From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755306AbYJEJxq (ORCPT ); Sun, 5 Oct 2008 05:53:46 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753253AbYJEJxi (ORCPT ); Sun, 5 Oct 2008 05:53:38 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:48921 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753205AbYJEJxi (ORCPT ); Sun, 5 Oct 2008 05:53:38 -0400 Date: Sun, 5 Oct 2008 11:53:26 +0200 From: Ingo Molnar To: Steven Rostedt Cc: Arjan van de Ven , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] ftrace: Add a C-state tracer to help power optimization Message-ID: <20081005095326.GD29909@elte.hu> References: <20081004105447.0e48d6d4@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Steven Rostedt wrote: > > My comments are more towards Ingo than to Arjan. > > On Sat, 4 Oct 2008, Arjan van de Ven wrote: > > +++ b/kernel/trace/Kconfig > > @@ -134,6 +134,17 @@ config BOOT_TRACER > > be enabled if this tracer is selected since only one tracer > > should touch the tracing buffer at a time. > > > > +config CSTATE_TRACER > > + bool "Trace C-state behavior" > > + depends on HAVE_FTRACE > > Ingo, here's the confusion again between the FTRACE infrastructure and > the ftrace "function tracer". the HAVE_FTRACE should really be > HAVE_FUNCTION_TRACER. The infrastructure of a lot of the ftrace > tracers do not depend on the function tracer. > > The CSTATE_TRACER also does not depend on HAVE_FTRACE. Think we should > rename this? Otherwise more kernel developers will get confused by it. > :-( agreed, please send a rename patch to make it more consistent. > > +static enum print_line_t cstate_print_line(struct trace_iterator *iter) > > +{ > > + int ret; > > + struct trace_entry *entry = iter->ent; > > + struct trace_cstate *field = (struct trace_cstate *)entry; > > Ingo, isn't the trace_assign_type in your latest tree? yeah, it is, and it should be used here instead of a direct cast. Ingo