From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755036AbYJFQ5c (ORCPT ); Mon, 6 Oct 2008 12:57:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753253AbYJFQ5Z (ORCPT ); Mon, 6 Oct 2008 12:57:25 -0400 Received: from casper.infradead.org ([85.118.1.10]:52970 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753177AbYJFQ5Y (ORCPT ); Mon, 6 Oct 2008 12:57:24 -0400 Date: Mon, 6 Oct 2008 09:57:07 -0700 From: Arjan van de Ven To: Peter Zijlstra Cc: Steven Rostedt , mingo@elte.hu, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] ftrace: Add a C-state tracer to help power optimization Message-ID: <20081006095707.0c1b5a23@infradead.org> In-Reply-To: <1223311960.12409.28.camel@lappy.programming.kicks-ass.net> References: <20081004105447.0e48d6d4@infradead.org> <20081004112915.7c2b45ea@infradead.org> <1223311960.12409.28.camel@lappy.programming.kicks-ass.net> Organization: Intel X-Mailer: Claws Mail 3.5.0 (GTK+ 2.12.12; i386-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-SRS-Rewrite: SMTP reverse-path rewritten from by casper.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 06 Oct 2008 18:52:39 +0200 Peter Zijlstra wrote: > > > > > > #endif /* _LINUX_FTRACE_H */ > > Why have the cstate_trace structure? If you just log start, stop you > could compute the time delta from the trace time stamps, no? there's 2 other fields I need than just the timestamp. > > If you decide to keep the structure, perhaps declare it empty for ! > CONFIG_CSTATE_TRACER so as to not bloat stack usage when its not > configured. ok good point > -- Arjan van de Ven Intel Open Source Technology Centre For development, discussion and tips for power savings, visit http://www.lesswatts.org