From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [net-next-2.6 PATCH 1/3] e1000e: use hardware writeback batching Date: Thu, 30 Sep 2010 21:16:57 -0700 (PDT) Message-ID: <20100930.211657.63042041.davem@davemloft.net> References: <20100930073814.13378.4212.stgit@localhost.localdomain> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, gospo@redhat.com, bphilips@novell.com, jesse.brandeburg@intel.com To: jeffrey.t.kirsher@intel.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:48260 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751086Ab0JAEQh (ORCPT ); Fri, 1 Oct 2010 00:16:37 -0400 In-Reply-To: <20100930073814.13378.4212.stgit@localhost.localdomain> Sender: netdev-owner@vger.kernel.org List-ID: From: Jeff Kirsher Date: Thu, 30 Sep 2010 00:38:49 -0700 > From: Jesse Brandeburg > > Most e1000e parts support batching writebacks. The problem with this is > that when some of the TADV or TIDV timers are not set, Tx can sit forever. > > This is solved in this patch with write flushes using the Flush Partial > Descriptors (FPD) bit in TIDV and RDTR. > > This improves bus utilization and removes partial writes on e1000e, > particularly from 82571 parts in S5500 chipset based machines. > > Only ES2LAN and 82571/2 parts are included in this optimization, to reduce > testing load. > > Signed-off-by: Jesse Brandeburg > Tested-by: Emil Tantilov > Signed-off-by: Jeff Kirsher Applied.