From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH v2] b44: fix misalignment and wasted space in rx handling Date: Fri, 09 Jan 2009 23:08:17 -0800 (PST) Message-ID: <20090109.230817.36393679.davem@davemloft.net> References: <4967459D.3070207@openwrt.org> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, mb@bu3sch.de To: nbd@openwrt.org Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:56608 "EHLO sunset.davemloft.net" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1752221AbZAJHIQ (ORCPT ); Sat, 10 Jan 2009 02:08:16 -0500 In-Reply-To: <4967459D.3070207@openwrt.org> Sender: netdev-owner@vger.kernel.org List-ID: From: Felix Fietkau Date: Fri, 09 Jan 2009 13:39:57 +0100 > Broadcom 4400 puts a header of configurable size (apparently needs > to be at least 28 bytes) in front of received packets. When handling > this, the previous code accidentally added the offset 30 *twice* for > the software and once for the hardware, thereby cancelling out the > IP alignment effect of the 30 byte padding and wasting an additional > 30 bytes of memory per packet. > > This patch fixes this problem and improves routing throughput by > about 30% on MIPS, where unaligned access is expensive. > > Signed-off-by: Felix Fietkau Applied.