From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753023AbeCTLIP (ORCPT ); Tue, 20 Mar 2018 07:08:15 -0400 Received: from userp2120.oracle.com ([156.151.31.85]:47246 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752136AbeCTLIL (ORCPT ); Tue, 20 Mar 2018 07:08:11 -0400 Subject: Re: [PATCH v3] xen/acpi: upload _PSD info for non Dom0 CPUs too To: "Rafael J. Wysocki" Cc: Boris Ostrovsky , Linux Kernel Mailing List , Juergen Gross , "Rafael J. Wysocki" , Len Brown , Robert Moore , Erik Schmauss , xen-devel@lists.xenproject.org, ACPI Devel Maling List , devel@acpica.org References: <20180315142205.15839-1-joao.m.martins@oracle.com> From: Joao Martins Message-ID: <5549560b-44ba-8063-de11-2e74b99a3e20@oracle.com> Date: Tue, 20 Mar 2018 11:07:51 +0000 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8837 signatures=668693 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=1 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1711220000 definitions=main-1803200127 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/20/2018 09:41 AM, Rafael J. Wysocki wrote: > On Fri, Mar 16, 2018 at 2:57 PM, Joao Martins wrote: >> On 03/15/2018 03:45 PM, Boris Ostrovsky wrote: >>> On 03/15/2018 10:22 AM, Joao Martins wrote: >>>> All uploaded PM data from non-dom0 CPUs takes the info from vCPU 0 and >>>> changing only the acpi_id. For processors which P-state coordination type >>>> is HW_ALL (0xFD) it is OK to upload bogus P-state dependency information >>>> (_PSD), because Xen will ignore any cpufreq domains created for past CPUs. >>>> >>>> Albeit for platforms which expose coordination types as SW_ANY or SW_ALL, >>>> this will have some unintended side effects. Effectively, it will look at >>>> the P-state domain existence and *if it already exists* it will skip the >>>> acpi-cpufreq initialization and thus inherit the policy from the first CPU >>>> in the cpufreq domain. This will finally lead to the original cpu not >>>> changing target freq to P0 other than the first in the domain. Which will >>>> make turbo boost not getting enabled (e.g. for 'performance' governor) for >>>> all cpus. >>>> >>>> This patch fixes that, by also evaluating _PSD when we enumerate all ACPI >>>> processors and thus always uploading the correct info to Xen. We export >>>> acpi_processor_get_psd() for that this purpose, but change signature >>>> to not assume an existent of acpi_processor given that ACPI isn't creating >>>> an acpi_processor for non-dom0 CPUs. >>>> >>>> Signed-off-by: Joao Martins >>> >>> Reviewed-by: Boris Ostrovsky >>> >> Thanks! >> >> I suppose what's remaining is review (or ack) from ACPI folks on the interface >> changes made to acpi_processor_get_psd(). > > There you go: > > Acked-by: Rafael J. Wysocki > Thank you! > Do you want to route this via Xen? > I suppose that makes sense given that the majority of the change is on xen acpi processor. But it's ultimately Boris/Juergen call. Joao