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 2EE70C43464 for ; Thu, 17 Sep 2020 22:16:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ED7962087D for ; Thu, 17 Sep 2020 22:16:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726187AbgIQWQX (ORCPT ); Thu, 17 Sep 2020 18:16:23 -0400 Received: from mga09.intel.com ([134.134.136.24]:38025 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725858AbgIQWQX (ORCPT ); Thu, 17 Sep 2020 18:16:23 -0400 IronPort-SDR: dNWQi4XcCpJ2FZpgB8vSbRA/w+dtGS4bc9/RX1aBd+o6OIQQvTxUa4ONTTZKFTkPU00TOHpjdq cOWmv2CIPgQA== X-IronPort-AV: E=McAfee;i="6000,8403,9747"; a="160732478" X-IronPort-AV: E=Sophos;i="5.77,272,1596524400"; d="scan'208";a="160732478" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Sep 2020 15:16:19 -0700 IronPort-SDR: N0HWBMh4w03AlXQmXuk6+BkORQkrqbWfTomEICfUR0WZFaOd7ue3XpWS2huC6CpqWBHKRzj8zE L8CwKYa8LCkg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.77,272,1596524400"; d="scan'208";a="303107760" Received: from linux.intel.com ([10.54.29.200]) by orsmga003.jf.intel.com with ESMTP; 17 Sep 2020 15:16:19 -0700 Received: from [10.251.12.27] (kliang2-MOBL.ccr.corp.intel.com [10.251.12.27]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by linux.intel.com (Postfix) with ESMTPS id A6AF45807C9; Thu, 17 Sep 2020 15:16:17 -0700 (PDT) Subject: Re: [PATCH V7 1/4] perf/core: Add PERF_SAMPLE_DATA_PAGE_SIZE To: Dave Hansen , peterz@infradead.org, mingo@redhat.com, acme@kernel.org, linux-kernel@vger.kernel.org Cc: mark.rutland@arm.com, alexander.shishkin@linux.intel.com, jolsa@redhat.com, eranian@google.com, ak@linux.intel.com, kirill.shutemov@linux.intel.com, mpe@ellerman.id.au, benh@kernel.crashing.org, paulus@samba.org References: <20200917135237.2857-1-kan.liang@linux.intel.com> <20200917135237.2857-2-kan.liang@linux.intel.com> <13427458-3934-1490-68bb-071be2ae01da@intel.com> <40234c70-720e-9c0d-1fc2-ac23c0acf721@linux.intel.com> <04f59f3b-2e53-8774-8333-63dfc5b8e6a9@intel.com> <0e2cd6e4-8016-ccf6-eaff-2b304cf966ee@linux.intel.com> <39dd016a-b0ee-c9da-dc21-1b7175e8b5ef@intel.com> From: "Liang, Kan" Message-ID: <88177517-da0c-43d9-4f5c-fb610e66b9e0@linux.intel.com> Date: Thu, 17 Sep 2020 18:16:15 -0400 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <39dd016a-b0ee-c9da-dc21-1b7175e8b5ef@intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 9/17/2020 6:02 PM, Dave Hansen wrote: >> The problem is that the warning from the perf tool usually includes some >> hints regarding the cause of the warning or possible solution to >> workaround/fix the warning. What message should we deliver to the users? >> "Warning: Too many error page size. Address space isolation feature may >> be enabled, please check"? > That's not particularly actionable for an end user. Do any of the perf > errors just tell them to submit a bug report? "Excessive number of page > size lookup errors, please report to..." Yes, found some perf tool warnings end with "Consider reporting to linux-kernel@vger.kernel.org." I will add a warning "Excessive number of page size lookup errors, please report to linux-kernel@vger.kernel.org.", if 90% of the samples have the page size 0. Thanks, Kan