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=-5.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY, USER_AGENT_SANE_1 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 0F3A9C433E0 for ; Tue, 14 Jul 2020 19:04:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E0B7222AAF for ; Tue, 14 Jul 2020 19:04:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=oracle.com header.i=@oracle.com header.b="0gYbMbZr" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731063AbgGNTEZ (ORCPT ); Tue, 14 Jul 2020 15:04:25 -0400 Received: from userp2130.oracle.com ([156.151.31.86]:53036 "EHLO userp2130.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730936AbgGNS4C (ORCPT ); Tue, 14 Jul 2020 14:56:02 -0400 Received: from pps.filterd (userp2130.oracle.com [127.0.0.1]) by userp2130.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 06EIg5nH123000; Tue, 14 Jul 2020 18:55:47 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=subject : to : cc : references : from : message-id : date : mime-version : in-reply-to : content-type : content-transfer-encoding; s=corp-2020-01-29; bh=zBSFWFJmK6H6QUNUzT1isFDg2o5kHAYgey+PVkvmy3A=; b=0gYbMbZrTAKzqSs2uR5NW6kMPhqX/DyK3rUF6liKEMQa3koTon0ow0cqknhFyywpq/wA Rbf/qWKjaJ6oUkh3kA1XsauNCBe+9dwPXZE3JFMZBXQxAkYtBmrQGc1m0FP+gxMUyLn0 mgTDeZfuIu9cyZ72cuAFJVAbMqgNJhwuLKrHAtiO7qOofQIb6rbeujmg2k/vcVEwYZNw bLg1guO8SSaA9zbBn9BMaq+I6V8CHulxgINt7q0/q13i8CLZyasB/SxLvYfz7bCgp8ia WagyEEEtcsMNbdU3R+4qLGlmEC4+4sPX8nuFkIaIA8kgmcIZ7u2DG3JyG65JAC1Eb3s1 1w== Received: from aserp3030.oracle.com (aserp3030.oracle.com [141.146.126.71]) by userp2130.oracle.com with ESMTP id 3274ur7afj-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL); Tue, 14 Jul 2020 18:55:46 +0000 Received: from pps.filterd (aserp3030.oracle.com [127.0.0.1]) by aserp3030.oracle.com (8.16.0.42/8.16.0.42) with SMTP id 06EIhbb1092521; Tue, 14 Jul 2020 18:55:45 GMT Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserp3030.oracle.com with ESMTP id 327q0ps5x5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Tue, 14 Jul 2020 18:55:45 +0000 Received: from abhmp0010.oracle.com (abhmp0010.oracle.com [141.146.116.16]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id 06EIthgF006460; Tue, 14 Jul 2020 18:55:43 GMT Received: from OracleT490.vogsphere (/73.203.30.179) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Tue, 14 Jul 2020 11:55:42 -0700 Subject: Re: [PATCH 0/2] iowait and idle fixes in /proc/stat To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, tglx@linutronix.de Cc: fweisbec@gmail.com, mingo@kernel.org, adobriyan@gmail.com References: <20200610210549.61193-1-tom.hromatka@oracle.com> From: Tom Hromatka Message-ID: <85937052-fcdf-8bd7-83ec-831a51e320cb@oracle.com> Date: Tue, 14 Jul 2020 12:55:41 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: <20200610210549.61193-1-tom.hromatka@oracle.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9682 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 mlxscore=0 malwarescore=0 spamscore=0 mlxlogscore=999 bulkscore=0 adultscore=0 phishscore=0 suspectscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007140133 X-Proofpoint-Virus-Version: vendor=nai engine=6000 definitions=9682 signatures=668680 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 lowpriorityscore=0 impostorscore=0 suspectscore=0 phishscore=0 spamscore=0 mlxlogscore=999 malwarescore=0 mlxscore=0 priorityscore=1501 adultscore=0 bulkscore=0 clxscore=1011 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2006250000 definitions=main-2007140133 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Ping. Thanks. Tom On 6/10/20 3:05 PM, Tom Hromatka wrote: > A customer is using /proc/stat to track cpu usage in a VM and noted > that the iowait and idle times behave strangely when a cpu goes > offline and comes back online. > > This patchset addresses two issues that can cause iowait and idle > to fluctuate up and down. With these changes, cpu iowait and idle > now only monotonically increase. > > Tom Hromatka (2): > tick-sched: Do not clear the iowait and idle times > /proc/stat: Simplify iowait and idle calculations when cpu is offline > > fs/proc/stat.c | 24 ++++++------------------ > kernel/time/tick-sched.c | 9 +++++++++ > 2 files changed, 15 insertions(+), 18 deletions(-) >