From owner-svn-src-all@FreeBSD.ORG Tue Nov 15 21:27:16 2011 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id E068B106564A; Tue, 15 Nov 2011 21:27:16 +0000 (UTC) (envelope-from hselasky@c2i.net) Received: from swip.net (mailfe09.c2i.net [212.247.155.2]) by mx1.freebsd.org (Postfix) with ESMTP id B76C68FC14; Tue, 15 Nov 2011 21:27:15 +0000 (UTC) X-T2-Spam-Status: No, hits=2.5 required=5.0 tests=ALL_TRUSTED, BAYES_99 Received: from [188.126.198.129] (account mc467741@c2i.net HELO laptop002.hselasky.homeunix.org) by mailfe09.swip.net (CommuniGate Pro SMTP 5.2.19) with ESMTPA id 29290341; Tue, 15 Nov 2011 22:27:13 +0100 From: Hans Petter Selasky To: mdf@freebsd.org Date: Tue, 15 Nov 2011 22:24:27 +0100 User-Agent: KMail/1.13.5 (FreeBSD/8.2-STABLE; KDE/4.4.5; amd64; ; ) References: <201111152048.pAFKmvNC016452@svn.freebsd.org> In-Reply-To: X-Face: *nPdTl_}RuAI6^PVpA02T?$%Xa^>@hE0uyUIoiha$pC:9TVgl.Oq,NwSZ4V" =?iso-8859-1?q?=7CLR=2E+tj=7Dg5=0A=09=25V?=,x^qOs~mnU3]Gn; cQLv&.N>TrxmSFf+p6(30a/{)KUU!s}w\IhQBj}[g}bj0I3^glmC( =?iso-8859-1?q?=0A=09=3AAuzV9=3A=2EhESm-x4h240C=609=3Dw?= MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201111152224.27868.hselasky@c2i.net> Cc: "svn-src-head@freebsd.org" , "svn-src-all@freebsd.org" , "src-committers@freebsd.org" Subject: Re: svn commit: r227541 - head/sys/dev/usb/controller 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: Tue, 15 Nov 2011 21:27:17 -0000 On Tuesday 15 November 2011 22:21:31 mdf@freebsd.org wrote: > On Tue, Nov 15, 2011 at 1:20 PM, wrote: > > On Tue, Nov 15, 2011 at 1:02 PM, Hans Petter Selasky wrote: > >> For USB compliant operation, the USB stack requires hz to be greater or > >> equal to 250 hz, to put it like that. Mostly a requirement in USB > >> gadget/device mode. > > > > Really? That's news to me. Is that documented somewhere? I know we > > still use hz=100 internally, but we're on stable/7 still so not using > > the new USB stack yet. > > ... and I also just remembered that I have seen recommendations that, > when FreeBSD is used as a virtual machine, hz should be set to 100 so > that the virtual interrupt overhead is reduced. Those two > recommendations are at odds with each other. USB in virtual machines is a completely different story. All the timing critical stuff is handled by the real USB host operating system. The OS inside the VM just has to respond to some "virtual" USB events. Timing does not matter very much as far as I'm aware. --HPS