From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by dpdk.org (Postfix) with ESMTP id 31AE1B3D6 for ; Fri, 12 Jun 2015 03:49:43 +0200 (CEST) Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga101.jf.intel.com with ESMTP; 11 Jun 2015 18:49:42 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,598,1427785200"; d="scan'208";a="745303221" Received: from pgsmsx102.gar.corp.intel.com ([10.221.44.80]) by orsmga002.jf.intel.com with ESMTP; 11 Jun 2015 18:49:41 -0700 Received: from shsmsx151.ccr.corp.intel.com (10.239.6.50) by PGSMSX102.gar.corp.intel.com (10.221.44.80) with Microsoft SMTP Server (TLS) id 14.3.224.2; Fri, 12 Jun 2015 09:49:28 +0800 Received: from shsmsx102.ccr.corp.intel.com ([169.254.2.165]) by SHSMSX151.ccr.corp.intel.com ([169.254.3.168]) with mapi id 14.03.0224.002; Fri, 12 Jun 2015 09:49:27 +0800 From: "Ouyang, Changchun" To: Stephen Hemminger Thread-Topic: [PATCH 5/5] virtio: fix ring size negotiation Thread-Index: AQHQpF7P6DItCCuSGkaxt4Q+G5TFwZ2oGzFw Date: Fri, 12 Jun 2015 01:49:27 +0000 Message-ID: References: <1434038007-8964-1-git-send-email-stephen@networkplumber.org> <1434038007-8964-6-git-send-email-stephen@networkplumber.org> In-Reply-To: <1434038007-8964-6-git-send-email-stephen@networkplumber.org> Accept-Language: zh-CN, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Cc: "dev@dpdk.org" , Stephen Hemminger Subject: Re: [dpdk-dev] [PATCH 5/5] virtio: fix ring size negotiation 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: Fri, 12 Jun 2015 01:49:43 -0000 > -----Original Message----- > From: Stephen Hemminger [mailto:stephen@networkplumber.org] > Sent: Thursday, June 11, 2015 11:53 PM > To: Ouyang, Changchun > Cc: dev@dpdk.org; Stephen Hemminger; Stephen Hemminger > Subject: [PATCH 5/5] virtio: fix ring size negotiation >=20 > From: Stephen Hemminger >=20 > Negotate the virtio ring size. The host may allow for very large rings bu= t > application may only want a smaller ring. > Conversely, if the number of descriptors requested exceeds the virtio hos= t > queue size, then just silently use the smaller host size. >=20 > This fixes issues with virtio in non-QEMU envirionments. > For example Google Compute Engine allows up to 16K elements in ring. >=20 > Signed-off-by: Stephen Hemminger Acked-by: Changchun Ouyang