From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jeff Garzik Subject: Re: [PATCH 1/2 v2] PS3: changed the way to handle tx skbs Date: Fri, 31 Aug 2007 09:59:57 -0400 Message-ID: <46D81EDD.5090807@garzik.org> References: <20070831220507.C31D.MOKUNO@sm.sony.co.jp> <20070831221800.C323.MOKUNO@sm.sony.co.jp> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: Linas Vepstas , netdev@vger.kernel.org, cbe-oss-dev@ozlabs.org, geoffrey.levand@am.sony.com, Geert Uytterhoeven To: Masakazu Mokuno Return-path: Received: from srv5.dvmed.net ([207.36.208.214]:33303 "EHLO mail.dvmed.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965255AbXHaOAB (ORCPT ); Fri, 31 Aug 2007 10:00:01 -0400 In-Reply-To: <20070831221800.C323.MOKUNO@sm.sony.co.jp> Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Masakazu Mokuno wrote: > The PS3 virtual network device requires a vlan tag in the sending packet > to select the destination device, ethernet port or wireless. > As the vlan tag field is in the middle of the passed data, > we should insert it into the packet data. > To avoid copying much of the packet data, the driver used two tx descriptors > for one tx skb; one descriptor was for sending a small static > buffer which contained vlan tag and copied header (two mac addresses), > one was for the residual data after the vlan field. > > This patch changes the way to insert the vlan tag. By changing > netdev->hard_header_len, we can make the headroom for moving mac address > fields in the skb buffer. Then we can send one tx skb with > one tx descriptor. This also gives us a tx throughut gain of approx. > 20% according to netperf results. > > Signed-off-by: Masakazu Mokuno > CC: Geoff Levand > --- > drivers/net/ps3_gelic_net.c | 140 +++++++++++++++++++------------------------- > 1 file changed, 63 insertions(+), 77 deletions(-) applied 1-2, thanks for the update