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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A19A4C4332F for ; Mon, 28 Nov 2022 16:58:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232016AbiK1Q63 (ORCPT ); Mon, 28 Nov 2022 11:58:29 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44066 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231925AbiK1Q6J (ORCPT ); Mon, 28 Nov 2022 11:58:09 -0500 Received: from mx0b-002e3701.pphosted.com (mx0b-002e3701.pphosted.com [148.163.143.35]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id ACD0012AF7; Mon, 28 Nov 2022 08:58:00 -0800 (PST) Received: from pps.filterd (m0134425.ppops.net [127.0.0.1]) by mx0b-002e3701.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 2ASGbpE4027841; Mon, 28 Nov 2022 16:57:43 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=hpe.com; h=from : to : cc : subject : date : message-id : references : in-reply-to : content-type : content-transfer-encoding : mime-version; s=pps0720; bh=FObPKKabfnw+zUHRRuyWjF7/0t66BQmgmBJeN0pJ+AI=; b=cGhf3Nvf3XswMcNhD4HcSekVzb7sq/wIHQli1cJYDNTlmKPcd1MZYcXFmn+/ULuRXDtW Z+dA1nKmPG3Uu5hHhr3ENfYx4BpQygzJ2AlV2mTucjGDt4HiWlLQQhyK4zIjqUuUXIjY jAy4JE1uaE0SqkR+o/br2DWCbsehnaw7OS8Y7kuO7x4NbVUMe8PmUUz3Fzm8FyJetwlB RgTtpZ9doCOUDRmOQDt6clnJNBKgaH7R2MwH9o8W1jtSA2/to9o/MmtRouxkZNQ2sHCA rrhOvJaHJGfln0mrTp59sfp9oybZ9hO0Jjq7nJHY2V3s4w9gH9PM4gmpI05N9a1exyH3 dQ== Received: from p1lg14879.it.hpe.com (p1lg14879.it.hpe.com [16.230.97.200]) by mx0b-002e3701.pphosted.com (PPS) with ESMTPS id 3m50nur4xs-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 28 Nov 2022 16:57:42 +0000 Received: from p1wg14926.americas.hpqcorp.net (unknown [10.119.18.115]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by p1lg14879.it.hpe.com (Postfix) with ESMTPS id A8EA32FCE7; Mon, 28 Nov 2022 16:57:40 +0000 (UTC) Received: from p1wg14923.americas.hpqcorp.net (10.119.18.111) by p1wg14926.americas.hpqcorp.net (10.119.18.115) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.15; Mon, 28 Nov 2022 04:57:26 -1200 Received: from P1WG14918.americas.hpqcorp.net (16.230.19.121) by p1wg14923.americas.hpqcorp.net (10.119.18.111) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.15 via Frontend Transport; Mon, 28 Nov 2022 04:57:26 -1200 Received: from NAM11-BN8-obe.outbound.protection.outlook.com (192.58.206.38) by edge.it.hpe.com (16.230.19.121) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.986.15; Mon, 28 Nov 2022 16:57:25 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=SDSus599kLoswdxKIZdGiIat7OHwh+c++3B28ozO5w3v75QFaBrURReKyUTaUS3m+PtTTPOhJO//2nKg3Un/1NAOp3lq/pFQis82b7ZrP5oyYKAe4FqTJQULov88WHa/b2BiSXLaB9xiqZsGkd0LKfxnMvtGrQ17UnrggCY+cPe98xF8W8yAKayggI1xuY7yUx8nNobDH2vuj94TUU9KBkO1i2rYJRsIQa0mAojEgeJZszrXd5IGviUG5+cJNdSujBj/7JgVjOYrTt1YR9cQBOMn2ZKEFQYTD3tKFcSUCg1VkIIvwosLyn825XuMd0+hsyoAPQDEBgc1k8t7qoxp0Q== 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=FObPKKabfnw+zUHRRuyWjF7/0t66BQmgmBJeN0pJ+AI=; b=VYC5hI/KthIXTM0lM1L3pu5lu8+Wnnl6ebpzsUi7tP0F8HJlXg/25j74AYT9AWx/RNqTHMhzZoLCsaIoZflAi9geHydtk3Gk8uBp49qi0OUoDFkzaqcB8AKxeP2G4YLoTWqEnoWliuaQDCI7ncYdYy1OH8OSOIfWUyH5yeGPjNVl/2ZW+0qMtK/qBWPo1Tq6uqz59tTL4+LTkstV2ItpNKraJSPkezPQHMWgDWweX5IAz/2iUZKEANx4eECbZhE7MD89IAPxvgcivCnqlmX0pYSIUZ0d5P1Iub8Es1gfbaLNF175C8oKvEtjABetCKWlAlXhs3NN78maMfm4E99szg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=hpe.com; dmarc=pass