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=-1.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS 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 A3D68C31680 for ; Mon, 21 Jan 2019 18:22:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6D8E720879 for ; Mon, 21 Jan 2019 18:22:15 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=Mellanox.com header.i=@Mellanox.com header.b="IuAk5eGM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727633AbfAUSWO (ORCPT ); Mon, 21 Jan 2019 13:22:14 -0500 Received: from mail-eopbgr130054.outbound.protection.outlook.com ([40.107.13.54]:30816 "EHLO EUR01-HE1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727280AbfAUSWN (ORCPT ); Mon, 21 Jan 2019 13:22:13 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Mellanox.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=A1AtMz2XGq22Mc9rSLCYkxgeVZdA6rv4jy/pxtGxBvc=; b=IuAk5eGMzxcizF0g0Oapgcu4BuzE+intRF8uwZactRFH5NiHh//pLCA2j+u+cdyvjzXXFtYLLhiYa8YK6tQOnwGJ5jceSXuYFY6Apkx0y83NhidFcYHYS087iLeZUG/1RxLVPs/sEyAWX3Ev0LdYpWtTsmjWf/bcD9BEWJmEIo0= Received: from HE1PR05MB4601.eurprd05.prod.outlook.com (20.176.163.138) by HE1PR05MB3370.eurprd05.prod.outlook.com (10.170.243.152) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1537.29; Mon, 21 Jan 2019 18:22:08 +0000 Received: from HE1PR05MB4601.eurprd05.prod.outlook.com ([fe80::75a0:a89d:1227:7ed3]) by HE1PR05MB4601.eurprd05.prod.outlook.com ([fe80::75a0:a89d:1227:7ed3%5]) with mapi id 15.20.1537.031; Mon, 21 Jan 2019 18:22:08 +0000 From: Jason Gunthorpe To: Saeed Mahameed CC: Leon Romanovsky , Saeed Mahameed , "netdev@vger.kernel.org" , "linux-rdma@vger.kernel.org" , Maxim Mikityanskiy , Eran Ben Elisha Subject: Re: [PATCH mlx5-next 4/4] net/mlx5: Remove spinlock support from mlx5_write64 Thread-Topic: [PATCH mlx5-next 4/4] net/mlx5: Remove spinlock support from mlx5_write64 Thread-Index: AQHUr469Vj10XdM6C0irA9oBgVV346W2NiYAgAO8RYCAABhXAIAAAoYA Date: Mon, 21 Jan 2019 18:22:08 +0000 Message-ID: <20190121182200.GI25149@mellanox.com> References: <20190119003313.16711-1-saeedm@mellanox.com> <20190119003313.16711-5-saeedm@mellanox.com> <20190119074308.GH15600@mtr-leonro.mtl.com> <20190121164551.GF25149@mellanox.com> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-clientproxiedby: MWHPR20CA0006.namprd20.prod.outlook.com (2603:10b6:300:13d::16) To HE1PR05MB4601.eurprd05.prod.outlook.com (2603:10a6:7:99::10) authentication-results: spf=none (sender IP is ) smtp.mailfrom=jgg@mellanox.com; x-ms-exchange-messagesentrepresentingtype: 1 x-originating-ip: [174.3.196.123] x-ms-publictraffictype: Email x-microsoft-exchange-diagnostics: 1;HE1PR05MB3370;6:+rja2XQiH3a7JLySYJqWT3QRgqsU2SfyUhwu8oHFheiS4UyB51q7qwhcD2rmEkRus0tk0vldwU1ebFp1N8M6paPxv87i5RhlAtSL3Fy1XuIMhL9IVXMFZC17nlRWxEHcPGrerkivQiFRKEViidrH6/i6KPPs/Eai5RD0p6KJX9DvE89VpaK9iDwWgRBa8BgMYJfJymGjFafrpv3dPZdCxOscVdUnRtGqgOTolnEB46VE1w3A1zqoTyDpxVFq18d12RmmpR45emQMzbnaq2GmpOYoAuUifSh3WJVRFncnFKIBnDpvaoJ8yxKOFfzj/rk1DrYu7H8JVvYW8L2LpnlHW0JXyY+hT96NUJ4ig46QG/Ug4b1w14xcD+uzez9VzoE1fuE2tGLRnO7hiWWXPwW1WvSpBV4DAp6xUA4t4+L7h8usj2/IlbjxWsAZv5W0ki6wWk/tk5AMeh2s2HJ4CIvNfA==;5:HwNUhQMU6Th0ZxvmPIsdp0ZQ3h1SwMnWF/3m7oJ53rDRY5NNT/FHJY/xr+21obdESxHPfd+p68/nhGnDg1y84j5HxoqfGUuOYtPOU8pYjYjC1OQMcmNNgETvx+ALe/zkbR4udddtuN7T6L5rksrLzLWdIWNpWh2KA9TCl/znnlk6JTjJkGpBp50eDkwIHm0HifKKHsiC8Fu6OtWi1XB5hw==;7:VOsLxGBOapzo5g64ezc/DsQBIrq9qY+ksPxhEi8/hfcdDBz2e+DdQKLu/tLi/9hDvVZaRZlOFeGKVCqg812HZCHVNbfgz2qMJJIKN1PgGdEOhZD9Lrih22vw0BTgYIb8nVThXImlLeYFnwCQN4BpgA== x-ms-office365-filtering-correlation-id: b8df95bc-873a-4163-81f0-08d67fcd5a21 