Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754042Ab3H1Nia (ORCPT ); Wed, 28 Aug 2013 09:38:30 -0400 Received: from mail-oa0-f53.google.com ([209.85.219.53]:36890 "EHLO mail-oa0-f53.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752723Ab3H1Ni2 (ORCPT ); Wed, 28 Aug 2013 09:38:28 -0400 MIME-Version: 1.0 In-Reply-To: <20130828132703.GD3825@infradead.org> References: <20130826131121.GA26224@quad> <521BD4F8.5050504@gmail.com> <20130828132703.GD3825@infradead.org> Date: Wed, 28 Aug 2013 15:38:28 +0200 Message-ID: Subject: Re: [PATCH] perf mem: add priv level filtering support From: Stephane Eranian To: Arnaldo Carvalho de Melo Cc: David Ahern , LKML , Peter Zijlstra , "mingo@elte.hu" , Sukadev Bhattiprolu , Jiri Olsa , "ak@linux.intel.com" Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2119 Lines: 58 On Wed, Aug 28, 2013 at 3:27 PM, Arnaldo Carvalho de Melo wrote: > Em Mon, Aug 26, 2013 at 04:21:44PM -0600, David Ahern escreveu: >> On 8/26/13 7:11 AM, Stephane Eranian wrote: > >> >This patch adds the -u -and -k options to perf to allow >> >filtering of load/store sampling based on priv levels. >> >This may not be supported by all HW platforms. > > >> >+++ b/tools/perf/Documentation/perf-mem.txt >> >+-k:: >> >+ Only sample loads/stores at the user level (default: user + kernel) >> >+-u:: >> >+ Only sample loads/stores at the kernel level (default: user + kernel) > >> Are the descriptions backwards? In the commit message yuo have -u >> means user level and -k means kernel level; the help message here >> seems backwards. > > Looks like it is reversed, yes. > >> >+ OPT_BOOLEAN('u', "user-level", &mem.user, "include user-level accesses"), >> >+ OPT_BOOLEAN('k', "kernel-level", &mem.kernel, "include kernel-level accesses"), > > And its not clear to say that using -u will _exclude_ kernel samples, > just that it includes user samples, perf top has: > > -K, --hide_kernel_symbols hide kernel symbols > -U, --hide_user_symbols hide user symbols > > So perhaps we should change both to (and add this to 'report' as well): > > -U, --hide_kernel_symbols hide kernel symbols > -K, --hide_user_symbols hide user symbols > Well, I don't know what perf top does here but I don't want to hide the samples. I simply don't want to collect them (do not appear in the perf.data file). If that's what is happening in perf top, then I'll be glad to use the same options. > To state that: > > perf top -K > and > perf top --hide_user_symbols > > Are equivalent and asks for 'kernel only' samples, like it seems its the > intent (filtering) of Stephane here, and seems to clarify things? > > - Arnaldo -- 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/