action=none header.from=hpe.com; dkim=pass header.d=hpe.com; arc=none Received: from MW5PR84MB1842.NAMPRD84.PROD.OUTLOOK.COM (2603:10b6:303:1c4::18) by PH0PR84MB1810.NAMPRD84.PROD.OUTLOOK.COM (2603:10b6:510:161::5) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5857.21; Mon, 28 Nov 2022 16:57:19 +0000 Received: from MW5PR84MB1842.NAMPRD84.PROD.OUTLOOK.COM ([fe80::5511:bd85:6961:816]) by MW5PR84MB1842.NAMPRD84.PROD.OUTLOOK.COM ([fe80::5511:bd85:6961:816%9]) with mapi id 15.20.5857.023; Mon, 28 Nov 2022 16:57:19 +0000 From: "Elliott, Robert (Servers)" To: Herbert Xu , Ard Biesheuvel CC: "Jason A. Donenfeld" , "davem@davemloft.net" , "tim.c.chen@linux.intel.com" , "ap420073@gmail.com" , "David.Laight@aculab.com" , "ebiggers@kernel.org" , "linux-crypto@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH v4 10/24] crypto: x86/poly - limit FPU preemption Thread-Topic: [PATCH v4 10/24] crypto: x86/poly - limit FPU preemption Thread-Index: AQHY+XHqfLLvXNGxcESumjNg7U4Mn65BZh+AgA36OwCAAAUngIAAAQwAgADfYdk= Date: Mon, 28 Nov 2022 16:57:19 +0000 Message-ID: References: <20221103042740.6556-1-elliott@hpe.com> <20221116041342.3841-1-elliott@hpe.com> <20221116041342.3841-11-elliott@hpe.com> In-Reply-To: Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-publictraffictype: Email x-ms-traffictypediagnostic: MW5PR84MB1842:EE_|PH0PR84MB1810:EE_ x-ms-office365-filtering-correlation-id: d96abbb4-9d86-4be3-ed7d-08dad1619c5f 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:MW5PR84MB1842.NAMPRD84.PROD.OUTLOOK.COM;PTR:;CAT:NONE;SFS:(13230022)(376002)(396003)(366004)(39860400002)(136003)(346002)(451199015)(2906002)(83380400001)(41300700001)(5660300002)(8936002)(7416002)(52536014)(186003)(33656002)(86362001)(55016003)(122000001)(38100700002)(38070700005)(82960400001)(478600001)(54906003)(316002)(26005)(110136005)(9686003)(7696005)(6506007)(71200400001)(8676002)(66946007)(64756008)(76116006)(66446008)(4326008)(66476007)(66556008);DIR:OUT;SFP:1102; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?LrwP+9P/4ZyeogOf5Eha8cYZ15QU+w25rw/lI6DK787Z2QtLxSD83+R3ruAF?= =?us-ascii?Q?eXdJ5Z+FCf7EhKZtXqyvaBKC66tB75P+w7PVmvTR4tETuI48jRi8Moy68f4j?= =?us-ascii?Q?STqNSbw6wnlIgTGVLthRq2mpIRnh9nNJRhYzOJ3RsiiFGTRcxnZBaQ4aIByb?= =?us-ascii?Q?SuZSLMsHzsyitFEK7z7gT0/rN/hyR3BKFWpR4qkxlH8sEEFGLwvbUbqrjt/2?= =?us-ascii?Q?JUieicdj5zopuFW/D9h8Y6iGfYkbG7voZU2prHhfrdwAFu7P3IgX3/1Ot0d/?= =?us-ascii?Q?tbJW4qVg21H/jO7clWiDpbrt3JIXLfCjrGELLq7BfUTe4prLjKq4fXbJca6p?= =?us-ascii?Q?NGaEeze3DZYWZIpGIyk9/dfHgWQIAa3us9BLsbhThPu1HvOYoPVetnXE0AU4?= =?us-ascii?Q?A7p2H+DJ/7F7dslQi9N/yyhurZlYXutq+/C/EEftrXAu9ltVMikHg6wm7zU/?= =?us-ascii?Q?lSy7F2fMMlxys24cW1qopAVQsAKgKnNxa9gzuLziq3D/DrK5S/0Uwg+/jgQ4?= =?us-ascii?Q?p42gxWqeTTZI8ZUjU0gqYlrR0Lo50ZvVKW9gGLyAmsOsMF5wdjIGsVLZS6TL?= =?us-ascii?Q?a4LlZ/ZKENujzZqc5cWkJ9COrNMbuiPmC0JBc2bE/y0hT5ZpC1xWPbEZ+wk0?= =?us-ascii?Q?IstuQ3OmyaV/MGQxPMgoy4J0eZjf4rRXbf91i3QjUv5VechztB/zGVbkg3z9?= =?us-ascii?Q?A8So0+Bx30q3ttj6iKLEhxSb3NbfmDh6/nSGS6MrEfh71Jb7fqUC8cSb7aNU?= =?us-ascii?Q?Jsc3LfdT/frZJ7LYRoBfT6IISHZyhkfQ9ERoiroYS0cGzqLP/Vit3LsRZwQ6?= =?us-ascii?Q?4BpxYzohjeWedo8/U3hRH4NyRoZlhSHTIxUG3uQkO5o9TN5cNdqd158z5BCC?