From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E970FC35249 for ; Wed, 5 Feb 2020 08:07:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BC2D92082E for ; Wed, 5 Feb 2020 08:07:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728020AbgBEIHy convert rfc822-to-8bit (ORCPT ); Wed, 5 Feb 2020 03:07:54 -0500 Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:54196 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725875AbgBEIHx (ORCPT ); Wed, 5 Feb 2020 03:07:53 -0500 Received: from pps.filterd (m0098414.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 01587jWZ138276 for ; Wed, 5 Feb 2020 03:07:52 -0500 Received: from e06smtp04.uk.ibm.com (e06smtp04.uk.ibm.com [195.75.94.100]) by mx0b-001b2d01.pphosted.com with ESMTP id 2xyhmgc2eu-1 (version=TLSv1.2 cipher=AES256-GCM-SHA384 bits=256 verify=NOT) for ; Wed, 05 Feb 2020 03:07:52 -0500 Received: from localhost by e06smtp04.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 5 Feb 2020 08:07:50 -0000 Received: from b06cxnps4074.portsmouth.uk.ibm.com (9.149.109.196) by e06smtp04.uk.ibm.com (192.168.101.134) with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted; (version=TLSv1/SSLv3 cipher=AES256-GCM-SHA384 bits=256/256) Wed, 5 Feb 2020 08:07:48 -0000 Received: from d06av23.portsmouth.uk.ibm.com (d06av23.portsmouth.uk.ibm.com [9.149.105.59]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 01587lc145875350 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 5 Feb 2020 08:07:47 GMT Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 0D01EA404D; Wed, 5 Feb 2020 08:07:47 +0000 (GMT) Received: from d06av23.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id AE019A4059; Wed, 5 Feb 2020 08:07:46 +0000 (GMT) Received: from localhost (unknown [9.124.35.138]) by d06av23.portsmouth.uk.ibm.com (Postfix) with ESMTP; Wed, 5 Feb 2020 08:07:46 +0000 (GMT) Date: Wed, 05 Feb 2020 13:37:45 +0530 From: "Naveen N. Rao" Subject: Re: [PATCH 2/3] powerpc/sysfs: Show idle_purr and idle_spurr for every CPU To: Christophe Leroy , "Gautham R. Shenoy" , Kamalesh Babulal , Michael Ellerman , Nathan Lynch , Vaidyanathan Srinivasan , Tyrel Datwyler Cc: linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org References: <1574856072-30972-1-git-send-email-ego@linux.vnet.ibm.com> <1574856072-30972-3-git-send-email-ego@linux.vnet.ibm.com> In-Reply-To: MIME-Version: 1.0 User-Agent: astroid/v0.15-13-gb675b421 (https://github.com/astroidmail/astroid) Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8BIT X-TM-AS-GCONF: 00 x-cbid: 20020508-0016-0000-0000-000002E3D0EB X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 20020508-0017-0000-0000-00003346AFF0 Message-Id: <1580889776.690kj4ppmj.naveen@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.138,18.0.572 definitions=2020-02-05_02:2020-02-04,2020-02-05 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 suspectscore=0 spamscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 lowpriorityscore=0 priorityscore=1501 phishscore=0 mlxscore=0 clxscore=1015 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2001150001 definitions=main-2002050065 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Christophe Leroy wrote: > > > Le 27/11/2019 à 13:01, Gautham R. Shenoy a écrit : >> From: "Gautham R. Shenoy" >> >> On Pseries LPARs, to calculate utilization, we need to know the >> [S]PURR ticks when the CPUs were busy or idle. >> >> The total PURR and SPURR ticks are already exposed via the per-cpu >> sysfs files /sys/devices/system/cpu/cpuX/purr and >> /sys/devices/system/cpu/cpuX/spurr. >> >> This patch adds support for exposing the idle PURR and SPURR ticks via >> /sys/devices/system/cpu/cpuX/idle_purr and >> /sys/devices/system/cpu/cpuX/idle_spurr. > > Might be a candid question, but I see in arch/powerpc/kernel/time.c that > PURR/SPURR are already taken into account by the kernel to calculate > utilisation when CONFIG_VIRT_CPU_ACCOUNTING_NATIVE is selected. > > As far as I understand, you are wanting to expose this to userland to > redo the calculation there. What is wrong with the values reported by > the kernel ? As you point out, it is only done with CONFIG_VIRT_CPU_ACCOUNTING_NATIVE, but isn't available with NO_HZ_FULL, which happens to be the distro default nowadays. - Naveen