Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756849AbZKBVnw (ORCPT ); Mon, 2 Nov 2009 16:43:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756770AbZKBVnw (ORCPT ); Mon, 2 Nov 2009 16:43:52 -0500 Received: from ey-out-2122.google.com ([74.125.78.24]:59631 "EHLO ey-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756313AbZKBVnv (ORCPT ); Mon, 2 Nov 2009 16:43:51 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=F6wh4sZinmOFvy2YheS+kAVAzANDnMjvIFqg10SQatyZDqepDolyEHYTCCY8efeG7d GqQfspsrpK+biSmcbcm0Sf5amsIJq08/i+rzoFaah8/ViTMi7dFXnu6VGIEVQh0EGjPp kL3OVI476Xboa19AjxzX2zHkfJ3D1orJOd3ls= Date: Mon, 2 Nov 2009 22:43:55 +0100 From: Frederic Weisbecker To: Wu Zhangjin Cc: linux-mips@linux-mips.org, linux-kernel@vger.kernel.org, rostedt@goodmis.org, Thomas Gleixner , Ralf Baechle , Nicholas Mc Guire , Richard Sandiford , David Daney , Adam Nemet , Patrik Kluba Subject: Re: [PATCH -v5 08/11] tracing: not trace mips_timecounter_init() in MIPS Message-ID: <20091102214351.GI4880@nowhere> References: <2f73eae542c47ac5bbb9f7280e6c0271d193e90d.1256483735.git.wuzhangjin@gmail.com> <3e0c2d7d8b8f196a8153beb41ea7f3cbf42b3d84.1256483735.git.wuzhangjin@gmail.com> <54c417629e91f40b2bbb4e08cda2a4e6527824c0.1256483735.git.wuzhangjin@gmail.com> <29bccff04932e993ecd9f516d8b6dcf84e2ceecf.1256483735.git.wuzhangjin@gmail.com> <72f2270f7b6e01ca7a4cdf4ac8c21778e5d9652f.1256483735.git.wuzhangjin@gmail.com> <6140dd8f4e1783e5ac30977cf008bb98e4698322.1256483735.git.wuzhangjin@gmail.com> <49b3c441a57f4db423732f81432a3450ccb3240e.1256483735.git.wuzhangjin@gmail.com> <1256550156.5642.148.camel@falcon> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1256550156.5642.148.camel@falcon> 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: 2184 Lines: 58 On Mon, Oct 26, 2009 at 05:42:36PM +0800, Wu Zhangjin wrote: > On Mon, 2009-10-26 at 01:27 +0100, Frederic Weisbecker wrote: > > 2009/10/25 Wu Zhangjin : > > > -static inline u64 mips_timecounter_read(void) > > > +static inline u64 notrace mips_timecounter_read(void) > > > > > > You don't need to set notrace functions, unless their addresses > > are referenced somewhere, which unfortunately might happen > > for some functions but this is rare. > > > > Okay, Will remove it. Oops, a word has escaped from my above sentence. I wanted to say: "You don't need to set notrace to inline functions" :) > > Hmm yeah this is not very nice to do that in core functions because > > of a specific arch problem. > > At least you have __notrace_funcgraph, this is a notrace > > that only applies if CONFIG_FUNCTION_GRAPH_TRACER > > so that it's still traceable by the function tracer in this case. > > > > But I would rather see a __mips_notrace on these two core functions. > > What about this: __arch_notrace? If the arch need this, define it, > otherwise, ignore it! if only graph tracer need it, define it in "#ifdef > CONFIG_FUNCTION_GRAPH_TRACER ... #endif". The problem is that archs may want to disable tracing on different places. For example mips wants to disable tracing in timecounter_read_delta, but another arch may want to disable tracing somewhere else. We'll then have several unrelated __arch_notrace. One that is relevant for mips, another that is relevant for arch_foo, but all of them will apply for all arch that have defined a __arch_notrace. It's true that __mips_notrace is not very elegant as it looks like a specific arch annotation intruder. But at least that gives us a per arch filter granularity. If only static ftrace could disappear, we could keep only dynamic ftrace and we would then be able to filter dynamically. But I'm not sure it's a good idea for archs integration. -- 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/