From owner-svn-src-all@FreeBSD.ORG Mon Jul 30 20:08:10 2012 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id D65CF106564A; Mon, 30 Jul 2012 20:08:10 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from bigwig.baldwin.cx (bigknife-pt.tunnel.tserv9.chi1.ipv6.he.net [IPv6:2001:470:1f10:75::2]) by mx1.freebsd.org (Postfix) with ESMTP id AC5838FC08; Mon, 30 Jul 2012 20:08:10 +0000 (UTC) Received: from jhbbsd.localnet (unknown [209.249.190.124]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 19133B97A; Mon, 30 Jul 2012 16:08:10 -0400 (EDT) From: John Baldwin To: Luigi Rizzo Date: Mon, 30 Jul 2012 14:45:45 -0400 User-Agent: KMail/1.13.5 (FreeBSD/8.2-CBSD-20110714-p17; KDE/4.5.5; amd64; ; ) References: <201207251128.q6PBSFlt052575@svn.freebsd.org> In-Reply-To: <201207251128.q6PBSFlt052575@svn.freebsd.org> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201207301445.45210.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Mon, 30 Jul 2012 16:08:10 -0400 (EDT) Cc: svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r238765 - head/sys/dev/e1000 X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 30 Jul 2012 20:08:10 -0000 On Wednesday, July 25, 2012 7:28:15 am Luigi Rizzo wrote: > Author: luigi > Date: Wed Jul 25 11:28:15 2012 > New Revision: 238765 > URL: http://svn.freebsd.org/changeset/base/238765 > > Log: > Use legacy interrupts as a default. This gives up to 10% speedup > when used in qemu (and this driver is for non-PCIe cards, > so probably its largest use is in virtualized environments). > > Approved by: Jack Vogel > MFC after: 3 days Why not make this a tunable or some such? You could even have it only use the legacy handler under qemu easily enough. There's no reason this has to be a compile-time option. This is almost certainly slower on real hardware where this is important to work around dubious Intel Host-PCI bridges that result in aliased USB interrupts for every em(4) interrupt. -- John Baldwin