From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757725AbZEXUmu (ORCPT ); Sun, 24 May 2009 16:42:50 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751676AbZEXUmm (ORCPT ); Sun, 24 May 2009 16:42:42 -0400 Received: from mail-bw0-f174.google.com ([209.85.218.174]:36939 "EHLO mail-bw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751363AbZEXUml (ORCPT ); Sun, 24 May 2009 16:42:41 -0400 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=yIQ2a5jLpG+Zig6IChlYoRXEzwWXHC7kp3lec0lNAjUGRQBsi6JXZo3EcAToxvXhyd izI1V2lkjmkiHcbdyfD2D5RQ8D0biE+JlOBBtjzGwQO5R5U7bFur1pM2beQutI3hulnp uwxWF3M/l4oAxfU0aCwDUk/3v/y+ij5mxneZU= Date: Sun, 24 May 2009 22:42:43 +0200 From: Frederic Weisbecker To: Zhaolei Cc: Steven Rostedt , Ingo Molnar , Tom Zanussi , LKML Subject: Re: [PATCH v2 1/2] ftrace: Add task_comm support for trace_event Message-ID: <20090524204240.GB6471@nowhere> References: <4A14FDFE.2080402@cn.fujitsu.com> <4A16788F.2060802@cn.fujitsu.com> <4A1678F1.1060706@cn.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4A1678F1.1060706@cn.fujitsu.com> 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 Hi, On Fri, May 22, 2009 at 06:05:37PM +0800, Zhaolei wrote: > If we use trace_event alone(without function trace, .etc), > it can't output enough task command information. > > Before patch: > # echo 1 > debugfs/tracing/events/sched/sched_switch/enable > # cat debugfs/tracing/trace > # tracer: nop > # > # TASK-PID CPU# TIMESTAMP FUNCTION > # | | | | | > <...>-2289 [000] 526276.724790: sched_switch: task bash:2289 [120] ==> sshd:2287 [120] > <...>-2287 [000] 526276.725231: sched_switch: task sshd:2287 [120] ==> bash:2289 [120] > <...>-2289 [000] 526276.725452: sched_switch: task bash:2289 [120] ==> sshd:2287 [120] > <...>-2287 [000] 526276.727181: sched_switch: task sshd:2287 [120] ==> swapper:0 [140] > -0 [000] 526277.032734: sched_switch: task swapper:0 [140] ==> events/0:5 [115] > <...>-5 [000] 526277.032782: sched_switch: task events/0:5 [115] ==> swapper:0 [140] > ... > > After patch: > # tracer: nop > # > # TASK-PID CPU# TIMESTAMP FUNCTION > # | | | | | > bash-2269 [000] 527347.989229: sched_switch: task bash:2269 [120] ==> sshd:2267 [120] > sshd-2267 [000] 527347.990960: sched_switch: task sshd:2267 [120] ==> bash:2269 [120] > bash-2269 [000] 527347.991143: sched_switch: task bash:2269 [120] ==> sshd:2267 [120] > sshd-2267 [000] 527347.992959: sched_switch: task sshd:2267 [120] ==> swapper:0 [140] > -0 [000] 527348.531989: sched_switch: task swapper:0 [140] ==> events/0:5 [115] > events/0-5 [000] 527348.532115: sched_switch: task events/0:5 [115] ==> swapper:0 [140] > ... > > Signed-off-by: Zhao Lei Thanks! This is fine but I think it can be factorized. You could call start_cmdline_record() from ftrace_raw_reg_event_##call() and the stop in ftrace_raw_unreg_event_##call() No? Frederic. > --- > kernel/trace/Kconfig | 1 + > kernel/trace/trace_events.c | 6 ++++++ > 2 files changed, 7 insertions(+), 0 deletions(-) > > diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig > index f61be30..dffbb77 100644 > --- a/kernel/trace/Kconfig > +++ b/kernel/trace/Kconfig > @@ -187,6 +187,7 @@ config CONTEXT_SWITCH_TRACER > config ENABLE_EVENT_TRACING > bool "Trace various events in the kernel" > select TRACING > + select CONTEXT_SWITCH_TRACER > help > This tracer hooks to various trace points in the kernel > allowing the user to pick and choose which trace point they > diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c > index 0eec0c5..df35e5e 100644 > --- a/kernel/trace/trace_events.c > +++ b/kernel/trace/trace_events.c > @@ -85,6 +85,7 @@ static void ftrace_clear_events(void) > > if (call->enabled) { > call->enabled = 0; > + tracing_stop_cmdline_record(); > call->unregfunc(); > } > } > @@ -99,12 +100,14 @@ static void ftrace_event_enable_disable(struct ftrace_event_call *call, > case 0: > if (call->enabled) { > call->enabled = 0; > + tracing_stop_cmdline_record(); > call->unregfunc(); > } > break; > case 1: > if (!call->enabled) { > call->enabled = 1; > + tracing_start_cmdline_record(); > call->regfunc(); > } > break; > @@ -1058,6 +1061,7 @@ static void trace_module_remove_events(struct module *mod) > found = true; > if (call->enabled) { > call->enabled = 0; > + tracing_stop_cmdline_record(); > call->unregfunc(); > } > if (call->event) > @@ -1262,11 +1266,13 @@ static __init void event_trace_self_tests(void) > } > > call->enabled = 1; > + tracing_start_cmdline_record(); > call->regfunc(); > > event_test_stuff(); > > call->unregfunc(); > + tracing_stop_cmdline_record(); > call->enabled = 0; > > pr_cont("OK\n"); > -- > 1.5.5.3