From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756037Ab3CDEVQ (ORCPT ); Sun, 3 Mar 2013 23:21:16 -0500 Received: from ozlabs.org ([203.10.76.45]:43794 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755418Ab3CDEVN (ORCPT ); Sun, 3 Mar 2013 23:21:13 -0500 From: Michael Ellerman To: acme@infradead.org Cc: peterz@infradead.org, jolsa@redhat.com, , linux-doc@vger.kernel.org, rob@landley.net Subject: [RFC/PATCH] perf: Expand definition of sysfs format attribute Date: Mon, 4 Mar 2013 15:21:05 +1100 Message-Id: <1362370865-4437-1-git-send-email-michael@ellerman.id.au> X-Mailer: git-send-email 1.7.10.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Make it explicit that the format attributes may define overlapping bit ranges. Unfortunately this was left unspecified originally, and all the examples show non-overlapping ranges. I don't believe this is an ABI change, as we are defining something that was previously undefined, but others may disagree. The POWER8 PMU would like to define overlapping ranges, as bit ranges in the event code have different meanings for certain events. It will also allow us to define an overarching "event" field, that encompasses all others. As far as I can see perf is comfortable with this change, however I am not sure if there are any other users of the interface. Signed-off-by: Michael Ellerman --- Documentation/ABI/testing/sysfs-bus-event_source-devices-format | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-bus-event_source-devices-format b/Documentation/ABI/testing/sysfs-bus-event_source-devices-format index 079afc7..77f47ff 100644 --- a/Documentation/ABI/testing/sysfs-bus-event_source-devices-format +++ b/Documentation/ABI/testing/sysfs-bus-event_source-devices-format @@ -9,6 +9,12 @@ Description: we want to export, so that userspace can deal with sane name/value pairs. + Userspace must be prepared for the possibility that attributes + define overlapping bit ranges. For example: + attr1 = 'config:0-23' + attr2 = 'config:0-7' + attr3 = 'config:12-35' + Example: 'config1:1,6-10,44' Defines contents of attribute that occupies bits 1,6-10,44 of perf_event_attr::config1. -- 1.7.10.4