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=-4.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,URIBL_BLOCKED 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 45D1EC072B5 for ; Fri, 24 May 2019 19:25:38 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 19CA5217F9 for ; Fri, 24 May 2019 19:25:38 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="r4lP6yVj"; dkim=fail reason="signature verification failed" (2048-bit key) header.d=marvell.com header.i=@marvell.com header.b="LlWWv6uq"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=marvell.onmicrosoft.com header.i=@marvell.onmicrosoft.com header.b="X/AWA2rW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 19CA5217F9 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=marvell.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Content-ID:In-Reply-To: References:Message-ID:Date:Subject:To:From:Reply-To:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=5xeka3thVtgvglK3tTH97RGIqnu+DZH55JuE8tMv/bw=; b=r4lP6yVjIs64lH TWLqp7ztzps1uVODsIhfwNumfqaCQNZIAmem94GOrlM6JyY+vARqIT5/849enuKxhHBQz5iTgMR5y F/pSfknBohcYh+Bh22neJc7VU/mg/z/37jc0PM6BcT3mEXXnItvrlyimJvNuIc3cqBJfyKbckVFvl CZ/MpF7TZdKDscdNzahHxgeXrOz03eNy0ZM28aRnUEerqDUZxRjT+89J8j4nzQWX/Rx+S+Bcxdn4Q 0Oe8YU1rT8oL0ft1on0qWhDvRyNu8y0T9zg6KvanjLvWDpfU8kBIzYVx3dz9akt2cjX2wWgyaotoB AY62urXfBxE7CqnNoSGQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hUFom-0003GF-VA; Fri, 24 May 2019 19:25:29 +0000 Received: from mx0a-0016f401.pphosted.com ([67.231.148.174] helo=mx0b-0016f401.pphosted.com) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hUFoe-0003FR-Vs for linux-arm-kernel@lists.infradead.org; Fri, 24 May 2019 19:25:22 +0000 Received: from pps.filterd (m0045849.ppops.net [127.0.0.1]) by mx0a-0016f401.pphosted.com (8.16.0.27/8.16.0.27) with SMTP id x4OJP5Hl028312; Fri, 24 May 2019 12:25:05 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=marvell.com; h=from : to : cc : subject : date : message-id : references : in-reply-to : content-type : content-id : content-transfer-encoding : mime-version; s=pfpt0818; bh=+gNQTDIKHly1DzzY6EQH7ChEagtnUyGBGI93erMBQTE=; b=LlWWv6uqzeqI713GzO0pg0u/JsHLhLCmT2URCtXaJbCQxMpGPwWj+7lHUn0UxMLbfe9w gz10XznJGWME6mEZ9x6SiZIgG6MjN7ktVKRT3mjr2K8HG3CjnoAv5mZ3ZHPjBoQtRDyB U9f8C1iClDkfK4ClCyoD61tk1k8hoC0Y/8JDFaAD2ork5rRpC4UPqd8wL6ZJo2Wn7Dx8 cjsKT/ibWMWJztxiF+M8QbiFDKjhfTKZz1CVrtn3PzGXnTtbIrNRG8XovBYt/bDgA3AC GbuYUz6XCpgE5/Q0OYbOsSKxfeQUjKbIDCLu/ydz/n3YM2Pog/zNGET1kqvuBeZYigrp qQ== Received: from sc-exch03.marvell.com ([199.233.58.183]) by mx0a-0016f401.pphosted.com with ESMTP id 2spmjcrkrv-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-SHA384 bits=256 verify=NOT); Fri, 24 May 2019 12:25:00 -0700 Received: from SC-EXCH02.marvell.com (10.93.176.82) by SC-EXCH03.marvell.com (10.93.176.83) with Microsoft SMTP Server (TLS) id 15.0.1367.3; Fri, 24 May 2019 12:24:59 -0700 Received: from NAM05-BY2-obe.outbound.protection.outlook.com (104.47.50.51) by SC-EXCH02.marvell.com (10.93.176.82) with Microsoft SMTP Server (TLS) id 15.0.1367.3 via Frontend Transport; Fri, 24 May 2019 12:24:59 -0700 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=marvell.onmicrosoft.com; s=selector2-marvell-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=+gNQTDIKHly1DzzY6EQH7ChEagtnUyGBGI93erMBQTE=; b=X/AWA2rWOA79UT94L4RplImjjZCeRcEZOwe1sQ0HGhKJfdXTH7qgVJLO+ZgyCFb8VCOtTVKk2kOEzWslQ7H4M3I+l+/EX+SBDoMFQH7Kj9iAgzqa4tIszZaU6hSV+jlAfMpTNj2zR+VDTtYAjdlYJiabNuW8fvL+5n5jSTeb0m4= Received: from CY4PR1801MB1942.namprd18.prod.outlook.com (10.171.255.33) by CY4PR1801MB1880.namprd18.prod.outlook.com (10.171.255.19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1922.15; Fri, 24 May 2019 19:24:55 +0000 Received: from CY4PR1801MB1942.namprd18.prod.outlook.com ([fe80::f4b5:9677:2811:41f4]) by CY4PR1801MB1942.namprd18.prod.outlook.com ([fe80::f4b5:9677:2811:41f4%7]) with mapi id 15.20.1922.018; Fri, 24 May 2019 19:24:55 +0000 From: Jayachandran Chandrasekharan Nair To: Aaro Koskinen Subject: Re: [EXT] Re: [PATCH] arm64: Improve parking of stopped CPUs Thread-Topic: [EXT] Re: [PATCH] arm64: Improve parking of stopped CPUs Thread-Index: AQHVDcfCkz9GqQa430G2XsGiHVdW86ZxgtYAgAkuTgA= Date: Fri, 24 May 2019 19:24:55 +0000 Message-ID: <20190524192446.GA29866@dc5-eodlnx05.marvell.com> References: <1485942532-2643-1-git-send-email-jnair@caviumnetworks.com> <20190516184452.GE10985@darkstar.musicnaut.iki.fi> <20190518221929.GA6135@dc5-eodlnx05.marvell.com> <20190518231244.GC3713@t60.musicnaut.iki.fi> In-Reply-To: <20190518231244.GC3713@t60.musicnaut.iki.fi> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: BY5PR04CA0012.namprd04.prod.outlook.com (2603:10b6:a03:1d0::22) To CY4PR1801MB1942.namprd18.prod.outlook.com (2603:10b6:910:7a::33) x-ms-exchange-messagesentrepresentingtype: 1 x-originating-ip: [199.233.59.128] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 8472dd07-da42-493a-343f-08d6e07d8083 x-microsoft-antispam: BCL:0; PCL:0; RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600141)(711020)(4605104)(2017052603328)(7193020); SRVR:CY4PR1801MB1880; x-ms-traffictypediagnostic: CY4PR1801MB1880: x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:7691; x-forefront-prvs: 0047BC5ADE x-forefront-antispam-report: SFV:NSPM; SFS:(10009020)(376002)(346002)(39850400004)(136003)(366004)(396003)(54094003)(43544003)(199004)(189003)(229853002)(476003)(33656002)(6486002)(6436002)(486006)(66066001)(6512007)(316002)(11346002)(446003)(71190400001)(71200400001)(73956011)(66946007)(66476007)(66556008)(64756008)(66446008)(256004)(14444005)(305945005)(99286004)(6916009)(54906003)(102836004)(76176011)(7736002)(52116002)(6506007)(8676002)(81156014)(81166006)(8936002)(386003)(68736007)(6116002)(3846002)(6246003)(4326008)(186003)(53936002)(26005)(25786009)(14454004)(478600001)(86362001)(2906002)(5660300002)(1076003); DIR:OUT; SFP:1101; SCL:1; SRVR:CY4PR1801MB1880; H:CY4PR1801MB1942.namprd18.prod.outlook.com; FPR:; SPF:None; LANG:en; PTR:InfoNoRecords; A:1; MX:1; received-spf: None (protection.outlook.com: marvell.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: QzdzOVN/fn5zEi3jB9jerhYDS+JwVcfheS+1Fs48uMpSY9I50R3egvyPCJUrDCo86Y3fmJfhtmGOywzemyCs470WY0Xm1JMwIk76Q9IBRQc6iTfIg3vpttKIKdUJh0DmjqNlPUdf+vFnh0t3/u3wHxPo+ArvVId3FN4sOLE/CzUa9jbfLzwR0kM2Y3z8Dtg8FSEmPGLbiTeQIsHO7UnSz5Kfom5Gl0Vq265Cw9yIGQsZWY8GLNVcRw+JgY4IGPWNZTEpd2baa+4aQ/Za+oY0gFMw/uvlvy6+O/3g8VuK9eAhGy4hMXNuUTe2TSnOqByh/Uf9xWsy33a0pI8WvN5+jH9a3zqpdY2cXkIAcycqHwQHP1cr9RYtHW31VUz/fpuGpdX6V/Z8gzT6xarJugfhis2dqIYqrVVdVT9Wv4yGCk8= Content-ID: MIME-Version: 1.0 X-MS-Exchange-CrossTenant-Network-Message-Id: 8472dd07-da42-493a-343f-08d6e07d8083 X-MS-Exchange-CrossTenant-originalarrivaltime: 24 May 2019 19:24:55.4038 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 70e1fb47-1155-421d-87fc-2e58f638b6e0 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: jnair@marvell.com X-MS-Exchange-Transport-CrossTenantHeadersStamped: CY4PR1801MB1880 X-OriginatorOrg: marvell.com X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2019-05-24_07:, , signatures=0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190524_122521_205152_2E14844C X-CRM114-Status: GOOD ( 27.72 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Catalin Marinas , Will Deacon , Jayachandran C , "linux-arm-kernel@lists.infradead.org" , Suzuki K Poulose Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sun, May 19, 2019 at 02:12:44AM +0300, Aaro Koskinen wrote: > Hi, > > On Sat, May 18, 2019 at 10:19:39PM +0000, Jayachandran Chandrasekharan Nair wrote: > > On Thu, May 16, 2019 at 09:44:53PM +0300, Aaro Koskinen wrote: > > > On Wed, Feb 01, 2017 at 09:48:52AM +0000, Jayachandran C wrote: > > > > The current code puts the stopped cpus in an 'yield' instruction loop. > > > > Using a busy loop here is unnecessary, we can use the cpu_park_loop() > > > > function here to do a wfi/wfe. > > > > > > > > Signed-off-by: Jayachandran C > > > > > > Looks like this patch has been forgotten? > > > > > > I have a system where CPUs need to be put in wfi/wfe for the warm reset > > > to work, and using cpu_park_loop() would solve this. > > > > If I remember correctly (it has been a while), in my testing I saw that > > the wfi does not block after a while since interrupts are pending. > > Most likely that timer interrupts will still be enabled. > > Right, this is correct; I also observed the same in my testing. > > > We might need some code to reset/disable the GIC interface for the CPU > > before parking. > > I solved this by doing the global GIC disable in the firmware PSCI reset > function code. So from Linux side cpu_park_loop() is enough, and already > this patch is an improvement. Ideally, I think the GIC driver has to be updated to turn off the interrupts to the CPU before we get to this point in the code. There are some power management and hotplug notifiers already in the GIC driver, I wonder if it is possible to take care of this too. Since Linux turns on the interrupts, it would be better if Linux turns them off too, rather than relying on the platform to do it. JC _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel