From owner-cvs-src@FreeBSD.ORG Wed Feb 28 18:01:20 2007 Return-Path: X-Original-To: cvs-src@freebsd.org Delivered-To: cvs-src@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id CF71216A400; Wed, 28 Feb 2007 18:01:20 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (66-23-211-162.clients.speedfactory.net [66.23.211.162]) by mx1.freebsd.org (Postfix) with ESMTP id 2F77713C441; Wed, 28 Feb 2007 18:01:19 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from localhost.corp.yahoo.com (john@localhost [127.0.0.1]) (authenticated bits=0) by server.baldwin.cx (8.13.8/8.13.8) with ESMTP id l1SI1Fex061172; Wed, 28 Feb 2007 13:01:15 -0500 (EST) (envelope-from jhb@freebsd.org) From: John Baldwin To: Greg Lehey Date: Wed, 28 Feb 2007 09:54:52 -0500 User-Agent: KMail/1.9.1 References: <200702272309.l1RN9Xum011236@repoman.freebsd.org> In-Reply-To: <200702272309.l1RN9Xum011236@repoman.freebsd.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200702280954.54068.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH authentication, not delayed by milter-greylist-2.0.2 (server.baldwin.cx [127.0.0.1]); Wed, 28 Feb 2007 13:01:15 -0500 (EST) X-Virus-Scanned: ClamAV 0.88.3/2679/Wed Feb 28 06:58:10 2007 on server.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-4.2 required=4.2 tests=ALL_TRUSTED,AWL,BAYES_00, DATE_IN_PAST_03_06 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on server.baldwin.cx Cc: cvs-src@freebsd.org, src-committers@freebsd.org, cvs-all@freebsd.org Subject: Re: cvs commit: src/share/man/man9 sleep.9 X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 28 Feb 2007 18:01:20 -0000 On Tuesday 27 February 2007 18:09, Greg Lehey wrote: > grog 2007-02-27 23:09:32 UTC > > FreeBSD src repository > > Modified files: > share/man/man9 sleep.9 > Log: > Furhter clarifications: > > - the issues with wakeup_one are due to address space clashes between > unrelated groups of threads. Not unrelated threads really, but more that the same address is being used for two unrelated "events" or "conditions" (hence the name "condition variable"). You can have "related" threads use the same address for different events, and you can have unrelated threads from different processes using the same address for the same event (such as for "accept" where wakeup_one can help a lot) and have proper operation. This is really a programmer bug though (worthy of EDOOFUS), and we don't often detail programmer bugs in man pages. I still feel that this text really isn't clear and probably does more harm than good by discouraging use of wakeup_one() when in fact wakeup_one() can be quite helpful. -- John Baldwin