From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by dpdk.space (Postfix) with ESMTP id CC63EA0AC5 for ; Wed, 1 May 2019 16:56:54 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id DE6262BC1; Wed, 1 May 2019 16:56:53 +0200 (CEST) Received: from EUR04-HE1-obe.outbound.protection.outlook.com (mail-eopbgr70077.outbound.protection.outlook.com [40.107.7.77]) by dpdk.org (Postfix) with ESMTP id 1AA132BAE for ; Wed, 1 May 2019 16:56:51 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=armh.onmicrosoft.com; s=selector1-arm-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=nqLjvQqB6ANLKJMyDaUaMxBpt/Xn0dnXBpwgFYhpZY8=; b=ZxWknLGCbiIpMQNv7cCzgvLsiU8p3ViRKGLUEnB2FPq3Vyw9P8AeWIULEEVQDdv3HA5N7fTdPh09vqD2qmEd0Rv6EstnUh2Ke2Oaz/dRwIdsdL8SmZ//wnxNw4VKe6a+ohBaSlP8XwKw7tGGRYRhjZ6k0Zw0Bjsahla3jNfawxo= Received: from VE1PR08MB5149.eurprd08.prod.outlook.com (20.179.30.152) by VE1PR08MB5104.eurprd08.prod.outlook.com (20.179.30.14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.1835.15; Wed, 1 May 2019 14:56:48 +0000 Received: from VE1PR08MB5149.eurprd08.prod.outlook.com ([fe80::9b6:3403:4386:78]) by VE1PR08MB5149.eurprd08.prod.outlook.com ([fe80::9b6:3403:4386:78%2]) with mapi id 15.20.1835.018; Wed, 1 May 2019 14:56:48 +0000 From: Honnappa Nagarahalli To: Neil Horman CC: "konstantin.ananyev@intel.com" , "stephen@networkplumber.org" , "paulmck@linux.ibm.com" , "marko.kovacevic@intel.com" , "dev@dpdk.org" , "Gavin Hu (Arm Technology China)" , Dharmik Thakkar , Malvika Gupta , Honnappa Nagarahalli , nd , nd Thread-Topic: [dpdk-dev] [PATCH v9 0/4] lib/rcu: add RCU library supporting QSBR mechanism Thread-Index: AQHVABe82XMyTZzopkuFSkjHfNlwJqZWQCDQ Date: Wed, 1 May 2019 14:56:48 +0000 Message-ID: References: <20181122033055.3431-1-honnappa.nagarahalli@arm.com> <20190501035419.33524-1-honnappa.nagarahalli@arm.com> <20190501121545.GA26521@hmswarspite.think-freely.org> In-Reply-To: <20190501121545.GA26521@hmswarspite.think-freely.org> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: authentication-results: spf=none (sender IP is ) smtp.mailfrom=Honnappa.Nagarahalli@arm.com; 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DIR:OUT; SFP:1101; SCL:1; SRVR:VE1PR08MB5104; H:VE1PR08MB5149.eurprd08.prod.outlook.com; FPR:; SPF:None; LANG:en; PTR:InfoNoRecords; A:1; MX:1; received-spf: None (protection.outlook.com: arm.com does not designate permitted sender hosts) x-ms-exchange-senderadcheck: 1 x-microsoft-antispam-message-info: Cab4Vhc5ohfbsN8TklR6y32RmPbKpA1/V1ErPAWR07L+7VCRGlEDFIa9XlBFusJ/vvznTZdMmX0H0+R409xZwOkw7jATANan/X5ZrfP+yuXLorxUolxkhQQy4+VurVEFt8KDKxTR5Yy7fScvZz3UwFSdwjPdo3AuIEFsT34CEorQ8cMy3QQLmDG/v2WM2eF67gaaIzD8w9Jh3oboNV/4nbsGyCQR8BMrnLlSj4i6e1qnVovuSy3T6AzsrOfqPOJ9+mhA2A6f01/63ZVSqD0B3N+vksJYh6cArKVcsiRFOcOvlPWL+bc7qO5eXQjEa90usupSlPzIWvX+bHJFqyMbKwuD1Wl4GcBt9rHjPBVRgxEAcZy1+oOm0pbIe5Y9RktCYOJskt+spJEWRQ1dXX7QC+fsv+qsTfK8+VE1jkITY6U= Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: arm.com X-MS-Exchange-CrossTenant-Network-Message-Id: efa6a3d4-967c-43bc-d56d-08d6ce453cc3 X-MS-Exchange-CrossTenant-originalarrivaltime: 01 May 2019 14:56:48.5244 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: f34e5979-57d9-4aaa-ad4d-b122a662184d X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-Transport-CrossTenantHeadersStamped: VE1PR08MB5104 Subject: Re: [dpdk-dev] [PATCH v9 0/4] lib/rcu: add RCU library supporting QSBR mechanism X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" Message-ID: <20190501145648.a4VQljSzdKg6lGpeSEL-sjzOwqjofqBZxT7DJ-p6KZw@z> >=20 > On Tue, Apr 30, 2019 at 10:54:15PM -0500, Honnappa Nagarahalli wrote: > > Lock-less data structures provide scalability and determinism. > > They enable use cases where locking may not be allowed (for ex: > > real-time applications). > > > I know this is version 9 of the patch, so I'm sorry for the late comment,= but I > have to ask: Why re-invent this wheel? There are already several Userspa= ce Thanks Neil, for asking the question. This has been debated before. Please = refer to [2] for more details. liburcu [1] was explored as it seemed to be familiar to others in the commu= nity . I am not aware of any other library. There are unique requirements in DPDK and there is still scope for improvem= ent from what is available. I have explained this in the cover letter witho= ut making a direct comparison to liburcu. May be it is worth tweaking the d= ocumentation to call this out explicitly. [1] https://liburcu.org/ [2] http://mails.dpdk.org/archives/dev/2018-November/119875.html > RCU libraries that are mature and carried by Linux and BSD distributions. > Why would we throw another one into DPDK instead of just using whats > already available, mature and stable? >=20 > Neil