From owner-svn-src-projects@FreeBSD.ORG Tue May 31 15:01:25 2011 Return-Path: Delivered-To: svn-src-projects@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 3D9F1106566B; Tue, 31 May 2011 15:01:25 +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 14FF68FC0C; Tue, 31 May 2011 15:01:25 +0000 (UTC) Received: from bigwig.baldwin.cx (66.111.2.69.static.nyinternet.net [66.111.2.69]) by cyrus.watson.org (Postfix) with ESMTPSA id B825146B42; Tue, 31 May 2011 11:01:24 -0400 (EDT) Received: from jhbbsd.localnet (unknown [209.249.190.124]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 55E588A01F; Tue, 31 May 2011 11:01:24 -0400 (EDT) From: John Baldwin To: Nathan Whitehorn Date: Tue, 31 May 2011 09:18:39 -0400 User-Agent: KMail/1.13.5 (FreeBSD/8.2-CBSD-20110325; KDE/4.5.5; amd64; ; ) References: <201105271427.p4RERSUb039281@svn.freebsd.org> <201105271202.04421.jhb@freebsd.org> <4DE3FCA0.2000400@freebsd.org> In-Reply-To: <4DE3FCA0.2000400@freebsd.org> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201105310918.39239.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.6 (bigwig.baldwin.cx); Tue, 31 May 2011 11:01:24 -0400 (EDT) Cc: svn-src-projects@freebsd.org, src-committers@freebsd.org Subject: Re: svn commit: r222356 - projects/pseries/kern X-BeenThere: svn-src-projects@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the src " projects" tree" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 31 May 2011 15:01:25 -0000 On Monday, May 30, 2011 4:22:56 pm Nathan Whitehorn wrote: > On 05/27/11 11:02, John Baldwin wrote: > > On Friday, May 27, 2011 10:27:28 am Nathan Whitehorn wrote: > >> Author: nwhitehorn > >> Date: Fri May 27 14:27:28 2011 > >> New Revision: 222356 > >> URL: http://svn.freebsd.org/changeset/base/222356 > >> > >> Log: > >> On multi-core, multi-threaded PPC systems, it is important that the threads > >> be brought up in the order they are enumerated in the device tree (in > >> particular, that thread 0 on each core be brought up first). The SLIST > >> through which we loop to start the CPUs has all of its entries added with > >> SLIST_INSERT_HEAD(), which means it is in reverse order of enumeration > >> and so AP startup would always fail in such situation (causing a machine > >> check or RTAS failure). > >> > >> The best fix is probably to change this from a LIST to a TAILQ, but fix > >> this by looping through to add new cpus to the end of the list. > > Just make it a STAILQ. That has a STAILQ_INSERT_TAIL() method and doesn't > > change the ABI of 'struct pcpu'. It just adds an extra pointer to the head. > > I did that, and it works well. A patch against HEAD can be found at > http://people.freebsd.org/~nwhitehorn/pcpu_tailq.diff. Let me know if it > looks OK (or if there are any objections to committing it). Looks good to me, go for it. -- John Baldwin