From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754231AbaGKPMp (ORCPT ); Fri, 11 Jul 2014 11:12:45 -0400 Received: from e37.co.us.ibm.com ([32.97.110.158]:49799 "EHLO e37.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752613AbaGKPMo (ORCPT ); Fri, 11 Jul 2014 11:12:44 -0400 Date: Fri, 11 Jul 2014 08:12:40 -0700 From: "Paul E. McKenney" To: Ard Biesheuvel Cc: linux-kernel@vger.kernel.org, rostedt@goodmis.org, dipankar@in.ibm.com Subject: Re: [PATCH] rcu: define tracepoint strings only if CONFIG_TRACING is set Message-ID: <20140711151239.GJ16041@linux.vnet.ibm.com> Reply-To: paulmck@linux.vnet.ibm.com References: <1405078692-29957-1-git-send-email-ard.biesheuvel@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1405078692-29957-1-git-send-email-ard.biesheuvel@linaro.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 14071115-7164-0000-0000-000003106BB6 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 11, 2014 at 01:38:12PM +0200, Ard Biesheuvel wrote: > Commit f7f7bac9cb1c ("rcu: Have the RCU tracepoints use the tracepoint_string > infrastructure") unconditionally populates the __tracepoint_str input section, > but this section is not assigned an output section if CONFIG_TRACING is not set. > This results in the __tracepoint_str turning up in unexpected places, i.e., > after _edata. > > Signed-off-by: Ard Biesheuvel > Cc: rostedt@goodmis.org > Cc: dipankar@in.ibm.com > Cc: paulmck@linux.vnet.ibm.com If you get a Reviewed-by from Steven Rostedt, I will be happy to queue this one. Thanx, Paul > --- > kernel/rcu/tree.c | 9 ++++++++- > 1 file changed, 8 insertions(+), 1 deletion(-) > > diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c > index f1ba77363fbb..ac1984149eb5 100644 > --- a/kernel/rcu/tree.c > +++ b/kernel/rcu/tree.c > @@ -79,9 +79,16 @@ static struct lock_class_key rcu_fqs_class[RCU_NUM_LVLS]; > * the tracing userspace tools to be able to decipher the string > * address to the matching string. > */ > +#ifdef CONFIG_TRACING > +#define DEFINE_TPS(sname) \ > +static const char *tp_##sname##_varname __used __tracepoint_string = sname##_varname; > +#else > +#define DEFINE_TPS(sname) > +#endif > + > #define RCU_STATE_INITIALIZER(sname, sabbr, cr) \ > static char sname##_varname[] = #sname; \ > -static const char *tp_##sname##_varname __used __tracepoint_string = sname##_varname; \ > +DEFINE_TPS(sname) \ > struct rcu_state sname##_state = { \ > .level = { &sname##_state.node[0] }, \ > .call = cr, \ > -- > 1.8.3.2 >