From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757134Ab0ANPIq (ORCPT ); Thu, 14 Jan 2010 10:08:46 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S932248Ab0ANPHK (ORCPT ); Thu, 14 Jan 2010 10:07:10 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.124]:41287 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756905Ab0ANPGw (ORCPT ); Thu, 14 Jan 2010 10:06:52 -0500 X-Authority-Analysis: v=1.0 c=1 a=Nora_UQfvSMA:10 a=7U3hwN5JcxgA:10 a=pGLkceISAAAA:8 a=meVymXHHAAAA:8 a=omOdbC7AAAAA:8 a=VnNF1IyMAAAA:8 a=rzlYJIk-HrhOc_vsxusA:9 a=RkMuDUgsPLePwPGYVSm6vhM3HMsA:4 a=MSl-tDqOz04A:10 a=jeBq3FmKZ4MA:10 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.89.75 Subject: Re: [PATCH] tracing: Drop the tr check from the graph tracing path From: Steven Rostedt Reply-To: rostedt@goodmis.org To: Frederic Weisbecker Cc: Ingo Molnar , LKML , Lai Jiangshan , "Paul E. McKenney" In-Reply-To: <1263453795-7496-1-git-send-regression-fweisbec@gmail.com> References: <1263453795-7496-1-git-send-regression-fweisbec@gmail.com> Content-Type: text/plain; charset="ISO-8859-15" Organization: Kihon Technologies Inc. Date: Thu, 14 Jan 2010 10:06:49 -0500 Message-ID: <1263481609.28171.3845.camel@gandalf.stny.rr.com> Mime-Version: 1.0 X-Mailer: Evolution 2.28.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2010-01-14 at 08:23 +0100, Frederic Weisbecker wrote: > Each time we save a function entry from the function graph tracer, > we check if the trace array is set, which is wasteful because it is > set anyway before we start the tracer. All we need is to ensure we > have good read and write orderings. When we set the trace array, we > just need to guarantee it to be visible before starting tracing. > > Signed-off-by: Frederic Weisbecker Acked-by: Steven Rostedt -- Steve > Cc: Lai Jiangshan > Cc: Paul E. McKenney > --- > kernel/trace/trace_functions_graph.c | 19 ++++++++++--------- > 1 files changed, 10 insertions(+), 9 deletions(-)