From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Fastabend Subject: Re: [net-2.6 PATCH 1/2] net: dcbnl: remove redundant DCB_CAP_DCBX_STATIC bit Date: Mon, 24 Jan 2011 07:52:48 -0800 Message-ID: <4D3DA050.3020006@intel.com> References: <20110122023512.4239.40379.stgit@jf-dev1-dcblab> <4D3A465F.8020809@intel.com> <1295801600.25104.13.camel@lb-tlvb-shmulik.il.broadcom.com> <4D3D123F.40700@intel.com> <1295882871.25104.20.camel@lb-tlvb-shmulik.il.broadcom.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: "davem@davemloft.net" , "netdev@vger.kernel.org" To: Shmulik Ravid Return-path: Received: from mga09.intel.com ([134.134.136.24]:48301 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753281Ab1AXPwt (ORCPT ); Mon, 24 Jan 2011 10:52:49 -0500 In-Reply-To: <1295882871.25104.20.camel@lb-tlvb-shmulik.il.broadcom.com> Sender: netdev-owner@vger.kernel.org List-ID: On 1/24/2011 7:27 AM, Shmulik Ravid wrote: > > On Sun, 2011-01-23 at 21:46 -0800, John Fastabend wrote: >> On 1/23/2011 8:53 AM, Shmulik Ravid wrote: >>> >>> On Fri, 2011-01-21 at 18:52 -0800, John Fastabend wrote: >>>> On 1/21/2011 6:35 PM, John Fastabend wrote: >>>>> Remove redundant DCB_CAP_DCBX_STATIC bit in DCB capabilities >>>>> >>>>> Setting this bit indicates that no embedded DCBx engine is >>>>> present and the hardware can not be configured. This is the >>>>> same as having none of the DCB capability flags set or simply >>>>> not implementing the dcbnl ops at all. >>>>> >>>>> This patch removes this bit. The bit has not made a stable >>>>> release yet so removing it should not be an issue with >>>>> existing apps. >>>>> >>>>> Signed-off-by: John Fastabend >>>>> CC: Shmulik Ravid >>>>> --- >>>>> >>>> Dave, Please drop this patch sorry for the noise. [...] >> We have an advertise bit in userspace that can be set and cleared to >> do something similar for host based agents. I think for pg and application >> data you can get the same behavior by setting the device to not willing. >> > True, but this requires a proper DCBx peer. The STATIC option is a bit > stronger. At least in the PG case the CEE spec says the local configuration should be used[1]. Application is a bit more vague in my opinion[2]. > >> However for PFC it could potentially be useful. But how would the >> user set this mode? This is a capabilities bit indicating the device >> supports this. Is there a way to subsequently put the device in this >> mode? > You can set this mode by specifying this attribute in the set_dcbx > operation. The input to set_dcbx should be a subset of the advertised > dcbx attributes. > OK This works for me Shmulik thanks for the explanation. [1] 3.1.4. http://www.ieee802.org/1/files/public/docs2008/az-wadekar-dcbx-capability-exchange-discovery-protocol-1108-v1.01.pdf [2] 3.3.2. http://www.ieee802.org/1/files/public/docs2008/az-wadekar-dcbx-capability-exchange-discovery-protocol-1108-v1.01.pdf