From owner-freebsd-current Fri Feb 7 10:56:35 2003 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id D669237B401; Fri, 7 Feb 2003 10:56:33 -0800 (PST) Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3FF4B43F3F; Fri, 7 Feb 2003 10:56:33 -0800 (PST) (envelope-from robert@fledge.watson.org) Received: from fledge.watson.org (fledge.pr.watson.org [192.0.2.3]) by fledge.watson.org (8.12.6/8.12.5) with SMTP id h17IuLP4084324; Fri, 7 Feb 2003 13:56:21 -0500 (EST) (envelope-from robert@fledge.watson.org) Date: Fri, 7 Feb 2003 13:56:21 -0500 (EST) From: Robert Watson X-Sender: robert@fledge.watson.org To: Hiten Pandya Cc: Julian Elischer , John Baldwin , FreeBSD current users Subject: Re: vnode locking question. In-Reply-To: <20030207172327.GA23165@unixdaemons.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Fri, 7 Feb 2003, Hiten Pandya wrote: > On Thu, Feb 06, 2003 at 10:53:08AM -0800, Julian Elischer wrote the words in effect of: > > > > On Thu, 6 Feb 2003, John Baldwin wrote: > > > > > On 05-Feb-2003 Julian Elischer wrote: > > > > > > > > Is there ever a case when a vnode is locked for longer than the duration > > > > of the syscall that locked it? > > > > > > Shouldn't be. That would be a bug I believe. Userland threads should > > > never hold any kernel locks. > > > > That's what I think too but I just thought I'd ask.. > > (NFS worries me a bit) > > If It did, wouldn't that give a panic() with something like: > "panic: mutex held on exit to userland..." > > ... or something like that? Nope; lockmgr doesn't have that feature, although all the SMPng locking primitives do, I believe. In fact, I believe that's the source of Julian's question, since I've had a conversation with him about adding that sort of sanity checking. In adding that sort of sanity checking, you want to be very sure we don't break any existing assumptions. Robert N M Watson FreeBSD Core Team, TrustedBSD Projects robert@fledge.watson.org Network Associates Laboratories To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message