From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from dpdk.org (dpdk.org [92.243.14.124]) by inbox.dpdk.org (Postfix) with ESMTP id D0621A04DE; Fri, 30 Oct 2020 17:02:50 +0100 (CET) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id F0CD3C9D8; Fri, 30 Oct 2020 17:02:47 +0100 (CET) Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by dpdk.org (Postfix) with ESMTP id 0A6E6C9D3 for ; Fri, 30 Oct 2020 17:02:45 +0100 (CET) IronPort-SDR: PX4VDIymOinXrPcVWsn/DSvIg70k6B0IJIVowYviv/lE8TtLw6q06yF1UEAr2zr1VK3p1S1t1p 6keSWXhV66Ew== X-IronPort-AV: E=McAfee;i="6000,8403,9790"; a="165129506" X-IronPort-AV: E=Sophos;i="5.77,433,1596524400"; d="scan'208";a="165129506" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Oct 2020 09:02:43 -0700 IronPort-SDR: t2rknAj00hn4Tx94uCfaGc2So334tsP+p9VstyL9x36QwUZYATjYIbeQzQQJLYhiRBRduxmU1X hCilYLZb90kQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.77,433,1596524400"; d="scan'208";a="425378586" Received: from fmsmsx605.amr.corp.intel.com ([10.18.126.85]) by fmsmga001.fm.intel.com with ESMTP; 30 Oct 2020 09:02:43 -0700 Received: from fmsmsx610.amr.corp.intel.com (10.18.126.90) by fmsmsx605.amr.corp.intel.com (10.18.126.85) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Fri, 30 Oct 2020 09:02:43 -0700 Received: from fmsmsx611.amr.corp.intel.com (10.18.126.91) by fmsmsx610.amr.corp.intel.com (10.18.126.90) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5; Fri, 30 Oct 2020 09:02:42 -0700 Received: from fmsedg602.ED.cps.intel.com (10.1.192.136) by fmsmsx611.amr.corp.intel.com (10.18.126.91) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.1713.5 via Frontend Transport; Fri, 30 Oct 2020 09:02:42 -0700 Received: from NAM11-DM6-obe.outbound.protection.outlook.com (104.47.57.168) by edgegateway.intel.com (192.55.55.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.1713.5; Fri, 30 Oct 2020 09:02:42 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=F7Ro7ZLWwwviKhzFbkuz6R2u4E12y6RVFGw9kkKwLIuurodb7PAzmZ4oVt+7eHeiwUqgMxbNsryuA29YLfNClUiM4ud+Ro8mTt/1jxdjZg+7PgWqJN4Y4idILZBwPn0Z8xhbp1gIFQ5tsT/ofvbcVF8mWF48DiOuSpqKB/pi1r+KvcniD/CSP9t8JgZ4zHDt6sf9Qrn1H/jzRCmHDg9LLKaqJIpRHGwzby/BBp3NirkUWIpiVPNN2T8LSmG5tPSNDdhTREekx72yahiqoI6xuxLjjBZtOHeSc9PugMzTFo0Drh5xYkg2Nh0ITkn3l/Mz16WLkoU12xZuZiZxII58XA== 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-SenderADCheck; bh=6V67/7PiIT00tOiH13KzDu5I/QJrMwLksVWAPIMeGCc=; b=Fyz8qR5Q/mFUzJoAoAaBbqxi3Kvkwgah0wWUEPpcCXksvaSyh5S5zSv/2vI7EvzhZebGoySNIdsKAnPpNbvSR2IR1/od/IMVZEtAP9umDW+bTG01ozRrVkBDka6UGHde1CzVymgUxEYu05mZDPJmdjt1P8XtOHAYlGlxxK4cQSzJXS1jJyayFH7p7oEJCgKFUe+7/4hB+03mBYF28wphpJwe+Vz9dyPp7cXsz00QdsSLx8+c2+F28C5kIlHcwbSHP42UkTDSWei1j4zeVE2HGbERGpxok1e90JgHWGoUnrTEzFy9wTiPGBZRErkwI/NIA3nS+vASITkaXfihuZ8reg== 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 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=intel.onmicrosoft.com; s=selector2-intel-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=6V67/7PiIT00tOiH13KzDu5I/QJrMwLksVWAPIMeGCc=; b=aYeeyih08DsxL8Q9Ox8J0IBxtqm258va+n65kdojCJbXqMNm9wVzTtU1OgUgCjvtCliSxlyCOUdlyai4wSsdqGmzJdc8m9fk8BJcbacUFoBshKVseOngyIeHoGQWGHvZ+dj637jjlzMGQ8YO19iiV6kbXtqcSVZcoy54NdZQQAU= Received: from SN6PR11MB3103.namprd11.prod.outlook.com (2603:10b6:805:d7::13) by SA0PR11MB4687.namprd11.prod.outlook.com (2603:10b6:806:96::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3499.18; Fri, 30 Oct 2020 16:02:41 +0000 Received: from SN6PR11MB3103.namprd11.prod.outlook.com ([fe80::e43b:59bb:161:8349]) by SN6PR11MB3103.namprd11.prod.outlook.com ([fe80::e43b:59bb:161:8349%3]) with mapi id 15.20.3499.029; Fri, 30 Oct 2020 16:02:41 +0000 From: "McDaniel, Timothy" To: Thomas Monjalon CC: "'dev@dpdk.org'" , "Carrillo, Erik G" , "Eads, Gage" , "Van Haaren, Harry" , "'jerinj@marvell.com'" , "'david.marchand@redhat.com'" Thread-Topic: [PATCH v5 00/23] Add DLB2 PMD Thread-Index: AQHWrr6/gG0IhuLnfEaWgT4f3kKGn6mwReawgAAEmACAAAKPQA== Date: Fri, 30 Oct 2020 16:02:41 +0000 Message-ID: References: <1602958879-8558-2-git-send-email-timothy.mcdaniel@intel.com> <5348013.yrGTY7C4b0@thomas> <5792010.8yoxlyRsN9@thomas> In-Reply-To: <5792010.8yoxlyRsN9@thomas> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: dlp-product: dlpe-windows dlp-reaction: no-action dlp-version: 11.5.1.3 authentication-results: monjalon.net; dkim=none (message not signed) header.d=none;monjalon.net; dmarc=none action=none header.from=intel.com; x-originating-ip: [162.251.9.49] x-ms-publictraffictype: Email x-ms-office365-filtering-correlation-id: 45cb4368-d304-4308-065e-08d87ced3b2d x-ms-traffictypediagnostic: SA0PR11MB4687: x-ms-exchange-transport-forked: True x-microsoft-antispam-prvs: x-ms-oob-tlc-oobclassifiers: OLM:9508; x-ms-exchange-senderadcheck: 1 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: yYf9aWEUPUPdsY8NN+erDZf5CT4YSY41CEQtCp7eLUtgqRz8Njb/rJlpvTG2qA15dvLfESPzRSD5Pfzmi+D0DRHDywELE6owfv0CMJtridw3GrIn4WtUFn0FfqAllX4x3gyzKgh6uolPy+aSGjot/PCDAG1xNr/tyYrfORu+YELb8mWgQzVdTrX0TLuIQ2DF5bYt0cu0/i6NacoLwWiDXqviO82bRJfNpOSoyxhtCNt7kYj3/RziQfm57CqU8DP59eFVsjwyHVFY/v8X1U2ks00HnQFbVfDlPWzupcn16ZTQ70ridn8uWlb84BJTa3Itzbzi8ptSeKWJBKR/TYZddw== x-forefront-antispam-report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:SN6PR11MB3103.namprd11.prod.outlook.com; PTR:; CAT:NONE; SFS:(4636009)(366004)(396003)(39860400002)(346002)(376002)(136003)(83380400001)(26005)(66476007)(66446008)(64756008)(66556008)(8676002)(316002)(52536014)(76116006)(33656002)(66946007)(7696005)(9686003)(5660300002)(186003)(4326008)(54906003)(71200400001)(478600001)(86362001)(55016002)(8936002)(2906002)(6916009)(6506007)(53546011); DIR:OUT; SFP:1102; x-ms-exchange-antispam-messagedata: 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 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: SN6PR11MB3103.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 45cb4368-d304-4308-065e-08d87ced3b2d X-MS-Exchange-CrossTenant-originalarrivaltime: 30 Oct 2020 16:02:41.3585 (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: OG7sJ07UO0jyD2siu46By1TwutE/kxglODFO66AIbRzFeV0L7x3d3QvV50ju3QMps/NCFnZ/8h+8vtysAwrXeOFAVukPg4f0jZ/d+1o+Bec= X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR11MB4687 X-OriginatorOrg: intel.com Subject: Re: [dpdk-dev] [PATCH v5 00/23] Add DLB2 PMD 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" > -----Original Message----- > From: Thomas Monjalon > Sent: Friday, October 30, 2020 10:48 AM > To: McDaniel, Timothy > Cc: 'dev@dpdk.org' ; Carrillo, Erik G > ; Eads, Gage ; Van Haaren= , > Harry ; 'jerinj@marvell.com' > ; 'david.marchand@redhat.com' > > Subject: Re: [PATCH v5 00/23] Add DLB2 PMD >=20 > 30/10/2020 16:35, McDaniel, Timothy: > > From: Thomas Monjalon > > > 30/10/2020 12:58, McDaniel, Timothy: > > > > From: McDaniel, Timothy > > > > > From: Thomas Monjalon > > > > > > 30/10/2020 10:43, Timothy McDaniel: > > > > > > > - note that the code still uses its private byte-encoded vers= ions of > > > > > > > umonitor/umwait, rather than the new functions in the power > > > > > > > patch that are built on top of those intrinsics. This is in= tentional. > > > > > > > > > > > > Why? Now these intrinsics are available in the main branch. > > > > > > We should avoid duplicating such code. > > > > > > > > > > > > > > > > > > > > > > I had asked that the low level intrinsics (UMWAIT/UMONITOR) be sp= lit > out so > > > > > that DLB/DLB2 could use them instead of its own private byte-enco= ded > > > versions, > > > > > but instead we have these wrappers that call the low level intrin= sics. > Those > > > > > wrappers > > > > > introduce additional overhead that is not required for DLB/DLB2. = I have a > > > > > meeting with Ma Liang on Monday to discuss. > > > > > > > > I thought the ask of DLB was to just substitute the low level > umwait/umonitor > > > byte > > > > encoded instructions DLB has defined privately with similar byte-en= coded > > > instructions defined in the power > > > > patch. The power patch does not directly expose those, which is why= I did > not > > > update DLB/DLB2. > > > > The power patch does have the advantage of centralizing the race > avoidance > > > > logic, which is a good thing for any PMD that wishes to take advant= age of > > > umwait/umonitor. > > > > > > So you mean the overhead is a good thing? > > > > > > > Sorry for the confusion. I just misunderstood what was being asked = of DLB > in > > > regard to switching over.. That being said, > > > > I am willing to convert DLB/DLB2 to use rte_power_monitor(...) in = a future > > > patch-set. > > > > > > Why not now? > > > > > > Indeed there is a confusion and it looks like a lot of novlang > > > to exit from the situation. > > > We'll wait a clear decision with facts. > > > > > > > Hi Thomas, > > > > I have updated DLB and DLB2 to use rte_power_monitor(...), and those > patches are > > ready if you are willing to accept them and the 3 power patches. > > > > For the sake of consistency, I see the benefit of using the power patch= , even if > it is > > slightly less efficient that the DLB-specific implementation that I cur= rently > have. > > We have already encountered an empty queue, so this is no longer fast p= ath > for the PMD. >=20 > I am really concerned that the API in EAL is not the most efficient. > Why is that? Can we improve the EAL API? >=20 >From an efficiency perspective, I only noticed 2 things. 1) The size check and associated logic. This could be avoided if we had _8,= _16, _32, _64 variants instead of 1 function that handled all possibilitie= s, but even that may be a wash with branch prediction=20 2) The spinlock - but this observation was my mistake, and was flawed. I wa= s looking at the rte_power_monitor_sync(...), and not rte_power_monitor(...= ), the latter of which does not take a spinlock. In summary, I am no longer concerned about efficiency and suitability for D= LB/DLB2. Thanks, Tim