Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753991AbZI3ICW (ORCPT ); Wed, 30 Sep 2009 04:02:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753432AbZI3ICU (ORCPT ); Wed, 30 Sep 2009 04:02:20 -0400 Received: from mail09.linbit.com ([212.69.161.110]:51131 "EHLO mail09.linbit.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753527AbZI3ICS (ORCPT ); Wed, 30 Sep 2009 04:02:18 -0400 Date: Wed, 30 Sep 2009 10:02:21 +0200 From: Lars Ellenberg To: Christoph Hellwig Cc: Philipp Reisner , Randy Dunlap , Stephen Rothwell , LKML , linux-next@vger.kernel.org, akpm , drbd-dev@lists.linbit.com Subject: Re: [Drbd-dev] [PATCH -next] drbd: trace depends on TRACING Message-ID: <20090930080221.GA8032@barkeeper1-xen.linbit> Mail-Followup-To: Christoph Hellwig , Philipp Reisner , Randy Dunlap , Stephen Rothwell , LKML , linux-next@vger.kernel.org, akpm , drbd-dev@lists.linbit.com References: <20090925133830.1ba29584.sfr@canb.auug.org.au> <4ABD4C28.9070202@oracle.com> <200909291732.51383.philipp.reisner@linbit.com> <20090929153747.GA29621@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20090929153747.GA29621@infradead.org> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1694 Lines: 44 On Tue, Sep 29, 2009 at 11:37:47AM -0400, Christoph Hellwig wrote: > On Tue, Sep 29, 2009 at 05:32:50PM +0200, Philipp Reisner wrote: > > On Saturday 26 September 2009 01:03:04 Randy Dunlap wrote: > > > From: Randy Dunlap > > > > > > DRBD_TRACE should depend on TRACING. > > > It's also possible that TRACEPOINTS should depend on TRACING. > > > > > > > Hi Randy, > > > > I tried to figure out in which way that should be done. By looking > > at "BLK_DEV_IO_TRACE" I got the impression that this should > > be done by adding "select GENERIC_TRACER". > > Neither really. The only way of tracing that should be used is the > TRACE_EVENT macros, which compile away to nothing if tracing is > disabled, so no dependency is needed at all. TRACE_EVENT macros depend on, and use TRACE_POINTS. And those trace points are what compiles away if !CONFIG_TRACEPOINTS, no? kernel/trace/Kconfig says # All tracer options should select GENERIC_TRACER. [...] If one uses tracepoints without trace_events, they still compile away. If using tracepoints directly, not using the (admittedly elegant) trace-events macro system, is in fact not wanted anymore, then Documentation/trace/* should be changed accordingly. So what is the plan, going forward? -- : Lars Ellenberg : LINBIT | Your Way to High Availability : DRBD/HA support and consulting http://www.linbit.com DRBD? and LINBIT? are registered trademarks of LINBIT, Austria. -- 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/