From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758018Ab0JUNdv (ORCPT ); Thu, 21 Oct 2010 09:33:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:3589 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755941Ab0JUNdu (ORCPT ); Thu, 21 Oct 2010 09:33:50 -0400 Subject: Re: Ftrace: can trace kthread? From: Steven Rostedt To: "Figo.zhang" Cc: Li Zefan , "linux-kernel@vger.kernel.org" In-Reply-To: <1287647732.2237.7.camel@myhost> References: <1287647732.2237.7.camel@myhost> Content-Type: text/plain; charset="UTF-8" Organization: Red Hat Date: Thu, 21 Oct 2010 09:33:43 -0400 Message-ID: <1287668023.2824.15.camel@fedora> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Just a quick note. Please send email to my rostedt@goodmis.org address. I do not check my srostedt@redhat.com address as often. I know, I know, I have it as my Author tag (but not my signed off by) and I had to add it to my business card. I just could not be so bold as to put my goodmis.org address on my Red Hat business card ;-) And there was no good way to add it as a secondary. -- Steve On Thu, 2010-10-21 at 15:55 +0800, Figo.zhang wrote: > hi, > > is it ftrace in 2.6.36-rc8 can trace the kthread? i want to trace the > kswapd/bdi_writeback_thread, but not success. i am sure that kswapd is > running, because i let the system eat huge memory. i can trace some > function such as __do_fault. what is issue on it? > > Best, > Figo.zhang > > > here is my ftrace script. > i = 1 > while true; > do > echo 1 > /proc/sys/kernel/ftrace_enabled > echo function_graph > /sys/kernel/debug/tracing/current_tracer > echo kswapd > /sys/kernel/debug/tracing/set_graph_function > echo 1 > /sys/kernel/debug/tracing/tracing_on > echo 1 > /sys/kernel/debug/tracing/tracing_enabled > sleep 1 > echo 0 > /sys/kernel/debug/tracing/tracing_enabled > cat /sys/kernel/debug/tracing/trace > ftrace.kswap.log.$i > > let i=i+1; > > done > > >