From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755468AbZCVRDt (ORCPT ); Sun, 22 Mar 2009 13:03:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754639AbZCVRDk (ORCPT ); Sun, 22 Mar 2009 13:03:40 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:38456 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752430AbZCVRDj (ORCPT ); Sun, 22 Mar 2009 13:03:39 -0400 Date: Sun, 22 Mar 2009 18:03:33 +0100 From: Ingo Molnar To: Frederic Weisbecker Cc: Steven Rostedt , LKML Subject: Re: [PATCH] tracing/function-graph-tracer: don't profile branches on graph tracer Message-ID: <20090322170333.GA6936@elte.hu> References: <1237741289-14926-1-git-send-email-fweisbec@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1237741289-14926-1-git-send-email-fweisbec@gmail.com> 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=3.2.5 -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 * Frederic Weisbecker wrote: > Impact: fix slow tracing > > The core kernel tracing is protected against soft branch > profiling, but not the x86 ftrace arch part. Let's fix it. right now we should simply disable the branch profiler if any function tracing variant is enabled. We should probably mark it CONFIG_BROKEN until it's properly per-cpu-ized. Ingo