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 37FB6A04C8; Fri, 18 Sep 2020 10:35:58 +0200 (CEST) Received: from [92.243.14.124] (localhost [127.0.0.1]) by dpdk.org (Postfix) with ESMTP id 4B5411D919; Fri, 18 Sep 2020 10:35:57 +0200 (CEST) Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by dpdk.org (Postfix) with ESMTP id DC6C11D918 for ; Fri, 18 Sep 2020 10:35:55 +0200 (CEST) IronPort-SDR: RgqmEVoMiIlOJq4T+XxweCvl6Ucm3Z8LCa1TL6bUxRCkp+4wfrdswEYekZvGmctWsuFVixTRaL ELHeWLq0cEIw== X-IronPort-AV: E=McAfee;i="6000,8403,9747"; a="157274231" X-IronPort-AV: E=Sophos;i="5.77,274,1596524400"; d="scan'208";a="157274231" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Sep 2020 01:35:52 -0700 IronPort-SDR: 3v0Zn6IuewOzaxNunV+Qk8vPoKdbM4BJN6AliHfCdWMiQBqjjDktoX0gkOymaYMKWXn2N9sHWP 5rlaI9uarK6A== X-IronPort-AV: E=Sophos;i="5.77,274,1596524400"; d="scan'208";a="508782661" Received: from bricha3-mobl.ger.corp.intel.com ([10.249.147.177]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-SHA; 18 Sep 2020 01:35:49 -0700 Date: Fri, 18 Sep 2020 09:35:44 +0100 From: Bruce Richardson To: Honnappa Nagarahalli Cc: "Kinsella, Ray" , Ciara Power , "dev@dpdk.org" , Neil Horman , nd Message-ID: <20200918083544.GB1583@bricha3-MOBL.ger.corp.intel.com> References: <20200807155859.63888-1-ciara.power@intel.com> <20200827161304.32300-1-ciara.power@intel.com> <20200827161304.32300-2-ciara.power@intel.com> <20200904084518.GA1627@bricha3-MOBL.ger.corp.intel.com> <188b3510-f8da-50d8-8a31-ca48d1ad8448@ashroe.eu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [dpdk-dev] [PATCH v2 01/17] eal: add max SIMD bitwidth 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" On Fri, Sep 18, 2020 at 02:13:02AM +0000, Honnappa Nagarahalli wrote: > > > > > > > >>> > > >> > diff --git a/lib/librte_eal/include/rte_eal.h > > >> b/lib/librte_eal/include/rte_eal.h > > >>>> index ddcf6a2e7a..8148f650f2 100644 > > >>>> --- a/lib/librte_eal/include/rte_eal.h > > >>>> +++ b/lib/librte_eal/include/rte_eal.h > > >>>> @@ -43,6 +43,13 @@ enum rte_proc_type_t { > > >>>> RTE_PROC_INVALID > > >>>> }; > > >>>> > > >>>> +enum rte_max_simd_t { > > >>> We could add a RTE_MAX_SIMD = 0. Arm platforms can use this to > > >>> choose > > >> SVE. > > >>> > > >> > > >> Is zero the best value for this? Would setting it to MAX_INT or some > > >> other big number be better, in terms of comparisons operations, or > > >> does that just not apply at all with SVE? > > > I suggested zero as the bitwidth can be specified from the command line. It > > would be much easier to input zero vs other number. > > > > Right, but it doesn't end up being that intuitive as interface > > 0 is enabled, 64 is not, 128 is enabled etc .... > > > > Suggest we use a max 16bit integer as 0xFFFF? > I think there are 2 things here: > 1) What is the internal representation (for ex: the value of the enum)? Here assigning 0xFFFF should be fine. > 2) The input value at the command line. Is it possible to say that, if the user does not provide anything, then we set the option as 0xFFFF? This would mean that SVE would be used by default on Arm platforms (which is ok for me). > Make sense. That all is perfectly doable because the initial default value is set per architecture.