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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 75520C433EF for ; Mon, 25 Apr 2022 23:19:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:In-Reply-To:From: References:To:Subject:Date:Message-ID:Reply-To:Cc:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=DCYziK+diieus7Zds73W9bql/iSe+HU2Y6T7FfcXu08=; b=TH3sREwpb4lAUNa3CGxvbUmMAo xutOhV7wLHGXxpLbnhRIf+/c4eRT1IBu7BELu1Lih40uXCswussxUfsajpAbdFJhqk79Agc2RNwTP WRbptdEuOeWxFAzMqCD9XXl8hwyveJIyXAXioDRpg0ARdcAdtK1oH074UCRSjYFAANVHUEAhFyj/I ybWxqg96FseQuMZKiKJ9nuMaopOKi+tb8TzJcXVt/ydUCx4gTB7Q5mZsJfDyWD4c+KPljbTJKy/Hi C+S6lOd1LgsAOB4nQW50XFx2QhgoG3OZeDdsZ+SESGa54ufJIp1cyvdCtmfItf8494zOSMHNnnO9Q 5uSS84Rg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nj7xy-00BiWM-41; Mon, 25 Apr 2022 23:18:02 +0000 Received: from mga03.intel.com ([134.134.136.65]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nj7xu-00BiV7-Qt for linux-arm-kernel@lists.infradead.org; Mon, 25 Apr 2022 23:18:00 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1650928678; x=1682464678; h=message-id:date:subject:to:references:from:in-reply-to: content-transfer-encoding:mime-version; bh=NsfmpBpnjXWdlYc2Hs+/yraJK+RP/S48CnqDHmpCjAI=; b=azirXMHkQx1NJ/F8XMsXvCSLQfHieoC0jXSNEvR94/Av7NSNTig2/dNv JdZmDYHheY7kIuSQ8RAHHqqF6iIrm98m5Lthc0dTBarBZYIqndhyhQGJe PJoaDMYpJArDK1c7ayTqVBXIHQAwVUWkbtWRX5Fmv3CSqoOHg/CJ0W9Nj b27UohU/kwVuDbCVQ5lxJ2/9nxj4wmZcxK4/NJznl7yUY7DFxxg0G2cwn m4dZeefhqmeYois0cxu/hgkppVXjZ5G8JMRweZKKqUqOYatlxVTRcbm3O 2AOc2qJDPLte4GtTN/O5VvWJ6pfd8cLgan+cztHjLb9pKZz605opahDJi Q==; X-IronPort-AV: E=McAfee;i="6400,9594,10328"; a="265193857" X-IronPort-AV: E=Sophos;i="5.90,289,1643702400"; d="scan'208";a="265193857" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Apr 2022 16:17:53 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.90,289,1643702400"; d="scan'208";a="729961184" Received: from orsmsx602.amr.corp.intel.com ([10.22.229.15]) by orsmga005.jf.intel.com with ESMTP; 25 Apr 2022 16:17:53 -0700 Received: from orsmsx607.amr.corp.intel.com (10.22.229.20) by ORSMSX602.amr.corp.intel.com (10.22.229.15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.27; Mon, 25 Apr 2022 16:17:53 -0700 Received: from orsmsx601.amr.corp.intel.com (10.22.229.14) by ORSMSX607.amr.corp.intel.com (10.22.229.20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.27; Mon, 25 Apr 2022 16:17:52 -0700 Received: from ORSEDG602.ED.cps.intel.com (10.7.248.7) by orsmsx601.amr.corp.intel.com (10.22.229.14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.27 via Frontend Transport; Mon, 25 Apr 2022 16:17:52 -0700 Received: from NAM12-MW2-obe.outbound.protection.outlook.com (104.47.66.43) by edgegateway.intel.com (134.134.137.103) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2308.27; Mon, 25 Apr 2022 16:17:52 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=jKe9U/n9w7NMj0ovzh+rr46H9c7m9VdQV1iuDJ3YSSCFKq9gUdr1+UBLDaF/tDDA0mMRFTo9LmrZEtjhkyYwCGWHw3giSsmBOopiChcAMNv4PhQ5xl/IPkeWResrlOgk/G2i9MFMsoNxmimmojmN7yIYuNGPJ9w+i4cjePWg9dUmg6IStQFJ7SXlALF5PizHFnfo2t3I3iJEx6E64nDLJ7x+uk7ILSBdNL272oygqGoz/98uA/b3NMvXXhfEGIKYOpHcYRCbfBfj0xIrXyL9W/FIhSs6mEKxotxBwLD5Atw3H9D6nCRDu3Rz2txHVZfSz+2xqGJTKYPzMtB+JtbfZA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=6DbLF3aFDikfQe0NAqE4PSReBd7Y15LHwjK+H4pIDJ8=; b=lY7jzGYvzX+hFOhrgsMDJl090d1SNr1rIhGz70lQoLWYhZfC1gw8vBKOhJcPWlFtC/ULUcjUsuQa7zkwEXCbAcScqizxuXTxUEUf6xiRLbFRPe7jRuTkEiLkkRQw3NpomfbhlOatmaffLSbcHGGKd9vZK4QR6IsFlkQE/vfJBqz6+gx1e8d3lz0ZeN1rf7ebRvFLltYM8aXsF7Ks7qEynnQrsIOaGO5IsfSTNsOQhoVYi1vg5dPaE/1LYG93qKUmPvQQyFdvVnBvMAFbgDj2G16iqrx9QrXz1POAhM+91M3lIymgKgdMCYvdAkRGboO1PVMsbmqaPz6UdXnHIGrnBA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=intel.com; Received: from BN0PR11MB5744.namprd11.prod.outlook.com (2603:10b6:408:166::16) by BYAPR11MB2565.namprd11.prod.outlook.com (2603:10b6:a02:c9::32) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5186.14; Mon, 25 Apr 2022 23:17:50 +0000 Received: from BN0PR11MB5744.namprd11.prod.outlook.com ([fe80::5459:7151:e684:6525]) by BN0PR11MB5744.namprd11.prod.outlook.com ([fe80::5459:7151:e684:6525%2]) with mapi id 15.20.5186.021; Mon, 25 Apr 2022 23:17:50 +0000 Message-ID: Date: Mon, 25 Apr 2022 16:17:46 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Firefox/91.0 Thunderbird/91.8.0 Subject: Re: [PATCH v3 6/9] x86: resctrl: pseudo_lock: Fix to restore to original value when re-enabling hardware prefetch register Content-Language: en-US To: Kohei Tarumizu , , , , , , , , , , , References: <20220420030223.689259-1-tarumizu.kohei@fujitsu.com> <20220420030223.689259-7-tarumizu.kohei@fujitsu.com> From: Reinette Chatre In-Reply-To: <20220420030223.689259-7-tarumizu.kohei@fujitsu.com> X-ClientProxiedBy: SJ0PR03CA0288.namprd03.prod.outlook.com (2603:10b6:a03:39e::23) To BN0PR11MB5744.namprd11.prod.outlook.com (2603:10b6:408:166::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 7fa38883-b90a-48c1-7637-08da2711d118 X-MS-TrafficTypeDiagnostic: BYAPR11MB2565:EE_ X-LD-Processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr X-Microsoft-Antispam-PRVS: X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:BN0PR11MB5744.namprd11.prod.outlook.com; PTR:; CAT:NONE; SFS:(13230001)(366004)(6636002)(186003)(2616005)(66556008)(66476007)(5660300002)(6666004)(6506007)(36756003)(6512007)(53546011)(26005)(31686004)(316002)(83380400001)(8676002)(66946007)(921005)(44832011)(8936002)(7416002)(508600001)(2906002)(38100700002)(966005)(31696002)(86362001)(82960400001)(6486002)(43740500002)(45980500001); DIR:OUT; SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?ZlZQWlp6WVhpWHhUcDlEV010T0Zob3JSRVVKL2ttTW9xcHZkYytvSG82bE13?