From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759626AbcAUO0D (ORCPT ); Thu, 21 Jan 2016 09:26:03 -0500 Received: from mail.kernel.org ([198.145.29.136]:39222 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759175AbcAUOZ7 (ORCPT ); Thu, 21 Jan 2016 09:25:59 -0500 Date: Thu, 21 Jan 2016 11:25:54 -0300 From: Arnaldo Carvalho de Melo To: Ben Hutchings Cc: Peter Zijlstra , Ingo Molnar , linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH RESEND] perf: Document the perf sysctls Message-ID: <20160121142554.GC2312@kernel.org> References: <20160111151958.GQ28542@decadent.org.uk> <20160119213515.GG2637@decadent.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20160119213515.GG2637@decadent.org.uk> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Tue, Jan 19, 2016 at 09:35:15PM +0000, Ben Hutchings escreveu: > perf_event_paranoid was only documented in source code and a perf > error message. Move the documentation from the error message to > Documentation/sysctl/kernel.txt. > > perf_cpu_time_max_percent was already documented but missing from the > list at the top, so add it there. > > Signed-off-by: Ben Hutchings > --- > Documentation/sysctl/kernel.txt | 13 +++++++++++++ > tools/perf/util/evsel.c | 7 ++----- > 2 files changed, 15 insertions(+), 5 deletions(-) > > diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt > index af70d15..88a2c8e 100644 > --- a/Documentation/sysctl/kernel.txt > +++ b/Documentation/sysctl/kernel.txt > @@ -58,6 +58,8 @@ show up in /proc/sys/kernel: > - panic_on_stackoverflow > - panic_on_unrecovered_nmi > - panic_on_warn > +- perf_cpu_time_max_percent > +- perf_event_paranoid > - pid_max > - powersave-nap [ PPC only ] > - printk > @@ -624,6 +626,17 @@ allowed to execute. > > ============================================================== > > +perf_event_paranoid: > + > +Controls use of the performance events system by unprivileged > +users (without CAP_SYS_ADMIN). The default value is 1. > + > + -1: Allow use of (almost) all events by all users > +>=0: Disallow raw tracepoint access by users without CAP_IOC_LOCK > +>=1: Disallow CPU event access by users without CAP_SYS_ADMIN > +>=2: Disallow kernel profiling by users without CAP_SYS_ADMIN > + > +============================================================== > > pid_max: > > diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c > index 397fb4e..9b4df11 100644 > --- a/tools/perf/util/evsel.c > +++ b/tools/perf/util/evsel.c > @@ -2314,11 +2314,8 @@ int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target, > case EACCES: > return scnprintf(msg, size, > "You may not have permission to collect %sstats.\n" > - "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n" > - " -1 - Not paranoid at all\n" > - " 0 - Disallow raw tracepoint access for unpriv\n" > - " 1 - Disallow cpu events for unpriv\n" > - " 2 - Disallow kernel profiling for unpriv", > + "Consider tweaking /proc/sys/kernel/perf_event_paranoid -\n" > + "see Documentation/sysctl/kernel.txt", > target->system_wide ? "system-wide " : ""); Don't remove readily available information by a reference to a not always available file, I'm just synching this with the doc text you added to that Documentation file. - Arnaldo > case ENOENT: > return scnprintf(msg, size, "The %s event is not supported.", >