From owner-freebsd-arch@FreeBSD.ORG  Mon Mar 31 18:02:48 2003
Return-Path: <owner-freebsd-arch@FreeBSD.ORG>
Delivered-To: freebsd-arch@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 03EE737B401
	for <freebsd-arch@freebsd.org>; Mon, 31 Mar 2003 18:02:48 -0800 (PST)
Received: from duke.cs.duke.edu (duke.cs.duke.edu [152.3.140.1])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 3D10143FB1
	for <freebsd-arch@freebsd.org>; Mon, 31 Mar 2003 18:02:47 -0800 (PST)
	(envelope-from gallatin@cs.duke.edu)
Received: from grasshopper.cs.duke.edu (grasshopper.cs.duke.edu
	[152.3.145.30])
	by duke.cs.duke.edu (8.12.9/8.12.9) with ESMTP id h3122kMS005442
	(version=TLSv1/SSLv3 cipher=EDH-RSA-DES-CBC3-SHA bits=168 verify=NO)
	for <freebsd-arch@freebsd.org>; Mon, 31 Mar 2003 21:02:46 -0500 (EST)
Received: (from gallatin@localhost)
	by grasshopper.cs.duke.edu (8.11.6/8.9.1) id h3122f727891;
	Mon, 31 Mar 2003 21:02:41 -0500 (EST)
	(envelope-from gallatin@cs.duke.edu)
From: Andrew Gallatin <gallatin@cs.duke.edu>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Message-ID: <16008.62273.582001.784737@grasshopper.cs.duke.edu>
Date: Mon, 31 Mar 2003 21:02:41 -0500 (EST)
To: freebsd-arch@freebsd.org
X-Mailer: VM 6.75 under 21.1 (patch 12) "Channel Islands" XEmacs Lucid
Subject: uiomove TDF_DEADLKTREAT
X-BeenThere: freebsd-arch@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Discussion related to FreeBSD architecture
	<freebsd-arch.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-arch>,
	<mailto:freebsd-arch-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-arch>
List-Post: <mailto:freebsd-arch@freebsd.org>
List-Help: <mailto:freebsd-arch-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-arch>,
	<mailto:freebsd-arch-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Tue, 01 Apr 2003 02:02:48 -0000


While glancing through some other code, I noticed that each time
uiomove is called, the sched_lock spinlock is aquired/released twice
to set and then clear some state in td_flags (TDF_DEADLOCKTREAT).


Are these locks/unlocks in the critical path required for non-vfs
callers of uiomove()?  (ie, sosend()/soreceive()?)

Drew