From owner-freebsd-usb@FreeBSD.ORG  Tue Dec 23 20:29:41 2008
Return-Path: <owner-freebsd-usb@FreeBSD.ORG>
Delivered-To: freebsd-usb@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id EF6C91065679
	for <freebsd-usb@freebsd.org>; Tue, 23 Dec 2008 20:29:41 +0000 (UTC)
	(envelope-from thompsa@FreeBSD.org)
Received: from pele.citylink.co.nz (pele.citylink.co.nz [202.8.44.226])
	by mx1.freebsd.org (Postfix) with ESMTP id B439F8FC26
	for <freebsd-usb@freebsd.org>; Tue, 23 Dec 2008 20:29:41 +0000 (UTC)
	(envelope-from thompsa@FreeBSD.org)
Received: from localhost (localhost [127.0.0.1])
	by pele.citylink.co.nz (Postfix) with ESMTP id E2536FEF7;
	Wed, 24 Dec 2008 08:56:02 +1300 (NZDT)
X-Virus-Scanned: Debian amavisd-new at citylink.co.nz
Received: from pele.citylink.co.nz ([127.0.0.1])
	by localhost (pele.citylink.co.nz [127.0.0.1]) (amavisd-new, port 10024)
	with ESMTP id wdxicd-ngpFn; Wed, 24 Dec 2008 08:55:59 +1300 (NZDT)
Received: from citylink.fud.org.nz (unknown [202.8.44.45])
	by pele.citylink.co.nz (Postfix) with ESMTP;
	Wed, 24 Dec 2008 08:55:59 +1300 (NZDT)
Received: by citylink.fud.org.nz (Postfix, from userid 1001)
	id 0C80011430; Wed, 24 Dec 2008 08:55:59 +1300 (NZDT)
Date: Tue, 23 Dec 2008 11:55:58 -0800
From: Andrew Thompson <thompsa@FreeBSD.org>
To: Hans Petter Selasky <hselasky@c2i.net>
Message-ID: <20081223195558.GL89448@citylink.fud.org.nz>
References: <20081223175911.GZ1176@hoeg.nl>
	<200812231956.21666.hselasky@c2i.net>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <200812231956.21666.hselasky@c2i.net>
User-Agent: Mutt/1.5.17 (2007-11-01)
Cc: Ed Schouten <ed@80386.nl>, freebsd-usb@freebsd.org
Subject: Re: Giant on serial devices in USB2?
X-BeenThere: freebsd-usb@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: FreeBSD support for USB <freebsd-usb.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-usb>,
	<mailto:freebsd-usb-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-usb>
List-Post: <mailto:freebsd-usb@freebsd.org>
List-Help: <mailto:freebsd-usb-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-usb>,
	<mailto:freebsd-usb-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 23 Dec 2008 20:29:42 -0000

On Tue, Dec 23, 2008 at 07:56:21PM +0100, Hans Petter Selasky wrote:
> On Tuesday 23 December 2008, Ed Schouten wrote:
> > Hello HPS, others,
> >
> > I was just running a grep on the USB2 code and saw the following:
> >
> > $ grep -r Giant sys/dev/usb2/serial | wc -l
> >       70
> >
> > WHat's the exact reason USB2 still uses Giant on TTY related drivers?
> > Couldn't it just use the per-TTY mutex? If not, maybe it should create a
> > custom system-wide mutex, instead of using Giant?
> >
> > Yours,
> 
> Hi,
> 
> I don't have all those USB devices at hand, so I simply cannot test if the 
> driver still works without Giant.
> 
> BTW: It should be trivial to remove Giant from the drivers. I think Andrew 
> Thompson has already done some drivers Giant-free.

Its just a mechanical change, it works fine for the couple of driver I
have converted.

Andrew