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 648C6C4708C for ; Thu, 27 May 2021 19:01:36 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id F02DC6135C for ; Thu, 27 May 2021 19:01:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F02DC6135C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 2487E6B006C; Thu, 27 May 2021 15:01:35 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 1F8396B006E; Thu, 27 May 2021 15:01:35 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0728F6B0070; Thu, 27 May 2021 15:01:35 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0085.hostedemail.com [216.40.44.85]) by kanga.kvack.org (Postfix) with ESMTP id C9E2B6B006C for ; Thu, 27 May 2021 15:01:34 -0400 (EDT) Received: from smtpin28.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 60CD61814063B for ; Thu, 27 May 2021 19:01:34 +0000 (UTC) X-FDA: 78187929708.28.E6FB5C8 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by imf13.hostedemail.com (Postfix) with ESMTP id 38ABCE005F36 for ; Thu, 27 May 2021 19:01:24 +0000 (UTC) IronPort-SDR: EDVh+AxFfVxuIX0cYX/Wyx9ioWjqhnSB00BXWkSlRGzWnjqwwDBYmeMrd/JNhxdK7aQmlD3f1Y TdQoLOq3vP0g== X-IronPort-AV: E=McAfee;i="6200,9189,9997"; a="183147298" X-IronPort-AV: E=Sophos;i="5.83,228,1616482800"; d="scan'208";a="183147298" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga107.fm.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 Authentication-Results: imf13.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf13.hostedemail.com: domain of ak@linux.intel.com has no SPF policy when checking 192.55.52.151) smtp.mailfrom=ak@linux.intel.com X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 38ABCE005F36 X-Stat-Signature: 4uqmr88h9az6bgxy7xmu6g474nfndqdz X-HE-Tag: 1622142084-295129 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: > > 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.