From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964856AbcIFR0W (ORCPT ); Tue, 6 Sep 2016 13:26:22 -0400 Received: from mail-by2nam03on0091.outbound.protection.outlook.com ([104.47.42.91]:26064 "EHLO NAM03-BY2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S936286AbcIFR0S (ORCPT ); Tue, 6 Sep 2016 13:26:18 -0400 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=waiman.long@hpe.com; Message-ID: <57CEF892.3090301@hpe.com> Date: Tue, 6 Sep 2016 13:10:42 -0400 From: Waiman Long User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:10.0.12) Gecko/20130109 Thunderbird/10.0.12 MIME-Version: 1.0 To: Thomas Gleixner CC: Ingo Molnar , "H. Peter Anvin" , , , Borislav Petkov , Andy Lutomirski , Dave Hansen , Prarit Bhargava , Scott J Norton , Douglas Hatch , Randy Wright Subject: Re: [RESEND PATCH v6] x86/hpet: Reduce HPET counter read contention References: <1473175676-27713-1-git-send-email-Waiman.Long@hpe.com> In-Reply-To: Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [72.71.243.83] X-ClientProxiedBy: SN1PR17CA0006.namprd17.prod.outlook.com (10.169.33.144) To TU4PR84MB0317.NAMPRD84.PROD.OUTLOOK.COM (10.162.186.27) X-MS-Office365-Filtering-Correlation-Id: cd3f0e13-0da3-4fe3-8577-08d3d678bf10 X-Microsoft-Exchange-Diagnostics: 1;TU4PR84MB0317;2:LTo+buWS8jxYvhxU/F7Ben9Cih3m3tagvhjBdL3Ohobh3Rsa34fMt/8EQZDn0nQqCC+446u+uDF2MvzLe393W2pS4Wj0vqpqFXLWDsYWN5zESOkndKBmrMdkO+EuL74L64JrRltGSwUWH2FF9nt87t8ZNXiusuLH4VkMKT0OjOsvFZ2UFER1rmTZXetFfaIl;3:u7hGBQbS5rgmJ2DKXN+0B1tzys7r5EXDjz/PRz74mRD1k0GAaBYS8aVLdHQ9xMJ48fZwNqXHYWTSkol901uvfbxZioWOb6RYJpsLDwVrtQ97KGM9meWkxecrxxELFwaV X-Microsoft-Antispam: UriScan:;BCL:0;PCL:0;RULEID:;SRVR:TU4PR84MB0317; 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The CPU that gets the bit lock will be responsible for >> reading the HPET counter and update the sequence number. The others >> will monitor the change in sequence number and grab the HPET counter >> value accordingly. This change is only enabled on SMP configuration. > That hardly matches the implementation. > > Thanks, > > tglx Sorry, I forgot to update the change log accordingly. Will send out a new patch to address that. Cheers, Longman