From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758614AbYLFDB7 (ORCPT ); Fri, 5 Dec 2008 22:01:59 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755122AbYLFDBu (ORCPT ); Fri, 5 Dec 2008 22:01:50 -0500 Received: from fg-out-1718.google.com ([72.14.220.157]:9793 "EHLO fg-out-1718.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755044AbYLFDBt (ORCPT ); Fri, 5 Dec 2008 22:01:49 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; b=M2WlzWzDujja+zPHO1Q0G8m+Bb6PCycxZCDB8g2lKN6UlcLy2ta1J7uaJiW4KuMjG3 iMMbq3Y/Ge66iIRqlgU+KbZHycEtEd9/bpfTGQnOAAC7r5QjC7Zsme7vcWBDjO6vY+LG o7DgkPLNWCMUKAn19my1O1e4b8KRx6u/6hJro= Message-ID: <4939EB18.6090606@gmail.com> Date: Sat, 06 Dec 2008 04:01:44 +0100 From: Frederic Weisbecker User-Agent: Thunderbird 2.0.0.18 (X11/20081125) MIME-Version: 1.0 To: Ingo Molnar CC: Steven Rostedt , Linux Kernel Subject: Re: [PATCH 1/3] tracing/function-graph-tracer: introduce __notrace_funcgraph to filter special functions References: <4939E600.804@gmail.com> In-Reply-To: <4939E600.804@gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Frederic Weisbecker wrote: > Impact: trace more functions > > When the function graph tracer is configured, three more files are not traced to prevent > only four functions to be traced. And this impacts the normal function tracer too. > > arch/x86/kernel/process_64/32.c: > > I had crashes when I let this file traced. After some debugging, I saw that > the "current" task point was changed inside__swtich_to(), ie: "write_pda(pcurrent, next_p);" > inside process_64.c > Since the tracer store the original return address of the function inside current, we had crashes. > Only __switch_to() has to be traced. > > kernel/module.c and kernel/extable.c: > > Because of a function used internally by the function graph tracer: __kernel_text_address() > > To let the other functions inside these files to be traced, this patch introduces the > __notrace_funcgraph function prefix which is __notrace if function graph tracer is > configured and nothing if not. > And once again I...did not test under x86-32 :-s