From owner-freebsd-hackers@FreeBSD.ORG  Wed Aug 20 14:21:16 2003
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
Delivered-To: freebsd-hackers@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id C079F16A4BF
	for <hackers@freebsd.org>; Wed, 20 Aug 2003 14:21:16 -0700 (PDT)
Received: from mail.sandvine.com (sandvine.com [199.243.201.138])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 2A7DF43FDF
	for <hackers@freebsd.org>; Wed, 20 Aug 2003 14:21:16 -0700 (PDT)
	(envelope-from ddolson@sandvine.com)
Received: by mail.sandvine.com with Internet Mail Service (5.5.2653.19)
	id <Q9VDHGGG>; Wed, 20 Aug 2003 17:21:15 -0400
Message-ID: <FE045D4D9F7AED4CBFF1B3B813C8533701919217@mail.sandvine.com>
From: Dave Dolson <ddolson@sandvine.com>
To: "'hackers@freebsd.org'" <hackers@freebsd.org>
Date: Wed, 20 Aug 2003 17:21:14 -0400
MIME-Version: 1.0
X-Mailer: Internet Mail Service (5.5.2653.19)
Content-Type: text/plain;
	charset="iso-8859-1"
Subject: spl protection of selrecord / selwakeup ?
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
	<freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
	<mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
	<mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Wed, 20 Aug 2003 21:21:17 -0000

In FreeBSD 4.7, 

When writing a device driver, which spl 
should be used when calling selrecord or 
selwakeup() ?

Some of the functions called by those functions
(e.g., pfind ) have no protection of their own.

Some drivers use spltty() or splimp().

Can someone explain why splhigh() is not required?

Thanks,
David Dolson (ddolson@sandvine.com, www.sandvine.com)