= =?us-ascii?Q?vi9I+CcDntduPfkm/QdeMtDziSXmuaKf3YpYlTpAxXUUaLzycu+LLq9TWyY4?= =?us-ascii?Q?x+OW2TbsPn66kKdgOGWW70UvbRu9o64MCXHGUW7NybJ3LMg15zKcj6aY3cmx?= =?us-ascii?Q?Bngg/tL43qZg7rR9o/jrgUIcrLHWc28VStEfvUZcvszGnBldc7yBuCO00o8G?= =?us-ascii?Q?KxugP4r1UmeK86CJS3XEF/H2NtKwM7R1jB68MhyyqLasr+6L24N43NLsoajw?= =?us-ascii?Q?YvUx+Na9Is3mSGkpHn/6J07cu0GDzyra+ucDs4UzvnRpvj/dEJHVZtPkmUtc?= =?us-ascii?Q?BpgkhxC2biEmY8yrpq8SxZphpXtb13FDJMlWYTj3S5fyijf9PeondKZG++W1?= =?us-ascii?Q?T8Q8g2tT4U/1exZpMJbQ+6aVQAFX5FeLrWtdBX/YgRX2BD/OCfXCMDBdUTHV?= =?us-ascii?Q?eC5hKJi+MOwaqV7WOgFahv8MrRZv6UH82VIjQRNo/IwQ8QvpSV/h0LraPDQo?= =?us-ascii?Q?vZ+EpyctSbvasXO82UGL/7/rRSRnuciENi+JJNwD0q2Tvc/DmokB7kK9JOfF?= =?us-ascii?Q?zYJQPrUkpWD9RJLqT0M59DBM2MHdga7da4orW6UTEbBogoJ0wQfIR62KoIgJ?= =?us-ascii?Q?Fc8CsfBASG76zlsQEAhXyFyx2itth9/YNuoJOBWxDYOdJM8fpPOdBTu8ACka?= =?us-ascii?Q?5Ainskbp+RqwjZn6sEw=3D?= Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: MW5PR84MB1842.NAMPRD84.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-Network-Message-Id: d96abbb4-9d86-4be3-ed7d-08dad1619c5f X-MS-Exchange-CrossTenant-originalarrivaltime: 28 Nov 2022 16:57:19.1599 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 105b2061-b669-4b31-92ac-24d304d195dc X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: kapwlUOMdFvgV37uxn07wGrDnhWo/S4bjDt8MGfaeBPaMwt4nN+KuTgi288HJIuw X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR84MB1810 X-OriginatorOrg: hpe.com X-Proofpoint-ORIG-GUID: eSFy8vhXeCa6zYoqejnMm7vEz4uodLIq X-Proofpoint-GUID: eSFy8vhXeCa6zYoqejnMm7vEz4uodLIq X-HPE-SCL: -1 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.219,Aquarius:18.0.895,Hydra:6.0.545,FMLib:17.11.122.1 definitions=2022-11-28_15,2022-11-28_02,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 suspectscore=0 mlxscore=0 phishscore=0 priorityscore=1501 impostorscore=0 mlxlogscore=999 malwarescore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2210170000 definitions=main-2211280125 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 25, 2022 at 09:59:17AM +0100, Ard Biesheuvel wrote: > On arm64, this is implemented in an assembler macro 'cond_yield' so we > don't need to preserve/restore the SIMD state state at all if the > yield is not going to result in a call to schedule(). For example, the > SHA3 code keeps 400 bytes of state in registers, which we don't want > to save and reload unless needed. (5f6cb2e617681 'crypto: > arm64/sha512-ce - simplify NEON yield') That sounds like the optimal approach. There is a cost to unnecessary kernel_fpu_begin()/end() calls - increasing their usage in the x86 sha512 driver added 929 us during one boot. The cond_yield check is just a few memory reads and conditional branches. I see that is built on the asm-offsets.c technique mentioned by Dave Hansen in the x86 aria driver thread. > Note that it is only used in shash implementations, given that they > are the only ones that may receive unbounded inputs. Although typical usage probably doesn't stress this, the length of the additional associated data presented to aead implementations is unconstrained as well. At least in x86, they can end up processing multiple megabytes in one chunk like the hash functions (if the associated data is a big buffer described by a sg list created with sg_init_one()).