From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [PATCH] perf tools: Clarify error when running "perf lock record" Date: Thu, 05 Sep 2013 08:29:10 -0600 Message-ID: <52289536.3070504@gmail.com> References: <1378369936-26473-1-git-send-email-rodrigo@sdfg.com.ar> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-pb0-f48.google.com ([209.85.160.48]:62778 "EHLO mail-pb0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752650Ab3IEO3Q (ORCPT ); Thu, 5 Sep 2013 10:29:16 -0400 In-Reply-To: <1378369936-26473-1-git-send-email-rodrigo@sdfg.com.ar> Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: Rodrigo Campos Cc: linux-kernel@vger.kernel.org, a.p.zijlstra@chello.nl, paulus@samba.org, mingo@redhat.com, acme@ghostprotocols.net, linux-perf-users@vger.kernel.org On 9/5/13 2:32 AM, Rodrigo Campos wrote: > If you have the config options enabled in your kernel, you still need to be root > to run perf lock. And is kind of misleading when you have that options enabled > and the error says that they might not be. > > So, this patch just adds to the error that it should be run as root. Although we > can probably check if it's running as root or not, adding it to the error > message is really simple and should be enough. > > Signed-off-by: Rodrigo Campos > --- > Please keep me in Cc: since I'm not subscribed > --- > tools/perf/builtin-lock.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/tools/perf/builtin-lock.c b/tools/perf/builtin-lock.c > index 76543a4..f07b318 100644 > --- a/tools/perf/builtin-lock.c > +++ b/tools/perf/builtin-lock.c > @@ -886,8 +886,8 @@ static int __cmd_record(int argc, const char **argv) > for (i = 0; i < ARRAY_SIZE(lock_tracepoints); i++) { > if (!is_valid_tracepoint(lock_tracepoints[i].name)) { > pr_err("tracepoint %s is not enabled. " > - "Are CONFIG_LOCKDEP and CONFIG_LOCK_STAT enabled?\n", > - lock_tracepoints[i].name); > + "Are CONFIG_LOCKDEP and CONFIG_LOCK_STAT enabled " > + "and running as root?\n", lock_tracepoints[i].name); > return 1; > } > } > you can run perf-lock as non-root with certain settings. It would be better to discriminate debugfs access errors (insufficient privilege). That means improving is_valid_tracepoint and handling the errors in perf-lock. David