= =?utf-8?B?aitXY2c2eC9FVGc0R3R5bFlhNDV2QTdRdzg4aVN0V2RKZGhhUndwQXFCc3dN?= =?utf-8?B?WG52SmxIMnpDUWI4TkpRNFpEMnhGb2kyQWgyenl0Qnh6S2lmYVVqWExnSDFw?= =?utf-8?B?d24zYkw0SVZobHJnUjdrcEgxbHF6S29qbm1NNk9YdllQQ0RsMXEycTVUd1U2?= =?utf-8?B?OHI2bmw4T3E5amFxQ2l6NVEwMjdqbnBpY0NDNldBdVRkdkp4eExqYkNsVk0z?= =?utf-8?B?T3ZnWERVTHdycDA0L1NWNFlyNUw4czlZbU1teUhpc29SOVZhVW5WUXZYR1l2?= =?utf-8?B?bUYvMkxLM282eHRmMm9PYnpmbFpsY3k5bjFrZmxEU1U4V0FHT0hNSmZkLzVr?= =?utf-8?B?VTRaM2E4MGxPZ3MvRW9UYyt4aTJXSnpCQmpFQ3pPaC93b0JMNkUwVW5PN1cv?= =?utf-8?B?WTZUakNtdUJBZEE1QWxBZWM4SWhIVUpjMk82VXBRb1lDZlplc3hrOTFyajNm?= =?utf-8?B?TnJwTGRIYk95UnpYemp3ejlMZStNRDlwR0JEL2dCSDRZODd5RXR3cVlOQUdP?= =?utf-8?B?RmtqUG1oWFVVc3RSWHFuZW9NWFZWOEtxcVE2dGV6QUtqSUxuVXZrcGh0NFJ4?= =?utf-8?B?b2dycDI0Zk9RSDVSaTB4UWNDR3ovUmljZzA3NUZIditxL3VoaGhTeXM2OVh1?= =?utf-8?B?azllSHNjQUQyZFMrRGM1UUR3VXlseTdwN2V5Nk1GbU1RMUxTSEdxQ0c1TDQ1?= =?utf-8?B?QzMxMUtuZU1lWmlYMXlsNlJkbXhNcGNiYjR3azc4ajAybEYzRWVjeFB0SHk5?= =?utf-8?B?djNmUGdkaDhXMGM4Si9Kb2U1RkRqcWN3OS9HcHdwSXAvN3lwMUxEWjNWUytZ?= =?utf-8?B?RmJsa0ZlV3F1MnFzYlRTTitKNWJLU2srRGFJR0VyL0phVXA5SXhlSFVLSEhl?= =?utf-8?B?Y1BqMjRUdzZqZFgwV2NDT2pOVzJoM3Z2eXd4Mk9RdmVZVmhaMkkxV1VjeWlE?= =?utf-8?B?VVpFdXNDRUwvdlZ0cmpXRFNFclNHdGRFNkRXYVAwK0J4OWErQ2NvbW42c3h2?= =?utf-8?B?anU1c2FENjRxNXJCckIxT2hvTjdSZXJXUDVnczRvVDFxOXpYL0NhWHFKMmhU?= =?utf-8?B?MHcrTEhnUW8xYlM4bUsxS1dyb0ZoSVM4alRqYWZrUUdYWlkxZTdZS1hzeUR5?= =?utf-8?B?WEY5UG5lLzZVU3JpQWlOblZVU3JBWVN0UldXR3g4MXVCT2xSSUd5Z3U0cTZM?= =?utf-8?B?b04ycXY1cUVoVEdyTGVNdk1ZWTgwOGJxeG1aT0V0amFHcWdvOWR2OVZ1WWVM?= =?utf-8?B?R0w1WGtXS2ZveWZxRmx3QkNNZ2YvOXU1VmVtK214MlFvcW8vZVpRcU5nRUR5?= =?utf-8?B?emdDNTB2NndpRGlwR0NIaG5VZW1RSzlPVlRvVTlieENuQ2tZZ0o0UzdPSkR5?= =?utf-8?B?YlppRjRvVm44YW9OU04zREw2a2N0a2M2RUoyVWpvVTN4QWVLbVRsNWVvUDZY?= =?utf-8?B?eUFEUytRYnBiNGZ1ZTlmWUZ3QU52ODlYTGplVi9WTldiQ1FReTlBRHMzVmpw?= =?utf-8?B?VVdpUmNGUVAzcTNwRlg2M09TQjJTYWF5OUJacTc1TmNKdDJyQTgrNmxjT0pr?= =?utf-8?B?ZTFrYzlndW5lcnY2MkZ0NndzTG50cGFtN2ZoSjg5OTRPMVI1RlJmZVg4VE1w?= =?utf-8?B?ZGprb1pUa0JBYkt1ZmVuQ3c1WFVoanFqU09TWmtKamVEMFhZV1ZUVlNXZXhD?= =?utf-8?B?dXdWTjFIbnRXbHY2K2VjMTBuekNaRnhFd3h2UTBxa2p1YW1HeHlFSWdJbGNq?= =?utf-8?B?L2JwTjNJQ2ZzaU5aeHNxeHpud3BVU2J4emllMDlyUlo2RlZYbnNwaGlOSEd5?= =?utf-8?B?MnJsTXlrcW52MWNPdUV5TnF5ck1BenhvbnVUcE9VY3Vqa1p2YTROSFc2emt1?= =?utf-8?B?c1ZPWGkwWWY0M2g2N2p0bXo4V0QvN29xSEErVmZxSDRQenBFSWFwWEhIa0VD?