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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 56D47C10F12 for ; Mon, 15 Apr 2019 17:59:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 244FE218A1 for ; Mon, 15 Apr 2019 17:59:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="XrlP/nXt" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727876AbfDOR7Q (ORCPT ); Mon, 15 Apr 2019 13:59:16 -0400 Received: from mail-qt1-f174.google.com ([209.85.160.174]:39271 "EHLO mail-qt1-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726740AbfDOR7O (ORCPT ); Mon, 15 Apr 2019 13:59:14 -0400 Received: by mail-qt1-f174.google.com with SMTP id t28so20202515qte.6; Mon, 15 Apr 2019 10:59:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:content-transfer-encoding:in-reply-to :user-agent; bh=iUbNRqXkA2hYDBip+liV2zR/eZgstbN0Rd5XbstZ9Bc=; b=XrlP/nXtgc0mpm+HAKIMzWshnbS4iDrSJT1QxioOyIeRINBX7k35/+iykP6uP2r1QZ E1dUBarzGdMElPhmt7DZRgcZ5UF2MO9st3nDj12XHt/9ZDudalkasLk6fHKuzMlpToI0 WtTG8NhgVd09K1OdMHaeqx6J1Ks9YBA4mKhYzHttY3lasUZZmhr9S4CWw2xZXYFG7o2m mqINdka8V2G4PdRPmbayr/Zxvb1xXTst/vnWLTHSdRlWqI9vWMQo3H3zlQLmgpN4NdOq 3pWGaoH4jZgy7w2wReIbFmyZxeaGHE7yCHIrrV5JxAmpJOkKb9YeZ6o0xRgXr15zCEdB BHsQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:content-transfer-encoding :in-reply-to:user-agent; bh=iUbNRqXkA2hYDBip+liV2zR/eZgstbN0Rd5XbstZ9Bc=; b=kQEAs7sLbW0ZQerbtMW59UvCIjdx8New2yTqDt8fbHfkGfJHJymTgUrze/jYr0kPZZ gHuD9ktjbVVHtPFUr/uxGSRDOwuaF+CIUCEXnzfmsWrqclPkEgZ7onvEv2r6wMQqDQ0w IESYAhjdK3YPCSJpAMq8Up0aQvqvbqrtl4P3Y3y+jG1ibzUH3o5rMwc3B1RsF7ZvHBMz ghtFW8khAGTfCPOkA9cC4U0A/1dbIsMLcyNakNn0FZheeUTytvlfn8YXbB4Q+O/C3Abs irwCEzEtOuHO6MGwS6iyZIUKh+GtD8sJrZL/c+vsx5Hf1Pvmi4Put2T+cqFoEVw+U9aR EKug== X-Gm-Message-State: APjAAAXSe2Fk+lfc8eXcZEYGgtlh9wJc0iHxcrwhb9sCRyx0esd5sJXn ZZY9OMBO9i+Oja20mqIRmU8= X-Google-Smtp-Source: APXvYqyBBubcfYyk/wegcfOGgqaWNWAyImssms8Z8PF8aPqKgKqwG82Sk2FmQx8HU597GKKDDRqxjQ== X-Received: by 2002:ac8:2f4a:: with SMTP id k10mr64641508qta.208.1555351152372; Mon, 15 Apr 2019 10:59:12 -0700 (PDT) Received: from quaco.ghostprotocols.net ([190.15.121.82]) by smtp.gmail.com with ESMTPSA id p27sm30894604qte.25.2019.04.15.10.59.10 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Mon, 15 Apr 2019 10:59:11 -0700 (PDT) From: Arnaldo Carvalho de Melo X-Google-Original-From: Arnaldo Carvalho de Melo Received: by quaco.ghostprotocols.net (Postfix, from userid 1000) id 9A0B54039C; Mon, 15 Apr 2019 14:59:07 -0300 (-03) Date: Mon, 15 Apr 2019 14:59:07 -0300 To: Paul Clarke Cc: Linhaifeng , "linux-perf-users@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: perf tools:Is there any tools to found out the max latency by irq or cpu idle Message-ID: <20190415175907.GC11294@kernel.org> References: <4099DE2E54AFAD489356C6C9161D53339591D64A@DGGEML502-MBX.china.huawei.com> <8ce8c596-123e-1342-5ccc-06a5fd8a60ec@redhat.com> <4099DE2E54AFAD489356C6C9161D53339591DE6D@DGGEML502-MBX.china.huawei.com> <6e6a98a4-a442-1e10-cf5a-56b6792d42ba@us.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <6e6a98a4-a442-1e10-cf5a-56b6792d42ba@us.ibm.com> X-Url: http://acmel.wordpress.com User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Em Mon, Apr 15, 2019 at 07:52:59AM -0500, Paul Clarke escreveu: > On 4/13/19 1:01 AM, Linhaifeng wrote: > > Sorry, the value 131081408 is just for example. Actually the result is like this: > > sqrt 2019-04-10 23:53:50: 43968 > > sqrt 2019-04-10 23:53:51: 44060 > > sqrt 2019-04-10 23:53:52: 49012 > > sqrt 2019-04-10 23:53:53: 38172 > > sqrt 2019-04-10 23:53:54: 131081408 > > sqrt 2019-04-10 23:53:55: 43600 > > sqrt 2019-04-10 23:53:56: 46704 > > sqrt 2019-04-10 23:53:57: 46880 > > sqrt 2019-04-10 23:53:58: 44332 > > …… > > sqrt 2019-04-10 02:17:15: 136345876 > > …… > > sqrt 2019-04-10 04:40:35: 136335644 > > …… > > Given the periodicity, I'm wondering if it could be System Management Interrupts (SMIs)? > > If so, some BIOSes have settings to mitigate, otherwise, there's not much that can be done, per my understanding. [root@quaco perf]# perf list smi List of pre-defined events (to be used in -e): msr/smi/ [Kernel PMU event] sunrpc:xprt_transmit [Tracepoint event] tcp:tcp_retransmit_skb [Tracepoint event] tcp:tcp_retransmit_synack [Tracepoint event] sdt_qemu:qmp_block_job_dismiss [SDT event] sdt_qemu:qmp_job_dismiss [SDT event] Metric Groups: [root@quaco perf]# Here, using it: [root@quaco perf]# perf stat -I 1000 -e msr/smi/ # time counts unit events 1.000919819 0 msr/smi/ 2.001689950 0 msr/smi/ 3.002266988 0 msr/smi/ 4.003049439 16 msr/smi/ 5.003676064 0 msr/smi/ 6.004420613 16 msr/smi/ ^C 6.609405666 0 msr/smi/ [root@quaco perf]# In this Lenovo T480s I generate SMIs by pressing the mute button :-) - Arnaldo