From owner-svn-src-stable@FreeBSD.ORG Wed Feb 18 15:10:56 2009 Return-Path: Delivered-To: svn-src-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 029C210656E3; Wed, 18 Feb 2009 15:10:55 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from cyrus.watson.org (cyrus.watson.org [65.122.17.42]) by mx1.freebsd.org (Postfix) with ESMTP id B6D558FC1D; Wed, 18 Feb 2009 15:10:55 +0000 (UTC) (envelope-from jhb@freebsd.org) Received: from server.baldwin.cx (pool-98-109-39-197.nwrknj.fios.verizon.net [98.109.39.197]) by cyrus.watson.org (Postfix) with ESMTPSA id 53B5F46B35; Wed, 18 Feb 2009 10:10:55 -0500 (EST) Received: from localhost (john@localhost [127.0.0.1]) (authenticated bits=0) by server.baldwin.cx (8.14.3/8.14.3) with ESMTP id n1IFAhsN043449; Wed, 18 Feb 2009 10:10:49 -0500 (EST) (envelope-from jhb@freebsd.org) From: John Baldwin To: Bruce Simpson Date: Wed, 18 Feb 2009 09:49:32 -0500 User-Agent: KMail/1.9.7 References: <200902171957.n1HJvqk8026145@svn.freebsd.org> <499BC43B.6030701@incunabulum.net> In-Reply-To: <499BC43B.6030701@incunabulum.net> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200902180949.32691.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, 18 Feb 2009 10:10:49 -0500 (EST) X-Virus-Scanned: ClamAV 0.94.2/9001/Tue Feb 17 23:29:20 2009 on server.baldwin.cx X-Virus-Status: Clean X-Spam-Status: No, score=-4.4 required=4.2 tests=ALL_TRUSTED,AWL,BAYES_00 autolearn=ham version=3.1.3 X-Spam-Checker-Version: SpamAssassin 3.1.3 (2006-06-01) on server.baldwin.cx Cc: svn-src-stable@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org, svn-src-stable-7@freebsd.org Subject: Re: svn commit: r188727 - in stable/7: sys sys/contrib/pf sys/dev/ath/ath_hal sys/dev/cxgb sys/kern sys/modules/sem sys/sys tools/regression/posixsem usr.bin/procstat X-BeenThere: svn-src-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SVN commit messages for all the -stable branches of the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 18 Feb 2009 15:10:59 -0000 On Wednesday 18 February 2009 3:18:03 am Bruce Simpson wrote: > John Baldwin wrote: > > Author: jhb > > Date: Tue Feb 17 19:57:52 2009 > > New Revision: 188727 > > URL: http://svn.freebsd.org/changeset/base/188727 > > > > Log: > > MFC: Rework the lifetime management of the kernel implementation of POSIX > > semaphores. Specifically, semaphores are now represented as new file > > descriptor type that is set to close on exec. This removes the need for > > all of the manual process reference counting (and fork, exec, and exit > > event handlers) as the normal file descriptor operations handle all of > > that for us nicely. It is also suggested as one possible implementation > > in the spec and at least one other OS (OS X) uses this approach. > > FYI: > This change *may* fix Python 2.6's 'multiprocessing' module on FreeBSD > 7-STABLE, which is known to have problems there; it depends on POSIX > semaphores to synchronize its IPC between different fork()'s of the > Python interpreter. > > If anyone else has an interest in ths they may wish to test, if not, I > will try to get around to it eventually. When Kris tested it, it made things significantly better. I'm not sure if it resolved all the issues though. -- John Baldwin