x-ms-office365-filtering-ht: Tenant x-microsoft-antispam: BCL:0;PCL:0;RULEID:(2390118)(7020095)(4652040)(8989299)(4534185)(4627221)(201703031133081)(201702281549075)(8990200)(5600109)(711020)(4618075)(2017052603328)(7153060)(7193020);SRVR:HE1PR05MB3370; x-ms-traffictypediagnostic: HE1PR05MB3370: x-microsoft-antispam-prvs: x-forefront-prvs: 0924C6A0D5 x-forefront-antispam-report: SFV:NSPM;SFS:(10009020)(396003)(366004)(39860400002)(376002)(136003)(346002)(199004)(189003)(36756003)(105586002)(450100002)(4326008)(71190400001)(71200400001)(66066001)(6862004)(81166006)(81156014)(106356001)(107886003)(316002)(6246003)(14454004)(1076003)(2616005)(11346002)(256004)(14444005)(486006)(446003)(476003)(478600001)(86362001)(8676002)(68736007)(102836004)(53546011)(186003)(6436002)(97736004)(3846002)(7736002)(53936002)(305945005)(386003)(6512007)(6506007)(26005)(33656002)(6486002)(93886005)(54906003)(2906002)(25786009)(52116002)(229853002)(8936002)(76176011)(6116002)(99286004);DIR:OUT;SFP:1101;SCL:1;SRVR:HE1PR05MB3370;H:HE1PR05MB4601.eurprd05.prod.outlook.com;FPR:;SPF:None;LANG:en;PTR:InfoNoRecords;A:1;MX:1; received-spf: None (protection.outlook.com: mellanox.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: k2DrwyidKnsFmaOSV/X6vAG+40mJuclvZxGrE05Jiy+v9vS8rxYSfsQVwagzZmmWoY8qGsEdOj7oP3OPQ5YVWhj362MVYUbu7LEcyinsJVS7UUpkt1n1ODokUEIEQzgsJ1Y3QjCWkXk/29k2sf/JiTJyv6DDlS1sQYJ2B+OKVy9Bq9AToM1fMYiMPyxbSUd6Y9yhQwKu0h3sn0MJkUuEkfMUd7Vs2bo60dY/nDzqeZVvWRsZp6+4gKodduRMnYPGchaCj8FoRHXH8rrDZKexYPQr5YqpeRRUgnPh4WN3jQlmPB7LeMZxBjqIpI0Dge43VqJSNoEnSZF0yq2sb+i4V6DS6PBdArDkftTHiKDXnSQ+9kZuFTu3kDcaWEp+SLO3d7lGzcwWQEM+l94dIYQ6kDql3elNUoo1HH775MYW7nA= spamdiagnosticoutput: 1:99 spamdiagnosticmetadata: NSPM Content-Type: text/plain; charset="us-ascii" Content-ID: <9A673E6E6DF7C94F93AEAD9C776FCC60@eurprd05.prod.outlook.com> Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: Mellanox.com X-MS-Exchange-CrossTenant-Network-Message-Id: b8df95bc-873a-4163-81f0-08d67fcd5a21 X-MS-Exchange-CrossTenant-originalarrivaltime: 21 Jan 2019 18:22:07.6662 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: a652971c-7d2e-4d9b-a6a4-d149256f461b X-MS-Exchange-Transport-CrossTenantHeadersStamped: HE1PR05MB3370 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Mon, Jan 21, 2019 at 10:12:58AM -0800, Saeed Mahameed wrote: > On Mon, Jan 21, 2019 at 8:46 AM Jason Gunthorpe wrote: > > > > On Sat, Jan 19, 2019 at 12:43:14AM -0700, Leon Romanovsky wrote: > > > You need to do one of two things: > > > 1. Require CONFIG_64BIT and delete this 32bit code. > > > 2. Declare global mlx5 DB spinlock and use on 32bit systems, somethin= g > > > like this: > > > #if BITS_PER_LONG =3D=3D 64 > > > __raw_writeq(*(u64 *)val, dest); > > > #else > > > spin_lock_irqsave(doorbell_lock, flags); > > > __raw_writel((__force u32) val[0], dest); > > > __raw_writel((__force u32) val[1], dest + 4); > > > spin_unlock_irqrestore(doorbell_lock, flags); > > > #endif > > > > And why is this code using the __raw_ versions? Seems wrong too... > > >=20 > for 64 and 32 as well? yes > what is wrong with the raw version ? It should only be used by arch code (or in drivers linked to a specific arch). The actual properties of the 'raw' version are arch specific and make it hard to know if the driver will work on different archs. ie some arches may not byte swap their raw accessors, or may omit barriers. Most likely this just wants to be writeq for 64 bit and writel_relaxed() & writel() for 32 bit - unless there was some reason to have used __raw versions in the first place (in which case a comment is missing). Jason