03PM +0200, Ingo Molnar wrote: > and nobody pushed strong enough to get it included. But ... Peter's > patch could perhaps be extended to cover similar stats as lockmeter, > ontop of the existing lockdep instrumentation. Peter, can you see any > particular roadblocks with that? Definitely. Lockmeter isn't terribly Linux-ish from my examination of that patch a while back. Doing it against lockdep is definitely the right thing to do in that it unifies lock handling through initializer keys that lockmeter doesn't, from my memory. The spin time tracking can be put into the slow path of the spin, like what peter has now, so that it has minimal impact against the uncontended case. Updating the times would then be a trivial pointer dereference plus add and hopefully won't have instrumentation side effects against the rest of the locking behavior in the system. bill - 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/