From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754692Ab2AaPev (ORCPT ); Tue, 31 Jan 2012 10:34:51 -0500 Received: from rcsinet15.oracle.com ([148.87.113.117]:21285 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752193Ab2AaPer (ORCPT ); Tue, 31 Jan 2012 10:34:47 -0500 From: Konrad Rzeszutek Wilk To: linux-kernel@vger.kernel.org, lenb@kernel.org, len.brown@intel.com, linux-acpi@vger.kernel.org Cc: xen-devel@lists.xensource.com Subject: [RFC] Using per_cpu(processor) information to pipe it up the hypervisor. v1 Date: Tue, 31 Jan 2012 10:32:03 -0500 Message-Id: <1328023924-6858-1-git-send-email-konrad.wilk@oracle.com> X-Mailer: git-send-email 1.7.7.5 X-Source-IP: acsinet22.oracle.com [141.146.126.238] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090209.4F280A13.0025,ss=1,re=0.000,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I was wondering if you could advise me ontwo questions: - How to "get" ACPI PM information for processors that are down (either b/c of maxcpus=X or they are hot-plugged). The per_cpu(processor) is a great location to get all of this - but sadly it is not filled with information for dead CPUs. Is there another way to get this data? - Where should such a driver (see the patch please) live? I was thinking drivers/acpi/ but since the "processor" is an exported symbol it could live in drivers/xen as well? What is your feeling about it? Short description of the patch: It simple parses the "per_cpu(processor)" data and pipes it up the hypervisor and then unloads itself. It is a much shorter version of https://lkml.org/lkml/2011/11/30/245, but it does have the caveat that it does not work with 'maxcpus' or with hot-plugged CPUs or with limiting the amount of CPUs a guest can see. P.S. Also the name of it stinks. 'Sink' or 'plumber' initially came to my mind. Any thoughts of a better name? Thanks! drivers/xen/Kconfig | 5 + drivers/xen/Makefile | 2 +- drivers/xen/acpi_xen_sink.c | 265 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 271 insertions(+), 1 deletions(-)