From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by dpdk.org (Postfix) with ESMTP id 7DFC62A5B for ; Tue, 20 Oct 2015 11:52:05 +0200 (CEST) Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga103.fm.intel.com with ESMTP; 20 Oct 2015 02:52:04 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,706,1437462000"; d="scan'208";a="797839413" Received: from irsmsx152.ger.corp.intel.com ([163.33.192.66]) by orsmga001.jf.intel.com with ESMTP; 20 Oct 2015 02:52:03 -0700 Received: from irsmsx105.ger.corp.intel.com ([169.254.7.75]) by IRSMSX152.ger.corp.intel.com ([169.254.6.38]) with mapi id 14.03.0248.002; Tue, 20 Oct 2015 10:52:02 +0100 From: "Ananyev, Konstantin" To: Stephen Hemminger , Amine Kherbouche Thread-Topic: [dpdk-dev] [dpdk-dev, PATCHv6 1/6] ethdev: enhance rte_eth_(tx|rx)q_info struct Thread-Index: AQHRCr/Es5IYI2pj1kSbOPpjQpe9OZ50IU5w Date: Tue, 20 Oct 2015 09:52:02 +0000 Message-ID: <2601191342CEEE43887BDE71AB97725836AB2B3C@irsmsx105.ger.corp.intel.com> References: <1443729293-20753-2-git-send-email-konstantin.ananyev@intel.com> <1445292384-19815-1-git-send-email-amine.kherbouche@6wind.com> <1445292384-19815-2-git-send-email-amine.kherbouche@6wind.com> <20151019154427.65ccc42b@xeon-e3> In-Reply-To: <20151019154427.65ccc42b@xeon-e3> Accept-Language: en-IE, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [163.33.239.181] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Cc: "dev@dpdk.org" Subject: Re: [dpdk-dev] [dpdk-dev, PATCHv6 1/6] ethdev: enhance rte_eth_(tx|rx)q_info struct X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 20 Oct 2015 09:52:06 -0000 > -----Original Message----- > From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Stephen Hemminger > Sent: Monday, October 19, 2015 11:44 PM > To: Amine Kherbouche > Cc: dev@dpdk.org > Subject: Re: [dpdk-dev] [dpdk-dev, PATCHv6 1/6] ethdev: enhance rte_eth_(= tx|rx)q_info struct >=20 > On Tue, 20 Oct 2015 00:06:19 +0200 > Amine Kherbouche wrote: >=20 > > + uint16_t used_desc; /**< number of used descriptors */ > > + uint16_t free_desc; /**< number of free descriptors */ >=20 > These two fields are obviously not SMP sfe. I don't think they have to be. >>From my thinking it is just a snapshot of SW state of the queue, that could= be used for statistics/watchdog/debugging purposes. > Also, they are redundant with the existing queue_count API? Yep, similar thought here: In the for Intel HW implementations: qinfo->used_desc =3D ixgbe_dev_rx_queue_count(dev, queue_id); It seems a bit redundant, as if user wants to know HW state it can call rte= _eth_rx_queue_count() directly. >>From other side: rte_eth_rx_queue_count() is quite heavyweight function, a= s it scans HW descriptors to check their status. I think it should be better to return here just a snapshot of SW state: how= many free/used RXDs are from PMD perspective (by collecting info from *_rx_queue structure, without reading actual HW re= gisters/descriptors - as you done for TX queue info). Konstantin