From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756388Ab3GLDFt (ORCPT ); Thu, 11 Jul 2013 23:05:49 -0400 Received: from intranet.asianux.com ([58.214.24.6]:11565 "EHLO intranet.asianux.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754371Ab3GLDFs (ORCPT ); Thu, 11 Jul 2013 23:05:48 -0400 X-Spam-Score: -100.8 Message-ID: <51DF7250.9020209@asianux.com> Date: Fri, 12 Jul 2013 11:04:48 +0800 From: Chen Gang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Steven Rostedt CC: Frederic Weisbecker , "mingo@redhat.com" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH] kernel: trace: remove __init from race_selftest_startup_function() and trace_selftest_startup_function_graph() References: <51DDFCF8.2090808@asianux.com> <1373561279.17876.45.camel@gandalf.local.home> <51DF44FA.9060000@asianux.com> <1373593261.17876.61.camel@gandalf.local.home> <51DF62DB.3010409@asianux.com> <1373596735.17876.84.camel@gandalf.local.home> In-Reply-To: <1373596735.17876.84.camel@gandalf.local.home> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/12/2013 10:38 AM, Steven Rostedt wrote: > On Fri, 2013-07-12 at 09:58 +0800, Chen Gang wrote: >> On 07/12/2013 09:41 AM, Steven Rostedt wrote: >>> On Fri, 2013-07-12 at 07:51 +0800, Chen Gang wrote: >>> >>>>> Hmm, can all trace_selftest_startup_* (*selftest* in trace_selftest.c) >>>>> use '__init', so not waste memory keeping them around ? >>> Yeah, they should all be set to __init, but that's pretty low on the >>> totem poll, as distros don't enable selftests in their main kernels. >> >> Excuse me, my English is not quite well, I guess your meaning is: >> >> they should all be set to '__init', although it is minor in real world. >> >> Is it correct ? > > Correct. > >> >> >> For me, I recommend to let all *selftest* as the same: "all add ' >> __init' or none add '__init'" (if choose add, all report warnings). >> >> Is it suitable to still send new related patch for it ? If so, could >> you provide your suggesting choice (all add, or none add) ? > > Does this patch fix your warning? > > -- Steve > I guess it can (although I do not give a compiling test), it seems a better fixing. And is it suitable to let all *selftest* as the same ? (all add, or none add '__init'). Thanks. > diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h > index a4ed382..5e794d1 100644 > --- a/kernel/trace/trace.h > +++ b/kernel/trace/trace.h > @@ -680,6 +680,15 @@ extern int trace_selftest_startup_sched_switch(struct tracer *trace, > struct trace_array *tr); > extern int trace_selftest_startup_branch(struct tracer *trace, > struct trace_array *tr); > +/* > + * Tracer data references selftest functions that only occur > + * on boot up. These can be __init functions. Thus, when selftests > + * are enabled, then the tracers need to reference __init functions. > + */ > +#define __tracer_data __refdata > +#else > +/* Tracers are seldom changed. Optimize when selftests are disabled. */ > +#define __tracer_data __read_mostly > #endif /* CONFIG_FTRACE_STARTUP_TEST */ > > extern void *head_page(struct trace_array_cpu *data); > diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c > index b863f93..38fe148 100644 > --- a/kernel/trace/trace_functions.c > +++ b/kernel/trace/trace_functions.c > @@ -199,7 +199,7 @@ static int func_set_flag(u32 old_flags, u32 bit, int set) > return 0; > } > > -static struct tracer function_trace __read_mostly = > +static struct tracer function_trace __tracer_data = > { > .name = "function", > .init = function_trace_init, > > > > -- Chen Gang