From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752391Ab0KXIcG (ORCPT ); Wed, 24 Nov 2010 03:32:06 -0500 Received: from canuck.infradead.org ([134.117.69.58]:53291 "EHLO canuck.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751650Ab0KXIcF convert rfc822-to-8bit (ORCPT ); Wed, 24 Nov 2010 03:32:05 -0500 Subject: Re: [rfc 3/3] perf, x86: P4 PMU -- export ABI part of event config to userspace From: Peter Zijlstra To: Cyrill Gorcunov Cc: Ingo Molnar , LKML , ming.m.lin@intel.com, eranian@google.com In-Reply-To: <20101123224800.658686382@openvz.org> References: <20101123224601.766827604@openvz.org> <20101123224800.658686382@openvz.org> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Wed, 24 Nov 2010 09:32:17 +0100 Message-ID: <1290587537.2072.430.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2010-11-24 at 01:46 +0300, Cyrill Gorcunov wrote: > plain text document attachment (x86-perf-export-abi) > Due to tight 64 bit size of event config field (where we have to track > pretty lot of info during event lifetime) some bits are to be exported > via header into userspace. > > Signed-off-by: Cyrill Gorcunov > CC: Lin Ming > CC: Stephane Eranian > CC: Peter Zijlstra > --- > > Note that I don't like much the idea to export anything into userspace > but it seems there is no other choise. So there is a minimum which should > be exported. Could you say what exactly is exposed to userspace and why?