= =?utf-8?B?K2QvQXRHZEh6VVlsb1RvanFTZVZTUDdnSmpCTXpJaW5ZeHpBOE1rRXlRcjFv?= =?utf-8?B?dStXV1dsbThpTmVFekxDYUI0T2trVjVaSEVoU0s5TkRvN1RUc2QwWHhUVlpI?= =?utf-8?B?clF2NjhOUmM3TmxCRmthQmRZcy93cWNlY2pTMUIwblZzQjlEL0FUUkwwS25l?= =?utf-8?B?Y1JVbTJxdDMyZ2VLQ016ZEtsWDh6bnU0YVgwaHhRVDV4blFSRFMySkZuWHZP?= =?utf-8?B?aStFM2diQmdBQkEwcVFDelQ4VGlNN09jd3FvbWt3WTNPcnZlRnU2QTBudE5L?= =?utf-8?B?V1oxYUQwb3FjOVlZZnlaRllZK3F3WFRLQmpoVXdlL1BEMkZJUUs1NXZVNWky?= =?utf-8?Q?CL+HyVSorJ0SWmnM=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: 7fa38883-b90a-48c1-7637-08da2711d118 X-MS-Exchange-CrossTenant-AuthSource: BN0PR11MB5744.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Apr 2022 23:17:50.4970 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: nEjIIwXDd9eL/Oia5+8QB8GYRIDvEklWbFqH377ep3B4S1TOO+xgbHI+19NrUEqX+UBA953ELDK2B1S/Qd+4C4ECnt4CUgQrnrGwNDDqVCY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR11MB2565 X-OriginatorOrg: intel.com X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220425_161758_966717_917CA4CE X-CRM114-Status: GOOD ( 23.23 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Kohei, Thank you very much for catching this issue. This fix is not specific to or required by the driver you are creating in this series so you could also extract this patch and submit it separately as a fix to resctrl. When you do resubmit there are a few style related points that I highlight here, the fix itself looks good. For the subject, please use "x86/resctrl:" prefix in the subject. On 4/19/2022 8:02 PM, Kohei Tarumizu wrote: > The current pseudo_lock.c code overwrittes the value of the overwrittes -> overwrites > MSR_MISC_FEATURE_CONTROL to 0 even if the original value is not 0. > Therefore, modify it to save and restore the original values. > This needs a Fixes tag. A few patches are impacted by this fix: Fixes: 018961ae5579 ("x86/intel_rdt: Pseudo-lock region creation/removal core") Fixes: 443810fe6160 ("x86/intel_rdt: Create debugfs files for pseudo-locking testing") Fixes: 8a2fc0e1bc0c ("x86/intel_rdt: More precise L2 hit/miss measurements") > Signed-off-by: Kohei Tarumizu > --- > arch/x86/kernel/cpu/resctrl/pseudo_lock.c | 12 +++++++++--- > 1 file changed, 9 insertions(+), 3 deletions(-) > > diff --git a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c > index db813f819ad6..2d713c20f55f 100644 > --- a/arch/x86/kernel/cpu/resctrl/pseudo_lock.c > +++ b/arch/x86/kernel/cpu/resctrl/pseudo_lock.c > @@ -420,6 +420,7 @@ static int pseudo_lock_fn(void *_rdtgrp) > struct pseudo_lock_region *plr = rdtgrp->plr; > u32 rmid_p, closid_p; > unsigned long i; > + u64 saved_msr; > #ifdef CONFIG_KASAN > /* > * The registers