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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,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 7334EC47089 for ; Thu, 27 May 2021 19:02:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5B098613DC for ; Thu, 27 May 2021 19:02:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236942AbhE0TEC (ORCPT ); Thu, 27 May 2021 15:04:02 -0400 Received: from mga18.intel.com ([134.134.136.126]:52731 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236934AbhE0TD1 (ORCPT ); Thu, 27 May 2021 15:03:27 -0400 IronPort-SDR: cVTjymvlmxZiFNZYIT6oaInAMzy3iohtx1p6wg2cfoVR8bcBLoxylOmsfEx2XWVX0cu8mBtlAo DvEvf3DnQbhg== X-IronPort-AV: E=McAfee;i="6200,9189,9997"; a="190183293" X-IronPort-AV: E=Sophos;i="5.83,228,1616482800"; d="scan'208";a="190183293" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 May 2021 12:01:24 -0700 IronPort-SDR: hIC7PXPO7MWKRMWUsJ4NNFkVDWx77kRMBHUjw5SdKspD43X+bDu5wBWg39NQQtWPtHJoAfykch UB+OX7CUvC6g== X-IronPort-AV: E=Sophos;i="5.83,228,1616482800"; d="scan'208";a="415021225" Received: from akleen-mobl1.amr.corp.intel.com (HELO [10.252.135.183]) ([10.252.135.183]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 May 2021 12:01:23 -0700 Subject: Re: [clocksource] 8901ecc231: stress-ng.lockbus.ops_per_sec -9.5% regression To: paulmck@kernel.org, Feng Tang Cc: kernel test robot , John Stultz , Thomas Gleixner , Stephen Boyd , Jonathan Corbet , Mark Rutland , Marc Zyngier , Xing Zhengjun , Chris Mason , LKML , Linux Memory Management List , lkp@lists.01.org, lkp@intel.com, ying.huang@intel.com, zhengjun.xing@intel.com References: <20210521083322.GG25531@xsang-OptiPlex-9020> <20210521135617.GT4441@paulmck-ThinkPad-P17-Gen-1> <20210522160827.GA2625834@paulmck-ThinkPad-P17-Gen-1> <20210526064922.GD5262@shbuild999.sh.intel.com> <20210526134911.GB4441@paulmck-ThinkPad-P17-Gen-1> <20210527182959.GA437082@paulmck-ThinkPad-P17-Gen-1> From: Andi Kleen Message-ID: <138f81df-08e1-f96e-1915-c58b44f96a41@linux.intel.com> Date: Thu, 27 May 2021 12:01:23 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.10.2 MIME-Version: 1.0 In-Reply-To: <20210527182959.GA437082@paulmck-ThinkPad-P17-Gen-1> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > Nevertheless, it is quite possible that real-world use will result in > some situation requiring that high-stress workloads run on hardware > not designed to accommodate them, and also requiring that the kernel > refrain from marking clocksources unstable. > > Therefore, provide an out-of-tree patch that reacts to this situation out-of-tree means it will not be submitted? I think it would make sense upstream, but perhaps guarded with some option.