From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752637AbcHLWvE (ORCPT ); Fri, 12 Aug 2016 18:51:04 -0400 Received: from mail-cys01nam02on0121.outbound.protection.outlook.com ([104.47.37.121]:26544 "EHLO NAM02-CY1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752520AbcHLWvC (ORCPT ); Fri, 12 Aug 2016 18:51:02 -0400 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=waiman.long@hpe.com; Message-ID: <57AE52CE.3040302@hpe.com> Date: Fri, 12 Aug 2016 18:50:54 -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: Dave Hansen CC: Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , , , Borislav Petkov , Andy Lutomirski , Prarit Bhargava , Scott J Norton , Douglas Hatch , Randy Wright Subject: Re: [PATCH v5] x86/hpet: Reduce HPET counter read contention References: <1471037130-60583-1-git-send-email-Waiman.Long@hpe.com> <57AE41F3.6030107@intel.com> In-Reply-To: <57AE41F3.6030107@intel.com> Content-Type: text/plain; charset="windows-1252"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [72.71.243.96] X-ClientProxiedBy: BN6PR08CA0052.namprd08.prod.outlook.com (10.172.144.14) To DF4PR84MB0313.NAMPRD84.PROD.OUTLOOK.COM (10.162.193.27) X-MS-Office365-Filtering-Correlation-Id: 391f36c9-114a-4cfd-ac74-08d3c30320db X-Microsoft-Exchange-Diagnostics: 1;DF4PR84MB0313;2:goGe1ydVfjD9J2dTYENFF4g32hR7bpZxFuTQZC66/NXvdMDNv//0AR7ISsVgdd0rowqbTSs97I6iyxYTC/nH9Uesm7ByifYMUQPKzcxYATVh+K2g4sTOgN0Z6Ma8x8QiABidAK+33iN79PXQLxx8mgjjpBANwk+8RoYAujDCTVzrMY14ux6P49rr8eI9Qim5;3:rlE99Mi3Q8OEnWtx7rur09UbArbfZWguO5OCkcDFOolgLaxku/M75MBP0rM2lSwfs0kFfUzmWAumUo0SVSh3YVOWP9bAOnjj5CBQWJGWgBOo+dmms1ZgmbvAK+ChLhZ8 X-Microsoft-Antispam: UriScan:;BCL:0;PCL:0;RULEID:;SRVR:DF4PR84MB0313; 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It is explicitly assumed that the raw spinlock >> + * size is 32-bit. > So what happens when we have all the fun debugging options on? > >> typedef struct raw_spinlock { >> arch_spinlock_t raw_lock; >> #ifdef CONFIG_GENERIC_LOCKBREAK >> unsigned int break_lock; >> #endif >> #ifdef CONFIG_DEBUG_SPINLOCK >> unsigned int magic, owner_cpu; >> void *owner; >> #endif >> #ifdef CONFIG_DEBUG_LOCK_ALLOC >> struct lockdep_map dep_map; >> #endif >> } raw_spinlock_t; Sorry, it should be arch_spinlock_t instead. Will fix that. Cheers, Longman