From owner-freebsd-hackers Tue Mar 26 14:30:59 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by hub.freebsd.org (Postfix) with ESMTP id 8BAD337B41B for ; Tue, 26 Mar 2002 14:30:54 -0800 (PST) Received: from dan.emsphone.com (smmsp@localhost [127.0.0.1]) by dan.emsphone.com (8.12.2/8.12.2) with ESMTP id g2QMUojc062463; Tue, 26 Mar 2002 16:30:52 -0600 (CST) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.12.2/8.12.2/Submit) id g2QMUnBc062462; Tue, 26 Mar 2002 16:30:49 -0600 (CST) Date: Tue, 26 Mar 2002 16:30:49 -0600 From: Dan Nelson To: Andrew Cc: Terry Lambert , Volker Stolz , Ian , hackers@FreeBSD.ORG Subject: Re: idprio Message-ID: <20020326223049.GC5747@dan.emsphone.com> References: <3CA0D3FE.8113515C@mindspring.com> <20020327092520.V24232-100000@starbug.ugh.net.au> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20020327092520.V24232-100000@starbug.ugh.net.au> User-Agent: Mutt/1.3.28i X-OS: FreeBSD 5.0-CURRENT X-message-flag: Outlook Error Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG In the last episode (Mar 27), Andrew said: > > On Tue, 26 Mar 2002, Terry Lambert wrote: > > > > Sure it can, if the idprio process has locked a vnode trying to update Careful; I wrote the above line, not Terry. > But if system calls aren't preempted under what circumstances can a > process hold a vnode lock and then be usurped for processor? System calls aren't preempted, but if while processing a syscall, the kernel decides to tsleep(), say because of disk I/O (a very common thing when dealing with vnodes :), then another process is free to start running. -- Dan Nelson dnelson@allantgroup.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message