used for local register variables are also used > @@ -463,6 +464,7 @@ static int pseudo_lock_fn(void *_rdtgrp) > * the buffer and evict pseudo-locked memory read earlier from the > * cache. > */ > + saved_msr = __rdmsr(MSR_MISC_FEATURE_CONTROL); > __wrmsr(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits, 0x0); > closid_p = this_cpu_read(pqr_state.cur_closid); > rmid_p = this_cpu_read(pqr_state.cur_rmid); > @@ -514,7 +516,7 @@ static int pseudo_lock_fn(void *_rdtgrp) > __wrmsr(IA32_PQR_ASSOC, rmid_p, closid_p); > > /* Re-enable the hardware prefetcher(s) */ > - wrmsr(MSR_MISC_FEATURE_CONTROL, 0x0, 0x0); > + wrmsrl(MSR_MISC_FEATURE_CONTROL, saved_msr); > local_irq_enable(); > > plr->thread_done = 1; > @@ -873,12 +875,14 @@ static int measure_cycles_lat_fn(void *_plr) > struct pseudo_lock_region *plr = _plr; > unsigned long i; > u64 start, end; > + u32 saved_low, saved_high; > void *mem_r; Please do follow the current style of using "reverse fir tree order". More information in: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/maintainer-tip.rst#n587 > > local_irq_disable(); > /* > * Disable hardware prefetchers. > */ > + rdmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high); > wrmsr(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits, 0x0); > mem_r = READ_ONCE(plr->kmem); > /* > @@ -895,7 +899,7 @@ static int measure_cycles_lat_fn(void *_plr) > end = rdtsc_ordered(); > trace_pseudo_lock_mem_latency((u32)(end - start)); > } > - wrmsr(MSR_MISC_FEATURE_CONTROL, 0x0, 0x0); > + wrmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high); > local_irq_enable(); > plr->thread_done = 1; > wake_up_interruptible(&plr->lock_thread_wq); > @@ -945,6 +949,7 @@ static int measure_residency_fn(struct perf_event_attr *miss_attr, > unsigned long i; > void *mem_r; > u64 tmp; > + u32 saved_low, saved_high; Same as above. > > miss_event = perf_event_create_kernel_counter(miss_attr, plr->cpu, > NULL, NULL, NULL); > @@ -973,6 +978,7 @@ static int measure_residency_fn(struct perf_event_attr *miss_attr, > /* > * Disable hardware prefetchers. > */ > + rdmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high); > wrmsr(MSR_MISC_FEATURE_CONTROL, prefetch_disable_bits, 0x0); > > /* Initialize rest of local variables */ > @@ -1031,7 +1037,7 @@ static int measure_residency_fn(struct perf_event_attr *miss_attr, > */ > rmb(); > /* Re-enable hardware prefetchers */ > - wrmsr(MSR_MISC_FEATURE_CONTROL, 0x0, 0x0); > + wrmsr(MSR_MISC_FEATURE_CONTROL, saved_low, saved_high); > local_irq_enable(); > out_hit: > perf_event_release_kernel(hit_event); Thank you very much. Reinette _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel