From owner-svn-src-all@FreeBSD.ORG Mon Feb 6 15:21:59 2012 Return-Path: Delivered-To: svn-src-all@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 530D21065670; Mon, 6 Feb 2012 15:21:59 +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 285B68FC1C; Mon, 6 Feb 2012 15:21:59 +0000 (UTC) Received: from bigwig.baldwin.cx (bigwig.baldwin.cx [96.47.65.170]) by cyrus.watson.org (Postfix) with ESMTPSA id D59ED46B2A; Mon, 6 Feb 2012 10:21:58 -0500 (EST) Received: from jhbbsd.localnet (unknown [209.249.190.124]) by bigwig.baldwin.cx (Postfix) with ESMTPSA id 45F7CB960; Mon, 6 Feb 2012 10:21:56 -0500 (EST) From: John Baldwin To: Ivan Voras Date: Mon, 6 Feb 2012 09:30:31 -0500 User-Agent: KMail/1.13.5 (FreeBSD/8.2-CBSD-20110714-p10; KDE/4.5.5; amd64; ; ) References: <201202041649.q14GnUnI043572@svn.freebsd.org> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <201202060930.31511.jhb@freebsd.org> X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (bigwig.baldwin.cx); Mon, 06 Feb 2012 10:21:58 -0500 (EST) Cc: svn-src-head@freebsd.org, Ryan Stone , src-committers@freebsd.org, svn-src-all@freebsd.org Subject: Re: svn commit: r230984 - head/sys/kern X-BeenThere: svn-src-all@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "SVN commit messages for the entire src tree \(except for " user" and " projects" \)" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 06 Feb 2012 15:21:59 -0000 On Monday, February 06, 2012 6:34:06 am Ivan Voras wrote: > On 4 February 2012 17:49, Ryan Stone wrote: > > Author: rstone > > Date: Sat Feb 4 16:49:29 2012 > > New Revision: 230984 > > URL: http://svn.freebsd.org/changeset/base/230984 > > > > Log: > > Whenever a new kernel thread is spawned, explicitly clear any CPU affinity > > set on the new thread. This prevents the thread from inadvertently > > inheriting affinity from a random sibling. > > Shouldn't new threads inherit affinity from the threads which spawned them? User threads still do, but kernel threads are a bit tricky since most of them get created during boot when everything is running on the BSP, so the affinity they would inherit is rather bogus. Even post-boot many of the cases I can think of when you would create kthreads (e.g. expanding a thread pool), you don't really want to inherit affinity. -- John Baldwin