Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753483AbaBZRUh (ORCPT ); Wed, 26 Feb 2014 12:20:37 -0500 Received: from mail.efficios.com ([78.47.125.74]:42573 "EHLO mail.efficios.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752870AbaBZRUe (ORCPT ); Wed, 26 Feb 2014 12:20:34 -0500 Date: Wed, 26 Feb 2014 17:20:34 +0000 (UTC) From: Mathieu Desnoyers To: Steven Rostedt Cc: LKML , Ingo Molnar , Rusty Russell , Peter Zijlstra , Andrew Morton Message-ID: <118766423.31006.1393435234610.JavaMail.zimbra@efficios.com> In-Reply-To: <20140226110313.4d92fb83@gandalf.local.home> References: <20140226110313.4d92fb83@gandalf.local.home> Subject: Re: [RFC][PATCH] tracepoint: Do not waste memory on mods with no tracepoints MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [206.248.138.119] X-Mailer: Zimbra 8.0.5_GA_5839 (ZimbraWebClient - FF27 (Linux)/8.0.5_GA_5839) Thread-Topic: tracepoint: Do not waste memory on mods with no tracepoints Thread-Index: LTsaphPvdgIJ43Hd5uzripCXD0PlqQ== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ----- Original Message ----- > From: "Steven Rostedt" > To: "LKML" > Cc: "Ingo Molnar" , "Rusty Russell" , "Peter Zijlstra" > , "Mathieu Desnoyers" , "Andrew Morton" > > Sent: Wednesday, February 26, 2014 11:03:13 AM > Subject: [RFC][PATCH] tracepoint: Do not waste memory on mods with no tracepoints > > > No reason to allocate tp_module structures for modules that have no > tracepoints. This just wastes memory. Good catch! Thanks! Acked-by: Mathieu Desnoyers > > Fixes: b75ef8b44b1c "Tracepoint: Dissociate from module mutex" > Cc: stable@vger.kernel.org # 3.2+ > Cc: Mathieu Desnoyers > Signed-off-by: Steven Rostedt > --- > kernel/tracepoint.c | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/kernel/tracepoint.c b/kernel/tracepoint.c > index 29f2654..0d4ef26 100644 > --- a/kernel/tracepoint.c > +++ b/kernel/tracepoint.c > @@ -636,6 +636,9 @@ static int tracepoint_module_coming(struct module *mod) > struct tp_module *tp_mod, *iter; > int ret = 0; > > + if (!mod->num_tracepoints) > + return 0; > + > /* > * We skip modules that taint the kernel, especially those with different > * module headers (for forced load), to make sure we don't cause a crash. > @@ -679,6 +682,9 @@ static int tracepoint_module_going(struct module *mod) > { > struct tp_module *pos; > > + if (!mod->num_tracepoints) > + return 0; > + > mutex_lock(&tracepoints_mutex); > tracepoint_update_probe_range(mod->tracepoints_ptrs, > mod->tracepoints_ptrs + mod->num_tracepoints); > -- > 1.8.1.4 > > -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/